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1.
EMBO Rep ; 25(2): 902-926, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38177924

RESUMO

Viruses interact with numerous host factors to facilitate viral replication and to dampen antiviral defense mechanisms. We currently have a limited mechanistic understanding of how SARS-CoV-2 binds host factors and the functional role of these interactions. Here, we uncover a novel interaction between the viral NSP3 protein and the fragile X mental retardation proteins (FMRPs: FMR1, FXR1-2). SARS-CoV-2 NSP3 mutant viruses preventing FMRP binding have attenuated replication in vitro and reduced levels of viral antigen in lungs during the early stages of infection. We show that a unique peptide motif in NSP3 binds directly to the two central KH domains of FMRPs and that this interaction is disrupted by the I304N mutation found in a patient with fragile X syndrome. NSP3 binding to FMRPs disrupts their interaction with the stress granule component UBAP2L through direct competition with a peptide motif in UBAP2L to prevent FMRP incorporation into stress granules. Collectively, our results provide novel insight into how SARS-CoV-2 hijacks host cell proteins and provides molecular insight into the possible underlying molecular defects in fragile X syndrome.


Assuntos
COVID-19 , Síndrome do Cromossomo X Frágil , Humanos , Proteína do X Frágil da Deficiência Intelectual/genética , Proteína do X Frágil da Deficiência Intelectual/metabolismo , Síndrome do Cromossomo X Frágil/genética , Síndrome do Cromossomo X Frágil/metabolismo , Peptídeos/metabolismo , Proteínas de Ligação a RNA/genética , SARS-CoV-2
2.
Cereb Cortex ; 34(2)2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-38425213

RESUMO

The size and shape of the cerebral cortex have changed dramatically across evolution. For some species, the cortex remains smooth (lissencephalic) throughout their lifetime, while for other species, including humans and other primates, the cortex increases substantially in size and becomes folded (gyrencephalic). A folded cortex boasts substantially increased surface area, cortical thickness, and neuronal density, and it is therefore associated with higher-order cognitive abilities. The mechanisms that drive gyrification in some species, while others remain lissencephalic despite many shared neurodevelopmental features, have been a topic of investigation for many decades, giving rise to multiple perspectives of how the gyrified cerebral cortex acquires its unique shape. Recently, a structurally unique germinal layer, known as the outer subventricular zone, and the specialized cell type that populates it, called basal radial glial cells, were identified, and these have been shown to be indispensable for cortical expansion and folding. Transcriptional analyses and gene manipulation models have provided an invaluable insight into many of the key cellular and genetic drivers of gyrification. However, the degree to which certain biomechanical, genetic, and cellular processes drive gyrification remains under investigation. This review considers the key aspects of cerebral expansion and folding that have been identified to date and how theories of gyrification have evolved to incorporate this new knowledge.


Assuntos
Córtex Cerebral , Neurônios , Animais , Humanos , Córtex Cerebral/metabolismo , Neurônios/metabolismo , Ventrículos Laterais/metabolismo , Primatas
3.
J Neurochem ; 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38742992

RESUMO

Intrauterine growth restriction (IUGR) is a pregnancy complication impairing fetal growth and development. The compromised development is often attributed to disruptions of oxygen and nutrient supply from the placenta, resulting in a number of unfavourable physiological outcomes with impaired brain and organ growth. IUGR is associated with compromised development of both grey and white matter, predisposing the infant to adverse neurodevelopmental outcomes, including long-lasting cognitive and motor difficulties. Cerebral thyroid hormone (TH) signalling, which plays a crucial role in regulating white and grey matter development, is dysregulated in IUGR, potentially contributing to the neurodevelopmental delays associated with this condition. Notably, one of the major TH transporters, monocarboxylate transporter-8 (MCT8), is deficient in the fetal IUGR brain. Currently, no effective treatment to prevent or reverse IUGR exists. Management strategies involve close antenatal monitoring, management of maternal risk factors if present and early delivery if IUGR is found to be severe or worsening in utero. The overall goal is to determine the most appropriate time for delivery, balancing the risks of preterm birth with further fetal compromise due to IUGR. Drug candidates have shown either adverse effects or little to no benefits in this vulnerable population, urging further preclinical and clinical investigation to establish effective therapies. In this review, we discuss the major neuropathology of IUGR driven by uteroplacental insufficiency and the concomitant long-term neurobehavioural impairments in individuals born IUGR. Importantly, we review the existing clinical and preclinical literature on cerebral TH signalling deficits, particularly the impaired expression of MCT8 and their correlation with IUGR. Lastly, we discuss the current evidence on MCT8-independent TH analogues which mimic the brain actions of THs by being metabolised in a similar manner as promising, albeit underappreciated approaches to promote grey and white matter development and improve the neurobehavioural outcomes following IUGR.

4.
J Neuroinflammation ; 21(1): 142, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38807204

RESUMO

BACKGROUND: Intrauterine inflammation is considered a major cause of brain injury in preterm infants, leading to long-term neurodevelopmental deficits. A potential contributor to this brain injury is dysregulation of neurovascular coupling. We have shown that intrauterine inflammation induced by intra-amniotic lipopolysaccharide (LPS) in preterm lambs, and postnatal dopamine administration, disrupts neurovascular coupling and the functional cerebral haemodynamic responses, potentially leading to impaired brain development. In this study, we aimed to characterise the structural changes of the neurovascular unit following intrauterine LPS exposure and postnatal dopamine administration in the brain of preterm lambs using cellular and molecular analyses. METHODS: At 119-120 days of gestation (term = 147 days), LPS was administered into the amniotic sac in pregnant ewes. At 126-7 days of gestation, the LPS-exposed lambs were delivered, ventilated and given either a continuous intravenous infusion of dopamine at 10 µg/kg/min or isovolumetric vehicle solution for 90 min (LPS, n = 6; LPSDA, n = 6). Control preterm lambs not exposed to LPS were also administered vehicle or dopamine (CTL, n = 9; CTLDA, n = 7). Post-mortem brain tissue was collected 3-4 h after birth for immunohistochemistry and RT-qPCR analysis of components of the neurovascular unit. RESULTS: LPS exposure increased vascular leakage in the presence of increased vascular density and remodelling with increased astrocyte "end feet" vessel coverage, together with downregulated mRNA levels of the tight junction proteins Claudin-1 and Occludin. Dopamine administration decreased vessel density and size, decreased endothelial glucose transporter, reduced neuronal dendritic coverage, increased cell proliferation within vessel walls, and increased pericyte vascular coverage particularly within the cortical and deep grey matter. Dopamine also downregulated VEGFA and Occludin tight junction mRNA, and upregulated dopamine receptor DRD1 and oxidative protein (NOX1, SOD3) mRNA levels. Dopamine administration following LPS exposure did not exacerbate any effects induced by LPS. CONCLUSION: LPS exposure and dopamine administration independently alters the neurovascular unit in the preterm brain. Alterations to the neurovascular unit may predispose the developing brain to further injury.


Assuntos
Animais Recém-Nascidos , Dopamina , Lipopolissacarídeos , Animais , Dopamina/metabolismo , Ovinos , Feminino , Lipopolissacarídeos/toxicidade , Gravidez , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Inflamação/induzido quimicamente , Inflamação/metabolismo , Inflamação/patologia , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/patologia , Nascimento Prematuro/induzido quimicamente , Nascimento Prematuro/patologia
5.
Transgenic Res ; 33(4): 255-266, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38981975

RESUMO

The p75NTR neurotrophin receptor has positive and negative roles regulating cell survival in the nervous system. Unambiguous interpretation of p75NTR function in vivo has been complicated, however, by residual expression of alternate forms of p75NTR protein in initial p75NTR knock-out mouse models. As rats are the preferred rodent for studying brain and behaviour, and to simplify interpretation of the knock-out phenotype, we report here the generation of a mutant rat devoid of the p75NTR protein. TALEN-mediated recombination in embryonic stem cells (ESCs) was used to flank exon 2 of p75NTR with Lox P sites and produce transgenic rats carrying either un-recombined floxed p75NTREx2-fl, or recombined, exon-2 deleted p75NTREx2-Δ alleles. Crossing p75NTREx2-fl rats with a Cre-deleter strain efficiently removed exon 2 in vivo. Excision of exon 2 causes a frameshift after p75NTR Gly23 and eliminated p75NTR protein expression. Rats lacking p75NTR were healthy, fertile, and histological analysis did not reveal significant changes in cellular density or overall structure in their brains. p75NTR function is therefore largely dispensable for normal development, growth and basal homeostasis in the rat. However, the availability of constitutive and conditional p75NTREx2-Δ rats provides new opportunities to investigate specific roles of p75NTR upon injury and during tissue repair.


Assuntos
Ratos Transgênicos , Animais , Ratos , Receptores de Fator de Crescimento Neural/genética , Receptores de Fator de Crescimento Neural/metabolismo , Fertilidade/genética , Feminino , Encéfalo/metabolismo , Encéfalo/crescimento & desenvolvimento , Masculino , Éxons/genética , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Células-Tronco Embrionárias/metabolismo , Receptores de Fatores de Crescimento
6.
Pediatr Blood Cancer ; : e31253, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-39126369

RESUMO

BACKGROUND: Many studies highlight poor health-related quality of life (HRQoL) in children treated for brain tumours and their parents. However, little is known about the extent to which their informational, healthcare and communication needs regarding HRQoL are met during medical outpatient consultations. AIM: To explore the experiences of families regarding communication with physicians about HRQoL issues during consultations after treatment for childhood brain tumours. METHODS: Interviews were conducted with 18 families of children and adolescents aged 8-17 years after completion of brain tumour treatment. Participants had completed treatment within the last 5 years and were receiving regular outpatient follow-up care. Thematic analysis was undertaken using the Framework Method. RESULTS: Five main themes were identified: (i) unmet emotional and mental health needs; (ii) double protection; (iii) unmet information needs; (iv) communication barriers within consultations; and (v) finding a new normal. CONCLUSION: There was a need to improve communication between clinicians and these families, improve information provision, and overcome barriers to conversing with children within these outpatient consultations. Children and their parents should be supported to voice their current needs and concerns regarding their HRQoL. These findings will inform further development of the UK version of the 'KLIK' patient- and parent-reported outcome (PROM) portal.

7.
Neurourol Urodyn ; 43(2): 437-448, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38108212

RESUMO

INTRODUCTION: Overactive bladder (OAB) can adversely affect health-related quality-of-life (HRQoL) and adherence to treatments; however, the extent of their association is unknown. This study sought to characterize Sleep Disturbance, Depression, Fatigue, and patient-reported medication adherence among adults with OAB in the United States. MATERIALS AND METHODS: In this descriptive, observational study, patients completed patient-reported outcome (PRO) measures of urinary symptoms, anxiety, depression, fatigue, sleep quality, and medication adherence. PRO scores were compared across age, sex, body mass index, and sleep and antidepressant medication-taking subgroups. Exploratory analyses compared PRO scores between groups and estimated the effect size of differences. RESULTS: Of 1013 patients contacted, 159 completed the assessments (female: 67.3%; ≥65 years of age: 53.5%; most severe OAB symptom: nocturia). Scale scores for Sleep Disturbance, Fatigue, and Depression were consistent with US population norms. No correlations of moderate or greater magnitude were observed between the severity of lower urinary tract symptoms and Sleep Disturbance, Fatigue, or Depression. When comparing individuals receiving antidepressants with those who were not, almost all outcomes including urinary symptoms, anxiety, and depression were significantly worse. Patients taking antidepressants also had poorer adherence to their OAB medications. CONCLUSION: In this cohort of individuals with OAB, Sleep Disturbance, Fatigue, and Depression scores were in line with general population reference values; however, among the subgroups analyzed, patients on antidepressants had worse HRQoL and more substantial impacts on medication adherence, highlighting the importance of the assessment and management of depression in this population.


Assuntos
Bexiga Urinária Hiperativa , Adulto , Humanos , Feminino , Estados Unidos , Pessoa de Meia-Idade , Bexiga Urinária Hiperativa/diagnóstico , Depressão/epidemiologia , Qualidade do Sono , Qualidade de Vida , Medidas de Resultados Relatados pelo Paciente , Antidepressivos/uso terapêutico , Fadiga
8.
Food Microbiol ; 120: 104478, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38431324

RESUMO

An optimized digital RT-PCR (RT-dPCR) assay for the detection of human norovirus GI and GII RNA was compared with ISO 15216-conform quantitative real-time RT-PCR (RT-qPCR) assays in an interlaboratory study (ILS) among eight laboratories. A duplex GI/GII RT-dPCR assay, based on the ISO 15216-oligonucleotides, was used on a Bio-Rad QX200 platform by six laboratories. Adapted assays for Qiagen Qiacuity or ThermoFisher QuantStudio 3D were used by one laboratory each. The ILS comprised quantification of norovirus RNA in the absence of matrix and in oyster tissue samples. On average, results of the RT-dPCR assays were very similar to those obtained by RT-qPCR assays. The coefficient of variation (CV%) of norovirus GI results was, however, much lower for RT-dPCR than for RT-qPCR in intra-laboratory replicates (eight runs) and between the eight laboratories. The CV% of norovirus GII results was in the same range for both detection formats. Had in-house prepared dsDNA standards been used, the CV% of norovirus GII could have been in favor of the RT-dPCR assay. The ratio between RT-dPCR and RT-qPCR results varied per laboratory, despite using the distributed RT-qPCR dsDNA standards. The study indicates that the RT-dPCR assay is likely to increase uniformity of quantitative results between laboratories.


Assuntos
Norovirus , Ostreidae , Animais , Humanos , Norovirus/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Alimentos Marinhos/análise , RNA Viral/genética
9.
Undersea Hyperb Med ; 51(2): 137-144, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38985150

RESUMO

Objective: To analyze Hyperbaric Oxygen Therapy Registry (HBOTR) data to estimate the Medicare costs of hyperbaric oxygen therapy (HBO2) based on standard treatment protocols and the annual mean number of treatments per patient reported by the registry. Methods: We performed a secondary analysis of deidentified data for all payers from 53 centers registered in the HBOTR from 2013 to 2022. We estimated the mean annual per-patient costs of HBO2 based on Medicare (outpatient facility + physician) reimbursement fees adjusted to 2022 inflation using the Medicare Economic Index. Costs were calculated for the annual average number of treatments patients received each year and for a standard 40-treatment series. We estimated the 2022 costs of standard treatment protocols for HBO2 indications treated in the outpatient setting. Results: Generally, all costs decreased from 2013 to 2022. The facility cost per patient per 40 HBO2 treatments decreased by 10.7% from $21,568.58 in 2013 to $19,488.00 in 2022. The physician cost per patient per 40 treatments substantially decreased by -37.8%, from $5,993.16 to $4,346.40. The total cost per patient per 40 treatments decreased by 15.6% from $27,561.74 to $23,834.40. In 2022, a single HBO2 session cost $595.86. For different indications, estimated costs ranged from $2,383.4-$8,342.04 for crush injuries to $17,875.80-$35,751.60 for diabetic foot ulcers and delayed radiation injuries. Conclusions: This real-world analysis of registry data demonstrates that the actual cost of HBO2 is not nearly as costly as the literature has insinuated, and the per-patient cost to Medicare is decreasing, largely due to decreased physician costs.


Assuntos
Oxigenoterapia Hiperbárica , Medicare , Sistema de Registros , Oxigenoterapia Hiperbárica/economia , Oxigenoterapia Hiperbárica/estatística & dados numéricos , Humanos , Medicare/economia , Estados Unidos , Custos de Cuidados de Saúde/estatística & dados numéricos
11.
J Endocrinol ; 262(1)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38692289

RESUMO

CD44, a cell surface adhesion receptor and stem cell biomarker, is recently implicated in chronic metabolic diseases. Ablation of CD44 ameliorates adipose tissue inflammation and insulin resistance in obesity. Here, we investigated cell type-specific CD44 expression in human and mouse adipose tissue and further studied how CD44 in preadipocytes regulates adipocyte function. Using Crispr Cas9-mdediated gene deletion and lentivirus-mediated gene re-expression, we discovered that deletion of CD44 promotes adipocyte differentiation and adipogenesis, whereas re-expression of CD44 abolishes this effect and decreases insulin responsiveness and adiponectin secretion in 3T3-L1 cells. Mechanistically, CD44 does so via suppressing Pparg expression. Using quantitative proteomics analysis, we further discovered that cell cycle-regulated pathways were mostly decreased by deletion of CD44. Indeed, re-expression of CD44 moderately restored expression of proteins involved in all phases of the cell cycle. These data were further supported by increased preadipocyte proliferation rates in CD44-deficient cells and re-expression of CD44 diminished this effect. Our data suggest that CD44 plays a crucial role in regulating adipogenesis and adipocyte function possibly through regulating PPARγ and cell cycle-related pathways. This study provides evidence for the first time that CD44 expressed in preadipocytes plays key roles in regulating adipocyte function outside immune cells where CD44 is primarily expressed. Therefore, targeting CD44 in (pre)adipocytes may provide therapeutic potential to treat obesity-associated metabolic complications.


Assuntos
Células 3T3-L1 , Adipócitos , Adipogenia , Ciclo Celular , Receptores de Hialuronatos , PPAR gama , Adipogenia/genética , Adipogenia/fisiologia , Receptores de Hialuronatos/metabolismo , Receptores de Hialuronatos/genética , Animais , PPAR gama/metabolismo , PPAR gama/genética , Camundongos , Ciclo Celular/genética , Ciclo Celular/fisiologia , Humanos , Adipócitos/metabolismo , Deleção de Genes , Diferenciação Celular/genética , Masculino , Tecido Adiposo/metabolismo , Tecido Adiposo/citologia , Transdução de Sinais/fisiologia
12.
Urology ; 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39154839

RESUMO

OBJECTIVE: To call to attention the often-overlooked aspect of pediatric transgender care: the importance of fertility preservation prior to instituting gender-affirming therapy. The transgender population has long been marginalized by society. Societal stigmata, fear to seek care, and dearth of provider knowledge regarding transgender health issues has caused disparities to widen. Gender affirming procedures and hormone therapy affect the long-term reproductive potential of transgender individuals. While cost concerns and insurance coverage regarding oncofertility is a prominent area of discussion, the transgender community is often excluded. METHODS: Sixteen genetically XY females, followed by their multidisciplinary transgender care teams, were interested in starting hormone therapy due to impending onset and/or progression of puberty. Their physicians were aware of fertility struggles after undergoing hormone therapy and therefore referred to urology. Sperm cryopreservation via open gonadal biopsy, testicular tissue cryopreservation (TTC), and semen sample (when age/maturity-appropriate) were discussed. Though requiring surgery, biopsy/TTC relieves patients of the psychological impact of semen sample production. RESULTS: Under IRB approval, 15 patients (median age 12 years, range 10-16 years) underwent TTC (Figure 1). One patient (aged years) opted for semen sample. All patients had success with spermatogonial stem cells cryopreserved for future patient use. CONCLUSIONS: With more individuals beginning medical and surgical therapy at a younger age, fertility preservation discussions are essential but often overlooked, depriving these individuals the joy of becoming a biological parent. TTC can be safely done in pediatric populations, though research is necessary to expand beyond current experimental stage of tissue-development.

13.
J Mater Chem B ; 12(33): 8087-8098, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39007256

RESUMO

Prussian blue is known for its high affinity for thallium and other univalent metal cations and has been used as a treatment for radiocaesium and thallium/radiothallium poisoning. While Prussian blue nanoparticles (PBNPs) show potential for binding radioactive thallium for further use in nuclear medicine applications, the inclusion mechanism remains elusive. Understanding the interaction between PBNPs and 201Tl is essential for identifying the physicochemical and radiochemical properties required for optimal in vivo performance. In this work, we evaluated the binding mechanism between Tl and PBNPs with different coatings and core shapes. Combining PBNPs with [201Tl] thallium(I) chloride provided high radiolabelling yields and radiochemical stabilities under physiological conditions. Comprehensive characterisation by different X-ray techniques confirmed that Tl ions are located in the interstitial sites within the crystal structure, maintaining the integrity of the iron (Fe) 4p electronic distribution and inducing local modifications in the nearby C-N ligands. Additionally, this inclusion does not impact the core or the shell of the nanoparticles but does alter their ionic composition. The PB ionic network undergoes significant changes, with a substantial drop in K+ content, confirming that Tl+ ions replace K+ and occupy additional spaces within the crystal structure. These results open new opportunities in nuclear medicine applications with 201Tl-PBNPs where the size, shape and composition of the particles can be specifically tuned depending on the desired biological properties without affecting the radiochemical performance as a vehicle for 201Tl.


Assuntos
Ferrocianetos , Nanopartículas , Tálio , Ferrocianetos/química , Nanopartículas/química , Tálio/química , Radioisótopos de Tálio/química , Medicina Nuclear , Tamanho da Partícula
14.
Cardiovasc Pathol ; 72: 107661, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38801983

RESUMO

The epidemic caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has had a significant global impact, especially on immunosuppressed populations such as heart transplant recipients. While SARS-CoV-2 initially infects the respiratory system, cardiovascular complications induced by coronavirus disease 2019 (COVID-19) include cardiac arrest, myocardial infarction, heart failure, myocarditis, arrhythmia, acute myocyte injury, thrombotic events, and cardiogenic shock. Here, we present a case of a 45-year-old African American male who tested positive for COVID-19 infection six months after receiving a heart transplant. The patient was asymptomatic initially, but two weeks later he developed dyspnea, early satiety, and abdominal bloating. The patient was admitted to the hospital for acute renal failure and subsequently diagnosed with moderate acute T cell-mediated allograft rejection (Grade 2R) by endomyocardial biopsy. Three months after testing positive for COVID-19, the patient suffered a sudden cardiac death. At autopsy, the epicardium was diffusely edematous and showed vascular congestion. The coronary arteries showed a striking concentric narrowing of lumens and diffusely thickened arterial walls of all major extramural arteries deemed consistent with a rapidly progressive form of cardiac allograft vasculopathy (CAV). SARS-CoV-2 nucleocapsid protein was localized by immunohistochemistry (IHC) in endothelial cells of venules and capillaries within the epicardium. Our localization of SARS-CoV-2 in coronary vessel endothelial cells by IHC suggests that endothelial cell infection, endotheliitis, and immune-related inflammation may be a primary mechanism of vascular injury. The present case represents an early onset rapidly progressive form of CAV. This case may be the first case of post-transplant arteriopathy occurring in such a short time that includes corresponding autopsy, surgical pathology, and IHC data.


Assuntos
COVID-19 , Transplante de Coração , Humanos , COVID-19/complicações , Transplante de Coração/efeitos adversos , Masculino , Pessoa de Meia-Idade , Evolução Fatal , Rejeição de Enxerto/patologia , Rejeição de Enxerto/imunologia , SARS-CoV-2/patogenicidade , Progressão da Doença , Morte Súbita Cardíaca/etiologia , Morte Súbita Cardíaca/patologia , Doença da Artéria Coronariana/patologia , Doença da Artéria Coronariana/etiologia
15.
J Phys Chem C Nanomater Interfaces ; 128(31): 13108-13120, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39140097

RESUMO

Improved knowledge of the influence of temperature upon layered perovskites is essential to enable perovskite-based devices to operate over a broad temperature range and to elucidate the impact of structural changes upon the optoelectronic properties. We examined the Ruddlesden-Popper layered perovskite 2-thiophenemethylammonium lead iodide (ThMA2PbI4) and observed a structural phase transition between a high- and a low-temperature phase at 220 K using temperature-dependent X-ray diffraction, UV-visible absorption, and photoluminescence (PL) spectroscopy. The structural phase transition altered the tilt pattern of the inorganic octahedra layer, modifying the absorption and PL spectra. Further, we found a narrow and intense additional PL peak in the low-temperature phase, which we assigned to radiative emission from a defect-bound exciton state. In both phases we determined the thermal expansion coefficient and found values similar to those of cubic 3D perovskites, i.e., larger than those of typical substrates such as glass. These results demonstrate that the organic spacer plays a critical role in controlling the temperature-dependent structural and optoelectronic properties of layered perovskites and suggests more widely that strain management strategies may be needed to fully utilize layered perovskites in device applications.

16.
Microbiol Resour Announc ; 13(8): e0021824, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39046228

RESUMO

In Bangladesh, free-range duck farms provide opportunities for the generation of novel influenza A viruses as evidenced by the emergence of an unusual A(H1N7) virus in 2023. Continued surveillance of such environments for the potential emergence of influenza A viruses with novel properties remains a priority.

17.
PLoS Negl Trop Dis ; 18(7): e0012276, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38990838

RESUMO

Rocky Mountain spotted fever (RMSF), a severe and extraordinarily lethal infectious disease, has emerged as a widespread public health crisis among predominantly vulnerable populations in several countries of Latin America, particularly evident in northern Mexico. Historically, RMSF has gained less attention than many other tropical infectious diseases, resulting in insufficient allocations of resources and development of capabilities for its prevention and control in endemic regions. We argue that RMSF fulfills accepted criteria for a neglected tropical disease (NTD). The relative neglect of RMSF in most Latin American countries contributes to disparities in morbidity and mortality witnessed in this region. By recognizing RMSF as an NTD, an increased public policy interest, equitable and more appropriate allocation of resources, scientific interest, and social participation can ameliorate the impact of this potentially treatable disease, particularly in vulnerable populations.


Assuntos
Doenças Negligenciadas , Febre Maculosa das Montanhas Rochosas , Humanos , América Latina/epidemiologia , Doenças Negligenciadas/epidemiologia , Doenças Negligenciadas/prevenção & controle , Febre Maculosa das Montanhas Rochosas/epidemiologia , Medicina Tropical
18.
Bioresour Technol ; 405: 130932, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38838831

RESUMO

The first comparative pre-treatment study of Miscanthus (Mxg) and sugarcane bagasse (SCB) using steam explosion (SE) and pressurised disc refining (PDR) pretreatment to optimise xylose and xylo-oligosaccharide release is described. The current investigation aimed to 1) Develop optimised batch-wise steam explosion parameters for Mxg and SCB, 2) Scale from static batch steam explosion to dynamic continuous pressurised disc refining, 3) Identify, understand, and circumvent scale-up production hurdles. Optimised SE parameters released 82% (Mxg) and 100% (SCB) of the available xylan. Scaling to PDR, Miscanthus yielded 85% xylan, highlighting how robust scouting assessments for boundary process parameters can result in successful technical transfer. In contrast, SCB technical transfer was not straightforward, with significant differences observed between the two processes, 100% (SE) and 58% (PDR). This report underlines the importance of feedstock-specific pretreatment strategies to underpin process development, scale-up, and optimisation of carbohydrate release from biomass.


Assuntos
Celulose , Oligossacarídeos , Poaceae , Saccharum , Vapor , Xilose , Saccharum/química , Celulose/química , Projetos Piloto , Biotecnologia/métodos , Xilanos , Glucuronatos
19.
Neuropharmacology ; 258: 110093, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39067665

RESUMO

Agonists at µ opioid receptors relieve acute pain, however, their long-term use is limited by side effects, which may involve ß-arrestin2. Agonists biased against ß-arrestin2 recruitment may be advantageous. However, the classification of bias may be compromised by assays utilising overexpressed µ receptors which overestimate efficacy for G-protein activation. There is a need for re-evaluation with restricted receptor availability to determine accurate agonist efficacies. We depleted µ receptor availability in PathHunter CHO cells using the irreversible antagonist, ß-funaltrexamine (ß-FNA), and compared efficacies and apparent potencies of twelve agonists, including several previously reported as biased, in ß-arrestin2 recruitment and cAMP assays. With full receptor availability all agonists had partial efficacy for stimulating ß-arrestin2 recruitment relative to DAMGO, while only TRV130 and buprenorphine were partial agonists as inhibitors of cAMP accumulation. Limiting receptor availability by prior exposure to ß-FNA (100 nM) revealed morphine, oxycodone, PZM21, herkinorin, U47700, tianeptine and U47931e are also partial agonists in the cAMP assay. The efficacies of all agonists, except SR-17018, correlated between ß-arrestin2 recruitment and cAMP assays, with depleted receptor availability in the latter. Furthermore, naloxone and cyprodime exhibited non-competitive antagonism of SR-17018 in the ß-arrestin2 recruitment assay. Limited antagonism by naloxone was also non-competitive in the cAMP assay, while cyprodime was competitive. Furthermore, SR-17018 only negligibly diminished ß-arrestin2 recruitment stimulated by DAMGO (1 µM), whereas fentanyl, morphine and TRV130 all exhibited the anticipated competitive inhibition. The data suggest that SR-17018 achieves bias against ß-arrestin2 recruitment through interactions with µ receptors outside the orthosteric agonist site. This article is part of the Special Issue on "Ligand Bias".


Assuntos
Analgésicos Opioides , Cricetulus , AMP Cíclico , Receptores Opioides mu , Animais , Células CHO , Receptores Opioides mu/metabolismo , Receptores Opioides mu/agonistas , Analgésicos Opioides/farmacologia , AMP Cíclico/metabolismo , Antagonistas de Entorpecentes/farmacologia , Naltrexona/farmacologia , Naltrexona/análogos & derivados , Cricetinae , Humanos , Ala(2)-MePhe(4)-Gly(5)-Encefalina/farmacologia , beta-Arrestinas/metabolismo , Relação Dose-Resposta a Droga , beta-Arrestina 2/metabolismo , Compostos de Espiro , Tiofenos
20.
Nat Commun ; 15(1): 5324, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38909028

RESUMO

One Health is a recognition of the shared environment inhabited by humans, animals and plants, and the impact of their interactions on the health of all organisms. The COVID-19 pandemic highlighted the need for a framework of pathogen surveillance in a tractable One Health paradigm to allow timely detection and response to threats to human and animal health. We present case studies centered around the recent global approach to tackle antimicrobial resistance and the current interest in wastewater testing, with the concept of "one sample many analyses" to be further explored as the most appropriate means of initiating this endeavor.


Assuntos
COVID-19 , Saúde Única , Águas Residuárias , Águas Residuárias/virologia , Humanos , COVID-19/epidemiologia , COVID-19/virologia , COVID-19/transmissão , Animais , SARS-CoV-2/isolamento & purificação , Saúde Global , Pandemias/prevenção & controle
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