Risk factors for dislocation of the ulnar nerve after simple decompression for cubital tunnel syndrome.

Anterior dislocation of the ulnar nerve is occasionally encountered after simple decompression of the nerve for treatment of cubital tunnel syndrome. The purpose of this study was to determine whether the incidence of dislocation of the nerve following simple decompression of the nerve is correlated with the patient's preoperative characteristics and/or elbow morphology. We studied 51 patients with cubital tunnel syndrome who underwent surgery at our institution. Intraoperatively, we simulated dislocation of the nerve after simple decompression by flexing the elbow after releasing the nerve in each patient. Univariate and multiple logistic regression analysis showed that young age and a small ulnar nerve groove angle are positively correlated with dislocation of the nerve. Our results suggest that patients who are young and/or have a sharply angled ulnar nerve groove identified radiographically have a high probability of experiencing anterior dislocation of the ulnar nerve after simple decompression.

Long-term follow-up of periarterial sympathectomy for chronic digital ischaemia.

This study investigates long-term clinical results (> 10 years) of periarterial sympathectomy in chronic ischaemic digits compared with intermediate-term results (3 years). Periarterial sympathectomy via the palm and volar wrist was carried out on 11 hands of seven patients with digital ischaemia but no gangrene or severe ulceration. The aetiology of ischaemia was Buerger's disease in four hands, collagen disease in three hands, and repetitive digital trauma in four hands. Subjective symptoms were evaluated at a mean follow-up period of 12 years. The efficacy of surgery was assessed objectively using thermography and plethysmography. Although five of seven patients continued on oral vasodilators and antiplatelet agents until the final follow-up, improvement of symptoms was maintained in all patients between intermediate- and long-term evaluations. Our results suggest that periarterial sympathectomy via the palm and wrist could prevent long-term aggravation of symptoms of chronic digital ischaemia when combined with adequate postoperative drug therapy.

Changes in blood circulation of the contralateral Achilles tendon during and after acupuncture and heating.

The purpose of this study was to investigate the effects of acupuncture and heating (application of hot pack) treatments on blood circulation in the contralateral Achilles tendon. During the treatments (10 min for acupuncture, 20 min for heating) and recovery period (40 min), the blood volume (THb) and oxygen saturation (StO2) of the treated and the non-treated tendons were measured using red laser lights. During both treatments, THb and StO2 of the treated tendon increased significantly from the resting level. The increased THb and StO2 of the treated tendon were maintained until the end of the recovery period after removal of the acupuncture needle, although these values decreased after removal of the hot pack. Although THb of the non-treated sides did not change during both acupuncture and heating treatments, it increased gradually after removal of the acupuncture needle or the hot pack. For both treatments, the amount of increase in THb of the non-treated tendon was significantly correlated to that of the treated tendon during the last phase of recovery period. These results obtained from the healthy subjects imply that blood circulation in the injured tendon in a plaster cast may be improved by applying acupuncture or heating treatments to the contralateral healthy limb.

A method for removing copper from charcoal of waste wood using an electrical current.

The reclamation of resources from wastes, through such activities as recycling various kinds of wastes and finding more ways to use them, is an important part of changing to a sustainable society. It is also important to ensure the safety of products by, for example, removing hazardous substances from recycled items. Wood is a type of demolition waste. The reuse and recycling of wood from demolition have not progressed much. To increase the number of ways of using wood wastes we have examined methods of making carbonized materials from them and using these carbonized materials to control indoor air pollution (Shibano et al., 2002). Research currently underway on ensuring the safety of recycled items includes investigating the behavior and other characteristics of hazardous substances that are, or may very well be, found in recycled items. It is known that the smoke arising from the process of carbonizing wood wastes is mutagenic. However, such mutagenic components become smoke and separate from carbonized materials, and, especially at temperatures of 800 degrees C and higher, they hardly remain in carbonized materials at all (Nakajima et al., 2003, 2004). In the carbonization of wood wastes containing hazardous metals such as CCA (Cr, Cu, As)-treated wood, substances that readily vaporize separate from the carbonized materials. One cannot expect, however, the same removal effect on metals that vaporize with difficulty, such as Cu, making it likely that they remain in the carbonized material (Takahashi et al., 2004). To examine methods of removing hazardous metals which may well remain in carbonized wood wastes, we investigated the removal and recovery of copper from charcoal with a high copper content by applying electricity (direct current) to it.

Prevention of diet-induced obesity by dietary isomerized hop extract containing isohumulones, in rodents.

OBJECTIVE: Isomerized hop extract (IHE), which consists mainly of isohumulones and is required in the beer brewing process, was investigated for its effects on diet-induced obesity in two strains of mice. DESIGN: C57BL/6N and KK-A(y) mice were fed a standard or high-fat diet containing IHE and their body and tissue weights were measured at various time points. Oral glucose tolerance tests (OGTT) and insulin tolerance tests (ITT) were carried out in high-fat diet-fed C57BL/6N mice. The effects of IHE on intestinal lipid absorption were examined in Wistar rats using a plasma triacylglycerol assay after oral administration of a lipid emulsion. Fecal lipid levels were also measured in these animals after they were fed a high-fat diet containing IHE for 15 days. The effects of IHE on pancreatic lipase activity and the expression of genes involved in hepatic lipid metabolism were also examined using an in vitro assay and quantitative RT-PCR, respectively. RESULTS: Supplementation of high-fat-containing chow with IHE reduced body weight gain and improved glucose tolerance in our experimental mice. A reduction in body weight gain was also observed in C57BL/6N mice fed a standard diet containing IHE. Wistar rats fed a high-fat diet containing IHE showed reduced plasma triacylglycerol levels and an increase in their fecal lipid excretion. Similarly, their pancreatic lipase activity was inhibited and their elevation in plasma triacylglycerol levels seen after the oral administration of lipid emulsion was significantly suppressed. IHE-fed mice showed an increased expression in their lipid oxidation genes and a decreased expression in genes involved in triacylglycerol biosynthesis. CONCLUSION: The inhibition of intestinal dietary fat absorption may be the mechanism by which IHE induces its weight-lowering effects in high-fat diet-fed mice. The modulatory effect of IHE on lipid metabolism may also, at least partly, be responsible for its beneficial effects on body weight gain. These results suggest that IHE may be helpful in humans in preventing diet-induced obesity and perhaps even metabolic syndrome, the latter of which is known to be associated with obesity.

Inhibitory effect of pain-eliciting transcutaneous electrical stimulation on vibration-induced finger flexion reflex in the human upper limb.

We studied the effects of non-pain transcutaneous electrical stimulation (TES) and pain-eliciting TES on vibration-induced finger flexion reflex (VFR) in 12 healthy volunteers. Tonic finger flexion reflex in the upper limb was induced by the application of vibratory stimulation on the volar side of the middle fingertip in the right hand before and after TES. Non-pain TES or pain-eliciting TES was applied on the skin between the bases of the first and second metacarpals in the right hand dorsal area in a crossover design. Pain-eliciting TES inhibited VFRs significantly (Fisher's PLSD, p <0.01), compared to those of the time-control group during and after TES. VFRs were reduced approximately to 63.8% and 78.6% of prestimulation flexion force during and after pain-eliciting TES, respectively. Nonpain TES did not inhibit VFR. These results suggest that pain-conducting afferent fibers have inhibitory neuronal connection over the ipsilateral reflex circuits of VFR in the upper limb.

Surgical treatment for chronic radial head dislocation.

BACKGROUND: The treatment of chronic radial head dislocation remains controversial. High rates of redislocation and complications have been reported after surgery. In our view, correction of malalignment with ulnar osteotomy is the key to a good surgical result. METHODS: Since 1975, twenty-two patients were treated surgically for chronic radial head dislocation at our hospital. The procedure consisted of open reduction of a dislocated radial head followed by radial and/or ulnar osteotomy, with or without reconstruction of the annular ligament or by reconstruction of the annular ligament alone. The ages of the patients ranged from four to twenty years. In 1991, we modified the surgical technique by performing an oblique ulnar osteotomy with angulation and elongation and rigid plate fixation. Bone-grafting at the osteotomy site was also performed if necessary. A cast was applied with the forearm in neutral rotation and was worn for two to four weeks. Nine patients were treated with this modified technique. RESULTS: The mean interval between the initial injury and the reconstructive surgery was ten months. There were no serious surgical complications. Of the thirteen patients treated before 1991, four had a good reduction and seven had redislocation. Seven patients had restricted forearm rotation postoperatively. Of the nine patients treated with the modified osteotomy since 1991, seven had a good reduction. Two patients, who had had slight radial head deformity preoperatively, had subluxation postoperatively. Two patients had restricted forearm rotation. CONCLUSIONS: Since we modified our technique for ulnar osteotomy, good reduction of the radial head has been achieved without causing serious contracture. Both angulation and elongation of the ulna are required to allow the radial head to reduce.

Time-dependent potentiation of the beta-cell is a Ca2+-independent phenomenon.

When isolated rat pancreatic islets are treated with 16.7 mM glucose, a time-dependent potentiation (TDP) of insulin release occurs that can be detected by subsequent treatment with 50 mM KCl. It has been thought that TDP by glucose is a Ca2+-dependent phenomenon and only occurs when exposure to glucose is carried out in the presence of Ca2+. In contrast to this, we now demonstrate TDP under stringent Ca2+-free conditions (Ca2+-free buffer containing 1 mM EGTA). In fact, under these Ca2+-free conditions glucose caused an even stronger TDP than in the presence of Ca2+. TDP induced by glucose in the absence of extracellular Ca2+ was unaffected by inhibitors of protein kinase C (PKC). However, cerulenin or tunicamycin, two inhibitors of protein acylation, eradicated TDP without affecting glucose metabolism. The TDP by glucose was not associated with an increase in the cytosolic free Ca2+ concentration ([Ca2+]i) during subsequent treatment with high K+. Exposure of islets to forskolin under Ca(2+)-free conditions did not cause TDP despite a large increase in the cellular cAMP levels. In conclusion, glucose alone induces TDP under stringent Ca2+-free conditions when [Ca2+]i was significantly lowered. Protein acylation is implicated in the underlying mechanism of TDP.

[Influence of vibration on the equilibrium of patients with unilateral labyrinthine dysfunction].

To determine the role of proprioceptors of different skeletal muscles in posture control in patients with unilateral labyrinthine dysfunction (ULD), we studied the effect of vibration on those muscles by postulography. Subjects were 59 healthy people and 20 ULD patients. We measured the length of the displacement of the center of gravity, maximum sway length, and sway area. Significant differences were observed between healthy and ULD subjects on stimulation of the muscle groups of the upper and lower extremity during vibration. In patients with ULD, vibration to the dorsal neck muscles caused a deviation toward the diseased side. We speculate that the upper dorsal neck muscle plays an important role in maintaining body balance in the frontal plane in patients with ULD. The upper and lower extremity muscles play a significant role in adjusting standing posture.

Size-related and size-unrelated functional heterogeneity among pancreatic islets.

Functional heterogeneity of pancreatic islets was systematically analyzed for the first time using freshly isolated single rat pancreatic islets. First, 60 islets were sequentially exposed to 3, 9.4, 15.6, and 24.1 mM glucose for 30 min each in incubation experiments: 36 (60%) responded in a concentration-dependent and 19 (32%) in an all-or-none manner, and 5 (8%) islets did not respond to high glucose. As a group, the larger the islet, the higher the beta cell glucose sensitivity. However, glucose-stimulated elevation of [Ca2+]i in the beta cell. insulin/glucagon ratio in the islet, and expression of glucose transporter 2, glucokinase, and pancreatic duodenal homeobox factor-1 in the beta cell were not significantly related to islet size. Second, 50 islets were stimulated with 16.7 mM glucose in perifusion. A biphasic insulin release was found in 39 (78%), and no or little first phase response in 11 (22%) islets, irrespective of the islet size. Nevertheless, when the response was plotted as a group, it was clearly biphasic. Islet size, insulin content and the amount of insulin release were positively correlated with each other. In conclusion, there are size-related and size-unrelated functional diversity among pancreatic islets. The reason for such heterogeneity remained to be determined.

Primary osteogenic sarcoma of a finger proximal phalanx: a case report and literature review.

Osteogenic sarcoma of the small bones of the hand is rare with only 15 cases documented. We describe a 12-year-old boy with an osteogenic sarcoma of the proximal phalanx of the middle finger. Wide excision in the form of ray amputation with a wide surgical margin was performed after neoadjuvant chemotherapy consisting of combined high-dose methotrexate, doxorubicin, ifosfamide, and cisplatin. To restore maximum function the index ray was transferred to the base of the third metacarpal. Adjuvant chemotherapy was administered subsequently. At 28-month follow-up evaluation there was no evidence of local recurrence of disease or distant metastasis and both function and appearance were good.

Mechanism of urinary tract crystal formation following biphenyl treatment.

Coadministration of biphenyl and KHCO3 in the diet of male rats for 13 weeks produced urine crystals, which, by means of LC-MS/MS analyses, were determined to be composed of the potassium salt of 4-hydroxy-biphenyl-O-sulfate (4-HBPOSK). Biphenyl alone or biphenyl with KCl or NaHCO3 in the diet did not produce urine crystals. It was found that the higher concentration of potassium in the urine and the alkaline pH induced by feeding KHCO3 to rats resulted in the formation of urine crystals of 4-HBPOSK due to 4-HBPOSK solubility being lower in urine than in plasma. Urine crystals of 4-HBPOSK produced hyperplasia of the transitional epithelium of the ureter, ureteral obstruction, and hydronephrosis in the urinary tract.

Switch-based mechanism of kinesin motors.

Kinesin motors are specialized enzymes that use hydrolysis of ATP to generate force and movement along their cellular tracks, the microtubules. Although numerous biochemical and biophysical studies have accumulated much data that link microtubule-assisted ATP hydrolysis to kinesin motion, the structural view of kinesin movement remains unclear. This study of the monomeric kinesin motor KIF1A combines X-ray crystallography and cryo-electron microscopy, and allows analysis of force-generating conformational changes at atomic resolution. The motor is revealed in its two functionally critical states-complexed with ADP and with a non-hydrolysable analogue of ATP. The conformational change observed between the ADP-bound and the ATP-like structures of the KIF1A catalytic core is modular, extends to all kinesins and is similar to the conformational change used by myosin motors and G proteins. Docking of the ADP-bound and ATP-like crystallographic models of KIF1A into the corresponding cryo-electron microscopy maps suggests a rationale for the plus-end directional bias associated with the kinesin catalytic core.

Fibroblast growth factor-induced gene expression and cartilage pattern formation in chick limb bud recombinants.

To clarify the roles of fibroblast growth factors (FGF) in limb cartilage pattern formation, the effects of various FGF on recombinant limbs that were composed of dissociated and reaggregated mesoderm and ectodermal jackets were examined. Fibroblast growth factor-soaked beads were inserted just under the apical ectodermal ridge (AER) of recombinant limbs and the recombinant limbs were grafted and allowed to develop. Control recombinant limbs without FGF beads formed one or two cartilage elements. Recombinants with FGF-4 beads formed up to five cartilage elements, which were aligned along the anteroposterior (AP) axis. Each cartilage element showed digit-like segmentation. In contrast, recombinants with FGF-2 beads showed formation of multiple thick and unsegmented cartilage rods, which elongated inside and outside the AP plane from the distal end of the recombinants. Recombinants with FGF-8 beads formed a truncated cartilage pattern and recombinants with FGF-10 beads formed a cartilage pattern similar to that of the control recombinants. The expression of the Fgf-8, Msx-1 and Hoxa-13 genes in the developing recombinant limbs were examined. FGF-4 induced extension of the length of the Fgf-8-positive epidermis, or AER, along the AP axis 5 days after grafting, at which time the digits are specified. FGF-2 induced expansion of the Msx-1-positive area, first in the proximal direction and then along the dorsoventral axis. The functions of these FGF in recombinant and normal limb patterning are discussed in this paper.

Experimental study of vascularized nerve graft: evaluation of nerve regeneration using choline acetyltransferase activity.

A comparative study of nerve regeneration was performed on vascularized nerve graft (VNG) and free nerve graft (FNG) in Fischer strain rats. A segment of the sciatic nerve with vascular pedicle of the femoral artery and vein was harvested from syngeneic donor rat for the VNG group and the sciatic nerve in the same length without vascular pedicle was harvested for the FNG group. They were transplanted to a nerve defect in the sciatic nerve of syngeneic recipient rats. At 2, 4, 6, 8, 12, 16, and 24 weeks after operation, the sciatic nerves were biopsied and processed for evaluation of choline acetyltransferase (CAT) activity, histological studies, and measurement of wet weight of the muscle innervated by the sciatic nerve. Electrophysiological evaluation of the grafted nerve was also performed before sacrifice. The average CAT activity in the distal to the distal suture site was 383 cpm in VNG and 361 cpm in FNG at 2 weeks; 6,189 cpm in VNG and 2,264 cpm in FNG at 4 weeks; and 11,299 cpm in VNG and 9,424 cpm in FNG at 6 weeks postoperatively. The value of the VNG group was statistically higher than that of the FNG group at 4 weeks postoperatively. Electrophysiological and histological findings also suggested that nerve regeneration in the VNG group was superior to that in the FNG group during the same period. However, there was no significant difference between the two groups after 6 weeks postoperatively in any of the evaluations. The CAT measurement was useful in the experiments, because it was highly sensitive and reproducible.

The fibronectin-derived antiadhesive peptides suppress the myofibroblastic conversion of rat hepatic stellate cells.

We previously found that fibronectin (FN) had a functional site (YTIYVIAL sequence in the 14th type III module) suppressing the integrin-mediated cell adhesion to extracellular matrix. FN-derived peptides containing this antiadhesive site were also shown to regulate cellular processes such as proliferation, differentiation, and apoptosis. The present study shows that the FN-derived antiadhesive peptides suppress the myofibroblastic conversion of rat hepatic stellate cells (HSC). Freshly isolated HSC underwent myofibroblastic conversion during culture in the presence of FBS, as evaluated by indices representing the phenotypic activation of HSC, including increased proliferation, consumption of vitamin A-enriched lipid droplets, and expression of alpha-smooth muscle actin. However, appearance of these myofibroblastic characters was suppressed by coculturing HSC with the FN-derived antiadhesive peptides. On the other hand, the activated HSC, which had already acquired the myofibroblastic phenotype through repeated subculture, secreted FN and then stimulated matrix assembly of ED-A (+) cellular FN as well as plasma FN, while the FN-derived antiadhesive peptides inhibited them. Furthermore, the FN-derived antiadhesive peptides suppressed the integrin-mediated adhesion of the primary HSC to plasma FN and ED-A (+) cellular FN substrates. These results suggested that the FN-derived antiadhesive peptides down-regulated the myofibroblastic conversion of HSC in an indirect manner by inhibiting the integrin-mediated adhesive interaction of HSC with ED-A (+) cellular FN.

Neurohistochemical analysis of regeneration in rat peripheral nerve after end-to-side neurorrhaphy.

We investigated the regenerative capacity of motor nerves repaired by end-to-side or end-to-end neurorrhaphy, using choline-acetyltransferase (ChAT) activity measurement or histological analysis. The right medial gastrocnemius nerves (MGNs) of 62 male Fisher strain rats were transected and divided into three groups. In group 1, the distal ends of the MGN were coapted to the side of the lateral gastrocnemius nerve, using a Y-shaped silicone tube in end-to-side neurorrhaphy. In group 2, the nerve ends were reconnected by the traditional end-to-end technique. In group 3, the nerve ends were separated and remained unrepaired. The MGNs were sampled 1, 2, and 3 months postoperatively for histological examinations and ChAT activity measurement. The medial gastrocnemius muscle (MGM) was also sampled for histological evaluations. Axonal regeneration of MGN and the recovery of MGM to nearly normal histology and weight were observed in groups 1 and 2 3 months postoperatively. Although there were no significant differences in ChAT values between groups 1 and 2, the values were significantly larger than that of group 3 3 months postoperatively. These findings suggested that end-to-side neurorrhaphy would be an alternative treatment for peripheral nerve injury in certain clinical situations.

Differences between the Lewis and Sprague-Dawley rats in chronic inflammation induced norepinephrine sensitivity of cutaneous C-fiber nociceptors.

We investigated whether there are any differences between the Lewis and Sprague-Dawley (SD) rats in chronic inflammation-induced norepinephrine (NE) sensitivity of nociceptors. Activities of C-fiber nociceptors innervating rat hairy hindpaw skin were recorded in an in vitro skin-nerve preparation. Sixty-five percent of C-fibers from inflamed Lewis rats were excited by NE (10 microM), against only 38% of C-fibers from inflamed SD rats. The average of the total impulses evoked in response to NE was also significantly higher in Lewis rats. The alpha2-adrenoceptor antagonist CH 38083 (10 microM) and yohimbine (10 microM) consistently blocked the NE-excitation of both strains. These results show that after chronic inflammation, C-fiber nociceptors of Lewis strain rats have a stronger sensitivity to NE, and that alpha2-adrenoceptors are predominately involved in the NE-sensitivity of inflamed rats in both strains.