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1.
J Am Chem Soc ; 146(35): 24320-24329, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39163142

RESUMO

How disorder affects magnetic ordering is always an intriguing question, and it becomes even more interesting in the recently rising high entropy oxides due to the extremely high disorder density. However, due to the lack of high-quality single crystal samples, the strong compositional disorder effect on magnetic transition has not been deeply investigated. In this work, we have successfully synthesized high-quality single crystalline high entropy spinel ferrites (Mg0.2Mn0.2Fe0.2Co0.2Ni0.2)xFe3-xO4. Our findings from high-temperature magnetization and neutron diffraction experiments showed ferrimagnetic transitions at 748, 694, and 674 K for x values of 1, 1.5, and 1.8, respectively. Notably, the magnetic transition almost showed no broadening for x values of 1 and 1.5, compared to Fe3O4. Extended X-ray absorption fine structure measurements provided insights into the elemental distribution among the octahedral and tetrahedral sites. The random distribution of elements across these sites reduced the formation of local clusters and short-range orders, enhancing sample homogeneity and preserving the sharpness of the magnetic transition, despite bond length variation. Our study not only marks the first successful synthesis of an HEO bulk single crystal exhibiting long-range magnetic order but also sheds light on the interaction between high configurational entropy and magnetic orderings. This opens new avenues for future research and applications of magnetic high entropy oxides.

2.
Malar J ; 23(1): 28, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38243243

RESUMO

BACKGROUND: In children with cerebral malaria (CM) admission blood lactate has previously guided intravenous fluid therapy and been validated as a prognostic biomarker associated with death. The usefulness of post-admission measurements of blood lactate in children with CM is less clear. The strength of association between blood lactate and neurological sequelae in CM survivors, as well as the optimal duration of post-admission measurements of blood lactate to identify children at higher risk of adverse outcomes is unknown. METHODS: A retrospective cohort study of 1674 Malawian children with CM hospitalized from 2000 to 2018 who had blood lactate measurements every 6 h for the first 24 h after admission was performed. The strength of association between admission lactate or values measured at any time point in the first 24 h post-admission and outcomes (mortality and neurological morbidity in survivors) was estimated. The duration of time after admission that lactate remained a valid prognostic biomarker was assessed. RESULTS: When lactate is analysed as a continuous variable, children with CM who have higher values at admission have a 1.05-fold higher odds (95% CI 0.99-1.11) of death compared to those with lower lactate values. Children with higher blood lactate at 6 h have 1.16-fold higher odds (95% CI 1.09-1.23) of death, compared to those with lower values. If lactate levels are dichotomized into hyperlactataemic (lactate > 5.0 mmol/L) or not, the strength of association between admission lactate and mortality increases (OR = 2.49, 95% CI 1.47-4.22). Blood lactate levels obtained after 18 h post-admission are not associated with outcomes. Similarly, the change in lactate concentrations through time during the first 24 h of hospital admission is not associated with outcomes. Blood lactate during hospitalization is not associated with adverse neurologic outcomes in CM survivors. CONCLUSIONS: In children with CM, blood lactate is associated with death but not neurologic morbidity in survivors. To comprehensively estimate prognosis, blood lactate in children with CM should be assessed at admission and for 18 h afterwards.


Assuntos
Malária Cerebral , Criança , Humanos , Malária Cerebral/complicações , Estudos Retrospectivos , Ácido Láctico , Morbidade , Biomarcadores , Hospitais
3.
J Allergy Clin Immunol ; 152(1): 266-277, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36841265

RESUMO

BACKGROUND: Severe congenital neutropenia presents with recurrent infections early in life as a result of arrested granulopoiesis. Multiple genetic defects are known to block granulocyte differentiation; however, a genetic cause remains unknown in approximately 40% of cases. OBJECTIVE: We aimed to characterize a patient with severe congenital neutropenia and syndromic features without a genetic diagnosis. METHODS: Whole exome sequencing results were validated using flow cytometry, Western blotting, coimmunoprecipitation, quantitative PCR, cell cycle and proliferation analysis of lymphocytes and fibroblasts and granulocytic differentiation of primary CD34+ and HL-60 cells. RESULTS: We identified a homozygous missense mutation in DBF4 in a patient with mild extra-uterine growth retardation, facial dysmorphism and severe congenital neutropenia. DBF4 is the regulatory subunit of the CDC7 kinase, together known as DBF4-dependent kinase (DDK), the complex essential for DNA replication initiation. The DBF4 variant demonstrated impaired ability to bind CDC7, resulting in decreased DDK-mediated phosphorylation, defective S-phase entry and progression and impaired differentiation of granulocytes associated with activation of the p53-p21 pathway. The introduction of wild-type DBF4 into patient CD34+ cells rescued the promyelocyte differentiation arrest. CONCLUSION: Hypomorphic DBF4 mutation causes autosomal-recessive severe congenital neutropenia with syndromic features.


Assuntos
Proteínas de Ciclo Celular , Proteínas de Saccharomyces cerevisiae , Humanos , Proteínas de Ciclo Celular/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Mutação , Fosforilação
4.
Mol Genet Metab ; 140(3): 107696, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37690181

RESUMO

PURPOSE: Individuals with urea cycle disorders (UCDs) may develop recurrent hyperammonemia, episodic encephalopathy, and neurological sequelae which can impact Health-related Quality of Life (HRQoL). To date, there have been no systematic studies of HRQoL in people with UCDs. METHODS: We reviewed HRQoL and clinical data for 190 children and 203 adults enrolled in a multicenter UCD natural history study. Physical and psychosocial HRQoL in people with UCDs were compared to HRQoL in healthy people and people with phenylketonuria (PKU) and diabetes mellitus. We assessed relationships between HRQoL, UCD diagnosis, and disease severity. Finally, we calculated sample sizes required to detect changes in these HRQoL measures. RESULTS: Individuals with UCDs demonstrated worse physical and psychosocial HRQoL than their healthy peers and peers with PKU and diabetes. In children, HRQoL scores did not differ by diagnosis or severity. In adults, individuals with decreased severity had worse psychosocial HRQoL. Finally, we show that a large number of individuals would be required in clinical trials to detect differences in HRQoL in UCDs. CONCLUSION: Individuals with UCDs have worse HRQoL compared to healthy individuals and those with PKU and diabetes. Future work should focus on the impact of liver transplantation and other clinical variables on HRQoL in UCDs.


Assuntos
Diabetes Mellitus , Hiperamonemia , Transplante de Fígado , Fenilcetonúrias , Distúrbios Congênitos do Ciclo da Ureia , Criança , Humanos , Adulto , Qualidade de Vida , Distúrbios Congênitos do Ciclo da Ureia/diagnóstico , Hiperamonemia/diagnóstico , Fenilcetonúrias/complicações , Estudos Multicêntricos como Assunto
5.
BMC Public Health ; 23(1): 1278, 2023 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-37400757

RESUMO

BACKGROUND: Adolescent parents experience worse health and socioeconomic outcomes compared to older parents. Little is known about the factors that can lead to better health and well-being among teen-headed families. A city-wide collaborative conducted a comprehensive well-being assessment of expectant and parenting teens in Washington, DC. METHODS: An online, anonymous survey was conducted with adolescent parents in Washington, DC, using convenience sampling. The survey consisted of 66 questions adapted from validated scales of quality of life and well-being. Descriptive statistics were used to describe the data overall, by subgroups of mother and father, and by subgroups of parent age. Spearman's correlations were utilized to demonstrate associations of social supports with well-being metrics. RESULTS: A total of 107 adolescent and young adult parents from Washington, DC, completed the survey; 80% of respondents identified as mothers and 20% as fathers. Younger adolescent parents rated their physical health better compared to older adolescent and young adult parents. Adolescent parents reported accessing various governmental and community-based resources in the preceding 6 months. The most used resources were supplemental food programs, with 35% receiving Supplemental Nutrition Assistance Program benefits and 24% receiving support from the Special Supplemental Nutrition Program for Women, Infants and Children. There was no significant difference in health-related well-being metrics among those who did and did not receive resources. Having higher self-reported social support was positively correlated with higher self-rated physical health, mental health, and well-being, as well as experiencing positive emotions, and was negatively correlated with experiencing negative emotions. CONCLUSION: This snapshot of the well-being of expectant and parenting teens in Washington, DC, showed overall positive physical, mental, and emotional health. Greater social support was correlated with better outcomes in these areas. Future work will leverage the multidisciplinary collaborative to translate these findings into policies and programs that meet the needs of this population.


Assuntos
Pais , Qualidade de Vida , Criança , Lactente , Adulto Jovem , Humanos , Adolescente , Feminino , District of Columbia , Poder Familiar/psicologia , Apoio Social , Inquéritos e Questionários
6.
BMC Med Educ ; 22(1): 533, 2022 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-35804336

RESUMO

BACKGROUND: Our goal was to improve pediatric residents' advanced communication skills in the setting of referral to address the entrustable professional activity of subspecialty referral identified by the American Board of Pediatrics. To accomplish this aim, we created a referral and consultation curriculum to teach and assess core communication skills in subspecialty referral involving an adolescent with syncope, an anxiety-provoking symptom that is rarely associated with serious pathology. METHODS: We utilized blended multimodal educational interventions to improve resident communication skills in referral of patients. Trainees participated in 1) an interactive online module on syncope focusing on "red-flag" symptoms that would warrant a subspecialty cardiology referral and 2) a 4-h intervention with Standardized Parents (SPs), focusing on the case-based application of communication skills. Communication skills were assessed by two pre- and post- Objective Structured Clinical Examination encounters of patients with syncope, with an SP evaluation using a 20-item checklist. Analysis was performed with Sign test and McNemar's test. Trainees provided feedback on a Critical Incident Questionnaire, which was analyzed qualitatively. RESULTS: Sixty-four residents participated. There was an overall improvement in communication skills based on SP scores (82.7 ± 10.9% to 91.7 ± 5.0%, p < 0.001), and 13/20 items demonstrated significant improvement post-intervention. Residents' improved performance enabled them to address patient/family emotions, explain referral logistics, and clarify concerns to agree on a plan. CONCLUSIONS: By participating in this curriculum, residents' communication skills improved immediately post-intervention. Further research is needed to assess if this intervention improves patient care by providing residents with enduring skills to judiciously manage the referral process.


Assuntos
Internato e Residência , Adolescente , Criança , Competência Clínica , Comunicação , Currículo , Humanos , Encaminhamento e Consulta , Síncope
7.
Blood ; 133(4): 319-330, 2019 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-30333120

RESUMO

Dendritic cells (DCs) are a key cell type in the initiation of the adaptive immune response. Recently, an additional role for DCs in suppressing myeloproliferation was discovered. Myeloproliferative disorder (MPD) was observed in murine studies with constitutive depletion of DCs, as well as in patients with congenital deficiency in DCs caused by mutations in GATA2 or IRF8 The mechanistic link between DC deficiency and MPD was not predicted through the known biology and has remained an enigma. Prevailing models suggest numerical DC deficiency leads to MPD through compensatory myeloid differentiation. Here, we formally tested whether MPD can also arise through a loss of DC function without numerical deficiency. Using mice whose DCs are deficient in antigen presentation, we find spontaneous MPD that is characterized by splenomegaly, neutrophilia, and extramedullary hematopoiesis, despite normal numbers of DCs. Disease development was dependent on loss of the MHC class II (MHCII) antigen-presenting complex on DCs and was eliminated in mice deficient in total lymphocytes. Mice lacking MHCII and CD4 T cells did not develop disease. Thus, MPD was paradoxically contingent on the presence of CD4 T cells and on a failure of DCs to activate CD4 T cells, trapping the cells in a naive Flt3 ligand-expressing state. These results identify a novel requirement for intercellular collaboration between DCs and CD4 T cells to regulate myeloid differentiation. Our findings support a new conceptual framework of DC biology in preventing MPD in mice and humans.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Comunicação Celular , Células Dendríticas/imunologia , Transtornos Mieloproliferativos/imunologia , Animais , Antígeno CD11c/metabolismo , Ativação Linfocitária/imunologia , Camundongos Endogâmicos C57BL , Células Mieloides/patologia , Transtornos Mieloproliferativos/patologia
8.
BJU Int ; 128(3): 366-373, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33765326

RESUMO

OBJECTIVE: To investigate whether bipolar androgen therapy (BAT), involving rapid cyclic administration of high-dose testosterone, as a novel treatment for metastatic castration-resistant prostate cancer (mCRPC) promotes improvements in body composition and associated improvements in lipid profiles and quality of life. PATIENTS AND METHODS: Men from two completed trials with computed tomography imaging at baseline and after three cycles of BAT were included. Cross-sectional areas of psoas muscle, visceral and subcutaneous fat were measured at the L3 vertebral level. Functional Assessment of Chronic Illness Therapy - Fatigue questionnaire and 36-item short-form health survey were used to assess quality of life. RESULTS: The 60 included patients lost a mean (sd) of 7.8 (8.2)% of subcutaneous fat, 9.8 (18.2)% of visceral fat, and gained 12.2 (6.7)% muscle mass. Changes in subcutaneous and visceral fat were positively correlated with each other (Spearman's correlation coefficient 0.58, 95% confidence interval 0.35-0.71) independent of the effects of age, body mass index, and duration of androgen-deprivation therapy. Energy, physical function, and measures of limitations due to physical health were all significantly improved at 3 months. The improvements in body composition were not correlated with decreases in lipid levels or observed improvements in quality of life. CONCLUSIONS: In the present study, BAT was associated with significant improvements in body composition, lipid parameters, and quality of life. This has promising implications for the long-term health of men with mCRPC.


Assuntos
Antagonistas de Androgênios/uso terapêutico , Androgênios/administração & dosagem , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Testosterona/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Composição Corporal , Humanos , Metabolismo dos Lipídeos , Masculino , Pessoa de Meia-Idade , Neoplasias de Próstata Resistentes à Castração/metabolismo , Neoplasias de Próstata Resistentes à Castração/fisiopatologia , Qualidade de Vida
9.
Pediatr Diabetes ; 22(7): 1071-1080, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34369043

RESUMO

OBJECTIVE: The current study explored pre-pandemic sociodemographics, medical characteristics, social/family support, and mood symptoms, and current COVID-19 experiences as predictors of mood, positive/negative diabetes-specific experiences, and COVID-19-specific distress among parents of children with type 1 diabetes during the COVID-19 pandemic. We hypothesized that parents from marginalized backgrounds, youth with higher pre-pandemic A1c and no CGM use, parents with lower pre-pandemic social/family support and more pre-pandemic mood/anxiety symptoms, and those with more negative COVID-19 experiences would have more depressive symptoms, fewer positive and more negative diabetes-specific experiences, and more COVID-19-specific distress during the initial months of the pandemic. RESEARCH DESIGN AND METHODS: Participants were parents of early school-age children with type 1 diabetes (n = 100; 65% non-Hispanic, white, 92% mothers, 75% married; Mchild age  = 6.74 ± 1.59 years) who had completed a behavioral intervention trial ≥6 months ago and were re-contacted in June/July 2020 to report on their COVID-19 pandemic experiences and parent psychosocial outcomes. Pre-pandemic parent mood/anxiety symptoms, family/social support, and children's medical characteristics (CGM use; MA1C  = 8.17% ± 1.40%) were assessed M = 1.45 ± 0.59 years prior. RESULTS: More pre-pandemic social support predicted fewer depressive symptoms, more positive diabetes-specific experiences, and less COVID-19-specific distress during the pandemic. More pre-pandemic depressive symptoms predicted more depressive symptoms during the pandemic. More life disruptions due to the pandemic were associated with more negative diabetes-specific experiences and more COVID-19-specific distress. Parents of color had more negative diabetes-specific experiences. CONCLUSIONS: Social support may be particularly important to assess and address through intervention. Pediatric diabetes care providers should monitor parent experiences in relation to children's diabetes management. ClinicalTrials.gov identifier: NCT02527525.


Assuntos
Ansiedade/psicologia , COVID-19/psicologia , Diabetes Mellitus Tipo 1/psicologia , Pandemias , Pais/psicologia , SARS-CoV-2 , Estresse Psicológico/psicologia , Ansiedade/epidemiologia , Ansiedade/etiologia , COVID-19/complicações , COVID-19/epidemiologia , Criança , Pré-Escolar , Comorbidade , Diabetes Mellitus Tipo 1/epidemiologia , Feminino , Seguimentos , Humanos , Lactente , Masculino , Poder Familiar/psicologia , Estudos Retrospectivos , Instituições Acadêmicas , Apoio Social , Estresse Psicológico/etiologia , Fatores de Tempo , Estados Unidos
10.
J Allergy Clin Immunol ; 146(5): 1180-1193, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32325141

RESUMO

BACKGROUND: The molecular cause of severe congenital neutropenia (SCN) is unknown in 30% to 50% of patients. SEC61A1 encodes the α-subunit of the Sec61 complex, which governs endoplasmic reticulum protein transport and passive calcium leakage. Recently, mutations in SEC61A1 were reported to be pathogenic in common variable immunodeficiency and glomerulocystic kidney disease. OBJECTIVE: Our aim was to expand the spectrum of SEC61A1-mediated disease to include autosomal dominant SCN. METHODS: Whole exome sequencing findings were validated, and reported mutations were compared by Western blotting, Ca2+ flux assays, differentiation of transduced HL-60 cells, in vitro differentiation of primary CD34 cells, quantitative PCR for unfolded protein response (UPR) genes, and single-cell RNA sequencing on whole bone marrow. RESULTS: We identified a novel de novo missense mutation in SEC61A1 (c.A275G;p.Q92R) in a patient with SCN who was born to nonconsanguineous Belgian parents. The mutation results in diminished protein expression, disturbed protein translocation, and an increase in calcium leakage from the endoplasmic reticulum. In vitro differentiation of CD34+ cells recapitulated the patient's clinical arrest in granulopoiesis. The impact of Q92R-Sec61α1 on neutrophil maturation was validated by using HL-60 cells, in which transduction reduced differentiation into CD11b+CD16+ cells. A potential mechanism for this defect is the uncontrolled initiation of the unfolded protein stress response, with single-cell analysis of primary bone marrow revealing perturbed UPR in myeloid precursors and in vitro differentiation of primary CD34+ cells revealing upregulation of CCAAT/enhancer-binding protein homologous protein and immunoglobulin heavy chain binding protein UPR-response genes. CONCLUSION: Specific mutations in SEC61A1 cause SCN through dysregulation of the UPR.


Assuntos
Síndrome Congênita de Insuficiência da Medula Óssea/genética , Mutação/genética , Neutropenia/congênito , Neutrófilos/fisiologia , Canais de Translocação SEC/genética , Antígenos CD34/metabolismo , Transtornos Cromossômicos , Feminino , Genes Dominantes , Células HL-60 , Humanos , Neutropenia/genética , Linhagem , Análise de Célula Única , Resposta a Proteínas não Dobradas/genética , Sequenciamento do Exoma , Adulto Jovem
11.
Prostate ; 80(11): 895-905, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32506665

RESUMO

BACKGROUND: Intraprostatic inflammation is an emerging prostate cancer risk factor. Estrogens are pro-inflammatory while androgens are anti-inflammatory. Thus, we investigated whether serum sex steroid hormone concentrations are associated with intraprostatic inflammation to inform mechanistic links among hormones, inflammation, and prostate cancer. METHODS: We conducted a cross-sectional study among 247 men in the placebo arm of the Prostate Cancer Prevention Trial who had a negative end-of-study biopsy, most (92.7%) performed without clinical indication per trial protocol. Serum estradiol, estrone, and testosterone were previously measured by immunoassay in pooled baseline and Year 3 serum. Free estradiol and free testosterone were calculated. Inflammation was visually assessed (median of three prostate biopsy cores per man). Polytomous or logistic regression was used to estimate the odds ratio (OR) and 95% confidence interval (CI) of some or all cores inflamed (both vs none) or any core inflamed (vs none) by hormone tertile, adjusting for age, race, and family history. We evaluated effect modification by waist circumference and body mass index (BMI). RESULTS: In all, 51.4% had some and 26.3% had all cores inflamed. Free (P-trend = .11) but not total estradiol was suggestively inversely associated with all cores inflamed. In men with waist circumference greater than or equal to 102 cm (P-trend = .021) and BMI ≥ 27.09 kg/m2 (P-trend = .0037) free estradiol was inversely associated with any core inflamed. Estrone was inversely associated with all cores inflamed (T3: OR = 0.36, 95% CI 0.14-0.95, P-trend = .036). Total (T3: OR = 1.91, 95% CI 0.91-4.02, P-trend = .11) and free (T3: OR = 2.19, 95% CI 1.01-4.74, P-trend = .05) testosterone were positively associated with any core inflamed, especially free testosterone in men with waist circumference less than 102 cm (T3: OR = 3.51, 95% CI 1.03-12.11, P-trend = .05). CONCLUSIONS: In this first study in men without prostate cancer and irrespective of clinical indication for biopsy, contrary to the hypothesis, circulating estrogens appeared to be inversely associated, especially in heavy men, whereas androgens appeared to be positively associated with intraprostatic inflammation.


Assuntos
Hormônios Esteroides Gonadais/sangue , Prostatite/sangue , Idoso , Biópsia , Peso Corporal , Estudos Transversais , Humanos , Masculino , Pessoa de Meia-Idade , Placebos , Neoplasias da Próstata/prevenção & controle , Prostatite/patologia , Ensaios Clínicos Controlados Aleatórios como Assunto
12.
Cytogenet Genome Res ; 160(4): 185-192, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32316019

RESUMO

A phenotype is emerging for the proximal pair of G-dark bands in 11q (11q14.1 and q14.3) but not yet for the distal pair (11q22.1 and q22.3). A mother and daughter with the same directly transmitted 12.3-Mb interstitial deletion of 11q21q22.3 (GRCh37: 93,551,765-105,817,723) both had initial feeding difficulties and failure to thrive, speech delay, learning difficulties, and mild dysmorphism. Among 17 patients with overlapping deletions, developmental or speech delay, dysmorphism, hypotonia, intellectual disability or learning difficulties, short stature, and coloboma were each found in 2 or more. These results may provide the basis for a consistent phenotype for this region. Among the 53 deleted and additional breakpoint genes, CNTN5, YAP1, and GRI4 were the most likely candidates. Non-penetrance of haploinsufficient genes and dosage compensation among related genes may account for the normal cognition in the mother and variable phenotypes that can extend into the normal range.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 11/genética , Anormalidades Múltiplas/patologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Contactinas/genética , Feminino , Humanos , Fenótipo , Receptores de AMPA/genética , Fatores de Transcrição/genética , Proteínas de Sinalização YAP
13.
Cancer Causes Control ; 30(4): 343-354, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30825046

RESUMO

PURPOSE: Two prior cohort studies suggested that choline, but not betaine intake, is associated with an increased risk of advanced prostate cancer (PCa). Given that evidence remains limited, we evaluated whether intakes of choline and derivative betaine are associated with total and lethal PCa risk and PCa death in men with PCa. METHODS: We included 6,528 men (24.4% African American) without a cancer diagnosis at baseline (1987-1989) followed through 2012. Dietary intake was assessed using a food frequency questionnaire coupled with a nutrient database. We used Cox proportional hazards regression to estimate hazards ratios (HRs) and 95% confidence intervals (CIs) of total and lethal PCa risk overall and by race. RESULTS: Choline intake was not associated with total (n = 811) or lethal (n = 95) PCa risk overall or by race. Betaine intake was inversely associated with lethal (tertile 3 vs 1, HR 0.59, 95% CI 0.35-1.00, p trend = 0.04), but not total PCa risk; patterns for lethal PCa were similar by race. Neither nutrient was associated with PCa death in men with PCa. CONCLUSIONS: Choline intake was not associated with total or lethal PCa or with PCa death in men with PCa. Betaine intake was inversely associated with lethal, but not total PCa risk or with PCa death in men with PCa. Our results do not support the hypothesis that higher choline intake increases lethal PCa risk, but do suggest that higher betaine intake may be associated with lower lethal PCa risk. Further investigation with a larger number of lethal cases is needed.


Assuntos
Betaína/administração & dosagem , Colina/administração & dosagem , Dieta , Neoplasias da Próstata/epidemiologia , Estudos de Coortes , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Fatores de Risco
14.
Med Educ ; 53(8): 778-787, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31012131

RESUMO

CONTEXT: Globally, primary health care is facing workforce shortages. Longer and higher-quality placements in primary care increase the likelihood of medical students choosing this specialty. However, the recruitment and retention of community primary care teachers are challenging. Relevant research was predominantly carried out in the 1990s. We seek to understand contemporary facilitators and barriers to general practitioner (GP) engagement with undergraduate education. Communities of practice (CoP) theory offers a novel conceptualisation, which may be pertinent in other community-based teaching settings. METHODS: Semi-structured interviews were undertaken with 24 GP teachers at four UK medical schools. We purposively sampled GPs new to teaching, established GP teachers and GPs who had recently stopped teaching. We undertook NVivo-assisted deductive and inductive thematic analysis of transcripts. We used CoP theory to interpret data. RESULTS: Communities of practice theory illustrated that teachers negotiate membership of three CoPs: (i) clinical practice; (ii) the medical school, and (iii) teaching. The delivery of clinical care and teaching may be integrated or exist in tension. This can depend upon the positioning of the teaching and teacher as central or peripheral to the clinical CoP. Remuneration, workload, space and the expansion of GP trainee numbers impact on this. Teachers did not identify strongly as members of the medical school or a teaching community. Perceptions of membership were affected by medical school communication and support. The findings demonstrate gaps in medical school recruitment. CONCLUSIONS: This research demonstrates the marginalisation of primary care-based teaching and proposes a novel explanation rooted in CoP theory. Concepts including identity and membership may be pertinent to other community-based teaching settings. We recommend that medical schools review and broaden recruitment methods. Teacher retention may be improved by optimising the interface between medical schools and teachers, fostering a teaching community, increasing professional rewards for teaching involvement and altering medical school expectations of learning in primary care.


Assuntos
Medicina Geral/educação , Clínicos Gerais/provisão & distribuição , Estudantes de Medicina , Ensino , Educação de Graduação em Medicina , Docentes de Medicina/psicologia , Feminino , Humanos , Entrevistas como Assunto , Masculino , Reino Unido
15.
Mod Pathol ; 31(10): 1539-1552, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29849114

RESUMO

The inflammatory microenvironment plays an important role in the pathogenesis and progression of tumors and may be associated with somatic genomic alterations. We examined the association of tumor-infiltrating T-cell density with clinical-pathologic variables, tumor molecular subtype, and oncologic outcomes in surgically treated primary prostate cancer occurring in patients of European-American or African-American ancestry. We evaluated 312 primary prostate tumors, enriched for patients with African-American ancestry and high grade disease. Tissue microarrays were immunostained for CD3, CD8, and FOXP3 and were previously immunostained for ERG and PTEN using genetically validated protocols. Image analysis for quantification of T-cell density in tissue microarray tumor spots was performed. Automated quantification of T-cell densities in tumor-containing regions of tissue microarray spots and standard histologic sections were correlated (r = 0.73, p < 0.00001) and there was good agreement between visual and automated T-cell density counts on tissue microarray spots (r = 0.93, p < 0.00001). There was a significant correlation between CD3+, CD8+, and FOXP3+ T-cell densities (p < 0.00001), but these were not associated with most clinical or pathologic variables. Increased T-cell density was significantly associated with ERG positivity (median 309 vs. 188 CD3+ T cells/mm2; p = 0.0004) and also with PTEN loss (median 317 vs. 192 CD3+ T cells/mm2; p = 0.001) in the combined cohort of matched European-American and African-American ancestry patients. The same association or a similar trend was present in patients of both ancestries when analyzed separately. When the African-American patients from the matched race set were combined with a separate high grade set of African-American cases, there was a weak association of increased FOXP3+ T-cell densities with increased risk of metastasis in multivariable analysis. Though high T-cell density is associated with specific molecular subclasses of prostate cancer, we did not find an association of T-cell density with racial ancestry.


Assuntos
Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/patologia , Neoplasias da Próstata/etnologia , Neoplasias da Próstata/patologia , Microambiente Tumoral/imunologia , Negro ou Afro-Americano , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/genética , População Branca
16.
Am J Med Genet A ; 176(2): 319-329, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29194955

RESUMO

The direct transmission of microscopically visible unbalanced chromosome abnormalities (UBCAs) is rare and usually has phenotypic consequences. Here we report four families in which a normal phenotype was initially found in one or more family members. Each UBCA was interpreted with regard to overlapping examples and factors previously associated with transmitted imbalances including incidental ascertainment, low gene density, benign copy number variation (CNV) content, and gene relatedness. A 4.56 Mb deletion of 8p23.1-p23.2 was thought to be causal in the affected proband but showed incomplete penetrance in her mother and sibling (Family 1). Incomplete penetrance was also associated with a 10.88 Mb duplication of 13q21.31-q22.1 (Family 3) and dosage insensitivity with a 17.6 Mb deletion of 22pter-q11.21 (Family 4) that were both ascertained at prenatal diagnosis and each found in 4 unaffected family members. The 22pter-q11.21 deletion is part of a region with high benign CNV content and supports the mapping of cat eye syndrome to a 600 kb interval of 22q11.1-q11.21. Low gene densities of less than 2.0 genes/Mb were found in each of these three families but only after segmentally duplicated genes were excluded from the deletions of 8p and 22q. In contrast, gene density was average and variable expressivity associated with a 3.59 Mb duplication of 8p23.1 incidentally ascertained for paternal infertility (Family 2). Our results indicate that a greater degree of direct parental transmission, incomplete penetrance, and variable expression are features of both sub-microscopic CNVs and UBCAs with relatively low gene and high benign CNV content.


Assuntos
Aberrações Cromossômicas , Transtornos Cromossômicos/diagnóstico , Transtornos Cromossômicos/genética , Variações do Número de Cópias de DNA , Expressão Gênica , Penetrância , Adolescente , Adulto , Encéfalo/anormalidades , Encéfalo/diagnóstico por imagem , Criança , Pré-Escolar , Bandeamento Cromossômico , Deleção Cromossômica , Cromossomos Humanos Par 13 , Cromossomos Humanos Par 22 , Cromossomos Humanos Par 8 , Família , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
17.
Phys Chem Chem Phys ; 20(13): 8460-8465, 2018 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-29192298

RESUMO

From quantum chemistry simulations using density functional theory, we obtain the total electronic energy of an eight-atom sulfur chain as its end-to-end distance is extended until S-S bond rupture occurs. We find that a sulfur chain can be extended by about 40% beyond its nominally straight conformation, where it experiences rupture at an end-to-end tension of about 1.5 nN. Using this rupture force as the chain failure limit in an explicit polymer network simulation model (EPnet), we predict the tensile failure stress for sulfur crosslinked (vulcanized) natural rubber. Quantitative agreement with published experimental data for the failure stress is obtained in these simulations if we assume that only about 30% of the sulfur chains produce viable network crosslinks. Surprisingly, we also find that the failure stress of a rubber network does not scale linearly with the chain failure force limit.

18.
Prostate ; 77(4): 412-424, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27868214

RESUMO

BACKGROUND: Mast cells are of interest in prostate cancer because they possess both pro- and anti-tumorigenic properties and are present in the tumor microenvironment. We studied the association of mast cell count and densities with prostate cancer recurrence using tissue microarrays (TMAs) for 462 men who recurred (cases) and 462 controls that were matched to the cases nested in a cohort of radical prostatectomy patients. METHODS: Dual-immunostaining for mast cell tryptase and epithelial cytokeratin-8 and whole slide image analysis were used to assess total mast cell number, mast cell density (mast cell number/tissue area), and mast cell number per epithelial or stromal area in TMA spots containing tumor (up to 4 per man). We used conditional logistic regression to estimate the odds ratio (OR) and 95% confidence interval of recurrence for the mean, minimum, and maximum mast cell parameters in tumor tissue among each man's TMA spots. RESULTS: After taking into account matching factors of age, race, Gleason sum, and pathologic stage, higher minimum mast cell density in the tumor (comparing highest to lowest quartiles: OR = 0.58, 95% CI 0.40-0.86; P-trend = 0.004) was associated with a lower risk of recurrence. Patterns for mast cell number and ratio of mast cell number to epithelial or stromal area were similar to those for mast cell density. CONCLUSIONS: Our results suggest that intratumoral mast cells may be protective against prostate cancer recurrence and could potentially serve as a prognostic biomarker after prostatectomy. Prostate 77: 412-424, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Mastócitos/fisiologia , Recidiva Local de Neoplasia/patologia , Neoplasias da Próstata/patologia , Estudos de Casos e Controles , Contagem de Células/métodos , Humanos , Masculino , Recidiva Local de Neoplasia/prevenção & controle , Neoplasias da Próstata/prevenção & controle , Fatores de Risco
19.
N Engl J Med ; 370(10): 911-20, 2014 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-24552284

RESUMO

BACKGROUND: We observed a syndrome of intermittent fevers, early-onset lacunar strokes and other neurovascular manifestations, livedoid rash, hepatosplenomegaly, and systemic vasculopathy in three unrelated patients. We suspected a genetic cause because the disorder presented in early childhood. METHODS: We performed whole-exome sequencing in the initial three patients and their unaffected parents and candidate-gene sequencing in three patients with a similar phenotype, as well as two young siblings with polyarteritis nodosa and one patient with small-vessel vasculitis. Enzyme assays, immunoblotting, immunohistochemical testing, flow cytometry, and cytokine profiling were performed on samples from the patients. To study protein function, we used morpholino-mediated knockdowns in zebrafish and short hairpin RNA knockdowns in U937 cells cultured with human dermal endothelial cells. RESULTS: All nine patients carried recessively inherited mutations in CECR1 (cat eye syndrome chromosome region, candidate 1), encoding adenosine deaminase 2 (ADA2), that were predicted to be deleterious; these mutations were rare or absent in healthy controls. Six patients were compound heterozygous for eight CECR1 mutations, whereas the three patients with polyarteritis nodosa or small-vessel vasculitis were homozygous for the p.Gly47Arg mutation. Patients had a marked reduction in the levels of ADA2 and ADA2-specific enzyme activity in the blood. Skin, liver, and brain biopsies revealed vasculopathic changes characterized by compromised endothelial integrity, endothelial cellular activation, and inflammation. Knockdown of a zebrafish ADA2 homologue caused intracranial hemorrhages and neutropenia - phenotypes that were prevented by coinjection with nonmutated (but not with mutated) human CECR1. Monocytes from patients induced damage in cocultured endothelial-cell layers. CONCLUSIONS: Loss-of-function mutations in CECR1 were associated with a spectrum of vascular and inflammatory phenotypes, ranging from early-onset recurrent stroke to systemic vasculopathy or vasculitis. (Funded by the National Institutes of Health Intramural Research Programs and others.).


Assuntos
Adenosina Desaminase/deficiência , Adenosina Desaminase/genética , Peptídeos e Proteínas de Sinalização Intercelular/deficiência , Peptídeos e Proteínas de Sinalização Intercelular/genética , Mutação , Acidente Vascular Cerebral/genética , Doenças Vasculares/genética , Idade de Início , Animais , Modelos Animais de Doenças , Endotélio Vascular/patologia , Feminino , Febre/genética , Humanos , Masculino , Linhagem , Poliarterite Nodosa/genética , Análise de Sequência de DNA , Pele/patologia , Vasculite/genética , Vasculite/patologia , Peixe-Zebra
20.
BMC Cancer ; 17(1): 32, 2017 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-28061773

RESUMO

BACKGROUND: The quantitative analysis of microRNA (miRNA) gene expression in archived formalin-fixed, paraffin embedded (FFPE) tissues has been instrumental to identifying their potential roles in cancer biology, diagnosis, and prognosis. However, it remains unclear whether miRNAs remain stable in FFPE tissues stored for long periods of time. METHODS: Here we report Taqman real-time RT-PCR quantification of miR-21, miR-141, miR-221, and RNU6B small nuclear RNA (snRNA) levels from 92 radical prostatectomy specimens stored for 12-20 years in FFPE blocks. The relative stability of each transcript over time was assessed using general linear models. The correlation between transcript quantities, sample age, and RNA integrity number (RIN) were determined utilizing Spearman rank correlation. RESULTS: All transcript levels linearly decreased with sample age, demonstrating a clear loss of miRNA stability and RNU6B snRNA stability over time. The most rapid rates of degradation were observed for RNU6B and miR-21, while miR-141 and miR-221 were more stable. RNA quality was not correlated with sample age or with miR-21, miR-221, or RNU6B snRNA levels. Conversely, miR-141 levels increased with RNA quality. CONCLUSIONS: MiRNA and snRNA levels gradually decreased over an eight year period in FFPE tissue blocks. Sample age was the most consistent feature associated with miRNA stability. The reference snRNA, RUN6B, was more rapidly degraded when compared to miR-141 and miR-221 miRNAs. Various miRNAs demonstrated differential rates of degradation. Quantitative miRNA studies from long-term archived FFPE tissues may therefore benefit from epidemiologic study design or statistical analysis methods that take into account differential storage-dependent transcript degradation.


Assuntos
MicroRNAs/análise , Inclusão em Parafina/métodos , Neoplasias da Próstata/metabolismo , RNA Nuclear Pequeno/análise , Reação em Cadeia da Polimerase em Tempo Real/métodos , Fixação de Tecidos/métodos , Formaldeído , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , MicroRNAs/genética , RNA Nuclear Pequeno/genética , Fatores de Tempo
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