LTB4 is present in exudative pleural effusions and contributes actively to neutrophil recruitment in the inflamed pleural space

The pleural space is a virtual compartment between the lung and chest wall that becomes filled with fluid and inflammatory cells during a variety of respiratory diseases. Here, we study the potential role of the eicosanoid metabolite leukotriene B4 (LTB4) in disparate diseases leading to acute (pneumonia) or chronic (tuberculosis, cancer) inflammation of the pleural space. LTB4 concentrations were significantly higher in pleural fluid due to pneumonia, tuberculosis and cancer with respect to congestive heart failure and correlated with neutrophil elastase, which is used as an indication of state of activation of neutrophils in the pleural space. Moreover, pleural LTB4 was biologically active, as an anti-LTB4 antibody partially neutralized the chemotactic activity of parapneumonic, tuberculous and cancer effusions. Macrophages, neutrophils, lymphocytes, mesothelial cells and cancer cells all expressed mRNA for 5-lipoxygenase, the enzyme that initiates leukotriene synthesis leading to the production of LTB4, in exudative pleural effusions. Upon stimulation in transudative pleural effusions, pleural macrophages produced, in a time-dependent fashion, a significantly higher concentration of LTB4 than mesothelial cells. These studies demonstrate that different cell types are capable of producing LTB4 in the inflamed pleural space and that this mediator may play a crucial role in the recruitment of neutrophils into the pleural space.     

Neuropathogenesis of Chimeric Simian/Human Immunodeficiency Virus infection In Pig-tailed and Rhesus Macaques

We recently reported that a chimeric simian/human immunodeficiency virus (SHIV_KU-1) developed in our laboratory caused progressive depletion of CD4⁺T lymphocytes and AIDS within 6 months of inoculation into pig-tailed macaques (M.nemestrina). None of the pig-tailed macaques showed productive SHIV infection in the central nervous system (CNS). In this report, we show that by further passage of the pathogenic virus in rhesus macaques [M. mulatta], we have derived a new strain of SHIV (SHIV_KU-2) that has caused AIDS and productive CNS infection in 3 of 5 rhesus macaques infected with the virus. Productive replication of SHIV in the CNS was clearly shown by high infectivity titers and p27 protein levels in brain homogenates, and in 2 of the 3 rhesus macaques this was associated with disseminated, nodular, demyelinating lesions, including focal multinucleated giant cell reaction, largely confined to the white matter. These findings were reminiscent of HIV-1 associated neurological disease, and our immunohistochemical and in situ hybridization data indicated that the neuropathological lesions were associated with the presence of SHIV-specific viral antigens and nucleic acid respectively. However, the concomitant reactivation of opportunistic infections in these macaques suggested that such pathogens may have influenced the replication of SHIV in the CNS, or modified the neuropathological sequelae of SHIV infection in the rhesus species, but not in pig-tailed macaques. Our findings in the two species of macaques highlight the complexities of lentiviral neuropathogenesis, the precise mechanisms of which are still elusive.     

Role of endogenous cannabinoids in synaptic signaling

Research of cannabinoid actions was boosted in the 1990s by remarkable discoveries including identification of endogenous compounds with cannabimimetic activity (endocannabinoids) and the cloning of their molecular targets, the CB1 and CB2 receptors. Although the existence of an endogenous cannabinoid signaling system has been established for a decade, its physiological roles have just begun to unfold. In addition, the behavioral effects of exogenous cannabinoids such as delta-9-tetrahydrocannabinol, the major active compound of hashish and marijuana, await explanation at the cellular and network levels. Recent physiological, pharmacological, and high-resolution anatomical studies provided evidence that the major physiological effect of cannabinoids is the regulation of neurotransmitter release via activation of presynaptic CB1 receptors located on distinct types of axon terminals throughout the brain. Subsequent discoveries shed light on the functional consequences of this localization by demonstrating the involvement of endocannabinoids in retrograde signaling at GABAergic and glutamatergic synapses. In this review, we aim to synthesize recent progress in our understanding of the physiological roles of endocannabinoids in the brain. First, the synthetic pathways of endocannabinoids are discussed, along with the putative mechanisms of their release, uptake, and degradation. The fine-grain anatomical distribution of the neuronal cannabinoid receptor CB1 is described in most brain areas, emphasizing its general presynaptic localization and role in controlling neurotransmitter release. Finally, the possible functions of endocannabinoids as retrograde synaptic signal molecules are discussed in relation to synaptic plasticity and network activity patterns.     

Ser80Ile mutation and a concurrent Pro25Leu variant of the <Emphasis Type="Italic">VHL</Emphasis> gene in an extended Hungarian von Hippel-Lindau family

Von Hippel-Lindau disease (VHL) is a rare autosomal dominant disease characterized by development of cystic and tumorous lesions at multiple sites, including the brain, spinal cord, kidneys, adrenals, pancreas, epididymis and eyes. The clinical phenotype results from molecular abnormalities of the VHL tumor suppressor gene, mapped to human chromosome 3p25-26. The VHL gene encodes two functionally active VHL proteins due to the presence of two translational initiation sites separated by 53 codons. The majority of disease-causing mutations have been detected downstream of the second translational initiation site, but there are conflicting data as to whether few mutations located in the first 53 codons, such as the Pro25Leu could have a pathogenic role. In this paper we report a large Hungarian VHL type 2 family consisting of 32 members in whom a disease-causing AGT80AAT (Ser80Ile) c.239G>A, p.Ser80Ile mutation, but not the concurrent CCT25CTT (Pro25Leu) c.74C>T, p.Pro25Leu variant co-segregated with the disease. To our knowledge, the Ser80Ile mutation has not been previously described in VHL type 2 patients with high risk of pheochromocytoma and renal cell cancer. Therefore, this finding represents a novel genotype-phenotype association and VHL kindreds with Ser80Ile mutation will require careful surveillance for pheochromocytoma. We concluded that the Pro25Leu variant is a rare, neutral variant, but the presence such a rare gene variant may make genetic counseling difficult.     

Low extracellular magnesium induces epileptiform activity and spreading depression in rat hippocampal slices

The effect of low extracellular Mg2+ concentration ([Mg2+]o) on neuronal activity was studied in rat hippocampal slices. After 20-40 min of perfusion with Mg2+-free medium, when [Mg2+]o declined to approximately 0.1-0.4 mM, spontaneous field potentials developed in the CA1 and CA3 regions, but not in the dentate gyrus. In the CA3 pyramidal cell layer, these potentials consisted of repetitive (0.3-0.5 Hz), 40- to 120-ms-long positive deflections (2-5 mV) with superimposed population spikes. In the stratum (str.) pyramidale of the CA1 region, positive-negative deflections (less than 3 mV) lasting for 30-80 ms were observed, which occurred with a frequency of 0.3-0.5 Hz. In some cases, longer lasting and rapidly recurring events were also observed. In CA3 pyramidal cells, the intracellular correlates of the field potential transients were 20- to 30-mV paroxysmal depolarization shifts (PDS) with superimposed bursts of action potentials, followed by large (greater than 10 mV), 500- to 1,200-ms-long afterhyperpolarizations (AHP). In contrast, pyramidal neurons of the CA1 area did not show PDSs; instead, sequences of excitatory postsynaptic potentials (EPSPs)/inhibitory postsynaptic potentials (IPSPs) accompanied the transient field potential changes. Occasionally, spontaneous EPSPs/IPSPs, occurring with high frequencies, could also be observed in CA1 without any field potential transients. In both hippocampal regions, the epileptiform activity evolved without significant alterations in the resting membrane potential (RMP) and input resistance (RN) of the neurons, although a 2- to 5-mV reduction in action potential threshold was noted. The spontaneous activity in Mg2+-free medium was readily suppressed by raising the extracellular Ca2+ concentration ([Ca2+]o) from 1.6 to 3.6 mM. The perfusion of 10-30 microns DL-2-amino-5-phosphonovaleric acid (2-APV), an antagonist for the glutamate receptors of the N-methyl-D-aspartate (NMDA) type, also attenuated or reversibly blocked the spontaneous activity. Surgical isolation of area CA1 from CA3 ceased the occurrence of the transients in CA1 but not in CA3. The synaptic input/output curves were shifted to the left in the absence of [Mg2+]o. Threshold intensity for eliciting population spikes was 50-75% of that in normal medium. Paired-pulse facilitation was still present near threshold, but was reduced at higher stimulus intensities. Decreases in [Ca2+]o, produced by repetitive stimulation (20-Hz/5-10 s) of the Schaffer collateral/commissural pathway and monitored with ion-selective microelectrodes in the CA1 region, were enhanced in Mg2+-free medium.(ABSTRACT TRUNCATED AT 400 WORDS)     

Proteins in the cell wall and membrane of Cryptococcus neoformans stimulate lymphocytes from both adults and fetal cord blood to proliferate.

Cryptococcus neoformans is an encapsulated yeast that infects patients who have defective cell-mediated immunity, including AIDS, but rarely infects individuals who have intact cell-mediated immunity. Studies of the immune response to C. neoformans have been hampered by a paucity of defined T-lymphocyte antigens, and hence, the understanding of the T-cell response is incomplete. The goal of this study was to separate C. neoformans into its component parts, determine whether those components stimulate lymphocyte proliferation, perform preliminary characterization of the proteins, and establish the potential mechanism of lymphocyte proliferation. The lymphocyte response to fungal culture medium, whole organisms, disrupted organisms, and the yeast intracellular fraction or cell wall and membrane was studied by determining thymidine incorporation and by determining the number of lymphocytes at various times after stimulation. The cell wall and membrane of C. neoformans stimulated lymphocyte proliferation, while the intracellular fraction and culture filtrate did not. The optimal response occurred on day 7 of incubation, with 4 x 10(5) peripheral blood mononuclear cells per well and with 13 microg of cryptococcal protein per ml. The number of lymphocytes increased with time in culture, indicating that thymidine incorporation was accompanied by proliferation. Proteinase K treatment of the cell wall and membrane abrogated lymphocyte proliferation, indicating that the molecule was a protein. [35S]methionine labeling, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and fluorography were performed to analyze the proteins contained in the cell wall and membrane, intracellular fraction, and culture filtrate. At least 18 discrete bands were resolved from the cell wall and membrane. Since a large percentage of healthy adults responded to the cryptococcal cell wall and membrane, a mitogenic effect was investigated by testing proliferation of fetal cord blood lymphocytes. The percentage of fetal samples that proliferated in response to the cell wall and membrane was similar to the percentage of fetal samples that proliferated in response to Staphylococcus enterotoxin B, a microbial mitogen. Thus, a protein in the cell wall and membrane of C. neoformans is a potent stimulant of lymphocyte proliferation and has mitogenic properties, which may have important implications for cell-mediated immunity to C. neoformans.     

Follicle stimulating hormone measured in unextracted urine throughout the menstrual cycle correlates with age and ovarian reserve

BACKGROUND: A method was previously described to measure FSH reliably in unextracted urine. The aim of the current study was to establish the course of FSH measured in urine throughout the cycle. METHOD: Daily urinary FSH (uFSH) concentrations were determined in 14 regularly menstruating volunteers aged 23-39 years during one complete menstrual cycle. RESULTS: In each subject, mean daily uFSH measured in urine, as gold standard for FSH tone, correlated significantly with FSH in early follicular phase fixed to menstruation on cycle day 3 (r = 0.75, P = 0.002), or fixed to ovulation 9 days before the pre-ovulatory FSH surge (r = 0.87, P = 0.0001), or when selected as being the highest follicular phase value (r = 0.91, P = 0.0001). Age correlated significantly with mean daily uFSH (r = 0.67, P = 0.009), highest follicular phase uFSH (r = 0.60, P = 0.024), uFSH on cycle day 3 (r = 0.80, P = 0.0006), and uFSH 9 days before FSH surge (r = 0.65, P = 0.0016). The uFSH was also measured on cycle day 3 in 104 IVF patients in a cycle prior to pituitary down-regulation. The uFSH correlated significantly with numbers of follicles (P = 0.02) and oocytes (P = 0.024). CONCLUSION: It is concluded that cycle day 3 uFSH is a good reflection of the mean uFSH of the complete cycle, and there is a highly significant correlation between uFSH and age and ovarian reserve. Measurement of FSH in urine on cycle day 3 seems to be a reliable and non-invasive tool for determining ovarian reserve in IVF.     

Galaxy: a platform for interactive large-scale genome analysis

Accessing and analyzing the exponentially expanding genomic sequence and functional data pose a challenge for biomedical researchers. Here we describe an interactive system, Galaxy, that combines the power of existing genome annotation databases with a simple Web portal to enable users to search remote resources, combine data from independent queries, and visualize the results. The heart of Galaxy is a flexible history system that stores the queries from each user; performs operations such as intersections, unions, and subtractions; and links to other computational tools. Galaxy can be accessed at http://g2.bx.psu.edu.     

Fine-needle aspiration of cystic lesions of the kidney. Morphologic spectrum and diagnostic problems in 41 cases

Although imaging studies show the nature of most cystic lesions of the kidney (RCs), many RCs require fine-needle aspiration (FNA) for accurate diagnosis. Interpretation of the FNAs remains challenging. The FNA specimens of 41 RCs were reviewed and correlated with imaging studies. Final diagnoses for 30 cytologically benign lesions were simple cyst (28), acquired cystic kidney (1), and cystic renal carcinoma (1). The fluid from the benign cysts displayed macrophages, epithelial cells from the cyst lining, tubular cells, neutrophils, and Liesegang rings. Fluid from the acquired cystic kidney and the cystic renal cell carcinoma showed features similar to those of the benign cysts. The 9 cases with "suspicious" cytology included 5 complex cystic lesions displaying rare but atypical epithelial cell clusters, 3 low-grade renal cell carcinomas with many mildly atypical papillary clusters of epithelial cells, and 1 simple benign cyst with many tubular cells. The 2 cytologically malignant lesions were cystic renal cell carcinomas with abundant tumor cells with partially clear cytoplasm and atypical nuclei admixed with abundant macrophages and lymphocytes; 1 case developed in a kidney with acquired cystic disease. Simple cysts remain the most frequently aspirated RCs, but complex cystic lesions are increasingly recognized. Since many RCs are composed of independent loculi, a nonrepresentative sample is a potential problem, and cytologic-radiologic correlation becomes mandatory. The "suspicious" patterns identified in this study should serve as diagnostic guidelines and set the foundation for future validation.     

Influence of Dialysable Transfer Factor on IgE Concentrations in Patients with Atopic Dermatitis

Dialysable transfer factor (TF) was given in 10 paediatric patients with severe atopic dermatitis (AD). Ten patients with AD, matched for age and severity of disease, served as controls.
Prior to the therapy with TF and at weekly intervals thereafter, T- and B-cells in the blood, PHA-stimulation, total IgE and specific IgE antibodies to inhalant and food antigens were determined. Therapy with TF was followed by IgE depression in 8/10 patients and was most pronounced in three patients with initially high levels. Some decrease of IgE levels was seen in four controls also, none of them, however, fell to normal levels as was seen in two of the treated patients.
Specific IgE levels decreased slightly, but always remained within the pathological range. T-cell counts in the blood increased in 2/10 cases as well as PHA-stimulation. B-cell counts remained within normal limits. Clinical improvement was seen in one patient, five improved slightly and four remained unchanged.
Our results indicate, that transfer factor can lower total IgE levels in cases with atopic dermatis. The effect is most marked in patients with high total IgE levels. Skin involvement, however, does not closely follow in vitro findings.