Users' cognition and information retrieval are faced with great challenges in ubiquitous knowledge environ-ment. The influence of cognitive factors such as personality traits, cognitive style and ability, knowledge structure and ascribed methods on users' information retrieval behaviors was thus analyzed. It was pointed out that different cognitive factors could influence the retrieval, judgment and absorption of its results,users' satisfaction and continuous use in ubiquitous knowledge environment,with suggestions put forward from the aspects of information retrieval education, information service and information users for improving the users ' knowledge system in knowledge assimilating process by working out effective retrieval strategies using the advantages of cognition.

Objective The purpose of the present study is to illustrate the effect of olfactory ensheathing cells(OECs) on the survival and neurite outgrowth of GABAergic neurons in vitro. Methods OECs were dissociated from olfactory bulb and neurons from spinal cord of E12 mouse. On the sixth day in vitro,the Millipore cultue blank with OECs was transferred to the neuron culture mediam and continue the co-culture for another 6 days.The cultured neurons were stained with anti-GABA antibody.The neurite of neurons was observed with an image system.The number of GABAergic positive neurons was counted under the microscope. Result The number of GABAergic neurons was 39^7?6^3 in co-culture groups,whereas the number of GABAergic neurons represented only 27^6?2^7 in control groups(CG),(P

OBJECTIVETo study the impact of the chloride channel dysfunction of the cystic fibrosis transmembrane conductance regulator (CFTR) on the cytoskeleton of Sertoli cells in the mouse.

METHODSTM4 Sertoli cells were cultured and treated with CFTR(inh)-172 at the concentrations of 1, 5, 10 and 20 μmol/L for 48 hours. Then the cytotoxicity of CFT(inh)-172 was assessed by CCK-8 assay, the expressions of F-actin and Ac-tub in the TM4 Sertoli cells detected by immunofluorescence assay, and those of N-cadherin, vimentin and vinculin determined by qPCR.

RESULTSCFTR(inh)-172 produced cytotoxicity to the TM4 Sertoli cells at the concentration of 20 μmol/L. The expressions of F-actin and Ac-tub were decreased gradually in the TM4 Sertoli cells with the prolonging of treatment time and increasing concentration of CFTR(inh)-172 (P < 0.05). The results of qPCR showed that different concentrations of CFTR(inh)-172 worked no significant influence on the mRNA expressions of N-cadherin, vimentin and vinculin in the Sertoli cells.

CONCLUSIONThe CFTR chloride channel plays an important role in maintaining the normal cytoskeleton of Sertoli cells. The reduced function and expression of the CFTR chloride channel may affect the function of Sertoli cells and consequently spermatogenesis of the testis.

Actins ; metabolism ; Animals ; Benzoates ; pharmacology ; Chloride Channels ; physiology ; Cystic Fibrosis Transmembrane Conductance Regulator ; antagonists & inhibitors ; Cytoskeleton ; drug effects ; Male ; Mice ; Sertoli Cells ; drug effects ; metabolism ; Spermatogenesis ; Thiazolidines ; pharmacology ; Time Factors

OBJECTIVETesticular mixed nonseminomatous germ cell cancer (TMNGCC) is rarely reported. This study aimed to explore the clinical symptoms, pathological characteristics and treatment methods of TMNGCC.

METHODSWe analyzed the clinical data of 1 case of TMNGCC, observed its pathological characteristics under the light microscope by histology, cytochemistry, immunohistochemistry and immune marking, and investigated the clinical features of such tumors by reviewing the relevant literature.

RESULTSThe patient presented with a chief complaint of painless testicular swelling for 3 years. Histopathological examinations revealed a tumor of papillary, fissural or adenoid structure, with large polygonal or columnar cells with one or more irregular vesicular nuclei, the nuclear membrane clear, the cytoplasm eosinophilic or basophilic, and the interstitium infiltrated by a few lymphocytes. Here are the immunohistochemical results: CD117 -, CK8-18 + +, CD30 + +, CK + + +, vimentin -, PLAP +/-, P53 +, AFP + and EMA + +. The tumor was pathologically diagnosed as teratogenic embryonic testicular cancer, and treated by radical surgery, followed by adjuvant chemotherapy according to the treatment of TMNGCC. One-year follow-up found the patient to be alive.

CONCLUSIONTMNGCC is a rare malignant tumor, mostly with unobvious clinical symptoms. Its diagnosis primarily depends on physical examination, ultrasonography, CT, and measurement of serum tumor markers; its confirmation necessitates pathological examination, and its first-choice treatment is surgical resection.

Adult ; Humans ; Male ; Neoplasm Staging ; Seminoma ; pathology ; Testicular Neoplasms ; pathology

BACKGROUND AND OBJECTIVELetrozole is an aromatase inhibitor that is used in the treatment of estrogen-sensitive tumors such as endometrial carcinoma, however, its therapeutic effect is still to be further improved. It is reported that curcumin has antitumor capability and can enhance the sensitivity of tumor cells to anticancer agents. This study was to investigate the inhibitory effect of letrozole combination with curcumin on the implanted endometrial tumor growth.

METHODSNude mice were implanted with endometrial carcinoma RL-952 cells. All tumor-bearing mice were randomly divided into 5 groups: control(without treatment), Let(1) (letrozole, 1 microg/d), Let(10) (letrozole, 10 microg/d), Cur [ curcumin, 300 mg/kg.d)], and Let + Cur group [10microg/d letrozole + 50mg/ (kg.d) curcumin]. The tumor growth was monitored. Tumor cells apoptosis was detected in both control and treated groups. The expressions of bcl-2 mRNA and bcl-2 protein were detected using RT-PCR and Western blot, respectively.

RESULTSFifty mice were successfully implanted with the endometrial tumor. Treatment with letrozole markedly inhibited tumor growth; the inhibitory effect was further enhanced by the combination of letrozole and curcumin. The inhibitory rates in Let (1), Let (10), the Cur, and the Let + Cur groups were 15.95%, 22.49%, 21.57%, and 35.89%, respectively. Treatment with curcumin inhibited the expression of bcl-2 in tumor cells at the mRNA and protein levels. The apoptosis rates in the control group and the four experimental groups mentioned above were 16.97%, 32.90%, 35.80%, 34.16%, and 47.24%, respectively. Tumor cells apoptosis were observed in mice treated with either letrozole or curcumin; however, combination of letrozole and curcumin further enhanced the inhibitory rate in tumor growth.

CONCLUSIONSTreatment with letrozole or curcumin could inhibit the xenografted endometrial tumor growth by inducing apoptosis in tumor cells. Combination of letrozole and curcumin further enhanced the inhibitory effect of tumor growth.

Adenocarcinoma ; metabolism ; pathology ; Animals ; Apoptosis ; drug effects ; Cell Cycle ; drug effects ; Cell Line, Tumor ; Curcumin ; administration & dosage ; pharmacology ; Drug Synergism ; Endometrial Neoplasms ; metabolism ; pathology ; Female ; Humans ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Neoplasm Transplantation ; Nitriles ; administration & dosage ; pharmacology ; Proto-Oncogene Proteins c-bcl-2 ; genetics ; metabolism ; RNA, Messenger ; metabolism ; Random Allocation ; Receptors, Estrogen ; metabolism ; Triazoles ; administration & dosage ; pharmacology ; Tumor Burden ; drug effects ; Xenograft Model Antitumor Assays

Objective To observe the effect of variable frequency vibration therapy while sitting in an anti-spasmodic posture on spasticity and the motor function of the upper limbs among stroke survivors.Methods Thirty stroke survivors with upper limb spasticity were randomly divided into a treatment group and a control group,each of 15.Both groups were given routine rehabilitation training for 4 weeks while the treatment group was additionally provided with variable frequency vibration training while sitting in anti-spasmodic postures.Before and after the treatment,the modified Ashworth scale (MAS) was used to assess spasticity.The root mean square (RMS) value of the surface electromyogram amplitude of the affected biceps when extended passively and those of the triceps,obliques and multifidus in maximum isometric contraction was measured and recorded.The motor function of the affected upper limbs was evaluated using the active range of motion (A-ROM) of the shoulder,elbow and wrist,as well as a Fugl-Meyer assessment (FMA).Moreover,ability in the activities of daily living (ADL) was assessed using the modified Barthel index (MBI).Results After the treatment,significant improvement was observed in the average MAS,A-ROM,RMS,FMA and MBI results in both groups compared to those before the treatment.Moreover,the results in the treatment group were significantly better than those of the control group,on average.Conclusions Variable frequency vibration therapy while sitting in an anti-spasmodic posture combined with traditional rehabilitation is more effective than the latter alone in relieving spasticity as well as improving motor function and ability in the activities of daily living among stroke survivors with the upper limb spasticity.

Objective To explore the setup error and area registration error during lung cancer radiotherapy by using the on board imager (OBI) of the linear accelerator. Methods Totally 50 lung cancer patients underwent image-guided radiation therapy. Then OBI system was used for the scan validation by electronic portal imaging device (EPID) and cone beam CT (CBCT), and comparative analysis was executed on the setup errors of EPID and CBCT. Results The translation errors of EPID were (-1.62 ±1.58), (2.12 ±1.49) and (4.52 ±2.42)mm respectively at Lat, Vrt and Lng directions, while those of CBCT were (-1.27±1.25), (1.43±1.57) and (3.12±2.62) mm respectively. The registration errors at Lat, Vrt and Lng directions and rotation angle of lung tissue were (-1.27±1.25), (1.43±1.57), (3.12±2.62)mm and (0.5±1.6)° respectively, and those of target area were (-1.56±1.78), (1.68±2.39), (3.42±2.73)mm and (0.8±1.9)° respectively. CBCT and EPID had statistical differences (P<0.05) in setup error validation as well as setup errors at Vrt and Lng directions. There were no significant differences (P>0.05) when CBCT self-registration was involved in selecting different areas. Conclusion CBCT and EPID can both used for the setup validation of lung cancer, while the former behaved better than the latter.

In the face of the worldwide threat of severe acute respiratory syndrome (SARS) to human life, some of the most urgent challenges are to develop fast and accurate analytical methods for early diagnosis of this disease as well as to create a safe anti-viral vaccine for prevention. To these ends, we investigated the antigenicity of the spike protein (S protein), a major structural protein in the SARS-coronavirus (SARS-CoV). Based upon the theoretical analysis for hydrophobicity of the S protein, 18 peptides were synthesized. Using Enzyme-Linked Immunosorbent Assay (ELISA), these peptides were screened in the sera from SARS patients. According to these results, two fragments of the S gene were amplified by PCR and cloned into pET-32a. Both S fragments were expressed in the BL-21 strain and further purified with an affinity chromatography. These recombinant S fragments were confirmed to have positive cross-reactions with SARS sera, either by Western blot or by ELISA. Our results demonstrated that the potential epitope regions were located at Codons 469-882 in the S protein, and one epitope site was located at Codons 599-620. Identification of antigenic regions in the SARS-CoV S protein may be important for the functional studies of this virus or the development of clinical diagnosis.
Antigens, Viral ; immunology ; Chromatography, High Pressure Liquid ; Cloning, Molecular ; Electrophoresis, Polyacrylamide Gel ; Enzyme-Linked Immunosorbent Assay ; Genetic Vectors ; Humans ; Mass Spectrometry ; Membrane Glycoproteins ; genetics ; immunology ; metabolism ; Molecular Weight ; Peptide Fragments ; chemistry ; Recombinant Proteins ; genetics ; immunology ; SARS Virus ; genetics ; immunology ; metabolism ; Spike Glycoprotein, Coronavirus ; Viral Envelope Proteins ; genetics ; immunology ; metabolism

BACKGROUND:The use of normal hyaline cartilage to repair large areas of full-thickness knee cartilage defect has been a hot topic recently; however, a follow-up study with a relative large number of patients is required. OBJECTIVE:To make a preliminary study concerning the methods and therapeutic effects of tissue-engineered cartilage (TEC) implantation for treating large-area full-thickness knee cartilage defects. METHODS:Twenty-one patients (23 knees) diagnosed with cartilage defect of the knee joint (Outbridge III-IV) were enrolled. The area of the cartilage defect was 3.5-11.2 cm2. All of the patients were given TEC treatment. Postoperative functional exercise of the knee joint was carried out in these patients as planned. We regularly reviewed the knee MRI and calculated visual analog scale score, International Knee Documentation Committee (IKDC) score, and Lysholm score. RESULTS AND CONCLUSION:All the patients were followed up for 3 to 12 months. Postoperatively knee pain relieved obviously, and the visual analog scale score was significantly declined compared with the preoperation (P<0.05). All the patients manifested painless 1 year after surgery. The 1-year postoperative MRI showed that the injured cartilage grew well. The thickness and MRI signal of the graft was the same as the normal cartilage, and the bone healed completely. The IKDC and Lysholm scores were significantly improved at 3, 6, 12 months after the surgery, and the difference was statistically significant before and after the surgery (P<0.05). Overall, TEC is an improved technique of chondrocyte implantation, which is an effective and safe method for cartilage defect repair.

Objective:To design a new V-shaped forearm flap and to investigate the possibility of direct donor site closure and its value in the reconstruction of soft tissue defect after resection of buccal carcinoma.Methods:The new V-shaped forearm flap technique was applied in 10 patients with buccal carcinoma from October, 2018 to September, 2019. There were 6 males and 4 females aged from 35 to 63 years (48.3 years in average). Flap size ranged from 3.0 cm×5.0 cm to 4.0 cm×6.0 cm. Wound healing and the appearance forearm were recorded and evaluated three months after the surgery. Radial deviation angle, wrist flexion, ulnar deviation and dorsal extension were measured and calculated 3 months after the surgery. The wrist function was evaluated according to the Gartland-Werley scale. The recovery of wrist function was evaluated by comparing with the preoperative data.Results:Forearm donor sites were successfully closed without skin grafting in all 10 patients. Skin ischemia caused by excessive tension was observed at the incision edge in 3 patients, therefore leading to skin exfoliation and pigment loss without affecting wound healing. All patients were presented a cosmetic outcome during the follow-up period. No scar hyperplasia was observed. No significant difference was observed in perioperative wrist flexion angle, dorsal extension angle, radial deviation angle, ulnar deviation angle ( P>0.05)[data before surgery were (57.8±1.3) °, (58.4±0.7) °, (18.2±0.5) °, (28.5±1.1) ° respectively, and data 3 months after surgery were (53.2±2.1) °, (55.3±1.8) °, (16.4±0.4) °, (25.4±1.4) ° respectively]; Excellent and good rate of Gartland-Werley wrist score before and after surgery were both 100%. Conclusion:The new V-shaped free forearm flap can directly close small to medium forearm flap donor site. This method could avoid the trauma and complications of traditional free skin graft. The postoperative appearance on donor site is satisfactory and will not have adverse effects on wrist function. The new V-shaped free forearm flap is a novel method for repair of the defect of soft tissue defect after buccal cancer and it is worth to be applied in clinical practice.