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1.
J Mol Biol ; 436(16): 168693, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38960133

RESUMEN

Septins are filamentous nucleotide-binding proteins which can associate with membranes in a curvature-dependent manner leading to structural remodelling and barrier formation. Ciona intestinalis, a model for exploring the development and evolution of the chordate lineage, has only four septin-coding genes within its genome. These represent orthologues of the four classical mammalian subgroups, making it a minimalist non-redundant model for studying the modular assembly of septins into linear oligomers and thereby filamentous polymers. Here, we show that C. intestinalis septins present a similar biochemistry to their human orthologues and also provide the cryo-EM structures of an octamer, a hexamer and a tetrameric sub-complex. The octamer, which has the canonical arrangement (2-6-7-9-9-7-6-2) clearly shows an exposed NC-interface at its termini enabling copolymerization with hexamers into mixed filaments. Indeed, only combinations of septins which had CiSEPT2 occupying the terminal position were able to assemble into filaments via NC-interface association. The CiSEPT7-CiSEPT9 tetramer is the smallest septin particle to be solved by Cryo-EM to date and its good resolution (2.7 Å) provides a well-defined view of the central NC-interface. On the other hand, the CiSEPT7-CiSEPT9 G-interface shows signs of fragility permitting toggling between hexamers and octamers, similar to that seen in human septins but not in yeast. The new structures provide insights concerning the molecular mechanism for cross-talk between adjacent interfaces. This indicates that C. intestinalis may represent a valuable tool for future studies, fulfilling the requirements of a complete but simpler system to understand the mechanisms behind the assembly and dynamics of septin filaments.

2.
Parasitol Int ; : 102937, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39059482

RESUMEN

Guinea fowls, Numida meleagris (L., 1758), are galliform birds native to sub-Saharan Africa, but introduced in several countries around the world for domestic breeding and/or animal production. This species is considered more resistant to disease by Eimeria spp. than other domestic galliform birds. Here we review the Eimeria spp. known to infect species of Numididae and provide the first molecular identification of an Eimeria sp. from Guinea fowls. There are currently 3 named eimerians from Guinea fowls; Eimeria numidae Pellerdy, 1962; Eimeria grenieri Yvoré and Aycardi, 1967; and Eimeria gorakhpuri Bhatia & Pande, 1967. We reviewed each of these species descriptions and documented their taxonomic shortcomings. From that, we suggest that E. gorakhpuri is a junior synonym of E. numidae. In conclusion, we have morphologically redescribed in detail E. grenieri from N. meleagris from Rio de Janeiro and provided molecular supplementation through sequencing of three non-overlapping loci in cox1 and cox3 genes and fragments of small and large subunit mitochondrial rDNA.

3.
Adv Sci (Weinh) ; : e2400540, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39010670

RESUMEN

The growing prevalence of Internet of Things (IoT) devices hinges on resolving the challenge of powering sensors and transmitters. Addressing this, supply-less IoT devices are gaining traction by integrating energy harvesters. This study introduces a temperature sensor devoid of external power sources, achieved through a novel luminescent solar concentrator (LSC) device based on a stretchable, adhesive elastomer. Leveraging a lanthanide-doped styrene-ethylene-butylene-styrene matrix, the LSC yielded 0.09% device efficiency. The resultant temperature sensor exhibits a thermal sensitivity of 2.1%°C-1 and a 0.06 °C temperature uncertainty, autonomously transmitting real-time data to a server for user visualization via smartphones. Additionally, the integration of LED-based lighting enables functionality in low-light conditions, ensuring 24 h cycle operation and the possibility of having four distinct thermometric parameters without changing the device configuration, stating remarkable robustness and reliability of the system.

4.
Artículo en Inglés | MEDLINE | ID: mdl-39010786

RESUMEN

OBJECTIVES: Ineffective esophageal motility (IEM) on high-resolution manometry (HRM) is not consistently associated with specific clinical syndromes or outcomes. We evaluated the prevalence, clinical features, management, and outcomes of pediatric IEM patients across the United States. METHODS: Clinical and manometric characteristics of children undergoing esophageal HRM during 2021-2022 were collected from 12 pediatric motility centers. Clinical presentation, test results, management strategies, and outcomes were compared between children with IEM and normal HRM. RESULTS: Of 236 children (median age 15 years, 63.6% female, 79.2% Caucasian), 62 (23.6%) patients had IEM, and 174 (73.7%) patients had normal HRM, with similar demographics, medical history, clinical presentation, and median symptom duration. Reflux monitoring was performed more often for IEM patients (25.8% vs. 8.6%, p = 0.002), but other adjunctive testing was similar. Among 101 patients with follow-up, symptomatic cohorts declined in both groups in relation to the initial presentation (p > 0.107 for each comparison) with management targeting symptoms, particularly acid suppression. Though prokinetics were used more often and behavioral therapy less often in IEM (p ≤ 0.015 for each comparison), symptom outcomes were similar between IEM and normal HRM. Despite a higher proportion with residual dysphagia on follow-up in IEM (64.0% vs. 39.1%, p = 0.043), an alternate mechanism for dysphagia was identified more often in IEM (68.8%) compared to normal HRM (27.8%, p = 0.017). CONCLUSIONS: IEM is a descriptive manometric pattern rather than a clinical diagnosis requiring specific intervention in children. Management based on clinical presentation provides consistent symptom outcomes.

5.
J Appl Crystallogr ; 57(Pt 3): 865-876, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38846771

RESUMEN

Three-dimensional cryo electron microscopy reconstructions are obtained by extracting information from a large number of projections of the object. These projections correspond to different 'views' or 'orientations', i.e. directions in which these projections show the reconstructed object. Uneven distribution of these views and the presence of dominating preferred orientations may distort the reconstructed spatial images. This work describes the program VUE (views on uniform grids for cryo electron microscopy), designed to study such distributions. Its algorithms, based on uniform virtual grids on a sphere, allow an easy calculation and accurate quantitative analysis of the frequency distribution of the views. The key computational element is the Lambert azimuthal equal-area projection of a spherical uniform grid onto a disc. This projection keeps the surface area constant and represents the frequency distribution with no visual bias. Since it has multiple tunable parameters, the program is easily adaptable to individual needs, and to the features of a particular project or of the figure to be produced. It can help identify problems related to an uneven distribution of views. Optionally, it can modify the list of projections, distributing the views more uniformly. The program can also be used as a teaching tool.

6.
J Am Coll Radiol ; 21(6S): S100-S125, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38823940

RESUMEN

Diagnostic evaluation of a patient with dizziness or vertigo is complicated by a lack of standardized nomenclature, significant overlap in symptom descriptions, and the subjective nature of the patient's symptoms. Although dizziness is an imprecise term often used by patients to describe a feeling of being off-balance, in many cases dizziness can be subcategorized based on symptomatology as vertigo (false sense of motion or spinning), disequilibrium (imbalance with gait instability), presyncope (nearly fainting or blacking out), or lightheadedness (nonspecific). As such, current diagnostic paradigms focus on timing, triggers, and associated symptoms rather than subjective descriptions of dizziness type. Regardless, these factors complicate the selection of appropriate diagnostic imaging in patients presenting with dizziness or vertigo. This document serves to aid providers in this selection by using a framework of definable clinical variants. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.


Asunto(s)
Mareo , Sociedades Médicas , Mareo/diagnóstico por imagen , Humanos , Estados Unidos , Ataxia/diagnóstico por imagen , Medicina Basada en la Evidencia , Diagnóstico Diferencial
7.
J Am Coll Radiol ; 21(6S): S21-S64, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38823945

RESUMEN

Cerebrovascular disease encompasses a vast array of conditions. The imaging recommendations for stroke-related conditions involving noninflammatory steno-occlusive arterial and venous cerebrovascular disease including carotid stenosis, carotid dissection, intracranial large vessel occlusion, and cerebral venous sinus thrombosis are encompassed by this document. Additional imaging recommendations regarding complications of these conditions including intraparenchymal hemorrhage and completed ischemic strokes are also discussed. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.


Asunto(s)
Medicina Basada en la Evidencia , Sociedades Médicas , Accidente Cerebrovascular , Humanos , Accidente Cerebrovascular/diagnóstico por imagen , Estados Unidos , Trastornos Cerebrovasculares/diagnóstico por imagen
8.
Dalton Trans ; 53(25): 10655-10665, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38860528

RESUMEN

Here we describe the synthesis of a compositional series of metal-organic framework crystalline-inorganic glass composites (MOF-CIGCs) containing ZIF-8 and an inorganic phosphate glass, 20Na2O-10NaCl-70P2O5, to expand the library of host matrices for metal-organic frameworks. By careful selection of the inorganic glass component, a relatively high loading of ZIF-8 (70 wt%) was achieved, which is the active component of the composite. A Zn⋯O-P interfacial bond, previously identified in similar composites/hybrid blends, was suggested by analysis of the total scattering pair distribution function data. Additionally, CO2 and N2 sorption and variable-temperature PXRD experiments were performed to assess the composites' properties.

9.
Nat Struct Mol Biol ; 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38844527

RESUMEN

The ribosomal RNA of the human protein synthesis machinery comprises numerous chemical modifications that are introduced during ribosome biogenesis. Here we present the 1.9 Å resolution cryo electron microscopy structure of the 80S human ribosome resolving numerous new ribosomal RNA modifications and functionally important ions such as Zn2+, K+ and Mg2+, including their associated individual water molecules. The 2'-O-methylation, pseudo-uridine and base modifications were confirmed by mass spectrometry, resulting in a complete investigation of the >230 sites, many of which could not be addressed previously. They choreograph key interactions within the RNA and at the interface with proteins, including at the ribosomal subunit interfaces of the fully assembled 80S ribosome. Uridine isomerization turns out to be a key mechanism for U-A base pair stabilization in RNA in general. The structural environment of chemical modifications and ions is primordial for the RNA architecture of the mature human ribosome, hence providing a structural framework to address their role in healthy states and in human diseases.

10.
J Endod ; 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38815857

RESUMEN

INTRODUCTION: To evaluate the antimicrobial activity of Triton irrigation versus 4% sodium hypochlorite (NaOCl) utilizing a direct contact test and an extracted tooth model. METHODS: In the first experiment, a direct contact test was conducted to compare bacterial DNA removal and microbial diversity changes following irrigation with 4% NaOCl or Triton. Hydroxyapatite and dentin discs were inoculated with subgingival human-derived dental plaque for 2 weeks utilizing the Center for Disease Control biofilm reactor and subsequently challenged with the root canal irrigants for 5 minutes. In the second experiment, teeth contaminated with a multispecies biofilm (n = 24) were assigned into two treatment groups, NaOCl or Triton irrigation. Samples were obtained for quantitative real-time polymerase chain reaction and next-generation sequencing analysis before and after instrumentation. The Shannon and Chao1 indices were used to measure alpha diversity. The Bray-Curtis dissimilarity and ANOSIM was used to measure beta diversity. Differences in abundances of genera were evaluated using Kruskal-Wallis test with Bonferroni corrections. RESULTS: The direct contact test revealed no significant differences in the bacterial load based on 16S rRNA gene molecules/µL, reads, or differences in the Shannon index among groups. In the extracted tooth model, a bacterial load reduction of log10 3.08 ± 0.69 and 2.76 ± 0.91 were found for NaOCl and Triton, respectively (P = .348). Next-generation sequencing showed fewer reads, lower Chao1, and beta diversity values when pretreatment and post-treatment samples were assessed in both experimental groups (P < .0001). The Kruskal-Wallis analysis found that 17 genera of bacteria were over-represented in minimal values in the Triton post-treatment group, 14 of these genera represented less than 1% of the microbial community. CONCLUSIONS: Both irrigants had limited antimicrobial activity in the direct contact test. When used in conjunction with mechanical instrumentation both irrigants were able to reduce the bacterial DNA load and diversity in comparison with pretreatment communities. The NaOCl irrigation, followed by ethylenediaminetetraacetic acid flush, was more effective in decreasing DNA counts from low-abundance organisms.

11.
Childs Nerv Syst ; 40(8): 2527-2534, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38777910

RESUMEN

PURPOSE: Chiari I malformation (CM-I) in pediatric patients can impose substantial neurologic and functional impairment. Additionally, the presence of syrinx is often a harbinger of clinical compromise, but little attention has been devoted to identifying features associated with syrinx development and the clinical impact of syrinx resolution. Therefore, this study aims to identify clinical and radiographic variables associated with preoperative syrinx presence and postoperative syrinx reduction in pediatric patients with CM-I and determine the relationship between postoperative syrinx reduction and clinical symptom improvement. METHODS: The authors performed a retrospective analysis of 435 consecutive pediatric patients who underwent surgical treatment of CM-I from 2001 to 2021 at a single tertiary pediatric medical center. All patients underwent pre- and postoperative MRI, and clinical and radiographic variables were recorded and subject to inferential analysis. RESULTS: Syrinx at presentation was independently associated with symptoms of spinal cord dysfunction at presentation (OR 2.17 (95% CI 1.05-4.48); p = 0.036), scoliosis (OR 5.33 (2.34-10.86); p = 0.001), and greater pB-C2 (posterior basion to C2 distance) measurement length (OR 1.14 (95% CI 1.01-1.30); p = 0.040). Syrinx at presentation was inversely associated with tussive headaches at presentation (OR 0.27 (95% CI 0.16-0.47); p = 0.001) and cranial nerve deficits at presentation (OR 0.49 (95% CI 0.26-0.92); p = 0.025). Postoperatively, patients with radiographic evidence of syrinx improvement had greater rates of symptom improvement (93.1% vs 82.1%; p = 0.049), better CCOS scores (15.4 vs 14.2; p = 0.001), and decreased rates of readmission (6.0% vs 25.0%, p = 0.002) and reoperation (0.5% vs 35.7%; p = 0.001). The difference in syrinx resolution was similar but not statistically significant (10.3% vs 16.7%; p = 0.251). AO joint anomaly (OR 0.20, 95% CI 0.04-0.95; p = 0.026) and foramen magnum diameter (OR 1.12, 95% CI 1.00-1.25; p = 0.049) were the only independent predictors of syrinx improvement, and surgical technique was the only predictor for syrinx resolution (OR 2.44, 95% CI 1.08-5.50; p = 0.031). Patients that underwent tonsil reduction surgery whose syrinx improved had a wider foramen magnum diameter than those whose did not improve (34.3 vs 31.7; p = 0.028). CONCLUSIONS: Radiographic syrinx improvement is associated with greater rates of symptom improvement and less readmissions and reoperations for CM-I. AO joint anomalies and narrower foramen magnums were independent risk factors for the lack of syrinx improvement. These novel insights will help guide preoperative patient counseling, pre- and intraoperative surgical decision-making, and postoperative clinical prognostication in the treatment of pediatric CM-I.


Asunto(s)
Malformación de Arnold-Chiari , Siringomielia , Humanos , Malformación de Arnold-Chiari/cirugía , Malformación de Arnold-Chiari/diagnóstico por imagen , Malformación de Arnold-Chiari/complicaciones , Masculino , Femenino , Siringomielia/cirugía , Siringomielia/diagnóstico por imagen , Niño , Estudios Retrospectivos , Adolescente , Preescolar , Resultado del Tratamiento , Imagen por Resonancia Magnética , Lactante
12.
Brain Behav Immun ; 120: 248-255, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38795783

RESUMEN

Major depressive disorder (MDD) is associated with Alzheimer's disease (AD) but the precise mechanisms underlying this relationship are not understood. While it is well established that cerebrospinal fluid (CSF) soluble levels of triggering receptor expressed on myeloid cells 2 (sTREM2) increase during early stages of AD, how sTREM2 levels behave in subjects with MDD is not known. In a longitudinal study, we measured CSF sTREM2 levels in 27 elderly cognitively intact individuals with late-life major depression (LLMD) and in 19 healthy controls. We tested the hypothesis that, similarly to what happens in early stages of AD, CSF sTREM2 would be elevated in MDD. In addition, we compared the associations of CSF sTREM2, pro- and anti- inflammatory, and AD biomarkers in LLMD and control subjects. Surprisingly, we found that mean CSF sTREM2 levels were significantly reduced in LLMD compared to controls. This reduction was no longer significant at the 3-year follow-up visit when depression severity improved. In addition, we found that CSF sTREM2 was associated with AD biomarkers and proinflammatory cytokines in controls but not in LLMD. These findings suggest that impaired microglia phagocytic response to AD pathology may be a novel link between MDD and AD.


Asunto(s)
Enfermedad de Alzheimer , Biomarcadores , Trastorno Depresivo Mayor , Glicoproteínas de Membrana , Microglía , Receptores Inmunológicos , Humanos , Trastorno Depresivo Mayor/metabolismo , Trastorno Depresivo Mayor/líquido cefalorraquídeo , Masculino , Microglía/metabolismo , Femenino , Anciano , Receptores Inmunológicos/metabolismo , Glicoproteínas de Membrana/líquido cefalorraquídeo , Glicoproteínas de Membrana/metabolismo , Enfermedad de Alzheimer/líquido cefalorraquídeo , Enfermedad de Alzheimer/metabolismo , Biomarcadores/líquido cefalorraquídeo , Estudios Longitudinales , Fagocitosis/fisiología , Citocinas/metabolismo , Citocinas/líquido cefalorraquídeo , Persona de Mediana Edad , Anciano de 80 o más Años , Inflamación/metabolismo , Inflamación/líquido cefalorraquídeo
13.
J Sport Health Sci ; 13(5): 631-641, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38735532

RESUMEN

BACKGROUND: Optimal patterns of accrual of recommended levels of physical activity (PA) for prevention of hypertension and obesity are not known. The overall aim of this study was to investigate whether different patterns of accumulation of PA are differentially associated with hypertension and obesity in Australian women over 21 years. Specifically, we investigated whether, for the same weekly volume of PA, the number of sessions (frequency) and vigorousness of PA (intensity) were associated with a reduction in the occurrence of hypertension and obesity in women. METHODS: Data from the 1973-1978 and 1946-1951 cohorts of the Australian Longitudinal Study on Women's Health were analyzed (n = 20,588; 12%-16% with a Bachelor's or higher degree). Self-reported PA, hypertension, height, and weight were collected using mail surveys every 3 years from 1998/2000 to 2019/2021. Generalized Estimating Equation models with a 3-year lag model were used to investigate the association of PA volume (metabolic equivalent min/week) (none; 33-499; 500-999; ≥1000, weekly frequency (none; 1-2 times; 3-4 times; 5-7 times; ≥8 times), and the proportion of vigorous PA to total volume of PA (none; 0%; 1%-33%; 34%-66%; 67%-100%) with odds of hypertension and obesity from 2000 to 2021. RESULTS: The cumulative incidence of hypertension was 6% in the 1973-1978 and 23% in the 1946-1951 cohort; 27% of women in the 1973-1978; and 15% in the 1946-1951 cohort developed obesity over the period. Overall, a higher volume of PA was associated with reduced odds of hypertension and obesity. When the volume of PA was considered, the odds of hypertension did not vary according to the frequency or intensity of PA. However, increased proportion of vigorous PA to the total volume of PA was associated with a small additional reduction in the risk of obesity. CONCLUSION: PA volume appears to be more important than the pattern of accumulation for the prevention of hypertension and obesity. Incorporating more sessions, particularly of vigorous-intensity PA, may provide extra benefits for the prevention of obesity.


Asunto(s)
Ejercicio Físico , Hipertensión , Obesidad , Humanos , Femenino , Hipertensión/epidemiología , Hipertensión/prevención & control , Obesidad/epidemiología , Obesidad/prevención & control , Australia/epidemiología , Estudios Longitudinales , Persona de Mediana Edad , Adulto , Anciano
14.
J Natl Compr Canc Netw ; 22(2D)2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38729204

RESUMEN

BACKGROUND: The prevalence of chronic hepatitis C virus (HCV) infection in the United States is ≤1%. Universal HCV screening is recommended nationwide. Here we describe our experience implementing universal HCV screening at a cancer center. METHODS: In October 2016, universal HCV screening with HCV antibody (anti-HCV) was initiated for all new outpatients. Universal screening was promoted through widespread provider education, orders in the Epic electronic health records (EHRs), SmartSets, and automated EHR reminders. The effort focused on patients with solid tumors, because universal screening in patients with hematologic malignancies was already standard practice. Primary outcomes were the proportion of patients screened and the proportion of patients with reactive anti-HCV test results linked to HCV care. The secondary outcome was the incidence of HCV-associated hepatocellular carcinoma as a second primary malignancy (HCC-SPM) in patients with a history of other cancers before HCC diagnosis. Epic's Reporting Workbench Business Intelligence tools were used. Statistical significance was defined as P<.05 on chi-square analysis. RESULTS: From April 2016 through April 2023, 56,075 patients with solid tumors were screened for HCV, of whom 1,300 (2.3%) had reactive anti-HCV test results. The proportion of patients screened was 10.1% in the 6 months before study implementation and 34.4% in the last 6 months of the study (P<.001). HCV screening was ordered using SmartSets in 39,332 (45.8%) patients and in response to automated EHR reminders in 10,972 (12.8%) patients. Most patients with reactive anti-HCV test results were linked to care (765/1,300; 59%), most with proven HCV infection were treated (425/562; 76%), and most treated patients achieved sustained virologic response (414/425; 97%). The incidence of HCC-SPMs was 15% in historical controls treated from 2011 to 2017 and 5.7% following implementation of universal screening (P=.0002). CONCLUSIONS: Universal HCV screening can be successfully implemented in cancer hospitals using an EHR-based multipronged approach to eliminate HCV and prevent HCV-associated HCC-SPMs.


Asunto(s)
Tamizaje Masivo , Centros de Atención Terciaria , Humanos , Masculino , Tamizaje Masivo/métodos , Femenino , Persona de Mediana Edad , Hepacivirus/aislamiento & purificación , Hepacivirus/inmunología , Anciano , Hepatitis C Crónica/epidemiología , Hepatitis C Crónica/diagnóstico , Hepatitis C Crónica/virología , Hepatitis C Crónica/complicaciones , Hepatitis C/epidemiología , Hepatitis C/diagnóstico , Hepatitis C/virología , Anticuerpos contra la Hepatitis C/sangre , Neoplasias Hepáticas/epidemiología , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/virología , Incidencia , Carcinoma Hepatocelular/epidemiología , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/virología , Registros Electrónicos de Salud
17.
J Alzheimers Dis ; 99(3): 877-881, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38701151

RESUMEN

Three recent anti-amyloid-ß antibody trials for Alzheimer's disease reported similar effect sizes, used non-reactive saline as placebo, and showed large numbers of adverse events including imaging anomalies (ARIA) that correlate with cognitive changes. Conversely, all previous antibody trials were less reactive and pronounced ineffective. We argue that these observations point to unblinding bias, inflating apparent efficacy and thus altering the risk-benefit balance. Further, we highlight data demonstrating that beyond reducing amyloid, monoclonal antibodies increase monomeric amyloid-ß42 in cerebrospinal fluid, which may explain potential benefits. We should recalibrate the efficacy of these antibodies and devote more resources into strategies beyond removing amyloid.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides , Fragmentos de Péptidos , Humanos , Péptidos beta-Amiloides/líquido cefalorraquídeo , Enfermedad de Alzheimer/metabolismo , Fragmentos de Péptidos/líquido cefalorraquídeo , Medición de Riesgo , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Monoclonales Humanizados/farmacología , Anticuerpos Monoclonales/uso terapéutico
18.
Syst Parasitol ; 101(3): 40, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38739253

RESUMEN

A novel Eimeria Schneider, 1875 species is described from an Australian pied oystercatcher Haematopus longirostris Vieillot, in Western Australia. The pied oystercatcher was admitted to the Kanyana Wildlife Rehabilitation Centre (KWRC), Perth, Western Australia in a poor body condition, abrasion to its right hock and signs of partial delamination to its lower beak. Investigation into potential medical causes resulted in a faecal sample being collected and screened for gastrointestinal parasites. Unsporulated coccidian oocysts were initially observed in the faeces and identified as Eimeria upon sporulation. The sporulated oocysts (n = 20) are ellipsoidal, 20-21 × 12-13 µm in shape and have thick bi-layered walls which are c.2/3 of the total thickness. Micropyle is present, robust and protruding, and occasionally has a rounded polar body attached to the micropyle. Within the oocyst, a residuum, in addition, two to five polar granules are present. There are four ellipsoidal sporocysts 9-11 × 5-6 µm with flattened to half-moon shaped Stieda bodies. Sub-Stieda body and para-Stieda body are absent. The sporocysts contain sporocyst residuums composed of a few spherules scattered among the sporozoites. Within the sporozoites, anterior and posterior refractile bodies are present, but the nucleus is indiscernible. To further characterise the novel Eimeria species from H. longirostris, molecular analysis was conducted at the 18S ribosomal RNA locus, using PCR amplification and cloning. Two cloned sequences from the novel Eimeria were compared with those from other Eimeria spp. with the highest genetic similarity of 97.6% and 97.2% from Clone 1 and 2, respectively with Eimeria reichenowi (AB544308) from a hooded crane (Grus monacha Temminck) in Japan. Both sequences grouped in a clade with the Eimeria spp. isolated from wetland birds, which include Eimeria paludosa (KJ767187) from a dusky moorhen (Gallinula tenebrosa Gould) in Western Australia, Eimeria reichenowi (AB544308) and Eimeria gruis (AB544336) both from hooded cranes. Based on the morphological and molecular data, this Eimeria sp. is a new species of coccidian parasite and is named Eimeria haematopusi n. sp. after its host H. longirostris.


Asunto(s)
Eimeria , Filogenia , ARN Ribosómico 18S , Animales , Eimeria/genética , Eimeria/clasificación , ARN Ribosómico 18S/genética , Australia Occidental , Charadriiformes/parasitología , Heces/parasitología , Oocistos , Coccidiosis/parasitología , Coccidiosis/veterinaria , Especificidad de la Especie , Enfermedades de las Aves/parasitología , ADN Protozoario/genética
19.
Ageing Res Rev ; 96: 102290, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38580173

RESUMEN

Biomarkers that predict the clinical onset of Alzheimer's disease (AD) enable the identification of individuals in the early, preclinical stages of the disease. Detecting AD at this point may allow for more effective therapeutic interventions and optimized enrollment for clinical trials of novel drugs. The current biological diagnosis of AD is based on the AT(N) classification system with the measurement of brain deposition of amyloid-ß (Aß) ("A"), tau pathology ("T"), and neurodegeneration ("N"). Diagnostic cut-offs for Aß1-42, the Aß1-42/Aß1-40 ratio, tau and hyperphosphorylated-tau concentrations in cerebrospinal fluid have been defined and may support AD clinical diagnosis. Blood-based biomarkers of the AT(N) categories have been described in the AD continuum. Cross-sectional and longitudinal studies have shown that the combination of blood biomarkers tracking neuroaxonal injury (neurofilament light chain) and neuroinflammatory pathways (glial fibrillary acidic protein) enhance sensitivity and specificity of AD clinical diagnosis and improve the prediction of AD onset. However, no international accepted cut-offs have been identified for these blood biomarkers. A kit for blood Aß1-42/Aß1-40 is commercially available in the U.S.; however, it does not provide a diagnosis, but simply estimates the risk of developing AD. Although blood-based AD biomarkers have a great potential in the diagnostic work-up of AD, they are not ready for the routine clinical use.


Asunto(s)
Enfermedad de Alzheimer , Humanos , Enfermedad de Alzheimer/metabolismo , Proteínas tau , Estudios Transversales , Péptidos beta-Amiloides , Biomarcadores/líquido cefalorraquídeo
20.
J Cell Biol ; 223(7)2024 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-38652117

RESUMEN

Assembly of macromolecular complexes at correct cellular sites is crucial for cell function. Nuclear pore complexes (NPCs) are large cylindrical assemblies with eightfold rotational symmetry, built through hierarchical binding of nucleoporins (Nups) forming distinct subcomplexes. Here, we uncover a role of ubiquitin-associated protein 2-like (UBAP2L) in the assembly and stability of properly organized and functional NPCs at the intact nuclear envelope (NE) in human cells. UBAP2L localizes to the nuclear pores and facilitates the formation of the Y-complex, an essential scaffold component of the NPC, and its localization to the NE. UBAP2L promotes the interaction of the Y-complex with POM121 and Nup153, the critical upstream factors in a well-defined sequential order of Nups assembly onto NE during interphase. Timely localization of the cytoplasmic Nup transport factor fragile X-related protein 1 (FXR1) to the NE and its interaction with the Y-complex are likewise dependent on UBAP2L. Thus, this NPC biogenesis mechanism integrates the cytoplasmic and the nuclear NPC assembly signals and ensures efficient nuclear transport, adaptation to nutrient stress, and cellular proliferative capacity, highlighting the importance of NPC homeostasis at the intact NE.


Asunto(s)
Proteínas Portadoras , Membrana Nuclear , Poro Nuclear , Humanos , Transporte Activo de Núcleo Celular , Células HeLa , Homeostasis , Glicoproteínas de Membrana , Membrana Nuclear/metabolismo , Poro Nuclear/metabolismo , Proteínas de Complejo Poro Nuclear/metabolismo , Proteínas Portadoras/metabolismo
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