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Clinical and biological characteristics of clear cell carcinomas of the ovary in FIGO stages I-II.

Clear cell carcinoma of the ovary is considered to be a specific subtype among the epithelial ovarian malignancies. To characterize clear cell carcinomas in early FIGO stages (I-II) with regard to clinical and biological properties, a retrospective study was performed to compare these tumors with other histological subtypes. From a complete series of 226 patients with epithelial ovarian carcinomas in FIGO stages I-II, 28 patients with clear cell carcinomas were selected and the clinical and biological characteristics of these tumors were compared with the remaining non-clear cell carcinomas. All patients underwent primary staging laparotomy followed by adjuvant radiotherapy or chemotherapy. The apoptosis regulators p53, bcl-2 and bax, and the growth factor receptors EGFR and HER-2/neu were analyzed by immunohistochemical techniques and DNA analysis was performed by flow cytometry. Clear cell carcinomas stained negative for p53 significantly more often than other histological subtypes. Positive EGFR staining was seen more frequently in serous carcinomas than in the clear cell carcinomas. Aneuploid DNA status was seen more frequently in clear cell carcinomas than in other histological subtypes and tetraploid tumors made up 50% of the non-diploid tumors. Clear cell tumors were frequently (64%) found in FIGO stages IC and IIC and this was more common than for non-clear cell tumors. No difference was found in the rate of tumor recurrences or survival for patients with clear cell and non-clear cell carcinomas. Clear cell carcinomas of the ovary should be regarded as a separate entity among the epithelial ovarian carcinomas and they differ with regard to both clinical and biological characteristics when compared with non-clear cell tumors.

Adenocarcinoma, Clear Cell↗

[Some differences on biological characteristics of Campylobacter jejuni].

Fecal samples from 195 diarrheic patients in different age, rectal and cloacal swabs from 656 normal and diarrheic animals and poultry, 108 visceral materials from the dead animals with diarrhoea were cultured for Compylobacter jejuni. A total of 458 strains of campylobacters (445 strains of C. jejuni, 13 strains of C. coli) were isolated and identified, and some biological characteristics of these strains were observed. Lior's biotyping scheme was used for biotyping 354 strains of campylobacters(253 strains of C. jejuni and 2 strains of C. coli). The results showed the most biological characteristics of these campylobacters accorded with that previously described in the literatures, but it were also found that there were some differences on morphological, cultural, physiological and biochemical characteristics and antibiotic resistances. In these differences, the most main differences were that 48.3% (215/445) of C. jejuni and 23.1% (3/13) of C. coli were resistant to nalidixic acid, and that 1.1% (5/445) of C. jejuni and 7.6(1/13) of C. coli were resistant to cefotaxime. There were relationships between antibiotic resistances and strain sources (P < 0.005). The result of biotyping 352 strains of C. jejuni indicated that biotype I (40.9%) and II (58.2%) were predominant in the bodies of these animals, and there were two biotypes distributed in the body of same animal.

Animals↗

Normal physiological conditions maintain the biological characteristics of porcine aortic heart valves: an ex vivo organ culture study.

The aortic valve functions in a complex mechanical environment which leads to force-dependent cellular and tissue responses. Characterization of these responses provides a fundamental understanding of valve pathogenesis. The aim of this work was to study the biological characteristics of native porcine aortic valves cultured in an ex vivo pulsatile organ culture system capable of maintaining physiological pressures (120/80 mmHg) and cardiac output (4.2 l/min). Collagen, sGAG and elastin contents of the valve leaflets were measured and cusp morphology, cell phenotype, cell proliferation and apoptosis were examined. Presence of endothelial cells (ECs) on the leaflet surface was also evaluated. The differences in collagen, sGAG and elastin contents were not significant (p > 0.05) between the cultured and fresh valve leaflets. The cultured valves maintained the native ECM composition of the leaflets while preserving the morphology and cell phenotype. Cell phenotype in leaflets incubated statically under atmospheric conditions decreased compared to fresh and cultured valve leaflets, indicating the importance of mechanical forces in maintaining the natural biology of the valve leaflets. ECs were retained on the surfaces of cultured leaflets with no remodeling of the leaflets. The number of apoptotic cells in the cultured leaflets was significantly (p < 0.05) less than in the statically incubated leaflets and comparable to fresh leaflets. The sterile ex vivo organ culture system thus maintained the viability and native biological characteristics of the aortic valves that were cultured under dynamic conditions for a period of 48 h.

Animals↗

[Studies on biological characteristics of enterovirus type 70 (EV 70)].

Enterovirus type 70 (EV 70) is a new type of enterovirus, which is a causative agent of "Acute Hemorrhagic Conjunctivitis" (AHC). It appeared for the first time in Ghana in 1969, and occurred in Japan in 1971. The optimal temperature for growth of EV 70 is 33-35 degrees C, and lower than that of other enteroviruses. Ninety two isolates of EV 70 were investigated to know the biological characteristics. Isolates were obtained in Japan and foreign countries in Africa, Asia and Europe in 1971-1981, and contained eighty seven from eye swabs, three from feces and two from throat swabs. Reproductive capacity of EV 70 at 38 degrees C varied from one isolate to the other. The ratios in log of 33 degrees C yield to 38 degrees C yield ranged from 0.2 to 3.2, and showed no tendency to obtain reproductive capacity at high temperature chronologically after invasion to Japan. In order to find whether EV 70 obtains the reproductive capacity at 38 degrees C, three isolates, which had high pfu ratios (33 degrees C/38 degrees C, log), 2.6-3.2, were subjected to 5 passages by plaquing method. It was found that they obtained the capacities remarkably, and the ratios decreased to -0.5-0.6. As EV 70 exhibits a physicochemical characteristic of enteroviruses, the reproductive capacity in organ cultures of human fetal small intestine was investigated. The results indicated that EV 70 isolates grew distinctly, though the degree of that was less in comparison with coxsackievirus B1 and echovirus 11, and that they increased in the capacities by passages in the intestine. These findings suggested that EV 70 developed the reproductive capacities at high temperature and that in human intestine experimentally. By neutralization tests using two kinds of antisera against EV 70, it was found that serological characteristics of EV 70 changed after invasion to Japan. Intratypic antigenic mutants were first isolated in some parts of Honshu areas in 1972, and took the place of prototype-like isolates throughout Japan in the following one or two years, and after that, no prototype-like isolates obtained anywhere. The same trend was observed in isolates in foreign countries. To investigate differences and changes of these biological characteristics of EV 70 more precisely, further observations seemed to be necessary.

Enterovirus↗

The biological characteristics of a water soluble porphyrin in rat lymph nodes.

The biological characteristics of a radiolabeled metalloporphyrin, 5,10,15,20-tetrakis(4-carboxyphenyl)-porphinato [67Cu]copper (II) [( 67Cu]TCPP), in rat lymph nodes, surrounding muscle, fat, and blood were determined. Lymphatic tissue localized greater amounts of [67Cu]TCPP than did surrounding muscle and fat. Inflamed lymph nodes localized greater amounts of [67Cu]TCPP than did noninflamed lymph nodes. Time course studies suggest that the uptake of [67Cu]TCPP in noninflamed and in inflamed lymph nodes may involve different biological processes. The affinity of [67Cu]TCPP for inflamed lymph nodes may be influenced by the degree of inflammation. If further studies confirm these results, [67Cu]TCPP may be useful as a potential radiopharmaceutical for imaging inflamed lymph nodes.

Adipose Tissue↗

Small hepatocellular carcinoma. DNA content and biological characteristics.

The DNA content of 12 small hepatocellular carcinomas (SHCC, less than 3 cm in diameter) and 26 large hepatocellular carcinomas (LHCC) was quantitatively determined by means of TV-image analysis. The results showed that 8 patients (66.7%) with SHCC had DNA stem lines in diploid (2C), and 24 (92.3%) with LHCC had DNA stem lines in aneuploid (AN) (P less than 0.01). The incidences of tumor capsule breaking and cancerous thrombosis were 16% and 20% respectively in SHCC, significantly lower than 84% and 80% in LHCC (P less than 0.01). The 5-year survival rate was 75% in patients with SHCC after operation, much higher than 46.2% in patients with LHCC. No relations were found between DNA content, tumor size, pathological grading and serum AFP values of HCC. The results suggest that SHCC less than 3 cm in diameter reflects the early changes of biological characteristics; HCC of 3 cm in size may be at an important period when the changes of DNA stem lines and biological characteristics would occur; SHCC is possible to be determined by serum AFP values; and that the survival rate of the patients can be further improved by early finding and treatment of SHCC less than 3 cm in diameter.

Carcinoma, Hepatocellular↗

[Molecular biology characteristics of ESBL-positive strains of Klebsiella pneumoniae collected in the Neonatal Unit of the Teaching Hospital in Olomouc].

BACKGROUND: One of the problems of contemporary medicine is an increasing number of bacterial strains with hazardous phenotypes of resistance. This is also true for neonatal units where nosocomial infections caused by multiresistant bacteria pose a serious threat to newborns. The feared bacterial pathogens include Klebsiella pneumoniae strains producing AmpA Extended-Spectrum Beta-Lactamases. The study focused on the molecular biology characteristics of ESBL-positive strains of K. pneumoniae collected in the Neonatal Unit of the Teaching Hospital in Olomouc (THO). MATERIALS AND METHODS: Clinical material from newborns hospitalized in the THO Neonatal Unit between January and June 2004 was used to isolate and determine K. pneumoniae strains by standard identification procedures. Their susceptibility to antibiotics was tested using a dilution micromethod. A Double-Disk Synergy Test was used for phenotype determination of ESBL production. The bla gene coding ESBL production was demonstrated by PCR. Molecular biology characteristics of ESBL-positive strains utilized the genomic DNA isolation, XbaI restrictase digestion and PFGE differentiation. The acquired restriction maps of individual isolates were compared using the GelCompare software and their relationship was determined. The selection pressure of antimicrobial agents was assessed according to the absolute number of defined daily doses of individual antibiotics. RESULTS: During the monitored period, 112 K. pneumoniae strains were isolated in total. In 22 of them (19.6%), the TEM-type ESBL production was determined. ESBL-positive strains were only observed in upper respiratory tract and rectal swabs collected from newborns with no signs of infection. The molecular biology analysis showed that 21 ESBL-positive strains had an identical restriction profile, i.e. they were very likely to be identical. The selection pressure of third- and fourth-generation cephalosporins was very low over the observed period and their consumption accounted for 1.9 % of all administered antimicrobial agents. CONCLUSION: The results presented above suggest that ESBL-positive strains of K. pneumoniae occurred in the THO Neonatal Unit due to clonal and horizontal spread from an unidentified source.

Cross Infection↗

[Biological characteristics of Proteus strains isolated from water sources in the Azerbajiani SSR].

Biological characteristics of 102 Proteus strains isolated from the water bodies is given. The strains studied were referred to Pr. mirabilis, more rarely to Pr. vulgaris; about half of the cultures deviated from these biological types by the signs of indol formation and maltose fermentation. Proteus of groups O3, O5, O13, O23, and O30 were revealed in studying the serological characteristics. All the cultures were polyresistant, nonbacteriocinogenic; most of them were sensitive to the wide colicine spectrum. One strain produced a cytopathogenic action on the tissue culture.

Anti-Bacterial Agents↗

[Biological characteristics of hyperleukocytic acute leukemia].

The study was to investigate the biological characteristics of hyperleucocyte acute leukemia (HAL) and its clinical significance. Immunophenotyping was performed in 48 HAL patients and 73 NHAL patients by three-color flow cytometry analysis using CD45/SSC gating, meanwhile the cytogenetic analysis was performed in 74 patients. The results showed that as compared with NHAL group, HAL group had lower proportion of eryth-lineage in bone marrow (P < 0.05); in AML, the CD14 expression of HAL group was apparently higher than that of NHAL group (P < 0.05); in ALL, HAL group had higher expression of CD8 and lower expression of CD22, cCD79a compared with NHAL group (P < 0.05); the two groups had no significant difference in expression of special lineage antigens and overlapping lineage antigens (P > 0.05). The CR rate of HAL group was lower than that of NHAL group. It is concluded that bone marrow inhibition of HAL group is more severe than that of NHAL group. In AML, monocytic leukemia is easier to become into HAL than other leukemias. In ALL, T-lineage antigens of HAL group are more easily expressed than those of NHAL group; the leukemia cells of HAL group are naiver than those of NHAL group, meanwhile the prognosis of HAL is poor.

Adolescent↗

[Study on biological characteristics and relative yield of Ophiopogon japonicus].

OBJECTIVE: To study the biological characteristics and the relative yield of Ophiopgon japonicus. METHOD: The observation of the selected plants nad determination of the selected samples. RESULT: The yield of O. japonicus was positively correlated to the height of plant, the weight of leaves, the length of nutritive roots, and the quantity of root tubers. It was also positively correlated to the weight of nutritive roots, but not significantly. CONCLUSION: According to the growing characteristics of O. japonicus, the yield of O. japonicus can be promoted by selecting porous soil, controlling the field water from planting to the middle 10 days of June and enhancing the management of fertilizer and water from July to November and from the end of February to early in March next year.

Biomass↗

Studies on lymph humoral factor. Biological characteristics of a lymphocytopoietic factor in rat thoracic duct lymph.

The biological characteristics of a lymphocytopoietic factor obtained from rat thoracic duct lymph (Yamashita, Fukumoto & Miyamoto, 1976) were further investigated. The lymph extract from normal rats failed to stimulate both large pyroninophilic cell-proliferation and mitotic response in the spleen and lymph node of the thymectomized, irradiated and marrow reconstituted rat (B rat). This suggests that target or responsive cells for the factor are not marrow-derived (B) cells, but thymus-derived (T) cells. On the other hand, the lymph extract from the lymphopenic lymph-drained B rats showed similar high lymphopoietic activity to those of normal rats, indicating that the existence of a thymus is not essential for the production or secretion of the factor. The fact that lymphocytotic rats produced by syngeneic lymphocyte transfusion are most sensitive to the lymph extract suggests that liver endogenous level of this factor and the responsiveness of target cells are regulated by the number of circulating T lymphocytes.

Animals↗

[Biological characteristics of Ligusticum chuanxiong Hort].

Observational studies were conducted on the biological characteristics of Ligusticum chuanxiong, such as suitable growth environment, growing period, growth of stems, leaves and rhizomes, yield structure, etc. The specific regularities of each growth period were also studied.

Plants, Medicinal↗

[Definitions of biological characteristic quantities].

In this paper, the interaction is searched between a new biological field and a growing organism. There are just yielded many analogies to mechanic and electrodynamic. The special comparison between a biological axiom previously defined and the OHM's Law shows deep analogies to electrotechnic. Through that it's possible to understand better the new already used terms. With help by this comparison special electronical definitions can take over into biology. 2 examples shown the construction of statical biological characteristics from which altogether 10 characteristic values can derivated. Finally, a list shows all important relations of the framed hypothesis.

Biology↗

Biologic characteristics of esophageal epithelial dysplasia assessed by proliferating cell nuclear antigen.

BACKGROUND: Proliferating cell nuclear antigen (PCNA) correlates with the cell proliferative state. Using a PCNA specific monoclonal antibody, various malignant neoplasms have been assessed for cell proliferation and malignant potential. However, there are few studies regarding the expression of PCNA in esophageal dysplasia. METHODS: PCNA expression was immunohistochemically determined in resected specimens from 27 patients with superficial esophageal carcinoma that contained areas with various degrees of dysplasia, carcinoma in situ (CIS), and carcinoma invading the mucosal layer. The authors estimated the cell proliferative activity and biologic characteristics of the basal and parabasal cells of these esophageal epithelial disorders. RESULTS: The degrees of PCNA labeling index (PCNA LI) of the basal layers were lower than those of the parabasal layers in normal epithelium and dysplastic lesions, respectively, whereas no difference in CIS was recognized between the two layers. The proportion of PCNA LI in the basal layer of moderate dysplasia was lower than that in the basal layer of severe dysplasia. Conversely, there were no statistical differences between severe dysplasia and CIS in both basal and parabasal layers. In terms of lymphocytic infiltration beneath the dysplasia, there was a close relationship between the degree of lymphocytic infiltration and the PCNA index of the basal and parabasal layers. CONCLUSIONS: PCNA expression may be a useful marker to reflect the biologic characteristics of esophageal dysplasia, suggesting that a high grade of dysplasia is as serious a lesion as esophageal carcinoma.

Biomarkers↗

[Biological characteristics and prognosis of supraglottic carcinoma--a multivariate correlation analysis of prognosis].

The biological characteristics of supraglottic carcinoma was studied with special reference to the correlations of various biological factors with the prognosis of the lesion. The study included 100 cases of supraglottic carcinoma treated by total laryngectomy in the First Hospital of China Medical University in the period from 1975 to 1978, and 7 factors including histopathological findings observed in serial sections of the whole larynx, clinical findings, clinical course, etc. These factors were statistically analyzed by multiple correlation analysis using the theory of quantification I to determine the relations of these factors to the prognosis, as well as their participations in post operative course. 1. Twenty-seven cases died within 5 years after surgery, and 4 cases could not be followed up. 3 and 5-year survival rates were 79.5% and 72.2%, respectively, as calculated in accordance with the UICC General Rule. 2. Histopathologically 5-year survival rate was 10.0% in cases with poorly differentiated carcinoma, 78.0% in cases with moderately differentiated type, and 83.5% in cases with well-differentiated type. It was remarkably lower in poorly differentiated carcinoma than that in moderately or well-differentiated carcinoma. 3. In cases having dense lymphocyte infiltration associated with lymph follicles in peripheral region of tumor, 5-year survival rate was higher (90.4%) than in the other cases. 4. It was found that, as tumor size increased, 5-year survival rate decreased and the risk of lymph node involvement increased in the neck region. 5. 5-year survival rate was lower (48.5%) in cases with lesion infiltrating the surrounding tissues than in cases with other growth patterns. 6. Multiple correlation coefficient between prognosis and the 7 factors analyzed was 0.766. The important factors were the degree of differentiation (0.735), the degree of lymphocyte infiltration (0.260), the size of primary tumor (0.215), the growth pattern of tumor (0.141) and neck metastasis (0.028).

Carcinoma, Squamous Cell↗

Antigenic phenotype and biological characteristics of two distinct sublines derived from a small cell lung carcinoma cell line.

Two sublines, SCLC-MOA1 (MOA1) and SCLC-MOA2 (MOA2), were established from the SCLC-MO cell line, which was originally derived from an oat cell type of small cell lung carcinoma (SCLC). SCLC-MO showed typical culture morphology of SCLC, growing as tightly packed floating aggregates, while both MOA1 and MOA2 grew as a monolayer. MOA2 showed markedly shorter culture doubling time and higher colony forming efficiency than SCLC-MO and MOA1. When transplanted into nude mice, both SCLC-MO and MOA1 showed intermediate cell type histology, while MOA2 showed a picture of large cell carcinoma as non-SCLC. As for biomarkers, SCLC-MO showed a transitional state between the classic and the variant types, while MOA1 was the variant type. In contrast, MOA2 lost the biomarker characteristic of SCLC, showing rather non-SCLC type. SCLC-MO expressed NE-150 neuroendocrine antigen, but lacked PE-35 panepithelial antigen which is generally present on SCLC. It lacked also OE-130 epithelial antigen which is generally absent from SCLC. Thus, the phenotype was NE-150+/PE-35-/OE-130-, which was different from the major phenotype of SCLC, NE-150+/PE-35+/OE-130-. MOA1 was weakly positive for PE-35, showing NE-150+/PE-35 +/- /OE-130-, while MOA2 was positive for OE-130, but lost NE-150, i.e., NE-150-/PE-35+/OE-130+, showing a non-SCLC phenotype. Thus, a good concordance was observed between the antigenic phenotype and the biological characteristics of these SCLC lines. The results altogether suggested that a part of large cell carcinoma in the tumor of the patient may be derived from SCLC. Karyotype analysis showed that there were several marker chromosomes including deletion of chromosome 3p shared by these three cell lines, supporting the belief that MOA1 and MOA2 originated from SCLC-MO. Southern blot analysis showed the amplification of the L-myc related gene, probably rearranged L-myc, in the primary SCLC tumor as well as in SCLC-MO and MOA1. Northern blot analysis showed the 2.2-kilobase transcripts hybridized with a L-myc probe were observed in SCLC-MO and MOA1, but not in MOA2. In contrast, the c-myc transcript was detected only in MOA2. The activity of the myc gene family may contribute to certain biological characteristics of SCLC.

Animals↗

[Comparison and discrimination of the biological characteristics between West Nile virus and Japanese encephalitis virus].

BACKGROUND: To compare the biological characteristics of West Nile virus (WNV) and Japanese encephalitis virus (JEV), including cells sensitivity, pathogenicity, viral morphology, as well as the results of immunological and molecular biological detection. METHODS: Cytopathic effect (CPE) and pathogenicity were observed in C6/36 cells and in suckling mice inoculated intracerebrally with the WNV or JEV, respectively. The sliced tissue samples for electron microscopic examination were prepared for the morphologic observation of the viruses. Serum antibody to WNV or JEV was detected using indirect immunofluorescence assay (IFA), and the viral RNA was analyzed by RT-PCR method. RESULTS: WNV or JEV-caused CPE was characterized by cell fusion and cell shedding, respectively. There was no significant difference in the pathogenicity to suckling mice between WNV and JEV. The morphologic observation showed that the shape and size of the two virions were similar. WNV and JEV were found to have antigenic cross-reactivity. The viral RNA could be detected from both WNV and JEV samples with universal primer set, but only nucleoside fragments of corresponding virus could be amplified when specific primers were used. CONCLUSION: CPE in C6/36 cell and detection of the viral RNA should be useful in discrimination of WNV and JEV, and simultaneously examining the titers of serum antibodies against WNV and JEV may be helpful to diagnosis of infection with these agents.

Animals↗

Biological characteristics of human bone marrow mesenchymal stem cell cultured in vitro.

Some biological characteristics of human bone marrow mesenchymal stem cells (MSCs) cultured in vitro were observed. hMSCs were isolated from bone marrow and purified by density gradient centrifugation method, and then cultured in vitro. The proliferation and growth characteristics of hMSCs were observed in primary and passage culture. MSCs of passage 3 were examined for the purify by positive rate of CD29 and CD44 through flow cytometry. Human bone marrow MSCs showed active proliferation capacity in vitro. The purify of MSCs separated by our method was higher than 90%. It was concluded that hMSCs have been successfully cultured and expanded effectively. It provided a foundation for further investigation and application of MSCs.

Bone Marrow Cells↗