Woodinine and its Stereomers - Absolute Configuration

The synthesis of all the four stereomers of the alkaloid woodinine ( 12a )¹⁾ is described and the stereochemical conclusions of Païs³⁾ and Still⁶⁾ are discussed. The absol. configurations of woodinine ( 12a ) and its diastereomer 8b are unequivocally deduced from the pertinent piperazinediones 16 and 17 .     

Oral Nitrate Reductase Activity and Erosive Gastro-esophageal Reflux Disease: A Nitrate Hypothesis for GERD Pathogenesis

Background  

Despite the rich literature on GERD, its cause and reason for increased prevalence remain obscure. Currently accepted mechanisms leave many questions unanswered. Nitrite chemistry at the GEJ is well described for carcinogenesis. Recent epidemiological and animal data have linked nitrates to GERD. “Nitrate reductase” of oral bacteria converts nitrates to nitrites. We hypothesized that nitrate reductase activity is higher in patients with erosive GERD, delivering more nitrite at the gastroesophageal-junction for a given nitrate intake.     

Low Helicobacter pylori eradication rates with 4- and 7-day regimens in an Iranian population

BACKGROUND: In Iran, there is insufficient information on the efficacy of Helicobacter pylori eradication regimens shorter than 10 days. This study aims at assessing the efficacy of 4- and 7-day H. pylori eradication regimens in a high-incidence area of gastric cancer in Iran. METHODS: Subjects with an endoscopic diagnosis of gastritis, positive urease test, and a histological diagnosis of chronic gastritis were enrolled. Patients were randomly assigned to one of three groups: AOC7 (1000 mg amoxicillin, 20 mg omeprazole, and 500 mg clarithromycin twice daily for 7 days), FOT4 (200 mg furazolidone, 20 mg omeprazole, and 500 mg tetracycline twice daily for 4 days) and FOT7 (the same treatment as the FOT4 group but for 7 days). Sensitivity to these antibiotics was determined in all isolates recovered from culture. The efficacy of eradication was assessed 8 weeks after the end-of-treatment by the 14C-urea breath test. RESULTS: One hundred and twenty-eight patients were enrolled in the study. Culture was positive for 84 patients and none of these were resistant to amoxicillin, tetracycline or furazolidone, 1.2% were resistant to clarithromycin and 32.1% to metronidazole. Forty-five, 41 and 42 patients were randomly allocated to the AOC7, FOT4, and FOT7 groups, respectively. The intention-to-treat eradication rates were 35.5, 17.1, and 23.8% for the AOC7, FOT4, and FOT7 groups, respectively. CONCLUSION: Treatment regimens of 4 or 7 days are unacceptable for H. pylori infection in Iran, even in the presence of a favorable sensitivity profile.     

Prevalence and pattern of antimicrobial resistance of Shigella species among patients with acute diarrhoea in Karaj,Tehran, Iran

The study was carried out to determine the prevalence and pattern of antimicrobial resistance of Shigella species among patients with acute diarrhoea in Karaj, Tehran, Iran. The study included all acute diarrhoea patients who visited the hospitals and treatment centres of Karaj during November 2001-October 2002. Of 734 stool samples collected from patients with acute diarrhoea and analyzed for Shigella spp., 123 (16.8%) yielded Shigella spp. (7.5% Shigella flexneri, 5.2% S. sonnei, 2.6% S. dysenteriae, and 1.5% S. boydii). Of the Shigella isolates, 90.8% were resistant to one or more antimicrobial agent(s), and 87.8% were multidrug resistant. The most common resistance was to tetracycline (73.5%), trimethoprim-sulphamethoxazole (70.4%), and amoxicillin-clavulanic acid (50.0%). Resistance to cefixime, ciprofloxacin, ceftriaxone, and nalidixic acid was observed in 6.1%, 3.1%, 2.0%, and 1.0% of the isolates respectively. These findings suggest that Shigella spp. may be an important aetiological agent of diarrhoea with a high rate of drug resistance in this region, which requires further study.     

Two volatiles from the venom gland of the Samsum ant, Pachycondyla sennaarensis

Allergy and anaphylactic reactions after the stings of the Samsum ant Pachycondyla sennaarensis (Mayr, 1862) (Hymenoptera: Formicidae) have been reported from several countries along the Persian Gulf coast, but no analysis has been yet carried out on the ant's venom gland secretions. This study is focused on the identification of volatiles from the venom gland of Pachycondyla sennaarensis using gas chromatography-mass spectrometry, which showed the presence of The main volatile components of the venom gland were phenol-2,4-bis(1,1 dimethylethyl) and trimethyl pyrazine. This is the first record of the occurrence of phenol-2,4-bis(1,1 dimethylethyl) in insects. The venom gland secretions of Pachycondyla species are known contain a variety of volatiles, making the members of this genus distinctive among the ponerine ants.     

Synthese von Carbazolderivaten, 2. Mitt.: 2-Substituierte Indole als Zwischenprodukte von Pyrrolino[3,4-c]carbazolen

Synthesis of Carbazole Derivatives, II: C-2-substituted Indoles as Intermediates of Pyrrolino[3,4-c]carbazoles Starting from the indole derivatives 4, 7 and 15 Grignard reaction, nucleophilic substitution at the pertinent dithian, and Wittig reaction afford preparatively useful side chains. By intramolecular Michael reaction the pertinent compounds lead to the pyrrolidino- and pyrrolino[3,4-c]carbazoles 32 and 33 , respectively.     

Antimykobakteriell wirksame Indolderivate

Indole Derivatives with Antimycobacterial Activity 1,3-Dinitro-2-(indol-3′-yl)-propanes 3 are synthesized by Michael reaction of nitromethane with the indolylnitroethenes 2 . - Reaction of the aldehydes 4 and 10 with the benzylamines 12 as well as the reaction of the indolylalkylamines 6a and 9a with the benzaldehydes 11 lead to Schiff bases which are reduced to N-benzyl-(indol-3-ylmethyl)-amines 13 and N-benzyl-(indol-3-ylethyl)-amines 14 , respectively; tert amines 16 are synthesized via the formamides 15 , amines 18 are prepared according to Mannich. -Inhibitory effects on Mycobacterium tuberculosis H 37 Ra are investigated, a structure-activity relationship is discussed.     

Freestyle Valve Experience: Technical Considerations and Mid-term Results

BACKGROUND: Many studies have demonstrated the superior hemodynamics of stentless porcine aortic valves compared to stented valves. This article describes the operative techniques and reviews our 5-year experience with the Medtronic Freestyle stentless valve. METHODS: Between January 1993 and November 1997, 95 patients underwent implantation of the Medtronic Freestyle valve at a mean age of 76 years. All patients were seen at 6 months, 1 year, and annually thereafter for clinical assessment and Doppler echocardiography. RESULTS: There were three operative and ten late deaths (two cardiac and eight noncardiac). Three strokes and four transient ischemic attacks occurred in the follow-up period. Four patients had bacteremia that was treated successfully with antibiotics. No patient required reoperation for valve-related problems. Serial echocardiograms revealed a decrease in mean systolic gradients across the valve during the first year and an increase in effective orifice areas. Ninety-one percent of patients had no, or trace, aortic insufficiency at the time of discharge and this has not increased over time. CONCLUSION: The Medtronic Freestyle valve has excellent hemodynamics and good clinical results. In our experience, no patient has required reoperation in a 5-year follow-up.