Risks of malignant lymphoma in rheumatoid arthritis patients receiving methotrexate-alone and in combination therapy compared with the general population: A study based on a Japanese medical claims database.

Objective: The risk of malignancy in patients with rheumatoid arthritis (RA) treated with methotrexate (MTX) and biological disease-modifying antirheumatic drug (bDMARD) combination therapy is unknown. This study aimed to clarify the incidence of malignancy and the recommended monitoring period in patients receiving this combination therapy.

Materials And Methods: A retrospective, observational study based on a large Japanese medical claims database was conducted between April 2013 and February 2020.

Appropriate hinge position for prevention of unstable lateral hinge fracture in open wedge high tibial osteotomy.

Aims: Open wedge high tibial osteotomy (OWHTO) for medial-compartment osteoarthritis of the knee can be complicated by intra-operative lateral hinge fracture (LHF). We aimed to establish the relationship between hinge position and fracture types, and suggest an appropriate hinge position to reduce the risk of this complication.

Patients And Methods: Consecutive patients undergoing OWHTO were evaluated on coronal multiplanar reconstruction CT images.

Closed Wedge Distal Femoral Osteotomy with a Polyaxial Locking Plate Designed for the Proximal Tibia: Minimum 5-Year Outcomes.

Since distal femoral varus osteotomy (DFO) -specific plates had not been available in Japan before 2015, we performed DFO using a plate for tibia. The purpose of this study was to elucidate the efficacy and problems associated with the non-specific plate in DFO. We used NCB-PT plates (Zimmer Inc.

Rotator cuff repair augmentation in a rat model that combines a multilayer xenograft tendon scaffold with bone marrow stromal cells.

Hypothesis: A composite of multilayer tendon slices (COMTS) seeded with bone marrow stromal cells (BMSCs) may impart mechanical and biologic augmentation effects on supraspinatus tendon repair under tension, thereby improving the healing process after surgery in rats.

Methods: Adult female Lewis rats (n = 39) underwent transection of the supraspinatus tendon and a 2-mm tendon resection at the distal end, followed by immediate repair to its bony insertion site under tension. Animals received 1 of 3 treatments at the repair site: (1) no augmentation, (2) COMTS augmentation alone, or (3) BMSC-seeded COMTS augmentation.

Crystal Structure of Antagonist Bound Human Lysophosphatidic Acid Receptor 1.

Lipid biology continues to emerge as an area of significant therapeutic interest, particularly as the result of an enhanced understanding of the wealth of signaling molecules with diverse physiological properties. This growth in knowledge is epitomized by lysophosphatidic acid (LPA), which functions through interactions with at least six cognate G protein-coupled receptors. Herein, we present three crystal structures of LPA1 in complex with antagonist tool compounds selected and designed through structural and stability analyses.

Muscle activity pattern of the shoulder external rotators differs in adduction and abduction: an analysis using positron emission tomography.

Background: The muscle activity pattern during shoulder external rotation has not been fully clarified. This study aimed to determine the activities involved in external rotation in the adducted and abducted positions using positron emission tomography (PET).

Methods: Seven healthy volunteers underwent PET examinations after performing external rotation using an elastic band at both 0° and 90° of shoulder abduction in the frontal plane.

The effect of the remplissage procedure on shoulder range of motion: a cadaveric study.

Purpose: The purpose of this in vitro biomechanical study was to assess the effects of the remplissage procedure for small- and large-sized Hill-Sachs lesions (HSLs) on shoulder range of motion (ROM) with a special interest in the apprehension position.

Methods: HSLs of 50% and 100% of the glenoid width were simulated in 7 cadaveric shoulders as small and large lesions, respectively, and the postoperative condition was reproduced by placing suture anchors on the articular surface and tying down the infraspinatus at the medial edge of the would-be lesion site. ROMs were measured in abduction, internal rotation, and external rotation with the humerus in the adducted and abducted position.

Binding modes of DL-2-haloacid dehalogenase revealed by crystallography, modeling and isotope effects studies.

Several pathways of biotic dechlorination can be found in enzymes, each characterized by different chlorine isotopic fractionation, which can thus serve as a signature of a particular mechanism. Unlike other dehalogenases, DL-2-haloacid dehalogenase, DL-DEX, converts both enantiomers of the substrate. Chlorine isotope effects for this enzyme are larger than in the case of other dehalogenases.

Differences in muscle activities during shoulder elevation in patients with symptomatic and asymptomatic rotator cuff tears: analysis by positron emission tomography.

Background: Differences in muscle activity patterns between patients with symptomatic and asymptomatic full-thickness rotator cuff tears have not yet been fully clarified. The purpose of this study was to investigate the muscle activity pattern by use of positron emission tomography (PET) in patients with symptomatic and asymptomatic rotator cuff tears.

Methods: Ten shoulders of 9 patients with full-thickness rotator cuff tears were divided into 2 groups by a numerical pain rating scale (0-10), symptomatic (≥2) and asymptomatic (0 or 1), with 5 shoulders each.

Is protecting the healing ligament beneficial after immobilization in external rotation for an initial shoulder dislocation?

Background: Immobilization in external rotation is one of the treatment options for an initial dislocation of the shoulder. However, it remains unclear how long it takes for a Bankart lesion to heal.

Hypothesis: Protection of a healing Bankart lesion from stretching would promote the healing process and decrease the recurrence rate after an initial dislocation of the shoulder.

Humeral head osteonecrosis in an adolescent amateur swimming athlete: a case report.

Osteonecrosis of the humeral head in an adolescent without clear pathogenesis has not been reported in the literature. In this case report, we present such a case of humeral head osteonecrosis in a 15-year-old adolescent. The lesion was located at the subchondral area of the medial part of the humeral head with characteristic appearances on MRI.

Reliability and validity of the Western Ontario Shoulder Instability Index (WOSI) in the Japanese population.

Background: The Western Ontario Shoulder Instability Index (WOSI) questionnaire is a disease-specific self-evaluated measurement tool used for patients with shoulder instability. The purpose of this study was to evaluate the reliability and validity of the WOSI Japanese version for the Japanese population.

Methods: The WOSI Japanese version was prepared by use of several steps including translation, back translation, and verification by the author and owner of the WOSI.

Function of the shoulder muscles during arm elevation: an assessment using positron emission tomography.

Although 2-deoxy-2-[(18)F]fluoro-D-glucose (FDG) positron emission tomography (PET) has been used for the assessment of skeletal muscle activities, its application to the shoulder muscles is only sparse. The purpose of this study was to investigate the activities of the shoulder muscles during arm elevation using PET. Six healthy volunteers performed an arm elevation exercise before and after FDG injection.

Reaction mechanism and molecular basis for selenium/sulfur discrimination of selenocysteine lyase.

Selenocysteine lyase (SCL) catalyzes the pyridoxal 5'-phosphate-dependent removal of selenium from l-selenocysteine to yield l-alanine. The enzyme is proposed to function in the recycling of the micronutrient selenium from degraded selenoproteins containing selenocysteine residue as an essential component. The enzyme exhibits strict substrate specificity toward l-selenocysteine and no activity to its cognate l-cysteine.

X-Ray crystallographic and mutational studies of fluoroacetate dehalogenase from Burkholderia sp. strain FA1.

Fluoroacetate dehalogenase catalyzes the hydrolytic defluorination of fluoroacetate to produce glycolate. The enzyme is unique in that it catalyzes the cleavage of a carbon-fluorine bond of an aliphatic compound: the bond energy of the carbon-fluorine bond is among the highest found in natural products. The enzyme also acts on chloroacetate, although much less efficiently.

Crystal structure of monofunctional histidinol phosphate phosphatase from Thermus thermophilus HB8.

Monofunctional histidinol phosphate phosphatase from Thermus thermophilus HB8, which catalyzes the dephosphorylation of l-histidinol phosphate, belongs to the PHP family, together with the PHP domain of bacterial DNA polymerase III and family X DNA polymerase. We have determined the structures of the complex with a sulfate ion, the complex with a phosphate ion, and the unliganded form at 1.6, 2.

Expression, purification and preliminary X-ray characterization of DL-2-haloacid dehalogenase from Methylobacterium sp. CPA1.

DL-2-Haloacid dehalogenase from Methylobacterium sp. CPA1 (DL-DEX Mb) is a unique enzyme that catalyzes the dehalogenation reaction without the formation of an ester intermediate. A recombinant form of DL-DEX Mb has been expressed in Escherichia coli, purified and crystallized using the hanging-drop vapour-diffusion method.

Crystal structures of Delta1-piperideine-2-carboxylate/Delta1-pyrroline-2-carboxylate reductase belonging to a new family of NAD(P)H-dependent oxidoreductases: conformational change, substrate recognition, and stereochemistry of the reaction.

Delta(1)-Piperideine-2-carboxylate/Delta(1)-pyrroline-2-carboxylate reductase from Pseudomonas syringae pv. tomato belongs to a novel sub-class in a large family of NAD(P)H-dependent oxidoreductases distinct from the conventional MDH/LDH superfamily characterized by the Rossmann fold. We have determined the structures of the following three forms of the enzyme: the unliganded form, the complex with NADPH, and the complex with NADPH and pyrrole-2-carboxylate at 1.

Crystal structures of CTP synthetase reveal ATP, UTP, and glutamine binding sites.

CTP synthetase (CTPs) catalyzes the last step in CTP biosynthesis, in which ammonia generated at the glutaminase domain reacts with the ATP-phosphorylated UTP at the synthetase domain to give CTP. Glutamine hydrolysis is active in the presence of ATP and UTP and is stimulated by the addition of GTP. We report the crystal structures of Thermus thermophilus HB8 CTPs alone, CTPs with 3SO4(2-), and CTPs with glutamine.

Super bone scan due to bone marrow metastases appearing 19 years after surgery for early gastric cancer--a case report.

A 54 year old man presenting a so-called super bone scan is reported. The patient had a past history of subtotal gastrectomy due to early gastric cancer 19 years previously. Laboratory data indicated microcytic anemia and high serum alkaline phosphatase.

Expression, purification and preliminary X-ray characterization of histidinol phosphate phosphatase.

Histidinol phosphate phosphatase (HisPPase) catalyzes the eighth step of histidine biosynthesis, in which L-histidinol phosphate undergoes dephosphorylation to give histidinol. A recombinant form of the histidinol phosphate phosphatase from Thermus thermophilus HB8 has been expressed in Escherichia coli, purified and crystallized in two crystal forms by the hanging-drop vapour-diffusion technique. Crystal form I belongs to the orthorhombic space group P2(1)2(1)2, with unit-cell parameters a = 84.

Crystal structures of glutamine:phenylpyruvate aminotransferase from Thermus thermophilus HB8: induced fit and substrate recognition.

The following three-dimensional structures of three forms of glutamine:phenylpyruvate aminotransferase from Thermus thermophilus HB8 have been determined and represent the first x-ray analysis of the enzyme: the unliganded pyridoxal 5'-phosphate form at 1.9 A resolution and two complexes with 3-phenylpropionate and alpha-keto-gamma-methylthiobutyrate at 2.35 and 2.

Crystal structures of threonine synthase from Thermus thermophilus HB8: conformational change, substrate recognition, and mechanism.

Threonine synthase, which is a PLP-dependent enzyme, catalyzes the beta,gamma-replacement reaction of l-homoserine phosphate to yield threonine and inorganic phosphate. The three-dimensional structures of the enzyme from Thermus thermophilus HB8 in its unliganded form and complexed with the substrate analogue 2-amino-5-phosphonopentanoic acid have been determined at 2.15 and 2.

Structures of argininosuccinate synthetase in enzyme-ATP substrates and enzyme-AMP product forms: stereochemistry of the catalytic reaction.

Argininosuccinate synthetase reversibly catalyzes the ATP-dependent condensation of a citrulline with an aspartate to give argininosuccinate. The structures of the enzyme from Thermus thermophilus HB8 complexed with intact ATP and substrates (citrulline and aspartate) and with AMP and product (argininosuccinate) have been determined at 2.1- and 2.