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1.
Transl Androl Urol ; 10(1): 397-407, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33532327

RESUMO

BACKGROUND: Conventional cryopreservation methods induce chemical and mechanical damage to the sperm membranes. The cryoprotectant potential of phospholipids of vegetal origin as soybean lecithin has been investigated as a substitute for egg yolk in diluents used for the cryopreservation of human spermatozoa. Therefore, the objective of this study was comparing the efficacy of a synthetic cryoprotectant supplemented with L-α-phosphatidylcholine (PC) and L-acetyl-carnitine (ANTIOX-PC) and the standard egg-based TEST-yolk buffer (TYB) in preserving sperm motility and chromatin quality in cryopreserved semen samples. METHODS: Prospective experimental study in which semen samples from 63 men with normal sperm motility and 58 men with low sperm motility were included and analyzed both before and after cryopreservation using ANTIOX-PC or TYB freezing media. Sperm quality was evaluated by routine semen analysis and DNA fragmentation index using the Terminal deoxynucleotidyl transferase dUTP nick end labeling assay. RESULTS: Differences in the post-thaw progressive motility and DNA fragmentation index were not detected between TYB and ANTIOX-PC cryoprotectants in both normal and low sperm motility groups (P>0.05). However, ANTIOX-PC medium retained higher non-progressive motility and lower percentage of immotile sperm when compared to TYB medium, resulting in a greater total motile sperm count (P<0.05), regardless baseline values of motility characteristic of the normospermic or asthenozoospermic samples. CONCLUSIONS: ANTIOX-PC medium was effective to protect human sperm during a freeze-thaw cycle compared to the TYB medium. A clinically relevant advantage in better preserving kinetic parameters as higher total motility and lower immotile post-thawed sperm from ANTIOX-PC, in normal and low motility semen samples, demonstrated the positive impact of phospholipid and antioxidant treatment on sperm cryotolerance with high potential for egg yolk lipids replacement and biosafety.

2.
Syst Biol Reprod Med ; 65(2): 95-104, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30601031

RESUMO

Varicocele pathophysiology is related to increased oxidative stress, which might result in loss sperm DNA integrity as well as in genomic instability. Sperm telomere shortening and loss of global DNA methylation are the main features of genomic instability, leading to cell senescence and death, whereas sperm DNA fragmentation (SDF) characterizes the loss of chromatin integrity. We hypothesize that sperm genomic stability and DNA integrity is reduced in infertile men with moderate and large-sized varicoceles, thus being candidate markers of sperm quality in varicocele-related infertility. Here, we assessed the sperm global DNA methylation, telomere length, and SDF in men with and without clinically palpable varicoceles. While the rates of SDF and telomere length were not statistically different between varicocele patients and controls, global sperm DNA methylation seems to be lower in men with varicocele (49.7% ± 20.7%) than controls (64.7% ± 17.1%). A negative correlation between SDF and sperm motility and a positive correlation between sperm morphology and telomere length were observed. Our results suggest that varicocele may result in genomic instability, in particular, global DNA hypomethylation. However, a large sample size may confirm these findings. The understanding of the molecular mechanisms involved in the pathophysiology of varicocele-related infertility may help to better select candidates for varicocele repair.


Assuntos
Metilação de DNA , Telômero , Varicocele/genética , Adulto , Estudos Transversais , Fragmentação do DNA , Humanos , Infertilidade Masculina/genética , Masculino , Espermatozoides/metabolismo
3.
Int J Health Sci (Qassim) ; 12(2): 37-42, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29599693

RESUMO

OBJECTIVES: The objective of this research was to analyze the functional changes of lower limbs by means of surface electromyography in patients with acquired immunodeficiency syndrome. METHODS: A total of 60 men and women (age mean of 36.77 ± 9.33 years) were divided into two groups: 30 individuals with human immunodeficiency virus group (HIVG) Subtype 1 and 30 healthy individuals control group. Muscle activity was evaluated using surface electromyography (sEMG). sEMG measurements were made while the subjects assumed the static positions: Rest in orthostatism (RS), squat "normalization factor," right and left single leg support (RSLS, LSLS) and during functional activities: Right and left single leg step rise (RSLSR, LSLSR), right and left single leg step down (RSLSD, LSLSD), rising and seating on a chair (RC, SC). RESULTS: To sEMG results revealed statistically significant values in the conditions of RSLS to left semitendinosus muscle, for LSLS to right and left semitendinosus, right rectus femoris and right gluteus medius muscles, for LSLSR to right rectus femoris and right tensor fasciae latae muscles, for RSLSD to right and left semitendinosus and right rectus femoris muscles, for RC to right rectus femoris and left gluteus medius muscles and for SC to right semitendinosus, right rectus femoris and right and left gluteus medius muscles. CONCLUSION: It can be concluded that individuals with acquired immunodeficiency syndrome presented changes in lower limb muscle activity.

4.
J Electromyogr Kinesiol ; 25(3): 515-21, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25783860

RESUMO

PURPOSE: To understand the effects of HIV type 1 on the function of the masticatory muscles. METHODS: Sixty individuals were selected from both genders, aged between 22 and 57years (mean 36.77±9.33years), and divided into two groups: Group HIVG, 30 individuals with HIV subtype 1, and Group CG, 30 healthy individuals (control group). The individuals were submitted to assessments of their masticatory muscle activity, biting strength and thickness of the masticatory muscles by means of electromyography, maximal molar bite force and ultrasound imaging, respectively. The resultant data were statistically analyzed by t-tests (p<0.05). RESULTS: The HIVG normalized EMG data from a mandibular rest position, protrusion, right and left laterality movement of the jaw showed that HIVG presented a relative increase in EMG activity compared to the CG. The HIVG had a lower masticatory cycle ability while chewing Parafilm M®, Raisins and Peanuts when compared to CG. During rest conditions, the ultrasound images showed a greater average muscular thickness in the right and left temporal region compared to CG. Upon maximal voluntary contraction, an increased average thickness was seen in the temporalis muscles and left sternocleidomastoid muscle when compared to the CG. CONCLUSION: Based on the results of this research, it can be concluded that individuals with acquired immunodeficiency syndrome showed muscular changes related to the stomatognathic system, especially concerning EMG activity and muscle thickness.


Assuntos
Eletromiografia/métodos , Infecções por HIV/diagnóstico , Infecções por HIV/fisiopatologia , HIV-1 , Sistema Estomatognático/fisiopatologia , Adulto , Força de Mordida , Feminino , Humanos , Masculino , Músculo Masseter/fisiopatologia , Mastigação/fisiologia , Músculos da Mastigação/fisiopatologia , Pessoa de Meia-Idade , Músculos do Pescoço/fisiologia , Músculo Temporal/fisiopatologia , Adulto Jovem
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