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Biomedical subjects

D Han

Publications and source records attributed to D Han.

At least 91 records · Page 5Linked to original sources
PubMed1999

[Clinical study of capsaicin in the treatment of allergic rhinitis].

OBJECTIVE: To study the clinical effect of capsaicin of nasal administration in 100 cases of allergic rhinitis. METHOD: Capsaicin was applied by nostril, once 5 days and 5 times as a therapeutic course. Acidophil were measured and nasal airflow resistance was analysed before and after capsaicin therapy. RESULT: It showed that nasal symptoms of patients were obviously relieved and 94% of the cases in the measure of acidophil changed to negative from positive. Moreover, capsaicin induced decrease in nasal airflow resistance from (0.6272 +/- 0.3534) kPa.s/L before therapy to (0.4057 +/- 0.2419) kPa.s/L after therapy (P < 0.001). 90 cases of 100 patients were fellowed up one year, the total effective rate was 89%. CONCLUSION: Our study suggests that capsaicin possessed remarkable effects in the treatment of allergic rhinitis; analyse of nasal airflow resistance may be used as one of the objective guideline in the determinant of therapeutic effects.

Administration, Intranasal↗
PubMed1999

[Ectopic meningiomas of the head and neck (report of 10 cases)].

OBJECTIVE: To study the diagnosis and treatment of ectopic meningiomas of the head and neck. METHOD: A retrospective review was made of 10 patients with ectopic meningiomas of the head and neck, the pathological diagnosis was as follows: 2 case epithelial type, 2 case psammomatous type, 1 case transitional type, 1 case malignant meningioma and types of another 4 cases were unknown. RESULT: All patients were treated surgically, 4 patients with local recurrence were operated secondarily and no signs were observed with the follow-up of many years. CONCLUSION: Surgery was the choice of ectopic meningiomas of the head and neck.

Adolescent↗
PubMed1999

[Local treatment with human laryngeal squamous carcinoma draining lymph node lymphocytes in nude mice bearing human laryngeal carcinoma xenografts].

OBJECTIVE: To increase the number of the tumor draining lymph nodes lymphocytes (TDLNLs) in tumor site and study its anti-tumor effect. METHODS: Interleukin 2-activated TDLNLs were administrated by local injection in 10 nude mice bearing human laryngeal cancer at 10(7) cells/mouse, once a week for two weeks. As a control, 10 nude mice bearing human laryngeal cancer were injected with D-Hanks buffer solution. RESULTS: The volume and weight of TDLNLs treated tumors were significantly reduced in comparison with those of the control (P < 0.05). The observed histopathologic characteristics of treated tumors were tumor necrotic foci and increased infiltration of lymphocytes in tumor and around tumor vessels. Proliferation of spleen nodules was also observed in the treatment group. Remote metastasis was not found in this group. In contrast with the control group, tumor necrosis and proliferation of spleen nodules were not observed and infiltration of lymphocytes in the tumor was not significant. There was a lung metastasis in the control group. CONCLUSION: Local injection of TDLNLs is effective against human laryngeal carcinoma xenografts in nude mice. It also could stimulate the immunoresponse of hosts and probably decrease the chance of tumor metastasis.

Animals↗
PubMed1999

[Immunohistochemical and pathological study of capsaicin in the treatment of rabbit animal model with allergic rhinitis].

OBJECTIVE: To determine the desensitization effect of capsaicin. METHODS: Toluene-2,4-diisocyanate(TDI) sensitized white rabbits used as animal models of allergic rhinitis were treated with capsaicin. At the end of treatment, the changes in the nasal mucosa were studied by immunohistochemical and pathological methods. RESULTS: Our results showed that the symptoms of allergic rhinitis were remarkably relieved after capsaicin treatment. Immunohistochemical study revealed that substance P immunoreactive fibers in the nasal mucosa showed a marked decrease after capasicin application, but the density and number of SP-IR fibers were significantly increased in the control group. Hematoxylin and eosin staining demonstrated that no edema was found in the nasal mucosa and small vessels were normal after capsaicin application, but edema, vasodilation and inflammatory cell infiltration were discovered in the control group. CONCLUSION: The results suggested that local capsaicin treatment was a selective, and non-traumatic method to induce a long lasting desensitization of the nasal mucosa, to alleviate nasal congestion, rhinorrhea and sneezing, and to reduce the sensory neuron sensitivity of the mucosa.

Administration, Intranasal↗
PubMed1999

[Bilateral acoustic neuromas].

OBJECTIVE: To investigate the clinical course, growth character and treatment of bilateral acoustic neuromas (BANs). METHODS: Five cases of BANs were reported. RESULTS: From 1986 to 1996, 92 patients with acoustic tumors were managed. Of them, 5(5%) bilateral acoustic neuromas were observed. All patients were males, the age at the time of testing ranged from 16 to 31 years (mean 23.8 years). In all patients, progressive hearing loss and tinnitus were the most common initial symptoms. In addition, signs of other cranial nerve deficits were detected in all patients. Two cases had cafe au lait spots and all cases had neurofibromas of varying sizes and shapes in subcutaneous tissues. Four had unilateral acoustic tumors operated on, one by the translabyrinthine approach, 3 by the suboccipital approach. One patient died due to encephaledema and hernia of brain after operation. According to the MRI data in one case, the average growth rate of acoustic tumor was 1.1 cm (superior/inferior) and 0.7 cm (medical/lateral) per year. CONCLUSION: The management of BANs patients presents challenging problems different from the unilateral acoustic tumors.

Adolescent↗
PubMed1999

[Diagnosis and surgical treatment of meningoencephalocele].

OBJECTIVE: To explore the characteristics of symptoms of meningoencephalocele and the selection of the most appropriate surgical approach. METHODS: From January 1986 to August 1997, 11 cases (frontoethmoidal type 5, basal 5, occipital 1) were retrospectively analyzed. RESULTS: Combined intraextracranial approach was applied 11 times and successful in 10 times; simple frontal approach 1 time, unsuccessful, lateral nasal incision 2 times, failed in 1. No recurrence was found in all successful operations during follow-up. CONCLUSION: Combined intra-extracranial approach, which provides excellent exposure and convenient repairing of skull base deficit is an ideal operation for meningoencephalocele.

Adolescent↗
PubMed1999

[Immunohistochemical evaluation of micrometastases to cervical lymph nodes in supraglottic cancer].

OBJECTIVE: Supraglottic carcinomas of larynx tends to metastasize to cervical lymph nodes. The regular pathological method of diagnosis is easy to have the micrometastasis missed, and serial-sectioning is too difficult be used in the regular pathological examinations. The aim of this study was to evaluate the value of immunohistochemical assay in the detection of micrometastasis. METHODS: Monoclonal antibodies against cytokeratin (AE1/AE3) were used to detect the cervical lymph nodes of 46 cases (50 sides of neck) of supraglottic carcinoma with pathologically negative findings (pN0). RESULTS: Micrometastases were identified in 13 lymph nodes of 11 cases. CONCLUSION: It is suggested that the detection of lymph node micrometastases with immunohistochemical method is more sensitive than that of regular pathologic method. It is comparable to serial sectioning. Therefore, It is a valuable clinical method to detect the early lymph node metastasis.

Adult↗
PubMed1999

[Congenital atresia of the external auditory canal].

OBJECTIVE: To investigate the clinical characters and treatments of congenital aural atresia. METHODS: From 1986 to 1996, 44 patients (50 ears) with congenital aural atresias were operated in the ENT Department of the PLA General Hospital. Postoperative audiological follow-up ranged from 6 months to 9 years. RESULTS: Ossicular chain anomalies were presented in all cases. This consisted most frequently of fusion (54%) or deficiency (36%) of the malleus and the incus with or without fusion to the tympanic wall. Facial nerve abnormalities were seen in 16 ears (32%). After the operation, hearing improvement was found in 33 ears (66%), in which 13 ears (26%) had hearing improvement (pure tone threshold) up to 40 dB. The postoperative complications were external auditory canal stenosis, lateralization of the tympanic membrane and recurrent infections of the cavity and canal skin, with incidences of 34%, 18% and 14%, respectively. CONCLUSION: Maintenance of width of the aural canal and prevention of lateral healing of the transplantated tympanic membrane were crucial in the treatment of congenital aural atresia.

Adolescent↗
PubMed1998

Promoter analysis of the Drosophila genes encoding TFIIB and TATA box-binding protein.

We have analyzed the 5'-flanking regions of the Drosophila genes encoding the TFIIB and TATA box-binding proteins (TBP) and mapped the regulatory regions required for their efficient expression. We found that the 500 bp long region (-439 to +60) and the 401 bp long region (-261 to +138) are required for the efficient expression of TFIIB and TBP genes, respectively. In the TFIIB promoter region, the upstream DNA between -439 and -280 and the downstream DNA between +8 and +60 are necessary for the stimulation of promoter activity. The upstream DNA between -439 and -280 stimulates transcription in an orientation dependent manner. In the TBP promoter region, the upstream DNA between -261 and -207, and the downstream DNA between +15 and +138 are necessary for the stimulation of promoter activity. The upstream DNA (-261 to -207) required for TBP promoter activity contains a 11 bp long palindromic sequence and a DNA replication-related element sequence. Particularly, we could find that the downstream promoter regions of TFIIB and TBP genes contain the conserved nucleotide sequences, suggesting the presence of a common regulatory mechanism for the expression of these two genes.

Animals↗
PubMed1998

A comparative molecular analysis of four rat smooth muscle cell lines.

Transcriptional regulation of smooth muscle cell (SMC) differentiation is a rapidly growing area of interest that has relevance for understanding intimal disease. Despite the wealth of data accumulating in vitro, however, no study has compared the cell-specific marker profile, transfectability, promoter activity, and growth characteristics among several SMC culture systems. Accordingly, we performed a comprehensive analysis of the marker profile, growth properties, transfectability, and SMC promoter activity in four rat SMC lines (A7r5, adult and pup aortic, and PAC1). Despite alterations in chromosomal number and structure, A7r5, adult aortic, and PAC1 cells express all SMC markers studied including SM alpha-actin, SM calponin, SM22, tropoelastin, and to a lesser extent, SM myosin heavy chain (SMMHC). In contrast, pup aortic cells express very low or undetectable levels of all the above markers except tropoelastin. Adult aortic, pup, and PAC1 cells display similar growth curves and levels of proto-oncogene transcripts, whereas those in the A7r5 line are comparatively less. All cell lines studied except pup cells show expression of SMC differentiation genes during active growth, indicating that growth and differentiation are not mutually exclusive in cultured smooth muscle. Transfection studies reveal dramatic differences in DNA uptake and SMC-restricted promoter activity between cell lines. Collectively, these results provide detailed information relating to SMC molecular biology in culture that should facilitate the selection of a cell line for studying the transcriptional regulatory mechanisms underlying SMC differentiation.

Actins↗
PubMed1998

Vitamin E reduces oxidant injury to mitochondria and the hepatotoxicity of taurochenodeoxycholic acid in the rat.

BACKGROUND & AIMS: Hydrophobic bile acids have been implicated in the pathogenesis of cholestatic liver injury. The hypothesis that hydrophobic bile acid toxicity is mediated by oxidant stress in an in vivo rat model was tested in this study. METHODS: A dose-response study of bolus intravenous (i.v.) taurochenodeoxycholic acid (TCDC) in rats was conducted. Rats were then pretreated with parenteral alpha-tocopherol, and its effect on i.v. TCDC toxicity was evaluated by liver blood tests and by assessing mitochondrial lipid peroxidation. RESULTS: Four hours after an i.v. bolus of TCDC (10 mumol/100 g weight), serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels peaked, hepatic mitochondria showed evidence of increased lipid peroxidation, and serum bile acid analysis was consistent with a cholestatic injury. Liver histology at 4 hours showed hepatocellular necrosis and swelling and mild portal tract inflammation. Treatment with parenteral alpha-tocopherol was associated with a 60%-70% reduction in AST and ALT levels, improved histology, and a 60% reduction in mitochondrial lipid peroxidation in rats receiving TCDC. CONCLUSIONS: These data show that hepatocyte injury and oxidant damage to mitochondria caused by i.v. TCDC can be significantly reduced by pretreatment with the antioxidant vitamin E. These in vivo findings support the role for oxidant stress in the pathogenesis of bile acid hepatic toxicity.

Animals↗
PubMed1998

Topical application of alpha-tocopherol modulates the antioxidant network and diminishes ultraviolet-induced oxidative damage in murine skin.

The aim of this study was to investigate the effects of topical alpha-tocopherol application on epidermal and dermal antioxidants and its ability to prevent ultraviolet (UV)-induced oxidative damage. Hairless mice received topical applications of alpha-tocopherol 24 h before a single, acute UV irradiation (10 x minimal erythemal dose). The four major antioxidant enzymes (catalase, superoxide dismutase, glutathione reductase and glutathione peroxidase), hydrophilic and lipophilic antioxidants, and lipid hydroperoxides, markers of oxidative damage, were assayed in both epidermis and dermis of hairless mice. Topical alpha-tocopherol treatment increased dermal superoxide dismutase activity by 30% (P < 0.01) and protected epidermal glutathione peroxidase and superoxide dismutase from depletion after UV irradiation. Total and reduced glutathione levels in the epidermis increased by 50% after the topical treatment (P < 0.05), as did dermal ascorbate levels (by 40%: P < 0.01). The topical treatment increased alpha-tocopherol levels both in the epidermis (62-fold) and the dermis (22-fold: P < 0.001 in each layer). Furthermore, alpha-tocopherol treatment significantly reduced the formation of epidermal lipid hydroperoxides after UV irradiation (P < 0.05). These results demonstrate that topical administration of alpha-tocopherol protects cutaneous tissues against oxidative damage induced by UV irradiation in vivo, and suggest that the underlying mechanism of this effect involves the up-regulation of a network of enzymatic and non-enzymatic antioxidants.

Administration, Cutaneous↗
PubMed1998

Half-dose gadolinium-enhanced MR imaging with magnetization transfer technique in brain tumors: comparison with conventional contrast-enhanced MR imaging.

OBJECTIVE: The purpose of this study was to determine whether half-dose enhanced MR imaging with magnetization transfer (MT) saturation can replace standard-dose enhanced MR imaging without MT saturation in patients who have brain tumors. SUBJECTS AND METHODS: Three sets of enhanced T1-weighted MR images were prospectively obtained for each of 25 patients with 32 brain tumors; the first conventional MR images without MT were obtained after administration of standard-dose (0.1-mmol/kg) gadopentetate dimeglumine. Within 1 week, patients underwent administration of one half-dose (0.05 mmol/kg) of the contrast medium, and then two sets of enhanced T1-weighted images were obtained with and then without MT. The degree of contrast enhancement was assessed qualitatively for all 32 tumors and quantitatively for 26 tumors. In the quantitative analysis, we compared mean values for tumor-brain contrast-to-noise ratios in three sets of images. RESULTS: The visual conspicuity of enhancing lesions in half-dose T1-weighted MR images with MT was comparable with that of standard-dose conventional T1-weighted MR images in 43% of cases including most extraaxial tumors. In approximately 75% of cases, the degree of enhancement of the lesions was similar for half-dose T1-weighted images obtained with and without MT. Overall, mean values for tumor-brain contrast-to-noise ratios were significantly lower in half-dose T1-weighted images with MT than in standard-dose T1-weighted images. Also, mean values for tumor-brain contrast-to-noise ratios were significantly higher in half-dose T1-weighted images with MT than in half-dose T1-weighted images without MT. CONCLUSION: Because half-dose enhanced MR imaging with MT yields enhancement comparable with that of standard-dose enhanced conventional MR imaging in less than 50% of cases, the former technique would replace the latter in only limited cases such as selected extraaxial tumors.

Adult↗
PubMed1998

A case of type IIa early gastric cancer developed in pernicious anemia.

Pernicious anemia is an autoimmune disease characterized by a gastric mucosal defect which results in an insufficiency of intrinsic factor to facilitate the absorption of the physiologic amount of cobalamin. Increased risk of cancers of the stomach has been reported for patients with pernicious anemia. We report here a case of a 65 year old woman who had been diagnosed as having pernicious anemia 16 months previously, was receiving monthly vitamin B12 injections, and developed early gastric cancer type IIa by routine follow-up gastroscopic examination. This patient underwent endoscopic mucosal resection for an early gastric cancer lesion with a free resection margin.

Aged↗