Water chemistry and its effects on the physiology and survival of Atlantic salmon Salmo salar smolts.

The physiological effects of episodic pH fluctuations on Atlantic salmon Salmo salar smolts in eastern Maine, U.S.A., were investigated. During this study, S. salar smolts were exposed to ambient stream-water chemistry conditions at nine sites in four catchments for 3 and 6 day intervals during the spring S. salar smolt migration period. Plasma chloride, plasma glucose, gill aluminium and gill Na(+)- and K(+)-ATPase levels in S. salar smolts were assessed in relation to ambient stream-water chemistry during this migration period. Changes in both plasma chloride and plasma glucose levels of S. salar smolts were strongly correlated with stream pH, and S. salar smolt mortality occurred in one study site with ambient stream pH between 5·6 and 5·8 during the study period. The findings from this study suggest that physiological effects on S. salar smolts are strongly correlated with stream pH and that in rivers and streams with low dissolved organic carbon (DOC) concentrations the threshold for physiological effects and mortality probably occurs at a higher pH and shorter exposure period than in rivers with higher DOC. Additionally, whenever an acidification event in which pH drops below 5·9 coincides with S. salar smolt migration in eastern Maine rivers, there is potential for a significant reduction in plasma ions of S. salar smolts.

[Visual acuity loss, the initial sympton of a spinal cord neoplasm]. / Disminución de agudeza visual, primer síntoma de un tumor medular.

CASE REPORT: A 46-year-old woman, who presented with right visual acuity loss, was found to have papilledema, and subsequently shown to have ventricular dilatation in a cerebral Magnetic Resonance Imaging (MRI) assessment. Elevated protein levels were found in the cerebrospinal fluid. Spinal MRI revealed the presence of a spinal cord neoplasm. After surgical removal of the tumor, which turned out to be a neurilemmoma, the patient's visual acuity was restored. DISCUSSION: The ocular presentation and the relationship between intracranial hypertension and spinal tumors are discussed. Likewise, the importance of considering the various causes of papilledema is emphasized.

Disminución de agudeza visual, primer síntoma de un tumor medular / Visual acuity loss, the initial symptom of a spinal cord neoplasm

Caso clínico: Se presenta el caso de una mujer de 46 años con disminución de agudeza visual en el ojo derecho y papiledema, con dilatación ventricular en la Resonancia Magnética Nuclear (RMN) cerebral. En la punción lumbar se detectó hiperproteinorraquia. La RMN medular reveló la presencia de una neoplasia de la médula espinal. La paciente recuperó la agudeza visual tras la extirpación quirúrgica del tumor, que resultó ser un neurilemoma. Discusión: Se comenta la presentación ocular y la fisiopatología de la hipertensión intracraneal en el tumor espinal. Asimismo se destaca la importancia del diagnóstico etiológico del papiledema

Case report: A 46-year-old woman, who presented with right visual acuity loss, was found to have papilledema, and subsequently shown to have ventricular dilatation in a cerebral Magnetic Resonance Imaging (MRI) assessment. Elevated protein levels were found in the cerebrospinal fluid. Spinal MRI revealed the presence of a spinal cord neoplasm. After surgical removal of the tumor, which turned out to be a neurilemmoma, the patient’s visual acuity was restored. Discussion: The ocular presentation and the relationship between intracranial hypertension and spinal tumors are discussed. Likewise, the importance of considering the various causes of papilledema is emphasized (Arch Soc Esp Oftalmol 2008; 83: 437-440)

Prescripción de antidiabéticos orales y uso racional de glibenclamida: Posibilidades de mejora / No disponible

Objetivo: Conocer la prescripción de antidiabéticos orales y el uso de la prescricipción especifica de las especialidades farmacologicas de glibenclamida con el fin de mejor nuestra eficiencia. Diseño: Descriptivo, transversal durante años 2001-2002. Emplazamiento: Comunidad de Madrid, área 4. Mediciones: Determinamos las dosis diarias definidas (DDD) y las dosis definidas por 1000 habitantes(DHD)de los antidiabeticos orales a nivel de área durante el periodo 20012002, así como de cada prescripción especifica de las especialidades farmaceuticas de glibenclamida. Calculamos el indice de buena prescripción en los equipos de glibenclamida (Norglicem/Euglucon+Daonil); así como el ahorro potencial de glibenclamida si se realizara con la especialidad de menor coste. Resultados: La prescripción de antidiabeticos orales 2001 versus 2002 aumentó de 22,19 a 24,69 DHD. La glibenclamida continua siendo el antidiabético oral más prescrito con 7,49 DHD, con una tendencia a disminuir su prescripción. La metformina es el segundo antidiabetico más prescrito con un incremento en su prescripción del 44.84. Existe una tendencia a la prescrición de antidiabéticos de reciente comercialización. La prescripción específica de las especialidades farmacéuticas de glibenclamida son las de mayor coste, existiendo una tendencia a la valoración el coste en los equipos. El ahorro potencial de glibenclamida en los equipos de atención primaria, de pres-cribir la especialidad de menor coste sería de 39.395 euros. Conclusión: El aumento de la población mayor, la prescripción de especialidades farmacéuticas de mayor coste y la aparición de nueva medicación, son factores que influyen en el coste del tratamiento oral de la diabetes (AU)

Aims. The objective of the study is determine the use of oral antidiabetic and the prescription of specific glibenclamide in primary health. Design. Across over, observational study during 2001-2002. Localization. Primary health area 4 of Madrid. Measurement. We determinate the DDD, DHD and cost of oral drugs in diabetic patients type 2. The prescription was taken from the data-base of the area We valorized the ratio of good prescription for glibenclamida (Norglicem/Daonil+Euglucon-5), and the possible reduction of the cost on oral antidiabetc drugs in glibenclamide by the equips of primary health care Results. The prescription of oral drugs increase during the period 2001 versus 2002 increase from 22.19 to 24.69 DHD. Glibenclamida was the oral drug more use in 2002 with 7.49 DHD, with a decrease of 0.75% versus 2001. Metformin is the second drug use and increase versus 2001 in 44.84%.There is high increase in the prescription of new drugs. The use of specific glibenclamida were those of more cost. The potential decrease of cost in glibenclamide by primary health is about 39.395 euros. A better prescription by the ratio (Norglicem/Daonil+Euglucom) is possible, only 3 of the 28 group study have level high of 1. Conclusion. The increase of the poblation , the high cost of the prescription drugs and the increase of new drugs are factor that influence in the cost of oral treatment in diabetic patients type 2 (AU)

Feasibility of a semiconductor dosimeter to monitor skin dose in interventional radiology.

The design and preliminary test results of a semiconductor silicon dosimeter are presented in this article. Use of this dosimeter is foreseen for real-time skin dose control in interventional radiology. The strong energy dependence of this kind of radiation detector is well overcome by filtering the silicon diode. Here, the optimal filter features have been calculated by numerical Monte Carlo simulations. A prototype has been built and tested in a radiological facility. The first experimental results show a good match between the filtered semiconductor diode response and an ionization chamber response, within 2% fluctuation in a 2.2 to 4.1 mm Al half-value layer (HVL) energy range. Moreover, the semiconductor sensor response is linear from 0.02 Gy/min to at least 6.5 Gy/min, covering the whole dose rate range found in interventional radiology. The results show that a semiconductor dosimeter could be used to monitor skin dose during the majority of procedures using x-rays below 150 keV. The use of this device may assist in avoiding radiation-induced skin injuries and lower radiation levels during interventional procedures.

Design and validation of instruments to measure knowledge.

BACKGROUND: Measuring health care providers' learning after they have participated in educational interventions that use experimental designs requires valid, reliable, and practical instruments. METHODS: A literature review was conducted. In addition, experience gained from designing and validating instruments for measuring the effect of an educational intervention informed this process. RESULTS: The eight main steps for designing, validating, and testing the reliability of instruments for measuring learning outcomes are presented. The key considerations and rationale for this process are discussed. Methods for critiquing and adapting existent instruments and creating new ones are offered. CONCLUSIONS: This study may help other investigators in developing valid, reliable, and practical instruments for measuring the outcomes of educational activities.

Instruments to measure cancer management knowledge of rural health care providers.

BACKGROUND: Instruments to measure cancer management knowledge of rural physicians, nurses, and pharmacists were needed to evaluate the effect of an educational intervention. Since such instruments did not exist, the authors designed and validated a new instrument for each discipline. METHODS: The design and validation process for these instruments are described. RESULTS: These three instruments were shown to be practical and to have high content and construct validity. Content validation demonstrated that all items were rated as essential or useful by 90% or more of the respondents. Construct validation show highly significant differences in mean scores among several levels of learners and practitioners as expected. CONCLUSIONS: These instruments may be useful to other investigators for measuring cancer management knowledge of rural physicians, nurses, and pharmacists.

Trimellitic anhydride-induced allergic response in the guinea pig lung involves antibody-dependent and -independent complement system activation.

Trimellitic anhydride (TMA) is one of many low molecular weight compounds known to cause occupational asthma. In our previous studies the TMA-induced allergic response in guinea pigs was attenuated by depletion of complement. Specifically, the leakage of red blood cells and infiltration of inflammatory cells into the lung after TMA challenge was significantly reduced. Thus, we hypothesize that in the presence of specific antibody, TMA activates the complement system and complement activation products play a role in mediating inflammatory cell infiltration into the lung and lung hemorrhage. Guinea pigs were sensitized by intradermal injection of TMA in corn oil. An increase in the complement activation product C3a was detected in bronchoalveolar lavage, but not in plasma, of both sensitized and nonsensitized guinea pigs after intratracheal challenge with TMA conjugated to GPSA (TMA-GPSA). In vitro experiments demonstrated that TMA-GPSA caused complement activation by antibody-dependent as well as antibody-independent pathways. In sensitized animals, TMA-GPSA challenge caused significant increases in eosinophils, neutrophils, and macrophages in lung, along with increases in red blood cells and protein in the airspace. The infiltration of eosinophils was unique in that the magnitude of the GPSA/TMA-GPSA effect was significantly different between nonsensitized and sensitized animals. C3a concentrations in BAL correlated with all measures of cell infiltration in sensitized animals, but not in nonsensitized animals. These data indicate that complement activation in the absence of antibody is not sufficient for the complete allergic response to occur. Both sensitization and the complement system are required for TMA-induced eosinophilia.

Lake Superior Rural Cancer Care Project, part I: an interventional trial.

PURPOSE: To date, effective cancer care and control intervention studies have been carried out largely in urban and suburban populations. This study was conducted to test innovative interventions, using experimental designs, to improve the care and outcomes of patients with cancer in rural settings. DESCRIPTION OF STUDY: The Lake Superior Rural Cancer Care Project (LSRCCP) tested an innovative, multimodal, multidisciplinary intervention that involved rural healthcare providers and their healthcare system. An experimental design was used, with the rural community as the unit of randomization. Outcomes were measured at three levels: rural providers' knowledge of cancer management, providers' practice performance, and patient outcomes. This 5-year study was conducted in rural areas of northern Minnesota, Wisconsin, and the western part of the Upper Peninsula of Michigan. RESULTS: Baseline data from the study are provided, and details of the design and methods are presented. The study outcomes are reported in part in "Lake Superior Rural Cancer Care Project Part II" in this issue and will be reported further in future issues. CLINICAL IMPLICATIONS: This article describes the hypotheses, design, and methods of the LSRCCP. The design and methods as well as the results of this study may be useful to cancer researchers and clinicians in rural areas across the United States.

Lake Superior Rural Cancer Care Project, part II: provider knowledge.

PURPOSE: The purpose of this article is to report the main learning outcomes of the Lake Superior Rural Cancer Care Project. DESCRIPTION OF STUDY: The authors designed and tested a multimodal intervention directed at rural providers and their healthcare systems in a large rural area in the north central United States. An experimental design was used to randomize rural providers at the group level. The intervention consisted of providing increased education for rural providers with a number of approaches, including the use of clinical opinion leaders. The main outcome of the intervention was knowledge scoring on discipline-specific cancer management tests. RESULTS: Knowledge scores for providers in the experimental group significantly increased from pretest to post-test: 66 to 79 for physicians (and physician assistants) (P=.02); 58 to 71 for nurses (P=.01); and 54 to 64 for pharmacists (P=.01). At post-test, participating providers in the experimental group performed significantly better on the knowledge tests (P <.01) than those in the control groups. CLINICAL IMPLICATIONS: This study may be the first to test educational interventions to improve rural providers' knowledge about cancer practice using an experimental design. The intervention may possibly change provider practice behaviors and, thus, patient outcomes, data that will be reported in a future issue. Finally, this educational intervention may prove useful for providers in other rural areas.

Accuracy of alternative approaches to capture-recapture estimates of disease frequency: internal validity analysis of data from five sources.

The authors used "internal validity analysis" to evaluate the performance of various capture-recapture methods. Data from studies with five overlapping, incomplete lists generated subgroups whose known sizes were compared with estimates derived from various four-source capture-recapture analyses. In 15 data sets unanalyzed previously (five subgroups of each of three new studies), the authors observed a trend toward mean underestimation of the known population size by 16-25%. (Coverage of the 90% confidence intervals associated with the method found to be optimal was acceptable (13/15), despite the downward bias.) The authors conjectured that (with the obvious exception of geographically disparate lists) most data sets used by epidemiologists tend to have a net positive dependence; that is, cases captured by one source are more likely to be captured by some other available source than are cases selected randomly from the population, and this trend results in a bias toward underestimation. Attempts to ensure that the underlying assumptions of the methods are met, such as minimizing (or adjusting adequately) for the possibility of loss due to death or migration, as was undertaken in one exceptional study, appear likely to improve the behavior of these methods.

Public health nurses' responses to domestic violence: a report from the Enhanced Domestic Abuse Intervention Project.

Public health nurses (PHNs) can play an important role in the detection of domestic violence. This study examines whether the introduction of a domestic violence assessment protocol by public health nurses in a maternal and child health visiting program increases the identification and referral rates of women experiencing domestic violence. Data collected from case files during the baseline year prior to the initiation of the protocol were compared to case file information after the protocol had been implemented. When the protocol was used, there was a higher rate of identification, although the difference was not statistically significant. Significantly more women, however, were provided with information about domestic violence resources after the protocol was in place, and significantly more women were referred to services in the second year after the protocol had been implemented. This study provides support for the use of a domestic violence protocol to improve the public health nursing response to domestic violence.

Recommendations for presentation and evaluation of capture-recapture estimates in epidemiology.

We propose 15 recommendations for approaches to capture-recapture analysis in epidemiology. We apply them to a report of such an analysis of a measles epidemic [McGilchrist et al., J Clinical Epidemiol 1996, 49: 293-296] and to comments thereon by R. C. Cormack [J Clinical Epidemiol 1999; 52: 909-914]. The latter challenged the utility of the data on the measles outbreak for any reliable capture-recapture estimates. We suggest that, adopting the perspective of W. Edwards Deming, one can only make judgments as to the reliability of capture-recapture data, methods, and derived estimates in the light of (i.e., conditional upon) their eventual intended use. Capture-recapture approaches "unreliable" from one perspective may be "reliable," and/or more appropriately, "useful" from another. We consider the utility of ancillary and ad hoc information that may be available or worth seeking to supplement a capture-recapture analysis. We use information within the study of McGilchrist et al. to illustrate how, with such ancillary information, one may overcome the main thrust of the objections of Cormack in situations in which one observes apparently anomalous or hard to understand data structures. Making certain simple assumptions we regard as plausible, we estimate the number of affected in the measles epidemic as between about 700-1300. We derive this from data on 502 cases in a Register, an ad hoc sample of 91 cases in one age group in the general population, and the report of 41 cases in both of these. Our result is only 15-30% the total implied by the estimates McGilchrist et al. derived with more complex methods and many assumptions in addition to our own. We discuss various approaches to evaluating "reliability" of our estimate conditional upon intended uses by policy makers.

The obese gene is expressed in lean littermates of the genetically obese mouse (C57BL/6J ob/ob).

Some individuals of the mixed group of "lean" littermates (+/ob and +/+) of (C57BL/6J ob/ob) often suggest phenotypic characteristics of ob/ob animals. Therefore, it was of interest to determine whether expression of the ob gene had physiological significance in +/ob animals. Body weight (BW), fasting blood glucose (FBG), and body core temperature (Tr) were monitored between 62 and 364 days of age in +/+ and +/ob mice. Among females but not males, +/ob mice were heavier (P = 0.003) and FBG levels were greater (P = 0.04) than in +/+ animals. Comparison of Tr indicated differences suggesting falling Tr in +/ob but rising Tr in +/+ mice with age in males but not females. Multivariate analysis of variance yielded genotype effects for both males (P = 0.002) and females (P = 0.02). BW, FBG, and Tr alone were sufficient at the 75% level for genotypic characterization and separation of +/? animals as +/ob or +/+; clearly, expression of the ob gene in heterozygotes of the +/ob animal may make the mixed +/? group inappropriate as lean controls.

An exact test for all-way interaction in a 2M contingency table: application to interval capture-recapture estimation of population size.

An exact conditional test for an M-way log-linear interaction in a fully observed 2M contingency table is formulated. From this is derived a procedure for interval estimation of the total count N in a 2M contingency table, one of whose entries is unobserved. This procedure has an immediate application to interval estimation of the size of a closed population from incomplete, overlapping lists of records, as in capture-recapture analysis of epidemiological data. Data on the prevalence of spina bifida in live births in upstate New York in 1969-1974 illustrate this application.

Marginal versus conditional versus 'structural source' models: a rationale for an alternative to log-linear methods for capture-recapture estimates.

Log-linear models for capture-recapture type data are widely used for estimating sizes of populations. Log-linear methods model conditional interactions between the sources. Often, however, the marginal associations are more appropriate and easier for the practitioner to conceptualize. Analyses here of previously published data on cases of spina bifida in upstate New York are used to show how the assumption that sources are conditionally independent can give biased estimates if in fact the sources are marginally independent. A plausible model for the structural sources of interactions between the sources of information about spina bifida cases is developed which implies marginal independence of two of the sources rather than conditional independence. Estimates of the population total based on marginal independence are derived and give larger estimates of the population total than those derived based upon conditional dependence. When investigators can in fact model the likely underlying relationships of the sources in the population, we suggest considering modelling the potential interdependencies of the sources, which we term 'structural source modeling'.

Validity of methods for model selection, weighting for model uncertainty, and small sample adjustment in capture-recapture estimation.

In log-linear capture-recapture approaches to population size, the method of model selection may have a major effect upon the estimate. In addition, the estimate may also be very sensitive if certain cells are null or very sparse, even with the use of multiple sources. The authors evaluated 1) various approaches to the issue of model uncertainty and 2) a small sample correction for three or more sources recently proposed by Hook and Regal. The authors compared the estimates derived using 1) three different information criteria that included Akaike's Information Criterion (AIC) and two alternative formulations of the Bayesian Information Criterion (BIC), one proposed by Draper ("two pi") and one by Schwarz ("not two pi"); 2) two related methods of weighting estimates associated with models; 3) the independent model; and 4) the saturated model, with the known totals in 20 different populations studied by five separate groups of investigators. For each method, we also compared the estimate derived with or without the proposed small sample correction. At least in these data sets, the use of AIC appeared on balance to be preferable. The BIC formulation suggested by Draper appeared slightly preferable to that suggested by Schwarz. Adjustment for model uncertainty appears to improve results slightly. The proposed small sample correction appeared to diminish relative log bias but only when sparse cells were present. Otherwise, its use tended to increase relative log bias. Use of the saturated model (with or without the small sample correction) appears to be optimal if the associated interval is not uselessly large, and if one can plausibly exclude an all-source interaction. All other approaches led to an estimate that was too low by about one standard deviation.

Internal validity analysis: a method for adjusting capture-recapture estimates of prevalence.

The authors propose a method for adjusting results of log-linear multi-source capture-recapture estimates of total population. The method compares the totals in some subpopulations of known size with estimates derived from various capture-recapture approaches to these subpopulations. The authors term such an approach an "internal validity analysis". Trends in the ratios of the estimates to the known true values of these subpopulations provide a plausible indicator of the bias of some types of estimates of the total population especially when underlying assumptions of the methods used have not been met in analysis of the total population. The authors apply this method to published data on an open population of injection drug users that had been previously analyzed with a standard capture-recapture analysis as if it were a closed population. Internal validity analysis suggests that the size of this population is about 15% greater than that previously estimated.