Sequence and structure relatedness of matrix protein of human respiratory syncytial virus with matrix proteins of other negative-sense RNA viruses

Matrix proteins of viruses within the order Mononegavirales have similar functions and play important roles in virus assembly. Protein sequence alignment, phylogenetic tree derivation, hydropathy profiles and secondary structure prediction were performed on selected matrix protein sequences, using human respiratory syncytial virus matrix protein as the reference. No general conservation of primary, secondary or tertiary structure was found, except for a broad similarity in the hydropathy pattern correlating with the fact that all the proteins studied are membrane-associated. Interestingly, the matrix proteins of Ebola virus and human respiratory syncytial virus shared secondary structure homology.

Multiple heparin binding domains of respiratory syncytial virus G mediate binding to mammalian cells

Respiratory syncytial virus (RSV) G glycoprotein mediates cell attachment through surface glycosaminoglycans (GAGs). Feldman et al. [10] suggested that specific basic amino acids in residues 184-198 of G defined a critical heparin binding domain (HBD). To further define the G HBD we made a series of truncated G proteins expressed in Escherichia coli. G88 (G residues 143-231), bound to HEp-2 cells in a dose dependent manner and binding was inhibited >99% with heparin. Cell binding of G88 was unaltered by alanine substitution mutagenesis of all basic amino acids in Feldman's region 184-198. A G88 variant truncated beyond residue 198, G58, and G58 fully alanine substituted in the region 184-198, G58A6, bound to HEp-2 cells about half as well and 100-fold less well than G88, respectively. G88 and all alanine substitution mutants of G88 inhibited RSV plaque formation by 50% (ID(50)) at concentrations of approximately 50 nM; the ID(50) of G58 was approximately 425 nM while G58A6 had an ID(50) >1600 nM. These data show that the G HBD includes as much as residues 187-231, that there is redundancy beyond the previously described HBD, and that the cell-binding and virus infectivity-blocking functions of these recombinant G proteins were closely linked and required at least one HBD.

Association of matrix protein of respiratory syncytial virus with the host cell membrane of infected cells

The matrix protein of paramyxoviruses plays an important role in virus assembly through its interactions with cell membrane, virus envelope and virus nucleocapsid. In the present study, we investigated the possible association of respiratory syncytial virus (RSV) matrix (M) protein with the plasma membrane of infected cells. Using confocal microscopy we found that M was present at the cytoplasmic side of the plasma membrane. We used flotation gradients to purify membranes from RSV infected cells and treated them with cold Triton X-100 to obtain lipid rafts in the insoluble fraction. Western blot of the lipid raft fraction with specific antibodies showed that it contained M, as well as G (attachment) and N (nucleocapsid) proteins. We also found that RSV purified on sucrose gradients contained lipid raft markers. Together, our data suggest that RSV uses lipid rafts for assembly and budding.

The matrix protein of Human respiratory syncytial virus localises to the nucleus of infected cells and inhibits transcription

We studied the kinetics of localisation of matrix (M) protein of Human respiratory syncytial virus (RSV) in infected cells. M protein was detected in the nucleus early in infection, by confocal microscopy and by immunoblotting of nuclear fractions. We next tested the possibility that M protein may be involved in inhibition of host cell transcription. Nuclear extracts from RSV infected cells had less transcriptional activity in vitro when compared to nuclear extracts from mock infected cells. In addition, nuclear extracts from RSV infected cells inhibited the transcriptional activity of nuclear extracts from mock infected cells, suggesting that an inhibitory activity was transferred with nuclear extracts from RSV infected cells. Our data suggest that M protein may play a role early in the infection by inhibiting host cell transcription.

Forecasting the future of HIV epidemics: the impact of antiretroviral therapies & imperfect vaccines

Mathematical models can be used as health policy tools and predictive tools. Here we review how mathematical models have been used both to predict the consequences of specific epidemic control strategies and to design epidemic control strategies. We review how models have been used to evaluate the potential impact on HIV epidemics of (i) combination antiretroviral therapies (ART) and (ii) imperfect vaccines. In particular, we discuss how models have been used to predict the potential effect of ART on incidence rates, and to predict the evolution of an epidemic of drug-resistant HIV. We also discuss, in detail, how mathematical models have been used to evaluate the potential impact of prophylactic, live-attenuated and therapeutic HIV vaccines. We show how HIV vaccine models can be used to evaluate the epidemic-level impact of vaccine efficacy, waning in vaccine-induced immunity, vaccination coverage level, and changes (increases or decreases) in risky behavior. We also discuss how mathematical models can be used to determine the levels of cross-immunity that vaccines will need to attain if they are to be used to control HIV epidemics in countries where more than one subtype is being transmitted.

Benefit from endoscopic sinus surgery

Benefit and satisfaction following endoscopic sinus surgery were assessed using the Glasgow Benefit Inventory (GBI) and a validated outcome satisfaction score. In total, 140 patients were invited to participate; 101 (71%) responded. ESS produces significant benefit as assessed by the GBI and satisfaction, and the benefit compares favourably with other otorhinolaryngological procedures. Greatest benefit was derived by patients undergoing surgery for polyp disease. Patients whose cardinal preoperative symptom was nasal obstruction or headache tended to report higher benefit. Co-existent asthma, allergic rhinitis or aspirin intolerance appeared not to result in a significant decrease in benefit after surgery, except in patients with non-polyp disease, who also have both aspirin intolerance and asthma. Also, for non-polyp disease, postoperative medication with nasal steroids or antihistamines does not appear to influence benefit.

Ethical considerations and training recommendations for philosophical counseling

Philosophical counseling is a diverse and burgeoning type of mental health service delivery. Despite competing approaches to theory and practice, the field has largely strayed from an ethical critique of its methodology and counselor training requirements. This article outlines several ethical considerations and training recommendations that are proposed to bolster the quality and effectiveness of philosophical practice. As philosophical counseling gains increasing recognition in North America, recently established national organizations in philosophical practice may profit from revisiting their interim codes for professional conduct. Proposed training suggestions for counselor preparation my further assist institutions and board-regulated agencies in establishing competent and acceptable standards of client care.

Elevated fibrinogen in the healthy male relatives of patients with severe, premature coronary artery disease

AIMS

To assess the possible role of certain coagulation factors and associated genetic polymorphisms in families in which coronary disease has occurred prematurely.

METHODS AND RESULTS

One hundred and eighty-five healthy male relatives aged 65 or less were recruited following the identification of 125 patients with confirmed, premature coronary artery disease and compared to a control group of 185 healthy, age-matched volunteers. None of the control subjects had a personal or family history of coronary artery disease. The relatives and controls were similar in terms of conventional coronary artery disease risk factors. Fibrinogen levels were elevated in relatives compared with controls and remained higher after adjustment for significant correlates, 3.0 g.l(-1) (2.9-3.1) vs 2.8 g.l(-1) (2.8-2.9),P =0.004. Factor VII coagulant activity and von Willebrand factor antigen did not differ between the groups nor were there any differences in genotype frequency for the fibrinogen beta-455 G/A polymorphism or the factor VII promoter deletion/insertion and Arg-Gln coding polymorphisms.

CONCLUSIONS

A significant increase in fibrinogen levels was demonstrated in the healthy, male, first-degree relatives of patients with severe coronary artery disease. Fibrinogen may be of particular importance in subjects who, other than their family history, appear to be at low risk in terms of conventional coronary artery disease risk factors.

Infectivity of wild-type and deleted proviral SIV DNA

Live attenuated lentiviruses are potentially effective candidate HIV vaccines; however, delivery of these viruses in the field would be problematic. Delivery of attenuated lentiviruses as proviral DNA would be a simple means of immunization, but the efficiency of this method of delivery is not known. In this study, macaques were readily infected following inoculation of plasmid DNA encoding proviral simian immunodeficiency virus (SIVmac239), whether given i.m. (300 microg) or epidermally (15 microg), with all four animals succumbing to AIDS at a mean of 26 weeks following inoculation. Using a human skin explant model, we found that the 50% infectious dose (ID50) of proviral SIV or HIV-1 plasmid may be as low as 1 microg when delivered to skin by gold particle bombardment using a gene gun. An infectious proviral clone of SIV mac239 with a 105 bp deletion in the 3' nef/LTR overlap region was engineered (SIVsbbc delta3), analogous to the initial common nef/LTR deletion in HIV-1 strains isolated from an Australian cohort of long-term slow-progressors. Two further macaques were also readily infected with SIVsbbc delta3 after i.m. injection of 300 microg of highly purified plasmid DNA. Unexpectedly, in one macaque inoculated with SIVsbbc delta3 DNA, SIV strains isolated three to six weeks after infection had completely repaired the nef/LTR deletion with wild-type sequence, and eventually progressed to AIDS. The mechanism used to rebuild this deletion with wild-type sequence, presumably derived from an intact 5' LTR, is unclear, but possibilities include RNA read-through errors from the plasmid DNA and recombination with residual plasmid DNA at the inoculation site.

Respiratory syncytial virus matrix protein associates with nucleocapsids in infected cells

Little is known about the functions of the matrix (M) protein of respiratory syncytial virus (RSV). By analogy with other negative-strand RNA viruses, the M protein should inhibit the viral polymerase prior to packaging and facilitate virion assembly. In this study, localization of the RSV M protein in infected cells and its association with the RSV nucleocapsid complex was investigated. RSV-infected cells were shown to contain characteristic cytoplasmic inclusions. Further analysis showed that these inclusions were localization sites of the M protein as well as the N, P, L and M2-1 proteins described previously. The M protein co-purified with viral ribonucleoproteins (RNPs) from RSV-infected cells. The transcriptase activity of purified RNPs was enhanced by treatment with antibodies to the M protein in a dose-dependent manner. These data suggest that the M protein is associated with RSV nucleocapsids and, like the matrix proteins of other negative-strand RNA viruses, can inhibit virus transcription.

No association between CHRNA7 microsatellite markers and attention-deficit hyperactivity disorder

Attention-deficit hyperactivity disorder (ADHD) is a highly heritable, common psychiatric disorder of childhood that probably involves several genes. There are several lines of evidence suggesting that the nicotinic system may be functionally significant in ADHD. First, nicotine promotes the release of dopamine and has been shown to improve attention in adults with ADHD, smokers, and nonsmokers. Second, ADHD is a significant risk factor for early initiation of cigarette smoking in children and maternal cigarette smoking appears to be a risk factor for ADHD. Finally, animal studies in rats and monkeys also suggest that nicotine may be involved in attentional systems and locomotor activity. The nicotinic system has previously been studied in schizophrenia where the neuronal nicotinic acetylcholine receptor alpha 7 subunit gene (CHRNA7) has been implicated in decreased P50 inhibition and attentional disturbances in patients with schizophrenia and in many of their nonschizophrenic relatives. Three known microsatellite markers (D15S165, D15S1043, and D15S1360) near the nicotinic acetylcholine alpha 7 receptor gene, CHRNA7, were studied in 206 ADHD parent-proband trios of children aged 5-16 with ADHD according to DSM-IV criteria. Children with known major medical or psychiatric conditions or mental retardation (IQ < 70) were excluded from the study. Markers D15S165 and D15S1360 were in linkage disequilibrium. The extended Transmission Disequilibrium Test analyses demonstrated no evidence that variation at the microsatellite markers D15S1360, D15S1043, and D15S165 influences susceptibility to ADHD. However, it remains possible that the CHRNA7 gene and other nicotinic system genes may be involved in conferring susceptibility to ADHD.

The history of modern psychiatry in India, 1858-1947

This article presents an introduction to the history of Indian psychiatry. It suggests that this history can be divided into four main periods, 1795 to 1857, 1858 to 1914, 1914 to 1947 and 1947 to the present day. The focus of the piece is on the periods 1858-1914 and 1914-1947, as it traces the main trends and developments of the colonial era and argues that the foundations of modern psychiatry in India were laid down in the period of British rule. A brief consideration of the post-Independence period suggests that the patterns established in the years of British rule have continued to influence the psychiatric system of modern India. Research for these conclusions is based on extensive archival work in Indian mental health institutions and in Indian records offices, as well as work conducted at the National Library of Scotland in Edinburgh and at the India Office Library, the Wellcome Institute Library and the London School of Hygiene and Tropical Medicine.

Vaccination with attenuated simian immunodeficiency virus by DNA inoculation

Delivering attenuated lentivirus vaccines as proviral DNA would be simple and inexpensive. Inoculation of macaques with wild-type simian immunodeficiency virus strain mac239 (SIV(mac239)) DNA or SIV(mac239) DNA containing a single deletion in the 3' nef-long terminal repeat overlap region (nef/LTR) led to sustained SIV infections and AIDS. Injection of SIV(mac239) DNA containing identical deletions in both the 5' LTR and 3' nef/LTR resulted in attenuated SIV infections and substantial protection against subsequent mucosal SIV(mac251) challenge.

Streptococcus pneumoniae PstS production is phosphate responsive and enhanced during growth in the murine peritoneal cavity

Differential display-PCR (DDPCR) was used to identify a Streptococcus pneumoniae gene with enhanced transcription during growth in the murine peritoneal cavity. Northern dot blot analysis and comparative densitometry confirmed a 1.8-fold increase in expression of the encoded sequence following murine peritoneal culture (MPC) versus laboratory culture or control culture (CC). Sequencing and basic local alignment search tool analysis identified the DDPCR fragment as pstS, the phosphate-binding protein of a high-affinity phosphate uptake system. PCR amplification of the complete pstS gene followed by restriction analysis and sequencing suggests a high level of conservation between strains and serotypes. Quantitative immunodot blotting using antiserum to recombinant PstS (rPstS) demonstrated an approximately twofold increase in PstS production during MPC from that during CCs, a finding consistent with the low levels of phosphate observed in the peritoneum. Moreover, immunodot blot and Northern analysis demonstrated phosphate-dependent production of PstS in six of seven strains examined. These results identify pstS expression as responsive to the MPC environment and extracellular phosphate concentrations. Presently, it remains unclear if phosphate concentrations in vivo contribute to the regulation of pstS. Finally, polyclonal antiserum to rPstS did not inhibit growth of the pneumococcus in vitro, suggesting that antibodies do not block phosphate uptake; moreover, vaccination of mice with rPstS did not protect against intraperitoneal challenge as assessed by the 50% lethal dose.

Time-related decay of the benefits of biofeedback therapy

Although immediate results are good to excellent in great majority of patients who undergo biofeedback treatment (BFT) for chronic constipation and fecal incontinence, they tend to loose the benefit over a period of time. The purpose of this study was to evaluate the long-term sustainability of results after successful biofeedback treatment. Two groups of patients who successfully completed BFT at our institution from 1995 to 1997 were created based on the date of completion. The first had a mean follow-up of 35 months and the second group was followed for an average of 12 months. Both groups were questioned as to the presence of constipation and incontinence. The questioning was focused depending on the patient's diagnosis. This information was then compared with the initial BFT results. Overall, all patients were satisfied by the initial BFT results. All patients initially had an excellent or good response to BFT. However, after a mean of 35 months, in the first group, 19 of 22 patients had a near complete regression back to their pre-biofeedback status. In the 14 patients in the second group with mean follow-up of 12 months, 11 had a significant decay in benefits. Only time was a significant factor in the decay of BFT benefits. In conclusion, BFT is highly effective in the treatment of selected patients with complex defecation disorders. Although there is a high initial success rate, there is a clear loss of the immediate benefits over time. Other factors such as dietary habits, pelvic floor exercises, manometry, invasive EMG, and rectal sensation did not correlate with long-term outcomes. The comparison between the two groups reveals a linear model describing the time decay of the benefits of BFT. Based on the linear model, patients may need reevaluation after one year and may benefit from additional BFT.

Seasonal variation in prevalence of antibody to hantaviruses in rodents from southern Argentina

We conducted a small mammal trapping study to investigate temporal variation in prevalence of infection in hantavirus reservoir populations in the Patagonian Andes mountain range, Rio Negro province, Argentina. Rodent blood samples collected in natural and periurban habitats and at the home of an hantavirus pulmonary syndrome (HPS) case patient were analysed by enzyme-linked immunosorbent assay. Organ tissue samples were tested by polymerase chain reaction (PCR) and nucleotide sequence analysis. Eight species of 1032 rodents were captured in 15 551 trap nights, giving an overall trap success of 6.6%. Hantavirus antibody was detected in 30 of 555 Oligoryzomys longicaudatus (reservoir of Andes virus), three of 411 Abrothrix longipilis, and one of 10 Loxodontomys micropus. Antibody prevalences in O. longicaudatus were 13.7% in spring 1996, 59.3% in summer 1996, 2.1% in autumn 1997, 12.4% in winter 1997 and 3.1% in spring 1997. A much higher antibody prevalence (33%) was found during trapping around the residence of an HPS case patient. Higher prevalences were found in older male O. longicaudatus. There was no apparent correlation of antibody prevalence with rodent population density, or of rodent population density or antibody prevalence with numbers of human cases. For an HPS case that occurred in our study area in 1997, we identified the probable rodent reservoir and likely site of exposure by matching the genetic sequences of virus obtained from a rodent and the HPS case patient.