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1.
Anal Chem ; 96(37): 14715-14719, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39229957

RESUMEN

Polymer conjugation has risen in importance over the past three decades as a means of increasing the in vivo half-life of biotherapeutics, with benefits including better stability, greater drug efficacy, and lower toxicity. However, the intrinsic variability of polymer synthesis results in products with broad distributions in chain length and branching structure, complicating quality control for successful functionalization and downstream conjugation. Frequently, a combination of several analytical techniques is required for comprehensive characterization. While liquid chromatography-mass spectrometry (LC-MS) is a powerful platform that can provide detailed molecular features of polymers, the mass spectra are inherently challenging to interpret due to high mass polydispersity and overlapping charge distributions. Here, by leveraging Fourier transform-based deconvolution and macromolecular mass defect analysis, we demonstrate a new way to streamline pharmaceutical polymer analysis, shedding light on polymer size, composition, branching, and end-group functionalization with the capability for reaction monitoring.


Asunto(s)
Análisis de Fourier , Espectrometría de Masas , Polímeros , Polímeros/química , Espectrometría de Masas/métodos , Cromatografía Liquida/métodos , Sustancias Macromoleculares/química , Peso Molecular , Cromatografía Líquida con Espectrometría de Masas
2.
BMC Biol ; 21(1): 200, 2023 09 25.
Artículo en Inglés | MEDLINE | ID: mdl-37749565

RESUMEN

BACKGROUND: Lepidoptera (butterflies and moths) is one of the most geographically widespread insect orders in the world, and its species play important and diverse ecological and applied roles. Climate change is one of the biggest challenges to biodiversity this century, and lepidopterans are vulnerable to climate change. Temperature-dependent gene expression differences are of relevance under the ongoing climate crisis. However, little is known about how climate affects gene expression in lepidopterans and the ecological consequences of this, particularly with respect to genes with biased expression in one of the sexes. The common yellow butterfly, Eurema hecabe (Family Pieridae), is one of the most geographically widespread lepidopterans that can be found in Asia, Africa, and Australia. Nevertheless, what temperature-dependent effects there may be and whether the effects differ between the sexes remain largely unexplored. RESULTS: Here, we generated high-quality genomic resources for E. hecabe along with transcriptomes from eight developmental stages. Male and female butterflies were subjected to varying temperatures to assess sex-specific gene expression responses through mRNA and microRNA transcriptomics. We find that there are more temperature-dependent sex-biased genes in females than males, including genes that are involved in a range of biologically important functions, highlighting potential ecological impacts of increased temperatures. Further, by considering available butterfly data on sex-biased gene expression in a comparative genomic framework, we find that the pattern of sex-biased gene expression identified in E. hecabe is highly species-specific, rather than conserved across butterfly species, suggesting that sex-biased gene expression responses to climate change are complex in butterflies. CONCLUSIONS: Our study lays the foundation for further understanding of differential responses to environmental stress in a widespread lepidopteran model and demonstrates the potential complexity of sex-specific responses of lepidopterans to climate change.


Asunto(s)
Mariposas Diurnas , Femenino , Masculino , Animales , Mariposas Diurnas/genética , Temperatura , Genómica , Australia , Biodiversidad
3.
Clin Gastroenterol Hepatol ; 21(10): 2483-2495.e1, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-36731590

RESUMEN

BACKGROUND & AIMS: Several studies have been published on the association between food processing and risks of Crohn's disease (CD) and ulcerative colitis (UC), with some variability in results. We performed a systematic literature review and meta-analysis to study this association. METHODS: From PubMed, Medline, and Embase until October 2022, we identified cohort studies that studied the association between food processing and the risk of CD or UC. Risk of bias of the included studies was assessed by the Newcastle-Ottawa scale. We computed pooled hazard ratios (HRs) and 95% confidence intervals (CIs) using random-effects meta-analysis based on estimates and standard errors. RESULTS: A total of 1,068,425 participants were included (13,594,422 person-years) among 5 cohort studies published between 2020 and 2022. Four of the 5 included studies were scored as high quality. The average age of participants ranged from 43 to 56 years; 55%-83% were female. During follow-up, 916 participants developed CD, and 1934 developed UC. There was an increased risk for development of CD for participants with higher consumption of ultra-processed foods compared with those with lower consumption (HR, 1.71; 95% CI, 1.37-2.14; I2 = 0%) and a lower risk of CD for participants with higher consumption of unprocessed/minimally processed foods compared with those with lower consumption (HR, 0.71; 95% CI, 0.53-0.94; I2 = 11%). There was no association between risk of UC and ultra-processed foods (HR, 1.17; 95% CI, 0.86-1.61; I2 = 74%) or unprocessed/minimally processed foods (HR, 0.84; 95% CI, 0.68-1.02; I2 = 0%). CONCLUSIONS: Higher ultra-processed food and lower unprocessed/minimally processed food intakes are associated with higher risk of CD but not UC.


Asunto(s)
Colitis Ulcerosa , Enfermedad de Crohn , Enfermedades Inflamatorias del Intestino , Femenino , Humanos , Adulto , Persona de Mediana Edad , Masculino , Enfermedades Inflamatorias del Intestino/epidemiología , Riesgo , Manipulación de Alimentos
4.
Clin Gastroenterol Hepatol ; 21(6): 1607-1616.e6, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36243353

RESUMEN

BACKGROUND & AIMS: Industrial foods have been associated with increased risks of several chronic conditions. We investigated the relationship between the degree of food processing and risks of Crohn's disease (CD) and ulcerative colitis (UC) in the European Prospective Investigation into Cancer and Nutrition cohort. METHODS: Analyses included 413,590 participants (68.6% women; mean baseline age, 51.7 y) from 8 European countries. Dietary data were collected at baseline from validated country-specific dietary questionnaires. Associations between proportions of unprocessed/minimally processed and ultraprocessed food intake and CD and UC risks were estimated using Cox models to obtain hazard ratios (HRs) and 95% CIs. Models were stratified by center, age, and sex, and adjusted for smoking status, body mass index, physical activity, energy intake, educational level, and alcohol consumption. RESULTS: During a mean follow-up period of 13.2 years, 179 incident cases of CD and 431 incident cases of UC were identified. The risk of CD was lower in people consuming high proportions of unprocessed/minimally processed foods (adjusted HR for the highest vs lowest quartile: 0.57; 95% CI, 0.35-0.93; P trend < .01), particularly fruits and vegetables (adjusted HRs, 0.54; 95% CI, 0.34-0.87 and 0.55; 95% CI, 0.34-0.91, respectively). There was no association between unprocessed/minimally processed food intake and the risk of UC. No association was detected between ultraprocessed food consumption and CD or UC risks. CONCLUSIONS: In the European Prospective Investigation into Cancer and Nutrition cohort, consumption of unprocessed/minimally processed foods was associated with a lower risk of CD. No association between UC risk and food processing was found.


Asunto(s)
Colitis Ulcerosa , Enfermedad de Crohn , Humanos , Femenino , Persona de Mediana Edad , Masculino , Enfermedad de Crohn/epidemiología , Enfermedad de Crohn/etiología , Colitis Ulcerosa/epidemiología , Estudios Prospectivos , Factores de Riesgo , Encuestas y Cuestionarios , Manipulación de Alimentos
5.
Gut ; 2022 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-36591609

RESUMEN

OBJECTIVE: To estimate the proportion of cases of Crohn's disease (CD) and ulcerative colitis (UC) that could be prevented by modifiable lifestyle factors. DESIGN: In a prospective cohort study of US adults from the Nurses' Health Study (NHS; n=72 290), NHSII (n=93 909) and Health Professionals Follow-up Study (HPFS; n=41 871), we created modifiable risk scores (MRS; 0-6) for CD and UC based on established lifestyle risk factors, and healthy lifestyle scores (HLS; 0-9) derived from American healthy lifestyle recommendations. We calculated the population attributable risk by comparing the incidence of CD and UC between low-risk (CD-MRS≤1, UC-MRS≤2, HLS≥7) and high-risk groups. We externally validated our findings in three European cohorts: the Swedish Mammography Cohort (n=37 275), Cohort of Swedish Men (n=40 810) and European Prospective Investigation into Cancer and Nutrition (n=404 144). RESULTS: Over 5 117 021 person-years of follow-up (NHS, HPFS: 1986-2016; NHSII: 1991-2017), we documented 346 CD and 456 UC cases. Adherence to a low MRS could have prevented 42.9% (95% CI 12.2% to 66.1%) of CD and 44.4% (95% CI 9.0% to 69.8%) of UC cases. Similarly, adherence to a healthy lifestyle could have prevented 61.1% (95% CI 16.8% to 84.9%) of CD and 42.2% (95% CI 1.7% to 70.9%) of UC cases. In our validation cohorts, adherence to a low MRS and healthy lifestyle could have, respectively, prevented 43.9%-51.2% and 48.8%-60.4% of CD cases and 20.6%-27.8% and 46.8%-56.3% of UC cases. CONCLUSIONS: Across six US and European cohorts, a substantial burden of inflammatory bowel diseases risk may be preventable through lifestyle modification.

6.
Clin Gastroenterol Hepatol ; 20(5): 1048-1058, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34242756

RESUMEN

BACKGROUND AND AIMS: It is unclear whether obesity is associated with the development of inflammatory bowel disease despite compelling data from basic science studies. We therefore examined the association between obesity and risk of Crohn's disease (CD) and ulcerative colitis (UC). METHODS: We conducted pooled analyses of 5 prospective cohorts with validated anthropometric measurements for body mass index (BMI) and waist-hip ratio and other lifestyle factors. Diagnoses of CD and UC were confirmed through medical records or ascertained using validated definitions. We used Cox proportional hazards modeling to calculate pooled multivariable-adjusted HRs (aHRs) and 95% confidence intervals (CIs). RESULTS: Among 601,009 participants (age range, 18-98 years) with 10,110,018 person-years of follow-up, we confirmed 563 incident cases of CD and 1047 incident cases of UC. Obesity (baseline BMI ≥30 kg/m2) was associated with an increased risk of CD (pooled aHR, 1.34; 95% CI, 1.05-1.71, I2 = 0%) compared with normal BMI (18.5 to <25 kg/m2). Each 5 kg/m2 increment in baseline BMI was associated with a 16% increase in risk of CD (pooled aHR, 1.16; 95% CI, 1.05-1.22; I2 = 0%). Similarly, with each 5 kg/m2 increment in early adulthood BMI (age, 18-20 years), there was a 22% increase in risk of CD (pooled aHR, 1.22; 95% CI, 1.05-1.40; I2 = 13.6%). An increase in waist-hip ratio was associated with an increased risk of CD that did not reach statistical significance (pooled aHR across quartiles, 1.08; 95% CI, 0.97-1.19; I2 = 0%). No associations were observed between measures of obesity and risk of UC. CONCLUSIONS: In an adult population, obesity as measured by BMI was associated with an increased risk of older-onset CD but not UC.


Asunto(s)
Colitis Ulcerosa , Enfermedad de Crohn , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Colitis Ulcerosa/complicaciones , Colitis Ulcerosa/diagnóstico , Colitis Ulcerosa/epidemiología , Enfermedad de Crohn/complicaciones , Enfermedad de Crohn/diagnóstico , Enfermedad de Crohn/epidemiología , Humanos , Persona de Mediana Edad , Obesidad/complicaciones , Obesidad/epidemiología , Estudios Prospectivos , Factores de Riesgo , Adulto Joven
7.
Am J Med Genet A ; 188(5): 1589-1594, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35122461

RESUMEN

Microphthalmia, anophthalmia, and coloboma (MAC) are a heterogeneous spectrum of anomalous eye development and degeneration with genetic and environmental etiologies. Structural and copy number variants of chromosome 13 have been implicated in MAC; however, the specific loci involved in disease pathogenesis have not been well-defined. Herein we report a newborn with syndromic degenerative anophthalmia and a complex de novo rearrangement of chromosome 13q. Long-read genome sequencing improved the resolution and clinical interpretation of a duplication-triplication/inversion-duplication (DUP-TRP/INV-DUP) and terminal deletion. Sequence features at the breakpoint junctions suggested microhomology-mediated break-induced replication (MMBIR) of the maternal chromosome as the origin. Comparing this rearrangement to previously reported copy number alterations in 13q, we refine a putative dosage-sensitive critical region for MAC that might provide new insights into its molecular etiology.


Asunto(s)
Anoftalmos , Coloboma , Microftalmía , Anoftalmos/diagnóstico , Anoftalmos/genética , Anoftalmos/patología , Secuencia de Bases , Inversión Cromosómica , Mapeo Cromosómico , Coloboma/genética , Variaciones en el Número de Copia de ADN/genética , Humanos , Recién Nacido , Microftalmía/diagnóstico , Microftalmía/genética , Microftalmía/patología
8.
Curr Opin Gastroenterol ; 37(2): 121-127, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33315792

RESUMEN

PURPOSE OF REVIEW: Iron deficiency with anemia (IDA) and without anemia remain a diagnostic and management challenge. Iron deficiency has a broad spectrum of causes, including gastrointestinal malignancy. The purpose of this review is to summarize the value and limitations of current methods to diagnose iron deficiency and underline the relevance of contemporaneous evidence to guide the pretest probability of gastrointestinal disease. RECENT FINDINGS: A number of biomarkers for iron deficiency exist, and all have their caveats. Serum ferritin remains the most pragmatic means of diagnosing iron deficiency. Hepcidin holds future promise as a marker of iron status during inflammatory states. Men and postmenopausal women with IDA have the highest overall prevalence of gastrointestinal malignancy (∼11%), while premenopausal women with IDA (<1.5%) and those with iron deficiency without anemia (<0.5%) have a very low risk. Noninvasive investigation with fecal immunochemical test and fecal calprotectin hold promise to guide further investigations in lower risk groups. SUMMARY: Confirmation of iron deficiency remains a challenge. Appropriate risk stratification is the key to guiding judicious gastrointestinal investigation. Use of noninvasive tests may play an important role in lower risk groups. Risk prediction tools applicable to relevant populations are required.


Asunto(s)
Anemia Ferropénica , Enfermedades Gastrointestinales , Anemia Ferropénica/diagnóstico , Anemia Ferropénica/epidemiología , Biomarcadores , Femenino , Humanos , Hierro , Masculino , Prevalencia
9.
Gut ; 69(9): 1637-1644, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-31900290

RESUMEN

OBJECTIVE: To examine the relationship between Mediterranean diet and risk of later-onset Crohn's disease (CD) or ulcerative colitis (UC). DESIGN: We conducted a prospective cohort study of 83 147 participants (age range: 45-79 years) enrolled in the Cohort of Swedish Men and Swedish Mammography Cohort. A validated food frequency questionnaire was used to calculate an adherence score to a modified Mediterranean diet (mMED) at baseline in 1997. Incident diagnoses of CD and UC were ascertained from the Swedish Patient Register. We used Cox proportional hazards modelling to calculate HRs and 95% CI. RESULTS: Through December of 2017, we confirmed 164 incident cases of CD and 395 incident cases of UC with an average follow-up of 17 years. Higher mMED score was associated with a lower risk of CD (Ptrend=0.03) but not UC (Ptrend=0.61). Compared with participants in the lowest category of mMED score (0-2), there was a statistically significant lower risk of CD (HR=0.42, 95% CI 0.22 to 0.80) but not UC (HR=1.08, 95% CI 0.74 to 1.58). These associations were not modified by age, sex, education level, body mass index or smoking (all Pinteraction >0.30). The prevalence of poor adherence to a Mediterranean diet (mMED score=0-2) was 27% in our cohorts, conferring a population attributable risk of 12% for later-onset CD. CONCLUSION: In two prospective studies, greater adherence to a Mediterranean diet was associated with a significantly lower risk of later-onset CD.


Asunto(s)
Colitis Ulcerosa , Enfermedad de Crohn , Dieta Mediterránea , Cooperación del Paciente , Edad de Inicio , Anciano , Colitis Ulcerosa/diagnóstico , Colitis Ulcerosa/dietoterapia , Colitis Ulcerosa/epidemiología , Colitis Ulcerosa/prevención & control , Correlación de Datos , Enfermedad de Crohn/diagnóstico , Enfermedad de Crohn/dietoterapia , Enfermedad de Crohn/epidemiología , Enfermedad de Crohn/prevención & control , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Cooperación del Paciente/psicología , Cooperación del Paciente/estadística & datos numéricos , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Medición de Riesgo/métodos , Medición de Riesgo/estadística & datos numéricos , Conducta de Reducción del Riesgo , Encuestas y Cuestionarios , Suecia/epidemiología
10.
Clin Gastroenterol Hepatol ; 17(1): 123-129, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-29751165

RESUMEN

BACKGROUND & AIMS: Consumption of sweetened beverages has been associated with inflammation based on measurements of C-reactive protein and tumor necrosis factor, as well as immune-mediated disorders including rheumatoid arthritis. We investigated associations with Crohn's disease (CD) or ulcerative colitis (UC). METHODS: We conducted a prospective cohort study of 83,042 participants (age, 44-83 y) enrolled in the Cohort of Swedish Men or the Swedish Mammography Study. Dietary and lifestyle data were collected using a validated food frequency questionnaire at baseline in 1997. Diagnoses of CD and UC were ascertained from the Swedish Patient Register. We used Cox proportional hazards modeling to calculate hazard ratios and 95% CIs. RESULTS: Through December of 2014, we confirmed 143 incident cases of CD (incidence rate, 11 cases/100,000 person-years) and 349 incident cases of UC (incidence rate, 28 cases/100,000 person-years) over 1,264,345 person-years of follow-up evaluation. Consumption of sweetened beverages was not associated with increased risk of CD (Ptrend = .34) or UC (Ptrend = .40). Compared with participants who reported no consumption of sweetened beverages, the multivariable-adjusted hazard ratios for 1 or more servings per day were 1.02 for CD (95% CI, 0.60-1.73) and 1.14 for UC (95% CI, 0.83-1.57). The association between consumption of sugar-sweetened beverages and risk of CD or UC were not modified by age, sex (cohort), body mass index, or smoking (all Pinteraction ≥ .12). CONCLUSIONS: In analyses of data from 2 large prospective cohort studies from Sweden, we observed no evidence for associations between consumption of sweetened beverages and later risk of CD or UC.


Asunto(s)
Colitis Ulcerosa/epidemiología , Colitis Ulcerosa/etiología , Enfermedad de Crohn/epidemiología , Enfermedad de Crohn/etiología , Conducta Alimentaria , Bebidas Azucaradas/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Medición de Riesgo , Encuestas y Cuestionarios , Suecia/epidemiología
11.
Clin Gastroenterol Hepatol ; 21(4): 1122, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-35863684
12.
Gastrointest Endosc ; 87(2): 476-485, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28750840

RESUMEN

BACKGROUND AND AIMS: The role of electroacupuncture (EA) in reducing sedative and analgesic requirements during EUS is uncertain. The aim of this study was to investigate the efficacy of EA in reducing procedure-related pain and discomfort during EUS. METHODS: This was a double-blinded randomized controlled study conducted between March 2014 and July 2016. Consecutive patients who were scheduled for diagnostic EUS were recruited and randomized to receive EA or sham-electroacupuncture (SA). The primary outcome was the dosage of propofol used. Other outcome measurements included pain scores, anxiety scores, satisfaction scores, patients' willingness to repeat the procedure, total procedure time, and adverse events. RESULTS: A total of 128 patients were recruited to the study. The patients who received EA had significantly fewer requirements for patient-controlled sedation and analgesia (PCA). The median (interquartile range) number of demands for PCA (2 [1-5] vs 16.5 [8.5-33.8]; P < .001), the number of successful demands (2 [1-4] vs 9 [5.3-13]; P < .001), and the total dose of propofol (0.15 [0.08-0.34] vs 0.77 [0.38-1.09]; P < .001) and alfentanil (0.38 [0.20-0.86] vs 1.92 [0.94-2.72]; P < .001) were all significantly less. Patients who received EA also had significantly lower procedural pain scores and anxiety scores (P < .001), and higher satisfaction scores (P < .001), and they were more willing to repeat the procedure (P < .001). Being in the SA group and the procedure time were significant predictors of increased PCA demands (P < .001 and P = .009, respectively). CONCLUSIONS: In conclusion, the use of EA reduced sedative and analgesia demands, improved patient experience, and was associated with a low risk of adverse events during diagnostic EUS. (Clinical trial registration number: NCT02066194.).


Asunto(s)
Analgésicos Opioides/administración & dosificación , Electroacupuntura , Endosonografía/efectos adversos , Hipnóticos y Sedantes/administración & dosificación , Dolor/prevención & control , Anciano , Alfentanilo/administración & dosificación , Analgesia Controlada por el Paciente , Ansiedad/etiología , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dolor/etiología , Dimensión del Dolor , Aceptación de la Atención de Salud , Satisfacción del Paciente , Propofol/administración & dosificación , Estudios Prospectivos , Factores de Tiempo
13.
Nature ; 486(7403): 395-9, 2012 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-22495314

RESUMEN

Primary triple-negative breast cancers (TNBCs), a tumour type defined by lack of oestrogen receptor, progesterone receptor and ERBB2 gene amplification, represent approximately 16% of all breast cancers. Here we show in 104 TNBC cases that at the time of diagnosis these cancers exhibit a wide and continuous spectrum of genomic evolution, with some having only a handful of coding somatic aberrations in a few pathways, whereas others contain hundreds of coding somatic mutations. High-throughput RNA sequencing (RNA-seq) revealed that only approximately 36% of mutations are expressed. Using deep re-sequencing measurements of allelic abundance for 2,414 somatic mutations, we determine for the first time-to our knowledge-in an epithelial tumour subtype, the relative abundance of clonal frequencies among cases representative of the population. We show that TNBCs vary widely in their clonal frequencies at the time of diagnosis, with the basal subtype of TNBC showing more variation than non-basal TNBC. Although p53 (also known as TP53), PIK3CA and PTEN somatic mutations seem to be clonally dominant compared to other genes, in some tumours their clonal frequencies are incompatible with founder status. Mutations in cytoskeletal, cell shape and motility proteins occurred at lower clonal frequencies, suggesting that they occurred later during tumour progression. Taken together, our results show that understanding the biology and therapeutic responses of patients with TNBC will require the determination of individual tumour clonal genotypes.


Asunto(s)
Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Evolución Molecular , Mutación/genética , Alelos , Neoplasias de la Mama/diagnóstico , Células Clonales/metabolismo , Células Clonales/patología , Variaciones en el Número de Copia de ADN/genética , Análisis Mutacional de ADN , Progresión de la Enfermedad , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica/genética , Genotipo , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Mutación INDEL/genética , Mutación Puntual/genética , Medicina de Precisión , Reproducibilidad de los Resultados , Análisis de Secuencia de ARN
14.
PLoS Genet ; 11(9): e1005494, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26352591

RESUMEN

The centromeric histone 3 variant (CENH3, aka CENP-A) is essential for the segregation of sister chromatids during mitosis and meiosis. To better define CENH3 functional constraints, we complemented a null allele in Arabidopsis with a variety of mutant alleles, each inducing a single amino acid change in conserved residues of the histone fold domain. Many of these transgenic missense lines displayed wild-type growth and fertility on self-pollination, but exhibited frequent post-zygotic death and uniparental inheritance when crossed with wild-type plants. The failure of centromeres marked by these missense mutation in the histone fold domain of CENH3 reproduces the genome elimination syndromes described with chimeric CENH3 and CENH3 from diverged species. Additionally, evidence that a single point mutation is sufficient to generate a haploid inducer provide a simple one-step method for the identification of non-transgenic haploid inducers in existing mutagenized collections of crop species. As proof of the extreme simplicity of this approach to create haploid-inducing lines, we performed an in silico search for previously identified point mutations in CENH3 and identified an Arabidopsis line carrying the A86V substitution within the histone fold domain. This A87V non-transgenic line, while fully fertile on self-pollination, produced postzygotic death and uniparental haploids when crossed to wild type.


Asunto(s)
Arabidopsis/genética , Centrómero , Histonas/genética , Mutación Puntual , Sustitución de Aminoácidos , Codón , Genes de Plantas , Haploidia , Óvulo Vegetal , Polen
15.
PLoS Genet ; 11(1): e1004970, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25622028

RESUMEN

The point of attachment of spindle microtubules to metaphase chromosomes is known as the centromere. Plant and animal centromeres are epigenetically specified by a centromere-specific variant of Histone H3, CENH3 (a.k.a. CENP-A). Unlike canonical histones that are invariant, CENH3 proteins are accumulating substitutions at an accelerated rate. This diversification of CENH3 is a conundrum since its role as the key determinant of centromere identity remains a constant across species. Here, we ask whether naturally occurring divergence in CENH3 has functional consequences. We performed functional complementation assays on cenh3-1, a null mutation in Arabidopsis thaliana, using untagged CENH3s from increasingly distant relatives. Contrary to previous results using GFP-tagged CENH3, we find that the essential functions of CENH3 are conserved across a broad evolutionary landscape. CENH3 from a species as distant as the monocot Zea mays can functionally replace A. thaliana CENH3. Plants expressing variant CENH3s that are fertile when selfed show dramatic segregation errors when crossed to a wild-type individual. The progeny of this cross include hybrid diploids, aneuploids with novel genetic rearrangements and haploids that inherit only the genome of the wild-type parent. Importantly, it is always chromosomes from the plant expressing the divergent CENH3 that missegregate. Using chimeras, we show that it is divergence in the fast-evolving N-terminal tail of CENH3 that is causing segregation errors and genome elimination. Furthermore, we analyzed N-terminal tail sequences from plant CENH3s and discovered a modular pattern of sequence conservation. From this we hypothesize that while the essential functions of CENH3 are largely conserved, the N-terminal tail is evolving to adapt to lineage-specific centromeric constraints. Our results demonstrate that this lineage-specific evolution of CENH3 causes inviability and sterility of progeny in crosses, at the same time producing karyotypic variation. Thus, CENH3 evolution can contribute to postzygotic reproductive barriers.


Asunto(s)
Arabidopsis/genética , Autoantígenos/genética , Proteínas Cromosómicas no Histona/genética , Segregación Cromosómica/genética , Mitosis/genética , Secuencia de Aminoácidos , Animales , Arabidopsis/crecimiento & desarrollo , Evolución Biológica , Centrómero/genética , Proteína A Centromérica , Quimera/genética , Diploidia , Haploidia , Histonas/genética , Datos de Secuencia Molecular , Cigoto/crecimiento & desarrollo
16.
Gastroenterology ; 150(4): 854-65.e1; quiz e16-7, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26775632

RESUMEN

BACKGROUND & AIMS: Statins (3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors), commonly prescribed in the primary and secondary prevention of cardiovascular disease, promote apoptosis and limit proliferation of esophageal cancer cell lines. We investigated whether statin use after a diagnosis of esophageal cancer is associated with reduced esophageal cancer-specific and all-cause mortality. METHODS: We identified a cohort of 4445 men and women in the United Kingdom diagnosed with esophageal cancer from January 2000 through November 2009 using the General Practice Research Database. The National Cancer Registry and Office of National Statistics datasets established the histologic subtype and cancer-specific mortality, respectively. Cox proportional hazard regression analysis with time-dependent exposures estimated the association between statin use after diagnosis and esophageal cancer-specific and all-cause mortality. RESULTS: The median survival time of the entire cohort was 9.2 months (interquartile range [IQR], 3.7-23.2 mo). Among subjects who used statins after a diagnosis of esophageal cancer, the median survival time was 14.9 months (IQR, 7.1-52.3 mo) compared with 8.1 months for nonusers (IQR, 3.3-20 mo). In the entire cohort, statin use after diagnosis was associated with a decreased risk of esophageal cancer-specific mortality (adjusted hazard ratio [HR], 0.62; 95% confidence interval [CI], 0.44-0.86) and all-cause mortality (HR, 0.67; 95% CI, 0.58-0.77). In patients with esophageal adenocarcinoma, statin use after diagnosis was associated with a decreased risk of esophageal cancer-specific mortality (HR, 0.61; 95% CI 0.38-0.96) and all-cause mortality (HR, 0.63; 95% 0.43-0.92). This effect was not observed in patients with esophageal squamous cell carcinoma. There was no evidence for effect modification of these associations with statin use before the cancer diagnosis. CONCLUSIONS: In a large population-based cohort, statin use after a diagnosis of esophageal adenocarcinoma, but not esophageal squamous cell carcinoma, was associated with reduced esophageal cancer-specific and all-cause mortality.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Neoplasias Esofágicas/tratamiento farmacológico , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Adenocarcinoma/diagnóstico , Adenocarcinoma/mortalidad , Anciano , Anciano de 80 o más Años , Distribución de Chi-Cuadrado , Relación Dosis-Respuesta a Droga , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/mortalidad , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Análisis Multivariante , Modelos de Riesgos Proporcionales , Factores Protectores , Sistema de Registros , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Reino Unido/epidemiología
17.
BMC Musculoskelet Disord ; 18(1): 337, 2017 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-28778219

RESUMEN

BACKGROUND: We examined the effectiveness and tolerability of transdermal buprenorphine (TDB) treatment in real-world setting in Asian patients with musculoskeletal pain. METHODS: This was an open-label study conducted in Hong Kong, Korea, and the Philippines between June 2013 and April 2015. Eligible patients fulfilled the following criteria: 18 to 80 years of age; clinical diagnosis of osteoarthritis, rheumatoid arthritis, low back pain, or joint/muscle pain; chronic non-malignant pain of moderate to severe intensity (Box-Scale-11 [BS-11] pain score ≥ 4), not adequately controlled with non-opioid analgesics and requiring an opioid for adequate analgesia; and no prior history of opioid treatment. Patients started with a 5 µg/h buprenorphine patch and were titrated as necessary to a maximum of 40 µg/h over a 6-week period to achieve optimal pain control. Patients continued treatment with the titrated dose for 11 weeks. The primary efficacy endpoint was the change in BS-11 pain scores. Other endpoints included patients' sleep quality and quality of life as assessed by the 8-item Global Sleep Quality Assessment Scale (GSQA) questionnaire and the EuroQol Group 5-Dimension Self-Report Questionnaire-3 Level version (EQ-5D-3 L), respectively. Tolerability was assessed by collecting adverse events. RESULTS: A total of 114 eligible patients were included in the analysis. The mean BS-11 score at baseline was 6.2 (SD 1.6). Following initiation of TDB, there was a statistically significant improvement in BS-11 score from baseline to visit 3 (least squares [LS] mean change: -2.27 [95% CI -2.66 to -1.87]), which was maintained till the end of the study (visit 7) (LS mean change: -2.64 [95% -3.05 to -2.23]) (p < 0.0001 for both). The proportion of patients who rated sleep quality as 'good' increased from 14.0% at baseline to 26.9% at visit 6. By visit 6, the mean EQ VAS score increased by 7.7 units (SD 17.9). There were also significant improvements in patients' levels of functioning for all EQ-5D-3 L dimensions from baseline at visit 6 (p < 0.05 for all). Seventy-eight percent of patients reported TEAEs and 22.8% of patients discontinued due to TEAEs. TEAEs were generally mild to moderate in intensity (96.5%). CONCLUSIONS: TDB provides effective pain relief with an acceptable tolerability profile over the 11-week treatment period in Asian patients with chronic musculoskeletal pain. More studies are needed to examine the long-term efficacy and safety of TBD treatment in this patient population. TRIAL REGISTRATION: ClinicalTrials.gov NCT01961271 . Registered 7 October 2013 (retrospectively registered; first patient was enrolled on 28 June 2013 and last patient last visit date was 26 Apr 2015).


Asunto(s)
Analgésicos Opioides/uso terapéutico , Buprenorfina/uso terapéutico , Dolor Crónico/tratamiento farmacológico , Dolor Musculoesquelético/tratamiento farmacológico , Parche Transdérmico/efectos adversos , Administración Cutánea , Adulto , Anciano , Femenino , Hong Kong , Humanos , Masculino , Persona de Mediana Edad , Manejo del Dolor/métodos , Dimensión del Dolor , Filipinas , Estudios Prospectivos , Calidad de Vida , República de Corea , Encuestas y Cuestionarios , Resultado del Tratamiento
18.
Nature ; 464(7288): 615-8, 2010 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-20336146

RESUMEN

Production of haploid plants that inherit chromosomes from only one parent can greatly accelerate plant breeding. Haploids generated from a heterozygous individual and converted to diploid create instant homozygous lines, bypassing generations of inbreeding. Two methods are generally used to produce haploids. First, cultured gametophyte cells may be regenerated into haploid plants, but many species and genotypes are recalcitrant to this process. Second, haploids can be induced from rare interspecific crosses, in which one parental genome is eliminated after fertilization. The molecular basis for genome elimination is not understood, but one theory posits that centromeres from the two parent species interact unequally with the mitotic spindle, causing selective chromosome loss. Here we show that haploid Arabidopsis thaliana plants can be easily generated through seeds by manipulating a single centromere protein, the centromere-specific histone CENH3 (called CENP-A in human). When cenh3 null mutants expressing altered CENH3 proteins are crossed to wild type, chromosomes from the mutant are eliminated, producing haploid progeny. Haploids are spontaneously converted into fertile diploids through meiotic non-reduction, allowing their genotype to be perpetuated. Maternal and paternal haploids can be generated through reciprocal crosses. We have also exploited centromere-mediated genome elimination to convert a natural tetraploid Arabidopsis into a diploid, reducing its ploidy to simplify breeding. As CENH3 is universal in eukaryotes, our method may be extended to produce haploids in any plant species.


Asunto(s)
Arabidopsis/genética , Arabidopsis/metabolismo , Centrómero/metabolismo , Genoma de Planta/genética , Haploidia , Histonas/genética , Histonas/metabolismo , Núcleo Celular/genética , Cruzamientos Genéticos , Diploidia
19.
Dig Dis Sci ; 61(10): 2963-2971, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27461060

RESUMEN

BACKGROUND: Industrialization has been linked to the etiology of inflammatory bowel disease (IBD). AIM: We investigated the association between air pollution exposure and IBD. METHODS: The European Prospective Investigation into Cancer and Nutrition cohort was used to identify cases with Crohn's disease (CD) (n = 38) and ulcerative colitis (UC) (n = 104) and controls (n = 568) from Denmark, France, the Netherlands, and the UK, matched for center, gender, age, and date of recruitment. Air pollution data were obtained from the European Study of Cohorts for Air Pollution Effects. Residential exposure was assessed with land-use regression models for particulate matter with diameters of <10 µm (PM10), <2.5 µm (PM2.5), and between 2.5 and 10 µm (PMcoarse), soot (PM2.5 absorbance), nitrogen oxides, and two traffic indicators. Conditional logistic regression analyses were performed to calculate odds ratios (ORs) with 95 % confidence intervals (CIs). RESULTS: Although air pollution was not significantly associated with CD or UC separately, the associations were mostly similar. Individuals with IBD were less likely to have higher exposure levels of PM2.5 and PM10, with ORs of 0.24 (95 % CI 0.07-0.81) per 5 µg/m(3) and 0.25 (95 % CI 0.08-0.78) per 10 µg/m(3), respectively. There was an inverse but nonsignificant association for PMcoarse. A higher nearby traffic load was positively associated with IBD [OR 1.60 (95 % CI 1.04-2.46) per 4,000,000 motor vehicles × m per day]. Other air pollutants were positively but not significantly associated with IBD. CONCLUSION: Exposure to air pollution was not found to be consistently associated with IBD.


Asunto(s)
Contaminación del Aire/estadística & datos numéricos , Colitis Ulcerosa/epidemiología , Enfermedad de Crohn/epidemiología , Exposición a Riesgos Ambientales/estadística & datos numéricos , Material Particulado , Adulto , Estudios de Casos y Controles , Dinamarca/epidemiología , Europa (Continente)/epidemiología , Femenino , Francia/epidemiología , Humanos , Incidencia , Enfermedades Inflamatorias del Intestino/epidemiología , Modelos Logísticos , Masculino , Persona de Mediana Edad , Países Bajos/epidemiología , Oportunidad Relativa , Reino Unido/epidemiología , Emisiones de Vehículos
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