Cutaneous allergy and polymorphism of the tuberculosis pathogen

In recent years, there has been a profound revolution in the science of microbes. The world of these creatures, which seemed primitive and stable, turned out to be much more complex when studied in depth. On the basis of precise observations and facts, which have been accumulated over 50 years, it has become clear that it is necessary and possible to put this material in order and formulate a new doctrine, the doctrine of microbial variability. This new doctrine, a new interpretation of some of the already known phenomena, significantly expands our horizon, supplementing and deepening everything that was created by the founders of medical bacteriology. On the basis of the new doctrine, much in the clinic, i.e., in life, is illuminated differently.

Medical Bacteriology and Medical Genetics, 1880–1940: A Call for Synthesis

Between 1880 and 1920 the medical quest to unearth the causes of disease saw two pathbreaking discoveries. One was the bacteriological revolution – the identification of specific germs as causal agents of specific diseases (anthrax, tuberculosis, diphtheria, cholera and so on), and the simultaneous effort to develop disinfection techniques and immunisation measures to combat these diseases. The other was the rediscovery of Mendel’s laws of heredity and the resulting emergence of medical genetics, where an entire set of medical maladies (deafness, blindness, bodily deformities, haemophilia, Huntington’s chorea, feeble-mindedness and many mental diseases) were identified – rightly or wrongly – as genetically determined. The ‘germ theory of disease’ and the ‘gene theory of disease’ shared striking, all-too-often overlooked similarities. Both theories built on shared epistemological assumptions that influenced their explanatory mechanisms and their overall conceptual frameworks; both mobilised similar visual and linguistic vocabulary; both appropriated – and enforced – prevailing cultural and gender norms; and both enshrined broadly parallel hygienic practices. Reflecting similar social concerns, medical bacteriology and medical genetics acquired kindred scientific and societal configurations, which this paper highlights and scrutinises.

Molecular Characterization Of Extended Spectrum Betalactamases Genes (Blactxm And Blashv) In Enterobacteria Isolates In Medical Specimens In Lomé (Togo)

Background Extendum Bêtalactamases genes spread throughout the world. Many informations are known about it in Europe, Asia and elsewhere. In Africa particularly in Togo, we have lack informations although their prevalence are still increasing. The aim of this study is to identify the blaSHV and blaCTXM genes on Escherichia coli and Klebsiella pneumoniae strains isolated in two medical bacteriology laboratories in Lomé. Material and method 46 strains (20 Klebsiella pneumoniae, 23 Escherichia coli and 3 Enterobacter cloacae) isolated at Sylvanus Olympio Teaching Hospital (n = 31) and at Institut d’Hygiène (n = 15) in Lomé were investigated in search of blaSHV and blaCTXM through gene amplification. The strains were isolated from various samples in 2015 and 2016. An amplification of blaTEM was carried out in case of negativity to both genes. A sequencing of the amplicons was carried out then the sequences identified through blastX on the basis of NCBI data. Results We found 97.9% resistance to amoxicillin + clavulanic acid, gentamicin, levofloxacin and to sulfamethoxazole + trimethoprim. 8.7% of the strains were resistant to ertapenem. All the strains carried blaCTXM-15. In Klebsiella pneumoniae, blaSHV-1 blaSHV-11, blaSHV-28, blaSHV-61, blaSHV-77 were identified. Associations were found (blaSHV-1 / blaCTXM-15, blaSHV-11 / blaCTXM-15, blaSHV-28 / blaCTXM-15). blaTEM was identified on a strain of Enterobacter cloacae. Conclusion There is a diversity of blaSHV genes with a dominance of blaCTXM-15. blaTEM remains the gene to search for in case of absence of the two previous genes in ESBL strains in Lomé.

The eminence status of bacterial pigments under different aspects

Several bacteria such as Flavobacterium, Serratias, Chromobacterium and Streptomyces that produce different pigments are playing a significant role in various fields of sciences. Alternatively, current knowledge about bacterial pigments is limited to medical bacteriology, for instance their importance in virulence factors and protective features, however recently the investigators have revealed the supplementary consequence of pigments in food, textile and pharmaceutical aspects.

How old are bacterial pathogens?

Only few molecular studies have addressed the age of bacterial pathogens that infected humans before the beginnings of medical bacteriology, but these have provided dramatic insights. The global genetic diversity of Helicobacter pylori , which infects human stomachs, parallels that of its human host. The time to the most recent common ancestor (tMRCA) of these bacteria approximates that of anatomically modern humans, i.e. at least 100 000 years, after calibrating the evolutionary divergence within H. pylori against major ancient human migrations. Similarly, genomic reconstructions of Mycobacterium tuberculosis , the cause of tuberculosis, from ancient skeletons in South America and mummies in Hungary support estimates of less than 6000 years for the tMRCA of M. tuberculosis . Finally, modern global patterns of genetic diversity and ancient DNA studies indicate that during the last 5000 years plague caused by Yersinia pestis has spread globally on multiple occasions from China and Central Asia. Such tMRCA estimates provide only lower bounds on the ages of bacterial pathogens, and additional studies are needed for realistic upper bounds on how long humans and animals have suffered from bacterial diseases.