A global phosphosite-correlated network map of Thousand And One Kinase 1 (TAOK1)

Thousand and one amino acid kinase 1 (TAOK1) is a sterile 20 family Serine/Threonine kinase linked to microtubule dynamics, checkpoint signaling, DNA damage response, and neurological functions. Molecular-level alterations of TAOK1 have been associated with neurodevelopment disorders and cancers. Despite their known involvement in physiological and pathophysiological processes, and as a core member of the hippo signaling pathway, the phosphoregulatory network of TAOK1 has not been visualized. Aimed to explore this network, we first analyzed the predominantly detected and differentially regulated TAOK1 phosphosites in global phosphoproteome datasets across diverse experimental conditions. Based on 709 qualitative and 210 quantitative differential cellular phosphoproteome datasets that were systematically assembled, we identified that phosphorylation at Ser421, Ser9, Ser965, and Ser445 predominantly represented TAOK1 in almost 75% of these datasets. Surprisingly, the functional role of all these phosphosites in TAOK1 remains unexplored. Hence, we employed a robust strategy to extract the phosphosites in proteins that significantly correlated in expression with predominant TAOK1 phosphosites. This led to the first categorization of the phosphosites including those in the currently known and predicted interactors, kinases, and substrates, that positively/negatively correlated with the expression status of each predominant TAOK1 phosphosites. Subsequently, we also analyzed the phosphosites in core proteins of the hippo signaling pathway. Based on the TAOK1 phosphoregulatory network analysis, we inferred the potential role of the predominant TAOK1 phosphosites. Especially, we propose pSer9 as an autophosphorylation and TAOK1 kinase activity-associated phosphosite and pS421, the most frequently detected phosphosite in TAOK1, as a significant regulatory phosphosite involved in the maintenance of genome integrity. Considering that the impact of all phosphosites that predominantly represent each kinase is essential for the efficient interpretation of global phosphoproteome datasets, we believe that the approach undertaken in this study is suitable to be extended to other kinases for accelerated research.

A novel loop-mediated isothermal amplification (LAMP) assay to diagnose feline panleukopenia

Protoparvovirus carnivoran1, known commonly as feline panleukopenia virus (FPV) is a highly contagious and environmentally stable parvovirus of domestic as well as wild felids. A rapid and robust diagnostic tool will aid in implementing prompt treatment and control measures. A loop-mediated isothermal amplification (LAMP) as a point-of-care diagnostic tool for diagnosing feline panleukopenia was standardised using faecal samples of cats. The assay will reduce the cost and time required to diagnose feline panleukopenia. A set of two outer primers (F3 and B3) and two inner primers (FIP and BIP) were designed to target the viral polypeptide (VP2) gene of FPV. Optimisation of the LAMP reaction was done at 60 °C for one hour after an initial denaturation at 95 °C for five minutes. Visualisation of the result based on the addition of SYBR Green 1 dye offered an easy and reliable diagnosis. The detection limit of the standardised LAMP assay was as low as 1.25 ng/μl of the target DNA. Species specificity of the LAMP primers revealed no amplification of the non-target DNA of any other species except that of the canine parvovirus DNA template. DNA extracted from 100 PCR-positive and 20 PCR-negative faecal samples were subjected to the standardised assay and compared with PCR. Analysis of the results revealed that the LAMP assay was 100% sensitive and 90% specific compared to PCR. The LAMP assay could be a reliable tool for the point-of-care diagnosis of feline panleukopenia in limited resource settings.

Potential protein kinase inhibitors that target G-quadruplex DNA structures in the human telomeric regions

Telomeric regions contain Guanine-rich sequences arranged in a planar manner and connected by Hoogsteen hydrogen bonds that can fold into G-quadruplex (G4) DNA structures, and can be stabilized by monovalent metal cations. The presence of G4 DNA holds significance in cancer-related processes, especially due to their regulatory potential at transcriptional and translational levels of oncogene and tumor suppressor genes. The objective of this current research is to explore the evolving realm of FDA-approved protein kinase inhibitors, with a specific emphasis on their capacity to stabilize the G4 DNA structures formed at the human telomeric regions. This involves investigating the possibility of repurposing FDA-approved protein kinase inhibitors as a novel approach for targeting multiple cancer types. In this context, we have selected 16 telomeric G4 DNA structures as targets and 71 FDA-approved small-molecule protein kinase inhibitors as ligands. To investigate their binding affinities, molecular docking of human telomeric G4 DNA with nuclear protein kinase inhibitors and their corresponding co-crystalized ligands were performed. We found that Ponatinib and Lapatinib interact with all the selected G4 targets, the binding free energy calculations, and molecular dynamic simulations confirm their binding efficacy and stability. Thus, it is hypothesized that Ponatinib and Lapatinib may stabilize human telomeric G4 DNA in addition to their ability to inhibit BCR-ABL and the other members of the EGFR family. As a result, we also hypothesize that the stabilization of G4 DNA might represent an additional underlying mechanism contributing to their efficacy in exerting anti-cancer effects.

Tyr352 as a Predominant Phosphosite in the Understudied Kinase and Molecular Target, HIPK1: Implications for Cancer Therapy

Homeodomain-interacting protein kinase 1 (HIPK1) is majorly found in the nucleoplasm. HIPK1 is associated with cell proliferation, tumor necrosis factor-mediated cellular apoptosis, transcription regulation, and DNA damage response, and thought to play significant roles in health and common diseases such as cancer. Despite this, HIPK1 remains an understudied molecular target. In the present study, based on a systematic screening and mapping approach, we assembled 424 qualitative and 44 quantitative phosphoproteome datasets with 15 phosphosites in HIPK1 reported across multiple studies. These HIPK1 phosphosites were not currently attributed to any functions. Among them, Tyr352 within the kinase domain was identified as the predominant phosphosite modulated in 22 differential datasets. To analyze the functional association of HIPK1 Tyr352, we first employed a stringent criterion to derive its positively and negatively correlated protein phosphosites. Subsequently, we categorized the correlated phosphosites in known interactors, known/predicted kinases, and substrates of HIPK1, for their prioritized validation. Bioinformatics analysis identified their significant association with biological processes such as the regulation of RNA splicing, DNA-templated transcription, and cellular metabolic processes. HIPK1 Tyr352 was also identified to be upregulated in Her2+ cell lines and a subset of pancreatic and cholangiocarcinoma tissues. These data and the systems biology approach undertaken in the present study serve as a platform to explore the functional role of other phosphosites in HIPK1, and by extension, inform cancer drug discovery and oncotherapy innovation. In all, this study highlights the comprehensive phosphosite map of HIPK1 kinase and the first of its kind phosphosite-centric analysis of HIPK1 kinase based on global-level phosphoproteomics datasets derived from human cellular differential experiments across distinct experimental conditions.

VirhostlncR: A comprehensive database to explore lncRNAs and their targets in viral infections

Long non-coding-RNAs (lncRNAs) are an expanding set of cis-/trans-regulatory RNA genes that outnumber the protein-coding genes. Although being increasingly discovered, the functional role of the majority of lncRNAs in diverse biological conditions is undefined. Increasing evidence supports the critical role of lncRNAs in the emergence, regulation, and progression of various viral infections including influenza, hepatitis, coronavirus, and human immunodeficiency virus. Hence, the identification of signature lncRNAs would facilitate focused analysis of their functional roles accounting for their targets and regulatory mechanisms associated with infections. Towards this, we compiled 2803 lncRNAs identified to be modulated by 33 viral strains in various mammalian cell types and are provided through the resource named VirhostlncR (http://ciods.in/VirhostlncR/). The information on each of the viral strains, their multiplicity of infection, duration of infection, host cell name and cell types, fold change of lncRNA expression, and their specific identification methods are integrated into VirhostlncR. Based on the current datasets, we report 150 lncRNAs including differentiation antagonizing non-protein coding RNA (DANCR), metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), maternally expressed gene 3 (MEG3), nuclear paraspeckle assembly transcript 1 (NEAT1), and plasmacytoma variant translocation 1 (PVT1) to be perturbed by two or more viruses. Analysis of viral protein interactions with human transcription factors (TFs) or TF-containing protein complexes identified that distinct viruses can transcriptionally regulate many of these lncRNAs through multiple protein complexes. Together, we believe that the current dataset will enable priority selection of lncRNAs for identification of their targets and serve as an effective platform for the analysis of noncoding RNA-mediated regulations in viral infections.

Diabetes mellitus is not a predictor of poor TB treatment outcomes

OBJECTIVE: To investigate whether diabetes mellitus (DM) influences TB treatment outcomes.METHODS: This was a retrospective observational cohort study of all notified TB cases from a large London TB centre over a 5-year period. WHO criteria were used to define TB treatment outcomes.RESULTS: The prevalence of DM at TB treatment initiation was 15% (126/838). Most patients (83.3%, 105/126) were on hypoglycaemic treatment and well-controlled (median glycated haemoglobin 53.5 mmol/mol). DM patients were older, more likely to be of Asian ethnicity and had a higher pre-treatment weight. Time from presentation to treatment initiation was longer (median 87.5 vs. 63 days; P < 0.001), while they were significantly more comorbid (median Charlson Comorbidity Index 3 vs. 0; P < 0.001). Overall, favourable treatment outcomes were recorded for 89.5% of patients (87.7% vs. 89.8% for DM and non-DM patients respectively, P = 0.52). In multivariable analysis, DM was not associated with unfavourable TB treatment outcomes (OR 0.49, 95% CI 0.23-1.04, P = 0.06). Independent predictors of unfavourable outcome included age, cavitation, chronic neurological disease and malignant neoplasm.CONCLUSIONS: In a well-resourced setting, with predominantly well-controlled DM patients on treatment, DM was not an independent predictor of unfavourable TB treatment outcomes.

Molecular detection of quaternary ammonium compound resistance genes of Staphylococcus aureus from udder surface and mastitis milk of bovines

Quaternary ammonium compounds (QAC) are widely used biocides in the field of medical and veterinary practice. Resistance to QACs is an emerging problem due to this widespread use. The present study was undertaken to detect the presence of genes that contribute to resistance to QACs in Staphylococcus aureus isolates obtained from udder surface and mastitis milk. A total 22 isolates of S. aureus were obtained from udder washings and milk of bovine mastitis cases. Among these, seventeen isolates were from udder wash samples and five isolates from clinical and subclinical cases of mastitis. Broth microdilution assay was performed to assess the minimum inhibitory concentration (MIC) of the isolates against Cetyltrimethylammonium bromide (CTAB), a QAC. Polymerase chain reaction (PCR) was done targeting qac A/B gene which codes for efflux pump which targets QACs. In the present study qac A/B gene was detected in seven out of 22 isolates of S. aureus. Three of these isolates were obtained from udder washings before milking and four, after milking. None of the S. aureus isolates from mastitis milk possessed the gene. The average minimum inhibitory concentration of qac A/B positive isolates against CTAB was 0.63 ± 0.55 μg/ml. The average MIC between qac A/B positive and negative isolates were statistically insignificant. The study points to the fact that multiple factors could be contributing to biocide resistance in S. aureus.

Impact of age on catheter ablation of premature ventricular contractions

Funding Acknowledgements

Type of funding sources: None.

Introduction

Catheter ablation (CA) of frequent premature ventricular contractions (PVC) is increasingly performed in older patients as the population ages.

Purpose

The purpose of this study was to assess the impact of age on procedural characteristics, safety and efficacy on PVC ablations.

Methods

Consecutive patients with symptomatic PVCs undergoing CA between 2015 and 2020 were evaluated. Acute ablation success was defined as the elimination of PVCs at the end of the procedure. Sustained success was defined as an elimination of symptoms, and  ≥80% reduction of PVC burden determined by Holter-ECG during long-term follow. Patients were sub-grouped based on age (&lt; 65 years vs. ≥ 65 years).

Results

A total of 114 patients were enrolled (median age 64 years, 71% males) and followed up for a median duration of 228 days. Baseline and procedural data were similar in both age groups. A left-sided origin of PVCs was more frequently observed in the elderly patient group compared to younger patients (83% vs. 67%, p = 0.04, Figure 1). The median procedure time was significantly shorter in elderly patients (160 min vs. 193 min, p = 0.02). The rates of both acute (86% vs. 92%, p = 0.32) and sustained success (70% vs. 71%, p = 0.90) were similar between groups. Complications rates (3.7%) did not differ between the two groups.

Conclusion

In a large series of patients with a variety of underlying arrhythmia substrates, similar rates of acute procedural success, complications, and ventricular arrhythmia-free-survival were observed after CA of PVCs. Older age alone should not be a reason to withhold CA of PVCs. Abstract Figure 1

Effect of general and local anesthesia on the vagal response characteristics during ganglionated plexus ablation

Funding Acknowledgements

Type of funding sources: None.

Background

The effect of different anesthetics on the function of the autonomic nervous system (ANS) is not well known. As a relatively new treatment option, ganglionated plexus (GP) ablation aims to modify the behavior of the cardiac ANS to prevent some/all of the autonomic processes occurring in vasovagal syncope (VVS) by using endocardial ablation techniques.

Purpose

The purpose of this study was to determine the effects midazolam and propofol on the vagal response (VR) characteristics during GP ablation in patients with vasovagal syncope (VVS).

Methods

Forty consecutive patients undergoing GP ablation for VVS were divided to receive local anesthesia with midazolam (group 1, n = 29) or general anesthesia with propofol (group EA, n = 11). All GP sites were detected by using previously defined fragmented electrogram based strategy. VR was defined on 3 levels: 1) R-R interval increased by 50% (level 1); 2) R-R interval increased by 20-50% (level 2); and 3) R-R interval increase lower than 20% (level 3).

Results

Baseline characteristics and mean follow-up times were comparable between groups. In both groups, the left superior GP (LSGP) was the most common GP site at which a VR was observed. However, there was a significant difference between groups for level of VR. While ablation on the LSGP caused a level 1 VR in 89.6% of cases in group 1, level 1 VR was seen in 22.2% of cases in group 2 (p &lt; 0.0001). Similarly, ratio of level 1 VR during ablation on the left inferior GP (LIGP) was significantly lower in group 2 (44.8% vs 9%, p = 0.034). Once cut-off for VR was decreased to level 2, the ratio of (+) VR increased to 90.9% during ablation on the LSGP in group 2. Level 2 VR was detected in 45.4% of cases during ablation on the LIGP. Ratio of positive VRs in any level was lower than 20% during ablation on the right superior and inferior GPs in both groups. During a mean follow-up time of 12.1 ± 7 months, all but 2 (5%) of 40 patients were free of syncope.

Conclusions

The autonomic nervous tone might be affected in different ways by local and general anesthesia. Propofol may reveal a shift in the sympathovagal balance toward sympathetic predominance which may cause a blunting on VR during GP ablation. Further randomized, controlled and multicenter studies should be performed to confirm these findings.

A QSAR and molecular modelling study towards new lead finding: polypharmacological approach to Mycobacterium tuberculosis

Developing effective inhibitors against Mycobacterium tuberculosis (Mtb) is a challenging task, primarily due to the emergence of resistant strains. In this study, we have proposed and implemented an in silico guided polypharmacological approach, which is expected to be effective against resistant strains by simultaneously inhibiting several potential Mtb drug targets. A combination of pharmacophore and QSAR based virtual screening strategy taking three key targets such as InhA (enoyl-acyl-carrier-protein reductase), GlmU (N-acetyl-glucosamine-1-phosphate uridyltransferase) and DapB (dihydrodipicolinate reductase) have resulted in initial 784 hits from Asinex database of 435,000 compounds. These hits were further subjected to docking with 33 Mtb druggable targets. About 110 potential polypharmacological hits were taken by integrating the aforementioned screening protocols. Further screening was conducted by taking various parameters and properties such as cell permeability, drug-likeness, drug-induced phospholipidosisand structural alerts. A consensus analysis has yielded 59 potential hits that pass through all the filters and can be prioritized for effective drug-resistant tuberculosis. This study proposes about nine potential hits which are expected to be promising molecules, having not only drug-like properties, but also being effective against multiple Mtb targets.

Family-led rehabilitation after stroke in India (ATTEND): a randomised controlled trial

BACKGROUND

Most people with stroke in India have no access to organised rehabilitation services. The effectiveness of training family members to provide stroke rehabilitation is uncertain. Our primary objective was to determine whether family-led stroke rehabilitation, initiated in hospital and continued at home, would be superior to usual care in a low-resource setting.

METHODS

The Family-led Rehabilitation after Stroke in India (ATTEND) trial was a prospectively randomised open trial with blinded endpoint done across 14 hospitals in India. Patients aged 18 years or older who had had a stroke within the past month, had residual disability and reasonable expectation of survival, and who had an informal family-nominated caregiver were randomly assigned to intervention or usual care by site coordinators using a secure web-based system with minimisation by site and stroke severity. The family members of participants in the intervention group received additional structured rehabilitation training-including information provision, joint goal setting, carer training, and task-specific training-that was started in hospital and continued at home for up to 2 months. The primary outcome was death or dependency at 6 months, defined by scores 3-6 on the modified Rankin scale (range, 0 [no symptoms] to 6 [death]) as assessed by masked observers. Analyses were by intention to treat. This trial is registered with Clinical Trials Registry-India (CTRI/2013/04/003557), Australian New Zealand Clinical Trials Registry (ACTRN12613000078752), and Universal Trial Number (U1111-1138-6707).

FINDINGS

Between Jan 13, 2014, and Feb 12, 2016, 1250 patients were randomly assigned to intervention (n=623) or control (n=627) groups. 33 patients were lost to follow-up (14 intervention, 19 control) and five patients withdrew (two intervention, three control). At 6 months, 285 (47%) of 607 patients in the intervention group and 287 (47%) of 605 controls were dead or dependent (odds ratio 0·98, 95% CI 0·78-1·23, p=0·87). 72 (12%) patients in the intervention group and 86 (14%) in the control group died (p=0·27), and we observed no difference in rehospitalisation (89 [14%]patients in the intervention group vs 82 [13%] in the control group; p=0·56). We also found no difference in total non-fatal events (112 events in 82 [13%] intervention patients vs 110 events in 79 [13%] control patients; p=0·80).

INTERPRETATION

Although task shifting is an attractive solution for health-care sustainability, our results do not support investment in new stroke rehabilitation services that shift tasks to family caregivers, unless new evidence emerges. A future avenue of research should be to investigate the effects of task shifting to health-care assistants or team-based community care.

FUNDING

The National Health and Medical Research Council of Australia.

Biofunctionalization of conductive hydrogel coatings to support olfactory ensheathing cells at implantable electrode interfaces

Mechanical discrepancies between conventional platinum (Pt) electrodes and neural tissue often result in scar tissue encapsulation of implanted neural recording and stimulating devices. Olfactory ensheathing cells (OECs) are a supportive glial cell in the olfactory nervous system which can transition through glial scar tissue while supporting the outgrowth of neural processes. It has been proposed that this function can be used to reconnect implanted electrodes with the target neural pathways. Conductive hydrogel (CH) electrode coatings have been proposed as a substrate for supporting OEC survival and proliferation at the device interface. To determine an ideal CH to support OECs, this study explored eight CH variants, with differing biochemical composition, in comparison to a conventional Pt electrodes. All CH variants were based on a biosynthetic hydrogel, consisting of poly(vinyl alcohol) and heparin, through which the conductive polymer (CP) poly(3,4-ethylenedioxythiophene) was electropolymerized. The biochemical composition was varied through incorporation of gelatin and sericin, which were expected to provide cell adherence functionality, supporting attachment, and cell spreading. Combinations of these biomolecules varied from 1 to 3 wt %. The physical, electrical, and biological impact of these molecules on electrode performance was assessed. Cyclic voltammetry and electrochemical impedance spectroscopy demonstrated that the addition of these biological molecules had little significant effect on the coating's ability to safely transfer charge. Cell attachment studies, however, determined that the incorporation of 1 wt % gelatin in the hydrogel was sufficient to significantly increase the attachment of OECs compared to the nonfunctionalized CH.

A method for the automated long-term monitoring of three-spined stickleback Gasterosteus aculeatus shoal dynamics

This paper describes and evaluates a flexible, non-invasive tagging system for the automated identification and long-term monitoring of individual three-spined sticklebacks Gasterosteus aculeatus. The system is based on barcoded tags, which can be reliably and robustly detected and decoded to provide information on an individual's identity and location. Because large numbers of fish can be individually tagged, it can be used to monitor individual- and group-level dynamics within fish shoals.

The effect of cyclosporin-A on peri-operative myocardial injury in adult patients undergoing coronary artery bypass graft surgery: a randomised controlled clinical trial

Objective

Cyclosporin-A (CsA) has been reported to reduce myocardial infarct size in both the experimental and clinical settings. This protective effect is dependent on its ability to prevent the opening of the mitochondrial permeability transition pore, a critical determinant of cell death in the setting of acute ischaemia-reperfusion injury. Whether CsA can reduce the extent of peri-operative myocardial injury (PMI) in patients undergoing coronary artery bypass graft (CABG) surgery is unknown, and is investigated in this randomised controlled clinical trial.

Methods

78 adult patients undergoing elective CABG surgery were randomised to receive either an intravenous bolus of CsA (2.5 mg/kg) or placebo administered after induction of anaesthesia and prior to sternotomy. PMI was assessed by measuring serum cardiac enzymes, troponin T (cTnT) and CK-MB at 0, 6, 12, 24, 48 and 72 h after surgery.

Results

There was no significant difference in mean peak cTnT levels between control (n=43) and CsA treatment (n=40) patients (0.56±0.06 ng/mL with control vs 0.35±0.05 ng/mL with CsA; p=0.07). However, in higher-risk patients with longer cardiopulmonary bypass times, there was a significant reduction in PMI with CsA therapy (p=0.049), with a reduced postoperative cTnT rise by 0.03 ng/mL for every 10 min, when compared with control.

Conclusions

In patients with longer cardiopulmonary bypass times, a single intravenous bolus of CsA administered prior to CABG surgery reduced the extent of PMI.

Chronic pain and its impact on quality of life following a traumatic rib fracture

PURPOSE

Traumatic rib fractures account for 7-40 % of trauma admissions and most of them heal spontaneously and do not contribute to disability. The prevalence of chronic pain and its impact on quality of life following a traumatic rib fracture has not been studied adequately.

METHODS

A retrospective review of electronic medical records of all the traumatic rib fracture admissions from January 2007 to December 2008 was conducted. This was followed up with a brief telephonic survey of the following questions: (1) Do you have pain following the trauma? (2) If YES, how severe is your pain from a score of zero to ten? (3) Does the pain affect your life style? (4) Does the pain affect your work? (5) Do you need to take regular pain medications?

RESULTS

One hundred and two patients responded to the survey and 23 patients (22.5 %) complained of chronic persistent pain. In patients with pain, six patients (26 %) had chronic pain that required regular use of analgesics, eight patients (35 %) complained of impairment of work life, and three patients (13 %) complained of impairment of personal quality of life. Chronic pain was not related to age, number of ribs fractured, flail chest, hemothorax and/or pneumothorax, chest tube insertion, or Injury Severity Score (ISS).

CONCLUSION

This study confirms the high incidence of chronic pain after a traumatic rib fracture. While the majority of the patients can manage this pain without interference of their quality of life, a few do suffer from life style/work interference and may have to resort to regular analgesic usage.

Imaging physicochemical reactions occurring at the pore surface in binary bioactive glass foams by micro ion beam analysis

In this work, the physicochemical reactions occurring at the surface of bioactive sol-gel derived 3D glass scaffolds via a complete PIXE characterization were studied. 3D glass foams in the SiO(2)-CaO system were prepared by sol-gel route. Samples of glass scaffolds were soaked in biological fluids for periods up to 2 days. The surface changes were characterized using particle induced X-ray emission (PIXE) associated to Rutherford backscattering spectroscopy (RBS), which are efficient methods to perform quantitative chemical maps. Elemental maps of major and trace elements at the glass/biological fluids interface were obtained at the micrometer scale for every interaction time. Results revealed interconnected macropores and physicochemical reactions occurring at the surface of pores. The micro-PIXE-RBS characterization of the pores/biological fluids interface shows the glass dissolution and the rapid formation of a Ca rich layer with the presence of phosphorus that came from biological fluids. After 2 days, a calcium phosphate-rich layer containing magnesium is formed at the surface of the glass scaffolds. We demonstrate that quantities of phosphorus provided only by the biological medium have a significant impact on the development and the formation of the phosphocalcic layer.

CD38 expression on CD8 T cells has a weak association with CD4 T-cell recovery and is a poor marker of viral replication in HIV-1-infected patients on antiretroviral therapy

OBJECTIVE

The aim of the study was to determine whether the expression of CD38 on CD8 T cells can identify patients with virological failure on antiretroviral therapy (ART).

DESIGN

This was a cross-sectional study of patients attending a single HIV clinic in London.

METHODS

The expression of CD38 on CD8 T cells was assessed using a biologically calibrated flow cytometry protocol. Patients were characterized by lymphocyte subset and viral load measurements. Characteristics including historical CD4 T cell counts, therapeutic history, co-infections and demographics were obtained from medical records.

RESULTS

Elevated levels of CD8 CD38(high) T cells were found in HIV-1-infected patients who failed to suppress viral replication with ART; however, this parameter lacked sufficient sensitivity and specificity to replace viral load testing in assessing the efficacy of ART. Increased levels of CD8 CD38(high) cells were associated with reduced CD4 T cell counts in HIV-1-infected patients on ART after correcting for known determinants of CD4 T-cell recovery.

CONCLUSIONS

The expression of CD38 on CD8 T cells lacks sufficient sensitivity and specificity to be used as a surrogate marker for viral load to monitor HIV-1 infection. T-cell activation is associated with reduced CD4 T-cell reconstitution in patients receiving ART.

Biochemical diagnosis of placental infarction/damage: acutely rising alkaline phosphatase

There are currently no simple tests in clinical use to detect acute placental damage. A case is described to demonstrate that a routinely used measurement such as alkaline phosphatase (ALP) can be employed to detect acute damage to the placenta. Seventeen serial blood samples, three pre-delivery, were collected from a 22-year-old primigravida who delivered a stillborn baby. Retrospectively, blood samples were analysed for total and heat-stable ALP as well as human chorionic gonadotropin (hCG) and alpha-fetoprotein (AFP) as a measure of placental function when an unusual pattern of change in ALP was noticed. Histological examination of the placenta revealed new and old placental infarcts. Total and heat-stable ALPs as well as AFP peaked by more than eight-, 19- and two-fold, respectively over 16 h. Plasma hCG fell sharply even before delivery of placenta by five-fold over 16 h before further falling slowly to baseline. The fall in hCG is also consistent with the placental damage being acute and critical. As far as we are aware this is the first description of changes in circulating proteins reflecting placental damage.

Non-nucleoside reverse transcriptase inhibitors: a review

Non-nucleoside reverse transcriptase inhibitors form the backbone of antiretroviral treatment for many HIV-infected individuals. The tolerability, pill burden and efficacy associated with this class of agents make them a frequent choice for first-line therapy. Here we review nevirapine and efavirenz in terms of efficacy, resistance and toxicity, focusing particularly on the use of nevirapine to prevent mother-to-child transmission in developing countries.

Tuberculosis immune reconstitution inflammatory syndrome in countries with limited resources

Mycobacterium tuberculosis infection accounts for probably one third of human immunodeficiency virus (HIV) related immune reconstitution inflammatory syndrome (IRIS) events, particularly in developing countries where HIV and tuberculosis (TB) co-infection is very common. Small cohort studies of HIV-positive patients with active TB treated with antiretroviral therapy (ART) suggest an incidence of TB IRIS varying between 11% and 45%. Risk factors for TB IRIS that have been suggested in certain studies but not in others include: starting ART within 6 weeks of starting TB treatment; extra-pulmonary or disseminated disease; a low CD4+ lymphocyte count and a high viral load at the start of ART; and a good immunological and virological response during highly active antiretroviral therapy (HAART). It is important to agree on a clinical case definition of TB IRIS that could be used in resource-limited settings. Such a case definition could be used to determine the exact incidence and consequences of TB IRIS and would be valuable worldwide in clinical trials that are needed to answer questions on how this phenomenon could be prevented and treated.