Validation of a new high-performance liquid chromatography assay for nizatidine

An expedient high-performance liquid chromatography (HPLC) assay for nizatidine measurement in human plasma was developed and validated. After deproteinization of 200 microL of plasma by filtration, nizatidine and 4-amino-antipyrine (internal standard) were separated (capacity ratio 3.0 and 6.63, respectively) on Nova-Pak C18 cartridge at room temperature (RT), and detected spectrophotometrically at 320 nm. The mobile phase, 0.02 mol/L disodium hydrogen phosphate, acetonitrile, methanol, and triethylamine (80:10:10:0.05 vol/vol), was delivered at 1.5 mL/min. Calibration curves were linear (r2 > or = 0.999) in the range 0.02 to 5 microg/mL, detection and quantification limits were 0.01 and 0.02 microg/mL, respectively, intra-run and inter-run coefficients of variation were < or = 3.5% and < or = 4.2%, respectively, and recovery was >90%. Nizatidine was stable for at least 4 hours at RT, 12 weeks at -20 degrees C, and 3 freeze-thaw cycles in plasma; 16 hours at RT and 48 hours at -20 degrees C in deproteinized plasma; and 6 hours at RT and 3 weeks at -20 degrees C in water.     

Severe Bleeding from Herpes Esophagitis

We describe a patient with the unusual complication of massive upper gastrointestinal bleeding secondary to herpetic esophagitis, whose bleeding persisted despite a vigorous antireflux regimen but who responded dramatically to intravenous acyclovir. The patient is reported to underscore the importance of considering herpetic infection of the esophagus as a cause of severe gastrointestinal bleeding so that appropriate therapy may be instituted.     

Antispasmodic effects of Rooibos tea (Aspalathus linearis) is mediated predominantly through K+ -channel activation

Rooibos tea has been widely used for abdominal spasm and diarrhoea. The aim of the present study was to explore the possible mechanism for its use in such ailments. Its aqueous extract (RT) at 0.3-10 mg/ml produced relaxation of spontaneous and low K(+) (25 mM)-induced contractions of rabbit jejunum, with weak effect on high K(+) (80 mM)-induced contractions. In the presence of glibenclamide, relaxation of low K(+)-induced contractions was prevented. Cromakalim inhibited contractions induced by low K(+), but not high K(+), while verapamil did not differentiate in its inhibitory effect on contractions produced by the two concentrations of K(+). RT also exhibited antidiarrhoeal and antisecretory activities in mice. The spasmolytic effect was concentrated in organic fractions. Its constituents, chrysoeriol, orientin and vitexin showed a similar pattern of spasmolytic effects to the extract, while rutin was more like verapamil. So Rooibos tea possesses a combination of dominant K(ATP) channel activation and weak Ca(++) antagonist mechanisms and hence justifies its use in hyperactive gastrointestinal disorders.     

Norditerpenoid alkaloids from Delphinium nordhagenii

Three new norditerpenoid alkaloids, nordhagenine A (1), nordhagenine B (2), and nordhagenine C (3), along with a known alkaloid, lycoctonine, were isolated from the aerial parts of Delphinium nordhagenii. The structures of the new compounds 1 and 2 were also deduced on the basis of single-crystal X-ray diffraction studies.     

In vivo anthelmintic activity of ginger against gastrointestinal nematodes of sheep

This paper describes the anthelmintic activity of Zingiber officinale Roscoe (family Zingiberaceae) rhizome, commonly known as ginger, to justify its traditional use in veterinary medicine. Crude powder (CP) and crude aqueous extract (CAE) of dried ginger (1-3 g/kg) were administered to sheep naturally infected with mixed species of gastrointestinal nematodes. Both CP and CAE exhibited a dose- and a time-dependent anthelmintic effect with respective maximum reduction of 25.6% and 66.6% in eggs per gram (EPG) of faeces on day 10 of post-treatment. Levamisole (7.5 mg/kg), a standard anthelmintic agent, exhibited 99.2% reduction in EPG. This study shows that ginger possesses in vivo anthelmintic activity in sheep thus justifying the age-old traditional use of this plant in helminth infestation.     

Arsenic exposure and age and sex-specific risk for skin lesions: a population-based case-referent study in Bangladesh

BACKGROUND: The objective of this population-based case-referent study in Matlab, Bangladesh, was to assess the susceptibility to arsenic-induced skin lesions by age and sex, in a population drinking water from As-contaminated tube wells. METHODS: Identification of As-related skin lesions was carried out in three steps: a) screening of the entire population > 4 years of age (n = 166,934) by trained field teams; b) diagnosis of suspected As-related cases by physicians; and c) confirmation by experts based on physicians' records and photographs. A total of 504 cases with skin lesions were confirmed. We randomly selected 2,201 referents from the Matlab health and demographic surveillance system; 1,955 were eligible, and 1,830 (94%) were available for participation in the study. Individual history of As exposure was based on information obtained during interviews and included all drinking-water sources used since 1970 and concentrations of As (assessed by atomic absorption spectrophotometry) in all the tube wells used. RESULTS: Cases had been exposed to As more than referents (average exposure since 1970: male cases, 200 microg/L; female cases, 211 microg/L; male referents, 143 microg/L; female referents, 155 microg/L). We found a dose-response relationship for both sexes (p < 0.001) and increased risk with increasing socioeconomic status. Males had a higher risk of obtaining skin lesions than females (odds ratio 10.9 vs. 5.78) in the highest average exposure quintile (p = 0.005). Start of As exposure (cumulative exposure) before 1 year of age was not associated with higher risk of obtaining skin lesions compared to start of As exposure later in life. CONCLUSIONS: The results demonstrate that males are more susceptible than females to develop skin lesions when exposed to As in water from tube wells.     

The efficacy of ferrous bisglycinate and electrolytic iron as fortificants in bread in iron-deficient school children

Food fortification is an important long-term strategy for addressing micronutrient deficiencies. Finding the ideal Fe fortification compound, however, remains a challenge. In the present study the effect of ferrous bisglycinate as fortificant in brown bread was compared with that of electrolytic Fe among Fe-deficient school children in a randomised controlled trial. Children (n 160), aged 6-11 years, with serum ferritin <20 microg/l, were randomly assigned to one of three treatment categories: (i) standard unfortified bread; (ii) bread with electrolytic Fe as fortificant; and (iii) bread with ferrous bisglycinate as fortificant. Each child received four slices of bread (120 g) on school days, which supplied an average of 3.66 mg elemental Fe per intervention day for 137 d (2.52 mg/d for 75 d and 5.04 mg/d for 62 d) over a period of 7.5 months. Hb, serum ferritin, serum Fe and transferrin saturation were measured at baseline and at the end of the intervention. Significant treatment effects were observed for Hb (P = 0.013), serum Fe (P = 0.041) and transferrin saturation (P = 0.042) in the ferrous bisglycinate group, but not in the electrolytic Fe group. There were no significant intervention effects for serum ferritin in either treatment group. Overall, ferrous bisglycinate as Fe fortificant in brown bread performed better than electrolytic Fe in a group of Fe-deficient school children over a period of 7.5 months.