Ultrasound evidence of the optimal wrist position for radial artery cannulation

Purpose

Radial artery cannulation is a common medical procedure for anesthesia and critical care. To establish the ideal wrist position for radial artery cannulation, we performed ultrasound examinations of the radial artery to investigate the effect of the angle of wrist extension on radial artery dimensions.

Clinical features

Measurements were performed in 17 healthy subjects and 17 surgical patients scheduled for coronary artery bypass graft (CABG) surgery. The radial artery was echographically visualized near the styloid process of the radius at the wrist. Radial artery dimensions were measured at wrist joint angles of 0, 15, 30, 45, 60 and 75°.

Observations

In both groups, radial artery height was affected by the wrist joint angle. Vessel height was decreased at 60° (one way ANOVA P = 0.027 vs 0°) and 75° (P < 0.001 vs 0, 15, 45°) in healthy subject and at 75° in CABG patients (P < 0.001 vs 0°). The mean differences in radial artery height at 0 and 75° were 0.33 ± 0.09 mm and 0.20 ± 0.06 mm for healthy and CABG patients, respectively. Vessel width was not affected by wrist joint angulation up to 75° of extension.

Conclusion

Our results demonstrate that in healthy subjects, radial artery dimensions are unaltered when the wrist joint is extended up to an angle of 45°. Extension at 60° for healthy subjects and 75° for CABG patients, however, results in a decrease in the height of the radial artery, which could possibly render arterial catheterization more difficult.     

Recurrence of juxtacortical chondrosarcoma arising on the rib

Juxtacortical chondrosarcoma developing on the surface of a bone is quite rare. We report a case of juxtacortical chondrosarcoma arising on the fourth rib of a 76-year-old man. Intraregional tumor resection was performed, but local recurrence was detected after 6 months. The patient underwent wide resection including the ribs, and reconstruction of the thoracic wall. He was released with a good prognosis after a year. This case emphasizes the importance of biopsy analysis before surgery to carefully evaluate tumor spread in the cartilage and performing wide resection even if the tumor is easily separated from the bone.     

Hepatocyte differentiation from embryonic stem cells and umbilical cord blood cells

With the development of regeneration medicine, many researchers have attempted hepatic differentiation from nonhepatic-origin cell sources. The differentiation of embryonic stem (ES) cells into hepatocyte-like cells has been reported in several papers. Mouse ES cells have shown a potential to develop into hepatocyte-like cells in vitro on the basis of hepatic gene expression after adding several growth factors. We transplanted cultured embryoid body (EB) cells (male) into female mice. A liver specimen of the recipient was examined by immunohistochemical staining for albumin and fluorescence in situ hybridization for the Y chromosome after transplantation. Both Y chromosome- and albumin-positive cells were recognized in the recipient female liver, and were considered to be hepatocyte-like cells derived from ES cells containing the Y chromosome. Many groups, including ourselves, have studied hepatocyte-like cell differentiation from umbilical cord blood cells (UBCs). We cultured nucleated cells isolated from UBCs. Using immunostaining, ALB-positive and CK-19-positive cells were recognized in the culture. Dual staining of ALB and CK-19 demonstrated that ALB was coexpresed with CK-19, suggesting the existence of hepatic progenitors. In this review, we consider recent studies of the differentiation of hepatocytes from nonhepatic origins, especially ES cells and umbilical cord blood.     

Postoperative cerebral hyperperfusion associated with impaired cognitive function in patients undergoing carotid endarterectomy

OBJECT: Cognitive impairment occurs in 20 to 30% of patients following carotid endarterectomy (CEA). The purpose of the present study was to determine whether postoperative cerebral hyperperfusion is associated with impairment of cognitive function in patients undergoing that procedure. METHODS: Cerebral blood flow (CBF) was measured using single-photon emission computerized tomography scanning before and immediately after CEA and on the 3rd postoperative day in 92 patients with ipsilateral internal carotid artery stenosis of 70% or greater. Hyperperfusion post-CEA was defined as a 100% increase or greater in CBF compared with preoperative values. Neuropsychological testing was also performed preoperatively and at the 1-, 3-, and 6-month follow-up examinations. At the 1-month postoperative neuropsychological assessment, 11 patients (12%) displayed evidence of cognitive impairment. In addition, the incidence of postoperative cognitive impairment in patients with post-CEA hype perfusion (seven [58%] of 12 patients) was significantly higher than that in patients without post-CEA hyperperfusion (four [5%] of 80 patients; p < 0.0001). A logistic regression analysis demonstrated that post-CEA hyperperfusion was the only significant independent predictor of postoperative cognitive impairment. Of the seven patients in whom post-CEA hyperperfusion and cognitive impairment were identified 1 month postoperatively, four (including three patients with hyperperfusion syndrome) remained cognitively impaired at the 3- and 6-month follow-up examinations. CONCLUSIONS: Postoperative cerebral hyperperfusion is associated with impairment of cognitive function in patients undergoing CEA. Furthermore, the development of hyperperfusion syndrome is associated with the persistence of postoperative cognitive impairment.     

Emergence of influenza B viruses with reduced sensitivity to neuraminidase inhibitors

Context  Very little is known about the frequency of generation and transmissibility of influenza B viruses with reduced sensitivity to neuraminidase inhibitors. Furthermore, transmission of resistant virus, whether influenza A or B, has not been recognized to date. Objective  To assess the prevalence and transmissibility of influenza B viruses with reduced sensitivity to neuraminidase inhibitors. Design, Setting, and Patients  Investigation of the neuraminidase inhibitor sensitivity of influenza B isolates from 74 children before and after oseltamivir therapy and from 348 untreated patients with influenza (including 66 adults) seen at 4 community hospitals in Japan during the 2004-2005 influenza season. Four hundred twenty-two viruses from untreated patients and 74 samples from patients after oseltamivir therapy were analyzed. Main Outcome Measure  Sialidase inhibition assay was used to test the drug sensitivities of influenza B viruses. The neuraminidase and hemagglutinin genes of viruses showing reduced sensitivity to neuraminidase inhibitors were sequenced to identify mutations that have the potential to confer reduced sensitivity to these drugs. Results  In 1 (1.4%) of the 74 children who had received oseltamivir, we identified a variant with reduced drug sensitivity possessing a Gly402Ser neuraminidase substitution. We also identified variants with reduced sensitivity carrying an Asp198Asn, Ile222Thr, or Ser250Gly mutation in 7 (1.7%) of the 422 viruses from untreated patients. Review of the clinical and viral genetic information available on these 7 patients indicated that 4 were likely infected in a community setting, while the remaining 3 were probably infected through contact with siblings shedding the mutant viruses. Conclusions  In this population, influenza B viruses with reduced sensitivity to neuraminidase inhibitors do not arise as frequently as resistant influenza A viruses. However, they appear to be transmitted within communities and families, requiring continued close monitoring.      

Combination therapy with oral PUVA and corticosteroid for recalcitrant alopecia areata

Alopecia areata (AA) is regarded as a tissue-specific autoimmune disease for which several therapies have been suggested to modify the immune reaction against HFs, such as contact immunotherapy, psoralen plus ultraviolet A (PUVA), corticosteroids, cyclosporine, minoxidil, and dithranol. However, severe type AA, such as alopecia totalis (AT) and alopecia universalis (AU), often show resistance against these therapies. We applied a combination therapy with oral corticosteroid and oral PUVA for intractable cases of AT and AU. These patients took 20 mg/day corticosteroid and were irradiated with UVA on the whole body 2 h after taking methoxsalen for 1 month. In all patients, the terminal hair on the whole scalp regrew after 2 months. Two patients had a relapse of hair loss 3 months after the termination of the treatment. FACS analysis revealed that the CD4⁺CD25^high and CD4⁺CD25⁺FOXP3⁺ Treg population in PBMC was increased after the combination therapy. Furthermore, the number of infiltrating cells decreased and FOXP3⁺ cells were often found in lesion skin after the combination therapy. Mitogen-induced proliferation tests showed low responses against PHA and Con A after the combination therapy. Taken together, the combination therapy may modify the systemic immune system and increase the number of Treg cells, resulting in improvement of recalcitrant AA.     

Inhibitory Effects of Fermented Brown Rice on Induction of Acute Colitis by Dextran Sulfate Sodium in Rats

Although the pathogenic mechanisms of inflammatory bowel diseases are not fully understood, colonic microbiota may affect the induction of colonic inflammation, and some probiotics and prebiotics have been reported to suppress colitis. The inhibitory effects of brown rice fermented by Aspergillus oryzae (FBRA), a fiber-rich food, on the induction of acute colitis by dextran sulfate sodium (DSS) were examined. Feeding a 5% and 10% FBRA-containing diet significantly decreased the ulcer and erosion area in the rat colon stained with Alcian blue. In another experiment, 10% FBRA feeding decreased the ulcer index (percentage of the total length of ulcers in the full length of the colon) and colitis score, which were determined by macroscopic observation. It also decreased myeloperoxidase activity in the colonic mucosa. Viable cell numbers of Lactobacillus in the feces decreased after DSS administration and was reversely correlated with severity of colitis, while the cell number of Enterobacteriaceae increased after DSS treatment and was positively correlated with colitis severity. These results indicate that FBRA has a suppressive effect on the induction of colitis by DSS and suggest FBRA-mediated modification of colonic microbiota.