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Enantioselective C−H amination at a benzylic methylene is a vital disconnection towards chiral benzylamines. Here we disclose that butyric and valeric acid‐derived tertiary amides can undergo highly enantioselective benzylic amination using an achiral anionic Rh complex that is ion‐paired with a Cinchona alkaloid‐derived chiral cation. A broad scope of compounds can be aminated encompassing numerous arene substitutions, amides, and two different chain lengths. Excellent tolerance of ortho substituents was observed, which has not been achieved before in asymmetric intermolecular C−H amination with Rh. We speculate that the tertiary amide group of the substrate engages in hydrogen bonding interactions directly with the chiral cation, enabling a high level of organisation at the transition state for C−H amination. This is in contrast with our previous work where a substrate bearing a hydrogen bond donor was required. Control experiments led to the discovery that methyl ethers also function as proficient directing groups under the optimised conditions, potentially also acting as hydrogen bond acceptors. This finding has the promise to dramatically expand the applicability of our ion‐paired chiral catalysts. [ABSTRACT FROM AUTHOR]

Background: Transfusional iron overload causes significant morbidity and mortality in sickle cell disease (SCD). Nevertheless, red blood cell transfusions continue to be essential in its management. This study describes the transfusion patterns among SCD hospitalizations. Methods: Hospitalizations for SCD in the 2017–2018 Nationwide Readmissions Database were divided into two groups based on whether they received transfusions. Descriptive analysis was performed to compare their demographics and complications. Multivariable logistic regression was performed to determine the factors associated with transfusions. Results: Out of 109,783 hospitalizations, 28,300 were transfused, and 81,483 were not transfused. Females and older individuals were higher in the transfused category than the non-transfused category (59.49% vs. 53.52% and 28.86% vs. 21.27%, respectively; p < 0.001 for both). The wealthiest population was more likely to be in the transfused category (11.27% vs. 8.34%; p < 0.001). Admissions to teaching hospitals, large metropolitan hospitals, and highest-volume hospitals were higher in the non-transfused category vs. transfused category (79.89% vs. 72.17%; p < 0.001, 69.26% vs. 65.35%; p 0.003 and 74.71% vs. 63.51%; p < 0.001, respectively). Most admissions were transfused once, with three or more transfusions being given more in the non-teaching hospitals than the teaching hospitals (1.27% vs. 0.41%; p 0.01). Furthermore, a higher proportion of early transfusions occurred in the non-teaching hospitals (65.6% vs. 57.82% for admission days 1 and 2; p < 0.001). Admission to a teaching hospital was associated with lower blood transfusion odds than a non-teaching hospital. Conclusion: A quarter of admissions for SCD receive a blood transfusion. In addition to performing more frequent and early transfusions, the odds of being transfused are higher in non-teaching hospitals. [ABSTRACT FROM AUTHOR]

Pain after thoracotomy is one of the most severe pains after surgery. Respiratory muscle splinting due to poor control of post-operative pain may lead to respiratory complications and delayed recovery. In studies addition of dexmedetomidine or fentanyl to local anaesthetics showed enhanced quality of anaesthesia, reduced post-operative analgesic requirement and improved quality and duration of sensory neural blockade. But there are very few studies comparing dexmedetomidine and fentanyl as an adjuvant to ropivacaine in paravertebral block for post thoracotomy analgesia. 80 patients scheduled to undergo elective thoracotomy were randomly divided into two groups. Group A patients received infusion of 0.2% ropivacaine + 2µg/ml(microgram/millilitre) fentanyl @ 0.1ml/kg/h(millilitre/kilogram/hour) and Group B patients received infusion of 0.2% ropivacaine + 1µg/ml dexmedetomidine @ 0.1ml/kg/h in continuous paravertebral block. The patients had visual analogue scale(VAS) at rest between 1-3 in fentanyl group and 1-2 in dexmedetomidine group.(p value >0.05) The mean VAS score for the severity of pain at coughing was between 2-3 in fentanyl group and 1-2.5 in dexmedetomidine group and the difference is statistically significant.(p value <0.05) 12 patients in fentanyl group received rescue analgesic compared to 4 patients in dexmedetomidine group.(p value <0.05) Total fentanyl consumption was more in fentanyl group compared to dexmedetomidine group.(p value >0.05) There was no difference in incidence of side effects in both groups.(p value >0.05) Dexmedetomidine as an adjuvant to ropivacaine provided better post-operative analgesia during coughing and significantly reduced the requirement of rescue analgesic in comparison to fentanyl group without any significant adverse effects. [ABSTRACT FROM AUTHOR]

Background: The incidence of nausea and vomiting following laparoscopic cholecystectomy is very high. 5-hydroxytryptamine receptor antagonists are drug of choice for prevention of post-operative nausea and vomiting (PONV) because of their good efficacy and very few side effects in comparison to other antiemetics. Aims and Objectives: This study was undertaken to compare the efficacy and safety of intravenous ramosetron 0.3 mg and ondansetron 8 mg for prevention of PONV in patients undergoing laparoscopic cholecystectomy under general anesthesia. Materials and Methods: One hundred patients between 18 and 70 years of age with American Society of Anesthesiology Grade I and II scheduled for elective laparoscopic cholecystectomy were randomly divided into two groups of 50 patients each. Group A patients were given injection ondansetron 8 mg and Group B patients were given injection ramosetron 0.3 mg approximately 5 min just before the induction of general anesthesia. Results: Difference in Nausea, vomiting/retching, and PONV score assessed at 4, 8, 12, and 24 h interval postoperatively in both groups was found to be statistically insignificant (P>0.05). The severity of nausea was assessed by visual analogue scale at various time intervals and use of rescue antiemetics in both the groups were found statistically insignificant. Incidence of side effects was also comparable in both the groups. Conclusion: Ramosetron and ondansetron are equally effective for prevention of PONV in patients who underwent elective laparoscopic cholecystectomy under general anesthesia when used prophylactically. Both drugs are safe and have low incidence of side effects. [ABSTRACT FROM AUTHOR]

Abdominal pregnancy is a rare form of ectopic pregnancy where implantation of fertilised ovum occurs in the abdominal cavity. If diagnosed late maternal and foetal mortality is very high. The major cause of death in abdominal pregnancy is haemorrhage. The case report is about a 31-year-old gravida two with 36 weeks of gestation period with Intrauterine Foetal Death (IUFD) and celiac disease. Celiac disease is a chronic malabsorptive disease of the small intestine occurring due to hypersensitivity to gluten ingestion. Due to chronic malabsorption, the patient presented with calcium deficiency. She also had lesions of dermatitis herpetiformis over the whole body sparing only the face. It is a rare case of advanced abdominal pregnancy with the IUFD, with celiac disease. The patient was managed successfully under general anaesthesia with preparedness for difficult airway management, securing wide bore peripheral cannulas, central venous cannulation and invasive blood pressure monitoring. Massive haemorrhage intraoperatively was managed with crystalloids, colloids, blood products and tranexamic acid. The intraoperative period was uneventful. The patient was extubated at the end of the surgery, and followed-up in a high dependency unit. [ABSTRACT FROM AUTHOR]

Carotid cavernous fistula (CCF) is a specific type of dural arteriovenous (AV) fistula characterized by abnormal AV shunting within the cavernous sinus. The authors presented in this article a case of a 17-year-old young male patient who encountered a road traffic accident while driving a car, with a history of flipping of cars multiple times. The patient was unconscious with symmetrical bilateral (B/L) pupils and with Glasgow coma scale (GCS) score of 3. There was no history of seizures or vomiting. [ABSTRACT FROM AUTHOR]

Selective Csp2 –Csp2 couplings are powerful strategies for the rapid and programmable construction of bi‐ or multiaryls. To this end, the next frontier of synthetic modularity will likely arise from harnessing the coupling space that is orthogonal to the powerful Pd‐catalyzed coupling regime. This report details the realization of this concept and presents the fully selective arylation of aryl germanes (which are inert under Pd0/PdII catalysis) in the presence of the valuable functionalities C−BPin, C−SiMe3, C−I, C−Br, C−Cl, which in turn offer versatile opportunities for diversification. The protocol makes use of visible light activation combined with gold catalysis, which facilitates the selective coupling of C−Ge with aryl diazonium salts. Contrary to previous light‐/gold‐catalyzed couplings of Ar–N2+, which were specialized in Ar–N2+ scope, we present conditions to efficiently couple electron‐rich, electron‐poor, heterocyclic and sterically hindered aryl diazonium salts. Our computational data suggest that while electron‐poor Ar–N2+ salts are readily activated by gold under blue‐light irradiation, there is a competing dissociative deactivation pathway for excited electron‐rich Ar–N2+, which requires an alternative photo‐redox approach to enable productive couplings. [ABSTRACT FROM AUTHOR]

Background: To improve the speed and efficiency of root canal therapy, stainless steel instruments have been used in a variety of preparation techniques, in an attempt to produce the appropriate canal shape. However, studies have shown that procedural incidents occur commonly, producing aberrations such as formation of hourglass-shaped canals, zips, elbows and canal transportation. Nickel-Titanium (NiTi) rotary instruments are thought to reduce such aberrations. Hence; we undertook the present study to assess and compare the efficacy of engine-driven method (Ni Ti Rotary) and conventional manual methods with stainless steel K-files in performing root canal therapy in permanent molars.Materials & methods: The present study included assessment of efficacy of engine-driven method (Ni Ti Rotary) and conventional manual methods with stainless steel Kfiles in performing root canal therapy in permanent molars. 50 extracted teeth were randomly divided into two study groups as follows: Group I: Teeth in which Conventional stainless steel instruments were used, Group II: Teeth in which NiTi rotary instruments were used. Root canal therapy was performed in both the study groups by same experienced and endodontist. All the results were analysed by SPSS software. Results: Time of preparation in teeth of group I and group II was 9.36 and 14.62 minute respectively. Significant results were obtained while comparing the mean preparation time in both the study groups. Conclusion: Rotary instruments are less time consuming and increase the efficacy of the operator in performing root canal therapy. [ABSTRACT FROM AUTHOR]

Severe orthodontic problems that neither growth modification nor camoulage offers a solution, orthognathic surgery is the only possible treatment. Surgery and Orthodontics in a combined approach achieves good overall results. A case report of an adult individual with Class III malocclusion having mandibular excess treated with bilateral sagittal split osteotomy technique for the correction of skeletal, dental and soft tissue discrepancy is herewith presented. Combined surgical-orthodontic approach helped the patient to improve the self confidence level. [ABSTRACT FROM AUTHOR]

The occurrence of class III malocclusion is believed to be hereditary although the environmental factors such as habits like mouth breathing may play a role. The prevalence of class III malocclusion varies among different ethnic groups. Individuals with class III malocclusion may have combinations of skeletal and dento alveolar components. The present case report shows class III malocclusion in two siblings who were treated with the protraction face mask, during the mixed dentition [ABSTRACT FROM AUTHOR]

This case report describes the management of a root fractured maxillary left central incisor and a crown fractured maxillary right central incisor using orthodontic extrusion . A procedure was designed to manage this case using orthodontic extrusion to move the fracture line above the alveolar bone and a surgical recontouring of the altered gingival margin. The mobile segments were splinted using fixed lingual retainers. The treatment resulted in good esthetic and secured periodontal health. The case report describes a multi disciplinary approach with a predictable option to save a tooth. [ABSTRACT FROM AUTHOR]

Trauma to anterior teeth is common and requires accurate diagnosis and thorough treatment planning, the labial inclination of the maxillary incisors make them more prone to injuries. Interdisciplinary treatment approach is important for esthetic and functional rehabilitation of avulsed anterior teeth. This report addresses the fundamental considerations related to replacement of avulsed maxillary central incisors by team approach [ABSTRACT FROM AUTHOR]

The article describes a miniscrew-anchored segmental utility arch which can be used to achieve incisor intrusion without using reciprocal forces.

The regioselective conversion of C-H bonds into C-Si bonds is extremely important owing to the natural abundance and non-toxicity of silicon. Classical silylation reactions often suffer from poor functional group compatibility, low atom economy, and insufficient regioselectivity. Herein, we disclose a template-assisted method for the regioselective para silylation of toluene derivatives. A new template was designed, and the origin of selectivity was analyzed experimentally and computationally. An interesting substrate-solvent hydrogen-bonding interaction was observed. Kinetic, spectroscopic, and computational studies shed light on the reaction mechanism. The synthetic significance of this strategy was highlighted by the generation of a precursor of a potential lipophilic bioisostere of γ-aminobutyric acid (GABA), various late-stage diversifications, and by mimicking enzymatic transformations., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)