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1.
Acta Odontol Scand ; 81(2): 158-163, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35943761

RESUMO

CONCLUSION: Primary canines and first molars can be extracted in a way that is associated with relatively low levels of pain and discomfort during and after the procedures. Double extractions induced more pain and discomfort than single extractions, which should be accounted for in the treatment planning. MATERIAL AND METHODS: Twenty-eight children, aged 9.5-14 years with displaced permanent maxillary canines were randomly assigned for extraction of the primary canine only or the primary canine and the primary first molar. Pain and discomfort were rated on visual analogue scales, and influence on daily activities was assessed by a questionnaire that has been previously tested for reliability and validity. Differences between groups were assessed by independent samples t-tests, Mann-Whitney U-tests or the Fisher's exact test. OBJECTIVE: To assess pain, discomfort, and functional impairment in children experiencing extraction of primary canine or primary canine and primary first molar as an interceptive treatment for palatally displaced permanent canines. RESULTS: Tooth extraction was associated with low levels of pain and discomfort on a group level. Extraction of both the canine and the first molar was associated with significantly more pain and discomfort than was the extraction of the canine only. Extractions were associated with chewing problems among one-third to half of the children, otherwise, few children reported any jaw impairment after extraction.


Assuntos
Erupção Ectópica de Dente , Extração Dentária , Humanos , Dente Canino/cirurgia , Maxila , Dente Molar/cirurgia , Dor , Reprodutibilidade dos Testes , Erupção Ectópica de Dente/terapia , Extração Dentária/efeitos adversos , Dente Decíduo , Dor Pós-Operatória
3.
Angle Orthod ; 90(6): 751-757, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-33378508

RESUMO

OBJECTIVES: To compare the impact of primary canine and primary first molar extractions with extractions of only the primary canine regarding correction of palatally displaced canines (PDCs). MATERIALS AND METHODS: Thirty-two children aged 9.5-13.5 years with 48 PDCs were randomly allocated to either the double-extraction group (DEG) or single-extraction group (SEG). Clinical and radiographic examinations were performed at baseline and at 6-month intervals until the canine emerged or orthodontic treatment was started. Outcome measures were: emergence of maxillary canine (yes/no), emergence of maxillary canine into a favorable position (yes/no), and maxillary canine positional change (angulation and sector). Factors influencing PDC emergence were analyzed using logistic regression. RESULTS: In the DEG, 64% (16/25) of canines emerged into the oral cavity vs 78% (18/23) in the SEG (P = .283). Favorable PDC position at trial end was seen in 64% (16/25) of the DEG vs 57% (13/23) of the SEG (P = .600). Significant distal movement of PDCs was recorded in the DEG and SEG, though no significant difference was observed between groups. Significant predictors of canine emergence were initial canine angulation (Angle A) (P = .008) and space conditions at T0 (P = .030). CONCLUSIONS: Double or single primary tooth extraction procedures are equivalent in supporting PDC eruption into the oral cavity and into a favorable position in the dental arch. Initial canine angulation and space assessments may be used as predictors of successful PDC eruption.


Assuntos
Erupção Ectópica de Dente , Dente Impactado , Adolescente , Criança , Dente Canino/diagnóstico por imagem , Dente Canino/cirurgia , Humanos , Maxila/diagnóstico por imagem , Maxila/cirurgia , Ortodontia Interceptora , Erupção Ectópica de Dente/diagnóstico por imagem , Erupção Ectópica de Dente/terapia , Extração Dentária , Dente Decíduo , Dente Impactado/diagnóstico por imagem , Dente Impactado/cirurgia , Resultado do Tratamento
4.
Int J Otolaryngol ; 2020: 2856460, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32665778

RESUMO

In this randomized controlled trial, patients with nonsevere obstructive sleep apnea (OSA) were treated with continuous positive airway pressure (CPAP) or a twin block mandibular advancement splint (MAS). The primary objective was to compare how CPAP and MAS treatments change the health-related quality of life (HRQoL) and self-reported sleep quality of patients after 12 months of treatment. In total, 104 patients were recruited: 55 were allocated to the CPAP treatment group and 49 to the MAS treatment group. We used the SF36 questionnaire to evaluate HRQoL and the Pittsburgh Sleep Quality Index (PSQI) to evaluate sleep quality. All patients were included in the intention-to-treat analyses. These analyses showed improvements in the SF36 physical component score (from 48.8 ± 7.6 at baseline to 50.5 ± 8.0 at follow-up, p=0.03) in the CPAP treatment group and in the mental component score (from 44.9 ± 12.1 to 49.3 ± 9.2, p=0.009) in the MAS treatment group. The PSQI global score improved in both the CPAP (from 7.7 ± 3.5 to 6.6 ± 2.9, p=0.006) and the MAS (8.0 ± 3.1 to 6.1 ± 2.6, p < 0.001) treatment groups. No difference was found between the treatment groups in any of the SF36 scores or PSQI global score at the final follow-up (p > 0.05) in any analysis. The improvement in the SF36 vitality domain moderately correlated to the improvement in the PSQI global score in both groups (CPAP: |r|=0.47, p < 0.001; MAS: |r|=0.36, p=0.01). In the MAS treatment group, we also found a weak correlation between improvements in the SF36 mental component score and PSQI global score (|r|=0.28, p=0.05). In conclusion, CPAP and MAS treatments lead to similar improvements in the HRQoL and self-reported sleep quality in nonsevere OSA. Improvements in aspects of HRQoL seem to be moderately correlated to the self-reported sleep quality in both CPAP and MAS treatments.

5.
Int J Otolaryngol ; 2020: 6459276, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32256602

RESUMO

Nonsevere obstructive sleep apnea (OSA) is most often treated with a continuous positive airway pressure (CPAP) device or a mandibular advancement splint (MAS). However, patient compliance with these treatments is difficult to predict. Improvement in apnea-hypopnea index (AHI) is also somewhat unpredictable in MAS treatment. In this study, we investigated the association between Friedman tongue position score (Friedman score) and both treatment compliance and AHI improvement in patients with nonsevere OSA receiving CPAP or MAS treatment. 104 patients with nonsevere OSA were randomly allocated to CPAP or MAS treatment and followed for 12 months. Data were collected through a medical examination, questionnaires, sleep recordings from ambulatory type 3 polygraphic sleep recording devices, and CPAP recordings. Associations between Friedman score, treatment compliance, and AHI improvement were analysed with logistic regression analyses. Friedman score was not associated with treatment compliance (odds ratio [OR]: 0.85, 95% confidence interval [CI]: 0.59-1.23), or AHI improvement (OR: 1.05, 95% CI: 0.62-1.76) in the overall study sample, the CPAP treatment group, or the MAS treatment group. Adjustment for socioeconomic factors, body mass index, and tonsil size did not significantly impact the results. Although Friedman score may predict OSA severity and contribute to the prediction of success in uvulopalatopharyngoplasty, we found no association between Friedman score and treatment compliance in patients with nonsevere OSA receiving CPAP or MAS treatment, nor did we find any association between Friedman score and AHI improvement. Factors other than Friedman score should be considered when deciding whether a patient with nonsevere OSA should be treated with CPAP or MAS.

6.
Eur J Orthod ; 40(6): 583-591, 2018 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-29617758

RESUMO

Objective: To test whether early headgear (HG) treatment and space conditions in the dental arch affect the eruption pathway of the maxillary canines in young children with mixed dentition. Subjects and methods: Data from two randomized controlled trials studying the effects of early HG treatment were pooled, yielding a study sample comprising 99 children (38 girls and 61 boys, mean age 7.6 years) with Angle Class II occlusion. Fifty-one children were treated with HG and 48 children served as an untreated control group (CG). Digital 3D models and panoramic radiographs were taken before (T0) and after (T1) treatment, and changes in the maxillary canine eruption angle and interdental spaces were measured at T0 and T1. A paired samples t-test was used to assess changes in maxillary canine angulation, and an independent samples t-test was used to evaluate the effect of HG treatment on spacing in the dental arch. Associations between intra-arch space conditions and changes in maxillary canine angulation were estimated with linear regression models. Results: The eruption pattern of the permanent canine was significantly more vertical in the HG group than in the CG. The linear regression models showed a statistically significant association among the intercanine distance, crowding in the anterior part of the maxilla, and changes in the maxillary canine eruption angle. The maxillary canine eruption pattern changed significantly more to a vertical direction in spaced dental arches than in crowded dental arches in the HG group. Conclusion: This study shows that early HG treatment in children with Angle Class II occlusion may change the eruption pattern of permanent maxillary canines to a more vertical direction. This change appears to be related to space conditions in the maxillary arch, especially in the intercanine region, with more effect in children with spaced dental arches than in children with crowded dental arches.


Assuntos
Dente Canino/crescimento & desenvolvimento , Aparelhos de Tração Extrabucal , Má Oclusão Classe II de Angle/terapia , Erupção Dentária , Criança , Dente Canino/diagnóstico por imagem , Dente Canino/patologia , Arco Dental/diagnóstico por imagem , Arco Dental/patologia , Dentição Mista , Feminino , Humanos , Masculino , Má Oclusão Classe II de Angle/diagnóstico por imagem , Má Oclusão Classe II de Angle/patologia , Maxila/diagnóstico por imagem , Maxila/patologia , Radiografia Panorâmica , Ensaios Clínicos Controlados Aleatórios como Assunto
7.
Gigascience ; 4: 40, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26351566

RESUMO

BACKGROUND: In metagenomics, microbial communities are sequenced at increasingly high resolution, generating datasets with billions of DNA fragments. Novel methods that can efficiently process the growing volumes of sequence data are necessary for the accurate analysis and interpretation of existing and upcoming metagenomes. FINDINGS: Here we present Tentacle, which is a novel framework that uses distributed computational resources for gene quantification in metagenomes. Tentacle is implemented using a dynamic master-worker approach in which DNA fragments are streamed via a network and processed in parallel on worker nodes. Tentacle is modular, extensible, and comes with support for six commonly used sequence aligners. It is easy to adapt Tentacle to different applications in metagenomics and easy to integrate into existing workflows. CONCLUSIONS: Evaluations show that Tentacle scales very well with increasing computing resources. We illustrate the versatility of Tentacle on three different use cases. Tentacle is written for Linux in Python 2.7 and is published as open source under the GNU General Public License (v3). Documentation, tutorials, installation instructions, and the source code are freely available online at: http://bioinformatics.math.chalmers.se/tentacle.


Assuntos
Biologia Computacional , Metagenoma
8.
Eur J Orthod ; 34(5): 587-94, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21345928

RESUMO

This study investigated the early effects on mandibular incisor irregularity and rotation together with dental arch dimensions of the extraction of four deciduous canines. Children, during early mixed dentition, were randomized into one extraction (n = 32) and one control (n = 41) group. Dental casts from baseline (T0) and 1 year follow-up (T1) were used to evaluate changes in the irregularity index and in mandibular incisor rotation, dental arch dimensions, overjet, and overbite. Median mandibular incisor irregularity decreased over time, significantly more in the extraction than the control group (1.2 versus 0.7 mm; P < 0.01), with wide ranges in both groups. Rotational changes greater than 10 degrees for lateral incisors were twice as common in the extraction group (42 versus 20 per cent; P < 0.01). Central incisors displayed only minor changes in both groups. The correlation between changes in irregularity index and changes in incisor rotation was weak in both groups (r(s) < 0.3 not significant). According to professional assessment of overall alignment, 84 per cent in the extraction group versus 34 per cent in the control group (P < 0.001) improved from T0 to T1. A significant decrease in maxillary and mandibular arch length and circumference from T0 to T1 was recorded in the extraction group (1.3, 1.1 mm and 2.4, 2.0 mm, respectively; P < 0.001), while arch dimensions were preserved in the control group. To conclude, 1 year after extraction of the deciduous canines, small improvements in mandibular incisor alignment were seen, together with reduced arch dimensions. Little's index underestimated malalignment related to tooth rotation.


Assuntos
Dente Canino/cirurgia , Arco Dental/anatomia & histologia , Incisivo/anatomia & histologia , Ortodontia Corretiva/métodos , Extração Dentária , Dente Decíduo/cirurgia , Criança , Dentição Mista , Feminino , Humanos , Masculino
9.
Int J Paediatr Dent ; 20(3): 193-200, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20409200

RESUMO

BACKGROUND: Interceptive extractions of deciduous canines are, from a patient perspective, poorly investigated. AIMS: To describe pain, discomfort, and dental fear in connection to extractions of the deciduous canines, indicated as an orthodontic treatment procedure. DESIGN: Thirty-two Swedish children aged 7-9 years had all four deciduous canines extracted over three occasions. The children rated procedural and postoperative pain on visual analogue scales. Acceptance of injections and extractions was assessed by the treating dentists. Analgesic consumption and recovery time for drinking and eating was reported by parents. Dental fear was assessed using the Children's Fear Survey Schedule questionnaire. RESULTS: Procedural pain showed low median levels, although some individuals reported high values. Boys reported significantly more pain at appointments when two (as opposed to one) canines were extracted. Postoperative pain levels were low and use of analgesics sparse. Dental fear paralleled norm values and did not increase from pre- to post-extraction. CONCLUSIONS: Pain management routines during extractions of this kind should be revised. Single tooth extractions seem to be preferable to extractions of two canines at the same appointment. Extraction of four deciduous canines should not cause major postoperative inconvenience; these extractions neither triggered nor increased dental fear.


Assuntos
Analgésicos/uso terapêutico , Ansiedade ao Tratamento Odontológico/psicologia , Dor Pós-Operatória/psicologia , Dor/psicologia , Extração Dentária/psicologia , Analgesia/psicologia , Criança , Dente Canino , Assistência Odontológica para Crianças/psicologia , Feminino , Humanos , Masculino , Ortodontia Interceptora/métodos , Ortodontia Interceptora/psicologia , Dor/prevenção & controle , Dor Pós-Operatória/prevenção & controle , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Dente Decíduo/cirurgia
10.
J Digit Imaging ; 23(4): 482-92, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19526268

RESUMO

Digital imaging of dental casts has become an alternative to conventional cast analysis in orthodontic treatment planning. The reproducibility of angular measurements made on virtual digital models has not as yet been evaluated. In order to study reproducibility for and agreement between a conventional analysis technique and virtual 3D imaging, 20 dental casts from subjects in the early mixed dentition, were measured twice with each technique by two orthodontists. Variables of interest were incisor rotation, angulation and irregularity, arch width, arch circumference, overjet, and overbite. Standard deviation (Dahlberg 1940) and coefficient of variation were used for evaluation of reproducibility. Mean differences between methods and examiners, correlation between mean differences and mean levels and 95% limits of agreement were used for describing systematic errors. The conventional technique showed less intraexaminer variation for angular variables than the 3D imaging method. Linear variables, with the exception of overbite, showed no clear trend as regards differences in reproducibility between the two methods. In general, examiner 1 showed less intraexaminer variation than examiner 2. The mean differences between the two methods expressed higher values for assessment of rotations with the O3DM method. Both angular and linear variables exhibited poor 95% limits of agreement. The conventional technique showed better overall reproducibility and thus appears to be more suitable for scientific work. However, the reproducibility attained by O3DM is clearly acceptable for clinical use. The two methods should not be used interchangeably.


Assuntos
Técnica de Fundição Odontológica , Interpretação de Imagem Assistida por Computador , Imageamento Tridimensional/métodos , Interface Usuário-Computador , Arco Dental/patologia , Técnica de Moldagem Odontológica , Feminino , Humanos , Masculino , Má Oclusão/diagnóstico , Modelos Dentários , Variações Dependentes do Observador , Odontometria/métodos , Estudos Prospectivos , Reprodutibilidade dos Testes
11.
Metabolism ; 58(1): 102-8, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19059537

RESUMO

Insulin resistance develops rapidly during critical illness. The release of adipokines from adipose tissue is thought to play a key role in the development of insulin resistance, as are elevated levels of acute-phase proteins. The aim of this study was to identify changes in adipose tissue gene expression and plasma levels of adipokines and acute-phase proteins during critical illness. From 8 patients with subarachnoidal hemorrhage, consecutive blood samples and adipose tissue biopsies were obtained at 3 time points, twice during intensive care (1-2 days [IC1] and 7-9 days after subarachnoidal hemorrhage) and once after 8 months (recovery). The patients received a continuous insulin infusion to maintain normal glucose levels reflecting insulin resistance. The DNA microarray analysis showed increased zink-alpha2 glycoprotein (ZAG) and phospholipase A2, group IIA messenger RNA levels during intensive care compared with recovery (P < .05). Real-time polymerase chain reaction confirmed the increased expression of ZAG and phospholipase A2, group IIA. Plasma levels of ZAG, serum amyloid A, and C-reactive protein were higher at 7 to 9 days after subarachnoidal hemorrhage compared with either IC1 or recovery (P = .0001); and plasma levels of retinol-binding protein 4 and adiponectin were lower at IC1 compared with recovery (P = .05). The described changes in adipose tissue gene expression and plasma levels of adipokines and acute-phase proteins may influence the development of insulin resistance during critical illness.


Assuntos
Proteínas de Fase Aguda/metabolismo , Adipocinas/sangue , Tecido Adiposo/fisiologia , Regulação da Expressão Gênica , Resistência à Insulina/fisiologia , Hemorragia Subaracnóidea/genética , Proteínas de Fase Aguda/genética , Adipocinas/biossíntese , Adipocinas/genética , Tecido Adiposo/metabolismo , Biópsia , Glicemia/metabolismo , Estado Terminal , Feminino , Humanos , Insulina/uso terapêutico , Resistência à Insulina/genética , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , RNA/química , RNA/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Hemorragia Subaracnóidea/sangue
12.
Anticancer Res ; 28(5B): 2851-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19031924

RESUMO

AIM: To evaluate weekly induction chemotherapy followed by weekly concomitant chemoradiotherapy in a multicentre phase II study of patients with unresectable stage III non-small cell lung cancer (NSCLC; stage wet IIIB excluded). PATIENTS AND METHODS: Eligible patients received three weekly cycles of paclitaxel 100 mg/m2 and carboplatin AUC2 followed by six weekly cycles of paclitaxel 60 mg/m2 and carboplatin AUC2 in combination with thoracic radiotherapy (2 Gy per fraction and day to a total dose of 60 Gy). RESULTS: Sixty-four patients (40 males and 24 females) with a median age of 63 years (range, 43-79 years) entered the study. T and N stage were distributed as follows: T1 2 patients (3.2%), T2 10 patients (15.6%), T3 15 patients (23.4%), T4 37 patients (57.8%); N0 10 patients (15.6%), N1 1 patient (1.6%), N2 26 patients (40.6%), N3 26 patients (40.6%), and N missing 1 patient (1.6%). Seven patients (10.9%) suffered from grade 3/4 oesophagitis. Grade 1/2 oesophagitis occurred in 36 patients (56.3%) and pneumonitis grade 1/2 occurred in 10 patients (15.6%). Sixty-three patients were evaluated on an intent-to-treat basis. The overall response rate was 74.6%. The median time to progression was 247 days and median overall survival was 461 days. According to subgroup analyses, no statistically significant differences were noted according to gender, age (<65 vs. > or =65 years), performance status, histology, or study centre. CONCLUSION: Induction chemotherapy followed by concurrent chemoradiotherapy with weekly cycles of paclitaxel and carboplatin is feasible and generates moderate toxicity. Efficacy is comparable to other recently published regimens. However, prognosis remains, in general, poor for this group of patients and further work to develop better therapy is required.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/radioterapia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carboplatina/administração & dosagem , Carboplatina/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/patologia , Terapia Combinada , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Paclitaxel/administração & dosagem , Paclitaxel/efeitos adversos , Taxa de Sobrevida
13.
BMC Bioinformatics ; 8: 387, 2007 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-17937807

RESUMO

BACKGROUND: In DNA microarray experiments, measurements from different biological samples are often assumed to be independent and to have identical variance. For many datasets these assumptions have been shown to be invalid and typically lead to too optimistic p-values. A method called WAME has been proposed where a variance is estimated for each sample and a covariance is estimated for each pair of samples. The current version of WAME is, however, limited to experiments with paired design, e.g. two-channel microarrays. RESULTS: The WAME procedure is extended to general microarray experiments, making it capable of handling both one- and two-channel datasets. Two public one-channel datasets are analysed and WAME detects both unequal variances and correlations. WAME is compared to other common methods: fold-change ranking, ordinary linear model with t-tests, LIMMA and weighted LIMMA. The p-value distributions are shown to differ greatly between the examined methods. In a resampling-based simulation study, the p-values generated by WAME are found to be substantially more correct than the alternatives when a relatively small proportion of the genes is regulated. WAME is also shown to have higher power than the other methods. WAME is available as an R-package. CONCLUSION: The WAME procedure is generalized and the limitation to paired-design microarray datasets is removed. The examined other methods produce invalid p-values in many cases, while WAME is shown to produce essentially valid p-values when a relatively small proportion of genes is regulated. WAME is also shown to have higher power than the examined alternative methods.


Assuntos
Algoritmos , Interpretação Estatística de Dados , Perfilação da Expressão Gênica/métodos , Modelos Genéticos , Modelos Estatísticos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Simulação por Computador
14.
FASEB J ; 20(9): 1540-2, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16754744

RESUMO

Enlarged adipocytes are associated with insulin resistance and are an independent predictor of type 2 diabetes. To understand the molecular link between these diseases and adipocyte hypertrophy, we developed a technique to separate human adipocytes from an adipose tissue sample into populations of small cells (mean 57.6+/-3.54 microm) and large cells (mean 100.1+/-3.94 microm). Microarray analysis of the cell populations separated from adipose tissue from three subjects identified 14 genes, of which five immune-related, with more than fourfold higher expression in large cells than small cells. Two of these genes were serum amyloid A (SAA) and transmembrane 4 L six family member 1 (TM4SF1). Real-time RT-PCR analysis of SAA and TM4SF1 expression in adipocytes from seven subjects revealed 19-fold and 22-fold higher expression in the large cells, respectively, and a correlation between adipocyte size and both SAA and TM4SF1 expression. The results were verified using immunohistochemistry. In comparison with 17 other human tissues and cell types by microarray, large adipocytes displayed by far the highest SAA and TM4SF1 expression. Thus, we have identified genes with markedly higher expression in large, compared with small, human adipocytes. These genes may link hypertrophic obesity to insulin resistance/type 2 diabetes.


Assuntos
Adipócitos/citologia , Adipócitos/fisiologia , Regulação da Expressão Gênica , Adipócitos/patologia , Tamanho Celular , Feminino , Humanos , Hipertrofia , Resistência à Insulina/fisiologia , Leptina/genética , Leptina/fisiologia , Masculino , Pós-Menopausa , Reação em Cadeia da Polimerase Via Transcriptase Reversa
15.
Stat Appl Genet Mol Biol ; 5: Article10, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16646864

RESUMO

In microarray experiments, several steps may cause sub-optimal quality and the need for quality control is strong. Often the experiments are complex, with several conditions studied simultaneously. A linear model for paired microarray experiments is proposed as a generalisation of the paired two-sample method by Kristiansson et al. (2005). Quality variation is modelled by different variance scales for different (pairs of) arrays, and shared sources of variation are modelled by covariances between arrays. The gene-wise variance estimates are moderated in an empirical Bayes approach. Due to correlations all data is typically used in the inference of any linear combination of parameters. Both real and simulated data are analysed. Unequal variances and strong correlations are found in real data, leading to further examination of the fit of the model and of the nature of the datasets in general. The empirical distributions of the test-statistics are found to have a considerably improved match to the null distribution compared to previous methods, which implies more correct p-values provided that most genes are non-differentially expressed. In fact, assuming independent observations with identical variances typically leads to optimistic p-values. The method is shown to perform better than the alternatives in the simulation study.


Assuntos
Perfilação da Expressão Gênica/normas , Análise de Sequência com Séries de Oligonucleotídeos/normas , Animais , Apolipoproteína A-I/biossíntese , Apolipoproteína A-I/genética , Teorema de Bayes , Coração Auxiliar , Humanos , Modelos Lineares , Camundongos , Miocárdio/metabolismo , Controle de Qualidade , Curva ROC
16.
Obes Res ; 13(4): 649-52, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15897472

RESUMO

OBJECTIVE: The aim of this study was to evaluate reference genes for expression studies of human adipose tissue. RESEARCH METHODS AND PROCEDURES: Using 52 human adipose tissue expression profiles (HU95), 10 putative reference genes with the lowest variation in expression levels were selected for further studies. Expression stability of these 10 novel and 5 previously established reference genes was evaluated by real-time reverse transcriptase-polymerase chain reaction analysis. For this purpose, 44 adipose tissue biopsies from 27 subjects were chosen to include a wide range of parameters such as sex, age, BMI, depot origin, biopsy procedure, and effects of nutrition. RESULTS: LRP10 was identified as the gene with the least variation in expression levels. The frequently used reference genes RPLP0, 18S rRNA, PPIA, ACTB, and GAPD were ranked as 4, 6, 7, 8, and 10, respectively. DISCUSSION: Our results suggest that LRP10 is a better choice as reference for expression studies of human adipose tissue compared with the most frequently used reference genes.


Assuntos
Tecido Adiposo/metabolismo , Expressão Gênica , Adulto , Envelhecimento , Biópsia/métodos , Índice de Massa Corporal , Feminino , Perfilação da Expressão Gênica , Humanos , Proteínas Relacionadas a Receptor de LDL , Masculino , Proteínas de Membrana Transportadoras/genética , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Receptores de LDL/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Caracteres Sexuais
17.
Stat Appl Genet Mol Biol ; 4: Article30, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16646849

RESUMO

In microarray experiments quality often varies, for example between samples and between arrays. The need for quality control is therefore strong. A statistical model and a corresponding analysis method is suggested for experiments with pairing, including designs with individuals observed before and after treatment and many experiments with two-colour spotted arrays. The model is of mixed type with some parameters estimated by an empirical Bayes method. Differences in quality are modelled by individual variances and correlations between repetitions. The method is applied to three real and several simulated datasets. Two of the real datasets are of Affymetrix type with patients profiled before and after treatment, and the third dataset is of two-colour spotted cDNA type. In all cases, the patients or arrays had different estimated variances, leading to distinctly unequal weights in the analysis. We suggest also plots which illustrate the variances and correlations that affect the weights computed by our analysis method. For simulated data the improvement relative to previously published methods without weighting is shown to be substantial.

18.
J Allergy Clin Immunol ; 113(6): 1137-43, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15208596

RESUMO

BACKGROUND: Treatment with local glucocorticoids (GCs) decreases symptoms and the size of nasal polyps. This might depend on the downregulation of proinflammatory genes, as well as the upregulation of anti-inflammatory genes. OBJECTIVE: We sought to identify GC-regulated anti-inflammatory genes in nasal polyps. METHODS: Affymetrix DNA microarrays were used to analyze the expression of 22,283 genes in 4 nasal polyps before and after local treatment with fluticasone (400 microg/d). Expression of uteroglobin and mammaglobin B was analyzed with real-time PCR in 6 nasal polyps and in nasal biopsy specimens from 6 healthy control subjects. RESULTS: Two hundred three genes had changed in expression in treated polyps, and 139 had known functions: 54 genes were downregulated, and 85 were upregulated. Genes associated with inflammation constituted the largest single functional group. These genes affected key steps in inflammation (eg, immunoglobulin production; antigen processing and presentation; and the chemoattraction and activation of granulocytes, T cells, and B cells). Several proinflammatory genes were downregulated. In contrast, some anti-inflammatory genes were upregulated. The gene that increased most in terms of expression was uteroglobin. This was confirmed with real-time PCR. By contrast, expression of uteroglobin was lower in untreated polyps than in healthy nasal mucosa. Immunohistochemical investigation showed staining of uteroglobin in the epithelium and in seromucous glands in control subjects and in nasal polyps. CONCLUSION: Upregulation of anti-inflammatory genes, such as uteroglobin, might contribute to the effects of local treatment with GCs in nasal polyps.


Assuntos
Anti-Inflamatórios/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Glucocorticoides/farmacologia , Pólipos Nasais/tratamento farmacológico , Pólipos Nasais/metabolismo , Uteroglobina/genética , Adulto , Humanos , Imuno-Histoquímica , Masculino , Mamoglobina B , Pessoa de Meia-Idade , Proteínas da Mielina , Proteínas de Neoplasias , Análise de Sequência com Séries de Oligonucleotídeos , Proteolipídeos , Secretoglobinas , Uteroglobina/análise
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