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1.
Heliyon ; 10(15): e35293, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39170267

RESUMO

Background: Parkinson's disease (PD) is associated with both sleep disturbances and apathy, and within PD, apathy has been associated with REM behavior disorder and excessive daytime sleepiness. Whether other forms of sleep disturbance are similarly associated with apathy in PD remains unclear. This study explored associations between a broad array of sleep disturbances and apathy in 50 individuals with idiopathic PD (PD) and 48 matched controls (MC). Methods: Participants were adults aged 53-80 (Mdn = 67), 23 % female, and 96 % white. Sleep disturbances were measured with various questionnaires (ISI, PSQI, PROMIS-SD, ESS, PROMIS-SRI, RBDSQ). Mood was measured with the STAI and BDI-II. Apathy was evaluated using the Apathy Scale (AS). Spearman correlations and regression analyses were performed between measures of sleep disturbance and AS in the total sample and each group. Group correlations were compared using 2-sample Fisher's z test. Results: The AS total score significantly correlated with PROMIS-SRI in the total sample and multiple measures of sleep disturbance in the PD group. The apathy subscales were each significantly correlated with sleep disturbance measures in the total sample, MC, and PD groups. The correlations between several sleep and apathy values were significantly stronger in the PD group than MC. When accounting for anxiety and depression most differences were no longer significant, only the PROMIS-SRI was significantly predictive of the behavioral apathy sub score. Discussion: Evidence supports an association between sleep disturbances and apathy in individuals with PD. Specifically, insomnia severity, poor sleep quality, and daytime sleepiness were uniquely associated with apathy in this group. We did not find these associations in the matched control group. Anxiety and depression are likely involved in the association between sleep and apathy in PD. Experimental studies that manipulate or improve sleep may further elucidate the mechanisms underlying the association between sleep disturbance and apathy in PD.

2.
J Arthroplasty ; 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39178974

RESUMO

BACKGROUND: This study aimed to evaluate the safety of total knee arthroplasty (TKA) in Jehovah's Witness patients compared to non-Jehovah's Witness patients using standard perioperative TKA protocols and assess the role of tranexamic acid (TXA) in managing blood loss in this population. METHODS: Patients undergoing TKA between 2011 and 2021 at 2 tertiary academic centers were retrospectively reviewed. Patient demographics, preoperative and postoperative hematologic laboratory values, intraoperative TXA use, 90-day postoperative complications, and subsequent revisions were collected. These variables were then compared between propensity score-matched cohorts at a 2:1 ratio of those who did not identify as Jehovah's Witness to those who did. Regression analysis was used to determine the effect of intraoperative TXA on hemoglobin (hgb) shift. RESULTS: After applying exclusion criteria and matching, the TKA outcomes of 316 non-Jehovah's Witness patients and 152 Jehovah's Witness patients were analyzed. Univariate analysis suggested that non-Jehovah's Witness patients and Jehovah's Witness patients had similar preoperative and postoperative hgb, hgb shift, and hematocrit. Only 1 (0.8%) Jehovah's Witness patient reached an hgb < 8.0 mg/dL postoperatively. Multivariate logistic regression suggested that Jehovah's Witness patients did not have increased odds of reaching an hgb < 8.0 mg/dL (odds ratio = 0.99 [0.96, 1.02]; P = 0.42). Multivariate linear regression suggested that intraoperative TXA was positively correlated with hgb shift and thus a smaller decrease in hgb from pre-TKA to post-TKA (ß = 0.38 [0.06, 0.69]; P = 0.02). Additionally, Jehovah's Witness patients had excellent revision-free (95% [91, 99]) and infection-free (98% [95, 100]) survival at 8 years. CONCLUSIONS: Standard perioperative TKA protocols are safe for Jehovah's Witness patients who do not have the need for transfusion, especially with appropriate preoperative hgb levels and the use of intraoperative TXA. Furthermore, these patients have excellent survivorship at 5 and 8 years of follow-up. LEVEL OF EVIDENCE: Level III.

3.
Front Surg ; 11: 1442501, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39149132

RESUMO

Purpose: Despite a growing number of women entering medical school, a small proportion of women pursue surgical specialties, including pediatric surgery. This multi-center study assesses gender-based differences in measures of scholarly productivity and distribution of faculty positions. Methods: This is a retrospective web-based study of all pediatric surgeons at twelve large institutions across the United States. Data published by the American Association of Medical Colleges was compiled and analyzed to understand the gender distributions of medical students, general surgery residents, and pediatric surgery fellows. P-values were calculated using two-sided Student's independent t-tests and chi-squared tests. Results: There have been a growing number of women applying into pediatric surgery, but the proportion of women matriculating into these fellowships is not concordant. Women are still underrepresented (28%) amongst the pediatric surgeon workforce. A total of 111 pediatric surgeons were identified for this study, which included 31 women (28%) and 80 males (72%). There was a significant difference in the distribution across academic ranks between genders (p < 0.001). Women had significantly fewer publications per year after residency, fewer total publications, and a lower h-index in comparison to men (p < .001, p = .005, p = .002, respectively). Conclusions: Women are not only underrepresented in pediatric surgery, but there are also significant differences in the distribution of faculty positions and scholarly productivity when comparing men and women. There is a pressing need to improve gender diversity and identify barriers that may prevent women from advancing to leadership positions and achieving professional success.

4.
mSphere ; : e0049624, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39191392

RESUMO

Methanotrophic bacteria play a vital role in the biogeochemical carbon cycle due to their unique ability to use CH4 as a carbon and energy source. Evidence suggests that some methanotrophs, including Methylococcus capsulatus, can also use CO2 as a carbon source, making these bacteria promising candidates for developing biotechnologies targeting greenhouse gas capture and mitigation. However, a deeper understanding of the dual CH4 and CO2 metabolism is needed to guide methanotroph strain improvements and realize their industrial utility. In this study, we show that M. capsulatus expresses five carbonic anhydrase (CA) isoforms, one α-CA, one γ-CA, and three ß-CAs, that play a role in its inorganic carbon metabolism and CO2-dependent growth. The CA isoforms are differentially expressed, and transcription of all isoform genes is induced in response to CO2 limitation. CA null mutant strains exhibited markedly impaired growth compared to an isogenic wild-type control, suggesting that the CA isoforms have independent, non-redundant roles in M. capsulatus metabolism and physiology. Overexpression of some, but not all, CA isoforms improved bacterial growth kinetics and decreased CO2 evolution from CH4-consuming cultures. Notably, we developed an engineered methanotrophic biocatalyst overexpressing the native α-CA and ß-CA with a 2.5-fold improvement in the conversion of CH4 to biomass. Given that product yield is a significant cost driver of methanotroph-based bioprocesses, the engineered strain developed here could improve the economics of CH4 biocatalysis, including the production of single-cell protein from natural gas or anaerobic digestion-derived biogas.IMPORTANCEMethanotrophs transform CH4 into CO2 and multi-carbon compounds, so they play a critical role in the global carbon cycle and are of interest for biotechnology applications. Some methanotrophs, including Methylococcus capsulatus, can also use CO2 as a carbon source, but this dual one-carbon metabolism is incompletely understood. In this study, we show that M. capsulatus carbonic anhydrases are critical for this bacterium to optimally utilize CO2. We developed an engineered strain with improved CO2 utilization capacity that increased the overall carbon conversion to cell biomass. The improvements to methanotroph-based product yields observed here are expected to reduce costs associated with CH4 conversion bioprocesses.

5.
Animals (Basel) ; 14(16)2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39199963

RESUMO

Due to lack of apex predators in human-dominated landscapes, mesopredator relationships are complex and spatiotemporal niche partitioning strategies can vary, especially when seasonal shifts in resource availability occur. Our objective was to understand spatiotemporal niche overlap across seasons among mesopredators inhabiting a barrier island complex. We placed 19 unbaited cameras throughout Fort De Soto County Park, Florida, USA between February 2021 and July 2023. Of six mesopredator species detected, three species had >75 detections during both the wet and dry seasons (coyote, Canis latrans; Virginia opossum, Didelphis virginiana; and raccoon, Procyon lotor). Using general linear mixed models, we determined that during the wet season coyote-raccoon and raccoon-opossum detections were positively associated with each other (p < 0.05). During the dry season, raccoon-opossum detections were positively associated, and opossums were more likely to be detected around mangroves. After calculating coefficients of overlap, we found all three species varied their temporal activity between seasons. During the dry season exclusively, all three mesopredators occupied different temporal niches. The park's isolated but developed nature has potentially led to a destabilized mesopredator community. Understanding seasonal mesopredator dynamics of Fort De Soto is particularly important because this park supports a high number of nesting shorebirds and sea turtles, which are known food sources for mesopredators.

6.
J Immunol ; 213(7): 988-997, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39140892

RESUMO

Immune cells survey their microenvironment by forming dynamic cellular protrusions that enable chemotaxis, contacts with other cells, and phagocytosis. Podosomes are a unique type of protrusion structured by an adhesive ring of active integrins that surround an F-actin-rich core harboring degradative proteases. Although the features of podosomes, once-established, have been well defined, the steps that lead to podosome formation remain poorly understood by comparison. In this study, we report that spleen tyrosine kinase (Syk) is a critical regulator of podosome formation. Deletion of Syk or targeting its kinase activity eliminated the ability for murine macrophages to form podosomes. We found that the kinase activity of Syk was important for the phosphorylation of its substrates, HS1 and Pyk2, both of which regulate podosome formation. Additionally, before podosomes form, we report that the tandem Src homology 2 domains of Syk afforded multivalent clustering of ITAM-containing adaptors that associated with integrins to structure platforms that initiate podosomes. We therefore propose that Syk has a dual role in regulating podosomes: first, by facilitating the assembly of multivalent signaling hubs that nucleate their formation and second, by sustaining tyrosine kinase activity of the podosomes once they form against their substrates. In cells expressing recently identified gain-of-function variants of SYK, podosomes were dysregulated. These results implicate SYK in the (patho)physiological functions of podosomes in macrophages.


Assuntos
Macrófagos , Podossomos , Quinase Syk , Quinase Syk/metabolismo , Animais , Camundongos , Podossomos/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Fosforilação , Quinase 2 de Adesão Focal/metabolismo , Quinase 2 de Adesão Focal/genética , Camundongos Knockout , Integrinas/metabolismo , Transdução de Sinais , Humanos , Camundongos Endogâmicos C57BL , Quinase 1 de Adesão Focal
7.
bioRxiv ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38979376

RESUMO

Autoreactive B cells play an important but ill-defined role in autoimmune type 1 diabetes (T1D). To better understand their contribution, we performed single cell gene and BCR-seq analysis on pancreatic islet antigen-reactive (IAR) B cells from the peripheral blood of nondiabetic (ND), autoantibody positive prediabetic (AAB), and recent-onset T1D individuals. We found that the frequency of IAR B cells was increased in AAB and T1D. IAR B cells from these donors had altered expression of B cell signaling, pro-inflammatory, infection, and antigen processing and presentation genes. Both AAB and T1D donors demonstrated a significant increase in certain heavy and light chain V genes, and these V genes were enriched in islet-reactivity. Public clones of IAR B cells were restricted almost entirely to AAB and T1D donors. IAR B cells were clonally expanded in the autoimmune donors, particularly the AAB group. Notably, a substantial fraction of IAR B cells in AAB and T1D donors appeared to be polyreactive, which was corroborated by analysis of recombinant monoclonal antibodies. These results expand our understanding of autoreactive B cell activation during T1D and identify unique BCR repertoire changes that may serve as biomarkers for increased disease risk.

8.
Nat Cell Biol ; 26(8): 1247-1260, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38997458

RESUMO

Polymers are endocytosed and hydrolysed by lysosomal enzymes to generate transportable solutes. While the transport of diverse organic solutes across the plasma membrane is well studied, their necessary ongoing efflux from the endocytic fluid into the cytosol is poorly appreciated by comparison. Myeloid cells that employ specialized types of endocytosis, that is, phagocytosis and macropinocytosis, are highly dependent on such transport pathways to prevent the build-up of hydrostatic pressure that otherwise offsets lysosomal dynamics including vesiculation, tubulation and fission. Without undergoing rupture, we found that lysosomes incurring this pressure owing to defects in solute efflux, are unable to retain luminal Na+, which collapses its gradient with the cytosol. This cation 'leak' is mediated by pressure-sensitive channels resident to lysosomes and leads to the inhibition of mTORC1, which is normally activated by Na+-coupled amino acid transporters driven by the Na+ gradient. As a consequence, the transcription factors TFEB/TFE3 are made active in macrophages with distended lysosomes. In addition to their role in lysosomal biogenesis, TFEB/TFE3 activation causes the release of MCP-1/CCL2. In catabolically stressed tissues, defects in efflux of solutes from the endocytic pathway leads to increased monocyte recruitment. Here we propose that macrophages respond to a pressure-sensing pathway on lysosomes to orchestrate lysosomal biogenesis as well as myeloid cell recruitment.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Lisossomos , Macrófagos , Alvo Mecanístico do Complexo 1 de Rapamicina , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Lisossomos/metabolismo , Animais , Macrófagos/metabolismo , Camundongos , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Sódio/metabolismo , Quimiocina CCL2/metabolismo , Quimiocina CCL2/genética , Camundongos Endogâmicos C57BL , Pressão Hidrostática , Humanos , Camundongos Knockout
9.
J Arthroplasty ; 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38914146

RESUMO

BACKGROUND: Modern surgical protocols, particularly the use of tranexamic acid (TXA), have reduced, but not eliminated, blood transfusions surrounding total hip arthroplasty (THA). Identifying patients at risk for transfusion remains important for risk reduction and to determine type and screen testing. METHODS: We reviewed 6,405 patients who underwent primary, unilateral THA between January 2014 and January 2023 at a single academic institution, received TXA, and had preoperative hemoglobin (Hgb) values. We compared demographics, baseline Hgb levels, and surgical details between patients who were and were not transfused. Data were analyzed utilizing multivariate regression and receiver operating characteristic curve analysis. RESULTS: The overall perioperative and intraoperative transfusion rates were 3.4 and 1.0%, respectively. Patients who were older, women, and American Society of Anesthesiologists class >II demonstrated an increased risk of transfusion. Risk of transfusion demonstrated an inverse correlation with preoperative Hgb levels, a bimodal association with body mass index, and a direct correlation with age, surgical time, and estimated blood loss on multivariate analysis. The receiver operating characteristic analysis demonstrated a preoperative Hgb cutoff of 12 g/dL for predicting any transfusion. Above the threshold of 12 g/dL, total and intraoperative transfusions were rare, with rates of 1.7 and 0.3%, respectively. Total and intraoperative transfusion rates with Hgb between 11 and 12 g/dL were 14.3 and 4.6%, respectively. Below 11 g/dL, total and intraoperative transfusion rates were 27.5 and 10.1%, respectively. CONCLUSIONS: In the age of TXA, blood transfusion is rare in THA when preoperative Hgb is >12 g/dL, challenging the need for universal type and screening. Conversely, patients who have Hgb < 11.0 g/dL, remain at substantial risk for transfusion. Between Hgb 11 and 12 g/dL, patient age, sex, body mass index, American Society of Anesthesiologists classification, anticipated estimated blood loss, and surgical time may help predict transfusion risk and the need for a perioperative type and screen. LEVEL OF EVIDENCE: III.

10.
Equine Vet J ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38924597

RESUMO

BACKGROUND: Bisphosphonates are widely used in equine athletes to reduce lameness associated with skeletal disorders. Widespread off-label use has led to concern regarding potential negative effects on bone healing, but little evidence exists to support or refute this. OBJECTIVES: To investigate the influence of clinically relevant doses of tiludronate on bone remodelling and bone healing. STUDY DESIGN: Randomised, controlled in vivo experiments. METHODS: Each horse had a single tuber coxae biopsied (Day 0), then were divided into a treatment (IV tiludronate) or control (IV saline) group. Treatments were administered 30 and 90 days following initial biopsy. Biopsy of the tuber coxae was repeated on Day 60 to evaluate bone healing following a single treatment. Oxytetracycline was administered on Days 137 and 147 to label bone formation. The contralateral tuber coxae was biopsied on Day 150 to evaluate effects of repeated treatment. Bone biopsies were evaluated with micro-computed tomography and/or dynamic histomorphometry using standard techniques. RESULTS: Nineteen horses completed the study, with no complications following the biopsies and treatments. No significant differences in the trabecular bone parameters or bone formation rate were observed between treatment groups. MAIN LIMITATIONS: The use of a first-generation bisphosphonate may mean some effects of these drugs are underrepresented using this model. The results pertain to the tuber coxae and may not reflect injury or the healing response that occurs in long bones in training or racing. CONCLUSIONS: In this model, tiludronate did not affect normal bone remodelling in the horse, despite repeat dosages.

11.
Br J Haematol ; 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38850184

RESUMO

In Australia, bortezomib-based induction (V-IND) is used in >90% of newly diagnosed transplant-eligible multiple myeloma (MM) patients. Four cycles of V-IND with bortezomib-cyclophosphamide-dexamethasone or bortezomib-lenalidomide-dexamethasone are available via the Pharmaceutical Benefits Scheme prior to autologous stem cell transplantation (ASCT). Patients who demonstrate suboptimal response or who are refractory to V-IND demonstrate inferior survival, representing a subgroup of MM where an unmet need persists. We evaluated an early, response-adapted approach in these patients by switching to an intensive sequential therapeutic strategy incorporating daratumumab-lenalidomide-dexamethasone-based (DRd) salvage, high-dose melphalan ASCT followed by DRd consolidation and R maintenance. The overall response rate following four cycles of DRd salvage was 72% (95% credible interval: 57.9-82.4); prespecified, dual, Bayesian proof-of-concept criteria were met. Euro-flow minimal residual disease (MRD) negativity was 46% in the intention-to-treat population and 79% in the evaluable population following 12 cycles of DRd consolidation. At the 24-month follow-up, median progression-free survival and overall survival were not reached. DRd salvage was well tolerated with grade 3 and 4 events reported in 24% and 8% respectively. Response-adapted DRd combined with ASCT achieves high rates of MRD negativity and durable disease control in this functional high-risk group.

12.
bioRxiv ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38798384

RESUMO

The flaviviral NS2B/NS3 protease is a conserved enzyme required for flavivirus replication. Its highly dynamic conformation poses major challenges but also offers opportunities for antiviral inhibition. Here, we established a nanopore tweezers-based platform to monitor NS2B/NS3 conformational dynamics in real-time. Molecular simulations coupled with electrophysiology revealed that the protease could be captured in the middle of the ClyA nanopore lumen, stabilized mainly by dynamic electrostatic interactions. We designed a new Salmonella typhi ClyA nanopore with enhanced nanopore/protease interaction that can resolve the open and closed states at the single-molecule level for the first time. We demonstrated that the tailored ClyA could track the conformational transitions of the West Nile NS2B/NS3 protease and unravel the conformational energy landscape of various protease constructs through population and kinetic analysis. The new ClyA-protease platform paves a way to high-throughput screening strategies for discovering new allosteric inhibitors that target the NS2B and NS3 interface.

13.
Mol Neurobiol ; 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38696065

RESUMO

Heterozygous loss-of-function mutations in the progranulin gene (GRN) are a major cause of frontotemporal dementia due to progranulin haploinsufficiency; complete deficiency of progranulin causes neuronal ceroid lipofuscinosis. Several progranulin-deficient mouse models have been generated, including both knockout mice and knockin mice harboring a common patient mutation (R493X). However, the GrnR493X mouse model has not been characterized completely. Additionally, while homozygous GrnR493X and Grn knockout mice have been extensively studied, data from heterozygous mice is still limited. Here, we performed more in-depth characterization of heterozygous and homozygous GrnR493X knockin mice, which includes biochemical assessments, behavioral studies, and analysis of fluid biomarkers. In the brains of homozygous GrnR493X mice, we found increased phosphorylated TDP-43 along with increased expression of lysosomal genes, markers of microgliosis and astrogliosis, pro-inflammatory cytokines, and complement factors. Heterozygous GrnR493X mice did not have increased TDP-43 phosphorylation but did exhibit limited increases in lysosomal and inflammatory gene expression. Behavioral studies found social and emotional deficits in GrnR493X mice that mirror those observed in Grn knockout mouse models, as well as impairment in memory and executive function. Overall, the GrnR493X knockin mouse model closely phenocopies Grn knockout models. Lastly, in contrast to homozygous knockin mice, heterozygous GrnR493X mice do not have elevated levels of fluid biomarkers previously identified in humans, including neurofilament light chain (NfL) and glial fibrillary acidic protein (GFAP) in both plasma and CSF. These results may help to inform pre-clinical studies that use this Grn knockin mouse model and other Grn knockout models.

14.
J Thromb Haemost ; 22(8): 2294-2305, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38718926

RESUMO

BACKGROUND: Platelets coordinate blood coagulation at sites of vascular injury and play fundamental roles in a wide variety of (patho)physiological processes. Key to many platelet functions is the transport and secretion of proteins packaged within α-granules, organelles produced by platelet precursor megakaryocytes. Prominent among α-granule cargo are fibrinogen endocytosed from plasma and endogenously synthesized von Willebrand factor. These and other proteins are known to require acidic pH for stable packaging. Luminal acidity has been confirmed for mature α-granules isolated from platelets, but direct measurement of megakaryocyte granule acidity has not been reported. OBJECTIVES: To determine the luminal pH of α-granules and their precursors in megakaryocytes and assess the requirement of vacuolar-type adenosine triphosphatase (V-ATPase) activity to establish and maintain the luminal acidity and integrity of these organelles. METHODS: Cresyl violet staining was used to detect acidic granules in megakaryocytes. Endocytosis of fibrinogen tagged with the pH-sensitive fluorescent dye fluorescein isothiocyanate was used to load a subset of these organelles. Ratiometric fluorescence analysis was used to determine their luminal pH. RESULTS: We show that most of the acidic granules detected in megakaryocytes appear to be α-granules/precursors, for which we established a median luminal pH of 5.2 (IQR, 5.0-5.5). Inhibition of megakaryocyte V-ATPase activity led to enlargement of cargo-containing compartments detected by fluorescence microscopy and electron microscopy. CONCLUSION: These observations reveal that V-ATPase activity is required to establish and maintain a luminal acidic pH in megakaryocyte α-granules/precursors, confirming its importance for stable packaging of cargo proteins such as von Willebrand factor.


Assuntos
Grânulos Citoplasmáticos , Megacariócitos , ATPases Vacuolares Próton-Translocadoras , Megacariócitos/metabolismo , Megacariócitos/enzimologia , ATPases Vacuolares Próton-Translocadoras/metabolismo , Concentração de Íons de Hidrogênio , Grânulos Citoplasmáticos/metabolismo , Grânulos Citoplasmáticos/enzimologia , Grânulos Citoplasmáticos/ultraestrutura , Endocitose , Biogênese de Organelas , Fibrinogênio/metabolismo , Animais , Humanos , Fator de von Willebrand/metabolismo , Plaquetas/metabolismo , Plaquetas/enzimologia
15.
Blood ; 144(11): 1183-1192, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-38820590

RESUMO

ABSTRACT: Deficiency of X-linked inhibitor of apoptosis protein (XIAP) is a rare genetic condition that can present with recurrent episodes of hemophagocytic lymphohistiocytosis (HLH), though the exact mechanisms leading to this hyperinflammatory disorder are unclear. Understanding its biology is critical to developing targeted therapies for this potentially fatal disease. Here, we report on a novel multiexonic intragenic duplication leading to XIAP deficiency with recurrent HLH that demonstrated complete response to interleukin (IL)-1ß blockade. We further demonstrate using both primary patient cells and genetically modified THP-1 monocyte cell lines that, contrary to what has previously been shown in mouse cells, XIAP-deficient human macrophages do not produce excess IL-1ß when stimulated under standard conditions. Instead, nucleotide-binding oligomerization domain-like receptor family pyrin domain containing 3 (NLRP3) inflammasome-mediated hyperproduction of IL-1ß is observed only when the XIAP-deficient cells are stimulated under autophagy-promoting conditions and this correlates with defective autophagic flux as measured by decreased accumulation of the early autophagy marker LC3-II. This work, therefore, highlights IL-1ß blockade as a therapeutic option for patients with XIAP deficiency experiencing recurrent HLH and identifies a critical role for XIAP in promoting autophagy as a means of limiting IL-1ß-mediated hyperinflammation during periods of cellular stress.


Assuntos
Autofagia , Interleucina-1beta , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X , Humanos , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/genética , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/deficiência , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo , Interleucina-1beta/metabolismo , Linfo-Histiocitose Hemofagocítica/genética , Linfo-Histiocitose Hemofagocítica/patologia , Linfo-Histiocitose Hemofagocítica/metabolismo , Inflamação/metabolismo , Inflamação/patologia , Inflamação/genética , Inflamassomos/metabolismo , Masculino , Macrófagos/metabolismo , Macrófagos/patologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/deficiência , Feminino
16.
Chem Commun (Camb) ; 60(40): 5298-5301, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38660776

RESUMO

We demonstrate that an ionic liquid 1-ethyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide combined with propylene carbonate and lithium bis(trifluoromethanesulfonyl)imide yields a hybrid electrolyte that enables a wide operational temperature window (-20 °C to 60 °C). When integrated into a lithium titanate‖lithium cobalt oxide full-cell configuration, high-rate capability is achieved at -20 °C with >40% retention at a C/2 cycling rate, and negligible capacity fade is observed during rate capability tests and long-term cycling at 60 °C.

17.
Atherosclerosis ; 395: 117518, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38627162

RESUMO

BACKGROUND AND AIMS: There are a limited number of pharmacologic therapies for coronary artery disease, and few rodent models of occlusive coronary atherosclerosis and consequent myocardial infarction with which one can rapidly test new therapeutic approaches. Here, we characterize a novel, fertile, and easy-to-use HDL receptor (SR-B1)-based model of atherogenic diet-inducible, fatal coronary atherosclerosis, the SR-B1ΔCT/LDLR KO mouse. Additionally, we test intramyocardial injection of Stromal Cell-Derived Factor-1 alpha (SDF-1α), a potent angiogenic cytokine, as a possible therapy to rescue cardiac function in this mouse. METHODS: SR-B1ΔCT/LDLR KO mice were fed the Paigen diet or standard chow diet, and we determined the effects of the diets on cardiac function, histology, and survival. After two weeks of feeding either the Paigen diet (n = 24) or standard chow diet (n = 20), the mice received an intramyocardial injection of either SDF-1α or phosphate buffered saline (PBS). Cardiac function and angiogenesis were assessed two weeks later. RESULTS: When six-week-old mice were fed the Paigen diet, they began to die as early as 19 days later and 50% had died by 38 days. None of the mice maintained on the standard chow diet died by day 72. Hearts from mice on the Paigen diet showed evidence of cardiomegaly, myocardial infarction, and occlusive coronary artery disease. For the five mice that survived until day 28 that underwent an intramyocardial injection of PBS on day 15, the average ejection fraction (EF) decreased significantly from day 14 (the day before injection, 52.1 ± 4.3%) to day 28 (13 days after the injection, 30.6 ± 6.8%) (paired t-test, n = 5, p = 0.0008). Of the 11 mice fed the Paigen diet and injected with SDF-1α on day 15, 8 (72.7%) survived to day 28. The average EF for these 8 mice increased significantly from 48.2 ± 7.2% on day 14 to63.6 ± 6.9% on day 28 (Paired t-test, n = 8, p = 0.003). CONCLUSIONS: This new mouse model and treatment with the promising angiogenic cytokine SDF-1α may lead to new therapeutic approaches for ischemic heart disease.


Assuntos
Quimiocina CXCL12 , Doença da Artéria Coronariana , Modelos Animais de Doenças , Camundongos Knockout , Receptores de LDL , Receptores Depuradores Classe B , Animais , Quimiocina CXCL12/metabolismo , Quimiocina CXCL12/genética , Receptores de LDL/genética , Receptores de LDL/deficiência , Receptores Depuradores Classe B/genética , Masculino , Neovascularização Fisiológica/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Dieta Aterogênica , Camundongos , Função Ventricular Esquerda , Miocárdio/patologia , Miocárdio/metabolismo , Dieta Hiperlipídica
18.
Synth Syst Biotechnol ; 9(2): 250-258, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38435708

RESUMO

Methanotrophic bacteria are currently used industrially for the bioconversion of methane-rich natural gas and anaerobic digestion-derived biogas to valuable products. These bacteria may also serve to mitigate the negative effects of climate change by capturing atmospheric greenhouse gases. Several genetic tools have previously been developed for genetic and metabolic engineering of methanotrophs. However, the available tools for use in methanotrophs are significantly underdeveloped compared to many other industrially relevant bacteria, which hinders genetic and metabolic engineering of these biocatalysts. As such, expansion of the methanotroph genetic toolbox is needed to further our understanding of methanotrophy and develop biotechnologies that leverage these unique microbes for mitigation and conversion of methane to valuable products. Here, we determined the copy number of three broad-host-range plasmids in Methylococcus capsulatus Bath and Methylosinus trichosporium OB3b, representing phylogenetically diverse Gammaproteobacterial and Alphaproteobacterial methanotrophs, respectively. Further, we show that the commonly used synthetic Anderson series promoters are functional and exhibit similar relative activity in M. capsulatus and M. trichosporium OB3b, but the synthetic series had limited range. Thus, we mutagenized the native M. capsulatus particulate methane monooxygenase promoter and identified variants with activity that expand the activity range of synthetic, constitutive promoters functional not only in M. capsulatus, but also in Escherichia coli. Collectively, the tools developed here advance the methanotroph genetic engineering toolbox and represent additional synthetic genetic parts that may have broad applicability in Pseudomonadota bacteria.

19.
J Pers Med ; 14(3)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38541029

RESUMO

Molecular imaging is a key tool in the diagnosis and treatment of prostate cancer (PCa). Magnetic Resonance (MR) plays a major role in this respect with nuclear medicine imaging, particularly, Prostate-Specific Membrane Antigen-based, (PSMA-based) positron emission tomography with computed tomography (PET/CT) also playing a major role of rapidly increasing importance. Another key technology finding growing application across medicine and specifically in molecular imaging is the use of machine learning (ML) and artificial intelligence (AI). Several authoritative reviews are available of the role of MR-based molecular imaging with a sparsity of reviews of the role of PET/CT. This review will focus on the use of AI for molecular imaging for PCa. It will aim to achieve two goals: firstly, to give the reader an introduction to the AI technologies available, and secondly, to provide an overview of AI applied to PET/CT in PCa. The clinical applications include diagnosis, staging, target volume definition for treatment planning, outcome prediction and outcome monitoring. ML and AL techniques discussed include radiomics, convolutional neural networks (CNN), generative adversarial networks (GAN) and training methods: supervised, unsupervised and semi-supervised learning.

20.
Sleep Health ; 10(3): 321-326, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38548566

RESUMO

INTRODUCTION: Insomnia symptoms are associated with poor physical and mental health. Exercise is associated with good sleep while sedentary behavior is associated with poor sleep. This study investigated the longitudinal, dynamic associations among exercise, sedentary behavior, and insomnia symptoms. METHODS: Seven hundred and fifty-six adults (Mage=47.2years, 54.9% female) took part in an online longitudinal study investigating sleep and health across the lifespan. Participants reported duration of moderate-to-strenuous exercise, percentage of day spent sitting, and insomnia symptoms (Insomnia Severity Index [ISI]). The ISI was scored as a total score and two-factor scores: (1) Sleep Disturbance (items 1, 2, 3) and (2) Daytime Dysfunction (items 4, 5, 6, 7). Multilevel modeling was used to examine the typical (i.e., between-persons) and individual (i.e., within-persons) associations among sedentary behavior, exercise, and insomnia symptoms. RESULTS: Sedentary behavior was significantly associated with total ISI scores at both the between-person and within-person levels (ß = 0.036, t = 3.23, p = .001; ß = 0.014, t = 1.99, p = .048). Both between-persons and within-person levels of sedentary behavior were associated with Daytime Dysfunction (ß = 0.028, t = 3.79, p < .001; ß = 0.009, t = 2.08, p = .039). Exercise was associated with total ISI and Daytime Dysfunction scores at the between-persons level but not at the within-persons level (ß = 0.028, t = 2.57, p = .01; ß = -0.002, t = -3.02, p = .003). CONCLUSIONS: Sedentary behavior was a more consistent and robust predictor of insomnia symptoms than exercise. The association between sedentary behavior and insomnia symptoms was dynamic in that when an individual reported being more sedentary than their norm, they also reported more insomnia symptoms. Future analyses should examine potential moderator variables and comorbid conditions.


Assuntos
Exercício Físico , Comportamento Sedentário , Autorrelato , Distúrbios do Início e da Manutenção do Sono , Humanos , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Feminino , Masculino , Estudos Longitudinais , Pessoa de Meia-Idade , Adulto , Idoso , Sono
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