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A teaching module is a learning tool or design based on a curriculum applied to achieve predetermined competency standards. This research aims to use the ADDIE development model to produce a science teaching module based on search, solve, crate and share (SSCS) on valid, practical and effective living things classification concepts. This research was conducted at SMP Negeri 1 Molibagu involving 24 students in Class VII C. The study showed that the results of validating the Science Teaching Module (STM) based on SSCS from experts achieved a score of 90%, which was included in the very valid category and suitable for use in learning. The practicality of the STM based on SSCS as shown by the implementation of learning during two meetings with a percentage of 93% and included in the very good category, student response reached 81.2% with very good criteria, and student activity with a percentage of 85.5% with good criteria. The effectiveness of the STM based on SSCS is shown by the results of the analysis of learning outcomes tests by obtaining N-Gain values 0.78 with high criteria. Thus, it is concluded that the concept of STM based on SSCS in the living things classification concept has valid, practical, and effective criteria. The research of STM based on SSCS is expected to be developed in other material concepts.

This study explores the development prospects of tourism in predominantly industrial small-sized cities (SSCs), focusing on the integration of tourism into urban planning and sustainable practices. Using structural equation modeling (SEM) to analyze survey data from SSCs in Serbia and Russia, the research identifies key factors contributing to urban tourism sustainability. The analysis reveals the significant roles of environmental, economic, social, and cultural indicators in promoting sustainable urban tourism. The importance of inclusive development and community engagement is also highlighted, underscoring their impact on sustainability. The findings offer theoretical insights and practical recommendations for effectively incorporating tourism into urban planning to achieve comprehensive sustainability in SSCs. [ABSTRACT FROM AUTHOR]

Electronic student worksheets (e-worksheet) are needed as alternative teaching materials in learning. This study aims to produce teaching materials in the form of e-worksheet based on Search Solve Create and Share (SSCS) Islamic context to improve science process skills on class XI excretory system material that is worthy of the results of validity, responses of students and biology teachers. This research was conducted at MAN 1 Bogor. The research model used is a 4D model (Define, Design, Develop, Disseminate), but in research only to the development stage (Develop). The e-worksheet teaching materials developed are tested for validity. The results of validity tests by design and media experts obtained 89% in the very decent category, material expert assessments obtained 84% in the very feasible categories, and expert assessments of Islamic religious education obtained 100% in the very feasible categories. The results of student responses obtained percentages of 89% in limited trials and 89.7% in expanded trials. Based on the findings of the research results, it can be concluded that E e-worksheet based on Search Solve, Create and Share (SSCS), an Islamic context to improve science process skills on the excretory system material developed, is very feasible to be used and applied to biology learning. [ABSTRACT FROM AUTHOR]

It is critical to develop the methods and technologies of studying the species and concentration in the processing of adsorption, and diffusion of some important radionuclides in spent fuel waste processing such as Beishan granites in domestic institutions and universities for the geological disposal of high-level radioactive wastes. Enrich the models used or constructed and the calculation procedures developed in the past two decades in this field. In order to evaluate the safety of the repository, chemical speciation analysis of nuclides is the premise of research to accurately predict the migration behavior of nuclides. In view of the rapid development of China's nuclear energy industry and the need to establish the identification of nuclides in the environment, it is of great significance to carry out the study of the chemical forms of nuclides around the repository in China. Aiming at the research requirements of element speciation distribution in the environment, a set of B/S architecture element speciation distribution simulation software is developed with JAVA as the development tool, MySQL as the database, and Tomcat as the container. In order to solve the convergence problem of chemical reaction equilibrium nonlinear equations encountered in simulation calculation, the method based on chemical reaction potential energy is introduced to solve the chemical reaction nonlinear equations quickly, and the multi-phase equilibrium calculation can be expanded. SSCS was used to study the species of U in groundwater and the effects of Eh, pH, different ions and concentrations. The calculation results indicate that neptunium mainly exists as NpO2CO-3(aq) in groundwater. Under strong acidic conditions, neptunium maily exists as NpO+2(aq), while in weak acidic, neutral or weak alkaline conditions, the main species are NpO+2(aq) and NpO2OH.When the solution is in strong alkaline conditions, the species are complicated most of neptunium exists as NpO2(CO3)-3(aq), with the possible generation of NpO2(CO3)3-2 or NpO2(CO3)5-3. Np(Ⅴ) is stable in the reduction condition, while Np(Ⅳ) and Np(Ⅵ) are the possible generation. Comparing the neptunium calculation results of the software in the environment with the PHREEQC calculation results, the relative error is within 10 %. For the distribution of trace elements in the environment, a theoretical calculation solution is provided.

Purpose: The purpose of this study was to screen the genes and pathways that are involved in spermatogonia stem cell (SSC) differentiation regulation during the transition from Aundiff to A1. Methods: RNA sequencing was performed to screen differentially expressed genes at 1 d and 2 d after SSC differentiation culture. KEGG pathway enrichment and GO function analysis were performed to reveal the genes and pathways related to the initiation of early SSC differentiation. Results: The GO analysis showed that Rpl21, which regulates cell differentiation initiation, significantly increased after 1 day of SSC differentiation. The expressions of Fn1, Cd9, Fgf2, Itgb1, Epha2, Ctgf, Cttn, Timp2 and Fgfr1, which are related to promoting differentiation, were up-regulated after 2 days of SSC differentiation. The analysis of the KEGG pathway revealed that RNA transport is the most enriched pathway 1 day after SSC differentiation. Hspa2, which promotes the differentiation of male reproductive cells, and Cdkn2a, which participates in the cell cycle, were significantly up-regulated. The p53 pathway and MAPK pathway were the most enriched pathways 2 days after SSC differentiation. Cdkn1a, Hmga2, Thbs1 and Cdkn2a, microRNAs that promote cell differentiation, were also significantly up-regulated. Conclusions: RNA transport, the MAPK pathway and the p53 pathway may play vital roles in early SSC differentiation, and Rpl21, Fn1, Cd9, Fgf2, Itgb1, Epha2, Ctgf, Cttn, Timp2, Fgfr1, Hspa2, Cdkn2a, Cdkn1a, Hmga2 and Thbs1 are involved in the initiation of SSC differentiation. The findings of this study provide a reference for further revelations of the regulatory mechanism of SSC differentiation. [ABSTRACT FROM AUTHOR]

Spermatogonial stem cells (SSCs) play a crucial role in mammalian spermatogenesis and maintain the stable inheritance of the germline in livestock. However, stress and bacterial or viral infections can disrupt immune homeostasis of the testes, thereby leading to spermatogenesis destruction and infertility, which severely affects the health and productivity of mammals. This study aimed to explore the effect of ubiquitin C-terminal hydrolase L1 (UCHL1) knockdown (KD) in goat SSCs and mouse testes and investigate the potential anti-inflammatory function of UCHL1 in a poly(I:C)-induced inflammation model to maintain microenvironmental homeostasis. In vitro, the downregulation of UCHL1 (UCHL1 KD) in goat SSCs increased the expression levels of apoptosis and inflammatory factors and inhibited the self-renewal and proliferation of SSCs. In vivo, the structure of seminiferous tubules and spermatogenic cells was disrupted after UCHL1 KD, and the expression levels of apoptosis- and inflammation-related proteins were significantly upregulated. Furthermore, UCHL1 inhibited the TLR3/TBK1/ IRF3 pathway to resist poly(I:C)-induced inflammation in SSCs by antagonizing HSPA8 and thus maintaining SSC autoimmune homeostasis. Most importantly, the results of this study showed that UCHL1 maintained immune homeostasis of SSCs and spermatogenesis. UCHL1 KD not only inhibited the self-renewal and proliferation of goat SSCs and spermatogenesis but was also involved in the inflammatory response of goat SSCs. Additionally, UCHL1 has an antiviral function in SSCs by antagonizing HSPA8, which provides an important basis for exploring the specific mechanisms of UCHL1 in goat spermatogenesis. [ABSTRACT FROM AUTHOR]

The testis is vulnerable to ionizing radiation, sexual dysfunction and male infertility are common problems after local radiation or whole-body exposure. Currently, there are no approved drugs for the prevention or treatment of radiation testicular injury. Sulforaphane (SFN) is an indirect antioxidant that induces phase II detoxification enzymes and antioxidant genes. Herein, we investigated the radiation protective effect of SFN on testicular injury in mice and its potential mechanism. Mice were randomly divided into blank control group (Ctrl), radiation + no pretreatment group (IR), and radiation + SFN groups (IRS). In the radiation + SFN groups, starting from 72 h before radiation, SFN solution was intraperitoneally injected once a day until they were sacrificed. Mice in the blank control group and the radiation + no pretreatment group were simultaneously injected intraperitoneally with an equal volume of the solvent used to dissolve SFN (PBS with a final concentration of 0.1%DMSO) until they were sacrificed. They were subjected to 6Mev-ray radiation to the lower abdominal testis area (total dose 2Gy). Twenty-four hours after radiation, six mice in each group were randomly sacrificed. Seventy-two hours after radiation, the remaining mice were sacrificed. The results showed that the harmful effects of ionizing radiation on testes were manifested as damage to histoarchitecture, increased oxidative stress, and apoptosis, and thus impaired male fertility. SFN injections can reverse these symptoms. The results showed that SFN can improve the damage of mouse testis caused by irradiation. Furthermore, SFN prevents spermatogenesis dysfunction caused by ionizing radiation by activating Nrf2 and its downstream antioxidant gene. [ABSTRACT FROM AUTHOR]

Electronic student worksheets (e-worksheet) are needed as alternative teaching materials in learning. This study aims to produce teaching materials in the form of e-worksheet based on Search Solve Create and Share (SSCS) Islamic context to improve science process skills on class XI excretory system material that is worthy of the results of validity, responses of students and biology teachers. This research was conducted at MAN 1 Bogor. The research model used is a 4D model (Define, Design, Develop, Disseminate), but in research only to the development stage (Develop). The e-worksheet teaching materials developed are tested for validity. The results of validity tests by design and media experts obtained 89% in the very decent category, material expert assessments obtained 84% in the very feasible categories, and expert assessments of Islamic religious education obtained 100% in the very feasible categories. The results of student responses obtained percentages of 89% in limited trials and 89.7% in expanded trials. Based on the findings of the research results, it can be concluded that E e-worksheet based on Search Solve, Create and Share (SSCS), an Islamic context to improve science process skills on the excretory system material developed, is very feasible to be used and applied to biology learning.

Water pollution from manufacturing waste and air pollution from forest and land fires are major environmental issues in the Siak district. This research aimed at gathering empirical data by implementing a real-action project based on SSCS learning to enhance sustainability awareness of Junior High School. This quasi-experiment was carried out in two groups of students in 7th grade of SMPN 1 Koto Gasib, Siak, Riau Province. The experimental class used the SSCS learning model with the ESD approach and the control class applied the scientific learning model. Indicators of sustainability awareness comprise: 1) Sustainability Practice Awareness; 2) Behavioral and Attitude Awareness; and 3) Emotional Awareness. Real-action project that is implemented by the teacher in this research is conducted to promote sustainability awareness in the form of a water purification model, planting pollution-absorbing plants, and creating Eco-brick flower pots. Data analysis uses inferential statistics, namely the T-test using SPSS-26 software. The analysis results of sustainability awareness indicate that students in the experimental class get a higher average of 76%, with the high category. Meanwhile, students in the control class get an average of 65% in the medium category. The T-test analysis of sustainability awareness gets a significance value of 0,002.= 0,05, which indicates that there is a significant difference between experimental and control classes. The implementation of SSCS learning model using ESD approach can enhance the students' sustainability awareness through environmental problem-solving activities, as well as building knowledge, behavior, and attitudes of love for the environment. [ABSTRACT FROM AUTHOR]

Water pollution from manufacturing waste and air pollution from forest and land fires are major environmental issues in the Siak district. This research aimed at gathering empirical data by implementing a real-action project based on SSCS learning to enhance sustainability awareness of Junior High School. This quasi-experiment was carried out in two groups of students in 7th grade of SMPN 1 Koto Gasib, Siak, Riau Province. The experimental class used the SSCS learning model with the ESD approach and the control class applied the scientific learning model. Indicators of sustainability awareness comprise: 1) Sustainability Practice Awareness; 2) Behavioral and Attitude Awareness; and 3) Emotional Awareness. Real-action project that is implemented by the teacher in this research is conducted to promote sustainability awareness in the form of a water purification model, planting pollution-absorbing plants, and creating Eco-brick flower pots. Data analysis uses inferential statistics, namely the T-test using SPSS-26 software. The analysis results of sustainability awareness indicate that students in the experimental class get a higher average of 76%, with the high category. Meanwhile, students in the control class get an average of 65% in the medium category. The T-test analysis of sustainability awareness gets a significance value of 0,002. 0,05, which indicates that there is a significant difference between experimental and control classes. The implementation of SSCS learning model using ESD approach can enhance the students’ sustainability awareness through environmental problem-solving activities, as well as building knowledge, behavior, and attitudes of love for the environment.

Hollow spherical WO 3 powder was prepared from mixed solution of ammonium metatungstate, glycine and ammonium nitrate by spray solution combustion synthesis (SSCS) method. The effects of fuel ratio, temperature, precursor solution concentration on the structure and morphology of as-prepared powder, and the SSCS mechanism have been discussed in detail. When precursor solution concentration is 0.10 mol/L, in which the fuel ratio is 2, and reaction temperature set to be 800 °C, the spherical WO 3 powder with smooth surface and a median diameter of 24.02 μm can be obtained, which consists of particles with a diameter of about 30 nm, and the specific surface area is 13.5 m2/g. Moreover, the as-synthesized WO 3 powder is applied to degrade RhB solution in visible light to evaluate its catalytic performance by PLS-SXE300/300UV. Only 10 mg powder can degrade 70.1% RhB solution within 2 h. [ABSTRACT FROM AUTHOR]

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Spermatogonial stem cells (SSCs) are a small group of testicular cells located in the basement membrane of seminiferous tubules and can balance self-renewal and differentiation during spermatogenesis. Our in vitro culture experiments of mouse SSCs indicated heterogeneity of cultured cells. Highly compact colonies were observed next to SSC colonies, which we call clump cells. We used immunocytochemical staining to identify SSCs and somatic cells with VASA and Vimentin antibodies. Subsequently, we compared mRNA expression levels of VASA, DAZL, PLZF, GFRA1, Lin28, Kit, Myc and Vimentin genes using Fluidigm real-time RT-polymerase chain reaction in clump cells, SSCs, and testicular stromal cells. To better understand the functions of selected genes, we created a protein–protein interaction network and performed an enrichment analysis using different databases. Based on the data collected, we state that clump cells do not express the molecular markers of SSCs, so we cannot consider them as SSCs; however, we claim that these cells are altered SSCs. The molecular mechanism of this conversion is still obscure. Therefore, this study can support the analysis of germ cell development both in vitro and in vivo. In addition, it can be effective in finding new and more efficient treatments for male infertility. [ABSTRACT FROM AUTHOR]

الأهداف: هدفت الدراسة الحالية الى التعرف على فاعلية النموذج التعليمي (SSCS )في تحسين التفكير التأملي في الرياضيات لدى طلبة الصف العاشر. المنهجية: استخدامت الدراسة المنهج شبه التجريبي بقياس قبلي و بعدي وتكونت عينة الدراسة من(40) طالبة وزعوا بالتساوي على مجموعتي الدراسة الضابطة والتجريبية، ولتحقيق أهداف الدراسة تم بناء اختبار التفكير التأملي بمهاراته الخمسة (التأمل والملاخظة،الكشف عن المغالطات، الوصول الى استنتاجات، إعطاء تفسيرات مقنعة، وضع حلول مقترحة)، وتم التحقق من صدقه وثباته. النتائج: أظهرت نتائج الدراسة وجود فروق ذات دلالة إحصائية بين المتوسطات الحسابية لأداء طلبة المجموعتين التجريبية والضابطة في كل مهارة من مهارات التفكير التأملي منفردة وعلى اختبار التفكير التأملي الكلي تعزى لطريقة التدريس ولصالح المجموعة التجريبية. الخلاصة: وفي ضوء نتائج الدراسة يوصي الباحثون بضرورة توظيف النموذج التعليمي(SSCS) في تدريس الرياضيات لطلبة الصف العاشر.

This study aims to develop a mathematics learning tool consisting of a Learning Implementation Plan (RPP), Student Worksheet (LKS), and a Computational Thinking Test (CT Test) using the Search, Solve, Create, and Share (SSCS) learning model with a Realistic approach. Mathematics Education (RME) which is valid, practical and effective and examines its effect on the computational thinking ability of junior high school students. This research combines development research (R&D) and experimental research. Data collection techniques in this study used interviews, observation of student activities, observation of the implementation of learning devices, student response questionnaires, and learning outcomes tests in the form of CT tests. The results showed that the learning tools met the criteria of being valid, practical, and effective. The validity coefficients for lesson plans, worksheets, and CT tests were 3.80, respectively; 3.80; and 3.81. The value of practicality seen from the results of observations of the implementation of learning devices is in the very practical category with a percentage of 98%. The value of the effectiveness of learning tools shows that 92% of students are active, 98% of students respond positively to learning, and 77% of students complete learning. Based on the t-test on the results of experimental research, it was found that the SSCS model learning device with the RME approach had a significant effect on students' computational thinking abilities.

ABSTRACT: Spermatogonia Stem Cells (SSCs) are the basis of spermatogenesis. In the poultry industry, asthenospermia and azoospermia in roosters seriously reduce economic benefits. In this study, we explored SSCs formation mechanisms in detail. TDRD1, which is a downstream target gene of TCF7L2 and is modified by histone methylation, was screened through multiomics analysis. Functionally, RT-qPCR, flow cytometry, immunohistochemistry, and indirect immunofluorescence results showed that H3K4me2 regulated TDRD1 to promote SSCs formation both in vivo and in vitro. Furthermore, ChIP-qPCR and dual luciferase assays showed that H3K4me2 was enriched in the −800 to 0 bp region of the TDRD1 promoter and positively regulated TDRD1 transcription to promote SSCs formation. Interestingly, in mechanistic terms, dual luciferase assays showed that TDRD1 transcription levels were significantly decreased after co-transfection with dCas9-LSD1-P1/P2/P3 and OETCF7L2, while TDRD1 transcript levels were not significantly altered after transfecting dCas9-LSD1-P4 and OETCF7L2. These results suggested that H3K4me2 enrichment in P1, P2, and P3 of the TDRD1 promoter promotes TDRD1 transcription by reducing enrichment of TCF7L2. This study explored the specific regulatory mechanisms involving the Wnt signaling pathway, H3K4me2, and TDRD1, enriched the regulatory network regulating the formation of SSCs, and laid a theoretical foundation for the specific application of SSCs.

The production of germ cells in vitro would open important new avenues for stem biology and human medicine, but the mechanisms of germ cell differentiation are not well understood. The chicken, as a great model for embryology and development, was used in this study to help us explore its regulatory mechanisms. In this study, we reported a comprehensive genome-wide DNA methylation landscape in chicken germ cells, and transcriptomic dynamics was also presented. By uncovering DNA methylation patterns on individual genes, some genes accurately modulated by DNA methylation were found to be associated with cancers and virus infection, e.g., AKT1 and CTNNB1. Chicken-unique markers were also discovered for identifying male germ cells. Importantly, integrated epigenetic mechanisms were explored during male germ cell differentiation, which provides deep insight into the epigenetic processes associated with male germ cell differentiation and possibly improves treatment options to male infertility in animals and humans.

XBP1 is a transcription factor that plays a central role in controlling cellular responses to endoplasmic reticulum stress (ERS). Under stress conditions, the transcriptionally active form of XBP1 is generated by splicing of XBP1 mRNA by the ER-resident protein inositol-requiring enzyme-1α (IRE1α). This study aimed to investigate the role of XBP1 in male reproductive disorders. XBP1s-overexpressing goat spermatogonial stem cells (gSSCs) showed higher proliferative ability in vitro and in vivo. These cells also showed higher antioxidant capacity. In comparison, XBP1 knockdown significantly suppressed proliferation. Further analysis showed that XBP1 could stimulate the secretion of IL-6 from macrophages. Overall, the results indicate that XBP1s functions to enhance the proliferation ability and antioxidant capacity of gSSCs, potentially through a mechanism involving the regulation of gSSCs by macrophages. • The male reproductive dysfunction caused by LPS mainly damages germ cells except for spermatogonial stem cells (SSCs). • XBP1 was highly expressed in SSCs in LPS model. • The XBP1s-overexpressing gSSC (goat spermatogonial stem cell) presents the higher proliferative ability in vitro and in vivo. • XBP1 also affected the SSC by regulating the secretion of macrophages IL-6. [ABSTRACT FROM AUTHOR]

Detailed analysis of the regulatory mechanism of spermatogonia stem cell (SSCs) genesis can provide a novel strategy for the application of SSCs in the fields of transgenic animal production and regenerative medicine. Previous studies in this study showed that WNT signaling can positively regulate the formation of SSCs, but the exact regulatory mechanism is not clear. Here, we predicted the target gene of the Wnt/TCF7L2 pathway, namely TDRD1, by bioinformatics analysis. Functional studies revealed that overexpression of TDRD1 during RA‐induced SSCs formation in vitro significantly upregulated the expression of reproductive marker genes (Integrinβ1 and Integrinα6), and further flow cytometric analysis also confirmed that the formation efficiency of SSCs was significantly increased after overexpression of TDRD1; while interference with TDRD1 showed the exact opposite result. The in vivo experiments were consistent with the results of the in vitro experiments. Interestingly, although Wnt/TCF7L2 can promote the formation of SSCs, its function must be dependent on the expression of TDRD1, which was also repeatedly demonstrated as a target gene of the Wnt/TCF7L2 signaling pathway. Mechanistically, we found a large number of CpG sites in the TDRD1 promoter, and BSP analysis also confirmed that DNA methylation modifications in the TDRD1 promoter were significantly higher in embryonic stem cells than in SSCs, and further dual‐luciferase reporter system assays revealed that low DNA methylation modification levels could enhance TDRD1 promoter activity; although previous studies demonstrated that TCF7L2 could enrich in the TDRD1 promoter region, the binding of the two was dependent on low DNA methylation modification. Taken together, we confirmed that low DNA methylation mediates Wnt/TCF7L2 regulation of TDRD1 to promote the formation of SSCs, providing a basis for SSCs in improving animal productivity. [ABSTRACT FROM AUTHOR]

Objectives: Systemic lupus erythematosus (SLE) is a systemic autoimmune disease associated with neuro-psychiatric (NP) manifestations. Frequency and patterns of neuro-psychiatric systemic lupus erythematosus (NPSLE) vary substantially between patients. We conducted a systematic review (SR) of the literature and examined prevalence and characteristics of NPSLE in the Swiss SLE cohort study (SSCS). Methods: The SR search was performed between January 1999 and January 2020. We included prospective/cross-sectional studies focusing on NPSLE. We secured study characteristics, cohort compositions and frequencies of NP manifestations, assessed heterogeneity across reports and investigated sources of variation using meta-regression models. Regarding the SSCS, we reviewed all patients included and classified NP manifestations. Results: The SR searches identified 530 studies. We included 22 studies in our meta-analysis, the mean frequency of NPSLE ranged from 10.6% to 96.4%. The frequency of NPSLE in the SSCS was 28.1%. Severe events including cerebrovascular insults, seizures and psychosis appeared in 7.1%, 5.3% and 6.5% respectively. There was a linear relationship between duration of SLE and cumulative incidence of NPSLE. Conclusions: The spectrum of NPSLE is very broad. The diagnostic work-up and rates of reported manifestations varied substantially across studies. We call for concerted efforts and consensus regarding definitions of NPSLE that will facilitate accurate diagnosis and attribution to SLE, particularly with a view to timely intervention and patient outcomes. [ABSTRACT FROM AUTHOR]

Background: Ets variant factor 5 (ETV5) plays an important regulatory role in mouse spermatogonial stem cells (SSCs) self-renewal. ETV5 knockout (KO) mice exhibit a progressive loss of SSCs and resulting in a sertoli cell-only phenotype. The current study was aimed to use gene editing technology to obtain ETV5-KO pigs as a model for studying the apoptosis mechanism of SSCs and further clarify the function of ETV5 gene in pigs. Methods: A gene editing plasmid for the porcine ETV5 gene was constructed, transfected into porcine fetal fibroblasts by electroporation to obtain ETV5-KO cells. ETV5-KO cells were used as donors to prepare ETV5-KO pigs by somatic cell nuclear transfer (SCNT). Testis tissues were collected for hematoxylin and eosin (HE), immunohistochemistry (IHC), RT-PCR testing and blood for ELISA testing from ETV5-KO pig. Result: In the present study, we used the CRISPR/Cas9 system and SCNT to genrate homozygous ETV5-KO pigs. We observed 3 phenotypes in these pigs: normal testis development after birth, the SSCs in the seminiferous tubules did not show obviously extinction at sexual maturity and normal spermatogenesis. [ABSTRACT FROM AUTHOR]

Abstract Background High temperature has a very adverse effect on mammalian spermatogenesis and eventually leads to sub- or infertility through either apoptosis or DNA damage. However, the direct effects of heat stress on the development of spermatogonial stem cells (SSCs) are still unknown because SSCs are rare in the testes. Methods In the present study, we first used in vitro-cultured SSCs to study the effect of heat shock treatment on SSC development. Then, we used RNA-Seq analysis to identify new genes or signalling pathways implicated in the heat stress response. Results We found that 45 min of 43 °C heat shock treatment significantly inhibited the proliferation of SSCs 2 h after treatment but did not lead to apoptosis. In total, 17,822 genes were identified by RNA-Seq after SSC heat shock treatment. Among these genes, we found that 200 of them had significantly changed expression, with 173 upregulated and 27 downregulated genes. The number of differentially expressed genes in environmental information processing pathways was 37, which was the largest number. We screened the candidate JAK-STAT signalling pathway on the basis of inhibition of cell cycle progression and found that the JAK-STAT pathway was inhibited after heat shock treatment. The flow cytometry results further confirmed that heat stress caused S phase cycle arrest of SSCs. Conclusion Our results showed that heat shock treatment at 43 °C for 45 min significantly inhibited SSC self-renewal through S phase cell cycle arrest but not apoptosis.

HT-2 toxin is widely found in moldy crops and is the major metabolite of T-2 toxin, which has been shown to exert various toxic effects in farm animals. However, little is known about the effects of HT-2 toxin on male reproduction, particularly spermatogenesis. This study aims to investigate the toxic effects of HT-2 toxin on goat spermatogonial stem cells (SSCs) and related autophagy-regulated mechanisms. Our results showed that HT-2 toxin exposure resulted in decreased cell viability and proliferation, disrupted SSCs self-renewal, and reduced germ cell-related gene expression. HT-2 toxin exposure also induced oxidative stress and cell apoptosis, as shown by ROS accumulation, increased antioxidant enzyme activity levels, decreased the mitochondrial membrane potential, and increased caspase-9 mRNA and Bcl/bax protein levels. Additionally, HT-2 toxin exposure increased the expression of the autophagy-inducing genes Atg5 , Atg7 and Beclin1 and the number of autophagosomes, which indicated that HT-2 toxin induced autophagy in the goat SSCs. Moreover, we also examined a possible mechanism by which HT-2 toxin exposure induced higher expression of AMPK, mTOR and ULK at both the mRNA and protein levels. our results indicated that HT-2 toxin caused apoptosis and autophagy by activating AMPK-mTOR-ULK1 pathway, which further affected SSCs viability. • HT-2 toxin exposure affects cell viability and renewal of goat SSCs. • HT-2 toxin exposure induces cell apoptosis and autophagy. • HT-2 toxin exposure activates AMPK-mTOR-ULK1 pathway in goat SSCs. [ABSTRACT FROM AUTHOR]

Bone possesses a remarkable repair capacity to regenerate completely without scar tissue formation. This unique characteristic, expressed during bone development, maintenance and injury (fracture) healing, is performed by the reparative cells including skeletal stem cells (SSCs) and their descendants. However, the identity and functional roles of SSCs remain controversial due to technological difficulties and the heterogeneity and plasticity of SSCs. Moreover, for many years, there has been a biased view that bone marrow is the main cell source for bone repair. Together, these limitations have greatly hampered our understanding of these important cell populations and their potential applications in the treatment of fractures and skeletal diseases. Here, we reanalyse and summarize current understanding of the reparative cells in bone regeneration and repair and outline recent progress in this area, with a particular emphasis on the temporal and spatial process of fracture healing, the sources of reparative cells, an updated definition of SSCs, and markers of skeletal stem/progenitor cells contributing to the repair of craniofacial and long bones, as well as the debate between SSCs and pericytes. Finally, we also discuss the existing problems, emerging novel technologies and future research directions in this field. [ABSTRACT FROM AUTHOR]

The purposes of this study was to know wether the student’s problem solving ability on SSCS and PBL learning models achive the mastery learning ; to compare the the student’s problem solving ability on SSCS and PBL learning models; to describe the problem solving ability student on SSCS learning model viewed from geometry thinking levels, and to know the quality of SSCS learning models. The method used was a mixed method. The population of this study was all students of SMP N 10 Semarang. The sample was chooseb by simple random sampling technique and class VII D as control class and VII G as experiment class.The quantitative data was analyzed by z-test to and the equivalence of two means. The qualitative data was analyzed through the validity test, data display, data reduction, and conclusion . Results indicated that either SSCS and PBL learning models have achieve the mastery learning of poblem solving ability test but there was no difference between students' problem solving abilitiy in the SSCS and PBL learning models. Students with PreRecognition and Visual can’t fully identify the properties of figure so it makes difficulty in solving problem. Students with Analysis level solve problem using the properties of certain figures.

Reproductive health of men has declined in recent past with reduced sperm count and increased incidence of infertility and testicular cancers mainly attributed to endocrine disruption in early life. Present study aims to evaluate whether testicular stem cells including very small embryonic-like stem cells (VSELs) and spermatogonial stem cells (SSCs) get affected by endocrine disruption and result in pathologies in adult life. Effect of treatment on mice pups with estradiol (20 μg on days 5–7) and diethylstilbestrol (DES, 2 μg on days 1–5) was studied on VSELs, SSCs and spermatogonial cells in adult life. Treatment affected spermatogenesis, tubules in Stage VIII & sperm count were reduced along with reduction of meiotic (4n) cells and markers (Prohibitin, Scp3, Protamine). Enumeration of VSELs by flow cytometry (2–6 μm, 7AAD-, LIN-CD45-SCA-1+) and qRT-PCR using specific transcripts for VSELs (Oct-4a, Sox-2, Nanog, Stella, Fragilis), SSCs (tOct-4, Gfra-1, Gpr-125) and early germ cells (Mvh, Dazl) showed several-fold increase but transition from c-Kit negative to c-Kit positive spermatogonial cells was blocked on D100 after treatment. Transcripts specific for apoptosis (Bcl2, Bax) remained unaffected but tumor suppressor (p53) and epigenetic regulator (NP95) transcripts showed marked disruption. 9 of 10 mice exposed to DES showed tumor-like changes. To conclude, endocrine disruption resulted in a tilt towards excessive self-renewal of VSELs (leading to testicular cancer after DES treatment) and blocked differentiation (reduced numbers of c-Kit positive cells, meiosis, sperm count and fertility). Understanding the underlying basis for infertility and cancer initiation from endogenous stem cells through murine modelling will hopefully improve human therapies in future. [ABSTRACT FROM AUTHOR]

Theroretically, servitization benefits industrial companies to generate more revenue, integrate themselves deeper into the value chains of their customers and improves the competitiveness. The ongoing digital transformation can enable servitization towards more advanced services with a more customer centric view. Macro economically, the industrial sector is very important for most of the developed countries. The digital transformation is posing a triple challenge to the machining and equipment manufacturers and will require a continued development of the existing business models, a change of organizational structures and a strong leadership to remain successful. The companies will need to reevaluate their market justification and define their value proposition to both existing and potentially new customers. New skills are required as data and analytics, represented by IIoT and AI, will play an ever-larger role in the companies' interaction with their present and new customers. For the industrial companies, servitization is both linked to higher risk and to a higher earnings potential. Implications for Central European audience: The implications for Central European industrial companies of the ongoing digitalisation and servitization will be profound. The European car industry is undergoing significant changes and not only due to E-mobility. Also Products-as-Service will have an impact on their whole value chain. The industrial sector in general and the machining industry in particular will need to re-assess its business models and revenue generation. In addition, senior management is already confronted with the need for both new skill-sets and possibly more agile organisational structures, where the industrial mind-set will be challenged by new service models and the thinking of the digital natives. [ABSTRACT FROM AUTHOR]

Background: Spermatogonial stem cells (SSCs) are undifferentiated cells which are highly reproducible and expandable. Several studies have been conducted to reproduce these cells in culture. They used growth factors, hormones and different feeder cells to improve survival and proliferation of SSCs. Objective: This study was conducted to evaluate the effects of follicular stimulating hormone (FSH) on gene expression of fibroblast growth factor (FGF2) and glial cell-derived neurotrophic factor (GDNF) in Sertoli cells. Materials and Methods: Sertoli cells and SSCs were isolated from 3-5 month-old calves. Bovine testicular cells were cultured for 15 days with or without FSH. Identification of these cells was confirmed by immunocytochemistry analysis. Colony formation of SSCs was evaluated using an inverted microscope. The gene expression of FGF2 and GDNF and the gene markers bcl6b, thy-1, and C-kit were evaluated using the quantitative RT-PCR technique. Results: The results indicated that FSH increased colonization of SSCs. the expression of GDNF, FGF2, and markers of undifferentiated spermatogonia was increased following culture in control and FSH groups (p

This study aims to determine the condition factors influencing the in vitro proliferation culture of spermatogonial stem cells (SSCs) through isolation and culture of SSCs. With mouse embryonic fibroblast (MEF) cells, SIM-6-thiogunanie-oualiain (STO) cells and Hela cells used as the feeder layers, we compared the numbers of cell clones treated with mitomycin C as well as the proliferation conditions with and without the treatment with trypsin. In the culture solution, we respectively added serum and vitamin C (of different concentrations, VC) to culture goat SSCs; furthermore, we tested their pro-proliferation effect on goat SSCs and its mechanism. We determined that one-month-old goats were the most suitable for the in vitro culture; 1.5 h, 2.5 h and 2.5 h were respectively the most suitable treatment times in the feeder layers of MEF cells, STO cells and Hela cells; 2.5% was the optimal serum concentration; VC (30 μg/mL) had a promoting effect on the in vitro culture of goat SSCs. We conclude that the age of goats, different feeding layers and their preparation conditions, serum concentrations and VC concentrations are the condition factors influencing the in vitro culture and proliferation of SSCs.

Spermatogonial stem cells (SSCs) play a crucial role in mammalian spermatogenesis and maintain the stable inheritance of the germline in livestock. However, stress and bacterial or viral infections can disrupt immune homeostasis of the testes, thereby leading to spermatogenesis destruction and infertility, which severely affects the health and productivity of mammals. This study aimed to explore the effect of ubiquitin C-terminal hydrolase L1 (UCHL1) knockdown (KD) in goat SSCs and mouse testes and investigate the potential anti-inflammatory function of UCHL1 in a poly(I:C)-induced inflammation model to maintain microenvironmental homeostasis. In vitro, the downregulation of UCHL1 (UCHL1 KD) in goat SSCs increased the expression levels of apoptosis and inflammatory factors and inhibited the self-renewal and proliferation of SSCs. In vivo, the structure of seminiferous tubules and spermatogenic cells was disrupted after UCHL1 KD, and the expression levels of apoptosis- and inflammation-related proteins were significantly upregulated. Furthermore, UCHL1 inhibited the TLR3/TBK1/IRF3 pathway to resist poly(I:C)-induced inflammation in SSCs by antagonizing HSPA8 and thus maintaining SSC autoimmune homeostasis. Most importantly, the results of this study showed that UCHL1 maintained immune homeostasis of SSCs and spermatogenesis. UCHL1 KD not only inhibited the self-renewal and proliferation of goat SSCs and spermatogenesis but was also involved in the inflammatory response of goat SSCs. Additionally, UCHL1 has an antiviral function in SSCs by antagonizing HSPA8, which provides an important basis for exploring the specific mechanisms of UCHL1 in goat spermatogenesis., (© 2023 Federation of American Societies for Experimental Biology.)

Abstract: Problem-solving skills are important for students to cope with rapid changes in society and supported by technological advances. Problem-solving skills that students have especially in Newton's Law materials need to be improved so that it becomes like an expert problem solver. Therefore, SSCS problem solving research with CPS is done to determine its effect on problem solving skills. This research uses one group pretest-posttest design. The results showed that the learning model has an influence on problem-solving skills with strong effectiveness, but the improvement of problem solving skills is still low. Abstrak: Keterampilan pemecahan masalah merupakan hal yang penting dimiliki siswa untuk menghadapi perubahan masyarakat yang cepat dan didukung oleh kemajuan teknologi. Keterampilan pemecahan masalah yang dimiliki siswa khususnya pada materi Hukum Newton perlu ditingkatkan sehingga menjadi seperti pemecah masalah ahli. Oleh sebab itu, dilakukan penelitian SSCS problem solving disertai CPS untuk mengetahui pengaruhnya terhadap keterampilan pemecahan masalah. Penelitian ini menggunakan one group pretest-posttest design. Hasil penelitian menunjukkan bahwa model pembelajaran tersebut memiliki pengaruh terhadap keterampilan pemecahan masalah dengan tingat efektivitas yang kuat, namun peningkatan keterampilan pemecahan masalah masih tergolong rendah.

Spermatogonial stem cells (SSCs) renew themselves throughout the life of an organism and also differentiate into sperm in the adult. They are multipopent and therefore, can be induced to differentiate into many cells types in vitro. SSCs from pigs, considered an ideal animal model, are used in studies of male infertility, regenerative medicine, and preparation of transgenic animals. Here, we report on a culture system for porcine SSCs and the differentiation of these cells into neuron-like cells and adipocytes. SSCs and Sertoli cells were isolated from neonatal piglet testis by differential adhesion and SSCs were cultured on a feeder layer of Sertoli cells. Third-generation SSCs were induced to differentiate into neuron-like cells by addition of retinoic acid, β-mercaptoethanol, and 3-isobutyl-1-methylxanthine (IBMX) to the induction media and into adipocytes by the addition of hexadecadrol, insulin, and IBMX to the induction media. The differentiated cells were characterized by biochemical staining, qRT-PCR, and immunocytochemistry. The cells were positive for SSC markers, including alkaline phosphatase and SSC-specific genes, consistent with the cells being undifferentiated. The isolated SSCs survived on the Sertoli cells for 15 generations. Karyotyping confirmed that the chromosomal number of the SSCs were normal for pig (2n = 38, n = 19). Pig SSCs were successfully induced into neuron-like cells eight days after induction and into adipocytes 22 days after induction as determined by biochemical and immunocytochemical staining. qPCR results also support this conclusion. The nervous tissue markers genes, Nestin and β-tubulin, were expressed in the neuron-like cells and the adipocyte marker genes, PPARγ and C/EBPα, were expressed in the adipocytes.

Siswa cenderung merasa kesulitan dalam memahami materi pecahan sehingga tingkat berpikir kreatif atau karakter rasa ingin tahu siswa pada materi ini relativ rendah. Untuk memberikan solusi dari permasalahan tersebut, dikembangkanlah perangkat pembelajaran model SSCS berbantuan media puzzle. Tujuan penelitian ini adalah untuk mendeskripsikan berpikir kreatif matematis dan rasa ingin tahu siswa sebelum pembelajaran, mengetahui keefektifan penerapan model pembelajaran, dan mendeskripsikan berpikir kreatif matematis dan rasa ingin tahu siswa kelas IV setelah pembelajaran SSCS berbantuan media puzzle pada materi pecahan. Hasil penelitian pengembangan perangkat pembelajaran model SSCS berbantuan media puzzle ini adalah (1) perangkat pembelajaran yang dikembangkan valid, silabus dengan skor rata-rata 3,82 (baik), RPP dengan skor 3,95 (baik); LKS dengan skor 4,02 (sangat baik), buku siswa dengan skor 3,95 (baik); dan tes KBKM dengan skor 3,78 (baik); (2) pembelajaran matematika dinyatakan efektifkarena KBKM mencapai ketuntasan dan terdapat pengaruh positif karakter rasa ingin tahu dan keterampilan berpikir kreatif matematis terhadap KBKM, terdapat rata-rata KBKM antara kelas eksperimen dengan kelas kontrol; dan terdapat peningkatan nilai KBKM. Kemampuan berpikir kreatif matematis seluruh siswa tuntas, akan tetapi pada indikator keaslian beberapa siswa masih kurang, sehingga dapat dilakukan penelitian lebih lanjut untuk menuntaskannya. Students in understanding the material fractions tend difficulties so that the level of success in this material is low. To provide solutions to these problems, researchers developed a model learning device SSCS tool aided puzzle. The purpose of this study was to analyze the creative thinking and character curiosity of students through effective learning. The results of the development of tool aided learning SSCS tool of the puzzle as follows: (1) The device developed learning valid; Syllabus with an average score of 3.82 (good); RPP with a score of 3.95 (good); LKS with a score of 4.02 (very good); Book student with a score of 3.95 (good); and KBKM test with a score of 3.78 (good); (2) Learning mathematics is declared effective, namely: 1) KBKM achieve mastery; 2) There is a positive influence on the character of curiosity and creative thinking skills mathematical against KBKM; 3) There is an average KBKM between experimental class with a grade control; and 4) There is an increase in the value of KBKM. Mathematical creative thinking abilities of all students complete, but the indicators of the authenticity of some students still lacking, so it can do further research to complete.

This study presents an analytical model for calculating the armature reaction magnetic field of outer rotor permanent magnet brushless DC motor (PMBLDCM) in stator stationary coordinate system (SSCS) and rotor rotation coordinate system (RRCS). Firstly, an expression of armature reaction magnetic field of single‐phase winding is deduced, without considering slotting effect. Afterwards, analytical expressions of armature reaction magnetic field in both SSCS and RRCS regardless of slotting effect are obtained using vector addition method. Then complex relative permeances of outer rotor BLPMDCM in SSCS and RRCS are analysed, respectively. Finally, analytical solutions of the armature reaction magnetic field in both SSCS and RRCS are derived, respectively, by multiplying the slotless armature reaction magnetic field and the complex relative magnetic permeance, the self‐ and mutual inductance are calculated by the armature reaction magnetic field. A 46‐ploes‐51‐slots outer rotor BLPMDCM is set as an example, the accuracy of proposed analytical model is verified by the Finite Element Method. Based on this analytical model, the pattern of slotting effect on armature reaction of both outer rotor and internal stator are analysed, respectively, as well as spatial order characteristics and frequency characteristics of armature reaction for outer rotor PMBLDCM in SSCS and in RRCS. [ABSTRACT FROM AUTHOR]

Given the potential biological functions of spermatogonial stem cells (SSCs) in spermatogenesis and in delivering parental genetic information to the next generation, how these cells respond to environmental toxins and carcinogens should be investigated. We examined the toxic effect of hexavalent chromium (Cr(VI)) on global histone modifications and apoptotic signaling pathways in SSCs. We determined the effect of melatonin, one of the most powerful endogenous free radical scavengers and wide-spectrum antioxidants, in protecting SSCs from Cr(VI)-induced apoptosis and global histone modification by Western blot analysis. In addition, we examined the in vivo effect of melatonin on Cr(VI)-induced histological changes of seminiferous tubules in mouse testes. We also evaluated the fertility of male mice by monitoring litter size following intraperitoneal injection of these chemicals. Our study demonstrated the Cr(VI)-induced global increases in H3K9me3 and H3K27me3 and activated the apoptotic signaling pathway. Pretreatment of SSCs with melatonin alleviated Cr(VI)-induced apoptosis and the global increase of H3K9me3. Exposure to melatonin also attenuated the Cr(VI)-induced increase of the abundance of histone methyltransferase ESET. Furthermore, exogenous administration of melatonin protected mice against Cr(VI)-induced changes in testicular histology and germ cell apoptosis, which helped maintain normal spermatogenesis and male fertility. Our study revealed a potential new therapeutic approach for male reproductive injury caused by Cr(VI). [ABSTRACT FROM AUTHOR]

Background: Spermatogonial stem cells (SSCs) are undifferentiated cells which are highly reproducible and expandable. Several studies have been conducted to reproduce these cells in culture. They used growth factors, hormones and different feeder cells to improve survival and proliferation of SSCs. Objective: This study was conducted to evaluate the effects of follicular stimulating hormone (FSH) on gene expression of fibroblast growth factor (FGF2) and glial cell-derived neurotrophic factor (GDNF) in Sertoli cells. Materials and Methods: Sertoli cells and SSCs were isolated from 3-5 month-old calves. Bovine testicular cells were cultured for 15 days with or without FSH. Identification of these cells was confirmed by immunocytochemistry analysis. Colony formation of SSCs was evaluated using an inverted microscope. The gene expression of FGF2 and GDNF and the gene markers bcl6b, thy-1, and C-kit were evaluated using the quantitative RT-PCR technique. Results: The results indicated that FSH increased colonization of SSCs. the expression of GDNF, FGF2, and markers of undifferentiated spermatogonia was increased following culture in control and FSH groups (p<0.05), this increase was more in FSH group. Conversely, the expression of C-kit was decreased in both groups (p<0.05). Conclusion: The results showed that FSH can increase the self-renewal of SSCs in vitro via upregulation of GDNF and FGF2 expression in Sertoli cells. [ABSTRACT FROM AUTHOR]

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Spermatogonia Stem Cells (SSCs) are the basis of spermatogenesis. In the poultry industry, asthenospermia and azoospermia in roosters seriously reduce economic benefits. In this study, we explored SSCs formation mechanisms in detail. TDRD1 , which is a downstream target gene of TCF7L2 and is modified by histone methylation, was screened through multiomics analysis. Functionally, RT-qPCR, flow cytometry, immunohistochemistry, and indirect immunofluorescence results showed that H3K4me2 regulated TDRD1 to promote SSCs formation both in vivo and in vitro. Furthermore, ChIP-qPCR and dual luciferase assays showed that H3K4me2 was enriched in the −800 to 0 bp region of the TDRD1 promoter and positively regulated TDRD1 transcription to promote SSCs formation. Interestingly, in mechanistic terms, dual luciferase assays showed that TDRD1 transcription levels were significantly decreased after co-transfection with dCas9-LSD1-P1/P2/P3 and OETCF7L2, while TDRD1 transcript levels were not significantly altered after transfecting dCas9-LSD1-P4 and OETCF7L2. These results suggested that H3K4me2 enrichment in P1, P2, and P3 of the TDRD1 promoter promotes TDRD1 transcription by reducing enrichment of TCF7L2. This study explored the specific regulatory mechanisms involving the Wnt signaling pathway, H3K4me2, and TDRD1, enriched the regulatory network regulating the formation of SSCs, and laid a theoretical foundation for the specific application of SSCs. [ABSTRACT FROM AUTHOR]

The complex process of spermatogenesis is regulated by various factors. Studies onspermatogonial stem cells(SCCs)have provided very important tool to improve herd geneticand different field. 0.2 to 0.3 percent of total cells of seminiferous tubules is consist ofspermatogonial stem cells. To investigate and biomanipulation of these cells, proliferationand viability rate of cells should be increasedin vitro, at first. Follicle stimulating hormone(FSH) has been suggested to play a determinant role in the survival of germ cells in additionto increasing spermatogonial proliferation. In this study, thein vitroeffects ofFSHonspermatogonial cell colony formation were investigated. Sertoli and spermatogonial cellswere isolated from 3-5 months old calves. The identity of theSertoli cells and spermatogonialstem cells were confirmed through immunocytochemistry and colony morphology,respectively. Co-cultured Sertoli and spermatogonial cells were treatedwithFSHin differentdose of10, 20 and 40 IU mL-1FSH, before colony assay.Results indicated that,FSHincreasedin vitrocolonization of spermatogonial cells in comparison with control group. In conclusion,usingFSHprovided proper bovine spermatogonial stem cell culture medium forin vitrostudy of these cells.

Objective: To determine the pattern and extent of stainless steel crown (SSC) reuse following try-in and the methods employed for their decontamination among Indian pediatric dentists. Study Design: Questionnaires were delivered personally to 100 pediatric dentists selected randomly across India. Questionnaire was divided into three subsections. The first section assessed demographics to determine the sample population characteristics. The second section dealt with the pattern of SSCs use and reuse following size determination. The third section inquired into general cross infection control procedures including cleaning, sterilization, and training to assess the general level of compliance. Data analysis involved descriptive analysis using SPSS 16.0 software. Results: The majority of respondents (98.92%) routinely reused the crowns after they had been tried in the patient. Only one respondent (1.08%) discarded the crowns after try-in. Autoclave (25%) was the most common method employed for the decontamination of tried-in SSCs among the respondents. Conclusion: The majority of the participating pediatric dentists are reusing SSCs following try-in during crown selection. However, great diversity exists in the methods employed for the decontamination of the same. This demands for more research to provide guidelines into the most effective method of decontamination.

Testicular spermatogonial stem cells (SSCs) are a heterogeneous population of stem cells, and definitive marker for the most primitive subset that undergoes asymmetric cell division remains to be identified. A novel subpopulation of pluripotent, very small embryonic-like stem cells (VSELs) has been reported in both human and mouse testes. Follicle-stimulating hormone (FSH) receptors (FSHRs) are expressed on Sertoli cells in testis and on granulosa cells in ovary, but recently FSHRs are reported on VSELs in ovaries, bone marrow, and cord blood. The present study was aimed to investigate whether FSHRs are also expressed on testicular stem cells (VSELs and SSCs) and their possible modulation by FSH using intact and chemoablated (25 mg/kg busulfan) mice. Chemoablated testis was a better model to study stem cell biology since quiescent stem cells survive along with the Sertoli cells in the tubules. Proliferating cell nuclear antigen-positive, small-sized cells presumed to be VSELs were clearly visualized, and flow cytometry analysis revealed an increase in LIN−/CD45−/SCA-1+ VSELs from 0.045±0.008% to 0.1±0.03% of total cells in chemoablated testis after FSH treatment. Very small embryonic-like stem cells expressing nuclear octamer-binding transcription factor 4 (OCT-4) and SSCs with cytoplasmic OCT-4 were detected. Very small embryonic-like stem cells (Oct-4A, Sca-1, Nanog), SSCs (Oct-4), and proliferation (Pcna) specific transcripts were upregulated on FSH treatment. Stem cells expressed FSHR and were stimulated by FSH, and Fshr3 was the predominant transcript maximally modulated by FSH. Nuclear OCT-4 and SCA-1 (stem cell antigen 1) positive VSELs are the most primitive stem cells in testis, and FSH stimulates them to undergo asymmetric cell division including self-renewal and give rise to SSCs, which in turn proliferate rapidly and undergo clonal expansion and further differentiation. [ABSTRACT FROM AUTHOR]

Proper in vitro culture and proliferation of spermatogonial stem cells (SSCs) are key tools to achieve functional potentials of SSCs. The fresh serum extracted has been successfully used to stimulate growth of spermatogonial stem cells in vitro. However, there is no report on the optimal concentration of serum for in vitro culture of goat SSCs. This study investigated this issue. Material and methods: Retrieved testicular cells were cultured in DMEM in presence of different 0 to 15% serum for 7 days and examined on 3 and 7 day of culture for colony formation, cell viability, immunocytochemistry and quantitative gene expression analyses. Results: The maximum numbers of colonies were observed in presence of 1% serum on days 3 and 7 of culture. Differential viable staining revealed that most cells were non-viable in complete absence of serum (0%). Immunocytochemistry showed that cells positive for pan cytokeratin were observed in colonies developed in presence of 1, 5, 10 and 15% serum but not 0%, suggesting the presence of epithelial cells within the developing colonies. The colonies developed in the presence of 1 and 5% serum had remarkable alkaline phosphatase activity. The maximum expressions of Plzf, Bcl6b and Vasa were observed in colonies developed in presence of 1% serum, with a significant difference to all the other groups. No significant difference was observed for the expression of Vimentin between different treatment groups. Conclusion: The results of this study indicate that for maintenance of SSCs, 1% serum required for maintaining viability while allowing proliferation and maintenance of SSCs like colonies. [ABSTRACT FROM AUTHOR]