Expression and protective effects of urocortin in cardiac myocytes

Reverse transcription PCR showed that mRNA encoding the CRH-like molecule, urocortin, is expressed in a rat cardiac myocyte cell line and in primary cultures of cardiac myocytes. Identity of the amplified with the published sequence was established by restriction mapping and direct sequencing. Expression of urocortin mRNA was increased 12-18 h after thermal injury. Urocortin peptide protected cardiac myocytes from cell death induced by hypoxia. The data suggest that urocortin is an endogenous cardiac myocyte peptide which modulates the cellular response to stress.

New-onset diabetes and ketoacidosis with atypical antipsychotics

Information from the Ohio Department of Mental Health (ODMH) database was reviewed retrospectively to identify patients at the Cincinnati center treated with an atypical antipsychotic and who had also been evaluated or treated for diabetes mellitus. Blood glucose levels, glucose tolerance, or other evaluations of diabetes had been conducted in 14 of the 126 patients treated with atypical antipsychotics. In 11 of the 14, new-onset, acute, and marked glucose intolerance developed after treatment with clozapine, olanzapine or quetiapine. Of these, six patients required insulin therapy (four only transiently) and five patients developed diabetic ketoacidosis (DKA). Also, glucose metabolism was labile in all cases, and was transient in two cases with subsequent resolution despite on-going antipsychotic therapy. Certain atypical antipsychotics may be associated with new-onset glucose intolerance, including acute diabetes and ketoacidosis. Monitoring for changes in blood glucose levels in patients taking atypical antipsychotics may be indicated. More systematic study data are clearly needed.

Synergistic metabolic benefits of an exenatide analogue and cholecystokinin in diet-induced obese and leptin-deficient rodents

AIM

To test the impact of cholecystokinin (CCK) plus either amylin or a glucagon-like peptide-1 receptor (GLP-1R) agonist on metabolic variables in diet-induced obese (DIO) rodents.

METHODS

A stabilized acetylated version of CCK-8 (Ac-Y*-CCK-8), selective CCK1 receptor (CCK1R) or CCK2 receptor (CCK2R) agonists, amylin or the GLP-1R agonist and exenatide analogue AC3174 were administered in select combinations via continuous subcutaneous infusion to DIO rats for 14 days, or Lep(ob) /Lep(ob) mice for 28 days, and metabolic variables were assessed.

RESULTS

Combined administration of Ac-Y*-CCK-8 with either amylin or AC3174 induced greater than additive weight loss in DIO rats, with the overall magnitude of effect being greater with AC3174 + Ac-Y*-CCK-8 treatment. Co-infusion of AC3174 with a specific CCK1R agonist, but not a CCK2R agonist, recapitulated the weight loss mediated by AC3174 + Ac-Y*-CCK-8 in DIO rats, suggesting that synergy is mediated by CCK1R activation. In a 4 × 4 full-factorial response surface methodology study in DIO rats, a synergistic interaction between AC3174 and the CCK1R-selective agonist on body weight and food intake was noted. Co-administration of AC3174 and the CCK1R-selective agonist to obese diabetic Lep(ob) /Lep(ob) mice elicited a significantly greater reduction in percentage of glycated haemoglobin and food intake relative to the sum effects of monotherapy groups.

CONCLUSIONS

The anti-obesity and antidiabetic potential of combined GLP-1R and CCK1R agonism is an approach that warrants further investigation.

Anti-platelet agents and surgical delay in elderly patients with hip fractures

PURPOSE

To assess the risk of surgical delay in elderly hip fracture patients on anti-platelet agents.

METHODS

Records of 180 patients aged over 65 years with either an intertrochanteric or femoral neck fracture were reviewed. The clopidogrel group included 10 patients on clopidogrel alone and 11 others on clopidogrel and aspirin, whereas the control group included 69 on aspirin alone and the remaining 90 not on any anti-coagulants. The 2 groups were compared with regard to time to surgery, preoperative American Society of Anesthesiologists (ASA) score, pre- and post-operative haemoglobin levels, in-patient complication rates, duration of hospital stay, and 30-day mortality.

RESULTS

In the clopidogrel and control groups respectively, the mean times to surgery were 7.2 and 2.1 days (p=0.03, t-test), the mean preoperative ASA scores were 3.35 and 2.8 (p=0.29, t-test), the mean preoperative haemoglobin levels were 119 and 115 g/l (p=0.5, t-test), the mean postoperative haemoglobin levels were 98 and 96 g/l (p=0.68, t-test), the mean durations of hospital stay were 7.4 and 3.1 days (p=0.02, t-test). The 30-day mortalities were 6/21 (29%) and 6/159 (4%) [p=0.0003, Fisher's exact test].

CONCLUSION

Surgical delay in elderly patients on anti-platelet agents with hip fracture was associated with higher mortality. Despite the risk of increased blood loss, we suggest early surgery be carried out by an experienced surgeon to expedite the operating time. Pooled platelets should be given intravenously one to 2 hours preoperatively.

New acetogenin peroxides from the Indian sponge Acarnus bicladotylota

Two new cyclic peroxides (1 and 2) and the known metabolite 3 have been found in the organic extract of the Indian sponge Acarnus bicladotylota. The structure of the new products has been assured by chemical and spectroscopic methods. The absolute stereochemistry of 1-3 has been determined by Mosher's method on the semisynthetic derivative 4.

Meaningful differences in maternal smoking behaviour during pregnancy: implications for infant behavioural vulnerability

BACKGROUND

Smoking during pregnancy has been consistently associated with risk of problem behaviour in offspring. There is debate about whether this association reflects a teratological effect or is a marker for problematic maternal characteristics. We test these "competing" hypotheses by examining whether (1) exposure is associated with an early risk pathway by testing its association with infant temperamental difficultness, and (2) whether pregnancy quitting is associated with an early protective pathway, testing its association with easy infant temperament.

METHODS

We used the 9-month-old sweep of the Millennium Cohort Study, a cohort of over 18,000 infants born in 2000-2. Mothers were classified as pregnancy non-smokers, quitters and light or heavy smokers. Temperamental positive mood, receptivity to novelty and regularity were assessed with the Carey Infant Temperament Scale.

RESULTS

Pregnancy quitters had infants with the highest scores of easy temperament and heavy smokers had infants with the lowest scores (F = 28.51, p<0.001). Pregnancy smoking also predicted difficult temperament: heavy smoking was associated with increased risk of low positive mood (OR = 1.17, p = 0.09). In contrast, pregnancy quitting exerted a protective effect with decreased risk of distress to novelty (OR = 0.79, p<0.01) and irregularity (OR = 0.89, p = 0.02) in these infants.

CONCLUSIONS

Pathways from pregnancy smoking to offspring behaviour are complex and multi-determined. These findings suggest that both exposure and maternal characteristics associated with pregnancy smoking status contribute to offspring behavioural patterns. Research that characterises differences between quitters and persistent smokers and examines the role of these differences in prediction of early vulnerabilities and problems in adaptation over time will be important for elucidating these pathways.

Heterogeneity of specific-IgE responses in workers sensitized to acid anhydride compounds

Acid anhydride compounds cause IgE-mediated respiratory sensitization in the workplace. In this study reaginic responses in four workers sensitized to phthalic anhydride (PA), hexahydrophthalic (HHPA), or himic anhydride (HA) were determined by direct RAST by use of PA-human serum albumin (HSA), HPPA-HSA, and HA-HSA methylcellulose disc substrates. RAST inhibition of binding to anhydride-HSA substrates was done with various concentrations of sodium salts, lysine, and HSA conjugates of PA, HHPA, HA, and trimellitic anhydride (TMA) in order to characterize cross-reactivity and specificity of humoral responses in these workers. Molar concentrations of anhydride bound to lysine and HSA carriers were assayed by protein hydrolysis followed by gas chromatographic analysis. Significant direct RAST binding against PA-HSA, HHPA-HSA, and HA-HSA was found in all four workers. PA-HSA-IgE binding in one PA-sensitive worker (no. 1) was inhibited significantly by PA-HSA alone and not by sodium PA or PA lysine. In contrast, another PA-sensitized worker (no. 2) exhibited 50% inhibition of PA-HSA binding by PA-HSA (1 X 10(-9) M), PA-lysine (7 X 10(-8) M), and NaPA (1 X 10(-7) M); no inhibition of PA-HSA by heterologous HHPA-, HA-, or TMA-inhibitory reagents was found in either of the PA workers. RAST binding to HHPA-HSA in the HHPA-sensitive worker was inhibited by HHPA-HSA alone.(ABSTRACT TRUNCATED AT 250 WORDS)

Improving services for disadvantaged childbearing women

BACKGROUND

Tackling health inequalities is high on the political agenda of the Labour government. The government wants to reduce inequalities through policies based on evidence, the health of childbearing women and their babies being priority areas for action. National Service Frameworks (NSFs) are being set up to ensure high quality services for all groups. The External Working Group looking into maternity services for the Children's NSF seeks evidence upon which to plan strategies for all women, while focusing attention on the most disadvantaged. Wide differentials are noted between high- and low-income groups in the outcomes of pregnancy and the health of babies. The worst outcomes appear to be concentrated in small subgroups of disadvantaged women.

AIM

To report on a review of studies of interventions improving perinatal outcomes for disadvantaged women, to inform policy and practice around the organization and delivery of statutory services in the UK.

METHOD

We searched six relevant databases for reviews, intervention studies, audits and descriptions of services reporting outcomes for disadvantaged groups of women, published between 1990 and 2003. Synthesis was performed around what works and what does not work. Gaps in the evidence base were identified.

RESULTS

We found limited evidence of effective and promising interventions for childbearing women from minority ethnic groups, women experiencing domestic violence, women with mental health illness and HIV infected women. Few studies were well-designed or powered to detect effectiveness. There were no studies of interventions for women prisoners, homeless women and travellers.

CONCLUSIONS

Searching for intervention studies primarily by participant subgroup has brought in evidence from few well-designed studies on which to plan policy. Combining this approach with searching for intervention studies addressing behaviour like smoking, and needs like social support, may provide further evidence to tackle inequalities in the perinatal period.

Rethinking research in breast-feeding: a critique of the evidence base identified in a systematic review of interventions to promote and support breast-feeding

Objective

To appraise critically the relevance and value of the evidence base to promote and support the duration of breast-feeding, with a specific focus on disadvantaged groups.

Design

A systematic review was conducted of intervention studies relevant to enhancing the duration of breast-feeding; topics included public health, public policy, clinical issues, and education, training and practice change. A systematic search was conducted. Eighty studies met the inclusion criteria. Data were systematically extracted and analysed. Full results and recommendations are reported elsewhere. Here a critique of the evidence base – topics, quality and gaps – is reported.

Results

Many studies were substantially methodologically flawed, with problems including small sample sizes, inconsistent definitions of breast-feeding and lack of appropriate outcomes. Few were based on relevant theory. Only a small number of included studies (10%) were conducted in the UK. Very few targeted disadvantaged subgroups of women. No studies of policy initiatives or of community interventions were identified. There were virtually no robust studies of interventions to prevent and treat common clinical problems, or of strategies related to women's health issues. Studies of health professional education and practice change were limited. Cost-effectiveness studies were rare.

Conclusions

Policy goals both in the UK and internationally support exclusive breast-feeding until 6 months of age. The evidence base to enable women to continue to breast-feed needs to be strengthened to include robust evaluations of policies and practices related to breast-feeding; a step change is needed in the quality and quantity of research funded.

New scalaranes from the nudibranch Glossodoris atromarginata and its sponge prey

Two new scalaranes (1 and 2) have been isolated from the dorid nudibranch Glossodoris atromarginataand its prey. The structures were deteremined by spectral techniques and confirmed by chemical methods. Compounds 1 and 3 showed selective cytotoxic activity against human thyroid carcinoma.

Quinazolines as inhibitors of dihydrofolate reductase. 3. Analogs of pteroic and isopteroic acids

A series of 19 quinazoline analogs of pteroic and isopteroic acid was prepared with particular emphasis being placed upon carboxylic acid esters. Each compound was evaluated as an inhibitor of the dihydrofolate reductases from rat liver as well as from Streptococcus faecium. Several of the more potent inhibitors were found to be inactive against L1210 leukemia in mice at low dose levels and were lethal to mice at 100 mg/kg. Six compounds were also evaluated for antimalarial activity against Plasmodium berghei in mice. Three of these were found to be curative at higher levels, while the remaining compounds were found to be toxic.

A novel long-acting glucose-dependent insulinotropic peptide analogue: enhanced efficacy in normal and diabetic rodents

AIM

Glucose-dependent insulinotropic peptide (GIP) is an incretin hormone that is released from intestinal K cells in response to nutrient ingestion. We aimed to investigate the therapeutic potential of the novel N- and C-terminally modified GIP analogue AC163794.

METHODS

AC163794 was synthesized by solid-phase peptide synthesis. Design involved the substitution of the C-terminus tail region of the dipeptidyl peptidase IV (DPP-IV)-resistant GIP analogue [d-Ala(2) ]GIP(1-42) with the unique nine amino acid tail region of exenatide. The functional activity and binding of AC163794 to the GIP receptor were evaluated in RIN-m5F β-cells. In vitro metabolic stability was tested in human plasma and kidney membrane preparations. Acute insulinotropic effects were investigated in isolated mouse islets and during an intravenous glucose tolerance test in normal and diabetic Zucker fatty diabetic (ZDF) rats. The biological actions of AC163794 were comprehensively assessed in normal, ob/ob and high-fat-fed streptozotocin (STZ)-induced diabetic mice. Acute glucoregulatory effects of AC163794 were tested in diet-induced obese mice treated subchronically with AC3174, the exendatide analogue [Leu(14) ] exenatide. Human GIP or [d-Ala(2) ]GIP(1-42) were used for comparison.

RESULTS

AC163794 exhibited nanomolar functional GIP receptor potency in vitro similar to GIP and [d-Ala(2) ]GIP(1-42). AC163794 was metabolically more stable in vitro and displayed longer duration of insulinotropic action in vivo versus GIP and [d-Ala(2) ]GIP(1-42). In diabetic mice, AC163794 improved HbA1c through enhanced insulinotropic action, partial restoration of pancreatic insulin content and improved insulin sensitivity with no adverse effects on fat storage and metabolism. AC163794 provided additional baseline glucose-lowering when injected to mice treated with AC3174.

CONCLUSIONS

These studies support the potential use of a novel GIP analogue AC163794 for the treatment of type 2 diabetes.

Determination of geometric orientation of adsorbed cinchonidine on Pt and Fe and quiphos on Pt nanoclusters via DRIFTS

Platinum nanoclusters modified with cinchonidine have been employed as 'quasi-homogeneous' catalysts for the hydrogenation of ethyl pyruvate and have demonstrated exceptional activities while the ee's of these systems are currently inferior to the traditional Pt/Al2O3 heterogeneous system. For the bulk systems it has been shown that the orientation of the modifier on the metal surface is a critical parameter influencing catalytically induced enantioselectivity. It has been speculated that the lower observed ee's for the nanocluster systems are a result of the modifier assuming an orientation unfavorable for inducing enantioselectivity due to the lack of large numbers of planar metal atoms. Using DRIFTS (diffuse reflectance infra-red Fourier transform spectroscopy) analysis of samples together with geometry optimization and IR modelling we have studied the orientation of cinchonidine on Pt and Fe nanoclusters and additionally the man-made ligand quiphos on Pt nanoclusters. It has been determined that cinchonidine can adsorb on Pt and Fe nanoclusters in both 'flat' and 'tilted' modes, while quiphos can be adsorbed on Pt only via the 'pi-bonded' mode. These studies thus provide an insight into modifier orientation on nanocluster surfaces that can be extended to a wide range of potential modifiers and facilitate a better understanding of the origin of enantioselectivity with these 'quasi-homogeneous' catalyst systems.

Photolytic cleavage of sulfonamide bonds

It has been found that the sulfonamide bond is relatively susceptible to photolytic cleavage. The breakdown was effected either by irradiation with a source having a continuous emission above the wavelengths of 1800 angstroms or by another source emitting principally at 2537 angstroms. Less destruction of the amino acids was seen with the latter relative to the sulfonamide bond cleavage. The cleavage was not effected by irradiation at wavelengths greater than about 3000 angstroms. Side reactions were noted involving decarboxylation, demination, and destruction of certain susceptible amino acids such as tryptophan. In only one case was a product found that arose from cleavage of a carboxamide bond; glycyltyrosine gave glycine and tyrosine upon irradiation. A yield of 75 percent of the corresponding amino acid has been obtained by irradiation of tosylhistidine; yields of 75 to 100 percent have been obtained from sulfamic acid (NH(2)SO(3)H). A qualitative method for identifying sulfonylated amino acids is described.

Interactions of amylinergic and melanocortinergic systems in the control of food intake and body weight in rodents

AIMS

Amylinergic and melanocortinergic systems have each been implicated in energy balance regulation. We examined the interactive effects of both systems using gene knockout and pharmacological approaches.

METHODS

Acute food consumption was measured in overnight fasted male wild-type (WT) and melanocortin-4 receptor (MC-4R) deficient rats and in male and female WT and amylin knockout mice (AmyKO). Changes in food intake, body weight and composition in male WT and MC-4R deficient rats and in male diet-induced obese (DIO) rats. Pharmacological treatments included either rat amylin, murine leptin and/or the MC-4R agonist, Ac-R[CEH-dF-RWC]-amide.

RESULTS

Amylin (10 µg/kg, IP) decreased food intake in WT but not in MC-4R deficient rats (30 and 60 min post-injection). Ac-R[CEH-dF-RWC]-amide (100 µg/kg, IP) suppressed food intake similarly in male WT and AmyKO, but was ineffective in female AmyKO. Amylin (50 µg/kg/day for 28 days) and leptin (125 µg/kg/day) synergistically reduced food intake and body weight in WT and MC-4R deficient rats to a similar extent. Amylin (100 µg/kg) combined with Ac-R[CEH-dF-RWC]-amide (100 µg/kg, IP) decreased acute food intake over 3 h to a greater extent than either agent alone in fasted mice. In DIO rats, additive anorexigenic, weight- and fat-lowering effects were observed over 12 days with the combination of rat amylin (50 µg/kg/day) and Ac-R[CEH-dF-RWC]-amide (2.3 mg/kg, SC injected daily).

CONCLUSIONS

Although amylin's acute anorexigenic effects are somewhat blunted in MC-4R deficiency and those of MC-4R agonism in amylin deficiency, these effects are surmountable with pharmacological administration lending therapeutic potential to combined amylin/melanocortin agonism for obesity.

Hypokalemia after normal doses of neubulized albuterol (salbutamol)

The cases of two asthmatic patients who became hypokalemic after inhalation of normal doses of albuterol are presented. One patient was symptomatic and the other had only electrocardiographic changes. Both were treated successfully with oral potassium. Albuterol-induced hypokalemia and its potential cardiac toxicity are discussed briefly.

Antimicrobial activity of marine sponge Clathria indica (Dendy, 1889)

Sponges are sessile filter feeders that have developed efficient defense mechanisms against foreign invaders such as viruses, bacteria or eukaryotic organisms. Antimicrobial peptides are known as major components of the innate immune defense system in marine invertebrates. The aim of the present work was to study the antimicrobial properties of the Indian sponge Clathria indica with special reference to the identification of antimicrobial peptides. Crude methanolic extract and its chloroform, n-butanol and aqueous fractions were tested against 16 human pathogens which include eleven bacteria with four of them being multidrug resistant and five pathogenic fungi. All fractions showed effective antibacterial activity against common and multidrug-resistant Salmonella typhi and antifungal activity against C. albicans and C. neoformans. However, they were ineffective against Escherichia coli, Pseudomonas aeruginosa, Streptococcus pyogenes and Staphylococcus aureus. Chloroform fraction being the most potent among the fractions tested on chemical investigation was indicative of the presence of peptides as evidenced by ninhydrin positive spots on TLC and presence of peptide bonds by NMR. Its ESI-MS showed presence of several peptides in the range of m/z 850 to 980. Structure of three peptides has been tentatively assigned by ESI-MS/MS or tandem mass analysis, on the basis of the amino acid sequence established. The results clearly show that the sponge C. indica represent an interesting source of marine invertebrates-derived antimicrobial peptides in the development of new strategies to treat various infectious diseases.