[Protective effect of tumor necrosis factor-alpha on motor neurons after peripheral nerve injury].

OBJECTIVE: To investigate the protective effect of tumor necrosis factor-alpha(TNF-alpha) on spinal motor neurons after peripheral nerve injury. METHODS: Twenty Wistar rats were divided into two groups, the right sciatic nerves of 20 Wistar rats were transected, the proximal stumps were inserted into a single blind silicone tube. 16 microliters of normal saline(NS) and TNF-alpha(30 U/ml) were injected into the silicone tubes. After 2 weeks, the 4th, 5th lumbar spinal cord were taken for examination. Enzyme histochemical technique and image analysis were used to show acetylcholinesterase(AChE) and nitric oxide synthase(NOS) activity of spinal motor neurons. RESULTS: The number of AChE and NOS staining neurons were 8.65 +/- 1.98 and 5.92 +/- 1.36 in the experimental group and 6.37 +/- 1.42 and 8.67 +/- 1.45 in the control group respectively, there were significant difference between the two groups(P < 0.01). CONCLUSION: It suggests that TNF-alpha has protective effect on motor neurons after peripheral nerve injury.

[Observation of reconstruction of wrist joint by replacement of distal end of radius with vascularized fibular head].

OBJECTIVE: This paper is aimed to observe the long-term result of reconstruction of wrist joint by replacing distal end of radius with vascularized fibular head in patient of giant tumor. METHODS: From July 1978 to November 1993, 12 cases of giant tumor of distal end of radius were treated by this procedure and followed up for 6 months to 15 years, and the movement range of wrist, grip strength, and pain were evaluated. RESULTS: The painful wrist released in 11 cases, only one case still existed mild pain and felt discomfortable. The average range of movement of wrist joint was 34.05 degree in volar flexion, 52.80 degree in dorsal extension, 26.25 degree in ulnar deviation, and 19.75 degree in radial deviation, and average grip strength was 44.6 kg. Compared with the contralateral side, there were accounted for 46.2%, 72.7%, 76.1%, 80.6%, and 76.7% respectively. CONCLUSION: Replacement of distal end of radius with fibular head to reconstruct wrist joint can restore function of carpal joint, which is proved to be a safe and effective method.

Motoneurotrophins derived from limb buds protect the motoneurons in anterior spinal cord after nerve injury and promote nerve regeneration.

The effects of limb bud-derived motoneurotrophins (LBMNTs) as seen in the motoneurons in the anterior spinal cord and sciatic nerve regeneration of adult rats, were evaluated in the present study. A nerve regeneration chamber with a nerve gap of 9 mm was created by suturing the proximal and distal ends of a random sciatic nerve into a silicone tube after removal of a 5 mm piece of nerve in the distal end, The chamber of the experimental group was filled with 34.34 microg LBMNTs and PBS (0.01 mol/ml, pH 7.0),and the control group with PBS only. At 1 day, 4 days, 1 week, 2 weeks, 4 weeks and 6 weeks post surgery, the content of acetylcholine esterase (AchE) and acid phosphatase (ACP) of the anterior spinal cord (injured side) was quantified, and the corresponding motoneuron's ultrastructure and the existant ratio were also examined. Meanwhile, the regenerated nerve from within the silicone tube was examined at 2, 4 and 6 weeks post surgery for histological studies at both the light microscopic and ultrastructural levels. The experimental group showed a smaller decrease of AchE and an increase of ACP, a larger existant ratio of motoneurons, better ultrastructure and a more mature regenerated nerve based on a larger diameter of the regenerated nerve trunk, a greater number of axons and thicker myelin sheaths than the control group. So it was concluded that LBMNTs had a high activity of protecting motoneurons in the anterior spinal cord after nerve injury and promoting nerve regeneration, and it may be a new source of neurotrophic factors (NTFs).

N-acetyltransferase activity in the quail (Coturnix coturnix jap) duodenum.

The activity and kinetics of N-acetyltransferase (NAT) in the quail duodenum were studied by radioenzymatic assay. NAT activity was highest when incubated under 37 degrees C, at pH 5.8 for 15 sec. Of the four substrates tested (tryptamine, 5,6-dihydroxytryptamine, serotonin, and N-acetylserotonin at concentrations of 0.08-4 mM), only tryptamine showed the substrate saturation phenomenon when incubated with the duodenal enzyme and acetyl-14C-coenzyme A. The saturation concentration of tryptamine was about 4 mM. Using the double reciprocal plot and regression equation, the Michaelis constant (Km) and maximal rate (Vmax) of NAT activity were found to be 0.204 mM and 0.917 nmol.mg protein-1.min-1, respectively. Diurnal study demonstrated higher NAT activity at middark (3.7 nmol.mg protein-1.min-1) and lower activity at midlight (2.4 nmol.mg protein-1.min-1), suggesting a circadian rhythm of the enzyme activities in the quail duodenum.

Comparison of effects of MPTCP and PTCP ceramics implanted for the treatment of bone defects in rabbits.

The magnetic porous tricalcium phosphate (MPTCP) and porous tricalcium phosphate (PTCP) ceramic cylinders were implanted into right and left bone defects of rabbits' radii in order to determine the utility of the MPTCP ceramics. Based on naked eye inspection, light and scanning electron microphotography, roentgenography, quantitative histological measurement of new bone formation and anti-break test for a period of 5 months. The results showed that the two kinds of ceramics were biocompatible with human tissue. MPTCP ceramics could induce more new bone formation than PTCP ceramics. Treatment of fractures with synthetic calcium phosphate ceramics and magnetic fields were discussed.

[Memory-improving effect of aqueous extract of Astragalus membranaceus (Fisch.) Bge].

The study shows that the aqueous extract of Astragulus membranaceus (AMWE) can improve the anisodine-induced impairment on memory acquisition as well as the alcohol-elicited deficit of memory retrieval (number of errors were reduced and latent period was prolonged) in step down, and can also prolong the gasping duration of mice after decapitation at doses of 50g/kg (ig) for 7 days.

[Central inhibition action of Valeriana jatamansii Jones].

The use of water extract (ip or ig) of Valeriana jatamansii together with pentobarbital sodium can enhance sedative and hypnotic effect in mice, inhibit the spontaneous activity in mice, and antagonize convulsive action induced by thiosemicarbazide (TSZ). Although ineffective on the convulsion induced by picrotoxin (PT), it can prolong the latent period of convulsion induced by PT in mice. The number of writhings in mice can be reduced after ip or ig water extract.

New bone formation in the in vivo implantation of bioceramics. A quantitative analysis.

Two kinds of synthetic biomaterial, porous tricalcium phosphate (PTCP) and magnetic porous tricalcium phosphate (MPTCP) ceramic granules were implanted in rat femur. In the period of 4 months, the assessment of serial histological sections, scanning electron microphotographs and quantitative analysis of bone formation in the sections showed that both ceramics are biocompatible and degradable in vivo. More new bone formation occurred in the MPTCP group. Endochondral ossification was seen in both groups. The quantitative analysis in this study is reliable, and may be suitable to the similar experimental models.

Artificial bone of porous tricalcium phosphate ceramics and its preliminary clinical application.

The authors have prepared the artificial bone of porous tricalcium phosphate ceramics according to an appropriate formula and manufacturing technology. Physical and chemical testing shows that it possesses several distinguishing features: the communicating pores and macro/micropores; mean pore size, 380 microns (from 240 microns to 510 microns); porosity, 46.4%; and compressive strength, 97.4 kg/cm2. It consists of CaO (49.09%) and P2O5 (48.84%). The testing of its biocompatibility shows that it is devoid of systemic or local toxicity, and free of irritation or foreign body response in tissues, and it does not result in hemolysis or mutation. The new bone readily grows into its pores with direct contact to the implanted material. 11 cases of bone defects were treated with this artificial bone with satisfactory results.

Analysis of the biocompatibility of magnetic porous tricalcium phosphate ceramics in rat femurs.

A new biomaterial, magnetic porous tricalcium phosphate ceramics (MPTCP), may be used for repairing defects in bones as a substitute for bone grafting. This study was designed to examine its biocompatibility and the systemic toxicity. The ceramic sections, approximately 15.3 mg, were implanted into both proximal femurs of 10 male and 10 female albino SW rats. An equal number of male and female animals served as sham-operated controls. Implantation of MPTCP ceramics in rat femurs had no deleterious effects on body weight, organ/body weight ratio, and on blood, liver and kidney functions. Plasma levels of inorganic phosphorus were significantly elevated in rats implanted with MPTCP ceramics. Alkaline phosphatase values in plasma in the experimental group were equal to those in the control group. Photomicrographs, radiographs and scanning electron photomicrographs of the rat femurs implanted with MPTCP ceramics demonstrated excellent bone association with implants and growth of some new bone into MPTCP ceramics. In conclusion, MPTCP ceramics are biocompatible and suitable for the reconstruction of bones.

A histological observation on the flexor tendon healing within intact sheath.

In this study we allowed the sutured chicken flexor tendons to glide back into the uninjured sheaths in order to keep the healing process of flexor tendon from being affected by the healing of surrounding wounded tissues. By observing 12 chickens, 72 digits, with light microscope and transmission electron microscope, it was found that the visceral and parietal synovium of the sheath were the regions with earliest and most active cell proliferation and the major source of repairing cells during the healing process of the flexor tendon. Tendon cells had the ability of intrinsic healing, but delayed as compared to synovium cells. Adhesion between intact parietal synovium and healing tendon and its surrounding tissue could not be avoided.

Fluctuation of blood melatonin concentrations with age: result of changes in pineal melatonin secretion, body growth, and aging.

Melatonin in the systemic circulation of rats fluctuates with age, and the causes for such changes were investigated. Male rats (aged 7 days, 16 days, 18 days, 20 days, 30 days, 48 days, 60 days, and greater than 17 months) were adapted under a lighting regime of 12L:12D for at least 7 days. Pineals and blood samples from the trunk or confluens sinuum were collected in the dark period. Melatonin in tissues was extracted, identified, and determined by gas chromatography-mass spectrometry (GC-MS) and/or radioimmunoassay. Tissue melatonin levels obtained by radioimmunoassay correlated closely with those quantified by GC-MS. Thus, the melatonin radioimmunoassay used is a reliable assay method for melatonin in the plasma and pineal of the rat. Plasma melatonin in the confluens sinuum of rats exhibited episodic release superimposed on a basal release pattern. It was suggested that there are two pools of melatonin in the pineal gland, a readily releasable pool and a bound pool. The mean plasma levels of melatonin in the confluens sinuum of rats increased with age with the highest level recorded at 60 days old and declined to a lower level at greater than 17 months old. The above age-related changes, being similar to the alterations in pineal melatonin levels with growth and aging, suggest that, under our experimental conditions, levels of pineal melatonin increase or decrease with its secretory rate. In developing rats, the age-related increase in the rate of secretion of pineal melatonin as reflected by increases in melatonin levels in the confluens sinuum or pineal melatonin content before adulthood is different from the changes in melatonin levels in the systemic circulation which showed an early developmental rise, followed by an active period and then a prepubertal decline. However, when the body weight was taken into consideration, changes in the levels of pineal melatonin content per 100 gm body weight or the calculated blood melatonin levels (plasma melatonin in the confluens sinuum/body:head ratio) correlated well with the fluctuation of serum melatonin in the systemic circulation. Thus, the developmental changes in the concentrations of melatonin in the general circulation are the result of 1) changes in the rate of pineal melatonin secretion and 2) increase in the dilution factor because of increase in body size. In old rats, levels of plasma melatonin in the confluens sinuum and pineal melatonin content decreased indicating a decline in the rate of pineal melatonin secretion.(ABSTRACT TRUNCATED AT 400 WORDS)

[The supinator syndrome. An anatomic and clinical study]. / Das Supinatorsyndrom. Eine anatomische und klinische Studie.

The posterior interosseous syndrome appears in two forms, a) paralytical, and b) painful. In this investigation the authors report on twelve operated patients with painful posterior interosseous or "radial tunnel" syndrome. The intraoperative findings in the arcade of Frohse are compared with the findings on preparation of ten recently deceased. It was especially significant that in ten of twelve cases there was found intraoperatively a tendinous type of arcade. In the cadaveric studies the authors encountered this type of tendinous arcade in only two of ten specimens. Based on these findings, the authors conclude that the tendinous arcade of Frohse is an important factor in the development of the posterior interosseous syndrome.

[The supinator syndrome--an anatomical and clinical study]. / Das Supinatorsyndrom--eine anatomische und klinische Studie.

The interosseus posterior syndrome appears in two forms: a) the paralytical interosseus posterior syndrome, b) the painful (afferent) interosseus posterior syndrome. We report in this investigation about 12 operated patients with painful interosseus posterior syndrome. The intraoperative findings in the arcade of Frohse are compared with the findings we made at the preparation of 10 recently deceased. It was especially significant, that we found in 10 of our 12 cases intraoperatively a tendinous type of arcade. In our directioned cases we encountered this type of tendinous arcade in only 2 of 10 cases. Based on these findings we are of the opinion that the tendinous arcade of Frohse is an important factor in the development of the interosseus posterior syndrome.