High-resolution ultrasonography for the diagnosis of brachial plexus root lesions.

The aim of this study was to investigate the feasibility of using high-resolution ultrasonography in the diagnosis of brachial plexus (BP) root lesions. A prospective study of ultrasonographic evaluation of BP nerve roots was performed in 37 patients with BP root lesions (29 with root injuries, 8 with tumors). The pre-operative ultrasonographic findings were compared with the surgical and pathohistological findings. All C5-7 roots were detected by ultrasonography in all patients, whereas 92% (68/74) of C8 and 51% (38/74) of T1 nerve roots were visualized. Among 29 patients with BP root avulsion, partial injuries or totally interrupted BP roots were detected in all patients. Cystic masses and neuromas were detected in 16 and 23 patients, respectively. In 8 patients with BP root tumors, 8 hypo-echoic masses were detected inside or partly outside of intervertebral foramina connecting to nerve roots. Surgical exploration revealed that there were 57 BP root avulsions in 29 patients. However, 2 T1 nerve root avulsions had been missed by pre-operative ultrasonography. Pathohistology revealed that all 8 BP root tumors pre-operatively diagnosed by ultrasonography were schwannomas. High-resolution ultrasonography can provide a convenient and accurate imaging modality for quick diagnosis and location of BP root lesions.

Differential diagnosis between pre- and postganglionic adult traumatic brachial plexus lesions by ultrasonography.

The goal of this study was to prospectively investigate the feasibility of preoperative ultrasonography evaluation in the differentiation between pre- and postganglionic traumatic brachial plexus lesions. Two expert radiologists employed ultrasonography to observe the morphology of the brachial plexus in 23 patients with suspected traumatic brachial plexus lesions and 40 healthy volunteers. The detection rate was 100% (126/126) for the C5 through C7 nerve roots and upper and middle trunks and three fascicles, 84% (106/126) for the C8 roots and the lower trunks and 64% (81/126) for T1 roots in all subjects. Surgical inspections found 58 lesions in 23 patients (40 preganglionic lesions and 18 postganglionic lesions). Ultrasonography detected most of the brachial plexus lesions (56/58) but misjudged two preganglionic and two postganglionic lesions. The rate of differentiation was 93% (52/56). This study demonstrated that ultrasonography is a useful but experience-dependent supplemental imaging technique for preoperative diagnosis of brachial plexus lesions and differentiation between pre- and postganglionic brachial plexus lesions.

[Inhibitory effects of rosiglitazone against endothelin-1-induced proliferation of rat cardiac myocytes: the role of PKC-c-fos pathway].

OBJECTIVE: To investigate the mechanism of rosiglitazone (RSG, the activator of peroxisome proliferators activated receptor lambda) for inhibiting endothelin-1 (ET-1)-induced neonatal rat cardiac myocyte hypertrophy and the role of protein kinase C (PKC) and c-fos. METHODS: In vitro cultured neonatal rat cardiac myocytes were treated with ET-1, phorbol ester (PMA, the PKC activator), ET-1+RSG, ET-1+chelerythrine (che, the PKC inhibitor), PMA+RSG, or without treatment (control), respectively. The effects of RSG on the protein content, (3)H-leucine incorporation, PKC activity and C-fos protein expression were observed in the cardiac myocytes stimulated with ET-1 or PMA. RESULTS: After two days of culture, the intracellular protein content in ET-1 group and PMA group were increased by 15% (339-/+15 microg/ml) and 13% (329-/+14 microg/ml) as compared with the control cells (290-/+13 microg/ml), respectively (P<0.01). Compared with the ET-1 group, cells treated with ET-1+10(-8) mol/L RSG, ET-1+10(-7) mol/L RSG, and ET-1+che showed decreased intracellular protein content by 10% (303-/+14 microg/ml, P<0.05), 12% (292-/+11 microg/ml, P<0.05), and 13% (291-/+12 microg/ml, P<0.01), respectively. The intracellular protein content in PMA+10(-7) mol/LRSG group was decreased by 10% (P<0.05) in comparison with the PMA group. RSG inhibited protein synthesis enhancement and increased (3)H-leucine incorporation induced by ET-1 and PMA, and antagonized the effects of ET-1 and PMA in promoting PKC activity and c-fos protein expression in the myocytes. CONCLUSION: The inhibitory effect of RSG on ET-1- or PMA-induced myocyte hypertrophy is associated with PKC-c-fos pathway.

[Prognostic value of ventricular longitudinal systolic velocities and maximal oxygen consumption in patients with dilated cardiomyopathy].

OBJECTIVE: To compare the prognostic value of regional longitudinal ventricular systolic velocities with that of maximal oxygen consumption (VO(2max)) in patients with dilated cardiomyopathy (DCM). METHODS: VO(2max) derived from cardiopulmonary exercise tests and regional longitudinal ventricular systolic velocities obtained from tissue Doppler imaging were compared in 18 DCM patients with cardiac events (death, cardiac transplantation, hospitalization, group A) and 24 patients without cardiac events (group B). Peak velocities during isovolumic contraction (is) and ejection (ez) were interrogated at the mitral or tricuspid annulus (site 1), at the mid parts of the walls (site 3, at the level of papillary muscle), and at the midpoints (site 2) between sites 1 and 3 of interventricular septum (S), lateral wall of LV (L) and of RV (R) in apical 4 chambers view. RESULTS: R1is, R2is, R2ez, R3is, S1is, S1ez, S2ez, L1is, L1ez and L2ez of group A were significantly lower than those in group B (all P < 0.05). Independent of VO(2max), high sensitivity and specificity were shown for R3ez, S1ez, L1ez, L1is, L2is and L3is in predicting cardiac events of DCM patients. CONCLUSION: LV and RV systolic velocities could independently predict cardiac events in DCM patients.

[Relationship between cardiomyocyte protein synthesis and cell viability].

OBJECTIVE: To observe the relationship between protein sythesis and cardiomyocyte viability in neonatal rats. METHODS: The protein sythesis in neonatal rat cardiomyocytes was measured according to Brandford's method, the absorbance at 490 nm (A(490 nm)) of the cells was measured with MTT assay and the cell viability evaluated by the ratio of A(490 nm) to the total cell number. RESULTS: ET-1 increased cardiomyocyte protein synthesis dose-dependently, and this effect was attenuated by the application of lacidipine and tetramethylpyrazines Higher doses of ET-1 resulted in lower A(490 nm)/total cell number ratio, which was further lowered by larcidipine and tetramethylpyrazine. CONCLUSION: The status of protein synthesis is not associated with the viability of neonatal rat cardiomyocytes.