Transcatheter Tricuspid Valve Replacement for Treating Severe Tricuspid Regurgitation: Initial Experience With the NaviGate Bioprosthesis

Despite the growing evidence with emerging transcatheter tricuspid valve repair therapies, the experience with transcatheter tricuspid valve replacement remains sparse. We describe a case of severe tricuspid regurgitation in a 79-year-old patient deemed unsuitable for isolated tricuspid valve surgery, successfully treated with a 40-mm self-expandable NaviGate (NaviGate Cardiac Structures, Inc, Lake Forest, CA) valved stent via a transatrial approach, with excellent result and hemodynamic performance at 4 months.     

The Lumbar Ligamentum Flavum Does Not Have Two Layers and Is Confluent with the Interspinous Ligament: Anatomical Study with Application to Surgical and Interventional Pain Procedures

Numerous authors over the years have reported that the lumbar ligamentum flavum has two layers. Our routine cadaveric dissections raised the question whether this understanding is correct, as we always have observed only one layer. Thus, the goal of this cadaveric study was to reevaluate the layers of the ligamentum flavum. Twenty lumbar levels from five fresh-frozen cadaveric specimens were used in this study. After dissection of the lumbar spine, the ligamentum flavum and interspinous ligament were exposed. Each lumbar level was transected through the zygapophyseal joint, and hematoxylin and eosin staining, Masson's trichrome staining and Verhoeff-van Gieson staining were performed. Continuation of the interspinous ligament and ligamentum flavum were observed invariably. There was no evidence of the existence of a two-layered ligamentum flavum. The lumbar ligamentum flavum does not consist of two layers, but is confluent instead with the interspinous ligament that attaches to the zygapophyseal joints. To convey this anatomy better, we suggest describing the lumbar ligamentum flavum as a structure that consists of interlaminar and interspinous parts. Precise knowledge of the ligamentum flavum's anatomy can be of clinical value, particularly when epidural anesthesia or lumbar puncture are performed. Clin. Anat. 32:34–40, 2019. © 2019 Wiley Periodicals, Inc.     

Human gut microbiota in obesity and after gastric bypass

Recent evidence suggests that the microbial community in the human intestine may play an important role in the pathogenesis of obesity. We examined 184,094 sequences of microbial 16S rRNA genes from PCR amplicons by using the 454 pyrosequencing technology to compare the microbial community structures of 9 individuals, 3 in each of the categories of normal weight, morbidly obese, and post-gastric-bypass surgery. Phylogenetic analysis demonstrated that although the Bacteria in the human intestinal community were highly diverse, they fell mainly into 6 bacterial divisions that had distinct differences in the 3 study groups. Specifically, Firmicutes were dominant in normal-weight and obese individuals but significantly decreased in post-gastric-bypass individuals, who had a proportional increase of Gammaproteobacteria. Numbers of the H₂-producing Prevotellaceae were highly enriched in the obese individuals. Unlike the highly diverse Bacteria, the Archaea comprised mainly members of the order Methanobacteriales, which are H₂-oxidizing methanogens. Using real-time PCR, we detected significantly higher numbers of H₂-utilizing methanogenic Archaea in obese individuals than in normal-weight or post-gastric-bypass individuals. The coexistence of H₂-producing bacteria with relatively high numbers of H₂-utilizing methanogenic Archaea in the gastrointestinal tract of obese individuals leads to the hypothesis that interspecies H₂ transfer between bacterial and archaeal species is an important mechanism for increasing energy uptake by the human large intestine in obese persons. The large bacterial population shift seen in the post-gastric-bypass individuals may reflect the double impact of the gut alteration caused by the surgical procedure and the consequent changes in food ingestion and digestion.     

Anatomo‐functional organization of the ventral primary motor and premotor cortex in the macaque monkey

The ventral agranular frontal cortex of the macaque monkey is formed by a mosaic of anatomically distinct areas. Although each area has been explored by several neurophysiological studies, most of them focused on small sectors of single areas, thus leaving to be clarified which is the general anatomo‐functional organization of this wide region. To fill this gap, we studied the ventral convexity of the frontal cortex in two macaque monkeys (Macaca nemestrina) using intracortical microstimulation and extracellular recording. Functional data were then matched with the cytoarchitectonic parcellation of the recorded region. The results demonstrated the existence of a dorso‐ventral functional border, encompassing the anatomical boundary between areas F4 and F1, and a rostro‐caudal anatomo‐functional border between areas F5 and F4. The ventral subdivision of areas F4 and F1 was highly electrically excitable, represented simple mouth movements and lacked visual properties; in contrast, their dorsal counterpart showed a higher stimulation threshold, represented forelimb and mouth motor acts and hosted different types of visual properties. The data also showed that area F5 was scarcely excitable, and displayed various motor specificity (e.g. for the type of grip) and complex visual (i.e. mirror responses) properties. Overall, the posterior areas F4 and F1 appear to be involved in organizing and controlling goal‐directed mouth motor acts and simple movements within different parts of the external (dorsal sector) and internal (ventral sector) space, whereas area F5 code motor acts at a more abstract level, thus enabling the emergence of higher order socio‐cognitive functions.     

Long-term effects of ursodeoxycholic acid in primary biliary cirrhosis: results of a double-blind controlled multicentric trial. UDCA-Cooperative Group from the Spanish Association for the Study of the Liver

BACKGROUND/AIM: The aim of this study was to assess the efficacy of ursodeoxycholic acid (UDCA) for primary biliary cirrhosis in a randomized, double-blind placebo-controlled trial. METHODS: Consecutive patients (n=192) were randomized to receive 14-16 mg UDCA/kg/day or placebo. Patients underwent a complete history, physical examination, liver chemistries, immunological determinations and liver biopsy at entry and at the end of the trial, which lasted for at least 2 years. Patients were seen every 3 months and the median follow-up was 3.4 years (range 0.3 to 6.1 years). RESULTS: Patients receiving UDCA (99) or placebo (93) were comparable with regard to age, sex, biochemical parameters and liver histology. UDCA treatment was associated with decreases in alkaline phosphatase, gammaglutamyl transferase, alanine aminotransferase, and cholesterol levels, effects which were conspicuous after 3 months of treatment and remained similar during the follow-up. During the study 31 patients (10 receiving UDCA and 21 placebo) discontinued the trial because of noncompliance (n=11), voluntary withdrawal (n=19) or adverse effects (n=1). Treatment failure (death or liver transplantation) was observed in 17 patients receiving UDCA and in 11 patients receiving placebo. Times to death or liver transplantation and to clinical complications were not significantly different in patients receiving UDCA or placebo. Histological analysis indicates that UDCA improved portal inflammation and prevented histological stage progression. By contrast, histological stage as well as ductular proliferation and ductopenia progressed in patients receiving placebo. CONCLUSIONS: Although UDCA treatment did not significantly affect time to death or liver transplantation and to clinical complications, the effects on both cholestasis and liver histology suggest that UDCA is safe and may be useful for preventing the progression of primary biliary cirrhosis.