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Publication
Journal: PLoS ONE
August/20/2008
Abstract
BACKGROUND
Tuberculous meningitis (TBM) is a devastating condition. The rapid instigation of appropraite chemotherapy is vital to reduce morbidity and mortality. However rapid diagnosis remains elusive; smear microscopy has extremely low sensitivity on cerebrospinal fluid (CSF) in most laboratories and PCR requires expertise with advanced infrastructure and has sensitivity of only around 60% under optimal conditions. Neither technique allows for the microbiological isolation of M. tuberculosis and subsequent drug susceptibility testing. We evaluated the recently developed microscopic observation drug susceptibility (MODS) assay format for speed and accuracy in diagnosing TBM.
RESULTS
Two hundred and thirty consecutive CSF samples collected from 156 patients clinically suspected of TBM on presentation at a tertiary referal hospital in Vietnam were enrolled into the study over a five month period and tested by Ziehl-Neelsen (ZN) smear, MODS, Mycobacterial growth Indicator tube (MGIT) and Lowenstein-Jensen (LJ) culture. Sixty-one samples were from patients already on TB therapy for >1day and 19 samples were excluded due to untraceable patient records. One hundred and fifty samples from 137 newly presenting patients remained. Forty-two percent (n = 57/137) of patients were deemed to have TBM by clinical diagnostic and microbiological criteria (excluding MODS). Sensitivity by patient against clinical gold standard for ZN smear, MODS MGIT and LJ were 52.6%, 64.9%, 70.2% and 70.2%, respectively. Specificity of all microbiological techniques was 100%. Positive and negative predictive values for MODS were 100% and 78.7%, respectively for HIV infected patients and 100% and 82.1% for HIV negative patients. The median time to positive was 6 days (interquartile range 5-7), significantly faster than MGIT at 15.5 days (interquartile range 12-24), and LJ at 24 days (interquartile range 18-35 days) (P<0.01).
CONCLUSIONS
We have shown MODS to be a sensitive, rapid technique for the diagnosis of TBM with high sensitivity, ease of performance and low cost (0.53 USD/sample).
Publication
Journal: Neurology
February/7/2006
Abstract
The authors examined the usefulness of nested PCR (N-PCR) to detect Mycobacterium tuberculosis (MTB) DNA in CSF for assessing the clinical course of tuberculous meningitis (TBM). N-PCR successfully detected MTB DNA in all nine CSF samples from patients with suspected TBM. During anti-tuberculosis treatments, N-PCR results converted from positive to negative, correlating with the improvement of the patient's clinical condition.
Publication
Journal: Clinical Infectious Diseases
July/1/2015
Abstract
BACKGROUND
The immunopathogenesis of tuberculosis-associated immune reconstitution inflammatory syndrome (IRIS) remains incompletely understood, and we know of only 1 disease site-specific study of the underlying immunology; we recently showed that Mycobacterium tuberculosis culture positivity and increased neutrophils in the cerebrospinal fluid (CSF) of patients with tuberculous meningitis (TBM) are associated with TBM-IRIS. In this study we investigated inflammatory mediators at the disease site in patients with TBM-IRIS.
METHODS
We performed lumbar puncture at 3-5 time points in human immunodeficiency virus (HIV)-infected patients with TBM (n = 34), including at TBM diagnosis, at initiation of antiretroviral therapy (ART) (day 14), 14 days after ART initiation, at presentation of TBM-IRIS, and 14 days thereafter. We determined the concentrations of 40 mediators in CSF (33 paired with blood) with Luminex or enzyme-linked immunosorbent assays. Findings were compared between patients who developed TBM-IRIS (n = 16) and those who did not (TBM-non-IRIS; n = 18).
RESULTS
At TBM diagnosis and 2 weeks after ART initiation, TBM-IRIS was associated with severe, compartmentalized inflammation in the CSF, with elevated concentrations of cytokines, chemokines, neutrophil-associated mediators, and matrix metalloproteinases, compared with TBM-non-IRIS. Patients with TBM-non-IRIS whose CSF cultures were positive for M. tuberculosis at TBM diagnosis (n = 6) showed inflammatory responses similar to those seen in patients with TBM-IRIS at both time points. However, at 2 weeks after ART initiation, S100A8/A9 was significantly increased in patients with TBM-IRIS, compared with patients with TBM-non-IRIS whose cultures were positive at baseline.
CONCLUSIONS
A high baseline M. tuberculosis antigen load drives an inflammatory response that manifests clinically as TBM-IRIS in most, but not all, patients with TBM. Neutrophils and their mediators, especially S100A8/A9, are closely associated with the central nervous system inflammation that characterizes TBM-IRIS.
Publication
Journal: Journal of Clinical Investigation
December/28/1978
Abstract
Cold-insoluble globulin (CIG), which is immunochemically indistinguishable from the fibroblast surface protein known as large external transformation-sensitive glycoprotein and fibronectin, was detected immunologically in connective tissue fractions from adult human lung. The fractions tested were (a) intact parenchyma, (b) acidic structural glycoproteins (ASG) extracted from lung parenchyma with 0.3 M acetic acid, and (c) isolated alveolar basement membrane (ABM). For comparison with ABM, preparations of human glomerular basement membrane and human trophoblast basement membrane (TBM) were tested. CIG was not detected in glomerular basement membrane but was present in large amounts in TBM. The CIG antigen could be solubilized from the parenchyma and from ABM by collagenase digestion which indicates that CIG occurs in lung connective tissue in association with collagen. Fibrinogen antigenic determinants were present in the ASG fraction, but the question of whether CIG and fibrin(ogen) are associated in lung connective tissue requires further study. When CIG was quantified by electroimmunoassay, intact lung parenchyma contained approximately equal to 0.4% CIG, ASG contained 3-4.5% CIG, ABM contained 0.1-0.9% CIG and TBM contained 1.5%-7.2% Cg. the evidence suggests that CIG is a chemical constituent of lung connective tissue matrix where it may influence the function of alveoli.
Authors
Publication
Journal: Neurology India
August/30/2004
Abstract
OBJECTIVE
A prospective study was carried out to evaluate the lumboperitoneal shunt procedure.
METHODS
Four hundred and nine patients having communicating hydrocephalus were selected for the procedure during a 10-year period from March 1992 to February 2002. The average follow-up was 45.34 months.
RESULTS
Tubercular meningitis (TBM)-related hydrocephalus was detected in 285 patients. Forty per cent of the patients were less than 15 years of age. Glasgow Coma Scale (GCS) of less than 8 was seen in 40% patients and 14.9% patients were in GCS 13-15. At the time of discharge 56.7% patients improved in their GCS to 13 -15 and 14.9% were in GCS 8 or less. The overall mortality was 5.13% and shunt-related mortality was seen in 2% patients. Shunt malfunction requiring revision was seen in 32 patients (7.8%) and the total number of shunt revisions was 44 (11%). Shunt infection was noted in 3.4% patients. CSF leak at the lumbar end occurred in 12 patients. Four patients required conversion of LP shunt to VP shunt.
CONCLUSIONS
Lumboperitoneal shunt is an effective shunting procedure in communicating hydrocephalus.
Publication
Journal: Frontiers in Human Neuroscience
May/21/2015
Abstract
Rehabilitative training has shown to improve significantly motor outcomes and functional walking capacity in patients with incomplete spinal cord injury (iSCI). However, whether performance improvements during rehabilitation relate to brain plasticity or whether it is based on functional adaptation of movement strategies remain uncertain. This study assessed training improvement-induced structural brain plasticity in chronic iSCI patients using longitudinal MRI. We used tensor-based morphometry (TBM) to analyze longitudinal brain volume changes associated with intensive virtual reality (VR)-augmented lower limb training in nine traumatic iSCI patients. The MRI data was acquired before and after a 4-week training period (16-20 training sessions). Before training, voxel-based morphometry (VBM) and voxel-based cortical thickness (VBCT) assessed baseline morphometric differences in nine iSCI patients compared to 14 healthy controls. The intense VR-augmented training of limb control improved significantly balance, walking speed, ambulation, and muscle strength in patients. Retention of clinical improvements was confirmed by the 3-4 months follow-up. In patients relative to controls, VBM revealed reductions of white matter volume within the brainstem and cerebellum and VBCT showed cortical thinning in the primary motor cortex. Over time, TBM revealed significant improvement-induced volume increases in the left middle temporal and occipital gyrus, left temporal pole and fusiform gyrus, both hippocampi, cerebellum, corpus callosum, and brainstem in iSCI patients. This study demonstrates structural plasticity at the cortical and brainstem level as a consequence of VR-augmented training in iSCI patients. These structural changes may serve as neuroimaging biomarkers of VR-augmented lower limb neurorehabilitation in addition to performance measures to detect improvements in rehabilitative training.
Publication
Journal: Journal of Virology
August/28/1979
Abstract
Genetic analyses have defined a single gene (src) as that portion of the avian sarcoma virus (ASV) genome which encodes the protein directly responsible for ASV-induced neoplastic transformation. We have recently identified the polypeptide product of the src gene of the Schmidt-Ruppin (SR) strain of ASV, a 60,000-dalton phosphoprotein designated pp60(src), and have further determined that pp60(src) acts as a protein kinase. Essential to the identification and characterization of the pp60(src) protein of SR-ASV was the use of serum (TBR serum) from rabbits bearing SR-ASV-induced tumors. TBR serum was, however, strain specific, recognizing pp60(src) from SR-ASV-transformed cells only. We report here that sera from marmosets bearing tumors induced by the Bryan or SR strains of ASV (TBM sera) contain antibody which precipitates the transforming gene product from cells transformed by the SR, Bryan, Prague, or Bratislava strains of ASV. In contrast, rabbits bearing tumors induced by either the Bratislava or Bryan strains of ASV, or hamsters with SR-ASV-induced tumors did not produce antibody to pp60(src) from any strain of ASV. The 60,000-dalton polypeptides immunoprecipitated with TBM serum from cells transformed by each of the above virus strains are phosphoproteins. One-dimensional peptide mapping by limited proteolysis revealed that the pp60(src) proteins are structurally very similar, but not identical. Furthermore, all of the viral pp60(src) proteins have an associated phosphotransferase activity. In addition to detecting the viral src proteins, TBM serum was able to immunoprecipitate an antigenically related protein from normal uninfected avian cells.
Publication
Journal: Journal of Neurology
January/25/2015
Abstract
Tuberculous meningitis (TBM) is a preventable and curable common health problem among African adults. Poor nutrition, poverty, household crowding, drug resistant tuberculosis (TB) strains, AIDS, and malfunctioning TB control programs are important risk factors. We conducted a systematic review and meta-analysis of published literature reporting case-fatalities of TBM among adults in African countries from 1970 till date. A PubMed search identified relevant papers. Employed terms include 'adult tuberculous meningitis' AND 'tuberculosis Africa'. PRISMA review guidelines were applied. Adult TBM case-fatalities, odds ratio (OR), relative risk (RR), forest-plot meta-analysis for weighted OR and RR, funnel plots, L'Abbé plots, meta-regressed bubble plots, and inter-study homogeneity were computed. Among 15 studies included, adult TBM occurred in up to 28 % of all meningitis forms with case-fatality of 60 % (inverse-variance weighted 54 %). Fixed-effect meta-analysis revealed weighted OR and RR of adult TBM fatalities to be 4.37 (95 % CI 3.92, 4.88) and 2.53 (95 % CI 2.38, 2.69), respectively. Inter-study homogeneity was reliable, regional representativeness was adequate allowing generalizability, and funnel-plots behaved symmetrically with insignificant inconsistency. All cases were initiated with anti-TB medication, while some had 'breakthrough' TBM. In Africa, adult TBM has a significant public health importance with a very high fatality which has remained stagnant for the past half-century. This reflects ongoing low quality of medical care at facilities where lengthy referrals end up. Community-based studies can reveal higher unaccounted morbidity, accrued disability, and larger mortality. Improving access points for early TB management at community-level, developing health infra-structure for comprehensive case management at facility-level, and poverty reduction can help combat this multi-faceted problem--whose reduction can in return help fight poverty.
Publication
Journal: European Journal of Radiology
February/9/2009
Abstract
OBJECTIVE
The aim of this study was to compare dynamic expiratory imaging and end-expiratory imaging using multi-detector CT (MDCT) of the central airways in patients suspected of tracheobronchomalacia (TBM).
METHODS
This study had local ethical committee approval. Seventy patients suspected of TBM were prospectively included. All patients underwent evaluation of central airways by three different low-dose MDCT acquisitions: end inspiration, end expiration, and dynamic expiration. Degree of airway collapse was measured by calculating the percentage change in the area and diameter of the airways between inspiratory and the two expiratory techniques at three levels of the trachea and in the sagittal diameter of the right and left main bronchi. Three threshold levels of percentage reduction in diameter or area (30%, 50%, and 70%) for defining TBM were evaluated.
RESULTS
In the entire population, the mean percentage of airway collapse was significantly greater with dynamic expiratory imaging than with the end-expiratory imaging at three different levels: lower thoracic trachea (26% vs. 16.6%, p<0.009), right (25.2% vs. 14%, p<0.01) and left main (24.7% vs. 13.3%, p<0.01) bronchus. Whatever the threshold value for defining TBM, dynamic expiratory imaging always resulted in diagnosing TBM in more patients than end-expiratory imaging.
CONCLUSIONS
Dynamic expiratory imaging shows a significantly greater degree and a significantly greater extent of airway collapse than standard end-expiratory imaging in patients suspected of TBM. Further evaluation of the clinical relevance of such findings is warranted.
Publication
Journal: Journal of Neurology
January/7/2016
Abstract
Predicting unfavorable outcome is of paramount importance in clinical decision making. Accordingly, we designed this multinational study, which provided the largest case series of tuberculous meningitis (TBM). 43 centers from 14 countries (Albania, Croatia, Denmark, Egypt, France, Hungary, Iraq, Italy, Macedonia, Romania, Serbia, Slovenia, Syria, Turkey) submitted data of microbiologically confirmed TBM patients hospitalized between 2000 and 2012. Unfavorable outcome was defined as survival with significant sequela or death. In developing our index, binary logistic regression models were constructed via 200 replicates of database by bootstrap resampling methodology. The final model was built according to the selection frequencies of variables. The severity scale included variables with arbitrary scores proportional to predictive powers of terms in the final model. The final model was internally validated by bootstrap resampling. A total of 507 patients' data were submitted among which 165 had unfavorable outcome. Eighty-six patients died while 119 had different neurological sequelae in 79 (16%) patients. The full model included 13 variables. Age, nausea, vomiting, altered consciousness, hydrocephalus, vasculitis, immunosuppression, diabetes mellitus and neurological deficit remained in the final model. Scores 1-3 were assigned to the variables in the severity scale, which included scores of 1-6. The distribution of mortality for the scores 1-6 was 3.4, 8.2, 20.6, 31, 30 and 40.1%, respectively. Altered consciousness, diabetes mellitus, immunosuppression, neurological deficits, hydrocephalus, and vasculitis predicted the unfavorable outcome in the scoring and the cumulative score provided a linear estimation of prognosis.
Publication
Journal: Pediatric Infectious Disease Journal
March/29/2015
Abstract
BACKGROUND
The World Health Organization recommends 12-month treatment (2RHZE/10RH) for children with tuberculous meningitis (TBM). Studies evaluating length of antituberculous treatment for TBM report similar completion and relapse rates comparing 6-month treatment with 12-month treatment.
METHODS
A prospective evaluation to determine whether short-course intensified treatment (6 RHZEth for HIV-infected and 9RHZEth for HIV-infected) is sufficient and safe in children with drug-susceptible TBM.
RESULTS
Of 184 children with TBM, median age 58 months and 90 (49%) male, 98 children (53%) presented at stage II TBM, 64 (35%) at stage III TBM and only 22 (12%) at stage I TBM. Ninety (49%) children were treated at home after the first month of therapy; all others received their full treatment in hospital. The HIV prevalence was 14% (22/155 children tested). Anti-TB drug-induced hepatotoxicity occurred in 5% (8 of 143 children tested), all tested negative for viral hepatitis; in all 8 cases, the original regimen was restarted without recurrence. After treatment completion, 147 (80%) children had a good outcome, 7 (3.8%) died. There was no difference in outcome between HIV-infected and HIV-uninfected children who completed treatment (P = 0.986) nor between TBM-hydrocephalic children who were medically treated or shunted (P = 0.166).
CONCLUSIONS
Short intensified treatment is safe and effective in both HIV-infected and HIV-uninfected children with drug-susceptible TBM.
Publication
Journal: Academic Radiology
October/26/2003
Abstract
OBJECTIVE
Investigators in this study compared standard-dose and low-dose inspiratory and expiratory computed tomographic (CT) images with regard to their usefulness for measuring the tracheal lumen in patients with or without tracheobronchomalacia (TBM). MATERIALS AND METHODS; Hospital records were reviewed to identify 10 consecutive patients with bronchoscopically proved TBM and 10 control subjects without TBM who underwent paired volumetric inspiratory and dynamic expiratory examinations with multisection CT. A low-dose (40-80 mA) technique was used for dynamic expiratory CT in 14 (70%) of the 20 subjects, and a standard dose (240-280 mA) was used in the remaining six (30%). All images were reviewed in a randomized, blinded fashion by two observers, who measured the tracheal lumen to determine the presence of TBM by consensus. The degree of confidence in measuring the tracheal lumen was graded on a four-point scale from 0(no confidence) to 3 (highest level of confidence), also by consensus of the two observers. Statistical analysis for differences in confidence level was performed with the Mann-Whitney U test. The image noise level was assessed by measuring the standard deviation of the presternal soft tissue, and statistical analysis for differences in noise level was performed with the t test.
RESULTS
The level of confidence in tracheal lumen measurement was high, regardless of respiratory phase and dose (inspiratory mean, 2.9; median, 3; range, 2-3; expiratory low-dose mean, 2.6; median, 3; range, 2-3; expiratory standard-dose mean, 2.8; median, 3; range, 2-3). There was no significant difference in confidence level between standard- and low-dose techniques (P = .53). Excessive central airway collapse (expiratory reduction in cross-sectional diameter,>> 50%) was seen in all 10 patients with TBM and in none of the control subjects.
CONCLUSIONS
The acquisition of paired inspiratory and dynamic expiratory images with multisection helical CT is a promising method for diagnosing TBM. The low-dose technique performs as well as the standard-dose technique for the dynamic expiratory phase, with a similar degree of confidence for measuring the tracheal lumen.
Publication
Journal: European Journal of Endocrinology
April/26/2010
Abstract
OBJECTIVE
To investigate the long-term effects of nasal continuous positive airway pressure (CPAP) ventilation in patients with obstructive sleep apnea syndrome (OSAS) on body composition (BC) and IGF1.
METHODS
Observational study.
METHODS
Seventy-eight (11 females and 67 males) OSAS patients who were compliant with CPAP (age 51+/-1.1 years) participated in the study. We assessed body mass index (BMI), total body mass (TBM), total body fat (TBF; kg) and lean body mass (LBM; kg), abdominal subcutaneous (SC) and visceral (V) fat (cm(2)), and waist circumference (WC; cm) by magnetic resonance imaging, and IGF1 (ng/ml) before and after 7.8+/-1.3 months of CPAP use of an average of 5.9+/-1.2 h.
RESULTS
Women had a higher BMI, WC; TBM, TBF, and more SC fat. Men had a higher LBM and more V fat. CPAP increased WC (+2.8+/-9.6 cm, P=0.02) and LBM (2.2+/-0.5 kg, P=0.006), but not IGF1. In men, CPAP increased BMI (0.5+/-0.2 kg/m(2), P=0.02), WC (1.7+/-6.9 cm, P=0.002), TBM (1.7+/-0.4 kg, P=0.0001), LBM (1.5+/-0.4 kg, P=0.0003), SC fat (12.9+/-5.1 cm(2), P=0.02), and IGF1 (13.6+/-4.2 ng/ml, P=0.002). Compliance with CPAP increased LBM in men aged <60 years, but not in those aged >60 years, and IGF1 increased in men aged 40-60 years only.
CONCLUSIONS
Long-term CPAP increased LBM in both sexes and IGF1 in men, while fat mass remained unchanged, suggesting a sexually dimorphic response of IGF1 to CPAP. The role of the GH axis activity and age to this response is unclear. The metabolic consequences of changes in LBM are still to be determined. Future studies on the effects of CPAP on BC should include LBM as an outcome.
Publication
Journal: PLoS ONE
July/4/2011
Abstract
OBJECTIVE
The diagnosis of tuberculous meningitis (TBM) in resource poor TB endemic environments is challenging. The accuracy of current tools for the rapid diagnosis of TBM is suboptimal. We sought to develop a clinical-prediction rule for the diagnosis of TBM in a high HIV prevalence setting, and to compare performance outcomes to conventional diagnostic modalities and a novel lipoarabinomannan (LAM) antigen detection test (Clearview-TB®) using cerebrospinal fluid (CSF).
METHODS
Patients with suspected TBM were classified as definite-TBM (CSF culture or PCR positive), probable-TBM and non-TBM.
RESULTS
Of the 150 patients, 84% were HIV-infected (median [IQR] CD4 count = 132 [54; 241] cells/µl). There were 39, 55 and 54 patients in the definite, probable and non-TBM groups, respectively. The LAM sensitivity and specificity (95%CI) was 31% (17;48) and 94% (85;99), respectively (cut-point ≥ 0.18). By contrast, smear-microscopy was 100% specific but detected none of the definite-TBM cases. LAM positivity was associated with HIV co-infection and low CD4 T cell count (CD4<200 vs. >200 cells/µl; p = 0.03). The sensitivity and specificity in those with a CD4<100 cells/µl was 50% (27;73) and 95% (74;99), respectively. A clinical-prediction rule ≥ 6 derived from multivariate analysis had a sensitivity and specificity (95%CI) of 47% (31;64) and 98% (90;100), respectively. When LAM was combined with the clinical-prediction-rule, the sensitivity increased significantly (p<0.001) to 63% (47;68) and specificity remained high at 93% (82;98).
CONCLUSIONS
Despite its modest sensitivity the LAM ELISA is an accurate rapid rule-in test for TBM that has incremental value over smear-microscopy. The rule-in value of LAM can be further increased by combination with a clinical-prediction rule, thus enhancing the rapid diagnosis of TBM in HIV-infected persons with advanced immunosuppression.
Publication
Journal: Pediatric Neurosurgery
January/22/2003
Abstract
Hydrocephalus is a common complication of tuberculous meningitis (TBM) in children. The aims of this study are to review our experience of hydrocephalus in childhood TBM and to evaluate the effect of the timing of ventriculoperitoneal shunting (VPS) on the final outcome. In this study, 156 patients with TBM and hydrocephalus were reviewed retrospectively between 1990 and 2000. Patients' ages ranged from 6 months to 15 years, with a mean age of 4.1 years. There were 85 boys, and the male-to-female ratio was 1.19:1.0. Sixty-two percent of the children were younger than 6 years old. VPS was performed 2 days after the diagnosis in 100 patients, and in the remaining 56 patients, 3 weeks after the diagnosis. The average follow-up period was 8.5 months. Good recovery or minor sequelae was seen in 82 patients (52.6%), and 51 died (12.3%). The timing of the VPS procedure and cerebral complications had an effect on the final outcome. Early VPS gave a better outcome in mild and moderate hydrocephalus (p = 0.040). This study has shown that early surgical procedure for mild/moderate hydrocephalus has a positive effect on the morbidity and mortality of hydrocephalus in childhood TBM (p = 0.014, p = 0.040, respectively). In severe hydrocephalus, there was a tendency for early shunting to have a positive effect on morbidity, although this did not reach statistical significance.
Publication
Journal: Journal of Experimental Medicine
July/31/1990
Abstract
CD34+ human marrow cells not expressing T cell-, B cell-, and myeloid cell-associated antigens (TBM-) were cloned by two-color cell sorting into culture wells containing irradiated marrow stromal cells. After 4 wk of culture, 3.7 +/- 2.1% of these cells generated colony-forming cells (CFC), with each of these cells generating 6.3 +/- 5.3 CFC. This was not due to the 0.5 +/- 0.5% CFC present in the purified CD34+ TBM- cells, as less than 1% of CFC persist in these cultures. This is the first demonstration that single immature precursor cells in human long-term cultures generate multiple CFC progeny. The immature nature of these clonable CD34+ TBM- precursors suggests their candidate status as human hematopoietic stem cells.
Publication
Journal: American Journal of Transplantation
July/20/2010
Abstract
Thrombomodulin (TBM) is an important vascular anticoagulant that has species specific effects. When expressed as a transgene in pigs, human (h)TBM might abrogate thrombotic manifestations of acute vascular rejection (AVR) that occur when GalT-KO and/or complement regulator transgenic pig organs are transplanted to primates. hTBM transgenic mice were generated and characterized to determine whether this approach might show benefit without the development of deleterious hemorrhagic phenotypes. hTBM mice are viable and are not subject to spontaneous hemorrhage, although they have a prolonged bleeding time. They are resistant to intravenous collagen-induced pulmonary thromboembolism, stasis-induced venous thrombosis and pulmonary embolism. Cardiac grafts from hTBM mice to rats treated with cyclosporine in a model of AVR have prolonged survival compared to controls. hTBM reduced the inflammatory reaction in the vein wall in the stasis-induced thrombosis and mouse-to-rat xenograft models and reduced HMGB1 levels in LPS-treated mice. These results indicate that transgenic expression of hTBM has anticoagulant and antiinflammatory effects that are graft-protective in murine models.
Publication
Journal: Journal of Immunology
April/22/1985
Abstract
The effector T cell repertoire in experimental interstitial nephritis was examined in a variety of susceptible and nonsusceptible mice. We observed that L3T4+ effector T cells in disease-susceptible mice disappear soon after immunization in preference to the emergence of Lyt-2+ effector cells. These latter cells respond with delayed-type hypersensitivity to tubular antigen in the context of H-2K. Such cells also express idiotypes (RE-Id) shared with kidney-bound alpha TBM-Ab that are regulated by an interactional effect of genes in Igh-1 and H-2K. These Lyt-2+ effector cells can be removed from renal infiltrates, and the transfer of similar cells under the renal capsule of naive mice results, within 5 days, in local interstitial nephritis. Nonsusceptible mice, however, not having these immune response genes, produce either L3T4+, Lyt-1+, RE-Id- effector T cells, which only respond to tubular antigen in the context of I-A, or Lyt-2+, RE-Id- T cells, which may lack very fine specificity. These findings suggest that susceptible mice carry a unique set of immune response genes that promote a T cell selection process that operates after induction, during the differentiation and development of disease-producing effector T cells.
Publication
Journal: Medical Science Monitor
February/19/2004
Abstract
BACKGROUND
Tuberculous meningitis (TBM) is a serious central nervous system infection, which is seen in clinical practice fairly frequently in developing and underdeveloped countries. Our study was intended to develop a reliable and rapid diagnostic methodology for detecting mycobacterium tuberculous bacilli (MTB) in cerebrospinal fluid (CSF). Dot Enzyme Linked Immunosorbent assay (Dot ELISA) has been standardized to detect MTB antigens and antibodies against MTB in the CSF of TBM patients.
METHODS
CSF samples were collected from 156 registered patients suffering from various neurological disorders, including 56 cases of TBM. Polyclonal antibodies to Culture Filtrate Protein (CFP), H37Rv strain, an MTB antigen, obtained from Colorado State University (USA), were used to detect MTB antigen in the CSF of TBM patients using the Dot ELISA method.
RESULTS
The methodology yielded a positive reaction to MTB antigens in 48 CSF samples (86%) obtained from all 56 cases of suspected TBM. The sensitivity achieved through the developed methodology could give reactivity with an antigen level 10ng/dl and above. Dot ELISA for MTB antigen was positive in only 5 out of 100 (5%) of the other neurological disorders, mainly pyogenic meningitis.
CONCLUSIONS
This rapid methodology for the detection of MTB antigen in CSF is very simple, sensitive, specific, and cost effective. This technique can be easily and routinely employed in the pathology laboratory to support the clinical diagnosis.
Publication
Journal: Proteins: Structure, Function and Genetics
January/18/2010
Abstract
Here, we describe our template-based protein modeling approach and its performance during the eighth community-wide experiment on the Critical Assessment of Techniques for Protein Structure Prediction (CASP8, http://predictioncenter.org/casp8). In CASP8, our modeling approach was supplemented by the newly developed distant homology detection method based on sequence profile-profile comparison. Detection of structural homologs that could be used as modeling templates was largely achieved by automated profile-based searches. However, the other two major steps in template-based modeling (TBM) (selection of the best template(s) and construction of the optimal sequence-structure alignment) to a large degree relied on the combination of automatic tools and manual input. The analysis of 64 domains categorized by CASP8 assessors as TBM domains revealed that we missed correct structural templates for only four of them. The use of multiple templates or their fragments enabled us to improve over the structure of the single best PDB template in about 1/3 of our models for TBM domains. Our results for sequence-structure alignments are mixed. Although many models have optimal or near optimal sequence mapping, a large fraction contains one or more misaligned regions. Strikingly, in spite of this, our TBM models have the best overall alignment accuracy scores. This clearly suggests that the correct mapping of protein sequence onto three-dimensional structure remains one of the big challenges in protein structure prediction.
Publication
Journal: Journal of Biological Inorganic Chemistry
March/15/2011
Abstract
Tyramine β-monooxygenase (TBM) is a member of a family of copper monooxygenases containing two noncoupled copper centers, and includes peptidylglycine monooxygenase and dopamine β-monooxygenase. In its Cu(II) form, TBM is coordinated by two to three His residues and one to two non-His O/N ligands consistent with a [Cu(M)(His)(2)(OH(2))(2)-Cu(H)(His)(3)(OH(2))] formulation. Reduction to the Cu(I) state causes a change in the X-ray absorption spectroscopy (XAS) spectrum, consistent with a change to a [Cu(M)(His)(2)S(Met)-Cu(H)(His)(3)] environment. Lowering the pH to 4.0 results in a large increase in the intensity of the Cu(I)-S extended X-ray absorption fine structure (EXAFS) component, suggesting a tighter Cu-S bond or the coordination of an additional sulfur donor. The XAS spectra of three variants, where the Cu(M) Met471 residue had been mutated to His, Cys, and Asp, were examined. Significant differences from the wild-type enzyme are evident in the spectra of the reduced mutants. Although the side chains of His, Cys, and Asp are expected to substitute for Met at the Cu(M) site, the data showed identical spectra for all three reduced variants, with no evidence for coordination of residue 471. Rather, the K-edge data suggested a modest decrease in coordination number, whereas the EXAFS indicated an average of two His residues at each Cu(I) center. These data highlight the unique role of the Met residue at the Cu(M) center, and pose interesting questions as to why replacement by the cuprophilic thiolate ligand leads to detectable activity whereas replacement by imidazole generates inactive TBM.
Publication
Journal: Neurology India
August/27/2006
Abstract
BACKGROUND
Endoscopic third Ventriculostomy (ETV) is one of the surgical options for obstructive hydrocephalus. There are varying opinions about results of ETV in infants. We are therefore presenting the results of ETV in 54 infants.
METHODS
A prospective study of 54 infants undergoing ETV in our institution in the last 2 years was carried out. There were 48 cases of congenital hydrocephalus with aqueductal stenosis, 6 of post tubercular meningitis hydrocephalus. Average follow up was 18 months.
RESULTS
There was 83.3% (45 cases) clinical success rate in our study. Infection, persistent cerebro-spinal fluid (CSF) leak and bleeding occurred in 4 (8%) cases each while blockage of stoma was observed in 8 (14.8%) patients. Majority of ETV stoma closure (6 out of total 8) occurred following infection (4) or bleeding during surgery (2). One patient (2%) had transient diabetes insipidus. Overall failure rate in our study was 16.7% (8 stoma blocks and 1 procedure abandoned). Low birth weight pre mature infants had higher failure rate (3 out of 5 infants 60%) compared to full term infants with normal birth weight (12.3%). Age did not have any impact on the success rate (P>0.05). Success rates were not significanlty different in patients with aqueductal stenosis (85.4%) and TBM (66.6%) (Fisher's exact test, P=0.3).
CONCLUSIONS
ETV was fairly safe and effective in full term normal birth weight infants while the results in low birth weight pre mature infants were poor.
Publication
Journal: PLoS ONE
August/25/2011
Abstract
BACKGROUND
Chemokine (C-C motif) ligand 2 CCL2/MCP-1 is among the key signaling molecules of innate immunity; in particular, it is involved in recruitment of mononuclear and other cells in response to infection, including tuberculosis (TB) and is essential for granuloma formation.
RESULTS
We identified a tag SNP for the CCL2/MCP-1 gene (rs4586 C/T). In order to understand whether this SNP may serve to evaluate the contribution of the CCL2 gene to the expression of TB disease, we further analysed distribution of its alleles and genotypes in 301 TB cases versus 338 non-infected controls (all BCG vaccinated) representing a high-risk pediatric population of North China. In the male TB subgroup, the C allele was identified in a higher rate (P = 0.045), and, acting dominantly, was found to be a risk factor for clinical TB (P = 0.029). Homozygous TT genotype was significantly associated with lower CSF mononuclear leukocyte (ML) counts in patients with tuberculous meningitis (TBM) (P = 0.001).
CONCLUSIONS
The present study found an association of the CCL2 tag SNP rs4586 C allele and pediatric TB disease in males, suggesting that gender may affect the susceptibility to TB even in children. The association of homozygous TT genotype with decreased CSF mononuclear leukocyte (ML) count not only suggests a clinical significance of this SNP, but indicates its potential to assist in the clinical assessment of suspected TBM, where delay is critical and diagnosis is difficult.
Publication
Journal: QJM - Monthly Journal of the Association of Physicians
September/29/1996
Abstract
We studied the spectrum of meningitis and impact of HIV infection retrospectively (8 months) and prospectively (4 months) in 284 adult patients with meningitis hospitalized in Soweto, South Africa. Tuberculous meningitis (TBM) was the most common cause of meningitis (25.4%) followed by acute bacterial meningitis (ABM; 22.5%), acute viral meningitis (14.1%) and cryptococcal meningitis (13%). The in-hospital mortality was>> 40% in TBM, ABM, cryptococcal meningitis, the neurosurgery and the parameningeal/parenchymal groups. At least 37.3% of all patients were HIV-seropositive (only 67.9% of patients were tested). In at least 27% of the study group the meningitis was an AIDS-defining illness (TBM, cryptococcal meningitis). Only 56.2% of patients with ABM had positive cultures (CSF or blood), of which Streptococcus pneumoniae was by far the most frequently found organism (35.8%). The spectrum of meningitis in HIV-affected communities in Africa can be expected to change towards a predominance of TBM and cryptococcal meningitis.
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