Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 542
Filtrar
1.
Pathol Res Pract ; 260: 155444, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38986361

RESUMEN

Lung cancer is still a global health challenge in terms of high incidence, morbidity, and mortality. Recent scientific studies have determined that pyroptosis, a highly inflammatory form of programmed cell death, can be identified as a potential lung cancer therapeutic target. The NLRP3 inflammasome acts as a critical mediator in this process and, upon activation, activates multiprotein complex formation as well as caspase-1 activation. This process, triggered by a release of pro-inflammatory cytokines, results in pyroptotic cell death. Also, the relationship between the NLRP3 inflammasome and lung cancer was justified by its influence on tumour growth or metastasis. The molecular pathways produce progenitive mediators and remake the tissue. Finally, targeting NLRP3 inflammasome for pyroptosis induction and inhibition of its activation appears to be a promising lung cancer treatment approach. This technique makes cancer treatment more promising and personalized. This review explores the role of NLRP3 inflammasome activation and its possibilities in lung cancer treatment.

2.
Artículo en Inglés | MEDLINE | ID: mdl-38995610

RESUMEN

Abiraterone acetate (ABA), a biopharmaceutical class IV drug suffers from solubility and permeability pitfalls resulting in limited oral bioavailability and positive food effect, i.e. multi-fold enhancement in drug absorption in the presence of food. This poses difficulties to physicians towards the estimation of dose and dosage regimen required for efficacious therapy of prostate cancer (PCa). Nanostructured lipid carriers (NLC) have demonstrated tremendous outcomes in enhancing the oral bioavailability of various entities along with food effect attenuation. In this study, Quality by design and multivariate analysis was employed for optimization of ABA loaded NLC (ABA NLC). The optimal size, PDI and zeta potential obtained using QbD were 134.6 nm, 0.163 and -15.7 mV respectively. Ex vivo qualitative and quantitative intestinal permeability studies demonstrated improved traversion of NLC through the intestinal segments. In vitro dissolution profile in biorelevant fast and fed gastric and intestinal media revealed minimal differences for ABA NLC compared to ABA. In vivo pharmacokinetics was performed to decipher the efficacy of ABA NLC in mitigating the food effect of ABA. The studies demonstrated 14.51-fold and 1.94-fold improvement in oral bioavailability during fasted and fed state respectively as compared to free ABA. The absorption mechanism of ABA NLC using chylomicron flow blocking approach conveyed lymphatic uptake as the major mechanism. Cmax fast/fed ratio was 0.9758 whereas, AUC fast/fed ratio was 0.9386, which being nearly equivalent, confirmed the food effect attenuation. Therefore, the results of the study demonstrate optimal pharmacokinetics of ABA NLC and its utility in circumventing the fast fed variability.

3.
Cureus ; 16(6): e62431, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39011194

RESUMEN

Cruveilhier-Baumgarten syndrome presents a rare manifestation of portal hypertension characterized by a portosystemic shunt through a dilated paraumbilical vein, typically accompanied by classical signs such as caput medusae and a venous hum. We report a compelling case of a 41-year-old male presenting with portal hypertension, exhibiting clinical and radiological features of Cruveilhier-Baumgarten syndrome but notably lacking the characteristic venous hum. Clinical examination revealed moderate splenomegaly with prominent dilated veins and venous thrill but no caput medusae. Laboratory investigations indicated thrombocytopenia and esophageal varices on upper GI endoscopy. Imaging studies confirmed portal hypertension with findings consistent with Cruveilhier-Baumgarten syndrome, including a dilated paraumbilical vein and splenic artery aneurysms, along with the unexpected absence of a venous hum. Despite the classical radiological features, our patient did not present with hematemesis, possibly attributed to the presence of paraumbilical veins. This case highlights the diagnostic challenges and atypical presentations of Cruveilhier-Baumgarten syndrome, emphasizing the importance of comprehensive clinical evaluation and imaging modalities in its diagnosis and management. Management strategies primarily focus on addressing portal hypertension and underlying liver disease. This case underscores the need for further research to elucidate the varied clinical presentations and pathophysiology of Cruveilhier-Baumgarten syndrome variants, enhancing our understanding and management of this rare entity.

4.
Food Chem ; 459: 140244, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38991448

RESUMEN

Protein-rich fish processing by-products, often called rest raw materials (RRM), account for approximately 60% of the total fish biomass. However, a considerable amount of these RRM is utilized for low-value products such as fish meal and silage. A promising and valuable approach for maximizing the utilization of RRM involves the extraction of bioactive fish protein hydrolysate (FPH). This review assesses and compares different hydrolyzation methods to produce FPH. Furthermore, the review highlights the purification strategy, nutritional compositions, and bioactive properties of FPH. Finally, it concludes by outlining the application of FPH in food products together with various safety and regulatory issues related to the commercialization of FPH as a protein ingredient in food. This review paves the way for future applications by highlighting efficient biotechnological methods for valorizing RRM into FPH and addressing safety concerns, enabling the widespread utilization of FPH as a valuable and sustainable source of protein.

5.
JAMA Psychiatry ; 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38985482

RESUMEN

Importance: While abundant work has examined patient-level differences in antidepressant treatment outcomes, little is known about the extent of clinician-level differences. Understanding these differences may be important in the development of risk models, precision treatment strategies, and more efficient systems of care. Objective: To characterize differences between outpatient clinicians in treatment selection and outcomes for their patients diagnosed with major depressive disorder across academic medical centers, community hospitals, and affiliated clinics. Design, Setting, and Participants: This was a longitudinal cohort study using data derived from electronic health records at 2 large academic medical centers and 6 community hospitals, and their affiliated outpatient networks, in eastern Massachusetts. Participants were deidentified clinicians who billed at least 10 International Classification of Diseases, Ninth Revision (ICD-9) or Tenth Revision (ICD-10) diagnoses of major depressive disorder per year between 2008 and 2022. Data analysis occurred between September 2023 and January 2024. Main Outcomes and Measures: Heterogeneity of prescribing, defined as the number of distinct antidepressants accounting for 75% of prescriptions by a given clinician; proportion of patients who did not return for follow-up after an index prescription; and proportion of patients receiving stable, ongoing antidepressant treatment. Results: Among 11 934 clinicians treating major depressive disorder, unsupervised learning identified 10 distinct clusters on the basis of ICD codes, corresponding to outpatient psychiatry as well as oncology, obstetrics, and primary care. Between these clusters, substantial variability was identified in the proportion of selective serotonin reuptake inhibitors, selective norepinephrine reuptake inhibitors, and tricyclic antidepressants prescribed, as well as in the number of distinct antidepressants prescribed. Variability was also detected between clinician clusters in loss to follow-up and achievement of stable treatment, with the former ranging from 27% to 69% and the latter from 22% to 42%. Clinician clusters were significantly associated with treatment outcomes. Conclusions and Relevance: Groups of clinicians treating individuals diagnosed with major depressive disorder exhibit marked differences in prescribing patterns as well as longitudinal patient outcomes defined by electronic health records. Incorporating these group identifiers yielded similar prediction to more complex models incorporating individual codes, suggesting the importance of considering treatment context in efforts at risk stratification.

6.
Clin Exp Ophthalmol ; 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38937978

RESUMEN

BACKGROUND: Paediatric vitreoretinal pathology is distinct from adult cases in both presentation and surgical planning. Here we aim to report the aetiology and epidemiology in children 0-18 years requiring vitreoretinal surgery at a major tertiary paediatric hospital in Queensland, Australia. METHODS: Retrospective review of cases requiring vitreoretinal surgery between May 2015 and October 2022 was conducted. Demographics, ocular and medical history, surgical pathology, procedures performed, and epidemiology data were retrieved. Patients were grouped into three main aetiologies: traumatic, syndromic, or secondary. RESULTS: A total of 124 patients, the majority male (87, 70.2%) with a mean age of 10.3 years underwent vitreoretinal surgery. Trauma accounted for 32.3% of cases requiring surgery of which 47% were due to a penetrating eye injury. 35.5% were associated with a syndromic cause with common aetiology including coats, congenital cataract, sticklers, and retinopathy of prematurity. 32.3% developed secondary pathology and retinal detachment was the primary cause for surgery (55%). The average time from symptom onset to presentation was 30 days (SD 56.88) with patients living an average of 306.2 km (SD 558.9) away from the Queensland Children's Hospital. Older age was significantly associated with increased days to presentation in the traumatic group (p < 0.05). CONCLUSIONS: This study provides an insight into the aetiology and epidemiology of paediatric vitreoretinal presentations in Queensland, Australia.

7.
Sci Total Environ ; 946: 174167, 2024 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-38917898

RESUMEN

Globally, COVID-19 has not only caused tremendous negative health, social and economic impacts, but it has also led to environmental issues such as a massive increase in biomedical waste. The biomedical waste (BMW) was generated from centralized (hospitals, clinics, and research facilities) and extended (quarantine camps, COVID-19 test camps, and quarantined homes) healthcare facilities. Many effects, such as the possibility of infection spread, unlawful dumping/disposal, and an increase in toxic emissions by common BMW treatment facilities, are conjectured because of the rise in waste generation. However, it is also an opportunity to critically analyze the current BMW treatment scenario and implement changes to make the system more economical and environmentally sustainable. In this review, the waste disposal guidelines of the BMW management infrastructure are critically analyzed for many functional parameters to bring out possible applications and limitations of individual interventions. In addition, an investigation was made to select appropriate technology based on the environmental setting.

8.
Indian J Endocrinol Metab ; 28(2): 104-116, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38911116

RESUMEN

Obesity has erupted as an epidemic around the world. It has set itself as a fast wave among other prevailing specific clusters of non-communicable diseases. The current study reviews and presents an updated meaningful review of the vast research work performed at schools located in different cities of India. A systematic search was conducted in PubMed, Scopus, Google Scholar and PEDro. Studies representing data on obesity and overweight among children in Indian cities were included in the review. A total of 21 articles with 71,466 participants were included in the review for analysis. Obesity developed in childhood and adolescence is greatly associated with heart disease, stroke and cancer (breast and ovarian in women and prostate in men) in the late stage of life. In India, despite being a country with a faster rate of population becoming overweight and obese in urban areas, in contrast, rural areas are still struggling with malnutrition.

9.
Nucleic Acids Res ; 52(12): 6994-7011, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38828775

RESUMEN

The clinical success of PARP1/2 inhibitors (PARPi) prompts the expansion of their applicability beyond homologous recombination deficiency. Here, we demonstrate that the loss of the accessory subunits of DNA polymerase epsilon, POLE3 and POLE4, sensitizes cells to PARPi. We show that the sensitivity of POLE4 knockouts is not due to compromised response to DNA damage or homologous recombination deficiency. Instead, POLE4 loss affects replication speed leading to the accumulation of single-stranded DNA gaps behind replication forks upon PARPi treatment, due to impaired post-replicative repair. POLE4 knockouts elicit elevated replication stress signaling involving ATR and DNA-PK. We find POLE4 to act parallel to BRCA1 in inducing sensitivity to PARPi and counteracts acquired resistance associated with restoration of homologous recombination. Altogether, our findings establish POLE4 as a promising target to improve PARPi driven therapies and hamper acquired PARPi resistance.


Asunto(s)
Proteína BRCA1 , ADN Polimerasa II , Replicación del ADN , Inhibidores de Poli(ADP-Ribosa) Polimerasas , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Humanos , Proteína BRCA1/genética , Proteína BRCA1/metabolismo , ADN Polimerasa II/metabolismo , ADN Polimerasa II/genética , Replicación del ADN/efectos de los fármacos , Daño del ADN , Línea Celular Tumoral , Recombinación Homóloga/genética , Recombinación Homóloga/efectos de los fármacos , Resistencia a Antineoplásicos/genética
10.
BMC Genom Data ; 25(1): 63, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38898391

RESUMEN

OBJECTIVES: Sabkhas represent polyextreme environments characterized by elevated salinity levels, intense ultraviolet (UV) radiation exposure, and extreme temperature fluctuations. In this study, we present the complete genomes of five bacterial isolates isolated from the sabkha-shore region and investigate their genomic organization and gene annotations. A better understanding of the bacterial genomic organization and genetic adaptations of these bacteria holds promise for engineering microbes with tailored functionalities for diverse industrial and agricultural applications, including bioremediation and promotion of plant growth under salinity stress conditions. DATA DESCRIPTION: We present a comprehensive genome sequencing and annotation of five bacteria (kcgeb_sa, kcgeb_sc, kcgeb_sd, kcgeb_S4, and kcgeb_S11) obtained from the shores of the Abu Dhabi Sabkha region. Initial bacterial identification was conducted through 16 S rDNA amplification and sequencing. Employing a hybrid genome assembly technique combining Illumina short reads (NovaSeq 6000) and Oxford Nanopore long reads (MinION), we obtained complete annotated high-quality gap-free genome sequences. The genome sizes of the kcgeb_sa, kcgeb_sc, kcgeb_sd, kcgeb_S4, and kcgeb_S11 isolates were determined to be 2.4 Mb, 4.1 Mb, 2.9 Mb, 5.05 Mb, and 4.1 Mb, respectively. Our analysis conclusively assigned the bacterial isolates as Staphylococcus capitis (kcgeb_sa), Bacillus spizizenii (kcgeb_sc and kcgeb_S11), Pelagerythrobacter marensis (kcgeb_sd), and Priestia aryabhattai (kcgeb_S4).


Asunto(s)
Genoma Bacteriano , Anotación de Secuencia Molecular , Genoma Bacteriano/genética , Bacterias/genética , Bacterias/aislamiento & purificación , Bacterias/clasificación , Filogenia
11.
Invest Ophthalmol Vis Sci ; 65(5): 22, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38743414

RESUMEN

Purpose: To describe the clinical, electrophysiological and genetic spectrum of inherited retinal diseases associated with variants in the PRPH2 gene. Methods: A total of 241 patients from 168 families across 15 sites in 9 countries with pathogenic or likely pathogenic variants in PRPH2 were included. Records were reviewed for age at symptom onset, visual acuity, full-field ERG, fundus colour photography, fundus autofluorescence (FAF), and SD-OCT. Images were graded into six phenotypes. Statistical analyses were performed to determine genotype-phenotype correlations. Results: The median age at symptom onset was 40 years (range, 4-78 years). FAF phenotypes included normal (5%), butterfly pattern dystrophy, or vitelliform macular dystrophy (11%), central areolar choroidal dystrophy (28%), pseudo-Stargardt pattern dystrophy (41%), and retinitis pigmentosa (25%). Symptom onset was earlier in retinitis pigmentosa as compared with pseudo-Stargardt pattern dystrophy (34 vs 44 years; P = 0.004). The median visual acuity was 0.18 logMAR (interquartile range, 0-0.54 logMAR) and 0.18 logMAR (interquartile range 0-0.42 logMAR) in the right and left eyes, respectively. ERG showed a significantly reduced amplitude across all components (P < 0.001) and a peak time delay in the light-adapted 30-Hz flicker and single-flash b-wave (P < 0.001). Twenty-two variants were novel. The central areolar choroidal dystrophy phenotype was associated with 13 missense variants. The remaining variants showed marked phenotypic variability. Conclusions: We described six distinct FAF phenotypes associated with variants in the PRPH2 gene. One FAF phenotype may have multiple ERG phenotypes, demonstrating a discordance between structure and function. Given the vast spectrum of PRPH2 disease our findings are useful for future clinical trials.


Asunto(s)
Electrorretinografía , Periferinas , Fenotipo , Distrofias Retinianas , Agudeza Visual , Humanos , Periferinas/genética , Persona de Mediana Edad , Adulto , Masculino , Femenino , Adolescente , Distrofias Retinianas/genética , Distrofias Retinianas/fisiopatología , Distrofias Retinianas/diagnóstico , Anciano , Agudeza Visual/fisiología , Niño , Adulto Joven , Preescolar , Tomografía de Coherencia Óptica , Mutación , Angiografía con Fluoresceína , Estudios de Asociación Genética , Estudios Retrospectivos , Análisis Mutacional de ADN , ADN/genética , Linaje
13.
Neurosci Lett ; 833: 137826, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38768940

RESUMEN

Synucleins are pivotal in neurodegenerative conditions. Beta-synuclein (ß-synuclein) is part of the synuclein protein family alongside alpha-synuclein (α-synuclein) and gamma-synuclein (γ-synuclein). These proteins, found mainly in brain tissue and cancers, are soluble and unstructured. ß-synuclein shares significant similarity with α-synuclein, especially in their N-terminus, with a 90% match. However, their aggregation tendencies differ significantly. While α-synuclein aggregation is believed to be counteracted by ß-synuclein, which occurs in conditions like Parkinson's disease, ß-synuclein may counteract α-synuclein's toxic effects on the nervous system, offering potential treatment for neurodegenerative diseases. Under normal circumstances, ß-synuclein may guard against disease by interacting with α-synuclein. Yet, in pathological environments with heightened levels or toxic substances, it might contribute to disease. Our research aims to explore potential harmful mutations in the ß-synuclein using computational tools to predict their destabilizing impact on protein structure. Consensus analysis revealed rs1207608813 (A63P), rs1340051870 (S72F), and rs1581178262 (G36C) as deleterious. These findings highlight the intricate relationship between nsSNPs and protein function, shedding light on their potential implications in disease pathways. Understanding the structural consequences of nsSNPs is crucial for elucidating their role in pathogenesis and developing targeted therapeutic interventions. Our results offer a robust computational framework for identifying neurodegenerative disorder-related mutations from SNP datasets, potentially reducing the costs associated with experimental characterization.


Asunto(s)
Polimorfismo de Nucleótido Simple , Sinucleína beta , Sinucleína beta/genética , Sinucleína beta/metabolismo , Sinucleína beta/química , Humanos , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , alfa-Sinucleína/química , Predisposición Genética a la Enfermedad , Mutación , Conformación Proteica
14.
Sci Rep ; 14(1): 10118, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38698069

RESUMEN

Under grid voltage sags, over current protection and exploiting the maximum capacity of the inverter are the two main goals of grid-connected PV inverters. To facilitate low-voltage ride-through (LVRT), it is imperative to ensure that inverter currents are sinusoidal and remain within permissible limits throughout the inverter operation. An improved LVRT control strategy for a two-stage three-phase grid-connected PV system is presented here to address these challenges. To provide over current limitation as well as to ensure maximum exploitation of the inverter capacity, a control strategy is proposed, and performance the strategy is evaluated based on the three generation scenarios on a 2-kW grid connected PV system. An active power curtailment (APC) loop is activated only in high power generation scenario to limit the current's amplitude below the inverter's rated current. The superior performance of the proposed strategy is established by comparison with two recent LVRT control strategies. The proposed method not only injects necessary active and reactive power but also minimizes overcurrent with increased exploitation of the inverter's capacity under unbalanced grid voltage sag.

15.
Pain Manag Nurs ; 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38719655

RESUMEN

BACKGROUND: Breast cancer is the most commonly diagnosed cancer among women globally, with significant impacts on physical, emotional, and functional well-being. Traditional rehabilitation methods may not fully address the multifaceted challenges faced by breast cancer survivors (BCSs), prompting exploration into innovative approaches such as Virtual Reality (VR) technology. OBJECTIVE: The present review aims to assess the effectiveness of VR in alleviating pain, improving Range of Motion (ROM), enhancing muscle strength, and augmenting the overall quality of life in patients undergoing breast cancer rehabilitation. METHODS: A comprehensive review of existing literature was conducted, focusing on studies investigating the use of VR in breast cancer rehabilitation. PubMed, Scopus, PEDro and Google scholar were searched for articles addressing VR interventions targeting pain management, ROM improvement, muscle strength enhancement, and quality of life enhancement in breast cancer patients. RESULTS: Findings yielded total 12 articles matching the selection criteria. VR technology has shown promising results in addressing the multifaceted needs of breast cancer patients. VR also serves as a distraction tool, positively impacting psychological well-being and mitigating negative psychological symptoms associated with the disease. CONCLUSION: VR represents a non-pharmacological approach to pain management and rehabilitation in breast cancer patients. Its ability to engage emotional, cognitive, and attention processes contributes to its effectiveness in enhancing overall quality of life. Further research is warranted to elucidate the long-term benefits and optimal utilization of VR technology in breast cancer rehabilitation programs.

16.
ACS Cent Sci ; 10(5): 1054-1064, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38799656

RESUMEN

Current approaches to evaluate molecular complexity use algorithmic complexity, rooted in computer science, and thus are not experimentally measurable. Directly evaluating molecular complexity could be used to study directed vs undirected processes in the creation of molecules, with potential applications in drug discovery, the origin of life, and artificial life. Assembly theory has been developed to quantify the complexity of a molecule by finding the shortest path to construct the molecule from building blocks, revealing its molecular assembly index (MA). In this study, we present an approach to rapidly infer the MA of molecules from spectroscopic measurements. We demonstrate that the MA can be experimentally measured by using three independent techniques: nuclear magnetic resonance (NMR), tandem mass spectrometry (MS/MS), and infrared spectroscopy (IR). By identifying and analyzing the number of absorbances in IR spectra, carbon resonances in NMR, or molecular fragments in tandem MS, the MA of an unknown molecule can be reliably estimated. This represents the first experimentally quantifiable approach to determining molecular assembly. This paves the way to use experimental techniques to explore the evolution of complex molecules as well as a unique marker of where an evolutionary process has been operating.

17.
Ecancermedicalscience ; 18: 1700, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38774570

RESUMEN

Background: Craniospinal irradiation (CSI) poses a challenging planning process because of the complex target volume. Traditional 3D conformal CSI does not spare any critical organs, resulting in toxicity in patients. Here the dosimetric advantages of volumetric-modulated arc therapy (VMAT) using partial arc and avoidance sectors are compared with each other in planning in adult patients undergoing CSI to develop a clinically feasible technique that is both effective and efficient. Patient and methods: Eight adult patients treated with CSI were retrospectively identified. In total 16 plans were made. We generated two plans for each patient: 1. VMAT plan using partial arc, namely VMAT_pa. 2. VMAT plan using avoidance sectors, namely VMAT_as. The dose prescribed was 36 Gy in 20 fractions. The dose-volume histogram for planning target volume (PTV) and organs at risk (OAR) (lens, eye, heart, thyroid, lungs, liver, gonads and kidneys) were analysed and compared. Dose parameters of mean dose, V95%, and V107% for the PTV were evaluated. Results: The median length of PTV is 65.58 cm (45.8-79.5). The volume of PTV receiving 95% of the dose (V95%) in both the plans are 97.51% (VMAT_as) and 97.99% (VMAT_pa) (p = 0.121) while V107% are 0.733 and 0.742 for VMAT_as and VMAT_pa, respectively (p = 0.969). The doses of OARs such as lens, eye, liver and gonads were comparable. The mean heart dose was 10.4 and 9.0 Gy in VMAT_as and VMAT_pa plans, respectively (p = 0.005). Significant lower doses to the thyroid, kidneys and lungs were seen in VMAT plans using avoidance sectors. Conclusion: This study provides a practically useful VMAT planning method for the treatment of CSI and illustrates the ability of VMAT using avoidance sectors to generate highly conformal and homogeneous treatment plans for CSI, while limiting the dose to the relevant OARs.

18.
PLoS Genet ; 20(4): e1011232, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38669270

RESUMEN

Animals often grow and develop in unpredictable environments where factors like food availability, temperature, and oxygen levels can fluctuate dramatically. To ensure proper sexual maturation into adulthood, juvenile animals need to adapt their growth and developmental rates to these fluctuating environmental conditions. Failure to do so can result in impaired maturation and incorrect body size. Here we describe a mechanism by which Drosophila larvae adapt their development in low oxygen (hypoxia). During normal development, larvae grow and increase in mass until they reach critical weight (CW), after which point a neuroendocrine circuit triggers the production of the steroid hormone ecdysone from the prothoracic gland (PG), which promotes maturation to the pupal stage. However, when raised in hypoxia (5% oxygen), larvae slow their growth and delay their maturation to the pupal stage. We find that, although hypoxia delays the attainment of CW, the maturation delay occurs mainly because of hypoxia acting late in development to suppress ecdysone production. This suppression operates through a distinct mechanism from nutrient deprivation, occurs independently of HIF-1 alpha and does not involve dilp8 or modulation of Ptth, the main neuropeptide that initiates ecdysone production in the PG. Instead, we find that hypoxia lowers the expression of the EGF ligand, spitz, and that the delay in maturation occurs due to reduced EGFR/ERK signaling in the PG. Our study sheds light on how animals can adjust their development rate in response to changing oxygen levels in their environment. Given that hypoxia is a feature of both normal physiology and many diseases, our findings have important implications for understanding how low oxygen levels may impact animal development in both normal and pathological situations.


Asunto(s)
Proteínas de Drosophila , Drosophila melanogaster , Ecdisona , Factor de Crecimiento Epidérmico , Larva , Transducción de Señal , Animales , Ecdisona/metabolismo , Larva/crecimiento & desarrollo , Larva/genética , Larva/metabolismo , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/genética , Factor de Crecimiento Epidérmico/metabolismo , Factor de Crecimiento Epidérmico/genética , Drosophila melanogaster/crecimiento & desarrollo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Hipoxia/metabolismo , Regulación del Desarrollo de la Expresión Génica , Receptores ErbB/metabolismo , Receptores ErbB/genética , Oxígeno/metabolismo , Pupa/crecimiento & desarrollo , Pupa/metabolismo , Pupa/genética
19.
J Colloid Interface Sci ; 665: 988-998, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38574587

RESUMEN

In applications utilizing Covalent Organic Frameworks (COFs) for adsorption, the interplay between crystallinity (vis-à-vis surface area) and active sites still remains ambiguous. To address this, the present study introduces three isoreticular COFs-COP-N18 (covalent organic polymer with short-range order), COF-N18 (COF having long-range order), and COF-N27 (semicrystalline COF with pyridyl heteroatoms)-to explore this duality. Through systematic variations in structural order, pore volume, and pore-wall nitrogen content, we aim to establish a structure-activity relationship (SAR) for these COFs via adsorption and catalysis, using CO2 and I2 as probes. Our investigation highlights the positive influence of crystallinity, surface area, and pore volume in adsorption as well as catalysis. However, the presence of heteroatoms manifests complex behavior in CO2 adsorption and CO2 cycloaddition reactions with epoxides. COF-N18 and COF-N27 showed comparable CO2 uptake capacities at different temperatures (273, 293, and 313 K) and ∼1 bar pressure. Additionally, CO2 cycloaddition reactions were performed with substrates possessing different polarities (epichlorohydrin, 1,2-epoxydodecane) to elucidate the role of COF surface polarity. Further investigation into iodine adsorption was performed to understand the impact of COF structural features on the modes of adsorption and adsorption kinetics. Improvements in COF-crystallinity results in faster average iodine uptake rate at 80% (K80% = 1.79 g/h) by COF-N18. Whereas, heteroatom doping slows down iodine adsorption kinetics (0.35 g/h) by prolonging the adsorption process up to 72 h. Overall, this study advances our understanding of COFs as adsorbents and catalysts, providing key insights into their SAR while emphasizing structural fine-tuning as a key factor for impactful environmental applications.

20.
PLoS One ; 19(4): e0300653, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38557860

RESUMEN

Photonic radar, a cornerstone in the innovative applications of microwave photonics, emerges as a pivotal technology for future Intelligent Transportation Systems (ITS). Offering enhanced accuracy and reliability, it stands at the forefront of target detection and recognition across varying weather conditions. Recent advancements have concentrated on augmenting radar performance through high-speed, wide-band signal processing-a direct benefit of modern photonics' attributes such as EMI immunity, minimal transmission loss, and wide bandwidth. Our work introduces a cutting-edge photonic radar system that employs Frequency Modulated Continuous Wave (FMCW) signals, synergized with Mode Division and Wavelength Division Multiplexing (MDM-WDM). This fusion not only enhances target detection and recognition capabilities across diverse weather scenarios, including various intensities of fog and solar scintillations, but also demonstrates substantial resilience against solar noise. Furthermore, we have integrated machine learning techniques, including Decision Tree, Extremely Randomized Trees (ERT), and Random Forest classifiers, to substantially enhance target recognition accuracy. The results are telling: an accuracy of 91.51%, high sensitivity (91.47%), specificity (97.17%), and an F1 Score of 91.46%. These metrics underscore the efficacy of our approach in refining ITS radar systems, illustrating how advancements in microwave photonics can revolutionize traditional methodologies and systems.


Asunto(s)
Radar , Tiempo (Meteorología) , Reproducibilidad de los Resultados , Benchmarking , Aprendizaje Automático
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...