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 ß-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.

Lemierre's syndrome complicated by an infected branchial cyst.

We present a case of a young man with Lemierre's syndrome characterised by suppurative thrombophlebitis of the internal jugular vein and multiple septic embolic lesions with cavitations in both lungs resulting from an infected branchial cyst which was previously undiagnosed. Lemierre's syndrome is a rare presentation, especially with pulmonary cavitations, but remains a serious illness with a high mortality rate. Early recognition and prompt treatment have significant impact on prognosis. We believe this to be the first case of Lemierre's syndrome complicated by a previously undiagnosed, infected branchial cyst.

Davalintide (AC2307), a novel amylin-mimetic peptide: enhanced pharmacological properties over native amylin to reduce food intake and body weight.

OBJECTIVE: The current set of studies describe the in vivo metabolic actions of the novel amylin-mimetic peptide davalintide (AC2307) in rodents and compares these effects with those of the native peptide. RESEARCH DESIGN AND METHODS: The anti-obesity effects of davalintide were examined after intraperitoneal injection or sustained peripheral infusion through subcutaneously implanted osmotic pumps. The effect of davalintide on food intake after lesioning of the area postrema (AP) and neuronal activation as measured by c-Fos, were also investigated. RESULTS: Similar to amylin, davalintide bound with high affinity to amylin, calcitonin and calcitonin gene-related peptide receptors. Acutely, davalintide displayed greater suppression of dark-cycle feeding and an extended duration of action compared with amylin (23 versus 6 h). Davalintide had no effect on locomotor activity or kaolin consumption at doses that decreased food intake. Davalintide-induced weight loss through infusion was dose dependent, durable up to 8 weeks, fat-specific and lean-sparing, and was associated with a shift in food preference away from high-fat (palatable) chow. Metabolic rate was maintained during active weight loss. Both davalintide and amylin failed to suppress food intake after lesioning of the AP and activated similar brain nuclei, with davalintide displaying an extended duration of c-Fos expression compared with amylin (8 versus 2 h). CONCLUSION: Davalintide displayed enhanced in vivo metabolic activity over amylin while retaining the beneficial properties possessed by the native molecule. In vitro receptor binding, c-Fos expression and AP lesion studies suggest that the metabolic actions of davalintide and amylin occur through activation of similar neuronal pathways.

Drotrecogin alfa (activated): diffusion from clinical trials to clinical practice.

BACKGROUND AND OBJECTIVE: Although the PROWESS trial demonstrated a mortality benefit, subsequent studies in different patient populations have not reproduced the effect. As a result, concerns have been expressed about the clinical effectiveness of drotrecogin alfa (activated). Therefore the aim of this audit was to review the clinical impact of drotrecogin alfa (activated) when used outside clinical trials. METHODS: A retrospective review of ICU charts and medical records of patients who had received drotrecogin alfa (activated) in the five largest users of drotrecogin alfa (activated) in England. Patients characteristics details at ICU admission and vital status at hospital discharge were recorded. The severity of illness was assessed by the APACHE II score (using first 24 h admission data) and the number of organ dysfunctions. Adverse incidents were recorded and any sequence effect explored. RESULTS: In all, 351 patients received drotrecogin alfa (activated) between December 2002 and November 2005. Of those, 201 (57.2%) were male, and 177 (50.4%) were admitted after recent surgery. The patients' average age was 61.8 yr. The mean admission APACHE II score was 23.3 and the average number of dysfunctional organs on admission was 3.3. The hospital mortality was 46.7% (164 deaths). The expected number of deaths calculated by using the APACHE II risk of death was 173 (49.3%) and by number of sepsis induced organ failures 210 (59.7%). Overall, there were 33 (9.4%) adverse incidents. CONCLUSIONS: Expected mortality derived from both the APACHE II score and organ dysfunctions suggests that drotrecogin alfa (activated) does reduce mortality. Serious adverse incidents occurred in 5.1% patients; however, the direct contributing effect of drotrecogin alfa (activated) cannot be established from this type of audit.

Cost analysis of malaria patients in Taikkyi Township Myanmar.

A hospital and clinic-based study was conducted in one malaria endemic area, Taikkyi Township, Yangon Division, Myanmar, for analysis of cost incurred by different types of malaria cases and the factors influencing the cost of illness from July to October 1995. A total of 100 patients admitted to hospital and 100 patients receiving ambulatory care from malaria clinics were interviewed using a structured questionnaire. Total cost of one episode of malaria was estimated to be kyats 559 for ambulatory care, kyats 2582 for an uncomplicated admitted case, kyats 4056 for one episode of cerebral malaria, kyats 4568 for one episode of other severe and complicated malaria and kyats 4758 for one episode of malaria with other disease. This study showed that the cost of illness for patients attending outpatient malaria clinics who received early diagnosis and prompt treatment was four to seven times cheaper than the cost of illness for hospitalized malaria cases. Multivariate analysis revealed the factors that contributed to high cost of care. Duration of illness before getting any type of treatment was the key factor that contributed to high or low cost of care. Long duration of illness before getting any type of treatment can lead to high malaria parasite density, long duration of actual illness and high total attendance cost. Therefore, it is recommended that people from malaria endemic areas should be informed to seek early treatment from health staff, and primary health care services should be made accessible to people who live in malaria endemic areas. The information obtained from this study will be useful in planning future malaria control programs and influencing policy makers to focus on timely and effective treatment of non-severe cases, which can save a large amount of economic loss due to treatment of severe malaria.

Mast cell desensitization to IgE fails to induce a parallel adenosine receptor desensitization.

Desensitization induced by challenge of mast cells with antigen is specific for IgE-dependent signals. During the secretory process mast cells release adenosine, which can induce a desensitization of adenosine receptors. To determine whether adenosine receptors may be desensitized from a previous antigen challenge, mast cells were sensitized with anti-DNP IgE antibody, challenged with DNP-BSA antigen, returned to culture overnight, resensitized, and rechallenged. Previously challenged cells exhibited increased spontaneous beta-hexosaminidase release, but adenosine retained its ability to augment beta-hexosaminidase release. Adenosine enhanced A23187-stimulated release of beta-hexosaminidase in control and previously challenged cells. Leukotriene C4 generation followed a similar pattern. Mastoparan, a direct G protein activator and mast cells secretagogue, produced a doubling of beta-hexosaminidase release in previously challenged cells. Results using other G protein activators were equivocal. Degranulation alone is insufficient to induce adenosine receptor hyposensitization. Whether the hyperresponsiveness to mastoparan is a consequence of uncoupling of IgE receptors from G proteins remains uncertain.