OBJECTIVETo find a sensitive index of early injury of the nervous system in lead-exposed workers and to provide a scientific basis for establishing an efficient occupational health surveillance route.

METHODSA total of 317 lead-exposed workers (blood lead levels: 26.90∼ 912.80 µg/L, determined with the atomic absorption spectrum) were divided into four groups according to the normal blood lead level (201 µg/L), acceptable upper limit of blood lead (400 µg/L), and diagnostic value (600 µg/L). The motor nerve conduction function was examined and analyzed by one-way ANOVA.

RESULTSThe distal latency and amplitude of the median nerve were significantly different between groups. The median distal latency of the highest blood lead group (>600 µg/L) was 3.63 ms, which was significantly longer than the average level (3.30 ms), and the median nerve amplitude of the highest blood lead group was 5.63 µV, significantly lower than the average level (7.27 µV). No significant difference was found between different groups in motor conduction velocity. Significant difference was found in ulnar nerve amplitude between groups. The ulnar nerve amplitude of the highest blood lead group was 4.31 µV, significantly lower than the average level (4.87 µV). No significant differences were observed in other parameters between groups.

CONCLUSIONThe distal latency and amplitude of the median nerve can be used as a sensitive index for the diagnosis of early subclinical motor nerve injury in lead?exposed workers.

Adult ; Humans ; Lead ; blood ; Lead Poisoning ; blood ; physiopathology ; Neural Conduction ; drug effects ; Occupational Exposure

OBJECTIVETo study the effect of captopril on the nervous function in rabbits exposed to vibration.

METHODSRabbits were divided into vibration group, intervention group, and control group. Vibration group and intervention group were exposed to (tested by) vibration. Captopril was given to intervention group from the 11th day of vibration exposure. Somatosensory evoked potential (SEP) and motor nervous conduction function (MCF) were measured and analyzed in each group before and after vibration exposure.

RESULTSThe latent periods of N1, P1 and N2 of SEP in vibration group after vibration exposure were (30.76 +/- 4.26), (41.91 +/- 6.67), and (45.29 +/- 5.81) ms respectively, and in intervention group after vibration exposure were (27.00 +/- 3.04), (35.07 +/- 4.20) and (41.15 +/- 3.19) ms respectively. Compared with intervention group before and after exposure, and control group, the latent periods of each wave of SEP were delayed significantly (P < 0.05). The nervous conduction velocity, the distant wave amplitude, and the distant potential period of sciatic nerve in vibration group after vibration exposure were significantly different from those in intervention group [(35.69 +/- 4.37) m/s, (1.55 +/- 0.73) microV, (8.16 +/- 0.71) ms respectively vs (52.20 +/- 5.13) m/s, (2.89 +/- 0.36) microV, (7.26 +/- 0.77) ms respectively (P < 0.01)].

CONCLUSIONCaptopril may improve the impairment of nervous functions to a certain degree in rabbits exposed to vibration.

Animals ; Captopril ; pharmacology ; Evoked Potentials, Somatosensory ; drug effects ; Female ; Male ; Neural Conduction ; drug effects ; Rabbits ; Sciatic Nerve ; drug effects ; physiology ; Vibration ; adverse effects

OBJECTIVETo compare the results of in vivo and in vitro in determination of the changes of allyl chloride (AC)-induced electrophysiology in rats sciatic nerve.

METHODSNinety male Wistar rats weighted 180 approximately 220 g were divided randomly into two groups, i.e. experimental group (n=40) and control group (n=50). The rats in experimental group were treated with AC dissolved in corn oil (200 mg/kg ip 3 days/week) by gavage for 12 weeks. Electrophysiological indexes of each group were determined on 3, 6, 9 and 12 weeks of AC intoxication. The indexes included measurements of sciatic nerve conduct velocity (NCV), compound action potential amplitude (CAPA), potential latency (PL), time course (TC), threshold potential (TP) and max stimulate potential (MSP).

RESULTSCompared to the corresponding time-matched control rats, on 6, 9 and 12 weeks of AC intoxication, NCV were decreased by 23.6%, 40.4% and 48.6% (P<0.05, P<0.01) in vivo, while in vitro it was decreased by 15.4% (P<0.05) on 12 week, CAPA were reduced by 31.7% in vivo, while in vitro it was reduced by 31.7%, 38.9% and 58.9% (P<0.05, P<0.01), respectively, PL were prolonged 22.6% and 40.7% (P<0.01) on 9, 12 weeks in vivo, while in vitro it was prolonged 8.0% (P<0.05), TC were increased 22.5%, 34.6% and 47.5% (P<0.01) in vivo, while in vitro it was increased 11.6%, 20.0% (P>0.05) and 19.5% (P<0.01), respectively, TP were elevated 12.1% (P>0.05), 32.3% and 40.0% (P<0.05) in vivo, while in vitro it was elevated 16.4% (P>0.05), 29.2% and 35.6% (P<0.05), respectively, MSP were increased 40.5% (P>0.05), 69.0% and 86.5% (P<0.01) in vivo, while in vitro it was increased 29.7% (P>0.05), 52.0% and 61.9% (P<0.01), respectively.

CONCLUSIONThe two methods of in vivo and in vitro showed that AC could significantly affect the electrophysiology of sciatic nerve, and the time-dependent changes occurred. The NCV is the most sensitive indicator in vivo to the early diagnosis of AC intoxication, while CAPA is the most sensitive indicator in vitro.

Action Potentials ; drug effects ; physiology ; Allyl Compounds ; poisoning ; Animals ; Disease Models, Animal ; In Vitro Techniques ; Male ; Neural Conduction ; drug effects ; physiology ; Random Allocation ; Rats ; Rats, Wistar ; Sciatic Nerve ; physiopathology

OBJECTIVETo observe the clinical efficacy of Qi-supplementing and blood-activating (QSBA) in treating diabetic peripheral nephropathy (DPN).

METHODSSixty-eight type 2 diabetes mellitus patients with Qi deficiency-blood stasis Syndrome were randomly divided into two groups, the neurotrophic agents were used in both groups, while QSBA herbs were used in the treated group additionally. The treatment course was 2 months. Blood glucose (BG), triglyceride (TG), total cholesterol (TC) and nerve conduction velocity (NCV) were detected before and after treatment.

RESULTSAfter treatment, the BG, blood lipid, NCV were improved significantly (P < 0.05) in both groups, but the improvement was more significant in the QSBA treated group than in the control group (P < 0.05).

CONCLUSIONQSBA, in treating DPN, can not only improve its symptoms, but also ameliorate the NCV.

Adult ; Aged ; Diabetic Neuropathies ; drug therapy ; Drugs, Chinese Herbal ; therapeutic use ; Female ; Humans ; Male ; Medicine, Chinese Traditional ; Middle Aged ; Neural Conduction ; drug effects ; Phytotherapy ; Qi

OBJECTIVETo explore the dose-effect relationship between 1-bromopropane (1-BP) exposure and health effects in workers.

METHODSOccupational field investigations were conducted in 1-BP factories. Ambient 1-BP concentrations were detected with detection tube, and the 8 h time-weighted average individual exposure levels (TWA-8 h) were measured by passive sampler. Workers underwent questionnaire survey, neurological examination, nerve conduction velocity examination, vibration sensation test. routine blood test as well as blood biochemical test. According to TWA values or TWA x duration values, workers were divided into three dose groups for dose-effect relationship analysis. USEPA BMDS 2.1 software was applied to calculate 1-BP benchmark dose (BMD) and its 95% lower limit (BMDL).

RESULTSThe TWA-8h concentrations ranged from 0.35 to 535.19 mg/m3 (geo-mean 14.08 mg/m3). Dose-dependent analysis showed that the motor nerve distal latency (linear regression coefficient was 0.066 6), vibration sensation of toes (linear regression coefficient were 0.157 2 and 0.193 9), creatine kinase (linear regression coefficient was -1.05) and thyroid stimulating hormone levels (linear regression coefficient was 0.1024) of 1-BP exposed workers changed in a dose-dependent manner (P < 0.05). BMD calculation based on DL as 1-BP toxic effect endpoint showed that TWA-8h of the BMD values and BMDL values were 50.55 mg/m3 and 30.78 mg/m3, respectively.

CONCLUSION1-BP causes dose-dependent changes in tibial nerve DL, vibration sensation, CK and TSH levels.

Adult ; Creatine Kinase ; blood ; Female ; Humans ; Hydrocarbons, Brominated ; analysis ; toxicity ; Maximum Tolerated Dose ; Neural Conduction ; drug effects ; Occupational Exposure ; Tibial Nerve ; physiopathology ; Workplace

OBJECTIVETo analyze the clinical characteristics of 267 cases with occupational chronic carbon disulfide (CS(2)) poisoning and to provide the basis for revising the items of periodical medical examination of workers occupationally exposed to CS(2).

METHODSThe subjects of present study were 267 patients with mild CS(2) poisoning diagnosed according to "Diagnostic Criteria of Occupational Chronic Carbon Disulfide Poisoning (GBZ4-2002)" from April in 2006 to May in 2010. All patients were from the same chemical fiber factory. When a subject was diagnosed as patient with CS(2) poisoning, who should interview with questionnaire which included the illness and occupational history, symptoms, individual habits. The physical examination, nervous test, cardiovascular test, biochemical test and electromyogram were performed.

RESULTSThe rate of decreased motor conduction velocity was 87.3% (233/267 roots). The highest detection rate of slowing conduction velocity was the common peroneal motor nerve which was 48.6% (138/248 roots) and the second was median motor nerve with delay rate of 37% (155/419 roots). The main symptoms of the patients were neurasthenia, numbness and paresthesia. The rates of abnormal achilles tendon reflex and knee jerk reflex in patients were were 79.4% and 49.8%, respectively. The detected rates of patients with ST-segment changes and hypertension were 19.1% and 27.5%, respectively. The rates of hypertension, systolic pressure and diastolic pressure were 27.3%, 22.5% and 21.1%, respectively. The rates of lactate dehydrogenase (LDH), triglycerides (TG) and low density lipoprotein (LDL) were high. The detected rates of urine acid, indirect bilirubin and total bilirubin in male patients were higher than those in female patients. In addition, the abnormal detected rate of urea nitrogen and indirect bilirubin increased with exposure years.

CONCLUSIONOccupational chronic CS(2) poisoning mainly affects the nervous system, as well as liver and kidney function. Detecting the median and common peroneal motor nerve conduction velocities could be the screening indicators for the peripheral nerve injury induced by CS(2) in the occupational exposure population during the periodical occupational medical examinations.

Adult ; Aged ; Carbon Disulfide ; poisoning ; Chemical Industry ; Female ; Humans ; Kidney ; drug effects ; physiopathology ; Liver ; drug effects ; physiopathology ; Male ; Middle Aged ; Multiphasic Screening ; Nervous System ; drug effects ; physiopathology ; Neural Conduction ; Occupational Exposure

OBJECTIVETo investigate the health effects of 1-bromopropane (1-BP) on female exposed workers.

METHODSFour 1-BP manufacturing plants were investigated. Workers were interviewed with questionnaire and examined with neurobehavioral core test battery, nerve conduction velocity tests of nervus tibialis and nervus suralis, vibration sensation test, hematological and biochemical tests. Ambient 1-BP concentration was measured with detection tube, and time-weighed average levels of individual workers were estimated with passive samplers.

RESULTS1-BP concentration in the plants ranged from 0 to 402.40 mg/m3 (Geomean 32.19 mg/m3). Time-weighted average exposure levels (TWA-8 h) ranged from 0.35 to 535.19 mg/m3 (Geomean 14.08 mg/m3). Compared with the control group, 1-BP exposed workers showed reduced motor nerve conduction velocity [(44.8 +/- 8.7) m/s] and sensory nerve conduction velocity [(45.5 +/- 4.9) m/s], prolonged distal latency [(7.5 +/- 2.1) ms], reduced toe vibration perception, and altered neurobehavior parameters(POMS vigor, tension, anxiety, confusion) significantly (P < 0.05). As to hematological and biochemical indicators, the exposed workers showed decreased white blood cell count [(5.6 +/- 2.17) x 10(3)/microl], red blood cell count [(3.9 +/- 0.4) x 10(6)/microl], hemoglobin [(121.1 +/- 14.5) g/L] and creatine kinase [(82.0 +/- 27.5) IU/L] (P < 0.05), and increased serum total protein (8.0 +/- 0.5 g/dl), lactate dehydrogenase [(335.2 +/- 356.6) IU/L], thyroid-stimulating hormone [(3.6 +/- 2.3) microIU/ml] and follicle-stimulating hormone levels (18.7 +/- 24.4 mIU/ml) (P < 0.05).

CONCLUSION1-BP exposure may affect peripheral nerves and central nervous system, and lead to abnormal hematological and biomedical indicators.

Adult ; Creatine Kinase ; metabolism ; Female ; Hematologic Tests ; Hemoglobins ; metabolism ; Humans ; Hydrocarbons, Brominated ; adverse effects ; Middle Aged ; Nervous System ; drug effects ; physiopathology ; Neural Conduction ; drug effects ; Occupational Exposure ; Young Adult

OBJECTIVETo observe preventive and therapeutic effects of Tanshinone IIA (T II A) on oxaliplatin induced peripheral neuropathy (OlPN) and to explore its effects on the expression of calcitonin gene related peptide (CGRP) and never growth factor (NGF).

METHODSTotally 36 phase II - III patients with malignant tumor of digestive tract undergoing chemotherapy program with oxaliplatin, were equally assigned to the T II A group (using THA at 80 mg/day 1 day before oxaliplatin chemotherapy for 3 successive days) and the control group (using chemotherapy program with oxaliplatin alone) by segmented randomization. After 4 cycles of chemotherapy, the incidence degree and incidence of OlPN were evaluated. Sensory nerve conduction velocity (SNCV) and motor nerve conduction velocity ( MNCV) were tested by EMG evoked potential device. Serum levels of CGRP and NGF were also detected in the two groups before and after chemotherapy. The correlation of serum levels of CGRP and NGF to OIPN was assessed using linear correlation analysis.

RESULTSAfter chemotherapy the OlPN incidence was 27.8% (5/18 cases) in the T II A group, obviously lower than that in the control group (55.6%, 10/18 cases; P < 0.05). Compared with before treatment in the same group, SNCV and MNCV of common peroneal nerve were slowed down, serum NGF levels decreased, and serum CGRP levels obviously increased in the two groups (all P < 0.05). Compared with the control group after treatment, SNCV and MNCV of common peroneal nerve were obviously accelerated, serum NGF levels increased, and serum CGRP levels obviously decreased in the THA group (all P < 0.05). Results of linear correlation analysis indicated serum NGF level was negatively correlated with peripheral neuropathy (PN), serum CGRP expression was positively correlated with neurotoxicity (P < 0.05).

CONCLUSIONT II A could reduce the incidence of OlPN, which might be associated with inhibiting the expression of CGRP and up-regulating NGF activities.

Calcitonin Gene-Related Peptide ; blood ; Diterpenes, Abietane ; therapeutic use ; Gastrointestinal Neoplasms ; drug therapy ; Humans ; Nerve Growth Factor ; blood ; Neural Conduction ; drug effects ; Organoplatinum Compounds ; adverse effects ; Peripheral Nervous System Diseases ; chemically induced ; drug therapy ; Up-Regulation

OBJECTIVETo explore the dose-effect relationship between lead exposure and nerve conduction velocity, and to assess risk characteristics of nerve conduction velocity induced by lead exposure.

METHODSThe external dose, internal dose (blood lead, urine lead) and the conduction velocity of peripheral nerve were examined. The benchmark dose of a population exposed to occupational lead was estimated to develop risk assessment of nerve conduction velocity in worker exposed to lead by use of BMDS (version 1.3.3). The BMDL in terms of blood lead and urine lead was calculated.

RESULTSThere was correlation between blood lead and urine lead. The sense nerve conduction velocity was decreased significantly in the group of lead exposure workers (P < 0.05). The BMDLs-05 for median nerve conduct velocity, ulnar nerve conduction velocity, and superficial peroneal nerve conduction velocity in terms of blood lead were 456.99, 332.36 and 468.38 microg/L respectively; the BMDLs-05 in terms of urine lead were 14.1, 9.2 and 13.6 microg/gCr respectively.

CONCLUSIONThe internal dose is the better index to reflect the level of lead exposure. Blood lead is identified as a specific and sensitive biomarker for sense nerve conduction velocity reduction. Ulnar nerve conduction velocity can be used as highly sensitive biomarkers to screen the high risk population of lead exposure.

Adolescent ; Adult ; Aged ; Biomarkers ; blood ; Female ; Humans ; Lead ; adverse effects ; blood ; Lead Poisoning ; blood ; Male ; Middle Aged ; Neural Conduction ; drug effects ; Occupational Exposure ; Risk Assessment ; Surveys and Questionnaires ; Young Adult

Traditional Chinese medicine has certain effects on diabetic peripheral neuropathy and predominates in the integral medication of multi-factorial, multi-target action, et al. In this paper, the experimental studies concerning the effects of Chinese compound recipes on diabetic peripheral neuropathy in recent 6 years are reviewed in respect of the polyalcohol pathway and related metabolic disorder, the activation of protein kinase C, the formation of advanced glycation endoproducts, oxidative stress, neurotrophy factors, haemodynamics and blood vessel factors. It analyzes the existing problems and looks into the future research in this domain as well.
Animals ; Diabetic Neuropathies ; drug therapy ; metabolism ; physiopathology ; Drugs, Chinese Herbal ; isolation & purification ; therapeutic use ; Enzyme Activation ; drug effects ; Hemodynamics ; drug effects ; Medicine, Chinese Traditional ; methods ; trends ; Neural Conduction ; drug effects ; Oxidative Stress ; drug effects ; Phytotherapy ; methods ; trends ; Protein Kinase C ; metabolism