Functional Role of the Polymorphic 647 T/C Variant of ENT1 (SLC29A1) and Its Association with Alcohol Withdrawal Seizures

Adenosine is involved in several neurological and behavioral disorders including alcoholism. In cultured cell and animal studies, type 1 equilibrative nucleoside transporter (ENT1, slc29a1), which regulates adenosine levels, is known to regulate ethanol sensitivity and preference. Interestingly, in humans, the ENT1 (SLC29A1) gene contains a non-synonymous single nucleotide polymorphism (647 T/C; rs45573936) that might be involved in the functional change of ENT1. Our functional analysis showed that prolonged ethanol exposure increased adenosine uptake activity of mutant cells (ENT1-216Thr) compared to wild-type (ENT1-216Ile) transfected cells, which might result in reduced extracellular adenosine levels. We found that mice lacking ENT1 displayed increased propensity to ethanol withdrawal seizures compared to wild-type littermates. We further investigated a possible association of the 647C variant with alcoholism and the history of alcohol withdrawal seizures in subjects of European ancestry recruited from two independent sites. Analyses of the combined data set showed an association of the 647C variant and alcohol dependence with withdrawal seizures at the nominally significant level. Together with the functional data, our findings suggest a potential contribution of a genetic variant of ENT1 to the development of alcoholism with increased risk of alcohol withdrawal-induced seizures in humans

Characterization of a culture method to recover helicobacter pylori from the feces of infected patients.

BACKGROUND: Helicobacter pylori is difficult to culture from stool. Multiple efforts from multiple laboratories have been unsuccessful, and the optimal conditions to recover H. pylori from stool are still not known. Recovery of H. pylori from feces of infected individuals is important for the performance of molecular epidemiological investigations, especially in children, where their symptoms do not warrant endoscopy to recover the organism. METHODS: Fresh fecal specimens (noncathartic) were obtained from 19 known H. pylori-infected patients and were processed to recover the organism. Fresh fecal specimens (noncathartic) were also obtained from three known H. pylori-negative individuals (controls) to determine whether H. pylori could be isolated from stools seeded with known concentrations of the organism. Treatment of the fecal suspensions with cholestyramine, a basic anion exchange resin that binds bile acids, was used in an attempt to enhance recovery of H. pylori by sequestering bile acids that are inhibitory to H. pylori growth. H. pylori was identified based on colony morphology, cell morphology, Gram's stain, biochemical reactions, and polymerase chain reaction for two H. pylori genes. RESULTS: Among 19 patients, H. pylori was cultured at least once from 3 and three times from 2 (5 of 19). Feces that were seeded with H. pylori and obtained from three H. pylori-negative volunteer controls yielded positive recovery in all instances

Effect of H. pylori infection and CagA status on leukocyte counts and liver function tests: extra-gastric manifestation of H. pylori infection

It has been suggested that H. pylori infection is associated with abnormalities in total leukocyte count as well as the number of basophils and lymphocytes. In addition, CagA seropositivity has been associated with an increase in serum transaminase (SGOT) values. The aim of this study was to confirm the findings of previous subgroup analyses in patients before and after treatment for H. pylori infection and to ascertain whether the abnormalities reversed following successful treatment. METHODS: Blood counts and serum transaminase levels were obtained prior to and following treatment of H. pylori infection of H. pylori-infected duodenal ulcer patients. CagA status was assessed by Western blot of the H. pylori isolates obtained from the patients. RESULTS: Ninety-four ulcer patients were studied, including 77 with CagA-positive H. pylori isolates (82%) and 17 with CagA-negative H. pylori isolates. All study parameters remained within normal limits both before and after therapy. There were no significant changes in any study parameter in those who failed therapy. Successful therapy resulted in a significant fall in total white cell count (7413 +/- 520 cmm to 6738 +/- 410 cmm, for pretreatment vs. cured, respectively, p = 0.04) and was almost entirely accounted for by a reduction in the number of circulating polymorphonuclear leukocytes (4595 +/- 370 cmm to 3855 +/- 270 cmm for pretreatment vs. cured, respectively, p = 0.015). The pretreatment SGOT and basophil count were significantly higher in those with CagA-positive H. pylori (SGOT = 23 +/- 1 vs. 18.5 +/- 1 U). Successful or failed therapy with follow-up for 3 months post therapy did not result in a significant change of SGOT levels. CONCLUSIONS: We confirmed an increase in total leukocyte count and number of polymorphonuclear leukocytes in those with H. pylori infection. We also confirmed higher SGOT levels with CagA-positive H. pylori infection, but the failure to resolve within 3 months of cure of the infection makes it unlikely to be a direct result of the H. pylori infection

Helicobacter pylori in sheep milk.

Helicobacter pylori was recovered from sheep milk, suggesting a role for animals in transmission. H pylori may be a commensal in the sheep, which may be H pylori’s ancestral host

Demonstration of unexpected antibiotic resistance of genotypically identical Helicobacter pylori isolates.

With use of multiple- and single-colony expansion procedures, the results of susceptibility testing of Helicobacter pylori isolates from patients with duodenal ulcer were assessed by Etest. The H. pylori genotype was assessed by repetitive extragenic palindrome-based polymerase chain reaction (REP-PCR). There was a high degree of genotypic heterogeneity between different patients, but a single REP-PCR pattern was found for 92% of patients. In contrast, a high degree of phenotypic heterogeneity was shown among the isolated colonies. Antibiogram susceptibility patterns differed only with respect to metronidazole but not with respect to clarithromycin or amoxicillin. The 42% rate of resistance to metronidazole determined with use of the conventional multiple-strains expansion method was increased to 92% when the single-colony expansion method was used. Similarly, dual clarithromycin/metronidazole resistance was increased from 8% to 42% with single-colony expansion. Despite evidence of a single genotype in most patients, single-colony expansion shows that routine susceptibility testing may greatly underestimate the frequency of metronidazole resistance