Biomedical subjects

K Schwarting

Publications and source records attributed to K Schwarting.

8 recordsLinked to original sources

PubMed1999

Mucosal cytokine expression, cellular markers and adhesion molecules in inflammatory bowel disease.

OBJECTIVE: To relate proinflammatory cytokines to leukocyte surface markers and adhesion molecules in the same paraffin-embedded biopsy specimen in inflammatory bowel disease (IBD) of varying activity. METHODS: Biopsies of seven cases of Crohn's disease, seven patients with ulcerative colitis, one case of intestinal infection and six control subjects were studied. We performed in situ hybridization on sections of tissue using probes specific to interleukin-1beta (IL-1beta), interleukin-6 (IL-6) and tumour necrosis factor-alpha (TNF alpha). Leucocyte markers and adhesion molecules were investigated in subsequent slides of selected specimens by immunohistochemistry. RESULTS: Cytokine mRNA was found in large numbers of cells throughout the inflamed intestine but also in some macroscopically unaffected tissue specimens. Transcripts were predominantly located within the lamina propria where immunohistochemistry of parallel sections revealed numerous macrophages and the presence of endothelial adhesion molecules. The expression of the different cytokines was closely related to each other and to histological but not to macroscopic (endoscopic) activity. CONCLUSIONS: The synthesis of IL-1beta IL-6 and TNF alpha mRNA is coordinately regulated. Cytokine production is located mostly in the lamina propria at sites that are rich in macrophages and show abundant staining of vascular adhesion molecules. This cascade of immune events is related to inflammatory cell infiltration in both Crohn's disease and ulcerative colitis.

Adult↗

PubMed1999

Mesenteric blood flow is related to disease activity and risk of relapse in Crohn's disease: a prospective follow-up study.

OBJECTIVE: The diagnostic significance of increased splanchnic blood flow in Crohn's disease is unclear. This prospective study was therefore undertaken to define the role of Doppler sonography in the assessment of disease activity and in the prediction of early relapse. METHODS: Splanchnic flowmetry was performed in 59 patients with Crohn's disease and 20 healthy volunteers during fasting and 30 min after ingestion of a standardized meal. Twenty-one patients measured during the active state and in clinical remission were followed-up for 6 months. Hemodynamic parameters of the superior and inferior mesenteric arteries and the portal vein were related to clinical (Crohn's disease activity index [CDAI]), laboratory (C-reactive protein), and endoscopic (Crohn's Disease Endoscopic Index of Severity) parameters of disease activity. RESULTS: The postprandial mean velocity of the superior mesenteric artery correlated closest with clinical activity (CDAI, p < 0.005) and C-reactive protein (p < 0.01), but was unrelated to endoscopic activity. All patients in remission after 6 months (9/9) showed an increase in postprandial pulsatility index of the superior mesenteric artery, compared with an initial measurement during active disease (+28%). In contrast, the majority of patients with later relapse or surgery (11/12) had decreased pulsatility index during initial remission (-20%). The positive predictive value of this index for maintenance of remission was 0.82. CONCLUSIONS: Postprandial flow measurements in the superior mesenteric artery are closely related to clinical but not endoscopic disease activity in patients with Crohn's disease. The repeated measurement of the postprandial pulsatility index allows estimation of the risk of recurrence.

Adult↗

PubMed1999

Mesenteric blood flow is related to disease activity and risk of relapse in ulcerative colitis: a prospective follow up study.

BACKGROUND: The diagnostic significance of increased splanchnic blood flow in ulcerative colitis is unclear. This prospective study was therefore undertaken to define the role of Doppler sonography in the assessment of disease activity and in the prediction of early relapse. SUBJECTS/METHODS: Splanchnic flowmetry was performed in 76 patients with ulcerative colitis (47 with active disease and 29 in remission), six with infectious colitis, and 13 healthy controls during fasting and 30 minutes after ingestion of a standardised meal. Twenty seven of the patients with ulcerative colitis and all patients with infectious colitis were investigated during the active state as well as in clinical remission and followed up for six months. Flow velocity and pulsatility index (PI) of the superior (SMA) and inferior (IMA) mesenteric arteries and the portal vein were related to clinical (Truelove index), laboratory (C-reactive protein), and endoscopic (Sutherland index) parameters of disease activity. RESULTS: The mean flow velocity of the IMA correlated closest with clinical activity (Truelove, r = 0.41, p<0.005), the PI with C-reactive protein (r = 0.30, p<0.05), and endoscopic activity (r = 0.45, p<0.001). All patients in remission after six months (14/14) or with infectious colitis (6/6) showed an increase in PI of the IMA compared with the initial measurement during active disease (mean increase for ulcerative colitis +36% and for infectious colitis +77%). In contrast, most patients with later relapse or surgery (11/13) had decreased PI during initial remission (mean decrease -12%). The positive predictive value of this index for maintenance of remission was 0.77. Flow variables of the SMA and portal vein displayed weaker correlations. CONCLUSIONS: Flow measurements in the IMA are closely related to clinical and endoscopic disease activity in patients with ulcerative colitis. Repeated measurement of the PI allows estimation of the risk of recurrence.

Adolescent↗

PubMed1998

The postprandial portal flow is related to the severity of portal hypertension and liver cirrhosis.

BACKGROUND/AIMS: Diminished postprandial portal hyperemia has been demonstrated by echo-Doppler flowmetry in patients with liver cirrhosis, but its diagnostic role is unclear. This prospective study was therefore undertaken in patients with varying severity of portal hypertension and degree of liver cirrhosis. METHODS: Portal flowmetry was performed in 66 patients with cirrhosis and 20 healthy volunteers during fasting and 30 min after ingestion of a standardized meal. Hemodynamic parameters were related to the degree of esophageal varices, variceal bleeding, portal hypertensive gastropathy and Child-Pugh score. RESULTS: The postprandial portal blood velocity increment was low in patients with esophageal varices of any degree (22-24%), compared to patients without varices (49%, p<0.01) and healthy controls (65%, p<0.001), but was not different in patients with or without variceal bleeding (22% vs. 20%). In contrast, the congestion index (CI; ratio of portal vein cross-sectional area and portal blood velocity) pre-/postprandial decreased in the bleeding group only (CI pre/ CI post 1.30+/-0.23 (no bleeding) vs. 0.86+/-0.29 (bleeding); p<0.01). Portal hypertensive gastropathy was not related to any of the portal flow parameters. The portal blood velocity increment was comparable in controls (65%) and patients with Child-Pugh class A cirrhosis (56%), but lower in patients with class B (32%) and class C cirrhosis (15%, p<0.05 vs. class A). Also, there was no postprandial decrease in congestion index in patients with the most severe cirrhosis (p<0.01 class C vs. class A and B). CONCLUSIONS: The postprandial rise in portal flow is inversely related to the severity of portal hypertension and liver cirrhosis, and may be a valuable parameter with respect to the risk of variceal bleeding.

Adult↗

PubMed1997

Renal endothelin system in obstructive jaundice: its role in impaired renal function of bile-duct ligated rats.

1. Obstructive jaundice predisposes the kidney to acute renal failure. Endothelin (ET), a potent renal vasoconstrictor and modulator of the tubular action of arginine vasopressin, has been suggested to play a pathogenetic role in acute renal failure. In the present study we therefore investigated renal function and the renal ET system in rats on day 4 after bile-duct ligation (BDL) or sham-operation (SO), without (n = 7 in each group) and with treatment with bosentan, a combined ETA/ETB receptor blocker, (n = 5 in each group). 2. On day 4 after BDL, serum bilirubin had increased to 226 +/- 10 mumol/l (SEM) as compared with 6 +/- 2 mumol/l in SO rats. Endogenous creatinine clearance, an index of glomerular filtration rate, was significantly reduced to 0.7 +/0 0.1 ml min-1 g-1 of kidney weight after BDL as compared with 1.1 +/- 0.1 ml min-1 g-1 of kidney weight after SO (P < 0.05). Bosentan prevented the decrease in glomerular filtration rate (1.0 +/- 0.2 ml min-1 g-1 of kidney weight), as well as polyuria and defective concentrating ability, in BDL rats. 3. Plasma ET concentration on day 4 after surgery (28.2 +/- 1.5 pmol/l) was higher (P < 0.01) in BDL than in SO rats (12.9 +/- 1.5 pmol/l) and rose further in bosentan-treated BDL and SO rats (43.4 +/- 5.1 compared with 21.9 +/- 6.6 pmol/l). Urinary ET excretion was significantly higher in BDL rats than in SO rats (1.58 +/- 0.22 compared with 1.28 +/- 0.18 pmol 24 h-1 100 g-1 of body weight; P < 0.05). 4. ET synthesis by glomeruli isolated from BDL rats was lower [81 +/- 19 fmol h-1 (mg of protein)-1] than that from SO-rats [139 +/- 28 fmol h-1 (mg of protein)-1; P < 0.05], whereas papillary ET synthesis was higher in BDL [10 +/- 3 fmol h-1 (mg of protein)-1] than in SO rats [4 +/- 1 fmol h-1 (mg of protein)-1; P < 0.05]. 5. The results indicate that BDL is associated with increased plasma ET concentration and suppression of GFR. Enhanced renal inner medullary collecting-duct ET synthesis, which is reflected by increased urinary ET excretion, may reduce distal tubular water absorption in BDL rats. Increased circulating and renal papillary ET synthesis may thus contribute to renal dysfunction and predispose the kidney to acute renal failure in obstructive jaundice.

Acute Kidney Injury↗

PubMed1995

Impaired renal function in obstructive jaundice: enhanced glomerular thromboxane synthesis and effects of thromboxane receptor blockade in bile duct-ligated rats.

1. Patients with obstructive jaundice are especially susceptible to acute renal failure. We have previously observed that in rats with bile duct ligation impaired renal function is associated with increased urinary thromboxane excretion. 2. In the present study we therefore investigated, in rats with bile duct ligation, renal function, urinary thromboxane excretion and thromboxane B2 synthesis by isolated glomeruli as well as the effects of the thromboxane A2/prostaglandin H2 receptor antagonist Daltroban on renal function in rats with bile duct ligation as compared with sham-operated rats. 3. On the fourth day after bile duct ligation (n = 7 rats) endogenous creatinine clearance as an estimate of glomerular filtration rate was significantly reduced to 0.74 +/- 0.05 (SEM) as compared with 1.06 +/- 0.09 ml min-1 g-1 kidney weight in sham-operated rats (n = 7, P < 0.01). In rats with bile duct ligation, urine volume was slightly increased, whereas urinary sodium (Na+) (P < 0.001) and potassium (K+) (P < 0.01) excretion as well as urine osmolarity (P < 0.05) were significantly reduced and lower than in sham-operated rats. 4. Urinary thromboxane excretion was significantly higher in rats with bile duct ligation than in sham-operated rats: 116.6 +/- 22.3 versus 56.8 +/- 10.2 pmol 24 h-1 100 g-1 body weight (P < 0.05). Thromboxane B2 synthesis in glomeruli isolated from rats with bile duct ligation was also significantly higher than in sham-operated rats: 12.6 +/- 2.0 versus 6.4 +/- 0.9 pmol h-1 mg-1 protein (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Kidney Injury↗

PubMed1987

[Right ventricular endomyocardial fibrosis].

The clinical course, non-invasive and invasive diagnostic findings from a 50-year-old patient with endomyocardial fibrosis are reported. The patient died in cardiogenic shock. In Europe, endomyocardial fibrosis is a rare event. An exclusively right ventricular involvement is a seldom manifestation. The clinical, echocardiographic and computed tomographic features are diagnostic; therefore a satisfactory differentiation from other cardiac disorders with restrictive hemodynamic signs is possible. An echodense mass as cavity obliteration, with predominantly apical localization, was present at echocardiography; the computed tomography showed a hypodense area instead of the right ventricular cavity.

Echocardiography↗

PubMedDate not supplied

Cytokine expression in intestinal mucosal biopsies. In situ hybridisation of the mRNA for interleukin-1 beta, interleukin-6 and tumour necrosis factor-alpha in inflammatory bowel disease.

Etiology and pathogenesis of inflammatory bowel disease (IBD) remain obscure. There is substantial evidence that proinflammatory cytokines such as Interleukin-1 beta (IL-1 beta), Interleukin-6 (IL-6) and Tumour Necrosis Factor-alpha (TNF-alpha) exhibit a key role in the the inflammatory process. In situ hybridisation can depict individual cells producing cytokine mRNA. We performed hybridisation with antisense probes specific for IL-1 beta, IL-6 and TNF-alpha on sections of paraffine-embedded biopsies. Specimens obtained from three control persons and six cases of Crohn's disease (CD) were investigated. Only few positive cells were found in tissue sections of control persons, clusters of lamina propria cells or epithelial cells containing cytokine mRNA were not observed. Inflammatory bowel disease tissue contained large numbers of cells producing mRNA specific for the three proinflammatory cytokines assayed. IL-1 beta, IL-6 and TNF-alpha mRNA were predominantly detected corresponding to cells of the lamina propria. Single cells containing mRNA specific for IL-6 were also found among the epithelial lining of intestinal crypts. Epithelial cells containing IL-1 beta and IL-6 mRNA were found in specimens derived from one patient with Crohn's disease. Notably, large amounts of cells containing cytokine mRNA were not only found in inflamed, but also in macroscopically normal mucosa. In conclusion, using proinflammatory cytokines as a model, we established in situ hybridisation on sections of mucosal biopsies permitting further insight into immune activation at individual cell level.

Biopsy↗