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Publication
Journal: Nephrology Dialysis Transplantation
August/15/2016
Abstract
BACKGROUND
Mammalian target of rapamycin (mTOR) inhibitors are recommended as first-line treatment of renal angiomyolipoma associated with tuberous sclerosis complex (TSC) or sporadic lymphangioleiomyomatosis (sporadic LAM), but follow-up is limited. Longer term efficacy and tolerability data from a Phase 3, double-blind, placebo-controlled trial are presented.
METHODS
Following favorable results from the primary analysis (data cutoff 30 June 2011) of the EXIST-2 trial, patients still receiving study treatment were allowed to enter an open-label extension. Everolimus was initiated at 10 mg once daily and titrated based on tolerability. The primary outcome was angiomyolipoma response rate (≥ 50% reduction from baseline in target lesion volumes). Safety was a secondary endpoint.
RESULTS
As of the cutoff date (1 May 2013), 112 patients had received everolimus, and the response rate in 107 patients with angiomyolipoma (median duration of medication exposure of 28.9 months) was 54%. The proportion of patients achieving angiomyolipoma reductions of ≥ 30% and ≥ 50% increased over time, reaching 81.6% (62/76) and 64.5% (49/76), respectively, by Week 96. No everolimus-treated patients experienced renal bleeding. The long-term safety profile was consistent with previous reports; adverse events (AEs) were mostly Grade 1/2, and there were no new safety issues. The frequency of emerging AEs and severe AEs lessened over time.
CONCLUSIONS
Longer term everolimus treatment appeared safe and effective in patients with TSC- or sporadic LAM-associated renal angiomyolipoma not requiring surgical intervention. Continued reduction in angiomyolipoma volume was demonstrated, and there was no angiomyolipoma-related bleeding; AEs were predictable and generally manageable.
BACKGROUND
clinicaltrialsgov identifier: NCT00790400 (http://clinicaltrials.gov/ct2/show/NCT00790400).
Publication
Journal: Planta
February/28/2016
Abstract
The assimilation of ammonium into organic nitrogen catalyzed by the enzyme glutamine synthetase (GS; EC 6.3.1.2) has been suggested to be the limiting step for plant nitrogen utilization (H-M. Lam et al. 1995, Plant Cell 7: 887-898). We have developed a molecular approach to increase glutamine production in transgenic poplar by the overexpression of a conifer GS gene. A chimeric construct consisting of the cauliflower mosaic virus 35S promoter fused to pine cytosolic GS cDNA and nopaline synthetase polyadenylation region was transferred into pBin19 for transformation of a hybrid poplar clone (INRA 7171-B4, Populus tremula x P. alba) via Agrobacterium tumefaciens. Transformed poplar lines were selected by their ability to grow on selective medium containing kanamycin. The presence of the introduced gene in the poplar genome was verified by Southern blotting and polymerase chain reaction analysis. Transgene expression was detected in all selected poplar lines at the mRNA level. The detection of the corresponding polypeptide (41 kDa) and increased GS activity in the transgenics suggest that pine transcripts are correctly processed by the angiosperm translational machinery and that GS1 subunits are assembled in functional holoenzymes. Expression of the pine GS1 gene in poplar was associated with an increase in the levels of total soluble protein and an increase in chlorophyll content in leaves of transformed trees. Furthermore, the mean net growth in height of GS-overexpressing clones was significantly greater than that of non-transformed controls, ranging from a 76% increase in height at 2 months to a 21.3% increase at 6 months. Our results suggest that the efficiency of nitrogen utilization may be engineered in trees by genetic manipulation of glutamine biosynthesis.
Publication
Journal: Infection and Immunity
June/24/1998
Abstract
The macrophage mannose receptor (MR) along with complement receptors mediates phagocytosis of the M. tuberculosis virulent strains Erdman and H37Rv. We have determined that the terminal mannosyl units of the M. tuberculosis surface lipoglycan, lipoarabinomannan (LAM), from the Erdman strain serve as ligands for the MR. The biology of the MR (receptor binding and trafficking) in response to phagocytic stimuli is not well characterized. This study analyzes the MR-dependent phagocytosis mediated by Erdman LAM presented on a 1-micron-diameter phagocytic particle. Erdman LAM microspheres exhibited a time- and dose-dependent rapid increase in attachment and internalization by human monocyte-derived macrophages (MDMs). In contrast, internalization of LAM microspheres by monocytes was minimal. Microsphere internalization by MDMs was visualized and quantitated by immunofluorescence and confocal and electron microscopy and resembled conventional phagocytosis. Phagocytosis of LAM microspheres by MDMs was energy, cytoskeleton, and calcium dependent and was mannan inhibitable. Trypsin treatment of MDMs at 37 degrees C, which depleted surface and recycling intracellular pools of the MR, reduced the subsequent attachment of LAM microspheres. Trypsin treatment at 4 degrees C allowed for subsequent recovery of LAM microsphere phagocytosis at 37 degrees C by recycled MRs. Pretreatment of MDMs with cycloheximide influenced LAM microsphere phagocytosis to only a small extent, indicating that MR-dependent phagocytosis of the microspheres was occurring primarily by preformed recycled receptors. This study characterizes the requirements for macrophage phagocytosis of a LAM-coated particle mediated by the MR. This model will be useful in further characterization of the intracellular pathway taken by phagocytic particles coated with different LAM types in macrophages following ingestion.
Publication
Journal: Journal of Biological Chemistry
February/2/1998
Abstract
Lipoarabinomannan (LAM) is a putative virulence factor of Mycobacterium tuberculosis that inhibits monocyte functions, and this may involve antagonism of cell signaling pathways. The effects of LAM on protein tyrosine phosphorylation in cells of the human monocytic cell line THP-1 were examined. LAM promoted tyrosine dephosphorylation of multiple cell proteins and attenuated phorbol 12-myristate 13-acetate-induced activation of mitogen-activated protein kinase. To examine whether these effects of LAM could be related to activation of a phosphatase, fractions from LAM-treated cells were analyzed for dephosphorylation of para-nitrophenol phosphate. The data show that LAM induced increased phosphatase activity associated with the membrane fraction. The Src homology 2 containing tyrosine phosphatase 1 (SHP-1) is important for signal termination and was examined as a potential target of LAM. Exposure of cells to LAM brought about (i) an increase in tyrosine phosphorylation of SHP-1, and (ii) translocation of the phosphatase to the membrane. Phosphatase assay of SHP-1 immunoprecipitated from LAM-treated cells, using phosphorylated mitogen-activated protein kinase as substrate, indicated that LAM promoted increased activity of SHP-1 in vivo. LAM also activated SHP-1 directly in vitro. Exposure of cells to LAM also attenuated the expression of tumor necrosis factor-alpha, interleukin-12, and major histocompatibility class II molecules. These results suggest that one mechanism by which LAM deactivates monocytes involves activation of SHP-1.
Publication
Journal: Journal of Biological Chemistry
September/22/2002
Abstract
Lipomannan (LM) and lipoarabinomannan (LAM) are major glycolipids present in the mycobacterial cell wall that are able to modulate the host immune response. In this study, we have undertaken the structural determination of these important modulins in Mycobacterium chelonae, a fast growing pathogenic mycobacterial species. One-dimensional and two-dimensional NMR spectra were used to demonstrate that LM and LAM from M. chelonae, designated CheLM and CheLAM, respectively, possess structures that differ from the ones reported earlier in other mycobacterial species. Analysis by gas chromatography/mass spectrometry of the phosphatidyl-myo-inositol anchor, which is thought to play a role in the biological functions of these lipoglycans, pointed to a high degree of heterogeneity based on numerous combinations of acyl groups on the C-1 and C-2 positions of the glycerol moiety. Characterization of the mannan core of CheLM and CheLAM revealed the presence of novel alpha1,3-mannopyranosyl side chains. This motif, which reacted specifically with the lectin from Galanthus nivalis, was found to be unique among a panel of nine mycobacterial species. Then, CheLM and CheLAM were found to be devoid of both the mannooligosaccharide cap present in Mycobacterium tuberculosis and the inositol phosphate cap present in Mycobacterium smegmatis and other fast growing species. Tumor necrosis factor-alpha and interleukin-8 production were assessed from human macrophages with LAM preparations from different species. Our results suggest that the inositol phosphate capping may represent the major cytokine-inducing component of LAMs. This work not only underlines the diversity of LAM structures among various mycobacterial species but also provides new structures that could be useful to dissect the structure-function relationships of these complex molecules.
Publication
Journal: Journal of Cell Biology
August/13/1992
Abstract
Neutrophil adherence to cytokine-activated endothelial cell (EC) monolayers depends on the expression of the endothelial leukocyte adhesion molecule-1 (ELAM-1). The ligand for ELAM-1 is the sialylated Lewis-x antigen (SLe(x)) structure. The selectin LAM-1 (or LECAM-1) has been described as one of the SLe(x)-presenting glycoproteins involved in neutrophil binding to ELAM-1. Other presenter molecules have not yet been described. Our data demonstrate that the carcinoembryonic antigen (CEA)-like surface molecules on neutrophils--known as the nonspecific cross-reacting antigens (NCAs)--are involved in neutrophil adherence to monolayers of IL-1-beta-activated EC. The NCAs are recognized by CD66 (NCA-160 and NCA-90) and CD67 (NCA-95). Because NCA-95 and NCA-90 have previously been found to be phosphatidylinositol (PI)-linked, paroxysmal nocturnal hemoglobinuria (PNH) neutrophils (which lack PI-linked surface proteins) were tested as well. PNH neutrophils showed a diminished binding to activated EC. CD66 (on PNH cells still recognizing the transmembrane NCA-160 form) still inhibited the adherence of PNH cells to IL-1-beta-activated EC, but to a limited extent. Soluble CEA(-related) antigens inhibited normal neutrophil adherence as well, whereas neutrophil transmigration was unaffected. Sialidase-treatment as well as CD66 preclearing abolished the inhibitory capacity of the CEA(-related) antigens. The binding of soluble CEA antigens to IL-1-beta-pretreated EC was blocked by anti-ELAM-1. These soluble antigens, as well as the neutrophil NCA-160 and NCA-90, both recognized by CD66 antibodies, presented the SLe(x) determinant. Together, these findings indicate that the CD66 antigens (i.e., NCA-160/NCA-90) function as presenter molecules of the SLe(x) oligosaccharide structures on neutrophils that bind to ELAM-1 on EC.
Publication
Journal: Liver Transplantation
July/16/2006
Abstract
The aim of our study was to determine the outcomes of liver transplant recipients receiving either lamivudine (LAM) monotherapy or LAM combined with low-dose intramuscular (IM) hepatitis B Immunoglobulin (HBIG) therapy. We performed a retrospective review of the medical records of patients that had had liver transplantation in a single center for HBV-related liver diseases from December 1999 to June 2004. A total of 165 patients received LAM monotherapy (51 patients) or combined prophylaxis (114 patients) post-liver transplantation (LT) with a mean follow-up of 20.13 months. Hepatitis B relapsed in 21 patients of the hepatitis B surface antigen (HBsAg) carriers who received LAM monotherapy, with a 1- and 2-yr actuarial risk of 27.4% and 39.7%. Recurrence occurred in 16 patients of 114 patients receiving the combined prophylaxis, with a 1- and 2-yr recurrence rate of 13.5% and 15.2% (P = 0.024). A total of 25 cases (67.6%) with YMDD mutants were detected in all the 37 patients, 14 cases (66.7%) in the monotherapy group and 11 cases (68.8%) in the combination group. In conclusion, LAM and low-dose intramuscular HBIG treatment demonstrates a better result than LAM monotherapy, as prophylaxis against post-LT reinfection of the graft, but the safety and efficacy as a substitution for high-dose intravenous HBIG with LAM needs to be investigated further.
Publication
Journal: Clinical Gastroenterology and Hepatology
August/8/2017
Abstract
Endoscopic ultrasound-guided transmural drainage and necrosectomy have become the standard treatment for patients with pancreatic walled-off necrosis (WON). Lumen-apposing metal stents (LAMS) have shown success in the management of pancreatic fluid collections. However, there are few data on their specific roles in management of WON. We investigated the efficacy and safety of LAMS in treatment of WON.
We performed a retrospective multicenter case series of 124 patients with WON who underwent endoscopic transmural drainage by using LAMS at 17 tertiary care centers from January 2014 through May 2015. Patients underwent endoscopic ultrasound-guided cystogastrostomy or cystoenterostomy with placement of an LAMS into the WON collection. At the discretion of the endoscopist, we performed direct endoscopic necrosectomy, irrigation with hydrogen peroxide, and/or nasocystic drain placement. We performed endoscopic retrograde cholangiopancreatography with pancreatic duct stent placement when indicated. Concomitant therapies included direct endoscopic debridement (n = 78), pancreatic duct stent placement for leak (n = 19), hydrogen peroxide-assisted necrosectomy (n = 38), and nasocystic irrigation (n = 22). We collected data for a median time of 4 months (range, 1-34 months) after the LAMS placement. The primary outcomes were rates of technical success (successful placement of the LAMS), clinical success (resolution of WON, on the basis of image analysis, without need for further intervention via surgery or interventional radiology), and adverse events.
The median size of the WON was 9.5 cm (range, 4-30 cm). Eight patients had 2 LAMS placed for multiport access, all with technical success (100%). Clinical success was achieved in 107 patients (86.3%) after 3 months of follow-up. Thirteen patients required a percutaneous drain, and 3 required a surgical intervention to manage their WON. The stents remained patent in 94% of patients (117 of 124) and migrated in 5.6% of patients (7 of 124). The median number of endoscopic interventions was 2 (range, 1-9 interventions).
On the basis of a retrospective analysis of 124 patients, endoscopic therapy of WON by using LAMS is safe and effective. Creation of a large and sustained cystogastrostomy or cystoenterostomy tract is effective in the drainage and treatment of WON.
Publication
Journal: American Journal of Respiratory and Critical Care Medicine
May/30/2001
Abstract
Lymphangiomyomatosis (LAM) is a progressive and often fatal interstitial lung disease characterized by a diffuse proliferation of abnormal smooth muscle cells in the lungs. LAM is of unusual interest biologically because it affects almost exclusively young women. LAM can occur as an isolated disorder (sporadic LAM) or in association with tuberous sclerosis complex (TSC). Because only a minority of women with TSC develops symptomatic LAM, we hypothesized that a relationship might exist between the type of germline TSC1 or TSC2 gene mutation and the risk of developing LAM. We examined all 41 exons of the TSC2 gene and 21 coding exons of the TSC1 gene for mutations in a group of 14 women with both TSC and LAM using single-strand conformation polymorphism analysis. Seven mutations were found in TSC2 and one in TSC1. Of the seven patients with TSC2 mutations, two had the same in-frame exon 40 deletion and one had an exon 41 missense change. We conclude that germline mutations in the extreme carboxy-terminus of tuberin can result in LAM. Further studies will be required to determine whether mutations in exons 40 and 41 are associated with an increased incidence and/or severity of LAM in women with TSC.
Publication
Journal: Chest
May/29/2006
Abstract
OBJECTIVE
Pneumothorax is a common complication of lymphangioleiomyomatosis (LAM), and the optimal approach to its treatment and prevention is unknown. Chemical or surgical pleurodesis are often required to prevent recurrence. However, their efficacy in LAM is unclear, and whether they contribute to perioperative complications during lung transplantation is uncertain.
METHODS
The LAM Foundation database of registered patients.
METHODS
A questionnaire was sent to all registered patients who had at least one pneumothorax to determine rates and patterns of recurrence and efficacy of interventions. A second questionnaire was sent to registered LAM patients who received a lung transplant.
METHODS
Of 395 registered patients, 260 patients (66%) reported at least one pneumothorax during their lifetime, 193 of whom (74%) completed the questionnaire. Of the 85 lung transplant patients who were sent a separate questionnaire, 80 patients (94%) responded.
METHODS
None.
RESULTS
Of the 193 respondents to the pneumothorax questionnaire, data on 676 episodes of pneumothorax were collected. Eighty-two percent (158 of 193 patients) had their first pneumothorax prior to a diagnosis of LAM. One hundred forty patients (73%) had at least one additional pneumothorax, either an ipsilateral recurrence (99 of 140 patients, 71%) or a contralateral pneumothorax (104 of 140 patients, 74%). Recurrence rates were 66% after conservative therapy, 27% after chemical pleurodesis, and 32% after surgery. In patients who had undergone lung transplantation, prior chemical or surgical pleurodesis was performed in 45 of 80 patients (56%). Fourteen of 80 patients (18%) reported pleural-related postoperative bleeding, 13 of whom (93%) had prior pleurodesis.
CONCLUSIONS
Chemical pleurodesis or surgery are equally effective and better than conservative therapy in preventing recurrence of pneumothorax in LAM. Due to the high recurrence rate, either procedure should be considered for the initial pneumothorax in these patients. However, both contribute to increased perioperative bleeding following lung transplantation, with no effect on length of hospital stay.
Publication
Journal: American Journal of Respiratory Cell and Molecular Biology
June/12/2006
Abstract
The loss of TSC2 function is associated with the pathobiology of lymphangioleiomyomatosis (LAM), which is characterized by the abnormal proliferation, migration, and differentiation of smooth muscle-like cells within the lungs. Although the etiology of LAM remains unknown, clinical and genetic evidence provides support for the neoplastic nature of LAM. The goal of this study was to determine the role of tumor suppressor TSC2 in the neoplastic potential of LAM cells. We show that primary cultures of human LAM cells exhibit increased migratory activity and invasiveness, which is abolished by TSC2 re-expression. We found that TSC2 also inhibits cell migration through its N-terminus, independent of its GTPase-activating protein activity. LAM cells show increased stress fiber and focal adhesion formation, which is attenuated by TSC2 re-expression. The small GTPase RhoA is activated in LAM cells compared with normal human mesenchymal cells. Pharmacologic inhibition of Rho activity abrogates LAM cell migration; RhoA activity was also abolished by TSC2 re-expression or TSC1 knockdown with specific siRNA. These data demonstrate that TSC2 controls cell migration through its N-terminus by associating with TSC1 and regulating RhoA activity, suggesting that TSC2 may play a critical role in modulating cell migration and invasiveness, which contributes to the pathobiology of LAM.
Publication
Journal: BMC Infectious Diseases
July/23/2012
Abstract
BACKGROUND
Detection of lipoarabinomannan (LAM), a Mycobacterium tuberculosis (Mtb) cell wall antigen, is a potentially attractive diagnostic. However, the LAM-ELISA assay has demonstrated variable sensitivity in diagnosing TB in diverse clinical populations. We therefore explored pathogen and host factors potentially impacting LAM detection.
METHODS
LAM-ELISA assay testing, sputum smear and culture status, HIV status, CD4 cell count, proteinuria and TB outcomes were prospectively determined in adults diagnosed with TB and commencing TB treatment at a South African township TB clinic. Sputum TB isolates were characterised by IS61110-based restriction fragment length polymorphism (RFLP) and urines were tested for mycobacteriuria by Xpert® MTB/RIF assay.
RESULTS
32/199 (16.1%) of patients tested LAM-ELISA positive. Median optical density and proportion testing LAM positive remained unchanged during 2 weeks of treatment and then declined over 24 weeks. LAM was associated with positive sputum smear and culture status, HIV infection and low CD4 cell counts but not proteinuria, RFLP strain or TB treatment outcome. The sensitivity of LAM for TB in HIV-infected patients with CD4 counts of ≥ 200, 100-199, 50-99, and < 50 cells/μl, was 15.2%, 32%, 42.9%, and 69.2% respectively. Mycobacteriuria was found in 15/32 (46.9%) of LAM positive patients and in none of the LAM negative controls.
CONCLUSIONS
Urinary LAM was related to host immune factors, was unrelated to Mtb strain and declined steadily after an initial 2 weeks of TB treatment. The strong association of urine LAM with mycobacteriuria is a new finding, indicating frequent TB involvement of the renal tract in advanced HIV infection.
Publication
Journal: PLoS ONE
March/25/2013
Abstract
BACKGROUND
Hospitals in sub-Saharan Africa are inundated with HIV-infected patients and tuberculosis (TB) is the commonest opportunistic infection in this sub-group. Up to one third of TB-HIV co-infected patients fail to produce a sputum sample (sputum scarce) and diagnosis is thus often delayed or missed. We investigated the sensitivity of urine-based methods (Xpert MTB/RIF, LAM strip test and LAM ELISA) in such patients.
RESULTS
281 HIV-infected hospitalised patients with clinically suspected TB provided a spot urine sample. The reference standard was culture positivity for Mycobacterium tuberculosis on ≥1 sputum or extra-pulmonary sample. MTB/RIF was performed using 1 ml of both unprocessed and, when possible, concentrated urine. Each unconcentrated urine sample was also tested using the Clearview LAM ELISA and Alere LAM strip test. 42% (116/242) of patients had culture-proven TB. 18% (20/54) were sputum scarce. In sputum-scarce patients, the sensitivity of urine MTB/RIF and LAM ELISA was 40% (95%CI: 22-61) and 60% (95%CI: 39-78), respectively. Urine MTB/RIF specificity was 98% (95%CI: 95-100). Combined sensitivity of urine LAM ELISA and MTB/RIF was better than MTB/RIF alone [MTB/RIF and LAM: 70% (95%CI: 48-85) vs. MTB/RIF: 40% (95%CI: 22-61), p = 0.03]. Significant predictors of urine MTB/RIF positivity were CD4<50 cells/ml (p = 0.001), elevated protein-to-creatinine ratio (p<0.001) and LAM ELISA positivity (p<0.001). Urine centrifugation and pelleting significantly increased the sensitivity of MTB/RIF over unprocessed urine in paired samples [42% (95%CI: 26-58) vs. 8% (95%CI: 0-16), p<0.001]. Urine MTB/RIF-generated C(T) values correlated poorly with markers of bacillary burden (smear grade and time-to-positivity).
CONCLUSIONS
This preliminary study indicates that urine-based MTB/RIF, alone or in combination with LAM antigen detection, may potentially aid the diagnosis of TB in HIV-infected patients with advanced immunosuppression when sputum-based diagnosis is not possible. Concentration of urine prior to MTB/RIF-testing significantly improves sensitivity.
Publication
Journal: Annals of Surgery
October/10/2005
Abstract
OBJECTIVE
Assess outcomes following intrathoracic leaks after esophagectomy from 1970 to 2004 to evaluate the impact of evolving surgical and perioperative techniques on leak-associated mortality (LAM).
BACKGROUND
An intrathoracic leak following esophagectomy has historically been considered a catastrophic event, with mortality as high as 71%. Concerns about this complication often affect choice of surgical approach for esophagectomy.
METHODS
A retrospective review of all esophagectomies for cancer from 1970 to 2004 (n = 1223) was performed. Outcomes following intrathoracic anastomoses (n = 621) were analyzed by era: historical 1970-1986 (n = 145) and modern 1987-2004 (n = 476).
RESULTS
There was no difference in the frequency of leak between the time intervals (4.8% versus 6.3%, P = 0.5). Despite a significant increase in the use of preoperative chemoradiation (1% versus 42%, P < 0.001) in the historical versus modern era, the overall mortality decreased from 11% to 2.5% (P < 0.001). The LAM was markedly reduced from 43% to 3.3% (P = 0.016). Factors associated with LAM included failure to use enteral nutrition (HR 13.22, CI 1.8-96.8) and era in which the surgery was performed (HR 18.3, 1.9-180). Other differences included an increased proportion of successful reoperations for leak control (11/30 versus 0/7, P = 0.08) and use of reinforcing muscle flaps (7/11). In the modern era, perioperative mortality is not significantly different for patients with or without intrathoracic leaks (3.3% versus 2.5%, P = 0.55), nor is long-term survival (P = 0.16).
CONCLUSIONS
Modern surgical management of intrathoracic leaks results in no increased mortality and has no impact on long-term survival. Clinical decisions regarding the use of intrathoracic anastomoses should not be affected by concerns of increased mortality from leak.
Publication
Journal: Hepatology
May/21/2006
Abstract
Tenofovir disoproxil fumarate (TDF) has shown in vitro activity against both HIV and hepatitis B virus (HBV). We retrospectively evaluated the efficacy of TDF (300 mg/d), administered as a part of anti-retroviral therapy, in a large cohort of HIV/HBV-coinfected patients. Sixty-five HIV/HBV-coinfected patients who received TDF for at least 6 months with serum HBV DNA levels above 2.3 log10 copies/mL at TDF initiation and who had stored serum samples before and during TDF therapy were included. Serum HBV DNA was measured on stored samples. The median follow-up period was 12 (Q1-Q3: 8-17) months. Serum hepatitis B e antigen (HBeAg) was positive in 54 patients (83.1%). Fifty-two patients (80.0%) were receiving lamivudine (LAM) (150 mg twice a day), and 68.8% had documented LAM resistance at baseline. Among HBeAg-positive patients, the median reduction from baseline (8.17; Q1-Q3 = 7.30-8.30 log10 copies/mL) of serum HBV DNA was 4.56 log10 copies/mL (Q1-Q3 = 3.33-5.55) (P < .0001). In HBeAg-negative patients, serum HBV DNA decline from baseline (4.83; Q1-Q3 = 2.69-6.40 log10 copies/mL) was 2.53 log10 copies/mL (Q1-Q3 = 0.39-4.10). At the end of the study, HBV DNA became undetectable in 29.6% and 81.6% of the HBeAg-positive and HBeAg-negative patients, respectively. Serum HBeAg became negative in 4 patients, 2 of whom acquired serum hepatitis B e antibody. In conclusion, this retrospective analysis demonstrates the efficacy of TDF against wild-type, presumed precore mutants and LAM-resistant HBV when used as a part of anti-retroviral therapy in HIV-coinfected patients.
Publication
Journal: PLoS ONE
July/1/2009
Abstract
BACKGROUND
Current tools for the diagnosis of tuberculosis pleural effusions are sub-optimal. Data about the value of new diagnostic technologies are limited, particularly, in high burden settings. Preliminary case control studies have identified IFN-gamma-inducible-10 kDa protein (IP-10) as a promising diagnostic marker; however, its diagnostic utility in a day-to-day clinical setting is unclear. Detection of LAM antigen has not previously been evaluated in pleural fluid.
METHODS
We investigated the comparative diagnostic utility of established (adenosine deaminase [ADA]), more recent (standardized nucleic-acid-amplification-test [NAAT]) and newer technologies (a standardized LAM mycobacterial antigen-detection assay and IP-10 levels) for the evaluation of pleural effusions in 78 consecutively recruited South African tuberculosis suspects. All consenting participants underwent pleural biopsy unless contra-indicated or refused. The reference standard comprised culture positivity for M. tuberculosis or histology suggestive of tuberculosis.
RESULTS
Of 74 evaluable subjects 48, 7 and 19 had definite, probable and non-TB, respectively. IP-10 levels were significantly higher in TB vs non-TB participants (p<0.0001). The respective outcomes [sensitivity, specificity, PPV, NPV %] for the different diagnostic modalities were: ADA at the 30 IU/L cut-point [96; 69; 90; 85], NAAT [6; 93; 67; 28], IP-10 at the 28,170 pg/ml ROC-derived cut-point [80; 82; 91; 64], and IP-10 at the 4035 pg/ml cut-point [100; 53; 83; 100]. Thus IP-10, using the ROC-derived cut-point, missed approximately 20% of TB cases and mis-diagnosed approximately 20% of non-TB cases. By contrast, when a lower cut-point was used a negative test excluded TB. The NAAT had a poor sensitivity but high specificity. LAM antigen-detection was not diagnostically useful.
CONCLUSIONS
Although IP-10, like ADA, has sub-optimal specificity, it may be a clinically useful rule-out test for tuberculous pleural effusions. Larger multi-centric studies are now required to confirm our findings.
Publication
Journal: Journal of the American Chemical Society
November/16/2003
Abstract
Lysine 2,3-aminomutase (LAM) catalyzes the interconversion of l-lysine and l-beta-lysine, by a radical mechanism initiated by the reversible, reductive homolytic scission of the C5'-S bond in S-adenosylmethionine (SAM) to form methionine and the 5'-deoxyadenosyl radical at the active site. LAM is a member of a superfamily of enzymes in which a [4Fe-4S]+ cluster with a unique, noncysteinyl coordinated Fe provides the electron required in the cleavage of SAM. Little is known of the mechanism by which the electron is inserted into SAM, and it is not known whether all enzymes of the family employ the same mechanism. Selenium X-ray absorption spectroscopy (XAS) in the reaction of Se-adenosyl-l-selenomethionine (SeSAM) in place of SAM shows that electron transfer occurs by an inner sphere mechanism culminating in direct ligation of selenomethionine to iron upon cleavage of SeSAM. Here, we report an electron nuclear double resonance (ENDOR) spectroscopic investigation of LAM to which has been bound 14N, 17O, 2H, or 13C labeled SAM. It is found that LAM exhibits the same motif for SAM binding to the [4Fe-4S]+,2+ clusters as does pyruvate formate lyase: chelation by the unique iron of the amino and carboxylato groups of SAM; close proximity of the methionine methyl group to the cluster. However, there appear to be significant, and possibly mechanistically important, differences in the details of the binding geometry of SAM. On the basis of the correlation of the ENDOR and XAS spectroscopic results, we postulate a mechanism by which LAM cleaves SAM to generate an intermediate where N, O, and S of the methionine product are bound to the octahedrally coordinated unique Fe of the [4Fe-4S] cluster.
Publication
Journal: PLoS ONE
June/3/2012
Abstract
The acquisition of distinct cell fates is central to the development of multicellular organisms and is largely mediated by gene expression patterns specific to individual cells and tissues. A spatially and temporally resolved analysis of gene expression facilitates the elucidation of transcriptional networks linked to cellular identity and function. We present an approach that allows cell type-specific transcriptional profiling of distinct target cells, which are rare and difficult to access, with unprecedented sensitivity and resolution. We combined laser-assisted microdissection (LAM), linear amplification starting from <1 ng of total RNA, and RNA-sequencing (RNA-Seq). As a model we used the central cell of the Arabidopsis thaliana female gametophyte, one of the female gametes harbored in the reproductive organs of the flower. We estimated the number of expressed genes to be more than twice the number reported previously in a study using LAM and ATH1 microarrays, and identified several classes of genes that were systematically underrepresented in the transcriptome measured with the ATH1 microarray. Among them are many genes that are likely to be important for developmental processes and specific cellular functions. In addition, we identified several intergenic regions, which are likely to be transcribed, and describe a considerable fraction of reads mapping to introns and regions flanking annotated loci, which may represent alternative transcript isoforms. Finally, we performed a de novo assembly of the transcriptome and show that the method is suitable for studying individual cell types of organisms lacking reference sequence information, demonstrating that this approach can be applied to most eukaryotic organisms.
Publication
Journal: Journal of Ethnopharmacology
December/21/2006
Abstract
In India, drumstick (Moringa oleifera Lam. (Moringaceae)) is commonly used as a phytotherapeutic agent. The effect of oral administration of aqueous and alcoholic extract of Moringa oleifera root-wood on calcium oxalate urolithiasis has been studied in male Wistar albino rats. Ethylene glycol feeding resulted in hyperoxaluria as well as increased renal excretion of calcium and phosphate. Supplementation with aqueous and alcoholic extract of Moringa oleifera root-wood significantly reduced the elevated urinary oxalate, showing a regulatory action on endogenous oxalate synthesis. The increased deposition of stone forming constituents in the kidneys of calculogenic rats was also significantly lowered by curative and preventive treatment using aqueous and alcoholic extracts. The results indicate that the root-wood of Moringa oleifera is endowed with antiurolithiatic activity.
Publication
Journal: BMC Infectious Diseases
June/22/2014
Abstract
Detection of the Mycobacterium tuberculosis cell wall antigen lipoarabinomannan (LAM) in urine permits diagnoses of tuberculosis (TB) to be made in HIV-infected patients with advanced immunodeficiency. This can be achieved at the point-of-care within just 30 minutes using the Determine TB-LAM, which is a commercially available, lateral-flow urine 'strip test' assay. The assay has been shown to have useful diagnostic accuracy in patients enrolling in antiretroviral treatment services or in HIV-infected patients requiring admission to hospital medical wards in sub-Saharan Africa. Such patients have high mortality risk and have most to gain from rapid diagnosis of TB and immediate initiation of treatment. However, few studies using this assay have yet been reported and many questions remain concerning the correct use of the assay, interpretation of results, the role of the assay as an add-on test within existing diagnostic algorithms and the types of further studies needed. In this paper we address a series of questions with the aim of informing the design, conduct and interpretation of future studies. Specifically, we clarify which clinical populations are most likely to derive benefit from use of this assay and how patients enrolled in such studies might best be characterised. We describe the importance of employing a rigorous microbiological diagnostic reference standard in studies of diagnostic accuracy and discuss issues surrounding the specificity of the assay in different geographical areas and potential cross-reactivity with non-tuberculous mycobacteria and other organisms. We highlight the importance of careful procedures for urine collection and storage and the critical issue of how to read and interpret the test strips. Finally, we consider how the assay could be used in combination with other assays and outline the types of studies that are required to build the evidence base concerning its use.
Publication
Journal: Journal of Clinical Microbiology
November/3/2010
Abstract
Urinary lipoarabinomannan (LAM) detection is a promising approach for rapid diagnosis of active tuberculosis (TB). In microbiologically confirmed TB patients, quantitative LAM detection results increased progressively with bacillary burden and immunosuppression. Patients with disseminated TB and/or advanced HIV are target populations for whom urine LAM detection may be particularly useful.
Publication
Journal: Cellular Signalling
February/19/2004
Abstract
Tumour suppressors hamartin and tuberin, encoded by tuberous sclerosis complex 1(TSC1) and TSC2 genes, respectively, are critical regulators of cell growth and proliferation. Mutations in TSC1 and TSC2 genes are the cause of an autosomal dominant disorder known as tuberous sclerosis complex (TSC). Another genetic disorder, lymphangioleiomyomatosis (LAM), is also associated with mutations in the TSC2 gene. Hamartin and tuberin control cell growth by negatively regulating S6 kinase 1 (S6K1) and eukaryotic initiation factor 4E binding protein 1 (4E-BP1), potentially through their upstream modulator mammalian target of rapamycin (mTOR). Growth factors and insulin promote Akt/PKB-dependent phosphorylation of tuberin, which in turn, releases S6K1 from negative regulation by tuberin and results in the activation of S6K1. Although much has been written regarding the molecular genetics of TSC and LAM, which is associated with either the loss of or mutation in the TSC1 and TSC2 genes, few reviews have addressed the intracellular signalling pathways regulated by hamartin and tuberin. The current review will fill the gap in our understanding of their role in cellular signalling networks, and by improving this understanding, an integrated picture regarding the normal function of tuberin and hamartin is beginning to emerge.
Publication
Journal: Journal of Immunology
January/23/1992
Abstract
Several structural homologues of the chemotactic peptide neutrophil-activating peptide 1/IL-8 (NAP-1/IL-8) were tested for their ability to influence the expression and function of adhesion-promoting receptors on human polymorphonuclear leukocytes (PMN). NAP-2, melanoma growth stimulatory activity, and two forms of NAP-1/IL-8 (ser-NAP-1/IL-8 and ala-NAP-1/IL-8, consisting of 72 and 77 amino acids, respectively), each caused an increase in the expression of CD11b/CD18 (CR3) and CR1, which was accompanied by a decrease in the expression of leukocyte adhesion molecule-1 (LAM-1, LECAM-1). The binding activity of CD11b/CD18 was also enhanced 3- to 10-fold by these peptides, but enhanced function was transient: binding of erythrocytes coated with C3bi reached a maximum by 30 min and declined thereafter. Ser-NAP-1/IL-8, ala-NAP-1/IL-8, NAP-2, and melanoma growth stimulatory activity also caused a two- to threefold enhancement of the phagocytosis of IgG-coated erythrocytes (EIgG) by PMN without causing a large increase in the expression of Fc gamma receptors. Enhanced phagocytosis of EIgG appeared to be mediated through CD11b/CD18, because F(ab')2 fragments of an antibody directed against CD18 inhibited NAP-1/IL-8-stimulated ingestion of EIgG. The four active peptides caused a rapid, transient increase in the amount of F-actin within PMN, indicating that they are capable of influencing the structure of the microfilamentous cytoskeleton, which participates in phagocytosis. Two other NAP-1/IL-8-related peptides, platelet factor 4 and connective tissue-activating peptide III, were without effect on expression of CD11b/CD18, CR1, and LAM-1, binding activity of CD11b/CD18, or Fc-mediated phagocytosis, and increased actin polymerization only slightly. Our observations indicate that several members of the NAP-1/IL-8 family of peptides were capable of promoting integrin-mediated adhesion and Fc-mediated phagocytosis, processes important in the recruitment of PMN to sites of inflammation and antimicrobial responses of PMN.
Publication
Journal: Psycho-Oncology
August/28/2012
Abstract
OBJECTIVE
To explore how initial trajectories of distress experienced during the first year following diagnosis with early-stage breast cancer (ESBC) relate to subsequent long-term(6 years) psychosocial outcomes.
METHODS
285/303 Chinese women recruited 1-week post-surgery for predominantly ESBC were assessed for distress with the Chinese Health Questionnaire at 1, 4, and 8 months later.Latent growth mixture modeling revealed four distinct distress trajectories during the first 8 months following surgery (Lam et al., 2010). Six years later we reassessed 186 of these 285 women, comparing scores on the Hospital Anxiety and Depression Scale, Impact of Events Scale, and Chinese Social Adjustment Scale by first 8 months’ distress trajectory.
RESULTS
Distress trajectories over the first 8 months post-operatively predicted psychosocial outcomes 6 years later. Women with stable low levels of distress over the first 8 months postoperatively(resilient group) had the best 6-year psychosocial outcomes. Women who experienced chronic distress had significantly greater longer-term psychological distress, cancer-related distress, and poorer social adjustment in comparison to women in the resilient group. Women in the recovered or delayed-recovery groups were comparable to those in the resilient group, except for concerns about appearance and sexuality, and self-image.
CONCLUSIONS
Women with an illness trajectory characterized by chronic distress over the first 8 months post-operatively had poorest longer-term psychosocial outcomes. Clarification of determinants of chronic distress and means for early identification of at-risk women are needed.This will enable targeted optimization of interventions to prevent and manage chronic distress,improving ESBC rehabilitation efficiency.
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