Serum cholesterol concentration and coronary heart disease in population with low cholesterol concentrations

OBJECTIVE

To examine the relation between serum cholesterol concentration and mortality (from coronary heart disease and from other causes) below the range of cholesterol values generally seen in Western populations.

DESIGN

Prospective observational study based on 8-13 years of follow up of subjects in a population with low cholesterol concentrations.

SETTING

Urban Shanghai, China.

SUBJECTS

9021 Chinese men and women aged 35-64 at baseline.

MAIN OUTCOME MEASURE

Death from coronary heart disease and other causes.

RESULTS

The average serum cholesterol concentration was 4.2 mmol/l at baseline examination, and only 43 (7%) of the deaths that occurred during 8-13 years of follow up were attributed to coronary heart disease. There was a strongly positive, and apparently independent, relation between serum cholesterol concentration and death from coronary heart disease (z = 3.47, p less than 0.001), and within the range of usual serum cholesterol concentration studied (3.8-4.7 mmol/l) there was no evidence of any threshold. After appropriate adjustment for the regression dilution bias, a 4 (SD 1)% difference in usual cholesterol concentration was associated with a 21 (SD 6)% (95% confidence interval 9% to 35%) difference in mortality from coronary heart disease. There was no significant relation between serum cholesterol concentration and death from stroke or all types of cancer. The 79 deaths due to liver cancer or other chronic liver disease were inversely related to cholesterol concentration at baseline.

CONCLUSION

Blood cholesterol concentration was directly related to mortality from coronary heart disease even in those with what was, by Western standards, a "low" cholesterol concentration. There was no good evidence of an adverse effect of cholesterol on other causes of death.

Carboxy-terminal truncations of epidermal growth factor (EGF) receptor affect diverse EGF-induced cellular responses

The binding of epidermal growth factor (EGF) to its receptor induces tyrosine phosphorylation of phospholipase C gamma (PLC gamma), which appears to be necessary for its activation leading to phosphatidyl inositol (PI) hydrolysis. Moreover, EGF-receptor (EGF-R) activation and autophosphorylation results in binding of PLC gamma to the tyrosine phosphorylated carboxy-terminus of the receptor. To gain further insights into the mechanisms and interactions regulating these processes, we have analyzed transfected NIH-3T3 cells expressing two EGF-R carboxy-terminal deletion mutants (CD63 and CD126) with reduced capacity to stimulate PI hydrolysis, Ca2+ rises, and DNA synthesis. In fact, the CD126 mutant lacking 126 carboxy-terminal amino acids, including four tyrosine autophosphorylation sites, was unable to stimulate PI hydrolysis or Ca2+ rise in response to EGF. Surprisingly, EGF binding to the cell lines expressing CD63 or CD126 mutants was followed by similar stimulation of tyrosine phosphorylation of PLC gamma. Our results suggest that although necessary, tyrosine phosphorylation of PLC gamma may not be sufficient for stimulation and PI hydrolysis. It is clear, however, that the carboxy-terminal region of EGF-R is involved in regulation of interactions with cellular targets and therefore plays a crucial role in postreceptor signaling pathways.

Characterization of neuropeptide Y (NPY) receptors in human hippocampus

We identified a 50 kDa neuropeptide Y (NPY) receptor from human hippocampus by affinity labeling. NPY specific binding and labeling of the receptor were inhibited in parallel by increasing concentrations of unlabeled NPY (IC50 = 0.27 nM and 0.18 nM, respectively). Peptide YY (PYY), but none of the pancreatic polypeptides, was as effective as NPY in displacing [125I]NPY. NPY fragments inhibited binding with the rank order of potency: NPY greater than NPY13-36 greater than NPY20-36 greater than or equal to NPY18-36 greater than NPY1-36 free acid greater than or equal to NPY26-36. These results demonstrate that the human hippocampal NPY receptor is a 50 kDa protein fitting the classification of a Y2 receptor subtype.

Platelet-derived growth factor (PDGF)-induced disulfide-linked dimerization of PDGF receptor in living cells

It is well established that epidermal growth factor and platelet-derived growth factor (PDGF) are able to induce noncovalent dimerization of their surface receptors. It is thought that receptor dimerization plays an important role in activation of the tyrosine kinase function and in the process of receptor autophosphorylation. Here we show that the addition of either PDGF-BB or PDGF-AA to intact 3T3 cells induces formation of 400- and 430-kDa species, respectively, recognized by either anti-PDGF receptor antibodies or anti-phosphotyrosine antibodies. Interestingly, the 400- and the 430-kDa species are detected in nonreducing gels but not in reducing gels. Moreover, an alkylating agent, N-ethylmaleimide, inhibits PDGF-induced formation of high-molecular-mass species. Comparisons of V8 protease peptide maps of [35S]methionine-labeled PDGF receptors and high-molecular-mass proteins indicate that they represent dimers of PDGF receptors. It appears therefore that in addition to noncovalent dimerization, PDGF receptors undergo ligand-dependent disulfide-linked dimerization.

Expression of interleukin-6 and interleukin-6 receptor in Hodgkin's disease

Interleukin-6 (IL-6) is a multipotent lymphokine that can mediate differentiation of B cells into Ig-secreting cells, stimulate the growth of plasmacytomas, hybridomas, and T cells, and induce acute-phase proteins in liver cells. It has been suggested that IL-6 is involved in the pathogenesis of several diseases by autocrine or paracrine pathways. To examine whether IL-6 is possibly involved in the pathophysiology of Hodgkin's disease (HD), we analyzed the expression of IL-6 and IL-6 receptor mRNA and protein in cell lines and primary specimens from patients with HD. IL-6-specific transcripts were detected in three of six HD-derived cell lines by Northern blot analysis. In the culture supernatants of four HD-derived cell lines, IL-6 was detected by radioimmunoassay. Biologic activity of IL-6 was confirmed by proliferation of an IL-6-dependent cell line. In situ hybridization experiments showed IL-6-specific transcripts in Hodgkin (H) and Reed-Sternberg (RS) cells in primary tissues of two patients. In addition, mRNAs specific for the IL-6 receptor were detected in five HD-derived cell lines. Immunostaining experiments showed expression of IL-6 receptor molecules on H and RS cells in 8 of 16 cases with HD. Thus, our data suggest that IL-6 might be involved in the pathophysiology of HD.

Glycosaminoglycan and collagen metabolism in arylsulfatase B-deficient retinal pigment epithelium in vitro

Regional differences in retinal pigment epithelial (RPE) cell glycosaminoglycan (GAG) and collagen metabolism were studied using cells obtained from normal cats and those with deficient activity of arylsulfatase B (ASB), a lysosomal enzyme involved in GAG catabolism. Control and ASB-deficient RPE cultures initiated from superior equatorial (superior) and inferior equatorial (inferior) regions of the eye were radiolabeled for 72 hr with 35SO4, and GAGs from the media and cell layers were analyzed separately. In ASB-deficient RPE, there was an accumulation of dermatan/chondroitin sulfate in the cell layer of cultures initiated from the superior region of the eye but not in those initiated from the inferior region. This agrees with previous in situ and in vitro morphologic observations that accumulation of inclusions in ASB-deficient RPE was greater in the superior region of the eye than in the inferior region. By contrast, media from ASB-deficient cultures initiated from the inferior region of the eye contained much higher levels of radiolabeled dermatan/chondroitin sulfate than ASB-deficient cultures from the superior region or normal cultures. Increased GAG content in the media may result from increased secretion of proteoglycans, increased turnover of cell surface or extracellular matrix components, or extrusion of lysosomal contents. These results indicate that one or more of these mechanisms vary regionally throughout the eye in the RPE of ASB-deficient animals. Collagen production was determined in normal and ASB-deficient RPE cultures. In normal RPE, no differences in collagen synthesis were noted between the inferior and superior regions.(ABSTRACT TRUNCATED AT 250 WORDS)

Benextramine irreversibly inhibits [125I]neuropeptide Y affinity labeling of the Y2 binding protein in bovine hippocampus

Affinity labeling of iodinated neuropeptide Y (NPY) to bovine hippocampal binding proteins revealed that benextramine inhibited specific NPY labeling of the 50 kDa NPY binding protein (Y2 binding protein) in a dose-dependent manner (IC50 = 33 microM). Hippocampal membranes, which were pretreated with benextramine and washed, exhibited decreased [125I]NPY labeling of binding proteins in a similar dose-dependent manner. These findings demonstrate that benextramine irreversibly blocks specific NPY binding to the 50 kDa NPY Y2 binding protein.

[Karyotype analysis on bulbus Lilii]

A karyotype analysis has been made of the chromosome of five original species of Lilium. Lanceleaf Lily is the allotriploid.

Tyrosine phosphorylation of a common 57-kDa protein in growth factor-stimulated and -transformed cells

Protein tyrosine phosphorylation was studied in macrophages and fibroblasts to identify putative components of post-receptor mitogenic pathways that might be functionally conserved in different cell types. Nondenaturing conditions were established for the approximately quantitative recovery of anti-phosphotyrosine antibody (alpha PY)-reactive proteins from cells. A common, 57-kDa alpha PY-reactive protein was identified by V8 protease peptide mapping in colony-stimulating factor-1 (CSF-1)- or granulocyte-macrophage colony-stimulating factor (GM-CSF)-stimulated BAC1.2F5 macrophages, in platelet-derived growth factor-stimulated NIH-3T3 cells, and in CSF-1-stimulated NIH-3T3 cells expressing the c-fms/CSF-1 receptor. The 57-kDa protein was phosphorylated on serine and tyrosine and was the only alpha PY-reactive protein band whose phosphorylation was reproducibly increased in GM-CSF-stimulated cells. The effect of the growth factors on the tyrosine phosphorylation of the 57-kDa protein could be mimicked by treatment of the cells with orthovanadate, a phosphotyrosine protein phosphatase inhibitor. In the absence of growth factors, tyrosine phosphorylation of the 57-kDa protein was higher in v-fms or c-fms (F969, S301)-transformed NIH-3T3 cells than in untransformed NIH-3T3 (c-fms) and NIH-3T3 (c-fms, F969) cells. These data indicate that the 57-kDa protein is a common target for growth factor-stimulated tyrosine phosphorylation and potentially important for growth factor mitogenic signaling.

Primary culture of adult mouse lung fibroblasts in serum-free medium: responses to growth factors

We report a completely serum-free system for primary culture of fibroblasts from explants of adult mouse lung tissue which permits bioassays for cytokine activity to be performed using unselected populations of cells at low passage number, without interference by serum binding proteins or interacting growth factors. Cultures were established on collagen-coated surfaces in medium MCDB 201 containing albumin, transferrin, epidermal growth factor, lipids, prostaglandin E1, vitamin E, and reducing agents. The cells were morphologically and ultrastructurally typical of fibroblasts in culture and demonstrated expression of vimentin and induction of expression of desmin in culture. Proliferation of the cells was reproducible between different primary cultures and was growth factor dependent. Both cycling and growth-arrested cells exhibited increased DNA synthesis when stimulated with epidermal growth factor, platelet-derived growth factor, or basic fibroblast growth factor, which functioned as complete mitogens, but did not respond to insulin, tumor necrosis factor or interleukin-1 beta. Maximal induction of DNA synthesis by epidermal growth factor required the continued presence of the mitogen in the culture medium. These results cannot be satisfactorily explained by the competence-progression model of responses to mitogenic stimuli but support and extend the findings of other studies using diploid fibroblasts.

[Pharmacological studies on the volatile oil isolated from the leaves of Pinus pumila (Pall.) Regel]

The sedative, analgesic, antipyretic and anti-inflammatory activities of the volatile oil isolated from the leaves of Pinus pumila are reported, the volatile oil being administered ip or po. The ip LD50 in mice was 0.577 +/- 0.056 ml/kg.

The structure of a key intermediate in the total synthesis of dendrobine

(1R*,4R*,5S*,8R*,11S*)-3,11-Dimethyl-5-hydroxy-6-isopropyl-3-azatricy clo[6.2.1.0(4,11)]undec-6-en-2-one, C15H23NO2, Mr = 249.35, monoclinic, P2(1)/c, a = 7.782(2), b = 23.119(4), c = 7.932(2) A, beta = 101.53 (2)degrees, V = 1398.1(5) A3, Z = 4, Dx = 1.184 g cm-3, Mo K alpha, gamma = 0.7107 A, mu = 0.7259 cm-1, F(000) = 544, T = 298 K, R = 0.0464 for 1887 reflections (F0 greater than or equal to 4[sigma (F0)]). The molecules are H-bonded into infinite columns parallel to c involving the hydroxyl group and the carbonyl O atom [O15...O13(x,y,z-1) 2.756(2); H15...O13 1.84(3) A; O-H...O 173(3) degrees]. The bonds from the bridgehead atom of the tricyclic ring to other ring atoms appear to be elongated [av. 1.549(2) A] compared to the other Csp3-Csp3 bonds in the molecule.

Role of dimerization and modification of the CSF-1 receptor in its activation and internalization during the CSF-1 response

We have used kinetic and cross-linking approaches to study CSF-1-induced changes in the structure and function of the CSF-1R. Addition of CSF-1 to cells stimulates or stabilizes non-covalent CSF-1R dimerization resulting in activation of the CSF-1R kinase and the tyrosine phosphorylation of the receptor and certain cytoplasmic proteins. The non-covalent dimers become covalently linked via disulfide bonds and/or are subsequently further modified. These modified forms are selectively internalized. Pre-treatment of cells with the alkylating agent, iodoacetic acid (IAA), selectively inhibits covalent dimerization, modification and internalization but enhances protein tyrosine phosphorylation. It is proposed that ligand-induced non-covalent dimerization activates the CSF-1R kinase, whereas the covalent dimerization and subsequent modification lead to kinase inactivation, phosphotyrosine dephosphorylation and internalization of the receptor--ligand complex.

Promoting heart health for Southeast Asians: a database for planning interventions

This paper is a report of baseline data that the authors collected on the prevalence of hypertension in a sample of 397 Southeast Asian immigrants residing in central Ohio and the implications of those data for the design of ethnically approved and scientifically valid interventions. The context for collection of these data over a 9-month period in 1989 is described. Baseline demographic characteristics including distributions by ethnicity, sex, age, and length of stay in the United States, as well as family heart health history, hypertension level, and heart health awareness of these subjects are presented. For example, 85 percent of the immigrants did not know what could be done to prevent heart disease. Implications for the design of ethnically approved and scientifically valid prevention strategies are discussed. Based on these data, the authors realized that multiple health education strategies tailored to what they were learning about Southeast Asians would be needed. Through Southeast Asian leaders, they were led to using wall calendars, with words specific to each Southeast Asian language, that had a monthly heart health slogan as one avenue to reach Southeast Asians. Another strategy was to develop videotapes featuring cultural content but including heart health "commercials." The authors concluded that, although scientific validity of risk reduction interventions are important, customizing these strategies to ethnically specific modes of interaction are equally important.

[Iatrogenic central artery embolism]

This paper presented 3 cases of central retinal artery embolism (CRAE) caused by the drug injection at the head and neck. In two of the three cases, the emboli were formed by the suspended drug which entered CRA resulting in the occlusion. Another case was caused by the large amount of meglucamini diatrizoas which was injected too quickly during angiography. The CRA was filled up with fluorescein in a very short time, which lead to ischemia and hypoxia of the retina. This paper stressed the importance of early diagnosis and prompt treatment. The authors also Discussed the method of drug injection at the head and neck.

[Pharmacological functions of Chinese ant oral syrup]

Experiments show that Chinese Ant Oral Syrup has functions as calmatives, fatigue-resisting agents and androgen. Also it can cause thymic atrophy in small mice, increase their oxygen-deficient endurance under normal pressures, inhibit leucocyte-decrease induced by cyclophosphamidum. The syrup is slightly toxic.

Room temperature characterization of the dioxygen intermediates of cytochrome c oxidase by resonance Raman spectroscopy

Resonance Raman spectroscopy was employed to investigate the heme structures of catalytic intermediates of cytochrome c oxidase at room temperature. The high-frequency resonance Raman spectra were obtained for compound C (the two-electron-reduced dioxygen intermediate), ferryl (the three-electron-reduced dioxygen intermediate), and the fully oxidized enzyme. Compound C was formed by photolyzing CO mixed-valence enzyme in the presence of O2. The ferryl intermediate was formed by reoxidation of the fully reduced enzyme by an excess of H2O2. Two forms of the oxidized enzyme were prepared by reoxidizing the fully reduced enzyme with O2. Our data indicate that, in compound C, cyt a3 is either intermediate or low spin and is nonphotolabile and its oxidation state marker band, v4, appears a higher frequency than that of the resting form of the enzyme. The ferryl intermediate also displays a low-spin cyt a3, which is nonphotolabile, and an even higher frequency for the oxidation state marker band, v4. The reoxidized form of cytochrome c oxidase with a Soret absorption maximum at 420 nm has an oxidation state marker band (v4) in a position similar to that of the resting form, while the spin-state region resembles that of compound C. This species subsequently decays to a second oxidized from of the enzyme, which displays a high-frequency resonance Raman spectrum identical with that of the original resting enzyme.

[Herbalogical studies on bulbus Lilii]

A textual research has been carried out herbalogically on Bulbus Lilii, along with a pharmacological study and resources investigation. Lanceleaf Lily is regarded as the first choice of the drug.

Primary malignant tumors of the trachea. A radiologic and clinical study

Fifty-four cases (55 foci) of primary tracheal malignancies were reviewed retrospectively. Radiologic material was available in 32 cases (33 tracheal foci). The most frequent primary malignant tumor of the trachea was squamous cell carcinoma (54.5%), followed by adenoid cystic carcinoma (18%) and adenocarcinoma (9%). The radiologic appearance of the tumors could be divided into intraluminal, wall-thickening, and exophytic forms. Wall-thickening and exophytic forms in this study accounted for 62% of the tumors. This indicates that malignant tumors of the trachea tend to extraluminal invasion. Tomography and computed tomography are the most helpful methods of radiologic examination for tracheal tumors. Bronchoscopy and radiologic examination are complementary procedures. The chief advantage of imaging is the demonstration of tracheal wall thickening and extraluminal changes. Hemoptysis, dyspnea, and cough were the most common symptoms. Four cases (7%) in our series presented as thyroid tumors due to direct extension into the thyroid gland. Fifteen of the 54 cases (28%) were associated with other carcinomas of the head and neck and the lung.

[The evaluation of thyroid suppression test in predicting the outcome of Graves' disease treated by short-term antithyroid drugs]

One hundred and fifteen new patients with Graves' hyperthyroidism were received thyroid suppression test after cessation of 6 month course of drug therapy. The results of follow up for another 12 months were that one of them had lost, 48 cases were in remission, and 66 cases had relapsed. The present study shows that thyroid suppression test, including the 4th, 6th and 24th hour suppression rates, is useful in predicting the outcome of drug therapy. The effect of 6th hour suppression rate is better than that of 24th and 4th hours, with 75.8% sensitivity, 75.0% specificity and 75.4% accuracy when 30% of thyroid suppression rate is as out-off point which is decided by ROC curve. It is suggested that 6 hour 30% suppression rate is better than the traditional 24 hour 50% suppression rate in the prediction of outcome of drug therapy.

Activation of lymphocytes in the pulmonary inflammatory response to silica

Lymphocytes were separated from the parenchymal lung tissue of mice administered either silica or titanium dioxide particles by intratracheal injection. There was an approximately 10-fold increase in the number of T-lymphocytes recovered from silica-treated animals at 2 weeks after injection. This was accompanied by an increase in the percentage of separated cells expressing the interleukin-2 receptor and by enhanced spontaneous DNA synthesis in serum-free culture. No such changes were demonstrable in cells obtained from animals administered titanium dioxide. These results confirm that an influx of T-lymphocytes occurs as part of the early pulmonary inflammatory response to silica particles. Furthermore, lymphocytes in the lung are functionally activated by at least two criteria. Activated T-lymphocytes may play a role in the induction of fibroblast proliferation and collagen synthesis that occurs in silicotic lung disease.