Extracellular fluid volume: A suitable indexation variable to assess impact of bariatric surgery on glomerular filtration rate in patients with chronic kidney disease.

BACKGROUND: Bariatric surgery (BS) might be a nephroprotective treatment in obese patients with chronic kidney disease (CKD), and the non-linear relation between body surface area (BSA) and extracellular fluid volume (ECFV) in obese people raises the question of the most relevant way to scale glomerular filtration rate (GFR) for assessing renal function changes after BS. METHODS: We screened 1774 BS candidates and analysed 10 consecutive participants with CKD stage 3. True GFR (mGFR), measured by the renal clearance of 51Cr-ethylenediaminetetraacetic acid (EDTA), was scaled either to BSA (mGFRBSA) or to ECFV measured by 51Cr-EDTA distribution volume (mGFRECFV) before and one year after BS. RESULTS: The 10 candidates for BS had a mean body mass index of 43.3 ± 3.6 kg/m2 and a mean GFR of 48 ± 8 mL/min/1.73 m2. Six participants had a sleeve gastrectomy and four had a Roux-en-Y gastric bypass. One year after BS, ECFV decreased (23.2 ± 6.2 to 17.9 ± 4.3 L, p = 0.001), absolute mGFR was not significantly modified (74 ± 23 versus 68 ±19 mL/min), mGFRBSA did not change significantly (53 ± 18 versus 56 ± 17 mL/min/1.73 m2) whereas mGFRECFV significantly increased (42 ± 13 versus 50 ± 14 mL/min/12.9 L, p = 0.037). The relation between mGFRECFV and mGFRBSA was different from the identity line before (p = 0.014) but not after BS (p = 0.09). CONCLUSION: There is a difference between mGFRBSA and mGFRECFV following BS and the latter might better reflect the adequacy between renal function and corpulence.

Postoperative Renal Function in Patients Undergoing Unilateral Nephrectomy: Development of a Prediction Model Using Preoperative Risk Factors and 51Cr-EDTA Clearance.

Objectives: To analyze the preoperative variables associated to the postoperative glomerular filtration rate (GFR) outcomes after nephrectomy for benign and malignant conditions, measured by the reference isotopic technique 51Cr-ethylene diamine tetra-acetic (51Cr-EDTA) and to create a model to predict the short-term postoperative GFR. Secondary aim was to evaluate which of the common equations for GFR estimation (Cockcroft-Gault, Modification of Diet in Renal Disease [MDRD] or Chronic Kidney Disease Epidemiology Collaboration [CKD-EPI]) has the best correlation with the 51Cr-EDTA. Methods: Patients undergoing unilateral nephrectomy from 2014 to 2018 were selected. Pre- and postoperative variables were prospectively collected. Univariate and multivariate analyses were done to identify independent risk factors associated with renal function outcomes and to create a model to predict the postoperative GFR. Correlation analyses were performed to evaluate the performance of various serum creatinine-based equations for GFR estimation compared with 51Cr-EDTA. Results: In total, 107 patients were evaluated. After univariate and multivariate analyses, older age (p = 0.008), higher split function of the operated kidney on dimercaptosuccinic acid (DMSA) scintigraphy (p < 0.001), and lower preoperative 51Cr-EDTA (p < 0.001) were independent risk factors for higher GFR decline. Correlation analyses showed that GFR estimated by CKD-EPI equation had the best concordance to GFR measured by 51Cr-EDTA. Conclusions: Based on our findings age, DMSA and lower preoperative 51Cr-EDTA are predictors of postoperative renal function after unilateral nephrectomy. For the assessment of estimated GFR, CKD-EPI equation appears to have the best concordance with 51Cr-EDTA.

Intestinal permeability after Mediterranean diet and low-fat diet in non-alcoholic fatty liver disease.

BACKGROUND: In non-alcoholic fatty liver disease (NAFLD), a high-fat or high-fructose diet increases intestinal permeability and promotes derangement of the gut-liver axis. We hypothesize that, diet could be able to modulate intestinal permeability in patients with NAFLD. AIM: To detect diet-induced modification of intestinal permeability in patients with NAFLD undergoing a Mediterranean diet or a low-fat diet. METHODS: The current study was a dietary intervention for non-diabetic, patients with biopsy-verified NAFLD and increased transaminases. A crossover design was employed: participants underwent 16 weeks of Mediterranean diet, 16 wk of free wash-out, and 16 weeks of low-fat diet. Both diets were hypocaloric and no consumption of supplements was allowed. All patients were followed bimonthly by a dietitian. Evaluations of clinical and metabolic parameters were completed at baseline and at the end of each dietary period. Intestinal permeability was assessed by chromium-51 ethylene diamine tetraacetate excretion testing (51Cr-EDTA). RESULTS: Twenty Caucasian patients, 90% male, median age 43 years, body mass index (BMI) 30.9, with biopsy-verified NAFLD were enrolled. At the end of 16 weeks of a Mediterranean diet, a significant reduction in mean body weight (-5.3 ± 4.1 kg, P = 0.003), mean waist circumference (-7.9 ± 4.9 cm, P = 0.001), and mean transaminase levels [alanine aminotransferase (ALT) -28.3 ± 11.9 IU/L, P = 0.0001; aspartate aminotransferase (AST) -6.4 ± 56.3 IU/L, P = 0.01] were observed. These benefits were maintained after 16 wk of wash-out and also after 16 wk of low-fat diet, without further improvements. Fourteen of the 20 patients had intestinal permeability alteration at baseline (mean percentage retention of 51Cr-EDTA = 5.4%), but no significant changes in intestinal permeability were observed at the end of the 16 wk of the Mediterranean diet or 16 wk of the low-fat diet. CONCLUSION: Mediterranean diet is an effective strategy for treating overweight, visceral obesity and serum transaminase in patients with NAFLD. If the Mediterranean diet can improve intestinal permeability in patients with NAFLD, it deserves further investigation.

Gut Barrier Dysfunction-A Primary Defect in Twins with Crohn's Disease Predominantly Caused by Genetic Predisposition.

Background and Aims: The aetiology of Crohn's disease is poorly understood. By investigating twin pairs discordant for Crohn's disease, we aimed to assess whether the dysregulated barrier represents a cause or a consequence of inflammation and to evaluate the impact of genetic predisposition on barrier function. Methods: Ileal biopsies from 15 twin pairs discordant for Crohn's disease [monozygotic n = 9, dizygotic n = 6] and 10 external controls were mounted in Ussing chambers to assess paracellular permeability to 51Chromium [Cr]-EDTA and trancellular passage to non-pathogenic E. coli K-12. Experiments were performed with and without provocation with acetylsalicylic acid. Immunofluorescence and ELISA were used to quantify the expression level of tight junction proteins. Results: Healthy co-twins and affected twins displayed increased 51Cr-EDTA permeability at 120 min, both with acetylsalicylic acid [p < 0.001] and without [p < 0.001] when compared with controls. A significant increase in 51Cr-EDTA flux was already seen at 20 min in healthy monozygotic co-twins compared with controls [p≤0.05] when stratified by zygosity, but not in healthy dizygotic co-twins. No difference in E. coli passage was observed between groups. Immunofluorescence of the tight junction proteins claudin-5 and tricellulin showed lower levels in healthy co-twins [p < 0.05] and affected twins [p < 0.05] compared with external controls, while ELISA only showed lower tricellulin in Crohn's disease twins [p < 0.05]. Conclusion: Our results suggest that barrier dysfunction is a primary defect in Crohn's disease, since changes were predominantly seen in healthy monozygotic co-twins. Passage of E. coli seems to be a consequence of inflammation, rather than representing a primary defect.

Determination of optimal sampling times for a two blood sample clearance method using (51)Cr-EDTA in cats.

Estimation of the glomerular filtration rate (GFR) is a useful tool in the evaluation of kidney function in feline medicine. GFR can be determined by measuring the rate of tracer disappearance from the blood, and although these measurements are generally performed by multi-sampling techniques, simplified methods are more convenient in clinical practice. The optimal times for a simplified sampling strategy with two blood samples (2BS) for GFR measurement in cats using plasma (51)chromium ethylene diamine tetra-acetic acid ((51)Cr-EDTA) clearance were investigated. After intravenous administration of (51)Cr-EDTA, seven blood samples were obtained in 46 cats (19 euthyroid and 27 hyperthyroid cats, none with previously diagnosed chronic kidney disease (CKD)). The plasma clearance was then calculated from the seven point blood kinetics (7BS) and used for comparison to define the optimal sampling strategy by correlating different pairs of time points to the reference method. Mean GFR estimation for the reference method was 3.7+/-2.5 ml/min/kg (mean+/-standard deviation (SD)). Several pairs of sampling times were highly correlated with this reference method (r(2) > or = 0.980), with the best results when the first sample was taken 30 min after tracer injection and the second sample between 198 and 222 min after injection; or with the first sample at 36 min and the second at 234 or 240 min (r(2) for both combinations=0.984). Because of the similarity of GFR values obtained with the 2BS method in comparison to the values obtained with the 7BS reference method, the simplified method may offer an alternative for GFR estimation. Although a wide range of GFR values was found in the included group of cats, the applicability should be confirmed in cats suspected of renal disease and with confirmed CKD. Furthermore, although no indications of age-related effect were found in this study, a possible influence of age should be included in future studies.

[Monitoring renal function in patients treated with cytostatics]. / Måling af nyrefunktion under cytostatisk behandling.

INTRODUCTION: Some cytostatics, used in the treatment of cancer, are excreted by the kidneys and may be nephrotoxic. The glomerular filtration rate (GFR) represents a method for reliable assessement of the 51Cr-EDTA plasma clearance before and during treatment with nephrotoxic drugs. The aim of this retrospective study was to evaluate whether this method could be replaced by a more simplified GFR estimate calculated from the creatinine plasma concentration. MATERIALS AND METHODS: We included all patients who had had at least four GFR measurements in 2005 as part of their nephrotoxic cytostatic treatment. The estimated GFR (eGFR) was calculated from sex, age and weight, according to the Cockcroft formula. RESULTS: Forty-eight patients with a mean age of 47 years were included. 51Cr-EDTA plasma clearance and eGFR showed a poor correlation (r(2) = 0,678). On average, GFR decreased from 95 ml/min to 80 ml/min from the first to the fourth measurement, whereas plasma concentration of creatinine and eGFR remained unchanged. In 13 patients (27%), the treatment dose was reduced due to a fall in GFR. Seven of these 13 patients would have continued their treatment unchanged, if the clinical decision had been based on eGFR. CONCLUSION: Neither creatinine plasma concentration nor estimated GFR ad modum Cockcroft can be recommended for measurement of GFR in patients treated with nephrotoxic cytostatics.

Measurement of the kidney function in patients with rheumatoid arthritis: plasma cystatin C versus 51Cr-EDTA clearance.

BACKGROUND/AIM: Knowledge of the usefulness of cystatin C measurement in the detection of chronic kidney disease in patients with rheumatoid arthritis (RA) is scant. The purpose of this study was to evaluate the ability of plasma cystatin C- and creatinine-based methods to predict glomerular filtration rate (GFR) and classify chronic kidney disease in RA patients. METHODS: The study population consisted of 64 RA patients aged 41-86 years. Comparisons were made between measured plasma creatinine, cystatin C, creatinine clearance and GFR estimated by the Cockcroft-Gault (CG) and the Modification of Diet in Renal Disease (MDRD) formulas. The plasma clearance of (51)Cr-EDTA served as a reference. RESULTS: The Pearson correlation coefficients between plasma clearance of (51)Cr-EDTA and the markers of GFR were calculated. The correlation coefficients were 0.800 for plasma creatinine, 0.863 for cystatin C, 0.866 and 0.904 for GFR values estimated by MDRD and CG and 0.922 for plasma creatinine clearance. Statistically significant differences were detected between the correlation coefficients of plasma creatinine and GFR estimated by CG (p = 0.0412) and plasma creatinine and creatinine clearance (p = 0.0099). Creatinine clearance and the MDRD and CG formulas proved to be better at identifying GFR <90 ml/min than plasma creatinine or cystatin C. CONCLUSION: We recommend using the CG formula or creatinine clearance for the estimation of the GFR of RA patients instead of solely creatinine or cystatin C in clinical work.

Short-term distribution of Cs in relation to Cr-EDTA after intravenous dose in goats.

AIM: The aim of this study was to gather information about the short-term rate of caesium uptake (incorporation) in different animal tissues and explain them with known physiological mechanisms affecting ion distribution. METHODS: Six goats were given an intravenous bolus containing (134)Cs as a tracer and (51)Cr-EDTA as an extracellular marker. After 30 min, the animals were killed and the activity concentration of radioactive isotopes in different tissues and fluid compartments were measured. RESULTS: The highest relative activity concentration of (134)Cs was found in kidney cortex, with a tissue/plasma-ratio around 50. In urine, the ratio varied between 5 and 28. In the salivary gland, cardiac muscle and small intestine the ratio was around 11, 7 and 6, respectively. The contents of small intestine had an average activity concentration five times that of plasma. In skeletal muscle the terminal activity concentration was surprisingly low, with a tissue/plasma ratio mostly far less than unity. Even in connective tissue and cartilage the terminal activity concentration was generally higher than in skeletal muscle. CONCLUSION: The rate of uptake of caesium varies widely from tissue to tissue. Many of these differences can be explained with differences in Na,K-ATPase activity. Also, perfusion and accessibility play a role in some tissues, like brain and possibly part of the skeletal muscles. The short-term distribution of caesium differs distinctly from the long-term distribution reported in literature.

An acute stressor enhances sensitivity to a chemical irritant and increases 51CrEDTA permeability of the colon in adult rats.

We investigated the effect of prior acute stress on colonic permeability induced by a chemical irritant known to induce symptoms similar to inflammatory bowel disease in rodents. Adult male rats (n = 12) were stressed by a single session of ten unpredictable, uncontrollable foot shocks, and half were home cage controls (n = 12). Twenty-nine days later, half of each treatment group was exposed to 4% DSS (dextran sulphate sodium) solution in their drinking water for 48 hours while half received pure water over two periods separated by 17 days. After food deprivation overnight and light isoflurane anaesthesia the following morning, the animals were given a colonic infusion of 2000 nCi (nanocurie) 51CrEDTA (51Cr-labelled ethylenediaminetetraacetic acid) and then placed individually in metabolic cages for a six hours continuous urine collection. Radioactivity in urine was measured by a gamma counter and percentage recovery of 51CrEDTA calculated as an indicator of colonic mucosal permeability. Results concluded that pre-shocked animals exposed to DSS showed significantly higher mucosal permeability than the pre-shocked animals given water, and the non-shocked animals given either DSS or water. Pre-shock in combination with two exposures to a chemical irritant separated by 17 days had a pronounced effect on colonic permeability, indicating that stress should be considered a possible initiating or contributory factor to increased intestinal permeability related to a mucosal challenge.

A direct in vivo measurement of 99mTc-methylene diphosphonate protein binding.

Quantitative studies of the kinetics of 99mTc-methylene diphosphonate (99mTc-MDP) in metabolic and metastatic bone disease require the measurement of free tracer in plasma to derive the input function. We describe a simple method of determination of free 99mTc-MDP in vivo based on measurements of the ratio of the renal plasma clearances of total 99mTc-MDP and 51Cr-ethylenediaminetetraacetic acid (51Cr-EDTA). The method is based on evidence that free MDP is cleared through the kidneys by glomerular filtration. Measurements of the fraction of free 99mTc-MDP were made between 0 and 4 h after injection in 70 postmenopausal women enrolled in a study of the effect of hormone replacement therapy on the whole-skeleton plasma clearance of 99mTc-MDP (K(bone)). The glomerular filtration rate (GFR) was measured simultaneously from the plasma clearance of 51Cr-EDTA. The mean fractions (and SD) of free MDP measured were 0.757 (0.050), 0.663 (0.062), 0.550 (0.052) and 0.472 (0.053), respectively, at 17, 90, 150 and 210 min after injection. The results agreed closely with data using protein precipitation with trichloroacetic acid. Between 2 and 4 h after injection, the biological half-life of free 99mTc-MDP in plasma was 92 min, compared with 540 min for bound MDP. Highly significant relationships were found between the fraction of free MDP measured in each patient at each of the four time points and the total plasma clearance of free 99mTc-MDP (K(total)=GFR+K(bone)), such that a larger value of K(total) was associated with a smaller fraction of free MDP. Multivariate regression analysis confirmed that this relationship held individually for both GFR and K(bone). A strong inverse relationship was found between K(total) and the plasma concentration of free 99mTc-MDP, but a much weaker relationship with the bound MDP concentration, a finding that is consistent with the slow re-equilibration of bound MDP in the circulation. The results confirm that the fraction of free 99mTc-MDP varies with time and shows significant differences between individuals, which are dependent on GFR and K(bone) amongst other factors.

Intestinal permeability in strongyloidiasis

The objective of the present study was to assess intestinal permeability in patients with infection caused by Strongyloides stercoralis. Twenty-six patients (16 women and 10 men), mean age 45.9, with a diagnosis of strongyloidiasis were evaluated. For comparison, 25 healthy volunteers (18 women and 7 men), mean age 44.9, without digestive disorders or intestinal parasites served as normal controls. Intestinal permeability was measured on the basis of urinary radioactivity levels during the 24 h following oral administration of chromium-labeled ethylenediaminetetraacetic acid (51Cr-EDTA) expressed as percentage of the ingested dose. The urinary excretion of 51Cr-EDTA was significantly reduced in patients with strongyloidiasis compared to controls (1.60 + or - 0.74 and 3.10 + or - 1.40, respectively, P = 0.0001). Intestinal permeability is diminished in strongyloidiasis. Abnormalities in mucus secretion and intestinal motility and loss of macromolecules could explain the impaired intestinal permeability

Intracavitary administration: pharmacokinetic advantages of macromolecular anticancer agents against peritoneal and pleural carcinomatoses.

BACKGROUND: Pleural and peritoneal carcinomatoses are quite difficult to control in patients with advanced cancer. We have devised a suitable formulation of anticancer agents to be injected by the intracavitary route. MATERIALS AND METHODS: The pharmacokinetics of macromolecular anticancer agent, copoly(styrene/maleic acid)-conjugated neocarzinostatin (smancs) and radiolabeled albumin were studied after intraperitoneal administration to ascitic tumor-bearing rats and mice, and were compared with the pharmacokinetics of other low-molecular-weight anticancer agents, mitomycin C (MMC) and doxorubicin (DOX). RESULTS: Pharmacokinetic analyses indicated that smancs showed a much higher drug concentration for a longer time in the peritoneal cavity, and a much lower drug concentration in the blood circulation than did MMC or DOX. The cavity/blood ratios of the area under the concentration curve (AUC), of smancs, bovine serum albumin (BSA), DOX, and MMC were 9.69, 7.06, 1.38, 1.15, respectively. CONCLUSION: These results suggest that macromolecular agents are cleared more slowly from the cavitary compartment and remain there at a high concentration while the blood concentration remains low.

Interaction between neurokinin A, VIP, prostanoids, and enteric nerves in regulation of duodenal function.

Neurokinin A (NKA) induces duodenal motility and increases mucosal permeability and bicarbonate secretion in the in situ perfused duodenum in anesthetized rats. In the present study, the NKA-induced increase in mucosal permeability was potentiated by luminal perfusion with lidocaine and diminished by vasoactive intestinal peptide (VIP) but unaltered by elevated intraluminal pressure. Elevation of intraluminal pressure, however, potentiated the stimulatory effect of NKA on bicarbonate secretion. In contrast, the tachykinin decreased the rate of alkalinization in rats subjected to elevated intraluminal pressure and treated with indomethacin. Similarly, NKA partially inhibited the VIP-stimulated bicarbonate secretion. Luminal lidocaine did not affect the secretory response to NKA. The motility induced by NKA was unaffected by VIP or lidocaine but decreased by elevated intraluminal pressure. It is concluded that the NKA-induced increase in duodenal mucosal bicarbonate secretion is independent of neurons and possibly mediated by prostanoids. The increase in mucosal permeability in response to NKA may be suppressed by mucosal nerves, perhaps utilizing VIP as one of the transmitters.

Absorçäo de líquido de irrigaçäo na ressecçäo transuretral da próstata em cäes / Irrigating fluid absorption during transurethral resection of the prostate in dogs

Trinta e dois cäes submetidos a entubaçäo do ducto torácico e cateterismo bilateral dos ureteres, foram divididos em 3 grupos: A- 4 cäes inoculados com RISA 131 I ou EDTA 51 Cr por via intravenosa ou peri-prostática; B- controle de 8 cäes submetidos a irrigaçäo vesical e prostática com 8 litros de glicina a 1,2 por cento contendo os marcadores radioativos; C- 8 cäes manejados como em B mas sujeitos à RTU da próstata. Os cäes foram acompanhados por 5 horas. A absorçäo de líquido de irrigaçäo foi calculada pelos métodos volumétrico e radioisotópico. Em 5 horas, 97 por cento da RISA 131 I inoculada via intravenosa permanecia neste espaço enquanto apenas 4,6 por cento da injetada no espaço peri-prostático penetrou no compartimento vascular. Para o EDTA 51 Cr, 63,6 por cento da massa inoculada no espaço peri-prostático foi recuperada na urina após 5 horas. O método volumétrico mostrou absorçäo média de 22,7 ml no grupo B e 276 ml no C, e o radioisotópico de 6,3 ml e 165,4 ml, respectivamente. O modelo experimental tem similaridades com o ser humano

Biokinetics and dosimetry of chromium, cobalt, hydrogen, iron and zinc radionuclides in male reproductive tissues of the rat.

Following intravenous administration to male rats, the uptake and retention by reproductive tissues of chromium-51, cobalt-57, iron-59, zinc-65 and tritium has been studied for up to 28 days. Chromium-51, 57Co, 59Fe and 3H were not or only transiently accumulated in gonads or accessory sex glands at concentrations greater than whole body concentrations. However, 65Zn was concentrated in the dorsolateral region of the prostate gland and autoradiography showed preferential uptake by epithelial cells and lumen of glands. When combined with other information available from the literature, this data would suggest that current models adequately describe the biokinetics of chromium, cobalt, iron and tritium in the prostate and testes and zinc in the testes. Uptake of zinc by the prostate would appear to be best described by an average value of 0.1% and a conservative value of 0.5%. Allowing for greater uptake of zinc (0.5%) by the prostate, after inhalation of 65Zn in a soluble form increases prostate dose by about 3 fold compared to current models. The pessimistic assumptions of a higher relative biological effectiveness (20) for all Auger emissions from 65Zn in cell nuclei and a heterogeneous distribution of 65Zn to sensitive cells in the prostate increases prostate dose by a further factor of 9. Even on the basis of these cautions estimates, occupational exposures to radioisotopes of these elements do not explain the excess of prostate cancer reported amongst some nuclear workers.

Long-term follow-up of kidney donors: a longitudinal study.

BACKGROUND: Kidney donors are not adversely affected by compensatory hyperfiltration of the remaining kidney in the early years after nephrectomy, but longterm longitudinal studies are lacking. METHODS: The renal function and blood pressure of 75 donors was evaluated in 1984, 1.4-20.7 years after surgery. Forty-seven of the original cohort (23 male, age 38-80 years) underwent repeat study a decade later (12-31 years post-nephrectomy), using identical laboratory techniques. RESULTS: Glomerular filtration rates (GFR) as measured by 51Cr EDTA clearance was relatively unchanged a decade later with 41 of 47 subjects (87%) having EDTA clearance within the normal laboratory reference range at review. The change in GFR in the remaining six subjects was statistically not significant. No correlation between GFR and time after nephrectomy was detected. Albumin excretion rate (AER), on timed overnight urine collections, was increased (> 20 micrograms/min) in 16 subjects (34%), although 14 of these individuals were also hypertensive. The prevalence of hypertension was significantly increased compared with age/sex matched data from epidemiological studies of the general population (both in the UK and the US), especially in those over the age of 55 years. CONCLUSION: This study demonstrates that the function of the solitary kidney is not adversely affected by prolonged compensatory hyperfiltration, although there appears to be an increased prevalence of microalbuminuria and hypertension. Regular follow-up of kidney donors is recommended in order to manage their complications effectively and to detect hypertension and or renal impairment early in those who may develop it.

[Double isotope albumin flux measurement: diagnosis and therapeutic monitoring of acute lung injury]. / Doppelisotopen-Albuminfluxmessung: Diagnose und Therapiemonitoring des Acute Lung Injury.

PURPOSE: Acute Lung Injury (ALI) is a clinical condition which is associated with a high lethality. It is characterized by an increased pulmonary capillary permeability and non-cardiogenic pulmonary edema. This study was designed to answer the question whether double isotope albumin-flux measurement is a useful tool both for diagnosis of increased pulmonary capillary permeability and for monitoring therapeutic interventions (nitric oxide (NO) inhalation). METHOD: In 12 patients with clinical signs of ALI, transvascular albumin-flux was measured by a double radioisotope technique before, during and after NO inhalation. 99mTc labeled albumin and 51Cr labeled autologous erythrocytes were used as tracer. The radioactivity of both radiopharmaceuticals was measured externally over the right lung by a radiation probe and simultaneously in arterial blood. For quantification of transvascular albumin-flux Normalized Index (NI) and Normalized Slope Index (NSI) were calculated. Furthermore, pulmonal vascular pressures and other physiological parameters were recorded. RESULTS: All 12 patients showed markedly increased NSI before inhalation of NO. NSI decreased from 0.0074 +/- 0.0046 min-1 without nitric oxide to -0.0051 +/- 0.0041 min-1 during nitric oxide and increased to 0.0046 +/- 0.0111 min-1 after nitric oxide. The decrease of the NSI correlated well with decrease of venous pulmonary resistance during inhalation of NO. CONCLUSION: Inhalation of NO reduces transvascular albumin-flux in patients with ALI. Double isotope albumin-flux measurement enables diagnosis of increased capillary permeability as well as monitoring therapeutic interventions.

Analysis of tumor-infiltrating lymphocytes in cutaneous squamous cell carcinoma.

OBJECTIVE: To characterize tumor-infiltrating lymphocytes (TILs) within lesions of cutaneous squamous cell carcinoma (SCC) and related disorders. DESIGN: Case series with 1- and 2-color immunohistologic, molecular biological analysis of T-cell clonality and in vitro cytotoxicity assays. SETTING: Academic medical center. PATIENTS: Twenty-one patients, including 6 with actinic keratoses, 4 with SCC in situ, and 11 with invasive SCC. RESULTS: CD8+ TILs were present within lesions of cutaneous SCC and AK. These cells constituted a variable minority of the total T-cell infiltrate, and many expressed a phenotype consistent with major histocompatibility complex-restricted cytotoxic T lymphocytes: CD3+, TIA1+, CD16-, CD56-, CD57-. They also expressed HLA-DR, suggesting their activation in vivo. Virtually all T cells were T-cell receptor (TCR)-beta + delta, indicating that they expressed the TCR-alpha beta protein heterodimer. Molecular biological analysis of TCR-gamma gene rearrangements by the polymerase chain reaction and denaturing gradient gel electrophoresis technique indicated that the TILs were polyclonal. Functional studies suggested that TILs derived from SCC lesions were cytotoxic for autologous tumor cell targets. CONCLUSION: Tumor-infiltrating lymphocytes within cutaneous SCC lesions contain a subpopulation of polyclonal, major histocompatibility complex-restricted cytotoxic T lymphocytes expressing the TCR-alpha beta heterodimer.