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1.
Development ; 151(13)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38975828

RESUMO

Environment in general and social signals in particular could alter development. In Caenorhabditis elegans, male pheromones hasten development of hermaphrodite larvae. We show that this involves acceleration of growth and both somatic and germline development during the last larval stage (L4). Larvae exposed to male pheromones spend more time in L3 and less in the quiescent period between L3 and L4. This behavioral alteration improves provision in early L4, likely allowing for faster development. Larvae must be exposed to male pheromones in late L3 for behavioral and developmental effects to occur. Latter portions of other larval stages also contain periods of heightened sensitivity to environmental signals. Behavior during the early part of the larval stages is biased toward exploration, whereas later the emphasis shifts to food consumption. We argue that this organization allows assessment of the environment to identify the most suitable patch of resources, followed by acquisition of sufficient nutrition and salient information for the developmental events in the next larval stage. Evidence from other species indicates that such coordination of behavior and development may be a general feature of larval development.


Assuntos
Comportamento Animal , Caenorhabditis elegans , Larva , Feromônios , Animais , Larva/crescimento & desenvolvimento , Caenorhabditis elegans/crescimento & desenvolvimento , Masculino , Feromônios/metabolismo , Transtornos do Desenvolvimento Sexual
2.
Periodontol 2000 ; 95(1): 7-9, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39235922

RESUMO

Chronic inflammatory periodontal disease and its related condition, peri-implant disease, are highly prevalent globally and require accurate and speedy diagnosis. The focus of this volume dedicated to diagnostics is to cover modern enhancements in accuracy, simplicity and speed. An international assortment of experts has been tasked with reviewing defined areas of current best practice as well innovation in the field of periodontitis and peri-implantitis diagnostics. Periodontitis and peri-implantitis are irreversible, chronic, cumulative conditions propagated by bacteria and host factors, which involve soft and hard tissue changes, and these changes are measured in the diagnostic process. Clinically relevant modifications to the healthy state are detected using clinical, radiological and laboratory or point of care testing, and these testing approaches are critically reviewed at length in this state-of-the-art resume of periodontal diagnostics.


Assuntos
Peri-Implantite , Humanos , Implantes Dentários , Peri-Implantite/diagnóstico , Peri-Implantite/microbiologia , Periodontia/instrumentação , Periodontite/diagnóstico , Periodontite/microbiologia
3.
Periodontol 2000 ; 95(1): 156-175, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39004819

RESUMO

Periodontal diseases are highly prevalent chronic diseases, and severe periodontitis creates functional and esthetic problems and decreases self-esteem for a large percentage of the older population worldwide. In many cases of periodontitis, there is no distinct tell-tale pain that motivates a patient to seek treatment, rather the signs become clinically detectable late, and typically when the disease has progressed to a problematic level for the life of the dentition. Early periodontal screening and diagnostics tools will provide early recognition of periodontal diseases and facilitate timely management of the disease to reduce tooth loss. To this goal, gingival crevicular fluid is easily sampled, can be repeatedly and non-invasively collected, and can be tested for potential biomarkers. Moreover, the site specificity of periodontal diseases enhances the usefulness of gingival crevicular fluid sampled from specific sites as a biofluid for diagnosis and longitudinal monitoring of periodontal diseases. The present review aimed to provide up-to-date information on potential diagnostic biomarkers with utility that can be assayed from gingival crevicular fluid samples, focusing on what is new and useful and providing only general historic background textually and in a tabulated format.


Assuntos
Biomarcadores , Líquido do Sulco Gengival , Doenças Periodontais , Líquido do Sulco Gengival/química , Humanos , Biomarcadores/análise , Doenças Periodontais/diagnóstico
4.
Periodontol 2000 ; 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38641953

RESUMO

The aim of this narrative review is to relate the contribution of European researchers to the complex topic of the host immune system in periodontal disease, focusing on acquired immunity. Other chapters in this volume will address the genetics and autoantibody responses and other forms of immunity to periodontal disease. While the contribution of European authors is the focus, global literature is included in this descriptive narrative for contextual clarity, albeit many with European co-authors. The topic is relatively intense and is thus broken down into sections outlined below, tackled as descriptive narratives to enhance understanding. Any attempt at a systematic or scoping review was quickly abandoned given the descriptive nature and marked variation of approach in almost all publications. Even the most uniform area of this acquired periodontal immunology literature, antibody responses to putative pathogens in periodontal diseases, falls short of common structures and common primary outcome variables one would need and expect in clinical studies, where randomized controlled clinical trials (RCTs) abound. Addressing 'the host's role' in immunity immediately requires a discussion of host susceptibility, which necessitates consideration of genetic studies (covered elsewhere in the volume and superficially covered here).

5.
Periodontol 2000 ; 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38676371

RESUMO

Liquid biopsy is a noninvasive diagnostic technique used for monitoring cancer utilizing specific genetic biomarkers present in bodily fluids, such as blood, saliva, or urine. These analyses employ multiple biomolecular sources including circulating tumor DNA (ctDNA), circulating tumor cells (CTCs), and exosomes (that contain DNA fragments) to detect genetic biomarkers that can predict, disclose, and/or monitor cancers. Levels of these biomarkers can inform on the presence of cancer, its genetic characteristics, and its potential treatment response and also provide predictive genetic predisposition information for specific cancers including oral squamous cell carcinomas (OSCC). Liquid biopsies can aid cancer management as they offer real-time dynamic information on the response to say chemotherapy or radiotherapy and recurrence following surgical excision. Unlike traditional tissue biopsies, which are invasive with a degree of morbidity and require specific tumor location sampling, liquid biopsies are noninvasive and can be repeated frequently. For oral squamous cell carcinoma, on which this review focuses, liquid biopsy of blood or saliva can be valuable in predicting susceptibility, providing early detection, and monitoring the disease's progression and response to therapy. This review gives a general narrative overview of the technology, its current medical usage, and advantages and disadvantages compared with current techniques and discusses a range of current potential biomarkers for disclosing OSCC and predicting its risk. Oral squamous cell carcinoma is all too often detected in the late stages. In future, liquid biopsy may provide an effective screening process such that cancers including OSCC will be detected in the early stages rather than later when prognosis is poor and morbidity and debilitation are greater. In this screening process, periodontists and hygienists have a critical role in that they are adept in examining mucosa, they see patients with shared risk factors for periodontitis and OSCC, namely smoking and poor oral hygiene, and they see patients frequently such that OSCC examinations should be a routine part of the recall visit. With this additional screening manpower, oral medicine and oral surgery colleagues will detect OSCC earlier and this coupled with new techniques such as liquid biopsy may greatly decrease global morbidity in OSCC.

6.
Curr Opin Hematol ; 30(6): 194-202, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37548370

RESUMO

PURPOSE OF REVIEW: Packed red blood cells (PRBCs) are the most commonly transfused blood products. Preparation of PRBCs requires blood collection from donors, processing, and storage prior to transfusion to recipients. Stored red blood cells (RBCs) undergo structural and metabolic changes collectively known as the storage lesion. RBC extracellular vesicles (sREVs) are released in PRBC units during storage, and are transfused along with intact RBCs into recipients. For several decades, extracellular vesicles have been the focus of intense research, leading to the discovery of a wide variety of endogenous biological properties that may impact numerous physiologic and/or pathologic pathways. RECENT FINDINGS: This study reviews the characteristics of extracellular vesicles present in PRBC units and the impact of prestorage and pretransfusion processing, as well as storage conditions, on their generation. Importantly, we discuss recently described interactions of sREVs with coagulation pathways and related interplay with inflammatory pathways in vitro and in vivo using animal models. SUMMARY: Extracellular vesicles present in stored PRBC units are capable of activating coagulation pathways. However, it remains unclear whether this affects clinical outcomes in recipients of PRBC units. Further understanding of these pathways and their relationship to any adverse outcomes may yield novel strategies to mitigate complications of blood transfusion.


Assuntos
Preservação de Sangue , Vesículas Extracelulares , Animais , Humanos , Preservação de Sangue/efeitos adversos , Eritrócitos/metabolismo , Transfusão de Sangue , Coagulação Sanguínea
7.
Ann Oncol ; 34(10): 920-933, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37704166

RESUMO

BACKGROUND: Patients with advanced non-small-cell lung cancer (NSCLC) treated with immune checkpoint blockers (ICBs) ultimately progress either rapidly (primary resistance) or after durable benefit (secondary resistance). The cancer vaccine OSE2101 may invigorate antitumor-specific immune responses after ICB failure. The objective of ATALANTE-1 was to evaluate its efficacy and safety in these patients. PATIENTS AND METHODS: ATALANTE-1 was a two-step open-label study to evaluate the efficacy and safety of OSE2101 compared to standard-of-care (SoC) chemotherapy (CT). Patients with human leukocyte antigen (HLA)-A2-positive advanced NSCLC without actionable alterations, failing sequential or concurrent CT and ICB were randomized (2 : 1) to OSE2101 or SoC (docetaxel or pemetrexed). Primary endpoint was overall survival (OS). Interim OS futility analysis was planned as per Fleming design. In April 2020 at the time of interim analysis, a decision was taken to prematurely stop the accrual due to coronavirus disease 2019 (COVID-19). Final analysis was carried out in all patients and in the subgroup of patients with ICB secondary resistance defined as failure after ICB monotherapy second line ≥12 weeks. RESULTS: Two hundred and nineteen patients were randomized (139 OSE2101, 80 SoC); 118 had secondary resistance to sequential ICB. Overall, median OS non-significantly favored OSE2101 over SoC {hazard ratio (HR) [95% confidence interval (CI)] 0.86 [0.62-1.19], P = 0.36}. In the secondary resistance subgroup, OSE2101 significantly improved median OS versus SoC [11.1 versus 7.5 months; HR (95% CI) 0.59 (0.38-0.91), P = 0.017], and significantly improved post-progression survival (HR 0.46, P = 0.004), time to Eastern Cooperative Oncology Group (ECOG) performance status deterioration (HR 0.43, P = 0.006) and Quality of Life Questionnaire Core 30 (QLQ-C30) global health status compared to SoC (P = 0.045). Six-month disease control rates and progression-free survival were similar between groups. Grade ≥3 adverse effects occurred in 11.4% of patients with OSE2101 and 35.1% in SoC (P = 0.002). CONCLUSIONS: In HLA-A2-positive patients with advanced NSCLC and secondary resistance to immunotherapy, OSE2101 increased survival with better safety compared to CT. Further evaluation in this population is warranted.


Assuntos
COVID-19 , Vacinas Anticâncer , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Vacinas Anticâncer/efeitos adversos , Antígeno HLA-A2/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/etiologia , Qualidade de Vida , Resultado do Tratamento , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , COVID-19/etiologia , Imunoterapia
8.
Blood ; 138(3): 259-272, 2021 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-33827130

RESUMO

Acetaminophen (APAP)-induced liver injury is associated with activation of coagulation and fibrinolysis. In mice, both tissue factor-dependent thrombin generation and plasmin activity have been shown to promote liver injury after APAP overdose. However, the contribution of the contact and intrinsic coagulation pathways has not been investigated in this model. Mice deficient in individual factors of the contact (factor XII [FXII] and prekallikrein) or intrinsic coagulation (FXI) pathway were administered a hepatotoxic dose of 400 mg/kg of APAP. Neither FXII, FXI, nor prekallikrein deficiency mitigated coagulation activation or hepatocellular injury. Interestingly, despite the lack of significant changes to APAP-induced coagulation activation, markers of liver injury and inflammation were significantly reduced in APAP-challenged high-molecular-weight kininogen-deficient (HK-/-) mice. Protective effects of HK deficiency were not reproduced by inhibition of bradykinin-mediated signaling, whereas reconstitution of circulating levels of HK in HK-/- mice restored hepatotoxicity. Fibrinolysis activation was observed in mice after APAP administration. Western blotting, enzyme-linked immunosorbent assay, and mass spectrometry analysis showed that plasmin efficiently cleaves HK into multiple fragments in buffer or plasma. Importantly, plasminogen deficiency attenuated APAP-induced liver injury and prevented HK cleavage in the injured liver. Finally, enhanced plasmin generation and HK cleavage, in the absence of contact pathway activation, were observed in plasma of patients with acute liver failure due to APAP overdose. In summary, extrinsic but not intrinsic pathway activation drives the thromboinflammatory pathology associated with APAP-induced liver injury in mice. Furthermore, plasmin-mediated cleavage of HK contributes to hepatotoxicity in APAP-challenged mice independently of thrombin generation or bradykinin signaling.


Assuntos
Acetaminofen/efeitos adversos , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Fibrinolisina/metabolismo , Fibrinólise/efeitos dos fármacos , Cininogênios/metabolismo , Proteólise/efeitos dos fármacos , Acetaminofen/farmacologia , Animais , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/patologia , Fator XII/genética , Fator XII/metabolismo , Feminino , Fibrinolisina/genética , Humanos , Cininogênios/genética , Masculino , Camundongos , Camundongos Knockout , Pré-Calicreína/genética , Pré-Calicreína/metabolismo
9.
Ear Hear ; 44(4): 740-750, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36631948

RESUMO

OBJECTIVES: This study compared the measurement of the acoustic stapedius reflex threshold (ART) obtained using a traditional method with that obtained using an automated adaptive wideband (AAW) method. Participants included three groups of adults with normal hearing (NH), mild sensorineural hearing loss (SNHL), or moderate SNHL. The purpose of the study was to compare ARTs for the three groups and to determine which method had the best performance in detecting SNHL. DESIGN: Ipsilateral and contralateral ARTs were obtained using 0.5, 1, and 2 kHz tonal activators, and broadband noise (BBN) activators on a traditional admittance system (Clinical) at tympanometric peak pressures (TPP) and on an experimental wideband system using an AAW method at both ambient pressure and TPP. ART data previously reported for 39 NH adults with a mean age of 47.7 years were compared with data for 25 participants with mild SNHL with a mean age of 63.8 years, and 20 participants with moderate SNHL with a mean age of 65.7 years. Differences in ARTs between the normal-hearing and SNHL groups for the three methods were examined using a General Linear Model Repeated-Measures test. A receiver operating characteristic curve (ROC) analysis was also used to determine the ability of an ART test to detect SNHL. RESULTS: For the 0.5 kHz activator condition, there were no significant group mean differences in ART between NH and SNHL groups for either ipsilateral or contralateral activator presentation modes for the Clinical or AAW methods. There were significant group mean differences for the 1 and 2 kHz tonal activators and BBN activator for both ipsilateral and contralateral modes with greater differences in ART between groups for the AAW method than the Clinical method. In these conditions, the mean ART was lower for the AAW tests relative to the Clinical test. The greatest difference between groups was for the ipsilateral AAW tests for the comparison of NH with moderate SNHL for the BBN activator. This difference was approximately 20 dB for the AAW tests and 8 dB for the Clinical test. The ROC analysis showed that the area under the ROC curve (AUC) increased with the frequency of the activator stimulus and with the degree of hearing loss and was maximal for the BBN activator for both the AAW and Clinical methods for both ipsilateral and contralateral presentations. CONCLUSIONS: For ipsilateral and contralateral ART tests for activator frequencies above 0.5 kHz and BBN, listeners with SNHL generally had elevated ARTs compared with those with NH. The AAW method resulted in greater differences between SNHL groups and NH than the Clinical method. The AUC for detecting SNHL also increased with activator frequency and degree of hearing loss and was greatest for the BBN activator for the AAW method in both the ambient and TPP conditions. The results are encouraging for the use of an AAW ART method for the assessment of individuals with SNHL.


Assuntos
Surdez , Perda Auditiva Neurossensorial , Perda Auditiva , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Estapédio , Limiar Auditivo , Perda Auditiva Neurossensorial/diagnóstico , Testes de Impedância Acústica , Acústica , Audição , Reflexo , Reflexo Acústico
10.
Dev Biol ; 475: 54-64, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33636188

RESUMO

Understanding temporal regulation of development remains an important challenge. Whereas average, species-typical timing of many developmental processes has been established, less is known about inter-individual variability and correlations in timing of specific events. We addressed these questions in the context of postembryonic development in Caenorhabditis elegans. Based on patterns of locomotor activity of freely moving animals, we inferred durations of four larval stages (L1-L4) in over 100 individuals. Analysis of these data supports several conclusions. Individuals have consistently faster or slower rates of development because durations of L1 through L3 stages are positively correlated. The last larval stage, the L4, is less variable than the earlier stages and its duration is largely independent of the rate of early larval development, implying existence of two distinct larval epochs. We describe characteristic patterns of variation and correlation, as well as the fact that stage durations tend to scale relative to total developmental time. This scaling relationship suggests that each larval stage is not limited by an absolute duration, but is instead terminated when a subset of events that must occur prior to adulthood have been completed. The approach described here offers a scalable platform that will facilitate the study of temporal regulation of postembryonic development.


Assuntos
Caenorhabditis elegans/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento/genética , Larva/metabolismo , Animais , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Expressão Gênica/genética , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Larva/crescimento & desenvolvimento , Locomoção/genética , Locomoção/fisiologia , Análise Espaço-Temporal
11.
Blood ; 135(10): 755-765, 2020 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-31971571

RESUMO

Storage lesion-induced, red cell-derived microvesicles (RBC-MVs) propagate coagulation by supporting the assembly of the prothrombinase complex. It has also been reported that RBC-MVs initiate coagulation via the intrinsic pathway. To elucidate the mechanism(s) of RBC-MV-induced coagulation activation, the ability of storage lesion-induced RBC-MVs to activate each zymogen of the intrinsic pathway was assessed in a buffer system. Simultaneously, the thrombin generation (TG) assay was used to assess their ability to initiate coagulation in plasma. RBC-MVs directly activated factor XII (FXII) or prekallikrein, but not FXI or FIX. RBC-MVs initiated TG in normal pooled plasma and in FXII- or FXI-deficient plasma, but not in FIX-deficient plasma, suggesting an alternate pathway that bypasses both FXII and FXI. Interestingly, RBC-MVs generated FIXa in a prekallikrein-dependent manner. Similarly, purified kallikrein activated FIX in buffer and initiated TG in normal pooled plasma, as well as FXII- or FXI-deficient plasma, but not FIX-deficient plasma. Dual inhibition of FXIIa by corn trypsin inhibitor and kallikrein by soybean trypsin inhibitor was necessary for abolishing RBC-MV-induced TG in normal pooled plasma, whereas kallikrein inhibition alone was sufficient to abolish TG in FXII- or FXI-deficient plasma. Heating RBC-MVs at 60°C for 15 minutes or pretreatment with trypsin abolished TG, suggesting the presence of MV-associated proteins that are essential for contact activation. In summary, RBC-MVs activate both FXII and prekallikrein, leading to FIX activation by 2 independent pathways: the classic FXIIa-FXI-FIX pathway and direct kallikrein activation of FIX. These data suggest novel mechanisms by which RBC transfusion mediates inflammatory and/or thrombotic outcomes.


Assuntos
Coagulação Sanguínea/fisiologia , Micropartículas Derivadas de Células/fisiologia , Eritrócitos/ultraestrutura , Fator IX/metabolismo , Testes de Coagulação Sanguínea , Agregação Celular/fisiologia , Comunicação Celular/fisiologia , Humanos , Transdução de Sinais/fisiologia
12.
Blood ; 133(20): 2186-2197, 2019 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-30898858

RESUMO

Reactive and clonal neutrophil expansion has been associated with thrombosis, suggesting that neutrophils play a role in this process. However, although there is no doubt that activated monocytes trigger coagulation in a tissue factor-dependent manner, it remains uncertain whether stimulated neutrophils can also directly activate coagulation. After more than a decade of debate, it is now largely accepted that normal human neutrophils do not synthetize tissue factor, the initiator of the extrinsic pathway of coagulation. However, neutrophils may passively acquire tissue factor from monocytes. Recently, the contact system, which initiates coagulation via the intrinsic pathway, has been implicated in the pathogenesis of thrombosis. After the recent description of neutrophil extracellular trap (NET) release by activated neutrophils, some animal models of thrombosis have demonstrated that coagulation may be enhanced by direct NET-dependent activation of the contact system. However, there is currently no consensus on how to assess or quantify NETosis in vivo, and other experimental animal models have failed to demonstrate a role for neutrophils in thrombogenesis. Nevertheless, it is likely that NETs can serve to localize other circulating coagulation components and can also promote vessel occlusion independent of fibrin formation. This article provides a critical appraisal of the possible roles of neutrophils in thrombosis and highlights some existing knowledge gaps regarding the procoagulant activities of neutrophil-derived extracellular chromatin and its molecular components. A better understanding of these mechanisms could guide future approaches to prevent and/or treat thrombosis.


Assuntos
Coagulação Sanguínea , Cromatina/metabolismo , Armadilhas Extracelulares/metabolismo , Neutrófilos/metabolismo , Trombose/metabolismo , Animais , Apoptose , Humanos , Neutrófilos/citologia , Trombose/sangue
13.
Blood ; 133(23): 2529-2541, 2019 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-30952675

RESUMO

Sickle cell disease (SCD) is associated with chronic activation of coagulation and an increased risk of venous thromboembolism. Erythrocyte sickling, the primary pathologic event in SCD, results in dramatic morphological changes in red blood cells (RBCs) because of polymerization of the abnormal hemoglobin. We used a mouse model of SCD and blood samples from sickle patients to determine if these changes affect the structure, properties, and dynamics of sickle clot formation. Sickling of RBCs and a significant increase in fibrin deposition were observed in venous thrombi formed in sickle mice. During ex vivo clot contraction, the number of RBCs extruded from sickle whole blood clots was significantly reduced compared with the number released from sickle cell trait and nonsickle clots in both mice and humans. Entrapment of sickled RBCs was largely factor XIIIa-independent and entirely mediated by the platelet-free cellular fraction of sickle blood. Inhibition of phosphatidylserine, but not administration of antisickling compounds, increased the number of RBCs released from sickle clots. Interestingly, whole blood, but not plasma clots from SCD patients, was more resistant to fibrinolysis, indicating that the cellular fraction of blood mediates resistance to tissue plasminogen activator. Sickle trait whole blood clots demonstrated an intermediate phenotype in response to tissue plasminogen activator. RBC exchange in SCD patients had a long-lasting effect on normalizing whole blood clot contraction. Furthermore, RBC exchange transiently reversed resistance of whole blood sickle clots to fibrinolysis, in part by decreasing platelet-derived PAI-1. These properties of sickle clots may explain the increased risk of venous thromboembolism observed in SCD.


Assuntos
Anemia Falciforme/complicações , Anemia Falciforme/patologia , Eritrócitos Anormais/patologia , Trombose/patologia , Trombose Venosa/patologia , Anemia Falciforme/sangue , Animais , Eritrócitos/patologia , Humanos , Camundongos , Trombose/sangue , Trombose Venosa/sangue , Trombose Venosa/etiologia
14.
Ear Hear ; 42(3): 547-557, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33156125

RESUMO

OBJECTIVE: Wideband absorbance and absorbed power were evaluated in a group of subjects with surgically confirmed otosclerosis (Oto group), mean age 51.6 years. This is the first use of absorbed power in the assessment of middle ear disorders. Results were compared with control data from two groups of adults, one with normal hearing (NH group) mean age of 31 years, and one that was age- and sex-matched with the Oto group and had sensorineural hearing loss (SNHL group). The goal was to assess group differences using absorbance and absorbed power, to determine test performance in detecting otosclerosis, and to evaluate preoperative and postoperative test results. DESIGN: Audiometric and wideband tests were performed over frequencies up to 8 kHz. The three groups were compared on wideband tests using analysis of variance to assess group mean differences. Receiver operating characteristic (ROC) curve analysis was also used to assess test accuracy at classifying ears as belonging to the Oto or control groups using the area under the ROC curve (AUC). A longitudinal design was used to compare preoperative and postoperative results at 3 and 6 months. RESULTS: There were significant mean differences in the wideband parameters between the Oto and control groups with generally lower absorbance and absorbed power for the Oto group at ambient and tympanometric peak pressure (TPP) depending on frequency. The SNHL group had more significant differences with the Oto group than did the NH group in the high frequencies for absorbed power at ambient pressure and tympanometric absorbed power at TPP, as well as for the tympanometric tails. The greatest accuracy for classifying ears as being in the Oto group or a control group was for absorbed power at ambient pressure at 0.71 kHz with an AUC of 0.81 comparing the Oto and NH groups. The greatest accuracy for an absorbance measure was for the comparison between the Oto and NH groups for the peak-to-negative tail condition with an AUC of 0.78. In contrast, the accuracy for classifying ears into the control or Oto groups for static acoustic admittance at 226 Hz was near chance performance, which is consistent with previous findings. There were significant mean differences between preoperative and postoperative tests for absorbance and absorbed power. CONCLUSIONS: Consistent with previous studies, wideband absorbance showed better sensitivity for detecting the effects of otosclerosis on middle ear function than static acoustic admittance at 226 Hz. This study showed that wideband absorbed power is similarly sensitive and may perform even better in some instances than absorbance at classifying ears as having otosclerosis. The use of a group that was age- and sex-matched to the Oto group generally resulted in greater differences between groups in the high frequencies for absorbed power, suggesting that age-related norms in adults may be useful for the wideband clinical applications. Absorbance and absorbed power appear useful for monitoring changes in middle ear function following surgery for otosclerosis.


Assuntos
Perda Auditiva Neurossensorial , Otosclerose , Testes de Impedância Acústica , Adulto , Audiometria , Orelha Média , Humanos , Pessoa de Meia-Idade
15.
Haematologica ; 105(1): 218-225, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31048354

RESUMO

Pancreatic cancer is associated with a high incidence of venous thromboembolism. Neutrophils have been shown to contribute to thrombosis in part by releasing neutrophil extracellular traps (NET). A recent study showed that increased plasma levels of the NET biomarker, citrullinated histone H3 (H3Cit), are associated with venous thromboembolism in patients with pancreatic and lung cancer but not in those with other types of cancer, including breast cancer. In this study, we examined the contribution of neutrophils and NET to venous thrombosis in nude mice bearing human pancreatic tumors. We found that tumor-bearing mice had increased circulating neutrophil counts and levels of granulocyte-colony stimulating factor, neutrophil elastase, H3Cit and cell-free DNA compared with controls. In addition, thrombi from tumor-bearing mice contained increased levels of the neutrophil marker Ly6G, as well as higher levels of H3Cit and cell-free DNA. Thrombi from tumor-bearing mice also had denser fibrin with thinner fibers consistent with increased thrombin generation. Importantly, either neutrophil depletion or administration of DNase I reduced the thrombus size in tumor-bearing but not in control mice. Our results, together with clinical data, suggest that neutrophils and NET contribute to venous thrombosis in patients with pancreatic cancer.


Assuntos
Armadilhas Extracelulares , Neoplasias Pancreáticas , Trombose Venosa , Animais , Humanos , Camundongos , Camundongos Nus , Neutrófilos , Trombose Venosa/etiologia
16.
Blood ; 129(8): 1021-1029, 2017 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-27919911

RESUMO

NETosis is a physiologic process in which neutrophils release their nuclear material in the form of neutrophil extracellular traps (NETs). NETs have been reported to directly promote thrombosis in animal models. Although the effects of purified NET components including DNA, histone proteins, and neutrophil enzymes on coagulation have been characterized, the mechanism by which intact NETs promote thrombosis is largely unknown. In this study, human neutrophils were stimulated to produce NETs in platelet-free plasma (PFP) or in buffer using phorbol myristate actetate or calcium ionophore. DNA and histone proteins were also separately purified from normal human neutrophils and used to reconstitute chromatin using a salt-gradient dialysis method. Neutrophil stimulation resulted in robust NET release. In recalcified PFP, purified DNA triggered contact-dependent thrombin generation (TG) and amplified TG initiated by low concentrations of tissue factor. Similarly, in a buffer milieu, DNA initiated the contact pathway and amplified thrombin-dependent factor XI activation. Recombinant human histones H3 and H4 triggered TG in recalcified human plasma in a platelet-dependent manner. In contrast, neither intact NETs, reconstituted chromatin, individual nucleosome particles, nor octameric core histones reproduced any of these procoagulant effects. We conclude that unlike DNA or individual histone proteins, human intact NETs do not directly initiate or amplify coagulation in vitro. This difference is likely explained by the complex histone-histone and histone-DNA interactions within the nucleosome unit and higher-order supercoiled chromatin leading to neutralization of the negative charges on polyanionic DNA and modification of the binding properties of individual histone proteins.


Assuntos
Coagulação Sanguínea , DNA/metabolismo , Armadilhas Extracelulares/metabolismo , Histonas/metabolismo , Neutrófilos/metabolismo , Separação Celular , DNA/isolamento & purificação , Histonas/isolamento & purificação , Humanos , Neutrófilos/citologia , Nucleossomos/metabolismo
17.
Microb Pathog ; 131: 53-64, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30940608

RESUMO

Polymorphonuclear neutrophils (PMNs) are indispensable in fighting infectious microbes by adopting various antimicrobial strategies including phagocytosis and neutrophil extracellular traps (NETs). Although the role and importance of PMNs in periodontal disease are well established, the specific molecular mechanisms involved in NET formation are yet to be characterized. In the present study, we sought to determine the role of periodontal pathogen on NET formation by utilizing Fusobacterium nucleatum. Our data demonstrates that F. nucleatum activates neutrophils and induces robust NETosis in a time-dependent manner via the upregulation of the Nucleotide oligomerization domain 1 (NOD1) and NOD2 receptors. Furthermore, CRISPR/Cas9 knockout of HL-60 cells and the use of ligands/inhibitors confirmed the involvement of NOD1 and NOD2 receptors in F. nucleatum-mediated NET formation. When treated with NOD1 and NOD2 inhibitors, we observed a significant downregulation of peptidylarginine deiminase 4 (PAD4) activity. In addition, neutrophils showed a significant increase and decrease of myeloperoxidase (MPO) and neutrophil elastase (NE) when treated with NOD1/NOD2 ligands and inhibitors, respectively. Taken together, CRISPR/Cas9 knockout of NOD1/NOD2 HL-60 cells and inhibitors of NOD signaling confirmed the role of NLRs in F. nucleatum-mediated NETosis. Our data demonstrates an important pathway linking NOD1 and NOD2 to NETosis by F. nucleatum, a prominent microbe in periodontal biofilms. This is the first study to elucidate the role of NOD-like receptors in NETosis and their downstream signaling network.


Assuntos
Fusobacterium nucleatum/patogenicidade , Neutrófilos/imunologia , Neutrófilos/metabolismo , Proteína Adaptadora de Sinalização NOD1/metabolismo , Proteína Adaptadora de Sinalização NOD2/metabolismo , Periodontite/metabolismo , Biofilmes , Sistemas CRISPR-Cas/genética , Regulação para Baixo , Células HL-60 , Histonas/metabolismo , Humanos , Elastase de Leucócito/metabolismo , Periodontite/microbiologia , Peroxidase/metabolismo , Fagocitose , Proteína-Arginina Desiminase do Tipo 4 , Desiminases de Arginina em Proteínas/metabolismo , Transdução de Sinais
18.
J Clin Periodontol ; 46(8): 819-829, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31131910

RESUMO

AIM: The purpose of this study was to determine inflammatory and epigenetic features following induction of oral and gut dysbiosis in experimental periodontitis in order to examine the interplay between oral and systemic infection. MATERIALS AND METHODS: Periodontitis was induced in 6- to 8-week-old C57BL/6 mice by (a) Ligature placement (Lig group) (oral challenge); (b) P. gingivalis gavage (Pg group) (systemic challenge); and (c) the combination of the two models oral and systemic challenge (Pg + Lig). The duration of the experiment was 60 days, and the animals were then sacrificed for analyses. Alveolar bone loss was assessed, and a multiplex immunoassay was performed. Maxillae and gut tissues were immunostained for DNMT3b (de novo methylation marker), B and T lymphocyte attenuator (BTLA) and IL-18R1 (inflammation markers). RESULTS: Pg and Pg + Lig groups exhibited higher bone loss when compared to Sham. BAFF, VEGF, RANKL, RANTES and IP-10 were significantly higher with Pg gavage. Likewise, DNMT3b was overexpressed in both gut and maxilla after the Pg administration. The same pattern was observed for BTLA and IL-18R1 in gut tissues. CONCLUSIONS: The systemic microbial challenge either alone or in combination with local challenge leads to distinct patterns of inflammatory and epigenetic features when compared to simply locally induced experimental periodontitis.


Assuntos
Perda do Osso Alveolar , Periodontite , Animais , Modelos Animais de Doenças , Epigênese Genética , Camundongos , Camundongos Endogâmicos C57BL , Porphyromonas gingivalis
19.
J Environ Sci Health B ; 54(10): 803-809, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31264502

RESUMO

The aim of this study was to evaluate the effect of time of the day and their associated climatic conditions on spray deposition of two 2,4-D formulations, as well as the influence on weed control. The experiment was installed in the field in complete randomized design. Treatments were arranged in factorial design 8 × 2, with 20 repetitions. First factor corresponded to different application time (1:00, 4:00, 7:00, 10:00, 13:00, 16:00, 19:00, and 22:00) with their respective climatic conditions. The second factor consisted of two formulations of 2,4-D applied at 776 g a.e. ha-1 (2,4-D amine and 2,4-D choline salt with Colex-D™ Technology) + glyphosate (816 g a.e. ha-1). There was more spray deposition when 2,4-D choline formulation was used, and such differences were more evident for applications performed under adverse climatic conditions. More spray deposition was found in applications performed at times of day with more favorable temperature and humidity of the air conditions. Only the initial control of the evaluated species was affected by the time of application.


Assuntos
Ácido 2,4-Diclorofenoxiacético , Herbicidas , Plantas Daninhas , Controle de Plantas Daninhas/métodos , Ácido 2,4-Diclorofenoxiacético/administração & dosagem , Bidens , Brasil , Cenchrus , Commelina , Glicina/administração & dosagem , Glicina/análogos & derivados , Herbicidas/administração & dosagem , Umidade , Distribuição Aleatória , Temperatura , Tempo (Meteorologia) , Glifosato
20.
Kidney Blood Press Res ; 43(6): 1765-1771, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30504701

RESUMO

BACKGROUND/AIMS: Elderly patients with normal systemic arterial blood pressure associated with femoral carotid pulse velocity (cf-PWV) less than 7.6 m/s and without associated comorbidities are considered to have good vascular health. The aim of the current study was to verify the probability that elderly patients with good vascular health have at least one blood pressure measurement above the different thresholds for systolic blood pressure (120, 130 and 140 mmHg) during two years of follow-up. METHODS: We selected 72 normotensive patients (< 140/90 mmHg) without comorbidities and divided them into group A, with cf-PWV < 7.6 m/s (n = 27; 65 ± 4 years), and group B, with cf-PWV ≥ 7.6 m/s (n = 45; 66± 8 years). These patients were followed for two years and were observed in 3 outpatient visits (0, 12 and 24 months). At each visit, the brachial pressures were indirectly measured in triplicate, and applanation tonometry was performed. RESULTS: When group A and group B were compared, the odds ratio (OR) of having a systolic pressure measurement ≥ 140 mmHg in two years of follow-up was 0.22 (P < 0.0001); ≥ 130 mmHg, the OR was 0.49 (P < 0.0007), and ≥ 120 mmHg, the OR was 0.54 (P < 0.001). Group A and group B showed increased values of cf-PWV during the two years of follow-up (P < 0.05). Changes in the average systolic brachial pressure were not significant during the two years in groups A or B. CONCLUSION: Vascular health in elderly individuals seems to protect against occasional elevations in systemic arterial pressure.


Assuntos
Pressão Arterial/fisiologia , Análise de Onda de Pulso/estatística & dados numéricos , Idoso , Feminino , Seguimentos , Humanos , Hipertensão/diagnóstico , Hipertensão/fisiopatologia , Masculino , Probabilidade
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