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Biomedical subjects

D Cohen

Publications and source records attributed to D Cohen.

At least 685 records · Page 38Linked to original sources
PubMed1981

High-dose methotrexate in osteogenic sarcoma.

From 1972 to 1979, high-dose methotrexate (HDMTX) and 3 adjuvant regimens were used at the Sidney Farber Cancer Institute and Children's Hospital Medical Center. In the first regiment, HDMTX was used alone; the second, HDMTX and adriamycin, and the third, weekly courses of HDMTX and combination. Actuarial disease-free survival achieved with these regimens in patient with local control of the primary lesion varied from 42 to 75% at 3 years. This compared favorably with historical control patients, of whom 50% were free of disease at 6 months and only 20% at 12 months. Among 41 patients with established pulmonary metastases, 14 were alive and free of disease from more than 4 to over 60 months. The most efficacious method of administering HDMTX was a weekly schedule which produced an overall response rate of 48% in the treatment of pulmonary metastases and primary tumor in patients previously not exposed to HDMTX. Urinary alkalinization was not a standard procedure, and investigations failed to demonstrate any significant effect of alkalinization on HDMTX pharmacokinetics.

Antineoplastic Agents↗
PubMed1981

Management of the patient and family coping with dementing illness.

The treatment objective of medical care for the demented patient is to maximize the level of functioning and the quality of life for both the patient and the family or caregivers. The majority of patients with dementia are in the community, and most families prefer to keep their relatives out of institutions as long as possible, usually until the family's resources are exhausted. The impact of dementing illness on family health can be severe, and family members can develop physical and psychiatric disorders. The physician can perform a range of important functions in the management of the patient and family and 12 are listed which may serve as a guide for clinical practice.

Dementia↗
PubMed1980

Suppression of the human allogenetic response in vitro with primed lymphocytes and suppressive supernates.

Human lymphocytes primed in vitro by allogeneic cells develop lymphocyte populations with different functions. Cells with a memory of the allogeneic contact and cytotoxic effectors have been identified previously. We now report on a third lymphocyte population generated by repeated in vitro sensitization. This is of suppressor lymphocytes that can inhibit the primary proliferation of unsensitized lymphocytes. Our experiments indicate that these human suppressor cells are most probably T lymphocytes, adherent to glass or nylon wool, and radioresistant. They derive from both the large blast cells and the small, nondividing lymphocytes that are observed on day 7 of the allogeneic response. The suppressor cells release suppressor factor(s) upon restimulation. Studies on the specificity of the suppression have shown that suppressor cells are specific to the HLA-DR antigens presented by stimulator lymphocytes and that they probably release the suppressor factor only when confronted with the specific HLA-DR antigen. However, when the suppressor factor is produced, the proliferative response to any stimulating cell is inhibited regardless of its HLA-DR antigens. On the other hand, the suppressor factor can only suppress the proliferation of lymphocytes from some individuals. This restriction suggests that suppression can only occur when the producer of the suppressor factor and the responding lymphocytes that are being tested, have some identities in common. No evidence in favor of an HLA-D restriction has been obtained so far.

Cell Adhesion↗
PubMed1980

Experience with day stay surgery.

Potential advantages of day stay surgery are cost saving, improved utilization of staff and hospital facilities, and reduction of stress for the paediatric patient and his family. The successful program requires careful case selection, full operating and anesthetic facilities and good follow-up. Day stay surgery was initiated at Royal Alexandra Hospital for Children in 1974. Experience is reviewed in relation to the total number and nature of surgical admissions and the daily utilisation of the facility. Utilization has markedly increased in the past 2 yr. Current practice is reviewed with regard to initial assessment, preparation for surgery and overall management during the day admission. Parental attitudes towards day stay surgery were evaluated indicating both the advantages and the problems encountered. These related mainly to insufficient information, transport difficulties and afternoon operations. Recommendations for improving the day stay service are discussed with special reference to: (1) communication with the parents as to adequate pre-operative explanation, revision of the day stay information pamphlet and improved distribution, and clear postoperative instructions, (2) the timing of operations, and (3) transport and parking facilities.

Ambulatory Surgical Procedures↗
PubMed1980

Magnetic fields produced by steady currents in the body.

The magnetic fields produced by naturally occurring steady currents in the body were measured by using a new magnetic gradiometer in a magnetically shielded room. A field of 0.1 micro G/cm with reproducible pattern was seen over the head and over the limbs, whereas the field over the torso proper was weaker (except over the abdomen). Most of the field over the head is produced by electrical sources associated with the hair follicles of the scalp; this field is produced only as a response to touching or pressing the scalp, in regions where the hair is dense. Most of the field over the limbs is produced by electrical sources associated with the muscles. The field over the forearm, studied in detail, was often present spontaneously; when absent, it could be induced by mild twisting and rubbing. On the basis of auxiliary experiments involving electrolytes, a general mechanism for generation of steady current in the body is suggested. In this mechanism, the steady current is generated by a nonclosed or a nonuniform polarized layer across an elongated semipermeable membrane such as a muscle fiber; the nonuniform polarization is due to a gradient of extracellular K+ along the membrane.

Abdomen↗
PubMed1980

In vitro cell-mediated cytotoxicity and antibody-dependent cellular cytotoxicity to the transmissible venereal tumor of the dog.

Cell-mediated immunity to the transmissible venereal tumor (TVT) of the dog was studied by use of a 51Cr release cytotoxicity assay. Peripheral blood lymphocytes (PBL) of dogs in which the TVT had regressed were shown to be cytotoxic to the tumor cells in contrast to PBL of normal dogs and animals during progressive tumor growth, which were not cytotoxic. In addition, sera of dogs in which the TVT had regressed could be demonstrated to mediate antibody-dependent cellular cytotoxicity (ADCC) with normal dog lymphocytes or cytotoxic PBL as effector cells. With cytotoxic lymphocytes, the ADCC effect could be observed in addition to the direct cytotoxic effect.

Animals↗
PubMed1980

Antinuclear antibodies in the cognitively impaired elderly.

The frequency of antinuclear antibodies was evaluated in older men and women aged 60 to 100 years with presumptive diagnoses of chronic brain syndrome or dementing illness. Thirteen per cent of the women and none of the men with organic brain syndrome had positive titers, compared to 3% for older men and women aged 60 to 89 years evaluated in a medical clinic population. It would appear to be valuable to evaluate the significance of antinuclear antibodies and other autoantibodies in the pathogenesis of dementing illness in the elderly.

Aged↗
PubMed1980

Feline leukemia in Israel: prevalence of antibody to feline oncornavirus-associated cell membrane antigen in stray cats.

Feline lymphoma was recorded for the first time in pet cats in Israel. Furthermore, a serological survey in urban stray cats was carried out to determine the prevalence of antibody to feline oncornavirus-associated cell membrane antigen (FOCMA). A total of 91 cats was tested and only 5 has antibody to FOCMA. Of these 5 positive cats, 4 originated from an area where a feline leukemia virus-positive cat had been detected prior to the survey. The prevalence of stray cats with antibody to FOCMA is lower in Israel than found in similar studies in the USA and Scotland.

Animals↗
PubMed1980

Serum immunoglobulins and cognitive status in the elderly: i. A population study.

Fifty-seven cognitively impaired elderly had significantly elevated serum IgG (P less than or equal to 0.005) and IgA (P less than or equal to 0.01) levels and similar IgM levels, compared to a population of 65 elderly matched for age and sex, who did not manifest cognitive impairment. These findings are compatible with a current hypothesis that immunological factors may be important in the cognitive disorders observed with increasing frequency among the aged.

Aged↗
PubMed1980

Phenformin increases insulin binding to human cultured breast cancer cells.

The effect of the hypoglycemic biguanide, phenformin, on the binding of insulin to MCF-7 cells, an in vitro line derived from a human breast cancer, has been investigated. Cells incubated for 24 h in the presence of 1.0 micrograms/ml of phenformin bound 62.2 +/- 8.1% (mean +/- SE) more 125I-insulin than did controls. The phenformin effect was dose-dependent over the concentration range of 0.1 micrograms/ml to 10.0 micrograms/ml. The increased binding was due to an increase in receptor number without a change in binding affinity. This demonstration of increased receptor number in response to phenformin exposure provides support for the hypothesis that one action of phenformin is to enhance tissue sensitivity to insulin.

Breast Neoplasms↗
PubMed1980

Different stimulating capacity of B and T lymphocytes in primary and secondary allogeneic reactions: cellular detection of HLA-D products on T lymphocytes.

The present study was undertaken to define the best way to produce and to test primed lymphocyte typing (PLT) cells using B- and T-enriched lymphocyte suspensions. Intrafamilial PLT cells were produced with primed unseparated and T purified lymphocytes against haplo-identical donors' T and B cells. These PLT cells were then restimulated with a panel of related or unrelated individuals' T and B cells and with allogeneic in vitro activated T cells. The best discrimination was obtained when PLT reagents, regardless of the production method, were restimulated by a B-enriched population of peripheral lymphocytes. Furthermore, the results have shown that enriched primed or unprimed T cell suspensions stimulated by enriched T lymphocytes did not give any proliferation. Experiments performed to explain the results led us to distinguish 2 different phenomena: in primary cultures, the addition of monocytes autologous to the responder cell restored the proliferation of enriched T cells stimulated by T lymphocytes. In secondary cultures, the addition of monocytes autologous to the PLT cell did not restore the proliferation of PLT lymphocytes stimulated by enriched T cells. This was shown to be due to the lack of Dr antigen on the stimulating cell: if allogeneically activated T cells were used as stimulating lymphocytes, a DR-specific proliferative response appeared. This correlates with serologic findings were DR determinants are found on activated T cells and not on unprimed T lymphocytes. However, this difference might be only quantitative, since peripheral lymphocytes could be primed by T cells and be DR specifically restimulated.

B-Lymphocytes↗
PubMed1980

The relationship of age, anxiety, and serum immunoglobulins with crystallized and fluid intelligence.

Serum immunoglobulin concentrations (IgG, IgA, and IgM), cognitive performance (crystallized and fluid intelligence), and self-reports of anxiety were evaluated in 24 men and women 60-75 years, and 50 men and women, 30-45 years. Trait anxiety was an important factor relating to performance differences between the young and old on crystallized and fluid subtests. IgM was inversely related to performance in the older age groups. Anxiety was not related to serum immunoglobulin levels.

Adult↗
PubMed1980

Diagnostic criteria for primary neuronal degeneration of the Alzheimer's type.

The diagnosis of patients presenting with memory or attentional deficits characteristic of dementia is a growing problem. Dementia may be symptomatic of a range of reversible medical and psychiatric conditions which appear to be indistinguishable from primary neuronal degeneration of the Alzheimer's type. While Alzheimer's disease is a neuropathological diagnosis, the importance of establishing a presumptive diagnosis which can be employed for investigational as well as clinical use is underscored. This paper proposes a diagnostic schema which reflects the current understanding of this disorder. There must be evidence of gradual progressive mental deterioration in attention, learning, memory, cognitive style, motivation, and higher order thinking. A comprehensive medical and psychiatric evaluation is obligatory to eliminate reversible physical illness, psychiatric disorder, or cerebrovascular condition as underlying causes of cognitive dysfunction.

Aged↗
PubMed1980

Trauma to major visceral veins: an underemphasized cause of accident mortality.

In the period 1970-1978, a mortality rate of 44% resulted in 45 patients who suffered major intra-abdominal venous injuries. An especially grave prognosis accompanied wounds to the inferior vena cava and the hepatic and portal venous systems. Management of damage to major veins presents several difficulties. Exposure is poor; veins tear easily when clamped or sutured; exsanguination can occur as rapidly as with arterial trauma; because of low intraluminal pressure, postoperative chances of thrombosis and occlusion are high; veins (unlike arteries) have no intrinsic vasomotor capabilities to halt bleeding. Finally, the misconception persists that venous wounds are less serious than comparable arterial injuries. Simple pressure by packs or hand often controls bleeding: otherwise clamps, balloons, hemostats, or ligation can be selectively chosen. Our experience suggests that atrial-caval shunting without prior identification and control of the bleeding site is doomed to failure.

Abdomen↗