Crossing the Rift valley: using complete mitogenomes to infer the diversification and biogeographic history of ethiopian highlands Ptychadena (anura: Ptychadenidae).

The Ethiopian Highlands are considered a biodiversity hotspot, harboring a high number of endemic species. Some of the endemic species probably diversified in situ; this is, for example, the case of a monophyletic clade containing 12 known species of grass frogs of the genus Ptychadena. The different species occur at elevations ranging from 1,500 to above 3,400 m and constitute excellent models to study the process of diversification in the highlands as well as adaptations to high elevations. In this study, we sampled 294 specimens across the distribution of this clade and used complete mitogenomes and genome-wide SNP data to better understand how landscape features influenced the population structure and dispersal of these grass frogs across time and space. Using phylogenetic inference, population structure analyses, and biogeographic reconstructions, we found that the species complex probably first diversified on the south-east side of the Great Rift Valley. Later on, species dispersed to the north-west side, where more recent diversification occurred. We further demonstrate that Ptychadena species have dispersed across the Great Rift Valley at different times. Our analyses allowed for a more complete understanding of the contribution of geological events, biogeographic barriers and climatic changes as drivers of species diversification and adaptation in this important biogeographic region.

Applying multivariate statistics to discriminate uranium ore concentrate geolocations using (radio)chemical data in support of nuclear forensic investigations.

The application of Principal Components Analysis (PCA) to U and Th series gamma spectrometry data provides a discriminatory tool to help determine the provenance of illicitly recovered uranium ore concentrates (UOCs). The PCA is applied to a database of radiometric signatures from 19 historic UOCs from Australia, Canada, and the USA representing many uranium geological deposits. In this study a key process to obtain accurate radiometric data (gamma and alpha) is to digest the U-ores and UOCs using a lithium tetraborate fusion. Six UOCs from the same sample set were analysed 'blind' and compared against the database to identify their geolocation. These UOCs were all accurately linked to their correct geolocations which can aid the forensic laboratory in determining which further analytical techniques should be used to improve the confidence of the particular location.

Antimicrobial susceptibility of Propionibacterium acnes isolates from acne patients in Colombia.

BACKGROUND: The increasing prevalence of antimicrobial resistance in Propionibacterium acnes poses a significant challenge to successful treatment outcomes in acne patients. Although P. acnes resistance has been demonstrated throughout the world, no previous data regarding the antimicrobial susceptibility of P. acnes in Colombia are available. OBJECTIVES: The aim of this study was to determine the antimicrobial susceptibility of P. acnes to common antibiotics used in the treatment of acne in a Colombian population. METHODS: Samples were collected from facial acne lesions of 100 dermatology patients. All samples were cultured in anaerobic conditions, and final identification of isolates was performed. Isolates of P. acnes were then subjected to antimicrobial susceptibility tests using erythromycin, clindamycin, tetracycline, doxycycline, and minocycline. RESULTS: Propionibacterium acnes isolates resistant to erythromycin (35%), clindamycin (15%), doxycycline (9%), tetracycline (8%), and minocycline (1%) were observed. Isolates with cross-resistance were also observed (to erythromycin and clindamycin [12%] and to doxycycline and tetracycline [6%]). Overall, 46% of isolates taken from patients with a history of antibiotic use demonstrated resistance, whereas 29% of isolates taken from patients who had never used antibiotics demonstrated resistance. CONCLUSIONS: Antimicrobial resistance in P. acnes in this Colombian population has a lower prevalence than those reported in Europe and follows a similar pattern to findings elsewhere in Latin America. Resistance is demonstrated even in isolates from patients with no previous history of antibiotic use. Resistance to erythromycin is most commonly observed. Minocycline emerges as the most effective antibiotic.

Infliximab in the treatment of psoriasis in patients previously treated with etanercept.

BACKGROUND: Infliximab has shown promising results for the treatment of severe psoriasis and may be considered in patients who are unresponsive to conventional systemic and biologic therapy. METHODS: We conducted a retrospective study of 19 patients treated with infliximab for severe psoriasis who had previously been treated with etanercept. These patients had recalcitrant plaque psoriasis, which was unresponsive to multiple conventional systemic therapies before treatment with etanercept. Patients were evaluated for side effects and response to therapy. RESULTS: Nineteen patients (men = 14, women = 5) with a mean age of 50 years (range 34-83) were included in this study. Fourteen patients (74%) lost response after an initial improvement with etanercept, 3 had to discontinue because of insurance issues, and two failed to respond. Two of the 19 patients (11%) experienced infections while receiving etanercept. After the initiation of infliximab therapy, 17 of 19 patients (89%) showed initial improvement after 12 to 14 weeks, based on the physician's global assessment and body surface area done by a single physician. Ten patients (53%) required infliximab dose escalation to maintain control of their disease. Fifteen patients (79%) still receive infliximab therapy with favorable disease control. For these patients, the median time for treatment is 8 months (range 4-25). One patient experienced a minor infusion reaction and preferred not to continue after two infusions. Nine patients experienced minor infections. Two patients with known coronary artery disease died of myocardial infarction. LIMITATIONS: This was a retrospective study at a single practice site. CONCLUSIONS: Infliximab was effective in patients with psoriasis previously treated with etanercept, but the majority of patients required infusions every 6 weeks to maintain their continued response. In addition, the use of infliximab was associated with a possible increased incidence of adverse events.

Incidence and predictors of reinfection with Trichomonas vaginalis in HIV-infected women.

BACKGROUND AND OBJECTIVES: The presence of sexually transmitted infections (STIs) may facilitate transmission of HIV to uninfected partners. GOAL: To describe the incidence of reinfection with Trichomonas vaginalis in HIV-infected women and to assess predictors of reinfection. STUDY DESIGN: A retrospective cohort study using data abstracted from medical records of HIV-infected women with at least one diagnosis of trichomoniasis. RESULTS: Approximately one third (36%) of the study population was reinfected with T vaginalis during the follow-up period, with an incidence of 16.4 reinfections per 100 person years. Significant predictors of reinfection included history of another STI (hazard ratio, 1.52; 95% CI, 1.08-2.14) and becoming pregnant during the follow-up period (hazard ratio, 0.59; 95% CI, 0.39-0.87). CONCLUSIONS: There is a high rate of reinfection with T vaginalis in HIV-infected women. Further research that includes information on sexual partners should be conducted to better describe the reinfection patterns of trichomoniasis.