Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 78
Filtrar
1.
Arch Gynecol Obstet ; 309(4): 1353-1367, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36971845

RESUMO

OBJECTIVE: Restrictive foramen ovale (FO) in dextro-transposition of the great arteries (d-TGA) with intact ventricular septum may lead to severe life-threatening hypoxia within the first hours of life, making urgent balloon atrial septostomy (BAS) inevitable. Reliable prenatal prediction of restrictive FO is crucial in these cases. However, current prenatal echocardiographic markers show low predictive value, and prenatal prediction often fails with fatal consequences for a subset of newborns. In this study, we described our experience and aimed to identify reliable predictive markers for BAS. METHODS: We included 45 fetuses with isolated d-TGA that were diagnosed and delivered between 2010 and 2022 in two large German tertiary referral centers. Inclusion criteria were the availability of former prenatal ultrasound reports, of stored echocardiographic videos and still images, which had to be obtained within the last 14 days prior to delivery and that were of sufficient quality for retrospective re-analysis. Cardiac parameters were retrospectively assessed and their predictive value was evaluated. RESULTS: Among the 45 included fetuses with d-TGA, 22 neonates had restrictive FO postnatally and required urgent BAS within the first 24 h of life. In contrast, 23 neonates had normal FO anatomy, but 4 of them unexpectedly showed inadequate interatrial mixing despite their normal FO anatomy, rapidly developed hypoxia and also required urgent BAS ('bad mixer'). Overall, 26 (58%) neonates required urgent BAS, whereas 19 (42%) achieved good O2 saturation and did not undergo urgent BAS. In the former prenatal ultrasound reports, restrictive FO with subsequent urgent BAS was correctly predicted in 11 of 22 cases (50% sensitivity), whereas a normal FO anatomy was correctly predicted in 19 of 23 cases (83% specificity). After current re-analysis of the stored videos and images, we identified three highly significant markers for restrictive FO: a FO diameter < 7 mm (p < 0.01), a fixed (p = 0.035) and a hypermobile (p = 0.014) FO flap. The maximum systolic flow velocities in the pulmonary veins were also significantly increased in restrictive FO (p = 0.021), but no cut-off value to reliably predict restrictive FO could be identified. If the above markers are applied, all 22 cases with restrictive FO and all 23 cases with normal FO anatomy could correctly be predicted (100% positive predictive value). Correct prediction of urgent BAS also succeeded in all 22 cases with restrictive FO (100% PPV), but naturally failed in 4 of the 23 cases with correctly predicted normal FO ('bad mixer') (82.6% negative predictive value). CONCLUSION: Precise assessment of FO size and FO flap motility allows a reliable prenatal prediction of both restrictive and normal FO anatomy postnatally. Prediction of likelihood of urgent BAS also succeeds reliably in all fetuses with restrictive FO, but identification of the small subset of fetuses that also requires urgent BAS despite their normal FO anatomy fails, because the ability of sufficient postnatal interatrial mixing cannot be predicted prenatally. Therefore, all fetuses with prenatally diagnosed d-TGA should always be delivered in a tertiary center with cardiac catheter stand-by, allowing BAS within the first 24 h after birth, regardless of their predicted FO anatomy.


Assuntos
Forame Oval , Transposição dos Grandes Vasos , Gravidez , Feminino , Recém-Nascido , Humanos , Forame Oval/diagnóstico por imagem , Forame Oval/cirurgia , Transposição dos Grandes Vasos/diagnóstico por imagem , Transposição dos Grandes Vasos/cirurgia , Estudos Retrospectivos , Ultrassonografia Pré-Natal/métodos , Feto , Artérias , Hipóxia
2.
Internist (Berl) ; 61(4): 375-387, 2020 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-32144476

RESUMO

Against the background of increasing antimicrobial resistance, antibiotic stewardship (ABS) is an important measure to counteract the spread of resistant pathogens and multidrug resistance. For Germany and Austria, a comprehensive S3 guideline is available, which was last updated in 2018. The control of antibiotic or anti-infective use in hospitals should be guided by specialized ABS teams. At the hospital level, ABS also includes a structured ongoing analysis of local antibiotic use and resistance data. Recommendations for locally adapted therapy regimens should be derived and implemented from this data analysis. ABS consists of regular ward rounds ("ABS visits"), during which members of the ABS team review the indication, dosage, route of administration and duration of antimicrobial therapy at the bedside. Here, the key challenge is to save antibiotics without compromising the individual patient. Digitalization and artificial intelligence offer new options for ABS, while the adaption of inpatient concepts to outpatient care is also important.


Assuntos
Antibacterianos/administração & dosagem , Gestão de Antimicrobianos , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/prevenção & controle , Farmacorresistência Bacteriana , Anti-Infecciosos , Inteligência Artificial , Infecções Bacterianas/microbiologia , Prática Clínica Baseada em Evidências , Alemanha , Humanos , Guias de Prática Clínica como Assunto
3.
Internist (Berl) ; 61(5): 475-486, 2020 May.
Artigo em Alemão | MEDLINE | ID: mdl-32112153

RESUMO

Antibiotic stewardship (ABS) is an important measure to counteract the spread of resistant pathogens and multidrug resistance. The most important ABS tools include the implementation of local guidelines, the development of a house-related list of anti-infective agents, regular ABS visits and practice-oriented internal training events. Effective strategies for therapy optimization include indication testing and therapy evaluation, dose optimization as well as determining an appropriate duration of therapy. Oralization of anti-infectives (sequence therapy) should be supported by consistent clinical criteria in in-house guidelines. The incidence of Clostridioides difficile infections (CDI) can be more than halved by restricting the so-called "4C antibiotics". Point-of-care tests help to minimize the use of antibiotics in the outpatient setting. Vaccination reduces the need for antibiotic therapy.


Assuntos
Antibacterianos/administração & dosagem , Gestão de Antimicrobianos , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/prevenção & controle , Anti-Infecciosos/administração & dosagem , Infecções Bacterianas/microbiologia , Infecções por Clostridium/prevenção & controle , Surtos de Doenças/prevenção & controle , Farmacorresistência Bacteriana , Alemanha , Humanos
4.
Anim Cogn ; 22(3): 355-364, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30771027

RESUMO

Foraging animals use a variety of information sources to navigate, such as memorised views or odours associated with a goal. Animals frequently use different information sources concurrently, to increase navigation accuracy or reliability. While much research has focussed on conflicts between individually learned (private) information and social information, conflicts between private information sources have been less broadly studied. Here, we investigate such a conflict by pitting route memory against associative odour cue learning in the ant Lasius niger. Ants were alternatingly trained to find a high-quality scented food source on one arm of a Y-maze, and a differently scented low-quality food source on the opposite arm. After training, ants were presented with a Y-maze in which the high- and low-quality-associated scents were presented on opposite arms than during training. The ants showed an extremely strong preferential reliance on the odour cues, with 100% of ants following the high-quality odour and thus moving towards the side associated with low-quality food. Further experiments demonstrated that ants also learn odour associations more rapidly, requiring only one visit to each odour-quality combination to form a reliable association. Side associations in the absence of odours, by contrast, required at least two visits to each side for reliable learning. While much attention has been focussed on visual route learning in insect navigation and decision-making, our results highlight the overwhelming importance of odour cues in insect path choice.


Assuntos
Formigas , Sinais (Psicologia) , Memória , Olfato , Animais , Comportamento Animal , Condicionamento Clássico , Tomada de Decisões , Odorantes , Feromônios , Aprendizagem Espacial
5.
Faraday Discuss ; 208(0): 325-338, 2018 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-29877523

RESUMO

Low-coordinate surface sites, such as those present on high-index step edges, often exhibit chemical reactivity that markedly differs from more close-packed facets. To understand the site-specific reactivity, insight into the three-dimensional atomic arrangement of step edges is needed. Here, we employ atomic-resolution transmission electron microscopy (TEM) of nanoparticles in combination with scanning tunneling microscopy (STM) of a single crystal surface to uncover the structure of prevalent step edges on the anatase TiO2 (001) surface.

6.
Eur J Clin Microbiol Infect Dis ; 36(10): 1955-1964, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28560472

RESUMO

Coagulase-negative staphylococci (CoNS) are the most prevalent pathogens causing late-onset sepsis in neonates. The question is whether neonates acquire endemic hospital-adapted clones or incidentally occurring CoNS strains after birth during their hospital stay. Therefore, a prospective study was performed on the prevalence of CoNS in the stool of babies (born vaginally or by cesarean section) during their first days of life. Their clonal relatedness and potential to induce invasive disease were characterized. CoNS were analyzed from the stool samples of newborns with a load of CoNS above 103 colony-forming units (CFU)/mL. The identification of CoNS was performed phenotypically and genotypically. For typing, repetitive polymerase chain reaction (PCR), pulsed-field gel electrophoresis, and multilocus sequence typing were used. Resistance profiles, biofilm production, the presence of icaAD and of IS256 were determined as well. From a total of 207 stool samples (56 newborns), CoNS were detected in 41% of the newborns, mostly on day 3 for the first time (62.5%). Staphylococcus epidermidis was isolated in 85.7% of cases, harbored no IS256 element, and mostly expressed no biofilm. The isolates were separated into four main clusters by repetitive sequence-based PCR. 24% of the strains showed no antimicrobial resistance. 20% were resistant against four antibiotics of two different antibiotic classes. The remaining strains were resistant only against one antimicrobial substance class. Thus, it can be concluded that newborns do not acquire hospital-adapted endemic, multidrug-resistant S. epidermidis isolates during their first days of life. Yet, the results support the thesis that, during hospital stay, environmental parameters may convert sensible/noninvasive S. epidermidis strains into multidrug-resistant strains with characteristics of invasiveness.


Assuntos
Genótipo , Infecções Estafilocócicas/microbiologia , Staphylococcus epidermidis/classificação , Staphylococcus epidermidis/isolamento & purificação , Fatores de Virulência/análise , Carga Bacteriana , Técnicas de Tipagem Bacteriana , Fezes/microbiologia , Humanos , Recém-Nascido , Testes de Sensibilidade Microbiana , Tipagem Molecular , Prevalência , Estudos Prospectivos , Staphylococcus epidermidis/patogenicidade
7.
J Chem Phys ; 141(21): 214702, 2014 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-25481156

RESUMO

The nucleation and growth of Pt nanoparticles (NP's) on rutile TiO2 (110) surfaces with O on-top atoms (oxidized TiO2), surface O vacancies, and H adatoms, respectively (reduced TiO2), was studied by means of scanning tunneling microscopy (STM) experiments and density functional theory calculations. At room temperature, Pt was found to be trapped at O on-top atoms and surface O vacancies, leading to rather small Pt NP's. In contrast, on surfaces with H adatoms the mobility of Pt was much larger. As a result, large Pt NP's were found at room temperature on TiO2 (110) surfaces with H adatoms. However, at ∼150 K the diffusion of Pt was kinetically hindered on all TiO2 (110) surfaces considered. STM data acquired after vacuum-annealing at 800 K showed comparable results on all TiO2 (110) surfaces because the diffusion of Pt is not influenced by surface defects at such high temperatures.

8.
Phys Rev Lett ; 110(14): 146101, 2013 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-25167009

RESUMO

The water-TiO(2) interaction is of paramount importance for many processes occurring on TiO(2), and the rutile TiO(2)(110)-(1×1) surface has often been considered as a test case. Yet, no consensus has been reached whether the well-studied surface O vacancies on the terraces are the only active sites for water dissociation on rutile TiO(2)(110)-(1 × 1), or whether another channel for the creation of H adatoms exists. Here we use high-resolution scanning tunneling microscopy and density functional theory calculations to tackle this long-standing question. Evidence is presented that a second water dissociation channel exists on the surfaces of vacuum-annealed TiO(2)(110) crystals that is associated with the ⟨111⟩ step edges. This second water dissociation channel can be suppressed by blocking of the ⟨111⟩ step edges using ethanol.

9.
Inn Med (Heidelb) ; 64(5): 490-493, 2023 May.
Artigo em Alemão | MEDLINE | ID: mdl-36732426

RESUMO

Infestation with Enterobius vermicularis involving extraintestinal manifestation is rare. In a 50-year-old man with lower abdominal pain, computed tomography led to a suspected diagnosis of sigmoid carcinoma with liver metastasis. After ruling out colon cancer by endoscopy, laparoscopic resection of one suspected tumor nodule in the liver was performed. Histopathological examination revealed parasitic granulomas containing pinworms. Hematogenous migration was postulated in the setting of phlebitis with thrombosis of the inferior mesenteric vein.


Assuntos
Enterobíase , Neoplasias do Colo Sigmoide , Masculino , Animais , Humanos , Pessoa de Meia-Idade , Enterobius , Enterobíase/complicações , Dor Abdominal , Granuloma
10.
Phys Rev Lett ; 109(15): 155501, 2012 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-23102329

RESUMO

The rutile TiO2(110) surface is the most studied surface of titania and considered as a prototype of transition metal oxide surfaces. Reactions on flat TiO2(110)-(1×1) surfaces are well studied, but the processes occurring on the step edges have barely been considered. Based on scanning tunneling microscopy studies, we here present experimental evidence for the existence of O vacancies along the [11¯1](R) step edges (O(S) vac.'s) on rutile TiO(2)(110). Both the distribution of bridging O vacancies on the terraces and temperature-programed reaction experiments of ethanol-covered TiO(2)(110) point to the existence of the O(S) vac.'s. Based on experiments and density functional theory calculations, we show that O(S) vac.'s are reactive sites for ethanol dissociation via O-H bond scission. Implications of these findings are discussed.

11.
Phys Rev Lett ; 108(23): 236103, 2012 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-23003975

RESUMO

We have studied vicinal TiO2(110) surfaces by high-resolution scanning tunneling microscopy and density functional theory calculations. On TiO2 surfaces characterized by a high density of <111> steps, scanning tunneling microscopy reveals a high density of oxygen-deficient strandlike adstructures. With the help of density functional theory calculations we develop a complete structural model for the entire strand and demonstrate these adstructures to be more stable than an equivalent amount of bulk defects such as Ti interstitials. We argue that strands can form particularly easy on stepped surfaces because building material is available at step sites. The strands on TiO2(110) represent point defects that are densely packed into ordered adstructures.

12.
Phys Rev Lett ; 107(13): 136102, 2011 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-22026875

RESUMO

We have studied the interaction of ethanol with reduced TiO(2)(110)-(1 × 1) by high-resolution scanning tunneling microscopy (STM) measurements and density functional theory calculations. The STM data revealed direct evidence for the coexistence of molecularly and dissociatively adsorbed ethanol species on surface Ti sites. In addition, we found evidence for dissociation of ethanol at bridge-bonded O vacancies. The density functional theory calculations support these findings and rationalize the distinct diffusion behaviors of molecularly and dissociatively adsorbed ethanol species, as revealed in time-lapsed STM images.

13.
EJNMMI Res ; 11(1): 62, 2021 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-34216300

RESUMO

AIM: In 2015, the revised International Pediatric Non-Hodgkin Lymphoma Staging System was published. It mentions [18F]-FDG-PET/MRI as the latest method to perform whole-body imaging. However, supporting data are pending. Our aim was to investigate the performance of whole-body [18F]-FDG-PET/MRI in pediatric non-Hodgkin lymphoma patients by using a limited number of MRI sequences. MATERIALS AND METHODS: Ten pediatric patients with histologically proven non-Hodgkin lymphoma underwent whole-body [18F]-FDG-PET/MRI at staging. The retrospective analysis included three steps: First, [18F]-FDG-PET and MR scans were evaluated separately by a nuclear medicine physician and a pediatric radiologist. Nineteen nodal and two extranodal regions as well as six organs were checked for involvement. Second, discrepant findings were reviewed together in order to reach consensus. Third, [18F]-FDG-PET/MRI findings were correlated with the results of other clinical investigations. RESULTS: Of the 190 lymph node regions evaluated, four were rated controversial. Consensus was reached by considering metabolic, functional and morphologic information combined. Concordantly, [18F]-FDG-PET and MRI detected Waldeyer's ring involvement in two patients whose Waldeyer's ring was negative on clinical assessment. In four patients MRI showed pleural effusion. However, in only two of them an increased glucose metabolism as a reliable sign of pleural involvement was detectable. In six patients [18F]-FDG-PET and MRI detected skeletal lesions although bone marrow biopsy was positive in only one of them. CONCLUSION: Despite the small number of cases evaluated, whole-body [18F]-FDG-PET turned out to be a valuable tool for staging of pediatric non-Hodgkin lymphoma.

14.
Rehabilitation (Stuttg) ; 49(1): 38-47, 2010 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-20178060

RESUMO

Only 0.16% of disabled employees are enabled to change from sheltered workshops to the general labour market. At the same time the number of disabled employees in sheltered workshops is increasing more than anticipated. Investigations into the growing admissions to sheltered workshops resulted in recommendations to improve the practice of change over. More and more admissions of students having finished special schools could be reduced by improved cooperation between special schools and the local employment market. Special schools should offer suitable job trainings and support students to develop an understanding of the requirements of specific jobs and of their opportunities to develop their skills to do these jobs. In 2009, supported employment has been regulated in social security law, lasting up to three years and aimed at qualifying disabled youngsters for employment in the general labour market instead of entering sheltered workshops. The majority of admissions to sheltered workshops in the meantime concern people with psychological handicaps, with more than 30% however leaving the workshops later on. For this population, "virtual sheltered workshops" are offering more suitable means for reintegration in the general labour market, such as temporary employment in the general labour market or in occupations with small earnings. The personal budget for work is meant to be a model project within the German Länder, to transfer personal support from the sheltered workshop into the general labour market. The conference of German Länder Ministers of Social Affairs has been active since 2007 to develop a concept for reform of the social security law concerning integration assistance for disabled people, which in future is to concentrate on individual needs, removal of obstacles in the law to facilitate the transition from sheltered workshops into the general labour market. The "Deutsche Verein für öffentliche und private Fürsorge" (German association for public and private welfare) has contributed valuable suggestions to the reform debate, all of which should be realized by the German Government during the seventeenth legislative period.


Assuntos
Redes Comunitárias/organização & administração , Pessoas com Deficiência/reabilitação , Emprego/organização & administração , Reforma dos Serviços de Saúde/organização & administração , Oficinas de Trabalho Protegido/organização & administração , Alemanha , Humanos
15.
HNO ; 58(1): 57-62, 2010 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-20033119

RESUMO

Aneurysmal bone cyst is a benign osteolytic lesion in childhood and adolescence which primarily arises in metaphyseal long bones. Its presence in bones of the skull base is very rare. In a 3-year old girl presenting with proptosis, MRI demonstrated a well-defined displacing growing mass in the ethmoid sinus, orbita and anterior fossa. The histopathologic examination of biopsy specimens confirmed an aneurysmal bone cyst. Despite radical surgery the child suffered from two recurrences of the lesion in the first year after initial diagnosis. There has been no subsequent recurrence during the last 3 years. Since this lesion is rarely seen at the skull base, is difficult to differentiate clinically and by histopathology and may take an abnormal course, it is described in this case report to emphasize that it should be included in the differential diagnosis of ENT tumors at this location.


Assuntos
Cistos Ósseos Aneurismáticos/diagnóstico , Cistos Ósseos Aneurismáticos/terapia , Pré-Escolar , Diagnóstico Diferencial , Osso Etmoide , Feminino , Humanos , Doenças Raras/diagnóstico , Doenças Raras/terapia , Base do Crânio , Neoplasias da Base do Crânio/diagnóstico , Neoplasias da Base do Crânio/terapia
16.
HNO ; 57(2): 135-41, 2009 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-18825354

RESUMO

BACKGROUND: Small cell carcinoma of the larynx is a rare, poorly differentiated neuroendocrine carcinoma (NEC). It is often diagnosed late, with delayed initiation of adequate therapy. PATIENTS AND METHODS: The data for eight patients were retrospectively analyzed with regard to clinical information, surveillance, and diagnostic and therapeutic strategies. RESULTS: The histopathologic diagnosis was made after a mean of 2.88+/-2.52 months after the first symptoms occurred. Staging and exclusion of an extralaryngeal primary was completed 1.75+/-1.7 months after the histological diagnosis. Seventy-five percent (n=6) of the patients already had regional or systemic metastases. Systemic metastases were detected in 50% (n=4) of the patients by FDG-positron emission tomography/computed tomography. Primary (n=4) or postoperative (n=3) radiochemotherapy was performed 3.07+/-1.32 months after initial diagnosis. Overall survival (n=6) was 12.83 +/-3.76 months. CONCLUSION: Studies providing high-level evidence cannot be expected because of the low incidence of small cell NEC. Efficient diagnosis should be followed immediately by combined radiochemotherapy. As with small cell bronchial carcinoma, small cell NEC of the larynx should be regarded as a systemic disease and be treated in a similar way.


Assuntos
Carcinoma Neuroendócrino/diagnóstico , Carcinoma Neuroendócrino/terapia , Neoplasias Laríngeas/diagnóstico , Neoplasias Laríngeas/terapia , Carcinoma Neuroendócrino/patologia , Carcinoma Neuroendócrino/secundário , Diferenciação Celular , Humanos , Neoplasias Laríngeas/patologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Resultado do Tratamento
17.
18.
Invest Ophthalmol Vis Sci ; 42(6): 1328-37, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11328747

RESUMO

PURPOSE: For macular translocation surgery, the native attached retina has to be detached either locally or completely. Although different surgical techniques are used, there is a general search for supporting procedures that facilitate and accelerate the retinal detachment. METHODS: Pars plana vitrectomies were performed in pigmented rabbits. In all experimental groups, a local retinal detachment was created by infusing the test solution with a thin glass micropipette attached to a glass syringe. In control animals a standard balanced salt solution was used at room temperature, in combination with a standard vitrectomy light source. In two test groups, a calcium- and magnesium-free solution was used for the vitrectomy, under illumination by a standard light source in group I (solution at room temperature) and group II (solution heated up to body temperature). In group III the rabbits were dark-adapted for half an hour, and then, during surgery, a red filter was used in front of the light source (standard balanced salt solution at room temperature). After the rabbits were killed at the end of surgery, the adherence of the retinal pigment epithelium (RPE) to the neural retina in the detachment area was quantified microscopically, and the morphologic integrity of the detached retinal tissue was examined by light and electron microscopy. No electrophysiology was performed. RESULTS: In all four groups, it was possible to detach the retina. The maximum adherence of the RPE cells to the neural retina was observed in the control group. Virtually no decrease in adherence was found in test group II (36 degrees C solution without calcium and magnesium), whereas a significant decrease was seen in both group I (calcium- and magnesium-free solution at room temperature) and group III (dark adaptation-red light technique; standard balanced salt solution at room temperature). In none of the experimental groups was any obvious damage of the retinal structure observed, even after exposure to the test solutions for 60 minutes. CONCLUSIONS: Both dark adaptation (red illumination) and the use of a calcium chloride- and magnesium chloride-free solution (at room temperature) can facilitate retinal detachment in macular translocation surgery. Both techniques are proposed as a gentle support for the operation, because they protect an intact RPE cell layer and do not cause retinal damage at the ultrastructural level.


Assuntos
Macula Lutea/transplante , Procedimentos Cirúrgicos Oftalmológicos , Descolamento Retiniano/cirurgia , Animais , Bicarbonatos/efeitos adversos , Temperatura Corporal , Cloreto de Cálcio , Adesão Celular , Adaptação à Escuridão , Combinação de Medicamentos , Feminino , Glutationa/efeitos adversos , Macula Lutea/ultraestrutura , Cloreto de Magnésio , Masculino , Microscopia Eletrônica de Varredura , Soluções Oftálmicas , Epitélio Pigmentado Ocular/patologia , Coelhos , Descolamento Retiniano/induzido quimicamente , Descolamento Retiniano/patologia , Transplante de Tecidos/métodos , Vitrectomia
19.
Biomaterials ; 17(13): 1327-32, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8805981

RESUMO

The purpose of this investigation was to test the effect of an enzymatic and an acidic medium on in vitro wear of dental resin composites and an amalgam. Wear was evaluated in two-body and three-body wear conditions. The third body was a food slurry either in water, an esterase solution or an acid solution at a composition and concentration as found in caries active plaque fluid. In the two-body tests the slurry was left out. Under three-body wear conditions neither the enzyme nor the acids showed any significant (P < 0.05) effect on wear. Enzyme inactivation from a large excess of food constituents in the slurry or the absence of an effect from surface diffusion rates of the acids resulted in the lack of an effect on wear. The two-body/acids wear rates were statistically (P < 0.05) lower than the two-body/water wear rates caused by increased lubrication from the acids between sliding surfaces. A significant (P < 0.05) increase in wear was found in the two-body/enzyme experiments, showing that the enzymatic activity can start directly at the outer surface of the composites.


Assuntos
Resinas Compostas/metabolismo , Ácidos/metabolismo , Resinas Compostas/química , Amálgama Dentário/metabolismo , Cárie Dentária/metabolismo , Placa Dentária/metabolismo , Esterases/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Teste de Materiais , Propriedades de Superfície
20.
Diagn Microbiol Infect Dis ; 12(4): 315-8, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2556235

RESUMO

A new FITC-conjugated HSV specific monoclonal antibody reagent (Syva Co., Palo Alto, Ca) was evaluated for the confirmation of HSV clinical isolates. The reagent was also compared to type-specific monoclonal antibodies for the pre-CPE detection of HSV from clinical specimens in centrifugation culture and by direct examination of specimens smears by direct immunofluorescent antibody staining (DFA). HSV was isolated from 75 of 232 specimens (32%). All 75 isolates were confirmed with both the type-specific antibodies and the HSV-specific reagent. In centrifugation culture HSV was detected in 36 of 105 (34%) specimens. The HSV specific reagent detected all 36 specimens that were positive with the type-specific reagents. HSV infection was diagnosed by DFA in 31 of 50 (62%) specimen smears. The HSV-specific reagent detected all 31 positive specimens. This reagent confirmed and detected all HSV positive specimens that were positive by the type-specific monoclonal antibody reagents. The reagent contains monoclonal antibodies specific for both HSV1 and HSV2 in a single mixture, which produces a highly sensitive HSV FA staining reagent.


Assuntos
Anticorpos Monoclonais , Herpes Simples/diagnóstico , Simplexvirus/imunologia , Anticorpos Antibacterianos , Especificidade de Anticorpos , Estudos de Avaliação como Assunto , Imunofluorescência , Humanos , Indicadores e Reagentes
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA