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1.
Ultrasound Obstet Gynecol ; 48(2): 232-8, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26423450

RESUMO

OBJECTIVE: A prenatal ultrasound examination and a postmortem examination provide the basis for correct diagnosis in fetuses terminated due to congenital anomalies. The aim of this study was to correlate fetal anomalies detected by ultrasound examination with those identified at autopsy following termination of pregnancy (TOP) over a 30-year period, and to evaluate the correlation between findings at different gestational ages and assess these trends over time. METHODS: The study group consisted of 1029 TOPs performed over a 30-year period, from 1985 to 2014. The gestational age ranged between 11 and 33 weeks. Prenatal ultrasound examinations were performed at the National Center for Fetal Medicine, St Olavs Hospital, Trondheim, Norway. Autopsies were performed at the Department of Pathology and Medical Genetics at the same hospital or a collaborating hospital. RESULTS: There was full agreement between ultrasound and autopsy findings in 88.1% (907/1029) of TOPs, and the main diagnosis was correct in 97.9% (1007/1029). When comparing the 15-year period of 2000-2014 with that of 1985-1999, the difference in the rates of full agreement and agreement in the main diagnosis was statistically significant. In 1.3% (13/1029) of cases, ultrasound findings were not confirmed at autopsy. There were no false-positive diagnoses leading to TOP. Throughout the 30-year period, there was an increase in early TOPs, whereas late TOPs declined. CONCLUSIONS: Our study demonstrates that there is a clear correlation between ultrasound and autopsy findings, which is continuously improving. Despite this high correlation, there is reason to continue the practice of validation to ensure the safety of the diagnostic process leading to TOP. The trend towards an earlier termination emphasizes the necessity of such a practice. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Anormalidades Múltiplas/patologia , Aborto Eugênico/tendências , Ultrassonografia Pré-Natal/métodos , Anormalidades Múltiplas/diagnóstico por imagem , Anormalidades Múltiplas/epidemiologia , Aborto Eugênico/estatística & dados numéricos , Adolescente , Adulto , Autopsia , Feminino , Idade Gestacional , Humanos , Idade Materna , Noruega/epidemiologia , Gravidez , Sensibilidade e Especificidade , Ultrassonografia Pré-Natal/estatística & dados numéricos , Adulto Jovem
2.
Ultrasound Obstet Gynecol ; 40(2): 230-4, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22374812

RESUMO

Autopsies of fetuses with thanatophoric dysplasia (TD) have shown abnormal gyration of the temporal lobes. In addition, the head is relatively large compared with the abdomen. We evaluated by ultrasound six consecutive cases of TD at 19 + 0 to 19 + 6 gestational weeks based on last menstrual period. We observed abnormal and deep transverse sulci in the temporal lobes in all cases; these features were confirmed at autopsy. We performed biometric assessment, including biparietal diameter (BPD) and mean abdominal diameter (MAD). For each MAD value in the TD fetuses, we computed mean and SD of the corresponding BPD values from a population-based registry in the relevant age range, and used them to calculate Z-scores for each BPD/MAD ratio. In the general population, the average BPD/MAD ratio was 1.05. In the TD fetuses, the mean BPD was 51.5 (range, 49-54) mm, the MAD was 45 (range, 41-47) mm and the BPD/MAD ratio was 1.15 (range, 1.09-1.20). The average Z-score of the ratios for TD fetuses was 2.44 (range, 1.05-3.39). The ratios for the TD fetuses were significantly higher than were the population ratios (P = 0.016). At autopsy, the mean brain-to-body weight ratio was 20.6% (range, 15.4-24.1%), which was greater than the corresponding mean ratio of 14.9% in normal fetuses. We conclude that abnormal and deep transverse gyration of the temporal lobes can be visualized by ultrasound in mid-second-trimester fetuses with TD. Due to megalencephaly, fetuses with TD have significantly different body proportions, with a larger BPD compared with normal fetuses.


Assuntos
Megalencefalia/diagnóstico por imagem , Lobo Temporal/anormalidades , Lobo Temporal/diagnóstico por imagem , Displasia Tanatofórica/diagnóstico por imagem , Ultrassonografia Pré-Natal/métodos , Biometria , Feminino , Humanos , Gravidez
3.
Ultrasound Obstet Gynecol ; 39(6): 666-72, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21953982

RESUMO

OBJECTIVE: To determine if postmortem examinations of fetuses and infants change the diagnosis obtained at prenatal ultrasound and affect counseling of future pregnancies, and if there has been a change over recent years in the accuracy of prenatal ultrasound diagnosis. METHODS: This was a retrospective review of 455 autopsies of fetuses and infants with developmental anomalies performed at Trondheim University Hospital between 1995 and 2004 and with a prenatal ultrasound examination performed at a tertiary referral center. The routine ultrasound examinations were performed by specially trained midwives and obstetricians, referral scans by fetal medicine experts and autopsies by consultant pathologists with experience in perinatal pathology. The results of this study were also compared with those of a previous similar study performed between 1985 and 1995, with fetuses and infants coming from the same population and diagnosed at the same center. RESULTS: Of all cases analyzed during the study period, there was complete agreement between prenatal ultrasound and postmortem findings in 84% (384/455), i.e. prenatal ultrasound diagnoses were supplemented by postmortem examinations in 16% (71/455). Autopsy findings in four of these cases influenced further counseling. There was agreement regarding the main diagnosis in 98% (445/455) of cases. In the previous 10-year period, there was complete agreement in 75% and the main diagnosis was correct in 90% of cases. These differences between the two time periods were statistically significant (P = 0.0004 and P < 0.0001, respectively). The most frequent defects involved the central nervous system, heart and urinary tract. For these defects, detection rates for the main diagnoses were significantly better in 1995-2004 compared with in the previous 10-year period (P = 0.0125, P = 0.0111 and P = 0.0241, respectively). CONCLUSION: The accuracy of prenatal sonographic detection of developmental anomalies has increased in recent years. However, postmortem examination is still necessary to verify or improve the prenatal diagnosis and may influence future counseling.


Assuntos
Autopsia , Anormalidades Congênitas/diagnóstico , Morte Fetal , Doenças Fetais/diagnóstico , Feto/anormalidades , Ultrassonografia Pré-Natal , Adulto , Anormalidades Congênitas/diagnóstico por imagem , Anormalidades Congênitas/mortalidade , Feminino , Doenças Fetais/diagnóstico por imagem , Doenças Fetais/mortalidade , Feto/patologia , Humanos , Recém-Nascido , Consentimento Livre e Esclarecido , Noruega , Gravidez , Reprodutibilidade dos Testes , Estudos Retrospectivos
4.
Z Gastroenterol ; 49(6): 740-8, 2011 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-21638241

RESUMO

Surgery has been the mainstay of therapy in patients with gastrointestinal perforations, leakage or fistulas. New techniques for endoscopic closure of gastrointestinal perforations provide tools for an effective treatment by less invasive procedures. Temporary placement of covered self-expanding stents is an established therapy for oesophageal perforations and anastomotic leaks. Using conventional endoclips small perforations and leaks in the oesophagus and gastrointestinal tract may be closed. With the new over-the-scope-clips a more effective endoscopic full wall closure is possible in the upper gastrointestinal tract and the rectum. Endoscopically guided endoluminal vacuum therapy using polyurethane sponges is an established method for treating rectal leaks and is now increasingly used also in oesophageal leaks. Biliary leakage following endoscopic or surgical interventions is effectively treated with temporary bile stenting in most cases, but closure using metal stents or coiling may be necessary. Pancreatic leaks are a major therapeutic problem and may require multimodal therapies.


Assuntos
Doenças dos Ductos Biliares/cirurgia , Endoscopia do Sistema Digestório/métodos , Endoscopia do Sistema Digestório/tendências , Gastroenteropatias/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Procedimentos Cirúrgicos Minimamente Invasivos/tendências , Pancreatopatias/cirurgia , Doenças dos Ductos Biliares/patologia , Gastroenteropatias/patologia , Humanos , Pancreatopatias/patologia
5.
J Appl Microbiol ; 109(6): 1937-45, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21070515

RESUMO

AIMS: This study intended to unravel the physiological interplay in an anaerobic microbial community that degrades toluene under sulfate-reducing conditions combining proteomic and genetic techniques. METHODS AND RESULTS: An enriched toluene-degrading community (Zz5-7) growing in batch cultures was investigated by DNA- and protein-based analyses. The affiliation and diversity of the community were analysed using 16S ribosomal RNA (rRNA) genes as a phylogenetic marker as well as bssA and dsrAB genes as functional markers. Metaproteome analysis was carried out by a global protein extraction and a subsequent protein separation by two-dimensional gel electrophoresis (2-DE). About 85% of the proteins in the spots were identified by nano-liquid chromatography coupled with electrospray mass spectrometry (nano-LC-ESI-MS/MS) analysis. DNA sequencing of bssA and the most abundant dsrAB amplicons revealed high similarities to a member of the Desulfobulbaceae, which was also predominant according to 16S rRNA gene amplicons. Metaproteome analysis provided 202 unambiguous protein identifications derived from 236 unique protein spots. The proteins involved in anaerobic toluene activation, dissimilatory sulfate reduction, hydrogen production/consumption and autotrophic carbon fixation were mainly affiliated to members of the Desulfobulbaceae and several other Deltaproteobacteria. CONCLUSION: Phylogenetic and metaproteomic analyses revealed a member of the Desulfobulbaceae as the key player of anaerobic toluene degradation in a sulfate-reducing consortium. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first study that combines genetic and proteomic analyses to indicate the interactions in an anaerobic toluene-degrading microbial consortium.


Assuntos
Consórcios Microbianos , Filogenia , Proteoma/metabolismo , Tolueno/metabolismo , Biodegradação Ambiental , Cromatografia Líquida , DNA Bacteriano/genética , Deltaproteobacteria/genética , Deltaproteobacteria/metabolismo , Eletroforese em Gel Bidimensional , Polimorfismo de Fragmento de Restrição , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Espectrometria de Massas em Tandem
6.
Sci Total Environ ; 708: 135152, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31812384

RESUMO

Natural attenuation represents all processes that govern contaminant mass removal, which mainly occurs via microbial degradation in the environment. Although this process is intrinsic its rate and efficiency depend on multiple factors. This study aimed to characterize the microbial taxonomic and functional diversity in different aquifer sediments collected in the saturated zone and in situ microcosms (BACTRAP®s) amended with hydrocarbons (13C-labeled and non-labeled benzene, toluene and naphthalene) using 16S rRNA gene and "shotgun" Illumina high throughput sequencing at a jet-fuel contaminated site. The BACTRAP®s were installed to assess hydrocarbon metabolism by native bacteria. Results indicated that Proteobacteria, Actinobacteria and Firmicutes were the most dominant phyla (~98%) in the aquifer sediment samples. Meanwhile, in the benzene- and toluene-amended BACTRAP®s the phyla Firmicutes and Proteobacteria accounted for about 90% of total community. In the naphthalene-amended BACTRAP®, members of the SR-FBR-L83 family (Order Ignavibacteriales) accounted for almost 80% of bacterial community. Functional annotation of metagenomes showed that only the sediment sample located at the source zone border and with the lowest BTEX concentration, has metabolic potential to degrade hydrocarbons aerobically. On the other hand, in situ BACTRAP®s allowed enrichment of hydrocarbon-degrading bacteria. Metagenomic data suggest that fumarate addition is the main mechanism for hydrocarbon activation of toluene. Also, indications for methylation, hydroxylation and carboxylation as activation mechanisms for benzene anaerobic conversion were found. After 120 days of exposure in the contaminated groundwater, the isotopic analysis of fatty acids extracted from BACTRAP®s demonstrated the assimilation of isotopic labeled compounds in the cells of microbes expressed by strong isotopic enrichment. We propose that the microbiota in this jet-fuel contaminated site has metabolic potential to degrade benzene and toluene by a syntrophic process, between members of the families Geobacteraceae and Peptococcaceae (genus Pelotomaculum), coupled to nitrate, iron and/or sulfate reduction.


Assuntos
Metagenoma , Microbiota , Biodegradação Ambiental , Hidrocarbonetos , RNA Ribossômico 16S
7.
Science ; 264(5159): 692-6, 1994 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-17737955

RESUMO

Oxygen isotope records of cores from the central Arctic Ocean yield evidence for a major influx of meltwater at the beginning of the last deglaciation 15.7 thousand years ago (16,650 calendar years B.C.). The almost parallel trends of the isotope records from the Arctic Ocean, the Fram Strait, and the east Greenland continental margin suggest contemporaneous variations of the Eurasian Arctic and Greenland (Laurentide) ice sheets or increased export of low-saline waters from the Arctic within the East Greenland Current during the last deglaciation. On the basis of isotope and carbon data, the modern surface- and deep-water characteristics and seasonally open-ice conditions with increased surface-water productivity were established in the central Arctic at the end of Termination lb about 7.2 thousand years ago or 6,000 calendar years B.C.).

9.
Ultraschall Med ; 30(6): 544-50, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19998208

RESUMO

PURPOSE: The aim of the study was to characterize SonoVue enhancement in hepatocellular carcinoma in correlation to both lesion diameter and histological differentiation of the lesion. MATERIALS AND METHODS: In a prospective study 130 patients (72 male, 58 female, 62 +/- 10 years) with HCC lesions detected by B-mode sonography were examined. After injection of 1.2 - 2.4 ml SonoVue, HCC lesions were examined continuously for up to 5 min using "low MI" sonography. RESULTS: Arterial hypervascularization was found in 72 % of the HCC lesions without correlation to the lesion diameter or histological grading, when analyzed for the total group. However, the analysis of the G 1 subgroup showed significant correlation between lesion diameter and arterial hypervascularization. Arterial hypervascularization was found in 95 % of the G 1 lesions > 3 cm but in only 43 % of the G 1 lesions < 3 cm (p < 0.001). In contrast, analysis of the remaining HCC lesions (without G 1) showed arterial hypervascularization in 69 % of the lesions < 3 cm and in 72 % of the lesions > 3 cm (n. s.) without correlation to the diameter. In the late phase in the G 1 subgroup, hypoechoic demarcation was found in 95 % of the G 1 lesions > 3 cm, but in only 64 % of the G 1 lesions < 3 cm (p < 0.001). In contrast, in the less differentiated HCC lesions (without G 1), hypoechoic demarcation was found in 91 % (HCC > 3 cm) and in 82 % (HCC < 3 cm) of the lesions (n. s.). CONCLUSION: In well-differentiated HCCs (G1) hyperechoic enhancement in the arterial phase and hypoechoic demarcation in the late phase correlate to the diameter.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Fosfolipídeos , Hexafluoreto de Enxofre , Idoso , Carcinoma Hepatocelular/patologia , Diferenciação Celular , Meios de Contraste , Diagnóstico Diferencial , Feminino , Humanos , Aumento da Imagem , Fígado/diagnóstico por imagem , Fígado/patologia , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade , Ultrassonografia
10.
Acta Biomater ; 98: 186-195, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31352109

RESUMO

Volume stable barrier membranes made of magnesium are very promising in Guided Bone Regeneration (GBR) to treat periodontal bone defects in dentistry due to their excellent biocompatibility and biodegradability. During the degradation process the cells are exposed to the alteration of various parameters, so called physical cues, involving surface alterations due to the formed corrosion layer and medium alterations arising from the dissolved corrosion products. Cell migration of human gingival fibroblasts (HGF), as a crucial parameter for optimal healing process in GBR, has been investigated on magnesium membranes and revealed that medium alterations by dissolved corrosion products have a higher impact on cell migration than surface alterations. However, the effect of each altered medium parameter on cell migration has not been adequately studied, but their roles are crucial to explain the slower migration rate on magnesium surfaces compared to titanium and tissue culture plastic surfaces. Our study investigates the single effect of Mg2+, Ca2+, H2 and increased osmolality as well as the effect of magnesium extracts, which contain a dynamic mixture of previous parameters on cell migration, proliferation and viability of HGF. We showed that at 75 mM Mg2+ concentration and at 0 mM Ca2+, respectively, the cell migration rate is greatly reduced. In complex magnesium extract media, we found that a temporarily increased ratio of Mg2+ to Ca2+ conditioned a slow HGF migration rate. Based on these findings and the characterization of supernatants from HGF migration assays on Mg membranes, we propose, that the slower migration rate of HGF can be explained by the altered ratio of Mg2+ to Ca2+, caused by increasing concentrations of Mg2+ and decreasing concentrations of Ca2+ in the vicinity of the corroding Mg implant, combined with a constantly increased molecular hydrogen concentration in the supernatant. These results are cell type specific and should be checked carefully, if necessary, for Mg implant performance. STATEMENT OF SIGNIFICANCE: The study is providing a systematic approach to explain the main effects of extract medium parameters (physical cues) such as magnesium or calcium ion concentration, osmolality and dissolved molecular hydrogen and CO2 in cell culture media modified by co-incubating with corroding magnesium implants on the migration rate of human gingival fibroblasts (HGF). This study uncovers for the first time the combinatory effect of slightly increased molecular hydrogen and the change in Mg2+/Ca2+ ratio on HGF cell migration.


Assuntos
Implantes Absorvíveis , Fibroblastos/citologia , Gengiva/citologia , Magnésio/farmacologia , Cálcio/farmacologia , Movimento Celular/efeitos dos fármacos , Corrosão , Meios de Cultura , Fibroblastos/efeitos dos fármacos , Humanos , Hidrogênio/farmacologia , Íons
11.
Br J Pharmacol ; 153(5): 886-93, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17891166

RESUMO

BACKGROUND AND PURPOSE: Diabetes-associated vascular dysfunction contributes to increased cardiovascular risk. We investigated whether the phosphodiesterase-5 inhibitor sildenafil would improve vascular function in diabetic rats. EXPERIMENTAL APPROACH: Male Wistar rats were injected with streptozotocin (50 mg kg(-1), i.v.) to induce insulin-deficient diabetes. Direct effects of sildenafil as well as modification of endothelium-dependent and -independent vasorelaxation were investigated in vitro. The effects of acute and chronic (2 week) treatment in vivo of sildenafil on vascular function were also characterized in isolated aortic segments in organ bath chambers 4 weeks after diabetes induction. KEY RESULTS: Sildenafil induced a concentration-dependent vasorelaxation, which was attenuated by the nitric oxide (NO) synthase inhibitor, N(G)-nitro-L-arginine. Acetylcholine-induced endothelium-dependent as well as endothelium-independent relaxation induced by the NO donor, DEA-NONOate, was significantly reduced in aortae from diabetic rats. Incubation with sildenafil in vitro normalized both endothelium-dependent and -independent relaxation in aortae from diabetic rats. Acute as well as chronic in vivo treatment with sildenafil resulted in enhanced endothelium-dependent and -independent vasorelaxation. Superoxide formation was increased in diabetes, associated with enhanced membrane expression of the NAD(P)H oxidase subunit gp91(phox) and Rac, which were both reduced by chronic treatment with sildenafil. CONCLUSIONS AND IMPLICATIONS: We demonstrate that sildenafil treatment rapidly and chronically improves vascular relaxation in diabetic rats. Treatment with sildenafil might provide a similarly beneficial effect in diabetic patients.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Inibidores de Fosfodiesterase/farmacologia , Piperazinas/farmacologia , Sulfonas/farmacologia , Vasodilatação/efeitos dos fármacos , Acetilcolina/farmacologia , Animais , Aorta Torácica/metabolismo , Diabetes Mellitus Experimental/fisiopatologia , Relação Dose-Resposta a Droga , Esquema de Medicação , Endotélio Vascular/efeitos dos fármacos , Masculino , Óxido Nítrico Sintase/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Inibidores de Fosfodiesterase/administração & dosagem , Piperazinas/administração & dosagem , Purinas/administração & dosagem , Purinas/farmacologia , Ratos , Ratos Wistar , Citrato de Sildenafila , Estreptozocina , Sulfonas/administração & dosagem , Superóxidos/metabolismo
13.
Eur J Med Res ; 11(1): 13-9, 2006 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-16504955

RESUMO

PURPOSE: To assess the most favorable slice thickness in Multi-Detector-Row CT-colonography (MDCTC), and the feasibility of dose reduction in an in-vitro-setting as well as the possibility of optimization of image quality using a noise reduction filter algorithm. - MATERIALS AND METHODS: 18 artificial lesions with sizes from 1 to 8 mm were randomly positioned in two cleansed pig colons. At a "Somatom Plus 4 Volume Zoom", six scanning protocols using a slice collimation of 2.5, 1, and 1 mm with a reconstructed slice thickness of 3, 3, and 1.25 mm were performed with tube currents of 100, and 10 mAs, respectively. Using a non-commercial software, a non-linear Gaussian filter was used to minimize image noise. Image noise was assessed before and after application of the filtering process. Using a threshold of -750 HU, two blinded readers analyzed the virtual colonography in respect to lesion location, size, and shape. Artifacts were noted. An automated detection system was evaluated. - RESULTS: Using 10 mAs, a ten-fold dose reduction was achieved. After application of the mathematical filter, image noise was reduced by 45-80% for 100 mAs, and by 50-70% for 10 mAs scans. Only with a slice thickness of 1.25 mm, all lesions could be detected. The definition of lesion size and shape was more accurate with higher mAs. Only minor noise artifacts were noted on low-dose images. The automated polyp detector marked not more than 60% of artificial lesions. - CONCLUSION: MDCTC benefits from narrow slice collimation. In an in-vitro-model, a significant dose reduction is achievable with preservation of a high lesion detection rate. The noise reduction filter algorithm improved image quality substantially.


Assuntos
Algoritmos , Pólipos do Colo/diagnóstico por imagem , Colonografia Tomográfica Computadorizada/métodos , Animais , Pólipos do Colo/patologia , Humanos , Modelos Animais , Imagens de Fantasmas , Suínos
14.
Acta Biomater ; 44: 355-65, 2016 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-27497845

RESUMO

UNLABELLED: Magnesium as basic implant material has long been the center of orthopedic research. Latest progress is achieved with a European certification and clinical use of a magnesium based compression screw. However, long term studies with implantation duration that exceed one year considerably do not exist. The present examinations analyzed the degradation progress from nine months to 3.5year after implantation of cylindrical pins into the medullary cavity of New Zealand White rabbits. Evaluation included clinical assessment, in vivo µ-computed tomography, analysis of the implants by three-point-bending and examination of the adjacent tissue by means of histology and of inner organs by mass- and optical emission spectrometry using inductively coupled plasma. Clinical acceptance was without objections in all animals. Immoderate reaction of the surrounding bone could be found in neither of the applied techniques. While in vivo µ-computed tomography showed a very slow degradation rate up to 72weeks, three-point-bending revealed a percentage loss of F(max) of 41.1% for implants after 9months implantation and 88.47% for the implant after 3.5years implantation. Although the total amounts of RE detected in the inner organs were very low, the organs of rabbits with LAE442 cylinders showed 10-20-fold increased concentrations of the alloying elements lanthanum, cerium, neodymium and praseodymium compared to animals without any implanted material. STATEMENT OF SIGNIFICANCE: This is the first animal study investigating the degradation process of a magnesium alloy in vivo for up to 3.5years. Currently available data from different other in vivo studies cover only implantation durations up to one year. Therefore, the analysis of these long-time effects in the present study is highly significant and of great interest. Comprehensive outcome achieved by different techniques was assessed. The degradation process was slow and homogenous. Maximum applied force (F(max)) reduced by 41.1% for implants after 9months and by 88.47% for the implant after 3.5years implantation. Total amounts of RE detected in the inner organs were very low; the organs of rabbits with LAE442 cylinders showed 10-20-fold increased concentrations.


Assuntos
Ligas/farmacologia , Materiais Biocompatíveis/farmacologia , Implantes Experimentais , Magnésio/farmacologia , Animais , Corrosão , Modelos Animais de Doenças , Feminino , Teste de Materiais , Coelhos , Espectrometria por Raios X , Tíbia/fisiologia , Microtomografia por Raio-X
15.
Biochim Biophys Acta ; 393(1): 78-87, 1975 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-1138926

RESUMO

Glomeruli were isolated from rat renal cortex and incubated with radioactive lysine to study in vitro collagen synthesis in these preparations. Glomerular basement membrane was obtained by sonication, and the appearance of [-14C]lysine and hydroxylysine in medium, membrane and intracellular proteins was determined. Total glomerular incorporation of [-14C]lysine into protein linearly increased for up to 2-h period, and membrane hydroxylysine content gradually rose during this time. Hydroxy[-14C]lysine was recovered in the 105 000 times g pellet, reaching a hydroxylysine content of 22 percent in this intracellular fraction after 90 min of incubation. 60 percent of the protein secreted into the medium, and about 75 percent of newly synthesized sonicated basement membrane was acetic acid soluble. Hydroxylysine content was 33 percent in the acetic acid-insoluble fraction of sonicated membrane, suggesting that basement-membrane collagen was a significant component of total collagen synthesized by these preparation, The ability of isolated glomeruli to synthesize and secrete basement-membrane protein will be useful for studies concerning control of glomerular collagen and basement-membrane synthesis.


Assuntos
Colágeno/metabolismo , Glomérulos Renais/metabolismo , Animais , Membrana Celular/metabolismo , Colágeno/biossíntese , Hidroxilisina/metabolismo , Cinética , Lisina/metabolismo , Ratos , Solubilidade , Sonicação , Fatores de Tempo
16.
Diabetes ; 47(3): 387-94, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9519744

RESUMO

NIDDM and obesity are characterized by decreased insulin-stimulated glucose uptake in muscle. It has been suggested that impaired glucose phosphorylation to glucose-6-phosphate, catalyzed in muscle by hexokinase (HK)II, may contribute to this insulin resistance. Insulin is known to increase HKII mRNA, protein, and activity in lean nondiabetic individuals. The purpose of this study was to determine whether defects in insulin-stimulated HKII expression and activity could contribute to the insulin resistance of obesity and NIDDM. Fifteen lean nondiabetic control subjects, 17 obese nondiabetic subjects, and 14 obese NIDDM patients were studied. Percutaneous muscle biopsies of the vastus lateralis were performed in conjunction with leg balance and local indirect calorimetry measurements before and at the end of a 3-h euglycemic-hyperinsulinemic clamp (40 or 240 mU x min(-1) x m[-2]). Leg glucose uptake in response to the 40-mU insulin infusion was higher in the lean control subjects (2.53 +/- 0.35 micromol x min(-1) per x 100 ml leg vol) than in obese (1.46 +/- 0.50) or NIDDM (0.53 +/- 0.25, P < 0.05) patients. In response to 240 mU insulin, leg glucose uptake was similar in all of the groups. In response to 40 mU insulin, HKII mRNA in lean control subjects was increased 1.48 +/- 0.18-fold (P < 0.05) but failed to increase significantly in the obese (1.12 +/- 0.24) or NIDDM (1.14 +/- 0.18) groups. In response to 240 mU insulin, HKII mRNA was increased in all groups (control subjects 1.48 +/- 0.18, P < 0.05 vs. basal, obese 1.30 +/- 0.16, P < 0.05, and NIDDM 1.25 +/- 0.14, P < 0.05). Under basal conditions, HKI and HKII activities did not differ significantly between groups. Neither the 40 mU nor the 240 mU insulin infusion affected HK activity. Total HKII activity was reduced in the obese subjects (4.33 +/- 0.08 pmol x min(-1) x g(-1) muscle protein) relative to the lean control subjects (5.00 +/- 0.08, P < 0.05). There was a further reduction in the diabetic patients (3.10 +/- 0.10, P < 0.01 vs. the control subjects, P < 0.01 vs. the obese subjects). Resistance to insulin's metabolic effects extends to its ability to induce HKII expression in obesity and NIDDM.


Assuntos
Diabetes Mellitus Tipo 2/enzimologia , Regulação Enzimológica da Expressão Gênica/genética , Hexoquinase/genética , Hexoquinase/metabolismo , Obesidade/enzimologia , Adulto , Biópsia , Estudos de Coortes , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/fisiopatologia , Relação Dose-Resposta a Droga , Feminino , Glucose/metabolismo , Técnica Clamp de Glucose , Glicogênio Sintase/metabolismo , Hexoquinase/classificação , Humanos , Infusões Intravenosas , Insulina , Perna (Membro)/irrigação sanguínea , Perna (Membro)/fisiologia , Masculino , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Obesidade/metabolismo , Obesidade/fisiopatologia , RNA Mensageiro/análise , RNA Mensageiro/genética , Fluxo Sanguíneo Regional/fisiologia
17.
J Mol Biol ; 180(1): 111-29, 1984 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-6096557

RESUMO

Microinjection of early simian virus 40 (SV40) DNA fragments has shown that maximal transformation of rat cells (Ref 52) is a property of the second SV40 T-antigen exon. Expression of this particular T-antigen region was obtained by coinjection of the Taq/Bam DNA fragment with the early promoter/enhancer HpaII/BglI fragment. Microinjection of the DNA fragment mixture induced two categories of transformants; namely, maximally and minimally transformed cells. The maximally transformed cells synthesize two Taq/Bam-specific polypeptides, and the minimally transformed cells only the lower molecular weight form. Both types of transformants contain the cellular p52 protein at high concentrations. Furthermore, maximal transformation of Ref 52 cells requires the carboxy terminus of the T-antigen. Cells transformed by microinjection of the SV40 Pst A-fragment display different parameters of maximally transformed cells but not anchorage-independent growth.


Assuntos
Antígenos Virais de Tumores/genética , Transformação Celular Viral , DNA Viral , Genes Virais , Vírus 40 dos Símios/genética , Animais , Antígenos Virais de Tumores/análise , Sequência de Bases , Linhagem Celular , Transformação Celular Neoplásica , Eletroforese em Gel de Ágar , Eletroforese em Gel de Poliacrilamida , Camundongos , Hibridização de Ácido Nucleico , RNA Viral , Vírus 40 dos Símios/imunologia
18.
Rofo ; 177(9): 1227-34, 2005 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-16123868

RESUMO

PURPOSE: To compare a commercial CT colonography software ("Colonography", Siemens, Forchheim) with a non-commercial post-processing system ("Colotux", Department of Informatics). MATERIAL AND METHODS: Identical data sets of 10 patients, who underwent an ultra-low-dose multi-detector CT colonography (ULD-MDCTC) (4x1 mm collimation, 8 mm pitch, 120 kVp, 10 mAs) were analyzed retrospectively. Assessment was performed using both software solutions by two resident radiologists, who did not have any experience with any colonography software tool before and who did not know the clinical symptoms of the patients or the results of the conventional colonoscopy. Both systems were analyzed using several subjective quality criteria including workflow, handling, image quality, endoluminal navigation and analysis of lesions with grading on a 5-point-scale. Results concerning polyps were compared between the two systems as well as with conventional colonoscopy. RESULTS: Both colonography systems detected the same number of polyps. Although both showed some advantages for single criteria, no relevant difference was noted in general for subjective assessment. The time for calculation of three dimensional interactive volumes was three times longer for "Colotux" compared to "Colonography." Linux-based "Colotux" showed a trend towards better subjective image quality and easier measurement of polyp size. An intuitive desktop and "Syngo"-workflow integration were advantages of "Colonography." CONCLUSION: The analysis of CT colonographies (4-detector-row-CT-scanner, ultra low dose technique, supine position) can adequately be achieved by both software solutions. There was no significant subjective or objective difference of quality between a "stand-alone" individual system and a commercial workflow-integrated solution. A relevant factor for decision between the two systems may be the difference in time needed for the 3D volume calculation, especially in institutes with a high frequency of examinations.


Assuntos
Colonografia Tomográfica Computadorizada , Software , Idoso , Pólipos do Colo/diagnóstico por imagem , Colonografia Tomográfica Computadorizada/instrumentação , Colonografia Tomográfica Computadorizada/métodos , Colonoscopia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
19.
Exp Hematol ; 17(5): 391-7, 1989 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2714418

RESUMO

Macrophages derived from unstimulated and unseparated mouse bone marrow cells cultivated on hydrophobic foils can release hemopoietic regulator molecules into the surrounding medium. To prove that one of these regulators exists in macrophages in vitro, in situ hybridization using a 1.2-kb erythropoietin (Epo) gene probe was employed. The probe was biotinylated and the signal developed using a streptavidin-gold reagent. Observation was performed using reflection-contrast microscopy. The results indicate that from a 98% pure population of macrophages, 34% F4/80 (mouse, macrophage-specific antigenic determinant)-positive macrophages exhibited Epo gene expression. The technique was also applied to normal, steady-state mouse bone marrow in which approximately 10% of the cells are F4/80-positive and of which about 3% demonstrated simultaneous Epo gene expression. As positive control, kidneys from anemic mice were hybridized with the biotin-labeled Epo DNA. A second positive control utilized biotin-labeled actin DNA hybridized to cultured macrophages and normal bone marrow cells. The accumulating information, demonstrating that the unstimulated kidney does not express the Epo gene, indicates that Epo is produced in other areas of the body under normal, steady-state conditions. The present results show that 1) macrophages can express the Epo gene, 2) this function is carried out by a subpopulation of macrophages, and 3) bone marrow macrophages in vivo may be responsible for the Epo production-target cell mechanism evoked by short-range and/or cell-to-cell interactions under normal, steady-state conditions.


Assuntos
Eritropoetina/genética , Regulação da Expressão Gênica , Macrófagos/fisiologia , Actinas , Animais , Células Cultivadas , Sondas de DNA , Eritropoetina/biossíntese , Feminino , Hematopoese , Immunoblotting , Camundongos , Camundongos Endogâmicos C57BL , Hibridização de Ácido Nucleico
20.
Endocrinology ; 110(5): 1641-6, 1982 May.
Artigo em Inglês | MEDLINE | ID: mdl-7075533

RESUMO

The 24-h pattern of plasma cortisol and changes induced by alterations of the sleep/wake cycle were studied in 12 male rhesus monkeys. The chair-living animals were chronically prepared with a right atrial catheter and electroencephalogram electrodes. Hormone (blood samples every 15 min) and continuous activity/electroencephalogram profiles were obtained from the adjacent room for 96 h (4 animals), 24 h or various shorter periods of time. Plasma cortisol showed a circadian rhythm with a late evening minimum (1900-2100 h; approximately 60 micrograms/liter) and an early morning maximum (0400-0700 h; approximately 160 micrograms/liter). Superimposed were episodic fluctuations for which powerspectral analysis showed a weakly expressed 30- to 60-min periodicity in 24 of 27 24-h profiles. Cross-correlation analysis indicated no relation between cortisol on the one hand and daytime activity-arousal, nocturnal waking, slow wave sleep (SWS) or rapid eye movement sleep (REM), respectively. Five-hour total sleep deprivation, specific SWS-deprivation, and severe disruption of the REM-pattern provided no evidence for an immediate effect of sleep onset or sleep stages on the cortisol pattern. Cortisol rose significantly after termination of the 5-h deprivation, but the mechanism of this elevation remains to be determined. Cross-correlation analysis between the cortisol time series and those of GH, PRL, and TSH from already published data gave no evidence for a regular temporal relationship between the episodic patterns of these hormones.


Assuntos
Ritmo Circadiano , Hidrocortisona/sangue , Sono/fisiologia , Vigília/fisiologia , Animais , Hormônio do Crescimento/sangue , Macaca mulatta , Prolactina/sangue , Tireotropina/sangue
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