JORGE HALLAK

(Fonte: Lattes)
Índice h a partir de 2011
15
Projetos de Pesquisa
Unidades Organizacionais
Instituto Central, Hospital das Clínicas, Faculdade de Medicina - Médico

Resultados de Busca

Agora exibindo 1 - 5 de 5
  • article 3 Citação(ões) na Scopus
    Surgically retrieved spermatozoa for ICSI cycles in non-azoospermic males with high sperm DNA fragmentation in semen
    (2023) ESTEVES, Sandro C.; COIMBRA, Igor; HALLAK, Jorge
    Intracytoplasmic sperm injection (ICSI) using surgically retrieved spermatozoa outside the classic context of azoospermia has been increasingly used to overcome infertility. The primary indications include high levels of sperm DNA damage in ejaculated spermatozoa and severe oligozoospermia or cryptozoospermia, particularly in couples with ICSI failure for no apparent reason. Current evidence suggests that surgically retrieved spermatozoa for ICSI in the above context improves outcomes, mainly concerning pregnancy and miscarriage rates. The reasons are not fully understood but may be related to the lower levels of DNA damage in spermatozoa retrieved from the testis compared with ejaculated counterparts. These findings are consistent with the notion that excessive sperm DNA damage can be a limiting factor responsible for the failure to conceive. Using testicular in preference of low-quality ejaculated spermatozoa bypasses post-testicular sperm DNA damage caused primarily by oxidative stress, thus increasing the likelihood of oocyte fertilization by genomically intact spermatozoa. Despite the overall favorable results, data remain limited, and mainly concern males with confirmed sperm DNA damage in the ejaculate. Additionally, information regarding the health of ICSI offspring resulting from the use of surgically retrieved spermatoa of non-azoospermic males is still lacking. Efforts should be made to improve the male partner's reproductive health for safer ICSI utilization. A comprehensive andrological evaluation aiming to identify and treat the underlying male infertility factor contributing to sperm DNA damage is essential for achieving this goal.
  • article 5 Citação(ões) na Scopus
    Marijuana Is Associated With a Hormonal Imbalance Among Several Habits Related to Male Infertility: A Retrospective Study
    (2022) TEIXEIRA, Thiago A.; IORI, Ivan; ANDRADE, Gustavo; SALDIVA, Paulo H. N.; DREVET, Joel R.; COSTA, Elaine M. F.; HALLAK, Jorge
    Marijuana is one of the most consumed drugs worldwide. There is increasing evidence of an association between marijuana and male infertility. This study intends to assess the repercussion of marijuana smoking and other habits (sedentary lifestyle, alcohol, and tobacco use) in the testicular function of infertile men seeking andrological evaluation. A retrospective study was performed using medical records data of men aged 18-59 years from 2009 to 2017. Complete semen analyses, sperm functional tests, SHBG, and hormonal levels, testosterone-to-estradiol ratio (T/E-2), and testis volume were evaluated. Exclusion criteria included cryptorchidism, infertility caused by genetic or infectious diseases, and cancer. A multiple linear regression analysis was performed to investigate which habit could predict certain parameters using the software SPSS 23.0 (P < 0.05). In a sample of 153 men, semen parameters, testosterone levels, and testis volume were not significantly influenced. Marijuana use had the broader hormonal changes since it influences estradiol (P = 0.000; B = -11.616), prolactin (P = 0.000; B = 3.211), SHBG levels (P = 0.017; B = 7.489), and T/E-2 (P = 0.004; B = 14.030). Sedentary lifestyle (P = 0.028; B = 1.279) and tobacco smoking (P = 0.031; B = -2.401) influenced the prolactin levels. Marijuana is associated with hormonal imbalance in this infertile cohort by lowering estradiol levels and inhibiting aromatase function.
  • article 0 Citação(ões) na Scopus
    Identification of PDCL2 as a candidate marker in Sertoli cell-only syndrome by chromatin immunoprecipitation-sequencing and bioinformatics analysis
    (2023) YANG, Yu; QIN, Si; WU, Hongwei; ZHANG, Jiahao; TIAN, Qiao; ZHAO, Zhengping; WEI, Benlin; HALLAK, Jorge; MAO, Xiangming
    Background: Sertoli cell-only syndrome (SCOS) or germ cell aplasia is one of the most serious histopathological subtypes within the scope of non-obstructive azoospermia (NOA). Understanding the molecular mechanism of SCOS and identifying new non-invasive markers for clinical application is crucial to guide proper sperm procurement and avoid unnecessary interventions. This study sought to identify the differentially expressed genes (DEGs) of SCOS by using gene sequencing identity and verify the key marker genes to provide basic data for subsequent research on SCOS.Methods: A total of 50 testicular samples were collected in this study from 25 patients with SCOS and 25 patients with normal spermatogenesis. In total, 5 pairs of testis samples were used for the RNA-sequencing (RNA-seq). We identified the DEGs between the SCOS and normal spermatogenesis patients and conducted a Gene Ontology (GO) analysis and a Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. The expression of the main target gene phosducin-like 2 (PDCL2) was examined by quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry (IHC).Results: In total, 3,133 upregulated DEGs and 1,406 downregulated DEGs were identified by the RNA-seq. The highly enriched processes involved in spermatogenesis included the mitotic cell cycle, cell cycle, and oocyte maturation. The expression of PDCL2 was verified as a downregulation marker in SCOS by qRT-PCR and IHC. Conclusions: This study identified the DEGs of SCOS, and the bioinformatics analysis results identified the potential target key genes and pathways for SCOS. PDCL2 is a key gene involved in SCOS and may serve as a non-invasive downregulation marker of SCOS.