CD8β Depletion Does Not Prevent Control of Viral Replication or Protection from Challenge in Macaques Chronically Infected with a Live Attenuated Simian Immunodeficiency Virus

We evaluated the contribution of CD8αβ+ T cells to control of live-attenuated simian immunodeficiency virus (LASIV) replication during chronic infection and subsequent protection from pathogenic SIV challenge. Unlike previous reports with a CD8α-specific depleting monoclonal antibody (mAb), the CD8β-specific mAb CD8β255R1 selectively depleted CD8αβ+ T cells without also depleting non-CD8+ T cell populations that express CD8α, such as natural killer (NK) cells and γδ T cells. Following infusion with CD8β255R1, plasma viremia transiently increased coincident with declining peripheral CD8αβ+ T cells. Interestingly, plasma viremia returned to predepletion levels even when peripheral CD8αβ+ T cells did not. Although depletion of CD8αβ+ T cells in the lymph node (LN) was incomplete, frequencies of these cells were 3-fold lower (P = 0.006) in animals that received CD8β255R1 than in those that received control IgG. It is possible that these residual SIV-specific CD8αβ+ T cells may have contributed to suppression of viremia during chronic infection. We also determined whether infusion of CD8β255R1 in the LASIV-vaccinated animals increased their susceptibility to infection following intravenous challenge with pathogenic SIVmac239. We found that 7/8 animals infused with CD8β255R1, and 3/4 animals infused with the control IgG, were resistant to SIVmac239 infection. These results suggest that infusion with CD8β255R1 did not eliminate the protection afforded to LASIV vaccination. This provides a comprehensive description of the impact of CD8β255R1 infusion on the immunological composition in cynomolgus macaques, compared to an isotype-matched control IgG, while showing that the control of LASIV viremia and protection from challenge can occur even after CD8β255R1 administration.IMPORTANCE Studies of SIV-infected macaques that deplete CD8+ T cells in vivo with monoclonal antibodies have provided compelling evidence for their direct antiviral role. These studies utilized CD8α-specific mAbs that target both the major (CD8αβ+) and minor (CD8αα+) populations of CD8+ T cells but additionally deplete non-CD8+ T cell populations that express CD8α, such as NK cells and γδ T cells. In the current study, we administered the CD8β-specific depleting mAb CD8β255R1 to cynomolgus macaques chronically infected with a LASIV to selectively deplete CD8αβ+ T cells without removing CD8αα+ lymphocytes. We evaluated the impact on control of virus replication and protection from pathogenic SIVmac239 challenge. These results underscore the utility of CD8β255R1 for studying the direct contribution of CD8αβ+ T cells in various disease states.

Associations between community-based physiotherapy for musculoskeletal injury and health related quality of life (EQ-5D): a multi-centre retrospective analysis

Background

Community-based musculoskeletal physiotherapy is used to improve function and health related quality of life (HRQoL). The purpose of this retrospective, multi-centre observational study was to determine the association between community-based physiotherapy management for musculoskeletal disorders and changes in HRQoL.

Methods

Four thousand one hundred twelve patients’ data were included in the study. Patients were included if they received a single period of treatment for a musculoskeletal injury or disorder. Patients were only included if they were being treated for a single morbidity. Patients received standard physiotherapy appropriate to their specific disorder, which could include health education/advice, exercise therapy, manual therapy, taping, soft tissue techniques, electrotherapy and/or acupuncture. Health related quality of life was assessed using the EQ-5D index.

Results

EQ-5D improved by 0.203 across all patients (d = 1.10). When grouped by anatomical site of symptom, the largest increases in EQ-5D was in foot pain (0.233; d = 1.29) and lumbar pain (0.231; d = 1.13). Improvements in EQ-5D greater than the minimum clinically important difference (MCID) were seen in 68.4% of all patients. The highest proportion of patients with positive responses to treatment were in ankle pain (74.2%) and thoracic pain (73.4%). The hand (40.5%), elbow (34.7%), and hip (33.9%) showed the greatest proportion of patients that did not respond to treatment.

Conclusions

Community-based musculoskeletal physiotherapy is associated with improved health related quality of life. A randomised controlled trial is needed to determine any causal relationship between community-based physiotherapy and health related quality of life improvements.

Instrumenting gait with an accelerometer: a system and algorithm examination

Gait is an important clinical assessment tool since changes in gait may reflect changes in general health. Measurement of gait is a complex process which has been restricted to the laboratory until relatively recently. The application of an inexpensive body worn sensor with appropriate gait algorithms (BWM) is an attractive alternative and offers the potential to assess gait in any setting. In this study we investigated the use of a low-cost BWM, compared to laboratory reference using a robust testing protocol in both younger and older adults. We observed that the BWM is a valid tool for estimating total step count and mean spatio-temporal gait characteristics however agreement for variability and asymmetry results was poor. We conducted a detailed investigation to explain the poor agreement between systems and determined it was due to inherent differences between the systems rather than inability of the sensor to measure the gait characteristics. The results highlight caution in the choice of reference system for validation studies. The BWM used in this study has the potential to gather longitudinal (real-world) spatio-temporal gait data that could be readily used in large lifestyle-based intervention studies, but further refinement of the algorithm(s) is required.

Integrating the roles of long and small non-coding RNA in brain function and disease

Regulatory RNA is emerging as the major architect of cognitive evolution and innovation in the mammalian brain. While the protein machinery has remained largely constant throughout animal evolution, the non protein-coding transcriptome has expanded considerably to provide essential and widespread cellular regulation, partly through directing generic protein function. Both long (long non-coding RNA) and small non-coding RNAs (for example, microRNA) have been demonstrated to be essential for brain development and higher cognitive abilities, and to be involved in psychiatric disease. Long non-coding RNAs, highly expressed in the brain and expanded in mammalian genomes, provide tissue- and activity-specific epigenetic and transcriptional regulation, partly through functional control of evolutionary conserved effector small RNA activity. However, increased cognitive sophistication has likely introduced concomitant psychiatric vulnerabilities, predisposing to conditions such as autism and schizophrenia, and cooperation between regulatory and effector RNAs may underlie neural complexity and concomitant fragility in the human brain.

The effect of caffeine mouth rinse on self-paced cycling performance

The aim of the study was to determine whether caffeine mouth rinse would improve 30 min self-paced cycling trial. Twelve healthy active males (age 20.5±0.7 years, mass 87.4±18.3 kg) volunteered for the study. They attended the laboratory on 3 separate occasions performing a 30 min self-paced cycling trial. On one occasion water was given as a mouth rinse for 5 s (PLA), on another occasion a 6.4% maltodextrin (CHO) solution was given for 5 s and finally a caffeine solution (containing 32 mg of caffeine dissolved in 125 ml water; CAF) was given for 5 s. Distance cycled, heart rate, ratings of perceived exertion, cadence, speed and power output were recorded throughout all trials. Distance cycled during the CAF mouth rinse trial (16.2±2.8 km) was significantly greater compared to PLA trial (14.9±2.6 km). There was no difference between CHO and CAF trials (P=0.89). Cadence, power and velocity were significantly greater during the CAF trial compared to both PLA and CHO (P<0.05). There were no differences between trials for heart rate and perceived exertion (P>0.05). Caffeine mouth rinse improves 30 min cycling performance by allowing the participant to increase cadence, power and velocity without a concurrent increase in perceived exertion and heart rate.

HAART and risk of tuberculosis in HIV-infected South African children: a multi-site retrospective cohort

SETTING

Four human immunodeficiency virus (HIV) clinics located at South African tertiary hospitals.

OBJECTIVE

To assess the effectiveness of highly active antiretroviral therapy (HAART) in reducing incident tuberculosis (TB) in HIV-infected children.

DESIGN

Retrospective cohort.

RESULTS

A total of 1132 children's records were included in the study. At entry to the cohort, the median (interquartile range [IQR]) age, CD4%, CD4 count and viral load of all children was respectively 6.3 years (4.1-8.8), 15% (9.0-22.2), 576 cells/mm(3) (287-960) and 160 000 copies/ml (54 941.5-449 683); 75.9% were started on HAART. The male:female ratio was 1:1, and median follow-up time was 1.7 years. In children whose follow-up included both pre-HAART and on-HAART periods, the incidence of clinically diagnosed TB was respectively 21.1 per 100 person-years (py; 95%CI 18.2-24.4) and 6.4/100 py (95%CI 4.8-8.1), and when restricted to confirmed cases, respectively 3.1/100 py (95%CI 2.2-4.2) and 0.8/100 py (95%CI 0.5-1.4). Only 23% of all cases of TB were microbiologically confirmed. Multivariate analyses showed that HAART reduced incident TB by approximately 70%, both for confirmed and all TB cases.

CONCLUSIONS

In this high TB burden country, the incidence of diagnosis of TB in HIV-infected children is at least as high as that of adults. HAART reduces incident TB, but further prospective TB preventive and diagnostic studies are urgently needed in children.

Management options, technologies and strategies for minimised mycotoxin contamination of rice

Ninety percent of the world's rice is produced and consumed in Asia. Millions of rice producers are resource-poor farmers with a rice area of less than one hectare. Yield increase and the introduction of double-cropping systems have ensured that rice production has kept up with an increasing demand. However, the increased quantities of grain and the second harvest, which is often in the wet season, have increased the problems in traditional postharvest systems. This can be particularly severe in the humid tropics, where post-harvest losses occur because of outdated management practices and technologies, and delays in post-harvest operations. Fungal infestation of rice grains can lead to discoloration, which results in price reductions in most markets. This can also result in rice being contaminated with mycotoxins, which is less visible to consumers. Contamination with ochratoxins, aflatoxins, and other mycotoxins have occasionally been reported in the literature. In the past, this was not seen as a significant problem and the focus was on other commodities such as maize and peanuts. However, recent studies and a massive recall of food products in Japan in September 2008, including sake, shoshu, and rice crackers made from imported rice from China and Vietnam, which were tested positive for aflatoxins, and also for pesticide residues, have renewed interest in looking at mycotoxin problems in rice. Exploratory studies in the Philippines compared best practice post-harvest management with the traditional management practices often used by smallholder farmers and small processors. It was concluded that synthesis of aflatoxin B1 is very likely in suboptimal post-harvest systems, with levels far above legislative limits. This indicates that there might be a considerable mycotoxin problem in rice from smallholder post-harvest operations. Improved post-harvest management options and technologies are available for diversified small-scale post-harvest systems. Small-scale combine harvesters, affordable and simple mechanical dryers and hermetic storage systems can help to avoid delays in the post-harvest chain and thus reduce mycotoxin contamination of rice. The development of strategies to scale out these improved practices and technologies to a large number of smallholder farmers will continue to be the main challenge.

Semliki Forest virus strongly reduces mosquito host defence signaling

The Alphavirus genus within the Togaviridae family contains several important mosquito-borne arboviruses. Other than the antiviral activity of RNAi, relatively little is known about alphavirus interactions with insect cell defences. Here we show that Semliki Forest virus (SFV) infection of Aedes albopictus-derived U4.4 mosquito cells reduces cellular gene expression. Activation prior to SFV infection of pathways involving STAT/IMD, but not Toll signaling reduced subsequent virus gene expression and RNA levels. These pathways are therefore not only able to mediate protective responses against bacteria but also arboviruses. However, SFV infection of mosquito cells did not result in activation of any of these pathways and suppressed their subsequent activation by other stimuli.

Characterization of gamma-aminobutyric acid receptor GABAB(1e), a GABAB(1) splice variant encoding a truncated receptor

We have identified a splice variant encoding only the extracellular ligand-binding domain of the gamma-aminobutyric acid B (GABA(B)) receptor subunit GABA(B(1a)). This isoform, which we have named GABA(B(1e)), is detected in both rats and humans. While GABA(B(1e)) is a minor component of the total pool of GABA(B(1)) transcripts detected in the central nervous system, it is the primary isoform found in all peripheral tissues examined. When expressed in a heterologous system, the truncated receptor is both secreted and membrane associated. However, GABA(B(1e)) lacks the ability to bind the radiolabeled antagonist [(3)H]CGP 54626A, activate G-protein coupled inwardly rectifying potassium channels, or inhibit forskolin-induced cAMP production when it is expressed alone or together with GABA(B(2)). Interestingly, when co-expressed with GABA(B(2)), not only does the truncated receptor heterodimerize with GABA(B(2)), the association is of sufficient avidity to disrupt the normal GABA(B(1a))/GABA(B(2)) association. Despite this strong interaction, GABA(B(1e)) fails to disrupt G-protein coupled inwardly rectifying potassium activation by the full-length heterodimer pair of GABA(B(1a))/GABA(B(2)).

Nephroblastoma overexpressed gene (NOV) codes for a growth factor that induces protein tyrosine phosphorylation

NOV (nephroblastoma overexpressed gene) is a member of the CCN (connective tissue growth factor [CTGF], Cyr61/Cef10, NOV) family of proteins. These proteins are cysteine-rich and are noted for having growth-regulatory functions. We have isolated the rat NOV gene, and the DNA sequence shares 90% identity with the mouse and 80% identity with the human sequences. The rat NOV gene was expressed in all rat tissues examined, including brain, lung, heart, kidney, liver, spleen, thymus and skeletal muscle. Higher levels of rat NOV mRNA were seen in the brain, lung and skeletal muscle compared to the other tissues. Examination of NOV expression in various human cell lines revealed that NOV was expressed in U87, 293, T98G, SK-N-MC and Hs683 but not in HepG2, HL60, THP1 and Jurkat. The human NOV gene was transfected into 293 cells and the expressed protein purified. When 3T3 fibroblasts were treated with this recombinant NOV protein, a dose-dependent increase in proliferation was observed. Analysis of tyrosine-phosphorylated proteins revealed that when 3T3 cells were treated with NOV, a 221 kDa protein was phosphorylated. These data suggest that NOV can act as a growth factor for some cells and binds to a specific receptor that leads to the phosphorylation of a 221 kDa protein.

Expression and characterization of a putative high affinity human soluble leptin receptor

Leptin, a circulating 16-kDa protein secreted by adipocytes, decreases body weight by reducing food intake and enhancing energy utilization. Leptin receptors that share homology to the glycoprotein gp130 have been recently cloned. In addition, differentially spliced leptin receptor messenger RNAs have been identified. Functional mutations in either the leptin or leptin receptor gene cause obesity. In the present study, expression of the full length human leptin receptor complementary DNA encoding the long cytoplasmic domain of leptin receptor in COS7 cells resulted in high affinity membrane binding of 125I-leptin (Ki approximately 200 pM); no detectable binding was present in the medium. In addition, we expressed the extracellular domain of human leptin receptor in COS7 cells and identified a soluble leptin receptor in the conditioned medium that binds human and mouse leptin with high affinity comparable with the full length membrane receptor. Transfected COS7 cells expressing the soluble leptin receptor also demonstrated modest specific 125I-leptin binding in whole cells, presumably due to association of the soluble leptin receptor to cell membrane proteins. Data from cross-linking studies identified two specific bands in the 125I-leptin/soluble leptin receptor complex with molecular masses of approximately 130-150 kDa and 300 kDa. The 130-150 kDa molecular mass was confirmed in Western blot analysis and Coomassie staining of the purified soluble receptor and probably represents the glycosylated form of the receptor. The 300-kDa band most likely represents a homodimer of the soluble leptin receptor complex because HPLC gel filtration analysis of the 125I-leptin/soluble leptin receptor complex identified a single peak corresponding to a molecular mass of approximately 340 kDa. The soluble leptin receptor antagonized 125I-leptin binding to the membrane receptor, suggesting its potential utility as a functional tool for determining the role of endogenous leptin.

A single mutation that increases maize seed weight

The maize endosperm-specific gene shrunken2 (Sh2) encodes the large subunit of the heterotetrameric starch synthetic enzyme adenosine diphosphoglucose pyrophosphorylase (AGP; EC 2.7.7.27). Here we exploit an in vivo, site-specific mutagenesis system to create short insertion mutations in a region of the gene known to be involved in the allosteric regulation of AGP. The site-specific mutagen is the transposable element dissociation (Ds). Approximately one-third (8 of 23) of the germinal revertants sequenced restored the wild-type sequence, whereas the remaining revertants contained insertions of 3 or 6 bp. All revertants retained the original reading frame 3' to the insertion site and involved the addition of tyrosine and/or serine. Each insertion revertant reduced total AGP activity and the amount of the SH2 protein. The revertant containing additional tyrosine and serine residues increased seed weight 11-18% without increasing or decreasing the percentage of starch. Other insertion revertants lacking an additional serine reduced seed weight. Reduced sensitivity to phosphate, a long-known inhibitor of AGP, was found in the high seed-weight revertant. This alteration is likely universally important since insertion of tyrosine and serine in the potato large subunit of AGP at the comparable position and expression in Escherichia coli also led to a phosphate-insensitive enzyme. These results show that single gene mutations giving rise to increased seed weight, and therefore perhaps yield, are clearly possible in a plant with a long history of intensive and successful breeding efforts.

Cloning and characterization of the human corticotropin-releasing factor-2 receptor complementary deoxyribonucleic acid

Two CRF receptor subtypes (CRF1 and CRF2 receptors) with distinct brain localizations and pharmacological profiles have recently been cloned and characterized. For the CRF2 receptor subtype, at least 2 splice forms with different 5'-coding sequences (CRF2 alpha and CRF2 beta) have been identified in rat. In this article, we report the genomic structure and the corresponding complementary DNA (cDNA) sequence of the human CRF2 receptor. The gene coding for human CRF2 receptor consists of at least 12 exons and spans approximately 30 kilobases. The cDNA sequence in the protein-coding region is 94% identical to that of the reported rat CRF2 alpha receptor. At present, there is no evidence for the existence of a CRF2 beta receptor homolog in humans. The encoded receptor is 411 amino acids in length and is 70% identical to the human CRF1 receptor, with least sequence homology in the N-terminal extracellular domain (47% identical). Cells transfected with the full-length human CRF2 receptor cDNA responded to rat/human CRF and sauvagine by increasing the intracellular cAMP level, with EC50 values of approximately 20 and 1 nM, respectively. The CRF- and sauvagine-induced accumulation of intracellular cAMP could be competitively inhibited by the CRF receptor antagonist D-Phe-CRF. This pharmacological profile was comparable to that of the rat CRF2 alpha receptor. The relative abundance of the CRF2 receptor messenger RNA appears to be lower in humans than in rats for the tissues studied thus far.

Pulmonary infiltrates after heart-lung transplantation: evaluation by serial transbronchial biopsies

Since January 1988, prospective serial transbronchial lung biopsies have been performed as a diagnostic procedure to facilitate the care of recipients of heart-lung transplants. Eighty-five cardiac and 70 transbronchial lung biopsies have been prospectively performed in 10 patients beginning within the first week of transplantation. Forty-eight percent (34/70) of the transbronchial lung biopsies and 16.5% (14/85) of the heart biopsies were positive for either rejection or infection. Pulmonary rejection was evident by a perivascular lymphocytic infiltrate that cleared with pulse steroid therapy. Pulmonary and cardiac rejection were present synchronously on six occasions and asynchronously on 16 occasions (nine pulmonary and seven cardiac). Four patients had early cytomegalovirus pneumonitis on biopsy specimen and were successfully treated with ganciclovir. Of the 40 clinically indicated biopsies, 29 (72.5%) were positive for rejection or infection and guided subsequent therapy. In summary, transbronchial lung biopsies have provided prompt (within 24 hours) serial diagnostic information that has guided successful treatment of infection (cytomegalovirus, aspergillosis, and Pneumocystis) and rejection. Asynchronous rejection of the heart and lungs has been conclusively demonstrated. With the early detection of rejection and infection, we are optimistic that chronic airway disease in patients with a heart-lung transplant may be reduced.

The herbicide glyphosate

Glyphosate has broad spectrum herbicidal activity against a wide range of annual and perennial weeds. The environmental properties of this herbicide such as its soil immobility, rapid soil inactivation and soil biodegradation are outstanding. This herbicide is practically non-toxic to non-plant life forms such as aquatic and avian species, animals and man. Metabolism studies with pure bacterial cultures indicate that glyphosate is metabolized to either aminomethylphosphonate and glyoxylate or sarcosine and phosphate in most bacteria. The enzyme C-P lyase, which catalyzes the cleavage of the carbon-phosphorus bond of phosphonates including glyphosate, appears to be complex, containing multiple subunits. Mode of action studies have demonstrated that glyphosate kills plants by inhibiting the enzyme 5-enolpyruvylshikimate-3-phosphate synthase, involved in the biosynthesis of aromatic compounds. The status of our understanding of these aspects of glyphosate is reviewed.

A Reflex Plotter investigation into the dimensional stability of alginate impressions following disinfection by varying regimes employing 2.2 per cent glutaraldehyde

Alginate impressions of an acrylic study cast pair were disinfected to a variety of regimes using 2.2 per cent glutaraldehyde. A number of linear measurements on the resultant plaster study casts were made using a Reflex Plotter to assess the effect on the dimensional stability of the casts. Significant differences were found for a number of the variables measured. Quantitatively these differences were small and of limited clinical significance; they may, however, be of greater significance where serial records are being collected for research.

Nucleotide sequence at the end of the gene for the RNA polymerase beta' subunit (rpoC)

We have determined the DNA sequence surrounding the transcription terminator following rpoC, the gene that codes for the beta' subunit of RNA polymerase in E. coli K12. The 2044 bp sequence obtained contains the distal 335 codons of rpoC followed by a 212 bp non-coding region and a second open reading frame (ORFa) of 179 codons. The final 181 nucleotides of the sequence form the 5' end of a third open reading frame (ORFb). The in vivo 3' end of the rpoC mRNA was located by analysis of RNA/DNA hybrids cleaved with nuclease S1 (S1 mapping). These results indicated that the major transcription termination of the rplJL-rpoBC transcription unit occurs a short distance past the translation stop codon for rpoC. Four regions of symmetry, suggesting secondary structure in the mRNA, were found in the DNA sequence near the rpoC translation termination codon. The last of these hairpin structures is similar to other rho-independent transcription terminators and its 3' end coincides with the end of the rpoC mRNA as predicted by S1-mapping. Inspection of the open reading frames indicates that rpoC uses a high percentage of codons that are recognized by the major tRNA species of E. coli while ORFa and ORFb contain many codons recognized by minor tRNA species. ORFa specifies a very basic peptide.

Attenuation and processing of RNA from the rplJL--rpoBC transcription unit of Escherichia coli

Attenuation and processing of the mRNA from the ribosomal protein-RNA polymerase operon rplJL--rpoBC have been demonstrated by the analysis of nuclease SI-resistant RNA . DNA hybrids. These hybrids were formed between RNA produced in vivo and specific DNA restriction fragments which span the rplL--rpoB intercistronic region. The 3' end of the predominant attenuated RNA lies 69 nucleotides beyond the end of the rplL gene following sequence features that are similar to those of other known attenuators. The nonattenuated transcript is normally cleaved in the intercistronic region. However, in an RNase III mutant strain, the hybrids corresponding to the cleaved nonattenuated mRNAs disappear and the expected full-sized hybrid is seen. We have localized the cleavage to an area of possible secondary structure in the transcript approximately 200 nucleotides beyond the end of the rplL gene. This demontrates RNase III processing of Escherichia coli mRNA. The methods used in this study permit the examination of specific ends of large and complex polycistronic mRNAs. Such experiments should help in understanding how posttranscriptional events influence gene expression.

Control features within the rplJL-rpoBC transcription unit of Escherichia coli

Gene fusions constructed in vitro have been used to examine transcription regulatory signals from the operon which encodes ribosomal proteins L10 and L7/12 and the RNA polymerase beta and beta' subunits (the rplJL-rpoBC operon). Portions of this operon, which were obtained by in vitro deletions, have been placed between the ara promoter and the lacZ gene in the gene-fusion plasmid pMC81 developed by M. Casadaban and S. Cohen. The effect of the inserted DNA segment on the expression of the lacZ gene (in the presence and absence of arabinose) permits the localization of regulatory signals to discrete regions of the rplJL-rpoBC operon. An element that reduces the level of distal gene expression to one-sixth is located on a fragment which spans the rplL-rpoB intercistronic region. This strongly supports the idea that there is an attenuator in this region. The terminator for the operon is located on a fragment which spans the 3' end of the rpoC gene. The major promoter for the operon precedes the rplJ gene [Yamamoto, M. & Nomura, M. (1978) Proc. Natl. Acad. Sci. USA 75, 3891-3895 and Linn, T. & Scaife, J. (1978) Nature (London) 276, 33-37] and was not examined in this study. However, a weak promoter is observed on the fragment that spans the rplJ-rplL intercistronic region. Other regions of the operon may also contain weak promoters. The contribution of these elements to the regulation of this complex operon is discussed.

Spina Bifida Occulta with Trophic Changes in the Legs

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