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1.
Res Sq ; 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39372936

RESUMO

Diverse medical and research teams are essential to culturally-responsive care and robust progress of biomedical research. However, structural inequities stymie the entry of trainees from underrepresented in medicine (URiM) backgrounds into the physician-scientist pipeline. The Preparation for Graduate and Medical Education (PARAdiGM) program was designed to provide students from underrepresented backgrounds early exposure to physician-scientist training in the context of ample mentorship and programmatic support. By emphasizing research experience, career exposure, presentation skills, mentorship, and application assistance, PARAdiGM is an incipient experience priming this student group to pursue careers in academic medicine. Since its establishment in 2014, PARAdiGM is already increasing entry of URiM students into the physician-scientist pipeline. Encouragingly, the majority of PARAdiGM alumni have matriculated into US medical schools, of which 16% are currently enrolled in MD-PhD programs. Early outcomes from PARAdiGM suggest that an immersive framework, longitudinal mentoring, and opportunity for self-growth should be incorporated into URiM pipeline programs on a larger scale. In these ways, helping students to envision themselves as members of the physician-scientist community is a step toward breaking down the barriers currently limiting URiM entry into academic medicine.

2.
J Pediatr Gastroenterol Nutr ; 78(3): 634-643, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38284647

RESUMO

OBJECTIVE: Prompt diagnosis of pediatric-onset inflammatory bowel disease (IBD) is crucial for preventing a complicated disease course; however, it is not well understood how social determinants of health might affect pediatric IBD diagnosis. This study examined differences in diagnosis age, biomarkers of disease severity, and anthropometrics with sociodemographic factors in a pediatric IBD cohort. METHODS: Pediatric IBD patients (n = 114) and their parents/caregivers were enrolled from the Children's of Alabama Pediatric IBD Clinic in Birmingham, Alabama. Primary analyses examined associations of child race and ethnicity, parental income, parental education, single-parent household status, insurance type, and distance to a tertiary pediatric gastroenterology referral center with diagnosis age. Secondary analyses examined differences in biomarker levels, height, and body mass index at the time of diagnosis. RESULTS: Racial and ethnic minority children were diagnosed at an older age compared to Non-Hispanic White children (14.4 ± 0.40 vs. 11.7 ± 0.38 years; p < 0.001), and this trend was robust to adjustment with other sociodemographic variables. Parental attainment of a college education attenuated the link between minority race and ethnicity and the likelihood of older age at diagnosis, while other sociodemographic variables had no moderating effect. Racial and ethnic minority children were 5.7 times more likely to have clinically elevated erythrocyte sedimentation rate at diagnosis compared to Non-Hispanic White children (p = .024). CONCLUSIONS: These results suggest that child race and ethnicity may exert a primary effect on the age at diagnosis with pediatric-onset IBD. This study highlights the need for further research on racial and ethnic disparities to promote health equity in pediatric-onset IBD.


Assuntos
Etnicidade , Doenças Inflamatórias Intestinais , Grupos Raciais , Criança , Humanos , Promoção da Saúde , Doenças Inflamatórias Intestinais/diagnóstico , Grupos Minoritários , Alabama , Adolescente
3.
Inflamm Bowel Dis ; 29(6): 960-972, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36661889

RESUMO

BACKGROUND: Early life stress (ELS) is an environmental trigger believed to promote increased risk of IBD. Our goal was to identify mechanisms whereby ELS in mice affects susceptibility to and/or severity of gut inflammation. METHODS: We utilized 2 published animal models of ELS. In the first model, newborn mice were separated from the dam daily for 4 to 8 hours starting on postnatal day 2 and then weaned early on postnatal day 17. Control mice were left undisturbed with the dams until weaning on postnatal day 21. In the second model, dams were fed dexamethasone or vehicle ad libitum in drinking water on postpartum days 1 to 14. Plasma and colonic corticosterone were measured in juvenile and adult mice. Colitis was induced in 4-week-old mice via intraperitoneal injection of interleukin (IL)-10 receptor blocking antibody every 5 days for 15 days. Five or 15 days later, colitis scores and transcripts for Tnf, glucocorticoid receptors, and steroidogenic enzymes were measured. RESULTS: Mice exposed to ELS displayed reduced plasma and colonic corticosterone. Control animals showed improvements in indices of inflammation following cessation of interleukin-10 receptor blockade, whereas ELS-exposed animals maintained high levels of Tnf and histological signs of colitis. In colitic animals, prior exposure to ELS was associated with significantly lower expression of genes associated with corticosterone synthesis and responsiveness. Finally, TNF stimulation of colonic crypt cells from ELS mice led to increased inhibition of corticosterone synthesis. CONCLUSIONS: Our study identifies impaired local glucocorticoid production and responsiveness as a potential mechanism whereby ELS predisposes to chronic colitis in susceptible hosts.


Using 2 distinct animal models, this study shows that in mice, early life stress leads to reduced colonic corticosterone and that induction of colitis after stress removal results in reduced transcription of glucocorticoid synthesis genes, increased Tnf, and enhanced chronicity of intestinal inflammation.


Assuntos
Colite , Estresse Psicológico , Animais , Feminino , Camundongos , Colite/metabolismo , Corticosterona/farmacologia , Modelos Animais de Doenças , Glucocorticoides , Inflamação/etiologia , Estresse Psicológico/complicações
4.
J Clin Transl Sci ; 7(1): e270, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38380392

RESUMO

Introduction: Most students in MD-PhD programs take a leave of absence from medical school to complete PhD training, which promotes a natural loss of clinical skills and knowledge and could negatively impact a student's long-term clinical knowledge. To address this concern, clinical refresher courses in the final year of PhD training have traditionally been used; however, effectiveness of such courses versus a longitudinal clinical course spanning all PhD training years is unclear. Methods: The University of Alabama at Birmingham MD-PhD Program implemented a comprehensive continuing clinical education (CCE) course spanning PhD training years that features three course components: (1) clinical skills; (2) clinical knowledge; and (3) specialty exposure activities. To evaluate course effectiveness, data from an anonymous student survey completed at the end of each semester were analyzed. Results: Five hundred and ninety-seven surveys were completed by MD-PhD students from fall 2014 to 2022. Survey responses indicated that the majority of students found the course helpful to: maintain clinical skills and knowledge (544/597, 91% and 559/597, 94%; respectively), gain exposure to clinical specialties (568/597, 95%), and prepare them for responsibilities during clinical clerkships. During semesters following lockdowns from the COVID-19 pandemic, there were significant drops in students' perceived preparedness. Conclusions: Positive student survey feedback and improved preparedness to return to clinic after development of the course suggests the CCE course is a useful approach to maintain clinical knowledge during research training.

5.
FASEB Bioadv ; 4(10): 648-661, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36238362

RESUMO

Regulatory T cells (Treg) are vital to the maintenance of immune homeostasis. The genetic background of an inbred mouse strain can have a profound effect on the immune response in the animal, including Treg responses. Most Treg studies focus on animals created on the C57BL/6 or BALB/c background. Recent studies have demonstrated a difference in the phenotype and behavior of C57BL/6 and BALB/c Tregs. In this study, we have investigated the function of FVB/N Tregs compared to C57BL/6 and BALB/c. We observed that while FVB/N Tregs appear to suppress normally in a cell contact-dependent system, FVB/N Tregs are less capable of suppressing when regulation depends on the secretion of a soluble factor. FVB/N Tregs produce IL-10; however, TGF-ß was not detected in any culture from C57BL/6 or FVB/N. C57BL/6 Foxp3+ Tregs expressed more of the TGF-ß-related proteins glycoprotein-A repetitions predominant (GARP) and latency-associated peptide (LAP) on the cell surface than both FVB/N and BALB/c, but C57BL/6 Tregs expressed significantly less Ctse (Cathepsin E) mRNA. Each strain displayed different abilities of thymic Tregs (tTreg) to maintain Foxp3 expression and had a varying generation of induced Tregs (iTregs). In vitro generated FVB/N iTregs expressed significantly less GARP and LAP. These results suggest Tregs of different strains have varying phenotypes and dominant mechanisms of action for the suppression of an immune response. This information should be taken into consideration when Tregs are examined in future studies, particularly for therapeutic purposes in a genetically diverse population.

6.
J Clin Transl Sci ; 6(1): e54, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35656336

RESUMO

Background/Objectives: Physician-scientists have long been in high demand owing to their role as key drivers of biomedical innovation, but their dwindling prevalence in research and medical communities threatens ongoing progress. As the principal avenue for physician-scientist development, combined MD-PhD training programs and NIH-funded Medical Scientist Training Programs (MSTPs) must address all aspects of career development, including grant writing skills. Methods: The NIH F-series grants - the F30 grant in particular - model the NIH format of federal funding, and are thus ideal opportunities to acquire biomedical research grant preparation experience. Therefore, in this report, we describe a curricular model through which predoctoral MSTP students obtain exposure to - and training for - F-series grant conceptualization, writing, and evaluation. Results: Since the development of these longitudinal courses, we observed trending improvements in student funding success rates, particularly among original submissions, and perceived benefits among participating students.

7.
J Natl Med Assoc ; 114(3): 251-257, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35232610

RESUMO

Among the many academic challenges faced by dual-degree MD-PhD students is access to professional support networks designed to overcome the unique academic and personal barriers to physician-scientist training. In the current study, we hypothesized that regional access to a student MD-PhD conference, termed the Southeastern Medical Scientist Symposium (SEMSS), would enhance medical and/or graduate training by fostering such relationships between physician-scientist trainees, doing so by discussing both the challenges of physician-scientist training and effective strategies to overcome them. In the current study, we used a mixed-methods approach to evaluate the overall usefulness of SEMSS over a ten-year period (2010-2020) to identify key areas of particular benefit to trainees. The authors used conference registration data to compile self-reported demographic and regional attendance, followed by a post-conference survey to gauge attendee satisfaction. Over the reporting period, SEMSS was attended by equivalent proportions of MD-PhD and undergraduate students, among which were a high-percentage of students from underrepresented minority (URM) groups relative to the national MD-PhD applicant pool; nearly one-third of URM students attendees later matriculated into MD-PhD programs, far exceeding the national MD-PhD matriculation rate. Among the benefits reported by students were "opportunities to network with peers" and opportunities to learn about the physician-scientist career track. Therefore, we therefore propose regional MD-PhD conferences as an effective model to promote diversity within the physician-scientist training pipeline.


Assuntos
Pesquisa Biomédica , Médicos , Escolha da Profissão , Educação de Pós-Graduação em Medicina/métodos , Humanos , Grupos Minoritários , Satisfação Pessoal
8.
Am J Physiol Regul Integr Comp Physiol ; 320(5): R663-R674, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33655759

RESUMO

Exposure to early life stress (ELS) is associated with a greater risk of chronic disease development including depression and cardiovascular disease. Altered gut microbiota has been linked to both depression and cardiovascular disease in mice and humans. Rodent models of early life neglect are used to characterize the mechanistic links between early life stress (ELS) and the risk of disease later in life. However, little is understood about ELS exposure and the gut microbiota in the young mice and the influence of the maternal inheritance of the gut microbiota. We used a mouse model of ELS, maternal separation with early weaning (MSEW), and normally reared mice to determine whether the neonate microbiota is altered, and if so, are the differences attributable to changes in dam microbiota that are then transmitted to their offspring. Individual amplicon sequence variants (ASVs) displayed differential abundance in the microbiota of MSEW compared with normally reared pups at postnatal day (PD) 28. Additionally, ELS exposure reduced the alpha diversity and altered microbial community composition at PD28. The composition, levels of alpha diversity, and abundance of individual ASVs in the microbiota of dams were similar from MSEW or normally reared cohorts. Thus, the observed shifts in the abundance of individual bacterial ASVs in the neonates and young pups are likely driven by endogenous effects of MSEW in the offspring host and are not due to inherited differences from the dam. This knowledge suggests that exposure to ELS has a direct effect on microbial factors on the risk of chronic disease development.


Assuntos
Bactérias/genética , Microbioma Gastrointestinal , Intestinos/microbiologia , Privação Materna , Herança Materna , Estresse Psicológico/microbiologia , Fatores Etários , Animais , Animais Recém-Nascidos , Bactérias/crescimento & desenvolvimento , Comportamento Animal , Modelos Animais de Doenças , Disbiose , Fezes/microbiologia , Feminino , Camundongos Endogâmicos C57BL , Gravidez , Estresse Psicológico/psicologia , Desmame
10.
Am J Clin Pathol ; 151(3): 306-315, 2019 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-30357374

RESUMO

Objectives: To investigate the utilization of CBC and CBC with differential (CBC w/diff) tests at University of Alabama at Birmingham Hospital, and to determine if a reduction in CBC w/diff tests could be achieved without negatively impacting patient care. Methods: The quantity of testing and distribution of repeated tests before, during, and after an educational intervention were compared. Results: CBC w/diff tests were ordered 10-fold more frequently than CBC tests. The trauma burn intensive care unit ordered the most CBC w/diff tests, with repeat tests done every 4 or 12 hours. The educational intervention reduced the number of CBC w/diff tests ordered and tests repeated every 12 hours. Conclusions: The educational intervention changed the ordering practices of CBC w/diff and CBC tests. This was sustained after the intervention and no negative effects on patient care were noted. Similar interventions may lead to optimization of ordering practices of other laboratory tests.


Assuntos
Contagem de Células Sanguíneas/estatística & dados numéricos , Hospitais Universitários/organização & administração , Capacitação em Serviço , Corpo Clínico Hospitalar/educação , Estudos de Coortes , Humanos , Laboratórios Hospitalares , Padrões de Prática Médica , Estudos Retrospectivos , Procedimentos Desnecessários/estatística & dados numéricos
11.
Haematologica ; 104(1): 166-175, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30171022

RESUMO

Immune-mediated thrombotic thrombocytopenic purpura is characterized by severe thrombocytopenia and microangiopathic hemolytic anemia. It is primarily caused by immunoglobin G type autoantibodies against ADAMTS13, a plasma metalloprotease that cleaves von Willebrand factor. However, reliable markers predictive of patient outcomes are yet to be identified. Seventy-three unique patients with a confirmed diagnosis of immune-mediated thrombotic thrombocytopenic purpura between April 2006 and December 2017 were enrolled from the Univeristy of Alabama at Birmingham Medical Center. Clinical information, laboratory values, and a panel of special biomarkers were collected and/or determined. The results demonstrated that the biomarkers associated with endothelial injury (e.g., von Willebrand factor antigen and collagen-binding activity), acute inflammation (e.g., human neutrophil peptides 1-3 and histone/deoxyribonucleic acid complexes), and activation of the complement alternative pathway (e.g., factors Bb and iC3b) were all significantly increased in patients with acute immune-mediated thrombotic thrombocytopenic purpura compared to those in the healthy controls. Moreover, failure to normalize platelet counts within 7 days or failure to markedly reduce serum lactate dehydrogenase by day 5, low total serum protein or albumin, and high serum troponin levels were also predictive of mortality, as were the prolonged activated partial thromboplastin time, high fibrinogen, and elevated serum lactate dehydrogenase, Bb, and sC5b-9 on admission. These results may help to stratify patients for more intensive management. The findings may also provide a framework for future multicenter studies to identify valuable prognostic markers for immune-mediated thrombotic thrombocytopenic purpura.


Assuntos
Autoanticorpos/sangue , Proteínas Sanguíneas/metabolismo , Púrpura Trombocitopênica Trombótica/sangue , Púrpura Trombocitopênica Trombótica/diagnóstico , Adulto , Biomarcadores/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico
12.
Med Sci Educ ; 29(3): 739-747, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32071793

RESUMO

A longstanding challenge facing MD-PhD students and other dual-degree medical trainees is the loss of clinical knowledge that occurs during the non medical phases of training. Academic medical institutions nationwide have developed continued clinical training and exposure to maintain clinical competence; however, quantitative assessment of their usefulness remains largely unexplored. The current study therefore sought to both implement and optimize an online game platform to support MD-PhD students throughout their research training. Sixty three current MD-PhD students completing the PhD research phase of training were enrolled in an institutionally-developed online game platform for 2 preliminary and 4 competition rounds of 3-4 weeks each. During preliminary game rounds, we found that participation, though initially high, declined precipitously throughout the duration of each round, with 37 students participating to some extent. Daily reminders were implemented in subsequent rounds, which markedly improved player participation. Average participation in competition rounds exceeded 35% (23/63) active participants each round, with trending improvement in scores throughout the duration of PhD training. Both player participation and progress through the research phase of the MD-PhD program correlated positively with game performance and therefore knowledge retention and/or acquisition. Coupled with positive survey-based feedback from participants, our data therefore suggest that gamification is an effective tool for MD-PhD programs to combat loss of clinical knowledge during research training.

13.
Acad Pathol ; 5: 2374289518775948, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29888322

RESUMO

There has been a recent recognition of the need to prepare PhD-trained scientists for increasingly diverse careers in academia, industry, and health care. The PhD Data Task Force was formed to better understand the current state of PhD scientists in the clinical laboratory workforce and collect up-to-date information on the training and certification of these laboratorians. In this report, we summarize the findings of the PhD Data Task Force and discuss the relevance of the data collected to the future supply of and demand for PhD clinical laboratory scientists. It is clear that there are multiple career opportunities for PhD scientists in academic medical centers, commercial clinical laboratories, biotechnology and pharmaceutical companies, and the federal government. Certified PhD scientists have and will continue to form an important resource for our technologically advancing field, bringing training in scientific methods, and technologies needed for modern laboratory medicine. The data gathered by the PhD Data Task Force will be of great interest to current and future PhD candidates and graduate PhD scientists as they make decisions regarding future career directions.

14.
Transfusion ; 58(2): 456-460, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29230832

RESUMO

BACKGROUND: Chronic myeloid leukemia (CML) is a common hematologic malignancy; however, its occurrence during pregnancy is unusual due to its low prevalence in females of childbearing age. There are conflicting reports of how to best manage CML in pregnancy, particularly in the setting of leukocytosis. HEMAPHERESIS: A 30-year-old female was diagnosed with CML at 18 weeks' estimated gestational age. On initial presentation she reported fatigue, night sweats, and early satiety, and was found to have a white blood cell (WBC) count of 69.3 × 109 /L and platelet count of 366 × 109 /L. Her disease was managed during pregnancy using interferon-α alone despite persistent leukocytosis. CONCLUSION: CML may be effectively managed during pregnancy, even in the setting of leukocytosis, without the application of leukocytapheresis. Management relies not only upon the coordination of drug therapy and fetal monitoring, but requires close communication between multiple medical disciplines. Leukocytapheresis has been safely performed during pregnancy and may be a suitable adjunct management strategy in pregnant patients diagnosed with CML with specific clinical presentations, such as hyperleukocytosis (WBC count > 150 × 109 /L) and/or symptomatic leukostasis.


Assuntos
Leucaférese , Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , Complicações Neoplásicas na Gravidez/terapia , Adulto , Feminino , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/sangue , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Gravidez , Complicações Neoplásicas na Gravidez/sangue , Complicações Neoplásicas na Gravidez/diagnóstico
15.
Immunity ; 47(6): 1182-1196.e10, 2017 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-29262351

RESUMO

CD4+ T cells are tightly regulated by microbiota in the intestine, but whether intestinal T cells interface with host-derived metabolites is less clear. Here, we show that CD4+ T effector (Teff) cells upregulated the xenobiotic transporter, Mdr1, in the ileum to maintain homeostasis in the presence of bile acids. Whereas wild-type Teff cells upregulated Mdr1 in the ileum, those lacking Mdr1 displayed mucosal dysfunction and induced Crohn's disease-like ileitis following transfer into Rag1-/- hosts. Mdr1 mitigated oxidative stress and enforced homeostasis in Teff cells exposed to conjugated bile acids (CBAs), a class of liver-derived emulsifying agents that actively circulate through the ileal mucosa. Blocking ileal CBA reabsorption in transferred Rag1-/- mice restored Mdr1-deficient Teff cell homeostasis and attenuated ileitis. Further, a subset of ileal Crohn's disease patients displayed MDR1 loss of function. Together, these results suggest that coordinated interaction between mucosal Teff cells and CBAs in the ileum regulate intestinal immune homeostasis.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/imunologia , Ácidos e Sais Biliares/imunologia , Linfócitos T CD4-Positivos/imunologia , Doença de Crohn/imunologia , Ileíte/imunologia , Mucosa Intestinal/imunologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/deficiência , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Acridinas/farmacologia , Adulto , Animais , Ácidos e Sais Biliares/metabolismo , Ácidos e Sais Biliares/farmacologia , Transporte Biológico , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/patologia , Doença de Crohn/genética , Doença de Crohn/patologia , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/imunologia , Homeostase/imunologia , Humanos , Ileíte/genética , Ileíte/patologia , Íleo/imunologia , Íleo/patologia , Imunidade nas Mucosas , Mucosa Intestinal/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Pessoa de Meia-Idade , Estresse Oxidativo , Transdução de Sinais , Tetra-Hidroisoquinolinas/farmacologia
16.
J Investig Med ; 65(5): 942-948, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28270407

RESUMO

Many US medical schools have added a scholarly or research requirement as a potential intervention to increase the number of medical students choosing to become academic physicians and physician scientists. We designed a retrospective qualitative survey study to evaluate the impact of medical school research at the University of Alabama at Birmingham (UAB) on career choices. A survey tool was developed consisting of 74 possible questions with built-in skip patterns to customize the survey to each participant. The survey was administered using the web-based program Qualtrics to UAB School of Medicine alumni graduating between 2000 and 2014. Alumni were contacted 3 times at 2-week intervals during the year 2015, resulting in 168 completed surveys (11.5% response rate). MD/PhD graduates were excluded from the study. Most respondents completed elective research, typically for reasons relating to career advancement. 24 per cent said medical school research increased their desire for research involvement in the future, a response that positively correlated with mentorship level and publication success. Although completion of medical school research was positively correlated with current research involvement, the strongest predictor for a physician scientist career was pre-existing passion for research (p=0.008). In contrast, students motivated primarily by curricular requirement were less likely to pursue additional research opportunities. Positive medical school research experiences were associated with increased postgraduate research in our study. However, we also identified a strong relationship between current research activity and passion for research, which may predate medical school.


Assuntos
Pesquisa Biomédica , Escolha da Profissão , Currículo , Faculdades de Medicina , Alabama , Feminino , Humanos , Masculino , Médicos , Estudos Retrospectivos , Estudantes de Medicina , Inquéritos e Questionários , Resultado do Tratamento , Universidades
17.
J Histochem Cytochem ; 64(12): 753-767, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27798287

RESUMO

The adenomatous polyposis coli (APC) gene is a known tumor suppressor gene, and mice with mutations in Apc (ApcMin/+) spontaneously form multiple intestinal neoplasms. In this model of human colorectal cancer (CRC), it has been reported that CD4+ T-cell-derived interleukin 17 (IL-17) promotes intestinal tumor development, but it is not known if the Apc mutation actually directly alters T-cell function and subsequently tumor immunosurveillance. To investigate the ApcMin/+ mutation on T-cell function, flow cytometric, histochemical, and immunofluorescent studies on both wild-type (Apc+/+) and ApcMin/+ mice were performed. We identified decreased levels of interferon gamma (IFN-γ+)IL-17+ double-positive CD4+ cells in the mesenteric lymph nodes and Peyer's patches of ApcMin/+ mice. In addition, altered levels of CD8+ cells, and changes in CD8+ production of IFN-γ and granzyme B were observed. These T-cell alterations did modify tumor immunosurveillance, as the adoptive transfer of splenocytes from ApcMin/+ animals into a chemically induced CRC model resulted in the inability to prevent epithelial dysplasia. These results suggest an altered T-cell balance in ApcMin/+ mice may disrupt intestinal homeostasis, consequently limiting intestinal tumor immunosurveillance.


Assuntos
Neoplasias Colorretais/imunologia , Linfonodos/patologia , Nódulos Linfáticos Agregados/patologia , Linfócitos T/imunologia , Proteína da Polipose Adenomatosa do Colo/genética , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/patologia , Polaridade Celular , Proliferação de Células , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Granzimas/metabolismo , Interferon gama/metabolismo , Interleucina-17/metabolismo , Mucosa Intestinal/metabolismo , Linfonodos/metabolismo , Mesentério/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Mutação , Nódulos Linfáticos Agregados/metabolismo , Linfócitos T/metabolismo , Linfócitos T/patologia
18.
Haematologica ; 101(11): 1319-1326, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27662014

RESUMO

Acquired thrombotic thrombocytopenic purpura is primarily caused by the deficiency of plasma ADAMTS13 activity resulting from autoantibodies against ADAMTS13. However, ADAMTS13 deficiency alone is often not sufficient to cause acute thrombotic thrombocytopenic purpura. Infections or systemic inflammation may precede acute bursts of the disease, but the underlying mechanisms are not fully understood. Herein, 52 patients with acquired autoimmune thrombotic thrombocytopenic purpura and 30 blood donor controls were recruited for the study. The plasma levels of human neutrophil peptides 1-3 and complement activation fragments (i.e. Bb, iC3b, C4d, and sC5b-9) were determined by enzyme-linked immunosorbent assays. Univariate analyses were performed to determine the correlation between each biomarker and clinical outcomes. We found that the plasma levels of human neutrophil peptides 1-3 and Bb in patients with acute thrombotic thrombocytopenic purpura were significantly higher than those in the control (P<0.0001). The plasma levels of HNP1-3 correlated with the levels of plasma complement fragment Bb (rho=0.48, P=0.0004) and serum lactate dehydrogenase (rho=0.28, P=0.04); in addition, the plasma levels of Bb correlated with iC3b (rho=0.55, P<0.0001), sC5b-9 (rho=0.63, P<0.0001), serum creatinine (rho=0.42, p=0.0011), and lactate dehydrogenase (rho=0.40, P=0.0034), respectively. Moreover, the plasma levels of iC3b and sC5b-9 were correlated (rho=0.72, P<0.0001), despite no statistically significant difference of the two markers between thrombotic thrombocytopenic purpura patients and the control. We conclude that innate immunity, i.e. neutrophil and complement activation via the alternative pathway, may play a role in the pathogenesis of acute autoimmune thrombotic thrombocytopenic purpura, and a therapy targeted at these pathways may be considered in a subset of these patients.


Assuntos
Fator B do Complemento/análise , Púrpura Trombocitopênica Trombótica/imunologia , alfa-Defensinas/sangue , Adulto , Biomarcadores/sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunidade Inata , Masculino , Púrpura Trombocitopênica Trombótica/etiologia , Púrpura Trombocitopênica Trombótica/patologia
19.
South Med J ; 109(9): 588-91, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27598370

RESUMO

OBJECTIVES: Alloantibody formation secondary to transfusion in patients with sickle cell disease (SCD) is a well-known phenomenon. Pretransfusion testing (eg, "antibody screening") protects patients from receiving incompatible red blood cell transfusions. Because alloantibodies have a tendency to evanesce (ie, become undetectable over time), however, this phenomenon puts patients at risk of a delayed hemolytic transfusion reaction or even acute hemolysis. METHODS: We evaluated the records of 71 patients with SCD with alloantibodies detected during a 2-year period to describe their most common specificities and their rate of evanescence. RESULTS: We found that 81% of patients had at least one antibody that was undetectable during the study period; therefore, if patients were transfused with antigen-positive units at a facility that was unaware of their antibody history, life-threatening hemolysis could develop. CONCLUSIONS: Evanescence is a real risk for patients with SCD, and national/regional databases of alloantibodies should be considered a priority.


Assuntos
Bases de Dados Factuais , Eritrócitos/imunologia , Isoanticorpos/imunologia , Adulto , Formação de Anticorpos/imunologia , Transfusão de Sangue/métodos , Feminino , Necessidades e Demandas de Serviços de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Reação Transfusional , Estados Unidos , Adulto Jovem
20.
JCI Insight ; 1(11)2016 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-27525312

RESUMO

Liver fibrosis, a consequence of chronic liver injury and a way station to cirrhosis and hepatocellular carcinoma, lacks effective treatment. Endocannabinoids acting via cannabinoid-1 receptors (CB1R) induce profibrotic gene expression and promote pathologies that predispose to liver fibrosis. CB1R antagonists produce opposite effects, but their therapeutic development was halted due to neuropsychiatric side effects. Inducible nitric oxide synthase (iNOS) also promotes liver fibrosis and its underlying pathologies, but iNOS inhibitors tested to date showed limited therapeutic efficacy in inflammatory diseases. Here, we introduce a peripherally restricted, orally bioavailable CB1R antagonist, which accumulates in liver to release an iNOS inhibitory leaving group. In mouse models of fibrosis induced by CCl4 or bile duct ligation, the hybrid CB1R/iNOS antagonist surpassed the antifibrotic efficacy of the CB1R antagonist rimonabant or the iNOS inhibitor 1400W, without inducing anxiety-like behaviors or CB1R occupancy in the CNS. The hybrid inhibitor also targeted CB1R-independent, iNOS-mediated profibrotic pathways, including increased PDGF, Nlrp3/Asc3, and integrin αvß6 signaling, as judged by its ability to inhibit these pathways in cnr1-/- but not in nos2-/- mice. Additionally, it was able to slow fibrosis progression and to attenuate established fibrosis. Thus, dual-target peripheral CB1R/iNOS antagonists have therapeutic potential in liver fibrosis.

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