Heterogeneity in the social networks of young and older adults: prediction of mental health and cardiovascular reactivity during acute stress.

We examined the utility of a broad framework that separated positive, negative, and ambivalent social network members. One hundred thirty-three young and older participants completed the social relationships index, measures of mental health, and a cardiovascular reactivity protocol. Results replicated prior research on the beneficial influence of positive (supportive) ties on psychological outcomes. More important, analyses also revealed that the number of ambivalent network ties predicted age-related differences in depression and sympathetic control of heart rate reactivity during stress. The statistical interactions between age and ambivalent ties on cardiovascular responses during stress were not changed when statistically controlling for other social network categories, demographic variables, and various personality factors. These data suggest that social network ambivalence was a relatively unique predictor of cardiovascular reactivity and highlight the utility of separating the variance due to positive, negative, and ambivalent network ties. Implications for the study of social relationships, physiological processes, and health outcomes are also discussed.

[Synchronous primary triple cancers including the lung, stomach, and thyroid: a case report].

A 62-year-old man with synchronous multiple primary cancers involving the lung, stomach, and thyroid was admitted. Initially the patient's chest X-ray showed an abnormal shadow in the right middle-lobe indicating lung cancer. During preoperative examination, gastric cancer of the antrum and angle were detected. Excisional biopsy of the lymph node in the neck after chest surgery revealed thyroid cancer. A middle lobectomy with mediastinal lymph node dissection was performed for lung cancer and the histological diagnosis was moderately differentiated adenocarcinoma, pT4N2M0, stage IIIB. Gastric cancer was treated by endoscopic mucosal resection. Considering the relatively better prognosis of papillary thyroid cancer, we concluded that no further treatment to the thyroid lesion was necessary. In Japan, according to autopsy reports, triple primary cancers are gradually increasing. During the periods 1994 to 1996, the incidence of triple cancers was 0.81% of all autopsy cases reported.

Social support and age-related differences in cardiovascular function: an examination of potential mediators.

The investigators examined the potential influence of social support on age-related differences in resting cardiovascular function and the potential mediators responsible for such associations in 67 normotensive women and men. Consistent with prior research, age predicted increased resting systolic blood pressure (SBP) and diastolic blood pressure (DBP). More importantly, regression analyses revealed that social support moderated age-related differences in resting SBP and DBP, as age predicted higher resting blood pressure for individuals low in social support, but was unrelated to blood pressure for individuals high in social support. An examination of potential pathways revealed that these results were not mediated by various health-related variables, personality factors, or psychological processes. Implications for the study of social support and health are discussed.

Age-related differences in cardiovascular reactivity during acute psychological stress in men and women.

We examined potential age and gender differences in cardiovascular reactivity during acute psychosocial stress in 133 normotensive participants using a cross-sectional design. Results revealed that age predicted increased systolic blood pressure (SBP) reactivity during stress (p < .001). The greater SBP reactivity found in older individuals appeared due to an age-associated increase in both cardiac output and total peripheral resistance during stress as statistically controlling for these changes rendered the age and SBP reactivity effect nonsignificant. Similar analyses revealed that the age-related increase in cardiac output reactivity appeared to be driven by increased cardiac sympathetic control of myocardial contractility as measured by pre-ejection period. Older individuals also had greater vagal withdrawal during stress compared to younger individuals as indexed by respiratory sinus arrhythmia (p < .01). These results were comparable for men and women, and could not be explained by task-specific affective responses, task performance, or demographic factors. Implications for the study of age, cardiovascular reactivity, and health are discussed.

A possible involvement of oxidative lung injury in endotoxin-induced bronchial hyperresponsiveness to substance P in guinea pigs.

Reactive oxygen-derived free radical species have been implicated in the pathogenesis and pathophysiology of inflammatory lung diseases. In a guinea pig model of aerosolized endotoxin-induced bronchial hyperresponsiveness to substance P, a possible involvement of oxidative lung injury was assessed by measuring the changes in membrane-bound neutral endopeptidase activity in the airway tissues and the level of lipid peroxides in the plasma. Vehicle-treated animals developed a neutrophilic airway inflammation, bronchial hyperresponsiveness to substance P associated with neutral endopeptidase hypoactivity, and elevation of lipid peroxides at 18 to 24 h after an exposure to endotoxin (75 microgram/ml, 40 min). A nonselective phosphodiesterase inhibitor, aminophylline, and selective phosphodiesterase isoenzyme inhibitors, SDZ-ISQ-844 (type III/IV) and SDZ-MKS-492 (type III), attenuated the neutrophilic airway inflammation induced by endotoxin. Aminophylline, SDZ-MKS-492, and a superoxide anion-generating NADPH-oxidase inhibitor apocynin inhibited bronchial hyperresponsiveness to substance P with attenuation of neutral endopeptidase inactivation induced by endotoxin. SDZ-ISQ-844, SDZ-MKS-492, and apocynin attenuated the elevation of lipid peroxides. The generation of hypochlorite (OCl-) from whole blood leukocytes was attenuated by aminophylline, SDZ-ISQ-844, SDZ-MKS-492, and apocynin at 1 to 2 h after exposure. These results suggest that reactive oxygen-derived free radical species-mediated oxidative lung injury may play an important role in endotoxin-induced bronchial hyperresponsiveness to substance P, and that phosphodiesterase isoenzyme inhibitors may be potentially useful as anti-inflammatory drugs.

Effects of the calcium ionophore A23187 on airway responsiveness to histamine and substance P in guinea pigs.

OBJECTIVE: We evaluated the mechanism of the airway hyperresponsiveness (AHR) induced by a calcium ionophore in guinea pigs. MATERIALS AND METHODS: Airway responsiveness to intravenous histamine (HS) and substance P (SP) was measured 24 h after a 1-h exposure to aerosolized A23187 (0.03 or 0.1 mg/ml) or its vehicle (10% DMSO). Changes were assessed by calculating -logPC350HS and logPC350SP. Neutral endopeptidase (NEP) activity in the airway tissues, as well as the nitrite (NO2) levels and the cell population in bronchoalveolar lavage fluid (BALF) was determined after measurement of pulmonary function. Changes in SP-induced vascular permeability 24 h after exposure to A23187 were measured by the Evans Blue dye extravasation technique. RESULTS: Exposure to A23187 caused a significant AHR to SP, along with a significant increase in the number of neutrophils and epithelial cells in the BALF. While there was no significant change in NEP activity in the airway tissues, the levels of nitrite in the BALF were significantly decreased in A23187-exposed animals. Significant correlations were found between the number of epithelial cells in the BALF and logPC350SP (r = 0.477, p < 0.05) and between nitrite levels in the BALF and -logPC350SP (r = 0.491, p < 0.05) A23187 exposure did not significantly change the SP-induced airway microvascular leakage. CONCLUSIONS: These data suggest that A23187 exposure induced AHR to SP possibly by reducing NO levels in the airway tissues. This may be due to damaged airway epithelium and/or NO breakdown by activated inflammatory cells in the airways of these guinea pigs.

[A case of intractable status asthmaticus treated by isoflurane inhalational anesthesia and bronchial lavage].

A case of severe asthmatic attack treated by isoflurane inhalational anesthesia and bronchial lavage is reported. A 24-year-old woman was admitted to our hospital with severe asthmatic attack. Although she was treated by intravenous administration of aminophylline and corticosteroids, pulmonary function and consciousness deteriorated. Therefore, she was intubated nasally and mechanically ventilated by IPPV with administration of aminophylline, corticosteroids and epinephrine. Despite this treatment, she remained in status asthmaticus with high airway pressure and barotrauma causing pneumomediastinum and subcutaneous emphysema. On the 3rd hospital day, a system was arranged so that isoflurane could be given in an air and oxygen mixture, and administration was started with a concentration of isoflurane of 1.5%. In addition, bronchial lavage via bronchoscopy was performed in order to clear any mucous plugs. After 24 hours, there was marked improvement of wheezing, airway pressure and arterial blood gas level. Eventually, she was weaned from the ventilator on the 6th hospital day without significant side effects. The use of halothane inhalational anesthetic treatment for status asthmaticus is widely known, but it has serious side effects such as arrhythmia and liver injury. Isoflurane may be the inhalational anesthetic agent of choice in the treatment of status asthmaticus.

Naturally occurring aliphatic polyamines-induced histamine release from rat peritoneal mast cells.

Rat peritoneal mast cells were incubated with different concentrations of naturally occurring aliphatic polyamines, spermine and spermidine, at 0.1-10 mM and the amount of histamine release into the supernatant solutions was measured. The addition of each polyamine to the suspensions of the mast cells caused a histamine release in a dose-dependent manner. The effect of 10 mM spermine and spermidine was as much as that of 0.5 microgram/ml compound 48/80. The histamine release from the cells incubated with each polyamine was rapid and the amount of histamine release into the supernatant solutions reached a maximum at 1 min with the incubations. 0.1 mM spermine, which in itself could not cause a significant histamine release, showed a tendency to enhance anti-IgE-induced histamine release from the mast cells.

[Naturally occurring aliphatic polyamines-induced histamine release from rat peritoneal mast cells].

Rat peritoneal mast cells obtained by Percoll gradient were incubated with different concentrations of naturally occurring aliphatic polyamines, spermine and spermidine, at 0.1-10 mM and the amount of histamine release into the supernatant solutions was measured. The addition of each polyamine to the suspensions of the mast cells caused a histamine release in a dose-dependent manner. The histamine release from the cells incubated with each polyamine was rapid and the amount of the histamine release into the supernatant solutions reached maximum at one minute with the incubations.

Polyamines stimulate the phosphorylation of phosphatidylinositol in rat mast cell granules.

Rat mast cell granules were obtained by homogenization of highly purified rat mast cells and isolated in a Percoll gradient. Diphosphoinositide (DPI) synthesis in rat mast cell granules was assayed by measuring the incorporation of 32P from [gamma 32P] ATP into DPI in the absence of exogenous phosphatidylinositol (PI). Lipids were isolated with methanol/chloroform/HCl and were separated by thin-layer chromatography on oxalic acid impregnated silica gel plates. DPI areas were identified by staining with iodine, scraped and measured for 32P radioactivity. The addition of polyamines, spermine and spermidine, to the granules caused an increase of DPI synthesis, which can be catalyzed by PI kinase. This effect of polyamines in the DPI synthesis was in a dose-dependent manner and maximal effects were observed at 1 mM spermine and 10 mM spermidine, respectively.

[Polyamines stimulate the phosphorylation of phosphatidylinositol in rat mast cell granules].

Rat mast cell granules were obtained by homogenization of highly purified rat mast cells and isolated in a Percoll gradient. Diphosphoinositide (DPI) synthesis in rat mast cell granules was assayed by measuring the incorporation of 32P from [gamma 32] ATP into DPI in the absence of exogenous phosphatidylinositol (PI). Lipids were isolated with methanol/chloroform/HCl and were separated by thin-layer chromatography on oxalic acid impregnated silica gel plates. DPI areas were identified by staining with iodine, scraped and measured for 32P radioactivity. The addition of polyamines, spermine and spermidine to the granules caused an increase in DPI synthesis, which can be catalyzed by PI kinase. This effect of polyamines on DPI synthesis in the rat mast cell granules was dose-dependent and maximal effects were observed at 1 mM spermine and 10 mM spermidine respectively. When the effect of 1 mM spermine on 32P incorporation into DPI in rat mast cell granules was investigated serially, 32P incorporation into DPI in rat mast cell granules incubated with spermine for 15 min was enhanced significantly (p less than 0.05) compared with that in the granules in the absence of spermine.

[Effect of phorbol myristate acetate (PMA) on diphosphoinositide (DPI) synthesis in rat mast cell granules].

Rat mast cell granules were obtained by homogenization of highly purified rat mast cells and isolated in a Percoll gradient. DPI synthesis in rat mast cell granules was assayed by measuring the incorporation of 32P from [gamma 32P] ATP into DPI in the absence of exogenous phosphatidylinositol (PI). Lipids were isolated with methanol/chloroform/HC1 and were separated by thin-layer chromatography on oxalic acid impregnated silica gel plates. DPI areas were identified by staining with iodine, scraped and measured for 32P radioactivity. The addition of PMA to the granules caused an increase of DPI synthesis, which can be catalysed by PI kinase. Neither an inactive phorbol ester, 4-alpha-phorbol-12, 13-didecanoate, nor dimethyl sulfoxide (DMSO) used as a solvent for PMA had any effect. The effect of PMA in the DPI synthesis was dose-dependent and maximal effects were observed at 10-100 ng/ml. Dose-response curves of the effects of PMA in DPI synthesis in the granules corresponded to those of other biochemical effects of PMA in rat mast cells, such as mediator release mediated through the activation of protein kinase C. These results suggest that PMA may directly affect PI kinase or indirectly regulate its activity in rat mast cell granules.

Nature of renal involvement in the acro-renal-ocular syndrome.

A 16-year-old female with acro-renal-ocular syndrome complicated by ventricular septal defect is described. Renal biopsy was performed for the first time in this syndrome, and the results suggested that proteinuria and renal dysfunction were caused by chronic pyelonephritis secondary to malrotation of the kidney and anomalous pelves. Chronic renal failure and hypoplasia of the optic papillae were also observed in the patient's mother, suggesting a participation of heredity in the pathogenesis of the syndrome.

Effect of acute unilateral renal denervation on tubular sodium reabsorption in the dog.

The effects of acute denervation of the kidney on renal tubular sodium and water excretion were studied in anesthetized, hypophysectomized, and cortisone-treated mongrel dogs during stable water diuresis produced by the infusion of 2.5% dextrose. In all experiments, denervation natriuresis, and diuresis were observed without significant change in glomerular filtration rate (GRF) and renal plasma flow (RPF). Fractional sodium delivery to the distal nephron (CNa + CH2O/100 ml GFR) and fractional free water clearance (CH23/100 ml GFR) was significantly greater in the denervated kidney compared with the innervated kidney (9.6+/-1.2 vs. 6.7+/-0.9% and 8.8+/-1.2 vs. 6.5+/-0.8%, respectively). Distal tubular sodium reabsorption (CH2O/(CNa + CH2O)) was not significantly different. We conclude that renal denervation primarily affects the proximal tubule as manifested by a decrease in the reabsorption of sodium and water. A small effect of denervation on the distal nephron is not completely ruled out.