Clinical significance of VEGF-A, -C and -D expression in esophageal malignancies

Vascular endothelial growth factors ( VEGF)- A, - C and - D are members of the proangiogenic VEGF family of glycoproteins. VEGF-A is known to be the most important angiogenic factor under physiological and pathological conditions, while VEGF-C and VEGF-D are implicated in the development and sprouting of lymphatic vessels, so called lymphangiogenesis. Local tumor progression, lymph node metastases and hematogenous tumor spread are important prognostic factors for esophageal carcinoma ( EC), one of the most lethal malignancies throughout the world. We found solid evidence in the literature that VEGF expression contributes to tumor angiogenesis, tumor progression and lymph node metastasis in esophageal squamous cell carcinoma ( SCC), and many authors could show a prognostic value for VEGF-assessment. In adenocarcinoma (AC) of the esophagus angiogenic properties are acquired in early stages, particularly in precancerous lesions like Barrett's dysplasia. However, VEGF expression fails to give prognostic information in AC of the esophagus. VEGF-C and VEGF-D were detected in SCC and dysplastic lesions, but not in normal mucosa of the esophagus. VEGF-C expression might be associated with lymphatic tumor invasion, lymph node metastases and advanced disease in esophageal SCC and AC. Therapeutic interference with VEGF signaling may prove to be a promising way of anti-angiogenic co-treatment in esophageal carcinoma. However, concrete clinical data are still pending

Hedgehog signal activation in oesophageal cancer patients undergoing neoadjuvant chemoradiotherapy

The zinc finger protein glioma-associated oncogene homologue 1 (Gli-1) is a critical component of the Hedgehog (Hh) signalling pathway, which is essential for morphogenesis and stem-cell renewal, and is dysregulated in many cancer types. As data were not available on the role of Gli-1 expression in oesophageal cancer progression, we analysed whether it could be used to predict disease progression and prognosis in oesophageal cancer patients undergoing neoadjuvant chemoradiotherapy (CRT). Among 69 patients with histologically confirmed oesophageal squamous cell carcinomas (ESCCs), 25 showed a pathological complete response after preoperative CRT. Overall survival (OS) was significantly associated with lymph-node metastasis, distant metastasis, and CRT, and was further correlated with the absence of both Gli-1 nuclear expression and residual tumour. All patients with Gli-1 nuclear expression (10.1%) had distant or lymph-node metastasis, and six out of seven died within 13 months. Furthermore, patients with Gli-1 nuclear-positive cancers showed significantly poorer prognoses than those without (disease-free survival: mean DFS time 250 vs 1738 months, 2-year DFS 0 vs 54.9%, P=0.009; OS: mean OS time 386 vs 1742 months, 2-year OS 16.7 vs 54.9%, P=0.001). Our study provides the first evidence that Gli-1 nuclear expression is a strong and independent predictor of early relapse and poor prognosis in ESCC after CRT. These findings suggest that Hh signal activation might promote cancer regrowth and progression after CRT

Agricultural, socioeconomic and environmental variables as risks for human verotoxigenic Escherichia coli (VTEC) infection in Finland

<p>Abstract</p> <p>Background</p> <p>Verotoxigenic <it>E. coli </it>(VTEC) is the cause of severe gastrointestinal infection especially among infants. Between 10 and 20 cases are reported annually to the National Infectious Disease Register (NIDR) in Finland. The aim of this study was to identify explanatory variables for VTEC infections reported to the NIDR in Finland between 1997 and 2006. We applied a hurdle model, applicable for a dataset with an excess of zeros.</p> <p>Methods</p> <p>We enrolled 131 domestically acquired primary cases of VTEC between 1997 and 2006 from routine surveillance data. The isolated strains were characterized by virulence type, serogroup, phage type and pulsed-field gel electrophoresis. By applying a two-part Bayesian hurdle model to infectious disease surveillance data, we were able to create a model in which the covariates were associated with the probability for occurrence of the cases in the logistic regression part and the magnitude of covariate changes in the Poisson regression part if cases do occur. The model also included spatial correlations between neighbouring municipalities.</p> <p>Results</p> <p>The average annual incidence rate was 4.8 cases per million inhabitants based on the cases as reported to the NIDR. Of the 131 cases, 74 VTEC O157 and 58 non-O157 strains were isolated (one person had dual infections). The number of bulls per human population and the proportion of the population with a higher education were associated with an increased occurrence and incidence of human VTEC infections in 70 (17%) of 416 of Finnish municipalities. In addition, the proportion of fresh water per area, the proportion of cultivated land per area and the proportion of low income households with children were associated with increased incidence of VTEC infections.</p> <p>Conclusions</p> <p>With hurdle models we were able to distinguish between risk factors for the occurrence of the disease and the incidence of the disease for data characterised by an excess of zeros. The density of bulls and the proportion of the population with higher education were significant both for occurrence and incidence, while the proportion of fresh water, cultivated land, and the proportion of low income households with children were significant for the incidence of the disease.</p

Clinical effectiveness of rapid tests for methicillin resistant Staphylococcus aureus (MRSA) in hospitalized patients: a systematic review

<p>Abstract</p> <p>Background</p> <p>Methicillin resistant <it>Staphylococcus aureus </it>(MRSA) are often resistant to multiple classes of antibiotics. The research objectives of this systematic review were to evaluate the clinical effectiveness of polymerase chain reaction (PCR) versus chromogenic agar for MRSA screening, and PCR versus no screening for several clinical outcomes, including MRSA colonization and infection rates.</p> <p>Methods</p> <p>An electronic literature search was conducted on studies evaluating polymerase chain reaction techniques and methicillin (also spelled meticillin) resistant <it>Staphylococcus aureus </it>that were published from 1993 onwards using Medline, Medline In-Process & Other Non-Indexed Citations, BIOSIS Previews, and EMBASE. Due to the presence of heterogeneity in the selected studies, the clinical findings of individual studies were described.</p> <p>Results</p> <p>Nine studies that compared screening for MRSA using PCR versus screening using chromogenic agar in a hospital setting, and two studies that compared screening using PCR with no or targeted screening were identified. Some studies found lower MRSA colonization and acquisition, infection, and transmission rates in screening with PCR versus screening with chromogenic agar, and the turnaround time for screening test results was lower for PCR. One study reported a lower number of unnecessary isolation days with screening using PCR versus screening with chromogenic agar, but the proportion of patients isolated was similar between both groups. The turnaround time for test results and number of isolation days were lower for PCR versus chromogenic agar for MRSA screening.</p> <p>Conclusions</p> <p>The use of PCR for MRSA screening demonstrated a lower turnaround time and number of isolation days compared with chromogenic agar. Given the mixed quality and number of studies (11 studies), gaps remain in the published literature and the evidence remains insufficient. In addition to screening, factors such as the number of contacts between healthcare workers and patients, number of patients attended by one healthcare worker per day, probability of colonization among healthcare workers, and MRSA status of hospital shared equipment and hospital environment must be considered to control the transmission of MRSA in a hospital setting.</p

MRSA prevalence in european healthcare settings: a review

<p>Abstract</p> <p>Background</p> <p>During the past two decades, methicillin-resistant <it>Staphylococcus aureus </it>(MRSA) has become increasingly common as a source of nosocomial infections. Most studies of MRSA surveillance were performed during outbreaks, so that results are not applicable to settings in which MRSA is endemic. This paper gives an overview of MRSA prevalence in hospitals and other healthcare institutions in non-outbreak situations in Western Europe.</p> <p>Methods</p> <p>A keyword search was conducted in the Medline database (2000 through June 2010). Titles and abstracts were screened to identify studies on MRSA prevalence in patients in non-outbreak situations in European healthcare facilities. Each study was assessed using seven quality criteria (outcome definition, time unit, target population, participants, observer bias, screening procedure, swabbing sites) and categorized as 'good', 'fair', or 'poor'.</p> <p>Results</p> <p>31 observational studies were included in the review. Four of the studies were of good quality. Surveillance screening of MRSA was performed in long-term care (11 studies) and acute care (20 studies). Prevalence rates varied over a wide range, from less than 1% to greater than 20%. Prevalence in the acute care and long-term care settings was comparable. The prevalence of MRSA was expressed in various ways - the percentage of MRSA among patients (range between 1% and 24%), the percentage of MRSA among <it>S. aureus </it>isolates (range between 5% and 54%), and as the prevalence density (range between 0.4 and 4 MRSA cases per 1,000 patient days). The screening policy differed with respect to time points (on admission or during hospital stay), selection criteria (all admissions or patients at high risk for MRSA) and anatomical sampling sites.</p> <p>Conclusions</p> <p>This review underlines the methodological differences between studies of MRSA surveillance. For comparisons between different healthcare settings, surveillance methods and outcome calculations should be standardized.</p

Intestinal parasitosis and shigellosis among diarrheal patients in Gondar teaching hospital, northwest Ethiopia

<p>Abstract</p> <p>Background</p> <p>Diarrheal diseases are the major causes of morbidity and mortality in developing world. Understanding the etiologic agents of diarrheal diseases and their association with socio-demographic characteristics of patients would help to design better preventive measures. Thus, this study was aimed to determine the prevalence of intestinal parasites and enteropathogenic bacteria in diarrheic patients.</p> <p>Methods</p> <p>A cross-sectional study involving 384 consecutive diarrheal patients who visited Gondar teaching hospital, Gondar, Ethiopia from October 2006 to March 2007 was conducted. Stool specimens were collected and examined for intestinal parasites and enteropathogenic bacteria following standard parasitological and microbiological procedures.</p> <p><b><it>Results</it></b></p> <p>Intestinal parasites were diagnosed in 36.5% of the patients. The most frequently encountered protozoan parasite was <it>Entamoeba histolytica/dispar </it>(7.3%) followed by <it>Giardia lamblia </it>(5.0%), C<it>ryptosporidium parvum </it>(1.8%) and <it>Isospora belli </it>(1.3%). The dominant helminthic parasite identified was <it>Ascaris lumbricoides </it>(5.5%) followed by <it>Strongyloides stercoralis </it>and <it>Schistosoma mansoni </it>(3.1% each), hookworm infection (1.8%), and <it>Hymenolepis </it>species (1.3%). Multiple infections of intestinal parasites were also observed in 6.3% of the patients. Among the enteropathogenic bacteria <it>Shigella </it>and <it>Salmonella </it>species were isolated from 15.6% and 1.6%, respectively, of the patients. <it>Escherichia coli O57:H7 </it>was not found in any of the stool samples tested. Eighty eight percent and 83.3% of the <it>Shigella </it>and <it>Salmonella </it>isolates were resistant to one or more commonly used antibiotics, respectively.</p> <p>Intestinal parasitosis was higher in patients who live in rural area, in patients who were washing their hands after visiting toilet either irregularly with soap and without soap or not at all, in patients who used well and spring water for household consumption, and in patients who had nausea (<it>P </it>< 0.05). Statistically significant associations were also observed between Shigella infections and patients who were using well and spring water for household consumption, and patients who had dysentery and mucoid stool (<it>P </it>< 0.05).</p> <p>Conclusions</p> <p>The high prevalence of intestinal parasites and <it>Shigella </it>species in diarrheic patients calls for institution of appropriate public health intervention measures to reduce morbidity and mortality associated with these diseases. The rational use of antibiotics should also be practiced.</p

Clostridium difficile isolates with increased sporulation: emergence of PCR ribotype 002 in Hong Kong

We identified a predominant clone of Clostridium difficile PCR ribotype 002, which was associated with an increased sporulation frequency. In 2009, 3,528 stool samples from 2,440 patients were tested for toxigenic C. difficile in a healthcare region in Hong Kong. A total of 345 toxigenic strains from 307 (13.3%) patients were found. Ribotype 002 was the predominant ribotype, which constituted 35 samples from 29 (9.4%) patients. The mean sporulation frequency of ribotype 002 was 20.2%, which was significantly higher than that of the 56 randomly selected ribotypes other than 002 as concurrent controls (3.7%, p < 0.001). Patients carrying toxigenic ribotype 002 were more frequently admitted from an elderly home (p = 0.01) and received more β-lactam antibiotics in the preceding 3 months compared with the controls (p = 0.04) . The identification of toxigenic ribotype 002 in 2009 was temporally related to a significant increase in both the incidence of toxigenic C. difficile from 0.53 to 0.95 per 1,000 admissions (p < 0.001) and the rate of positive detection from 4.17% to 6.28% (p < 0.001) between period 1 (2004–2008) and period 2 (2009). This finding should alert both the physician and the infection control team to the establishment of and possible outbreaks by ribotype 002 in our hospitals, as in the case of ribotype 027