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Publication
Journal: Journal of Biological Chemistry
May/26/2010
Abstract
Lipomannan (LM) and lipoarabinomannan (LAM) are phosphatidylinositol-anchored glycans present in the mycobacterial cell wall. In Mycobacterium smegmatis, the mannan core of LM/LAM constitutes a linear chain of 20-25 alpha1,6-mannoses elaborated by 8-9 alpha1,2-monomannose side branches. At least two alpha1,6-mannosyltransferases mediate the linear mannose chain elongation, and one branching alpha1,2-mannosyltransferase (encoded by MSMEG_4247) transfers monomannose branches. An MSMEG_4247 deletion mutant accumulates branchless LAM and interestingly fails to accumulate LM, suggesting an unexpected role of mannose branching for LM synthesis or maintenance. To understand the roles of MSMEG_4247-mediated branching more clearly, we analyzed the MSMEG_4247 deletion mutant in detail. Our study showed that the deletion mutant restored the synthesis of wild-type LM and LAM upon the expression of MSMEG_4247 at wild-type levels. In striking contrast, overexpression of MSMEG_4247 resulted in the accumulation of dwarfed LM/LAM, although monomannose branching was restored. The dwarfed LAM carried a mannan chain less than half the length of wild-type LAM and was elaborated by an arabinan that was about 4 times smaller. Induced overexpression of an elongating alpha1,6-mannosyltransferase competed with the overexpressed branching enzyme, alleviating the dwarfing effect of the branching enzyme. In wild-type cells, LM and LAM decreased in quantity in the stationary phase, and the expression levels of branching and elongating mannosyltransferases were reduced in concert, presumably to avoid producing abnormal LM/LAM. These data suggest that the coordinated expressions of branching and elongating mannosyltransferases are critical for mannan backbone elongation.
Publication
Journal: Biological and Pharmaceutical Bulletin
February/11/2010
Abstract
Crude extract (CE) and aqueous (AqF) and ethyl acetate (EtOAcF) fractions of Guazuma ulmifolia Lam., Sterculiaceae and the corresponding AqF, EtOAcF of Stryphnodendron adstringens (Mart.) Coville, Leguminosae were tested for their antiviral activity against poliovirus 1 (P-1) and bovine herpesvirus 1 (BHV-1) in HEp-2 cultured cells. The antiviral activity was monitored by plaque assay and immunofluorescence assay (IFA) under virucidal and therapeutic protocols. The therapeutic protocol demonstrated statistically significant positive results with both plants and for both virus strains. The highest percentages of viral inhibition were found for G. ulmifolia EtOAcF which inhibited BHV-1 and P-1 replication by 100% and 99%, respectively (p<0.05, Student's t-test). For S. adstringens, AqF was the most efficient, inhibiting BHV-1 and P-1 by 97% and 93%, respectively (p<0.05). In the virucidal protocol, G. ulmifolia CE inhibited the replication of BHV-1 and P-1 by 60% and 26%, respectively (p<0.05), while, for S. adstringens, inhibition of 62% (p<0.05) was demonstrated only with EtOAcF for P-1. IFA demonstrated that the greatest reduction in fluorescent cell number occurred with G. ulmifolia, under the therapeutic protocol for both virus strains. However, AqF and EtOAcF of S. adstringens were most efficient with the virucidal protocol for P-1. In conclusion, we demonstrated that G. ulmifolia and S. adstringens inhibited BHV-1 and P-1 replication, as well as, blocked the synthesis of viral antigens in infected cell cultures.
Publication
Journal: Clinical Gastroenterology and Hepatology
August/17/2018
Abstract
OBJECTIVE
There have been few studies that compared the effects of lumen-apposing metal stents (LAMS) and double-pigtail plastic stents (DPS) in patients with peripancreatic fluid collections from pancreatitis. We aimed to compare technical and clinical success and adverse events in patients who received LAMS vs DPS for pancreatic pseudocysts and walled-off necrosis.
METHODS
We performed a retrospective study of endoscopic ultrasound-mediated drainage in 149 patients (65% male; mean age, 47 y) with pancreatic pseudocysts or walled-off necrosis (97 received LAMS and 152 received DPS), from January 2011 through September 2016 at a single center. We collected data on patient characteristics, outcomes, hospitalizations, and imaging findings. Technical success was defined as LAMS insertion or a minimum of 2 DPS. Clinical success was defined as resolution of pancreatic pseudocysts or walled-off necrosis based on imaging results. The primary outcome was resolution of peripancreatic fluid collection with reduced abdominal pain or obstructive signs or symptoms. Secondary outcomes included the identification and management of adverse events, number of additional procedures required to resolve fluid collection, and the recurrence of fluid collection.
RESULTS
Patients who received LAMS had larger peripancreatic fluid collections than patients who received DPS prior to intervention (P = .001), and underwent an average 1.7 interventions vs 1.9 interventions for patients who received DPS (P = .93). Technical success was achieved for 90 patients with LAMS (92.8%) vs 137 patients with DPS (90.1%) (odds ratio [OR] for success with DPS, 0.82; 95% CI, 0.33-2.0; P = .67). Despite larger fluid collections in the LAMS group, there was no significant difference in proportions of patients with clinical success following placement of LAMS (82 of 84 patients, 97.6%) vs DPS (118 of 122 patients, 96.7%) (OR for clinical success with DPS, 0.73; 95% CI, 0.13-4.0; P = .71). Adverse events developed in 24 patients who received LAMS (24.7%) vs 27 patients who received DPS (17.8%) (OR for an adverse event in a patient receiving a DPS, 0.82; 95% CI, 0.33-2.0; P = .67). However, patients with LAMS had a higher risk of pseudoaneurysm bleeding than patients with DPS (OR, 10.0; 95% CI, 1.19-84.6; P = .009).
CONCLUSIONS
In a retrospective study of patients undergoing drainage of pancreatic pseudocysts or walled-off necrosis, we found LAMS and DPS to have comparable rates of technical and clinical success and adverse events. Drainage of walled-off necrosis or pancreatic pseudocysts using DPS was associated with fewer bleeding events overall, including pseudoaneurysm bleeding, but bleeding risk with LAMS should be weighed against the trend of higher actionable perforation and infection rates with DPS.
Publication
Journal: Environmental Monitoring and Assessment
April/26/2012
Abstract
The concentrations of Cd, Cu, Pb, and Zn in sediments, water, and different plant organs of six aquatic vascular plant species, Ceratophyllum demersum L. Echinochloa pyramidalis (Lam.) Hitchc. & Chase; Eichhornia crassipes (Mart.) Solms-Laub; Myriophyllum spicatum L.; Phragmites australis (Cav.) Trin. ex Steud; and Typha domingensis (Pers.) Poir. ex Steud, growing naturally in the Nile system (Sohag Governorate), were investigated. The aim was to define which species and which plant organs exhibit the greatest accumulation and evaluate whether these species could be usefully employed in biomonitoring and phytoremediation programs. The recorded metals in water samples were above the standard levels of both US Environmental Protection Agency and Egyptian Environmental Affairs Agency except for Pb. The concentrations of heavy metals in water, sediments, and plants possess the same trend: Zn>> Cu>> Pb>> Cd which reflects the biomonitoring potentialities of the investigated plant species. Generally, the variation of heavy element concentrations in water and sediments in relation to site and season, as assessed by two-way repeated measured ANOVA, was significant (p < 0.05). However, insignificant variations were observed in the concentrations of Pb and Cd in sediments in relation to season and of Cu and Zn in relation to site. Results also showed that the selectivity of the heavy elements for the investigated plants varied significantly (p < 0.05) with species variation. The accumulation capability of the investigated species could be arranged according to this pattern: C. demersum>> E. crassipes>> M. spicatum>> E. pyramidalis>> T. domingensis>> P. australis. On the basis of the element concentrations, roots of all the studied species contain higher concentrations of Cu and Zn than shoots while leaves usually acquire the highest concentrations of Pb. Cd concentrations among different plant organs are comparable except in M. spicatum where the highest Cd concentrations were recorded in the leaves. Our results also demonstrated that all the studied species can accumulate more than 1,450-fold the concentration of the investigated heavy elements in water rendering them of interest for use in phytoremediation studies of polluted waters. Given the absence of systematic water quality monitoring, heavy elements in plants, rather than sediments, provide a cost-effective means for assessing heavy element accumulation in aquatic systems during plant organ lifespan.
Publication
Journal: PLoS Neglected Tropical Diseases
March/28/2017
Abstract
Histoplasma capsulatum comprises a worldwide complex of saprobiotic fungi mainly found in nitrogen/phosphate (often bird guano) enriched soils. The microconidia of Histoplasma species may be inhaled by mammalian hosts, and is followed by a rapid conversion to yeast that can persist in host tissues causing histoplasmosis, a deep pulmonary/systemic mycosis. Histoplasma capsulatum sensu lato is a complex of at least eight clades geographically distributed as follows: Australia, Netherlands, Eurasia, North American classes 1 and 2 (NAm 1 and NAm 2), Latin American groups A and B (LAm A and LAm B) and Africa. With the exception of the Eurasian cluster, those clades are considered phylogenetic species.
Increased Histoplasma sampling (n = 234) resulted in the revision of the phylogenetic distribution and population structure using 1,563 aligned nucleotides from four protein-coding regions. The LAm B clade appears to be divided into at least two highly supported clades, which are geographically restricted to either Colombia/Argentina or Brazil respectively. Moreover, a complex population genetic structure was identified within LAm A clade supporting multiple monophylogenetic species, which could be driven by rapid host or environmental adaptation (~0.5 MYA). We found two divergent clades, which include Latin American isolates (newly named as LAm A1 and LAm A2), harboring a cryptic cluster in association with bats.
At least six new phylogenetic species are proposed in the Histoplasma species complex supported by different phylogenetic and population genetics methods, comprising LAm A1, LAm A2, LAm B1, LAm B2, RJ and BAC-1 phylogenetic species. The genetic isolation of Histoplasma could be a result of differential dispersion potential of naturally infected bats and other mammals. In addition, the present study guides isolate selection for future population genomics and genome wide association studies in this important pathogen complex.
Publication
Journal: Mediators of Inflammation
August/31/2011
Abstract
The aim of our study was to determine whether some bacterial components as well as some proinflammatory cytokines can affect surface mast cell levels. By the use of flow cytometry technique, we documented that freshly isolated mature rat peritoneal mast cells do express surface TLR2 and TLR4 protein, but not CD14 molecules, and respond to stimulation with TLR2 and TLR4 ligands by cysteinyl leukotriene generation. The level of TLR2 protein is modulated by PGN and CCL5 treatment, but not by LPS, LAM, TNF, or IL-6. Surface mast cell TLR4 expression is affected by LPS, LAM, IL-6, and CCL5. Considering that TLR-mediated activation conditions not only engaged these cells in antibacterial defense and development of inflammation but also might influence allergic processes, our observations that surface TLR2 and TLR4 expression can be regulated both bacterial components and proinflammatory cytokines seem to be very intriguing and importance.
Publication
Journal: Clinical and Experimental Immunology
September/5/2001
Abstract
We have examined normal T-cells and T-cell lines with respect to expression of various somatostatin receptor subtypes (SSTR1--5) using RT-PCR and PCR. To evaluate the function of these receptors we have further studied the effects of subtype specific signalling on T-cell adhesion using somatostatin analogs specific for various receptors as probes. Human T-lymphocytes showed SSTR expression related to activation and stage of differentiation. Normal T-cells (peripheral blood, T-cell clone) and T-leukaemia cell lines expressed SSTR2, SSTR3 and SSTR4. Normal T-cells expressed SSTR1 and SSTR5 while T-leukaemia lines did not. SSTR5 was selectively expressed in activated normal T-cells. T-lymphocytes produced no somatostatin themselves. Somatostatin and somatostatin analogs specific for SSTR2 and/or SSTR3 enhanced adhesion of T-cells to fibronectin (FN), and to a certain extent, also to collagen type IV (CIV) and laminin (LAM). T-lymphocytes express multiple SSTR and somatostatin may therefore regulate lymphocyte functions via distinct receptor subtypes as shown here for adhesion to extracellular matrix components (ECM) via SSTR2 and SSTR3. SSTR expression also distinguishes normal and leukaemic T-cells. Our findings suggest that SSTR subtypes may be useful targets for therapy during inflammatory diseases and malignancies affecting lymphocytes.
Publication
Journal: BMC Plant Biology
December/8/2014
Abstract
BACKGROUND
Bean anthracnose is caused by the fungus Colletotrichum lindemuthianum (Sacc. & Magnus) Lams.- Scrib. Resistance to C. lindemuthianum in common bean (Phaseolus vulgaris L.) generally follows a qualitative mode of inheritance. The pathogen shows extensive pathogenic variation and up to 20 anthracnose resistance loci (named Co-), conferring resistance to specific races, have been described. Anthracnose resistance has generally been investigated by analyzing a limited number of isolates or races in segregating populations. In this work, we analyzed the response against eleven C. lindemuthianum races in a recombinant inbred line (RIL) common bean population derived from the cross Xana × Cornell 49242 in which a saturated linkage map was previously developed.
RESULTS
A systematic genetic analysis was carried out to dissect the complex resistance segregations observed, which included contingency analyses, subpopulations and genetic mapping. Twenty two resistance genes were identified, some with a complementary mode of action. The Cornell 49242 genotype carries a complex cluster of resistance genes at the end of linkage group (LG) Pv11 corresponding to the previously described anthracnose resistance cluster Co-2. In this position, specific resistance genes to races 3, 6, 7, 19, 38, 39, 65, 357, 449 and 453 were identified, with one of them showing a complementary mode of action. In addition, Cornell 49242 had an independent gene on LG Pv09 showing a complementary mode of action for resistance to race 453. Resistance genes in genotype Xana were located on three regions involving LGs Pv01, Pv02 and Pv04. All resistance genes identified in Xana showed a complementary mode of action, except for two controlling resistance to races 65 and 73 located on LG Pv01, in the position of the previously described anthracnose resistance cluster Co-1.
CONCLUSIONS
Results shown herein reveal a complex and specific interaction between bean and fungus genotypes leading to anthracnose resistance. Organization of specific resistance genes in clusters including resistance genes with different modes of action (dominant and complementary genes) was also confirmed. Finally, new locations for anthracnose resistance genes were identified in LG Pv09.
Publication
Journal: Journal of Neurology, Neurosurgery and Psychiatry
November/8/2015
Abstract
OBJECTIVE
First, to determine the sensitivity and specificity of six stroke recognition scores in a single cohort to improve interscore comparability. Second, to test four stroke severity scores repurposed to recognise stroke in parallel.
METHODS
Of 9154 emergency runs, 689 consecutive cases of preclinically 'suspected central nervous system disorder' admitted to the emergency room (ER) of the Heidelberg University Hospital were included in the validation cohort. Using data abstracted from the neurological ER medical reports, retrospective assessment of stroke recognition scores became possible for the Cincinnati Prehospital Stroke Scale (CPSS), Face Arm Speech Test (FAST), Los Angeles Prehospital Stroke Screen (LAPSS), Melbourne Ambulance Stroke Screen (MASS), Medic Prehospital Assessment for Code Stroke (Med PACS) and Recognition of Stroke in the Emergency Room score (ROSIER), and that of stroke severity scores became possible for the Kurashiki Prehospital Stroke Scale (KPSS), Los Angeles Motor Scale (LAMS) and shortened National Institutes of Health Stroke Scale (sNIHSS)-8/sNIHSS-5. Test characteristics were calculated using the hospital discharge diagnosis as the reference standard.
RESULTS
The CPSS and FAST had a sensitivity of 83% (95% CI 76 to 88) and 85% (78% to 90%) and a specificity of 69% (64% to 73%) and 68% (63% to 72%), respectively. The more complex LAPSS, MASS and Med PACS had a high specificity (92% to 98%) but low sensitivity (44% to 71%). In the ROSIER, sensitivity (80%, 73 to 85) and specificity (79%, 75 to 83) were similar. Test characteristics for KPSS, sNIHSS-8 and sNIHSS-5 were similar to the simple recognition scores (sensitivity 83% to 86%, specificity 60% to 69%). The LAMS offered only low sensitivity.
CONCLUSIONS
The simple CPSS and FAST scores provide good sensitivity for stroke recognition. More complex scores do not result in better diagnostic performance. Stroke severity scores can be repurposed to recognise stroke at the same time because test characteristics are comparable with pure stroke recognition scores. Particular shortcomings of the individual scores are discussed.
Publication
Journal: Pharmacognosy Magazine
July/13/2011
Abstract
OBJECTIVE
This paper investigates the total polyphenolic and flavonoid content as well as the antioxidant activity of Ziziphora clinopodioides Lam. extracts of different polarity.
METHODS
The total polyphenolic content was analysed using the Folin-Ciocalteu method. Total flavonoid content analysis was performed using the colorimetric method.
RESULTS
The total polyphenolic content of Z. clinopodioides is concentrated in parts of ethyl acetate (19.27%), chloroform (4.99%) and n-butanol extracts (3.94%) containing a small amount of the total polyphenolic content. The petroleum ether (0.23%) and ethanol extracts (1.64%) contain almost no polyphenolic content. The total flavonoid content of Z. clinopodioides is concentrated in parts of ethyl acetate (65.61%), chloroform (14.36%) and n-butanol extracts (10.76%) containing a small amount of the total polyphenolic content. The Z. clinopodioides Lam. ethyl acetate extract exhibits a good antioxidant activity.
CONCLUSIONS
Ethyl acetate extracts contain a large number of polyphenolic compounds (19.27%) and flavonoids (65.61%) owing to good antioxidant capacity.
Publication
Journal: Respiratory Medicine
March/12/2002
Abstract
Tuberous sclerosis (TSC) is an inherited disorder best known for its association with severe learning difficulties, epilepsy, behavioural problems, skin and renal pathology Lymphangioleiomyomatosis (LAM), characterized by alveolar smooth muscle proliferation and cystic destruction of parenchyma, occurs as an infrequent symptomatic pulmonary complication in TSC and as a very rare sporadic disease in those without signs of TSC. Considered a generalized and progressive cystic lung disease that is difficult to treat with a poor prognosis, it has been reported almost exclusively in women, most commonly presenting with dyspnoea and pneumothorax in those of childbearing age. We investigated the clinical features and prognosis of LAM in patients with TSC including the effects of treatment, stratified by the method of diagnosis of LAM (i.e. histological or radiological). We found histological proof of diagnosis in 10 of 21 patients with TSC and symptomatic lung disease, onset in childhood in four, three males with LAM, individuals with apparently focal disease, great variation in clinical course and no clear treatment benefit. In those with TSC, symptomatic LAM is infrequent but causes a significant morbidity and mortality It was not possible to detect predisposing factors, other than being female. Males with apparent LAM should be rigorously investigated.
Publication
Journal: Radiographics
March/20/2006
Abstract
Lymphangioleiomyomatosis (LAM) is an uncommon interstitial lung disease that exclusively affects women, usually during their reproductive years. LAM is characterized pathologically by abnormal proliferation of LAM cells in the lungs and in thoracic and retroperitoneal lymphatics. Thirty-three cases of LAM were reviewed retrospectively for clinical and radiologic findings. Twenty-eight (85%) of 33 women (aged 21-62 years; mean, 37.5 years) were symptomatic. Radiographs (n = 32) demonstrated reticular opacities in 21 (66%) patients, large lung volumes in 17 (53%), pleural effusion in 14 (44%), and pneumothorax in 13 (41%). High-resolution CT (n = 15) and conventional CT (n = 3) showed 2-5-mm bilateral thin-walled cysts in all patients and cysts that were 6-12 mm or larger in patients with severe lung involvement. CT depicted diffuse lung involvement by cysts in nine (50%) patients, relative sparing of lung apices in seven (39%), and relative sparing of lung bases in two (11%). Pleural effusion and pneumothorax were seen at CT in four (22%) and three (17%) patients, respectively. Four cases of tuberous sclerosis complex-associated LAM (TSC-LAM) (women aged 27-50 years; mean, 35.7 years) were similarly reviewed. Three (75%) were symptomatic. Radiographs (n = 4) demonstrated reticular opacities in three (75%) and large lung volumes in two (50%). All high-resolution CT (n = 3) and conventional CT (n = 1) studies showed 2-5-mm bilateral thin-walled cysts and cysts that were 6-12 mm or larger in two patients with severe lung involvement. Pleural effusion and pneumothorax were demonstrated at CT in three (75%) and two (50%) patients, respectively. LAM and TSC-LAM affect symptomatic women who often exhibit reticular opacities and large lung volumes at radiography and bilateral uniform small thin-walled cysts at CT. Large (>12 mm) cysts occur in patients with severe cystic lung involvement. Pneumothorax and pleural effusion are common associated findings.
Publication
Journal: Molecular and Cellular Biology
February/9/1992
Abstract
The lam locus of Aspergillus nidulans consists of two divergently transcribed genes, lamA and lamB, involved in the utilization of lactams such as 2-pyrrolidinone. Both genes are under the control of the positive regulatory gene amdR and are subject to carbon and nitrogen metabolite repression. The lamB gene and the region between the two genes have been sequenced, and the start points of transcription have been determined. Within the lam locus are two sequences with homology to elements, required for AmdR regulation, found in the 5' regions of the coregulated genes amdS and gatA. In vitro and in vivo assays were used to investigate the lam and gatA regulatory elements. One of the three gatA elements and one of the two lam elements were shown to bind AmdR protein in vivo and activate transcription. With a gel shift mobility assay, in vitro binding of AmdR protein to the functional gatA element was detected. Both the functional gatA and lam boxes contain within them a CAAT sequence. In vitro binding analysis indicates that a CCAAT-specific factor(s) binds at these sequences, adjacent to or overlapping the AmdR protein-binding site.
Publication
Journal: Antiviral Therapy
August/5/2007
Abstract
OBJECTIVE
Treatment of chronic delta hepatitis is long and difficult and better monitoring is needed.
METHODS
In this study, hepatitis delta virus (HDV) RNA, hepatitis B surface antigen (HBsAg) and hepatitis B virus (HBV) DNA were retrospectively quantified in 53 patients with hepatitis B e antigen (HBeAg)-negative chronic hepatitis delta. Twenty-one had received 28 courses of 3-5 MU interferon-alpha2b (IFN-alpha2b) thrice weekly for a median of 12.6 months (interquartile range [IQR]: 7.3-31.6), five had received eight courses of 100 mg lamivudine (LAM) daily for 23.6 months (IQR: 8.4-61.5) and 27 were untreated. The controls were 54 untreated, randomly selected, HBeAg-negative chronic hepatitis B patients without delta infection. Quantification of serum HDV RNA, HBsAg and HBV DNA were performed at baseline, during and at the end of treatment and end of follow up.
RESULTS
Untreated patients had significantly higher median HBsAg levels than controls (5,872 vs 3,501 IU/ml; P = 0.046), but lower median HBV DNA levels (2.933 vs 6.459 log10 copies/ml; P < 0.001). Median baseline HDV RNA (6.374 log10 copies/ml) was similar in IFN-alpha2b-treated, LAM-treated and untreated patients. At the end of treatment, IFN-alpha2b significantly suppressed in paired measurements HDV RNA (P = 0.012) and HBsAg (P = 0.043), but LAM was inefficient. In IFN-alpha2b-treated patients, HDV RNA became undetectable in five patients within a median of 30 months (IQR: 8-90), followed by a slower decrease in HBsAg.
CONCLUSIONS
In untreated chronic delta hepatitis, suppressed HBV replication is associated with significantly increased HBsAg serum levels. IFN-alpha2b significantly suppresses both HDV RNA and HBsAg, but LAM has no effect. Long-term IFN-alpha2b treatment (IQR: 1.5-5.0 years) appears necessary for undetectable serum HDV RNA and further treatment is required for HBsAg loss. Monitoring of HDV RNA and HBsAg serum levels in patients with chronic delta hepatitis provides insight during treatment.
Publication
Journal: Journal of Hepatology
June/1/2014
Abstract
OBJECTIVE
Adefovir (ADV) resistance mutations induce low-level cross-resistance to tenofovir in vitro. Our aim was to compare viral kinetics, nucleos(t)ide analog resistance mutations, and quasispecies (QS) evolution during therapy with tenofovir disoproxil fumarate (TDF) or emtricitabine + TDF (FTC/TDF) in selected patients with incomplete ADV responses.
METHODS
Patients with chronic hepatitis B and incomplete response to ADV were randomized in a double-blind trial of TDF vs. FTC/TDF. Extensive analysis of QS evolution was performed in 17 patients through 48 weeks of treatment.
RESULTS
At week 24, 48% of patients (9/17) achieved HBV DNA undetectability (<69 IU/ml) with no difference between treatment groups. ADV and/or LAM resistance mutations were detected in all 17 patients at baseline and in 5/6 analyzable patients at week 48. A total of 1224 reverse transcriptase clones were analyzed. Clonal analysis revealed no significant difference at baseline in QS complexity or diversity between treatment groups. There was a trend in both treatment groups for an increase in QS complexity at week 12, followed by a decrease in complexity and diversity by week 48. Analysis of individual patients showed no consistent selection/accumulation of specific viral resistance patterns during treatment, but at week 48, mutations at rtA181 persisted in 4 patients.
CONCLUSIONS
TDF or FTC/TDF demonstrated strong viral suppression in patients with an incomplete response to ADV and no significant selective pressure on pre-existing ADV or LAM resistant strains. TDF monotherapy and FTC/TDF combination therapy had a comparable impact on QS evolution.
Publication
Journal: Liver Transplantation
September/20/2006
Abstract
Hepatitis B immunoglobulin with lamivudine prophylaxis (LAM/HBIG) is effective in preventing Hepatitis B (HBV) recurrence posttransplant but is expensive and inconvenient. Lamivudine-resistant HBV, which has limited the usefulness of lamivudine monoprophylaxis in transplant, can now be effectively controlled with adefovir dipivoxil. We performed a cost-effectiveness analysis on the strategies of lamivudine prophylaxis with adefovir rescue(LAM/ADV) compared to combination LAM/intravenous fixed high-dose HBIG prophylaxis(LAM/ivHBIG) or LAM/intramuscular HBIG prophylaxis(LAM/imHBIG). Markov modeling was performed with analysis from societal perspective. Probability rates were derived from systematic review of the literature and cost taken from MEDICARE database. Outcome measures were incremental cost-effectiveness ratio(ICER) and cost to prevent each HBV recurrence and death. Analysis was performed at 5 years posttransplant as well as at end of life expectancy (15 years). Combination LAM/ivHBIG cost an additional USD562,000 at 15 years, while LAM/imHBIG cost an additional USD139,000 per patient compared to LAM/ADV. Although there is an estimated increase in recurrence of 53% with LAM/ADV and 7.6% increased mortality at the end of life expectancy (15 years), the ICER of LAM/ivHBIG over LAM/ADV treatment is USD760,000 per quality-adjusted life-years and for LAM/imHBIG, USD 188,000. Cost-effectiveness is most sensitive to cost of HBIG. Lamivudine prophylaxis with adefovir dipivoxil salvage offers the more cost-effective option for HBV patients undergoing liver transplant but with higher recurrence and death rate using a model that favors LAM/HBIG. Lowering the cost of HBIG maintenance will improve cost-effectiveness of LAM/HBIG strategy. In conclusion, a tailored approach based on individual risks will optimize the cost-benefit of HBV transplant prophylaxis.
Publication
Journal: Nucleic Acids Research
March/19/2015
Abstract
The La-related proteins (LARPs) form a diverse group of RNA-binding proteins characterized by the possession of a composite RNA binding unit, the La module. The La module comprises two domains, the La motif (LaM) and the RRM1, which together recognize and bind to a wide array of RNA substrates. Structural information regarding the La module is at present restricted to the prototypic La protein, which acts as an RNA chaperone binding to 3' UUUOH sequences of nascent RNA polymerase III transcripts. In contrast, LARP6 is implicated in the regulation of collagen synthesis and interacts with a specific stem-loop within the 5' UTR of the collagen mRNA. Here, we present the structure of the LaM and RRM1 of human LARP6 uncovering in both cases considerable structural variation in comparison to the equivalent domains in La and revealing an unprecedented fold for the RRM1. A mutagenic study guided by the structures revealed that RNA recognition requires synergy between the LaM and RRM1 as well as the participation of the interdomain linker, probably in realizing tandem domain configurations and dynamics required for substrate selectivity. Our study highlights a considerable complexity and plasticity in the architecture of the La module within LARPs.
Publication
Journal: BMC Evolutionary Biology
July/19/2015
Abstract
BACKGROUND
Mangrove forests are ecologically important but globally threatened intertidal plant communities. Effective mangrove conservation requires the determination of species identity, management units, and genetic structure. Here, we investigate the genetic distinctiveness and genetic structure of an iconic but yet taxonomically confusing species complex Rhizophora mucronata and R. stylosa across their distributional range, by employing a suite of 20 informative nuclear SSR markers.
RESULTS
Our results demonstrated the general genetic distinctiveness of R. mucronata and R. stylosa, and potential hybridization or introgression between them. We investigated the population genetics of each species without the putative hybrids, and found strong genetic structure between oceanic regions in both R. mucronata and R. stylosa. In R. mucronata, a strong divergence was detected between populations from the Indian Ocean region (Indian Ocean and Andaman Sea) and the Pacific Ocean region (Malacca Strait, South China Sea and Northwest Pacific Ocean). In R. stylosa, the genetic break was located more eastward, between populations from South and East China Sea and populations from the Southwest Pacific Ocean. The location of these genetic breaks coincided with the boundaries of oceanic currents, thus suggesting that oceanic circulation patterns might have acted as a cryptic barrier to gene flow.
CONCLUSIONS
Our findings have important implications on the conservation of mangroves, especially relating to replanting efforts and the definition of evolutionary significant units in Rhizophora species. We outlined the genetic structure and identified geographical areas that require further investigations for both R. mucronata and R. stylosa. These results serve as the foundation for the conservation genetics of R. mucronata and R. stylosa and highlighted the need to recognize the genetic distinctiveness of closely-related species, determine their respective genetic structure, and avoid artificially promoting hybridization in mangrove restoration programmes.
Publication
Journal: Glycobiology
June/15/2005
Abstract
Mycobacteria possess a unique, highly evolved, carbohydrate- and lipid-rich cell wall that is believed to be important for their survival in hostile environments. Until now, our understanding of mycobacterial cell wall structure has been based upon destructive isolation and fragmentation of individual cell wall components. This study describes the observation of the major cell wall structures in live, intact mycobacteria using 2D and 3D high-resolution magic-angle spinning (HR-MAS) nuclear magnetic resonance (NMR). As little as 20 mg (wet weight) of [13C]-enriched cells were required to produce a whole-cell spectra in which discrete cross-peaks corresponding to specific cell wall components could be identified. The most abundant signals of the arabinogalactan (AG) and lipoarabinomannan (LAM) were assigned in the HR-MAS NMR spectra by comparing the 2D and 3D NMR whole-cell spectra with the spectra of purified cellular components. This study confirmed that the structures of the AG and LAM moieties in the cell wall of live mycobacteria are consistent with structural reports in the literature, which were obtained via degradative analysis. Most important, by using intact cells it was possible to directly demonstrate the effects of ethambutol on the mycobacterial cell wall polysaccharides, characterize the effects of embB gene knockout in the M. smegmatis DeltaembB mutant, and observe differences in the cell wall structures of two mycobacterial species (M. bovis BCG and M. smegmatis.) Herein, we show that HR-MAS NMR is a powerful, rapid, nondestructive technique to monitor changes in the complex, carbohydrate-rich cell wall of live mycobacterial cells.
Publication
Journal: African journal of traditional, complementary, and alternative medicines : AJTCAM
May/19/2010
Abstract
Plants used in traditional medicine in Bukoba Rural district in Tanzania were evaluated for their in vitro antimicrobial activities. Plant materials from eight plant species (Harungana madagascariensis (Lam) Poir., Jatropha curcas L., Lantana trifolia L., Plectranthus barbatus Andr., Pseudospondias microcarpa Engl., Psorospermum febrifugum Spach, Teclea nobilis Del. and Vernonia adoensis [Warp.] SL) were collected based on ethnomedical information provided by traditional herbal practitioners. Results of the study indicate that extracts from the eight plant species were active against at least one or more of the test organisms (Bacillus subtilis, Staphylococcus aureus [gram positive], Escherichia coli, Pseudomonas aeruginosa [gram negative] and Candida albicans [Yeast]). A profile of secondary metabolites (alkaloids, terpenoids, triterpenes, phenolics, tannins, flavonoids, anthraquinones, flavonols/flavones and /or chalcones, sterols and saponins) was obtained for three plant species (Jatropha curcas L., Plectranthus barbatus Andr., and Pseudospondias microcarpa Engl.). The paper discusses the probable therapeutic basis of these traditional plants based on their secondary metabolite profiles and for the first time draws research attention to Bukoba Rural district as a source for plants with potential pharmaceutical applications.
Publication
Journal: Radiology
April/14/2010
Abstract
OBJECTIVE
To determine if sclerotic bone lesions evident at body computed tomography (CT) are of value as a diagnostic criterion of tuberous sclerosis complex (TSC) and in the differentiation of TSC with lymphangioleiomyomatosis (LAM) from sporadic LAM.
METHODS
Informed consent was signed by all patients in this HIPAA-compliant study approved by the institutional review board. Retrospective analysis was performed of the body CT studies of 472 patients: 365 with sporadic LAM, 82 with TSC/LAM, and 25 with TSC. The images were reviewed by using a picture archiving and communication system workstation with bone settings (window width, 1500 HU; window level, 300 HU) and fit-to-screen option. CT image characteristics assessed included shape, size, and distribution of sclerotic bone lesions with subsequent calculation of differences in the frequency of these lesions.
RESULTS
Most commonly the sclerotic bone lesions were round, measured 0.3 cm (range, 0.2-3.2), and were distributed throughout the spine. The frequencies differed among the three patient groups Four or more sclerotic bone lesions were detected in all 25 (100%) of those with TSC, with a sensitivity of .89 (72 of 82) and specificity of .97 (355 of 367) in the differentiation of sporadic LAM from TSC/LAM (P < .01).
CONCLUSIONS
The number of sclerotic bone lesions at body CT is of potential value in the diagnosis of TSC and in the differentiation of patients with sporadic LAM from those with TSC/LAM. (c) RSNA, 2010.
Publication
Journal: Journal of Agricultural and Food Chemistry
September/1/2008
Abstract
Artocarpus heterophyllus Lam is a large evergreen tree cultivated throughout Southeast Asia for its fruits. Its leaves and roots have been used for medicinal purposes. The aim of this work was to study the in vitro anti-inflammatory effects of phenolic compounds isolated from the ethyl acetate extracts of the fruits of Artocarpus heterophyllus. Three phenolic compounds were characterized as artocarpesin [5,7,2',4'-tetrahydroxy-6-(3-methylbut-3-enyl) flavone] ( 1), norartocarpetin (5,7,2',4'-tetrahydroxyflavone) ( 2), and oxyresveratrol [ trans-2,4,3',5'-tetrahydroxystilbene] ( 3) by spectroscopic methods and through comparison with data reported in the literatures. The anti-inflammatory effects of the isolated compounds ( 1- 3) were evaluated by determining their inhibitory effects on the production of proinflammatory mediators in lipopolysaccharide (LPS)-activated RAW 264.7 murine macrophage cells. These three compounds exhibited potent anti-inflammatory activity. The results indicated that artocarpesin ( 1) suppressed the LPS-induced production of nitric oxide (NO) and prostaglandin E 2 (PGE 2) through the down-regulation of inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX-2) protein expressions. Thus, artocarpesin ( 1) may provide a potential therapeutic approach for inflammation-associated disorders.
Publication
Journal: BMJ Open
December/23/2015
Abstract
OBJECTIVE
To determine if urinary lipoarabinomannan (LAM) may serve as a biomarker to monitor antituberculosis (TB) therapy response, and whether LAM results before and after treatment are predictive of patient outcomes.
METHODS
Prospective cohort.
METHODS
Outpatient referral clinic and tertiary hospital in South Africa.
METHODS
Adults (≥18 years) with ≥2 TB-related symptoms (cough, fever, weight loss, night sweats) for ≥2 weeks being initiated on anti-TB therapy.
METHODS
On enrolment, we obtained urine and nebulised sputum specimens, offered HIV testing and started participants on anti-TB therapy for ≥6 months. We collected urine samples after the 2-month intensive treatment phase and at the completion of anti-TB therapy. Positive LAM results were graded from 1 (low) to 5 (high). Participants were followed for >3 years.
METHODS
The primary outcome was change in urine LAM results during anti-TB therapy. The secondary outcome was all-cause mortality.
RESULTS
Among 90 participants, 57 (63%) had culture-confirmed pulmonary TB. Among the 88 participants tested, 82 (93%) were HIV-infected with median CD4 168/mm(3) (IQR 89-256/mm(3)). During anti-TB therapy, the percentage of LAM-positive participants decreased from baseline to 2 months (32% to 16%), and from baseline to 6-months (32% to 10%) (p values <0.005). In multivariate longitudinal analyses, urine LAM positivity and grade decreased among those with culture-confirmed pulmonary TB (p<0.0001), and had no change in sputum culture-negative participants. At the 2-month visit, participants with positive laboratory-based LAM or rapid LAM with ≥2+ grade had a significantly greater risk of mortality. In analyses adjusted for age, sex, baseline Karnofsky score and HIV status, participants with a rapid LAM ≥2+ grade after 2 months of anti-TB therapy had a 5.6-fold (95% CI 1.2 to 25.2) greater risk of mortality.
CONCLUSIONS
Rapid urine LAM testing may be a valuable tool to monitor anti-TB therapy response and to assess prognosis of patients being treated for pulmonary TB in HIV-endemic regions.
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Publication
Journal: Stem Cell Research and Therapy
May/14/2015
Abstract
BACKGROUND
Mesenchymal stem cells (MSCs) reside in a variety of tissues and provide a stromal role in regulating progenitor cell function. Current studies focus on identifying the specific factors in the niche that can alter the MSC secretome, ultimately determining the effectiveness and timing of tissue repair. The purpose of the present study was to evaluate the extent to which substrate and mechanical strain simultaneously regulate MSC quantity, gene expression, and secretome.
METHODS
MSCs (Sca-1+CD45-) isolated from murine skeletal muscle (muscle-derived MSCs, or mMSCs) via fluorescence-activated cell sorting were seeded onto laminin (LAM)- or collagen type 1 (COL)-coated membranes and exposed to a single bout of mechanical strain (10%, 1 Hz, 5 hours).
RESULTS
mMSC proliferation was not directly affected by substrate or strain; however, gene expression of growth and inflammatory factors and extracellular matrix (ECM) proteins was downregulated in mMSCs grown on COL in a manner independent of strain. Focal adhesion kinase (FAK) may be involved in substrate regulation of mMSC secretome as FAK phosphorylation was significantly elevated 24 hours post-strain in mMSCs plated on LAM but not COL (P <0.05). Conditioned media (CM) from mMSCs exposed to both LAM and strain increased myoblast quantity 5.6-fold 24 hours post-treatment compared with myoblasts treated with serum-free media (P <0.05). This response was delayed in myoblasts treated with CM from mMSCs grown on COL.
CONCLUSIONS
Here, we demonstrate that exposure to COL, the primary ECM component associated with tissue fibrosis, downregulates genes associated with growth and inflammation in mMSCs and delays the ability for mMSCs to stimulate myoblast proliferation.
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