Poisoning

Conclusion In summary, environmental emergencies account for a major portion of mortality and morbidity in children. Many of these injuries are preventable and hence programmes aimed at public education and preventative measures should yield gratifying results. When these measures have failed, prompt assessment and resuscitation offers the child the best chance of intact survival.     

Loeys-Dietz syndrome: Intermediate-term outcomes of medically and surgically managed patients

Objectives

Loeys-Dietz syndrome (LDS) is an aggressive connective tissue disorder associated with increased risk of aortic dissection and aneurysm rupture at an early age and smaller aortic diameters. We report our experience with LDS to better understand its natural history and treatment outcomes and help establish treatment guidelines.

Effect of single dose surfactant on pulmonary function

Sequential changes in pulmonary mechanics in response to single dose exogenous surfactant instillation were studied in 15 preterm neonates who had hyaline membrane disease (HMD). The infants were part of a larger double-blind national study. Birth weight ranged from 0.88 to 1.55 kg, and gestational age was between 27 to 32 wk. There were six infants in the surfactant group and nine in the placebo group. Pulmonary mechanics were studied before and at 2, 24, 60, and 96 h after surfactant or sham instillation using a pneumotachometer and an esophageal balloon catheter. The variables studied were dynamic compliance (Cdyn), pulmonary resistance, work of breathing, tidal volume, and minute ventilation. Infants in the surfactant group showed an immediate and significant (p less than .05) improvement in gas exchange ratio, decreased mean airway pressure (9.7 +/- 0.9 to 7.9 +/- 0.4 cm H2O) and airway resistance (133 +/- 6.3 to 92 +/- 14.9 cm H2O/L.sec) (p less than .05). Changes in Cdyn were noted only at 24 h after surfactant instillation. In the control group, gradual improvement occurred after the initial deterioration. The findings suggest that the immediate improvement in oxygenation after surfactant instillation is the result of factors other than changes in lung compliance, such as improved ventilation/perfusion and better capillary stability with decreased leakage of fluid into alveoli.     

Chloride transport in primary cultures of rabbit colonocytes at different stages of development

BACKGROUND & AIMS: Ontogeny of colonic Cl- transport and its regulation has been characterized inadequately. The aim of this report was to study developmental changes in Cl- transport in primary cultures of rabbit distal colonocytes. METHODS: Colonocytes from newborn (7-9 days old), weanling (25-28 days old), and adult (6 months old) rabbits were cultured for 24 hours on a collagen IV matrix, and Cl- transport was measured using the fluoroprobe 6-methoxyquinolyl acetoethyl ester. RESULTS: Cl- permeabilities were dependent on [Cl-]o with maximal rates (in millimoles per liter per second) at [Cl-]o = 75 mmol/L (newborns; 0.15 +/- 0.04; weanlings; 0.2 +/- 0.02; and adults, 0.32 +/- 0.06). Influx was inhibited significantly by the Cl- channel (50 mumol/L diphenylamine-2-carboxylate) and the Na(+)-K(+)- 2Cl- cotransport (10 mumol/L furosemide) inhibitors. The adenosine 3',5'-cyclic monophosphate (cAMP)-dependent secretagogues, prostaglandin E1 (1 mumol/L), forskolin (1 mumol/L), and 8-bromo-cAMP (100 mumol/L), and the protein kinase C activator, phorbol 12-13 dibutyrate (1 mumol/L), increased Cl- influx significantly in all groups with adults showing greatest stimulation. However, taurodeoxycholate (0.025-1 mmol/L) had an effect only in the adult and the guanosine 3',5'-cyclic monophosphate (cGMP) activators STa and 8-bromo-cGMP had no effect. CONCLUSIONS: Rabbit distal colonocytes possess inhibitor-sensitive Cl- permeabilities even in neonates. However, the ontogeny of their regulation depends on the secretagogue-signaling pathway. (Gastroenterology 1996 Dec;111(6):1541-50)     

Effect of chromium on carbohydrate and lipid metabolism in a rat model of type 2 diabetes mellitus: the fat-fed, streptozotocin-treated rat

Chromium supplements are widely used as an alternative remedy for type 2 diabetes mellitus (T2DM). In vitro study findings show that chromium picolinate (CrPic) may improve insulin sensitivity by enhancing intracellular insulin receptor. In this study, we evaluated the metabolic effects of CrPic in a rat model of T2DM. Male Sprague-Dawley rats (n = 45, 8 weeks old) were divided into 3 groups. The controls (group I) received a standard diet (12% of calories as fat); group II received a high-fat diet (HFD; 40% of calories as fat) for 2 weeks and then were intraperitoneally injected with streptozotocin (STZ, 40 mg/kg; HFD/STZ) on day 14; group III rats were given group II diets with the addition of 80 microg CrPic per kilogram body weight per day. The addition of CrPic in the group III treatment lowered glucose by an average of 63% (P < .001), total cholesterol by 9.7% (P < .001), and triglycerides by 6.6% (P < .001) compared with group II treatment. Compared with group II, CrPic treatment also lowered free fatty acid levels by 24% (P < .001), blood urea by 33% (P < .05), and creatinine level by 25% (P < .01), and reduced the severity of glomerular sclerosis (P < .0001). Histopathologic findings suggest that the CrPic-treated group had normal renal tubular appearance compared with the HFD/STZ-treated group. Normal appearance of hepatocytes was observed in the CrPic-treated group. These results showed that CrPic has marked beneficial effects against microvascular complications. In conclusion, HFD/STZ rats provide a novel animal model for T2DM. Further treatment with CrPic for 10 weeks significantly ameliorated changes in metabolic risk factors including favorable changes in histopathology of the liver, kidney, and pancreas, suggesting its potential role in the management of diabetes.     

Aspirin resistance

Aspirin reduces the odds of serious atherothrombotic vascular events and death in a broad category of high risk patients by about one quarter. The term 'aspirin resistance' has been used to describe not only an absence of the expected pharmacologic effects of aspirin on platelets but also poor clinical outcomes, such as recurrent vascular events, in patients treated with aspirin. Various factors such as genetic, nonadherence, variable response to different doses, co-morbid conditions and drug interactions are responsible for aspirin resistance. Many methods, with their limitations, are available to measure the effects on platelets. Despite treatment failures, aspirin remains the single most cost-effective drug for the secondary prevention of atherothrombotic disease. To optimize its clinical effectiveness, clinicians should be aware of the potential causes of aspirin treatment failure, prescribe aspirin in appropriate doses, and encourage patients to take aspirin, stop smoking, and avoid regular use of NSAIDs.     

Evaluation of Lumbar Facet Joint Nerve Blocks in Managing Chronic Low Back Pain: A Randomized,Double-Blind,Controlled Trial with a 2-Year Follow-Up

Study Design: A randomized, double-blind, controlled trial.Objective: To determine the clinical effectiveness of therapeutic lumbar facet joint nerve blocks with or without steroids in managing chronic low back pain of facet joint origin.Summary of Background Data: Lumbar facet joints have been shown as the source of chronic pain in 21% to 41% of low back patients with an average prevalence of 31% utilizing controlled comparative local anesthetic blocks. Intraarticular injections, medial branch blocks, and radiofrequency neurotomy of lumbar facet joint nerves have been described in the alleviation of chronic low back pain of facet joint origin.Methods: The study included 120 patients with 60 patients in each group with local anesthetic alone or local anesthetic and steroids. The inclusion criteria was based upon a positive response to diagnostic controlled, comparative local anesthetic lumbar facet joint blocks.Outcome measures included the numeric rating scale (NRS), Oswestry Disability Index (ODI), opioid intake, and work status, at baseline, 3, 6, 12, 18, and 24 months.Results: Significant improvement with significant pain relief of ≥ 50% and functional improvement of ≥ 40% were observed in 85% in Group 1, and 90% in Group II, at 2-year follow-up.The patients in the study experienced significant pain relief for 82 to 84 weeks of 104 weeks, requiring approximately 5 to 6 treatments with an average relief of 19 weeks per episode of treatment.Conclusions: Therapeutic lumbar facet joint nerve blocks, with or without steroids, may provide a management option for chronic function-limiting low back pain of facet joint origin.     

The effect of black tea and caffeine on regional cerebral blood flow measured with arterial spin labeling

Black tea consumption has been shown to improve peripheral vascular function. Its effect on brain vasculature is unknown, though tea contains small amounts of caffeine, a psychoactive substance known to influence cerebral blood flow (CBF). We investigated the effects on CBF due to the intake of tea components in 20 healthy men in a double-blinded, randomized, placebo-controlled study. On separate days, subjects received a single dose of 184 mg caffeine (equivalent to one strong espresso coffee), 2,820 mg black tea solids containing 184 mg caffeine (equivalent to 6 cups of tea), 2,820 mg decaffeinated black tea solids, or placebo. The CBF and cerebrovascular reactivity (CVR) to hypercapnia were measured with arterial spin labeled magnetic resonance imaging (MRI) before and 2 hours after administration. We found a significant global reduction with caffeine (20%) and tea (21%) in gray matter CBF, with no effect of decaffeinated tea, suggesting that only caffeine influences CBF acutely. Voxelwise analysis revealed the effect of caffeine to be regionally specific. None of the interventions had an effect on CVR. Additional research is required to conclude on the physiologic relevance of these findings and the chronic effects of caffeine and tea intake on CBF.