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1.
Clin Oral Investig ; 19(4): 823-30, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25096672

RESUMO

OBJECTIVES: Sprays containing fine and ultrafine particles are commonly used for optical scanning. The aim of this study was to measure the particle exposure of patient and dentist during application of scanning spray and to evaluate measures for its reduction. MATERIALS AND METHODS: A lower molar in a dental simulator was powdered with scanning spray. Patient's particle exposure was measured by a condensation particle counter in the nasal region of the simulator without (P) and with rubber dam (PC). Dentist's exposure (D) was measured behind a surgical mask. Particle concentrations were determined 5-fold without suction (NS), using conventional dental suction (CDS), or high volume evacuation (HVE). RESULTS: Mean background air particle concentrations for the patient were 3.3 × 10(3) and 1.3 × 10(3) pt/cm(3) for the dentist. Particle concentrations increased after spraying; mean cumulated additional particle exposures for the patient were the following: P-NS 7.2 × 10(6), P-CDS 4.6 × 10(6), P-HVE 2.4 × 10(4); using rubber dam: PC-NS 3.6 × 10(6), PC-CDS 3.3 × 10(5), PC-HVE 2.2 × 10(5). The particle exposures of the dentist were the following: D-NS 9.7 × 10(5), D-CDS 1.8 × 10(5), D-HVE 1.6 × 10(4). CONCLUSIONS: The use of HVE is recommended to reduce exposure of patients and dental staff to fine and ultrafine particles when using scanning sprays. CLINICAL RELEVANCE: Effective protection is available for staff and patient by means of high volume evacuation. In patients suffering from obstructive lung diseases, the use of scanning sprays should be avoided altogether.


Assuntos
Poeira , Modelos Dentários , Exposição Ocupacional/análise , Exposição Ocupacional/normas , Auxiliares de Odontologia , Odontólogos , Pessoal de Saúde , Humanos , Dente Molar/cirurgia , Titânio
2.
PLoS One ; 9(2): e88177, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24516607

RESUMO

BACKGROUND: Antibodies against citrullinated proteins (ACPA) have been recognised as the most specific serum marker for rheumatoid arthritis. However, serum autoantibodies such as anti-nuclear antibodies have also been detected in the sera of different lymphatic malignancies without accompanying rheumatologic disease. Therefore, we conducted a study to evaluate the prevalence of ACPA in diffuse large B-cell non-Hodgkin lymphoma (DLBCL). METHODS: Sera of 395 DLBCL patients and 258 age-matched healthy controls were investigated to evaluate the prevalence of ACPA and RF. ACPA-positive data were stratified into subgroups of RF positivity and established prognostic parameters for DLBCL, including overall survival. In addition, the ACPA serum concentrations levels were compared to an ACPA-positive RA cohort (n = 175). The statistics were performed with χ2 test and Mann- Whitney-U test; Kaplan-Meyer curves (log rank test) were used to analyse the overall survival. P-value <0.05 was statistically significant. RESULTS: ACPA, but not RF, occurred significantly more frequently in the sera of DLBCL patients than in healthy controls (3.5% versus 0.8%, p = 0.030). However, the ACPA serum concentration levels were significantly lower than in RA patients (median 10.4 versus 124.1 U/ml, p = 0.0001). After subgroup stratification, ACPA positivity in DLBCL was significantly associated with male gender (4.4% versus 0%, p = 0.022; odds ratio 1.046, CI 1.014-1.079) and with RF-IgM seropositivity (1.77% versus 0%, p = 0.043), but not with prognostic parameters for DLBCL. CONCLUSIONS: DLBCL is associated with a significantly higher prevalence of ACPA, with an increased prevalence in male patients, and simultaneous RF-IgM positivity. However, ACPA is not prognostic for DLBCL. The prevalence of RF-IgM, -IgA, or -IgG did not differ from healthy controls.


Assuntos
Autoanticorpos/sangue , Linfoma Difuso de Grandes Células B/imunologia , Peptídeos Cíclicos/imunologia , Estudos de Casos e Controles , Feminino , Humanos , Linfoma Difuso de Grandes Células B/sangue , Linfoma Difuso de Grandes Células B/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Soroepidemiológicos , Taxa de Sobrevida
3.
Arthritis Res Ther ; 15(6): R211, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24321127

RESUMO

INTRODUCTION: Psoriatic arthritis (PsA) is a distinctive inflammatory arthritis which may typically develop in a subgroup of individuals suffering from psoriasis. We recently described progranulin autoantibodies (PGRN-Abs) in the sera of patients with different autoimmune diseases including seronegative polyarthritis. In the present study we investigated the occurrence of PGRN-Abs in PsA. METHODS: PGRN-Abs were determined in 260 patients with PsA, 100 patients with psoriasis without arthritic manifestations (PsC) and 97 healthy controls using a recently described ELISA. PGRN plasma levels were determined from subgroups by a commercially available ELISA-kit. Possible functional effects of PGRN-antibodies were analysed in vitro by tumour necrosis factor (TNF)-α mediated cytotoxicity assays using WEHI-S and HT1080 cells. RESULTS: PGRN-Abs were detected with relevant titres in 50/260 (19.23%) patients with PsA, but in 0/100 patients with psoriasis without arthritic manifestations (P = 0.0001). All PGRN-Abs belonged to immunoglobulin G (IgG). PGRN-Abs were significantly more frequent in PsA patients with enthesitis or dactylitis. PGRN-Abs were also more frequent in PsA patients receiving treatment with TNF-α-blockers than in patients treated without TNF-α-blockers (20.8% versus 17.4%; P = 0.016). PGRN plasma levels were significantly lower in PGRN-Ab-positive patients with PsA than in healthy controls and patients with psoriasis without arthritic manifestations (P < 0.001), indicating a neutralizing effect of PGRN-Abs. Moreover cytotoxicity assays comparing PGRN-antibody positive with negative sera from matched patients with PsA, clearly showed a proinflammatory effect of PGRN antibodies. CONCLUSION: Neutralizing PGRN-Abs occur with relevant titres in a subgroup of patients with PsA, but not in patients without arthritic manifestations (PsC). PGRN-Ab-positive patients had more frequent enthesitis or dactylitis. TNF-α-induced cytotoxicity assays demonstrated that the protective effects of progranulin were inhibited by serum containing PGRN-Abs. This suggests that PGRN-Ab might not only be useful as a diagnostic and prognostic marker, but may provide a proinflammatory environment in a subgroup of patients with PsA.


Assuntos
Artrite Psoriásica/sangue , Artrite Psoriásica/imunologia , Autoanticorpos/sangue , Autoanticorpos/imunologia , Peptídeos e Proteínas de Sinalização Intercelular/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Autoantígenos/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Progranulinas , Adulto Jovem
4.
J Orthop Res ; 31(11): 1772-9, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23813860

RESUMO

Associations between topographic location and articular cartilage repair in preclinical animal models are unknown. Based on clinical investigations, we hypothesized that lesions in the ovine femoral condyle repair better than in the trochlea. Full-thickness chondral and osteochondral defects were simultaneously established in the weightbearing area of the medial femoral condyle and the lateral trochlear facet in sheep, with chondral defects subjected to subchondral drilling. After 6 months in vivo, cartilage repair and osteoarthritis development was evaluated by macroscopic, histological, immunohistochemical, and biochemical analyses. Macroscopic and histological articular cartilage repair and type-II collagen immunoreactivity were better in the femoral trochlea, regardless of the defect type. Location-independently, osteochondral defects induced more osteoarthritic degeneration of the adjacent cartilage than drilled chondral lesions. DNA and proteoglycan contents of chondral defects were higher in the condyle, reflecting physiological topographical differences. The results indicate that topographic location dictates the structural patterns and biochemical composition of the repair tissue in sheep. These findings suggest that repair of cartilage defects at different anatomical sites of the ovine stifle joint needs to be assessed independently and that the sheep trochlea exhibits cartilage repair patterns reflective of the human medial femoral condyle.


Assuntos
Cartilagem Articular/cirurgia , Fêmur/cirurgia , Animais , Cartilagem Articular/patologia , Colágeno/análise , Fêmur/patologia , Proteoglicanas/análise , Ovinos , Joelho de Quadrúpedes/cirurgia
5.
Clin Epigenetics ; 5(1): 7, 2013 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-23638630

RESUMO

INTRODUCTION: DNA methylation of CpG islands within the promoter region of genes is an epigenetic modification with an important role in the development of cancer and it is typically mediated by DNA methyltransferases (DNMTs). In cancer cells, global hypomethylation of the genome as a whole and regional hypermethylation of CpG islands have been reported. Four groups of DNMTs have been identified: DNMT1, DNMT2 (TRDMT1), DNMT3A and DNMT3B. DNMT2 uses the catalytic mechanism of DNMTs, but does in fact methylate RNA. Little is known about the significance of these genes in human breast cancer. In the study presented herein, we analyzed five distinct DNMT single SNPs with regard to potential associations with breast cancer risk. CASE DESCRIPTION: In this study, we genotyped 221 female Caucasian breast cancer patients and 221 female Caucasian healthy controls, and we used five allele-specific real-time polymerase chain reaction (qPCR) assays. We selected one locus within the DNMT1 gene and two loci within the DNMT3A and DNMT3B genes, respectively. Statistics were calculated using the chi-squared and Fisher's exact tests, and correlated with clinical parameters such as age, diagnosis, histology, TNM stage, hormonal receptor status, human epidermal growth factor receptor 2 (HER2) status, response to treatment and survival. Statistically significant results were obtained for correlations with the DNMT1 gene. DISCUSSION AND EVALUATION: Five genomic loci within the DNMT1, DNMT3A and DNMT3B genes were assessed. Statistical significance (P = 0.030) was identified for DNMT1 SNP (A201G, rs2228612): six women within the control group were GG homozygous (variant), while this mutation was absent in the breast cancer group. CONCLUSIONS: We conclude that women with the DNMT1 SNP (A201G, rs2228612) GG homozygous genotype (variant) have a lower risk of developing breast cancer compared to heterozygous or wildtype genotypes. To date, alterations within the DNMT1 gene have not been reported to be associated with cancer in the Caucasian population.

6.
Int J Clin Exp Med ; 6(4): 282-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23641305

RESUMO

Estrogen and progesterone hormones are key regulators of a wide variety of biological processes. In addition to their influence on reproduction, cell differentiation and apoptosis, they affect inflammatory response, cell metabolism and most importantly, they regulate physiological breast tissue proliferation and differentiation as well as the development and progression of breast cancer. In order to assess whether genetic variants in the steroid hormone receptor gene ESR1 (estrogen receptor alpha) had an effect on sporadic breast cancer susceptibility, we assessed 7 ESR1 single nucleotide polymorphisms (SNPs) for associations with breast cancer susceptibility and clinical parameters in 221 breast cancer patients and 221 controls, respectively. We identified ESR1 intron SNP +2464 C/T (rs3020314) and ESR1 intron SNP -4576 A/C (rs1514348) to correlate with breast cancer susceptibility and progesterone receptor expression status. Patients genotyped CT for ESR1 intron SNP +2464 (rs3020314) (p ≤ 0.045) or genotyped AC for ESR1 intron SNP -4576 (rs1514348) (p ≤ 0.000026) were identified to carry a significant risk as to the development of breast cancer in the Central European Caucasian population (both together: p ≤ 0.000488). Our study could confirm previous associations and revealed new associations of SNP rs1514348 with susceptibility to breast cancer and clinical outcome, which might be used as new additional SNP markers.

7.
Breast Cancer (Auckl) ; 7: 35-40, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23515655

RESUMO

AIM: To assess the diagnostic value of pre-surgery axillary ultrasound for nodal staging in patients with primary breast cancer and to identify clinical/histopathological factors impacting diagnostic performance. STUDY DESIGN: Single-center, retrospective chart analysis. We assessed sensitivity, specificity, and positive and negative predictive value of clinical examination as well as axillary ultrasound vs. clinical examination alone. The histopathological results were the standard of truth. In addition, we analyzed clinical and histopathological factors regarding their potential to impact sensitivity and specificity. RESULTS: We enrolled a total of 172 women in the study. Sensitivity of clinical examination plus ultrasound was significantly higher than for clinical examination alone (58% vs. 31.6%). Specificity and positive predictive value were similar while the negative predictive value increased from 63.4% to 73% when additionally applying ultrasound. Sensitivity and specificity of axillary ultrasound were impacted by tumor size (P = 0.2/0.04), suspicious axillary palpation (P < 0.01/<0.01), number of affected lymph nodes (P < 0.01/-) and distant metastases (P = 0.04/<0.01). All other factors had no impact. CONCLUSION: Since pre-surgery axillary nodal staging is currently used to determine disease management, axillary ultrasound is a useful add-on tool in the diagnostic armamentarium for breast cancer patients. Tumor size, suspicious axillary palpation, number of affected lymph nodes and distant metastases increase diagnostic performance of this diagnostic modality.

8.
Knee Surg Sports Traumatol Arthrosc ; 21(1): 39-48, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22898914

RESUMO

PURPOSE: To evaluate whether medial open wedge high tibial osteotomy (HTO) results in structural and biochemical changes in the lateral meniscus in adult sheep. METHODS: Three experimental groups with biplanar osteotomies of the right proximal tibiae were tested: (a) closing wedge HTO resulting in 4.5° of tibial varus, (b) open wedge HTO resulting in 4.5° of tibial valgus (standard correction) and (c) open wedge HTO resulting in 9.5° of valgus (overcorrection), each of which was compared to the contralateral knees with normal limb axes. After 6 months, the lateral menisci were macroscopically and microscopically evaluated. The proteoglycan and DNA contents of the red-red and white-white zones of the anterior, middle and posterior third were determined. RESULTS: Semiquantitative macroscopic and microscopic grading revealed no structural differences between groups. The red-red zone of the middle third of the lateral menisci of animals that underwent overcorrection exhibited a significant 0.7-fold decrease in mean DNA contents compared with the control knee without HTO (P = 0.012). Comparative estimation of the DNA and proteoglycan contents and proteoglycan/DNA ratios of all other parts and zones of the lateral menisci did not reveal significant differences between groups. CONCLUSION: Open wedge HTO does not lead to significant macroscopic and microscopic structural changes in the lateral meniscus after 6 months in vivo. Overcorrection significantly decreases the proliferative activity of the cells in the red-red zone of the middle third in the sheep model.


Assuntos
Meniscos Tibiais/patologia , Osteotomia/efeitos adversos , Tíbia/cirurgia , Animais , Biomarcadores/metabolismo , Mau Alinhamento Ósseo/etiologia , Mau Alinhamento Ósseo/metabolismo , Mau Alinhamento Ósseo/patologia , DNA/metabolismo , Meniscos Tibiais/metabolismo , Osteotomia/métodos , Proteoglicanas/metabolismo , Ovinos
9.
Swiss Med Wkly ; 142: w13625, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22782255

RESUMO

BACKGROUND AND STUDY PURPOSE: High resolution imaging modalities and electroencephalographic studies (EEG) are used in the assessment of children with headaches. We evaluated the role of cerebral MRI (cMRI) and EEG in the initial assessment of children with headache as the chief complaint of initial presentation. METHODS: A retrospective chart analysis was performed at a tertiary University Hospital. RESULTS: 209 patients were included in this study [mean age 11.3 years; male 91 (43.5%); female 118 (56.5%)]. The following types of headaches were seen: Unclassified headache: 23.4%; probable migraine 17.2%, migraine without aura 13.4%, complicated migraine 12.4%, migraine with aura 1.0%; tension-type 15.3%, and cluster headaches 0.5%, and secondary headaches 16.7%. In 93 children (44.5%) abnormal physical/neurological findings were noted (multiple entries possible). On cMRI studies the following findings were seen: Infection of sinuses (7.2%), pineal cysts (2.4%), arachnoidial cyst and Chiari malformation (1.9%), unspecified signal enhancement (1.0%), and pituitary enlargement, inflammatory lesion, angioma, cerebral ischaemia, and intra-cerebral cyst (each 0.5%). Electroencephalographic findings included both focal and generalised abnormal slowing (5.3%) and Spike-wave complexes (3.3%). CONCLUSIONS: Despite abnormal findings on neurological/physical examination in a substantial number of children with headaches, the yield of pathological cMRIs was low. The use of EEG recordings was not contributory to the diagnostic and therapeutic approach. More research is needed to better define those patients who are likely to have an intracranial pathology.


Assuntos
Neoplasias Encefálicas/diagnóstico , Eletroencefalografia , Transtornos da Cefaleia Primários/diagnóstico , Cefaleia/etiologia , Hemangioma/diagnóstico , Imageamento por Ressonância Magnética , Adolescente , Cistos Aracnóideos/complicações , Cistos Aracnóideos/diagnóstico , Malformação de Arnold-Chiari/complicações , Malformação de Arnold-Chiari/diagnóstico , Isquemia Encefálica/complicações , Isquemia Encefálica/diagnóstico , Neoplasias Encefálicas/complicações , Criança , Pré-Escolar , Cefaleia Histamínica/complicações , Cefaleia Histamínica/diagnóstico , Diagnóstico Diferencial , Feminino , Transtornos da Cefaleia Primários/complicações , Hemangioma/complicações , Humanos , Masculino , Enxaqueca com Aura/complicações , Enxaqueca com Aura/diagnóstico , Enxaqueca sem Aura/complicações , Enxaqueca sem Aura/diagnóstico , Neuroimagem , Exame Neurológico , Estudos Retrospectivos , Cefaleia do Tipo Tensional/complicações , Cefaleia do Tipo Tensional/diagnóstico
10.
Am J Sports Med ; 40(4): 828-36, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22223716

RESUMO

BACKGROUND: Marrow stimulation techniques such as subchondral drilling are clinically important treatment options for symptomatic small cartilage defects. Little is known about whether they induce deleterious changes in the subchondral bone. HYPOTHESIS: Subchondral drilling induces substantial alterations of the microarchitecture of the subchondral bone that persist for a clinically relevant postoperative period in a preclinical large animal model. STUDY DESIGN: Controlled laboratory study. METHODS: Standardized full-thickness chondral defects in the medial femoral condyles of 19 sheep were treated by subchondral drilling. Six months postoperatively, the formation of cysts and intralesional osteophytes was evaluated. A standardized methodology was developed to segment the ovine subchondral unit into reproducible volumes of interest (VOIs). Indices of bone structure were determined by micro-computed tomography (micro-CT). RESULTS: Analysis of the microarchitecture revealed the absence of zonal stratification in the ovine subarticular spongiosa, permitting an unimpeded and simultaneous analysis of the entire subchondral trabecular network. Subchondral drilling led to the formation of subchondral bone cysts (63%) and intralesional osteophytes (26%). Compared with the adjacent unaffected subchondral bone, drilling induced significant alterations in nearly all parameters for the microarchitecture of the subchondral bone plate and the subarticular spongiosa, most importantly in bone volume, bone surface/volume ratio, trabecular thickness, separation, pattern factor, and bone mineral density (BMD) (all P ≤ .01). CONCLUSION: The data show that the ovine subchondral bone can be reliably evaluated using micro-CT with standardized VOIs. We report that subchondral drilling deteriorates the microarchitecture both of the subchondral bone plate and subarticular spongiosa and decreases BMD. These results suggest that the entire osteochondral unit is altered after drilling for an extended postoperative period. CLINICAL RELEVANCE: The subchondral bone remains fragile after subchondral drilling for longer durations than previously expected. Further evaluations of structural subchondral bone parameters of patients undergoing marrow stimulation are warranted.


Assuntos
Artroplastia Subcondral/métodos , Osso e Ossos/cirurgia , Osso e Ossos/ultraestrutura , Animais , Artroplastia Subcondral/efeitos adversos , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/fisiopatologia , Alemanha , Modelos Animais , Avaliação de Resultados em Cuidados de Saúde , Ovinos , Tomografia Computadorizada por Raios X
11.
FEMS Immunol Med Microbiol ; 62(1): 23-31, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21251089

RESUMO

The extracellular adherence protein (Eap) from Staphylococcus aureus has been suggested as a vaccine candidate and for therapeutic use due to its immunomodulating and antiangiogenic properties; however, little is known about anti-Eap antibodies in humans. We determined anti-Eap antibody titers by enzyme-linked immunosorbent assay and Western blot and measured serum samples from 92 patients with proven S. aureus infections and 93 healthy controls. The functionality of antibodies was assessed by a phagocytosis assay using Eap-coated fluorescent microspheres. Antibodies were detected in all human samples, but not in mice. Patients showed significantly higher titers than controls [immunoglobulin M (IgM), P=0.007; IgG, P<0.0001]. Patients with deep or severe infections showed higher titers than those with superficial or mild disease. Eap alone was sufficient to promote phagocytosis by peripheral blood mononuclear cell and granulocytes that was moderately enhanced in the presence of human serum, but no correlation was found with the levels of anti-Eap antibodies. Anti-Eap antibodies are prevalent in all tested humans and correlate with the severity of S. aureus infection; however, they do not seem to provide protection against invasive infections. Before considering Eap for therapy or as a vaccine candidate, further studies are warranted to assess the impact of the interference between Eap and its specific antibodies.


Assuntos
Anticorpos Antibacterianos/sangue , Proteínas de Bactérias/imunologia , Proteínas de Ligação a RNA/imunologia , Infecções Estafilocócicas/imunologia , Infecções Estafilocócicas/fisiopatologia , Staphylococcus aureus/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Western Blotting , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Fagocitose , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/metabolismo , Adulto Jovem
12.
Circulation ; 121(14): 1606-13, 2010 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-20351235

RESUMO

BACKGROUND: Oxidative stress is causally linked to the progression of heart failure, and mitochondria are critical sources of reactive oxygen species in failing myocardium. We previously observed that in heart failure, elevated cytosolic Na(+) ([Na(+)](i)) reduces mitochondrial Ca(2+) ([Ca(2+)](m)) by accelerating Ca(2+) efflux via the mitochondrial Na(+)/Ca(2+) exchanger. Because the regeneration of antioxidative enzymes requires NADPH, which is indirectly regenerated by the Krebs cycle, and Krebs cycle dehydrogenases are activated by [Ca(2+)](m), we speculated that in failing myocytes, elevated [Na(+)](i) promotes oxidative stress. METHODS AND RESULTS: We used a patch-clamp-based approach to simultaneously monitor cytosolic and mitochondrial Ca(2+) and, alternatively, mitochondrial H(2)O(2) together with NAD(P)H in guinea pig cardiac myocytes. Cells were depolarized in a voltage-clamp mode (3 Hz), and a transition of workload was induced by beta-adrenergic stimulation. During this transition, NAD(P)H initially oxidized but recovered when [Ca(2+)](m) increased. The transient oxidation of NAD(P)H was closely associated with an increase in mitochondrial H(2)O(2) formation. This reactive oxygen species formation was potentiated when mitochondrial Ca(2+) uptake was blocked (by Ru360) or Ca(2+) efflux was accelerated (by elevation of [Na(+)](i)). In failing myocytes, H(2)O(2) formation was increased, which was prevented by reducing mitochondrial Ca(2+) efflux via the mitochondrial Na(+)/Ca(2+) exchanger. CONCLUSIONS: Besides matching energy supply and demand, mitochondrial Ca(2+) uptake critically regulates mitochondrial reactive oxygen species production. In heart failure, elevated [Na(+)](i) promotes reactive oxygen species formation by reducing mitochondrial Ca(2+) uptake. This novel mechanism, by which defects in ion homeostasis induce oxidative stress, represents a potential drug target to reduce reactive oxygen species production in the failing heart.


Assuntos
Cálcio/metabolismo , Mitocôndrias/fisiologia , Miócitos Cardíacos/metabolismo , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Sódio/metabolismo , Animais , Citosol/metabolismo , Cobaias , Peróxido de Hidrogênio/metabolismo , Cinética , Potenciais da Membrana/fisiologia , Membranas Mitocondriais/fisiologia , NAD/metabolismo , NADP/metabolismo , Oxirredução , Fosforilação Oxidativa , Técnicas de Patch-Clamp
13.
Int J Radiat Oncol Biol Phys ; 76(4): 1206-13, 2010 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-20206019

RESUMO

PURPOSE: There is increasing evidence that genetic factors regulating the recognition and/or repair of DNA double-strand breaks (DSBs) are responsible for differences in radiosensitivity among patients. Genetically defined DSB repair capacities are supposed to determine patients' individual susceptibility to develop adverse normal tissue reactions after radiotherapy. In a preclinical murine model, we analyzed the impact of different DSB repair capacities on the cumulative DNA damage in normal tissues during the course of fractionated irradiation. MATERIAL AND METHODS: Different strains of mice with defined genetic backgrounds (SCID(-/-) homozygous, ATM(-/-) homozygous, ATM(+/-)heterozygous, and ATM(+/+)wild-type mice) were subjected to single (2 Gy) or fractionated irradiation (5 x 2 Gy). By enumerating gammaH2AX foci, the formation and rejoining of DSBs were analyzed in organs representative of both early-responding (small intestine) and late-responding tissues (lung, kidney, and heart). RESULTS: In repair-deficient SCID(-/-) and ATM(-/-)homozygous mice, large proportions of radiation-induced DSBs remained unrepaired after each fraction, leading to the pronounced accumulation of residual DNA damage after fractionated irradiation, similarly visible in early- and late-responding tissues. The slight DSB repair impairment of ATM(+/-)heterozygous mice was not detectable after single-dose irradiation but resulted in a significant increase in unrepaired DSBs during the fractionated irradiation scheme. CONCLUSIONS: Radiation-induced DSBs accumulate similarly in acute- and late-responding tissues during fractionated irradiation, whereas the whole extent of residual DNA damage depends decisively on the underlying genetically defined DSB repair capacity. Moreover, our data indicate that even minor impairments in DSB repair lead to exceeding DNA damage accumulation during fractionated irradiation and thus may have a significant impact on normal tissue responses in clinical radiotherapy.


Assuntos
Quebras de DNA de Cadeia Dupla , Reparo do DNA/genética , Fracionamento da Dose de Radiação , Tolerância a Radiação/genética , Animais , Proteínas Mutadas de Ataxia Telangiectasia , Proteínas de Ciclo Celular/genética , Proteínas de Ligação a DNA/genética , Coração/efeitos da radiação , Heterozigoto , Histonas/genética , Homozigoto , Intestino Delgado/efeitos da radiação , Rim/efeitos da radiação , Pulmão/efeitos da radiação , Camundongos , Camundongos SCID , Proteínas Serina-Treonina Quinases/genética , Proteínas Supressoras de Tumor/genética
15.
Oncol Rep ; 23(1): 263-9, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19956891

RESUMO

HDAC inhibitors (HDACi) are gaining increasing attention in the treatment of cancer, particularly in view of their therapeutic effectiveness and assumed mild toxicity profile. While numerous studies have investigated the role of HDACi in tumor cells, little is known about their effects on normal tissue cells. We studied the effect of suberoylanilide hydroxamic acid (SAHA), MS275, sodium-butyrate and valproic acid in healthy human fibroblasts and found HDACi-treatment to go along with increased radiosensitivity and reduced DSB repair capacity. In view of the potential genotoxic effects of HDACi-treatment, particularly when being administered long-term for chronic disease or when given to children, to women of childbearing age or their partners or in combination with radiotherapy, an extensive education of patients and prescribing physicians as well as a stringent definition of clinical indications is urgently required.


Assuntos
Quebras de DNA de Cadeia Dupla , Reparo do DNA , Histona Desacetilases/metabolismo , Benzamidas/farmacologia , Proliferação de Células , Relação Dose-Resposta à Radiação , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Ácidos Hidroxâmicos/farmacologia , Microscopia de Fluorescência/métodos , Piridinas/farmacologia , Transdução de Sinais , Oxibato de Sódio/farmacologia , Fatores de Tempo , Ácido Valproico/farmacologia , Vorinostat
16.
Am J Clin Nutr ; 90(5): 1440-5, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19759168

RESUMO

BACKGROUND: Several clinical trials have reported B vitamins to be associated with osteoporosis. OBJECTIVE: Our objective was to investigate whether low serum B vitamins are associated with altered structural and biomechanical properties of human bone. DESIGN: Femoral heads of 94 men and women who underwent hip arthroplasty were analyzed by using dual-energy X-ray absorptiometry (DXA), biomechanical testing (indentation method), and histomorphometry. In addition, blood was collected to measure serum concentrations of homocysteine, folate, vitamin B-6, vitamin B-12, the bone formation marker osteocalcin, and the bone resorption marker tartrate-resistant acid phosphatase (TRAP). Measurement outcomes were grouped according to subjects with high and low serum concentrations, respectively, of folate, vitamin B-6, and vitamin B-12 (n = 47 for each group). RESULTS: Histomorphometric analysis showed a significantly lower trabecular thickness and trabecular area in subjects with low serum folate concentrations than in those with high serum folate concentrations and a significantly lower trabecular number in subjects with low serum vitamin B-6 concentrations than in those with high serum vitamin B-6 concentrations. In contrast, we found a comparable trabecular structure in subjects with high and low serum vitamin B-12 concentrations. DXA and biomechanical testing did not show significant differences between subjects with high and low serum B vitamin concentrations. Osteocalcin was significantly lowered in subjects with a low serum B vitamin concentration, whereas there was no association between serum B vitamins and TRAP. CONCLUSION: The results of the present study indicate that low serum folate and vitamin B-6 concentrations, but not low serum vitamin B-12 concentrations, are associated with an altered morphology of human bone.


Assuntos
Artroplastia de Quadril/métodos , Densidade Óssea , Osso e Ossos/patologia , Cabeça do Fêmur/patologia , Deficiência de Ácido Fólico/sangue , Deficiência de Vitamina B 6/sangue , Absorciometria de Fóton , Idoso , Estatura , Peso Corporal , Feminino , Ácido Fólico/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/sangue , Vitamina B 12/sangue , Deficiência de Vitamina B 12/sangue
17.
Eur J Obstet Gynecol Reprod Biol ; 146(1): 37-40, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19560853

RESUMO

OBJECTIVE: To assess the effects of heavy and very heavy smoking on the rate of small for gestational age (SGA) infants, and to assess socio-economic and regional differences in smoking patterns in pregnant women in Germany. STUDY DESIGN: The Neonatal and Perinatal database of the federal state of Saarland, Germany was used to perform a population-based analysis of preterm (>32 weeks of gestation) and term (>36 weeks of gestation) newborns in 2004-2006. The rate of SGA babies dependent on the amount of tobacco exposure among self-identified smokers and non-smokers were assessed, and distinct maternal risk factors for smoking were evaluated. Our data were compared with the German National Perinatal database. RESULTS: 14,593 paired data sets (peripartum/perinatal) were included in this study. The overall rate of smoking during pregnancy was 11.8% with a high percentage of pregnant women smoking 11-20 cigarettes/day (heavy smoker; 4.0%), and >20 cigarettes/day (very heavy smoker; 0.6%). Self-identified heavy tobacco use significantly increased the risk for SGA infants (p<0.01) in women without uteroplacental insufficiency. Risk factors for smoking included ethnicity (German/Caucasian), socio-economic parameters (single vs. non-single households, status of employment) and age. Smoking pattern and the rate of SGA babies in our cohort differed substantially from the national average. CONCLUSIONS: Although the overall rate of smoking appears comparable to previously published data, heavy and very heavy smoking was high in our cohort. Heavy smoking was disproportionately associated with SGA. Preventative measures and strategies should take into consideration socio-economic risk factors as well as regional differences, and should be targeted at distinct subgroups that are especially prone to smoking during pregnancy.


Assuntos
Recém-Nascido Pequeno para a Idade Gestacional , Exposição Materna/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal , Fumar/efeitos adversos , Adulto , Feminino , Alemanha/epidemiologia , Humanos , Recém-Nascido , Masculino , Insuficiência Placentária/epidemiologia , Gravidez , Fatores Socioeconômicos
18.
Gastroenterology ; 134(4): 960-74, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18395077

RESUMO

BACKGROUND & AIMS: Transient elastography has been studied in a multitude of liver diseases for the staging of liver fibrosis with variable results. A meta-analysis was performed to assess the overall performance of transient elastography for the diagnosis of liver fibrosis and to analyze factors influencing the diagnostic accuracy. METHODS: Literature databases and international conference abstracts were searched. Inclusion criteria were as follows: evaluation of transient elastography, liver biopsy as reference, and assessment of the area under the receiver operating characteristic curve (AUROC). The meta-analysis was performed using the random-effects model for the AUROC, summary receiver operating curve techniques, as well as meta-regression approaches. RESULTS: Fifty studies were included in the analysis. The mean AUROC for the diagnosis of significant fibrosis, severe fibrosis, and cirrhosis were 0.84 (95% confidence interval [CI], 0.82-0.86), 0.89 (95% CI, 0.88-0.91), and 0.94 (95% CI, 0.93-0.95), respectively. For the diagnosis of significant fibrosis a significant reduction of heterogeneity of the AUROC was found when differentiating between the underlying liver diseases (P < .001). Other factors influencing the AUROC were the scoring system used and the country in which the study was performed. Age, body mass index, and biopsy quality did not have a significant effect on the AUROC. CONCLUSIONS: Transient elastography can be performed with excellent diagnostic accuracy and independent of the underlying liver disease for the diagnosis of cirrhosis. However, for the diagnosis of significant fibrosis, a high variation of the AUROC was found that is dependent on the underlying liver disease.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Cirrose Hepática/diagnóstico , Diagnóstico Diferencial , Humanos , Cirrose Hepática/fisiopatologia , Curva ROC , Reprodutibilidade dos Testes , Índice de Gravidade de Doença
19.
AJR Am J Roentgenol ; 188(3): 758-64, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17312065

RESUMO

OBJECTIVE: Recently, transient elastography (FibroScan) has been introduced for noninvasive staging of liver fibrosis. Here, we investigated a novel approach for noninvasive assessment of liver fibrosis using sonography-based real-time elastography, which can be performed with conventional ultrasound probes during a routine sonography examination. MATERIALS AND METHODS: Real-time elastography was performed in 79 patients with chronic viral hepatitis and known fibrosis stage and in 20 healthy volunteers. A specially developed program was used for quantification of tissue elasticity. Stepwise logistic regression analysis was performed to define an elasticity score using variables with high reproducibility in a preceding analysis of data from 16 different patients. In addition, aspartate transaminase-to-platelet ratio index (APRI) and routine laboratory values were included in the analysis. RESULTS: The Spearman's correlation coefficient between the elasticity scores obtained using real-time elastography and the histologic fibrosis stage was 0.48, which is highly significant (p < 0.001). The diagnostic accuracy expressed as areas under receiver operating characteristic (ROC) curves were 0.75 for the diagnosis of significant fibrosis (fibrosis stage according to METAVIR scoring system [F] > or = F2), 0.73 for severe fibrosis (F > or = F3), and 0.69 for cirrhosis. For a combined elasticity-laboratory score, the areas under the ROC curves were 0.93, 0.95, and 0.91, respectively. DISCUSSION: Real-time elastography is a new and promising sonography-based noninvasive method for the assessment of liver fibrosis in patients with chronic viral hepatitis.


Assuntos
Hepatite Viral Humana/complicações , Hepatite Viral Humana/diagnóstico por imagem , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico por imagem , Ultrassonografia/métodos , Adulto , Doença Crônica , Sistemas Computacionais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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