Volume 109  ·   Issue 11  ·  1996

OBJECTIVE To evaluate the relationship between certain humoral factors and left ventricular hypertrophy (LVH) in essential hypertension. PATIENTS AND METHODS 62 essential hypertension (EH) patients (32 men, 30 women; mean age, 55 years) and 20 normotensive healthy subjects (10 men, 10 women: mean age, 52 years) were studied. EH patients were divided into LVH group and non-LVH group by echocardiography. After an overnight fast, blood samples were taken for the determination of parathyroid hormone (PTH), angiotensin Ⅱ (ATⅡ) and aldosterone (ALD) by radioimmunoassay. RESULTS There was a significant difference in PTH. AT II and ALD between the EH group and control group. Furthermore, in LVH group PTH, ATⅡ and ALD elevated significantly as compared with non-LVH group. In addition, we found that LVMI (left ventricular mass index) correlated with ATⅡ (r=0.342, P<0.01) and ALD (r=0.356, P<0.01). There was a more significant correlation between LVMI and PTH (r=0.422, P<0.0025). CONCLUSIONS Some humoral factors are important determinants of LV mass. Besides the reninangiotensin-aldosterone system, PTH might play an important role in cardiac hypertrophy.

OBJECTIVE To evaluate the effects of Ginkgolide B, a specific platelet activating factor (PAF) antagonist, on hypoxia-induced pulmonary hypertension and pulmonary vascular remodeling. MATERIALS AND METHODS Forty male Wistar rats were divided into 4 groups, receiving normal saline, Ginkgolide B, isobaric hypoxia and isobaric hypoxia plus Ginkgolide B respectively. Pulmonary hemodynamics were assessed via right heart catheterization. Pulmonary vascular remodeling were examined by a computerized image analyser. RESULTS Chronic hypoxia (FiO2=0.10, 3 weeks) caused pulmonary hypertension, pulmonary vascular remodeling and right ventricular hypertrophy in rats. Treatment with Ginkgolide B reduced the extent of pulmonary hypertension, pulmonary vascular remodeling and right ventricular hypertrophy induced by hypoxic exposure. CONCLUSIONS The results suggest that PAF participates in the process of chronic hypoxic pulmonary hypertension and pulmonary vascular remodeling, and PAF antagonist could be a potentially useful agent for preventing hypoxic pulmonary hypertension.

OBJECTIVE To evaluate the outcome of hyperactive children diagnosed 15 years ago at the average age of 25. PATIENTS AND METHODS Conditions of 197 children who were diagnosed as having minimal brain dysfunction (MBD) in 1979-1980 at our center and 103 normal controls were assessed by the parents in an inquiry form including educational achievement, occupational rank, persistence of attention deficit hyperactive disorder (ADHD) (MBD) symptoms, and pervasive conduct problems after a 15-year follow-up. RESULTS Compared with normal controls, the probands continued to reveal typical symptoms in 70% of these children, completed less formal schooling, and were less often employed in higher-level professions, but did not exhibit significantly more conduct problems. CONCLUSIONS Only about 30% of the formerly hyperactive children can get out of the shadow of ADHD (MBD) and succeed in their academic or occupational performance, and the rest continue to reveal some symptoms and some problems in their adult life.

OBJECTIVE To observe the structural alterations of resistance vessels in spontaneously hypertensive rats (SHRs) and to evaluate the effects of captopril on them. METHODS 15-week-old male SHRs were treated with oral captopril (100 mg/kg/day) for 12 weeks. Age- and sex-matched SHRs and Wistar-Kyoto rats (WKY) were fed under the same conditions without captopril administration for the same duration. All rats were killed at the age of 27 weeks. The structural parameters included media width, lumen diameter, media-lumen ratio, vascular collagen area (VCA) and vascular collagen density (VCD). The media width, lumen diameter and media-lumen ratio were measured in hhematoxylin and eosin staining sections under a direct light microscope and VCA and VCD in picrosirius red staining sections under a polarizing light microscope. All the values were processed with a computer image analyzer. RESULTS There were thicker media width, smaller lumen diameter, higher media-lumen ratio and larger VCA in untreated SHRs than in WKY. Captopril inhibited media thickening, with lumen diameter decreasing, media-lumen ratio increasing and VCA enlarging. There was no significant difference in VCD among the three groups. CONCLUSIONS Adverse structural alterations occur in resistance vessels of SHRs and captopril may prevent their progression.

OBJECTIVE To study the effect of extended parietal cell vagotomy (EPCV) on long-term nutritional status and digestive-absorption function. PATIENTS AND METHODS Thirty-six patients undergoing EPCV were compared with 30 patients with subtotal gastrectomy (SG) 7-14 years after operation. The patients were evaluated in terms of nutritional status, gastric secretion, gastrointestinal motility, and intestinal digestive-absorption function. RESULTS The nutritional status was generally less satisfactory in 33.3% patients with anemia after SG and body weight decreased in 54%. The patients after EPCV were all in good nutritional status, and had no symptoms of anemia; 56% of them had body weight increased by more than 3 kg. The mean basal acid output (BAO), maximal acid output (MAO), and peak acid output (PAO) of the EPCV group were significantly reduced after operation (P<0.01), and moderately reduced as compared with those of the control group (P>0.05). But the BAO, MAO, and PAO of the SG group were more markedly reduced than those of the control group (P<0.001) before operation. Vitamin B12, folacin, intrinsic factor and iron protein level of serum in the EPCV group were slightly decreased as compared with those of the control group (P>0.05), but more significantly decreased in the SG group than in the control group (P<0.001). Iron protein and intrinsic factor level was lower than the normal level. The gastric emptying time and small intestinal passthrough time of EPCV were more close to the normal physiological status, but in the SG group, they were significantly fast (P<0.001). The results of intestinal D-xylose absorption test in EPCV and SG groups were similar (P>0.05). CONCLUSIONS EPCV is capable of preserving gastric acid of physiologic level and normal digestion-absorption function. The effect of EPCV on long-term nutrition and digestion absorption function was extremely milder than that of SG. Therefore, a theoretical basis is provided for the rationality of EPCV.

OBJECTIVE To observe changes in the content of myocardial angiotensin Ⅱ and its role in cardiac dysfunction of rat during septic shock. METHODS Septic shock model was produced by cecal ligation and puncture (CLP) operation on rats. Experimental rats were given captopril 15 mg·kg-1/d per os for 3 days before CLP operation. Mean blood pressure and left ventricular pressure were recorded. Myocardial angiotensin converting enzyme (ACE) activities were determined by a fluorometric assay and myocardial angiotensin Ⅱ content was measured by radioimmunoassay. Highly purified membrane of sarcoplasmic reticulum (SR) was prepared from rat hearts. Assays were made of ATP-dependent Ca2+ uptake by cardiac SR and (3H) ryanodine binding to SR. RESULTS Myocardial angiotensin Ⅱ content increased by 51.5% (P<0.01) at the 18th hour post CLP, meanwhile there was a decrease in left ventricular ± dp/dtmax value and the impairment in Ca2+ uptake and (3H) ryanodine binding to cardiac SR. Preliminary administration of captopril reduced myocardial ACE activity and angiotensin Ⅱ content, but increased left ventricular ± dp/dtmax value. In comparison to shock group, the initial rate and the capacity of SR Ca2+ uptake were increased by 120% (P<0.01) and 33.9% (P<0.05), the Bmax value of (3H) ryanodine binding to SR was also elevated, while the Kd value remained unchanged. CONCLUSIONS The elevated intracardiac angiotensin Ⅱ, resulting from the activation of myocardial ACE during sepsis, probably serves as one of the important mediators participating in the pathogenesis of heart failure: the effects of angiotensin Ⅱ may be associated with the disturbance of Ca2+ transport function of cardiac SR.

OBJECTIVE To determine whether mutation of the coding or junction region of glucokinase gene (GCK) is also the pathogenic cause of the common form of non-insulin-dependent diabetes mellitus (NIDDM) in Chinese. METHODS Single strand conformation polymorphism (SSCP) analysis was performed after the 12 exons and junction regions of GCK of each subject studied were separately amplified with polymerase chain reaction (PCR). The molecular scanning was carried out in 30 Chinese subjects with common form NIDDM having the age of onset at or before 45 years, and/or with positive family history of diabetes mellitus (NIDDM-A group). Further screening of the mutation/variation found was conducted in 56 NIDDM subjects (NIDDM-B group) and 134 non-diabetes subjects (ND group) in order to define their frequencies. RESULTS No mutation was found by molecular scanning in coding or junction region of GCK in NIDDM-A group. A variant of intron I b was detected in GCK of NIDDM subjects, especially in those with early age of onset and/or with positive family history of diabetes. Significant difference in incidences was found between ND group and NIDDM-A+B group (0% vs 4.7%, Fisher exact P=0.022). CONCLUSIONS (1) Mutation of coding and junction regions of GCK is not the main pathogenic factor of common form NIDDM in Chinese subjects. (2) A variant of GCK intron I b may be found in NIDDM in Chinese, especially in those with early age of onset and/or with positive family history of diabetes. Its role in the expression of GCK remain to be elucidated.

OBJECTIVE To detect the factors responsible for the susceptibility of cervical keratinocytes infected with human papillomavirus (HPV) to non-specific lysis mediated by natural killer (NK) and lymphokine activated killer (LAK) cells. METHODS Five cervical keratinocyte lines: CaSki, SiHa, HeLa (representing high grade squamous intraepithelial lesion (HSIL) ), W12 (representing low grade squamous intraepithelial lesion (LSIL) ) and NCx, (normal cervix) were used as target cells in the four-hour lactate dehydrogenase (LDH) release cytotoxicity assay. The effector cells were NK and LAK. The modulatory effects of interferon gamma (IFNγ) and tumor necrosis factor α (TNFα) pretreatment of keratinocytes were investigated by adding IFNγ or TNFα into the flasks of target cells 48 hours before the cytotoxicity assays. The blocking effects of anti-intercellular adhesion molecule-1 (ICAM-1) and anti-lymphocyte function-associated antigen-1 (LFA-1) monoclonal antibodies (Mabs) were also studied. RESULTS All the 5 cervical keratinocytes were susceptible to LAK, but not to NK. The sensitivity varied among the cell lines. LAK had better killing effects on HSIL than on LSIL. Pretreatment of target cells with IFNγ and TNFα increased the killing mediated by LAK, but had little effect on NK activity. Anti-ICAM-1 and anti-LFA-1 Mabs inhibited LAK-mediated cytotoxicity. CONCLUSIONS All the HPV infected keratinocytes used in the experiments are NK-resistant and LAK-sensitive cells. IL-2, IFNγ and TNFα play some critical roles in the regulation of the susceptibility of cervical keratinocytes, especially HSIL to LAK-mediated cytotoxicity in vitro.

OBJECTIVE To examine the prophylactic effect of artesunate on schistosomiasis japonica by killing schistosomula. METHODS Mice, rabbits and dogs after infection with cercariae of schistosoma japonicum (S. japonicum) were treated with artesunate on the 7th day at a dose of 300 mg/kg, 20-40 mg/kg and 30 mg/kg respectively once a week for 4-6 weeks. A double-blind test was used. A total of 864 persons in highly endemic areas for schistosomiasis were administered either artesunate at a dose of 6 mg/kg once a week for 8 weeks or identical placebo with the same dose-schedule during transmission season for S. japonicum. Four weeks after the last dosing, fecal examinations for S. japonicum eggs and miracidia were carried out to evaluate the prophylactic effect. RESULTS Worm reduction rates in mice, rabbits and dogs were 77.50-90.66%, 99.53% and 97.10% respectively. All of the 467 residents in 2 trials were free from eggs or miracidia upon stool examinations whereas in the control groups with placebo, 15 out of 218 (6.9%) and 26 out of 179 (14.5%) were stool eggs and/or miracidia positive in the first and second trial, respectively. Side effects were mild. No significant changes in routine blood and urine tests, electrocardiogram, hepatic and renal functions were observed after artesunate administration. CONCLUSIONS Animal experiments and field trials have demonstrated good efficacy of artesunate on killing schistosomula with little side effects. Thus, the drug is suggested to be used on the population in endemic areas for prevention of schistosomiasis.

OBJECTIVE To establish predicted values of membrane diffusing capacity (Dm) and pulmonary capacity blood volume (Vc), to compare the predicted values from our equations with those for Caucasians, to determine whether there are changes initially in Dm or Vc in patients with mild emphysema. PATIENTS AND METHODS Diffusing capacity for carbon monoxide (DLco), Dm and Vc were determined in 86 normal subjects and 16 patients using the single-breath diffusing capacity for carbon monoxide (DLcosB) with two different alveolar concentrations of oxygen. RESULTS The predicted equations are as follows. For males, DLco (ml/min/mm Hg)=0.37H-0.19A-27.8; Dm (ml/min/mm Hg)=0.65H-0.24A-53.7; Vc(ml)=0.88H-78.9. For females, DLco=0.28H-22.7; Dm=0.59H-53.6; Vc=66.6-0.36A. DLco and Vc are lower in Chinese than Caucasians while Dm is similar in Chinese and Caucasians. Eleven of 16 patients had a low DLco (<80% predicted value), 12 had a low Dm and 5 had a low Vc. Eight of 12 patients with a low Dm also had a low DLco, but in 4 the DLco was normal. Nine of 12 with low Dm had a normal Vc. CONCLUSIONS This study provides prediction equations of Dm and Vc. Chinese have a low DLco because their Vc is lower than Caucasians. The DLco and Dm are abnormal in a comparable percentage of patients. In patients with mild emphysema, the Dm becomes abnormal before the Vc.