Volume 111  ·   Issue 10  ·  1998

OBJECTIVE To observe the inhibitory effects of Radix Astragali (RA) on hypoxic structural remodeling of intraacinar pulmonary arteries (IAPA) and pulmonary hypertension (PHT). METHODS Sixty rats were divided into three groups: hypoxia group, hypoxia + RA group and normal control group. The rats of hypoxia group and hypoxia + RA group were fed in hypoxic environment under normal atmospheric pressure (10% O2, 10 h/day). On the 15th and 30th day of hypoxia, right ventricular systolic pressure (RVSP) and right ventricle hypertrophy index (RVHI) were measured and pulmonary vessel changes were studied under light and electron microscope and with morphometric analysis. RESULTS Compared with the result of hypoxia + RA group, RA could relieve IAPA wall cell injuries and dilate the constricted IAPA induced by hypoxia. RA could also inhibit hypertrophic changes in the tunica media and proliferation of adventitial cells of the IAPA and muscularization of nonmuscular arteries. CONCLUSIONS By preserving the IAPA wall cells and dilating IAPA, RA may play an important role in inhibiting the remodeling of IAPA and preventing PHT.

OBJECTIVE To detect the changes in blood coagulation system and clarify the related mechanisms of chemotherapy-induced disseminated intravascular coagulation. METHODS Changes in blood coagulation system and immunohistochemistry for fibrinogen were investigated in six groups of rats designed for different purposes. RESULTS Decreased platelet count, prolonged prothrombin time and active partial thromboplastin time, elevated fibrinogen level, and decreased antithrombin were observed in the rats receiving a newly developed chemotherapy (NDC group), in which mitomycin C was administered intravenously together with angiotensin. Accumulation of fibrinogen and microthrombi in the blood vessels of multiple organs were also found in the NDC group by immunohistochemistry and histopathological examination. CONCLUSIONS Rapid reduction of tumor mass induced by an effective chemotherapy could cause hypercoagulable state and disseminated intravascular coagulation.

OBJECTIVE To determine whether prostaglandin E2 (PGE2) influences the dog skeletal muscle circulation by a direct action on the vascular smooth muscle or via pre- or post-synaptic modulation of sympathetic neurotransmission. METHODS In 18 anaesthetised dogs, a gracilis muscle was vascularly isolated and perfused at constant flow. Sympathetic vasoconstrictor tone on the muscles was reflexly controlled by alterations to the pressure at which the isolated carotid sinuses were perfused. The effects of PGE2 injection into the muscle were compared at low carotid sinus pressure, high carotid sinus pressure, and following denervation of the muscle, with or without noradrenaline infusion. RESULTS At all levels of sympathetic tone, PGE2 produced significantly more vasodilation than the saline vehicle. However, at a carotid sinus pressure of 46.0±2.3 mmHg (1 mmHg = 0.133 kPa), PGE2 caused a decrease in femoral arterial perfusion pressure of 52.6±7.1 mmHg, which was significantly greater than the response at a carotid sinus pressure of 208.5±3.7 (33.6±4.2 mmHg decrease) or following denervation (25.6±3.7 mmHg decrease). In a separate group of denervated muscles, PGE 2 caused a similar decrease in perfusion pressure in the presence or absence of a noradrenaline infusion. CONCLUSIONS PGE2 appears to cause vasodilation through two separate mechanisms: one mechanism involves presynaptic inhibition of sympathetic vasoconstrictor tone, whilst the other is independent of the sympathetic nervous system, and is therefore presumably a direct action on the vascular smooth muscle or endothelium. Under our experimental conditions, both mechanisms contributed equally to the vasodilation.

OBJECTIVE To identify the effects of tuberculin purified protein derivative (PPD) sensitization on attenuating pulmonary T helper 2 (Th2) reaction and eosinophil infiltration in ovalbumin sensitized mice, and to search for the possibility of its clinical use in the management of asthma in a new way. METHODS Sixty C57BL/6 mice were sensitized with PPD and then with ovalbumin and aluminum hydroxide, and randomized into 4 groups: ovalbumin (OVA), pre-PPD, post-PPD and control groups. Aerosol PPD were administered 3 h before or after ovalbumin challenge in the pre-PPD and post-PPD groups respectively, and control group received aerosol PPD only. IL-4, IL-5 expression was detected by immunocytochemistry in situ hybridization. Lung slides were stained with eosin and hemotoxylin, and pathological changes were observed. RESULTS Ovalbumin aerosol inhalation caused a mixed inflammatory infiltration dominated by CD4+ T lymphocytes and eosinophils in the lung of sensitized mice. 87.5%-89.7% and 89.0%-89.2% of the CD4+ T lymphocytes were IL-4 mRNA+ and IL-5 mRNA+ respectively. 88.7%-91.2% of IL-4 mRNA+ cells and 89.8%-90.6% of IL-5 mRNA+ cells were CD4+ T lymphocytes in OVA group. Aerosol administration of PPD markedly suppressed IL-4 and IL-5 expression, and lung eosinophil infiltration. It was more effective in pre-PPD group. 76.6%-78.0% of IL-4 mRNA+ and 73.8%-79.7% of IL-5 mRNA+ cells were CD4+ and 78.1%-84.9% and 78.4%-85.3% of the CD4+ cells were IL-4 mRNA+ or IL-5 mRNA+ respectively in pre-PPD group, both were markedly lower than that of OVA group. CD4+ percentage of IL-4 mRNA+ and IL-5 mRNA+ cells were 80.7%-82.0% and 78.0%-83.9% in post-PPD group, which were markedly lower than that of OVA group. CONCLUSIONS Sensitization with PPD by intraperitoneal injection and then challenged by PPD inhalation markedly suppressed IL-4, IL-5 expression and eosinophil infiltration, and attenuated pulmonary Th2 reaction in ovalbumin sensitized mice. This induces Th1 type reaction and inhibits Th2 cell differentiation. It may be beneficial for glucocorticoids dependent or resistant patients.

OBJECTIVE To investigate the pathogenetic mechanisms leading to the development of calcific degeneration of the aortic valve in the elderly patients with particular reference to the relationship between apoptosis and calcification in the aortic valve tissue. METHODS High resolution scanning and transmission electron microscopic observations of the calcified aortic valves obtained during aortic valve replacement were carried out in 10 patients with senile calcific aortic stenosis. RESULTS Various degrees of endothelial alterations from focal disruption of individual endothelial cells to extensive denudation of entire endothelium were observed particularly on the aortic side of the valve tissues. The apoptotic changes occurring in the nuclei of endothelial cells and fibroblasts were common findings in the calcified valve tissues. It was noteworthy that the severity of endothelial damage was closely related to apoptotic changes of the fibroblasts. Calcific deposits were frequently observed in association with the cellular fragments mainly derived from the apoptotic fibroblasts. CONCLUSIONS Our results strongly indicate that apoptosis may play an important role in the alterations of endothelial integrity leading to the increased filtration of calcium into the deeper layer of the valve tissues. Then, the cellular degradation products and organelles extruded from the dead cells, mainly resulted from apoptosis provided the substrates for calcium binding with progressive development of calcification in the valve tissue. Although the role of apoptosis in contribution to the pathogenesis of senile calcific aortic stenosis is evident, further studies using modern molecular biotechnology are mandatory in order to clarify the mechanism for the initiation of apoptotic process in the endothelial cells and fibroblasts.

OBJECTIVE To investigate the ultrastructural pathological alterations of the microvasculature and nerve fibers in the endomyocardial biopsied specimens of the left ventricular myocardium obtained from patients with idiopathic dilated cardiomyopathy and chronic heart failure. METHODS Transmission electron microscopic observations of endomyocardial biopsied specimens of the left ventricular myocardium were carried out in 10 patients with idiopathic dilated cardiomyopathy and chronic heart failure. RESULTS Various degrees of ultrastructural pathological alterations in the microvessels and sympathetic nerves in the diseased myocardium were consistently demonstrated in idiopathic dilated cardiomyopathy. In addition, abnormal accumulation of collagen tissue and edematous fluid were often seen in the interspace between myocardial cells and nerve endings and capillaries. CONCLUSIONS Based on the ultrastructural pathological findings in this study, we consider that all the structures forming the muscle cells and the tissues around them, namely the microvessels and nerves may participate in the pathological process in the course of dilated cardiomyopathy. The damage of microvasculature and sympathetic nerves resulting from the underlying disease processes are considered to be an important pathogenetic mechanism responsible for progressive development of myocardial degeneration and dysfunction throughout the course of the disease. It is hoped that our data may provide some insights into the understanding of the role of microcirculation and sympathetic nerves in the etiopathogenesis of dilated cardiomyopathy.

OBJECTIVE To compare the results of treatment of atrial fibrillation (Af) with maze procedure by radiofrequency in 25 patients undergoing mitral valve replacement operation (MVRO) (treatment group) with those in 25 patients undergoing MVRO only (control group). METHODS The maze procedure modified was completed by radiofrequency ablation with macroscopy during MVRO in the treatment group, whereas the patients in the control group underwent MVRO only. No one in the two groups took antiarrhythmic drugs before and after operation. RESULTS The heart rhythm became stable sinus rhythm in 22 of 25 patients of the treatment group after operation and the success rate was 88.0%. Af recurred in none of the 22 patients during the follow-up for 3-24 months. In the control group, 5 patients showed transient sinus rhythm, but Af recurred when they left hospital. CONCLUSIONS Maze procedure by radiofrequency ablation is an effective method to cure Af and its success rate was the same as that of surgical incision and cryolesion. But the former took 10-15 minutes only with light damage of atrial muscle and no bleeding, whereas the latter took 1-1.5 hours.

OBJECTIVE To compare the long-term efficacy of a dose of 3 million units (MU) of r-IFN alpha 2a (IFN-α2a) three times a week (t.i.w.) for 6 months with a starting dose 6 MU for 3 months and subsequent reduction to 3 MU t.i.w for further 3 months. METHODS Sixty-eight serological and histological chronic hepatitis C patients with elevated serum alanine aminotransferase (ALT) were enrolled and randomized into two groups. Sixty-three patients were completed with full course of treatment. Five patients were withdrawn from trial (2 due to personal reasons and 3 due to adverse drug reactions during treatment). Thirty patients received 6 MU IFN-α2a t.i.w., 3 months followed by 3 MU t.i.w. for another 3 months (Group A). Thirty-three patients received 3 MU IFN-α2a t.i.w. for 6 months (Group B). RESULTS The sex, age, baseline serum bilirubin, ALT and aspartate aminotransferase (AST) levels were matched in both groups. At the end of the 6th month, the complete and partial response rates in Group A were 60.0% and 16.7% respectively, and the clearance of serum HCV-RNA was 53.3%. In Group B, the complete and partial response rates were 72.7% and 6.1% respectively, and the clearance of HCV-RNA was 61.3%. The patients were followed up for 6, 12, and 18 months after stopping treatment. In Group A, the rates of complete normalization of ALT and clearance of serum HCV-RNA at 24 months were 50.0% and 60.0% respectively. In Group B, the rates of normalization of ALT and clearance of HCV-RNA at 24 months were 54.4% and 41.9% respectively. The efficacy between the two groups showed no statistically significant difference. The response rates of treatment were similar to those in the patients with HCV genotype 1b and 2a. Six patients (10.8% of the study population) developed neutralization antibodies to IFN-α2a during treatment, and four of them were responded to the treatment. Adverse drug reactions (ADR), were common, but most of them were tolerable, and the incidence of ADR was in both groups, but the severity was higher in Group A. CONCLUSIONS IFN-α2a is effective in the treatment of Chinese patients with chronic hepatitis C. The sustained response rates and adverse drug reactions among two dose schedule groups are similar.

OBJECTIVE To study the effect for albendazole therapy for alveolar echinococcus infection in gerbils and mice. METHODS Mice and gerbils were infected of metacestode tissues by intraperitoneal (IP) transplantation and treated with albendazole-medicated feeds. The effects were evaluated by comparison of the treated and control groups in terms of host mortality, larval metastases to lungs and liver, final larval weight, histopathological, and ultrastructural examination of metacestode tissues. Viability of metacestode tissues at necropsy of treated animals was tested by intraperitoneal transplantation into uninfected animals. RESULTS Albendazole-medicated feeds significantly inhibited larval growth of Echinococcus multilocularis (E. multilocularis) both in mice and gerbils with markedly reduced host mortality and pulmonary and liver metastases. Viability test showed that albendazole therapy was parasiticidal in early stage of experimental infection. Light microscopic and ultrastructural examination of metacestode tissues of the treated animals revealed severe destruction and massive necrosis with marked calcification of protoscoleces and residual tissues. CONCLUSIONS Continuous long term albendazole therapy in animal models is parasiticidal against larval E. multilocularis especially in early stage of infection.

OBJECTIVE To investigate the clinical and bacteriologic features of patients with systemic lupus erythematosus (SLE) complicated by bacterial and/or fungal infections. METHODS Statistical analysis was made on basis of the clinical and bacteriologic data of 86 patients with SLE complicated by bacterial and/or fungal infections. RESULTS One hundred and thirty-three episodes of infections occurred in 86 patients with SLE, in which 51.13% were nosocomial infections and 76.69% occurred in the blood system, respiratory tract, lungs and urinary tract. Gram-negative bacilli, gram-positive cocci, fungal and other bacterial infections accounted for 39.85%, 31.58%, 18.80% and 9.77%, respectively. In the bacterial infections, 18.52% were caused by L-form bacteria and more than 60% of the patients had no apparent toxic manifestations. The odds ratio (OR) of infection increased significantly in patients with damaged functions of the heart, lungs and kidneys, and in those who received high-dosage steroids. CONCLUSIONS Patients with SLE tend to develop nosocomial infections with gram-negative bacilli which are the most common pathogens. The clinical manifestations of the infection are atypical. Careful inspection and monitoring, timely collecting the specimens for L-form bacterial culture can reduce misdiagnosis and missed diagnosis of the infection.

Madelung reported 33 patients with cervical lipomatosis and Launois and Bensaude as the presence of multiple symmetrical unencapsulated fat accumulations diffusely involving the cervical and upper dorsal regions, abdomen and groin. We present the ultrasound (US) and computed tomographic (CT) finding in two Chinese patients.