Utility and cost evaluation of multiparametric magnetic resonance imaging for the assessment of non-alcoholic fatty liver disease.

BACKGROUND: Validated diagnostic tools that are accurate, cost effective and acceptable to patients are required for disease stratification and monitoring in NAFLD. AIMS: To investigate the performance and cost of multiparametric MRI alongside existing biomarkers in the assessment of NAFLD. METHODS: Adult patients undergoing standard of care liver biopsy for NAFLD were prospectively recruited at two UK liver centres and underwent multiparametric MRI, blood sampling and transient elastography withing 2 weeks of liver biopsy. Non-invasive markers were compared to histology as the gold standard. RESULTS: Data were obtained in 50 patients and 6 healthy volunteers. Corrected T1 (cT1) correlated with NAFLD activity score (ρ = 0.514, P < .001). cT1, enhanced liver fibrosis (ELF) test and liver stiffness differentiated patients with simple steatosis and NASH with AUROC (95% CI) of 0.69 (0.50-0.88), 0.87 (0.77-0.79) and 0.82 (0.70-0.94) respectively and healthy volunteers from patients with AUROC (95% CI) of 0.93 (0.86-1.00), 0.81 (0.69-0.92) and 0.89 (0.77-1.00) respectively. For the risk stratification of NAFLD, multiparametric MRI could save £150,218 per 1000 patients compared to biopsy. Multiparametric MRI did not discriminate between individual histological fibrosis stages in this population (P = .068). CONCLUSIONS: Multiparametric MRI accurately identified patients with steatosis, stratifies those with NASH or simple steatosis and reliably excludes clinically significant liver disease with superior negative predictive value (83.3%) to liver stiffness (42.9%) and ELF (57.1%). For the risk stratification of NAFLD, multiparametric MRI was cost effective and, combined with transient elastography, had the lowest cost per correct diagnosis.

Complementary DNA cloning of the alternatively expressed endothelial cell glycoprotein Ib beta (GPIb beta) and localization of the GPIb beta gene to chromosome 22.

Glycoprotein Ib beta (GPIb beta) exists in platelets disulfide-linked to glycoprotein Ib alpha (GPIb alpha), a major receptor for von Willebrand factor. Both GPIb alpha and GPIb beta are expressed in endothelial cells (EC). While the GPIb alpha mRNA and protein appear similar in platelets and EC, EC GPIb beta mRNA is larger than platelet GPIb beta and encodes a larger protein. We have cloned and sequenced EC GPIb beta cDNA and report a 2793-nucleotide sequence which contains a 411-amino acid open reading frame. The EC sequence contains all of the platelet cDNA sequence and all but three amino acids of the primary translation product. Like the genes encoding GPIb alpha, GPIX, and GPV, the GPIb beta gene appears simple in structure. Using human hamster hybrids, we have localized the GPIb beta gene to chromosome 22pter-->22q11.2. When we examined poly (A)+ RNA from several human tissues for GPIb beta mRNA expression, we found that GPIb beta mRNA was expressed in a variety of tissues but was most abundant in heart and brain, while GPIb alpha and GPIX mRNA expression was found only in lung and placenta at very low levels. The broad distribution of GPIb beta mRNA suggests that it may be playing a role different than or additional to its function in platelets.

Erratum to: 2016 WSES guidelines on acute calculous cholecystitis.

[This corrects the article DOI: 10.1186/s13017-016-0082-5.].

2016 WSES guidelines on acute calculous cholecystitis.

Acute calculus cholecystitis is a very common disease with several area of uncertainty. The World Society of Emergency Surgery developed extensive guidelines in order to cover grey areas. The diagnostic criteria, the antimicrobial therapy, the evaluation of associated common bile duct stones, the identification of "high risk" patients, the surgical timing, the type of surgery, and the alternatives to surgery are discussed. Moreover the algorithm is proposed: as soon as diagnosis is made and after the evaluation of choledocholitiasis risk, laparoscopic cholecystectomy should be offered to all patients exception of those with high risk of morbidity or mortality. These Guidelines must be considered as an adjunctive tool for decision but they are not substitute of the clinical judgement for the individual patient.

Characterization of p53 mutations in colorectal liver metastases and correlation with clinical parameters.

The presence and type of mutations of the p53 tumor suppressor gene were determined in 40 patients undergoing curative hepatic resection for metastatic colorectal carcinoma. This represents the largest series in the literature on the screening of p53 mutations for liver metastases. The analysis was performed in exons 5-9 by denaturing gradient gel electrophoresis followed by direct sequencing. Forty-five percent of tumors showed mutation in p53, and this was observed only in exons 5-8. Mutations at codon positions 167, 196, 204, 213, 245, 281, 282, 286, and 306; deletion of codon 251 and of the first nucleotide of codon 252; and Leu residue (CTC) insertion downstream codon 252 are reported for the first time in colorectal liver metastasis. Mutations at codon positions 163, 248, and 273 have been reported previously. Correlation of p53 status with clinical parameters showed that patients with mutated p53 had a statistically higher number of lesions when compared with patients with wild-type p53 (P<0.050). In particular, of patients with mutated p53, 41% had three or more metastases compared with 14% of patients with wild-type p53. Synchronous metastases were present in 70% of the patients with p53 mutations and in only 29% of patients with wild-type p53 (P<0.025). In addition, patients with p53 mutations are more likely to develop recurrence (73%) compared with patients with wild-type p53 (33%; P<0.001). Other factors considered, including preoperative carcinoembryonic antigen level, bilobar distribution, and size of the lesion(s), did not show significant correlation with p53 status. These results suggest that p53 status might be an important prognostic indicator to predict the pattern and likelihood of treatment failure after hepatic resection.

Preirradiation PSA predicts biochemical disease-free survival in patients treated with postprostatectomy external beam irradiation.

PURPOSE: To assess the clinical outcome and prostate-specific antigen (PSA) response and to determine prognostic factors for biochemical disease-free survival in patients treated with external beam radiotherapy following radical prostatectomy without hormonal therapy. METHODS AND MATERIALS: Forty-eight patients were treated after prostatectomy with radiotherapy between March, 1988 and December, 1993. Seven patients had undetectable PSA (<0.2) and the remainder had detectable PSA at the time of irradiation (overall: median 2.7, range 0-24.9). Nine patients had biopsy proven local recurrence, palpable local disease, or positive preirradiation imaging. No patients received hormonal therapy prior to irradiation. Median follow-up was 55 months. A median dose of 60 Gy (range 58-66) was given to the prostate bed. Survival was analyzed using the life-table method. Actuarial biochemical disease-free survival was the primary endpoint studied. RESULTS: In patients with detectable PSA, 51% had levels return to undetectable after irradiation. The actuarial 5-year freedom from biochemical failure for all patients was 24%. A significant difference in biochemical disease-free survival was seen for patients irradiated with preirradiation PSA that was undetectable (p < 0.001), or preirradiation PSA that was < or =2.7 (p = 0.002), vs. preirradiation PSA that was >2.7. Five-year actuarial biochemical disease-free survival values were 71, 48, and 0%, respectively, for the three groups. Biochemical disease-free survival was not affected by preoperative PSA level, clinical stage, Gleason's score, pathologic stage, surgical margins, presence of undetectable PSA after surgery, surgery to radiation interval, total dose, or presence of clinically suspicious local disease. Based on digital rectal exam, there were no local failures. CONCLUSION: Biochemical disease-free survival after postprostatectomy radiation is predicted by the PSA at the time of irradiation. Clinical local control is excellent, but distant failure remains a significant problem in this population. The addition of concomitant systemic therapy should be investigated in patients with PSA >2.7.

Unusual sinonasal small-cell neoplasms following radiotherapy for bilateral retinoblastomas.

Two patients developed sinonasal small-cell neoplasms that arose 22 years and 37 years, respectively, following radiotherapy for bilateral retinoblastomas. The tumors were composed of small cells with scant cytoplasm and had a few scattered Homer-Wright rosettes. Immunohistochemically, one tumor was positive for keratin (CAM 5.2 and AE1/AE3), epithelial membrane antigen, and neuron-specific enolase. The other neoplasm was immunoreactive for keratin (CAM 5.2 only) and neuron-specific enolase; it also had focal immunopositivity for S-100 protein, desmin, and muscle-specific actin. Both were negative for CEA, vimentin, melanocyte-specific antigen (HMB45), chromogranin A, synaptophysin, Leu-7, 200 kd neurofilament, and retinal S-antigen. Despite aggressive multimodal therapy, the patients died of metastatic tumor 7 months and 10 months following their initial diagnosis, respectively. Although osteosarcoma is the most frequent second cancer following bilateral retinoblastomas, some patients develop clinically aggressive sinonasal small-cell tumors that are difficult to place into conventional classifications. Both of our cases showed evidence of multidirectional differentiation; one tumor labeled with epithelial and neural markers, and the other expressed epithelial, neural, and myogenous antigens.

WIN 63480, a hydrophilic TCP-site ligand, has reduced agonist-independent NMDA ion channel access compared to MK-801 and phencyclidine.

NMDA channel blockers are potentially advantageous therapeutic agents for the treatment of ischemia and head trauma, which greatly elevate extracellular glutamate, because they should most effectively inhibit high levels of receptor activation. A novel high affinity TCP site ligand, WIN 63480, does not produce MK-801- or PCP-like behavioral activation at anti-ischemic doses. While WIN 63480, MK-801 and PCP were all observed to be effective blockers of open NMDA channels, WIN 63480 had much less access to closed NMDA channels. This difference may be due to the fact that WIN 63480 is hydrophilic (logD = -4.1) while MK-801 and PCP are lipophilic (logD = +1.8). In vivo, closed channel access may result in a non-competitive profile of antagonism for MK-801 and PCP compared to a more uncompetitive profile for WIN 63480. Release of glutamate, and depolarization, are likely to produce a high level of NMDA receptor activation in ischemic areas compared to normal tissue. Consequently, at anti-ischemic doses, WIN 63480 may produce less inhibition of physiological NMDA-mediated processes in neural systems involved in behavioral regulation than MK-801 or PCP, leading to an improved side effect profile.

Novel benzo[b]quinolizinium cations as uncompetitive N-methyl-D-aspartic acid (NMDA) antagonists: the relationship between log D and agonist independent (closed) NMDA channel block.

A series of permanently charged benzo[b]quinolizinium cations having lower lipophilicity than MK-801 or phencyclidine (PCP) were synthesized. Data relating agonist independent block of N-methyl-D-aspartic acid (NMDA) ion channels to log D are described. Closed channel access is predicted to result in a more noncompetitive profile of antagonism compared to selective open channel blockers, which are uncompetitive inhibitors. Reduced closed channel block may underlie the absence of PCP or MK-801-like behavioral side effects observed for benzo[b]-quinolizinium cations.

Weaning-induced development of delta-opioid receptors in rat brain: differential effects of guanine nucleotides and sodium upon ligand-receptor recognition.

1. We have previously shown that weaning at day 21 increases delta-opioid receptor binding in the brain at day 25, which might be due to stimulation of the development of a delta-opioid receptor subtype or activation of G-protein coupling processes. 2. We have addressed the possibility that weaning stimulates coupling of the delta-receptor by homogenate binding studies with four agonist and one antagonist radioligand in the presence of a GTP analogue and Na+ in brain tissue from weaned and non-weaned animals. 3. Saturation studies with three agonist ligands ([3H]-deltorphin I, [3H]-S-Atc-Ile(5,6)deltorphin I and [3H]-R-Atc-Ile(5,6)deltorphin II) showed higher levels of maximal binding in brains from 25-day weaned than in brains from non-weaned rats. The magnitude of the effects of GMPPNP and Na+ in decreasing this binding was ligand dependent and in each case was significantly more marked in brains from weaned animals. GMPPNP and Na+ were completely without effect on Bmax for, [3H]-S-Atc-Ile(5,6)deltorphin I and [3H]-R-Atc-Ile(5,6)deltorphin II in brains from non-weaned rats. 4. [3H]-Ile(5,6)deltorphin II and [3H]-naltrindole showed no differences in labelling between weaned and non-weaned groups and both groups responded similarly to the effects of GMPPNP and Na+ treatment. 5. GMPPNP and Na+ had small effects on binding affinity (K(D)) for some of the agonist radioligands which were similar in both weaned and non-weaned groups. 6. Weaning induced increases in binding of delta-receptors in 25-day rats can be explained in terms of the way delta-agonist radioligands recognize the receptor environment.

Role of the histidine residue at position 105 in the human alpha 5 containing GABA(A) receptor on the affinity and efficacy of benzodiazepine site ligands.

1. A histidine residue in the N-terminal extracellular region of alpha 1,2,3,5 subunits of the human GABA(A) receptor, which is replaced by an arginine in alpha 4 and alpha 6 subunits, is a major determinant for high affinity binding of classical benzodiazepine (BZ)-site ligands. The effect of mutating this histidine at position 105 in the alpha 5 subunit to an arginine (alpha 5H105R) on BZ-site pharmacology has been investigated using radioligand binding on HEK293 and L(tk-) cells and two electrode voltage clamp recording on Xenopus oocytes in which GABA(A) receptors of subtypes alpha 5, alpha 5H105R, alpha 4 and alpha 6 were co-expressed with beta 3 gamma 2s. 2. The classical BZs, diazepam and flunitrazepam (full agonists on the alpha 5 receptor) showed negligible affinity and therefore negligible efficacy on alpha 5H105R receptors. The beta-carbolines DMCM and beta CCE (inverse agonists on the alpha 5 receptor) retained some affinity but did not exhibit inverse agonist efficacy at alpha 5H105R receptors. Therefore, the alpha 5H105R mutation confers an alpha 4/alpha 6-like pharmacology to the classical BZs and beta-carbolines. 3. Ro15-4513, flumazenil, bretazenil and FG8094, which share a common imidazobenzodiazepine core structure, retained high affinity and were higher efficacy agonists on alpha 5H105R receptors than would be predicted from an alpha 4/alpha 6 pharmacological profile. This effect was antagonized by DMCM, which competes for the BZ-site and therefore is likely to be mediated via the BZ-site. 4. These data indicate that the conserved histidine residue in the alpha subunit is not only a key determinant in the affinity of BZ-site ligands on alpha 5 containing GABA(A) receptors, but also influences ligand efficacy.

Analysis of cytological changes in hepatocytes from rats dosed with 3'-methyl-4-dimethylaminoazobenzene: initial response appears to involve cytokinesis of binucleated cells.

The reduction in the ratio of tetraploid (4N + 2 X 2N) to diploid (2N) hepatocytes in the adult rat after treatment with the hepatocarcinogen 3'-methyl-4-dimethylaminoazobenzene (3'M) has been investigated. Analysis of isolated hepatocytes 18-28 days after treatment has confirmed that initially some of the 2 X 2N hepatocytes are converted into 2N cells by cytokinesis, and that there is no DNA synthesis during this process. Shortly afterwards nonpolyploidizing growth commences by proliferation of some 2N cells.

Relaxation of the mouse isolated aorta and carotid artery in response to adenosine analogues in genetically-modified mice lacking the adenosine A(2A) receptor.

The aim of this study was to characterise the receptor(s) mediating responses to adenosine and/or adenosine analogues in mouse isolated aorta and carotid artery. In addition, since mice lacking the A(2A) adenosine receptor are reported to be hypertensive, the possibility that this gene deletion or the altered phenotype results in alteration of responses mediated via adenosine analogues was investigated. This was achieved by comparing results obtained in parallel within single experiments using tissues from A(2A) knock-out animals and their wild-type littermates.In aortic rings, adenosine and 5'- N-ethylcarboxamidoadenosine (NECA) caused relaxations above 10 microM and 30 microM, respectively, which were unaffected by either 8-sulphophenyltheophylline (8-SPT, 100 microM) or A(2A) receptor knockout. 2-[ p-(2-Carbonylethyl)phenylethylamino]-5'- N-ethylcarboxamidoadenosine (CGS 21680) was virtually inactive. R- N(6)-Phenylisopropyladenosine (R-PIA) induced relaxations which were not inhibited by 8-SPT (100 microM) or altered by A(2A) receptor knockout. No A(1)-mediated contractile responses were observed in wild-type or knock-out tissues in contrast with results in mice of the same strain obtained commercially rather than from our breeding programme. In carotid artery rings NECA contracted at low concentrations (0.1-1 microM) and relaxed at higher concentrations. Curves to NECA were not different in tissues from wild-type and A(2A) receptor knock-out mice and both the contractile and relaxant phases were right-shifted by 8-SPT (100 microM) in tissues from animals of both genotype. 1,3-Dipropyl-8-cyclopentylxanthine (DPCPX, 3 nM) attenuated contractile NECA responses but did not affect relaxant responses. CGS 21680 was inactive in carotid artery rings from both wild-type and A(2A) receptor knock-out mice. In the presence of DPCPX (30 nM) to abolish contractions, R-PIA induced relaxant curves which were not different in tissues from wild-type and A(2A) knock-out mice and were not inhibited by 8-SPT (100 microM). These results confirm the absence of A(2A) or A(2B) receptors in murine aorta and suggest that relaxations to NECA in carotid artery are A(2B) receptor-mediated whilst contractions are A(1) receptor-mediated. They also indicate the presence of an antagonist-resistant site activated by R-PIA in both vascular preparations. There is no evidence for compensatory changes in responses mediated by adenosine and its analogues due to the gene deletion or the reported resulting hypertensive phenotype in either aortic or carotid arterial rings obtained from A(2A) knock-out mice.

Rapid generation of homologous internal standards and evaluation of data for quantitation of messenger RNA by competitive polymerase chain reaction.

Sensitive and quantitative measurement of messenger RNA (mRNA) is important for accurate assessment of gene expression. Conventional methods of mRNA measurement frequently lack the sensitivity required to detect mRNA expressed at low level, such as mRNA encoding receptors and intracellar signaling molecules. Thus, the extremely sensitive RT-PCR has become the method of choice for examination of gene expression. However, quantitation of mRNA by PCR is difficult because small variations in amplification efficiencies among sample tubes can lead to substantial differences in product yield, thereby rendering direct comparisons between samples invalid. Development of protocols for quantitative RT-PCR has relied on internal standards to monitor the efficiency of the RT-PCR in different reaction tubes. Technically, the two most serious limitations to routine successful application of competitive quantitative PCR is ready access to competitive internal standards and efficient methods for accurate quantitative analysis of the data. In the present manuscript, application and validation of a simple approach to generate homologous internal competitive standards and to quantitate data for rapid, accurate determination of the expression level of genes by quantitative PCR is described. Generation of the competitive standard from a previously amplified PCR product by the methods described requires only one additional primer pair, and an additional two-step reaction; it can be completed in 1-2 days. Analyzing the results of the competitive PCR reaction via phosphoimager analysis provides a simple, rapid method for accurate quantitation of results. Data presented here clearly illustrate that the methods described have been successfully applied, and that they should have wide application for competitive quantitative PCR analysis of gene expression.

Laparoscopic anatomy of the cystic artery.

Uncontrolled arterial bleeding during laparoscopic cholecystectomy is a serious problem and may increase the risk of bile duct damage. Therefore, accurate identification of the anatomy of the cystic artery is important. We reviewed the anatomy of the cystic artery and its variations as seen through the video laparoscope. A "normal" cystic artery was found in only 72% of patients. The most important laparoscopically noted variations were doubling of the cystic artery (22%) and an artery that ran inferior to the cystic duct (6%). Small branches of the cystic artery, which we suggest be named Calot's arteries, supply the cystic duct and may cause troublesome bleeding during laparoscopic dissection in the hepatobiliary triangle. A scissor dissection technique was found most useful for identifying the arterial anatomy. Careful identification of arterial anomalies should help to reduce the incidence of bile duct injuries during laparoscopic cholecystectomy.

Clinical Protocol for p53 Gene Therapy for Liver Tumors.

This chapter is intended to help other workers with the preparation of human gene therapy proposals. What follows is an abridged version of a protocol describing the use of gene replacement with p53 for liver tumors. This was submitted to the Gene Therapy Advisory Committee (GTAC) of the Department of Health (United Kingdom). This is the first trial to be approved by GTAC for gene therapy of liver tumors in humans.

p53 Plasmid Preparation and Techniques for Analysis of Gene Transfer and Expression.

Hepatocellular carcinoma (HCC) is one of the most common causes of cancer death worldwide and is especially prevalent in certain areas of Africa and Asia. The most important etiological factor is infection with the hepatitis B or C virus. Treatment is generally unsatisfactory as the majority of patients are not suitable for surgical resection and chemotherapy is not particularly effective.

Factor analysis and matrix invariance of the HRNB-C category test.

This study examined the factorial invariance of the six individual Halstead-Reitan Neuropsychological Battery for Older Children (HRNB-C) Category subtests. The test scores for two large samples of learning disabled children were factor analyzed. A three-factor solution emerged for each group with a clear pattern of variable loadings. Category subtests IV and V load on Factor 1, subtests III and VI on Factor 2, and subtests I and II on Factor 3. Variable loadings were not only of similar pattern, but also magnitude and sign for both samples. Moreover, comparison statistics indicate an excellent fit between the two factor matrices. Results support the conclusion that the HRNB-C Category Test measures more than a single underlying construct.

A low-copy number plasmid mediating beta-lactamase production by Xanthomonas maltophilia.

To delineate the mechanisms contributing to the high level of antimicrobial resistance often demonstrated by Xanthomonas maltophilia, plasmid DNA was isolated from 5 clinical isolates and analyzed. Purified plasmid DNA from a single isolate contained a 6.5 kb plasmid (pXM222) and a 5.6 kb plasmid, (pTHB). Transformation of pTHB into E. coli HB101 resulted in the expression of resistance to all penicillins tested and cefazolin.

Effects of external beam irradiation on the TRAM flap: an experimental model.

The rat model of the transverse rectus abdominis musculocutaneous (TRAM) flap was used in the present study to determine the effects of external beam radiation on myocutaneous flap histology and pathophysiology. A total of 57 adult Sprague-Dawley rats underwent a TRAM procedure. A pilot study with 17 animals was first performed to determine proper radiation dosages, and the remaining 40 rats were then used in the definitive study. In half of the definitive study group, the flaps were subjected to fractionated doses of external beam radiation, whereas the other half served as controls. Six weeks after the last radiation dose, all animals were killed and the flaps were harvested for mechanical assessment and histopathologic evaluation. All TRAM flaps survived in both groups. The irradiated and nonirradiated flaps were minimally distinguishable in viscoelastic properties, as well as by histopathologic examination. Growth of the flap in the irradiated animals was significantly diminished (48 percent average surface area increase in irradiated flaps, versus 92 percent increase in nonirradiated flaps, p < 0.05). These findings suggest that the myocutaneous flap is relatively resistant to some of the known adverse affects of radiation on living tissues.