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Background: Left bundle branch area pacing(LBBAP) results in right bundle branch(RBB) delay pattern due to pre-excitation of the left-bundle. The mechanism of right-ventricular(RV) activation during LBBAP is largely unknown OBJECTIVES: The aim of the study is to analyze the electrophysiological characteristics pf RV activation by mapping the RBB during LBBAP and its clinical correlation., Methods: Consecutive patients who underwent successful LBBAP were included. RBBB, RV-paced rhythm or suboptimal intracardiac electrograms were excluded. LBBAP was performed with continuous recording of His-bundle(HB) and RBB-electrograms. RV activation was classified into 3 types based on the intracardiac electrogram -(a) type-I(RBB mediated) (b) type-II(transeptal activation) and (c) type-III(fusion pattern)., Results: Overall 86 patients(94% LBBP;6%LVSP) were included. Mean age 59.6±12.8 years. Non-selective to selective capture transition was noted in 85%(n=73). In patients with baseline normal QRS(n=47), during selective-LBBP(S-LBBP;n=39) the most common pattern was type-I(n=35;87%) while during non-selective LBBP(NS-LBBP;n=44) type-III patten(n=40;91%) was common. In patients with LBBB(n=39), type-III pattern was common during both S-LBBP and NS-LBBP. Type-I pattern was noted only in patients with retrograde HB-activation during S-LBBP. LVSP showed type-II activation in both groups. Patients without retrograde HB activation had higher LV end-diastolic diameter, lower LVEF and prolonged HV-interval as compared to those with retrograde HB activation., Conclusion: Physiological RBB mediated (type-I) activation of the RV was the most common pattern observed during S-LBBP in patients with intact retrograde HB activation. Type-III pattern was the most common pattern observed during NS-LBBP with fusion of multiple wavefronts from anterograde RBB activation, septal myocardial, and transverse inter-bundle connections., (Copyright © 2024. Published by Elsevier Inc.)

Coastal pollutants, from harmful algal blooms, sewage and industrial discharges, pose severe risks to marine ecosystems and public health. Recently, Promenade Beach in Puducherry, Southeast-India, experienced reddish-brown water discoloration, suspected to result from either algal blooms or suspended matter. This study monitored the spatial extent and characteristics of the discoloration using Sentinel-2 satellite images from September to November 2023, with field observations and laboratory analyses. Analyses included measurements of chlorophyll-a (Chl-a), Total Suspended Matter (TSM), and the Normalized Difference Chlorophyll Index (NDCI) to differentiate between algal blooms and other pollutants. The satellite data indicated extents of discoloration, with high TSM concentrations (>45 g/m 3 ) and negative NDCI values suggesting absence of algal blooms. No mortality of aquatic organisms was observed during this discoloration, indicating no deleterious impact on aquatic life. This approach highlights the importance of combining satellite technology with field data for effective coastal pollution monitoring, essential for protecting marine ecosystems., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. We wish to confirm that there are no known conflicts of interest associated with this publication., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Dense and green-coloured patches were encountered on the sea surface waters of the Tuticorin coast on 22 nd October 2022. Microscopic investigation revealed that the discoloration is caused by plankton, green Noctiluca scintillans. In order to find out the causes that trigger the bloom of N. scintillans, plankton samples were collected for 5 days in fourteen days duration from 22 nd October to 4 th November. During the peak bloom period, the abundance and biovolume of N. scintillans reached 1.56 × 10 4  cells/L and 21.8 × 10 10 μm 3 /L, respectively. The highest concentration (73.65 mg/m 3 ) of chlorophyll-a was recorded during blooming period that was caused by Gonyaulax polygramma and endosymbiont, Pedinomonas noctilucae in N. scintillans. Formation of G. polygramma bloom is being reported for the first time in Tuticorin, southeast coast of India, with a species abundance of 36.9 × 10 4  cells/L. Present study concluded that besides the optimum hydrological conditions and eutrophic nature of the system, abundant prey (G. polygramma) facilitated the N. scintillans bloom., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. We wish to confirm that there are no known conflicts of interest associated with this publication., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Various biotic and abiotic factors regulate carbon dioxide (CO 2 ) absorption and emission in coastal waters. Factors controlling the regional air-sea CO 2 fluxes were studied in Tuticorin Bay, a highly urbanized region along the southeast coast of India. Significant spatial heterogeneity in the distribution of inorganic carbon components in the bay was observed based on the exposure to different anthropogenic pressures. Thermal effluent discharges made the south zone of the bay a strong CO 2 source by enhancing heterotrophy. Untreated sewage discharges in the middle zone mediated eutrophic conditions leading to strong autotrophy and restricting the zone as a weak source of CO 2. Irrespective of the anthropogenic stressors, biological processes dominated the air-sea CO 2 fluxes in the Tuticorin Bay. The results indicated that micro-level studies are needed in understanding the carbon cycle in environments with multiple anthropogenic stressors., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

In this study, we identified the in situ bacterial groups and their community structure in coastal waters influenced by anthropogenic inputs. The use of environmental DNA (eDNA) and high throughput sequencing (HTS) were employed to derive accurate and reliable information on bacterial abundance. The V3 and V4 hypervariable regions of the 16S rRNA gene were amplified and the sequences were clustered into operational taxonomic units to analyze the site-specific variations in community composition. The percentage composition within the bacterial orders varied significantly among nearshore anthropogenic hotspots and offshore (5 km) samples. The microbial network constructed taking the bacterial abundance as nodes displayed strong positive and negative correlations within the bacterial families. Overall, the use of eDNA coupled with HTS is an incredible means for monitoring and assessing the abundance of bacterial communities and also serves as a biomonitoring tool to understand the degree of anthropogenic contamination in coastal waters., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The influence of upwelling on the phytoplankton community was examined during the upwelling-relaxation period in the southeastern Arabian Sea. Elevated upwelling intensity during the summer monsoon season of 2016 resulted in the re-suspension of harmful dinoflagellates into the surface water. Further, the surplus of phosphorus (P) inputs into the coastal waters from estuarine runoff during the upwelling-relaxation period induced blooming of Gonyaulax polygramma (4.9 × 10 6 cells L -1 ). Results from canonical correspondence analysis revealed that elevated upwelling intensity, P and salinity during the year 2016 likely triggered the bloom of G. polygramma in the study region. HABs like G. polygramma threaten fish stocks such as sardines which have a vital role in the ecosystem. Studies on phytoplankton communities and nutrient dynamics in upwelling systems would be useful in predicting the incidence/toxic effects of harmful algal blooms as these regions have a high potential for fisheries., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Owing to the environmental sensitivity of ciliate species, the monitoring and assessment of these communities can indicate the health of the aquatic environment. Sampling for loricate ciliates was carried out during different seasons at three different locations in the estuarine and coastal waters of Kochi, Southwest coast of India. The loricate ciliate community comprising of 27 species belonging to 10 genera revealed significant differences among the three sampling locations. The maximum numerical abundance and less species diversity of loricate ciliates were recorded at the estuarine locations whereas the minimum abundance and more species diversity were encountered in the coastal waters. Multivariate statistical analyses revealed that Tintinnopsis beroidea and Tintinnopsis uruguayensis were correlated positively with nutrients in the estuarine environment, which receives large amount of anthropogenic inputs. Thus, we propose that these two loricate ciliates may be considered as a potential bioindicator of eutrophication status in marine ecosystems., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Nitrous oxide (N(2)O) emissions from Vertisols and Alfisols during sweet sorghum cultivation in the Indian semi-arid tropics were determined using a closed chamber technique during the rainy season (June-October) of 2010. The study included two treatments, nitrogen (N) at a rate of 90 kg/ha and a control without N fertilizer application. The N(2)O emissions strongly coincided with N fertilization and rainfall events. The cumulative N(2)O-N emission from Alfisols was 1.81 N(2)O-N kg/ha for 90 N treatment and 0.15 N(2)O-N kg/ha for the 0 N treatment. Similarly, the N(2)O-N emission from Vertisols was 0.70 N(2)O-N kg/ha for 90 N treatment and 0.09 N(2)O-N kg/ha for the 0 N treatment. The mean N(2)O-N emission factor for fertilizer induced emissions from the Alfisols was 0.90% as compared to 0.32% for Vertisols. Our results suggest that the N(2)O emissions are dependent on the soil properties. Therefore, the monitoring of N(2)O emissions from different agro-ecological regions, having different soil types, rainfall characteristics, cropping systems and crop management practices are necessary to develop comprehensive and accurate green house gas inventories., (Copyright © 2012 Elsevier B.V. All rights reserved.)

The Environmental Specimen Bank (es-BANK) for Global Monitoring at the Center for Marine Environmental Studies, Ehime University, Japan has more than four decades of practical experience in specimen banking. Over the years, es-BANK has archived specimens representing a wide range of environmental matrices, i.e. fishes, reptiles, birds, aquatic mammals, terrestrial mammals, human, soils, and sediments. The samples have been collected as part of the various monitoring programs conducted worldwide. The current review is a summary of selected studies conducted at the Center for Marine Environmental Studies, on temporal and spatial trends of legacy and emerging contaminants in the marine environment. One of the major conclusions drawn from the studies is that environmental problems are no more regional issues and, thus, environmental specimen banking should not be limited to national boundaries, but should have a global outlook., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Trace elements (TEs) and stable isotope ratios (delta(15)N and delta(13)C) were analyzed in fish from deep-water of the Sulu Sea, the Celebes Sea and the Philippine Sea. Concentrations of V and Pb in pelagic fish from the Sulu Sea were higher than those from the Celebes Sea, whereas the opposite trend was observed for delta(13)C. High concentrations of Zn, Cu and Ag were found in non-migrant fish in deep-water, while Rb level was high in fish which migrate up to the epipelagic zone, probably resulting from differences in background levels of these TEs in each water environment or function of adaptation to deep-water by migrant and non-migrant species. Arsenic level in the Sulu Sea fish was positively correlated with delta(15)N, indicating biomagnification of arsenic. To our knowledge, this is the first study on relationship between diel vertical migration and TE accumulation in deep-water fish., (Copyright 2010 Elsevier Ltd. All rights reserved.)

Twelve species of deep-sea fishes collected in 2005 from the western North Pacific, off-Tohoku, Japan were analyzed for organohalogen compounds. Among the compounds analyzed, concentrations of DDTs and PCBs (up to 23,000 and 12,400 ng/g lipid wt, respectively) were the highest. The present study is the foremost to report the occurrence of brominated flame retardants such as PBDEs and HBCDs in deep-sea organisms from the North Pacific region. Significant positive correlations found between delta(15)N ( per thousand) and PCBs, DDTs and PBDEs suggest the high biomagnification potential of these contaminants in food web. The large variation in delta(13)C (per thousand) values observed between the species indicate multiple sources of carbon in the food web and specific accumulation of hydrophobic organohalogen compounds in benthic dwelling carnivore species like snubnosed eel. The results obtained in this study highlight the usefulness of deep-sea fishes as sentinel species to monitor the deep-sea environment., (Copyright 2009 Elsevier Ltd. All rights reserved.)

Organohalogen contaminants including PCBs, DDTs, CHLs, HCHs, HCB, PBDEs and HBCDs were determined in striped dolphins (Stenella coeruleoalba) found stranded at Gogo-shima (n=6, 2003) and collected from Taiji (n=15, 1978-1992) in Japan. All target compounds were significantly detected in all the specimens, indicating ubiquitous contamination of oceanic cetaceans in northwest Pacific Ocean. Examination of body distribution of organohalogens in the six specimens from Gogo-shima showed no significant difference in concentrations among the analyzed tissues, except for brain, which had lower levels possibly due to the existence of blood-brain barrier. For evaluating temporal trends, archived blubber samples of adult male stripped dolphins collected in 1978, 1979, 1986 and 1992 were analyzed. Concentrations of PCBs, DDTs and HCHs did not change significantly during 1978-2003. In contrast, remarkable increasing trends of PBDEs and HBCDs were observed, suggesting growing consumption in Japan and surrounding countries in recent years.

A sensitive assay for determination of rifalazil (also known as ABI-1648 and KRM-1648) in human plasma is described. The analytical method utilizes liquid-liquid extraction of plasma with methyl tert-butyl ether, followed by reversed-phase liquid chromatography with a C18 column and a mobile phase gradient utilizing 0.1% formic acid in water and acetonitrile, respectively. Electrospray mass spectrometry in the positive ion mode with selected reaction monitoring of rifalazil and an isotope labeled internal standard, 13C4-rifalazil (ABI-9901) was used for selective and sensitive detection. The calibration range was 0.050-50 ng/mL plasma using 200 microL plasma sample volume. The absolute extraction recovery of rifalazil from K2-EDTA plasma, evaluated at three concentration levels, was 88.6-97.3%, and the recovery for the internal standard was 96.8%. A study of plasma matrix effects showed a peak area response at 90-99% compared to neat solutions for both rifalazil and the internal standard. Stability evaluation of rifalazil in plasma, whole blood and methanol showed that the analyte stability was adequate when stored under study conditions. The precision, as evaluated in three validation batches, was consistent for fortified plasma quality control (QC) samples at four concentration levels, with < or =6% R.S.D. except for at the lowest quality control level where it was 10.7% R.S.D. The accuracy for QC samples (difference between found and nominal concentration) ranged from -2.3% to 5.1%. Similar precision and accuracy values were obtained over 6 months of routine application of this method. It was concluded that the performance improved markedly during routine operation by replacing a closely related structural analog internal standard with the stable isotope internal standard.

A diastereoisomer (alpha, beta, and gamma) specific analytical method for measuring hexabromocyclododecanes (HBCDs) was developed using liquid chromatography-tandem mass spectrometry (LC-MS-MS). The method developed was applied to analyze blubber of small cetaceans to divulge the distribution and temporal variation of HBCDs in the Asian marine environment. HBCDs were detected in all the blubber samples of finless porpoises (Neophocaena phocaenoides) and Indo-Pacific humpback dolphins (Sousa chinensis) collected from the South China Sea during 1990-2001. Concentrations of HBCDs were higher in humpback dolphins (31-380 ng/g lipid) than in finless porpoises (4.7-55 ng/g lipid), which can be attributed to habitat differences. Average concentrations of alpha-HBCD in finless porpoises increased from 9.5 ng/g lipid in 1990 to 35 ng/g lipid in 2000/01. alpha-HBCD was predominant among the three isomers with some exceptions in finless porpoises collected in 1990. This is the first report on HBCDs contamination in marine mammals from Southeast Asia.

The testosterone metabolite 3alpha-androstanediol (5alpha-androstane-3alpha,17-diol) is a potential GABA(A) receptor-modulating neurosteroid with anticonvulsant properties and hence could act as a key neuromodulator in the central nervous system. However, there is no specific and sensitive assay for quantitative determination of the androgenic neurosteroid 3alpha-androstanediol in biological samples. We have established a liquid chromatography-tandem mass spectrometry (LC-MS-MS) assay to measure 3alpha-androstanediol in rat plasma. Standard 3alpha-androstanediol added to rat plasma has been successfully analysed with excellent linearity, specificity, sensitivity, and reproducibility. The sensitivity of the method was < 10 ng/ml with a detection limit of 2 ng/ml (6.8 nmol/l) and a linear range of 10-2000 ng/ml. The method was used for the analysis of testosterone-induced increase in plasma 3alpha-androstanediol levels in rats. Testosterone produced a dose-dependent elevation in plasma 3alpha-androstanediol, which was almost completely prevented by pretreatment with the 5alpha-reductase inhibitor finasteride, indicating that 3alpha-androstanediol is synthesized from testosterone via a 5alpha-reductase pathway. This LC-MS-MS method allows accurate, high-throughput analysis of 3alpha-androstanediol in small amounts (200 microl) of plasma and possibly other biological samples.

Polybrominated diphenyl ethers (PBDEs) and organochlorine compounds (OCs) were determined in the blubber, liver and kidney of Indo-Pacific humpback dolphins (Sousa chinensis) and finless porpoises (Neophocaena phocaenoides) stranded in Hong Kong coastal waters during 1995-2001. Among the organohalogen compounds analyzed, DDTs were the most dominant contaminants with concentrations ranging from 9.9 to 470 microg/g lipid wt. PBDEs in Hong Kong cetaceans, which are reported for the first time, were detected in all the samples with values ranging from 0.23 to 6.0 microg/g lipid wt., with a predominance of BDE-47. Results from this study suggest PBDEs should be classified as priority pollutants in Asia. Higher concentrations were found in humpback dolphins than in finless porpoises, and this was attributed mainly to differences in habitat. Elevated residues of PCBs and DDTs in some cetaceans suggest these species may be at risk.

A method for determining concentration levels of Co 102862 in mouse, rat, monkey and dog plasma was validated in the range of 5 to 2000 ng/ml using 200 microl plasma sample volume. This validation report describes the linearity, specificity, sensitivity, reproducibility, accuracy, recovery and stability of the analytical method. The inter-day RSD ranged from 3.5 to 10.1%, intra-day RSD from 0.6 to 5.7% and intra-day accuracy (mean absolute percent difference) ranged from 2.2 to 14.9% for rat, monkey and dog plasma. A mini-validation (5-2000 ng/ml) of Co 102862 was performed in mouse plasma using the same methods. Additionally, the assay range at the low end was successfully extended to 0.5 ng/ml for monkey plasma. The method was used for the routine analysis of Co 102862 in mouse, rat, monkey and dog plasma and summary of the pharmacokinetic data are presented.

A method was developed to quantitate the glucuronide conjugates (phase II metabolites, log P = 0.6-1.8) of the phase I hydroxylated metabolites (log P = 2.6-2.7) of beta-arteether (2) (log P = approximately 4.0) in rat plasma and urine. The biological fluids were extracted with a C-18 solid-phase cartridge, then subjected to analysis by thermospray high-performance liquid chromatography/mass spectroscopy with a C-18 reversed-phase analytical column in the selected ion monitoring mode. The detection limits for these glucuronide conjugates in plasma and urine ranged from 25 to 60 ng/mL, and the detection limits were appropriate for the biological activity of these glucuronide conjugates in plasma. Following intravenous administration of arteether (11.6 mg/kg), the formation of these glucuronide conjugates in rat urine was undetected (below detection limit) over 24 h. However, in rat plasma, formation of 9alpha-hydroxyarteether glucuronide (13; 255 ng/mL, IC50 = 6560 ng/mL, log P = 0.93) was noted at 15 min post-injection. Although several of the glucuronide metabolites of arteether retained sufficient in vitro antimalarial activity to be potentially useful antimalarial agents if administered as prodrugs, the levels of the glucuronides formed from arteether were too low to contribute to the antimalarial activity observed for the parent compound.