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Tumors represent ecosystems where subclones compete during tumor growth. While extensively investigated, a comprehensive picture of the interplay of clonal lineages during dissemination is still lacking. Using patient-derived pancreatic cancer cells, we created orthotopically implanted clonal replica tumors to trace clonal dynamics of unperturbed tumor expansion and dissemination. This model revealed the multifaceted nature of tumor growth, with rapid changes in clonal fitness leading to continuous reshuffling of tumor architecture and alternating clonal dominance as a distinct feature of cancer growth. Regarding dissemination, a large fraction of tumor lineages could be found at secondary sites each having distinctive organ growth patterns as well as numerous undescribed behaviors such as abortive colonization. Paired analysis of primary and secondary sites revealed fitness as major contributor to dissemination. From the analysis of pro- and nonmetastatic isogenic subclones, we identified a transcriptomic signature able to identify metastatic cells in human tumors and predict patients' survival.
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Ecosistema , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Perfilación de la Expresión Génica , TranscriptomaRESUMEN
INTRODUCTION: Among children who suffer from acute recurrent pancreatitis (ARP) or chronic pancreatitis (CP), acute pancreatitis (AP) episodes are painful, often require hospitalization, and contribute to disease complications and progression. Despite this recognition, there are currently no interventions to prevent AP episodes. In this retrospective cohort study, we assessed the impact of pancreatic enzyme therapy (PERT) use on clinical outcomes among children with pancreatic-sufficient ARP or CP. METHODS: Children with pancreatic-sufficient ARP or CP in the INSPPIRE-2 cohort were included. Clinical outcomes were compared for those receiving vs not receiving PERT, as well as frequency of AP before and after PERT. Logistic regression was used to study the association between development of AP episodes after starting PERT and response predictors. RESULTS: Among 356 pancreatic-sufficient participants, 270 (76%) had ARP, and 60 (17%) received PERT. Among those on PERT, 42% did not have a subsequent AP episode, during a mean 2.1 years of follow-up. Children with a SPINK1 mutation ( P = 0.005) and those with ARP (compared with CP, P = 0.008) were less likely to have an AP episode after starting PERT. After initiation of PERT, the mean AP annual incidence rate decreased from 3.14 down to 0.71 ( P < 0.001). DISCUSSION: In a retrospective analysis, use of PERT was associated with a reduction in the incidence rate of AP among children with pancreatic-sufficient ARP or CP. These results support the need for a clinical trial to evaluate the efficacy of PERT to improve clinical outcomes among children with ARP or CP.
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BACKGROUND/OBJECTIVES: Bone health of children with acute recurrent pancreatitis (ARP) and chronic pancreatitis (CP) is not well studied. METHODS: This retrospective study was performed at three sites and included data from INSPPIRE-2. RESULTS: Of the 87 children in the study: 46 had ARP (53%), 41 had CP (47%). Mean age was 13.6 ± 3.9 years at last DXA scan. The prevalence of low height-for-age (Z-score < -2) (13%, 10/78) and low bone mineral density (BMD) adjusted for height (Z-score < -2) (6.4%, 5/78) were higher than a healthy reference sample (2.5%, p < 0.0001 and p = 0.03, respectively). CONCLUSION: Children with ARP or CP have lower height and BMD than healthy peers. Attention to deficits in growth and bone mineral accrual in children with pancreatic disease is warranted.
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Densidad Ósea , Pancreatitis Crónica , Humanos , Niño , Adolescente , Estudios Transversales , Estudios Retrospectivos , Pancreatitis Crónica/complicaciones , Pancreatitis Crónica/epidemiologíaRESUMEN
OBJECTIVES: Drug-associated acute pancreatitis (DAP) studies typically focus on single acute pancreatitis (AP) cases. We aimed to analyze the (1) characteristics, (2) co-risk factors, and (3) reliability of the Naranjo scoring system for DAP using INSPPIRE-2 (the INternational Study group of Pediatric Pancreatitis: In search for a cuRE-2) cohort study of acute recurrent pancreatitis (ARP) and chronic pancreatitis (CP) in children. METHODS: Data were obtained from ARP group with ≥1 episode of DAP and CP group with medication exposure ± DAP. Physicians could report multiple risk factors. Pancreatitis associated with Medication (Med) (ARP+CP) was compared to Non-Medication cases, and ARP-Med vs CP-Med groups. Naranjo score was calculated for each DAP episode. RESULTS: Of 726 children, 392 had ARP and 334 had CP; 51 children (39 ARP and 12 CP) had ≥1 AP associated with a medication; 61% had ≥1 AP without concurrent medication exposure. The Med group had other risk factors present (where tested): 10 of 35 (28.6%) genetic, 1 of 48 (2.1%) autoimmune pancreatitis, 13 of 51 (25.5%) immune-mediated conditions, 11 of 50 (22.0%) obstructive/anatomic, and 28 of 51 (54.9%) systemic risk factors. In Med group, 24 of 51 (47%) had involvement of >1 medication, simultaneously or over different AP episodes. There were 20 ARP and 4 CP cases in "probable" category and 19 ARP and 7 CP in "possible" category by Naranjo scores. CONCLUSIONS: Medications were involved in 51 of 726 (7%) of ARP or CP patients in INSPPIRE-2 cohort; other pancreatitis risk factors were present in most, suggesting a potential additive role of different risks. The Naranjo scoring system failed to identify any cases as "definitive," raising questions about its reliability for DAP.
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Pancreatitis Crónica , Humanos , Niño , Enfermedad Aguda , Estudios de Cohortes , Reproducibilidad de los Resultados , Pancreatitis Crónica/etiología , Factores de Riesgo , RecurrenciaRESUMEN
PURPOSE: Pancreatogenic diabetes refers to diabetes mellitus (DM) that develops in the setting of a disease of the exocrine pancreas, including pancreatic ductal adenocarcinoma (PDAC) and chronic pancreatitis (CP). We sought to evaluate whether a blunted nutrient response of pancreatic polypeptide (PP) can differentiate these DM subtypes from type 2 DM (T2DM). METHODS: Subjects with new-onset DM (<3 years' duration) in the setting of PDAC (PDAC-DM, n = 28), CP (CP-DM, n = 38), or T2DM (n = 99) completed a standardized mixed meal tolerance test, then serum PP concentrations were subsequently measured at a central laboratory. Two-way comparisons of PP concentrations between groups were performed using Wilcoxon rank-sum test and analysis of covariance while adjusting for age, sex, and body mass index. RESULTS: The fasting PP concentration was lower in both the PDAC-DM and CP-DM groups than in the T2DM group (P = 0.03 and <0.01, respectively). The fold change in PP at 15 minutes following meal stimulation was significantly lower in the PDAC-DM (median, 1.869) and CP-DM (1.813) groups compared with T2DM (3.283; P < 0.01 for both comparisons). The area under the curve of PP concentration was significantly lower in both the PDAC-DM and CP-DM groups than in T2DM regardless of the interval used for calculation and remained significant after adjustments. CONCLUSIONS: Fasting PP concentrations and the response to meal stimulation are reduced in new-onset DM associated with PDAC or CP compared with T2DM. These findings support further investigations into the use of PP concentrations to characterize pancreatogenic DM and to understand the pathophysiological role in exocrine pancreatic diseases (NCT03460769).
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Carcinoma Ductal Pancreático , Diabetes Mellitus Tipo 2 , Neoplasias Pancreáticas , Pancreatitis Crónica , Humanos , Polipéptido Pancreático , Neoplasias Pancreáticas/complicaciones , Pancreatitis Crónica/complicaciones , Carcinoma Ductal Pancreático/complicaciones , Neoplasias PancreáticasRESUMEN
Low-molecular-weight cyclin E (LMW-E) is an N-terminus deleted (40 amino acid) form of cyclin E detected in breast cancer, but not in normal cells or tissues. LMW-E overexpression predicts poor survival in breast cancer patients independent of tumor proliferation rate, but the oncogenic mechanism of LMW-E and its unique function(s) independent of full-length cyclin E (FL-cycE) remain unclear. In the current study, we found LMW-E was associated with genomic instability in early-stage breast tumors (n = 725) and promoted genomic instability in human mammary epithelial cells (hMECs). Mechanistically, FL-cycE overexpression inhibited the proliferation of hMECs by replication stress and DNA damage accumulation, but LMW-E facilitated replication stress tolerance by upregulating DNA replication and damage repair. Specifically, LMW-E interacted with chromatin and upregulated the loading of minichromosome maintenance complex proteins (MCMs) in a CDC6 dependent manner and promoted DNA repair in a RAD51- and C17orf53-dependent manner. Targeting the ATR-CHK1-RAD51 pathway with ATR inhibitor (ceralasertib), CHK1 inhibitor (rabusertib), or RAD51 inhibitor (B02) significantly decreased the viability of LMW-E-overexpressing hMECs and breast cancer cells. Collectively, our findings delineate a novel role for LMW-E in tumorigenesis mediated by replication stress tolerance and genomic instability, providing novel therapeutic strategies for LMW-E-overexpressing breast cancers.
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Neoplasias de la Mama , Ciclina E , Humanos , Femenino , Ciclina E/genética , Ciclina E/metabolismo , Neoplasias de la Mama/patología , Quinasa 2 Dependiente de la Ciclina/genética , Biomarcadores de Tumor/metabolismo , Inestabilidad Genómica , Inhibidores de Proteínas Quinasas/farmacología , Replicación del ADN/genética , Daño del ADN/genética , Reparación del ADN/genéticaRESUMEN
OBJECTIVES: The objective of this study is to investigate risk factors and disease burden in pediatric acute recurrent pancreatitis (ARP) and chronic pancreatitis (CP). METHODS: Data were obtained from INternational Study group of Pediatric Pancreatitis: In search for a cuRE-2 (INSPPIRE-2), the largest multi-center prospective cohort study in pediatric patients with ARP or CP. RESULTS: Of 689 children, 365 had ARP (53%), 324 had CP (47%). CP was more commonly associated with female sex, younger age at first acute pancreatitis (AP) attack, Asian race, family history of CP, lower BMI%, genetic and obstructive factors, PRSS1 mutations and pancreas divisum. CFTR mutations, toxic-metabolic factors, medication use, hypertriglyceridemia, Crohn disease were more common in children with ARP. Constant or frequent abdominal pain, emergency room (ER) visits, hospitalizations, medical, endoscopic or surgical therapies were significantly more common in CP, episodic pain in ARP. A total of 33.1% of children with CP had exocrine pancreatic insufficiency (EPI), 8.7% had diabetes mellitus. Compared to boys, girls were more likely to report pain impacting socialization and school, medical therapies, cholecystectomy, but no increased opioid use. There was no difference in race, ethnicity, age at first AP episode, age at CP diagnosis, duration of disease, risk factors, prevalence of EPI or diabetes between boys and girls. Multivariate analysis revealed that family history of CP, constant pain, obstructive risk factors were predictors of CP. CONCLUSIONS: Children with family history of CP, constant pain, or obstructive risk factors should raise suspicion for CP.
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Insuficiencia Pancreática Exocrina , Pancreatitis Crónica , Masculino , Niño , Humanos , Femenino , Enfermedad Aguda , Estudios Prospectivos , Recurrencia , Pancreatitis Crónica/complicaciones , Pancreatitis Crónica/epidemiología , Factores de Riesgo , Costo de Enfermedad , Insuficiencia Pancreática Exocrina/complicaciones , Dolor Abdominal/etiología , Dolor Abdominal/complicacionesRESUMEN
OBJECTIVES: Abdominal pain, emergency department visits, and hospitalizations impact lives of children with acute recurrent pancreatitis (ARP) and chronic pancreatitis (CP). Data on health-related quality of life (HRQOL) in this population, however, remains limited. We aimed to evaluate HRQOL in children with ARP or CP; and test biopsychosocial risk factors associated with low HRQOL. METHODS: Data were acquired from the INternational Study Group of Pediatric Pancreatitis: In search for a cuRE registry. Baseline demographic and clinical questionnaires, the Child Health Questionnaire (measures HRQOL) and Child Behavior Checklist (measures emotional and behavioral functioning) were completed at enrollment. RESULTS: The sample included 368 children (54.3% girls, mean ageâ=â12.7years, standard deviation [SD]â=â3.3); 65.2% had ARP and 34.8% with CP. Low physical HRQOL (Mâ=â38.5, SDâ=â16.0) was demonstrated while psychosocial HRQOL (Mâ=â49.5, SDâ=â10.2) was in the normative range. Multivariate regression analysis revealed that clinical levels of emotional and behavioral problems (Bâ=â-10.28, Pâ <â0.001), episodic and constant abdominal pain (Bâ=â04.66, Pâ=â0.03; Bâ=â-13.25, Pâ<â0.001) were associated with low physical HRQOL, after accounting for ARP/CP status, age, sex, exocrine, and endocrine disease (F [9, 271]â=â8.34, Pâ<â0.001). Borderline and clinical levels of emotional and behavioral problems (Bâ=â-10.18, Pâ<â0.001; Bâ=â-15.98, Pâ<â0.001), and constant pain (Bâ=â-4.46, Pâ<â0.001) were associated with low psychosocial HRQOL (F [9, 271]â=â17.18, Pâ<â0.001). CONCLUSIONS: Findings highlight the importance of assessing HRQOL and treating pain and psychosocial problems in this vulnerable group of children.
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Pancreatitis Crónica , Calidad de Vida , Dolor Abdominal/complicaciones , Niño , Femenino , Humanos , Masculino , Pancreatitis Crónica/complicaciones , Pancreatitis Crónica/terapia , Recurrencia , Factores de RiesgoRESUMEN
Outcomes of treatments for patients with breast cancer brain metastasis (BCBM) remain suboptimal, especially for systemic therapy. To evaluate the effectiveness of systemic and local therapy (surgery [S], stereotactic radiosurgery [SRS] and whole brain radiotherapy [WBRT]) in BCBM patients, we analyzed the data of 873 BCBM patients from 1999 to 2012. The median overall survival (OS) and time to progression in the brain (TTP-b) after diagnosis of brain metastases (BM) were 9.1 and 7.1 months, respectively. WBRT prolonged OS in patients with multiple BM (hazard ratio [HR], 0.68; 95% CI, 0.52-0.88; P = .004). SRS alone, and surgery or SRS followed by WBRT (S/SRS + WBRT), were equivalent in OS and TTP-b (median OS, 14.9 vs 17.2 months; median TTP-b, 8.2 vs 8.6 months). Continued chemotherapy prolonged OS (HR, 0.35; 95% CI, 0.30-0.41; P < .001) and TTP-b (HR, 0.48; 95% CI, 0.33-0.70; P < .001), however, with no advantage of capecitabine over other chemotherapy agents used (median OS, 11.8 vs 12.4 months; median TTP-b, 7.2 vs 7.4 months). Patients receiving trastuzumab at diagnosis of BM, continuation of anti-HER2 therapy increased OS (HR, 0.53; 95% CI, 0.34-0.83; P = .005) and TTP-b (HR, 0.41; 95% CI, 0.23-0.74; P = .003); no additional benefit was seen with switching over between trastuzumab and lapatinib (median OS, 18.4 vs 22.7 months; median TTP-b: 7.4 vs 8.7 months). In conclusion, SRS or S/SRS + WBRT were equivalent for patients' OS and local control. Continuation systemic chemotherapy including anti-HER2 therapy improved OS and TTP-b with no demonstrable advantage of capecitabine and lapatinib over other agents of physicians' choice was observed.
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Neoplasias Encefálicas/terapia , Neoplasias de la Mama/terapia , Evaluación de Resultado en la Atención de Salud/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Encefálicas/secundario , Neoplasias de la Mama/patología , Femenino , Hospitales Universitarios , Humanos , Estimación de Kaplan-Meier , Oncología Médica/métodos , Oncología Médica/estadística & datos numéricos , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud/métodos , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , TexasRESUMEN
Elevated serum lactate dehydrogenase (sLDH) is associated with poor clinical outcomes in patients with stage IV metastatic melanoma (MM). It is currently unknown if sLDH elevation correlates with distinct molecular, metabolic, or immune features of melanoma metastases. The identification of such features may identify rational therapeutic strategies for patients with elevated sLDH. Thus, we obtained sLDH levels for melanoma patients with metastases who had undergone molecular and/or immune profiling. Our analysis of multi-omics data from independent cohorts of melanoma metastases showed that elevated sLDH was not significantly associated with differences in immune cell infiltrate, point mutations, DNA copy number variations, promoter methylation, RNA expression, or protein expression in melanoma metastases. The only significant association observed for elevated sLDH was with the number of metastatic sites of disease. Our data support that sLDH correlates with disease burden, but not specific molecular or immunological phenotypes, in metastatic melanoma.
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Biomarcadores de Tumor/sangre , L-Lactato Deshidrogenasa/sangre , Melanoma/sangre , Neoplasias Cutáneas/sangre , Biomarcadores de Tumor/genética , Bases de Datos de Ácidos Nucleicos , Perfilación de la Expresión Génica , Humanos , Inmunohistoquímica , Melanoma/genética , Melanoma/inmunología , Melanoma/secundario , Pronóstico , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/inmunología , Neoplasias Cutáneas/patología , Análisis de Matrices Tisulares , Regulación hacia ArribaRESUMEN
Background: Recent clinical guidelines for adults with neurological disabilities suggest the need to assess measures of static and dynamic balance using the Berg Balance Scale (BBS) and Dynamic Gait Index (DGI) as core outcome measures. Given that the BBS measures both static and dynamic balance, it was unclear as to whether either of these instruments was superior in terms of its convergent and concurrent validity, and whether there was value in complementing the BBS with the DGI. Objective: The objective was to evaluate the concurrent and convergent validity of the BBS and DGI by comparing the performance of these two functional balance tests in people with multiple sclerosis (MS). Methods: Baseline cross-sectional data on 75 people with MS were collected for use in this study from 14 physical therapy clinics participating in a large pragmatic cluster-randomized trial. Convergent validity estimates between the DGI and BBS were examined by comparing the partial Spearman correlations of each test to objective lower extremity functional measures (Timed Up and Go (TUG), Six-Minute Walk Test (6MWT), Timed 25-Foot Walk (T25FW) test) and the self-reported outcomes of physical functioning and general health using the 36-Item Short Form Health Survey (SF-36). Concurrent validity was assessed by applying logistic regression with gait disability as the binary outcome (Patient Determined Disease Steps (PDDS) as the criterion measure). The predictive ability of two models, a reduced/parsimonious model including the BBS only and a second model including both the BBS and DGI, were compared using the adjusted coefficient of determinations. Results: Both the DGI and BBS were strongly correlated with lower extremity measures overall as well as across the two PDSS strata with correlations. In PDDS ≤ 2, the difference in the convergence of BBS with TUG and DGI with TUG was -0.123 (95% CI: -0.280, -0.012). While this finding was statistically significant at a type 1 error rate of 0.05, it was not significant (Hommel's adjusted p-value = 0.465) after accounting for multiple testing corrections to control for the family-wise error rate. The BBSâ»SF-36 physical functioning correlation was at least moderate and significant overall and across both PDDS strata. However, the DGIâ»physical functioning score did not have a statistically significant correlation within PDDS ≤ 2. None of the differences in convergent and concurrent validity between the BBS and DGI were significant. The additional variation in 6MWT explained by the DGI when added to a model with the BBS was 7.78% (95% CI: 0.6%, 15%). Conclusions: These exploratory analyses on data collected in pragmatic real-world settings suggest that neither of these measures of balance is profoundly superior to the other in terms of its concurrent and convergent validity. The DGI may not have any utility for people with PDDS ≤ 2, especially if the focus is on mobility, but may be useful if the goal is to provide insight on lower extremity endurance. Further research leveraging longitudinal data from pragmatic trials and quasi-experimental designs may provide more information about the clinical usefulness of the DGI in terms of its predictive validity when compared to the BBS.
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OBJECTIVE: To investigate the effects of two 12-week exercise training interventions, movement-to-music (M2M) and adapted yoga (AY), on physical and psychosocial outcomes in people with multiple sclerosis (MS). DESIGN: Three-arm randomized controlled proof-of-concept trial. SETTING: A community-based fitness facility. PARTICIPANTS: Participants (N=81) with MS (Patient Determined Disease Steps [PDDS] self-reported disease status scores: 0-6) between ages of 18 and 65 years were randomized to M2M (n=27), AY (n=26), or waitlist control (n=28). INTERVENTIONS: Both M2M and AY completed three 60-minute exercise sessions per week for 12 weeks. Waitlist controls received biweekly newsletters via mail that contained educational information on living with MS. MAIN OUTCOME MEASURES: Primary measures were timed Up and Go (TUG, s) test, 6-minute walk test (6MWT, m), and 5 times sit-to-stand test (FTSST, s). Secondary measures were self-reported outcomes assessed using Patient-Reported Outcomes Measurement Information System Fatigue and Pain Interference Short Form 8a. Participants were evaluated at baseline and postintervention. Primary analyses were performed using an intent-to-treat mixed model analysis of covariance. RESULTS: Comparisons across all 3 groups revealed significant group differences in TUG and 6MWT. Post hoc analyses indicated significant improvements in TUG (least square mean difference [95% confidence interval] = -1.9s [-3.3 to -0.5], P=.01, d=0.7) and 6MWT (41.0m [2.2-80.0], P=.04, d=0.6; controlled for PDDS) in M2M compared to controls, while no significant differences were observed when compared AY to controls. No significant group differences were found in FTSST, fatigue, and pain interference. CONCLUSIONS: M2M may be a useful and enjoyable exercise form for people with MS in improving mobility and walking endurance and merits long-term study in larger study populations.
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Terapia por Ejercicio/métodos , Esclerosis Múltiple/terapia , Musicoterapia/métodos , Música/psicología , Yoga/psicología , Adolescente , Adulto , Anciano , Ejercicio Físico/psicología , Terapia por Ejercicio/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/fisiopatología , Esclerosis Múltiple/psicología , Resistencia Física , Resultado del Tratamiento , Prueba de Paso , Caminata , Adulto JovenRESUMEN
OBJECTIVE: Racial health disparities persist among black and white women for colorectal cancer. Understanding racial differences in the gut microbiota and related covariates (e.g., stress) may yield new insight into unexplained colorectal cancer disparities. METHODS: Healthy non-Hispanic black or white women (age ≥19 years) provided survey data, anthropometrics, and stool samples. Fecal DNA was collected and isolated from a wipe. Polymerase chain reaction was used to amplify the V4 region of the 16SrRNA gene and 250 bases were sequenced using the MiSeq platform. Microbiome data were analyzed using QIIME. Operational taxonomic unit data were log transformed and normalized. Analyses were conducted using linear models in R Package "limma." RESULTS: Fecal samples were analyzed for 80 women (M (SD) age = 39.9 (14.0) years, 47 black, 33 white). Blacks had greater average body mass index (33.3 versus 27.5 kg/m, p < .01) and waist circumference (98.3 versus 86.6 cm, p = .003) than whites. Whites reported more stressful life events (p = .026) and greater distress (p = .052) than blacks. Final models accounted for these differences. There were no significant differences in dietary variables. Unadjusted comparisons revealed no racial differences in alpha diversity. Racial differences were observed in beta diversity and abundance of top 10 operational taxonomic units. Blacks had higher abundances than whites of Faecalibacterium (p = .034) and Bacteroides (p = .038). Stress was associated with abundances of Bifidobacterium. The association between race and Bacteroides (logFC = 1.72, 0 = 0.020) persisted in fully adjusted models. CONCLUSIONS: Racial differences in the gut microbiota were observed including higher Bacteroides among blacks. Efforts to cultivate an "ideal" gut microbiota may help reduce colorectal cancer risk.
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Bacteroides , Bifidobacterium , Faecalibacterium , Microbioma Gastrointestinal , Estrés Psicológico , Circunferencia de la Cintura , Adulto , Femenino , Humanos , Persona de Mediana Edad , Alabama/etnología , Bacteroides/aislamiento & purificación , Bifidobacterium/aislamiento & purificación , Negro o Afroamericano/etnología , Índice de Masa Corporal , Estudios Transversales , Faecalibacterium/aislamiento & purificación , Proyectos Piloto , Estrés Psicológico/etnología , Estrés Psicológico/microbiología , BlancoRESUMEN
Fusobacterium necrophorum (Fn), a gram-negative anaerobe, is increasingly implicated as an etiologic agent in older adolescents and young adults with sore throat. Inadequately treated Fn pharyngitis may result in suppurative complications such as peritonsillar abscess and Lemierre's syndrome. Data from the literature suggest that the incidence of life-threating complications in these age groups from Fn pharyngitis (Lemierre's syndrome) in the United States exceeds those associated with group A beta-hemolytic streptococcal (GAS) pharyngitis (acute rheumatic fever). Using real-time PCR, we previously reported about a 10% prevalence of Fn in asymptomatic medical students and about 20% in students complaining of sore throat at a university student health clinic (p = 0.009). In this study, a comprehensive microbiome analysis of the same study samples confirms that Fn pharyngitis was more common than GAS pharyngitis. Eighteen patients were found to have Fn OTU values exceeding an arbitrary cutoff value of 0.1, i.e. greater than 10% of total sequences, with five subjects reaching values above 0.7. By contrast only 9 patients had GAS OTU values greater than 0.1 and none exceeded 0.6. When the data were analyzed using five separate assessments of alpha diversity, in each case for Fn there were statistically significant differences between Fn positive_high (OTU abundance > 0.1) vs control, Fn positive_high vs Fn negative (OTU abundance = 0), Fn positive_high vs Fn positive_low (OTU abundance > 0 and < 0.1). When the data were analyzed using three beta diversity indexes (Bray-Curtis, weighted unifrac, and unweighted unifrac), there were statistically significant differences between Fn positive_high (OTU abundance ≥ 0.1) vs control for all three. Statistically significant differences remained if we chose somewhat different OTU abundance cutoffs of 0.05 or 0.15. We conclude that Fn appears to play a dominant role in bacterial pharyngitis in the older adolescent and young adult age groups and that the development of a productive mucosal infection with Fn is linked to a significant decrease in the diversity of the associated tonsillar microbiome.