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151.
Suligoi B Massi M Galli C Sciandra M Di Sora F Pezzotti P Recchia O Montella F Sinicco A Rezza G 《Journal of acquired immune deficiency syndromes (1999)》2003,32(4):424-428
We evaluated a procedure for identifying recent HIV infections, using sequential serum samples from 47 HIV-positive persons for whom the seroconversion date could be accurately estimated. Each serum sample was divided into two aliquots: one diluted with phosphate-buffered saline and the other diluted with 1 M guanidine. We assayed the aliquots with the automated AxSYM HIV1/2gO test (Abbott Diagnostics Division), without modifying the manufacturer's protocol. We then calculated the avidity index (AI): the ratio of the sample/cutoff value for the guanidine aliquot to that of the phosphate-buffered saline aliquot. We analyzed 216 serum samples: 34 samples were collected within 6 months of seroconversion (recent seroconversions), and 182 were collected after 6 months. The mean AIs, by time from seroconversion, were 0.68 +/- 0.16 (within 6 months) and 0.98 +/- 0.10 (after 6 months) (P < 0.0001). AI of <0.90 correctly identified 88.2% of recent infections but misclassified as recent infections 13.2% of serum samples collected afterward. The probability of an infection being classified as recent and having AI of > or = 0.90 would be 0.7% in a population with 5% recent infections. AI can identify with a certain degree of accuracy recent HIV infections, and being a quantitative index, it provides different levels of sensitivity and specificity, depending on the selected cutoff value. The standard assay procedure is not modified. This test is simple and inexpensive and could be used for surveillance, decision-making in treatment, and prevention. 相似文献
152.
IL-10, an inflammatory/inhibitory cytokine,but not always 总被引:24,自引:0,他引:24
153.
Bertini M Ferrara M De Gennaro L Curcio G Fratello F Romei V Pauri F Rossini PM 《Journal of sleep research》2004,13(1):31-36
Transcranial magnetic stimulation (TMS) is a recently established technique in the neurosciences that allows the non-invasive assessment, among other parameters, of the excitability of motor cortex. Up to now, its application to sleep research has been very scarce and because of technical problems it provided contrasting results. In fact delivering one single suprathreshold magnetic stimulus easily awakes subjects, or lightens their sleep. For this reason, in the present study we assessed motor thresholds (MTs) upon rapid eye movement (REM) and non-rapid eye movement (NREM) sleep awakenings, both in the first and in the last part of the night. Taking into account that a full re-establishment of wake regional brain activity patterns upon awakening from sleep needs up to 20-30 min, it is possible to make inferences about the neurophysiological characteristics of the different sleep stages by analyzing the variables of interest immediately after provoked awakenings. Ten female volunteers slept in the lab for four consecutive nights. During the first night the MTs were collected, following a standardized procedure: 5 min before lights off, upon stage 2 awakening (second NREM period), upon REM sleep awakening (second REM period), upon the final morning awakening (always from stage 2). Results showed that MTs increased linearly from presleep wakefulness to REM sleep awakenings, and from the latter to stage 2 awakenings. There was also a time-of-night effect on MTs upon awakening from stage 2, indicating that MTs decreased from the first to the second part of the night. The increase in corticospinal excitability across the night, which parallels the fulfillment of sleep need, is consistent with the linear decrease of auditory arousal thresholds during the night. The maximal reduction of corticospinal excitability during early NREM sleep can be related to the hyperpolarization of thalamocortical neurons, and is in line with the decreased metabolic activity of motor cortices during this sleep stage. On the contrary, the increase of MTs upon REM sleep awakenings should reflect peripheral factors. We conclude that our findings legitimate the introduction of the TMS technique as a new proper tool in sleep research. 相似文献
154.
155.
Endogenous levels of mRNA for IFNs and IFN-related genes in hepatic biopsies of chronic HCV-infected and non-alcoholic steatohepatitis patients 总被引:3,自引:0,他引:3
Abbate I Romano M Longo R Cappiello G Lo Iacono O Di Marco V Paparella C Spano A Capobianchi MR 《Journal of medical virology》2003,70(4):581-587
To investigate the intra-hepatic activation of the IFN system in patients affected by chronic HCV-infection in comparison with that observed in a non-infectious liver disease such as non-alcoholic steatohepatitis, we measured the liver steady state mRNA levels of interferon-alpha, interferon-beta and interferon-gamma as well as of IFN-related genes (IFNAR-1, STAT1alpha, PKR, 2-5 AS, IRF-1, ICE and IL-18). In HCV-infected subjects, possible correlations of these parameters with viral load and liver injury were also analyzed. Twenty-four chronic untreated HCV-infected subjects and seven patients with non-alcoholic steatohepatitis were enrolled in the study. Liver biopsies were graded according to Knodell scores. Intra-hepatic mRNA levels of IFNs and related genes were assessed by semi-quantitative RT-PCR. In comparison with non-alcoholic steatohepatitis, in HCV-infected subjects IFN-alpha and -beta mRNA levels were significantly lower, whereas IFN-gamma, IFNAR-1, STAT1alpha IRF-1, and IL-18 mRNA were upregulated. Moreover, IFN-gamma mRNA steady state levels were correlated positively with those of IFNAR-1, IRF-1, and IL-18, suggesting a coordinated induction of these genes. Although plasma viral load was correlated inversely with IL-18-specific mRNA, viral load was not related to liver injury. IFN-gamma and IRF-1 mRNA levels were correlated positively with ALT, but not with the grading or staging. Conversely, IFN-alpha and -beta mRNA levels were higher in livers with lower staging scores. These findings support the hypothesis that in chronic HCV infection there is an imbalance between an upregulated IFN-gamma system and a downregulated IFN-alpha and -beta system, probably due to a mixed effect exerted by HCV-specific and inflammatory non-specific factors. 相似文献
156.
A phase II trial of temozolomide and IFN-alpha in patients with advanced renal cell carcinoma. 总被引:1,自引:0,他引:1
Usha Sunkara Janet R Walczak Lori Summerson Theresa Rogers Mario Eisenberger Samuel Denmeade Roberto Pili Carol Ann Huff Victoria Sinibaldi Michael A Carducci 《Journal of interferon & cytokine research》2004,24(1):37-41
The combination of temozolomide (TEM) and interferon-alpha (IFN-alpha) previously demonstrated a 30% response rate in metastatic melanoma. A single institution, phase II trial evaluating the efficacy of TEM/IFN in patients with advanced renal cell carcinoma (RCC) was conducted. Safety and tumor response were the main outcomes. Eligible patients received 200 mg/m(2)/day TEM orally on days 1-5 every 28 days, with IFN 2.5 million U/m(2)/day subcutaneously (s.c.) three alternate days/week for days 1-15 first cycle, then 5 million U/m(2)/day s.c. 3 alternate days/week throughout each 28-day cycle. Efficacy was evaluated every 8 weeks, and dose-limiting toxicities (DLTs) were treated with dose reductions of the culprit drug. Sixteen patients (ages 37-67) were initially enrolled. Of the 14 evaluable patients, there was one minor response. Best response was stable disease, with 7 patients remaining on study for > or =6 months. Five were alive for more than 2 years, and 2 remain alive at 45 and 50 months after enrollment. DLTs included TEM-induced myelosuppression and IFN-induced fever/chills. Other toxicities were mild to moderate (grades 1-3). The combination of TEM/IFN proved quite tolerable. This regimen appears inactive in terms of response in this population with poor prognosis, but the patients with stable disease > or =6 months remain of interest. 相似文献
157.
Giorgino T Azzini I Rognoni C Quaglini S Stefanelli M Gretter R Falavigna D 《International journal of medical informatics》2005,74(2-4):159-167
Recent advances in automatic speech recognition and related technologies allow computers to carry on conversations by telephone. We developed an intelligent dialogue system that interacts with hypertensive patients to collect data about their health status. Patients thus avoid the inconvenience of traveling for frequent face to face visits to monitor the clinical variables they can easily measure at home; the physician is facilitated in acquiring patient information and cardiovascular risk, which is evaluated from the data according to noted guidelines. Controlled trials to assess the clinical efficacy are under way. 相似文献
158.
Alessandro Antonelli Mario Rotondi Poupak Fallahi Paola Romagnani Silvia Martina Ferrari Ele Ferrannini Mario Serio 《Journal of interferon & cytokine research》2005,25(9):547-552
Circulating levels of cytokines are deeply influenced by aging, and few data about serum chemokines are available. The aim of this study was to evaluate the influence of aging on circulating CXCL10. One hundred forty healthy subjects (70 males and 70 females), 10-79 years of age, underwent fasting plasma glucose, total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), triglyceride, and CXCL8 serum assay. Thyroid hormone testing for thyroid-stimulating hormone (TSH), antithyroglobulin (AbTg), and antithyroperoxidase (AbTPO) autoantibodies and thyroid ultrasonography were performed in all subjects to exclude the presence of clinical or subclinical thyroid disease. Serum CXCL10 levels were assayed in all subjects and found to be increased in 14 of 70 females (20%) and in 4 of 70 males (5.7%) (p = 0.01). In a multiple linear regression model including age, body mass index (BMI), systolic and diastolic blood pressure, glycemia, total cholesterol, HDL, LDL, triglycerides, TSH, AbTPO, AbTg, and CXCL8, only age was significantly related to CXCL10 [C.R. 1.30 (0.28-2.33), p = 0.001]. No relationship was present between CXCL8 serum levels and age, suggesting a specificity of CXCL10 elevation as a function of age. Results of this study, performed in healthy subjects on an age gradient, demonstrate an increase in serum CXCL10 with advancing age overall in females, supporting the hypothesis of enhanced Th1 immune responses in aging. 相似文献
159.
Lipid abnormalities in HIV-infected patients are not correlated with lopinavir plasma concentrations
160.
Sensitive and viable identification of antigen-specific CD8+ T cells by a flow cytometric assay for degranulation 总被引:15,自引:0,他引:15
Betts MR Brenchley JM Price DA De Rosa SC Douek DC Roederer M Koup RA 《Journal of immunological methods》2003,281(1-2):65-78
Flow cytometric detection of antigen-specific CD8+ T cells has previously been limited to MHC-class I tetramer staining or intracellular cytokine production, neither of which measure the cytolytic potential of these cells. Here we present a novel technique to enumerate antigen-specific CD8+ T cells using a marker expressed on the cell surface following activation induced degranulation, a necessary precursor of cytolysis. This assay measures the exposure of CD107a and b, present in the membrane of cytotoxic granules, onto the cell surface as a result of degranulation. Acquisition of cell surface CD107a and b is associated with loss of intracellular perforin and is inhibited by colchicine, indicating that exposure of CD107a and b to the cell surface is dependent on degranulation. CD107a and b are expressed on the cell surface of CD8+ T cells following activation with cognate peptide, concordant with production of intracellular IFNgamma. Finally, CD107-expressing CD8+ T cells are shown to mediate cytolytic activity in an antigen-specific manner. Measurement of CD107a and b expression can also be combined with MHC-class I tetramer labeling and intracellular cytokine staining to provide a more complete assessment of the functionality of CD8+T cells expressing cognate T cell receptors (TCR). 相似文献