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[Research of the RNA-coliphages, in comparison with usual microbial and chemical indexes of biological pollution, for hygienic and sanitary evaluations of coast-waters (author's transl)].

Hygienic significance of the usual microbial (E. coli, Enterococci, Clostridia) and chemical (COD, NH3, NO2) indexes of sea-water biological pollution was investigated, in comparison with RNA-coliphages assay. E. coli was confirmed as an easily measurable and significant index of biological pollution (at least for routinary investigations), while the other microbial and chemical parameters do not significantly increase the hygienic selectivity of the E. coli assay. RNA-coliphages assay, on the contrary, is able to increase the hygienic selectivity of sanitary investigations, particularly in lowly polluted coast-water. This behaviour of RNA-coliphages is in accordance with their great persistance in sea-water, due to their survival-time, closely comparable with human viruses. RNA-coliphages assay is therefore proposed as a simple and useful index of "viral pollution" for a complete hygienic evaluation of sea-water environment in addition to routinary E. coli assay.

Coliphages↗
PubMed1979

[Degree of sexual maturation as an index of biological age].

Attempt was made to establish some characteristics of sexual maturation, depending upon chronologic and biologic age. A total of 1277 girls from 8 to 17 years of age in the city of Sofia are included in the study. There were no cases of precocious of considerably delayed pubertal development. Essential differences were found in the body dimensions, in connection with the increase in the degree of sexual maturation in one and the same chronologic age. The importance of biologic age for the individual approach to teen-agers girls and boys is emphasized.

Adolescent↗
PubMed2026

Occurrence and Characterization of Graft-Transmissible Pathogens of Citrus in Orchards and Urban Citrus in Chile with a Focus on the Apscaviroid nanocitri.

Apscaviroid nanocitri (citrus dwarfing viroid, CDVd) is a graft-transmissible pathogen that frequently coexists with other citrus viroids and affects tree vigor. This study evaluated the occurrence of citrus viroids in small growers and commercial orchards in Chile and characterized CDVd strains obtained from urban Citrus spp. trees, with unknown propagation history following the discontinuation of the national citrus certification program. A total of 301 samples from five citrus-producing regions were analyzed, revealing that CDVd is widely distributed and commonly associated with Hostuviroid impedihumuli (hop stunt viroid, HSVd). Single infections were the most frequent (41%), followed by double (7.3%) and triple infections (3.0%), indicating that mixed infections are common. CDVd strains from urban trees were characterized using biological indexing on 'Etrog' citron Arizona 861-S-1 indicator plants combined with RT-PCR detection and phylogenetic analysis. Symptom development and pathogen detection were evaluated at 6 and 18 months post-inoculation. All graft-inoculated plants developed symptoms consistent with viroid infection, whereas control plants remained asymptomatic. CDVd was consistently detected at 18 months but not at earlier stages, suggesting delayed systemic accumulation. Although Closterovirus tristezae (citrus tristeza virus, CTV) was present in the source plants, it was not detected in indicator plants at either time point, possibly associated with the higher temperatures required for viroid symptom development during bioindexing. The frequent occurrence of mixed infections highlights the epidemiological relevance of viroid interactions and supports the need for reinstatement and strengthening of the national citrus certification program.

Apscaviroid nanocitri↗
PubMed1978

Clinical appearance of dental fluorosis in permanent teeth in relation to histologic changes.

Based on studies in Northern Tanzania a new classification system of dental fluorosis is proposed. The classification system includes 10 scores designed to characterize the degree of dental fluorosis affecting buccal/lingual and occlusal surfaces. With aid of polarized and ordinary light microscopy the histologic features behind the individual scores are described. The macroscopic appearance of increasing degrees of dental fluorosis were well correlated to the degree of subsurface porosity. Above a certain level of subsurface hypomineralization various degrees of loss of surface enamel occurred, presumably as a result of posteruptively acquired injuries. Application of the new classification system to samples of children born in areas with 3.5, 6.0 and 21.0 parts/10(6) F- in the water supplies revealed that the distribution of dental fluorosis within the individual followed the same pattern irrespective of fluoride concentration in the water. While the classical Dean index was unable to distinguish between dental fluorosis in the 6.0 and the 21.0 parts/10(6) area it was possible with the new system to disclose that particularly the posterior teeth were significantly more affected in the latter area. Comparisons of degree of dental fluorosis with available measurements of enamel thickness proved that the within-tooth as well as within-dentition variations are determined by enamel thickness rather than length of exposure to body fluids. The limitations of the Dean index are discussed with special attention to its validity as a biological index in relation to current efforts to determine the minimal toxic effect of fluoride on the dental hard tissues.

Adolescent↗
PubMed1976

[Methodological problems in the determination of biological age].

It is reported on a new method of the establishment of the biological age. The test battery designed comprises 12 parameters, from which a so-called biological index can be calculated which on its part serves as basis for the establishment of biological age. The realisability of the methods is demonstrated by examinations carried out on 340 healthy persons. The method developed for the geriatric practice is regarded as supplementation of the general medical examination and for the clarification of certain, above all gerontologically orientated questions.

Aging↗
PubMed1978

Red-cell pyrimidine 5'-nucleotidase and lead poisoning.

In an effort to determine its value as a biological index of lead poisoning, we investigated the red-cell pyrimidine 5'-nucleotidase (Py5N) activity, along with the classical parameters, in 22 subjects with varying degrees of lead intoxication. In all cases, the red-cell Py5N activity was found to be decreased, even when most of the other biological tests of lead intoxication remained negative. Below the level of 150 microgram of lead per 100 ml of blood, the magnitude of the red-cell Py5N decrease was roughly proportional to the level of lead in peripheral blood. We conclude that red-cell Py5N is a convenient, reliable and sensitive index of lead exposure.

Clinical Enzyme Tests↗
PubMed1975

Lead. Possible toxicity in urban vs rural rats.

The degree of lead poisoning in wild rats from two environments has been studied. Wild rats captured in an urban area had markedly elevated tissue lead compared with values in rural rats. This elevation may have been caused by differences in factors affecting absorption of ingested lead or an elevated respiratory exposure to airborne lead, or both, and lead in precipitated dust. Changes in several biologic indexes (depression of delta-amino levulinic acid dehydratase in kidney and red blood cells, presence of renal intranuclear inclusion bodies, and increased kidney weight) confirmed lead-poisoning in urban rats.

Adult↗
PubMed1979

Thyroid status in fifty patients with alcoholic cirrhosis.

Because the liver is of considerable importance in metabolism of thyroid hormones, plasma levels of thyroxine (T4), triiodotyronine (T3) with their unbound fractions (FT4 and FT3), reverse T3 (rT3)--an inactive isomer of T3-tyrotropin (TSH) and TSH response to thyrotropin releasing hormone (TRH; 250 micrograms i.V.) were determined by radioimmunoassays in 50 clinically euthyroid patients with alcoholic cirrhosis. T4 mean concentration (7.3 micrograms/dl) did not differ from normal values but T3 was decreased (101 vs 154 ng/dl; p less than 0.001) and was correlated with the degree of liver damage appreciated by a clinico-biological index. FT4 was elevated in patients (17.1 vs 13.1 pg/ml; p less than 0.02) although FT3 was slightly decreased (3.4 vs 4.5 pg/ml; p less than 0.10) with an increased FT4: FT3 ratio (7.0 vs 3.0; p less than 0.02). rT3 was elevated (592 vs 206 ng/100 ml; p less than 0.001) and correlated with FT4/FT3: rT3/T3 ratio (p less than 0.01) and with the severity of the cirrhosis. Basal TSH levels (3.3 microU/ml) and TSH responsiveness to TRH was normal though very scattered, and independant from T3 and T4 values. It may be concluded that: 1. euthyroidy in cirrhosis assessed by a normal responsiveness to TRH, results from a compensatory increase in FT4. 2. The low T3 and FT3 levels may proceed from an impairment of peripheral T4 in to T3 conversion with a deviation pathway towards rT3. 3. T3 and rT3 levels provide valuable index of the severity of the cirrhosis.

Humans↗
PubMed1977

[Antiviral activity in the serum of patients with acute myelocytic leukemia: prognostic significance. Preliminary report].

In view of suggestions that acute myeloblastic leukemia (AML) may be of viral etiology, sera of 31 patients suffering from AML were investigated for antiviral activity. Fowl plague virus (FPV), vesicular stomatitis virus (VSV), BT 20 mammary carcinoma cells and chicken embryo fibroblasts (CEF) were used as assay systems. In the FPV-BT20 system, 19 of 20 patients whose blood sample was taken when they were in complete remission showed antiviral activity in their sera. These patients stayed in complete remission for at least three months after the blood sample was taken. In the sera of 11 patients no antiviral activity could be found with the FPV-BT20 assay system. 3 of the 11 were in relapse, 5 had a relapse within 3 months and 3 stayed in remission more than 3 months after the blood sample was taken. In the FPV-CEF and in the VSV-BT20 system antiviral activity was also found. The activity in the FPV-CEF system corresponded well with the FPV-BT20 assay and the disease status, whereas the activity detected by the VSV-BT20 system did not. The nature of the antiviral activities in the sera of AML patients against FPV and VSV is not yet clear. Interferon and specific antiviral antibodies can probably be ruled out. The antiviral activity against FPV appears to be a biological index of the activity of the disease and might eventually be used to determine intensity and length of treatment.

Animals↗
PubMed1977

[Chromium exposure biological indices and clinical findings in chromium plating industry (author's transl)].

According to the investigations carried out on workers of two chromium plating plants, the authors believe that chromium urinary excretion allows to determine the degree of its acute absorption. Moreover, the renal clearance of diffusible chromium allows the evaluation of chromium body burden and is related to the duration as well as to the severity of exposure. This interpretation is supported by the relation between the exposure biological indexes and the clinical and instrumental investigations which make possible the evaluation of lesions caused by chromium exposure, mostly concerning the respiratory system.

Body Burden↗
PubMed2026

Adolescent depression as a systemic multimorbidity catalyst: integrated genetic and metabolic pathway analysis.

BACKGROUND: Although adolescent depression has been linked to individual chronic conditions, its broader role in shaping multimorbidity risk remains understudied. METHODS: A total of 87,562 UK Biobank participants were included, of whom 18,851 had documented adolescent depression. Cox proportional hazards models were applied to evaluate associations between adolescent depression and 24 chronic diseases, followed by stratified analyses by sex and age. Two-sample Mendelian randomization (MR) was then conducted to infer causality for diseases showing significant associations. Genomic colocalization analyses were performed using relevant GWAS data to identify shared causal variants. Mediation analyses were performed to detect possible mediating factors, including the frailty index, KDM biological age acceleration, allostatic load and 30 circulating biomarkers. RESULTS: Adolescent depression was associated with elevated risk for 12 chronic diseases, with strongest associations for hypothyroidism (HR = 1.29 [1.18-1.42]), diabetes (HR = 1.25 [1.13-1.38]) and chronic obstructive pulmonary disease (COPD) (HR = 1.74 [1.50-2.01]). Risks were notably higher among females and younger adults. MR confirmed likely causal relationships for hypothyroidism (OR = 1.45 [1.03-2.05]), diabetes (OR = 1.01 [1.01-1.02]) and COPD (OR = 1.04 [1.02-1.06]). Genomic colocalization revealed a shared genetic signal at the CDSN/PSORS1C1 locus between adolescent depression and hypothyroidism. Mediation analyses revealed disease-specific pathways: creatinine for hypothyroidism, testosterone for diabetes, KDM biological ageing for COPD and frailty index across all three conditions. CONCLUSIONS: Adolescent depression confers systemic vulnerability through genetic and metabolic mechanisms, with amplified risks in females and individuals aged ≤55 years. These findings support early, integrated interventions to mitigate long-term multimorbidity.

Humans↗
PubMed1976

Concerning the estimation of biological age.

The conditions which must be satisfied by an index of biological age are discussed, and a high correlation with chronological age is shown to be neither a necessary nor a sufficient condition to be satisfied by any such index.

Adult↗
PubMed1976

[Indices of phagocytosis of staphylococci with different biological activity].

An index of completion of phagocytosis was studied for staphylococcus cultures of various biological activity in experiments with surviving polymorphonuclear leukocytes. Among the coagulase-forming staphylococci virulent strains proved to be nonviable in a lesser percentage of cases than the avirulent ones. Coagulase- and mannite-negative cultures proved to be most unstable. Staphylococcus toxin depressed the migration of polymorphonuclear leukocytes to the focus of irritation, inhibited ingestion of the virulent, and, to a lesser degree, of avirulent coagulase-forming staphylococci, but failed to influence the ingestion of coagulase-negative epidermal staphylococci. The influence of staphylotoxin on the phagocytosis completion index was either the minimal or absent entirely.

Animals↗
PubMed1976

[The number of teeth in persons who died within a 5-year period in comparison with survivors].

In reliance on dental records taken in 1965 it was examined whether or not examinees with a higher number of teeth display a better survival rate for the 5 years' periode 1965-1970 than examinees of the same age and sex but with a lower number of teeth; in other words, whether or not, the number of teeth is a suitable index for biological age, at least in the higher age-groups.

Aged↗