An oligotrophic deep-subsurface community dependent on syntrophy is dominated by sulfur-driven autotrophic denitrifiers

Subsurface lithoautotrophic microbial ecosystems (SLiMEs) under oligotrophic conditions are typically supported by H₂. Methanogens and sulfate reducers, and the respective energy processes, are thought to be the dominant players and have been the research foci. Recent investigations showed that, in some deep, fluid-filled fractures in the Witwatersrand Basin, South Africa, methanogens contribute <5% of the total DNA and appear to produce sufficient CH₄ to support the rest of the diverse community. This paradoxical situation reflects our lack of knowledge about the in situ metabolic diversity and the overall ecological trophic structure of SLiMEs. Here, we show the active metabolic processes and interactions in one of these communities by combining metatranscriptomic assemblies, metaproteomic and stable isotopic data, and thermodynamic modeling. Dominating the active community are four autotrophic β-proteobacterial genera that are capable of oxidizing sulfur by denitrification, a process that was previously unnoticed in the deep subsurface. They co-occur with sulfate reducers, anaerobic methane oxidizers, and methanogens, which each comprise <5% of the total community. Syntrophic interactions between these microbial groups remove thermodynamic bottlenecks and enable diverse metabolic reactions to occur under the oligotrophic conditions that dominate in the subsurface. The dominance of sulfur oxidizers is explained by the availability of electron donors and acceptors to these microorganisms and the ability of sulfur-oxidizing denitrifiers to gain energy through concomitant S and H₂ oxidation. We demonstrate that SLiMEs support taxonomically and metabolically diverse microorganisms, which, through developing syntrophic partnerships, overcome thermodynamic barriers imposed by the environmental conditions in the deep subsurface

The Functioning of the Drosophila CPEB Protein Orb Is Regulated by Phosphorylation and Requires Casein Kinase 2 Activity

The Orb CPEB protein regulates translation of localized mRNAs in Drosophila ovaries. While there are multiple hypo- and hyperphosphorylated Orb isoforms in wild type ovaries, most are missing in orbF303, which has an amino acid substitution in a buried region of the second RRM domain. Using a proteomics approach we identified a candidate Orb kinase, Casein Kinase 2 (CK2). In addition to being associated with Orb in vivo, we show that ck2 is required for orb functioning in gurken signaling and in the autoregulation of orb mRNA localization and translation. Supporting a role for ck2 in Orb phosphorylation, we find that the phosphorylation pattern is altered when ck2 activity is partially compromised. Finally, we show that the Orb hypophosphorylated isoforms are in slowly sedimenting complexes that contain the translational repressor Bruno, while the hyperphosphorylated isoforms assemble into large complexes that co-sediment with polysomes and contain the Wisp poly(A) polymerase

Spread of artemisinin resistance in Plasmodium falciparum malaria.

BACKGROUND: Artemisinin resistance in Plasmodium falciparum has emerged in Southeast Asia and now poses a threat to the control and elimination of malaria. Mapping the geographic extent of resistance is essential for planning containment and elimination strategies. METHODS: Between May 2011 and April 2013, we enrolled 1241 adults and children with acute, uncomplicated falciparum malaria in an open-label trial at 15 sites in 10 countries (7 in Asia and 3 in Africa). Patients received artesunate, administered orally at a daily dose of either 2 mg per kilogram of body weight per day or 4 mg per kilogram, for 3 days, followed by a standard 3-day course of artemisinin-based combination therapy. Parasite counts in peripheral-blood samples were measured every 6 hours, and the parasite clearance half-lives were determined. RESULTS: The median parasite clearance half-lives ranged from 1.9 hours in the Democratic Republic of Congo to 7.0 hours at the Thailand-Cambodia border. Slowly clearing infections (parasite clearance half-life >5 hours), strongly associated with single point mutations in the "propeller" region of the P. falciparum kelch protein gene on chromosome 13 (kelch13), were detected throughout mainland Southeast Asia from southern Vietnam to central Myanmar. The incidence of pretreatment and post-treatment gametocytemia was higher among patients with slow parasite clearance, suggesting greater potential for transmission. In western Cambodia, where artemisinin-based combination therapies are failing, the 6-day course of antimalarial therapy was associated with a cure rate of 97.7% (95% confidence interval, 90.9 to 99.4) at 42 days. CONCLUSIONS: Artemisinin resistance to P. falciparum, which is now prevalent across mainland Southeast Asia, is associated with mutations in kelch13. Prolonged courses of artemisinin-based combination therapies are currently efficacious in areas where standard 3-day treatments are failing. (Funded by the U.K. Department of International Development and others; ClinicalTrials.gov number, NCT01350856.)

Osteochondral Allograft Implantation Using the Smith–Peterson (Anterior) Approach for Chondral Lesions of the Femoral Head

Management of chondral lesions of the femoral head can be challenging. Previously described approaches include arthroscopic surgery for small lesions and open surgical dislocation for larger lesions. In 2001, Ganz popularized the trochanteric flip osteotomy for surgical dislocation, and this remains the workhorse for treatment of large chondral lesions. However, by using a Smith–Peterson (direct anterior) approach and a femoral head allograft, large lesions may be treated while avoiding both trochanteric osteotomy and donor-site morbidity. We present our technique using a Smith–Peterson approach and osteochondral implantation of fresh femoral head allograft for surgical treatment of a femoral head chondral lesion

Microfracture in Hip Arthroscopy. Keep It Simple!

Despite all the advances in hip arthroscopy, microfracture is still the workhorse for treating focal and full-thickness cartilage lesions. The success of this treatment is owed to its reliability and simplicity. Given the structure of the hip joint, however, there are challenges to this procedure using a conventional microfracture pick. This note presents our current and preferred microfracture technique using a curve drill guide and flexible drill. This method offers greater range of access to different regions of the joint with ease, thus ensuring a reproducible and quicker procedure with less risk

Do Not Take for Granted! The Art of Elevating the Capsule in Hip Arthroscopy: A Stepwise Approach

Different techniques have been described to close or plicate the capsule. To perform these procedures, however, the capsule must be preserved, a consideration unfortunately often overlooked. This Technical Note describes in a stepwise manner the initial capsular management necessary to preserve the capsule for further procedures such as closure or plication. Level of Evidence: I (hip), II (impingement, labrum, other)

Localization of Breast Cancer Resistance Protein (BCRP) in Microvessel Endothelium of Human Control and Epileptic Brain

Purpose: Breast cancer resistance protein (BCRP) is a half adenosine triphosphate (ATP)-binding cassette (ABC) transporter expressed on cellular membranes and included in the group of multidrug resistant (MDR)-related proteins. Recently, upregulation of different MDR proteins has been shown in human epilepsy-associated conditions. This study investigated the expression and cellular distribution of BCRP in human control and epileptic brain, including a large number of both neoplastic and nonneoplastic specimens from patients with chronic pharmacoresistant epilepsy. Methods: Several epileptogenic pathologies, such as hippocampal sclerosis (HS), focal cortical dysplasia (FCD), dysembryoplastic neuroepithelial tumor, oligodendroglioma astrocytoma, and glioblastoma multiforme were studied by using Western blot and immunocytochemistry. Results: With Western blot, we could demonstrate the presence of BCRP in both normal and epileptic human brain tissue. In contrast to P-glycoprotein (P-gp) and multidrug resistance-associated protein (MRP) 2, BCRP expression levels did not change in tissue from patients with HS, compared with control hippocampus. No BCRP immunoreactivity was observed in glial or neuronal cells, including reactive astrocytes and dysplastic neurons in FCD. BCRP expression was, however, increased in tumor brain tissue. Immunocytochemistry demonstrated that BCRP was exclusively located in blood vessels and was highly expressed at the luminal cell surface and in newly formed tumor capillaries. This localization closely resembles that of P-gp. The higher expression observed in astrocytomas by Western blot analysis was related to the higher vascular density within the tumor tissue. Conclusions: These results indicate a constitutive expression of BCRP in human endothelial cells, representing an important barrier against drug access to the brain. In particular, the strong BCRP expression in the microvasculature of epileptogenic brain tumors could critically influence the bioavailability of drugs within the tumor and contribute to pharmacoresistanc