The Latest Evolution of the Medtronic CoreValve System in the Era of Transcatheter Aortic Valve Replacement: Matched Comparison of the Evolut PRO and Evolut R

Objectives

The aim of this study was to investigate the hemodynamic and clinical performance of the Evolut PRO compared with its direct predecessor, the Evolut R.

Melatonin as a Topical/Systemic Formulation for the Management of Periodontitis: A Systematic Review

Objectives: To qualitatively and quantitatively review the use of melatonin as a topical/systemic formulation for the management of periodontitis. Materials and methods: PubMed; Scopus; and Web of Science databases were searched using the MesH terms “melatonin” and “periodontitis”. Title and abstracts were screened to eliminate irrelevant and duplicate articles. The full text data of the screened articles were assessed using the selection criteria. Results: Of 176 identified articles (PubMed-66; Scopus-56; Web of Science-52; Cross-reference-2), only 12 studies qualified to be included in the systematic review. Four studies assessed the independent effect of 1% topical melatonin formulation while 8 articles assessed the adjunctive use of systemic melatonin formulation (1–10 mg) following scaling and root planing (SRP). All studies showed an improvement in periodontal parameters such as pocket depth, clinical attachment loss, periodontal disease index, community periodontal index, gingival bleeding scores, and prognostic marker levels in saliva and serum. A meta-analysis of data from 2 studies revealed that 1–2 mg (systemic) melatonin supplementation reduced pocket depth; although the difference was not statistically significant and hence cannot be interpreted or used for conclusive evidence. Risk of Bias Assessment tool (RoBANS) and Cochrane Collaboration RoB tool elicited a high risk of bias in the included studies. GRADE (recommendation assessment, development, and evaluation) inferred a weak recommendation for the use of melatonin in periodontitis management. Conclusions: Melatonin supplementation (topical and systemic) in periodontitis patients improved key periodontal parameters including pocket depth and clinical attachment loss. Clinical relevance: Melatonin could be a potential host modulatory agent for periodontitis management; although the data from the present review should be interpreted carefully due to the associated high risk of bias.     

Comparison of periodontal evaluation by cone-beam computed tomography,and clinical and intraoral radiographic examinations

Objectives

Cone-beam computed tomography (CBCT) has been widely used in many fields of dentistry. However, little is known about the accuracy of CBCT for evaluation of periodontal status. The objective of this study was to compare and correlate periodontal assessments among CBCT, clinical attachment loss (CAL) measurement, and periapical (PA)/bitewing (BW) radiography.

Methods

Eighty patients (28 males, 52 females; age range, 19–84 years) from the University of Texas School of Dentistry at Houston were evaluated retrospectively. Measurements were taken on the central incisors, canines, and first molars of the right maxilla and left mandible. CAL was extracted from periodontal charts. The radiographic distance from the cementum–enamel junction (CEJ) to the alveolar crest was measured for tooth mesial and distal sites on PA/BW and CBCT images using MiPacs software and Anatomage Invivo software, respectively. One-way ANOVA and Pearson analysis were performed for statistical analyses.

Results

The CEJ–crest distances for CBCT, PA/BW, and CAL were 2.56 ± 0.12, 2.04 ± 0.12, and 2.08 ± 0.17 mm (mean ± SD), respectively. CBCT exhibited larger values than the other two methods (p < 0.05). There were highly significant positive correlations among CBCT, PA/BW, and CAL measurements at all examined sites (p < 0.001). The Pearson correlation coefficient was higher for CBCT with CAL relative to PA/BW with CAL, but the difference was not significant (r = 0.64 and r = 0.55, respectively, p > 0.05).

Conclusions

This study validates the suitability of CBCT for periodontal assessment. Further studies are necessary to optimize the measurement methodology with CBCT.

     

Renal malformations associated with mutations of developmental genes: messages from the clinic

Renal tract malformations (RTMs) account for about 40% of children with end-stage renal failure. RTMs can be caused by mutations of genes normally active in the developing kidney and lower renal tract. Moreover, some RTMs occur in the context of multi-organ malformation syndromes. For these reasons, and because genetic testing is becoming more widely available, pediatric nephrologists should work closely with clinical geneticists to make genetic diagnoses in children with RTMs, followed by appropriate family counseling. Here we highlight families with renal cysts and diabetes, renal coloboma and Fraser syndromes, and a child with microdeletion of chromosome 19q who had a rare combination of malformations. Such diagnoses provide families with often long-sought answers to the question “why was our child born with kidney disease”. Precise genetic diagnoses will also help to define cohorts of children with RTMs for long-term clinical outcome studies.     

An antibiotic produced by an insect-pathogenic bacterium suppresses host defenses through phenoloxidase inhibition

Photorhabdus is a virulent pathogen that kills its insect host by overcoming immune responses. The bacterium also secretes a range of antibiotics to suppress the growth of other invading microorganisms. Here we show that Photorhabdus produces a small-molecule antibiotic (E)-1,3-dihydroxy-2-(isopropyl)-5-(2-phenylethenyl)benzene (ST) that also acts as an inhibitor of phenoloxidase (PO) in the insect host Manduca sexta. The Photorhabdus gene stlA encodes an enzyme that produces cinnamic acid, a key precursor for production of ST, and a mutation in stlA results in loss of ST production and PO inhibitory activity, which are both restored by genetic complementation of the mutant and also by supplying cinnamic acid. ST is produced both in vitro and in vivo in sufficient quantities to account for PO inhibition and is the only detectable solvent-extractable inhibitor. A Photorhabdus stlA- mutant is significantly less virulent, proliferates slower within the host, and provokes the formation of significantly more melanotic nodules than wild-type bacteria. Virulence of the stlA- mutant is also rescued by supplying cinnamic acid. The proximate cause of the virulence effect, however, is the inhibition of PO, because the effect of the stlA- mutation on virulence is abolished in insects in which PO has been knocked down by RNA interference (RNAi). Thus, ST has a dual function both as a PO inhibitor to counter host immune reactions and also as an antibiotic to exclude microbial competitors from the insect cadaver.     

Allene formation by gold catalyzed cross-coupling of masked carbenes and vinylidenes

Addition of a sterically demanding cyclic (alkyl)(amino)carbene (CAAC) to AuCl(SMe(2)) followed by treatment with [Et(3)Si(Tol)](+)[B(C(6)F(5))(4)](-) in toluene affords the isolable [(CAAC)Au(eta(2)-toluene)](+)[B(C(6)F(5))(4)](-) complex. This cationic Au(I) complex efficiently mediates the catalytic coupling of enamines and terminal alkynes to yield allenes and not propargyl amines as observed with other catalysts. Mono-, di-, and tri-substituted enamines can be used, as well as aryl-, alkyl-, and trimethylsilyl-substituted terminal alkynes. The reaction tolerates sterically hindered substrates and is diastereoselective. This general catalytic protocol directly couples two unsaturated carbon centers to form the three-carbon allenic core. The reaction most probably proceeds through an unprecedented "carbene/vinylidene cross-coupling."     

Labor management in a patient with von Willebrand disease

von Willebrand disease (VWD) is an inherited bleeding disorder involving a deficiency or abnormal function of a blood clotting protein called von Willebrand factor (VWF). Deficiency of VWF, therefore, shows primarily in organs with small blood vessels such as the skin, the gastrointestinal tract and the uterus. This case report describes management of a patient presenting with type II von Willebrand disease in labor. She had history of life-threatening hemorrhage from an operation for deviated nasal septum and had a risk of severe postpartum hemorrhage (PPH) within 48 hors of delivery, which was avoided by appropriate planning and timely management.