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71.
Cytolethal distending toxin (CDT)-producing Escherichia coli strains are considered to be a heterogeneous group of E. coli. In the present investigation, 20 CDT-producing E. coli strains, which had already been shown to be cytotoxic necrotizing factor (cnf) gene positive, were selected by PCR. Since these strains proved to be CDT producers on CHO cells but were partially characterized by PCR, they were subjected to PCR analysis to amplify the complete coding region of cdt genes. Moreover, the genetic relatedness of these strains was examined by pulse field gel electrophoresis (PFGE). To check the extent of homogeneity of these strains at the chromosomal level, tRNA insertion site analysis was performed. The CDT-producing E. coli strains under investigation were shown to be heterogeneous and diverse in regard to their genetic analysis. This observed diversity could be an independent acquisition of virulence genes that might occur through horizontal gene transfer by mobile genetic elements. This conclusion is based on the fact that data shown by tRNA insertion site analysis revealed that there is no common pattern of insertion among these isolates although they do share a common trait of CDT production.  相似文献   
72.
We present a model of cytoplasmically driven microtubule-based pronuclear motion in the single-celled Caenorhabditis elegans embryo. In this model, a centrosome pair at the male pronucleus initiates stochastic microtubule (MT) growth. These MTs encounter motor proteins, distributed throughout the cytoplasm, that attach and exert a pulling force. The consequent MT-length-dependent pulling forces drag the pronucleus through the cytoplasm. On physical grounds, we assume that the motor proteins also exert equal and opposite forces on the surrounding viscous cytoplasm, here modeled as an incompressible Newtonian fluid constrained within an ellipsoidal eggshell. This naturally leads to streaming flows along the MTs. Our computational method is based on an immersed boundary formulation that allows for the simultaneous treatment of fluid flow and the dynamics of structures immersed within. Our simulations demonstrate that the balance of MT pulling forces and viscous nuclear drag is sufficient to move the pronucleus, while simultaneously generating minus-end directed flows along MTs that are similar to the observed movement of yolk granules toward the center of asters. Our simulations show pronuclear migration, and moreover, a robust pronuclear centration and rotation very similar to that observed in vivo. We find also that the confinement provided by the eggshell significantly affects the internal dynamics of the cytoplasm, increasing by an order of magnitude the forces necessary to translocate and center the pronucleus.  相似文献   
73.
Premenstrual syndrome (PMS) includes a wide variety of physical, psychological, and cognitive symptoms that occur recurrently and cyclically during the luteal phase of the menstrual cycle and disappear soon after the onset of menstruation. Headache, often of migrainous type, is one of physical symptoms often reported in the diagnostic criteria for PMS. Menstrual migraine (MM) is a particular subtype of migraine occurring within the 2 days before and the 3 days after the onset of menses. According to this definition, therefore, some attacks of MM certainly occur in conjunction with the period of maximum exacerbation of PMS symptoms. The relationship between MM and PMS has been investigated through diary-based studies which have confirmed the possible correlation between these two conditions. In this paper we provide indications for the treatment of MM, making particular reference to those therapies that may be useful in the treatment of PMS symptoms. Even if triptans are the gold standard for the acute treatment, if symptomatic treatment is not sufficient one can resort to a short-term perimenstrual prophylaxis. Non-steroidal anti-inflammatory drugs have been demonstrated effective in MM prophylaxis. Among natural products there is some evidence of efficacy for magnesium, phytoestrogens, and ginkgolide B. Finally, also a combined oral contraceptive containing drospirenone, taken continuously for 168 days, has shown promising results.  相似文献   
74.

Background

Appendicostomy and cecostomy are two approaches for antegrade enema access for children with severe constipation or fecal incontinence as adjuncts to a mechanical bowel management program. Each technique is associated with a unique set of complications. The purpose of our study was to report the rates of various complications associated with antegrade enema access techniques to help guide which option a clinician offers to their patients.

Methods

We reviewed all patients in our Center who received an appendicostomy or cecostomy from 2014 to 2017 who were participants in our bowel management program.

Results

204 patients underwent an antegrade access procedure (150 appendicostomies and 54 cecostomies). Skin-level leakage (3% vs. 22%) and wound infections (7% vs. 28%) occurred less frequently in patients with appendicostomy compared to cecostomy. Nineteen (13%) appendicostomies required revision for stenosis, 4 (3%) for mucosal prolapse, and 1 (1%) for leakage. The rates of stenosis (33 vs. 12%) and wound infection (13 vs. 6%) were higher in patients who received a neoappendicostomy compared to an in situ appendicostomy. Intervention was needed in 19 (35%) cecostomy patients, 15 (28%) for an inability to flush or a dislodged tube, and 5 for major complications including intraperitoneal spillage in 4 (7%) and 1 (2%) for a tube misplaced in the ileum, all occurring in patients with a percutaneously placed cecostomy. One appendicostomy (1%) patient required laparoscopic revision after the appendicostomy detached from the skin.

Conclusion

Patients had a lower rate of minor and major complications after appendicostomy compared to cecostomy. The unique complication profile of each technique should be considered for patients needing these procedures as an adjunct to their care for constipation or fecal incontinence.

Type of study

Retrospective comparative study.

Level of evidence

Level III.  相似文献   
75.
BackgroundMajor reasons for long-term care insurance certification in Japan are stroke, dementia, and fracture. These diseases are reported to be associated with calcium intake. This study examined the association between calcium intake and impaired activities of daily living (ADL) using the data from NIPPON DATA90, consisting of representative sample of the Japanese population.MethodsA population-based nested case-control study was performed. A baseline survey was conducted in 1990, followed by ADL surveys of individuals ≥65 years old in 2000. Individuals with impaired ADL and selected age- and sex-matched controls were then identified. We obtained 132 pairs. Calcium intake was energy-adjusted using the residual method. The association between calcium intake and impaired ADL was examined using conditional logistic regression models. To assess the accuracy of the estimates, we conducted bootstrap analyses.ResultsThe adjusted odds ratios (ORs) for impaired ADL compared with the group with a calcium intake of <476 mg/day were 0.72 (95% confidence interval [CI], 0.37–1.40) for the 476–606 mg/day group and 0.44 (95% CI, 0.21–0.94) for the ≥607 mg/day group in 2000 (P for linear trend = 0.03). After the bootstrap analyses, the inverse relationship unchanged (median OR per 100-mg rise in calcium intake, 0.87 [1,000 resamplings]; 95% CI, 0.76–0.97).ConclusionsAfter bootstrap analyses, calcium intake was inversely associated with impaired ADL 10 years after the baseline survey.Key words: bootstrap analyses, calcium intake, impaired activities of daily living, nested case-control study, NIPPON DATA90  相似文献   
76.
Adoptive T‐cell therapy is an effective strategy for cancer immunotherapy. However, infused T cells frequently become functionally exhausted, and consequently offer a poor prognosis after transplantation into patients. Adoptive transfer of tumor antigen‐specific stem cell memory T (TSCM) cells is expected to overcome this shortcoming as TSCM cells are close to naïve T cells, but are also highly proliferative, long‐lived, and produce a large number of effector T cells in response to antigen stimulation. We previously reported that activated effector T cells can be converted into TSCM‐like cells (iTSCM) by coculturing with OP9 cells expressing Notch ligand, Delta‐like 1 (OP9‐hDLL1). Here we show the methodological parameters of human CD8+ iTSCM cell generation and their application to adoptive cancer immunotherapy. Regardless of the stimulation by anti‐CD3/CD28 antibodies or by antigen‐presenting cells, human iTSCM cells were more efficiently induced from central memory type T cells than from effector memory T cells. During the induction phase by coculture with OP9‐hDLL1 cells, interleukin (IL)‐7 and IL‐15 (but not IL‐2 or IL‐21) could efficiently generate iTSCM cells. Epstein–Barr virus‐specific iTSCM cells showed much stronger antitumor potentials than conventionally activated T cells in humanized Epstein–Barr virus transformed‐tumor model mice. Thus, adoptive T‐cell therapy with iTSCM offers a promising therapeutic strategy for cancer immunotherapy.  相似文献   
77.
A variant of large cell carcinoma showing a rhabdoid phenotype, which is rare among primary lung cancers, is presented. A 59-year-old man was admitted to hospital for an operation. Computed tomography scans showed a mass with a smooth border, invading the thoracic wall. A right upper lobe lobectomy was carried out with resection of a part of the thoracic wall. Pathological examination showed that the tumor was mostly composed of cells with prominent eosinophilic cytoplasmic globules and giant cells, which did not adhere to each other. Cytologically, the tumor cells contained nuclei with a reticular chromatin pattern and one to two prominent nucleoli, and hyaline-like and reticular inclusion bodies, which were immunohistochemically positive for vimentin, but not for alpha-smooth muscle actin, myoglobin or pan-actin. Radiological and laboratory examinations did not detect the presence of the tumor in other organs, indicating that the primary lesion was not situated elsewhere. Metastasis to the right adrenal gland was observed 1 year and 4 months after the operation; however, the patient has been free of the disease 3 years and 11 months after the second operation of an adrenalectomy. This case showed a relatively good prognosis, which is rare among rhabdoid tumors of various organs that generally have poor prognoses with rapid, fatal progression.  相似文献   
78.
79.
Enteropathogenic Escherichia coli (EPEC) comprise one of the six categories of diarrhoeagenic E. coli (DEC). EPEC is subgrouped into typical (tEPEC) and atypical (aEPEC). The identification of DEC cannot be based only on cultural and biochemical criteria, since they are indistinguishable from the non-pathogenic E. coli commonly found in human feces. Several PCR methods, with both single and multiple target genes, have been reported for detecting the different DEC pathotypes. In the present study five hundred E. coli isolates from children with diarrhea were subjected into multiplex PCR. Furthermore the strains were typed serologically with O antisera and their fliC gene was characterized by PCR-RFLP. The results obtained revealed that overall 41 (8.2%) isolates could be detected as EPEC by this multiplex PCR assay. Of these isolates; 27 (66%) were typical (escv+, bfp+) and 14 (34%) atypical EPEC (escv+, bfp-). None of these 41 isolates contained the Stx1 and Stx2 genes. Among 37 (90%) typeable strains, nine different serogroups were present. The most common serogroups were O111, followed by O86, O55 and O119 and 10 different H types were found among these isolates. The multiplex PCR assay was found to be rapid and reliable in comparison to serological test; especially when screening the large number of isolates.  相似文献   
80.
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