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1.
Nature ; 612(7940): 488-494, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36450990

RESUMO

Insect societies are tightly integrated, complex biological systems in which group-level properties arise from the interactions between individuals1-4. However, these interactions have not been studied systematically and therefore remain incompletely known. Here, using a reverse engineering approach, we reveal that unlike solitary insects, ant pupae extrude a secretion derived from the moulting fluid that is rich in nutrients, hormones and neuroactive substances. This secretion elicits parental care behaviour and is rapidly removed and consumed by the adults. This behaviour is crucial for pupal survival; if the secretion is not removed, pupae develop fungal infections and die. Analogous to mammalian milk, the secretion is also an important source of early larval nutrition, and young larvae exhibit stunted growth and decreased survival without access to the fluid. We show that this derived social function of the moulting fluid generalizes across the ants. This secretion thus forms the basis of a central and hitherto overlooked interaction network in ant societies, and constitutes a rare example of how a conserved developmental process can be co-opted to provide the mechanistic basis of social interactions. These results implicate moulting fluids in having a major role in the evolution of ant eusociality.


Assuntos
Formigas , Líquidos Corporais , Muda , Pupa , Comportamento Social , Animais , Formigas/crescimento & desenvolvimento , Formigas/fisiologia , Larva/fisiologia , Muda/fisiologia , Pupa/fisiologia , Líquidos Corporais/fisiologia
2.
Proc Natl Acad Sci U S A ; 121(17): e2314450121, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38621133

RESUMO

Proteinaceous brain inclusions, neuroinflammation, and vascular dysfunction are common pathologies in Alzheimer's disease (AD). Vascular deficits include a compromised blood-brain barrier, which can lead to extravasation of blood proteins like fibrinogen into the brain. Fibrinogen's interaction with the amyloid-beta (Aß) peptide is known to worsen thrombotic and cerebrovascular pathways in AD. Lecanemab, an FDA-approved antibody therapy for AD, clears Aß plaque from the brain and slows cognitive decline. Here, we show that lecanemab blocks fibrinogen's binding to Aß protofibrils, preventing Aß/fibrinogen-mediated delayed fibrinolysis and clot abnormalities in vitro and in human plasma. Additionally, we show that lecanemab dissociates the Aß/fibrinogen complex and prevents fibrinogen from exacerbating Aß-induced synaptotoxicity in mouse organotypic hippocampal cultures. These findings reveal a possible protective mechanism by which lecanemab may slow disease progression in AD.


Assuntos
Doença de Alzheimer , Anticorpos Monoclonais Humanizados , Trombose , Camundongos , Humanos , Animais , Fibrinogênio/metabolismo , Sistemas Microfisiológicos , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/toxicidade , Peptídeos beta-Amiloides/metabolismo
3.
Ann Pharmacother ; 58(1): 44-53, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37026168

RESUMO

BACKGROUND: Chemotherapy, the only treatment option for metastatic triple-negative breast cancer (mTNBC), showed decreased survival rates. Trophoblast cell surface antigen-2 (Trop-2) could be a possible target for antibody-drug conjugates (ADCs). OBJECTIVE: Sacituzumab govitecan (SG), an anti-Trop-2 ADC for pretreating relapsed/refractory mTNBC patients, was studied to know the efficacy and safety profile of the drug in mTNBC. METHODS: The present review searched MEDLINE (via PubMed), WHO Clinical Trial Registry, Clinical Trials.gov, and Cochrane Central Register of Controlled Trials until December 25, 2022. The studies searched comprised randomized trials and observational studies (retrospective [case-control, cross-sectional] and prospective [cohort designs]). Efficacy assessment was performed in terms of complete response (CR), partial response (PR), objective response rate (ORR), stable disease (SD), progressive disease (PD), and clinical benefit rate (CBR), and safety in terms of adverse events. RESULTS: The overall random-effects pooled prevalence of CR was 4.9 (95% CI: 3.2-7.1), PR was 35.6 (95% CI: 31.5-39.9), ORR was 6.8 (95% CI: 5.9-7.8), SD was 8.0 (95% CI: 6.7-9.4), PD was 5.1 (95% CI: 4.1-6.3), and CBR was 13.4 (95% CI: 11.8-15.1). Adverse events associated with the drug were neutropenia, fatigue, anemia, nausea, and others. CONCLUSION AND RELEVANCE: This is the first meta-analysis conducted in relapsed/refractory mTNBC patients and found that SG is efficacious but associated with some adverse effects that are related to exposure to the drug. The application of these results will allow clinicians to use SG in the management of patients with mTNBC.


Assuntos
Imunoconjugados , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Estudos Transversais , Estudos Prospectivos , Estudos Retrospectivos , Camptotecina/efeitos adversos , Imunoconjugados/efeitos adversos
4.
J Cutan Pathol ; 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38695362

RESUMO

Mammary-type tissue in the vulva was first described in 1872 but has been rarely reported in the literature. This tissue was previously considered as ectopic breast tissue that occurs as a result of incomplete regression of the milk line. Similar to native breast tissue, ectopic mammary tissue is hormone-sensitive and can develop benign changes, such as fibroadenoma, as well as malignant changes. A more recent theory suggests that these benign and malignant mammary-type entities arise from mammary-like anogenital glands, which constitute normal vulvar components. We report a case of a 41-year-old woman who presented with a chronic asymptomatic cyst on the left vulva that eventually became uncomfortable, especially on standing. The cyst was located on the labium minus, measuring 1.0 × 0.5 cm, with no identified erythema or other skin abnormalities. Excision of the lesion and subsequent microscopic examination showed a circumscribed mass with a nodular overgrowth of epithelial and stromal components, resembling a mammary fibroadenoma with pseudoangiomatous stromal hyperplasia. We bring to attention this rare diagnosis and the importance of considering it in the presence of a vulvar lesion. The malignant and recurrence potential of mammary-type tissue necessitates excision with clear margins and close monitoring of these patients.

5.
J Paediatr Child Health ; 60(4-5): 100-106, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38597355

RESUMO

AIM: Bronchiolitis is the commonest reason for hospitalisation amongst infants and is often a target for low-value care (LVC) reduction. We aimed to assess the impact of a multifaceted intervention (clinician education, parent engagement, audit-feedback) on rates of chest x-rays (CXR) in bronchiolitis. METHODS: Longitudinal study of CXRs ordered in infants (1-12 months) diagnosed with bronchiolitis in the Emergency Department (ED) of an Australian paediatric hospital between May 2016 and February 2023. We used logistic regression to measure the impact of the intervention on unwarranted CXR orders, controlling for other potential impacting variables such as time, patient characteristics (age/sex), clinical variables (fever, hypoxia, tachypnoea), seasonal factors (month, day of the week, business hours) and time passed since intervention. RESULTS: Ten thousand one hundred and nine infants were diagnosed with bronchiolitis in the ED over the study period, with 939 (9.3%) receiving a CXR, of which 69% (n = 651) were considered unwarranted. Rates of unwarranted CXRs reduced from 7.9% to 5.4% post-intervention (P < 0.0001). Logistic regression showed the intervention had no significant effect (OR 0.89, 95% CI 0.65-1.23) once other variables and underlying time-based trends were accounted for. CONCLUSIONS: Although pre-post rates appeared significantly improved, a robust analysis demonstrated that our multi-faceted intervention was not effective in reducing CXRs in bronchiolitis. The decision to order CXR was associated with clinical features that overlap with pneumonia suggesting ongoing misconceptions regarding the role of CXR for this indication. Our study highlights the value of large electronic medical record datasets and robust methodology to avoid falsely attributing underlying trends to the LVC intervention.


Assuntos
Bronquiolite , Radiografia Torácica , Humanos , Bronquiolite/diagnóstico por imagem , Lactente , Masculino , Feminino , Radiografia Torácica/métodos , Estudos Longitudinais , Austrália , Serviço Hospitalar de Emergência , Procedimentos Desnecessários , Modelos Logísticos
6.
Proc Natl Acad Sci U S A ; 118(42)2021 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-34654749

RESUMO

The term "de-etiolation" refers to the light-dependent differentiation of etioplasts to chloroplasts in angiosperms. The underlying process involves reorganization of prolamellar bodies (PLBs) and prothylakoids into thylakoids, with concurrent changes in protein, lipid, and pigment composition, which together lead to the assembly of active photosynthetic complexes. Despite the highly conserved structure of PLBs among land plants, the processes that mediate PLB maintenance and their disassembly during de-etiolation are poorly understood. Among chloroplast thylakoid membrane-localized proteins, to date, only Curvature thylakoid 1 (CURT1) proteins were shown to exhibit intrinsic membrane-bending capacity. Here, we show that CURT1 proteins, which play a critical role in grana margin architecture and thylakoid plasticity, also participate in de-etiolation and modulate PLB geometry and density. Lack of CURT1 proteins severely perturbs PLB organization and vesicle fusion, leading to reduced accumulation of the light-dependent enzyme protochlorophyllide oxidoreductase (LPOR) and a delay in the onset of photosynthesis. In contrast, overexpression of CURT1A induces excessive bending of PLB membranes, which upon illumination show retarded disassembly and concomitant overaccumulation of LPOR, though without affecting greening or the establishment of photosynthesis. We conclude that CURT1 proteins contribute to the maintenance of the paracrystalline PLB morphology and are necessary for efficient and organized thylakoid membrane maturation during de-etiolation.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Tilacoides/metabolismo , Arabidopsis/fisiologia , Clorofila/metabolismo , Microscopia Eletrônica/métodos , Fotossíntese
7.
Sensors (Basel) ; 24(4)2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38400487

RESUMO

Organizations managing high-performance computing systems face a multitude of challenges, including overarching concerns such as overall energy consumption, microprocessor clock frequency limitations, and the escalating costs associated with chip production. Evidently, processor speeds have plateaued over the last decade, persisting within the range of 2 GHz to 5 GHz. Scholars assert that brain-inspired computing holds substantial promise for mitigating these challenges. The spiking neural network (SNN) particularly stands out for its commendable power efficiency when juxtaposed with conventional design paradigms. Nevertheless, our scrutiny has brought to light several pivotal challenges impeding the seamless implementation of large-scale neural networks (NNs) on silicon. These challenges encompass the absence of automated tools, the need for multifaceted domain expertise, and the inadequacy of existing algorithms to efficiently partition and place extensive SNN computations onto hardware infrastructure. In this paper, we posit the development of an automated tool flow capable of transmuting any NN into an SNN. This undertaking involves the creation of a novel graph-partitioning algorithm designed to strategically place SNNs on a network-on-chip (NoC), thereby paving the way for future energy-efficient and high-performance computing paradigms. The presented methodology showcases its effectiveness by successfully transforming ANN architectures into SNNs with a marginal average error penalty of merely 2.65%. The proposed graph-partitioning algorithm enables a 14.22% decrease in inter-synaptic communication and an 87.58% reduction in intra-synaptic communication, on average, underscoring the effectiveness of the proposed algorithm in optimizing NN communication pathways. Compared to a baseline graph-partitioning algorithm, the proposed approach exhibits an average decrease of 79.74% in latency and a 14.67% reduction in energy consumption. Using existing NoC tools, the energy-latency product of SNN architectures is, on average, 82.71% lower than that of the baseline architectures.

8.
Semin Cancer Biol ; 87: 127-136, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36265806

RESUMO

Indiscriminate usage and mismanagement of chemicals in the agricultural and industrial sectors have contaminated different environmental compartments. Exposure to these persistent and hazardous pollutants like heavy metals, endocrine disruptors, aromatic hydrocarbons, and pesticides can result in various health adversities, including cancer. Chemical carcinogens follow a similar pattern of carcinogenesis, like oxidative stress, chromosomal aberration, DNA double-strand break, mismatch repair, and misregulation of oncogenic and/or tumor suppressors. Out of several cancer-associated endpoints, cellular metabolic homeostasis is the commonest to be deregulated upon chemical exposure. Chemical carcinogens hamper glycolytic reprogramming to fuel the malignant transformation of the cells and/or promote cancer progression. Several regulators like Akt, ERK, Ras, c-Myc, HIF-1α, and p53 regulate glycolysis in chemical-induced carcinogenesis. However, the deregulation of the anabolic biochemistry of glucose during chemical-induced carcinogenesis remains to be uncovered. This review comprehensively covers the environmental chemical-induced glycolytic shift during carcinogenesis and its mechanism. The focus is also to fill the major gaps associated with understanding the fairy tale between environmental carcinogens and metabolic reprogramming. Although evidence from studies regarding glycolytic reprogramming in chemical carcinogenesis provides valuable insights into cancer therapy, exposure to a mixture of toxicants and their mechanism of inducing carcinogenesis still needs to be studied.


Assuntos
Glicólise , Neoplasias , Humanos , Neoplasias/induzido quimicamente , Carcinogênese , Transformação Celular Neoplásica , Carcinógenos/toxicidade
9.
J Mol Recognit ; 36(6): e3010, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36880368

RESUMO

The binding affinity of a drug with carrier proteins plays a major role in the distribution and administration of the drug within the body. Tizanidine (TND) is a muscle relaxant having antispasmodic and antispastic effects. Herein, we have studied the effect of tizanidine on serum albumins by spectroscopic techniques, such as absorption spectroscopic analysis, steady, state fluorescence, synchronous fluorescence, circular dichroism, and molecular docking. The binding constant and number of binding sites of TND with serum proteins were determined by means of fluorescence data. The thermodynamic parameters, like Gibbs' free energy (ΔG), enthalpy change (ΔH), and entropy change (ΔS), revealed that the complex formation is spontaneous, exothermic, and entropy driven. Further, synchronous spectroscopy revealed the involvement of Trp (amino acid) responsible for quenching of intensity in fluorescence in serum albumins in presence of TND. Circular dichroism results suggest that more folded secondary structure of proteins. In BSA the presence of 20 µM concentration of TND was able to gain most of its helical content. Similarly, in HSA the presence of 40 µM concentration of TND has been able to gain more helical content. Molecular docking and molecular dynamic simulation further confirm the binding of TND with serum albumins, thus validating our experimental results.


Assuntos
Músculos , Albumina Sérica , Simulação de Acoplamento Molecular , Preparações Farmacêuticas/metabolismo , Sítios de Ligação , Dicroísmo Circular , Termodinâmica , Músculos/metabolismo , Espectrometria de Fluorescência , Ligação Proteica , Soroalbumina Bovina/química
10.
Plant Physiol ; 189(1): 49-65, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35139220

RESUMO

The endoplasmic reticulum (ER)-located ATP/ADP-antiporter (ER-ANT1) occurs specifically in vascular plants. Structurally different transporters mediate energy provision to the ER, but the cellular function of ER-ANT1 is still unknown. Arabidopsis (Arabidopsis thaliana) mutants lacking ER-ANT1 (er-ant1 plants) exhibit a photorespiratory phenotype accompanied by high glycine levels and stunted growth, pointing to an inhibition of glycine decarboxylase (GDC). To reveal whether it is possible to suppress this marked phenotype, we exploited the power of a forward genetic screen. Absence of a so far uncharacterized member of the HaloAcid Dehalogenase (HAD)-like hydrolase family strongly suppressed the dwarf phenotype of er-ant1 plants. Localization studies suggested that the corresponding protein locates to chloroplasts, and activity assays showed that the enzyme dephosphorylates, with high substrate affinity, the B6 vitamer pyridoxal 5'-phosphate (PLP). Additional physiological experiments identified imbalances in vitamin B6 homeostasis in er-ant1 mutants. Our data suggest that impaired chloroplast metabolism, but not decreased GDC activity, causes the er-ant1 mutant dwarf phenotype. We present a hypothesis, setting transport of PLP by ER-ANT1 and chloroplastic PLP dephosphorylation in the cellular context. With the identification of this HAD-type PLP phosphatase, we also provide insight into B6 vitamer homeostasis.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Trifosfato de Adenosina/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Retículo Endoplasmático/metabolismo , Fosfatos/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Fosfato de Piridoxal/metabolismo
11.
Langmuir ; 39(33): 11694-11707, 2023 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-37552772

RESUMO

Gangliosides, forming a class of lipids complemented by sugar chains, influence the lateral distribution of membrane proteins or membrane-binding proteins, act as receptors for viruses and bacterial toxins, and mediate several types of cellular signaling. Gangliosides incorporated into supported lipid bilayers (SLBs) have been widely applied as a model system to examine these biological processes. In this work, we explored how ganglioside composition affects the kinetics of SLB formation using the vesicle rupturing method on a solid surface. We imaged the attachment of vesicles and the subsequent SLB formation using the time-lapse total internal reflection fluorescence microscopy technique. In the early phase, the ganglioside type and concentration influence the adsorption kinetics of vesicles and their residence/lifetime on the surface before rupturing. Our data confirm that a simultaneous rupturing of neighboring surface-adsorbed vesicles forms microscopic lipid patches on the surface and it is triggered by a critical coverage of the vesicles independent of their composition. In the SLB growth phase, lipid patches merge, forming a continuous SLB. The propagation of patch edges catalyzes the process and depends on the ganglioside type. Our pH-dependent experiments confirm that the polar/charged head groups of the gangliosides have a critical role in these steps and phases of SLB formation kinetics.


Assuntos
Toxinas Bacterianas , Bicamadas Lipídicas , Bicamadas Lipídicas/química , Cinética , Gangliosídeos/química , Microscopia de Fluorescência
12.
Mol Biol Rep ; 50(3): 2823-2834, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36595119

RESUMO

The growing use of ionizing radiation (IR)-based diagnostic and treatment methods has been linked to increasing chronic diseases among patients and healthcare professionals. However, multiple factors such as IR dose, dose-rate, and duration of exposure influence the IR-induced chronic effects. The predicted links between low-dose ionizing radiation (LDIR) and health risks are controversial due to the non-availability of direct human studies. The studies pertaining to LDIR effects have importance in public health as exposure to background LDIR is routine. It has been anticipated that data from epidemiological and clinical reports and results of preclinical studies can resolve this controversy and help to clarify the notion of LDIR-associated health risks. Accumulating scientific literature shows reduced cancer risk, cancer-related deaths, curtailed neuro-impairments, improved neural functions, and reduced diabetes-related complications after LDIR exposure. In addition, it was found to alter evolutionarily conserved stress response pathways. However, the picture of molecular signaling pathways in LDIR responses is unclear. Besides, there is limited/no information on biomarkers of epidemiological LDIR exposure. Therefore, the present review discusses epidemiological, clinical, and preclinical studies on LDIR-induced positive effects in three chronic diseases (cancer, dementia, and diabetes) and their associated molecular mechanisms. The knowledge of LDIR response mechanisms may help to devise LDIR-based therapeutic modalities to stop disease progression. Modulation of these pathways may be helpful in developing radiation resistance among humans. However, more clinical evidence with additional biochemical, cellular, and molecular data and exploring the side effects of LDIR are the major areas of future research.


Assuntos
Demência , Diabetes Mellitus , Neoplasias , Humanos , Relação Dose-Resposta à Radiação , Radiação Ionizante , Neoplasias/epidemiologia , Neoplasias/radioterapia , Demência/epidemiologia
13.
BMC Geriatr ; 23(1): 253, 2023 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-37106318

RESUMO

BACKGROUND: Older people subject to homelessness face many challenges including poor health status, geriatric syndromes, and depression, coupled with barriers in accessing health and aged care services. Many are in need of formal aged care at a younger age than the general population, yet, in Australia, specialised aged-care services to support this vulnerable cohort are limited. METHODS: This study was an evaluation of a new purpose-built aged care home for people with high care needs and who are homeless or at risk of homelessness. Over the first 12 months post-admission, the study examined: (1) changes in residents' physical, mental, psychological and social health, and (2) the costs incurred by the study cohort, including any cost benefit derived. RESULTS: Thirty-five residents enrolled in the study between March 2020 - April 2021. At admission, almost half of residents were within the range for dementia, the majority were frail, at high risk for falls, and had scores indicative of depression. Over time, linear mixed-effect models showed significant improvement in personal wellbeing scores, with clinically significant improvements in overall health related quality of life. Levels of physical functional independence, frailty, and global cognition were stable, but cognitive functional ability declined over time. Comparison of 12 month pre- and post- admission cost utility data for a smaller cohort (n = 13) for whom complete data were available, suggested an average per resident saving of approximately AU$32,000, while the QALY indicators remained stable post-admission. CONCLUSION: While this was a small study with no control group, these preliminary positive outcomes add to the growing body of evidence that supports the need for dedicated services to support older people subject to homelessness.


Assuntos
Instituição de Longa Permanência para Idosos , Pessoas Mal Alojadas , Idoso , Humanos , Austrália/epidemiologia , Análise Custo-Benefício , Qualidade de Vida
14.
Regul Toxicol Pharmacol ; 145: 105502, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38832926

RESUMO

Many government agencies and expert groups have estimated a dose-rate of perfluorooctanoate (PFOA) that would protect human health. Most of these evaluations are based on the same studies (whether of humans, laboratory animals, or both), and all note various uncertainties in our existing knowledge. Nonetheless, the values of these various, estimated, safe-doses vary widely, with some being more than 100,000 fold different. This sort of discrepancy invites scrutiny and explanation. Otherwise what is the lay public to make of this disparity? The Steering Committee of the Alliance for Risk Assessment (2022) called for scientists interested in attempting to understand and narrow these disparities. An advisory committee of nine scientists from four countries was selected from nominations received, and a subsequent invitation to scientists internationally led to the formation of three technical teams (for a total of 24 scientists from 8 countries). The teams reviewed relevant information and independently developed ranges for estimated PFOA safe doses. All three teams determined that the available epidemiologic information could not form a reliable basis for a PFOA safe dose-assessment in the absence of mechanistic data that are relevant for humans at serum concentrations seen in the general population. Based instead on dose-response data from five studies of PFOA-exposed laboratory animals, we estimated that PFOA dose-rates 10-70 ng/kg-day are protective of human health.


Assuntos
Caprilatos , Relação Dose-Resposta a Droga , Fluorocarbonos , Cooperação Internacional , Caprilatos/toxicidade , Fluorocarbonos/toxicidade , Humanos , Animais , Medição de Risco , Poluentes Ambientais/toxicidade , Exposição Ambiental/efeitos adversos
15.
Am J Respir Cell Mol Biol ; 66(3): 302-311, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34851798

RESUMO

The 17q21 asthma susceptibility locus includes asthma risk alleles associated with decreased sphingolipid synthesis, likely resulting from increased expression of ORMDL3. ORMDL3 inhibits serine-palmitoyl transferase (SPT), the rate-limiting enzyme of de novo sphingolipid synthesis. There is evidence that decreased sphingolipid synthesis is critical to asthma pathogenesis. Children with asthma and 17q21 asthma risk alleles display decreased sphingolipid synthesis in blood cells. Reduced SPT activity results in airway hyperreactivity, a hallmark feature of asthma. 17q21 asthma risk alleles are also linked to childhood infections with human rhinovirus (RV). This study evaluates the interaction of RV with the de novo sphingolipid synthesis pathway, and the alterative effects of concurrent SPT inhibition in SPT-deficient mice and human airway epithelial cells. In mice, RV infection shifted lung sphingolipid synthesis gene expression to a pattern that resembles genetic SPT deficiency, including decreased expression of Sptssa, a small SPT subunit. This pattern was pronounced in lung epithelial cellular adhesion molecule (EpCAM+) cells and reproduced in human bronchial epithelial cells. RV did not affect Sptssa expression in lung CD45+ immune cells. RV increased sphingolipids unique to the de novo synthesis pathway in mouse lung and human airway epithelial cells. Interestingly, these de novo sphingolipid species were reduced in the blood of RV-infected wild-type mice. RV exacerbated SPT deficiency-associated airway hyperreactivity. Airway inflammation was similar in RV-infected wild-type and SPT-deficient mice. This study reveals the effects of RV infection on the de novo sphingolipid synthesis pathway, elucidating a potential mechanistic link between 17q21 asthma risk alleles and rhinoviral infection.


Assuntos
Proteínas de Membrana , Rhinovirus , Animais , Criança , Humanos , Pulmão/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Serina C-Palmitoiltransferase/genética , Serina C-Palmitoiltransferase/metabolismo , Esfingolipídeos/metabolismo
16.
Support Care Cancer ; 30(6): 5075-5083, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35217910

RESUMO

PURPOSE: Metabolic syndrome (MetSyn) is an important late effect of childhood cancer. The combination of rising obesity and high prevalence of under-nutrition at diagnosis makes this a unique population to study in LMIC (lower middle-income countries). METHODS: Children ≤ 18 years of age at cancer diagnosis, in a single center in a LMIC, who were disease free and had completed treatment at least 2 years prior to study were included. MetSyn was defined using International Federation for Diabetes criteria for Asian Indians. Logistic regression analyses were carried out to evaluate the influence of various risk factors, including delta BMI (increase in body mass index from diagnosis to evaluation), on MetSyn. RESULTS: A high prevalence of MetSyn (12.2%), central obesity (33%), and dyslipidemia (61.8%) were found in a cohort of 500 Asian Indian childhood cancer survivors (CCS) at a median follow-up age of 17 years. Multivariable analysis revealed older age at diagnosis ≥ 10 years, OR 2.9 (1.6-5); longer survival duration ≥ 10 years, OR 2.2 (1.3-3.8); high BMI at diagnosis, OR 3.2 (1.5-6.9); and large delta BMI ≥ 50, OR 3.15(1.7-5.9) to be independent predictors of MetSyn. Patients who were underweight or normal at diagnosis with large delta BMI ≥ 50 had very high odds (OR, 12.5, 1.7-92) of developing MetSyn compared to those with lower delta BMI. CONCLUSIONS AND IMPLICATIONS FOR CANCER SURVIVORS: A high prevalence of MetSyn was observed in CCS with early age at onset. Timely screening and early intervention are proven to be beneficial and delta BMI could be a useful screening tool for LMIC.


Assuntos
Sobreviventes de Câncer , Síndrome Metabólica , Neoplasias , Adolescente , Índice de Massa Corporal , Criança , Países em Desenvolvimento , Humanos , Síndrome Metabólica/epidemiologia , Síndrome Metabólica/etiologia , Neoplasias/terapia , Obesidade/complicações , Fatores de Risco
17.
BMC Health Serv Res ; 22(1): 293, 2022 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-35241066

RESUMO

BACKGROUND: Public health systems internationally are under pressure to meet increasing demand for healthcare in the context of increasing financial resource constraint. There is therefore a need to maximise health outcomes achieved with public healthcare expenditure. This paper aims to establish and synthesize the contemporary evidence base for approaches taken at a system management level to improve efficiency. METHODS: Rapid Evidence Assessment (REA) methodology was employed. A search strategy was developed and applied (PUBMED, MEDLINE) returning 5,377 unique titles. 172 full-text articles were screened to determine relevance with 82 publications included in the final review. Data regarding country, study design, key findings and approaches to efficiency improvement were extracted and a narrative synthesis produced. Publications covering health systems from developed countries were included. RESULTS: Identified study designs included policy reviews, qualitative reviews, mixed methods reviews, systematic reviews, literature reviews, retrospective analyses, scoping reviews, narrative papers, regression analyses and opinion papers. While findings revealed no comprehensive frameworks for system-wide efficiency improvement, a range of specific centrally led improvement approaches were identified. Elements associated with success in current approaches included dedicated central functions to drive system-wide efficiency improvement, managing efficiency in tandem with quality and value, and inclusive stakeholder engagement. CONCLUSIONS: The requirement for public health systems to improve efficiency is likely to continue to increase. Reactive cost-cutting measures and short-term initiatives aimed only at reducing expenditure are unlikely to deliver sustainable efficiency improvement. By providing dedicated central system-wide efficiency improvement support, public health system management entities can deliver improved financial, health service and stakeholder outcomes.


Assuntos
Atenção à Saúde , Saúde Pública , Programas Governamentais , Humanos , Políticas , Estudos Retrospectivos
18.
Microsc Microanal ; : 1-15, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35702958

RESUMO

We present a fast and precise deep-learning architecture, which we term O-Net, for obtaining super-resolved images from conventional phase-modulated optical microscopical techniques, such as phase-contrast microscopy and differential interference contrast microscopy. O-Net represents a novel deep convolutional neural network that can be trained on both simulated and experimental data, the latter of which is being demonstrated in the present context. The present study demonstrates the ability of the proposed method to achieve super-resolved images even under poor signal-to-noise ratios and does not require prior information on the point spread function or optical character of the system. Moreover, unlike previous state-of-the-art deep neural networks (such as U-Nets), the O-Net architecture seemingly demonstrates an immunity to network hallucination, a commonly cited issue caused by network overfitting when U-Nets are employed. Models derived from the proposed O-Net architecture are validated through empirical comparison with a similar sample imaged via scanning electron microscopy (SEM) and are found to generate ultra-resolved images which came close to that of the actual SEM micrograph.

19.
Environ Toxicol ; 37(7): 1723-1739, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35301792

RESUMO

Benzene, a ubiquitous environmental chemical, is known to cause immune dysfunction and developmental defects. This study aims to investigate the relation between benzene-induced immune dysfunction and developmental toxicity in a genetically tractable animal model, Drosophila melanogaster. Further, the study explored the protective role of Heat Shock Protein 70 (Hsp70) against benzene-induced immunotoxicity and subsequent developmental impact. Drosophila larvae exposed to benzene (1.0, 10.0, and 100.0 mM) were examined for total hemocyte (immune cells) count, phagocytic activity, oxidative stress, apoptosis, and their developmental delay and reduction were analyzed. Benzene exposure for 48 h reduced the total hemocytes count and phagocytic activity, along with an increase in the Reactive Oxygen Species (ROS), and lipid peroxidation in the larval hemocytes. Subsequently, JNK-dependent activation of the apoptosis (Caspase-3 dependent) was also observed. During their development, benzene exposure to Drosophila larvae led to 3 days of delay in development, and ~40% reduced adult emergence. Hsp70-overexpression in hemocytes was found to mitigate benzene-induced oxidative stress and abrogated the JNK-mediated apoptosis in hemocytes, thus restoring total hemocyte count and improving phagocytotic activity. Further, hsp70-overexpression in hemocytes also lessened the benzene-induced developmental delay (rescue of 2.5 days) and improved adult emergence (~20%) emergence, revealing a possible control of immune cells on the organism's development and survival. Overall, this study established that hsp70-overexpression in the Drosophila hemocytes confers protection against benzene-induced immune injury via regulating the ROS/JNK signaling pathway, which helps in the organism's survival and development.


Assuntos
Proteínas de Choque Térmico HSP70 , Hemócitos , Animais , Apoptose , Benzeno/metabolismo , Benzeno/toxicidade , Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Larva/metabolismo , Sistema de Sinalização das MAP Quinases , Espécies Reativas de Oxigênio/metabolismo
20.
J Appl Clin Med Phys ; 23(6): e13640, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35536772

RESUMO

Plan checks are important components of a robust quality assurance (QA) program. Recently, the American Association of Physicists in Medicine (AAPM) published two reports concerning plan and chart checking, Task Group (TG) 275 and Medical Physics Practice Guideline (MPPG) 11.A. The purpose of the current study was to crosswalk initial plan check failure modes revealed in TG 275 against our institutional QA program and local incident reporting data. Ten physicists reviewed 46 high-risk failure modes reported in Table S1.A.i of the TG 275 report. The committee identified steps in our planning process which sufficiently checked each failure mode. Failure modes that were not covered were noted for follow-up. A multidisciplinary committee reviewed the narratives of 1599 locally-reported incidents in our Radiation Oncology Incident Learning System (ROILS) database and categorized each into the high-risk TG 275 failure modes. We found that over half of the 46 high-risk failure modes, six of which were top-ten failure modes, were covered in part by daily contouring peer-review rounds, upstream of the traditional initial plan check. Five failure modes were not adequately covered, three of which concerned pregnancy, pacemakers, and prior dose. Of the 1599 incidents analyzed, 710 were germane to the initial plan check, 23.4% of which concerned missing pregnancy attestations. Most, however, were caught prior to CT simulation (98.8%). Physics review and initial plan check were the least efficacious checks, with error detection rates of 31.8% and 31.3%, respectively, for some failure modes. Our QA process that includes daily contouring rounds resulted in increased upstream error detection. This work has led to several initiatives in the department, including increased automation and enhancement of several policies and procedures. With TG 275 and MPPG 11.A as a guide, we strongly recommend that departments consider an internal chart checking policy and procedure review.


Assuntos
Radioterapia (Especialidade) , Planejamento da Radioterapia Assistida por Computador , Automação , Humanos , Física , Planejamento da Radioterapia Assistida por Computador/métodos , Gestão de Riscos/métodos
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