Objective To compare the clinical efficacy and radiologic changes between constrained and non-constrained titanium plate in anterior cervical corpectomy and fusion (ACCF) in elderly cervical spondylosis patients.Methods A total of 58 elderly cervical spondylosis patients who underwent ACCF were divided into group 1 (patients treated with constrained titanium plates,n =30) and group 2 (patients treated with non-constrained titanium plates,n=28).The Japanese Orthopedic Association (JOA) score,fusion rate,the loss of segmental height and cervical lordosis were recorded.The clinical efficacy and imaging features were compared between the two groups.Results The improvement rate of JOA score had no significant differences between group 1 and group 2 [(77.7±18.6)％ vs.(75.8±23.2)％,t=0.340,P＞0.05].At 3 months after operation,the fusion rate was higher in group 2 than in group 1 (89.3％ vs.63.3％,x2 =5.327,P＜0.05).At 3,6 and 12 months after operation,there were no significant differences in the loss of segmental cervical height and lordosis between group 1 and group 2 [(2.42±3.05)mm vs.(0.98±2.86)mm,(3.95±3.65)mm vs.(2.34±2.97)mm,(3.60±4.33)mm vs.(2.40±2.96)mm,(1.64±2.33)° vs.(0.66 ± ±2.14)°,(2.13∧±±3.79)° vs.(0.70±2.99)°,(2.39±4.26)° vs.(0.86±3.25)°,respectively,all P ＞0.05].Conclusions The clinical efficacy is similar in ACCF with the two types of titanium plates.The non-constrained titanium plate can increase the fusion rate in early time,but may aggravate the loss of segmental cervical height and lordosis,which should be used with caution in elderly osteoporosis patients.

Biological desulfurization is a process in which sulfur compounds are removed from gas and oil using microorganisms. It is a simple process that has mild operating conditions, high desulfurization efficiency, low energy consumption and less environmental pollution. However, there is still a lack of simple and efficient analytical methods for quantitatively analyzing the sulfur compounds in the biological desulfurization process. In order to solve this problem, the analytical method for the simultaneous determination of sulfite, thiosulfate and sulfide in biological desulfurization solutions by pre-column fluorescence derivation using high performance liquid chromatography (HPLC) was developed. The standard curves of sulfur species in this analytical method had good linear relationships with correlation coefficients of 0.999 5, 0.999 7, and 0.999 7 for sulfite, thiosulfate and sulfide, respectively. The detection limits of these sulfur compounds were 0.000 6, 0.000 7 and 0.001 1 μmol/L; the range of recovery rates were 98.17 to 101.9%, 100.9 to 102.6%, and 101.1 to 104.2%; which had good repeatability and stability. The analytical method was simple, efficient and accurate, and could be used to simultaneously determine the sulfur compounds in different biological desulfurization systems.
Chemistry Techniques, Analytical/methods* ; Chromatography, High Pressure Liquid ; Sulfur Compounds/analysis*

Objective: To investigate the relationships of intracranial compartment volumes with the severity of clinical symptoms before surgery, and the degree of symptom improvement one year after cerebrospinal fluid(CSF)shunt surgery in patients with idiopathic normal pressure hydrocephalus(iNPH). Methods: Twenty-one patients meeting the diagnosis criteria of international guidelines of iNPH and undergoing CSF shunt surgery in Department of Neurosurgery in our hospital from 2016 to 2017 were included.All patients underwent brain MRI measurement before surgery, and were evaluated by using 3-meter timed up and go test(TUG), minimum mental state examination(MMSE), idiopathic normal pressure hydrocephalus grading scale(iNPHGS)and modified Rankin scale(mRS)before and one year after CSF shunt procedures.The ventricular volume, brain volume, pericerebral CSF volume, total intracranial volume and Evans' index were measured in the pre-operative imaging of the brain.The following four pre-operative intracranial compartment volumes were calculated: the relative ventricular volume, brain volume ratio, pericerebral CSF volume ratio and the ratio of ventricular volume to pericerebral CSF volume. Results: The scores of gait, cognitive function and urinary function were improved after surgery in iNPH patients(all P<0.05). There were no significant difference in the correlation of intracranial compartment volumes(the relative ventricular volume, brain volume ratio, pericerebral CSF volume ratio and the ratio of ventricular volume to pericerebral CSF volume)and Evans' index with the severity of clinical symptoms including gait, cognitive function and urinary function before surgery, and with the degree of symptom improvement one year after surgery in iNPH patients(all P>0.05). There was no significant difference in intracranial compartment volumes between patients having improvement in mRS, TUG, MMSE and iNPHGS and patients having no improvement one year after surgery in iNPH patients(all P>0.05). Conclusions Patients with iNPH can benefit from CSF shunt surgery and have improvements of clinical symptoms including gait, cognitive function and urinary function.Preoperative intracranial compartment volumes(the relative ventricular volume, brain volume ratio, pericerebral CSF volume ratio and the ratio of ventricular volume to pericerebral CSF volume)and Evans' index have no correlations with the severity of clinical symptoms before surgery, and have no correlations with the degree of symptom improvement one year after surgery in iNPH patients.For this reason, preoperative intracranial compartment volumes and Evans' index cannot be used to predict whether or not CSF shunt surgery can improve specific clinical symptoms.