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PubMed2026

Pathomics-based machine learning models for predicting METTL5 expression and prognosis in lung adenocarcinoma.

BACKGROUND: METTL5, an N6-methyladenosine (m6A) RNA methyltransferase, has been implicated in tumor progression, but its prognostic value and non-invasive prediction in lung adenocarcinoma (LUAD) remain unclear. This study aimed to develop a pathomics-based machine learning model to predict METTL5 expression from histopathological images and evaluate its prognostic significance in LUAD. METHODS: A total of 327 LUAD patients from The Cancer Genome Atlas (TCGA) with matched hematoxylin and eosin (H&E) slides, transcriptomic, and clinical data were included and randomly divided into training and validation sets (7:3). Quantitative histopathological features were extracted using PyRadiomics. Feature selection was performed via maximum relevance minimum redundancy (mRMR) and recursive feature elimination (RFE), followed by construction of a Gradient Boosting Machine (GBM) model. A pathomics score (PS) was generated to assess prognostic relevance. Survival analyses, gene set variation analysis (GSVA), tumor mutational burden (TMB), immune infiltration analysis, and in vitro functional assays were conducted. RESULTS: METTL5 overexpression was independently associated with poor overall survival [hazard ratio (HR) =1.637, P=0.007]. The model achieved good predictive performance [area under the curve (AUC) =0.847 in the training set and 0.752 in the validation set]. High PS was significantly associated with worse survival and remained an independent prognostic factor (HR =1.563, P=0.03). Elevated PS correlated with altered metabolic pathways, increased TMB, and immune microenvironment changes. METTL5 knockdown reduced proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) in A549 cells. CONCLUSIONS: The pathomics-based model accurately predicts METTL5 expression and provides prognostic stratification in LUAD, supporting its potential as a practical imaging-derived biomarker.

Methyltransferase-like 5↗

PubMed2026

Systematic characterization of neurotransmitter receptor dysregulation identifies a neural-related prognostic signature associated with biochemical recurrence in prostate cancer.

BACKGROUND: The nervous system is increasingly recognized to play a critical role in tumor initiation and progression. Central to this complex relationship are the interactions between neurotransmitters secreted by neurons and their receptors (neurotransmitter receptors, NTRs) expressed on cancer cells, which activate multiple intracellular signaling pathways. However, the spectrum of NTR dysregulation and its association with biochemical recurrence (BCR) in prostate cancer (PCa) has not been explored. Therefore, the aim of this study was to fill this gap. METHODS: We systematically characterized the expression profiles of 130 NTR genes by integrating bulk and single-cell transcriptomic data. Consistently dysregulated NTR (cdNTR) genes were identified and used to construct a PCa signature (PCaSig) using elastic-net regression. The robustness of PCaSig was evaluated across three independent cohorts. In addition, the associations of PCaSig with clinicopathological characteristics, genomic alterations, tumor immune-related characteristics, and biological pathways were comprehensively investigated. RESULTS: Thirteen cdNTR genes with strong cell-type specificity, particularly in luminal epithelial cells, were identified. PCaSig robustly stratified patients into distinct BCR risk groups across multiple independent cohorts and remained an independent predictor after adjustment for clinicopathological factors. High PCaSig scores were associated with aggressive clinicopathological features, elevated tumor mutation burden (TMB), suppression of neurotransmitter-related signaling, and activation of cell-cycle and immune-related pathways. Notably, PCaSig refined prognostic stratification regardless of TMB status and was associated with distinct immune-related characteristics, including immune checkpoint expression and immune cell infiltration. Incorporation of PCaSig into a clinical nomogram significantly improved prognostic accuracy and clinical net benefit. CONCLUSIONS: These findings establish NTR dysregulation as a previously underappreciated dimension of PCa and support PCaSig as a clinically relevant tool for personalized management.

Neurotransmitter receptor (NTR)↗

PubMed2026

Integrated bioinformatics analyses for GSDMB in carcinogenesis and progression of bladder cancer.

BACKGROUND: Emerging evidence suggests that pyroptosis influences the development of various diseases. Gasdermin B (GSDMB), an intracellular protein that executes pyroptosis, has recently attracted attention for its potential role in tumor biology. However, its specific function in bladder cancer (BLCA) remains unclear. Therefore, this study aimed to investigate the potential role of GSDMB in the carcinogenesis and prognosis of BLCA patients. METHODS: Mendelian randomization (MR) studies were conducted to examine relationships between the expression of GSDMB and BLCA with expression quantitative trait loci (eQTL) data. Then, GSDMB mRNA expression data and clinical characteristics of BLCA patients were retrieved from The Cancer Genome Atlas (TCGA) database. Cox regression was used to explore the relationship between GSDMB mRNA expression and patients' survival. Additionally, the correlation between GSDMB and the immune microenvironment, tumor mutational burden (TMB), tumor microenvironment (TME), and drug sensitivity in BLCA was examined. RESULTS: According to MR analysis based on eQTLs, GSDMB mRNA expression has positive causal effects on bladder carcinogenesis and the need for bladder surgery (P<0.05). The analyses of TCGA demonstrated an increased expression of GSDMB in BLCA tissues, correlating with improved patient survival. Additionally, elevated GSDMB mRNA expression was identified as an independent protective prognostic factor for BLCA, and it was associated with immune cell infiltration, TMB, TME score, and drug sensitivity. CONCLUSIONS: Elevated mRNA expression of GSDMB has a causal link to a higher risk of BLCA and the likelihood of bladder surgery, but also indicates a better prognosis. Thus, GSDMB exhibits dual effects and might serve as a potential biomarker for predicting onset and progression of BLCA. Nevertheless, further investigation of pathogenesis and mechanisms underlying GSDMB is warranted.

Bladder cancer (BLCA)↗

PubMed2026

A cuproptosis-related lncRNAs-based risk signature for predicting prognosis and immune status in glioma.

BACKGROUND: Glioma is one of the most prevalent primary malignant brain tumors, characterized by poor prognosis and limited treatment options. Recent studies have identified cuproptosis, a novel copper-dependent form of regulated cell death, as a critical mechanism involved in tumor progression. However, the role of cuproptosis-related long non-coding RNAs (lncRNAs) in glioma remains not fully clarified. This study aimed to develop and validate a prognostic model based on cuproptosis-associated lncRNAs to predict patient outcomes and guide individualizing therapeutic strategies. METHODS: Transcriptomic profiles and clinical data were obtained from The Cancer Genome Atlas (TCGA), The Genotype-Tissue Expression (GTEx), and the Chinese Glioma Genome Atlas (CGGA) databases. Cuproptosis -related prognostic lncRNAs were filtered via univariate and multivariate Cox and Least absolute shrinkage and selection operator (LASSO) regression analyses, which were selected to establish a prognostic model for glioma. Samples were divided into high- and low-risk groups, and the predictive performance of the prognostic model was evaluated based on receiver operating characteristic (ROC) curves, Kaplan-Meier (K-M) survival curves, and a nomogram. In addition, immune cell infiltration, tumor mutational burden (TMB), immunophenoscore (IPS), Tumor Immune Dysfunction and Exclusion (TIDE) and drug sensitivity were analyzed. Expression levels of selected lncRNAs and proteins were validated using quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) and Western blotting. RESULTS: An 11-lncRNA signature associated with cuproptosis was established, and the risk score derived from this model was identified as an independent prognostic factor for glioma. The model exhibited excellent predictive ability, with area under the curve (AUC) values of 0.880, 0.913, and 0.866 for 1-, 3-, and 5-year survival, respectively. Higher TMB, immune checkpoint expression, and IPS were observed in the high-risk group and no significant difference was observed in TIDE between risk groups. Drug sensitivity analysis identified TPCA-1, KIN001-135, and ispinesib mesylate as potential therapeutic agents. Expression validation in glioma cells further supported the biological relevance of the selected lncRNAs. CONCLUSIONS: This cuproptosis-related lncRNA-based signature demonstrates strong prognostic value and may serve as a promising tool for glioma risk stratification and personalized treatment selection.

Glioma↗

PubMed2026

A machine learning-derived intratumoral heterogeneity-related signature predicts the prognosis for and therapeutic response in patients with skin cutaneous melanoma.

BACKGROUND: Reliable biomarkers for predicting prognosis and therapeutic response in skin cutaneous melanoma (SKCM) remain limited. This study aimed to develop an intratumoral heterogeneity (ITH)-related prognostic signature for SKCM using integrative machine learning. METHODS: RNA sequencing (RNA-seq) data from 472 SKCM patients in The Cancer Genome Atlas (TCGA) and 214 patients in the GSE65904 cohort were analyzed. ITH scores were calculated using the DEPTH2 algorithm. Differentially expressed genes (DEGs) were identified between high- and low-ITH groups [|log2fold change (FC)| ≥1, false discovery rate (FDR) <0.05]. Based on 38 prognostic DEGs identified by univariate Cox regression, we employed an integrative framework of 101 machine learning algorithm combinations to construct prognostic models in the TCGA training cohort. The model with the highest average concordance index (C-index) was validated in the GSE65904 cohort and selected as the prognostic ITH-related signature (PIRS). Associations of the PIRS risk score with tumor mutational burden (TMB), immune cell infiltration, immune checkpoint gene expression, and drug sensitivity were systematically evaluated. Model performance was assessed using receiver operating characteristic (ROC) curves and Cox regression analyses. RESULTS: A 38-gene PIRS was constructed using the plsRcox algorithm. Patients with high PIRS risk scores exhibited significantly poorer overall survival (OS) in both the TCGA and Gene Expression Omnibus (GEO) cohorts. The PIRS was identified as an independent prognostic factor, with area under the curve (AUC) values of 0.779, 0.734, and 0.756 for 1-, 3-, and 5-year survival, respectively. High-risk samples displayed significantly lower TMB (P<0.05), reduced immune and stromal cell infiltration (P<0.001), downregulated immune function, and decreased expression of immune checkpoint genes. Additionally, high- and low-PIRS risk score groups exhibited distinct sensitivity patterns to different classes of targeted agents. CONCLUSIONS: The machine learning-derived PIRS robustly predicts prognosis in SKCM patients. Its clinical application is promising for optimizing patient risk stratification and treatment decisions, though further prospective validation is warranted.

Skin cutaneous melanoma (SKCM)↗

PubMed1985

Transneuronal transport of wheatgerm agglutinin conjugated with horseradish peroxidase in the somatosensory system of the rat: a light- and electron-microscopic study.

Experiments were performed in order to investigate, at the light- and electron-microscopic levels, the transneuronal transport of wheatgerm agglutinin conjugated with horseradish peroxidase (WGA:HRP) in the somatosensory system of rats. In five adult albino rats, various amounts of WGA:HRP at different concentrations were bilaterally injected in the dorsal column nuclei (DCN). In one additional animal, WGA:HRP was injected in one side, whereas free HRP was injected in the contralateral DCN. In another five rats, WGA:HRP was injected in the first somatosensory cortex (SI). The postinjection survival time of the animals ranged from 30 to 48 hr. The histochemical visualization of the enzyme was performed using either paraphenylenediamine-pyrocatechol (PPD-PC) or tetraethylbenzidine (TMB) as chromogens on adjacent horizontal serial sections. All the reacted samples were studied at the light-microscopic level, and sections from four animals were processed for the ultrastructural investigation. After DCN injections, a massive anterograde labeling was always observed in nucleus ventralis posterolateralis (VPL) of the thalamus, where also labeled neurons and glial cells were detected at both the light- and the electron-microscopic levels. Labeled neurons and terminals in the lateral border of nucleus reticularis (Re) of the thalamus were also observed after either DCN or SI injection of WGA:HRP. Our results show that WGA:HRP is effectively transported not only anterogradely and retrogradely through the somatosensory system of the rat, but also transneuronally. The transneuronal transfer of the tracer seems to be mainly related to the postlabeling survival time of the animal, and it does not occur when free HRP is injected. In controlled experimental conditions, WGA:HRP can therefore be useful for tracing secondary projections. Moreover, in the present report, the existence of a mediolateral arrangement of the projections of the somatosensory-related area of Re toward VPL is directly demonstrated. As for the histochemical procedure employed, differences in sensitivity are shown between PPD-PC and TMB, although the same general pattern of labeling is present with both chromogens.

Afferent Pathways↗

PubMed1996

Effects of sulfhydryl reagents on the regulation of cytosolic pH in rat sublingual acini.

The effects of sulfhydryl (SH) reagents on the regulation of cytosolic pH (pHi) in rat sublingual mucous acini were examined using pH-sensitive dye 2',7'-biscarboxyethyl-5(6)-carboxyfluorescein (BCECF). The membrane permeable SH reagent N-ethylmaleimide (NEM) resulted in a cytosolic acidification (0.19 +/- 0.02 pH unit after 5-min treatment). In contrast, the impermeable SH reagents 5,5'-dithiobis(2-nitrobenzoic acid) (DTNB), p-chloromercuribenzoic acid (PCMB) and Cu2+ did not affect the resting pHi. Muscarinic stimulation with carbachol (CCh) induced a cytosolic acidification (0.15 +/- 0.01 pH unit after 5 min). Cu2+ enhanced the CCh-stimulated acidification 2-fold (0.30 +/- 0.02 pH unit after 5 min). Preincubation with SH reducing agent dithiothreitol (DTT) prevented the NEM-induced and Cu2+ -enhanced pHi decreases. The Cu2+ -enhanced but not the NEM-induced acidifications were reversed by addition of DTT after stimulation. Na+/H+ exchange was not influenced by Cu2+ or NEM, suggesting that the SH reagent-induced acidification is not caused by inhibition of exchanger activity. Anion channel inhibitor diphenylamine-2-carboxylate (DPC) abolished the NEM-induced and the Cu2+ -enhanced acidifications, suggesting that the acidification was mediated by HCO3- efflux via anion channels. Cu2+ did not affect the CCh-evoked increase in cytosolic free Ca2+ concentration ([Ca2+]i). In contrast, NEM triggered an elevation in [Ca2+]i, and DTT completely prevented this increase. The CCH-stimulated [Ca2+]i increases were prevented by blocking Ca2+ release from the intracellular pool with 8-(diethylamino)-octyl-3,4,5-trimethoxybenzoate (TMB-8), and the NEM-stimulated [Ca2+]i increases were abolished by chelating cytosolic Ca2+ with bis-(o-aminophenoxy)-ethane-N,N,N',N'-tetraacetic acid (BAPTA). TMB-8 prevented the CCh-stimulated, but not the Cu2+ -enhanced pHi decrease, and the NEM-induced pHi decrease was not blocked by BAPTA, suggesting that the effects of Cu2+ and NEM on anion channels are independent of Ca2+. Taken together, these results indicate that SH groups play a critical role in pHi regulation and the reactive SH groups are probably located on cytoplasmic site(s) of anion channels or an associated regulatory protein.

Animals↗

PubMed2026

Long-Term Outcomes and Paired Immune and Genomic Exploratory Analyses After Neoadjuvant Dose-Dense MVAC in Muscle-Invasive Bladder Cancer: A Single-Centre Case Series.

Background/Objectives: Cisplatin-based neoadjuvant chemotherapy (NAC) followed by radical cystectomy has been the standard of care for muscle-invasive bladder cancer (MIBC) for two decades, yet a substantial proportion of patients derive no benefit. As antibody-drug conjugates and immune checkpoint inhibitors reshape perioperative treatment, it is unclear which patients retain meaningful benefit from platinum. We describe long-term outcomes and exploratory paired immune and genomic analyses in a single-centre cohort treated with dose-dense MVAC (dd-MVAC). Methods: We retrospectively identified 54 consecutive patients with MIBC treated with neoadjuvant dd-MVAC between November 2013 and November 2019. Forty-two underwent radical cystectomy and are assessable for pathologic response. Immunohistochemistry for CD3, CD8, FOXP3, PD-1, PD-L1, PD-L2, and NY-ESO-1 was evaluable in 31 baseline specimens and 22 paired specimens; paired genomic profiling was evaluable in 12 cases, with paired tumour mutational burden (TMB) in 10 by whole-exome sequencing and 7 by TSO-500. Paired analyses necessarily exclude patients achieving a pathologic complete response (pCR), who have no residual tumour, and most early progressors. Results: pCR was achieved in 11/42 operated patients (26%, 95% CI 15-41). Median follow-up was 87 months (IQR 24-104). Hydronephrosis was the only baseline factor associated with absence of pCR (p = 0.016). Within the operated cohort, pCR was associated with longer recurrence-free survival (log-rank p = 0.017), but the difference in overall survival did not reach significance (p = 0.121). NAC reduced intratumoral FOXP3 (q = 0.001), NY-ESO-1 (q = 0.013), PD-L2 (q = 0.013), and CD3 (q = 0.043) after correction for multiple comparisons, whereas TMB showed no significant change (TSO-500 p = 0.67; WES p = 0.86). No statistically significant association was detected between any baseline immune marker, including PD-L1, and pCR. The mutational landscape was largely concordant before and after NAC. Conclusions: This study was exploratory and was not powered to validate predictive biomarkers. In this long-term cohort, dd-MVAC was associated with measurable depletion of intratumoral immune populations in chemoresistant tumours, while paired genomic profiles remained broadly concordant. No pre-treatment biomarker identified platinum-refractory patients, but the small evaluable subsets mean these are hypothesis-generating rather than negative findings, and prospective studies with pre-specified biomarker endpoints are required.

chemoresistance↗

PubMed2025

A comparative genomic analysis of left- and right-sided colon cancer using real-world data from the AACR project GENIE BPC dataset.

Left- and Right-sided colon cancers (LCC and RCC) are increasingly recognized as distinct clinicopathological and molecular subtypes with divergent prognoses and therapeutic responses. Leveraging a large, multi-institutional cohort from the AACR Project Genomics Evidence Neoplasia Information Exchange (GENIE) Biopharma Collaborative (BPC) (n = 750; LCC: 363 vs. RCC: 387), we conducted a comprehensive analysis of mutational profiles, tumor mutation burden (TMB), and survival outcomes. Our findings revealed a markedly higher TMB in RCC compared to LCC (6.65 ± 11.3 vs. 3.17 ± 4.35; adjusted P = 3.12×10-32), suggesting greater genomic instability in RCC. After applying functional annotation filters (PolyPhen > 0.85, SIFT < 0.05), RCC tumors were significantly enriched for mutations in BRAF (23.1% vs. 6.7%), KMT2D (8.6% vs. 3.2%), and SMAD4 (13.1% vs. 7.3%), while TP53 mutations predominated in LCC (40.6% vs. 31.8%). Multivariate Cox regression analysis identified RCC as an independent predictor of poorer overall survival (OS) relative to LCC (HR: 1.30, 95% CI: 1.02-1.66, P = 0.033). Notably, KRAS mutations were associated with significantly worse OS in LCC (HR: 1.68, 95% CI: 1.06-2.70, P = 0.027), while BRAF mutations predicted adverse outcomes in RCC (HR: 1.58, 95% CI: 1.05-2.37, P = 0.028). These results underscore the prognostic value of tumor sidedness and specific genetic alterations in colon adenocarcinoma. Our study highlights the need for sidedness-specific molecular profiling to inform precision oncology strategies in colon cancer management.

BRAF↗

PubMed1976

[Effect of arpenal on the EMG-potentials of the anterior tibial muscle in cats during acute phosdrine poisoning].

The authors examined the changes in the nerve-muscular conductivit occuring after acute poisoning with phosdrine and treatment with arpenal and oximic reacytivators of HE-toxogonine and TMB-4 on 20 cats, anesthethised with urethane and atropine protection under the conditions of artificinal respiration. They found that there was a total nerve-muscular block cessation of the mediation in the myoneural synaptic zones, characterized by complete cessation also of the induced electrical responses after single and serial stimuli, during acute intoxications with phosdrine, used in lethal doses of 300 mg/kg intramuscularly. After treatment with H-cholinolitics (arpenal) there was a quick recovery of the muscle contractions as well as of the evoked myopotentials after stimulation with single electric stimuli. In contrast to the oximnic reactivators of He (toxogonine, TMB-4) during serial electric stimuli (10,20 and 30 per second after treatment with arpenal there was a quick contraction only after the first stimulus, after which a progresive weakening of the induced electric myopotentials followed till the appearence of a total nerve-muscular block. This phenomenon was explained by the lack of reactivating properties of H-cholinolitics to HE, inhibited by FOV.

Acute Disease↗

PubMed1999

The effect of luminol on presumptive tests and DNA analysis using the polymerase chain reaction.

This study was designed to test the following factors involved with processing luminol treated bloodstained evidence: 1) The reactivity of other presumptive chemical color tests, phenolphthalin (PT) and tetramethylbenzidine (TMB), following the application of the light emitting luminol presumptive test. 2) The effect of different cleanings of various bloody substrates on the luminol test. 3) The effect of different cleanings of various bloody substrates on the ability to obtain DNA suitable for PCR testing. 4) The ability to extract DNA from luminol treated bloodstained substrates using three extraction techniques. 5) The effect of spraying washed and unwashed bloodstains on various substrates with luminol on the ability to correctly type the DNA using PCR. Our findings indicated that luminol did not adversely effect the PCR testing and did not interfere with the PT and TMB presumptive tests for blood. It was determined that the substrate and the method of cleaning were the major factors affecting DNA yield and the ability to type the bloodstains using PCR based technologies.

Benzidines↗

PubMedDate not supplied

[A sensitive method for quantitative analysis of hydrogen peroxide and oxidase substrates in biological samples].

The sensitive method for peroxidative assays of hydrogen peroxide (up to 5 nmole in 1 ml) and oxidases' substrates (glucose, ethanol) has been developed by use of a non-cancerogenic chromogen--3,3', 5,5'-tetramethylbenzidine (TMB), horseradish peroxidase and corresponding oxidases. The proposed modification of the known method consists in using decreased concentration of TMB (0.05-0.1 mM) and stopping the reaction by adding of acid to pH 1.4-2.1. This approach allowed to enhance the sensitivity of assays of corresponding analytes (7-10 times) and decrease the costs of analysis.

Benzidines↗

PubMedDate not supplied

[State of energy metabolism and microsomal monooxygenases in animals exposed to inhaled 1,2,4-trimethylbenzene].

The investigations demonstrate that unfavourable changes occur in the tissues and red blood cells of the animals exposed to a single dose of 1,2,4-trimethylbenzene (TMB) in a concentration of 10 mg/m3; moreover, the inclusion of 32P is increased in the biochemical structures of the animals and the concentrations of Na, K, Mg, and Ca ions change. Exposure to TMB, 0.01-1.0 mg/m3 causes profound changes in the animals. Microsomal monooxygenases were found to activate in the lung, liver, and kidney of the animals exposed to TB in concentrations of 10 and 1 mg/m3.

Adenosine Triphosphatases↗

PubMed2001

[Specific nature of the software used to construct simulations: physiologically-based toxicokinetic models].

Building of the physiologically-based toxicokinetic (PBTK) models is based on the application of simulation languages, such as advanced continuous simulation language (ACSL). The aim of this study was to develop the principles of constructing the fundamental model and the models dedicated to chemicals found in the work environment (e.g. trimethylbenzene (TMB) isomers present in the petrochemical, paint and lacquer and related industries). The fundamental model is based on four main compartments (fat tissues, richly perfused tissue, slowly perfused tissue and liver) and six auxiliary compartments (lungs, venous blood, arterial blood, body weight, inhaled air and exhaled air). The basic element of the PBTK model comprises blocks containing definitions of variables and constants supplemented by the following parameters: command, calculated, transferred and resulted. The models dedicated to various chemicals and organisms are built by a suitable modification of the fundamental model. All sets of command parameters values for the organism, chemical and simulation are written in the text files and loaded before or during the simulation. The empirical data obtained in experiments with volunteers are used in a similar way. The specimen dedicated model was built for 1,2,3-TMB (hemimellitene). 2,3-Dimethylbenzoic acid (2,3,-DMBA) (a hemimelitene metabolite) excretion rate data obtained from an experiment during which volunteers were exposed to hemimellitene at 25 at 100 mg/m3 were compared with the results of the computer simulation. A high convergence of the comparable values was obtained. Simulations were also made for exposure periods of one week and one month. The results confirmed the experiment-based recommendations on the assessment of the occupational exposure. The application of the new physiologically-based toxicokinetic models renders it possible to forecast toxic chemical (or it metabolite) concentrations corresponding to the concentrations of those chemicals in the workplace atmosphere.

Body Fluid Compartments↗

PubMedDate not supplied

[Inhibition of peroxidase oxidation of aromatic amines by substituted phenols].

Peroxidase-catalyzed oxidation of o-phenylene diamine (OPD) was competitively inhibited by trimethylhydroquinone (TMHQ), 4-tert-butylpyrocatechol (In5), and 4,6-di-tert-butyl-3-sulfanyl-1,2-dihydroxybenzene (In6). In6 was the most efficient inhibitor (Ki = 11 microM at 20 degrees C in 0.015 M phosphate-citrate buffer, pH 6.0). The effects of In5 and In6 were not preceded by periods of induction of OPD oxidation products (contrary to TMHQ). Peroxidase-catalyzed oxidation of tetramethylbenzidine (TMB) was non-competitively inhibited by In6 and 3-(2-hydroxyethylthio)-4,6-di-tert-butylpyrocatechol (In4), whereas o-aminophenol (OAP) acted as a mixed-type inhibitor. The effects of all three inhibitors were preceded by an induction period, during which TMB oxidation products were formed. Again, In6 was the most efficient inhibitor (Ki = 16 microM at 20 degrees C in 0.015 M phosphate-citrate buffer supplemented with 5% ethanol, pH 6.0). Judging by the characteristics of the inhibitors, taken in aggregate, it is advisable to use the pairs OPD-In5 and OPD-In6 in systems for testing the total antioxidant activity of biological fluids of humans.

Amines↗

PubMed1992

[The development of an enzyme immunoassay for the detection of the herbicide metolachlor in water samples].

Since December 1990, strict limits for pesticide content in drinking water have been in effect in the FRG. These limits have to be enforced and controlled regularly. Because the classical analytical methods, like GC/MS and HPLC are relatively expensive and complicated, concentration and clean up of the samples are necessary. Therefore, the significance of Enzyme Immunosorbent Assays has increased in environmental analysis. The topics of our research are synthesis of suitable Metolachlor conjugates for immunization and as coating antigen, as well as development of an Enzyme Immunosorbent Assay. The chloroacetanilide Metolachlor was coupled with an AMSA-Spacer on Sheep IgG and with AHT-Spacer on BSA. The epitope density was measured photometrically with TNB-derivate. Polyclonal antibodies were produced in white New Zealand rabbits. Metolachlor-AMSA-Sheep IgG conjugate was served as immunogen. The test is indirect and competitive. Microtiter plates are coated with the coating antigen (Metolachlor-AHT-BSA conjugate). In the next step the Metolachlor sample competes with the coating antigen for the antibodies. Detection of bounded antibodies is indirect with a peroxidase-labelled secondary antibody. The chromogenic substrates ABTS, TMB and OPD were tested. TMB showed the best qualities, fast turnover, as well as good and steady colour. Titer of serum and crossreactivity of other chloroacetanilide pesticides and their metabolites were tested. With the exception of Alachlor and Dimethachlor, no pesticide showed a high interaction with serum. Quantitative interpretation was done with the logit/log transformation, which allows comparison of different sera and test series. The antibodies are specific but the affinity is not good enough to detect the limits assigned by the "deutsche Trinkwasserverordnung". Raising the concentration, as is done in classical analytical methods, would solve the problems so that the test can be used as a screening test.

Acetamides↗

PubMed2004

A yoga-based exercise program for people with chronic poststroke hemiparesis.

BACKGROUND AND PURPOSE: This was a preliminary investigation of the effects of a yoga-based exercise program on people with chronic (greater than 9 months) poststroke hemiparesis. Many people who have had a stroke report an impaired health status because of a reduced level of activity. Proponents of yoga contend that it offers a gentle alternative exercise program that can be easily adapted for people who have had a stroke. SUBJECTS AND METHODS: Four subjects with chronic poststroke hemiparesis participated in this single-case study. The primary outcome measures were the Berg Balance Scale (BBS) and the Timed Movement Battery (TMB). A secondary outcome measure was the Stroke Impact Scale (SIS). The baseline testing phase varied for each subject and ranged from 4 to 7 weeks. The 8-week intervention phase consisted of 1.5-hour yoga sessions, 2 times per week, in the subject's home. The primary outcome data were collected each week, and the secondary outcome data were collected before the baseline testing phase and before and after the intervention phase. RESULTS: Subjects 1, 2, and 4 had improved TMB scores, and subjects 3 and 4 had improved BBS scores. DISCUSSION AND CONCLUSION: The results suggest that yoga may be beneficial to people who have had a stroke. Further investigation is warranted to further examine the effects of yoga in this population.

Aged↗

PubMed1992

Platelet-activating factor-stimulated protein tyrosine phosphorylation and eicosanoid synthesis in rat Kupffer cells. Evidence for calcium-dependent and protein kinase C-dependent and -independent pathways.

The lipid mediator platelet-activating factor (1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine, AGEPC) has been shown to elicit several important biochemical signaling responses in mammalian cells, including polyphosphoinositide hydrolysis, arachidonic acid release/eicosanoid production, and protein tyrosine phosphorylation. In the present study, the roles of Ca2+ and protein kinase C (PKC), two signaling components of the phospholipase C pathway, in AGEPC-stimulated eicosanoid production and protein tyrosine phosphorylation, were investigated in cultured rat Kupffer cells. AGEPC at nanomolar concentrations induced an increase in intracellular calcium concentration ([Ca2+]i), stimulated membrane PKC activity, and resulted in protein tyrosine phosphorylation. The maximal increase in [Ca2+]i and membrane PKC activity in response to AGEPC were observed within 30-50 s, whereas the AGEPC-induced protein tyrosine phosphorylation reached maximal levels within 2-5 min. [Ethylenebis(oxyethylenenitrilo)]tetraacetic acid (EGTA) but not 8-(N,N-diethylamino)-octyl-3,4,5-trimethoxybenzoate hydrochloride (TMB-8), an inhibitor of calcium release from intracellular compartments, nearly abolished the AGEPC-induced increase in [Ca2+]i suggesting involvement of extracellular calcium influx in this event. Both EGTA and TMB-8 abolished or inhibited AGEPC-stimulated protein tyrosine phosphorylation and eicosanoid formation, respectively. The calcium ionophore A23187 alone stimulated eicosanoid production and protein tyrosine phosphorylation with an identical pattern to that of AGEPC. Phorbol myristate acetate (PMA), an activator of PKC, which did not affect [Ca2+]i, mimicked the actions of AGEPC, stimulating eicosanoid production and promoting tyrosine phosphorylation of a set of proteins similar to those phosphorylated following AGEPC stimulation. AGEPC-enhanced tyrosine phosphorylation of some of the protein substrates and eicosanoid production were inhibited in cells "down-regulated" for PKC. Furthermore, both PMA- and AGEPC-stimulated eicosanoid production and protein tyrosine phosphorylation were attenuated or abolished by at least one of the PKC inhibitors, staurosporine, and calphostin C. Taken together, these results are consistent with the conclusions that: (a) AGEPC stimulates the phospholipase-mediated arachidonic acid release/eicosanoid synthesis cascade and protein tyrosine phosphorylation through extracellular Ca(2+)-dependent and PKC-dependent and -independent mechanism(s) and (b) the Ca(2+)-PKC interaction determines the efficacy of the AGEPC-stimulated cellular events.

Animals↗