Phytochemical Repurposing of Natural Molecule: Sabinene for Identification of Novel Therapeutic Benefits Using In Silico and In Vitro Approaches.

Repurposing of drugs/natural or synthetic chemicals is a promising approach to identify the new therapeutic indication/use and mode of action. In pharmaceuticals, this process is used to save the time and cost for the drug discovery process with reduced risk of failure. In the present studies, repurposing of a natural molecule: sabinene (major phytochemical in cardamom) was used to characterize the new biological activities using in silico as well as in vitro approaches. In silico similarity searching demonstrated that (+)-3-carene possessed the maximum structural similarity with sabinene. In vitro activities of (+)-3-carene were repurposed for sabinene based on similarity hypothesis (similar structures may have similar biological activities). In vitro studies demonstrated that sabinene is having antimicrobial activity and also showed concentration-dependent antioxidant activity by 2,2-diphenyl-1-picrylhydrazyl scavenging assay. Sabinene treatment protected the yeast cells from hydrogen peroxide-induced cytotoxicity in 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide assay. Moreover, it was found that sabinene treatment decreased the generation of oxidative stress and also decreased the activities of antioxidant enzymes; glutathione S-transferase, catalase, and lipid peroxidase as compared with untreated yeast cells. Sabinene was also found to have angiostatic and antiangiogenic effects. These results were supported by molecular docking studies against antiangiogenic targets. Therefore, the results of these studies suggested that structurally similar molecules are having the same activity. The phytochemical repurposing using in silico similarity searching as well as in vitro approaches can also be applied for other phytochemicals whose activities are not/less known. Furthermore, this could also be useful in the novel lead/scaffold discovery and target fishing.

Phenotypic and genotypic methods for the detection of methicillin resistant coagulase negative staphylococci: a comparative study.

CONS are the major cause of nosocomial infection in last decade and methicillin resistant CoNS has emerged as a major clinical problem. The present study was to compare different phenotypic methods with genotypic method PCR, for the detection of methicillin resistance in CoNS. 100 CoNS isolates from different samples were studied for the detection of mecA gene. PCR was considered as "gold standard". Oxacillin and cefoxitin antibiotics were used for different phenotypic tests (DD, Agar dilution and MHOX). The sensitivities of oxacillin and cefoxitin disks for all CONS were found to be 92.30% and 88.46% respectively and the specificities were 87.5% and 100% respectively. The sensitivities of the agar dilution test for oxacillin and cefoxitin were 86.53% and 80.76%, respectively, where as the specificities were 79.16% and 85.41%, respectively. The sensitivity of MHOX was observed to be 96.16% and specificity 72.91%. Cefoxitin D.D and oxacillin AD methods could be used as initial test for the determination of methicillin resistance in CoNS isolates. The result of MHOX shows that it could be the best single method for the evaluation of oxacillin resistance mediated by the mecA gene for all CoNS species.

Prevalence and antibiotic resistance pattern of metallo-beta-lactamase-producing Pseudomonas aeruginosa from burn patients--experience of an Indian tertiary care hospital.

The objective of the study is to determine the prevalence of Pseudomonas aeruginosa from burn patients, antibiotic resistance pattern and occurrence of acquired MBL-producing P. aeruginosa among isolates collected from burn patients. In this study, two phenotypic methods were used for the detection of MBL-producing P. aeruginosa: zone enhancement with EDTA-impregnated imipenem and ceftazidime discs, and modified Hodge test. One hundred fifty-four isolates of P. aeruginosa were obtained from July 2007 to July 2008. Infection was increased up to 95% in hospitalized patients for >50 days. Highest infection of 39% was found in patients, who had 41 to 50% of burn area followed by 19% in patients with 31 to 40% of burn area. The most common bacteria isolated were P. aeruginosa (55.0%), followed by Staphylococcus aureus (19.29%) and Klebsiella spp. (11.43%). Sixteen percent isolates of P. aeruginosa were positive for metallo-beta-lactamase production by both methods. Antibiotic resistance pattern of MBL-positive strains showed the highest resistance to ceftazidime (70%) followed by chloramphenicol (68%) and gentamicin (62.5%). Routine detection of MBLs ensuring optimal patient care and careful in vitro testing before antibiotic use may help in the prevention and treatment of burn patients infected with metallo-beta- lactamase-producing P. aeruginosa.

Atypical bacterial pathogens in community-acquired pneumonia in children: a hospital-based study.

A total of 243 children aged one month to five years with World Health Organization defined severe community acquired pneumonia were studied for the presence of atypical bacterial pathogens: 24 were found positive for mycoplasma infection. There was no significant association with any of the clinical, laboratory and radiological variables in children with pneumonia by the atypical pathogen.

Phenotypic and genotypic methods for the detection of methicillin resistant coagulase negative staphylococci: a comparative study.

CoNS are the major cause of nosocomial infection in last decade and methicillin resistant CoNS has emerged as a major clinical problem. The present study was to compare different phenotypic methods with genotypic method PCR, for the detection of methicillin resistance in CoNS. 100 CoNS isolates from different samples were studied for the detection of mecA gene. PCR was considered as "gold standard". Oxacillin and cefoxitin antibiotics were used for different phenotypic tests (DD, Agar dilution and MHOX). The sensitivities of oxacillin and cefoxitin disks for all CoNS were found to be 92.30% and 88.46% respectively and the specificities were 87.5% and 100% respectively. The sensitivities of the agar dilution test for oxacillin and cefoxitin were 86.53% and 80.76%, respectively, where as the specificities were 79.16% and 85.41%, respectively. The sensitivity of MHOX was observed to be 96.16% and specificity 72.91%. Cefoxitin D.D and oxacillin AD methods could be used as initial test for the determination of methicillin resistance in CoNS isolates. The result of MHOX shows that it could be the best single method for the evaluation of oxacillin resistance mediated by the mecA gene for all CoNS species.

Proteomic analysis of urinary protein markers for accurate prediction of diabetic kidney disorder.

AIM OF THE STUDY: Microalbuminuria is currently the only diagnostic tool available for early diagnosis of diabetic nephropathy. The test is based on immunological detection of small quantities of albumin in the urinary samples of diabetes patients. There are several limitations of the use of microalbuminuria as an index of renal function. It is therefore desirable to identify additional protein markers that would augment prediction of diabetic nephropathy. The aim of this study is to identify urinary protein markers for specific and more accurate prediction of nephropathy in diabetes patients. DESIGN: 100 registered Type II diabetic patients were studied. Abundant proteins of microalbuminuria positive urinary samples of these patients were analyzed by proteomics approaches of 2-Dimentional Gel Electrophoresis (2DGE) and mass spectrometry. RESULTS: 2-DGE analysis of the urine sample revealed four main proteins along with albumin in these samples. These were zinc alpha-2 glycoprotein, alpha-1 acid glycoprotein, alpha-1 microglobulin and IgG as identified by Matrix Assisted Laser Desorption Ionization-Tune of Flight (MALDI-ToF) and by western blot. Twenty control samples and three cases with microalbuminuria negative to positive transition does suggest the early and co-appearance of the markers with albumin. We have also analyzed full length spectrum of these samples by MALDI-ToF. CONCLUSION: Our study shows the presence of additional proteins in urine samples of microalbuminuria positive diabetes patients. These proteins can be used as markers for specific and accurate clinical analysis of Diabetic nephropathy. We propose a mass spectrometry based high throughput diagnostic approach to detect these markers in the urine sample.