An assessment of metal absorption competence of indigenous metal tolerant bacterial species- an in-vitro study.

Heavy metals pose a serious global threat to the environment. Hence, removing hazardous metals from soil samples has become complicated over the past few years. The current work looked into the remediation of heavy metals from aqueous solutions using a bacterial community and a unique bacterium obtained from metal-contaminated soil. In this investigation, the isolates of Bacillus anthracis A1-7, Bacillus. thuringiensis A1-3, Bacillus. cereus A1-5, and Pseudomonas aeruginosa A-33 actively demonstrated metal tolerances to various tested metals. Furthermore, an in-vitro biosorption study was performed under ideal concentration. The bacterial consortia achieved the highest biosorption effectiveness for Cu & Zn, 92.7% and 90.3%, respectively. When compared with a single bacterium, the group exhibited inferior Pb biosorption (86%). Since then, P. aeruginosa A33 has had the highest Pb biosorption. Finally, a bacterial consortium has devised an intriguing strategy for eliminating Cu and Pb from the polluted medium. P. aeruginosa A33 was found to be a mighty microbe that extracts Zn from polluted water. This metal-tolerant bacterium also exhibited specific proportions of selective commercially available antibiotics, which were analyzed using the Multiple Antibiotic Resistance (MAR) Index. In conclusion, these findings indicated that bacterial consortia composed of four bacterial isolates can remove metals from a metal-polluted medium.

Antidengue potential of leaf extracts of Pavetta tomentosa and Tarenna asiatica (Rubiaceae) against dengue virus and its vector Aedes aegypti (Diptera: Culicidae).

The aim of the present study was to screen the anti-dengue potential of crude leaf extracts of two plants from Pavetta tomentosa and Tarenna asiatica. For larvicidal assay, the acetone extract of both plants showed maximum effects, with the least LC50 and LC90 values (P. tomentosa (5.968 and 7.493 µg/ml) and T. asiatica (1.288 and 1.992 µg/ml)) and the same extract of both plants exhibited better pupicidal potency. The adulticidal activity of both plants (0-60 min interval periods) recorded best results in acetone extracts and the LC50 and LC90 values were recorded as P. tomentosa (32.105 and 41.001 µg/ml) and T. asiatica (09.012 and 11.854 µg/ml). Among the two plants P. tomentosa acetone leaf extract have good antiviral property against Dengue viral cell line. In addition, the phytochemical nature of the plant reveals the presence of saponins, flavonoids and alkaloids in all the tested extracts of both plants. GC-MS analysis revealed Hexanedioic acid, Bis(2-Ethylhexyl) Ester (22.54) and 2,6,10,14,18,22- Tetracosahexane, 2,6,10, 15, 19,15,19,23- Hexamethyl-(ALL-E)- (25.33) identified as two major phytoconstitutents in P. tomentosa and Tetracontane (23.580) is a major compound identified from T. asiatica acetone extracts. The functional groups of chemical compounds (aromatis, alkanes, alkyls and carboxylic acids) from P. tomentosa and T. asiatica were analyzed by FT-IR spectrum.

Growth optimization, free radical scavenging and antibacterial potential of Chlorella sp. SRD3 extracts against clinical isolates.

AIM: The aim of present work was to explore the potential of Chlorella sp. SRD3 extracts for antioxidant and antibacterial activity along with the evaluation of minimum inhibitory concentration (MIC) and haemolytic activity to detect RBC cell damage. METHODS AND RESULTS: Screening and isolation of microalgae was performed using bold basal medium under normal illuminance (at 27°C) and microscopic observation. Growth of the microalgae was optimized using a different medium and light source. The isolated microalgae incubated under fluorescent light when cultured in F/2 medium showed a highest dry biomass yield of 3·77 ± 0·1 g l-1 , when compared to the growth under direct sunlight (2·74 ± 0·07 g dwt l-1 ). The quantitative analysis of extracts revealed higher phenols, flavonoids and proanthocyanidins in ethyl acetate and hexane extracts followed by methanol. The antioxidant activity of extracts was tested against 1-diphenyl-2-picrylhydrazyl and ABTS radical, its reducing power assay was performed. From antibacterial activity, the two extracts showed better inhibition against Gram-negative bacteria. Also, they resulted in very low MIC values with effective activity against pathogens. In haemolytic activity, no haemolysis occurred, when the concentration (µg ml-1 ) was below 64 for methanol and 32 for ethyl acetate extract. In addition, Chlorella sp. extracts were characterized by GC-MS analysis to detect the major compounds. CONCLUSION: The polar extracts revealed satisfactory results against the clinical isolates and the compounds responsible were reflected in the GC-MS spectrum. SIGNIFICANCE AND IMPACT OF THE STUDY: The present study revealed significant biological potentials of the green alga, Chlorella sp. such as antioxidant, antibacterial and hemolytic activities. Therefore, this vital source might serve as a cost-effective, alternative choice to the pharmaceutical and food industries in the near future.

Aortic stenosis - pathogenesis, prediction of progression, and percutaneous intervention.

Aortic stenosis is common and an important cause of morbidity and mortality. Prevalence will increase significantly in forthcoming decades as a function of the ageing population; treatment by means of surgery or percutaneous intervention is expensive. Epidemiological, mechanistic and interventional studies are therefore vital to determine optimal and innovative treatments and their funding. Recent studies suggest that aortic stenosis is not a passive degenerative disease, but an active process involving several pathways, including lipid infiltration, chronic inflammation, fibrosis formation, osteoblast activation, and active valve mineralisation. Despite similarities with atherosclerosis, randomised statin trials proved negative in aortic stenosis, underlining the need to explore alternative pathophysiological pathways. Left ventricular hypertrophy in response to pressure overload in aortic stenosis is initially adaptive but ultimately decompensates, leading to progressive left ventricular impairment, symptoms and adverse cardiovascular events. This transition is driven primarily by myocyte death and myocardial fibrosis. Cardiac magnetic resonance imaging can visualise and quantify myocardial fibrosis and may provide additional and independent prognostic information in aortic stenosis. Moreover, new markers of fibrosis utilising novel imaging techniques are rapidly emerging. Transcatheter aortic valve implantation is a disruptive technology that has transformed the management of aortic stenosis, and encouraged a wider multidisciplinary approach to the management of valvular heart disease. While originally applied in older, high-risk patients, recent trends for its use in intermediate risk patients have been supported by the findings of key clinical trials in 2016.

Spectral characterization and antibacterial activity of an isolated compound from Memecylon edule leaves.

Memecylon edule Roxb. (Melastamataceae family) is a small evergreen tree reported as having ethnobotanical and pharmacological properties. The present study was aimed to investigate the spectral characterization and antibacterial activity of isolated pure compound (3ß-hydroxyurs-12-en-28-oic acid (ursolic acid)) from Memecylon edule leaves by performing bioassay guided isolation method. The structure derivation of isolated compound was done by different spectral studies like UV, FT-IR, LC-MS, CHNS analysis, 1D (1H, 13C and DEPT-135) and 2D-NMR (HSQC and HMBC), respectively. About 99.29% purity of the compound was found in LC analysis. 1H NMR spectrum results of compound shown 48 protons appear at different shielded region and most of the protons were present in aliphatic region. Whereas, 13C NMR spectral data resulted seven methyl carbons (CH3), nine methylene carbons (CH2), seven methine carbons (CH) and six non-hydrogenated carbons (C) which are characteristic of pentacyclic triterpene. The isolated pure compound was tested for its antibacterial properties against targeted human pathogens by performing agar well diffusion, MIC and MBC assays and the result exhibits better growth inhibitory effects against S. epidermidis and S. pneumoniae, with the MIC values of 1.56 and 3.15µg/ml. The outcome of this study suggests that the bioactive compound is used for development of plant based drugs in pharmaceutical industry for combating microbial mediated diseases.

In vivo transplantation of fetal human gut-derived enteric neural crest cells.

The prospect of using neural cell replacement for the treatment of severe enteric neuropathies has seen significant progress in the last decade. The ability to harvest and transplant enteric neural crest cells (ENCCs) that functionally integrate within recipient intestine has recently been confirmed by in vivo murine studies. Although similar cells can be harvested from human fetal and postnatal gut, no studies have as yet verified their functional viability upon in vivo transplantation. We sought to determine whether ENCCs harvested from human fetal bowel are capable of engraftment and functional integration within recipient intestine following in vivo transplantation into postnatal murine colon. Enteric neural crest cells selected and harvested from fetal human gut using the neurotrophin receptor p75NTR were lentivirally labeled with either GFP or calcium-sensitive GCaMP and transplanted into the hindgut of Rag2- /γc- /C5- -immunodeficient mice at postnatal day 21. Transplanted intestines were assessed immunohistochemically for engraftment and differentiation of donor cells. Functional viability and integration with host neuromusculature was assessed using calcium imaging. Transplanted human fetal gut-derived ENCC showed engraftment within the recipient postnatal colon in 8/15 mice (53.3%). At 4 weeks posttransplantation, donor cells had spread from the site of transplantation and extended projections over distances of 1.2 ± 0.6 mm (n = 5), and differentiated into enteric nervous system (ENS) appropriate neurons and glia. These cells formed branching networks located with the myenteric plexus. Calcium transients (change in intensity F/F0 = 1.25 ± 0.03; 15 cells) were recorded in transplanted cells upon stimulation of the recipient endogenous ENS demonstrating their viability and establishment of functional connections.

Ipomoea batatas (Convolvulaceae)-mediated synthesis of silver nanoparticles for controlling mosquito vectors of Aedes albopictus, Anopheles stephensi, and Culex quinquefasciatus (Diptera:Culicidae).

We proposed an effective and eco-friendly control of dengue, malaria, and filariasis-causing vectors. We tested Ipomoea batatas leaves-mediated silver nanoparticles (AgNPs) against first to fourth instar larvae and adults of Aedes albopictus, Anopheles stephensi, and Culex quinquefasciatus at different concentrations. The synthesized AgNPs showed broad spectrum of larvicidal and adulticidal effects after 48 h of exposure. The characterization of synthesized AgNPs was done using various spectral and microscopy analyses. The maximum efficacy was observed in synthesized AgNPs against the adult of Ae. albopictus with the LC50 and LC90 values were 10.069 and 15.657 µg/mL, respectively, followed by others.

Phytoremediation potential of some agricultural plants on heavy metal contaminated mine waste soils, salem district, tamilnadu.

The Pot culture experiment performed for phytoextraction potential of selected agricultural plants [millet (Eleusine coracana), mustard (Brassica juncea), jowar (Sorghum bicolor), black gram (Vigna mungo), pumpkin (Telfairia occidentalis)] grown in metal contaminated soils around the Salem region, Tamilnadu, India. Physiochemical characterization of soils, reported as low to medium level of N, P, K was found in test soils. The Cr content higher in mine soils than control and the values are 0.176 mg/L in Dalmia soil and 0.049 mg/L in Burn & Co soil. The germination rate low in mine soil than control soils (25 to 85%). The content of chlorophyll, carotenoid, carbohydrate and protein decreased in mine soils than control. The morphological parameters and biomass values decreased in experimental plants due to metal accumulation. Proline content increased in test plants and ranged from 0.113 mg g(-1) to 0.858 mg g(-1) which indicate the stress condition due to toxicity of metals. Sorghum and black gram plants reported as metal tolerant capacity. Among the plants, Sorghum produced good results (both biomass and biochemical parameters) which equal to control plant and suggests Sorghum plant is an ideal for remediation of metal contaminated soils.

Annona muricata leaf extract-mediated silver nanoparticles synthesis and its larvicidal potential against dengue, malaria and filariasis vector.

Mosquitoes transmit several diseases which cause millions of deaths every year. The use of synthetic insecticides to control mosquitoes caused diverse effects to the environment, mammals, and high manufacturing cost. The present study was aimed to test the larvicidal activity of green synthesized silver nanoparticles using Annona muricata plant leaf extract against third instar larvae of three medically important mosquitoes, i.e., Aedes aegypti, Anopheles stephensi, and Culex quinquefasciatus. The different concentrations of green synthesized Ag Nanoparticles (AgNPs; 6, 12, 18, 24, 30 µg mL(-1)) and aqueous crude leaf extract (30, 60, 90, 120, 150 µg mL(-1)) were tested against the larvae for 24 h. Significant larval mortality was observed after the treatment of A. muricata for all mosquitoes with lowest LC50 and LC90 values, viz., A. aegypti (LC50 and LC90 values of 12.58 and 26.46 µg mL(-1)), A. stephensi (LC50 and LC90 values of 15.28 and 31.91 µg mL(-1)) and C. quinquefasciatus (LC50 and LC90 values of 18.77 and 35.72 µg mL(-1)), respectively. The synthesized AgNPs from A. muricata were highly toxic than aqueous crude extract. The nanoparticle characterization was done using spectral and microscopic analysis, namely UV-visible spectroscopy which showed a sharp peak at 420 nm of aqueous medium containing AgNPs, X-ray diffraction (XRD) analysis revealed the average crystalline size of synthesized AgNPs (approximately 45 nm), and Fourier transform infrared spectroscopy (FTIR) study exhibited prominent peaks 3381.28, 2921.03, 1640.17, 1384.58, 1075.83, and 610.77 cm(-1). Particle size analysis (PSA) showed the size and distribution of AgNPs (103 nm); field emission scanning electron microscopy (FE-SEM) and high-resolution transmission electron microscopy (HR-TEM) analysis showed a spherical shape, size range from 20 to 53 nm; and energy-dispersive X-ray spectroscopy (EDX) reflects the chemical composition of synthesized AgNPs. Heat stability of the AgNPs was confirmed between the temperatures 20 to 70 °C. The result suggests that green synthesized AgNPs from A. muricata has the potential to be used as a low-cost and eco-friendly approach for the control of selected mosquitoes.

Lentiviral labeling of mouse and human enteric nervous system stem cells for regenerative medicine studies.

BACKGROUND: Reliable methods of labeling human enteric nervous system (ENS) stem cells for use in novel cell replacement therapies for enteric neuropathies are lacking. Here, we explore the possibility of using lentiviral vectors expressing fluorescent reporter genes to transduce, label, and trace mouse and human ENS stem cells following transplantation into mouse gut. METHODS: Enteric nervous system precursors, including ENS stem cells, were isolated from enzymatically dissociated mouse and human gut tissues. Lentivirus containing eGFP or mCherry fluorescent reporter genes was added to gut cell cultures at a multiplicity of infection of 2-5. After fluorescence activated cell sorting for eGFP and subsequent analysis with markers of proliferation and cell phenotype, transduced mouse and human cells were transplanted into the gut of C57BL/6 and immune deficient Rag2-/gamma chain-/C5 mice, respectively and analyzed up to 60 days later. KEY RESULTS: Mouse and human transduced cells survived in vitro, maintained intense eGFP expression, proliferated as shown by BrdU incorporation, and formed characteristic neurospheres. When transplanted into mouse gut in vivo and analyzed up to 2 months later, transduced mouse and human cells survived, strongly expressed eGFP and integrated into endogenous ENS networks. CONCLUSIONS & INFERENCES: Lentiviral vectors expressing fluorescent reporter genes enable efficient, stable, long-term labeling of ENS stem cells when transplanted into in vivo mouse gut. This lentiviral approach not only addresses the need for a reliable fluorescent marker of human ENS stem cells for preclinical studies, but also raises the possibility of using lentiviruses for other applications, such as gene therapy.

Phyllanthus wightianus Müll. Arg.: a potential source for natural antimicrobial agents.

Phyllanthus wightianus belongs to Euphorbiaceae family having ethnobotanical importance. The present study deals with validating the antimicrobial potential of solvent leaf extracts of P. wightianus. 11 human bacterial pathogens (Bacillus subtilis, Streptococcus pneumoniae, Staphylococcus epidermidis, Proteus vulgaris, Pseudomonas aeruginosa, Klebsiella pneumoniae, Salmonella typhimurium, Escherichia coli, Shigella flexneri, Proteus vulgaris, and Serratia marcescens) and 4 fungal pathogens (Candida albicans, Cryptococcus neoformans, Mucor racemosus, and Aspergillus niger) were also challenged with solvent leaf extracts usingagar well and disc diffusion methods. Further, identification of the active component present in the bioactive extract was done using GC-MS analysis. Results show that all extracts exhibited broad spectrum (6-29 mm) of antibacterial activity on most of the tested organisms. The results highlight the fact that the well in agar method was more effective than disc diffusion method. Significant antimicrobial activity was detected in methanol extract against S. pneumoniae (29 mm) with MIC and MBC values of 15.62 µg/mL. GC-MS analysis revealed that 29 bioactive constituents were present in methanolic extract of P. wightianus, of which 9,12-octadecaenioic acid (peak area 22.82%; RT-23.97) and N-hexadecanoic acid (peak area 21.55% RT-21.796) are the major compounds. The findings of this study show that P. wightianus extracts may be used as an anti-infective agent in folklore medicine.

Immunohistochemical and ultrastructural features of congenital melanocytic naevus cells support a stem-cell phenotype.

BACKGROUND: Multiple congenital melanocytic naevi (CMN) in one individual are caused by somatic mosaicism for NRAS mutations; however, the lineage of the mutated cells remains uncertain. OBJECTIVES: To test the hypothesis that CMN may be derived from cutaneous stem cells. METHODS: Sixty-six CMN samples from 44 patients were stained for immunohistochemical (IHC) markers of melanocytic differentiation (TYR, TRP1, TRP2, LEF1, MITF, cKit), pluripotency (nestin, fascin, CD133, CD20, CD34), monocyte/macrophage lineage (CD68, CD163, CD14), proliferation (Ki67) and MTOR/Wnt-signalling pathway activation (pS6, ß-catenin). Semiquantitative scoring compared samples with naevus cell nesting (group 1) with those with only diffuse dermal infiltration (group 2). Transmission electron microscopy (TEM) was performed on 10 samples. RESULTS: A normal melanocyte population was seen overlying many dermal CMN. Group 1 samples were significantly more likely to express melanocytic differentiation markers than group 2, and expression decreased significantly with depth. Expression of these markers was correlated with each other, and with nestin and fascin. CD20 staining was positive in a substantial proportion and was stronger superficially. Expression of ß-catenin and pS6 was almost universal. Some samples expressed monocyte/macrophage markers. TEM revealed variable naevus cell morphology, striking macromelanosomes, double cilia and microvilli. CONCLUSIONS: Congenital melanocytic naevi development frequently coexists with normal overlying melanocyte development, leading us to hypothesize that in these cases CMN are likely to develop from a cell present in the skin independent of, or remaining after, normal melanocytic migration. IHC and TEM findings are compatible with CMN cells being of cutaneous stem-cell origin, capable of some degree of melanocytic differentiation superficially.

Psychiatrists and neuroscientists of Indian origin in Canada: Glimpses.

Psychiatrists of Indian origin are popular in Canada, being firmly rooted in the Canadian mental health system, and they have been making considerable contributions internationally. The Indian Psychiatric Society has long been collaborating with and inviting contributions from overseas Indian psychiatrists, particularly those in academics, and this collaboration has fructified well. There are several different challenges these psychiatrists have had to face in their own specialty work, with having to adjust to a new culture, new ways of living, and new ways of work. Our colleagues of Indian origin have demonstrated excellence in almost all fields of mental health and neurosciences. There are many popular teachers, outstanding researchers, and psychiatrists in community practice and community development. The Early Psychosis Program, Mood and Anxiety Program, Perinatal Psychiatry, Women's Mental Health, and Postpartum Mental Health are some of their key areas of research. Our basic scientists are involved in experimental design, neurochemistry, imaging, and genetics, where they have made their mark with acclaim. This article highlights some of the achievements of a few members and is by no means completely representative of the entire work that psychiatrists of Indian origin are doing in Canada, providing readers with a glimpse of our labors away from home.

Anti-bacterial activity of Euphorbia fusiformis--a rare medicinal herb.

Euphorbia fusiformis Buch.-Ham. ex. D.Don (Euphorbiaceae) is a rare medicinal herb. Aqueous and organic solvent extracts of the leaves and rootstocks were investigated for anti-bacterial properties by using disc diffusion and well-in agar methods, against pathogenic strains of Gram positive (Bacillus subtilis and Staphylococcus aureus) and Gram negative bacteria (Escherichia coli, Klebsiella pneumoniae, Proteus vulgaris, Pseudomonas aeruginosa, Salmonella typhii A and Salmonella typhii B). The different extracts differed significantly in their anti-bacterial properties with the methanolic extract being very effective followed by acetone and chloroform extracts. Aqueous and ethanolic extract showed very least activity. The result highlights that rootstock extracts had good anti-bacterial properties than leaf extracts. The results of this study support the use of this plant in traditional medicine to treat fever, wound infections and intestinal disorders.

Antimicrobial studies on methanol extract of benincasa hispida cogn., fruit.

The methanol extract of wax gourd, the fruits of Benincasa hispida cogn.(Cucurbitaceae) was found to show no inhibition against three gram positive bacteria Staphylococcus aureus, Staphylococcus epidermidis, and Bacillus subtilis and three gram negative bacteria Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumonia by cup-plate method whereas antifungal studies showed significant inhibition against Candida albicans in the concentration of 30 mg/ml and there was no inhibition against Aspergillus niger.

Mouse Nov gene is expressed in hypaxial musculature and cranial structures derived from neural crest cells and placodes.

NOV is a member of an emerging family of proteins, the CCN family, implicated in the control of cell growth and differentiation. During mouse development Nov is expressed predominantly in the skeletal and visceral muscles and in the nervous system. Transcripts are first detected in muscle precursor cells from 10.0 dpc and later in the hypaxial muscles of the trunk and shoulder/hip, as well as in the muscles of the head and in the smooth muscle of major vessels. In the nervous system, Nov is observed in the somatic motor neurons of the spinal cord from 12.5 dpc and in cranial structures derived either from neural crest cells or placodes, including V, VII, VIII, and IX ganglia and olfactory neuroepithelia.

Multipotential progenitors of the mammalian enteric nervous system capable of colonising aganglionic bowel in organ culture.

The enteric nervous system of vertebrates is derived from neural crest cells that invade the gut wall and generate a highly organised network of enteric ganglia. Among the genes that play an important role in ENS development is c-Ret, mutations of which result in failure of formation of enteric ganglia (intestinal aganglionosis). To further understand the development of the mammalian ENS in general and the mechanism of action of the RET RTK in particular, we have developed and used an organotypic culture system of mouse fetal gut. At the stage of culture initiation, the gut is partially populated by undifferentiated ENS progenitors, but culture for several days results in extensive neuronal and glial differentiation. Using this organ culture system, we have compared the development of the ENS in wild-type and RET-deficient gut and showed that the aganglionic phenotype observed in vivo is consistently reproduced under the in vitro culture conditions. Microinjection of RET+ cells isolated from E11.5 mouse bowel into wild-type or RET-deficient aganglionic gut in organ culture, results in extensive repopulation of their wall by exogenously derived neurons and glia. Finally, using a similar approach, we demonstrate that single RET+ cells introduced into the wall of wild-type gut generate both cell lineages of the ENS, i.e. neurons and glia. Our data show the NC-derived RET+ population of fetal gut in mammalian embryos consists of multipotential progenitors capable of colonising efficiently both wild-type and RET-deficient aganglionic bowel in organ culture.

A PCR-based method for isolation of genomic DNA flanking a known DNA sequence.

We describe a simple PCR-based method for the isolation of genomic DNA that lies adjacent to a known DNA sequence. The method is based on the directional cloning of digested genomic DNA into the multiple cloning site of a pUC-based plasmid to generate a limited genomic library. The library is plated onto a number of selective LA plates which are incubated overnight, and recombinant plasmid DNA is then isolated from resistant colonies pooled from each plate. PCR amplification is performed on the pooled recombinant plasmid DNAs using primers specific for the pUC vector and the known genomic sequence. The combination of efficient directional cloning and bacterial transformation gives relative enrichment for the genomic sequence of interest and generates a simple DNA template, enabling easy amplification by PCR.