Electrocardiographic changes during insulin-induced hypoglycemia in healthy subjects

Hypoglycemia is associated with alterations of the ECG, a phenomenon which might be used for the development of a hypoglycemia detection device. We investigated the reproducibility and magnitude of ECG alterations during insulin-induced hypoglycemia in nine healthy volunteers. The subjects were studied twice with an identical study protocol on two different study days. During hypoglycemia frequent ECG recordings were done with a conventional 12 lead ECG. S.c. injection of 0.15 U/kg of regular insulin induced a fourfold increase in insulinemia on both study days as well as a mean decline in blood glucose by 1.6 mmol/l to a minimum of 2.8 mmol/l within 60 min after injection. Blood potassium levels declined by a mean of 0.25 mmol/l to minimal values of 3.69 mmol/l. On both study days, a progressive flattening of the T-waves was observed during the experiments. R-waves remained constant leading to an increase in RT ratios by at least 50% in comparison to baseline values. These changes were most pronounced in leads I, V3, V5 and V6. The magnitude and reproducibility of the observed ECG changes during hypoglycemia may allow the development of a hypoglycemia detection device.     

Electrocardiographic changes in stroke patients without primary heart disease

OBJECTIVE: To examine the HIV seroconversion rate, risk factors for seroconversion, and changes in risk behavior over time in intravenous drug users (IVDU) in San Francisco, 1985-1990. DESIGN: Observational study. SETTING: All methadone maintenance and 21-day methadone detoxification programs in San Francisco. PARTICIPANTS: A total of 2351 heterosexual IVDU, of whom 681 were seronegative at first visit and seen at least twice ('repeaters'). MAIN OUTCOME MEASURES: HIV seroconversion rates, risk factors for seroconversion, and changes in behavior. RESULTS: The HIV seroconversion rate in repeaters was 1.9% per person-year (ppy) of follow-up [2.1% in women versus 1.7% in men (not significant); 4% in African Americans versus 1% in whites (P = 0.006); 3.9% ppy in the first third of the study, 1.2% in the second (P = 0.007), and 1.9% in the last (not significant)]. Risk factors for seroconversion were five or more sexual partners per year [hazard ratio (HR) = 2.6; P = 0.02], use of shooting gallery ever (HR = 2.9; P = 0.02), and less than 1 year (lifetime) in methadone maintenance (HR = 2.7; P = 0.02). Self-reported intravenous cocaine use fell from 33 to 15% over 5 years, shooting gallery use fell from 19 to 6%, and the proportion with five or more sexual partners fell from 25 to 10%. Bleach use rose to 75% of needle-sharers. CONCLUSIONS: The 1985-1990 HIV seroconversion rate in IVDU (1.9% ppy) was comparable to that in San Francisco cohorts of homosexual men (1.4% ppy). A decline in HIV seroconversion coincided with changes in risk behavior. Stable attendance of methadone maintenance was highly protective: the seroconversion rate in subjects with 1 year or more in methadone was 12% ppy.     

Histopathological changes in aluminium phosphide poisoning

A total of thirty cases of aluminium phosphide poisoning were studied for gross and microscopic changes in various organs of the body ie, lungs, liver, kidneys, heart, brain, stomach and adrenals. The histopathological changes revealed varying degrees of congestion, oedema and leucocytic infiltration, changes suggestive of cellular hypoxia. The most dramatic effects were produced in lungs, kidneys and adrenals.     

Toxicokinetics of acute strychnine poisoning

BACKGROUND: Strychnine competes with the inhibitory neurotransmitter glycine producing an excitatory state characterized clinically by hyperreflexia, severe muscle spasms, and convulsions. However, the kinetics after overdose have not been well described. Case Report: A 34 year-old male presented to the emergency department 20 minus after ingesting half of a 250-mL container of 2% strychnine sulfate (2.25 g). The reported lethal dose is 100-120 mg. He was alert and oriented and experiencing muscle spasms. His condition deteriorated prompting sedation, muscle paralysis, and tracheal intubation. He was given activated charcoal 100 g per nasogastric tube. He was admitted to intensive care where he was managed with diazepam, pentobarbital, and pancuronium. Despite mild rhabdomyolysis, he recovered and was extubated on day three. Although receiving prophylactic heparin therapy, a massive fatal pulmonary embolus ensued. Eighteen blood specimens for strychnine analysis were obtained from 20 minutes to 51 hours after ingestion. Serum concentrations were determined with gas chromatography-mass spectroscopy. Disappearance followed a first-order process with a t 1/2 of 16 hours (r, = 0.97). DISCUSSION: Our results confirm the findings of an earlier case report of 19 strychnine levels obtained between 4 and 19 hours which described first-order kinetics with a similar t 1/2 of 10 hours. CONCLUSION: Strychnine disappearance in this overdose was well described by a first-order process with a t 1/2 of 10-16 hours.     

Electrocardiographic changes in chest deformities. Apropos of 20 cases in black subjects

The objective of this study is to describe the electrocardiographic signs associated with certain chest deformities. This is a prospective, case-control study comparing 20 black subjects with chest deformity (11 cases of flat back syndrome, 5 cases of pigeon chest, 4 cases of funnel chest) with 20 age- and sex-matched healthy controls. Cardiac duplex ultrasound was performed for each individual to exclude associated heart disease. Atypical electrocardiographic signs were observed in 15 subjects with chest deformity versus only 3 in the control group. The anomalies observed consisted of signs of atrial or ventricular hypetrophy, right branch block, abnormalities of repolarization on the T wave or ST segment. Chest deformities are therefore associated with several electrical signs simulating most cardiac diseases. A good knowledge of these modifications should help to avoid the numerous diagnostic traps associated with these signs.     

HMPAO brain SPECT in acute carbon monoxide poisoning

Technetium-99m-hexamethylpropylene amine oxime (HMPAO) brain images with fanbeam SPECT, in combination with surface three-dimensional display, were used to detect basal ganglion and cerebral cortex anomalies in the acute phase of carbon monoxide (CO) poisoning. METHODS: Ten patients, aged 16-29 yr, with acute CO poisoning and no past history of neurologic disorders were enrolled in this study. After oxygen treatment, all 10 patients were investigated using 99mTc-HMPAO brain images with fanbeam SPECT and surface three-dimensional display. Meanwhile, 6 of 10 patients also received a brain CT scan. RESULTS: CT scan findings were negative in all 6 patients. Fanbeam SPECT demonstrated unilateral or bilateral hypoactivity of basal ganglia in 6 patients. Local hypoactivity anomalies were found in the brain cortex of 7 patients, using surface three-dimensional display of the brain. Only 2 of 10 patients had normal 99mTc-HMPAO brain images. CONCLUSION: This study suggests that, in comparison with traditional brain imaging techniques, 99mTc-HMPAO brain imaging with fanbeam SPECT in combination with surface three-dimensional display is a better tool for early detection of regional cerebral anomalies in acute CO poisoning.     

Accidental acute fatal sodium nitrite poisoning

OBJECTIVES: To report two patients who developed reactive arthritis in association with Staphylococcus aureus infection. METHODS: A review of the case notes of two patients. RESULTS: Two adult female patients have developed sterile arthritis in association with Staph aureus infection. The first patient has had two episodes of arthritis; the first followed olecranon bursitis, the second followed infection of a central venous catheter used for dialysis. The second patient developed sterile arthritis while being treated for pyomyositis. Both patients had a self limited arthritis and were HLA-B27 negative. CONCLUSION: Reactive arthritis may rarely follow Staph aureus infection. HLA-B27 negativity may be associated with a self limited arthritis in these cases.     

Acidosis and hyperlactatemia in acute sodium valproate poisoning

OBJECTIVES: We searched for signs of metabolic acidosis and associated hyperlactatemia in case of sodium valproate overdose. PATIENTS AND METHODS: A retrospective study was conducted in the toxicology intensive care unit at the Fernand Widal hospital from 1990 to 1995. Patients retained for study had sodium valproate levels above the therapeutic range (> 600 mumol/l). Data collected included past history, intubation for mechanical ventilation, administration of catecholamines and infusion of bicarbonate or sodium lactate, and blood pressure. Laboratory tests included serum sodium valproate, pH, PCO2, bicarbonate, anion balance and lactate. RESULTS: The study included 22 consecutive patients. None had a history of liver disease. Thirteen patients were intubated before admission to intensive care. Two received catecholamines. None of the patients received bicarbonate or sodium lactate. Mean blood pressure was 118 +/- 16 mmHg, mean serum sodium valproate was 2668 +/- 2437 mumol/l, mean pH was 7.41 +/- 0.08, mean PO2 35.6 +/- 8.0, mean anion imbalance 23.2 +/- 6.0 mmol/l and mean lactate 5.0 +/- 2.1 mmol/l. There was a significant correlation between lactase and pH (p < 0.003). CONCLUSION: We found metabolic acidosis with major anion imbalance and high lactate levels in patients with acute sodium valproate intoxication. Hyperlactatemia could be due to the direct effect of sodium valproate or to an unknown mechanism.     

Cerebrospinal fluid pressure changes after acute carbon monoxide poisoning and therapeutic effects of normobaric and hyperbaric oxygen in conscious rats

This study on conscious rats with occluded left carotid artery investigates the influence of cerebral edema after acute carbon monoxide (CO) poisoning on cerebrospinal fluid pressure (CSFp) and evaluates the therapeutic effectiveness of normobaric oxygen (NBO2) and hyperbaric oxygen (HBO2). The CSFp was continuously recorded via a cannula placed in the left cerebral ventricle before, during, and for up to 6 h after exposure to 0.27% CO for 1 h. A non-sustained small increase in the CSFp and identical degrees of hypoxemia, hypocapnia, arterial hypotension, and acidosis were found during the exposure in all rats. After the CO exposure, all non-edema control rats without carotid artery ligation (n = 7) recovered completely with normal CSFp, behavior, and brain water content. All untreated (n = 7) and NBO2-treated rats (n = 7) developed a severely increased CSFp (> 50 mmHg) with neurologic motor dysfunction, and died of a severely increased CSFp (> 100 mmHg) with considerable cerebellar herniation. Except in one rat, the CSFp did not reach a dangerous level (> 25 mmHg) after the HBO2 session (300 kPa O2 for 1 h, beginning at 20 min post CO). All HBO-treated rats (n = 7) survived with less neurologic motor dysfunction and less left hemispheric edema than those in untreated and NBO2-treated rats. The results demonstrated that the increase in the CSFp was related to the left hemispheric edema, and that the cerebellar herniation was the predominant cause of death after the CO exposure. HBO2, but not NBO2, prevented the severe increase in the CSFp and thus saved the life after the CO exposure.     

Distribution of probon in various organs in acute poisoning]

The amino acids composition of summary proteins in unground buckwheat of four common and promising varieties grown in the Ukraine was investigated by using ion-exchange chromatography with an automatic analyzor Hd-1200 E. Between individual varieties of buckweheat no essential differences in the amino acids content were in evidence. The total proteins of the buckwheat grit contain high quantities of lysine, treonine, leucine, glutamic acid and arginine. The amino acids score was instrumental in determining the biological value and in eliciting amino acids limiting this value in different grits. These data may be made use of in the practice of public catering for estimating formulae of meals prepared with grits differently combined with other products securing an improved amino acids composition of ready-to-eat meals.     

Morphological and histochemical changes in rat liver in subacute Phoschlor poisoning

Reserpine-pretreated or normal rabbit aortic strips (whose noradrenaline-metabolizing enzymes were inhibited by treatment with 0.5 mM pargyline and by the presence of 0.1 mM U-0521) were incubated with 1.18 muM labelled noradrenaline for 30 min. Subsequently, strips were either analysed or washed out with amine-free solution for 240 to 250 min. From the efflux curves the original distribution of radioactivity was estimated by compartmental analysis. 1. The accumulation of radioactivity in the strips was reduced by 30 muM cocaine to that observed for nerve-free strips. In reserpine-pretreated strips this was due to a partial reduction of the filling of comartment IV (characterized by a half time of efflux of 10 to 20 min; earlier evidence had already shown that part of this compartment is of neuronal origin; Hensling et al., 1976) and a pronounced decrease of the filling of compartment V (characterized by the longest half time). In normal strips the same changes were observed as well as pronounced reduction of the "bound fraction". Thus, cocaine reduced the filing of those compartments which had been identified as neuronal ones (Henseling et al., 1976). 2. When 30 muM cocaine was added to the wash out solution only, the neuronal efflux of radioactivity from reserpine-pretreated strips was accelerated, while the efflux from extraneuronal or extracellular compartments remained unaffected. This effect of cocaine was the same for (-)- and (+)noradrenaline, and its was not significaltly decreased when paired strips exposed to an inhibitor of extraneuronal uptake (86 muM corticosterone) throughout the experiment. In normal strips, cocaine had very little or no effect on the efflux of radioactivity. 3. The results are consistent with the view that cocaine impairs the influx of amine into the neurone, while block of re-uptake of unchanged amine is one of the determinants of its effect on the rate of efflux from the axoplasm. Comparison of efflux curves with corresponding relaxation curves (determined in the absence and presence of cocaine) indicates that, when both noradrenaline-metabolizing enzymes are inhibited, relaxation of the strips is accounted for by a) the efflux of unchanged amine from neuronal (and extraneuronal) stores and b) the sensitivity of the preparation to noradrenaline.