Oculomotor tracking in two dimensions

Results from studies of oculomotor tracking in one dimension have indicated that saccades are driven primarily by errors in position, whereas smooth pursuit movements are driven primarily by errors in velocity. To test whether this result generalizes to two-dimensional tracking, we asked subjects to track a target that moved initially in a straight line then changed direction. We found that the general premise does indeed hold true; however, the study of oculomotor tracking in two dimensions provides additional insight. The first saccade was directed slightly in advance of target location at saccade onset. Thus its direction was related primarily to angular positional error. The direction of the smooth pursuit movement after the saccade was related linearly to the direction of target motion with an average slope of 0.8. Furthermore the magnitude and direction of smooth pursuit velocity did not change abruptly; consequently the direction of smooth pursuit appeared to rotate smoothly over time.

Safety of insulin lispro: pooled data from clinical trials

The safety of insulin lispro was compared with that of regular human insulin of recombinant DNA origin (Humulin R, Lilly), with special emphasis on the development and progression of the chronic complications of diabetes mellitus in relation to insulin therapy. Ten clinical trials of 3634 patients with type 1 and type 2 diabetes mellitus were analyzed. The primary focus was treatment-emergent adverse events, and the secondary focus was the development and progression of the chronic complications of diabetes. The evaluations were based on pertinent laboratory values, predetermined disease-specific COSTART (coding symbol and thesaurus for adverse event terminology) terms, physician evaluations of patients, and physical examinations. There were no clinically or statistically significant differences in the frequency of treatment-emergent adverse events or progression of retinopathy, neuropathy, or cardiovascular disease reported with each therapy. There was no difference between insulin lispro and Humulin R in the occurrence and progression of kidney disease as measured by changes in serum creatinine levels. Pooled data from clinical studies show that insulin lispro has a safety profile comparable to that of Humulin R.

Improved postprandial blood glucose control and reduced nocturnal hypoglycemia during treatment with two novel insulin lispro-protamine formulations, insulin lispro mix25 and insulin lispro mix50. Mix50 Study Group

The objective of this 6-month, open-label, randomized, two-period crossover study was to compare glycemic control when patients were treated with (1) 2 manufactured premixed insulin formulations containing insulin lispro and a novel insulin lispro-protamine formulation, neutral protamine lispro (NPL), and (2) 2 manufactured premixed human insulin formulations, human insulin 50/50 and human insulin 30/70. One hundred individuals, 37 with type 1 diabetes mellitus (12 females, 25 males; mean age, 39.4 years; mean body mass index [BMI], 24.8; mean duration of diabetes, 12.9 years) and 63 with type 2 diabetes mellitus (33 females, 30 males; mean age, 59.0 years; mean BMI, 28.4; mean duration of diabetes, 12.6 years), were treated with insulin lispro mixtures. Insulin lispro Mix50 (50% insulin lispro/50% NPL) and human insulin 50/50 (50% regular insulin/50% neutral protamine Hagedorn [NPH] insulin) were administered before breakfast; insulin lispro Mix25 (25% insulin lispro/75% NPL) and human insulin 30/70 (30% regular insulin/70% NPH) were administered before dinner. Blood glucose (BG), hypoglycemic episodes (hypoglycemic signs or symptoms or BG <3.0 mmol/L), insulin dose and timing of dose before meals, and hemoglobin A1c were measured. Mean doses of insulin lispro and human insulin mixtures were similar overall and for both diabetes subgroups. However, compared with human insulin mixtures, twice-daily administration of insulin lispro mixtures resulted in improved postprandial glycemic control, similar overall glycemic control, and less nocturnal hypoglycemia, as well as offering the convenience of dosing closer to meals.

Identification of patients likely to benefit from biofeedback for outlet obstruction constipation

BACKGROUND

Biofeedback for outlet obstruction constipation has a varying success rate. The aim of this study was to identify which patients are likely to respond to biofeedback.

METHODS

Thirty patients with severe outlet obstruction constipation were treated by a specialist nurse using three or four sessions of visual and auditory feedback of anal sphincter pressures. All patients were assessed by evacuating proctography, whole-gut transit studies and anorectal physiology before treatment.

RESULTS

Two patients did not complete the course of biofeedback. Nine patients improved. Before treatment these patients had predominantly normal anorectal physiology and were all able to open the anorectal angle at evacuating proctography. Nineteen patients did not improve, of whom only three had no measured abnormality other than inability to empty the rectum. Ten of these patients had abnormal anorectal physiology which may have been due to previous vaginal delivery.

CONCLUSION

Biofeedback for outlet obstruction constipation is more likely to be successful in patients without evidence of severe pelvic floor damage.

Colonic motility is abnormal before surgery for rectal prolapse

BACKGROUND

Abdominal rectopexy remains the operation of choice for patients with rectal prolapse. Recurrence rates are low but the functional results are poor. Hindgut motility was measured before abdominal rectopexy to determine whether an underlying neuropathy might explain these poor results.

METHODS

Seven women of mean(s.d.) age 56(10) years had a multilumen catheter inserted in the colon before abdominal rectopexy. Colonic intraluminal pressure was recorded for a mean(s.d.) of 19(3) h; the number of peaks over 5 and 50 mmHg, motility and high-amplitude propagated contractions (HAPCs) were measured before and after a meal and compared with the findings in five controls.

RESULTS

Patients had high numbers of contractions greater than 5 mmHg and high motility before meals. Controls responded to meals by increasing motility, unlike patients. HAPCs were seen in one patient but in all controls.

CONCLUSION

These data show that patients with rectal prolapse have a hindgut motility abnormality before abdominal rectopexy, similar to that observed in spinal cord injury. This may explain the poor functional results after surgery, offering a rationale for colonic resection.

Meta-analysis of the effect of insulin lispro on severe hypoglycemia in patients with type 1 diabetes

OBJECTIVE

A precise time-action profile of insulin lispro (Humalog) at mealtime may reduce the incidence of severe hypoglycemia. Because it is a rare complication, we performed a cumulative meta-analysis to compare the frequency of severe hypoglycemia during insulin lispro and human regular insulin therapy in type 1 diabetic patients.

RESEARCH DESIGN AND METHODS

The analysis included eight large multi-center clinical trials, three with parallel and five with crossover designs. The studies included 2,576 type 1 diabetic patients in total, with 2,327 receiving insulin lispro and 2,339 receiving regular human insulin, representing > 1,400 patient-years of insulin therapy Severe hypoglycemia was defined as coma or requiring glucagon or intravenous glucose. The patients received either NPH or ultralente as their basal insulin and insulin lispro or regular human insulin before each meal.

RESULTS

Seventy-two patients (3.1%) had a total of 102 severe hypoglycemic episodes during insulin lispro therapy compared with 102 patients (4.4%) with a total of 131 episodes during regular human insulin therapy (P=0.024).

CONCLUSIONS

The results of this meta-analysis demonstrate that in type 1 diabetic patients, the frequency of severe hypoglycemia can be reduced by taking insulin lispro as compared with regular human insulin therapy.

A vascular catheterization simulator for training and treatment planning

We have developed a working prototype of an augmented reality based vascular catheterization simulator. The simulator is called daVinci, and provides the interventional radiologists with a "hands on, user friendly, image based environment to augment training, enhance pretreatment planning and design interventional products and devices. daVinci is based on computational modeling of human anatomical images and provides the user with capabilities for realtime simulated navigation of catheters in both 2-D and 3-D modeled vessels. In addition, multiplaner CT, MRI and anatomical data sets are incorporated into the simulator to enhance the understanding of anatomical relationships associated with vascular catheterization procedures. The current prototype is designed for peripheral vascular applications. Additional systems are currently being considered for both interventional neuroradiology and cardiology.

Effects of a short-acting insulin analog (Insulin Lispro) versus regular insulin on lipid metabolism in insulin-dependent diabetes mellitus

Insulin Lispro (IL) is a short-acting insulin analog that better reproduces the physiological postprandial insulin profile. The aim of this study was to compare the effects of intensive insulin therapy on lipid metabolism using preprandial IL and regular insulin (RI) in 10 insulin-dependent diabetes mellitus (IDDM) subjects. The mean hemoglobin A1c (HbA1c) at baseline was 7.13% +/- 1.2% and did not change after both treatments. In IDDM patients, total cholesterol and triglyceride levels appeared lower after RI than after IL. The low-density lipoprotein (LDL) to high-density lipoprotein (HDL) ratio significantly decreased only after RI (baseline, 2.01 +/- 0.6; IL, 1.88 +/- 0.6; RI, 1.71 +/- 0.5, P < .05). Although no very-low-density lipoprotein (VLDL) composition abnormalities were observed at baseline, the protein content was lower (P < .05) after IL (8.13% +/- 2.93%) than after RI (11.93% +/- 3.41%). Intermediate-density lipoprotein (IDL) protein depletion at baseline (6.14% +/- 6.84%) was normalized after both treatments (IL, 11.09% +/- 12.14%; RI, 10.38% +/- 16.68%, P < .05). LDL, HDL, HDL2, and HDL3 composition abnormalities were similar after both treatments and did not normalize. IDDM and control subjects showed similar LDL subfraction distribution at baseline and after both treatments. Two-hour postprandial VLDL composition alterations, although improved after RI, completely normalized after IL (P < .05). Lipoprotein lipase (LPL) and cholesteryl ester transfer protein (CETP) activities were similar to the control group and did not change after both treatments. Hepatic lipase (HL) activity was lower in diabetic patients (39.6 +/- 35.2 v 87.0 +/- 27.1 U/L, P < .01) and remained lower after both treatments. In conclusion, in IDDM patients, IL (injected immediately before the meal) may offer small different effects on lipoprotein metabolism versus RI (injected 30 minutes before the meal) that, taken together, do not seem relevant.

Acute toxic effects of fragrance products

To evaluate whether fragrance products can produce acute toxic effects in mammals, we allowed groups of male Swiss-Webster mice to breathe the emissions of five commercial colognes or toilet water for 1 h. We used the ASTM-E-981 test method to evaluate sensory irritation and pulmonary irritation. We used a computerized version of this test to measure the duration of the break at the end of inspiration and the duration of the pause at the end of expiration. Decreases in expiratory flow velocity indicated airflow limitation. We subjected the mice to a functional observational battery to probe for changes in nervous system function. The emissions of these fragrance products caused various combinations of sensory irritation, pulmonary irritation, decreases in expiratory airflow velocity, as well as alterations of the functional observational battery indicative of neurotoxicity. Neurotoxicity was more severe after mice were repeatedly exposed to the fragrance products. Evaluation of one of the test atmospheres with gas chromatography/mass spectrometry revealed the presence of chemicals for which irritant and neurotoxic properties had been documented previously. In summary, some fragrance products emitted chemicals that caused a variety of acute toxicities in mice.

Wilms tumor and multicystic dysplastic kidney disease

PURPOSE

There is ongoing controversy concerning the management of multicystic dysplastic kidney disease, particularly with regard to the potential for malignant transformation. Our report fuels the debate by adding the 2 youngest patients in whom malignancy was present from birth or developed subsequently.

MATERIALS AND METHODS

Two well documented cases of malignancy associated with multicystic dysplastic kidney disease are presented in 2 female infants (5 and 3 months old). The 5-month-old female infant was followed for multicystic dysplastic kidney disease and had no evidence of tumor either antenatally or at birth. The 3-month-old presented with hypertension and interventricular septal defect. A renal tumor was present on initial ultrasound.

RESULTS

Even though malignant degeneration is rare in multicystic dysplastic kidney disease, 9 cases have been reported in the literature so far. Of these cases 3 were Wilms tumor, 5 were renal cell carcinomas and 1 mesothelioma.

CONCLUSIONS

Our 2 cases lend support to the surgical management of multicystic dysplastic kidney disease, particularly as nephrectomy can now be performed in a day surgery setting with minimal morbidity. Only the risks of coexisting malignancy and possible malignant degeneration transformation are specifically addressed in this article. Other complications of multicystic dysplastic kidney disease such as hypertension, infection, abdominal pain, hematuria and persistent dysplastic renal tissue despite ultrasonographic resolution of multicystic dysplastic kidney disease are additional risk factors to be considered. A recommendation for nephrectomy in all cases of multicystic dysplastic kidney disease cannot be based only on these 2 cases. Several other factors must be weighed before making that decision.

Reduced frequency of severe hypoglycemia and coma in well-controlled IDDM patients treated with insulin lispro. The Benelux-UK Insulin Lispro Study Group

OBJECTIVE

Several studies have suggested that use of the short-acting insulin analog, insulin lispro, in multiple injection therapy may reduce the risk of hypoglycemia in comparison with regular insulin. This effect might be more pronounced in well-controlled patients, since intensive treatment of IDDM increases the rate of severe hypoglycemic events. This study evaluated the effects of insulin lispro on glycemic control and hypoglycemia rates in well-controlled IDDM patients.

RESEARCH DESIGN AND METHODS

This was an open, randomized, 6-month crossover study of 199 IDDM patients. Glycemic control was evaluated by HbA1c, home blood glucose measurements, and rate and timing of hypoglycemic events. At the end of the study, patients completed an evaluation form regarding therapy-related quality of life.

RESULTS

HbA1c remained constant at approximately 7.3% throughout the study. Meal-related glucose excursions were significantly lower with insulin lispro compared with regular insulin (mean -0.8 +/- 1.7 vs. 1.1 +/- 1.6 mmol/l, P < 0.001), as was the within-day variability (M value 27.7 +/- 19.7 vs. 30.2 +/- 23.1, P = 0.007). The incidence of severe hypoglycemic events (58 vs. 36, P = 0.037) including coma (16 vs. 3, P = 0.004) was significantly lower with insulin lispro than with regular insulin. Patients felt that insulin lispro increased flexibility and freedom of lifestyle.

CONCLUSIONS

In well-controlled IDDM patients, insulin lispro is associated with a lower risk of severe hypoglycemia and coma.

Failure of the Hong Kong criteria to predict the severity of acute pancreatitis

CONCLUSION

The results of the present study demonstrate that the HK criteria do not provide effective prediction of severity.

BACKGROUND

Fan et al. (1) have reported previously that a blood urea (BU) > 7.4 mmol/L and/or glucose (BG) > 11 mmol/L at the time of admission to hospital detects a severe attack of acute pancreatitis with a sensitivity of 76% and specificity of 75%. However, a similar study conducted in the West of Scotland did not confirm these findings (sensitivity 33% and specificity 83%). The reason underlying this discrepancy in prediction is unclear, but it may be because of differences in the nature of acute pancreatitis between Asian and Western populations.

AIMS

In this study we examined the predictive ability of the Hong Kong (HK) criteria in a patient population similar to that studied by Fan et al.

PATIENTS AND METHODS

A consecutive series of 130 patients experienced 135 attacks of acute pancreatitis. One-hundred-and-four (77%) attacks were mild and 31 (23%) severe (including 12 [9.0%] deaths). Eighty-nine (66%) episodes had a biliary etiology. In 19 (14%) of these episodes, the gallstones had a primary ductal origin being associated with recurrent pyogenic cholangitis.

RESULTS

Median admission BU concentrations were 5.2 mmol/L (range 3.6-32.1 mmol/L) for the mild group and 7.6 mmol/L (range 3.6-28.8 mmol/L) for the severe group. Corresponding values of BG were 7.1 mmol/L (range 2.1-17.9 mmol/L) and 8.4 mmol/L (range 3.6-28.8 mmol/L), respectively. Differences in admission BU concentrations between patients with mild and severe episodes were significant (p = 0.0001). However, differences in BG concentrations were not (p = 0.16). In the severe group, 14 patients had BU and four patients BG concentrations above the cut-off values. The HK criteria predicted severe acute pancreatitis with a sensitivity of 52% and specificity of 80%. These results compare with values of 79 and 56% for the Ranson criteria and 83 and 60% for the Glasgow score. The best prediction was provided by the APACHE II score 24 h post admission (sensitivity 79%, specificity 82%).

Spinocerebellar ataxia type 6: gaze-evoked and vertical nystagmus, Purkinje cell degeneration, and variable age of onset

Spinocerebellar ataxia type 6 (SCA6) was recently identified as a form of autosomal dominant cerebellar ataxia associated with small expansions of the trinucleotide repeat (CAG)n in the gene CACNL1A4 on chromosome 19p13, which encodes the alpha1 subunit of a P/Q-type voltage-gated calcium channel. We describe clinical, genetic, neuroimaging, neuropathological, and quantitative oculomotor studies in four kindreds with SCA6. We found strong genetic linkage of the disease to the CACNL1A4 locus and strong association with the expanded (CAG)n alleles in two large ataxia kindreds. The expanded alleles were all of a single size (repeat number) within the two large kindreds, numbering 22 and 23 repeat units. It is noteworthy that the age of onset of ataxia ranged from 24 to 63 years among all affected individuals, despite the uniform repeat number. Radiographically and pathologically, there was selective atrophy of the cerebellum and extensive loss of Purkinje cells in the cerebellar cortex. In addition, clinical and quantitative measurement of extraocular movements demonstrated a characteristic pattern of ocular motor and vestibular abnormalities, including horizontal and vertical nystagmus and an abnormal vestibulo-ocular reflex. These studies identify a distinct phenotype associated with this newly recognized form of dominant SCA.

Toxic effects of air freshener emissions

To evaluate whether emissions of a commercial air freshener produced acute toxic effects in a mammalian species, the authors allowed male Swiss-Webster mice to breathe the emissions of one commercial-brand solid air freshener for 1 h. Sensory irritation and pulmonary irritation were evaluated with the ASTM-E-981 test. A computerized version of this test measured the duration of the break at the end of inspiration and the duration of the pause at the end of expiration--two parameters subject to alteration via respiratory effects of airborne toxins. Measurements of expiratory flow velocity indicated changes in airflow limitation. The authors then subjected mice to a functional observational battery, the purpose of which was to probe for changes in nervous system function. Emissions of this air freshener at several concentrations (including concentrations to which many individuals are actually exposed) caused increases in sensory and pulmonary irritation, decreases in airflow velocity, and abnormalities of behavior measured by the functional observational battery score. The test atmosphere was subjected to gas chromatography/mass spectroscopy, and the authors noted the presence of chemicals with known irritant and neurotoxic properties. The Material Safety Data Sheet for the air freshener indicated that there was a potential for toxic effects in humans. The air freshener used in the study did not diminish the effect of other pollutants tested in combination. The results demonstrated that the air freshener may have actually exacerbated indoor air pollution via addition of toxic chemicals to the atmosphere.

Efficacy of insulin lispro in combination with NPH human insulin twice per day in patients with insulin-dependent or non-insulin-dependent diabetes mellitus. Multicenter Insulin Lispro Study Group

A common treatment regimen for patients with either insulin-dependent diabetes mellitus (IDDM) or non-insulin-dependent diabetes mellitus (NIDDM) is a combination of rapid-acting insulin and intermediate-acting insulin administered twice each day. It is usually recommended that regular human insulin be injected 30 to 45 minutes before a meal. In practice, patients often inject regular human insulin closer to mealtime, causing a higher post-prandial serum glucose level and an increased potential for hypoglycemia in the postabsorptive period. Insulin lispro, a rapid-acting insulin analogue, is best injected just before a meal because of its more rapid absorption and shorter duration of action. In 707 randomized patients, 379 with IDDM and 328 with NIDDM, we studied the effect of twice-daily insulin lispro or regular human insulin in combination with NPH human insulin (isophane insulin) on premeal, 2-hour postprandial, and bedtime glycemic control. Assessments were based on the results of a seven-point blood glucose profile, the insulin dose (by formulation and time of administration), the incidence and frequency of hypoglycemic episodes, and the glycated hemoglobin value. Treatment with insulin lispro resulted in lower postprandial glucose levels and smaller increases in glucose level after the morning and evening meals compared with treatment with regular human insulin. Overall glycemic control, frequency of hypoglycemic events, and total insulin dose were not different between the two groups. Insulin lispro in combination with NPH human insulin in a twice-per-day regimen allows injection closer to mealtime and improves post-prandial glycemic control without increasing the risk of hypoglycemia.

A robotic system for percutaneous renal access

PURPOSE

Percutaneous renal access can be challenging, particularly when the collecting system is not distended. Precise entry into a selected calyx facilitates subsequent percutaneous manipulations, but this skill requires extensive experience. In an attempt to improve accuracy while decreasing technical challenges, we developed a robotic system that automates the task of fluoroscopic image-guided percutaneous needle placement.

MATERIALS AND METHODS

The prototype system consisted of a three degree-of-freedom robot with a needle injector end-effector. Imaging was provided by a biplanar fluoroscope. After correction of image distortion and fluoroscope calibration, robot to image-space registration was completed. To validate the system's ability to insert a needle into a calyx, ex vivo porcine kidneys suspended in agarose gel and distended with iodinated contrast solution were used as a model. In situ renal access tests with three 20 kg. pigs were performed. Access was confirmed by passing a flexible wire or aspirating iodinated contrast from the collecting system.

RESULTS

The diameter of target calyces ranged from 3 to 7 mm. The in vitro accuracy of final needle tip positioning was 0.43 mm. In the ex vivo model, successful "one stick" access occurred on 10 of 12 attempts (83%). In situ access on the first attempt was successful for 6 of 12 target calyces (50%). Needle or tissue deflection accounted for each failure.

CONCLUSION

The feasibility of a robotic system to assist in the percutaneous access of small and delicate renal calyces has been demonstrated. Additional work in reducing procedural steps and correcting for tissue deflection during needle passage is necessary to improve accuracy and to allow for clinical application.

Mealtime treatment with insulin analog improves postprandial hyperglycemia and hypoglycemia in patients with non-insulin-dependent diabetes mellitus. Multicenter Insulin Lispro Study Group

BACKGROUND

Insulin lispro is an insulin analog that was recently developed particularly for a mealtime therapy. It has a fast absorption rate and short duration of action. The efficacy of insulin lispro in the clinical therapy of patients with non-insulin-dependent diabetes mellitus (NIDDM) has not been tested.

OBJECTIVES

To compare insulin lispro and human regular insulin in the mealtime treatment of patients with NIDDM.

METHODS

A 6-month, randomized, multinational (16 countries), multicenter (80 sites) clinical trial with an open-label, crossover design was performed in 722 patients with NIDDM. Insulin lispro was injected immediately before and human regular insulin 30 to 45 minutes before the meal.

RESULTS

Throughout the study, the postprandial rise in serum glucose levels was significantly lower during insulin lispro than human regular insulin treatment. At end point the rise (mean +/- SEM) in serum glucose levels was 30% lower at 1 hour (2.6 +/- 0.1 mmol/L [46.8 +/- 1.8 mg/ dL] for lispro vs 3.7 +/- 0.1 mmol/L [66.6 +/- 1.8 mg/dL] for human regular insulin) and 53% lower 2 hours after the test meal (1.4 +/- 0.1 mmol/L [25.2 +/- 1.8 mg/dL] for lispro vs 3.0 +/- 0.1 mmol/L [54.0 +/- 1.8 mg/dL] for human regular insulin) with insulin lispro compared with human regular insulin therapy (P < .001 for both intervals). During insulin lispro therapy the rate of hypoglycemia overall (P = .01) and overnight (P < .001) was lower and the number of asymptomatic hypoglycemic episodes was smaller (P = .03) than during human regular insulin therapy. Associated with a similar 13% increase (P < .001) in the total daily insulin dose, the glycosylated hemoglobin level decreased (P < .001) equally in both treatment groups. Serum lipid and lipoprotein levels remained unchanged. There were no differences in the adverse events between the 2 treatment groups.

CONCLUSIONS

Compared with human regular insulin therapy, mealtime therapy with insulin lispro reduced postprandial hyperglycemia and may decrease the rate of mild hypoglycemic episodes in patients with NIDDM.

Reduction of postprandial hyperglycemia and frequency of hypoglycemia in IDDM patients on insulin-analog treatment. Multicenter Insulin Lispro Study Group

Insulin lispro, an insulin analog recently developed particularly for mealtime therapy, has a fast absorption rate and a short duration of action. We compared insulin lispro and regular human insulin in the mealtime treatment of 1,008 patients with IDDM. The study was a 6-month randomized multinational (17 countries) and multicenter (102 investigators) clinical trial performed with an open-label crossover design. Insulin lispro was injected immediately before the meal, and regular human insulin was injected 30-45 min before the meal. Throughout the study, the postprandial rise in serum glucose was significantly lower during insulin lispro therapy. At the endpoint, the postprandial rise in serum glucose was reduced at 1 h by 1.3 mmol/l and at 2 h by 2.0 mmol/l in patients treated with insulin lispro (P < 0.001). The rate of hypoglycemia was 12% less with insulin lispro (6.4 +/- 0.2 vs. 7.2 +/- 0.3 episodes/30 days, P < 0.001), independent of basal insulin regimen or HbA1c level. The reduction was observed equally in episodes with and without symptoms. When the total number of episodes for each patient was analyzed according to the time of occurrence, the number of hypoglycemic episodes was less with insulin lispro than with regular human insulin therapy during three of four quarters of the day (P < 0.001). The largest relative improvement was observed at night. In conclusion, insulin lispro improves postprandial control, reduces hypoglycemic episodes, and improves patient convenience, compared with regular human insulin, in IDDM patients.

Improved mealtime treatment of diabetes mellitus using an insulin analogue. Multicenter Insulin Lispro Study Group

The absorption of regular human insulin from subcutaneous injection sites is delayed due to the self-association of insulin to multimeric forms. The insulin analogue insulin lispro has a weak self-association and a fast absorption rate. We examined the safety and efficacy of insulin lispro in the premeal treatment of patients with diabetes mellitus. A 12-month study was performed in 336 patients with insulin-dependent diabetes mellitus (IDDM) and 295 patients with non-insulin-dependent diabetes mellitus (NIDDM). The patients were randomized to inject either regular human insulin 30 to 45 minutes before eating, or insulin lispro immediately before each meal, in addition to basal insulin. The postprandial rise in serum glucose was lower in patients receiving insulin lispro than in those receiving regular human insulin therapy. At end point the increment was significantly lower at 1 hour (35%) and at 2 hours (64%) after the meal in IDDM patients; in NIDDM patients, the increment was nonsignificantly lower at 1 hour (19%) and significantly lower at 2 hours (48%). IDDM patients receiving insulin lispro achieved significantly lower glycated hemoglobin (HbA1c) levels in patients receiving regular human insulin (8.1% vs 8.3%). In NIDDM patients, HbA1c levels decreased equally in both treatment groups. Due to its fast absorption rate, insulin lispro improves postprandial control in diabetes. Insulin lispro can be considered one step toward optimal insulin therapy and improved patient convenience.

Immunologic effects of insulin lispro [Lys (B28), Pro (B29) human insulin] in IDDM and NIDDM patients previously treated with insulin

Insulin lispro [Lys (B28), Pro (B29) human insulin] is a rapidly absorbed analog that has diminished tendency to self-associate. In four open-label, 1-year-long international randomized trials, we contrasted the immunogenicity of insulin lispro versus regular human insulin (RHI) in patients previously treated with insulin who had IDDM or NIDDM. Using a self-blank subtraction assay, we assessed sera for the presence of insulin-specific antibodies (ISA), insulin lispro-specific antibodies (LSA), and cross-reactive antibodies (CRA). Basal insulin needs were provided either with human ultralente (UL) or NPH insulins. After 2 to 4 weeks of therapy with RHI plus UL or RHI plus NPH, 50% of patients were randomly assigned to begin insulin lispro or continue on RHI. At baseline, few pretreated patients had LSA (0-4%) and approximately 10% had ISA, whereas 41-45% of patients with IDDM and 23-27% of patients with NIDDM had CRA (IDDM vs. NIDDM, P < 0.001). Within studies, no significant differences were noted over time in ISA, LSA, or CRA attributable to the type of short-acting insulin. When data were pooled, inconsistent changes were noted in ISA and LSA (LSA were greater in NIDDM vs. IDDM at baseline, P = 0.001, and ISA were greater in IDDM vs. NIDDM at 6 months, P = 0.007). Significant levels of CRA were more common in IDDM at all times (P < 0.001, P = 0.022, and P = 0.002 at baseline, 6 months, and 12 months, respectively). For patients receiving insulin lispro, no significant changes occurred in antibody status among IDDM and NIDDM patients throughout the study (became positive, remained positive, became negative, or remained negative). IDDM patients were more likely to develop or maintain CRA levels (P = 0.008 vs. NIDDM), whereas antibody levels were comparable among positive individuals. No evidence was noted that insulin lispro differs in immunogenicity from RHI in previously treated IDDM and NIDDM patients.

Predicted and actual BCNU concentrations in normal rabbit brain during intraarterial and intravenous infusions

Normal New Zealand White rabbits were used to compare theoretical brain concentrations (based upon pharmacokinetic modeling) with actual experimental concentrations of BCNU following intraarterial (IA) or intravenous (IV) infusions. IA infusion therapy for brain tumor patients has been promising based upon theoretical predictions but of limited effectiveness clinically. Experimentally-measured rabbit carotid artery flow rates (63.9 +/- 3.4 ml/min) [mean +/- 1 sem] and BCNU systemic clearances (197 +/- 10.2 ml/min) predicted a theoretical IA advantage of 4.1 +/- 0.2. Ipsilateral brain concentrations of BCNU during and after IA infusions (20 mg/min/m2 over 15 minutes) were: 16.2 +/- 2.9, 19.0 +/- 3.9, 20.3 +/- 2.8, 4.8 +/- 2.5, 2.1 +/- 1.5, and 1.7 +/- 1.6 micrograms/gm brain at 5, 10, 15, 25, 35, and 45 minutes after infusion start. Mean concentrations at same time points in contralateral hemisphere (IA infusions) were: 7.1 +/- 1.8, 9.0 +/- 1.8, 10.3 +/- 0.7, 4.2 +/- 1.4, 2.2 +/- 1.2, 2.0 +/- 1.5 micrograms/gm brain. Concentrations in either hemisphere during IV infusions were similar to contralateral hemisphere during IA infusions. Comparison of ipsilateral: contralateral hemisphere ratios during and after IA infusions were: 3.2 +/- 0.4, 2.6 +/- 0.3, 2.2 +/- 0.3, 1.1 +/- 0.3, 1.0 +/- 0.4, and 0.9 +/- 0.3 at the same time points. Although these data show higher drug concentrations with IA infusions, actual values were considerably less than predicted by theoretical modeling. This discrepancy between theoretical and experimental results emphasizes need for further study of causes and remedies so that IA therapy can achieve better drug concentrations with less toxicity.

Response to regional chemotherapy in patients with variant hepatic arterial anatomy

Regional chemotherapy for colorectal liver metastases is conventionally delivered by a catheter inserted into the gastroduodenal artery. However, up to 40 per cent of patients have 'unconventional' hepatic arterial anatomy. The response rate to regional chemotherapy was examined in 28 patients with normal and in 17 with variant hepatic arterial anatomy. There was no significant difference in response rates between the two groups.