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Pancreatic cancer screening has been hampered by the high rate of complications associated with interrogating the pancreas. The closest non-invasively accessible mucosa available for pancreatic cancer screening is the periampullary duodenal tissue. Our earlier report has shown the potential of using optical markers to interrogate this tissue for the presence of pancreatic cancer. In this study, we report a larger data set of low-coherence enhanced backscattering (LEBS) and elastic light scattering fingerprinting (ELF) optical markers from the periampullary duodenal mucosa. Optical measurements from biopsy samples were acquired from a total of 203 patients with varying clinical classification including healthy controls, a family history of pancreatic cancer, pancreatitis, mucinous cystic precursor lesions, pancreatic cancer, and other pancreatic malignancies. Evaluation of the performance of an independent testing set for discriminating healthy control patients from pancreatic cancer patients showed a 95% sensitivity, 71% specificity, and 85% area under the receiver operator characteristic (AUROC) curve. Importantly, this performance was uncompromised for detecting potentially curable stages of the disease. Additionally, optical markers in higher risk populations such as family history and pancreatitis had values between those of healthy control and pancreatic cancer patients, thus allowing for future investigations of screening from these high risk groups.  相似文献   
3.
In a group of 35 patients with relapsed and/or chemo-resistant non-Hodgkin's lymphoma (NHL), low-dose total body irradiation (LTBI) (+involved-field radiotherapy to bulky sites) achieved a complete remission rate of 29%, 2-years progression-free survival of 32% and a median progression-free survival of 12 months. The 2-year survival was 42% and the median survival was 17 months. Immuno-staining and flow cytometry of peripheral blood in 14 patients showed that LTBI leads to a significant increase in the percentage of CD4+ cells with a consequent significant increase in the CD4+/CD8+ ratio. High lymphocytic percent and a high percentage of CD4+ cells before LTBI were significantly correlated with longer response duration and overall survival. These data may suggest that the palliative potential of LTBI should be investigated as an alternative to chemotherapy in NHL patients. The pre-treatment percentage of lymphocytes and CD4+ cells may be used as predictors for response to LTBI.  相似文献   
4.
Helicobacter pylori (H. pylori) are pathogenic bacteria that infect a half of the human population, colonize gastric mucosa and can be found in gastric juice. Reflux of gastric juice has been suggested to be associated with glue ear in children. It has been suggested that tonsil and adenoid tissues are potential reservoirs of H. pylori infection. These observations raise the question as to whether H. pylori infection might have a role in otitis media with effusion (OME) in children. The objectives of this research were to evaluate the incidence and possible role of H. pylori in the pathogenesis of OME in children and to evaluate the clarithromycin-resistant strains. Molecular assessment was done to evaluate the culture results vs. molecular study. A total of 60 children, who were prone to ventilation tube insertion, adenoidectomy and/or tonsillectomy were included in the study. The control group consisted of 40 children who underwent adenoidectomy and/or tonsillectomy without the history of OME. Samples of the middle ear fluid and mucosa, adenoid tissue, tonsillar tissue and gastric lavage were cultured and underwent polymerase chain reaction (PCR) analysis then were assembled by using QIAxcel System as capillary electrophoresis for H. pylori detection. There was significant difference between the results of cultures and PCR (P < 0.05). Middle ear fluid culture was positive for H. pylori in 40% of the patients vs. 56.7% PCR results while middle ear mucosa culture was positive in 20% vs. 26.7% PCR results. Gastric lavage culture was positive in 46.6% of the patients and PCR was positive in 63.3% of the patients. Adenoid culture and PCR were positive in 56.3% for each, while tonsil culture was positive in 70% and PCR was positive in 90%. H. pylori presence in the gastric lavage, the tonsillar and adenoid tissues by culture and PCR was significantly more frequent in the study group compared to the control group. The minimum inhibitory concentration (MIC) values of clarithromycin-resistant isolates ranged from 1.5 to 8 μg/ml. This study showed the presence of H. pylori in around 50% of the patients with OME. PCR revealed its sensitivity than culture techniques. The incidence of clarithromycin resistance was found to be high among the isolates (39.6%).  相似文献   
5.
The clinical significance of detecting minimal residual disease (MRD) in B-lineage acute lymphoblastic leukaemia (ALL) was evaluated by quantitative flow cytometry using a combination of TdT with CD10 and CD19. 53 patients with B-cell precursor ALL were followed during and after completion of treatment (median follow-up 23 months). Nine patients relapsed and MRD had been detected in six of them, 5–15 weeks before relapse despite morphological complete remission. 43 patients remain in clinical remission and in none of these was MRD detected. Disease-free survival based on the detection of MRD by flow cytometry showed a statistically significant difference between both groups ( P  < 0.0001). The absence of MRD correlates with a low relapse rate, whereas the presence of MRD predicted early relapse. This study has shown that flow cytometry can improve the morphologic assessment of bone marrow (BM) remission status in B-lineage ALL. The finding of < 5% blasts in BM aspirates did not correlate with 'true' remission in a proportion of cases as residual leukaemic blasts were detected by flow cytometry in nine samples from six patients. On the other hand, the presence of > 5% blasts assessed by morphology was not necessarily a feature of relapse in five patients as these cells were shown to have a phenotype identical to normal TdT-negative B-cell precursors. Quantitative flow cytometry was more informative than conventional morphology to assess remission status and showed a strong correlation with clinical outcome. This methodology is useful to define MRD in the majority of patients with B-lineage ALL and should be tested in prospective clinical trials.  相似文献   
6.
Hematogones are benign immature B cells that commonly populate the bone marrow of children. Their presence has been noted to interfere with the flow-cytometric analysis of acute lymphoblastic leukemia (ALL), because their immunophenotype is similar to B-precursor cell lymphoblasts. Immune-mediated thrombocytopenia is a clinical condition characterized by increased platelet destruction due to sensitization of platelets by autoantibodies. The aim of this study was to determine the incidence and clinical impact of bone marrow hematogones in cases of acute immune thrombocytopenic purpura (ITP) among children. This was done by immunophenotyping of bone marrow lymphocytes of ITP cases and controls and follow up of cases. This study was done on 25 cases of ITP, 12 females and 13 males, their age ranged from 2 to 13 years. A control group was included in the study, 15 cases of apparently healthy children with matching age and sex taken from among bone marrow donors. Cases and controls were subjected to bone marrow lymphocyte immunophenotyping with flow-cytometry to verify the presence of hematogones. A statistically significant increase in the percentage of hematogones was demonstrated in their bone marrows. An increased percentage of CD10+ lymphocytes was demonstrated; with a mean of 18+/-15.2%, CD19+ with a mean of 27+/-16.3% and CD34+ with a mean of 3.7+/-3.2%. No correlation was found between the percentage of hematogones and peripheral platelet count or bone marrow lymphocytic count. In conclusion, there is an increase in the bone marrow hematogones in ITP cases in comparison to normal controls. This could be the sequence of an immunological response to the cause which determined the disease, or the regeneration of the stem cell compartment following transient damage.  相似文献   
7.
The immune system can effectively eliminate hepatitis C virus (HCV) in 15 % of acute hepatitis cases. It is assumed that certain HLA-DR alleles present HCV epitopes more effectively to CD4 helper T cells than do others resulting in vigorous proliferative response to these epitopes and probably HCV recovery. So, we aimed at investigating the frequency of HLA-DRB1*0101 and DRB1*0301 alleles in child and adult haemophilics and in HCV positive hepatocellular carcinoma (HCC) patients in a trial to predict patients who require early therapeutic intervention. We also evaluated interleukin (IL)-12 levels in these patients since IL-12 induces interferon (IFN)-gamma production. This study was conducted on 50 antiHIV negative male patients subdivided into: 25 HCV negative haemophilics (group I), 10 HCV positive haemophilics (group II) and 15 HCV positive HCC (group III). Fifteen healthy persons of matched age and free of HCV and HIV infections were chosen as controls (group IV). All patients and controls were subjected to thorough history taking and clinical examination, routine and diagnostic investigations, viral markers, DRB1*0101 and DRB1*0301 amplification by polymerase chain reaction and plasma IL-12 quantitation by enzyme linked immunosorbent assay (ELISA). The frequencies of DRB1*0101 and DRB1*0301 were 20% and 30% respectively in HCV positive haemophilics and 13.3% and 40%, respectively in HCC. IL-12 levels were significantly lower in HCC cases than in HCV positive haemophilics. Among the haemophilics, IL-12 levels were non-significantly higher in children than in adults and were associated with the given number of blood product bags. DRB1*0101 and DRB1*0301 may have a role in HCV clearance and persistence in Egyptian patients with haemophilia and HCC. Low IL-12 levels encountered in HCV positive haemophilics suggest its relation to immunopathogenesis and outcome of HCV infection.  相似文献   
8.
Women of childbearing age are particularly vulnerable to the adverse effects of elevated blood pressure (BP), with dietary and lifestyle habits being increasingly recognized as important modifiable environmental risk factors for this condition. Using data from the National STEPwise survey conducted in Qatar in year 2012, we aimed to examine lifestyle patterns and their association with elevated BP among Qatari women of childbearing age (18–45 years). Socio-demographic, lifestyle, dietary, anthropometric and BP data were used (n = 747). Principal component factor analysis was applied to identify the patterns using the frequency of consumption of 13 foods/food groups, physical activity level, and smoking status. Multivariate logistic regression analyses were used to evaluate the association of the identified lifestyle patterns with elevated BP and to examine the socio-demographic correlates of these patterns. Three lifestyle patterns were identified: a “healthy” pattern characterized by intake of fruits, natural juices, and vegetables; a “fast food & smoking” pattern characterized by fast foods, sweetened beverages, and sweets, in addition to smoking; and a “traditional sedentary” pattern which consisted of refined grains, dairy products, and meat in addition to low physical activity. The fast food & smoking and the traditional & sedentary patterns were associated with an approximately 2-fold increase in the risk of elevated BP in the study population. The findings of this study highlight the synergistic effect that diet, smoking and physical inactivity may have on the risk of elevated BP among Qatari women.  相似文献   
9.
10.

Background and study aims

Central nervous system (CNS) involvement in hepatitis C virus (HCV) infection has different facets such as anxiety, depression, cognitive impairment and vasculitis. We were interested in detecting subclinical CNS involvement in chronic HCV infected subjects with and without systemic vasculitis.

Patients and methods

Nineteen patients (15 females and 4 males) with chronic HCV infection (mean age 46.5?±?7 and mean duration since diagnosis of HCV infection 4.7?±?4?years, including 6 (32%) Child-Pugh class A cirrhotic patients) and 30 age, sex and education matched healthy control subjects were studied. Thirteen patients had associated vasculitis. Patients and control subjects were assessed using the block design and comprehension subtests of Wechsler Bellevue Adult Intelligence Scale, Wechsler Memory scale (WMS), Beck Anxiety Inventory (BAI) and Beck Depression Inventory (BDI). Brain HMPAO Single Photon Emission Computed Tomography (SPECT) was performed for HCV patients.

Results

Patients with HCV had lower scores on the block design test compared to control subjects (8.37?±?1.89 versus 10.37?±?1.47, p?<?0.001), lower total WMS scores (43.15?±?10.49 versus 60.27?±?8.08, p?<?0.001) and higher anxiety and depression scores (16.94?±?10.46 and 37.17?±?10.38 versus 10.3?±?4.67 and 28.9?±?5.99, p?=?0.004 and 0.001, respectively). Total WMS were lower in HCV patients with vasculitis compared to those without vasculitis (39.14?±?9.3 versus 51.17?±?8.3, p?=?0.019) while the block design and comprehension tests, BAI and BDI were not significantly different between both groups. The block design and comprehension tests, WMS, BAI and BDI were not significantly different between cirrhotic and non-cirrhotic patients. Seven patients had different patterns of cerebral hypoperfusion on SPECT, and all of them had associated vasculitis. Abnormal SPECT was associated with lower total WMS scores (35.87?±?10.8 versus 46.79?±?8.6 in those with normal SPECT, p?=?0.049).

Conclusions

Vasculitis may contribute to the development of neuropsychiatric involvement in HCV patients.  相似文献   
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