Comparison of isoelectric focusing and polymerase chain reaction for the detection of β-lactamases

Extended spectrum β-lactamases (ESBLs) have been observed in virtually all the species of family Enterobacteriaceae. Threat posed by antibiotic resistance because of ESBLs is more serious as a number of technical problems are associated with the detection of these enzymes. Although a number of detection methods have been designed for ESBLs, every method has its own benefits and shortcomings as well. In earlier days, isoelectric focusing (IEF) was used as the gold standard for ESBL detection. This study was undertaken to compare IEF with polymerase chain reaction, a method which has been extensively used for ESBL detection these days.

Comparative genomic analysis of simple sequence repeats in three Plasmodium species

Simple sequence repeats (SSRs) are known to be responsible for genetic complexities and play major roles in gene and genome evolution. To this respect, malaria parasites are known to have rapidly evolving and complex genomes with complicated and differential pathogenic behaviors. Hence, by studying the whole genome comparative SSRs patterns, one can understand genomic complexities and differential evolutionary patterns of these species. We herein utilized the whole genome sequence information of three Plasmodium species, Plasmodium falciparum, Plasmodium vivax, and Plasmodium knowlesi, to comparatively analyze genome-wide distribution of SSRs. The study revealed that despite having the smallest genome size, P. falciparum bears the highest SSR content among the three Plasmodium species. Furthermore, distribution patterns of different SSRs types (e.g., mono, di, tri, tetra, penta, and hexa) in term of relative abundance and relative density provide evidences for greater accumulation of di-repeats and marked decrease of mono-repeats in P. falciparum in comparison to other two species. Overall, the types and distribution of SSRs in P. falciparum genome was found to be different than that of P. vivax and P. knowlesi. The latter two species have quite similar SSR organizations in many aspects of the data. The results were discussed in terms of comparative SSR patterns among the three Plasmodium species, uniqueness of P. falciparum in SSR organization and general pattern of evolution of SSRs in Plasmodium.

The potential use of Echinacea in acne: control of Propionibacterium acnes growth and inflammation

Acne is a chronic inflammatory disorder of skin follicles caused by the gram-positive bacterium Propionibacterium acnes. The possibility was investigated that a standardized preparation of Echinacea purpurea (Echinaforce®), with known antiviral, antiinflammatory and antibacterial properties, might provide a useful alternative treatment in the control of the disease. The herbal extract readily killed a standard laboratory strain of the bacterium and several clinical isolates. In cell culture models of human bronchial epithelial cells and skin fibroblasts, P. acne induced the secretion of substantial amounts of several pro-inflammatory cytokines, including IL-6 and IL-8 (CXCL8), as determined by means of cytokine-antibody arrays. However, the E. purpurea completely reversed this effect and brought the cytokine levels back to normal. Thus Echinaforce® could provide a safe two-fold benefit to acne individuals by inhibiting proliferation of the organism and reversing the bacterial-induced inflammation.

Validity of quantitative unspun urine microscopy, dipstick test leucocyte esterase and nitrite tests in rapidly diagnosing urinary tract infections

OBJECTIVES

Rapid diagnostic tests can screen out negative samples and can save valuable time and money. The study was conducted to assess the usefulness of leukocyte esterase, nitrate reductase and quantitative microscopic unspun urine wet mount examination in rapidly diagnosing urinary tract infections (UTI).

METHODS

Four hundred and fifty samples were tested by semi-quantitative culture on cysteine lactose electrolyte deficient medium, microscopic examination of unspun urine for significant pyuria, dipstick leucocyte esterase test (LET) and nitrite test (NT). Culture was used as gold standard to evaluate the performance of direct microscopy and dipstick tests.

RESULTS

Urine culture examination revealed significant bacteriuria (>10(5) cfu/ml) 98 (21.8%), in urine samples. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and the diagnostic odds ratio (DOR) of the dip-stick LET were 73.5%, 58.5%, 33.0%, 88.8%, and 3.9 respectively; those of the dip-stick NT were 57.1%, 78.7%, 42.7%, 86.8%, and 4.9 respectively; and those for microscopic significant pyuria detection were 68.4%, 60.8%, 32.7%, 87.3%, and 3.4 respectively. Highest sensitivity (95.9%), NPV (97.9%) and DOR (25.7) was obtained on combining microscopy and dip-stick LET and NT (either of them positive). This can potentially cut costs by 79%.

CONCLUSION

Quantitative unspun urine wet mount microscopy and dipstick tests for leucocyte esterase and nitrite test should be added into routine laboratory practices for faster diagnosis of UTI.

The efficacy of Echinacea in a 3-D tissue model of human airway epithelium

We evaluated the antirhinovirus efficacy of a standardized preparation of Echinacea purpurea (Echinaforce) in a 3-dimensional organotypic model of normal human airway epithelium (EpiAirway tissue). Individual replicate tissue samples, maintained as inserts in culture for 3 days or 3 weeks, were infected with rhinovirus type 1A (RV1A), Echinacea alone, a combination of the two, or medium only. None of the treatments affected the histological appearance or integrity of the tissues, all of which maintained a high level of cell viability and preservation of cilia. RV infection resulted in increased mucopolysaccharide inclusions in the goblet cells, but this feature was reversed by Echinacea treatment. This result was confirmed by measurements of mucin secretion, which was stimulated by RV but reversed by Echinacea, suggesting that mucus production during colds could be ameliorated by Echinacea. We did not find evidence of virus replication, although the RV-infected tissues secreted substantial amounts of the pro-inflammatory cytokines IL-6 and IL-8 (CXCL8), and this response was reversed by Echinacea treatment. These results confirmed previous findings derived from studies of bronchial and lung epithelial cell lines, namely, that RV infection results in a substantial inflammatory response in the absence of virus replication.

Higher moments of net proton multiplicity distributions at RHIC

We report the first measurements of the kurtosis (κ), skewness (S), and variance (σ2) of net-proton multiplicity (Np-Np) distributions at midrapidity for Au+Au collisions at square root of s(NN)=19.6, 62.4, and 200 GeV corresponding to baryon chemical potentials (μB) between 200 and 20 MeV. Our measurements of the products κσ2 and Sσ, which can be related to theoretical calculations sensitive to baryon number susceptibilities and long-range correlations, are constant as functions of collision centrality. We compare these products with results from lattice QCD and various models without a critical point and study the square root of s(NN) dependence of κσ2. From the measurements at the three beam energies, we find no evidence for a critical point in the QCD phase diagram for μB below 200 MeV.

Three-particle coincidence of the long range pseudorapidity correlation in high energy nucleus-nucleus collisions

We report the first three-particle coincidence measurement in pseudorapidity (Δη) between a high transverse momentum (p⊥) trigger particle and two lower p⊥ associated particles within azimuth |Δϕ|<0.7 in square root of s(NN)=200 GeV d+Au and Au+Au collisions. Charge ordering properties are exploited to separate the jetlike component and the ridge (long range Δη correlation). The results indicate that the correlation of ridge particles are uniform not only with respect to the trigger particle but also between themselves event by event in our measured Δη. In addition, the production of the ridge appears to be uncorrelated to the presence of the narrow jetlike component.

Group dynamics and social interaction in a South Asian online learning forum for faculty development of medical teachers

BACKGROUND

Group dynamics of online medical faculty development programs have not been analyzed and reported in literature. Knowledge of the types of content of posted messages will help to understand group dynamics and promote participation in an asynchronous learning environment. This paper assesses group dynamics and social interactivity in an online learning environment for medical teachers in the South Asian context.

METHODS

Participants of a medical education fellowship program conducted by the Foundation for Advancement of International Medical Education and Research (FAIMER) Regional Institute at Christian Medical College, Ludhiana (CMCL) in India interact on a listserv called the Mentoring-Learning Web (ML-Web). Monthly topics for online discussion are chosen by fellows through a standard tool called "multi-voting". Fellows volunteer to moderate sessions and direct the pace of the discussion. We analyzed the content and process of the discussion of one particular month. The emails were categorized as those that reflected cognitive presence (dealing with construction and exploration of knowledge), teacher presence (dealing with instructional material and learning resources), and social presence, or were administrative in nature. Social emails were further classified as: affective, cohesive and interactive.

RESULTS

Social emails constituted one-third of the total emails. Another one-quarter of the emails dealt with sharing of resources and teacher presence, while cognitive emails comprised 36.2% of the total. More than half of the social emails were affective, while a little less than one-third were cohesive.

CONCLUSION

Social posts are an inevitable part of online learning. These posts promote bonding between learners and contribute to better interaction and collaboration in online learning. Moderators should be aware of their presence and use them as tools to promote interactivity.