Disrupted nuclear import of cell cycle proteins in Huntington's/PolyQ disease causes neurodevelopment defects in cellular and Drosophila model

Huntington's disease is caused by an expansion of CAG repeats in exon 1 of the huntingtin gene encoding an extended PolyQ tract within the Huntingtin protein (mHtt). This expansion results in selective degeneration of striatal medium spiny projection neurons in the basal ganglia. The mutation causes abnormalities during neurodevelopment in human and mouse models. Here, we report that mHtt/PolyQ aggregates inhibit the cell cycle in the Drosophila brain during development. PolyQ aggregates disrupt the nuclear pore complexes of the cells preventing the translocation of cell cycle proteins such as Cyclin E, E2F and PCNA from cytoplasm to the nucleus, thus affecting cell cycle progression. PolyQ aggregates also disrupt the nuclear pore complex and nuclear import in mHtt expressing mammalian CAD neurons. PolyQ toxicity and cell cycle defects can be restored by enhancing RanGAP-mediated nuclear import, suggesting a potential therapeutic approach for this disease.

A Case of Vertigo with TORP in Inner Ear

This is a case of a patient with history of ear surgery who visited ENT outdoor, for continuous vertigo which used to get aggravated with loud noise, associated with hearing loss, persistent sensations of right-sided aural fullness/pressure and otalgia for last 2 years. He had history of tympanoplasty with ossiculoplasty using a TORP. On exploration under local anesthesia there was a displaced prosthesis into inner ear, upon removal of which symptoms and severity subsided exponentially.

Nucleoporins are degraded via upregulation of ESCRT-III/Vps4 complex in Drosophila models of C9-ALS/FTD

Disruption of the nuclear pore complex (NPC) and nucleocytoplasmic transport (NCT) have been implicated in the pathogenesis of neurodegenerative diseases. A GGGGCC hexanucleotide repeat expansion (HRE) in an intron of the C9orf72 gene is the most common genetic cause of amyotrophic lateral sclerosis and frontotemporal dementia, but the mechanism by which the HRE disrupts NCT is incompletely understood. We find that expression of GGGGCC repeats in Drosophila neurons induces proteasome-mediated degradation of select nucleoporins of the NPC. This process requires the Vps4 ATPase and the endosomal-sorting complex required for transport complex-III (ESCRT-III), as knockdown of ESCRT-III/Vps4 genes rescues nucleoporin levels, normalizes NCT, and suppresses GGGGCC-mediated neurodegeneration. GGGGCC expression upregulates nuclear ESCRT-III/Vps4 expression, and expansion microscopy demonstrates that the nucleoporins are translocated into the cytoplasm before undergoing proteasome-mediated degradation. These findings demonstrate a mechanism for nucleoporin degradation and NPC dysfunction in neurodegenerative disease.

Bronco T (Shirisadi kasaya), a polyherbal formulation prevents LPS induced septicemia in rats

OBJECTIVE

Here, Bronco T (BT), a polyherbal formulation developed in 1984 for treating asthma, has been repurposed against septicemia-induced ALI.

MATERIALS AND METHODS

Lipopolysaccharides (3 mg/kg BW) were injected intraperitoneally before 24 hours of surgery to assess the cardiorespiratory parameters, blood PaO2/FiO2 and MPO, pulmonary water content and histological changes in the lungs. The pentoxifylline (PTX) (25 mg/kg BW) was used as the positive control and given one hour before LPS. BT was given 3 hours (orally at different doses of 3, 1.5 and 0.75 g/kg BW) before LPS.

RESULTS

The LPS treated group showed significant bradypnea, hypotension and bradycardia, through elongated peaks (RR) and (MAP) respectively and finally death after 95 minutes of LPS injection. The PTX and BT (3 g/kg BW) pretreatment significantly prevented these changes (dose-dependent in the BT group). The survival in these groups was maintained up to 190 min after LPS. The Pentoxifylline showed a better response (75%) than Bronco T (72%). In both the treatments, a significant decrease in pulmonary water content and minimal neutrophil infiltration and intact alveoli-capillary membrane was seen in the transverse section (T.S) of the lungs.

CONCLUSIONS

Significant improvement was noted in survival time with lesser tissue damage and improved pulmonary function was observed by pre-treating with Bronco T in LPS induced septicemia.

Multi-omic analysis of selectively vulnerable motor neuron subtypes implicates altered lipid metabolism in ALS

Amyotrophic lateral sclerosis (ALS) is a devastating disorder in which motor neurons degenerate, the causes of which remain unclear. In particular, the basis for selective vulnerability of spinal motor neurons (sMNs) and resistance of ocular motor neurons to degeneration in ALS has yet to be elucidated. Here, we applied comparative multi-omics analysis of human induced pluripotent stem cell-derived sMNs and ocular motor neurons to identify shared metabolic perturbations in inherited and sporadic ALS sMNs, revealing dysregulation in lipid metabolism and its related genes. Targeted metabolomics studies confirmed such findings in sMNs of 17 ALS (SOD1, C9ORF72, TDP43 (TARDBP) and sporadic) human induced pluripotent stem cell lines, identifying elevated levels of arachidonic acid. Pharmacological reduction of arachidonic acid levels was sufficient to reverse ALS-related phenotypes in both human sMNs and in vivo in Drosophila and SOD1G93A mouse models. Collectively, these findings pinpoint a catalytic step of lipid metabolism as a potential therapeutic target for ALS.

Molecular ecological perspective of methanogenic archaeal community in rice agroecosystem

Methane leads to global warming owing to its warming potential higher than carbon dioxide (CO₂). Rice fields represent the major source of methane (CH₄) emission as the recent estimates range from 34 to 112 Tg CH₄ per year. Biogenic methane is produced by anaerobic methanogenic archaea. Advances in high-throughput sequencing technologies and isolation methodologies enabled investigators to decipher methanogens to be unexpectedly diverse in phylogeny and ecology. Exploring the link between biogeochemical methane cycling and methanogen community dynamics can, therefore, provide a more effective mechanistic understanding of CH₄ emission from rice fields. In this review, we summarize the current knowledge on the diversity and activity of methanogens, factors controlling their ecology, possible interactions between rice plants and methanogens, and their potential involvement in the source relationship of greenhouse gas emissions from rice fields.

Biofiltration of xylene using wood charcoal as the biofilter media under transient and high loading conditions

The main objective of this study was to evaluate the performance of wood charcoal as biofilter media under transient and high loading condition. Biofiltration of xylene was investigated for 150days in a laboratory scale unit packed with wood charcoal and inoculated with mixed microbial culture at the xylene loading rates ranged from 12 to 553gm^-3h^-1. The kinetic analysis of the xylene revealed absence of substrate inhibition and possibility of achieving higher elimination under optimum condition. The pH, temperature, pressure drop and CO₂ production rate were regularly monitored during the experiments. Throughout experimental period, the removal efficiency (RE) was found to be in the range of 65-98.7% and the maximum elimination capacity (EC) was 405.7gm^-3h^-1. Molecular characterization results show Bacillus sp. as dominating microbial group in the biofilm.

Effects of gamma radiation on the early developmental stages of Zebrafish (Danio rerio)

The zebrafish is gaining importance as a popular vertebrate model organism and is widely employed in ecotoxicological studies, especially for the biomonitoring of pollution in water bodies. There is limited data on the genetic mechanisms governing the adverse health effects in regards to an early developmental exposure to gamma radiation. In the present study zebrafish (Danio rerio) embryos were exposed to 1, 2.5, 5, 7.5 and 10Gy of gamma radiation at 3h post fertilization (hpf). Different developmental toxicity endpoints were investigated. Further, expression of genes associated with the development and DNA damage i.e. (sox2 sox19a and p53) were evaluated using Quantitative PCR (qPCR). The significant changes in the expression of sox2 sox19a and p53 genes were observed. This data was supported the developmental defects observed in the zebrafish embryo exposed to gamma radiation such as i.e. increased DNA damage, decreased hatching rate, increase in median hatching time, decreased body length, increased mortality rate, increased morphological deformities. Further, study shows that the potential ecotoxicological threat of gamma radiation on the early developmental stages of zebrafish. Further, it revealed that the above parameters can be used as predictive biomarkers of gamma radiation exposure.

Design and characterization of microstrip based E-field sensor for GSM and UMTS frequency bands

An Electric (E-) field sensor based on coplanar waveguide-fed microstrip antenna to measure E-field strength for dual-band operation at 914 MHz and 2.1 GHz is proposed, designed, and characterized. The parametric optimization of the design has been performed to obtain resonance at global system for mobile communication and universal mobile telecommunication system frequency band. Low return loss (-17 dB and -19 dB), appropriate gain (0.50 dB and 1.55 dB), and isotropic behaviour (directivity ∼ 1 dB), respectively, at 914 MHz and 2.1 GHz, are obtained for probing application. Antenna factor (AF) is used as an important parameter to characterize the performance of the E-field sensor. The AF measurement is explained in detail and results are reported. Finally, using the designed E-field sensor, the E-field strength measurements are carried out in a transverse electromagnetic cell. The key sources of uncertainties in the measurement are identified, evaluated, and incorporated into the final results. The measurement results are compared with theoretical values, which are found in good agreement. For comparative validation, the results are evaluated with reference to an already calibrated commercially available isotropic probe.

Tributyltin chloride (TBTCl)-enhanced exopolysaccharide and siderophore production in an estuarine Alcaligenes faecalis strain

Tributyltin chloride (TBTCl) has been used extensively as an antifouling agent in ship paints, which results in the contamination of aquatic sites. These contaminated sites serve as enrichment areas for TBTCl-resistant bacterial strains. One TBTCl-resistant bacterial strain was isolated from the sediments of Zuari estuary, Goa, India, which is a major hub of various ship-building activities. Based on biochemical characteristics and 16S rDNA sequence analysis, this bacterial strain was identified as Alcaligenes faecalis and designated as strain SD5. It could degrade ≥3 mM TBTCl by using it as a sole carbon source and transform it into the less toxic dibutyltin chloride, which was confirmed by nuclear magnetic resonance and mass spectroscopy. Interestingly, this bacterial strain also showed enhanced exopolysaccharide and siderophore production when cells were exposed to toxic levels of TBTCl, suggesting their involvement in conferring resistance to this antifouling biocide as well as degradative capability respectively.

Enantioselective Tissue Distribution of Ketorolac and its Enantiomers in Rats

The difference in tissue distribution of Ketorolac and its enantiomers were investigated in wistar rats. Separate high performance liquid chromatographic method was developed and validated for determination of Ketorolac and its enantiomers. Oyster BDS (150 × 4.6 mm id., 5 μm particle size) column was used for determination of concentration of Ketorolac. Ketorolac enantiomers were determined using Chiral-AGP column (100 × 4.0 mm I.D., particle size 5 μ, Chrom tech Ltd, Sweden). Detection was done at wavelength of 322 nm using an ultraviolet detector in the analytical system. Ketorolac enantiomers exhibit difference in their disposition in Wistar rats. In kidney, there was a significant difference in pharmacokinetic parameters. The Cmax was nearly 4 times and AUC 0-∞ was found to be more than double for S (-) Ketorolac than that of R (+) Ketorolac. MRT, Ke and t1/2 differ significantly in kidney. In liver, Cmax was found to be approximately 69% higher for S (-) Ketorolac compared to R (+) Ketorolac. AUC 0-∞ did not differ significantly for the enantiomers in liver. In liver, S (-) Ketorolac eliminated very fast in comparison to R (+) Ketorolac having t1/2 (one third) in comparison to R (+) Ketorolac. In lungs, there was no difference observed for Cmax and other parameters but AUC 0-∞ was found to be marginally higher for S (-) ketorolac.

Rhizospheric fungal community structure of a Bt brinjal and a near isogenic variety

AIMS

The objective of this study was to investigate the influence of Cry1Ac gene expressing brinjal (VRBT-8) on the rhizospheric fungal community structure.

METHODS AND RESULTS

qPCR indicated variations in the fungal ITS rRNA copy numbers of non-Bt (1·43-4·43) × 10(9) g(-1) dws and Bt (1·43-3·32) × 10(9) g(-1) dws plots. Phylogenetic analysis of ITS rRNA clones indicated fungal-related group majority of being Ascomycota compared to that of Basidiomycota and Zygomycota in non-Bt- and Bt-planted soils. Sordariomycetes was the dominant class detected in all the stages.

CONCLUSIONS

Despite the variations in the population size and the distribution pattern observed across the non-Bt and Bt brinjal, plant-growth-dependent variability was more prominent compared with genetic modification. Therefore, this study concludes that genetic modification of brinjal crop has minor effect on the fungal community.

SIGNIFICANCE AND IMPACT OF THE STUDY

Brinjal, the important solanaceous crop, is also prone to attack by many insect pests, especially by Leucinoides orbonalis, resulting in significant losses in the crop yield. However, the reports on the effect of transgenic crops and the associated microbial community are inconsistent. The present communication takes into account for the first time the possible interactions between Bt brinjal and the associated fungal community; the latter playing a significant role in maintaining soil fertility. As this study is limited to the structural diversity of fungal community, additional information regarding the functional diversity of the group seems imperative before recommending the commercialization of GM crops.

Rapid and Sensitive Reverse-phase High-performance Liquid Chromatography Method for Estimation of Ketorolac in Pharmaceuticals Using Weighted Regression

A reliable, rapid and sensitive isocratic reverse phase high-performance liquid chromatography method has been developed and validated for assay of ketorolac tromethamine in tablets and ophthalmic dosage forms using diclofenac sodium as an internal standard. An isocratic separation of ketorolac tromethamine was achieved on Oyster BDS (150×4.6 mm i.d., 5 μm particle size) column using mobile phase of methanol:acetonitrile:sodium dihydrogen phosphate (20 mM; pH 5.5) (50:10:40, %v/v) at a flow rate of 1.0 ml/min. The eluents were monitored at 322 nm for ketorolac and at 282 nm for diclofenac sodium with a photodiode array detector. The retention times of ketorolac and diclofenac sodium were found to be 1.9 min and 4.6 min, respectively. Response was a linear function of drug concentration in the range of 0.01-15 μg/ml (R²=0.994; linear regression model using weighing factor 1/x²) with a limit of detection and quantification of 0.002 μg/ml and 0.007 μg/ml, respectively. The % recovery and % relative standard deviation values indicated the method was accurate and precise.

Lead-resistant Providencia alcalifaciens strain 2EA bioprecipitates Pb+2 as lead phosphate

A lead-resistant bacteria isolated from soil contaminated with car battery waste were identified as Providencia alcalifaciens based on biochemical characteristics, FAME profile and 16S rRNA sequencing and designated as strain 2EA. It resists lead nitrate up to 0·0014 mol l(-1) by precipitating soluble lead as insoluble light brown solid. Scanning electron microscopy coupled with energy-dispersive X-ray spectrometric analysis (SEM-EDX) and X-ray diffraction spectroscopy (XRD) revealed extracellular light brown precipitate as lead orthophosphate mineral, that is, Pb(9) (PO(4))(6) catalysed by phosphatase enzyme. This lead-resistant bacterial strain also demonstrated tolerance to high levels of cadmium and mercury along with multiple antibiotic resistance. Providencia alcalifaciens strain 2EA could be used for bioremediation of lead-contaminated environmental sites, as it can efficiently precipitate lead as lead phosphate.

Contamination of ground water as a consequence of land disposal of dye waste mixed sewage effluents: a case study of Panipat district of Haryana, India

Spatial samples of surface and ground water collected from land disposal site of dye waste mixed sewage effluents at Binjhole, in Haryana, India were analyzed to evaluate its effect on quality of pond, hand pumps and ground waters for human health and irrigation purposes. It was found that average COD and TDS of dye houses discharge (310 and 3,920 mg/L) and treated sewage (428 and 1,470 mg/L) on mixing acquired the values of 245 and 1,780 mg/L and only Pb (0.24 microg/L) was above the permissible limit for irrigation purpose. Disposal of this mixed water to village pond changes the COD and TDS to 428 and 1,470 mg/L, respectively. COD and TDS of hand pump water samples were 264 and 1,190 mg/L, where as in tube well water these values were 151 and 900 mg/L. Though the ground water contamination seemed to decrease with the increasing distance from the pond but COD, TDS and BOD values continued to be quite high in water samples drawn from the hand pumps up to a distance of 500 m from pond. However, the major cause of the concern in these waters was Pb (0.11-0.45 ppm). Crops grown with this water shows accumulation of heavy metals like Pb,Cd, Fe, Mn, Ni, Cu, and Zn but in few crops they (Zn, Pb and Cd) exceed the safe limits. Regular consumption of these crop products may lead heavy metal toxicity. It was concluded from this study that the deep seepage of effluents led to deterioration of ground water quality for drinking purposes and the well waters rendered unfit for irrigation purposes within a span of 2 years. This warrants appropriate disposal measures for sewage and dye industry effluents in order to prevent deterioration of ground water and health of human and animals.

True knot in Ryles tube: a case report

Insertion of Ryles tube is a simple routine procedure. During its insertion, minor complications like trauma to nose, nasopharynx and oral cavity do happen from time to time. But as the Ryles tube is usually inserted blindly, potentially life threatening complications like inadvertent entry into trachea, cranial cavity and intravascular penetration have been reported. Folds and kinks may occur, but true knot of the Ryles tube, which we now report, is very rare.

Isolation and characterization of exopolysaccharide produced byVibrio harveyistrain VB23

AIMS

The aim of the study was to isolate and characterize exopolysaccharide (EPS) produced by Vibrio harveyi strain VB23.

METHODS AND RESULTS

Growth and EPS production by V. harveyi strain VB23, was studied in mineral salts medium supplemented with NaCl (1.5%) and glucose (0.2%). The rate of EPS production in batch cultures was highest during the late log phase of growth when compared with stationary growth phase. The exopolymer was recovered from the culture supernatant by using a cold ethanol precipitation-dialysis procedure. Chemical analyses of EPS revealed that it is primarily composed of neutral sugars, uronic acids, proteins and sulfates. The purified EPS revealed prominent functional reactive groups, such as hydroxyl, carboxylic and amides, which correspond to a typical heteropolymeric polysaccharide and the EPS, also possessed good emulsification activity. The gas chromatographic analysis of an alditol acetate-derivatized sample of EPS revealed that it is composed primarily of galactose and glucose. Minor components found were rhamnose, fucose, ribose, arabinose, xylose and mannose.

CONCLUSIONS

The EPS produced by V. harveyi strain VB23 is a heteropolysaccharide possessing good emulsification activity. EPS was readily isolated from culture supernatants, which suggests that the EPS was a slime-like EPS.

SIGNIFICANCE AND IMPACT OF THE STUDY

This is the first report of EPS characterization in luminous V. harveyi bacteria, which describes the isolation and characterization of an EPS expressed by V. harveyi. The results of the study contributes significantly towards an understanding of the chemical composition and applications of the EPS in environmental biotechnology and bioremediation.

Post-irrigation impact of domestic sewage effluent on composition of soils, crops and ground water--a case study

Long-term irrigation with sewage water adds large amounts of carbon, major and micro- nutrients to the soil. We compared the spatial distribution of N, P, K and other micronutrients and toxic elements in the top 0.6 m of an alluvial soil along with their associated effects on the composition of crops and ground waters after about three decades of irrigation with domestic sewage effluent as a function of distance from the disposal point. Use of sewage for irrigation in various proportions improved the organic matter to 1.24-1.78% and fertility status of soils especially down to a distance of 1 km along the disposal channel. Build up in total N was up to 2908 kg ha(-1), available P (58 kg ha(-1)), total P (2115 kg ha(-1)), available K (305 kg ha(-1)) and total K (4712 kg ha(-1)) in surface 0.15 m soil. Vertical distribution of these parameters also varied, with most accumulations occurring in surface 0.3 m. Traces of NO3-N (up to 2.8 mg l(-1)), Pb (up to 0.35 mg l(-1)) and Mn (up to 0.23 mg l(-1)) could also be observed in well waters near the disposal point thus indicating initiation of ground water contamination. However, the contents of heavy metals in crops sampled from the area were below the permissible critical levels. Though the study confirms that the domestic sewage can effectively increase water resource for irrigation but there is a need for continuous monitoring of the concentrations of potentially toxic elements in soil, plants and ground water.

Periampullary carcinoma following biliary ascariasis--a case report

A 42 year old man presented with obstructive jaundice and cholangits. Ultrasonography (USG) revealed dilated intrahepatic biliary radicals and common bile duct (CBD). The bile duct also showed a curvilinear parallel intraluminal structure suggesting biliary ascariasis. The CBD was explored and a dead worm removed but jaundice persisted. Endoscopic retrograde cholangio pancreaticography (ERCP) was done showing a periampullary mass which on biopsy showed a villous adenoma with highly dysplastic changes. A Whipple's pancreaticoduodenectomy was performed and the growth proved to be a well differentiated periampullary adenocarcinoma.

Development of biosensors for the detection of mercury and copper ions

The development of genetically engineered biosensors for copper and mercury ions is described. The biosensors have been constructed by fusing thelux or light emitting genes fromVibrio fischeri with genetic regulating elements that respond to copper ions or mercury ions, derived respectively fromEscherichia coli andSerratia marcescens. The fusions were placed intoE. coli cells which then emitted light in response to copper or mercury ions. Data is presented describing the sensitivity, specificity, and dynamic range of the biosensors to their respective target metal ions. A preliminary description of experiments is provided indicating how these biosensors might be used to investigate the bioavailability of mercury and copper ions in environmental samples.

Influence of chromium on some physiological variables of Anabaena doliolum: interaction with metabolic inhibitors

The impact of 2,4-dinitrophenol and chlorophenyl dimethylurea on ATP content, carbon fixation, O2 evolution, nitrogenase activity and Cr uptake of Anabaena doliolum has been studied. 2,4-Dinitrophenol has been found to be more toxic than chlorophenyldimethylurea for all these processes. However, when Cr toxicity to above variables was assessed in their presence the interaction was less than additive. An initial (10-15 min) concentration-dependent rapid Cr uptake, followed by a slow one, indicates a biphasic uptake. A significant inhibition of Cr uptake in the presence of both these metabolic inhibitors suggests the involvement of metabolic processes in Cr uptake.

Effect of four heavy metals on the biology of Nostoc muscorum

This study presents the effects of Cr, Pb, Ni and Ag on growth, pigments, protein, DNA, RNA, heterocyst frequency, uptake of NH4+ and NO3-, loss of electrolytes (Na+ and K+), nitrate reductase and glutamine synthetase activities of Nostoc muscorum. The statistical tests revealed a direct positive correlation between the metal concentration and inhibition of different processes. Ni was found to be more toxic against growth, pigments and heterocyst differentiation compared to the other metals. Inhibition of pigment showed the following trend: chlorophyll greater than phycocyanin greater than carotenoid. No generalized trend for inhibition of macromolecules was observed. The loss of K+ and Na+ as affected by Cr, Ni and Pb was similar but more pronounced for K+ than Na+. The inhibition of physiological variables depicted the following trend: Na+ loss greater than K+ loss greater than glutamine synthetase greater than NH4+ uptake greater than growth greater than NO3- uptake greater than nitrate reductase greater than heterocyst frequency. This study therefore suggests that loss of electrolytes can be used as a first signal of metal toxicity in cyanobacteria. However, further study is needed to confirm whether the abnormality induced by nickel (branch formation) is a physiological or genetic phenomenon.

Mutagenicity and tumorigenicity of dihydrodiols, diol epoxides, and other derivatives of benzo(f)quinoline and benzo(h)quinoline

The mutagenic activities of benzo[f]quinoline, benzo[h]quinoline, and a number of their derivatives, including dihydrodiols, K-region oxides, diol epoxides, and tetrahydroepoxides, were assessed in strain TA 100 of Salmonella typhimurium. The dihydrodiol derivatives of benzo[f]quinoline and benzo[h]quinoline were also tested for tumorigenic activity in newborn mice. Benzo[f]quinoline was metabolically activated in the presence of rat liver S-9 preparation to products mutagenic to the bacterial system to a greater extent than was benzo[h]quinoline. However, trans-7,8-dihydro-7,8-dihydroxybenzo[f]quinoline was less mutagenic compared to trans-7,8-dihydroxy-7,8-dihydrobenzo[h]quinoline in the presence of rat liver homogenate. The data on the mutagenic activity of the dihydrodiol derivatives of benzoquinolines were consistent with the intrinsic mutagenicity of the corresponding epoxide derivatives, in that the bay-region diol epoxides and tetrahydroepoxide of benzo[h]quinoline exhibited considerably higher mutagenic activities compared to those of the corresponding derivatives of benzo[f]quinoline at equivalent doses. The K-region oxides of benzo[f]quinoline and benzo[h]quinoline were significantly less mutagenic than their corresponding bay-region diol epoxide and tetrahydroepoxide derivatives. The demonstration that benzo[f]quinoline is significantly more mutagenic than trans-7,8-dihydro-7,8-dihydroxybenzo[f]quinoline, a precursor to the weakly mutagenic bay-region diol epoxide, suggests that the bay-region diol epoxide formation is not the principal pathway for the metabolic activation of benzo[f]quinoline to a mutagen. On the other hand, the isomeric benzo[h]quinoline appears to exert its mutagenic effect via the formation of its bay-region diol epoxide. These results indicate that the position of a nitrogen heteroatom in phenanthrene (the analogous carbocyclic aromatic hydrocarbon) not only has a marked effect on the mutagenic activities of the diol epoxide derivatives, but also can alter the metabolic activation pathways of the parent hydrocarbon. Benzo[f]quinoline, benzo[h]quinoline, and their dihydrodiol derivatives were not tumorigenic in newborn mice.

Toxicity of chromium and tin to Anabaena doliolum. Interaction with sulphur-containing amino acids and thiols

Toxicity of chromium and tin on growth, heterocyst differentiation, nitrogenase activity and 14CO2 uptake of Anabaena doliolum and its amelioration by sulphur-containing amino acids and thiols has been studied. The final growth yield was found to be approximately 51% and 58% of control at sublethal concentration of chromium and tin respectively. Among various amino acids tested, cysteine (0.05 mM) significantly restored growth, heterocyst differentiation, nitrogenase and 14CO2 uptake of test alga. Dithiothreitol (1 mM) restored all the parameters and processes better than monothiol, mercaptoethanol. It is obvious from present investigation that sulphur-containing amino acids and thiols, viz. cysteine, methionine, cystine, mercaptoethanol and dithiothreitol, may appreciably alleviate the toxicity of heavy metals in N2-fixing cyanobacteria if present in an aquatic ecosystem.

Hepatic DNA adduct formation in rats treated with benzo[f]quinoline

The formation of hepatic DNA adducts in male Sprague-Dawley rats following i.p. administration of benzo[f]quinoline (BfQ) was examined using a 32P-post-labeling assay. BfQ exhibited a low binding (11-27 amol adducts/microgram DNA) to liver DNA. Two BfQ-nucleoside adducts (one major and one minor) were detected. The BfQ-DNA adducts formed in vivo were chromatographically distinct from the adducts formed by the reaction of calf thymus DNA in vitro with BfQ-5,6-oxide, syn-7 beta,8 alpha-dihydroxy-9 beta,10 beta-epoxy-7,8,9,10-tetrahydroBfQ, anti-9 alpha,10 beta-dihydroxy-7 alpha,8 alpha-epoxy-7,8,9,10-tetrahydroBfQ, or anti-7 beta,8 alpha-dihydroxy-9 alpha,10 alpha-epoxy-7,8,9,10-tetrahydroBfQ-N- oxide. These results suggest that the bay-region diol epoxide of BfQ, unlike the bay-region diol epoxide derivatives of polynuclear aromatic hydrocarbons, is not involved in the covalent binding of BfQ to DNA.

Metabolism of benzo[f]quinoline by rat liver microsomes

The metabolism of [1,3-14C]benzo[f]quinoline (BfQ) by liver microsomes from control, 3-methylcholanthrene (3-MC)-pretreated and phenobarbital (PB)-pretreated rats has been investigated in order to gain insights into the effect of mixed function oxidase inducers on the types and levels of specific metabolites as formed in vitro. The rates of metabolism of BfQ by liver microsomes from control, 3-MC- and PB-pretreated rats were 0.5, 3.6 and 2.4 nmol/min/mg of respectively. The most predominant metabolite of BfQ detected with liver microsomes from 3-MC-pretreated rats was BfQ-7,8-dihydrodiol, a precursor of the bay-region diol epoxide, constituting 41% of the total ethyl acetate-extractable metabolites. Other metabolites obtained along with their relative proportions were as follows: BfQ-N-oxide, 23% 7-hydroxyBfQ, 15%; 9-hydroxyBfQ, 9%; and BfQ-9,10-dihydrodiol, 6%. BfQ-5,6-dihydrodiol, a K-region dihydrodiol, was a trace metabolite representing approximately 1.0% of the total metabolism. Liver microsomes from PB-pretreated rats oxidized BfQ primarily to BfQ-N-oxide and 9-hydroxyBfQ, which constituted 41% and 20% of the total ethyl acetate-extractable metabolites of BfQ. The relative proportions of BfQ-9,10-dihydrodiol, BfQ-7,8-dihydrodiol and 7-hydroxy-BfQ formed were 12%, 3% and 13% respectively, while the figure for BfQ-5,6-dihydrodiol was 0.5%. The profile of metabolites formed by liver microsomes from control rats was similar to that generated by microsomes from PB-pretreated rats. While benzo-ring metabolites represented a major part of the metabolism of BfQ by liver microsomes from either 3-MC- or PB-pretreated rats, these two types of microsomes exhibited a positional selectivity in the oxidation of BfQ, the former primarily attacking the 7,8-position of BfQ while the latter preferentially oxidizing the 9,10-position. The preponderance of the potentially mutagenic BfQ-7,8-dihydrodiol amongst the metabolites generated by liver microsomes from 3-MC-pretreated rats suggests a possible role for cytochrome P-450c, the major form of rat hepatic cytochrome P-450 induced by 3-MC, in the metabolic activation of BfQ.

3, 5-Dibromo-2'-chloro-4'-isothiocyanatosalicylanilide, a potent anthelmintic

The compound, 3, 5-dibromo-2'-chloro-4'-isothiocyanatosalicylanilide, has been tested against various nematode and cestode parasites in experimental and domestic animals. It shoved 100% activity against Ancylostoma ceylanicum, A tubaeformis, Syphacia obvelata, ascaridia galli, Toxocara spp., Toxascaris sp., Gnathostoma spinigerum, Hymenolepis nana, Raillietina spp. and Taenia spp. in doses 25-70 mg/kg given in single or multiple administrations.

Anticestode activity of 3,5-dibromo-2'-chlorosalicylanilide-4'-isothiocyanate--a preliminary report

Many compounds have been claimed to possess powerful taenicidal activity but only a few are able to remove the tapeworms complete with scolices; accordingly better drugs are still needed. A series of 3, 5-dibromosalicylanilides, possessing a molecular framework similar to that of niclosamide (Gönnert and Schraufstätter, 1960) was tested for taenicidal activity; the most potent anticestode compound was found to be 3, 5-dibromo-2' -chlorosalicylanilide-4' -isothiocyanate (CDRI Compound 77–6). The present communication compares the efficacy of Compound 77–6 with niclosamide, N-(2' -chloro-4-nitrophenyl)-5-chlorosalicylamid (Bayer, power with 75% active ingredient) and praziquantel, 2-cyclohexylcarbonyl-1–3, 4, 6, 7, 11 b-hexahydro-2H-Pyrazino [2–1-a], isoquinoline-4-one (Droncit, E. Merck & Bayer, powder, 100% pure) (Seubert et al., 1977) in rats and mice.

Immunogenicity of three C-terminal synthetic peptides of the beta subunit of human chorionic gonadotropin and properties of the antibodies raised against 45-amino acid C-terminal peptide

Immunological studies were carried out in rhesus monkeys and rabbits on three C-terminal synthetic peptides of beta-hCG (115-145; 111-145 and 101-145) after conjugating these to tetanus toxoid (TT). The immunogenicity of the peptide conjugates was comparatively poorer with reference to Pr-beta-hCG-TT conjugates at similar doses and immunization schedule. Amongst the three peptides, the best response was obtained with the 45-amino acid c-terminal peptide (45-CTP; 101-145). The anti-45-CTP recognized native hCG and was devoid of cross-reaction with hLH. hCG-induced testosterone production by mouse Leydig cells was inhibited by anti-45-CTP antiserum, although its neutralization capacity decreased more rapidly upon dilution than anti-beta-hCG sera of comparable titres. Immune complexes formed by the anti-45-CTP with hCG had a lower sedimentation value than those formed by anti-beta-hCG antisera with hCG, suggesting the presence of a limited number of immuno-determinant regions in the 45-amino acid C-terminal synthetic peptide.

Synthesis of substituted 1-hydroxy-2-naphthanilides as potential cestodicidal agents

A series of substituted 1-hydroxy-2-naphthanilides 4--14 has been synthesized by treating 1-hydroxy-2-naphthoic acids 2 with substituted anilines 3. The nitronaphthanilides, on reduction and subsequent treatment with thiophosgene, gave the corresponding substituted 2-naphthanilide isothiocyanates 30--33. Substitution of the chlorine of 8 by various cyclic amines gave 3'-nitro-4'-substituted 1-hydroxy-2-naphthanilides 15--21. Various 3-aryl-4-oxo-2,3-dihydro-1,3-naphthoxazine-2-thiones 34-43 and 3 aryl-2,4-dioxo-2,3-dihydro-1,3-naphthoxazines 44--51 have been prepared by reacting the corresonding naphthanilides with thiophosgene and ethyl chloroformate, respectively. All the compounds were tested for their cestodicidal activity against Hymenolepis nana infection in rats; 30 was found to be the most active compound of the series, showing 100% clearance of infection at a single oral dose of 7.5 mg/kg.

Isoimmunization against human chorionic gonadotropin with conjugates of processed beta-subunit of the hormone and tetanus toxoid

The immunogenicity of the conjugate prepared from "processed" beta-subunit of human chorionic gonadotropin (choriogonadotropin, HCG) and tetanus toxoid has been studied in animals and a human subject. The conjugate elicited the formation of high-affinity (Ka = 10(9)-10(11) M-1) anti-HCG and anti-tetanus antibodies. On primary immunization, the antibody, response lasted for several months. Repeat injection of the conjugate in the declining phase of antibody titers produced a booster response without a lag period. The antibodies reacted with the beta-subunit of HCG and the complete HCG molecule but were devois of significant crossreactivity with human growth hormone, placental lactogen, follicle-stimulating hormone, thyroid-stimulating hormone, and luteinizing hormone at tonic and surge levels. The antibodies were competent for neutralizing the biological activity of HCG in the mouse uterine weight gain assay, the ventral prostate weight gain assay, and the radioligand assay for binding of 125I-labeled HCG to receptors on corpus luteum. HCG (5000 international units) administered to an immunized subject was completely bound by circulating antibodies. Administration of HCG (in contrast to conjugate) was without booster effect on anti-HCG titers.