Antidepressant Drugs and Infectious Disease.

Antidepressant drugs and infectious disease.

J Psychosoc Nurs Ment Health Serv. 2013 Jul; 51(7): 11-4
Howland RH

Clostridium difficile (C.difficile) infection (CDI) is a common and clinically significant cause of diarrhea associated with the use of antibiotic drugs. Two observational studies have suggested that antidepressant drug use is associated with an increased risk of developing CDI. Because of the potential public health significance of this finding, this article critically evaluates the methodology of these studies and provides evidence to question the plausibility and validity of this finding. The safety of antidepressant and other psychotropic drugs should not be taken for granted, but studies that receive media attention may cause harm if their findings are not valid and they result in a reluctance to use these drugs for treating serious mental disorders. HubMed – drug

A Novel Approach for High Level Expression of Soluble Recombinant Human Parathyroid Hormone (rhPTH 1-34) in Escherichia coli.

Avicenna J Med Biotechnol. 2013 Jul; 5(3): 193-201
Hamedifar H, Salamat F, Saffarion M, Ghiasi M, Hosseini A, Lahiji H, Nouri Z, Arfae H, Mahboudi F

Parathyroid hormone (PTH) secreted by parathyroid glands regulates the metabolism of calcium and phosphorus in bone and kidney. Thereby, it can stimulate bone formation, and is a promising agent in the treatment of osteoporosis. Mature form of PTH consists of 84 amino acids; however, the first 34 residues of PTH cover the majority of hormonal action.In this study, the fusion form of highly soluble rhPTH was expressed at high level in Escherichia coli (E. coli). His6-thioredoxin as an extension for rhPTH improves the solubility of inclusion body. His6-thioredoxin-hPTH (1-34) was ligated into pET32a expression vector. The insertion of 5 amino acids (Asp-Asp-Asp-Asp-Lys) in the N-terminal of PTH made this protein to be digestable specifically by enterokinase enzyme. The fusion form of rhPTH was harvested and purified by immobilized affinity chromatography followed by digestion with enterokinase. Digested rhPTH was purified by applying on size exclusion and ion exchange chromatography to get the highest purity.The mass spectroscopy analysis shows rhPTH molecular weight was 4117.5 Da. The purity was measured by HPLC column which showed more than 97%. Bioassay analysis of rhPTH was performed on rat sarcoma cell UMR-106 in parallel with commercially available rhPTH, Forteo. The result was measured through immunofluorescence detection kit. The data showed that the potency of rhPTH was comparable with commercially available medicine.Thioredoxin was applied as a fusion partner for production of highly soluble rhPTH. This specific fusion partner increased protein solubility and decreased protease reactivity. Purification process was optimized for high recovery and for purity more than 99%. As its biological activity is comparable with marketed drug, this protein is qualified for biopharmaceutical usage. HubMed – drug

Predictions of Protein-Protein Interfaces within Membrane Protein Complexes.

Avicenna J Med Biotechnol. 2013 Jul; 5(3): 148-57
Asadabadi EB, Abdolmaleki P

Prediction of interaction sites within the membrane protein complexes using the sequence data is of a great importance, because it would find applications in modification of molecules transport through membrane, signaling pathways and drug targets of many diseases. Nevertheless, it has gained little attention from the protein structural bioinformatics community.In this study, a wide variety of prediction and classification tools were applied to distinguish the residues at the interfaces of membrane proteins from those not in the interfaces.The tuned SVM model achieved the high accuracy of 86.95% and the AUC of 0.812 which outperforms the results of the only previous similar study. Nevertheless, prediction performances obtained using most employed models cannot be used in applied fields and needs more effort to improve.Considering the variety of the applied tools in this study, the present investigation could be a good starting point to develop more efficient tools to predict the membrane protein interaction site residues. HubMed – drug

Human wound infections caused by Neisseria animaloris and Neisseria zoodegmatis, former CDC Group EF-4a and EF-4b.

Infect Ecol Epidemiol. 2013; 3:
Heydecke A, Andersson B, Holmdahl T, Melhus A

Neisseria animaloris and Neisseria zoodegmatis, former CDC Group EF-4a and -4b, are considered to be rare zoonotic pathogens, usually associated with dog or cat bites. The aim of the study was to phenotypicaly characterize 13 EF-4 isolates from wound infections, determine their antibiotic susceptibility and to follow the clinical outcome of the patients.13 of the EF-4 isolates were cultured on agar plates. Conventional biochemical tests and the Biolog system were used for phenotypical identification. An arbitrary primed polymerase chain reaction (AP-PCR) was carried out to determine the genetic profiles. Minimum inhibitory concentration (MIC) values were determined for different antibiotics were determined. According to this, clinical data for the patients were recorded.11 isolates were identified as N. animaloris and 2 as N. zoodegmatis due to the production of arginine dihydrolase. A majority of the patients had a history of dog bite. In 6 cases only grewth of N. animaloris or zoodegmatis was registered. When a patient received antibiotic treatment the most common drug of choice was penicillin V. Only 3 patients received treatment for which the isolated EF-4 bacterium was fully susceptible.Human infections involving N. animaloris and N. zoodegmatis usually present themselves as local wound infection, but severe complications can occur. Despite their pathogenic potentia, l N. animaloris and N. zoodegmatis are often misidentified, dismissed as skin contaminants or not recognized at all. Due to the fact that N. animaloris and N. zoodegmatis are significant pathogens in animal bites, physicians should keep these bacteria in mind when choosing antibiotic therapy. HubMed – drug