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At least 19 recordsLinked to original sources
PubMed1979

IME -- an inhibitor of interferon activity isolated from mouse embryonic tissues. II. Biological characteristics.

The biological properties and mode of action of IME were studied. Extracts of homogenized and lyophilized mouse embryos served as source of IME, which was found to be localized mainly in cells of mouse amnionic membranes and embryonic tissues. Growth of embryos was accompanied by falling activity of the inhibitor. IME activity was manifested only if it acted on cells in established antiviral state, and only in systems with efficient protein synthesis in all stages. IME stimultes cell metabolism. The findings from this study constitute material for further research on factors antagonistic to interferon.

Amnion↗
PubMed1977

[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↗
PubMed1977

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↗
PubMed1977

Biological characteristic of Nigerian strains of West Nile virus in mice and cell cultures.

The biological characteristic in mice and cell cultures of 7 strains of West Nile (WN) virus isolated in Nigeria were studied. The pattern of virus development in most organs of mice infected with two of the seven strains tested was identical, while it varied with the remaining five strains. All 7 strains of WN virus multiplied with a cytopathic effect (CPE) in the four cell cultures examined.

Animals↗
PubMedDate not supplied

[Biological characteristics of various strains of Pseudomonas aeruginosa isolated from human pathological matter].

According to the higher frequency of isolation of bacterial strains belonging to the genus Pseudomonas from various human phatologic materials, in was seemed interesting to study the biological characteristics of these bacteria, which are the most virulent and pathogenic Gram-microorganism. In the present work the results of cultural, biochemical, cytochemical and immunological tests are reported. In vivo tests were also carried out, using rabbits inoculated with whole cells or their products.

Animals↗
PubMed1976

Morphologic and biologic characteristics of adenoid cystic carcinoma cells of the salivary gland.

Adenoid cystic carcinoma cells cultivated in monolayer and sponge matrix culture, or implanted on the chorioallantoic membrane (CAM) of embryonated eggs, were observed morphologically, and the glycosaminoglycan components in the tumor tissue were analyzed. This tumor tissue contained a large amount of glycosaminoglycans, composed of chondroitin 4- and 6-sulfate, heparan sulfate, hyaluronic acid, and a small amount of dermatan sulfate. In monolayer culture spindle cells proliferated vigorously as multilayer, and secreated mucinous material. In sponge matrix culture, the proliferating cells became embedded in the material produced by the cells themselves. A trace of fine fibers stained with orceine was observed in the intercellular material in culture. Histologic sections of the implants grown on CAM showed that the tumor cells arranged in various structures produced a large amount of mucinous material that spread into the stromal area without any contribution from the mesenchymal element. The morphologic and biologic characteristics of these tumor cells are quite similar to those of pleomorphic adenoma.

Adenoma↗
PubMed1979

Qualitative changes in the biologic characteristics of cultured fetal rat keratinizing epidermal cells during the process of malignant transformation after benzo[a]pyrene treatment.

In vitro malignant transformation of fetal rat keratinizing epidermal cells from inbred SD rats after benzo[a]pyrene (BP) treatment was analyzed from various biologic viewpoints. BP treatment directly and indirectly effected changes in cell growth characteristics, i.e., temperature dependence for growth, in vitro keratinization, chromosome structure, and the ability to form colonies on plastic substrate, on 0.57% agar medium layer, and in 0.33% soft agar medium. BP-treated cells at 30 degrees C remained in the premalignant stages and showed shifts in chromosome structure toward the hypodiploid range and parakeratotic changes in their keratinization process. However, the cells failed to form colonies even on a plastic substrate. BP-treated cell lines that adapted to temperatures of 35 and 37.5 degrees C remained in the premalignant stages; however, they acquired the ability to form colonies on plastic substrates during subcultivation. Malignantly transformed colonies appeared in these cell lines. In vitro keratinization processes were classified into nearly normal (diffuse lamellar, focal lamellar, and parakeratotic), intermediate, and atypical subtypes (columnar, spherical, and single-cell type). Cells of atypical keratinization subtypes and some of the intermediate subtypes formed squamous cell carcinomas in syngeneic hosts. Malignantly transformed cells showed shifts in chromosome structure toward the hypotetraploid range and colony formation on the 0.57% agar medium layer. However, they failed to form colonies in 0.33% soft agar medium. With the use of changes in biologic characteristics of the cells as indicators, fetal rat keratinizing epidermal cells in culture were classified into five stages. The appearance of stage III cells seemed to be the first key step in their malignant transformation.

Animals↗
PubMed1976

Use of biological characteristics to type Herpesvirus hominis types 1 and 2 in diagnostic laboratories.

Fifty clinical isolates of Herpesvirus hominis were typed by pock size on chicken embryo chorioallantoic membranes, sensitivity to heparin, and plaque formation on chicken embryo cell cultures. Of 19 isolates that were typed serologically, there was 100% concordance with respect to plaque formation. Pock size was incorrect in one instance and indeterminate in another. Heparin sensitivity was incorrect for one. Of 31 strains that were only biologically characterized, there were four for which heparin sensitivity did not agree with the other two characteristics. Of the three biological tests, the ability to form plaques in chick cell monolayer was the most reliable indicator type.

Animals↗
PubMedDate not supplied

[Antigenic and biological characteristics of influenza A1 viruses isolated in the 1977 pandemic].

Investigations of the antigenic and biological properties of the causative agents of the 1977 influenza epidemic revealed their appurtenance to the old subtype A1 of influenza virus which had disappeared from circulation 20 years ago. A comparative study of A1 viruses isolated in 1947--1956 and A1/77 established closer relationship of the latter to the causative agents of 1949 and 1950 epidemics. The "old" and newly isolated viruses 4ere also closely related biologically. The similarity of influenza A1/77 viruses with the agents of the pandemic cycle of A1 in 1947--1956 is a convincing confirmation of the hypothesis of Francis-Davenport and Smorodintsev-Luzyanina.

Antigens, Viral↗
PubMed2026

Multi-omics-based study on the biological characteristics of kidney renal deficiency and blood stasis in ankylosing spondylitis.

OBJECIVE: To explore the objective biological evidence for the classification and diagnosis of Traditional Chinese Medicine (TCM) syndromes in ankylosing spondylitis (AS) using multiomics analysis. METHODS: Patients with AS were categorized into kidney deficiency and blood stasis syndrome (SX group) and damp-heat stasis syndrome (SR group). Transcriptomic sequencing and quantitative plasma proteomics were performed on patients with AS and healthy volunteers. Multiomics integration was used to characterize the biological basis of AS with renal deficiency and blood stasis syndrome. Specific proteins were validated by quantitative reverse transcription-polymerase chain reaction (RT-qPCR) and enzyme-linked immunosorbent assay (ELISA). RESULTS: Transcriptomic sequencing identified 31 significantly upregulated genes in patients with AS compared to healthy controls. These genes were primarily involved in tumor necrosis factor, interleukin-17, and nuclear factor kappa-B signaling pathways, as well as osteoblast differentiation and various viral infection pathways. Differentially expressed genes, including intercellular adhesion molecule 1 (ICAM1), 6-phosphofructo-2-kinase, cyclin-dependent kinase inhibitor 1A, interleukin 1 receptor antagonist, integrin alpha IIb, and myosin light chain 9 were more upregulated in the SX group than in the SR group. Quantitative proteomics identified 723 differential proteins associated with the disease and 788 differential proteins between the SX and SR groups. Notable proteins such as myeloperoxidase, cluster of differentiation 14, macrophage simulating 1 (MST1), and Ras homolog enriched in brain may serve as characteristic proteins of the SX group. By integrating transcriptomic and proteomic data, 45 associated differential molecules involved in platelet activation, pathogenic intestinal flora infection, glycolysis/gluconeogenesis, and T-cell receptor signaling pathways were identified in patients with AS compared to healthy controls. Additionally, ICAM1, MST1, C-X-C motif chemokine ligand 8 (CXCL8), suppressor of cytokine signaling 3 (SOCS3), and insulin-like growth factor binding protein 1 (IGFBP1) were detected in TCM syndromes by RT-qPCR and ELISA, showing upregulation in AS renal deficiency and blood stasis syndromes, which is consistent with the proteomic and transcriptomic results. CONCLUSIONS: ICAM1, MST1, CXCL8, SOCS3, and IGFBP1 were identified as biomarkers of renal deficiency and blood stasis syndrome in AS. This study provides a biological basis for the differential diagnosis of TCM syndromes in AS, offering new insights into Chinese medicine evidence and more precise Chinese medicine treatments for AS.

Humans↗
PubMed2026

Integrated analysis of plasma metabolomics and proteomics reveals the biological characteristics of damp-heat and stasis-toxin syndrome in colorectal cancer.

OBJECTIVE: To investigate the biological attributes of core syndromes in colorectal cancer, namely, the damp-heat and stasis-toxin syndrome (SRYD). METHODS: Between October 2021 and October 2022, a cohort comprising 40 patients with colorectal cancer (CRC) diagnosed with damp-heat and stasis-toxin syndrome (SRYD group), 40 patients with CRC without this syndrome (non-SRYD group), and 40 healthy controls (Normal group) was recruited at Jiangsu Province Hospital of Chinese Medicine. Untargeted metabolomics analysis was conducted on plasma samples from all 120 participants, while differential protein analysis using four-dimensional data-independent acquisition proteomics was performed on 20 randomly selected samples per group. A combined analysis of proteomics and metabolomics data followed, and the identified potential diagnostic biomarkers were subsequently used to train and validate multiple machine learning models. RESULTS: Proteomic analysis revealed 130 differential proteins in the colorectal cancer with damp-heat and stasis-toxin syndrome (CRC-SRYD) group, enriched in pathways including complement and coagulation cascades, as well as nuclear factor kappa-B (NF-κB) signaling. Metabolomic analysis identified 584 differential metabolites within the same group, showing enrichment in pathways such as primary bile acid biosynthesis, central carbon metabolism in cancer, and glucagon signaling. Integrated pathway analysis indicated heightened activity of the NF-κB signaling pathway in the CRC-SRYD group. A biomarker panel, comprising 6 proteins and 9 metabolites selected through the ReliefF algorithm, was used to construct a diagnostic model with random forest, achieving an accuracy of 93.33%, sensitivity of 80.00%, and specificity of 100%. CONCLUSION: This study systematically elucidates plasma metabolomic and proteomic alterations in patients with CRC, establishing a robust diagnostic model for CRC syndrome (CRC-SRYD). Further investigation is warranted to clarify the underlying molecular mechanisms and biological foundations.

Humans↗
PubMed1977

Immunological and biological characteristics of a new TRF analogue, L-pyroglutamyl-L-histidyl-L-pipecolic acid amide.

The immunological and biological potencies of a new synthetic TRF analogue, L-pyroglutamyl-L-histidyl-L-pipecolic acid amide, were compared with those of TRF. In a radioimmunoassay system for TRF, parallel inhibition curves were obtained with TRF and the analogue, the immunological potency of the latter being approximately 50 per cent of the former. In vitro and in vivo TSH-releasing activities of the analogue were almost equal to those of TRF. As was observed with TRF, the in vitro TSH-releasing effect of the analogue was reduced in the presence of T4, and the analogue was inactivated by incubation with rat serum. The data suggest that the pyrrolidine ring of TRF can be replaced with piperidine ring without significant loss of the biological activity.

Animals↗
PubMed1979

Some biological characteristics of Escherichia coli strains isolated from acute diarrhoeal diseases of infants.

The aim of this study was to evaluate the methods of biological characterization of Escherichia coli strains, in order to use them as screening tests in clinical microbiological laboratories. In two thirds of the 45 E. coli, isolated from acute intestinal infection of infants, different factors of virulence were found. The strains showed prevalently an enterotoxigenic character (66,6%), which was in correlation with the increased permeability (62,2%). Adhesive properties were present in 20% of E. coli independent of their enterotoxigenicity; only 11,1% of the strains had penetrating abilities. The rabbit skin model seems to be accurate and quick for ETEC screening purposes, as is the guinea-pig eye for the EIEC. The mouse intestinal loop has been found sensitive but time-consuming. The infant mouse model is simple and quick, but in this study it has not given optimal results. The Vero cell culture system is simple and easy to perform, but at least for some strains the preparations should be concentrated. The investigation of adhesiveness by haemagglutination is possible to conduct in every small clinical laboratory. Our opinion is, however, that after the isolation of E. coli from different pathological materials, the determination of the antigenic structure of the strains is necessary and later on the additional biological characterization should be performed.

Acute Disease↗
PubMed1975

Metabolism of bovine parathyroid hormone. Immunological and biological characteristics of fragments generated by liver perfusion.

The metabolism of bovine parathyroid hormone (PTH) by the perfused rat liver was studied. Labeled hormone, with or without cold hormone, was infused into the circulating perfusion medium containing various calcium concentrations. Pefusate samples at various time periods after the introduction of PTH into the system were chromatographed on Bio-gel P-10; radioactivity and/or immunoreactivity were measured in eluted fractions. Before the perfusion, all immuno- and radioactivity eluted in a single peak, with an apparent mol wt of 9,500 (peak I). After perfusion for 15 min, two other peaks with approximate mol wt of 7,000 (peak II) and 3,500 (peak III) were discernible. Peak I contained both NH2-terminal and COOH-terminal immunoreactivity and was biologically active at all time periods tested. The relative contribution of NH2-terminal and COOH-terminal immunoreactivity to the total immunoreactivity remained constant in this peak throughout the perfusion. In every respect, peak I had the characteristics of intact hormone. At all times, peak II consisted of only COOH-terminal immunoreactivity and was biologically inactive. At early time periods, peak III contained predominantly NH2-terminal immunoreactivity and was biologically active. With time, the relative contribution of NH2-terminal immunoreactivity decreased strikingly while that of COOH-terminal immunoreactivity increased. The three peaks identified in these experiments were analogous in size, biological activity, and immunological characteristics to those we have previously described for fractionated human hyperparathyroid serum. The rate of metabolism of PTH appeared to be regulated by the calcium concentration in the medium. At a high concentration of calcium (greater than 11 mg/100 ml), PTH metabolism was greatly retarded. At a low concentration of calcium (smaller than 5 mg/100 ml), the rate of metabolism was greatly increased. The physiological significance of our observations on the metabolism of PTH by isolated perfused rat liver is not known. However, since such metabolism results in a biologically active fragment, it is suggested that metabolism of intact hormone may be required before full biological expression is possible.

Animals↗
PubMed2026

Construction of an infectious clone of Spodoptera frugiperda densovirus and its biological characteristics.

Densoviruses are highly pathogenic to their insect hosts and have great potential for biocontrol. Spodoptera frugiperda densovirus (SfDV) was isolated from diseased larvae of Spodoptera frugiperda, while its biological functions remain unclear. Herein, we successfully constructed an infectious clone of SfDV. The S. frugiperda larvae transfected with the infectious clone exhibited anorexia, stunted growth, and reduced activity. Histopathological analysis further showed that the epidermis, fat body and trachea were infected instead of muscle and midgut tissues. Transmission electron microscopy (TEM) revealed that numerous virions of about 22 nm were distributed within both the nucleoplasm and cytoplasm of epidermal cells. Moreover, many virions were also found contained within vesicles in the cytoplasm. The replication kinetics of the rescued SfDV (rSfDV) was similar to that of the parental SfDV. The median lethal dose (LD50) and median lethal time (LT50) values of rSfDV were 6.63 × 107 viral genome copies (vgc), 5.23 d, respectively, which were also comparable to those of the parental SfDV. Taken together, the infectious clone of SfDV provides an important tool for further exploring the genome function, pathogenesis, and interactions with its hosts.

Animals↗
PubMed2026

Thermal biology characteristics of the Caspian whipsnake (Dolichophis caspius, Gmelin, 1789) under natural and laboratory conditions.

Reptiles rely on behavioural thermoregulation to maintain optimal body temperature (Tb), essential for many physiological functions. However, thermal biology remains poorly studied in many snake species, including the Caspian whipsnake (Dolichophis caspius, Gmelin, 1789). This study examined the thermal biology of the Caspian whipsnake under natural and laboratory conditions. In the field, we investigated the influence of sex, age category, season, time of day, air temperature, detection status, feeding status, and shedding phase on Tb. Under controlled conditions, we assessed preferred Tb variation and its relationship to active thermoregulation. In the field, Tb was significantly affected by sex, season, time of day, air temperature, feeding status, and shedding phase, but not age category, body size or detection status. Males had lower Tb than females and snakes with food in their stomachs exhibited higher Tb. Tb increased from March to June and from morning to afternoon, and air temperature had a positive effect on Tb. In the laboratory, mean Tb (24.5 ± 4.9 °C) was lower than in the field (26.9 ± 5.2 °C) and was significantly associated with body posture and terrarium part, indicating active behavioural thermoregulation. In the laboratory, males had lower Tb than females, and juveniles had lower Tb than adults. The lower thermal preference suggests a cooler thermal niche than many colubrids, potentially increasing their susceptibility to climate warming. However, the broad Tb variation and behavioural thermoregulation indicate some flexibility in responding to environmental changes. These findings highlight the role of behavioural thermoregulation in snake thermal responses to environmental variation.

Behavioural thermoregulation↗