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PubMed1995

Biological characteristics of the globular substance in the otoconial membrane of the guinea pig.

Biological characteristics of the globular substance, which is considered to be a precursor of otoconia, were investigated by means of confocal laser scanning microscopy. The shape of the globular substance was a complete sphere, 3-10 microns in diameter. Its surface stained positively with both rhodamine 123 and DiOC6(3), implying similarity to intracellular organelles, whereas no fluorescence was seen when stained with chlortetracycline, a membrane-associated Ca2+ dye. Meanwhile, this substance showed very little affinity for six kinds of lectins, indicating the lack of a surface structure of carbohydrates. The fluorescence of fluo-3 in the globular substance increased markedly after the application of ionomycin. But this was completely inhibited by the depletion of external Ca2+. This reaction suggests that the surface of the globular substance exhibits characteristics of a biological membrane and that the influx of external Ca2+ occurs through membrane-combined ionomycin. Internal free Ca2+ concentration varied from 1.1 x 10(-9) to 1.6 x 10(-4) M, the geometric mean being 3.3 x 10(-7) M, which is higher than normal resting level of intracellular Ca2+ concentration but lower than the calcium content of the globular substance estimated by X-ray microanalysis in previous studies.

Animals↗
PubMed2006

[The biological characteristics of dermal fibroblasts of the diabetic rats with deep-partial thickness scald].

OBJECTIVE: To investigate the biological characteristics of dermal fibroblasts of the diabetic rats with deep partial thickness scald, and to explore its relationship with delayed wound healing due to diabetes. METHODS: Sprague-Dawley rats weighing 250 g were randomly divided into control (NM, n=40) and STZ-induced diabetic (DM, n=50) groups, and then deep partial thickness scald involving 10% TBSA were reproduced in the two groups. Skin samples were harvested from the wounds on 0, 3, 7, 14 and 21 post scald day (PSD) for the determination of certain histological characteristics. RESULTS: The thickness of dermis layer in DM group before injury was obviously thinner than that in NM group (P < 0.01). There was an infiltration of a large amount of chronic inflammatory cells and increased content of cutaneous glucose in the dermal tissue in DM group (2.77 mg/g) compared with 0.85 mg/g in NM group, (P < 0.01). An accumulation of advanced glycation end products (AGEs) was found in the dermal tissue in DM group. After the scalding, the percentage of fibroblasts in S phase and hydroxyproline synthesis in DM group was evidently lower than those in NM group. But the apoptosis rate of fibroblasts was much higher in DM group than that in NM group (P < 0.05 or 0.01). CONCLUSION: It is found that the high contents of glucose and AGEs in diabetic skin exert untoward effects on biological characteristics of dermal fibroblast, probably constituting one of the underlying mechanisms of delay wound healing of scald in diabetic rats.

Animals↗
PubMed2005

[In vitro biological characteristics of mesenchymal stem cells from patients with myelodysplastic syndrome and their support to hematopoiesis].

To study the biological characteristics of mesenchymal stem cells (MSC) from patients with myelodysplastic syndrome (MDS) and their supportive capacity for hematopoiesis in vitro, MSCs from bone marrow samples of MDS patients were isolated, cultured and expanded. Morphology, immunophenotype, osteoblasts differentiative and proliferative property of MSC and colony forming unit-fibroblast (CFU-F) were measured and analyzed. Mononuclear cells (MNC) of cord blood were plated onto a feeder layer formed by MSC of MDS patient, cells count and CFU-GM production were observed. The results showed that the culture-expanded cells from MDS patients presented a typical fibroblast-like morphology. Cells were positive for SH2 (CD105), SH3 (CD73), Thy-1 (CD90), but negative for CD34 and CD45. After induction, these cells could differentiate into osteoblasts. Their proliferative capacity and CFU-F number were similar to those of MSC from healthy donors. The total cell count and CFU-GM yield in supernatants after culture for 2 weeks were significantly lower than those of control in hematopoiesis supportive experiments in vitro (P < 0.05). It is concluded that the biological characteristics of MSC from bone marrow of MDS patients are not different from those of MSC isolated from bone marrow of normal donors, however, their capacity of hematopoiesis support in vitro are significantly weaker.

5'-Nucleotidase↗
PubMed2005

[Culture of human epidermal stem cells in different media and their biological characteristics].

OBJECTIVE: To select the appropriate media to culture the epidermal stem cells in vitro, and to observe the biological characteristics of the epidermal stem cells. METHODS: The epidermal stem cells were cultured in five different media, including FAD, FAD+1 ng/ml bFGF, FAD+5 ng/ml bFGF, FAD+10 ng/ml bFGF and K-SFM, and the same fetus fibroblasts were used as the nutrient cells. The proliferation ability was investigated by cell growth curve and MTT detection. Then the biological characteristics of epidermal stem cells were observed through phase-contrast microscope, cell growth curve, BrdU detection and FBM analysis. RESULTS: The epidermal stem cells grew best in FAD with bFGF and nutrient cells. And the epidermal stem cells retained proliferative capacity, and formed larger and more expandable clones in vitro. And 80.2% of the cells show a G0/G1 cycle, and the cells had long cell proliferation cycle. CONCLUSION: The above results demonstrate that the media with bFGF and the use of nutrient layer were appropriate to culture epidermal stem cell in vitro. And the epidermal stem cells have a slow cell cycle, characteristics of immaturity.

Cell Adhesion↗
PubMed1991

[Biological characteristics of cultured papilla cells--localization of androgen receptors and chemotactic factor(s) for epithelial cells].

We have reported that cultured papilla cells (PCs) grown by isolation and cultivation of human hair papillae show some biological characteristics. In the present report, some important biological characteristics of PCs are showed. 1) localization of androgen receptors on PCs Localization of androgen binding protein in PCs was examined. Cytochemical staining of PCs using DHT-peroxidase conjugate gave positive reactions in the niclei of PCs originating from scalp and axilla-dermal papillae. These results suggest that androgen receptors exist in PCs. 2) chemotactic factor (s) for keratinocytes It has been demonstrated in animal experiments by Oliver, et al. that the hair papillae have an induction effect on the hair follicles. The mechanism is unknown, but PCs potentially produce and secrete chemotactic factor (s) for keratinocytes. Chemotactic response of epithelial cells to chemoattractants derived from papilla cells was examined using Bayden chamber assay. These results suggest that PCs have keratinocyte-chemotactic factors.

Androgen-Binding Protein↗
PubMed1964

PRODUCTION AND BIOLOGICAL CHARACTERISTICS OF AN EXTRACELLULAR NEUROTOXIN FROM MYCOPLASMA NEUROLYTICUM.

Tully, Joseph G. (National Institute of Allergy and Infectious Diseases, Bethesda, Md.). Production and biological characteristics of an extracellular neurotoxin from Mycoplasma neurolyticum. J. Bacteriol. 88:381-388. 1964.-Toxigenic strains of Mycoplasma neurolyticum were found to produce a potent extracellular neurotoxin for mice under a variety of cultural conditions. The observed biological characteristics of this toxin were quite similar to those originally described by Sabin. The toxin was again found to be readily inactivated by prolonged incubation and, when separated from Mycoplasma cells by filtration, possessed a greater heat resistance than whole cells. Young mice and rats were generally susceptible to neurotoxin, whereas most other experimental animals were resistant. Filtration results confirmed a minimal reproductive unit of 125 to 200 mmu for two neurotoxic Mycoplasma strains, with both cell-free filtrates reproducing the rolling disease syndrome in mice. Twice-washed Mycoplasma cells were also observed to be as neurotoxic as filtrates. Plate counting results revealed an intravenous ld(50) of approximately 3 x 10(8) washed cells for young mice.

Animals↗
PubMed2004

[Biological characteristics of HIV-1 isolates circulating in China are linked to its env V3 loop sequence variability].

OBJECTIVE: To investigate the biological characteristics of the HIV-1 isolates circulating in China and to define the association of these properties with env V3 loop sequence variability. METHODS: Primary viruses were isolated from fresh peripheral blood mononuclear cells (PBMCs) using the traditional co-culture method and their capacity of inducing syncytium was tested in MT-2 cells; meanwhile, their coreceptor usage was determined with GHOST-cell lines which stably express CD4 and the chemokine receptor CCR5 or CXCR4. Furthermore, HIV-1 V3 and its flanking region sequences were amplified by nest-polymerase chain reaction (nest-PCR) and sequenced. A GCG software was used to translate the DNA sequences into polypeptide sequences. RESULTS: Five primary viral strains were isolated from 3 different regions in China. The isolates LTG0213 and LTG0214 induced syncytia in MT-2 cells and used CXCR4 as coreceptor. The isolates XJN0021, XJN0091, and SHXDC0041 did not induce syncytia and used CCR5 as coreceptor. There were obvious differences between X4/SI and R5/NSI viruses in env V3 loop sequences. A consensus motif at the positions 8, 11, 18, and 25 in V3 loop was identified as follows: a sequence as "8-TXXS/GXXXXXXR/QXXXXXXE/D-25" will predict the usage of CCR5 coreceptor; a sequence replacing these positions with basic amino acids (except position 25) will very likely predict the usage of CXCR4 coreceptor. CONCLUSION: The biological characteristics of HIV isolates are linked to env V3 loop sequence variability: introducing basic amino acids (or translating from acidic amino acids into neutral amino acids) at the positions 8, 11, 18, and 25 in V3 loop will change viral strain's biological phenotype from NSI/CCR5 to SI/CXCR4. The biological phenotype of HIV-1 can be predicted with V3 loop sequence analysis.

China↗
PubMed2002

[Establishment and biological characteristics of human multiple myeloma cell line CZ-1].

OBJECTIVE: To establish a multiple myeloma (MM) cell line and analyze its biological characteristics. METHODS: Mononuclear cells isolated from the peripheral blood (PB) and bone marrow (BM) of an advanced MM patient (lambda light chain type) were incubated by liquid cell culture, cell morphology was analyzed by Wright-Giemsa-staining and cytochemical staining, immunophenotyping by flow cytometry, cytogenetic analysis by chromosome RHG-banding method. Quantitative fluorescent polymerase chain reaction was used to detect EBV DNA. RESULTS: The established cell line could survive and proliferate in the presence of feeder cells or conditioned medium. The cells secreted lambda light chain and were negative for EBV. The Wright-Giemsa-staining showed typical plasmablast or plasma cell morphology. The cytochemical staining of the cells showed the following reactivity pattern: positive for acid phosphatase, negative for myeloperoxidase. The immunoprofile of the cells was concordant with that of MM cells: positive for CD(10), CD(28), CD(38), CD(138), CD(56), CD(49d), CD(44), CD(54) and CD(58), negative for CD(19), CD(40), CD(95), CD(95)L, CD(34), CD(2) and CD(5). The cytogenetic analysis showed complex chromosome abnormality of i (1q +), 8q +, 13q +, i (17q), i (18q) and + M. There was no difference in morphology, immunophenotype and cytogenetics between cells from PB and BM. CONCLUSION: A MM cell line secreting lambda light chain named CZ-1, was established. The cells from both PB and BM have the same biological characteristics.

Antigens, CD↗
PubMed1984

Biological characteristics of Salmonella weltevreden typing phages.

The important biological characteristics of Salmonella weltevreden (3, 10 : r :Z6) typing phages were studied. On the basis of these, the phages could be classified into three groups: phages phi I and phi II, phages phi III, phi IV and phi VI, and phage phi V.

Antigens, Viral↗
PubMed1998

In vivo karyotypic evolution with altered biological characteristics in a case of neuroblastoma.

Molecular and biological analyses of a neuroblastoma case in which the original tumor contained a nodular region are described. No significant difference was observed between the nodular and the surrounding tumor tissue with respect to histopathologic examination, N-myc amplification, and trkA expression. However, flow cytometric analysis demonstrated that the nodular region consisted of a hypertetraploid clone, whereas the surrounding tissue mostly contained a hyperdiploid clone. Chromosome analysis showed that each clone had a similar chromosome acquisition pattern, suggesting that the hypertetraploid cells of the nodular region arose from the hyperdiploid cells of the surrounding tissue. Moreover, primary culture findings of the tumor cells showed that the responses to nerve growth factor or retinoic acid were different between the two. Collectively, this case suggests the possibility that neuroblastoma acquires novel biological characteristics through karyotypic evolution in vivo.

Abdominal Neoplasms↗
PubMed1992

Co-existence of colonies with different serotypes and other biological characteristics in clinical isolates of Pseudomonas aeruginosa.

The biological characteristics of individual colonies of Pseudomonas aeruginosa from 138 specimens were investigated. Of these isolates, 90 (65.2%) formed colonies of similar appearance and morphology, and 48 (34.8%) formed colonies which differed either in appearance or morphology. The individual colonies of 138 isolates were tested for serotype. The former 90 isolates formed only the colonies with one kind of serotype, whereas 17 of the latter 48 isolates formed the colonies with more than one kind of serotype. All the 9 isolates tested also differed in other biochemical characteristics: acid productions from xylose, mannitol and maltose, urease production and gelatin liquefaction. beta-Lactamase activity was investigated in 7 isolates forming colonies with more than one serotype. There were no marked differences in beta-lactamase activity among the different colonies in 5 isolates but marked differences among those in the other 2 isolates.

Gelatin↗
PubMed2001

[Effect of graphite and phosphate investments on the biological characteristics of pure titanium castings].

OBJECTIVE: To investigate the effect of surface structural changes caused by graphite and phosphate investments on the biological characteristics of pure titanium castings. METHODS: Round casting pads of pure titanium were processed by graphite and phosphate investments respectively, then grouped into four. With the control of guta purca of the same size, Ultraviolet spectrometry was used to test the cytotoxicity of samples via the ISO, GB and Shanghai biomaterial research and testing center's standards. Mucous irritation test was performed on hamsters' pouch. RESULT: Titanium castings obtained from both investment materials have reached the national standard of cytotoxicity and mucous irritation test no matter they have been undergone surface treatment or not. CONCLUSION: Both investment materials cause no obvious changes on biological characteristics of pure titanium castings with the existing of surface structural changes.

English Abstract↗
PubMedDate not supplied

[Biological characteristics and ecological factors determining mammalian radioresistance in the Rodentia order].

Both the results of our investigations and published data on mammalian radioresistance, biological characteristics and ecological factors which modify it are generalized in this paper. The described diversity among large taxa in radioresistance is based on the data obtained on the rodents from the Old and the New Worlds (totally 51 samples from 22 genera of four families--Sciurudae, Muridae, Cricetidae, Heteromyidae). It was found that radioresistance substantially depended on which family the species belonged. The main biological characteristics and ecological factors (body size, nutrition type, biotopical restriction) were revealed; in sum they determined 40% of radioresistance of small mammals.

Animals↗
PubMed2004

[Biological characteristics of female rabbit clitoral smooth muscle cell culture in vitro].

OBJECTIVE: To investigate the method of culturing rabbit clitoral smooth muscle cells(SMC) in vitro and their biological characteristics. METHODS: Rabbit clitoral SMCs were cultured in vitro by enzymatically dispersed method, and morphological observation, cell counting and immunohistochemical staining were employed to study their biological characteristics. RESULTS: Rabbit clitoral SMCs were spindle-shaped and parallelled along their longitudinal axis, and the attachment and proliferation in vitro were rapid. CONCLUSION: Rabbit clitoral SMCs cultured in vitro can grow and maintain their steady characteristics when provided with appropriate culture condition. Clitoral SMCs cultured in vitro can serve as a cell material for researches of clitoris.

Animals↗
PubMed2005

[Isolation and culture of mouse marrow mesenchymal stem cells (MSCs) and biological characteristics of MSCs cultured in conditions for spermatogonia in vitro].

OBJECTIVE: To isolate, culture and purify mouse bone marrow mesenchymal stem cells (MSCs) and observe the main biological characteristics of MSCs cultured in conditions for spermatogonia in vitro. METHODS: The tibias and femurs were dissected from 5 - 6-week old mice and the marrow in the tibias and femurs was flushed out with medium. MSCs were isolated, cultured, purified in vitro by Percoll density gradient centrifugation combined with adherent method and identified by dynamic observation of stem cell characteristics by transmission electron microscope, HE staining, and immunohistochemical detection of cell markers. The quantities of such cytokines as IL-6, IL-8, G-CSF and SCF in culture liquid with MSCs were measured by ELISA, and compared with those of the control group. MSCs of the third generation were divided into two groups to be induced and cultured. MSCs of the control group were cultured with basal medium, while those of the experimental group with conditional medium. The results were analysed by microscopic observation, HE staining and immunohistochemical methods. RESULTS: Pure MSCs were obtained. The cultured cells, with stem cell characteristics, shuttle-shaped at HE staining, immature under the transmission electron microscope and CD44 and CD90 positive by immunohistochemical detection, could be identified as MSCs. Compared with the control group, the quantities of IL-6, IL-8, G-CSF and SCF in the experimental group increased significantly (P < 0.05). The shapes of MSCs changed and immunohistochemical staining for CD27, CD119 and Oct-4 was positive in the experimental group, but both were just the opposite in the control group. CONCLUSION: Pure MSCs can be obtained by Percoll density gradient centrifugation combined with adherent method and identified by dynamically observing stem cell characteristics, HE staining, observation under the transmission electron microscope and immunohistochemical detection of cell markers. MSCs can secrete cytokines such as IL-6, IL-8, G-CSF, SCF, and so on. MSCs cultured in conditions for spermatogonia may show some biological characteristics of spermatogonia.

Animals↗
PubMed2003

[Expression of 5-hydroxytamine receptors in hepatic stellate cell and action of 5-hydroxytamine on biological characteristics of hepatic stellate cell].

OBJECTIVE: To investigate the expression of 5-hydroxytamine receptors in hepatic stellate cells HSCs and action of 5-hydroxytamine on biological characteristics of HSC. METHODS: Liver ex vivo perfusion of collagenase and density gradient centrifugation were used to isolate hepatic stellate cell. RT-PCR was used to detect the expression of 5-hydroxytamine receptor subtypes 1A, 2A, 2B and 3. Western blot hybridization was used to elucidate the effect of 5-hydroxytamine and its 2A receptor antagonist ketanserin and 3 receptor antagonist ondanosetron on expression of transforming growth factor-beta1 (TGF-beta1) and Smad4 in HSC. HSCs were cultured on silicone membrane. The effect of 5-hydroxytamine, ketanserin and ondanosetron on cell contraction were studied. RESULTS: HSC expressed 5-hydroxytamine receptors subtypes 1A, 2A and 2B. 5-hydroxytamine significantly increased the expression of TGF-beta1 and Smad4 in HSC (P < 0.05). This was antagonized by ketanserin, not by ondanosetron. 5-hydroxytamine induced cell contraction in a dose-dependant manner. Ketanserin antagonized this action, but ondanosetron did not. CONCLUSIONS: HSCs express 5-hydroxytamine receptors. 5-hydroxytamine could affect the biological characteristics of HSC through its receptor mediation, and may play a role in the pathogenesis of liver cirrhosis and portal hypertension.

Animals↗
PubMed2005

[Study on biological characteristics of cultured rhesus mesenchymal stem cells].

This study was aimed to isolate and culture rhesus mesenchymal stem cells (MSC), and to analyze its phenotype and biological characteristics. Bone marrow was aspirated from femur of rhesus, mononuclear cells were extracted, the nonadherent cells were removed after 24 hours, adherent cells were subcultured when they grew 80% confluence. After the fifth passage, the cells were used for examination. The phenotypes of MSC were analyzed by flow cytometry, differentiated cells were identified by relevant specific staining. Cytokines' mRNA expressed by MSC were detected by RT-PCR. The results showed that rhesus MSC gave rise to a population of adherent cells characterized by the presence of a predominant cell type with a typical fibroblast-like morphology. During the log phase of growth, MSC proliferated to a two-fold population at 31 - 40 hours. MSC could be ex vivo expanded by successive cycles of trypsinization, seeding, and culture. The phenotypes expressed on rhesus MSC were Flk-1, CD29, CD105, CD166 positive and CD34, CD45, CD33 nearly negative. In various induction differentiation conditions, rhesus MSC could differentiate into the osteoblast and lipocyte. IL-6, TGF-beta were highly expressed, TNF-alpha was lowly expressed and IL-2, Fas-L, IFN-gamma were not detected on rhesus MSC using RT-PCR method. It is concluded that rhesus MSC can be successfully isolated and culture-expanded and the biological characteristics of rhesus MSC are similar to those of human MSC.

Adipocytes↗
PubMed2003

[Biologic characteristics of intraperitoneal transplantation model of human ovarian carcinoma in severe combined immunodeficiency mice].

OBJECTIVE: To develop a human ovarian carcinoma SKOV3 model in severe combined immunodeficiency (SCID) mouse and to study its biologic characteristics. METHODS: Human ovarian carcinoma SKOV3 cells were injected intraperitoneally into female SCID mouse to establish a transplantation model of human ovarian carcinoma. The biological characteristics, metastasis and morphology of transplanted tumors were studied. RESULT: All tumors grew progressively with no sign of regression. The tumor cells spread around the peritoneal cavity and mainly on the diaphragm, mesentery, peritoneum and around the liver, which was confirmed by histopathology. The morphology, growth pattern and CA125 secretion of primary culture of transplanted cells remained as same as those of ovarian carcinoma cell line SKOV3. CONCLUSION: An intraperitoneal transplantation model of human ovarian carcinoma SKOV3 in SCID mice has been developed successfully, which can simulate the biological behavior of peritoneal metastasis of human ovarian carcinoma.

Animals↗