Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 84
Filter
1.
PLoS One ; 16(2): e0246394, 2021.
Article in English | MEDLINE | ID: mdl-33529259

ABSTRACT

INTRODUCTION: Dynamic PET/CT allows visualization of pharmacokinetics over the time, in contrast to static whole body PET/CT. The objective of this study was to assess 68Ga-PSMA-11 uptake in pathological lesions and benign tissue, within 30 minutes after injection in primary prostate cancer (PCa) patients in test-retest setting. MATERIALS AND METHODS: Five patients, with biopsy proven PCa, were scanned dynamically in list mode for 30 minutes on a digital PET/CT-scanner directly after an intravenous bolus injection of 100 MBq 68Ga-PSMA-11. Approximately 45 minutes after injection a static whole body scan was acquired, followed by a one bed position scan of the pelvic region. The scans were repeated approximately four weeks later, without any intervention in between. Semi-quantitative assessment was performed using regions-of-interest in the prostate tumor, bladder, gluteal muscle and iliac artery. Time-activity curves were extracted from the counts in these regions and the intra-patient variability between both scans was assessed. RESULTS: The uptake of the iliac artery and gluteal muscle reached a plateau after 5 and 3 minutes, respectively. The population fell apart in two groups with respect to tumor uptake: in some patients the tumor uptake reached a plateau after 5 minutes, whereas in other patients the uptake kept increasing, which correlated with larger tumor volumes on PET/CT scan. Median intra-patient variation between both scans was 12.2% for artery, 9.7% for tumor, 32.7% for the bladder and 14.1% for the gluteal muscle. CONCLUSION: Dynamic 68Ga-PSMA-11 PET/CT scans, with a time interval of four weeks, are reproducible with a 10% variation in uptake in the primary prostate tumor. An uptake plateau was reached for the iliac artery and gluteal muscle within 5 minutes post-injection. A larger tumor volume seems to be related to continued tumor uptake. This information might be relevant for both response monitoring and PSMA-based radionuclide therapies.


Subject(s)
Gallium Isotopes/analysis , Gallium Radioisotopes/analysis , Prostate/diagnostic imaging , Prostatic Neoplasms/diagnostic imaging , Aged , Gallium Isotopes/administration & dosage , Gallium Isotopes/pharmacokinetics , Gallium Radioisotopes/administration & dosage , Gallium Radioisotopes/pharmacokinetics , Humans , Male , Pelvis/pathology , Positron Emission Tomography Computed Tomography , Prostate/pathology , Prostatic Neoplasms/pathology , Tumor Burden
2.
Hum Antibodies ; 20(1-2): 7-14, 2011.
Article in English | MEDLINE | ID: mdl-21558619

ABSTRACT

Rheumatoid arthritis is a destructive inflammatory joint disorder. Pre- and mature B-cells, characterized by CD20 antigen expression, play an important role in the inflammatory process. Rituximab, a chimeric monoclonal antibody against the CD20 antigen, has been approved since 2006 for the treatment of patients with rheumatoid arthritis. However, not all patients benefit from this treatment. Persistent activity of the disease has been reported despite treatment with rituximab. Imaging of radiolabeled rituximab can be used to monitor the biodistribution of rituximab, and potentially to predict the efficacy of the treatment. In this study, rituximab was radiolabeled with ¹²4Iodine for positron emission tomography (PET) imaging. The aim of this study was to investigate the pharmacokinetics and biodistribution of ¹²4I-rituximab in patients with rheumatoid arthritis, to establish the optimal procedure for PET imaging. Eligible patients received 50 MBq ¹²4I-rituximab, corresponding to approximately 1.5 mg rituximab. Wholebody PET/CT imaging was performed at 10 min, 24 hrs, and 48 hrs post injection. The total body activity, radioactivity in whole blood, and rituximab serum levels were determined. ¹²4I-rituximab has favorable pharmacokinetics for targeting of (pathological) B cells and imaging over several days, but only after pre-treatment with unlabeled rituximab. In addition, protection of the thyroid is recommended to prevent uptake of released ¹²4I.


Subject(s)
Antibodies, Monoclonal, Murine-Derived/pharmacokinetics , Antibodies, Monoclonal/pharmacokinetics , Antirheumatic Agents/pharmacokinetics , Arthritis, Rheumatoid/drug therapy , Positron-Emission Tomography/methods , Antibodies, Monoclonal/immunology , Antibodies, Monoclonal, Murine-Derived/immunology , Antigens, CD20/biosynthesis , Antigens, CD20/immunology , Antirheumatic Agents/immunology , Arthritis, Rheumatoid/diagnosis , Arthritis, Rheumatoid/immunology , Arthritis, Rheumatoid/pathology , B-Lymphocytes/immunology , B-Lymphocytes/metabolism , B-Lymphocytes/pathology , Drug Administration Schedule , Humans , Iodine Radioisotopes/adverse effects , Isotope Labeling/methods , Rituximab , Thyroid Gland/drug effects , Tissue Distribution , Treatment Outcome , Whole Body Imaging
3.
Med Biol Eng Comput ; 47(7): 773-82, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19468771

ABSTRACT

UNLABELLED: This study assesses intra- and inter-patient variability in endotracheal climate (temperature and humidity) and effects of heat and moister exchangers (HME) in 16 laryngectomized individuals, measured repeatedly (N = 47). Inhalation Breath Length (IBL) was 1.35 s without HME and 1.05 s with HME (P < 0.0001). With HME, end-inspiratory (minimum) humidity values increased 5.8 mg H(2)O/L (P < 0.0001) and minimum temperature values decreased 1.6 degrees C (P < 0.0001). For the temperature and humidity minimums, the inter-patient variability was much smaller than the short- and long-term intra-patient variability. For exhalation breath length and full breath length, the opposite was the case. CONCLUSIONS: (1) Because inter-patient variability is smaller than intra-patient variability, investigating endotracheal climate in a limited number of laryngectomized subjects is justified, provided repeated measurements per patient are accomplished; (2) main contributor to intra-patient variability is the positioning of the catheter tip in the trachea; (3) an HME leads to a shortened IBL which enhances the HME effect.


Subject(s)
Laryngectomy , Trachea/physiopathology , Aged , Aged, 80 and over , Female , Heating/methods , Humans , Humidity , Male , Middle Aged , Reproducibility of Results , Respiratory Mechanics/physiology , Temperature
4.
Med Biol Eng Comput ; 45(8): 737-45, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17629761

ABSTRACT

The aim of this study is to develop a postlaryngectomy airway climate explorer (ACE) for assessment of intratracheal temperature and humidity and of influence of heat and moisture exchangers (HMEs). Engineering goals were within-device condensation prevention and fast response time characteristics. The ACE consists of a small diameter, heated air-sampling catheter connected to a heated sensor house, containing a humidity sensor. Air is sucked through the catheter by a controlled-flow pump. Validation was performed in a climate chamber using a calibrated reference sensor and in a two-flow system. Additionally, the analyser was tested in vivo. Over the clinically relevant range of humidity values (5-42 mg H2O/l air) the sensor output highly correlates with the reference sensor readings (R2 > 0.99). The 1-1/e response times are all <0.5 s. A first in vivo pilot measurement was successful. The newly developed, verified, fast-responding ACE is suitable for postlaryngectomy airway climate assessment.


Subject(s)
Body Temperature , Laryngectomy , Postoperative Care/instrumentation , Trachea/physiopathology , Calibration , Equipment Design , Hot Temperature , Humans , Humidity , Monitoring, Physiologic/instrumentation , Pilot Projects
5.
Acta Anaesthesiol Scand ; 51(6): 693-700, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17567269

ABSTRACT

BACKGROUND: Dysfunction of the microcirculation is a prominent feature of sepsis and endotoxemia. Recently, it has been shown that microcirculatory alterations are completely reversed by local or systemic application of vasodilators in severely septic patients. Therefore, we investigated the influence of vasodilator therapy on microcirculatory dysfunction of the ileum during endotoxic shock in a prospective, controlled animal study. METHODS: After baseline measurements, shock was induced in 12 domestic pigs by lipopolysaccharide via the mesenteric vein until the mean arterial pressure fell below 60 mmHg. After 30 min in shock, six animals were resuscitated with either fluid alone (control) or fluid and 2 microg/kg/min of the vasodilator 3-morpholino-sydnonimine (SIN-1). The systemic and regional hemodynamics and oxygenation parameters, tonometric ileal P(CO(2)) and microvascular oxygen pressures (muP(O(2))) (by oxygen-dependent Pd-porphyrin phosphorescence) were measured simultaneously. RESULTS: The ileal-arterial P(CO(2)) gap increased during shock and the ileal mucosal and serosal muP(O(2)) decreased concurrently. SIN-1 in addition to fluid resuscitation significantly improved the ileal-arterial P(CO(2)), whereas fluid alone failed to decrease the P(CO(2)) gap. The SIN-1-induced improvement in the P(CO(2)) gap was accompanied by an increase in serosal muP(O(2)) above shock levels. Mucosal muP(O(2)) was resuscitated to baseline levels in both groups. CONCLUSION: The application of the vasodilator SIN-1 in addition to fluid resuscitation improves the ileal-arterial P(CO(2)) gap and mucosal muP(O(2)), together with a moderate increase in serosal muP(O(2)), after endotoxic shock. This finding is consistent with the concept that vasodilators may correct pathologic flow distribution within the intestinal wall.


Subject(s)
Arteries/physiology , Carbon Dioxide/blood , Endotoxemia/blood , Intestines/blood supply , Molsidomine/analogs & derivatives , Nitric Oxide Donors/pharmacology , Animals , Blood Pressure , Disease Models, Animal , Male , Microcirculation , Molsidomine/pharmacology , Oxygen/blood , Partial Pressure , Regional Blood Flow , Swine , Vasodilator Agents/pharmacology
6.
Thorax ; 61(7): 627-35, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16384879

ABSTRACT

There is great heterogeneity in the clinical manifestations of cystic fibrosis (CF). Some patients may have all the classical manifestations of CF from infancy and have a relatively poor prognosis, while others have much milder or even atypical disease manifestations and still carry mutations on each of the CFTR genes. It is important to distinguish between these categories of patients. The European Diagnostic Working Group proposes the following terminology. Patients are diagnosed with classic or typical CF if they have one or more phenotypic characteristics and a sweat chloride concentration of >60 mmol/l. The vast majority of CF patients fall into this category. Usually one established mutation causing CF can be identified on each CFTR gene. Patients with classic CF can have exocrine pancreatic insufficiency or pancreatic sufficiency. The disease can have a severe course with rapid progression of symptoms or a milder course with very little deterioration over time. Patients with non-classic or atypical CF have a CF phenotype in at least one organ system and a normal (<30 mmol/l) or borderline (30-60 mmol/l) sweat chloride level. In these patients confirmation of the diagnosis of CF requires detection of one disease causing mutation on each CFTR gene or direct quantification of CFTR dysfunction by nasal potential difference measurement. Non-classic CF includes patients with multiorgan or single organ involvement. Most of these patients have exocrine pancreatic sufficiency and milder lung disease. Algorithms for a structured diagnostic process are proposed.


Subject(s)
Algorithms , Cystic Fibrosis/diagnosis , Terminology as Topic , Action Potentials , Chlorides/analysis , Cystic Fibrosis/genetics , Cystic Fibrosis Transmembrane Conductance Regulator/analysis , Cystic Fibrosis Transmembrane Conductance Regulator/genetics , Humans , Infant, Newborn , Ion Transport , Mutation/genetics , Neonatal Screening , Pedigree , Sweat/chemistry
7.
J Cyst Fibros ; 1(2): 51-75, 2002 Jun.
Article in English | MEDLINE | ID: mdl-15463811

ABSTRACT

This document is the result of an European Consensus conference which took place in Artimino, Tuscany, Italy, in March 2001 involving 33 experts on nutrition in patients with cystic fibrosis, organised by the European Cystic Fibrosis Society, and sponsored by Axcan-Scandipharm, Baxter, Dr Falk Pharma, Fresenius, Nutricia, SHS International, Solvay Pharmaceuticals (major sponsor). The purpose of the conference was to develop a consensus document on nutrition in patients with cystic fibrosis based on current evidence.


Subject(s)
Child Development/physiology , Cystic Fibrosis/complications , Growth/physiology , Malnutrition/therapy , Nutritional Support/methods , Adolescent/physiology , Adult , Anthropometry , Child , Deficiency Diseases/etiology , Deficiency Diseases/physiopathology , Deficiency Diseases/therapy , Dietary Supplements , Europe , Exocrine Pancreatic Insufficiency/etiology , Exocrine Pancreatic Insufficiency/therapy , Humans , Malnutrition/etiology , Malnutrition/physiopathology , Nutritional Physiological Phenomena/physiology , Nutritional Status/physiology
8.
Hum Mutat ; 18(3): 233-42, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11524734

ABSTRACT

Congenital chloride diarrhea (CLD) is an autosomal recessive disorder characterized by defective intestinal electrolyte absorption, resulting in voluminous osmotic diarrhea with high chloride content. A variety of mutations in the solute carrier family 26, member 3 gene (SLC26A3, previously known as CLD or DRA) are responsible for the disease. Since the identification of the SLC26A3 gene and the determination of its genomic structure, altogether three founder and 17 private mutations have been characterized within miscellaneous ethnic groups. We screened for mutations in seven unrelated families with CLD. The diagnoses were confirmed by fecal chloride measurements. The combined PCR-SSCP and sequencing analyses revealed altogether seven novel mutations including two missense mutations (S206P, D468V), two splicing defects (IVS12-1G>C, IVS13-2delA), one nonsense mutation (Q436X), one insertion/deletion mutation (2104-2105delGGins29-bp), and an intragenic deletion of SLC26A3 exons 7 and 8. Two previously identified mutations were also found. This is the first report of rearrangement mutations in SLC26A3. Molecular features predisposing SLC26A3 for the two rearrangements may include repetitive elements and palindromic-like sequences. The increasingly wide diversity of SLC26A3 mutations suggests that mutations in the SLC26A3 gene may not be rare events.


Subject(s)
Antiporters , Carrier Proteins/genetics , Chlorides/metabolism , Diarrhea/genetics , Gene Deletion , Membrane Proteins/genetics , Base Sequence , Chloride-Bicarbonate Antiporters , Codon, Nonsense , DNA/chemistry , DNA/genetics , DNA Mutational Analysis , Diarrhea/congenital , Family Health , Humans , Mutagenesis, Insertional , Mutation , Mutation, Missense , Polymorphism, Genetic , Polymorphism, Single-Stranded Conformational , Sequence Deletion , Sulfate Transporters
9.
J Pediatr Surg ; 34(8): 1265-8, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10466609

ABSTRACT

BACKGROUND/PURPOSE: Auxiliary liver transplantation is an attractive alternative for orthotopic liver transplantation in patients with certain inborn errors of metabolism of the liver in which complete resection of the liver is unnecessary or even contraindicated. Because in these diseases portal hypertension is mostly absent, finding a balance in portal blood distribution between native liver and graft is complicated. The objective of this study was to investigate requirements for long-term (180 days) graft survival in auxiliary partial heterotopic liver transplantation (APHLT) in a dog model. METHODS: A metabolic defect was corrected in 26 dalmation dogs with a 60% beagle heterotopic auxiliary liver graft. Four groups of different portal inflow were studied. In the ligation group the portal vein to the host liver was ligated. In the split-flow group graft and host liver received separate portal inflow. In the banding group the distribution of the portal flow was regulated with an adjustable strapband and in the free-flow group the portal blood was allowed to flow randomly to host or graft liver. RESULTS: Metabolic correction increased in all groups after transplantation from 0.19 +/- 0.02 to 0.70 +/- 0.05 (P< .0001) but remained significantly better in the ligation and split-flow groups (graft survival, 135 +/- 27 and 144 +/- 31 days). In the banding group metabolic correction decreased significantly after 70 days, and although the grafts kept some function for 155 +/- 14 days, in 4 of 6 dogs portal thrombosis was found. In the free-flow group, competition for the portal blood led to reduced correction within 12 days and total loss of function in 96 +/- 14 days. Graft function also was assessed with technetium (Tc) 99m dimethyl-iminodiacetic acid uptake. A good linear association between HIDA uptake and metabolic correction was observed (r = 0.74; P < .0005). Grafts that contributed more than 15% to the total uptake of HIDA showed biochemical correction. This indicates a critical graft mass of about 15% to 20% of the hepatocyte volume to correct this metabolic defect. CONCLUSION: Auxiliary partial heterotopic liver transplantation can be a valuable alternative treatment for inborn errors of hepatic metabolism if the native liver and the graft receive separate portal blood inflow.


Subject(s)
Graft Survival/physiology , Liver Transplantation/methods , Portal System/physiology , Animals , Dogs , Liver Transplantation/diagnostic imaging , Liver Transplantation/physiology , Metabolism, Inborn Errors/surgery , Portal System/surgery , Radionuclide Imaging , Radiopharmaceuticals , Technetium Tc 99m Lidofenin
10.
Crit Care Med ; 27(7): 1369-77, 1999 Jul.
Article in English | MEDLINE | ID: mdl-10446833

ABSTRACT

OBJECTIVE: To review optical spectroscopic techniques for assessment of the determinants of tissue oxygenation and to evaluate the notion that the disturbances in oxygen pathways in sepsis can be accounted for by enhanced functional shunting of parts of the microcirculation. DATA RESOURCES: Experimental data from previous research and the literature were analyzed. STUDY SELECTION: The data selected pertained to a) whether cellular distress in sepsis is caused by tissue hypoxia or disturbed metabolic pathways, b) optical spectroscopic techniques used to study microcirculatory oxygenation, and c) possible mechanisms underlying shunting of the microcirculation in hypoxemia and sepsis. STUDY SYNTHESIS: Despite resuscitation of oxygen-derived variables, signs of regional tissue hypoxia persist in sepsis. The mechanisms underlying this condition are expected to be associated with oxygen pathways in the microcirculation. Optical spectroscopic techniques are providing new insights into these mechanisms. These include absorption spectroscopy for hemoglobin saturation of erythrocytes, reduced nicotinamide adenine dinucleotide fluorescence for tissue mitochondrial bioenergetics, and palladium-porphyrin phosphorescence for microvascular PO2. Reduced nicotinamide adenine dinucleotide videofluorescence studies have shown the heterogeneous nature of hypoxia. Measurement of gut microvascular PO2 in pigs has shown the development of a PO2 gap between microvascular PO2 and venous PO2 during hemorrhage and endotoxemia, with a larger gap occurring in sepsis than in hemorrhage. It is hypothesized that this difference is caused by the enhanced shunting of the microcirculation present in sepsis. CONCLUSIONS: Microcirculatory distress may form one of the earliest stages in the progress of sepsis to multiple organ failure, and shunting of the microcirculation may be an important contributing factor to this development. To evaluate the severity of microcirculatory distress and the effectiveness of resuscitation strategies, new clinical technologies aimed at the microcirculation will need to be developed. It is anticipated that optical spectroscopy will play a major role in the development of such tools.


Subject(s)
Microcirculation/physiopathology , Oxygen/metabolism , Sepsis/physiopathology , Shock/physiopathology , Spectrum Analysis/methods , Humans , Hypoxia/physiopathology
11.
Am J Physiol ; 276(6): G1515-20, 1999 06.
Article in English | MEDLINE | ID: mdl-10362656

ABSTRACT

Microvascular partial oxygen pressure (PO2) data measured with the quenched phosphorescence of palladium-porphyrin (Pd-porphyrin) with the use of optical fibers have provided new insight into the behavior of the microvascular oxygenation in models of shock. However, the actual microcirculatory compartment measured by this fiber technique has not yet been demonstrated. The purpose of this study was to investigate whether the PO2 of the intestines, as measured using a fiber phosphorometer, reflects the microvascular compartment. To this end, a new intravital phosphorometer with an improved sensitivity to high-PO2 levels (up to 180 mmHg) was developed and validated. With this setup, PO2 values were measured at different inspired oxygen fractions (15, 25, and 50% oxygen) in first-order arterioles, capillaries, and venules of the ileum of rats. Simultaneously, the PO2 was measured with an optical fiber attached to another phosphorometer. PO2 measurements with the fiber phosphorometer show excellent correlation with the PO2 in the capillaries and first-order venule vessels (r2 = 0.94, slope 0.99). We therefore conclude that values measured with the fiber phosphorometer correlate with the capillary and venular PO2.


Subject(s)
Intestines/blood supply , Oxygen/blood , Animals , Luminescent Measurements , Male , Mesoporphyrins , Metalloporphyrins , Microcirculation/physiology , Partial Pressure , Rats , Rats, Wistar
12.
J Physiol ; 514 ( Pt 1): 245-53, 1999 Jan 01.
Article in English | MEDLINE | ID: mdl-9831730

ABSTRACT

1. The aim of this study was to investigate the relation between microvascular and venous oxygen pressures during haemorrhagic shock and resuscitation in the pig intestine. To this end microvascular PO2 (microPO2) was measured by quenching of Pd-porphyrin phosphorescence by oxygen and validated for the intestines. In addition, mesenteric venous blood gasses, blood flow, ilial CO2 production and global haemodynamics were also measured. 2. In one group (n = 11), moderate shock was induced by withdrawal of 40% of the circulating blood volume. Seven of these animals were resuscitated with a crystalloid solution and four with the withdrawn blood. In a second group of three animals, a more severe shock was induced by withdrawal of 50% of the circulating blood volume; these animals were not resuscitated. 3. Baseline mesenteric venous PO2 and microPO2 values were similar (60 +/- 9 and 60 +/- 11 mmHg, respectively). During moderate shock, microPO2 dropped significantly below mesenteric venous PO2 (26 +/- 10 versus 35 +/- 8 mmHg). After resuscitation with crystalloid solution, microPO2 and mesenteric venous PO2 rose to 44 +/- 9 and 44 +/- 6 mmHg, respectively. In the group that received the withdrawn blood, values were 41 +/- 9 and 53 +/- 12 mmHg, respectively. Severe shock resulted in a drop in the mesenteric venous PO2 (n = 3) to a value similar to that seen in the moderate shock group, but the gut microPO2 dropped to a much lower value than that of the moderate shock group (15 +/- 5 versus 26 +/- 10 mmHg). 4. The results indicate that the oxygenation of the microcirculation of the gut can become lower than the venous PO2 under conditions of haemorrhagic shock.


Subject(s)
Ileum/blood supply , Ileum/metabolism , Oxygen/blood , Shock, Hemorrhagic/physiopathology , Animals , Cardiopulmonary Resuscitation , Female , Luminescent Measurements , Mesenteric Veins/physiology , Mesoporphyrins , Metalloporphyrins , Microcirculation/physiology , Palladium , Regional Blood Flow/physiology , Swine
13.
J Lab Clin Med ; 132(5): 421-31, 1998 Nov.
Article in English | MEDLINE | ID: mdl-9823936

ABSTRACT

Using palladium-porphyrin quenching of phosphorescence, we investigated the influence of diaspirin cross-linked hemoglobin (DCLHb) on gut microvascular oxygen pressure (microPO2) in anesthetized pigs. Values of gut microPO2 were studied in correlation with regional intestinal as well as global metabolic and circulatory parameters. A controlled hemorrhagic shock (blood withdrawal of 40 mL/kg) was followed by resuscitation with either a combination of lactated Ringer's solution (75 mL/kg) and modified gelatin (15 mL/kg)(lactR/Gel) or 10% DCLHb (5 mL/kg). After resuscitation, gut microPO2 was similarly improved in the lactR/Gel group (from 25 +/- 10 mm Hg to 53 +/- 8 mm Hg) and the DCLHb group (from 23 +/- 9 mm Hg to 46 +/- 6 mm Hg), which was associated with increased gut oxygen delivery. However, the improvement after resuscitation with DCLHb was sustained for longer periods of time (75 vs 30 min). Mesenteric venous PO2 was increased after resuscitation with lactated Ringer's solution and modified gelatin but not with DCLHb, which was associated with an increased gut oxygen consumption in the latter group. We conclude that measurement of microPO2 by the palladium-porphyrin phosphorescence technique revealed DCLHb to be an effective carrier of oxygen to the microcirculation of the gut. Also, this effect can be achieved with a lower volume than is currently used in resuscitation procedures.


Subject(s)
Aspirin/analogs & derivatives , Blood Substitutes/therapeutic use , Hemoglobins/therapeutic use , Ileum/blood supply , Oxygen Consumption/physiology , Oxygen/blood , Shock, Hemorrhagic/therapy , Animals , Aspirin/therapeutic use , Disease Models, Animal , Female , Hemodynamics/drug effects , Ileum/drug effects , Microcirculation , Partial Pressure , Resuscitation/methods , Shock, Hemorrhagic/blood , Swine
14.
Am J Hum Genet ; 62(3): 585-92, 1998 Mar.
Article in English | MEDLINE | ID: mdl-9497253

ABSTRACT

Crigler-Najjar syndrome type 1 (CN-1) is a recessively inherited, potentially lethal disorder characterized by severe unconjugated hyperbilirubinemia resulting from deficiency of the hepatic enzyme bilirubin-UDP-glucuronosyltransferase. In all CN-1 patients studied, structural mutations in one of the five exons of the gene (UGT1A1) encoding the uridinediphosphoglucuronate glucuronosyltransferase (UGT) isoform bilirubin-UGT1 were implicated in the absence or inactivation of the enzyme. We report two patients in whom CN-1 is caused, instead, by mutations in the noncoding intronic region of the UGT1A1 gene. One patient (A) was homozygous for a G-->C mutation at the splice-donor site in the intron, between exon 1 and exon 2. The other patient (B) was heterozygous for an A-->G shift at the splice-acceptor site in intron 3, and in the second allele a premature translation-termination codon in exon 1 was identified. Bilirubin-UGT1 mRNA is difficult to obtain, since it is expressed in the liver only. To determine the effects of these splice-junction mutations, we amplified genomic DNA of the relevant splice junctions. The amplicons were expressed in COS-7 cells, and the expressed mRNAs were analyzed. In both cases, splice-site mutations led to the use of cryptic splice sites, with consequent deletions in the processed mRNA. This is the first report of intronic mutations causing CN-1 and of the determination of the consequences of these mutations on mRNA structure, by ex vivo expression.


Subject(s)
Crigler-Najjar Syndrome/genetics , Glucuronosyltransferase/genetics , Mutation , RNA Splicing/genetics , Adult , Humans , Infant , Introns , Liver/enzymology , Male , RNA Processing, Post-Transcriptional , RNA, Messenger/genetics , RNA, Messenger/metabolism , RNA, Small Nuclear/genetics
16.
Hum Genet ; 100(3-4): 382-7, 1997 Sep.
Article in English | MEDLINE | ID: mdl-9272159

ABSTRACT

Benign recurrent intrahepatic cholestasis (BRIC) is an autosomal recessive liver disease characterized by multiple episodes of cholestasis without progression to chronic liver disease. The gene was previously assigned to chromosome 18q21, using a shared segment analysis in three families from the Netherlands. In the present study we report the linkage analysis of an expanded sample of 14 BRIC families, using 15 microsatellite markers from the 18q21 region. Obligate recombinants in two families place the gene in a 7-cM interval, between markers D18S69 and D18S64. All intervening markers had significant LOD scores in two-point linkage analysis. Moreover, we identified one family in which the BRIC gene seems to be unlinked to the 18q21 region, or that represents incomplete penetrance of the BRIC genotype.


Subject(s)
Cholestasis, Intrahepatic/genetics , Chromosomes, Human, Pair 18 , Genetic Heterogeneity , Chromosome Mapping , Female , Genotype , Humans , Male , Microsatellite Repeats , Pedigree , Recurrence
17.
Pediatr Res ; 42(2): 195-200, 1997 Aug.
Article in English | MEDLINE | ID: mdl-9262222

ABSTRACT

Patients with Crigler-Najjar syndrome and Gunn rats cannot form bilirubin glucuronides owing to a lack of bilirubin UDP-glucuronosyltransferase activity. Because increased serum and tissue bilirubin levels remain constant, an alternative excretory route has to substitute for this deficiency. Gunn rats excrete in bile only 2-13% of the bilirubins eliminated in Wistar rats. In contrast, the biliary excretion rate of urobilinogen in Gunn and Wistar rats is comparable. The sum of bilirubins and urobilinogen excreted in the bile of Gunn rats amounts to 10-30% of pigments excreted in Wistar rats. Despite this low biliary excretion, the intestinal content and fecal excretion of bile pigments in Gunn and Wistar rats were similar. These data support an extrabiliary entrance of unconjugated bilirubin into the intestine. Additional proof for this was found in that the intestinal lumen of Gunn rats still contains a high amount of bilirubins and urobilinogen after 3 d of external biliary drainage. A similar procedure in Wistar rats resulted in the complete disappearance of bile pigments from the intestine. The direct transmural transport of bilirubin from blood to all parts of the intestinal lumen was demonstrated by injecting 14C-bilirubin i.v. into Gunn rats with isolated parts of small and large intestine. In Crigler-Najjar and Gilbert's syndrome patients, the biliary excretion of bile pigments has previously been shown to be strongly reduced. Their stools, however, contained approximately the same amount of bile pigments as in normal subjects. Although only traces of unconjugated bilirubin were detected in the stool of normal persons (4 +/- 3% of total bile pigments), higher amounts were found in patients with Crigler-Najjar disease (20 +/- 12&). These results suggest a direct intestinal permeation of unconjugated bilirubin in severe unconjugated hyperbilirubinemia both in man and rats.


Subject(s)
Bilirubin/metabolism , Crigler-Najjar Syndrome/physiopathology , Gilbert Disease/physiopathology , Hyperbilirubinemia, Hereditary/physiopathology , Intestinal Mucosa/metabolism , Animals , Case-Control Studies , Humans , Male , Rats , Rats, Gunn , Rats, Wistar
18.
Lab Invest ; 77(1): 19-28, 1997 Jul.
Article in English | MEDLINE | ID: mdl-9251675

ABSTRACT

The survival rate of hepatocytes after allogeneic hepatocyte transplatation (HTX) is low, possibly because of formation of intravascular hepatocyte aggregates. The aim of this study was to determine the role of integrins in intravascular aggregation and intraparenchymal survival of transplanted hepatocytes in a fully allogeneic rat model. First, the expression profile of various integrins was determined on both isolated hepatocytes in vitro and on hepatocyte aggregates in recipient livers after intraportal transplantation of allogeneic hepatocytes. Next, the role of these integrins in hepatocyte aggregation was determined in an in vitro attachment assay on liver sections with function-blocking anti-integrin monoclonal antibodies (mAb). The results showed that anti-alpha 1 beta 1 integrin mAb significantly block hepatocyte attachment to vessel walls and liver parenchyma in vitro. Subsequently, the effect of preincubation of hepatocytes with anti-integrin mAb on their intravascular aggregation and on intraparenchymal survival was studied in an allogeneic HTX model. Preincubation with anti-leukocyte function-associated antigen-1 alpha or anti-beta 2 mAb significantly intravascular hepatocyte aggregation, and anti-leukocyte function-associated antigen-1 alpha mAb enhanced intraparenchymal survival. Preincubation with anti-alpha 1 or anti-beta 1 mAb did not inhibit aggregation but significantly improved survival from 2% to up to 45% at Day 2 after transplantation (p < 0.001). In conclusion, our results suggest that the blocking of alpha 1 beta 1 integrin significantly improves survival of allotransplanted hepatocytes.


Subject(s)
Integrin beta1/metabolism , Integrins/antagonists & inhibitors , Liver Transplantation/pathology , Liver/cytology , Animals , Antibodies, Monoclonal/metabolism , Cell Adhesion , Cell Aggregation , Cell Survival , Immunoenzyme Techniques , In Vitro Techniques , Integrin alpha1beta1 , Integrins/immunology , Male , Rats , Rats, Inbred Lew , Transplantation, Homologous
20.
Acta Paediatr ; 86(5): 466-9, 1997 May.
Article in English | MEDLINE | ID: mdl-9183483

ABSTRACT

Malabsorption of fat is an important gastrointestinal cause of malnutrition and growth retardation in childhood. The gold standard for the evaluation of fat malabsorption is the faecal fat balance method. The acid steatocrit method has recently been introduced as a simple method to evaluate faecal fat. The present study was aimed at evaluating the acid steatocrit in clinical practice. Faecal fat excretion and acid steatocrit results were determined in 42 children, half with and half without fat malabsorption. Acid steatocrit results correlated significantly with both faecal fat excretion (p < 0.01) and faecal fat concentration (p < 0.001). Sensitivity and specificity of the acid steatocrit for the diagnosis of malabsorption were 90% and 100%, respectively. We consider the acid steatocrit method useful for the screening and monitoring of patients with steatorrhoea.


Subject(s)
Celiac Disease/diagnosis , Dietary Fats/analysis , Feces/chemistry , Perchlorates , Adolescent , Case-Control Studies , Celiac Disease/etiology , Celiac Disease/metabolism , Child , Child, Preschool , Cystic Fibrosis/complications , Dietary Fats/metabolism , Humans , Hydrogen-Ion Concentration , Infant , Mass Screening , Reproducibility of Results , Sensitivity and Specificity , Titrimetry
SELECTION OF CITATIONS
SEARCH DETAIL
...