[Morphofunctional Analysis of the Role of Epicardial Adipose Tissue in the Formation of the Obesity Paradox in Chronic Heart Failure]

Based on the available modern medical literature, the article summarizes data on the morpho-functional significance of epicardial adipose tissue (EAT) in health and heart failure, analyzes the likelihood and reliability of the formation of the obesity paradox, and also discusses its possible morpho-functional mechanisms. The authors reviewed and analyzed the consequences of the obesity paradox in the aspect of the normal EAT phenotype protectivity. The review proposed ways of further research in this direction aimed at a deep anatomical and physiological analysis and at determining the morpho-functional role of EAT in the adaptive mechanisms of myocardial trophic provision, which may be an important part of the pathogenetic connection between obesity and CHF and, therefore, can improve outcomes in such patients.

Circulating bile acids concentration is predictive of coronary artery disease in human

Synthetized by the liver and metabolized by the gut microbiota, BA are involved in metabolic liver diseases that are associated with cardiovascular disorders. Animal models of atheroma documented a powerful anti-atherosclerotic effect of bile acids (BA). This prospective study examined whether variations in circulating BA are predictive of coronary artery disease (CAD) in human. Consecutive patients undergoing coronary angiography were enrolled. Circulating and fecal BA were measured by high pressure liquid chromatography and tandem mass spectrometry. Of 406 screened patients, 80 were prospectively included and divided in two groups with (n = 45) and without (n = 35) CAD. The mean serum concentration of total BA was twice lower in patients with, versus without CAD (P = 0.005). Adjusted for gender and age, this decrease was an independent predictor of CAD. In a subgroup of 17 patients, statin therapy doubled the serum BA concentration. Decreased serum concentrations of BA were predictors of CAD in humans. A subgroup analysis showed a possible correction by statins. With respect to the anti-atherosclerotic effect of BA in animal models, and their role in human lipid metabolism, this study describe a new metabolic disturbance associated to CAD in human.

Predictors and clinical impact of thrombosis after transcatheter mitral valve implantation using balloon-expandable bioprostheses

AIMS

The aim of this study was to report the predictors and clinical impact of transcatheter heart valve (THV) thrombosis in patients undergoing transcatheter mitral valve implantation (TMVI).

METHODS AND RESULTS

We included 130 patients who consecutively underwent TMVI. Transoesophageal echocardiography (TOE) and/or computed tomography (CT) were performed in 91.7% of patients at discharge, in 73.3% at three months and in 72% beyond three months. THV thrombosis was defined as the presence of at least one thickened leaflet with restricted motion confirmed by TOE or contrast CT and classified as immediate, early, or late according to the timing of diagnosis. THV thrombosis was observed in 16 (12.3%) patients: immediate in 43.7%, early in 37.5% and late in 18.8%. Most of these thromboses were subclinical (93.7%) and non-obstructive (87.5%). No thromboembolic event occurred. After optimisation of antithrombotic treatment, THV thromboses resolved in all but one patient. Predictors were shock for immediate (p<0.001), male sex for early (p=0.045) and absence of anticoagulation for both early (p=0.018) and late (p=0.023) THV thromboses.

CONCLUSIONS

THV thrombosis is frequent after TMVI, occurs mainly within the first three months, is mostly subclinical and resolves after optimisation of antithrombotic treatment. An anticoagulation therapy for at least three months after the procedure is mandatory.

Saccharomyces boulardii CNCM I-745 Modulates the Fecal Bile Acids Metabolism During Antimicrobial Therapy in Healthy Volunteers

Saccharomyces boulardii CNCM I-745 (SB) is a probiotic yeast used to lower the incidence of antibiotic-associated Clostridium difficile (C. difficile) infection, though its mechanism of action remains unclear. Cholic acid is a primary bile acid, which triggers the germination and promotes the growth of C. difficile. The intestinal microbiota transforms primary into secondary bile acids. This study examined (1) the antimicrobial-induced alteration of fecal bile acid content, and (2) whether the concomitant administration of SB influences this transformation. This is an ancillary work from a randomized study, which revealed that SB modulates fecal microbiota dysbiosis during antibiotic treatment. Healthy subjects were randomly assigned to (1) SB only, (2) amoxicillin-clavulanate (AC), (3) SB plus AC, or (4) no treatment. We analyzed fecal concentrations of BA by high performance liquid chromatography/tandem mass spectrometry. Compared to the untreated or the SB-treated groups, AC decreased the percentage of fecal secondary BA significantly (days 3 and 7). When SB and AC were administered concomitantly, this decrease in secondary BA was no longer significant. Following treatment with AC, a significant peak of fecal CA was measured on days 3 and 7, which was prevented by the concomitant administration of SB. AC administered to healthy volunteers altered the microbial transformation of primary BA, decreased secondary BA, and increased CA. The latter was prevented by the concomitant administration of SB and AC, suggesting a potent mechanism protection conferred by SB against post-antimicrobial C. difficile infection.

Clinical Trial Registration:www.ClinicalTrials.gov, identifier NCT01473368.

The No Endosonographic Detection of Tumor (NEST) Study: a case series of pancreatic cancers missed on endoscopic ultrasonography

BACKGROUND AND STUDY AIMS

The purpose of this study was to identify possible associated factors that may have contributed to failure to detect a pancreatic neoplasm during endoscopic ultrasound (EUS) examinations by experienced endosonographers.

PATIENTS AND METHODS

A multicenter retrospective study was organized, and 20 cases of pancreatic neoplasms missed by nine experienced endosonographers were identified. Careful analysis of each case was carried out to identify the factors that might have led to the missed diagnosis on EUS.

RESULTS

Twelve patients with a missed pancreatic neoplasm had EUS features of chronic pancreatitis. Other factors that might have increased the likelihood of a false-negative EUS examination included a diffusely infiltrating carcinoma (n = 3), a prominent ventral/dorsal split (n = 2), and a recent episode (within the previous 4 weeks) of acute pancreatitis (n = 1). Five patients with a negative initial EUS underwent a follow-up EUS after 2-3 months, with a pancreatic mass being found in all cases. Three patients had a diffusely infiltrating pancreatic adenocarcinoma.

CONCLUSIONS

EUS is not a foolproof method of detecting a pancreatic neoplasm. Possible associated factors that may increase the likelihood of a false-negative EUS examination include chronic pancreatitis, a diffusely infiltrating carcinoma, a prominent ventral/dorsal split and a recent episode (< 4 weeks) of acute pancreatitis. If there is a high clinical suspicion of pancreatic neoplasm, if EUS and other imaging methods are negative, and if the patient does not undergo surgery, this study suggests that a repeat EUS after 2-3 months may be useful for detecting an occult pancreatic neoplasm.

Evaluation of metastatic celiac axis lymph nodes in patients with esophageal carcinoma: accuracy of EUS

BACKGROUND

Endosonography (EUS) is the most accurate modality for assessing depth of tumor invasion and local lymph node metastasis. However, its accuracy in the identification of metastatic (celiac axis) lymph nodes is less well defined. Our objective in this study was to determine the accuracy of Eus in detecting celiac axis lymph node metastasis in patients with esophageal carcinoma.

METHODS

Two hundred fourteen patients with esophageal carcinoma underwent preoperative EUS. Of these, 145 underwent attempted surgical resection and staging, and 4 underwent EUS-guided fine-needle aspiration of mediastinal and celiac lymph nodes. Local (mediastinal) and distant (celiac axis) lymph nodes were assessed for malignancy on the basis of four criteria (larger than 1 cm, round, homogeneous echo pattern, sharp borders). Accuracy of EUS was determined by means of correlating histopathologic findings for the resected lymph nodes or results of EUS-guided fine-needle aspiration cytologic examination.

RESULTS

Surgical exploration (n = 145) and fine-needle aspiration cytologic examination (n = 4) revealed metastatic celiac axis lymph nodes in 23 and metastatic mediastinal (local) lymph nodes in 93 of 149 patients with esophageal carcinoma. According to defined criteria for malignant lymph nodes, there were 19 true-positive and 4 falsenegative results. Sensitivity for the diagnosis of celiac lymph node metastasis with EUS was 83% with a 98% specificity. For the diagnosis of mediastinal lymph node metastasis, sensitivity was 79% and specificity was 63%. All patients with malignant celiac axis lymph nodes had local T3 (tumor breaching adventitia) or T4 (tumor invading adjacent organs) disease.

CONCLUSION

EUS is an excellent modality in the evaluation of metastatic celiac axis lymph nodes in patients with esophageal carcinoma. These findings should be used in selecting options for treatment. Sensitivity for detecting malignancy is consistent with that of prior studies, and local and regional lymph nodes and specificity is significantly higher.

What is the current role of endoscopic ultrasonography in oesophageal cancer?

Endoscopic ultrasonography is, probably, the most significant progress in gastrointestinal endoscopy of the last few years, and it is on the way to becoming the gold standard for pre-treatment staging of oesophageal carcinoma. Once computed tomography scan has ruled out distant metastases or evident local invasion, endoscopic ultrasonography plays a key role in an adjunctive evaluation and planning of treatment. The diagnostic accuracy of endoscopic ultrasonography in oesophageal cancer is excellent. Its main limitations are: poor differentiation between early mucosal and submucosal cancer, insufficient accuracy in detecting early lymph node invasion, and lack of complete tumour evaluation in cases of high-grade strictures. The role of endoscopic ultrasonography in post-treatment assessment is still limited by some artifacts. However, all these limitations will soon be overcome by some technical improvements.

HAP4, the glucose-repressed regulated subunit of the HAP transcriptional complex involved in the fermentation-respiration shift, has a functional homologue in the respiratory yeast Kluyveromyces lactis

In Saccharomyces cerevisiae, the heteromeric HAP transcription factor is necessary for optimal growth on respiratory carbon sources. One of its components, the Hap4p protein, is necessary for transcriptional activation. The same protein is also the regulatory part of the complex in response to carbon sources, as HAP4 is strongly induced during the shift from fermentative to respiratory metabolism in S. cerevisiae. We report here the characterization of a new gene from the respiratory yeast Kluyveromyces lactis, obtained by heterologous complementation of a delta hap4 S. cerevisiae mutant strain. The deduced sequence of the protein (643 amino acids) exhibits two small domains (11 and 16 amino acids respectively) highly homologous to corresponding domains of ScHap4p, while the overall similarity is rather weak. Additional experiments were performed to confirm the functional homology of this new gene with ScHAP4, which we named KIHAP4. The importance of the small highly conserved N-terminal sequence was confirmed by in vitro mutagenesis. All the mutations that interfere with the Hap4p-Hap2/3/5 interaction were localized in it. The discovery of the same regulatory protein in two metabolically distinct yeast species raises the question of its functional significance during evolution.

Spontaneous rupture of a bile duct and its endoscopic management in a patient with Caroli's syndrome

Caroli's syndrome is a condition of cystic dilation of intrahepatic bile ducts that communicate with the extrahepatic biliary tree. Patients with Caroli's syndrome are prone to develop several complications. These include bacterial cholangitis, biliary sludge, calculi, and cholangiocarcinoma. We describe an adult patient with Caroli's syndrome in whom spontaneous rupture of a bile duct developed with consequent biliary peritonitis, which was successfully managed with endoscopic stent placement.

A new system for defining endoscopic complications emphasizing the measure of importance

BACKGROUND

Currently, there are no satisfactory systems for defining, classifying, and/or scoring endoscopic complications, although it would be important for quality assurance, comparative studies, and outcomes research. Recently the term "negative outcomes" was proposed rather than "complications," and an approach that incorporates "measures of importance" was added to compare negative outcomes.

METHODS

A system was developed that defines, classifies, and grades negative outcomes with a scoring system based on measures of importance. Information was recorded on a Morbidity and Mortality (M & M) form, which was used at a monthly quality assurance (M & M) conference. Several measures of importance related to the immediate negative outcome (O) were quantified (effect of the complication on completion of the endoscopy, change in level of care, change in number of hospital days, necessity for new invasive procedures). The disability (D), defined as a residual or chronic negative outcome caused by the complication, was characterized and scored. Death (D) was also characterized, the value varying with circumstances. As a quantitative measure, an overall ODD score was used.

RESULTS

One hundred twenty-three negative outcomes were retrospectively classified using the new M & M form and the ODD score was applied for 117 complications. Complications were ranked according to the ODD score.

CONCLUSION

A system for defining, classifying, and grading negative outcomes of endoscopic procedures is proposed with a quantitative scoring system that emphasizes measures of importance. The ODD score looks at the immediate negative outcome and also the separate long-term issues of disability and death.

Flumazenil reversal of psychomotor impairment due to midazolam or diazepam for conscious sedation for upper endoscopy

BACKGROUND

Flumazenil is a competitive benzodiazepine antagonist that acts to reverse their sedative and hypnotic effects. It is indicated in the management of benzodiazepine overdose, but its role in the routine reversal of endoscopic conscious sedation has not been defined.

METHODS

Patients undergoing diagnostic upper endoscopy who received sedation with either diazepam or midazolam alone were given flumazenil 0.2 mg incrementally immediately following the procedure until awake. They were then asked to repeat three psychomotor tests measuring cognitive and motor skills, with their baseline scores compared with postprocedure scores over a 3-hour period.

RESULTS

Full psychomotor function was restored to baseline values within 30 minutes after flumazenil in 79% of patients, with no differences in the reversal of psychomotor skill impairment observed between diazepam and midazolam sedation. There was no evidence of rebound sedation seen for up to 3 hours. No significant anterograde amnesia was evident in 78% of individuals.

CONCLUSIONS

These results demonstrate that flumazenil's effects on reversing psychomotor impairment are similar when midazolam or diazepam are used for conscious sedation. However, the potential usefulness of routine flumazenil reversal of conscious sedation will require further evaluation of specific psychomotor performance skills (such as driving a car) before we lift the admonition against leaving the endoscopic suite unattended, driving a vehicle, or operating complicated machinery for several hours.

Structural and phylogenetic analysis of the MotA and MotB families of bacterial flagellar motor proteins

MotA and MotB are two well-characterized proteins in Escherichia coli which are believed to function as the proton channel and the anchor, respectively, of the motor component of the bacterial flagellum. We have identified and analysed all currently sequenced members of the MotA and MotB families. Members of these families include (1) these E. coli proteins, (2) their pmf-interacting motor homologues in other bacteria, (3) two ORFs which map downstream of the gene encoding the catabolite repression-mediating CepA protein in Bacillus species and (4) unidentified open reading frames. With one exception (the MotB protein of Rhodobactec sphaeroides), members of the MotB family exhibit a C-terminal domain that is homologous to peptidoglycan-interaction domains of numerous sequenced lipoproteins and outer membrane proteins. Multiple alignments, average hydropathy and similarity plots, and phylogenetic trees have allowed (1) identification of regions of relative conservation, (2) definition of signature sequences for these protein families and (3) determination of relative phylogenetic distances relating all members of each family. The phylogenies of these proteins do not follow those of the organisms from which they were isolated, suggesting the presence of divergent isoforms in many bacteria. Phylogenetic analyses of the peptidoglycan-interaction domains of MotB proteins indicated that, except for MotB of R. sphaeroides, these domains became associated with the MotB proteins early during evolutionary history, before members of the MotB family or members of the outer membrane protein family diverged from each other.

High-resolution chromoendoscopy for the diagnosis of diminutive colon polyps: implications for colon cancer screening

BACKGROUND & AIMS

A visual, nonbiopsy technique that could reliably determine the histology of diminutive colorectal polyps could greatly reduce the cost of colon cancer screening. This study was designed to report our experience using a high-resolution colonoscope combined with indigo carmine dye to diagnosis diminutive colorectal polyps.

METHODS

Colonoscopy using a Fujinon EC-400 HM/HL was performed in 36 patients with polyps <10mm in diameter. Polyps from the first 12 patients (phase 1) were sprayed with 10 mL of 0.2% indigo carmine dye, and a biopsy was performed or a specimen removed and submitted for histological analysis. The morphological data were used to predict polyp histology in the subsequent 24 patients (phase 2).

RESULTS

Hyperplastic polyps had a characteristic surface "pit pattern" of orderly arranged "dots" that resembled the surrounding, nonpolypoid mucosa. Adenomatous polyps had surface "grooves" or "sulci." Sensitivity and specificity of our techniques in distinguishing adenomatous from nonadenomatous colorectal polyps were 93% and 95% respectively.

CONCLUSIONS

High-resolution chromoendoscopy provides morphological detail of diminutive colorectal polyps that correlates well with polyp histology. If incorporated into colon cancer screening, these techniques may limit the need for biopsy and/or subsequent colonoscopy and ultimately decrease costs.

Phylogenetic, structural and functional analyses of the LacI-GalR family of bacterial transcription factors

Phylogenetic tree construction for 25 sequenced members of the LacI-GalR family (LGF) of transcription factors revealed that almost all branches are similar in length, radiating essentially from a single point. This observation suggests that most of these proteins arose by duplication events which occurred at a specific time in evolutionary history, and that further duplication events were rare. Analyses of the multiple alignment of the LGF proteins lead to suggestions regarding structure-function relationships and reveal that the helix-turn-helix DNA-binding motif of LGF proteins is similar in sequence to those of numerous non-homologous DNA-binding proteins.

Phylogenetic analysis of the putative phosphorylation domain in the pyruvate kinase of Bacillus stearothermophilus

All sequenced phosphoenolpyruvate synthases (PPS), pyruvate:phosphate dikinases (PPDK) and enzymes I (EI) of the phosphoenolpyruvate:sugar phosphotransferase system comprise the PEP family. Linked to the C terminus of the sequenced pyruvate kinase from Bacillus stearothermophilus (PKBst) is a domain that is homologous to the putative phosphorylation domains of PEP family enzymes. We report sequence and phylogenetic analyses that lead to the following conclusions: (1) the phosphorylation domain of PKBst was derived from a PPS, late in the evolutionary process, after the divergence of PPSs from PPDKs and EIs; (2) this domain is probably functional in phosphoryl transfer; (3) the C-terminal phosphorylation domain in PKBst probably defines a compact domain in all PEP family proteins that is linked to other domains in these proteins via flexible linkers.

Endoscopic ultrasound for staging esophageal cancer, with or without dilation, is clinically important and safe

BACKGROUND

To fully evaluate patients with esophageal cancer by endoscopic ultrasonography (EUS), the transducer must pass through the entire tumor to the cardia to scan the celiac axis. Dilation may be necessary. Published information suggests that dilation with EUS carries a sizeable risk.

METHODS

In order to assess the complication rate associated with dilation prior to EUS in patients with esophageal cancer and the clinical significance of dilation for complete EUS staging, we reviewed the records of all patients who had undergone EUS for esophageal cancer.

RESULTS

Sixty-three patients underwent EUS staging of esophageal cancer. Thirty-nine (62%) had lesions through which the EUS scope was passable (Group I). Ten (16%) patients (Group II) had lesions through which an EUS scope (diameter 13 mm) was unable to pass even after dilation. Fourteen patients (22%) had lesions that were dilated to allow passage of the EUS scope (Group III). All patients in Groups II and III had confirmation of EUS staging by CT and/or surgery. In Group II, five patients had tumors defined as T4 (50%) and five as T3 (50%). In Group III, nine (64%) had T4 tumors, four (29%) had T3, and one (7.7%) had T2. No complications were encountered in any group.

CONCLUSION

EUS, either alone or after dilation, is a safe procedure and the complete EUS examination with celiac node visualization adds prognostically significant information.

MBR1 and MBR3, two related yeast genes that can suppress the growth defect of hap2, hap3 and hap4 mutants

Two new yeast genes, named MBR1 and MBR3, were isolated as multicopy suppressors of the growth defect of a strain lacking the HAP2 transcriptional activator. Both genes when overexpressed can also suppress the growth defect of hap3 and hap4 null mutants. However, overexpression of MBR1 cannot substitute for the HAP2/3/4 complex in activation of the CYC1 gene. Nucleotide sequencing of MBR1 and MBR3 revealed that these two genes encode serine-rich, hydrophilic proteins with regions of significant homology. The functional importance of one of these conserved regions was shown by mutagenesis. Disruption of MBR1 leads to a partial growth defect on glycerol medium. Disruption of MBR3 has no major effect but the double disruptant shows a synthetic phenotype suggesting that the MBR1 and MBR3 gene products participate in common function.

Diazepam versus midazolam for colonoscopy: a prospective evaluation of predicted versus actual dosing requirements

We performed a prospective, randomized, double-blind study to evaluate the efficacy of the currently recommended low doses of midazolam for conscious sedation compared with diazepam for colonoscopy. Each agent was administered in a fixed ratio dose in combination with meperidine, and titrated incrementally to allow for adequate sedation prior to initiating and during the procedure. The currently recommended starting dose of midazolam (0.03 mg/kg) proved to be very appropriate for pre-medication. In contrast, the currently recommended starting dose of diazepam (0.10 mg/kg) proved excessive in 21% of patients (especially in those aged > 65). The low initial and incremental doses of midazolam compared favorably with diazepam in all efficacy parameters studied and exceeded diazepam in post-procedure amnesia scores (p = 0.01). Moreover, the sedative effects of midazolam at these lower doses were not lost despite long duration procedures (> 40 min). We conclude that midazolam, given in small incremental doses, in combination with meperidine, produces effective conscious sedation for colonoscopy and exceeds diazepam in its amnestic effect.