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Lewis lung carcinoma and two transplantable sarcomas in mice as experimental therapy models: biological characteristics and cell population kinetics.

The biological characteristics of three transplantable tumours: two sarcomas (SaL, MCA) and Lewis lung carcinoma (LLC) have been studied. We investigated histology, DNA ploidy and cell kinetics parameters of the tumours. All examined tumours were aneuploid and rapidly proliferating, with the hyperdiploid fraction greater than 60%. The SaL tumour was found to have the lowest mean aneuploid bromodeoxyuridine labelling index (LI) equal to 21%, while the highest LI of 35.8% was measured for the LLC tumour. The mean S-phase time was short, lasting 8.5 - 10.9 hrs. The potential doubling time (T(pot)) assessed by BrdUrd staining and flow cytometry were as follows: 37.1 hours for SaL, 22.7 hours for MCA and 21.4 hours for LLC tumour. The MCA had the shortest volume doubling time (T(d)) equal to 1.7 days and the longest one, equal to 4.7 days, was found for the LLC. The lowest cell loss was found in the MCA tumour (44%), while the highest in the LLC tumour (81%). As all the examined tumours proliferate rapidly, there is a capacity for accelerated repopulation and therefore the tumours seem to be good models for experimental radiotherapy.

Animals↗

Multivariate data analyses of chlorinated and brominated contaminants and biological characteristics in adult guillemot (Uria aalge) from the Baltic Sea.

Adult guillemot (Uria aalge) birds, 10 females and 10 males, drowned in trawl nets near Stora Karlsö in the Baltic Sea, were collected in 2000. Several of the animals' biological characteristics were recorded. The birds' pectoral muscles were individually analyzed for their concentrations of organochlorines (OCs) and brominated flame retardants (BFRs), dichlorodiphenyltrichloroethanes (DDTs), polychlorinated biphenyls (PCBs), hexachlorocyclohexanes, trans-nonachlor, hexachlorobenzene, hexabromocyclododecane (HBCD), and polybrominated diphenyl ethers (PBDEs). The dominating contaminant was p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) with a geometric mean concentration of 12 900 ng/g lipid weight (lw). The concentration of sigmaPBDE (80 ng/g lw) was similar to that of HBCD (65 ng/g lw). The total concentration of all OCs was approximately 150 times higher than that of all BFRs. For the statistical evaluation of the data, we used multivariate analysistechniques such as principal components analysis, partial least-squares (PLS) regression, and PLS discriminant analyses. No differences between the two sexes were found, either in contaminant concentrations or in biological characteristics. We found that some biological characteristics covaried with the concentrations of several OCs and BFRs, e.g., a negative correlation between liver weight and concentration of contaminants. The concentrations of most OCs but not of BFRs showed a decrease with increasing lipid content. Further, a PLS model with OCs as X and BFRs as Y showed that the contaminants formed two groups, each with distinctive correlation patterns. The PLS model could be used to predict with varying accuracy the concentration of BFRs in the individual muscles from their concentration of OCs.

Animals↗

Effects of soybean (Glycine max) germination on biologically active components, nutritional values of seeds, and biological characteristics in rats.

We briefly reviewed the effects of soybean germination on biologically active components, nutritive value of seed and biological characteristics in rats. The purpose of this review is to evaluate the effects of soybean germination on nutritional values of seeds and the potential importance for the use of germinated soybeans, from a contemporary conception, in food preparation as well as on soybean possible influence in optimal health. Germination induced a substantial increase in the content of saponin, oestrogenic compounds and almost all phytosterols, particularly beta-sitosterol of seeds. Lecithin content increased slightly and gradually during germination process. Lipase and alpha-galactosidase activities increased whereas lipoxygenase activities reduced after a short period of germination (< or = 72 h). Therefore, the substantial odour and flavour scores of germinated soybean flour were improved. Germinated seeds were also beneficial to heat penetration, their thermolabile antinutritional factors were easier to inhibit than those of dry beans, also the seeds did not require a long cooking time to be palatable. Duration of the germination process greatly influenced the nutritional value and palatability of seeds and biological characteristics in rats. In rat bioassay, one-day germination of soybeans induced a significant increase of daily body weight gain, daily protein intake in rats and protein efficiency ratio (PER) of seed meal. Palatability of seeds was also improved whereas a 5-day germination resulted in a decrease of PER of seed meal (less than the value of unheated seeds) and induced thyroid enlargement in rats. A vapour thermal treatment (100 degrees C, 20 min) eliminated thyroid-active agents and improved PER of seed meal, food intake and final weight of rats. Well prepared germinated soybeans can be used as a good alternate to animal proteins for more balanced nutritional diet. Development of food products from germinated soybean may be another way to further increase the versatility and utility of soybeans for both developing and industrialized countries, as germination induced the modification of certain specific biologically active components, palatability and nutritive value of seeds.

Animals↗

[Culture and comparison of the biological characteristics of human junctional epithelium and gingival epithelium].

PURPOSE: To study the different biological characteristics of human junctional epithelium (JE) and gingival epithelium (GE). METHODS: Human JE cells were cultured and identified by the cell culture and immunohistochemistry, and the biological characteristics of JE cells and GE cells were compared. RESULTS: The morphology of cultured JE cells was various and unequal, the arrangement of the cells was loose and mitosis was common, while GE colony was consisted of equal and closely packed epithelial-like cells in a paving stone arrangement. CK-Pan staining was positive in all JE and GE cells. CK19 was strongly stained in all JE cells but only moderately stained in some GE cells, and most GE cells were negative which was obviously different from JE cells. JE cells had longer latent period (7 days) than GE cells (4 days) during the cell growth period, and then the cells proliferated rapidly (4 days) to attain the maximum and descended rapidly in the declining period. While GE cells ascended evenly (7 days) to attain the maximum and descended slowly in the declining period. Proliferation study demonstrated the doubling time of JE cells was 48 to 60 hours and that of GE cells was 72 to 96 hours. It was possible to subculture JE cells up to 5 times serially, and that of GE cells was up to 7 times. CONCLUSIONS: The human JE cells are a kind of unique non-differentiated epithelial cells different from GE cells. In this experimental culture condition the subculture times of JE cells were less than GE cells, which affects JE cells, so the culture methods and conditions should be improved.

Cell Proliferation↗

Biologic characteristics of cultured human vitiligo melanocytes.

BACKGROUND: Vitiligo is a pigmentary disorder of unknown cause characterized by depigmented patches due to destruction of melanocytes. Recently, the inherent cellular defect theory has been discussed. To investigate the biologic characteristics of cultured melanocytes from normal and vitiligo subjects, this study had the purpose to examine the functional and ultrastructural characteristics of these melanocytes and to observe the morphologic and functional changes of melanocytes in response to ultraviolet B irradiation. METHODS: Melanocytes were isolated and cultured from foreskin and arm skin of normal and vitiligo subjects. The DNA synthesis, tyrosinase activity assay, transmission and scanning electron microscopic examination, and the effects of ultraviolet B(UVB)-irradiation on cultured melanocytes were studied. RESULTS: Vitiligo melanocytes showed no significant differences in DNA synthesis and tyrosinase activity compared with normal melanocytes, but the vitiligo melanocytes contained dilated and/or circular rough endoplasmic reticulum (RER) on transmission electron microscopic examination. Exposure of the cultured melanocytes to UVB resulted in increased protein synthesis and tyrosinase activity. Morphologic alterations and changes in DNA synthesis were also noted. Compared with normal melanocytes, the responses of vitiligo melanocyte to UVB showed no significant difference. CONCLUSIONS: Normal and vitiligo melanocytes showed similar biologic characteristics except in the changes of RERs in the vitiligo melanocytes. The ultrastructural aberrations in vitiligo subjects do not seem to be directly related to the biologic characteristics and the responses to UVB irradiation in vitiligo melanocytes.

Cell Division↗

[Biological characteristics of different forest soils in Nanjing-Zhenjiang mountan area].

Studies on the biological characteristics, including soil microbe, soil enzyme activity, soil nutritient content, and litter decomposition of different forest soils in Nanjing-Zhenjiang mountain area showed that the amounts of microbes and the activities of six enzymes in forest soils changed regularly in different forests during different months. The contents of nutritional elements varied regularly with forest growth bio-cycles, and were inerrelated prominently with the amounts of soil microbes and the activities of soil enzymes. There existed temporal-spatial differences in the decomposition rate of litters and the reverted velocity of nutrients among different forests. The comparisons of various biological characteristics among secondary Quercus variabilis forest, Phllostachys pubescens forest, and Cunninghamia lanceolata forest indicated that secondary Quercus variabilis forest had the most abundant nutrients in soil, and possessed the strongest ability of self-fertilization. Therefore, to construct coniferous forests with broadleaf trees in this area could avoid or abate the decline of soil fertility.

Biomass↗

[Biological characteristics of an established model of ovarian cancer in mice and its homologous cell lines].

BACKGROUND & OBJECTIVE: There are no specific methods for early diagnosis of ovarian cancer, recurrence prevention and drug-resistance. The experimental mouse model of ovarian cancer could help to reveal the biological and genetic features of ovarian cancer, and provide rational basis for further intervention strategy. This study was to establish a model of ovarian cancer in mice and homologous cell line, and analyze its biological characteristics. METHODS: Ovarian cancer was developed in 8-week-old female F1 (C57BL/6N x C3H/He) mice by a single whole-body neutron irradiation of 2.7 Gy from a (252)Cf source. A metastatic cell line was established through serial subcutaneous transplantation of the primary tumor for 11 generations, and then tumor cells were transferred to in vitro cultivation. These cells were cloned for more than 6 months. The biological characteristics of the tumors and the homologous cell line were determined by cellular and molecular biological techniques. RESULTS: The grafted tumors in mice were successively passaged for 11 generations with a successful inoculation rate of 96% during 23 months. A tumor cell line OV99 isolated from the grafted tumors was established after 6 months and grew steadily. Morphologic characters and ultrastructures of OV99 cells were accorded with those of ovarian cancer epithelia. The chromosomal analysis of OV99 cells revealed aneuploid pattern of 76 chromosomes. Flow cytometry (FCM) and reverse transcription-polymerase chain reaction (RT-PCR) showed same features between OV99 cells and positive control ovarian cancer cell line OVHM, including distribution of cell cycle, rapid growth rate and the expression of P21, P185, P53, proliferating nuclear cell antigen (PCNA) and Cyclin D proteins, and MAGE-1 and MAGE-3 mRNA. CONCLUSION: Establishment of the ovarian carcinoma animal model in mice and OV99, a cell line owns biologic characteristics of ovarian cancer cells, provides experimental materials for further investigation of ovarian carcinoma.

Animals↗

[Molecular biological characteristics and genetic significance of Yersinia pestis in China].

OBJECTIVE: To understand the molecular biological characteristics in order to analyse the genetic background of Yersinia pestis in China. METHODS: Primary datum on ribotyping, pulsed field gene electrophoresis (PFGE), random amplified polymorphic DNA (RAPD) and insertion sequence (IS) of Yersinia pestis were used and under cluster analysis. Genetic interval and various methods of recognized molecular feature between different strains were evaluated. RESULTS: Ribotypes the PFGE types seemed to be corresponding. Stains from Microtus fuscus and area in Tibet Zhongba belonged to 7 copy rRNA gene and the genetic interval were the far more with 6 copy rRNA gene stains, and not definite with RAPD, but with many exceptions. The genetic interval between strains were showed by resemble value. CONCLUSION: Yersinia pestis in China had its own manifold, particular molecular biological characteristics due to natural barriers, geographical complex, circumstances in Tianshan Mountains and Gandise Mountains areas. Yersinia pestis were limited to separateness, evoluted only in certain areas to form a great many gene types.

Animals↗

[Study on the biological characteristics of permethrin-resistant and susceptible strains of Culex pipiens pallens].

OBJECTIVE: To compare the biological characteristics of Culex pipiens pallens between permethrin-resistant strain and the susceptible strain. METHODS: In laboratory, the biological characteristics about bloodsucking, reproduction and development of permethrin-resistant and susceptible strains were observed and recorded. Life table of the experimental populations was constituted. RESULTS: The bloodsucking rate of resistant strain was lower than susceptible strain and the difference was significant. The life-span of adults of resistant strain and the developmental duration of eggs, larvae and pupae were longer than susceptible strain and the difference was significant. The death rate of eggs of resistant strain was higher than that of susceptible strain and the difference was significant. The permethrin-resistant strain showed a fitness value of 0.58 relative to the susceptible strain. CONCLUSION: The permethrin resistance of Culex pipiens pallens may result in a disadvantage to its reproduction and development.

Animals↗

[Retrospective study of acute myelogenous leukemia in 83 elderly patients: clinical and biological characteristics].

In order to characterize clinical and biological characteristics of elderly patients with acute myelogenous leukemia (AML), we retrospectively analysed 83 elderly patients aged 60 years or more and, as a control, 114 younger patients aged 15 to 59 years who were admitted to our hospital between August 1984 and January 1998. There was a significantly higher incidence of preceding myelodysplastic syndromes in the elderly patients. They also had a significantly higher incidence of unfavorable cytogenetic abnormalities (loss or partial deletion of chromosome 5 or 7) and a significantly lower incidence of favorable cytogenetic abnormalities, such as t(15:17), t(8:21), or inv(16). With regard to FAB subtypes in de novo AML, the incidence of M3 subtype was significantly lower in the elderly group. Myeloperoxidase positivity of AML cells in the elderly group was lower than that in the younger group. Laboratory data at presentation disclosed a lower peripheral leukemic cell count, a higher fibrinogen level, a lower serum protein level, and a higher serum creatinine level in the elderly group. They also had poorer performance status and more frequent concomitant diseases at presentation, including liver diseases, heart diseases, or documented infections. It was concluded that elderly AML patients 60 years or older had a higher incidence of poor prognostic factors compared to younger patients.

Adolescent↗

[Culture of human fibroblasts transfected by human telomerase reverse transcriptase eucaryotic expression plasmid pGRN145 and their biological characteristics in vitro].

OBJECTIVE: To analysis the biological characteristics of human fibroblasts transfected by human telomerase reverse transcriptase (hTERT) eucaryotic expression plasmid pGRN145. METHODS: Fibroblasts from children's foreskin were isolated and cultured in vitro, and the fibroblasts were transfected by pGRN145 with Lipofec-tAMINE PLUS Reagent. After strict screening of hygromycin B, the positive clones were subcultured. The telomerase activity was detected by RT-PCR and TRAP-PCR technique. The cell generation cycle and apoptosis rate were detected by flow cytometry to investigate the proliferative characteristics after transfection, and the chromosome karyotype of transformed cells was analyzed. The collagen secreted by transformed cells was detected by immunohistochemical staining. RESULTS: The morphological properties of fibroblasts did not change obviously after transfection. There were telomerase activity in transfected fibroblasts, while it could not be detected in pre-transfection fibroblasts. The cell generation cycle had no obvious changes between pre-transfection and post-transfection. However, the apoptosis rate of transfected fibroblasts were decreased compared with that of pre-transfection. The fibroblasts transfected by pGRN145 maintained the normal diploid karyotype, as well as the cells could normally secret type I and III collagen. CONCLUSION: The human fibroblasts transfected by pGRN145 has telomerase activity with prolonged life span of culture, which preliminarily proves the availability of establishing standard seeding cell lines of tissue engineering by hTERT plasmid transfection techniques.

Apoptosis↗

[Role of paratypical factors in determining human multiple pregnancy. I. A comparative statistical analysis of the social biology characteristics of the mothers].

Twelve social-biological characteristics were investigated in 400 mothers of monodizygotic twins and in 429 women in the control group. The mean age of mothers for dizygotic types of twins was, on the whole, authentically higher than that of the control women. The continuance of the working activity, the character of the work, inclination towards certain food have been reported to influence the manifestation of being a dizygotic twin. In addition to the above mentioned factors, the age of women at the beginning of their sexual life is of importance. Also, a woman's psychological attitude towards the possible pregnancy is reported to influence multiple pregnancy. The percentage of repeated marriages among twins mothers was higher than that in the control group. Conclusions are made on the use of the factors investigated for a probable estimation of manifestation of multiple pregnancy.

Age Factors↗

[The effects of tumor antigen gene OVA66 on biological characteristics of tumor cells].

AIM: To explore the effects of tumor antigen gene OVA66 on the biological characteristics of tumor cells. METHODS: The eukaryotic expression vector pcDNA3.1-mock and recombined vector pcDNA3.1-OVA66 were transfected into hepatoma cell line SMMC-7721 by LipofectAMINETM 2000. After stable selection and clone proliferation of cells, the expression of OVA66 gene and protein was detected by RT-PCR, Western blot and immunocytochemical (ICC) staining. The cell growth cycle was analyzed by FACS. The ultrastructure was observed under electron microscope. The experiments in cell migration and invasion were performed in vitro. The OVA66-associated genes were analyzed by genechip technique after gene transfection. RESULTS: OVA66 was highly expressed in 7721 cells transfected with pcDNA3.1-OVA66 at mRNA level. Western blot result demonstrated that OVA66 protein content was notably increased compared with that in control cells. Electron microscope and FACS results indicated that OVA66 gene promoted the growth and proliferation of tumor cells. In vitro, the experiments in cell migration and invasion showed that this gene enhanced migration and invasion of tumor cells. The result of genechip demonstrated that the over- expression of OVA66 gene increased the expression of plasminogen activator inhibitor-1 gene (PAI-1), suggesting that it had some effects on tumor invasion and metastasis. CONCLUSION: Tumor antigen gene OVA66 and it's protein demonstrate a series of biological characteristics of tumor cells, which can promote the proliferation, migration and invasion of tumor cells.

Antigens, Neoplasm↗

Biological characteristics of CD7 positive acute myelogenous leukaemia.

We studied the biological characteristics of CD7+ acute myelogenous leukaemia (AML). We diagnosed nine out of 88 consecutive AML cases as CD7+ AML based on myeloperoxidase positivity and surface antigen expression. In eight of these nine cases more than 20% of leukaemic blasts were found to coexpress both CD7 and a myeloid-associated antigen, CD33, by a two-colour flow-cytometric assay, while in the remaining case more than 90% of blasts were positive for CD7 and myeloperoxidase. CD7+ AML was most frequently observed in M1 among AML subtypes according to the FAB classification. An early stage-specific antigen, CD34 was also expressed on leukaemic blasts from eight of these nine cases. Neither the T-cell receptor (TcR)-beta nor the TcR-gamma gene was clonally rearranged in any of the cases. We then studied the proliferative responses to stimulation by various growth factors. Among interleukin-3 (IL-3), granulocyte/macrophage colony-stimulating factor (GM-CSF), and granulocyte-CSF (G-CSF), IL-3 showed the strongest stimulatory effect on DNA synthesis and leukaemic blast colony formation in 8/9 and 6/8 CD7+ AML cases examined, respectively. On the other hand, the strongest stimulatory effect exerted by IL-3 on blast colony formation was observed in only six out of the 33 CD7- AML cases examined. Furthermore, CD7+ AML blasts could proliferate in response to stem cell factor (SCF); SCF alone showed stimulatory effects on blast colony formation (7/8 cases), and in 5/7 SCF-responding cases, stimulatory effects of SCF were more potent than those of IL-3. In addition, SCF enhanced blast colony formation synergistically with IL-3 in four of these seven cases. These data suggest that progenitor cells of CD7+ AML may possess the biological properties characteristic of immature haematopoietic stem cells.

Adolescent↗

In vitro culture and study of the biological characteristics of rabbit keratocytes.

OBJECTIVE: To improve the technique for culturing rabbit keratocytes in vitro and investigate the biological characteristics of these cells. METHODS: Fresh rabbit corneas were obtained and the epithelial and endothelial cells were removed after digestion with trypsin. The stroma was rinsed, minced, and incubated in DMEM/F12 medium supplemented with 10% fetal bovine serum and the biological characteristics of the keratocytes were observed with MTT assay and compared with those of the cells in serum-free culture media. RESULT: On about the third day of incubation, some keratocytes germinated from the stromal tissues and migrated onto the flask surface presenting fibroblast-like arrangement with spindle-shaped appearance. The keratocytes became confluent after 10 day's incubation and the peak of cell proliferation occurred on day 8 in the presence of serum in the media, while in the absence of serum, the peak took place on day 10. CONCLUSION: The method improved for in vitro keratocyte culture is convenient and effective, and the presence of serum in the media may to some degree affect the growth of the keratocytes.

Animals↗

Biological characteristics of HCC by ultrasound-guided aspiration biopsy and its clinical application.

AIM: To probe the pathological biological characteristics of hepatocellular carcinoma (HCC) by the ultrasound-guided aspiration biopsy and assess the clinical application value of this method. METHODS: The biopsy and DNA analysis by flow cytometry (FCM) were taken in 46 cases with HCC nodules, including 26 cases and 20 cases with nodules < or =3 cm and >3 cm in diameters respectively, and 12 cases with intrahepatic benign hyperplastic nodules. They were taken in 22 cases of 46 cases with HCC before and after the therapy. Fine-needles and automatic histological incised biopsy needles were used. The fresh biopsy tissue was produced into the single cell suspension, which was sent for DNA detection and ratio analysis of cell period. The ratio of each DNA period of cell proliferation of each group was calculated and compared with each other. The DNA aneuploid (AN) and apoptosis cell peak were observed and their percentages were calculated. RESULTS: The ratios of S and G(2)/M periods of DNA, which reflect cell hyperproliferation, in the group with HCC tumors >3 cm in diameter were markedly higher than those of the group with HCC nodules < or =3 cm in diameter and the group with the benign hyperplastic nodules (P<0.01 except A:B of S period, P<0.05). The ratios of the middle group were also apparently higher than those of the latter group (P<0.01). The ratio of DNA AN of 46 cases with HCC nodules was 34.8 % (16/46). None of the cases with the intrahepatic hyperplastic nodules appeared AN. The DNA AN appeared more apparently with the growth of the tumors. The AN ratio of the group with tumors >3 cm in diameter was 55 % (11/20), markedly higher than that of the group with tumors < or =3 cm in diameter which was 19.2 % (5/26) (P<0.01). The FCM DNA analysis of 22 specimens of hepatic carcinoma tissue before therapy showed that the aneuploid peaks appeared in 5 cases (22.7 %). The ratio of G(1) period rose after therapy while the S period and G(2)/M ratios fell (P<0.01). The aneuploid peak disappeared in the 5 cases after the therapy, while the apoptosis peaks in 12 cases (54.5 %) appeared. CONCLUSION: Addition to supply the information of the pathological morphology of the tumor, the ultrasound-guided fine-needle aspiration tissue could be sent for FCM DNA analysis to comprehend its pathological biological characteristics. This can not only provide the clinic the reliable information about the occurrence, development, diagnosis, curative effect and prognosis of tumors but also supply biological information for clinic to choose therapeutic schemes.

Adult↗

[Analysis of the biological characteristics of primary HIV-1 isolates using the main components method].

The principal component method is verified for analysis of categorized biological characteristics of HIV-1 variants. Thirty wild isolates of HIV-1 are studied. The method notably facilitated comparative analysis of a large scope of experimental data. Using this method, it is possible to detect a relationship between the biological characteristics and results of other taxonomic schemes, to distinguish the factors restricting the biological signs, to single out the most informative signs for describing a given set of isolates, and to define the criteria for comparing the properties of two sets of virus isolates and selecting the isolates notably differing from each other for more thorough phenotyping.

Cell Line↗

Biological characteristics and host influence on a geographical isolate of Trichinella (wolverine: 55 degrees 00'N, 100 degrees 00'W, 1979).

Biological characteristics of Trichinella isolate (wolverine: 55 degrees 00'N, 100 degrees 00'W, 1979) were established in Crl: COBS CFW (SW) mice. Comparison of the wolverine isolate's biological characteristics with another Trichinella isolate (polar bear), both from closely related geographic areas, revealed there were stable and reproducible genetic differences between isolates. Differences were most pronounced for degree of infections causing a 50% mortality of mice, larval production by females in vitro, reproductive capacity indices, and survival of muscle larvae. Species and strain of host altered characteristics of the wolverine isolate such as worm position, sex ratios, % recovery, larval production by females in vitro, and reproductive capacity indices. Genetic differences between isolates of Trichinella and interaction with host genetics raises interesting questions on Trichinella speciation. Differences reported here, are best interpreted for the time being at least, as part of the normal biological variability of the species Trichinella spiralis.

Animals↗