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1.
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   
2.
Primary ciliary dyskinesia (PCD) is a disorder of structure and function of motor ciliary and dyskinetic activity of ciliary in the fallopian tubes of affected women and could lead to infertility in some cases. In vitro fertilisation (IVF) is a choice of treatment in infertile women with PCD, which could conquer the tubal dysfunction. In this case study, we report a PCD affected woman with infertility who was treated by IVF and pregnancy was achieved but it failed due to the spontaneous abortion. We also performed whole-exome sequencing for this case and her PCD-affected sister, which did not reveal any genetic abnormality related to the PCD or infertility.  相似文献   
3.
MUSASHI (MSI) family plays the main role in the spermatogenesis process. The purpose of this study was the assessment of sperm MSI1 and MSI2, and sperm functional tests in infertile men (n = 30) with varicocele and fertile men (n = 30). Furthermore, MSI1 and MSI2 proteins were assessed in testicular tissue of azoospermic men (n = 9) as well as epididymal spermatozoa and testis of mice. Expression of MSI1 and MSI2 was assessed at RNA and protein levels in human spermatozoa. Sperm concentration and motility were significantly lower, while abnormal sperm morphology, lipid peroxidation, DNA fragmentation and protamine deficiency were significantly higher in men with varicocele compared to fertile individuals. Any significant difference was not observed in the expression of MSI1 and MSI2 mRNA between the two groups. Unlike MSI1 protein that was not detectable in humans, the relative expression of MSI2 protein was similar in varicocele and fertile individuals. The expression level of both Msi1 and Msi2 proteins was also observable in mouse spermatozoa. No significant relationship was observed between sperm functional parameters with expression of these genes. The data of this study demonstrated that although MSI1 and MSI2 play important roles during spermatogenesis, their relative expression in spermatozoa was not affected by varicocele.  相似文献   
4.
5.
The rabbit fish is an economically valuable teleost species which lives in shallow coastal waters amongst aquatic plants. Two species of rabbit fish, Siganus sutore and Siganus javus, have been identified in the sea south of Iran. In this study, in order to investigate the histology of the outer layer of the S. javus eye, the eyes of 12 healthy specimens of S. javus were extracted and histologic sections were prepared. The sections were studied under a light microscope after staining with hematoxylin and eosin and Masson's trichrome stains. The outer layer was composed of the cornea cranially and the sclera caudally. The sclera contained an episclera zone and two cartilaginous segments with connective tissue correlation. The cornea included dermal components (stratified cuboidal epithelium, Bowman's membrane, and dermal stroma with occasional flattened cells); the scleral part consisted of two main layers (irregular fibers of connective tissue overlaying the second scleral stroma layer). The fibers of the scleral stroma were the only component present at the posterior part of the cornea. These results reveal that the eye of S. javus does not possess Descemet's membrane or endothelium in the cornea.  相似文献   
6.
Objective: Vasoconstriction during anxiety reduces fetal oxygenation and leads to hypoxia. Hypoxia in turn results in increase of the number of nucleated red blood cells (NRBCs) in the cord blood. The present study aimed to assess the effect of decreasing maternal anxiety on fetal oxygenation and NRBCs count in the cord blood. Methods:. In this study, 150 women were randomly divided into two intervention groups [supportive care and acupressure in BL32 (bladder) acupoint] and a control group (hospital routine care). The infants'' cord blood was investigated regarding the number of NRBCs and the intensity of hypoxia after birth. Then, the data were entered into the SPSS statistical software (v. 16) and analyzed using ANOVA, Chi-square test, and logistic regression analysis. Findings : The significant difference was found between the two groups regarding the number of NRBCs counted in the peripheral blood smear (P<0.001). Besides, a significant relationship was observed between the length of the first and second stages of labor and the number of NRBCs in the cord blood (P=0.01). Also, a significant association was observed between the type of delivery and the number of NRBCs in the cord blood in both intervention (P<0.001) and control groups (P=0.03). Conclusion: Doula supportive care and acupressure at BL32 point reduced the length of labor stages as well as the anxiety level. Also, nucleated red blood cells were less in the 2 groups of intervention than in control group. Regarding the fact that nucleated red blood cells cannot be the only factor for hypoxia predicting, for affirmation of this theory study with higher sample size and survey of mothers at high risk are needed.Key Words: Acupressure; Anxiety; Delivery Outcome; Doula  相似文献   
7.
We successfully synthesized VS2–NiS2 hybrid nanostructures via a one-pot hydrothermal technique. Microstructural characterizations were carried out by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), UV-visible spectroscopy, and Fourier transform infrared spectroscopy (FTIR). The optical indexes such as n, k, and ε were assessed based on the reflectance spectra data and Kramers–Kronig method. By adding varying amounts of the NiS2 phase in the hybrid nanostructure, the morphology of the hybrid nanostructures is altered to produce microflowers, nanoflakes, and nanoflowers. These changes affect the nonlinear optical properties. The third order nonlinear optical parameters (n2, β) were analyzed via a simple and accurate Z-scan technique using different laser powers. The two-photon absorption phenomenon has a significant enhancement effect on the nonlinear absorption process, but the nonlinear refractive behaviour of the different hybrid nanostructures changes from self-defocusing to self-focusing due to the alteration of the electronic state alignment and morphology. The magnitudes of n2 and β are in the order of 10−9 cm2 W−1 and 10−3 cm W−1, respectively. The increasing of the density of states of electrons leads to the improvement of the nonlinear optical responses of the VS2–NiS2 hybrid nanostructures in comparison with the pure VS2 structure. This study demonstrates the great potential of this hybrid nanostructure for optical limiters and modulators as well as photonic devices.

Increasing of the density of states of electrons is an important criterion in nonlinear optical phenomena. The hybridization of VS2 with NiS2 leads to the improvement of nonlinear optical properties using in the optical and photonic applications.  相似文献   
8.

Research question

Telomeres are non-coding, repetitive DNA sequences (TTAGGG repeats) that play an important role in maintaining genome integrity. Unlike in somatic cells, telomere length in spermatozoa increases with male age and is considered as a molecular marker of sperm quality. The aetiology of failed fertilization following intracytoplasmic sperm injection (ICSI) is multifactorial; perhaps one of the reasons for this failure in these individuals is shortened sperm telomere length. This study therefore aimed to assess sperm telomere length in addition to DNA damage, lipid peroxidation and protamine deficiency in infertile men with previously failed/low fertilization post-ICSI.

Design

Semen samples were obtained from infertile men with previous failed/low fertilization rates (n?=?10). Chromatin integrity (chromomycin A3 staining and TUNEL assay), lipid peroxidation (BODIPY probe) and telomere length (real-time PCR) for semen samples from these men were compared with samples obtained from fertile individuals (n = 10).

Results

The results showed significantly higher mean values for sperm DNA damage, lipid peroxidation and reduced telomere length in spermatozoa of infertile men with previous failed/low fertilization compared with fertile individuals (P < 0.05).

Conclusions

Failed/low fertilization rates could be related to oxidative stress resulting in short telomere length, and also increased sperm chromatin damage and lipid peroxidation. From literature sources, shortened telomere length may lead to detachment of chromosomes from the nuclear membrane, the consequences of which are defects in the process of spermatogenesis, pronuclei formation, and delayed or arrested cell cycle post-ICSI.  相似文献   
9.
DNA fragmentation in human sperm has been related to endogenous and exogenous factors. Exogenous factors can also affect leukocyte DNA integrity. This study evaluated the relation between sperm DNA damage and leukocyte DNA integrity, as a predictor of exogenous factors. DNA damage in the sperm and leukocytes of 41 individuals undergoing ICSI were measured by Comet assay. In addition, sperm chromatin dispersion (SCD) was carried out on semen samples. A positive correlation was observed between the DNA integrity of sperm with leukocytes. When patients were divided into low and high DNA exposure groups, sperm DNA fragmentation was significantly different between the two groups. Cleavage rate and embryo quality showed significant correlation with leukocyte DNA integrity. The results showed that leukocyte DNA integrity could be used to identify individuals at high risk in order to reduce the extent of DNA damage in patients before ICSI in order to improve the subsequent outcome of this procedure.  相似文献   
10.
AIM: To improve our understanding of Iranian regional variation in Helicobacter pylori (H. pylori ) antibiotic resistance rates to find the best antibiotic therapy for eradication of H. pylori infections.METHODS: A total of 266 patients undergoing endoscopy in Shiraz, Southern Iran, were included in this study. H. pylori strains were isolated from antral biopsies by culture and confirmed by the rapid urease-test and gram staining. Antibiotic susceptibility of H. pylori isolates was determined by E-test.RESULTS: A total of 121 H. pylori strains were isolated, 50 from male and 71 from female patients. Data showed that 44% (n = 53), 20% (n = 24), 5% (n = 6), and 3% (n = 4) of all strains were resistant to the antibiotics metronidazole, amoxicillin, clarithromycin, and tetracycline, respectively. When the antibiotics were considered together we found 11 sensitivity patterns for the strains. Resistance to metronidazole was significantly higher in female than in male patients (P < 0.05). In about 71% of the metronidazole-resistant isolates, the minimum inhibitory concentrations (MICs) exceeded 256 μg/mL.CONCLUSION: We found a moderate rate of primary resistance to metronidazole. However, a high MIC (> 256 mg/L) which was found in 71% of the isolates is considerable. In the case of amoxicillin, an increased resistance rate of 20% is worrying. Resistance to clarithromycin and tetracycline is also emerging among the H. pylori strains in our region.  相似文献   
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