RESUMO
Cysteine S-H bonds have a spectroscopically convenient stretching frequency of â¼2550 cm-1. However, their cross section is low, and the band can be strongly broadened in heterogeneous environments, making detection very challenging. With two-dimensional infrared (2D-IR) setups achieving ever higher sensitivities in recent years, systematic use of the weak cysteine sulfhydryls (Cys-SHs) absorption band is now within reach, even at low millimolar protein concentrations. Here, we demonstrate the capabilities of Cys-SH as an intrinsic 2D-IR label in pyruvate oxidase from E. coli, an enzyme with ten cysteines in its native sequence. 1D-IR measurements on the wild-type and individual cysteine knock-out variants show that two such residues have especially narrow SH signatures, caused by their intrahelical hydrogen bonding. 2D-IR analysis of these bands reveals an extraordinarily high anharmonicity (â¼110 cm-1) and a long vibrational lifetime (â¼4 ps). This allows monitoring spectral diffusion via center line slope analysis for up to 10 ps-separately for both the ground and excited states. The unique spectroscopic features and its ease of introduction make Cys-SH a useful IR spectroscopic label.
Assuntos
Cisteína , Escherichia coli , Cisteína/química , Ligação de Hidrogênio , Piruvato Oxidase , Espectrofotometria Infravermelho/métodosRESUMO
Water-soluble chlorophyll (chlorophyllin) was used in a phototoxic reaction against a number of fish ectoparasites such as Ichtyobodo, Dactylogyrus, Trichodina, and Argulus. Chlorophyllin is applied to the water at concentrations of several micrograms per milliliter for a predefined incubation time, and afterwards, the parasites are exposed to simulated solar radiation. Application in the dark caused only little damage to the parasites; likewise, light exposure without the addition of the photosensitizer was ineffective. In Ichthyobodo, 2 µg/mL proved sufficient with subsequent simulated solar radiation to almost quantitatively kill the parasites, while in Dactylogyrus, a concentration of about 6 µg/mL was necessary. The LD50 value for this parasite was 1.02 µg/mL. Trichodina could be almost completely eliminated at 2 µg/mL. Only in the parasitic crustacean Argulus, no killing could be achieved by a photodynamic reaction using chlorophyllin. Chlorophyllin is non-toxic, biodegradable, and can be produced at low cost. Therefore, we propose that chlorophyllin (or other photodynamic substances) are a possible effective countermeasure against several ectoparasites in ponds and aquaculture since chemical remedies are either forbidden and/or ineffective.
Assuntos
Antiparasitários/uso terapêutico , Clorofilídeos/uso terapêutico , Doenças dos Peixes/parasitologia , Doenças dos Peixes/terapia , Parasitos/efeitos dos fármacos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/uso terapêutico , Animais , Aquicultura , Arguloida/efeitos dos fármacos , Clorofila , Cilióforos/efeitos dos fármacos , Peixes/parasitologia , Platelmintos/efeitos dos fármacos , Spiroplasma/efeitos dos fármacos , ÁguaRESUMO
Water-soluble chlorophyll (chlorophyllin) exerts pronounced photodynamic activity on fish parasites. In order to determine its potential as a remedy against ectoparasites in fish carps were incubated in water with defined concentrations of chlorophyllin. The main focus of the experiments was on the ciliate Ichthyophthirius multifiliis (Fouquet) which is responsible for considerable losses in livestock in aquaculture. As malachite green, which in the past efficiently cured infected fishes, is banned because of its possible carcinogenicity; no effective remedy is presently available in aquaculture to treat ichthyophthiriasis. Using chlorophyllin, the number of trophonts was significantly reduced (more than 50 %) after 3 h incubation of infested fish at 2 and 4 mg/L and subsequent irradiation with simulated solar radiation. The lack of reinfection after light treatment indicates that also the remaining parasites have lost their multiplication capacity. In the controls (no chlorophyllin and no light, light but no chlorophyllin, or chlorophyllin but no light), no reduction of the I. multifiliis infection was observed. We propose that chlorophyllin (or other photodynamic substances) is a possible effective countermeasure against I. multifiliis and other ectoparasites in aquaculture.
Assuntos
Anti-Infecciosos Locais/uso terapêutico , Carpas , Clorofilídeos/uso terapêutico , Infecções por Cilióforos/veterinária , Cilióforos/classificação , Animais , Aquicultura , Cilióforos/efeitos dos fármacos , Infecções por Cilióforos/tratamento farmacológico , Infecções por Cilióforos/parasitologia , Doenças dos Peixes/parasitologiaRESUMO
The spin polarizabilities of the nucleon describe how the spin of the nucleon responds to an incident polarized photon. The most model-independent way to extract the nucleon spin polarizabilities is through polarized Compton scattering. Double-polarized Compton scattering asymmetries on the proton were measured in the Δ(1232) region using circularly polarized incident photons and a transversely polarized proton target at the Mainz Microtron. Fits to asymmetry data were performed using a dispersion model calculation and a baryon chiral perturbation theory calculation, and a separation of all four proton spin polarizabilities in the multipole basis was achieved. The analysis based on a dispersion model calculation yields γ(E1E1)=-3.5±1.2, γ(M1M1)=3.16±0.85, γ(E1M2)=-0.7±1.2, and γ(M1E2)=1.99±0.29, in units of 10(-4) fm(4).
RESUMO
BACKGROUND: Detection of delayed cerebral ischemia (DCI) in high-grade subarachnoid haemorrhage (SAH) is an unsolved issue. Conventional near-infrared spectroscopy (NIRS) with optodes applied over the skin is controversial because the NIRS signal is contaminated by extracerebral tissue. The objective is to quantify and subtract the contribution from extracerebral tissue from the signal by using measurements in parallel with a NIRS brain tissue probe and conventional NIRS. METHODS: In a patient with high-grade SAH, two approaches for NIRS were applied. First, a conventional brain tissue probe for intracranial pressure (ICP) monitoring, supplied by optical fibres, was placed into the brain tissue 2 cm deep from the dura. Second, for conventional NIRS, a plaster-based patch carrying optodes (one emitter, two detectors) was attached to the skin. Central venous injections of 0.3 mg/kg body weight (bw) indocyanine green (ICG) were performed. ICG dye dilution curves obtained with the probe and patch were collected simultaneously and analysed for blood flow values. RESULTS: Twelve measurements in parallel with the probe and patch were performed. Mean cerebral blood flow (CBF) for the probe was higher (24.8 ± 9.1 ml/100 g/min) compared with the values obtained with the patch (for detector 1, extra-cerebral blood flow [ECBF] mean 5.1 ± 1.8 ml/100 g/min; p = 0.002; for detector 2, 6.6 ± 2.1 ml/100 g/min; p = 0.002). CBF values obtained with the probe correlated with blood flow values obtained with the patch (for CBF vs. ECBF detector 1, r = 0.72 [p = 0.008]; ECBF detector 2, r = 0.79 [p = 0.002]). CONCLUSIONS: Blood flow values obtained with conventional NIRS correlated significantly with absolute CBF values obtained directly within the brain tissue. Simultaneous measurements with the NeMo Probe and NeMo Patch allow quantification and subtraction of the contribution from extracerebral tissues from the signal obtained with conventional NIRS.
Assuntos
Isquemia Encefálica/diagnóstico , Circulação Cerebrovascular , Monitorização Fisiológica/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Hemorragia Subaracnóidea/complicações , Algoritmos , Tempo de Circulação Sanguínea/instrumentação , Tempo de Circulação Sanguínea/métodos , Isquemia Encefálica/etiologia , Isquemia Encefálica/metabolismo , Corantes , Simulação por Computador , Humanos , Verde de Indocianina , Pressão Intracraniana , Monitorização Fisiológica/instrumentação , Método de Monte Carlo , Processamento de Sinais Assistido por Computador , Espectroscopia de Luz Próxima ao Infravermelho/instrumentação , Fatores de TempoRESUMO
We present new data for the transverse target asymmetry T and the very first data for the beam-target asymmetry F in the γ[over â]p[over â]âηp reaction up to a center-of-mass energy of W=1.9 GeV. The data were obtained with the Crystal-Ball/TAPS detector setup at the Glasgow tagged photon facility of the Mainz Microtron MAMI. All existing model predictions fail to reproduce the new data indicating a significant impact on our understanding of the underlying dynamics of η meson photoproduction. The peculiar nodal structure observed in existing T data close to threshold is not confirmed.
RESUMO
A precision measurement of the differential cross sections dσ/dΩ and the linearly polarized photon asymmetry Σ≡(dσâ¥-dσâ¥)/(dσâ¥+dσâ¥) for the γpâπ0p reaction in the near-threshold region has been performed with a tagged photon beam and almost 4π detector at the Mainz Microtron. The Glasgow-Mainz photon tagging facility along with the Crystal Ball/TAPS multiphoton detector system and a cryogenic liquid hydrogen target were used. These data allowed for a precise determination of the energy dependence of the real parts of the S- and all three P-wave amplitudes for the first time and provide the most stringent test to date of the predictions of chiral perturbation theory and its energy region of agreement with experiment.
Assuntos
Pinos Ortopédicos , Fixação Intramedular de Fraturas/instrumentação , Fixação Intramedular de Fraturas/métodos , Fraturas do Úmero/diagnóstico por imagem , Fraturas do Úmero/cirurgia , Fraturas do Rádio/diagnóstico por imagem , Fraturas do Rádio/cirurgia , Criança , Traumatismos do Antebraço/diagnóstico por imagem , Traumatismos do Antebraço/cirurgia , Humanos , Guias de Prática Clínica como Assunto , Padrões de Prática Médica , RadiografiaRESUMO
Fractures of the forearm in children are quite frequent injuries, treated in emergency rooms. Most of them occur during leisure or sport activities. Most cases are monotraumatic. The diagnosis can be made by a conventional x-ray examination of the forearm in two planes. It is possible to differentiate between stable fractures (greenstick fractures) and unstable (dislocated) fractures. The first-line therapy for stable fractures or fractures which can be reduced anatomically correctly, is the conservative procedure using a long arm cast. Axial dislocation up to 20 degrees (age <5 years) or up to 10 degrees (age >5 years) can be accepted. Special cases, such as Monteggia or Galeazzi fractures, must be considered. Unstable fractures have to be reduced during surgical stand-by. The state of the art in surgical therapy is intramedullary nailing with titanium elastic nails. Open fractures and fractures with severe soft tissue injuries can be treated with external fixation. Osteosynthesis with plates should only be used for special indications. By following therapeutic principles, a successful outcome can be achieved and later complications are rare.
Assuntos
Pinos Ortopédicos , Placas Ósseas , Fixação Interna de Fraturas/instrumentação , Fraturas do Úmero/diagnóstico por imagem , Fraturas do Úmero/cirurgia , Fraturas do Rádio/diagnóstico por imagem , Fraturas do Rádio/cirurgia , Criança , Traumatismos do Antebraço/diagnóstico por imagem , Traumatismos do Antebraço/cirurgia , Fixação Interna de Fraturas/métodos , Humanos , Guias de Prática Clínica como Assunto , Padrões de Prática Médica , RadiografiaRESUMO
OBJECTIVE: To determine the prevalence of testing for hepatitis B virus (HBV) infection in the clinical management of primary liver cancer (hepatocellular carcinoma). METHODS: The authors reviewed the records of 78 patients treated for hepatocellular carcinoma in hospitals in the Puget Sound area in 1988 and early 1989 and reviewed all 1990 U.S. death certificates on which primary liver cancer was listed. RESULTS: The records of 50 (64%) of 78 hepatocellular carcinoma patients contained no evidence that the patient's hepatitis B surface antigen (HBsAg) status had been determined. In addition, of 4353 people who died in 1990 for whom the diagnosis of primary liver cancer was listed on the death certificate, HBV infection was also listed for only 136 (3%), much less than expected based on case series. CONCLUSIONS: Many patients with hepatocellular carcinoma are not tested for HBV infection, suggesting that their close contacts are also not evaluated for HBV infection and the need for vaccination. Hepatitis B vaccination of close personal contacts of HBV-infected hepatocellular carcinoma patients is an important strategy for preventing HBV transmission.
Assuntos
Carcinoma Hepatocelular/virologia , Hepatite B/complicações , Hepatite B/diagnóstico , Controle de Infecções/métodos , Neoplasias Hepáticas/virologia , Atestado de Óbito , Hepatite B/prevenção & controle , Hepatite B/transmissão , Antígenos de Superfície da Hepatite B/sangue , Humanos , Prevalência , Estudos Retrospectivos , Programa de SEER , WashingtonRESUMO
120 carp (Cyprinus carpio L.) with an average initial weight of 516 g, were kept in 20 tanks at a water temperature of 23 degrees C and given five different commercially practical diets to an end weight of approximately 1000 g. Four of the diets consisted of more than 50% of the traditional sole feeds wheat (W), rye (R), maize (M), or lupin seed (L), mixed with other ingredients to give diets with similar concentration of energy and crude protein. The fifth diet consisted exclusively of deep frozen zooplankton (Z). The fish were given a daily feed amount of 1.8% of bodyweight. The bodyweights of the carp on the cereal diets or the lupin seed diet were similar at the end of the experiment, after 105 days, (W) 995 g, (R) 916 g, (M) 979 g, (L) 979 g, but were significantly lower on diet (Z) at 659 g. Average OM digestibility coefficients for the diets were 77-79% for the cereal-rich diets, 68% for (L), and 75% for (Z). The contents of skinless fillet (average 38.7%), viscera (average 13.2%) and residual carcass (average 48.2%) were similar for the diets with cereals or lupin seed, while fish on diet (Z) had significantly lower fillet proportion (33.6%), coupled with an increase in residual carcass (53.0%). The chemical composition of the fillet, viscera and the residual carcass was also affected. Fish on diet (M) had the highest fat content in the whole body (14.5% of the FM), followed by those on diets (W) and (R) at 13.3% and 12.9%, while fish on diets (L) and (Z) had significantly lower fat contents at 10.7% and 8.2%. Protein contents in the whole body (% of FM) were for diets (L) 16.7%, (W) 16.4% (R) 16.3%, (M) 16.2%, and (Z) 15.5%.
Assuntos
Carpas/crescimento & desenvolvimento , Dieta/veterinária , Grão Comestível/metabolismo , Fabaceae/metabolismo , Produtos Pesqueiros/normas , Plantas Medicinais , Zooplâncton/metabolismo , Animais , Composição Corporal/fisiologia , Peso Corporal/fisiologia , Carpas/metabolismo , Carpas/fisiologia , Dieta/normas , Proteínas Alimentares/farmacologia , Proteínas Alimentares/normas , Fatores de Tempo , Aumento de Peso/fisiologiaRESUMO
Despite great improvements in recent decades, the health status of American Indians continues to lag behind that of other Americans. Continued health improvement will depend largely on changes in individual behavior. Until recently, however, few data existed on health risk behaviors among American Indians. We conducted personal interviews among the adult population of an Indian Health Service Unit in Washington State to estimate the prevalence of some health risk behaviors. This analysis focuses on three of the many topics covered in the survey: tobacco use, alcohol consumption, and weight. Cigarette smoking was more prevalent among both men and women than it was in the general population in the same area with 43% of men and 54% of women among the American Indians interviewed reported that they currently smoked. However, they tended to smoke much less heavily than smokers in the general population. Smokeless tobacco use was concentrated among young men, with the overall prevalence similar to that found in the general population. Acute heavy drinking was found to be common with 40% of men and 33% of women reporting this behavior for the previous month. The prevalence of substantial overweight was 45% among men and 43% among women, considerably higher than in the general population. Tribal leaders and the Indian Health Service are using the findings to design disease prevention and health promotion activities. In addition to providing valuable information about the surveyed populations, the survey served as a pilot for similar studies of other American Indian groups.
Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Comportamentos Relacionados com a Saúde , Indígenas Norte-Americanos , Obesidade/epidemiologia , Fumar/epidemiologia , Adolescente , Adulto , Fatores Etários , Doença Crônica/epidemiologia , Escolaridade , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Plantas Tóxicas , Prevalência , Fatores de Risco , Tabaco sem Fumaça , Washington/epidemiologiaRESUMO
THE ASSESSMENT PROTOCOL for EXCELLENCE in PUBLIC HEALTH process was carried out in the state of Washington to assess local health department capacity and to identify their self-perceived strengths and weaknesses. Staff from 24 of the 32 local health departments in Washington completed organizational capacity assessments. Fifty percent or more of the health departments identified the following eight indicators as strengths: legal authority, public policy and implementation, budget development, financial reporting and administration, audit, financial documentation, organization and structure of program management, and policy board procedures. Seven indicators were identified as weaknesses by 50% or more of the respondents: legal counsel, mission and role, data collection and analysis, planning and development, evaluation and assurance of community health assessment, community health assessment and planning, and community health policy. The results of the assessment highlight the traditional organizational and service delivery strengths of the local health departments and point out weaknesses in their ability to assess community health and to develop communitywide health policy.
Assuntos
Serviços de Saúde Comunitária/normas , Saúde Pública , Serviços de Saúde Comunitária/organização & administração , Atenção à Saúde/normas , Administração Financeira , Humanos , Formulação de Políticas , Garantia da Qualidade dos Cuidados de Saúde , WashingtonRESUMO
To assess whether trained nursing personnel could provide IUD services as safely and effectively as physicians in Brazil, an experimental study was conducted at the main clinic of the Center for Research on Integrated Maternal and Child Care in Rio de Janeiro. From November 1984 through April 1986, a total of 1,711 women who requested IUD insertion at the clinic were randomly assigned to have a Copper-T 200 IUD inserted by one of the clinic's 11 physicians or 13 nurses. All of the physicians and nursing staff members who provided these services had taken the Center's standard clinical family planning training course. Of 860 insertions attempted by the physicians and nurses, 1.3% and 3.3%, respectively, were unsuccessful. Statistically, this difference was very significant (P < 0.01). Also, mainly because the cervix was small and undilated, nulliparous women had a relatively high insertion failure rate of 8.0%, as compared to 1.5% for primiparas and 1.0% for multiparas. The overall rate of complications at insertion was 1.8%, these complications including diaphoresis, vomiting, syncope, cervical laceration, and one case of perforation of the uterus; no significant difference was found between the complication rates for insertions performed by physicians as compared to nurses. However, 9.0% of the study subjects reported severe pain during IUD insertion, with significantly higher percentages reporting pain if the IUD was inserted by a physician, or if the subject was nulliparous, had preinsertion symptoms, or had a history of pelvic inflammatory disease (PID) or sexually transmitted disease (STD). It was also found that the nurses had a dramatically high insertion failure rate (11.6%) with nulliparous subjects, while the physicians' failure rate with such subjects was a significantly lower 3.4%. No significant difference was found in the groups served by nurses and physicians with regard to postinsertion complaints or termination of use within 12 months of insertion. These findings suggest that future training, besides preparing nursing personnel in IUD insertion, should emphasize preparation in taking the client's medical history and diagnosing existing medical symptoms that could be associated with IUD insertion complications. In addition, if a nulliparous woman requests an insertion, it should be performed by a physician or more experienced nursing staff member with close medical supervision. Because of high rates of reported pain at insertion, such women, as well as those with medical symptoms associated IUD insertion complications and those with a history of PID or STD, should be considered candidates for extra care and counseling.(ABSTRACT TRUNCATED AT 400 WORDS)
PIP: In the mid-1980s in Brazil, health workers randomly assigned 1711 women aged 15-48 requesting IUD insertion at the Center for Research on Integrated Maternal and Child Care clinic in Rio de Janeiro to have the Copper-T 200 IUD inserted by a physician or by a nurse. The study aimed to determine whether trained nurses could perform as safe and effective IUD insertions as physicians. Insertion failure was more common when performed by nurses than physicians (3.3% vs. 1.3%; p = 0.005). Severe pain at insertion was more common during physician insertions than nurse insertions (10.8% vs. 7.1%; p = 0.008) and in women who had menstrual bleeding, bleeding, dysmenorrhea, or pelvic pain than in women lacking these preinsertion symptoms (14.2% vs. 7.8%; p 0.001). History of pelvic inflammatory disease (PID) or a sexually transmitted disease (STD) increased the likelihood of severe pain at insertion (14.5% vs. 8.5%; p = 0.022). Nulliparous women were more likely to experience insertion failure than parous women regardless of provider, especially for nurse insertions (11.6% vs. 1.6%; p 0.01). The higher failure rate among nurses was probably due to a higher proportion of nulliparous women in the nurse insertion group (17.2% vs. 13.6%; p 0.05). The overall IUD use-effectiveness rate at 12 months was 98.8% (98.6% for physicians and 99% for nurses). The cumulative IUD continuation rate at 12 months was slightly better for nurse insertions than for physician insertions (75.2% vs. 74.4%). There were no significant differences between termination rates regardless of reason (pregnancy, expulsion, or removal) between physicians and nurses. The increases in complaint rates between preinsertion and postinsertion were the same for both physicians and nurses (25.8% and 25.1%, respectively). These results indicate the need to emphasize taking the client's medical history and diagnosing existing medical symptoms that are possibly linked to IUD insertion complications. Physicians or more experienced nurses should insert an IUD in nulliparous women. More counseling and care are needed for women with IUD insertion complications and those with a history of PID or STD.
Assuntos
Competência Clínica , Dispositivos Intrauterinos de Cobre , Centros de Saúde Materno-Infantil/organização & administração , Recursos Humanos de Enfermagem , Adolescente , Adulto , Brasil , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Feminino , Humanos , Expulsão de Dispositivo Intrauterino , Dispositivos Intrauterinos de Cobre/efeitos adversos , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
To explore sexually transmitted diseases and sexual behavior as risk factors for cervical cancer, we analyzed data from a population-based case-control study of breast and cervical cancer in Costa Rica. Data from 415 cases of cervical carcinoma in situ, 149 cases of invasive cervical cancer, and 764 controls were included in the analysis. Multivariate analysis showed that lifetime number of sex partners, first intercourse before age 15 years, number of livebirths, herpes simplex virus type 2 seropositivity, and serologic evidence of previous chlamydial infection were predictors of carcinoma in situ. Serologic evidence of previous syphilis was not associated with carcinoma in situ. Predictors for invasive cervical cancer included lifetime number of sex partners, first intercourse before age 15 years, number of livebirths, serologic evidence of previous syphilis, herpes simplex type 2 infection, and chlamydial infection. Cigarette smoking, socioeconomic status, self-reported history of sexually transmitted diseases, and douching were not associated with either carcinoma in situ or invasive cervical cancer.
Assuntos
Comportamento Sexual , Infecções Sexualmente Transmissíveis/complicações , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/etiologia , Adulto , Distribuição por Idade , Análise de Variância , Carcinoma in Situ/epidemiologia , Carcinoma in Situ/etiologia , Estudos de Casos e Controles , Costa Rica/epidemiologia , Feminino , Humanos , Incidência , Modelos Logísticos , Pessoa de Meia-Idade , Análise Multivariada , Fatores de Risco , Infecções Sexualmente Transmissíveis/epidemiologia , Fumar , Fatores SocioeconômicosRESUMO
An outbreak investigation practicum option for graduate students at the University of Washington School of Public Health and Community Medicine has three goals of education, scientific investigation, and exposure to operations of public health agencies. Over a six-year period, 48 students performed 40 outbreak investigations in collaboration with adjunct faculty based in local public health agencies. An outbreak investigation practicum at Yale University had similar goals, but the rapid-response team approach there generally involved one regular faculty member and a team of graduate students. In either program, the level of faculty involvement necessary for outbreak investigations is sustainable only if the faculty value public health practice as part of the school's mission. Since public health students need to acquire many practical skills, a short outbreak investigation practicum experience should not be viewed in isolation, but rather should be one of a variety of practicum offerings available to students at schools of public health.
Assuntos
Surtos de Doenças , Prática de Saúde Pública , Saúde Pública/educação , Currículo , Humanos , Faculdades de Saúde Pública/organização & administraçãoRESUMO
Writing journal articles quite often becomes a low priority for public health professionals in a busy agency setting. Despite the obstacles, an agency setting offers many opportunities to enhance public health knowledge. Opportunities for publication in an agency setting are reviewed, with examples of citations from the published literature.