Rapidly Progressive Portal Cavernoma Cholangiopathy in a Patient With Infeasible Decompressive Shunt Surgery.

We present a 27-year-old man with a 2-year history of extrahepatic portal vein obstruction and selective immunoglobulin A deficiency, referred for acute cholangitis from portal cavernoma cholangiopathy (PCC). Because recurrent cholangitis rapidly led to liver failure, orthotopic liver transplantation (OLT) was successfully performed. To date, this is one of the few cases of patients with symptomatic PCC who required OLT and the first case who had a successful 6-year follow-up. Thus, OLT can be used for symptomatic PCC associated with nonshuntable anatomy, ineffective biliary drainage, and progressive liver damage. Selective immunoglobulin A deficiency may play a role in recurrent cholangitis.

Novel curcumin derivatives as P-glycoprotein inhibitors: Molecular modeling, synthesis and sensitization of multidrug resistant cells to doxorubicin.

The MDR1/P-glycoprotein (Pgp)/ABCB1 multidrug transporter is being investigated as a druggable target for antitumor therapy for decades. The natural product curcumin is known to provide an efficient scaffold for compounds capable of blocking Pgp mediated efflux and sensitization of multidrug resistant (MDR) cells to the Pgp transported drug doxorubicin (Dox). We performed molecular dynamics simulations and docking of curcumin derivatives into the Pgp model. Based on these calculations, a series of pyrazolocurcumin derivatives with predicted metabolic stability and/or improved binding affinity were proposed for synthesis and evaluation of MDR reversal potency against Dox selected K562/4 subline, a derivative of K562 human chronic myelogenous leukemia cell line. Compounds 16 and 19 which are both dimethylcurcumin pyrazole derivatives bearing an N-p-phenylcarboxylic amide substitution, were the most potent Pgp blockers as determined by intracellular Dox accumulation. Furthermore, at non-toxic submicromolar concentrations 16 and 19 dramatically sensitized K562/4 cells to Dox. Together with good water solubility of 16 and 19, these results indicate that the new pyrazolo derivatives of curcumin are a promising scaffold for development of clinically applicable Pgp antagonists.

Protective C allele of the single-nucleotide polymorphism rs1335532 is associated with strong binding of Ascl2 transcription factor and elevated CD58 expression in B-cells.

CD58 is expressed on the surface of antigen-presenting cells, including B-cells, and provides co-stimulation to regulatory T-cells (Treg) through CD2 receptor binding. Tregs appear to be essential suppressors of tissue-specific autoimmune responses. Thereby, CD58 plays protective role in multiple sclerosis (MS) and CD58 was identified among several loci associated with MS susceptibility. Minor (C) variant of the single-nucleotide polymorphism (SNP) rs1335532 is associated with lower MS risk according to genome-wide association studies (GWAS) and its presence correlates with higher CD58 mRNA levels in MS patients. We found that genomic region containing rs1335532 has enhancer properties and can significantly boost the CD58 promoter activity in lymphoblast cells. Using bioinformatics and pull-down assay we found that the protective (C) rs1335532 allele created functional binding site for ASCL2 transcription factor, a target of the Wnt signaling pathway. Both in B-lymphoblastoid cell lines and in primary B-cells, as well as in a monocytic cell line, activation of Wnt signaling resulted in an increased CD58 promoter activity in the presence of the protective but not the risk allele of rs1335532, whereas ASCL2 knockdown abrogated this effect. In summary, our results suggest that ASCL2 mediates the protective function of rs1335532 minor (C) allele in MS.

Enhanced liver fibrosis test in patients with psoriasis, psoriatic arthritis and rheumatoid arthritis: a cross-sectional comparison with procollagen-3 N-terminal peptide (P3NP).

BACKGROUND: The enhanced liver fibrosis (ELF) test has been introduced to screen, diagnose and/or monitor liver conditions in large groups of patients with liver diseases. It has not been used in inflammatory skin or joint diseases. OBJECTIVES: To evaluate the distribution of the ELF test, apply existing cut-offs for hepatic patients and healthy controls, and compare it with the procollagen-3 N-terminal peptide (P3NP) test in patients with psoriasis (PSO), psoriatic arthritis (PsA) and rheumatoid arthritis (RA), and controls. METHODS: In total, 531 patients were included. Demographic, lifestyle and disease-specific data were collected. ELF and P3NP tests were performed. RESULTS: Prevalence of an increased ELF score (> 11) and P3NP was highest in patients with RA (7·7% and 6·1%, respectively) followed by patients with PSO (1·7% and 5·2%, respectively) and PsA (0·7% and 1·3%, respectively). Mean ± SD ELF scores for PSO, PsA and RA were, respectively, 9·09 ± 0·86, 8·96 ± 0·76 and 9·55 ± 1·04. All subgroups with moderate-to-severe disease severity had higher (> 9·8) ELF scores (PSO 27·0% vs. 18·3%; PsA 19·2% vs. 12%; RA 45·8% vs. 30·5%) and P3NP values. Distribution of the ELF score was smaller than the P3NP value [mean ± SD: 9·15 ± 0·92 (range 6·53-13·05) vs. 8·37 ± 4·30 (range 0·53-63·88)]. CONCLUSIONS: ELF score and P3NP are elevated in PSO, PsA and RA. ELF may be superior to P3NP alone, but further research should be done to validate the ELF test in determining susceptibility for developing liver fibrosis in PSO, PsA and RA.

Screening for liver fibrosis in the general population: a call for action.

Liver cirrhosis is one of the main causes of death and disability-adjusted life-years worldwide. Generally, cirrhosis develops after a long period of liver-cell injury that leads to the deposition of collagen, leading to progressive fibrosis and nodule formation in the liver tissue. Most patients are diagnosed in late stages when liver decompensation or liver cancer develops. The diagnosis is rarely made in early stages-when liver fibrosis is mild to moderate but cirrhosis is not yet established-because the disease is asymptomatic. No strategies for detection of liver fibrosis at these early stages have been developed, but therapies are more effective in early stages than late stages of chronic liver diseases, so enabling early detection is an important research topic. Non-invasive methods for assessing liver fibrosis have been developed, of which the most commonly used are transient elastography-which estimates liver fibrosis by measuring liver stiffness-and serum biomarkers of fibrosis. Studies have shown that 6-7% of the adult population without known liver disease have liver fibrosis, mostly associated with non-alcoholic fatty liver disease. These data suggest that programmes of screening for liver fibrosis in the general population should be assessed.

Immune selection of tumor cells in TCR ß-chain transgenic mice.

The concept of immunological surveillance implies that immunogenic variants of tumor cells arising in the organism can be recognized by the immune system. Tumor progression is provided by somatic evolution of tumor cells under the pressure of the immune system. The loss of MHC Class I molecules on the surface of tumor cells is one of the most known outcomes of immune selection. This study developed a model of immune selection based on the immune response of TCR 1d1 single ß-chain transgenic B10.D2(R101) (K(d)I(d)D(b)) mice to allogeneic EL4 (H-2(b)) thymoma cells. In wild-type B10.D2(R101) mice, immunization with EL4 cells induced a vigorous CTL response targeted to the H-2K(b) molecule and results in full rejection of the tumor cells. In contrast, transgenic mice developed a compromised proliferative response in mixed-lymphocyte response assays and were unable to reject transplanted allogeneic EL4 cells. During the immune response to EL4 cells, CD8(+) T-lymphocytes with endogenous ß-chains accumulated predominantly in the spleen of transgenic mice and only a small part of the T-lymphocytes expressing transgenic ß-chains became CD8(+)CD44(+)CD62L(-) effectors. Then, instead of a full elimination of tumor cells as in wild-type mice, a reproducible prolonged equilibrium phase and subsequent escape was observed in transgenic mice that resulted in death of 90% of the mice in 40-60 days after grafting. Prolonged exposure of tumor cells to the pressure of the immune system in transgenic mice in vivo resulted in a stable loss of H-2K(b) molecules on the EL4 cell surface. Genetic manipulation of the T-lymphocyte repertoire was sufficient to reproduce the classic pattern of interactions between tumor cells and the immune system, usually observed in reliable syngeneic models of anti-tumor immunity. This newly-developed model could be used in further studies of immunoregulatory circuits common for transplantational and anti-tumor immune responses.

The relationship between patients' experiences of continuity of cancer care and health outcomes: a mixed methods study.

It is difficult to define continuity of care or study its impact on health outcomes. This study took place in three stages. In stage I we conducted qualitative research with patients, their close relatives and friends, and their key health professionals from which we derived a number of self completion statements about experienced continuity that were tested for reliability and internal consistency. A valid and reliable 18-item measure of experienced continuity was developed in stage II. In stage III we interviewed 199 patients with cancer up to five times over 12 months to ascertain whether their experiences of continuity were associated with their health needs, psychological status, quality of life, and satisfaction with care. The qualitative data revealed that experienced continuity involved receiving consistent time and attention, knowing what to expect in the future, coping between service contacts, managing family consequences, and believing nothing has been overlooked. Transitions between phases of treatment were not associated with changes in experienced continuity. However, higher experienced continuity predicted lower needs for care, after adjustment for other potential explanatory factors (standardised regression coefficients ranging from -0.12 (95% CI -0.20, -0.05) to -0.32 (95% CI -0.41, -0.23)). Higher experienced continuity may be linked to lower health care needs in the future.

Separation of gas mixtures using a range of zeolite membranes: a molecular-dynamics study.

Gas separation efficiencies of three zeolite membranes (Faujasite, MFI, and Chabazite) have been examined using the method of molecular dynamics. Our investigation has allowed us to study the effects of pore size and structure, state conditions, and compositions on the permeation of two binary gas mixtures, O(2)N(2) and CO(2)N(2). We have found that for the mixture components with similar sizes and adsorption characteristics, such as O(2)N(2), small-pore zeolites are not suited for separations, and this result is explicable at the molecular level. For mixture components with differing adsorption behavior, such as CO(2)N(2), separation is mainly governed by adsorption and small-pore zeolites separate such gases quite efficiently. When selective adsorption takes place, we have found that, for species with low adsorption, the permeation rate is low, even if the diffusion rate is quite high. Our results further indicate that loading (adsorption) dominates the separation of gas mixtures in small-pore zeolites, such as MFI and Chabazite. For larger-pore zeolites such as Faujasite, diffusion rates do have some effect on gas mixture separation, although adsorption continues to be important. Finally, our simulations using existing intermolecular potential models have replicated all known experimental results for these systems. This shows that molecular simulations could serve as a useful screening tool to determine the suitability of a membrane for potential separation applications.

Human leucocyte antigen determinants of susceptibility to Barrett's oesophagus in Asians--a preliminary study.

BACKGROUND: Characteristic immune profiles have been demonstrated in gastro-oesophageal reflux disease. However, the genetic basis of gastro-oesophageal reflux disease remains unclear. AIM: To investigate whether certain human leucocyte antigen genes are associated with Barrett's oesophagus. METHODS: Asian patients of Malay, Chinese and Indian descent with Barrett's oesophagus (n = 59) and those without reflux symptoms and a normal oesophagus (n =60) were recruited prospectively using endoscopic and histopathological criteria. Human leucocyte antigen class I and II typing was performed using a polymerase chain reaction sequence-specific primers method. RESULTS: The HLA-B7 allele was present in 17% (10 of 59) of patients with Barrett's oesophagus when compared with 0% (zero of 60) of controls [P = 0.0006, corrected P = 0.0171, OR = 25.67]. Subgroup analysis revealed that the HLA-B7 allele was confined almost exclusively to Indians with Barrett's oesophagus, 43% (nine of 21) vs. 0% (zero of 19) Indian controls (P = 0.0014, corrected P = 0.0406, OR = 29.64). No class II associations, protective human leucocyte antigens or extended haplotypes for disease susceptibility were identified. CONCLUSIONS: Barrett's oesophagus in Asians, particularly Indians, is strongly positively associated with HLA-B7; reinforcing a genetic component to gastro-oesophageal reflux disease. A larger sample size and different ethnic populations should be genotyped to further confirm this association and identify possible additional risk factors in the human leucocyte antigen locus.

Molecular dynamics simulations of gas separations using faujasite-type zeolite membranes.

Gas separations with faujasite zeolite membranes have been examined using the method of molecular dynamics. Two binary mixtures are investigated, oxygen/nitrogen and nitrogen/carbon dioxide. These mixtures have been found experimentally to exhibit contrasting behavior. In O(2)/N(2) mixtures the ideal selectivity (pure systems) is higher than the mixture selectivity, while in N(2)/CO(2) the mixture selectivity is higher than the ideal selectivity. One of the key goals of this work was to seek a fundamental molecular level understanding of such divergent behavior. Our simulation results (using previously developed intermolecular models for both the gases and zeolites investigated) were found to replicate this experimental behavior. By examining the loading of the membranes and the diffusion rates inside the zeolites, we have been able to explain such contrasting behavior of O(2)/N(2) and N(2)/CO(2) mixtures. In the case of O(2)/N(2) mixtures, the adsorption and loading of both O(2) and N(2) in the membrane are quite competitive, and thus the drop in the selectivity in the mixture is primarily the result of oxygen slowing the diffusion of nitrogen and nitrogen somewhat increasing the diffusion of oxygen when they pass through the zeolite pores. In N(2)/CO(2) systems, CO(2) is rather selectively adsorbed and loaded in the zeolite, leaving very little room for N(2) adsorption. Thus although N(2) continues to have a higher diffusion rate than CO(2) even in the mixture, there are so few N(2) molecules in the zeolite in mixtures that the selectivity of the mixture increases significantly compared to the ideal (pure system) values. We have also compared simulation results with hydrodynamic theories that classify the permeance of membranes to be either due to surface diffusion, viscous flow, or Knudsen diffusion. Our results show surface diffusion to be the dominant mode, except in the case of N(2)/CO(2) binary mixtures where Knudsen diffusion also makes a contribution to N(2) transport.

Impact of human immunodeficiency virus (HIV) infection on the progression of liver fibrosis in hepatitis C virus infected patients.

OBJECTIVES: To compare the rate of hepatic fibrosis progression in hepatitis C virus (HCV) infected and human immunodeficiency virus (HIV)-HCV coinfected patients, and to identify factors that may influence fibrosis progression. PATIENTS AND METHODS: A total of 153 HCV infected and 55 HCV-HIV coinfected patients were identified from two London hospitals. Eligible patients had known dates of HCV acquisition, were HCV-RNA positive, and had undergone a liver biopsy, which was graded using the Ishak score. Univariate and multivariate logistic regression analyses were used to identify factors associated with fibrosis progression rate and the development of advanced fibrosis (stages 3 and 4). RESULTS: The estimated median fibrosis progression rate was 0.17 units/year (interquartile range (IQR) 0.10-0.25) in HIV-HCV coinfected and 0.13 (IQR 0.07-0.17) in HCV monoinfected patients (p=0.01), equating to an estimated time from HCV infection to cirrhosis of 23 and 32 years, respectively. Older age at infection (p<0.001), HIV positivity (p=0.019), higher alanine aminotransferase (ALT) level (p=0.039), and higher inflammatory activity (p<0.001) on first biopsy were all independently associated with more rapid fibrosis progression. ALT was correlated with histological index (r=0.35, p<0.001). A CD4 cell count < or =250 x 10(6)/l was independently associated with advanced liver fibrosis (odds ratio 5.36 (95% confidence interval 1.26-22.79)) and was also correlated with a higher histological index (r=-0.42, p=0.002). CONCLUSION: HIV infection modifies the natural history of HCV by accelerating the rate of fibrosis progression by 1.4 fold, and the development of advanced fibrosis threefold. A low CD4 cell count was independently associated with advanced disease and correlated with higher histological index, which suggests that early antiretroviral therapy may be of benefit in slowing HCV progression in coinfected patients.

Maternal periodontal disease and preterm low birthweight: case-control study.

Periodontal disease has been suggested to be an important risk factor for preterm low birthweight (PLBW). Here we report a case-control study of 236 cases (infants < 37 wks and weighing < 2499 g) and a daily random sample of 507 controls (> or = 38 wks and weighing > or = 2500 g). Clinical periodontal indices were measured on the labor wards. Associated risk factors for periodontal disease and PLBW were ascertained by means of a structured questionnaire and maternity notes. The risk for PLBW decreased with increasing pocket depth (odds ratio [OR] 0.83, 95% confidence interval [CI] 0.68 to 1.00). After adjustment for maternal age, ethnicity, maternal education, smoking, alcohol consumption, infections, and hypertension during pregnancy, this decreased further (OR 0.78, 95% CI 0.64 to 0.99). We found no evidence for an association between PLBW and periodontal disease. Our results do not support a specific drive to improve periodontal health of pregnant women as a means of improving pregnancy outcomes.

Skin prick test reactivity to foods in adult Malaysians with rhinitis.

The aim of the study was to determine the incidence of food and house dust mite (HDM) allergy in patients with nasal congestion and rhinorrhea attending the Otorhinolaryngology Clinic, National University of Malaysia, Kuala Lumpur. This was a prospective matched, controlled study of patients skin prick tested with commercial food and common aeroallergens. The participants were 148 Malaysian adults with symptoms of nasal congestion and rhinorrhea and 113 adult Malaysian control subjects without rhinitis symptoms. The skin prick test (SPT) was used to evaluate 11 foods common to the Malaysian diet and 3 HDM inhalants. Forty-eight percent of the patients with rhinitis had positive SPT results to foods, compared with 4.4% of control subjects (P < 0.05). The most commonly implicated foods were shrimp (48%) and rice (30%), which are common in the Malaysian diet. Seventy-two percent of rhinitis patients had positive SPT results to HDM, compared with 22.2% of control subjects (P < 0.05). Patients with rhinitis also had significantly more gastrointestinal problems than control subjects (P < 0.05). The incidences of HDM and food allergy are significantly greater in Malaysian adults with rhinitis symptoms than in control subjects without rhinitis. The effect of avoidance or immunotherapy awaits further study.

Deletion of cysteine 369 in lysyl hydroxylase 1 eliminates enzyme activity and causes Ehlers-Danlos syndrome type VI.

This study describes the relative contribution of the 10 cysteine residues in lysyl hydroxylase 1 (LH1) to enzyme activity. We have identified a novel mutation of a 15-bp deletion in exon 11 in one LH1 allele, that codes for amino acids 367-371 (DLCRQ), in two unrelated compound heterozygous patients with Ehlers-Danlos type VI. The mutations in their other alleles were a C1119T change (exon 10) and a predicted Q49X (exon 2). We confirmed that the loss of cysteine 369 in the deleted sequence contributed to the diminished enzyme activity by structure/function analysis of mutant LH1 constructs, in which C369 and the nine other cysteines were individually mutated to serine by site-directed mutagenesis of a normal pAcGP67/LH1cDNA construct. Following their expression in an Sf9 insect cell/baculovirus system, SDS-PAGE and Western analysis showed that equivalent levels of correctly-sized (85-kDa) products were secreted. The mutation of residues C369 and also C375, C552 and C687 virtually eliminated LH activity, whereas mutations of C267, C270, and C680 had an intermediate effect. In contrast, the C204S, C484S and C566S constructs had normal activity. Although disulfide bond formation may affect the relative contribution of each cysteine to LH activity, catalytic activity does not appear to be directly related to dimerization of the enzyme.

Oculocardiac reflex in the anophthalmic socket.

The oculocardiac reflex occurred in a patient with an anophthalmic socket undergoing surgery for inferior fornix shortening and laxity of the lower lid. This reflex occurs only rarely in anophthalmia; it has not been previously reported during socket surgery.

Induction of collagen synthesis by ascorbic acid. A possible mechanism.

L-Ascorbic acid stimulates procollagen synthesis in cultured human skin fibroblasts without appreciably altering noncollagen protein synthesis. The effect is unrelated to intracellular degradation of newly synthesized procollagen. Levels of mRNA for pro alpha 1(I), pro alpha 2(I), and pro alpha 1(III), measured by hybridization with the corresponding cDNA probes, are elevated in the presence of ascorbic acid, whereas the level of mRNA for fibronectin is unchanged. Levels of functional mRNA for procollagen, measured in a cell-free translation assay, are specifically increased in the presence of ascorbic acid. Thus, ascorbic acid appears to control the expression of three different procollagen genes, each of which is located on a separate chromosome. It is proposed that intracellularly accumulated procollagen in ascorbate deficiency may lead to a translational repression of procollagen synthesis. Ascorbic acid may relieve this block by promoting hydroxyproline formation and, consequently, secretion of procollagen from the cell. The increased level of procollagen mRNA under the influence of ascorbic acid may be secondary to increased synthesis of procollagen polypeptides; the control point may be gene transcription or mRNA degradation.

Regulation of collagen synthesis by ascorbic acid.

After prolonged exposure to ascorbate, collagen synthesis in cultured human skin fibroblasts increased approximately 8-fold with no significant change in synthesis of noncollagen protein. This effect of ascorbate appears to be unrelated to its cofactor function in collagen hydroxylation. The collagenous protein secreted in the absence of added ascorbate was normal in hydroxylysine but was mildly deficient in hydroxyproline. In parallel experiments, lysine hydroxylase (peptidyllysine, 2-oxoglutarate:oxygen 5-oxidoreductase, EC 1.14.11.4) activity increased 3-fold in response to ascorbate administration whereas proline hydroxylase (prolyl-glycyl-peptide, 2-oxoglutarate:oxygen oxidoreductase, EC 1.14.11.2) activity decreased considerably. These results suggest that collage polypeptide synthesis, posttranslational hydroxylations, and activities of the two hydroxylases are independently regulated by ascorbate.