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Osmotic swelling and residual stress are increasingly recognized as important factors in soft tissue biomechanics. Little attention has been given to residual stress in periodontal ligament (PDL) biomechanics despite its rapid growth and remodeling potential. Those tissues that bear compressive loads, e.g., articular cartilage, intervertebral disk, have received much attention related to their capacities for osmotic swelling. To understand residual stress and osmotic swelling in the PDL, it must be asked (1) to what extent, if any, does the PDL exhibit residual stress and osmotic swelling, and (2) if so, whether residual stress and osmotic swelling are mechanically significant to the PDL’s stress/strain behavior under external loading. Here, we incrementally built a series of computer models that were fit to uniaxial loading, osmotic swelling and residual stretch data. The models were validated with in vitro shear tests and in vivo tooth-tipping data. Residual stress and osmotic swelling models were used to analyze tension and compression stress (principal stress) effects in PDL specimens under external loads. Shear-to-failure experiments under osmotic conditions were performed and modeled to determine differences in mechanics and failure of swollen periodontal ligament. Significantly higher failure shear stresses in swollen PDL suggested that osmotic swelling reduced tension and thus had a strengthening effect. The in vivo model’s first and third principal stresses were both higher with residual stress and osmotic swelling, but smooth stress gradients prevailed throughout the three-dimensional PDL anatomy. The addition of PDL stresses from residual stress and osmotic swelling represents a unique concept in dental biomechanics.

A new class of PDE4 inhibitors were designed and synthesized via the InCl3 mediated heteroarylation of indoles and their further derivatization through the Pd(II)-catalyzed C H activation strategy. This effort allowed us to discover a series of 2-(1H-indol-3-yl)-quinoxaline based inhibitors possessing PDE4B selectivity over PDE4D and PDE4C. One of these compounds i.e. 3b (PDE4B IC50 = 0.39 ± 0.13 μM with ∼27 and > 250 fold selectivity for PDE4B over PDE4D and C, respectively) showed effects in Zebrafish experimental autoimmune encephalomyelitis (EAE) model of multiple sclerosis when dosed at 3, 10 and 30 mg/kg intraperitoneally. Indeed, it halted the progression of the disease across all these doses tested. At an intraperitoneal dose of 30 mg/kg the compound 3b showed promising effects in adjuvant induced arthritic rats. The compound reduced paw volume, inflammation and pannus formation (in the knee joints) as well as pro-inflammatory gene expression/mRNA levels significantly in arthritic rats. Moreover, this compound was found to be selective towards PDE4 over other families of PDEs in vitro and safe when tested for its probable toxicity (e.g. teratogenicity, hepatotoxicity and cardiotoxicity) in Zebrafish.

Rectal mucinous adenocarcinoma (MAC) is a relatively uncommon type of rectal cancer, characterized by abundant extracellular mucin. At the time of presentation, they are found to be at an advanced stage and hence are difficult to treat and usually carry a poor prognosis. We report a case of rectal MAC with an unusual early presentation for which laparoscopic abdominoperineal resection was performed.

Background: In the era of evidence-based health care, protocol of intervention in traumatic brain injury (TBI) cases help decide more easily and safely about patients and prevent unnecessary transfer of patients to other centers. Objectives: The objective of this study is to provide protocol-based intervention and evaluate the epidemiological, clinical characteristics of TBI cases. Methods: This prospective study was conducted on 704 patients who were suspected of TBI at the Department of Neurosurgery, Narayana Medical College and Hospital, followed by protocol-based intervention assessed and reassessed repeatedly. Results: Overall, TBI involved 569 (80.82%) adults in the productive age groups (21–60 years); among males 81.47%. Among males, highest (23.15%) cases were in the age group of 31–40 years while in females, majority (27.04%) was among 41–50 years. Road traffic accidents were the most common (54.12%) mechanism of injury followed by fall (21.31%) and two-wheelers (15.20%). More than half sustained mild TBI (51.42%) while 26.28% moderate TBI and 22.30% severe TBI; among males, severe TBI victims 102 (18.82%) were in the productive age group. Loss of consciousness was almost a universal and significant observation (95.45%); vomiting was next common finding (76.42%). Bleeding from the ear-nose-throat (ENT) region was more in males (33.58%) than females (20.75%). Glasgow coma scale was significantly related with loss of consciousness (91.08%), vomiting (63.06%), and ENT bleeding (44.59%) in severe, moderate, and mild injuries. Conclusion: A rational clinical acumen with judicious use of diagnostic protocol leads to better management of TBI without unnecessary imaging and thus reduce total health-care costs.

Background: Acute Computerized Tomography (CT) characteristics are used widely and most accepted for prediction of outcome among Traumatic Brain Injury (TBI). The commonly available and simple combinations of existing and unexplored CT parameters may be more useful in prediction of outcome. The present study explores commonly available CT characteristics by possible combinations based on anatomical basics.Methods: Abnormal CT sign was considered with any cranial lesion. Based on anatomical locations of cortical lobes, nine possibilities were made that include individual and combinations of mentioned lobes. The laterality was either right or left or bilateral. The outcome was favourable or unfavourable based on discharge Glasgow Outcome Scale (GOS). Binary logistic regression was used to predict outcome.Results: 452 patients were recruited in the present study. There was significant risk of unfavourable outcome among patients with location of Sub Dural Haemorrhage (SDH) in Parietal + Temporal region (OR=10,pConclusion: The present study based on anatomical classification has shown that location and laterality of lesion can significantly predict TBI outcome.

Chronic inflammatory diseases such as insulin resistance, Type 2 diabetes, neurodegenerative diseases etc., are shown to be caused due to imbalanced activation states of macrophages. MicroRNAs which are transcriptional/post-transcriptional regulators of gene expression drive several pathophysiological processes including macrophage polarization. However the functional role of microRNAs in regulating inflammation induced insulin resistance is ill defined. In our current study we observed that the expression of miR-712 was reduced in macrophages exposed to LPS and IFN-γ. Ectopic expression of miR-712 in RAW 264.7 mouse macrophages impaired the expression of iNOS protein and secretion of pro-inflammatory cytokines such as TNF-α, IL-6 and IFN-β which in turn led to improved insulin stimulated glucose uptake in co-cultured L6 myoblasts. Mechanistically, we identified that miR-712 targets the 3'UTR of a potent inflammatory gene LRRK2 and dampens the phosphorylation of p38 and ERK1/2 kinases. Taken together, our data underscore the regulatory role of miR-712 in restoring insulin stimulated glucose uptake by myoblasts through down-regulating macrophage mediated inflammatory responses.

This study investigates how APOE modulates neuronal function integrity during normal aging and in the context of amyloidosis. This work demonstrates that APOE is a necessary partner of Aβ-dependent neuronal dysfunction and synaptotoxicity but also preserves neuronal network during aging., Apolipoprotein E (APOE) effects on brain function remain controversial. Removal of APOE not only impairs cognitive functions but also reduces neuritic amyloid plaques in mouse models of Alzheimer’s disease (AD). Can APOE simultaneously protect and impair neural circuits? Here, we dissociated the role of APOE in AD versus aging to determine its effects on neuronal function and synaptic integrity. Using two-photon calcium imaging in awake mice to record visually evoked responses, we found that genetic removal of APOE improved neuronal responses in adult APP/PSEN1 mice (8–10 mo). These animals also exhibited fewer neuritic plaques with less surrounding synapse loss, fewer neuritic dystrophies, and reactive glia. Surprisingly, the lack of APOE in aged mice (18–20 mo), even in the absence of amyloid, disrupted visually evoked responses. These results suggest a dissociation in APOE’s role in AD versus aging: APOE may be neurotoxic during early stages of amyloid deposition, although being neuroprotective in latter stages of aging.

Introduction In this article, we describe our experience of using Rotterdam computed tomography (CT) score at index admission to predict the outcome in traumatic brain injury (TBI) patients. Materials and Methods A total of 370 TBI patients admitted to the Neurosurgery Intensive Care Unit, Narayana Medical College and Hospital, Andhra Pradesh, between January 2014 and December 2014 were evaluated. Based on availability of emergency CT scan, these patients' charts were reviewed prospectively. CT scan findings were quantified using Rotterdam CT classification (basal cistern, midline shift, and intraventricular blood/subarachnoid blood). Patient characteristic, Glasgow Coma Scale (GCS) score, Rotterdam CT classification, and outcome were analyzed. Correlation between Rotterdam CT classification at index admission and outcome at discharge from the hospital, alive or dead, was assessed. Results The mean age of patients was 39.19 ± 15.18 years. Rotterdam CT score was significant ( p p = 0.618). The outcome and individual components of Rotterdam CT classification were statistically significant. Conclusion Increase in Rotterdam CT score was significantly associated with mortality at discharge. We suggest that it is possible to predict the outcome based on CT scan findings. However, the findings can have shortcomings, due to obvious reasons.

Objective Migraine is one of the most common and debilitating neurological conditions. Familial hemiplegic migraine type 1 (FHM1), a monogenic migraine subtype, is caused by gain-of-function of voltage-gated CaV2.1 calcium channels. FHM1 mice carry human pathogenic mutations in the α1A subunit of CaV2.1 channels and are highly susceptible to cortical spreading depression (CSD), the electrophysiologic event underlying migraine aura. To date, however, the mechanism underlying increased CSD/migraine susceptibility remains unclear.

Background Amyloid-β oligomers (oAβ) are thought to mediate neurotoxicity in Alzheimer’s disease (AD), and previous studies in AD transgenic mice suggest that calcium dysregulation may contribute to these pathological effects. Even though AD mouse models remain a valuable resource to investigate amyloid neurotoxicity, the concomitant presence of soluble Aβ species, fibrillar Aβ, and fragments of amyloid precursor protein (APP) complicate the interpretation of the phenotypes. Method To explore the specific contribution of soluble oligomeric Aβ (oAβ) to calcium dyshomeostasis and synaptic morphological changes, we acutely exposed the healthy mouse brain, at 3 to 6 months of age, to naturally occurring soluble oligomers and investigated their effect on calcium levels using in vivo multiphoton imaging. Results We observed a dramatic increase in the levels of neuronal resting calcium, which was dependent upon extracellular calcium influx and activation of NMDA receptors. Ryanodine receptors, previously implicated in AD models, did not appear to be primarily involved using this experimental setting. We used the high resolution cortical volumes acquired in-vivo to measure the effect on synaptic densities and observed that, while spine density remained stable within the first hour of oAβ exposure, a significant decrease in the number of dendritic spines was observed 24 h post treatment, despite restoration of intraneuronal calcium levels at this time point. Conclusions These observations demonstrate a specific effect of oAβ on NMDA-mediated calcium influx, which triggers synaptic collapse in vivo. Moreover, this work leverages a method to quantitatively measure calcium concentration at the level of neuronal processes, cell bodies and single synaptic elements repeatedly and thus can be applicable to testing putative drugs and/or other intervention methodologies. Electronic supplementary material The online version of this article (doi:10.1186/s13024-017-0169-9) contains supplementary material, which is available to authorized users.

Alzheimer's disease (AD) is pathologically characterized by the deposition of extracellular amyloid-β plaques and intracellular aggregation of tau protein in neurofibrillary tangles (NFTs) (1, 2). Progression of NFT pathology is closely correlated with both increased neurodegeneration and cognitive decline in AD (3) and other tauopathies, such as frontotemporal dementia (4, 5). The assumption that mislocalization of tau into the somatodendritic compartment (6) and accumulation of fibrillar aggregates in NFTs mediates neurodegeneration underlies most current therapeutic strategies aimed at preventing NFT formation or disrupting existing NFTs (7, 8). Although several disease-associated mutations cause both aggregation of tau and neurodegeneration, whether NFTs per se contribute to neuronal and network dysfunction in vivo is unknown (9). Here we used awake in vivo two-photon calcium imaging to monitor neuronal function in adult rTg4510 mice that overexpress a human mutant form of tau (P301L) and develop cortical NFTs by the age of 7-8 mo (10). Unexpectedly, NFT-bearing neurons in the visual cortex appeared to be completely functionally intact, to be capable of integrating dendritic inputs and effectively encoding orientation and direction selectivity, and to have a stable baseline resting calcium level. These results suggest a reevaluation of the common assumption that insoluble tau aggregates are sufficient to disrupt neuronal function.

Amyloid beta (Abeta)-containing plaques are surrounded by dystrophic neurites in the Alzheimer's disease (AD) brain, but whether and how plaques induce these neuritic abnormalities remain unknown. We tested the hypothesis that soluble oligomeric assemblies of Abeta, which surround plaques, induce calcium-mediated secondary cascades that lead to dystrophic changes in local neurites. We show that soluble Abeta oligomers lead to activation of the calcium-dependent phosphatase calcineurin (CaN) (PP2B), which in turn activates the transcriptional factor nuclear factor of activated T cells (NFAT). Activation of these signaling pathways, even in the absence of Abeta, is sufficient to produce a virtual phenocopy of Abeta-induced dystrophic neurites, dendritic simplification, and dendritic spine loss in both neurons in culture and in the adult mouse brain. Importantly, the morphological deficits in the vicinity of Abeta deposits in a mouse model of AD are ameliorated by CaN inhibition, supporting the hypothesis that CaN-NFAT are aberrantly activated by Abeta and that CaN-NFAT activation is responsible for disruption of neuronal structure near plaques. In accord with this, we also detect increased levels of an active form of CaN and NFATc4 in the nuclear fraction from the cortex of patients with AD. Thus, Abeta appears to mediate the neurodegeneration of AD, at least in part, by activation of CaN and subsequent NFAT-mediated downstream cascades.

Although senile plaques focally disrupt neuronal health, the functional response of astrocytes to Alzheimer's disease pathology is unknown. Using multiphoton fluorescence lifetime imaging microscopy in vivo, we quantitatively imaged astrocytic calcium homeostasis in a mouse model of Alzheimer's disease. Resting calcium was globally elevated in the astrocytic network, but was independent of proximity to individual plaques. Time-lapse imaging revealed that calcium transients in astrocytes were more frequent, synchronously coordinated across long distances, and uncoupled from neuronal activity. Furthermore, rare intercellular calcium waves were observed, but only in mice with amyloid-β plaques, originating near plaques and spreading radially at least 200 micrometers. Thus, although neurotoxicity is observed near amyloid-β deposits, there exists a more general astrocyte-based network response to focal pathology.

Tularemia is a zoonotic disease caused by the Gram-negative intracellular pathogen Francisella tularensis. These bacteria evade phagolysosomal fusion, escape from the phagosome and replicate in the host cell cytoplasm. IFNgamma has been shown to suppress the intra-macrophage growth of Francisella through both nitric oxide-dependent and -independent pathways. Since Francisella is known to subvert host immune responses, we hypothesized that this pathogen could interfere with IFNgamma signaling. Here, we report that infection with Francisella suppresses IFNgamma-induced STAT1 expression and phosphorylation in both human and murine mononuclear phagocytes. This suppressive effect of Francisella is independent of phagosomal escape or replication and is mediated by a heat-stable and constitutively expressed bacterial factor. An analysis of the molecular mechanism of STAT1 inhibition indicated that expression of SOCS3, an established negative regulator of IFNgamma signaling, is highly up-regulated during infection and suppresses STAT1 phosphorylation. Functional analyses revealed that this interference with IFNgamma signaling is accompanied by the suppression of IP-10 production and iNOS induction resulting in increased intracellular bacterial survival. Importantly, the suppressive effect on IFNgamma-mediated host cell protection is most effective when IFNgamma is added post infection, suggesting that the bacteria establish a permissive environment within the host cell.

Alzheimer's disease is characterized by the deposition of senile plaques and progressive dementia. The molecular mechanisms that couple plaque deposition to neural system failure, however, are unknown. Using transgenic mouse models of AD together with multiphoton imaging, we measured neuronal calcium in individual neurites and spines in vivo using the genetically encoded calcium indicator Yellow Cameleon 3.6. Quantitative imaging revealed elevated [Ca(2+)]i (calcium overload) in approximately 20% of neurites in APP mice with cortical plaques, compared to less than 5% in wild-type mice, PS1 mutant mice, or young APP mice (animals without cortical plaques). Calcium overload depended on the existence and proximity to plaques. The downstream consequences included the loss of spinodendritic calcium compartmentalization (critical for synaptic integration) and a distortion of neuritic morphologies mediated, in part, by the phosphatase calcineurin. Together, these data demonstrate that senile plaques impair neuritic calcium homeostasis in vivo and result in the structural and functional disruption of neuronal networks.

Functional magnetic resonance imaging (fMRI) studies were performed for visualizing ongoing brain plasticity in Neurotrophin-3 (NT3)-treated experimental spinal cord injury (SCI). In response to the electrical stimulation of the forepaw, the NT3-treated animals showed extensive activation of brain structures that included contralateral cortex, thalamus, caudate putamen, hippocampus, and periaqueductal gray. Quantitative analysis of the fMRI data indicated significant changes both in the volume and center of activations in NT3-treated animals relative to saline-treated controls. A strong activation in both ipsi- and contralateral periaqueductal gray and thalamus was observed in NT3-treated animals. These studies indicate ongoing brain reorganization in the SCI animals. The fMRI results also suggest that NT3 may influence nociceptive pathways.

The mechanisms underlying inflammation induced insulin resistance are poorly understood. Here, we report that the expression of PIMT, a transcriptional co-activator binding protein, was up-regulated in the soleus muscle of high sucrose diet (HSD) induced insulin resistant rats and TNF-α exposed cultured myoblasts. Moreover, TNF-α induced phosphorylation of PIMT at the ERK1/2 target site Ser298. Wild type (WT) PIMT or phospho-mimic Ser298Asp mutant but not phospho-deficient Ser298Ala PIMT mutant abrogated insulin stimulated glucose uptake by L6 myotubes and neonatal rat skeletal myoblasts. Whereas, PIMT knock down relieved TNF-α inhibited insulin signaling. Mechanistic analysis revealed that PIMT differentially regulated the expression of GLUT4, MEF2A, PGC-1α and HDAC5 in cultured cells and skeletal muscle of Wistar rats. Further characterization showed that PIMT was recruited to GLUT4, MEF2A and HDAC5 promoters and overexpression of PIMT abolished the activity of WT but not MEF2A binding defective mutant GLUT4 promoter. Collectively, we conclude that PIMT mediates TNF-α induced insulin resistance at the skeletal muscle via the transcriptional modulation of GLUT4, MEF2A, PGC-1α and HDAC5 genes.

Uncontrolled inflammation leads to several diseases such as insulin resistance, T2D and several types of cancers. The functional role of microRNAs in inflammation induced insulin resistance is poorly studied. MicroRNAs are post-transcriptional regulatory molecules which mediate diverse biological processes. We here show that miR-16 expression levels are down-regulated in different inflammatory conditions such as LPS/IFNγ or palmitate treated macrophages, palmitate exposed myoblasts and insulin responsive tissues of high sucrose diet induced insulin resistant rats. Importantly, forced expression of miR-16 in macrophages impaired the production of TNF-α, IL-6 and IFN-β leading to enhanced insulin stimulated glucose uptake in co-cultured skeletal myoblasts. Further, ectopic expression of miR-16 enhanced insulin stimulated glucose uptake in skeletal myoblasts via the up-regulation of GLUT4 and MEF2A, two key players involved in insulin stimulated glucose uptake. Collectively, our data highlight the important role of miR-16 in ameliorating inflammation induced insulin resistance.

Functional MRI (fMRI) on spinal cord-injured rodents at 4 and 8 weeks post injury (PI) is described. The paradigm for fMRI, based on electrical stimulation of rat paws, was automated using an in-house designed microprocessor-based controller that was interfaced to a stimulator. The MR images were spatially normalized to the Paxinos and Watson atlas using publicly available digital images of the cryosections. In normal uninjured animals, the activation was confined to the contralateral somatosensory cortex. In contrast, in injured animals, extensive activation, which included structures such as ipsilateral cortex, thalamus, hippocampus, and the caudate putamen, was observed at 4 and 8 weeks PI. Quantitative cluster analysis was carried out to calculate the volumes and centers of activation in individual brain structures. Based on this analysis, significant increase in activation between 4 and 8 weeks was observed only in the ipsilateral caudate putamen and thalamus. These studies suggest extensive and ongoing brain reorganization in spinal cord-injured animals.

Metastasis is responsible for most cancer deaths. A better under standing of the process provides opportunities to develop new treatments to prevent metastasis. This article summarizes findings from experimental in vivo videomicroscopy and quantitative studies on metastatic inefficiency, which indicate that early steps in hematogenous metastasis may be quite efficient, but that regulation of cancer cell growth in secondary sites determines metastatic outcome. The authors have identified three key stages of this growth regulation: survival of a subset of single cells, proliferation of a subset of these cells to form preangiogenic micrometastases, and persistence of growth of a subset of these to form vascularized metastases. Formation of clinically relevant metastases is determined by the proportion of cells that proceeds successfully through each stage, and surviving single cells and preangiogenic micrometastases both represent possible sources of tumor dormancy.

Stump appendicitis is a rare complication reported both after laparoscopic and open appendectomy. Diagnosis of the condition is usually delayed because of previous history of appendectomy and adequate clinical vigilance on part of treating surgeon is required. It results from incomplete appendectomy. Stump appendicitis is inflammation of residual appendix after appen dectomy and has reported incidence of 1 in 50,000. We report a case of 20-year-old male who underwent open appendectomy 7 years back and now presented with features of abdominal wall abscess. The patient was diagnosed with stump appendicitis and laparoscopic completion appendectomy was done.

Tuberculosis (TB) caused by Mycobacterium tuberculosis (Mtb) has emerged as one of the deadliest of bacterial communicable diseases faced by mankind. According to the 2014 WHO report, nine million new cases of TB and 0.36 million deaths including HIV positive cases were recorded1. Despite the availability of antibiotics, childhood vaccine and advances in understanding the biology of Mtb and the host immune responses to this stealth pathogen, this Mycobacterium continues to present an insurmountable challenge. Emergence of drug resistant strains of Mtb threatens the effectiveness of the disease control programmes in India and other countries2. M. tuberculosis lacks resistance plasmids and does not acquire drug resistance through horizontal gene transfer. Intrinsic drug resistance is primarily due to the limited penetration of the thick, lipid rich cell wall of Mtb by the antibiotics. While the mechanism of multidrug resistance remains elusive, recent evidences suggest that multiple mechanisms are exploited by the bacterium3. Moreover, drug modifying or inactivating enzymes and efflux pumping mechanisms have also been reported3,4,5. Clinically relevant resistance to Mtb results from the acquisition of spontaneous mutations including novel mutations in rpoB, katG, inhA, gyrA and gyrB loci and the selection of the mutants by the drug treatment to which the resistance has originated6,7. A better understanding of the mechanistic basis of drug resistance will be potentially important in designing new treatment strategies for multidrug resistant (MDR)-TB. The article by Singh et al8 in this issue identifies important changes in the proteome of multidrug resistant tuberculosis caused due to non-compliance with the standard chemotherapy. The authors performed proteomic analysis of the sequential clinical isolates of Mtb from a 22 yr old “treatment non-compliant” male patient and identified 27 proteins that were upregulated in the drug resistant clinical isolates. Importantly, Singh et al8 observed that five different protein spots representing chaperonin protein dnaK HSP70 (2 spots), hypothetical protein Rv2004, antigen 84 (wag31) and bfrA were consistently upregulated in all the three drug resistant isolates examined. Among the 27 proteins up- regulated in drug resistant isolates, about 30 per cent of the proteins have roles in intermediary metabolism and respiration function, as per TubercuList database (http://tuberculist.epfl.ch/). Expectedly, the protein levels of drug pressure responsive chaperonin proteins dnaK HSP70 (Rv350) and groEL2 (Rv440) were elevated in the drug resistant isolates9. M. tuberculosis aconitase (Rv1475c), another protein identified by Singh and his colleagues, was earlier shown to be a bifunctional enzyme10 with roles in tricarboxylic acid (TCA) cycle, and also displayed the ability to respond to iron levels by binding to both mycobacterial and mammalian transcripts harbouring iron responsive elements. Interestingly, their observation that Rv1475c protein is specifically over-expressed in Mtb clinical isolate resistant to rifampicin, isoniazid, ethambutol and kanamcyin points to a link between iron homeostasis and development of MDR in tuberculosis11. The glycogen accumulation regulator protein GarA, another protein found to be upregulated in drug resistant isolates by Singh et al8, was earlier reported to have a key role in TCA cycle and glutamate metabolism and was required for intracellular growth of Mtb in macrophages12. Consistent with the elevated GarA levels, the glycogen levels in all the three drug resistant isolates were enhanced after seven days of culture. Mtb growth regulator, Wag31 (Rv2145c), also found to be overexpressed at both transcript and protein levels in drug resistant clinical isolates, was consistent with a previous study13. The observed difference in mobility of Wag31 between sensitive and resistant isolates points to the role of post-translational protein modifications. Another important aspect of this study was that drug resistance information was derived from the proteomic analysis of sequential clinical isolates from a single tuberculosis patient with increasing resistance to standard chemotherapy. Such analysis is likely to provide more realistic information than data obtained from the drug resistant strains developed in the laboratory. This will also help identify the mutations acquired by Mtb due to increasing drug resistance rather than merely highlighting the differences caused due to genotype-environment interaction as in the case of drug resistant Mtb isolates from multiple individuals. While the identification of eight hypothetical proteins overexpressed in drug resistant clinical isolates is significant, ascribing a function(s) to them, particularly in the context of development of multidrug resistance, would have important implications. The data presented in this study should be interpreted with circumspect. As rightly acknowledged by the authors, the overexpression of several proteins observed in this study may not be exclusively due to the increasing drug resistance but could be a result of host specific stress or extended growth period in the patient or a combination of both. The overexpression of chaperonin protein dnaK HSP70 lends support to such an argument. The technical problems, including sensitivity and resolution issues, encountered by these investigators also raise questions about the truly representative proteome profile of the MDR isolates. Considering the growing incidences of extensively drug resistant (XDR)-TB in India, it is imperative to carry out more such studies with sequential multidrug resistant clinical isolates, for such information will likely not only provide important mechanistic cues for the development of novel anti-tuberculosis drugs in future but could also serve as potential biomarker for drug resistance and dormancy.

Previous clinical studies have documented a close relationship between cerebrovascular disease and risk of Alzheimer's disease. We examined possible mechanistic interactions through use of experimental stroke models in a transgenic mouse model of β-amyloid deposition (APPswe/PS1dE9). Following middle cerebral artery occlusion, we observed a rapid increase in amyloid plaque burden in the region surrounding the infarction. In human tissue samples, however, we were unable to detect a localized increase in amyloid burden adjacent to cerebral infarcts. To resolve this discrepancy, we generated cerebral microstrokes in amyloid precursor protein mouse models with the photosensitive dye Rose bengal, and monitored plaque formation in real time using multiphoton microscopy. We observed a striking increase in the number of new plaques and amyloid angiopathy in the area immediately surrounding the infarcted area; however, the effect was transient, potentially resolving the discord between mouse and human tissue. We did not detect changes in candidate proteins related to β-amyloid generation or degradation such as β-amyloid-converting enzyme, amyloid precursor protein, presenilin 1, neprylisin or insulin-degrading enzyme. Together, these results demonstrate that strokes can trigger accelerated amyloid deposition, most likely through interference with amyloid clearance pathways. Additionally, this study indicates that focal ischaemia provides an experimental paradigm in which to study the mechanisms of plaque seeding and growth.

Background Delay in diagnosis of pulmonary tuberculosis results in increasing severity, mortality and transmission. Various investigators have reported about delays in diagnosis of tuberculosis. We aimed at summarizing the data on these delays in diagnosis of tuberculosis. Methods A systematic review of literature was carried out. Literature search was done in Medline and EMBASE from 1990 to 2008. We used the following search terms: delay, tuberculosis, diagnosis, and help-seeking/health-seeking behavior without language restrictions. In addition, indices of four major tuberculosis journals were hand-searched. Subject experts in tuberculosis and authors of primary studies were contacted. Reference lists, review articles and text book chapters were also searched. All the studies were assessed for methodological quality. Only studies carried out on smear/culture-positive tuberculosis patients and reporting about total, patient and health-care system delays were included. Results A total of 419 potential studies were identified by the search. Fifty two studies qualified for the review. The reported ranges of average (median or mean) total delay, patient delay, health system delay were 25–185 days, 4.9–162 days and 2–87 days respectively for both low and high income countries. Average patient delay was similar to health system delay (28.7 versus 25 days). Both patient delay and health system delay in low income countries (31.7 days and 28.5 days) were similar to those reported in high income countries (25.8 days and 21.5 days). Conclusion The results of this review suggest that there is a need for revising case-finding strategies. The reported high treatment success rate of directly observed treatment may be supplemented by measures to shorten the delay in diagnosis. This may result in reduction of infectious cases and better tuberculosis control.

Francisella tularensis, the causative agent of tularemia, is phagocytosed by immune cells such as monocytes and macrophages. Instead of being destroyed in the phagolysosome, the bacterium escapes the phagosome and replicates within the host cytosol. Recent studies indicate that phagosomal escape may have a major impact on the nature of the inflammatory cytokine response to infection. To better understand the host cell response to Francisella infection, we exposed human peripheral blood monocytes to Francisella novicida and analyzed transcriptional changes using high-density oligonucleotide microarrays. Results showed a nearly 300-fold up-regulation of transcripts for the p19 subunit of IL-23, and a nearly 18-fold up-regulation for the p40 subunit of IL-12. IL-23 is formed by the heterodimerization of p19 and p40, and is an important cytokine of the innate immune response. Up-regulation of p19 and p40 was confirmed at the protein level by Western blotting and ELISA analyses, and was found to be largely dependent on PI3K and NF-κB activity. Studies using medium from infected monocytes with or without a p19 blocking Ab showed that the secreted IL-23 induced IFN-γ production from NK cells, suggesting a potential biologically important role for IL-23 in host defense. Finally, infection of human monocytes by the highly virulent Francisella SCHU S4 strain likewise led to IL-23 production, suggesting that the IL-23 response may be relevant during tularemia.

Amyotrophic Lateral sclerosis (ALS) is a disease characterized by pure motor asymmetric wasting of various muscles with associated upper motor neuron signs. The split hand sign, which is because of dissociated muscle weakness in the hands (thenar muscles disproportionately wasted as compared to the hypothenar muscles) is a useful clinical sign for bed side diagnosis of ALS.

Background Studies from developed countries have reported on host-related risk factors for extra-pulmonary tuberculosis (EPTB). However, similar studies from high-burden countries like Nepal are lacking. Therefore, we carried out this study to compare demographic, life-style and clinical characteristics between EPTB and PTB patients. Methods A retrospective analysis was carried out on 474 Tuberculosis (TB) patients diagnosed in a tertiary care hospital in western Nepal. Characteristics of demography, life-style and clinical features were obtained from medical case records. Risk factors for being an EPTB patient relative to a PTB patient were identified using logistic regression analysis. Results The age distribution of the TB patients had a bimodal distribution. The male to female ratio for PTB was 2.29. EPTB was more common at younger ages (< 25 years) and in females. Common sites for EPTB were lymph nodes (42.6%) and peritoneum and/or intestines (14.8%). By logistic regression analysis, age less than 25 years (OR 2.11 95% CI 1.12–3.68) and female gender (OR 1.69, 95% CI 1.12–2.56) were associated with EPTB. Smoking, use of immunosuppressive drugs/steroids, diabetes and past history of TB were more likely to be associated with PTB. Conclusion Results suggest that younger age and female gender may be independent risk factors for EPTB in a high-burden country like Nepal. TB control programmes may target young and female populations for EPTB case-finding. Further studies are necessary in other high-burden countries to confirm our findings.

Intraneuronal neurofibrillary tangles (NFTs) - a characteristic pathological feature of Alzheimer's and several other neurodegenerative diseases - are considered a major target for drug development. Tangle load correlates well with the severity of cognitive symptoms and mouse models of tauopathy are behaviorally impaired. However, there is little evidence that NFTs directly impact physiological properties of host neurons. Here we used a transgenic mouse model of tauopathy to study how advanced tau pathology in different brain regions affects activity-driven expression of immediate-early gene Arc required for experience-dependent consolidation of long-term memories. We demonstrate in vivo that visual cortex neurons with tangles are as likely to express comparable amounts of Arc in response to structured visual stimulation as their neighbors without tangles. Probability of experience-dependent Arc response was not affected by tau tangles in both visual cortex and hippocampal pyramidal neurons as determined postmortem. Moreover, whole brain analysis showed that network-wide activity-driven Arc expression was not affected by tau pathology in any of the brain regions, including brain areas with the highest tangle load. Our findings suggest that intraneuronal NFTs do not affect signaling cascades leading to experience-dependent gene expression required for long-term synaptic plasticity.