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1.
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.

2.
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.

3.
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.

4.
Water Res ; 263: 122152, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39096810

RESUMO

Wastewater-based epidemiology (WBE) gained widespread use as a tool for supporting clinical disease surveillance during the COVID-19 pandemic. There is now significant interest in the continued development of WBE for other pathogens of clinical significance. In this study, approximately 3,200 samples of wastewater from across England, previously collected for quantification of SARS-CoV-2, were re-analysed for the quantification of norovirus genogroup I (GI) and II (GII). Overall, GI and GII were detected in 93% and 98% of samples respectively, and at least one of the genogroups was detected in 99% of samples. GI was found at significantly lower concentrations than GII, but the proportion of each genogroup varied over time, with GI becoming more prevalent than GII in some areas towards the end of the study period (May 2021 - March 2022). Using relative strength indices (RSI), it was possible to study the trends of each genogroup, and total norovirus over time. Increases in norovirus levels appeared to coincide with the removal of COVID-19 related lockdown restrictions within England. Local Moran's I analyses indicated several localised outbreaks of both GI and GII across England, notably the possible GI outbreak in the north of England in early 2022. Comparisons of national average norovirus concentrations in wastewater against concomitant norovirus reported case numbers showed a significant linear relationship. This highlights the potential for wastewater-based monitoring of norovirus as a valuable approach to support surveillance of norovirus in communities.

5.
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
6.
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
7.
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
8.
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
10.
BMJ Open ; 14(7): e083560, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39038857

RESUMO

INTRODUCTION: Acute undifferentiated febrile illnesses (AUFIs) impose a large burden in the tropics. Understanding of AUFI's epidemiology is limited. Insufficient diagnostic capacity hinders the detection of outbreaks. The lack of interconnection in healthcare systems hinders timely response. We describe a protocol to study the epidemiology and aetiologies of AUFI and pathogen discovery in strategic areas of Latin America (LA). METHODS AND ANALYSIS: Global Infectious Diseases Network investigators comprising institutions in Colombia, Dominican Republic, México, Perú and the USA, developed a common cohort study protocol. The primary objective is to determine the aetiologies of AUFI at healthcare facilities in high-risk areas. Data collection and laboratory testing for viral, bacterial and parasitic agents are performed in rural and urban healthcare facilities and partner laboratories. Centralised laboratory and data management cores deploy diagnostic tests and data management tools. Subjects >6 years with fever for <8 days without localised infection are included in the cohort. They are evaluated during the acute and convalescent phases of illness. Study personnel collect clinical and epidemiological information. Blood, urine, nasal or pharyngeal swabs and saliva are collected in the acute phase and blood in convalescent phase. Specimens are banked at -80°C. Malaria, dengue and COVID-19 are tested onsite in the acute phase. The acute-phase serum is PCR tested for dengue, chikungunya, Venezuelan equine encephalitis, Mayaro, Oropouche, Zika, and yellow fever viruses. Paired convalescent and acute serum antibody titters are tested for arbovirus, Leptospira spp, and Rickettsia spp. Serum is used for viral cultures and next-generation sequencing for pathogen discovery. Analysis includes variable distributions, risk factors and regression models. Laboratory results are shared with health authorities and network members. ETHICS AND DISSEMINATION: The protocol was approved by local ethics committees and health authorities. The results will be published in peer-reviewed journals. All study results are shared with local and regional health authorities.


Assuntos
Febre , Humanos , América Latina/epidemiologia , Febre/epidemiologia , Estudos de Coortes , Projetos de Pesquisa , Doença Aguda , COVID-19/epidemiologia , COVID-19/diagnóstico
11.
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.

12.
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
13.
Res Sq ; 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39070617

RESUMO

N-terminal-acetyltransferases including NAA10 catalyze N-terminal acetylation (Nt-acetylation), an evolutionarily conserved co-translational modification. Little is known about the role of Nt-acetylation in cardiac homeostasis. To gain insights, we studied a novel NAA10 variant (p.R4S) segregating with QT-prolongation, cardiomyopathy and developmental delay in a large kindred. Here we show that the NAA10-R4S mutation reduced enzymatic activity, decreased expression levels of NAA10/NAA15 proteins, and destabilized the enzymatic complex NatA. In NAA10R4S/Y-iPSC-CMs, dysregulation of the late sodium and slow rectifying potassium currents caused severe repolarization abnormalities, consistent with clinical QT prolongation. Engineered heart tissues generated from NAA10R4S/Y-iPSC-CMs had significantly decreased contractile force and sarcomeric disorganization, consistent with the pedigree's cardiomyopathic phenotype. We identified small molecule and genetic therapies that normalized the phenotype of NAA10R4S/Y-iPSC-CMs. Our study defines novel roles of Nt-acetylation in cardiac regulation and delineates mechanisms underlying QT prolongation, arrhythmia, and cardiomyopathy caused by NAA10 dysfunction.

14.
Nat Commun ; 15(1): 5929, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39009604

RESUMO

Human iPSC-derived cardiomyocytes (hiPSC-CMs) have proven invaluable for cardiac disease modeling and regeneration. Challenges with quality, inter-batch consistency, cryopreservation and scale remain, reducing experimental reproducibility and clinical translation. Here, we report a robust stirred suspension cardiac differentiation protocol, and we perform extensive morphological and functional characterization of the resulting bioreactor-differentiated iPSC-CMs (bCMs). Across multiple different iPSC lines, the protocol produces 1.2E6/mL bCMs with ~94% purity. bCMs have high viability after cryo-recovery (>90%) and predominantly ventricular identity. Compared to standard monolayer-differentiated CMs, bCMs are more reproducible across batches and have more mature functional properties. The protocol also works with magnetically stirred spinner flasks, which are more economical and scalable than bioreactors. Minor protocol modifications generate cardiac organoids fully in suspension culture. These reproducible, scalable, and resource-efficient approaches to generate iPSC-CMs and organoids will expand their applications, and our benchmark data will enable comparison to cells produced by other cardiac differentiation protocols.


Assuntos
Reatores Biológicos , Técnicas de Cultura de Células , Diferenciação Celular , Células-Tronco Pluripotentes Induzidas , Miócitos Cardíacos , Organoides , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Miócitos Cardíacos/citologia , Miócitos Cardíacos/fisiologia , Organoides/citologia , Técnicas de Cultura de Células/métodos , Reprodutibilidade dos Testes , Células Cultivadas , Criopreservação/métodos
15.
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
16.
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
18.
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
19.
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.

20.
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
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