bluuebunny/crossref_metadata_2025 huggingface dataset:
Improving the sampling technique of arterialized capillary samples to obtain more accurate PaO2 measurements
Authors: Wimpress S , Vara D D , Brightling C E
Published: April 2005

Arterialized earlobe capillary blood samples (ELCS) have been used as a measurement of blood gas status for over 20 years. There is general acceptance that there is a strong correlation and limits of agreement between arterial and arterialized blood samples with respect to pH and PaCO2. Although the correlation between the arterial and arterialized PaO2 is good, the limits of agreement poor. Our aim was to improve the accuracy of this technique in the measurement of PaO2 by simultaneously monitoring the oxygen saturation by pulse oximetry whilst taking an ELCS. We hypothesize that significant discrepancies between the SaO2 and SpO2 highlight either a poorly arterialized sample or an over aerated sample from air bubbles. We compared the SpO2 with the SaO2 of an arterial sample from 27 inpatients. We used the limits of agreement between these samples to define the degree of discordance we would accept between SaO2 and SpO2 before repeat ELCS. Subsequently, 252 consecutive patients attending our respiratory physiology unit over a six-month period had an ELCS and simultaneous SpO2.If there was a discrepancy between SaO2 and SPO2 of > 2% the ELCS was repeated. There was a good correlation and limits of agreement between the SPO2 and arterial SaO2 (r = 0.97, mean difference + 95% limits of agreement: 0.34 + 2.68). A difference of more than 2% between arterialized SaO2 and SpO2 was identified in 21 patients out of 252 (8.3%) with SaO2 higher in two and lower in 19 (r = 0.96, mean difference +95% limits of agreement: 0.66 + 3.1). Repeat ELCS of these 21 samples reduced this discrepancy improving the concordance of the measurements (r = 0.98, mean difference + 95% limits of agreement: 0.47 + 1.0). In one case a difference of 3% remained between the saturations. We conclude that the addition of simultaneous pulse oximetry with ELCS will identify rogue measurements in about 8% of cases highlighting the need for repeat samples and thus increasing the accuracy of the measurement of PaO2 by ELCS.
Increased risk of depression in COPD patients with higher education and income
Authors: Lin Mei , Chen Yue , McDowell Ian
Published: April 2005

This study examined potential modifying effects of income and education on the relationship between chronic obstructive pulmonary disease (COPD) and depression. The analysis was based on 44 963 Canadians aged 35 years or more who participated in the Canadian National Population Health Survey in 1996–1997. Logistic regression analysis was used to examine the association between prevalence of depression and COPD according to sex, income adequacy or educational level. We used a bootstrap procedure to take sampling weights and design effects into account. People with COPD had twice the prevalence of depression compared to those without COPD. The association tended to be stronger in well–educated men [adjusted odds ratio (OR) = 3.02, 95% confidence interval (CI) = 1.04, 8.75] and women (OR = 2.60, 95% CI = 1.55, 4.38) than those less educated (men: OR = 1.19, 95% CI = 0.47, 3.05; women: OR = 1.93, 95% CI = 0.96, 3.87). An increased prevalence of depression associated with COPD was also found in women with higher household income (adjusted odds ratio = 4.57, 95% CI = 2.27, 9.19) than those with lower income. However, this pattern was not found in men. In conclusion, COPD patients with higher education are more likely to be depressed. The modifying effect of income may vary by gender. Possible reasons for these findings are explored.
Impact of long–term ventilation on patients–health status
Authors: Carone M , Donner C F
Published: April 2005

Therapy and rehabilitation of common causes of respiratory–induced disability are directed towards a reduction of exacerbations, minimization of symptom severity, and improvement, or at least maintenance, of the patient's health. Unfortunately, these diseases are frequently complicated by chronic respiratory failure (CRF), which determines a rapid increase in the impact of the disease on the patient's daily life and well–being. Under such circumstances, the effect of therapy on a patient's health status and well–being represents the most important subjective outcome of treatment. An adequate assessment of patient's quality of life can only be obtained from the patients themselves; that is, it requires direct measurement through the use of valid and reliable questionnaires, whether generic or disease–specific. The St George's Respiratory Questionnaire and the Maugeri Foundation Respiratory Failure Questionnaire have been shown to be applicable and reliable in patients on long– term ventilation.
Stability of Neuroendocrine and Behavioral Responsiveness in Aging Fischer 344/Brown-Norway Hybrid Rats
Authors: Kasckow John W. , Segar Tracy M. , Xiao Chun , Furay Amy R. , Evanson Nathan K. , Ostrander Michelle M. , Herman James P.
Published: April 2005

Aging in rodents and primates is accompanied by changes in hypothalamic-pituitary-adrenal (HPA) activity. We examined behavioral and neuroendocrine responses in 3, 15-, and 30-month-old F344/Brown-Norway rats. Basal corticosterone and ACTH levels did not differ with age, although ACTH responses, but not corticosterone responses to restraint stress, were significantly lower in the 30-month-old group relative to 3- and 15-month-old rats. Induction of c-fos mRNA in the paraventricular nucleus from restraint was not affected by age. Furthermore, there was an enhanced sensitivity to dexamethasone suppression in aged animals as evidenced by lesser ACTH and corticosterone release after dexamethasone administration. Evaluation of emotional behaviors in the forced swim test revealed no differences between the age groups. With fear conditioning, aged rats had decreased freeze times relative to middle-aged or young rats. Regression analysis revealed no significant correlations between the behavioral and HPA axis data in any group. Overall, the data suggest that an apparent decrease in pituitary drive is compensated for at the level of the adrenal, resulting in stable patterns of glucocorticoid secretion. The lack of a correlation between HPA axis measures and emotional as well as fear conditioning-related behaviors indicates that corticosteroid dysfunction may not predict age-related behavioral deficits in this aging model.
Calcium Has a Permissive Role in Interleukin-1β-Induced c-Jun N-Terminal Kinase Activation in Insulin-Secreting Cells
Authors: Størling Joachim , Zaitsev Sergei V. , Kapelioukh Iouri L. , Karlsen Allan E. , Billestrup Nils , Berggren Per-Olof , Mandrup-Poulsen Thomas
Published: April 2005

The c-jun N-terminal kinase (JNK) signaling pathway mediates IL-1β-induced apoptosis in insulin-secreting cells, a mechanism relevant to the destruction of pancreatic β-cells in type 1 and 2 diabetes. However, the mechanisms that contribute to IL-1β activation of JNK in β-cells are largely unknown. In this study, we investigated whether Ca2+ plays a role for IL-1β-induced JNK activation. In insulin-secreting rat INS-1 cells cultured in the presence of 11 mm glucose, combined pharmacological blockade of L- and T-type Ca2+ channels suppressed IL-1β-induced in vitro phosphorylation of the JNK substrate c-jun and reduced IL-1β-stimulated activation of JNK1/2 as assessed by immunoblotting. Inhibition of IL-1β-induced in vitro kinase activity toward c-jun after collective L- and T-type Ca2+ channel blockade was confirmed in primary rat and ob/ob mouse islets and in mouse βTC3 cells. Ca2+ influx, specifically via L-type but not T-type channels, contributed to IL-1β activation of JNK. Activation of p38 and ERK in response to IL-1β was also dependent on L-type Ca2+ influx. Membrane depolarization by KCl, exposure to high glucose, treatment with Ca2+ ionophore A23187, or exposure to thapsigargin, an inhibitor of sarco(endo)plasmic reticulum Ca2+ ATPase, all caused an amplification of IL-1β-induced JNK activation in INS-1 cells. Finally, a chelator of intracellular free Ca2+ [bis-(o-aminophenoxy)-N,N,N′,N′-tetraacetic acid-acetoxymethyl], an inhibitor of calmodulin (W7), and inhibitors of Ca2+/calmodulin-dependent kinase (KN62 and KN93) partially reduced IL-1β-stimulated c-jun phosphorylation in INS-1 or βTC3 cells. Our data suggest that Ca2+ plays a permissive role in IL-1β activation of the JNK signaling pathway in insulin-secreting cells.
Regulation of Parathyroid Hormone-Related Peptide by Estradiol: Effect on Tumor Growth and Metastasis in Vitro and in Vivo
Authors: Rabbani S. A. , Khalili P. , Arakelian A. , Pizzi H. , Chen G. , Goltzman D.
Published: April 2005

We evaluated the capacity of estradiol (E2) to regulate PTHrP production, cell growth, tumor growth, and metastasis to the skeleton in breast cancer. In estrogen receptor (ER)-negative human breast cancer cells, MDA-MB-231, and cells transfected with full-length cDNA encoding ER (S-30), E2 caused a marked decrease in cell growth and PTHrP production, effects that were abrogated by anti-E2 tamoxifen. E2 also inhibited PTHrP promoter activity in S-30 cells. For in vivo studies, MDA-MB-231 and S-30 cells were inoculated into the mammary fat pad of female BALB/c nu.nu mice. Animals receiving S-30 cells developed tumors of significantly smaller volume compared with MDA-MB-231 tumor-bearing animals. This change in tumor volume was reversed when S-30 cells were inoculated into ovariectomized (OVX) hosts. Inoculation of MDA-MB-231 cells into the left ventricle resulted in the development of lesions in femora and tibia as determined by x-ray analysis. In contrast, these lesions were significantly smaller in volume and number in animals inoculated with S-30, and this lower incidence was reversed in OVX animals. Bone histological analysis showed that the tumor volume to tissue volume ratio was comparable with that seen by x-ray. Immunohistochemical analysis showed that PTHrP production was inhibited in S-30 group and restored to levels comparable to that seen in MDA-MB-231 tumor-bearing animals when S-30 cells were inoculated in OVX animals. Collectively these studies show that E2 production is inversely correlated with PTHrP production and that the growth-promoting effect of PTHrP has a direct impact on tumor growth at both nonskeletal and skeletal sites.
Distinctive Actions of Membrane-Targeted Versus Nuclear Localized Estrogen Receptors in Breast Cancer Cells
Authors: Rai Deshanie , Frolova Antonina , Frasor Jonna , Carpenter Anne E. , Katzenellenbogen Benita S.
Published: April 2005

Estrogens regulate multiple activities in breast cancer cells, including proliferation. Whereas these hormones are most commonly known to regulate gene transcription through direct interaction with estrogen receptors (ERs) and with specific DNA sequences of target genes, recent studies show that ER also activates a number of rapid signaling events that are initiated at the cell membrane. To study the membrane-initiated effects of estrogen and separate them from the activities initiated by the nuclear localized ER in human breast cancer cells, we generated MDA-MB-231 breast cancer cell lines that have stably integrated either the wild-type nuclear form of ER (WT-ER) or a modified, membrane-targeted ER (MT-ER) that lacks a nuclear localization sequence and is dually acylated with a myristoylation sequence at the N terminus and a palmitoylation sequence at the C terminus. We demonstrate that MT-ER is membrane localized in the absence of estradiol (E2), showing punctate membrane and cytoplasmic speckles after E2 exposure. In contrast to WT-ER, MT-ER was not down-regulated by E2 or by antiestrogen ICI 182,780 exposure, and MT-ER failed to regulate endogenous E2-responsive genes highly up-regulated by WT-ER. Cells expressing MT-ER showed a greater serum response element-mediated transcriptional response that was partially inhibited by antiestrogen ICI 182,780. The MT-ER and WT-ER differentially altered ERK1/2 and Akt activities and the proliferation of breast cancer cells in response to E2. Hence, this study reveals distinct actions of the MT-ER vs. the WT-ER in effecting estrogen actions in breast cancer cells.
Role of the Basic Helix-Loop-Helix Transcription Factor, Scleraxis, in the Regulation of Sertoli Cell Function and Differentiation
Authors: Muir Tera , Sadler-Riggleman Ingrid , Skinner Michael K.
Published: April 2005

Sertoli cells are a postmitotic terminally differentiated cell population in the adult testis that form the seminiferous tubules and provide the microenvironment and structural support for developing germ cells. The transcription factors that regulate Sertoli cell differentiation remain to be elucidated. The basic helix-loop-helix transcription factors are involved in the differentiation of a variety of cell lineages during development and are expressed in pubertal Sertoli cells. A yeast-two-hybrid procedure was used to screen a Sertoli cell library from 20-d-old pubertal rats to identify dimerization partners with the ubiquitous E47 basic helix-loop-helix transcription factor. Scleraxis was identified as one of the interacting partners. Among the cell types of the testis, scleraxis expression was found to be specific to Sertoli cells. Analysis of the expression pattern of scleraxis mRNA in developing Sertoli cells revealed an increase in scleraxis message at the onset of puberty. Sertoli cells respond to FSH to promote expression of differentiated gene products such as transferrin that aid in proper development of the germ cells. Analysis of the hormonal regulation of scleraxis expression revealed a 4-fold increase in scleraxis mRNA in response to the presence of FSH or dibutryl cAMP in cultured Sertoli cells. An antisense oligonucleotide procedure and overexpression analysis were used to determine whether scleraxis regulates the expression of Sertoli cell differentiated gene products. An antisense oligonucleotide to scleraxis down-regulated transferrin promoter activity in Sertoli cells. A transient overexpression of scleraxis in Sertoli cells stimulated transferrin and androgen binding protein promoter activities and the expression of a number of differentiated genes. Observations suggest scleraxis functions in a number of adult tissues and is involved in the regulation and maintenance of Sertoli cell function and differentiation. This is one of the first adult and nontendon/chondrocyte-associated functions described for scleraxis.
Physiological Role for the Cochaperone FKBP52 in Androgen Receptor Signaling
Authors: Cheung-Flynn Joyce , Prapapanich Viravan , Cox Marc B. , Riggs Daniel L. , Suarez-Quian Carlos , Smith David F.
Published: April 2005

Molecular chaperones mediate multiple aspects of steroid receptor function, but the physiological importance of most receptor-associated cochaperones has not been determined. To help fill this gap, we targeted for disruption the mouse gene for the 52-kDa FK506 binding protein, FKBP52, a 90-kDa heat shock protein (Hsp90)-binding immunophilin found in steroid receptor complexes. A mouse line lacking FKBP52 (52KO) was generated and characterized. Male 52KO mice have several defects in reproductive tissues consistent with androgen insensitivity; among these defects are ambiguous external genitalia and dysgenic prostate. FKBP52 and androgen receptor (AR) are coexpressed in prostate epithelial cells of wild-type mice. However, FKBP52 and AR are similarly coexpressed in testis even though testis morphology and spermatogenesis in 52KO males are usually normal. Molecular studies confirm that FKBP52 is a component of AR complexes, and cellular studies in yeast and human cell models demonstrate that FKBP52 can enhance AR-meditated transactivation. AR enhancement requires FKBP52 peptidylprolyl isomerase activity as well as Hsp90-binding ability, and enhancement probably relates to an affect of FKBP52 on AR-folding pathways. In the presence of FKBP52, but not other cochaperones, the function of a minimally active AR point mutant can be dramatically restored. We conclude that FKBP52 is an AR folding factor that has critically important physiological roles in some male reproductive tissues.
Influence of peripheral blade angle on performance and stability of axial inducers
Authors: Mejri I , Bakir F , Kouidri S , Rey R
Published: April 2005

The goal of this paper is to compare the experimental performance within the cavitating regime for three axial inducers identified by the leading edge angle at the periphery of the blades, β1T = 10, 13, 15° and which will be noted as inducer 10°, inducer 13° and inducer 15°. The three-dimensional flow was analysed using the CFD code ‘CFX-BladeGENRELSP +’. This enabled us to explain the unstable and cavitating operation for off-design conditions. A brief bibliographic review of the cavitating regime and the outlines of the design method for the three axial inducers that were studied are first presented. Then, for these inducers; the main results are presented: 1) Overall performance—head coefficient and critical cavitation number (5 and 15 per cent drop) vs. the flow rate; 2) Vibration behaviour vs. the flow rate and the suction pressure; and 3) CFD results, which enable us to explain the unstable experimental behaviour for these inducers.
Prediction of an axial turbomachine performance degradation due to sand ingestion
Authors: Ghenaiet A , Tan S C , Elder R L
Published: April 2005

Erosion of compressor blades due to operation in particulate environments is a serious problem for the manufacturers and users of industrial and aeronautical gas turbines, because of drastic degradations in performance, mostly through blunting of blade leading edges, reduction of chord and increase of tip clearance and surface roughness. This paper presents a numerical study to assess the effects of erosion by sand ingestion on blade geometry deterioration and the subsequent performance degradation. These computations were carried out for an axial turbomachine in steps; first, calculations of particle trajectories and erosion resulting from cumulative impacts by sand particles (MIL-E 5007E, 0–1000 μm) were carried out, then, the required data were used in the estimation of performance degradation based on a mean-line method that included Lieblein and Koch-Smith loss correlations, in addition to an erosion fault model derived from blade geometry deterioration. This global procedure was successfully validated upon an axial fan stage, and can be generalized easily to other axial compressor designs.
Fast and Slow Skeletal Troponin I in Serum from Patients with Various Skeletal Muscle Disorders: A Pilot Study
Authors: Simpson Jeremy A , Labugger Ralf , Collier Christine , Brison Robert J , Iscoe Steve , Van Eyk Jennifer E
Published: April 2005

Background: Detection of skeletal muscle injury is hampered by a lack of commercially available assays for serum markers specific for skeletal muscle; serum concentrations of skeletal troponin I (sTnI) could meet this need. Moreover, because sTnI exists in 2 isoforms, slow (ssTnI) and fast (fsTnI), corresponding to slow- and fast-twitch muscles, respectively, it could provide insight into differential injury/recovery of specific fiber types. The purpose of this study was to investigate whether the 2 isoforms of sTnI and their modified forms are present in the blood of patients with various skeletal muscle disorders.

Methods: Serial serum samples were obtained from 25 patients with various skeletal muscle injuries. Serum proteins were separated by a modified sodium dodecyl sulfate–polyacrylamide gel electrophoresis protocol followed by Western blotting for sTnI with monoclonal antibodies specific to ssTnI and fsTnI.

Results: We observed (a) intact and, in some cases, degraded sTnI products; (b) evidence of posttranslational modifications in addition to proteolysis; and (c) differential detectability of both skeletal isoforms in the same patient.

Conclusions: It is possible to monitor both sTnI isoforms; this could lead to the development of new diagnostic assays for skeletal muscle damage.
Preludes to Power in the Highland Late Preceramic Period
Authors: Aldenderfer Mark
Published: April 2005

Although the dramatic differences in cultural complexity between the Pacific littoral cultures and those in the Andean highlands during the Late Preceramic Period have long been known, until recently explanations for them have not been forthcoming. In part, this has been because of shortcomings of empirical data from the highlands as well as a general lack of systematic attempts to look at the nature and origins of persistent leadership strategies and how these might be defined in the Andes. This chapter reviews the ethnographic data on incipient forms of persistent leadership, examines the archaeological record of the Late Preceramic in the highlands for signs of it, and suggests potential explanations for why persistent leadership is uncommon. Those forms of leadership that do appear in the Late Preceramic appear to be based on lineage principles and the control of religious beliefs through ritual practice and are found in ecological contexts of relative resource abundance.
The Evolution of Authority and Power at Chavín de Huántar, Peru
Authors: Rick John W.
Published: April 2005

The Early Horizon type site of Chavín de Huántar, located in the north‐central Andes of modern Peru, is distinguished by a long sequence of construction, as well as outstanding features such as abundant lithic art, use of cut stone in construction, a complex of underground gallery systems, and exceptional alteration of local land forms. This chapter explores the implications of these characteristics for the evolution of power and authority at this site across the later Initial Period and Early Horizon (approximately 1300 to 600 B.C.). Particular attention is focused on the concepts of power and authority in relation to religious belief systems and the intrinsic factors that might have connected the site's characteristics to a developing system for convincing populations to increasingly accept the dominance of a priestly leadership. These characteristics argue that not only were the emerging authorities at Chavín exceptionally creative in their manipulation of the human mind through landscape, architecture, images, sound, light, and the use of psychoactive drugs but also that this apparent highly planned ritual context demonstrates the very intentional and conscious strategies employed in the transformation of early politico‐religious organization.
Architecture and Power on the Wari–Tiwanaku Frontier
Authors: Nash Donna J. , Williams Patrick Ryan
Published: April 2005

The Wari Empire expanded and maintained control over many areas in the Andes for nearly four centuries (600–1000 C.E.). This chapter documents changes in power relations and political institutions on the Wari–Tiwanaku frontier. The settlements of both polities are well documented along their border in the Moquegua Valley of southern Peru where Wari controlled their provincial settlements from the lofty heights of Cerro Baúl. We assess the changing nature of the incorporation of different social groups within the Wari political structure of the frontier province over the course of the Middle Horizon. As Tiwanaku social groups joined the Wari colony, new sets of public expressions of power emerged, both from within these Tiwanaku groups and from the Wari administration itself. By examining artifactual remains and the design of architectural spaces, we elucidate the changing power relations between Wari, their subject populations, and their Tiwanaku neighbors.
The Expansion, Diversification, and Segmentation of Power in Late Prehispanic Nasca
Authors: Conlee Christina A.
Published: April 2005

During the Late Intermediate Period (A.D. 1000–1476) the organization and foundation of power in Nasca was transformed from earlier times. Previously, religious resources were central to the development and maintenance of the political and social hierarchy. After the collapse of the Wari Empire and a period of balkanization, the resources used to establish and maintain power broadened considerably. The expansion of the power base into new realms coincided with an increase in the number of local elites in the drainage. There was no longer a focus on regional ceremonial centers; instead, elites were able to build power through a variety of activities including exchange, craft production (with a focus on utilitarian items), feasting, community‐based ritual activities, and probably warfare and defense. During this period the levels of the political hierarchy grew and a more heterarchical type of regional polity developed.
Dynamic Display, Propaganda, and the Reinforcement of Provincial Power in the Inca Empire
Authors: Ogburn Dennis
Published: April 2005

A primary objective of the Inca state and other early empires was to maintain control over the inhabitants of conquered territories. In addition to overt tactics such as military force, resettlement, alliance formation, and cultural and economic integration, I suggest that many other activities of the Inca state also served to reinforce state power in the provinces. This was achieved by establishing and maintaining a “psychology of submission” in subject peoples through frequent reminders of imperial power, that is, advertising state control over labor. Display in this form was a major implicit element in various activities of the empire, such as the movement of armies, the transport of building stones from Cuzco to Ecuador, and the construction of imperial temples and palaces. These activities served as potent public demonstrations of the state's ability to mobilize large armies and control enormous amounts of labor. Propaganda also played a major role in maintaining the psychology of submission by disseminating information about those activities having an element of display and about other accomplishments of the state to people who did not witness them firsthand. Considered in light of these mechanisms of display and propaganda, many of the apparently wasteful activities of the Inca state can be understood as deliberate and integral to overall imperial strategies for maintaining control in the provinces.
Stream Fish Assemblages in Relation to Landscape Position and Local Habitat Variables
Authors: Smith Tamara A. , Kraft Clifford E.
Published: April 2005

The relative influence of local habitat variables and stream network position on fish assemblages was evaluated in this study of first‐order through third‐order streams within the Beaverkill–Willowemoc watershed in New York. We compared fish distribution and abundance over local and landscape scales by surveying 69 randomly selected tributaries within this 775‐km2 watershed. We used watershed‐level metrics of stream link magnitude, branch link, confluence link, downstream link, and stream order to evaluate the importance of stream network position upon fish assemblages. Results of canonical correspondence analysis indicated that six factors significantly influenced fish species abundance in our study watershed. The proportion of fine substrate, canopy cover, in‐stream vegetation, and water temperature were the four local habitat factors related to the abundance of fish species in this watershed; confluence link and stream order were the stream network position measures with the greatest influence on fish assemblages. Our results show that stream fish assemblages in the study watershed were influenced by a combination of small‐scale habitat variables and stream position within a watershed network. The significance of confluence link relative to that of other link measures designed to evaluate stream network position has never been previously established in a direct comparison. The usefulness of confluence link to characterize fish assemblages is consistent with efforts to identify metrics that are relevant to both watershed network geomorphology and ecology.
Two Alternative Juvenile Life History Types for Fall Chinook Salmon in the Snake River Basin
Authors: Connor William P. , Sneva John G. , Tiffan Kenneth F. , Steinhorst R. Kirk , Ross Doug
Published: April 2005

Fall Chinook salmon Oncorhynchus tshawytscha in the Snake River basin were listed under the Endangered Species Act in 1992. At the time of listing, it was assumed that fall Chinook salmon juveniles in the Snake River basin adhered strictly to an ocean‐type life history characterized by saltwater entry at age 0 and first‐year wintering in the ocean. Research showed, however, that some fall Chinook salmon juveniles in the Snake River basin spent their first winter in a reservoir and resumed seaward movement the following spring at age 1 (hereafter, reservoir‐type juveniles). We collected wild and hatchery ocean‐type fall Chinook salmon juveniles in 1997 and wild and hatchery reservoir‐type juveniles in 1998 to assess the condition of the reservoir‐type juveniles at the onset of seaward movement. The ocean‐type juveniles averaged 112–139 mm fork length, and the reservoir‐type juveniles averaged 222–224 mm fork length. The large size of the reservoir‐type juveniles suggested a high potential for survival to salt water and subsequent return to freshwater. Scale pattern analyses of the fall Chinook salmon spawners we collected during 1998– 2003 supported this point. Of the spawners sampled, an overall average of 41% of the wild fish and 51% of the hatchery fish had been reservoir‐type juveniles. Males that had been reservoir‐type juveniles often returned as small “minijacks” (wild, 16% of total; hatchery, 40% of total), but 84% of the wild males, 60% of the hatchery males, and 100% of the wild and hatchery females that had been reservoir‐type juveniles returned at ages and fork lengths commonly observed in populations of Chinook salmon. We conclude that fall Chinook salmon in the Snake River basin exhibit two alternative juvenile life histories, namely ocean‐type and reservoir‐type.
Distinction between Gastric Digestion and Evacuation in Black Bass Fed Piscine Prey
Authors: Wetzel James Edwin , Kohler Christopher C.
Published: April 2005

The terms “digestion” and “evacuation” are used interchangeably in studies of gastric processing in black basses Micropterus spp. We demonstrate that these processes are distinct and suggest that the differences may influence models involving the kinetics of gastric evacuation. Bolus (particulate matter) and residuum (bolus plus chyme (fluidized gastric contents)) sizes were used to examine gastric digestion (physical and chemical breakdown) and evacuation (passage of material from the stomach) in juvenile F1 backcross hybrid backcross black bass (largemouth bass M. salmoides × (spotted bass M. punctulatus × largemouth bass)). Thirty‐five black bass (2.477–6.398 g), each fed a single female zebra danio Brachydanio rerio (wet weight = 139–619 mg), were sampled at 4.5 h postprandially. Dry‐matter contents of the bolus, chyme, and residuum were related to relative prandium (meal) size and black bass wet weight. The presence of detectable chyme dry matter at all prandium sizes demonstrated that gastric digestion and evacuation were distinguishable during at least a portion of postprandial gastric processing. At 4.5 h, postprandial digestion clearly exceeded evacuation, which indicated the potential for differences in kinetics between the two processes. When the disparity between gastric residuum and bolus weights (i.e., the chyme contribution) was ignored, gastric dry‐matter content was underestimated by approximately 30% (4.5 h postprandially). As relative prandium size increased, the disparity between estimated prandium, residuum, and bolus dry weights increased; bolus and prandium dry weights showed the greatest disparity. Increases in black bass size and relative prandium size increased the amount of evacuated dry matter (prandium minus residuum), suggesting that models relating consumption and evacuation rates must consider relative prandium size and predator size.
The Fundamental Thermal Niche of Adult Landlocked Striped Bass
Authors: Bettoli Phillip W.
Published: April 2005

Researchers have described the temperatures selected by landlocked striped bass Morone saxatilis in different locales throughout the USA. However, seasonally low concentrations of dissolved oxygen (DO) in many systems prevented striped bass from using the cool waters (<22°C) they may have preferred. In Melton Hill Reservoir, a 92‐km‐long impoundment on the Clinch River in east Tennessee, 15 adult striped bass were tagged with temperature‐sensing radio tags and tracked for an average of 418 d in 1999–2000. Cold, hypolimnetic discharges from an upstream dam and heated discharge from a steam‐generating electric facility near the midpoint of this run‐of‐the‐river reservoir provided a broad range of temperatures in most seasons, and hypoxic habitats were uncommon even during stratification. The mean temperature occupied by striped bass varied seasonally (repeated‐measures analysis of variance, P < 0.0001) and was highest in summer (17.5°C), intermediate in spring and fall (15.4–16.9°C), and lowest in winter (13.0°C). The mean and modal temperatures occupied during the growing season (May–October 1999) were 17.5°C and 19.0°C, respectively; 30% of the observations were between 9°C and 15°C. These data indicate that the fundamental thermal niche of adult landlocked striped bass may be lower than literature estimates. These results also represent the first unbiased field estimates of the influence of season on the thermal ecology of adult striped bass. The thermal characteristics of habitats considered optimal in habitat suitability index models for adult landlocked striped bass (i.e., 18– 24°C) should be revised to include cooler waters.
Variability in Length–Weight Relationships Used to Estimate Biomass of Estuarine Fish from Survey Data
Authors: Kimmerer Wim , Avent Sean R. , Bollens Steven M. , Feyrer Fred , Grimaldo Lenny F. , Moyle Peter B. , Nobriga Matt , Visintainer Tammie
Published: April 2005

The biomass of fish populations is often calculated from abundance‐by‐length data using length–weight (LW) relationships from separate studies (e.g., from the literature). Estimates of biomass determined this way have two principal sources of error: (1) error in total numbers and size distribution of fish due to sampling variability; and (2) prediction error, including that arising from the use of a LW relationship from another time, place, population, or species. We developed LW relationships from 6,390 measurements of fish of 24 species in the San Francisco Estuary. Our principal objective was to evaluate the errors that arise when calculating biomass from length data. Data were obtained from four sampling studies (none designed for this purpose) and analyzed with analysis of covariance on log‐transformed data. Differences in LW relationships among studies were apparent. Five tests were applied to assess the influence of these differences on predictions of biomass from length data. Three of these tests indicated some bias arising from several sources, including differences in the range of lengths used to develop the relationships. The remaining two tests compared the sampling variability of two common fish species with variability and bias introduced by means of different alternative LW relationships from our data and from the literature. Length–weight relationships from the literature introduced some bias and somewhat more variability into the biomass estimates compared with estimates based on LW relationships obtained from the San Francisco Estuary. However, sampling error was the largest source of error in all cases. Although it is preferable to calculate biomass from LW relationships of fish from the same area and time period, the error induced by using relationships from other time periods, other areas, or the literature is typically small compared with sampling error, particularly when only relative measures of biomass are needed.
Caspian Tern Predation on Juvenile Salmonids in the Mid‐Columbia River
Authors: Antolos Michelle , Roby Daniel D. , Lyons Donald E. , Collis Ken , Evans Allen F. , Hawbecker Mike , Ryan Brad A.
Published: April 2005

We used a bioenergetics approach to determine the magnitude of predation by Caspian terns Sterna caspia on juvenile salmonids Oncorhynchus spp. in the mid‐Columbia River during 2000 and 2001. Caspian terns nesting on Crescent Island, Washington, located below the confluence of the Snake and Columbia rivers, consumed several hundred thousand juvenile salmonids each year of the study. Tern consumption of smolts was higher in 2001 (679,000 smolts; 95% confidence interval (CI): 533,000–825,000 smolts) than in 2000 (465,000 smolts; 95% CI: 382,000–547,000 smolts) as a result of an increase in tern breeding pairs, fledging success, and percentage of salmonids in the diet. On‐colony detection rates of passive integrated transponder tags from in‐river migrating smolts were also higher in 2001 (0.90–12.40%) than in 2000 (0.03–1.60%); the higher predation rates in 2001 were probably caused by extreme drought conditions that resulted in reduced spill from hydroelectric dams, lower river flows, and increased travel times for in‐river migrating smolts. Tern predation rates on juvenile steelhead O. mykiss were higher than those on yearling Chinook salmon O. tshawytscha in both years. The impacts of tern predation on steelhead smolts and yearling Chinook salmon from the Snake River were slight after accounting for the high proportion of smolts collected for transportation above Crescent Island. Survival of steelhead smolts from the upper Columbia River that are not transported above Crescent Island may be significantly affected by tern predation, particularly in low‐flow years. Appreciably higher predation rates on salmonids by Crescent Island terns than those observed in 2001 are unlikely considering the constraints on tern colony expansion, limited capacity for increased per capita smolt consumption by terns, and current high transportation rates for Snake River smolts.
Long‐Term Residence of Red Snapper on Artificial Reefs in the Northeastern Gulf of Mexico
Authors: Szedlmayer Stephen T. , Schroepfer Rebecca L.
Published: April 2005

Red snapper Lutjanus campechanus (N = 54) were tagged and tracked on 12 artificial reefs in the northeastern Gulf of Mexico. Fish were surgically implanted with ultrasonic transmitters and monitored with Vemco remote receivers and Sonotronics surface receivers from August 2000 to 2004. Four fish were manually tracked from the surface overnight, and their positions were recorded every hour for either 9 or 16 h. The total length of fish tagged was 589 ± 14 mm (mean ± SE). The number of detections by the remote receivers was 290,340 ± 44,696. By the end of this study, 5 fish were still being tracked, 8 fish had been lost immediately after tagging, 15 fish had been caught by fishers, and 26 fish had been lost after extended tracking. Red snapper were resident on artificial reefs for 218 ± 28 d, and residence time ranged from 1 to 595 d. We estimated that most (67%) of the tagged red snapper showed long‐term residence (117–595 d), 13% were resident for 8–91 d, and 20% left the tagging site soon after release (<4 d). Fish were resident on the same artificial reef over all seasons (winter, spring, summer, and fall), and no seasonal changes in proximity to the reef were detected. Red snapper left the receiver range (1.6 km) for short time periods; for example, fish 25 left the reef 285 times for 1–4 h over a 335‐d period. However, all fish spent most of their time (98%) within the receiver range. We detected diel changes in proximity to the reefs (N = 8), but patterns varied. In this study, red snapper showed high site fidelity over long time periods, which suggested that artificial reefs provided suitable habitat for red snapper in the northeastern Gulf of Mexico.
Gastrite varioliforme: freqüência e relação com a gastrite linfocítica
Authors: RIBEIRO Vera Lúcia Ângelo Andrade , BARBOSA Alfredo José Afonso , BARROS Carlos Alberto Silva
Published: April 2005

A gastrite varioliforme é uma entidade endoscópica caracterizada por nódulos elevados com base indurada, pregas tumefeitas e erosões elevadas. A relação entre este tipo especial de gastrite e a gastrite linfocítica, histologicamente definida pelo número aumentado de linfócitos intra-epiteliais, tem sido bastante discutida. Alguns autores descreveram elevada correlação entre estas duas entidades nosológicas, fato este contestado por outros grupos de autores. No Brasil, até onde se sabe, não há estudos sistematizados, nem relatos sobre a freqüência da gastrite varioliforme e sua correlação com a gastrite linfocítica. O presente estudo tem como objetivo estudar esta possível correlação. Foram estudados prospectivamente 200 pacientes consecutivos, submetidos a esofagogastroduodenoscopia e entre eles, apenas um caso de gastrite varioliforme (0,5%) foi diagnosticado. Numa segunda etapa foram estudados ainda 24 casos de gastrite varioliforme. Em nenhum destes casos foi diagnosticada gastrite linfocítica. Pode-se concluir, pelo presente estudo, que em nosso meio não há correlação entre a gastrite varioliforme endoscópica e a gastrite linfocítica histológica.
Fístulas arteriovenosas intra-hepáticas transtumorais (diagnóstico, importância e propostas de tratamento)
Authors: WIDMAN Azzo , SPERANZINI Manlio B. , OLIVEIRA Ilka R. S. , SAAD William A. , FRATEZZI Ayrton C. , CERRI Giovanni G.
Published: April 2005

Achados angiográficos de quatro pacientes portadores de tumor hepático com fístula arteriovenosa transtumoral intra-hepática (duas arterioveno portais e duas arterioveno hepáticas). Concomitantemente, é mostrado o resultado após embolização com cianoacrilato (Histoacryl®) em um paciente e após introdução de Lipiodol® em dois. São comentadas as características fisiopatológicas especiais de cada um dos dois tipos de fístula e as eventuais conseqüências da passagem da mistura quimioembolizante através do tumor: gênese de abcessos hepáticos, resposta irregular ao tratamento e complicações pulmonares. Apesar do Lipiodol® atravessar a fístula arteriovenosa e se alojar nos ramos terminais da veia porta ou no pulmão, através das veias hepáticas, não há contra-indicação para o tratamento quimioembólico, mas se torna conveniente a oclusão prévia da artéria nutriente desta comunicação mediante o uso de cianoacrilato (Hystoacryl®). Comenta-se que, deste modo, obtém-se o alívio da hipertensão portal nas fístulas arterioveno portais e se evitam as complicações decorrentes da passagem da mistura através da comunicação arteriovenosa em ambos os tipos. O diagnóstico, apesar de difícil, é importante e habitualmente é feito por meio da angiografia abdominal; todavia a ultra-sonografia com Doppler tornada mais sensível com o uso de contraste específico, pode alertar para a presença desta complicação vascular. Sugere-se a adoção de um algoritmo diagnóstico no estudo dos tumores hepáticos que inclua este exame, para a identificação destas fístulas, previamente ao tratamento quimioembólico. Conclui-se recomendando que este exame seja o primeiro na seqüência diagnóstica dos tumores hepáticos, por ser procedimento não-invasivo e que a arteriografia, por ser método invasivo, seja reservada para o tratamento.
Transplante isogênico de ilhotas de Langerhans no fígado de ratos: metodologia para separação e purificação das ilhotas de Langerhans
Authors: CHAIB Eleazar , PAPALOIS Apostolos , BRONS Ingrid G. M. , CALNE Roy Y.
Published: April 2005

A maior indicação do transplante de pâncreas ou de ilhotas de Langerhans é o diabetes mellitus do tipo I. O processo deve suprir as necessidades de insulina mantendo os níveis glicêmicos dentro da normalidade. Estudou-se o transplante isogênico de ilhotas de Langerhans no fígado de ratos WAG-RT1u. Com o método de separação e purificação das ilhotas de Langerhans obteve-se 2.834 ± 551,64 ilhotas com pureza de 83 ± 2,45%. O transplante de 2.834 ± 551,64 ilhotas de Langerhans no fígado destes animais, normalizou a glicemia que chegou a 35 mmol/L após indução do diabetes pela estreptozotocina, ficando em 9,62 ± 2,65 mmol/L nos primeiros 10 dias após o enxerto e 7,43 ± 0,27 mmol/L nos dias subseqüentes (P <0,05). O tempo médio de sobrevida das ilhotas transplantadas foi de 73 dias. Assim, o método para separação e purificação de ilhotas de Langerhans de ratos foi eficaz e o isotransplante de ilhotas de Langerhans em ratos foi efetivo na correção do diabetes induzido por estreptozotocina, havendo sobrevida média superior a 73 dias do enxerto e do animal quando os animais foram sacrificados.
Conseqüências nutricionais das alterações metabólicas dos macronutrientes na doença hepática crônica
Authors: MAIO Regiane , DICHI Jane Bandeira , BURINI Roberto Carlos
Published: April 2005

A doença hepática crônica cursa, freqüentemente, com anormalidades metabólicas de macronutrientes que propiciam o desenvolvimento ou agravamento da desnutrição protéico-energética. O papel central do fígado no metabolismo dos substratos energéticos e de proteínas e aminoácidos é revisto, de modo relacionado à desnutrição protéico-energética, em pacientes com hepatopatia crônica. Aceita-se que a redução da ingestão dietética seja um dos principais componentes etiológicos da desnutrição, particularmente em pacientes alcoolistas. Acresce-se a iatrogenia pela indicação de dietas restritas e jejum prolongado aos pacientes hospitalizados. Como fatores agravantes, há má absorção intestinal de gorduras e o hipermetabolismo associado ao alcoolismo agudo. Hipoglicemia, resistência insulínica, esteatose e hipertrigliceridemia constituem achados comuns, assim como níveis elevados de alguns aminoácidos com conseqüências neurológicas. O entendimento desses mecanismos fisiopatológicos permite a intervenção nutricional apropriada reduzindo a morbidade e mortalidade desses pacientes.
Carcinoma hepatocelular. Parte 1: considerações gerais e diagnóstico
Authors: CONTE Vinício Paride
Published: April 2005

São revistos aspectos relativos à incidência/prevalência, fatores de risco, proliferação celular (carcinogênese), anatomia patológica, progressão e evolução das hepatites virais B e C para o carcinoma hepatocelular inicial, alguns dados clínicos da doença, seu diagnóstico clínico, laboratorial e radiológico, com especial atenção à ultra-sonografia, Doppler, tomografia computadorizada e ressonância magnética.
Neoplasias primárias múltiplas em pacientes com câncer colorretal
Authors: CURY Marcelo de Souza , FORONES Nora Manoukian
Published: April 2005

Introdução - A presença de uma segunda neoplasia maligna, tendo sítio e histologia diferentes da primeira, define o conceito de neoplasias primárias múltiplas. Com o aumento da sobrevida dos pacientes com câncer, houve um aumento de neoplasias primárias múltiplas. Este estudo objetiva avaliar a freqüência de neoplasias primarias múltiplas em pacientes com diagnóstico de câncer colorretal do Setor de Oncologia da Disciplina de Gastroenterologia da Universidade Federal de São Paulo. Pacientes e Métodos - No período de 1993 a 1998, 145 pacientes com câncer colorretal foram acompanhados no Setor de Oncologia da Disciplina de Gastroenterologia da Universidade Federal de São Paulo. Destes, cinco pacientes (3,4%) tinham neoplasias primárias múltiplas. O segundo tumor foi confirmado por exame histológico, sendo excluídas as possibilidades de metástase. Resultados - A idade média dos doentes com neoplasias primárias múltiplas foi de 60,6 anos, quatro eram do sexo feminino e um do masculino, três apresentaram doença no reto, um no cólon direito e um no cólon esquerdo. Os outros sítios foram mama, útero, útero e vagina, pele e lábio. Um paciente foi a óbito e os outros estão em acompanhamento, sendo que dois, há mais de três anos. Dois pacientes tinham sido submetidos a radioterapia pélvica antes do aparecimento da neoplasia colorretal. Em um paciente o tumor colorretal antecedeu o outro câncer e em quatro apareceu posteriormente ao diagnóstico da outra neoplasia primária. Discussão - A prevalência de neoplasias primárias múltiplas foi de 3,4%, sendo maior no sexo feminino. Câncer de endométrio foi o outro tumor maligno mais freqüente. Quarenta por cento dos nossos pacientes foram submetidos a radioterapia. Acreditamos ser importante o acompanhamento dos pacientes para o diagnóstico precoce de uma nova neoplasia em qualquer paciente que já tenha apresentado um câncer.