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1.
PLoS Biol ; 21(6): e3002144, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37289745

RESUMO

Hosts have evolved diverse strategies to respond to microbial infections, including the detection of pathogen-encoded proteases by inflammasome-forming sensors such as NLRP1 and CARD8. Here, we find that the 3CL protease (3CLpro) encoded by diverse coronaviruses, including Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), cleaves a rapidly evolving region of human CARD8 and activates a robust inflammasome response. CARD8 is required for cell death and the release of pro-inflammatory cytokines during SARS-CoV-2 infection. We further find that natural variation alters CARD8 sensing of 3CLpro, including 3CLpro-mediated antagonism rather than activation of megabat CARD8. Likewise, we find that a single nucleotide polymorphism (SNP) in humans reduces CARD8's ability to sense coronavirus 3CLpros and, instead, enables sensing of 3C proteases (3Cpro) from select picornaviruses. Our findings demonstrate that CARD8 is a broad sensor of viral protease activities and suggests that CARD8 diversity contributes to inter- and intraspecies variation in inflammasome-mediated viral sensing and immunopathology.


Assuntos
COVID-19 , Picornaviridae , Humanos , Inflamassomos/metabolismo , Picornaviridae/genética , Picornaviridae/metabolismo , SARS-CoV-2/metabolismo , Inibidores de Proteases , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Adaptadoras de Sinalização CARD/metabolismo
2.
Cryobiology ; 90: 75-82, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31401082

RESUMO

There is a clinical demand for efficient cryopreservation of cloned camel embryos with considerable logistic and economic advantage. Vitrification of in vivo derived embryos has been reported in camels, but there is no study on vitrification of cloned embryos. Moreover, whether characteristic differences between cloned and in vivo derived embryos imply different vitrification requirement is unresolved. Here, we compared survival, re-expansion and pregnancy rates of cloned embryos vitrified using two commercial vitrification kits (Cryotec and Kitazato), developed basically for human embryos, and a vitrification protocol developed for in vivo camel embryos (CVP). Cloned embryos responded dynamically to vitrification-warming steps in commercial kits, with a flat shrinkage in the final vitrification solution and a quick re-expansion to the original volume immediately after transferring to the isotonic warming solution. Contrarily, full shrinkage was not observed in CVP method, and majority of embryos were still collapsed post-warming. The immediate re-expansion was highly associated and predictive of higher survival and total cell number, and also better redox state of embryos vitrified by Cryotec and Kitazato kits compared to CVP method. Importantly, while 30% blastomere loss, verified by differential dye exclusion test, was tolerated in vitrified embryos, >50% blastomeres loss in non-expanded blastocysts implied the minimal essential cell survival rate for blastocoelic cavity re-expansion in vitrified cloned camel blastocysts, irrespective of vitrification method. A protocol-based exposure of embryos to cryoprotectants indicated that cryoprotectant toxicity, per se, may not be involved in lower cryosurvival of embryos in CVP vs. Cryotec and Kitazato. The initial pregnancy rates were numerically higher in Cryotec and Kitazato frozen transfers compared to fresh transfer (56.3, 60 and 33.3%, respectively), and importantly, a higher percentage of established pregnancies in vitrified groups passed the critical 3 months period of early embryonic loss compared to sibling fresh clone pregnancies (50, 40, and 10%, respectively). Results confirmed the suitability of Cryotec and Kitazato kits for vitrification of cloned camel embryos and that vitrification may improve pregnancy outcome by weeding out poor competent embryos.


Assuntos
Blastocisto/fisiologia , Clonagem de Organismos/métodos , Criopreservação/métodos , Transferência Embrionária/métodos , Embrião de Mamíferos/citologia , Animais , Blastômeros , Camelus , Crioprotetores/farmacologia , Feminino , Congelamento , Humanos , Gravidez , Resultado da Gravidez , Taxa de Gravidez , Vitrificação
3.
Int J Biometeorol ; 62(7): 1187-1197, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29546488

RESUMO

Vegetation indices are useful tools to remotely estimate several important parameters related to ecosystem functioning. However, improving and validating estimations for a wide range of vegetation types are necessary. In this study, we provide a methodology for the estimation of the leaf area index (LAI) in a tropical dry forest (TDF) using the light diffusion through the canopy as a function of the successional stage. For this purpose, we estimated the K coefficient, a parameter that relates the normalized difference vegetation index (NDVI) to LAI, based on photosynthetically active radiation (PAR) and solar radiation. The study was conducted in the Mata Seca State Park, in southeastern Brazil, from 2012 to 2013. We defined four successional stages (very early, early, intermediate, and late) and established one optical phenology tower at one plot of 20 × 20 m per stage. Towers measured the incoming and reflected solar radiation and PAR for NDVI calculation. For each plot, we established 24 points for LAI sampling through hemispherical photographs. Because leaf cover is highly seasonal in TDFs, we determined ΔK (leaf growth phase) and Kmax (leaf maturity phase). We detected a strong correlation between NDVI and LAI, which is necessary for a reliable determination of the K coefficient. Both NDVI and LAI varied significantly between successional stages, indicating sensitivity to structural changes in forest regeneration. Furthermore, the K values differed between successional stages and correlated significantly with other environmental variables such as air temperature and humidity, fraction of absorbed PAR, and soil moisture. Thus, we established a model based on spectral properties of the vegetation coupled with biophysical characteristics in a TDF that makes possible to estimate LAI from NDVI values. The application of the K coefficient can improve remote estimations of forest primary productivity and gases and energy exchanges between vegetation and atmosphere. This model can be applied to distinguish different successional stages of TDFs, supporting environmental monitoring and conservation policies towards this biome.


Assuntos
Ecossistema , Folhas de Planta , Clima Tropical , Brasil , Monitoramento Ambiental , Florestas , Estações do Ano
4.
Obes Pillars ; 11: 100115, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38983905

RESUMO

Introduction: This case study portrays an unusual case of treatment-induced neuropathy of diabetes (TIND) in a patient with uncontrolled type 2 diabetes (T2D) who achieved rapid improvement in glucose control primarily with dietary intervention. Initial presentation was 50-year-old white male with a long-standing history of obesity and a family history of T2D with a screening glucose level >500mg/dL by glucometer, HbA1c of 14.9%, and initial weight 213 lbs. Methods: The initial intervention included a low-carbohydrate diet, metformin, and a continuous glucose monitor (CGM). Semaglutide was added after seven days. Results: His glycemia was within the target range within three weeks. Four weeks after initiation of therapy, he developed TIND symptoms consisting of burning, tightness, and numbness of bilateral feet along with 10/10 pain. At three months, his HbA1c dropped to 6.9% and his weight to 195 lbs. Treatment of his TIND reduced his pain from 10/10 to 2/10. Conclusion: Whereas TIND is commonly associated with the use of insulin or sulfonylureas, this study adds evidence to the paucity of literature regarding TIND precipitated by dietary intervention.

5.
Am J Ophthalmol Case Rep ; 36: 102106, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39161377

RESUMO

Purpose: To report on a case of the successful treatment of Acute Posterior Multifocal Placoid Pigment Epitheliopathy (APMPPE) in a pediatric patient with a prior diagnosis of cerebral vasculitis. Observations: A 16-year-old male with a prior diagnosis of cerebral vasculitis presented without ocular complaints. Visual acuity was 20/20, and color vision remained normal. Fundus examination revealed yellowish-white placoid lesions and retinal pigmented epithelial changes involving the posterior pole. A work-up including a rapid plasma reagin test, complete cell blood count, comprehensive metabolic panel, and urinalysis was within normal limits. A head computed tomography angiography without contrast and a brain magnetic resonance imaging scan were compatible with acute and past episodes of ischemia. Ancillary testing was compatible with an assessment APMPPE. Immunosuppressive and monoclonal antibody therapy resulted in the improvement and remission without residual neurologic deficits and with a BCVA of 20/20. Conclusionand Importance: This case suggests that a diagnosis of cerebral vasculitis should prompt physicians to consider an ophthalmic evaluation that includes a dilated fundus exam, regardless of the presence or absence of ocular symptoms. Ophthalmic findings may affect the diagnostic processes, particularly concerning infectious and non-infectious etiologies, or potentially neoplastic diseases.

6.
Materials (Basel) ; 17(13)2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38998352

RESUMO

Escalating global surface temperatures are highlighting the urgent need for energy-saving solutions. Phase-change materials (PCMs) have emerged as a promising avenue for enhancing thermal comfort in the construction sector. This study assessed the impact of incorporating PCMs ranging from 1% to 10% by mass into composite Portland cement partially replaced by fly ash (FA) and nanosilica particles (NS). Mechanical and electrochemical techniques were utilized to evaluate composite cements. The results indicate that the presence of PCMs delayed cement hydration, acting as a filler without chemically interacting within the composite. The combination of FA and PCMs reduced compressive strength at early ages, while thermal conductivity decreased after 90 days due to the melting point and the latent heat of PCMs. Samples with FA and NS showed a significant reduction in the CO2 penetration, attributed to their pozzolanic and microfiller effects, as well as reduced water absorption due to the non-absorptive nature of PCMs. Nitrogen physisorption confirmed structural changes in the cement matrix. Additionally, electrical resistivity and thermal behavior assessments revealed that PCM-containing samples could reduce temperatures by an average of 4 °C. This suggested that PCMs could be a viable alternative for materials with thermal insulation capacity, thereby contributing to energy efficiency in the construction sector.

7.
Polymers (Basel) ; 16(9)2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38732749

RESUMO

Wounds are breaks in the continuity of the skin and underlying tissues, resulting from external causes such as cuts, blows, impacts, or surgical interventions. Countless individuals suffer minor to severe injuries, with unfortunate cases even leading to death. In today's scenario, several commercial products are available to facilitate the healing process of wounds, although chronic wounds still present more challenges than acute wounds. Nevertheless, the huge demand for wound-care products within the healthcare sector has given rise to a rapidly growing market, fostering continuous research and development endeavors for innovative wound-healing solutions. Today, there are many commercially available products including those based on natural biopolymers, stem cells, and microRNAs that promote healing from wounds. This article explores the recent breakthroughs in wound-healing products that harness the potential of natural biopolymers, stem cells, and microRNAs. A comprehensive exploration is undertaken, covering not only commercially available products but also those still in the research phase. Additionally, we provide a thorough examination of the opportunities, obstacles, and regulatory considerations influencing the potential commercialization of wound-healing products across the diverse markets of Europe, America, and Asia.

8.
Cureus ; 15(4): e38154, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37252519

RESUMO

We report a case of idiopathic retinal vasculitis, aneurysms, and neuroretinitis (IRVAN) syndrome in a patient whose cystoid macular edema (CME) was successfully treated with aflibercept and pan-retinal photocoagulation (PRP). A 56-year-old male was sent to our uveitis service for further evaluation after a fluorescein angiogram revealed symmetric retinal ischemia for 360 degrees in both eyes. A fundus examination revealed an aneurysm, neuroretinitis, and occlusive vasculitis, all consistent with a diagnosis of IRVAN syndrome. An optical coherence tomography examination revealed CME of the left eye. A chest X-ray revealed minimally prominent interstitial markings. The patient had a positive QuantiFERON-TB Gold test and was treated for tuberculosis with a one-year course of isoniazid and pyrimethamine. A further workup for other infectious and autoimmune etiologies was negative. The initial treatment consisted of bilateral PRP of the areas of peripheral ischemia, treatment for which was provided in a fragmented fashion over the course of seven months. Soon after the diagnosis, he received treatment with two intravitreal injections of aflibercept (2 mg/0.5 mL), one month apart, to the left eye. Subsequently, four months following the presentation, he developed CME in the right eye, which was treated with a single intravitreal injection of aflibercept (2 mg/0.5 mL). At his last follow-up visit, four years after the initial presentation, the patient remained asymptomatic with 20/20 visual acuity in both eyes and no evidence of CME recurrence. Our case suggests that aflibercept may serve as an adjuvant to the standard treatment with PRP, especially in cases that present with associated macular edema.

9.
J Cell Biol ; 222(4)2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-36729023

RESUMO

How cells simultaneously assemble actin structures of distinct sizes, shapes, and filamentous architectures is still not well understood. Here, we used budding yeast as a model to investigate how competition for the barbed ends of actin filaments might influence this process. We found that while vertebrate capping protein (CapZ) and formins can simultaneously associate with barbed ends and catalyze each other's displacement, yeast capping protein (Cap1/2) poorly displaces both yeast and vertebrate formins. Consistent with these biochemical differences, in vivo formin-mediated actin cable assembly was strongly attenuated by the overexpression of CapZ but not Cap1/2. Multiwavelength live cell imaging further revealed that actin patches in cap2∆ cells acquire cable-like features over time, including recruitment of formins and tropomyosin. Together, our results suggest that the activities of S. cerevisiae Cap1/2 have been tuned across evolution to allow robust cable assembly by formins in the presence of high cytosolic levels of Cap1/2, which conversely limit patch growth and shield patches from formins.


Assuntos
Proteínas de Capeamento de Actina , Actinas , Proteínas de Saccharomyces cerevisiae , Proteínas de Capeamento de Actina/metabolismo , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Citosol/metabolismo , Forminas/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteína de Capeamento de Actina CapZ/metabolismo
10.
J Cell Biol ; 222(12)2023 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-37801069

RESUMO

Understanding how numerous actin-binding proteins (ABPs) work in concert to control the assembly, organization, and turnover of the actin cytoskeleton requires quantitative information about the levels of each component. Here, we measured the cellular concentrations of actin and the majority of the conserved ABPs in Saccharomyces cerevisiae, as well as the free (cytosolic) fractions of each ABP. The cellular concentration of actin is estimated to be 13.2 µM, with approximately two-thirds in the F-actin form and one-third in the G-actin form. Cellular concentrations of ABPs range from 12.4 to 0.85 µM (Tpm1> Pfy1> Cof1> Abp1> Srv2> Abp140> Tpm2> Aip1> Cap1/2> Crn1> Sac6> Twf1> Arp2/3> Scp1). The cytosolic fractions of all ABPs are unexpectedly high (0.6-0.9) and remain so throughout the cell cycle. Based on these numbers, we speculate that F-actin binding sites are limited in vivo, which leads to high cytosolic levels of ABPs, and in turn helps drive the rapid assembly and turnover of cellular F-actin structures.


Assuntos
Actinas , Proteínas dos Microfilamentos , Proteínas de Saccharomyces cerevisiae , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Proteínas dos Microfilamentos/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Citosol/metabolismo
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