Search PubMed⌕ Search

Biomedical subjects

S Sofer

Publications and source records attributed to S Sofer.

At least 55 records · Page 3Linked to original sources
PubMed1993

Fatal paraphenylenediamine (hair dye) intoxication in a child resembling Ludwig's angina.

A 6 year-old child with paraphenylenediamine intoxication is presented. The patient suffered from sore throat, cough, and anorexia, followed by severe dyspnea caused by edema of the tongue, pharynx, and neck, renal failure, and metabolic acidosis. A presumptive diagnosis of Ludwig's angina, a severe anaerobic infection of the sublingual neck space, was entertained. Despite institution of vigorous supportive therapy and administration of antibiotics, the child developed irreversible ventricular fibrillation and died eight hours after admission. Two days after the patient's death, his father recalled that the child and his dog ingested an unidentified substance shortly before the onset of the child's symptoms. The dog died within a few hours. The substance was identified as the hair dye, paraphenylenediamine.

Angina Pectoris↗
PubMed1992

Fatal familial infantile glycogen storage disease: multisystem phosphofructokinase deficiency.

An infant girl of consanguinous Bedouin parents suffered from fatal early onset of progressive generalized muscle weakness. Her older brother suffered from similar weakness and cardiomyopathy, which led to his death at the age of 21 months. A muscle biopsy performed on the propositus at the age of 9 months was PAS-negative, and showed nonspecific myopathic changes. A second muscle biopsy, performed at 21 months of age, a few days before her death, and postmortem study of heart and liver, disclosed excessive extralysosomal glycogen storage and reduced phosphofructokinase-1 (PFK-1) activity. Because the genes encoded for PFK-1 in liver and muscle are located on separate chromosomes, the reduced enzyme activity in both tissues could not be related to a single mutation for this enzyme. Activity of 6-phosphofructose-2-kinase (PFK-2), a recently discovered physiological activator to all PFK-1 isozymes, was normal in the liver. The possibility that this multisystem PFK-1 deficiency may be related to the absence of a yet unknown activator, common to all PFK-1 isozymes, is discussed.

Biopsy↗
PubMed1992

Renin and aldosterone levels and hypertension following envenomation in humans by the yellow scorpion Leiurus quinquestriatus.

Renin activity and aldosterone blood levels were measured in ten patients following scorpion envenomation by the scorpion Leiurus quinquestriatus. All patients were hypertensive on admission, with clinical signs of systemic intoxication. The blood renin and aldosterone levels were elevated in all ten patients. The observation of high blood pressure and elevated levels of renin suggests that in addition to increased circulating catecholamines following scorpion envenomation, sympathetically induced renin release may play an important role in the pathogenesis of hypertension. This observation re-emphasizes the importance of afterload reduction in the treatment of the cardiovascular manifestations of scorpion envenomation.

Adult↗
PubMed1992

The cardiovascular system after scorpion envenomation. A review.

Scorpion envenomation is a common medical problem and life hazard in many countries of the world. Scientific investigations have addressed the interrelationship between the stimulatory effects of the venom on the autonomic nervous system and adrenals and the subsequent effects of released transmitters on the cardiovascular system. A number of clinical cardiovascular syndromes may dominate the initial clinical presentation after envenomation: the syndromes usually vary with the age of the victim, the size of the offender and the season. Central nervous system dysfunction is seen in children but rarely observed in adults; if accompanied by severe hypertension the clinical picture is consistent with acute hypertensive encephalopathy. Heart failure, pulmonary edema or a shock-like syndrome has been observed in 25% and hypertension in 30% to 77% of our patients. The electrocardiographic abnormalities recorded in the majority of the patients after envenomation include an "acute myocardial infarction-like pattern." Rhythm disturbances are frequent but conduction abnormalities are rare. Echocardiographic, radionuclide and experimental hemodynamic observations have provided evidence that heart failure and pulmonary edema after envenomation are multifactorial with diminished systolic performance following the initially increased left ventricular contractility and decreased ventricular diastolic compliance. Clinical laboratory data reporting increased catecholamine metabolite excretion and elevated plasma renin and aldosterone are consistent with the stimulatory effects of the venom on the autonomic nervous system. Treatment, including our experience with vasodilators and calcium channel blockers, is reviewed.

Angiography↗
PubMed1992

Acute pancreatitis in children with anticholinesterase insecticide intoxication.

Gastrointestinal symptoms are commonly seen in anticholinesterase insecticide intoxication. A few studies in adults have demonstrated some evidence for pancreatic damage in this poisoning. To see whether this association exists also in children, we conducted a prospective study in 17 consecutive children with typical organophosphate and carbamate poisoning. On admission and following recovery, serum amylase, immunoreactive trypsin, glucose, calcium, urea, creatinine, and arterial blood gas values were determined and compared with those of age-matched control subjects. Acute pancreatitis was diagnosed in 5 subjects. They demonstrated significantly elevated (greater than mean + 2 SD) serum levels of both immunoreactive trypsin (914.0 +/- 317.4 ng/mL, 159.9 +/- 36.4 ng/mL, and 169.7 +/- 41.2 ng/mL, respectively; P less than .01) and amylase (448.0 +/- 264.4 U/L, 152.8 +/- 90.9 U/L, and 56.8 +/- 26.3 U/L, respectively; P less than .001; n = 4), compared with other patients and control subjects. Gastrointestinal symptoms were noted in all 5 subjects, with severe abdominal pain in 2. Such symptoms were evident in only 41% of the other 12 patients. Serum glucose levels were significantly elevated in these subjects compared with others (389.0 +/- 66.2 mg/100 mL vs 180.4 +/- 72.3 mg/100 mL; P less than .01). None had hypocalcemia, renal dysfunction, or acidosis. All had complete recovery. It is concluded that acute pancreatitis is probably not rare in children with anticholinesterase insecticide poisoning. This may contribute to the development of gastrointestinal symptoms and hyperglycemia often observed in these patients.

Abdominal Pain↗
PubMed1991

[Henbane (Hyoscyamus reticulatus) poisoning in children in the Negev].

During 1984-1989, 19 Bedouin children, 4-8 years old, were hospitalized because of henbane plant (Hyoscyamus reticulatus) poisoning. There were 14 cases in the autumn, 3 in the spring and 2 in the summer. The most prominent signs were altered state of consciousness (including deep coma in 3) and flushed dry, warm skin in all. Pupils were dilated in 18 of the 19 and restlessness and hallucinations were present in 17. Less common were vomiting, increased tendon reflexes, convulsions, involuntary movements, ataxia, hypertension, hyperpyrexia and tachycardia. Therapy included intravenous physostigmine in 7 and sedatives (diazepam and triclofos) in 6. All were free of symptoms within 24 hours of admission. Henbane may grow as an annual or biennial. Renewed growth of leaf rosettes occurs before the first rains and they attract attention in the fields. The parts of the plant eaten by most of the children were the roots, which are easily mistaken for the edible roots of other plants. The main alkaloids in henbane are atropine (hyoscyamine) and scopolamine (hyoscine) which explains the clinical picture of mixed stimulation and depression of the brain. Educational measures should be undertaken to prevent poisoning of Bedouin children by eating such plants.

Child↗
PubMed1991

Design considerations for an immobilized cell bioreactor operating in a batch recirculation mode.

Immobilizing microbial cells and enzymes used in biological and biochemical processes is advantageous and has been a subject of intensive study in recent years. Successful implementation of this technology requires complete understanding of physical, chemical and biological parameters which influence the performance of such a system. This paper focuses on a few basic design considerations which are essential to the design and operation of immobilized cell bioreactors. A process using microorganisms entrapped in calcium alginate gel as a biocatalyst is considered. This system is used to biodegrade the organic compound, phenol. A batch reactor operated in a recirculation mode is used, and parameters like concentration of dissolved oxygen, concentration of the organic compound, bead size, biomass loading and the flow rate are studied. The bioreactor can be operated within many operating windows where one of the above parameters may be rate limiting. With the help of conceptual and experimental data, the influence of the above parameters on the reaction rates is discussed.

Alginates↗
PubMed1991

Acute pancreatitis in children following envenomation by the yellow scorpion Leiurus quinquestriatus.

Plasma immunoreactive cationic trypsin (ICT), which is a specific and highly sensitive indicator of pancreatic injury, was measured in 14 children with signs of systemic envenomation following a sting by the scorpion Leiurus quinquestriatus. High ICT levels were found in 13 children (93%), indicating that acute pancreatitis is a common complication of envenomation by this scorpion. The pancreatitis may account for the abdominal pain and vomiting commonly seen in scorpion envenomation and may also contribute to the agitation and discomfort noted in young children.

Acute Disease↗
PubMed1991

Myocardial injury without heart failure following envenomation by the scorpion Leiurus quinquestriatus in children.

The enzymatic activity of creatine kinase-MB isoenzyme (CK-MB), a sensitive and specific marker of myocardial damage, was measured in 32 children following scorpion envenomation. CK-MB activity, total creatine phosphokinase (CPK) and serum glutamine oxalacetic transaminase (SGOT) levels were examined for relationship with electrocardiographic (ECG) results and the clinical state of the children. Twenty-seven out of the 32 children had signs of systemic intoxication ("symptomatic" cases), while the other five children had only local signs ("asymptomatic" cases). Thirteen out of the 27 symptomatic children had enzymatic myocardial involvement characterized by high total CPK level, elevated CK-MB level and a CK-MB/CK ratio exceeding 6%. Six of these 13 children had ECG changes consistent with myocardial damage, and only one child had clinical signs of myocardial injury. None of the asymptomatic children, nor five healthy control children, had any evidence of myocardial damage as judged by CK-MB levels, clinical signs and ECG. Our study suggests that CK-MB activity is specific and highly sensitive in detecting myocardial damage in children following scorpion envenomation, and appears superior to ECG and clinical parameters. We speculate that the myocardial lesions are too small to cause heart failure in most cases, but they may account for the cardiovascular changes frequently seen in scorpion envenomation.

Adolescent↗
PubMed1991

Traumatic atlanto-occipital dislocation in children: review and report of five cases.

Traumatic atlanto-occipital dislocation has usually been considered incompatible with life. However, reports on survivors stress the need for early clinical diagnosis of this condition, particularly in the context of multiple trauma, in order to avoid life-threatening diagnostic manipulations and to provide adequate treatment. Five instances of atlanto-occipital dislocation in children observed during the last two years prompted this report, since four of them survived only temporarily. The radiologic and computed tomographic (CT) findings have been reevaluated. Use of metrizamide CT is advised in clinically suspected cases with inconclusive radiologic workup.

Atlanto-Occipital Joint↗
PubMed1991

Vibration analysis of a blood processor centrifuge with anti-twister mechanism.

This paper deals with the vibration analysis of a blood processor centrifuge with an anti-twister mechanism. Blood processors that employ anti-twister mechanisms are becoming increasingly popular because they cause relatively less damage to the blood than the conventional ones, which employ rotating seals. Knowledge of the vibration response of the device in its operating regime is important for trouble-free operation. A simple, three-degree-of-freedom, lumped-parameter, torsional-mode model is presented here. This model was used to analyse an existing blood processor. On comparing experimental and analytical values, it was found that the fundamental frequency as predicted analytically is within 19 per cent of the experimental value; the predicted second harmonic is about 28 per cent higher than the experimental one. Thus the proposed model predicts the fundamental frequency with reasonable accuracy. In design, the goal is to keep the operating frequency of the device sufficiently above the fundamental frequency to avoid resonance problems.

Cell Separation↗
PubMed1991

[Bacterial tracheitis in children].

Bacterial tracheitis (BT) was found in 10 of 748 children (1.3%) admitted with croup during 1983-1990. 9.9% of all the 748 croup cases seen (74) were admitted to the pediatric intensive care unit (PICU) and 16 of the 74 required intubation. 10 of those intubated (62.5%) were found to have BT and had typical features of croup, including inspiratory stridor, hoarseness and cough. Airway obstruction resulted mainly from accumulated tracheal pus. After endotracheal intubation all required frequent suctioning of thick purulent secretions. In 2 children causative microorganisms were cultured from the blood, and in all 10 from the tracheal pus. All children were given antibiotic therapy but a 7 month-old girl died of secondary complications (respiratory syncytial virus infection, pneumonia and adult respiratory distress syndrome). The others recovered and were discharged from the PICU within 3-14 days. BT should be suspected when tracheal intubation is required in croup. In such cases close monitoring in a PICU and frequent tracheal suctioning after intubation is necessary; antibiotic therapy should be considered.

Anti-Bacterial Agents↗
PubMed1990

Echocardiographic and radionuclide angiographic observations following scorpion envenomation by Leiurus quinquestriatus.

The echocardiographic and radionuclide angiographic abnormalities in children after scorpion envenomation with L. quinquestriatus, were evaluated. Five children were severely hypertensive, one of them in respiratory failure and another had pulmonary edema. The results revealed poor global contractility 12-15 hr after the sting in three patients. The radionuclide angiograms also revealed poor contractility with low ejection fraction. There was enzymatic evidence of myocardial damage. The changes observed in the echocardiograms and radionuclide angiograms were attributed to catecholamine induced myocardial ischemia. The abnormalities observed suggest that systolic dysfunction plays a role in the pathogenesis of heart failure in scorpion envenomation, in addition to a decrease of left ventricular compliance and increased impedance to left ventricular emptying. The beneficial effects of nifedipine in hypertension and other cardiovascular manifestations justify the routine use of afterload reduction in children with cardiovascular manifestations after scorpion envenomation.

Adolescent↗
PubMed1990

Cat-scratch encephalopathy presenting as status epilepticus and lymphadenitis.

A five-year-old male was admitted to the hospital with generalized seizures. Enlarged lymph nodes raised the suspicion of cat-scratch disease. The diagnosis was confirmed by a positive history of a cat bite, typical histopathologic findings in the biopsy of the lymph nodes, and a positive skin test. Brain CT scan and LP were repeatedly normal. The clinical course was remarkable for recurrent episodes of status epilepticus refractory to usual anticonvulsant therapy and prolonged encephalopathy consisting of mental confusion, hemiparesis, tremor, chorea, and vomiting. All neurologic symptoms gradually resolved within nine months, without sequelae. Cat-scratch encephalopathy should be suspected in a child presenting with status epilepticus and enlarged lymph nodes. Aggressive and prolonged anticonvulsant therapy is strongly recommended.

Brain Diseases↗
PubMed1990

Risk factors for infantile hypothermia in early neonatal life.

Hypothermia in infancy is not uncommon among the low socioeconomic population in various parts of the world. It is prevalent in Israel and is associated with severe morbidity and mortality. We tried to identify neonates at risk among the population of the Negev district of Israel. Ninety-one infant hospitalized with infantile hypothermia (IH) during the years 1974 to 1981 were identified. The neonates belonged to two distinct ethnic groups, Bedouins and Jews, and were compared with 120 healthy controls of similar background. Our data show that premature infants and babies with low birth weight born during the cold season to young (inexperienced) mothers of lower socioeconomic strata and who sustained perinatal morbidity are at risk for IH. It is suggested that parents of infants at risk should be approached while the baby is till in the nursery, be advised about the possibility of hypothermia, and institute the appropriate preventive measures.

Birth Weight↗