Volume 98  ·   Issue 06  ·  1985

The sutureless myocardial electrodes were implanted in 45 patients under local anesthesia by means of a limited thoracotomy through the transthoracic, subdiaphragmatic, or mediastinal routes. The myocardial leads were implanted in the left ventricle in 43 patients, in the right ventricle in 2, and in the atrium and ventricle in 2. Acute stimulation thresholds of the ventricle were measured at a pulse width of 0.5 ms. They ranged from 0.35 to 2.30 v (mean, 1.31±0.39 v). There were seven deaths. None of the deaths was related to pace-maker malfunction or electrode dislocation. One patient died one day post-implantation because of congestive heart failure. The advantages of the myocardial lead are surgery under direct vision, avoidance of radiation hazards, rather low stimulus threshold values, and stable pacing; but implantation of the myocardial electrode is not minor surgery and is associated with more non-pacemaker related complications than in sertion of transvenous electrodes.

This article reports the results of our determination of the cyclic nucleotide content of normal human skin. The cyclic AMP and cyclic GMP were 0.37 pmol/mg and 0.09 pmol/mg in the epidermis by wet weight and those in the dermis were 0.21 and 0.16. We stress the importance of limiting the thickness of the epidermal specimen to 0.1 mm, i.e. at the level of tips of the rete pegs, as this can limit the dermal content in the biopsy to 5-20% and does not influence the results of epidermal determination.

The results of our studies on cryopreservation of hematopoietic cells are reported. Freezing techniques, the effect of freezing rate and cryopreservative agent on the viability of bone marrow cells, and transplantation of cryopreserved bone marrow cells are described. The use of liquid nitrogen for the preservation of hematopoietic cells from different sources aids in the treatment of many organic .diseases including some malignant tumors.

During the past few years, it has been found that hemophiliacs suffer increasingly from AIDS, year to year. The first case of hemophiliac AIDS was reported in the winter of 1981, eight cases were reported in 1982 and 12 in 1983. We studied CMV, EBV, HTLV, and EA titers (see page 442) in hcmophiliacs, and found that hemophiliacs have much higher sensitivity to CMV and EBV than healthy controls (p<0.001). There was a significant difference between hemophiliacs without any AIDS symptoms and healithy men. The relationship between hemophiliacs and AIDS, and the reasons for hemophiliac acquiring AIDS are discussed.

Antibodies of cytomegalovirus (CMV), EB virus (EBV), human T-cell leukemia virus (HTLV) and EA of 73 homosexual men were tested. We found that the anti-CMV titer was significantly higher than that of the heterosexual control group (p<0.01). According to the symptoms and signs of acquired immunodeficiency syndrome (AIDS), the homosexuals were divided into healthy group, AIDS suspect group, and AIDS group. The anti-CMV antibody titer of each homosexuaI group showed significant differences from that of the controls. There was no difference in anti-HTLV titers in homosexuals and heterosexuals. The relationship between CMV and AIDS is discussed.

Dietary survey was carried out in October and November 1983 in 73 urban residents and 92 rural residents of Beijing from 1,594 persons, 25-64 years of age, with equal distribution in both sexes. The result showed that Beijing diet was higher in car-bohydrate and low in fat. The average daily salt in take was 14.2 g for urban residents and 15.7 g for rural residents, being about three times the estimated normal requirement. The proportion of polyunsaturated fat to saturated fat was 2.6:1, whereas the ideal proportion should be 1:1. Recommendation is made to reduce salt and animal fat intake in the Beijing diet.

Human bone marrow derived fibroblast colony-forming cells (F-CFU) and granulocytemacrophage colony-forming cells (GM-CFU) were simultaneously studied by liquid and semi-solid agar culture in 26 normal individuals and 33 hematological disorders in 13 patients with aplastic anemia, 9 acute non-lymphocytic leukemia, 6 acute lymphocytic leukemia and 5 malignant lymphoma. After 2 weeks of liquid culture, the growth rates and morphological characteristics of F-CFU from aplastic and leukemic mar rows did not differ markedly from the normal, except that patient groups show a wider range of colony number. The F-CFU incidence in patients with malignant lymphoma was lower than normal. Growth of GM-CFU from patients with aplastic anemia and leukemia was very poor. GM-CFU stimulation was not detected in any supernatants of F-CFU cultures. Confluent mono-layers of fibroblast cells grown from normal and aplastic marrow could directly stimulate the growth cf GM-CFU of normal marrow cells and little-GM-CFU was observed in areas lacking fibroblast cells. Fibroblast monolayers derived from acute leukemic marrows were poor stimulators of GM-CFU, this abnormality in interactions between stromal cells and hematopoietic progenitors may be important in the pathogenesis and clinical manifestation of leukemia. This study suggests that bone marrow fibroblast cells may directly affect hematopoietic stem cell proliferation and differentiation and supports the hypothesis that marrow fibrosis observed in patients with leukemia is of non-neoplastic origin and may be a reactive phenomenon. Analysis of the pathogenesis of aplastic patients with defective hematopoietic microenvironments may be possible.