HIV vaccines: a brief overview.

The scope of the article is to review the different approaches that have been used for HIV vaccines. The review is based on articles retrieved by PubMed and clinical trials from 1990 up to date. The article discusses virus complexity, protective and non-protective immune responses against the virus, and the most important approaches for HIV vaccine development.

Increased lipid peroxidation and abnormal fatty acid profiles in seminal and blood plasma of normozoospermic males from infertile couples.

BACKGROUND: Reactive oxygen species (ROS) are essential for sperm function. However, excessive ROS production can impair sperm function and might be a factor contributing to male infertility. METHODS: We investigated the levels of arachidonic acid (AA) and docosahexaenoic acid (DHA) as well as lipid peroxidation, as represented by thiobarbituric acid reactive species (TBARS), in blood and seminal plasma of 38 normozoospermic males from infertile couples (NSI-males), compared with that of 17 fertile volunteers (FV-males). RESULTS: TBARS levels in blood and seminal plasma were higher in NSI-males than in FV-males (P < 0.0002, P < 0.0003, respectively), as were AA levels (P < 0.0003, P < 0.00004, respectively). On the contrary, the blood and seminal plasma levels of DHA were lower in NSI-males than in FV-males (P < 0.02 and P < 0.05, respectively). The AA/DHA ratios in blood and seminal plasma were higher in NSI-males than in FV-males (P < 0.003, P < 0.0007, respectively). Significant correlations between seminal and blood plasma levels of TBARS (P < 0.0001, r = 0.548), AA (P < 0.0001, r = 0.571) and DHA (P < 0.0001, r = 0.506) were found. CONCLUSIONS: Our data provide new insight into lipid metabolism in male infertility and indicate that systemic oxidative stress resulting in increased lipid peroxidation and an altered fatty acid profile may be, at least in part, responsible for infertility even in normozoospermic males.

Proximal esophageal adenocarcinoma presenting as a thyroid mass: case report and review of the literature.

Metastatic disease to the thyroid is not an unusual finding at autopsies, but it is rare to be found in clinical situations. We present the first case of adenocarcinoma of the proximal esophagus presenting as a thyroid mass in a young healthy patient without any previous history of malignancy. This case highlights the importance of thorough work-up when addressing a thyroid mass. A high index of suspicion should be maintained in order to be able to detect unusual etiologies of thyroid conditions, especially when histopathology is not characteristic for primary thyroidal malignancies.

Toll-like receptors, cytokines and the immunotherapeutics of asthma.

Asthma is a complex disease caused by a poorly characterized set of genetic and environmental factors whose pathology is a result of immune dysregulation. Toll-like receptors are pathogen associated molecular pattern receptors expressed by many airway and pulmonary tissues as well as cells of the innate and adaptive immune system. Ligation of toll-like receptors can lead to a change in the expression levels of multiple inflammatory and anti-inflammatory mediators which are involved in the pathogenesis of asthma. These ligands and their receptors are therefore prime candidates in the search for immunotherapeutic treatments of asthma. The use of murine models of allergic asthma as tools for the genetic dissection of this disease should allow the molecular mechanisms underlying asthma to be identified and possibly used as further immunotherapeutic targets.

Skeletal muscle inflammation and nitric oxide in patients with COPD.

In chronic obstructive pulmonary disease (COPD) the presence of systemic inflammation has been associated with peripheral muscle abnormalities and weight loss. To study whether inflammatory factors are important in these processes, the present study compared the skeletal muscle levels of nitrite, nitrate, nitrotyrosine, neuronal, endothelial and inducible nitric oxide synthases (nNOS, eNOS, and iNOS, respectively), and inflammatory markers (tumour necrosis factor (TNF)-alpha, CD154 and CD163) in 15 patients (forced expiratory volume in one second 43+/-11%) and 14 controls. All these markers were also compared between patients with normal and low body weight. Nitrite (12.5+/-2.6 versus 17.0+/-3.4 micromol.mg(-1) protein), nitrate (20.7+/-2.4 versus 24.4+/-4.5 micromol.mg(-1) protein) and eNOS (31.9+/-4.6 versus 43.6+/-7.5 ng.mg(-1) protein) were lower in COPD patients than in controls. Nitrotyrosine (25.6+/-5.4 versus 6.6+/-3.3 ng.mg(-1) protein), iNOS expression (32+/-9.5 versus 7.16+/-2.7 ng.mg(-1) protein), TNF-alpha (257+/-160 versus 48.3+/-4.4 pg.mg(-1) protein) and CD163 (6.4+/-2.1 versus 0.8+/-0.4 ng.mg(-1) protein) were higher in COPD patients than in controls. CD154 levels were 15.7+/-7.0 ng.mg(-1) protein in COPD patients and undetectable in controls. Similar levels of all these markers were observed in COPD patients with normal and low body weight. In conclusion, these findings suggest the presence of an inflammatory process in the muscle tissue of chronic obstructive pulmonary disease patients, and argue in favour of its participation in the pathogenesis of skeletal muscle abnormalities.

Inflammation and nitric oxide production in skeletal muscle of type 2 diabetic patients.

An inflammatory process may be involved in nitric oxide production in skeletal muscle of type 2 diabetic patients. Nitric oxide generation in skeletal muscle was assessed in 14 non-complicated type 2 diabetic patients and in 12 healthy subjects. In samples of quadriceps femoris muscle, endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase (iNOS), nitrite, nitrate and nitrotyrosine were determined. The macrophage-specific antigen CD163, the T-cell membrane factor CD154 and tumour necrosis factor-alpha (TNF-alpha) were also assayed. In six patients, ultrastructural analysis of muscle was performed. Nitrites and nitrates were increased in patients as compared to controls (22.7+/-4.5 and 32.7+/-7.0 vs 16.0+/-2.9 and 22.8+/-4.0 micromol/mg protein; P<0.001, Mann-Whitney U test). Endothelial NOS was similar in diabetic and control subjects (36.4+/-13.8 vs 36.3+/-6.8 ng/mg protein), contrasting with the significant increase of iNOS recorded in patients (34.3+/-13.0 vs 8.5+/-2.8 ng/mg protein, P<0.00002). Nitrotyrosine levels were higher in the patient than in the control group (42.1+/-24.4 vs 10.3+/-2.5 ng/mg protein, P<0.00002), as were CD163 (10-fold) and TNF-alpha (fourfold) levels. Furthermore, CD154 levels were detectable only in the patient samples (10.2+/-5.3 ng/mg protein). By multiple-regression analysis, changes in glycated haemoglobin values could predict 96% variation in nitrotyrosine. Macrophages were present in all muscle samples analysed by electromicroscopy. The increased levels of CD163, CD154 and TNF-alpha indicate that an inflammatory process occurs in skeletal muscle of type 2 diabetic patients. This may contribute to iNOS induction, muscle damage and insulin resistance.

Activity profile in multiple sclerosis: an integrative approach. A preliminary report.

In order to define an activity profile in patients with multiple sclerosis (MS), T-cell subpopulations and proliferative responses to myelin basic protein (MBP) associated with anti-MBP antibodies, nitrotyrosine levels in serum and cerebrospinal fluid (CSF), and serum CD40L (sCD154) were simultaneously assessed in 29 consecutive and untreated MS patients. When compared to controls, patients in secondary progressive stable (SP/I), or in full remission (RR/I) stages, individuals with secondary progressive active disease (SPIA) or in acute relapse (RR/A) showed a significant decrease of CD4/CD45RA+ T cells associated with an increase of absolute numbers of CD4/45R0+ T cells (p < 0.001). In addition, in vitro-specific T-cell proliferative responses against MBP (SP/A, RR/A, SP/I: p < 0.001 versus controls) in association with augmented sCD154 serum levels (SP/A, RR/A, versus controls p < 0.001) and a significant increase of both CSF and serum levels of anti-MBP antibodies and nitrotyrosine levels (p < 0.001) were also found. Thus, the simultaneous evaluation of antibody and cell-mediated immunopathological parameters, along with the effector mediators of inflammation such as the nitric oxide products, offers a new integrative approach to characterize markers of clinical activity in MS patients, which may be used at the moment of the initial diagnosis and during an apparent recurrences of the disease to monitor therapeutic protocols and to determine whether immune-based nerve destruction mechanisms are still operating in patients with few clinical findings.

Actividad de la enzima lipasa lipoproteica y la concentración de ácidos grasos libres en el M. gluteus Medius de caballos pura sangre afectados con rabdomiólisis / Enzime lipoprotein lipase activity and the free fatty acids concentration in the gluteus medius muscle of horse affected by rhabdomyolysis

El sobreentrenamiento de los caballos pura sangre de carrera puede producir la rabdomiólisis, enfermedad. En el presente trabajo se estudia si la rabdomiólisis afecta a la lipasa lipoproteica y subsecuentemente a los niveles de ácidos grasos libres en el músculo esquelético. Se determinó la actividad de la enzima lipasa lipoproteica (ALPL) y la concentración de ácidos grasos libres (AGL) en muestras del músculo Gluteus medius de 12 caballos pura sangre de carrera (CPSC), y de 12 CPSC con rabdomiólisis. En los caballos con rabdomiólisis se observó una disminución significativa tanto de la ALPL (M ñ SE, 22,15 ñ 2,29 nmoles AGL/min.g en control vs 16,91 ñ 1,25 nmoles AGL/min.g en rabdomiólisis; p< 0,03) como de la concentración de AGL (1,45 ñ 0,27 nmoles AGL/g in control vs 0,86 ñ 0,06 nmoles AGL/g en rabdomiólisis; p< 0,01). Se concluye que la rabdomiólisis afecta la actividad oxidativa muscular

Antihypertensive treatment decreased serum leptin levels in severe preeclampsia during pregnancy.

BACKGROUND: Plasma leptin levels in preeclamptic patients have been reported to be similar compared to those of normotensive pregnant women. Nonetheless, no reports have dealt with the effect of antihypertensive treatment and leptin in preeclamptic patients. METHODS: The study involved three groups of a similar age, body mass index and weeks of gestation. The groups were 30 normal pregnant women and 23 pregnant women with severe preeclampsia (SPE). The SPE patients were not treated prior to admission and the treatment was a single dose of alpha-methyldopa or hydralazine alone or in combination. The samples were taken at random in the afternoon (isotonic saline or pharmacological treatment) and 1 h before and after the treatment was given. Leptin serum levels were determined by a commercial sandwich ELISA assay. RESULTS: Leptin levels of the SPE group prior to the treatment were similar to the levels recorded for the normal pregnant women. However, after 1 h leptin levels were significantly higher (p < 0.001) in the nontreated patients (8.0 +/- 1.5) compared with those treated (5.15 +/- 0.9). CONCLUSION: These marked differences between treated and nontreated patients suggest that leptin levels may be modulated by a single antihypertensive treatment in preeclamptic patients with a discrete increase in blood pressure.

Muscle fiber composition and capillarization in relation to metabolic alterations in hypertensive men.

The aim of this study was to determine if there is a relationship among skeletal muscle fiber composition, capillarization, blood pressure (BP) and/or the components of the metabolic syndrome. Two groups were compared: 8 recently diagnosed, untreated, hypertensive men (BP > or = 140/90) and 7 normotensive men as controls. Muscle biopsies were taken from the vastus lateralis part of quadriceps femoris muscle in order to assess: fiber type proportion, capillarization, hexokinase, citrate synthase, beta-hydroxyacyl CoA dehydrogenase activities; lipoprotein lipase mass and activity, free fatty acids and triglycerides. Serum levels of insulin, glucose, cholesterol, uric acid and triglycerides were also assayed. Hypertensive patients had higher insulin levels and insulin resistance [homeostasis model assessment (HOMA)], a decreased hexokinase activity and an increase of muscle lipoprotein lipase mass as compared to controls. Interestingly, correlations among values differ in each group. The percentage of type IIB fibers was related to diastolic BP (blood pressure) in control and to mean BP in hypertensive subjects. Serum cholesterol and glucose were inversely related to the percentage of type I fibers in the control subjects. Negative correlations between capillarization and glucose, cholesterol and uric acid levels were found in control subjects. In all subjects, a strong correlation was found between SBP (systolic BP) and DBP (diastolic BP), and insulin resistance (IR) and uric acid levels. Muscle fiber type proportion and capillarization were related to blood pressure and components of the metabolic syndrome.

Percutaneous interventions for lower extremity peripheral vascular disease.

Peripheral vascular disease of the lower extremities is an important cause of morbidity that affects up to 10 million people in the United States. The primary care physician can easily identify patients who are at risk for the disease with a questionnaire and a relatively simple test-the ankle brachial index. More than 70 percent of patients diagnosed with the disease remain stable or improve with conservative management. Those who do not improve may undergo contrast angiography or magnetic resonance angiography, which may be used in planning for surgery or percutaneous intervention. Surgical bypass is the gold standard for extensive vascular occlusive disease, but endovascular interventions, including percutaneous transluminal angioplasty and stent placement, are being used more frequently, particularly in patients with significant comorbid conditions.

Serum leptin levels in different types of hypertension during pregnancy.

We determined the serum levels of leptin in 96 pregnant women with body mass index between 20 to 30, 30 normal (NP), 26 with mild preeclampsia (MPE), 27 with severe preeclampsia (SPE), 6 with chronic hypertension plus preeclampsia (CHT+PE) and 7 with chronic hypertension (CHT). A significant (p < 0.01) decrease in leptin levels was observed in the SPE group when compared with the NP group. On the contrary, significant (p < 0.05) increases were observed in the CHT and CHT+PE groups when compared with the NP group. Leptin levels were significantly higher in the MPE (p < 0.001), CHT (p < 0.01) and CHT+PE (p < 0.5) groups when compared with the SPE. No significant differences were observed in the CHT group when compared with CHT+PE. Moreover, a positive correlation was encountered (r = 0.6, p < 0.001) between platelet number and leptin levels for all the patients with preeclampsia. These results suggest that leptin levels may be useful metabolic parameter in different types of hypertension during pregnancy.

Metabolic changes in DOCA-salt hypertensive rats.

In a previous report, we observed an altered proportion of fiber types and a reduction of capillary per fiber ratio in extensor digitorus longus (EDL) and soleus (SOL) muscles of deoxicorticosterone acetate (DOCA)-salt hypertensive rats when compared with controls. The aim of the present study was to ascertain various carbohydrate and lipid enzyme activities and substrates that may be involved in the morphological changes reported. In the SOL muscle of hypertensive rats, glucose, glycogen and triglycerides (TG) levels were increased, citrate synthase (CS) and beta-hydroxy-acyl-CoA dehydrogenase (HAD) activities were reduced, while hexokinase (HK) and lipoprotein lipase (LPL), LPL mass, lactate and free fatty acids (FFA) levels were unchanged. In EDL muscles of hypertensive rats, glycogen levels and LPL mass were higher than in controls, while CS, HAD, HK, and LPL activities and glucose, lactate, FFA and TG levels were unmodified. Serum levels of insulin, TG, cholesterol and FFA were increased while glucose levels were decreased and high-density lipoprotein-cholesterol levels were similar in hypertensive rats when compared with controls. In conclusion, hypertensive rats showed increased glycogen in both EDL and SOL muscles, with hyperinsulinemia and reduced glycemia. Hyperinsulinemia might have been a compensatory response to insulin resistance. The oxidative capacity of SOL muscle was reduced indicating that glucose uptake was conduced via non-oxidative metabolism. TG, FFA and cholesterol were increased in serum and TG in SOL muscle.

HCV RNA sequences in eosinophils of chronic HCV-infected patients.

In the present study we examined the presence of Hepatitis C virus (HCV) RNA sequences in eosinophils (Eos) isolated from 10 chronically HCV-infected patients. At the time of the study patients showed levels of alanine aminotransferase (ALT) and aspartate aminotranferase (AST) above the normal upper limits (129 IU/L +/- 77 and 56.2 IU/L +/- 40, respectively). Absolute and relative total leukocyte and Eos counts were within the normal range. Highly purified eosinophils (> 98 %) were obtained by Ficoll-Hypaque (d = 1.114 g/mL) and Percoll gradient centrifugation following by immunomagnetic absorbtion to cell specific antibodies. Mononuclear cells (MN) and neutrophils (Neu) were also purified from these patients. PCR analysis of these cell populations revealed the presence HCV RNA sequences in 4/10 Eos, 6/10 MN and 2/10 Neu cell samples. The results suggest that, in addition to MN and Neo cells, Eos might also be susceptible to HCV infection.

Expression of low-density lipoprotein receptors in peripheral blood and tonsil B lymphocytes.

B lymphocytes, purified from peripheral leucocytes from young normolipaemic humans, expressed and internalized low-density lipoprotein receptors (LDLR). The expression was assessed by a monoclonal anti-LDLR. The internalization of LDL was assessed by LDL labelled with 125I (125I-LDL) and 1,1'-dioctadecyl-3,3,3',3' tetramethyl-indocarboxycyanine perchlorate (LDL-DiI). The expression of LDLR, assessed by anti-LDLR, was: 38 +/- 8% (n = 5) for fresh purified cells, 60 +/- 10% (n = 12) for non-stimulated cells, 79 +/- 5% (n = 10) for IL-2 (100 U/ml)-stimulated cells and 95 +/- 5% (n = 8) for pokeweed mitogen (PWM) (1:200 dilution)-stimulated cells. The optimal concentrations of agonist were 100 U/ml of IL-2, and 1:200 dilution of PWM. IL-2 and PWM increased the internalization of LDL-DiI by 1.5-fold. The internalization of LDL-DiI was maximal at 60 microg of protein/ml (48 +/- 8%). Scatchard analysis revealed a Kd of 3.2 +/- 0.22 x 10(-8) M and 2180 +/- 190 binding sites in non-stimulated cells, a Kd of 7.73 +/- 0.36 x 10(-9) M and 12,500 +/- 430 binding sites for IL-2 (100 U/ml)-stimulated cells, and a Kd of 7.2 +/- 0.43 x 10(-9) M and 13,250 +/- 450 binding sites for PWM (1:200 dilution)-stimulated cells. Lineweaver-Burk analysis of LDL binding (LDL-DiI) revealed that the apparent Kd for non-stimulated cells was 1.3 +/- 0.11 x 10(-8) M, and 9.2 +/- 0.2 x 10(-9) M and 7.5 +/- 0.25 x 10(-9) M for IL-2- and PWM-stimulated cells, respectively. B lymphocytes from tonsils also showed a high expression of LDLR assessed with anti-LDLR (70 +/- 6%). The high expression of LDLR and the avid internalization of LDL suggest that LDL may be important for B cell physiological responses.

Increased peroxide production by polymorphonuclear cells of chronic hepatitis C virus-infected patients.

To evaluate the oxidative burst in hepatitis C virus (HCV) infection, intracellular hydrogen peroxide (H2O2) production of polymorphonuclear (PMN) cells isolated from 15 chronic HCV-infected patients and 11 controls was assessed by flow cytometry in a time kinetic. Under nonstimulated and phorbol myristate acetate (PMA)-stimulated conditions, H2O2 production was higher in HCV-infected patients than in controls (P <0.05) at the time points of 20, 30, and 40 min. A positive correlation between H2O2 production by PMA-stimulated cells and serum levels of alanine aminotransferase and aspartate aminotransferase was found in the HCV-infected patients (r = 0.877, P <0.01 and r = 0.9351, P <0.001, respectively). RT-PCR analysis of purified mononuclear (MN) and PMN cells from HCV-infected patients revealed the presence of HCV RNA in 60% of MN and 27% of PMN cell samples. These results suggest that a functional alteration of PMN cells is manifested in this chronic viral infection which may represent an additional factor in the development of liver lesions.

Characterization of local memory cells in stage-classified pulmonary tuberculosis: preliminary observations.

Immunophenotype analysis and proliferative responses were investigated in bronchoalveolar lavage (BAL) cells from 21 patients with stage-classified tuberculosis: six with localized pulmonary infiltrate (LPI); seven with diffuse pulmonary infiltrate (DPI); and eight with pleural effusions (PE). Bronchoalveolar lavage cells from these patients contained a high number of cells/ml. The macrophage number was significantly lower in the DPI group (P < 0.05) compared to the LPI or PE groups. Conversely, neutrophils were markedly increased in DPI patients compared to LPI (P < 0.01) and PE (P < 0.01) patients. Lymphocyte infiltration (97.7 +/- 2.3% CD3+, > 83% alphabeta+ and CD4+ > CD8+) was observed in the three groups. A significant increase in the number of total lymphocytes (P < 0.01) and CD4+ cells (P < 0.05) was observed in the LPI group compared to the PE group. In the LPI group CD4+CD45RO+ cell infiltration was higher than CD4+CD45RA+ cells (P < 0.001), contrasting to similar numbers of these subpopulations in the DPI group. Lymphocytes from three out of three LPI patients (alphabeta+CD4+CD45RO+) responded against tuberculin purified protein derivative contrasting to the unresponsiveness of five patients with either DPI or PE. This impaired response was reverted in two out of five patients by using peripheral blood monocytes instead of alveolar macrophages. It is suggested that, in humans, alphabetaCD4+CD45RO cells are the main lymphocyte type involved in the initial local cell-mediated immune response against Mycobacterium tuberculosis.

Effect of patient position on sonographically measured renal length in neonates, infants, and children.

OBJECTIVE: Renal length as measured on sonography is fundamental in the evaluation of renal disease in children. Understanding the effect of patient position and imaging plane on measured renal length is important for the appropriate use of the standards for interpretation. The goal of this study was to determine how measurement of renal length on sonograms is affected by changes in patient position and imaging plane. SUBJECTS AND METHODS: One hundred seventy-six neonates, infants, and children who were 2 days to 17 years old underwent sonography froin October 1995 through June 1996. The largest long-axis renal dimension in sagittal, coronal, and prone planes was obtained for each kidney. Data were analyzed separately for each kidney to determine the individual variation of renal length. RESULTS: The correlation between maximum renal length on coronal, sagittal, and prone sonograms was greater than .95 for both right and left kidneys. The coronal plane yielded the largest measured renal length and the prone view, the smallest. The median of the absolute value of the differences between individual renal lengths as measured on sonograms in the different imaging planes was 2-3 mm for both left and right kidneys (mean difference, left kidney = 3.34-3.62 mm; mean difference, right kidney = 3.22-3.68 mm). CONCLUSION: The coronal and sagittal views yield the longest measurements and prone views, the shortest. Therefore, initial measurements should be made in coronal or sagittal planes. Prone views should be reserved for situations in which the suspicion exists that the kidney was foreshortened on other views. Reference standards done in a particular plane should be applicable in most situations regardless of the patient position necessary to obtain optimum length.