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I Yaniv

Publications and source records attributed to I Yaniv.

85 records · Page 5Linked to original sources
PubMed1988

Heterogeneity of childhood acute lymphoblastic leukemia (ALL): monoclonal antibodies phenotyping and induction of differentiation in vitro.

Fifty-eight pediatric patients with non-T acute lymphoblastic leukemia (ALL) were diagnosed and evaluated at the Sambur Center of Pediatric Hematology Oncology. At least six subtypes of non-T ALLs were identified, corresponding to the various stages of B-cell differentiation, by utilizing an extensive panel of monoclonal antibodies directed against T- B- and myeloid-cell differentiation antigens. Moreover, leukemic cells expressing the phenotype of early B cells could be driven to differentiate along the B- cell lineage to express CALLA and BL antigens and cytoplasmic and/or surface immunoglobulins (IgM). A unique phenotype of non-T ALL was also identified. These leukemic cells expressed B cell antigen exclusively, i.e., HLA/DR and B4 (CD19). Myeloid-cell antigens, however, were expressed on these cells spontaneously after a 24-hour incubation in culture medium in vitro. In addition, leukemic cells of four patients with a phenotype of HLA/DR, CD19, and CD10 expressed antigens of the T-cell lineage: CD7 (3AI) and CD2 (leu 5), and/or of the myeloid cell lineage (My7). These results provide confirming evidence for the wide scope of the heterogeneity of ALL. It stresses the validity of accurate classification of leukemia to identify biologically and clinically unique subtypes of ALL, which bears specific prognostic parameters; and designates therapeutic protocols.

Antibodies, Monoclonal↗
PubMed1987

Activation and metacognition of inaccessible stored information: potential bases for incubation effects in problem solving.

Two experiments were conducted with a hybrid procedure that involved a battery of indirect criterion tests designed to study the activation and metacognition of inaccessible stored information. In each experiment, subjects first attempted to recall some rare target words in response to a series of definitions meant to cue retrieval from long-term semantic memory. For the words that could not be recalled initially, the subjects rated their feelings of knowing. They then performed a lexical-decision task in which the target words and other control words were presented. Reaction times were measured as a function of the feeling-of-knowing ratings and the length of the interval between the initial exposure to the definitions and the subsequent lexical decisions. Faster decisions occurred for the target words than for the controls, especially when strong feelings of knowing had been expressed about the targets. Similar facilitation was obtained in a subsequent old-new recognition task. It appears that unsuccessful attempts to retrieve inaccessible stored information prime the later recognition of the information through a process of spreading activation. Such activation may sensitize people to future occurrences of stimulus inputs needed for insightful solutions of semantically rich problems.

Cognition↗
PubMed1984

Factor XI deficiency in an Arab Moslem family in Israel.

An arab moslem family with members affected by PTA deficiency is described. 3 children were found to have major deficiency, factor XI procoagulant activity being 3, 3 and 4 units/dl. 8 members, including parents, paternal grandparents and 4 siblings, were found to have minor deficiency of factor XI (40 to 68 units/dl). Assays of immunoreactive material in 4 members corresponded to the level of procoagulant activity. In this family, gene expression is autosomal recessive. The only bleeding episode reported was haematuria in the propositus. No other spontaneous, post-trauma or post-operative bleeding was noted. The PTA deficiency was reported until now, mainly in ashkenazi jews. This family is the first case of PTA deficiency ever reported in arab moslems.

Adult↗
PubMedDate not supplied

Therapeutic monitoring of busulfan in pediatric bone marrow transplantation.

The aim of this study was to describe busulfan disposition in a pediatric population who underwent bone marrow transplantation (BMT). Busulfan administered dose was 1 mg/kg every 6 h for 4 days. Plasma determinations were performed after the first dosing at 0, 15, 30, 60, 90, 120, 180, 240, 300, and 360 min. A noncompartment analysis model for extravascular absorption was used for the pharmacokinetic analysis. To obtain the area under the concentration-time curve (AUC) within the "therapeutic window" of 1,000-1,200 microM x minutes a busulfan dose adjustment Was performed at the fourth dose. Forty-five busulfan pharmacokinetic analyses were performed in 34 children. Eleven children had their dose adjusted [1.19 +/- 0.14) mg/kg] at the fourth dose and the AUC was monitored at the fifth one. The mean AUC +/- SD after the fifth dose (998.1 +/- 189.2 microM x min) was different (p = .006)from that after the first dose (1 mg/kg) (687.63 +/- 166.43 microM x min). Six children had their first AUC into the "therapeutic window," 17 children had their dose adjusted [1.2 (+/- 0.22) mg/kg], but the "adjusted" AUC was not available. These data suggest that it may be reasonable to recommend a busulfan dose of 1.2 mg/kg to achieve the accepted therapeutic target in children undergoing BMT.

Animals↗
PubMedDate not supplied

A plea for incidental appendectomy in pediatric patients with malignancy.

The evaluation of right lower quadrant (RLQ) abdominal pain in pediatric patients with malignancy can be difficult. However, since the mortality rate from peritoneal infections in these patients is very high, the differential diagnosis of RLQ peritoneal irritation, mainly of acute appendicitis (AA) versus neutropenic enterocolitis (NE), is crucial. Three cases of pediatric patients with malignancy demonstrating these difficulties are represented to enlighten this problem. The first patient died of multiorgan failure after operation for perforated appendicitis without generalized peritonitis. The second had a severe life-threatening postoperative complication because of delayed diagnosis of acute appendicitis. The third patient with malignant pelvic spread, underwent an unnecessary abdominal exploration for suspected AA. In all these cases and probably in many others, the clinical outcome could have been different if a previous incidental appendectomy had been performed during the primary abdominal operation. Incidental appendectomy in oncologic patients is recommended to facilitate the differential diagnosis of RLQ pain and to exclude the diagnosis of AA.

Adolescent↗
PubMedDate not supplied

Childhood malignant thymoma: clinical, therapeutic, and immunohistochemical considerations.

Malignant thymomas are among the least common mediastinal tumors in the pediatric age group. Thymomas are considered malignant on the basis of macroscopic and microscopic invasiveness. As only 20 well-documented cases involving children have been reported in the literature, the pattern of responsiveness to therapy and the value of prognostic signs is obscure. Two cases of malignant pediatric thymomas are reported with pathognomonic histoimmunological features of aggressive thymoma. One was cured, with a follow-up of 70 months, and one died while on therapy. Analysis of the histological features and the immunoperoxidase staining displays the complexity of pediatric thymomas and the inability to prognosticate the outcome, respectively.

Adolescent↗