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2.
Clin. transl. oncol. (Print) ; 20(12): 1557-1570, dic. 2018. ilus, graf
Artigo em Inglês | IBECS | ID: ibc-173762

RESUMO

Purpose: This study aimed to investigate theranostic strategies in colorectal and skin cancer based on fragments of cetuximab, an anti-EGFR mAb, labeled with radionuclide with imaging and therapeutic properties, 111In and 177Lu, respectively. Methods: We designed F(ab′)2-fragments of cetuximab radiolabeled with 111In and 177Lu. 111In-F(ab′)2-cetuximab tumor targeting and biodistribution were evaluated by SPECT in BalbC nude mice bearing primary colorectal tumors. The efficacy of 111In-F(ab′)2-cetuximab to assess therapy efficacy was performed on BalbC nude mice bearing colorectal tumors receiving 17-DMAG, an HSP90 inhibitor. Therapeutic efficacy of the radioimmunotherapy based on 177Lu-F(ab′)2-cetuximab was evaluated in SWISS nude mice bearing A431 tumors. Results: Radiolabeling procedure did not change F(ab′)2-cetuximab and cetuximab immunoreactivity nor affinity for HER1 in vitro. 111In-DOTAGA-F(ab′)2-cetuximab exhibited a peak tumor uptake at 24 h post-injection and showed a high tumor specificity determined by a significant decrease in tumor uptake after the addition of an excess of unlabeled-DOTAGA-F(ab′)2-cetuximab. SPECT imaging of 111In-DOTAGA-F(ab′)2-cetuximab allowed an accurate evaluation of tumor growth and successfully predicted the decrease in tumor growth induced by 17-DMAG. Finally, 177Lu-DOTAGA-F(ab′)2-cetuximab radioimmunotherapy showed a significant reduction of tumor growth at 4 and 8 MBq doses. Conclusions: 111In-DOTAGA-F(ab′)2-cetuximab is a reliable and stable tool for specific in vivo tumor targeting and is suitable for therapy efficacy assessment. 177Lu-DOTAGA-F(ab′)2-cetuximab is an interesting theranostic tool allowing therapy and imaging


No disponible


Assuntos
Animais , Ratos , Nanomedicina Teranóstica/métodos , Cetuximab/uso terapêutico , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Cutâneas/diagnóstico por imagem , Radioimunoterapia/métodos , Modelos Animais de Doenças , Neoplasias Colorretais/terapia , Neoplasias Cutâneas/terapia , Marcação por Isótopo/métodos , Genes erbB-1/efeitos da radiação
3.
Clin Transl Oncol ; 20(12): 1557-1570, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29777377

RESUMO

PURPOSE: This study aimed to investigate theranostic strategies in colorectal and skin cancer based on fragments of cetuximab, an anti-EGFR mAb, labeled with radionuclide with imaging and therapeutic properties, 111In and 177Lu, respectively. METHODS: We designed F(ab')2-fragments of cetuximab radiolabeled with 111In and 177Lu. 111In-F(ab')2-cetuximab tumor targeting and biodistribution were evaluated by SPECT in BalbC nude mice bearing primary colorectal tumors. The efficacy of 111In-F(ab')2-cetuximab to assess therapy efficacy was performed on BalbC nude mice bearing colorectal tumors receiving 17-DMAG, an HSP90 inhibitor. Therapeutic efficacy of the radioimmunotherapy based on 177Lu-F(ab')2-cetuximab was evaluated in SWISS nude mice bearing A431 tumors. RESULTS: Radiolabeling procedure did not change F(ab')2-cetuximab and cetuximab immunoreactivity nor affinity for HER1 in vitro. 111In-DOTAGA-F(ab')2-cetuximab exhibited a peak tumor uptake at 24 h post-injection and showed a high tumor specificity determined by a significant decrease in tumor uptake after the addition of an excess of unlabeled-DOTAGA-F(ab')2-cetuximab. SPECT imaging of 111In-DOTAGA-F(ab')2-cetuximab allowed an accurate evaluation of tumor growth and successfully predicted the decrease in tumor growth induced by 17-DMAG. Finally, 177Lu-DOTAGA-F(ab')2-cetuximab radioimmunotherapy showed a significant reduction of tumor growth at 4 and 8 MBq doses. CONCLUSIONS: 111In-DOTAGA-F(ab')2-cetuximab is a reliable and stable tool for specific in vivo tumor targeting and is suitable for therapy efficacy assessment. 177Lu-DOTAGA-F(ab')2-cetuximab is an interesting theranostic tool allowing therapy and imaging.


Assuntos
Cetuximab/farmacologia , Neoplasias Colorretais , Imunoconjugados/farmacologia , Radioimunodetecção/métodos , Neoplasias Cutâneas , Nanomedicina Teranóstica/métodos , Animais , Cetuximab/farmacocinética , Humanos , Imunoconjugados/farmacocinética , Fragmentos Fab das Imunoglobulinas/farmacologia , Radioisótopos de Índio , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Compostos Radiofarmacêuticos/farmacocinética , Compostos Radiofarmacêuticos/farmacologia , Distribuição Tecidual , Tomografia Computadorizada de Emissão de Fóton Único , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Anaesthesia ; 73(2): 216-222, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29098683

RESUMO

We examined the impact of adding sufentanil during anaesthesia induction with propofol on bispectral index values in elderly patients (≥ 65 years). Patients were randomly assigned to receive a target-controlled sufentanil infusion (effect-site concentration of 0.3 ng.ml-1 ) or matching placebo, followed by a target-controlled propofol induction (initial effect-site concentration of 0.5 µg.ml-1 ; step-wise increase of 0.5 µg.ml-1 ) until loss of consciousness defined as an Observer's Assessment of Alertness/Sedation score < 2. Seventy-one patients (sufentanil 35, placebo 36) completed the study. Mean (SD) age was 72.3 (5.8) years; 41% were women. At loss of consciousness, mean (SD) bispectral index value was 75.0 (8.6) with sufentanil and 70.0 (8.0) with placebo; mean difference -5.0 (95% confidence interval -8.9 to -1.1), p = 0.013. Post-hoc analyses suggest that the difference was significant in men only (mean difference -7.3 (-11.8 to -2.6), p = 0.003). Sufentanil co-induction with propofol results in higher bispectral index values at loss of consciousness in elderly patients.


Assuntos
Anestesia Intravenosa/métodos , Anestésicos Intravenosos , Monitores de Consciência , Sufentanil , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Feminino , Humanos , Masculino , Propofol , Caracteres Sexuais , Inconsciência
5.
Mol Hum Reprod ; 23(11): 738-754, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-29040674

RESUMO

STUDY QUESTION: Do freezing and in vitro culture procedures enhance the expression of proteins involved in apoptotic or autophagic pathways in murine pre-pubertal testicular tissue? SUMMARY ANSWER: IVM strongly modified apoptosis- and autophagy-related relative protein levels in mice testicular tissue whereas the impact of cryopreservation procedures was minimal at the end of the culture. WHAT IS KNOWN ALREADY: In vitro spermatogenesis remains a challenging technical issue as it imposes to find a very close balance between survival and death of germ cell natural precursors (i.e. gonocytes and spermatogonia), which will eventually undergo a complete spermatogenesis close to in vivo conditions. The establishment of efficient culture conditions coupled with suitable cryopreservation procedures (e.g. controlled slow freezing [CSF] and solid surface vitrification [SSV]) of pre-pubertal testicular tissue is a crucial step in the fields of fertility preservation and restoration to improve the spermatic yield obtained in vitro. STUDY DESIGN, SIZE, DURATION: Here, we study cryopreservation procedures (i.e. CSF or SSV) and the impact of culture media compositions. A first set of 66 mouse pre-pubertal testes were directly cultured during 30, 36, 38 and 60 days (D) from 2.5 to 6.5-day-old CD-1 mice to evaluate the impact of time-aspect of culture and to endorse the reverse phase protein microarrays (RPPM) technique as an adapted experimental tool for the field of in vitro spermatogenesis. Ninety others fresh, slow-frozen and vitrified pre-pubertal testes were cultured during 30 days for the principal study to evaluate the impact of cryopreservation procedures before and after culture. Thirty-four testes dissected from 2.5, 6.5, 36.5, 40.5, 42.5 and 62.5 days postpartum (dpp) mice, corresponding to the time frames of spermatogenesis orchestrated in vitro, were used as in vivo controls. PARTICIPANTS/MATERIALS, SETTING, METHODS: After in vitro culture, testicular tissue samples originated from 2.5 or 6.5-day-old CD-1 male mice were analyzed using RPPM. This targeted proteomic technique allowed us to assess the expression level of 29 apoptosis- and autophagy-related factors by normalizing blank-corrected signal values. In addition, morphological analyses (e.g. HES, PAS, TRA98 and CREM) and DNA fragmentation in intra-tubular cells (i.e. terminal deoxynucleotidyl transferase dUTP nick end labeling; TUNEL) were assessed for the distinct experimental conditions tested as well as for in vivo control mouse testes. MAIN RESULTS AND THE ROLE OF CHANCE: A validation of the RPPM procedure in the field of in vitro spermatogenesis was completed with assay and array robustness before a principal study concerning the evaluation of the impact of in vitro culture and cryopreservation procedures. The proportion of elongated spermatids and the total cell number per seminiferous tubule tended to be very different between the in vivo and in vitro conditions (P < 0.05), suggesting the presence of a beneficial regulation on the first spermatogenesis wave by intrinsic apoptosis (Caspase_9) and autophagy (Atg5) factors (P < 0.0003 and r2 = 0.74). Concerning the impact of culture media compositions, a basic medium (BM) composed of αMEM plus 10% KnockOut™ serum replacement and gentamicin supplemented with retinol (Rol) and vitamin E (Vit. E) was selected as the best culture medium for fresh 6.5 dpp tissue cultured during 30D with 27.7 ± 8.10% of seminiferous tubules containing elongated spermatids. Concerning the impact of cryopreservation procedures, SSV did not have any impact on the morphological parameters evaluated after culture in comparison to fresh tissue (FT) controls. The proportion of tubules with elongated spermatids on testicular explants cultured with BMRol+Vit. E was not different between SSV (6.6 ± 1.6%) and CSF (5.3 ± 1.9%); however, round spermatids were observed more frequently for SSV (19 ± 6.2%) than CSF (3.3 ± 1.9%, P = 0.0317). Even if the proportion of TUNEL-positive cells for BMRol+Vit. E was higher at D30 after SSV (4.12 ± 0.26%) than CSF (1.86 ± 0.12%, P = 0.0022) and FT (2.69 ± 0.33%, P = 0.0108), the DNA damages observed at the end of the culture (i.e. D30) were similar to respective 6.5 dpp controls. In addition, the relative protein level expression ratio of an apoptotic factor, the phosphorylated FADD on Fas, was reduced by 64-fold in vitrified testes cultured with BMRol+Vit. E. Furthermore, we found in this study that the StemPro®-34 SFM culture medium supplemented with growth factors (e.g. EGF, bFGF, GDNF and LIF) prevented the differentiation of spermatogonial stem cells in favor of a significant proliferation with a better architectural pattern than in vivo 6.5 dpp controls with an increase of seminiferous tubules area for FT (P = 0.0357) and CSF (P = 0.0317). LIMITATIONS REASONS FOR CAUTION: Despite our promising results, the evaluation of apoptotic- and autophagic-related proteins was studied for a limited amount of proteins and on global testicular tissue. WIDER IMPLICATIONS OF THE FINDINGS: The data presented herein will help to improve apoptotic and autophagic understanding during the first spermatogenic wave. Moreover, our findings illustrate for the first time that, using finely-tuned experimental conditions, a testicular in vitro culture combined with proteomic technologies may significantly facilitate the study of cryopreservation procedures and in vitro culture evaluations. This study may also contribute to improve work on testicular tissues from pre-pubertal and adolescent cancer survivors. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by a Ph.D. grant from the Rouen Normandie Université and a financial support from 'la Ligue nationale contre le cancer' (both awarded to L.D.), funding from Institute for Research and Innovation in Biomedicine (IRIB), Agence de la Biomédecine, and co-supported by European Union and Région Normandie. Europe gets involved in Normandie with European Regional Development Fund (ERDF). The authors declare that there is no conflict of interest.


Assuntos
Proteínas Reguladoras de Apoptose/genética , Proteínas Relacionadas à Autofagia/genética , Criopreservação , Espermatogênese/genética , Espermatozoides/metabolismo , Animais , Animais Recém-Nascidos , Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Autofagia/genética , Proteínas Relacionadas à Autofagia/metabolismo , Diferenciação Celular , Meios de Cultura/química , Fragmentação do DNA , Regulação da Expressão Gênica no Desenvolvimento , Células Intersticiais do Testículo/citologia , Células Intersticiais do Testículo/metabolismo , Masculino , Camundongos , Cultura Primária de Células , Análise Serial de Proteínas , Túbulos Seminíferos/citologia , Túbulos Seminíferos/metabolismo , Células de Sertoli/citologia , Células de Sertoli/metabolismo , Maturidade Sexual/genética , Espermátides/citologia , Espermátides/crescimento & desenvolvimento , Espermátides/metabolismo , Espermatogônias/citologia , Espermatogônias/crescimento & desenvolvimento , Espermatogônias/metabolismo , Espermatozoides/citologia , Espermatozoides/crescimento & desenvolvimento , Vitrificação
6.
Mol Hum Reprod ; 23(10): 674-684, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-28962037

RESUMO

STUDY QUESTION: Is nuclear quality of in vitro generated spermatozoa from fresh or frozen/thawed pre-pubertal mouse testes similar to that of their in vivo counterparts? SUMMARY ANSWER: The production of spermatozoa with aneuploidy, DNA fragmentation or chromatin condensation defects was not significantly increased in organotypic cultures compared to in vivo controls. WHAT IS KNOWN ALREADY: Although murine spermatozoa have been produced in vitro from pre-pubertal testes, their nuclear DNA integrity has never been investigated. STUDY DESIGN, SIZE, DURATION: Fresh and frozen/thawed testicular fragments from 6 to 7 days postpartum (dpp) mice were cultured for 30 days. Testicular tissues were frozen by controlled slow freezing (CSF) or solid surface vitrification (SSV). In total, 30 fresh, 30 CSF, 30 SSV testes were used for in vitro maturation and 6 testes from 36 to 37 dpp mice were used as in vivo controls. PARTICIPANTS/MATERIALS, SETTING, METHODS: Murine spermatozoa were extracted from pooled in vitro cultured testicular fragments and from in vivo controls. Sperm aneuploidy was analyzed by fluorescence in situ hybridization (FISH), DNA fragmentation by terminal deoxynucleotidyl transferase mediated dUTP nick end labeling, chromatin condensation by aniline blue staining, telomere length and number by quantitative FISH, DNA oxidation by immunocytochemical detection of 8-hydroxy-2'-deoxyguanosine (8-OHdG). Because of the low spermatogenic yield in cultures, a hundred spermatozoa extracted from pooled tissues were examined and compared to their in vivo counterparts. MAIN RESULTS AND THE ROLE OF CHANCE: Most of spermatozoa generated in vitro and in vivo were haploid, contained unfragmented DNA and normally condensed chromatin. A similar proportion of spermatozoa with aneuploidy, DNA fragmentation or chromatin condensation defects was found in cultures and in vivo. No significant difference in telomere length was found within the nuclei of in vitro and in vivo generated spermatozoa. However, the number of telomere spots was lower in gametes obtained from cultures of fresh, CSF and SSV testes than in their natural counterparts (P < 0.01). Moreover, the proportion of spermatozoa containing 8-OHdG was significantly increased in frozen/thawed tissues in comparison to fresh tissues and in vivo controls (P < 0.05). LARGE SCALE DATA: None. LIMITATIONS REASONS FOR CAUTION: Further studies will be needed to enhance the production of spermatozoa in organotypic cultures while preserving their quality, to investigate epigenetic modifications and embryonic development. WIDER IMPLICATIONS OF THE FINDINGS: This is the first study comparing the nuclear quality of in vitro and in vivo generated murine spermatozoa. The organotypic culture system will have to be adapted for human tissue and extensive analyses of human gamete quality will have to be performed before potential clinical applications can be envisaged. STUDY FUNDING AND COMPETING INTEREST(S): This work was supported by Rouen University Hospital, Ligue contre le Cancer, Agence de la Biomédecine, Association Laurette Fugain, France Lymphome Espoir, and co-supported by European Union and Région Normandie. Europe gets involved in Normandie with European Régional Development Fund (ERDF). The authors declare that they have no conflict of interest.


Assuntos
Núcleo Celular/ultraestrutura , Criopreservação/métodos , Análise do Sêmen/métodos , Espermatozoides/ultraestrutura , Testículo/citologia , 8-Hidroxi-2'-Desoxiguanosina , Animais , Animais Recém-Nascidos , Núcleo Celular/metabolismo , Fragmentação do DNA , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Feminino , Hibridização in Situ Fluorescente , Masculino , Camundongos , Gravidez , Maturidade Sexual , Espermatogênese/genética , Espermatozoides/metabolismo , Telômero/metabolismo , Telômero/ultraestrutura , Homeostase do Telômero , Testículo/metabolismo , Técnicas de Cultura de Tecidos , Vitrificação
9.
Mol Hum Reprod ; 23(5): 304-320, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28333312

RESUMO

STUDY QUESTION: Can the spatio-temporal formation of an intact blood-testis barrier (BTB), which is essential for the progression of spermatogenesis, be reproduced in cultures of fresh or frozen/thawed prepubertal mouse testes? SUMMARY ANSWER: Organotypic cultures allow the establishment and maintenance of major BTB components and the formation of a functional BTB in mouse testicular tissues. WHAT IS KNOWN ALREADY: In vitro maturation of prepubertal testicular tissues is a promising approach to restore fertility in adult survivors of childhood cancer. Although gametes can be successfully obtained from prepubertal mouse testes in organotypic cultures, the spermatogenic yield remains low compared to in vivo controls. STUDY DESIGN, SIZE, DURATION: Mouse testicular tissues were frozen using controlled slow freezing (CSF) or solid surface vitrification (SSV) procedures. A total of 158 testes (fresh n = 58, CSF n = 58 or SSV n = 42) from 6 to 7 days postpartum (dpp) mice were cultured at 34°C in basal medium (α-MEM, 10% KnockOut Serum Replacement, 5 µg/ml gentamicin) at a gas-liquid interphase (under 20% O2), with or without 10-6 M retinol, for 9, 16 and 30 days. In addition, 32 testes from 6-7, 15-16, 22-23 and 36-37 dpp mice were used as in vivo controls. PARTICIPANTS/MATERIALS, SETTING, METHODS: The mRNA levels of BTB genes (Claudin 3, Claudin 11, Zonula occludens 1 and Connexin-43), germ cell-specific genes (Sal-like protein 4, Kit oncogene, Stimulated by retinoic acid gene 8, Synaptonemal complex protein 3, Transition protein 1 and Protamine 2), markers of Sertoli cell immaturity/maturity (anti-Mullerian hormone, androgen receptor, cyclin-dependent kinase inhibitor 1b) and the androgen-regulated gene Reproductive homeobox 5 (Rhox5) were measured by quantitative RT-PCR (RT-qPCR). The localization of BTB proteins in seminiferous tubules was studied by immunohistochemistry and spermatogenic progression was evaluated histologically. The integrity of the BTB was assessed using a biotin tracer. MAIN RESULTS AND THE ROLE OF CHANCE: Modest differences in Claudin 11 (Cldn11), Zonula occludens 1 (Zo-1), Connexin-43 (Cx43) transcript levels and in the localization of the corresponding proteins were found between in vitro cultures of fresh or frozen/thawed testes and in vivo controls (P < 0.05). However, a 32-77-fold decrease in Claudin 3 (Cldn3) mRNA levels and a lack of CLDN3 immunolabelling in 36-44% of seminiferous tubules were observed in 30-day organotypic cultures (P < 0.05). Although Sertoli cell maturation and the completion of a full spermatogenic cycle were achieved after 30 days of culture, meiotic and postmeiotic progression was altered in cultured testicular tissues (P < 0.05). Moreover, an increased BTB permeability and a decreased expression of Rhox5 were observed at the end of the culture period in comparison with in vivo controls (P < 0.05). Completion of spermatogenesis occurred in vitro in seminiferous tubules with an intact BTB, and in those expressing or lacking CLDN3. LARGE SCALE DATA: None. LIMITATIONS, REASONS FOR CAUTION: Further studies will be needed to determine whether the expression of other BTB components is altered and to decipher the reason for lower Cldn3 and Rhox5 mRNA levels in organotypic cultures. WIDER IMPLICATIONS OF THE FINDINGS: This work contributes to a better understanding of the molecular mechanisms occurring in in vitro matured prepubertal testes. The organotypic culture system will have to be developed further and optimized for human tissue, before potential clinical applications can be envisaged. STUDY FUNDING AND COMPETING INTEREST(S): This work was supported by Rouen University Hospital, Ligue contre le Cancer (to L.D.), and co-supported by European Union and Région Normandie (to A.O.). Europe gets involved in Normandie with European Régional Development Fund (ERDF). The authors declare that they have no conflict of interest.


Assuntos
Barreira Hematotesticular/metabolismo , Claudina-3/deficiência , Criopreservação/métodos , Regulação da Expressão Gênica no Desenvolvimento , Células de Sertoli/metabolismo , Espermatogênese/genética , Animais , Hormônio Antimülleriano/genética , Hormônio Antimülleriano/metabolismo , Diferenciação Celular , Claudina-3/genética , Claudinas/genética , Claudinas/metabolismo , Conexina 43/genética , Conexina 43/metabolismo , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Masculino , Camundongos , Permeabilidade , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Células de Sertoli/citologia , Maturidade Sexual/genética , Transdução de Sinais , Técnicas de Cultura de Tecidos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Vitrificação , Proteína da Zônula de Oclusão-1/genética , Proteína da Zônula de Oclusão-1/metabolismo
10.
Mol Hum Reprod ; 22(12): 819-832, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27671755

RESUMO

STUDY QUESTION: Does vitamin A (retinol, Rol) prevent round spermatid nuclear damage and increase the production of motile sperm during in vitro maturation of vitrified pre-pubertal mouse testicular tissue? SUMMARY ANSWER: The supplementation of an in vitro culture of ~0.75 mm3 testicular explants from pre-pubertal mice with Rol enhances spermatogenesis progression during the first spermatogenic wave. WHAT IS KNOWN ALREADY: The production of functional spermatozoa in vitro has only been achieved in the mouse model and remains a rare event. Establishing an efficient culture medium for vitrified pre-pubertal testicular tissue is now a crucial step to improve the spermatic yield obtained in vitro. The role of Rol in promoting the differentiation of spermatogonia and their entry into meiosis is well established; however, it has been postulated that Rol is also required to support their full development into elongated spermatids. STUDY DESIGN, SIZE, DURATION: A total of 60 testes from 6.5 days post-partum (dpp) mice were vitrified/warmed, cut into fragments and cultured for 30 days: 20 testes were used for light microscopy and histological analyses, 20 testes for DNA fragmentation assessment in round spermatids and 20 testes for induced sperm motility assessment. Overall, 16 testes of 6.5 dpp were used as in vitro fresh tissue controls and 12 testes of 36.5 dpp mice as in vivo controls. Testes were vitrified with the optimal solid surface vitrification procedure and cultured with an in vitro organ culture system until Day 30 (D30). Histological analysis, cell death, degenerating round spermatids, DNA fragmentation in round spermatids and induced sperm motility were assessed. Testosterone levels were measured in media throughout the culture by radioimmunoassay. MAIN RESULTS AND THE ROLE OF CHANCE: At D30, better tissue development together with higher differentiation of spermatogonial stem cells, and higher global cell division ability were observed for vitrified/warmed testicular fragments of ~0.75 mm3 with a culture medium supplemented with Rol compared to controls. During in vitro culture of vitrified pre-pubertal testicular tissue, Rol enhanced and maintained the entry of spermatogonia into meiosis and promoted a higher spermatic yield. Furthermore, decreased round spermatid nuclear alterations and DNA damage combined with induced sperm motility comparable to in vivo highlight the crucial role of Rol in the progression of spermatogenesis during the first wave. LIMITATIONS, REASONS FOR CAUTION: Despite our promising results, the culture media will have to be further improved and adapted within the context of a human application. WIDER IMPLICATIONS OF THE FINDINGS: The results have potential implications for the handling of human pre-pubertal testicular tissues cryopreserved for fertility preservation. However, because some alterations in round spermatids persist after in vitro culture with Rol, the procedure needs to be optimized before human application, bearing in mind that the murine and human spermatogenic processes differ in many respects. LARGE SCALE DATA: None. STUDY FUNDING AND COMPETING INTERESTS: This study was supported by a Ph.D. grant from the Normandy University and a financial support from 'la Ligue nationale contre le cancer' (both awarded to L.D.), funding from Rouen University Hospital, Institute for Research and Innovation in Biomedicine (IRIB) and Agence de la Biomédecine. The authors declare that there is no conflict of interest.


Assuntos
Espermátides/efeitos dos fármacos , Espermátides/metabolismo , Testículo/citologia , Vitamina A/farmacologia , Animais , Morte Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Criopreservação , Fragmentação do DNA/efeitos dos fármacos , Técnicas In Vitro , Masculino , Camundongos , Espermatogênese/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Vitrificação
11.
Andrology ; 3(3): 611-25, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26013105

RESUMO

Testicular tissue cryopreservation offers the hope of preserved future fertility to pre-pubertal boys with cancer before exposition to gonadotoxic treatments. The objective of this study was to compare controlled slow freezing (CSF) with five vitrification techniques for cryopreservation of murine pre-pubertal testicular tissue and to evaluate the best protocol that could provide a successful completion of spermatogenesis after in vitro maturation. Testicular tissue from 24 mice at 6.5 days post-partum (dpp) was used to compare several vitrification protocols with one another, as well as with a CSF protocol. Toxicity test using additional 12 mice was performed for all cryopreservation solutions. Fresh tissue (FT) from six mice was used as a control. Once the optimal vitrification protocol was selected [the modified solid surface vitrification No. 1 (mSSV1 )], testes from 18 mice were cultured in vitro for 30 days with (i) fresh, (ii) slow-frozen/thawed and (iii) vitrified/warmed tissues. Testes from six mice at 36.5 dpp were used as controls. At day 30 of in vitro culture, germ cells of the seminiferous tubules showed a high ability to proliferate and elongated spermatids were observed after both freezing techniques, confirming the successful completion of in vitro spermatogenesis. However, after mSSV1 , the morphological alterations and the percentage of pyknotic seminiferous tubules were lower than CSF (4.67 ± 0.53 vs. 10.1 ± 1.12 and 22.7 ± 2.83% vs. 37.3 ± 4.24% respectively). Moreover, the number of flagellated spermatozoa produced per mg of tissue was higher for mSSV1 than for CSF (35 ± 3 vs. 9 ± 4 cells), with amounts of secreted testosterone during the culture close to those of FT. The mSSV1 protocol resulted in success rates better than CSF in maintaining testicular tissue structure, tubular morphology and tissue functions not solely for immediate frozen/thawed tissues but also after a long-term in vitro culture.


Assuntos
Criopreservação/métodos , Espermatogênese/fisiologia , Espermatozoides/citologia , Vitrificação , Animais , Proliferação de Células , Flagelos/fisiologia , Células Intersticiais do Testículo/citologia , Masculino , Camundongos , Preservação do Sêmen , Túbulos Seminíferos/citologia , Células de Sertoli/citologia , Testosterona/metabolismo
13.
Vox Sang ; 107(2): 103-13, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24650183

RESUMO

Platelet components became routinely available to many institutions in the late 1960s and since then utilization has steadily increased. Platelets are produced by three principal methods and their manufacturing process is regulated by multiple agencies. As the field of platelet transfusion has evolved, a broad array of strategies to improve platelet safety has developed. This review will explore the evolution of modern platelet component therapy, highlight the various risks associated with platelet transfusion and describe risk reduction strategies that have been implemented to improve platelet transfusion safety. In closing, the reader will be briefly introduced to select investigational platelet and platelet-mimetic products that have the potential to enhance platelet transfusion safety in the near future.


Assuntos
Incompatibilidade de Grupos Sanguíneos/imunologia , Transfusão de Plaquetas/efeitos adversos , Lesão Pulmonar Aguda/etiologia , Bacteriemia/etiologia , Plaquetas/imunologia , Plaquetas/microbiologia , Humanos , Risco , Choque/etiologia
15.
Gynecol Obstet Fertil ; 41(9): 548-50, 2013 Sep.
Artigo em Francês | MEDLINE | ID: mdl-23972917

RESUMO

The survival of the young boy after cancer has considerably progressed in recent years due to the efficiency of chemo/radiotherapy against the tumor cells. However, this treatment causes adverse effects on healthy tissues, including fertility. Freezing testicular tissue before highly gonadotoxic treatment is a prerequisite for preserving fertility in prepubertal boys that do not produce sperm yet. But which strategy proposes to restore fertility from frozen-thawed testicular tissue? One potential solution would be to consider an in vitro maturation of spermatogonial stem cells. In this article we trace the chronological development of in vitro spermatogenesis that resulted in mouse sperm production in vitro and give an overview of new challenges for the future.


Assuntos
Células-Tronco Adultas/fisiologia , Preservação da Fertilidade/métodos , Espermatogênese , Animais , História do Século XX , História do Século XXI , Masculino , Camundongos , Técnicas de Cultura de Órgãos/história , Técnicas de Cultura de Órgãos/métodos
16.
Ann Chir Plast Esthet ; 58(2): 175-9, 2013 Apr.
Artigo em Francês | MEDLINE | ID: mdl-21885179

RESUMO

Huriez disease is a rare autosomal dominant pathology characterized by the triad hypoplastic nail, hyperkeratosis and scleroatrophy of distal extremities. One of its most principal complications is the development of an aggressive squamous cell carcinoma. We present a case of a 62-year old patient who had an acute two hands scleroatrophy associated with recurrent squamous cell carcinoma treated by large excision and covered by trophic and thick radial forearm flap. This flap allowed us to treat the wound and the sclerosis shrinkage with aim to give back the functional benefit to the patient. It also gave the patient an oncological treatment despite aggressive management in one step surgery. Furthermore, one year later we did not observe cutaneous flap histological modification that could have degenerated into cancer. A multidisciplinary approach with dermatologists, geneticists and plastic surgeons is essential in addition with close medical supervision because of high cancer risks.


Assuntos
Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Ceratose/complicações , Esclerodermia Localizada/complicações , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/cirurgia , Retalhos Cirúrgicos , Carcinoma de Células Escamosas/etiologia , Seguimentos , Antebraço/cirurgia , Mãos , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Raras , Procedimentos de Cirurgia Plástica , Neoplasias Cutâneas/complicações , Neoplasias Cutâneas/etiologia , Resultado do Tratamento
17.
Ann Chir Plast Esthet ; 56(6): 555-7, 2011 Dec.
Artigo em Francês | MEDLINE | ID: mdl-21962868

RESUMO

Animal experimentation is the most common way to learn microsurgery. However, this practice should be performed according to ethical rules and financial cost. This study has a triple aim: improving students' skills in microsurgery, respecting ethics and reducing costs by using fewer animals. We propose an ethical, practical and inexpensive training method that uses sewing needles. This training consists in microsurgery wire's passages in the eye of sewing needles arranged into circle. Specifically, 24 needles were arranged into two circles on a polystyrene block representing a "double clock". A specific scorecard for this exercise was made to evaluate the students. In total, between November 2010 and June 2011, fifteen residents followed the university degree in microsurgery provided by the faculty of medicine Henri Warembourg (Lille, France). The "double clock" was added to the eight already existing microsurgical manipulations. All of the participants were tested and this exercise was found to be effective as a teaching procedure. Also, each student used an average of 20 rats per year. This year we have reduced our animal control by 10% or about 30 rats. Our goals were achieved as we have improved student's microsurgical skills and also limiting cost by using fewer animals.


Assuntos
Cirurgia Geral/educação , Microcirurgia/educação , Animais , Educação Médica/métodos , Modelos Animais
18.
Ann Chir Plast Esthet ; 56(3): 219-31, 2011 Jun.
Artigo em Francês | MEDLINE | ID: mdl-20646817

RESUMO

Prevention of thrombosis in microsurgery was the point of numerous publications without any referenced protocol. The question of this article was to know if it existed, for a patient who needed a microsurgical procedure, any medical treatment used, proved to lower the thrombotic risk. Using principles of evidence-based medicine, we observed that none of the medical treatments proved efficiency on preventing vascular thrombosis, arterial or venous. The low molecular weight heparins (LMWH) could be used on postoperatives to prevent the deep venous thrombosis of lower limbs but not to lower specially the microvascular thrombosis rate. Aspirin did not improve the positive rates and its adjunction to LMWH increased the bleeding. The evidence-based medicine, as we used it here, permits to conclude that the microsurgeon should not wait any miracle of the medical treatments. Until scientific studies prove efficacity of a treatment, the surgeon has to make a personal choice: keeping habits or following evidence-based medicine. The experience of the surgeon, of the anesthetist and of the paramedical team seem to be the main point to decrease the thrombotic risk during the multidisciplinary healing care of the patient.


Assuntos
Medicina Baseada em Evidências , Fibrinolíticos/uso terapêutico , Microcirurgia/métodos , Trombose/prevenção & controle , Anticoagulantes/uso terapêutico , Heparina de Baixo Peso Molecular/uso terapêutico , Humanos , Inibidores da Agregação Plaquetária/uso terapêutico , Vasodilatadores/uso terapêutico , Trombose Venosa/prevenção & controle
19.
Chir Main ; 29(2): 100-8, 2010 Apr.
Artigo em Francês | MEDLINE | ID: mdl-20299262

RESUMO

Thrombosis is still the first cause of microsurgery failure. Lots of publications have been made but no consensus exists. We first analysed the results of our study in 53 French expert surgeons, then we compared them with the last published datas, most of all, with the similar surveys. If a big majority (81 %) of the surgeons use a preventing method, we observed majors variations between them and also compared to the anglosaxons surgeons habits. This survey permits to make the point on today's practice and to show that some of them are based on low proof level and something even done without any medical references. After datas analysis, we observed that none of the medical treatments proved efficiency on preventing vascular thrombosis. The low molecular weight heparins (LMWH) could be used on postops without increase bleeding but not to lower specially the microvascular thrombosis rate. Aspirin did not improve the positive rates and its adjonction to LMWH increased the bleeding. Until scientific studies prove efficacy of a treatment, the surgeon has to make a personal choice: keeping habits or following evidence-based medicine.


Assuntos
Fibrinolíticos/uso terapêutico , Microcirurgia/efeitos adversos , Padrões de Prática Médica/organização & administração , Trombose/prevenção & controle , Extremidade Superior/cirurgia , Aspirina/uso terapêutico , Clopidogrel , Monitoramento de Medicamentos/métodos , Prática Clínica Baseada em Evidências , Fibrinolíticos/efeitos adversos , França/epidemiologia , Hemorragia/induzido quimicamente , Hemorragia/epidemiologia , Hemorragia/prevenção & controle , Heparina/uso terapêutico , Humanos , Microcirurgia/métodos , Microcirurgia/estatística & dados numéricos , Assistência Perioperatória/métodos , Inibidores da Agregação Plaquetária/uso terapêutico , Pirrolidinas/uso terapêutico , Projetos de Pesquisa , Fatores de Risco , Transplante de Pele/efeitos adversos , Transplante de Pele/métodos , Retalhos Cirúrgicos , Trombose/epidemiologia , Trombose/etiologia , Ticlopidina/análogos & derivados , Ticlopidina/uso terapêutico
20.
Vox Sang ; 99(1): 34-43, 2010 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-20202178

RESUMO

BACKGROUND: The haemolysis level at the end of storage is a performance parameter for RBC preparations. In the evaluation of new devices or new processes for processing blood, it is relevant to evaluate whether the haemolysis is linked to (1) specific characteristics of the blood donor, or (2) the nature of the blood-processing methodologies. MATERIALS AND METHODS: As part of the validation of a new automated whole blood processing system compared to the current manual methods, randomized, paired crossover studies were conducted evaluating measures of blood component quality, including RBC haemolysis over 42 days of storage. RESULTS: The association between haemolysis and the individual subject was evaluated by modelling haemolysis with independent predictors of treatment (control and test processing) and leucocyte reduction as fixed factors with donor and laboratory as random effects in a mixed-effects ANOVA model. It was found that the day 42 haemolysis values were strongly dependent on the donor subject, with an intraclass correlation coefficient of 0.81. CONCLUSIONS: The data reported in this study suggest a link between the specific whole blood donor and the haemolysis levels observed in red-blood-cell units stored refrigerated for 42 days. Additional research to identify possible donor characteristics associated with haemolysis during storage is warranted.


Assuntos
Preservação de Sangue/métodos , Transfusão de Eritrócitos/métodos , Eritrócitos/citologia , Preservação de Sangue/instrumentação , Estudos Cross-Over , Transfusão de Eritrócitos/instrumentação , Eritrócitos/fisiologia , Hemólise/fisiologia , Humanos , Estudos Retrospectivos
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