Laryngotracheal separation using skin flap formation: a novel surgical procedure

Laryngotracheal separation is often performed to prevent intractable aspiration for children with severe mental and physical disabilities. However, tracheo-innominate artery fistula after surgery can occur as a severe complication and cause fatal hemorrhage. We have therefore developed a novel procedure to prevent tracheo-innominate artery fistula. Surgery was performed by making an H-shaped incision and creating skin flaps. The trachea was not raised anteriorly and the skin flaps were sutured to the trachea. We performed this procedure on nine patients, and no major complications occurred in any case. This procedure can be expected to reduce the occurrence of tracheo-innominate artery fistula.     

Effect of air-blowing variables on bond strength of all-in-one adhesives to bovine dentin

This study evaluated the effect of air-blowing variables on the microtensile bond strength (microTBS) of two all-in-one adhesives. A bonding agent was applied to the flat dentin surface of extracted bovine teeth, and the surface left undisturbed for 20 seconds. Gentle or intensive air-blowing was applied for five seconds, and the adhesive photopolymerized for 10 seconds. Resin composite paste was placed and cured after each bonding treatment. Specimens were subjected to microTBS test with a crosshead speed of 1.0 mm/min. Data were statistically analyzed using ANOVA, followed by Bonferroni post hoc test. When Clearfil tri-S Bond was bonded to dentin, the microTBS value of specimens applied with intensive air-blowing was significantly higher than that applied with gentle air-blowing (p<0.01). On the other hand, with Fluoro Bond Shake One, the microTBS value of specimens applied with intensive air-blowing was significantly lower than that applied with gentle air-blowing (p<0.01).     

Mucopolysaccharidosis IVA (Morquio A syndrome) and VI (Maroteaux–Lamy syndrome): under-recognized and challenging to diagnose

Objective

Mucopolysaccharidosis IVA (MPS IVA, or Morquio A syndrome) and VI (MPS VI, or Maroteaux–Lamy syndrome) are autosomal recessive lysosomal storage disorders. Skeletal abnormalities are common initial presenting symptoms and, when recognized early, may facilitate timely diagnosis and intervention, leading to improved patient outcomes. Patients with slowly progressing disease and nonclassic phenotypes can be particularly challenging to diagnose. The objective was to describe the radiographic features of patients with a delayed diagnosis of MPS IVA or VI.

Materials and Methods

This was a retrospective study. The records of 5 MPS IVA and 3 MPS VI patients with delayed diagnosis were reviewed. Radiographs were evaluated by a radiologist with special expertise in skeletal dysplasias.

Results

An important common theme in these cases was the appearance of multiple epiphyseal dysplasia (MED) with epiphyseal changes seemingly confined to the capital (proximal) femoral epiphyses. Very few patients had the skeletal features of classical dysostosis multiplex.

Conclusions

Radiologists should appreciate the wide phenotypic variability of MPS IVA and VI. The cases presented here illustrate the importance of considering MPS in the differential diagnosis of certain skeletal dysplasias/disorders, including MED, some forms of spondylo-epiphyseal dysplasia (SED), and bilateral Perthes-like disease. It is important to combine radiographic findings with clinical information to facilitate early testing and accurate diagnosis.     

Overexpression of acetyl-coenzyme A carboxylase beta increases proinflammatory cytokines in cultured human renal proximal tubular epithelial cells

Background  

We have identified the acetyl-coenzyme A carboxylase beta gene (ACACB) as a strong susceptibility gene to diabetic nephropathy in individuals with type 2 diabetes. To elucidate the mechanism by which ACACB contributes to conferring susceptibility to diabetic nephropathy, we examined the role of ACACB in human renal proximal tubular epithelial cells (RPTECs).     

Anatomical relationship between the morphology of the styloid process of the ulna and the attachment of the radioulnar ligaments

The radioulnar ligaments are the major stabilizers of the distal radioulnar joint under dynamic loading; however, anatomical detail regarding their attachment on the middle and distal thirds of the styloid process of the ulna remains unclear. Because previous anatomical studies included only old cadavers, their anatomical findings might not reflect the morphological features of younger and healthy specimens. This study investigated the anatomical features of the distal ulna, particularly the styloid process, to determine the attachment of the radioulnar ligaments to the styloid process and verified their direction and attachment to the styloid process in younger and healthy donors using magnetic resonance imaging (MRI). We investigated the morphological features of the distal ulna of 12 cadaveric wrists using micro-computed tomography (micro-CT). We also visualized and measured the distribution of the cortical bone thickness. We histologically analyzed three specimens in the axial plane and macroscopically analyzed seven specimens to examine the attachment of the radioulnar ligaments to the styloid process. In addition, we evaluated five wrists from living volunteers using 3.0 Tesla MRI. The distal ulna has a ridge on the dorsoradial aspect of the styloid process that corresponds to the attachment of the radioulnar ligaments. Micro-CT images after data processing revealed that the cortical thickness of the dorsoradial quadrant was thicker than that of the other quadrant at the proximal slice of the styloid process (p < 0.01), and that of the dorsoulnar (p = 0.021) and ulnopalmar (p < 0.01) quadrants at the middle slice. Histological analyses showed that the radioulnar ligaments were attached to the middle and distal thirds of the styloid process via chondral-apophyseal entheses. The direction of the fiber was dorsal in the middle third of the styloid process and changed to palmar in the distal third of the styloid process. The direction and attachment of the radioulnar ligaments on the styloid process were confirmed using MRI for younger and healthy participants. The radioulnar ligaments were attached to the dorsoradial ridge of the styloid process, which was confirmed by cortical bone thickening, histology at the attachment sites, and in vivo MR imaging. The directions of the radioulnar ligaments sterically intersected, which would satisfy both slipping stability and rotational mobility. These anatomical findings may provide the basis for biomechanical consideration of distal radioulnar joint stabilization.     

Negative reactions of BRAF mutation‐specific immunohistochemistry to non‐V600E mutations of BRAF

BRAF mutations are rare driver mutations in non‐small cell lung cancer (NSCLC), accounting for 1%–2% of the driver mutations, and the mutation spectrum has a wide range in contrast to other tumors. While V600E is a dominant mutation in melanoma, more than half of the mutations in NSCLCs are non‐V600E. However, treatment with dabrafenib plus trametinib targets the BRAF V600E mutation exclusively. Therefore, distinguishing between V600E and non‐V600E mutations is crucial for biomarker testing in NSCLC in order to determine treatment of choice. Immunohistochemistry (IHC) using the BRAF V600E mutation‐specific antibody is clinically used in melanoma patients, but little is known about its application in NSCLC, particularly with regard to the assay performance for non‐V600E mutations. In the present study, we examined 117 tumors with BRAF mutations, including 30 with non‐V600E mutations, using BRAF mutation‐specific IHC. None of the tumors with non‐V600E mutations, including two compound mutations, showed a positive reaction. Furthermore, all V600E mutations were positive except for one case with combined BRAF V600E and K601_W604 deletion. Our findings confirmed that the BRAF V600E mutation‐specific IHC is specific without any cross‐reactions to non‐V600E mutations, suggesting that this assay can be a useful screening tool in clinical practice.