Biomedical subjects

G Tu

Publications and source records attributed to G Tu.

At least 19 recordsLinked to original sources

PubMed2001

The value of a hospitalist service: efficient care for the aging population?

BACKGROUND: We studied patients of a hospitalist teaching service and patients receiving routine private care (control subjects). We sought to evaluate whether inpatients cared for by an academic hospitalist service had lower lengths of stay and resource utilization rates. METHODS: Using monthly hospital census data, 477 hospitalist cases and 1,160 control cases were selected by explicit criteria from the Medicaid population of a large, university-affiliated, community medical center between July 1, 1996, and June 30, 1997. Outcomes in hospitalist faculty patients were compared to those of control patients under the care of private providers. RESULTS: Median length of stay was 4 days for control subjects and 3 days for the hospitalist service (p < 0.0001). Median total cost per case was $4,853 for control subjects and $4,002 for hospitalist patients (p < 0.0001). Only patients > or = 65 years old showed statistically significant reductions in both length of stay (p < 0.0001) and total cost (p = 0.002). Subspecialty consultation rates were 37.6% for control subjects and 16.6% for hospitalist cases (p < 0.0001). We noted increasing consultations for patients > or = 65 years old, especially in the control group (p = 0.001). No significant differences in mortality, 30-day readmissions, or interfacility transfers were observed. CONCLUSIONS: Patients cared for by an academic hospitalist service that includes actively participating medical residents appear to have lower lengths of stay, total costs, and consultation rates than patients receiving routine private care. The reductions are largely observed among patients > or = 65 years old.

Adolescent↗

PubMed2000

Non-replicating Epstein-Barr virus-based plasmids extend gene expression and can improve gene therapy in vivo.

To date, no gene transfer vector has produced prolonged gene expression following a single intravenous injection and then efficiently re-expressed the delivered gene following repeated systemic injection into immunocompetent hosts. To overcome these limitations, a gene therapy regimen using non-replicating Epstein-Barr virus (EBV)-based expression plasmids was developed. One plasmid contains the FR (EBV family of repeats) sequence and the expressed gene. The other encodes Epstein-Barr nuclear antigen 1 (EBNA-1), but lacks FR. Although unable to replicate in mice, intravenous co-injection of EBV-based plasmids in cationic liposome-DNA complexes (CLDCs) substantially prolonged luciferase gene expression. The use of a two-vector system limited host exposure to the EBNA-1 gene product. Furthermore, this EBV-based vector system could be intravenously re-injected multiple times into immunocompetent mice without loss of transfection efficiency. Use of this vector system significantly improved the therapeutic efficacy of the biologically important human granulocyte colony-stimulating factor gene. Delivery of the human granulocyte colony-stimulating factor gene in EBV-based plasmids increased circulating white blood counts for at least 2 months following a single CLDC-based intravenous co-injection. Conversely, white blood counts were never elevated following injection of CLDCs lacking EBV-derived elements. Thus, this EBV-based plasmid vector system both markedly prolongs gene expression at therapeutic levels and efficiently and repeatedly re-transfects immunocompetent hosts. These properties of EBV-based plasmid vectors appear to be due, at least in part, to the documented abilities of the EBNA-1 protein both to retain FR-containing DNA intracellularly and within the nucleus and to block anti-EBNA-1 cytotoxic T cell responses.

Animals↗

PubMed2000

Two diastereomeric saponins with cytotoxic activity from Albizia julibrissin.

Two diastereomeric saponins, julibrosides J1 (1) and J9 (2), both of which show cytotoxic activity, were obtained from the stem bark of Albizia julibrissin Durazz. On the basis of chemical and spectral evidence [L.B. Ma et al., Carbohydr. Res., 281 (1996) 35-46], the structure of 1 was revised as 3-O-[beta-D-xylopyranosyl-(1-->2)-alpha-L-arabinopyranosyl-(1-->6) -beta-D-glucopyranosyl]-21-O-[(6S)-2-trans-2-hydroxymethyl-6-methyl-6-O- [4-O-((6R)-2-trans-2,6-dimethyl-6-O-(beta-D-quinovopyranosyl)-2,7- octadienoyl)-beta-D-quinovopyranosyl]-2,7-octadienoyl] acacic acid-28-O-beta-D-glucopyranosyl-(1-->3)-[alpha-L-arabinofuranosyl-(1-->4 )]-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl ester. The diastereoisomer 2 of 1 was identified as 3-O-[beta-D-xylopyranosyl-(1-->2)-alpha-L-arabinopyranosyl-(1-->6) -beta-D-glucopyranosyl]-21-O-[(6S)-2-trans-2-hydroxymethyl-6-methyl-6-O- [4-O-((6S)-2-trans-2,6-dimethyl-6-O-(beta-D-quinovopyranosyl)-2,7- octadienoyl)-beta-D-quinovopyranosyl]-2,7-octadienoyl] acacic acid-28-O-beta-D-glucopyranosyl-(1-->3)-[alpha-L-arabinofuranosyl-(1-->4 )]-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl ester. Saponin 2 is a new saponin named julibroside J9. Both julibrosides J1 and J9 show good inhibitory action against the KB cancer cell line in vitro.

Antineoplastic Agents↗

PubMed2000

[The treatment of tongue squamous cell with N0].

OBJECTIVE: To evaluate the validity of selective surgery for the N(0) neck in squamous cell carcinoma of the mobile tongue. METHODS: 116 patients with N(0) neck of the mobile tongue cancer who underwent comprehensive RND and 5 patients who had a selective RND were reviewed retrospectively. RESULTS: According to the suggestion of division of neck level, 7 patients had metastasis at level I; 21, level II; 10, level III, 1 case for level IV or V each. There were 5 cases with level III involvement as a first echelon of metastasis which was peculiar for the neck metastasis of mobile tongue. CONCLUSIONS: For N(0) neck of the mobile tongue cancer, a neck dissection of level I-III or level I-IV is more than enough.

Aged↗

PubMed2000

[Laryngeal function-sparing surgery for pyriform sinus cancer].

OBJECTIVE: To evaluate the oncologic effect of laryngeal function-sparing surgery for the patients with pyriform sinus carcinoma. METHODS: A retrospective analysis was performed. Forty-four patients with pyriform sinus cancer who underwent operations were included. There were 10 patients in T1, 14 in T2, 18 in T3 and 2 in T4 categories. 42 patients received preoperative radiation and 2 cases, post-operative radiation. Surgery for the local lesions: 36 patients underwent pyriform sinusectomy and 8, partial laryngectomy and pyriform sinusectomy. RESULTS: Five year survival rate is 50% for the whole series, 80% for stage I, 71.4% for stage II, 52.9% for stage III, 26.7% for stage IV and 45% for all T3 + T4 patients. Local control rate is 81.8% for all patients and 75% for T3, T4 patients. CONCLUSION: For selected pyriform sinus cancer patient a conservative laryngeal surgery is warranted with the combination of preoperative radiative therapy.

Adult↗

PubMed2000

[The status of protein P16 and P53 in the surgical margins of laryngeal carcinoma and the association with local recurrence].

OBJECTIVE: To assess the status of P53 and P16 of surgical margins in laryngeal carcinoma and the association with the local recurrence following surgical treatment METHODS: The status of P53 and P16 of surgical margins in laryngeal carcinoma was studied using immunohistochemistry (IHC) staining method in 100 cases of laryngeal carcinoma. Fifty-two of them had recurrent tumors while 48 cases were free of local recurrence after 5-year follow up. The original tumor sites and T stages, which bear important influence over the risk of local recurrence, were strictly matched between the two groups, and the ages and preoperative doses of radiation were also considered. RESULTS: The percentage of local recurrence was 85% in these patients who showed positive staining for P53 and simultaneous negative staining for P16 in both the cancer tissues and the surgical margins. No association was found between the expression of P53 and P16 and the clinical types or T stages. CONCLUSION: The status of P53 and P16 in combination demonstrated by IHC technique in surgical margins of laryngeal carcinoma may predict the possibility of local recurrence.

Adult↗

PubMed2000

[Lateral neck dissection of hypopharyngeal cancer with clinically regional metastasis].

OBJECTIVE: To assess whether lateral neck dissection can control the hypopharyngeal cancer with clinically regional metastasis. METHODS: A retrospective review of medical chart from 1975 to 1992 was performed. Ninety-three hypopharyngeal squamous cell carcinoma patients who had performed RND were included. The distribution of metastatic neck lymph node was analyzed. RESULTS: Submandibular triangle lymph node metastasis was occult in only 3 patients. Histological lymph node metastasis to the posterior triangle was found in 5.9% of patients with N0, 7.0% with N1, 37.5% with N2a and 36% with N2b-N3. Histological neck lymph node metastasis to the posterior triangle was found in 4.0% of patients without inferior jugular lymph node metastasis and 34.1% of patients with inferior jugular lymph node metastasis. CONCLUSIONS: Lateral neck dissection was recommended to treat hypopharyngeal cancers of N0 and N1. N2 and N3 should be treated with neck dissection including II-V group lymph nodes. After lateral neck dissection, frozen section of the inferior jugular lymph node should be performed. If the result of the frozen section is positive, V group dissection should be performed.

Adult↗

PubMed2000

[IR search through Internet].

In our laboratories, we have almost had the complete Sadtler IR database, about 133,000 spectra. Based on Sadtler IR Search Master software, off-line spectrum search through internet has been set up in this work. Customers e-mail their unknown spectra as attached files to ftir2000@sina.com or ftir@microchem.org.cn. After we download the unknown spectra and search them, we will send the search reports in Microsoft Word format back to the customers within 72 hours. Please visit our web site www.microchem.org.cn to know the policy about our IR search program.

Databases, Factual↗

PubMed1999

Gene expression along the cerebral-spinal axis after regional gene delivery.

We demonstrate here that intracerebroventricular or spinal cord (intrathecal) injection of either plasmid DNA alone or cationic liposome: DNA complexes (CLDCs) produces significant levels of expression of both reporter genes and biologically relevant genes in nonparenchymal cells lining both the brain and the spinal cord. Gene expression was identified both within the spinal cord and the brain after intracerebroventricular or intrathecal injection of either CLDCs or plasmid DNA alone. Intracerebroventricular or intrathecal injection of CLDCs containing the beta-galactosidase (beta-Gal) gene produced patchy, widely scattered areas of beta-Gal expression. The chloramphenicol acetyltransferase (CAT) reporter gene product reached peak levels between 24 hr and 1 week postinjection, and was still present at significant levels 3 weeks after a single intracerebroventricular or intrathecal injection. Intrathecal injection of the human granulocyte colony-stimulating factor (G-CSF) gene produced high levels of hG-CSF activity in both the spinal cord and the brain. Intracerebroventricular injection of CLDCs containing the murine nerve growth factor (NGF) gene increased mNGF levels in the hippocampus, a target region for cholinergic neurons in the medial septum, and increased cholinergic neurotransmitter synthetic enzyme choline acetyltransferase (ChAT) activity within the brain, a well-characterized effect of both purified and recombinant NGF protein. These findings indicate that intracerebroventricular or intrathecal injection of CLDCs can produce significant levels of expression of biologically and therapeutically relevant genes within the CNS. Efficient gene transfer into the CNS will facilitate the evaluation of gene function and regulation within the brain and spinal cord. We attempted to transfer and express genes within the brain and spinal cord by direct CNS injection of either DNA alone or CLDCs into the intraventricular and subarachnoid compartments. We show that intracerebroventricular or spinal cord (intrathecal) injection of either plasmid DNA alone or CLDCs produces significant levels of expression of both reporter genes and biologically relevant genes in nonparenchymal cells lining both the brain and the spinal cord. Intrathecal injection of the hG-CSF gene produced high levels of hG-CSF activity in both the spinal cord and the brain. Intracerebroventricular injection of CLDCs containing the murine NGF gene increased mNGF levels in the hippocampus, and increased cholinergic neurotransmitter synthetic enzyme ChAT activity within the brain. Locoregional diffusion of gene products expressed by transfected meningeal lining cells into brain and spinal cord parenchyma could potentially target secreted proteins within brain and spinal cord regions relevant to neuropathological states while limiting peripheral side effects.

Animals↗

PubMed1999

Systemic gene delivery expands the repertoire of effective antiangiogenic agents.

Cationic liposome-DNA complex (CLDC)-based intravenous gene delivery targets gene expression to vascular endothelial cells, macrophages and tumor cells. We used systemic gene delivery to identify anti-angiogenic gene products effective against metastatic spread in tumor-bearing mice. Specifically, CLDC-based intravenous delivery of the p53 and GM-CSF genes were each as effective as the potent antiangiogenic gene, angiostatin, in reducing both tumor metastasis and tumor angiogenesis. Combined delivery of these genes did not increase anti-tumor activity, further suggesting that each gene appeared to produce its antimetastatic activity through a common antiangiogenic pathway. CLDC-based intravenous delivery of the human wild type p53 gene transfected up to 80% of tumor cells metastatic to lung. Furthermore, it specifically induced the expression of the potent antiangiogenic gene, thrombospondin-1, indicating that p53 gene delivery in vivo may inhibit angiogenesis by inducing endogenous thrombospondin-1 expression. CLDC-based delivery also identified a novel anti-tumor activity for the metastasis suppressor gene CC3. Thus, CLDC-based intravenous gene delivery can produce systemic antiangiogenic gene therapy using a variety of different genes and may be used to assess potential synergy of combined anti-tumor gene delivery and to identify novel activities for existing anti-tumor genes.

Angiostatins↗

PubMed1999

Squamous cell carcinoma of temporal bone: reported on 33 patients.

BACKGROUND: This study assessed the treatment results of a series of 33 patients with squamous cell carcinoma (SCC) of the temporal bone and evaluated the efficacy of mastoidectomy combined with perioperative radiation therapy protocol. METHODS: Thirty-three patients with biopsy-proven SCC invaded to the temporal bone were reviewed retrospectively and staged into three subgroups according to the University of Pittsburgh TNM Staging System. There were 3 patients with Stage I and II disease(tumor confined to auditory canal), 17 patients with Stage III (tumor involving the middle ear or mastoid), and 13 patients with Stage IV(more extensive disease). Two patients were treated by surgery alone. Eleven patients received irradiation only, and the remaining 20 patients underwent combined surgery and perioperative radiotherapy. The surgical intervention included sleeve resection for patients with Stage I and II lesions and mastoidectomy for all patients with Stage III and IV lesions except 1 who had subtotal temporal bone resection. The radiation dose delivered was in the range of 3500 approximately 10 000 cGy, with an average dose of 6560 cGy. RESULTS: The five-year survival rate for the whole series was 51.7% by the life-table analysis. After being staged into three subgroups (ie, Stage I + II, Stage III, and Stage IV), the estimated five-year survival rates were 100%, 68. 8%, and 19.6%, respectively (p = 0.04). Radiation alone yielded a 28. 7% five-year survival, while combined surgery and irradiation gave a result of 59.6% (p = 0.80). For patients treated with planned combined therapy, the actuarial five-year survival rates were 72.7% (8/11) for Stage III disease and 12.5% (1/8) for Stage IV disease (p = 0.02). Twelve patients who died of disease did so of local recurrence (10 cases), cervical metastases (1 case), and liver metastases (1 case), with 70% of succumbing to their diseases within two years. Complications include osteonecrosis (n = 1), osteitis (n = 3), radiation dermatitis (n = 2), facial nerve palsy (n = 2), and delayed healing (n = 2). Data on clinical presentation and treatment modality were also analyzed. CONCLUSION: The results of mastoidectomy with removal of all gross tumor, combined with planned perioperative irradiation therapy, seems to be a useful approach for SCC of the temporal bone. This gives at least as good, and possibly better, five-year survival than temporal bone resection. The mastoidectomy procedure creates less operative morbidity and mortality. To facilitate the development of more effective means of treating advanced disease, an accepted staging system and cooperative group investigation is necessary.

Adult↗

PubMed1999

Saikosaponins from roots of Bupleurum scorzonerifolium.

Saikosaponin u and saikosaponin v, were isolated from the roots of Bupleurum scorzonerifolium and these saponins were identified as 3-O-[beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl- (1-->3)-beta-D-fucopyranosyl]-3 beta,16 alpha,23,28-tetrahydroxy-olean- 11,13(18)-dien-30-oic acid-30-O-[pentito(1-->1)-beta-D-glucopyranosyl-(6-->)] ester and 3-O-[beta-D-glucopyranosyl-(1-->3)-beta-D-fucopyranosyl]-3 beta,16 alpha,23,28-tetrahydroxy-olean-11,13(18)-dien-30-oic acid-30-O-[pentito(1-->1)-beta-D-glucopyranosyl(6-->)] ester, respectively.

Anti-Inflammatory Agents, Non-Steroidal↗

PubMed1999

Fetal gene transfer by transuterine injection of cationic liposome-DNA complexes.

In utero injection of cationic liposome-DNA complexes (CLDCs) containing chloramphenicol acetyltransferase, beta-galactosidase (beta-gal), or human granulocyte colony-stimulating factor (hG-CSF) expression plasmids produced high-level gene expression in fetal rats. Tissues adjacent to the injection site exhibited the highest levels of gene expression. Chloramphenicol acetyltransferase expression persisted for at least 14 days and was reexpressed following postnatal reinjection of CLDCs. Intraperitoneal administration of the hG-CSF gene produced high serum hG-CSF levels. X-gal staining demonstrated widespread beta-gal expression in multiple fetal tissues and cell types. No toxic or inflammatory responses were observed, nor was there evidence of fetal-maternal or maternal-fetal gene transfer, suggesting that CLDCs may provide a useful alternative to viral vectors for in utero gene transfer.

Animals↗

PubMed1999

Guidelines in pulmonary medicine: a 25-year profile.

OBJECTIVE: We attempted to identify clinical practice guideline and pathway articles in the area of pulmonary medicine published in peer-reviewed journals since 1974. DESIGN: Review. DATA SOURCES: MEDLINE, the Cochrane Database, Best Evidence, and Abstracts of Clinical Care Guidelines from January 1974 to December 1998. STUDY SELECTION: All articles contained relevant search terms for pulmonary topics and were included irrespective of setting (primary or specialty, inpatient or outpatient). Controlled and uncontrolled trials as well as observational studies and consensus opinion/statements were all identified. The articles were stratified by design as well as by pulmonary topic. DATA EXTRACTION: Limited data on study type, study focus, year of publication, and results of study were abstracted. RESULTS: Our criteria yielded 271 articles, including 115 consensus statements and expert opinion guidelines; 30 controlled studies, meta-analyses, or systematic reviews; and 126 uncontrolled trials and observational studies. Of these, 82 articles (30.3%) related to asthma, 46 articles (17.0%) related to COPD, and 36 articles (13.3%) related to pneumonia. In addition, we tracked the increasing publication of all guideline-related pulmonary articles; randomized, controlled trials (RCTs); systematic reviews; and consensus statements by year for the past 25 years. CONCLUSION: Pulmonary guidelines are increasingly published in peer-reviewed journals, but few are tested clinically in RCTs. There is continued reliance on consensus statements and expert opinion. Pulmonary guideline publications have continued to dramatically increase in number and in importance since 1974, both on the local level and internationally.

Asthma↗

PubMed1999

[Cervical management in the N0 squamous cell carcinoma of the tongue].

OBJECTIVE: To assess whether the elective neck dissection would be beneficial as a routine management in the N0 squamous cell carcinoma of the tongue. METHODS: Cox regression model was used for analysis of tongue cancer cases treated by our hospital in a period from 1958 to 1996. RESULTS: Size of primary tumor and preoperative radiation showed significant difference in relation to cervical lymph node recurrence or metastasis. Neck dissection in the series was not a factor to influence the rate of cervical recurrence or survival. 5-years survival was 73.5% versus 69.3% in patients who underwent elective neck dissection and those without neck dissection (difference not statistically significant). CONCLUSION: We suggest that elective neck dissection would be avoided in T1 or T2 patients who have no neck node metastases.

Adult↗

PubMed1999

[Selective neck dissection in the treatment of supraglottic carcinoma].

OBJECTIVE: To study the effectiveness of selective neck dissection (upper neck dissection, UND) in the treatment of N0 neck of supraglottic carcinoma. METHOD: The upper neck dissection was designed according to the lymphatic drainage of the supraglottic larynx for the management of N0 neck. The records of the supraglottic carcinoma of T1-4 N0-1 M0 cases (168 patients), who were treated in 1976-1990 at this hospital, were analysed retrospectively. RESULT: In this seires of 168 patients with no neck metastases pathologically a follow-up of five years after an upper neck dissection revealed a neck recurrence rate of 10.1% (17/168), which is comparable with those reported in the literature after selective neck dissection. Five year survival rate was 72.6% (122/168). CONCLUSION: Long-termed observation after UND for supraglottic carcinoma (T1-4 N0-1) resulted in satisfactory survival rates and regional control. It seems justifiable to do a selective neck dissection for N0 and selected N1 patients in order that more patients were exempted from enduring the morbidity following a comprehensive neck dissection.

Adult↗

PubMed1998

[Supraglottic horizontal laryngectomy for supraglottic carcinoma].

OBJECTIVE: To evaluate the therapeutic results of supraglottic horizontal laryngectomy (SHL) for T1 and selected T2, T3 and T4 supraglottic carcinoma. METHODS: One hundred and seven patients undergone SHL during the period of 1979 through 1991 were reviewed retrospectively. All patients were followed up for at least 5 years. RESULTS: The 5 year-survival rate of 6 cases in stage I, 24 cases in stage II, 53 cases in stage III, and 24 cases in stage IV was 100.0%, 83.3%, 71.7% and 41.7%, respectively. Of the 102 patients, 92.2% were decannulated, and 91.6% of all patients achieved satisfactory recovery of phonation. CONCLUSION: SHL is a reliable surgical approach for selected supraglottic carcinoma, even for some advanced lesions, provided the tumor has not extended below the ventricle. The upper neck dissection can be used as an exploratory measure. For N0 neck patients with supraglottic cancer, comprehensive neck dissection is not invariably performed to avoid overtreatment.

Adult↗

PubMed1998

[Salvage surgery for nasopharyngeal carcinoma after irradiation failure].

OBJECTIVE: To study the salvage surgery for nasopharyngeal carcinoma after irradiation failure. METHODS: One hundred and twenty-one full-dose-irradiation-uncontrolled cases of nasopharyngeal carcinoma had undergone salvage surgery since 1965 till 1992, in which 41 had primary lesion and 80 neck lesion. All patients received radiation before surgery with the dose of 60Gy-145Gy. The patient selection for this report limited to those with recurrent tumors at the primary sites with no apparent bony involvement and no cranial nerve palsy, or cases with resectable neck recurrences. RESULTS: It showed that palatal fenestration was the best choice of approach for recurrent tumors located at the vault of the nasopharyngeal cavity. When the tumor invaded the parapharyngeal space or, owing to the after-effect of radiotherapy, the patient presented with severe occlusion of the mandible, we preferred the lateral approach through partial mandi-bulectomy. The lateral rhinotomy was only indicated for cases with tumor remnant at the posterior nares. Lymph node excision was performed for cases with single movable node on the neck, and RND for the cases with multiple nodes. The complication rate of after surgery was low (10%), considering the heavy dose of irradiation. The three- and five-year survival rate were 49% (59/121) and 38% (38/100) respectively. CONCLUSION: It suggests that the surgery should be considered as a salvage procedure for cases of nasopharyngeal cancer after irradiation failure. Because of high rate of distant metastasis (62 cases or 45% died after surgery), chemotherapy or other measures should be adopted after local treatment.

Adolescent↗