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Limited data exist on the spatial distribution of the colonic bacteria in humans. We collected the colonic biopsies from five segments of 27 polyp-free adults and collected feces from 13 of them. We sequenced the V4 region of the bacterial 16S rRNA gene using the MiSeq platform. The sequencing data were assigned to the amplicon sequence variant (ASV) using SILVA. Biodiversity and the relative abundance of the ASV were compared across the colonic segments and between the rectal and fecal samples. Bacterial functional capacity was assessed using Tax4fun. Each individual had a unique bacterial community composition (Weighted Bray–Curtis P value = 0.001). There were no significant differences in richness, evenness, community composition, and the taxonomic structure across the colon segments in all the samples. Firmicutes (47%), Bacteroidetes (39%), and Proteobacteria (6%) were the major phyla in all segments, followed by Verrucomicrobia, Fusobacteria, Desulfobacterota, and Actinobacteria. There were 15 genera with relative abundance > 1%, including Bacteroides, Faecalibacterium, Escherichia/Shigella, Sutterella, Akkermansia, Parabacteroides, Prevotella, Lachnoclostridium, Alistipes, Fusobacterium, Erysipelatoclostridium, and four Lachnospiraceae family members. Intra-individually, the community compositional dissimilarity was the greatest between the cecum and the rectum. There were significant differences in biodiversity and the taxonomic structure between the rectal and fecal bacteria. The bacterial community composition and structure were homogeneous across the large intestine in adults. The inter-individual variability of the bacteria was greater than inter-segment variability. The rectal and fecal bacteria differed in the community composition and structure.

BACKGROUND: NMDA receptors regulate synaptic plasticity and modulate a wide variety of behaviors. Mammalian NMDA receptors are inhibited by ethanol even at low concentrations. In mice, the F639A mutation in transmembrane domain 3 of the NR1 subunit reduces ethanol sensitivity of the receptor and in some paradigms, reduces behavioral ethanol sensitivity and increases ethanol consumption. We tested the fly equivalent of the F639A and K544Q mutations for effects on ethanol sensitivity. Drosophila shows a high degree of behavioral and mechanistic conservation in its responses to ethanol. METHODS: Homologous recombination and CRISPR/Cas9 genome editing were used to generate amino acid changes in the Drosophila NMDAR1 gene, yielding F654A and K558Q alleles. Animals were tested for the degree of ethanol sensitivity, the ability to acquire tolerance to ethanol, ethanol drinking preference, circadian rhythmicity, learning, and locomotor defects. RESULTS: We observed that mutating the NMDAR1 channel also reduces ethanol sensitivity in adult flies. However, in flies, it was the K558Q mutation (orthologous to K544Q in mice) that reduces ethanol sensitivity in a recovery-from-sedation assay. The effects of the F654A mutation (orthologous to F639A in mice) were substantially different in flies than in mammals. In flies, F654A mutation produces phenotypes opposite those in mammals. In flies, the mutant allele is homozygous viable, does not seem to affect health, and increases ethanol sensitivity. Both mutations increased feeding but did not alter the animal’s preference for 5% ethanol food. F654A depressed circadian rhythmicity and the capacity of males to court, but it did not depress the capacity for associative learning. K554Q, on the other hand, has little effect on circadian rhythmicity, only slightly suppresses male courtship, and is a strong learning mutant. CONCLUSIONS: Mutations in transmembrane domain 3 and in the extracellular vestibule calcium binding site of the NR1 NMDA subunit affect ethanol sensitivity in Drosophila.

Past research has established that Drosophila gut inflammation via the dual oxidase (DUOX) regulatory pathway is induced by exposure to bacterial-derived uracil, which can be secreted by allochthonous and autochthonous bacteria in the midgut. However, the effects of the inflammatory response and resulting gut dysbiosis on the courtship behavior of the Drosophila host have yet to be determined. This work studies the changes in Drosophila courtship behavior resulting from diet-based exposure to uracil, a ligand for DUOX-dependent reactive oxygen species (ROS) generation in the epithelia of the midgut. The effects of a high-uracil diet on courtship behavior were determined by comparing courtship index (CI) values of flies treated with 20 nM of uracil for 16-hr (short-term) or 10-d (long-term) exposure to age-matched control flies. Although short-term uracil treatment caused no change in courtship behavior, long-term uracil treatment resulted in a significant decrease in CI. This result suggests that the underlying association for the behavioral change may be influenced by gut inflammation initiated by long-term exposure to uracil. By measuring the effects of an innate immune response such as exposure to a ligand for DUOX-dependent ROS generation on the courtship index of Drosophila, the current understanding of the relationship between gut inflammation and behavioral changes in animals can be expanded. Given that prior research has also established that the DUOX-dependent response can be found in animals ranging from Drosophila to humans, the behavioral changes observed from induction of the pathway have the potential to expand this connection in the future.

The ventral tegmental area (VTA) plays an important role in the reward and motivational processes that facilitate the development of drug addiction. Presynaptic &alpha, 1-AR activation modulates glutamate and Gamma-aminobutyric acid (GABA) release. This work elucidates the role of VTA presynaptic &alpha, 1-ARs and their modulation on glutamatergic and GABAergic neurotransmission during cocaine sensitization. Excitatory and inhibitory currents (EPSCs and IPSCs) measured by a whole cell voltage clamp show that &alpha, 1-ARs activation increases EPSCs amplitude after 1 day of cocaine treatment but not after 5 days of cocaine injections. The absence of a pharmacological response to an &alpha, 1-ARs agonist highlights the desensitization of the receptor after repeated cocaine administration. The desensitization of &alpha, 1-ARs persists after a 7-day withdrawal period. In contrast, the modulation of &alpha, 1-ARs on GABA neurotransmission, shown by decreases in IPSCs&rsquo, amplitude, is not affected by acute or chronic cocaine injections. Taken together, these data suggest that &alpha, 1-ARs may enhance DA neuronal excitability after repeated cocaine administration through the reduction of GABA inhibition onto VTA dopamine (DA) neurons even in the absence of &alpha, 1-ARs&rsquo, function on glutamate release and protein kinase C (PKC) activation. &alpha, 1-AR modulatory changes in cocaine sensitization increase our knowledge of the role of the noradrenergic system in cocaine addiction and may provide possible avenues for therapeutics.

Chronic cocaine exposure produces enduring neuroadaptations in the brain's reward system. Persistence of early cocaine-evoked neuroadaptations in the ventral tegmental area (VTA) is necessary for later synaptic alterations in the nucleus accumbens (NAc), suggesting a temporal sequence of neuroplastic changes between these two areas. However, the molecular nature of the signal that mediates this sequential event is unknown. Here we used the behavioral sensitization model and the aPKC inhibitor of late-phase LTP maintenance, ZIP, to investigate if a persistent increase in AMPA/NMDA ratio plays a role in the molecular mechanism that allows VTA neuroadaptations to induce changes in the NAc. Results showed that intra-VTA ZIP microinfusion successfully blocked cocaine-evoked synaptic enhancement in the VTA and the expected AMPA/NMDA ratio decrease in the NAc following cocaine sensitization. ZIP microinfusions also blocked the expected AMPA/NMDA ratio increase in the NAc following cocaine withdrawal. These results suggest that a persistent increase in AMPA/NMDA ratio, mediated by aPKCs, could be the molecular signal that enables the VTA to elicit synaptic alterations in the NAc following cocaine administration.

Chronic cocaine exposure produces enduring neuroadaptations in the brain’s reward system. Persistence of early cocaine evoked neuroadaptations in the ventral tegmental area (VTA) are necessary for later synaptic alterations in the nucleus accumbens (NAc), suggesting a temporal sequence of neuroplastic changes between these two areas. However, the molecular nature of the signal that mediates this sequential event is unknown. Here we used the behavioral sensitization model and the aPKC inhibitor of late-phase LTP maintenance, ZIP, to investigate if a persistent increase in AMPA/NMDA ratio plays a role in the molecular mechanism that allows VTA neuroadaptations to induce changes in the NAc. Results showed that intra-VTA ZIP microinfusion successfully blocked cocaine evoked synaptic enhancement in the VTA and the expected AMPA/NMDA ratio decrease in the NAc following cocaine sensitization. ZIP microinfusions also blocked the expected AMPA/NMDA ratio increase in the NAc following cocaine withdrawal. These results suggest that a persistent increase in AMPA/NMDA ratio, mediated by aPKC’s, could be the molecular signal that enables the VTA to elicit synaptic alterations in the NAc following cocaine administration.

One carbon (1C) metabolism nutrients influence epigenetic regulation and they are supplied by diet and synthesized by gut microbiota. We examined the association between dietary consumption of methyl donors (methionine, betaine and choline) and B vitamins (folate, B2, B6, and B12) and the community composition and structure of the colonic mucosa-associated gut microbiota determined by 16S rRNA gene sequencing in 97 colonic biopsies of 35 men. We used the food frequency questionnaire to assess daily consumption of nutrients, and the UPARSE and SILVA databases for operational taxonomic unit classification. The difference in bacterial diversity and taxonomic relative abundance were compared between low versus high consumption of these nutrients. False discover rate (FDR) adjusted p value &lt, 0.05 indicated statistical significance. The bacterial richness and composition differed significantly by the consumption of folate and B vitamins (p &lt, 0.001). Compared with higher consumption, a lower consumption of these nutrients was associated with a lower abundance of Akkermansia (folate), Roseburia (vitamin B2), and Faecalibacterium (vitamins B2, B6, and B12) but a higher abundance of Erysipelatoclostridium (vitamin B2) (FDR p values &lt, 0.05). The community composition and structure of the colonic bacteria differed significantly by dietary consumption of folate and B vitamins.

Recent studies using histology alone in select patients have suggested that Helicobacter pylori-negative gastritis may be common. The objective of this study was to investigate the prevalence of H. pylori among individuals with histologic gastritis.Subjects between 40 and 80 years underwent elective esophagogastroduodenoscopy at a VA Medical Center. Gastric biopsies were mapped from seven prespecified sites (two antrum, four corpus, and one cardia) and graded by two gastrointestinal pathologists, using the Updated Sydney System. H. pylori-negative required four criteria: negative triple staining at all seven gastric sites, negative H. pylori culture, negative IgG H. pylori serology, and no previous treatment for H. pylori. Data regarding tobacco smoking, alcohol drinking, nonsteroidal anti-inflammatory drug, and proton pump inhibitor (PPI) use were obtained by questionnaire.Of the 491 individuals enrolled, 40.7% (200) had gastritis of at least grade 2 in at least one biopsy site or grade 1 in at least two sites. Forty-one (20.5%) had H. pylori-negative gastritis; most (30 or 73.2%) had chronic gastritis, five (12.2%) had active gastritis, and six (14.6%) had both. H. pylori-negative gastritis was approximately equally distributed in the antrum, corpus, and both antrum and corpus. Past and current PPI use was more frequent in H. pylori-negative vs. H. pylori-positive gastritis (68.2% and 53.8%; P=0.06).We used multiple methods to define non-H. pylori gastritis and found it in 21% of patients with histologic gastritis. While PPI use is a potential risk factor, the cause or implications of this entity are not known.

Background: Diet is a modifiable risk factor for multiple cancers. It is also known to modulate gut microbial composition and metabolic activity, and plays an important role in maintaining gut homeostasis. However, our understanding of dietary quality and mucosa-associated microbiota in the large intestine in humans is limited. We examined the association between diet quality and gut microbiota in adults underwent routine colonoscopy in a cross-sectional study. Methods: We enrolled 21 men (50-75 years old, 71% White) who were found to have grossly normal colons at colonoscopy completed between July 2013 and April 2016. We obtained 98 colonic mucosa biopsies, with microbial DNA extracted from snap frozen biopsy. The 16S rRNA V4 region was amplified and sequenced on the Illumina MiSeq platform. The UPARSE and SILVA were used for operational taxonomic unit (OTU) classification. A self-administered BLOCK Food Frequency Questionnaire was used to assess dietary intake in the past year. Dietary quality was defined using the Healthy Eating Index (HEI)-2005, and further categorized as low or high using the median of total HEI or 12 individual component scores. We compared alpha-diversity (OTU and Shannon index), beta-diversity (Weighted UniFrac principal coordinates analysis), and relative abundance of bacterial phylum and genus by total HEI and all 12 individual HEI components using Mann-Whitney test. Reported P values were adjusted for multiple testing using false discovery rate. Results: The most abundant bacterial phyla observed were Firmicutes, Bacteroidetes, Proteobacteria, Verrucomicrobia, and Fusobacteria. High-quality diet (total HEI score ≥ 63) was not associated with higher richness and evenness of gut microbiome (P = 0.12), but was significantly associated with bacterial composition (P = 0.046). Compared to men who had low-quality diet (total HEI score < 63), those with high-quality diet had a higher abundance of Proteobacteria (12.2% vs. 8.1%, P = 0.006), and lower abundance of Fusobacteria (0.13% vs. 3.37%, P = 0.004). At the genus level, those with high-quality diet had significantly lower abundance of Fusobacterium than those with low-quality diet (0.11% vs. 3.77%, P = 0.004). At the HEI component level, individuals with a higher consumption of solid fruits and milk had higher richness and evenness of gut microbiome (P < 0.05) as well as higher abundance of phylum Verrucomicrobia (P < 0.05) and genus Akkermansia (P < 0.001). Consuming more solid and saturated fat, alcohol, and added sugar were associated with a higher abundance of phylum Fusobacteria (P < 0.0001) and genus Fusobacterium (P = 0.0001). Conclusions: The colonic microbiome of men consuming a low-quality diet exhibited increased levels of Fusobacteria, which has been associated with colorectal cancer risk. If replicated in prospective research, our findings suggest low quality diet may contribute to colorectal cancer by modulating gut microbiome. Citation Format: Yanhong Liu, Nadim J. Ajami, Diane Hutchinson, David Graham, Sarah Plew, Ashley Johnson, Preksha Shah, Liang Chen, Kathryn Royse, Donna L. White, Jennifer Kramer, Matthew C. Wong, Rhonda Cole, Clark Hair, Jason Hou, Nisreen Husain, Maria Jarbrink-Sehgal, Fasiha Kanwal, Gyanprakash Ketwaroo, Rajesh Shah, Maria Velez, Melissa L. Bondy, Hashem B. El-Serag, Joseph F. Petrosino, Li Jiao. Healthy eating index 2005 and the mucosa associated gut microbiome in healthy individuals [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3265.

Inadequate follow-up of abnormal fecal occult blood test (FOBT) results occurs in several types of practice settings. Our institution implemented multifaceted quality improvement (QI) activities in 2004-2005 to improve follow-up of FOBT-positive results. Activities addressed precolonoscopy referral processes and system-level factors such as electronic communication, provider education, and feedback. We evaluated their effects on timeliness and appropriateness of positive-FOBT follow-up and identified factors that affect colonoscopy performance.Retrospective electronic medical record review was used to determine outcomes before and after QI activities in a multispecialty ambulatory clinic of a tertiary care Veterans Affairs facility and its affiliated satellite clinics. From 1869 FOBT-positive cases, 800 were randomly selected from time periods before and after QI activities. Two reviewers used a pretested standardized data collection form to determine whether colonoscopy was appropriate or indicated based on predetermined criteria and if so, the timeliness of colonoscopy referral and performance before and after QI activities.In cases where a colonoscopy was indicated, the proportion of patients who received a timely colonoscopy referral and performance were significantly higher post-implementation (60.5% vs. 31.7%, P0.0001 and 11.4% vs. 3.4%, P=0.0005). A significant decrease also resulted in median times to referral and performance (6 vs. 19 days, P0.0001 and 96.5 vs. 190 days, P0.0001) and in the proportion of positive-FOBT test results that had received no follow-up by the time of chart review (24.3% vs. 35.9%, P=0.0045). Significant predictors of absence of the performance of an indicated colonoscopy included performance of a non-colonoscopy procedure such as barium enema or flexible sigmoidoscopy (OR=16.9; 95% CI, 1.9-145.1), patient non-adherence (OR=33.9; 95% CI, 17.3-66.6), not providing an appropriate provisional diagnosis on the consultation (OR=17.9; 95% CI, 11.3-28.1), and gastroenterology service not rescheduling colonoscopies after an initial cancellation (OR=11.0; 95% CI, 5.1-23.7).Multifaceted QI activities improved rates of timely colonoscopy referral and performance in an electronic medical record system. However, colonoscopy was not indicated in over one third of patients with positive FOBTs, raising concerns about current screening practices and the appropriate denominator used for performance measurement standards related to colon cancer screening.

Enteral nutrition (EN) provisions are typically calculated based on a 24-hour infusion period. However, feedings are often interrupted for daily activities, procedures, or gastrointestinal intolerance. The study's objective was to determine the delivered EN quantities provided to stable hospitalized patients, using cellular time and measured volumes to verify our EN calculation adjustment.A supply of consecutively numbered ready-to-hang (RTH) EN product was delivered to the bedside of 26 inpatients with established EN tolerance at goal rates on various types of nursing units. The dietitian weighed the volume remaining in the infusing product and recorded the measurement time. On the following days, the dietitian continued to weigh the infusing RTH product and the empty RTH bottles saved by nursing. The primary outcome was the difference between the prescribed and delivered EN provisions, which was calculated with a paired t test.Patients received significantly more calories in the delivered enteral feeding (mean [SD], 1678 [385] kcal) than prescribed calories in the EN order (1489 [246 kcal]; t = 3.736, P = .001), adjusting for observed time. No significant differences were found between nursing units, product, and rate.EN delivered may actually exceed ordered amounts by 5%–21% (mean, 12%) with feeding pump inaccuracy as the primary contributing factor. This differs from what others have found. Our findings support using a volume-based ordering system vs a rate-based ordering system for more accurate EN delivery.

Chronic alcoholics have a high prevalence of hepatitis C virus (HCV) infection. The present study was carried out to examine the association between HCV infection and alcohol abuse, and the influence of these factors on the severity of liver disease. Patients with history of heavy alcohol abuse (> or = 80 g of ethanol per day for > or = 5 years) were analyzed with respect to the amount of alcohol use, clinical evidence of liver disease, and laboratory tests. One hundred ninety-nine patients, 137 HCV positive and 62 HCV negative were included in the study. HCV-infected subjects had liver disease for a longer duration (P < 0.0001) and had higher incidence of symptoms of hepatic decompensation in the past compared to uninfected alcoholics. Several differences were noted between the two groups at the time of presentation to the hospital. Alcoholics with HCV infection had lower daily alcohol consumption (P < 0.001), were abstinent for a longer duration (P < 0.02) and had lower lifetime use of ethanol (P < 0.005) compared to HCV-negative subjects. Assessment of liver tests showed greater derangement in uninfected alcoholics compared to HCV-positive subjects. The present study shows that HCV-infected chronic alcoholics have lower alcohol consumption and, perhaps as a consequence, have less severe liver disease compared to HCV-negative individuals. These findings suggest that in chronic alcoholics, despite the presence of HCV infection, the severity of liver damage is related to the amount of alcohol consumption.

Studied since the 1940s, refeeding syndrome still has no universal definition, thus making comparison of studies difficult. Negative outcomes (eg, metabolic abnormalities) may occur with the use of specialized nutrition, such as parenteral nutrition (PN). Less than half of medical institutions have a nutrition support team (NST) managing PN. Interdisciplinary team management of PN may reduce negative outcomes of PN. The objective of this study was to show the value of the NST by measuring differences in PN variables, especially electrolyte abnormalities (EAs), before and after NST initiation at a large medical center and to identify factors associated with EAs among adult subjects receiving PN.During this retrospective study, computerized medical charts (N = 735) from 2007-2010 were reviewed for electrolyte changes (particularly potassium, magnesium, and phosphorus) the first 3 days following PN initiation in hospitalized adults. Changes in EAs with other variables were compared before and after NST implementation. Equivalent samples sizes were collected to better evaluate the impact of the team.Following the implementation of the NST, fewer EAs were seen in PN patients (53%; χOur study complements existing research, finding that an NST was associated with a decreased occurrence of EAs and mortality in the hospitalized adult receiving PN.

Objective Abdominal obesity has been associated with increased risk of Barrett9s oesophagus (BE) but the underlying mechanism is unclear. We examined the association between visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) and the risk of BE. Design A case-control study among eligible patients scheduled for elective oesophagastroduodenoscopy (EGD) and in a sample of patients eligible for screening colonoscopy recruited at the primary care clinic. All cases with definitive BE and a random sample of controls without BE were invited to undergo standardised mid-abdomen non-contrast computerised axial tomography images, which were analysed by semiautomated image segmentation software. The effect of VAT and SAT surface areas and their ratio (VAT to SAT) on BE were analysed in logistic regression models. Results A total of 173 BE cases, 343 colonoscopy controls and 172 endoscopy controls underwent study EGD and CT scan. Participants with BE were more than twice as likely to be in the highest tertile of VAT to SAT ratio (OR: 2.42 (1.51 to 3.88) and adjusted OR 1.47 (0.88 to 2.45)) than colonoscopy controls, especially for those long (≥3 cm) segment BE (3.42 (1.67 to 7.01) and adjusted OR 1.93 (0.92 to 4.09)) and for white men (adjusted OR 2.12 (1.15 to 3.90)). Adjustment for gastroesophageal reflux disease (GERD) symptoms and proton pump inhibitors (PPI) use attenuated this association, but there was a significant increase in BE risk even in the absence of GERD or PPI use. Conclusions Large amount of visceral abdominal fat relative to subcutaneous fat is associated with a significant increase in the risk of BE. GERD may mediate some but not all of this association.

Patients chronically abusing ethanol are more susceptible to the hepatotoxic effects of paracetamol. This could be due to an increased activation of the drug to a toxic metabolite or to a decreased capacity to detoxify the toxic metabolite by conjugation with glutathione (GSH). To test these hypotheses paracetamol 2 g was administered to five chronic alcoholics without clinical evidence of alcoholic liver disease and five control subjects. The urinary excretion of cysteine- plus N-acetyl-cysteine-paracetamol, the two major products of detoxification of the reactive metabolite of paracetamol, was not significantly higher in chronic alcoholics arguing against a substantially increased metabolic activation of paracetamol. Chronic alcoholics had significantly lower plasma concentrations of GSH than healthy volunteers, however (4.35 (1.89) microM v 8.48 (2.68) microM, p less than 0.05) before the administration of paracetamol, and plasma GSH reached lower concentrations in the alcoholics after paracetamol (2.40 (1.36) v 6.26 (2.96) microM). In a group of patients with alcoholic hepatitis intrahepatic GSH was significantly lower than in patients with chronic persistent hepatitis and patients with non-alcoholic cirrhosis, suggesting that low plasma GSH in alcoholics reflects low hepatic concentrations of GSH. The data indicate that low GSH may be a risk factor for paracetamol hepatotoxicity in alcoholics because a lower dose of paracetamol will be necessary to deplete GSH below the critical threshold concentration where hepatocellular necrosis starts to occur.

Endoscopic injection sclerosis is a therapeutic alternative in the management of esophageal varices. Complications of sclerotherapy have been minor, including fever, bacteremia, and abnormal chest x-ray. We performed a prospective study to evaluate the frequency of postsclerosis bacteremia. Bacteremia was detected in 14 procedures (50%). There were no cases of bacteremia in a group of control patients with esophageal varices undergoing upper gastrointestinal endoscopy without sclerosis (p less than 0.05). Bacteremia was transient and unrelated to the presence of fever or other clinical complications. The organism most commonly cultured from blood, alpha-hemolytic streptococcus, probably represents a contaminant from the oropharynx, introduced into the bloodstream during sclerosis. We conclude that injection sclerotherapy of esophageal varices is associated with a higher incidence of bacteremia than routine upper endoscopy and that selected patients may require antibiotic prophylaxis when undergoing this procedure.