Influenza virus surveillance in Argentina during the 2012 season: antigenic characterization, genetic analysis and antiviral susceptibility.

The activity and circulation of influenza viruses in Argentina was studied during 2012 as part of the Argentinean Surveillance for Influenza and other Respiratory Viruses, in the context of Global Influenza Surveillance. The antigenicity and molecular characteristics of haemagglutinins (HA) of circulating influenza A and B viruses were analysed to assess the emergence of virus variants. Susceptibility to oseltamivir and zanamivir was evaluated by enzymatic assay and results were backed-up by sequencing of the neuraminidase (NA) genes. During the 2012 season, influenza virus circulation in Argentina was detected from weeks 24 to 51. The HA sequences of the studied A(H1N1)pdm09 subtype viruses segregated in a different genetic group compared to those identified during the 2009 pandemic, although they were still closely related antigenically to the vaccine virus A/California/07/2009. The HA sequences of the A(H3N2) viruses analysed fell into the A/Victoria/208/2009 clade, genetic group 3C. A mixed circulation of virus variants belonging to B/Victoria and B/Yamagata lineages was detected, with B/Victoria being dominant. All viruses tested were sensitive to oseltamivir and zanamivir except one. This isolate, an A(H1N1)pdm09 virus possessing the substitution NA-N295S, showed highly reduced inhibition by oseltamivir and reduced inhibition by zanamivir. Virological and epidemiological surveillance remains critical for detection of evolving influenza viruses.

Oseltamivir-resistant influenza A(H1N1)pdm09 virus in Dutch travellers returning from Spain, August 2012.

Two Dutch travellers were infected with oseltamivir-resistant influenza A(H1N1)pdm09 viruses with an H275Y neuraminidase substitution in early August 2012. Both cases were probably infected during separate holidays at the Catalonian coast (Spain). No epidemiological connection between the two cases was found, and neither of them was treated with oseltamivir before specimen collection. Genetic analysis of the neuraminidase gene revealed the presence of previously described permissive mutations that may increase the likelihood of such strains emerging and spreading widely.

Effects of ATP and cell development on the metabolism of high molecular weight aggregates of abnormal proteins in rabbit reticulocytes and cell-free extracts.

Abnormal proteins synthesized in rabbit reticulocytes in response to (i) the lysine analogue aminoethylcysteine and (ii) puromycin, form high molecular weight aggregates prior to degradation. Inhibitors of ATP synthesis partially inhibit catabolism of the aminoethylcysteine-induced abnormal protein; degradation of puromycin peptides synthesized after incubation with 25 micrograms/ml puromycin was not inhibited. Catabolism of the analogue-induced high molecular weight aggregate of abnormal protein in cell-free extracts was markedly stimulated by ATP, whereas proteolysis of the aggregated puromycin-peptides was ATP-independent. The ability of the reticulocytes to degrade the puromycin-peptide aggregates was found to decrease with cellular maturity. It is suggested that the energy-dependency for proteolysis is in some way related to the chain length of the abnormal protein synthesized.

HIV/SIV glycoproteins: structure-function relationships.

The various functions of human (HIV) and simian (SIV) immunodeficiency virus glycoproteins are similar, so it may be assumed that the overall structure of the folded proteins will be maintained. To preserve structure there must be constraints on sequence variation. The majority of mutations tolerated will be involved in immune escape but changes at some positions are known to have direct effects on glycoprotein expression and function. This allows the virus to change its phenotype and escape immune pressure. These properties will influence the fitness of the virus to infect and replicate in potential hosts. A better understanding of the structure-function relationships of HIV/SIV glycoproteins will assist in the development of vaccines and antivirals. Here, we identify similarities and differences between HIV-1 subtypes and HIV/SIV types that may be relevant to the phenotypes of the various groups. The results are discussed in relation to what is known of domain-function associations for HIV/SIV glycoproteins.

Expression of HIV-1 in the cerebrospinal fluid detected by the polymerase chain reaction and its correlation with central nervous system disease.

The polymerase chain reaction (PCR) was used to detect HIV-1 sequences (gag, pol, and env) in the cerebrospinal fluid (CSF) and serum samples from 53 HIV-1-positive patients and the results correlated with clinical evidence of neurological disease. Twenty-three out of 24 patients with neurological disease had HIV-1-specific sequences in CSF compared with four out of 20 asymptomatic patients who had no evidence of neurological involvement. The detection of HIV RNA sequences by PCR in the CSF of HIV-positive patients may provide early, rapid and direct evidence of neurological involvement in asymptomatic subjects.

An efficient method for the rescue and analysis of functional HIV-1 env genes: evidence for recombination in the vicinity of the tat/rev splice site.

OBJECTIVE: To establish a robust procedure for the isolation and characterization of full-length expression-competent HIV-1 env genes directly from patient samples. DESIGN: HIV exists as a quasispecies which can be disturbed by in vitro culture, in which numerous members of the population are likely to be defective due to the high error rate of the viral reverse transcriptase. Defective viruses are unlikely to play a dominant role in disease progression. Since env gene translation products play major roles in the initiation and spread of infection we need to study genes with open reading frames. METHODS: A nested polymerase chain reaction (PCR) approach has been used to rescue intact (2.6 kb) env genes, which are cloned into a T7-promoter-containing vector. Expression of gp160 in CV-1 cells is detected by Western blot. Expression-competent clones are sequenced and resulting sequences used for phylogenetic studies. Translation products are analysed in relation to the known immunogenic structure of gp160. RESULTS: From random patient samples collected in London clinics, only HIV-1 subtype B was found. Two of the samples contained viruses with an additional pair of cysteine residues in their V1 regions. For samples collected in Uganda, HIV-1 subtypes A, D and an A/D recombinant were recovered. CONCLUSION: An effective procedure is described for the isolation of HIV-1 env genes directly from patient samples, which has worked for A, B and D subtypes to date. The PCR primers can be utilized with other subtypes with the possible exception of subtype O viruses. Phylogenetic analyses revealed the potential importance of a G/C-rich region near the tat/rev splice site as a site of recombination. The sequences and translation products generated may be more relevant to disease progression in vivo and vaccine formulations than those obtained from viruses selected in long-term culture.

Psychiatric education: state of the art, 1976.

The authors describe an extraordinary review of 527 programs in 205 institutions conducted by the Psychiatry Education Branch of NIMH. Each institution was evaluated by 2 site visitors, whose findings were reviewed by a group of 12 special consultants. These consultants voted on approval of grant applications and assigned priorities to those which were approved. Direct results of the review included approval of 69% of the programs, increased support of programs in medical student education, consultation-liaison psychiatry, and psychiatric investigation, but a decrease in the total number of institutions supported. Indirect results were the encouragement of self-evaluation in each program reviewed, the valuable exchange of ideas among the educators involved in the review process, and implications for future reviews. The authors, who believe that psychiatric education is in good health, discuss the findings of this review in terms of the future of the field.

Characteristics of psychiatric residency programs and quality of education.

As part of the fiscal year 1975 NIMH review of all psychiatric education grants, 144 basic residency training programs were thoroughly examined. In order to generate hypotheses about factors related to quality, the authors divided these grants into those given high priority rankings, those ranked in the middle, and those disapproved. Faculty and trainee characteristics, aspects of the service system, and organizational, educational, and evaluation factors were strongly related to quality. In general, good programs had a primary theoretical orientation with a tolerance for diversity, were not administratively responsible for community mental health centers but had strong community service ties, and tended to be in university settings. The authors point out the need to determine psychiatry's role vis-à-vis primary care and to develop a clear understanding of the place psychiatry will have in the health and mental health systems.

Subcellular distribution of abnormal proteins in rabbit reticulocytes. Effects of cellular maturation, phenylhydrazine and inhibitors of ATP synthesis.

Inhibitors of ATP synthesis (cyanide, dinitrophenol, fluoride) inhibited proteolysis of pulse-labelled abnormal proteins in rabbit reticulocytes and caused an accumulation of the aberrant polypeptides in the cell debris fraction in a manner analogous to phenylhydrazine-induced Heinz bodies. When the reticulocytes were separated into age-groups by sedimentation through discontinuous gradients of bovine serum albumin, the ability of the cells to degrade puromycin peptides decreased with increasing cellular maturity and, in the more mature cells, up to 40% of the labelled abnormal polypeptide remained associated with the cell debris fraction at the end of the chase period. It is suggested that the association of the abnormal polypeptide with the cell debris fraction is a consequence of a maturation-induced loss, or an inhibitor-induced inactivation of the cellular proteolytic activity.

World War I may have allowed the emergence of "Spanish" influenza.

The 1918 influenza pandemic caused 40 million deaths, and so dwarfed in mortality and morbidity the preceding pandemic of 1889 and the 1957 and 1968 pandemics. In retrospect, much can be learnt about the source, the possible subterranean spread of virus, and the genetic basis of virulence. The World Health Organization has urged every nation to prepare a pandemic plan for the first global outbreak of the 21st century. We present an appraisal of epidemiological and mortality evidence of early outbreaks of respiratory disease in France and the UK in the years 1915 to 1917. Certain of these earlier focal outbreaks--called epidemic bronchitis rather than influenza--occurred during the winter months when influenza was known to be in circulation, and presented with a particular heliotrope cyanosis that was so prominent in the clinical diagnosis in the world pandemic outbreak of 1918-1919 (the Great Pandemic). The outbreaks in army camps at Etaples in France and Aldershot in the UK in 1916-1917 caused very high mortality in 25-35 year olds. Increased deaths from bronchopneumonia and influenza were also recorded in England. We deduce that early focal outbreaks of influenza-like disease occurred in Europe and on the balance of probability the Great Pandemic was not initiated in Spain in 1918 but in another European country in the winter of 1916 or 1917. We suggest that the pandemic had its origins on the Western Front, and that World War I was a contributor.

Sequence analysis of the equine H7 influenza virus haemagglutinin gene.

The nucleotide sequences of ten haemagglutinin genes of representative H7N7 equine influenza viruses isolated between 1956 and 1977 have been determined by primer extension sequencing. Their nucleotide and deduced amino acid sequences demonstrate a high degree of homology. These equine viruses can be divided into two distinct subgroups, the prototype-like, and a group comprising the early American isolates and the remaining equine viruses. The equine H7 haemagglutinins form a quite distinct group compared to H7 haemagglutinins isolated from other species. Each of these equine H7 haemagglutinins possess a tetrabasic amino acid cleavage site separating the HA1 and HA2 domains but, in addition, all ten contain a nine amino acid insertion prior to the tetrabasic sequence. The haemagglutinin glycoproteins of all ten viruses are capable of cleavage activation in virus infected primary chicken embryo fibroblast cells.

Maintenance of glycoprotein-determined phenotype in an HIV type 1 (pNL43) env gene-cassetting system.

Here we report the construction and use of a full-length env gene-cassetting system, C2, based on the HIV-1 infectious molecular clone NL43. C2 produces virus with the same phenotype as NL43 but with 2-fold lower growth kinetics. The latter probably relates to alteration in the vpu and/or nef genes. C2-env chimeras of macrophage-tropic and T cell-tropic laboratory strains and primary HIV-1 isolates retain the glycoprotein-determined phenotypes of their parent viruses. The cassette will assist studies of HIV-1 pathogenesis.

Analysis of full-length HIV type 1 env genes indicates differences between the virus infecting T cells and dendritic cells in peripheral blood of infected patients.

Dendritic cells (DC) are targets for HIV-1 infection and may harbor distinct populations of virus variants. To test this hypothesis full length env genes have been amplified and sequenced from DC and T cells purified from the blood of five symptomatic HIV-1-infected patients. For three of the patients, showing slow and slow/standard disease progression, distinct subsets of HIV variants infected DC and T cells, and the diversity of the DC-derived env genes was less than that observed in T cells. Amino acid substitutions differentiating DC and T cell variants were dispersed throughout the length of the glycoproteins and were patient/HIV-1 strain specific. However, the V1 and V2 domains of T cell-derived clones were generally shorter than those from DC. These findings suggest that there may be distinct populations of HIV-1 variants infecting blood DC and T cells in patients showing slow and slow/standard disease progression.

Construction and biological characterization of an infectious molecular clone of HIV type 1GB8.

Here we report the construction, sequencing, and repair of a molecular clone of HIV-1GB8, a virus representative of HIV-1 subtype B strains circulating in the UK. The phenotype of virus produced by the clone matches that of the parental virus. The molecular clone will be used in the production of attenuated virus stocks for chemical inactivation to allow development of faccines based on killed whole virus preparations.

Construction and characterization of a full-length HIV-1(92UG001) subtype D infectious molecular clone.

Here we report the construction, sequencing, and biological characterization of a molecular clone of HIV-1(92UG001), a virus representative of subtype D strains circulating in Uganda. The virus produced by the clone has an aggressive syncytium-inducing phenotype, which matches that of the parental virus. This phenotype may be related to duplication of a binding site for a transcription factor, T cell factor 1alpha (TCF-1alpha), in the long terminal repeat of the virus.

Association between a defective CCR-5 gene and progression to disease in HIV infection.

We measured the effect(s) of CCR-5 genotype on disease progression by studying the frequency of a defective CCR-5 delta32 allele within a cohort of long-term infected individuals. An elevated frequency of CCR-5 delta32 heterozygotes within the cohort compared with a control population of blood donors was observed. An association between progression rate and CCR-5 delta32 heterozygosity was observed. Furthermore, analysis of proviral DNA V3 sequences from a subset of the cohort predicted that the majority of individuals (39 of 44) were infected with viruses predicted to utilize the beta-chemokine receptor CCR-5. The marked association between CCR-5 genotype and disease progression observed in this study may be a consequence of the predicted low frequency of CXCR-4-utilizing viruses present within the selected cohort.

CD8+ T-cell-mediated non-cytolytic suppression of human immuno-deficiency viruses.

Major histocompatibility (MHC)-restricted cytotoxic T-lymphocytes (CTL) kill human immunodeficiency virus (HIV)-infected cells. In addition, activated CD8(+) T-lymphocytes from HIV-infected individuals suppress virus replication in vitro by producing antiviral factor (CAF). The effector mechanism(s) of CAF involves modulation of HIV gene transcription, is non-cytolytic and mediated in part by soluble antiviral factors. Initially, CAF activity was shown to be more vigorous in activated CD8(+) cells and cell free supernatants (SNs) from asymptomatic individuals compared to those with AIDS, suggesting a protective role in vivo. CAF-mediated suppression is also evident in animal models of immunodeficiency virus infection. Several soluble molecules that contribute to non-cytolytic virus suppression have been characterised, including alpha- and beta-chemokines and interleukin-16 (IL-16), but these are distinct from CAF. Two agents possessing certain CAF-like characteristics, modified antithrombin 111 (AT111) and the human alpha-defensins, have been described but their antiviral mechanisms are not fully understood. CAF-secretion may not be virus-specific as similar activity is found in activated CD8(+) cells/SNs from humans and chimpanzees seronegative for HIV-1. Recent data indicates that the secretion of CAF is MHC-restricted and both cytolytic and non-cytolytic mechanisms are mediated by CTL. If the latter is correct, a single appropriate stimulus could be used to enhance both effector mechanisms in vivo. This paper reviews research aimed at characterising HIV-suppressive factors and raises other questions that must be considered for the development of prophylactic and therapeutic strategies leading to the safe and effective control of HIV.

Lack of detection of influenza genes in archived formalin-fixed, paraffin wax-embedded brain samples of encephalitis lethargica patients from 1916 to 1920.

A method was developed for detection of influenza genes in formalin-fixed brains of mice that had been experimentally infected with influenza A/NWS/33 (H1N1) virus. Using this technique, messenger ribonucleic acid (mRNA) of the beta-actin gene was detected in eight clinical brain samples from the 1916-1920 outbreak of encephalitis lethargica, showing preservation of particular mRNAs. However, we did not detect influenza nucleotide sequences of M, NP, and NS genes from these same samples. We conclude either that influenza was not the causative agent of encephalitis lethargica or, possibly, that the virus had a hit-and-run mechanism and was no longer present in the brain at the time of death of the patients.