How did specific useful protein sequences arise from simpler molecules at the origin of life? This seemingly needle-in-a-haystack problem has remarkably close resemblance to the old Protein Folding Problem, for which the solution is now known from statistical physics. Based on the logic that Origins must have come only after there was an operative evolution mechanism-which selects on phenotype, not genotype-we give a perspective that proteins and their folding processes are likely to have been the primary driver of the early stages of the origin of life.
View Article and Find Full Text PDFThe origin of life must have been preceded by Darwin-like evolutionary dynamics that could propagate it. How did that adaptive dynamics arise? And from what prebiotic molecules? Using evolutionary invasion analysis, we develop a universal framework for describing any origin story for evolutionary dynamics. We find that autocatalysts, i.
View Article and Find Full Text PDFAs advanced treatments are becoming increasingly feasible in veterinary medicine, the evaluation of the health-related quality of life (HRQOL) of treated animals is becoming more relevant. We evaluated owner-perceived HRQOL of 10 dogs that underwent craniotomy for meningioma resection between 2002 and 2022 at our institution through telephone interview. For this purpose, we developed a disease-specific questionnaire containing 52 items (mostly of scoring nature) patterned after previously validated instruments and organised into eight domains.
View Article and Find Full Text PDFThe LUX-ZEPLIN experiment is a dark matter detector centered on a dual-phase xenon time projection chamber operating at the Sanford Underground Research Facility in Lead, South Dakota, USA. This Letter reports results from LUX-ZEPLIN's first search for weakly interacting massive particles (WIMPs) with an exposure of 60 live days using a fiducial mass of 5.5 t.
View Article and Find Full Text PDFWhen life arose from prebiotic molecules 3.5 billion years ago, what came first? Informational molecules (RNA, DNA), functional ones (proteins), or something else? We argue here for a different logic: rather than seeking a , we seek a Biology required an ability to evolve before it could choose and optimise materials. We hypothesise that the was rooted in the Modelling shows how short random peptides can collapse in water and catalyse the elongation of others, powering both increased folding stability and emergent autocatalysis through a disorder-to-order process.
View Article and Find Full Text PDFDarwinian evolution (DE)-biology's powerful process of adaptation-is remarkably different from other known dynamical processes. It is antithermodynamic, driving away from equilibrium; it has persisted for 3.5 billion years; and its target, fitness, can seem like "Just So" stories.
View Article and Find Full Text PDFDespite several reports worldwide documenting the presence of in samples derived from ectoparasites, animals and more recently humans, genomic information of these specimens remains scarce, and when available, is usually limited to small genomic fragments of limited value. We generated complete sequences for two conserved (17-kDa antigen gene and ) and three variable (, and ) genes in five DNA samples detected in cat and dog fleas in Peru. Complete gene sequences were used to conduct multi-locus sequence typing and phylogenetic analyses to assess diversity and infer relationships among strains and other reference sequences.
View Article and Find Full Text PDFBackground: Antimicrobial stewardship programs promote the appropriate use of antimicrobial substances through the implementation of evidence-based, active and passive interventions. We analyzed the effect of a computer-assisted intervention on antimicrobial use in a tertiary care hospital.
Methods: Between 2011 and 2016 we introduced an electronic alert for patients being prescribed meropenem, voriconazole and caspofungin.
J Phys Chem B
August 2021
Recent experiments demonstrate molecular chemotaxis or altered diffusion rates of enzymes in the presence of their own substrates. We show here an important implication, namely, that if a nanoscale catalyst A produces a small-molecule ligand product L which is the substrate of another catalyst B, the two catalysts will attract each other. We explore this nonequilibrium producer recruitment force (ProRec) in a reaction-diffusion model.
View Article and Find Full Text PDFVitamin D has been claimed to be effective in the response to infections, including the respiratory syndrome coronavirus 2 (SARS-CoV-2). It is supposed that lockdown measures and fear of SARS-CoV-2 infection might reduce vitamin D levels through the modification of lifestyle. However, very few data exist on the association between lockdown measures and vitamin D status in humans.
View Article and Find Full Text PDFBackground: Transmission of dengue virus (DENV) from humans to mosquitoes represents a critical component of dengue epidemiology. Examinations of this process have generally been hampered by a lack of methods that adequately represent natural acquisition of DENV by mosquitoes from humans. In this study, we assessed artificial and natural blood feeding methods based on rates of DENV infection and dissemination within mosquitoes for use in a field-based epidemiological cohort study in Iquitos, Peru.
View Article and Find Full Text PDFWhile studying rickettsial infections in Peru, we detected Rickettsia asembonensis in fleas from domestic animals. We characterized 5 complete genomic regions (17kDa, gltA, ompA, ompB, and sca4) and conducted multilocus sequence typing and phylogenetic analyses. The molecular isolate from Peru is distinct from the original R.
View Article and Find Full Text PDFUsing a large, passive, febrile surveillance program in Iquitos, Peru, we retrospectively tested human blood specimens for scrub typhus group orientiae by ELISA, immunofluorescence assay, and PCR. Of 1,124 participants, 60 (5.3%) were seropositive, and 1 showed evidence of recent active infection.
View Article and Find Full Text PDFAging increases the risk of cardiovascular disease and metabolic syndrome. Alterations in epicardial fat play an important pathophysiological role in coronary artery disease and hypertension. We investigated the impact of normal aging on obesity-related genes in epicardial fat.
View Article and Find Full Text PDFA highly stable setup for stimulated Raman scattering (SRS) microscopy is presented. It is based on a two-branch femtosecond Er:fiber laser operating at a 40 MHz repetition rate. One of the outputs is directly modulated at the Nyquist frequency with an integrated electro-optic modulator (EOM).
View Article and Find Full Text PDFUsing a large, passive, clinic-based surveillance program in Iquitos, Peru, we characterized the prevalence of rickettsial infections among undifferentiated febrile cases and obtained evidence of pathogen transmission in potential domestic reservoir contacts and their ectoparasites. Blood specimens from humans and animals were assayed for spotted fever group rickettsiae (SFGR) and typhus group rickettsiae (TGR) by ELISA and/or PCR; ectoparasites were screened by PCR. Logistic regression was used to determine associations between patient history, demographic characteristics of participants and symptoms, clinical findings and outcome of rickettsial infection.
View Article and Find Full Text PDFThis study evaluated the effects of continuous and discontinuous work-reinforcer schedule arrangements on skill acquisition for three students with autism. Participants were initially exposed to both schedules in an alternating schedules condition where they were taught different but equivalent skills for each schedule. In the discontinuous schedule condition, participants completed work in small increments to gain access to a reinforcer for short periods of time.
View Article and Find Full Text PDFClones of tomato golden mosaic virus (TGMV), a key model for geminivirus research, have been transmitted back to their original host tomato for the first time. In contrast to the high pathogenicity in other solanaceous species, TGMV induced only very mild symptoms: a few chlorotic spots on the leaf lamina for the common variant (formerly strain cs), and limited vein yellowing for the yellow vein variant (yv). Symptoms disappeared over time, though viral DNA remained detectable in newly developed leaves.
View Article and Find Full Text PDFThe reported prevalence of vancomycin-resistant Enterococcus faecium (VRE) in Switzerland for the years 2008-2010 has been low at <5%. At the University Hospital Zurich, 17 cases of VRE were detected between 28 December 2009 and 15 February 2010. Nine cases were diagnosed clinically; eight cases were detected by rectal screening.
View Article and Find Full Text PDFTranspl Infect Dis
August 2012
A male Caucasian patient developed nodular erythematous skin lesions, malaise, and clinical signs of progressive heart failure 4 months after renal transplantation. Bronchoscopy with bronchoalveolar lavage performed for a small infiltrate seen on a computed tomography scan revealed Trypanosoma, which had at this point not been suspected as a cause. Parasitemia was present, and reactivation rather than transmission of Chagas' disease was established by performing polymerase chain reaction and serology in the donor and recipient.
View Article and Find Full Text PDFMixed viral infections can induce different changes in symptom development, genome accumulation and tissue tropism. These issues were investigated for two phloem-limited begomoviruses, Abutilon mosaic virus (AbMV) and Tomato yellow leaf curl Sardinia virus (TYLCSV) in Nicotiana benthamiana plants doubly infected by either the potyvirus Cowpea aphid-borne mosaic virus (CABMV) or the tombusvirus Artichoke mottled crinkle virus (AMCV). Both RNA viruses induced an increase of the amount of AbMV, led to its occasional egress from the phloem and induced symptom aggravation, while the amount and tissue tropism of TYLCSV were almost unaffected.
View Article and Find Full Text PDFWe have studied five women with genital tuberculosis (TB), which is an uncommon disease in Western European countries. However, young women that have emigrated from a country with high TB-prevalence and have complaints of unexplained infertility and nonspecific abdominal or pelvic symptoms should be checked for this disease. Because genital tuberculosis frequently causes infertility, early diagnosis and treatment are crucial, necessitating rapid microscopic, histological, and microbiological (culture) testing in suspected cases.
View Article and Find Full Text PDFThe geminivirus Abutilon mosaic virus (AbMV) encodes two proteins which are essential for viral spread within plants. The nuclear shuttle protein (NSP) transfers viral DNA between the nucleus and cytoplasm, whereas the movement protein (MP) facilitates transport between cells through plasmodesmata and long-distance via phloem. An inducible overexpression system for epitope-tagged NSP and MP in plants yielded unprecedented amounts of both proteins.
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