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1.
Proc Natl Acad Sci U S A ; 121(17): e2314772121, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38621122

RESUMO

Dynamic networks composed of constituents that break and reform bonds reversibly are ubiquitous in nature owing to their modular architectures that enable functions like energy dissipation, self-healing, and even activity. While bond breaking depends only on the current configuration of attachment in these networks, reattachment depends also on the proximity of constituents. Therefore, dynamic networks composed of macroscale constituents (not benefited by the secondary interactions cohering analogous networks composed of molecular-scale constituents) must rely on primary bonds for cohesion and self-repair. Toward understanding how such macroscale networks might adaptively achieve this, we explore the uniaxial tensile response of 2D rafts composed of interlinked fire ants (S. invicta). Through experiments and discrete numerical modeling, we find that ant rafts adaptively stabilize their bonded ant-to-ant interactions in response to tensile strains, indicating catch bond dynamics. Consequently, low-strain rates that should theoretically induce creep mechanics of these rafts instead induce elastic-like response. Our results suggest that this force-stabilization delays dissolution of the rafts and improves toughness. Nevertheless, above 35[Formula: see text] strain low cohesion and stress localization cause nucleation and growth of voids whose coalescence patterns result from force-stabilization. These voids mitigate structural repair until initial raft densities are restored and ants can reconnect across defects. However mechanical recovery of ant rafts during cyclic loading suggests that-even upon reinstatement of initial densities-ants exhibit slower repair kinetics if they were recently loaded at faster strain rates. These results exemplify fire ants' status as active agents capable of memory-driven, stimuli-response for potential inspiration of adaptive structural materials.


Assuntos
Formigas , Formigas Lava-Pés , Animais , Formigas/fisiologia , Física , Microdomínios da Membrana
2.
Microvasc Res ; 154: 104686, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38614154

RESUMO

Pulmonary hypertension (PH) is a chronic, progressive condition in which respiratory muscle dysfunction is a primary contributor to exercise intolerance and dyspnea in patients. Contractile function, blood flow distribution, and the hyperemic response are altered in the diaphragm with PH, and we sought to determine whether this may be attributed, in part, to impaired vasoreactivity of the resistance vasculature. We hypothesized that there would be blunted endothelium-dependent vasodilation and impaired myogenic responsiveness in arterioles from the diaphragm of PH rats. Female Sprague-Dawley rats were randomized into healthy control (HC, n = 9) and monocrotaline-induced PH rats (MCT, n = 9). Endothelium-dependent and -independent vasodilation and myogenic responses were assessed in first-order arterioles (1As) from the medial costal diaphragm in vitro. There was a significant reduction in endothelium-dependent (via acetylcholine; HC, 78 ± 15% vs. MCT, 47 ± 17%; P < 0.05) and -independent (via sodium nitroprusside; HC, 89 ± 10% vs. MCT, 66 ± 10%; P < 0.05) vasodilation in 1As from MCT rats. MCT-induced PH also diminished myogenic constriction (P < 0.05) but did not alter passive pressure responses. The diaphragmatic weakness, impaired hyperemia, and blood flow redistribution associated with PH may be due, in part, to diaphragm vascular dysfunction and thus compromised oxygen delivery which occurs through both endothelium-dependent and -independent mechanisms.


Assuntos
Diafragma , Hipertensão Pulmonar , Ratos Sprague-Dawley , Vasodilatação , Animais , Feminino , Hipertensão Pulmonar/fisiopatologia , Hipertensão Pulmonar/induzido quimicamente , Hipertensão Pulmonar/etiologia , Arteríolas/fisiopatologia , Diafragma/fisiopatologia , Diafragma/irrigação sanguínea , Modelos Animais de Doenças , Vasodilatadores/farmacologia , Endotélio Vascular/fisiopatologia , Vasoconstrição , Monocrotalina/toxicidade , Ratos
3.
Alzheimers Dement ; 20(5): 3543-3550, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38624069

RESUMO

INTRODUCTION: Alzheimer's disease (AD) is characterized by cognitive impairments; however, heightened anxiety often accompanies and, in some cases, exacerbates cognitive its. The present study aims to understand the influence of multiple variables on anxiety-like behavior in TgF344-AD rats and determine whether anxiety impacts memory performance. METHODS: An elevated plus maze was used to assess anxiety-like behavior in the established colony (n = 107). Influences of age, sex, genotype, and exercise on anxiety were evaluated via multiple linear regression. Correlation analysis evaluated the relationship between anxiety and memory performance. RESULTS: Age (P < 0.05) and AD genotype (P < 0.001) were associated with increasing anxiety, while exercise (P < 0.05) was associated with decreasing anxiety. Female AD animals displayed more anxiety-like behavior versus wild-type female (P < 0.001) and AD male (P < 0.05) littermates. DISCUSSION: Concluding that while factors such as age, sex, AD genotype, and training status can impact anxiety levels in the TgF344-AD model, anxiety level did not impact memory performance. HIGHLIGHTS: Increased anxiety-like behavior in TgF344-AD rats does not correlate with declines in memory performance. Predictors of higher anxiety-like behaviors in the TgF344-AD rat include age, Alzheimer's disease (AD) genotype, and sex with female AD animals experiencing greater anxiety compared to female wild-type or male AD. Exercise training leads to decreased anxiety-like behaviors in the TgF344-AD rat.


Assuntos
Doença de Alzheimer , Ansiedade , Modelos Animais de Doenças , Genótipo , Condicionamento Físico Animal , Ratos Transgênicos , Animais , Doença de Alzheimer/genética , Feminino , Masculino , Ratos , Ansiedade/genética , Fatores Sexuais , Memória/fisiologia , Fatores Etários , Ratos Endogâmicos F344 , Aprendizagem em Labirinto/fisiologia
4.
Sensors (Basel) ; 22(7)2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35408154

RESUMO

Dehydration in the human body arises due to inadequate replenishment of fluids. An appropriate level of hydration is essential for optimal functioning of the human body, and complications ranging from mild discomfort to, in severe cases, death, could result from a neglected imbalance in fluid levels. Regular and accurate monitoring of hydration status can provide meaningful information for people operating in stressful environmental conditions, such as athletes, military professionals and the elderly. In this study, we propose a non-invasive hydration monitoring technique employing non-ionizing electromagnetic power in the microwave band to estimate the changes in the water content of the whole body. Specifically, we investigate changes in the attenuation coefficient in the frequency range 2-3.5 GHz between a pair of planar antennas positioned across a participant's arm during various states of hydration. Twenty healthy young adults (10M, 10F) underwent controlled hypohydration and euhydration control bouts. The attenuation coefficient was compared among trials and used to predict changes in body mass. Volunteers lost 1.50±0.44% and 0.49±0.54% body mass during hypohydration and euhydration, respectively. The microwave transmission-based attenuation coefficient (2-3.5 GHz) was accurate in predicting changes in hydration status. The corresponding regression analysis demonstrates that building separate estimation models for dehydration and rehydration phases offer better predictive performance (88%) relative to a common model for both the phases (76%).


Assuntos
Desidratação , Micro-Ondas , Idoso , Atletas , Desidratação/etiologia , Hidratação/efeitos adversos , Humanos , Água , Adulto Jovem
5.
Health Commun ; 30(6): 525-35, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24991918

RESUMO

This study examines the dialectical tensions experienced by home hospice nurses in interactions with patients, families, and health care providers. In-depth, semistructured interviews were conducted with 24 home hospice nurses from a mid-size for-profit hospice organization serving approximately 230 patients on an annual basis. Interviews revealed hospice nurses experience both interpersonal and organizational dialectics during hospice interactions: authoritative-nonauthoritative, revelation-concealment, independence-collaboration, and quality of care-business of care. Dialectics often resulted as a by-product of (a) responding to expectations and care choices of patients and families particular to the emotionally charged home context, (b) obtaining authorization from health care providers who are not members of the interdisciplinary team, and (c) pressures associated with providing quality patient care while fulfilling organizational role requirements. The praxis strategies used to negotiate tensions included segmentation, balance, recalibration, and spiraling inversion. Specifically, nurses employed strategies such as ascertaining family/patient acceptance, using persuasive tactics when communicating with external health care providers, relying on effective time management, and working off the clock to provide more in-person care. Although functional for patients and hospice organizations, nurses who continually rely on these strategies may experience job stress when their interpersonal commitments repeatedly conflict with organizational role demands.


Assuntos
Comunicação , Enfermagem Domiciliar , Enfermagem de Cuidados Paliativos na Terminalidade da Vida , Relações Interprofissionais , Relações Enfermeiro-Paciente , Enfermeiros de Saúde Comunitária/psicologia , Relações Profissional-Família , Adulto , Comportamento Cooperativo , Feminino , Pessoal de Saúde/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Enfermeiros de Saúde Comunitária/estatística & dados numéricos , Pesquisa Qualitativa
6.
MMWR Morb Mortal Wkly Rep ; 63(11): 234-6, 2014 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-24647399

RESUMO

For more than two decades, as the number of tuberculosis (TB) cases overall in the United States has declined, the proportion of cases among foreign-born persons has increased. In 2013, the percentage of TB cases among those born outside the country was 64.6%. To address this trend, CDC has developed strategies to identify and treat TB in U.S.-bound immigrants and refugees overseas. Each year, approximately 450,000 persons are admitted to the United States on an immigrant visa, and 50,000-70,000 are admitted as refugees. Applicants for either an immigrant visa or refugee status are required to undergo a medical examination overseas before being allowed to travel to the United States. CDC is the federal agency with regulatory oversight of the overseas medical examination, and panel physicians appointed by the U.S. Department of State perform the examinations in accordance with Technical Instructions (TI) provided by CDC's Division of Global Migration and Quarantine (DGMQ). Beginning in 1991, the algorithm for TB TI relied on chest radiographs for applicants aged ≥15 years, followed by sputum smears for those with findings suggestive of TB; no additional diagnostics were used. In 2007, CDC issued enhanced standards for TB diagnosis and treatment, including the addition of sputum cultures (which are more sensitive than smears) as a diagnostic tool and treatment delivered as directly observed therapy (DOT). This report summarizes worldwide implementation of the new screening requirements since 2007. In 2012, the year for which the most recent data are available, 60% of the TB cases diagnosed were in persons with smear-negative, but culture-positive, test results. The results demonstrate that rigorous diagnostic and treatment programs can be implemented in areas with high TB incidence overseas.


Assuntos
Emigrantes e Imigrantes/legislação & jurisprudência , Programas de Rastreamento/legislação & jurisprudência , Desenvolvimento de Programas , Refugiados/legislação & jurisprudência , Tuberculose/diagnóstico , Adolescente , Centers for Disease Control and Prevention, U.S. , Criança , Pré-Escolar , Resistência Microbiana a Medicamentos , Emigração e Imigração/estatística & dados numéricos , Humanos , Testes de Liberação de Interferon-gama , Programas de Rastreamento/métodos , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/isolamento & purificação , Guias de Prática Clínica como Assunto , Escarro/microbiologia , Teste Tuberculínico , Tuberculose/epidemiologia , Tuberculose/terapia , Estados Unidos/epidemiologia
7.
J Mol Med (Berl) ; 102(6): 751-760, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38639785

RESUMO

Annexins, a group of Ca2+-dependent phospholipid-binding proteins, exert diverse roles in neuronal development, normal central nervous system (CNS) functioning, neurological disorders, and CNS tumors. This paper reviews the roles of individual annexins (A1-A13) in these contexts. Annexins possess unique structural and functional features, such as Ca2+-dependent binding to phospholipids, participating in membrane organization, and modulating cell signaling. They are implicated in various CNS processes, including endocytosis, exocytosis, and stabilization of plasma membranes. Annexins exhibit dynamic roles in neuronal development, influencing differentiation, proliferation, and synaptic formation in CNS tissues. Notably, annexins such as ANXA1 and ANXA2 play roles in apoptosis and blood-brain barrier (BBB) integrity. Neurological disorders, including Alzheimer's disease, multiple sclerosis, and depression, involve annexin dysregulation, influencing neuroinflammation, blood-brain barrier integrity, and stress responses. Moreover, annexins contribute to the pathogenesis of CNS tumors, either promoting or suppressing tumor growth, angiogenesis, and invasion. Annexin expression patterns vary across different CNS tumor types, providing potential prognostic markers and therapeutic targets. This review underscores the multifaceted roles of annexins in the CNS, highlighting their importance in normal functioning, disease progression, and potential therapeutic interventions.


Assuntos
Anexinas , Sistema Nervoso Central , Humanos , Anexinas/metabolismo , Animais , Sistema Nervoso Central/metabolismo , Barreira Hematoencefálica/metabolismo , Doenças do Sistema Nervoso Central/metabolismo , Doenças do Sistema Nervoso Central/patologia , Neoplasias do Sistema Nervoso Central/metabolismo , Neoplasias do Sistema Nervoso Central/patologia
8.
Front Microbiol ; 14: 1155388, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37901813

RESUMO

Inflammatory Bowel Disease (IBD) is characterized by prolonged inflammation of the gastrointestinal tract, which is thought to occur due to dysregulation of the immune system allowing the host's cells to attack the GI tract and cause chronic inflammation. IBD can be caused by numerous factors such as genetics, gut microbiota, and environmental influences. In recent years, emphasis on commensal bacteria as a critical player in IBD has been at the forefront of new research. Each individual harbors a unique bacterial community that is influenced by diet, environment, and sanitary conditions. Importantly, it has been shown that there is a complex relationship among the microbiome, activation of the immune system, and autoimmune disorders. Studies have shown that not only does the microbiome possess pathogenic roles in the progression of IBD, but it can also play a protective role in mediating tissue damage. Therefore, to improve current IBD treatments, understanding not only the role of harmful bacteria but also the beneficial bacteria could lead to attractive new drug targets. Due to the considerable diversity of the microbiome, it has been challenging to characterize how particular microorganisms interact with the host and other microbiota. Fortunately, with the emergence of next-generation sequencing and the increased prevalence of germ-free animal models there has been significant advancement in microbiome studies. By utilizing human IBD studies and IBD mouse models focused on intraepithelial lymphocytes and innate lymphoid cells, this review will explore the multifaceted roles the microbiota plays in influencing the immune system in IBD.

9.
Cell Mol Gastroenterol Hepatol ; 15(4): 903-919, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36535508

RESUMO

BACKGROUND & AIMS: Down-regulation of chloride transporter SLC26A3 or down-regulated in adenoma (DRA) in colonocytes has recently been linked to the pathogenesis of ulcerative colitis (UC). Because exaggerated immune responses are one of the hallmarks of UC, these current studies were undertaken to define the mechanisms by which loss of DRA relays signals to immune cells to increase susceptibility to inflammation. METHODS: NanoString Immunology Panel, fluorescence assisted cell sorting, immunoblotting, immunofluorescence, and quantitative real-time polymerase chain reaction assays were used in wild-type and DRA knockout (KO) mice. Interleukin (IL)-33 blocking was used to determine specific changes in immune cells and co-housing/broad spectrum antibiotics administration, and ex vivo studies in colonoids were conducted to rule out the involvement of microbiota. Colonoid-derived monolayers from healthy and UC patient biopsies were analyzed for translatability. RESULTS: There was a marked induction of Th2 (>2-fold), CD4+ Th2 cells (∼8-fold), RORγt+ Th17, and FOXP3+ regulatory T cells (Tregs). DRA KO colons also exhibited a robust induction of IL-33 (>8-fold). In vivo studies using blocking of IL-33 established that T2 immune dysregulation (alterations in ILC2, Th2, and GATA3+ iTregs) in response to loss of DRA was due to altered epithelial-immune cell crosstalk via IL-33. CONCLUSIONS: Loss of DRA in colonocytes triggers the release of IL-33 to drive a type 2 immune response. These observations emphasize the critical importance of DRA in mucosal immune homeostasis and its implications in the pathogenesis of UC.


Assuntos
Colite Ulcerativa , Interleucina-33 , Animais , Camundongos , Interleucina-33/metabolismo , Imunidade Inata , Linfócitos T CD4-Positivos , Transportadores de Sulfato/genética , Transportadores de Sulfato/metabolismo , Antiporters/metabolismo
10.
Ann Med ; 55(2): 2269586, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37883807

RESUMO

OBJECTIVE: Athletes are susceptible to acute respiratory tract infections, including SARS-CoV-2, which can affect cardiovascular function. We aimed to evaluate the impact of COVID-19 infection and quarantine on cardiac function in male and female collegiate athletes. METHODS: We conducted a single-center, prospective, case-control study and performed transthoracic echocardiography in a diverse group of convalescent SARS-CoV-2-positive athletes following a 10-14-day quarantine, matched to non-SARS-CoV-2 athletes. Data collection occurred from August 1, 2020, to May 31, 2021. RESULTS: We evaluated 61 SARS-CoV-2-positive athletes (20 ± 1 years, 39% female) and 61 controls (age 20 ± 2 years, 39% female). Echocardiography in SARS-CoV-2-positive athletes was performed on average 40 ± 38 days after infection diagnosis. All SARS-CoV-2-positive athletes had clinically normal systolic left ventricular function (LVEF > 50%). However, SARS-CoV-2-positive athletes exhibited mildly lower LVEF compared to controls (65 ± 6% vs. 72 ± 8%, respectively, p < 0.001), which remained significant when evaluated separately for female and male athletes. Sub-analysis revealed these differences occurred only when imaging occurred within a mean average of 27 days of infection, with a longer recovery period (≥27 days) resulting in no differences. SARS-CoV-2-positive male athletes exhibited higher left ventricular end-diastolic volume and mitral filling velocities compared to male controls. CONCLUSION: Our study reveals unique sex-specific cardiac changes in collegiate athletes following SARS-CoV-2 infection and quarantine compared to controls. Despite a mild reduction in LVEF, which was only observed in the first weeks following infection, no clinically significant cardiac abnormalities were observed. Further research is required to understand if the changes in LVEF are directly attributed to the infection or indirectly through exercise restrictions resulting from quarantine.


Assuntos
COVID-19 , Humanos , Masculino , Feminino , Adolescente , Adulto Jovem , Adulto , COVID-19/diagnóstico , SARS-CoV-2 , Estudos de Casos e Controles , Quarentena , Atletas
11.
J Immigr Minor Health ; 25(6): 1295-1301, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37639043

RESUMO

The COVID-19 pandemic presents global health, welfare, and economic concerns. The agricultural workforce has experienced adverse effects, placing the U.S. food supply at risk. Agricultural workers temporarily travel to the United States on H-2A visas to supplement the agricultural workforce. Approximately 300,000 agricultural workers enter the United States with H-2A visas each year; over 90.0% are from Mexico. During February-May 2021, a COVID-19 testing pilot was performed with Clínica Médica Internacional (CMI), a clinic that performs medical examinations for US-bound immigrants, to determine the SARS-CoV-2 infection status of H-2A agricultural workers in Mexico before entry to the US. The CerTest VIASURE Real Time PCR Detection Kit was used. Participants' demographic information, test results, and testing turnaround times were collected. Workers who tested positive for SARS-CoV-2 completed isolation before US entry. During the pilot, 1195 H-2A workers were tested; 15 (1.3%) tested positive. Average reporting time was 31 h after specimen collection. This pilot demonstrated there is interest from H-2A employers and agents in testing the H-2A community before US entry. Testing for SARS-CoV-2 can yield public health benefit, is feasible, and does not delay entry of temporary agricultural workers to the US.


Assuntos
Teste para COVID-19 , COVID-19 , Estados Unidos/epidemiologia , Humanos , COVID-19/diagnóstico , SARS-CoV-2 , México , Fazendeiros , Pandemias
12.
J Cancer Res Ther ; 19(5): 1103-1108, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37787270

RESUMO

Introduction: In two Korean and Italian studies, the adherence rate (AR) to ASSLD 2005 guidelines in the management of hepatocellular carcinoma (HCC) was 60%. In a US study, the AR to American Association for the Study of Liver Disease (AASLD) 2005 guidelines was 73.3%, 26.8%, 25.3%, and 58.8% for patients with Barcelona Clinic Liver Cancer (BCLC) Stage A, B, C, and D, respectively, and nonadherence to guidelines was associated with longer overall survival (OS) in patients with BCLC Stage D. Here, we explored the AR to AASLD 2018 guidelines and its impact on OS. Methods: Between 2017 and 2019, 148 unique treatment-naïve patients with HCC were identified. Patients were staged according to the BCLC staging system and their AR to AASLD 2018 guidelines was noted. OS was estimated using Kaplan-Meier method. Survivals among patients from different groups was compared using Log-rank test. Results: The overall AR to AASLD 2018 guidelines was 83%. The AR for BCLC Stages 0, A, B, C, and D were 100%, 97%, 77%, 77%, and 38%, respectively. In patients with BCLC Stage D, the OS of patients treated with modalities adherent versus nonadherent to AASLD 2018 guidelines was 0.03 vs. 5.2 months (P = 0.0005). Otherwise, adherence versus nonadherence to AASLD 2018 guidelines showed no statistically significant differences in OS for patients with BCLC Stages 0, A, B, and C. Conclusion: The overall AR to AASLD 2018 guidelines was 83%. Nonadherence to AASLD 2018 guidelines in patients with BCLC Stage D translated into better OS.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Estadiamento de Neoplasias , Estudos Retrospectivos , Itália , Prognóstico
13.
JCI Insight ; 7(11)2022 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-35511435

RESUMO

Studies have demonstrated the phenotypic heterogeneity of vascular endothelial cells (ECs) within a vascular bed; however, little is known about how distinct endothelial subpopulations in a particular organ respond to an inflammatory stimulus. We performed single-cell RNA-Seq of 35,973 lung ECs obtained during baseline as well as postinjury time points after inflammatory lung injury induced by LPS. Seurat clustering and gene expression pathway analysis identified 2 major subpopulations in the lung microvascular endothelium, a subpopulation enriched for expression of immune response genes such as MHC genes (immuneEC) and another defined by increased expression of vascular development genes such as Sox17 (devEC). The presence of immuneEC and devEC subpopulations was also observed in nonhuman primate lungs infected with SARS-CoV-2 and murine lungs infected with H1N1 influenza virus. After the peak of inflammatory injury, we observed the emergence of a proliferative lung EC subpopulation. Overexpression of Sox17 prevented inflammatory activation in ECs. Thus, there appeared to be a "division of labor" within the lung microvascular endothelium in which some ECs showed propensity for inflammatory signaling and others for endothelial regeneration. These results provide underpinnings for the development of targeted therapies to limit inflammatory lung injury and promote regeneration.


Assuntos
COVID-19 , Vírus da Influenza A Subtipo H1N1 , Lesão Pulmonar , Animais , Células Endoteliais/metabolismo , Pulmão/metabolismo , Lesão Pulmonar/metabolismo , Camundongos , SARS-CoV-2 , Transcriptoma
14.
JCI Insight ; 7(9)2022 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-35349492

RESUMO

Long-term impairment in T cell-mediated adaptive immunity is a major clinical obstacle following treatment of blood disorders with hematopoietic stem cell transplantation. Although T cell development in the thymus has been extensively characterized, there are significant gaps in our understanding of prethymic processes that influence early T cell potential. We have uncovered a Notch/IL-21 signaling axis in bone marrow common lymphoid progenitor (CLP) cells. IL-21 receptor expression was driven by Notch activation in CLPs, and in vivo treatment with IL-21 induced Notch-dependent CLP proliferation. Taking advantage of this potentially novel signaling axis, we generated T cell progenitors ex vivo, which improved repopulation of the thymus and peripheral lymphoid organs of mice in an allogeneic transplant model. Importantly, Notch and IL-21 activation were equally effective in the priming and expansion of human cord blood cells toward the T cell fate, confirming the translational potential of the combined treatment.


Assuntos
Células-Tronco Hematopoéticas , Linfócitos T , Animais , Medula Óssea/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Interleucinas , Camundongos , Transdução de Sinais
15.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 10): o2553, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22058730

RESUMO

The title compound, C(12)H(22)NSi(+)·Cl(-), contains two formula units in the asymmetric unit and is a hydro-chloride salt in which the amine N atom is protonated and the NH(3) (+) group forms hydrogen bonds with the Cl(-) anion, forming a ribbon in the c-axis direction.

16.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 10): o2694, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22058791

RESUMO

In the title crystal structure, C(12)H(22)NOSi(+)·Cl(-), anions and cations are linked via O-H⋯Cl, N-H⋯Cl and N-H⋯O hydrogen bonds to form a two-dimensional network parallel to (101). Within the hydrogen-bonded network, R(4) (2)(22) ring motifs are stacked along [010].

17.
Adv Radiat Oncol ; 6(1): 100560, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33869897

RESUMO

PURPOSE: Our purpose was to assess the terminology used to describe the different oncologic subspecialties at academic institutions in the United States and determine whether the use of the term "oncologist" to describe a medical oncologist (MO) may affect the multidisciplinary care of patients with cancer. METHODS AND MATERIALS: An electronic survey was sent to chairs and program directors at all 94 academic radiation oncology departments in the United States. Questions assessed the terminology used to describe the oncologic subspecialties in their hospital's electronic medical record system, their views on how that terminology may affect referral patterns, and the perception of radiation oncologists' (ROs) role in patient care. RESULTS: Responses were received from 40 institutions (response rate, 42.6%). Fifteen percent of hospital electronic medical record systems used the term "oncology" instead of "medical oncology" (51%) or "hematology/oncology" (28%). Describing MOs simply as "oncologists" was thought to more likely affect patient views of MOs as the primary decision maker in their cancer care (mean Likert-type rating, 3.43) than it would affect the probability of up-front multidisciplinary referrals (mean Likert-type rating, 2.69). Patient perceptions of ROs as equal partners in care were thought to be less associated with the terminology used to describe MOs (mean Likert-type rating, 3.15) than the behavior of ROs in patient care (mean Likert-type rating, 4.65; P < .001), the attitude of MOs toward ROs (mean Likert-type rating, 4.59; P < .001), and the involvement of ROs in the initial new patient visits rather than a downstream referral (mean Likert-type rating, 3.95; P < .001). CONCLUSIONS: The terminology used to describe MOs was thought to affect patient and provider perceptions of RO, but less so than other patient-provider interaction factors.

18.
Respir Physiol Neurobiol ; 293: 103718, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34126260

RESUMO

We tested the hypothesis that limb vascular conductance (LVC) would increase during the immediate recovery phase of dynamic exercise above, but not below, critical power (CP) indicating a threshold for muscular contraction-induced impedance of limb blood flow (LBF). CP (115 ± 26 W) was determined in 7 men and 7 women who subsequently performed ∼5 min of near-supine cycling exercise both below and above CP. LVC demonstrated a greater increase during immediate recovery and remained significantly higher following exercise above, compared to below, CP (all p < 0.001). Power output was associated with the immediate increases in LVC following exercise above, but not below, CP (p < 0.001; r = 0.85). Additionally, variance in percent LBF impedance was significantly lower above (CV: 10.7 %), compared to below (CV: 53.2 %), CP (p < 0.01). CP appears to represent a threshold above which the characteristics of LBF impedance by muscular contraction become intensity-dependent. These data suggest a critical level of LBF impedance relative to contraction intensity exists and, once attained, may promote the progressive metabolic and neuromuscular responses known to occur above CP.


Assuntos
Circulação Sanguínea/fisiologia , Exercício Físico/fisiologia , Extremidade Inferior/fisiologia , Contração Muscular/fisiologia , Músculo Esquelético/fisiologia , Adulto , Ciclismo/fisiologia , Impedância Elétrica , Feminino , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/fisiologia , Humanos , Masculino , Ultrassonografia Doppler , Adulto Jovem
19.
Respir Physiol Neurobiol ; 294: 103765, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34352384

RESUMO

INTRODUCTION: Concerns have been raised that COVID-19 face coverings compromise lung function and pulmonary gas exchange to the extent that they produce arterial hypoxemia and hypercapnia during high intensity exercise resulting in exercise intolerance in recreational exercisers. This study therefore aimed to investigate the effects of a surgical, flannel or vertical-fold N95 masks on cardiorespiratory responses to incremental exercise. METHODS: This investigation studied 11 adult males and females at rest and while performing progressive cycle exercise to exhaustion. We tested the hypotheses that wearing a surgical (S), flannel (F) or horizontal-fold N95 mask compared to no mask (control) would not promote arterial deoxygenation or exercise intolerance nor alter primary cardiovascular variables during submaximal or maximal exercise. RESULTS: Despite the masks significantly increasing end-expired peri-oral %CO2 and reducing %O2, each ∼0.8-2% during exercise (P < 0.05), our results supported the hypotheses. Specifically, none of these masks reduced sub-maximal or maximal exercise arterial O2 saturation (P = 0.744), but ratings of dyspnea were significantly increased (P = 0.007). Moreover, maximal exercise capacity was not compromised nor were there any significant alterations of primary cardiovascular responses (mean arterial pressure, stroke volume, cardiac output) found during sub-maximal exercise. CONCLUSION: Whereas these results are for young healthy recreational male and female exercisers and cannot be applied directly to elite athletes, older or patient populations, they do support that arterial hypoxemia and exercise intolerance are not the obligatory consequences of COVID-19-indicated mask-wearing at least for cycling exercise.


Assuntos
COVID-19/prevenção & controle , Tolerância ao Exercício/fisiologia , Máscaras/efeitos adversos , Oxigênio/sangue , Adulto , Feminino , Humanos , Masculino , SARS-CoV-2
20.
J Clin Transl Endocrinol ; 21: 100231, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32695611

RESUMO

OBJECTIVES: Surveys for U.S. diabetes surveillance do not reliably distinguish between type 1 and type 2 diabetes, potentially obscuring trends in type 1 among adults. To validate survey-based algorithms for distinguishing diabetes type, we linked survey data collected from adult patients with diabetes to a gold standard diabetes type. RESEARCH DESIGN AND METHODS: We collected data through a telephone survey of 771 adults with diabetes receiving care in a large healthcare system in North Carolina. We tested 34 survey classification algorithms utilizing information on respondents' report of physician-diagnosed diabetes type, age at onset, diabetes drug use, and body mass index. Algorithms were evaluated by calculating type 1 and type 2 sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) relative to a gold standard diagnosis of diabetes type determined through analysis of EHR data and endocrinologist review of selected cases. RESULTS: Algorithms based on self-reported type outperformed those based solely on other data elements. The top-performing algorithm classified as type 1 all respondents who reported type 1 and were prescribed insulin, as "other diabetes type" all respondents who reported "other," and as type 2 the remaining respondents (type 1 sensitivity 91.6%, type 1 specificity 98.9%, type 1 PPV 82.5%, type 1 NPV 99.5%). This algorithm performed well in most demographic subpopulations. CONCLUSIONS: The major federal health surveys should consider including self-reported diabetes type if they do not already, as the gains in the accuracy of typing are substantial compared to classifications based on other data elements. This study provides much-needed guidance on the accuracy of survey-based diabetes typing algorithms.

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