Pistia stratiotes (Jalkumbhi)

Pistia stratiotes (Family: Araceae) is commonly used in Ayurvedic medicine. This review article is a compilation of all the updated information on its phytochemical and pharmacological activities, which were performed by different methods. Studies indicate that P. stratiotes possesses diuretic, antidiabetic, antidermatophytic, antifungal, and antimicrobial properties. These results are very encouraging and indicate that this plant should be studied more extensively to confirm the reproducibility of these results and also to reveal other potential therapeutic effects, along with some “leads” with possible isolation of active biomoieties and their mechanism of action.

Studies on apoptotic changes in combined toxicity of citrinin and endosulfan in pregnant wistar rats and their fetuses

Background:

Citrinin (mycotoxin) and endosulfan (pesticide) both environmental contaminants easily enter the food chain and are caoomon causes of various toxicities.

Materials and Methods:

In the present investigation, citrinin (CIT) (10 mg/kg feed) and endosulfan (1 mg/kg body weight) were administered orally alone and in combination to pregnant Wistar rats from gestational day 6 to 20 to study their effect to cause apoptosis in the pregnant Wistar rats and their fetuses. Apoptosis was assessed in dams by agarose gel electrophoresis, flow cytometry and electron microscopy, while in the fetuses it was assessed by flow cytometry only.

Result:

Citrinin and endosulfan in the combination group caused apoptosis in an additive manner as there was increased number of apoptotic cells as compared to the individual toxin and control groups. The fetuses also showed increased number of apoptotic cells in the combination groups, which also indicated that both the toxins crossed the placental barrier.

Conclusion:

So it was concluded that apoptosis played a significant role in the pathogenesis of endosulfan and citrinin toxicity.

Laparoscopic adrenalectomy for co-secreting aldosterone and cortisol adenomas

There are few published data on aldosterone and cortisol co-secreting adrenal tumours. Failure to perform comprehensive preoperative endocrine investigations in patients with adrenal "incidentalomas" or in those thought to be secreting only one hormone may account for this. Clinically patients with such lesions may have evidence of hypertension and hypokalaemia with no features of cortisol excess. Preoperative diagnosis of such lesions with accurate endocrinological work up is essential to prevent adrenal insufficiency and haemodynamic crises following removal of such glands. We present a series of 4 patients with co-secreting tumours treated by laparoscopic adrenalectomy between September 2010 and March 2011. Our experience suggests that dual secretors are more common than originally thought. A high index of suspicion and adequate endocrine work up is paramount in diagnosing such tumours and in experienced hands, laparoscopic adrenalectomy with appropriate substitutive steroid cover is safe, feasible and curative for these functioning adrenal tumours.

Skeletal and dentoalveolar changes concurrent to use of Twin Block appliance in class II division I cases with a deficient mandible: a cephalometric study

Most of Class II malocclusions are due to underdeveloped mandible with increased overjet and overbite. Lack of incisal contact results in the extrusion of the upper and lower anterior dentoalveolar complex, which helps to lock the mandible and prevent its normal growth and development, and this abnormality, is exaggerated by soft tissue imbalance. The purpose of present study was to cephalometrically evaluate skeletal and dentoalveolar changes following the use of Twin-Block appliance in 10 growing children of age group 9-13 years (mean 11.1 year ± SD 1.37) of Class II division 1 malocclusion with a deficient mandible. Cephalometric pre- and post-functional treatment measurements (angular and linear) were done and statistically analyzed using student's paired t-test. The results of the present study showed that maxilla (SNA) was restricted sagittally (head gear effect) with marked maxillary dental retraction. Significant mandible sagittal advancement (SNB) with minimum dental protraction was observed with significant increase in the mandibular length. The maxillomandibular skeletal relation (ANB and WITS appraisal) reduced considerably which improved the profile and facial esthetics. Pronounced correction of overjet and overbite was seen. The present study concluded that Class II correction occurs by both skeletal and dentoalveolar changes.

The mRNA expression of DAP1 in human breast cancer: correlation with clinicopathological parameters

This pilot study is the first to focus on the potential role of death-associated protein 1 (DAP1) in human breast cancer.

MATERIALS AND METHODS

A total of 153 samples were studied. DAP1 transcription levels were determined using quantitative polymerase chain reaction (qPCR). Transcript levels within breast cancer specimens were compared to those of normal background tissues and correlated with clinicopathological data accumulated over a 10-year follow-up period.

RESULTS

The expression of DAP1 mRNA was demonstrated to decrease with increasing Nottingham Prognostic Index (NPI2 vs. NPI3, p=0.0026), and TNM stage (TNM1 vs. 4, p=0.0039). Lower DAP1 expression levels were significantly associated with local recurrence (p=0.02) and distant metastasis (p=0.001).

CONCLUSION

This study demonstrates an inverse association between DAP1 mRNA levels and tumour stage and clinical outcome in breast cancer; thus, providing evidence that DAP1 plays a pro-apoptotic role in human breast cancer. The relationship between oncogenesis and the autophagy pathway merits further investigation.

Noradrenaline vs. terlipressin in the treatment of hepatorenal syndrome: a randomized study

BACKGROUND & AIMS

Various vasoconstrictors are useful in the management of hepatorenal syndrome (HRS). Terlipressin is the drug of choice; however, it is expensive. In this study, we evaluated safety and efficacy of terlipressin and noradrenaline in the treatment of HRS.

METHODS

Forty-six patients with HRS type 1 were managed with terlipressin (group A, N=23) or noradrenaline (Group B, N=23) with albumin in a randomized controlled trial at a tertiary center.

RESULTS

HRS reversal could be achieved in 9 (39.1%) patients in group A and 10 (43.4%) patients in group B (p=0.764). Univariate analysis showed baseline Child Turcotte Pugh score (CTP), model of end stage liver disease (MELD), urine output on day 1(D1), albumin, and mean arterial pressure (MAP) were associated with response. However, on multivariate analysis only CTP score was associated with response. Fourteen patients in group A and 12 in group B died at day 15 (p>0.05). Noradrenaline was less expensive than terlipressin (p<0.05). No major adverse effects were seen.

CONCLUSIONS

The results of this randomized study suggest that noradrenaline is as safe and effective as terlipressin, but less expensive in the treatment of HRS and baseline CTP score is predictive of response.

Organism Isolation in Corneal Ulcer- Utility of Different Techniques

Introduction: Various techniques are available for isolation of microorganism in cases of microbial keratitis including conventional methods of scraping, re-scraping inoculation in different media and corneal biopsy. Methods: This was a cross sectional descriptive study conducted from February 2002 to July 2003. A total of 161 eyes of corneal ulcers were evaluated with scraping inoculation. Re-scraping and corneal biopsy were performed in those cases which did not grow any organism in the first scraping or which did not respond to initial treatment. Results: Microorganisms were isolated in 116 patients (72.04%) after first scraping. S pneumoniae was seen in 50(42%), Fusarium in 21(18%) and Aspergillus in 16(14%) cases. Re-scraping was done in 22 culture negative and non improving cases of which 14 (63.63%) showed isolation of organisms. After re-scraping, Fusarium and Aspergillus were isolated in four patients each (18% each) followed by S. pneumoniae in 3 (14%), S. aureus in 2 (9%), and Penicillium in 1(5%) case.Corneal biopsy was done in 10 cases with isolation of microbial agents in 7 (70%) with Aspergillus and S. aureus in three each, and S. epidermidis in 1(10%). Conclusions: Apart from conventional scraping, other isolation techniques should be considered in the treatment of non-responding and culture negative cases of corneal ulcers. Compared to bacteria, fungi are difficult to isolate in the first scraping and requires more frequent repeat scraping and corneal biopsy. Keywords: Corneal biopsy, corneal scraping, corneal ulcer, microbial keratitis, organismal isolation.

Nd: Yag laser treatment for sub-hyaloid hemorrhage in childhood acute leukemia

INTRODUCTION

Sub-hyaloid haemorrhage is common in acute leukemia.

OBJECTIVE

To investigate the effects of Nd: YAG Laser hyaloidotomy in 11 eyes of 8 patients with pre-macular haemorrhage in acute childhood leukemia.

MATERIALS AND METHODS

Premacular sub-hyaloid haemorrhage is one of the leading causes of visual disability in children with acute leukemia. Eleven eyes of 8 patients attending Kanti Children Hospital and BP Koirala Lions Centre for Ophthalmic Studies from January 2006 to July 2007 with premacular subhyaloid haemorrhage were included in the study and treated with Nd: YAG Laser. The haemorrhage originated from acute myeloid leukemia (AML) in 4 cases (6 eyes) and acute lymphoblastic leukemia (ALL) in 4 cases (5 eyes).

RESULTS

Drainage of premacular sub-hyaloid haemorrhage into the vitreous cavity within 3 months succeeded in 9 eyes out of 11 eyes treated. One eye had a dense clotted haemorrhage and the other had a re-bleed. Overall visual improvement was equal in both AML and ALL cases. No obvious epiretinal membrane, retinal breaks and tractional retinal detachment occurred in any eye.

CONCLUSION

Nd: Yag laser hyaloidotomy is a relatively safe, simple and alternative treatment for eyes with a dense premacular sub-hyaloid haemorrhage in acute childhood leukemia. The risks and benefits have to be weighed in randomized clinical trials to establish Nd: YAG hyaloidotomy treatment as a routine procedure in leukemic children.

The mRNA expression of DAP3 in human breast cancer: correlation with clinicopathological parameters

BACKGROUND

This pilot study is the first to focus on the potential role for death-associated protein 3 (DAP3) in human breast cancer.

MATERIALS AND METHODS

A total of 153 samples were studied. The levels of transcription of DAP3 were determined using quantitative polymerase chain reaction (qPCR). Transcript levels within breast cancer specimens were compared to those of normal background tissues and correlated with clinicopathological data accumulated by over a 10-year follow-up period.

RESULTS

The expression of DAP3 mRNA was demonstrated to decrease with increasing Nottingham Prognostic Index (NPI2 vs. 3, p=0.036), TNM stage (TNM1 vs. 3, p=0.07), and tumour grade (grade 1 vs. 3, p=0.08). Lower DAP3 expression levels were significantly associated with local recurrence (p=0.013), distant metastasis (p=0.0057) and mortality (p=0.019).

CONCLUSION

This study demonstrates an inverse association between DAP3 mRNA levels and tumour stage and clinical outcome in breast cancer, consistent with the pro-apoptosis function of DAP3. Further research is required in order to confirm our findings and clarify the mechanisms that regulate DAP3 expression in human breast cancer.

Organism isolation in corneal ulcer: utility of different techniques

INTRODUCTION

Various techniques are available for isolation of microorganism in cases of microbial keratitis including conventional methods of scraping, re-scraping inoculation in different media and corneal biopsy.

METHODS

This was a cross sectional descriptive study conducted from February 2002 to July 2003. A total of 161 eyes of corneal ulcers were evaluated with scraping inoculation. Re-scraping and corneal biopsy were performed in those cases which did not grow any organism in the first scraping or which did not respond to initial treatment.

RESULTS

Microorganisms were isolated in 116 patients (72.04%) after first scraping. S pneumoniae was seen in 50(42%), Fusarium in 21(18%) and Aspergillus in 16(14%) cases. Re-scraping was done in 22 culture negative and non improving cases of which 14 (63.63%) showed isolation of organisms. After re-scraping, Fusarium and Aspergillus were isolated in four patients each (18% each) followed by S. pneumoniae in 3 (14%), S. aureus in 2 (9%), and Penicillium in 1(5%) case. Corneal biopsy was done in 10 cases with isolation of microbial agents in 7 (70%) with Aspergillus and S. aureus in three each, and S. epidermidis in 1(10%).

CONCLUSIONS

Apart from conventional scraping, other isolation techniques should be considered in the treatment of non-responding and culture negative cases of corneal ulcers. Compared to bacteria, fungi are difficult to isolate in the first scraping and requires more frequent repeat scraping and corneal biopsy.

Lack of association between Glu298Asp polymorphism and coronary artery disease in North Indians

Nitric Oxide (NO) is an important molecule carrying number of different functions in humans. Published studies suggest that it may inhibit several key steps involved in the pathogenesis of atherosclerosis. Inhibition or reduction of NO due to Glu298Asp polymorphism may accelerate atherosclerosis. The aim of this study was to determine whether Glu298Asp polymorphism is implicated in the pathogenesis of coronary artery disease (CAD) among North Indian population from the state of Uttar Pradesh, India. We selected 253 CAD patients and 174 healthy, normotensive, non-diabetic controls, which were matched for gender and ethnicity. The Glu298Asp (rs1799983) variant was detected by genotyping subjects, using a polymerase chain reaction followed by restriction fragment length polymorphism. There was no significant difference found in the genotypic and allelic frequencies between patients and controls. Our study indicated that Glu298Asp polymorphism does not play any critical role in the pathogenesis of CAD, at least in North Indian population.

Phosphite utilization by the marine picocyanobacterium Prochlorococcus MIT9301

Primary productivity in the ocean's oligotrophic regions is often limited by phosphorus (P) availability. In low phosphate environments, the prevalence of many genes involved in P acquisition is elevated, suggesting that the ability to effectively access diverse P sources is advantageous for organisms inhabiting these regions. Prochlorococcus, the numerically dominant primary producer in the oligotrophic ocean, encodes high-affinity P transporters, P regulatory proteins and enzymes for organic phosphate utilization, but its ability to use reduced P compounds has not been previously demonstrated. Because Prochlorococcus strain MIT9301 encodes genes similar to phnY and phnZ, which constitute a novel marine bacterial 2-aminoethylphosphonate (2-AEPn) utilization pathway, it has been suggested that this organism might use 2-AEPn as an alternative P source. We show here that although MIT9301 was unable to use 2-AEPn as a sole P source under standard culture conditions, it was able to use phosphite. Phosphite utilization by MIT9301 appears to be mediated by an NAD-dependent phosphite dehydrogenase encoded by ptxD. We show that phosphite utilization genes are present in diverse marine microbes and that their abundance is higher in low-P waters. These results strongly suggest that phosphite represents a previously unrecognized component of the marine P cycle.

Evaluation of Fermentation Efficiency of Yeast Strains and their Effect on Quality of Young Wines

The yeast has important role in fermentation of wine grapes and wine quality. The fermentation of wine grapes affect by efficiency of particular yeast strain, sugar content, pH, available temperature, etc. To evaluate the efficiency of yeast strains (Premier Cuvee, RS-1, RS-2, RS-3 and natural), present study was conducted on two wine grape varieties viz.; Sauvignon Blanc (White) and Cabernet Sauvignon (Red). Efficiency of yeast strains was evaluated in terms of conversion rate of sugar into alcohol. As per recorded data, strain RS-3 (Pichia kudriavzevii) was found more efficient than other strains in fermentation of Cabernet Sauvignon with efficiency of 84.4 per cent but in case of Sauvignon Blanc, the commercial culture Premier Cuevee was found superior over RS-3. The quality parameters of young wines of both the varieties were also affected by the used strains. Considering the efficiency and impact on various parameters of wines, local strain, i.e., RS-3 was found at par with commercial culture (Premier Cuvee). The RS-3 strain has potential to produce quality wines. However, studies on effects of RS-3 strain on some specific quality parameters of wines like varietal aroma compounds, flavours etc. are needed.

Iron regulation in tuberculosis research: promise and challenges

Tuberculosis is a major global health challenge and is far from being controlled. Development of resistance to currently available drugs due to the successful adaptation of the pathogen has been a major contributing factor for its control failure. Presently, there is an immense interest in identification of pathways, unique to the intracellular environment that could be utilized for the development of new and better drugs. In this sequence, targeting essential functions of Mycobacterium tuberculosis has emerged as a reliable strategy for containing the spread of the disease by this organism. The fact that iron has been known to be the key player required for its survival and ability to spread infection, the organism must carefully balance iron acquisition with iron uptake for its infectivity. Conversely, this iron homeostatic process could be disrupted to interfere with the survival and replication of this bacterium in host. Urgency to develop such an approach has been further strengthened with the worldwide recrudescence of tuberculosis especially in the developing nations of the world. In the current review, we have focused on the recent developments in targeting the essential functions of mycobacterium especially interfering in its iron homeostatic process. The relevance of iron for mycobacterial virulence, the intracellular survival and the immense potential of targeting iron-sulfur (Fe-S) cluster containing proteins in tuberculosis drug discovery has been discussed.

Reversible neurological syndromes with atypical pneumonia

Simultaneous or sequential involvement of lungs is frequently encountered with neurological syndromes like meningoencephalitis, cerebellitis, aseptic meningitis, transverse myelitis, or multiple cranial nerve palsies. However, pulmonary involvement is frequently overlooked when all the attention of physician is diverted to neurological disorder. Prompt and early recognition of such potentially treatable association is required to improve diagnostic and therapeutic outcome. We report six patients presenting with various neurological manifestations like meningitis, meningoencephalitis, and myelits associated with atypical pneumonia. With proper clinical correlation and relevant investigations, all of them were diagnosed in time and had remarkable recovery with appropriate treatment.

Effect of formulated root endophytic fungus Piriformospora indica and plant growth promoting rhizobacteria fluorescent pseudomonads R62 and R81 on Vigna mungo

In the present investigation, the effect of three beneficial organisms (root endophytic fungus Piriformospora indica (Pi) and pseudomonads strains R62 and R81) and their four different consortia (Pi+R62, Pi+R81, R62+R81, Pi+R62+R81) was investigated on the plant Vigna mungo through their inorganic carrier-based (talcum powder and vermiculite) formulations. All the treatments resulted in significant increase in growth parameters under glasshouse as well as field conditions and showed a consistency in their performance on moving from glasshouse to field conditions. In glasshouse conditions, a maximum increase of 4.5-fold in dry root weight and 3.9-fold in dry shoot weight compared to control was obtained with vermiculite-based consortium formulation of Pi+R81. In field studies using vermiculite as carrier, a maximum enhancement of 3.2-fold in dry root weight, 3.0-fold in dry shoot weight, 8.4-fold in number of nodules and 4.0-fold in number of pods in comparison to control was obtained with the bio-inoculant formulation containing consortium of Pi+R81. The same treatment also caused the highest improvement of 1.9-fold in nitrogen content and 1.7-fold in phosphorus content, while the highest increase of 1.4-fold in potassium content was obtained with Pi alone.

The most effective and essential way of improving the oral health status education

BACKGROUND

Oral health is an essential component of health throughout life. Two major oral diseases, dental caries and periodontal diseases, are both ancient and widespread. The oral health situation analysis demands that the preventive program be implemented in both the developing and developed countries. Therefore, this study was conducted to evaluate the effectiveness of delivering the primary preventive strategies through non dental and dental personnel.

AIMS AND OBJECTIVES

To develops the preventive package for improving the oral health status of children utilizing the different communication approaches. To find out the most feasible and effective communication approach for delivering the preventive package. To evaluate the changes produced in terms of various soft and hard core parameters after 6 months of implementation of the oral-health preventive package in the school children of different study groups as compared to control.

MATERIALS AND METHODS

This study was conducted on total of 972 children in the age group of 5-16 years who were randomly selected from four schools of Chandigarh and Panchkula to evaluate and compare the prevalence of dental caries and knowledge, attitude, and practice about oral health.

RESULTS AND CONCLUSIONS

The results of various parameters indicate that direct communication through the dentist proved to be the most effective communication approach as compared to the other two indirect communication approaches.

Prevalence of stress among resident doctors working in Medical Colleges of Delhi

The present cross-sectional study was conducted from November 2007 to December 2008 in four medical colleges and associated hospitals of Delhi. Study subjects comprised 930 resident doctors. The overall prevalence of stress was found to be 32.8% in resident doctors from all colleges. Out of 930 resident doctors, 165 (17.7%) had mild stress, 113 (12.2%) had moderate stress, and 27 (2.9%) were severely stressed. Important reasons of stress as perceived by the study subjects included long duty hours, departmental academic activities, financial constraints, family and emotional problems in the decreasing order of preference. Important factors significantly associated with stress-included existence of children, year of residency, type of department, and presence or absence of job satisfaction, having close friends, spending time with family/friends, and place of graduation. In the multivariate model, year of residency, giving time to family and or friends, having close friends during residency, job satisfaction, and state of graduation came out as predictors of stress.

Application of inorganic carrier-based formulations of fluorescent pseudomonads and Piriformospora indica on tomato plants and evaluation of their efficacy

AIMS

Fluorescent pseudomonads are widely used as bioinoculants for improving plant growth and controlling phytopathogenic fungi. Piriformospora indica (Pi), a symbiotic root endophyte, also has beneficial effects on a number of plants. The present study focuses on the improvement of growth yields of tomato plants and control of Fusarium wilt using inorganic carrier-based formulations of two fluorescent pseudomonad strains (R62 and R81) and Pi.

METHODS AND RESULTS

The inorganic carrier-based formulations of pseudomonad strains and Pi were tested for plant growth promotion of tomato plants under glass house and field conditions. In controlled glass house experiments, 8·8-fold increase in dry root weight and 8·6-fold increase in dry shoot weight were observed with talcum powder-based consortium formulation of R81 and Pi. Field trial experiments ascertained the glfass house results with a considerable amount of increase in plant growth responses, and amongst all the treatments, R81 + Pi treatment performed consistently well in field conditions with an increase of 2·6-, 3·1- and 3·9-fold increase in dry root weight, shoot weight and fruit yield, respectively. The fluorescent pseudomonad R81 and Pi also acted as biocontrol agents, as their treatments could control the incidence of wilt disease caused by Fusarium oxysporum f.sp. lycopersici in tomato plants under glass house conditions.

CONCLUSIONS

The culture broths of pseudomonads R62, R81 and Pi were successfully used for development of talcum- and vermiculite-based bioinoculant formulations. In controlled glasshouse experiments, the talcum-based bioinoculant formulations performed significantly better over vermiculite-based formulations. In field experiments the talcum-based consortium formulation of pseudomonad R81 and Pi was most effective.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study suggests that the formulations of pseudomonad strains (R62 and R81) and Pi can be used as bioinoculants for improving the productivity of tomato plants. The application of such formulations is a step forward towards sustainable agriculture.

In situ chemichromic studies of interactions between a lutetium bis-octaalkyl-substituted phthalocyanine and selected biological cofactors

Spin-coated films, approximately 100 nm thick, of a newly synthesized bis[octakis(octyl)phthalocyaninato] lutetium(III) complex on ultrasonically cleaned glass substrates exhibit pronounced chemichromic behaviour with potential application in healthcare. In situ kinetic optical absorption spectroscopic measurements show that the phthalocyanine Q-band is red shifted by 60 nm upon oxidation arising from exposure to bromine vapour. Recovery to the original state is achieved by the treatment of the oxidized films with nicotinamide adenine dinucleotide and l-ascorbic acid (vitamin C) in an aqueous solution containing 1.5 M lithium perchlorate. The neutralization process is found to be governed by first-order kinetics. The linear increase of the reduction rate with increasing concentration of cofactors provides a basis for calibration of analyte concentrations ranging from 3.5 mM down to 0.03 mM.

Ocular morbidity in hearing impaired schoolchildren

AIMS

To determine the pattern and prevalence of ocular morbidity in hearing impaired schoolchildren.

METHODS

A cross-sectional descriptive study was conducted in the three different deaf schools of Kathmandu, Bhaktapur and Kavre districts. All children in the deaf school underwent complete ocular examination. Examination included visual acuity assessment, refraction, binocular vision assessment, and anterior and posterior segment evaluation.

RESULTS

Ocular examination was carried out in 279 children with age range within 5 to 20 years (mean age 14.1 ± 3.14 years). Ocular morbidity was detected in 78 (28%) children with 46 (16.48%) having refractive errors. Seventy eight percent children did not have corrective lenses despite having refractive errors. Two children were found to have pigmentary retinopathy where electro-retinogram findings suggested Usher's Syndrome in one child. Another child was found to have Waardenburg Syndrome.

CONCLUSIONS

Hearing impaired children are at an increased risk of having ocular morbidity. Hence, periodic eye examinations are important in deaf children.

Community transcriptomics reveals universal patterns of protein sequence conservation in natural microbial communities

Background

Combined metagenomic and metatranscriptomic datasets make it possible to study the molecular evolution of diverse microbial species recovered from their native habitats. The link between gene expression level and sequence conservation was examined using shotgun pyrosequencing of microbial community DNA and RNA from diverse marine environments, and from forest soil.

Results

Across all samples, expressed genes with transcripts in the RNA sample were significantly more conserved than non-expressed gene sets relative to best matches in reference databases. This discrepancy, observed for many diverse individual genomes and across entire communities, coincided with a shift in amino acid usage between these gene fractions. Expressed genes trended toward GC-enriched amino acids, consistent with a hypothesis of higher levels of functional constraint in this gene pool. Highly expressed genes were significantly more likely to fall within an orthologous gene set shared between closely related taxa (core genes). However, non-core genes, when expressed above the level of detection, were, on average, significantly more highly expressed than core genes based on transcript abundance normalized to gene abundance. Finally, expressed genes showed broad similarities in function across samples, being relatively enriched in genes of energy metabolism and underrepresented by genes of cell growth.

Conclusions

These patterns support the hypothesis, predicated on studies of model organisms, that gene expression level is a primary correlate of evolutionary rate across diverse microbial taxa from natural environments. Despite their complexity, meta-omic datasets can reveal broad evolutionary patterns across taxonomically, functionally, and environmentally diverse communities.

Lytic bacteriophages specific to Flavobacterium columnare rescue catfish, Clarias batrachus (Linn.) from columnaris disease

This investigation was aimed to find out appropriate strategy against antibiotic resistant bacterial fish pathogen, F. columnare. This pathogen was found persistently associated with fishes causing columnaris disease and ensuing mass mortality in hatchery and culture system of Sub - Himalayan region. Nine lytic F. columnare phages (FCP1 - FCP9) specific to its fifteen isolates were isolated from the water and bottom sediments of various geo-climatic regions of North India. The F. columnare phage FCP1 (made of hexagonal head and non contractile long tail belonging to family Podovariedae, a member of DNA virus) exhibited broader host range to lyse 9 out of 15 isolates of F. columnare. Therapeutic ability of FCP1 phage was assessed in C. batrachus inoculated intramuscularly (im) with virulent bacterial isolate FC8 and post inoculated (PI) with FCP1 phage (@ 10(8) : 10(6):: cfu : pfu) through intramuscular (im), immersion (bath) and oral (phage impregnated feed) treatment. Significant (p < 0.001) reduction (less than 10(-3) cfu ml(-1)) in host bacterium in the sera, gill, liver and kidney of challenged fishes was noted after 6 hr of phage treatment. Quantum of phage played a significant role in bringing down bacterial population as in the sera of dose 1 (@ 4.55 x 10(6) pfu ml(-1)) and dose 2 (@ 9.15 x 10(6) pfu ml(-1)) treated fishes mean log10 cfu value reduced by 3 logs (58.39%) and 5 logs (73.77%) at 96 hr, respectively. Phage treatment led to disappearance of gross symptoms, negative bacteriological test, detectable phage and 100% survival in experimentally infected C. batrachus. Result of this study provides evidence of profound lytic impact of FCP1 phage and represents its interesting therapeutic importance against antibiotic resistant F. columnare.