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1.
Oncogene ; 26(32): 4738-48, 2007 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-17260012

RESUMO

Malignant melanoma is an aggressive, heterogeneous disease where new biomarkers for diagnosis and clinical outcome are needed. We searched for chromosomal aberrations that characterize its pathogenesis using 47 different melanoma cell lines and tiling-resolution bacterial artificial chromosome-arrays for comparative genomic hybridization. Major melanoma genes, including BRAF, NRAS, CDKN2A, TP53, CTNNB1, CDK4 and PTEN, were examined for mutations. Distinct copy number alterations were detected, including loss or gain of whole chromosomes but also minute amplifications and homozygous deletions. Most common overlapping regions with losses were mapped to 9p24.3-q13, 10 and 11q14.1-qter, whereas copy number gains were most frequent on chromosomes 1q, 7, 17q and 20q. Amplifications were delineated to oncogenes such as MITF (3p14), CCND1 (11q13), MDM2 (12q15), CCNE1 (19q12) and NOTCH2 (1p12). Frequent findings of homozygous deletions on 9p21 and 10q23 confirmed the importance of CDKN2A and PTEN. Pair-wise comparisons revealed distinct sets of alterations, for example, mutually exclusive mutations in BRAF and NRAS, mutual mutations in BRAF and PTEN, concomitant chromosome 7 gain and 10 loss and concomitant chromosome 15q22.2-q26.3 gain and 20 gain. Moreover, alterations of the various melanoma genes were associated with distinct chromosomal imbalances suggestive of specific genomic programs in melanoma development.


Assuntos
Aberrações Cromossômicas , Genes Neoplásicos/genética , Melanoma/genética , Neoplasias Cutâneas/genética , Linhagem Celular Tumoral , Análise Mutacional de DNA , Amplificação de Genes , Dosagem de Genes , Genômica , Humanos , Mutação , Análise de Sequência com Séries de Oligonucleotídeos
2.
J Colloid Interface Sci ; 310(2): 369-76, 2007 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-17382954

RESUMO

The adsorption of organic probe molecules on a partly dehydroxylated silica (SiO(2)) surface has been studied in a non-aquatic and non-polar environment. These results were compared to, verified and explained by quantum chemical calculations on the same systems. Since the systems are water free and since the non-polar solvent cyclohexane is used in the experiments, the quantum chemical calculations are well comparable to the experimental results without any additional terms. The characterized surface was found to contain both Lewis acid and Lewis base sites and a good agreement between the experimentally determined and the calculated data was found.

3.
Artigo em Inglês | MEDLINE | ID: mdl-28086261

RESUMO

BACKGROUND: Gastrointestinal symptoms are common in the general population and may originate from disturbances in gut motility. However, fundamental mechanistic understanding of motility remains inadequate, especially of the less accessible regions of the small bowel and colon. Hence, refinement and validation of objective methods to evaluate motility of the whole gut is important. Such techniques may be applied in clinical settings as diagnostic tools, in research to elucidate underlying mechanisms of diseases, and to evaluate how the gut responds to various drugs. A wide array of such methods exists; however, a limited number are used universally due to drawbacks like radiation exposure, lack of standardization, and difficulties interpreting data. In recent years, several new methods such as the 3D-Transit system and magnetic resonance imaging assessments on small bowel and colonic motility have emerged, with the advantages that they are less invasive, use no radiation, and provide much more detailed information. PURPOSE: This review outlines well-established and emerging methods to evaluate small bowel and colonic motility in clinical settings and in research. The latter include the 3D-Transit system, magnetic resonance imaging assessments, and high-resolution manometry. Procedures, indications, and the relative strengths and weaknesses of each method are summarized.


Assuntos
Motilidade Gastrointestinal/fisiologia , Intestino Grosso/diagnóstico por imagem , Intestino Grosso/fisiologia , Intestino Delgado/diagnóstico por imagem , Intestino Delgado/fisiologia , Manometria/métodos , Testes Respiratórios/métodos , Gastroenteropatias/diagnóstico por imagem , Gastroenteropatias/fisiopatologia , Trânsito Gastrointestinal/fisiologia , Humanos , Imageamento por Ressonância Magnética/métodos , Cintilografia/métodos
4.
J Natl Cancer Inst ; 92(15): 1260-6, 2000 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-10922411

RESUMO

BACKGROUND: : Inherited mutations in the CDKN2A tumor suppressor gene, which encodes the p16(INK4a) protein, and in the cyclin-dependent kinase 4 (CDK4) gene confer susceptibility to cutaneous malignant melanoma. We analyzed families with two or more cases of melanoma for germline mutations in CDKN2A and CDK4 to elucidate the contribution of these gene defects to familial malignant melanoma and to the occurrence of other cancer types. METHODS: : The entire CDKN2A coding region and exon 2 of the CDK4 gene of an affected member of each of 52 families from southern Sweden with at least two cases of melanoma in first- or second-degree relatives were screened for mutations by use of polymerase chain reaction-single-strand conformation polymorphism analysis. Statistical tests were two-sided. RESULTS: : CDKN2A mutations were found in 10 (19%) of the 52 families. Nine families carried an identical alteration consisting of the insertion of arginine at position 113 of p16(INK4a), and one carried a missense mutation, in which the valine at position 115 was replaced with a glycine. The 113insArg mutant p16(INK4a) was unable to bind cdk4 and cdk6 in an in vitro binding assay. Six of the 113insArg families had at least one member with multiple primary melanomas; the 113insArg families also had a high frequency of other malignancies-in particular, breast cancer (a total of eight cases compared with the expected 2.1; P =.0014) and pancreatic cancer (a total of six cases compared with the expected 0.16; P<.0001). Families with breast cancer also had a propensity for multiple melanomas in females, suggesting that a sex-dependent factor may modify the phenotypic expression of CDKN2A alterations. CONCLUSIONS: : Our findings confirm that the majority of CDKN2A-associated melanoma families in Sweden are due to a single founder mutation. They also show that families with the CDKN2A 113insArg mutation have an increased risk not only of multiple melanomas and pancreatic carcinoma but also of breast cancer.


Assuntos
Neoplasias da Mama/genética , Melanoma/genética , Mutação , Neoplasias Primárias Múltiplas/genética , Neoplasias Pancreáticas/genética , Neoplasias Cutâneas/genética , Sequência de Aminoácidos , Feminino , Genes p16 , Humanos , Masculino , Dados de Sequência Molecular , Linhagem , Reação em Cadeia da Polimerase/métodos , Polimorfismo Conformacional de Fita Simples , Regiões Promotoras Genéticas/genética , Risco , Fatores Sexuais , Suécia
5.
Neurogastroenterol Motil ; 27(12): 1755-63, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26598050

RESUMO

BACKGROUND: Segmental distribution of colorectal volume is relevant in a number of diseases, but clinical and experimental use demands robust reliability and validity. Using a novel semi-automatic magnetic resonance imaging-based technique, the aims of this study were to describe: (i) inter-individual and intra-individual variability of segmental colorectal volumes between two observations in healthy subjects and (ii) the change in segmental colorectal volume distribution before and after defecation. METHODS: The inter-individual and intra-individual variability of four colorectal volumes (cecum/ascending colon, transverse, descending, and rectosigmoid colon) between two observations (separated by 52 ± 10) days was assessed in 25 healthy males and the effect of defecation on segmental colorectal volumes was studied in another seven healthy males. KEY RESULTS: No significant differences between the two observations were detected for any segments (All p > 0.05). Inter-individual variability varied across segments from low correlation in cecum/ascending colon (intra-class correlation coefficient [ICC] = 0.44) to moderate correlation in the descending colon (ICC = 0.61) and high correlation in the transverse (ICC = 0.78), rectosigmoid (ICC = 0.82), and total volume (ICC = 0.85). Overall intra-individual variability was low (coefficient of variance = 9%). After defecation the volume of the rectosigmoid decreased by 44% (p = 0.003). The change in rectosigmoid volume was associated with the true fecal volume (p = 0.02). CONCLUSIONS & INFERENCES: Imaging of segmental colorectal volume, morphology, and fecal accumulation is advantageous to conventional methods in its low variability, high spatial resolution, and its absence of contrast-enhancing agents and irradiation. Hence, the method is suitable for future clinical and interventional studies and for characterization of defecation physiology.


Assuntos
Colo/anatomia & histologia , Imageamento por Ressonância Magnética/métodos , Adulto , Defecação , Voluntários Saudáveis , Humanos , Masculino , Tamanho do Órgão , Reprodutibilidade dos Testes , Adulto Jovem
6.
J Clin Endocrinol Metab ; 86(4): 1724-30, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11297609

RESUMO

Endometrial angiogenesis is not well studied, but has potential as a model for studies of physiological angiogenesis. Migration as well as proliferation of vascular endothelial cells are modulated by other endometrial cells. This study analyzes the chemotactic signal released from endometrial tissue in a wound assay using human microvascular endothelial cells. Endometrial tissue explants stimulate migration, and this effect is significantly weaker with explants taken at midcycle than those obtained earlier or later in the cycle. Migration is inhibited more than 50% by either blocking antibodies to the urokinase plasminogen activator receptor (uPAR) or enzymatic removal of uPAR from the cell surface. Also, migration is inhibited more than 50% by antibodies to epidermal growth factor (EGF), but not by antibodies to vascular endothelial growth factor or basic fibroblast growth factor. The combination of anti-EGF and anti-uPAR antibodies does not further reduce the response, suggesting that these antibodies target a common pathway. Conditioned medium from endometrial explants contains EGF, and EGF stimulates the migration of endothelial cells in a dose-dependent way. This effect is completely blocked by antibodies to uPAR. These data suggest up-regulation of the uPA system by EGF. Conditioned medium from EGF-treated cells contains less uPA than medium from control cells. In contrast, binding of radiolabeled uPA reveals an increased number of uPA-binding sites in EGF-treated cells. Increased expression of uPAR potentially increases the activation and assembly of focal adhesion sites, a prerequisite for cell migration. We conclude that the endometrial migratory signal has two components. The major part of the signal is blocked by antibodies to EGF, and the response is mediated via up-regulation of uPAR in the endothelial cells. The other part of the signal is unknown, and the response does not involve uPAR. Decreased endometrial chemotactic signal at midcycle is probably related to decreased release of EGF, which is secondary to increased binding to endometrial cell membranes.


Assuntos
Capilares/fisiologia , Endométrio/fisiologia , Endotélio Vascular/fisiologia , Fator de Crescimento Epidérmico/fisiologia , Comunicação Parácrina , Receptores de Superfície Celular/fisiologia , Adulto , Capilares/citologia , Linhagem Celular , Movimento Celular/fisiologia , Fatores Quimiotáticos/fisiologia , Endométrio/irrigação sanguínea , Endotélio Vascular/citologia , Feminino , Humanos , Pessoa de Meia-Idade , Neovascularização Fisiológica/fisiologia , Receptores de Ativador de Plasminogênio Tipo Uroquinase , Regulação para Cima
7.
J Clin Neurophysiol ; 18(1): 68-74, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11290941

RESUMO

The purpose of this study was to investigate a mechanism of action for the effect of vagal nerve stimulation on reducing seizures in patients with complex partial epilepsy. The hypothesis tested was that vagal nerve stimulation has an antikindling effect on epilepsy. The databases of two large clinical trials (E03, E05) were accessed, and statistical methods were applied using logarithmic transforms and regression analysis. Two parameters--duration of a patient's epilepsy before entering the clinical trial and the patient's seizure density before entering the clinical trial--were used as markers of subsequent seizure control during vagal nerve stimulation. In general, there was not a good fit to the regression lines, and the slope of the lines did not conform to the hypothesis. The hypothesis that vagal nerve stimulation may unkindle epileptic seizures was not supported.


Assuntos
Epilepsia Parcial Complexa , Excitação Neurológica , Estimulação Elétrica Nervosa Transcutânea/estatística & dados numéricos , Nervo Vago , Epilepsia Parcial Complexa/terapia , Humanos , Excitação Neurológica/fisiologia , Análise de Regressão , Nervo Vago/fisiologia
8.
Melanoma Res ; 12(6): 549-57, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12459644

RESUMO

Primary cutaneous malignant melanomas (CMMs) from 26 individuals belonging to nine families with an identified mutation were clinically and histopathologically compared with 78 matched CMM controls and with a population-based series of CMMs ( = 667). All tumours were histopathologically re-examined. CDKN2A-associated cases were significantly less invasive compared with the matched controls, with an adjusted odds ratio (adjOR) of 2.9 and a 95% confidence interval (CI) of 1.0-8.1 ( = 0.04). According to the odds ratio (OR) values, CDKN2A-associated cases seemed to have tumours more often located on the head and neck (adjOR 2.9, 95% CI 0.6-13.7), with less inflammation (adjOR 0.7, 95% CI 0.3-1.8) and regression (adjOR 0.6, 95% CI 0.2-1.8) but more frequent histological ulceration (adjOR 1.9, 95% CI 0.6-5.8). In comparison with the population-based material, CDKN2A-associated cases were significantly younger at diagnosis (crude OR 3.5, 95% CI 1.6-7.5, divided at 50 years) and had less regressive reaction in their tumours (crude OR 0.35, 95% CI 0.2-0.8). No significant differences were seen for tumour thickness between the different groups. On multivariate analysis, the overall survival was significantly worse for thicker tumours and older age ( = 0.04 for both). To our knowledge this is the first description of the histopathological features of CMMs from families with mutations in the CDKN2A gene.


Assuntos
DNA de Neoplasias/análise , Genes p16 , Mutação em Linhagem Germinativa , Melanoma/genética , Neoplasias Cutâneas/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Cromossomos Humanos Par 9/genética , Análise Mutacional de DNA , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Análise por Pareamento , Melanoma/epidemiologia , Melanoma/patologia , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/patologia , Análise de Sobrevida , Suécia/epidemiologia
9.
Maturitas ; 34(2): 127-31, 2000 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-10714907

RESUMO

AIMS: the prevalence of urinary tract infections (UTI), urinary incontinence (UI), estrogen-use and overall mortality in a cohort of elderly women who had been treated for UTI in 1985-86 was re-assessed 10 years later. MATERIAL AND METHODS: a random sample of 6000 women from the birth cohorts 1900, 1905, 1910, 1915 and 1920 were invited in 1986 to complete a questionnaire about UTI, UI and estrogen use (response rate 70%; n = 4206). Treatment with antibiotics for UTI during 1985-86 was reported by 688 (17%) women. In 1995 a similar questionnaire was sent to the women from this group who were still alive (n = 434). Mortality in the women with a history of UTI was compared with an aged-matched control group of women who did not have UTI during 1985-86. RESULTS: the questionnaire was completed and returned by 361 (83%) women. Treatment for at least one UTI during the last 9 years was reported by 219 (61%) women. The number of episodes varied: 35% had one to two UTI, 28% had three to four UTI, 27% five to ten UTI and 10% had had more than 10 UTI. In 1986, the prevalence of UI was higher in women with a history of UTI than in the total population sample (30 vs. 17%; P < 0.001). The prevalence of UI had increased from 30% in 1986 to 33% in 1995 (P < 0.05). Mortality in the women with a history of UTI was higher than in the aged-matched control group (37 vs. 28%; P < 0.001). A total of 162 (45%) women had received estrogen therapy at some time after the age of 60 years and 140 (39%) reported that they were currently taking low potency estrogens. CONCLUSION: elderly women with a history of UTI had a continued high occurrence of UTI and UI, and overall mortality was higher in these women than in an age-matched control group of women from the total population.


Assuntos
Infecções Urinárias/epidemiologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/uso terapêutico , Estudos de Casos e Controles , Causas de Morte , Estudos de Coortes , Terapia de Reposição de Estrogênios/estatística & dados numéricos , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Prevalência , Suécia/epidemiologia , Incontinência Urinária/epidemiologia , Infecções Urinárias/mortalidade
10.
Bull Hosp Jt Dis ; 57(2): 69-73, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9725060

RESUMO

The relationship between blood transfusion and postoperative wound infection was studied in 695 operations for cervical hip fractures. A total of 156 (22%) patients were transfused with a total of 392 units of blood. A total of 31 (4.5%) patients developed a postoperative superficial or deep wound infection. Cultures identified Staphylococcus aureus as the cause in 71% and E. coli in 9.7% of the infections. A total of 11 out of 156 (7.05%) transfused patients developed a wound infection. In contrast only 20 out of 539 (3.71%) non-transfused patients developed a wound infection (p < 0.05).


Assuntos
Transfusão de Sangue , Fraturas do Colo Femoral/cirurgia , Infecção da Ferida Cirúrgica/etiologia , Idoso , Idoso de 80 Anos ou mais , Artroplastia de Quadril/instrumentação , Artroplastia de Quadril/métodos , Perda Sanguínea Cirúrgica , Cimentos Ósseos , Parafusos Ósseos , Infecções por Escherichia coli/etiologia , Feminino , Humanos , Masculino , Período Pós-Operatório , Infecções Estafilocócicas/etiologia , Staphylococcus aureus
20.
Hum Reprod ; 22(1): 83-91, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16920725

RESUMO

BACKGROUND: The combined effect from the androgen receptor (AR) CAG and GGC length polymorphisms on testosterone levels has not been studied in young women. METHODS: Testosterone levels were measured in blood drawn on both menstrual cycle days 5-10 and 18-23 in 258 healthy women, aged < or =40 years, from high-risk breast cancer families. CAG and GGC length polymorphisms were analysed by PCR and fragment analyses. All women completed a questionnaire including information on oral contraceptive (OC) use and reproductive factors. RESULTS: OC users had lower median testosterone levels than non-users during cycle days 5-10 and 18-23 (P < or = 0.005 for both). The BRCA mutation status was associated neither with testosterone levels nor with CAG or GGC length polymorphism. The CAG length polymorphism was not associated with testosterone levels. The cumulative number of long GGC alleles (> or =17 repeats) was significantly associated with lower testosterone levels in OC users during cycle days 5-10 (P(trend) =0.014), but not during cycle days 18-23 or in non-users. The interaction between the GGC length polymorphism and OC status was highly significant during cycle days 5-10 (P = 0.002) and near-significant during days 18-23 (P = 0.07). Incident breast cancer was more common in women with two short GGC alleles (log-rank P = 0.003). CONCLUSION: The GGC repeat length was the only significant genetic factor modifying the testosterone levels in current OC users from high-risk families. Homozygosity for the short GGC allele may be linked to the increased risk of early-onset breast cancer after OC exposure in high-risk women.


Assuntos
Anticoncepcionais Orais/uso terapêutico , Polimorfismo Genético , Receptores Androgênicos/genética , Testosterona/sangue , Adulto , Neoplasias da Mama/etiologia , Estudos de Coortes , Feminino , Frequência do Gene , Genes BRCA1 , Humanos , Ciclo Menstrual/sangue , Sequências Repetitivas de Ácido Nucleico , Risco , Suécia
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