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Memory B cell reserves can generate protective antibodies against repeated SARS-CoV-2 infections, but with unknown reach from original infection to antigenically drifted variants. We charted memory B cell receptor-encoded antibodies from 19 COVID-19 convalescent subjects against SARS-CoV-2 spike (S) and found seven major antibody competition groups against epitopes recurrently targeted across individuals. Inclusion of published and newly determined structures of antibody-S complexes identified corresponding epitopic regions. Group assignment correlated with cross-CoV-reactivity breadth, neutralization potency, and convergent antibody signatures. Although emerging SARS-CoV-2 variants of concern escaped binding by many members of the groups associated with the most potent neutralizing activity, some antibodies in each of those groups retained affinity-suggesting that otherwise redundant components of a primary immune response are important for durable protection from evolving pathogens. Our results furnish a global atlas of S-specific memory B cell repertoires and illustrate properties driving viral escape and conferring robustness against emerging variants.
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Antibodies are key immune effectors that confer protection against pathogenic threats. The nature and longevity of the antibody response to SARS-CoV-2 infection are not well defined. We charted longitudinal antibody responses to SARS-CoV-2 in 92 subjects after symptomatic COVID-19. Antibody responses to SARS-CoV-2 are unimodally distributed over a broad range, with symptom severity correlating directly with virus-specific antibody magnitude. Seventy-six subjects followed longitudinally to â¼100 days demonstrated marked heterogeneity in antibody duration dynamics. Virus-specific IgG decayed substantially in most individuals, whereas a distinct subset had stable or increasing antibody levels in the same time frame despite similar initial antibody magnitudes. These individuals with increasing responses recovered rapidly from symptomatic COVID-19 disease, harbored increased somatic mutations in virus-specific memory B cell antibody genes, and had persistent higher frequencies of previously activated CD4+ T cells. These findings illuminate an efficient immune phenotype that connects symptom clearance speed to differential antibody durability dynamics.
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Anticorpos Antivirais/imunologia , Formação de Anticorpos , Linfócitos T CD4-Positivos/imunologia , COVID-19 , Imunoglobulina G/imunologia , Ativação Linfocitária , Mutação , COVID-19/genética , COVID-19/imunologia , Humanos , SARS-CoV-2/genética , SARS-CoV-2/imunologiaRESUMO
INTRODUCTION: Immune checkpoint inhibitors (ICIs) have been widely used in the contemporary anticancer armamentarium. However, new side effects due to these agents have continued to emerge. CASE REPORT: We describe herein a 71-year-old patient who received nivolumab as adjuvant therapy for malignant melanoma of the skin. He developed eosinophilia starting at 4 weeks of therapy. Eosinophilia increased progressively during the first six nivolumab cycles, then stabilized. Cycle-dependent increments were observed. Subsequently, the patient experienced well-known side effects of ICIs such as grade 1 diarrhea, arthralgias, and erythematous papular rash. MANAGEMENT AND OUTCOME: Nivolumab was continued, and absolute eosinophil counts were monitored. Prednisone 10 mg PO daily was required for moderate gastroenteritis, dermatitis, and arthritis, which all subsequently improved. Eosinophil levels gradually downtrended after starting prednisone. Causality assessment between nivolumab and eosinophilia via adverse drug reaction (ADR) probability scale revealed a score of 9. DISCUSSION: Physicians and pharmacists need to be aware of this important side effect of ICI therapy. Eosinophilia in the context of ICI use has been previously reported in clinical trials. Our case is unique as eosinophilia was cumulative, showed increments every 8 weeks, and exhibited a trend toward cycle dependency. Extensive and expensive workup does not appear warranted, and simple monitoring of complete blood count is appropriate in most patients. Further studies are necessary to assess the true incidence, pattern, and severity of eosinophilia related to ICIs as well as its association with clinical outcomes.
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Antineoplásicos Imunológicos , Eosinofilia , Melanoma , Masculino , Humanos , Idoso , Nivolumabe/efeitos adversos , Prednisona/uso terapêutico , Antineoplásicos Imunológicos/efeitos adversos , Melanoma/tratamento farmacológico , Melanoma/patologia , Eosinofilia/induzido quimicamente , Eosinofilia/complicações , Eosinofilia/tratamento farmacológico , Melanoma Maligno CutâneoRESUMO
INTRODUCTION: Oxaliplatin has become the mainstay of treatment for many cancers, but its use can be accompanied by unusual side effects. CASE REPORT: We describe herein a 74-year-old patient with pancreatic cancer who developed severe motor weakness affecting lower extremities after starting treatment with oxaliplatin on three separate occasions. Our patient also experienced slurred speech, with decreased ability to phonate and word-finding difficulty. Brain imaging studies did not suggest recent brain ischemia, and the symptoms resolved within 15-20â h. MANAGEMENT AND OUTCOME: Oxaliplatin had to be discontinued due to suboptimal tolerance and a short-lived clinical response. After discontinuation of oxaliplatin, she did not experience any more similar symptoms. A score of 9 on the Naranjo nomogram supported a definite causality relationship between oxaliplatin and the observed neurologic toxicity. DISCUSSION: Rare reports of stroke-like events have previously been described with oxaliplatin. While the exact mechanism of these phenomena is not known, alterations in neuronal sodium channels might be involved. Clinicians, pharmacists, and patients need to be aware of these rare but important side effects of oxaliplatin. Nonetheless, work-up for a cerebrovascular accident is still warranted as hypercoagulability related to malignancy can also predispose the patients to strokes.
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Antineoplásicos , Neoplasias Pancreáticas , Acidente Vascular Cerebral , Feminino , Humanos , Idoso , Oxaliplatina/efeitos adversos , Antineoplásicos/efeitos adversos , Neoplasias Pancreáticas/tratamento farmacológico , Acidente Vascular Cerebral/induzido quimicamente , Acidente Vascular Cerebral/tratamento farmacológicoRESUMO
OBJECTIVE: This paper reviews comprehensively the most relevant data on single-agent and combination therapies for advanced colorectal cancer with inherited and acquired microsatellite instability (MSI). DATA SOURCES: We performed a systematic search on PubMed and MEDLINE articles published from inception to December 2022. We have also searched independent websites including U.S. Food and Drug Administration and ClinicalTrials.gov. DATA SUMMARY: Performing microsatellite stability testing, tumor mutational burden (TMB), and germline mutation analysis could identify patients with metastatic colorectal cancer that benefit from immune checkpoint inhibitor (ICI) therapy. Single-agent pembrolizumab has proven superiority over traditional chemotherapy in these patients. The nivolumab-ipilimumab is the only combination ICI therapy approved in this space. Recently, the anti-PD-1 antibody dostarlimab was granted Food and Drug Administration approval in refractory tissue-agnostic advanced solid cancers with deficient mismatch repair (dMMR). ICIs are also being studied in the adjuvant/neoadjuvant setting in colon cancer patients with dMMR. Newer agents are being scrutinized in this space as well. More solid data on biomarkers predicting responses in patients with MSI-high or TMB-H to various therapies are needed. Given its both clinical and financial toxicity, it is imperative to determine the optimal duration of ICI therapy in individual patients. CONCLUSIONS: Overall, the outlook in advanced colorectal cancer patients with MSI appears optimistic as new and efficacious ICI drugs and combinations are being added to the existing therapeutic armamentarium.
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INTRODUCTION: Although programmed cell death-1 inhibitors have become the mainstay of treatment for many cancers, their use can at times be accompanied by unusual side effects. CASE REPORT: We describe herein a 43-year-old patient with Lynch syndrome and colon cancer who developed facial swelling 18 months after starting nivolumab therapy. Our patient also experienced a grade 1 maculopapular rash due to this agent. Naranjo nomogram assessment showed a probable causality between nivolumab and angioedema (score of 8). MANAGEMENT & OUTCOME: Given the modest intensity of symptoms and the excellent response of metastatic colon cancer to nivolumab, this agent was continued without interruptions. She was prescribed prednisone 20â mg orally daily as needed to be taken if the swelling progressed, or if respiratory symptoms developed. The patient experienced another two similar episodes over the next months; however, they were self-limiting and did not require steroids. Subsequently, she had no further similar symptoms. DISCUSSION: Rare reports of angioedema associated with immune checkpoint inhibitor (ICI) treatment have previously been described. The exact mechanism of these phenomena is unknown, but bradykinin release leading to increased vascular permeability might be involved. Clinicians, pharmacists, and patients should be aware of this rare side effect of ICIs as it can be life-threatening when involving the respiratory tract and causing impending airway obstruction.
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Cardiac allograft vasculopathy (CAV), also known as cardiac transplant vasculopathy, is a major determinant of long-term survival among cardiac transplantation recipients. Histologically, CAV is featured by diffuse, concentric thickening of the vascular wall, and primarily affects large and small epicardial coronary arteries, intramyocardial arteries, and veins. Owing to graft denervation, CAV typically follows an insidious course, and patients may not experience classic angina symptoms but instead present with progressive heart failure or ventricular arrhythmias. Recent studies on biomarkers have furthered the knowledge concerning the prediction and prognosis of CAV. Given its association with metabolic, thrombotic, inflammatory, and immunologic markers, CAV is likely to represent a complex multifactorial process that involves both immune-mediated and non-immune-mediated pathways. In order to identify the high-risk patients that would benefit from early intervention, future research is warranted to examine the usefulness of a biomarker panel in CAV risk stratification.
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Transplante de Coração , Aloenxertos , Biomarcadores , Vasos Coronários , Transplante de Coração/efeitos adversos , Humanos , PrognósticoRESUMO
BACKGROUND: Intensive blood pressure (BP) lowering may offer protective effects against major adverse cardiac event (MACE) but is also associated with a greater risk of a serious adverse event (SAE). The risk-benefit profile of intensive versus standard BP control has not been comprehensively assessed. METHODS: Four studies were identified from a systematic literature search for randomized controlled trials comparing intensive versus standard BP lowering that reported both MACE and SAE endpoints. A previously described statistical approach was applied to characterize the efficacy-safety tradeoff of BP control. The bivariate outcome was computed to quantitatively assess the net clinical benefit (NCB) of intensive BP lowering as compared to standard treatment, with positive values indicating increased risks and negative values indicating decreased risks. RESULTS: Data from the SPRINT trial demonstrated that intensive strategy was superior in MACE but inferior in SAE, thereby eroding the NCB (bivariate outcome: 0.33% [-0.50% to 1.21%]). Intensive strategy from the SPS3 trial fulfilled non-inferiority in both MACE and SAE but did not reach a favorable NCB (-1.31% [-2.25% to 0.01%]). The ACCORD trial suggested that intensive strategy was non-inferior in MACE but inferior in SAE (-0.19% [-0.79% to 1.37%]). Results from the VALISH trial were inconclusive for SAE but suggested non-inferiority in MACE (-1.19% [-3.24% to 0.68%]). CONCLUSIONS: Compared to the standard blood pressure target, pooled data from randomized controlled trials suggest that intensive strategy did not achieve a net clinical benefit when weighing the benefit of MACE reduction against the risk of SAE under the bivariate framework. ABBREVIATIONS: Blood pressure (BP), diastolic blood pressure (DBP), major adverse cardiac event (MACE), net clinical benefit (NCB), serious adverse event (SAE), systolic blood pressure (SBP).
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Disruptions to the gut microbiota have been associated with adverse outcomes including graft-versus-host disease, infections, and mortality after hematopoietic cell transplantation and cellular therapy. Evidence for causal links is accumulating, thus supporting therapeutic interventions targeting the microbiota with the goal of preventing and treating adverse outcomes. One such intervention is fecal microbiota transplantation (FMT) by which an entire community of gut microbiota is transferred to the patient with dysbiosis. As this approach in transplant and cellular therapy recipients is still in its infancy, no best approach has been defined and many open questions need to be addressed before FMT becomes a standard treatment. In this review, we highlight microbiota-outcome associations with the highest level of evidence, provide an overview of the main FMT trials, and suggest some paths forward.
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Microbioma Gastrointestinal , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Humanos , Transplante de Microbiota Fecal , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Doença Enxerto-Hospedeiro/prevenção & controle , Disbiose/terapiaRESUMO
BACKGROUND Heparin-induced thrombocytopenia (HIT) is a serious adverse effect of heparin, which can lead to a prothrombotic state. Prompt cessation of heparin and initiation of non-heparin anticoagulation is the standard of care for HIT. Nevertheless, the treatment can pose challenges, particularly in refractory HIT, in patients with contraindications to anticoagulation, or those requiring urgent surgery. Additionally, in rare cases, conventional anticoagulation therapy is not effective, necessitating alternative treatments such as plasma exchange (PLEX) and intravenous immunoglobulin (IVIG). CASE REPORT Here, we report the case of a 57-year-old male patient who developed mild acute cellular rejection, refractory HIT, and disseminated intravascular coagulation after liver transplant surgery. Heparin was stopped and argatroban was initiated for thromboembolism treatment, but hepatic artery thrombosis occurred in the setting of refractory HIT and caused transplant failure. The patient underwent a second liver transplant 1 month after the first surgery. He had 2 sessions of PLEX and received 1 dose of IVIG before and 1 dose during the operation. Despite advanced treatment with PLEX and IVIG, the refractory HIT persisted. Hepatic artery thrombosis recurred within 2 weeks and the transplant failed again despite catheter-directed intra-arterial thrombolysis and argatroban therapy. CONCLUSIONS Recently perioperative PLEX and IVIG have been used a few times for the treatment of refractory HIT. This is the first reported case of a liver transplant recipient with refractory HIT who underwent this treatment strategy. Further investigation is required to determine the efficacy and safety of preoperative and intraoperative administration of PLEX and IVIG, especially in liver transplant recipients with HIT.
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Transplante de Fígado , Trombocitopenia , Trombose , Masculino , Humanos , Pessoa de Meia-Idade , Imunoglobulinas Intravenosas/uso terapêutico , Troca Plasmática , Transplante de Fígado/efeitos adversos , Trombocitopenia/induzido quimicamente , Trombocitopenia/terapia , Heparina/efeitos adversos , Trombose/tratamento farmacológico , Anticoagulantes/efeitos adversosRESUMO
Key features of immune memory are greater and faster antigen-specific antibody responses to repeat infection. In the setting of immune-evading viral evolution, it is important to understand how far antibody memory recognition stretches across viral variants when memory cells are recalled to action by repeat invasions. It is also important to understand how immune recall influences longevity of secreted antibody responses. We analyzed SARS-CoV-2 variant recognition; dynamics of memory B cells; and secreted antibody over time after infection, vaccination, and boosting. We find that a two-dose SARS-CoV-2 vaccination regimen given after natural infection generated greater longitudinal antibody stability and induced maximal antibody magnitudes with enhanced breadth across Beta, Gamma, Delta and Omicron variants. A homologous third messenger RNA vaccine dose in COVID-naïve individuals conferred greater cross-variant evenness of neutralization potency with stability that was equal to the hybrid immunity conferred by infection plus vaccination. Within unvaccinated individuals who recovered from COVID, enhanced antibody stability over time was observed within a subgroup of individuals who recovered more quickly from COVID and harbored significantly more memory B cells cross-reactive to endemic coronaviruses early after infection. These cross-reactive clones map to the conserved S2 region of SARS-CoV-2 spike with higher somatic hypermutation levels and greater target affinity. We conclude that SARS-CoV-2 antigen challenge histories in humans influence not only the speed and magnitude of antibody responses but also functional cross-variant antibody repertoire composition and longevity.
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COVID-19 , SARS-CoV-2 , Humanos , Vacinas contra COVID-19 , AnticorposRESUMO
Memory B cell reserves can generate protective antibodies against repeated SARS-CoV-2 infections, but with an unknown reach from original infection to antigenically drifted variants. We charted memory B cell receptor-encoded monoclonal antibodies (mAbs) from 19 COVID-19 convalescent subjects against SARS-CoV-2 spike (S) and found 7 major mAb competition groups against epitopes recurrently targeted across individuals. Inclusion of published and newly determined structures of mAb-S complexes identified corresponding epitopic regions. Group assignment correlated with cross-CoV-reactivity breadth, neutralization potency, and convergent antibody signatures. mAbs that competed for binding the original S isolate bound differentially to S variants, suggesting the protective importance of otherwise-redundant recognition. The results furnish a global atlas of the S-specific memory B cell repertoire and illustrate properties conferring robustness against emerging SARS-CoV-2 variants.
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Coronary artery tortuosity (CAT) is a prevalent angiographic finding commonly associated with aging, hypertension, atherosclerosis and other conditions. Preliminary evidence suggests that degradation of elastin, a key component of extracellular matrix in the vascular wall, may be responsible for the development of CAT. The clinical significance of CAT should be considered in several aspects. First, coronary flow alteration associated with CAT may result in myocardial ischemia owing to reduced perfusion pressure distal to the tortuous segment. Second, increased and oscillatory shear stress in the tortuous vessel may promote atherosclerotic plaque formation and acute coronary syndrome. Third, as one of the criteria for coronary lesion complexity, the presence of severe tortuosity proximal to the culprit lesion may pose a challenge to wiring and stent or balloon delivery, thereby increasing the risk of periprocedural complications. Last, the presence of CAT may serve as a diagnostic clue of concurrent vasculopathy such as fibromuscular dysplasia or spontaneous coronary artery dissection. In general, CAT represents a benign entity that does not require specific treatment or intervention. Further research is warranted to elucidate the pathogenesis and prognostic effect of coronary tortuosity.
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Doença da Artéria Coronariana/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Intervenção Coronária Percutânea/métodos , Distribuição por Idade , Aterosclerose/epidemiologia , Doenças do Tecido Conjuntivo/epidemiologia , Angiografia Coronária , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/fisiopatologia , Anomalias dos Vasos Coronários/epidemiologia , Vasos Coronários/fisiopatologia , Displasia Fibromuscular/epidemiologia , Humanos , Hipertensão/epidemiologia , Achados Incidentais , Isquemia Miocárdica/epidemiologia , Fatores de Risco , Distribuição por Sexo , Stents , Estresse Mecânico , Cardiomiopatia de Takotsubo/epidemiologia , Doenças Vasculares/congênito , Doenças Vasculares/epidemiologiaRESUMO
Understanding humoral responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is critical for improving diagnostics, therapeutics, and vaccines. Deep serological profiling of 232 coronavirus disease 2019 (COVID-19) patients and 190 pre-COVID-19 era controls using VirScan revealed more than 800 epitopes in the SARS-CoV-2 proteome, including 10 epitopes likely recognized by neutralizing antibodies. Preexisting antibodies in controls recognized SARS-CoV-2 ORF1, whereas only COVID-19 patient antibodies primarily recognized spike protein and nucleoprotein. A machine learning model trained on VirScan data predicted SARS-CoV-2 exposure history with 99% sensitivity and 98% specificity; a rapid Luminex-based diagnostic was developed from the most discriminatory SARS-CoV-2 peptides. Individuals with more severe COVID-19 exhibited stronger and broader SARS-CoV-2 responses, weaker antibody responses to prior infections, and higher incidence of cytomegalovirus and herpes simplex virus 1, possibly influenced by demographic covariates. Among hospitalized patients, males produce stronger SARS-CoV-2 antibody responses than females.
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COVID-19/imunologia , Mapeamento de Epitopos , Epitopos/imunologia , SARS-CoV-2/imunologia , Índice de Gravidade de Doença , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Formação de Anticorpos , COVID-19/sangue , Teste Sorológico para COVID-19 , Reações Cruzadas , Microscopia Crioeletrônica , Epitopos/química , Epitopos/genética , Feminino , Humanos , Masculino , Conformação Proteica , SoroconversãoRESUMO
The global coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has made the development of a vaccine a top biomedical priority. In this study, we developed a series of DNA vaccine candidates expressing different forms of the SARS-CoV-2 spike (S) protein and evaluated them in 35 rhesus macaques. Vaccinated animals developed humoral and cellular immune responses, including neutralizing antibody titers at levels comparable to those found in convalescent humans and macaques infected with SARS-CoV-2. After vaccination, all animals were challenged with SARS-CoV-2, and the vaccine encoding the full-length S protein resulted in >3.1 and >3.7 log10 reductions in median viral loads in bronchoalveolar lavage and nasal mucosa, respectively, as compared with viral loads in sham controls. Vaccine-elicited neutralizing antibody titers correlated with protective efficacy, suggesting an immune correlate of protection. These data demonstrate vaccine protection against SARS-CoV-2 in nonhuman primates.
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Betacoronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas de DNA/imunologia , Vacinas Virais/imunologia , Adjuvantes Imunológicos , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Betacoronavirus/fisiologia , Líquido da Lavagem Broncoalveolar/virologia , COVID-19 , Vacinas contra COVID-19 , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Modelos Animais de Doenças , Feminino , Humanos , Imunidade Celular , Imunidade Humoral , Imunização Secundária , Imunogenicidade da Vacina , Memória Imunológica , Macaca mulatta , Masculino , Proteínas Mutantes/química , Proteínas Mutantes/imunologia , Mucosa Nasal/virologia , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Domínios Proteicos , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Vacinação , Vacinas de DNA/administração & dosagem , Carga Viral , Vacinas Virais/administração & dosagemRESUMO
OBJECTIVES: The condition known as 'Mechanic's Hands' is a thickened, hyperkeratotic eruption, which is bilaterally symmetric along the fingers, and often occurs in patients with some connective tissue diseases. Nail fold capillaroscopy is a non-invasive technique for evaluation of connective tissue diseases. We evaluated the prevalence of mechanic hands in patients with connective tissue diseases and compared the clinical manifestations and capillaroscopic changes in the patients with and without mechanic hands. METHODS: The clinical manifestations and capillaroscopy of 576 patients with scleroderma, dermatomyositis, systemic lupus erythematosus, Sjogren's syndrome, undifferentiated and mixed connective tissue diseases were evaluated and compared in patients with and without mechanic hands. RESULTS: A total of 576 patients were enrolled. Mechanic hands were observed in 17.2% of patients: 50% of mixed connective tissue disease, 35% of dermatomyositis, 15.4% of scleroderma, 14.9% of undifferentiated connective tissue disease, 14.3% of Sjogren's syndrome, and no patient with SLE. Among them, 80.8% had abnormal capillaroscopic findings. In dermatomyositis patients, Raynaud's phenomenon, anti-Jo-1 positivity, and some capillaroscopy findings were detected more frequently in patients with mechanic hand. In scleroderma, positive Scl70 and capillary loss were observed more frequently in patients without mechanic hands. CONCLUSIONS: Mechanic hands can be a presenting sign of some systemic connective tissue diseases. Probably, finding this sign on examination, especially together with Raynaud's phenomenon or abnormal capillaroscopy, can be helpful in the early diagnosis of the connective tissue diseases and can be used as a predictive and prognostic tool in future studies.
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Doenças do Tecido Conjuntivo/diagnóstico , Dedos/diagnóstico por imagem , Ceratose/diagnóstico , Angioscopia Microscópica/métodos , Unhas/irrigação sanguínea , Adulto , Doenças do Tecido Conjuntivo/diagnóstico por imagem , Estudos Transversais , Feminino , Humanos , Ceratose/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Unhas/diagnóstico por imagem , Doença de Raynaud/diagnóstico , Doença de Raynaud/diagnóstico por imagemRESUMO
INTRODUCTION: Compared to other direct oral anticoagulants, betrixaban has a longer half-life, smaller peak-trough variance, minimal renal clearance, and minimal hepatic Cytochrome P (CYP) metabolism. The Acute Medically Ill VTE Prevention with Extended Duration Betrixaban (APEX) trial evaluated the efficacy and safety of extended duration betrixaban compared to standard duration enoxaparin in acutely ill hospitalized patients. Areas covered: This article describes the role of betrixaban in the prevention of venous thromboembolism (VTE) in acutely ill medical patients. This article provides a consolidated summary of the primary APEX study findings as well as prespecified and exploratory substudies. This article also provides a review of the results of studies in which other direct factor Xa inhibitors have been evaluated in an extended duration regimen in this patient population. Expert commentary: While previous agents have demonstrated that extended duration VTE prophylaxis can be efficacious, betrixaban is the first agent to demonstrate efficacy without an increase in major bleeding. The totality of the data from the APEX trial supports extended duration betrixaban for VTE prophylaxis in the acute medically ill patient population. As such, betrixaban has been approved in the USA for extended VTE prophylaxis in at-risk acute medically ill patients.
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Benzamidas/uso terapêutico , Inibidores do Fator Xa/uso terapêutico , Piridinas/uso terapêutico , Tromboembolia Venosa/prevenção & controle , Anticoagulantes/uso terapêutico , Enoxaparina/uso terapêutico , Hemorragia/induzido quimicamente , Humanos , Fatores de RiscoRESUMO
Polycystic ovary syndrome (PCOS) is one of the most common reproductive endocrine disorders among women of reproductive age, with a variety of complications and consequences mostly due to hyperandrogenism and insulin resistance (IR). PCOS patients with IR are at risk for metabolic syndrome and diabetes mellitus (DM) along with its complications such as cardiovascular events. There are several methods for screening IR in patients with PCOS to predict DM and other complications. Fasting plasma glucose test, oral glucose tolerance test, and insulin and glycosylated hemoglobin (HbA1c) levels are some available screening tools for IR. The American Diabetes Association recommended HbA1c to screen for DM because HbA1c is not affected by day-to-day plasma glucose levels and reflects the plasma glucose status during 2-3 months before measurement. Some studies have evaluated the role of HbA1c as a screening method to predict DM in PCOS patients, however, there are still controversies in this matter. Also some studies reported that HbA1c has a correlation with complications of PCOS such as metabolic syndrome and cardiovascular events. We found that HbA1c could be a suitable screening test for IR in PCOS patients but more studies are recommended, omitting confounding factors that could affect IR in patients with PCOS, such as antihyperglycemic agents like metformin, or lifestyle modification, which can be effective in reducing IR in patients with PCOS.
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Hemoglobinas Glicadas/análise , Síndrome do Ovário Policístico/sangue , Adulto , Diabetes Mellitus Tipo 2/etiologia , Feminino , Humanos , Resistência à Insulina/fisiologia , Síndrome do Ovário Policístico/complicações , Valor Preditivo dos Testes , Fatores de RiscoRESUMO
One of the main areas of behavioural neuroscience is forecasting the human behaviour. Epilepsy is a central nervous system disorder in which nerve cell activity in the brain becomes disrupted, causing seizures or periods of unusual behaviour, sensations and sometimes loss of consciousness. An estimated 5% of the world population has epileptic seizure but there is not any method to cure it. More than 30% of people with epilepsy cannot control seizure. Epileptic seizure prediction, refers to forecasting the occurrence of epileptic seizures, is one of the most important but challenging problems in biomedical sciences, across the world. In this research we propose a new methodology which is based on studying the EEG signals using two measures, the Hurst exponent and fractal dimension. In order to validate the proposed method, it is applied to epileptic EEG signals of patients by computing the Hurst exponent and fractal dimension, and then the results are validated versus the reference data. The results of these analyses show that we are able to forecast the onset of a seizure on average of 25.76 seconds before the time of occurrence.
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Algoritmos , Eletroencefalografia/métodos , Epilepsia/fisiopatologia , Convulsões/fisiopatologia , Processamento de Sinais Assistido por Computador , Adulto , Epilepsia/diagnóstico , Feminino , Fractais , Humanos , Masculino , Prognóstico , Reprodutibilidade dos Testes , Convulsões/diagnóstico , Sensibilidade e Especificidade , Fatores de Tempo , Adulto JovemRESUMO
One of the major challenges in brain research is to relate the structural features of the auditory stimulus to structural features of Electroencephalogram (EEG) signal. Memory content is an important feature of EEG signal and accordingly the brain. On the other hand, the memory content can also be considered in case of stimulus. Beside all works done on analysis of the effect of stimuli on human EEG and brain memory, no work discussed about the stimulus memory and also the relationship that may exist between the memory content of stimulus and the memory content of EEG signal. For this purpose we consider the Hurst exponent as the measure of memory. This study reveals the plasticity of human EEG signals in relation to the auditory stimuli. For the first time we demonstrated that the memory content of an EEG signal shifts towards the memory content of the auditory stimulus used. The results of this analysis showed that an auditory stimulus with higher memory content causes a larger increment in the memory content of an EEG signal. For the verification of this result, we benefit from approximate entropy as indicator of time series randomness. The capability, observed in this research, can be further investigated in relation to human memory.