Masashi Machii

Irxl1 mutant mice show reduced tendon differentiation and no patterning defects in musculoskeletal system development.

Irxl1 (Iroquois‐related homeobox like‐1) is a newly identified three amino‐acid loop extension (TALE) homeobox gene, which is expressed in various mesoderm‐derived tissues, particularly in the progenitors of the musculoskeletal system. To analyze the roles of Irxl1 during embryonic development, we generated mice carrying a null allele of Irxl1. Mice homozygous for the targeted allele were viable, fertile, and showed reduced tendon differentiation. Skeletal morphology and skeletal muscle weight in Irxl1‐knockout mice appeared normal. Expression patterns of several marker genes for cartilage, tendon, and muscle progenitors in homozygous mutant embryos were unchanged. These results suggest that Irxl1 is required for the tendon differentiation but dispensable for the patterning of the musculoskeletal system in development. genesis, 2011.

Distribution of late gadolinium enhancement in end-stage hypertrophic cardiomyopathy and dilated cardiomyopathy: differential diagnosis and prediction of cardiac outcome.

BACKGROUND The prognostic implications of late gadolinium enhancement (LGE) have been evaluated in ischemic and non-ischemic cardiomyopathies. The present study analyzed LGE distribution in patients with end-stage hypertrophic cardiomyopathy (ES-HCM) and with dilated cardiomyopathy (DCM), and tried to identify high risk patients in DCM. METHODS Eleven patients with ES-HCM and 72 with DCM underwent cine- and LGE-cardiac magnetic resonance and ultrasound cardiography. The patient outcome was analyzed retrospectively for 5years of follow-up. RESULTS LGE distributed mainly in the inter-ventricular septum, but spread more diffusely into other left ventricular segments in patients with ES-HCM and in a certain part of patients with DCM. Thus, patients with DCM can be divided into three groups according to LGE distribution; no LGE (n=24), localized LGE (localized at septum, n=36), and extensive LGE (spread into other segments, n=12). Reverse remodeling occurred after treatment in patients with no LGE and with localized LGE, but did not in patients with extensive LGE and with ES-HCM. The event-free survival rate for composite outcome (cardiac death, hospitalization for decompensated heart failure or ventricular arrhythmias) was lowest in patients with extensive LGE (92%, 74% and 42% in no LGE, localized LGE, and extensive LGE, p=0.02 vs. no LGE), and was comparable to that in patients with ES-HCM (42%). CONCLUSIONS In DCM, patients with extensive LGE showed no functional recovery and the lowest event-free survival rate that were comparable to patients with ES-HCM. The analysis of LGE distribution may be valuable to predict reverse remodeling and to identify high-risk patients.

Ultrasound analysis of the relationship between right internal jugular vein and common carotid artery in the left head-rotation and head-flexion position

Common carotid artery (CCA) injury is a serious complication of internal jugular vein (IJV) cannulation. To minimize unintentional CCA puncture, the anatomic relationship between the IJV and the CCA and the size of IJV were compared under different head positions. Ultrasound analyses of the IJV and the CCA were performed in 103 consecutive patients. Overlapping angle (OA), real puncture angle (RPA) and diameter of IJV (DIJV) were evaluated with 30° and 60° left rotation and with 30° left flexion. When the head position was changed from 30° left rotation to 60° left rotation, OA increased significantly from 6.5° ± 7.7° to 14.5° ± 7.4° at the cricoid cartilage level (Cricoid-level) and from 14.4° ± 8.4° to 20.6° ± 6.9° at the middle triangle level (Triangle-level), whereas RPA decreased significantly at these levels (from 49.7° ± 11.9° to 43.5° ± 13.1° and from 51.1° ± 14.4° to 44.3° ± 13.9°, respectively; P < 0.01 for both). When the head position was changed from 30° left rotation to 30° left flexion, neither OA nor RPA significantly changed (OA: 6.3° ± 6.1° and 15.0° ± 7.2°, RPA: 48.5° ± 12.4° and 51.8° ± 13.6°, P not significant vs 30° left rotation). There was no difference in DIJV when comparing 30° left rotation and 30° left flexion, although DIJV was largest at 60° left rotation. RPA positively correlated with age, and DIJV positively correlated with body mass index. In conclusion, excessive left rotation should be avoided to minimize the probability of unintentional CCA puncture during IJV cannulation. When 30° left rotation is not feasible, the head-flexion position should be utilized.

Recent changes in blood pressure levels, hypertension prevalence and treatment rates, and the rate of reaching target blood pressure in the elderly

Abstract Antihypertensive treatment has beneficial effects in the elderly. Surveying the situation of blood pressure in the elderly is quite important for planning strategies to manage elderly hypertensives. The aim of the present study was to investigate changes in blood pressure in the elderly over the past 15 years. As part of a physical check-up program between 2001 and 2015, 29,363 elderly participants (≥65 years of age) attended and were enrolled in the present study. The characteristics of the participants in each year were analyzed cross-sectionally and the results were compared over the 15 years. Changes in blood pressure, hypertension prevalence, and treatment rates, and the rate of reaching target blood pressure in the elderly were investigated. The prevalence of hypertension during the study period increased with increasing participant age. However, both the treatment rate and the rate of reaching target blood pressure in treated subjects improved. The blood pressure of treated hypertensive elderly subjects decreased from 146.1/83.0 to 130.6/75.4 mm Hg, and the reduction was most evident after revision of Japanese Society of Hypertension guidelines regarding target blood pressure in elderly hypertensives. Blood pressure in the entire cohort of elderly subjects decreased from 133.8/78.4 mm Hg in 2001 to 127.9/74.6 mm Hg in 2015. Blood pressure in elderly subjects had decreased over the 15-year study period primarily due to reductions in blood pressure in elderly hypertensive patients on medication. Guidelines for the treatment of hypertension have had a beneficial effect on the management of hypertension in the elderly.

Purulent Pericarditis with Salmonella enterica Subspecies arizona in a Patient with Type 2 Diabetes Mellitus

Purulent pericarditis is a life-threatening disorder, even in the modern antibiotic era. Although diabetes mellitus is known to be associated with an increased risk of multiple types of infections, purulent pericarditis is extremely rare. We herein report an unusual case of pericarditis caused by Salmonella enterica subspecies arizona that was not associated with any evident underlying immunosuppressive disorder apart from uncontrolled type 2 diabetes mellitus. Because a pet snake was suspected as being the source of infection in the present case, patient education and a detailed review of exposure history could play an important role in treating patients with diabetes mellitus.