Probing Ferryl Reactivity in a Nonheme Iron Oxygenase Using an Expanded Genetic Code.

The ability to introduce noncanonical amino acids as axial ligands in heme enzymes has provided a powerful experimental tool for studying the structure and reactivity of their Fe=O ("ferryl") intermediates. Here, we show that a similar approach can be used to perturb the conserved Fe coordination environment of 2-oxoglutarate (2OG) dependent oxygenases, a versatile class of enzymes that employ highly-reactive ferryl intermediates to mediate challenging C-H functionalizations. Replacement of one of the cis-disposed histidine ligands in the oxygenase VioC with a less electron donating -methyl-histidine (MeHis) preserves both catalytic function and reaction selectivity.

An efficient pyrrolysyl-tRNA synthetase for economical production of MeHis-containing enzymes.

Genetic code expansion has emerged as a powerful tool in enzyme design and engineering, providing new insights into sophisticated catalytic mechanisms and enabling the development of enzymes with new catalytic functions. In this regard, the non-canonical histidine analogue -methylhistidine (MeHis) has proven especially versatile due to its ability to serve as a metal coordinating ligand or a catalytic nucleophile with a similar mode of reactivity to small molecule catalysts such as 4-dimethylaminopyridine (DMAP). Here we report the development of a highly efficient aminoacyl tRNA synthetase (G1PylRS) for encoding MeHis into proteins, by transplanting five known active site mutations from (PylRS) into the single domain PylRS from ISO4-G1.

Engineering mutually orthogonal PylRS/tRNA pairs for dual encoding of functional histidine analogues.

The availability of an expanded genetic code opens exciting new opportunities in enzyme design and engineering. In this regard histidine analogues have proven particularly versatile, serving as ligands to augment metalloenzyme function and as catalytic nucleophiles in designed enzymes. The ability to genetically encode multiple functional residues could greatly expand the range of chemistry accessible within enzyme active sites.

Analysis of histidine-tagged recombinant proteins from nickel and copper coated surfaces by direct electrospray ionization and desorption electrospray ionization mass spectrometry.

Rationale: Purification of recombinant proteins is a necessary step for functional or structural studies and other applications. Immobilized metal affinity chromatography is a common recombinant protein purification method. Mass spectrometry (MS) allows for confirmation of identity of expressed proteins and unambiguous detection of enzymatic substrates and reaction products.

Engineering enzyme activity using an expanded amino acid alphabet.

Enzyme design and engineering strategies are typically constrained by the limited size of nature's genetic alphabet, comprised of only 20 canonical amino acids. In recent years, site-selective incorporation of non-canonical amino acids (ncAAs) via an expanded genetic code has emerged as a powerful means of inserting new functional components into proteins, with hundreds of structurally diverse ncAAs now available. Here, we highlight how the emergence of an expanded repertoire of amino acids has opened new avenues in enzyme design and engineering.

Characterization of imine reductases in reductive amination for the exploration of structure-activity relationships.

Imine reductases (IREDs) have shown great potential as catalysts for the asymmetric synthesis of industrially relevant chiral amines, but a limited understanding of sequence activity relationships makes rational engineering challenging. Here, we describe the characterization of 80 putative and 15 previously described IREDs across 10 different transformations and confirm that reductive amination catalysis is not limited to any particular subgroup or sequence motif. Furthermore, we have identified another dehydrogenase subgroup with chemoselectivity for imine reduction.

Gastroenteritis outbreaks on cruise ships: are sanitation inspection scores a true index of risk?

Background: The utility of cruise ship sanitation scores as indicators of future gastroenteritis outbreak was investigated by means of a 5-year review of inspection scores and outbreaks of gastroenteritis as reported under the Vessel Sanitation Programme of the United States Public Health Centers for Disease Control.

Materials And Methods: Between 2012 and 2017 a total of 1197 inspections were published online, with a mean score of 95.7 out of 100.

Effects of response preference on resistance to change.

Treatments based on differential reinforcement of alternative behavior, such as functional communication training, are widely used. Research regarding the maintenance of related treatment effects is limited. Nevin and Wacker (2013) provided a conceptual framework, rooted in behavioral momentum theory, for the study of treatment maintenance that addressed two components: (a) reemergence of problem behavior, and (b) continued expression of appropriate behavior.

Cystic Fibrosis & disorders of the large intestine: DIOS, constipation, and colorectal cancer.

Since 1966 when the Cystic Fibrosis Foundation Patient Registry (CFFPR) was founded, clinicians have witnessed significant advances in both the quality and quantity of life for patients living with Cystic Fibrosis (CF). As patients with CF live longer and fuller lives, increasing encumbrances from gastrointestinal manifestations of CF will be observed. This article serves to discuss "below the diaphragm" concerns involving the large intestine (Distal Intestinal Obstruction Syndrome, Constipation, and Colorectal Cancer).

Three-dimensional segmentation of breast masses from digital breast tomosynthesis images.

Assessment of three-dimensional (3-D) morphology and volume of breast masses is important for cancer diagnosis, staging, and treatment but cannot be derived from conventional mammography. Digital breast tomosynthesis (DBT) provides data from which 3-D mass segmentation could be obtained. Our method combined Gaussian mixture models based on intensity and a texture measure indicative of in-focus structure, gray-level variance.

Preoperative implant selection for unilateral breast reconstruction using 3D imaging with the Microsoft Kinect sensor.

Aims: This study aimed to investigate whether breast volume measured preoperatively using a Kinect 3D sensor could be used to determine the most appropriate implant size for reconstruction.

Methods: Ten patients underwent 3D imaging before and after unilateral implant-based reconstruction. Imaging used seven configurations, varying patient pose and Kinect location, which were compared regarding suitability for volume measurement.

Analysis of facial morphology of UK and US general election candidates: Does the 'power face' exist?

Aims: To determine the frequency of recognised morphologic facial phenotypes among the UK and US election candidates and to assess whether there is a relationship between facial morphology and success in general elections.

Methods: Facial morphology analysis of prime ministerial and presidential candidates in the UK and US elections was performed. Direct facial measurements were made from frontal images and facial morphological indices calculated for all candidates.

Evaluation of Kinect 3D Sensor for Healthcare Imaging.

Microsoft Kinect is a three-dimensional (3D) sensor originally designed for gaming that has received growing interest as a cost-effective and safe device for healthcare imaging. Recent applications of Kinect in health monitoring, screening, rehabilitation, assistance systems, and intervention support are reviewed here. The suitability of available technologies for healthcare imaging applications is assessed.

Role of Interaction and Nucleoside Diphosphate Kinase B in Regulation of the Cystic Fibrosis Transmembrane Conductance Regulator Function by cAMP-Dependent Protein Kinase A.

Cystic fibrosis results from mutations in the cystic fibrosis transmembrane conductance regulator (CFTR), a cAMP-dependent protein kinase A (PKA) and ATP-regulated chloride channel. Here, we demonstrate that nucleoside diphosphate kinase B (NDPK-B, NM23-H2) forms a functional complex with CFTR. In airway epithelia forskolin/IBMX significantly increases NDPK-B co-localisation with CFTR whereas PKA inhibitors attenuate complex formation.

Medical emergency announcements on cruise ships: an audit of outcome.

Background: Public address announcements are an effective way of alerting staff on cruise ships to life -threatening medical emergencies on-board, but should only be used when truly necessary. An audit to investigate the outcome following this method of activating the medical emergency response team (MERT) suggested system flaws. A new elementary first aid training programme for the crew was then developed, emphasising patient assessment and the correct determination of appropriate levels of response.

ESPGHAN and NASPGHAN Report on the Assessment of Exocrine Pancreatic Function and Pancreatitis in Children.

The purpose of this clinical report is to discuss several recent advances in assessing exocrine pancreatic insufficiency (EPI) and pancreatitis in children, to review the array of pancreatic function tests, to provide an update on the inherited causes of EPI, with special emphasis on newly available genetic testing, and to review newer methods for evaluating pancreatitis.

Effects of maxillomandibular advancement on systemic blood pressure in patients with obstructive sleep apnoea.

Obstructive sleep apnoea (OSA) is associated with resistant hypertension. We investigated to what extent maxillomandibular advancement affected a patient's blood pressure postoperatively. We retrospectively analysed consecutive patients who had Bimaxillary advancement for OSA at our hospital following referral from the local sleep clinic.

Does a patient's Mallampati score predict outcome after maxillomandibular advancement for obstructive sleep apnoea?

The Mallampati airway classification has been used to estimate the success of uvulopalatopharyngoplasty in patients with obstructive sleep apnoea (OSA) but its predictive value in maxillomandibular advancement has not been proved. We aimed to explore the association between preoperative Mallampati scores and surgical outcome after bimaxillary advancement for OSA. We retrospectively analysed data on 50 patients who had maxillofacial operations for OSA at our hospital and stratified them into two groups based on Mallampati scores: high (class III/IV) and low (class I/II).

How often does the operating list follow the planned order? An analysis of elective maxillofacial operating lists.

Objectives: The authors explored consistency of the observed running order in operating sequence compared with prior scheduled listing. We analysed potential variables felt to be predictive in the chances of a patient having their procedure as previously scheduled.

Methods: Data were retrospectively collected for a consecutive group of patients who underwent elective maxillofacial procedures over a four week period.

Equine-associated maxillofacial injuries: retrospective 5-year analysis.

We explored the relation between the causes of facial injuries in equestrians and the presence or absence of associated injuries. Over a 5-year period we retrospectively reviewed all patients who presented to the John Hunter Hospital, New South Wales, with facial injuries that had resulted from activity with horses. We analysed the rates of hard and soft tissue injuries, and of associated injuries by sex and mechanism.

The influence of measurement location on reliability of quantitative nailfold videocapillaroscopy in patients with SSc.

Objectives: Nailfold videocapillaroscopy is being increasingly used as a marker of SSc-related microvascular disease, including in response to treatment. However, it requires further validation. Our aim was to assess the inter-observer, intra-observer and test-retest variability of semi-automated measurement of capillary features as well as of a manual density measurement.

Doctors recognized by the British honours systems: a retrospective analysis of the last decade.

Objectives: The British honours system is one of the oldest in the world rewarding individuals, including those of the medical profession. The authors were interested to see if any particular specialty was honoured to a greater extent. We aimed to establish the number of those honoured, the duration of clinical practice involved, as well as additional factors.

Bilateral breast reduction surgery in elderly women--a retrospective review of outcomes.

Background: Breast reduction surgery is successful in improving symptoms associated with breast hypertrophy. We sought to substantiate this in the elderly patient and ascertain how they regarded the outcome.

Methods: The WHO defines elderly as 60 and over.

Functional splinting of upper limb injuries with gauze-based topical negative pressure wound therapy.

Complex hand injuries can be difficult to dress effectively and achieve adequate splintage of the hand in a functional position. During the past 7 years, we have had a great deal of success with topical negative-pressure dressings in the management of complex blast-related extremity war injuries. We have more recently changed to using a gauze-based system and have found this particularly useful in dressing complex hand injuries.

Specificity: A Graph-Based Estimator of Divergence.

In statistical modeling, there are various techniques used to build models from training data. Quantitative comparison of modeling techniques requires a method for evaluating the quality of the fit between the model probability density function (pdf) and the training data. One graph-based measure that has been used for this purpose is the specificity.