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Biomedical subjects

Z Huang

Publications and source records attributed to Z Huang.

At least 325 records · Page 18Linked to original sources
PubMed1997

Strain-related differences in susceptibility to transient forebrain ischemia in SV-129 and C57black/6 mice.

BACKGROUND AND PURPOSE: We explored susceptibility to injury after global ischemia in SV-129 and C57Black/6 mice, two commonly used-background strains in genetically engineered mice. METHODS: Mice (n = 84) were subjected to 15, 30, or 75 minutes of bilateral common carotid artery (BCCA) occlusion followed by reperfusion for 72 hours. BCCA occlusion was performed under halothane or chloral hydrate anesthesia, in one experiment, mean arterial blood pressure and regional cerebral blood flow (laser Doppler flowmetry) were matched by controlled exsanguination. Baseline absolute blood flow measurements were obtained in both strains using a tracer, N-isopropyl-[methyl 1,3-14C]-p-iodoamphetamine, indicator fractionation technique (n = 5 per group). Vascular anatomy of the circle of Willis was visualized by intravascular perfusion of carbon black ink (n = 10 per group). Cerebrovascular reactivity was assessed by measuring the diameter of pial vessels (intravital microscopy) to acetylcholine (ACh) superfusion (0.1 to 10 mmol/L) in a closed cranial window preparation (n = 29). RESULTS: Resting blood flow values did not differ between groups in striatum, cerebellum, and brain-stem regions. SV-129 mice were less susceptible than C57Black/6 mice to ischemic injury (0.0 +/- 0.0 versus 1.3 +/- 0.3 damage in hippocampal CA1 region after 30 minutes of ischemia in SV-129 and C57Black/6, respectively; P < .01). Cellular damage (grade 1 to 3 injury) comparable to 30-minute BCCA occlusion was achieved only after 75 minutes of ischemia in SV-129 mice (1.1 +/- 0.3). Ischemic damage was also significantly less in SV-129 mice after blood pressure and flow were matched during ischemia in halothane-anesthetized SV-129 mice (0.5 +/- 0.3 versus 1.4 +/- 0.2, P < .05), or after chloral hydrate anesthesia (0.4 +/- 0.2 versus 1.5 +/- 0.4, P < .05). Hypoplastic posterior communicating arteries were found in all 10 C57Black/6 mice and may explain the greater susceptibility of these mice to injury after BCCA occlusion. More robust vasodilation to ACh in C57Black/6 mice could also indicate genetic differences in responses to vasoactive substances. CONCLUSIONS: C57Black/6 mice exhibit enhanced susceptibility to global cerebral ischemic injury, an incompletely formed circle of Willis, and augmented pial vessel dilation to ACh compared with SV-129 mice. Our findings suggest that strain differences may confound results when genetically engineered mice generated from more than a single background strain are used.

Acetylcholine↗
PubMed1997

Effect of sialodacryoadenitis virus exposure on acinar epithelial cells from the rat lacrimal gland.

Sialodacryoadenitis virus (SDAV), a RNA coronavirus, induces degenerative, necrotic and atrophic alterations in acinar epithelial cells of the rat lacrimal gland. To begin to explore the underlying mechanism(s) of this viral effect, we sought in the present study to: (1) determine whether SDAV invades and replicates in lacrimal gland acinar cells in vitro and (2) assess whether short-term SDAV challenge interferes with the viability or function of acinar cells in vitro. For comparison we also evaluated the relative infectivity of SDAV in acinar epithelial cells from lacrimal, submandibular and parotid glands, given that salivary tissues are known to be highly susceptible to SDAV infection in vivo. Acinar epithelial cells from lacrimal, submandibular or parotid glands were isolated from male rats, exposed briefly to SDAV or control cell antigen and then cultured for four, eight or twelve days. At experimental termination, SDAV titers in both media and sonicated cell extracts were evaluated by plaque assay titration on mouse L2 cell monolayers. To evaluate functional aspects of lacrimal gland acinar cells, SDAV-infected cells were incubated in the presence or absence of dihydrotestosterone and culture media were analyzed by RIA to measure the extent of the androgen-induced increase in secretory component (SC) production. Our results showed that: (1) SDAV invades and replicates in lacrimal gland acinar cells, Viral challenge resulted in a significant, time-dependent increase in SDAV titers, that were primarily cell-associated and greatly exceeded amounts contained in the original inoculum; (2) SDAV infection did not compromise lacrimal acinar cell viability or prevent the cellular SC response to androgens. Viral presence, though, did often attenuate the magnitude of this hormone action; and (3) SDAV infects salivary acinar cells, but the kinetics and magnitude or viral replication in lacrimal, submandibular and parotid cells showed considerable variations. These findings demonstrate that SDAV invades and replicates in acinar epithelial cells from lacrimal and salivary glands. The resulting release of infectious progeny may play a role in the SDAV-induced pathology of exocrine tissues in vivo.

Animals↗
PubMed1997

[Clinical study of bioactive glass ceramics as orbital implants].

One hundred and two patients received a bioactive glass ceramics as an orbital implant of 98 cases 96.1% were successful after operation. Of 4 cases that underwent operation, conjunctiva was torn partly when stitches were taken out of the wound. One out of four had to remove the orbital implant. After a follow-up of 6 months to 2 years, there were no complications. All patients were satisfied with their cosmetic appearance and motility although drilling of the motility hole as a secondary procedure was not peformed.

Adolescent↗
PubMed1997

[Influence of locus coeruleus stimulation on the vagal-cardiovascular reflex].

Experiments were performed on 36 anesthetized rabbits. By cervical vagal afferent stimulation (VAS) with lower electric frequency (5-8 Hz) and higher electric frequency (50-100 Hz), the depressor and pressor responses were established. Both of these responses accompanied by decreasing in renal sympathetic activity (RSA). With the parameters of vagal-pressure reflex and vagal-sympathetic stimulation reflex, effects of stimulation of the locus coeruleus on these were investigated. The vagal-pressure and sympathetic reflexes were significantly inhibited by electric and chemical (glutamate) stimulation of the locus coeruleus. Meanwhile both the electric and chemical stimulation of the locus coeruleus per se elicited the elevation of BP and RSA. These results together with the recently hypothesized global function of the locus coeruleus were discussed.

Animals↗
PubMed1997

[The usage of allograft nasal septal cartilage in partial laryngectomy].

Based on the experiment of five dogs, 22 cases of laryngeal carcinoma using allograft nasal septal cartilage as a framework for laryngeal defect after partial larygectomy are reported. After 5 years follow-up, the functions of phonation and respiration of 17 cases were satisfying and their phonatic loudness was raised remarkably. The method was used mainly for patients with T1 glottic carcinoma involving anterion commissure and selective T2, T3 glottic carcinoma. The advantages of allograft nasal septal cartilage in partial laryngectomy are discussed in comparison with auto nasal mucoseptal graft.

Aged↗
PubMed1997

[Experimental study of vascular gene transfer using soluble stent].

We assessed the possibility of gene transfer into anastomotic arteries in vivo using soluble stent containing Adv5-CMV/LacZ. After being soaked in a high concentration solution of glucose containing Adv5-CMV (control group) or Adv5-CMV/LacZ (treatment group) for 30 minutes, we inserted soluble stents into the lumina of cut rat carotid arteries, and end-to-end anastomoses of cut rat carotid were performed with standard microvascular surgical technique. 16 rats were killed after two weeks, the segments of anastomotic carotid arteries were prepared for assessing beta-galactosidase activity and histochemical staining. In the control group, the anastomotic arteries did not have detectable level of beta-galactosidase expression. In the treatment group, the amount of beta-galactosidase expression was 9.80 x 10-3 u/g tissue. Microscopic examination of histochemically stained arteries demonstrated that gene transfered not only to endothelial cells but also to smooth muscle cells, and all anastomotic arteries were transfered in the treatment group, but none of arteries revealed blue in the control group. The results of this experimental study suggested that soluble stent be a new method of direct gene transfer into arteries in vivo.

Anastomosis, Surgical↗
PubMed1997

[Determination of basic drugs in blood by RP-HPLC].

A reversed-phase HPLC method for determination of phenothiazines and tricyclin antidepressants in whole blood was described. In this paper, a model 1090 HPLC with DAD and a zorbax ODS column was used. The mobile phase was methanol: water: tritely amine (75:24.7:0.3) with pH 7.5. Cyproheptadine was used as internal standard in this method. Blood samples were extracted with the solid-phase extraction method and the liquid-liquid method. This method is suitable in forensic toxicology analysis for basic drugs.

Antidepressive Agents, Tricyclic↗
PubMed1997

[The hepatic ischemia/reperfusion injury in cirrhotic rats].

We assessed ischemia/reperfusion injury in carbon tetrachloride induced cirrhotic liver as compared to normal liver in the rats. Hepatic vein nitric oxide (NO) level was measured by method of luminol chemiluminensence, and portal vein endotoxin level by limulus lysate with chyomogenic substract. In cirrhotic liver, instead of diminishing the hepatic vein NO level increased significantly after ischemia and remained high till 5 hrs postreperfusion. The portal vein endotoxin level was also increased but to a higher level than that of normal liver. In cirrhotic liver, ischemia/reperfusion injury is aggrevated as evidenced by higher level of endotoxin, increased generation of NO.

Animals↗
PubMed1997

[The long-term results of surgical treatment in 103 cases of hilar cholangiocarcinoma].

We studied characteristics including clinicopathology, operation style, late survival rate of 103 patients with hilar bile duct carcinomas treated surgically in our hospital between 1986 and 1996. The factors affecting surgical treatment and late result of hilar bile duct carcinoma were analyzed. Of the 103 patients, subjected to 66 (radical resection, 36; palliative resection, 30) were section, and 37 (internal drainage, 11; external drainage, 26) were not. The total resectional rate was 64.1%. Operative mortality was 2.9% for palliltive or noresctive groups. In the radical resection group, the 1, 3 and 5-year survival rates were 96.7%, 23.3% and 13.2%, and the longest survival time was more than 8 years, whereas in the palliative resection group, the 3-year survival rate was only 3.8% and no one survived for over 5 years. In the unresected group, the survival time of the patients with internal drainage was longer than that of the patients with external drainage, but their viability was not improved significantly. Most of them died within 12 months. We proposed the new clinical types for hilar bile duct carcinoma. The pathological type in all patients survived for over 5 years was welldifferatiated papillary or tubular adenocarcinomas. The secondary operative rate in these patients was high. This showed that the biological characteristic is very important for the long-term results of bile duct carcinoma after operation.

Adenocarcinoma↗
PubMed1997

[Complications of laparoscopic cholecystectomy in China: analysis of 39,238 cases].

All Chinese articles published from November 1995 through April 1994 about laparoscopic cholecystectomy were identified through CMCC. From 600 titles, 105 were read and left for analysis. Other 21 articles were from the 6th Biliary Surgical Congress and this hospital. Severe complications of laparoscopic cholecystectomy were identified in 409 patients (0.4%), bile duct injury accounted for 0.32%, postoperative cystic duct leak and bile leak for 0.11% and 0.20% respectively. Peritoneal abscess and bowel injury occurred in 0.07% and 0.06% of cases, and postoperative hemorrhages were identified in 0.1% of the cases. Fourteen (0.04%) postoperative deaths resulted from operative injury. The data demonstrate that laparoscopic cholecystectomy is an operation which associated with low morbidity and mortality. But bile duct injury is still a problem, and complications of laparoscopic cholecystetomy can be minimized by improving operative procedure.

Bile Duct Diseases↗
PubMed1997

[Immunogenecity of expressed protein p68 from recombinant plasmid rpDJt in L. interrogans serovar lai].

There are two types of infection caused by pathogenic microorganisms, intracellular infection and intercellular infection. Infection of pathogenic leptospira is an intercellular infection. The immunological reaction of host to intercellular infection is unique. The potential immunogen of an expressed protein should meet three criteria: it can be degraded (by antigen-present cells in the host); it should have antigenic epitope which can be recognized by specific antibodies and have at least one epitope that can be recognized by an MHC II protein and T cell receptor. In this study we report the cloning of an L. interrogans protein in plasmid rpDJt and the immunogencity of the expressed protein derivative. A genomic library of L. interrogans serovar lai strain 017 was constructed with the plasmid vector pUC18. Recombinant plasmids, designated pDJH2 and pDJ8 were screened from the bank. EcoRI-inserted fragment of 1. 9 kb recombinant DNA of pDJH2 was ligated into T7 RNA polymerase/promoter vectors (pT7-7). Then they were transformed into E. coli JM109 (De3), one of subclones, designated rpDJt was achieved. SDS-PAGE showed that the molecular weights of expression proteins were 68 kd and 23 kd respectively, designated p68 and p23. Purifying and isolating p68 and p23, we separated them from SDS-Polyacrylamide gels by using Side-Strip method. After fragmenting and electroeluting, p68 and p23 were injected into guinea pigs and rabbits. An extremely strong immune response to p68 was obtained since an anti-p68 antibody response could be detected to a dilution 1:524,288 (guinea pigs) and 1:262,144 (rabbits) by ELISA while anti-P23 antibody being 1:1024 (the same to guinea pigs and rabbits). The results of improved MTT and conA 3HTdR transformation methods showed the activities and proliferation of Th-cells were increased in guinea pigs after p68 immunization (IL-6, 83.25 IU/ml, IL-2, 28.75 IU/ml; RPI, 2.04, SI, 65.62%) Thlymphocyte existed in two subclasses, the Th1- and Th2-cells. A major role of Th2-cells is to "help" B-cells differentiate, replicate, and secrete antibody. The properties of these interactions explain why p68 makes good antigen and p23 does not. The antigens responsible for eliciting the production of protective antibodies are not known; however, several outer membrane proteins on L. interrogans are candidates for vaccine. Our results suggest that expresion protein p68 from recombinants (rpDJt) may be a candidate for gene engineered subunit vaccine for Leptospirosis.

Animals↗
PubMed1997

[Construction of genomic library of L. interrogans serovar lai using lambda gt11 as the vector and a study of recombiant plasmid pDL121].

A genomic library of L. interrogans serovar lai strain 017 has been constructed using lambda gt11 as the vector. DNA was partially digested by two blunt-end restriction enzymes, then methylated with EcoR I methylase; after EcoR I linker was added to the DNA, the linker-ended DNA was ligated to the dephosphorylated EcoR I digested lambda gt11 arms. The recombined DNA was packaged in vitro, and used to transduct E. coli Y1090 for amplification. There were 2.1 x 10(6) recombinant bacteriophages as recognized by their ability to form white plaques plated on Lac host in the presence of both IPTG and X-Ga1. A positive clone, designated lambda DL12, was screened with a rabbit anti-serum against L. interrogans serovar lai from the genomic library. The DNA from lambda DL12 was subcloned into plasmid pUC18. A recombinant (designated as pDL121) was obtained. SDS-PAGE analysis indicated that a 23 kd was expressed in E. coli JM 103 harboring pDL121. Western blotting analysis showed that a specific protein band molecular weight of 23 kd could be recognized by the rabbit antiserum against L. interrogans serovar lai strain 017.

Cloning, Molecular↗
PubMed1997

[Multi-operations for non-small cell lung cancer].

OBJECTIVE: Experiences and results of multi-operations in order to raise the survival rate of advanced non-small cell lung cancer are presented. METHODS: Fifty-six operations were performed in 26 patients with recurrent, metastatic or second primary non-small cell lung cancer. The operative procedure and the postoperative complications were observed and survival was analysed with Kaplan-Meier of SPSS. RESULTS: The postoperative complication rate of the first operation was 3.8%. The 1-, 3- and 5-year survival rates were 83.5%, 58.4% and 35.7% respectively with a median survival of 46 months. The second postoperative complication rate was 26.9% and operative mortality was 11.5%. 1-, 3- and 5-year cumulative survival rates were 55.8%, 17.1% and 17.1% respectively with a median survival of 15 months. The third for 2 cases survived 18 and 17 months respectively. The forth and fifth were carried out for the same patient all in the sixth month. The fifth operation gave a survival of 8 months. CONCLUSION: Multi-operations for non-small cell lung cancer are still effective for recurrent, metastatic or second primary lung cancer. Simple spirometry is far from being satisfactory to evaluate pulmonary function for these patients. Meticulous attention must be paid to complication of respirative failure and infra-thoracic hemorrhage.

Adult↗
PubMed1997

[Debulking operation for non-small cell lung cancer].

OBJECTIVE: To assess effectiveness and influencing factors of debulking operation for non-small cell lung cancer. METHODS: The cumulative survival and its influencing factors were analyzed and compared by the Kaplan-Meier and Cox model of SPSS for Windows in 244 patients received debulking operation and 364 received thoracotomy. RESULTS: The 1, 3, 5-year cumulative survival of patients treated with debulking operation was 56.9%, 20.6%, 17.5% respectively while that received thoracotomy was 41.1%, 7.8%, 5.3%, respectively (debulking vs thoracotomy, Breslow = 27.55, P < 0.0001). Multivariate analysis showed that the debulking operation or thoracotomy (B = -0.4600, P < 0.0001) and postoperative adjuvant therapies (B = -0.1059, P = 0.0216) were the most important influencing factors on the cumulative survival. CONCLUSION: Tumor debulking operation is an important treatment for stage III, IV non-small cell lung cancer. With postoperative adjuvant chemoradiotherapy better survival can be achieved.

Adult↗
PubMed1997

[The observation on treatment effects of local adoptive immunotherapy in 33 cases with head and neck cancer].

OBJECTIVE: To evaluate treatment effects of local adoptive immunotherapy in 33 cases with head and neck cancer. METHODS: IL-2 1 x 10(5)-2 x 10(5) U per day was injected into tumor for 10 days; during the 4th-8th day LAK cells 1.0 x 10(8)-5.0 x 10(8) per day were combined with IL-2 injection. Then we analysized clinical effect, immunopathology, side effects, etc. RESULTS: CR was seen in 1 case; PR in 6, MR in 20 cases, and SD in 6 cases. The one-, two- and three-year survival rate was 96.3%, 83.3% or 75.0% respectively. The results of histopathology showed that there were large amount of T lymphocytes (CD3+/4+) infiltrating in the tumor area after immunotherapy. No serious side effects were found during the course of the treatment. CONCLUSION: Local injection of IL-2/LAK can be used as immunotherapy for head and neck cancer.

Adolescent↗
PubMed1997

[Water vapor permeability measurement of the materials used as a wound covering].

This paper introduces a new apparatus and method that suits to measuring the water vapor transmission rate (WVTR) of wound covering materials. WVTR of synthetic materials, amniotic membrane, porcine and cadaveric skin was measured under different conditions of four temperatures, three mediums, and "water cup" or "inverted water cup". The temperature was in close relationship with the WVTR except Omiderm, amniotic membrane, and cadaveric skin between 30 degrees C and 37 degrees C groups. The medium did not affect the WVTR (P > 0.05). There was significant difference between the "water cup" and "inverted water cup" groups(P < 0.01). This study suggests that the apparatus is easy-to-operate, reliable and suitable for the measurement of WVTR of burn wound coverings and other membranous materials.

Bandages↗