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2.
J Am Med Dir Assoc ; : 105293, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39366668

RESUMO

OBJECTIVES: Patients with immune-mediated rheumatic diseases (IMRDs) often exhibit reduced muscle strength. Therefore, this review aimed to evaluate patients with muscle strength IMRDs compared with healthy control patients and to summarize the relationship between low muscle strength and clinical features in patients with IMRDs. DESIGN: Systematic review with meta-analysis of case-control studies. SETTING AND PARTICIPANTS: Patients with IMRDs. METHODS: A comprehensive search was conducted in the Embase, MEDLINE, Web of Science, and Cochrane databases to identify relevant studies published up to November 2023 in rheumatoid arthritis, systemic lupus erythematosus, systemic sclerosis, and spondyloarthritis. Meta-analysis was performed using a random-effects model to verify the mean difference (MD) muscle strength between patients with IMRDs and an age- and sex-matched healthy group. RESULTS: We identified 11,692 studies, and 760 studies were selected for screening. Ultimately, 26 studies met the inclusion criteria, composed of 2661 individuals, mostly women. The IMRDs women group had lower handgrip muscle strength (MD, -9.53; 95% CI, -11.78 to -7.28 kg) than the healthy group, whereas the handgrip strength men groups did not differ significantly from that of the healthy group. Similar trend was observed in lower limb muscle strength for the IMRDs women group than the healthy group (MD, -63.10; 95% CI, -94.18 to -32.01 Nm). Four studies examined muscle strength and clinical features in rheumatoid arthritis: one associated it with age and disease activity, 2 associated it with disease duration, and 3 associated it with physical function. In systemic lupus erythematosus, only 2 studies associated low muscle strength with age, disease activity, and fatigue. No associations were found in spondyloarthritis, and none were found in systemic sclerosis. CONCLUSIONS AND IMPLICATIONS: Patients with IMRD exhibit lower muscle strength than healthy counterparts, with low strength moderately associated with longer disease duration, worsening disease activity, and decline in physical function. Targeted interventions are crucial for preventing and managing muscle weakness in IMRDs.

3.
Front Microbiol ; 15: 1464720, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39376708

RESUMO

Introduction: Chagas disease is a neglected tropical disease caused by the parasite Trypanosoma cruzi that is transmitted mainly by the feces of infected Triatomines. In Ecuador the main vector is Rhodnius ecuadoriensis which is distributed in several provinces of the country. More than 40% of these insects in the wild have T. cruzi as part of their intestinal microbiota. For this reason, the objective of this research was to characterize the intestinal bacterial microbiota of R. ecuadoriensis. Methods: The methodology used was based on the DNA extraction of the intestinal contents from the wild collected insects (adults and nymphs V), as well as the insects maintained at the insectary of the CISeAL. Finally, the samples were analyzed by metagenomics extensions based on the different selected criteria. Results: The intestinal microbiota of R. ecuadoriensis presented a marked divergence between laboratory-raised and wild collected insects. This difference was observed in all stages and was similar between insects from Loja and Manabí. A large loss of microbial symbionts was observed in laboratory-raised insects. Discussion: This study is a crucial first step in investigating microbiota interactions and advancing new methodologies.

4.
World J Hepatol ; 16(9): 1211-1228, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39351515

RESUMO

Extracellular vesicles (EVs) are small particles released by many cell types in different tissues, including the liver, and transfer specific cargo molecules from originating cells to receptor cells. This process generally culminates in activation of distant cells and inflammation and progression of certain diseases. The global chronic liver disease (CLD) epidemic is estimated at 1.5 billion patients worldwide. Cirrhosis and liver cancer are the most common risk factors for CLD. However, hepatitis C and B virus infection and obesity are also highly associated with CLD. Nonetheless, the etiology of many CLD pathophysiological, cellular, and molecular events are unclear. Changes in hepatic lipid metabolism can lead to lipotoxicity events that induce EV release. Here, we aimed to present an overview of EV features, from definition to types and biogenesis, with particular focus on the molecules related to steatosis-related liver disease, diagnosis, and therapy.

5.
Mayo Clin Proc Innov Qual Outcomes ; 8(5): 443-450, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39263427

RESUMO

Transgender and gender diverse (TGD) people experience disparities in cancer care, including more late-stage diagnoses, worse cancer-related outcomes, and an increased number of unaddressed and more severe symptoms related to cancer and cancer-directed therapy. This article outlines plans to address the unique needs of TGD people through a TGD-focused oncology clinic. Such a clinic could be structured by upholding the following tenets: (1) champion a supportive, gender-affirming environment that seeks to continuously improve, (2) include a transdisciplinary team of specialists who are dedicated to TGD cancer care, and (3) initiate and embrace TGD-patient-centric research on health outcomes and health care delivery.

6.
Sensors (Basel) ; 24(17)2024 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-39275408

RESUMO

Precise measurement of fiber diameter in animal and synthetic textiles is crucial for quality assessment and pricing; however, traditional methods often struggle with accuracy, particularly when fibers are densely packed or overlapping. Current computer vision techniques, while useful, have limitations in addressing these challenges. This paper introduces a novel deep-learning-based method to automatically generate distance maps of fiber micrographs, enabling more accurate fiber segmentation and diameter calculation. Our approach utilizes a modified U-Net architecture, trained on both real and simulated micrographs, to regress distance maps. This allows for the effective separation of individual fibers, even in complex scenarios. The model achieves a mean absolute error (MAE) of 0.1094 and a mean square error (MSE) of 0.0711, demonstrating its effectiveness in accurately measuring fiber diameters. This research highlights the potential of deep learning to revolutionize fiber analysis in the textile industry, offering a more precise and automated solution for quality control and pricing.

7.
Animals (Basel) ; 14(17)2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39272315

RESUMO

Porcine reproductive and respiratory syndrome virus (PRRSV) is a globally significant pathogen of pigs. Preventing the entry of PRRSV into swine breeding herds enhances animal health and welfare. A recently published retrospective cohort study reported significant differences in PRRSV incidence risk between breeding herds that practiced Next Generation Biosecurity (NGB) COMPLETE, versus herds that practiced a partial approach (NGB INCOMPLETE) over a 2-year period. This follow-up communication builds on this previous publication and brings new information regarding statistical differences in key performance indicators (KPIs) from 43 NGB COMPLETE herds and 19 NGB INCOMPLETE herds during disease years 1 and 2. Statistically significant differences included higher total born/farrow and pigs weaned/female along with a reduced pre-weaning mortality and wean to 1st service interval, as well as a 0.91 increase in the number of pigs weaned/mated female/year. In addition, this communication reports that PRRSV incidence risk throughout disease years 1-3 was 8.0%, and that the association of NGB status (COMPLETE vs. INCOMPLETE) and disease burden for the cumulative 3-year period was statistically significant (p < 0.0001). These findings support previously published data that NGB, while not perfect, provides sustainable prevention of PRRSV, and may help improve herd productivity.

8.
Mol Neurobiol ; 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39313656

RESUMO

The abuse of synthetic steroids, such as nandrolone decanoate (ND), is often associated with violent behavior, increasing the risk of traumatic brain injury (TBI). After a TBI, proteins like APP, ß-amyloid peptide-42 (Aß42), and phosphorylated tau (pTau) accumulate and trigger endoplasmic reticulum (ER) stress associated with an unfolded protein response (UPR). The involvement of mitochondrial bioenergetics in this context remains unexplored. We interrogate whether the abuse of ND before TBI alters the responses of ER stress and mitochondrial bioenergetics in connection with neurodegeneration and memory processing in mice. Male CF1 adult mice were administered ND (15 mg/kg) or vehicle (VEH) s.c. for 19 days, coinciding with the peak day of aggressive behavior, and then underwent cortical controlled impact (CCI) or sham surgery. Spatial memory was assessed through the Morris water maze task (MWM) post-TBI. In synaptosome preparations, i) we challenged mitochondrial complexes (I, II, and V) in a respirometry assay, employing metabolic substrates, an uncoupler, and inhibitors; and ii) assessed molecular biomarkers through Western blot. TBI significantly increased APP, Aß42, and pTauSer396 levels, along with ER-stress proteins, GRP78, ATF6, and CHOP, implying it primed apoptotic signaling. Concurrently, TBI reduced mitochondrial Ca2+ efflux in exchange with Na+, disturbed the formation/dissipation of membrane potential, increased H2O2 production, decreased biogenesis (PGC-1⍺ and TOM20), and ATP biosynthesis coupled with oxygen consumption. Unexpectedly, ND abuse before TBI attenuated the elevations in APP, Aß42, and pTauSer396, accompanied by a decrease in GRP78, ATF6, and CHOP levels, and partial normalization of mitochondrial-related endpoints. A principal component analysis revealed a key hierarchical signature featuring mitochondrial Ca2+ efflux, CHOP, GRP78, TOM20, H2O2, and bioenergetic efficiency as a unique variable (PC1) able to explain the memory deficits caused by TBI, as well as the preservation of memory fitness induced by prior ND abuse.

9.
Front Plant Sci ; 15: 1429976, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39315379

RESUMO

Alfalfa biomass can be fractionated into leaf and stem components. Leaves comprise a protein-rich and highly digestible portion of biomass for ruminant animals, while stems constitute a high fiber and less digestible fraction, representing 50 to 70% of the biomass. However, little attention has focused on stem-related traits, which are a key aspect in improving the nutritional value and intake potential of alfalfa. This study aimed to identify molecular markers associated with four morphological traits in a panel of five populations of alfalfa generated over two cycles of divergent selection based on 16-h and 96-h in vitro neutral detergent fiber digestibility in stems. Phenotypic traits of stem color, presence of stem pith cells, winter standability, and winter injury were modeled using univariate and multivariate spatial mixed linear models (MLM), and the predicted values were used as response variables in genome-wide association studies (GWAS). The alfalfa panel was genotyped using a 3K DArTag SNP markers for the evaluation of the genetic structure and GWAS. Principal component and population structure analyses revealed differentiations between populations selected for high- and low-digestibility. Thirteen molecular markers were significantly associated with stem traits using either univariate or multivariate MLM. Additionally, support vector machine (SVM) and random forest (RF) algorithms were implemented to determine marker importance scores for stem traits and validate the GWAS results. The top-ranked markers from SVM and RF aligned with GWAS findings for solid stem pith, winter standability, and winter injury. Additionally, SVM identified additional markers with high variable importance for solid stem pith and winter injury. Most molecular markers were located in coding regions. These markers can facilitate marker-assisted selection to expedite breeding programs to increase winter hardiness or stem palatability.

10.
Biotechnol Prog ; : e3510, 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39324859

RESUMO

Healthcare-associated infections (HAIs) pose significant challenges to global health due to pathogen complexity and antimicrobial resistance. Biosensors utilizing antimicrobial peptides offer innovative solutions. Hylarana picturata Multiple Active Peptide 1 (Hp-MAP1), derived from Temporin-PTA, exhibits antibacterial properties sourced from the skin secretions of the Malaysian fire-bellied frog. An innovative sensing layer was developed for the electrochemical biorecognition of diverse pathogens: Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, and Staphylococcus aureus. Electrochemical impedance spectroscopy differentiated microorganisms based on distinct electrochemical responses. The sensor layer, composed of functionalized multi-walled carbon nanotubes (MWCNTs) associated with Hp-MAP1, exhibited varying levels of charge transfer resistance (RCT) for different microorganisms. Gram-negative species, especially P. aeruginosa, displayed higher RCT values, indicating better impedimetric responses. Excellent LODs were observed for P. aeruginosa (0.60), K. pneumoniae (0.42), E. coli (0.67), and S. aureus (0.59), highlighting the efficacy of the MWCNTs/Hp-MAP1 biosensor in microbial identification. The MWCNTs/Hp-MAP1 biosensor platform presents a promising and effective microbial identification strategy with potential healthcare applications to mitigate HAIs and enhance patient care.

11.
Am J Infect Control ; 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39277036

RESUMO

BACKGROUND: We aimed to determine the prevalence of genes associated with high-level mupirocin and biocide resistance in methicillin-resistant Staphylococcus aureus (MRSA) isolates among hospitalized patients and to characterize their genomic and epidemiologic features. METHODS: Study conducted on an integrated health system. Clinical cultures with MRSA from hospitalized patients collected between March 1, 2023, and January 20, 2024 underwent prospective whole-genome sequencing, including assessment for the presence of markers of resistance against mupirocin (mupA) and biocides (qac). Demographic and clinical characteristics were reviewed. RESULTS: We analyzed 463 MRSA isolates. The overall prevalence of mupA(+), qacA(+), and qacC(+) genes was 22.0%, 2.4%, and 19.0%, respectively. Most mupA(+) isolates belonged to ST8, but ST8732 (a novel variant of ST8) had the highest prevalence of mupA(+) isolates at 95%. Patients mupA(+) were older, and none of the isolates from pediatric patients harbored this gene. DISCUSSION: Through prospective whole-genome sequencing of MRSA isolates, we detected a prevalence of genes conferring mupirocin resistance considerably higher than previously reported, particularly among MRSA ST8 variants. CONCLUSIONS: Our findings highlight the need for monitoring resistance to agents used for the prevention of S aureus infections, as these trends have implications for infection prevention programs and public health at large.

12.
Protein Sci ; 33(10): e5182, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39324667

RESUMO

Fold-switching enables metamorphic proteins to reversibly interconvert between two highly dissimilar native states to regulate their protein functions. While about 100 proteins have been identified to undergo fold-switching, unveiling the key residues behind this mechanism for each protein remains challenging. Reasoning that fold-switching in proteins is driven by dynamic changes in local energetic frustration, we combined fold-switching simulations generated using simplified structure-based models with frustration analysis to identify key residues involved in this process based on the change in the density of minimally frustrated contacts during refolding. Using this approach to analyze the fold-switch of the bacterial transcription factor RfaH, we identified 20 residues that significantly change their frustration during its fold-switch, some of which have been experimentally and computationally reported in previous works. Our approach, which we developed as an additional module for the FrustratometeR package, highlights the role of local frustration dynamics in protein fold-switching and offers a robust tool to enhance our understanding of other proteins with significant conformational shifts.


Assuntos
Proteínas de Escherichia coli , Dobramento de Proteína , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/metabolismo , Transativadores/química , Transativadores/metabolismo , Transativadores/genética , Simulação de Dinâmica Molecular , Fatores de Alongamento de Peptídeos/química , Fatores de Alongamento de Peptídeos/metabolismo , Modelos Moleculares , Conformação Proteica , Termodinâmica
13.
Bioengineering (Basel) ; 11(9)2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39329647

RESUMO

Chronic pain affects over 50 million people in the United States, particularly older adults, making effective assessment and treatment essential in primary care. Actigraphy, which monitors and records limb movement to estimate wakefulness and sleep, has emerged as a valuable tool for assessing pain by providing insights into activity patterns. This review highlights the non-invasive, cost-effective nature of actigraphy in pain monitoring, along with its ability to offer continuous, detailed data on patient movement. However, actigraphy's reliance on physical activity as a proxy for pain, and its inability to directly measure pain intensity, limit its applicability to certain pain types, such as neuropathic pain. Further research is needed to overcome these limitations and to improve the effectiveness of actigraphy in diverse clinical settings.

14.
Porcine Health Manag ; 10(1): 34, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39334499

RESUMO

BACKGROUND: During the fall of 2020, the porcine reproductive and respiratory syndrome virus (PRRSV) L1C.5 variant emerged and rapidly spread throughout southern Minnesota generating questions regarding possible transmission routes. This study aimed to investigate whether PRRSV could be detected on surfaces inside and outside pig barns housing L1C.5 variant PRRSV-positive pigs to illustrate the potential for indirect transmission of PRRSV. Seven Midwestern U.S. PPRS-positive breeding or growing pig farms and one PRRS-negative farm were conveniently selected. Internal and external barn surfaces were wiped using a PBS moistened cloth and the resulting liquid was submitted to the University of Minnesota Veterinary Diagnostic Laboratory for PRRSV RT-PCR testing and virus isolation. RESULTS: All (n = 26) samples from PRRSV-negative farm tested negative. Nineteen (13%) out of 143 samples from positive farms yielded positive RT-PCR results. Positive samples originated primarily from exhaust fan cones and doorknobs, followed by anteroom floor and mortality carts/sleds. Virus isolation attempted on two samples did not yield positive results. CONCLUSIONS: PRRSV contamination can occur on surfaces inside and outside pig barns that are in frequent contact with farm personnel. Although virus isolation attempts were negative, our results illustrate the potential for PRRSV to be transmitted indirectly through contaminated materials or farm personnel. The study supports the implementation of biosecurity practices by farm personnel to prevent the introduction of PRRSV into farms and the prevention of PRRSV transmission between farms.

15.
Biology (Basel) ; 13(9)2024 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-39336084

RESUMO

Considering a circular economy perspective, this study evaluates the possible effect of targeted short-term supplementation with Withania somnifera L. (WS; Ashwagandha) on ram's seminal quality, socio-sexual behaviors, and blood constituents. Black Belly rams (n = 20) received a basal diet comprising feed-leftovers from dairy cows in the north-arid Mexico (i.e., Comarca Lagunera CL). The experimental units, with proven libido and fertility, were homogeneous in terms of age (3.41 ± 0.21 yr.), live weight (LW; 53.8 ± 3.3 kg), body condition (BC; 2.96 ± 0.01 units), initial sperm concentration (2387 ± 804 × 106), and viability (23.9 ± 15.6%). Rams were randomly assigned during the transition reproductive period (i.e., May to Jun; 25° NL) to three treatment groups: non-supplemented control group (CONT; n = 6), low WS-supplemented (LWS; i.e., 100 mg kg LW-1 d-1 × 40 d; n = 7), and high-WS-supplemented (HWS; i.e., 200 mg kg LW-1 d-1 × 40 d; n = 7). The basal leftover diet was offered twice daily (0700 and 1600 h); the experimental period (EP) lasted 47 d. No differences (p > 0.05) among treatments occurred regarding LW and BCS at the onset of the EP. Whereas the greater scrotal circumference (SCRC, cm) arose in the LWS and CONT rams, an increased ejaculated volume (VOLEJA, mL) occurred in the WS-rams. A total of 5/9 (i.e., 55%) appetitive and 3/3 (i.e., 100%) consummatory sexual behaviors favored (p < 0.05) the WS-rams, particularly the HWS rams, towards the final EP. The same was true (p < 0.05) regarding the hemogram variables white blood cell count (×109 cells L-1), hemoglobin concentration (g dL-1), and medium corpuscular volume (fL). This study, based on a rethink-reuse-reduce enquiry approach, enabled connectedness between two noteworthy animal systems in the CL: dairy cows and meat sheep schemes. Certainly, the use of dairy cow feed-leftovers aligned with the short-term supplementation with WS promoted enhanced testicular function, augmented seminal volume, and an increased sexual behavior in Black Belly rams in northern Mexico. Finally, while our research outcomes should enhance not only the resilience and sustainability of sheep production and the well-being of sheep-producers and their families, it may also embrace clinical translational applications.

16.
Eur Spine J ; 2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39305301

RESUMO

PURPOSE: The value of adding fusion to decompression surgery for lumbar degenerative spondylolisthesis and spinal canal stenosis remains debated. Therefore, the comparative effectiveness and selected healthcare resource utilization of patients undergoing decompression with or without fusion surgery at 3 years follow-up was assessed. METHODS: Using observational data from the Lumbar Stenosis Outcome Study and a target trial emulation with index trial benchmarking approach, our study assessed the comparative effectiveness of the two main surgical interventions for lumbar degenerative spondylolisthesis-fusion and decompression alone in patients with lumbar degenerative spondylolisthesis and spinal canal stenosis. The primary outcome-measure was change in health-related quality of life (EuroQol Health Related Quality of Life 5-Dimension 3-Level questionnaire [EQ-5D-3L]); secondary outcome measures were change in back/leg pain intensity (Numeric Rating Scale), change in satisfaction (Spinal Stenosis Measure satisfaction subscale), physical therapy and oral analgesic use (healthcare utilization). RESULTS: 153 patients underwent decompression alone and 62 had decompression plus fusion. After inverse probability weighting, 137 patients were included in the decompression alone group (mean age, 73.9 [7.5] years; 77 female [56%]) and 36 in the decompression plus fusion group (mean age, 70.1 [6.7] years; 18 female [50%]). Our findings were compatible with no standardized mean differences in EQ-5D-3L summary index change score at 3 years (EQ-5D-3L German: 0.07 [95% confidence interval (CI), - 0.25 to 0.39]; EQ-5D-3L French: 0.18 [95% CI, - 0.14 to 0.50]). No between-group differences in change in back/leg pain intensity or satisfaction were found. Decompression plus fusion was associated with greater physical therapy utilization at 3 years follow-up. CONCLUSION: Decompression alone should be considered the primary option for patients with lumbar degenerative spondylolisthesis and spinal stenosis.

17.
RSC Adv ; 14(41): 29910-29918, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39301235

RESUMO

During attempts to synthesize zirconium-based MOFs, we have obtained a new crystal structure of the cluster with Zr6O8 core and formula unit [Zr6O4(OH)4(OH2)8(CH3COO)4(SO4)4]·nH2O. Unlike other systems, mild conditions were employed in this case; no strong acids or hydrothermal conditions were required. The molecular assembly in the crystal is characterized by strong O-H⋯O hydrogen bonds connecting neighboring molecules, allowing the formation of a three-dimensional maze of tunnels with H2O molecules stabilizing the framework. Noteworthy, at 100 °C, the strong Zr6O8 core and the O-H⋯O hydrogen bonds help form a system where the molecular cluster is conserved, but the long-range order is lost. FT-IR, Raman, TGA, DSC, and X-ray diffraction techniques were used to characterize the title compound.

18.
Antimicrob Agents Chemother ; : e0089824, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39345182

RESUMO

The cefazolin inoculum effect (CzIE) has been associated with poor clinical outcomes in patients with methicillin-susceptible Staphylococcus aureus (MSSA) infections. We aimed to investigate the point prevalence of the CzIE among nasal colonizing MSSA isolates from ICU patients in a multicenter study in Colombia (2019-2023). Patients underwent nasal swabs to assess for S. aureus colonization on admission to the ICU, and some individuals had follow-up swabs. We performed cefazolin MIC by broth microdilution using standard and high inoculum and developed a modified nitrocefin-based rapid test to detect the CzIE. Whole-genome sequencing was carried out to characterize BlaZ types and allotypes, phylogenomics, and Agr-typing. A total of 352 patients were included; 46/352 (13%) patients were colonized with S. aureus and 22% (10/46) and 78% (36/46) with MRSA and MSSA, respectively. Among 36 patients who contributed with 43 MSSA colonizing isolates, 21/36 (58%) had MSSA exhibiting the CzIE. BlaZ type A and BlaZ-2 were the predominant type and allotype in 56% and 52%, respectively. MSSA belonging to CC30 were highly associated with the CzIE, and single-nucleotide polymorphism (SNP) analyses supported possible transmission of MSSA exhibiting the CzIE among some patients of the same unit. The modified nitrocefin rapid test had 100%, 94.4%, and 97.7% sensitivity, specificity, and accuracy, respectively. We found a high point prevalence of the CzIE in MSSA colonizing the nares of critically ill patients in Colombia. A modified rapid test was highly accurate in detecting the CzIE in this patient population.

19.
bioRxiv ; 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39345602

RESUMO

Background: Renal autoregulatory mechanisms modulate renal blood flow. Connecting tubule glomerular feedback (CNTGF) is a vasodilator mechanism in the connecting tubule (CNT), triggered paracrinally when high sodium levels are detected via the epithelial sodium channel (ENaC). The primary activation factor of CNTGF-whether NaCl concentration, independent luminal flow, or the combined total sodium delivery-is still unclear. We hypothesized that increasing luminal flow in the CNT induces CNTGF via O2 - generation and ENaC activation. Methods: Rabbit afferent arterioles (Af-Arts) with adjacent CNTs were microperfused ex-vivo with variable flow rates and sodium concentrations ranging from <1 mM to 80 mM and from 5 to 40 nL/min flow rates. Results: Perfusion of the CNT with 5 mM NaCl and increasing flow rates from 5 to 10, 20, and 40 nL/min caused a flow rate-dependent dilation of the Af-Art (p<0.001). Adding the ENaC blocker benzamil inhibited flow-induced Af-Art dilation, indicating a CNTGF response. In contrast, perfusion of the CNT with <1 mM NaCl did not result in flow-induced CNTGF vasodilation (p>0.05). Multiple linear regression modeling (R 2 =0.51;p<0.001) demonstrated that tubular flow (ß=0.163 ± 0.04;p<0.001) and sodium concentration (ß=0.14 ± 0.03;p<0.001) are independent variables that induce afferent arteriole vasodilation. Tempol reduced flow-induced CNTGF, and L-NAME did not influence this effect. Conclusion: Increased luminal flow in the CNT induces CNTGF activation via ENaC, partially due to flow-stimulated O2-production and independent of nitric oxide synthase (NOS) activity.

20.
Nat Commun ; 15(1): 8416, 2024 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-39341835

RESUMO

Hypoxia occurs in 90% of solid tumors and is associated with metastasis and mortality. Breast cancer cells that experience intratumoral hypoxia are 5x more likely to develop lung metastasis in animal models. Using spatial transcriptomics, we determine that hypoxic cells localized in more oxygenated tumor regions (termed 'post-hypoxic') retain expression of hypoxia-inducible and NF-kB-regulated genes, even in the oxygen-rich bloodstream. This cellular response is reproduced in vitro under chronic hypoxic conditions followed by reoxygenation. A subset of genes remains increased in reoxygenated cells. MUC1/MUC1-C is upregulated by both HIF-1α and NF-kB-p65 during chronic hypoxia. Abrogating MUC1 decreases the expression of superoxide dismutase enzymes, causing reactive oxygen species (ROS) production and cell death. A hypoxia-dependent genetic deletion of MUC1, or MUC1-C inhibition by GO-203, increases ROS levels in circulating tumor cells (CTCs), reducing the extent of metastasis. High MUC1 expression in tumor biopsies is associated with recurrence, and MUC1+ CTCs have lower ROS levels than MUC1- CTCs in patient-derived xenograft models. This study demonstrates that therapeutically targeting MUC1-C reduces hypoxia-driven metastasis.


Assuntos
Neoplasias da Mama , Mucina-1 , Espécies Reativas de Oxigênio , Mucina-1/metabolismo , Mucina-1/genética , Humanos , Animais , Espécies Reativas de Oxigênio/metabolismo , Feminino , Linhagem Celular Tumoral , Camundongos , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Células Neoplásicas Circulantes/metabolismo , Células Neoplásicas Circulantes/patologia , Neoplasias Pulmonares/secundário , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Oxigênio/metabolismo , Fator de Transcrição RelA/metabolismo , Metástase Neoplásica , Hipóxia/metabolismo , Hipóxia Celular
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