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1.
J Emerg Manag ; 22(2): 139-154, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38695711

RESUMO

Situation awareness (SA) in complex socio-technical systems is considered a key cognitive activity, as control crews are often engaged in simultaneous task processes and are required to monitor and evaluate system parameters, making decisions and projections for the future accordingly. However, measuring SA at the team level is still a challenging area of research within the topic. In our research, we applied verbal protocol analysis as an alternative method to assess nuclear power plant control room crews' team SA. We conducted a study of 10 control room crews, examining their intrateam communication and its relatedness to team performance. We have found that communication categories related to the second and third levels of team SA increased significantly after the onset of an emergency event. Furthermore, while none of the team communication categories was related to team performance before the emergency event, all of them showed a strong positive correlation with team performance after the emergency situation occurred. Our results underline the importance of adequate verbalization of key information within the team, so as to support the rapid and accurate development of team SA during emergency situations.


Assuntos
Conscientização , Comunicação , Centrais Nucleares , Humanos , Masculino , Processos Grupais , Feminino , Adulto
2.
Lancet Reg Health Am ; 33: 100738, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38659491

RESUMO

Background: PrEP was approved for HIV prevention in the US in 2012; uptake has been slow. We describe relative equity with the PrEP Equity Ratio (PER), a ratio of PrEP-to-Need Ratios (PnRs). Methods: We used commercial pharmacy data to enumerate PrEP users by race and ethnicity, sex, and US Census region from 2012 to 2021. We report annual race and ethnicity-, sex-, and region-specific rates of PrEP use and PnR, a metric of PrEP equity, to assess trends. Findings: PrEP use increased for Black, Hispanic and White Americans from 2012 to 2021. By 2021, the rate of PrEP use per population was similar in Black and White populations but slightly lower among Hispanic populations. PnR increased from 2012 to 2021 for all races and ethnicities and regions; levels of PrEP use were inconsistent across regions and highly inequitable by race, ethnicity, and sex. In all regions, PnR was highest for White and lowest for Black people. Inequity in PrEP use by race and ethnicity, as measured by the PER, grew early after availability of PrEP and persisted at a level substantially below equitable PrEP use. Interpretation: From 2012 to 2021, PrEP use increased among Americans, but PrEP equity for Black and Hispanic Americans decreased. The US South lagged all regions in equitable PrEP use. Improved equity in PrEP use will be not only just, but also impactful on the US HIV epidemic; persons most at-risk of acquiring HIV should have the highest levels of access to PrEP. Prevention programs should be guided by PrEP equity, not PrEP equality. Funding: National Institutes of Health, Gilead Sciences.

3.
Int J Occup Saf Ergon ; 29(3): 1231-1240, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36017962

RESUMO

The aim of the study was to explore the effect of perceived team workload on team performance among nuclear fire brigades of the Hungarian nuclear power plant. Our sample consisted of six firefighting teams (N = 42 individuals) who were involved in two high-fidelity simulated scenarios with different task complexity. Team workload was measured by the NASA Task Load Index, while team performance was evaluated by a team of experts. Our results showed that teams generally managed to maintain a standard performance in both cases, although they perceived there to be a higher workload during the complex scenario. Our results further revealed that perceived 'physical demand' and 'effort' factors contributed to the increased level of workload in the complex task. Finally, in the case of the simple simulated scenario, workload and team performance were not related to each other, while the two were positively correlated in the complex scenario.


Assuntos
Análise e Desempenho de Tarefas , Carga de Trabalho , Humanos
4.
Rapid Commun Mass Spectrom ; 26(7): 759-64, 2012 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-22368055

RESUMO

RATIONALE: Pyridoxine is an important vitamer in food and pharmaceutical products. Heat treatments applied during preparation or storage of the products cause the decomposition of pyridoxine. Identification and understanding of the degradation products of pyridoxine and studying its decomposition kinetics are essential in the preparation and preservation of pyridoxine-containing foods and pharmaceuticals. METHODS: Real-time, non-isothermal decomposition of pyridoxine was studied using evolved gas analysis-Li(+) ion attachment mass spectrometry (EGA-Li(+) IAMS). Arrhenius parameters for the thermal decomposition of pyridoxine were obtained via the total ion monitoring (TIM) curve. RESULTS: Most of the pyridoxine evaporated in molecular form, but the formation of pyridoxal and o-quinone methide, both biologically important species, was also observed from the solid-phase degradation of pyridoxine. The observation of o-quinone methide, a species possessing anticancer activity, was particularly noteworthy due to its chemical instability. The activation energy (E(a) ) for pyridoxine decomposition determined by EGA-IAMS was found to be 20.0 kcal mol(-1) , and the pre-exponential factor (A) was 5.7 × 10(9) min(-1) . CONCLUSIONS: The calculated kinetic parameters are important for predicting the thermal stability of pyridoxine vitamer. The estimated lifetime (t(90%,25°C) ) of 1.7 × 10(-2) years in nitrogen was also obtained from the EGA-IAMS experiment.


Assuntos
Espectrometria de Massas/métodos , Piridoxina/química , Gases/análise , Gases/química , Temperatura Alta , Cinética , Modelos Lineares , Piridoxina/análise
5.
Psych J ; 11(1): 85-96, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34847620

RESUMO

The current cross-cultural study examined the construct of workaholism across European and Asian cultures during the pandemic caused by coronavirus disease 2019 (COVID-19). A total of 2,617 recipients, aged 18-80 years from three Asian countries (China, India, and Indonesia) with higher levels of collectivistic values, and three European countries (Bulgaria, Germany, and Hungary) supposing to have higher individualistic values. The participants completed the online version of the two-dimensional measure, dubbed the Dutch Workaholism Scale (DUWAS). The goal of the study was to demonstrate that during the COVID-19 pandemic, it is the cultural context that mediates and influences the way of change in workaholics' attitudes. The results led to the conclusion that the way in which the COVID-19 crisis affects workaholism and workaholics' behavior depends on cultural and sex differences, and stages of the human life cycle. The data analysis revealed that cultural differences and sex affect the configuration of workaholism (excessive/compulsive): in the Asian sample, unlike the European, there was a significant increase in the level of workaholism compulsive; European female participants reported higher levels of workaholism compulsive and workaholism excessive, but the sex difference was not found in Asian sample. Along with cultural context, and sex differences, age also influences the configuration of workaholism. In this case, the separate stages of the human life cycle contribute in different ways to changes in levels of workaholism excessive and workaholism compulsive.


Assuntos
Comportamento Aditivo , COVID-19 , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Comparação Transcultural , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , SARS-CoV-2 , Adulto Jovem
6.
Health Psychol Rep ; 10(3): 227-237, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-38084278

RESUMO

BACKGROUND: The present cross-cultural study examined the health locus of control construct during the COVID-19 pandemic. The scientific purpose of the study was to determine whether, during the pandemic situation, cultural and sex differences influence the health locus of control construct and change the internal health locus of control (IHLC), powerful others health locus of control (PHLC), and chance health locus of control (CHLC). PARTICIPANTS AND PROCEDURE: A total of 2617 recipients aged 18-70 years from Asia (China, India, and Indonesia), and Europe (Bulgaria, Germany, and Hungary) completed a questionnaire about their health. The participants completed an online version of the Multidimensional Health Locus of Control Scale - Form A. RESULTS: The survey shows that in a pandemic life-threatening situation, most individuals strive to rely on IHLC and/or PHLC, and fewer of them tend to rely on CHLC. However, there are differences (p < .001) between the two cultural samples: the representatives of Asian collectivistic culture are more dominated by PHLC, compared to the representatives of the European individualistic culture. When the comparison is between individuals from different cultures, sex differentiation affects the health locus of control, and as a result, significant differences in relation to IHLC, PHLC, and CHLC levels (p < .05) appear. CONCLUSIONS: In conclusion, the study indicates that cultural differences influence both the IHLC and PHLC levels, and that Asian participants are dominated by PHLC more than European respondents. Asian females are more likely to seek support from powerful others (PHLC) compared to European women, who perceive themselves as more independent. Asian male participants are prepared to rely on powerful others (doctors or medical institutions), while European male respondents are prone to rely on themselves mainly (IHLC). The results show that sex differences do not significantly affect the health locus of control within the same cultural group.

7.
AIDS Care ; 23(10): 1314-20, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21939408

RESUMO

BACKGROUND: Visiting a medical provider less frequently than clinical circumstances would suggest is appropriate has been reported to be associated with worse clinical outcomes for patients living with HIV infection. Patients with less frequent attendance to HIV care also may be systematically underrepresented in research or surveillance studies that enroll patients sequentially over a specified enrollment period - for example several months. For both reasons, understanding factors associated with time to care visit is important. METHODS: We used data from the Adult and Adolescent Spectrum of HIV Disease (ASD) project, a multi-site clinical outcomes surveillance system that enrolled and followed patients in care for HIV prospectively from 1990 to 2004. For this analysis, we used data from all patients observed in ASD at least one time before 1 January 2003, and who had at least one HIV care visit in 2003. We documented time to first annual HIV care visit for each patient, and used Kaplan-Meier plots and proportional hazards regression to describe factors associated with longer time to care visit. RESULTS: A total of 12,135 patients had ≥1 care visit during 2003 and were included in the analysis. Of these, 81%, 88%, and 95% had their first visit within three, four, and six months, respectively. In multivariate analysis, having a delayed (later) care visit was associated with not ever having had an AIDS diagnosis, having an HIV RNA concentration ≥10,000 copies/mL, having a current CD4 count <100 cells/µL, having no health insurance, and not being currently prescribed antiretroviral therapy. Having a delayed care visit was not associated with race/ethnicity or age. CONCLUSIONS: Having a delayed first annual HIV care visit was associated with higher viremia, lower CD4 cell count, and lack of health insurance. Interventions to address these factors are likely to ameliorate some of the consequences of HIV. For studies enrolling patients in care for HIV over a finite time period, an enrollment period of four-six months should sufficiently reflect the patient population seen in a one-year period, including those attending care infrequently.


Assuntos
Instituições de Assistência Ambulatorial/estatística & dados numéricos , Infecções por HIV/terapia , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Adolescente , Adulto , Contagem de Linfócito CD4 , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Fatores de Tempo , Estados Unidos , População Urbana , Carga Viral , Adulto Jovem
8.
Headache ; 51(6): 961-70, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21592098

RESUMO

OBJECTIVE: To investigate a broad definition of migraine resolution that extends beyond specific migraine-associated diagnostic symptoms as measured by the Completeness of Response Survey. METHODS: Conducted at 8 sites, 135 subjects treated migraines with SumaRT/Nap over 2 months. To measure subjects' experiences with SumaRT/Nap compared to their usual migraine medication, the Headache Impact Test, Revised Patient Perception of Migraine Questionnaire, and Completeness of Response Survey were administered at baseline and at 2 months. RESULTS: The effects of the study medicine compared to the subjects' usual migraine medicine reached statistical significance in decreasing headache severity, lessening of associated symptoms, and attaining complete relief with a single dose (60.04% of attacks resolved at 2 hours post-treatment). CONCLUSION: Compared to a subject's usual treatment, SumaRT/Nap used early and consistently for treatment of acute migraine offers important clinical improvements, including lessening of associated symptoms beyond International Headache Society criteria. CLINICAL TRIAL REGISTRATION NUMBER: NCT00893737.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Enxaqueca com Aura/tratamento farmacológico , Enxaqueca sem Aura/tratamento farmacológico , Naproxeno/administração & dosagem , Agonistas do Receptor 5-HT1 de Serotonina/administração & dosagem , Sumatriptana/administração & dosagem , Doença Aguda , Adolescente , Adulto , Idoso , Quimioterapia Combinada , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Enxaqueca com Aura/fisiopatologia , Enxaqueca sem Aura/fisiopatologia , Recuperação de Função Fisiológica , Adulto Jovem
9.
J Phys Chem A ; 115(19): 4874-81, 2011 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-21517048

RESUMO

An unknown species has been detected in the analysis of the products in a pyrolysis of polycarbonate using Li(+) ion-attachment mass spectrometry (IAMS). The mass spectra exhibited a Li(+) adduct peak at m/z 233 that was tentatively assigned to bisphenol A (BPA) biradical. Experimentally, this assignment was supported by the observation that the production rate increased under an inert nitrogen atmosphere. To further confirm the assignment, the stability of the BPA biradical to intramolecular rearrangement reactions as well as unimolecular decomposition has been analyzed via density functional theory calculations [B3LYP/6-311+G(3df,2p)]. The results show that the bisphenol A biradical is an open-shell biradical singlet that is stable to unimolecular decomposition. Although some of the proposed intramolecular rearrangement products have lower energies than those of the BPA diradical, these pathways have large reaction barriers and the kinetic lifetime of the radical is expected to be of the order of hours under the conditions of the experiment. The calculations also reveal that the bisphenol A diradical has large Li(+) affinities supporting the fact that these Li(+) complexes could be detected in the Li(+) ion attachment mass spectrometry. On the basis of these results the Li(+) adduct peak at m/z 233 detected in the pyrolysis of polycarbonate is assigned to the bisphenol A biradical.


Assuntos
Fenóis/síntese química , Cimento de Policarboxilato/química , Compostos Benzidrílicos , Radicais Livres/síntese química , Radicais Livres/química , Estrutura Molecular , Fenóis/química , Teoria Quântica , Estereoisomerismo , Termodinâmica
10.
Rapid Commun Mass Spectrom ; 24(17): 2625-30, 2010 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-20740539

RESUMO

We designed a simple evolved gas analysis (EGA) system to act as a sampler between solid samples at atmospheric pressure and the high vacuum inside a mass spectrometer. The newly designed stainless steel system is simple, small and rugged and fulfills all the basic requirements for EGA. The temperature is programmable with 60 degrees C/min as the maximum heating rate and the temperature range is up to 600 degrees C. With this system coupled with lithium ion attachment mass spectrometry (IAMS), it is possible to study the temperature-programmed decomposition of a number of solid materials by detecting any chemical species on a real-time basis. For illustrative purposes, EGA-IAMS experiments of polyethylene polymers have been conducted.

11.
Headache ; 49(10): 1402-13, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19817885

RESUMO

OBJECTIVE: To evaluate whether access to more liberal quantities of rizatriptan improves clinical outcome in patients with episodic migraine. BACKGROUND: Currently many pharmacy benefit programs limit the number of triptan tablets/injections per month based on perceived cost savings and the belief that too-frequent use of triptans may lead to medication overuse headache and headache chronification. METHODS: This observer-blind, randomized, parallel-group study enrolled 197 subjects with migraine with or without aura. Subjects completed a 3-month baseline period to establish migraine frequency and then were randomly assigned to receive 9 (formulary limit [FL]) or 27 (clinical limit [CL]) tablets of 10 mg rizatriptan orally disintegrating tablet (ODT) per month for 3 months. The primary endpoint was change in the mean number of migraine days from the baseline to treatment period. RESULTS: There was no statistically significant difference between the FL and CL groups in mean number of migraine days (FL-CL LS mean: -0.08 [-0.39, 0.23]; P = .613). Subjects in the CL group treated attacks at lower headache severity. No CL subjects were reported to have developed chronic migraine despite utilization of greater than 10 rizatriptan ODT tablets per month. Rizatriptan was generally well tolerated by both groups. CONCLUSION: Providing a greater quantity of rizatriptan ODT 10 mg did not reduce the number of migraine days compared with providing 9 tablets per month for this population with episodic migraine with a frequency of 3-8 migraines per month. Regardless of quantity provided, rizatriptan was generally well tolerated.


Assuntos
Transtornos de Enxaqueca/tratamento farmacológico , Triazóis/administração & dosagem , Triptaminas/administração & dosagem , Adolescente , Adulto , Esquema de Medicação , Feminino , Acessibilidade aos Serviços de Saúde/tendências , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos de Enxaqueca/epidemiologia , Transtornos de Enxaqueca/fisiopatologia , Satisfação do Paciente , Resultado do Tratamento , Adulto Jovem
12.
Int J Pediatr Otorhinolaryngol ; 70(5): 785-98, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16246433

RESUMO

OBJECTIVES: (1) To adopt the nasometry for the Hungarian language and to obtain normative nasalance scores. (2) To compare our results with the data of other languages and to evaluate the correlation between nasalance scores and perceptual ratings of nasality. (3) To use the nasometry in various fields of the otolaryngological, phoniatric, and logopedic diagnostics, therapy and documentation. METHODS: (1) To determine the normative nasalance scores regarding the Hungarian language, we included 30 children aged 5-7 years and 45 adults in the 20-25 years age group. In the latter group 15 subjects were speech therapists and 30 phonetically untrained people-15 males and 15 females. STUDY DESIGN: phonation of isolated vowels, articulation of spirants, cyclical repetition of affricates, pronunciation of various (oral, nasal, mixed type) sentences and evaluation of the nasalance score in continuous speech. (2) Thirty-six persons (12 speech pathologists, 12 logopedic students, 12 phonetically uneducated individuals) evaluated the children's physiological and nasal speech recordings with a 3-point scale. (3) Two hundred and forty-eight children of kindergarten age were examined, 20 infants and 6 adult singers in the following fields: evaluation of hypernasality due to cleft palate or velopharyngeal insufficiency (VPI), and of the success of the therapy; examination of hyponasality in cases of enlarged adenoid and allergic rhinitis; evaluation of the speech of hard-of-hearing people; differentiation between nasal sigmatism and hyperrhinophony; testing of the resonance in professional singers; examination of infant cry; application of nasometry in the therapy. RESULTS: The mean value of the nasalance score using the oral sentence: "Zsuzsi kutyája ugat" is 11-13%, in the nasal sentence ("A majom banánt enne") 56%, while that of the mixed sentence representing the Hungarian language ("Jó napot kívánok!") falls in the 30-40% range. The resonance grows with aging and there is no significant difference between genders. The nasalance score is greater with phonetically trained people. Our data correlate with the values of other languages. The correlation is significant between the nasalance scores and perceived nasality (r=0.901). Practical results: Values above 40% in cases of VPI using mixed sentences may support the indication of velopharyngoplasty, together with the subjective evaluation of nasality and other tests. In cases with rhinitis and adenoid vegetation the nasalance score remains below 20%. The nasality value is increased in sensorineural hearing loss, and is decreased in cases with conducting hearing impairment. In nasal sigmatism not the vowels' but the nasality of consonants grow. The difference between the nasalance score of the cry in clefted and non-cleft infants is significant (26% versus 36%): this observation could give possibility in the future to screen babies with congenital hearing problems or hidden VPI. Alterations in nasalance can be documented with nasometry in professional singers when they increase the nasal resonance to grow the power capacity of their voice. The nasometry procedure is a significant help also in speech therapy through the real time visual and auditive control. CONCLUSIONS: The otolaryngological, phoniatric and logopedic diagnostics and therapy is significantly widened with nasometry which is a quick, non-invasive and objective procedure, measuring the nasal resonance of the speech.


Assuntos
Idioma , Cavidade Nasal/fisiologia , Fonação/fisiologia , Medida da Produção da Fala , Fala/fisiologia , Adulto , Envelhecimento/fisiologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Espectrografia do Som
13.
Clin Infect Dis ; 41(11): 1621-7, 2005 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-16267735

RESUMO

BACKGROUND: To describe trends in bacterial diarrhea among human immunodeficiency virus (HIV)-infected persons during 1992-2002, we examined data from a longitudinal record review study of persons with HIV infection who were receiving medical care in >100 medical facilities in 9 major United States cities. METHODS: An analysis was performed using data from 44,778 persons who were followed up for a mean of 2.6 years. We calculated incidence rates and rate ratios for bacterial diarrhea, by stage of HIV disease, and determined odds ratios (ORs) to compare bacterial diarrhea diagnosis in 2002 versus 1992. RESULTS: The mean annual incidence of bacterial diarrhea was 7.2 cases per 1000 person-years. The incidence of Clostridium difficile-associated diarrhea, the most common bacterial cause of diarrhea, was 4.1 cases per 1000 person-years. Compared with persons without AIDS, persons with AIDS were more likely to have bacterial diarrhea (incidence rate ratio, 1.3-9.9, varying by clinical versus immunologic AIDS and type of bacterial diarrhea). Between 1992 and 2002, the overall rate of bacterial diarrhea in persons with clinical AIDS decreased (OR, 0.4; 95% confidence interval, 0.2-0.6). During the same period, bacterial diarrhea rates among other persons in the analysis did not significantly change. CONCLUSIONS: C. difficile is the most common recognized cause of bacterial diarrhea among persons infected with HIV. The risk for bacterial diarrhea increases with increased severity of HIV disease. Health care professionals should be aware that patients with AIDS are at increased risk for bacterial diarrhea, and they should reinforce recommendations for decreasing the chances of acquiring bacterial diarrhea.


Assuntos
Infecções Bacterianas/etiologia , Diarreia/epidemiologia , Diarreia/microbiologia , Infecções por HIV/complicações , Adolescente , Adulto , Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/microbiologia , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Humanos , Incidência , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Razão de Chances , Fatores de Tempo , Estados Unidos/epidemiologia
14.
J Pharm Biomed Anal ; 59: 190-3, 2012 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-22075373

RESUMO

The thermal decomposition kinetics and shelf life of vitamin C in nitrogen or air were studied by using thermogravimetric analysis (TGA) and evolved-gas analysis-lithium-ion attachment mass spectrometry (EGA-Li⁺IAMS). Arrhenius parameters obtained via TGA were reported for thermal decomposition. For vitamin C in a nitrogen atmosphere, the activation energy (E(a)) was 25.1 kcal/mol and the pre-exponential factor (A) was 2.5 × 10¹¹ min⁻¹. The kinetic parameters estimated via TGA agreed with values estimated from a pyrogram when the weight loss observed by TGA was shown to be due to gas evolution as a result of decomposition of the compound. Thermal stability was expressed by calculating the time for 10% of the vitamin C to decompose at 25 °C (t(90%,25 °C)). The t(90%,25 °C) for vitamin C obtained via TGA or EGA-Li⁺IAMS was higher in nitrogen (2.0 and 2.0 years, respectively) than in air (1.3 and 1.6 years, respectively). This indicates that the type of atmosphere influences vitamin C stability.


Assuntos
Ácido Ascórbico/análise , Temperatura Alta , Espectrometria de Massas/métodos , Ácido Ascórbico/normas , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Cinética , Termogravimetria
15.
Food Chem ; 129(2): 546-550, 2011 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30634265

RESUMO

Evolved gas analysis-ion attachment mass spectrometry (EGA-IAMS) was utilised to study the real-time non-isothermal decomposition of vitamin C. Dehydro-l-ascorbic acid, which has until this study been undetectable from the solid phase degradation of vitamin C, was observed as a decomposition product. While it is an important compound because it possesses some biological activity, dehydro-l-ascorbic acid is difficult to measure due to its chemical instability. In the present study using EGA-IAMS, we were able to detect dehydro-l-ascorbic acid from the thermal degradation of vitamin C. Our EGA-IAMS results obtained from the thermal decomposition of vitamin C were compared with a previous study employing pyrolysis-gas chromatography-mass spectrometry (Pyr-GC-MS). The observed quantitative and qualitative differences of the pyrolysis products obtained by the two techniques (EGA-IAMS vs. Pyr-GC-MS) are in part due to the difference in transportation time of the products out of the pyrolysis chamber.

16.
Rapid Commun Mass Spectrom ; 22(10): 1510-8, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18425798

RESUMO

The 14 and 70 eV electron ionization mass spectra of five sets (R1 = Me, Et, i-Pr, t-Bu and Ph) of seven 2-aryl-4-R1-substituted (Ar = C6H4X; X = p-NO2, m-Br, p-Cl, H, p-Me, p-OMe and p-NMe2) (1-5) and of seven 2-aryl-5-phenyl-substituted 1,3-oxazolidines (6; for Ar, see above) were recorded to study their ring-chain equilibria in the gas phase. These equilibria were also studied by 1H NMR spectroscopy in CDCl3 for compounds 5 and 6. A few 2,4- and 2,5-dimethyl-2-aryl derivatives (7, 8: Ar = C6H4X; X = m-Br, H and p-OMe) were studied both in CDCl3 and in the gas phase. The main characteristics of the ring-chain equilibria expressed by the variable SigmaRA% of the ring and of the chain form proved to be a strong dependence on the nature of the substituents on C-2 and C-4. The results in the gas phase are compared with those in CDCl3.

17.
Arch Ophthalmol ; 126(6): 849-56, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18541852

RESUMO

OBJECTIVE: To assess the impact of vision loss severity on costs and health outcomes among Medicare beneficiaries with glaucoma. METHODS: A retrospective cohort analysis was conducted using Medicare claims. Patients were stratified into 4 categories: no vision loss, moderate vision loss, severe vision loss, and blindness. Outcomes of interest were mean annual medical costs by category, component costs, and frequency of depression, falls and/or accidents, injury, femur fracture, and nursing home placement. RESULTS: Multivariate regression analysis showed that patients with any degree of vision loss had 46.7% higher total costs compared with patients without vision loss. Mean total and component costs increased with onset and severity ($8157 for no vision loss to $18,670 for blindness). Patients with vision loss were significantly more likely to be placed in a nursing home (odds ratio = 2.18; 95% confidence interval, 2.06-2.31), develop depression (odds ratio = 1.63; 95% confidence interval, 1.54-1.73), fracture a femur (odds ratio = 1.67; 95% confidence interval, 1.53-2.83), or experience a fall or accident (odds ratio = 1.59; 95% confidence interval, 1.50-1.68) vs patients without vision loss. CONCLUSIONS: Vision loss in glaucoma is costly, and costs increase with severity. There is significantly increased risk of nursing home admission, depression, falls and/or accidents, injury, or femur fracture with vision loss compared with no vision loss.


Assuntos
Glaucoma/complicações , Glaucoma/economia , Custos de Cuidados de Saúde , Medicare , Transtornos da Visão/economia , Transtornos da Visão/fisiopatologia , Acidentes por Quedas , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Depressão/etiologia , Feminino , Fraturas do Fêmur/etiologia , Humanos , Institucionalização , Masculino , Casas de Saúde , Estudos Retrospectivos , Índice de Gravidade de Doença , Estados Unidos , Transtornos da Visão/complicações , Transtornos da Visão/etiologia
18.
Rapid Commun Mass Spectrom ; 21(22): 3701-10, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17957811

RESUMO

The electron ionization mass spectra of five series of seven 2-aryl,4-R-substituted (R = Me, Et, i-Pr, t-Bu or Ph) 3,4,5,6-tetrahydro-2H-1,3-oxazines were recorded at 14 and 70 eV in order to study the ring-chain tautomeric equilibria in the gas phase. Certain fragment ions were associated with the ring or with the open-chain forms of the compounds. As in chloroform solution, the electron-withdrawing effect of the aryl substituent (p-NO(2), m-Br, p-Cl, H, p-Me, p-OMe and p-NMe(2)) shifts the equilibrium towards the ring form. The correlation of ring-chain equilibria (log K = [ring]/[chain]) with the Hammett sigma+ constants of the aryl substituents was in general good or satisfactory although in some cases the p-NMe(2) did not fit these correlations.


Assuntos
Oxazinas/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Gases/química , Estereoisomerismo
19.
J Infect Dis ; 196(3): 339-46, 2007 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-17597447

RESUMO

BACKGROUND: Although annual influenza vaccination of human immunodeficiency virus (HIV)-infected patients has been recommended in the United States since the early 1990s, vaccine coverage in this population is reported to be low. The objectives of the present study were to assess trends in influenza vaccination coverage in HIV-infected patients and to determine predictors of influenza vaccination. METHODS: We analyzed data from the medical records of 51,021 HIV-infected patients from 10 US cities observed in a longitudinal cohort study between 1990 and 2002. Using multivariate logistic regression, we determined predictors of influenza vaccination for both the pre-highly active antiretroviral therapy (HAART) and HAART eras. RESULTS: Vaccination coverage increased from 28.5% in the 1990 to 41.6% in the 2002 influenza season. Vaccine coverage increased with increasing age and frequency of medical visits. In the HAART era, persons prescribed antiretroviral therapy were more likely and those with higher viral loads and lower CD4 T cell counts were less likely to have received influenza vaccine. CONCLUSIONS: Although influenza vaccination coverage in this population has increased in recent years, it is well below the Healthy People 2010 target of 60%. Efforts should be undertaken to increase influenza vaccination in HIV-infected persons.


Assuntos
Infecções por HIV/complicações , Infecções por HIV/imunologia , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/imunologia , Influenza Humana/complicações , Influenza Humana/prevenção & controle , Adolescente , Adulto , Terapia Antirretroviral de Alta Atividade , Feminino , Infecções por HIV/epidemiologia , Humanos , Influenza Humana/imunologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores de Tempo , Estados Unidos/epidemiologia
20.
Curr Med Res Opin ; 23(10): 2453-60, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17727740

RESUMO

OBJECTIVE: To review the evidence evaluating the efficacy of vardenafil in subgroups of hypertensive patients with erectile dysfunction (ED). METHODS: Meta-analysis of randomized, double-blinded, placebo-controlled, flexible-dose vardenafil clinical trials that were >or=12 weeks in duration evaluated men with a >or=6-month history of ED and required a >or=50% failure rate in baseline sexual attempts. The primary endpoints analyzed were the erectile function domain of the International Index of Erectile Function questionnaire (IIEF-EF) and Sexual Encounter Profile questions 2 (SEP2) and 3 (SEP3). RESULTS: Eight clinical trials were included (n = 2427 patients) consisting of 839 patients (35%) with a self-reported diagnosis of hypertension (HTN): 498 in the vardenafil and 341 in the placebo groups. Vardenafil's efficacy was evidenced by an average increase of 8.9 points in the IIEF-EF (95% CI: 7.4, 10.5) at week 12 compared to placebo, with individual trial values ranging from 16.4 to 26.1 and 11.3 to 17.8 for the vardenafil and placebo groups, respectively. Vardenafil also increased success rates for the ability to obtain erections (SEP2) by 32.4% (95% CI: 27.4%, 37.5%) over a 12-week timeframe compared to placebo, with individual trial values ranging from 57.2% to 92.2% for vardenafil and 32.0% to 66.9% for placebo. Similarly, success rates for the ability to maintain erections (SEP3) improved 38.0% (95% CI: 29.5%, 46.6%) compared to placebo, with individual trial values ranging from 41.7% to 88.2% for vardenafil and 20.5% to 51.4% for placebo. Vardenafil was equally efficacious in improving IIEF-EF, SEP2, and SEP3 in those with and without self-reported HTN. CONCLUSION: This meta-analysis demonstrated that vardenafil was significantly more efficacious than placebo for the treatment of ED in patients with comorbid HTN and offered similar treatment benefits in patients without HTN.


Assuntos
Disfunção Erétil/tratamento farmacológico , Hipertensão/complicações , Imidazóis/uso terapêutico , Inibidores de Fosfodiesterase/uso terapêutico , Piperazinas/uso terapêutico , Adulto , Idoso , Método Duplo-Cego , Disfunção Erétil/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Placebos , Ensaios Clínicos Controlados Aleatórios como Assunto , Sulfonas/uso terapêutico , Resultado do Tratamento , Triazinas/uso terapêutico , Dicloridrato de Vardenafila
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