19 research outputs found
An Evaluation of Median and Paramedian Approach for Spinal Anaesthesia in Caesarean Delivery
Introduction : Spinal anesthesia can be achieved either through the median or paramedian approach. hence we evaluated the median and Paramedian Approach by following variables - Number of attempts, success of the block, presence of paraesthesia, the level of sensory level, and the incidence of head ache and lower back ache. Methods: The present Retrospective analytical comparative study is carried out on the records of 100 subjects . Records of the Patients were divided into two groups: Group ME (n=50) received spinal anaesthesia with median approach and Group PM (n=50) received through paramedian approach. Results: In Group ME, 12 (24%) patients developed PDPH vs. 6 (12%) in Group PM, which was not statistically significant . There was no significant difference in the incidence of paraesthesia in both groups. The mean duration of onset of PDPH was similar in both groups Conclusions : Our study shows that paramedian approach is equally effective and may be helpful in reducing the incidence of PDPH and paraesthesia, and it can be easily performed in pregnant patients
In vitro selection of Giardia duodenalis for Albendazole resistance identifies a -tubulin mutation at amino acid E198K
Benzimidazole-2-carbamate (BZ) compounds, including Albendazole (Alb), are one of just two drug classes approved to treat the gastrointestinal protist Giardia duodenalis. Benzimidazoles bind to the tubulin dimer interface overlapping the colchicine binding site (CBS) of β-tubulin, thereby inhibiting microtubule polymerisation and disrupting microtubule networks. These BZ compounds are widely used as anthelmintic, anti-fungal and anti-giardial drugs. However, in helminths and fungi, BZ-resistance is widespread and caused by specific point mutations primarily occurring at F167, E198 and F200 in β-tubulin isoform 1. BZ-resistance in Giardia is reported clinically and readily generated in vitro, with significant implications for Giardia control. In Giardia, BZ mode of action (MOA) and resistance mechanisms are presumed but not proven, and no mutations in β-tubulin have been reported in association with Alb resistance (AlbR). Herein, we undertook detailed in vitro drug-susceptibility screens of 13 BZ compounds and 7 Alb structural analogues in isogenic G. duodenalis isolates selected for AlbR and podophyllotoxin, another β-tubulin inhibitor, as well as explored cross-resistance to structurally unrelated, metronidazole (Mtz). AlbR lines exhibited co-resistance to many structural variants in the BZ-pharmacophore, and cross-resistance to podophyllotoxin. AlbR lines were not cross-resistant to Mtz, but MtzR lines had enhanced survival in Alb. Lastly, Alb analogues with longer thioether substituents had decreased potency against our AlbR lines. In silico modelling indicated the Alb-β-tubulin interaction in Giardia partially overlaps the CBS and corresponds to residues associated with BZ-resistance in helminths and fungi (F167, E198, F200). Sequencing of Giardia β-tubulin identified a single nucleotide polymorphism resulting in a mutation from glutamic acid to lysine at amino acid 198 (E198K). To our knowledge, this is the first β-tubulin mutation reported for protistan BZ-resistance. This study provides insight into BZ mode of action and resistance in Giardia, and presents a potential avenue for a genetic test for clinically resistance isolates
Multimodal regulation of encystation in Giardia duodenalis revealed by deep proteomics
Cyst formation in the parasitic protist Giardia duodenalis is critical to its transmission. Existing proteomic data quantifies only 17% of coding genes transcribed during encystation and does not cover the complete process from trophozoite to mature cyst. Using high-resolution mass spectrometry, we have quantified proteomic changes across encystation and compared this with published transcriptomic data. We reproducibly identified 3863 (64.5% of Giardia proteins) and quantified 3382 proteins (56.5% of Giardia proteins) over standard trophozoite growth (TY), during low-bile encystation priming (LB), 16 h into encystation (EC), and at cyst maturation (C). This work provides the first known expanded observation of encystation at the proteomic level and triples the coverage of previous encystation proteomes. One-third (1169 proteins) of the quantified proteome is differentially expressed in the mature cyst relative to the trophozoite, including proteasomal machinery, metabolic pathways, and secretory proteins. Changes in lipid metabolism indicated a shift in lipid species dependency during encystation. Consistent with this, we identified the first, putative lipid transporters in this species, representing the steroidogenic acute regulatory protein-related lipid transfer (StARkin), oxysterol binding protein related protein (ORP/Osh) and glycosphingolipid transfer protein (GLTP) families, and follow their differential expression over cyst formation. Lastly, we undertook correlation analyses of the transcriptome and proteome of trophozoites and cysts, and found evidence of post-transcriptional regulation of key protein classes (RNA binding proteins) and stage-specific genes (encystation markers) implicating translation-repression in encystation. We provide the most extensive proteomic analysis of encystation in Giardia to date and the first known exploration across its complete duration. This work identifies encystation as highly coordinated, involving major changes in proteostasis, metabolism and membrane dynamics, and indicates a potential role for post-transcriptional regulation, mediated through RNA-binding proteins. Together our work provides a valuable resource for Giardia research and the development of transmission-blocking anti-giardials
Adaptation of 3D Printing Technology for Fabrication of Economical Upper Limb Prostheses
Long-term stability of the genome structure of the cyanobacterium, <i>Dolichospermum</i> in a deep German lake
Dolichospermum is a cyanobacterial genus commonly associated with toxic blooms in lakes and brackish water bodies worldwide, and is a long-term resident of Lake Stechlin, northeastern Germany. In recent decades, shifts in the phosphorus loading and phytoplankton species composition have seen increased biomass of Dolichospermum during summer blooms from 1998, peaking around 2005, and declining after 2020. Cyanobacteria are known to rapidly adapt to new environments, facilitated by genome adaptation. To investigate the changes in genomic features that may have occurred in Lake Stechlin Dolichospermum during this time of increased phosphorus loading and higher biomass, whole genome sequence analysis was performed on samples of ten akinetes isolated from ten, 1 cm segments of a sediment core, representing a ∼45-year period from 1970 to 2017. Comparison of these genomes with genomes of extant isolates revealed a clade of Dolichospermum that clustered with the ADA-6 genus complex, with remarkable genome stability, without gene gain or loss events in response to recent environmental changes. The genome characteristics indicate that this species is suited to a deep-chlorophyll maximum, including additional light-harvesting and phosphorus scavenging genes. Population SNP analysis revealed two sub-populations that shifted in dominance as the lake transitioned between oligotrophic and eutrophic conditions. Overall, the results show little change within the population, despite diversity between extant populations from different geographic locations and the in-lake changes in phosphorus concentrations
Recent genetic exchanges and admixture shape the genome and population structure of the zoonotic pathogen Cryptosporidium parvum
Cryptosporidium parvum is a globally distributed zoonotic pathogen and a major cause of diarrhoeal disease in humans and ruminants. The parasite's life cycle comprises an obligatory sexual phase, during which genetic exchanges can occur between previously isolated lineages. Here, we compare 32 whole genome sequences from human- and ruminant-derived parasite isolates collected across Europe, Egypt and China. We identify three strongly supported clusters that comprise a mix of isolates from different host species, geographic origins, and subtypes. We show that: (1) recombination occurs between ruminant isolates into human isolates; (2) these recombinant regions can be passed on to other human subtypes through gene flow and population admixture; (3) there have been multiple genetic exchanges, and most are probably recent; (4) putative virulence genes are significantly enriched within these genetic exchanges, and (5) this results in an increase in their nucleotide diversity. We carefully dissect the phylogenetic sequence of two genetic exchanges, illustrating the long-term evolutionary consequences of these events. Our results suggest that increased globalization and close human-animal contacts increase the opportunity for genetic exchanges between previously isolated parasite lineages, resulting in spillover and spillback events. We discuss how this can provide a novel substrate for natural selection at genes involved in host-parasite interactions, thereby potentially altering the dynamic coevolutionary equilibrium in the Red Queens arms race
Global Population Genomics of Two Subspecies of <i>Cryptosporidium hominis</i> during 500 Years of Evolution
Cryptosporidiosis is a major global health problem and a primary cause of diarrhea, particularly in young children in low- and middle-income countries (LMICs). The zoonotic Cryptosporidium parvum and anthroponotic Cryptosporidium hominis cause most human infections. Here, we present a comprehensive whole-genome study of C. hominis, comprising 114 isolates from 16 countries within five continents. We detect two lineages with distinct biology and demography, which diverged circa 500 years ago. We consider these lineages two subspecies and propose the names C. hominis hominis and C. hominis aquapotentis (gp60 subtype IbA10G2). In our study, C. h. hominis is almost exclusively represented by isolates from LMICs in Africa and Asia and appears to have undergone recent population contraction. In contrast, C. h. aquapotentis was found in high-income countries, mainly in Europe, North America, and Oceania, and appears to be expanding. Notably, C. h. aquapotentis is associated with high rates of direct human-to-human transmission, which may explain its success in countries with well-developed environmental sanitation infrastructure. Intriguingly, we detected genomic regions of introgression following secondary contact between the subspecies. This resulted in high diversity and divergence in genomic islands of putative virulence genes, including muc5 (CHUDEA2_430) and a hypothetical protein (CHUDEA6_5270). This diversity is maintained by balancing selection, suggesting a co-evolutionary arms race with the host. Finally, we find that recent gene flow from C. h. aquapotentis to C. h. hominis, likely associated with increased human migration, maybe driving the evolution of more virulent C. hominis variants
Conservation, abundance, glycosylation profile, and localization of the TSP protein family in<i> Cryptosporidium</i> parvum
Cryptosporidium parvum is a zoonotic apicomplexan parasite and a common cause of diarrheal disease worldwide. The development of vaccines to prevent or limit infection remains an important goal for tackling cryptosporidiosis. At present, the only approved vaccine against any apicomplexan parasite targets a conserved adhesin possessing a thrombospondin repeat domain. C. parvum possesses 12 orthologous thrombospondin repeat domain-containing proteins known as CpTSP1-12, though little is known about these potentially important antigens. Here, we explore the architecture and conservation of the CpTSP protein family, as well as their abundance at the protein level within the sporozoite stage of the life cycle. We examine the glycosylation states of these proteins using a combination of glycopeptide enrichment techniques to demonstrate that these proteins are modified with C-, O-, and N-linked glycans. Using expansion microscopy, and an antibody against the C-linked mannose that is unique to the CpTSP protein family within C. parvum, we show that these proteins are found both on the cell surface and in structures that resemble the secretory pathway of C. parvum sporozoites. Finally, we generated a polyclonal antibody against CpTSP1 to show that it is found at the cell surface and within micronemes, in a pattern reminiscent of other apicomplexan motility-associated adhesins, and is present both in sporozoites and meronts. This work sheds new light on an understudied family of C. parvum proteins that are likely to be important to both parasite biology and the development of vaccines against cryptosporidiosis
Long-term stability of the genome structure of the cyanobacterium, Dolichospermum in a deep German lake
Dolichospermum is a cyanobacterial genus commonly associated with toxic blooms in lakes and brackish water bodies worldwide, and is a long-term resident of Lake Stechlin, northeastern Germany. In recent decades, shifts in the phosphorus loading and phytoplankton species composition have seen increased biomass of Dolichospermum during summer blooms from 1998, peaking around 2005, and declining after 2020. Cyanobacteria are known to rapidly adapt to new environments, facilitated by genome adaptation. To investigate the changes in genomic features that may have occurred in Lake Stechlin Dolichospermum during this time of increased phosphorus loading and higher biomass, whole genome sequence analysis was performed on samples of ten akinetes isolated from ten, 1 cm segments of a sediment core, representing a ∼45-year period from 1970 to 2017. Comparison of these genomes with genomes of extant isolates revealed a clade of Dolichospermum that clustered with the ADA-6 genus complex, with remarkable genome stability, without gene gain or loss events in response to recent environmental changes. The genome characteristics indicate that this species is suited to a deep-chlorophyll maximum, including additional light-harvesting and phosphorus scavenging genes. Population SNP analysis revealed two sub-populations that shifted in dominance as the lake transitioned between oligotrophic and eutrophic conditions. Overall, the results show little change within the population, despite diversity between extant populations from different geographic locations and the in-lake changes in phosphorus concentrations.Peer reviewe
VIVID A Web Application for Variant Interpretation and Visualization in Multi-dimensional Analyses
Large-scale comparative genomics- and population genetic studies generate enormous amounts of polymorphism data in the form of DNA variants. Ultimately, the goal of many of these studies is to associate genetic variants to phenotypes or fitness. We introduce VIVID, an interactive, user-friendly web application that integrates a wide range of approaches for encoding genotypic to phenotypic information in any organism or disease, from an individual or population, in three-dimensional (3D) space. It allows mutation mapping and annotation, calculation of interactions and conservation scores, prediction of harmful effects, analysis of diversity and selection, and 3D visualization of genotypic information encoded in Variant Call Format on AlphaFold2 protein models. VIVID enables the rapid assessment of genes of interest in the study of adaptive evolution and the genetic load, and it helps prioritizing targets for experimental validation. We demonstrate the utility of VIVID by exploring the evolutionary genetics of the parasitic protist Plasmodium falciparum, revealing geographic variation in the signature of balancing selection in potential targets of functional antibodies
