The Novel Antihyperglycaemic Action of Hunteria Umbellata Seed Fractions Mediated Via Intestinal Glucose Uptake Inhibition

The present study evaluated the antihyperglycaemic effect and mechanism of action of fractions of the aqueous seed extract of Hunteria umbellata (K. Schum.) Hallier f. (HU) in normal and alloxan-induced hyperglycaemic rats. HU was partitioned in chloroform, acetyl acetate and butan-1-ol to give chloroform fraction (HU_c), ethyl acetate fraction (HU_e), butanol fraction (HU_b) and the “residue” (HU_m), respectively. 200 mg/kg of each of these fraction dissolved in 5% Tween 20 in distilled water was investigated for its acute oral hypoglycaemic effects in normal rats over 6 hours while its repeated dose antihyperglycaemic effect was evaluated in alloxan-induced hyperglycaemic rats over 5 days. In addition, 50 mg/kg of the crude alkaloid fraction (HU_Af) extracted from HU was evaluated for its possible antihyperglycaemic activity in alloxaninduced hyperglycaemic rats using oral glucose tolerance test (OGTT) over 6 hours. Using the solvent system, distilled water-butanol-ammonium hydroxide (2:15:1, v/v/v), HU_b was chromatographed and stained with Dragendorff''s reagent for confirmatory qualitative analysis for alkaloids. Results showed that oral pre-treatment with 200 mg/kg of HU_e, HU_b and HU_m resulted in a significant (p<0.05, p<0.001) time dependent hypoglycaemic effect, with the butan-1-ol fraction HU causing the most significant (p<0.001) hypoglycaemic effect. In the alloxan-induced hyperglycaemic rats, repeated oral treatment with 200 mg/kg of same HU fractions for 5 days resulted in significant (p<0.05) decreases in the fasting blood glucose concentrations with the most significant (p<0.01) antihyperglycaemic effect also recorded for HU_b. Similarly, oral pretreatment with 50 mg/kg of HU_Af significantly (p<0.05, p<0.01 and p<0.001) attenuated an increase in the post-absorptive glucose concentration at 1^st – 6^th h in the alloxan-induced hyperglycaemic OGTT model. In addition, alkaloid was present in most of the separated spots on the TLC plate. In conclusion, results of this study showed that HU contains a relative high amount of alkaloids which could have accounted for the antihyperglycaemic action of HU that was mediated via intestinal glucose uptake inhibition.     

Altered methionine metabolism in long living Ames dwarf mice

Ames dwarf mice (df/df) are deficient in growth hormone, prolactin, and thyroid-stimulating hormone and live significantly longer than their normal siblings. In the current study, we found that the hormone deficiencies affect methionine metabolism. We previously reported that the dwarf mice exhibit enzyme activities and levels that combat oxidative stress more efficiently than those of normal mice. Moreover, methionine or metabolites of methionine are involved in antioxidative processes. Thus, we performed an experiment that compared various parameters of methionine metabolism between 18-month old male dwarf (N=6) and wild type (N=5) mice. The specific activity of liver methionine adenosyltransferase (MAT) was significantly elevated (205%, p<0.0001) in the dwarf mice, as were cystathionine synthase (50%, p<0.01), cystathionase (83%, p<0.001), and glycine N-methyltransferase (GNMT, 91%, p<0.001) activities. Even though the activities of MAT and GNMT were elevated, the concentration of liver S-adenosylmethionine was decreased (24%, p<0.001) and S-adenosylhomocysteine increased (113%, p<0.001) in the dwarf mice. These data indicate that dwarf mice, compared to wild type mice, have a markedly different metabolism of methionine. Altered methionine metabolism may partially explain earlier reports indicating less oxidative damage to proteins in dwarf mice. Taken together, the data suggest that methionine metabolism may play a role in oxidative defense in the dwarf mouse and should be studied as a potential mechanism of extended lifespan.     

Pediatric pneumococcal bone and joint infections. The Pediatric Multicenter Pneumococcal Surveillance Study Group (PMPSSG)

OBJECTIVE: To describe the clinical and microbiological characteristics of infants and children with bone and joint infections caused by penicillin-susceptible and penicillin-nonsusceptible strains of Streptococcus pneumoniae. DESIGN: Multicenter, prospective patient accrual; retrospective chart review of identified patients. SETTING: Eight children's hospitals in the United States. PARTICIPANTS: Forty-two children with bone and/or joint infections prospectively enrolled in the United States Pediatric Multicenter Pneumococcal Surveillance Study from September 1, 1993 to August 31, 1996. OUTCOME MEASURES: Data were collected on multiple variables, including age, gender, race, days of symptoms before and during hospitalization, antibiotic and surgical therapy, laboratory and imaging studies. RESULTS: Of the 42 children enrolled (21 bone, 21 joint infections), 14 had isolates that were not susceptible to penicillin. Eight of 16 (50%) strains isolated from children who received antibiotics within 4 weeks before hospitalization were not susceptible to penicillin, compared with 4 of 15 (27%) strains isolated from children without previous antibiotic exposure. Clinical response to therapy was similar between children infected by penicillin-susceptible strains compared with those infected by penicillin-nonsusceptible strains, including duration of hospitalization (9.1 days vs 11.2 days), days of intravenous antibiotic therapy (25.3 days vs 24.6 days), days of fever (3.6 days vs 3.1 days), and sequelae (14% vs 7%). The most commonly prescribed single agents for parenteral therapy in definitive treatment were ceftriaxone (36%), penicillin (15%), and clindamycin (15%). Oral therapy followed parenteral therapy in 56% of children. The mean (+/- standard deviation) duration of total antibiotic therapy in children with osteomyelitis was 57.5 +/- 48.6 days (range, 23-196 days) and 29.2 +/- 11.8 days (range, 12-67 days) for arthritis. Late sequelae (long-term destructive changes of the bone or joint) were documented in 5 (12%) children, 4 with osteomyelitis, and 1 with arthritis. Sequelae occurred in 30% of children with long bone osteomyelitis associated with infection in the adjacent joint. The age of children with sequelae was younger than those without sequelae (6.4 months vs 18.6 months). CONCLUSIONS: The demographic characteristics and anatomic sites of infection in our patients were similar to previously published series collected from single institutions before the emergence of significant antibiotic resistance in S pneumoniae. Our analysis suggests that children infected by penicillin-nonsusceptible strains have a similar clinical response to therapy when compared with children infected by penicillin-susceptible strains.     

Necrotizing enterocolitis. Controlled study of 3 years' experience in a neonatal intensive care unit

During the 3 years 1972-74, 17 infants were treated for necrotizing enterocolitis (NEC) in the Neonatal Unit at University College Hospital. The incidence of the illness was 0.2% of live births in the hospital and 2.7% of those referred from elsewhere. The mean birthweight of the affected infants was 1832 g (range 878-3850 g) and mean gestational age 33 weeks (range 28-40 weeks). The illness was diagnosed at a mean age of 16 days (range 3-33 days). 14 infants (82%) survived. One infant developed NEC because of a volvulus, and another because of an apparently abnormal arterial supply to a segment of bowel. Each of the remaining 15 infants was matched with 3 control infants in order to see whether any factors predisposing to the development of NEC could be identified. Birth asphysia, the use of umbilical catheters, the length of time that these catheters were in place, and complications of catheterization were all significantly more frequent in the infants who developed NEC than in the controls. These findings support the view that hypoxia and ischaemia of the gut wall are important in the pathogenesis of NEC.     

Noma (cancrum oris): questions and answers

Noma (cancrum oris) is an infectious disease which destroys the oro-facial tissues and other neighboring structures in its fulminating course. It affects predominantly children aged 2-16 years in sub-Saharan Africa where the estimated frequency in some communities may vary from one to seven cases per 1000 children. The key risk factors are poverty, malnutrition, poor oral hygiene, deplorable environmental sanitation, close residential proximity to livestock, and infectious diseases, particularly measles. Malnutrition acts synergistically with endemic infections in promoting an immunodeficient state, and noma results from the interaction of general and local factors with a weakened immune system as the common denominator. Acute necrotizing gingivitis (ANG) is considered the antecedent lesion. Current studies suggest that evolution of ANG to noma requires infection by a consortium of microorganisms with Fusobacterium necrophorum and Prevotella intermedia as the suspected key players. Without appropriate treatment, mortality rate is 70-90%. Survivors suffer the two-fold affliction of oro-facial disfigurement and functional impairment. Reconstructive surgery of the resulting deformity is time-consuming and financially prohibitive for the victims who are poor.     

Mineral and/or metal content as critical determinants of particle-induced release of IL-6 and IL-8 from A549 cells

Mineral particles in occupational exposure and ambient air particles may cause adverse health effects in humans. In this study the ability of different stone quarry particles to induce release of the proinflammatory cytokines interleukin-6 (IL-6) and interleukin-8 (IL-8) from human epithelial lung cells (A549) was investigated. Size distribution within the PM10 fractions was quite similar for all particle samples, whereas mineral content and metal composition differed. Particles, containing minerals such as quartz, amphibole, chlorite, and epidote, induced a marked increase in IL-6 and IL-8 release. Particles composed mainly of plagioclase were much less effective. The most potent particle samples exhibited a relatively high content of transition metals such as iron. Exposure to identical masses or surface areas resulted in the same order of potency among the different particle samples. Significant cytotoxicity was observed only at higher concentrations of particle exposure. Thus, mineral composition and/or metal contents of particles from different stone quarries were critical determinants for the marked differences in potency to induce cytokine responses in human epithelial lung cells.