Occurrence of alginate gene sequences among members of the pseudomonad rRNA homology groups I-IV.

Total genomic DNA of 13 pseudomonads representing rRNA homology groups I-IV were screened for sequences homologous to four Pseudomonas aeruginosa alginate (alg) genes by Southern hybridization. Biotinylated probes for three structural genes (algA, algC and algD) and one regulatory gene (algR1) were prepared. Genomic DNA of strains representing group I (P. syringae pv. glycinea, P. viridiflava and P. corrugata) hybridized with all four gene probes. Hybridizing fragments were of differing sizes, indicating that evolutionary divergence among group I members has occurred. P. corrugata has not been reported to synthesize alginate. Genomic DNA from representatives of groups II-IV gave no or very weak hybridization with the probes except for algC. This study indicates that the ability to produce alginic acid as an exopolysaccharide among the pseudomonads is restricted to members of rRNA homology group I in agreement with earlier physiological studies.     

Exopolysaccharides of the plant pathogens Pseudomonas corrugata and Ps. flavescens and the saprophyte Ps. chlororaphis

The rRNA-DNA homology group I pseudomonads Pseudomonas asplenii, Ps. corrugata, Ps. flavescens (plant pathogens), Ps. alcaligenes, Ps. pseudoalcaligenes subsp. pseudoalcaligenes (opportunistic human pathogens), Ps. aureofaciens and Ps. chlororaphis (saprophytes) were examined for their ability to produce exopolysaccharides (EPSs) when cultured on various solid and liquid complex media with glucose, glycerol or gluconate as primary sources of carbon. All three strains (388, 717 and ATCC 29736) of Ps. corrugata produced alginate, a polyuronan. An EPS composed of glucose, fucose, mannose and an unidentified uronic acid substituted with lactic acid was produced by one (B62) of two strains of Ps. flavescens. Of four strains of Ps. chlororaphis tested, only strain NRRL B-2075 produced EPS. The extracellular material purified by anion-exchange chromatography appeared to be a mixture of alginate plus an acidic hexosamine-containing polymer(s). Production of EPS by the other pseudomonads was not supported by any of the media tested.     

Ultrastructural specialization of intestinal epithelium over Peyer's patches in the bonnet monkey, Macaca radiata.

The follicle associated epithelium (FAE) which separates the lymphoid follicle of Peyer's patch from the gut lumen is known to have specialized cells called M cells or "microfold" cells in man and certain animals. These cells are considered to be involved in antigen uptake and transport. Our light microscopic study of the small intestine of bonnet monkeys suggested the presence of such specialised cells in FAE. We have confirmed the presence of M cells in bonnet monkey FAE having ultrastructural features very similar to those of human M cells.     

Effects of intranasal challenge with group A beta haemolytic streptococcus M type 49 in Swiss albino mice

Mice are susceptible to natural infections with streptococci and therefore can serve as suitable animal models to study experimental streptococcal infections. In an earlier study, we had shown the development of pharyngeal colonization, antibody response and histopathological changes in the heart following intranasal (IN) challenge with a rheumatogenic serotype of group A beta haemolytic streptococcus, the M type 18. To determine if nonpharyngitis associated serotypes can also elicit similar responses, 30 Swiss albino mice were challenged intranasally with 2 x 10(7) colony forming units of a skin associated serotype of group A beta haemolytic streptococcus, the M type 49. Pharyngeal colonization varied from 64% (n = 30) in the first week to 69% (n = 16) during the fourth week after IN challenge. Eleven (36.7%) of the 30 animals studied showed antibody response to DNase B (ADNB) with peak titers varying from 150 to 1200 units. Wide variations were seen in ADNB titers in individual mice. Histopathological evidence for cardiac lesions were seen in three animals. The changes were mild and varied from mild to chronic endocardial inflammation to calcification. The study shows that Swiss albino mice are also susceptible to IN challenge with skin associated strains of GABHS and therefore can serve as useful models to study the effects of experimental infection with diverse serotypes of GABHS.     

Effects of agricultural cropping systems on micronutrients transformation

Summary The effect of cropping systems of wheat-maize (WM), wheat-rice (WR), wheat-groundnut (WG), gram-bajra (GrB), potato-guara (PGu), and raya-mash (RaMa) in combination with treatments of dummy (uncultivated area) and applied Zn 0.0 (Zn₀), 2.8 (Zn₁), 5.6 (Zn₂) 11.2 (Zn₃) kg/ha was studied on the transformation of labile Zn fractions: exchangeable (Exch.), adsorbed (TAd) [weakly (WAd), moderately (MAd), strongly (SAd)], and organic matter (OM) in different layers of sandy loam soil. The added Zn stayed largely in the 0–30 cm layer and was associated with the WAd- and OM-Zn fractions. About 70% of the total labile Zn (PAv) remained in the WAd- and OM-Zn, that is, 33 and 39% in 0–15 cm layer, and 33–39% and 31–36% in 16–150 cm layer. All the Zn fractions in 0–15 cm layer, and only of WAd in 16–30 cm layer, significantly increased with rates of Zn addition. These were also significantly higher in Zn_1–3 than Zn₀ and dummy treatments because of the residual Zn. Diverse effects of cropping systems on soil properties, residual Zn, and labile Zn fractions were found. The influence was strong in 0–15 cm layer decreasing gradually with soil depth due largely to differences in Zn requirement, crop intake of various Zn fractions and the cultural practices of the systems. All the crops and rotations appreciabilly responded to Zn application. Uptake of Zn by crops markedly and successively increased with increasing rates of Zn application. The WR caused a significant increase in soil organic matter whereas WR and WM in CaCO₃. The WR, WM and GrB resulted in a decrease in pH while WG and GrB in CaCO₃. The RaMa and PGu maintained much higher residual Zn than other systems. The systems which caused the maximum decrease in Zn fractions were: cereal-cereal (WM) in Exch. legume-millet (GrB) in all the adsorbed, PAv and the Zn associated with CaCO₃, vegetable-legume (PGu) also in MAd and SAd; and cereal-legume (WG) in OM and PAv. Hence GrB, WG and WM in that order will cause the deficiency of Zn much earlier than the other systems due to greater use and or transformation of WAd- andOM-Zn. Such effects were least under RaMa because it increased the WAd-, MAd- and OM-Zn.     

MicroRNA-21 orchestrates high glucose-induced signals to TOR complex 1, resulting in renal cell pathology in diabetes

Hyperglycemia induces a wide array of signaling pathways in the kidney that lead to hypertrophy and matrix expansion, eventually culminating in progressive kidney failure. High glucose-induced reduction of the tumor suppressor protein phosphatase and tensin homolog deleted in chromosome 10 (PTEN) contributes to renal cell hypertrophy and matrix expansion. We identified microRNA-21 (miR-21) as the molecular link between high glucose and PTEN suppression. Renal cortices from OVE26 type 1 diabetic mice showed significantly elevated levels of miR-21 associated with reduced PTEN and increased fibronectin content. In renal mesangial cells, high glucose increased the expression of miR-21, which targeted the 3'-UTR of PTEN mRNA to inhibit PTEN protein expression. Overexpression of miR-21 mimicked the action of high glucose, which included a reduction in PTEN expression and a concomitant increase in Akt phosphorylation. In contrast, expression of miR-21 Sponge, to inhibit endogenous miR-21, prevented down-regulation of PTEN and phosphorylation of Akt induced by high glucose. Interestingly, high glucose-stimulated miR-21 inactivated PRAS40, a negative regulator of TORC1. Finally, miR-21 enhanced high glucose-induced TORC1 activity, resulting in renal cell hypertrophy and fibronectin expression. Thus, our results identify a previously unrecognized function of miR-21 that is the reciprocal regulation of PTEN levels and Akt/TORC1 activity that mediate critical pathologic features of diabetic kidney disease.     

Identification of exopolysaccharides produced by fluorescent pseudomonads associated with commercial mushroom (Agaricus bisporus) production.

The acidic exopolysaccharides (EPSs) from 63 strains of mushroom production-associated fluorescent pseudomonads which were mucoid on Pseudomonas agar F medium (PAF) were isolated, partially purified, and characterized. The strains were originally isolated from discolored lesion which developed postharvest on mushroom (Agaricus bisporus) caps or from commercial lots of mushroom casing medium. An acidic galactoglucan, previously named marginalan, was produced by mucoid strains of the saprophyte Pseudomonas putida and the majority of mucoid strains of saprophytic P. fluorescens (biovars III and V) isolated from casing medium. One biovar II strain (J1) of P. fluorescens produced alginate, a copolymer of mannuronic and guluronic acids, and one strain (H13) produced an apparently unique EPS containing neutral and amino sugars. Of 10 strains of the pathogen "P. gingeri," the causal agent of mushroom ginger blotch, 8 gave mucoid growth on PAF. The "P. gingeri" EPS also was unique in containing both neutral sugar and glucuronic acid. Mucoid, weakly virulent strains of "P. reactans" produced either alginate or marginalan. All 10 strains of the pathogen P. tolaasii, the causal agent of brown blotch of mushrooms were nonnmucoid on PAF. Production of EPS by these 10 strains plus the 2 nonmucoid strains of "P. gingeri" also was negative on several additional solid media as well as in two broth media tested. The results support our previous studies indicating that fluorescent pseudomonads are a rich source of novel EPSs.     

Choice of therapy and mode of delivery in idiopathic intracranial hypertension during pregnancy

Benign intracranial hypertension (BIH) or idiopathic intracranial hypertension (IIH) is a rare disorder of unknown etiology that is most often seen in obese women of reproductive age (19.3/100,000) and is reported only occasionally during pregnancy. Both pregnancy and exogenous estrogens are thought to promote IIH or worsen it. It can occur in any trimester during pregnancy, and the visual outcome is the same as for nonpregnant patients with IIH. There is no increase in fetal wastage; therapeutic abortion to limit its progression is not indicated, and subsequent pregnancies do not increase the risk of recurrence. Most therapies used during the nonpregnant state can also be used during pregnancy. The aim of treatment is to preserve vision and improve symptoms. Treatments include analgesics, diuretics, steroids, and serial lumbar punctures. When medical therapy fails, surgical procedures need to be considered. Although this condition has been reviewed often, the issue of mode of delivery, especially when papilledema has not resolved, is unclear. We report on 3 women with IIH during pregnancy and review the choice of therapy and mode of delivery.     

Rumen and post-rumen fermentation of spent tea leaf protein and other protein sources studied by the nylon bag method

Spent tea leaf (STL) and seven other protein feeds were subjected to microbial fermentation in nylon bags in the rumen of two fistulated buffalo calves and subsequent acid-pepsin digestion in vitro.The STL showed the lowest protein disappearance rate and rumen solubility at 8 h of fermentation. Polyphenols present in STL appear to offer protection to the protein and reduce rumen fermentation. An over-protection could be responsible for the low solubility of the protein in acid—pepsin solution.The high by-pass ability of STL protein appears to make it a suitable feed for growing calves and milking cows.