The immunogenetics of primary biliary cirrhosis: A comprehensive review.

Primary biliary cirrhosis (PBC), a classic autoimmune liver disease, is characterised by a progressive T cell predominant lymphocytic cholangitis, and a serologic pattern of reactivity in the form of specific anti-mitochondrial antibodies (AMA). CD4+ T cells are particularly implicated by PBC's cytokine signature, the presence of CD4+ T cells specific to mitochondrial auto-antigens, the expression of MHC II on injured biliary epithelial cells, and PBC's coincidence with other similar T cell mediated autoimmune conditions. CD4+ T cells are also central to current animal models of PBC, and their transfer typically also transfers disease. The importance of genetic risk to developing PBC is evidenced by a much higher concordance rate in monozygotic than dizygotic twins, increased AMA rates in asymptomatic relatives, and disproportionate rates of disease in siblings of PBC patients, PBC family members and certain genetically defined populations. Recently, high-throughput genetic studies have greatly expanded our understanding of the gene variants underpinning risk for PBC development, so linking genetics and immunology. Here we summarize genetic association data that has emerged from large scale genome-wide association studies and discuss the evidence for the potential functional significance of the individual genes and pathways identified; we particularly highlight associations in the IL-12-STAT4-Th1 pathway. HLA associations and epigenetic effects are specifically considered and individual variants are linked to clinical phenotypes where data exist. We also consider why there is a gap between calculated genetic risk and clinical data: so-called missing heritability, and how immunogenetic observations are being translated to novel therapies. Ultimately whilst genetic risk factors will only account for a proportion of disease risk, ongoing efforts to refine associations and understand biologic links to disease pathways are hoped to drive more rational therapy for patients.

The impact of haemodilution and bypass pump flow on cerebral oxygen desaturation during cardiopulmonary bypass--A comparison of two systems of cardiopulmonary bypass.

OBJECTIVE: To determine the influence of haemodilution, bypass flow rates and calculated oxygen delivery during cardiopulmonary bypass (CPB) with either a conventional CPB (C-CPB) circuit or a miniaturised (Mini-CPB) circuit on cerebral oxygen desaturation. The effect of minimal haemodilution with a Mini-CPB was investigated. PARTICIPANTS: Eighty patients scheduled for elective cardiac surgery. INTERVENTION: Oxygenated haemoglobin (O2Hb) and tissue oxygenation index (TOI) were measured with near-infrared spectroscopy (NIRS). RESULTS: The average indexed bypass pump flow was significantly lower with Mini-CPB. When combined with haemoglobin concentration, the average oxygen delivery was the same between groups. Patients in the C-CPB group had a greater duration and severity of cerebral desaturation to a level <20% below baseline values, but none reached the depth and duration of the cerebral desaturation associated with poor outcome. Cerebral oxygen desaturation with C-CPB was significantly associated with low flows during bypass, whereas desaturation with Mini-CPB was associated with low perioperative haemoglobin concentration.

Are we there yet? The state of the evidence base for guidelines on breaking bad news to cancer patients.

The way clinicians break bad news to cancer patients has been retrospectively associated with poor psychosocial outcomes for patients. Education and practice in breaking bad news may be ineffective for improving patients' well-being unless it is informed by a sound evidence base. In the health field, research efforts are expected to advance evidence over time to inform evidence-based practice. Key characteristics of an advancing evidence base are a predominance of new data, and rigorous intervention studies which prospectively demonstrate improved outcomes. This review aimed to examine the progress of the evidence base in breaking bad news to cancer patients. Manual and computer-based searches (Medline and PsycINFO) were performed to identify publications on the topic of breaking bad news to cancer patients published between January 1995 and March 2009. Relevant publications were coded in terms of whether they provided new data, examined psychosocial outcomes for patients or tested intervention strategies and whether intervention studies met criteria for design rigour. Of the 245 relevant publications, 55.5% provided new data and 16.7% were intervention studies. Much of the intervention effort was directed towards improving provider skills rather than patient outcomes (9.8% of studies). Less than 2% of publications were rigorous intervention studies which addressed psychosocial outcomes for patients. Rigorous intervention studies which evaluate strategies for improving psychosocial outcomes in relation to breaking bad news to cancer patients are needed. Current practice and training regarding breaking bad news cannot be regarded as evidence-based until further research is completed.

Symptomatic atrial arrhythmias and transcatheter closure of atrial septal defects in adult patients.

OBJECTIVE: To determine whether transcatheter device closure of a secundum atrial septal defect (ASD) will reduce the risk of developing subsequent atrial arrhythmias. DESIGN: The incidence and predictors of symptomatic atrial tachyarrhythmias (AT) were examined in adults undergoing transcatheter closure of ASDs. SETTING: Toronto Congenital Cardiac Centre for Adults. PATIENTS: 132 consecutive patients, mean (SD) age 44 (16) years; 74% female. MAIN OUTCOME MEASURE: Sustained or symptomatic atrial arrhythmias at early follow up (six weeks; n = 115) and intermediate follow up (last clinic visit 17 (11) months post surgery; n = 121). RESULTS: 15% of the patients (20 of 132) had AT before the procedure (14 paroxysmal, six persistent). Patients without a history of arrhythmia had a low incidence of AT during early follow up (6%) and intermediate follow up (1%/year), while all patients with persistent AT before closure remained in atrial fibrillation or flutter. Of patients in sinus rhythm but with a previous history of AT, two thirds remained arrhythmia-free at follow up, with overall incidences of paroxysmal and persistent AT of 17%/year and 11%/year. A history of AT before closure (risk ratio (RR) 35.0, 95% confidence interval (CI) 7.2 to 169.0) and age > or = 55 years at the time of device insertion (RR 5.6, 95% CI 1.2 to 25.0) predicted AT after closure. CONCLUSIONS: Device closure of an ASD before the onset of atrial arrhythmias may protect against the subsequent development of arrhythmia, in particular in patients less than 55 years of age.

Insulinoma presenting with hyperandrogenism: a case report and a literature review.

An 18-year-old woman presented with a 6-month history of amenorrhoea and hyperandrogenism. Three months later she developed several episodes of fasting hypoglycaemia and was subsequently diagnosed with an insulinoma. Hyperinsulinaemia was observed in association with an elevated serum testosterone level. Surgical removal of the insulinoma resulted in resolution of the clinical and biochemical features of the polycystic ovarian syndrome (PCOS). Polycystic ovarian syndrome is unusual in a patient having an insulinoma. The rarity of this association may be the result of the late age of onset of this type of tumour, intermittent secretion of excessive insulin by the tumour, the degree of hyperinsulinism or other factors extrinsic to the insulin receptor that may facilitate insulin activity. However, we could not discover how our patient differs in having had PCOS from the majority of women with insulinoma who do not. If other patients with insulinoma are subsequently found to have hyperandrogenism, then this tumour might be added to the differential diagnosis of causes of anovulatory cycles and hyperandrogenaemia, although rare the association would be uncommon.

Toll-like receptors 2 and 4 are up-regulated during intestinal inflammation.

BACKGROUND & AIMS: Bacterial wall products play an important role in the activation of immune and nonimmune cells of the intestinal mucosa. Toll-like receptors (TLRs) TLR2 and TLR4 have been identified as signaling receptors activated by bacterial wall components. METHODS: Expression of TLRs in human intestinal mucosa obtained by endoscopy and surgery was analyzed by immunohistochemistry. Intestinal macrophages were isolated by immunomagnetic beads armed with a CD33 antibody. Reverse-transcription polymerase chain reaction was performed for TLR1-5. Results were confirmed by Northern blot and flow cytometry. Interleukin-1beta messenger RNA (mRNA) was quantified by a polymerase chain reaction-enzyme-linked immunosorbent assay-kit. RESULTS: Immunohistochemistry revealed a significant increase in the TLR2 and TLR4 antigen expression on submucosal cells in inflamed intestinal mucosa compared with non-inflamed mucosa. TLR expression was localized in intestinal macrophages by double-labeling techniques. No TLR-polymerase chain reaction product could be obtained with mRNA from CD33-positive macrophages from normal mucosa. We observed an induction of mRNA for TLR2, TLR4, and TLR5 in inflammation-associated macrophages. TLR1 and TLR3 were only detectable in blood monocytes. Monocytes reacted to lipopolysaccharide stimulation with a 3-fold and in vitro differentiated macrophages with a 16-fold increase of cellular interleukin-1beta mRNA. Macrophages from normal mucosa did not respond to lipopolysaccharide showing the functional relevance of TLR expression. CONCLUSIONS: This study shows the inflammation-dependent induction of TLR2 and TLR4 expression in intestinal macrophages. The absence of TLRs abolishes the reactivity of mucosal macrophages to bacterial wall products. Presence of TLRs may thereby contribute to the inflammatory process.

Dynamics of bacterial phenotype selection in a colonized host.

The population dynamics of Helicobacter pylori during colonization in an infected animal host provide a quantifiable experimental model of in vivo microbial phenotype evolution. Phenotype variability in H. pylori populations can be typed as polymorphic expression of Lewis antigens on their cell surfaces. The high mutational frequency of H. pylori for Lewis expression provides substrate for differential selection by the host. Experimental challenge and successful colonization of mice and gerbils allows tracking of H. pylori phenotype variability from the initial inoculation to the ultimate establishment of a quasispecies. Colonization data provide a quantitative experimental model of phenotype evolution in a relatively large population (>10(4) individuals) over a relatively long evolutionary time scale (>10(3) generations). A mathematical model is developed to interpret the data in terms of the dynamic processes occurring during colonization. The mathematical model distinguishes the roles of selection and mutation; quantifies the effects of initial phenotype diversity, mutational frequency, and selective advantage; and applies generally to phenotype evolution in biological populations.

Mannitol in cardioplegia as an oxygen free radical scavenger measured by malondialdehyde.

Oxygen free radicals (OFRs) are associated with ischaemia-reperfusion injury involving many organs, including the heart, which can lead to depressed cardiac function and abnormalities in the cardiac ultrastructure. This is seen upon the release of the aortic crossclamp when the ischaemic myocardium is reperfused in patients undergoing cardiopulmonary bypass (CPB). Various studies have shown that by adding OFR scavenging agents or antioxidants to the CPB prime or cardioplegia, cardiac performance improves. Mannitol is an osmotic diuretic with free radical scavenging properties, which has been shown to reduce the extent of ischaemic injury and improve the function of the myocardium. This study evaluated how effective mannitol is as an OFR scavenger by administering different concentrations of cardioplegia antegrade into the aortic root, thus maximising its effects directly upon the myocardium rather than being diluted in the CPB prime. Thirty-three patients undergoing primary coronary artery bypass grafting (CABG) were, by double blind random selection, allocated into one of three groups: group 1, a control group (consisting of 11 patients) receiving no mannitol; group 2 (11 patients), receiving a concentration of 4 g/l; and group 3 (11 patients), receiving 8 g/l. Three blood samples were taken directly from the coronary sinus during bypass: the first sample at the start of bypass, just prior to the crossclamp being applied; the second sample just after removal of the crossclamp; and the third sample just prior to termination of bypass. All samples were then centrifuged and the plasma analysed for malondialdehyde (MDA) using high-performance liquid chromatography (HPLC). MDA, an endproduct of lipid peroxidation, causes cellular damage and disruption of cell membranes when tissue antioxidants are exhausted. The more MDA produced, the greater the depletion of tissue antioxidants secondary to OR formation during reperfusion when the aortic crossclamp is removed. HPLC is a useful biochemical study; however, it is not a direct indicator of depressed myocardial function, such as an invasive test would be, and this should be borne in mind. Statistically, the results do not show a significant difference among the three groups or among the three samples. However, a trend can be seen, which shows lower levels of MDA in the two groups receiving mannitol and there is an indication of a rise in MDA levels upon the start of reperfusion in the two groups receiving mannitol, but not the control group. It is concluded that further samples would be needed to find a significant difference in MDA concentrations.

The Fontan procedure in adults.

SETTING: Tertiary adult congenital cardiac referral centre. DESIGN: Retrospective cross sectional analysis. OBJECTIVES: To report our 20 year experience with adult Fontan operations, and to compare late outcome in patients with single ventricle with definitive aortopulmonary or cavopulmonary shunt palliation. PATIENTS AND MAIN OUTCOME MEASURES: Patients older than 18 years undergoing Fontan operation between 1 January 1982 and 31 December 1998 were identified. Mortality and late outcome were derived from hospital records. These patients were compared with a cohort of 50 adults with single ventricle who had not undergone a Fontan operation. RESULTS: 61 adults, median age 36 years (range 18-47 years), with a median follow up of 10 years (range 0-21 years) were identified. Actuarial survival was 80% at one year, 76% at five years, 72% at 10 years, and 67% at 15 years. Compared with before the Fontan operation, more patients were in New York Heart Association (NYHA) functional class I or II at the latest follow up (80% v 58%, p < 0.001). Systolic ventricular function deteriorated during follow up such that 34% had moderate to severe ventricular dysfunction at the latest follow up compared with 5% before Fontan (p < 0.001). Arrhythmia increased with time (10% before Fontan v 57% after 10 years, p < 0.001). Fontan patients had improved NYHA functional class, ventricular function, atrioventricular regurgitation, and fewer arrhythmias than the non-Fontan group at the latest follow up. CONCLUSION: The Fontan operation in adults has acceptable early and late mortality. Functional class, systolic ventricular function, atrioventricular regurgitation, and arrhythmia deteriorate late after surgery but to a lesser degree than in non-Fontan patients with a single ventricle.

Characterization of the Epha1 receptor tyrosine kinase: expression in epithelial tissues.

The Eph family of receptor tyrosine kinases plays a crucial role during development and is implicated in oncogenesis. Using a partial cDNA clone of an Eph-related kinase (Esk) we isolated the complete coding region of a gene which we show to be murine EphA1 by both structural and functional criteria. The chromosomal localization is shown to be syntenic to hEphA1 and the genomic organization also shows distinct features found in the hEphA1 gene. Functionally, in keeping with findings for the human homologue, both soluble recombinant and "native" mEphA1 show preferential binding to ephrin A1. However, we also observed significant binding to other A-type ligands as has been observed for other Eph receptors. We analysed the expression of mEphA1 mRNA by in situ hybridization on tissue sections. mEphA1 was expressed in epithelial elements of skin, adult thymus, kidney and adrenal cortex. Taken together with previous Northern blotting data these results suggest that mEphA1 is expressed widely in differentiated epithelial cells.

Results of aortic valve-sparing operations.

OBJECTIVE: To review the late results of valve-sparing operations in patients with aortic root aneurysm and in those with ascending aortic aneurysm and aortic insufficiency. METHODS: From May 1988 to June 2000, 120 patients with aortic root aneurysm and 68 with ascending aortic aneurysm and aortic insufficiency underwent aortic valve-sparing operations. Patients with aortic root aneurysm were younger, were predominantly male, and had less severe aortic insufficiency than patients with ascending aortic aneurysm, who were older and often had aneurysm of the transverse arch. Forty-eight patients with aortic root aneurysm had the Marfan syndrome. The prevalence of aortic dissection was similar in both groups. Reconstruction of the aortic root was performed by reimplanation of the aortic valve in 64 patients and by remodeling of the aortic root in 56. Patients with ascending aortic aneurysm and aortic insufficiency were treated by replacement of the ascending aorta with reduction in the diameter of the sinotubular junction. Approximately two thirds of the latter patients also required replacement of the transverse aortic arch. The mean follow-up was 35 +/- 31 months for patients with aortic root aneurysm and 26 +/- 23 months for those with ascending aortic aneurysm. RESULTS: There were 2 operative and 5 late deaths in patients with aortic root aneurysm and 1 operative and 9 late deaths in patients with ascending aortic aneurysm. The 5-year survival for patients with aortic root aneurysm was 88% +/- 4% and for patients with ascending aortic aneurysm, 68% +/- 12% (P =.01). Severe aortic insufficiency developed in 2 patients, and they required aortic valve reoperation. The 5-year freedom from aortic valve reoperation was 99% +/- 1% for patients with aortic root aneurysm and 97% +/- 4% for those with ascending aortic aneurysm. Seven patients had moderate aortic insufficiency at the latest echocardiographic study. The 5-year freedom from severe or moderate aortic insufficiency was 90% +/- 4% in patients who had aortic root aneurysm and 98% +/- 2% in those who had ascending aortic aneurysm. CONCLUSIONS: Aortic valve-sparing operations have provided excellent clinical outcomes and few valve-related complications. The function of the reconstructed aortic root remains unchanged in most patients during the first 5 years of follow-up.

Full-thickness burn of the foot: successful treatment with Apligraf. A case report.

Burn wounds, although uncommon in the foot, present a uniquely challenging opportunity to physicians. The keys to successful management include a proper and specific initial evaluation of the burning agent, the location, the TBSA affected, and the depth. Ultimately, proper recognition and meticulous wound care with skin grafting, when necessary, bring about the desired results. A case report of a patient with a third-degree burn over the dorsum of the left foot is presented. This case is unique in that Apligraf, a human skin equivalent, was used to gain coverage and eventual resolution of the wound. It is the authors' opinion that the use of Apligraf in this application is a viable alternative to traditional methods of skin harvesting and grafting. To the authors' knowledge, there have been no other cases reported of Apligraf use in burn wound coverage of the foot.

Organization and chromosomal localization of the murine Testisin gene encoding a serine protease temporally expressed during spermatogenesis.

The recently characterized human serine protease, Testisin, is expressed on premeiotic testicular germ cells and is a candidate type II tumor suppressor for testicular cancer. Here we report the cloning, characterization and expression of the gene encoding mouse Testisin, Prss21. The murine Testisin gene comprises six exons and five introns and spans approximately 5 kb of genomic DNA with an almost identical structure to the human Testisin gene, PRSS21. The gene was localized to murine chromosome 17 A3.3-B; a region syntenic with the location of PRSS21 on human chromosome 16p13.3. Northern blot analyses of RNA from a range of adult murine tissues demonstrated a 1.3 kb mRNA transcript present only in testis. The murine Testisin cDNA shares 65% identity with human Testisin cDNA and encodes a putative pre-pro-protein of 324 amino acids with 80% similarity to human Testisin. The predicted amino-acid sequence includes an N-terminal signal sequence of 27 amino acids, a 27 amino-acid pro-region, a 251 amino-acid catalytic domain typical of a serine protease with trypsin-like specificity, and a C-terminal hydrophobic extension which is predicted to function as a membrane anchor. Immunostaining for murine Testisin in mouse testis demonstrated specific staining in the cytoplasm and on the plasma membrane of round and elongating spermatids. Examination of murine Testisin mRNA expression in developing sperm confirmed that the onset of murine Testisin mRNA expression occurred at approximately day 18 after birth, corresponding to the appearance of spermatids in the testis, in contrast to the expression of human Testisin in spermatocytes. These data identify the murine ortholog to human Testisin and demonstrate that the murine Testisin gene is temporally regulated during murine spermatogenesis.

Sustained atrial arrhythmias in adults late after repair of tetralogy of fallot.

We determined the prevalence of sustained atrial tachyarrhythmia (AT) in adults late after repair of tetralogy of Fallot (ToF) and examined its impact on subsequent heart failure, reoperation, and mortality. Ventricular arrhythmias are associated with increased morbidity and mortality in patients with repair of ToF. The clinical impact of AT in this population has not been established. A retrospective cohort study of 242 patients with repaired ToF identified 29 patients (prevalence of 12%) with sustained episodes of AT. Patients with repaired ToF but without sustained arrhythmia (n = 213) constituted a comparison group. Baseline characteristics and clinical outcomes in the 2 groups were compared. An echocardiographic analysis compared 15 patients with AT and 15 matched for age at operation and timing of echocardiography. The development of AT was associated with substantial morbidity including congestive heart failure, reoperation, subsequent ventricular tachycardia, stroke, and death (combined events, 20 of 29 patients [69%]). The rate of combined events (congestive heart failure, stroke, and deaths) in the 213 "arrhythmia-free" patients was 30% (64 of 213 patients). Event-free survival after repair was 18 +/- 2 years for the AT group and 28 +/- 1 years for the arrhythmia-free group (p < 0.001). Patients with AT were older at surgical repair (25 +/- 16 vs 10 +/- 9 years, p = 0.001), and at most recent assessment were aged 48 +/- 12 vs 32 +/- 10 years (p = 0.001). The AT group had a higher mean right atrial volume and proportion of significant pulmonary regurgitation than matched controls. The development of AT in the adult late after ToF repair identifies patients at risk and is associated with older age at repair, a higher frequency of hemodynamic abnormalities, and increased morbidity.

Care of adults with congenital heart disease--a challenge for the new millennium.

The care of complex congenital heart defect (CHD) patients should be continuous through life. Medium- and high-risk patients should be seen in special facilities for grown-up congenital heart (GUCH) patients, and followed for life. CHD in the adult is different than CHD in the child. Transitional programs should be available to prepare the adolescent patient to take charge of his/her own health. The patient should be transferred smoothly from pediatric to adult care. GUCH care should be regionally anchored in special facilities (groups or sometimes individuals) willing to make a commitment to their care. Ideally, pediatric and adult cardiologists will collaborate. GUCH care should be multidisciplinary wherever possible--and certainly in supraregional centers. Surgery, diagnostic catheterization, interventional cath procedures, EP management, and even MRI should be done in selected centers with high quality services for all cases other than the most simple lesions. Care should be available at all times. Surgeons who operate on children with similar conditions should perform the most GUCH surgery. GUCH surgery should be performed in centers with adequate institutional and individual surgeon's volumes. In determining which surgeons and units have adequate volumes, both pediatric and adult volumes should be combined.

Gene structure alternative splicing, and chromosomal localization of pro-apoptotic Bcl-2 relative Bim.

Bim is a proapoptotic protein of the Bcl-2 family that shares only the short BH3 domain with other members. It has three isoforms, apparently produced by alternative splicing. The demonstration that Bim is essential for certain apoptotic responses and to prevent overproduction of hematopoietic cells suggests that it may be a tumor suppressor. We have, therefore, investigated the organization of the mouse Bim gene, delineating its promoter and splicing, and positioned the gene on both mouse and human chromosomes. Bim has six exons, but the third is a facultative intron that is spliced out in the mRNAs for the smaller isoforms (BimL and BimS), but not that encoding the largest isoform (BimEL). The 0.8-kb region 5' to exon 1, which contains a TATA-less promoter and binding sites for several transcription factors, can drive expression of a reporter gene. Mouse Bim localizes to the distal third of Chromosome (Chr) 2, near the F-G boundary, and its human counterpart to Chr 2q12 or q13. Deletions of these bands have been reported in ten tumors (eight hematopoietic), reinforcing the possibility that Bim is a tumor suppressor. These findings should help to clarify the regulation of Bim expression and to assess whether mutations involving Bim contribute to neoplastic and other diseases.

Lung function and aerobic capacity in adult patients following modified Fontan procedure.

OBJECTIVE: To examine cardiopulmonary performance in 52 adult patients with a Fontan circulation. DESIGN: Retrospective cohort study. Values of maximum oxygen uptake (VO(2)max), maximum heart rate (HRmax), forced vital capacity (FVC), and forced expiratory volume in one second (FEV(1)) were compared with predictive values for different age groups. Patients were further subdivided into those with a pulmonary artery connection (RA-PA) or right atrium to right ventricle conduit (RA-RV). RESULTS: At late follow up (median 10 years, range 1 to 26 years), patients with Fontan circulation had greatly diminished VO(2)max, HRmax, FVC, and FEV(1) compared with predicted values. Early age at surgery had a positive impact on aerobic capacity. The FEV(1):FVC ratio indicated restrictive lung function. No differences were found with respect to any variable between patients with RA-PA connections and those with RA-RV connections. CONCLUSIONS: Patients with a Fontan circulation have greatly diminished values of aerobic capacity and a restrictive pattern of lung function. Patients with an early surgical procedure obtained higher values of VO(2)max. The theoretical benefits of including the right ventricle in a Fontan circulation were not apparent.