Association of human liver bilirubin UDP-glucuronyltransferase activity with a polymorphism in the promoter region of the UGT1A1 gene

BACKGROUND/AIMS: Gilbert's syndrome is a benign form of a deficiency in bilirubin glucuronidation. It is associated with a homozygous polymorphism, A(TA)7TAA instead of A(TA)6TAA, in the TATA-box of the promoter region of the bilirubin UDP-glucuronyltransferase gene. In this study the correlation between this promoter region polymorphism and in vitro human liver bilirubin UDP-glucuronyltransferase enzyme activity was investigated. METHODS: Liver samples from organ transplant donors n=39) and two known Gilbert's syndrome patients were used for measuring bilirubin UDP-glucuronyltransferase enzyme activity and for isolation of DNA followed by detection of the promoter region polymorphism by polymerase chain reaction. Genotypes were assigned as follows; 6/6: homozygous for the A(TA)6TAA-allele, 7/7: homozygous for the A(TA)7TAA-allele, and 6/7: heterozygous with one of each alleles. RESULTS: Seventeen out of 39 subjects (44%) had the homozygous 6/6 genotype, 18 subjects (46%) had the heterozygous 6/7 genotype, whereas four individuals (10%) and the two individuals with Gilbert's syndrome had the 7/7 genotype correlated with Gilbert's syndrome. This resulted in an allele frequency of 0.33 for the A(TA)7TAA-allele. The median bilirubin UDP-glucuronyltransferase enzyme activity of the 17 subjects with the 6/6 genotype (1565 nmol/g liver/h) was significantly higher than the activity of the 18 subjects with the 6/7 genotype (985 nmol/g liver/h; p<0.05) and the six individuals with the 7/7 genotype (749 nmol/g liver/h; p<0.005). No significant differences in enzyme activity were found between the 6/7 and the 7/7 genotype groups. CONCLUSIONS: The results indicate a close association between the promoter region genotype and the expression of hepatic bilirubin UDP-glucuronyltransferase enzyme activity. Subjects who have a 7/7 genotype have the lowest enzyme activity, whereas subjects with the heterozygous 6/7 genotype have an intermediate enzyme activity.     

Hypoproteinemia as a marker of acute respiratory distress syndrome in critically ill patients with pulmonary edema

OBJECTIVE: To assess the value of serum protein levels for differentiating permeability pulmonary edema in the course of acute respiratory distress syndrome (ARDS) from cardiogenic pulmonary edema (CPE). DESIGN AND SETTING: Observational cohort study in intensive care units of 720-bed university hospital. PATIENTS: Twenty-four consecutive patients with clinical evidence of edema, 11 fulfilling the consensus definition of ARDS, 7 having sepsis, 5 with all ARDS consensus criteria and sepsis but a pulmonary capillary wedge pressure above 18 mmHg (mixed), and 8 with CPE. All patients except for one with CPE were mechanically ventilated. MEASUREMENTS AND RESULTS: Radionuclide assessments of pulmonary microvascular protein (transferrin) permeability (pulmonary leak index, PLI) were carried out and serum protein levels determined at admission and for ARDS/mixed patients, at recovery, defined by a decrease in positive end-expiratory pressure to 0 cmH2O. At admission the PLI was higher in ARDS/mixed than in CPE patients. The total protein and transferrin levels were lower in the former. The area under the curve of the receiver operating characteristic for diagnosing ARDS (vs. CPE) was 0.98 for transferrin (cutoff value 1.5 g/l), 0.95 for total protein (cutoff value 59 g/l) and 0.80 for albumin (cutoff value 24 g/l) levels. In various clinical diagnostic groups the transferrin level approached the PLI in diagnostic value. At recovery the PLI had decreased and serum protein levels increased. CONCLUSIONS: The data suggest that hypoproteinemia is a marker of ARDS. This may partially reflect increased permeability in the lungs, systemically, or both.     

Acute lung injury after aortic surgery: the relation between lung and leg microvascular permeability to 111indium-labelled transferrin and circulating mediators

BACKGROUND: Aortic surgery is a risk factor for acute lung injury and this may relate to ischaemia/reperfusion (I/R) of the lower body and release of inflammatory mediators. The aim of this study was to define the changes in microvascular protein permeability and circulating inflammatory mediators after aortic surgery. METHODS: In 11 consecutive patients who underwent elective aortic surgery microvascular permeability in lung and leg was measured before and a median of 2.8 hours after completion of surgery using 111indium (In)-labelled transferrin and 99mtechnetium (Tc)-labelled red blood cells, yielding a protein leak index (PLI) that is specific for protein permeability. Circulating leucocyte counts and levels of inflammatory mediators were determined. RESULTS: In the lung the PLI rose from a median of 0.6 (range -0.5 to 2.2) x 10(-3)/min before surgery to 5.4 (-2.3 to 33.5) x 10(-3)/min after surgery, and in the leg from 0.3 (-1.6 to 1.7) x 10(- 3)/min to 5.0 (1.0 to 27.8) x 10(-3)/min. The increase in PLI in the lung was related to that in the leg. Levels of activated complement C3a and tumour necrosis factor-alpha did not change, but levels of interleukin (IL)-6, IL-8 and elastase-alpha 1-antitrypsin increased. After surgery there was slight neutrophilia and the leucocyte counts were inversely related to the IL-8 level. The rise in lung but not in leg PLI was greatest in patients with the highest IL-8 levels and the lowest leucocyte counts. CONCLUSIONS: Early after aortic surgery microvascular protein permeability increases in the leg and lung. Leg I/R injury may result in neutrophil activation and release of IL-8, which may induce neutrophil sequestration and subsequently increased pulmonary microvascular permeability. These findings may help to explain the occurrence of acute lung injury after I/R in man.


     

Is subendocardial ischaemia present in patients with chest pain and normal coronary angiograms? A cardiovascular MR study

Aims: On the basis of an MRI study it has been suggested that subendocardialhypoperfusion is present in patients with cardiac syndrome X.However, further work is required to test whether these findingscan be generalized. Methods and results: MRI was used to visually and semi-quantitatively assess subendocardialand subepicardial perfusion, at rest and during an infusionof adenosine, in 20 patients with angina pectoris and normalcoronary angiograms. A myocardial perfusion index (MPI) wascalculated using the normalized upslope of myocardial signalenhancement. An index for myocardial perfusion reserve (MPRI)was calculated by dividing the MPI values at maximal vasodilatationby the values at rest. The MPI in our study population increasedsignificantly during adenosine infusion in both the subendocardium(from 0.091 ± 0.020 to 0.143 ± 0.030; P < 0.001)and the subepicardium (from 0.074 ± 0.017 to 0.135 ±0.03; P < 0.001). The overall MPRI was 1.83 ± 0.50. Conclusion: The results show that patients with chest pain and normal coronaryangiograms had significant perfusion responses to adenosinein both the subendocardium and subepicardium. In the presentstudy we found no evidence for subendocardial hypoperfusionin these patients.     

Oxidized and free whole blood thiols in preeclampsia

OBJECTIVE: To measure levels of oxidized and free thiols in whole blood of normotensive pregnant and preeclamptic women and evaluate the role of oxidative stress. METHODS: We measured whole blood oxidized and free levels of cysteine, homocysteine, cysteinylglycine, and glutathione by high performance liquid chromatography in women with normotensive pregnancies (n = 50), preeclampsia (n = 29), and preeclampsia complicated by the hemolysis, elevated liver enzymes, low platelets (HELLP) syndrome (n = 16). RESULTS: Oxidized and free levels (median [range], micromol/L) of cysteine and homocysteine were higher in women with preeclampsia than normotensive pregnancies (45 [27-81] versus 29 [9-91], P <.001, and 98 [57-193] versus 69 [33-215], P <.001; 0.8 [0.2-4.4] versus 0.4 [0.01-1.6], P <.001, and 2.1 [0.7-9.4] versus 1.2 [0.2-21.2], P <.01; respectively). The ratios of free to oxidized cysteine, homocysteine, and cysteinylglycine were lower in preeclampsia than normotensive pregnancy (2.2 [1.3-3.0] versus 2.4 [1.7-4.3], P <.001; 2.3 [0.5-5.4] versus 2.9 [1.1-24], P <.001; 4.1 [2.3-11.6] versus 5.4 [2.6-24.3], P <.02, respectively), indicating a shift in favor of the oxidized form of those thiols. In HELLP syndrome, levels of oxidized and free cysteine and levels of oxidized homocysteine were higher than normal (44 [33-63] versus 29 [9-91], P <.001, and 102 [82-133] versus 69 [33-215], P <.001; 1.0 [0.3-2.9] versus 0.4 [0.01-1.6], P <.001, respectively). No significant differences were found in oxidized glutathione levels in women with preeclampsia (22 [5-49] versus 17 [2- 60], P =.06) or free levels in preeclamptic women with HELLP syndrome (757 [624-993] versus 842 [539-1516], P =.09) as compared with normotensive pregnant women. The ratios of free to oxidized cysteinylglycine and glutathione were higher in women with HELLP syndrome than in those with preeclampsia (5.4 [3.3-12.7] versus 4.1 [2.3-11.6], P =.02, and 56 [28-124] versus 45 [16-166], P =.02, respectively). CONCLUSION: Significantly lower ratios of free to oxidized cysteine, homocysteine, and cysteinylglycine in preeclampsia might indicate oxidative stress.     

Delayed resolution of pulmonary oedema after cocaine/heroin abuse.

Pulmonary oedema lasting six days occurred in a 68 year old man after sniffing cocaine. He also had evidence of parenteral self-administration of heroin. Pulmonary microvascular filtration pressure and permeability were normal. Delayed resolution of the pulmonary oedema may have been caused by a cocaine-induced impairment of sodium and thus fluid transport across alveolar epithelium. Recognition may be important, since lowering filtration pressure with diuretics may not hasten resolution of oedema.     

Donor-to-host transmitted Candida endophthalmitis after penetrating keratoplasty

OBJECTIVE: To report the first case of Candida albicans endophthalmitis following penetrating keratoplasty after warm preservation. DESIGN: Observational case report. METHODS: We reviewed the patient's chart and the available literature on fungal endophthalmitis after keratoplasty. RESULTS: After keratoplasty, a 45-year-old man developed an endophthalmitis on the first postoperative day. The same day, results of the culture of the transportation medium were available and revealed Candida albicans. Despite therapy with topical and subtenon amphotericin B, there was no clinical improvement, and a regraft was performed 4 days after the initial corneal transplant. A best corrected visual acuity of 20/32 was achieved. CONCLUSION: The majority of reported cases of postkeratoplasty candidal endophthalmitis are associated with cold storage preservation and a poor prognosis of the affected eye. We describe a case of postkeratoplasty candidal endophthalmitis after organ-cultured preservation, with a final visual acuity above expectations. In our opinion, early diagnosis based on routine culturing of the transportation medium and early removal of the infected corneal graft when local antifungal therapy failed are important factors contributing to the good clinical outcome.     

A comparison of radiographic and scintigraphic techniques to assess aseptic loosening of the acetabular component in a total hip replacement

BACKGROUND: The diagnosis of a loose total hip prosthesis is often established with use of radiographic and nuclear medicine techniques, but there is controversy about the relative utility of plain radiography, subtraction arthrography, nuclear arthrography, and bone scintigraphy. In this retrospective study, we evaluated the sensitivity, specificity, and interobserver reliability of these imaging modalities in patients suspected of having aseptic loosening of the acetabular component. METHODS: From 1994 to 1999, eighty-six consecutive patients with pain after a total hip arthroplasty were evaluated for possible loosening of the components. The imaging evaluation included plain radiography followed by a one-day protocol that included bone scintigraphy, subtraction arthrography, and nuclear arthrography. For this study, two experienced nuclear medicine physicians and two experienced radiologists, all of whom were blinded with respect to the clinical pretest data and the clinical outcome, retrospectively interpreted the diagnostic images. The sensitivity and the specificity of each imaging modality were established by comparing the findings obtained with each technique with those found at surgery or during the subsequent clinical course of the patient. Interobserver variability was determined with the intraclass correlation coefficient. RESULTS: Plain radiography had a sensitivity of 85% (95% confidence interval, 71 to 94) and a specificity of 85% (95% confidence interval, 66 to 96) in detecting aseptic loosening of the acetabular component, but it had only fair interobserver variability (intraclass correlation coefficient, 0.37). For subtraction arthrography, the sensitivity was 72% (95% confidence interval, 57 to 84), the specificity was 70% (95% confidence interval, 50 to 86), and there was good interobserver variability (intraclass correlation coefficient, 0.71). For nuclear arthrography, the sensitivity was 57% (95% confidence interval, 41 to 71), the specificity was 67% (95% confidence interval, 46 to 84), and there was fair interobserver variability (intraclass correlation coefficient, 0.24). For bone scintigraphy, the sensitivity was 83% (95% confidence interval, 69 to 92), the specificity was 67% (95% confidence interval, 46 to 84), and there was moderate interobserver variability (intraclass correlation coefficient, 0.43). CONCLUSIONS: Plain radiography had the highest diagnostic accuracy in the evaluation of aseptic loosening of the acetabular component. The diagnostic accuracy was increased when plain radiography was combined with bone scintigraphy or subtraction arthrography. However, we found considerable interobserver variability in image interpretation, even with experienced radiologists and nuclear medicine physicians.