Mechanistic and recent updates in nano-bioremediation for developing green technology to alleviate agricultural contaminants

The rise in environmental pollutant levels in recent years is mostly attributable to anthropogenic activities such as industrial, agricultural and other activities. Additionally, these activities may produce excessive levels of dangerous toxicants such as heavy metals, organic pollutants including pesticide and herbicide chemicals, and sewage discharges from residential and commercial sources. With a focus on environmentally friendly, sustainable technology, new technologies such as combined process of nanotechnology and bioremediation are urgently needed to accelerate the cost-effective remediation process to alleviate toxic contaminants than the conventional remediation methods. Numerous studies have shown that nanoparticles possess special qualities including improved catalysis and adsorption as well as increased reactivity. Currently, microorganisms and their extracts are being used as promising, environmentally friendly catalysts for engineered nanomaterial. In the long term, this combination of both technologies called nano-bioremediation may significantly alter the field of environmental remediation since it is more intelligent, safe, environmentally friendly, economical and green. This review provides an overview of soil and water remediation techniques as well as the use of nano-bioremediation, which is made from various living organisms. Additionally, current developments related to the mechanism, model and kinetic studies for remediation of agricultural contaminants have been discussed.

Breed, Coat Color, and Hair Length as Risk Factors for Hyperthyroidism in Cats

Background

Hyperthyroidism is very common in older cats, but the etiopathogenesis is poorly understood. Decreased risk of hyperthyroidism has been reported in certain colorpoint breeds, and this observation previously has been hypothesized to result from relatively greater tyrosine availability for thyroid hormone production because of limited ability to convert tyrosine to melanin pigment. However, studies investigating a potential link between coat pigmentation and risk of hyperthyroidism are limited.

Objective

To identify associations between coat phenotype and hyperthyroidism by investigation of breed, coat color, and hair length as risk factors for the disease.

Animals

Data were used from 4,705 cats aged ≥10 years, referred to a single veterinary teaching hospital (2006–2014) in the United Kingdom.

Methods

Retrospective, epidemiological, cross‐sectional study using Bayesian multivariable logistic regression to assess risk factors for hyperthyroidism.

Results

Burmese (odds ratio [OR], 0.01; 0.00–0.23; P = .004), Tonkinese (OR, 0.05; 0.00–0.95; P = .046), Persian (OR, 0.21; 0.10–0.44; P < .001), Siamese (OR, 0.27; 0.12–0.61; P = .002), Abyssinian (OR, 0.04; 0.00–0.74; P = .031), and British shorthair (OR, 0.47; 0.28–0.79; P = .004) breeds had decreased risk of hyperthyroidism compared to domestic shorthairs. Longhaired, nonpurebred cats (OR, 1.30; 1.03–1.64; P = .028) were at increased risk of hyperthyroidism. Coat color/pattern was not associated with hyperthyroidism in nonpurebred cats.

Conclusions and Clinical Importance

We identified decreased risk of hyperthyroidism in the Tonkinese, Abyssinian, and British shorthair breeds, identified an association between risk of hyperthyroidism and hair length, and confirmed decreased risk in Burmese, Siamese, and Persian breeds. Additional studies are warranted to further investigate these findings.

Raman and XPS study on the interaction of taurine with silver nanoparticles

The SERS spectrum of taurine suggests the predominance of the gauche conformer with sulphonate and amino groups involved in binding.

Induction of a room temperature ferroelectric SmC* phase in binary mixtures with moderate spontaneous polarization and sub-millisecond switching time

Induction of room temperature SmC* phase in binary mixture.

Apoptosis induction in human leukemic cells by a novel protein Bengalin, isolated from Indian black scorpion venom: through mitochondrial pathway and inhibition of heat shock proteins

Scorpion venom possesses protein toxins having numerous biological activities, some of which are potentially anticancerous. Previously we had reported antiproliferative activity of the venom of Indian black scorpion, Heterometrus bengalensis Koch. Here we have isolated and purified a novel protein named Bengalin (72kDa) from the venom, responsible for antiproliferative and apoptogenic activities against human leukemic cells U937 (histiocytic lymphoma) and K562 (chronic myelogenous leukemia). N-terminal sequence of first 20 amino acids of Bengalin was G-P-L-T-I-L-H-I-N-D-V-H-A-A/R-F-E-Q/G-F/G-N-T. Bengalin induced cell growth inhibition at IC(50) values of 3.7 and 4.1 microg/ml for U937 and K562 cells respectively did not significantly affect normal human lymphocytes. Inhibition of U937 and K562 cell proliferation occurred by apoptosis as evidenced from damaged nuclei, cell cycle arrest at sub G1 phase, increase of early apoptotic cells, augmentation of DNA fragmentation and also a reduction of telomerase activity. Further insights revealed that Bax:Bcl2 ratio was elevated after Bengalin treatment. Moreover Bengalin elicited loss of mitochondrial membrane potential (MMP) which commenced cytochrome c release in cytosol, decreased heat shock protein (HSP) 70 and 90 expression, activated caspase-9, caspase-3 and induced poly(ADP-ribose) polymerase (PARP) cleavage. We have also determined that HSP70 and 90 inhibitions correlated with Bengalin induced antiproliferation, caspase-3 upregulation, apoptogenesis and increased DNA fragmentation. These results hypothesize that Bengalin might provide a putative molecular mechanism for their anticancer effect on human leukemic cells which might be mediated by mitochondrial death cascade. Inhibition of HSPs might also play a crucial role in induction of apoptosis.

Dietary supplies of iodine & thiocyanate in the aetiology of endemic goitre in Imphal East district of Manipur, north east India

BACKGROUND & OBJECTIVE

The present investigation was undertaken to study the iodine nutritional status of school children of Imphal east district in Manipur where endemic goitre persists during post-salt iodization phase along with the investigation of the factors responsible for the occurrence of goitre endemicity.

METHODS

A total of 1,286 children (6-12 yr) were clinically examined for goitre from study areas of Imphal east district. A total of 160 urine samples were collected and analyzed to measure urinary iodine and thiocyanate levels. Iodine content was measured in 140 salt samples and 16 drinking water samples.

RESULTS

Overall goitre prevalence was about 30 per cent (grade 1-24.7%; grade 2-5.3%) and median urinary iodine level was 17.25 microg/dl. The mean urinary thiocyanate level was 1.073 +/- 0.39 mg/dl. Iodine/thiocyanate ratio (microg/mg) was in the ranges from 15.65 to 22.34. The mean iodine content in drinking water samples was 2.92 +/- 1.75 microg/l and 97.8 per cent of edible salts had iodine level above 15 ppm at the consumption point.

INTERPRETATION & CONCLUSION

Our findings showed that in spite of no biochemical iodine deficiency, iodine deficiency disorders (IDD) is a serious public health problem in Imphal east district of Manipur. The consumption pattern of certain plant foods containing thiocyanate (or its precursors) was relatively high that interfere with thyroid hormone synthesis resulting in the excretion of more iodine. Thus, the existing dietary supplies of thiocyanate in relation to iodine may be a possible aetiological factor for the persistence of endemic goitre in the study region during post salt iodization period.

A crystalline compound (BM-ANF1) from the Indian toad (Bufo melanostictus, Schneider) skin extract, induced antiproliferation and apoptosis in leukemic and hepatoma cell line involving cell cycle proteins

In our earlier communication, it was reported that Indian toad (Bufo melanostictus) skin extract (TSE) possesses antiproliferative and apoptogenic activity in U937 and K562 cells [Giri et al., 2006. Antiproliferative, cytotoxic and apoptogenic activity of Indian toad (Bufo melanostictus, Schneider) skin extract in U937 and K562 cells. Toxicon 48 (4), 388-400]. In the present study, a compound (BM-ANF1) has been isolated from the TSE by alumina gel column chromatography, crystallized and evaluated for its antiproliferative and apoptogenic activity in U937, K562 and HepG2 cells. BM-ANF1 produced dose-dependent inhibition of U937, K562 and HepG2 cell growth. The antiproliferative activity was reflected by the MTT assay and demonstrated by the reduced expression of proliferative cell nuclear antigen (PCNA). Flow-cytometric analysis showed that BM-ANF1 arrested the cell cycle at G1 phase and enhanced annexin-V binding in U937 and K562 cells. Scanning electron microscopic and fluorescent microscopic analysis of U937 and K562 cells revealed the apoptogenic nature of the compound. Alkaline comet assay showed that BM-ANF1 produced DNA fragmentation. The dose-dependent expression of caspase 3 indicated that the apoptogenic properties of BM-ANF1 were mediated through the activation of downstream effector nucleases in the cancer cells. The increased expression of p53 and moderate expression of p21(Cip1)/p27(Kip1) due to BM-ANF1 treatment in HepG2 cells supported that the apoptogenic activity of BM-ANF1 was mediated through p53 tumor-suppressor gene expression followed by the expression of p21(Cip1) and p27(Kip1) and it was likely to be linked with cell cycle arrest at G1 phase in cancer cells. From the present study, it may be suggested that the crystalline compound, BM-ANF1, was antiproliferative and apoptogenic in human leukemic and hepatoma cells.

Bioactive molecules from amphibian skin: their biological activities with reference to therapeutic potentials for possible drug development

The amphibian skin contains various bioactive molecules (peptides, proteins, steroids, alkaloids, opiods) that possess potent therapeutic activities like antibacterial, antifungal, antiprotozoal, antidiabetic, antineoplastic, analgesic and sleep inducing properties. Research on amphibian skin derived biomolecules can provide potential clue towards newer drug development to combat various pathophysiological conditions. An overview on the bioactive molecules of various amphibian skins has been discussed.

Indian black scorpion (Heterometrus bengalensis Koch) venom induced antiproliferative and apoptogenic activity against human leukemic cell lines U937 and K562

Venoms are rich source of several bioactive compounds that possess therapeutic potentials. The different constituents of scorpion venom can modulate cell proliferation, cell growth and cell cycle. In the present communication, the cytotoxic activity of Indian black scorpion (Heterometrus bengalensis) venom was explored on human leukemic U937 and K562 cells. Scorpion venom induced U937 and K562 cell growth inhibition and the IC(50) value calculated to be 41.5 microg/ml (U937) and 88.3 microg/ml (K562). The scorpion venom showed characteristic features of apoptosis such as membrane blebbing, chromatin condensation and DNA degradation in both the cells as evidenced by confocal, fluorescence, scanning electron microscopy. Scorpion venom (IC(50) dose, 48 h) induced DNA fragmentation as evidenced by comet formation. Flow-cytometric assay revealed a significant amount of apoptotic cells (early and late) due to scorpion venom treatment. The venom induced cell cycle arrest was observed with maximum cell accumulation at sub-G(1) phase. Thus, the Indian scorpion (H. bengalensis) venom possessed antiproliferative, cytotoxic and apoptogenic activity against human leukemic cells.

Venom of Indian monocellate cobra and Russell's viper show anticancer activity in experimental models

Indian monocellate cobra (Naja kaouthia) and Russell's viper (Vipera russelli) are common snakes of the East Indian sub-peninsula. The anticarcinogenic activities of their crude venoms were studied on carcinoma, sarcoma and leukemia models. Sub-lethal doses of venoms showed cytotoxicity on Ehrlich ascites carcinoma (EAC) cells in vivo. The venoms increased lifespan of EAC mice and strengthened the impaired host antioxidant system. Sarcoma formation in mice (3-methylcholanthrene induced) after venom treatment was significantly less (p < 0.005). Histopathological examination of tumors showed tissue necrosis. The venoms displayed potent cytotoxic and apoptogenic effect on human leukemic cells (U937/K562). The venoms reduced cell proliferation rate (p < 0.005) and produced morphological alterations indicative of apoptosis induction. Different degree and nature of anticarcinogenic property of cobra and viper venoms may be attributed to the difference in their constituents.

A heat stable protein toxin (drCT-I) from the Indian Viper (Daboia russelli russelli) venom having antiproliferative, cytotoxic and apoptotic activities

A heat stable 7.2kDa protein toxin (drCT-I) has been purified and crystallized from Indian Daboia russelli russelli venom (Roy Choudhury et al., 2006. Acta Cryst. F Struct Biol Cryst Commun, 62(Pt. 3), 292). The N-terminal (first 20) amino acid sequence of drCT-I was LKCNKLVPLFYKTCPAGKNL, which showed sequence homology to cytotoxins isolated from Naja venom. drCT-I has been evaluated for anticancer activity against EAC cells in vivo and human leukemic cells (U937, K562) in vitro. drCT-I (125 microg/kg, i.p/day for 10 days) significantly decreased EAC cell count, cell viability (p<0.001) and significantly increased the survival time of tumour bearing mice (T/C% 178.64, p<0.01) in comparison to untreated tumour bearing control. drCT-I, produced dose and time-dependent inhibition of U937 and K562 cell growth and had an IC50 of 8.9 and 6.7 microg/ml respectively after 24h treatment. The reduced MTT values after drCT-I treatment indicated its cytotoxic nature, which supported its antiproliferative action. Scanning electron microscopy and confocal microscopy in U937 and K562 cells after drCT-I treatment indicated certain features of apoptosis such as membrane blebbing, perforations, nuclear fragmentation. The induction of apoptosis was further confirmed by phosphatidylserine externalization observed using annexinV-FITC/PI staining and flow cytometric analysis. drCT-I brought about apoptosis by G1 phase arrest of the cell cycle. The effect of drCT-I on normal human peripheral blood mononuclear cell (PBMNC) viability and cytotoxicity was studied in culture and was found to be lower than that on U937 and K562 cells. Thus both in vivo and in vitro experimental results suggested that drCT-I possessed anticancer potential.

Antiproliferative, cytotoxic and apoptogenic activity of Indian toad (Bufo melanostictus, Schneider) skin extract on U937 and K562 cells

The antiproliferative, cytotoxic and apoptogenic activities of Bufo melanostictus (Indian common toad) skin extract (TSE) on U937 and K562 leukemic cell line has been investigated. TSE significantly (P<0.001) reduced the time-dependent cell proliferation and decreased MTT values in U937 and K562 cells. TSE (IC50 doses) suppressed the proliferating cell nuclear antigen expression in both the cells. It was demonstrated that, TSE (IC50 doses) primarily arrested the U937 and K562 cells at G1 phase of the cell cycle. Confocal microscopy showed the altered fragmented nuclei and apoptotic bodies formation in TSE (IC50 doses) treated U937 and K562 cells. Membrane blebbing, cell surface shrinkage and perforation were observed through scanning electron microscope. TSE-induced DNA fragmentation in U937 and K562 cells was reflected in single-cell gel electrophoresis. TSE significantly (P<0.001) increase the length-width ratio of DNA mass as compared to control in comet assay. The flow cytometric analysis of annexin-V binding to the cancer cells further supported the apoptotogenic activity of TSE. The effect of TSE on normal human peripheral blood mononuclear cells viability and cytotoxicity was studied in culture and found to be less cytotoxic than on the U937 and K562 cells. The findings from the present study suggested that TSE might possess potent antineoplastic agent having antiproliferative, cytotoxic and apoptogenic activity against U937 and K562 myeloid leukemic cells.

PCR detection of Giardia lamblia in stool: targeting intergenic spacer region of multicopy rRNA gene

A PCR based detection that amplifies the 552-bp intergenic spacer (IGS) region of multicopy rRNA gene of Giardia lamblia and 320-bp internal sequences to first PCR product has been used in diagnosis of giardiasis in stool sample. The primers were found highly specific to Giardia spp. only, because no amplification was observed with DNAs from other enteric pathogens like Escherichia coli, Shigella dysenteriae and Entamoeba histolytica. The test could detect even less than 2 pg of genomic DNA from Giardia trophozoites. In direct diagnosis of Giardia lamblia in stool samples, it was observed that PCR amplification of IGS followed by nested PCR could enhance the sensitivity and specificity of the tests manifold and the system was able to detect as low as 10 parasites in 100 microl of stool. The comparative evaluation of the present system with conventional microscopy, CIEP and ELISA in the diagnosis of giardiasis from diarrhoeic stool samples and control subjects demonstrated a 100% correlation among nested PCR, microscopic examination and ELISA in patients suggestive of giardiasis (Group I) and control subjects (Group II). In Group I cases (patients suffering from other than giardiasis), CIEP, ELISA and nested PCR showed better results than microscopic examination. However, among them, PCR was found most sensitive and specific because 20% positivity was noticed by PCR whereas CIEP and ELISA showed only 7.14% and 12.85%, respectively. Break-up results showed that all the samples which were positive by CIEP or ELISA, also found positive by PCR. The present observation clearly suggests the use of PCR that amplifies the intergenic spacer region of multicopy rRNA gene of Giardia lamblia followed by nested PCR for routine, quick and reliable detection of Giardia lamblia in stool samples.

Molecular mechanisms of pathogenesis in amebiasis

Though both Entamoeba histolytica and E. dispar colonize the human gut, only the former is capable of invading tissues and causing disease. Although the biology of the parasite and the mechanism of pathogenesis have been intensively studied, there is a lack of consensus about the molecules of E. histolytica that actively participate in pathogenesis. This article reviews some key molecules involved. Ga1NAc-inhibitable adhesin is a membrane-associated glycoprotein nature, consisting of heavy and light subunits; each of these is encoded by multiple genes. The heavy subunit is useful in differentiating E. histolytica from E. dispar. Three structurally similar isoforms of amebapore, A, B and C, have been identified in E. histolytica but C is absent in E. dispar. Proteolytic enzymes such as collagenase and cysteine proteinases and cytolytic enzymes like phospholipase A are important. Collagenase activity is mainly accumulated in electron-dense granules. Cysteine proteinase is encoded by six genes, of which EhCP5 is exclusively present in E. histolytica.

Antigens of diagnostic and prophylactic importance inEntamoeba histolytica

Amoebiasis, caused by an enteric protozoanEntamoeba histolytica, is one of the major parasitic diseases of mankind. Current estimate suggests that the parasite infects about 10% of the world population at any given time. There is an urgent need to characterize the antigenic molecules ofE. histolytica, and find out antigens which have both immunodiagnostic and prophylactic potential against amoebiasis. The results of somatic antigen analysis, using sera from immune or infected individuals, indicated that the wholeE. histolytica trophozoites, are highly complex and heterogeneous in nature and both immunodiagnostic and immuno prophylaxis activity remain mainly in a surface associated 29 kDa glycoprotein ofE. histolytica. Future studies at molecular level particularly, genes responsible for expression of this protein, their homology with other proteins and structure analysis will give better understanding about this polypeptide. Studies on excretory secretory antigens, clearly demonstrated thatE. histolytica like many organisms, also liberates certain antigenic moieties into the culture medium during in vitro cultivation and this antigen has similar diagnostic values like the conventional somatic antigens. It is important that the ESA should be prepared from the supernatant after collecting the cell and use for immunodiagnosis of amoebiasis. This is an additional source of antigen which will help in carrying out more tests using the same reagents. Further studies are needed to clarify the location of these molecules on the parasite, along with detailed biochemical and immunological characterization and their relation with the pathogenesis.

Acute secretory travellers' diarrhoea caused by Vibrio cholerae non-01 which does not produce cholera-like or heat-stable enterotoxins

An Australian tourist suffering from severe acute watery diarrhoea and dehydration due to Vibrio cholerae non-01 was studied. The V. cholerae strain isolated from the patient belonged to serovar 05. The organism did not produce any of the conventional enterotoxins including cholera-toxin (CT) or heat-stable toxins (NAG-ST) that are known to be associated with intestinal secretion. This report suggests that toxin(s) other than CT-like or NAG-ST may be involved in the pathogenesis of diarrhoea by some V. cholerae non-01 strains.

Efficacy of norfloxacin for shigellosis: a double-blind randomised clinical trial

In a double-blind, randomised, clinical trial on 122 adults with acute Shigella dysentery, 60 patients were treated with norfloxacin and 62 with nalidixic acid. Of these, 32 patients in the norfloxacin group and 28 patients in the nalidixic acid group had Shigella in their stool. Patients of the two treatment groups were clinically comparable on admission. No significant differences in clinical responses were observed in the two groups among the Shigella-positive cases, Shigella-negative cases and among the total cases. All isolates of Shigella were susceptible to norfloxacin, whereas 13.8% of the strains were resistant to nalidixic acid.