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Pathogens in the gastrointestinal tract exist within a vast population of microbes. We examined associations between pathogens and composition of gut microbiota as they relate to Shigella spp./enteroinvasive Escherichia coli infection. We analyzed 3,035 stool specimens (1,735 nondiarrheal and 1,300 moderate-to-severe diarrheal) from the Global Enteric Multicenter Study for 9 enteropathogens. Diarrheal specimens had a higher number of enteropathogens (diarrheal mean 1.4, nondiarrheal mean 0.95; p<0.0001). Rotavirus showed a negative association with Shigella spp. in cases of diarrhea (odds ratio 0.31, 95% CI 0.17–0.55) and had a large combined effect on moderate-to-severe diarrhea (odds ratio 29, 95% CI 3.8–220). In 4 Lactobacillus taxa identified by 16S rRNA gene sequencing, the association between pathogen and disease was decreased, which is consistent with the possibility that Lactobacillus spp. are protective against Shigella spp.–induced diarrhea. Bacterial diversity of gut microbiota was associated with diarrhea status, not high levels of the Shigella spp. ipaH gene.  相似文献   
83.
BACKGROUND AND AIM: Gastric and enteric Helicobacter species have been associated with the pathogenesis of some extragastric diseases. METHODS: We retrospectively investigated the presence of DNA of Helicobacter species in samples of the cancer and the surrounding tumour-free liver tissues of patients with hepatocellular carcinoma (HCC, n=12) and cholangiocarcinoma (CC, n=13). The patients were from an area with low liver cancer incidence and with low hepatitis B and C prevalence. Patients with a benign liver disease (n=24) were included as controls. Paraffin-embedded liver samples were examined by a Helicobacter genus-specific PCR assay as well as group-specific PCR assays for Enterobacteriaceae, Bacteroides, Lactobacillus and Enterococcus. PCR products of positive samples were characterised by denaturing gradient gel electrophoresis (DGGE) and DNA sequencing. RESULTS: PCR assay detected Helicobacter DNA in seven of 12 (58%) and eight of 13 (62%) normal liver tissue specimens from HCC and CC patients, respectively. Two cancer samples from HCC patients were Helicobacter-positive but none of the CC cancers. In the control group, three of 24 (12.5%) patients with a benign liver condition were positive for Helicobacter species (p<0.01 compared to results of tumour-free liver tissue from the cancer patients). DGGE and DNA sequence analysis showed that 90% of the detected PCR products were "H. pylori-like". DNA of some other enteric bacteria was detected in the liver of one cancer patient and one control (4% of all patients). CONCLUSION: The presence of DNA of Helicobacter species in liver specimens, but not of other common gut bacteria, was associated with human hepatic carcinogenesis.  相似文献   
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Monitoring recovery from diaphragm paralysis with ultrasound   总被引:1,自引:0,他引:1  
BACKGROUND: Diaphragmatic paralysis is an uncommon, yet underdiagnosed cause of dyspnea. Data regarding the time course and potential for recovery has come from a few small case series. The methods that have been traditionally employed to diagnose diaphragmatic weakness or paralysis are either invasive or limited in sensitivity and specificity. A new technique utilizing two-dimensional, B-mode ultrasound (US) measurements of diaphragm muscle thickening during inspiration (Deltatdi%) has been validated in the diagnosis of diaphragm paralysis (DP). The purpose of this study was to assess whether serial US evaluation might be utilized to monitor the potential recovery of diaphragm function. METHODS: Twenty-one consecutive patients with clinically suspected DP were referred to the pulmonary physiology laboratory. Sixteen patients were found to have DP by US (unilateral, 10 patients; bilateral, 6 patients). Subjects were followed up for up to 60 months. On initial and subsequent visits, Deltatdi% was measured by US. Additional measurements included upright and supine vital capacity (VC), maximal inspiratory pressure (Pimax), and maximal expiratory pressure. RESULTS: Eleven of 16 patients functionally recovered from DP. The mean (+/- SD) recovery time was 14.9 +/- 6.1 months. No diaphragm thickening was noted in those patients who did not recover. Positive correlations were found between improvement in Deltatdi% and interval changes in VC, Pimax, and end-expiratory measurements of diaphragm thickness. CONCLUSIONS: US may be used to assess for potential functional recovery from diaphragm weakness or DP. As in previous series, recovery occurs in a substantial number of individuals, but recovery time may be prolonged.  相似文献   
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Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited myocardial disease that predominantly affects the right ventricle and is associated with ventricular arrhythmias that may lead to sudden cardiac death. Mutations within at least seven separate genes have been identified to cause ARVC, however a genetic culprit remains elusive in approximately 50% of cases. Although negative genetic testing may be secondary to pathogenic mutations within undiscovered genes, an alternative explanation may be the presence of large deletions or duplications involving known genes. These large copy number variants may not be detected with standard clinical genetic testing which is presently limited to direct DNA sequencing. We describe two cases of ARVC possessing large deletions involving plakophilin‐2 (PKP2) identified with microarray analysis and/or multiplex ligation‐dependent probe amplification (MLPA) that would have been classified as genotype negative with standard clinical genetic testing. A deletion of the entire coding region of PKP2 excluding exon 1 was identified in patient 1 and his son. In patient 2, MLPA analysis of PKP2 revealed deletion of the entire gene with subsequent microarray analysis demonstrating a de novo 7.9 Mb deletion of chromosome 12p12.1p11.1. These findings support screening for large copy number variants in clinically suspected ARVC cases without clear disease causing mutations following initial sequencing analysis.  相似文献   
88.
Anatomical Science International - Foramina transversaria are bilateral landmarks of human cervical vertebrae. Morphometric analysis of foramina transversaria is valuable in both clinical and...  相似文献   
89.
BackgroundMultimorbidity of intestinal cancer (IC), type 2 diabetes (T2D) and obesity is a complex set of diseases, affected by environmental and genetic risk factors. High‐fat diet (HFD) and oral bacterial infection play important roles in the etiology of these diseases through inflammation and various biological mechanisms.MethodsTo study the complexity of this multimorbidity, we used the collaborative cross (CC) mouse genetics reference population. We aimed to study the multimorbidity of IC, T2D, and obesity using CC lines, measuring their responses to HFD and oral bacterial infection. The study used 63 mice of both sexes generated from two CC lines (IL557 and IL711). For 12 weeks, experimental mice were maintained on specific dietary regimes combined with co‐infection with oral bacteria Porphyromonas gingivalis and Fusobacterium nucleatum, while control groups were not infected. Body weight (BW) and results of a intraperitoneal glucose tolerance test (IPGTT) were recorded at the end of 12 weeks, after which length and size of the intestines were assessed for polyp counts.ResultsPolyp counts ranged between 2 and 10 per CC line. The combination of HFD and infection significantly reduced (P < .01) the colon polyp size of IL557 females to 2.5 cm2, compared to the other groups. Comparing BW gain, IL557 males on HFD gained 18 g, while the females gained 10 g under the same conditions and showed the highest area under curve (AUC) values of 40 000‐45 000 (min mg/dL) in the IPGTT.ConclusionThe results show that mice from different genetic backgrounds respond differently to a high fat diet and oral infection in terms of polyp development and glucose tolerance, and this effect is gender related.  相似文献   
90.
The merits of surgical treatment of fractures of the mandibular condyle versus non-surgical management remains highly controversial, despite a large volume of literature dedicated to this topic. One reason the controversy remains, is because most of the outcomes in the literature are not directly comparable. The disparate range of condylar fracture classifications used is one of the reasons that studies are not comparable. We sought to review classification systems for condylar fractures used in the recent scientific literature.Review of the literature from 2016 to 2019, looking for papers relating to fractures of the mandibular condyle. Papers identified were assessed for type of study, focus of study, classification system used.88 studies were identified, including prospective and retrospective cohort studies, randomised and non-randomised prospective studies, randomised controlled trials and case series. More studies focussed on epidemiological factors than surgical access, fixation or outcomes. 31 used no classification system, whilst 17 used unique classification systems and 40 used previously referenced classification systems.Classification systems are used to help separate clinical problems into distinguishable groups, where there is a difference in management or outcome depending on the distinguishing features.There is currently a wide diversity of classification systems used for condyle fractures, and as a result, comparisons of surgical access, fixation and outcomes are difficult to make. Having a single classification system across the published literature would allow easier comparison and the classification proposed by the AO group is recommended for future use.  相似文献   
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