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1.
J Mycol Med ; 30(2): 100924, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32037102

ABSTRACT

Cryptococcus neoformans, an encapsulated fungal pathogen is evolving as a major threat to immune-compromised patients and rarely to healthy individuals also. The cell wall bound capsular polysaccharide, melanin pigment and biofilm formation are major virulence factors that are known to contribute to cryptococcal meningitis. In the present study, a furanone derivative, (E)-5-benzylidenedihydrofuran-2(3H)-one (compound-6) was evaluated against biofilm of seven different strains of C. neoformans in melanized and non-melanized condition. In addition, the efficacy of compound-6 in activation of TLR-2, opsonophagocytosis, and modulation of cytokine expression during phagocytosis were studied. During the biofilm study, we found that moderate capsule size favored biofilm formation. Interestingly, the minimum biofilm eradication concentration (MBEC0.5) of melanized biofilm was found to be achieved at 1- to 1.7-fold higher MBEC0.5 of non-melanized cells. The maximum eradication of 77% and 69% of non-melanized and melanized biofilm were observed. The capsule size was reduced to half of its size with marked changes in morphology. Furthermore, expression of TLR2, iNOS and pro-inflammatory cytokines such as TNF-α, IL-12, and IFN-γ were also facilitated by compound-6. The correlation analysis showed a positive correlation between phagocytosis and the expression of TLR-2, iNOS, IL-6, IL-12. Collectively, the significant effect of compound-6, anti-melanization activity, antibiofilmand effective immunomodulant could be an interesting dual strategy drug agonist against cryptococcal meningitis.


Subject(s)
Antifungal Agents/pharmacology , Biofilms/drug effects , Cryptococcus/drug effects , Opsonin Proteins/physiology , Phagocytosis/drug effects , Animals , Antifungal Agents/chemical synthesis , Antifungal Agents/chemistry , Bacterial Capsules/drug effects , Bacterial Capsules/physiology , Cells, Cultured , Cryptococcosis/immunology , Cryptococcosis/microbiology , Cryptococcus/physiology , Cryptococcus neoformans/drug effects , Cryptococcus neoformans/physiology , Furans/chemical synthesis , Furans/chemistry , Furans/pharmacology , Humans , Macrophages/drug effects , Macrophages/physiology , Melanins/metabolism , Meningitis, Cryptococcal/immunology , Meningitis, Cryptococcal/microbiology , Mice , Microbial Sensitivity Tests , Opsonin Proteins/metabolism
2.
J Appl Microbiol ; 124(2): 408-422, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29178633

ABSTRACT

AIMS: To enhance the antimicrobial and antibiofilm activity of norfloxacin against the planktonic and biofilm mode of growth in ESKAPE pathogens using chemically modified norfloxacin salts. METHODS AND RESULTS: Antimicrobial testing, synergy testing and time-kill curve analysis were performed to evaluate antibacterial effect of norfloxacin carboxylic acid salts against ESKAPE pathogens. In vivo efficacy to reduce bacterial bioburden was evaluated in zebrafish infection model. Crystal violet assay and live-dead staining were performed to discern antibiofilm effect. Membrane permeability, integrity and molecular docking studies were carried out to ascertain the mechanism of action. The carboxylic acid salts, relative to parent molecule norfloxacin, displayed two- to fourfold reduction in minimum inhibitory concentration against Staphylococcus aureus and Pseudomonas aeruginosa, in addition to displaying potent bacteriostatic effect against certain members of ESKAPE pathogens. In vivo treatments revealed that norfloxacin tartrate (SRIN2) reduced MRSA bioburden by greater than 1 log fold relative to parent molecule in the muscle tissue. In silico docking with gyrA of S. aureus showed increased affinity of SRIN2 towards DNA gyrase. The enhanced antibacterial effect of norfloxacin salts could be partially accounted by altered membrane permeability in S. aureus and perturbed membrane integrity in P. aeruginosa. Antibiofilm studies revealed that SRIN2 (norfloxacin tartrate) and SRIN3 (norfloxacin benzoate) exerted potent antibiofilm effect particularly against Gram-negative ESKAPE pathogens. The impaired colonization of both S. aureus and P. aeruginosa due to improved norfloxacin salts was further supported by live-dead imaging. CONCLUSION: Norfloxacin carboxylic acid salts can act as potential alternatives in terms of drug resensitization and reuse. SIGNIFICANCE AND IMPACT OF THE STUDY: Our study shows that carboxylic acid salts of norfloxacin could be effectively employed to treat both planktonic- and biofilm-based infections caused by select members of ESKAPE pathogens.


Subject(s)
Anti-Bacterial Agents/pharmacology , Biofilms/drug effects , Gram-Negative Aerobic Bacteria/drug effects , Gram-Negative Bacterial Infections/microbiology , Norfloxacin/pharmacology , Staphylococcus aureus/drug effects , Acinetobacter baumannii/drug effects , Acinetobacter baumannii/growth & development , Acinetobacter baumannii/physiology , Animals , Anti-Bacterial Agents/chemistry , Carboxylic Acids/chemistry , Carboxylic Acids/pharmacology , Enterobacter/drug effects , Enterobacter/growth & development , Enterobacter/physiology , Enterococcus faecium/drug effects , Enterococcus faecium/growth & development , Enterococcus faecium/physiology , Escherichia coli/drug effects , Escherichia coli/growth & development , Escherichia coli/physiology , Gram-Negative Aerobic Bacteria/growth & development , Gram-Negative Aerobic Bacteria/physiology , Klebsiella pneumoniae/drug effects , Klebsiella pneumoniae/growth & development , Klebsiella pneumoniae/physiology , Microbial Sensitivity Tests , Norfloxacin/chemistry , Pseudomonas aeruginosa/drug effects , Pseudomonas aeruginosa/growth & development , Pseudomonas aeruginosa/physiology , Staphylococcal Infections/microbiology , Staphylococcus aureus/growth & development , Staphylococcus aureus/physiology
3.
Asian Pac J Cancer Prev ; 12(6): 1533-5, 2011.
Article in English | MEDLINE | ID: mdl-22126494

ABSTRACT

While there has been much research in identifying risk factors and prognostic factor for breast cancer for breast cancer survival, the research specific to South Indian population is limited: Most of the association studies between breast cancer and risk factor have been widely studied in developed countries. This study attempts to explore the survival experience of breast cancer patients treated under adjuvant and neo-adjuvant therapy. The data were obtained from a Government Cancer Hospital, Tamil Nadu, South India and included 522 women diagnosed and treated with adjuvant and neo-adjuvant therapy between January 2000 to December 2008 and follow up to May 2010. The survival experiences under two treatments are presented using Kaplan-Meier survival curves. The important prognostic variables for response to treatment survival were identified using Cox regression with and without time-dependent covariates. Of the 522 cases, 248(47.5%) were of stage 2 (A and B), 249 (47.7%) were of stage 3 (A and B). About 90% received neo-adjuvant therapy. About 94% of the patients had response to treatment. The Cox model showed that apart from the chemotherapy, number of children, child birth status and stage 3B and 4 turn out to be significant predictors for response to treatment survival. This is the first study to evaluate adjuvant therapy effects under hospital setup in South India. The results show that response to treatment survival is related poor in advanced stage patients under treatment.


Subject(s)
Breast Neoplasms/drug therapy , Breast Neoplasms/mortality , Chemotherapy, Adjuvant , Disease-Free Survival , Female , Humans , India , Kaplan-Meier Estimate , Neoplasm Staging , Proportional Hazards Models , Survival Analysis , Treatment Outcome
4.
Med J Armed Forces India ; 66(2): 188-9, 2010 Apr.
Article in English | MEDLINE | ID: mdl-27375335
5.
BMC Genomics ; 8: 435, 2007 Nov 27.
Article in English | MEDLINE | ID: mdl-18042279

ABSTRACT

BACKGROUND: Superoxide dismutases (SOD) are ubiquitous metalloenzymes that catalyze the disproportion of superoxide to peroxide and molecular oxygen through alternate oxidation and reduction of their metal ions. In general, SODs are classified into four forms by their catalytic metals namely; FeSOD, MnSOD, Cu/ZnSOD and NiSOD. In addition, a cambialistic form that uses Fe/Mn in its active site also exists. Cyanobacteria, the oxygen evolving photosynthetic prokaryotes, produce reactive oxygen species that can damage cellular components leading to cell death. Thus, the co-evolution of an antioxidant system was necessary for the survival of photosynthetic organisms with SOD as the initial enzyme evolved to alleviate the toxic effect. Cyanobacteria represent the first oxygenic photoautotrophs and their SOD sequences available in the databases lack clear annotation. Hence, the present study focuses on structure and sequence pattern of subsets of cyanobacterial superoxide dismutases. RESULT: The sequence conservation and structural analysis of Fe (Thermosynechococcus elongatus BP1) and MnSOD (Anabaena sp. PCC7120) reveal the sharing of N and C terminal domains. At the C terminal domain, the metal binding motif in cyanoprokaryotes is DVWEHAYY while it is D-X-[WF]-E-H-[STA]-[FY]-[FY] in other pro- and eukaryotes. The cyanobacterial FeSOD differs from MnSOD at least in three ways viz. (i) FeSOD has a metal specific signature F184X3A188Q189.......T280......F/Y303 while, in Mn it is R184X3G188G189......G280......W303, (ii) aspartate ligand forms a hydrogen bond from the active site with the outer sphere residue of W243 in Fe where as it is Q262 in MnSOD; and (iii) two unique lysine residues at positions 201 and 255 with a photosynthetic role, found only in FeSOD. Further, most of the cyanobacterial Mn metalloforms have a specific transmembrane hydrophobic pocket that distinguishes FeSOD from Mn isoform. Cyanobacterial Cu/ZnSOD has a copper domain and two different signatures G-F-H-[ILV]-H-x-[NGT]-[GPDA]-[SQK]-C and G-[GA]-G-G-[AEG]-R-[FIL]-[AG]-C-G, while Ni isoform has an nickel containing SOD domain containing a Ni-hook HCDGPCVYDPA. CONCLUSION: The present analysis unravels the ambiguity among cyanobacterial SOD isoforms. NiSOD is the only SOD found in lower forms; whereas, Fe and Mn occupy the higher orders of cyanobacteria. In conclusion, cyanobacteria harbor either Ni alone or a combination of Fe and Ni or Fe and Mn as their catalytic active metal while Cu/Zn is rare.


Subject(s)
Cyanobacteria/enzymology , Superoxide Dismutase/chemistry , Superoxide Dismutase/classification , Amino Acid Sequence , Anabaena/enzymology , Binding Sites , Conserved Sequence , Hydrogen Bonding , Iron/chemistry , Iron/metabolism , Manganese/chemistry , Manganese/metabolism , Models, Molecular , Nickel/chemistry , Nickel/metabolism , Sequence Alignment , Structural Homology, Protein , Superoxide Dismutase/genetics , Superoxide Dismutase/metabolism
7.
Med J Armed Forces India ; 60(2): 211-2, 2004 Apr.
Article in English | MEDLINE | ID: mdl-27407630
8.
Indian J Gastroenterol ; 22(3): 82-4, 2003.
Article in English | MEDLINE | ID: mdl-12839377

ABSTRACT

BACKGROUND: Intussusception is the most common cause of intestinal obstruction in young children and has been reported as a complication of a recently withdrawn tetravalent reassortant rotavirus vaccine. METHODS: We studied the history, clinical presentation, management and outcome of intussusception presenting to a tertiary care hospital in southern India over a 10-year period, in order to assess potential association with diarrheal disease and immunization. RESULTS: Data from 137 index cases and 280 control subjects indicated that the risk of diarrheal disease or oral polio vaccine administration in the month prior to presentation was similar in the index cases and controls. Mean time to presentation to hospital after developing symptoms was 1.8 days, and 77.3% of patients required surgery, with 47.4% undergoing intestinal resection. Mortality was 0.006%. CONCLUSIONS: No association could be demonstrated between gastroenteritis or oral poliovirus vaccine immunization and intussusception in southern Indian children. These children presented later and required operative intervention more frequently than has been reported in other studies, but had a good outcome with low mortality.


Subject(s)
Ileocecal Valve , Intussusception/therapy , Case-Control Studies , Child Welfare , Child, Preschool , Diarrhea/epidemiology , Diarrhea/therapy , Female , Humans , Ileal Diseases/epidemiology , Ileal Diseases/therapy , Immunization , India/epidemiology , Infant , Infant Welfare , Intussusception/epidemiology , Male , Poliomyelitis/epidemiology , Poliomyelitis/therapy , Poliovirus Vaccine, Oral/administration & dosage , Retrospective Studies , Treatment Outcome
9.
Trans R Soc Trop Med Hyg ; 95(5): 491-2, 2001.
Article in English | MEDLINE | ID: mdl-11706656

ABSTRACT

VP7 and VP4 genotypes of 82 rotavirus strains from children with acute diarrhoea during November 1998-January 1999, in 4 Indian towns, were determined by reverse-transcription PCR. Overall, 68/82 (83%) could be VP7- and 52/82 (63%) VP4-typed. Geographical differences in rotavirus circulation have implications for future vaccination strategies.


Subject(s)
Rotavirus Infections/epidemiology , Rotavirus/classification , Child, Preschool , Diarrhea/epidemiology , Diarrhea/virology , Enzyme-Linked Immunosorbent Assay , Genotype , Humans , India/epidemiology , Infant , Polymerase Chain Reaction/methods , Rotavirus/genetics
10.
Med J Armed Forces India ; 57(1): 22-5, 2001 Jan.
Article in English | MEDLINE | ID: mdl-27365572

ABSTRACT

All pregnant mothers attending antenatal clinic, mothers delivering at Command Hospital (Air Force) and parents of infants attending immunization clinic at Command Hospital (Air Force) from the period June 1998 to July 1999 are included in this retrospective and prospective cross sectional study. A preformatted questionnaire was designed to assess the practices related to breast feeding during antenatal, in labour room and postnatal ward both for the period pre BFHIand post BFH1 Programme initiated at Command Hospital (Air Force). 225 mothers were included in the study with 90 belonging to pre BFHI group (A) and 135 to post BFHI group (B). Significant changes in the breast feeding practices including antenatal advice on breast feeding and breast examination in group A & B were observed (22.3% vs 82.9% and 13.3% vs 74.8%), rooming in with mother and first feed within 1/2 hr (64.4% vs 92.5% and 35.5% vs 96.5%), teaching skill of breast feeding and manual expression (55.5% vs 91.8% vs 24.4% vs 74.0%). Other important changes included total discontinuation of formula feeds, exclusive breast milk in all preterm infants and avoiding all forms of prelacteal feeds. This study strengthens the fact that appropriate education and training of health care givers can result in reversing practices which are 'inappropriately baby friendly' to become 'appropriately baby and mother friendly'. Command Hospital (Air Force) happens to be first service hospital to be recognized as baby friendly. The experience could be applied to achieve the target of all service hospitals becoming baby friendly.

11.
Med J Armed Forces India ; 57(2): 110-3, 2001 Apr.
Article in English | MEDLINE | ID: mdl-27407310

ABSTRACT

This prospective, cross sectional population study was carried out to determine the relationship between maternal haemoglobin concentration and birth weight in different socioeconomic groups in a tertiary care teaching hospital. 500 cases each from two teaching hospitals about whom information on socioeconomic status, haemoglobin concentration and birth weight was known were included in the study. This was a stratified random study based on the preselected inclusion and exclusion criteria. 149 (14.9%) women belonged to upper socioeconomic group, 119 (11.9%) to upper middle, 125 (12.5%) to lower middle, 90 (9.0%) to upper lower and 517 (51.7%) to lower group. Mean haemoglobin level was found to be lower in low socioeconomic group as compared to high socioeconomic group and was statistically significant (F value of 18.2521 & p 0.000). The lowest Hb level was 4.0g/dl and highest was 15.0g/dL Majority of pregnant women (89.3%) had their lowest haemoglobin level during the second trimester as compared to first trimester (0.8%) and third trimester (9.9%). The mean birth weight in upper socioeconomic group was 2.7508 kg, 2.7556 kg in upper middle group, 2.8802 kg in lower middle group, 2.7876 kg in upper lower group and 2.7515 in lower socioeconomic group. By analysis of variance test it was found that the mean birth weight did not vary significantly between different socioeconomic groups with an F value of 1.3398 and p value of 0.2450. The correlation analysis of haemoglobin concentration with birth weight suggested that for every rise of haemoglobin concentration by 1.0g/dl the birth weight reduced by 03839 kg (highly significant p < 0.001). In the present study there was significant inverse relationship of maternal haemoglobin concentration to birth weight Results are in agreement with the hypothesis that a higher blood viscosity is a risk factor for sub optimal placenta-perfusion.

12.
Med J Armed Forces India ; 56(3): 219-224, 2000 Jul.
Article in English | MEDLINE | ID: mdl-28790712

ABSTRACT

Failure to thrive is a commonly encountered problem in Paediatric practice. This essentially generic term refers to children whose attained weight or rate of weight gain is significantly below that of other children of similar age and same sex. Several defining criteria have been proposed and help to differentiate true failure to thrive from other conditions causing apparent growth failure. There are numerous organic causes of failure to thrive, but non-organic failure to thrive is also an important entity and is caused by social, psychological and environmental factors. The clinical features are those of malnutrition, signs of underlying organic cause and specific manifestations of environmental/psychosocial deprivation. Indiscriminate laboratory investigations are usually non-contributory and have no role in evaluation. Management requires a multidisciplinary approach and hospitalization has a specific role. Although nutritional rehabilitation is the cornerstone of therapy, treatment of underlying factors-medical, psychological, social and environmental-should receive equally important attention. Long term physical, developmental and behavioural sequelae are known to occur in children with failure to thrive.

14.
Indian Pediatr ; 35(2): 139-45, 1998 Feb.
Article in English | MEDLINE | ID: mdl-9707856
15.
Indian Pediatr ; 35(5): 429-35, 1998 May.
Article in English | MEDLINE | ID: mdl-10216624

ABSTRACT

BACKGROUND: In children with lower respiratory tract symptoms, the elicited signs are not enough to distinguish common diagnosis like pneumonic consolidation, foreign body aspiration and atelectasis. Radiology and bronchoscopy would identify the true nature of the etiology. DESIGN: Prospective study. SUBJECTS: Thirty five children with both acute and chronic lower respiratory tract symptomatology, were analyzed for clinical and radiological signs of atelectasis. RESULTS: There were 23 cases in the acute group and 12 in chronic group. Acute group included cases of pneumonia, foreign body aspiration and mucus plug syndrome. Chronic group included cases of congenital heart disease, endobronchial tuberculosis and bronchial stenosis. Clinical recognition of atelectasis on the basis of localized loss of breath sounds and mediastinal shift was seen only in a minority of cases (8/35). The presence of atelectasis in children with pneumonia, missed clinically were diagnosed by the presence of tracheal shift, elevated hemidiaphragm and silhouette sign. In 21 cases, silhouette sign was positive making it an important radiological sign. Twenty one children underwent either diagnostic or/and therapeutic bronchoscopy. Findings included foreign bodies (n = 5), mucus plugs (n = 4), narrowing of main bronchus (n = 4) and inflammatory mucoid secretions and narrowing of lumen (n = 8). There were no major complications. CONCLUSION: The diagnosis of atelectasis in children may pose difficulties and there is a need to have a high index of suspicion to exclude atelectasis in children with either acute or chronic respiratory tract symptomatology.


Subject(s)
Pulmonary Atelectasis/diagnostic imaging , Pulmonary Atelectasis/etiology , Acute Disease , Bronchial Diseases/complications , Bronchoscopy , Child , Child, Preschool , Chronic Disease , Constriction, Pathologic/complications , Diagnosis, Differential , Foreign Bodies/complications , Heart Defects, Congenital/complications , Humans , Infant , Lung , Pneumonia/complications , Prospective Studies , Radiography , Tuberculosis, Pulmonary/complications
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