Slowly fading super-luminous supernovae that are not pair-instability explosions.

Super-luminous supernovae that radiate more than 10(44) ergs per second at their peak luminosity have recently been discovered in faint galaxies at redshifts of 0.1-4. Some evolve slowly, resembling models of 'pair-instability' supernovae. Such models involve stars with original masses 140-260 times that of the Sun that now have carbon-oxygen cores of 65-130 solar masses. In these stars, the photons that prevent gravitational collapse are converted to electron-positron pairs, causing rapid contraction and thermonuclear explosions. Many solar masses of (56)Ni are synthesized; this isotope decays to (56)Fe via (56)Co, powering bright light curves. Such massive progenitors are expected to have formed from metal-poor gas in the early Universe. Recently, supernova 2007bi in a galaxy at redshift 0.127 (about 12 billion years after the Big Bang) with a metallicity one-third that of the Sun was observed to look like a fading pair-instability supernova. Here we report observations of two slow-to-fade super-luminous supernovae that show relatively fast rise times and blue colours, which are incompatible with pair-instability models. Their late-time light-curve and spectral similarities to supernova 2007bi call the nature of that event into question. Our early spectra closely resemble typical fast-declining super-luminous supernovae, which are not powered by radioactivity. Modelling our observations with 10-16 solar masses of magnetar-energized ejecta demonstrates the possibility of a common explosion mechanism. The lack of unambiguous nearby pair-instability events suggests that their local rate of occurrence is less than 6 × 10(-6) times that of the core-collapse rate.

A dust-enshrouded tidal disruption event with a resolved radio jet in a galaxy merger.

Tidal disruption events (TDEs) are transient flares produced when a star is ripped apart by the gravitational field of a supermassive black hole (SMBH). We have observed a transient source in the western nucleus of the merging galaxy pair Arp 299 that radiated >1.5 × 1052 erg at infrared and radio wavelengths but was not luminous at optical or x-ray wavelengths. We interpret this as a TDE with much of its emission reradiated at infrared wavelengths by dust. Efficient reprocessing by dense gas and dust may explain the difference between theoretical predictions and observed luminosities of TDEs. The radio observations resolve an expanding and decelerating jet, probing the jet formation and evolution around a SMBH.

Nationwide survey of comorbidity, use, and costs of all medications in Finnish diabetic individuals.

OBJECTIVE: To investigate comorbidity and overall use and costs of medication for all Finnish individuals with diabetes treated with drugs compared with sex- and age-matched control subjects. RESEARCH DESIGN AND METHODS: According to a cross-sectional population study using national registries, 116,224 individuals purchased antidiabetic medications in Finland in 1995. The same number of nondiabetic individuals matched for sex, age, and area of residence were chosen as control subjects. Age at onset of diabetes was used as a criterion for distinguishing between type 1 and type 2 diabetes. The criterion could be applied in 74% of cases. A total of 16,955 individuals were defined as having type 1 diabetes, and 68,517 were defined as having type 2 diabetes. Comorbidity was determined by linkage with a national register including all individuals entitled to special reimbursement for drug treatment for a range of chronic diseases. Data on use and costs of all medications prescribed were obtained from drug purchase records. RESULTS: Cardiovascular diseases and uremia were, as expected, the chronic diseases most closely associated with diabetes. Use of almost all kinds of medication was significantly greater in individuals with type 1 and type 2 diabetes than in control subjects. The greatest differences were observed in relation to cardiovascular drugs and antibiotics. Unexpectedly low use of antiasthmatics was observed in individuals with both types of diabetes, low use of neuroleptics was observed in type 1 diabetic individuals, and low use of hormone replacement therapy was observed in women with type 2 diabetes. Total costs of medications for individuals with diabetes were 3.5 times greater than those for nondiabetic control subjects. The higher costs were mostly attributable to insulin therapy for individuals with type 1 diabetes. The higher costs for individuals with type 2 diabetes were related to the cost of medications other than antidiabetic medication. The possible selection bias in omitting diabetic individuals treated with diet only and individuals in whom diabetes type could not be determined must be considered in interpreting the results. CONCLUSIONS: Greater use by and costs of medications for individuals with diabetes than for nondiabetic individuals is related not only to antidiabetic treatment but also to all other kinds of medications. Although drug treatment and the prevalence of several chronic conditions were overall greater in individuals with diabetes versus other individuals, some exceptions merit further study

Hospital use among diabetic patients and the general population.

OBJECTIVE: This register-based linkage study compared hospital use among diabetic and nondiabetic populations. The study focused on overall use, use by disease categories, and inpatient care caused by complications. RESEARCH DESIGN AND METHODS: The patient data were derived from the Hospital Discharge Register and the Central Drug Register in Finland. All drug-treated diabetic patients and discharges of patients in a 3-year period were included in the study. Hospital use was measured by inpatient days, mean length of stay, and discharge rate. RESULTS: Among diabetic patients were eligible for drug reimbursement, 14.2% had at least one hospital stay because of diabetes in a year, while 50.7% had at least one hospital stay for any cause. Only 12.4% of the nondiabetic population was hospitalized annually. Patients with diabetes as the principal diagnosis consumed about 3% of all inpatient days; patients who had diabetes either as the principal or as a subsidiary diagnosis used 8.3%; and people who were eligible for antidiabetic drug reimbursement used 13.3% of total inpatient days. Among diabetic children, the risk for hospitalization was 6.5 times higher than among nondiabetic children. With advancing age, causes other than diabetes increasingly dominated hospitalization among diabetic patients. Inpatient days because of cardiovascular diseases were 1.6-18 times more common among diabetic patients than among nondiabetic patients, depending on gender and age-group. Diabetic patients used many more hospital inpatient days than did the nondiabetic population for a number of other disease categories that are usually not related to diabetes. CONCLUSIONS: Hospital use among diabetic patients is substantially greater than that among the nondiabetic population, mainly because of cardiovascular and microvascular complications, but also because of diseases unrelated to diabetes.

Glycemic control in patients with diabetes in Finland.

OBJECTIVE: To evaluate the quality of diabetes care at a national level in Finland, using level of glycemia as a determinant of success in treatment. RESEARCH DESIGN AND METHODS: Physicians and diabetes nurses in 76 randomly selected clinics (59 primary care units and 17 hospitals) evenly covering the whole of Finland were asked to fill in a questionnaire asking for data based on the 1993 medical records of a random sample of 50 diabetic patients from each center (total n = 3,800). HbAlc was used as an index of glycemic control. RESULTS: Information on 3,195 (84%) diabetic patients was received. HbAlc was measured in 67% of the patients in 1993. The mean HbAlc in the whole population was 8.6 +/- 1.9% (normal range 4-6%). Some 25% of patients had HbAlc < or = 7.3%, while 25% had HbAlc > or = 9.7%. The mean HbAlc was 8.8 +/- 1.9% in type 1 and 8.5 +/- 1.9% in type 2 diabetic patients. There was no sex difference in the HbAlc level in type 1 diabetic patients. However, male type 2 diabetic patients had better glycemic control than female patients (8.3 +/- 1.9 vs. 8.8 +/- 1.9%, P < 0.0001). The sex difference was independent of the type of therapy. The mean level of glycemic control was lowest among individuals with the shortest duration of diabetes. After 7-9 years after the diagnosis, there was no change in the mean level of glycemia. CONCLUSIONS: Average glycemic control is poor in a majority of the diabetic patients in Finland. Better treatment strategies and methods should be used to improve glycemic control and to reduce long-term complications.

Structure and costs of health care of diabetic patients in Finland.

OBJECTIVE: The aim of the present study was to examine both the structure, including modes of drug treatment, ambulatory care, and hospital inpatient care, and the costs of health care for drug-treated diabetic patients in Finland. RESEARCH DESIGN AND METHODS: The modes of drug treatment and ambulatory care were studied with the help of a questionnaire given to all diabetic patients obtaining their medication through pharmacies in Finland during a 7-week period in 1989. The questionnaire sought information on drug treatment, site of health care, and frequency of visits to physicians. Hospital inpatient care was evaluated by linking the patient data from the Hospital Discharge Register and the Central Drug Register. The direct costs of health care were calculated by using relevant average costs. RESULTS: A total of 30,266 questionnaires were returned, representing > 70% of all drug-treated diabetic patients receiving medication in the period studied. Of the diabetic patients, 63% were treated by oral medication only, 31% by insulin only, and 6% by a combination of insulin and oral agents. Of the patients in whom diabetes was diagnosed at > or = 30 years of age, 75% were treated at health centers, whereas > 60% of those in whom diabetes was diagnosed at < 30 years of age were treated at outpatient clinics. The mean annual frequency of visits was 4.0 for patients receiving insulin treatment and 3.3 for patients receiving treatment with oral medications. The diabetic patients used 1.5 million hospital inpatient days per year, which was 13% of the total inpatient days in Finland. Of the inpatient days, 20% were for diabetes as the principal cause, 52% for diabetes-related diseases, and 28% for causes unrelated to diabetes. The direct costs of the health care of drug-treated diabetic patients in 1989 were 5.8% of the total costs of health care in Finland and were three times higher than the average costs of care for nondiabetic individuals. The direct costs were divided into inpatient care (81%), medication (9%), ambulatory care (8%), and self-care equipment (2%). CONCLUSIONS: Hospital inpatient care is the major contributor to the excess of health care expenditures for diabetic patients.

Loss of stromal glycosaminoglycans during corneal edema.

This study tried to determine if glycosaminoglycans (GAGs) are released from the rabbit stroma during corneal edema. The GAGs of rabbit corneas were labeled in situ using anterior-chamber injections of 35S-sulfate and 3H-glucosamine. Labeled corneal pairs were excised and the endothelium perfused in vitro in the specular microscope. Edema was induced in one cornea by perfusion with a calcium-free balanced salt solution; the control cornea was perfused with glutathione bicarbonate Ringer's (GBR). Corneal thickness was measured every 15 minutes during the 3-hour perfusion period, and perfusate fractions were collected from each cornea and analyzed for the presence of GAGs. Edematous corneas swelled from 438 +/- 14.8 microns to 688 +/- 10.6 microns compared with control corneas (427 +/- 4.7 microns to 454 +/- 7.2 microns). Total 3H-glucosamine (4.00 +/- 0.68%) and 35S-sulfate (10.36 +/- 0.92%) released from the edematous corneas during perfusion exceeded that lost by control corneas (1.92 +/- 0.18% for 3H-glucosamine; 3.23 +/- 0.52% for 35S-sulfate). Enzymatic digestion studies showed the presence of keratan sulfate in the edematous perfusates. The results suggest that increased loss of radiolabeled components from edematous corneas represent a loss of stromal GAGs and possibly GAG fragments. Therefore, corneal edema involves loss of GAGs and water uptake.

Endophthalmitis after filtering surgery with mitomycin.

OBJECTIVE: To identify the incidence, causative organisms, and clinical outcomes of eyes with bleb-associated endophthalmitis after glaucoma filtering procedures with adjunctive mitomycin. METHODS: Retrospective analysis of 773 consecutive eyes that underwent glaucoma filtering surgery at the Bascom Palmer Eye Institute, Miami, Fla. The course of 609 eyes from 485 patients with a minimum of 3 months of follow-up were reviewed. RESULTS: Mean follow-up was 16.0 +/- 11.5 months (range, 3-48 months). Of the 609 eyes, 13 (2.1%) developed bleb-associated endophthalmitis an average of 18.5 +/- 13.2 months after surgery (range, 1-45 months). The incidence of bleb-associated endophthalmitis was significantly greater after inferior trabeculectomy (7.8% per patient-year) than after superior trabeculectomy (1.3% per patient-year) by Kaplan-Meier estimates (P = .02, log rank test). The cumulative incidence was 13% for inferior limbal blebs and 1.6% for superior limbal blebs. Nine (69.2%) of the 13 eyes were culture positive. Streptococcus sanguis and Haemophilus influenzae (6/13 [46.2%]) were the most frequent causative organisms. The mean increase in intraocular pressure after endophthalmitis treatment was 1.2 mm Hg, with a mean decrease in visual acuity of 1.42 logMAR units. Eight (61.5%) of the 13 eyes had a final acuity of 20/400 or better. CONCLUSIONS: The incidence of bleb-associated endophthalmitis after guarded filtering surgery performed with adjunctive mitomycin is higher than the reported rate in eyes undergoing filtering surgery without the use of antifibrotic agents (0.2%-1.5%). Inferior limbal trabeculectomy carries the highest risk of infection. Eyes with mitomycin blebs maintained excellent filtration capacity. However, after treatment of the infection, the visual outcomes were generally poor.

Reversible loss of light perception after vitreoretinal surgery.

PURPOSE: We studied reversible loss of light perception after vitreoretinal surgery to show that functional vision can return in some patients. METHODS: We reviewed the medical records of seven patients who had postoperative reversible loss of light perception in the eye that underwent vitreoretinal surgery. Differences in the postoperative courses and interventions were studied. RESULTS: Five of the seven patients had diabetes mellitus but none had hypertension. The indications for vitreoretinal surgery were severe proliferative diabetic retinopathy in five patients and retinal detachment with advanced proliferative vitreoretinopathy in two patients. Seven patients had reversible loss of light perception within the first three postoperative days. Six of the seven patients had an intraocular pressure greater than 26 mm Hg at the time the eye had no light perception. Decreasing the intraocular pressure was associated with return of light perception in five of seven patients. Return of useful vision was gradual. Four of seven patients had a visual acuity of 20/400 or better one month after surgery, and all seven had a visual acuity of 20/400 or better three months after surgery. Visual acuity in four eyes improved further to 20/70 or better at six months or more after surgery. CONCLUSION: Reversible loss of light perception after vitreoretinal surgery does occur in some patients. Monitoring vision and intraocular pressure is important because prompt treatment may assist in the recovery of functional vision.

Comparison of corneal preservation media for corneal hydration and stromal proteoglycan loss.

Changes in the composition of stromal proteoglycans (PGs) have been previously demonstrated in corneal edema, wound healing, and disease. To examine if PGs are lost during corneal preservation, rabbit corneal PGs were radiolabeled in situ with 35S-sulfate and 3H-glucosamine, excised and stored in either modified McCarey-Kaufman medium (MMK), K-Sol (Coopervision-Cilco, Bellevue, WA, U.S.A.), corneal storage medium (CSM), or Dexsol (Chiron Ophthalmics, Irvine, CA, U.S.A.) for up to 14 days. The percentage of total radio-label lost was significantly greater from de-epithelialized corneas (p less than 0.05) and from corneas stored in CSM (p less than 0.05) or K-Sol (p less than 0.05). Corneas stored in CSM for 4 and 7 days were significantly more hydrated than corneas stored in MMK, K-Sol, or Dexsol. After 14 days of storage, all corneas were hydrated above control values with the Dexsol-stored cornea showing the least hydration. Results suggest that loss of stromal PGs during corneal storage is reduced with epithelial integrity and with preservation media containing dextran.

Premedication for outpatient adenoidectomy: comparison between ketamine and pethidine.

A comparison of intramuscular ketamine and pethidine as premedicants was carried out in a series of 32 children under two years of age who were given thiopentone-N2O-O2-succinyl choline anesthesia for elective outpatient adenoidectomy. Fourteen (87.5%) of the 16 children premedicated with ketamine (3 mg./kg.) were calm or asleep when brought into the operating room as compared to 4 (25.0%) of the 16 children (p less than 0.001) premedicated with pethidine (1 mg/kg.). Immediate recovery was similar in the groups premedicated with ketamine and pethidine. These two small groups of children did not differ significantly in their emotional state during recovery room observation, nor during the 48 postoperative hours at home, either. It is suggested that ketamine administered intramuscularly is a suitable agent for outpatient premedication of small children because of its rapid action, excellent sedative and analgesic properties and low incidence of side-effects.