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1.
Nurse Pract ; 45(7): 27-34, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32568794

RESUMO

Caries remain the most common preventable chronic childhood disease. One state oral health program including fluoride varnish showed a decrease in presence of decay and improvement in overall oral health; however, early childhood caries did not improve. Implementation of an oral health preventive program during well-child medical visits may address this gap.


Assuntos
Cárie Dentária , Saúde Bucal , Cariostáticos , Pré-Escolar , Cárie Dentária/prevenção & controle , Fluoretos , Fluoretos Tópicos , Humanos , Ciência da Implementação
2.
J Mass Spectrom ; 54(2): 148-157, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30536759

RESUMO

Comprehensive two-dimensional gas chromatography (GC × GC) coupled to time-of-flight mass spectrometry is a powerful separation tool for complex petroleum product analysis. However, the most commonly used electron ionization (EI) technique often makes the identification of the majority of hydrocarbons impossible due to the exhaustive fragmentation and lack of molecular ion preservation, prompting the need of soft-ionization energies. In this study, three different soft-ionization techniques including photo ionization (PI), chemical ionization (CI), and field ionization (FI) were compared against EI to elucidate their relative capabilities to reveal different base oil hydrocarbon classes. Compared with EI (70 eV), PI (10.8 eV) retained significant molecular ion (M+· ) information for a large number of isomeric species including branched-alkanes and saturated monocyclic hydrocarbons along with unique fragmentation patterns. However, for bicyclic/polycyclic naphthenic and aromatic compounds, EI played upper hand by retaining molecular as well as fragment ions to identify the species, whereas PI exhibited mainly molecular ion signals. On the other hand, CI revealed selectivity towards different base oil groups, particularly for steranes, sulfur-containing thiophenes, and esters, yielding protonated molecular ions (M + H)+ for unsaturated and hydride abstracted ions (M-H+ ) for saturated hydrocarbons. FI, as expected, generated intact molecular ions (M+· ) irrespective to the base oil chemical classes. It allowed elemental composition by TOFMS with a mass resolving power up to 8000 (FWHM) and a mass accuracy of 1 mDa, leading to the calculation of heteroatomic content, double bond equivalency, and carbon number of the compounds. The qualitative and quantitative results presented herein offer a unique perspective into the detailed comparison of different ionization techniques corresponding to several hydrocarbon classes.

3.
Anal Chem ; 89(10): 5395-5403, 2017 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-28410443

RESUMO

The characterization of organic mixtures by comprehensive two-dimensional gas chromatography (GC×GC) coupled to electron impact (EI) ionization time-of-flight mass spectrometry (TOF-MS) allows the detection of thousands of compounds. However, owing to the exhaustive fragmentation following EI ionization, despite the use of mass spectral libraries, a majority of the compounds remains unidentified because of the lack of parent ion preservation. Thus, soft-ionization energies leading to organic compounds being ionized with limited or no fragmentation, retaining the molecular ion, has been of interest for many years. In this study, photoionization (PI) was evaluated as the ion source for GC×GC-TOF-MS measurements. First, capabilities and limitations of PI were tested using an authentic mixture of compounds of several chemical classes. Ionization energy exhibited by PI, equivalent to 10.8 eV, resulted in significant retention of molecular ion information; [M]+• for alkanes, ketones, FAMEs, aromatics, [M-H]+• for chloroalkanes, and [M-H2O]+• for alcohols. Second, considering the potential of PI for hydrocarbons, base oils, complex mixtures of saturated and unsaturated hydrocarbons blended for finished lubricant formulations, were extensively evaluated. Several chemical classes of hydrocarbons were positively identified including a large number of isomeric compounds, both aliphatics and cyclics. Interestingly, branched-alkanes were ionized with lower excess internal energy, not only retaining the molecular ions but also exhibiting unique fragmentation patterns. The results presented herein offer a unique perspective into the detailed molecular characterization of base oils. Such unprecedented identification power of PI coupled with GC×GC-TOF-MS is the first report covering volatiles to low-volatile organic mixtures.

4.
Spec Care Dentist ; 26(2): 76-80, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16681243

RESUMO

Metastatic tumors to the oral cavity are relatively uncommon and account for about 1% of all oral cancers. Distant metastases to the jawbone are associated with a poor prognosis and a survival rate that is usually less than one year. The leading common primary sites for these lesions are the breast in females and the lung in males followed by the adrenals, kidneys, prostate, thyroid and colon. In 30% of all cancers, a metastatic lesion could be the first sign of a primary tumor elsewhere in the body. Metastatic lesions to the jaws are known to simulate periodontal and pulpal disease and other radiolucent lesions that can occur in the jaws. Microscopic evaluation with concurrent radiographic skeletal survey is warranted in patients where a metastatic lesion is suspected.


Assuntos
Adenocarcinoma/secundário , Neoplasias do Colo/patologia , Neoplasias Mandibulares/secundário , Neoplasias Primárias Desconhecidas/patologia , Adenocarcinoma/diagnóstico , Adenocarcinoma/terapia , Evolução Fatal , Feminino , Humanos , Neoplasias Mandibulares/diagnóstico , Neoplasias Mandibulares/terapia , Pessoa de Meia-Idade , Prognóstico
5.
Spec Care Dentist ; 23(2): 58-62, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14620764

RESUMO

Spontaneous gingival bleeding can occasionally be the only sign of systemic bleeding problems. The diagnosis and management of such conditions may challenge the skills of both the hematologist and the oral physician. We present this patient because of several confusing phenomena that were encountered: unprovoked periodontal hemorrhage, which endangered the life of an otherwise asymptomatic young adult male; (especially unusual was a platelet count above 150,000 cells per microliter of blood), and presentation of idiopathic thrombocytopenia purpura through spontaneous periodontal hemorrhage alone. This case history also highlights the fact that medical intervention to correct the underlying aberration of hemostasis is necessary for local dental measures to successfully stop bleeding. In contrast with the definition of thrombocytopenia, the "within normal" count of platelets should not exclude the possibility of idiopathic thrombocytopenia purpura; a fact that, if ignored, can make the diagnosis and management of bleeding troublesome.


Assuntos
Anemia/etiologia , Hemorragia Gengival/etiologia , Púrpura Trombocitopênica Idiopática/complicações , Adulto , Ácido Aminocaproico/uso terapêutico , Antifibrinolíticos/uso terapêutico , Diagnóstico Diferencial , Glucocorticoides/uso terapêutico , Hemostáticos/uso terapêutico , Humanos , Masculino , Contagem de Plaquetas , Prednisona/uso terapêutico
6.
Spec Care Dentist ; 22(4): 156-60, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12449460

RESUMO

This paper summarizes an evaluation of the Elk Mobile Dental Program for children with special health care needs. Evaluation results indicated overall client satisfaction with mobile dental unit services in the absence of competent community based dental care. Evaluator recommendations included expanding the mobile dental services along with a continued effort to establish permanent community based dental care for children with special healthcare needs. Recommendations for program improvement in the areas of patient care, service coordination, and ongoing continuous quality improvement evaluation were provided to program personnel and funding organizations. Many of the improvement recommendations were initiated during the process of the program evaluation.


Assuntos
Assistência Odontológica para Crianças , Assistência Odontológica para a Pessoa com Deficiência , Unidades Móveis de Saúde , Avaliação de Programas e Projetos de Saúde , Atitude do Pessoal de Saúde , Atitude Frente a Saúde , Criança , Prestação Integrada de Cuidados de Saúde , Auxiliares de Odontologia , Odontólogos , Grupos Focais , Humanos , Entrevistas como Assunto , Missouri , Satisfação do Paciente , Garantia da Qualidade dos Cuidados de Saúde , Gestão da Qualidade Total
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