Obesity aggravates neuroinflammatory and neurodegenerative effects of bisphenol A in female rats.

Bisphenol A (BPA), a common plasticizer, is categorized as a neurotoxic compound and its impact on individuals exhibits sex-linked variations. Several biological and environmental factors impact the degree of toxicity. Moreover, nutritional factors have profound influence on toxicity outcome. BPA has been demonstrated to be an obesogen. However, research on the potential role of obesity as a confounding factor in BPA toxicity is lacking. We studied the neurodegenerative effects in high-fat diet (HFD)-induced obese female rats after being exposed with BPA (10 mg/L via drinking water for 90 days). Four groups were taken in this study - Control, HFD, HFD + BPA and BPA. Cognitive function was evaluated through novel object recognition (NOR) test. Inflammatory changes in brain, and changes in hormonal level, lipid profile, glucose tolerance, oxidative stress and antioxidants were also determined. HFD + BPA group rats showed a significant decline in NOR test. The cerebral cortex (CC) of the brain showed increased neurodegenerative changes as measured by microtubule associated protein-2 (MAP-2) accompanied by histopathological confirmation. The increased level of neuroinflammation was demonstrated by microglial activation (Iba-1) and protein expression of nuclear factor- kappa B (NF-КB) in the brain. Obesity also caused significant (p < 0.05) increase in lipid peroxidation accompanied by reduced activities of antioxidant enzymes (glutathione S-transferase, catalase and glutathione peroxidase) and decrease in reduced-glutathione (p < 0.05) when compared to non-obese rats with BPA treatment. Overall, study revealed that obesity serves as a risk factor in the toxicity of BPA which may exacerbate the progression of neurological diseases.

Bagarius bagarius, and Eichhornia crassipes are suitable bioindicators of heavy metal pollution, toxicity, and risk assessment.

Water quality index (WQI) of Narora channel and health of endemic fish Bagarius bagarius and plant Eichhornia crassipes, district Bulandshahar, Uttar Pradesh, India were studied. Among the physicochemical properties of water, pH, D.O, Cr, Fe, Ni, and Cd were above the recommended standards. These factors lead to high WQI (4124.83), indicating poor quality and not suitable for drinking and domestic usage. In fish tissues, the highest metal load was reported in the liver (58.29) and the lowest in the kidney (33.73). Heavy metals also cause a lowering of condition indices. As expected, decreased serum protein (- 63.41%) and liver glycogen (- 79.10%) were recorded in the exposed fish. However, blood glucose (47.22%) and serum glycogen (74.69%) showed elevation. In the plant, roots (21.50) contained the highest, and leaves (16.87) had the lowest heavy metal load. Bioaccumulation factor (BAF) > 1, indicates hyperaccumulation of all metals. E. crassipes roots showed the highest translocation factor (TF) > 1 for Ni (1.57) and Zn (1.30). The high mobility factor (MF) reflected the suitability of E. crassipes for phytoextraction of Mn, Cd, Zn, Fe, Ni, and Cu. Moreover, Bagarius sp. consumption could not pose any non-cancer risk. Although, lower cancer risk can be expected from Ni and Cr.

Redox Status, Immune Alterations, Histopathology, and Micronuclei Induction in Labeo rohita Dwelling in Polluted River Water.

In this study, we measured various parameters of oxidative stress, immune response, and abnormalities in the erythrocyte nucleus of Labeo rohita inhabiting the polluted Kshipra River, India. The river water contains heavy metals in this order: Ni > Fe > Cd > Cr > Mn > Zn > Cu. Fe showed the highest accumulation in gills, liver, and gut, whereas Ni (gills and gut) and Cd (liver) were lowest accumulated. The superoxide dismutase (SOD) and catalase (CAT) were found to be increased significantly (p < 0.05) in the gills (SOD: 211%; CAT: 150%), liver (SOD: 447%; CAT: 304%), and gut (SOD: 98.11%; CAT: 58.69%) in comparison with the reference fish. However, glutathione S transferase (GST) showed significantly (p < 0.05) higher activity in the gills (25.5%) but lower activity in the liver (- 49.22%) and the gut (- 30.57%). Moreover, reduced glutathione (GSH) decreased significantly (p < 0.05) in the gills (- 46.66%), liver (- 33.20%), and gut (- 39.87%). Despite the active response of the antioxidant enzymes, the highest lipid peroxidation was observed in the liver (463%). The effect of heavy metals was also observed on the immunity of the fish, causing immunosuppression as evident by significantly (p < 0.05) lower values of acid phosphatase (- 50%), myeloperoxidase (- 48.33%), and nitric oxide synthase (- 50%) in serum. Histopathological findings showed gill lamellae shortening, hyperplasia, club-shaped lamellar tip in exposed gills and necrosis, vacuolization, and pyknosis in the exposed liver. Furthermore, polluted river water was also found to induce micronuclei (2.1%) and lobed nuclei (0.72%) in erythrocytes (0.65%). These results indicate the potential of heavy metal-induced oxidative stress and other forms of stress in inhabiting fish, highlighting the need to control the pollution of this river water.

Water quality index, Labeo rohita, and Eichhornia crassipes: Suitable bio-indicators of river water pollution.

The present study investigated the water quality index (WQI) of the Kshipra river at Dewas, Madhya Pradesh, India, using native fish Labeo rohita, and plant Eichhornia crassipes. The temperature, pH, dissolved oxygen, alkalinity, turbidity, and dissolved solids were found to be within the prescribed limits. However, heavy metals concentration exceeded the limit except for Cu and Zn. Their occurrence in river water was as follows: Ni > Fe > Cd > Cr > Mn > Zn > Cu. Among these heavy metals, Cd was found to be highly bioavailable, whereas Zn was the least bioavailable metal. Based on WQI, the water was found to be unfit for drinking, and the high WQI value was due to the presence of Cr and Cd. In fish tissues (muscle, liver, gut, gills, and kidney), the highest and lowest metal pollution index was found in gills (45.03) and kidneys (12.21), respectively. Bioaccumulation of these metals resulted in significant depletion of energy reserves (protein, glucose, and glycogen) and also altered hematological parameters. Moreover, liver function tests showed hepatic damage in the exposed fish. In-plant, both the bioaccumulation and mobility factor exceeded 1 for all these metals. On the other hand, the translocation factor was found to be beyond 1 for Fe, Ni, and Zn. These high values make this plant fit for phytoextraction of Mn, Fe, Cu, Zn, and Cd and phytostabilization of Cr in water. Moreover, consumption of L. rohita from the Kshipra River does not pose a non-cancer risk as the target hazard quotient was below 1, but it may pose cancer risk because of the presence of Cr in the range of 1.402 × 10-3 to 1.599 × 10-3.

Bioaccumulation of heavy metals and their toxicity assessment in Mystus species.

This study was conducted on two native fish species namely Mystus vittatus and Mystus tengara inhabiting challenging environment of Yamuna River. The heavy metals concentrations in the river water were found to be as follows: Fe > Mn > Zn > Cu > Ni > Cr > Cd, all above the Bureau of Indian Standards (BIS) and World Health Organization (WHO) guidelines. The high metal pollution index in gill, liver, and kidney of M. vittatus was recorded compared to M. tengara. The pathology caused by the accumulation of heavy metals resulted significantly (p < 0.05) higher enzyme activities of alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and creatinine kinase (CK) in M. tengara as compared to M. vittatus. However, albumin: globulin ratio was found to be below 0.8 in both fishes. Higher total leukocyte (TLC) (48.5 × 103/mm3), lymphocytes (40%), respiratory burst activity (1.9), and nitric oxide synthase (NOS) activity (13.11 U/L) in M. vittatus reflect high immune response. In addition, chromosomal breakage study showed significantly (p < 0.05) low micronuclei frequency, lobed nuclei, and kidney-shaped nuclei (KSN) in M. vittatus. These results indicate that under the same challenging conditions M. vittatus have more capability of resistance and its continuous survival points towards its suitability to serve as a bioindicator than M. tengara.

Heavy metal pollution and risk assessment by the battery of toxicity tests.

The current study was carried out on dominant fish Oreochromis niloticus and water collected from the polluted Yamuna River, Agra, India. The heavy metals in water, recorded as follows: Fe > Mn > Zn > Cu > Ni > Cr > Cd and all were found to be above the prescribed limits. According to metal pollution index, exposed muscle (49.86), kidney (47.68) and liver (45.26) have been recorded to have higher bioaccumulation. The blood biochemical analysis of exposed O. niloticus indicated significant increase in activities of aspartate aminotransferase (+ 343.5%), alkaline phosphatase (+ 673.6%), alanine aminotransferase (+ 309.1%), and creatinine (+ 494.3%) over the reference. However, a significant decrease in albumin (A): globulins (G) ratio (- 87.86%) was observed. Similarly, the exposed fish also showed significant increase in total leucocyte count (+ 121%), differential leucocyte count, respiratory burst (+ 1175%), and nitric oxide synthase (+ 420%). The histological examination of liver and kidney showed tissue injury. Moreover, micronuclei (0.95%), kidney shaped nuclei (1.2%), and lobed nuclei (0.6%) along with DNA damage in the form of mean tail length in the liver (20.7 µm) and kidney (16.5 µm) was observed in the exposed O. niloticus. Potential health risk assessments based on estimated daily intake, target hazard quotient, hazard index, and target cancer risk indicated health risks associated with the consumption of these contaminated fishes. In conclusion, the present study showed that exposure to heavy metals contaminated water can alter immunological response; induce histopathological alterations and DNA damage in the studied fish. The consumption of this contaminated water or fish could have serious impact on human health.

D-ribose and pathogenesis of Alzheimer's disease.

It is estimated that the global prevalence of dementia will rise as high as 24 million and predicted to be double in every 20 years which is attributed to the fact that the ageing population is increasing and so more individuals are at risk of developing neurodegenerative diseases like Alzheimer's. Many scientists favored glycation of proteins such as tau, amyloid beta (Aß) etc. as one of the important risk factor in Alzheimer's disease (AD). Since, D-ribose shows highest glycation ability among other sugars hence, produces advanced glycation end products (AGEs) rapidly. However, there are several other mechanisms suggested by researchers through which D-ribose may cause cognitive impairments. There is a concern related to diabetic patients since they also suffer from D-ribose metabolism, may be more prone to AD risk. Thus, it is imperative that the pathogenesis and the pathways involved in AD progression are explored in the light of ribosylation and AGEs formation for identifying suitable diagnostics marker for early diagnosis or finding promising therapeutic outcomes.

Studies on conformational changes induced by binding of pendimethalin with human serum albumin.

Pendimethalin (PND) is a widely used herbicide in modern means of agricultural practices. So, its toxic residues exist extensively in the environment and can enter human body. Therefore, the in vitro interaction of PND with human serum albumin (HSA) has been explored by employing various biophysical, molecular docking and dynamics simulation studies as well as enzyme kinetics to unravel its binding mechanism. The binding constant of the PND-HSA complex was about 104 M-1 using Fluorescence quenching spectra. The negative value of Gibbs free energy change (ΔG0 = -32.0 kJ mol-1) indicates this interaction is a spontaneous process. A large negative ΔH0 and positive ΔS0 suggests that hydrophobic interactions and H-bonding are involved in the binding process of PND with HSA. The binding of PND can cause conformational and micro-environmental changes in HSA molecule, as shown by various biophysical and molecular dynamics simulation studies. The site marker competition and molecular docking and simulation experiments affirmed that the binding of PND to HSA occurs at or near site I. Esterase-like activity of HSA exhibited decline in the presence of PND revealed the direct involvement of Lys199 of subdomain IIA (Sudlow's site I) in the binding process.

Pendimethalin-induced oxidative stress, DNA damage and activation of anti-inflammatory and apoptotic markers in male rats.

Male Wistar rats were exposed to herbicide, pendimethalin (PND) at varying oral doses of 62.5, 125 and 250 mg/kg b.w. for 14 days. Toxiological effects were assessed in terms of oxidative stress, DNA damage, histopathological alterations and induction of anti-inflammatory and apoptotic responses linked Bax, Bcl-2, IFN-γ, TNF-α and caspase-3 gene expression. In comparison with respective untreated controls, all exposure groups of PND exhibited significant changes in the oxidative stress markers (protein carbonylation and lipid peroxidation) and antioxidant defenses (GSH, SOD, CAT and GST) in liver and kidney tissues. The histopathological changes including leucocyte infiltration, pyknotic nuclei, necrosis, large bowman's space, shrinked renal cortex, were observed in the liver and kidney tissues of PND exposed rats. Significant DNA damage was recorded through comet assay in liver and kidney cells of treated animals as compared to control. Alteration in anti-inflammatory and apoptotic genes expression determined by RT-PCR, revealed the activation of intrinsic apoptotic pathway(s) under the PND induced cellular stress. A pronounced increase in Bax expression, caspase-3 activities and decreased Bcl-2 expressions were also associated with PND-induced apoptosis. Data from this study suggests that PND induces cellular toxicity and genetic perturbations which can alter the normal cellular and physiological functioning in rats.

Publisher Correction: Multiple biomarker responses (serum biochemistry, oxidative stress, genotoxicity and histopathology) in Channa punctatus exposed to heavy metal loaded waste water.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

Multiple biomarker responses (serum biochemistry, oxidative stress, genotoxicity and histopathology) in Channa punctatus exposed to heavy metal loaded waste water.

Experiments were conducted to investigate the health of fish Channa punctatus inhabiting heavy metal-loaded waste water. Heavy metals in the order of Fe > Mn > Zn > Co > Ni > Cu = Cr were present in the waste water. Gills had high metal load followed by liver and then kidney. Albumin, albumin to globulin (A:G) ratio, triglyceride, high density lipoprotein (HDL) and very low density lipoprotein (VLDL) were found to be lower but phospholipid, low density lipoprotein (LDL), total protein, lipid and cholesterol were higher as compared to the reference. Oxidative stress markers such as superoxide dismutase (SOD), catalase (CAT), glutathione S transferase (GST) and lipid peroxidation (LPO) were significantly higher in all tissues, whereas reduced glutathione (GSH) levels were comparatively low. Damage to DNA was observed with significantly higher mean tail length of comets in the exposed fish gill cells (30.9 µm) followed by liver (24.3 µm) and kidney (20.6 µm) as compared to reference fish (5.2, 4.8 and 5.9 µm respectively). Histopathology in gill, liver and kidney also showed marked damage. Integrated biochemical, oxidative stress, genotoxicity and histopathological findings are valuable biomarkers for native fish adaptive patterns, and monitoring of water quality/pollution of freshwater ecosystems.

Studies on the alterations in haematological indices, micronuclei induction and pathological marker enzyme activities in Channa punctatus (spotted snakehead) perciformes, channidae exposed to thermal power plant effluent.

The present study was conducted to assess the toxicity of thermal power plant effluent containing heavy metals (Fe > Cu > Zn > Mn > Ni > Co > Cr) on haematological indices, micronuclei, lobed nuclei and activity of pathological marker enzymes [alkaline phosphatase (ALP), aspartate transferase (AST), alanine transferase (ALT) and creatine kinase (CK)] in Channa punctatus. Total erythrocyte count (-54.52 %), hemoglobin (-36.98 %), packed cell volume (-36.25 %), mean corpuscular hemoglobin concentration (-1.41 %) and oxygen (O2) carrying capacity (-37.04 %) declined significantly over reference fish, however total leukocyte count (+25.43 %), mean corpuscular hemoglobin (+33.52 %) and mean corpuscular volume (+35.49 %) showed elevation. High frequency of micronuclei (1133.3 %) and lobed nuclei (150 %) were observed in exposed fish which may indicate mutagenesis. Activities of pathological marker enzymes ALP, AST, ALT and CK increased significantly in serum of exposed fish. The ratio of ALT: AST in exposed fish was beyond 1 which indicates manifestation of pathological processes. These biomarkers show that fish have macrocytic hypochromic anemia. Leukocytosis showed general defence response against heavy metal toxicity and marker enzymes showed tissue degeneration. In conclusion, thermal power plant effluent has strong potential to induce micronuclei, tissue pathology, making the fish anemic, weak, stressed and vulnerable to diseases.

Accumulation of heavy metals and human health risk assessment via the consumption of freshwater fish Mastacembelus armatus inhabiting, thermal power plant effluent loaded canal.

Bioaccumulation of six heavy metals (Mn, Fe, Co, Ni, Cu, Zn) in the muscle of highly consumed fish species (Mastacembelus armatus) were measured using atomic absorption spectrometer. Fe (213.29 mg/kg dry weight) concentration was the most, followed by Zn (186.19 mg/kg dry weight), Ni (58.98 mg/kg dry weight), Cu (41.36 mg/kg dry weight), Co (9.06 mg/kg dry weight) and Mn (9.03 mg/kg dry weight). Estimated daily intake of heavy metals was calculated by mean fish consumption rate 19.5 × 10(-3) kg/day, on the basis of a calculation of the amount of fish consumed by adult individuals (male and female). The studied fish species pose non carcinogenic risk for Co and Ni [target hazard quotient (THQ) > 1] only. Hazard index (HI) was high. Carcinogenic risk (TR) posed by this fish for male and female was 3.43 × 10(-3) and 3.91 × 10(-3), respectively for Ni (the carcinogenic potency slope factor was available for Ni only). The study is an alert indicating that inhabitants who consume these fishes (particularly females) were at risk of Co and Ni toxicity. In India recommended guidelines have yet not been established for these heavy metals, which is essential for setting of toxicological standards.

Studies on biomarkers of oxidative stress and associated genotoxicity and histopathology in Channa punctatus from heavy metal polluted canal.

Some investigations were made on the Satha canal water and health of dwelling fish Channa punctatus at Satha village, district Aligarh (U.P). Metal bioaccumulation and induction of biomarkers such as lipid peroxidation (LPO), superoxide dismutase (SOD), catalase (CAT), glutathione S transferase (GST), reduced glutathione (GSH), DNA damage and histopathology are potential indicators of stress in C. punctatus exposed to effluents. In canal water Cr, Mn, Fe and Ni concentrations were exceeding the permissible limits set by both Bureau of Indian standards (BIS) and WHO. Fe (74%) was highly bioavailable and accumulated in all organs (gill, liver, kidney, muscle and integument). The highest metal pollution index (MPI) value of 53 was observed in gills and the lowest 6 in liver tissue. SOD and LPO were significantly higher in all tissues, whereas CAT, GST and GSH levels declined significantly compared to fish from the reference site. Concomitant damage to DNA was observed with significantly higher mean tail length in the exposed fish gill cells (19 µm) and in liver (12.7 µm) compared to reference fish (5 and 4 µm respectively). Histopathology in gill and liver also show significant damage. Therefore, it can be concluded that the sugar mill effluent has the potential to cause oxidative stress, DNA damage and histopathology in C. punctatus. This canal is a prime source of water and fish food to the local residents of the area. Therefore, the consumers may suffer adverse health effects like that in indicator organism.

Bioaccumulation, oxidative stress and genotoxicity in fish (Channa punctatus) exposed to a thermal power plant effluent.

Metal bioaccumulation and induction of biomarkers such as lipid peroxidation (LPO), superoxide dismutase (SOD), catalase (CAT), glutathione S transferase (GST), reduced glutathione (GSH) and DNA damage are potential indicators of stress in Channa punctatus exposed to effluents. In canal water, receiving thermal power plant discharges, Fe and Ni concentrations exceeded the recommended guidelines set by the United Nations Environment Programme Global Environment Monitoring System (UNEPGEMS). Fe was highly bioavailable and accumulated in all organs (liver, kidney, muscle and integument). The highest metal pollution index (MPI) value of 41.2 was observed in kidney and the lowest 13.5 in muscle tissue. LPO, SOD, CAT and GST levels were significantly higher in liver and kidney, whereas GSH levels declined significantly compared to fish from the reference site. Concomitant damage to DNA was observed with significantly higher mean tail length in the exposed fish gill cells (26.5µm) and in liver (20.8µm) compared to reference fish. Therefore, it can be concluded that the thermal power plant effluent had the potential to cause oxidative stress and DNA damage in C. punctatus.

Stress response of biomolecules (carbohydrate, protein and lipid profiles) in fish Channa punctatus inhabiting river polluted by Thermal Power Plant effluent.

Qualitative and quantitative assessment of heavy metals in the Thermal Power Plant effluent was performed to study the impact of their toxic effects on various biomarkers (carbohydrate, protein and lipid profiles). Heavy metals present in the water were in the order Fe > Cu > Zn > Mn > Ni > Co > Cr. Fe and Ni exceeded and Cr was equal to the USA standards set by UNEPGEMS. Glycogen in liver (p < 0.001) and muscle (p < 0.01) depleted significantly. Insignificant (p < 0.05) decline in blood glucose (-21.0%) and significant (p < 0.05) elevation in both total protein and globulin in serum, liver and muscle was noted. Albumin decreased significantly (p < 0.01) in serum but showed significant (p < 0.05) increase in liver and muscle. Thus A:G ratio fell in serum and rose in liver and muscle. Similarly lipid profile also gets altered where significant elevation in serum total lipid (p < 0.01), total cholesterol (p < 0.01), phospholipid (p < 0.05), triglycerides (p < 0.001), LDL (p < 0.01) was observed but significant (p < 0.05) decline in VLDL was recorded. These biomarkers suggested that fish become hypoglycemic, hyperlipidemic and hypercholesterolemic. Heavy metals also provoked immune response as evident from the rise in globulin. In conclusion the Thermal Power Plant wastewater containing heavy metals induced stress, making fish weak and vulnerable to diseases.

Studies on the oxidative stress and gill histopathology in Channa punctatus of the canal receiving heavy metal-loaded effluent of Kasimpur Thermal Power Plant.

Some investigations were made on the canal water and inhabiting fish Channa punctatus at Kasimpur, district Aligarh (U.P.). It is a prime source for drinking, washing, and irrigation which was found to be receiving effluent from the adjoining Harduaganj Thermal Power Plant. The water samples were found to contain heavy metals, and the values obtained for Fe (8.71 mg L(-1)) and Ni (0.12 mg L(-1)) were beyond the recommended levels set by UNEPGEMS. C. punctatus was found to be the predominant fish in this canal. Fishes' gills are directly exposed to the ambience; hence, the changes are expected to be more prominent. Among the analyzed heavy metals, bioaccumulation of Zn (500.41 mg kg(-1) dry weight (dw)) was highest and Ni (13.93 mg kg(-1) dw), the least. Increased levels of lipid peroxidation (LPO) as well as antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione-S-transferase (GST) were found in the gills of the test fishes. The level of reduced glutathione (GSH), a nonenzymatic antioxidant, was quite expectedly lower than that in the reference fish. The gills of inhabiting fishes contained several lesions like necrosis, epithelial lifting, lamellar fusion, hyperplasia, syneching, infiltration of lymphocytes, and bridging in gill tissue. The present study demonstrated that wastewater/effluent released from thermal power plant containing heavy metals has strong potential to affect the physicochemical properties of the water and well-being of aquatic living organisms.

Assessment of heavy metal (Cu, Ni, Fe, Co, Mn, Cr, Zn) pollution in effluent dominated rivulet water and their effect on glycogen metabolism and histology of Mastacembelus armatus.

The present study was conducted to examine the contamination of rivulet situated at Kasimpur, Aligarh (27.218° N; 79.378° E). It receives the wastewater of Harduaganj Thermal Power Plant (HTPS) containing fly ash and heavy metals. Among the heavy metals estimated in the rivulet water, Fe (8.71 mgL(-1)) was present in the highest concentration followed by Cu (0.86 mgL(-1)), Zn (0.30 mgL(-1)) Mn (0.21 mgL(-1)), Ni (0.12 mgL(-1)), Co (0.11 mgL(-1)) and Cr (0.10 mgL(-1)). The values for the heavy metals such as Fe, Ni and Mn were beyond the limits set by UNEPGEMS. Bioaccumulation of these heavy metals was detected in tissues such as gills, liver, kidney, muscle and integument of the fish Mastacembelus armatus. Accumulation of Fe (213.29 - 2601.49 mgkg(-1).dw) was highest in all the organs. Liver was the most influenced organ and integument had the least metal load. The accumulation of Fe, Zn, Cu and Mn, observed in the tissues were above the values recommended by FAO/WHO. Biochemical estimation related to blood glucose, liver and muscle glycogen conducted showed significant (p < 0.01) elevation in blood glucose content over control (17.73%), whereas liver glycogen dropped significantly (p < 0.01) over control (-89.83%), and similarly muscle glycogen also decreased significantly (p < 0.05) over control (-71.95%), suggesting enhanced glycolytic capacity to fuel hepatic metabolism. Histopathological alterations were also observed in selected organs (gills, liver and kidney) of Mastacembelus armatus.