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Fei Gao

Publications and source records attributed to Fei Gao.

At least 37 records · Page 2Linked to original sources
PubMed2006

Stereotactic radiosurgery plus intracavitary irradiation in the salvage of nasopharyngeal carcinoma.

BACKGROUND: We sought to assess the efficacy and complications of linear accelerator-based stereotactic radiosurgery (SRS) plus intracavitary irradiation (ICI) as salvage treatment for local persistent and recurrent nasopharyngeal carcinoma (NPC) after primary external beam radiotherapy (EBRT). METHODS: Between July 1995 and June 2003, 36 patients (25 men and 11 women; median age, 48 years; range, 22-66 years) with local recurrent NPC confined to the nasopharynx (rT1) or limited extension to the parapharynx and nasal cavity (rT2) were treated with SRS plus ICI. Nineteen patients had rT1 and 17 had rT2 disease. Five patients (13.8%) had persistent disease, and 31 patients (86.1%) had recurrent disease using the definition of >4 months after the primary treatment as recurrent relapse. The median target volume was 36.3 cm(3) (range, 10.3-56.2 cm(3)) for the SRS treatment. All patients received 18 Gy to the 90% isodose line followed by two separate ICI 6 Gy each to 0.5 cm from the surface of the endotracheal balloon. Patients were assessed with serial nasoendoscopy and repeat scans (CT or MRI) at 3 months, and suspicious lesions were rebiopsied. RESULTS: The median follow-up for surviving patients was 4.24 years (range, 0.73-8.81 years). Twenty-two of 36 (61%) patients were alive at the time of reporting. Twenty patients were free of disease, and two patients were alive with disease. Fourteen of 36 (39%) patients had died (five of distant metastases, six of local recurrences, two of both local disease and distant metastases, and one of unrelated cause). Patients with rT1 disease (median survival not reached) fared better that patients with rT2 disease (median survival, 4.6 years). The actuarial 5-year disease-free survival and overall survival (OS) were 57% (rT1 78%, rT2 39%) and 62% (rT1 80%, rT2 48%), respectively. The actuarial 5-year local control was 65% (rT1 82%, rT2 49%). The treatment was well tolerated with no significant acute complications. Sixteen patients (44%) had late complications, including palatal fibrosis in six patients (17%), trismus in seven patients (20%), cranial nerve palsies in seven patients (20%), temporal lobe necrosis in two patients (8%), and osteoradionecrosis of the skull base in six patients (17%). The complication-free survival rates at 2 and 5 years were 70% (95% confidence interval [CI], 56% to 87%) and 31% (95% CI, 17% to 56%), respectively. No patient died as a direct result of the late complication. CONCLUSION: Although our series is small, the combination of SRS and ICI seems to be an effective salvage treatment for early-stage recurrent NPC. The OS of 62% at 5 years is very encouraging and favorable compared with reported reirradiation or surgical series. The late complications are considerable but expected because of the high doses of radiation previously delivered. The ideal dose fractionation for SRS and ICI is unknown and remains to be defined.

Adult↗
PubMed2006

Fragmentation study of hexanitrostilbene by ion trap multiple mass spectrometry and analysis by liquid chromatography/mass spectrometry.

The fragmentation pathways of three explosive compounds with similar structures, hexanitrostilbene (HNS), cyclotrimethylene trinitramine (RDX), and 2,4,6-trinitrotoluene (TNT), have been investigated by multiple mass spectrometry (MSn, n = 1, 2, 3) with electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) sources. The electron capture mechanism for these compounds in negative ion APCI and ESI mode differs from the usual negative ion mechanism, deprotonation or addition of other species. This was shown for HNS and TNT, which both gave a [M]- anion but not a [M-H]- ion in APCI, and the [M]- anion of HNS was observed in ESI. The quantitative analysis of HNS was performed by liquid chromatography (LC)/ESI-MS, and the results obtained by the internal standard (ISTD) method were compared with those from the external standard (ESTD) method, demonstrating that both quantitation approaches are useful, with good sensitivity, reproducibility and linearity, and ESTD is preferable in routine applications.

Chromatography, High Pressure Liquid↗
PubMed2006

Defining pelvic factors in sphincter-preservation of low rectal cancer with a three-dimensional digital model of pelvis.

PURPOSE: Surgeons often can contribute failure of sphincter-preserving procedure to a limitation of pelvis anatomy; however, they cannot determine definitely which anatomic diameter or spatial factor actually affected the success of the procedure. METHODS: Colorectal surgeons, radiologists, and research fellows collaborated closely to establish a three-dimensional digital model of the pelvis with spiral computerized tomography scanning data of patients with rectal cancer. Retrospective analysis on data of 97 patients with low rectal cancer was performed with this model to identify geometric factors that might affect a successful sphincter preservation procedure for low rectal cancer. RESULTS: A digital pelvic model was established. Multivariate analysis demonstrated that distance from the anal verge, body mass index, and pelvic factors affected the success of sphincter preservation. Sphincter preservation was more likely to succeed when the distance from anal verge was > or =5 cm and body mass index was <25 kg/m(2). Shorter diameter from the upper pubis to the sacrococcyx, distance of sacrococcyx, and excessive curvature of the sacrum predicted failure of sphincter preservation in certain cases. CONCLUSIONS: Pelvic diameters could affect the success of sphincter preservation for low rectal cancer patients besides the distance from anal verge and body mass index.

Anal Canal↗
PubMed2006

Temporal and spatial expression of MMP-2, -9, -14 and their inhibitors TIMP-1, -2, -3 in the corpus luteum of the cycling rhesus monkey.

The corpus luteum (CL) is a transient endocrine organ that secretes progesterone to support early pregnancy. If implantation is unsuccessful, luteolysis is initiated. Extensive tissue remodeling occurs during CL formation and luteolysis. In this study, we have studied the possible involvement of MMP-2, -9, -14, and their inhibitors, TIMP-1, -2, -3 in the CL of cycling rhesus monkey at various stages by in situ hybridization, immunohistochemistry and microscopic assessment. The results showed that the MMP-2 mRNA and protein were mainly expressed in the endothelial cells at the early and middle stages of the CL development, while their expressions were observed in the luteal cells at the late stage during luteal regression. MMP-9 protein was detected in the CL at the early and middle stages, and obviously increased at the late stage. The expressions of MMP-14 and TIMP-1 mRNA were high at the early and late stages, and low at the middle stage. TIMP-2 mRNA was high throughout all the stages, the highest level could be observed at the late stage. The TIMP-3 production was detected throughout all the stages, but obviously declined during CL regression. MMP-9, -14 and TIMP-1, -2, -3 were mainly localized in the cytoplasm of the steroidogenic cells. The results suggest that the MMP/TIMP system is involved in regulation of CL development in the primate, and the coordinated expression of MMP-2, -14 and TIMP-1, -3 may have a potential role in the CL formation and the functional maintaining, while the interaction of MMP-2, -9, -14 and TIMP-1, -2, -3 might also play a role in CL regression at the late stage of CL development in the primate.

Animals↗
PubMed2006

Primary evidence for involvement of IP3 in heat-shock signal transduction in Arabidopsis.

The role of inositol 1,4,5-trisphosphate (IP(3)) in transducing heat-shock (HS) signals was examined in Arabidopsis. The whole-plant IP(3) level increased within 1 min of HS at 37 degrees C. After 3 min of HS, the IP(3) level reached a maximum 2.5 fold increase. Using the transgenic Arabidopsis plants that have AtHsp18.2 promoter-beta-glucuronidase (GUS) fusion gene, it was found that the level of GUS activity was up-regulated by the addition of caged IP(3) at both non-HS and HS temperatures and was down-regulated by the phospholipase C (PLC) inhibitors {1-[6-((17beta-3-Methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl]-2,5-pyrrolidinedione}(U-73122). The intracellular-free calcium ion concentration ([Ca(2+)](i)) increased during HS at 37 degrees C in suspension-cultured Arabidopsis cells expressing apoaequorin. Treatment with U-73122 prevented the increase of [Ca(2+)](i) to some extent. Above results provided primary evidence for the possible involvement of IP(3) in HS signal transduction in higher plants.

Aequorin↗
PubMed2006

Electroacupuncture for refractory acute emesis caused by chemotherapy.

PURPOSE: To evaluate the efficacy of electroacupuncture in preventing anthracycline-based chemotherapy-related nausea and emesis refractory to combination 5HT(3)-antagonist and dexamethasone. PATIENTS AND METHODS: Cancer patients with refractory emesis after their first cycle of doxorubicin-based chemotherapy were accrued into this study. Electroacupuncture was given during the second cycle of chemotherapy. Each patient was evaluated for the number of emetic episodes and grade of nausea within the first 24 hours after chemotherapy and electroacupuncture. RESULTS: Forty-seven of a total of 317 patients screened were eligible for this study. Of these, 27 patients agreed to participate. Twenty-six (26; 96.3%) of them had significant reduction in both nausea grade and episodes of vomiting after electroacupuncture. There was complete response with no emetic episodes in 37%. Subjectively, 25 (92.6%) of the total 27 patients believed that acupuncture was an acceptable procedure and was helpful in reducing emesis. Electroacupuncture was well-tolerated with a median pain score of 3 of 10. CONCLUSION: Electroacupuncture is well-tolerated and effective as an adjunct in reducing chemotherapy-related nausea and emesis.

Adult↗
PubMed2006

[Research on the expression of cancer associated gene in the intracranial tumors].

OBJECTIVE: To investigate the function significance and application value of cancer associated gene (CAGE) in the pathogenesis of intracranial tumors. METHODS: Semi-quantitative RT-PCR was performed to detect the expression of CAGE gene in 17 normal tissues, 35 meningioma cases and 63 glioma cases. RESULTS: The CAGE gene was expressing in none of the normal tissues except testis, but in 4 meningioma (11.3%) and 57 glioma cases(90.5%). The expression of CAGE gene showed significant difference between the meningioma and glioma (P<0.001). The amount of CAGE mRNA was 0.5 +/- 0.11, 0.86 +/- 0.23, 1.85 +/- 0.37 or 2.7 +/- 0.46 times of the internal control one in glioma grade I, II, or IV respectively. The expression of CAGE gene increased with the pathological grade(r=0.82). CONCLUSION: The CAGE plays important role in the pathogenesis of glioma, and may act as the tumor specific antigen for glioma.

Adult↗
PubMed2006

[Clinicopathological features of solid pseudopapillary tumor of the pancreas].

OBJECTIVE: To elucidate the clinicopathological features of solid pseudopapillary tumor (SPT) of the pancreas. METHODS: Eight patients with SPT of the pancreas admitted from August 1996 to March 2005 were retrospectively analyzed. RESULTS: All the 8 patients were female with an average age of 25.3 (13-41) years. The primary clinical manifestations included abdominal mass (n = 3), vague abdominal pain (n = 3), and duodenal obstruction (n = 1). SPT was occasionally found in one patient during physical examination. Six tumors located at the head and the other two in the body and tail of the pancreas. Pancreaticoduodenectomies were performed in 4 patients, tumor enucleations in 2, distal pancreatectomies in 1, and palliative internal drainage with a cystoenterotomy in the other one with an unresectable huge cystic lesion. All patients were alive on an average follow-up of 37.8 (8-103) months. CONCLUSION: SPT occurs mainly in adolescent and young females, and satisfactory outcome may be achieved with active and appropriate surgeries.

Adolescent↗
PubMed2006

[Study on primary hepatocellular carcinoma associated with hypersplenism treated by partial splenic embolization combined with hepatic arterial chemoembolization].

BACKGROUND & OBJECTIVE: 70-90% of patients of primary hepatocellular carcinoma (PHC) are associated with liver cirrhosis, portal hypertension and hypersplenism. The treatment of PHC is usually hampered by low or slow recovery of blood cell counts. This study was to investigate the effect of partial splenic embolization (PSE) combined with transcatheter hepatic arterial chemoembolization (TACE) for the treatment of PHC with portal hypertension and hypersplenism. METHODS: Efficacy of 26 patients with PSE combined with TACE and 26 patients with single TACE was observed. RESULTS: Satisfactory effects were achieved in PSE combined with TACE group in terms of correction of blood cell counts compared with cases treated with TACE alone. CONCLUSION: PSE associated with TACE is safe and effective for the treatment of patients with PHC associated with liver cirrhosis, portal hypertension and hypersplenism.

Adult↗
PubMed2006

[The effects of matrine on cell proliferation and telomerase activity in retinoblastoma cells in vitro].

OBJECTIVE: To evaluate the effects of matrine on cell proliferation and telomerase activity in retinoblastoma cells in vitro. METHODS: HXO-Rb44 cells were treated with 0.1 to 3.2 mmol/L matrine for 24 h, then cell viability was measured by MTT assay. Apoptosis rates were evaluated by flow cytometry and TUNEL assay after the cells were treated for various durations. The telomerase activity were measured by telomeric repeat amplification protocol. RESULTS: MA inhibited the growth of HXO-Rb44 cells. Ma induced the apoptosis and down-regulated the telomerase activity of HXO-Rb44 cells, which were time dependent. There was a positive correlation between the telomerase activity and the apoptosis (r = -0.961, P < 0.01). CONCLUSIONS: Ma can induce the apoptosis and down-regulate the telomerase activity of retinoblastoma cells, which may be one of important mechanisms to inhibit the cell proliferation. It suggests that Ma may be a potent drug for the treatment of retinoblastoma.

Alkaloids↗
PubMed2005

Variation in the seasonal diagnosis of acute lymphoblastic leukemia: evidence from Singapore, the United States, and Sweden.

This study investigated, by summing data over successive years, the evidence for the seasonal diagnosis of acute lymphoblastic leukemia. To do so, the authors estimated the dates of peak diagnosis over a range of geographic locations including Singapore (1968-1999), Hawaii and mainland United States (1973-1999), and western Sweden (1977-1994) at latitudes of 1.16 degrees N to 58.24 degrees N. In contrast to other studies, the authors used case-by-case information on dates, gender, and age rather than grouped data for analysis. The seasonal pattern was estimated by fitting a von Mises distribution to the data from each location. No seasonal pattern was found in Singapore, which is close to the equator and does not have marked climatic changes. Likewise, seasonality was not demonstrated in Hawaii or mainland United States despite a 26.18 degrees range of latitudes. In contrast, a significant peak (early January) was observed for western Sweden that appeared strongest for males (December 22, 95% confidence interval: November 16, January 16) and those less than age 20 years (January 14, 95% confidence interval: December 8, March 27). Thus, despite a wide geographic range of localities, there is little evidence of any seasonality in the diagnosis of acute lymphoblastic leukemia in most populations studied and no strong evidence of any influence of climate (as expressed by latitude).

Adolescent↗
PubMed2005

[Expression and antigenicity analysis of p46000 antigen from newborn larvae of Trichinella spiralis].

OBJECTIVE: To express and analyze p46000 antigen from newborn larvae of Trichinella spiralis. METHODS: p46000 antigen gene was subcloned to the pET28a expression system by PCR. The recombinant transformant was induced by IPTG and the antigenicity was analyzed with ELISA and Western blotting. RESULTS: The molecular weight of the expressed protein was about Mr 48000. ELISA and Western blotting showed that this recombinant protein could be recognized by T. spiralis infected swine serum and rabbit anti-recombinant protein serum, and the rabbit anti-recombinant protein serum could recognize a Mr 46000 protein from newborn larvae of T. spiralis. CONCLUSION: p46000 recombinant antigen from newborn larvae of T. spiralis was expressed which shows a specific antigenicity.

Animals↗
PubMed2005

Involvement of molecules related to angiogenesis, proteolysis and apoptosis in implantation in rhesus monkey and mouse.

We have established the well-defined cycling, pseudo-pregnant and pregnant rhesus monkey models, and used these to analyze expression of the common molecules specifically related to angiogenesis, apoptosis or proteolysis, such as vascular endothelial growth factor (VEGF) and its receptors KDR, flt-1, flt-4 and flk-1, basic fibroblast growth factor (bFGF) and its receptors Flg, transforming growth factor-alpha and beta1 (TGF-a/beta1), and TGF-beta1 receptor type I (TbetaR-I) and type II (TbetaR-II), as well as steroidogenic acute regulatory protein (StAR), tissue type plasminogen activator/urokinase plasminogen activator/plasminogen activator inhibitor type 1 (tPA/uPA/PAI-1) and matrix matalloproteinase type 1, -3/tissue inhibitor matalloproteinase type 1, -2, -3 (MMP-1, -3/TIMP-1, -2, -3), Fas/FasL, BcL-2/Bax, in the corpus luteum (CL), in the functional layer of the endometrium and in the materno-fetal boundary of the implantation site. We have demonstrated that: expression of these molecules in the monkey CL, endometrium and materno-fetal boundary of the implantation site is correlated well with CL functional and vascular development and with the processes involved in the establishment of the implantation window as well as with the early stages of placentation. A coordinated increase in tPA and its inhibitor PAI-1 expression in the monkey and rat CL may be instrumental in initiating luteal regression in both species, and correlated well with the timing of the closure of the implantation window, whereas high uPA activity in the CL is important for the early formation of the CL and for maintaining its function which is closely correlated to the period of establishment of the implantation window. Apoptosis, proteolysis and angiogenesis occur in the CL and in the endometrium during the time of establishment of the implantation window, as well as in the materno-fetal boundary of the implantation site at the early stages of placentation. It seems that these processes occur in these tissues in a coordinated and time- and cell-dependent manner, and are reliant on each other. Based on these observations, we have designed experiments to test the actions of some related available compounds on mouse implantation, used alone or in combination. The preliminary data showed that the compounds which could effectively affect apoptosis, angiogenesis or proteolysis in the implantation site were capable of effectively inhibiting implantation by acting on the endometrium and/or on the CL. Furthermore, the combined use of these compounds produced an obvious additive effect on inhibiting implantation. This finding suggested this may be a good approach for developing an anti-implantation agent.

Animals↗
PubMed2005

Intranasal CpG-oligodeoxynucleotide is a potent adjuvant of vaccine against Helicobacter pylori, and T helper 1 type response and interferon-gamma correlate with the protection.

BACKGROUND: Although a series of vaccines against Helicobacter pylori have emerged in the past 10 years, the mechanism involved in their protective effect is yet to be elucidated, and more effective vaccine adjuvants remain to be developed. In this study, CpG-oligodeoxynucleotide (CpG-ODN) was investigated as a new candidate for a H. pylori vaccine adjuvant. Furthermore, the role of T helper 1 (Th1) type response and interferon (IFN)-gamma in the protective immunity was explored. METHODS: C57BL/6 mice and IFN-gamma knockout mice were intranasally or orally immunized with H. pylori whole cell sonicate (WCS)/CpG-ODN and challenged with different doses [5 x 10(8) and 5 x 10(6) colony-forming units (CFU)] of H. pylori. The protective effect was assessed as the percentage of noninfected mice. The responsive antibodies and cytokines were analyzed using an enzyme-linked immunosorbent assay (ELISA) and flow cytometry. RESULTS: The prevention rates against H. pylori infection in mice intranasally immunized with WCS plus CpG-ODN were dramatically higher than those in sham-immunized mice (70% vs. 0%, challenged with 5 x 10(8) CFU H. pylori; 90% vs. 20%, challenged with 5 x 10(6) CFU H. pylori). Significantly higher levels of immunoglobulin G2a (IgG2a) and IFN-gamma were detected in the mice immunized with WCS/CpG than in sham-immunized controls. However, vaccination failed to effectively protect IFN-gamma knockout mice challenged with H. pylori. CONCLUSIONS: CpG-ODN given intranasally is a potent adjuvant for development of a H. pylori vaccine. Th1-type response and IFN-gamma are involved in the protection.

Adjuvants, Immunologic↗
PubMed2005

[Clinical and pathological features of 112 cases with ocular adnexal lymphoproliferative lesions].

OBJECTIVE: To investigate the histopathological classification and clinical features of ocular adnexal lymphoproliferative lesions. METHODS: The clinical, histomorphological and immuno-histochemical features of 112 cases of ocular adnexal lymphoproliferative lesions (116 paraffin specimens) were studied retrospectively. The lesions were classified according to the World Health Organization classification of tumors of haematopoietic and lymphoid tissues (2001). RESULTS: This group of patients' ages averaged at 49. The mean duration between the onset of the symptoms and the time of presentation was 22 months. Sixteen patients (14.3%) had bilateral lesions. Proptosis or local orbital mass was presented in 69 cases (61.6%). Reactive lymphoid hyperplasia was diagnosed in 11 cases (9.8%) and atypical lymphoid hyperplasia in 10 cases (8.9%). The rest 91 cases (81.3%) were diagnosed as lymphoma, among which 74 cases (81.3%) were extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT-EMZL). CONCLUSIONS: MALT-EMZL is the most frequent type of ocular lymphoproliferative lesions in ocular adnexa. The ocular adnexal lymphoproliferative lesions show an indolent course clinically, tending to affect the old. Bilateral case is not uncommon.

Adolescent↗
PubMed2005

[Application of Raman spectra to the research of jades excavated from Xue Jiagang site].

Non-destructive analysis is always the aim in jades' research. The present article applied the Raman spectroscopy to the research on jades excavated from the Xue Jiagang site and achieved good result in the main mineral, inclusion and phenocryst. The study shows that as a non-destructive technique Raman spectroscopy can be applied to ancient jades conveniently and practically, and it can detect not only the surface information of ancient jades, but also the interior information. The technique is important to the verification and provenance of ancient jades.

China↗
PubMed2004

Does the 12-item General Health Questionnaire contain multiple factors and do we need them?

BACKGROUND: The 12-item General Health Questionnaire (GHQ-12) is widely used as a unidimensional instrument, but factor analyses tended to suggest that it contains two or three factors. Not much is known about the usefulness of the GHQ-12 factors, if they exist, in revealing between-patient differences in clinical states and health-related quality of life. METHODS: We addressed this issue in a cross-sectional survey of out-patients with psychological disorders in Singapore. The participants (n = 120) completed the GHQ-12, the Beck Anxiety Inventory, and the Short-Form 36 Health Survey. Confirmatory factor analysis was used to compare six previously proposed factor structures for the GHQ-12. Factor scores of the best-fitting model, as well as the overall GHQ-12 score, were assessed in relation to clinical and health-related quality of life variables. RESULTS: The 3-factor model proposed by Graetz fitted the data better than a unidimensional model, two 2-factor models, and two other 3-factor models. However, the three factors were strongly correlated. Their values varied in a similar fashion in relation to clinical and health-related quality of life variables. CONCLUSIONS: The 12-item General Health Questionnaire contains three factors, namely Anxiety and Depression, Social Dysfunction, and Loss of Confidence. Nevertheless, using them separately does not offer many practical advantages in differentiating clinical groups or identifying association with clinical or health-related quality of life variables.

Adult↗