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Publication
Journal: Thrombosis and Haemostasis
December/10/2000
Abstract
A monoclonal antibody (mAb 2/215) against human beta-factor XIIa (beta-FXIIa), was shown by equilibrium binding studies to have a high affinity for alpha-factor XIIa (alpha-FXIIa) (Kd 1.8 nM) and beta-FXIIa (Kd 0.65 nM) but no detectable reaction with FXII zymogen or alpha-FXIIa:C1 esterase inhibitor (C1-INH) complex. Surface plasmon resonance studies showed that the mAb 2/215 bound to immobilized alpha-FXIIa with high affinity (KD 3.93 +/- 1.46 x 10(-11) M). Western blots employing mAb 2/215 indicated that human plasma contained small amounts of alpha-FXIIa but no beta-FXIIa. mAb 2/215 did not inhibit the amidolytic activity of beta-FXIIa and protected beta-FXIIa from inhibition by C1-INH. The recovery by ELISA,employing mAb 2/215 as the capture antibody, of alpha-FXIIa added to plasma was 11.3%, 42% after inhibition of alpha-FXIIa with 3:4dichloroisocoumarin, and 82% when 0.5% Triton-X100 was added to the assay. Gel filtration showed that the majority of plasma alpha-FXIIa existed as a complex (Mr approximately 170,000). This distinctive mAb increases the capacity to study the contact system in health and disease.
Publication
Journal: Clinical Rheumatology
January/13/2008
Abstract
In this study, we investigated the safety and toxicity of isoniazid (INH) intervention therapy to the patients with latent tuberculosis who were given tumor necrosis factor alpha (TNFalpha) for the treatment of their rheumatologic diseases. In this prospective clinical study, we enrolled 86 patients receiving anti-TNFalpha therapy for their rheumatologic diseases between April 2005 and September 2006. Of all the subjects, 45 had rheumatoid arthritis, 36 had ankylosing spondylitis, and 5 had psoriatic arthritis. In addition to anti-TNFalpha therapy, 60 of the 86 patients were given INH intervention for revealed latent tuberculosis. INH at a dosage of 300 mg daily was given for 9 months. Hepatotoxicity due to the INH therapy was considered when the serum alanine aminotransferase (ALT) and/or aspartate aminotransaminase (AST) levels showed at least threefold increase with respect to their baseline serum levels. Serum ALT and AST levels were measured by enzymatic colorimetric method in fasting peripheral blood samples at 0 (baseline), 1, 2, 3, 6, and 9 months. Of 86 patients, 47 (54.7%) were women (mean age+/-SD, 44.1 +/- 10.9 years) and 39 (45.3%) were men (38.8 +/- 10.1 years). Except five patients (8.3%), liver toxicity due to the INH therapy was not encountered among the patients, and after temporarily discontinuing the INH therapy of these five subjects, serum transaminase levels returned to the normal ranges. No hepatotoxicity was observed in the non-INH group. However, there was no statistical significance between INH-treated and non-INH-treated group (p = 0.317). In addition, none of the 86 patients developed active tuberculosis infection during the treatment period. In conclusion, for those patients who were assigned to the TNFalpha treatment for their rheumatologic disorders and carrying risk for latent tuberculosis, INH intervention therapy was found to be safe and efficacious.
Publication
Journal: Journal of Biological Chemistry
August/19/2009
Abstract
KatG (catalase-peroxidase) in Mycobacterium tuberculosis is responsible for activation of isoniazid (INH), a pro-drug used to treat tuberculosis infections. Resistance to INH is a global health problem most often associated with mutations in the katG gene. The origin of INH resistance caused by the KatG[S315G] mutant enzyme is examined here. Overexpressed KatG[S315G] was characterized by optical, EPR, and resonance Raman spectroscopy and by studies of the INH activation mechanism in vitro. Catalase activity and peroxidase activity with artificial substrates were moderately reduced (50 and 35%, respectively), whereas the rates of formation of oxyferryl heme:porphyrin pi-cation radical and the decay of heme intermediates were approximately 2-fold faster in KatG[S315G] compared with WT enzyme. The INH binding affinity for the resting enzyme was unchanged, whereas INH activation, measured by the rate of formation of an acyl-nicotinamide adenine dinucleotide adduct considered to be a bactericidal molecule, was reduced by 30% compared with WT KatG. INH resistance is suggested to arise from a redirection of catalytic intermediates into nonproductive reactions that interfere with oxidation of INH. In the resting mutant enzyme, a rapid evolution of 5-c heme to 6-c species occurred in contrast with the behavior of WT KatG and KatG[S315T] and consistent with greater flexibility at the heme edge in the absence of the hydroxyl of residue 315. Insights into the effects of mutations at residue 315 on enzyme structure, peroxidation kinetics, and specific interactions with INH are presented.
Publication
Journal: Journal of Pharmacology and Experimental Therapeutics
October/18/2007
Abstract
The cystic fibrosis transmembrane conductance regulator (CFTR) represents the main Cl(-) channel in the apical membrane of epithelial cells for cAMP-dependent Cl(-) secretion. Here we report on the synthesis and screening of a small library of nontoxic alpha-aminoazaheterocycle-methylglyoxal adducts, inhibitors of wild-type (WT) CFTR and G551D-, G1349D-, and F508del-CFTR Cl(-) channels. In whole-cell patch-clamp experiments of Chinese hamster ovary (CHO) cells expressing WT-CFTR, we recorded rapid and reversible inhibition of forskolin-activated CFTR currents in the presence of the adducts 5a and 8a,b at 10 pM concentrations. Using iodide efflux experiments, we compared concentration-dependent inhibition of CFTR with glibenclamide (IC(50) = 14.7 microM), 3-[(3-trifluoromethyl)phenyl]-5-[(4-carboxyphenyl-)methylene]-2-thioxo-4-thiazolidinone (CFTR(inh)-172) (IC(50) = 1.2 microM), and alpha-aminoazaheterocycle-methylglyoxal adducts and identified compounds 5a (IC(50) = 71 pM), 8a,b (IC(50) = 2.5 nM), and 7a,b (IC(50) = 3.4 nM) as the most potent inhibitors of WT-CFTR channels. Similar ranges of inhibition were also found when these compounds were evaluated on CFTR channels with the cystic fibrosis mutations F508del (in temperature-corrected human airway epithelial F508del/F508del CF15 cells)-, G551D-, and G1349D-CFTR (expressed in CHO and COS-7 cells). No effect of compound 5a was detected on the volume-regulated or calcium-regulated iodide efflux. Picomolar inhibition of WT-CFTR with adduct 5a was also found using a 6-methoxy-N-(3-sulfopropyl)-quinolinium fluorescent probe applied to the human tracheobronchial epithelial cell line 16HBE14o-. Finally, we found comparable inhibition by 5a or by CFTR(inh)-172 of forskolin-dependent short-circuit currents in mouse colon. To the best of our knowledge, these new nontoxic alpha-aminoazaheterocycle-methylglyoxal adducts represent the most potent compounds reported to inhibit CFTR chloride channels.
Publication
Journal: Gynecologic Oncology
May/19/2004
Abstract
OBJECTIVE
Determination of the frequency and tissue distribution of inhibin-alpha (INH-alpha) in normal, hyperplastic and malignant endometrium.
METHODS
Endometrial tissue was obtained from normal, hyperplastic (glandular-cystic hyperplasia), adenomatous hyperplasia (AH grade I to III) and endometroid adenocarcinoma and immunohistochemically characterized with INH-alpha antibody.
RESULTS
INH-alpha was expressed in normal, hyperplastic and malignant endometrium. Highest expression was observed during secretory phase and glandular-cystic hyperplasia compared to all groups. A continuous decline was noted from AH grade I to III with a significance between AH I and II.
CONCLUSIONS
A menstrual cycle associated expression of INH-alpha in glandular endometrial epithelium was observed. Since AH grade II and III can be considered as a precursor of endometrial cancer, INH-alpha could be a marker of cell transformation and an endometrial tumor-suppressor agent.
Publication
Journal: Biochemical and Biophysical Research Communications
June/1/1992
Abstract
TGF beta 1 is the prototype of a superfamily of differentiation factors with at least 18 distinct members. This classification is based on amino acid homology in the C-terminus of these polypeptides. The rates of amino acid substitution for several family members were estimated from a comparison of homologous sequences derived from different species. These rates were approximately constant for any given protein, but values varied greatly between different groups. This variation is a reflection of the great functional diversity found within the TGF beta superfamily. Maximum parsimony analysis allowed us to classify members of the TGF beta superfamily into five main groups (INH alpha, MIS, TGF beta s, INH beta s and BMPs) and various subgroups. This classification predicts possible phylogenetic relationships among these proteins. In the future, it is hoped that this method of classification will be adopted by all our colleagues, as an aid in deciding whether newly discovered proteins are the product of duplicated or homologous genes. This would suggest proteins with either similar or identical functions.
Authors
Publication
Journal: Journal of Neurochemistry
September/21/1981
Abstract
When gamma-aminobutyric acid aminotransferase (GABA-T) activity was measured in vitro in rat brain, neither isoniazid (INH) nor for of its known metabolites (isonicotinic acid, acetylisoniazid, acetylhydrazine, diacetylhydrazine) inhibited the enzyme in concentrations (5 mM) far higher than those likely to be achieved when INH is administered to man. In contrast, hydrazine (5 micrometers) caused a 50% inhibition of GABA-T without inhibiting glutamic acid decarboxylase (GAD). Rats were injected daily for 109 days with hydrazine (0.08 or 0.16 mmol/kg/day), after which amino acid contents and enzyme activities were measured in their brains. Both hydrazine doses caused significant elevations of whole brain GABA content and reductions of GABA-T activity, but did not affect GAD activity. Chronic administration of hydrazine at these doses did not reduce weight gain or alter rat behavior, nor did it produce any irreversible pathologic changes in liver or alterations in hepatic aryl hydrocarbon hydroxylase activity. However, hydrazine treatment caused changes in the contents of many brain amino acids besides GABA, and markedly increased concentrations of ornithine, tyrosine, and alpha-aminoadipic acid in rat plasma. Inhibition of GABA-T activity and the other biochemical alterations observed in patients given high doses of INH probably result from hydrazine formed in the metabolic degradation of INH. Thus administration of hydrazine might be a more direct means of elevating brain GABA content in patients where this seems indicated, and might not entail a greater risk of adverse effects.
Publication
Journal: Blood
March/16/1981
Abstract
Hageman factor (HF, factor XII) that has been exposed to Sephadex-ellagic acid gels is a single-chain species (HFea) with amidolytic properties for the synthetic substrate H-D-phenylalanyl-L-pipecolyl-L-arginine p-nitroanilide. Earlier we reported that amidolysis was suppressed by incubation of HFea with specific antiserum. The present study provides additional evidence that the amidolytic properties of preparations of HFea are ascribable to this substance through an examination of a number of protease inhibitors. HFea's amidolytic properties were inhibited by alpha 2-plasmin inhibitor, antithrombin III in the presence of heparin, and Cl esterase inhibitor (Cl-INH). Additionally, it was inhibited by popcorn inhibitor, leupeptin, hexadimethrine bromide, protamine sulfate, dansyl-arginine N-(3-ethyl-1,5-pentanediyl) amide (DAPA), diisopropylphosphofluoridate (DFP), aprotinin, and at excessively high concentrations, soybean and lima bean trypsin inhibitors. The spectrum of action of agents that did or did not inhibit HFea supports the view that amidolysis by preparations of HFea is attributable to this enzyme. In general, the enzymatically active carboxy-terminal fragment of HF (HFf) was inhibited by the same agents that inhibited HFea, but aprotinin, protamine sulfate and hexadimethrine bromide were more effective against HFf than HFea, while the reverse was true of lima bean trypsin inhibitor.
Publication
Journal: Archives of Pathology and Laboratory Medicine
July/29/2002
Abstract
BACKGROUND
C1 inhibitor (C1-INH) is an alphaalpha-granules of normal human platelets also contain C1-INH, which is expressed on the platelet surface during platelet secretion in healthy patients, but it is clearly reduced in patients with hereditary angioedema (HAE).
OBJECTIVE
To evaluate the effects of in vivo C1-INH concentrate infusion on platelet responsiveness and coagulation system activity in patients with HAE.
METHODS
Assessment of the platelet activity and plasma levels of C1-INH, activated factor XII (XIIa), and prothrombin fragment F1.2 (F1.2) before and after infusion of 15 U/kg of C1-INH concentrate.
METHODS
In 6 patients (4 men and 2 women), HAE was diagnosed according to the accepted clinical and laboratory criteria.
METHODS
Platelet aggregation (final concentrations: adenosine diphosphate, 0.5, 1.25, and 2.5 microM; collagen, 5 microg/mL), C1-INH antigen (radial immunodiffusion), C1-INH activity (chromogenic substrates), and XIIa and F1.2 (enzyme-linked immunosorbent assay).
RESULTS
After C1-INH infusion, we observed a prompt increase of C1-INH level and a slow return toward its plasma preinfusion values within 4 to 7 days, a significant decrease of both adenosine diphosphate- and collagen-induced platelet aggregation versus preinfusion values (maximum after 1-2 days; P <.001), and a rapid decrease of high basal values of XIIa and F1.2 in 30 and 120 minutes, respectively.
CONCLUSIONS
These data show a role of C1-INH in the control of platelet activity and that its deficiency increases platelet aggregability and plasma levels of XIIa and F1.2 in patients with HAE.
Publication
Journal: Blood Coagulation and Fibrinolysis
May/9/1994
Abstract
Gut mucosal hypoperfusion is associated with a poor outcome following major surgery but the pathogenetic mechanisms remain poorly understood. We have examined the relationship between gut mucosal hypoperfusion, endotoxin core antibodies (EndoCAb), neutrophil elastase alpha-1 antitrypsin complexes (NE) and components of the contact system during elective major surgery. Of the 26 patients studied 16 developed gut mucosal hypoperfusion (pHi < 7.32) by the end of surgery; of these four developed multiple organ failure (MOF) and three subsequently died. In this group there was a significant rise in NE (P < 0.005) and significant reductions in components of the contact system (factor XII, antithrombin III, prekallikrein and C1-inhibitor; P < 0.001) from immediately before surgery to 24 h later. Ten patients maintained gut mucosal perfusion (pHi>> or = 7.32); none of these developed life threatening complications. In this group there was no significant increase in NE and, although there were significant reductions in some components of the contact system (P < 0.01), levels of C1-INH were not reduced. All patients demonstrated a significant reduction in both IgG and IgM EndoCAbs (P < or = 0.005) indicating exposure to endotoxin. However, the group that maintained gut mucosal perfusion had significantly higher IgG EndoCAb levels at baseline and 24 h (P < or = 0.005). These data suggest that all patients were exposed to endotoxin and that high levels of anti-endotoxin antibodies may contribute to the prevention of endotoxin-induced contact activation, neutrophil degranulation and gut mucosal hypoperfusion occurring during major surgery and thus reduce the likelihood of the development of post-operative MOF.
Publication
Journal: Systems and synthetic biology
August/22/2012
Abstract
Complex biological systems exhibit a property of robustness at all levels of organization. Through different mechanisms, the system tries to sustain stress such as due to starvation or drug exposure. To explore whether reconfiguration of the metabolic networks is used as a means to achieve robustness, we have studied possible metabolic adjustments in Mtb upon exposure to isoniazid (INH), a front-line clinical drug. The redundancy in the genome of M. tuberculosis (Mtb) makes it an attractive system to explore if alternate routes of metabolism exist in the bacterium. While the mechanism of action of INH is well studied, its effect on the overall metabolism is not well characterized. Using flux balance analysis, inhibiting the fluxes flowing through the reactions catalyzed by Rv1484, the target of INH, significantly changes the overall flux profiles. At the pathway level, activation or inactivation of certain pathways distant from the target pathway, are seen. Metabolites such as NADPH are shown to reduce drastically, while fatty acids tend to accumulate. The overall biomass also decreases with increasing inhibition levels. Inhibition studies, pathway level clustering and comparison of the flux profiles with the gene expression data indicate the activation of folate metabolism, ubiquinone metabolism, and metabolism of certain amino acids. This analysis provides insights useful for target identification and designing strategies for combination therapy. Insights gained about the role of individual components of a system and their interactions will also provide a basis for reconstruction of whole systems through synthetic biology approaches.
BACKGROUND
The online version of this article (doi:10.1007/s11693-011-9075-6) contains supplementary material, which is available to authorized users.
Publication
Journal: Molecular and Cellular Endocrinology
August/19/1999
Abstract
We have produced a transgenic (TG) mouse model expressing the Simian Virus 40 T-antigen (Tag) gene, driven by a 6-kb fragment of the mouse inhibin-alpha subunit promoter (inh-alpha). The mice develop gonadal tumors with 100% penetrance by the age of 5-8 months, of granulosa cell origin in the ovary, and of Leydig cell origin in the testis. In the present study, we characterized the hormonal regulation of proliferation of two immortalized cell lines, BLT-1, originating from a Leydig cell tumor, and NT-1, originating from a granulosa cell tumor. [3H]-thymidine incorporation in both types of cells was stimulated by activin >> or = 10-30 microg/l), while inhibin had no effect. Transforming growth factor (TGF)-beta, at>> or = 0.01 microg/l, stimulated proliferation of the granulosa tumor cells, but no effect was found on the Leydig tumor cells. Progesterone inhibited the proliferation of both cell lines, although the granulosa tumor cells were clearly less sensitive than the Leydig cells to this effect (>> or = 3 micromol/l vs.>> 10 nmol/l, respectively). hCG had no effect on the Leydig tumor cell DNA synthesis whereas at high concentration (100 microg/l) it stimulated that of the granulosa cells. We also investigated in BLT-1 and NT-1 cells whether the proliferative changes were related to concomitant changes in Tag expression. In BLT-1 cells, this was stimulated by activin, progesterone and hCG, even though the latter substance did not affect cell proliferation. In contrast, TGF-beta inhibited Tag expression. In NT-1 cells, the expression of Tag was stimulated by activin, while hCG had no effect. In contrast, it was reduced by progesterone, inhibin and TGF-beta. In conclusion, our results indicate that the granulosa and Leydig tumor cells, despite similar mechanism of immortalization, respond differently to several mitotic stimuli. The responses in the level of Tag expression in these cells did not always correlate with the changes observed in cell proliferation, indicating the independence of these two phenomena.
Publication
Journal: Experimental Parasitology
April/12/2004
Abstract
We studied the transmission-blocking effect of isonicotinic acid hydrazide (INH), a widely used anti-tuberculosis drug, against Plasmodium gallinaceum and Plasmodium berghei. INH-treatment of infected animals did not inhibit parasite development in the blood of the vertebrate host, but did inhibit exflagellation, ookinete formation, and oocyst development in the mosquito. Oocyst development was inhibited in a dose-dependent manner. The ED(50) in the P. gallinaceum/chicken/Aedes aegypti model and P. berghei/mouse/Anopheles stephensi model was 72 and 109 mg/kg, respectively. In marked contrast, in vitro exflagellation and ookinete development were not directly affected by physiological concentrations of INH. We suggest that INH exerts its inhibitory effects on the mosquito stages of the malaria parasite by an indirect, and at present undefined mechanism. Further elucidation of the mechanism how INH inhibits parasite development specifically on mosquito stages may allow us to identify new targets for malaria control strategy.
Publication
Journal: European Journal of Medicinal Chemistry
September/12/2017
Abstract
Tuberculosis (TB), which has been a scourge of humanity for thousands of years, is a worldwide pandemic disease caused mainly by Mycobacterium tuberculosis (MTB). The emergence of drug-resistant TB (DR-TB), multidrug-resistant TB (MDR-TB), extensively drug-resistant TB (XDR-TB) and totally drug-resistant TB (TDR-TB) increase the challenges to eliminate TB worldwide. Isoniazid (INH), a critical frontline anti-TB drug, is one of the most effective drugs used to treatment of TB infection for more than 60 years. Unfortunately, bacterial strains resistant to INH are becoming common which mainly due to the long-term widely use even abuse. Therefore, there is an urgent need to develop novel anti-TB agents. Numerous efforts have been undertaken to develop new anti-TB agents, but no new drug has been introduced for more than 5 decades. It has been suggested that the incorporation of lipophilic moieties into the framework of INH can increase permeation of the drug into bacterial cells, thereby enhancing the anti-TB. Therefore, INH derivatives with greater lipophilicity are emerging as one of the most potential anti-TB agents. Indeed, the INH derivative LL-3858 is in initial stages of phase II clinical trial for the treatment of TB and may be approved to treat TB in the near future. This review aims to summarize the recent advances made towards the discovery anti-TB agents holding INH as a nucleus including INH hybrids and INH hydrazide-hydrazone derivatives.
Publication
Journal: American Journal of Pathology
June/12/2008
Abstract
Cystic fibrosis is a lethal inherited disorder caused by mutations in a single gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR) protein, resulting in progressive oxidative lung damage. In this study, we evaluated the role of CFTR in the control of ubiquitin-proteasome activity and nuclear factor (NF)-kappaB/IkappaB-alpha signaling after lung oxidative stress. After a 64-hour exposure to hyperoxia-mediated oxidative stress, CFTR-deficient (cftr(-/-)) mice exhibited significantly elevated lung proteasomal activity compared with wild-type (cftr(+/+)) animals. This was accompanied by reduced lung caspase-3 activity and defective degradation of NF-kappaB inhibitor IkappaB-alpha. In vitro, human CFTR-deficient lung cells exposed to oxidative stress exhibited increased proteasomal activity and decreased NF-kappaB-dependent transcriptional activity compared with CFTR-sufficient lung cells. Inhibition of the CFTR Cl(-) channel by CFTR(inh-172) in the normal bronchial immortalized cell line 16HBE14o- increased proteasomal degradation after exposure to oxidative stress. Caspase-3 inhibition by Z-DQMD in CFTR-sufficient lung cells mimicked the response profile of increased proteasomal degradation and reduced NF-kappaB activity observed in CFTR-deficient lung cells exposed to oxidative stress. Taken together, these results suggest that functional CFTR Cl(-) channel activity is crucial for regulation of lung proteasomal degradation and NF-kappaB activity in conditions of oxidative stress.
Publication
Journal: International Journal of Mycobacteriology
May/18/2016
Abstract
Tuberculosis (TB) is an ancient disease caused by Mycobacterium tuberculosis (MTB), which remains a major cause for morbidity and mortality in several developing countries. Most drug-resistant MTB clinical strains are resistant to isoniazid (INH), a first-line anti-TB drug. Mutation in KatG, a catalase-peroxidase, of MTB is reported to be a major cause of INH resistance. Normally upon activation by KatG, INH is converted to an active intermediate which has antimycobacterial action in MTB. This INH intermediate in the presence of NADH forms INH-NAD adduct which inhibits inhA (2-trans-enoyl-acyl carrier protein reductase) of MTB, thus blocking the synthesis of mycolic acid, a major lipid of the mycobacterial cell wall. In this docking study, the high binding affinity of INH-NAD adduct towards InhA was observed in comparison with INH alone. In this study, two resistant mutants of KatG (S315T and S315N) were modeled using Modeller9v10 and docking analysis with INH was performed using AutoDock4.2 and the docking results of these mutants were compared with the wild type KatG. Docking results revealed the formation of a single hydrogen (H) bond between the secondary amine nitrogen (-NH) of INH with Thr or Asn residues in place of Serine at 315 position of KatG mutant strains respectively, whereas in the case of the wild type, there was no H-bond formation observed between INH and Ser315. The H-bond formation may prevent free radical formation by KatG in mutant strains thus the development of resistance to the drug. This in silico evidence may implicate the basis of INH resistance in KatG mutant strains.
Publication
Journal: Clinical Rheumatology
December/12/2016
Abstract
Biologic therapies, such as tumor necrosis factor-alpha (TNF-α) blockers, are commonly used to treat rheumatological diseases in childhood. Screening patients for tuberculosis (TB) is highly recommended before starting therapy with TNF-α blockers. Despite appropriate screening, TB still remains a problem in patients receiving anti-TNF therapy in countries where TB is not endemic. TB in anti-TNF-treated patients is often diagnosed late due to altered presentation, and this delay results in high morbidity and mortality with a high proportion of extrapulmonary and disseminated disease. The aim of this study is to show the course of TB disease in children who are on biologic therapy, in an era where many of the children are BCG-vaccinated and TB is intermediately endemic. We recruited 71 patients with several types of inflammatory diseases. Six of them had a positive test result during TB screening and began taking isoniazid (INH) prophylactically. During the 3 years of follow-up, none of these patients developed TB disease. Biologic agents can be safely used in a BCG-vaccinated pediatric population, as long as patients are closely monitored to ensure that any cases of TB will be detected early.
Publication
Journal: Journal of Comparative Pathology
November/17/2014
Abstract
During maturation from fetal to adult testis, both Sertoli cells (SCs) and germ cells (GCs) switch from an immature to a mature immunophenotype. Immature canine SCs express cytokeratins (CKs), desmin (DES), vimentin (VIM), anti-Müllerian hormone (AMH) and inhibin (INH)-α, while mature SCs retain only expression of VIM. Immature GCs express placental alkaline phosphatase (PLAP), which is lost in spermatocytes. Re-expression of markers of immaturity has been observed in human atrophic testes and in human and canine testicular tumours. In human medicine, testicular atrophy is considered a risk factor for testicular cancer. In the present study 13 canine atrophic testes were examined immunohistochemically. VIM was expressed in the SCs of all cases, while CK, DES, INH-α and AMH were expressed in a variable percentage of SCs in two, five, five and eight cases, respectively. PLAP was expressed by single GCs in one case. Markers of immaturity are therefore expressed by SCs and GCs in canine atrophic testes. Similar results were reported previously in canine testicular neoplasia, suggesting that testicular atrophy may represent a risk factor for tumour development in the dog.
Publication
Journal: Journal of Investigational Allergology and Clinical Immunology
July/25/2013
Abstract
BACKGROUND
Hereditary angioedema due to C1 inhibitor deficiency (HAE-C1-INH) has considerable implications for dental health care providers, since dental procedures may trigger severe and even life-threatening episodes. The aim of the present study was to analyze the efficacy and safety of premedication with attenuated androgens (AAs), plasma-derived human C1 esterase inhibitor concentrate (pdhC1INH), or both to prevent the development of upper airway angioedema after dental-oral procedures in patients with HAE-C1-INH.
METHODS
All dental-oral procedures performed on patients with HAE-C1-INH who were followed up at La Paz University Hospital, Madrid, Spain were reviewed. Demographic data, maintenance treatment, preprocedure prophylaxis, disease severity, and occurrence of upper airway angioedema were recorded.
RESULTS
Twenty-four patients (14 male/10 female; mean age, 42.6 years) underwent 66 procedures. Most procedures were performed on patients with severe HAE-C1-INH (20 procedures) or moderate HAE-C1-INH (26 procedures). Only 9 procedures were performed without short-term prophylaxis. Mild upper airway angioedema developed after 3 procedures performed without short-term prophylaxis in patients with minimal or asymptomatic HAE-C1-INH. A statistically significant association was found between development of mild postprocedure upper airway angioedema and lack of maintenance treatment with AA, lack of increased dose of preprocedure AA, and failure to administer preprocedure pdhC1INH (P = .002, Fisher exact test).
CONCLUSIONS
Increased doses of prophylactic AA, administration of pdhC1INH, or both were good options for ambulatory management of dental-oral procedures in patients with HAE-C1-INH. Prophylaxis with pdC1INH or increased doses of AA is advisable before dental-oral procedures, even in patients with low disease severity.
Publication
Journal: Brain and Behavior
June/20/2016
Abstract
BACKGROUND
Development of polyneuropathy (PNP) under treatment for tuberculosis (TB), including isoniazid (INH), is a highly relevant adverse drug effect. The NAT2 acetylation status is a predictor of potential toxic effects of INH. The question as to whether individual risk stratification by genotyping is useful to avoid suffering of patients and to lower costs for the health care system is of considerable clinical importance.
METHODS
After drug treatment for TB, including INH, a 23-year-old man developed severe PNP. During the treatment, laboratory results have been indicating incipient liver and renal injury. Later, molecular genetic analyses were performed and revealed a variation in the NAT2 gene and the c1/c2 genotype of the CYP2E1 gene, both described to contribute to an elevated risk for anti-tuberculostatic-induced liver damages (ATIL).
CONCLUSIONS
The combination of metabolizer genotypes should be taken into account as a cause for toxic effects and the development of PNP. Individual genotyping, performed before medication or at least if an elevation of liver parameters is observed, may reduce the risk of severe cases of PNP by early adjustment of treatment. Our case study indicates that evaluation of individual risk stratification with systematic pharmacogenetic genotyping of metabolizer gene combinations in the context of TB treatment should be addressed in clinical studies with larger cohorts.
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Publication
Journal: Allergy and Asthma Proceedings
February/6/2011
Abstract
Hereditary angioedema (HAE) is a rare, potentially life-threatening disease that manifests as recurrent episodes of nonpruritic swelling that may affect the extremities, face, genitalia, gastrointestinal tract, and/or larynx. HAE is the result of a deficiency of functional C1-esterase inhibitor (C1-INH), a key regulator of the complement, coagulation, and kallikrein-kinin cascades. In HAE patients, overactivation of the kallikrein-kinin cascade results in excessive release of bradykinin, the mediator of the pain and swelling that is characteristic of HAE. Historically, treatment options for HAE have been limited, but newly approved and emerging therapies, such as C1-INH replacement products, a plasma kallikrein inhibitor, and a bradykinin B₂-receptor antagonist, appear to provide safe and effective relief for a significant proportion of patients with HAE. Because they may have therapeutic and practical advantages over existing HAE therapies, the new agents have the potential to improve the overall management of patients with HAE. This article reviews the results from recent clinical trials of these drugs and considers their role in clinical practice.
Publication
Journal: Clinical and Experimental Immunology
August/1/2010
Abstract
Intermittent interleukin (IL)-2 administration to human immunodeficiency virus (HIV)-1 infected patients is well documented and generally used, but there is limited information about the changes of acute-phase protein (APP) levels in response to this treatment. Fifteen patients undergoing highly active anti-retroviral therapy (HAART) treatment, with undetectable viral load, but low CD4+ cell count (<300/microl), have been treated with 3.6 M IU Proleukine administered twice daily by subcutaneous injection over 5 days. C-reactive protein (CRP), D-dimer, C3, C9, C1-inh and alpha-2HS glycoprotein levels were measured immediately before IL-2 administration, as well as on day 5 and 2-3 weeks thereafter. After IL-2 administration, both mean D-dimer and CRP levels increased significantly (P<0.001), but returned (P<0.001) to baseline within the subsequent 2-3 weeks. Alpha-2HS glycoprotein decreased immediately after IL-2 administration. No significant differences were detected in the levels of C3, C9 and C1-inh. A significant, positive correlation (r=0.5178, P=0.0008) was ascertained between the changes of CRP level, measured immediately before as well as 5 days after IL-2 administration, and changes in CD4 T cell counts measured 2-3 weeks before and after treatment, respectively. IL-2 administration induces rapid elevation of two major APPs (CRP, D-dimer). The positive correlation observed between the changes of CRP levels and CD4+ cell counts after IL-2 administration may indicate that the abrupt, but transitory overproduction of CRP might contribute to the CD4+ cell count-increasing effect of the drug and/ or may be associated with serious side effects.
Publication
Journal: Zhonghua yu fang yi xue za zhi [Chinese journal of preventive medicine]
March/2/2009
Abstract
OBJECTIVE
The present study was performed to examine functional and structural impairment of rat sertoli cells following dibutyl phthalate (DBP) exposure.
METHODS
The 6-week-old healthy male Sprague Dawley rats were randomly divided into 4 groups with 16 animals in each group. DBP dissolved in peanut oil was administered by gavage at doses of 0, 250, 500 and 1 000 mg/kg. After 2-week DBP treatment, half of the rats were sacrificed. The rest were killed following 4-week DBP exposure. Follicle stimulating hormone (FSH) was analysed by radioimmunoassay. The relative expression levels of androgen binding protein (ABP) mRNA and inhibin (INH)alpha mRNA were determined by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR). The sertoli cell ultrastructures were observed by using transmission electron microscope (TEM).
RESULTS
FSH levels were increased after 4-week DBP exposure with significance at doses of 250 and 1 000 mg/kg. Sperm head count and daily sperm product were decreased significantly in 500 and 1 000 mg/kg groups. The expression levels of ABP mRNA were 0.89 +/- 0.15, 0.85 +/- 0.23, 0.54 +/- 0.17, 0.52 +/- 0.16 and 0.88 +/- 0.16, 0.61 +/- 0.12, 0.48 +/- 0.15, 0.47 +/- 0.11 for 0, 250, 500 and 1 000 mg/kg after 2- and 4-week DBP treatments respectively with significance at doses of 500 and 1 000 mg/kg (P < 0.01), while the levels of INHalpha mRNA were 0.88 +/- 0.16, 0.61 +/- 0.12, 0.48 +/- 0.15, 0.47 +/- 0.11 and 0.75 +/- 0.19, 0.56 +/- 0.16, 0.53 +/- 0.08, 0.45 +/- 0.10 with significance at all exposure groups (P < 0.01 or P < 0.05). In sertoli cells of rats exposed to 1 000 mg/kg DBP, TEM photos showed more lysosomes in cytoplasm, proliferated and expanded endoplasmic reticulum and nuclei malformation.
CONCLUSIONS
Sertoli cell should be one of the major toxic targets. Impairment of spermatogenesis caused by DBP should be partly due to the suppression of ABP and INHalpha biosynthesis.
Publication
Journal: Diagnostic Microbiology and Infectious Disease
April/6/2010
Abstract
The aim of this study was to evaluate a simple, rapid, and inexpensive colorimetric nitrate reductase assay (NRA) for direct drug susceptibility testing (DST) of Mycobacterium tuberculosis against rifampicin (RIF) and isoniazid (INH). A total of 118 smear-positive specimens were processed from patients on antituberculosis treatment. A comparison was made between the direct NRA of DST with the direct proportion method and with the internationally accepted indirect 1% proportion method as the "gold standard". The sensitivity and specificity of the direct NRA and indirect proportion method were 94% and 98%, and 100% and 98% for RIF and INH, respectively. Excellent agreement was found between the 2 tests with kappa values of 0.92 and 0.98, and P value was less than 0.001 for RIF and INH. The results in most cases were available in 14 days (turnaround time). The direct NRA is a rapid, accurate, simple, and inexpensive method to determine multidrug resistance from sputum. Direct NRA may become an appropriate alternative method, especially for the resource poor settings.
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