Biomedical subjects
Publications and source records attributed to A Lifshitz.
A patient with endocarditis caused by Corynebacterium CDC Group A-4 is described. This is the first case in the literature of endocarditis caused by this bacteria, and is unique in that the patient was immune competent and the infection occurred on a native valve. This case illustrates that corynebacteria cannot be considered a contaminant and that the exact pathogen should be identified.
The adhesive property of white blood cells is essential for a normal immune response. We examined the state of leukocyte adhesiveness/aggregation (LAA) in the peripheral blood of 31 mothers and their newborns by means of a direct slide test and found it to differ significantly, the respective per cents of aggregated leukocytes found in the peripheral blood being 15 +/- 6.4 and 5 +/- 3.3 (mean +/- SD). However, the particle concentration of white blood cells in the peripheral blood did not differ significantly (14.2 +/- 4.4 and 13.6 +/- x 10(9) l-1). By incubating a mother's plasma with her newborn's whole blood we could induce a significant (p less than 0.0001) increment in the state of LAA. We conclude that deficiency of a plasma factor that does not cross the placenta is responsible for the low LAA in the newborn's peripheral blood.
A cohort of children from Gaza was observed from birth to the age of one year. Blood specimens were collected at birth, before and after poliovirus vaccination and at one year of age. Poliovirus immunity before and after vaccination was assessed by ELISA and virus neutralization (NT). Positive predictive values for ELISA were between 81.5% and 90.8%. However, ELISA revealed a high frequency of false negatives, and unacceptably low negative predictive values between 28.6% and 55.4%. The history of poliovirus immunity in the cohort was further investigated by NT. A high level of seropositivity to poliovirus type 1 (PV-1) was found. In cord blood, 83.3% had a NT titre greater than or equal to 4 and 99.0% had a titre greater than or equal to 2. Similarly, by one year of age, 85.7% had a titre greater than or equal to 4 and 90.5% had a titre greater than or equal to 2. Seropositivity to PV-2 and PV-3 were slightly lower, ie 80.8% of children had a PV-2 titre greater than or equal to 4 and 75.4% had a PV-3 titre greater than or equal to 4. As for other developing areas, poliomyelitis eradication in Gaza will come about when universal vaccination fills all 'immunity gaps' and improved sanitation and housing reduces the endemicity of wild polioviruses.
45 patients with autosomal dominant polycystic kidney disease (APKD) were interviewed with regard to their knowledge about the familial nature of their disease. 22 patients (mean age up to 57 years) were treated with chronic dialysis, and 23 (mean age up to 49 years) had either normal serum creatinine or chronic renal failure without dialysis (serum creatinine range 1-7 mg/dl). Most of the patients knew the name and prognosis of their disease, but only 9% of them knew that half of their children might be at risk. Only 38% of the patients wanted to know that they had APKD before they had children and only 18% would not have had children if they had known beforehand that they were ill. 45% of the patients on dialysis and 78% of the patients not on dialysis would have had children in spite of their disease. The difference between the two groups is significant (p = 0.006). There was a correlation between the duration of follow-up of the patients and their children's knowledge (r = 0.38; p = 0.017). Genetic counseling in Israel is similar to that in other countries, but there is a large difference between the patients in Israel and others regarding their attitude towards childbearing. The finding of a linkage between a polymorphic region on chromosome 16 (3' HVR) to the locus of APKD makes a prenatal diagnosis of the disease possible. This could be a valuable tool for efficient counseling in the future.
We describe a 54-year-old man who suffered from familial Mediterranean fever, but the fever has been the only symptom during a 10-year period. During this period, results of laboratory tests and roentgenographic studies were negative. On the basis of these findings we propose that familial Mediterranean fever can be included in the causes of persistent fever in patients with long periods of fever.
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In order to determine if adult patients have reversible EEG abnormalities concurrent with fever, EEGs were recorded during fever in patients without neurologic disease or systemic disease capable of involving the central nervous system, and these were compared blindly with EEGs from the same patients taken at least 30 days after the febrile illness had disappeared. Fourteen patients completed the study, 10 men and 4 women, between the ages of 24 and 56 years, with fever secondary to localized infection. The global frequency of abnormal EEGs was high compared with the general population, since only 6 patients had both records completely normal; in 4 of these 6 cases during fever there were sleep patterns, mainly the first phase of slow wave sleep. Patients with localized abnormalities during fever showed the same abnormality in the EEG taken without fever, with two exceptions, one in which the abnormal finding disappeared and one in which another abnormality replaced the first one. Two patients had normal EEGs during fever and paroxysmal theta waves with predominance in their EEGs taken one month later. Fever in adults seems not to provoke rapidly reversible EEG changes. The high proportion of abnormal EEGs in these patients, and the appearance of new abnormalities in two cases after fever, deserves further research concerning the long-term effects of febrile illness on the EEG in adult patients.
Human epidermoid carcinoma A431 cell clones have been obtained whose growth is inhibited, stimulated, or unaffected by epidermal growth factor (EGF). In clones exhibiting each type of growth response, EGF induced similar morphologic changes consisting of aggregation of cells into dense clusters with baring of large areas of the culture dish. The similarity of the clones' morphologic responses, despite their differing growth responses, indicates that the effects of EGF on morphology are distinct from effects on growth. Cells whose growth was inhibited by EGF contained high numbers of EGF receptors, whereas the concentration of EGF receptors was reduced in cells whose growth was stimulated or unaffected by EGF. There were, however, no consistent differences in EGF receptor concentrations between stimulated or null clones. Cells that exhibited each type of growth response displayed similar rates of EGF binding to receptors, rates of internalization of EGF, and rates and extent of EGF-induced receptor down-regulation. Changes in EGF-stimulated tyrosine-specific protein kinase activity paralleled changes in EGF receptors, both between clones and upon down-regulation. These studies indicate that a reduction in the concentration of EGF receptors in A431 cells allows escape from the growth inhibitory effects of EGF, but suggest that the pattern of growth response depends on biochemical events subsequent to EGF-receptor metabolism and activation of tyrosine-specific protein kinase.
Epidermal growth factor (EGF), which stimulates tyrosine-specific protein kinase activity both in vivo and in vitro, inhibits proliferation of A431 human epidermoid carcinoma cells. After mutagenesis clonal cell lines that were resistant to the growth inhibitory effects of EGF were selected. All six variants examined contained decreased EGF-stimulated protein kinase. The number of EGF receptors in variant cells decreased in parallel with EGF-stimulated protein kinase activity so that the specific activity of EGF-stimulated protein kinase per EGF receptor remained constant in variant cell lines with up to tenfold reductions in both activities. This result suggests that both EGF binding and kinase activities reside in the same or closely coupled molecules. The effect of EGF on growth of two resistant variants was examined in detail. Clone 29 contains approximately 50% and clone 4 contains approximately 20% of the EGF-stimulated protein kinase activity of the parental A431 cell line. In serum-supplemented medium, EGF stimulated proliferation of clone 29 but did not affect growth of clone 4. In a 1:1 mixture of DME and F-12 medium without serum, EGF caused both clone 29 and clone 4 to grow as well as in 10% serum. These variants, which were selected for resistance to the growth inhibitory effects of EGF, thus exhibit a strong mitogenic response to EGF. This result suggests that resistance to the growth inhibitory effect of EGF may involve both a decrease in EGF-stimulated protein kinase and an alteration in the response pathway.
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A group of eight new long-chain aliphatic compounds recently isolated from the avocado and some derivatives thereof were tested for antibacterial activity on 13 different species of bacteria and a yeast. Some of these compounds inhibited the growth of microorganisms. 1,2,4-Trihydroxy-n-hepadeca-16-en was found to be the most active, inhibiting certain gram-positive bacteria at 4 mug/ml.
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This is a report of a case a larval granulomatosis associated with immunoblastic lymphadenopathy, corroborated by laboratory and histologic studies compatible with that. The etiopathogenesis, clinical picture and diagnosis of both diseases are commented, and the possible relationship between them is stressed.
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Clinical records of 160 patients admitted with fever of unclear origin were reviewed. Of them, all cases with fever of obscure origin (FOO) were selected based on the following criteria: at least two weeks with fever, with an oral temperature of 37.5 degrees C or more during hospitalization and whose clinical history, physical examination, hemocytologic data, erithrosedimentation rate, urinalysis, febrile tests, glutamic-piruvic transaminase, chest and abdomen radiographies were not suggestive of any specific diagnosis. 32 cases of FOO were found, but only the 30 which had been studied previously in another hospital were considered for analysis. Of these 30 patients, 18 were men and 12 women, with a mean age of 36.3 (range 19-64). Infectious diseases caused 40 percent and neoplastic disease 27 percent of cases. The single most frequent cause was non-Hodgkin lymphoma in four cases, followed by tuberculosis and Hodgkin's disease in three patients each. In four cases the cause of fever was not identified. Eleven patients required exploratory laparotomy; in nine of them it was usefull for diagnosis. Our results show a high proportion of neoplastic diseases, probably related with patient's selection and with intrinsic diagnostic difficulty of these kind of diseases.