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71.
The aim of this study was to assess the frequency and genotypic diversity of carbapenemase-producing Enterobacteriaceae (CPE) in stool samples from patients attending a military hospital in Pakistan. Further aims included the identification of factors that might predispose to faecal carriage and evaluation of 2 chromogenic culture media: Brilliance CRE and chromID CARBA. Of 175 patients, 32 (18.3%) had faecal carriage of CPE and all produced NDM-1 carbapenemase. All of these 32 patients were detected using chromID CARBA compared with 20 patients (62.5%) detected using Brilliance CRE (P = 0.0015). Duration of hospitalization and treatment with co-amoxyclav were statistically associated with a higher likelihood of carriage of CPE (P ≤ 0.05). The majority of NDM-1–producing Enterobacteriaceae co-produced CTX-M-1 group extended spectrum β-lactamase, and one third produced armA-type methylase. NDM-1 carbapenemase was most commonly found amongst commensal types of Escherichia coli, especially phylogenetic group B1.  相似文献   
72.
Background Glutamine (Gln) is an abundant nutrient used by cancer cells. Breast cancers cells and particularly triple-receptor negative breast cancer (TNBC) are reported to be dependent on Gln to produce the energy required for survival and proliferation. Despite intense research on the role of the intracellular Gln pathway, few reports have focussed on Gln transporters in breast cancer and TNBC.Methods The role and localisation of the Gln transporter SLC38A2/SNAT2 in response to Gln deprivation or pharmacological stresses was examined in a panel of breast cancer cell lines. Subsequently, the effect of SLC38A2 knockdown in Gln-sensitive cell lines was analysed. The prognostic value of SLC38A2 in a cohort of breast cancer was determined by immunohistochemistry.Results SLC38A2 was identified as a strongly expressed amino acid transporter in six breast cancer cell lines. We confirmed an autophagic route of degradation for SLC38A2. SLC38A2 knockdown decreased Gln consumption, inhibited cell growth, induced autophagy and led to ROS production in a subgroup of Gln-sensitive cell lines. High expression of SLC38A2 protein was associated with poor breast cancer specific survival in a large cohort of patients (p = 0.004), particularly in TNBC (p = 0.02).Conclusions These results position SLC38A2 as a selective target for inhibiting growth of Gln-dependent breast cancer cell lines.Subject terms: Breast cancer, Cancer metabolism  相似文献   
73.
We present the case of a 52-year-old man, with a history of malignant melanoma, who presented with a testicular lump. Radical orchidectomy confirmed a metastatic malignant melanoma. We discuss salient features of this disease in the light of the published literature.  相似文献   
74.
Health care professionals need to approach their profession with a view to life long learning. They need to develop a strategy to meet their learning needs in a reflective and effective manner. Continuous medical educational (CME) is the traditional tool for learning and updating knowledge. Most of them are in the forms of courses, conferences, journal clubs and workshops. They are mostly didactic sessions and evidence suggests that they are not effective to improve the clinical skills and attitude. Systematic review of teaching evidence-based medicine shows that interactive and clinically integrated learning is the most effective form of learning. It enhances knowledge and skills. Professionals should view CME in a holistic manner in the context of continuous professional development (CPD) and even in the wider concept of knowledge translation, which encompasses both CME and CPD. e Learning is one of the most important forms of non-traditional CME. It provides an efficient and increasingly interactive delivery system that can handle complex and layered information. More work needs to be done to see its effectiveness for practising clinicians.  相似文献   
75.
A forecast of psychiatric bed needs in 1985 for a geographically defined area of north London was attempted. The forecast was made by projection of the results of a longitudinal study (the rundown of two cohorts) and of a cross-sectional study (the annual census of patients in psychiatric beds in 5 consecutive years). The estimate for 1985 was just short of 1 bed per 1000 of population.  相似文献   
76.
Otten TR  Stein PD  Patel KC  Mustafa S  Silbergleit A 《Chest》2003,123(3):809-812
PURPOSE: To evaluate the frequency of diagnosis and the characteristics of brachiocephalic vein and superior vena cava (SVC) thromboembolic disease. BACKGROUND: Thromboembolic disease of the brachiocephalic veins or SVC rarely has been reported. In view of the frequent use of central venous access lines, it would seem that the percentage of hospitalized patients with thromboembolic disease of the brachiocephalic veins or SVC should be higher than is generally recognized. METHODS: A retrospective search for thromboembolic disease involving the brachiocephalic veins and SVC was made of patients who were hospitalized over a 2-year period. RESULTS: Thromboembolic disease of the brachiocephalic veins or SVC was diagnosed in 23 of 34,567 hospitalized adults (0.06%) who were > or = 20 years old. Two of 23 patients (8.7%) had pulmonary embolism. Cancer was present in 17 of 23 patients (74%), and 15 of 23 patients (65%) had central venous access lines. Edema of the arm, face, or neck was present in 21 of 23 patients (91%). Pain or discomfort was present 15 of 23 patients (65%). CONCLUSION: Isolated brachiocephalic vein and SVC thrombosis occur in a sufficient number of hospitalized patients to merit consideration of the diagnosis in patients who have cancer, central venous access lines, or both. The signs and symptoms of brachiocephalic vein thrombosis have features in common with SVC syndrome as well as with upper extremity deep venous thrombosis. In a patient with appropriate clinical findings, venography or other imaging may be indicated.  相似文献   
77.
Valproic acid has been previously associated with hematologic toxicity, including a reversible myelodysplasia-like syndrome without chromosomal abnormalities. We now report three cases of acute leukemia with features of secondary leukemia associated with valproic acid therapy: two cases of acute myelogenous leukemia with multilineage dysplasia, one with trisomy 8 and one with monosomy 7, and one case of secondary acute lymphoblastic leukemia with del (7) (q22q34), del (9) (q21.11q22), del (11) (q12q23). One patient had a previous myelodysplastic syndrome while on valproic acid. Valproic acid has been previously shown to be a histone deacetylase inhibitor. Inhibition of histone deacetylase causes a relaxation of chromatin structure and thus increases susceptibility to DNA damage and sensitizes cells to radiation. We propose that valproic acid therapy may lead to secondary leukemia by increasing DNA damage through chronic inhibition of histone deacetylase.  相似文献   
78.
Acute left main coronary artery occlusion is a catastrophic and mostly fatal event. Patients may present with sudden death or cardiogenic shock. Intra-aortic balloon pump support and emergency revascularization is indicated to preserve the left ventricular function. We describe a case of left main thrombus in a health 24-year-old young male with no risk factors for coronary atherosclerosis.  相似文献   
79.
BACKGROUND: Numerous studies have shown a relationship between hyperhomocysteinemia, atherothrombosis and cardiovascular mortality. However, an association between hyperhomocysteinemia and the extent of coronary artery disease (CAD) remains controversial whereas its relationship with left ventricular systolic function has not been established. METHODS: One hundred and fifty-seven patients with angiographically defined CAD were included. The relationships between hyperhomocysteinemia, severity of CAD and left ventricular systolic function were studied. Left ventricular systolic function was determined primarily by ventriculography. The severity of CAD was determined through coronary angiography using the Gensini score and the number of vessels with > or = 50% stenosis. RESULTS: The mean fasting plasma homocysteine level was 13.4 mumol/l+/-0.5 SE. Elevated levels of homocysteine correlated significantly with increased severity of CAD both by the Gensini scores (r-value = 0.344, P < 0.0005) and the total number of diseased vessels (r-value = 0.387, P < 0.0005). The patients with hyperhomocysteinemia were found to have significantly reduced left ventricular ejection fraction (r-value = -0.382, P < 0.0005). A multivariate regression analysis revealed homocysteine level to be an independent predictor of left ventricular systolic function. In addition, adjusted analysis revealed hyperhomocysteinemia to be associated with global left ventricular dysfunction. CONCLUSION: In patients with CAD, homocysteine levels correlate independently with left ventricular systolic function. The mechanism of this association between homocysteine and left ventricular systolic function is unknown but may be due to a direct effect of homocysteine on myocardial function separate from its effects on coronary atherosclerosis.  相似文献   
80.

Background

Dendritic cells (DCs) promote pathogen recognition, uptake and presentation of antigen through DC-specific intercellular adhesion molecule 3-grabbing non-integrin (DC-SIGN) and toll-like receptors (TLRs).

Aims and Objectives

We aimed to study temporal changes in DCs, TLRs and DC-SIGN during acute viral hepatitis B (AVHB) infection and compare them to chronic (CHB) and to investigate the earliest time point of activated pathogen recognition receptors in hepatitis B viral infection.

Methods

We measured the frequencies of circulating myeloid (mDC) and plasmacytoid (pDC) dendritic cells and IFN-α production along with the expression of DC-SIGN and Toll Like Receptors (TLR's) in HBV patients at different time points. Also investigated in healthy volunteers, the dynamic changes in TLRs expression after receiving hepatitis B vaccine.

Results

On follow-up of AVHB patients, we found the mDC population was significantly higher at week 4 and 6 (p < 0.02, 0.01), whereas the pDC population was unchanged at week 6 compared with week 0. Whereas frequencies of mDCs and pDCs were found to be elevated in AVHB and CHB patients than HC (p < 0.00 and 0.01, respectively) but was comparable among AVHB vs CHB. The DCs in CHB patients were functionally impaired with significantly low IFN-α production and low DCSIGN expression (p < 0.04 and 0.00, respectively). Even after stimulation by TLR agonists, no change was found in IFN-α production in CHB patients. MyD88 and IL-6, IFN-α mRNA levels were also found down-regulated. Interestingly, on follow-up after HBV vaccine, TLRs expression was found high at day 3 after vaccination.

Discussion

The initial events of immune activation might be responsible for modulating immune response. These novel observations would pave the way for the development of antiviral strategies for chronic HBV infection.
  相似文献   
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