Comparative effectiveness and cost-effectiveness of natalizumab and fingolimod in rapidly evolving severe relapsing-remitting multiple sclerosis in the United Kingdom

AIM

To evaluate the real-world comparative effectiveness and the cost-effectiveness, from a UK National Health Service perspective, of natalizumab versus fingolimod in patients with rapidly evolving severe relapsing-remitting multiple sclerosis (RES-RRMS).

METHODS

Real-world data from the MSBase Registry were obtained for patients with RES-RRMS who were previously either naive to disease-modifying therapies or had been treated with interferon-based therapies, glatiramer acetate, dimethyl fumarate, or teriflunomide (collectively known as BRACETD). Matched cohorts were selected by 3-way multinomial propensity score matching, and the annualized relapse rate (ARR) and 6-month-confirmed disability worsening (CDW6M) and improvement (CDI6M) were compared between treatment groups. Comparative effectiveness results were used in a cost-effectiveness model comparing natalizumab and fingolimod, using an established Markov structure over a lifetime horizon with health states based on the Expanded Disability Status Scale. Additional model data sources included the UK MS Survey 2015, published literature, and publicly available sources.

RESULTS

In the comparative effectiveness analysis, we found a significantly lower ARR for patients starting natalizumab compared with fingolimod (rate ratio [RR] = 0.65; 95% confidence interval [CI], 0.57-0.73) or BRACETD (RR = 0.46; 95% CI, 0.42-0.53). Similarly, CDI6M was higher for patients starting natalizumab compared with fingolimod (hazard ratio [HR] = 1.25; 95% CI, 1.01-1.55) and BRACETD (HR = 1.46; 95% CI, 1.16-1.85). In patients starting fingolimod, we found a lower ARR (RR = 0.72; 95% CI, 0.65-0.80) compared with starting BRACETD, but no difference in CDI6M (HR = 1.17; 95% CI, 0.91-1.50). Differences in CDW6M were not found between the treatment groups. In the base-case cost-effectiveness analysis, natalizumab dominated fingolimod (0.302 higher quality-adjusted life-years [QALYs] and £17,141 lower predicted lifetime costs). Similar cost-effectiveness results were observed across sensitivity analyses.

CONCLUSIONS

This MSBase Registry analysis suggests that natalizumab improves clinical outcomes when compared with fingolimod, which translates to higher QALYs and lower costs in UK patients with RES-RRMS.

Factors predicting screen time related to physical and behavioural complaints in primary school children

BACKGROUND AND OBJECTIVE

Physical and behavioural problems from extended usage of electronic devices are issues among primary school children. This study is aimed to investigate the prevalence of physical and behavioural complaints arising from the electronic device usage and to identify the potential factors that predicted the complaints.

METHODS

This was a primary school-based cross-sectional study using multistage cluster sampling, conducted at Bau district in Sarawak, Malaysia in 40 primary schools. A questionnaire was used to collect information of usage pattern in insufficient lighting, timing and position. The physical and behavioural complaints were traced. Data analysis was performed using SPSS version 22. A p-value < 0.05 with 95% CI was considered as statistically significant.

RESULTS

About 52.8% of the 569 students used digital devices in a bright room, 69.8% in the day time and 54.4% in sitting position. The physical complaints were headache (32.9%), neck, shoulder and back pain (32.9%) followed by by eye strain (31.8%). Regarding behavioural problems, 25.7% of the students had loss of interest in study and outdoor activities (20.7%), skipped meals (19.0%) and arguments/disagreements with parents (17.9%). After logistic regression analysis, the lying position (OR=1.71, 95% CI: 1.096, 2.688) and darkroom lighting (OR=2.323 95% CI: 1.138, 4.744) appeared to be potential predictors of the complaint.

CONCLUSION

One-quarter of the students studied experienced physical complaints, and one-fifth had behavioural problems associated with the use of electronic devices. Lying position and darkroom lighting are the potential predictors of complaints. Therefore, we suggest that the children should use electronic devices in the sitting position with adequate room lighting.

Perioperative intravenous contrast administration and the incidence of acute kidney injury after major gastrointestinal surgery: prospective, multicentre cohort study

BACKGROUND

This study aimed to determine the impact of preoperative exposure to intravenous contrast for CT and the risk of developing postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery.

METHODS

This prospective, multicentre cohort study included adults undergoing gastrointestinal resection, stoma reversal or liver resection. Both elective and emergency procedures were included. Preoperative exposure to intravenous contrast was defined as exposure to contrast administered for the purposes of CT up to 7 days before surgery. The primary endpoint was the rate of AKI within 7 days. Propensity score-matched models were adjusted for patient, disease and operative variables. In a sensitivity analysis, a propensity score-matched model explored the association between preoperative exposure to contrast and AKI in the first 48 h after surgery.

RESULTS

A total of 5378 patients were included across 173 centres. Overall, 1249 patients (23·2 per cent) received intravenous contrast. The overall rate of AKI within 7 days of surgery was 13·4 per cent (718 of 5378). In the propensity score-matched model, preoperative exposure to contrast was not associated with AKI within 7 days (odds ratio (OR) 0·95, 95 per cent c.i. 0·73 to 1·21; P = 0·669). The sensitivity analysis showed no association between preoperative contrast administration and AKI within 48 h after operation (OR 1·09, 0·84 to 1·41; P = 0·498).

CONCLUSION

There was no association between preoperative intravenous contrast administered for CT up to 7 days before surgery and postoperative AKI. Risk of contrast-induced nephropathy should not be used as a reason to avoid contrast-enhanced CT.

1247Similar rate of thermal esophageal lesions are found in patients alternatively assigned to high power short duration (70W, 8s) vs. lesion index guided (35W) ablation for atrial fibrillation

Background

wide antral pulmonary vein (PV) catheter ablation (CA) in patients with atrial fibrillation (AF) is safe and effective when permanent trans-mural lesions are achieved without causing harm to surrounding anatomical structures. Atrio-esophageal fistula, due to its high mortality, is the most dreadful complication related to CA for AF, therefore alternative radiofrequency (RF) approaches to reduce or eliminate this complication are currently studied. The shallower but wider lesions of high power short duration (HPSD) ablation might represent a safe alternative.

Purpose

to compare the rate of thermal esophageal lesions in patients with paroxysmal and persistent AF undergoing CA assigned to the 2 different RF modality.

Methods

one-hundred patients with paroxysmal and 100 with persistent AF will be alternatively assigned to undergo CA with the FlexAbility™ (HPSD group: 70W, 41°, 8 seconds) or the TactiCath™ (LSI-group: 35W, 41°, LSI: 5-5.5 posterior wall, up to 6 anywhere else) catheter. A 3-D mapping system, a steerable sheath and adenosine-test (30mg) were used in all patients. Posterior wall (PW) isolation in addition to PV isolation was performed in all, and patients with persistent AF were additionally treated with mitral and cavotricuspid isthmus ablation. Insertion of an esophageal probe was always attempted, and all patients underwent upper endoscopy 24 to 48 hours after CA.

Results

between June and October 2019, 71 patients (68 ± 10 years old, 32 (45%) female, 44 (60%) paroxysmal AF, AF duration 58 ± 81 months) were alternatively assigned to HPSD (36, 51%) or LSI-guided (35, 49%) ablation. No differences in clinical characteristics were found between groups. After 45 ± 18min and 30 ± 14 min of procedural and RF time, all PVs were isolated, and all spontaneous and adenosine-induced reconnections treated. Successful PW isolation was achieved with an additional 8 ± 3 and 7 ± 3 min of procedural and RF time. When HPSD and LSI-guided groups are compared, a similar rate of clinically non-relevant and self-healing thermal lesions at endoscopy was found (10, 27.8% vs. 10, 28.6%). Independent of the treatment group, a higher peak temperature identified patients with esophageal lesions (43.2° vs. 42°; P=.0065). A peak temperature value of 43.1° best identify patients most likely to develop thermal lesions (AUC 0.71, SE 84%, SP 39%). Interestingly, none of the 11 patients in whom esophageal probe insertion was not possible or attempted developed thermal lesions in comparison to 20 (33%) patients who underwent esophageal temperature monitoring (P=.0046). Conclusions: no difference in thermal induced esophageal lesions were found when the two different RF approach (HPSD vs. LSI guided) were compared. Interestingly, lack of temperature monitoring with an esophageal probe is associated with no thermal lesions at endoscopy.

Effects of endocrine disruptor furan on reproductive physiology of Sprague Dawley rats: An F1 Extended One-Generation Reproductive Toxicity Study (EOGRTS)

The present study investigated the reproductive toxicity of furan in an Extended One-Generation Reproductive Toxicity Study in rats. Sprague Dawley F0 weaning rats (30 per sex per group) were exposed to furan orally at 0, 1, 2.5, 5, and 10 mg kg^-1 for 10 weeks (males) and 2 weeks (females) and then mated. Results of F0 indicated that in the furan-treated groups (5 mg kg^-1 and 10 mg kg^-1), body weight (bw) gain decreased during prebreed and gestational period while increased during lactation periods. F0 animals prebreeding exposure resulted in head tilt and foot splay at 10 mg kg^-1. Number of live pups at birth were decreased (p < 0.001) at 10 mg kg^-1. At postnatal day (PND) 70, a significant (p = 0.03) decrease in testosterone levels of male rats and estrogen levels of female rats (p = 0.05) was observed in 10 mg kg^-1 furan-treated group in F1 generation. Luteinizing hormone, follicle-stimulating hormone, and progesterone levels were also reduced, but their reduction was not statistically significant in all groups. In higher dose furan group (10 mg kg^-1), testicular and ovarian weights were reduced in F1 generation at PND 70, with decreased daily sperm production (p = 0.01) and disturbed estrous cyclicity (p < 0.01). Some histopathological changes were also observed in testis and ovaries in groups whose parents were previously exposed to 10 mg kg^-1 bw of furan group. Based on the above results, it is suggested that exposure to food-based contaminant furan induced remarkable changes in the F0 (parental stage) and F1 (offspring, pubertal, and adult stage) generations of Sprague Dawley rats.

Comparative study of environmental pollutants bisphenol A and bisphenol S on sexual differentiation of anteroventral periventricular nucleus and spermatogenesis

BACKGROUND

Bisphenol A is well known endocrine-disrupting chemical while Bisphenol S was considered a safe alternative. The present study aims to examine the comparative effects of xenobiotic bisphenol-A (BPA) and its substitute bisphenol-S (BPS) on spermatogenesis and development of sexually dimorphic nucleus population of dopaminergic neurons in the anteroventral periventricular nucleus (AVPV) of the hypothalamus in male pups.

METHODS

Sprague Dawley rat's pups were administered subcutaneously at the neonatal stage from postnatal day PND1 to PND 27. Thirty animals were divided into six experimental groups (6 animals/group). The first group served as control and was provided with normal olive oil. The four groups were treated with 2 μg/kg and 200 μg/kg of BPA and BPS, respectively. The sixth group was given with 50 μg/kg of estradiol dissolved in olive oil as a standard to find the development of dopaminergic tyrosine hydroxylase neurons in AVPV regions. Histological analysis for testicular tissues and immunohistochemistry for brain tissues was performed.

RESULTS

The results revealed adverse histopathological changes in testis after administration of different doses of BPA and BPS. These degenerative changes were marked by highly significant (p < 0.001) decrease in tubular and luminal diameters of seminiferous tubule and epithelial height among bisphenols treated groups as compared to control. Furthermore, significantly increased (p < 0.001) TH-ir cell bodies in the AVPV region of the brain with 200 μg/kg dose of BPA and BPS was evident.

CONCLUSION

It is concluded that exposure of BPA and BPS during a critical developmental period can structural impairments in testes and affects sexual differentiation of a dimorphic dopaminergic population of AVPV region of hypothalamus in the male brain.

Ileal Tuberculosis Causing Hypercalcemia and Renal Failure

Hypercalcemia rarely causes acute pancreatitis due to secretory block in the pancreas and damage by accumulated proteases. Hypercalcemia, though described in granulomatous disorders, is uncommon in tuberculosis. Acute kidney injury is known to occur with acute pancreatitis, secondary to sepsis and septic shock; however, acute pancreatitis resulting in acute cortical necrosis is very rare. We report a 22-year-old woman, who presented with pain abdomen and vomiting. She was found to have features of acute pancreatitis, both biochemically and radiologically. She had hypercalcemia on presentation and this was attributed to be the cause for pancreatitis as other causes were ruled out. 1, 25-dihydroxyvitamin D level was high with normal parathyroid hormone level. Whole-body positron emission tomography-computed tomography showed increased fluorodeoxyglucose uptake in the terminal ileum and histology from that area showed noncaseating granuloma with acid-fast bacilli in the tissue. She was treated with antituberculosis therapy; hypercalcemia improved over a period of time and pancreatitis resolved. She developed anuric renal failure, and kidney biopsy showed patchy acute cortical necrosis. She is dialysis dependent at the end of 6 months. To the best of our knowledge, this is the first case report of a patient with ileal tuberculosis presenting with hypercalcemia and acute pancreatitis. This case is reported due to the rarity of extrapulmonary tuberculosis presenting with symptomatic hypercalcemia, acute pancreatitis, and acute renal cortical necrosis.

Is general anaesthesia preferable to conscious sedation in the treatment of acute ischaemic stroke with intra-arterial mechanical thrombectomy? A review of the literature

INTRODUCTION

Intra-arterial mechanical thrombectomy (IAMT) is an endovascular technique that allows for the acute retrieval of intravascular thrombi and is increasingly being used for the treatment of acute ischaemic stroke (AIS). There are currently two anaesthetic options during IAMT: general anaesthesia (GA) and conscious sedation (CS). The decision to use GA versus CS is the source of controversy, as it requires careful balance between patient pain, movement and airway protection whilst minimising time delay and haemodynamic fluctuations. This review examines and summarises the evidence for the use of GA versus CS in the treatment of AIS by IAMT.

METHODS

Studies were identified using systematic bibliographic searches. The five applicable studies were analysed with reference to overall outcomes and the key parameters that govern the decision to use GA or CS. The key parameters included the impact of GA and CS on pain, complication rates, time delays, airway protection and haemodynamic stability.

RESULTS

Several retrospective analyses have shown that the use of GA is associated with adverse outcomes.

CONCLUSION

Intra-arterial mechanical thrombectomy under general anaesthesia is associated with poor outcomes in observational studies. It is reasonable to offer conscious sedation as the preferred option where adverse patient factors such as agitation are lacking.

Status of pediatric eye care in India

Purpose:

To document the status of pediatric eye care in India.

Materials and Methods:

A list of institutions providing eye care was compiled from various sources, including government officials, professional bodies of ophthalmologists, and national and international non-governmental organizations (NGO) working in the field of eye care in India. A questionnaire on eye care services was sent to all known eye care institutions in the country. Workshops and regional meetings were organized to maximize response. Validity of data was ensured by observational visits to 10% of the institutions who responded.

Results:

Out of 1204 institutions contacted, 668 (55.5%) responded to the questionnaire. Of these, 192 (28.7%) reported that they provided pediatric eye care services. A higher proportion (48.3%) of NGO hospitals reported separate pediatric ophthalmology units compared to other providers (P< 0.001). Eighty per cent of advanced care eye hospitals had dedicated outpatient, and 40% had dedicated inpatient facilities for children (P< 0.001). The advanced eye care hospitals attended to a larger number of pediatric clients (P < 0.001), and performed more pediatric eye surgeries compared to secondary and tertiary care hospitals (P < 0.001). Eighty- three per cent of advanced care centers and 72.4% of NGO hospitals had an anesthesiologist for pediatric eye service. Refractive error was the commonest reason for seeking service. The commonest surgical procedure was pediatric cataract surgery followed by squint surgery.

Conclusion:

Pediatric eye care services are not adequate in India.

Work capacity and surgical output for cataract in the national capital region of Delhi and neighbouring districts of north India

OBJECTIVES

To ascertain time taken for cataract surgery by ophthalmologists in the National Capital Region of Delhi and neighbouring districts, to determine what work output is feasible with the available ophthalmologists.

METHODS

The time-motion study was conducted during January to June 2006 in the National Capital Region of Delhi and neighbouring districts in North India. Data was collected by observing all activities from entry of a patient into the operating theatre to exit. A total of 156 cataract surgeries performed by 45 ophthalmologists in 38 hospitals were observed. A stop watch was used to record activity time, rounded off to the nearest 10 seconds. Case duration, surgical and clinical times were calculated.

RESULTS

Ninety percent ophthalmologists completed surgery in 41.3 minutes. The 10th and 90th percentile for case duration time was 15.5 and 78.4 minutes respectively. Median surgical time was lowest for ophthalmologists working in the NGO sector (10 minutes), compared to the government (23.5 minutes), and private sector (17.3 minutes). Cataract surgical output can be increased in the country if operation theatre time is utilized optimally.

The predictive value of ICP as compared to magnetic resonance imaging in comatose patients after head injury

INTRODUCTION

While highly increased intracranial pressure (ICP) is of high predictive value indicating a fatal outcome, the predictive value of moderately increased ICP early after head injury remains uncertain. We compared the predictive value of ICP to the predictive value of magnetic resonance imaging (MRI) early after head injury.

METHODS

55 patients with a Glasgow Coma Scale (GCS) of less than 8, for more than 24 hours after head injury were investigated. Outcome was classified according to the Glasgow Outcome Scale (GOS). All patients received registration of ICP upon arrival at the hospital and an initial cranial computerized tomography scan. An MRI study was subsequently performed within 10 days of admission. The highest mean ICP registered within one hour in the first day of admission and the location of lesions as identified by MRI were related with outcome.

RESULTS

ICP was neither related with mortality nor with GOS of survivors. The location of lesions as depicted by MRI proved to be statistically significantly related with the GOS (p < 0.001). Age proved to be clearly and significantly related with outcome (p = 0.019).

CONCLUSIONS

Our current MRI findings suggest that the location of the initial brain injury lesion correlates with outcome at 6 months. No such correlation could be identified for intracranial pressure on the first day after head injury (p = 0.766).

Current estimates of blindness in India

BACKGROUND

Evidence based planning has been the hallmark of the blindness control programme in India. A nationwide survey was undertaken in 1999-2001 to document the magnitude and causes of blindness.

METHODS

One district each in 15 populous states was covered. 25 clusters were randomly selected in each district and all individuals aged 50 years and above were enumerated. Presenting and best corrected vision was recorded using retroilluminated logMAR tumbling E charts and detailed eye examination was offered.

RESULTS

The response rate was 89.3%. Presenting vision <6/60, in the better eye, was observed in 8.5% (95% CI: 8.1 to 8.9). Age, sex, residence, literacy, and working status were associated with blindness. The highest risk was among those aged 70+ and the illiterate. Cataract was responsible for 62.4% of bilateral blindness. Prevalence of cataract blindness was 5.3% (95% CI: 4.97 to 5.62). Reduction in blindness prevalence among people aged 50 years and above was observed compared to earlier studies.

CONCLUSION

Blindness control efforts seem to have played a part in arresting the increasing prevalence of blindness in India and there is hope that the goals of the "Vision 2020--right to sight" initiative can be achieved if there is strong political will and prioritised action.

Drowning of babies in bath seats: do they provide false reassurance?

AIMS

To investigate the problem of children drowning in bath seats by examining case reports, by looking at the epidemiology of bath drowning in children under two years of age and by reviewing the literature.

METHODS

We describe two babies: one who drowned and one nearly drowned in the bath whilst in a bath seat. We examined the RoSPA/RLSS UK database of cases of children under two years drowning in the bath for the years 1989-2003. Cases are ascertained through a press cutting system. We conducted an all language literature search of original articles, references, textbooks and conference abstracts 1951-October 2004 in 11 standard databases.

RESULTS

The two cases illustrate how parents can have a false sense of security with bath seats. We found six cases of babies under two years drowning in the UK associated with bath seats in the time period 1989-2003. They were all boys: five of the six were under one year of age. This compared with 47 children of similar age drowning in the bath not associated with a bath seat. The literature is sparse with only four papers since 1966.

DISCUSSION

A baby drowning after being placed in a bath seats is a rare but definite cause of death. Bath seats appear to give a false sense of security (even if not encouraged by the manufacturers). It is unclear whether putting a baby in a bath seat represents an increased risk of drowning compared with a baby without a seat. Without knowing the numbers of mothers that use bath seats it is difficult to come to firm conclusions on the risks to babies. New research is needed to clarify this issue. Whether in a seat or not it is clear that the main risk to babies in the bath is being left unsupervised.

Growth factor protection against cytokine-induced apoptosis in neonatal rat islets of Langerhans: role of Fas

Treatment of neonatal rat islets of Langerhans with combined cytokines (interleukin-1beta 10(-10) M, tumour necrosis factor-alpha 10(-10) M, interferon-gamma 5 U/ml) led to extensive cell death, which was potentiated by Fas activation with the anti-Fas cytolytic antibody JO2. Pre-treatment with insulin (25 ng/ml) or insulin-like growth factor-1 (10(-8)M) gave only partial protection against cell killing, but prevented the Fas-mediated component. In the absence of cytokine treatment, Fas-mediated killing was not observed.

Effectiveness of fixed minidose warfarin in the prevention of thromboembolism and vascular death in nonrheumatic atrial fibrillation

Adjusted-dose warfarin is effective for stroke prevention in patients with nonrheumatic atrial fibrillation (AF), but the risk of bleeding is high, especially among the elderly. Fixed minidose warfarin is effective in preventing venous thromboembolism with low risk of bleeding and no need for frequent clinical monitoring. Patients > 60 years with nonrheumatic AF were randomized in an open-labeled trial to receive fixed minidose warfarin (1.25 mg/day) or standard adjusted-dose warfarin (International Normalized Ratio [INR] between 2.0 and 3.0). Primary outcome events were ischemic stroke, peripheral or visceral embolism, cerebral or fatal bleeding, and vascular death. Secondary end points were major bleeding, myocardial infarction, and death. This study was discontinued before completion in light of publication of the Stroke Prevention in Atrial Fibrillation III trial, which indicated that low-intensity fixed-dose warfarin treatment (i.e., INR < 1.5) was insufficient for stroke prevention in high-risk patients with nonrheumatic AF. From a total of 1,209 considered patients, 303 were randomized to be studied (150 in the minidose group and 153 in the adjusted-dose group). Mean follow-up was 14.5 months. The rate of cumulative primary events was 11.1% (95% confidence intervals [CI] 4.0 to 18.2) in the fixed minidose group and 6.1% (95% CI 1.1 to 11.1) in the adjusted-dose group (p = 0.29). The rate of ischemic stroke was significantly higher in the minidose group (3.7% vs 0% per year, p = 0.025). Major bleedings were more frequent in standard treatment group (2.6% vs 1% per year, p = 0.19). Most thromboembolic complications occurred at INRs < 1.2, whereas the majority of hemorrhages occurred at INRs > 3.0. No significant difference in primary outcome events was observed in the abbreviated study. However, the significantly increased occurrence of ischemic stroke in the fixed minidose warfarin group suggests that this regimen does not protect patients with nonrheumatic AF.

Transforming growth factor beta 1 prevents cytokine-mediated inhibitory effects and induction of nitric oxide synthase in the RINm5F insulin-containing beta-cell line

The aim of this study was to examine if the growth factor, transforming growth factor beta 1 (TGF beta 1), could prevent induction of nitric oxide synthase and cytokine-mediated inhibitory effects in the insulin-containing, clonal beta cell line RINm5F. Treatment of RINm5F cells for 24 h with interleukin-1 beta (IL-1 beta) (100 pM) induced expression of nitric oxide synthase and inhibited glyceraldehyde-stimulated insulin secretion. Combinations of IL-1 beta (100 pM), tumour necrosis factor-alpha (100 pM) and interferon-gamma (100 pM) reduced RINm5F cell viability (determined by the 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium (MTT) reduction assay) and de novo protein synthesis, as measured by incorporation of radiolabelled amino acids into perchloric acid-precipitable protein. Pretreatment of RINm5F cells with TGF beta 1 (10 pM) for 18 or 24 h, prior to the addition of either IL-1 beta or combined cytokines, prevented cytokine-induced inhibition of insulin secretion, protein synthesis and the loss of cell viability. TGF beta 1 pretreatment inhibited cytokine-induced expression and activity of nitric oxide synthase in RINm5F cells as determined by Western blotting and by cytosolic conversion of radiolabelled arginine into labelled citrulline and nitric oxide. Chemically generated superoxide also induced expression of nitric oxide synthase possibly due to direct activation of the nuclear transcription factor NF kappa B, an effect prevented by both an antioxidant and TGF beta 1 pretreatment. In conclusion, the mechanism of action of TGF beta 1 in blocking cytokine inhibitory effects was by preventing induction of nitric oxide synthase.

Insulin-like growth factor I reverses interleukin-1beta inhibition of insulin secretion, induction of nitric oxide synthase and cytokine-mediated apoptosis in rat islets of Langerhans

We have previously observed that treatment of rat islets of Langerhans with interleukin-1beta for 12 h results in nitric oxide-dependent inhibition of insulin secretion, while 48 h treatment increased rates of islet cell death by apoptosis. Here, we demonstrate that interleukin-1beta-mediated nitric oxide formation and inhibition of insulin secretion are significantly reduced by 24 h pretreatment of rat islets of Langerhans with insulin-like growth factor I (IGF-I). IGF-I decreased cytokine induction of nitric oxide synthase in islets. Use of an arginine analogue in culture or IGF-I pretreatment of islets were also effective in protecting islets against cytokine-mediated apoptotic cell death. We conclude that IGF-I antagonises inhibitory and cytotoxic effects of cytokines in rat islets.

Ventricular development and function in complete transposition: angiocardiographic evaluation

We studied 50 left ventricular cineangiograms and 41 right ventricular cineangiograms of 40 patients with usual atrial arrangement (situs solitus) together with concordant atrioventricular and discordant ventriculo-arterial connexions (complete transposition), catheterized between 1 day and 12 months of age. Our purpose was to evaluate ventricular development and function. The patients were subdivided on the basis of associated lesions into groups with intact ventricular septum; with ventricular septal defect; with ventricular septal defect together with pulmonary stenosis and with pulmonary stenosis in isolation. Each group was further separated according to age into those patients below and above 60 days. Ventricular volumes, ejection fraction and the ratio between systolic pressure and end-systolic volume were evaluated for both ventricles. The left ventricular mass, stress, and the ratio of stress to end-systolic volume were also calculated. A volume overload leads to increased left ventricular volume even at birth. With an intact ventricular septum, the left ventricle in patients with complete transposition is normal at birth and also during the first weeks of life. Myocardial mass, however, does not increase proportionately with increase in volume as the patient grows and it remains inadequate by the age of one year. The left ventricular mass is also inadequate in patients with associated anomalies when the left ventricular pressure is less than 60 mm Hg. Moreover, the left ventricle in presence of an intact ventricular septum presents a decrease in contractility during the first year of life despite the finding of a satisfactory arterial oxygen saturation. The right ventricle has a normal volume at birth which increases during the first year due to a greater diastolic filling following atrial septostomy. We noted a progressive decrease in ejection fraction, however, which is related to various factors including a reduction in contractility.

Rhythm and conduction disturbances in isolated, congenitally corrected transposition of the great arteries

The incidence and types of rhythm and conduction disturbances in 11 male and 6 female patients with congenitally corrected transposition of the great arteries and no other intrinsic complicating anomalies were studied. Patient age ranged from 5 to 54 years; follow-up ranged from 5 to 37 years. Surface electrocardiograms were recorded in each patient; 15 also underwent 24-hour Holter monitoring and 10 underwent electrophysiologic study. The conduction system of a 54-year-old woman who died suddenly, with complete atrioventricular (AV) block since age 30 years, was studied by serial histologic sections. Fifteen patients were asymptomatic and 2 reported repeated episodes of palpitation since childhood. Ten patients presented with a normal PR interval and 2 with first-degree AV block (12%). Five patients had complete AV block (29%), but none had had it at birth; first- and second-degree AV block preceded complete AV block in 2 patients. The morphologic pattern and duration of QRS suggested a junctional rhythm in 4 patients and an idioventricular pacemaker in 1 patient. Electrophysiologic studies confirmed that the complete AV block site was supra-Hisian in 2 patients and proximal to the His bundle bifurcation in 1 patient. However, histologic investigation disclosed fibrosis and disruption of the proximal nonbifurcating His bundle in the patient who died suddenly. In 2 patients with recurrent supraventricular tachycardia, electrophysiologic studies suggested reentry through James fibers (or dual AV nodal pathway) in 1 and the presence of a left lateral accessory AV pathway in the other. Holter monitoring showed a high incidence of ventricular arrhythmias.