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91.
Vicari E 《Human reproduction (Oxford, England)》2000,15(12):2536-2544
To evaluate whether bacteriological cure, sperm outcome, spontaneous pregnancy rate and white blood cell (WBC)-related reactive oxygen species (ROS) production were related to the extent of the infection and to an intermittent and repetitive antimicrobial treatment, 122 patients with bacterial [>10(5) colony-forming units (CFU)/ml] male accessory gland infections (MAGI) were studied. According to ultrasound criteria, patients had prostatitis (PR, n = 52), prostatovesiculitis (PV, n = 32) or prostatovesiculoepididymitis (PVE, n = 38). Each group was further subdivided into two subsets: one subset (PR, n = 40; PV, n = 20; PVE, n = 25) was given ofloxacin or doxycycline for 14 consecutive days per month for 3 months; the other subset (PR, n = 12; PV, n = 12; PVE, n = 13) received no treatment. The female partners were also treated. All patients were evaluated before, during (1 and 3 months) and after (3 months) treatment. The bacteriological cure rate was the highest (92.5%) after the third antibiotic course in PR, followed by PV (70.4%), and the lowest in PVE (52.0%). At 3 months after therapy discontinuation, some sperm parameters, seminal WBC concentration and ROS generation (assessed in the 45% Percoll fraction) were ameliorated in PR and PV, whereas no improvement occurred in patients with PVE, except for the percentage of coiled tails. Antibiotic treatment in PR and PV patients led to positive effects on sperm output and spontaneous pregnancy rate (40%) by removing pro-oxidant noxae (microbial and/or WBC-related ROS production). The persistent infertility, dyspermia and sperm-derived ROS overproduction in PVE may relate to a significant percentage of antibiotic-independent re-infection and/or to low antioxidative epididymal properties, which persisted following antimicrobial treatment. 相似文献
92.
The response of heat shock proteins 25 and 72 to ischaemia in different kidney zones 总被引:1,自引:0,他引:1
A. Schober E. Müller K. Thurau F. X. Beck 《Pflügers Archiv : European journal of physiology》1997,434(3):292-299
Induction of heat shock proteins (HSPs) following cell injury contributes to the protection of vital cell functions. It was,
therefore, of interest to study the effects of transient renal ischaemia on the abundance and distribution of two HSPs, HSP25
and HSP72, in renal tissue using Western-blot techniques. Analyses were performed on the supernatant (HSP25, HSP72) and pellet
(HSP25) of homogenates obtained from cortex (CX) and outer (OM) and inner (IM) medulla of the rat kidney immediately after
60 min of ischaemia followed by varying periods of reperfusion. Ischaemia of the left kidney caused HSP25 contents to decrease
in CX, OM and IM by 73, 89 and 54% respectively, compared with the corresponding zones of the contralateral control kidney.
This initial decrease in supernatant HSP25 was accompanied by an increased abundance of HSP25 in the pellet. Following reperfusion,
HSP25 contents in the supernatant gradually increased in CX and OM, reaching, after 24 h, values that were 5.4- and 2.5-fold
higher, respectively, than those in the control kidneys. After 7 or 14 days of reperfusion, HSP25 contents had not completely
normalised in CX, but had reached control levels in OM. In IM, the HSP25 content remained below control throughout the entire
reperfusion period. HSP72 (supernatant) was below the detection limit in the CX of the control kidney. Similar to the level
of HSP25, that of HSP72 was also markedly lower in OM and IM immediately after ischaemia. The intrarenal distribution of HSP72
and the sequence of zonal changes in HSP72 contents were similar to those observed for HSP25. These results are compatible
with the view that, during ischaemia and the initial reperfusion period, HSP25 migrates from the cytoplasmic compartment (supernatant)
into the nucleus and/or associates with cytoskeletal structures. The observation that both HSP25 and HSP72 are transiently
induced in CX and OM, but not in IM, may be explained by the fact that, while all kidney cells are exposed to ischaemic stress,
only inner medullary cells experience a major postischaemic attenuation of osmotic stress.
Received: 11 February 1997 / Received after revision and accepted: 26 March 1997 相似文献
93.
P. HAUGEN 《Acta physiologica (Oxford, England)》1982,114(2):179-186
The time course of the latency relaxation was studied at various temperatures in the range 0–26°C. Over the entire range the time of onset of the drop in tension, t1, was independent of sarcomere length. At temperatures above 12–15°C the falling phase had a point of inflexion, while at lower temperatures there was an interval during which the tension fell at a constante rate. The time when the rate of drop in tension had passed its maximum value t1,2, the time to the maximurn drop in tension t2, and the time when the tension crossed the resting level t3, all showed linear dependence on sarcomere length in the range from 2.1 to 2.7–3.4 μm. In this range the durations of the intervals t1.2-t1, t2-t1, and t3-t1 were nearly proportional to the distance from the Z-line to the end of the zone of overlap between the thick and the thin filaments. This could be explained as the activation being a longitudinal process starting from the Z-line. The slopes (dt/dS) of the linear portions of the time variables t1,2, t2, and t3 in a time-sarcomere length (S) diagram all had the same dependence on temperature giving a Q10 of 1.75. Under the assumption that the activation process followed a diffusion of calcium from the Z-line region to the zone of overlap a diffusion coefficient was estimated. At room temperature it had a magnitude of about 1/20 of that for calcium chloride in water. It had a dependence on temperature corresponding to an Arrhenius activation energy of about 37 kJ/mol which is about twice the activation energy for a simple diffusion of calcium in water. The results can be interpreted in terms of the time course of the latency relaxation mainly reflecting a longitudinal diffusion of calcium ions in the sarcoplasm. 相似文献
94.
我国正常生育力男子精浆的微量元素研究 总被引:12,自引:5,他引:7
本文报告测试了68例正常生育力成年男子精浆中的锌、铜,铁等微量元素和镁,测试结果如下:锌130±5.64μg/ml,铜1.84±0.158μg/ml,铁0.801±0.104μg/ml,镁103.86±10.01μg/ml。所测得的数值均在正常范围内。在正常范围内的精液,精浆中的锌、镁含量与精液质量(精子密度和活动力)之间无显著差异。但铜的含量与精子活动度关系密切,含量高则活动度差,反之则活动度好。铁的含量与精子密度关系也十分密切,含量高时精子密度也高。 相似文献
95.
96.
97.
Endometrial receptivity and implantation are important topics in reproductive sciences. No evidence was found to support sperm involvement in endometrial receptivity and its associated factors. This study aimed to explore the effect of the normal human spermatozoa–endometrium cell interaction in regulating genes in the endometrial receptivity pathway. Semen samples were collected from a healthy and fertile man; then, they were incubated with endometrial cells for 24 hr and considered as the sperm group. A group was cultured without spermatozoa and considered as a control group. About 24 hr later, cells were collected from the bottom of the culture dish. The expressions of the VEGF, FGF2, HBEGF, LIFR, EGF, LIF, MUC1, HOXA10, CSF and PGR genes were evaluated in the two groups. Statistical analysis was performed using an independent sample test. Compared with the control group, in the sperm group, the mRNA levels of PGR (p = .0451), VEGF (p = .0101), HBEGF (p = .0163), EFG (p = .0339), FGF2 (p = .012), LIF (p = .0324), LIFR (p = .0321) and HOXA10 (p = .0098) were significantly upregulated. The results showed that there is a need for the interaction between spermatozoa and endometrium for implantation and can be used for preparing uterine in in vitro fertilisation cycles. 相似文献
98.
Manish Kuchakulla Manish Narasimman Kajal Khodamoradi Zahra Khosravizadeh Ranjith Ramasamy 《Andrologia》2021,53(1):e13615
Spermatogenesis is the essential process to maintain and promote male fertility. It is extraordinarily complex with many regulatory elements and numerous steps. The process involves several cell types, regulatory molecules, repair mechanisms and epigenetic regulators. Evidence has shown that fertility can be negatively impacted by reduced sperm DNA integrity. Sources of sperm DNA damage include replication errors and causes of DNA fragmentation which include abortive apoptosis, defective maturation and oxidative stress. This review outlines the process of spermatogenesis, spermatogonial regulation and sperm differentiation; additionally, DNA damage and currently studied DNA repair mechanisms in spermatozoon are also covered. 相似文献
99.
《European journal of medical genetics》2023,66(1):104668
Multiple congenital anomalies-hypotonia-seizures syndrome type 1 (MCAHS1) is a rare autosomal recessive genetic disease belonging to glycosylphosphatidylinositols biosynthesis defects (GPIBD), a group of recessive disorders characterized by intellectual disability, hypotonia, and seizures. Glycosylphosphatidylinositols (GPIs) are glycolipids that anchor and remodel cell proteins. These processes are highly conserved and fundamental in the metabolism of all eukaryotes, including humans. Here, we have reported a male patient presenting with hypotonia, intellectual disability, and epilepsy, who underwent whole exome sequencing (WES). The analysis revealed the presence of two deleterious variants in PIGN that encodes GPI ethanolamine phosphate transferase-1 – one novel (c.1247_1251delAAGTG; p.Glu416Glyfs*22), and one that has been previously reported in the medical literature (c.1434+5G>A) resulting in MCAHS1. The detailed clinical assessment followed by the medical literature review also pointed out transient macrosomia and unreported in MCAHS1 advanced bone age and postnatal tall stature. These symptoms suggest that MCAHS1 shares a phenotypic overlap with disorders associated with overgrowth. To conclude, our case report and summary of the medical literature may be helpful for clinicians and geneticists who diagnose patients presenting with hypotonia accompanied by tall stature, advanced bone age, and transient macrosomia. 相似文献
100.