The frequency of late reversibility in SPECT thallium-201 stress-redistribution studies.

The frequency of thallium-201 late reversibility was prospectively assessed in 118 patients who had stress-redistribution thallium-201 studies by single photon emission computed tomography (SPECT). These patients demonstrated two or more segments with nonreversible defects at 4 h imaging and underwent late (18 to 72 h) redistribution imaging. When the criterion of late reversibility was defined as greater than or equal to 1 segment with 4 h nonreversible defects demonstrating late reversibility, it was present in 62 (53%) of the 118 patients and 164 (22%) of 762 segments. When the criterion of greater than or equal to 2 segments was used, late reversibility was found in 41 (35%) of 118 patients and 143 (19%) of 762 segments. The frequency of detected reversible defects increased from 27% at 4 h imaging to 43% at combined 4 h and late imaging (p less than 0.0001) and was significantly increased in all myocardial regions. In comparing the efficacy of initial and late imaging alone versus performing initial, 4 h and late imaging for the identification of reversible defects, 421 (94%) of 449 segments classified as reversible by the latter protocol were also correctly identified by the early and late imaging only approach, with the remaining 6% (28 segments) comprising those segments demonstrating the reversible pattern at 4 h and the nonreversible pattern at late imaging. No major differences were noted with respect to clinical, stress electrocardiographic and scintigraphic variables between the 118 patients undergoing late imaging and 98 additional randomly selected patients with two or more nonreversible defects at 4 h, who did not have late imaging.(ABSTRACT TRUNCATED AT 250 WORDS)

Heparin and the phenotype of adult human vascular smooth muscle cells.

To study mechanisms controlling growth and phenotype in human vascular smooth muscle cells, we established culture conditions under which these cells proliferate rapidly and achieve life-spans of 50-60 population doublings. In medium containing heparin and heparin-binding growth factors, growth rate and life-span of human vascular smooth muscle cells increased more than 50% relative to cultures with neither supplement, and more than 20% compared to cultures supplemented only with heparin-binding growth factors. In contrast to observations made in rat vascular smooth muscle cells, smooth muscle-specific alpha-actin in the human cells was expressed only in the presence of heparin and colocalized with beta/gamma nonmuscle actins in stress fibers, not in adhesion plaques. Heparin, in the presence of heparin-binding growth factors, also caused more than 170% stimulation of tracer glucosamine incorporation into hyaluronic acid and a 7.5-fold increase in hyaluronic acid accumulation. In comparison, total sulfate incorporation into sulfated glycosaminoglycans increased by less than 40%. In light of our previous findings that heparin suppresses collagen gene expression, we conclude that heparin induces human vascular smooth muscle cells exposed to heparin-binding growth factors to remodel their extracellular matrix by altering the relative rates of hyaluronic acid (HA) and collagen synthesis. The resulting hyaluronic-acid-rich, collagen-poor matrix may enhance infiltration of CD44/hyaluronate-receptor-bearing T-lymphocytes and monocytes into the vascular wall, an early event in atherogenesis.

[An epidemiological survey of Clonorchiasis sinensis of 17 counties/cities of Hubei Province Research Institute for Parasitic Diseases].

An epidemiological survey was made on Clonorchiasis sinensis for the first time in 17 counties/cities of Hubei Province in 1988. The pathogen of clonorchiasis sinensis was found in 14 of the 17 counties/cities. Individual examination of some population was carried out and in 7 counties/cities, all the people were found to be infected. The infection rate was more than 10% in some of the places surveyed. Most of the cases were youngsters. The chief mode of infection was the habit of eating undercooked fish or holding fish in the mouth. These results showed that Clonorchiasis sinensis infection has been widespread in Hubei Province and in some areas the infection was serious attention should therefore be paid to its control without delay.

[An epidemiological study on clonorchiasis sinensis in Hubei Province].

An epidemiological study on clonorchiasis sinensis was conducted in 62 counties and cities in Hubei Province during 1987-1991, and clonorchis sinensis was identified in 52 counties and cities. Human population studies showed there were patients with clonorchiasis sinensis in 29 of 31 counties and cities investigated, with infection rates of 0.1%-16.2%. There were five species in two families of freshwater spiral shells as first intermediate host of clonorchis sinensis, 31 species in seven families of freshwater fish (with five species of fish newly discovered) and one species of freshwater shrimp as second intermediate host, and six species as reservoir host. Studies revealed holding small fish in the mouth and eating undercooked roasted fish were two major modes of transmission for clonorchiasis sinensis in the province.

[Evaluation of prevalent status of kala-azar in endemic area of Hubei Province].

OBJECTIVE: To identify the diagnosis of 14 cases with "kala-azar" previously reported in Hubei Province since 1989 and to evaluate the present status of the disease. METHODS: Bone marrow smear, immunological test (LDTand IFAT), mouse inoculation, fungi culture, vector (Phlebotomus) and reservoir host (dog) survey. RESULTS: Among the 14 cases, 12 cases were progressive disseminated histoplasmois, one was an imported case and another one was a remnant skin type "kala-azar" case. An immunological survey was conducted during 1997-1999 in 25 townships located in 23 counties of 9 prefectures and cities. A total of 13,890 persons had been examined by LDT, the positive rate was 0.07%, no positive case was found among the persons under 40 years of age. During the survey, 1,756 persons had been examined by IFAT, the results were negative. No Phlebotomus chinensis had been found in the surveyed area. A total of 302 dogs were examined, no sick dog had been found. CONCLUSION: Kala-azar has been eradicated in Hubei Province.