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1.
Soft Matter ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38973240

RESUMO

Soft materials are characterized by their intricate interplay of structure, dynamics, and rheological properties. This complexity makes it challenging to accurately predict their response to shear stress. Here, we investigate how the nature of bonds - electrostatic attractions, physical entanglements, physical repulsion, and covalent bonds - affects the linear and nonlinear rheology of gels. Specifically, we determine the critical roles these bonds play in the yield transition and thixotropic recovery of gel properties through a combination of linear oscillatory deformations, serial creep divergence measurements, and time-resolved flow sweeps. Different classes of gels are prepared with nearly identical linear rheology but significantly different yield transitions and nonlinear properties post-yielding. These differences are directly related to the kinetics by which the underlying elastic networks rebuild after flow. Gels which exhibit thixotropic hysteresis are able to fully recover their yield stress over time while non-thixotropic gels possess time-independent yielding metrics. This direct comparison between thixotropy and yielding reveals the intimate relationship between these phenomena and their controlling physical mechanisms within soft, amorphous materials.

2.
BMJ Case Rep ; 17(6)2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38839419

RESUMO

We detail a case of a woman in her 40s with isolated melanoma skeletal muscle metastasis (MSMM) to the right psoas muscle. This patient underwent R0 surgical resection through a novel pelvic approach. She received subsequent adjuvant immunotherapy with Braftovi/Mektov along with adjuvant radiation. She is currently disease free at 9 months post surgery. Here, we describe our novel surgical approach including description of the tumour pathology. We explain our multidisciplinary management of MSMM consisting of a multidisciplinary surgical approach by surgical oncology, gynecological oncology and urology as well as multidisciplinary medical management by oncology, radiation oncology and pathology. Finally, we discuss best current options for therapeutic management.


Assuntos
Melanoma , Neoplasias Musculares , Músculos Psoas , Humanos , Melanoma/secundário , Melanoma/patologia , Melanoma/terapia , Feminino , Músculos Psoas/diagnóstico por imagem , Músculos Psoas/patologia , Neoplasias Musculares/secundário , Neoplasias Musculares/diagnóstico por imagem , Neoplasias Musculares/terapia , Adulto , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/secundário
3.
Mil Med ; 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38829165

RESUMO

INTRODUCTION: A light-weight pneumatic-powered knee exoskeleton could augment mobility and lifting capabilities for a variety of occupational settings. However, added weight/bulkiness and artificially produced knee extension torque could compromise sensorimotor characteristics. MATERIALS AND METHODS: Ten healthy participants conducted 3 visits within 10 days to the biomechanics laboratory. Participants were asked to complete the following tasks on each visit: single-leg balance, single-leg drop-landing, and select functional movement tasks. Balance characteristics (the ground reaction forces variability and center-of-pressure velocity) were derived from force plates while knee flexion angles during drop-landing and functional movement tasks were captured using a motion capture system. Descriptive statistics as well as paired t-tests or Wilcoxon signed-rank tests were used to compare between conditions. Significance was set at P < .05 a priori. RESULTS: During single-leg balance, the ground reaction force variabilities were significantly increased (P = .013-.019) and the center of pressure velocity was decreased (P = .001-.017) when wearing knee exoskeleton. During single-leg drop-landing, the exoskeleton condition showed lower knee flexion angles at the initial contact (P = .004-.021) and peak (P = .006-.010). Additionally, the peak vertical ground reaction force was higher in the exoskeleton condition (P = .007). During functional movement tasks, the exoskeleton condition showed less knee flexion range-of-motion during the overhead squat (P = .007-.033) and hurdle step-over (P = .004-.005). CONCLUSIONS: Participants exhibited stiffer landing technique with the exoskeleton. Given that these compromised sensorimotor characteristics have been associated with musculoskeletal injury risk, modifications to exoskeletons to promote softer landing and greater knee flexion range-of-motion during dynamic activities may be warranted.

4.
Genetics ; 225(2)2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37594076

RESUMO

Autophagy, an autophagosome and lysosome-based eukaryotic cellular degradation system, has previously been implicated in lifespan regulation in different animal models. In this report, we show that expression of the RNAi transgenes targeting the transcripts of the key autophagy genes Atg1 or Atg18 in adult fly muscle or glia does not affect the overall levels of autophagosomes in those tissues and does not change the lifespan of the tested flies but the lifespan reduction phenotype has become apparent when Atg1 RNAi or Atg18 RNAi is expressed ubiquitously in adult flies or after autophagy is eradicated through the knockdown of Atg1 or Atg18 in adult fly adipocytes. Lifespan reduction was also observed when Atg1 or Atg18 was knocked down in adult fly enteroblasts and midgut stem cells. Overexpression of wild-type Atg1 in adult fly muscle or adipocytes reduces the lifespan and causes accumulation of high levels of ubiquitinated protein aggregates in muscles. Our research data have highlighted the important functions of the key autophagy genes in adult fly adipocytes, enteroblasts, and midgut stem cells and their undetermined roles in adult fly muscle and glia for lifespan regulation.


Assuntos
Proteína Homóloga à Proteína-1 Relacionada à Autofagia , Autofagia , Proteínas de Drosophila , Drosophila melanogaster , Longevidade , Animais , Autofagia/genética , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/genética , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Longevidade/genética , Interferência de RNA
5.
Angew Chem Int Ed Engl ; 62(27): e202304173, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37132083

RESUMO

Constructing photocatalyst systems to functionalize the inert C-H bonds has attracted extensive research interest. However, purposeful modulation of interfacial charge transfer in heterostructures remains a challenge, as it usually suffers from sluggish kinetics. Reported herein is an easy strategy to construct the heteroatom-induced interface for developing the titanium-organic frameworks (MOF-902) @ thiophene-based covalent triazine frameworks (CTF-Th) nanosheets S-scheme heterojunctions with controllable oxygen vacancies (OVs). Specifically, Ti atoms were first anchored onto the heteroatom site of CTF-Th nanosheets, and then grown into MOF-902 via an interfacial Ti-S linkage, generating OVs. Using in situ X-ray photoelectron spectroscopy (XPS), extended X-ray absorption fine structure (EXAFS) spectroscopy and density functional theory (DFT) calculations, the enhanced interfacial charge separation and transfer induced by moderate OVs in the pre-designed S-scheme nanosheets was validated. The heterostructures exhibited an improved efficiency in photocatalytic C3-acylation of indoles under mild conditions with a yield 8.2 times larger than pristine CTF-Th or MOF-902 and enabled an extended scope of substrates (15 examples). This performance is superior to state-of-the-art photocatalyst and can be retained, without significant loss, after 12 consecutive cycles.

6.
J Neurol ; 270(6): 3138-3158, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36892629

RESUMO

BACKGROUND AND PURPOSE: Myotonic dystrophy type 1 (DM1) is the most common form of adult-onset muscular dystrophy and is caused by an repeat expansion [r(CUG)exp] located in the 3' untranslated region of the DMPK gene. Symptoms include skeletal and cardiac muscle dysfunction and fibrosis. In DM1, there is a lack of established biomarkers in routine clinical practice. Thus, we aimed to identify a blood biomarker with relevance for DM1-pathophysiology and clinical presentation. METHODS: We collected fibroblasts from 11, skeletal muscles from 27, and blood samples from 158 DM1 patients. Moreover, serum, cardiac, and skeletal muscle samples from DMSXL mice were included. We employed proteomics, immunostaining, qPCR and ELISA. Periostin level were correlated with CMRI-data available for some patients. RESULTS: Our studies identified Periostin, a modulator of fibrosis, as a novel biomarker candidate for DM1: proteomic profiling of human fibroblasts and murine skeletal muscles showed significant dysregulation of Periostin. Immunostaining on skeletal and cardiac muscles from DM1 patients and DMSXL mice showed an extracellular increase of Periostin, indicating fibrosis. qPCR studies indicated increased POSTN expression in fibroblasts and muscle. Quantification of Periostin in blood samples from DMSXL mice and two large validation cohorts of DM1 patients showed decreased levels in animals and diseased individuals correlating with repeat expansion and disease severity and presence of cardiac symptoms identified by MRI. Analyses of longitudinal blood samples revealed no correlation with disease progression. CONCLUSIONS: Periostin might serve as a novel stratification biomarker for DM1 correlating with disease severity, presence of cardiac malfunction and fibrosis.


Assuntos
Cardiomiopatias , Distrofia Miotônica , Adulto , Humanos , Camundongos , Animais , Distrofia Miotônica/genética , Expansão das Repetições de Trinucleotídeos , Proteômica , Músculo Esquelético , Células Musculares/metabolismo , Cardiomiopatias/genética , Cardiomiopatias/metabolismo , Gravidade do Paciente , Miotonina Proteína Quinase/genética
7.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-984487

RESUMO

INTRODUCTION@#Ovarian cancer is one of the leading causes of mortality in women. In 2020, 5,395 (6.2%) of diagnosed malignancies in females were ovarian in origin. It also ranked second among gynecologic malignancies after cervical cancer. The prevalence in Asian /Pacific women is 9.2 per 100,000 population. Increased mortality and poor prognosis in ovarian cancer are caused by asymptomatic growth and delayed or absent symptoms for which about 70% of women have an advanced stage (III/IV) by the time of diagnosis. The most associated gene mutations are Breast Cancer gene 1 (BRCA1) which is identified in chromosome 17q21 and Breast Cancer gene 2 (BRCA2) identified in chromosome 13. Both proteins function in the double-strand DNA break repair pathway especially in the large framework repair molecules. Olaparib is a first-line drug used in the management of ovarian cancer. It targets affected cells by inhibition of poly (ADP-ribose) polymerase (PARP) activity which induces synthetic lethality in mutated BRCA1/2 cancers by selectively targeting tumor cells that fail to repair DNA double-strand breaks (DSBs).@*OBJECTIVE@#The study aims to determine the prevalence of pathogenic somatic mutations in BRCA1 and BRCA2 among patients diagnosed of having ovarian cancer, to characterize the identified variants into benign/ no pathogenic variant identified, variant of uncertain significance (VUS), and pathogenic, and to determine the relationship of specific mutations detected with histomorphologic findings and clinical attributes.@*METHODOLOGY@#Ovarian cancer tissues available at the St. Luke’s Medical Center Human Cancer Biobank and formalin-fixed paraffin-embedded (FFPE) tissue blocks diagnosed as ovarian cancer from the year 2016 to 2020 were included. Determination of the prevalence of somatic BRCA1 and BRCA2 mutations using Next Generation Sequencing (NGS).@*RESULTS@#A total of 60 samples were processed, and three samples were excluded from the analysis due to an inadequate number of cells. In the remaining 57 samples diagnosed ovarian tumors, pathogenic BRCA1/2 variants were identified in 10 (17.5%) samples. Among the BRCA1/2 positive samples, 3 (5.3%) BRCA1 and 7 (12.3%) BRCA2 somatic mutations were identified.@*CONCLUSION@#Identification of specific BRCA1/2 mutations in FFPE samples with NGS plays a big role in the management of ovarian cancer, particularly with the use of targeted therapies such as Olaparib. The use of this drug could provide a longer disease-free survival for these patients. Furthermore, we recommend that women diagnosed with ovarian cancer should be subjected to genetic testing regardless of the histologic subtypes or clinical features. Lastly, genetic testing should be done along with proper genetic counseling, especially for patients who are susceptible to these mutations.


Assuntos
Neoplasias Ovarianas
8.
Int J Qual Health Care ; 34(4)2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36416545

RESUMO

BACKGROUND: The physical therapy (PT) department at a level 1 trauma center identified vendor delivery delays of off-the-shelf (OTS) spinal orthoses that delayed patient mobilization. OBJECTIVE: This study aimed to identify improvements in mobilization times, discharge times and reduction in the cost of care after centralizing the management of orthoses within the therapy department. METHOD: The centralized management of OTS spinal orthoses included stocking three adjustable lumbosacral and thoraco-lumbosacral orthosis sizes and ensuring that all personnel received training to appropriately fit the orthoses to patients. This study evaluates the impact of the centralized program by using a retrospective interrupted time-series design to compare outcomes before and after program implementation. Outcome measurements included orthosis delivery delay, time to orthosis delivery, time to mobilization by physical therapist, length of stay (LOS) and cost of care. Segmented linear regression, Wilcoxon rank-sum test and Fisher's exact tests compared outcome measures before and after implementing the centralized program. RESULTS: The PT-managed program eliminated orthosis delivery delays noted during the vendor program (42 vs. 0; P < 0.001), resulting in an overall 13.97-h reduction in time to mobilization (P < 0.001). Program cost savings equated to $2,023.40 per patient (P < 0.001). Sub-group analysis of patients without complications and treated conservatively showed a significant reduction in LOS (15.36 h; P = 0.009) in addition to time to mobilization reductions. CONCLUSION: The PT-managed program significantly improved the quality of care for patients who required a spinal orthosis by mobilizing patients as soon as possible, allowing timely discharge. The program also resulted in overall patient and hospital cost savings.


Assuntos
Aparelhos Ortopédicos , Modalidades de Fisioterapia , Humanos , Estudos Retrospectivos , Tempo de Internação , Hospitais
9.
World J Urol ; 40(10): 2561-2566, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36001137

RESUMO

INTRODUCTION AND OBJECTIVES: This Swiss LithoClast® Trilogy lithotrite is a new lithotrite for percutaneous nephrolithotomy (PCNL). It has four modifiable settings; impact, frequency, ultrasound and suction. We aim to determine the optimal device settings for the fastest stone clearance. MATERIALS AND METHODS: Kidney stone phantoms were made with Begostone in a powder to water ratio (15:3-15:6). Complete stone clearance (seconds) was calculated and impact and frequency were adjusted and repeated N = 3. Intra renal pressure (IRP) was then measured in a porcine kidney model. RESULTS: Stone phantoms with physical properties similar to struvite were cleared best with 100% impact and frequency of 12 Hz. Both uric acid stone phantoms and calcium phosphate stone phantoms were cleared most efficiently with an impact of 30% and a frequency of 4 Hz. The mean time to clear uric acid stone phantoms was 83 s versus 217 s for calcium phosphate stone phantoms. Similarly, for calcium oxalate stone phantoms, an impact of 30% and a frequency of 4 Hz was associated with the fastest clearance time, mean 204 s. However, the differences between 4, 8 and 12 Hz were not statistically significant. At a suction level of 60% or higher, IRP became negative. CONCLUSION: These results indicate that stone phantoms of hard kidney stones are cleared more efficiently at lower impact and frequency settings. With regard to suction, a setting of ≤ 50% appears to be the optimal setting.


Assuntos
Cálculos Renais , Nefrostomia Percutânea , Animais , Oxalato de Cálcio , Cálculos Renais/cirurgia , Pós , Estruvita , Suínos , Ácido Úrico , Água
10.
Pan Afr Med J ; 41: 3, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35145595

RESUMO

INTRODUCTION: many studies have shown that unimproved water sources, inadequate sanitation facilities and poor hygiene are the main causes of diarrheal diseases, especially in developing countries. The aim of this study was to determine the prevalence and risk factors associated with diarrheal diseases in Sierra Leone. METHODS: a cross-sectional study was conducted in March 2019. We used a questionnaire to collect data from study participants. Descriptive statistical analysis was followed to determine frequencies and percentages. Univariate analysis was used to find any association between dependent variable and independent variables. Independent variables that had an association in univariate were included in the multivariate model. RESULTS: we surveyed 1,002 households (516 in rural and 486 in urban), and 2,311 respondents in four districts. The main source of income was farming 437 (43.6%). A total of 49 (54.2%) households earned below the national minimum wage per month. Females represented 61.9% of respondents. A total of 242 (32.2%) households had one to five household members and 229 (30.5%) households had more than ten members. Around 88.9% of households in urban, and 42.2% rural areas use improved water sources. The prevalence of diarrheal diseases was 12.3%. Multivariate analysis showed that using of unimproved water sources (aOR=1.9; 95% CI, 1.01 to 3.63, p=0.045), and large family size (aOR= 2.5; 95% CI, 1.18 to 5.35, p=0.017) were associated with diarrheal disease. CONCLUSION: we concluded that the risk factors associated with diarrheal diseases included unimproved water sources and large family size. More efforts required to improve water resources, adequate sanitation, and hygiene, particularly in rural areas.


Assuntos
Diarreia , Saneamento , Estudos Transversais , Diarreia/epidemiologia , Feminino , Humanos , Prevalência , Fatores de Risco , Serra Leoa/epidemiologia
11.
Hemodial Int ; 26(1): 83-93, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34378315

RESUMO

INTRODUCTION: Coronavirus disease 2019 (COVID-19) adversely affects patients who are older, multimorbid, and from Black, Asian or minority ethnicities (BAME). We assessed whether being from BAME is independently associated with mortality in end-stage kidney disease (ESKD) patients with COVID-19. METHODS: Prospective observational study in a single UK renal center. A study was conducted between March 10, 2020 and April 30, 2020. Demographics, socioeconomic deprivation (index of multiple deprivation), co-morbidities (Charlson comorbidity index [CCI]), and frailty data (clinical frailty score) were collected. The primary outcome was all-cause mortality. Data were censored on the 1st June 2020. FINDINGS: Overall, 191 of our 3379 ESKD patients contracted COVID-19 in the 8-week observation period; 84% hemodialysis, 5% peritoneal dialysis, and 11% kidney transplant recipients (KTR). Of these, 57% were male and 67% were from BAME groups (43% Asian, 17% Black, 2% mixed race, and 5% other). Mean CCI was 7.45 (SD 2.11) and 3.90 (SD 2.10) for dialysis patients and KTR, respectively. In our cohort, 60% of patients lived in areas classified as being in the most deprived 20% in the United Kingdom, and of these, 77% of patients were from BAME groups. The case fatality rate was 29%. Multivariable cox regression demonstrated that BAME (hazard ratio [HR]: 2.37, 95% CI: 1.22-4.61) was associated with all-cause mortality after adjustment for age, deprivation, co-morbidities, and frailty. Associations with all-cause mortality persisted in sensitivity analyses in patients from South Asian (HR: 2.52, 95% CI: 1.24-5.12) and Black (HR: 2.43, 95% CI: 1.04-5.67) ethnic backgrounds. DISCUSSION: BAME ESKD patients with COVID-19 are just over twice as likely to die compared to White patients, despite adjustment for age, deprivation, comorbidity, and frailty. This study highlights the need to develop strategies to improve BAME patient outcomes in future outbreaks of COVID-19.


Assuntos
COVID-19 , Falência Renal Crônica , Minorias Étnicas e Raciais , Humanos , Falência Renal Crônica/terapia , Masculino , Diálise Renal , SARS-CoV-2
12.
Elife ; 102021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34581271

RESUMO

Social hierarchy formation is strongly evolutionarily conserved. Across species, rank within social hierarchy has large effects on health and behavior. To investigate the relationship between social rank and stress susceptibility, we exposed ranked male and female mice to social and non-social stressors and manipulated social hierarchy position. We found that rank predicts same sex social stress outcomes: dominance in males and females confers resilience while subordination confers susceptibility. Pre-existing rank does not predict non-social stress outcomes in females and weakly does so in males, but rank emerging under stress conditions reveals social interaction deficits in male and female subordinates. Both history of winning and rank of cage mates affect stress susceptibility in males: rising to the top rank through high mobility confers resilience and mice that lose dominance lose stress resilience, although gaining dominance over a subordinate animal does not confer resilience. Overall, we have demonstrated a relationship between social status and stress susceptibility, particularly when taking into account individual history of winning and the overall hierarchy landscape in male and female mice.


Assuntos
Hierarquia Social , Camundongos/psicologia , Estresse Psicológico , Adaptação Psicológica , Animais , Comportamento Animal , Feminino , Masculino , Camundongos Endogâmicos C57BL , Distância Psicológica , Predomínio Social
13.
Gen Psychiatr ; 34(3): e100448, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34222794

RESUMO

BACKGROUND: The WHO has classified depression as a disease of public concern. Police officers are a particular subpopulation group that is at an increased risk for mental health problems. This study examined the prevalence of depression, suicidality and associated risk factors among police officers in urban Tanzania. AIMS: The aim of this study was to examine the prevalence of depression, suicidality and associated risk factors among police officers in Tanzania. METHODS: A cross-sectional study was conducted between April 2019 and October 2020 among 550 participants in Dar es Salaam recruited using a multistage cluster sampling technique. The Patient Health Questionnaire-9 was used to screen for depression and suicidality. The Interpersonal Support Evaluation List-12 tool was used to measure perceived social support. Descriptive statistics were summarised using frequencies and percentages. Bivariate and multivariate analyses were used to establish associations between predictors of interest, depression and suicidality. RESULTS: There were 497 participants in the study. Of these, 76.6% (376 of 491) were men, and the median (IQR) age was 37.0 (17) years. Around 19.8% (96 of 486) of the police officers screened positive for depression and 15.4% (75 of 413) for suicidality. A significant proportion was either moderately (29 of 96, 30.2%) or severely depressed (8 of 75, 10.7 %). Of those who experienced suicidal thoughts, 10.7% (8 of 75) reported having daily suicidal thoughts. Perceiving low social support was associated with an increased risk of reporting depression (adjusted OR (aOR): 28.04, 95% CI: 8.42 to 93.37, p<0.001) and suicidality (aOR: 10.85, 95% CI: 3.56 to 33.08, p<0.001) as compared with those with high perceived social support. CONCLUSION: The magnitude of depression and suicidality among police officers in urban Tanzania is alarmingly high. The study findings indicate the need for routine screening for depression and suicidality among police officers and design appropriate mental health responsive services in this population.

14.
Vet Ophthalmol ; 24(4): 354-360, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33977630

RESUMO

OBJECTIVE: To demonstrate the existence of lymphatics in the canine anterior uvea using lymphatic-specific markers Lyve-1, Prox-1, and podoplanin, the endothelial cell marker CD31, and basement membrane matrix marker collagen IV. DESIGN: Prospective Study. ANIMALS: Eight normal globes from animals euthanized for unrelated health problems. PROCEDURES: Sagittally cut serial sections of six normal canine eyes were immunofluorescence double-stained with Lyve-1 and CD31 and single-stained with colorimetric Prox-1 and collagen IV. Three serial sections from 2 additional eyes were cut in the coronal plane at the level of the ciliary body and immunofluorescence double-stained with Lyve-1 and CD31 to map lymphatic channel distribution. Lymphatics from normal canine lymph nodes were used for validation of podoplanin. RESULTS: Four of 6 of the sagitally sectioned eyes had Lyve-1-positive lymphatic-like structures that were distinct from CD31-positive blood vessels in the iris base and ciliary body. Both of the coronally sectioned globes had Lyve-1-positive lymphatic-like structures in the ciliary body. The location of these structures was evaluated and found to be diffusely present circumferentially around the ciliary body. CONCLUSION AND CLINICAL RELEVANCE: These results support the existence of lymphatic channels in the anterior uveal tract of the canine eye. This could indicate the presence of a novel uveolymphatic outflow pathway, which may play a role in aqueous humor outflow. Future studies are needed to confirm the existence and elucidate the role of this proposed uveolymphatic outflow pathway and potentially develop novel treatment options for managing glaucoma.


Assuntos
Cães/anatomia & histologia , Vasos Linfáticos/anatomia & histologia , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Úvea/anatomia & histologia , Proteínas de Transporte Vesicular/metabolismo , Animais , Antígenos de Diferenciação/metabolismo , Corpo Ciliar/anatomia & histologia , Imunofluorescência/veterinária , Glicoproteínas de Membrana/metabolismo , Estudos Prospectivos
15.
Vet Pathol ; 58(5): 981-993, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33685296

RESUMO

Periostin is a matricellular protein important in regulating bone, tooth, and cardiac development. In pathologic conditions, periostin drives allergic and fibrotic inflammatory diseases and is also overexpressed in certain cancers. Periostin signaling in tumors has been shown to promote angiogenesis, metastasis, and cancer stem cell survival in rodent models, and its overexpression is associated with poor prognosis in human glioblastoma. However, the role of periostin in regulating tumorigenesis of canine cancers has not been evaluated. Given its role in bone development, we sought to evaluate mRNA and protein expression of periostin in canine osteosarcoma (OS) and assess its association with patient outcome. We validated an anti-human periostin antibody cross-reactive to canine periostin via western blot and immunohistochemistry and evaluated periostin expression in microarray data from 49 primary canine OS tumors and 8 normal bone samples. Periostin mRNA was upregulated greater than 40-fold in canine OS tumors compared to normal bone and was significantly correlated with periostin protein expression based on quantitative image analysis. However, neither periostin mRNA nor protein expression were associated with time to metastasis in this cohort. Gene Set Enrichment Analysis demonstrated significant enhancement of pro-tumorigenic pathways including canonical WNT signaling, epithelial-mesenchymal transition, and angiogenesis in periostin-high tumors, while periostin-low tumors demonstrated evidence of heightened antitumor immune responses. Overall, these data identify a novel antibody that can be used as a tool for evaluation of periostin expression in dogs and suggest that investigation of Wnt pathway-targeted drugs in periostin overexpressing canine OS may be a potential therapeutic target.


Assuntos
Neoplasias Ósseas , Doenças do Cão , Osteossarcoma , Animais , Biologia , Neoplasias Ósseas/veterinária , Cães , Transição Epitelial-Mesenquimal , Osteossarcoma/veterinária , Transdução de Sinais
16.
Eur J Trauma Emerg Surg ; 47(1): 145-151, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31471669

RESUMO

BACKGROUND: Venous thromboembolism (VTE) is a common morbidity in trauma patients. Standard VTE chemoprophylaxis is often inadequate. We hypothesized that weight-based dosing would result in appropriate prophylaxis more reliably than fixed dosing. METHODS: All patients admitted to a Level 1 trauma center over a 6-month period were included unless contra-indications for VTE prophylaxis existed. A prospective adjusted-dosing group was compared to a retrospective uniform-dosing group. The adjusted-dosing approach consisted of initial weight-based dosing of 0.5 mg/kg subcutaneously (subQ) every 12 h (q12h). Peak anti-factor Xa was measured. Patients outside of the prophylactic range had their dose adjusted by ± 10 mg. The uniform-dosing group received 30 mg subQ q12h, without adjustments. RESULTS: Eighty-four patients were included: 44 in the retrospective control cohort and 40 in the prospective experimental cohort. More patients were sub-prophylactically dosed in the uniform-dosing group relative to the adjusted-dosing group (25% vs 5%, p = 0.03). There was no difference in overall prophylactic range targeting, because the supra-prophylactically dosed patients in the adjusted-dosing group eliminated the effect (p = 0.173). However, after a single dose adjustment, zero patients were outside of prophylactic range (25% versus 0%, RR = infinite, p = 0.003). In the uniform-dosing group, anti-Xa level correlated with body surface area (BSA; R2 = 0.33, p < 0.0001) and weight (R2 = 0.26, p = 0.0005). Weight-based dosing both pre- and post-readjustment normalized the correlation of anti-Xa with BSA (R2 = 0.07, p = 0.1) and weight (R2 = 0.07, p = 0.1). CONCLUSIONS: Weight-based VTE prophylaxis with anti-Xa-based dose adjustment improves prophylactic range targeting relative to uniform dosing and eliminates variances secondary to BSA and weight in trauma patients.


Assuntos
Anticoagulantes/administração & dosagem , Peso Corporal , Enoxaparina/administração & dosagem , Inibidores do Fator Xa/administração & dosagem , Tromboembolia Venosa/prevenção & controle , Adulto , Testes de Coagulação Sanguínea , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Centros de Traumatologia
17.
J Immunol ; 205(11): 3083-3094, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33139490

RESUMO

Vertical transmission of the Zika virus (ZIKV) causes severe fetal defects, but the exact pathogenic mechanism is unclear. We identified up to a 10,480-fold higher expression of viral attachment factors AXL, GAS6, and PROS1 and a 3880-fold increase in ZIKV infectiousness/propagation in human term decidual stromal cells versus trophoblasts. Moreover, levels of viral attachment factors and ZIKV are significantly increased, whereas expression of innate immune response genes are significantly decreased, in human first trimester versus term decidual cells. ZIKV-infected decidual cell supernatants increased cytotrophoblasts infection up to 252-fold compared with directly infected cytotrophoblasts. Tizoxanide treatment efficiently inhibited Zika infection in both maternal and fetal cells. We conclude that ZIKV permissiveness, as well as innate immune responsiveness of human decidual cells, are gestational age dependent, and decidual cells augment ZIKV infection of primary human cytotrophoblast cultures, which are otherwise ZIKV resistant. Human decidual cells may act as reservoirs for trimester-dependent placental transmission of ZIKV, accounting for the higher Zika infection susceptibility and more severe fetal sequelae observed in early versus late pregnancy. Moreover, tizoxanide is a promising agent in preventing perinatal Zika transmission as well as other RNA viruses such as coronavirus.


Assuntos
Decídua , Idade Gestacional , Imunidade Inata , Transmissão Vertical de Doenças Infecciosas , Complicações Infecciosas na Gravidez , Infecção por Zika virus , Zika virus/imunologia , Animais , Chlorocebus aethiops , Decídua/imunologia , Decídua/patologia , Decídua/virologia , Feminino , Humanos , Gravidez , Complicações Infecciosas na Gravidez/imunologia , Complicações Infecciosas na Gravidez/patologia , Trofoblastos , Células Vero , Infecção por Zika virus/imunologia , Infecção por Zika virus/patologia , Infecção por Zika virus/transmissão
18.
Vet Comp Oncol ; 18(2): 169-175, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31365175

RESUMO

Canine cutaneous mast cell tumour (MCT) is the most common malignant skin tumour in dogs and can exhibit variable biologic behaviour. Dysregulated signalling through the receptor tyrosine kinase (RTK) KIT can promote cell proliferation and survival, and assessment of its dysregulation via detection of activating c-kit gene mutations or assessment of KIT protein localization is associated with multiple features of malignancy. The aim of the current study was to use a previously validated immunohistochemical (IHC) assay to directly measure phosphorylated KIT (pKIT) in order to investigate its association with other established prognostic markers, response to therapy, progression free interval (PFI) and overall survival time (OST) in dogs treated medically for measurable MCT. Tumour tissue from 74 dogs enrolled in a prospective study comparing toceranib and vinblastine for MCT treatment were evaluated for pKIT immunoreactivity. pKIT was variably expressed, with some degree of positivity observed in 49/74 cases (66%). pKIT immunoreactivity was significantly associated with aberrant KIT localization, high mitotic index and high histologic grade. On univariate analysis, pKIT immunoreactivity predicted shorter PFI and OST in the entire patient population as well as shorter PFI in the toceranib treated group, and was the sole predictive factor for OST upon multivariate analysis, while mitotic index was the sole independent predictive factor for PFI. These results demonstrate that IHC detection of pKIT correlates with several features of aggressive behaviour, and may confer information that is complementary to other prognostic factors. However, the role of pKIT in predicting outcome needs to be studied further before recommendations can be made for its routine use.


Assuntos
Doenças do Cão/tratamento farmacológico , Indóis/uso terapêutico , Sarcoma de Mastócitos/veterinária , Proteínas Proto-Oncogênicas c-kit/metabolismo , Pirróis/uso terapêutico , Neoplasias Cutâneas/veterinária , Vimblastina/uso terapêutico , Animais , Antineoplásicos/uso terapêutico , Doenças do Cão/patologia , Cães , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Sarcoma de Mastócitos/tratamento farmacológico , Fosforilação , Estudos Prospectivos , Proteínas Proto-Oncogênicas c-kit/genética , Neoplasias Cutâneas/tratamento farmacológico
19.
J Cell Biochem ; 120(8): 13783-13791, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30938854

RESUMO

The chimeric DnaJ-PKAc enzymeresulting from an approximately 400-kb deletion of chromosome 19 is a primary contributor to the oncogenic transformation that occurs in fibrolamellar hepatocellular carcinoma, also called fibrolamellar carcinoma (FLC). This oncogenic deletion juxtaposes exon 1 of the DNAJB1 heat shock protein gene with exon 2 of the PRKACA gene encoding the protein kinase A catalytic subunit, resulting in DnaJ-PKAc fusion under the transcriptional control of the DNAJB1 promoter. The expression of DnaJ-PKAc is approximately 10 times that of wild-type (wt) PKAc catalytic subunits, causing elevated and dysregulated kinase activity that contributes to oncogenic transformation. In normal cells, PKAc activity is regulated by a group of endogenous proteins, termed protein kinase inhibitors (PKI) that competitively inhibit PKAc and assist with the nuclear export of the enzyme. Currently, it is scarcely known whether interactions with PKI are perturbed in DnaJ-PKAc. In this report, we survey existing data sets to assess the expression levels of the various PKI isoforms that exist in humans to identify those that are candidates to encounter DnaJ-PKAc in both normal liver and FLC tumors. We then compare inhibition profiles of wtPKAc and DnaJ-PKAc against PKI and demonstrate that extensive structural homology in the active site clefts of the two enzymes confers similar kinase activities and inhibition by full-length PKI and PKI-derived peptides.


Assuntos
Subunidades Catalíticas da Proteína Quinase Dependente de AMP Cíclico , Proteínas de Choque Térmico HSP40 , Proteínas de Fusão Oncogênica , Peptídeos/química , Inibidores de Proteínas Quinases/química , Subunidades Catalíticas da Proteína Quinase Dependente de AMP Cíclico/antagonistas & inibidores , Subunidades Catalíticas da Proteína Quinase Dependente de AMP Cíclico/química , Subunidades Catalíticas da Proteína Quinase Dependente de AMP Cíclico/genética , Proteínas de Choque Térmico HSP40/antagonistas & inibidores , Proteínas de Choque Térmico HSP40/química , Proteínas de Choque Térmico HSP40/genética , Humanos , Isoenzimas/antagonistas & inibidores , Isoenzimas/genética , Proteínas de Fusão Oncogênica/antagonistas & inibidores , Proteínas de Fusão Oncogênica/química , Proteínas de Fusão Oncogênica/genética
20.
Integr Biol (Camb) ; 10(9): 502-515, 2018 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-30101242

RESUMO

In bacterial type 3 secretion, substrate proteins are actively transported from the bacterial cytoplasm into the host cell cytoplasm by a large membrane-embedded machinery called the injectisome. Injectisomes transport secretion substrates in response to specific environmental signals, but the molecular details by which the cytosolic secretion substrates are selected and transported through the type 3 secretion pathway remain unclear. Secretion activity and substrate selectivity are thought to be controlled by a sorting platform consisting of the proteins SctK, SctQ, SctL, and SctN, which together localize to the cytoplasmic side of membrane-embedded injectisomes. However, recent work revealed that sorting platform proteins additionally exhibit substantial cytosolic populations and that SctQ reversibly binds to and dissociates from the cytoplasmic side of membrane-embedded injectisomes. Based on these observations, we hypothesized that dynamic molecular turnover at the injectisome and cytosolic assembly among sorting platform proteins is a critical regulatory component of type 3 secretion. To determine whether sorting platform complexes exist in the cytosol, we measured the diffusive properties of the two central sorting platform proteins, SctQ and SctL, using live cell high-throughput 3D single-molecule tracking microscopy. Single-molecule trajectories, measured in wild-type and mutant Yersinia enterocolitica cells, reveal that both SctQ and SctL exist in several distinct diffusive states in the cytosol, indicating that these proteins form stable homo- and hetero-oligomeric complexes in their native environment. Our findings provide the first diffusive state-resolved insights into the dynamic regulatory network that interfaces stationary membrane-embedded injectisomes with the soluble cytosolic components of the type 3 secretion system.


Assuntos
Proteínas de Bactérias/metabolismo , Citosol/metabolismo , Imagem Individual de Molécula/instrumentação , Imagem Individual de Molécula/métodos , Yersinia enterocolitica/metabolismo , Algoritmos , Membrana Celular/metabolismo , Flagelos , Processamento de Imagem Assistida por Computador/métodos , Microscopia de Fluorescência , Método de Monte Carlo , Plasmídeos/metabolismo , Ligação Proteica , Domínios Proteicos , Transporte Proteico , Especificidade por Substrato , Virulência
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