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101.
BACKGROUND: The chemokine receptors CXCR4 and CCR5 have been identified as the major coreceptors for HIV-1 on CD4+ cells and macrophages. The natural ligands for these receptors are SDF-1 and the beta-chemokines (MIP-1alpha, MIP-1beta, RANTES), respectively, and are the products of a variety of immune cells, including CD8+ T lymphocytes. STUDY DESIGN/METHODS: We hypothesized that the ability to stimulate the natural ligands for these receptors using an immune based therapy might influence in vivo chemokine receptor expression. RESULTS: In vivo CXCR4 expression remained stable after treatment with an HIV-1 Immunogen (REMUNE), whereas CCR5 expression on CD4+ T cells decreased (p < .05). Furthermore, HIV-1 antigen-specific production of beta-chemokines in vitro was also augmented (P < .05). CONCLUSIONS: These preliminary results suggest that this HIV-1-specific immune-based therapy can stimulate antigen-specific beta-chemokine production in vitro and downregulate CCR5 receptor expression on CD4 cells in vivo.  相似文献   
102.
Mixed-lineage leukemia (MLL) fusion proteins are potent inducers of leukemia, but how these proteins generate aberrant gene expression programs is poorly understood. Here we show that the MLL-AF4 fusion protein occupies developmental regulatory genes important for hematopoietic stem cell identity and self-renewal in human leukemia cells. These MLL-AF4-bound regions have grossly altered chromatin structure, with histone modifications catalyzed by trithorax group proteins and DOT1 extending across large domains. Our results define direct targets of the MLL fusion protein, reveal the global role of epigenetic misregulation in leukemia, and identify new targets for therapeutic intervention in cancer.  相似文献   
103.
Summary The volume of the adenomatous mucosa (V), the area of the surface epithelium (Ss), the area of the glandular epithelium (Sg), and theSg:Ss ratio were calculated in a series of 14 adenomatous polyps (APs) of a case of multiple polyposis of the colon. The equation of simple allometry was used to study the relative growth of the four series of values.Ss grew isometrically with size;Sg overgrewSs and accounted for most of the increase inV. TheSg:Ss ratio increased withSg andV.  相似文献   
104.
OBJECTIVE: To compare nasal symptomatology and function and local concentrations of estradiol (E2), estradiol receptor (ERalpha), vasoactive intestinal peptide (VIP), substance P (SP) and neuropeptide Y (NPY) in nasal biopsies of 20 postmenopausal women complaining of paradoxical nasal stuffiness before and after treatment with intranasal or transdermal E2. DESIGN: Twenty healthy postmenopausal women willing to start hormone therapy (HT) were allocated to one of two groups, using a computer-generated randomization list.Ten postmenopausal women were treated with transdermal 17beta-estradiol 50 microg daily plus nomegestrole acetate 5 mg/day for 12 days per 28-day cycle for 6 months (Group A). Ten postmenopausal women were treated with intranasal 17beta-estradiol 300 microg/day (one spray delivery of 150 microg per nostril) plus nomegestrole acetate 5 mg/day for 12 days per 28-day cycle for 6 months (Group B). Fourteen fertile women undergoing nasal mucosa biopsy during plastic surgery were used as controls for the immunohistochemical evaluation (Group C).All women in groups A and B underwent evaluation of nasal stuffiness score, mucociliary transport time, rhinoscopy, and active anterior rhinomanometry at the beginning of the study and after, VIP, SP, and 6 months of HT. Nasal biopsies and evaluation of local concentrations of E2, ERalpha NPY were performed in groups A and B before and after 6 months of HT and in group C. RESULTS: Both intranasal and transdermal HT improve nasal symptomatology and nasal mucosa appearance and reduce mean mucociliary transport time. The effectiveness of intranasally administered therapy at improving nasal function is significantly better than transdermal therapy. In comparison with premenopausal controls, untreated postmenopausal women of group A and B showed significantly decreased immunopositivity for E2, ERalpha, and SP. HT induced a significant increase in E2, ERalpha, VIP, and SP and a decrease in NPY immunopositivity. Intranasal therapy was associated with a significantly higher immunopositivity for VIP and SP. CONCLUSIONS: HT improves nasal function and symptomatology in postmenopausal women with paradoxical nasal stuffiness, modulating nasal mucosa function through an action on cholinergic, adrenergic, and sensory peptides. Intranasally administered HT is more effective at improving nasal function than transdermal HT.  相似文献   
105.
Ambulatory blood pressure was studied as a function of posture, place, and mood in 131 subjects classified according to race, gender, and hypertensive status. The effect of posture was significant and explained a substantial proportion of within-subject variability. After controlling for posture, significant place and mood effects were observed when subjects were sitting but not when they were standing. Home vs. work differences in both systolic and diastolic blood pressure were significantly greater in Whites than in Blacks. Similar differences in systolic blood pressure were greater in mild hypertensive than in normotensive subjects. The results of this study underscore the need to control for effects of posture when interpreting ambulatory blood pressure readings.  相似文献   
106.
107.
Hepatitis B virus (HBV) is a virus that infects about 350,000,000 people worldwide with a clinical spectrum of acute hepatitis, the healthy carrier state, cirrhosis and hepatocellular carcinoma (HCC). The outcome of HBV infection is the result of complicated viral-host interactions. As in other infections with non-cythopatic viruses, the immune response is thought to play a crucial role in disease pathogenesis but there is increasing evidence that a variety of viral mechanisms, some depending on the function of virally encoded proteins, have a profound impact on the infected hepatocytes, the liver microenvironment, and host anti-viral responses. Indeed, the virus has evolved multiple mechanisms to ensure its success in infecting a susceptible host. The essential aspects of the life cycle of HBV and the host immune response are reviewed and recent new developments in the molecular virology of HBV, including experimental animal models, in the role of accessory viral proteins in disease pathogenesis and HCC development and in the characterisation of the T cell response in the control of HBV infection, are highlighted.  相似文献   
108.
Primary systemic carnitine deficiency or carnitine uptake defect (OMIM 212140) is a potentially lethal, autosomal recessive disorder characterized by progressive infantile‐onset cardiomyopathy, weakness, and recurrent hypoglycemic hypoketotic encephalopathy, which is highly responsive to L ‐carnitine therapy. Molecular analysis of the SLC22A5 (OCTN2) gene, encoding the high‐affinity carnitine transporter, was done in 11 affected individuals by direct nucleotide sequencing of polymerase chain reaction products from all 10 exons. Carnitine uptake (at Km of 5 μM) in cultured skin fibroblasts ranged from 1% to 20% of normal controls. Eleven mutations (delF23, N32S, and one 11‐bp duplication in exon 1; R169W in exon 3; a donor splice mutation [IVS3+1 G > A] in intron 3; frameshift mutations in exons 5 and 6; Y401X in exon 7; T440M, T468R and S470F in exon 8) are described. There was no correlation between residual uptake and severity of clinical presentation, suggesting that the wide phenotypic variability is likely related to exogenous stressors exacerbating carnitine deficiency. Most importantly, strict compliance with carnitine from birth appears to prevent the phenotype. © 2002 Wiley‐Liss, Inc.  相似文献   
109.
Summary The mechanical power (Wtot, W·kg–1) developed during ten revolutions of all-out periods of cycle ergometer exercise (4–9 s) was measured every 5–6 min in six subjects from rest or from a baseline of constant aerobic exercise [50%–80% of maximal oxygen uptake (VO2max)] of 20–40 min duration. The oxygen uptake [VO2 (W·kg–1, 1 ml O2 = 20.9 J)] and venous blood lactate concentration ([la]b, mM) were also measured every 15 s and 2 min, respectively. During the first all-out period, Wtot decreased linearly with the intensity of the priming exercise (Wtot = 11.9–0.25·VO2). After the first all-out period (i greater than 5–6 min), and if the exercise intensity was less than 60% VO2max, Wtot, VO2 and [la]b remained constant until the end of the exercise. For exercise intensities greater than 60% VO2max, VO2 and [la]b showed continuous upward drifts and Wtot continued decreasing. Under these conditions, the rate of decrease of Wtot was linearly related to the rate of increase of V [(d Wtot/dt) (W·kg–1·s–1) = 5.0·10–5 –0.20·(d VO2/dt) (W·kg–1·s–1)] and this was linearly related to the rate of increase of [la]b [(d VO2/dt) (W·kg–1·s–1) = 2.310–4 + 5.910–5·(d [la]b/dt) (mM·s–1)]. These findings would suggest that the decrease of Wtot during the first all-out period was due to the decay of phosphocreatine concentration in the exercising muscles occurring at the onset of exercise and the slow drifts of VO2 (upwards) and of Wtot (downwards) during intense exercise at constant Wtot could be attributed to the continuous accumulation of lactate in the blood (and in the working muscles).  相似文献   
110.
Objectives: To study etiological, epidemiological and clinical features of 97 cases of acute meningitis. Methods: Ninety-seven cases of acute meningitis were examined in adult HIV-negative patients admitted to the Infectious Diseases Unit of the Azienda Ospedale-Universita S. Anna in Ferrara. Demographic, etiological, epidemiological and clinical data were analyzed. Results: All cases were divided into two groups according to the macroscopic aspect of cerebrospinal fluid (CSF): purulent CSF (50 cases) or non-purulent CSF (47 cases). Purulent CSF meningitis more frequently affected male patients (64% vs 47%) and older patients (average 52 vs 44 years). The main epidemiological features in both groups were underlying bacterial diseases (i.e. otomastoiditis and/or sinusitis in 50% of pneumococcal meningitis) and iatrogenic immunodeficiency. From a clinical point of view the following alterations in the state of consciousness (stupor, confusion and coma) were most frequently found in purulent meningitis. The following non purulent forms of meningitis were diagnosed: 5 tubercular, 3 viral infections, 2 by Listeria monocytogenes, 1 by Entoameba histolytica, 1 by Cryptococcus neoformans and 35 (74,4%) unknown causes. Purulent meningitis were: 20 (40%) Streptococcus pneumoniae, 10 Neisseria meningitidis, 3 Staphylococcus aureus, 2 Escherichia coli, 1 Haemophilus influenzae and 1 Pseudomonas aeruginosa; 13 cases were unidentified. From 1989 to 1993 and from 1994-98 both groups of meningitis increased; respectively from 17 to 30 cases for non-purulent meningitis and from 18 to 32 cases for purulent meningitis. Meningitis due to Streptococcus pneumoniae increased from 27.7% to 46.8% during the period 1994-98. Conclusions: The study shows the high incidence of pneumococcal meningitis, during 1994-98, because a large number of patients with sinusitis and otomastoiditis were observed. The incidence of meningococcal meningitis appears stable. These data confirm the importance of timely diagnosis and correct therapy for such infections with reserved prognosis.  相似文献   
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