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1.
Ann Ig ; 33(6): 543-554, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33565567

RESUMO

Background: Demographic changes have forced communities and people themselves to reshape ageing concepts and approaches and try to develop actions towards active and healthy ageing. In this context, the European Commission launched different private-public partnerships to develop new solutions and answers on questions related to this topic. The European Innovation Partnership on Active and Healthy Ageing, including topic related action groups as well reference sites committed towards a common action to facilitate active and healthy ageing, has contributed key elements for interventions, scaled up best practices and evaluated impact of their action to drive innovation across many regions in Europe over the past years. Methods: This paper describes action taken by A3 action group in the European Innovation Partnership on Active and Healthy Ageing. This paper gives an overview of how the partnership combined the view on frailty coming from public health as well as the clinical management. Results: Within different European regions, to tackle frailty, EIPonAHA partners have conceptualized functional decline and frailty, making use of good practice models working well on community programs. The A3 Group of EIPonAHA has worked alongside a process of innovation, targeting all ageing citizens with the clear goal of involving communities in the preventive approach. Conclusion: Engagement needs of older people with a focus on functionally rather than disease management as primary objective is considered as an overarching concept, also embracing adherence, compliance, empowerment, health literacy, shared decision-making, and activation. Furthermore, training of staff working with ageing people across all sectors needs to be implemented and evaluated in future studies.


Assuntos
Fragilidade , Envelhecimento Saudável , Idoso , Envelhecimento , Europa (Continente) , Fragilidade/prevenção & controle , Humanos , Saúde Pública
2.
Hum Reprod ; 35(5): 1029-1044, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32390056

RESUMO

STUDY QUESTION: Is it possible to co-culture and functionally link human liver and testis equivalents in the combined medium circuit of a multi-organ chip? SUMMARY ANSWER: Multi-organ-chip co-cultures of human liver and testis equivalents were maintained at a steady-state for at least 1 week and the co-cultures reproduced specific natural and drug-induced liver-testis systemic interactions. WHAT IS KNOWN ALREADY: Current benchtop reprotoxicity models typically do not include hepatic metabolism and interactions of the liver-testis axis. However, these are important to study the biotransformation of substances. STUDY DESIGN, SIZE, DURATION: Testicular organoids derived from primary adult testicular cells and liver spheroids consisting of cultured HepaRG cells and hepatic stellate cells were loaded into separate culture compartments of each multi-organ-chip circuit for co-culture in liver spheroid-specific medium, testicular organoid-specific medium or a combined medium over a week. Additional multi-organ-chips (single) and well plates (static) were loaded only with testicular organoids or liver spheroids for comparison. Subsequently, the selected type of medium was supplemented with cyclophosphamide, an alkylating anti-neoplastic prodrug that has demonstrated germ cell toxicity after its bioactivation in the liver, and added to chip-based co-cultures to replicate a human liver-testis systemic interaction in vitro. Single chip-based testicular organoids were used as a control. Experiments were performed with three biological replicates unless otherwise stated. PARTICIPANTS/MATERIALS, SETTING, METHODS: The metabolic activity was determined as glucose consumption and lactate production. The cell viability was measured as lactate dehydrogenase activity in the medium. Additionally, immunohistochemical and real-time quantitative PCR end-point analyses were performed for apoptosis, proliferation and cell-specific phenotypical and functional markers. The functionality of Sertoli and Leydig cells in testicular spheroids was specifically evaluated by measuring daily inhibin B and testosterone release, respectively. MAIN RESULTS AND THE ROLE OF CHANCE: Co-culture in multi-organ chips with liver spheroid-specific medium better supported the metabolic activity of the cultured tissues compared to other media tested. The liver spheroids did not show significantly different behaviour during co-culture compared to that in single culture on multi-organ-chips. The testicular organoids also developed accordingly and produced higher inhibin B but lower testosterone levels than the static culture in plates with testicular organoid-specific medium. By comparison, testosterone secretion by testicular organoids cultured individually on multi-organ-chips reached a similar level as the static culture at Day 7. This suggests that the liver spheroids have metabolised the steroids in the co-cultures, a naturally occurring phenomenon. The addition of cyclophosphamide led to upregulation of specific cytochromes in liver spheroids and loss of germ cells in testicular organoids in the multi-organ-chip co-cultures but not in single-testis culture. LARGE-SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: The number of biological replicates included in this study was relatively small due to the limited availability of individual donor testes and the labour-intensive nature of multi-organ-chip co-cultures. Moreover, testicular organoids and liver spheroids are miniaturised organ equivalents that capture key features, but are still simplified versions of the native tissues. Also, it should be noted that only the prodrug cyclophosphamide was administered. The final concentration of the active metabolite was not measured. WIDER IMPLICATIONS OF THE FINDINGS: This co-culture model responds to the request of setting up a specific tool that enables the testing of candidate reprotoxic substances with the possibility of human biotransformation. It further allows the inclusion of other human tissue equivalents for chemical risk assessment on the systemic level. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by research grants from the Scientific Research Foundation Flanders (FWO), Universitair Ziekenhuis Brussel (scientific fund Willy Gepts) and the Vrije Universiteit Brussel. Y.B. is a postdoctoral fellow of the FWO. U.M. is founder, shareholder and CEO of TissUse GmbH, Berlin, Germany, a company commercializing the Multi-Organ-Chip platform systems used in the study. The other authors have no conflict of interest to declare.


Assuntos
Células Intersticiais do Testículo , Testículo , Adulto , Técnicas de Cocultura , Alemanha , Humanos , Fígado , Masculino
3.
Avian Pathol ; 49(5): 423-427, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32208870

RESUMO

Necrotic enteritis (NE) is one of the most detrimental infectious diseases in the modern poultry industry, characterized by necrosis in the small intestine. It is commonly accepted that NetB-producing C. perfringens type G strains are responsible for the disease. However, based on both macroscopic and histopathological observations, two distinct types of NE are observed. To date, both a haemorrhagic form of NE and the type G-associated non-haemorrhagic disease entity are commonly referred to as NE and the results from scientific research are interchangeably used, without distinguishing between the disease entities. Therefore, we propose to rename the haemorrhagic disease entity to necro-haemorrhagic enteritis.


Assuntos
Toxinas Bacterianas/metabolismo , Galinhas/microbiologia , Infecções por Clostridium/veterinária , Clostridium perfringens/metabolismo , Enterite/veterinária , Enterotoxinas/metabolismo , Necrose/veterinária , Doenças das Aves Domésticas/patologia , Animais , Infecções por Clostridium/microbiologia , Infecções por Clostridium/patologia , Enterite/microbiologia , Enterite/patologia , Intestino Delgado/microbiologia , Intestino Delgado/patologia , Necrose/microbiologia , Doenças das Aves Domésticas/microbiologia , Terminologia como Assunto
4.
Hum Reprod ; 34(3): 403-413, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30753464

RESUMO

STUDY QUESTION: Can full spermatogenesis be achieved after xenotransplantation of prepubertal primate testis tissue to the mouse, in testis or subcutaneously? SUMMARY ANSWER: Intratesticular xenotransplantation supported the differentiation of immature germ cells from marmoset (Callithrix jacchus) into spermatids and spermatozoa at 4 and 9 months post-transplantation, while in subcutaneous transplants, spermatogenic arrest was observed at 4 months and none of the transplants survived at 9 months. WHAT IS KNOWN ALREADY: Auto-transplantation of cryopreserved immature testis tissue (ITT) could be a potential fertility restoration strategy for patients with complete loss of germ cells due to chemo- and/or radiotherapy at a young age. Before ITT transplantation can be used for clinical application, it is a prerequisite to demonstrate the feasibility of the technique and identify the conditions required for establishing spermatogenesis in primate ITT transplants. Although xenotransplantation of ITT from several species has resulted in complete spermatogenesis, in human and marmoset, ITT has not been successful. STUDY DESIGN, SIZE, DURATION: In this study, we used marmoset as a pre-clinical animal model. ITT was obtained from two 6-month-old co-twin marmosets. A total of 147 testis tissue pieces (~0.8-1.0 mm3 each) were transplanted into the testicular parenchyma (intratesticular; n = 40) or under the dorsal skin (ectopic; n = 107) of 4-week-old immunodeficient Swiss Nu/Nu mice (n = 20). Each mouse received one single marmoset testis tissue piece in each testis and 4-6 pieces subcutaneously. Xenotransplants were retrieved at 4 and 9 months post-transplantation and evaluations were performed with regards to transplant survival, spermatogonial quantity and germ cell differentiation. PARTICIPANTS/MATERIALS, SETTING, METHODS: Transplant survival was histologically evaluated by haematoxylin-periodic acid Schiff (H/PAS) staining. Spermatogonia were identified by MAGE-A4 via immunohistochemistry. Germ cell differentiation was assessed by morphological identification of different germ cell types on H/PAS stained sections. Meiotically active germ cells were identified by BOLL expression. CREM immunohistochemistry was performed to confirm the presence of post-meiotic germ cells and ACROSIN was used to determine the presence of round, elongating and elongated spermatids. MAIN RESULTS AND THE ROLE OF CHANCE: Four months post-transplantation, 50% of the intratesticular transplants and 21% of the ectopic transplants were recovered (P = 0.019). The number of spermatogonia per tubule did not show any variation. In 33% of the recovered intratesticular transplants, complete spermatogenesis was established. Overall, 78% of the intratesticular transplants showed post-meiotic differentiation (round spermatids, elongating/elongated spermatids and spermatozoa). However, during the same period, spermatocytes (early meiotic germ cells) were the most advanced germ cell type present in the ectopic transplants. Nine months post-transplantation, 50% of the intratesticular transplants survived, whilst none of the ectopic transplants was recovered (P < 0.0001). Transplants contained more spermatogonia per tubule (P = 0.018) than at 4 months. Complete spermatogenesis was observed in all recovered transplants (100%), indicating a progressive spermatogenic development in intratesticular transplants between the two time-points. Nine months post-transplantation, transplants contained more seminiferous tubules with post-meiotic germ cells (37 vs. 5%; P < 0.001) and fewer tubules without germ cells (2 vs. 8%; P = 0.014) compared to 4 months post-transplantation. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: Although xenotransplantation of marmoset ITT was successful, it does not fully reflect all aspects of a future clinical setting. Furthermore, due to ethical restrictions, we were not able to prove the functionality of the spermatozoa produced in the marmoset transplants. WIDER IMPLICATIONS OF THE FINDINGS: In this pre-clinical study, we demonstrated that testicular parenchyma provides the required microenvironment for germ cell differentiation and long-term survival of immature marmoset testis tissue, likely due to the favourable temperature regulation, growth factors and hormonal support. These results encourage the design of new experiments on human ITT xenotransplantation and show that intratesticular transplantation is likely to be superior to ectopic transplantation for fertility restoration following gonadotoxic treatment in childhood. STUDY FUNDING/COMPETING INTEREST(S): This project was funded by the ITN Marie Curie Programme 'Growsperm' (EU-FP7-PEOPLE-2013-ITN 603568) and the scientific Fund Willy Gepts from the UZ Brussel (ADSI677). D.V.S. is a post-doctoral fellow of the Fonds Wetenschappelijk Onderzoek (FWO; 12M2815N). No conflict of interest is declared.


Assuntos
Espermatogênese , Testículo/fisiologia , Testículo/transplante , Animais , Callithrix , Diferenciação Celular , Criopreservação , Células Germinativas/citologia , Masculino , Camundongos , Túbulos Seminíferos/fisiologia , Células de Sertoli/fisiologia , Espermátides/fisiologia , Espermatogônias/fisiologia , Espermatozoides/fisiologia , Transplante Heterólogo
5.
Avian Pathol ; 48(5): 416-422, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31043060

RESUMO

Over the past 50 years, intentional genetic selection within the broiler industry has led to major improvements in both body weight gain (BWG) and feed conversion efficiency. Next to its economic advantages, enhancing BWG can increase the risk of metabolic and skeletal disorders. The aim of this study was to examine whether higher BWG is a predisposing factor for broiler necrotic enteritis. In this study, 300 broilers were challenged with Clostridium perfringens using a well-established, previously described challenge model. It was found that birds with higher body weight (BW) and BWG before challenge were predisposed to develop more severe necrotic enteritis lesions. After challenge, the average BWG of the birds developing mild to severe lesions dropped significantly, negatively affecting bird welfare and performance. These results show a significant interplay between BWG and the development of necrotic enteritis lesions. This raises the question whether there is a limit to broiler performance with respect to maintaining intestinal health, and whether decreasing BWG (at certain stages of the growth cycle) can be part of a plan to prevent intestinal pathology. RESEARCH HIGHLIGHTS Higher body weight is a predisposing factor to necrotic enteritis in broilers.


Assuntos
Galinhas/crescimento & desenvolvimento , Infecções por Clostridium/veterinária , Clostridium perfringens/patogenicidade , Suscetibilidade a Doenças/veterinária , Enterite/veterinária , Doenças das Aves Domésticas/epidemiologia , Animais , Galinhas/genética , Galinhas/microbiologia , Infecções por Clostridium/epidemiologia , Infecções por Clostridium/microbiologia , Enterite/epidemiologia , Enterite/microbiologia , Feminino , Masculino , Necrose/veterinária , Doenças das Aves Domésticas/microbiologia , Fatores de Risco , Aumento de Peso/genética
6.
Mol Hum Reprod ; 24(2): 47-54, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29244172

RESUMO

Recently, complete in vitro generation of male gametes starting from pluripotent stem cells was obtained in a mouse model with live offspring as a result. This breakthrough was probably due to the use of a stepwise differentiation protocol taking the tightly regulated in vivo situation into account. As shown previously, factors of the TGFß superfamily, metabolites of vitamin A, growth hormones, sex steroids and, most importantly, somatic cell support are major regulators of the development, survival, proliferation and differentiation of male gametes. However, up till now, all differentiation protocols starting from human pluripotent stem cells only focused on one or two of these substantive factors, not taking any timeframe into account, leading to promising but unsatisfying results with low efficiency. Therefore, progress might be achieved by including a stepwise differentiation protocol, including all proven contributing regulators, and therefore mimicking more closely human in vivo spermatogenesis and its temporo-spatial organization. In this review, the indispensable regulators of in vivo spermatogenesis and the outcomes of related human in vitro studies are discussed with the aim of unravelling the most successful combinations of medium factors to be used in future differentiation protocols.


Assuntos
Diferenciação Celular/fisiologia , Células-Tronco Pluripotentes/citologia , Espermatogênese/fisiologia , Animais , Diferenciação Celular/genética , Humanos , Masculino , Camundongos , Espermatogênese/genética , Vitamina A/metabolismo
7.
Hum Reprod ; 33(6): 1009-1022, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29684126

RESUMO

STUDY QUESTION: When does germ cell loss and fibrosis occur in patients with Klinefelter syndrome (KS)? SUMMARY ANSWER: In KS, germ cell loss is not observed in testicular tissue from fetuses in the second semester of pregnancy but present at a prepubertal age when the testicular architecture is still normal, while fibrosis is highly present at an adolescent age. WHAT IS KNOWN ALREADY: Most KS patients are azoospermic at adult age because of a massive germ cell loss. However, the timing when this germ cell loss starts is not known. It is assumed that germ cell loss increases at puberty. Therefore, testicular sperm extraction (TESE) at an adolescent age has been suggested to increase the chances of sperm retrieval at onset of spermatogenesis. However, recent data indicate that testicular biopsies from peripubertal KS patients contain only a few germ cells. STUDY DESIGN, SIZE, DURATION: In this study, we give an update on fertility preservation in adolescent KS patients and evaluate whether fertility preservation would be beneficial at prepubertal age. The possibility of retrieving testicular spermatozoa by TESE was evaluated in adolescent and adult KS men. The presence of spermatogonia and the degree of fibrosis were also analysed in testicular biopsies from KS patients at different ages. The patients were divided into four age groups: foetal (n = 5), prepubertal (aged 4-7 years; n = 4), peripubertal (aged 12-16 years; n = 20) and adult (aged 18-41 years; n = 27) KS patients. PARTICIPANTS/MATERIALS, SETTING, METHODS: In peripubertal and adult KS patients, retrieval of spermatozoa was attempted by semen analysis after masturbation, vibrostimulation, electroejaculation or by TESE. MAGE-A4 immunohistochemistry was performed to evaluate the presence of germ cells in testicular biopsies from foetal, prepubertal, peripubertal and adult KS patients. Tissue morphology was evaluated by haematoxylin-periodic acid Schiff (H/PAS) staining. MAIN RESULTS AND THE ROLE OF CHANCE: Testicular spermatozoa were collected by TESE in 48.1% of the adult KS patients, while spermatozoa were recovered after TESE in only one peripubertal patient (5.0%). Germ cells were detectable in testicular biopsies from 21% of adult men for whom no spermatozoa could be retrieved by TESE and in 31.5% of peripubertal KS boys. Very small numbers of spermatogonia (0.03-0.06 spermatogonia/tubule) were detected in three out of four (75%) prepubertal patients. At a foetal age, the number of germ cells was similar for KS and control samples. Increased signs of fibrosis were not present at foetal and prepubertal ages, but peripubertal and adult KS patients showed high levels of fibrosis. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: Only four prepubertal biopsies were included in this study, but they all showed a very low germ cell number. A high variability in the number of spermatogonia per mm2 was observed in the limited (n = 5) number of foetal biopsies. However, testicular biopsies from prepubertal and foetal Klinefelter patients are difficult to obtain. WIDER IMPLICATIONS OF THE FINDINGS: Testicular tissue banking at a prepubertal age has been suggested as a potential method for fertility preservation in early diagnosed KS boys. However, our results show that a reduction in germ cell number has already taken place in childhood. Therefore, offering testicular tissue banking in young KS boys to prevent subsequent sterility might be a questionable strategy. However, this should be confirmed in a larger study population. STUDY FUNDING/COMPETING INTEREST(S): This project was funded by the scientific Fund Willy Gepts from the UZ Brussel (D.V.S., J.D.S.), grants from the Vrije Universiteit Brussel (E.G.) and a Methusalem grant (K.S.). D.V.S is a post-doctoral fellow of the Fonds Wetenschappelijk Onderzoek (FWO; 12M2815N). No conflict of interest is declared.


Assuntos
Azoospermia/etiologia , Síndrome de Klinefelter/complicações , Análise do Sêmen , Espermatogênese , Adolescente , Adulto , Fatores Etários , Azoospermia/genética , Estudos de Casos e Controles , Criança , Pré-Escolar , Fibrose , Humanos , Síndrome de Klinefelter/genética , Masculino , Puberdade/fisiologia , Recuperação Espermática , Testículo/patologia , Adulto Jovem
8.
Hum Reprod ; 30(2): 256-67, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25505010

RESUMO

STUDY QUESTION: Is it possible to derive a scaffold from human testis for the purpose of tissue engineering and regenerative medicine? SUMMARY ANSWER: We developed a method to produce a cytocompatible decellularized testicular matrix (DTM) while maintaining the native tissue-specific characteristics and components. WHAT IS KNOWN ALREADY: The potential benefits of tissue-specific scaffolds consisting of naturally-derived extracellular matrix (ECM) have been demonstrated using a wide variety of animal and human tissue sources. However, so far, testis scaffolds have never been considered for constructive remodelling purposes. STUDY DESIGN, SIZE, DURATION: Human cadaveric testicular tissue was exposed for 24 or 48 h to 1% Triton X-100 and/or 1% sodium dodecyl sulphate (SDS). Acellular samples were used for further scaffold characterization purposes. PARTICIPANTS/MATERIALS, SETTING, METHODS: The extent of decellularization was evaluated by histology. Confirmation of cell removal in DTM was done by a DNA quantification technique. Retention of testicular tissue-specific characteristics was evaluated by mass spectrometry, immunohistochemistry, Alcian blue staining and scanning electron microscopy. Soluble toxicity and testicular cell attachment was assessed to check the cytocompatibility of DTM scaffolds. MAIN RESULTS AND THE ROLE OF CHANCE: Histological analysis showed that DTM could be obtained by mechanical agitation in 1% SDS for 24 h. The resulting DTM was found to be clear of cells while retaining the typical three-dimensional structure and the major components of the native tissue scaffold, including collagen type I and IV, fibronectin, laminin and glycosaminoglycans. In addition, using proteomic analysis, we revealed numerous additional ECM proteins in DTM, indicating its complex nature. The mass spectrometry data were deposited to the ProteomeXchange with identifier PXD001524. Importantly, we demonstrated that DTM scaffolds are not cytotoxic, as evidenced by MTT assay not showing an aberrant fibroblast proliferation activity after indirect exposure, and support testicular cell attachment and infiltration. LIMITATIONS, REASONS FOR CAUTION: The functionality of human testicular cells in DTM needs to be investigated. WIDER IMPLICATIONS OF THE FINDINGS: Our results suggest that the insights into the molecular composition of the testicular ECM provide new clues for the unravelling of its important yet poorly understood role in regulating testicular function, and DTM-based bioscaffolds are promising components for the development of human in vitro spermatogenesis as a treatment for various types of male fertility disorders.


Assuntos
Matriz Extracelular/química , Medicina Regenerativa/métodos , Testículo/química , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Bélgica , Cadáver , Adesão Celular , Proliferação de Células , Células Cultivadas , Matriz Extracelular/metabolismo , Matriz Extracelular/ultraestrutura , Proteínas da Matriz Extracelular/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Microscopia Eletrônica de Varredura , Orquiectomia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Proteômica/métodos , Pele/citologia , Testículo/metabolismo , Testículo/patologia , Testículo/ultraestrutura , Células Tumorais Cultivadas
9.
Hum Reprod ; 30(12): 2859-70, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26405262

RESUMO

STUDY QUESTION: Is the protein expression window during testicular development affected in prepubertal patients at risk for stem cell loss? SUMMARY ANSWER: Nuclear ubiquitin carboxyl-terminal esterase L1 (UCHL1) expression in Sertoli cells and interstitial expression of inhibin α (INHA), sex-determining region Y-box 9 (SOX9) and steroidogenic acute regulatory protein (STAR) was affected in patients with Klinefelter syndrome. WHAT IS KNOWN ALREADY: Some patients undergoing testicular tissue banking have already been treated before the testis biopsy is taken. These treatments include chemotherapy or hydroxyurea, which can have an influence on the stem cell number and function. A germinal loss occurs in Klinefelter patients, but its cause is currently unknown. STUDY DESIGN, SIZE, DURATION: Parrafin-embedded testicular tissue from 5 fetuses, 25 prepubertal patients and 5 adults was used to characterize the spatial and temporal distribution of different testicular marker proteins during testicular development. Expression of the markers was evaluated in germ cells, Sertoli cell and interstitial cells. The integrity of this time window was analyzed in patients at risk for germ cell loss: patients treated with hydroxyurea (n = 7), patients treated with chemotherapy (n = 6) and patients affected by Klinefelter syndrome (n = 5). PARTICIPANTS/MATERIALS, SETTING, METHODS: Immunohistochemistry was performed in normal fetal, prepubertal and adult testicular tissue to set up a timeline for the expression of melanoma antigen family A4 (MAGE-A4), ubiquitin carboxyl-terminal esterase L1 (UCHL1), octamer-binding transcription factor 4 (OCT4), stage-specific embryonic antigen-4 (SSEA4), homeobox protein NANOG, INHA, anti-Müllerian hormone, androgen receptor (AR), SOX9 and STAR. The established timeline was used to evaluate whether the expression of these markers was altered in patients at risk for germ cell loss (patients treated for sickle cell disease (hydroxyurea) or cancer (chemotherapy) and patients with Klinefelter syndrome). MAIN RESULTS AND THE ROLE OF CHANCE: A protein expression timeline was created using different markers expressed in different testicular cell types. Less positive tubules and less positive cells per tubule were observed for MAGE-A4 and UCHL1 expression in the KS compared with the non-treated group (P < 0.01). Higher nuclear UCHL1 Sertoli cell expression was observed in the KS group compared with the non-treated group (P < 0.05). Higher interstitial expression of INHA (P < 0.05), SOX9 (P < 0.01) and STAR (P < 0.05) was observed in KS compared with the non-treated group. LIMITATIONS, REASONS FOR CAUTION: Important age variations exist in the prepubertal groups. Therefore, data were represented in three age groups. However, owing to the limited access to prepubertal tissue, no statistical comparison was possible between these groups. For the Klinefelter group, tissue was only available from patients older than 12 years. WIDER IMPLICATIONS OF THE FINDINGS: The expression timeline can add knowledge to the process of spermatogenesis and be used to evaluate altered protein patterns in patients undergoing potentially gonadotoxic treatments, to monitor spermatogenesis established in vitro and to unravel causes of germ cell loss in Klinefelter patients.


Assuntos
Células Germinativas/metabolismo , Células de Sertoli/metabolismo , Testículo/metabolismo , Ubiquitina Tiolesterase/metabolismo , Adulto , Humanos , Inibinas/metabolismo , Síndrome de Klinefelter/metabolismo , Células Intersticiais do Testículo/metabolismo , Masculino , Fosfoproteínas/metabolismo , Fatores de Transcrição SOX9/metabolismo , Espermatogênese , Testículo/crescimento & desenvolvimento , Ubiquitina Tiolesterase/genética
10.
Hum Reprod ; 28(4): 897-907, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23427228

RESUMO

STUDY QUESTION: What issues remain to be solved before fertility preservation and transplantation can be offered to prepubertal boys? SUMMARY ANSWER: The main issues that need further investigation are malignant cell decontamination, improvement of in vivo fertility restoration and in vitro maturation. WHAT IS KNOWN ALREADY: Prepubertal boys who need gonadotoxic treatment might render sterile for the rest of their life. As these boys do not yet produce sperm cells, they cannot benefit from sperm banking. Spermatogonial stem cell (SSC) banking followed by autologous transplantation has been proposed as a fertility preservation strategy. But before this technique can be applied in the clinic, some important issues have to be resolved. STUDY DESIGN, SIZE DURATION: Original articles as well as review articles published in English were included in a search of the literature. PARTICIPANTS/MATERIALS, SETTING, METHODS: Relevant studies were selected by an extensive Medline search. Search terms were fertility preservation, cryopreservation, prepubertal, SSC, testis tissue, transplantation, grafting and in vitro spermatogenesis. The final number of studies selected for this review was 102. MAIN RESULTS AND THE ROLE OF CHANCE: Cryopreservation protocols for testicular tissue have been developed and are already being used in the clinic. Since the efficiency and safety of SSC transplantation have been reported in mice, transplantation methods are now being adapted to the human testes. Very recently, a few publications reported on in vitro spermatogenesis in mice, but this technique is still far from being applied in a clinical setting. LIMITATIONS, REASONS FOR CAUTION: Using tissue from cancer patients holds a potential risk for contamination of the collected testicular tissue. Therefore, it is of immense importance to separate malignant cells from the cell suspension before transplantation. Because biopsies obtained from young boys are small and contain only few SSCs, propagation of these cells in vitro will be necessary. WIDER IMPLICATIONS OF THE FINDINGS: The ultimate use of the banked tissue will depend on the patient's disease. If the patient was suffering from a non-malignant disease, tissue grafting might be offered. In cancer patients, decontaminated cell suspensions will be injected in the testis. For patients with Klinefelter syndrome, the only option would be in vitro spermatogenesis. However, at present, restoring fertility in cancer and Klinefelter patients is not yet possible. STUDY FUNDING/COMPETING INTEREST(S): Research Foundation, Flanders (G.0385.08 to H.T.), the Institute for the Agency for Innovation, Belgium (IWT/SB/111245 to E.G.), the Flemish League against Cancer (to E.G.), Kom op tegen kanker (G.0547.11 to H.T.) and the Fund Willy Gepts (to HT). E.G. is a Postdoctoral Fellow of the FWO, Research Foundation, Flanders. There are no conflicts of interest.


Assuntos
Preservação da Fertilidade/métodos , Espermatogônias/transplante , Transplante de Células-Tronco/métodos , Animais , Antineoplásicos/efeitos adversos , Criopreservação , Citometria de Fluxo , Humanos , Masculino , Camundongos , Neoplasias/tratamento farmacológico , Neoplasias/radioterapia , Puberdade , Radioterapia/efeitos adversos , Ratos , Espermatogônias/citologia , Transplante Autólogo
11.
Hum Reprod ; 28(7): 1816-26, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23569082

RESUMO

STUDY QUESTION: Is there a better alternative to the conventional cryopreservation protocols for human testicular tissue banking? SUMMARY ANSWER: Uncontrolled slow freezing (USF) using 1.5 M dimethylsulphoxide (DMSO) and 0.15 M sucrose as cryoprotectants appears to be a user-friendly and efficient method for the cryopreservation of human testicular tissue. WHAT IS KNOWN ALREADY: Currently, time-consuming controlled slow freezing (CSF) protocols that need expensive equipment are commonly used for human testicular tissue banking. USF and vitrification are cryopreservation techniques that were successfully applied in several animal models but need further exploration with human tissue. STUDY DESIGN, SIZE, DURATION: Fragments (n = 160) of testicular tissue from 14 patients undergoing vasectomy reversal were assigned to a fresh control group or one of the following cryopreservation procedures: CSF using DMSO at a concentration of 0.7 or 1.5 M in the presence (+S) or absence of sucrose (-S), USF using either 0.7 or 1.5 M DMSO combined with sucrose, solid-surface vitrification (SSV) or direct cover vitrification (DCV). MATERIALS, SETTING, METHODS: Light microscopic evaluations were performed to study apoptosis, germ cell proliferation ability, spermatogonial survival, coherence of the seminiferous epithelium and integrity of the interstitial compartment after cryopreservation. Ultrastructural alterations were studied by scoring cryodamage to four relevant testicular cell types. MAIN RESULTS AND THE ROLE OF CHANCE: The USF 1.5 M DMSO + S protocol proved not solely to prevent cell death and to preserve seminiferous epithelial coherence, interstitial compartment integrity, SG and their potential to divide but also protected the testicular cell ultrastructure. A significant reduction in the number of SG per tubule from 21.4 ± 5.6 in control tissue to 4.9 ± 2.1, 8.2 ± 5.4, 11.6 ± 5.1, 8.8 ± 3.9, 12.6 ± 4.4 and 11.7 ± 5.7 was observed after cryopreservation combined with at least one other form of cryoinjury when using CSF 0.7 M DMSO -S, CSF 0.7 M DMSO + S, CSF 1.5 M DMSO + S, USF 0.7 M DMSO + S, SSV and direct cover vitrification (DCV), respectively (P < 0.001). LIMITATIONS, REASONS FOR CAUTION: Supplementary research is required to investigate the effect on tissue functionality and to confirm this study's findings using prepubertal tissue. WIDER IMPLICATIONS OF THE FINDINGS: An optimal cryopreservation protocol enhances the chances for successful fertility restoration. USF, being an easy and cost-effective alternative to CSF, would be preferable for laboratories in developing countries or whenever tissue is to be procured from a diseased child at a site distant from the banking facility.


Assuntos
Criopreservação/métodos , Testículo/citologia , Apoptose , Proliferação de Células , Crioprotetores , Humanos , Masculino , Epitélio Seminífero/citologia , Epitélio Seminífero/ultraestrutura , Testículo/ultraestrutura
12.
Hum Reprod Open ; 2023(3): hoad029, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37547664

RESUMO

STUDY QUESTION: What is the long-term impact of presumed gonadotoxic treatment during childhood on the patient's testicular function at adulthood? SUMMARY ANSWER: Although most patients showed low testicular volumes and some degree of reproductive hormone disruption 12.3 (2.3-21.0) years after gonadotoxic childhood therapy, active spermatogenesis was demonstrated in the semen sample of 8 out of the 12 patients. WHAT IS KNOWN ALREADY: In recent decades, experimental testicular tissue banking programmes have been set up to safeguard the future fertility of young boys requiring chemo- and/or radiotherapy with significant gonadotoxicity. Although the risk of azoospermia following such therapies is estimated to be high, only limited long-term data are available on the reproductive potential at adulthood. STUDY DESIGN SIZE DURATION: This single-centre prospective cohort study was conducted between September 2020 and February 2023 and involved 12 adult patients. PARTICIPANTS/MATERIALS SETTING METHODS: This study was carried out in a tertiary care centre and included 12 young adults (18.1-28.3 years old) who had been offered testicular tissue banking prior to gonadotoxic treatment during childhood. All patients had a consultation and physical examination with a fertility specialist, a scrotal ultrasound to measure the testicular volumes and evaluate the testicular parenchyma, a blood test for assessment of reproductive hormones, and a semen analysis. MAIN RESULTS AND THE ROLE OF CHANCE: Testicular tissue was banked prior to the gonadotoxic treatment for 10 out of the 12 included patients. Testicular volumes were low for 9 patients, and 10 patients showed some degree of reproductive hormone disruption. Remarkably, ongoing spermatogenesis was demonstrated in 8 patients at a median 12.3 (range 2.3-21.0) years post-treatment. LIMITATIONS REASONS FOR CAUTION: This study had a limited sample size, making additional research with a larger study population necessary to verify these preliminary findings. WIDER IMPLICATIONS OF THE FINDINGS: These findings highlight the need for multicentric research with a larger study population to establish universal inclusion criteria for immature testicular tissue banking. STUDY FUNDING/COMPETING INTERESTS: This study was conducted with financial support from the Research Programme of the Research Foundation-Flanders (G010918N), Kom Op Tegen Kanker, and Scientific Fund Willy Gepts (WFWG19-03). The authors declare no competing interests. TRIAL REGISTRATION NUMBER: NCT04202094; https://clinicaltrials.gov/ct2/show/NCT04202094?id=NCT04202094&draw=2&rank=1 This study was registered on 6 December 2019, and the first patient was enrolled on 8 September 2020.

13.
Hum Reprod ; 27(4): 998-1004, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22313866

RESUMO

BACKGROUND: Although germ cells in boys with Klinefelter syndrome (KS) are reduced in number as early as infancy, a severe germ cell loss occurs during mid-puberty. Therefore, we wanted to detect spermatogenesis at an early stage and investigate the strategy of preserving spermatozoa and/or testicular spermatogonial stem cells in adolescents with KS when signs of deteriorating spermatogenesis are observed. METHODS: Tanner staging, testicular size, serum inhibin B and spermaturia were assessed every 4 months before the attempt to procure gametogenic cells in seven non-mosaic 47,XXY adolescents, aged between 10 and 16 years. RESULTS: Despite an increasing testis volume in the youngest and a Tanner staging of more than three in the oldest patients, no spermaturia was observed. In two patients serum inhibin B increased gradually, while in all others a rather rapid but variable decline was observed at different ages. No spermatozoa were observed after electroejaculation. No spermatocytes or spermatids were found at microscopic examination of single biopsies, while spermatogonia were identified in four subjects, three of whom had measurable serum inhibin B. Massive fibrosis and hyalinization were observed in all biopsies. CONCLUSION: No spermatogenesis was documented in non-mosaic 47,XXY adolescents either by spermaturia, electroejaculation or testicular biopsy. Neither clinical nor hormonal parameters were of value in determining the timing for optimal spermatogonial stem cell retrieval. More data are needed to elucidate the potential role of testicular tissue cryopreservation in adolescents with KS. Therefore, at present, the cryopreservation of testes tissue for clinical reasons should not be recommended.


Assuntos
Síndrome de Klinefelter/patologia , Espermatogênese , Espermatogônias/patologia , Células-Tronco/patologia , Testículo/patologia , Adolescente , Biópsia , Criança , Criopreservação , Humanos , Inibinas/sangue , Síndrome de Klinefelter/sangue , Masculino , Puberdade , Espermátides/patologia , Espermatócitos/patologia
14.
Hum Reprod ; 27(2): 323-30, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22166807

RESUMO

BACKGROUND: Although early development of testes appears normal in boys with Klinefelter syndrome (KS), spermatogonial stem cell (SSC) depletion occurs in mid puberty, leading to infertility. Cryopreservation of SSCs prior to stem cell loss is an option that is currently offered to boys who have to undergo gonadotoxic treatments. This study aimed to explore the possibility of preserving SSCs in pubertal KS adolescents by testicular tissue banking. METHODS: A retrospective study was conducted in seven non-mosaic 47,XXY adolescents, aged 13-16 years, who were invited for an experimental testicular tissue banking programme during their follow-up at the Paediatric Endocrinology Department of the UZ Brussel between 2009 and 2011. Paraffin-embedded testicular tissue was sectioned and stained with haematoxylin-eosin, and immunostainings were performed for Mage-A4, anti-Mullerian hormone, Inhibin α and steroidogenic acute regulatory protein. The presence of spermatogenesis and/or spermatogonia was evaluated. RESULTS: Massive fibrosis and hyalinization was observed in all but one KS patients. Although spermatogonia were seen in five patients, spermatogonia were only present in tubules showing normal architecture in the youngest patient who also had normal follicle-stimulating hormone and inhibin B concentrations. CONCLUSIONS: Testicular tissue cryopreservation in KS adolescents should be recommended as soon as possible, probably before hormonal changes of failing Sertoli cell function are detected.


Assuntos
Criopreservação , Preservação da Fertilidade , Infertilidade Masculina/prevenção & controle , Síndrome de Klinefelter/fisiopatologia , Preservação do Sêmen , Espermatogônias/patologia , Células-Tronco/patologia , Adolescente , Bélgica , Fibrose , Hormônio Foliculoestimulante/sangue , Seguimentos , Humanos , Hialina/metabolismo , Hiperplasia , Infertilidade Masculina/etiologia , Subunidades beta de Inibinas/sangue , Síndrome de Klinefelter/sangue , Síndrome de Klinefelter/metabolismo , Síndrome de Klinefelter/patologia , Masculino , Puberdade , Estudos Retrospectivos , Espermatogônias/metabolismo , Células-Tronco/metabolismo , Testículo/metabolismo , Testículo/patologia
15.
Acta Clin Belg ; 77(1): 65-70, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32700632

RESUMO

OBJECTIVES: Presenting the Belgian new framework for Advanced Practice Nursing (APN) - 'Verpleegkundig Specialist [VS]'/"Infirmier de pratique avancée [IPA]" outlined in the Law of 22 April 2019, followed by a discussion of the lack of clarity, the current challenges and future opportunities. METHODS: The framework was analyzed by an expert in healthcare legislation and discussed by academics in Nursing Science and members of the board of directors of the Belgian Society of APN. RESULTS: Relevant paragraphs within this new law are"Article 46 §1. No one is allowed to carry the title of 'VS/IPA' who does not possess a bachelor in nursing mentioned in article 45 and who does not meet the requirements specified in this article. At the minimum, a master's degree in Nursing Sciences is also required. §2. Additional to the scope of practice of nursing as mentioned in article 46, the 'VS/IPA' perform, in the context of complex nursing care, medical interventions in order to maintain, improve or restore the health of the patient. Care is provided in the context of a specific target group of patients and in close concertation with the physician and potential other healthcare professionals. CONCLUSION: Although the legal recognition of the title of VS/IPA is a major breakthrough that will innovate healthcare, clarification is needed: How do VS/IPA distinguish themselves from other nursing functions, what is complex nursing care, which medical interventions can be performed, what is meant by specific target group of patients, what does 'in close concertation with the physician' entail, and will advisory power be possible?


Assuntos
Prática Avançada de Enfermagem , Bélgica , Humanos
16.
Int J Infect Dis ; 115: 224-228, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34929362

RESUMO

BACKGROUND: Septicaemia with intravascular haemolysis is a rare, but often fatal, presentation of Clostridium perfringens infection. C. perfringens is a Gram-positive, anaerobic bacterium that can produce multiple toxins. Toxinotyping is not performed regularly. METHODS: This article describes two human cases of C. perfringens infections. Toxinotyping was performed using polymerase chain reaction (PCR). Additionally, a structured review of the literature was performed which searched specifically for cases of C. perfringens infection with haemolysis. RESULTS: Both cases were identified as toxinotype A strains and both cases were fatal. Also, both cases showed marked haemolysis during their clinical course, which is assumed to have played a significant role in their outcome. In total, 83 references were identified describing human C. perfringens infection with haemolysis. Mortality rates have been stable over the last 10 years at 80%. Toxinotyping has been performed in a total of six cases. Of the four cases analysed by PCR, all were identified as toxinotype A. CONCLUSIONS: Haemolytic C. perfringens infections are rare but are fatal in most cases. Toxinotyping is performed rarely. The authors advocate increased use of toxinotyping to gain insight into pathophysiology and more effective interventions.


Assuntos
Infecções por Clostridium , Sepse , Composição de Bases , Infecções por Clostridium/diagnóstico , Clostridium perfringens/genética , Hemólise , Humanos , Filogenia , RNA Ribossômico 16S , Análise de Sequência de DNA
17.
Hum Reprod ; 26(2): 282-93, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21123192

RESUMO

BACKGROUND: Grafting of frozen-thawed testicular tissue has been suggested as a novel fertility preservation method for patients undergoing gonadotoxic treatments. However, this technique still needs further optimization before any clinical application. So far, grafting of human testicular tissue has only been performed to the back skin of nude mice and has shown spermatogonial stem-cell survival and occasionally differentiation up to primary spermatocytes. In this study, orthotopic grafting to mouse testes was evaluated as an alternative, and the effect of freezing and the donor's age was studied. METHODS: Human testicular tissue was obtained from two prepubertal (aged 3 and 5) and two postpubertal (aged 12 and 13) boys. Both fresh and frozen-thawed testicular tissue was grafted to the testis of immuno-deficient nude mice. Four and nine months after transplantation, testes were analyzed by histology and immunohistochemistry. RESULTS: Four and nine months after transplantation, spermatogonial stem cells were observed in all tissue grafts. Germ cell survival was found to be higher in xenografts from the older boys when compared with that from younger donors. Furthermore, no differentiation was observed in the xenografts from younger patients, but the grafts of two older donors showed differentiation up to the primary spermatocyte level, with the presence of secondary spermatocytes in the oldest donor 9 months after transplantation. CONCLUSIONS: This xenografting study shows that intratesticular grafting results in high germ cell survival. In grafts derived from the older boys, meiotic activity was maintained in the xenografts for at least 9 months. Although difficult to conduct due to the scarcity of the tissue, more comparative research is needed to elucidate an optimal grafting strategy.


Assuntos
Espermatogênese , Testículo/transplante , Adolescente , Animais , Diferenciação Celular , Sobrevivência Celular , Criança , Pré-Escolar , Humanos , Masculino , Meiose , Camundongos , Camundongos Nus , Puberdade , Espermatogônias/transplante , Testículo/cirurgia , Transplante Heterólogo
18.
Hum Reprod ; 26(12): 3388-400, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21984576

RESUMO

BACKGROUND: Since spermatogonial stem cell transplantation (SSCT) and testicular tissue grafting (TTG) may have important clinical applications, the safety of these promising techniques has to be proved. This study was designed to characterize epigenetic modifications in prepubertal and adult mouse germ cells and to study these epigenetic mechanisms after SSCT and TTG. METHODS: Testicular cell suspensions were transplanted to the testes of genetically sterile W/W(v) recipients. Intratesticular tissue grafting was performed between green fluorescent protein (GFP(+)) donors and GFP(-) acceptor mice. DNMT1 and DNMT3A expression, the general methylation status and the histone modifications H3K4me3, H3K9ac, H4K5ac, H4K8ac, H4K12ac and H4K16ac were studied in a stage-dependent manner by immunohistochemistry and compared with data from adult control mice. RESULTS: The expression levels of DNMT1 and DNMT3A, the DNA methylation status and most of the stage-specific histone modifications after SSCT or TTG were not different from fertile adult controls. Although, in elongated spermatids, the acetylation pattern was as expected, the stage-dependent expression of H4K5ac and H4K8ac was altered after SSCT. CONCLUSIONS: Intratesticular tissue grafting might be the better choice for fertility restoration. Disrupting the stem cell niche might influence epigenetic patterns. Since the function of H4K5ac and H4K8ac in spermatogonia and spermatocytes still has to be explored, in-depth epigenetical analyses are warranted.


Assuntos
Epigênese Genética , Espermatogônias/transplante , Testículo/transplante , Transplantes , Acetilação , Animais , Metilação de DNA , Histonas/metabolismo , Imuno-Histoquímica , Masculino , Metilação , Camundongos
19.
Int J Clin Pract ; 65(10): 1092-9, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21923848

RESUMO

BACKGROUND: Sexual problems are common amongst cardiac patients, and concerns may arise when resuming sexual activities after a cardiac event. Sexual counselling is therefore indispensible. Culture is an identified barrier to talking about sex, but research is lacking on whether and how culture influences nurses in providing sexual counselling. DESIGN: This cross-sectional descriptive study assessed four areas related to sexual counselling provided by cardiovascular nurses. We investigated the impact of culture on these areas by surveying cardiovascular nurses living in Denmark, Norway and two regions of Belgium - Flanders, Dutch-speaking region and Wallonia, French-speaking region. METHODS: Overall, 819 participants were recruited as they attended cardiovascular nursing congresses in Denmark, Norway and Belgium. Subjects completed the Undertaking Nursing Interventions Throughout Europe (UNITE) sexual counselling questionnaire, measuring practice, responsibility, confidence and perceived comfort of patients. Controlling for demographic, educational and professional covariates, we performed multiple linear regression analysis to determine the impact of culture on sexual counselling. RESULTS: All four subscale scores were independently associated with culture. Danish nurses counselled patients significantly more often, reported feeling more responsibility and confidence and estimated more comfort in patients than Norwegian, Flemish and Walloon nurses. CONCLUSIONS: This study showed that culture matters with respect to sexual counselling for cardiac patients. Interventions should be developed improving sexual counselling of cardiac patients. Educational courses and training of healthcare professionals on sexual counselling should be more sensitive to sociocultural differences. Cross-cultural perspectives may bias attitudes of professionals as they deal with concerns of cardiac patients about resuming sexual activity.


Assuntos
Cultura , Cardiopatias/enfermagem , Aconselhamento Sexual/métodos , Comportamento Sexual/etnologia , Disfunções Sexuais Fisiológicas/enfermagem , Adulto , Competência Clínica/normas , Estudos Transversais , Escolaridade , Europa (Continente)/etnologia , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Cardiopatias/etnologia , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados de Enfermagem/normas , Satisfação do Paciente , Disfunções Sexuais Fisiológicas/etnologia , Inquéritos e Questionários
20.
Reprod Sci ; 28(2): 603-613, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33150486

RESUMO

Cryopreservation of immature testicular tissue is an experimental strategy for the preservation of fertility in prepubertal boys that will be subjected to a gonadotoxic onset, as is the case of oncologic patients. Therefore, the objective of this study was to assess the impact of chemotherapeutic treatments on the testicular histologic phenotype in prepubertal patients. A total of 56 testicular tissue samples from pediatric patients between 0 and 16 years old (28 with at least one previous chemotherapeutic onset and 28 untreated controls) were histologically analyzed and age-matched compared. At least two 5-µm sections from testis per patient separated by a distance of 100 µm were immunostained for the germ cell marker VASA, the spermatogonial markers UTF1, PLZF, UCHL1, and SALL4, the marker for proliferative cells KI67, and the Sertoli cell marker SOX9. The percentage of tubule cross-sections positive for each marker and the number of positive cells per tubule cross-section were determined and association with the cumulative dose received of each chemotherapeutic drug was statistically assessed. Results indicated that alkylating agents, cyclophosphamide and ifosfamide, but also the antimetabolite cytarabine and asparaginase were associated with a decreased percentage of positive tubules and a lower number of positive cells per tubule for the analyzed markers. Our results provide new evidences of the potential of chemotherapeutic agents previously considered to have low gonadotoxic effects such as cytarabine and asparaginase to trigger a severe testicular phenotype, hampering the potential success of future fertility restoration in experimental programs of fertility preservation in prepubertal boys.


Assuntos
Antineoplásicos/efeitos adversos , Asparaginase/efeitos adversos , Ciclofosfamida/efeitos adversos , Citarabina/efeitos adversos , Fertilidade/efeitos dos fármacos , Ifosfamida/efeitos adversos , Infertilidade Masculina/induzido quimicamente , Espermatozoides/efeitos dos fármacos , Testículo/efeitos dos fármacos , Adolescente , Fatores Etários , Bélgica , Estudos de Casos e Controles , Criança , Pré-Escolar , RNA Helicases DEAD-box/metabolismo , Preservação da Fertilidade , Humanos , Infertilidade Masculina/metabolismo , Infertilidade Masculina/patologia , Infertilidade Masculina/fisiopatologia , Antígeno Ki-67/metabolismo , Masculino , Proteínas Nucleares/metabolismo , Projetos Piloto , Proteína com Dedos de Zinco da Leucemia Promielocítica/metabolismo , Medição de Risco , Fatores de Transcrição SOX9/metabolismo , Espanha , Espermatozoides/metabolismo , Espermatozoides/patologia , Testículo/metabolismo , Testículo/patologia , Testículo/fisiopatologia , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Ubiquitina Tiolesterase/metabolismo
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