Effects of an Educational Module in Rationalizing Surgical Prophylaxis

Assessment of current antibiotic prescribing patterns is an important step towards appropriate use of antimicrobial agents. This study was planned to know the surgical prophylaxis practices and the influence of educational intervention. In this educational interventional study, only clean and clean-contaminated surgeries were included. Preinterventional study was done by collecting data regarding the use of surgical prophylaxis in the Department of Surgery. After analyzing the preinterventional data, educational intervention was done. A pretest questionnaire was given to all the surgeons to assess knowledge and practice of surgical prophylaxis in our institute. The questionnaire was designed to collect information regarding the use of prophylactic antibiotic, its duration, time of administration, and prevention of surgical site infections (SSI). In our study, third-generation cephalosporin was used in maximum cases in preinterventional analysis and prophylaxis was continued for 3-5 days. Surgeon's decision in selecting a prophylactic agent was based on information taken from departmental colleagues or drug companies. Two or more doses of antibiotic were used even when duration of surgery did not exceed more than two and half hours. Definite improvement was seen after the education where single antibiotic was used as prophylactic drug and the first dose of antibiotic was administered 30 to 60 min before incision. This shows that educational intervention makes a change in antibiotic prescribing habit. Hence, there is an urgent need for adoption of specific guidelines to ensure standardization of surgical antibiotic prophylaxis practices in hospitals.

Conservative Treatment of an Infected Aortic Graft with Antibiotic Irrigation

Conservative management of an aortic graft infection is defined as "the nonresectional treatment of an aortic graft that has an established infection." Incidence of aortic graft infections is 0.5 to 5% and the estimated mortality rate from aortic graft infections ranges from 8 to 27%. We present the case of a 73-year-old male patient with an infected abdominal aortic graft following an emergency ruptured abdominal aortic aneurysm repair. Postemergency repair, he developed ischemic colitis with sigmoid colon perforation leading to fecal peritonitis and secondary sepsis. He developed a large infective collection within the aortic sac growing vancomycin-resistant enterococcus sensitive to linezolid. A percutaneous drain was placed in the aortic sac and this was irrigated with linezolid for a total of 28 days. The patient clinically improved. Overall, 7 months later, follow-up scan shows complete resolution of infection and the patient remains clinically stable. Conventional treatment of aortic graft infections involves an extra-anatomical bypass. Percutaneous drainage and antibiotic use may be used as bridging therapy for surgery or as definitive therapy when surgical treatment is impractical. Most aortic graft infections grow gram-positive cocci, the organisms form a biofilm which is protected from the external environment. Percutaneous drainage and antibiotic irrigation could possibly penetrate the biofilm and eradicate infection. Morris et al conducted a study on 10 patients having irrigation therapy and systemic antibiotic treatment and found a 1-year survival rate of 80%. In conclusion, conservative aortic graft treatment may be an effective alternative where surgical intervention is not suitable.

Edaravone protects rats against oxidative stress and apoptosis in experimentally induced myocardial infarction: Biochemical and ultrastructural evidence

OBJECTIVES

The present study was designed to evaluate the cardioprotective potential of edaravone on oxidative stress, anti-apoptotic, anti-inflammatory and ultrastructure findings in isoproterenol (ISO) induced myocardial infarction (MI) in rats.

METHODS

Rats were pretreated with edaravone (1, 3, 10 mg/kg body weight-1 day-1) intraperitoneally. MI was induced by subcutaneous administration of ISO (85 mg/kg body weight-1) at two doses with 24h interval.

RESULTS

ISO treated rats showed significant increase in the levels of thiobarbituric acid reactive substances (TBARS) and decreased levels of reduced glutathione, glutathione perdoxidase, glutathione reductase and glutathione-S- transferase in the cardiac tissues. Moreover, significant increase in the levels of lactate dehydrogenase (LDH), creatine kinase-MB (CK-MB), C--reactive protein and caspase-3 activity was observed in ISO treated group. Pretreatment of ISO intoxicated rats with edaravone showed significant decrease in the level of TBARS, increased activities of antioxidant enzymes and significantly decreased levels of LDH and CK-MB. Moreover, results also showed decreased C-reactive protein level, caspase-3 activity and maintained ultrastructure of the myocardial cells.

DISCUSSION

Our study suggests that edaravone possess strong cardioprotective potential. Edaravone may have exhibited cardioprotective effects by restoring antioxidant defense mechanism, maintaining integrity of myocardial cell membrane, reducing apoptosis and inflammation against ISO induced MI and associated oxidative stress.

Effect of Sarcosine (a Glycine Transport 1 Inhibitor) and Risperidone (an Atypical antipsychotic Drug) on MK-801 Induced Learning and Memory Deficits in Rats

The present study was carried out to evaluate whether the combined administration of sarcosine with risperidone possess any advantageous effects on dopaminergic and NMDA receptor-mediated glutamatergic neurotransmissions as compared to single drug administration in rats. The Wistar rats were divided into 7 groups each with different treatments. MK-801 (0.1 mg/kg, i.p.) was injected as single dose on 14th day for inducing learning and memory deficits in animals. Sarcosine (300 and 600 mg/kg, i.p.) and risperidone (0.2 mg/kg, i.p.) were administered daily for 14 days. Spatial habituation learning and hole board tests were performed on 14th day followed by measurement of GABA and 5-HT levels in brain tissues of rats. Pretreatment of sarcosine (600 mg/kg, i.p.) non-significantly improved learning and memory deficits induced by non-competitive NMDA receptor antagonist MK-801, significantly increased the GABA and decreased the 5-HT levels (p<0.05). Combined administration of sarcosine (300 mg/kg, i.p.) with risperidone (0.1 mg/kg, i.p.) synergistically improved cognitive deficits significantly, decreased % errors in hole board learning test, and increased centre time, corner time in spatial habituation learning test (p<0.05). The combined administration also potentiated the GABA and decreased 5-HT levels, indicating that the increased synaptic glycine concentrations may enhance NMDA receptor function which is directly linked with increased GABAergic transmission in striatum region and decreased 5-HT levels showed antagonistic action hence, enhancing the cognition. Our results suggest that combined administration of sarcosine with risperidone may strengthen glutamatergic tone in striatum. Thus, it may be a novel regime to improve psychotic symptoms and cognitive deficit in schizophrenia.

Antidepressant Effect of Thymoquinone in Animal Models of Depression

OBJECTIVE

The present study was carried out to determine the role of thymoquinone (TQ) in modulating the levels of neurotransmitter and reducing the oxidative stress in animal models of depression.

MATERIAL AND METHODS

Mice were divided into 5 groups, each group had 6 animals. TQ (20 mg/kg) in corn oil and fluoxetine (10 mg/kg) in normal saline were administered intraperitoneally (i.p.) half an hour before performing behavioural tests. Modified forced swim test (MFST) and tail suspension test (TST) were used to assess the antidepressant effect in mice. Animals were sacrificed and their brains were removed for biochemical estimation after performing behavioural tests.

RESULTS

TQ treatment showed increased swimming, climbing and decreased immobility times in MFST and TST. Combination of TQ with fluoxetine in MFST and TST showed potentiating effect in the present study. A significant elevation of 5-hydroxytryptamine (5-HT) levels was observed following TQ administration in the behavioural models studied. MFST and TST reduced glutathione and elevated TBARS levels in mice. Pre-treatment of TQ restored glutathione and decreased TBARS levels. TQ combination with fluoxetine also showed reduction of TBARS and increased glutathione levels.

CONCLUSION

TQ demonstrated antidepressant effects in MFST and TST respectively in the present study. It further demonstrated antioxidant effects by reducing thiobarbituric acid reactive substance (TBARS) and increasing reduced glutathione (GSH) levels. Although our results are preliminary, further investigations may be required however, based on afore mentioned results, it may be suggested that TQ could be a potential candidate for the management of depression.

A prospective research study of anti-glaucoma drugs prescribing, utilization pattern and adverse drug reaction recording in a university hospital

OBJECTIVE

This study was carried out to evaluate the drug prescribing, utilization pattern and adverse drug reactions recording associated with drugs prescribed to glaucoma patients.

MATERIALS AND METHODS

A total of 50 glaucoma patients were included in the study, based on inclusion and exclusion criteria. All the observations were recorded in drug utilization and ADR recording documentation form.

RESULTS

Out of 50 patients suffering from glaucoma, 38 patients (76%) were diagnosed open angle glaucoma, 4 patients (8%) closed angle glaucoma and 8 patients (16%) post-operative respectively. There were 19 patients (38%) males and 31 patients (62%) were females. The age range between 41-50 years had the maximum number of patients 15 (30%). A total of 17 patients (34%) had family history of glaucoma. Timolol was prescribed to 34 patients (68%), followed by dorzolamide 18 patients (36%) and acetazolamide 14 patients (28%). A total of 32 patients (64%) were prescribed single drug therapy whereas 18 patients (36%) were on multiple drug therapy. A total of 25 patients (50%) reported ADR. In the present study, latanoprost was associated with maximum number of ADRs 9 patients (18%) followed by acetazolamide 7 patients (14%), dorzolamide 4 patients (8%), then timolol 3 patients (6%) and pilocarpine 2 patients (4%). According to Naranjo scale, in 6 patients (24%) the ADR were unlikely, 12 patients (48%) were given possible score, 3 patients (12%) were given probable score, and 4 patients (16%) were given definite scores.

CONCLUSION

In the present study, the maximum patients were in the age group of 41-50 years. The most commonly prescribed drugs were timolol followed by dorzolamide, acetazolamide. Latanoprost was associated with maximum number of ADRs.

Structural evidence for the partially oxidized dipyrromethene and dipyrromethanone forms of the cofactor of porphobilinogen deaminase: structures of the Bacillus megaterium enzyme at near-atomic resolution

The enzyme porphobilinogen deaminase (PBGD; hydroxymethylbilane synthase; EC 2.5.1.61) catalyses an early step of the tetrapyrrole-biosynthesis pathway in which four molecules of the monopyrrole porphobilinogen are condensed to form a linear tetrapyrrole. The enzyme possesses a dipyrromethane cofactor, which is covalently linked by a thioether bridge to an invariant cysteine residue (Cys241 in the Bacillus megaterium enzyme). The cofactor is extended during the reaction by the sequential addition of the four substrate molecules, which are released as a linear tetrapyrrole product. Expression in Escherichia coli of a His-tagged form of B. megaterium PBGD has permitted the X-ray analysis of the enzyme from this species at high resolution, showing that the cofactor becomes progressively oxidized to the dipyrromethene and dipyrromethanone forms. In previously solved PBGD structures, the oxidized cofactor is in the dipyromethenone form, in which both pyrrole rings are approximately coplanar. In contrast, the oxidized cofactor in the B. megaterium enzyme appears to be in the dipyrromethanone form, in which the C atom at the bridging α-position of the outer pyrrole ring is very clearly in a tetrahedral configuration. It is suggested that the pink colour of the freshly purified protein is owing to the presence of the dipyrromethene form of the cofactor which, in the structure reported here, adopts the same conformation as the fully reduced dipyrromethane form.

Escherichia coli signal peptidase recognizes and cleaves the signal sequence of α-amylase originating from Bacillus licheniformis

The gene encoding the α-amylase from Bacillus licheniformis was cloned, with and without the native signal sequence, and expressed in Escherichia coli, resulting in the production of the recombinant protein in the cytoplasm as insoluble but enzymatically active aggregates. Expression with a low concentration of the inducer at low temperature resulted in the production of the recombinant protein in soluble form in a significantly higher amount. The protein produced with signal sequence was exported to the extracellular medium, whereas there was no export of the protein produced from the gene without the signal sequence. Similarly, the α-amylase activity in the culture medium increased with time after induction in case of the protein produced with signal sequence. Molecular mass determinations by MALDI-TOF mass spectrometry and N-terminal amino acid sequencing of the purified recombinant α-amylase from the extracellular medium revealed that the native signal peptide was cleaved by E. coli signal peptidase between Ala28 and Ala29. It seems possible that the signal peptide of α-amylase from B. licheniformis can be used for the secretion of other recombinant proteins produced using the E. coli expression system.

Crystallization and preliminary X-ray characterization of the tetrapyrrole-biosynthetic enzyme porphobilinogen deaminase from Bacillus megaterium

The enzyme porphobilinogen deaminase (PBGD; hydroxymethylbilane synthase; EC 2.5.1.61) catalyses an early step of the tetrapyrrole-biosynthesis pathway in which four molecules of the monopyrrole porphobilinogen are condensed to form a linear tetrapyrrole. The enzyme possesses a dipyrromethane cofactor which is covalently linked by a thioether bridge to an invariant cysteine residue. Expression in Escherichia coli of a His-tagged form of Bacillus megaterium PBGD permitted the crystallization and preliminary X-ray analysis of the enzyme from this species at high resolution.

Intra-aortic balloon pump counterpulsation: are we optimizing the management of cardiogenic shock?

Intra-aortic balloon pump counterpulsation (IABPC) has been used in various forms for decades. The change in physiology brought about by their use is conceptually appealing in managing cardiogenic shock and mechanical complications of myocardial infarction. A common myth is that this method of managing acute cardiological emergencies is to be limited to the realms of this specialist field. However, as medical physicians an appreciation and understanding of this novel therapy is essential not only as a lifesaving measure but also as a bridging therapy to more definitive management in the acute medical setting. IABPC is a safe and under-utilized technique despite featuring in all major international guidelines (ESC and ACC) for the management of cardiogenic shock secondary to acute coronary syndromes. Without awareness of this intervention we may be suboptimally managing patients in the first instance. To improve awareness we examine the evidence supporting the use of the IABPC therapy and the contraindications to their use. Complications and advances in technology are also addressed.

Cloning and characterization of cold, salt and drought inducible C-repeat binding factor gene from a highly cold adapted ecotype of Lepidium latifolium L

The dehydration-responsive element-binding (DREB) protein/C-Repeat Binding Factors (CBFs) belongs to APETALA2 (AP2) family transcription factors that binds to DRE/CRT cis-element in cold-responsive (COR) genes and induce COR genes. CBFs have been isolated and characterized from evolutionarily diverse plant species. CBF pathway is conserved by CBF regulon and the size or the number and kind of target genes vary among freezing sensitive and tolerant plants. Hence, cloning of CBFs from highly freezing tolerant plants such as Lepidium latifolium L. will be useful in understanding the freezing tolerance of this species. In this study, LlCBF, a CBF1 family gene from L. Latifolium L., was cloned using RT-PCR and RACE-PCR. The full length mRNA of LlCBF is 948 bp with an open reading frame of 642 bp, encoding a protein of 213 amino acids with a molecular weight of 23.92 kDa and a theoretical isoelectric point of 4.80. Amino acid sequence analysis showed that LlCBF has an AP2 DNA binding domain, a potential CBF type nuclear localization signal (NLS) and C-terminal acidic domain. Semi-quantitative RT-PCR analysis of LlCBF revealed that this gene is up-regulated by high salt, dehydration and low temperature stresses. The investigation is therefore successful in cloning of a gene having strong homology with CBF transcription factors and responsive to low temperature, high salt and dehydration conditions.

Evaluation of venlafaxine on glucose homeostasis and oxidative stress in diabetic mice

Depression occurs frequently with diabetes affecting the quality of life. All major classes of antidepressants have been shown to have a direct pharmacologic effect on metabolic function, which further worsens glycemic control. There were no reports on the effects of venlafaxine on glucose levels and oxidative stress in diabetic animals. The present study evaluated the effects of venlafaxine (8 and 16 mg/kg per d) on glucose homeostasis along with oxidative stress in brain in diabetic mice (streptozotocin (STZ), 40 mg/kg per d for 5 days). We observed that 21 days of administration of venlafaxine (8 and 16 mg/kg per d) in diabetic mice significantly enhanced swimming in normal and STZ-treated mice with a corresponding reduction in immobility. No significant difference in blood glucose levels was observed in diabetic and normal mice following venlafaxine treatment. Venlafaxine (16 mg/kg) reversed STZ-induced elevated thiobarbituric acid reactive substance (TBARS) levels and also restored the glutathione (GSH) levels in diabetic mice. Venlafaxine (8 and 16 mg/kg) per se does not produce any significant effect in normal animals. The results indicate a dose-dependent antidepressant action of venlafaxine in diabetes-induced depressive mice. Furthermore, the blood glucose levels were not significantly altered in normal and diabetic mice. In addition, venlafaxine exhibited a decrease in TBARS and elevation in GSH levels in mice brain. Venlafaxine drug treatment appears to be safer for depression associated with diabetes.

Effect of zinc in animal models of anxiety, depression and psychosis

The role of zinc (Zn) in anxiety, depression and psychosis was studied in rodents. Zn was administered at doses of 15 and 20 mg/kg intraperitoneally for 7 days. Both doses of Zn reduced the immobility time and increased the swimming time in the modified forced swim test. In the elevated plus maze test, increases in the number of open arm entries and time spent in the open arms were observed with both doses of Zn. In the amphetamine (1 and 2 mg/kg subcutaneously) induced locomotor activity test both doses of Zn produced reduction in the total movement time, mean velocity and stereotypic movements. Extrapyramidal symptoms such as catalepsy in animals are usually observed with conventional antipsychotic agents; but in the present study, Zn at doses of 15 and 20 mg/kg did not produce any cataleptic state in mice. The results of the present study demonstrated the anxiolytic, antidepressant and antipsychotic-like effects of Zn metal ion, which may be due to its N-methyl d-aspartate receptor antagonistic activity. Concurrent administration of a lower dose of Zn with standard existing anxiolytic and antidepressant drugs in this study showed potentiating effect, suggesting that Zn could exert beneficial role when prescribed as add-on medicine in the psychiatric illnesses. The results obtained in this study are preliminary, as further research is required to confirm the exact role of Zn metal in the investigated central nervous system disorders.

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.