Simulated Micro-, Lunar, and Martian Gravities on Earth-Effects on Escherichia coli Growth, Phenotype, and Sensitivity to Antibiotics.

Bacterial behavior has been studied under microgravity conditions, but very little is known about it under lunar and Martian gravitational regimes. An Earth-based approach was designed and implemented using inclined clinostats and an in-house-developed code to determine the optimal clinorotation angular speed for bacterial liquid cultures of 5 RPM. With this setup, growth dynamics, phenotypic changes, and sensitivity to antibiotics (minimum inhibitory concentration (MIC) of two different classes of antibiotics) for three Escherichia coli strains (including uropathogenic) were examined under simulated micro-, lunar, and Martian gravities. The results included increased growth under simulated micro- and lunar gravities for some strains, and higher concentrations of antibiotics needed under simulated lunar gravity with respect to simulated micro- and Martian gravities. Clinostat-produced results can be considered suggestive but not determinative of what might be expected in altered gravity, as there is still a need to systematically verify these simulation devices' ability to accurately replicate phenomena observed in space. Nevertheless, this approach serves as a baseline to start interrogating key cellular and molecular aspects relevant to microbial processes on the lunar and Martian surfaces.

A Distinct Brain-Gut-Microbiome Profile Exists for Females with Obesity and Food Addiction.

BACKGROUND: Alterations in brain-gut-microbiome interactions have been implicated as an important factor in obesity. This study aimed to explore the relationship between food addiction (FA) and the brain-gut-microbiome axis, using a multi-omics approach involving microbiome data, metabolomics, and brain imaging. METHODS: Brain magnetic resonance imaging was obtained in 105 females. FA was defined by using the Yale Food Addiction Scale. Fecal samples were collected for sequencing and metabolomics. Statistical analysis was done by using multivariate analyses and machine learning algorithms. RESULTS: Of the females with obesity, 33.3% exhibited FA as compared with 5.3% and 0.0% of females with overweight and normal BMI, respectively (P = 0.0001). Based on a multilevel sparse partial least square discriminant analysis, there was a difference in the gut microbiome of females with FA versus those without. Differential abundance testing showed Bacteroides, Megamonas, Eubacterium, and Akkermansia were statistically associated with FA (q < 0.05). Metabolomics showed that indolepropionic acid was inversely correlated with FA. FA was also correlated with increased connectivity within the brain's reward network, specifically between the intraparietal sulcus, brain stem, and putamen. CONCLUSIONS: This is the first study to examine FA along the brain-gut-microbiome axis and it supports the idea of targeting the brain-gut-microbiome axis for the treatment of FA and obesity.

Machine Learning-based Development and Validation of a Scoring System for Screening High-Risk Esophageal Varices.

BACKGROUND & AIMS: Many patients with cirrhosis who undergo esophagogastroduodenoscopy (EGD) screening for esophageal varices (EVs) are found to have no or only small EVs. Endoscopic screening for EVs is therefore a potentially deferrable procedure that increases patient risk and healthcare cost. We developed and validated a scoring system, based on readily-available data, to reliably identify patients with EVs that need treatment. METHODS: We collected data from 238 patients with cirrhosis undergoing screening EGD from January 2016 through December 2017 at 3 separate hospitals in Los Angeles (training cohort). We abstracted data on patient sex, age, race/ethnicity, platelet counts, and levels of hemoglobin, serum sodium, aspartate aminotransferase, alanine aminotransferase, total bilirubin, international normalized ratio, albumin, urea nitrogen, and creatinine. We also included etiology of cirrhosis, presence of ascites, and presence of hepatic encephalopathy. We used a random forest algorithm to identify factors significantly associated with the presence of EVs and varices needing treatment (VNT) and calculated area under the receiver operating characteristic curve (AUROC). We called the resulting formula the EVendo score. We tested the accuracy of EVendo in a prospective study of 109 patients undergoing screening EGDs at the same medical centers from January 2018 through December 2018 (validation cohort). RESULTS: We developed an algorithm that identified patients with EVs and VNT based on international normalized ratio, level of aspartate aminotransferase, platelet counts, urea nitrogen, hemoglobin, and presence of ascites. The EVendo score identified patients with EVs in the training set with an AUROC of 0.84, patients with EVs in the validation set with and AUROC of 0.82, and EVs in patients with cirrhosis Child-Turcotte-Pugh class A (n = 235) with an AUROC of 0.81. The score identified patients with VNT in the training set with an AUROC of 0.74, VNT in the validation set with and AUROC of 0.75, and VNT in patients with cirrhosis Child-Turcotte-Pugh class A with and AUROC of 0.75. An EVendo score below 3.90 would have spared 30.5% patients from EGDs, missing only 2.8% of VNT. The same cutoff would have spared 40.0% of patients with Child-Turcotte-Pugh class A cirrhosis from EGDs, missing only 1.1% of VNT. CONCLUSIONS: We algorithmically developed a formula, called the EVendo score, that can be used to predict EVs and VNT based on readily available data in patients with cirrhosis. This score could help patients at low risk for VNT avoid unnecessary EGDs.

The Brain-Gut-Microbiome Axis.

Preclinical and clinical studies have shown bidirectional interactions within the brain-gut-microbiome axis. Gut microbes communicate to the central nervous system through at least 3 parallel and interacting channels involving nervous, endocrine, and immune signaling mechanisms. The brain can affect the community structure and function of the gut microbiota through the autonomic nervous system, by modulating regional gut motility, intestinal transit and secretion, and gut permeability, and potentially through the luminal secretion of hormones that directly modulate microbial gene expression. A systems biological model is proposed that posits circular communication loops amid the brain, gut, and gut microbiome, and in which perturbation at any level can propagate dysregulation throughout the circuit. A series of largely preclinical observations implicates alterations in brain-gut-microbiome communication in the pathogenesis and pathophysiology of irritable bowel syndrome, obesity, and several psychiatric and neurologic disorders. Continued research holds the promise of identifying novel therapeutic targets and developing treatment strategies to address some of the most debilitating, costly, and poorly understood diseases.

Pseudocirrhosis in a Patient with New-Onset Dysphagia and History of Ovarian Carcinoma.

Pseudocirrhosis is an infrequently reported clinico-radiologic complication that primarily occurs in a subset of patients with a history of breast carcinoma metastatic to the liver that has been treated with systemic chemotherapy, particularly capecitabine, gemcitabine, trastuzumab, and/or paclitaxel. Even less common are cases of pseudocirrhosis secondary to other (i.e., non-breast) carcinomas. We describe a 43-year-old woman with a history of metastatic ovarian carcinoma treated several years prior with systemic chemotherapy who presented with progressive dysphagia and was found to have gastroesophageal junction adenocarcinoma and, incidentally, pseudocirrhosis.

Roux-en-Y gastric bypass in the treatment of non-classic congenital adrenal hyperplasia due to 11-hydroxylase deficiency.

Non-classic adrenal hyperplasia (NCAH) has been associated with insulin resistance (IR). Therapies such as metformin, thiazolidinediones and lifestyle alterations improve IR and also ameliorate the biochemical and clinical abnormalities of NCAH, much as they do in polycystic ovarian syndrome (PCOS). More recently, bariatric surgery, such as Roux-en-Y gastric bypass (RYGBP), has also been associated with improvement in IR and amelioration of PCOS and may, therefore, be beneficial in NCAH. We report a case of a 39-year-old, deaf-mute, obese woman with NCAH due to 11-hydroxylase deficiency who underwent RYGBP followed by improvement of NCAH manifestations. She was initially treated with metformin and pioglitazone, which lowered serum 11-deoxycortisol from 198 ng/dl (<51) to 26 ng/dl. Five weeks after undergoing RYGBP her body mass index fell from 44.18 kg/m(2) to 39.54 kg/m(2) and, despite not taking metformin or pioglitazone, serum 11-deoxycortisol remained normal at <40 ng/dl. Concurrently and subsequently, her NCAH symptoms, for example, alopecia, hirsutism and irregular menses normalised as well. We conclude that RYGBP, like other interventions that reduce IR, may be another way of treating non-classic 11-hydroxylase deficiency in selected patients.

Ashwagandha root in the treatment of non-classical adrenal hyperplasia.

Congenital adrenal hyperplasia (CAH) is a well-characterised family of disorders of the adrenal cortices, resulting in varying degrees of cortisol, aldosterone and androgen deficiency or androgen excess, depending on the enzyme(s) affected and the degree of quantitative or functional enzyme deficit. Withania somnifera (WS), commonly known as Ashwagandha, is a medicinal plant that has been employed for centuries in ayurvedic medicine. Preclinical studies have shown that WS increases circulating cortisol levels and improves insulin sensitivity. We report the case of a 57-year-old woman with non-classical adrenal hyperplasia due to both 3-ß-ol dehydrogenase deficiency and aldosterone synthase deficiency who was self-treated with WS for 6 months. After 6 months of treatment her serum 18-OH-hydroxycorticoserone, 17-OH-pregnenolone, corticosterone and 11-deoxycortisol decreased by 31%, 66%, 69% and 55%, respectively. The biochemical improvement was accompanied by a noticeable reduction in scalp hair loss.

Mapping protein-protein interactions by localized oxidation: consequences of the reach of hydroxyl radical.

Hydroxyl radicals generated from a variety of methods, including not only synchrotron radiation but also Fenton reactions involving chelated iron, have become an accepted macromolecular footprinting tool. Hydroxyl radicals react with proteins via multiple mechanisms that lead to both polypeptide backbone cleavage events and side chain modifications (e.g., hydroxylation and carbonyl formation). The use of site-specifically tethered iron chelates can reveal protein-protein interactions, but the interpretation of such experiments will be strengthened by improving our understanding of how hydroxyl radicals produced at a point on a protein react with other protein sites. We have developed methods for monitoring carbonyl formation on proteins as a function of distance from a hydroxyl generator, iron-(S)-1-[p-(bromoacetamido)benzyl]EDTA (FeBABE), conjugated to an engineered cysteine residue. After activation of the chelated iron with ascorbate and peroxide produces new protein carbonyl groups, their positions can be identified using element-coded affinity tagging (ECAT), with carbonyl-specific tags {e.g., rare earth chelates of (S)-2-[4-(2-aminooxy)acetamidobenzyl]-1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid (AOD)} that allow for affinity purification, identification, and relative quantitation of oxidation sites using mass spectrometry. Intraprotein oxidation of single-cysteine mutants of Escherichia coli sigma(70) by tethered FeBABE was used to calibrate the reach of hydroxyl radical by comparison to the crystal structure; the application to protein-protein interactions was demonstrated using the same sigma(70) FeBABE conjugates in complexes with the RNA polymerase core enzyme. The results provide fundamental information for interpreting protein footprinting experiments in other systems.