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The retroviral Gag precursor plays a central role in the selection and packaging of viral genomic RNA (gRNA) by binding to virus-specific packaging signal(s) (psi or ψ). Previously, we mapped the feline immunodeficiency virus (FIV) ψ to two discontinuous regions within the 5' end of the gRNA that assumes a higher order structure harboring several structural motifs. To better define the region and structural elements important for gRNA packaging, we methodically investigated these FIV ψ sequences using genetic, biochemical, and structure-function relationship approaches. Our mutational analysis revealed that the unpaired U85CUG88 stretch within FIV ψ is crucial for gRNA encapsidation into nascent virions. High-throughput selective 2' hydroxyl acylation analyzed by primer extension (hSHAPE) performed on wild type (WT) and mutant FIV ψ sequences, with substitutions in the U85CUG88 stretch, revealed that these mutations had limited structural impact and maintained nucleotides 80-92 unpaired, as in the WT structure. Since these mutations dramatically affected packaging, our data suggest that the single-stranded U85CUG88 sequence is important during FIV RNA packaging. Filter-binding assays performed using purified FIV Pr50Gag on WT and mutant U85CUG88 ψ RNAs led to reduced levels of Pr50Gag binding to mutant U85CUG88 ψ RNAs, indicating that the U85CUG88 stretch is crucial for ψ RNA-Pr50Gag interactions. Delineating sequences important for FIV gRNA encapsidation should enhance our understanding of both gRNA packaging and virion assembly, making them potential targets for novel retroviral therapeutic interventions, as well as the development of FIV-based vectors for human gene therapy.
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Virus de la Inmunodeficiencia Felina , Animales , Gatos , Humanos , Virus de la Inmunodeficiencia Felina/genética , Virus de la Inmunodeficiencia Felina/metabolismo , ARN Guía de Sistemas CRISPR-Cas , ARN Viral/química , Sitios de Unión , Genómica , Ensamble de Virus/genéticaRESUMEN
Globally women face inequality in cancer outcomes; for example, smaller improvements in life expectancy due to decreased cancer-related deaths than men (0.5 vs 0.8 years, 1981-2010). However, comprehensive global evidence on the burden of cancer among women (including by reproductive age spectrum) as well as disparities by region, remains limited. This study aimed to address these evidence gaps by considering 34 cancer types in 2020 and their projections for 2040. The cancer burden among women in 2020 was estimated using population-based data from 185 countries/territories sourced from GLOBOCAN. Mortality to Incidence Ratios (MIR), a proxy for survival, were estimated by dividing the age-standardised mortality rates by the age-standardised incidence rates. Demographic projections were performed to 2040. In 2020, there were an estimated 9.3 million cancer cases and 4.4 million cancer deaths globally. Projections showed an increase to 13.3 million (↑44%) and 7.1 million (↑60%) in 2040, respectively, with larger proportional increases in low- and middle-income countries. MIR among women was higher (poorer survival) in rare cancers and with increasing age. Countries with low Human Development Indexes (HDIs) had higher MIRs (69%) than countries with very high HDIs (30%). There was inequality in cancer incidence and mortality worldwide among women in 2020, which will further widen by 2040. Implementing cancer prevention efforts and providing basic cancer treatments by expanding universal health coverage through a human rights approach, expanding early screening opportunities and strengthening medical infrastructure are key to improving and ensuring equity in cancer control and outcomes.
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Neoplasias , Masculino , Humanos , Femenino , Neoplasias/epidemiología , Esperanza de Vida , Incidencia , Predicción , Carga Global de Enfermedades , Salud GlobalRESUMEN
Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is responsible for coronavirus disease of 2019 (COVID-19) that infected more than 760 million people worldwide with over 6.8 million deaths to date. COVID-19 is one of the most challenging diseases of our times due to the nature of its spread, its effect on multiple organs, and an inability to predict disease prognosis, ranging from being completely asymptomatic to death. Upon infection, SARS-CoV-2 alters the host immune response by changing host-transcriptional machinery. MicroRNAs (miRNAs) are regarded as post-transcriptional regulators of gene expression that can be perturbed by invading viruses. Several in vitro and in vivo studies have reported such dysregulation of host miRNA expression upon SARS-CoV-2 infection. Some of this could occur as an anti-viral response of the host to the viral infection. Viruses themselves can counteract that response by mounting their own pro-viral response that facilitates virus infection, an aspect which may cause pathogenesis. Thus, miRNAs could serve as possible disease biomarkers in infected people. In the current review, we have summarised and analysed the existing data about miRNA dysregulation in patients infected with SARS-CoV-2 to determine their concordance between studies, and identified those that could serve as potential biomarkers during infection, disease progression, and death, even in people with other co-morbidities. Having such biomarkers can be vital in not only predicting COVID-19 prognosis, but also the development of novel miRNA-based anti-virals and therapeutics which can become invaluable in case of the emergence of new viral variants with pandemic potential in the future.
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COVID-19 , MicroARNs , Virosis , Virus , Humanos , MicroARNs/genética , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Virus/genética , BiomarcadoresRESUMEN
Child malnutrition remains a significant concern in the Asia-Pacific region, with short birth intervals recognised as a potential risk factor. However, evidence of this association is inconclusive. This study aimed to systematically review the existing evidence and assess the summary effects of short birth interval on child malnutrition in the Asia-Pacific region. Five electronic databases were searched in May 2023 to identify relevant studies reporting the association between short birth interval and child malnutrition, including stunting, wasting, underweight, anaemia and overall malnutrition, in Asia-Pacific region between September 2000 and May 2023. Fixed-effects or random-effects meta-analysis was performed to estimate the summary effects of short birth interval on child malnutrition. Out of 56 studies meeting the inclusion criteria, 48 were included in quantitative synthesis through meta-analysis. We found a slightly higher likelihood of stunting (n = 25, odds ratio [OR] = 1.13; 95% confidence interval [CI]: 0.97-1.32) and overall malnutrition (n = 3, OR = 2.42; 95% CI: 0.88-6.65) among children born in short birth intervals compared to those with nonshort intervals, although the effect was not statistically significant. However, caution is warranted due to identified heterogeneity across studies. Subgroup analysis demonstrated significant effects of short birth intervals on child malnutrition in national-level studies and studies with larger sample sizes. These findings underscore short birth intervals as a significant contributor to child malnutrition in the Asia-Pacific region. Implementing effective policies and programs is vital to alleviate this burden, ultimately reducing child malnutrition and associated adverse outcomes, including child mortality.
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Intervalo entre Nacimientos , Trastornos de la Nutrición del Niño , Humanos , Asia/epidemiología , Intervalo entre Nacimientos/estadística & datos numéricos , Trastornos de la Nutrición del Niño/epidemiología , Trastornos del Crecimiento/epidemiología , Islas del Pacífico/epidemiología , Factores de Riesgo , NiñoRESUMEN
Retroviral RNA genome (gRNA) harbors cis-acting sequences that facilitate its specific packaging from a pool of other viral and cellular RNAs by binding with high-affinity to the viral Gag protein during virus assembly. However, the molecular intricacies involved during selective gRNA packaging are poorly understood. Binding and footprinting assays on mouse mammary tumor virus (MMTV) gRNA with purified Pr77Gag along with in cell gRNA packaging study identified two Pr77Gag binding sites constituting critical, non-redundant packaging signals. These included: a purine loop in a bifurcated stem-loop containing the gRNA dimerization initiation site, and the primer binding site (PBS). Despite these sites being present on both unspliced and spliced RNAs, Pr77Gag specifically bound to unspliced RNA, since only that could adopt the native bifurcated stem-loop structure containing looped purines. These results map minimum structural elements required to initiate MMTV gRNA packaging, distinguishing features that are conserved amongst divergent retroviruses from those perhaps unique to MMTV. Unlike purine-rich motifs frequently associated with packaging signals, direct involvement of PBS in gRNA packaging has not been documented in retroviruses. These results enhance our understanding of retroviral gRNA packaging/assembly, making it not only a target for novel therapeutic interventions, but also development of safer gene therapy vectors.
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Productos del Gen gag/metabolismo , Virus del Tumor Mamario del Ratón/metabolismo , Empalme del ARN , ARN Viral/metabolismo , Ensamble de Virus/genética , Animales , Sitios de Unión/genética , Cartilla de ADN , Dispersión Dinámica de Luz , Productos del Gen gag/genética , Genoma Viral , Virus del Tumor Mamario del Ratón/genética , Ratones , Conformación de Ácido Nucleico , Purinas , ARN Viral/genética , Reacción en Cadena en Tiempo Real de la PolimerasaRESUMEN
Novel strategies and materials have gained the attention of researchers due to the current pandemic, the global market high competition, and the resistance of pathogens against conventional materials. There is a dire need to develop cost-effective, environmentally friendly, and biodegradable materials to fight against bacteria using novel approaches and composites. Fused filament fabrication (FFF), also known as fused deposition modeling (FDM), is the most effective and novel fabrication method to develop these composites due to its various advantages. Compared to metallic particles alone, composites of different metallic particles have shown excellent antimicrobial properties against common Gram-positive and Gram-negative bacteria. This study investigates the antimicrobial properties of two sets of hybrid composite materials, i.e., Cu-PLA-SS and Cu-PLA-Al, are made using copper-enriched polylactide composite, one-time printed side by-side with stainless steel/PLA composite, and second-time with aluminum/PLA composite respectively. These materials have 90 wt.% of copper, 85 wt.% of SS 17-4, 65 wt.% of Al with a density of 4.7 g/cc, 3.0 g/cc, and 1.54 g/cc, respectively, and were fabricated side by side using the fused filament fabrication (FFF) printing technique. The prepared materials were tested against Gram-positive and Gram-negative bacteria such as Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), Pseudomonas aeruginosa (P. aeruginosa), Salmonella Poona (S. Poona), and Enterococci during different time intervals (5 min, 10 min, 20 min, 1 h, 8 h, and 24 h). The results revealed that both samples showed excellent antimicrobial efficiency, and 99% reduction was observed after 10 min. Hence, three-dimensional (3D) printed polymeric composites enriched with metallic particles can be utilized for biomedical, food packaging, and tissue engineering applications. These composite materials can also provide sustainable solutions in public places and hospitals where the chances of touching surfaces are higher.
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Antibacterianos , Antiinfecciosos , Animales , Antibacterianos/farmacología , Cobre , Escherichia coli , Bacterias Gramnegativas , Bacterias Grampositivas , Staphylococcus aureus , Aves , Antiinfecciosos/farmacología , Impresión TridimensionalRESUMEN
Inflammatory bowel disease, comprising Crohn's disease (CD) and ulcerative colitis (UC), is often debilitating. The disease etiology is multifactorial, involving genetic susceptibility, microbial dysregulation, abnormal immune activation, and environmental factors. Currently, available drug therapies are associated with adverse effects when used long-term. Therefore, the search for new drug candidates to treat IBD is imperative. The peroxisome proliferator-activated receptor-γ (PPARγ) is highly expressed in the colon. PPARγ plays a vital role in regulating colonic inflammation. 1,8-cineole, also known as eucalyptol, is a monoterpene oxide present in various aromatic plants which possess potent anti-inflammatory activity. Molecular docking and dynamics studies revealed that 1,8-cineole binds to PPARγ and if it were an agonist, that would explain the anti-inflammatory effects of 1,8-cineole. Therefore, we investigated the role of 1,8-cineole in colonic inflammation, using both in vivo and in vitro experimental approaches. Dextran sodium sulfate (DSS)-induced colitis was used as the in vivo model, and tumor necrosis factor-α (TNFα)-stimulated HT-29 cells as the in vitro model. 1,8-cineole treatment significantly decreased the inflammatory response in DSS-induced colitis mice. 1,8-cineole treatment also increased nuclear factor erythroid 2-related factor 2 (Nrf2) translocation into the nucleus to induce potent antioxidant effects. 1,8-cineole also increased colonic PPARγ protein expression. Similarly, 1,8-cineole decreased proinflammatory chemokine production and increased PPARγ protein expression in TNFα-stimulated HT-29 cells. 1,8-cineole also increased PPARγ promoter activity time-dependently. Because of its potent anti-inflammatory effects, 1,8-cineole may be valuable in treating IBD.
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Colitis Ulcerosa , Colitis , Enfermedades Inflamatorias del Intestino , Animales , Ratones , Antiinflamatorios/farmacología , Colitis/metabolismo , Colitis Ulcerosa/metabolismo , Colon/patología , Sulfato de Dextran , Eucaliptol/farmacología , Inflamación/metabolismo , Enfermedades Inflamatorias del Intestino/metabolismo , Ratones Endogámicos C57BL , Simulación del Acoplamiento Molecular , PPAR gamma/metabolismo , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
Since the Fourth Industrial Revolution, three-dimensional (3D) printing has become a game changer in manufacturing, particularly in bioengineering, integrating complex medical devices and tools with high precision, short operation times, and low cost. Antimicrobial materials are a promising alternative for combating the emergence of unforeseen illnesses and device-related infections. Natural antimicrobial materials, surface-treated biomaterials, and biomaterials incorporated with antimicrobial materials are extensively used to develop 3D-printed products. This review discusses the antimicrobial mechanisms of different materials by providing examples of the most commonly used antimicrobial materials in bioengineering and brief descriptions of their properties and biomedical applications. This review will help researchers to choose suitable antimicrobial agents for developing high-efficiency biomaterials for potential applications in medical devices, packaging materials, biomedical applications, and many more.
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Antiinfecciosos , Materiales Biocompatibles , Materiales Biocompatibles/farmacología , Impresión Tridimensional , Bioingeniería , Ingeniería Biomédica , Antiinfecciosos/farmacología , Antiinfecciosos/uso terapéuticoRESUMEN
IL-10 is a potent anti-inflammatory cytokine capable of suppressing a number of proinflammatory signals associated with intestinal inflammatory diseases, such as ulcerative colitis and Crohn's disease. Clinical use of human IL-10 (hIL-10) has been limited by anemia and thrombocytopenia following systemic injection, side effects that might be eliminated by a gut-restricted distribution. We have identified a transcytosis pathway used by cholix, an exotoxin secreted by nonpandemic forms of the intestinal pathogen Vibrio cholerae A nontoxic fragment of the first 386 aa of cholix was genetically fused to hIL-10 to produce recombinant AMT-101. In vitro and in vivo characterization of AMT-101 showed it to efficiently cross healthy human intestinal epithelium (SMI-100) by a vesicular transcytosis process, activate hIL-10 receptors in an engineered U2OS osteosarcoma cell line, and increase cellular phospho-STAT3 levels in J774.2 mouse macrophage cells. AMT-101 was taken up by inflamed intestinal mucosa and activated pSTAT3 in the lamina propria with limited systemic distribution. AMT-101 administered to healthy mice by oral gavage or to cynomolgus monkeys (nonhuman primates) by colonic spray increased circulating levels of IL-1R antagonist (IL-1Ra). Oral gavage of AMT-101 in two mouse models of induced colitis prevented associated pathological events and plasma cytokine changes. Overall, these studies suggest that AMT-101 can efficiently overcome the epithelial barrier to focus biologically active IL-10 to the intestinal lamina propria.
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Colitis/metabolismo , Interleucina-10/metabolismo , Mucosa Intestinal/metabolismo , Animales , Células Cultivadas , Colon/metabolismo , Enfermedad de Crohn/metabolismo , Citocinas/metabolismo , Femenino , Humanos , Inflamación/metabolismo , Macaca fascicularis , Macrófagos/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones SCID , Membrana Mucosa/metabolismo , Ratas , Ratas Wistar , Transcitosis/fisiologíaRESUMEN
Due to the prevailing existence of the COVID-19 pandemic, novel and practical strategies to combat pathogens are on the rise worldwide. It is estimated that, globally, around 10% of hospital patients will acquire at least one healthcare-associated infection. One of the novel strategies that has been developed is incorporating metallic particles into polymeric materials that neutralize infectious agents. Considering the broad-spectrum antimicrobial potency of some materials, the incorporation of metallic particles into the intended hybrid composite material could inherently add significant value to the final product. Therefore, this research aimed to investigate an antimicrobial polymeric PLA-based composite material enhanced with different microparticles (copper, aluminum, stainless steel, and bronze) for the antimicrobial properties of the hybrid composite. The prepared composite material samples produced with fused filament fabrication (FFF) 3D printing technology were tested for different time intervals to establish their antimicrobial activities. The results presented here depict that the sample prepared with 90% copper and 10% PLA showed the best antibacterial activity (99.5%) after just 20 min against different types of bacteria as compared to the other samples. The metallic-enriched PLA-based antibacterial sheets were remarkably effective against Staphylococcus aureus and Escherichia coli; therefore, they can be a good candidate for future biomedical, food packaging, tissue engineering, prosthetic material, textile industry, and other science and technology applications. Thus, antimicrobial sheets made from PLA mixed with metallic particles offer sustainable solutions for a wide range of applications where touching surfaces is a big concern.
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Antiinfecciosos , Tratamiento Farmacológico de COVID-19 , Aluminio , Antibacterianos/farmacología , Antiinfecciosos/farmacología , Cobre , Escherichia coli , Humanos , Pandemias , Poliésteres , Polímeros , Impresión Tridimensional , Acero InoxidableRESUMEN
To understand the reasons of successful spread of carbapenem-resistant Klebsiella pneumoniae ST14 (CRKP-ST14) in countries of the Arabian Peninsula, the resistome, capsular locus, carbapenemase carrying plasmid types, and core genome of isolates from the region were compared to global isolates. Thirty-nine CRKP-ST14 strains isolated from 13 hospitals in the United Arab Emirates, Bahrain, and Saudi Arabia were selected for whole genome sequencing on Illumina MiSeq platform based on the variety of carbapenemase genes carried and plasmids bearing these genes. Their resistome, capsular locus, and core genome MLST were compared to 173 CRKP-ST14 genomes available in public databases. The selected 39 CRKP-ST14 produced either NDM-1, OXA-48, OXA-162, OXA-232, KPC-2, or co-produced NDM-1 and an OXA-48-like carbapenemase. cgMLST revealed three clusters: 16 isolates from five UAE cities (C1), 11 isolates from three UAE cities and Bahrain (C2), and 5 isolates from Saudi Arabia (C3), respectively, and seven singletons. Resistance gene profile, carbapenemase genes, and their plasmid types were variable in both C1 and C2 clusters. The majority of CRKP-ST14 had KL2, but members of the C2 cluster and two further singletons possessed KL64 capsular locus. Based on cgMLST comparison of regional and global isolates, CRKP-ST14 with KL64 from four continents formed a distinct cluster, suggesting a recent emergence and spread of this variant. Our findings confirmed clonal transmission coupled with likely horizontal gene transfer in carbapenem-resistant Klebsiella pneumoniae ST14. Dissemination of this genetically flexible, highly resistant clone warrants further monitoring.
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Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus responsible for the coronavirus disease (COVID-19) pandemic, is sweeping the world today. This study investigates the optical detection of SARS-CoV-2, utilizing the antigen-antibody binding interactions utilizing a light source from a smart phone and a portable spectrophotometer. The proof-of-concept is shown by detecting soluble preparations of spike protein subunits from SARS-CoV-2, followed by detection of the actual binding potential of the SARS-CoV-2 proteins with their corresponding antigens. The measured binding interactions for RBD and NCP proteins with their corresponding antibodies under different conditions have been measured and analyzed. Based on these observations, a "hump or spike" in light intensity is observed when a specific molecular interaction takes place between two proteins. The optical responses could further be analyzed using the principle component analysis technique to enhance and allows precise detection of the specific target in a multi-protein mixture.
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COVID-19 , Glicoproteína de la Espiga del Coronavirus , Anticuerpos Antivirales , Humanos , SARS-CoV-2RESUMEN
BACKGROUND AND PURPOSE: Data from randomly controlled trials have indicated that a decompressive hemicraniectomy is more clinically effective than medical treatment in the management of space-occupying brain oedema post middle cerebral artery infarction. This economic evaluation compares the impact of the two options in the UK. No recent study has conducted an economic evaluation on this topic for the UK. METHOD: A cost-utility analysis over a time period of 1 year was used, measuring benefits in terms of quality adjusted life years (QALYs) and costs in pound sterling, discounted to 2015 prices. The evaluation was from the perspective of the National Health Service, the largest healthcare provider in the UK. RESULTS: The cost-utility analysis found an incremental cost effectiveness of £116 595.10 for every QALY gained if patients were offered a decompressive hemicraniectomy compared to the best medical treatment. DISCUSSION: This is above the National Institute for Health and Care Excellence (NICE) 'cost-effective' threshold of £20 000-£30 000 per QALY, but lower mortality rates associated with the surgical alternative raises ethical considerations for healthcare providers in the UK.
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Edema Encefálico/cirugía , Craneotomía/economía , Infarto de la Arteria Cerebral Media/cirugía , Análisis Costo-Beneficio , Craneotomía/métodos , Femenino , Humanos , Masculino , Años de Vida Ajustados por Calidad de Vida , Resultado del TratamientoRESUMEN
The Mason-Pfizer monkey virus (MPMV) genomic RNA (gRNA) packaging signal is a highly-structured element with several stem-loops held together by two phylogenetically conserved long-range interactions (LRIs) between U5 and gag complementary sequences. These LRIs play a critical role in maintaining the structure of the 5´ end of the MPMV gRNA. Thus, one could hypothesize that the overall RNA secondary structure of this region is further architecturally held together by three other stem loops (SL3, Gag SL1, and Gag SL2) comprising of sequences from the distal parts of the 5´untranslated region (5' UTR) to ~ 120 nucleotides into gag, excluding gag sequences involved in forming the U5-Gag LRIs. To provide functional evidence for the biological significance of these stem loops during gRNA encapsidation, these structural motifs were mutated and their effects on MPMV RNA packaging and propagation were tested in a single round trans-complementation assay. The mutant RNA structures were further studied by high throughput SHAPE (hSHAPE) assay. Our results reveal that sequences involved in forming these three stem loops do not play crucial roles at an individual level during MPMV gRNA packaging or propagation. Further structure-function analysis indicates that the U5-Gag LRIs have a more important architectural role in stabilizing the higher order structure of the 5´ UTR than the three stem loops which have a more secondary and perhaps indirect role in stabilizing the overall RNA secondary structure of the region. Our work provides a better understanding of the molecular interactions that take place during MPMV gRNA packaging.
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Productos del Gen gag/genética , Virus del Mono Mason-Pfizer/fisiología , ARN Viral/química , ARN Viral/genética , Regiones no Traducidas 5' , Productos del Gen gag/química , Humanos , Virus del Mono Mason-Pfizer/genética , Modelos Moleculares , Mutación , Conformación de Ácido Nucleico , Estabilidad del ARN , Ensamble de VirusRESUMEN
We discuss the case and differential diagnoses of an elderly man who presented with bilateral facial palsy. He had injured his forehead in the garden during a fall on his face and the open wound was contaminated by soil. He then presented to the emergency department with facial weakness causing difficulty speaking. The penny dropped when he started developing muscle spasms affecting his lower jaw a day after admission. It also became clear that he could not open his mouth wide (lock jaw). The combination of muscle spasms and lock jaw (trismus) made tetanus the most likely possibility, and this was proven when he had samples taken from his wound and analysed under the microscope, which showed Clostridium tetani bacilli. C. tetani spores are widespread in the environment, including in the soil, and can survive hostile conditions for long periods of time. Transmission occurs when spores are introduced into the body, often through contaminated wounds. Tetanus in the United Kingdom is rare, but can prove fatal if there is a delay in recognition and treatment.
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Clostridium tetani , Parálisis Facial/diagnóstico , Tétanos/diagnóstico , Anciano , Diagnóstico Diferencial , Parálisis Facial/microbiología , Humanos , Masculino , Tétanos/complicacionesRESUMEN
MPMV has great potential for development as a vector for gene therapy. In this respect, precisely defining the sequences and structural motifs that are important for dimerization and packaging of its genomic RNA (gRNA) are of utmost importance. A distinguishing feature of the MPMV gRNA packaging signal is two phylogenetically conserved long-range interactions (LRIs) between U5 and gag complementary sequences, LRI-I and LRI-II. To test their biological significance in the MPMV life cycle, we introduced mutations into these structural motifs and tested their effects on MPMV gRNA packaging and propagation. Furthermore, we probed the structure of key mutants using SHAPE (selective 2'hydroxyl acylation analyzed by primer extension). Disrupting base-pairing of the LRIs affected gRNA packaging and propagation, demonstrating their significance to the MPMV life cycle. A double mutant restoring a heterologous LRI-I was fully functional, whereas a similar LRI-II mutant failed to restore gRNA packaging and propagation. These results demonstrate that while LRI-I acts at the structural level, maintaining base-pairing is not sufficient for LRI-II function. In addition, in vitro RNA dimerization assays indicated that the loss of RNA packaging in LRI mutants could not be attributed to the defects in dimerization. Our findings suggest that U5-gag LRIs play an important architectural role in maintaining the structure of the 5' region of the MPMV gRNA, expanding the crucial role of LRIs to the nonlentiviral group of retroviruses.
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Genes gag , Virus del Mono Mason-Pfizer/genética , ARN Viral/genética , Ensamble de VirusRESUMEN
Packaging the mouse mammary tumor virus (MMTV) genomic RNA (gRNA) requires the entire 5' untranslated region (UTR) in conjunction with the first 120 nucleotides of the gag gene. This region includes several palindromic (pal) sequence(s) and stable stem loops (SLs). Among these, stem loop 4 (SL4) adopts a bifurcated structure consisting of three stems, two apical loops, and an internal loop. Pal II, located in one of the apical loops, mediates gRNA dimerization, a process intricately linked to packaging. We thus hypothesized that the bifurcated SL4 structure could constitute the major gRNA packaging determinant. To test this hypothesis, the two apical loops and the flanking sequences forming the bifurcated SL4 were individually mutated. These mutations all had deleterious effects on gRNA packaging and propagation. Next, single and compensatory mutants were designed to destabilize then recreate the bifurcated SL4 structure. A structure-function analysis using bioinformatics predictions and RNA chemical probing revealed that mutations that led to the loss of the SL4 bifurcated structure abrogated RNA packaging and propagation, while compensatory mutations that recreated the native SL4 structure restored RNA packaging and propagation to wild type levels. Altogether, our results demonstrate that SL4 constitutes the principal packaging determinant of MMTV gRNA. Our findings further suggest that SL4 acts as a structural switch that can not only differentiate between RNA for translation versus packaging/dimerization, but its location also allows differentiation between spliced and unspliced RNAs during gRNA encapsidation.
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Dimerización , Virus del Tumor Mamario del Ratón/metabolismo , Biosíntesis de Proteínas , ARN Viral/química , ARN Viral/metabolismo , Ensamble de Virus , Animales , Genómica , Virus del Tumor Mamario del Ratón/química , Virus del Tumor Mamario del Ratón/genética , Ratones , Conformación de Ácido Nucleico , ARN Viral/genéticaRESUMEN
OBJECTIVE: This article examines the trends in morbidities and healthcare utilisation in Malaysian older people aged 60 years and above. STUDY DESIGN: This is a repeated cross-sectional study. METHODS: Data from three nation-wide community-based surveys, which were conducted in 1996, 2006, and 2015 were analysed. Multivariate analysis was performed for 2015 data to identify factors associated with healthcare utilisation. RESULTS: Analysis noted increasing trends in the prevalence of diabetes, hypertension, hypercholesterolaemia and obesity from 1996 to 2015. Decreasing trends were noted in the prevalence of current smokers and drinkers over this 20-year period, whereas health service utilisation increased with age in all surveys. In 2015, both inpatient and outpatient care are significantly associated with increasing age and diabetes. CONCLUSIONS: Increasing trends of health problems and healthcare utilisation were observed among older people in Malaysia. Policymakers should plan for appropriate resources to meet the challenges of an ageing population in Malaysia.
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Morbilidad/tendencias , Aceptación de la Atención de Salud/estadística & datos numéricos , Anciano , Estudios Transversales , Femenino , Encuestas de Atención de la Salud , Humanos , Malasia/epidemiología , Masculino , Persona de Mediana EdadRESUMEN
The infected non union of the long bones in the presence of the intramedullary nail is a dreaded complication of fracture management. Around 7% patients may develop an infected non union of the long bones in intramedullary nailing. Amongst the various grades of infection, grade three infection is the most difficult to cure and manage as it involves an osteomyelitic bone. Amongst an array of therapeutic modalities, the two stage methods are commonly used with the first stage aimed at controlling the infection and the second stage at inducing union. This increases the number of surgical procedures. We used an Ilizarov threaded rod coated with antibiotic impregnated cement to replace the intramedullary nail with the idea of delivering higher concentration of antibiotic locally as well as provide stability. We achieved a union rate of 91% in a relatively small number of patients with this single procedure. The antibiotic impregnated cement coated Ilizarov rod that we used in our study achieves both infection control and union simultaneously and does not allow cement debonding at removal.
Asunto(s)
Antibacterianos/administración & dosificación , Infecciones Bacterianas/tratamiento farmacológico , Cementos para Huesos , Enfermedades Óseas/tratamiento farmacológico , Enfermedades Óseas/microbiología , Clavos Ortopédicos , Materiales Biocompatibles Revestidos , Fracturas del Fémur/cirugía , Fracturas no Consolidadas/cirugía , Fracturas de la Tibia/cirugía , Adulto , Infecciones Bacterianas/etiología , Fracturas del Fémur/complicaciones , Fracturas no Consolidadas/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Diseño de Prótesis , Fracturas de la Tibia/complicaciones , Adulto JovenRESUMEN
BACKGROUND: As the field of Primary Aldosteronism (PA) becomes ever expanded, diagnosis of PA is increasingly diagnosed by endocrinologists. With increased PA screening, many of the cases are now found in patients with complex co-morbidities in addition to their hypertension. Post adrenalectomy renal impairment with hyperkalemia is now increasingly seen in these complex patients, as evidenced by the numerous reports on this issue that have appeared within the past 3 years. We present a small case series to illustrate the breadth of the problem, along with a discussion about how such CKD/hyperkalemic events may be predicted. CASE PRESENTATION: We present three cases of primary aldosteronism with long standing hypertension (more than 10 years) hypokalemia (2.0-3.0 mmol/l). Serum aldosterone was high with low renin activity leading to high aldosterone to renin ratio (ARR). They underwent abdominal CT scan revealing adrenal mass and adrenal vein sample confirmed lateralization. None of the patients had evidence of renal disease before surgery (as evident by normal eGFR and serum creatinine). Post adrenalectomy they had reduction in the blood pressure and became eukalemic. Serum aldosterone and renin activity were low leading to a low ARR. Case 1 developed hyperkalemia and increased serum creatinine 6 weeks post operatively which resolved with initiation of fludrocortisone and every attempt to discontinue fludrocortisone resulted in hyperkalemia and rising creatinine. Her hyperkalemia is under control with oral sodium bicarbonate. Case 2 developed hyperkalemia and increasing creatinine 2 months post operatively transiently requiring fludrocortisone and later on managed with furosemide for hyperkalemia. Case 3 developed renal impairment and hyperkalemia 2 weeks post operatively requiring fludrocortisone. CONCLUSION: Post APA resection severe hyperkalemia may be a common entity and screening should be actively considered in high risk patients. Older age, longer duration of hypertension, impaired pre-op and post-op GFR and higher levels of pre-op aldosterone and are all risk factors which predict the likelihood of developing post-operative hyperkalemia. Fludrocortisone, sodium bicarbonate, loop diuretics and potassium binders can be used for treatment. Treatment choice should be tailored to patient characteristics including fluid status, blood pressure and serum creatinine. Potassium binders should be avoided in patients with history of recent abdominal surgery, opioid use and constipation. Serum electrolytes and creatinine should be monitored every 1-2 weeks after starting treatment to ensure an adequate response. Prolonged management may be necessary in some cases and at-risk patients should be counselled as to the meaning and importance of post-operative changes in measured renal function and potassium.