Seed bank has the potential for re-colonising urban stormwater ponds after reconstruction

Hydrobiologia - Urban stormwater ponds are important for flood protection and provide habitat for plants and animals in heavily sealed cities. Little is known about the diversity of plants in urban...     

Taxonomic notes on European taxa of Crataegus (Rosaceae)

In connection with systematic study of European taxa of Crataegus (Rosaceae subfam. Maloideae) lectotypes are designated for Crataegus monogyna f. subdigyna and C. monogyna var. ronnigeri. C. microphylla subsp. malýana is described as a taxon new to science and a key to the recognised taxa of C. microphylla and of the closely related C. rhipidophylla is given.     

Mushroom poisoning

In the research we included a total of 207 subjects with the dismissal diagnosis of "mycetismus", who were treated at the Department of Infectious Diseases, General Hospital Osijek, during the 1983-1992 period. 32 of them were children. There were 44.93% of men, 39.61% of women and 15.45% of children. The latent time > 6 hours was determined in 51 (25%) and < 6 hours in 75% of subjects. In 156 of patients with the latent time > 6 hours, "false" poisoning occured, while 51 patients experienced real mushroom toxins poisoning. At the admission to the hospital, in patients with the latent time > 6 hours, a pathological PT (protrombine time) was established only in women, leukocytosis in both women and children, increased concentration of GGT (gamma-glutamin-transferase) in men, increased AST (aspartate-aminotransferase) and ALT (alanin-aminotransferase) only in women, and increased urea in both women and children. After 24 hours, control measuring established high values of AST and ALT extended PT uremia and exalted amount of ammonia in blood in 11 of patients (2 men, 7 women and 2 children). They had severe liver and kidney damage, the most probably caused by Amanita phalloides toxins. The latent time lasted 9 to 13 hours. Of the 11 above mentioned patients, 2 women, aged 74 and 43, and one girl, aged 6, died. No pathological laboratory parameters were established in 40 of subjects with the latent time of 6 and more hours, and the disease manifested through vomiting and diarrhea that lasted for several days. These subjects most probably suffered from mushroom toxins poisoning. Mushroom toxins irritate the mucuous membrane of the gastrointestinal tract, and there are many such poisonous mushrooms. There were no mortalities in this group of subjects.     

Prenatal household size and composition are associated with infant fecal bacterial diversity in Cebu,Philippines

Objectives

The gut microbiome (GM) connects physical and social environments to infant health. Since the infant GM affects immune system development, there is interest in understanding how infants acquire microbes from mothers and other household members.

Materials and Methods

As a part of the Cebu Longitudinal Health and Nutrition Survey (CLHNS), we paired fecal samples (proxy for the GM) collected from infants living in Metro Cebu, Philippines at 2 weeks (N = 39) and 6 months (N = 36) with maternal interviews about prenatal household composition. We hypothesized that relationships between prenatal household size and composition and infant GM bacterial diversity (as measured in fecal samples) would vary by infant age, as well as by household member age and sex. We also hypothesized that infant GM bacterial abundances would differ by prenatal household size and composition.

Results

Data from 16 S rRNA bacterial gene sequencing show that prenatal household size was the most precise estimator of infant GM bacterial diversity, and that the direction of the association between this variable and infant GM bacterial diversity changed between the two time points. The abundances of bacterial families in the infant GM varied by prenatal household variables.

Conclusions

Results highlight the contributions of various household sources to the bacterial diversity of the infant GM, and suggest that prenatal household size is a useful measure for estimating infant GM bacterial diversity in this cohort. Future research should measure the effect of specific sources of household bacterial exposures, including social interactions with caregivers, on the infant GM.

     

Recessive genetic variants affecting mating activity of males in natural populations ofDrosophila melanogaster

Mating activity of 115 wild males was compared with 88 homozygotes and 42 heterozygotes for their second chromosomes. Wild males, 48–96 hours old, inseminated on the average, 4.4±0.1 females per 24 hours. The hetero- and homozygotes for their second chromosomes (other chromosomes being randomly combined with those from the laboratory strain), inseminated on the average 2.8±0.2 and 2.0±0.2 females/24 h. respectively. There is no correlation between homozygotes and heterozygotes for the second chromosome and their wild ancestors which carried these chromosomes. Wild second chromosomes which in homozygous condition produced total sterility of their carriers, and some others which made for an unusually high activity in homozygous males, had on an average similar effects in wild carriers.This ariicle is warmly dedicated to Professor Theodosius Dobzhansky.     

A CRISPR response to pandemics?: Exploring the ethics of genetically engineering the human immune system

Ethical challenges should be addressed before gene editing is made available to improve the immune response against emerging viruses. Subject Categories: S&S: Economics & Business, Genetics, Gene Therapy & Genetic Disease, Immunology

In 1881, Louis Pasteur proved the “germ theory of disease”, namely that microorganisms are responsible for causing a range of diseases. Following Pasteur’s and Robert Koch’s groundbreaking work on pathogens, further research during the 20^th century elucidated how the immune system fends off disease‐causing microorganisms from a molecular perspective.The COVID‐19 pandemic has again focused scientific and public attention on immunology not the least owing to the race of employing vaccines to halt the spread of the virus. Although most countries have now started vaccination programs to immunize a large part of the world''s population, the process will take time, vaccines may not be available to everyone, and a number of unresolved issues remain including the potential contagiousness of vaccinated individuals and the duration of protection (Polack et al, 2020).It would therefore be extremely helpful from a public health perspective—and indeed lifesaving for those with elevated risk of developing severe course of the disease—if we could boost the human immune system by other means to better fight off SARS‐CoV‐2 and possibly other viruses. Recent studies showing that some individuals may be less susceptible to contract severe COVID‐19 depending on their genetic status support such visions (COVID‐19 Host Genetics Initiative, 2020). This could eventually inspire research projects on gene therapy with the aim of generally enhancing immunity against viral infections.

It would therefore be extremely helpful from a public health perspective […] if we could boost the human immune system by other means to better fight off SARS‐CoV‐2 …

The idea of genetically enhancing the human immune response is not new and spread from academic circles to policymakers and the general public even before the pandemic, when He Jiankui announced in November 2018 the birth of genetically edited twins who, he claimed, were resistant to HIV. The public outcry was massive, not only because He violated standards of methodological rigor and research ethics, but also because of fundamental doubts about the wisdom and legitimacy of human germline manipulation (Schleidgen et al, 2020).Somatic gene therapy has been met with a less categorical rejection, but it has also been confronted with skepticism when major setbacks or untoward events occurred, such as the death of Jesse Gelsinger during an early clinical trial for gene therapy in 1999. Nonetheless, given the drastic impact the current pandemic has on so many lives, there may be a motivation to put concerns aside. In fact, even if we managed to get rid of COVID‐19 owing to vaccines—or at least to keep its infectiousness and mortality low—another virus will appear sooner or later; an improved resistance to viral pathogens—including coronaviruses—would be an important asset.Interventions to boost the immune system could in fact make use of either germline gene editing, as has been the case of the Chinese twins, or through somatic gene editing. The first requires time and only the next generation would potentially benefit while the latter could be immediately applied and theoretically used to deal with the ongoing COVID‐19 pandemic.

Interventions to boost the immune system could in fact make use of either germline gene editing, as has been the case of the Chinese twins, or through somatic gene editing.

     

The causes of instability of artificial mini-chromosomes in yeasts mutant for chl genes

In mutants chl2, chl3, chl5, and chl6, which control mitotic chromosome transmission, the behaviour of the centromeric plasmids with various genes was analyzed. The main cause of chromosome instability in chl2, chl5, and chl6 is chromosome loss during cell division (1:0 segregation). The main cause of chromosome instability in chl3. is nondisjunction (2:0 segregation). According to this, the chl3 mutant, but not other chl's, cannot maintain the mini-chromosome with SUP11 gene. This gene causes cell death in high copy number. Chromosome nondisjunction in chl3 is also confirmed by the data on the mini-chromosome carrying CUP1 gene responsible for copper-resistance in yeast. The copper resistancy level in chl3 transformants is much higher than in chl5 or wild type transformants. Elevated copper resistance of chl3 transformants is caused by the transit accumulation of CUP1-carrying mini-chromosome in part of the cell population as a result of segregation mistakes upon cell divisions. Thus, the CHL3 gene is a new gene that controls the process of mitotic chromosome disjunction in yeast.