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1.
Dev Biol ; 496: 15-23, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36657507

RESUMO

BACKGROUND: Cornichon is a functionally conserved transmembrane protein family that generally acts as a cargo-sorting receptor and cycles between the ER and the Golgi. Four Cornichon family members (CNIH1-4) have been identified. The key residues responsible for CNIH1-3 to bind to AMPA receptors are not conserved in CNIH4. Additionally, the function of CNIH1-3 in GPCR signaling is less established, while more established in case of CNIH4 protein that interact with GPCR and control their exportation. Many GPCRs are known for their essential roles in male and female gonad development. But whether CNIH4 plays a role in gametogenesis remains unknown. DESIGN: Mice carrying the Cnih4 knockout allele (Cnih4tm1a-/-) were generated by insertion of a LacZ reporter and a polyadenylation site after exon 1. Western blot, Immunofluorescence, computer-aided sperm analysis and other methods were used in the functional analysis. RESULTS: We identified that both Cnih4tm1a-/- male and female mice have normal fertility. Though, the sperm count, morphology, and motility of Cnih4tm1a-/- mice were slightly impaired compared to those of wild-type mice, the testes to body weight ratio and testicular histology were similar to those in control mice. Histological examination of Cnih4tm1a-/- ovaries detected follicles from primordial to antral stages and the numbers of follicles at each stage were also comparable to wild-type controls. Normal fertility was noticed after six-month fertility tests. That was likely due to the compensatory role of Chin3, which significantly upregulated in the Cnih4tm1a-/- mice to preserve the fertility role. CONCLUSION: Despite CNIH4 showing enriched expression in mouse germ cells, our genetic knockout studies demonstrated that CNIH4 is not essential for gametogenesis and fertility in mice although with a slight reduction in count, motility and morphology of sperm in male mice.


Assuntos
Fertilidade , Sêmen , Masculino , Feminino , Animais , Camundongos , Fertilidade/genética , Testículo/metabolismo , Espermatozoides/metabolismo , Gametogênese , Espermatogênese/genética , Camundongos Knockout
2.
Am J Hum Genet ; 108(2): 324-336, 2021 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-33508233

RESUMO

Human infertility is a multifactorial disease that affects 8%-12% of reproductive-aged couples worldwide. However, the genetic causes of human infertility are still poorly understood. Synaptonemal complex (SC) is a conserved tripartite structure that holds homologous chromosomes together and plays an indispensable role in the meiotic progression. Here, we identified three homozygous mutations in the SC coding gene C14orf39/SIX6OS1 in infertile individuals from different ethnic populations by whole-exome sequencing (WES). These mutations include a frameshift mutation (c.204_205del [p.His68Glnfs∗2]) from a consanguineous Pakistani family with two males suffering from non-obstructive azoospermia (NOA) and one female diagnosed with premature ovarian insufficiency (POI) as well as a nonsense mutation (c.958G>T [p.Glu320∗]) and a splicing mutation (c.1180-3C>G) in two unrelated Chinese men (individual P3907 and individual P6032, respectively) with meiotic arrest. Mutations in C14orf39 resulted in truncated proteins that retained SYCE1 binding but exhibited impaired polycomplex formation between C14ORF39 and SYCE1. Further cytological analyses of meiosis in germ cells revealed that the affected familial males with the C14orf39 frameshift mutation displayed complete asynapsis between homologous chromosomes, while the affected Chinese men carrying the nonsense or splicing mutation showed incomplete synapsis. The phenotypes of NOA and POI in affected individuals were well recapitulated by Six6os1 mutant mice carrying an analogous mutation. Collectively, our findings in humans and mice highlight the conserved role of C14ORF39/SIX6OS1 in SC assembly and indicate that the homozygous mutations in C14orf39/SIX6OS1 described here are responsible for infertility of these affected individuals, thus expanding our understanding of the genetic basis of human infertility.


Assuntos
Azoospermia/genética , Mutação , Insuficiência Ovariana Primária/genética , Adulto , Azoospermia/fisiopatologia , Pareamento Cromossômico , Códon sem Sentido , Proteínas de Ligação a DNA/metabolismo , Feminino , Homozigoto , Humanos , Masculino , Meiose , Pessoa de Meia-Idade , Proteínas Nucleares/metabolismo , Linhagem , Insuficiência Ovariana Primária/fisiopatologia , Espermatócitos/metabolismo , Espermatócitos/fisiologia , Complexo Sinaptonêmico/genética , Complexo Sinaptonêmico/metabolismo , Sequenciamento Completo do Genoma
3.
HIV Med ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858222

RESUMO

INTRODUCTION: Long-acting injectable cabotegravir + rilpivirine (CAB + RPV LAI) was approved for use in virally suppressed adults in the England and Wales national health service in November 2021. We describe a service evaluation of delivery processes and outcomes in 12 clinics. METHODS: Centres populated a database using information from local policies and clinical records. Services were asked to describe approval processes, clinic pathways, and adherence to national guidelines. Additional data were collected on reasons for regimen choice, treatment discontinuations, and management of viraemia. RESULTS: In total, 518 adults from 12 clinics were approved for CAB + RPV LAI between February 2022 and December 2023. Of the 518 people approved for CAB + RPV LAI, 423 received at least one injection. Median duration on CAB + RPV was 7.5 months (interquartile range 3.7-11.3). In total, 97% of injections were administered within the ±7-day window. Virological failure occurred in 0.7%, and 6% discontinued CAB + RPV. CONCLUSION: In this large UK-based cohort, robust approval processes and clinic protocols facilitated on-time injections and low rates of both discontinuation and virological failure.

4.
Ophthalmology ; 131(5): 568-576, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38092080

RESUMO

PURPOSE: To benchmark the epidemiologic features of pediatric ocular surface inflammatory diseases (POSID). DESIGN: Retrospective cohort study. PARTICIPANTS: Patients 18 years of age or younger with a medical claim for a diagnosis of POSID in the Optum Labs Data Warehouse between 2007 and 2020. METHODS: Patients with claims of blepharokeratoconjunctivitis (BKC), herpes simplex keratoconjunctivitis (HSK), or vernal keratoconjunctivitis (VKC) were included. Those with less than 6 months of follow-up before the initial diagnosis of POSID were excluded. Odds ratios (ORs) were derived from multivariable logistic regression analyses evaluating the associations between epidemiologic variables and POSID development. MAIN OUTCOME MEASURES: The primary outcome was the estimated prevalence of POSID. Prevalence of POSID subtypes and changes in prevalence over time were also evaluated. RESULTS: Two thousand one hundred sixty-eight patients with POSID were identified from 2018 through 2019, yielding an estimated prevalence of 3.32 per 10 000. The prevalence of POSID was higher among children between 5 and 10 years of age, male children, those of Asian descent, and those living in the Northeast and the West census regions of the United States. The prevalence (per 10 000) of BKC, HSK, and VKC in the same period were 0.59 (95% confidence interval [CI], 0.53-0.65), 0.74 (95% CI, 0.68-0.81), and 1.99 (95% CI, 1.88-2.10), respectively, and significant differences were found in terms of age, sex, racial, ethnic, and regional distributions among the diagnoses. Between 2008 through 2009 and 2018 through 2019, a significant increase in POSID was noted among Asians (from 6.26 [95% CI, 5.28-7.36] to 11.80 [95% CI, 10.40-13.34]) driven by changes in VKC. Multivariable analysis demonstrated that age older than 5 years (OR, 2.57-3.75; 95% CI, 2.17-4.34), male sex (OR, 1.38; 95% CI, 1.26-1.50), Asian descent (OR, 3.12; 95% CI, 2.70-3.60), and Black or African American descent (OR, 1.26; 95% CI, 1.02-1.55) were associated with POSID development. CONCLUSIONS: This study provides an estimated prevalence of POSID and its 3 common subtypes in the United States, with important epidemiologic differences among them. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

5.
J Assist Reprod Genet ; 41(1): 109-120, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37831349

RESUMO

PURPOSE: Asthenozoospermia is an important cause of male infertility, and the most serious type is characterized by multiple morphological abnormalities of the sperm flagella (MMAF). However, the precise etiology of MMAF remains unknown. In the current study, we recruited a consanguineous Pakistani family with two infertile brothers suffering from primary infertility due to MMAF without obvious signs of PCD. METHODS: We performed whole-exome sequencing on DNAs of the patients, their parents, and a fertile brother and identified the homozygous missense variant (c.1490C > G (p.P497R) in NPHP4 as the candidate mutation for male infertility in this family. RESULTS: Sanger sequencing confirmed that this mutation recessively co-segregated with the MMAF in this family. In silico analysis revealed that the mutation site is conserved across different species, and the identified mutation also causes abnormalities in the structure and hydrophobic interactions of the NPHP4 protein. Different bioinformatics tools predict that NPHP4p.P497R mutation is pathogenic. Furthermore, Papanicolaou staining and scanning electron microscopy of sperm revealed that affected individuals displayed typical MMAF phenotype with a high percentage of coiled, bent, short, absent, and/or irregular flagella. Transmission electron microscopy images of the patient's spermatozoa revealed significant anomalies in the sperm flagella with the absence of a central pair of microtubules (9 + 0) in every section scored. CONCLUSIONS: Taken together, these results show that the homozygous missense mutation in NPHP4 is associated with MMAF.


Assuntos
Infertilidade Masculina , Irmãos , Humanos , Masculino , Flagelos/genética , Infertilidade Masculina/genética , Infertilidade Masculina/patologia , Mutação , Mutação de Sentido Incorreto/genética , Proteínas/genética , Sêmen , Cauda do Espermatozoide/patologia , Espermatozoides/patologia
6.
Facial Plast Surg ; 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38378042

RESUMO

Deficits in corneal innervation lead to neurotrophic keratopathy (NK). NK is frequently associated with facial palsy, and corneal damage can be accelerated by facial palsy deficits. Corneal nerves are important regulators of limbal stem cells, which play a critical role in epithelial maintenance and healing. Nonsurgical treatments of NK have undergone recent innovation, and growth factors implicated in corneal epithelial renewal are a promising therapeutic avenue. However, surgical intervention with corneal neurotization (CN) remains the only definitive treatment of NK. CN involves the transfer of unaffected sensory donor nerve branches to the affected cornea, and a variety of donor nerves and approaches have been described. CN can be performed in a direct or indirect manner; employ the supraorbital, supratrochlear, infraorbital, or great auricular nerves; and utilize autograft, allograft, or nerve transfer alone. Unfortunately, comparative studies of these factors are limited due to the procedure's novelty and varied recovery timelines after CN. Regardless of the chosen approach, CN has been shown to be a safe and effective procedure to restore corneal sensation and improve visual acuity in patients with NK.

7.
Int J Mol Sci ; 24(16)2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37628793

RESUMO

The cornea is the window through which we see the world. Corneal clarity is required for vision, and blindness occurs when the cornea becomes opaque. The cornea is covered by unique transparent epithelial cells that serve as an outermost cellular barrier bordering between the cornea and the external environment. Corneal sensory nerves protect the cornea from injury by triggering tearing and blink reflexes, and are also thought to regulate corneal epithelial renewal via unknown mechanism(s). When protective corneal sensory innervation is absent due to infection, trauma, intracranial tumors, surgery, or congenital causes, permanent blindness results from repetitive epithelial microtraumas and failure to heal. The condition is termed neurotrophic keratopathy (NK), with an incidence of 5:10,000 people worldwide. In this report, we review the currently available therapeutic solutions for NK and discuss the progress in our understanding of how the sensory nerves induce corneal epithelial renewal.


Assuntos
Distrofias Hereditárias da Córnea , Fenômenos Fisiológicos do Sistema Nervoso , Humanos , Córnea , Cegueira , Vias Aferentes
8.
Am J Hum Genet ; 104(3): 422-438, 2019 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-30773277

RESUMO

SPONASTRIME dysplasia is an autosomal-recessive spondyloepimetaphyseal dysplasia characterized by spine (spondylar) abnormalities, midface hypoplasia with a depressed nasal bridge, metaphyseal striations, and disproportionate short stature. Scoliosis, coxa vara, childhood cataracts, short dental roots, and hypogammaglobulinemia have also been reported in this disorder. Although an autosomal-recessive inheritance pattern has been hypothesized, pathogenic variants in a specific gene have not been discovered in individuals with SPONASTRIME dysplasia. Here, we identified bi-allelic variants in TONSL, which encodes the Tonsoku-like DNA repair protein, in nine subjects (from eight families) with SPONASTRIME dysplasia, and four subjects (from three families) with short stature of varied severity and spondylometaphyseal dysplasia with or without immunologic and hematologic abnormalities, but no definitive metaphyseal striations at diagnosis. The finding of early embryonic lethality in a Tonsl-/- murine model and the discovery of reduced length, spinal abnormalities, reduced numbers of neutrophils, and early lethality in a tonsl-/- zebrafish model both support the hypomorphic nature of the identified TONSL variants. Moreover, functional studies revealed increased amounts of spontaneous replication fork stalling and chromosomal aberrations, as well as fewer camptothecin (CPT)-induced RAD51 foci in subject-derived cell lines. Importantly, these cellular defects were rescued upon re-expression of wild-type (WT) TONSL; this rescue is consistent with the hypothesis that hypomorphic TONSL variants are pathogenic. Overall, our studies in humans, mice, zebrafish, and subject-derived cell lines confirm that pathogenic variants in TONSL impair DNA replication and homologous recombination-dependent repair processes, and they lead to a spectrum of skeletal dysplasia phenotypes with numerous extra-skeletal manifestations.


Assuntos
Instabilidade Cromossômica , Dano ao DNA , Variação Genética , Anormalidades Musculoesqueléticas/patologia , NF-kappa B/genética , Osteocondrodisplasias/patologia , Adolescente , Adulto , Alelos , Animais , Células Cultivadas , Criança , Pré-Escolar , Feminino , Fibroblastos/metabolismo , Fibroblastos/patologia , Estudos de Associação Genética , Humanos , Camundongos , Camundongos Knockout , Anormalidades Musculoesqueléticas/genética , Osteocondrodisplasias/genética , Sequenciamento do Exoma , Adulto Jovem , Peixe-Zebra
9.
Graefes Arch Clin Exp Ophthalmol ; 260(9): 2877-2885, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35895106

RESUMO

PURPOSE: To assess the accuracy of the Kane formula for intraocular lens (IOL) power calculation in the pediatric population. METHODS: The charts of pediatric patients who underwent cataract surgery with in-the-bag IOL implantation with one of two IOL models (SA60AT or MA60AC) between 2012 and 2018 in The Hospital for Sick Children, Toronto, Ontario, CanFada, were retrospectively reviewed. The accuracy of IOL power calculation with the Kane formula was evaluated in comparison with the Barrett Universal II (BUII), Haigis, Hoffer Q, Holladay 1, and Sanders-Retzlaff-Kraff Theoretical (SRK/T) formulas. RESULTS: Sixty-two eyes of 62 patients aged 6.2 (IQR 3.2-9.2) years were included. The SD values of the prediction error obtained by Kane (1.38) were comparable with those by BUII (1.34), Hoffer Q (1.37), SRK/T (1.40), Holaday 1 (1.41), and Haigis (1.50), all p > 0.05. A significant difference was observed between the Hoffer Q and Haigis formulas (p = 0.039). No differences in the median and mean absolute errors were found between the Kane formula (0.54 D and 0.91 ± 1.04 D) and BUII (0.50 D and 0.88 ± 1.00 D), Hoffer Q (0.48 D and 0.88 ± 1.05 D), SRK/T (0.72 D and 0.97 ± 1.00 D), Holladay 1 (0.63 D and 0.94 ± 1.05 D), and Haigis (0.57 D and 0.98 ± 1.13 D), p = 0.099. CONCLUSION: This is the first study to investigate the Kane formula in pediatric cataract surgery. Our results place the Kane among the noteworthy IOL power calculation formulas in this age group, offering an additional means for improving IOL calculation in pediatric cataract surgery. The heteroscedastic statistical method was first implemented to evaluate formulas' predictability in children.


Assuntos
Catarata , Lentes Intraoculares , Facoemulsificação , Biometria , Criança , Humanos , Óptica e Fotônica , Refração Ocular , Estudos Retrospectivos
10.
Water Sci Technol ; 86(6): 1308-1324, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36178808

RESUMO

The Denitrification-Decomposition (DNDC)-Rice is a mechanistic model which is widely used for the simulation and estimation of greenhouse gas emissions [nitrous oxide (N2O)] from soils under rice cultivation. N2O emissions from paddy fields in South Korea are of high importance for their cumulative effect on climate. The objective of this study was to estimate the N2O emissions and biogeochemical factors involved in N2O emissions such as ammonium (NH4+) and nitrate (NO3-) using the DNDC model in the rice-growing regions of South Korea. N2O emission was observed at every application of fertilizer and during end-season drainage at different rice-growing regions in South Korea. Maximum NH4+ and NO3- were observed at 0-10 cm depth of soil. NH4+ increased at each fertilizer application and no change in NO3- was observed during flooding. NH4+ decreased and NO3- increased simultaneously at end-season drainage. Minimum and maximum cumulative N2O emissions were observed at Chungcheongbuk-do and Jeju-do regions of South Korea, respectively. The simulated average cumulative N2O emission in rice paddies of South Korea was 1.37 kg N2O-N ha-1 season-1. This study will help in calculating the total nitrogen emissions from agriculture land of South Korea and the World.


Assuntos
Compostos de Amônio , Gases de Efeito Estufa , Oryza , Agricultura , China , Fertilizantes/análise , Nitratos , Nitrogênio/análise , Óxido Nitroso/análise , Solo/química
11.
Clin Genet ; 99(1): 176-186, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33070343

RESUMO

Multiple morphological abnormalities of the flagella (MMAF) is a genetically heterogeneous disorder leading to male infertility. Recent studies have revealed that DNAH17 variants are associated with MMAF, yet there is no functional evidence in support of their pathnogenicity. Here, we recruited two consanguineous families of Pakistani and Chinese origins, respectively, diagnosed with MMAF. Whole-exome sequencing identified novel homozygous DNAH17 variants, which led to loss of DNAH17 proteins, in the patients. Transmission electron microscope analyses revealed completely disorganized axonemal structure as the predominant anomaly and increased frequencies of missings of microtubule doublet(s) 4-7 in sperm flagella of patients. Similar to those found in patients, Dnah17-/- mice also displayed MMAF phenotype along with completely disorganized axonemal structures. Clusters of disorganized microtubules and outer dense fibers were observed in developing spermatids, indicating impaired sperm flagellar assembly. Besides, we also noticed many elongating spermatids with a deformed nuclear shape and abnormal step 16 spermatids that failed to spermiate, which subsequently underwent apoptosis in Dnah17-null mice. These findings present direct evidence establishing that DNAH17 is a MMAF-related gene in humans and mice, extend the clinical interpretations of DNAH17 variants, and highlight an essential and complex role of DNAH17 in spermatogenesis.


Assuntos
Anormalidades Múltiplas/genética , Dineínas do Axonema/genética , Infertilidade Masculina/genética , Espermatogênese/genética , Anormalidades Múltiplas/metabolismo , Anormalidades Múltiplas/patologia , Alelos , Animais , Astenozoospermia/genética , Astenozoospermia/patologia , Dineínas do Axonema/metabolismo , Axonema/genética , Axonema/patologia , Flagelos/genética , Flagelos/patologia , Homozigoto , Humanos , Infertilidade Masculina/patologia , Mutação com Perda de Função/genética , Masculino , Camundongos , Cauda do Espermatozoide/metabolismo , Cauda do Espermatozoide/patologia , Espermatozoides/metabolismo , Espermatozoides/patologia , Testículo/crescimento & desenvolvimento , Testículo/patologia , Sequenciamento do Exoma
12.
PLoS Genet ; 14(5): e1007300, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29795555

RESUMO

Three waves of H2AX phosphorylation (γH2AX) have been observed in male meiotic prophase I: the first is ATM-dependent and occurs at leptonema, while the second and third are ATR-dependent, occuring at zygonema and pachynema, respectively. The third wave of H2AX phosphorylation marks and silences unsynapsed chromosomes. Little is known about H2AX phosphorylation expands to chromatin-wide regions in spermatocytes. Here, we report that histone acetyltransferase (HAT) MOF is involved in all three waves of H2AX phosphorylation expansion. Germ cell-specific deletion of Mof in spermatocytes by Stra8-Cre (Mof cKO) caused global loss of H4K16ac. In leptotene and zygotene spermatocytes of cKO mice, the γH2AX signals were observed only along the chromosomal axes, and chromatin-wide H2AX phosphorylation was lost. In almost 40% of early-mid pachytene spermatocytes from Mof cKO mice, γH2AX and MDC1 were detected along the unsynapsed axes of the sex chromosomes, but failed to expand, which consequently caused meiotic sex chromosome inactivation (MSCI) failure. Furthermore, though RAD51 was proficiently recruited to double-strand break (DSB) sites, defects in DSB repair and crossover formation were observed in Mof cKO spermatocytes, indicating that MOF facilitates meiotic DSB repair after RAD51 recruitment. We propose that MOF regulates male meiosis and is involved in the expansion of all three waves of H2AX phosphorylation from the leptotene to pachytene stages, initiated by ATM and ATR, respectively.


Assuntos
Histona Acetiltransferases/metabolismo , Histonas/metabolismo , Espermatogênese/fisiologia , Animais , Quebras de DNA de Cadeia Dupla , Reparo do DNA , Feminino , Histona Acetiltransferases/genética , Masculino , Meiose , Camundongos Knockout , Camundongos Transgênicos , Estágio Paquíteno , Fosforilação , Rad51 Recombinase/genética , Rad51 Recombinase/metabolismo , Espermatócitos/citologia , Testículo/fisiologia
14.
Development ; 144(12): 2165-2174, 2017 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-28506985

RESUMO

Proper oocyte development is crucial for female fertility and requires timely and accurate control of gene expression. K (lysine) acetyltransferase 8 (KAT8), an important component of the X chromosome dosage compensation system in Drosophila, regulates gene activity by acetylating histone H4 preferentially at lysine 16. To explore the function of KAT8 during mouse oocyte development, we crossed Kat8flox/flox mice with Gdf9-Cre mice to specifically delete Kat8 in oocytes. Oocyte Kat8 deletion resulted in female infertility, with follicle development failure in the secondary and preantral follicle stages. RNA-seq analysis revealed that Kat8 deficiency in oocytes results in significant downregulation of antioxidant genes, with a consequent increase in reactive oxygen species. Intraperitoneal injection of the antioxidant N-acetylcysteine rescued defective follicle and oocyte development resulting from Kat8 deficiency. Chromatin immunoprecipitation assays indicated that KAT8 regulates antioxidant gene expression by direct binding to promoter regions. Taken together, our findings demonstrate that KAT8 is essential for female fertility by regulating antioxidant gene expression and identify KAT8 as the first histone acetyltransferase with an essential function in oogenesis.


Assuntos
Histona Acetiltransferases/metabolismo , Oogênese/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Antioxidantes/metabolismo , Apoptose , Feminino , Fertilidade/genética , Fertilidade/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Células da Granulosa/metabolismo , Heterocromatina/genética , Heterocromatina/metabolismo , Histona Acetiltransferases/deficiência , Histona Acetiltransferases/genética , Infertilidade Feminina/genética , Infertilidade Feminina/metabolismo , Infertilidade Feminina/patologia , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Oócitos/citologia , Oócitos/metabolismo , Oogênese/genética , Folículo Ovariano/citologia , Folículo Ovariano/metabolismo , Gravidez
15.
FASEB J ; 33(8): 9075-9086, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31084574

RESUMO

As the major somatic cell type, Sertoli cells undergo active proliferation and play essential roles to establish testis cord at fetal stage. They also function to maintain germ cell development throughout the life of testicular development. However, the significance of Sertoli cell number for testis cord development and gonocyte fate is still unclear. Nuclear protein ataxia-telangiectasia (NPAT, also known as p220), a substrate of cyclin E/cyclin-dependent kinase 2, is well known as a regulator of cell proliferation through regulating histone expression. To study the role of NPAT during Sertoli cell development, we generated a mouse strain carrying conditional floxed Npat alleles, when crossing with anti-Müllerian hormone-cre, leading to the specific deletion of Npat in Sertoli cells. Npat disruption in Sertoli cells inhibited the programmed proliferation of fetal Sertoli cells resulting in disruption of developing testis cords, and subsequent postnatal mutant testes were severely hypoplastic. Germ cells, which are presumed to be in quiescent status during perinatal stage, exited G0 phase arrest and re-enter mitotic cell cycle prematurely. Of particular note, some germ cells possessed the meiotic signal in Npat-deficient testes. Our data thus indicates that the function of Npat-dependent Sertoli cells is essential at multiple steps in testis development, and this study also identifies Sertoli cells as a major regulator of germ cell development, which are required to maintain a local growth niche to repress premature mitosis and meiosis of gonocytes.-Jiang, X., Yin, S., Fan, S., Bao, J., Jiao, Y., Ali, A., Iqbal, F., Xu, J., Zhang, Y., Shi, Q. Npat-dependent programmed Sertoli cell proliferation is indispensable for testis cord development and germ cell mitotic arrest.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Proteínas Nucleares/metabolismo , Células de Sertoli/citologia , Células de Sertoli/metabolismo , Testículo/embriologia , Testículo/metabolismo , Animais , Apoptose/genética , Apoptose/fisiologia , Pontos de Checagem do Ciclo Celular/genética , Pontos de Checagem do Ciclo Celular/fisiologia , Proteínas de Ciclo Celular/deficiência , Proteínas de Ciclo Celular/genética , Proliferação de Células/genética , Proliferação de Células/fisiologia , Feminino , Masculino , Meiose/genética , Meiose/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitose/genética , Mitose/fisiologia , Proteínas Nucleares/deficiência , Proteínas Nucleares/genética , Gravidez , Túbulos Seminíferos/anormalidades , Túbulos Seminíferos/embriologia , Túbulos Seminíferos/metabolismo , Espermatogênese/genética , Espermatogênese/fisiologia , Espermatozoides/citologia , Espermatozoides/metabolismo , Testículo/citologia
16.
BMC Med Educ ; 20(1): 438, 2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-33198727

RESUMO

BACKGROUND: Educational capacity building in pediatric ophthalmology is necessary to address the burden of childhood blindness in Ethiopia. Residency and fellowship training at Addis Ababa University (AAU) have been enhanced with support from the University of Toronto (UofT), following the established Toronto Addis Ababa Academic Collaboration (TAAAC). Our aim was to assess the feasibility of implementing a pediatric ophthalmology fellowship at AAU with support from UofT, modeled by successful postgraduate medical education within TAAAC. METHODS: A situational analysis, including a needs assessment, was conducted at Menelik II Hospital, Addis Ababa. Staff expertise, equipment and infrastructure were compared to International Council of Ophthalmology fellowship guidelines. Patient volumes were assessed through medical chart review. Local training needs were evaluated. A strategic working meeting facilitated program specification. RESULTS: The faculty consisted of 11 ophthalmologists, including 2 pediatric specialists. Fourteen thousand six hundred twenty-seven medical and three thousand six hundred forty-one surgical pediatric cases were seen in the previous year. A 2-year fellowship incorporating anterior segment, retinoblastoma, strabismus, and retinopathy of prematurity modules was developed. Research collaborations, didactic teaching, and surgical supervision were identified as priorities requiring support. Quality standard indicators included faculty feedback, case log review and formal examination. Telemedicine, development of a larger eye hospital and partnerships to support equipment maintenance were identified as strategies to manage implementation barriers. CONCLUSIONS: The situational analysis provided a way forward for the development of a pediatric ophthalmology fellowship, the first of its kind in Eastern Africa. Learning outcomes are feasible given high patient volumes, qualified staff supervision and sufficient equipment. Strategic partnerships may ensure resource sustainability.


Assuntos
Educação Médica , Oftalmologia , Canadá , Criança , Etiópia , Bolsas de Estudo , Humanos , Recém-Nascido , Oftalmologia/educação
17.
Int J Mol Sci ; 21(18)2020 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-32971934

RESUMO

The persistent nature of lead (Pb) and cadmium (Cd) in the environment severely affects plant growth and yield. Conversely, plants acquire zinc (Zn) from the soil for their vital physiological and biochemical functions. However, the interplay and coordination between essential and toxic metals for their uptake and translocation and the putative underlying epigenetic mechanisms have not yet been investigated in maize. Here, we report that the presence of Zn facilitates the accumulation and transport of Pb and Cd in the aerial parts of the maize plants. Moreover, the Zn, Pb, and Cd interplay specifically interferes with the uptake and translocation of other divalent metals, such as calcium and magnesium. Zn, Pb, and Cd, individually and in combinations, differentially regulate the expression of DNA methyltransferases, thus alter the DNA methylation levels at the promoter of Zinc-regulated transporters, Iron-regulated transporter-like Protein (ZIP) genes to regulate their expression. Furthermore, the expression of histone deacetylases (HDACs) varies greatly in response to individual and combined metals, and HDACs expression showed a negative correlation with ZIP transporters. Our study highlights the implication of DNA methylation and histone acetylation in regulating the metal stress tolerance dynamics through Zn transporters and warns against the excessive use of Zn fertilizers in metal contaminated soils.


Assuntos
Metilação de DNA , DNA de Plantas/metabolismo , Histonas/metabolismo , Metais/metabolismo , Proteínas de Plantas/metabolismo , Zea mays/metabolismo , Transporte Biológico , Histona Desacetilases/metabolismo , Raízes de Plantas/metabolismo
18.
Biol Blood Marrow Transplant ; 25(2): e46-e54, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30481594

RESUMO

Ocular graft-versus-host disease (GVHD) occurs in more than one-half of patients who develop chronic GVHD after allogeneic hematopoietic cell transplantation (HCT), causing prolonged morbidity that affects activities of daily living and quality of life. Here we provide an expert review of ocular GVHD in a collaboration between transplantation physicians and ophthalmologists through the Late Effects and Quality of Life Working Committee of the Center for International Blood and Marrow Transplant Research and the Transplant Complications Working Party of the European Society of Blood and Marrow Transplantation. Recent updates in ocular GVHD regarding pathophysiology, preclinical models, risk factors, prevention, screening, diagnosis, response criteria, evaluation measures, and treatment are discussed. Ocular GVHD involves at least 3 biological processes: lacrimal gland dysfunction, meibomian gland dysfunction, and corneoconjunctival inflammation. Preclinical models have identified several novel pathogenic mechanisms, including the renin angiotensin system and endoplasmic reticulum stress signaling, which can be targeted by therapeutic agents. Numerous studies have identified reliable tests for establishing diagnosis and response assessment of ocular GVHD. The efficacy of systemic and topical treatment for ocular GVHD is summarized. It is important that all health professionals caring for HCT recipients have adequate knowledge of ocular GVHD to provide optimal care.


Assuntos
Oftalmopatias , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Transplante de Medula Óssea , Europa (Continente) , Oftalmopatias/metabolismo , Oftalmopatias/patologia , Oftalmopatias/fisiopatologia , Oftalmopatias/prevenção & controle , Doença Enxerto-Hospedeiro/metabolismo , Doença Enxerto-Hospedeiro/patologia , Doença Enxerto-Hospedeiro/fisiopatologia , Doença Enxerto-Hospedeiro/prevenção & controle , Humanos , Fatores de Risco , Sociedades Médicas , Transplante Homólogo
19.
Biol Blood Marrow Transplant ; 25(5): e145-e154, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30521975

RESUMO

Non-graft-versus-host disease (GVHD) ocular complications are generally uncommon after hematopoietic cell transplantation (HCT) but can cause prolonged morbidity affecting activities of daily living and quality of life. Here we provide an expert review of non-GVHD ocular complications in a collaboration between transplantation physicians and ophthalmologists through the Late Effects and Quality of Life Working Committee of the Center for International Blood and Marrow Transplant Research and the Transplant Complications Working Party of the European Society of Blood and Marrow Transplantation. Complications discussed in this review include cataracts, glaucoma, ocular infections, ocular involvement with malignancy, ischemic microvascular retinopathy, central retinal vein occlusion, retinal hemorrhage, retinal detachment and ocular toxicities associated with medications. We summarize the incidence, risk factors, screening, prevention, and treatment of individual complications and generate evidence-based recommendations. Baseline ocular evaluation before HCT should be considered in all patients who undergo HCT. Follow-up evaluations should be considered according to clinical signs and symptoms and risk factors. Better preventive strategies and treatments remain to be investigated for individual ocular complications after HCT. Both transplantation physicians and ophthalmologists should be knowledgeable about non-GVHD ocular complications and provide comprehensive collaborative team care.


Assuntos
Oftalmopatias/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Oftalmopatias/diagnóstico , Oftalmopatias/prevenção & controle , Oftalmopatias/terapia , Humanos , Incidência , Programas de Rastreamento , Equipe de Assistência ao Paciente , Fatores de Risco
20.
Genet Med ; 21(1): 62-70, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29895858

RESUMO

PURPOSE: Fanconi anemia (FA) genes play important roles in spermatogenesis. In mice, disruption of Fancm impairs male fertility and testicular integrity, but whether FANCM pathogenic variants (PV) similarly affect fertility in men is unknown. Here we characterize a Pakistani family having three infertile brothers, two manifesting oligoasthenospermia and one exhibiting azoospermia, born to first-cousin parents. A homozygous PV in FANCM (c.1946_1958del, p.P648Lfs*16) was found cosegregating with male infertility. Our objective is to validate that FANCM p.P648Lfs*16 is the PV causing infertility in this family. METHODS: Exome and Sanger sequencing were used for PV screening. DNA interstrand crosslink (ICL) sensitivity was assessed in lymphocytes from patients. A mouse model carrying a PV nearly equivalent to that in the patients (FancmΔC/ΔC) was generated, followed by functional analysis in spermatogenesis. RESULTS: The loss-of-function FANCM PV increased ICL sensitivity in lymphocytes of patients and FancmΔC/ΔC spermatogonia. Adult FancmΔC/ΔC mice showed spermatogenic failure, with germ cell loss in 50.2% of testicular tubules and round-spermatid maturation arrest in 43.5% of tubules. In addition, neither bone marrow failure nor cancer/tumor was detected in all the patients or adult FancmΔC/ΔC mice. CONCLUSION: These findings revealed male infertility to be a novel phenotype of human patients with a biallelic FANCM PV.


Assuntos
DNA Helicases/genética , Predisposição Genética para Doença , Infertilidade Masculina/genética , Espermatogênese/genética , Adulto , Animais , Mutação da Fase de Leitura , Homozigoto , Humanos , Infertilidade Masculina/patologia , Mutação com Perda de Função/genética , Masculino , Camundongos , Oligospermia/genética , Oligospermia/patologia , Linhagem , Fenótipo , Testículo/patologia
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