biological factors
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Viruses ◽  
2022 ◽  
Vol 14 (1) ◽  
pp. 131
Author(s):  
Peter Hodoameda ◽  
Linus Addae ◽  
Rollie J. Clem

The mechanisms involved in determining arbovirus vector competence, or the ability of an arbovirus to infect and be transmitted by an arthropod vector, are still incompletely understood. It is well known that vector competence for a particular arbovirus can vary widely among different populations of a mosquito species, which is generally attributed to genetic differences between populations. What is less understood is the considerable variability (up to several logs) that is routinely observed in the virus titer between individual mosquitoes in a single experiment, even in mosquitoes from highly inbred lines. This extreme degree of variation in the virus titer between individual mosquitoes has been largely ignored in past studies. We investigated which biological factors can affect titer variation between individual mosquitoes of a laboratory strain of Aedes aegypti, the Orlando strain, after Sindbis virus infection. Greater titer variation was observed after oral versus intrathoracic infection, suggesting that the midgut barrier contributes to titer variability. Among the other factors tested, only the length of the incubation period affected the degree of titer variability, while virus strain, mosquito strain, mosquito age, mosquito weight, amount of blood ingested, and virus concentration in the blood meal had no discernible effect. We also observed differences in culture adaptability and in the ability to orally infect mosquitoes between virus populations obtained from low and high titer mosquitoes, suggesting that founder effects may affect the virus titer in individual mosquitoes, although other explanations also remain possible.


2022 ◽  
Vol 67 (4) ◽  
pp. 181-188
Author(s):  
Leilei Gong ◽  
Jun Han ◽  
Wenwen Yan ◽  
Yichen Qin

Abortion is one of the most common complications in pregnancy, and the cause of its occurrence in many cases remains unknown. The high prevalence and consequences of anxiety in women with spontaneous abortion could highlight the importance and role of post-abortion care (PAC). Detection and identification of biomarkers related to abortion and anxiety can effectively diagnose and prevent complications. Among the known biomarkers, microRNAs and the cortisol level have high potential. Therefore, the present study evaluated the effect of post-abortion care (PAC) on anxiety in women with spontaneous abortion based on MicroRNA-21 expression, cortisol level, and Fordyce happiness pattern. In this randomized clinical trial, 72 women with spontaneous abortion were studied and randomly divided into two groups of intervention (n = 36) and control (n = 36). Data were collected through a demographic questionnaire and HADS. To assess PAC, the intervention group was consulted in 8 sessions of 60 minutes in the first 72 hours after abortion. Meetings were held twice a week for four weeks. Both groups were followed up immediately after and one month after the intervention. To evaluate biological factors, 4ml of blood sample was obtained from the subjects. Blood cortisol levels were measured by the Cortisol Competitive Human ELISA Kit (Thermo-Fisher, USA), and microRNA-21 evaluation was performed by Real-time PCR technique. Data were analyzed using SPSS16 software. Results showed that before the intervention, there was no significant difference in the mean score of anxiety between the control and intervention groups (P> 0.05); But at the time immediately and one month after the intervention, there was a significant difference in the mean score of anxiety (p <0.001). The results of biological factors evaluation showed that in the intervention group, serum cortisol levels and microRNA-21 expression decreased significantly (p <0.05). In general, PAC based on the happiness pattern can control the anxiety of women with spontaneous abortion. Therefore, it is recommended as an effective and non-invasive intervention in preventing women's psychological problems after spontaneous abortion.


2022 ◽  
pp. 73-95
Author(s):  
Nicholas Gentry ◽  
Louis Ptacek ◽  
Ying-Hui Fu
Keyword(s):  

Hemato ◽  
2021 ◽  
Vol 3 (1) ◽  
pp. 17-37
Author(s):  
Anjum B. Khan ◽  
David Bowen

Myelodysplastic syndromes affect an older age group with a median age at onset in the eighth decade of life. As such, there is a relationship between the pathogenesis of MDS and age-related processes affecting haematopoietic stem/progenitor cells and/or the bone marrow microenvironment. MDS with an onset in younger people may be associated with recognised hereditary myeloid malignancy syndromes, and ‘forme fruste’ presentations of inherited syndromes in later life are now increasingly recognised such as germline mutations in DDX41. The considerable clinical and research interest in hereditary disorders is reflected in the relative emphasis within our manuscript. Prior chemo/radiotherapy is a clear cause of MDS but the predisposition factors for therapy-related MDS remain unclear. Clonal haematopoiesis is common in older people and may evolve to MDS, although once again, the biological factors driving this evolution are largely unknown. Finally, environmental exposure to genotoxic agents is likely to play only a minor role in the contemporary occupational/recreational setting.


Biomolecules ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 21
Author(s):  
Francesca Megiorni ◽  
Paola Pontecorvi ◽  
Giulia Gerini ◽  
Eleni Anastasiadou ◽  
Cinzia Marchese ◽  
...  

Coronavirus disease 2019 (COVID-19), the pandemic infection caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), presents with an extremely heterogeneous spectrum of symptoms and signs. The clinical manifestations seem to be correlated with disease severity. COVID-19 susceptibility and mortality show a significant sex imbalance, with men being more prone to infection and showing a higher rate of hospitalization and mortality compared to women. Such variability can be ascribed to both sex-related biological factors and gender-related behavioral cues. This review will discuss the potential mechanisms accounting for sex/gender influence in vulnerability to COVID-19. Cardiovascular diseases play a central role in determining COVID-19 outcome, whether they are pre-existent or arose upon infection. We will pay particular attention to the impact of sex and gender on cardiovascular manifestations related to COVID-19. Finally, we will discuss the sex-dependent variability in some biomarkers for the evaluation of COVID-19 infection and prognosis. The aim of this work is to highlight the significance of gendered medicine in setting up personalized programs for COVID-19 prevention, clinical evaluation and treatment.


Children ◽  
2021 ◽  
Vol 9 (1) ◽  
pp. 9
Author(s):  
Auriana Urfer ◽  
Hélène Turpin ◽  
Nevena Dimitrova ◽  
Ayala Borghini ◽  
Kerstin Jessica Plessen ◽  
...  

A preterm birth represents a stressful event having potentially negative long-term consequences. Thirty-three children born preterm (<33 weeks gestational age) and eleven full-term children participated in a nine-year longitudinal study. Perinatal Risk Inventory (PERI) was used at birth to assess the perinatal stress. Salivary cortisol, collected four times a day over two consecutive days, was measured with radioimmunoassay technique at six months and nine years to assess the hypothalamic-pituitary-adrenal (HPA) axis. Mothers reported post-traumatic symptoms on a self-report questionnaire 12 months after their child’s birth and children’s adjustment problems at 9 years of child age on the Child Behavior Checklist. Results showed a significant difference in cortisol regulation at nine years between preterm and full-term children but no differences in adjustment problems. Whereas biological factors (i.e., PERI, cortisol regulation at six months) explained cortisol at nine years, maternal post-traumatic symptoms were predictive of adjustment problems in their child. In conclusion, very preterm birth has some long-term consequences on the HPA-axis regulation at nine years. Although cortisol regulation is mostly influenced by biological factors, the presence of maternal post-traumatic symptoms predicts the manifestation of adjustment problems in both groups. This shows the importance of maternal psychological well-being for child development. Further research is needed to understand the exact consequences of premature birth on cortisol regulation and the implication for the child’s development and health.


2021 ◽  
Author(s):  
Mashael Aldamigh ◽  
Amaal H. Hassan ◽  
Ahlam A. Alahmadi

Helminthes infection causes extensive harm to the pigeon host. The purpose of this study was to observe histopathological changes caused by helminths infection. Thirty-five pigeons (C.L. Domestica) were purchased weekly from a bird's market from Al- Qassim region, Saudi Arabia. Out of the 35 pigeons examined, 9 pigeons (25.71%) were found infected with helminth parasites, which were identified as one cestode (Raillietina sp.), and one nematode (Ascaridia columbae). The infected pigeons suffered from growth retardation, emaciation, weakness, droopiness, and diarrhea. A lot of histopathological changes were seen in the intestine of infected pigeons including atrophy and distortion of villi, infiltration of inflammatory lymphocytic cells, erosion, and loss of the typical structure of the intestine, necrosis in villi, and blood vessels congestion. This study concludes, for the first time in AL-Qassim region-Saudi Arabia, that the infection with helminth parasites caused significant histopathological changes in the intestines of the infected pigeons, and this could lead to increased mortality to the infected pigeons. Further work is necessary in Saudi Arabia to determine the prevalence and biological factors that have a significant impact on the helminth parasites community.


2021 ◽  
Vol 33 (8) ◽  
pp. 082501
Author(s):  
Erin N Lang ◽  
Shelley A Claridge

Abstract Many technical-grade reagents, including oleylamine, are broadly used as ligands in nanocrystal synthesis, allowing for cost-effective, and more environmentally friendly, preparation of materials in useful quantities. Impurities can represent 30% or more of these reagent blends, and have frequently emerged as substantial drivers of nanocrystal morphology, assembly, or other physical properties, making it important to understand their composition. Some functional alkyl reagents are derived from natural sources (e.g. often beef tallow, in the case of oleylamine), introducing alkyl chain structures very different than those that might be expected as side products of synthesis from pure feedstocks. Additionally, impurities can exhibit variations based on biological factors (e.g. species, diet, season). In biology, blends of alkyl chains allow for surprisingly sophisticated function of amphiphiles in the cell membrane, pointing to the possibility of similar control in synthetic materials if reagent composition were either better controlled or better understood. Here, we provide brief context on the breadth of roles technical-grade impurities have played in nanocrystal materials, followed by a perspective on oleylamine impurities, their physical properties, and their potential contributions to nanomaterial function.


BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Stefan Wichmann ◽  
Siegfried Scherer ◽  
Zachary Ardern

Abstract Background Overlapping genes (OLGs) with long protein-coding overlapping sequences are disallowed by standard genome annotation programs, outside of viruses. Recently however they have been discovered in Archaea, diverse Bacteria, and Mammals. The biological factors underlying life’s ability to create overlapping genes require more study, and may have important applications in understanding evolution and in biotechnology. A previous study claimed that protein domains from viruses were much better suited to forming overlaps than those from other cellular organisms - in this study we assessed this claim, in order to discover what might underlie taxonomic differences in the creation of gene overlaps. Results After overlapping arbitrary Pfam domain pairs and evaluating them with Hidden Markov Models we find OLG construction to be much less constrained than expected. For instance, close to 10% of the constructed sequences cannot be distinguished from typical sequences in their protein family. Most are also indistinguishable from natural protein sequences regarding identity and secondary structure. Surprisingly, contrary to a previous study, virus domains were much less suitable for designing OLGs than bacterial or eukaryotic domains were. In general, the amount of amino acid change required to force a domain to overlap is approximately equal to the variation observed within a typical domain family. The resulting high similarity between natural sequences and those altered so as to overlap is mostly due to the combination of high redundancy in the genetic code and the evolutionary exchangeability of many amino acids. Conclusions Synthetic overlapping genes which closely resemble natural gene sequences, as measured by HMM profiles, are remarkably easy to construct, and most arbitrary domain pairs can be altered so as to overlap while retaining high similarity to the original sequences. Future work however will need to assess important factors not considered such as intragenic interactions which affect protein folding. While the analysis here is not sufficient to guarantee functional folding proteins, further analysis of constructed OLGs will improve our understanding of the origin of these remarkable genetic elements across life and opens up exciting possibilities for synthetic biology.


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