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(Sub-)Antarctic endemic cyanobacteria from benthic mats are rare and have restricted geographic distributions
No full textThe Antarctic terrestrial macrobiota are highly endemic and biogeographically structured, but whether this also holds true for microbial groups remains poorly understood. We studied the biogeographic patterns of Antarctic cyanobacteria from benthic microbial mats sampled in 84 lakes from two sub-Antarctic islands, as well as from eight Antarctic Conservation Biogeographic Regions (ACBRs) which were previously defined based mainly on macroscopic taxa. Analysis of 16S rRNA gene sequences revealed that Antarctic and sub-Antarctic lakes host significantly different cyanobacterial communities, yet that the bioregionalization pattern did not correspond to the division into ACBRs. Both Antarctic and sub-Antarctic lakes contain a high number of potentially endemic taxa (41% of the total diversity), of which 33.3% attain a relative abundance of < 1%. Our findings highlight the uniqueness of Antarctic microbiota and the need for increased protection of inland waters in both Antarctica and the sub-Antarctic islands.The Antarctic terrestrial macrobiota are highly endemic and biogeographically structured, but whether this also holds true for microbial groups remains poorly understood. We studied the biogeographic patterns of Antarctic cyanobacteria from benthic microbial mats sampled in 84 lakes from two sub-Antarctic islands, as well as from eight Antarctic Conservation Biogeographic Regions (ACBRs) which were previously defined based mainly on macroscopic taxa. Analysis of 16S rRNA gene sequences revealed that Antarctic and sub-Antarctic lakes host significantly different cyanobacterial communities, yet that the bioregionalization pattern did not correspond to the division into ACBRs. Both Antarctic and sub-Antarctic lakes contain a high number of potentially endemic taxa (41% of the total diversity), of which 33.3% attain a relative abundance of < 1%. Our findings highlight the uniqueness of Antarctic microbiota and the need for increased protection of inland waters in both Antarctica and the sub-Antarctic islands.
A quality analysis of the measurement properties of the clinician-reported outcome measures for vitiligo and of the studies assessing them : a systematic review
No full textBackground/Objective: Evaluating the measurement properties (MPs) of Clinician-Reported Outcome Measures (ClinROMs) is crucial for selecting appropriate instruments for vitiligo assessment. This review critically appraises the existing evidence on the MPs of the ClinROMs used in vitiligo. Methods: A systematic search was conducted in PubMed, Embase, and the Cochrane Library up to 20 February 2024, identifying validated ClinROMs in vitiligo. Studies were included if they provided original data on ClinROM development or analysis, excluding those solely validating other instruments. The assessment of ClinROM quality and risk of bias analysis followed COSMIN guidelines, and ClinROMs with the highest number of sufficiently rated MPs supported by a moderate/high Quality of Evidence (QoE) were identified per construct category (extent/repigmentation and evolution/activity). Results: This review included 22 studies evaluating 12 ClinROMs. For extent/repigmentation, the Vitiligo Area and Severity Index (VASI), Vitiligo Extent Score (VES), and VESplus each had four MPs rated sufficient with a moderate/high QoE. For evolution, the Vitiligo Disease Improvement Score (VDIS) and Vitiligo Disease Activity Score (VDAS) similarly had four MPs rated sufficient with a moderate/high QoE. For activity evaluated based on a single time point, the Vitiligo Signs of Activity Score (VSAS), the only validated ClinROM for visible signs of disease activity, had three MPs rated sufficient with a moderate/high QoE. Conclusions: Six ClinROMs demonstrated the highest quality ratings across two key constructs. However, none underwent a complete evaluation of all their MPs, highlighting the need for further validation and refinement.Background/Objective: Evaluating the measurement properties (MPs) of Clinician-Reported Outcome Measures (ClinROMs) is crucial for selecting appropriate instruments for vitiligo assessment. This review critically appraises the existing evidence on the MPs of the ClinROMs used in vitiligo. Methods: A systematic search was conducted in PubMed, Embase, and the Cochrane Library up to 20 February 2024, identifying validated ClinROMs in vitiligo. Studies were included if they provided original data on ClinROM development or analysis, excluding those solely validating other instruments. The assessment of ClinROM quality and risk of bias analysis followed COSMIN guidelines, and ClinROMs with the highest number of sufficiently rated MPs supported by a moderate/high Quality of Evidence (QoE) were identified per construct category (extent/repigmentation and evolution/activity). Results: This review included 22 studies evaluating 12 ClinROMs. For extent/repigmentation, the Vitiligo Area and Severity Index (VASI), Vitiligo Extent Score (VES), and VESplus each had four MPs rated sufficient with a moderate/high QoE. For evolution, the Vitiligo Disease Improvement Score (VDIS) and Vitiligo Disease Activity Score (VDAS) similarly had four MPs rated sufficient with a moderate/high QoE. For activity evaluated based on a single time point, the Vitiligo Signs of Activity Score (VSAS), the only validated ClinROM for visible signs of disease activity, had three MPs rated sufficient with a moderate/high QoE. Conclusions: Six ClinROMs demonstrated the highest quality ratings across two key constructs. However, none underwent a complete evaluation of all their MPs, highlighting the need for further validation and refinement.A
An experimental investigation on the effect of incorporating natural fibers on the mechanical and durability properties of concrete by using treated hybrid fiber-reinforced concrete application
No full textThis research explores the use of treated hybrid natural fibers—wheat straw and bamboo—as reinforcements in concrete for pavement applications. Motivated by environmental and economic benefits, the study investigates how these fibers can enhance the mechanical and durability properties of concrete. Wheat straw fibers, abundant in Ethiopia due to extensive wheat farming, help control micro-cracks and increase the tensile strength of concrete, while bamboo fibers, also locally available, reduce macro-crack propagation and improve concrete toughness. To prepare these fibers, wheat straw was cut to 25 mm in length and bamboo fibers were treated with a 5% sodium hydroxide solution before being cut into lengths of 30, 45, and 60 mm. A concrete mix targeting a cube compressive strength of 30 MPa incorporated 0.1% wheat straw fibers, with varying bamboo fiber contents (0.5%, 1%, and 1.5%) by weight of cement. The results indicate that the uniquely treated hybrid natural fiber-reinforced concrete mix exhibits noticeable enhancements in mechanical properties, with approximate increases of 4.16%, 8.80%, and 8.93% at 7, 28, and 56 days, respectively. Furthermore, the split tensile strength, flexural strength, and durability properties of the concrete were significantly improved by the proposed fiber concentration and length compared to the control concrete mix design. This treatment also shifted the failure mode of the concrete from brittle to ductile and enhanced its energy absorption capacity up to 7.88% higher than that of the control concrete. Based on the AASHTO 1993 pavement design guidelines, this fiber-reinforced concrete reduces pavement thickness by 11% compared to the control concrete while improving post-cracking behavior. This hybrid natural fiber-reinforced concrete presents a promising, sustainable, and eco-friendly alternative for rigid pavement construction.This research explores the use of treated hybrid natural fibers—wheat straw and bamboo—as reinforcements in concrete for pavement applications. Motivated by environmental and economic benefits, the study investigates how these fibers can enhance the mechanical and durability properties of concrete. Wheat straw fibers, abundant in Ethiopia due to extensive wheat farming, help control micro-cracks and increase the tensile strength of concrete, while bamboo fibers, also locally available, reduce macro-crack propagation and improve concrete toughness. To prepare these fibers, wheat straw was cut to 25 mm in length and bamboo fibers were treated with a 5% sodium hydroxide solution before being cut into lengths of 30, 45, and 60 mm. A concrete mix targeting a cube compressive strength of 30 MPa incorporated 0.1% wheat straw fibers, with varying bamboo fiber contents (0.5%, 1%, and 1.5%) by weight of cement. The results indicate that the uniquely treated hybrid natural fiber-reinforced concrete mix exhibits noticeable enhancements in mechanical properties, with approximate increases of 4.16%, 8.80%, and 8.93% at 7, 28, and 56 days, respectively. Furthermore, the split tensile strength, flexural strength, and durability properties of the concrete were significantly improved by the proposed fiber concentration and length compared to the control concrete mix design. This treatment also shifted the failure mode of the concrete from brittle to ductile and enhanced its energy absorption capacity up to 7.88% higher than that of the control concrete. Based on the AASHTO 1993 pavement design guidelines, this fiber-reinforced concrete reduces pavement thickness by 11% compared to the control concrete while improving post-cracking behavior. This hybrid natural fiber-reinforced concrete presents a promising, sustainable, and eco-friendly alternative for rigid pavement construction.A
Review on activity-based detection of doping substances and growth promotors in biological matrices : do bioassays deserve a place in control programs?
No full textBackground: Control programs such as anti-doping control and growth promotor residue surveillance programs are challenged by the emergence of designer drugs and the use of low-level drug cocktails. In order to cope with these challenges, the use of bioassays, measuring biological activity in a matrix, has been explored over the past two decades as a universal means to detect (combinations of) unknown drugs, regardless of their chemical structure. Results: This review compiles the experience on the use of activity-based assays to detect doping substances and growth promotors in biological matrices of humans (athletes) or live animals (race and/or food-producing animals). The aim is to learn from the scientific progress, going from initial research to the recent revival of this topic. Bioassay improvements and remaining limitations are discussed, along with a rational evaluation of possible applications of bioassays in control programs at their current functionality. Limitations include the possible interference by endogenous compounds and the challenge to detect metabolically activated (pro-)drugs. Nevertheless, successful validation of bioassays has been achieved, ensuring robust, reliable and valid results. Significance: We conclude by proposing three applications of bioassays that provide added-value to the current testing procedures: (i) characterization of compounds to provide indisputable proof of biological effects and to prioritize legislative (cf. expansion of bans) and research endeavors (cf. method development), (ii) bioassay- based screening of biological samples to direct intelligent sample storage, sample retesting and targeted athlete testing, (iii) bioassay-guided identification of drugs to overcome the challenges of suspicious peak selection, related to high-resolution techniques.Background: Control programs such as anti-doping control and growth promotor residue surveillance programs are challenged by the emergence of designer drugs and the use of low-level drug cocktails. In order to cope with these challenges, the use of bioassays, measuring biological activity in a matrix, has been explored over the past two decades as a universal means to detect (combinations of) unknown drugs, regardless of their chemical structure. Results: This review compiles the experience on the use of activity-based assays to detect doping substances and growth promotors in biological matrices of humans (athletes) or live animals (race and/or food-producing animals). The aim is to learn from the scientific progress, going from initial research to the recent revival of this topic. Bioassay improvements and remaining limitations are discussed, along with a rational evaluation of possible applications of bioassays in control programs at their current functionality. Limitations include the possible interference by endogenous compounds and the challenge to detect metabolically activated (pro-)drugs. Nevertheless, successful validation of bioassays has been achieved, ensuring robust, reliable and valid results. Significance: We conclude by proposing three applications of bioassays that provide added-value to the current testing procedures: (i) characterization of compounds to provide indisputable proof of biological effects and to prioritize legislative (cf. expansion of bans) and research endeavors (cf. method development), (ii) bioassay- based screening of biological samples to direct intelligent sample storage, sample retesting and targeted athlete testing, (iii) bioassay-guided identification of drugs to overcome the challenges of suspicious peak selection, related to high-resolution techniques.A
The molecular causes and clinical consequences of dysregulation at the HM13 locus in cancer
No full textPublic defense: 2025-01-28D
Unraveling the genetic landscape of foot arch morphology : a systematic review of single nucleotide polymorphisms
No full textVariations in foot arch morphology, including flat feet (pes planus) and high arches (pes cavus), range from asymptomatic to debilitating. Limited research exists on the genetics of foot arch geometry. This systematic review aims to identify single nucleotide polymorphisms (SNPs) linked to foot arch morphology. The review protocol was registered in PROSPERO (CRD42024537877). PubMed, The Cochrane Library, Embase, and Web of Science were searched for studies on SNPs related to foot arch morphology published up to December 2023. Nineteen eligible studies (2006-2020) identified 137 SNPs across conditions affecting connective tissue (12 studies, e.g., Marfan Syndrome), nerves (six studies, e.g., Charcot-Marie-Tooth Disease), and muscles (one study, e.g., Distal Arthrogryposis Syndromes). While no studies directly linked SNPs to foot arch morphology, three explored SNPs in genetic diseases associated with foot arch variations. Pes planus was linked to connective tissue disorders, and pes cavus to neuropathies and myopathies. Only two replicated SNPs were found. This review found no direct studies of SNPs influencing foot arch morphology, highlighting a significant research gap. Future research should examine SNPs in larger cohorts to differentiate natural variations from pathology-driven deformities. To enhance reproducibility, standardized methodologies, and a unified genetic database (including phenotypic data on common traits) should be developed.Variations in foot arch morphology, including flat feet (pes planus) and high arches (pes cavus), range from asymptomatic to debilitating. Limited research exists on the genetics of foot arch geometry. This systematic review aims to identify single nucleotide polymorphisms (SNPs) linked to foot arch morphology. The review protocol was registered in PROSPERO (CRD42024537877). PubMed, The Cochrane Library, Embase, and Web of Science were searched for studies on SNPs related to foot arch morphology published up to December 2023. Nineteen eligible studies (2006-2020) identified 137 SNPs across conditions affecting connective tissue (12 studies, e.g., Marfan Syndrome), nerves (six studies, e.g., Charcot-Marie-Tooth Disease), and muscles (one study, e.g., Distal Arthrogryposis Syndromes). While no studies directly linked SNPs to foot arch morphology, three explored SNPs in genetic diseases associated with foot arch variations. Pes planus was linked to connective tissue disorders, and pes cavus to neuropathies and myopathies. Only two replicated SNPs were found. This review found no direct studies of SNPs influencing foot arch morphology, highlighting a significant research gap. Future research should examine SNPs in larger cohorts to differentiate natural variations from pathology-driven deformities. To enhance reproducibility, standardized methodologies, and a unified genetic database (including phenotypic data on common traits) should be developed.A
