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Biomedical subjects

J B Block

Publications and source records attributed to J B Block.

At least 55 records · Page 3Linked to original sources
PubMed1975

Nonevaluable patients in clinical cancer research.

Analysis of controlled and uncontrolled published papers in clinical cancer therapy has revealed differences in patient data handling, which may reflect both the inherent biases of patient selection for uncontrolled studies and the primary purpose of such studies. A distinction between drug-data oriented research and patient oriented research was advanced to explain these results. If comparable results are to be developed, we urge controlled trials at all phases of treatment development.

Acute Disease↗
PubMed1975

High dose methotrexate as a preoperative adjuvant in the treatment of epidermoid carcinoma of the head and neck. A feasibility study and clinical trial.

Thirty patients with operable epidermoid carcinoma of the head and neck were treated with intravenous high dose methotrexate and leucovorin rescue prior to resection. Their clinical courses were compared with those of thirty randomly selected patients matched for tumors site and clinical stage who were treated by surgery alone. No medical or surgical complications associated with methotrexate were encountered. An objective decrease in tumor size (primary lesion or nodal metastases) was noted prior to resection in twenty-three patients (77 per cent). The number of recurrences in the two groups was similar. However, these was a significantly greater disease-free interval in the methotrexate-treated patients (p less than 0.05). No significant differences in survival have been noted to date between the two groups. In view of the absence of complications, the regressions in tumor size, and the increase in postoperative disease-free interval in this trial, evaluation as preoperative adjuvants of higher doses of methotrexate and of other chemotherapeutic agents in combination with methotrexate appears warranted.

Carcinoma, Squamous Cell↗
PubMed1975

Infection prevention in acute nonlymphocytic leukemia. Laminar air flow room reverse isolation with oral, nonabsorbable antibiotic prophylaxis.

Reverse isolation and prophylactic oral nonabsorbable antibiotics were evaluated among 64 consecutive noninfected adults with acute nonlymphocytic leukemia admitted for remission induction. Patients were randomly allocated to laminar air flow room reverse isolation with oral nonabsorbable antibiotics (LAF plus A), routine hospital ward care with antibiotics (W plus A), or ward care alone (W). The LAF plus A patients had a significantly decreased incidence of total infection, bacteremias, pneumonias, rectal abscesses, urinary tract infection, and pharyngitis. Infectious deaths were reduced in the LAF plus A group and the time to the first infection or to fatal infection was delayed. The W plus A patients who regularly ingested the antibiotics had a reduction in infections similar to that of the LAF plus A patients but those who could not tolerate the antibiotics had an incidence of infection comparable to the ward patients. The LAF plus A and the W plus A patients also had higher complete remission rates and longer median survival than the unprotected ward patients.

Acute Disease↗
PubMed1972

Impaired lymphocyte transformation in intestinal lymphangiectasia: evidence for at least two functionally distinct lymphocyte populations in man.

Intestinal lymphangiectasia is a disease characterized by hypoproteinemia and edema resulting from protein-losing gastroenteropathy secondary to abnormal intestinal lymphatics. Immunologic abnormalities associated with this disease include hypogammaglobulinemia, lymphocytopenia, skin anergy, and impaired allograft rejection. In the present study, the in vitro blastogenic transformation of lymphocytes from 12 patients with intestinal lymphangiectasia was assessed in order to gain insight into the mechanism of the cellular immune defect in this disease. Peripheral blood lymphocytes from patients with intestinal lymphagiectasia showed impaired in vitro transformation to nonspecific mitogens, specific antigens, and allogeneic cells when compared to equal numbers of cells from normal individuals. Patients with the most deficient in vitro reactivity tended to have the lowest serum albumin concentration and the lowest absolute lymphocyte count. Lymphocytes obtained from chylous effusions in each of the four patients studied transformed more vigorously than peripheral blood cells from the same patients. These results may be explained by the loss of recirculating, long-lived lymphocytes into the gastrointestinal tract, resulting in a relative depletion of the population of lymphocytes necessary for in vitro blast transformation. This disease thus represents a clinical analogue of animals with experimental thoracic duct drainage, and provides evidence for the existence, in man, of two functionally distinct lymphocyte populations. In addition, these findings establish a new mechanism of impaired delayed hypersensitivity and defective in vitro lymphocyte transformation, i.e. the gastrointestinal loss and consequent depletion of the long-lived, recirculating population of lymphocytes from the peripheral lymphocyte pool.

Adolescent↗