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101.
Multilocus sequence typing for characterization of clinical and environmental salmonella strains 总被引:8,自引:0,他引:8 下载免费PDF全文
Kotetishvili M Stine OC Kreger A Morris JG Sulakvelidze A 《Journal of clinical microbiology》2002,40(5):1626-1635
Multilocus sequence typing (MLST) based on the 16S RNA, pduF, glnA, and manB genes was developed for Salmonella, and its discriminatory ability was compared to those of pulsed-field gel electrophoresis (PFGE) and serotyping. PFGE differentiated several strains undifferentiable by serotyping, and 78 distinct PFGE types were identified among 231 Salmonella isolates grouped into 22 serotypes and 12 strains of undetermined serotype. The strains of several PFGE types were further differentiated by MLST, which suggests that the discriminatory ability of MLST for the typing of Salmonella is better than that of serotyping and/or PFGE typing. manB-based sequence typing identified two distinct genetic clusters containing 32 of 54 (59%) clinical isolates whose manB gene sequences were analyzed. The G+C contents and Splitstree analysis of the manB, glnA, and pduF genes of Salmonella indicated that the genes differ in their evolutionary origins and that recombination played a significant role in their evolution. 相似文献
102.
Koppelman GH Stine OC Xu J Howard TD Zheng SL Kauffman HF Bleecker ER Meyers DA Postma DS 《The Journal of allergy and clinical immunology》2002,109(3):498-506
BACKGROUND: Atopy is a phenotype associated with asthma that has a heritable component. However, the role of atopysusceptibility genes in the development and expression of asthma and allergic disorders is not understood. OBJECTIVE: We sought to study the familial aggregation and co-occurrence of atopic phenotypes within family members of patients with asthma and to identify chromosomal regions that may contain genes that regulate different atopic phenotypes. METHODS: In 200 families (n = 1174) ascertained through a proband with asthma, genome-wide screen and linkage analysis was performed for the following atopic phenotypes: (1) specific IgE to common aeroallergens (Phadiatop assay); (2) specific IgE to Der p 1; (3) positive skin test responses to house dust mite; (4) positive skin test responses to 1 or more of 16 allergens; and (5) peripheral blood eosinophils. Results were compared with the linkage results for total serum IgE levels. RESULTS: There was clear familial aggregation of atopy. A high total serum IgE level in combination with a positive Phadiatop result or a normal total IgE level in combination with a negative Phadiatop result was found in 56.1% of the probands and 66.9% of the offspring. Several chromosomal regions that showed evidence for linkage to an atopic phenotype (ie, 2q, 6p, 7q, and 13q) also showed evidence of linkage with total serum IgE (Xu et al. Am J Hum Genet 2000;67:1163-73). Specific regions of interest for atopic traits were also detected on chromosomes 11q, 17q, and 22q. CONCLUSIONS: Atopic phenotypes show familial aggregation, although family members may differ in expression of atopy. Specific chromosomal regions appear to be important in susceptibility to different phenotypes of atopic responsiveness. 相似文献
103.
104.
Janis Kritzinger Marguerite Schneider Leslie Swartz Stine Hellum Braathen 《Patient education and counseling》2014
Objective
To explore whether there are other factors besides communication difficulties that hamper access to health care services for deaf patients.Methods
Qualitative methodology using semi-structured interviews with 16 deaf participants from the National Institute for the Deaf in Worcester and 3 Key informants from the Worcester area, South Africa.Results
Communication difficulties were found to be a prominent barrier in accessing health care services. In addition to this interpersonal factors including lack of independent thought, overprotectedness, non-questioning attitude, and lack of familial communication interact with communication difficulties in a way that further hampers access to health care services.Conclusion
These interpersonal factors play a unique role in how open and accepting health services feel to deaf patients.Practice implications
Health care services need to take cognizance of the fact that providing sign language interpreters in the health care setting will not necessarily make access more equitable for deaf patients, as they have additional barriers besides communication to overcome before successfully accessing health care services. 相似文献105.
Nynke D Scherpbier-de Haan Gerald MM Vervoort Chris van Weel Jozé CC Braspenning Jan Mulder Jack FM Wetzels Wim JC de Grauw 《The British journal of general practice》2013,63(617):e798-e806
Background
Chronic kidney disease (CKD) is highly prevalent in patients with diabetes or hypertension in primary care. A shared care model could improve quality of care in these patientsAim
To assess the effect of a shared care model in managing patients with CKD who also have diabetes or hypertension.Design and setting
A cluster randomised controlled trial in nine general practices in The Netherlands.Method
Five practices were allocated to the shared care model and four practices to usual care for 1 year. Primary outcome was the achievement of blood pressure targets (130/80 mmHg) and lowering of blood pressure in patients with diabetes mellitus or hypertension and an estimated glomerular filtration rate (eGFR)<60ml/min/1.73m2.Results
Data of 90 intervention and 74 control patients could be analysed. Blood pressure in the intervention group decreased with 8.1 (95% CI = 4.8 to 11.3)/1.1 (95% CI = −1.0 to 3.2) compared to −0.2 (95% CI = −3.8 to 3.3)/−0.5 (95% CI = −2.9 to 1.8) in the control group. Use of lipid-lowering drugs, angiotensin-system inhibitors and vitamin D was higher in the intervention group than in the control group (73% versus 51%, 81% versus 64%, and 15% versus 1%, respectively, [P = 0.004, P = 0.01, and P = 0.002]).Conclusion
A shared care model between GP, nurse practitioner and nephrologist is beneficial in reducing systolic blood pressure in patients with CKD in primary care. 相似文献106.
Background
Cirrhosis-related complications are a major cause of morbidity and mortality in areas where its risk factors are endemic.Objective
We determined the prevalence of decompensated cirrhosis among patients on the gastroenterology service of Mulago Hospital and described the clinical and laboratory features of these patients.Methods
All patients admitted to the unit were assessed and their diagnosis documented. Patients with cirrhosis had clinical features of decompensation recorded. History of alcohol consumption was taken and testing for hepatitis B surface antigen (HBsAg) and hepatitis C antibody (anti-HCV) performed.Results
Between September 2010 and January 2011, we enrolled 482 patients. The majority (53.7%) were male, overall median age 38 years. Decompensated cirrhosis was diagnosed in 85 (17.6%) patients. Of the 85 patients, 47 (55.3%) gave a history of alcohol intake, HBsAg was positive in 23 (27.1%) and anti-HCV in 3 (3.5%). Decompensation was defined by ascites among 81 (95.3%) patients, variceal bleeding in 31 (36.5%), encephalopathy in 20 (23.5%).Conclusion
Cirrhosis is common in Mulago hospital presenting mainly with ascites and variceal bleeding. Aside from controlling causes of liver diseases, especially alcohol and hepatitis B virus infection, in the interim it is necessary to manage complications in patients who already have cirrhosis. 相似文献107.
Urania Kotzaeridou Sara K. Young-Baird Vanessa Suckow Alexis G. Thornburg Matias Wagner Inga Harting Stine Christ Tim Strom Thomas E. Dever Vera M. Kalscheuer 《Clinical genetics》2020,98(5):507-514
Rare pathogenic EIF2S3 missense and terminal deletion variants cause the X-linked intellectual disability (ID) syndrome MEHMO, or a milder phenotype including pancreatic dysfunction and hypopituitarism. We present two unrelated male patients who carry novel EIF2S3 pathogenic missense variants (p.(Thr144Ile) and p.(Ile159Leu)) thereby broadening the limited genetic spectrum and underscoring clinically variable expressivity of MEHMO. While the affected male with p.(Thr144Ile) presented with severe motor delay, severe microcephaly, moderate ID, epileptic seizures responsive to treatments, hypogenitalism, central obesity, facial features, and diabetes, the affected male with p.(Ile159Leu) presented with moderate ID, mild motor delay, microcephaly, epileptic seizures resistant to treatment, central obesity, and mild facial features. Both variants are located in the highly conserved guanine nucleotide binding domain of the EIF2S3 encoded eIF2γ subunit of the heterotrimeric translation initiation factor 2 (eIF2) complex. Further, we investigated both variants in a structural model and in yeast. The reduced growth rates and lowered fidelity of translation with increased initiation at non-AUG codons observed for both mutants in these studies strongly support pathogenicity of the variants. 相似文献
108.
The GAP-related domain of tuberin, the product of the TSC2 gene, is a target for missense mutations in tuberous sclerosis 总被引:5,自引:0,他引:5
Maheshwar MM; Cheadle JP; Jones AC; Myring J; Fryer AE; Harris PC; Sampson JR 《Human molecular genetics》1997,6(11):1991-1996
Tuberous sclerosis is an autosomal dominant trait in which the
dysregulation of cellular proliferation and differentiation results in the
development of hamartomatous growths in many organs. The TSC2 gene is one
of two genes determining tuberous sclerosis. Inactivating germline
mutations of TSC2 in patients with tuberous sclerosis and somatic loss of
heterozygosity at the TSC2 locus in the associated hamartomas indicate that
TSC2 functions as a tumour suppressor gene and that loss of function is
critical to expression of the tuberous sclerosis phenotype. The TSC2
product, tuberin, has a region of homology with the GTPase activating
protein rap1GAP and stimulates the GTPase activity of rap1a and rab5a in
vitro. Here we show that the region of homology between tuberin and human
rap1GAP and the murine GAP mSpa1 is more extensive than previously reported
and spans approximately 160 amino acid residues encoded within exons 34-38
of the TSC2 gene. Single strand conformation polymorphism analysis of these
exons in 173 unrelated patients with tuberous sclerosis and direct
sequencing of variant conformers together with study of additional family
members enabled characterisation of disease associated mutations in 14
cases. Missense mutations, which occurred in exons 36, 37 and 38 were
identified in eight cases, four of whom shared the same recurrent change
P1675L. Each of the five different missense mutations identified was shown
to occur de novo in at least one sporadic case of tuberous sclerosis. The
high proportion of missense mutations detected in the region of the TSC2
gene encoding the GAP-related domain supports its key role in the
regulation of cellular growth.
相似文献
109.
Stine Knudsen Poul J. Jennum J?rgen Alving S?ren Paludan Sheikh Steen Gammeltoft 《Sleep》2010,33(2):169-176
Study Objectives:
The International Classification of Sleep Disorders (ICSD-2) criteria for low CSF hypocretin-1 levels (CSF hcrt-1) still need validation as a diagnostic tool for narcolepsy in different populations because inter-assay variability and different definitions of hypocretin deficiency complicate direct comparisons of study results.Design and Participants:
Interviews, polysomnography, multiple sleep latency test, HLA-typing, and CSF hcrt-1 measurements in Danish patients with narcolepsy with cataplexy (NC) and narcolepsy without cataplexy (NwC), CSF hcrt-1 measurements in other hypersomnias, neurological and normal controls. Comparisons of hypocretin deficiency and frequency of HLA-DQB1*0602-positivity in the Danish and eligible NC and NwC populations (included via MEDLINE search), by (re)calculation of studyusing the ICSD-2 criterion for low CSF hcrt-1 (<30% of normal mean).Measurements and Results:
In Danes, low CSF hcrt-1 was present in 40/46 NC, 3/14 NwC and 0/106 controls (P < 0.0001). Thirty-nine of 41 NC and 4/13 NwC patients were HLA-DQB1*0602-positive (P < 0.01). Hypocretin-deficient NC patients had higher frequency of cataplexy, shorter mean sleep latency, more sleep onset REM periods (P < 0.05) and more awakenings (NS) than did NC patients with normal CSF hcrt-1. Across populations, low CSF hcrt-1 and HLA-DQB1*0602-positivity characterized the majority of NC (80% to 100%, P = 0.53; 80% to 100%, P = 0.11) but a minority of NwC patients (11% to 29%, P = 0.75; 29% to 89%, P = 0.043).Conclusion:
The study provides evidence that hypocretin deficiency causes a more severe NC phenotype. The ICSD-2 criterion for low CSF hcrt-1 (<30% of normal mean) is valid for diagnosing NC, but not NwC. HLA-typing should precede CSF hcrt-1 measurements because hypocretin deficiency is rare in HLA-DQB1*0602-negative patients.Citation:
Knudsen S; Jennum PJ; Alving J; Sheikh SP; Gammeltoft S. Validation of the ICSD-2 criteria for CSF hypocretin-1 measurements in the diagnosis of narcolepsy in the Danish population. SLEEP 2010;33(2):169-176. 相似文献110.