Biomedical subjects

F Zhao

Publications and source records attributed to F Zhao.

At least 109 records · Page 6Linked to original sources

PubMed1997

[The relationship between environmental concentration and exposure concentration in the airborne dust of workplace].

The authors studied the relationship between environmental concentration and exposure concentration in the airborne dust of workplaces, using instantaneous fixed points sampling and personal wear sampling. The results showed that there was a correlation between two kinds of concentrations in the automatic and man-made packing workplaces (r = 0.9914, 0.9977). A relationship between them in the unsteady workplace was found after analysed by one-accumulated generating operation (1-AGO) (r = 0.9945). The samples of environmental and exposure concentrations could be thought from the same normal distribution, that is, the bivariable random sampling in the normal distribution population. Moreover, the exposure concentration could be estimated by environmental one after 1-AGO in the unsteady workplace of airborne dust.

Air Pollutants, Occupational↗

PubMed1997

[Titanium plate reconstruction and fixation system for maxillofacial surgery: a synthetic clinical and experimental investigation].

Titanium plate-screw systems for maxillofacial reconstruction and internal fixation were studied including examination of chemical components, measurement of mechanical natures, biomechanical and biological evaluation, in combination with retrospective analysis of 319 cases fixed by means of plate-screw appliances. The results demonstrated that all experimental data have satisfied basically the design and clinical requirements, with the exception of a weaker curve-resistance and fixative stability of miniplate as well as lower surface wear-resistance of pure titanium. So, further improvement is necessary. Additionally, the function classification and indication of plate-screw systems are discussed. The duration and condition of intermaxillary fixation is suggested. The complications and their causes are analysed through comparison among different fixation systems.

Adolescent↗

PubMed1997

[Treatment of carinal resections for primary pulmonary carcinoma].

Threeteen patients of lung cancer of center type underwent carinal resections in our department from January 1985 to December 1996. There were 3 patients, T3N2M0 and 10 patients, T4N2M0. Palliative resections were performed for 3 patients and radical resections, for 10 patients. Carinal resection with right pneumonectomy was done in 3 patients, part carinal resection with right pneumonectomy 6 patients, part carinal resection with left pneumonectomy 1 case, and part carinal resection with right sleeve upper and middle lobectomy 3 patients. There were no operative complications and deaths. The 3-year survival rate was 54% and the 5-year survival rates, 30%. One patient has survived for 8 years. The satisfied results of operative therapy were followed when no lymph node metastesis in mediastinum and mass could be resected.

Adenocarcinoma↗

PubMed1997

[Experience and lessons of lung transplantation].

In the last 2 years, four hospitals performmed cooperatively single-lung transplantation for 3 patients, 1 left lung and 2 right lung. The patients had pulmonary fibrosis, COPD with cancer or tuberculosis, infection in some extent before transplantation. The patients died from severe infection 9, 48 and 43 days after the operation. We discussed the selection of donors and recipients, operative procedures, postoperative management, especially monitoring, differential diagnosis and treatment of infection and rejection. HLA compatibility and transbronchial lung biopsy were important to the success of lung transplantation. We believe that rejection and infection are important causes of short-term death that should be given more attention.

Graft Rejection↗

PubMed1997

[Study of the relationship between the expression of Ki-67 antigen and the pathobiological behaviours of stomach cancer].

OBJECTIVE: To evaluate the relationship between the expression of Ki-67 antigen and the pathobiological behaviours of stomach cancers especially their distant metastases. METHODS: 56 stomach cancer specimens routinely fixed in formalin and embeded in paraffin (FFEP) were studied by immunohistochemical method. RESULTS: Expression of Ki-67 antigen was significantly related to the distant metastases to liver, ovary and adrenal gland (P < 0.005); but not related to the histological type, growth pattern, depth of invasion, histological differentiation and the metastases to local lymph nodes (P > 0.05). Furthermore, the Ki-67 expression was significantly related to the DNA anueploid pattern and the expression of p53 protein, both of which are closely related to poor prognosis. CONCLUSION: Overexpression of Ki-67 can be used as an objective marker of the proliferative activity for predicting prognosis of stomach cancer and to foretell the high-risk of metastasis of distant organs.

Adenocarcinoma↗

PubMed1997

[Dual-energy separation imaging on an X-ray direct digital imaging system].

A method of dual-energy separation of bone and soft tissue images of chest based on an X-ray direct digital imaging system has been investigated. In this paper, the optimal thickness of the filter for high energy X-ray beam is discussed. An algorithm of correction of scattered radiation is employed before the separation algorithm. The separated images will be shown in the paper. The result shows that it is possible to use an ordinary broad spectral X-ray beam to acquire the dual-energy images for routine X-ray diagnosis.

Humans↗

PubMed1997

[Recombinant AAV-LMP-induced LMP specific cytotoxic response to autologous lymphoblastoid cell lines tranformed by Epstein-Barr virus].

Epstein-Barr virus is believed to be controlled in normal host by virus specific cytotoxic T lymphocytes (CTL). Although unable to eliminate EBV from the body, CTL seems to be essential in control of latently infected cells. Infusion of autologous EBV specific CTL, which can be produced in laboratory by separating lymphocytes from patients and stimulating them with EBV antigen, will provide an effective method of preventing and treating EBV-related diseases. We inserted the LMP gene of EB virus into an AAV vector pACP and packed it in Ad2 infected 293 cells by co-transfecting with plasmid Ad8, which produced the recombinant virus rAAV-LMP. The recombinant virus was used to infect stimulating cells and LMP antigen was expressed on the surface of these cells. Then the stimulating cells were irradiated and co-cultured with T lymphocytes. The EBV specific CTLs were obtained. The target cells were autologous LCLs from EBV-transformed B lymphocytes. The CTL activity was assayed by BLT activity method. The result indicated that all the four CTL strains could recognize and kill their target cells. This study has laid the technical basis for us to prevent and treat nasopharyngeal carcinoma in China with molecular biological methods.

Cell Line↗

PubMed1997

[Immunologically prepared plasma specimen of albuterol for high performance liquid chromatographic determination].

Immune-affinity method for preparation of sample in plasma is reported in this paper. Albuterol was coupled to bovine serum albumin (BSA) to prepare the antigen and immunized in rabbit to produce the anti-albuterol serum (immune globulin). The anti-albuterol serum was treated with saturated ammonium sulfate solution to obtain the antibody (immune globulin). The antibody was coupled with Sepharose 4B to prepare the immune globulin-affinity column. The plasma containing albuterol was introduced into the column and was rinsed in turn with phosphate buffer and water, and then eluted with methanol. After being concenfrated the sample was analyzed by HPLC with a sillica column (4.6 mm x 200 mm, 5 microm), a mixture of methanol: 2 mol/L ammonium acetate (99.5 : 0.5) as mobile phase with a flow rate of 1.2 mL/min, and fluorecence detector monitoring at lambdaex = 226 nm and lambdaem = 306 nm. The results showed that the immune globulin-affinity column has the characteristic of high purity and high specificity, and it is suitable for the preparation of chromatographic plasma specimen to determine albuterol in plasma. The relationship between peak area ratios and concentration from 2 to 80 microg/L were linear (r=0.998). The extraction recoveries from plasma at concentrations of 2-80 microg/L were 98.8% +/- 7.3%. The RSD for intra-day (n=5) was 5.8% and that for inter-day assay (n=5) was 7.8%.

Albuterol↗

PubMed1997

Electrochemical treatment of lung cancer.

A pilot study of electrochemical treatment (ECT) as a therapy for 386 patients with nonsmall cell lung cancer was undertaken. There were 103 stage II cases, 89 stage IIIa cases, 122 stage IIIb cases, and 72 stage IV cases. Two ECT methods were used: For peripherally located lung cancer, platinum electrodes were inserted transcutaneously into the tumor under x-ray or CT guidance. For central type lung cancer or for those inoperable during thoracotomy, electrodes were inserted intraoperatively directly into the cancer. Voltage was 6-8 V, current was 40-100 mA, and electric charge was 100 coulombs per cm of tumor diameter. The number of electrodes was determined from the size of cancer mass, because the diameter of effective area around each electrode is approximately 3 cm. The short-term (6 months after ECT) results of the 386 lung cancer cases were: complete response (CR), 25.6% (99/386); partial response (PR), 46.4% (179/386); no change (NC), 15.3% (59/386); and progressive disease (PD), 12.7% (49/386). The total effective rate (CR + PR) was 72% (278/386). The 1, 3, and 5 year overall survival rates were 86.3% (333/386), 58.8% (227/386), and 29.5% (114/386), respectively. The main complication was traumatic pneumothorax, with an incidence rate of 14.8% (57/386). These clinical results show that ECT is simple, safe, effective, and minimally traumatic. ECT provides an alternative method for treating lung cancers that are conventionally inoperable, that are not responsive to chemotherapy or radiotherapy, or that cannot be resected after thoracotomy. Long-term survival rates suggest that ECT warrants further investigation.

Adult↗

PubMed1997

STEP: a family of brain-enriched PTPs. Alternative splicing produces transmembrane, cytosolic and truncated isoforms.

The family of striatal enriched phosphatases (STEPs) consists of protein tyrosine phosphatases (PTPs) that are enriched within the central nervous system. Previous biochemical studies have shown that the STEP family includes transmembrane, as well as soluble, cytosolic proteins. We now extend these findings with the isolation and characterization of a new, truncated member of this family, termed STEP38. The cDNA of STEP38 encodes a protein of 346 amino acids with a predicted mobility of 38 kDa. In contrast to the cytosolic variants, it contains two hydrophobic amino acid sequences at its N-terminus, two sequences enriched in Pro, Glu, Asp, Ser and Thr residues (PEST sequences), and two polyproline domains. We have used differential centrifugation, continuous sucrose gradients, and transfection experiments to clarify the subcellular localization of STEP38 within membrane compartments. These experiments suggest that a pool of STEP38 is targeted to membrane compartments of the endoplasmic reticulum. The STEP38 cDNA contains a stop codon upstream of the catalytic phosphatase domain that is normally present in other STEP variants, and enzymatic assays conform that STEP38 is inactive. Thus, the STEP family consists of cytosolic, transmembrane, and truncated isoforms. These findings are similar to what has been found for some members of the protein tyrosine kinase (PTK) family that uses alternative splicing mechanisms to produce active and inactive variants. By analogy with suggested mechanisms of action for the truncated PTKs, inactive STEP isoforms may participate in signaling events by protecting potential substrates from dephosphorylation by other members of this family.

Alternative Splicing↗

PubMed1997

Effectiveness of electrochemical therapy in the treatment of lung cancers of middle and late stage.

OBJECTIVE: To investigate the effect of electrochemical therapy (ECT) in the treatment of middle and late-stage lung cancers. METHODS: Three hundred and eighty-six cases (287 males md 99 females aged 25-78, with an average age of 51 years) with middle and late-stage lung cancers were treated with ECT. Two hundred and three patients had squamous cell carcinoma, 138 adenocarcinoma and 45 undifferentiated cancer. Diameters of the cancers were respectively 4.0-6.0 cm in 153 cases, 6.1-8.0 cm in 82 cases, 8.1-10.0 cm in 102 cases and over 10.0 cm in 49 cases. In this group, none was at stage I, 103 cases were at stage II, 89 cases at IIIa, 122 cases at IIIb and 72 cases IV. Of the 386 cases, 152 cases (39.4%) also suffered from hypertension, heart disease etc. Anode and cathode platinum electrodes were inserted accurately into the tumour mass. Distance between two electrodes was 2.0-2.5 cm. Electrodes were connected to a special ECT instrument. The current was maintained at 6-8 V and 80-100 mA. One hundred coulombs are used for treating 1 cm diameter of tumour mass. RESULTS: Of the 386 cases, 99 cases (25.6%) achieved complete remission (CR). 179 cases (46.4%) achieved partial remission (PR), 59 cases (15.3%) had no change (NC) and 49 cases (12.7%) had progression of disease (PD). Effective rate CR + PR) was 72% (278 cases). One to five year survival rates were 86.3%, 76.4%, 58.8%, 39.9% and 29.5%, respectively. CONCLUSIONS: ECT is easy to use. It is effective, safe, less traumatic and makes patients recover quickly. This is a new and effective method to treat patients with tumours who are inoperable and can not receive chemotherapy or radiotherapy.

Adenocarcinoma↗

PubMed1996

STEP61: a member of a family of brain-enriched PTPs is localized to the endoplasmic reticulum.

The STEP family of protein tyrosine phosphatases is highly enriched within the CNS. Members of this family are alternatively spliced to produce both transmembrane and cytosolic variants. This manuscript describes the distinctive intracellular distribution and enzymatic activity of the membrane-associated isoform STEP61. Transfection experiments in fibroblasts, as well as subcellular fractionations, sucrose density gradients, immunocytochemical labeling, and electron microscopy in brain tissue, show that STEP61 is an intrinsic membrane protein of striatal neurons and is associated with the endoplasmic reticulum. In addition, structural analysis of the novel N-terminal region of STEP61 reveals several motifs not present in the cytosolic variant STEP46. These include two putative transmembrane domains, two sequences rich in Pro, Glu, Asp, Ser, and Thr (PEST sequences), and two polyproline-rich domains. Like STEP46, STEP61 is enriched in the brain, but the recombinant protein has less enzymatic activity than STEP46. Because STEP46 is contained in its entirety within STEP61 and differs only in the extended N terminus of STEP61, this amino acid sequence is responsible for the association of STEP61 with membrane compartments and may also regulate its enzymatic activity.

Amino Acid Sequence↗

PubMed1996

Effects of polyaminocarboxylate metal chelators on iron-thiolate induced oxidation of methionine- and histidine-containing peptides.

PURPOSE: Site-specific protein oxidation induced by prooxidant/metal/ oxygen has been recognized as one of the major degradation pathways of protein pharmaceuticals. Polyaminocarboxylate (PAC) metal chelators are commonly employed to prevent metal-catalyzed oxidation, for they sequester metals. However, studies have indicated that iron chelates may still be catalytically active due to their specific coordination geometry. The purpose of this study was to investigate how PAC chelators affect prooxidant/metal/oxygen-catalyzed oxidation of peptides containing histidine (His) and methionine (Met). METHODS: PACs were applied to a model oxidizing system, dithiothreitol/iron/oxygen, which was shown to promote the oxidation of Met to Met sulfoxide in the two model peptides, GGGMGGG and GHGMGGG. RESULTS: PAC chelators did not suppress the peptide oxidation but significantly changed the product pattern. In particular, the yield of Met sulfoxide dropped significantly, while a number of other products emerged, including oxidation products from the N-terminus and His (if present). Overall, the oxidation became rather non-selective in the presence of PACs. The oxidation kinetics were significantly accelerated by nitrilotriacetate (NTA), ethylenediaminediacetate (EDDA), and ethylenediaminetetraacetate (EDTA), but they were slowed down by ethyl-enebis(oxyethylenenitrilo)tetraacetate (EGTA) and diethylenetri-aminepentaacetate (DTPA). Meanwhile the PAC chelators were also observed to undergo degradation. Scavengers of hydrogen peroxide or hydroxyl radicals exerted only partial inhibition on the peptide oxidation. CONCLUSIONS: The results of this study are rationalized by the abilities of PAC chelators (i) to extract iron from potential binding sites of the peptides to impair site-specific oxidation, and (ii) to promote the formation of ROS different from the species formed at the peptide metal-binding sites.

Ammonia↗

PubMed1996

Hearing impairment: special needs of the elderly.

Within this paper we have considered some of the particular disabilities and handicaps commonly experienced by elderly hearing-impaired people as compared with younger individuals. We examined their ratings of their disability and handicap and found that both disability and handicap increased more rapidly with increasing hearing loss in younger than in older patients. We have finally considered the strategies used by older people to cope with hearing loss and found them more likely to withdraw from difficult listening situations or to interrupt the speaker, but less likely to position themselves to hear better.

Aged↗

PubMed1996

Determinants of speech-hearing disability in King-Kopetzky syndrome.

King-Kopetzky syndrome is characterized by auditory disability with a clinically normal hearing threshold. The main reported disability is hearing speech in the presence of background noise. The degrees of speech-hearing disability in patients with King-Kopetzky syndrome have been investigated with the use of the Social Hearing Handicap Index (SHHI), and the relationships between the SHHI scores and a number of physiological, psychoacoustical and psychological factors determined in 109 patients. The significantly higher (worse) SHHI scores in patients with King-Kopetzky syndrome indicate that this group suffer a considerable degree of speech-hearing disability. In our study, the main findings are that some psychological factors, performance of the sentence in noise test and auditory thresholds are significantly correlated with the SHHI scores. We were unable to find any relationships between the SHHI and frequency resolution or EOAEs. In a multiple stepwise regression, somatic anxiety and the performance of the sentence in noise test are the significant predictors of SHHI scores. These two variables appear to be the main determinants of speech-hearing disability in King-Kopetzky syndrome.

Adolescent↗

PubMed1996

Hearing complaints of patients with King-Kopetzky syndrome (obscure auditory dysfunction).

The hearing complaints in patients with King-Kopetzky syndrome were studied by use of the open-ended hearing problem questionnaire. The main findings are that complaints were commonly focused on the categories of 'live speech' and 'electronic speech' difficulties in patients with King-Kopetzky syndrome, particularly the auditory difficulties of speech in noise and group conversation. However, they reported problems with warning signals significantly less frequently than a control 'audiological rehabilitation' group and the patients studied by Barcham and Stephens (1980). In addition, main psychological problems were related to anxiety (e.g. irritability, nervousness and moodiness) in patients with King-Kopetzky syndrome. The open-ended hearing problem questionnaire appears to be a useful tool that can be used to high-light the speech hearing disability encountered by patients with King-Kopetzky syndrome.

Adolescent↗

PubMed1996

[A study on DNA content and cell cycle phase analysis in endometrial carcinoma].

OBJECTIVE: To study the prognostic value of DNA content, cell cycle phase in endometrial carcinoma. METHODS: DNA content and cell cycle phase analysis were performed on 100 paraffin-embedded archival specimens from 103 cases of endometrial carcinoma using flow cytometry. RESULTS: Aneuploidy was found in 71.0% of specimens. The aneuploidy rate in specimens from grade III, deep myometrial invasion and stage III, IV was significantly higher than that in specimens from grade I, nonmyometrial invasion and stage I (P < 0.05 respectively). 5-year survival rate for patients with aneuploidy was 65.9% and for patients with diploidy was 87.6% (P < 0.01). High S-phase fraction (SPF) was associated with high grade, deep myometrial invasion and advanced stage. The mean SPF was 13.4% in the living group and 17% in the dead group. The 5-year survival rate for patients with SPF > 17% was 50.4% and for patients with SPF < 17% was 79.1% (P < 0.01). SPF and stage were the most important prognostic factors in endometrial carcinoma by Cox's proportional hazards model. CONCLUSIONS: DNA ploidy and SPF were found to be of important prognostic indicators in endometrial carcinoma.

Adenocarcinoma↗

PubMed1996

[Detection of lipoarabinomannan-IgG in serum for the diagnosis of pulmonary tuberculosis].

OBJECTIVE: To ascertain the value of lipoarabinomannan-IgG (LAM-IgG) determination in the diagnosis of pulmonary tuberculosis. METHOD: LAM-IgG in sera obtained from 90 patients with active pulmonary tuberculosis, 53 patients with lung cancer and 30 healthy individuals were detected by using rapid enzyme-linked immunosorbent assay (ELISA). RESULTS: The positive rate was 82% in tuberculosis group, and the false positive rates were 8% and 3% in cancer group and healthy controls respectively. CONCLUSION: The results suggested that rapid ELISA and LAM-IgG detection was a useful supplementary tool for diagnosis of pulmonary tuberculosis.

Enzyme-Linked Immunosorbent Assay↗