An increased frequency of NK cell receptor and HLA-C group 1 combinations in early-onset type 1 diabetes

AIMS/HYPOTHESIS

Natural killer (NK) cells serve as primary immune surveillance and are partially regulated by combinations of killer immunoglobulin-like receptor (KIR) genes and their HLA class I ligands. Alterations in NK cell activity have been associated with type 1 diabetes. The aim of this study was to determine whether KIR-HLA class I gene frequency: (1) is altered in a current population with type 1 diabetes compared with healthy controls; and (2) has changed over the half century in which the incidence of type 1 diabetes has increased rapidly.

METHODS

KIR-HLA class I gene frequencies were compared in 551 individuals diagnosed with type 1 diabetes ≤ 15 years of age (394 in a current cohort and 157 from the historical 'Golden Years' cohort) and 168 healthy controls. The overall balance of activation and inhibition was analysed using KIR-HLA genotype models.

RESULTS

Children with type 1 diabetes who were positive for KIR2DS2/KIR2DL2 and KIR2DL3 were more often homozygous for HLA-C group 1 and this effect was strongest in children diagnosed with diabetes before the age of 5 years (p = 0.003, corrected p [p (corr)] = 0.012) and (p = 0.001, p (corr) = 0.004), respectively. Children with type 1 diabetes have fewer inhibitory KIRs with their corresponding ligands compared with healthy controls (p = 1.9 × 10(-4)). This pattern of NK activation has not changed significantly in individuals with type 1 diabetes over the last half century.

CONCLUSIONS/INTERPRETATION

Activating combinations of KIR-HLA genes are more frequent in young children with type 1 diabetes diagnosed in the first 5 years of life, suggesting that NK cell responses may be altered in this group.

A phase I study of the combination of intravenous Reolysin (REO) and gemcitabine (GEM) in patients (pts) with advanced cancer

3584

Background: REO (reovirus serotype 3) is a Dearing strain, naturally occurring, non-enveloped virus with limited pathogenecity in humans. REO replicates specifically in transformed Ras-activated cells due to inhibition of the dsRNA-activated protein kinase, resulting in cell-lysis. GEM has shown efficacy in a wide range of tumors commonly driven by activated Ras, and causes cell cycle arrest in S phase. Results from isobologram analysis suggest potential synergies of REO and GEM. Methods: This open-label, dose-escalating, two-centre phase-I trial studied the combination of iv REO, d1–5 and iv GEM, d1 and 8, qw3. The REO starting dose was 3x109 TCID50 over 1-hour, increasing in successive cohorts and GEM was given at a fixed dose of 1,000 mg/m2 over 30-min. Endpoints were the maximum tolerated dose (MTD), dose limiting toxicity (DLT), and safety profile of REOGEM and to establish a RP2D. Secondary endpoints were to evaluate the immune response, to evaluate pharmacokinetics of REOGEM and to describe any antitumor activity. Results: Since July 2007, 15 heavily pre-treated pts with disease progression prior to trial entry (9M/6F, median age 56 years, ECOG 0/1: 3/12) were entered into this trial. After 2 pts had Grade >3 toxicities during the first cycle (1 pt: GGT and Trop-I increase and PD; 1 pt: Trop-I increase and unspecific ST-changes) considered probably related to both agents the protocol was amended and the dose of REO was adjusted to 1x109 TCID50, d1 of each cycle (C-1) and increased in subsequent cohorts to 3x109, 1x1010, and 3x1010 TCID50. In total 45 cycles were administered (median 3) resulting in mild and expected toxicities including fever, headaches, rhinorrhea, fatigue and myelosupression. The MTD was not reached. Of the 10 pts evaluable for response, 2 pts (breast and nasopharyngeal) had PR and/or clinical response and 5 pts had SD for 4–8 cycles, amounting for a total disease control rate (CR+PR+SD) of 70%. Conclusions: The combination of REOGEM was well tolerated and resulted in disease control for a majority of pts. A RP2D, of REO 3x1010, d1 and GEM 1000mg/m2, d1 and 8, qw3, was recommended and phase-2 trials are underway.

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Diabetic complications and glycaemic control in remote North Africa

BACKGROUND

Delivery of diabetes services in resource-poor areas of Africa is difficult. Control is often poor and complications are common. However, adequate robust surveys are uncommon, particularly in remote rural areas. This makes needs assessment difficult and health-care planning impossible.

AIM

To accurately assess the glycaemic control and burden of complications in a group of diabetic patients from a remote area of a resource-limited north African country.

DESIGN

Prospective cohort study.

METHODS

Over a 6-week period, all patients attending the diabetic clinic at Mekelle Hospital in northern Ethiopia were intensively assessed, using imported western technology as necessary. Glycated haemoglobin (HbA(1c)), lipid profile, serum creatinine and urinary albumin-creatinine ratio were measured. Complications were assessed as accurately as possible, including examination of fundi by an ophthalmic specialist, and biosthesiometry for neuropathy.

RESULTS

There were 105 patients, mean (+/- SD) age 41 +/- 16 years and diabetes duration 7 +/- 6 years. There were 74 (70%) males, and 69 (66%) on insulin. Median body mass index was low at 20.6 kg/m(2), but mean HbA(1c) high at 11.3 +/- 2.8% (68% had an HbA(1c) over 10.0%). Cataract (12%), retinopathy (21%), neuropathy (41%) and microalbuminuria (51%) were common; but nephropathy (2%) was rare, as was large vessel disease (6% had peripheral vascular disease, and none had coronary artery disease or cerebrovascular disease). Risk factors such as hypertension (5%) and smoking (2%) were uncommon, and lipid profiles were generally good.

DISCUSSION

We conclude that in this severely resource-limited area of North Africa, glycaemic control amongst diabetic patients is very poor. Neuropathy, retinopathy and microalbuminuria are common; but large vessel disease risk factors are beneficial, and macroangiopathy prevalence is low. Scattered populations, shortage of drugs and insulin and lack of diabetes team care are major factors behind these serious issues of diabetic control and complications.

Influence of diabetes on the maintenance of sinus rhythm after a successful direct current cardioversion in patients with atrial fibrillation

AIM

To determine independent risk factors for recurrence of atrial fibrillation (AF) after a successful direct current (DC) cardioversion in patients with and without diabetes.

DESIGN

We retrospectively analysed the outcome in patients recently diagnosed with persistent AF.

METHODS

Of 364 patients included, 289 had a successful direct current (DC) cardioversion. We compared 42 (14.5%) patients known to have diabetes to 247 (85.5%) without. Patients were reviewed in outpatient clinic with assessment of heart rhythm clinically and by electrocardiogram. Median follow-up after DC cardioversion was 74 days [interquartile range (IQR) 69-78 days].

RESULTS

When reviewed in outpatient clinic, only 63.7% (185 of 289) were still in sinus rhythm (SR). Of the group without diabetes, 66.8% (165 of 247) remained in SR vs. 45.2% (19 of 42) of the group with diabetes (P = 0.005). Binary logistic regression analysis showed duration of AF (P < 0.0001) and the presence of diabetes (P = 0.019) have been independent risk factors for recurrence of AF.

DISCUSSION

Presence of diabetes and the longer duration of AF were independent risk factors for the recurrence of AF after a successful DC cardioversion.

Antiplatelet drug use in a diabetic clinic

BACKGROUND

There are definite indications for antiplatelet therapy in diabetes in the presence of large-vessel disease, but in the absence of large-vessel disease, the evidence is less clear. There is also evidence that antiplatelet therapy is under-prescribed.

AIM

To investigate the use of antiplatelet drugs in patients attending a diabetic clinic in a large teaching hospital.

DESIGN

Retrospective case-note survey.

METHODS

We examined the case-notes of 300 consecutive diabetic patients, to determine whether antiplatelet therapy was being used in appropriate patients, including those with established large-vessel disease, hypertension and nephropathy or microalbuminuria.

RESULTS

The patients were of mean +/- SD age 61 +/- 13 years, diabetes duration 10 +/- 8 years, BMI 31.4 +/- 6.7 kg/m(2) and HbA(1c) 8.3 +/- 1.5%; 276 (92%) had type 2 diabetes, and 162 (54%) were male. Antiplatelet drugs were being taken by 157 (52%) who fulfilled the survey standard for treatment; a further 83 (28%) met the survey standard but were not receiving treatment, of whom 48 (16% of the total group) had no valid contraindication.

DISCUSSION

A significant minority of diabetic patients are being denied antiplatelet drugs despite good indications.

Pharmacodynamic and safety study of reolysin in patients with advanced solid tumors

14004

Background: Reolysin is an intravenous formulation of reovirus serotype 3 - Dearing strain which is a double stranded RNA non-enveloped icosahedral virus capable of inducing cytopathic effects in cancer cells that have an activating mutation in the ras protooncogene. Pre clinical testing has identified cancer cell lines as being susceptible to reovirus infection. Methods: This was an open- label single center phase I safety and dose escalation trial of reolysin administered intravenously over 1 hour on day 0 in a 28 day cycle. Dose escalations were in half log increments. Serum for neutralizing antibody (NA) was drawn at baseline, and days (d) 1, 7, 14, 21, and 28, and serum, stool, saliva, and urine for viral shedding (by RT-PCR) were sampled on d 1,7,14,21, and 28. Response was assessed by imaging studies after 1, 3, 5, and 7 cycles. Results: 18 patients (pt); median age 57 (40–72) years; performance status 0–1; diagnoses - ovarian (6), colorectal (5), and others (7) received 27 cycles of reolysin (median 1, range 1–7) in 6 dose cohorts of 1x108, 3x108, 1x109, 3x109, 1x1010, and 3x1010 tissue culture infective dose (TCID)50. No protocol defined dose limiting toxicities were observed. Drug related grade 2 toxicities included chills (2 pt), and fatigue (3 pt). The only grade 3 event was fever in cycle 7 in a 57 year old woman with progressive breast cancer, treated at a dose of 1x1010 TCID50. She was noted to have 28.5% shrinkage in objective tumor volume. An additional 7 pt had stable disease (SD). No NA was detectable in the serum in any pt at baseline; however all pt developed NA (on d 5 in 5 pt, d 8 in 11 pt, d 14 in 1 pt, and d 28 in 1 pt) during the course of the study. Viral shedding was observed in serum - 5 pt, stool - 3 pt, saliva - 3 pt, and urine - 4 pt. Of interest, 4 of 5 pt with viral shedding had SD as their best response. However, there was no observed relationship between NA formation and SD. Conclusion: Reolysin administered as a one hour infusion on a monthly schedule is safe and well-tolerated even in multiple doses. This preliminary data suggests there is anti-tumor activity of reolysin as a single agent, and warrants further studies either alone or in combination with cytotoxic chemotherapy.

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Feasibility study on the MammoSite in early-stage breast cancer: Initial experience

The aims of this study were to evaluate the feasibility, practicality, efficacy and safety of the delivery of accelerated partial breast irradiation using the MammoSite for the boost phase. Six patients aged 53-69 years with stage T1N0, T2N0, Grade I-II invasive ductal carcinoma received 9-10 Gy prescribed at 1 cm from the MammoSite balloon surface in two fractions of 4.5-5 Gy 6 h apart. The MammoSite was inserted 20-37 days postoperatively. External beam radiation therapy to the whole breast commenced 1-5 days after accelerated partial breast irradiation. The maximum skin dose ranged from 3 to 9 Gy. The skin-cavity distance ranged from 7 to 19 mm. Local discomfort resolved as the scar healed spontaneously within 3-5 days. No Grade III or higher acute toxicity or local infection was recorded. The ease of insertion and accuracy of dosimetry makes the MammoSite suitable for use in properly selected women with early-stage breast cancer in a trial setting.

Hyponatraemia as a risk factor for hospital mortality

Hyponatraemia is a common abnormality in hospitalized patients, with about 15% having levels below the lower limit of the laboratory reference range. Accepted wisdom is that hyponatraemia is a marker of poor prognosis. However, a critical analysis of the literature reveals significant problems. Researchers have used various cut-off levels for plasma sodium, often concentrating on more severely hyponatraemic groups. Many studies were small, and most did not include control groups. Nevertheless, the literature available does suggest an excess mortality associated with hyponatraemia. Whether this is a direct adverse effect of low serum sodium levels, or if hyponatraemia is simply a marker for 'sicker' patients, is not known. It is also uncertain whether mortality is increased with more severe hyponatraemia, or whether active correction of hyponatraemia will improve outcome. These issues should be addressed by adequately-powered, prospective, suitably controlled studies.

Investigation and management of severe hyponatraemia in a hospital setting

AIMS

To evaluate the assessment and management of severe hyponatraemia in a large teaching hospital.

METHODS

Inpatients with serum sodium <125 mmol/l were identified prospectively from a laboratory database over a six month period. Notes were examined and data extracted. Case notes were carefully reviewed retrospectively by a consultant endocrinologist with regard to accuracy of the diagnosis and the appropriateness of investigations and management.

RESULTS

104 patients with a serum sodium <125 mmol/l were identified. Mean (SD) age was 69 (14), 52% were female, mean hospital stay was 16 (12) days, and overall mortality 27%. Adequate investigations were rarely performed. Only 28 (26%) had plasma osmolality measured, 29 (27%) urine osmolality, 11 (10%) urinary sodium, 8 (8%) plasma cortisol, and 2 (2%) a short Synacthen test. Comparing the "ward" and "specialist review" diagnoses, there were significant discrepancies for "no cause found" (49% v 27%, p<0.001), alcohol (6% v 11% p<0.01), and syndrome of inappropriate antidiuresis (20% v 32%, p = 0.001). Treatment was often illogical with significant management errors in 33%. These included fluid restriction and intravenous saline given together (4%) and fluid restriction in diuretic induced hyponatraemia (6%). Mortality was higher in the group with management errors (41% v 20% p = 0.002).

CONCLUSION

Severe hyponatraemia is a serious condition, but its investigation and evaluation is often inadequate. Some treatment patterns seem to be arbitrary and illogical, and are associated with higher mortality.

Successful cardiovascular risk reduction in Type 2 diabetes by nurse-led care using an open clinical algorithm

AIM

To implement a protocol-driven, nurse-led cardiovascular risk reduction clinic using an open clinical algorithm. The primary aim of the clinic was to optimize blood pressure (BP) control; secondary aims were to reduce modifiable cardiovascular risk factors.

METHODS

We studied 110 people with Type 2 diabetes attending a diabetes out-patient centre at University Hospital Aintree, Liverpool. Patients taking one or more antihypertensive drugs were selected for referral to the nurse-led clinic if BP was > 140/85 mmHg; there was no age threshold. An open clinical algorithm was designed to direct the nurse on the use of antihypertensive, statin and aspirin therapy plus lifestyle advice and concordance.

RESULTS

Thirty-one percent of patients attending for a first visit to the nurse-led clinic had BP within target when measured to British Hypertension Society standards out of the consultant clinic. Mean BP was 150/76 mmHg compared with 178/88 mmHg (P < 0.001). Subsequently, BP was reduced to 130/68 mmHg (P < 0.001), this reduction being sustained at review 9 months later (mean BP 133/67 mmHg), with 87 (79%) achieving BP <or= 140/85 mmHg. Treatment modalities were adjusted to reduce cardiovascular risk, including antihypertensive medication, lipid-lowering therapy and antiplatelet therapy. High-density lipoprotein-cholesterol improved from 1.2 +/- 0.5 mmol/l to 1.4 +/- 0.5 mmol/l (P = 0.004). The number of patients with microalbuminuria decreased from 41 (47%) to 25 (28%) (P = 0.02), with a fall in urinary albumin:creatinine ratio from 3.0 (1.3-7.9) to 1.8 (1.0-5.0) mg/mmol (P = 0.01). The number of smokers decreased from 22 (20%) to 14 (13%) (P = 0.01). Although not included as an intervention in the protocol, HbA1c improved to 8.1 +/- 1.6% from 8.7 +/- 1.6% (P < 0.001).

CONCLUSION

A protocol-driven, nurse-led clinic using an open clinical algorithm can be used effectively to manage cardiovascular risk reduction in Type 2 diabetes.

Uteroplacental insufficiency affects epigenetic determinants of chromatin structure in brains of neonatal and juvenile IUGR rats

Intrauterine growth retardation (IUGR) increases the risk of neuroendocrine reprogramming. In the rat, IUGR leads to persistent changes in cerebral mRNA levels. This suggests lasting alterations in IUGR cerebral transcriptional regulation, which may result from changes in chromatin structure. Candidate nutritional triggers for these changes include altered cerebral zinc and one-carbon metabolite levels. We hypothesized that IUGR affects cerebral chromatin structure in neonatal and postnatal rat brains. Rats were rendered IUGR by bilateral uterine artery ligation; controls (Con) underwent sham surgery. At day of life 0 (d0), we measured cerebral DNA methylation, histone acetylation, expression of chromatin-affecting enzymes, and cerebral levels of one-carbon metabolites and zinc. At day of life 21 (d21), we measured cerebral DNA methylation and histone acetylation, as well as the caloric content of Con and IUGR rat breast milk. At d0, IUGR significantly decreased genome-wide and CpG island methylation, as well as increased histone 3 lysine 9 (H3/K9) and histone 3 lysine 14 (H3/K14) acetylation in the hippocampus and periventricular white matter, respectively. IUGR also decreased expression of the chromatin-affecting enzymes DNA methyltransferase 1 (DNMT1), methyl-CpG binding protein 2 (MeCP2), and histone deacetylase (HDAC)1 in association with increased cerebral levels of zinc. In d21 female IUGR rats, cerebral CpG DNA methylation remained lower, whereas H3/K9 and H3/K14 hyperacetylation persisted in hippocampus and white matter, respectively. In d21 male rats, IUGR decreased acetylation of H3/K9 and H3/K14 in these respective regions compared with controls. Despite these differences, caloric, fat, and protein content were similar in breast milk from Con and IUGR dams. We conclude that IUGR results in postnatal changes in cerebral chromatin structure and that these changes are sex specific.

Improved glycaemic control--an unintended benefit of a nurse-led cardiovascular risk reduction clinic

AIMS

One hundred and ten patients with Type 2 diabetes were referred into a nurse-led cardiovascular risk reduction clinic. The primary aim of the clinic was to optimize blood pressure (BP) control and address cardiovascular risk factors.

METHODS

Those attending outpatient clinics were referred into a nurse-led cardiovascular risk reduction clinic if BP was above 140/85 mmHg. There was no intervention strategy designed in the nurse clinic protocol to improve glycaemic control.

RESULTS

Following attendance at the clinic, there was a significant improvement in HbA1c noted when patients were reviewed 9 months later. HbA1c improved from 8.7 +/- 1.6 to 8.1% +/- 1.6% (P < 0.001) in the whole cohort. Further analysis showed that, after excluding those who had received intervention to improve glycaemic control from another source, during the same period there remained a significant improvement in the non-intervention group of patients.

CONCLUSION

Frequent regular contact and health education in a nurse-led clinic to reduce cardiovascular risk may improve HbA1c in the absence of any specific intervention to improve glycaemic control.

Effect of a barley breakfast cereal on blood glucose and insulin response in normal and diabetic patients

Prowashonupana (Prowash) is a shrunken-endosperm, short awn, waxy starch, hulless barley with low starch, high fiber, high protein, and a relatively high concentration of free sugars. The study was designed to compare equivalent breakfast meals (w/w) of Prowash and oatmeal for glycemic response in diabetic and non-diabetic subjects. A commercial liquid meal replacer (LMR) was included as a reference standard. A substantial reduction of the post-prandial glycemic peak following ingestion of Prowash was observed as compared to LMR or oatmeal. In the non-diabetic subjects, the maximal rise in glucose from baseline was 26.3 +/- 3.9 mg/dL after LMR, 41.3 +/- 3.9 mg/dL after oatmeal and 6.4 +/- 2.7 mg/dL after Prowash (p < 0.01). The maximal increase in glucose in the diabetic patients was 69.9 +/- 4.5 mg/dL after LMR, 80.8 +/- 8.8 mg/dL after oatmeal and 28.4 +/- 3.5 mg/dL after Prowash (p < 0.01). The maximal increase in insulin post-LMR was 33.9 +/- 3.6 mIU/ml in the diabetic patients and 54.0 +/- 9.8 mIU/ml in the non-diabetic controls. Oatmeal elicited a maximal insulin increase of 29.9 +/- 4.2 mIU/ml in the control subjects and 21.4 +/- 2.5 mIU/ml in the diabetic patients. In contrast, the maximal insulin increase after Prowash was 8.6 +/- 1.5 mIU/ml in the non-diabetic controls and 6.8 +/- 1.2 mIU/ml in the diabetic patients (p < 0.01).

On the role of the starved codon and the takeoff site in ribosome bypassing in Escherichia coli

Translating ribosomes can skip over stretches of messenger RNA and resume protein chain elongation after a "bypassed" region. We have previously shown that limitation for isoleucyl-tRNA can initiate a ribosome bypass when an AUA codon is in the ribosomal A-site. We have now generalized this effect to other "hungry" codons calling for four different limiting aminoacyl-tRNA species, suggesting that a pause at any A-site will have this effect. We have assessed bypassing in a large family of reporters with nearly every different triplet in the "takeoff site", i.e. the P-site on the 5' side of the hungry codon, and an identical "landing site" codon 16 nucleotides downstream. The different takeoff sites vary over a factor of 50 in bypassing proficiency. At least part of this variation appears to reflect stability of the codon Colon, two colons anticodon interaction at the takeoff site, as indicated by the following: (a) the bypassing proficiency of different tRNAs shows a rough correlation with the frequency of A Colon, two colons U as opposed to G Colon, two colons C pairs in the codon Colon, two colons anticodon association; (b) specific tRNAs bypass more frequently from codons ending in U than from their synonym ending in C; (c) an arginine tRNA with Inosine in the wobble position which reads CGU, CGC, and CGA bypasses much more frequently from the last codon than the first two synonyms.