scholarly journals Environmental and social factors impacting on epidemic and endemic tuberculosis: a modelling analysis

2018 ◽  
Vol 5 (1) ◽  
pp. 170726 ◽  
Author(s):  
Chacha M. Issarow ◽  
Nicola Mulder ◽  
Robin Wood
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Social Factors ◽  
Environmental Conditions ◽  
Population Level ◽  
Transmission Probability ◽  
Infectious Dose ◽  
Air Volume ◽  
Effective Contact ◽  
Modelling Analysis ◽  
The Mean

Tuberculosis (TB) transmission results from the interaction between infective sources and susceptible individuals within enabling socio-environmental conditions. As TB is an airborne pathogen, the transmission probability is determined by the volume of air inhaled from an infected source and the concentration of Mycobacterium tuberculosis containing respirable particles (doses) per volume of air. In this study, we model the contributions of infectious dose production, prevalence of infectious cases and daily rebreathed air volume (RAV) for defining the boundary conditions necessary to sustain endemic TB transmission at the population level. Results suggest that in areas with high RAV (range 300–1000 l d −1 ), such as prisons, TB transmission is contributed by both super-spreaders (exhaling ≥10 infectious doses hr −1 ) and lower infectivity individuals (exhaling less than 10 infectious doses hr −1 ). In settings with a low quantity of RAV (less than 100 l d −1 ), TB transmission occurs only from super-spreaders. Point-source epidemics occur in low rebreathed environments when super-spreaders infect a number of susceptibles but subsequent transmission is limited by the mean infectivity of secondary cases. By contrast, endemic TB occurs in poor socio-environmental conditions where mean infectivity cases are able to maintain a sufficiently high effective contact number.

Determination some Immunological Aspects in Pulmonary Tuberculosis Patients in Qadisiyah Province

2018 ◽  
Vol 9 (2) ◽  
Author(s):  
Syoof Khowman Alramahy ◽  
Akram Hadi Hamza
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Pulmonary Tuberculosis ◽  
Statistical Difference ◽  
Positive Culture ◽  
Control Group ◽  
Tuberculosis Patients ◽  
Significant Difference ◽  
Lowenstein Jensen ◽  
The Mean ◽  
Igg Level

This study was carried out to study of some immunological aspects among the pulmonary Tuberculosis patients infected with causative agent, Mycobacterium tuberculosis. A Total of 200 sputum samples were collected from patients attending the consultant Clinic for Chest and Respiratory disease center, Diwaniya. Control group (No=15) also included. According to acid fast stain of sputum, the patients were classified as positive (No=91,45.5%) and negative (No=109,54.5, Lowenstein Jensen medium used for the cultivation of samples, on which 70% of sputum samples where positive culture for this microorganism. The grown microorganism were identified as M. tuberculosis, based on positive A.F.B, Niacin producers ,negative for catlase at 68c. The mean IgG level was l184.053±76.684 mg/100 ml in tuberculosis group compared with 1016.533 ± 44.882 mg/100ml in control group, rendering the statistical difference significant. For IgA and IgM levels, they were at mean of 315.880±38.552 mg/100 ml and 119.527±8.464 mg/100 ml in control group compared with 396.358±38.776 mg/100 ml and 134.207±11.696 mg/100 ml in patients group respectively with significant difference

COLONY OF THE FUNGUS Aspergillus oryzae AND SELF-AFFINE FRACTAL GEOMETRY OF GROWTH FRONTS

Fractals ◽  
1993 ◽  
Vol 01 (01) ◽  
pp. 11-19 ◽  
Author(s):  
SHU MATSUURA ◽  
SASUKE MIYAZIMA
Keyword(s):  
Aspergillus Oryzae ◽  
Environmental Conditions ◽  
Fractal Geometry ◽  
Nutrient Concentration ◽  
Incubation Temperature ◽  
Characteristic Exponent ◽  
Growth Front ◽  
Favorable Condition ◽  
The Self ◽  
The Mean

A variety of colony shapes of the fungus Aspergillus oryzae under varying environmental conditions such as the nutrient concentration, medium stiffness and incubation temperature are obtained, ranging from a homogeneous Eden-like to a ramified DLA-like pattern. The roughness σ(l, h) of the growth front of the band-shaped colony, where h is the mean front height within l of the horizontal range, satisfies the self-affine fractal relation under favorable environmental conditions. In the most favorable condition of our experiments, its characteristic exponent is found to be a little larger than that of the 2-dimensional Eden model.

Étude du développement hétéroblastique chez quelques espèces du genre Medicago

1983 ◽  
Vol 61 (8) ◽  
pp. 2212-2223 ◽  
Author(s):  
Catherine Damerval
Keyword(s):  
Environmental Conditions ◽  
Mean Value ◽  
Annual Species ◽  
The Mean ◽  
Shape Changes

Seven foliar types were defined for the first leaf in the heteroblastic development of seven annual species of Medicago L. Among the species, M. aculeata and M. murex have a typical foliar form. There is no relation between the first leaf and the succeeding trifoliolate one. The shape changes of the middle foliole of the trifoliolate leaves during the development allowed to establish a foliar sequence whose mean length was used to suggest an evolutive hierarchy among the taxa. Five quantitative variables were analysed on the first and on the sixth leaf for stability according to environmental conditions; the two stable variables (L/l and L/Pl) have a best discriminant value for the first leaf than for the sixth one. However, intraspecific heterogeneity is high in both cases. A relation between the flowering precocity and the mean value of one of the sixth leaf's variables (that is, the ratio of the length to the width of the foliole limb) was demonstrated in four species only. The heteroblastic development not only allows to establish a relation between foliar stage and physiologic age, but it itself constitutes a very good taxonomic and systematic criterium; it allowed to identify the seven species studied.

scholarly journals Determinants of SARS-CoV-2 transmission to guide vaccination strategy in a city

2020 ◽  
Author(s):  
Sarah C. Brüningk ◽  
Juliane Klatt ◽  
Madlen Stange ◽  
Alfredo Mari ◽  
Myrta Brunner ◽  
...  
Keyword(s):  
Vaccination Strategy ◽  
Population Level ◽  
Data Sets ◽  
Epidemic Dynamics ◽  
Modelling Analysis ◽  
City Population ◽  
Senior Population ◽  
Spatio Temporal ◽  
Socioeconomic Data ◽  
The City

Transmission chains within cities provide an important contribution to case burden and economic impact during the ongoing COVID-19 pandemic, and should be a major focus for preventive measures to achieve containment. Here, at very high spatio-temporal resolution, we analysed determinants of SARS-CoV-2 transmission in a medium-sized European city. We combined detailed epidemiological, mobility, and socioeconomic data-sets with whole genome sequencing during the first SARS-CoV-2 wave. Both phylogenetic clustering and compartmental modelling analysis were performed based on the dominating viral variant (B.1-C15324T; 60% of all cases). Here we show that transmissions on the city population level are driven by the socioeconomically weaker and highly mobile groups. Simulated vaccination scenarios showed that vaccination of a third of the population at 90% efficacy prioritising the latter groups would induce a stronger preventive effect compared to vaccinating exclusively senior population groups first. Our analysis accounts for both social interaction and mobility on the basis of molecularly related cases, thereby providing high confidence estimates of the underlying epidemic dynamics that may readily be translatable to other municipal areas.

scholarly journals Evaluation of Genetic behavior of Sunflower (Helianthus annuus L.) As Effect by Planting Dates

2019 ◽  
Vol 9 (1) ◽  
pp. 150-155
Author(s):  
Abdullah F. Serheed ◽  
Haider T. Hussein
Keyword(s):  
Helianthus Annuus ◽  
Correlation Coefficient ◽  
Environmental Conditions ◽  
Genetic Variance ◽  
Planting Dates ◽  
Environmental Variance ◽  
Growing Seasons ◽  
The Mean ◽  
Phenotypic Variations ◽  
Coefficient Stability

Afield experiment was carried out during the spring and autumn seasons of 2016 and 2017 in AL- Musaib city / 40 km north of Babylon Provence. Two hybrids of sunflower( shamus, French hybrid (Euroflor) were used to evaluate the performance of the two cultivars at both growing seasons as well as knowledge of genetic behavior by studying the genetic and phenotypic variations, heritability percent, genetic and phenotypic coefficient, stability and persistence of the two cultivars .The results showed significant differences of the studied traits, as the genetic genotype (Shamus) most of the characteristics, especially in yield for two seasons.The genetic variance was higher than the environmental variance for the two seasons indicating that the two cultivars followed the same behavior. The heritability percent the dominant sense was high for most of the traits. The genetic and phenotypic variations between the mean and the high were different for the two seasons, the correlation coefficient was significant, for both cultivars, indicating the appropriateness of the two genotypes for the country's environmental conditions.

scholarly journals The sources of sex differences in aging in annual fishes

2020 ◽  
Author(s):  
Martin Reichard ◽  
Radim Blažek ◽  
Jakub Žák ◽  
Petr Kačer ◽  
Oldřich Tomášek ◽  
...  
Keyword(s):  
Sex Differences ◽  
Social Environment ◽  
Social Factors ◽  
Environmental Conditions ◽  
Natural Populations ◽  
Experimental Results ◽  
Survival Difference ◽  
Captive Populations ◽  
Baseline Mortality ◽  
In The Wild

AbstractSex differences in lifespan and aging are widespread among animals, with males usually the shorter-lived sex. Despite extensive research interest, it is unclear how lifespan differences between the sexes are modulated by genetic, environmental and social factors. We combined comparative data from natural populations of annual killifishes with experimental results on replicated captive populations, showing that females consistently outlived males in the wild. This sex-specific survival difference persisted in social environment only in two most aggressive species, and ceased completely when social and physical contacts were prevented. Demographically, neither an earlier start nor faster rate of aging accounted for shorter male lifespans, but increased baseline mortality and the lack of mortality deceleration in the oldest age shortened male lifespan. The sexes did not differ in any measure of functional aging we recorded. Overall, we demonstrate that sex differences in lifespan and aging may be ameliorated by modulating social and environmental conditions.

scholarly journals Mycobacterium of tuberculosis with defective cell wall, determined in the brain of the biological model with spongional changes

2019 ◽  
Vol 23 (1) ◽  
pp. 12-19
Author(s):  
O.P. Lysenko ◽  
V.V. Vlasenko ◽  
H.K. Palii ◽  
I.H. Vlasenko ◽  
O.A. Nazarchuk
Keyword(s):  
Central Nervous System ◽  
Cell Wall ◽  
Nervous System ◽  
Mycobacterium Tuberculosis ◽  
Brain Damage ◽  
Molecular Genetic Study ◽  
Central Nervous System Damage ◽  
Infectious Dose ◽  
Microbiological Methods ◽  
The Brain

Mycobacterium tuberculosis is endowed with resistance to adverse factors and rapidly forms drug resistance. The aim is to study of the connection of tuberculosis infection and the development of brain damage with signs of spongymorphic changes. There were investigated canned 10% formalin fragments of the brain of 2 goats with signs of central nervous system damage by histological, microbiological methods. For microbiological examination, 3–5 years brain samples after were sowed on the MycСel DW nutrient medium with a growth stimulator. The molecular genetic study was performed using a polymerase chain reaction on a Molecular Imager GelDoc TM XR + (BioRad) device. The polypeptide profile was studied electrophoretically. In the goats, who died with symptoms of central nervous system damage, spongiform changes were detected in the brain. In the brain samples, DNA and mycobacterium tuberculosis with a defective cell wall have been detected, accumulation of mycobacterial antigens has been observed in the cells of the brain and in the intercellular space. Despite the fact that brain samples were in 10% formalin for 1 month, 3 years and 5 years, in all cases mycobacterium tuberculosis with a defective cell wall was isolated. Their viability was comparable to the infectiousness of prions. The isolation of mycobacterium tuberculosis with a defective cell wall from the brain did not differ in morphology and polypeptide composition from isolates from tuberculin, FLK-BLV, lymph nodes of cows, patients with tuberculosis. This indicates a high probability that mycobacterial infection, depending on the infectious dose, the characteristics of the strain and host genome, as well as the state of the immune system, can cause oncogenic action, cause active tuberculosis, brain damage, and the cardiovascular system.

The breeding behaviour of the endangered regent honeyeater, Xanthomyza phrygia, near Armidale, New South Wales

1998 ◽  
Vol 46 (2) ◽  
pp. 153 ◽  
Author(s):  
Damon L. Oliver
Keyword(s):  
New South ◽  
New South Wales ◽  
Population Level ◽  
Similar Rate ◽  
Nest Construction ◽  
Aggressive Interactions ◽  
Breeding Behaviour ◽  
South Wales ◽  
The Mean ◽  
Breeding Seasons

The regent honeyea ter, Xanthomyza phrygia, is an endangered woodland bird whose range and population size have decreased in the last thirty years. Suggested reasons for this decline include abnormal breeding behaviour, poor reproductive output, and excessive inter- and intra-specific aggression. This study investigated the breeding behaviour and aggressive interactions of regent honeyeaters during the nest construction, incubation, nestling, and fledgling stages in two consecutive breeding seasons in the Bundarra–Barraba region near Armidale, New South Wales. The female was entirely responsible for nest construction and incubation, which is typical of many honeyeaters. Both parents fed the nestlings, and at a similar rate, although only the female brooded chicks on the nest. Both parents fed the fledglings. The mean frequency at which nestlings (23 times per hour) and fledglings (29 times per hour) were fed is the highest published rate of any non-cooperative honeyeater. Breeding males were involved in significantly more aggressive interactions with conspecifics and other nectarivores than were females, although the overall percentage of day-time spent in aggression for both sexes was low (2.5%). It appears that abnormal breeding behaviour, poor reproductive effort, or excessive aggression are not experienced by this species in northern New South Wales, and that other factors are likely to be responsible for its current low population level.

scholarly journals Characterization of rifampicin-resistant Mycobacterium tuberculosis in Taiwan

2003 ◽  
Vol 52 (3) ◽  
pp. 239-245 ◽  
Author(s):  
Hsing-Yu Hwang ◽  
Chung-Yu Chang ◽  
Lin-Li Chang ◽  
Shui-Feng Chang ◽  
Ya-Hui Chang ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Core Region ◽  
Banding Patterns ◽  
The Core ◽  
Resistant Tuberculosis ◽  
Proportion Method ◽  
The Mean ◽  
Novel Alleles ◽  
The Relationship

Sixty-three rifampicin-resistant (Rifr) isolates of Mycobacterium tuberculosis from Kaohsiung, Taiwan, were analysed for mutations in the core region (69 bp, codons 511–533) of the rpoB gene. Some 84.1 % (53/63) of the resistant isolates showed mutations in this region, especially in codons 531 (41.5 %), 526 (18.9 %), 516 (15.1 %) and 533 (7.5 %). Five novel alleles of a total of 16 different types of mutations were identified in Rifr isolates. Ten Rifr isolates (15.9 %) exhibited no mutations in the core region of rpoB. Also, they did not show mutations in another 365 bp fragment (codons 99–220) of rpoB. The agar proportion method was used to determine the relationship between the degree of rifampicin resistance and alterations in the core region of rpoB. The results revealed that the mean MIC was 92.38 μg ml−1 for the 53 isolates with a mutation in the core region, whereas the mean MIC of the other 10 isolates without mutations was only 24.8 μg ml−1. This indicates that the isolates with mutations in the core region had higher levels of resistance than those without mutations in this region. IS6110 restriction fragment length polymorphism (RFLP) was used for typing of 55 Rifr M. tuberculosis isolates. Isolates contained two to 19 copies of IS6110, with sizes ranging from 600 to 16 000 bp. The majority (85 %) contained six to 16 copies. No strains lacking IS6110 were found. A total of 54 of 55 RFLP types were defined at the 90 % similarity level. The observation of varied IS6110-associated banding patterns indicates that an outbreak of drug-resistant tuberculosis did not occur in this area.

scholarly journals Clinical and radiographic features of HIV-related pulmonary tuberculosis according to the level of immunosuppression

2007 ◽  
Vol 40 (6) ◽  
pp. 622-626 ◽  
Author(s):  
Guilherme Freire Garcia ◽  
Alexandre Sampaio Moura ◽  
Cid Sérgio Ferreira ◽  
Manoel Otávio da Costa Rocha
Keyword(s):  
Weight Loss ◽  
Mycobacterium Tuberculosis ◽  
Pulmonary Tuberculosis ◽  
Bronchoalveolar Lavage ◽  
Lymphocyte Count ◽  
Radiographic Features ◽  
Cd4 Lymphocyte Count ◽  
The Mean ◽  
Cd4 Lymphocyte ◽  
Primary Pattern

Medical charts and radiographs from 38 HIV-infected patients with positive cultures for Mycobacterium tuberculosis from sputum or bronchoalveolar lavage were reviewed in order to compare the clinical, radiographic, and sputum bacilloscopy characteristics of HIV-infected patients with pulmonary tuberculosis according to CD4+ lymphocyte count (CD4). The mean age of the patients was 32 years and 76% were male. The median CD4 was 106 cells/mm³ and 71% had CD4 < 200 cells/mm³. Sputum bacilloscopy was positive in 45% of the patients. Patients with CD4 < 200 cells/mm³ showed significantly less post-primary pattern (7% vs. 63%; p = 0.02) and more frequently reported weight loss (p = 0.04). Although not statistically significant, patients with lower CD4 showed lower positivity of sputum bacilloscopy (37% vs. 64%; p = 0.18). HIV-infected patients with culture-confirmed pulmonary tuberculosis had a high proportion of non-post-primary pattern in thoracic radiographs. Patients with CD4 lower than 200 cells/mm³ showed post-primary patterns less frequently and reported weight loss more frequently.

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