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21.
Elham Barkhordari Nima Rezaei Bita Ansaripour Pegah Larki Maryam Alighardashi Hamid Reza Ahmadi-Ashtiani Mahdi Mahmoudi Mohammad-Reza Keramati Peiman Habibollahi Mohammad Bashashati Naser Ebrahimi-Daryani Ali Akbar Amirzargar 《Journal of clinical immunology》2010,30(1):74-79
Introduction
Irritable bowel syndrome (IBS) is a multifactorial functional gastrointestinal disorder, characterized by recurrent abdominal pain and altered bowel habits. Proinflammatory cytokines can play an important role in intestinal inflammation, while their production is under genetic control.Methods
This study was performed in a group of patients with IBS to analyze the genotype frequencies of a number polymorphic genes coding for proinflammatory cytokine (interleukin-6 (IL), tumor necrosis factor-alpha (TNF-α), and IL-1 group). Using polymerase chain reaction with sequence-specific primers method, the cytokine genes were amplified, and alleles and genotypes of 71 patients with IBS were detected on gel electrophoresis, and the results were compared with healthy control subjects.Results
Results of the analyzed data showed that the frequencies IL-1R C allele at position Pst-I 1970 (P?=?0.017), IL-6 G allele at position ?174 (P?=?0.002), and TNF-α G allele at position ?238 (P?<?0.001) in the patient group were significantly higher than the control group. IL-6 GG genotype (?174) and TNF-α GG genotype (?238) in the patient group were also significantly overrepresented (P?<?0.001), while IL-6 CG genotype (?174) and TNF-α GA genotype (?238) were significantly decreased in the patients with IBS (P?<?0.001). The frequencies of IL-6 (?174, nt565) GG haplotype and TNF-α (?308, ?238) GG haplotype were also significantly higher in the patient group (P?<?0.001), whereas the frequencies of the haplotypes IL-6 CG and TNF-α GA were significantly decreased in the patients with IBS (P?<?0.001).Conclusion
IL-6 and TNF-alpha proinflammatory cytokine gene polymorphisms could change individual susceptibility to IBS and might have a role in pathophysiology of disease. 相似文献22.
Bahia Namavar Jahromi Jaleh Zolghadri Elham Rahmani Shohreh Alipour Zahra Anvar Afsun Zarei Pegah Keramati 《Taiwanese journal of obstetrics & gynecology》2019,58(2):255-260
Objective
Ovarian hyperstimulation syndrome (OHSS) is a major complication of assisted reproductive technologies (ART). Polycystic ovary syndrome (PCOS) is a risk factor for OHSS. The aim of this randomized clinical trial (RCT) was to study the effect of low-dose aspirin (LDA) on the development of OHSS and ART outcomes in PCOS during ART.Materials and methods
This double-blinded placebo controlled RCT was performed on 232 PCOS infertile women in their first ART cycles during 2010–2016. LDA and placebo capsules were prepared, packed and specified by code numbers in similar shapes. One package was given to every woman and asked to take one capsule/day since the 21st day of her cycle prior to the gonadotropin stimulation. Gonadotropin releasing hormone agonist long protocol and triggering by human chorionic gonadotropin were used. Development of moderate to severe OHSS and their ART outcomes were documented then the codes were broken and data analyzed. Chi-square and Mann–Whitney U tests were used for the statistical analyses.Results
Eighteen cases that did not follow the study design were excluded. 214 cycles remained for the final analyses with 109 cases in LDA and 105 in the placebo group. Rate of the moderate to severe OHSS in LDA group was 34.9% compared to 30.5% in placebo group (P = 0.494). Fertilization rate was 71.8% vs 65.1% (P = <0.001) and the mean number of grade III embryos were 3.28 ± 3.53 vs 1.46 ± 1.42 (P = 0.014) in LDA and placebo groups, respectively. The mean number of the oocytes in different grades, total and frozen embryos also implantation and clinical pregnancy rates were not different between the groups.Conclusion
Moderate to Severe OHSS was not decreased but fertilization rate and the mean number of poor quality embryos were increased in LDA arm.Registration number
IRCT 201105216541N1. 相似文献23.
DL?MagerEmail author AD?Haffajee PM?Devlin CM?Norris MR?Posner JM?Goodson 《Journal of translational medicine》2005,3(1):27
Background
The purpose of the present investigation was to determine if the salivary counts of 40 common oral bacteria in subjects with an oral squamous cell carcinoma (OSCC) lesion would differ from those found in cancer-free (OSCC-free) controls. 相似文献24.
Debelenko LV; Brambilla E; Agarwal SK; Swalwell JI; Kester MB; Lubensky IA; Zhuang Z; Guru SC; Manickam P; Olufemi SE; Chandrasekharappa SC; Crabtree JS; Kim YS; Heppner C; Burns AL; Spiegel AM; Marx SJ; Liotta LA; Collins FS; Travis WD; Emmert-Buck MR 《Human molecular genetics》1997,6(13):2285-2290
Lung carcinoids occur sporadically and rarely in association with multiple
endocrine neoplasia type 1 (MEN1). There are no well defined genetic
abnormalities known to occur in these tumors. We studied 11 sporadic lung
carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene
on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy
fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was
studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene
were inactivated. All four tumors showed the presence of a MEN1 gene
mutation and loss of the other allele. Observed mutations included a 1 bp
insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide
substitution affecting a donor splice site. Each mutation predicts
truncation or potentially complete loss of menin. The remaining seven
tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH.
The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a
complex germline MEN1 gene mutation. The data implicate the MEN1 gene in
the pathogenesis of sporadic lung carcinoids, representing the first
defined genetic alteration in these tumors.
相似文献
25.
Fifty women with polycystic ovaries took part in a prospective randomized
study. All women required treatment by in-vitro fertilization (IVF) for
reasons other than anovulation. They had all previously undergone ovarian
stimulation with gonadotrophin therapy which had failed to result in
pregnancy or had been abandoned due to high risk of developing ovarian
hyperstimulation syndrome (OHSS). Twenty-five women were treated by
long-term pituitary desensitization followed by gonadotrophin therapy,
oocyte retrieval and embryo transfer (group 1). Twenty-five women underwent
laparoscopic ovarian electrocautery after pituitary desensitization
followed by gonadotrophin therapy, oocyte retrieval and embryo transfer
(group 2). A significantly higher number of women in group 1 had to have
the treatment cycle abandoned due to impending or actual OHSS, determined
by endocrine and clinical findings. In addition, the development of
moderate or severe OHSS in completed cycles was higher in group 1. The
pregnancy rate and miscarriage rates in the two treatment groups were
similar. The authors propose that laparoscopic ovarian electrocautery is a
potentially useful treatment for women who have previously had an IVF
treatment cycle cancelled due to risk of OHSS or who have suffered OHSS in
a previous treatment cycle.
相似文献
26.
The bias favoring deletion over inversion in DH-JH rearrangement has been
known for years, but the underlying mechanism has yet to be fully defined.
It has been suggested that the ratio of deletion/inversion is determined by
the combined effect of two factors: (i) the relative strengths of 5' and 3'
recombination signal sequences (RSS) of a DH segment, and (ii) the
efficiency with which the deletional product (one joint) forms relative to
the inversional product (two joints). In this study, we analyzed for the
first time the effect of factor 1 alone on the biased 3' RSS utilization in
DH-JH joining by using deletional plasmids in an extrachromosomal substrate
V(D)J recombination assay. It was found that the 3' RSS and associated
coding end (12 bp) mediate recombination more efficiently than the 5'
RSS/coding end DH-JH plasmids. These results demonstrate that the effect of
the RSS/coding end alone can account, at least partially, for the
predominant deletion in DH-JH recombination. The potential effect of the
relative strength of RSS and associated coding end on the ordered
rearrangement of DH-JH followed by VH to DH-JH was also assessed. When
recombination frequencies of D-->J (3' DH to J3) were compared with
frequencies of V-- >D (VHPJ14 to 3' DH or VHOX2 to 3' DH), it was found
that V-->D joining was, if anything, more efficient than D-->J
joining. Therefore, if all three segments were accessible, RSS/coding end
effects would not contribute to the ordered rearrangement of the IgH locus.
相似文献
27.
Behrooz Nikahval Seifollah Dehghani Nazhvani Mohammad Hadi Bagheri Nader Tanideh Mehrangiz Keramati Hamid Reza Gheisari 《Comparative clinical pathology》2012,21(6):1451-1456
The objectives of the present study were to describe radiographic and magnetic resonance imaging (MRI) findings of early osteoarthritis and their relationships at the same time. A total number of ten rabbits were used and randomly divided into two equal groups. In one group, cranial cruciate ligament (CCL) of the left knee was transected to produce experimental osteoarthritis and in the other group, only the articular capsule was entered as sham operation (arthrotomy group). All of the left knees were examined by MRI and radiography before operation to exclude preexisting abnormalities and serve as control. One month postoperation, two conventional radiographic views and MR imaging were performed under general anesthesia. Statistical analysis of the MRI results revealed that there was a significant difference between the CCL-transected group with arthrotomy and control groups. There was no significant difference in the radiographic findings between the operated, arthrotomy and control groups. It was concluded that osteoarthritic changes of the joints can be detectable 1?month postinjury by MRI. Meniscal degeneration and subchondral bone irregularity are detectable diagnostic signs. 相似文献
28.
In vitro evidence for both the nucleus and cytoplasm as subcellular sites of pathogenesis in Huntington's disease 总被引:6,自引:1,他引:6
A unifying feature of the CAG expansion diseases is the formation of
intracellular aggregates composed of the mutant polyglutamine-expanded
protein. Despite the presence of aggregates in affected patients, the
precise relationship between aggregates and disease pathogenesis is
unresolved. Results from in vivo and in vitro studies of mutant huntingtin
have lead to the hypothesis that nuclear localization of aggregates is
critical for the pathology of Huntington's disease (HD). We tested this
hypothesis using a 293T cell culture model system that compared the
frequency and toxicity of cytoplasmic and nuclear huntingtin aggregates. We
first assessed the mode of nuclear transport of N-terminal fragments of
huntingtin, and show that the predicted endogenous NLS is not functional,
providing data in support of passive nuclear transport. This result
suggests that proteolysis is a necessary step for nuclear entry of
huntingtin. Additionally, insertion of nuclear import or export sequences
into huntingtin fragments containing 548 or 151 amino acids was used to
reverse the normal localization of these proteins. Changing the subcellular
localization of the fragments did not influence their total aggregate
frequency. There were also no significant differences in toxicity
associated with the presence of nuclear compared with cytoplasmic
aggregates. The findings of nuclear and cytoplasmic aggregates in affected
brains, together with these in vitro data, support the nucleus and cytosol
as subcellular sites for pathogenesis in HD.
相似文献
29.
30.
Differentiation of thrombi from slow flow in the pulmonary arteries, sometimes observed in the presence of pulmonary arterial hypertension, can be equivocal. Magnetic resonance (MR) imaging was performed in a patient with chronic pulmonary thromboembolism and pulmonary arterial hypertension using an electrocardiographically gated technique that allowed visualization of the pulmonary arteries at the end of diastole and multiple times during systole. These images were compared with those of a patient with primary pulmonary hypertension and those of healthy subjects. Thrombi were discrete structures, seen throughout the cardiac cycle on both the first and second spin-echo images, and decreased in signal intensity on the second image. Slow flow increased in signal intensity and changed in structure during the cardiac cycle and was seen best on the second image. MR may play an important role in excluding large central thrombi as the cause of pulmonary arterial hypertension. It is a noninvasive method for defining pulmonary arterial wall thickness and for direct visualization of chronic pulmonary thrombus. 相似文献