[Revision rate of periprosthetic joint infection post total hip or knee arthroplasty of 34 hospitals in China between 2015 and 2017: a multi-center survey].

Objective: To investigate the rate of periprosthetic joint infection (PJI) revision surgeries and clinical information of hip-/knee- PJI cases nationwide from 2015 to 2017 in China. Methods: An epidemiological investigation. A self-designed questionnaire and convenience sampling were used to survey 41 regional joint replacement centers nationwide from November 2018 to December 2019 in China. The PJI was diagnosed according to the Musculoskeletal Infection Association criteria. Data of PJI patients were obtained by searching the inpatient database of each hospital. Questionnaire entries were extracted from the clinical records by specialist. Then the differences in rate of PJI revision surgery between hip- and knee- PJI revision cases were calculated and compared. Results: Total of 36 hospitals (87.8%) nationwide reported data on 99 791 hip and knee arthroplasties performed from 2015 to 2017, with 946 revisions due to PJI (0.96%). The overall hip-PJI revision rate was 0.99% (481/48 574), and it was 0.97% (135/13 963), 0.97% (153/15 730) and 1.07% (193/17 881) in of 2015, 2016, 2017, respectively. The overall knee-PJI revision rate was 0.91% (465/51 271), and it was 0.90% (131/14 650), 0.88% (155/17 693) and 0.94% (179/18 982) in 2015, 2016, 2017, respectively. Heilongjiang (2.2%, 40/1 805), Fujian (2.2%, 45/2 017), Jiangsu (2.1%, 85/3 899), Gansu (2.1%, 29/1 377), Chongqing (1.8%, 64/3 523) reported relatively high revision rates. Conclusions: The overall PJI revision rate in 34 hospitals nationwide from 2015 to 2017 is 0.96%. The hip-PJI revision rate is slightly higher than that in the knee-PJI. There are differences in revision rates among hospitals in different regions.

[Role of personalized 3D printing in brain protection after decompressive craniectomy].

Objective: To explore the application value of personalized three-dimensional (3D) printed protective cap in brain protection after decompressive craniectomy (DC). Methods: Fourty-five patients who underwent DC from January 2021 to October 2021 were selected, including 26 males and 19 females, aged 5-73 (50±13) years old. The brain CT data were imported into 3D Slicer software to rebuild the protective cap through 3D printing. The cap was worn on the head of the patient, thereby preventing secondary braindamage. The follow-up results were compared with 53 patients without protective capduring the same period. Results: There were no statistically significant differences in age, skull defect location and follow-up time between the two groups (all P>0.05).Among 45 patients, 47 brain protective caps (2 cases with bilateral skull defects) were successfully designed. The time for image post-processingand 3D printing was (21.2±6.0) min and (62.4±8.3) min, respectively. There were 6 cases of low compliance, 9 cases of moderate compliance, 32 cases of high compliance, respectively. Six cases with low conformity were redesigned and printed, 2 of 9 cases with moderate conformity were redesigned and printed, and the remaining 7 cases reached high compliance after grinding and packaging. In the current study, 45 patients with brain protective caps were followed up for 3 months, and no secondary brain injury occurred. However, among 53 patients without brain protective caps during the same period, 4 patients had secondary accidental brain compression. The incidence of injury was 7.5 %, and the difference was statistically significant (P<0.001). Conclusion: Brain protective cap designed based on cranial CT and 3D printing can be used in patients with skull defects to protect the brain tissue from secondary crush damage and has certain clinical value.

[Clinical application analysis of a method for locating scalp projection of intracranial lesions based on neuroimaging].

Objective: To explore the feasibility of a method based on neuroimaging and surface markers for locating scalp projection of intracranial lesions. Methods: The clinical data of 46 patients who were used 'double-circle method' for locating scalp projection of intracranial lesions at Department of Neurosurgery,the First Affiliated Hospital of Xiamen University from January to June 2021 were retrospective analyzed. All patients with 2 electrodes(artificial fiducials) randomly attached to scalp had been examed thin-layer brain CT. The distances from the center of each fiducial to the root of the nose and tragus were measured through the images. A compass was used to draw two arcs with the root of nose and the tragus as the center and the pre-measured distance as the radius on patient's scalp. Then two arcs' intersection on the scalp was the fiducial. The method was named 'double-circle method'. Two neurosurgeons were arranged to perform fiducial identification with double-circle method, and record the error between the result and the actual fiducial point.Independent sample t test was used for data comparison, and Kappa test was used to analysis the inter-group consistency. Results: Ninety-two fiducial points of 46 patients were collected. Time consuming of doctor A was (8.1±2.3) minutes(range:5 to 15 minutes)and doctor B was (8.9±3.5) minutes(range:4 to 17 minutes).The positioning error from the doctor A was (4.4±2.4)mm(range:0 to 12 mm) and doctor B was(4.2±2.6) mm(range:0 to 14 mm)(t=-0.575,P=0.567),the difference was not statistically significant. The Kappa value of the consistency test of error between two doctors was 0.517(P=0.001).The consistency was moderate.Eight patients used 'double-circle method' and neuronavigation for locating scalp projection of intracranial lesions at the same time. The diameter of the lesions was (3.8±0.9)cm (range: 2.6 to 5.1 cm), and the positioning error of the 'double-circle method' and navigation was (4.0±1.9) mm(range: 1 to 6 mm), and all patients were confirmed to be accurately located during surgery. Conclusion: 'Double-circle method' is a simple,convenient and accurate way in locating intracranial lesions and has certain clinical significance.

Neuroprotective effect of gastrodin in methamphetamine-induced apoptosis through regulating cAMP/PKA/CREB pathway in cortical neuron.

OBJECTIVE: Methamphetamine (MA) abuse induces neurotoxicity and causes neuronal cell apoptosis. Gastrodin is a traditional Chinese herbal medicine used for the treatment of nerve injuries, spinal cord injuries, and some central nervous system diseases as well. The present study investigated the neuroprotective effects of gastrodin against MA-induced neurotoxicity in neuronal cells and its potential protective mechanism. METHODS: The primary cortex neuronal culture was divided into four groups (control group, MA group, MA + gastrodin group, and MA + gastrodin + small interfering RNA group). The neurotoxicity of MA was assessed by detecting apoptotic cells by terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick-end labeling assay and cell viability by cell counting kit 8 (CCK-8) method, the Tuj1-positive cells and the average axonal length were detected by immunofluorescence, and the expressions of cyclic adenosine monophosphate (cAMP), protein kinase A (PKA), cAMP-response element-binding (CREB), and brain-derived neurotrophic factor (BDNF) proteins were detected by Western blot. RESULTS: The results of CCK-8 assay showed that 0.5 mM MA was an optimal concentration that induced neurotoxicity (p < 0.01). Pretreatment with 25 mg/L gastrodin exerted maximum protective effects on neuronal cells. The expression levels of cAMP, PKA, phosphorylated PKA, CREB, phosphorylated CREB, and BDNF proteins were decreased in the MA group, and pretreatment with gastrodin upregulated the expression levels of these proteins (p < 0.01). The expressions of PKA and CREB proteins showed no significant changes in the control group, MA group, and gastrodin group. Compared the MA + gastrodin + small interfering RNA group with MA + gastrodin group, the Tuj1-positive cells and the average axonal length were decreased significantly, while the number of apoptotic cells was increased (p < 0.05). CONCLUSION: Gastrodin has neuroprotective effects against MA-induced neurotoxicity, which exerts neuroprotective effects via regulation of cAMP/PKA/CREB signaling pathway and upregulates the expression of BDNF.

[Pathogenesis of piriformis syndrome: a magnetic resonance imaging-based comparison study].

Objective: To assess the morphological parameters of the piriformis muscle through magnetic resonance imaging(MRI) so as to further elucidate the pathogenesis of piriformis syndrome (PS). Methods: From September 2015 to October 2016, 30 suspected PS patients and 30 normal controls were enrolled in this study from the Nanfang Hospital, Southern Medical University. The possible causative factors of the PS in the patients were obtained, and the PS patients were divided into subgroups according to the anatomic site of the tender regions. The parameters of the maximum thickness (cm), area (cm(2)) and the volume (cm(3)) of the piriformis muscle of both groups were measured by MRI and were statistically compared between the groups with the independent-sample t test so as to investigate the pathogenesis of injured sciatic nerve. Results: Twenty-six patients were verified with PS, unhealthy sitting postures presented in 16 patients (61.5%) and no trauma history was recorded in these patients. Fifteen cases (57.7%) with tenderness located at the suprapiriformis foramen region (SPF group, n=15), 11 patients (42.3%) with tenderness at the piriformis muscle (PM group, n=11). The thickness, area and volume of the pathological side piriformis muscle in the PM group were all significantly higher than the corresponding indexes in the control group[(2.24±0.46) vs (1.66±0.30) cm, (14.4±2.2) vs (8.8±2.1) cm(2,) (23.9±3.8) vs (15.2±2.6) cm(3,) respectively, t=4.699, 7.437, 8.291, all P<0.05]and were all higher remarkably than those in the SPF group[(1.62±0.20) cm, (8.7±1.6) cm(2,) (14.1±4.8) cm(3,) respectively, t=4.640, 7.631, 5.589, all P<0.05]. No significant difference was observed in the up-mentioned indexes between the SPF and the control group (t=-0.439, -0.102, -1.083, all P>0.05). Conclusions: Tender region at the buttock indicates the lesion site in the PS patients. The PS patients with tenderness at the suprapiriformis region might originate from another pathogenesis independent of piriformis muscle compression, the injury of the sciatic nerve or its branch maybe due to the indirect crush by the soft tissue of the suprapiriformis region under an unhealthy sitting posture.

Angiopoietin-2 inhibits the growth of tongue carcinoma without affecting expression of vascular endothelial growth factor.

Angiopoietin-2 (Ang-2) has been identified as an important factor in tumour angiogenesis through its action in blocking the stabilizing actions of Ang-2 and leading to new tumour vessel growth in the presence of vascular endothelial growth factor (VEGF). In the authors' previous study, over-expression of Ang-2 in Tca8113 tongue tumour cells inhibited growth. The current study aims to clarify the mechanisms of Ang-2-mediated tumour growth inhibition and its role in the regulation of VEGF expression. These studies used tumours derived from Ang-2-transfected Tca8113 cells injected into nude mice. The results showed that Ang-2-transfected tumours displayed aberrant angiogenic vessels with few associated smooth muscle cells. No detectable differences in VEGF expression were observed between Ang-2-transfected and parental tumours. Tumours produced by the Ang-2 transfection also had a higher apoptosis index and lower tumour cell proliferative index than tumours in the control groups. These observations suggest that enhanced expression of Ang-2 has no effect on VEGF expression and results in tumour vessel regression and inhibition of tumour growth.

Growth of compound single- and multi-walled carbon nanotubes.

Single-walled carbon nanotubes (SWCNTs) and multi-walled carbon nanotubes (MWCNTs) are complement to each other in many of their physical properties. We report the synthesis of carbon nanotube cables-a form of compound single- and multi-walled carbon nanotubes which could have the superior properties of both the SWCNTs and MWCNTs. This compound form of carbon nanotubes consists of a bundle of SWCNTs formed into a MWCNT, and the diameter of the inner most shell of the MWCNT ranges from a few to tens nanometers. The growth of these compound carbon nanotubes cannot be explained readily via existing modes of carbon nanotube growth, but promises a new way for improving and controlling the physical properties of either single- or multi-walled carbon nanotubes.

[Studies on the recurrent attacks of acute adenolymphangitis due to Malayan filariasis].

OBJECTIVE: To explore the role of filarial and bacterial infections in the recurrent attacks of acute adenolymphangitis due to malayan fialriasis. METHODS: 1. To observe the seasonal fluctuation of acute attacks by performing monthly follow-up on patients with history of acute attacks in recent years. 2. To study the relationship between bacterial infection and filarial adenolymphangitis by performing bacteria culture and anti-streptolysin O test. 3. To investigate the variation of acute attacks by controlling filariasis transmission or by treating patients with a history of recurrent acute attacks. RESULTS: 1. The peak of acute attacks in patients coincided with the peak of vector transmission season. 2. Of the 97 cases examined by bacteria culture, 90 cases were negative; of the 255 cases examined by anti-streptolysin O test, the titres in 94.1% (143/152) of the cases with first attack and simple adenolymphangitis were within normal limits, however, the titres in 27.2% (28/103) of the cases complicated with elephantiasis were increased. 3. The acute attack rate of adenolymphangitis per year reduced significantly in cases with first attack and simple adenolymphangitis after effective control of filariasis transmission. 4. There was no evidence of the reduction of acute attacks by treating patients with DEC alone. CONCLUSION: In malayan filariasis endemic areas, the main causes of recurrent attacks of acute adenolymphangitis might be the repeated filarial infections due to the persistence of filariasis transmission.

(C70)2-p-tert-butylcalix[6]arene complex films on electrodes catalyze the reduction of nitrite ions.

(C70)(2)-p-tert-butylcalix[6]arene complex films on GC electrode surface showed two couples of redox reactions in mixed solvent of (1:1, v:v) acetonitrile and water containing tetra-butylammonium perchlorate. The electrocatalytic reduction for nitrite by these films was observed, indicating that (C70)(2)-p-tert-butylcalix[6]arene is capable of mediating the electron transfer to nitrite.

[Study on the transmission threshold of filariasis. Collaborating Research Group on the Transmission Threshold of Filariasis].

Twenty-one villages from ten provinces and one autonomous region with different mf rates in population and different levels of mean mf density per 60 microliters blood in positive cases and representative species of filaria and vector after DEC treatment were selected as study sites. In these villages a longitudinal investigation for a period of 3-5 years was carried out without adopting any control measure. The main results were: 1. Among 279 residual microfilaremia cases, 235 (84.2%) turned negative spontaneously and successively. The negative conversion rates were 86.6% (46/53) in malayan cases, 60.8% (28/46) in bancroftian cases after 3 years' follow-up, and 100% (29/29) in malayan cases, 87.4% (132/151) in bancroftian cases after 4-5 year's follow-up. Among 110 bancroftian cases followed-up to seven years, 109 (99.1%) turned negative. 2. Twenty-two new microfilaremia cases were detected, of which, 18 might be missed in previous blood examination, 4 might be new infection. 3. Mf rate in the population in twenty villages has been trending down, whereas in one village fluctuated around the original level. Among the 20 villages, no microfilaremia case was found in 7 villages. 4. The natural infection rates of filarial larvae and infective rates in mosquito vectors were in descending trend in most of these villages, and no filarial larva was found in 12 villages.(ABSTRACT TRUNCATED AT 250 WORDS)

Rheological properties of the extracellular polysaccharide from Agrobacterium sp.S-1231.

A strain of Agrobacterium sp. S-1231 was isolated from one of the soil samples taken from Beijing area. In 4 days' cultivation it was found to produce extracellular polysaccharide and about 24 grams per liter of sugar-containing substrate. At the same concentrations, the polymer produced higher viscosity than that of xanthan gum (Kelzan). The viscosities of 0.2%, 0.5% and 1.0% solutions of this polymer were found to be 840, 5200 and 15000 cp respectively, measured with a Brookfield LVF viscosimeter at 6 rpm. Besides its pseudoplastic rheological properties and the excellent stability towards pH, it had unusual compatibility with high levels of salts and provided shear thinning properties similar to that in fresh water. Moreover, it is also compatible with cationic dyes without precipitation. Unlike other microbial polysaccharides, the viscosities of this polymer remained constant at different temperatures under 65 degrees C, but it decreased sharply in a narrow range of temperatures between 70-75 degrees C.

Assessment of intradermal test in longitudinal surveillance of bancroftian filariasis.

Longitudinal surveillance was carried out consecutively during 1982-1987 in two pilot villages where bancroftian filariasis was prevalent in different severity before 1982. Intradermal test (IT) with filaria polypeptide (FPT) antigen prepared from Dirofilaria immitis was made. It was shown that the level of immediate hypersensitivity reaction to the antigen in population as shown by IT appeared to be directly proportional to both the prevalence of the disease and the infection rate of mosquitoes harbouring larval filariae before mass and selective treatment with diethylcarbamazine. Time for negative conversion of IT after chemotherapy was significantly longer in previous microfilaraemic patients than that in amicrofilaraemic cases. The selected three criteria of IT used in filariasis surveillance, namely, the positive rate, frequency of strong reaction and positive conversion rate, were diminished gradually after chemotherapy year by year, so that the three criteria were demonstrated to be useful for longitudinal surveillance of lymphatic filariasis.

A field survey on the role of low-density microfilaraemia cases in the transmission of filariasis.

In former filariasis endemic areas, where the disease has been basically controlled, a few cases of low-density microfilaraemia remain. A survey was carried out in Deqing County, Zhejiang Province, from September 1981 to 1986 in order to determine whether such cases play a role in the continuation of transmission. The results of parasitological and entomological investigations for two consecutive years revealed that after the implementation of intervention measures, the mean microfilaraemia rate in the population fell to about 0.5% and the mean microfilaria density to about 4.2 mf/60 microliter of blood in previously endemic areas of malayan filariasis. Although there were considerable numbers of An. sinensis biting humans, infective larvae could be found in only two positive mosquitoes out of 5,484 dissected, and no new microfilaraemic cases were detected in the 1983 and 1986 follow-up blood examinations, indicating that transmission had already been interrupted. Two volunteers with a microfilaraemia of 3-5 mf/60 microliter of blood were exposed to two batches of An. sinesis in August 1981. The engorged mosquitoes were dissected eight days later. Even though the infection rate of An. sinensis having fed on low-density microfilaraemic cases was as high as 16.8%, the intensity of infection was extremely low, being 1.1 mf/mosquito. From the transmission dynamics point of view, infected mosquitoes carrying very few infective larvae have no practical significance in the transmission of filariasis. It is suggested that the treatment of persons with low-density microfilaraemia (with 5 mf/60 microliters of blood) in areas with low microfilaria rates (less than 1%) need not to be considered as essential.

[Assessment of intracutaneous test in longitudinal surveillance for lymphatic filariasis].

In order to evaluate the usefulness of intracutaneous test (IT) in longitudinal surveillance of filariasis, two administrative villages selected from Queshan County, Henan Province of China, endemic for Wuchereria bancrofti, were surveyed in 1982, 1983 and 1987 respectively, by IT with antigen FPT derived from Dirofilaria immitis. The result showed that the original level of IT to antigen FPT in the population was consistent with the data of either etiological or entomological investigation before chemotherapy. When the microfilaraemia rate and natural filarial infection rate of mosquitoes in a village were high, the positive rate and frequency of strong positivity (skin wheel diameter greater than or equal to 1.3 mm) for immediate hypersensitivity reaction would be high too; and the reverse was true. It is suggested that both criteria of IT mentioned above may be useful in assessing endemicity of lymphatic filariasis before mass chemotherapy. The speed of negative conversion of IT in both groups, the previously microfilaraemic patients and the microfilaraemic inhabitants positive to immediate hypersensitivity reaction before chemotherapy, were different, the former being significantly slower than that of the latter after mass and selective chemotherapy with diethylcarbamazine. All of the three criteria for immediate hypersensitivity, positive rate, frequency of strong positivity and positive conversion rate, decreased gradually after a mass and selective DEC treatment. Until 1987, the 5th year after the chemotherapy, the average positive rate in the two villages dropped to 20.0% from 55.4% in 1982, the frequency of strong positivity to 2.8% from 23.8% in 1982, and the positive conversion rate to 9.7% (1984-1987) form 19.2% (1982-1983).(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical trial on furapyrimidone in filariasis.

A clinical trial was carried out with furapyrimidone in treating 51 patients with B. malayi, 159 with W. bancrofti and eight with D. perstans using different dosage schedules. Two hundred and fifty-seven cases of Malayan and bancroftian filariasis were treated with hetrazan for comparison. The results based on the microfilaricidal effects suggest that furapyrimidone possesses similar therapeutic effects of hetrazan on Malayan filariasis at eight-month follow-up, and higher incidences of microfilarial disappearance of W. bancrofti infection (81.3%) at six-month follow-up. The drug was also effective against D. perstans. The side effects consisted of fever and irritation of the digestive tract. Fever may be related to allergic reaction of foreign protein from the dead or dying parasites. The side reactions are similar to those of hetrazan and usually not serious. Comparing the efficacies and side effects of furapyrimidone with different dosage schedules the authors recommend regimens of 15 to 20 mg/kg/day for six days in treating Malayan filariasis and 20 mg/kg/day for seven days in treating bancroftian filariasis.