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101.
The aim of this work was to specify the timecourse of response to interferon (IFN) of hepatitis Gvirus (HGV) and hepatitis C virus (HCV) in coinfectedindividuals. A group of 33 patients, undergoing 12 months of IFN therapy for chronic hepatitis C,was screened for the presence of both HGV and HCV RNAsto select seven coinfected patients. Spontaneousrecovery from HGV infection was excluded through the detection of antibodies to the envelope-2protein of HGV and HCV isolates were genotyped. Withinthree months of treatment, we found that HGV RNA wastransiently cleared in 6/7 patients, but the rate of long-term favorable response was very low(1/7). In addition, considering the same individualsseparately, it was shown that HGV and HCV responded toIFN with different kinetics in 5/7 patients. Takentogether, these results underscore the importance of thevirological basis of the resistance to IFNtreatment.  相似文献   
102.
OBJECTIVE: To evaluate the reliability of contrast-unenhanced power Doppler (CUPD) and contrast-enhanced power Doppler (CEPD) ultrasound (US) assessment of synovial vascularity of knee joint synovitis by prospective comparison with the "gold standard," arthroscopy. METHODS: A total of 18 knees of 17 patients with refractory rheumatoid and psoriatic knee joint synovitis were examined by US. Recognition of PD synovial vessel flow and its spatial arrangement in relation to the pannus/cartilage interface (P/CI) or fluid/synovium interface (F/SI) were studied by CUPD- and CEPD-US after a single intravenous bolus of galactosel palmitic acid (Levovist). Arthroscopy video recordings were reanalyzed by computer image analysis to assess synovial vascular marking. CUPD and CEPD flow signal scores were compared with each other and with corresponding vascular marking scores. Using villous vascular marking as reference, CUPD and CEPD sensitivity and specificity were measured. Interobserver variability was evaluated. RESULTS: Compared with the unenhanced PD method, contrast administration increased the PD flow signal score in 13/18 knees (72.2%), allowing increased detection of F/SI PD flow signal configuration (p < 0.018) and of the coexistence of P/CI and F/SI PD imaging (p < 0.0078). With arthroscopy as reference, contrast-enhanced PD was found to be more useful than the unenhanced method, showing more reproducible PD signal scores (p = 0.05 vs p = nonsignificant), as well as higher sensitivity (80% vs 30%), but lower specificity (62% vs 87%), in the recognition of increased vascularity of synovial villi. Interobserver agreement was 100%. CONCLUSION: The prospective comparison with arthroscopy showed the reliability of the CEPD method in synovial vessel recognition and its potential clinical usefulness in assessment of knee joint synovitis.  相似文献   
103.
Background, The pathogenesis of non-alcoholic steatohepatitis remains unclear from several points of view. Minimal diagnostic criteria are still not defined. Aim. To gather information useful for diagnosis and to improve the understanding of pathogenic mechanisms.

Patients. A series of 14 patients with non-alcoholic steatohepatitis, identified among liver outpatients, were paired for age, sex and alanine amino transferase values with 14 patients with hepatitis C virus infection without steatosis.

Methods. Clinical, biochemical and immunohistological examination, including characterisation of inflammatory cell population, evaluation of type 111 collagen and tenascin deposition, activation of stellate cells, hepatocellular apoptosis and proliferation.

Results. Patients with non-alcoholic steatohepatitis were more frequently obese, had higher triglyceride concentrations and lower gamma-globulins. T lymphocytes outnumbered polymorphonuclear cells, both in hepatitis C and in steatohepatitis, with a larger number of CD8 lymphocytes in patients with viral hepatitis but a comparable number of granulocytes. This resulted in a higher granulocytes to T cells ratio in steatohepatitis, possibly making these cells more easily detectable in spite of similar absolute numbers. Portal fibrosis and piecemeal necrosis were prevalent in hepatitis C virus infection, pericentral fibrosis was similar. Hepatocellular, apoptosis and proliferation as well as stellate cell activation were less relevant in steatohepatitis than in hepatitis C virus infection in spite of similar alanine amino transferase levels.

Conclusions. These data provide a possible explanation for the relatively low tendency to progression of non-alcoholic steatohepatitis in most patients despite increased alanine amino transferase and suggest that non-death-related release of alanine amino transferase might occur in non-alcoholic steatohepatitis. This makes liver biopsy an essential part of the clinical setting supporting diagnosis, evaluation of severity and possibly definition of the evolutionary trend.  相似文献   

104.
In our study we compared the prognostic significance of clinical variables, laboratory results and different classification models of ventricular ectopic beats recorded by means of a pre-discharge 24 hour ambulatory electrocardiographic monitoring, in 210 survivors of acute myocardial infarction. In addition a full multivariate analysis of the factors affecting survival time was carried out using Cox's proportional hazards (multiple) regression model. Multivariate stepwise discriminant analysis identified hypertension, congestive heart failure assessed by Killip class, and the grading system for ventricular arrhythmias as the most important prognostic variables. When Moss grading system for ventricular arrhythmias was used, the relative risk was a superior as heavy Moss grading system (Moss 2 vs Moss 1 and Moss 3-4 vs Moss 1, relative risk = 1.2 and 3.6 total death, respectively). Furthermore, the hazard ratio of Moss grading system was higher utilizing as comparison patients without ventricular ectopic beats (relative risk = 1.7 for Moss 2 and 5.3 for Moss 3-4) than patients with ventricular ectopic beats less than one/hour (relative risk = 1.2 for Moss 2 and 3.7 for Moss 3-4). Thus, in survivors of acute myocardial infarction, a rational and useful ventricular ectopic beats categorization includes both frequency and the presence or absence of malignant characteristics.  相似文献   
105.
An aneuploid-immune paradox encompasses somatic copy-number alterations (SCNAs), unleashing a cytotoxic response in experimental precancer systems, while conversely being associated with immune suppression and cytotoxic-cell depletion in human tumors, especially head and neck cancer (HNSC). We present evidence from patient samples and cell lines that alterations in chromosome dosage contribute to an immune hot-to-cold switch during human papillomavirus-negative (HPV) head and neck tumorigenesis. Overall SCNA (aneuploidy) level was associated with increased CD3+ and CD8+ T cell microenvironments in precancer (mostly CD3+, linked to trisomy and aneuploidy), but with T cell-deficient tumors. Early lesions with 9p21.3 loss were associated with depletion of cytotoxic T cell infiltration in TP53 mutant tumors; and with aneuploidy were associated with increased NK-cell infiltration. The strongest driver of cytotoxic T cell and Immune Score depletion in oral cancer was 9p-arm level loss, promoting profound decreases of pivotal IFN-γ-related chemokines (e.g., CXCL9) and pathway genes. Chromosome 9p21.3 deletion contributed mainly to cell-intrinsic senescence suppression, but deletion of the entire arm was necessary to diminish levels of cytokine, JAK-STAT, and Hallmark NF-κB pathways. Finally, 9p arm-level loss and JAK2-PD-L1 codeletion (at 9p24) were predictive markers of poor survival in recurrent HPV HNSC after anti–PD-1 therapy; likely amplified by independent aneuploidy-induced immune-cold microenvironments observed here. We hypothesize that 9p21.3 arm-loss expansion and epistatic interactions allow oral precancer cells to acquire properties to overcome a proimmunogenic aneuploid checkpoint, transform and invade. These findings enable distinct HNSC interception and precision-therapeutic approaches, concepts that may apply to other CN-driven neoplastic, immune or aneuploid diseases, and immunotherapies.

The genetic bases for predisposition, and neoplastic transformation, to cancer have been increasingly well described. However, it remains less clear how early, precancer cells employ these genetic alterations to acquire the characteristic features and properties (1) of malignant disease. For example, studies of the immune landscape led to breakthrough trials of programmed death-1 (PD-1) inhibitors for recurrent, metastatic head and neck squamous cell carcinoma (HNSC) therapy (24). This underscores the importance of immune modulation in these tumors, despite a still suboptimal overall response rate of less than 20% in advanced cancers. Immune response within tumors has been observed to be strongest at the earliest neoplastic stages, as reported recently in lung adenocarcinoma precursors (5). As such, new, immune-based strategies could be developed to reduce the high global burden of HNSC, by intercepting the most common precursor of the most common HNSC presentation: HPV oral squamous cell carcinomas (68).Studies of chromosome somatic copy-number (CN) alteration (SCNA) profiles have reported the impact of 3p14, 9p21, or 17p13 loss in molecular models of HNSC progression (9) and risk (1015). Early studies reported that patients with oral precancers harboring 9p21 and/or 3p14 loss were at significantly greater cancer risk than those with retention at these loci (10, 16). A comprehensive, prospective validation study examined the relative contribution of six candidate chromosome-arm regions. 9p21 loss had the greatest influence on cancer risk (13). The mechanism underlying the association between CN and malignant transformation of precancers, however, is unclear (1720). Studies of CN-altered neoplastic cells have shown that SCNAs can trigger a cytotoxic response in experimental precancer systems (21, 22) but, paradoxically, were associated with immune evasion (23) and suppression (24) in computational studies of naturally occurring human cancers. The latter, in melanoma, found that nonresponders to PD-1 and CTLA-4 blockade had higher CN alteration and loss burdens, which correlated with immunologically cold tumors, characterized by cytotoxic-cell, marker, and metric reductions, and suppressive microenvironment cell, network, and signal increases (2326). This SCNA-cold association was particularly strong in our previous, pan-The Cancer Genome Atlas (TCGA) computational study in HNSC (23). These data point to a putative in vivo switch from immune hot-to-cold in the precancer–cancer transition, and raise the hypothesis that SCNAs in precursor lesions contribute to malignant transformation through genomic events and mechanisms that enable the acquisition of immune-suppressive, evasive properties. To test this hypothesis, we evaluated CN influence on immune profiles and outcomes in a large prospective oral precancer patient cohort, and HPV HNSC (tissue specimens and cell lines) and anti–PD-1–treated recurrent-disease cohorts.  相似文献   
106.
The relationship between the hypothalamus-pituitary morphology and the somatotroph responsiveness to maximal provocative tests exploring the GH releasable pool is still unclear. We evaluated the GH-releasing effect of GHRH plus arginine (GHRH plus Arg) in 36 patients with congenital GH deficiency (GHD) according to their pituitary magnetic resonance imaging findings, consisting of anterior pituitary hypoplasia, stalk agenesis (neural and or vascular component), and posterior pituitary ectopia. Seventeen children (12 boys and 5 girls, aged 1--5.2 yr) were evaluated at the time of diagnosis of GHD (mean age, 3.6 +/- 1.4 yr), and 19 adults (13 males and 6 females, aged 15.9-28.6 yr) with childhood-onset GHD were reevaluated after completion of GH treatment (at least 6 months of withdrawal) at a mean age of 20.5 +/- 3.5 yr. Eleven children had isolated GHD, and 6 had multiple pituitary hormone deficiency (MPHD) whereas 7 adults had isolated GHD, and 12 had MPHD. A residual vascular component of the pituitary stalk was visualized in 7 children and 7 adults with isolated GHD, whereas magnetic resonance imaging showed complete pituitary stalk agenesis (both vascular and neural components) in 10 children and 10 adults, including 16 with MPHD (6 children) and 4 children with isolated GHD. In the children, the median peak GH response to GHRH plus Arg (7.6 microg/L; range, 2.4--40.2 microg/L) was significantly higher than that in the adults (1.8 microg/L; range, 0.8--37.4 microg/L; P = 0.0039); it was also significantly higher in the isolated GHD patients (18 microg/L; range, 3.3--40.2 microg/L) than in those with MPHD (1.9 microg/L; range, 0.8--7.6 microg/L; P = 0.00004). In the patients with residual vascular component of the pituitary stalk the median peak GH responses to GHRH plus Arg (19.1 microg/L; range, 1.6--40.2 microg/L) was significantly higher than that in patients with complete pituitary stalk agenesis (2.2 microg/L; range, 0.8--8.8 microg/L; P = 0.00005). There was a trend toward a decrease with age in peak GH response to GHRH plus ARG: Mean serum insulin-like growth factor I (IGF-I) levels were 36 +/- 7.1 microg/L in the children and 63.5 +/- 22.6 microg/L in the adults (P = 0.0001). The mean IGF-I level did not differ between the children with (35.7 +/- 4.8 microg/L) and those without (36.3 +/- 8.7 microg/L) the pituitary stalk; it was much higher in the adults with residual vascular pituitary stalk (81.1 +/- 17.7 microg/L) than in those with complete pituitary stalk agenesis (47.7 +/- 12.5 microg/L; P = 0.0002). The IGF-I level was 36.1 +/- 6.7 microg/L in the isolated GHD children and 36 +/- 8.6 microg/L in those with MPHD; levels were 82.1 +/- 19.4 and 52.7 +/- 16.8 microg/L respectively, in the adults (P = 0.003). In this study we have confirmed that the partial integrity of the hypothalamic pituitary connections is essential for GHRH plus Arg to express its GH-releasing activity and have shown that this provocative test is able to stimulate GH secretion to a greater extent in those patients with GHD, but with a residual vascular component of the pituitary stalk. This test is reliable in the diagnosis of congenital hypopituitarism in both children and adults when associated with complete pituitary stalk agenesis and MPHD. In younger children with congenital GHD but less severe impairment of the pituitary stalk the GH response to GHRH plus Arg may be within the normal range; deterioration of pituitary GH reserve with a GH response of less than 10 microg/L after 20 yr of age makes this test very sensitive in the diagnosis of adult GHD.  相似文献   
107.
OBJECTIVE: Impaired diastolic function and left ventricular hypertrophy can occur early in the natural history of essential hypertension. High circulating levels of endogenous ouabain (EO) have been described in essential hypertension and have also been associated with left ventricular hypertrophy. The aim of this study was to investigate whether these cardiac modifications are related to plasma EO levels in the offspring of hypertensive families. METHODS: The study involved 41 subjects with (FAM+) and 45 subjects without (FAM-) a family history of hypertension. Arterial blood pressure, left ventricular geometry and function, and plasma EO levels were measured in each subject. RESULTS: Plasma EO levels were higher in the FAM+ subjects (221.5 +/- 10.95 versus 179.6 +/- 9.58 pmol/l, P = 0.004), and directly correlated with both systolic (r = 0.417, P < 0.0001) and diastolic blood pressure (r = 0.333, P = 0.002). Plasma EO was inversely related to an index of cardiac diastolic function determined as the ratio between the early and late peak flow velocity (r = -0.286, P = 0.012) and isovolumetric relaxation time (IVRT) (r = 0.32, P = 0.003). The IVRT was also significantly higher in FAM+, correlated with the IVRT (r = 0.32, P = 0.003). The IVRT was also significantly higher in FAM+, whereas the other echocardiographic parameters were similar to FAM-. CONCLUSIONS: Among the offspring of families with a positive history of hypertension, circulating EO levels and blood pressure are increased. Plasma EO levels are related to alterations of some indexes of diastolic heart function in these individuals.  相似文献   
108.
We developed a simple and fully automated method for detecting artifacts in the R-R interval (RRI) time series of the ECG that is tailored to the intensive care unit (ICU) setting. From ECG recordings of 50 adult ICU-subjects we selected 60 epochs with valid R-peak detections and 60 epochs containing artifacts leading to missed or false positive R-peak detections. Next, we calculated the absolute value of the difference between two adjacent RRIs (adRRI), and obtained the empirical probability distributions of adRRI values for valid R-peaks and artifacts. From these, we calculated an optimal threshold for separating adRRI values arising from artifact versus non-artefactual data. We compared the performance of our method with the methods of Berntson and Clifford on the same data. We identified 257,458 R-peak detections, of which 235,644 (91.5%) were true detections and 21,814 (8.5%) arose from artifacts. Our method showed superior performance for detecting artifacts with sensitivity 100%, specificity 99%, precision 99%, positive likelihood ratio of 100 and negative likelihood ratio <0.001 compared to Berntson’s and Clifford’s method with a sensitivity, specificity, precision and positive and negative likelihood ratio of 99%, 78%, 82%, 4.5, 0.013 for Berntson’s method and 55%, 98%, 96%, 27.5, 0.460 for Clifford’s method, respectively. A novel algorithm using a patient-independent threshold derived from the distribution of adRRI values in ICU ECG data identifies artifacts accurately, and outperforms two other methods in common use. Furthermore, the threshold was calculated based on real data from critically ill patients and the algorithm is easy to implement.  相似文献   
109.
Background: Bioelectrical impedance analysis (BIA) is an inexpensive, non-invasive and fast method to assess body composition. Little is known of the interaction between anti IL 12/23 treatment and body composition. The aim of this study was to evaluate 6- and 12-month changes in body weight, Body Mass Index (BMI) and body composition assessed by BIA in psoriatic patients treated with anti-IL-12/23.

Research design and methods: Demographic and clinical data were collected for each enrolled patient. Physical examination, anthropometric assessment, Psoriasis Area and Severity Index (PASI) assessment and body composition by BIA (single-frequency 50 kHz), were assessed at baseline and at 6 and 12 months of treatment.

Results: A significant decrease in body weight, compared to baseline, in BMI, Fat Mass at month 6 and a significant increase at month 12 for body cellular mass (BCM) and Phase Angle (PhA) were observed. In addition, a significant increase was found for intracellular water.

Conclusion: At baseline, psoriatic patients showed a lower BCM and a lower mean PhA score. During ustekinumab treatment, the mean PhA and BCM scores increased with an improvement in psoriatic disease. Thus, ustekinumab can be an effective drug for improving not only psoriasis but also the general clinical status of patients.  相似文献   

110.
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