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We report the case history of a 28-year-old homosexual man of Caucasian origin whose diagnosis of acquired immunodeficiency syndrome was established one year before admission on the basis of a positive human immunodeficiency virus serology and cutaneous Kaposi's sarcoma. Severe postprandial vomiting pointed to bowel obstruction in an emaciated, poor risk patient. Endoscopy revealed multifocal, violaceous tumours throughout the upper gastrointestinal tract which, eventually, obstructed the duodenum. Histology confirmed the putative diagnosis of gastrointestinal Kaposi's sarcoma, which responded well to monochemotherapy with vincristine. Significant clinical improvement and repeat endoscopy indicated tumour regression and resolution of bowel obstruction.

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Diverticular disease of the large bowel is very common in Western societies. The clinical pattern reaches from uncomplicated diverticular disease to acute peridiverticulitis, that ultimately afflicts about one in four patients having colonic diverticulosis. The illness may be indolent or fulminant, depending on the degree of colonic spillage and its containment. Therapy is usually medical and consists of "resting" the bowel, administering antibiotics and analgetics. Surgery is reserved for recurrent acute attacks, diffuse peritonitis, abscesses, fistulas, severe diverticular hemorrhage or obstruction. A diet rich in fibers reduces infectious complications.

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The incidence and prevalence of Crohn's disease (CD) and ulcerative colitis (UC) were investigated retrospectively for 1970-1980 and prospectively for 1981-1984 in the predominantly rural county of Tübingen (FRG). Eight hundred and twenty-eight patients with CD and 376 patients with UC were detected. Point prevalence at the end of 1984 was 54.6 for CD and 24.8 for UC, respectively. The occurrence of UC was stable during the period of investigation. The annual incidence of CD rose during the end of the seventies and afterwards reached a plateau of about 4 new cases per 100,000 inhabitants per annum. The prevalence of IBD was markedly greater in the cities than in the rural areas of the county.

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In rats several circadian rhythms such as heart rate, body temperature, and locomotor activity are known. Several authors found a loss of day-night-rhythm (locomotor activity, EEG) after portacaval shunting (PCA). The aim of this study was to evaluate whether muscle PO2 oscillations are circadian and whether they are altered after time-limited hypercirculation caused by PCA. 126 days after operation tissue PO2 of m. rectus abdominis of 9 rats with PCA and 10 controls was measured with a multi-wire surface electrode. All animals were kept under constant conditions and each animal was measured 6 times at intervals of 4 hours in order to get a circadian PO2 course. In controls the circadian course of mean muscle PO2 resembled a sine oscillation with high values at night and low values in the afternoon. In PCA-rats the time course of mean muscle PO2 showed 3 oscillations with different amplitudes, each with a period length of 24 hours. Our results indicate that oscillations of muscle PO2 are determined principal by circadian locomotor activity and that time-limited hypercirculation influences the circadian course of mean muscle PO2.

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Heparin is known to impair the antiaggregatory effectiveness of prostacyclin (PGI2) for adenosine diphosphate-induced aggregation in citrated platelet rich plasma. Thus porcine mucosal heparin (PMH) from different commercial sources was investigated for its ability to compete with specific platelet prostacyclin binding. In concentrations up to 250 IU/ml PMH itself did not interfere with the binding of 3 X 10(-9) M 9-3H-PGI2-sodium salt to intact washed platelets. The displacement of specifically bound PGI2 observed by PMH (Ki 60 IU/ml) containing 4-chloro-m-cresol (4-CC) was caused by the preservative (Ki 4-CC 3.0 X 10(-4) M). Although 60 IU/ml PMH (free of 4-CC) have been shown to inhibit basal 3 X 10(-5) M forskolin-, and 10(-8)M Iloprost-stimulated adenylate cyclase in platelet membranes (-63%, -62%, -83% respectively), no effect of PMH on 3H-cyclic-AMP formation has been observed when intact platelets were studied by 3H-adenine prelabeling technique. There is also no evidence that the preincubation of PGI2 (5 X 10(-7) M) with 1000 IU/ml PMH might neutralize the effectiveness of this eicosanoid. In contrast, PGI2 preincubated with PMH (10 min, 37 degrees C) caused a more pronounced increase of platelet 3H-cyclic AMP (+65%) compared with PGI2 incubated in 5 X 10(-2) M Tris-HCl, pH 7.4. Thus our data provide no evidence that PMH interferes with i) specific platelet PGI2 binding, ii) PGI2-stimulated cyclic AMP synthesis or iii) neutralizes PGI2 by formation of a biologically less active PGI2-PMH complex.

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Binding capacity (Bmax) and dissociation constant (KD) of platelet prostacyclin (PGI2) receptors in 23 male smokers and 14 nonsmokers have been determined by direct binding studies to investigate whether platelet prostacyclin binding is altered in smokers. In addition, the inhibitory effect of PGI2 (IC50) on adenosine diphosphate (ADP)-induced platelet aggregation was measured. As confirmed by discriminant analysis, 69% of the smokers had significantly different Bmax and KD. Binding capacity was increased in 12 smokers (Bmax + 74%), with a concomitant decrease in affinity (KD + 94%). In these volunteers, the postreceptor responses (PGI2-induced cyclic adenosine monophosphate [AMP] accumulation in platelet-rich plasma as well as IC50) did not differ from those of controls. In contrast, four smokers with considerably reduced PGI2 binding capacity (Bmax - 65%) exhibited a lower antiaggregatory effect (IC50 + 74%), although the affinity was slightly increased (KD - 61%). Nicotine, L-epinephrine, and prostaglandin E2 did not significantly compete with the binding of 9-3H-PGI2 sodium salt. The antiaggregatory effect of PGI2 on ADP-induced platelet aggregation, however, was inhibited by L-epinephrine (Ki 26 nmol/L) and prostaglandin E2 (Ki 230 nmol/L). Our data suggest that with respect to platelet PGI2 binding and in vitro responsiveness to PGI2, smokers are a heterogeneous population. Although increased binding capacity was observed in 50% of the smokers investigated, our data provide no evidence that a biologically relevant upregulation, for example with concomitant enhanced postreceptor reaction, occurs in smokers.

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The fatty acid composition of plasma and red cell membranes was determined in alcoholics without liver dysfunction upon admission for withdrawal therapy and after a 4-week period of abstinence, and in normal subjects. Fatty acid analysis of plasma by capillary gas chromatography showed a higher proportion of saturated fatty acids in alcoholics on admission than in normal subjects. Other major differences in plasma fatty acids in alcoholics were the reduction of linoleic acid and the increase in palmitic acid. Similar abnormalities were measured in red cell membranes of alcoholics. Although there were less polyunsaturated fatty acids in red cells of alcoholics, the degree of hydrogen peroxide or phenylhydrazine-induced lipid peroxidation was the same as in controls. Membrane tolerance to ethanol was attributed to adaptive membrane alterations (increase of saturated fatty acids in membranes). However, the here reported changes in plasma and red cell lipids suggest that alterations in red cell membrane lipids reflect abnormalities in plasma lipids due to equilibrium exchanges rather than signify adaptive changes of the red cells to ethanol.

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In a prospective study the detection rate of stenoses and occlusions of extracranial arteries by continuous-wave (CW) Doppler sonography, duplex-scan and selective angiography was compared independently by three investigators. In 89 patients (488 arteries) CW-Doppler sonography was superior to duplex-scan in the detection of stenoses exceeding 50% and occlusions. Duplex-scan detected about half of low degree stenoses and arteriosclerotic plaques and in some cases lesions which are not shown in angiography. Thus, Doppler sonography and duplex-scan are complementary rather than competitive methods. Doppler sonography is necessary for the evaluation of flow disturbances in the vertebral and subclavian arteries and high degree stenoses in the intracranial section of the internal carotid artery.

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PIP: Arachidonic acid (AA) concentration in platelet lipids is known to be altered by the intake of oral contraceptives (OCs). Conflicting results have been reported on the influence of OCs on eicosanoid metabolism in platelets. The metabolism of exogenous 14-C-AA in platelets and synthesis of TXB2 from endogenous AA sources under OC medication was investigated. The antiaggregatory potency of prostacyclin also was determined. Citrated PRP from healthy women without and with intake of OCs was investigated (low dose estrogen 54%, medium dose 33%, high dose 13%, combined with various preparations). Age, smoking habits, and hematocrit values were comparable in both groups. Metabolism of exogenous 14-C-AA was determined in gel-filtered platelets. Metabolities were separated by thin layer chromatography. Synthesized TXB2 from endogenous AA sources was measured by radioimmunoassay after collagen-induced aggregation. Therewas no influence of OC intake on metabolism of exogenous AA in platelets. No increase in 12-HETE levels under combined estrogen/progestogen medication was observed, which may be due to the antiestrogenic effect of progestogens. OC intake causes a slight decrease of TXB2 synthesis from endogenous sources without changing platelet aggregability measured in citrated PRP. In contrast to earlier findings, these data do not indicate reduced antiagregatory potency of prostacyclin in women taking OCs. The results suggest that the observed increase in platelet reactivity ex vivo cannot be explained by changes in AA metabolism. Changes of plasmatic coagulation and consecutive activation of platelets may be an alternative explanation.^ieng

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