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1.
Clin Oral Investig ; 18(3): 847-56, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23900792

RESUMO

OBJECTIVES: Cells with stem/progenitor properties have been detected in major salivary glands, but no data are available on their presence within minor salivary glands (MSGs). This study aimed to isolate and characterize potential stem/progenitor cells from human MSGs. MATERIALS AND METHODS: MSGs of the lower lip were surgically obtained during biopsy for Sjogren's syndrome investigation that finally proved to be histologically normal. The established MSG cultures were assessed for morphology, proliferation, colony-forming-unit efficiency, multipotentiality, and immunophenotypic characteristics. RESULTS: A mixed population of fibroblast-like and a few flat-shaped epithelial-like cells was obtained. These cells were capable for osteogenic, adipogenic, and neurogenic differentiation. Evidence for strong stem cell potency was observed by the detection of early stem cell markers, like Nanog, Oct-3/4, and SSEA-3. These cells also expressed characteristic mesenchymal stem cell markers, including CD90-Thy1, CD105, CD49f, CD81, nestin, CD146, and Stro-1, but were negative for CD117/C-KIT, CD45, and CD271/NFG. In addition, positivity for keratins 7/8 in part of the population was indicative of an epithelial phenotype, whereas these cells were negative for aquaporin-1 expressed in acinar/myoepithelial cells during development. CONCLUSIONS: Based on these data, a cell population with stem/progenitor characteristics was primarily isolated from labial MSGs. The morphologic and immunophenotypic features indicated that this population is mixed with mesenchymal (mainly) and epithelial characteristics. CLINICAL RELEVANCE: Due to their large number and superficial distribution in labial mucosa, MSGs may be proposed as a potential easily accessible source of adult stem/progenitor cells for regenerative therapies of glandular organs with parenchymal pathology.


Assuntos
Lábio/citologia , Glândulas Salivares/citologia , Células-Tronco/citologia , Feminino , Humanos , Imunofenotipagem , Lábio/imunologia , Pessoa de Meia-Idade , Glândulas Salivares/imunologia , Células-Tronco/imunologia
2.
Data Brief ; 48: 109274, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37383786

RESUMO

Large sample datasets of in situ evapotranspiration (ET) measurements with well documented data provenance and quality assurance are critical for water management and many fields of earth science research. We present a post-processed ET oriented dataset at daily and monthly timesteps, from 161 stations, including 148 eddy covariance flux towers, that were chosen based on their data quality from nearly 350 stations across the contiguous United States. In addition to ET, the data includes energy and heat fluxes, meteorological measurements, and reference ET downloaded from gridMET for each flux station. Data processing techniques were conducted in a reproducible manner using open-source software. Most data initially came from the public AmeriFlux network, however, several different networks (e.g., the USDA-Agricultural Research Service) and university partners provided data that was not yet public. Initial half-hourly energy balance data were gap-filled and aggregated to daily frequency, and turbulent fluxes were corrected for energy balance closure error using the FLUXNET2015/ONEFlux energy balance ratio approach. Metadata, diagnostics of energy balance, and interactive graphs of time series data are included for each station. Although the dataset was developed primarily to benchmark satellite-based remote sensing ET models of the OpenET initiative, there are many other potential uses, such as validation for a range of regional hydrologic and atmospheric models.

3.
J Autism Dev Disord ; 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36484963

RESUMO

Gender dysphoria (GD) and Autism Spectrum Disorder (ASD) co-occur relatively often, but there is no evidence-based treatment for this specific group. Therefore, we examined the effects of a group intervention for adolescents with ASD and GD in a pilot study with a pre-post-test design. The adolescents completed questionnaires on quality of life, self-esteem, gender dysphoric feelings, and social responsiveness. Results show that participating in this peer support group seems to increase aspects of quality of life, i.e., increased parent-reported psychological well-being and decreased psychological complaints. Even though more research is needed, these results indicate that peer support is an invaluable part of treatment for adolescents with ASD and GD.

4.
Eur J Orthod ; 31(1): 46-50, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19073954

RESUMO

The aim of this study was to determine whether a force applied in an antero-posterior direction would adequately reduce incisor eruption. This is needed to achieve a constant direction of force which is one of the demands for a good model for studying orthodontic tooth movement. Twenty male Wistar rats aged 11-12 weeks were divided into two equal groups: in the appliance group, a superelastic closed coil spring (25 cN) was placed between the upper left first molar and the incisors. The control group consisted of animals without an appliance. In both groups, cuts were created on the labial surfaces of the upper and lower incisors. The distance from the gingival reference point to the midpoint of the cut was measured for 10 days at 2 day intervals. Upper incisor inclination was determined as the distance from the most mesial point of the upper left first molar to the incisal edge of the ipsilateral incisor on days 0 and 10. Statistical analysis was carried out using two-way analysis of variance and a Bonferroni post- test to estimate reliability. The eruption rates of the maxillary incisors in the appliance group were significantly decreased when compared with the control group during the whole experiment. In the appliance group, the eruption rates of the mandibular incisors were decreased more than those of the maxillary incisors (P<0.01). There was no difference in incisor inclination between the appliance and control groups on day 10 (P=0.81). The applied force of 25 cN in an antero-posterior direction diminished incisor eruption to a level which enabled a constant direction of orthodontic force for 10 days.


Assuntos
Incisivo/fisiopatologia , Erupção Dentária/fisiologia , Técnicas de Movimentação Dentária , Animais , Masculino , Modelos Animais , Desenho de Aparelho Ortodôntico , Fios Ortodônticos , Ratos , Ratos Wistar , Estresse Mecânico , Fatores de Tempo , Técnicas de Movimentação Dentária/instrumentação
5.
Dent Mater ; 34(3): 519-530, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29373133

RESUMO

OBJECTIVES: Camphorquinone (CQ) is the most important photoinitiator used in dental composite resins. Sparse data indicate a mutagenic potential of CQ. Therefore, it was aim of this study to evaluate the cytotoxicity, genotoxicity, and mutagenicity of CQ in L5178Y TK+/- mouse lymphoma cells. METHODS: L5178Y/TK+/- cells were exposed to different concentrations of non-irradiated CQ (0.25-2.5mM). Cytotoxicity was evaluated by propidium iodide assay, determination of suspension growth rate, relative total growth and the mitotic index. Intracellular levels of reactive oxygen/nitrogen species (ROS/RNS) were quantified by 2',7'-dichlorofluoresceine diacetate (DCFH-DA). Early induction of DNA strand breaks and oxidative DNA base lesions was assessed using the 8-hydroxyguanine DNA-glycosylase 1 (hOGG1)-modified alkaline comet assay, whereas mutagenicity of CQ was determined in the mouse lymphoma TK assay (MLA), according to OECD Guideline No. 490. RESULTS: CQ (0.5-2.5mM) induced concentration- and time-dependent inhibition of cell growth associated with increased ROS/RNS production, amounting to 2342%±1108% of controls after 90min at 2.5mM. Additionally, CQ concentration-dependently caused direct DNA-damage, i.e. formation of DNA strand breaks and 8-hydroxy-2'-deoxyguanosine. Whereas the MLA indicated lack of mutagenicity of CQ after a 4h of treatment, CQ concentration-dependently increased total mutant frequency (MF) after 24h (about 2-fold at 2.5mM). But, based on the global evaluation factor concept, increase in MF did not reach biologically relevance. SIGNIFICANCE: CQ induced concentration-dependent, cytotoxic and genotoxic effects in L5178Y/TK+/- cells, most likely due to oxidative stress, but without mediating obvious biological relevant mutagenicity.


Assuntos
Cânfora/análogos & derivados , Células Tumorais Cultivadas/efeitos dos fármacos , Animais , Cânfora/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Ensaio Cometa , Dano ao DNA/efeitos dos fármacos , Técnicas In Vitro , Linfoma , Camundongos , Índice Mitótico , Testes de Mutagenicidade , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo
6.
Dent Mater ; 22(6): 499-505, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16198408

RESUMO

OBJECTIVES: Oral and systemic cells are permanently exposed to various types of xenobiotics, such as dental restorative materials, which may subsequently cause adverse effects. Objective of the present investigation was to analyze the effects of three important resin monomers on the glutathione metabolism of human gingival fibroblasts after an incubation period of 4h. METHODS: Cells were exposed to various concentrations of 2-hydroxyethyl methacrylate (HEMA; 0.1-10 mM), triethylene-glycol dimethacrylate (TEGDMA; 0.05-2.5 mM), and urethane dimethacrylate (UDMA; 0.005-0.25 mM). Subsequently, cellular glutathione (GSH) concentrations were determined after a treatment period of 4h using the monobromobimane assay. Data were statistically evaluated using Tukey ANOVA with p<0.05. RESULTS: GSH depletion was dependent on the type of the resin monomer: UDMA>TEGDMA>HEMA. The concentrations for a 50%-reduction of cellular GSH varied between 0.1 mM (0.05 mM) (UDMA), 0.33 mM (0.09 mM) (TEGDMA), and 1.6 mM (0.8 mM) (HEMA). Simultaneously, no decrease of cell numbers was found at any tested concentration. SIGNIFICANCE: These data indicate that the investigated resins may cause cell damage due to depletion of intracellular GSH level even at low concentrations within a short period of time. The decrease of GSH is an early reaction, which is triggered prior to other cytotoxic alterations.


Assuntos
Resinas Compostas/farmacologia , Materiais Dentários/farmacologia , Fibroblastos/efeitos dos fármacos , Gengiva/efeitos dos fármacos , Glutationa/efeitos dos fármacos , Metacrilatos/farmacologia , Polietilenoglicóis/farmacologia , Ácidos Polimetacrílicos/farmacologia , Poliuretanos/farmacologia , Cimentos de Resina/farmacologia , Compostos Bicíclicos com Pontes , Contagem de Células , Células Cultivadas , Relação Dose-Resposta a Droga , Fibroblastos/metabolismo , Corantes Fluorescentes , Gengiva/metabolismo , Glutationa/análise , Humanos , Teste de Materiais , Reagentes de Sulfidrila
7.
J Environ Qual ; 35(5): 1742-55, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16899745

RESUMO

A detailed study of water and nitrogen (N) discharge from a small, representative subwatershed of Rehoboth Bay, Delaware, was conducted to determine total N loads to the bay. The concentrations of ammonium (NH4(+)), nitrate + nitrite (NO3(-) + NO2(-)), and dissolved and particulate organic N were determined in baseflow and storm waters discharging from Bundicks Branch from October 1998 to April 2002. A novel hydrographic separation model that accounts for significant decreases in baseflow during storm events was developed to estimate N loads during unsampled storms. Nitrogen loads based on gauged flows alone (7100-19,100 kg/yr) significantly underestimated those based on land use-land cover (LULC) and estimated N export factors from different classes of LULC (32,000-40,600 kg/yr). However, when ungauged underflow and associated N loads were included in the total loads (25,500-33,800 kg/yr), there was much better agreement with LULC export models. This suggests that in permeable coastal plain sediments, underflow contributes significantly to N fluxes to estuarine receiving waters, particularly in drier years. Based on the similarity in LULC, N loads from the Bundicks Branch subwatershed were used to estimate upland loads to the entire Rehoboth Bay Watershed (259,000-316,000 kg/yr). These N loads from the watershed were much greater than those from direct atmospheric deposition (49,000-64,500 kg/yr) and from a local wastewater treatment plant (9700-13,700 kg/yr). While the watershed was the principal source of N at all times during the year, the relative contributions from the watershed, wastewater, and direct atmospheric deposition varied predictably with season.


Assuntos
Monitoramento Ambiental , Modelos Teóricos , Nitrogênio/análise , Poluentes da Água/análise , Delaware , Monitoramento Ambiental/métodos , Estações do Ano
8.
J Biomed Mater Res B Appl Biomater ; 75(2): 272-6, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16080163

RESUMO

Glutathione (GSH) is important for the self-protection of cells against oxidative stress and toxic xenobiotics, whereas reactive oxygen species (ROS) at elevated concentrations may cause detrimental alterations of cell membranes, DNA, and other cellular structures. The present investigation addressed the effects of triethylene-glycoldimethacrylate (TEGDMA) and camphorquinone (CQ) on glutathione metabolism and the formation of ROS in oral cells. Primary human pulp fibroblasts were exposed to various concentrations of TEGDMA and CQ (0.1-5 mM). Subsequently, GSH concentration and ROS formation were analyzed with the use of the monobromobimane assay (GSH) and 2',7'-dichlorofluorescein diacetate (DCFH-DA) (ROS). The endogenous ROS hydrogen peroxide (H2O2) was used as a positive control (0.02-2 mM). TEGDMA significantly decreased GSH at concentrations between 0.5 and 5 mM (p<0.05), but did not elevate ROS levels. Contrary, CQ increased ROS formation at concentrations>or=1 mM, but had only a moderate effect on GSH at the highest test concentration. Hydrogen peroxide increased ROS and simultaneously decreased GSH at concentrations of >or=0.2 mM. These data show that the investigated substances may cause cell damage due to various mechanisms, GSH decrease and/or ROS increase. As a consequence, TEGDMA and CQ released into an aqueous environment from resinous materials might interact, thus generating significant cytotoxic effects even at low concentrations.


Assuntos
Polpa Dentária/citologia , Polpa Dentária/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Glutationa/metabolismo , Polietilenoglicóis/farmacologia , Ácidos Polimetacrílicos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Terpenos/farmacologia , Células Cultivadas , Humanos
9.
Clin Pharmacol Ther ; 27(5): 697-703, 1980 May.
Artigo em Inglês | MEDLINE | ID: mdl-7371367

RESUMO

Six male subjects received simultaneously single 50-mg oral doses of a maprotiline hydrochloride tablet and a trideuterated maprotiline hydrochloride aqueous solution. No side effects or other problems were encountered. The blood levels of unlabeled and isotope-labeled maprotiline for each subject were essentially superimposable. Peak levels, averaging about 50 ng/ml, were attained between 8 and 24 hr after drug. The biologic t1/2 (beta-phase) averaged 58 hr for the unlabeled and 60.5 hr for the labeled drug. The total areas under the curves (extended to time infinity) averaged 3,862 and 3,944 ng . hr/ml for maprotiline and trideuterated maprotiline, respectively (differences between the two are not significant). At the 95% degree of confidence the Westlake confidence limits show less than 10% differences between the formulations with respect to area under the curve data (calculated both to 168 hr and extended to time infinity), peak blood levels, and biologic t1/2s. There were no differences between formulations with respect to times of peak concentrations. Estimates were made for apparent volumes of distribution (about 1,000 l), apparent blood clearance (about 14 l/hr), lag times (about 1.42 hr for tablets and 1.31 hr for solution), and absorption rate constants (about 0.34 hr-1 for the tablets and 0.42 hr-1 for the solution).


Assuntos
Antracenos/metabolismo , Maprotilina/metabolismo , Adulto , Disponibilidade Biológica , Humanos , Absorção Intestinal , Cinética , Masculino , Maprotilina/administração & dosagem , Maprotilina/sangue , Pessoa de Meia-Idade , Soluções , Comprimidos
10.
Eur J Cancer ; 38(6): 807-13, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11937315

RESUMO

A randomised, open label phase II study was performed in patients with advanced colorectal cancer to evaluate the safety, toxicity and antineoplastic activity of the topoisomerase I-inhibitor rubitecan. A cross-over design was chosen to determine the intrapatient variation of the bioavailability and pharmacokinetics of the anticancer agent depending on the timing of food intake in relation to the oral drug administration. Patients with previously untreated metastatic disease received two single oral doses of rubitecan 1.5 mg/m2 for assessment of the pharmacokinetics. They were randomised to have the first administration either after an overnight fasting period or immediately after a high calorie breakfast, and crossed over to the alternative schedule after a one-week washout period. After completion of the pharmacokinetic sampling, treatment continued with rubitecan given orally at a dose of 1.5 mg/m2/day, to be increased up to 2.0 mg/m2/day, under fasting conditions for 5 consecutive days per week until disease progression. 19 patients entered the trial after informed consent was obtained. A total number of 35 treatment cycles (median 2, range 1-4) were administered. All patients were evaluable for safety. The toxicity profile of rubitecan was generally mild to moderate, with sporadic cases of grade 4 toxicities (Common Toxicity Criteria (CTC) version 2.0) diarrhoea, leucopenia and neutropenia. None of 15 evaluable patients achieved an objective response. The majority had early disease progression. 14 patients were evaluable for pharmacokinetic analysis. The bioavailability of rubitecan was found to be strongly dependent on the timing of food intake with a fasted-to-fed ratio for C(max) of 1.98 (two-tailed P<0.001; ANOVA), T(max) 0.49 (P<0.001), AUC(0-8 h) 2.52 (P<0.001) and AUC(0-24 h) 1.64 (P=0.003). Rubitecan is well tolerated, but clinically inactive in colorectal cancer at the currently recommended dose and schedule. The bioavailability is strongly dependent on the timing of food intake in relation to the oral administration of the drug. The topoisomerase I-inhibitor should be administered under fasting conditions to achieve adequate drug exposure in future prospective trials in other tumour types.


Assuntos
Antineoplásicos/uso terapêutico , Camptotecina/análogos & derivados , Camptotecina/administração & dosagem , Camptotecina/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Ingestão de Alimentos/fisiologia , Administração Oral , Adulto , Idoso , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/farmacocinética , Disponibilidade Biológica , Camptotecina/farmacocinética , Estudos Cross-Over , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica
11.
J Affect Disord ; 25(4): 261-9, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1430662

RESUMO

68 patients with affective disorders, and receiving lithium prophylaxis in a specialized lithium clinic were followed up for 8 years on average. Patients were selected for this study according to 2 criteria: They had been given lithium for at least 12 months, and they had attempted suicide at least once before onset of lithium prophylaxis. Outcome was analysed in terms of suicidal and parasuicidal behaviour. 55 patients took their lithium regularly, 13 discontinued or dropped the medication. One third of those patients having discontinued the medication died from suicide. Only one suicide occurred in patients with regular lithium intake and proven compliance during the last check before death. An impressive drop of parasuicides was observed in responders as well as in apparent non-responders. In total, 11 of 13 patients showed suicidal or parasuicidal behaviour 2 weeks-44 months after lithium discontinuation, which in about half of these cases took place on advice or with consent of the treating psychiatrist. It is concluded that lithium may have specific anti-suicidal properties, possibly related to its anti-aggressive effect, and that patients apparently not responding satisfactorily in terms of reduced number of episodes may still be protected against suicide or parasuicide.


Assuntos
Transtornos Psicóticos Afetivos/psicologia , Lítio/uso terapêutico , Prevenção do Suicídio , Tentativa de Suicídio/prevenção & controle , Adulto , Transtornos Psicóticos Afetivos/tratamento farmacológico , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Suicídio/psicologia , Tentativa de Suicídio/psicologia
12.
AIDS Educ Prev ; 13(6): 495-508, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11791782

RESUMO

This study examined specific cultural beliefs and knowledge about HIV as well as tested components of the Health Belief Model in relation to condom use in Kisumu, Kenya. Interviews were conducted with 223 participants at six governmental and private clinics. Although 75% had engaged in intercourse during the preceding month, fewer than 20% had used a condom. For both men and women, perceived barriers was the only component of the Health Belief Model significantly associated with condom use, with greater perceived barriers being associated with lower frequency of condom use (p < .05). Additionally, individuals with more education and HIV/AIDS knowledge were less likely to endorse stigmatizing beliefs toward HIV/AIDS (p < .001), whereas people who believe that HIV originated in the United States were more likely to endorse these stigmatizing beliefs (p <.002). Nearly everyone (97%) reported that AIDS is the disease that scares them most, suggesting that educational efforts have successfully communicated the severity of this disease. Future intervention efforts must now focus more extensively on addressing stigmatizing beliefs and providing education to overcome barriers to condom use.


Assuntos
Preservativos/estatística & dados numéricos , Infecções por HIV/prevenção & controle , Adolescente , Adulto , Feminino , Infecções por HIV/psicologia , Comportamentos Relacionados com a Saúde , Educação em Saúde , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Quênia , Masculino , Pessoa de Meia-Idade , Modelos Psicológicos , Análise de Regressão , Fatores Sexuais , Comportamento Sexual , Inquéritos e Questionários
13.
J Pharm Sci ; 65(4): 525-9, 1976 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1271251

RESUMO

Substituted s-triazines were prepared by the treatment of biguanides with various organic acid anhydrides. This reaction permits the ready conversion of the hypoglycemic drugs phenformin, buformin, and metformin and of other analogous biguanides into compounds suitable for GC and mass fragmentographic determination with a high degree of sensitivity. Mass spectral data and Kováts retention indexes are presented for all s-triazines prepared for this study.


Assuntos
Biguanidas , Triazinas/síntese química , Biguanidas/análise , Química Farmacêutica , Métodos , Triazinas/análise
14.
J Pharm Sci ; 68(2): 156-60, 1979 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-423081

RESUMO

14C-Phenformin hydrochloride was used for investigating the metabolism, plasma or serum levels, and elimination of the drug following 1.5-mg/kg po or iv doses to guinea pigs, rats, and dogs. The amounts of individual metabolites and unchanged drug were assessed in urine as well as in plasma or serum. The glucuronide of 1-(p-hydroxyphenethyl)biguanide was a major metabolite in the blood and urine of all three species. Guinea pig serum and urine contained a sizable quantity of unchanged drug. Dog plasma and urine had significant amounts of nonconjugated 1-(p-hydroxyphenethyl)biguanide and of an unidentified major metabolite. In all three species following intravenous drug administration, unchanged drug contributed significantly to the radioactivity found in blood and urine. The apparent half-lives of phenformin eliminateion were 0.3-0.8 day for guinea pigs and rats and 1-1.5 days for dogs. Urinary excretion data indicate apparent half-lives of approximately 1.3-1.5 days for the elimination of each of the three major metabolites in dogs.


Assuntos
Fenformin/metabolismo , Animais , Autorradiografia , Cromatografia Gasosa , Cromatografia em Camada Fina , Cães , Fezes/análise , Cobaias , Masculino , Fenformin/sangue , Fenformin/urina , Ratos , Especificidade da Espécie
15.
Arch Pathol Lab Med ; 112(2): 128-32, 1988 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3257381

RESUMO

Initial biopsy specimens from two patients with lymphadenopathy and human immunodeficiency virus antibody-positive serum presented considerable difficulty in making specific histologic and immunologic diagnoses, although subsequent biopsy specimens revealed clear progression to acquired immunodeficiency syndrome (AIDS)-associated lymphomas. The initial biopsy specimens revealed multifocal clusters of large blastic lymphoid cells, with some clusters showing a monoclonal lambda light chain predominance, whereas other clusters showed a kappa predominance, indicating considerable phenotypic ambiguity suggestive of polyclonality. This initial clonal ambiguity was followed within two to three months by overt histologic, phenotypic, and clinical malignant transformation to a diffuse high-grade monoclonal B-cell lymphoma. These data have significant implications for the clonality and pathogenesis of AIDS-associated lymphoproliferative disorders. AIDS-related lymphomas may evolve from an initial multiclonal B-cell expansion similar to that described in other severely immunosuppressed patients (eg, with posttransplantation lymphoma).


Assuntos
Síndrome da Imunodeficiência Adquirida/complicações , Linfoma/patologia , Complexo Relacionado com a AIDS/patologia , Adulto , Idoso , Antígenos de Diferenciação/análise , Linfócitos B , Células Clonais/patologia , Feminino , Humanos , Terapia de Imunossupressão/efeitos adversos , Linfonodos/patologia , Linfoma/etiologia , Linfoma/imunologia , Masculino , Imunologia de Transplantes
16.
Dis Aquat Organ ; 42(2): 153-5, 2000 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-11023255

RESUMO

The haplosporidian oyster parasite MSX (Multinucleated Sphere X) Haplosporidium nelsoni was transmitted to eastern oysters Crassostrea virginica. Hatchery-raised, MSX-free juvenile oysters were placed in upweller tanks. Water to the tanks was filtered through a screen with 1 mm2 openings and originated from the water column overlaying naturally infected oysters beds (MSX prevalence 17 to 57%). MSX was diagnosed by histopathological analysis. MSX-disease (57% prevalence) with increased mortality (19%) was observed 11 wk after the beginning of the exposure and mortality of 80% after 16 wk. The study demonstrates transmission of MSX via water-borne infectious agents capable of passing through a 1 mm filter.


Assuntos
Aquicultura/métodos , Eucariotos/fisiologia , Ostreidae/parasitologia , Animais , Connecticut
17.
Ophthalmologe ; 93(3): 237-41, 1996 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-8753984

RESUMO

Photorefractive keratectomy (PRK) by excimer laser is now a scientifically established treatment method in low and moderate myopia. In high and very high myopia, however, the formation of severe corneal haze or scars and a considerable regression of refraction remain obstacles to the use of PRK. One approach to these two problems is to perform an intrastromal keratectomy. PATIENTS AND METHOD. Between September 1992 and September 1994 intrastromal keratectomy was carried out in 42 eyes with myopia between -8.625 and -36 D. Twenty-one eyes (spherical equivalent of pre-operative refraction between -12.12 and -36 D) were treated by keratomileusis in situ, and 21 eyes (spherical equivalent of pre-operative refraction between -8.625 and -29.25 D) by intrastromal excimer laser keratectomy. Thirty-two eyes were followed up for at least 12 months. RESULTS. The post-operative refraction (spherical equivalent) ranged between +1.375 D and -5.0 D in the keratomileusis in situ group and between +1.5 D and -3.0 D in the intrastromal excimer laser keratectomy group. Nearly all patients regained their pre-operative visual acuity quickly. In the long-term follow-up (1 year) no significant regression of refraction occurred; the pre-operative visual acuity was regained in both groups after 1 year. Significant astigmatism was not induced. CONCLUSIONS. Intrastromal keratectomy is able to correct even very high myopias quite precisely and without regression of the refractive outcome. In addition, considerable haze can be avoided. For these reasons, in high and very high myopia intrastromal keratectomy seems to be superior to conventional anterior photorefractive keratectomy (PRK) by excimer laser.


Assuntos
Substância Própria/cirurgia , Miopia/cirurgia , Ceratectomia Fotorrefrativa , Complicações Pós-Operatórias/etiologia , Refração Ocular , Adulto , Feminino , Seguimentos , Humanos , Lasers de Excimer , Masculino , Pessoa de Meia-Idade , Miopia/classificação , Resultado do Tratamento , Acuidade Visual/fisiologia
18.
Arch Oral Biol ; 58(10): 1556-68, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23871383

RESUMO

OBJECTIVE: Stem Cells residing in the Apical Papilla (SCAP) of human permanent teeth represent a promising cell source for dental tissue regeneration. Therefore, the functional and molecular properties of specific subpopulations existing within heterogeneous cultures should be further investigated to give insight whether their selection could be beneficial for targeted therapeutic applications. DESIGN: In this study we extensively characterized SCAP cultures established from 10 healthy subjects, as well as their STRO-1(pos/)CD146(pos) and STRO-1(neg/)CD146(pos) subpopulations isolated with fluorescence-activated cell sorting. SCAP were analyzed for embryonic (Nanog, Oct3/4, SSEA-3, TRA-1-60), mesenchymal (STRO-1, CD146/MUC18, CD105/endoglin, CD24, CD90/Thy-1, CD81-TAPA, CD34, CD49f/a6-integrin), neural (CD271/NGFR, nestin) and hematopoietic (CD117/c-kit, CD45) stem cell (SC) markers using flow cytometry. Multipotentiality was evaluated with culture specific staining (Alizarin-Red-S, Oil- Red-O) and RT-PCR analysis for osteo/odontogenic (DSPP, BSP, ALP, osteocalcin, osteonectin, BMP-2, Runx2), adipogenic (lipoprotein-lipase-LPL) and neurogenic (Neurofilament/NFL-L, nestin, ß-tubulin-III, NCAM) markers. RESULTS: Our results showed that the STRO-1(pos)/CD146(pos) subpopulation demonstrated higher CFU efficiency and much higher expression of several embryonic and mesenchymal SC markers compared to the non-sorted SCAP. They also showed enhanced odontogenic differentiation potential, as evidenced by higher mineralization capacity and expression of osteo/odontogenic markers. By contrast, absence of STRO-1 in the STRO-1(neg)/CD146(pos) subpopulation yielded the opposite results and was associated with significant downgrading of the above-mentioned properties. CONCLUSIONS: These results suggest that STRO-1(pos)/CD146(pos) SCAP cells represent a very promising adult MSCs source with enhanced multipotent SC properties that could be easily isolated with simple flow cytometric methods to be used for tissue engineering applications.


Assuntos
Antígenos de Superfície/análise , Antígeno CD146/análise , Papila Dentária/citologia , Células-Tronco Multipotentes/fisiologia , Biomarcadores/análise , Diferenciação Celular/fisiologia , Proliferação de Células , Células Cultivadas , Meios de Cultura , Citometria de Fluxo , Humanos , Odontogênese/fisiologia , Osteogênese/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Coloração e Rotulagem
19.
Arch Oral Biol ; 56(7): 709-21, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21227403

RESUMO

OBJECTIVE: The aim of this study was to compare the in vitro osteo/odontogenic differentiation potential of mesenchymal stem cells (MSCs) derived from the dental pulp (dental pulp stem cells - DPSCs) or the apical papilla (stem cells from the apical papilla - SCAP) of permanent developing teeth. DESIGN: DPSCs and SCAP cultures were established from impacted third molars of young healthy donors at the stage of root development. Cultures were analysed for stem cell markers, including STRO-1, CD146, CD34 and CD45 using flow cytometry. Cells were then induced for osteo/odontogenic differentiation by media containing dexamethasone, KH(2)PO(4) and ß-glycerophosphate. Cultures were analysed for morphology, growth characteristics, mineralization potential (Alizarin Red method) and differentiation markers (dentine sialophosphoprotein-DSPP, bone sialoprotein-BSP, osteocalcin-OCN, alkaline phosphatase-ALP), using immunocytochemistry and reverse transcriptase-polymerase chain reaction. RESULTS: All DPSCs and SCAP cultures were positive for STRO-1, CD146 and CD34, in percentages varying according to cell type and donor, but negative for CD45. Both types of MSCs displayed an active potential for cellular migration, organization and mineralization, producing 3D mineralized structures. These structures progressively expressed differentiation markers, including DSPP, BSP, OCN, ALP, having the characteristics of osteodentin. SCAP, however, showed a significantly higher proliferation rate and mineralization potential, which might be of significance for their use in bone/dental tissue engineering. CONCLUSIONS: This study provides evidence that different types of dental MSCs can be used in tissue engineering/regeneration protocols as an approachable stem cell source for osteo/odontogenic differentiation and biomineralization that could be further applied for stem cell-based clinical therapies.


Assuntos
Polpa Dentária/citologia , Gengiva/citologia , Células-Tronco Mesenquimais/fisiologia , Odontogênese/fisiologia , Osteogênese/fisiologia , Adolescente , Fosfatase Alcalina/análise , Antígenos CD34/análise , Antígenos de Superfície/análise , Soluções Tampão , Antígeno CD146/análise , Calcificação Fisiológica/fisiologia , Técnicas de Cultura de Células , Diferenciação Celular/fisiologia , Movimento Celular/fisiologia , Proliferação de Células , Células Cultivadas , Dexametasona/farmacologia , Proteínas da Matriz Extracelular/análise , Glucocorticoides/farmacologia , Glicerofosfatos/farmacologia , Humanos , Sialoproteína de Ligação à Integrina/análise , Antígenos Comuns de Leucócito/análise , Osteocalcina/análise , Fosfatos/farmacologia , Fosfoproteínas/análise , Compostos de Potássio/farmacologia , Sialoglicoproteínas/análise , Fatores de Tempo
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