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Hua Huang

Publications and source records attributed to Hua Huang.

At least 37 records · Page 2Linked to original sources
PubMed2005

[FTIR spectra-principal component analysis of phenetic relationships of Huperzia serrata and its closely related species].

Huperzia serrata is an important medicinal plant. This species is rich in inner-specific variation with various closely related species, and their individuals are also small with few identification characters. In the present paper, the method of Fourier transform infrared spectrometer with an OMNI collector was applied to obtaining the infrared spectra of 16 leaf samples including Huperzia serrata and its five closely related species (Huperzia sutchueniana, Phlegmariurus mingchegensis, Lycopodium japonicum, Selaginella doederleinii, Selaginella heterostachys). Based on the indices of wave number-absorbance, the differences of the 16 infrared spectra were compared by the method of Principal Component Analysis (PCA). The results showed that there is good correspondence between the position relationship of PCA three-dimensional plot of the samples based on the indices of wave number-absorbance of FTIR spectra and their phenetic relationship. Therefore, the infrared spectra could be applied to identifying the samples of Huperzia serrata and its closely related species.

Huperzia↗
PubMed2005

[Coupling between adherent leukocytes and blood flow].

A theoretical model was developed to simulate the coupling between the adhered leukocyte and blood flow. Methods of computational fluid dynamics (CFD) were introduced to analyze the distributions of the shear stress and the pressure on the cell surface. Meanwhile, the hemodynamical parameters were measured with laser Doppler velocimetry. The results showed that the deformation index of the leukocyte was increased with initial contact angle and Reynolds number. The blood flow induced the redistributions of the shear stress and pressure on the surface of the cell, but the maximum shear stress was on the top point of the cell. It suggests that the non-uniform distribution of shear stress on the cell surface may play a particular role in the change of cell shape and functions.

Blood Circulation↗
PubMed2005

[A kind of method for time-frequency analysis of electrocardiosignal imitation].

Electrocardiosignal (ECG) is an important evidence base for the diagnoses of cardiovascular diseases as well as for the researches in basic and clinical medicine. Because it presents typical non-steady signals, the wave in time can not reflect the essential characteristic very well. In this article, by analysis in time-frequency domain, we have obtained some typical time-frequency diagrams of normal ECG and abnormal ECG, which reflect the comparatively essential characteristics of the original signal in some aspects and seem likely to become a basis for validating the relevant diagnosis.

Algorithms↗
PubMed2004

SHP-1 regulates STAT6 phosphorylation and IL-4-mediated function in a cell type-specific manner.

SHP-1 has been shown to play positive and negative regulatory roles in IL-4-induced STAT6 phosphorylation and in IL-4-mediated functions. To determine whether SHP-1 can regulate STAT6 phosphorylation and IL-4-mediated functions in a cell type-specific manner in the immune system, we examined the IL-4 receptor (IL-4R) expression, STAT6 phosphorylation, and IL-4-mediated functions in CD4+ and CD8+ T cells of viable motheaten (me(v)/me(v)) and littermate control (+/-) mice. CD4+ T cells as well as CD8+ T cells from the lymph node of me(v)/me(v) and +/- mice expressed comparable levels of IL-4R. In CD4+ T cells, the loss of SHP-1 activity did not affect IL-4-induced STAT6 phosphorylation or IL-4-mediated function. In contrast, SHP-1-deficient CD8+ T cells from me(v)/me(v) mice failed to develop into IL-4-producing type-2 cytotoxic T cells (Tc2) in the presence of IL-4 despite that they showed comparable levels of STAT6 phosphorylation to that of +/- CD8+ T cells. Loss of SHP-1 activity also abolished IL-4-mediated inhibition of c-kit expression in bone marrow-derived mast cell (BMMC). Thus, our data suggest that SHP-1 may regulate IL-4-induced STAT6 phosphorylation and IL-4-mediated functions in a cell type-specific manner.

Animals↗
PubMed2004

Cutting edge: IL-5 primes Th2 cytokine-producing capacity in eosinophils through a STAT5-dependent mechanism.

Both type-2 CD4(+) Th cells (CD4(+)Th2) and type-2 innate effector cells play critical roles in generating type-2 immunity that can either be protective against parasitic infection or cause tissue damage in allergy and asthma. How innate effector cells acquire the capacity to produce Th2 cytokines is not entirely known. We previously showed that IL-4 induced differentiation of Th2 cytokine-producing eosinophils. To determine whether other Th2 cytokines can also induce Th2 cytokine-producing capacity in innate effector cells, we cultured bone marrow progenitor cells in the presence of various Th2 cytokines. IL-5, but not IL-13 or IL-25, primed bone marrow progenitor cells to differentiate into robust IL-4-producing cells. The majority of IL-4-producing cells induced by IL-5 were eosinophils. Importantly, IL-5 completely depended on STAT5 to promote IL-4-producing capacity in eosinophils. Thus, our study demonstrates that IL-5 functions as a potent factor that drives bone marrow progenitor cells into IL-4-producing eosinophils.

Animals↗
PubMed2004

IL-4 induces differentiation and expansion of Th2 cytokine-producing eosinophils.

Innate effector cells that produce Th2-type cytokines are critical in Th2 cell-mediated immune responses. However, it is not known how these cells acquire the ability to produce Th2 cytokines. IL-4 is a potent inducer that directs differentiation of naive CD4(+) T cells into CD4(+) Th2 effector cells. To determine whether IL-4 can induce differentiation and expansion of Th2 cytokine-producing innate cells, we used mice whose il-4 gene was replaced by a knock-in green fluorescence protein (gfp) gene. We found that, directly ex vivo, IL-4 increased the number of GFP(+) cells in the airway and the lung tissue in an Ag-specific manner. The majority of GFP(+) cells were eosinophils, suggesting that IL-4 plays a pivotal role in expanding IL-4-producing eosinophils in vivo. IL-4-producing eosinophils showed some unique features compared with IL-4-producing CD4(+) T cells. They exhibited biallelic expression of the il-4 gene when stimulated and were more dominant IL-4- and IL-5-producing cells. Furthermore, we show that IL-4 drove bone marrow progenitor cells to differentiate into Th2 cytokine-producing eosinophils in vitro. These results strongly suggest IL-4 is a potent factor in directing bone marrow progenitor cells to differentiate into Th2 cytokine-producing eosinophils.

Alleles↗
PubMed2004

[Effects of 17 beta-estradiol on the gene expression of shear stressed endothelial cells].

OBJECTIVE: To determine the protective effect of 17 beta-estradiol on endothelial cells under shear stress. METHODS: cDNA microarray technology was adopted in the analysis of gene expression of cultured human umbilical vein endothelial cells (HUVECs) that had been incubated by 17 beta-estradiol for 48 h and then exposed to low fluid shear stress (4.20 dyne/cm2) for 2 h, Normal static cultured HUVECs were selected as control. Total RNA from normal static cultured HUVECs was labeled by Cy3-dCTP, and the total RNA of HUVECs incubated by 17 beta-estradiol (10(-7) mol/L) and then exposed to low shear stress was labeled by Cy5-dCTP. The expression ratios reported are the average from the two separate experiments. RESULTS: A total of 384 genes (approximately 0.094%) exhibited differential expression. 226 genes were up-regulated and 158 genes were down-regulated. The transcription protein of up-regulated genes related to synthesis of PGI2, macrophage phagocytosis, and so on. The transcription protein of down-regulated genes related to degradation of fibrinogen, and to production of protooncogene. CONCLUSION: Estrin at the physiological concentration could protect impaired endothelial cells. Its protective effect may be related with some genes.

Cells, Cultured↗
PubMed2004

[Analysis of the difference in NIH3T3 cell protein expression profiles before and after TPA treatment using two-dimensional polyacrylamide gel electrophoresis and image analysis software].

OBJECTIVE: To establish and optimize two-dimensional (2-D) polyacrylamide gel electrophoresis (PAGE) for comparative analysis of the protein expression profiles in mouse fibroblast NIH3T3 cells before and after 12-O-tetradecanoy- lphorbol-13-acetate (TPA) treatment using image analysis software, so as to prepare for more intensive study in the identification of the proteins that mediate the biological effect of TPA. METHODS: The total cellular protein extracted from NIH3T3 cells with or without TPA treatment underwent 2-D PAGE and silver nitrate staining prior to the analysis of the differential protein expressions using image analysis software. RESULTS: Image analysis revealed obvious differential protein expressions of the cells in response to TPA treatment. CONCLUSION: High-quality instruments for 2-D PAGE, skilled electrophoretic operation and efficient image processing are all essential in the reliable identification of stable functional proteins.

Animals↗
PubMed2004

[DNA microarray reveals changes in gene expression of endothelial cells under shear stress].

cDNA microarray technology is used as a powerful tool for rapid, comprehensive, and quantitative analysis of gene profiles of cultured human umbilical vein endothelial cells(HUVECs) in the normal static group and the shear stressed (4.20 dyne/cm2, 2 h) group. The total RNA from normal static cultured HUVECs was labeled by Cy3-dCTP, and total RNA of HUVECs from the paired shear stressed experiment was labeled by Cy5-dCTP. The expression ratios reported are the average from the two separate experiments. After bioinformatics analysis, we identified a total of 108 genes (approximately 0.026%) revealing differential expression. Of these 53 genes expressions were up-regulated, the most enhanced ones being human homolog of yeast IPP isomerase, human low density lipoprotein receptor gene, Squalene epoxidase gene, 7-dehydrocholesterol reductase, and 55 were down-regulated, the most decreased ones being heat shock 70 kD protein 1, TCB gene encoding cytosolic thyroid hormone-binding protein in HUVECs exposed to low shear stress. These results indicate that the cDNA microarray technique is effective in screening the differentially expressed genes in endothelial cells induced by various experimental conditions and the data may serve as stimuli to further researches.

Cell Division↗
PubMed2004

[Clinical analysis of 58 cases intraoperative image-guidance in nasal endoscopic surgery].

OBJECTIVE: To evaluate the availability and our experience of intraoperative image-guidance in endoscopic nasal surgery. METHODS: Fifty-eight cases of endoscopic nasal surgery with intraoperative image-guidance were retrospectively reviewed, including 39 cases of chronic sinusitis with or without nasal polyp; 3 cases of necrotizing maxillary sinusitis; 6 cases of sphenoid sinus cyst; 2 cases of nasopharyngeal angiofibroma; 1 case of cranio-nasal meningioma; 1 case of traumatic cerebrospinal rhinorrhea; 1 case of traumatic optic nerve lesion. All patients were operated on with Brain Lab operation imaging navigation system and nasal endoscope. RESULTS: The preoperative preparatory time would take 10-20 minutes, including coordination, head holder localization, conventional instrument registration. In our cases, the localization accuracy between 3-D image landmarks of navigation system and actual anatomical landmarks was less than 1.5 mm. The optic nerve and other anatomical points could be orientated accurately in intraoperative procedures. No complication occurred. CONCLUSIONS: Nasal endoscope combined with image-guidance systems provides accurate anatomical localization of nasal cavity, sinuses and anterior skull base with enlarged operation field. It is possible for surgeons to observe the surrounding important anatomical structures during endoscopic nasal surgery. It could increase the effectiveness and decrease surgical complications, especially in complicated cases.

Adolescent↗
PubMed2004

[A system for testing alternating frequency properties of body fluid and tissues].

The electric properties of biotic tissues are of importance to our understanding biotic substances even life. But the measurement taken in this aspect is different from the measurement of ordinary materials, we need a special testing instrument for living substances. In order to understand the alternating frequency properties of body fluid and tissues in detail, we have developed an electricity characteristic testing system, which is more proper for testing living substances. This system adopts advanced measuring method and expert circuit. As the measure and the control core, the single chip processor is used. This system has wide frequency range and wide impedance testing range, much more adapted objects, and it is dependable, more precise and intelligent. The application of this system in practical testing has obtained optimal results.

Body Composition↗
PubMed2003

[Establishment of transgenic mouse models carrying human polymeric immunoglobulin receptor gene].

OBJECTIVE: To establish transgenic mouse models carrying human polymeric immunoglobulin receptor (pIgR) gene to render the mice prone to EBV infection in normal condition, thereby to facilitate the study of the role of Epstein-Barr virus (EBV) in the pathogenesis of nasopharyngeal carcinoma. METHOD: By means of microinjection, pIgR gene under the regulation by kerotinocyte-specific promoter ED-L2 was introduced into the pronuclei of mouse zygote, which was transferred into pseudo- pregnant female mice to induce nasopharynx-specific pIgR expression in the founder mice. RESULT: Six out of the 16 founder mice (37.5%) was tested by PCR to be pIgR-positive, while Southern blotting identified only 2 positive mice. CONCLUSION: Transgenic mice harboring pIgR gene can be used potentially as a new model for studying the pothogenesis of nasopharyngeal carcinoma by EBV.

Animals↗
PubMed2003

[A biomechanical model for simulating the deformation of a leukocyte adhered to the surface of a blood vessel under steady shear flow].

The adhesion of leukocytes to substrate is an important biomedical engineering problem and has drawn extensive research. In this study, we have proposed a compound drop model to simulate a leukocyte with a nucleus adhered to the surface of a blood vessel under steady shear flow. A two-dimensional computational fluid dynamics (CFD) is conducted to determine the local distribution of pressure on the surface of the adherent model cell. By introducing the parameter of deformation index (DI), we have investigated the deformation of the model cell and it's nucleus under controlled conditions. Our numerical results show that: (1) the model cell is capable of deformation with the increase of initial contact angle, capillary number, and Reynolds number, and that the cytoplasm is more deformable while the nucleus is more capable of resisting external imposed shear flow; (2) the model cell is not able to deform infinitely with the increase of external shear flow because the deformation index reaches a maximum; (3) pressure distribution confirms that there exists a region downstream of the cell, which produces high pressure to retard continuous deformation and provide a positive lift force on the cell. Our results of nucleus deformation may help to develop a better understanding of how leukocytes transduce external mechanical signal like shear stress into nucleus.

Biomechanical Phenomena↗
PubMed2003

[A system applying cyclic biaxial mechanical strain to cultured cells].

To study the response of cultured cells to the cyclical biaxial biomechanical strain, a system was made according to the principle of Winston. The system was made of culture dish, pressure cavity and step motor. The culture dishes were made of polymethyl methacrylate and the bottom of the culture dishes were made of silicone rubber membrane. When the diameter of the silicone rubber tube and the distance between rollers and curvilinear plate changed, the pressure in the pressure cavity changed and the strain of the membrane changed from 0 to 4%. When the roll of the step motor changed, the frequency of the strain changed from 0.1 to 5 Hz.

Animals↗
PubMed2003

[Effects of yixintong on regulating cellular calcium channels].

OBJECTIVE: To explore the protecting mechanism of Yixintong for heart ischemia-reperfusion injury at cellular and subcellular levels, by observing the effects of Yixintong on three kinds of calcium channels. METHOD: The effects of Yixintong on Ca2+ influx on leak calcium channel, receptor-operationg calcium channel (ROC) and pulse-dependent calcium channel (PDC) were observed respectively, by using rat aortic smooth muscle cell and radioactive 45Ca technique. RESULT: Yixintong has no effects on leak calcium channel, but can inhibit the Ca2+ influx in ROC and PDC significantly. CONCLUSION: Yixintong can inhibit the Ca2+ influx in slow channel in a dose-dependent manner.

Animals↗
PubMed2002

Repression of transcription and interference with DNA binding of TATA-binding protein by C-terminal alternatively spliced p53.

The protein encoded by C-terminal alternatively spliced p53 mRNA (p53as) has been shown previously to occur naturally in mouse cells and to bind sequence-specifically to DNA more efficiently than p53 (p53r, regular form). In the current study, p53as and p53r proteins ectopically expressed in p53-deficient cells each transactivated reporter plasmids containing p53 binding sites. However, p53as consistently was more efficient in transcriptional repression of promoters lacking p53 binding sites and in concentration-dependent repression of the p21(WAF1/Cip-l/Sdi) promoter sequence. The p53as protein, like p53r, associated with TATA-binding protein (TBP), indicating that this interaction does not require the last 26 amino acids of p53. Consistent with its stronger repression effects, p53as interfered with TBP binding to a TATA-containing DNA sequence more efficiently than p53r protein. Taken together, these in vitro and in vivo results demonstrate a novel role in transcriptional repression for a naturally occurring C-terminal variant form of mouse p53 protein associated with differences in DNA binding properties and interference with transcription factor binding.

Alternative Splicing↗
PubMed2002

Rapid isolation of cancer cells from tumor tissue by micromanuiplator and extraction of tiny amount of RNA.

OBJECTIVE: To establish a rapid method for isolating and purifying cancer cells from tumor tissue and for RNA extraction from tiny amount of the cells thus obtained. METHODS: Frozen sections of the tumor tissues were prepared followed by rapid staining. Clusters of the cancer cells were isolated from the sections by micromanipulation technique and purified for extracting intact RNA that was subsequently assayed. RESULTS: Clear vision was achieved by the staining of the sections. The cancer cell clusters were precisely isolated from which high-quality intact RNA was obtained as demonstrated by reverse transcriptase-PCR. CONCLUSION: Micromanuiplation can be effectively used in stead of laser capture microdissection to isolate and purify targeted cells from tiny amount of tissue samples, therefore making RNA extraction possible in this context.

Electrophoresis, Agar Gel↗