Systematic screening for diabetic retinopathy with a digital fundus camera following pupillary dilatation in a university diabetes department.

AIMS: Screening for diabetic retinopathy (DR) is highly inadequate in France because of insufficient infrastructure and increasing disease prevalence. We describe the results of the first systematic DR screening programme established in a university diabetes department. METHODS: In this cross-sectional study conducted over 1 year, consecutive adult patients underwent three-field retinal photography with the Topcon TRC NW6S digital fundus camera following pupillary dilatation with Tropicamide 1%. A questionnaire provided information on patients' systemic and ocular history. Glycated haemoglobin (HbA1c) was measured at the screening visit.Two ophthalmologists graded the retinal photographs in a masked fashion. RESULTS: Of 1157 patients attending the diabetes department, 1153 (99.7%)underwent photographic screening. Images were gradable in 96% patients.Diabetic retinopathy was detected in 522 (45%) patients and sight-threatening DR in 167 (14%). Of 704 (61%) patients previously believed to have no DR,254 (34%) screened positive. The presence of DR was associated with age,insulin use and non-Caucasian ethnicity in Type 2 patients, and with duration of diabetes and HbA1c in Type 1 and Type 2 patients. Associated ocular pathologies were diagnosed in 612 (53%) patients. CONCLUSIONS: Our photographic screening programme using pharmacological mydriasis provided a high screening coverage feasible in a hospital setting. We obtained information regarding prevalence and associated risk factors of DR inpatients attending a tertiary care centre. Screening was well accepted by patients and met with no protest from city ophthalmologists. It generated considerable interest among endocrinologists and feedback of results is expected to improve optimization of glycaemic control.     

Dual mechanisms of regulation of type I iodothyronine 5''-deiodinase in the rat kidney, liver, and thyroid gland. Implications for the treatment of hyperthyroidism with radiographic contrast agents.

Alterations in thyroid hormone status and the administration of radiographic contrast agents can markedly influence iodothyronine metabolism and, in particular, the activity of type I 5'-deiodinase (5'DI). In the present studies, the mechanisms responsible for these effects have been reassessed. As previously reported, the addition of iopanoic acid (IOP) to broken cell preparations resulted in a competitive pattern of 5'DI inhibition. However, the in vivo administration to rats of IOP or 3,3',5'-triiodothyronine (rT3) resulted in a noncompetitive pattern of inhibition of 5'DI in the liver, kidney, and thyroid gland, whereby marked decreases in maximal enzyme velocity (V max) were noted, with no change in the value of the Michaelis-Menten constant. In rats rendered hyperthyroid by the injection of 3,5,3'-triiodothyronine (T3), 5'DI activity was significantly increased in the liver and the kidney. The administration of IOP to these thyrotoxic animals resulted in a rapid loss of enzyme activity characterized by an approximate 80% decrease in 5'DI V max values in both tissues. Furthermore, this inhibitory effect persisted for longer than 60 h after a single IOP injection. IOP administration also decreased 5'DI V max levels in the thyroid gland by 52%. In other experiments, treatment of intact Reuber FAO hepatoma cells with IOP or rT3 induced a rapid decrease in 5'DI V max levels. In cells treated with cycloheximide, these agents enhanced the rate of disappearance of enzyme activity by greater than 12-fold, indicating a predominant effect on accelerating the rate of enzyme inactivation and/or degradation. These studies demonstrate that iodothyronines and other iodinated compounds have complex regulatory effects on 5'DI that entail alterations in the rates of both enzyme activation and inactivation. The previously accepted concept that rT3 and IOP impair thyroxine (T4) to T3 conversion in vivo by acting as competitive inhibitors is an oversimplification. Rather, the clinically beneficial effects of administering these agents to patients with hyperthyroidism may result primarily from the rapid and prolonged inactivation of 5'DI which occurs in the thyroid gland and peripheral tissues.     

Vascular problems in gastric esophagoplasty after esophagectomy or circular pharyngolaryngectomy

Gastric oesophagoplasty (GOP) after total oesophagectomy or circular pharyngolaryngectomy is complicated by an average anastomotic breakdown or fistula rate of 15%, and a stenosis rate of 8%. Ischemia related to the actual procedure itself undoubtedly plays a role in the production of such complications in spite of the rich vascular supply to the stomach. The authors report the results of an anatomical study involving 24 stomachs from non-embalmed adults studied by various forms of arteriography depending in the GOP technique employed. For healthy normotensive gastric arteries, they demonstrate the principal elements likely to influence the vascularisation of the graft and propose a provisional vascular score for ischemia. Based on this, they discuss the vascular risks associated with GOP techniques in general.     

Enhanced Fluid Removal Guided by Blood Volume Monitoring During Chronic Hemodialysis

Fluid overload predisposes chronic hemodialysis patients to cardiovascular disease, a significant cause of morbidity and mortality in these patients. We evaluated the efficacy of monitoring changes in blood volume during routine hemodialysis to detect fluid overload. Intradialytic changes in blood volume were monitored by continuously measuring hematocrit in all 56 patients in a single dialysis unit over 7 weeks. After Week 1, patients were categorized into 2 separate groups depending on their maximum intradialytic decreases in blood volume. In Group 1, 46 of 56 or 82% had greater than a 5% decrease in blood volume while in Group 2, 10 of 56 or 18% had less than a 5% decrease in blood volume. During Weeks 2–7, dialytic fluid removal was intentionally increased in Group 2 patients by 0.80 ± 0.62 L (mean ± SD) or 47 ± 43%. This intervention resulted in a larger (p < 0.02) intradialytic decrease in body weight (2.7 ± 0.9 kg versus 2.0 ± 0.8 kg) and a larger (p < 0.02) intradialytic decrease in blood volume (15 ± 5% versus 4 ± 1%) than experienced during Week 1 with a low incidence of symptoms. We conclude that there is a significant percentage of chronic hemodialysis patients who can tolerate additional fluid removal without hypovolemic symptoms even though they are considered to be at dry weight by routine physical examination and that the identification of these patients can be facilitated by intradialytic blood volume monitoring.     

Effect of zidovudine resistance mutations on virologic response to treatment with zidovudine or stavudine,each in combination with lamivudine and indinavir

The authors studied the effect of zidovudine (ZDV) resistance mutation on virologic response to treatment with ZDV or stavudine (d4T) each in combination with lamivudine and indinavir. Viral genotyping was performed on plasma HIV-1 RNA at study entry and concerned 155 patients previously treated with ZDV, didanosine, or zalcitabine and enrolled in the NOVAVIR (Agence National de Recherche sur le SIDA [ANRS] 073) trial. Three virologic responses were investigated: early response (<50 copies/mL at week 24), late response (<500 copies/mL at week 80), and virologic failure (two HIV-1 RNA >5000 copies/mL). Patients were classified as resistant or susceptible to ZDV according to the ANRS algorithm. Plasma viral RNA from 123 of 155 patients had two or more ZDV resistance mutations. The number of ZDV resistance mutations was positively correlated with the duration of prior antiviral therapy (p <.001). At week 24, 74% and 77% of patients with virus classified as resistant were responders in the d4T and ZDV arm, respectively. Similar results were found at week 80. Virologic failure was reached in 7 of 24 patients with virus classified as susceptible and in 26 of 131 patients with resistant virus (p =.29). In the ZDV arm, patients classified as resistant had longer times to virologic failure than those classified as susceptible (p =.003). In conclusion, sustained virologic response despite presence of ZDV resistance mutations implies that these mutations do not preclude an early and durable response to treatment with a potent three-drug regimen in these patients. Patients susceptible to ZDV had lower median mean corpuscular volumes and lower random indinavir levels, suggesting that adherence was the main reason for failure.     

Building research administration applications for the academic health center: a case study.

The academic health center information environment is saturated with information of varying quality and overwhelming quantity. The most significant challenge is transforming data and information into knowledge. The University of Cincinnati Medical Center's (UCMC) focus is to develop an information architecture comprising data structures, Web services, and user interfaces that enable individuals to manage the information overload so that they can create new knowledge. UCMC has accomplished much of what is reported in this article with the help of a four-year Integrated Advanced Information Management Systems (IAIMS) operation grant awarded by the National Library of Medicine in 2003. In the UCMC vision for knowledge management, individuals have reliable, secure access to information that is filtered, organized, and highly relevant for specific tasks and personal needs. Current applications and tool sets will evolve to become the next generation knowledge management applications or smart digital services. When smart digital services are implemented, silo applications will disappear. A major focus of UCMC's IAIMS grant is research administration. Testing and building out existing and new research administration applications and digital services is underway. The authors review UCMC's progress and results in developing a software architecture, tools, and services for research administration. Included are sections on the evolution to full integration, the impact of the work at UCMC to date, lessons learned during this research and development process, and future plans and needs.