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41.
42.

Objective

The etiology of recurrent spontaneous abortions (RSA) in chromosomally normal parents is still unexplained. It is unclear whether or not some factors, such as spontaneous abortions (SA), which occur among extended family members can create a predisposition to RSA. Therefore, this study comprises two parts: (a) an epidemiological part, to evaluate the relationship between RSA in 567 couples and the frequency of SA among their first (I), second (II) and third (III) generation relatives, and (b) a genetic part, investigating whether parental and fetal chromosomal status may predispose to the occurrence of RSA.

Study design

Couples (567) having one or more SA were analyzed in this retrospective case-control study. The family reproductive history data was collected from their medical charts.

Results

The total number of SA found in 567 couples was 1174, and the largest number occurred at 8–10 weeks of gestation. The majority of spouses had normal karyotypes (88.5% and 91%). Of the remainder, 65% of females and 76% of males expressed constitutional chromosomal variation, mostly pericentric inversion of chromosome 9. Cytogenetic analysis of aborted material showed some type of change in 40% of cases. The family reproductive history data indicated that SA among the couples’ I, II and III generation relatives happened with a frequency two to three times higher than that of the general population (55.5, 47.6 and 32.6% for female relatives, and 45.8, 44.1 and 15.1% for male relatives).

Conclusion

Positive reproductive family history for SA might be the causal factor for RSA and can also predetermine women that are of greater susceptibility to preterm pregnancy.  相似文献   
43.

Objective

Sperm parameters, particularly motility, decrease during cryopreservation. Theophylline generally enhances sperm motility. We analyzed effects of theophylline and freezing on sperm motility.Design: Experimental study.Setting: Private IVF lab.Setting: IVF lab of Mehrgan Hospital.

Method

22–55 year-old men participated in this study (30 fresh ejaculation and 8 TESE samples). After sperm analysis, we added theophylline (40 mM) to half of our samples as case group to compare motility with the remaining samples as control group. Cryopreservation was performed in two groups. After thawing, motility of both groups was recorded. Furthermore, theophylline (40 mM) was applied to both groups after thawing again.

Result

After adding theophylline, sperm motility improved significantly in all samples. Sperm motility reduced in control group more than the study group after freeze-thaw procedure (P < 0.002, normal morphology <5%). Sperm motility was not enhanced significantly by re-adding of theophylline to the two groups. Interactions between stages and groups were statistically significant in semen and biopsy samples (p < 0.001).

Conclusion

Adding theophylline before freezing can preserve motility of sperms in samples with different parameters and even sperms extracted in testicular biopsy. Theophylline may have protective impact on sperms in freezing procedure.  相似文献   
44.
Background: Respiratory distress syndrome (RDS) is a severe pulmonary disease predominantly affects preterm newborns. Polymorphisms of surfactant-protein genes have been mostly evaluated as the candidate contributors in genetics of RDS. However the results are divers in different studies. We aimed at investigating the association of surfactant protein B (SPB) gene 9306 A/G polymorphism (rs7316) with RDS development.

Method: Three hundred and eighty newborns with gestational age of less than 34 weeks were included in a multicenter case–control study. Respiratory distress (RD) was scored according to Downes’ scoring system. Polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) method was used for genotyping.

Result: One hundred and eighty-four neonates showed RDS and 196 did not. Gestational age (GA) was significantly lower in the RDS group compared with the controls. AA genotype and A allele were found more frequently in the RDS group than the controls (96.2% versus 63.8% and 98.1% versus 80.6%, respectively) (p =.0001).

Conclusions: This is the first report of association of SFTPB rs7316 polymorphism with RDS development in Iranian newborns. The current study suggests that GA <28-weeks is the most important factor in predisposition to RDS. Genetic background in terms of SP-B gene might be involved in predisposition to RDS in premature neonates.  相似文献   

45.
46.
One of the most common orthopedic injuries in the general population, particularly among athletes, is ankle sprain. We investigated the literature to evaluate the known pre- and postoperative biomechanical changes of the ankle after anatomic lateral ligament repair in patients suffering from chronic ankle instability. In this systematic review, studies published till January 2020 were identified by using synonyms for “kinetic outcomes,” "kinematic outcomes,” “Broström procedure,” and “lateral ligament repair.” Included studies reported on pre- and postoperative kinematic and/or kinetic data. Twelve articles, including 496 patients treated with anatomic lateral ligament repair, were selected for critical appraisal. Following surgery, both preoperative talar tilt and anterior talar translation were reduced similarly to the values found in the uninjured contralateral side. However, 16 of 152 (10.5%) patients showed a decrease in ankle range of motion after the surgery. Despite the use of these various techniques, there were no identifiable differences in biomechanical postoperative outcomes. Anatomic lateral ligament repair for chronic ankle instability can restore ankle biomechanics similar to that of healthy uninjured individuals. There is currently no biomechanical evidence to support or refute a biomechanical advantage of any of the currently used surgical ligament repair techniques mentioned among included studies.  相似文献   
47.
Previous studies have indicated an association between diabetes mellitus and impairments in synaptic plasticity in the hippocampus. However, it is not clear if the impairments of synapses are pre- or post-synaptic or both. The aim of this study was to evaluate the extracellular basal levels of glutamate and GABA at dentate gyrus of anesthetized streptozotocin-induced diabetic rats, after 12 weeks of diabetes induction. Extracellular levels of glutamate and GABA were investigated by using the microdialysis technique coupled to high performance liquid chromatography (HPLC) with fluorescent detection. Experimental groups were the control group and the diabetes group. The results showed that glutamate levels were significantly decreased in diabetes group compared to the control group, while GABA levels showed no changes. The findings support the possibility that alterations in transmission may account, in part, for synaptic plasticity deficits induced in diabetes.  相似文献   
48.
Two species of Leishmania (L), L. tropica and L. major, are among the main causative agents of cutaneous leishmaniasis. Arginase (ARG) is an essential enzyme for cell growth, thus an attractive drug target. In this study, we tried to survey the inhibitory impact of ARG by nor-NOHA (N-ω-hydroxy-L-nor-arginine) on in vivo infection caused by L. tropica. BALB/c mice were inoculated with L. tropicaEGFP-LUC (Ltrop) or L. majorEGFP-LUC (Lmj) and then were treated by nor-NOHA. ARG inhibitor only indicated a delay in generation of a cutaneous lesion in inoculated footpad with nor-NOHA-Ltrop and nor-NOHA-Lmj. ARG activity has been significantly reduced in nor-NOHA-Ltrop group. In this group, ARG activity inhibition correlated with increased levels of nitric oxide (NO). In both inoculated mice with Ltrop or Lmj, parasite load showed a significant decrease at later steps during the CL course post-treatment. In vivo bioluminescence intensity did not show any ARG's inhibitory effect on treated-Ltrop. The findings verified that the ARG activity may partially control the L. tropica infection in BALB/c mice through reduction of parasite proliferation and parasite killing through NO generation. This effect is dose-dependent.  相似文献   
49.

Phenylketonuria (PKU), one of the most common inborn errors of amino acid metabolism, is caused by mutations in the phenylalanine hydroxylase (PAH) gene (PAH). PKU has wide allelic heterogeneity, and over 600 different disease-causing mutations in PAH have been detected to date. Up to now, there have been no reports on the minihaplotype (VNTR/STR) analysis of PAH locus in the Iranian population. The aims of the present study were to determine PAH mutations and minihaplotypes in Iranian families with PAH deficiency and to investigate the correlation between them. A total of 81 Iranian families with PAH deficiency were examined using PCR-sequencing of all 13 PAH exons and their flanking intron regions to identify sequence variations. Fragment analysis of the PAH minihaplotypes was performed by capillary electrophoresis for 59 families. In our study, 33 different mutations were found accounting for 95% of the total mutant alleles. The majority of these mutations (72%) were distributed across exons 7, 11, 2 and their flanking intronic regions. Mutation c.1066-11G > A was the most common with a frequency of 20.37%. The less frequent mutations, p.Arg261Gln (8%), p.Arg243Ter (7.4%), p.Leu48Ser (7.4%), p.Lys363Asnfs*37 (6.79%), c.969 + 5G > A (6.17%), p.Pro281Leu (5.56), c.168 + 5G > C (5.56), and p.Arg261Ter (4.94) together comprised about 52% of all mutant alleles. In this study, a total of seventeen PAH gene minihaplotypes were detected, six of which associated exclusively with particular mutations. Our findings indicate a broad PAH mutation spectrum in the Iranian population, which is consistent with previous studies reporting a wide range of PAH mutations, most likely due to ethnic heterogeneity. High prevalence of c.1066-11G > A mutation linked to minihaplotype 7/250 among both Iranian and Mediterranean populations is indicative of historical and geographical links between them. Also, strong association between particular mutations and minihaplotypes could be useful for prenatal diagnosis (PND) and preimplantation genetic diagnosis (PGD) in affected families.

  相似文献   
50.

Background:

Evaluation of myocardial function by speckle-tracking echocardiography is a new method for the early diagnosis of systolic dysfunction.

Objectives:

We aimed to determine myocardial speckle-tracking echocardiography indices in Kawasaki Disease (KD) patients and compare them with the same indices in control subjects.

Patients and Methods:

Thirty-two patients (65.5% males) with KD and 19 control subjects with normal echocardiography participated in this study. After their demographic characteristics and clinical findings were recorded, all the participants underwent transthoracic echocardiography. Strain (S), Strain Rate (SR), Time to Peak Strain (TPS), and Strain Rate (TPSR), longitudinal velocity and view point velocity images in the two, three, and four-chamber views were semi-automatically obtained via speckle-tracking echocardiography.

Results:

Among the patients, Twenty-four cases (75%) were younger than 4 years. Mean global S and SR was significantly reduced in the KD patients compared to controls (17.03 ± 1.28 vs. 20.22 ± 2.14% and 1.66 ± 0.16 vs. 1.97 ± 0.25 1/second, respectively), while there were no significant differences regarding mean TPS, TPSR, longitudinal velocity and view point velocity. Using repeated measure of analysis of variances, we observed that S and SR decreased from base to apical level in both groups. The change in the pattern of age adjusted mean S and SR across levels was significantly different between the groups (P < 0.001 for both parameters).

Conclusions:

We showed changes in S and SR assessed in KD patients versus control subjects in the acute phase of KD. However, we suggest that further studies be undertaken to compare S and SR in the acute phase and thereafter in KD patients.  相似文献   
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