Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 71
Filtrar
1.
Eur J Appl Physiol ; 116(11-12): 2225-2236, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27650605

RESUMO

PURPOSE: The present study investigated the effects of high- versus low-quality protein supplementation on the regain of exercise performance during recovery from a period of high-intensity resistance training. METHODS: In a diet-controlled crossover study, 12 resistance-trained participants performed two identical training periods, with each training period including four sessions of high-intensity resistance exercise during 5 days, while receiving either high- or low-quality protein. Prior to and at 3, 24 and 48 h after the training periods, performance was evaluated in knee extensor and flexor isometric maximal voluntary contraction (MVC), counter-movement jumping height (CMJ), and peak and mean anaerobic power. In addition, prior to and at 48 h after the training periods, performance in time-to-exhaustion at 70 % of VO2max (TTE) was evaluated. RESULTS: After the intense training periods, decrements in the order of 4-24 % were observed for MVCext, CMJ, mean anaerobic power, and TTE. In particular for TTE, this decrement in exercise performance did not attain full recovery at 48 h post-exercise. The regain of exercise performance was not dictated by type of protein supplement. CONCLUSION: The regain of muscle strength as well as anaerobic or aerobic performances were not markedly influenced by the type of protein supplement.


Assuntos
Proteínas Alimentares/metabolismo , Treinamento Intervalado de Alta Intensidade/métodos , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Resistência Física/fisiologia , Treinamento Resistido/métodos , Administração Oral , Proteínas Alimentares/administração & dosagem , Humanos , Masculino , Proteínas Musculares , Recuperação de Função Fisiológica/fisiologia , Método Simples-Cego , Adulto Jovem
2.
BMC Prim Care ; 24(1): 206, 2023 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-37798651

RESUMO

BACKGROUND: People with a severe mental illness (SMI) have shorter life expectancy and poorer quality of life compared to the general population. Most years lost are due to cardiovascular disease, respiratory disease, and various types of cancer. We co-designed an intervention to mitigate this health problem with key stakeholders in the area, which centred on an extended consultations for people with SMI in general practice. This study aimed to1) investigate general practitioners' (GPs) experience of the feasibility of introducing extended consultations for patients with SMI, 2) assess the clinical content of extended consultations and how these were experienced by patients, and 3) investigate the feasibility of identification, eligibility screening, and recruitment of patients with SMI. METHODS: The study was a one-armed feasibility study. We planned that seven general practices in northern Denmark would introduce extended consultations with their patients with SMI for 6 months. Patients with SMI were identified using practice medical records and screened for eligibility by the patients' GP. Data were collected using case report forms filled out by practice personnel and via qualitative methods, including observations of consultations, individual semi-structured interviews, a focus group with GPs, and informal conversations with patients and general practice staff. RESULTS: Five general practices employing seven GPs participated in the study, which was terminated 3 ½ month ahead of schedule due to the COVID-19 pandemic. General practices attempted to contact 57 patients with SMI. Of these, 38 patients (67%) attended an extended consultation, which led to changes in the somatic health care plan for 82% of patients. Conduct of the extended consultations varied between GPs and diverged from the intended conduct. Nonetheless, GPs found the extended consultations feasible and, in most cases, beneficial for the patient group. In interviews, most patients recounted the extended consultation as beneficial. DISCUSSION: Our findings suggest that it is feasible to introduce extended consultations for patients with SMI in general practice, which were also found to be well-suited for eliciting patients' values and preferences. Larger studies with a longer follow-up period could help to assess the long-term effects and the best implementation strategies of these consultations.


Assuntos
COVID-19 , Medicina Geral , Transtornos Mentais , Humanos , Estudos de Viabilidade , Pandemias , Qualidade de Vida , COVID-19/epidemiologia , Transtornos Mentais/diagnóstico , Transtornos Mentais/epidemiologia , Transtornos Mentais/terapia , Encaminhamento e Consulta
3.
Pilot Feasibility Stud ; 7(1): 168, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34479646

RESUMO

BACKGROUND: People with severe mental illness (SMI) have an increased risk of premature mortality, predominantly due to somatic health conditions. Evidence indicates that primary and tertiary prevention and improved treatment of somatic conditions in patients with SMI could reduce this excess mortality. This paper reports a protocol designed to evaluate the feasibility of a coordinated co-produced care program (SOFIA model, a Danish acronym for Severe Mental Illness and Physical Health in General Practice) in the general practice setting to reduce mortality and improve quality of life in patients with severe mental illness. METHODS: The SOFIA pilot trial is designed as a cluster randomized controlled trial targeting general practices in two regions in Denmark. We aim to include 12 practices, each of which is instructed to recruit up to 15 community-dwelling patients aged 18 and older with SMI. Practices will be randomized by a computer in a ratio of 2:1 to deliver a coordinated care program or usual care during a 6-month study period. A randomized algorithm is used to perform randomization. The coordinated care program includes educational training of general practitioners and their clinical staff educational training of general practitioners and their clinical staff, which covers clinical and diagnostic management and focus on patient-centered care of this patient group, after which general practitioners will provide a prolonged consultation focusing on individual needs and preferences of the patient with SMI and a follow-up plan if indicated. The outcomes will be parameters of the feasibility of the intervention and trial methods and will be assessed quantitatively and qualitatively. Assessments of the outcome parameters will be administered at baseline, throughout, and at end of the study period. DISCUSSION: If necessary the intervention will be revised based on results from this study. If delivery of the intervention, either in its current form or after revision, is considered feasible, a future, definitive trial to determine the effectiveness of the intervention in reducing mortality and improving quality of life in patients with SMI can take place. Successful implementation of the intervention would imply preliminary promise for addressing health inequities in patients with SMI. TRIAL REGISTRATION: The trial was registered in Clinical Trials as of November 5, 2020, with registration number NCT04618250 . Protocol version: January 22, 2021; original version.

4.
J Exp Med ; 140(5): 1260-72, 1974 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-4138694

RESUMO

Macrophage-lymphocyte clusters are formed when lymph node cells and autologous peritoneal exudate cells from guinea pigs immunized with tubercle bacilli are cultured in the presence of purified protein derivative of tuberculin (PPD) for 20 h. We have studied the ultrastructure of these clusters employing transmission and scanning electron microscopy. The most simple macrophage-lymphocyte cluster consisted of one macrophage, one large central lymphocyte with a blastoid appearance attached to the macrophage with a broad area of contact, and from a few to more than 20 small peripheral lymphocytes attached to the central lymphocyte by their uropods. Some clusters were of more complex type, containing two or three macrophages or one macrophage with more than one central lymphocyte attached to the surface, but even in these clusters each peripheral lymphocyte was attached only to one central lymphocyte. By morphological criteria the peripheral lymphocytes were T lymphocytes.


Assuntos
Imunidade Celular , Linfócitos/imunologia , Macrófagos/imunologia , Tuberculina , Animais , Sítios de Ligação de Anticorpos , Membrana Celular/ultraestrutura , Células Cultivadas , Meios de Cultura , Epitopos , Feminino , Cobaias , Imunização , Técnicas In Vitro , Linfonodos/citologia , Linfócitos/ultraestrutura , Macrófagos/ultraestrutura , Masculino , Microscopia Eletrônica , Microscopia Eletrônica de Varredura , Peritônio/citologia , Linfócitos T/imunologia
5.
Nat Commun ; 10(1): 3819, 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31444341

RESUMO

Transit through the carbon liquid phase has significant consequences for the subsequent formation of solid nanocarbon detonation products. We report dynamic measurements of liquid carbon condensation and solidification into nano-onions over ∽200 ns by analysis of time-resolved, small-angle X-ray scattering data acquired during detonation of a hydrogen-free explosive, DNTF (3,4-bis(3-nitrofurazan-4-yl)furoxan). Further, thermochemical modeling predicts a direct liquid to solid graphite phase transition for DNTF products ~200 ns post-detonation. Solid detonation products were collected and characterized by high-resolution electron microscopy to confirm the abundance of carbon nano-onions with an average diameter of ∽10 nm, matching the dynamic measurements. We analyze other carbon-rich explosives by similar methods to systematically explore different regions of the carbon phase diagram traversed during detonation. Our results suggest a potential pathway to the efficient production of carbon nano-onions, while offering insight into the phase transformation kinetics of liquid carbon under extreme pressures and temperatures.

6.
J Clin Invest ; 90(1): 86-96, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1378856

RESUMO

In search for matrix proteins released from secretory vesicles of human neutrophils, a prominent 67-kD protein was identified in the extracellular medium of neutrophils stimulated by the chemotactic peptide, FMLP. The protein was purified to apparent homogeneity and partially sequenced. The sequence of the first 32 NH2-terminal amino acids was identical to the sequence of albumin. mRNA for human albumin could not be detected in bone marrow cells, nor could biosynthetic labeling of albumin be demonstrated in bone marrow cells during incubation with [14C]leucine. Immunofluorescence studies on single cells demonstrated the presence of intracellular albumin in fixed permeabilized neutrophils. Light microscopy of immunogold-silver-stained cryosections visualized albumin in cytoplasmic "granules." The morphology of these was determined by immunoelectron microscopy as vesicles of varying form and size. Subcellular fractionation studies on unstimulated neutrophils demonstrated the presence of albumin in the low density pre-gamma and gamma-regions that contain secretory vesicles, but are devoid of specific granules and azurophil granules. Albumin was readily released from these structures during activation of neutrophils with inflammatory mediators. Immunoblotting demonstrated the presence of immunoglobulin and transferrin along with albumin in exocytosed material from stimulated neutrophils. This indicates that secretory vesicles are unique endocytic vesicles that can be triggered to exocytose by inflammatory stimuli.


Assuntos
Proteínas Sanguíneas/metabolismo , Neutrófilos/metabolismo , Dextranos/metabolismo , Endocitose , Fluoresceína-5-Isotiocianato/metabolismo , Humanos , Técnicas In Vitro , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Neutrófilos/ultraestrutura , Albumina Sérica/análise , Albumina Sérica/metabolismo
7.
Int J Med Inform ; 97: 312-321, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27919389

RESUMO

BACKGROUND: Malnutrition is frequent in older people and a precursor for morbidity and hospitalisation; furthermore low intake and weight loss during and after hospitalisation is well-described. Such patients are often excluded from technology projects on account of lack of skills. This is a barrier for their access to many current and future health care offers. OBJECTIVES: To test the acceptability, feasibility and preliminary efficacy of technology-supported energy- and protein-enforced homedelivered meals for older patients discharged from hospital. DESIGN: Mixed method design including a quasi-experimental controlled feasibility trial and embedded qualitative interviews. PARTICIPANTS: Older medical patients (mean age 79.4 years; women 66.7%) at nutritional risk and discharged to own home were included consecutively to first the control group (n=18) and later the intervention group (n=18). Nine intervention and 16 control group patients completed the project. METHODS: Intervention: group received: 1) enriched meals delivered to participants' homes 12 weeks after discharge, and 2) a tablet computer combining goal setting for intake with self-monitoring and feedback. Control group were treated as usual. Data collection was done at baseline, and at six and 12 weeks follow-up. Feasibility evaluation focused on 1) inclusion and retention and 2) acceptability and functionality of the intervention. Efficacy primary endpoint: Muscle strength and BMI. Secondary: Health related quality of life (HRQoL), depression; readmissions, mortality. RESULTS: Technology challenges were related to immaturity of the out-of hospital app version; however, participants were motivated and capable of using the device. Inclusion and retention was challenged by the acceptability of the nutritional intervention and exhaustion among patients. Mortality was high. Although weaker at baseline the intervention group increased their muscle strength more consistently than did the control group: Handgrip strength with 2.5kg vs 0.9kg and chairto-stand-test with 3.3 vs. 1.8 times. They also improved their depression score and HRQoL more, and patients reported increased intake, appetite, and energy in the interviews. Relatives confirmed this and also reported positive impact on their level of worry and on the relationship with the older person. CONCLUSION: The study provided valuable insight into appropriate methods and procedures as well as older people's preferences and views on barriers to successful intervention and use of technology in health care. This will guide the design of a future sufficiently powered study. Effect evaluation provided guidance for future sample size calculation.


Assuntos
Hospitalização/estatística & dados numéricos , Desnutrição/prevenção & controle , Estado Nutricional , Alta do Paciente , Qualidade de Vida , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Ingestão de Energia , Estudos de Viabilidade , Feminino , Humanos , Masculino , Motivação
8.
Oxid Med Cell Longev ; 2016: 2492858, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26925191

RESUMO

Objective. Microvesicles (MVs) are small cell-derived particles shed upon activation. Familial hypercholesterolemia (FH) particularly when associated with Achilles tendon xanthomas (ATX) predisposes to atherosclerosis, possibly through oxLDL-C interaction with the CD36 receptor. To investigate the hypothesis that MVs derived from cells involved in atherosclerosis are increased in FH and that CD36 expressing MVs (CD36+ MVs) may be markers of oxLDL-C-induced cell activation, cell-specific MVs were measured in FH patients with and without ATX and their association with atherogenic lipid profile was studied. Approach and Results. Thirty FH patients with and without ATX and twenty-three controls were included. Plasma concentrations of MVs and CD36+ MVs derived from platelets (PMVs), erythrocytes (ErytMVs), monocytes (MMVs), and endothelial cells (EMVs), as well as tissue factor-positive cells (TF+ MVs), were measured by flow cytometry. Total MVs, MMVs, EMVs, ErytMVs, and TF+ MVs were significantly increased in FH patients, compared to controls. CD36+ MVs derived from endothelial cells and monocytes were significantly higher in FH patients and oxLDL-C predicted all the investigated cell-specific CD36+ MVs in FH patients with ATX. Conclusions. MVs derived from cells involved in atherosclerosis were increased in FH and may contribute to elevated atherothrombosis risk. The increased cell-specific CD36+ MVs observed in FH may represent markers of oxLDL-C-induced cell activation.


Assuntos
Micropartículas Derivadas de Células/metabolismo , Hiperlipoproteinemia Tipo II/metabolismo , Lipoproteínas/metabolismo , Estresse Oxidativo , Tendão do Calcâneo/patologia , Antígenos CD36/metabolismo , Feminino , Citometria de Fluxo , Humanos , Hiperlipoproteinemia Tipo II/complicações , Hiperlipoproteinemia Tipo II/patologia , Lipoproteínas LDL/metabolismo , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Xantomatose/complicações , Xantomatose/patologia
9.
Comput Methods Programs Biomed ; 135: 101-4, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27586483

RESUMO

OBJECTIVES: The Danish Blood Donor Study (DBDS) is a prospective, population-based study and biobank. Since 2010, 100,000 Danish blood donors have been included in the study. Prior to July 2015 all participating donors had to complete a paper-based questionnaire. Here we describe the establishment of a digital tablet-based questionnaire platform implemented in blood bank sites across Denmark. METHODS: The digital questionnaire was developed using the open source survey software tool LimeSurvey. The participants accesses the questionnaire online with a standard SSL encrypted HTTP connection using their personal civil registration numbers. The questionnaire is placed at a front-end web server and a collection server retrieves the completed questionnaires. Data from blood samples, register data, genetic data and verification of signed informed consent are then transferred to and merged with the questionnaire data in the DBDS database. RESULTS: The digital platform enables personalized questionnaires, presenting only questions relevant to the specific donor by hiding unneeded follow-up questions on screening question results. New versions of questionnaires are immediately available at all blood collection facilities when new projects are initiated. CONCLUSION: The digital platform is a faster, cost-effective and more flexible solution to collect valid data from participating donors compared to paper-based questionnaires. The overall system can be used around the world by the use of Internet connection, but the level of security depends on the sensitivity of the data to be collected.


Assuntos
Doadores de Sangue , Dinamarca , Feminino , Humanos , Masculino , Inquéritos e Questionários
10.
Eur J Cell Biol ; 34(1): 103-9, 1984 May.
Artigo em Inglês | MEDLINE | ID: mdl-6734621

RESUMO

In the diffuse epitheliochorial porcine placenta iron is secreted as uteroferrin by the maternal epithelium of the areola-gland subunit of the placenta. To elucidate the intracellular pathways of physiological iron in uterine gland epithelium material from 10 sows at 15 to 111 days of gestation was processed for electron microscopy by different routine methods with or without postfixation in osmium tetroxide. Ferritin particles were identified by their size and shape and the content of iron was confirmed by X-ray energy dispersive microanalysis of accumulated ferritin particles. Distinct ferritin particles were not observed in the extracellular space either basal to or luminal to the epithelial cells. Intracellular ferritin was observed apparently free in the cytoplasm, but in variable amounts. Transfer tubules and dense bodies were located basally in the secretory cells. Both of these organelles contained ferritin particles, showed reaction sites for acid phosphatase and were stained by periodic acid-thiocarbohydrazide-silver proteinate. The ciliated cells differed by having apically located dense bodies containing numerous ferritin particles. Our finding of native ferritin in cells with hormonally regulated iron transport supports the concept that transfer tubules as part of the lysosomal complex are part of the endocytic pathway in secretory cells and indicate that ferritin here is an intracellular transport or storage intermediate.


Assuntos
Ferro/metabolismo , Placenta/metabolismo , Animais , Microanálise por Sonda Eletrônica/métodos , Epitélio/metabolismo , Feminino , Microscopia Eletrônica/métodos , Placenta/ultraestrutura , Gravidez , Suínos
11.
Chest ; 80(6 Suppl): 858-60, 1981 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6975704

RESUMO

Our study was designed to examine the motility and ultrastructure of cilia from the nose of patients with Kartagener's syndrome. Microphoto-oscillographic recording from single cells showed that the patients had in fact motile cilia, although the number was reduced. Asynchrony within the single cell was a more consistent feature. The first results of blind, quantitative microscopy showed the ultrastructural defects, described earlier, but the overlapping with a normal control group was considerable. Only one of nine patients had no dynein arms and completely immotile cilia; an observation which renders the term "the immotile-cilia syndrome" a misnomer. The ear-nose-throat symptoms were characterized by daily nose-blowings since birth, recurrent sinusitis, and chronic secretory otitis media. On the other hand, the frequency of acute purulent otitis media and of common colds appeared to be normal.


Assuntos
Cílios/ultraestrutura , Síndrome de Kartagener/patologia , Mucosa Nasal/ultraestrutura , Cílios/fisiologia , Humanos , Síndrome de Kartagener/complicações , Síndrome de Kartagener/fisiopatologia , Movimento , Infecções Respiratórias/complicações
12.
APMIS ; 99(3): 219-25, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2018635

RESUMO

Lungs from rats with dexamethasone-induced Pneumocystis carinii pneumonia were examined. The ultrastructure of Pneumocystis carinii and their zone of attachment on type I alveolar epithelial cells are described. An activation of the plasmalemmal vesicular system of type I alveolar epithelial cells was observed and is described here for the first time. The significance of this observation is discussed.


Assuntos
Pneumocystis/ultraestrutura , Pneumonia por Pneumocystis/patologia , Alvéolos Pulmonares/ultraestrutura , Animais , Dexametasona , Epitélio/ultraestrutura , Microscopia Eletrônica , Membrana Nuclear/ultraestrutura , Pneumocystis/patogenicidade , Pneumonia por Pneumocystis/induzido quimicamente , Ratos , Ratos Endogâmicos
13.
APMIS ; 100(2): 188-90, 1992 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1554495

RESUMO

Pleural effusions were made by intrapleural turpentine installation in mice. The fine structure of inflammatory cells from the effusions was normal except for lipid inclusions. The same type of inclusion was previously found in neutrophils from pleural effusions in patients with tuberculous infection, rheumatoid disease, or carcinomatosis. The lipid inclusions observed in neutrophils from an irritative turpentine-induced pleurisy should be considered as "fatty change", and are structurally similar to the rheumatoid arthritis cells seen in patients with different diseases.


Assuntos
Artrite Reumatoide/patologia , Neutrófilos/ultraestrutura , Derrame Pleural/imunologia , Derrame Pleural/patologia , Pleurisia/imunologia , Animais , Humanos , Camundongos , Derrame Pleural/induzido quimicamente , Pleurisia/induzido quimicamente , Terebintina
14.
APMIS ; 99(4): 371-80, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1645170

RESUMO

Simultaneous immunocytochemical triple staining of ultrathin cryosections of herpes simplex virus type 1-infected cells was carried out using monoclonal antibodies specific for glycoprotein C, glycoprotein D and alpha + beta tubulin. The viral glycoproteins were identified in the cytoplasm, in the Golgi sacs, on the plasma membrane and on the surface of intra- and extracellular virus particles, but not on the nuclear membrane. The glycoproteins identified in the cytoplasm outside the Golgi region were not always confined to the membranes of vesicles, but were often located in close proximity to the tubulin-labelled structures. The glycoproteins C and D were usually codistributed in the cytoplasm, and both accumulated in the Golgi sacs in the same membrane domains. As the glycoproteins occur in close proximity to the microtubular structures, we speculate that these might be directly involved in the intracellular transport of viral glycoproteins.


Assuntos
Simplexvirus/análise , Proteínas do Envelope Viral/análise , Congelamento , Ouro , Técnicas Histológicas , Humanos , Imuno-Histoquímica , Simplexvirus/fisiologia
15.
APMIS ; 102(4): 279-86, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8011305

RESUMO

Receptors for urokinase-type plasminogen activator (uPAR) are present on the surface of many cell types and appear to be the key determinant controlling extracellular proteolysis catalyzed by the urokinase-type plasminogen activator (uPA). Receptor-bound uPA may be inhibited by the specific inhibitors PAI-1 and PAI-2, and the complex thus formed may subsequently be internalized and degraded in lysosomes. Biochemical evidence has recently indicated that also uPAR is internalized with the uPA/uPAI complex. We report here the subcellular localization of uPAR and cathepsin D in the MDA-MB-231 human breast cancer cell line studied by immuno-electron microscopy of ultrathin cryosections using single or double immunostaining techniques. Cell surface uPAR was preferentially localized at cell-cell junctions; cytoplasmic uPAR was inside large vesicles of different morphology and in flat Golgi saccules. A number of vesicles also contained cathepsin D. The uPAR was exclusively membrane-bound at the cell surface and in cytoplasmic vesicles without cathepsin D. In lysosomal vesicles with both cathepsin D and u-PAR, uPAR was probably degraded as it was observed in the luminal contents.


Assuntos
Catepsina D/metabolismo , Receptores de Superfície Celular/metabolismo , Compartimento Celular , Membrana Celular/metabolismo , Complexo de Golgi/metabolismo , Humanos , Imuno-Histoquímica , Técnicas Imunológicas , Microscopia Eletrônica , Receptores de Ativador de Plasminogênio Tipo Uroquinase , Células Tumorais Cultivadas
16.
APMIS ; 106(8): 771-9, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9744763

RESUMO

Pneumocystis carinii (PC) is a fungus present in the lungs of many mammal species. Even though studies of the genome, the isoenzymes, and the antigens have proved some host-species-linked heterogeneity, the existence of distinct Pneumocystis species or subspecies has still not been accepted. Comparative studies of the ultrastructural morphology of pneumocysts derived from several host species may support evidence of host-species-linked heterogeneity. We have compared the ultrastructural morphology of pneumocysts derived from mice, rats, and rabbits. The density of membrane-limited electron-dense cytoplasmic granules was found to be higher in mouse-derived pneumocysts than in rabbit-derived pneumocysts, and furthermore the average diameter of the granules from mouse pneumocysts was larger than that of granules from rabbit-derived pneumocysts. The average diameter of the filopodia of mouse-derived pneumocysts was smaller than that of filopodia from rat-derived pneumocysts, which was smaller than that of filopodia from rabbit-derived pneumocysts. Globular electron-dense bulbous dilatations at the tip of the filopodia were described for the first time and they were only found on filopodia of mouse-derived pneumocysts. These distinct host-species-linked morphological differences of pneumocysts from mouse, rat, and rabbit may support previous biochemical data indicating the existence of different Pneumocystis species or subspecies.


Assuntos
Pneumocystis/classificação , Pneumocystis/ultraestrutura , Animais , Citoplasma/ultraestrutura , Feminino , Masculino , Camundongos , Alvéolos Pulmonares/microbiologia , Alvéolos Pulmonares/patologia , Coelhos , Ratos , Especificidade da Espécie
17.
APMIS ; 103(3): 197-208, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7755976

RESUMO

The extracellular matrix is a key element in neuronal development and tumour invasion, providing a substratum which sustains the adhesion and migration of cells. In order to study interactions between the neural cell adhesion molecule (NCAM) and collagen, we transfected mouse L cells with cDNA encoding the human transmembrane NCAM isoform of 140 kDa (NCAM-B). An L-cell/collagen type I system was used to study the influence of NCAM expression on in vitro invasion. We here report that migration of NCAM-expressing cells in collagen was inhibited compared to that of NCAM-negative cells transfected with the empty vector. Immunofluorescence confocal laser scanning microscopy (CLSM) and immunogold electron microscopy using anti-human NCAM antibodies demonstrated a heterogeneous distribution of NCAM on the plasma membrane of transfected L cells grown on collagen. NCAM was preferentially located at the surface of broad cytoplasmic protrusions and slender extensions, some of which were facing the collagen. This was in contrast to the homogeneous surface distribution of NCAM on cells grown on plastic. These data suggest that NCAM and collagen type I interact, and that this might lead to the migration inhibition of NCAM-expressing cells.


Assuntos
Moléculas de Adesão Celular Neuronais/análise , Moléculas de Adesão Celular Neuronais/fisiologia , Movimento Celular/fisiologia , Colágeno , Animais , Moléculas de Adesão Celular Neuronais/genética , Movimento Celular/genética , DNA Complementar/genética , Imuno-Histoquímica , Células L , Camundongos , Microscopia Confocal , Microscopia de Fluorescência , Invasividade Neoplásica/fisiopatologia , Transfecção/genética
18.
J Pharm Sci ; 83(12): 1706-11, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7891298

RESUMO

The transepithelial transport of biosynthetic human growth hormone (hGH) formulated with the absorption enhancers didecanoyl-L-alpha-phosphatidylcholine (DDPC) and alpha-cyclodextrin (alpha-CD) was studied after intranasal administration to rabbits. Plasma concentrations of the hormone were determined until 240 min post administration by ELISA, and the absolute bioavailability was estimated to be in the vicinity of 20%. The localization of hGH was studied 15 min after application of the powder formulation in the initial absorptive phase. To visualize the hormone, a two-step indirect immuno-gold technique was used on semithin and ultrathin cryosections and Epon sections. Polyclonal rabbit anti-hGH was used as primary antibody and gold-conjugated goat anti-rabbit IgG as secondary antibody, succeeded by silver enhancement. Growth hormone was mainly found in the cytoplasm and nuclei of ciliated cells, showing distinct morphological signs of early necrosis, and in lamina propria, including the venules. Minute amounts of hGH were found in endocytotic vesicles in morphologically normal epithelial cells and in the intercellular compartment. We conclude that the major transport route of hGH formulated with absorption enhancers DDPC and alpha-CD was transcellular through lethally damaged ciliated cells.


Assuntos
Ciclodextrinas/farmacologia , Hormônio do Crescimento/farmacocinética , Mucosa Nasal/metabolismo , Fosfatidilcolinas/farmacologia , alfa-Ciclodextrinas , Absorção/efeitos dos fármacos , Administração Intranasal , Animais , Disponibilidade Biológica , Transporte Biológico , Química Farmacêutica , Interações Medicamentosas , Epitélio/metabolismo , Resinas Epóxi , Hormônio do Crescimento/administração & dosagem , Hormônio do Crescimento/sangue , Humanos , Imuno-Histoquímica , Microscopia Eletrônica , Microtomia , Coelhos
19.
Mutat Res ; 390(1-2): 121-7, 1997 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-9150760

RESUMO

The Allium anaphase-telophase assay was used to show genotoxicity of N-methyl-N-nitrosourea (MNU), maleic hydrazide (MH), sodium azide (NaN3) and ethyl methanesulfonate (EMS). All agents induced chromosome aberrations at statistically significant levels. The rank of the lowest doses with positive effect was as follows: NaN3 0.3 mg/l < MH 1 mg/l < MNU 41 mg/l < EMS 100 mg/l. The results were compared with results from other plant assays (Arabidopsis, Vicia, Tradescantia) and for MH and MNU the values were found to be within the same range, whereas the results in the Allium test for NaN3 and EMS were in a lower range than that found for the other plant assays. EMS and MMS (methyl methanesulfonate), two chemicals used as positive controls in mutagenicity testing, were compared in the Allium test, and MMS was found to be about ten times more potent in inducing chromosome aberrations than EMS. Recording of micronuclei in interphase cells showed that this endpoint does not give more information of clastogenicity than recording of chromosome aberrations in anaphase-telophase cells.


Assuntos
Allium/genética , Aberrações Cromossômicas , Testes de Mutagenicidade/métodos , Mutagênicos/toxicidade , Raízes de Plantas/genética , Allium/efeitos dos fármacos , Anáfase/efeitos dos fármacos , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Azidas/toxicidade , Relação Dose-Resposta a Droga , Metanossulfonato de Etila/toxicidade , Hidrazida Maleica/toxicidade , Metilnitrosoureia/toxicidade , Testes para Micronúcleos , Raízes de Plantas/efeitos dos fármacos , Plantas/efeitos dos fármacos , Plantas/genética , Azida Sódica , Telófase/efeitos dos fármacos
20.
Mutat Res ; 418(2-3): 113-9, 1998 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-9757013

RESUMO

Wastewater sludges were analysed in the Allium cepa genotoxicity test. They were sampled during three winter periods from three Danish municipal wastewater treatment plants differing in size and industrial load. The toxicity of the sludge was tested in the Allium root inhibition assay, and the results expressed as EC30 and EC50 values showed that the toxicity could be positive correlated to the industrial load. However, when genotoxicity was tested at concentrations corresponding to the EC30 and EC50 values in the A. cepa anaphase-telophase assay, only two sludge samples from the smallest plant with the lowest industrial load induced significant chromosome aberrations. Concentrations of the heavy metal's Pb, Ni, Cr, Zn, Cu, and Cd were also determined and could partly be correlated with the toxicity of the sludge and the industrial load of the treatment plants.


Assuntos
Aberrações Cromossômicas/genética , Metais Pesados/análise , Cebolas/genética , Esgotos/química , Poluição Química da Água/análise , Anáfase/genética , Cádmio/análise , Cromo/análise , Cobre/análise , Dinamarca , Chumbo/análise , Metanossulfonato de Metila/farmacologia , Testes de Mutagenicidade , Mutagênicos/farmacologia , Níquel/análise , Espectrofotometria Atômica , Telófase/genética , Zinco/análise
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa