Association of microneme antigens of Plasmodium brasilianum merozoites with knobs and other parasite-induced structures in host erythrocytes.

The localization of Plasmodium brasilianum antigens, common to merozoite micronemes and parasite-induced structures in the host erythrocyte, was determined by means of immunogold electron microscopy and monoclonal antibodies directed against blood stages of this parasite. All monoclonal antibodies reacted with micronemes. In addition, some reacted with either knob protrusions or caveolae of the host erythrocyte membrane; one reacted with a parasite-derived antigen present in the erythrocyte cytoplasm. Gold particles appeared over the membranes of ring-infected cells before the appearance of knobs and caveolae. We hypothesize that at least some knob- and caveolae-associated antigens of P. brasilianum are inserted into the erythrocyte membrane at the time of merozoite invasion.     

Overview for various aspects of the health benefits of Piper longum linn. fruit

Herbal remedies have become popular, due in part to the lower risk of adverse reactions. Thousands of plants have been used traditionally to treat various diseases. Among them, species of the genus Piper are important medicinal plants used in various systems of medicine. The Piper longum fruit has been used in traditional medicine, including the Ayurvedic system of medicine. Although there are numerous indications for its use, controlled trials are needed to determine its efficacy. The primary constituents isolated from various parts of P. longum are piperine, piperlongumine, sylvatin, sesamin, diaeudesmin piperlonguminine, pipermonaline, and piperundecalidine. It is most commonly used to treat chronic bronchitis, asthma, constipation, gonorrhea, paralysis of the tongue, diarrhea, cholera, chronic malaria, viral hepatitis, respiratory infections, stomachache, bronchitis, diseases of the spleen, cough, and tumors. This study provides detailed information about the P. longum fruit, including phytochemistry, pharmacological profile and safety profile. In view of the commercial, economic, and medicinal importance of the P. longum plant, it is useful for researchers to study the plant in detail.     

Multicenter Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry Study for Identification of Clinically Relevant Nocardia spp.

This multicenter study analyzed Nocardia spp., including extraction, spectral acquisition, Bruker matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) identification, and score interpretation, using three Nocardia libraries, the Bruker, National Institutes of Health (NIH), and The Ohio State University (OSU) libraries, and compared the results obtained by each center. A standardized study protocol, 150 Nocardia isolates, and NIH and OSU Nocardia MALDI-TOF MS libraries were distributed to three centers. Following standardized culture, extraction, and MALDI-TOF MS analysis, isolates were identified using score cutoffs of ≥2.0 for species/species complex-level identification and ≥1.8 for genus-level identification. Isolates yielding a score of <2.0 underwent a single repeat extraction and analysis. The overall score range for all centers was 1.3 to 2.7 (average, 2.2 ± 0.3), with common species generally producing higher average scores than less common ones. Score categorization and isolate identification demonstrated 86% agreement between centers; 118 of 150 isolates were correctly identified to the species/species complex level by all centers. Nine strains (6.0%) were not identified by any center, and six (4.0%) of these were uncommon species with limited library representation. A categorical score discrepancy among centers occurred for 21 isolates (14.0%). There was an overall benefit of 21.2% from repeat extraction of low-scoring isolates and a center-dependent benefit for duplicate spotting (range, 2 to 8.7%). Finally, supplementation of the Bruker Nocardia MALDI-TOF MS library with both the OSU and NIH libraries increased the genus-level and species-level identification by 18.2% and 36.9%, respectively. Overall, this study demonstrates the ability of diverse clinical microbiology laboratories to utilize MALDI-TOF MS for the rapid identification of clinically relevant Nocardia spp. and to implement MALDI-TOF MS libraries developed by single laboratories across institutions.     

Identification of Mycobacteria from Solid and Liquid Media by Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry in the Clinical Laboratory

Mycobacteria cause significant morbidity in humans. Rapid and accurate mycobacterial identification is important for improvement of patient outcomes. However, identification may be challenging due to the slow and fastidious growth of mycobacteria. Several diagnostic methods, such as biochemical, sequencing, and probe methods, are used for mycobacterial identification. We compared the matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) Biotyper system (Bruker Daltonics) to 16S rRNA/hsp65 sequencing and/or DNA probes (Gen-Probe) for mycobacterial identification. One hundred seventy-eight mycobacterial isolates grown on solid and/or broth medium were included in the study. MALDI-TOF MS identified 93.8% of the mycobacteria isolates accurately to the species level and 98.3% to the genus level, independent of the type of medium used for isolation. The identification of mycobacteria directly from cultures using MALDI-TOF MS allows for precise identification in an hour compared to traditional biochemical and phenotypic methods that can take weeks or probes and sequencing that may take a few hours. Identification by MALDI-TOF MS potentially reduces the turnaround time and cost, thereby saving resources within the health care system.     

Proximal humeral reconstruction using nail cement spacer in primary and metastatic tumours of proximal humerus

Limb salvage surgery for malignant tumours of proximal humerus is an operative challenge, where the surgeon has to preserve elbow and hand functions and retain shoulder stability with as much function as possible. We treated 14 consecutive patients with primary malignant or isolated metastasis of proximal humerus with surgical resection and reconstruction by nail cement spacer. There were 8 females and 6 males, with a mean age of 28.92 years (range 16–51 years) and a mean follow-up of 30.14 months (range 12–52 months). The diagnosis was osteosarcoma in 8 patients, chondrosarcoma in 4 patients and metastasis from thyroid and breast carcinoma in 1 patient each. One of our patients had radial nerve neuropraxia, 1 developed inferior subluxation and 3 developed distant metastasis. Two patients died of disease and one developed local recurrence leading to forequarter amputation, leaving a total of 11 patients with functional extremities for assessment at the time of final follow-up which was done using the Musculoskeletal Tumour Society (MSTS) score. Though we were able to preserve the elbow, wrist and hand functions in all patients, the abductor mechanism, deltoid muscle and axillary nerve were not salvageable in any of cases. The mean MSTS score at the time of final follow-up was 19.09. Thus, proximal humeral reconstruction using nail cement spacer is a technical simple, cost-effective and reproducible procedure which makes it a reliable option in subset of patients where the functions around the shoulder cannot be preserved despite costlier prosthesis.     

Syntheses and bioevaluation of substituted dihydropyridines for pregnancy-interceptive activity in hamsters

A number of 2,6-dimethyl-3,5-bis(methoxycarbonyl)-4-substituted-1,4- dihydropyridines were synthesized and evaluated for pregnancy-interceptive activity in mated hamsters. Out of 24 compounds, 12, 15, 21, 22, 28, and 34 caused a marked reduction in the number of implantations when administered on days 3-8 postcoitum. In an in vitro competition assay, none of the compounds exhibited noticeable binding affinity for uterine progesterone receptors. The results reported here have helped to identify new leads for developing pregnancy-interceptive agents and the active compounds do not seem to elicit their interceptive effect through receptor-mediated inhibition of progesterone action in hamster uterus.     

Functional and immunocytochemical characterization of D‐serine transporters in cortical neuron and astrocyte cultures

D‐serine is an endogenous coagonist of N‐methyl‐D‐aspartate (NMDA) receptors that plays an important role in synaptic function, neuronal development, and excitotoxicity. Mechanisms of D‐serine transport are important in regulation of extracellular D‐serine concentration and therefore of these critical processes. D‐serine can be transported with low affinity through the Na⁺‐dependent amino acid transporter termed ASCT2, whereas high‐affinity D‐serine uptake has been reported through the Na⁺‐independent transporter termed asc‐1. We investigated immunoreactivity for ASCT2 and asc‐1 and D‐serine transport kinetics in cultured cortical neurons and astrocytes to gain insight into how D‐serine transporters regulate CNS D‐serine levels. Both neurons and astrocytes exhibited low‐affinity Na⁺‐dependent D‐serine uptake (K_T > 1 mM) with broad substrate selectivity that was consistent with uptake through ASCT2. Both neurons and astrocytes also stained positively for ASCT2 in immunocytochemistry studies. Neurons but not astrocytes stained positively for the high‐affinity D‐serine transporter asc‐1, but no evidence of functional asc‐1 could be detected in neurons with conditions that produced such activity in cortical synaptosomes. These data support ASCT2 function in both neuron and astrocyte cultures and identify a discrepancy between observed asc‐1 immunoreactivity and lack of functional asc‐1 activity in neuron cultures. Together these findings further our knowledge of the processes that govern D‐serine regulation. © 2009 Wiley‐Liss, Inc.