Renal Replacement Therapy for Acute Kidney Injury in Severe Alcohol-Associated Hepatitis as a Bridge to Transplant or Recovery.

BACKGROUND: Acute kidney injury is seen in approximately 30% of patients with severe alcohol-associated hepatitis (AH) and is associated with increased mortality. Controversy exists surrounding initiation of renal replacement therapy (RRT) in these patients, as most are ineligible for early transplantation. AIMS: The primary aim was to identify predictors of survival and identify patients who may benefit from RRT as a bridge to transplant or recovery. METHODS: A retrospective multicenter cohort of adult patients with AH, who received RRT, was developed, including patients from two North American and one European liver transplant centers. RESULTS: Fifty-five patients were included. Survival was 26/55 (47.3%) at 30 days, 17/55 (30.9%) at 3 months, and 15/55 (27.2%) at 6 months. Of those who survived 6 months, 2/15 (13.3%) received simultaneous liver and kidney transplantation, 11/15 (73.3%) had spontaneous recovery of kidney function, and 2/15 (13.3%) remained on RRT. Of patients who survived at least 3 months, 8/17 (47%) completed addiction treatment. Predictors of mortality were pre-RRT MELD (OR 1.10, 1.02-1.19) and pre-RRT MELD-Na (OR 1.14, 1.03-1.27). Pre-RRT MELD-Na < 35 was associated with lower 6-month mortality (OR 0.23, 0.06 - 0.81). Of patients with pre-RRT MELD-Na < 35, 50% survived 6 months compared to 18% of patients with pre-RRT MELD-Na ≥ 35. CONCLUSIONS: Although RRT has a limited role in patients with decompensated cirrhosis, ineligible for transplant, it may be used in select patients with AH. This may allow for spontaneous recovery with alcohol abstinence or completion of addiction treatment prior to transplant.

The γ-Protocadherins Regulate the Survival of GABAergic Interneurons during Developmental Cell Death.

Inhibitory interneurons integrate into developing circuits in specific ratios and distributions. In the neocortex, inhibitory network formation occurs concurrently with the apoptotic elimination of a third of GABAergic interneurons. The cell surface molecules that select interneurons to survive or die are unknown. Here, we report that members of the clustered Protocadherins (cPCDHs) control GABAergic interneuron survival during developmentally-regulated cell death. Conditional deletion of the gene cluster encoding the γ-Protocadherins (Pcdhgs) from developing GABAergic neurons in mice of either sex causes a severe loss of inhibitory populations in multiple brain regions and results in neurologic deficits such as seizures. By focusing on the neocortex and the cerebellar cortex, we demonstrate that reductions of inhibitory interneurons result from elevated apoptosis during the critical postnatal period of programmed cell death (PCD). By contrast, cortical interneuron (cIN) populations are not affected by removal of Pcdhgs from pyramidal neurons or glial cells. Interneuron loss correlates with reduced AKT signaling in Pcdhg mutant interneurons, and is rescued by genetic blockade of the pro-apoptotic factor BAX. Together, these findings identify the PCDHGs as pro-survival transmembrane proteins that select inhibitory interneurons for survival and modulate the extent of PCD. We propose that the PCDHGs contribute to the formation of balanced inhibitory networks by controlling the size of GABAergic interneuron populations in the developing brain.SIGNIFICANCE STATEMENT A pivotal step for establishing appropriate excitatory-inhibitory ratios is adjustment of neuronal populations by cell death. In the mouse neocortex, a third of GABAergic interneurons are eliminated by BAX-dependent apoptosis during the first postnatal week. Interneuron cell death is modulated by neural activity and pro-survival pathways but the cell-surface molecules that select interneurons for survival or death are unknown. We demonstrate that members of the cadherin superfamily, the clustered γ-Protocadherins (PCDHGs), regulate the survival of inhibitory interneurons and the balance of cell death. Deletion of the Pcdhgs in mice causes inhibitory interneuron loss in the cortex and cerebellum, and leads to motor deficits and seizures. Our findings provide a molecular basis for controlling inhibitory interneuron population size during circuit formation.

Fabry disease in two brothers with proteinuria: A case report and Fabry disease review
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Fabry disease is an X-linked lysosomal storage disease characterized by alpha-galactosidase A (α-Gal A) enzyme deficiency. It can present with a variety of clinical manifestations ranging from complaints of extremity numbness and tingling to end-stage renal disease, cardiovascular disease, or stroke. Although it causes proteinuria and chronic kidney disease, it is often not included in the differential diagnosis of a young adult who presents with proteinuria. We describe the histories of two brothers who received a diagnosis of Fabry disease after one underwent a kidney biopsy. The diagnosis had profound implications for both individuals and their family. These cases and the accompanying review of kidney manifestations of Fabry disease demonstrate why the differential diagnosis of a young male with proteinuria and family history of kidney disease must include Fabry disease and why nephrologists should consider α-Gal A enzyme deficiency screening in the evaluation of male patients. Additionally, they highlight the importance of obtaining a kidney biopsy when the etiology of kidney disease is unknown.
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Bacterial and archaeal diversity in two hot spring microbial mats from the geothermal region of Tengchong, China.

We investigated the bacterial and archaeal diversity in two hot spring microbial mats from the geothermal region of Tengchong in the Yunnan Province, China, using direct molecular analyses. The Langpu (LP) laminated mat was found by the side of a boiling pool with temperature of 60-65 °C and a pH of 8.5, while the Tengchong (TC) streamer mat consisted of white streamers in a slightly acidic (pH 6.5) hot pool outflow with a temperature of 72 °C. Four 16S rRNA gene clone libraries were constructed and restriction enzyme analysis of the inserts was used to identify unique sequences and clone frequencies. From almost 200 clones screened, 55 unique sequences were retrieved. Phylogenetic analysis showed that the LP mat consisted of a diverse bacterial population [Cyanobacteria, Chloroflexi, Chlorobia, Nitrospirae, 'Deinococcus-Thermus', Proteobacteria (alpha, beta and delta subdivisions), Firmicutes, Bacteroidetes and Actinobacteria], while the archaeal population was dominated by methanogenic Euryarchaeota and Crenarchaeota. In contrast, the TC streamer mat consisted of a bacterial population dominated by Aquificae, while the archaeal population also contained Korarchaeota as well as Crenarchaeota and methanogenic Euryarchaeota. These mats harboured clone sequences affiliated to unidentified lineages, suggesting that they are a potential source for discovering novel bacteria and archaea.

Asymptomatic Pyuria as a Prognostic Biomarker in Autosomal Dominant Polycystic Kidney Disease.

Background: Autosomal dominant polycystic kidney disease (ADPKD) has phenotypic variability only partially explained by established biomarkers that do not readily assess pathologically important factors of inflammation and kidney fibrosis. We evaluated asymptomatic pyuria (AP), a surrogate marker of inflammation, as a biomarker for disease progression. Methods: We performed a retrospective cohort study of adult patients with ADPKD. Patients were divided into AP and no pyuria (NP) groups. We evaluated the effect of pyuria on kidney function and kidney volume. Longitudinal models evaluating kidney function and kidney volume rate of change with respect to incidences of AP were created. Results: There were 687 included patients (347 AP, 340 NP). The AP group had more women (65% versus 49%). Median ages at kidney failure were 86 and 80 years in the NP and AP groups (log rank, P=0.49), respectively, for patients in Mayo Imaging Class (MIC) 1A-1B as compared with 59 and 55 years for patients in MIC 1C-1D-1E (log rank, P=0.02), respectively. Compared with the NP group, the rate of kidney function (ml/min per 1.73 m2 per year) decline shifted significantly after detection of AP in the models, including all patients (-1.48; P<0.001), patients in MIC 1A-1B (-1.79; P<0.001), patients in MIC 1C-1D-1E (-1.18; P<0.001), and patients with PKD1 (-1.04; P<0.001). Models evaluating kidney volume rate of growth showed no change after incidence of AP as compared with the NP group. Conclusions: AP is associated with kidney failure and faster kidney function decline irrespective of the ADPKD gene, cystic burden, and cystic growth. These results support AP as an enriching prognostic biomarker for the rate of disease progression.

Microbial biogeography of six salt lakes in Inner Mongolia, China, and a salt lake in Argentina.

We used cultivation-independent methods to investigate the prokaryotic biogeography of the water column in six salt lakes in Inner Mongolia, China, and a salt lake in Argentina. These lakes had different salt compositions and pH values and were at variable geographic distances, on both local and intercontinental scales, which allowed us to explore the microbial community composition within the context of both contemporary environmental conditions and geographic distance. Fourteen 16S rRNA gene clone libraries were constructed, and over 200 16S rRNA gene sequences were obtained. These sequences were used to construct biotic similarity matrices, which were used in combination with environmental similarity matrices and a distance matrix in the Mantel test to discover which factors significantly influenced biotic similarity. We showed that archaeal biogeography was influenced by contemporary environmental factors alone (Na+, CO3(2-), and HCO3(-) ion concentrations; pH; and temperature). Bacterial biogeography was influenced both by contemporary environmental factors (Na+, Mg2+, and HCO3(-) ion concentrations and pH) and by geographic distance.

Autoimmune receptor encephalitis in mice induced by active immunization with conformationally stabilized holoreceptors.

Autoimmunity to membrane proteins in the central nervous system has been increasingly recognized as a cause of neuropsychiatric disease. A key recent development was the discovery of autoantibodies to N-methyl-d-aspartate (NMDA) receptors in some cases of encephalitis, characterized by cognitive changes, memory loss, and seizures that could lead to long-term morbidity or mortality. Treatment approaches and experimental studies have largely focused on the pathogenic role of these autoantibodies. Passive antibody transfer to mice has provided useful insights but does not produce the full spectrum of the human disease. Here, we describe a de novo autoimmune mouse model of anti-NMDA receptor encephalitis. Active immunization of immunocompetent mice with conformationally stabilized, native-like NMDA receptors induced a fulminant encephalitis, consistent with the behavioral and pathologic characteristics of human cases. Our results provide evidence for neuroinflammation and immune cell infiltration as components of the autoimmune response in mice. Use of transgenic mice indicated that mature T cells and antibody-producing cells were required for disease induction. This active immunization model may provide insights into disease induction and a platform for testing therapeutic approaches.

Sequence analysis of an Archaeal virus isolated from a hypersaline lake in Inner Mongolia, China.

BACKGROUND: We are profoundly ignorant about the diversity of viruses that infect the domain Archaea. Less than 100 have been identified and described and very few of these have had their genomic sequences determined. Here we report the genomic sequence of a previously undescribed archaeal virus. RESULTS: Haloarchaeal strains with 16S rRNA gene sequences 98% identical to Halorubrum saccharovorum were isolated from a hypersaline lake in Inner Mongolia. Two lytic viruses infecting these were isolated from the lake water. The BJ1 virus is described in this paper. It has an icosahedral head and tail morphology and most likely a linear double stranded DNA genome exhibiting terminal redundancy. Its genome sequence has 42,271 base pairs with a GC content ofapproximately 65 mol%. The genome of BJ1 is predicted to encode 70 ORFs, including one for a tRNA. Fifty of the seventy ORFs had no identity to data base entries; twenty showed sequence identity matches to archaeal viruses and to haloarchaea. ORFs possibly coding for an origin of replication complex, integrase, helicase and structural capsid proteins were identified. Evidence for viral integration was obtained. CONCLUSION: The virus described here has a very low sequence identity to any previously described virus. Fifty of the seventy ORFs could not be annotated in any way based on amino acid identities with sequences already present in the databases. Determining functions for ORFs such as these is probably easier using a simple virus as a model system.

Diversity of cultivated aerobic poly-hydrolytic bacteria in saline alkaline soils.

Alkaline saline soils, known also as "soda solonchaks", represent a natural soda habitat which differs from soda lake sediments by higher aeration and lower humidity. The microbiology of soda soils, in contrast to the more intensively studied soda lakes, remains poorly explored. In this work we investigate the diversity of culturable aerobic haloalkalitolerant bacteria with various hydrolytic activities from soda soils at different locations in Central Asia, Africa, and North America. In total, 179 pure cultures were obtained by using media with various polymers at pH 10 and 0.6 M total Na+. According to the 16S rRNA gene sequence analysis, most of the isolates belonged to Firmicutes and Actinobacteria. Most isolates possessed multiple hydrolytic activities, including endoglucanase, xylanase, amylase and protease. The pH profiling of selected representatives of actinobacteria and endospore-forming bacteria showed, that the former were facultative alkaliphiles, while the latter were mostly obligate alkaliphiles. The hydrolases of selected representatives from both groups were active at a broad pH range from six to 11. Overall, this work demonstrates the presence of a rich hydrolytic bacterial community in soda soils which might be explored further for production of haloalkalistable hydrolases.

Sleep-dependent plasticity requires cortical activity.

Recent findings in humans and animals suggest that sleep promotes synaptic plasticity, but the underlying mechanisms have not been identified. We have demonstrated recently an important role for sleep in ocular dominance (OD) plasticity, a classic form of in vivo cortical remodeling triggered by monocular deprivation (MD) during a critical period of development. The mechanisms responsible for the effects of sleep on OD plasticity are unknown but may depend on neuronal activity in the sleeping brain. We investigated the role of cortical activity in sleep-dependent plasticity by reversibly inactivating the sleeping visual cortex (V1) after a period of MD. Critical period cats were bilaterally implanted with cannulas in V1 and standard EEG/EMG electrodes for polysomnographic recording. After a period of MD, visual cortices were infused with the sodium channel blocker lidocaine in vehicle or vehicle only during sleep. A third group of cats served as sham controls and were infused with lidocaine outside of V1 (into the CSF). Both optical imaging of intrinsic cortical signals and microelectrode recordings showed that OD plasticity was significantly reduced in cats whose visual cortices were reversibly silenced during sleep. These findings demonstrate that the mechanisms governing this form of sleep-dependent plasticity require cortical activity. They provide an important insight into how sleep modifies synaptic circuitry by narrowing the range of possible candidate mechanisms to those that are activity dependent.

Statistical tools and control of internal lubricant content of inhalation grade HPMC capsules during manufacture.

The internal lubricant content (ILC) of inhalation grade HPMC capsules is a key factor to ensure good powder release when the patient inhales a medicine from a dry powder inhaler (DPI). Powder release from capsules has been shown to be influenced by the ILC. The characteristics used to measure this are the emitted dose, fine particle fraction and mass median aerodynamic diameter. In addition the ILC level is critical for capsule shell manufacture because it is an essential part of the process that cannot work without it. An experiment has been applied to the manufacture of inhalation capsules with the required ILC. A full factorial model was used to identify the controlling factors and from this a linear model has been proposed to improve control of the process.

Evaluating the sensitivity, reproducibility and flexibility of a method to test hard shell capsules intended for use in dry powder inhalers.

Pharmaceutical tests for hard shell capsules are designed for orally administered capsules. The use of capsules in dry powder inhalers is widespread and increasing and therefore more appropriate tests are required to ensure quality and determine if these capsules are fit for purpose. This study aims to determine the flexibility, reproducibility and sensitivity of a quantitative method that is designed to evaluate the puncture characteristics of different capsule shell formulations under different climatic conditions. A puncture testing method was used to generate force displacement curves for five capsule formulations that were stored and tested at two different temperatures (5°C and 19°C). Force-displacement puncture profiles were reproducible for individual capsule shell formulations. The methodology was able to discriminate between capsules produced using different primary materials i.e. gelatin versus hypromellose, as well as more minor changes to capsule formulation i.e. different material grades and excipients. Reduced temperature increased the forces required for capsule puncture however further work is required to confirm its significance. Results indicate the method provides a reproducible and sensitive means of evaluating capsule puncture. Future studies should validate the methodology at different test sites, using different operators and with different capsule shell formulations.

Namib Desert dune/interdune transects exhibit habitat-specific edaphic bacterial communities.

The sand dunes and inter-dune zones of the hyper-arid central Namib Desert represent heterogeneous soil habitats. As little is known about their indigenous edaphic bacterial communities, we aimed to evaluate their diversity and factors of assembly and hypothesized that soil physicochemistry gradients would strongly shape dune/interdune communities. We sampled a total of 125 samples from 5 parallel dune/interdune transects and characterized 21 physico-chemical edaphic parameters coupled with 16S rRNA gene bacterial community fingerprinting using T-RFLP and 454 pyrosequencing. Multivariate analyses of T-RFLP data showed significantly different bacterial communities, related to physico-chemical gradients, in four distinct dune habitats: the dune top, slope, base and interdune zones. Pyrosequencing of 16S rRNA gene amplicon sets showed that each dune zone presented a unique phylogenetic profile, suggesting a high degree of environmental selection. The combined results strongly infer that habitat filtering is an important factor shaping Namib Desert dune bacterial communities, with habitat stability, soil texture and mineral and nutrient contents being the main environmental drivers of bacterial community structures.

The development of a sensitive methodology to characterise hard shell capsule puncture by dry powder inhaler pins.

In order for hard-shell capsules to function effectively as drug reservoirs in dry powder inhalers, the capsule must be punctured with sharpened pins to release the powdered medicament upon inspiration. Capsule performance in this setting is poorly understood. This study aims to develop a methodology to characterise hard shell capsule penetration by needles from commercial dry powder inhalers, to determine whether changes to capsule materials impact on their performance. Two pin types from two commercial dry powder inhalers were mounted in a material-testing machine, equipped with a 500 N load cell. A stainless steel bush was used to secure a capsule directly below the steel pin. Hypromellose (n=10) and gelatin capsules (n=10) were conditioned in 'normal' or low humidity conditions and were subsequently punctured with both types of pin. Each puncture event was recorded on a load-displacement curve. The force required for puncture was 2.82±0.26 N for hypromellose capsules and 4.54±0.26 N for gelatin capsules, stored in normal humidity. Different capsule materials possessed distinguishable signature profiles but repeated force-displacement profiles were highly reproducible i.e. intra-individual variability was minimal. A rapid, robust yet sensitive methodology has therefore been developed that is able to characterise hard shell capsule materials based on the puncture performance.

Bacillus locisalis sp. nov., a new haloalkaliphilic species from hypersaline and alkaline lakes of China, Kenya and Tanzania.

A polyphasic taxonomic study was performed on seven Bacillus-like bacteria isolated from three hypersaline and alkaline lakes located in China, Kenya and Tanzania. All strains were moderately halophilic and alkaliphilic, Gram positive, motile rods. The DNA G+C content from the seven isolates ranged from 42.2 to 43.4mol% and their major fatty acid was anteiso-C(15:0). Strain CG1(T), selected as representative strain of the isolates, possesses meso-diaminopimelic acid in the cell wall peptidoglycan, MK-7 as the predominant menaquinone and diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine as the major polar lipids. Comparative 16S rRNA gene sequence analysis indicated that the isolates belonged to the genus Bacillus. The seven isolates shared 97.7-99.9% 16S rRNA gene sequence similarity, and formed a branch that was distinct from the type strains of the recognized species of the genus Bacillus. They were most closely related to Bacillus agaradhaerens DSM 8721(T) (92.6-93.8% 16S rRNA sequence similarity). DNA-DNA hybridization values between the seven isolates were 85-100%. According to the polyphasic characterization, the strains represent a novel species, for which the name Bacillus locisalis sp. nov. is proposed. The type strain is CG1(T) (CCM 7370(T)=CECT 7152(T)=CGMCC 1.6286(T)=DSM 18085(T)).

Improved method for direct screening of true lipase-producing microorganisms with particular emphasis on alkaline conditions.

A rapid and effective method for direct detection, selection and testing of microorganisms able to produce both cell-bound and extracellular true lipases is described. The method is based on formation of clearance zones on turbid solid media with emulsified olive oil around or under the colonies, cell fractions or culture supernatant of lipase-producing organisms. The method was successfully applied for the screening and isolation of microorganisms producing alkaline lipases.

Identification of eukaryotic open reading frames in metagenomic cDNA libraries made from environmental samples.

Here we describe the application of metagenomic technologies to construct cDNA libraries from RNA isolated from environmental samples. RNAlater (Ambion) was shown to stabilize RNA in environmental samples for periods of at least 3 months at -20 degrees C. Protocols for library construction were established on total RNA extracted from Acanthamoeba polyphaga trophozoites. The methodology was then used on algal mats from geothermal hot springs in Tengchong county, Yunnan Province, People's Republic of China, and activated sludge from a sewage treatment plant in Leicestershire, United Kingdom. The Tenchong libraries were dominated by RNA from prokaryotes, reflecting the mainly prokaryote microbial composition. The majority of these clones resulted from rRNA; only a few appeared to be derived from mRNA. In contrast, many clones from the activated sludge library had significant similarity to eukaryote mRNA-encoded protein sequences. A library was also made using polyadenylated RNA isolated from total RNA from activated sludge; many more clones in this library were related to eukaryotic mRNA sequences and proteins. Open reading frames (ORFs) up to 378 amino acids in size could be identified. Some resembled known proteins over their full length, e.g., 36% match to cystatin, 49% match to ribosomal protein L32, 63% match to ribosomal protein S16, 70% to CPC2 protein. The methodology described here permits the polyadenylated transcriptome to be isolated from environmental samples with no knowledge of the identity of the microorganisms in the sample or the necessity to culture them. It has many uses, including the identification of novel eukaryotic ORFs encoding proteins and enzymes.

Caldalkalibacillus thermarum gen. nov., sp. nov., a novel alkalithermophilic bacterium from a hot spring in China.

A thermophilic, alkaliphilic and catalase-positive bacterium, designated strain HA6(T), was isolated from a hot spring in China. The strain was aerobic and chemo-organotrophic and grew optimally at 60 degrees C, pH 8.5 and 1.5 % (w/v) NaCl. The cells were Gram-positive rods, forming single terminal endospores. The predominant cellular fatty acids were iso-C(15 : 0) and iso-C(17 : 0). The cell-wall peptidoglycan contained meso-diaminopimelic acid. The genomic DNA G+C content was 45.2 mol%. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that strain HA6(T) formed a distinct lineage within the family Bacillaceae and was most closely related to Bacillus horti K13(T) and Bacillus smithii DSM 4216(T), with sequence similarities of 91.8 and 93.1 %, respectively. On the basis of its physiological and molecular properties, strain HA6(T) should be placed in a novel genus and species, for which the name Caldalkalibacillus thermarum gen. nov., sp. nov. is proposed. The type strain of Caldalkalibacillus thermarum is strain HA6(T) (=CGMCC 1.4242(T)=JCM 13486(T)).