BACKGROUND

Traditional remedies employ herbal drugs for the treatment of liver ailments and hepatoprotection. Thus, the present study was designed to evaluate the hepatoprotective effect of "extract of Anacyclus pyrethrum Linn" (APE) against antitubercular drug-induced hepatotoxicity in rats.

METHODS

Group I rats (normal control) received vehicle (1 % CMC), while group II rats (hepatotoxic control) isoniazid (INH) plus rifampicin (RIF) each 50 mg/kg/day po, for 28 days. Group III, IV and V rats were administered with APE 200, APE 400 and silymarin 100 mg/kg/day po, respectively, for 28 days. Concurrently, hepatotoxicity was tried to induce by coadministration of INH and RIF each 50 mg/kg/day po for 28 days in group III, IV and V rats. After 24 h of the last dosing, blood was obtained under light anesthesia and the rats were killed. Hepatoprotective effect was assessed by liver weight, relative liver weight and biochemical parameters such as serum glutamate oxaloacetate transaminase (SGOT), serum glutamate pyruvate transaminase (SGPT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), serum bilirubin, cholesterol, total protein and albumin levels.

RESULTS

Group IV rats showed significant (p<0.01) decrease in SGPT, SGOT, ALP, LDH, cholesterol, serum bilirubin, liver weight and relative liver weight Levels, while significant (p<0.01) increase in final body weight (b. wt.), total protein and albumin levels as compared to group II rats. Hepatoprotective effect of APE 400 mg/kg/day was comparable to that of silymarin 100 mg/kg/day and the hepatic marker levels were also restored. Hepatoprotective effect of APE was well supported by the histopathological results.

CONCLUSIONS

Hydroalcoholic APE root possesses hepatoprotective activity as it exhibited the protective effect against INH plus RIF-induced hepatotoxicity in rats.

Four cases of intra-H-2 recombination were detected during serological screening of 1066 backcross animals produced fromH-2(b)/H-2(t1) heterozygous mice. Three of the intra-H-2 recombinants received theK region fromH-2(t1) and theD region from theH-2(b) parental chromosome. The remaining recombinant received theK region from theH-2(b) parental chromosome and theD region fromH-2(t1). Three of the four recombinants have been developed into inbred lines TBR2, TBR3, and TBR4 and were assigned the haplotype designations at(2), at(3), and at(4). Ss typing revealed that TBR2 and TBR3 originated fromK- S interval crossover events, while the remaining two recombinants resulted from crossing over in theS- D interval.

In cystic fibrosis (CF) lungs, epithelial Na+ channel (ENaC) hyperactivity causes a reduction in airway surface liquid volume, leading to decreased mucocilliary clearance, chronic bacterial infection, and lung damage. Inhibition of ENaC is an attractive therapeutic option. However, ENaC antagonists have failed clinically because of off-target effects in the kidney. The S18 peptide is a naturally occurring short palate lung and nasal epithelial clone 1 (SPLUNC1)-derived ENaC antagonist that restores airway surface liquid height for up to 24 h in CF human bronchial epithelial cultures. However, its efficacy and safety in vivo are unknown. To interrogate the potential clinical efficacy of S18, we assessed its safety and efficacy using human airway cultures and animal models. S18-mucus interactions were tested using superresolution microscopy, quartz crystal microbalance with dissipation, and confocal microscopy. Human and murine airway cultures were used to measure airway surface liquid height. Off-target effects were assessed in conscious mice and anesthetized rats. Morbidity and mortality were assessed in the β-ENaC-transgenic (Tg) mouse model. Restoration of normal mucus clearance was measured in cystic fibrosis transmembrane conductance regulator inhibitor 172 [CFTR(inh)-172]-challenged sheep. We found that S18 does not interact with mucus and rapidly penetrated dehydrated CF mucus. Compared with amiloride, an early generation ENaC antagonist, S18 displayed a superior ability to slow airway surface liquid absorption, reverse CFTR(inh)-172-induced reduction of mucus transport, and reduce morbidity and mortality in the β-ENaC-Tg mouse, all without inducing any detectable signs of renal toxicity. These data suggest that S18 is the first naturally occurring ENaC antagonist to show improved preclinical efficacy in animal models of CF with no signs of renal toxicity.

BACKGROUND

The pathophysiology of subfertility in men with varicocele remains unclear as well as the role of inhibin B (Inh-B) and anti-Müllerian hormone (AMH). The aim of this study was to evaluate Inh-B and AMH concentrations in the spermatic vein of subfertile men with varicocele.

METHODS

A total of 61 subfertile men with varicocele and 31 fertile controls underwent standard andrological evaluation. All subfertile men underwent varicocelectomy, during which blood samples were obtained from the spermatic vein to evaluate Inh-B and AMH concentrations.

RESULTS

Peripheral vein Inh-B concentrations in men with varicocele were lower as compared to controls (52.9 [8.3-136.0) vs 116±9.7 ng/dL, P = .001). There was no difference in AMH concentrations (10.2 [4.4-45.4]) vs 10.4±0.8 pg/dL, P = 0.9). Spermatic vein Inh-B concentrations in men with varicocele were higher compared to those of peripheral vein (87.6±4.4 vs 52.9 [8.3-136.0] ng/dL, P = .001). On the contrary, spermatic vein AMH concentrations were lower compared to those from peripheral vein (8.84 [3.9-47.7] vs 10.2 [4.4-45.4] pg/dL, P = .013).

CONCLUSIONS

Inh-B constitutes a reliable marker of Sertoli cell function as well as spermatogenesis. On the contrary, the clinical significance of AMH in men with varicocele remains to be elucidated.

The mycolic acid compositions of Nocardia rubra and related bacteria grown in media containing different concentrations of antituberculous isonicotinic acid hydrazide (INH) were determined in detail by gas chromatography-mass spectrometry. On the basis of molecular species composition, average carbon numbers of mycolic acids were calculated. In Nocardia rubra, N. lutea and Rhodococcus rhodochrous IFO-13161, the ratio of mycolic to non-mycolic fatty acids and the average carbon numbers of mycolic acids were decreased at the INH concentrations of higher than 1 microgram/ml, paralleling with the significant inhibition of growth. In above three species the synthesis of longer chain mycolic acids (longer than C44 or C46 ) was inhibited more significantly than shorter homologues such as C38 or C40 . In contrast, neither growth inhibition nor change in corynomycolic acid composition was observed in Corynebacteria xerosis and Rhodococcus rhodochrous IFO-13165 at the concentration region of INH up to 100 micrograms/ml. The direct mass fragmentographic analysis of the trimethylsilylated (TMS) derivatives of mycolic acid methyl esters, monitoring [M-15] ions of individual molecular species, revealed that the chain shortening of total mycolic acid molecule by INH occurred more greatly in more highly unsaturated subclasses than in less unsaturated subclasses. Furthermore, mass fragmentographic analysis, monitoring fragment ions (A) and (B), due to straight chain and branched chain alkyl units, respectively, demonstrated the inhibition of mycolic acids was not attributed to the shortening of alpha-alkyl chain, but to the inhibition of chain elongation of C28 to C32 straight chain meromycolic acids. It was also indicated the amounts of trehalose mono- and di- mycolate (cord factor) decreased significantly with the addition of INH (1 to 20 micrograms/ml) in the above strains. From the results obtained above, INH appeared to inhibit the synthesis of mycolic acids longer than C44 or C46 specifically by inhibiting chain elongation or desaturation of precursor long chain fatty acids longer than C28 or C30.

In the rabbit reticulocyte cell-free system, optimal globin synthesis is dependent upon an adequate level of heme. The effect of heme is mediated by an inhibitor of globin synthesis initiation termed HCR. In addition to marked inhibition of total globin synthesis, HCR results in a decreased alpha/beta globulin synthesis ratio. We describe here the use of INH as a relatively nontoxic inhibitor of heme synthesis in intact rabbit reticulocytes with a resultant inhibition of globin synthesis. In parallel with the inhibition of globin synthesis in reticulocytes, an inhibitor of globin synthesis in the hemin-supplemented cell-free system is generated. No INH-induced alterations in alpha/beta synthesis ratio could be found in "stress" reticulocytes from phenylhydrazine-treated rabbits, but "normal" reticulocytes from untreated rabbits showed a decreased alpha/beta ratio. Inhibition of heme synthesis and the resulting decrease in globin synthesis and intracellular hemoglobin concentration may have application as a potential treatment of homozygous sickle cell disease.

A low molecular inhibitor (LMW-INH) of the alternative pathway activation was isolated form healthy human urine. Its molecular weight was slightly higher than 1000. LMW-INH inhibited C3 convertase formation in fluid phase, on sheep erythrocytes and on zymosan particles. In contrast with beta 1H globulin LMW-INH showed no effect on the C3b binding site for B, and it inhibited the activation of CVF.B complex by D only when LMW-INH was simultaneously present with D. These results indicate that the reaction mechanism of LMW-INH is different from that of beta 1H globulin.

The use of biotinylated ligands for the flow cytometric detection of cell surface receptors has become a popular alternative to radioreceptor assays. Although the biotinylation of a protein is a relatively mild chemical reaction several reports have mentioned the fact that the number and location of biotin moieties coupled to amino groups of a protein can alter its physicochemical properties and impair biological activity. In the present study we show for a variety of biotinylated functionally unaltered ligands that biotinylation by N-hydroxysuccinimide (NHS) esters of biotin can induce a binding to cell surfaces, which is not specific for the respective unlabelled ligand. C1q, C1 inhibitor (C1-INH), alpha 1-antitrypsin (AT), ovalbumin (OV), transferrin and soybean trypsin inhibitor (STI) were labelled with S-NHS-LC-biotin and activated C1s (C1s) with NHS-biotin. Biotinylation of C1q, C1s and C1-INH exerted negligible effects on biological function, antigenicity or electrophoretic mobility but when labelled and unlabelled proteins were assayed for binding to monocytic U937 cells, promyelocytic HL-60 cells, monocytes and granulocytes, a remarkable binding was observed for biotinylated C1q, C1-INH and C1s. In contrast, no binding was observed when we used unlabelled C1q, C1s and C1-INH and employed specific antibodies, alpha-mouse-FITC or alpha-rabbit-FITC for detection. Increasing molar ratios of biotin-to-protein (B : P) for biotinylated AT, OV and STI evoked increased fluorescence intensities of the cells. Most importantly the unlabelled ligands did not compete for cell binding with their biotinylated derivatives, with the exception of transferrin. Preincubation of the cells with an excess of free d-biotin did not reduce binding of biotinylated proteins, thus excluding a potential involvement of biotin receptors. Hydrophobic interaction chromatography revealed a remarkable increase in hydrophobicity of the biotinylated proteins compared to their unlabelled counterparts, suggesting that the biotinylation-induced binding is due to increased hydrophobicity. Our findings indicate that biotinylation by the common amino acid esterification method may be critical for proteins if they are to be used as ligands for receptor binding studies.

Isoniazid (INH) is recommended for tuberculosis prophylaxis in non-liver transplant recipients. However, there is a great reluctance to prescribe this agent for liver transplant candidates and recipients due to the risk of precipitating further hepatic decompensation. We analyzed the records of liver transplantation candidates undergoing a purified protein derivative (PPD) test (tuberculosis skin test) between 2008 and 2010. Patients with no respiratory symptoms, PPD test>> 10 mm, and normal chest radiography were diagnosed as latent tuberculosis and prescribed INH (300 mg) per day for 6 months. The 191 patients submitted to a PPD test and those on tuberculosis prophylaxis underwent blood tests and clinical evaluations monthly to detect hepatotoxicity of patients The 33 subjects (17.2%) with a PPD test ≥ 10 mm displayed an average model for end-stage liver disease score of 20 (range: 9-29) and child-Pugh A/B score. The main causes for liver disease were chronic hepatitis C, hepatocellular carcinoma, and alcohol abuse. Among 27 patients who received INH, 18 (66.6%) completed 6 months of prophylaxis. Eight who had shorter treatment courses of 2 to 4 months had undergone transplantation. One patient had to stop treatment because of clinical decompensation due to spontaneous bacterial peritonitis without a transaminases elevation. Six patients did not receive INH: previous tuberculosis treatment, transplantation before initiating prophylaxis, or removal from the liver candidacy list. No patient showed clinical decompensation or laboratory abnormalities associated with use of INH. The average values of alanine aminotransferase pre- and posttreatment were similar (69 and 72 U/l respectively), demonstrating that tuberculosis prophylaxis with INH was safe for liver transplant candidates.

In vertebrates, enhanced translation of mRNAs in oocytes and early embryos entering M-phase is thought to occur through polyadenylation, involving binding, hyperphosphorylation and proteolytic degradation of Aurora-activated CPEB. In starfish, an unknown component of the oocyte nucleus is required for cyclin B synthesis following the release of G2/prophase block by hormonal stimulation. We have found that CPEB cannot be hyperphosphorylated following hormonal stimulation in starfish oocytes from which the nucleus has been removed. Activation of Aurora kinase, known to interact with protein phosphatase 1 and its specific inhibitor Inh-2, is also prevented. The microinjection of Inh-2 restores Aurora activation, CPEB hyperphosphorylation and cyclin B translation in enucleated oocytes. Nevertheless, we provide evidence that CPEB is in fact hyperphosphorylated by cdc2, without apparent involvement of Aurora or MAP kinase, and that cyclin B synthesis can be stimulated without previous degradation of phosphorylated CPEB. Thus, the regulation of cyclin B synthesis necessary for progression through meiosis can be explained by an equilibrium between CPEB phosphorylation and dephosphorylation, and both aspects of this control may rely on the sole activation of Cdc2 and subsequent nuclear breakdown.

<A<em>b</em>stractText>Ze<em>b</em>rafish inflammation models were used to evaluate the anti-inflammatory activity of isoniazid (<em>INH</em>) and preliminarily investigate the underlying mechanism.</A<em>b</em>stractText><p><div>(<em>b</em>)METHODS</<em>b</em>)</div>Local, acute, and systemic ze<em>b</em>rafish inflammation models were esta<em>b</em>lished <em>b</em>y tail cutting, copper sulfate (CuSO<su<em>b</em>)4</su<em>b</em>)), and lipopolysaccharide (LPS) endotoxin treatments, respectively, to evaluate the anti-inflammatory activity of <em>INH</em>. Ze<em>b</em>rafish in the inflammatory state were exposed to different concentrations of <em>INH</em> (1, 2, and 4 mM) for 72 h to o<em>b</em>serve changes in the migration and accumulation of inflammatory cells and measure the reactive oxygen species (ROS) content in ze<em>b</em>rafish after <em>INH</em> treatment. The transcription levels of inflammation-related genes in ze<em>b</em>rafish from all groups were measured using real-time polymerase chain reaction (RT-PCR).</p><A<em>b</em>stractText>Compared to those o<em>b</em>served in the control inflammation model group, the num<em>b</em>ers of migrated and accumulated inflammatory cells in ze<em>b</em>rafish in the <em>INH</em>-treated group significantly decreased. <em>INH</em> significantly decreased the ROS content induced <em>b</em>y LPS. Compared to that o<em>b</em>served in the LPS model group, <em>INH</em> at 1 and 2 mM significantly increased the expression of PPARγ and inhi<em>b</em>ited the expression of NF-κB, iκ<em>b</em>αa, and AP-1 as well as the inflammatory factors TNF-ɑ, TGF-<em>β</em>, IL-1<em>b</em>, and COX-2.</A<em>b</em>stractText><A<em>b</em>stractText>In this study, different ze<em>b</em>rafish inflammation models were used to confirm that <em>INH</em> has anti-inflammatory activity. The associated mechanism may occur through the inhi<em>b</em>ition of ROS release, activation of PPARγ expression, inhi<em>b</em>ition of the transcriptional regulatory activity of NF-κB and AP-1, and reduction of <em>INH</em> inflammatory factor expression to relieve inflammation. The results of this study provide references for the clinical application of <em>INH</em>.</A<em>b</em>stractText>

<p><div>(<em>b</em>)BACKGROUND</<em>b</em>)</div>Distri<em>b</em>ution of <i>N-acetyltransferase2</i> (<i>NAT2</i>) polymorphisms varies considera<em>b</em>ly among different ethnic groups. Information on <i>NAT2</i> single-nucleotide polymorphisms in South African population is limited. We investigated <i>NAT2</i> polymorphisms and their effect on isoniazid pharmacokinetics in Zulu <em>b</em>lack HIV-infected South Africans in Dur<em>b</em>an, South Africa.</p><p><div>(<em>b</em>)METHODS</<em>b</em>)</div>HIV-infected participants with culture-confirmed pulmonary tu<em>b</em>erculosis (TB) were enrolled from two unrelated studies. Culture-confirmed participants were genotyped for <i>NAT2</i> polymorphisms 282C>T, 341T>C, 481C>T, 857G>A, 590G>A and 803A>G using Life Technologies pre-validated Taqman assays (Life Technologies, Paisley, UK). Participants underwent sampling for determination of plasma isoniazid and <i>N</i>-acetylisoniazid concentrations.</p><p><div>(<em>b</em>)RESULTS</<em>b</em>)</div>Amongst the 120 patients, 63/120 (52.5%) were slow meta<em>b</em>olisers (<i>NAT2</i>*5/*5), 43/120 (35.8%) had intermediate (<i>NAT2*5/12</i>), and 12/120 (11.7%) had rapid genotype (<i>NAT2*4/*11</i>, <i>NAT2*11/12</i> and <i>NAT2*12/12</i>). NAT2 alleles in this study were *4, *5C, *5D, *5E, *5J, *5K, *5KA, *5T, *11A, *12A/12C and *12M. NAT2*5 was the most frequent allele (70.4%) followed <em>b</em>y <i>NAT2*12</i> (27.9%). 34/40 had <em>b</em>oth PK results and <i>NAT2</i> genotyping results. The median area under the concentration-time-curve to infinity (AUC<su<em>b</em>)0-</su<em>b</em>)<su<em>b</em>)∞</su<em>b</em>)) interquartile range (IQR) was 7.81 (5.87 - 16.83) μg/ml/hr and maximum concentration (Cmax) 3.14 μg/ml (2.42 - 4.36) μg/mL. Individual polymorphisms were not equally distri<em>b</em>uted, with some represented in small num<em>b</em>ers. Genotype did not correlate with phenotype, rapid genotype showing higher AUC<su<em>b</em>)0-∞</su<em>b</em>) than slow <em>b</em>ut not significant, p=0.43.</p><A<em>b</em>stractText>There was high prevalence of slow followed <em>b</em>y intermediate then rapid acetylator genotypes. The poor concordance <em>b</em>etween genotype and phenotype suggests that other factors or genetic loci influence <em>INH</em> meta<em>b</em>olism, and warrants further investigation in this population.</A<em>b</em>stractText>

METHODS

The bioavailability of rifampicin (RMP) decreases by ∼30% on interaction with isoniazid (INH) in stomach acid conditions, which can result in the development of drug resistance and treatment failure.

OBJECTIVE

To compare the bioavailability in healthy volunteers of five anti-tuberculosis fixed-drug combinations (FDCs) used in China (formulations A-E) containing RMP and INH against single-drug formulations taken as reference.

METHODS

Two- or three-period, two- or three-sequence crossover study of drugs.

RESULTS

Only RMP formulation E passed the bioequivalence criteria, with 90% confidence intervals for the log-transformed ratios of AUC₀₋₂₄, AUC₀₋∞, and Cmax of respectively 89.9-103.7, 89.6-102.2 and 87.7-107.9. For INH, formulations A, B, C and D passed the bioequivalence test, but not product E, where the 90%CIs of the log-transformed ratios of AUC₀₋₂₄, AUC₀₋∞, and Cmax were respectively 85.2-100.7, 85.2-100.7 and 73.8-100.9.

CONCLUSIONS

According to the results of the bioequivalence analysis carried out in this study, RMP formulations A, B, C and D were not within the acceptable range and only formulation E passed the bioequivalence criteria of 80-125%. In comparison, four-test INH formulations (A, B, C and D) were bioequivalent to the corresponding single-drug formulation, while product E failed in the bioequivalence criteria.

Phenolcarboxylic acid antioxidants do not act in vivo as radical-scavengers in isolation, but rather together with GSH (glutathione), a coantioxidant, they constitute an intricate antioxidant network. Caffeic acid, p-coumaric acid, ferulic acid and chlorogenic acid with or without 2-mercaptoethanol (ME), as a substitute for GSH, was investigated by the induction period (IP) method for polymerization of methyl methacrylate (MMA) initiated by thermal decomposition of 2,2'-azobisisobutyronitrile (AIBN, a source of alkyl radicals, R(.)) and benzoyl peroxide (BPO, a source of peroxy radicals, PhCOO(.)) using differential scanning calorimetry (DSC). Upon PhCOO(. )radical scavenging, the stoichiometric factors (n, number of free radical trapped by one mole of antioxidant) for caffeic acid, ferulic acid, p-coumaric acid and chlorogenic acid were 2.4, 1.8, 1.7 and 0.9, whereas upon R(.) radical scavenging, the corresponding values were 1.3, 1.2, 1.0 and 0.8, respectively. Antioxidants with n values close to 2 suggest the stepwise formation of semiquinone radicals and quinones. By contrast, those with n values close to 1 suggest the formation of dimers after single-electron oxidation, possibly due to recombination of corresponding aryloxy radicals. The ratio of the rate constant of inhibition to that of propagation (k(inh)/k(p)) declined in the order chlorogenic acid>> p-coumaric acid>> ferulic acid>> caffeic acid. The ratio of the observed IP for the phenolcarboxylic acid/2-mercapto-ethanol (ME) mixture (1:1 molar ratio) (A) to the calculated IP (the simple sum of phenol acid antioxidant and ME) (B) was investigated. Upon R(.) scavenging, the caffeic acid or p-coumaric acid/ME mixture was A/B>> 1, particularly the former was 1.2, suggesting a synergic effect. By contrast, upon PhCOO(.) scavenging, the corresponding mixture was A/B < 1, particularly the latter was 0.7, suggesting an antagonistic effect. Upon both radicals scavenging, the A/B for the ferulic acid or chlorogenic acid/ME mixture was approximately 1. The reported beneficial antioxidant, anti-inflammatory and anticancer effects of caffeic acid and p-coumaric acid may be related to their prooxidant-antioxidant balance in the presence of GSH.

[reaction: see text] Rate constants for hydrogen-atom transfer (HAT) from bilirubin dimethyl ester (BRDE) and biliverdin dimethyl ester (BVDE) to peroxyl radicals during inhibited autoxidation of styrene initiated by azo-bisisobutyronitrile (AIBN) were k(inh)(BRDE) = 22.5 x 10(4) and k(inh)(BVDE) = 10.2 x 10(4) M(-1) s(-1), and the stoichiometric factors (n) were 2.0 and 2.7, respectively. A synthetic tetrapyrrole (bis(dipyrromethene)) containing the alpha-central (2,2') CH2 linkage gave k(inh) = 39.9 x 10(4) M(-1) s(-1) and n = 2.3, whereas the beta-linked (3,3') isomer was not an active antioxidant. Several dipyrrinones were synthesized as mimics of the two outer heterocyclic rings of bilirubin and biliverdin. The dipyrrinones containing N-H groups in each ring were active antioxidants, whereas those lacking two such "free" N-H groups, such as N-CH3 dipyrrinones and dipyrromethenes, did not exhibit antioxidant activity. Overall, the relative k(inh) values compared to those of phenolic antioxidants, 2,6-di-tert-butyl-4-methoxyphenol (DBHA) and 2,6-di-tert-butyl-4-methylphenol (BHT), were 2,2'-bis(dipyrromethene)>> BRDE>> DBHA>> dipyrrinones>> BVDE>> BHT. This general trend in antioxidant activities was also observed for the inhibited autoxidation of cumene initiated by AIBN. Chemical calculations of the N-H bond dissociation enthalpies (BDEs) of the typical structures support a HAT mechanism from N-H groups to trap peroxyl radicals. Intramolecular hydrogen bonding of intermediate nitrogen radicals has a major influence on the antioxidant activities of all compounds studied. Indeed, chemical calculations showed that the initial nitrogen radical from a dipyrrinone is stabilized by 9.0 kcal/mol because of H-bonding between the N-H remaining on one ring and the ground-state pyrrolyl radical of the adjacent ring in the natural zusammen structure. The calculated minimum structure of bilirubin shows strong intramolecular H-bonding of the N-H groups with carbonyl groups resulting in the known "ridge-tile" structure which is not an active HAT antioxidant. The calculated minimum structure of biliverdin is planar. BRDE is readily converted into BVDE by reaction with the electron-deficient DPPH* radical under argon in chlorobenzene. An electron-transfer mechanism is proposed for the initiating step in this reaction, and this is supported by the relatively low ionizing potential of a model dipyrrole representing the two central rings of bilirubin.

<A<em>b</em>stractText>In patients with pulmonary arterial hypertension (PAH), it remains unknown if the response to the acute pulmonary vasoreactivity test changes over time and determines prognosis.</A<em>b</em>stractText><A<em>b</em>stractText>We included PAH patients who underwent two right heart catheterizations (RHC) with acute vasoreactivity challenge using <em>inh</em>aled nitric oxide (NO). The hemodynamic response was assessed <em>b</em>y a<em>b</em>solute or percentage change in mean pulmonary artery pressure (mPAP) or pulmonary vascular resistance (PVR).</A<em>b</em>stractText><A<em>b</em>stractText>We included 54 patients, age 51 ± 17 years, and 44 (82%) female. The median (IQR) time <em>b</em>etween the two RHC was 24.5 months (14.8-42 months). The percentage drop in mPAP was less pronounced in the second RHC (- 8.6 ± 8.1 versus - 12.3 ± 13.8 mmHg, p = 0.02). A total of 8 (14%) patients met criteria for a positive vasodilatory test during the first RHC <em>b</em>ut only 1 during the second. Patients with increased vasoreactivity at second RHC were more likely to receive (a) treatment with phosphodiesterase-5 <em>inh</em>i<em>b</em>itors (PDE5-<em>inh</em>) at first RHC (56% versus 27%, p = 0.04) and (<em>b</em>) more PAH-specific medications <em>b</em>y second RHC (2.3 ± 0.8 versus 1.8 ± 0.9, p = 0.03). Cox survival analysis showed that change in mPAP or PVR during vasodilatory challenge at or <em>b</em>etween the first and second RHC had no impact on survival.</A<em>b</em>stractText><A<em>b</em>stractText>Pulmonary vascular reactivity to <em>inh</em>aled NO might decrease over time; however, there is great varia<em>b</em>ility among patients. The use of PDE5-<em>inh</em> at first RHC and num<em>b</em>er of PAH-specific treatments <em>b</em>y the second RHC were associated with an improvement in pulmonary vasoreactivity over time.</A<em>b</em>stractText>

<sec id="st1"> <title>BACKGROUND</title> Abbott RealTime MTB RIF/INH Resistance (RT RIF/INH) is a new assay for the detection of resistance to rifampicin (RIF) and isoniazid (INH) in tuberculosis (TB) patients. </sec> <sec id="st2"> <title>OBJECTIVE</title> To evaluate the capacity of RT RIF/INH to detect resistance-associated mutations in target genes. </sec> <sec id="st3"> <title>METHODS</title> A total of 311 Mycobacterium tuberculosis strains that had been pre-characterised using genotypic methods (GenoType^® MTBDRplus, Sanger sequencing) and phenotypic drug susceptibility testing were subjected to DNA extraction on Abbott msp and analysed using RT RIF/INH. Detection of heteroresistant mutations was studied with artificial mixtures of wild-type and mutant DNA. </sec> <sec id="st4"> <title>RESULTS</title> Overall sensitivity and specificity values of RT RIF/INH to detect resistance were respectively 87.2% and 98.4% for RIF and respectively 90.1% and 99.2% for INH. The capacity of RT RIF/INH to detect specific mutations was 100% for katG, inhA and frequent rpoB mutations, and 76% for rare rpoB mutations. Among the latter, two rare mutations were not consistently detected. With heteroresistant samples, RT RIF/INH reported resistance if samples contained at least 75-90% of mutant DNA. </sec> <sec id="st5"> <title>CONCLUSION</title> RT RIF/INH is a reliable high-throughput assay for the detection of RIF and INH resistance markers. The ability to detect INH resistance also may be of benefit in areas with high rates of INH-resistant, non-multidrug-resistant TB. </sec>.

Background & Aim: Diallyl trisulfide (DATS) has been verified to ameliorate hepatotoxicity induced by many drugs, but the protective actions of isoniazid (INH) and rifampicin (RFP) have not been reported. We attempted to elucidate the potential effects and mechanisms of DATS against INH&RFP-caused hepatotoxicity. Methods: Male Kunming mice weighing 18-22 g were divided into 6 groups. For the hepatic-protective study, DATS (10 mg per kg, 20 mg per kg, and 40 mg per kg bw, respectively) was orally administered two hours before the INH&RFP (100 mg per kg, 100 mg per kg bw, respectively) treatments. After 11 days of treatment, 10 mice in each group were taken for the carbon clearance test, while the other 10 mice were sacrificed for the collection of serum and livers for further measurements, including the levels of serum alanine aminotransferase (ALT), aspartate transaminase (AST) and total bilirubin (T.Bili), the liver index, and liver histopathological examination. Malondialdehyde (MDA), glutathione (GSH), and the level of interleukin 1-β (IL-1-β) were measured, the carbon clearance test was performed and the immunohistochemistry of F4/80 marker for activated Kupffer cells (KCs) was analyzed to investigate potential mechanisms. Results: DATS co-administration significantly inhibited the increase of liver index and elevation of serum ALT, AST and T.Bili levels induced by INH&RFP, as well as improved the hepatocellular structure. The further mechanistic studies demonstrated that DATS co-administration counteracted INH&RFP-induced oxidative stress in mice, which was illustrated by the restoration of GSH levels, and the reduction of MDA levels in the liver. Furthermore, DATS co-administration reactivated the KCs inhibited by INH&RFP, which was illustrated by the increase of carbon phagocytosis, and the restoration of the number of activated KCs and IL-1-β levels in the liver. Conclusion: DATS effectively protected the liver against INH&RFP-induced hepatotoxicity, which might be due to its antioxidant effect and enhancement of KCs' activities.

The antigen 85 (Ag85) complex of Mycobacterium tuberculosis represents a promising candidate as a novel drug target and pathogenesis factor. Ag85 comprises three proteins Ag85A, B and C, (encoded by the genes fbpA, B, and C), which participate in cell wall biosynthesis, and interact with the host macrophage as fibronectin-binding proteins (fbps). Ag85 is also involved in the response to isoniazid (INH) treatment. The objective of this study was to identify potential fbp gene activators involved in the over-expression of fbp genes in response to INH. The biotinylated upstream promoter regions of fbpA and fbpC were used together with streptavidin-coated magnetic beads in DNA-binding assays, to isolate proteins with high-binding affinities from cytosolic extracts of INH-treated M. tuberculosis. Resolution of the DNA-binding proteins by 1D SDS-PAGE revealed 6 proteins with high-affinity for the fbpA promoter, and 7 with specificity the fbpC promoter. Mass spectrometric analyses [LC-ES(MS/MS)] identified proteins associated with drug resistance and stress/treatment responses, intermediary metabolism and cellular division, hypothetical proteins including a member of the MarR family of bacterial transcriptional regulators. The DNA-binding MarR protein shows potential as an authentic activator of fbp genes and functional validation of this factor is warranted.

Hereditary angioedema (HAE) is an autosomal dominant disorder defined by a deficiency of functional C1 esterase inhibitor (C1-INH). Acquired angioedema is due to either consumption (type 1) or inactivation (type 2) of CI-INH. Both HAE and acquired angioedema can be life-threatening. Of the three types of HAE, type 1 is most common, occurring in approximately 85% of patients and characterized by decreased production of C1-INH, which results in reduced functional activity to 5-40% of normal. Type 2 occurs in 15% of cases; C1-INH is detectable in normal or elevated quantities but is dysfunctional. Also, HAE with normal CI-INH (previously called type 3 HAE) is rare and characterized by normal complement studies. Specific genetic mutations have been linked to factor XII, angiopoietin-1, and plasminogen gene. Patients with unknown mutations are classified as unknown. The screening test for types 1 and 2 is complement component C4, which is low to absent at times of angioedema and during quiescent periods. A useful test to differentiate HAE from acquired angioedema is C1q protein, which is normal in HAE and low in acquired angioedema. The management of HAE has been transformed with the advent of disease-specific therapies. On-demand therapy options include plasma and recombinant C1-INH for intravenous infusion; ecallantide, an inhibitor of kallikrein; and icatibant, a bradykinin β₂ receptor antagonist, both administered subcutaneously. For long-term prophylaxis, intravenous or subcutaneous C1-INH enzyme replacement and lanadelumab, a monoclonal antibody against kallikrein that is administered subcutaneously, are effective agents.

The nitrogen-containing imine or hydrazone linked covalent organic frameworks (COFs) are poorly luminescent due to the fluorescence quenching <em>b</em>y nitrogen atoms in the linkages, even if highly luminescent units and linkers are employed. The fluorescence quenching pathway to prevent linkage-originated to mitigate the inherent limitations of the linkage is a promising method for luminescent COFs. The generation of N^- <em>b</em>y deprotonation of the N-H unit eliminates the electron transfer from N lone pair to COF ((<em>b</em>)TpPa-1</<em>b</em>)) and enhances the luminescence. In this work, (<em>b</em>)TpPa-1</<em>b</em>) achieved turn-on luminescence response with good sensitivity and reproduci<em>b</em>ility toward triethylamine (TEA) vapor in the process of deprotonation. The fa<em>b</em>ricated detector offers a via<em>b</em>le approach for sensing ppm-level TEA, which can remind people to take timely measures to reduce the environmental hazards caused <em>b</em>y TEA. The fluorescent sensor (<em>b</em>)TpPa-1@LE</<em>b</em>) constructed <em>b</em>y the products of (<em>b</em>)TpPa-1</<em>b</em>) and TEA can quantitatively trace <em>b</em>iomarker methylglyoxal (MGO) for dia<em>b</em>etes mellitus diagnosis in serum system. Furthermore, using TEA and MGO as input signals and the two fluorescence emissions G476 and Y525 as output signals, an advanced analytical device <em>b</em>ased on two Boolean logic gates with <em>INH</em> and AND function is constructed. This work provides a new strategy for improving the weak luminescence of COF in aqueous solution and realizes selective response to <em>b</em>iomarker (MGO) for dia<em>b</em>etes mellitus diagnosis.

Relapsing fever (RF) is claimed a neglected arthropod-borne disease caused by a number of diverse human pathogenic Borrelia (B.) species. These RF borreliae are separated into the groups of tick-transmitted species including B. duttonii, B. hermsii, B. parkeri, B. turicatae, B. hispanica, B. persica, B. caucasica, and B. myiamotoi, and the louse-borne Borrelia species B. recurrentis. As typical blood-borne pathogens achieving high cell concentrations in human blood, RF borreliae (RFB) must outwit innate immunity, in particular complement as the first line of defense. One prominent strategy developed by RFB to evade innate immunity involves inactivation of complement by recruiting distinct complement regulatory proteins, e.g., C1 esterase inhibitor (C1-INH), C4b-binding protein (C4BP), factor H (FH), FH-like protein-1 (FHL-1), and factor H-related proteins FHR-1 and FHR-2, or binding of individual complement components and plasminogen, respectively. A number of multi-functional, complement and plasminogen-binding molecules from distinct Borrelia species have previously been identified and characterized, exhibiting considerable heterogeneity in their sequences, structures, gene localization, and their capacity to bind host-derived proteins. In addition, RFB possess a unique system of antigenic variation, allowing them to change the composition of surface-exposed variable major proteins, thus evading the acquired immune response of the human host. This review focuses on the current knowledge of the immune evasion strategies by RFB and highlights the role of complement-interfering and infection-associated molecules for the pathogenesis of RFB.

Keywords: Borrelia; adaptive immunity; antigenic variation; complement; immune evasion; innate immunity; relapsing fever; spirochetes.

A 70-year-old woman complained of mild shortness of breath. Laboratory findings revealed pancytopenia, positive lupus anticoagulant and severe hypocomplementemia without anti-nuclear or anti-DNA antibodies. After the failure of prednisolone treatment, an acquired C1-esterase inhibitor (C1-INH) deficiency was diagnosed. There were no episodes of angioedema or deep vein thrombosis. Three months later, extreme splenomegaly was detected. Lymph node biopsy suggested splenic marginal zone B-cell lymphoma. Acquired C1-INH deficiency due to a lymphoproliferative disorder should be considered as a possible diagnosis for patients with severe hypocomplementemia.

<p><div>(<em>b</em>)Background</<em>b</em>)</div>In order to shorten the course of treatment and its effectiveness, it is essential to gain an in-depth insight into the drug resistance mechanisms of <i>Myco<em>b</em>acterium tu<em>b</em>erculosis</i> (<i>M. tu<em>b</em>erculosis</i>).</p><p><div>(<em>b</em>)Methods</<em>b</em>)</div>In this study, we evaluated the contri<em>b</em>ution of 26 drug efflux pumps plus target gene mutations to the drug resistance levels in multi-drug resistant (MDR)/pre-extensively drug-resistant (pre-XDR)/extensively drug-resistant (XDR) and mono-drug resistant clinical isolates of <i>M. tu<em>b</em>erculosis</i>. The panels of 25 <i>M. tu<em>b</em>erculosis</i> clinical strains were characterized for drug resistance-associated mutations with whole-genome sequencing and anti<em>b</em>iotic profiles in the presence and a<em>b</em>sence of efflux inhi<em>b</em>itor verapamil (VP).</p><p><div>(<em>b</em>)Results</<em>b</em>)</div>Different MICs were o<em>b</em>served for the same target gene mutations. Out of the 16 MDR/pre-XDR/XDR isolates, 6 (37.5%) and 3 (18.8%) isolates demonstrated a significant decrease in rifampicin (RIF) MIC and isoniazid (<em>INH</em>) MIC due to the VP exposure (64 μg/mL), respectively. Suscepti<em>b</em>ility to RIF was fully restored in two isolates after VP exposure. Moreover, the efflux pump genes of <i>Rv2938, Rv2936, Rv1145, Rv1146, Rv933, Rv1250, Rv876</i>, <i>Rv2333, Rv2459, Rv849,</i> and <i>Rv1819</i> were overexpressed in the presence of anti-TB drugs, showing the contri<em>b</em>ution of these efflux pumps to the overall resistance phenotype.</p><A<em>b</em>stractText>Our results clearly showed that efflux systems, <em>b</em>esides spontaneous mutations, play a role in the development of <em>INH</em>/RIF resistance. In addition, although VP was effective in reducing the expression of some efflux pumps, it was not very successful at the phenotypic level.</A<em>b</em>stractText>