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E Joseph

Publications and source records attributed to E Joseph.

51 records · Page 3Linked to original sources
PubMed1979

Cyclic AMP as a modulator of polarity in polycistronic transcriptional units.

The degree of natural polarity in the lactose and galactose operons of Escherichia coli is affected by adenosine 3',5'-cyclic monophosphate (cAMP). This effect, mediated by the cAMP receptor protein, is exerted at sites distinct from the promoter. Experiments performed with a mutant bearing a thermosensitive rho factor activity indicate that cAMP relieves polarity by interfering with transcription termination. Conflicting results in the literature concerning the role of cAMP receptor protein and cAMP in galactose operon expression can be reconciled by the findings that cAMP stimulates the expression of operator distal genes without significantly affecting the proximal genes. Therefore, it appears necessary to reevaluate the classification of the galactose operon as exhibiting cAMP-mediated catabolite repression at the level of transcription initiation.

Cyclic AMP↗
PubMed1979

Comments on the therapeutic action of psychoanalysis.

Together with some of the problems inherent in psychoanalysis as a therapy, I have described what the various schools of psychoanalysis hold in common--the basic assumptions, if you will, underlying any properly conducted psychoanalysis.

Awareness↗
PubMed1978

Formylation of initiator tRNA methionine in procaryotic protein synthesis: in vivo polarity in lactose operon expression.

Eucaryotic and procaryotic organisms differ in two aspects of their translation machinery: polycistronic messengers are expressed as a sequence of individual proteins only in procaryotes, and the initiation of protein synthesis proceeds with an initiator tRNA which is found to be modified (formylated) in procaryotes and not in eucaryotes. In the present study, we show that formylation is required in vivo for the coordinate expression of the Escherichia coli lactose operon. Our experiments are consistent with a translation mechanism using dissociated ribosomes at the 5' end of the mRNA in a reaction that is only weakly dependent on formylation at this initiation step; the ribosomes then travel along the messenger and can reinitiate after the intracistronic barrier without dissociation. This latter initiation step is strongly dependent on the level of formylation: a low level of the formyl group, obtained by the antifolic agent trimethoprim, induces a strong polarity in the expression of the lactose operon. There exist mutant strains in which this polarity is much less apparent than in the wild type. We show here that such is the case of rpsL mutants. Ribosomes mutated in the S12 protein (rpsL) are found to be much more easily dissociated than the wild type. This might explain why the expression of the lactose operon on rpsL strains remains coordinated when the intracellular level of formylation is decreased.

Acetyltransferases↗
PubMed1976

Protein calorie malnutrition and nutritional anaemia in Black pre-school children in a South African semirural community.

The incidence of nutritional anaemia and of protein calorie malnutrition in 119 randomly selected Black children living in the Muldersdrift area was studied. The ecology of nutritional problems in the community was also investigated. Major problems in the area were poor educational and medical facilities, a high childhood mortality rate and poor cash incomes. An important factor which influenced nutrition was large family size. The incidence of protein calorie malnutrition was 27,6% and of nutritional anaemia 13,3%. In the second year of life the incidence of anaemia was 27,3%. The main cause of anaemia was iron deficiency.

Black or African American↗
PubMedDate not supplied

Undiagnosed adult T-cell leukemia/lymphoma in central Brooklyn, NY.

We present a case, identified by surveillance for adult T-cell leukemia/lymphoma (ATL), who had initial symptoms not specifically related to ATL, and who would not have been identified as having ATL otherwise. A 51-year-old Trinidadian black woman was hospitalized for abdominal pain, nausea, and vomiting. Hematology and clinical chemistry revealed leukocytosis (19,600/mm3), an elevated lymphocyte percent (63%), and hypercalcemia (19.4 mg/dl). The patient was serologically confirmed with HTLV-I-associated ATL. Lymphoma was diagnosed at autopsy. This case is representative of ATL, which along with HTLV-I infection, may be emerging public health problems in urban communities of the northeast and southeast United States.

Blotting, Western↗
PubMedDate not supplied

Radioguided surgery for the ultrastaging of the patient with melanoma.

PURPOSE: Lymphatic mapping techniques have changed the standard of surgical care for the malignant melanoma population and are being investigated to improve the staging and decrease the morbidity of patients with all types of cancer. This study aimed to describe a combination of techniques and the use of multiple disciplines for accurately staging and treating patients with melanoma. MATERIALS AND METHODS: Over a 4-year period, 595 patients were studied using a protocol consisting of preoperative lymphoscintigraphy using filtered technetium sulfur colloid to define all regional basins at risk for metastatic disease, and intraoperative lymphatic mapping with a vital blue dye and radiocolloid to identify the node in the basin most at risk for metastases (the sentinel lymph node). Detailed pathological exam (serial sectioning, immunohistochemical staining, reverse transcriptase polymerase chain reaction [RT-PCR] analysis) of the sentinel lymph node was used to stage the melanoma patient. RESULTS: A combination of blue dye and radiocolloid intraoperative mapping resulted in a 98% success rate for the identification of the sentinel lymph node. Routine pathological examination identified 73.8% of the metastases. The remainder were detected with serial sectioning (7.8%) and immunohistochemical staining (18.4%). RT-PCR analysis based on a tyrosinase probe has upstaged 47% of the histologic sentinel lymph node-negative population. CONCLUSION: Lymphatic mapping technology provides accurate staging of the melanoma patient, at lower costs for the health care system and a lower morbidity for the patient.

Adolescent↗