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Biomedical subjects

Bo Zhang

Publications and source records attributed to Bo Zhang.

At least 235 records · Page 13Linked to original sources
PubMed2003

[Diagnosis and treatment of seminal vesicle cyst].

OBJECTIVES: To deepen the understanding of patients with seminal vesicle cyst for correct diagnosis and treatment. METHODS: Sixteen patients with seminal vesicle cysts were treated in the period of January 1980-May 2002. Their symptoms, diagnostic results, treatment and outcomes were analyzed retrospectively. The mean age of these patients at diagnosis was 31 years (range 19 - 43). Two patients were associated with ipsilateral renal agenesis. Symptoms included hematospermia in 12 (75%) patients, urinary frequency in 8 (50%), hematuria after ejaculation in 6 (27.5%), perineal malaise in 6 (27.5%), infertility in 3 (13.7%), pain after ejaculation in 3 (13.7%), scrotal pain in 2 (12.5%) and dysuria in 1 (6.3%). Cyst was palpable in 81.3% patients on digital rectal examination. All patients underwent intravenous urography and cystoscopy. Others received ultrasonography, CT scanning, MRI, and vasovesiculography. The size of masses ranged from 3.8 cm x 3.0 cm x 2.6 cm to 9.6 cm x 5.2 cm x 5.0 cm. Final open surgery consisted of vesiculectomy (4 patients) and partial vesiculectomy (12). RESULTS: Postoperative course was uneventful except in 1 patient with epididymitis. All patients were free of symptoms after open surgery. CONCLUSIONS: Seminal vesicle cysts are rare but should be considered in men with hematospermia and otherwise inexplicable bladder irritation symptoms, perineal discomfort or other genitourinary complaints of unknown etiology. Diagnosis consists of digital rectal examination, transrectal and abdominal ultrasonography, CT scan or MRI. Vesiculectomy and partial vesiculectomy give excellent results.

Adult↗
PubMed2003

[Characterization of telomerase regulation association gene TRAP and cancer biology].

OBJECTIVE: To investigate expression of TRAP in human tumors and correlativity between TRAP and hTERT and to explore the role of TRAP in tumorigenesis. METHODS: TRAP was expressed in E. coli. and polyclonal antibody was prepared by immunization of New Zealand rabbits. Expressions of TRAP gene and hTERT in human tumors were analyzed by immunohistochemistry. The eukaryotic expression vectors of TRAP were constructed and transferred stably into HeLa cells to be analysed with Northern blot, TRAP-PCR ELISA, growth curve, nude mouse transplantation. RESULTS: Polyclonal antibody was obtained from New Zealand rabbits immunized with TRAP fuse protein, which was inducibly expressed in E. coli., and its specificity was verified in Western blot. TRAP staining was detected in 213 (86.2%) of 247 malignant tumors. On the contrary, TRAP in all tissues adjacent to tumors was negative. There is a obvious difference between borderline, pre-cancerous and benign lesion in the expression of TRAP. Furthermore, hTERT staining was conducted and its result was consistent with that of TRAP. Up-regulation and down-regulation of hTERT expression and telomerase activity were observed respectively in HeLa cells transfected stably with sense and antisence TRAP recombination. Increased proliferation presented in the former and growth inhibition in the latter. Besides, in nude mice, tumorigenecity of sense TRAP-transfected HeLa cells was enhanced while tumor growth of antisense TRAP-transfected HeLa cells was retarded. CONCLUSION: The expression of TRAP, which could be detected in most of human cancers and part of pre-cancerous lesions, was correlated with expression of hTERT. The status of TRAP expression could regulate telomerase activity and present effects on growth and tumorigeneity of cancer cells. This suggests that TRAP is involved in human tumorigenesis through regulation of telermarase activity.

Acid Phosphatase↗
PubMed2003

[Expression of telomerase and telomerase associated-regulation protein and proliferating cell nuclear antigen in ovarian epithelial tumors].

OBJECTIVE: To investigate expression and significance of hTERT, telomerase associated-regulation protein (TRAP) and proliferating cell nuclear antigen (PCNA) in ovarian epithelial tumors. METHODS: 106 specimens of ovarian epithelial tumors and their clinical history were collected, including 54 cases of malignancy, 33 borderline cases and 19 benign tumor cases. Immunohistochemical staining for hTERT, TRAP and PCNA were performed. Follow-up information was obtained for 45 of 87 cases (malignancy in 54 and borderline malignancy in 33). RESULTS: The expression of hTERT was significantly different between benign (4/19) and borderline (90.9%, 30/33) cases, benign and malignant (94.4%, 51/54) cases (P < 0.001), as was the expression of TRAP between benign (4/15) and malignant (77.8%, 28/36) cases (P < 0.001). The expression of hTERT and TRAP was not higher in stage III, IV ovarian cancer patients than in stage I and II (P > 0.05, P > 0.3). The expression of PCNA between benign (6.9 +/- 5.9)% and borderline (26.4 +/- 17.8)% cases, benign and malignant (51.8 +/- 22.1)% cases, and borderline and malignant cases were different, and were statistically significant (P < 0.01, P < 0.001, P < 0.05). 33 cases of borderline malignancy are all survive. In 54 cases of malignancy, 35 of them have metastasis (64.8%), including 5 cases of lymph nodes metastasis. 4 of them died (7.4%). CONCLUSIONS: The expression of hTERT and TRAP is associated with the malignant degree of ovarian cancer, but does not correlate with stage. The expression of TRAP resembles hTERT, which may be a new tumor-associated gene. Telomerase activity is positively associated with PCNA.

DNA-Binding Proteins↗
PubMed2003

[Establishment of a human CD30+ anaplastic large cell lymphoma cell line and its biological characteristics].

A CD30+ anaplastic large cell lymphoma (ALCL) cell line was established from the mononuclear cells isolated from pleural effusion of a patient with non-Hodgkin's lymphoma. The cell line's biological characteristics were analyzed. The results showed that the established cell line could survive and proliferate in RPIM 1640 medium; the Wright-Giemsa-stained cells were exactly similar to malignant cells of CD30+ ALCL in morphology, with many diffuse virus granules in cytoplasm; the cytochemical staining of the cells showed the following reactivity pattern: positive for acid phosphatase (ACP) and periodic acid-Schiff (PAS), negative for peroxidase (POX), myeloperoxidase (MPO) and platelet peroxidase (PPO). The immunoprofile of the cells was positive for CD45, HLA-DR, CD30 and negative for EMA, CD34, CD38, CD2, CD3, CD4, CD7, CD8, CD10, CD15, CD19 and CD20. The cytogenetic analysis showed complicate d qualitative and quantitative abnormality of chromosomes, without typical t(2;5). It is concluded that the established cell line is CD30+ anaplastic large cell lymphoma cell line.

Apoptosis↗
PubMed2003

[Expression of telomerase and p53 in ameloblastoma].

OBJECTIVE: To detect the expression of p53 protein, hTR, and hTERT mRNA in ameloblastoma (AB) and to investigate the clinical biological characteristics of AB. METHODS: We detected hTR and hTERT Mrna in 54 cases of AB by in situ hybridization, and p53 protein by S-P method. RESULTS: The positive ratio of hTR, hTERT mRNA was 2/7 and 1/7 in normal oral mucosa, 81.2%(13/16) and 87.4% (14/16) in odontogenic keratocyst (OKC), 94.4%(51/54) in AB, respectively. There was a significant difference in these three groups (P < 0.001). A strong correlation between hTR and hTERT mRNA was found (rs = 1.000, P < 0.001). p53 protein was expressed in 87.5% (42/49) AB, 44%(11/25) OKC, 33.3%(1/3) normal oral mucosa, respectively. A strong correlation between hTERT mRNA and p53 protein was found (rs = 0.848, P < 0.001). A moderate correlation between hTR mRNA and p53 protein was found (rs = 0.536, P < 0.001). CONCLUSION: The positive ratios of hTR and hTERT were higher than p53 protein in AB. Telomerase activity and p53 expression play an important role in genesis and development of AB.

Adolescent↗
PubMed2003

[Measurement of soluble CD44v6 in peripheral blood as assistant diagnosis of invasive pituitary adenomas].

OBJECTIVE: To investigate the value of measuring the concentration of soluble CD44 splice variant 6 (sCD44v6) in peripheral blood in patients with invasive and non-invasive pituitary adenomas. METHODS: The concentrations of sCD44v6 in peripheral blood were measured with ELISA in 68 patients with invasive pituitary adenomas and 100 patients with non-invasive pituitary adenomas. RESULTS: The serum concentration of sCD44v6 in patients with invasive pituitary adenomas was lower than that in patients with non-invasive pituitary adenomas, while the latter was lower than that in healthy controls. The serum concentrations of sCD44v6 were (44.63 +/- 7.21), (34.53 +/- 6.41), and (26.34 +/- 4.95) ng/ml in patients with invasive microadenoma, macroadenoma, and giant adenoma, and (60.78 +/- 9.61), (57.78 +/- 10.00), and (37.22 +/- 5.17) ng/ml in patients with non-invasive microadenoma, macroadenoma, and giant adenoma, lower than that in the healthy control group (68.73 +/- 6.00) ng/ml. Significant differences were observed among groups (P < 0.005). The concentration of sCD44v6 in peripheral blood decreased as the tumor size increased (P < 0.01), which was particularly significant in invasive pituitary adenomas. The positive rate in the patients with invasive pituitary adenomas reached 89.71%. CONCLUSION: Serum concentration of sCD44v6 in the peripheral blood is inversely correlated with tumor size and its invasive growth, which may provide certain value in the early diagnosis, treatment and prognosis of invasive pituitary macroadenoma and giant adenoma.

Adenoma↗
PubMed2003

[Typing for HLA-DR DNA by polymerase chain reaction with sequence-specific primers].

AIM: To type the HLA-DR DNA for renal transplantation by PCR with sequence specific primers (PCR-SSP). METHODS: According to nucleotide sequences of HLA-DR, 16 pairs of specific primers and a pair of positive control primers were designed and synthesized for PCR-SSP. Then HLA-DR sites of 52 donors and recipients for renal transplantation were typed by the PCR-SSP. RESULTS: All the samples were successfully typed by PCR-SSP with the synthesized primers. The results were available within 3 hours after sampling and the accuracy and reproducibility were 100%. CONCLUSION: Genotyping for HLA-DR sites by PCR-SSP with primers reported herein was a simple and accurate technique suitable for clinical application.

Adolescent↗
PubMed2002

Identification of a "glycine-loop"-like coiled structure in the 34 AA Pro,Gly,Met repeat domain of the biomineral-associated protein, PM27.

Fracture resistance in biomineralized structures has been linked to the presence of proteins, some of which possess sequences that are associated with elastic behavior. One such protein superfamily, the Pro,Gly-rich sea urchin intracrystalline spicule matrix proteins, form protein-protein supramolecular assemblies that modify the microstructure and fracture-resistant properties of the calcium carbonate mineral phase within embryonic sea urchin spicules and adult sea urchin spines. In this report, we detail the identification of a repetitive keratin-like "glycine-loop"- or coil-like structure within the 34-AA (AA: amino acid) N-terminal domain, (PGMG)(8)PG, of the spicule matrix protein, PM27. The identification of this repetitive structural motif was accomplished using two capped model peptides: a 9-AA sequence, GPGMGPGMG, and a 34-AA peptide representing the entire motif. Using CD, NMR spectrometry, and molecular dynamics simulated annealing/minimization simulations, we have determined that the 9-AA model peptide adopts a loop-like structure at pH 7.4. The structure of the 34-AA polypeptide resembles a coil structure consisting of repeating loop motifs that do not exhibit long-range ordering. Given that loop structures have been associated with protein elastic behavior and protein motion, it is plausible that the 34-AA Pro,Gly,Met repeat sequence motif in PM27 represents a putative elastic or mobile domain.

Amino Acid Sequence↗
PubMed2002

Super/subcritical fluid chromatography chiral separations with macrocyclic glycopeptide stationary phases.

The chiral recognition capabilities of three macrocyclic glycopeptide chiral selectors, namely teicoplanin (Chirobiotic T), its aglycone (Chirobiotic TAG) and ristocetin (Chirobiotic R), were evaluated with supercritical and subcritical fluid mobile phases. A set of 111 chiral compounds including heterocycles, analgesics (nonsteroidal antiinflamatory compounds), beta-blockers, sulfoxides, N-protected amino acids and native amino acids was separated on the three chiral stationary phases (CSPs). All separations were done with an outlet pressure regulated at 100 bar, 31 degrees C and at 4 ml/min. Various amounts of methanol ranging from 7 to 67% (v/v) were added to the carbon dioxide along with small amounts (0.1 to 0.5%, v/v) of triethylamine and/or trifluoroacetic acid. The Chirobiotic TAG CSP was the most effective closely followed by the Chirobiotic T column. Both columns were able to separate, partially or fully, 92% of the enantiomers of the compound set. The ristocetin chiral selector could partially or baseline resolve only 60% of the enantiomers tested. All separations were done in less than 15 min and 70% were done in less than 4 min. The speed of the separations is the main advantage of the use of SFC compared to normal-phase HPLC. In addition, SFC is advantageous for preparative separations with easy solute recovery and solvent disposal.

Chromatography, Liquid↗
PubMed2002

[A preliminary study on the immune suppressive protein of stress in human tonsil].

Our previous work demonstrated that under the conditions of restraint stress and under the control of central nervous system (CNS), an immune suppressive protein of stress (ISPS) was generated in peripheral lymph tissue and released into the blood stream, acting as an immune suppressor. In the present work, a protein similar to ISPS was found in human tonsil (a peripheral lymph tissue). Human tonsil was homogenized and the extract was prepared. It was found that lymphocyte proliferation was significantly suppressed by the extract. The suppression induced by the extract was partially reversed by the monoclonal antibody against ISPS (2C4). In ELISA test, the extract was able to bind to the monoclonal antibody. By immunohistochemistry, many ISPS positive cells were found in human tonsil. The ISPS positive cells were also found in human lymph nodes. Taken together, all the results demonstrate that a protein similar to ISPS may exist in human peripheral lymphoid tissue.

Animals↗
PubMed2002

Direct measurement of the laplace pressure in a very thin liquid film.

Meniscus force plays an important part in magnetic storage devices, scanning probe microscopy, and micromachines, because the meniscus force increases steeply as the clearance between solid surfaces decreases down to submicrometers. Recently increased experimental and analytical studies on the subject have been published from the point of view of mechanical engineering. Meniscus force is generated by the Laplace pressure within the thin liquid film. Investigating the Laplace pressure is a direct way to clarify the generation mechanism of meniscus force. However, no appropriate measuring method of the Laplace pressure is available for a very thin liquid film confined by solid surfaces. This paper proposes a simple method of direct measurement of the Laplace pressure for the cases. The principle of the measurement method is described. Measurement is conducted using the measuring device. Experimental results on the Laplace pressure show good agreement with the theoretical predictions.

Journal Article↗
PubMed2002

Model peptide studies of sequence regions in the elastomeric biomineralization protein, Lustrin A. I. The C-domain consensus-PG-, -NVNCT-motif.

The lustrin superfamily represents a unique group of biomineralization proteins localized between layered aragonite mineral plates (i.e., nacre layer) in mollusk shell. Recent atomic force microscopy (AFM) pulling studies have demonstrated that the lustrin-containing organic nacre layer in the abalone, Haliotis rufescens, exhibits a typical sawtooth force-extension curve with hysteretic recovery. This force extension behavior is reminiscent of reversible unfolding and refolding in elastomeric proteins such as titin and tenascin. Since secondary structure plays an important role in force-induced protein unfolding and refolding, the question is, What secondary structure(s) exist within the major domains of Lustrin A? Using a model peptide (FPGKNVNCTSGE) representing the 12-residue consensus sequence found near the N-termini of the first eight cysteine-rich domains (C-domains) within the Lustrin A protein, we employed CD, NMR spectroscopy, and simulated annealing/minimization to determine the secondary structure preferences for this sequence. At pH 7.4, we find that the 12-mer sequence adopts a loop conformation, consisting of a "bend" or "turn" involving residues G3-K4 and N7-C8-T9, with extended conformations arising at F1-G3; K4-V6; T9-S10-G11 in the sequence. Minor pH-dependent conformational effects were noted for this peptide; however, there is no evidence for a salt-bridge interaction between the K4 and E12 side chains. The presence of a loop conformation within the highly conserved -PG-, -NVNCT- sequence of C1-C8 domains may have important structural and mechanistic implications for the Lustrin A protein with regard to elastic behavior.

Amino Acid Sequence↗
PubMed2002

Suppressive effects of phosphodiesterase type IV inhibitors on rat cultured microglial cells: comparison with other types of cAMP-elevating agents.

We investigated the effects of inhibitors of cAMP-specific phosphodiesterase type IV (PDE IV) on cultured rat microglial cells. Microglial cells expressed mRNA encoding PDE IV. Rolipram and RO-20-1724, specific inhibitors of PDE IV, elevated the intracellular cAMP level much higher than the other types of PDE inhibitors. cAMP in astrocytes but not in cerebrocortical neurons was similarly increased in response to treatment with PDE IV inhibitors examined. The PDE IV inhibitors, a beta-adrenergic agonist isoproterenol and an adenylyl cyclase stimulant forskolin suppressed the proliferation of microglial cells as revealed by PCNA-immunocytochemical staining. The PDE IV inhibitors suppressed release of TNF alpha and nitric oxide (NO) from lipopolysaccharide-activated microglial cells in pure culture, while they did not affect NO release from microglial cells in neuron-microglia coculture. The PDE IV inhibitors also suppressed superoxide anion production by phorbol ester-treated microglial cells. Isoproterenol and forskolin similarly suppressed the macrophage-like functions of activated microglial cells. However, the PDE IV inhibitors displayed novel effects distinct from those of isoproterenol, forskolin and 8Br-cAMP, regarding expression of mRNAs encoding PDE IV, metallothionein-1 and hemeoxigenase-1. The present data showed that the PDE IV inhibitors can be available to control microglial function and that their effects on glial cells should be taken into account when PDE IV inhibitors are used for treatment of brain diseases, such as multiple sclerosis.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed2002

Effects of norepinephrine on rat cultured microglial cells that express alpha1, alpha2, beta1 and beta2 adrenergic receptors.

Microglial cells rapidly become activated in response to even minor damage of neurons, suggestive of the intimate interactions between neurons and microglial cells. Although mediators for microglia-neuron interactions have not been well identified, neurotransmitters are possible candidates transmitting signals from neurons to microglial cells. Among the neurotransmitters, we focused on the effects of norepinephrine and other adrenergic agonists on the functions of rat cultured microglial cells. Reverse transcriptase polymerase chain reaction studies revealed that microglial cells expressed mRNAs encoding alpha1A, alpha2A, beta1 and beta2 receptors. Norepinephrine and a beta2 adrenergic agonist terbutaline elevated intracellular cAMP level of microglial cells. Norepinephrine, an alpha1 agonist phenylephrine, a beta1 agonist dobutamine and terbutaline suppressed the expressions of mRNAs encoding pro-inflammatory cytokines, interleukin-6 and tumor necrosis factor alpha. Release of tumor necrosis factor alpha and nitric oxide was suppressed by norepinephrine, phenylephrine, dobutamine and terbutaline. An alpha2 agonist clonidine and dobutamine upregulated the expression of mRNA encoding catechol-O-methyl transferase, an important enzyme to degrade norepinephrine. Norepinephrine, dobutamine and terbutaline upregulated the expressions of mRNA encoding 3-phospshoglycerate dehydrogenase, an essential enzyme for synthesis of L-serine and glycine, which are amino acids necessary for neuronal survival. Clonidine upregulated the expression of mRNA encoding an anti-apoptotic factor Bcl-xL. These results suggest that norepinephrine participates in the regulation of brain function at least partly by modulating the functions of microglia.

Adrenergic alpha-Agonists↗
PubMed2002

Expression of parathyroid hormone (PTH)/PTH-related peptide receptor messenger ribonucleic acid in mice hair cycle.

There is increasing evidence that parathyroid hormone (PTH) and PTH-related peptide (PTHrP) are involved in normal skin cell growth, influence the proliferation and differentiation of the epidermis and hair follicle. PTHrP and PTH/PTHrP receptor show prominent cutaneous expression, may exert important paracrine and/or autocrine functions. The expression of PTH/PTHrP receptor in different stages of hair cycle is unknown. Therefore, we examined the amount of PTH/PTHrP mRNA in C57BL/6 mice skin at different stages of hair cycle by relatively quantitative reverse transcription-polymerase chain reaction (RT-PCR), and investigated the localization of this receptor in mice skin by in situ hybridization. The expression of PTH/PTHrP receptor mRNA were higher in anagen, but significantly lower in catagen and telogen. Then, the PTH/PTHrP receptor mRNA was located in the inner root sheath (IRS) in anagen and catagen, but was not detected in telogen hair follicles, although it was expressed weakly in dermis. The variety of the PTH/PTHrP receptor mRNA expression during hair cycling suggest that PTH, PTHrP and their receptors might participate in the regulation of hair cycle in mice skin.

Animals↗
PubMed2002

Micronuclei induced by sulfur dioxide inhalation in mouse bone-marrow cells in vivo.

Induction effects of sulfur dioxide (SO2) inhalation on micronuclei (MN) formation in the polychromatic erythrocytes (PCE) of mouse bone marrow were studied in vivo. It was shown that SO2 inhalation caused an increase of MN frequencies in the PCE cells in a dose-dependent manner. These results from male and female mice were very similar; no sex difference was observed. These results imply that SO2 is a clastogenic and genotoxic agent.

Air Pollutants↗
PubMed2002

1-Butanol removal from a contaminated airstream under continuous and diurnal loading conditions.

A polysulfone microporous membrane module was investigated for control of 1-butanol-contaminated gas streams. A diurnal loading condition, using two different butanol concentrations, was used to simulate start-up and stop conditions associated with shift work. The membrane module was also used to remove 1-butanol from air under continuous loading conditions in a bioreactor. The reactors were seeded with a mixed bacterial consortium capable of butanol biodegradation. Biokinetic parameters for butanol utilization were determined for the culture to be a maximum specific utilization rate (k) equal to 4.3 d(-1) and a half saturation constant (Ks) equal to 8.9 mg L(-1). A biofilter running only with diurnal loading conditions giving a "40-hr work-week" had an average 1-butanol removal rate of 29% (111 ppm, 74 gm(-3) hr(-1)) from a 350-ppm influent at the end of an 8-hr operational day. End-of-day removal varied between 4 and 67% during the operational period. With continuous steady-state operation followed by placement on a diurnal loading schedule and influent butanol concentrations increased to 700 ppm, butanol removal averaged 38% (269 ppm, 145 gm-3 hr(-1)). Under continuous loading, steady-state conditions, 1-butanol removal from the airstream was greater than 99% (200 ppm, 73 gm-3 hr(-1)). These results suggest that the bioreactor can be operated on a diurnal schedule or 40-hr week operational schedule without any decline in performance.

1-Butanol↗