TONOMETRY REVISITED: PERFUSION-RELATED, METABOLIC, AND RESPIRATORY COMPONENTS OF GASTRIC MUCOSAL ACIDOSIS IN ACUTE CARDIORESPIRATORY FAILURE

Mucosal pH (pHi) is influenced by local perfusion and metabolism (mucosal-arterial Pco2 gradient, DeltaPco2), systemic metabolic acidosis (arterial bicarbonate), and respiration (arterial Pco2). We determined these components of pHi and their relation to outcome during the first 24 h of intensive care. We studied 103 patients with acute respiratory or circulatory failure (age, 63 +/- 2 [mean +/- SEM]; Acute Physiology and Chronic Health Evaluation II score, 20 +/- 1; Sequential Organ Failure Assessment score, 8 +/- 0). pHi, and the effects of bicarbonate and arterial and mucosal Pco2 on pHi, were assessed at admission, 6, and 24 h. pHi was reduced (at admission, 7.27 +/- 0.01) due to low arterial bicarbonate and increased DeltaPco2. Low pHi (<7.32) at admission (n = 58; mortality, 29% vs. 13% in those with pHi >/=7.32 at admission; P = 0.061) was associated with an increased DeltaPco2 in 59% of patients (mortality, 47% vs. 4% for patients with low pHi and normal DeltaPco2; P = 0.0003). An increased versus normal DeltaPco2, regardless of pHi, was associated with increased mortality at admission (51% vs. 5%; P < 0.0001; n = 39) and at 6 h (34% vs. 13%; P = 0.016; n = 45). A delayed normalization or persistently low pHi (n = 47) or high DeltaPco2 (n = 25) was associated with high mortality (low pHi [34%] vs. high DeltaPco2 [60%]; P = 0.046). In nonsurvivors, hypocapnia increased pHi at baseline, 6, and 24 h (all P perfusion and is associated with high mortality. Arterial bicarbonate contributes more to pHi than the DeltaPco2 but is not associated with mortality. Hyperventilation partly masks mucosal acidosis. Inadequate tissue perfusion may persist despite stable hemodynamics and contributes to poor outcome.

Pattern of regional cerebral blood-flow changes induced by acute heroin administration--a perfusion MRI study

Although both the subjective and physiological effects of abused psychotropic substances have been characterized, less is known about their effects on brain function. We examined the actions of intravenous diacetylmorphine (heroin), the most widely abused opioid, on regional cerebral blood flow (rCBF), as assessed by perfusion-weighted MR imaging (PWI) in a double-blind and placebo-controlled setting.

[Hypophyseal incidentaloma in a patient with autosomal dominant polycystic kidney disease]

The prevalence of incidentally discovered lesions within the pituitary (pituitary incidentalomas) is about 10%. The most common form of sellar mass are clinically nonfunctioning adenomas (less than 10 mm); functioning adenomas, however, are rare. Incidentally discovered pituitary microadenomas causing growth hormone hypersecretion are uncommon. In addition, the association of autosomal dominant polycystic kidney disease with acromegaly is exceptional and has not yet been reported to our knowledge.

Prevalence of cholecystolithiasis and its management among kidney/pancreas-transplanted type 1 (insulin-dependent) diabetic patients

BACKGROUND: Simultaneous pancreas/kidney transplantation (SPK) should be the procedure of choice for (pre)uremic patients with type 1 diabetes. All standard immunosuppressive protocols for SPK include a calcineurin-inhibitor. Both calcineurin inhibitors, cyclosporine (CyA) and probably tacrolimus (FK506) too, are associated with the occurrence of cholelithiasis due to their metabolic side effects. PATIENTS AND METHODS: We evaluated the prevalence of cholelithiasis in 83 kidney/pancreas transplanted type I-diabetic patients (46 males, 37 females, mean age 42.8 +/- 7.5 years) by conventional B-mode ultrasound 5 years after transplantation. 56 patients received CyA (group 1) and 27 received tacrolimus (group 2) as first-line-immunosuppressive drug. Additional immunosuppression consisted of steroids, azathioprine or mycophenolate mofetil. Additionally, laboratory analyses of cholestasis parameters (gamma-GT and alcalic phosphatasis) were performed. RESULTS: In total, 23 patients (28%) revealed gallstones and 52 patients (62%) revealed a completely normal gallbladder. In eight patients (10%) a cholecystectomy was performed before or during transplantation because of already known gallstones. No concrements in the biliary ducts (choledocholithiasis) could be detected. In group 2 the number of patients with gallstones was slightly lower (22%) compared with group 1 patients (30%), but without statistical significance. - Cholestasis parameters were not increased and HbA1c values were normal in both groups of patients. CONCLUSION: The prevalence of biliary disease in kidney/pancreas transplanted type I-diabetic patients with 28% is increased in comparison to the general population (10-15%). Lithogenicity under tacrolimus seems to be lower as under cyclosporine based immunosuppressive drug treatment. We recommend regular sonographical examinations to detect an acute or chronic cholecystis as early as possible, which may develop occultly in these patients.

[Changes in partner relationship after organ transplantation: comparison between heart, liver, and kidney transplantation]

AIM: This study was conducted to delineate partnership-relation functioning over time and specifically matched to various organs such as heart, liver, and kidney. METHOD: Prospective, paralleled case-control-study including patients and their respective partners before and one year after organ transplantation in 23 heart-transplant recipients, 19 liver-transplant patients, and 16 kidney-transplant recipients. To assess partnership functioning, the FB-Z (family assessment measure) of Cierpka and Frevert was used. Statistics included descriptive methods, correlations, and analysis of variance including the items "organ" and "time". RESULTS: Heart-transplant recipients and their partners show significant better overall measures in their partnership ratings (sum-value) in comparison to liver or kidney patients and their partners. In all patient and partner groups, except in kidney-transplant recipients a significant deterioration over time is discernible in the subscales role performance and emotionality. In respect to the item "organ" significant differences were found in overall functioning and the subscale communication where heart-transplant recipients and their partners have significant better functioning compared to kidney or liver transplant patients. In kidney patients and their partners only communication changes to the better in the time course. CONCLUSION: In any organ transplantation the two sides of the coin are important to bear in mind, the one is the live-saving act of transplantation as such, the other is the important distress in the phase before but equally after the operation, mainly in the first year where patients and their respective partners have to be followed and treated even in respect to psychosocial and marital functioning.

Functionally relevant coronary artery disease: comparison of 64-section CT angiography with myocardial perfusion SPECT

PURPOSE: To prospectively determine the accuracy of 64-section computed tomographic (CT) angiography for the depiction of coronary artery disease (CAD) that induces perfusion defects at myocardial perfusion imaging with single photon emission computed tomography (SPECT), by using myocardial perfusion imaging as the reference standard. MATERIALS AND METHODS: All patients gave written informed consent after the study details, including radiation exposure, were explained. The study protocol was approved by the local institutional review board. In patients referred for elective conventional coronary angiography, an additional 64-section CT angiography study and a myocardial perfusion imaging study (1-day adenosine stress-rest protocol) with technetium 99m-tetrofosmin SPECT were performed before conventional angiography. Coronary artery diameter narrowing of 50% or greater at CT angiography was defined as stenosis and was compared with the myocardial perfusion imaging findings. Quantitative coronary angiography served as a reference standard for CT angiography. RESULTS: A total of 1093 coronary segments in 310 coronary arteries in 78 patients (mean age, 65 years +/- 9 [standard deviation]; 35 women) were analyzed. CT angiography revealed stenoses in 137 segments (13%) corresponding to 91 arteries (29%) in 46 patients (59%). SPECT revealed 14 reversible, 13 fixed, and six partially reversible defects in 31 patients (40%). Sensitivity, specificity, and negative and positive predictive values, respectively, of CT angiography in the detection of reversible myocardial perfusion imaging defects were 95%, 53%, 94%, and 58% on a per-patient basis and 95%, 75%, 96%, and 72% on a per-artery basis. Agreement between CT and conventional angiography was very good (96% and kappa = 0.92 for patient-based analysis, 93% and kappa = 0.84 for vessel-based analysis). CONCLUSION: Sixty-four-section CT angiography can help rule out hemodynamically relevant CAD in patients with intermediate to high pretest likelihood, although an abnormal CT angiography study is a poor predictor of ischemia.

Effects of cerebral perfusion pressure and increased fraction of inspired oxygen on brain tissue oxygen, lactate and glucose in patients with severe head injury

OBJECTIVE: The purpose of the study was to measure the effects of increased inspired oxygen on patients suffering severe head injury and consequent influences on the correlations between CPP and brain tissue oxygen (PtiO2) and the effects on brain microdialysate glucose and lactate. METHODS: In a prospective, observational study 20 patients suffering severe head injury (GCS< or =8) were studied between January 2000 and December 2001. Each patient received an intraparenchymal ICP device and an oxygen sensor and, in 17 patients brain microdialysis was performed at the cortical-subcortical junction. A 6 h 100% oxygen challenge (F IO2 1.0) ( Period A) was performed as early as possible in the first 24 hours after injury and compared with a similar 6 hour period following the challenge ( Period B). Statistics were performed using the linear correlation analysis, one sample t-test, as well as the Lorentzian peak correlation analysis. RESULTS: F IO2 was positively correlated with PtiO2 (p < 0.0001) over the whole study period. PtiO2 was significantly higher (p < 0.001) during Period A compared to Period B. CPP was positively correlated with PtiO2 (p < 0.001) during the whole study. PtiO2 peaked at a CPP value of 78 mmHg performing a Lorentzian peak correlation analysis of all patients over the whole study. During Period A the brain microdialysate lactate was significantly lower (p = 0.015) compared with Period B. However the brain microdialysate glucose remained unchanged. CONCLUSION: PtiO2 is significantly positively correlated with F IO2, meaning that PtiO2 can be improved by the simple manipulation of increasing F IO2 and ABGAO2. PtiO2 is positively correlated with CPP, peaking at a CPP value of 78 mmHg. Brain microdialysate lactate can be lowered by increasing PtiO2 values, as observed during the oxygen challenge, whereas microdialysate glucose is unchanged during this procedure. Extension of the oxygen challenge time and measurement of the intermediate energy metabolite pyruvate may clarify the metabolic effects of the intervention. Prospective comparative studies, including analysis of outcome on a larger multicenter basis, are necessary to assess the long term clinical benefits of this procedure.

Sample preparation of culture medium from Madin-Darby canine kidney cells

A reproducible, standardized and simple sample preparation methodology is the key to successful two-dimensional gel electrophoresis (2-DE). This chapter describes step-by-step the sample preparation of culture medium from Madin-Darby canine kidney (MDCK) cells. Tips and tricks are given to circumvent possible pitfalls.

Metalloprotease meprin beta in rat kidney: glomerular localization and differential expression in glomerulonephritis

Meprin (EC 3.4.24.18) is an oligomeric metalloendopeptidase found in microvillar membranes of kidney proximal tubular epithelial cells. Here, we present the first report on the expression of meprin beta in rat glomerular epithelial cells and suggest a potential involvement in experimental glomerular disease. We detected meprin beta in glomeruli of immunostained rat kidney sections on the protein level and by quantitative RT-PCR of laser-capture microdissected glomeruli on the mRNA level. Using immuno-gold staining we identified the membrane of podocyte foot processes as the main site of meprin beta expression. The glomerular meprin beta expression pattern was altered in anti-Thy 1.1 and passive Heymann nephritis (PHN). In addition, the meprin beta staining pattern in the latter was reminiscent of immunostaining with the sheep anti-Fx1A antiserum, commonly used in PHN induction. Using Western blot and immunoprecipitation assays we demonstrated that meprin beta is recognized by Fx1A antiserum and may therefore represent an auto-antigen in PHN. In anti-Thy 1.1 glomerulonephritis we observed a striking redistribution of meprin beta in tubular epithelial cells from the apical to the basolateral side and the cytosol. This might point to an involvement of meprin beta in this form of glomerulonephritis.