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Proteins entering the secretory pathway need to attain native disulfide pairings to fold correctly. For proteins with complex disulfides, this process requires the reduction and isomerisation of non-native disulfides. Two key members of the protein disulfide isomerase (PDI) family, ERp57 and ERdj5 (also known as PDIA3 and DNAJC10, respectively), are thought to be required for correct disulfide formation but it is unknown whether they act as a reductase, an isomerase or both. In addition, it is unclear how reducing equivalents are channelled through PDI family members to substrate proteins. Here, we show that neither enzyme is required for disulfide formation, but ERp57 is required for isomerisation of non-native disulfides within glycoproteins. In addition, alternative PDIs compensate for the absence of ERp57 to isomerise glycoprotein disulfides, but only in the presence of a robust reductive pathway. ERdj5 is required for this alternative pathway to function efficiently indicating its role as a reductase. Our results define the essential cellular functions of two PDIs, highlighting a distinction between formation, reduction and isomerisation of disulfide bonds.
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Oxirredutases , Isomerases de Dissulfetos de Proteínas , Isomerases de Dissulfetos de Proteínas/genética , Isomerases de Dissulfetos de Proteínas/química , Isomerases de Dissulfetos de Proteínas/metabolismo , Oxirredutases/metabolismo , Dobramento de Proteína , Glicoproteínas/metabolismo , Dissulfetos/metabolismo , OxirreduçãoRESUMO
Fluorescence staining techniques, such as Cell Painting, together with fluorescence microscopy have proven invaluable for visualizing and quantifying the effects that drugs and other perturbations have on cultured cells. However, fluorescence microscopy is expensive, time-consuming, labor-intensive, and the stains applied can be cytotoxic, interfering with the activity under study. The simplest form of microscopy, brightfield microscopy, lacks these downsides, but the images produced have low contrast and the cellular compartments are difficult to discern. Nevertheless, by harnessing deep learning, these brightfield images may still be sufficient for various predictive purposes. In this study, we compared the predictive performance of models trained on fluorescence images to those trained on brightfield images for predicting the mechanism of action (MoA) of different drugs. We also extracted CellProfiler features from the fluorescence images and used them to benchmark the performance. Overall, we found comparable and largely correlated predictive performance for the two imaging modalities. This is promising for future studies of MoAs in time-lapse experiments for which using fluorescence images is problematic. Explorations based on explainable AI techniques also provided valuable insights regarding compounds that were better predicted by one modality over the other.
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Processamento de Imagem Assistida por Computador , Microscopia de Fluorescência/métodos , Células Cultivadas , Processamento de Imagem Assistida por Computador/métodosRESUMO
The effects of pH, MNP concentration, and medium viscosity on the magnetic fluid hyperthermia (MFH) properties of chitosan-coated superparamagnetic Fe3O4nanoparticles (MNPs) are probed here. Due to the protonation of the amide groups, the MNPs are colloidally stable at lower pH (â¼2), but form aggregates at higher pH (â¼8). The increased aggregate size at higher pH causes the Brownian relaxation time (τB) to increase, leading to a decrease in specific absorption rate (SAR). For colloidal conditions ensuring Brownian-dominated relaxation dynamics, an increase in MNP concentrations or medium viscosity is found to increase theτB. SAR decreases with increasing MNP concentration, whereas it exhibits a non-monotonic variation with increasing medium viscosity. Dynamic hysteresis loop-based calculations are found to be in agreement with the experimental results. The findings provide a greater understanding of the variation of SAR with the colloidal properties and show the importance of relaxation dynamics on MFH efficiency, where variations in the frequency-relaxation time product across the relaxation plateau cause significant variations in SAR. Further, thein vitrocytotoxicity studies show good bio-compatibility of the chitosan-coated Fe3O4MNPs. Higher SAR at acidic pH for bio-medically acceptable field parameters makes the bio-compatible chitosan-coated Fe3O4MNPs suitable for MFH applications.
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BACKGROUND: PD-L1 expression on cancer cells is an important mechanism of tumor immune escape, and immunotherapy targeting the PD-L1/PD1 interaction is a common treatment option for patients with melanoma. However, many patients do not respond to treatment and novel predictors of response are emerging. One suggested modifier of PD-L1 is the p53 pathway, although the relationship of p53 pathway function and activation is poorly understood. METHODS: The study was performed on human melanoma cell lines with various p53 status. We investigated PD-L1 and proteins involved in IFNγ signaling by immunoblotting and mRNA expression, as well as membrane expression of PD-L1 by flow cytometry. We evaluated differences in the ability of NK cells to recognize and kill target tumor cells on the basis of p53 status. We also investigated the influence of proteasomal degradation and protein half-life, IFNγ signaling and p53 activation on biological outcomes, and performed bioinformatic analysis using available data for melanoma cell lines and melanoma patients. RESULTS: We demonstrate that p53 status changes the level of membrane and total PD-L1 protein through IRF1 regulation and show that p53 loss influences the recently discovered SOX10/IRF1 regulatory axis. Bioinformatic analysis identified a dependency of SOX10 on p53 status in melanoma, and a co-regulation of immune signaling by both transcription factors. However, IRF1/PD-L1 regulation by p53 activation revealed complicated regulatory mechanisms that alter IRF1 mRNA but not protein levels. IFNγ activation revealed no dramatic differences based on TP53 status, although dual p53 activation and IFNγ treatment confirmed a complex regulatory loop between p53 and the IRF1/PD-L1 axis. CONCLUSIONS: We show that p53 loss influences the level of PD-L1 through IRF1 and SOX10 in an isogenic melanoma cell model, and that p53 loss affects NK-cell cytotoxicity toward tumor cells. Moreover, activation of p53 by MDM2 inhibition has a complex effect on IRF1/PD-L1 activation. These findings indicate that evaluation of p53 status in patients with melanoma will be important for predicting the response to PD-L1 monotherapy and/or dual treatments where p53 pathways participate in the overall response.
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Antígeno B7-H1 , Fator Regulador 1 de Interferon , Melanoma , Fatores de Transcrição SOXE , Transdução de Sinais , Proteína Supressora de Tumor p53 , Humanos , Fator Regulador 1 de Interferon/metabolismo , Fator Regulador 1 de Interferon/genética , Melanoma/genética , Melanoma/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteína Supressora de Tumor p53/genética , Linhagem Celular Tumoral , Antígeno B7-H1/metabolismo , Antígeno B7-H1/genética , Fatores de Transcrição SOXE/metabolismo , Fatores de Transcrição SOXE/genética , Interferon gama/metabolismo , Interferon gama/genética , Células Matadoras Naturais/metabolismo , Células Matadoras Naturais/imunologia , Regulação Neoplásica da Expressão GênicaRESUMO
BACKGROUND AND AIMS: Brassica napus is one of the most important oilseed crops worldwide. Seed yield of B. napus significantly correlates with the primary root length (PRL). The aims of this study were to identify quantitative trait loci (QTLs) for PRL in B. napus. METHODS: QTL-seq and conventional QTL mapping were jointly used to detect QTLs associated with PRL in a B. napus double haploid (DH) population derived from a cross between 'Tapidor' and 'Ningyou 7'. The identified major locus was confirmed and resolved by an association panel of B. napus and an advanced backcross population. RNA-seq analysis of two long-PRL lines (Tapidor and TN20) and two short-PRL lines (Ningyou 7 and TN77) was performed to identify differentially expressed genes in the primary root underlying the target QTLs. KEY RESULTS: A total of 20 QTLs impacting PRL in B. napus grown at a low phosphorus (P) supply were found by QTL-seq. Eight out of ten QTLs affecting PRL at a low P supply discovered by conventional QTL mapping could be detected by QTL-seq. The locus qPRL-C06 identified by QTL-seq was repeatedly detected at both an optimal P supply and a low P supply by conventional QTL mapping. This major constitutive QTL was further confirmed by regional association mapping. qPRL-C06 was delimited to a 0.77 Mb genomic region on chromosome C06 using an advanced backcross population. A total of 36 candidate genes within qPRL-C06 were identified that showed variations in coding sequences and/or exhibited significant differences in mRNA abundances in primary root between the long-PRL and short-PRL lines, including five genes involved in phytohormone biosynthesis and signaling. CONCLUSIONS: These results both demonstrate the power of the QTL-seq in rapid QTL detection for root traits and will contribute to marker-assisted selective breeding of B. napus cultivars with increased PRL.
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Brassica napus , Locos de Características Quantitativas , Locos de Características Quantitativas/genética , Brassica napus/genética , Mapeamento Cromossômico , Fenótipo , Cromossomos , Sementes/genéticaRESUMO
Breast cancers are a heterogeneous group of tumors classified according to their histological growth patterns and receptor expression characteristics. Intratumor heterogeneity also exists, with subpopulations of cells with different phenotypes found in individual cancers, including cells with stem or progenitor cell properties. At least two types of breast cancer stem cells (CSCs) exist, the epithelial and the basal/mesenchymal subtypes, although how these phenotypes are controlled is unknown. ΔNp63 is a basal cell marker and regulator of stem/progenitor cell activities in the normal mammary gland and is expressed in the basal-like CSC subpopulation in some estrogen receptor-positive (ER+) and/or human epidermal growth factor receptor 2-positive (HER2+) breast adenocarcinomas. Whilst p63 is known to directly impart CSC properties in luminal breast cancer cells, how p63 is regulated and induced in these cells is unknown. We initially confirmed the existence of a small subpopulation of ΔNp63+ cells in lymph node metastases of ER+ human ductal adenocarcinomas, indicating together with previous reports that ΔNp63+ tumor cells are present in approximately 40% of these metastases. Notably, ΔNp63+ cells show a preferential location at the edge of tumor areas, suggesting possible regulation of ΔNp63 by the tumor microenvironment. Subsequently, we showed that the high levels of ΔNp63 in basal non-transformed MCF-10A mammary epithelial cells rely on insulin in their culture medium, whilst ΔNp63 levels are increased in MCF-7 ER+ luminal-type breast cancer cells treated with insulin or insulin-like growth factor 1 (IGF-1). Mechanistically, small molecule inhibitors and siRNA gene knockdown demonstrated that induction of ΔNp63 by IGF-1 requires PI3K, ERK1/2, and p38 MAPK activation, and acts through FOXO transcriptional inactivation. We also show that metformin inhibits ΔNp63 induction. These data reveal an IGF-mediated mechanism to control basal-type breast CSCs, with therapeutic implications to modify intratumor breast cancer cell heterogeneity and plasticity.
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Adenocarcinoma , Neoplasias da Mama , Insulinas , Humanos , Feminino , Neoplasias da Mama/patologia , Fator de Crescimento Insulin-Like I , Células-Tronco/metabolismo , Células-Tronco/patologia , Microambiente TumoralRESUMO
BACKGROUND: Compared to women, South African men are less likely to know their HIV status (78% vs. 89%), have suppressed viral loads (82% vs. 90%), or access HIV prevention services. To achieve epidemic control where heterosexual sexual behavior drives transmission, interventions to improve the uptake of HIV testing services (HTS) and prevention services must also target cis-gendered, heterosexual men. There is limited understanding of these men's needs and wants with regards to accessing pre-exposure prophylaxis (PrEP). METHODS: Adult men (≥ 18 years) from a peri-urban community in Buffalo City Municipality were offered community-based HTS. Those who received a negative HIV test result were offered community-based, same-day oral PrEP initiation. Men initiating PrEP were invited to participate in a study exploring men's HIV prevention needs and reasons for initiating PrEP. An in-depth interview guide, developed using the Network-Individual-Resources model (NIRM), explored men's perceived HIV acquisition risk, prevention needs, and preferences for PrEP initiation. Interviews were conducted by a trained interviewer in isiXhosa or English, audio-recorded and transcribed. Thematic analysis was used, guided by the NIRM to generate findings. RESULTS: Twenty-two men (age range 18-57 years) initiated PrEP and consented to study participation. Men reported elevated HIV acquisition risk associated with alcohol use and condom-less sex with multiple partners as facilitators driving PrEP initiation. They anticipated social support from family members, their main sexual partner and close friends for their PrEP use, and discussed other men as important sources of support for PrEP initiation. Nearly all men expressed positive views of people using PrEP. Participants believed HIV testing would be a barrier for men interested in accessing PrEP. Men recommended that access to PrEP be convenient, rapid, and community-based (i.e., not clinic-based). DISCUSSION: Self-perceived risk for HIV acquisition was a major facilitator for men's PrEP initiation. Although men expressed positive perceptions of PrEP users, they noted that HIV testing may be a barrier to PrEP initiation. Finally, men recommended convenient access points to facilitate PrEP initiation and sustained use. Gender-responsive interventions tailored to men's needs, wants, and voices will facilitate their uptake of HIV prevention services, and help to end the HIV epidemic.
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Condução de Veículo , Infecções por HIV , Feminino , Humanos , Masculino , África do Sul/epidemiologia , Consumo de Bebidas Alcoólicas , Instituições de Assistência Ambulatorial , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controleRESUMO
Dopamine is an important neurotransmitter that regulates numerous essential functions, including cognition and voluntary movement. As such, it serves as an important scaffold for synthesis of novel analogues as part of drug development effort to obtain drugs for treatment of neurodegenerative diseases, such as Parkinson's disease. To that end, similarity search of the ZINC database based on two known dopamine-1 receptor (D1R) agonists, dihydrexidine (DHX) and SKF 38393, respectively, was used to predict novel chemical entities with potential binding to D1R. Three compounds that showed the highest similarity index were selected for synthesis and bioactivity profiling. All main synthesis products as well as the isolated intermediates, were properly characterized. The physico-chemical analyses were performed using HRESIMS, GC/MS, LC/MS with UV-Vis detection, and FTIR, 1H NMR and 13C NMR spectroscopy. Binding to D1 and D2 receptors and inhibition of dopamine reuptake via dopamine transporter were measured for the synthesized analogues of DHX and SKF 38393.
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Catecolaminas , Receptores de Dopamina D1 , 2,3,4,5-Tetra-Hidro-7,8-Di-Hidroxi-1-Fenil-1H-3-Benzazepina/farmacologia , Fenantridinas/farmacologia , Receptores de Dopamina D1/metabolismoRESUMO
BACKGROUND: Physical activity is a factor by which mental health can be improved. However, the association between mental health and physical exercise, in a "team-based sport" setting within the community, remains unclear. AIMS: The current paper aims to provide an evaluation of a football programme, implemented by Time to Change Wales, funded by the Welsh Government, to improve mental health. METHODS: Participants attended weekly 90-120 minute football sessions, held in local community venues across Wales, UK, with no requirement on the number of sessions that participants had to attend. A qualitative method was employed to explore the experiences of those who took part. RESULTS: Individuals who participated in the programme reported psychosocial and physical benefits, such as improved physical and mental health, improved social confidence and having a sense of purpose added to their day-to-day living. Factors affecting participation were also identified within the data, such as environmental barriers. Conclusion: The findings provide both support and contextual extension to previous research in this area; demonstrating the positive effects of sport-based therapy for those with mental health difficulties. Implications and conclusions should be used to inform future research into developing community sport-based programmes to improve mental health.
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Futebol Americano , Futebol , Emoções , Exercício Físico/psicologia , Humanos , Saúde MentalRESUMO
Remote digital pathology allows healthcare systems to maintain pathology operations during public health emergencies. Existing Clinical Laboratory Improvement Amendments regulations require pathologists to electronically verify patient reports from a certified facility. During the 2019 pandemic of COVID-19 disease, caused by the SAR-CoV-2 virus, this requirement potentially exposes pathologists, their colleagues, and household members to the risk of becoming infected. Relaxation of government enforcement of this regulation allows pathologists to review and report pathology specimens from a remote, non-CLIA certified facility. The availability of digital pathology systems can facilitate remote microscopic diagnosis, although formal comprehensive (case-based) validation of remote digital diagnosis has not been reported. All glass slides representing routine clinical signout workload in surgical pathology subspecialties at Memorial Sloan Kettering Cancer Center were scanned on an Aperio GT450 at ×40 equivalent resolution (0.26 µm/pixel). Twelve pathologists from nine surgical pathology subspecialties remotely reviewed and reported complete pathology cases using a digital pathology system from a non-CLIA certified facility through a secure connection. Whole slide images were integrated to and launched within the laboratory information system to a custom vendor-agnostic, whole slide image viewer. Remote signouts utilized consumer-grade computers and monitors (monitor size, 13.3-42 in.; resolution, 1280 × 800-3840 × 2160 pixels) connecting to an institution clinical workstation via secure virtual private network. Pathologists subsequently reviewed all corresponding glass slides using a light microscope within the CLIA-certified department. Intraobserver concordance metrics included reporting elements of top-line diagnosis, margin status, lymphovascular and/or perineural invasion, pathology stage, and ancillary testing. The median whole slide image file size was 1.3 GB; scan time/slide averaged 90 s; and scanned tissue area averaged 612 mm2. Signout sessions included a total of 108 cases, comprised of 254 individual parts and 1196 slides. Major diagnostic equivalency was 100% between digital and glass slide diagnoses; and overall concordance was 98.8% (251/254). This study reports validation of primary diagnostic review and reporting of complete pathology cases from a remote site during a public health emergency. Our experience shows high (100%) intraobserver digital to glass slide major diagnostic concordance when reporting from a remote site. This randomized, prospective study successfully validated remote use of a digital pathology system including operational feasibility supporting remote review and reporting of pathology specimens, and evaluation of remote access performance and usability for remote signout.
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Infecções por Coronavirus , Pandemias , Patologia Cirúrgica , Pneumonia Viral , Telepatologia , Betacoronavirus , COVID-19 , Humanos , Processamento de Imagem Assistida por Computador/métodos , Patologia Cirúrgica/instrumentação , Patologia Cirúrgica/métodos , Patologia Cirúrgica/organização & administração , SARS-CoV-2 , Telepatologia/instrumentação , Telepatologia/métodos , Telepatologia/organização & administração , Fluxo de TrabalhoRESUMO
Considerable genetic variation in agronomic nitrogen (N) use efficiency (NUE) has been reported among genotypes of Brassica napus. However, the physiological and molecular mechanisms underpinning these differences remain poorly understood. In this study, physiological and genetic factors impacting NUE were identified in field trials and hydroponic experiments using two B. napus genotypes with contrasting NUE. The results showed that the N-efficient genotype (D4-15) had greater N uptake and utilization efficiencies, more root tips, larger root surface and root volume, and higher N assimilation and photosynthesis capacity than the N-inefficient genotype (D2-1). Genomic analysis revealed that D4-15 had a greater genome diversity related to NUE than D2-1. By combining genomic and transcriptomic analysis, genes involved in photosynthesis and C/N metabolism were implicated in conferring NUE. Co-expression network analysis of genes that differed between the two genotypes suggested gene clusters impacting NUE. A nitrate transporter gene BnaA06g04560D (NRT2.1) and two vacuole nitrate transporter CLC genes (BnaA02g11800D and BnaA02g28670D) were up-regulated by N starvation in D4-15 but not in D2-1. The study revealed that high N uptake and utilization efficiencies, maintained photosynthesis and coordinated C/N metabolism confer high NUE in B. napus, and identified candidate genes that could facilitate breeding for enhanced NUE in B. napus.
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Brassica napus/genética , Perfilação da Expressão Gênica , Genoma de Planta , Nitrogênio/metabolismo , Aminoácidos/metabolismo , Proteínas de Transporte de Ânions/genética , Proteínas de Transporte de Ânions/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Brassica napus/efeitos dos fármacos , Carbono/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Redes Reguladoras de Genes/efeitos dos fármacos , Variação Genética/efeitos dos fármacos , Genótipo , Hidroponia , Transportadores de Nitrato , Nitrogênio/farmacologia , Fotossíntese/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ribulose-Bifosfato Carboxilase/metabolismo , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Solubilidade , Soluções , Açúcares/metabolismo , Transcrição Gênica/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Transcriptoma/genéticaRESUMO
This multi-institutional study retrospectively evaluated clinicopathologic and genetic characteristics in 351 patients with core-binding-factor acute myeloid leukemia (CBF-AML), comprising 69 therapy-related (t-CBF-AML) and 282 de novo cases. The T-CBF-AML patients were older, had lower WBC counts, and slightly higher hemoglobin than patients with de novo disease. Secondary cytogenetic abnormalities were more frequent in patients with de novo disease than t-CBF-AML (57.1% vs 41.1%, P = .026). Patients with secondary cytogenetic abnormalities had longer overall survival (OS) than those without abnormalities (median 190 vs 87 months, P = .021); trisomy 8, trisomy 22, and loss of the X or Y chromosome were associated with longer OS. In the 165 cases performed of targeted gene sequencing, pathogenic mutations were detected in 75.7% of cases, and were more frequent in de novo than in therapy-related disease (P = .013). Mutations were found in N/KRAS (37.0%), FLT3 (27.8%), KIT (17.2%), TET2 (4.9%), and ASXL1 (3.9%). The TET2 mutations were associated with shorter OS (P = .012) while N/KRAS mutation was associated with longer OS in t(8;21) AML patients (P = .001). The KIT mutation did not show prognostic significance in this cohort. Although they received similar therapy, t-CBF-AML patients had shorter OS than de novo patients (median 69 vs 190 months, P = .038). In multivariate analysis of all patients, older age and absence of any secondary cytogenetic abnormalities were significant predictors of shorter OS. Among the t-CBF-AML subset, age and hemoglobin were significant on multivariate analysis. This study demonstrated that although de novo and t-CBF-AML patients share many features, t-CBF-AML patients have worse clinical outcome than de novo patients.
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Aberrações Cromossômicas , Fatores de Ligação ao Core , Leucemia Mieloide Aguda , Proteínas de Neoplasias , Adulto , Fatores de Ligação ao Core/genética , Fatores de Ligação ao Core/metabolismo , Intervalo Livre de Doença , Feminino , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/mortalidade , Leucemia Mieloide Aguda/terapia , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Estudos Retrospectivos , Taxa de SobrevidaRESUMO
We provide the first experimental evidence for soft glassy behavior in a sterically stabilized magnetic colloid (ferrofluid) of relatively low volume fraction (φ = 0.037) when a uniform magnetic field is applied at a sufficiently high rate (fast quench). Fast magnetic-field quenches favor structural arrest of field-induced aggregates, owing to insufficient time to settle into lower energy states, thereby pushing the system to a frustrated metastable configuration like a repulsive glass. Brownian dynamics simulations are used to show that the polydisperse ferrofluid (as in experiments) forms thick ropes aligned along the field direction, while a monodisperse ferrofluid does not. The simulations show that there is practically no ordering of the thin, monodisperse chains, while the thick, polydisperse ropes show positional ordering with a typical center-center separation between the particles in different ropes of about 0.39 µm. As a consequence of structural arrest, the ferrofluid exhibits aging with broken time-translational invariance, a hallmark of glassy dynamics. The superposition of strain and creep compliance curves obtained from rheological measurements at different waiting times in the effective time domain corroborates the soft glassy behavior when exposed to a magnetic field applied at a fast ramp rate.
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Thermoregulatory control of human body temperature is of paramount importance for normal bodily functions. Exposure of the upper and lower limbs to localized cold stress can cause cold-induced injuries and often lower limbs are more susceptible to damages from cold-induced injuries. In this study, we use infrared thermal imaging to probe localized cold stress induced cutaneous vasoconstriction of lower limbs in 33 healthy subjects. The cold stress is actuated by applying ice to the plantar surfaces of the lower limbs for 180 s and after removal of the cold stress, infrared thermography is utilized to non-invasively monitor the time-dependent variations in vein pixel temperatures on the dorsal surfaces of the stimulated and non-stimulated feet. It is observed that the vein pixel temperature of the stimulated foot showed a non-monotonic variation with time, consisting of an initial decrease and the presence of an inversion time, beyond which temperature is regained. The initial decrease in vein pixel temperature of the stimulated foot is attributed to the reduced blood flow caused by the cold stress induced severe vasoconstriction. Beyond the inversion time, the vein pixel temperature is found to increase due to rewarming of the surrounding skin. Experimental findings indicate that the inversion time linearly increased with the age of the subject, indicating a reduced thermoregulatory efficiency for the aged subjects. This study provides a thermal imaging-based insight into the skin temperature re-distribution during the early stages of blood perfusion in lower limbs, after an exposure to a localized acute cold stress. Statistical analyses reveal that subject height, weight, body-mass index and gender do not influence the inversion time significantly. The experimental findings are important towards rapid evaluation of personnel fitness for deployment in extreme cold environment, treatment of cold-induced injuries and probing of thermoregulatory impairments.
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Envelhecimento/fisiologia , Regulação da Temperatura Corporal , Resposta ao Choque Frio/fisiologia , Extremidade Inferior/fisiologia , Adolescente , Adulto , Feminino , Humanos , Raios Infravermelhos , Masculino , Pessoa de Meia-Idade , Termografia , Adulto JovemRESUMO
The purpose of this study is to examine hematopoietic neoplasms with 9p24/JAK2 rearrangement including neoplasms associated with t(8;9)(p22;p24)/PCM1-JAK2 fusion neoplasm as well as cases with translocations involving 9p24/JAK2 and other partner genes. From seven large medical centers, we identified ten patients with t(8;9)(p22;p24) /PCM1-JAK2 and 3 with t(9p24;v)/JAK2 at diagnosis. Majority of the cases showed myeloproliferative neoplasm (MPN) associated features (n = 7) characterized by variable degrees of eosinophilia, myelofibrosis, frequent proliferations of early erythroblasts in bone marrow and extramedullary sites, and infrequent/absent somatic mutations. Other less common presentations included myelodysplastic syndromes (MDS) or MDS/MPN (one each). Four patients presented with B-lymphoblastic leukemia (B-ALL), and of them, two patients with t(8;9)(p22;p24.1) were proven to be B-lymphoblastic crisis of MPN; and the other two cases with t(9p24;v) both were de novo B-ALL, BCR-ABL1-like (Ph-like). We show that the hematopoietic neoplasms with 9p24/JAK2 rearrangement are extremely rare, and most of them are associated with t(8;9)(p22;p24)/PCM1-JAK2, a recent provisional World Health Organization entity under "myeloid/lymphoid neoplasm with a specific gene rearrangement". Cases of t(8;9)(p22;p24)/PCM1-JAK2, though heterogeneous, do exhibit some common clinicopathological characteristic features. Cases with t(9p24;v)/JAK2 are extremely rare; while such cases with a MPN presentation may resemble t(8;9)(p22;p24.1)/PCM1-JAK2, B-ALL cases presenting de novo B-ALL might belong to Ph-like B-ALL.
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Cromossomos Humanos Par 9/genética , Neoplasias Hematológicas/genética , Janus Quinase 2/genética , Proteínas de Fusão Oncogênica/genética , Adulto , Feminino , Rearranjo Gênico , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Acute undifferentiated leukemia is a rare type of acute leukemia that shows no evidence of differentiation along any lineage. Clinical, immunophenotypic and genetic data is limited and it is uncertain if acute undifferentiated leukemia is biologically distinct from acute myeloid leukemia with minimal differentiation, which also shows limited myeloid marker expression and has been reported to have a poor prognosis. We identified 92 cases initially diagnosed as acute undifferentiated leukemia or acute myeloid leukemia with minimal differentiation from pathology databases of nine academic institutions with available diagnostic flow cytometric data, cytogenetic findings, mutational and clinical data. Outcome analysis was performed using Kaplan Meier test for the 53 patients who received induction chemotherapy. Based on cytogenetic abnormalities (N = 30) or history of myelodysplastic syndrome (N = 2), 32 cases were re-classified as acute myeloid leukemia with myelodysplasia related changes. The remaining 24 acute undifferentiated leukemia patients presented with similar age, blood counts, bone marrow cellularity, and blast percentage as the remaining 30 acute myeloid leukemia with minimal differentiation patients. Compared to acute myeloid leukemia with minimal differentiation, acute undifferentiated leukemia cases were characterized by more frequent mutations in PHF6 (5/15 vs 0/19, p = 0.016) and more frequent expression of TdT on blasts (p = 0.003) while acute myeloid leukemia with minimal differentiation cases had more frequent CD123 expression (p = 0.042). Outcome data showed no difference in overall survival, relapse free survival, or rates of complete remission between acute undifferentiated leukemia and acute myeloid leukemia with minimal differentiation groups (p > 0.05). Acute myeloid leukemia with myelodysplasia-related changes patients showed shorter survival when censoring for bone marrow transplant as compared to acute undifferentiated leukemia (p = 0.03) and acute myeloid leukemia with minimal differentiation (p = 0.002). In this largest series to date, the acute undifferentiated leukemia group shows distinct characteristics from acute myeloid leukemia with minimal differentiation, including more frequent PHF6 mutations and expression of TdT.
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Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Leucemia/genética , Leucemia/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Genótipo , Humanos , Imunofenotipagem , Leucemia/classificação , Leucemia Mieloide Aguda/classificação , Masculino , Pessoa de Meia-IdadeRESUMO
The corrosion of ferritic steel, a widely used structural material in the power and nuclear industries exposed to humid coastal environments, is a major concern. Here, we present a template-free one-step electrodeposition method for the fabrication of a robust superhydrophobic (SHP) coating on ferritic steel with excellent mechanical stability, enhanced corrosion resistance, and self-cleaning ability. By varying the electrodeposition time and potential, the micronanoscale hierarchical surface structures were optimized. The coated SHP surfaces were characterized by water contact angle measurement, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The coated surfaces showed a characteristic cauliflower morphology of cerium myristate with micronanoscale features. The maximum water contact angle achieved was 162.8 ± 2.4°. Shear abrasion testing showed good mechanical durability for the prepared coatings. The as-prepared SHP coating showed a five order reduction in corrosion current density (4.14 × 10-11 A/cm2) and corrosion rate (4.63 × 10-7 mm/y) as compared to the bare sample. Further, a six order enhancement in the polarization resistance (1.55 × 109 Ω) was also observed in agressive chloride solution, which confirmed the excellent corrosion resistance of the SHP coating. Electrochemical impedance spectroscopy (EIS) studies showed a high impedance modulus for SHP coated surfaces due to the presence of a compact protective layer of cerium myristate. This observed impedance modulus of the SHP surface was approximately four orders higher than the reported value on magnesium alloys. This study provides a new platform for obtaining a robust, mechanically stable, and corrosion resistant SHP coating with a self-cleaning ability on ferritic steel substrates that may be adapted for a range of materials in practical applications.
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1. The utility of 1-aminobenzotriazole (ABT), incorporated in food, has been investigated as an approach for longer term inhibition of cytochrome P450 (P450) enzymes in mice. 2. In rats, ABT inhibits gastric emptying, to investigate this potential limitation in mice we examined the effect of ABT administration on the oral absorption of NVS-CRF38. Two hour prior oral treatment with 100 mg/kg ABT inhibited the oral absorption of NVS-CRF38, Tmax was 4 hours for ABT-treated mice compared to 0.5 hours in the control group. 3. A marked inhibition of hepatic P450 activity was observed in mice fed with ABT containing food pellets for 1 month. P450 activity, as measured by the oral clearance of antipyrine, was inhibited on day 3 (88% of control), week 2 (83% of control) and week 4 (80% of control). 4. Tmax values for antipyrine were comparable between ABT-treated mice and the control group, alleviating concerns about impaired gastric function. 5. Inclusion of ABT in food provides a minimally invasive and convenient approach to achieve longer term inhibition of P450 activity in mice. This model has the potential to enable pharmacological proof-of-concept studies for research compounds which are extensively metabolised by P450 enzymes.
Assuntos
Inibidores das Enzimas do Citocromo P-450/farmacologia , Sistema Enzimático do Citocromo P-450/metabolismo , Triazóis/farmacologia , Administração Oral , Animais , Camundongos , Oxazóis/metabolismo , Pirazóis/metabolismoRESUMO
We report a novel approach to enhance thermal stability of magnetite nanoparticles by entrapping them in silver matrix. The oleic acid capped nanoparticles of average crystallite size Ë10 nm were synthesized through co-precipitation, followed by hydrothermal microwave assisted capping of magnetite nanoparticles with Ag matrix in ethylene glycol solvent. At Ë160 °C the oleic acid is desorbed from the magnetite nanoparticles, and silver is deposited on negatively charged magnetite seeds through electrostatic attraction. The prepared particles are characterized by X-ray diffraction, high resolution transmission electron microscopy, dynamic light scattering and UV-vis spectroscopy. The surface plasmon resonance band at 479 nm and large average hydrodynamic diameter of Ë432 nm confirm the Ag matrix around the magnetite particles. Thermal stability of prepared particles was assessed using in situ high temperature XRD, thermo gravimetric analysis and differential scanning calorimetry and the results are compared with that of oleic acid capped particles. Magnetite nanoparticles in silver matrix showed no phase conversion up to 900 °C, while oleic acid capped and bare nanoparticles are phase converted to nonmagnetic α-Fe2O3 phase between 400-450 °C, under vacuum annealing. A rapid growth of Fe3O4 nanoparticles at higher temperature was observed due to faster coalescence through diffusion and higher surface free energy of magnetite as compared to silver. The saturation magnetization of oleic acid capped magnetite particles in silver matrix before and after vacuum annealing at 900 °C were 25.4 and 46.7 emu/g, respectively. The retention of superparamagnetic behavior in silver matrix up to 900 °C is interesting for high temperature applications.
RESUMO
Metabolic profiling of Glycyrrhiza glabra using comprehensive two-dimensional liquid chromatography (LC × LC) coupled with photodiode array (PDA) and mass spectrometry (MS) detection is described. The separation was conducted under reversed-phase conditions, using a combination of first dimension (1 D) 150 mm microbore cyano column utilising 2.7 µm diameter (dp ) particles, and second dimension (2 D) 50 mm superficially porous octadecylsilica column with 2.7 µm dp particles. A multi-segmented shift gradient (MSG) for the 2 D separation was developed, and the orthogonality achieved was compared with other modes of gradients, such as full in-fraction, and shift gradient systems. Results demonstrated a significant expansion of metabolic coverage using MSG in 2 D, providing the highest measure of orthogonality compared to other gradient modes. Compound identifications were performed by employing complementary data from PDA and MS detection, with reference to structural group-type distribution in 2D space. A total of ca. 120 compounds were detected, and among them 37 were tentatively identified, distributed over the chemical families of glycosylated flavanones, triterpene saponins, and others. In comparison with one-dimensional LC, the total number of compounds detected was ca. 2-fold greater when LC × LC was employed. To the best of our knowledge, this is the first demonstration of the MSG mode in LC × LC, representing a powerful strategy to expand the metabolic coverage for analysis of plant-derived extracts, containing a multitude of different phytochemical classes.