DREB1/CBF transcription factors: their structure, function and role in abiotic stress tolerance in plants

Drought, high salinity and low temperature are major abiotic stresses that influence survival, productivity and geographical distribution of many important crops across the globe. Plants respond to these environmental challenges via physiological, cellular and molecular processes, which results in adjusted metabolic and structural alterations. The dehydration-responsiveelement-binding (DREB) protein / C-repeat binding factors (CBFs) belong to APETALA2 (AP2) family transcription factors that bind to DRE/CRT cis-element and regulate the expression of stress-responsive genes. DREB1/CBF genes, therefore, play an important role in increasing stress tolerance in plants and their deployment using transgenic technology seems to be a potential alternative in management of abiotic stresses in crop plants. This review is mainly focussed on the structural characteristics as well as transcriptional regulation of gene expression in response to various abiotic stresses, with particular emphasis on the role of DREB1/CBF regulon in stress-responsive gene expression. The recent progress related to genetic engineering of DREB1/CBF transcription factors in various crops and model plants is also summarized.

What about us? Children's experiences of living with a sibling with spinal cord injury

Spinal cord injury is a life transforming condition that is thought to have an impact on the entire family of the affected individual. The needs and psychological outcomes of siblings of children with spinal cord injury (SCI) have not been researched. The current study focuses on the experiences of children living with a brother or sister with SCI. Eight participants (4 male, 4 female) aged between 7 and 18 years were interviewed using a semi-structured interview, concentrating on their unique experiences and understandings of having a brother or sister with SCI. The qualitative method of Interpretative Phenomenological Analysis (IPA) was used to analyze the data and three main themes were identified: "Life interrupted", "What about me?" and "My safety net". Results are discussed in relation to attachment and coping and adjustment theories. The discussion also highlights the clinical implications for siblings and parents of children affected by SCI, and for professionals who work within pediatric SCI settings.

Neuropharmacological safety evaluation of jigrine: A polyherbal hepatoprotective formulation

Objective

Jigrine is a herbal hepatoprotective formulation containing aqueous extracts of 14 medicinal plants. Present study was designed to evaluate per se neuropharmacological effects of jigrine in mice.

Materials and Methods

Jigrine was evaluated in a number of pharmacological test paradigms, viz. open field arena, actophotometer, hole board, rotarod, traction test, grip strength test, spontaneous alternation behavior, passive avoidance task, and phenobarbital sleeping time.

Results and Conclusions

Jigrine pretreatment (1 and 2 ml/kg, p.o.) did not produce any significant effect as compared to normal saline treated animals and was found to be free from any acute undesirable central effects at these two dose levels.

Effect of l-ornithine l-aspartate against thioacetamide-induced hepatic damage in rats

OBJECTIVE

To investigate the hepatoprotective activity of L-ornithine-L-aspartate against thioacetamide (TAA)-induced hepataopathy in rats.

MATERIALS AND METHODS

The hepatoprotective activity of L-ornithine-L-aspartate (OA) at a dose of 2 g/kg, p.o. for 10 days was evaluated against TAA (250 mg/kg, i.p. for 2 days) induced hepatopathy in rats. Biochemical parameters such as serum aspartate transaminase, alanine transaminase, alkaline phosphatase, bilirubin and glutathione, thiobarbituric acid reactive substances, and protein in liver tissues were estimated to assess the liver function.

RESULTS

TAA-induced pathogenic changes in the levels of the above indices were significantly (P < 0.01) reversed by the OA treatment. OA treatment also exhibited significant restoration of the hepatic architecture and lobular structure in histological evaluation of the rat liver sections.

CONCLUSION

Ornithine aspartate exhibited significant hepatoprotective activity against TAA-induced hepatic damage in rats.

Isolation and characterization of lytic bacteriophages against enterohaemorrhagic Escherichia coli

AIMS

 The objective of this study was to isolate, identify and characterize a collection of lytic bacteriophages capable of infecting enterohaemorrhagic Escherichia coli (EHEC) serotypes.

METHODS AND RESULTS

Phages were isolated from dairy and cattle feedlot manure using E. coli O157, O26 and O111 strains as hosts. Phages were enriched from faecal slurries by culture in 10× trypticase soy broth at 37°C overnight. Phage plaques were obtained by mixing the filtered culture supernatant with molten tryptone agar containing the phage E. coli host strain, pouring the inoculated agar on top of cooled TS agar and incubating the culture overnight. Phages were purified from plaques and screened against additional E. coli and EHEC strains by the efficiency of plating method (EOP). Phage CEV2, and five other phages previously isolated, were able to lyse all of the 15 O157 strains tested with EOP values consistently above 0·001. Two phages were found to be highly effective against strains of E. coli O157 through EOP tests and against O26 strains through spot tests, but not against the O serogroup 111 strains. A cocktail of eight phage that lyse E. coli O157 strains resulted in >5 log CFU ml(-1) reductions at 37°C. Multiplex-PCR revealed that none of these eight phages carried stx1, stx2, hlyA or eaeA genes.

CONCLUSIONS

A cocktail of bacteriophages was capable of lysing most strains of two EHEC serotypes.

SIGNIFICANCE AND IMPACT OF THE STUDY

This collection of phages can be combined and potentially used as an antimicrobial cocktail to inactivate E. coli strains from O serogroups 157 and 26 and reduce their incidence in the food chain.

Risk factors associated with the presence of positive reactions in the SCCIT test in water buffalo around two cities in Punjab, Pakistan

The present study was undertaken to find out the association of certain risk factors with the positive SCCIT (single comparative cervical intradermal tuberculin) test in water buffaloes at Faisalabad and Okara, Pakistan. Seventy-six herds (697 buffaloes) at Faisalabad and 56 (395 buffaloes) at Okara were included in the study. The buffaloes were screened through SCCIT Test. Positive reaction to SCCIT test was recorded in 14% of herds and in 3% of buffaloes. The herds positive for this test were 18% when herds with less than 10 animals were excluded from the analysis and these were 19% when herds with less than 10 buffaloes were excluded. The results of logistic analysis (crude and adjusted) revealed the association of lactating status of buffaloes (OR=1.8) and the presence of cattle at the farm (OR=2-4) with positive SCCIT test. After controlling for the farm, the risk of a positive skin test was 1.5 times higher if we change the location of the animal. Similarly, the controlled analysis (for the farm, breed and other variables) revealed an increased risk (OR=1.1) of a positive skin test with the increase in cattle at the farm. The breed controlled stratified analysis showed the association of a number of cattle at the farm with a positive skin test. It can be concluded from the study that the prevalence of tuberculosis on the basis of a positive skin test is higher at herd level and lower at animal level. Further the risk of a positive skin test is higher when cattle are present at the farm.

The conversion of cholest-7-en-3beta-ol into cholesterol. General comments on the mechanism of the introduction of double bonds in enzymic reactions

Convenient syntheses of 6beta-tritiated Delta(7)-cholestenol and 3alpha-tritiated Delta(7)-cholestene-3beta,5alpha-diol are described. It was shown that the conversion of 6beta-tritiated Delta(7)-cholestenol into cholesterol is accompanied by the complete retention of label. It was unambiguously established that the overall reaction leading to the introduction of the double bond in the 5,6-position in cholesterol occurs via a cis-elimination involving the 5alpha- and 6alpha-hydrogen atoms and that during this process the 6beta-hydrogen atom remains completely undisturbed. Metabolic studies with 3alpha-tritiated Delta(7)-cholestene-3beta,5alpha-diol revealed that under anaerobic conditions the compound is not converted into cholesterol. This observation, coupled with the previous work of Slaytor & Bloch (1965), is interpreted to exclude a hydroxylation-dehydration mechanism for the origin of the 5,6-double bond in cholesterol. It was also shown that under aerobic conditions 3alpha-tritiated Delta(7)-cholestene-3beta,5alpha-diol is efficiently converted into cholesterol and that this conversion occurs through the intermediacy of 7-dehydrocholesterol. Cumulative experimental evidence presented in this paper and elsewhere is used to suggest that the 5,6-double bond in cholesterol originates through an oxygen-dependent dehydrogenation process and a hypothetical mechanism for this and related reactions is outlined.

Antiretroviral regimens in pregnancy and breast-feeding in Botswana

BACKGROUND

The most effective highly active antiretroviral therapy (HAART) to prevent mother-to-child transmission of human immunodeficiency virus type 1 (HIV-1) in pregnancy and its efficacy during breast-feeding are unknown.

METHODS

We randomly assigned 560 HIV-1-infected pregnant women (CD4+ count, > or = 200 cells per cubic millimeter) to receive coformulated abacavir, zidovudine, and lamivudine (the nucleoside reverse-transcriptase inhibitor [NRTI] group) or lopinavir-ritonavir plus zidovudine-lamivudine (the protease-inhibitor group) from 26 to 34 weeks' gestation through planned weaning by 6 months post partum. A total of 170 women with CD4+ counts of less than 200 cells per cubic millimeter received nevirapine plus zidovudine-lamivudine (the observational group). Infants received single-dose nevirapine and 4 weeks of zidovudine.

RESULTS

The rate of virologic suppression to less than 400 copies per milliliter was high and did not differ significantly among the three groups at delivery (96% in the NRTI group, 93% in the protease-inhibitor group, and 94% in the observational group) or throughout the breast-feeding period (92% in the NRTI group, 93% in the protease-inhibitor group, and 95% in the observational group). By 6 months of age, 8 of 709 live-born infants (1.1%) were infected (95% confidence interval [CI], 0.5 to 2.2): 6 were infected in utero (4 in the NRTI group, 1 in the protease-inhibitor group, and 1 in the observational group), and 2 were infected during the breast-feeding period (in the NRTI group). Treatment-limiting adverse events occurred in 2% of women in the NRTI group, 2% of women in the protease-inhibitor group, and 11% of women in the observational group.

CONCLUSIONS

All regimens of HAART from pregnancy through 6 months post partum resulted in high rates of virologic suppression, with an overall rate of mother-to-child transmission of 1.1%. (ClinicalTrials.gov number, NCT00270296.)

Comparison of antinociceptive and antidiabetic effects of sertraline and amitriptyline on streptozotocin-induced diabetic rats

Antidepressants (ADs) are frequently used for the treatment of persistent pain associated with diabetic neuropathy. The aim of this study is to investigate the antinociceptive effects of sertraline (Ser) and amitriptyline (Ami) in diabetic rats, and additionally monitoring their effects on grip strength, blood glucose and percentage glycosylated hemoglobin (GHb%) levels. Streptozotocin (STZ; 55 mg/kg, intraperitoneal [ip]) was injected in rats to induce diabetes. After 7 days, Ser (30 mg/kg) or Ami (15 mg/kg) was administered in diabetic rats orally. After 28 days drug treatment, the antinociceptive effects were evaluated using hot plate test both in diabetic and non-diabetic rats. The effects of these drugs on grip strength, blood glucose and GHb% were also measured. Ser and Ami showed antinociceptive effects in diabetic and non-diabetic rats. Both the drugs increased the grip strength reduction in STZ-induced diabetic rats. Ser reduces and Ami increases the serum glucose levels in diabetic and normal rats. Administration of Ami per se increased GHb% levels, while Ser per se has no effects. The effects of Ser (30 mg/kg, per os [po]) on glucose, GHb% and antinociceptive action on hot plate test showed an association between improved blood glucose levels and analgesia. However, the results of Ami treatment are controversial and needs further studies.