RESUMO
The anatomical, physiological, and developmental changes which arise as children mature through childhood and adolescence support the need to develop new health technologies that meet the specific requirements of children and young people (CYP). Failing to involve CYP during the development of technology increases the risk that the outcome falls short of their expectations and needs, leading to rejection of novel interventions. Through participation in health technology development, CYP and their families can provide context, insight, personal experience and tacit knowledge to ensure that the end-product is usable, acceptable, and can be integrated into its intended environment. A nuanced, balanced understanding of the methods that can be used to facilitate participation will support researchers in choosing an effective approach to involving CYP in health technology development. Methodological approaches include patient and public involvement and engagement, co-design, and experienced based co-design. These methods can be used in isolation or in combination, to facilitate meaningful involvement of CYP and encourage the development of impactful solutions, in consideration of the context, stakeholders, and objectives of the project. We provide the rationale and justification for involving CYP in health technology design and development, an explanation of the methods supporting meaningful involvement, and case studies exemplifying real world application of these methods with positive outputs.
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Tecnologia Biomédica , Desenvolvimento Industrial , Adolescente , Criança , HumanosRESUMO
NIHR (National Institute for Health Research) Devices for Dignity MedTech Cooperative (D4D) and NIHR Children and Young People MedTech Cooperative (CYPMedTech) have established track records in keeping patient and public involvement (PPI) at the core of medical technology development, evaluation and implementation. The 2020 global COVID-19 pandemic presented significant challenges to maintaining this crucial focus. In this paper we describe prior successful methodologies and share examples of the adaptations made in order to continue to engage with patients and the public throughout the pandemic and beyond. We reflect on learning gained from these experiences, and new areas of scope and focus relating to broadening the reach of engagement and representation, along with associated resource requirements and impact metrics.
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COVID-19 , Adolescente , Criança , Humanos , Desenvolvimento Industrial , Pandemias , Participação do Paciente/métodosRESUMO
Millions of children and young people (CYP) in the UK are affected by chronic or rare health conditions. Rapid advances in science and technology have resulted in CYP with chronic and rare conditions now surviving well into adulthood. New technologies have the potential to improve short- and long-term health outcomes for CYP with health conditions, prevent adult onset disease and complications, and reduce the burden on health services. There is thus a need for targeted investment and appropriate governance in child health technology development to address the specific needs of this population; health technology must be versatile to meet the social, anatomical, cognitive, psychological, and physiological changes inherent to childhood development. Despite the growing demand for health technology for a sizeable global population, industry still wrongly perceives the market size is relatively small, and health technology development is often localised and fragmented with limited scope for spread and adoption. These challenges can be overcome by validating and prioritising unmet needs, involving CYP and their families throughout the innovation pathway, facilitating effective partnerships with key stakeholders, and utilising national and international infrastructure and networks. This paper outlines five innovations supported by NIHR Children and Young People MedTech Co-operative that illustrate how common challenges in child health technology development can be overcome. It is essential that we continue to address such challenges and invest in the health and wellbeing of CYP.
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Saúde da Criança , Tecnologia , Adolescente , Adulto , Criança , HumanosRESUMO
The context of child prosthetics is a complex and important area for research and innovation. Yet, like many areas of paediatric medical technology development, there are several barriers to innovating specifically for the unique needs of children (i.e., a relatively small patient population or 'market'). As such, much child prosthetics technology is developed from the downsizing of adult prosthetics, leading to suboptimal outcomes for children and young people. Since 2016, the Starworks Child Prosthetics Research Network has been exploring this space, bringing children and their families together with key opinion leaders from the NHS, clinical Academia and leading National Research Centres with capabilities in child prosthetics with the aim of increasing research across the system. Above all else, Starworks is centred on the needs of children and their families, ensuring they have an equal voice in driving the ongoing research agenda. This article will share key learnings from the creation and development of the Starworks Network that may be applicable and/or adaptable across a wider paediatric medical technology research and innovation landscape. In particular it will discuss how it addressed three key aims of; (1) Addressing child-specific issues; (2) Building a sustainable network; and (3) Fostering impactful innovation.
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Atenção à Saúde , Pesquisa sobre Serviços de Saúde , Adolescente , Adulto , Criança , HumanosRESUMO
BACKGROUND: The use of patient-facing health technologies to manage long-term conditions is increasing; however, children and young people may have particular concerns or needs before deciding to use different health technologies. AIMS: To identify children and young people's reported concerns or needs in relation to using health technologies to self-manage long-term conditions. METHODS: A scoping review was conducted. We searched MEDLINE, PsycINFO and CINAHL in February 2019. Searches were limited to papers published between January 2008 and February 2019. We included any health technology used to manage long-term conditions. A thematic synthesis of the data from the included studies was undertaken. We engaged children with long-term conditions (and parents) to support review design, interpretation of findings and development of recommendations. RESULTS: Thirty-eight journal articles were included, describing concerns or needs expressed by n=970 children and/or young people aged 5-18 years. Most included studies were undertaken in high-income countries with children aged 11 years and older. Studies examined concerns with mobile applications (n=14), internet (n=9), social media (n=3), interactive online treatment programmes (n=3), telehealth (n=1), devices (n=3) or a combination (n=5). Children and young people's main concerns were labelling and identity; accessibility; privacy and reliability; and trustworthiness of information. DISCUSSION: This review highlights important concerns that children and young people may have before using technology to self-manage their long-term condition. In future, research should involve children and young people throughout the development of technology, from identifying their unmet needs through to design and evaluation of interventions.
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Tecnologia Biomédica , Doença Crônica/terapia , Necessidades e Demandas de Serviços de Saúde , Autogestão , Adolescente , Atitude Frente a Saúde , Tecnologia Biomédica/métodos , Criança , Doença Crônica/psicologia , Humanos , Autogestão/métodos , Autogestão/psicologiaRESUMO
Sperm granuloma may develop in the epididymis following vasectomy or chemical insults. Inflammation due to sperm granuloma causes abdominal and scrotal pain. Prolonged and persistent inflammation in the epididymis due to sperm granuloma may lead to infertility. Extravasation of germ cells into the interstitium of epididymis following damage of the epididymal epithelium is one of the primary reasons for sperm granuloma-associated pathology. Since testosterone is vital for the maintenance of epididymal epithelium, we investigated the pathology of sperm granuloma and its relationship with testosterone. Adult rats were treated with a Leydig cell-specific toxicant ethylene dimethane sulfonate (EDS) to eliminate testosterone. At 7 days post-EDS, disrupted epididymal epithelium and sperm granuloma were observed in the caput epididymis. Sperm granuloma and caput were collagen-filled indicating fibrosis. Numerous round apoptotic cells were localized inside the caput lumen and dispersed through the sperm granuloma. Tnp1 (round spermatid marker) was significantly higher in the epididymis of the EDS-treated group compared to controls suggesting the apoptotic cells were round spermatids. Increases in CD68+ macrophages and T cells (CD4 and CD8) support an inflammatory immune infiltration in post-EDS epididymis. However, testosterone replacement following EDS prevented the sperm granuloma-associated pathology. We suggest that the immune response in the sperm granuloma may be due to the increased numbers of apoptotic round spermatids or other testicular tissue components that may be released, in addition to the regression of epididymal epithelium due to testosterone loss. Thus, testosterone replacement prevents EDS-induced sperm granuloma and ameliorates sperm granuloma-associated pathology.
Assuntos
Granuloma/induzido quimicamente , Células Intersticiais do Testículo/efeitos dos fármacos , Mesilatos/farmacologia , Testosterona/metabolismo , Testosterona/farmacologia , Animais , Antígenos CD , Antígenos de Diferenciação Mielomonocítica , Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Proteínas Cromossômicas não Histona/genética , Proteínas Cromossômicas não Histona/metabolismo , Epididimo/efeitos dos fármacos , Epididimo/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Proteínas/genética , Proteínas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Espermatozoides/efeitos dos fármacos , Doenças Testiculares/induzido quimicamente , Testículo/efeitos dos fármacos , TranscriptomaRESUMO
OBJECTIVE: Testosterone depletion induces increased germ cell apoptosis in testes. However, limited studies exist on genes that regulate the germ cell apoptosis. Granzymes (GZM) are serine proteases that induce apoptosis in various tissues. Multiple granzymes, including GZMA, GZMB and GZMN, are present in testes. Th us, we investigated which granzyme may be testosterone responsive and possibly may have a role in germ cell apoptosis aft er testosterone depletion. METHODS: Ethylene dimethane sulfonate (EDS), a toxicant that selectively ablates the Leydig cells, was injected into rats to withdraw the testosterone. The testosterone depletion effects after 7 days post-EDS were verified by replacing the testosterone exogenously into EDS-treated rats. Serum or testicular testosterone was measured by radioimmunoassay. Using qPCR, mRNAs of granzyme variants in testes were quantified. The germ cell apoptosis was identified by TUNEL assay and the localization of GZMK was by immunohistochemistry. RESULTS: EDS treatment eliminated the Leydig cells and depleted serum and testicular testosterone. At 7 days post-EDS, testis weights were reduced 18% with increased germ cell apoptosis plus elevation GZMK expression. GZMK was not associated with TUNEL-positive cells, but was localized to stripped cytoplasm of spermatids. In addition, apoptotic round spermatids were observed in the caput epididymis. CONCLUSIONS: GZMK expression in testes is testosterone dependent. GZMK is located adjacent to germ cells in seminiferous tubules and the presence of apoptotic round spermatids in the epididymis suggest its role in the degradation of microtubules in ectoplasmic specializations. Thus, overexpression of GZMK may indirectly regulate germ cell apoptosis by premature release of round spermatids from seminiferous tubule lumen.
Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Granzimas/metabolismo , Testículo/efeitos dos fármacos , Testosterona/farmacologia , Animais , Apoptose/efeitos dos fármacos , Células Intersticiais do Testículo/efeitos dos fármacos , Células Intersticiais do Testículo/metabolismo , Masculino , Mesilatos , Ratos , Testículo/metabolismo , Testosterona/metabolismoRESUMO
The statins competitively inhibit 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase activity and consequently the synthesis of mevalonate. The use of statins is associated with insulin resistance, presumably due to the impaired differentiation and diminished glucose utilization of adipocytes. We hypothesize that mevalonate is essential to adipocyte differentiation and adipogenic gene expression. Adipo-Red assay and Oil Red O staining showed that an eight-day incubation with 0-2.5 µmol/L lovastatin dose-dependently reduced the intracellular triglyceride content of murine 3T3-F442A adipocytes. Concomitantly, lovastatin downregulated the expression of peroxisome proliferator-activated receptor γ (Pparγ), leptin (Lep), fatty acid binding protein 4 (Fabp4), and adiponectin (AdipoQ) as measured by quantitative real-time polymerase chain reaction (real-time qPCR). The expression of sterol regulatory element binding protein 1 (Srebp-1), a transcriptional regulator of Pparγ and Lep genes, was also suppressed by lovastatin. Western-blot showed that lovastatin reduced the level of CCAAT/enhancer binding protein α (C/EBPα) while inducing a compensatory over-expression of HMG CoA reductase. The impact of lovastatin on intracellular triglyceride content and expression of the adipogenic genes was reversed by supplemental mevalonate. Mevalonate-derived metabolites have essential roles in promoting adipogenic gene expression and adipocyte differentiation.
Assuntos
Adipócitos/metabolismo , Adipogenia/efeitos dos fármacos , Hidroximetilglutaril-CoA Redutases/metabolismo , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Lovastatina/farmacologia , Ácido Mevalônico/metabolismo , Células 3T3 , Adipócitos/efeitos dos fármacos , Adiponectina/biossíntese , Animais , Proteínas Estimuladoras de Ligação a CCAAT/biossíntese , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Sobrevivência Celular , Regulação para Baixo/efeitos dos fármacos , Proteínas de Ligação a Ácido Graxo/biossíntese , Expressão Gênica , Hidroximetilglutaril-CoA Redutases/biossíntese , Hidroximetilglutaril-CoA Redutases/efeitos dos fármacos , Resistência à Insulina , Leptina/biossíntese , Camundongos , PPAR gama/biossíntese , Proteína de Ligação a Elemento Regulador de Esterol 1/biossíntese , Triglicerídeos/metabolismoRESUMO
Recently, huge interest has been generated in investigating the possible therapeutic use of tunable magnetic nanostructures to overcome the existing challenges to treat central nervous system damage related conditions. However, several issues (e.g., biocompatibility or remote controlled actuation for multi-modal therapeutics) limit the use of conventional magnetic nanoparticles for biomedical applications. To address many of these shortcomings, we have synthesized a monodisperse nanoscale system consisting highly water dispersible magnetic nanodots encased in a remotely tunable polyethylene glycol analouge biopolymer shell. The monodisperse nature of the nanospheres, their response to external magnetic field and volumetric transition near physiological temperatures are very attractive, especially for drug delivery systems where triggered release is necessary. To further analyze the potential for combinatorial therapeutics for central nervous system damage related conditions, we have explored the efficiency of the uptake of nanospheres into pheochromocytoma cell line 12 (PC12) cells and assessed several additional measures of neurite outgrowth. We find that nanospheres were readily incorporated into the cytosolic compartment within 3 hours and did not alter the morphology of cellular processes compared to cells not exposed to nanospheres. Quantification of neurite outgrowth did not reveal any significant differences in neurite initiation or elongation between cells treated with moderate level nanomagnet exposure compared to control cultures under similar conditions. Thus, this study reports an attractive nano-scale system with great potential to deliver therapeutics to precise locations within the nervous system for axonal outgrowth and guidance.
Assuntos
Biopolímeros/química , Magnetismo , Nanoestruturas , Neuritos/efeitos dos fármacos , Polietilenoglicóis/química , Animais , Biopolímeros/farmacologia , Células PC12 , RatosRESUMO
Mature rat testes and liver were fixed with Bouin's fluid (BF) or modified Davidson's fixative (mDF) at room temperature (23 °C) or 4 °C, and DNA integrity was examined by the TUNEL assay. When testes were fixed in BF, TUNEL-stained cells were more prevalent than when fixation occurred in mDF. Independent of fixative, TUNEL-staining was higher when testes were fixed at room temperature relative to 4 °C. Significant effects were present for fixative and temperature of fixation, but not their interaction. Relative to BF, mDF also provided for lower TUNEL-staining in liver, but staining was not affected by fixation temperature. Since the TUNEL assay depends on the detection of fragmented DNA strands, harsh fixatives that induce breaks in the DNA can introduce substantial artifacts. Such potential artifacts are especially prevalent in a tissue such as testes with its ongoing division and differentiation activities. Therefore, the current findings lead the authors to conclude that fixation of mature testes in mDF at 4 °C minimizes generation of false TUNEL-positive cells.
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DNA/química , Marcação In Situ das Extremidades Cortadas/métodos , Testículo/química , Fixação de Tecidos/métodos , Ácido Acético/química , Análise de Variância , Animais , Endopeptidase K/química , Fixadores/química , Formaldeído/química , Histocitoquímica , Fígado/química , Masculino , Picratos/química , Ratos , Ratos Sprague-Dawley , TemperaturaRESUMO
There are approximately 1.5 million people who experience traumatic injuries to the brain and 265,000 who experience traumatic injuries to the spinal cord each year in the United States. Currently, there are few effective treatments for central nervous system (CNS) injuries because the CNS is refractory to axonal regeneration and relatively inaccessible to many pharmacological treatments. Smart, remotely tunable, multifunctional micro- and nanocarriers hold promise for delivering treatments to the CNS and targeting specific neurons to enhance axon regeneration and synaptogenesis. Furthermore, assessing the efficacy of treatments could be enhanced by biocompatible nanovectors designed for imaging in vivo. Recent developments in nanoengineering offer promising alternatives for designing biocompatible micro- and nanovectors, including magnetic nanostructures, carbon nanotubes, and quantum dot-based systems for controlled release of therapeutic and diagnostic agents to targeted CNS cells. This review highlights recent achievements in the development of smart nanostructures to overcome the existing challenges for treating CNS injuries.
Assuntos
Axônios/efeitos dos fármacos , Doenças do Sistema Nervoso Central/tratamento farmacológico , Nanoestruturas/uso terapêutico , Regeneração Nervosa/efeitos dos fármacos , Animais , Axônios/fisiologia , Doenças do Sistema Nervoso Central/patologia , Sistemas de Liberação de Medicamentos/métodos , Humanos , Regeneração Nervosa/fisiologiaRESUMO
The diterpene geranylgeraniol (all trans-3,7,11,15-tetramethyl-2,6,10,14-hexadecatetraen-1-ol) suppresses the growth of human liver, lung, ovary, pancreas, colon, stomach and blood tumors with undefined mechanisms. We evaluated the growth-suppressive activity of geranylgeraniol in murine B16 melanoma cells. Geranylgeraniol induced dose-dependent suppression of B16 cell growth (IC(50) = 55 ± 13 µmol/L) following a 48-h incubation in 96-well plates. Cell cycle arrest at the G1 phase, manifested by a geranylgeraniol-induced increase in the G1/S ratio and decreased expression of cyclin D1 and cyclin-dependent kinase 4, apoptosis detected by Guava Nexin™ assay and fluorescence microscopy following acridine orange and ethidium bromide dual staining, and cell differentiation shown by increased alkaline phosphatase activity, contributed to the growth suppression. Murine 3T3-L1 fibroblasts were 10-fold more resistant than B16 cells to geranylgeraniol-mediated growth suppression. Geranylgeraniol at near IC(50) concentration (60 µmol/L) suppressed the mRNA level of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase by 50%. The impact of geranylgeraniol on B16 cell growth, cell cycle arrest and apoptosis were attenuated by supplemental mevalonate, the product of HMG-CoA reductase that is essential for cell growth. Geranylgeraniol and d-δ-tocotrienol, a down-regulator of HMG-CoA reductase, additively suppressed the growth of B16 cells. These results support our hypothesis that mevalonate depletion mediates the tumor-specific growth-suppressive impact of geranylgeraniol. Geranylgeraniol may have potential in cancer chemoprevention and/or therapy.
Assuntos
Diterpenos/farmacologia , Melanoma Experimental/patologia , Ácido Mevalônico/farmacologia , Células 3T3-L1 , Fosfatase Alcalina/metabolismo , Animais , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ciclina D1/metabolismo , Quinase 4 Dependente de Ciclina/metabolismo , Humanos , Lovastatina/farmacologia , Melanoma Experimental/enzimologia , Ácido Mevalônico/análogos & derivados , Camundongos , Vitamina E/análogos & derivados , Vitamina E/farmacologiaRESUMO
BACKGROUND: Nonalcoholic steatohepatitis (NASH) is a hepatic manifestation of the growing metabolic syndrome epidemic that could progress to cirrhosis. Animal models adequately mimicking this condition in humans are scanty. AIM: The objective of our study was to investigate whether high-fat diets (HFD) with adequate methionine and choline levels can induce pathophysiological features typical of human NASH in C57BL/6J mice. METHODS: Forty C57BL/6J mice, divided into control and high-fat (HF) groups, were fed low-fat diet and HFD, ad libitum respectively for 20 weeks. At the end of 20 weeks, animals were sacrificed and assays were performed for blood biomarkers typical of human NASH. Adipose tissue depots were collected and liver samples were processed for histological examination. RESULTS: High-fat feeding led to increased triglyceride accumulation in the liver (8.9 µmol/100 mg liver tissue vs. 2.6 µmol/100 mg for control) and induced histopathological features of human NASH including hepatic steatosis, ballooning inflammation and fibrosis. Expressions of proteins and chemokines predominant in NASH including collagens I, III and IV and platelet derived growth factor (PDGF) A and B were significantly higher in animals fed the HFD. Liver enzymes alanine transaminase, aspartate transaminase and alkaline phosphatase were significantly (P<.05) elevated in the HF group compared to controls. Mice on HFD also developed hyperglycemia, hyperinsulinemia, hypoadiponectinemia along with elevated tumor necrosis factor α, resistin, leptin, free fatty acids, transforming growth factor ß and malondialdehyde levels that characterize NASH in humans. CONCLUSION: Long-term HF feeding with adequate methionine and choline can induce many of the pathophysiological features typical of human NASH in C57BL/6J mice.
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Modelos Animais de Doenças , Fígado Gorduroso/metabolismo , Tecido Adiposo/metabolismo , Animais , Dieta com Restrição de Gorduras , Dieta Hiperlipídica , Fígado Gorduroso/patologia , Hepatócitos/enzimologia , Hepatócitos/metabolismo , Fígado/metabolismo , Fígado/patologia , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não AlcoólicaRESUMO
Biocompatible magnetic nanoparticles hold great therapeutic potential, but conventional particles can be toxic. Here, we report the synthesis and alternating magnetic field dependent actuation of a remotely controllable, multifunctional nano-scale system and its marked biocompatibility with mammalian cells. Monodisperse, magnetic nanospheres based on thermo-sensitive polymer network poly(ethylene glycol) ethyl ether methacrylate-co-poly(ethylene glycol) methyl ether methacrylate were synthesized using free radical polymerization. Synthesized nanospheres have oscillating magnetic field induced thermo-reversible behavior; exhibiting desirable characteristics comparable to the widely used poly-N-isopropylacrylamide-based systems in shrinkage plus a broader volumetric transition range. Remote heating and model drug release were characterized for different field strengths. Nanospheres containing nanoparticles up to an iron concentration of 6 mM were readily taken up by neuron-like PC12 pheochromocytoma cells and had reduced toxicity compared to other surface modified magnetic nanocarriers. Furthermore, nanosphere exposure did not inhibit the extension of cellular processes (neurite outgrowth) even at high iron concentrations (6 mM), indicating minimal negative effects in cellular systems. Excellent intracellular uptake and enhanced biocompatibility coupled with the lack of deleterious effects on neurite outgrowth and prior Food and Drug Administration (FDA) approval of PEG-based carriers suggest increased therapeutic potential of this system for manipulating axon regeneration following nervous system injury.
RESUMO
AIM: To examine the expression and regulation of integral membrane protein 2b (Itm2b) in rat male reproductive tissues during sexual maturation and under different treatments by in situ hybridization. METHODS: Testis, epididymis, and vas deferens were collected on days 1-70 to examine Itm2b expression during sexual maturation. To further examine the regulation of Itm2b, adult rats underwent surgical castration and cryptorchidism. Ethylene dimethane sulfonate and busulfan treatments were carried out to test the regulation of Itm2b after destruction of Leydig cells and germ cells. RESULTS: In testis, Itm2b expression was moderately detected in the adluminal area of seminiferous cords on days 1-10, and detected at a low level in the spermatogonia on days 20 and 30. The Itm2b level was markedly increased in Leydig cells from day 20 to day 70. In epididymis and vas deferens, Itm2b was detected from neonate to adults, and the signal gradually increased in accordance with sexual maturation. Itm2b expression was significantly downregulated in epididymis and vas deferens of castrated rats, and strongly stimulated when castrated rats were treated with testosterone. Cryptorchidism led to a significant decline of Itm2b expression in testis and caput epididymis. Itm2b expression in epididymis and vas deferens was significantly decreased after the Leydig cells were destroyed by ethylene dimethane sulfonate. Busulfan treatment produced no obvious change in Itm2b expression in epididymis or vas deferens. CONCLUSION: Our data suggested that Itm2b expression is upregulated by testosterone and might play a role in rat male reproduction.
Assuntos
Epididimo/metabolismo , Proteínas de Membrana/metabolismo , Testículo/metabolismo , Ducto Deferente/metabolismo , Animais , Sequência de Bases , Bussulfano/farmacologia , Primers do DNA , Epididimo/efeitos dos fármacos , Hibridização In Situ , Masculino , Orquiectomia , Ratos , Ratos Wistar , Maturidade Sexual , Testículo/efeitos dos fármacos , Ducto Deferente/efeitos dos fármacosRESUMO
AIM: To quantitatively study the histological changes of the testis and epididymis as a result of a drastic reduction of testosterone secretion. METHODS: Fourteen adult Sprague-Dawley rats were injected intraperitoneally with ethane dimethane sulfonate (EDS, 75 mg/kg) and the same number of animals were injected with normal saline as a control. At days 7 and 12 (after treatment), respectively, half of the animals from each group were killed. The testes and epididymides were removed and tissue blocks embedded in methacrylate resin. The cell number per testis was estimated using the stereological optical disector and some other parameters were obtained using other morphometric methods. RESULTS: The EDS treatment resulted in an almost complete elimination of Leydig cells but had no effect on the numbers of Sertoli cells per testis. At day 7 after EDS treatment, many elongated spermatids were retained in the seminiferous epithelium and many round spermatids could be seen in the epididymal ducts. At day 12, a looser arrangement of spermatids and spermatocytes became evident, with apparent narrow empty spaces being formed between germ cells in an approximately radial direction towards the tubule lumen; the numbers (per testis) of non-type B spermatogonia and spermatocytes were similar to controls, whereas that of type B spermatogonia increased by 59%, and that of early round, elongating and late elongated spermatids decreased by 37%, 72% and 52%, respectively. CONCLUSION: The primary spermatogenic lesions following EDS administration were (i) spermiation failure and (ii) detachment of spermatids and spermatocytes associated with impairment in spermiogenesis and meiosis.
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Epididimo/patologia , Células Intersticiais do Testículo/patologia , Mesilatos/toxicidade , Testículo/citologia , Animais , Epididimo/efeitos dos fármacos , Injeções Intraperitoneais , Células Intersticiais do Testículo/efeitos dos fármacos , Masculino , Mesilatos/administração & dosagem , Ratos , Ratos Sprague-Dawley , Túbulos Seminíferos/patologia , Testículo/efeitos dos fármacos , Testículo/crescimento & desenvolvimento , Testículo/patologiaRESUMO
Lipocalin-type prostaglandin D synthase (L-PGDS) is highly expressed in the adult testis and epididymis of many mammals. The present study was to investigate L-PGDS expression in mouse testis and epididymis during sexual maturation, and the effects of testosterone replacement on L-PGDS expression in epididymis by in situ hybridization and immunohistochemistry. Both L-PGDS mRNA and protein were highly expressed in the interstitial tissue of adult testis. L-PGDS mRNA was first detected on d 30 after birth and exhibited an abundant signal in adult caput and cauda epididymis. L-PGDS immunostaining was first observed on d 30 after birth. There was a strong level of L-PGDS immunostaining in adult epididymis. Castrated male mice were treated with either vehicle or testosterone propionate following 3 d postcastration. L-PGDS expression steadily declined in a time-dependent fashion in control groups. No L-PGDS mRNA expression or immunostaining was detected in the controls for 12 d. When the castrated mice were treated with testosterone propionate for 5 or 12 d, L-PGDS expression was significantly increased in the whole epididymis. These data suggest that L-PGDS expression in mouse epididymis gradually declined in parallel to the declining concentration of endogenous androgen after castration and increased with the treatment of exogenous testosterone, indicating that L-PGDS expression in mouse epididymis was modulated by androgen levels. However, differential expression in different areas of the epididymis may also be influenced by factors derived from the testis.
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Regulação Enzimológica da Expressão Gênica/fisiologia , Oxirredutases Intramoleculares/genética , Orquiectomia , Maturidade Sexual/fisiologia , Testículo/enzimologia , Propionato de Testosterona/administração & dosagem , Animais , Epididimo/enzimologia , Imuno-Histoquímica , Hibridização In Situ , Oxirredutases Intramoleculares/metabolismo , Lipocalinas , Masculino , Camundongos , RNA Mensageiro/metabolismoRESUMO
Lipocalin-type prostaglandin D synthase (L-PGDS), a bifunctional protein, is expressed in the male reproductive organs of many species. However, the expression and regulation of L-PGDS in rat are still uncertain. The present study investigated the regionalization and regulation of L-PGDS expression in rat testis and epididymis by in situ hybridization and immunohistochemistry under the conditions of sexual maturation, castration, and ethylene dimethane sulfonate (EDS) treatments. In sexually mature rats, L-PGDS mRNA was weakly expressed only in the testicular peritubular cells, whereas L-PGDS immunostaining was highly detected in the Leydig cells by Day 70 postpartum. During sexual maturation, L-PGDS mRNA expression was highly detected in the caput, corpus, and cauda of the epididymis 70 days after birth. Compared with normal L-PGDS expression in adult epididymis, both L-PGDS mRNA expression and protein immunostaining were significantly reduced in the caput, corpus, and cauda epididymis after castration. Testosterone propionate treatment induced a significant increase of L-PGDS expression in the epididymis of castrated rats. Compared with adult rat epididymis, L-PGDS mRNA and protein expression was down-regulated after EDS treatment. Testosterone propionate treatment could induce an increase of L-PGDS mRNA and protein expression in the epididymis of EDS-treated rats. In conclusion, both castration and EDS treatments caused a significant decrease of L-PGDS expression in the epididymis, whereas testosterone propionate treatment could induce an increase of L-PGDS expression in the epididymis of both castrated and EDS-treated rats, indicating that L-PGDS expression in the rat epididymis can be up-regulated by testosterone.