bluuebunny/crossref_metadata_2025_split huggingface dataset:
Decreased actin solubility observed during ATP‐depletion is mimicked by severing agents but not depolymerizing agents in isolated and cultured proximal tubular cells
Authors: White Peter , Gu Luo , Chen Jing 
Published: March 2003

SummaryThe microvilli of the apical membrane of proximal tubule (PT) cells are supported by the underlying actin cytoskeleton. Ischaemic or anoxic ATP‐depletion leads to the disruption of the actin cytoskeleton, resulting in microvillar retraction and loss of membrane polarity. Using isolated PT cells, we have previously demonstrated that actin filaments (F‐actin) are likely severed during ATP‐depletion. A sequential extraction protocol revealed a decrease in actin solubility, resulting in the sequestration of a distinct F‐actin pool with the insoluble cellular complex in ATP‐depleted PT cells. We demonstrate here that decreased actin solubility is not only a reliable end‐marker of ATP‐depletion induced injury in freshly isolated PT cells, but also serves as a biochemical marker in the cultured proximal tubular cell line LLC‐PK1. In the present studies, we also investigated specific actin‐binding drugs to determine if they mimic the effects observed during energy depletion. Jasplakinolide (JP), a compound which binds F‐actin and prevents depolymerization, did not effect actin solubility during ATP‐depletion. Furthermore, swinholide A (SA), an F‐actin severing agent, resulted in decreased actin solubility, mimicking the effects of ATP‐depletion. Interestingly, latrunculin A (LA), an agent which depolymerizes F‐actin, did not reduce actin solubiltity, but rather resulted in an increase in digitonin‐soluble actin. Taken collectively, our results support previous work and suggest that disruption of the actin cytoskeleton during ATP‐depletion is mediated by F‐actin severing/fragmentation and not depolymerization. The differential effects of F‐actin disrupting agents and the consistencies observed in both models of ischaemic injury will provide a basis for a more detailed understanding of the pathological events of PT‐cell dysfunction.
PET imaging using a triple‐head gamma camera
Authors: Kuikka J. T. , Sohlberg A. , Husso‐Saastamoinen M. 
Published: March 2003

SummaryInterest in clinical fluorodeoxyglucose (FDG) imaging with multiple‐head gamma cameras is growing. To improve sensitivity, triple‐head coincidence imaging has been proposed. We report our initial experiences with a triple‐head coincidence gamma camera with 19 mm sodium iodide crystal thickness. Several positron emission tomography‐image quality parameters were evaluated using a Carlson and line source phantom. The system sensitivity with two‐dimensional axial shields was 830 cps kBq−1 ml−1 and maximum noise equivalent count rate 1900 cps for an 18F‐activity of 50 MBq. The imaging resolution was in central axial 7·0 mm and in central transaxial 7·6 mm, respectively. The average scatter fraction in scattered media was 29%. Clinical brain, heart and whole body images studies with [18F]FDG were acquired and they show good correlation with the phantom image quality. As a conclusion, triple‐head coincidence gamma camera provides relatively high‐count rate imaging with good contrast and resolution.
Physiological and symptomatic responses to cycling and walking in intermittent claudication
Authors: Askew C. D. , Green S. , Hou X. Y. , Walker P. J. 
Published: March 2003

SummaryTo shed light on the potential efficacy of cycling as a testing modality in the treatment of intermittent claudication (IC), this study compared physiological and symptomatic responses to graded walking and cycling tests in claudicants. Sixteen subjects with peripheral arterial disease (resting ankle:brachial index (ABI) < 0·9) and IC completed a maximal graded treadmill walking (T) and cycle (C) test after three familiarization tests on each mode. During each test, symptoms, oxygen uptake (VO2), minute ventilation (VE), respiratory exchange ratio (RER) and heart rate (HR) were measured, and for 10 min after each test the brachial and ankle systolic pressures were recorded. All but one subject experienced calf pain as the primary limiting symptom during T; whereas the symptoms were more varied during C and included thigh pain, calf pain and dyspnoea. Although maximal exercise time was significantly longer on C than T (690 ± 67 vs. 495 ± 57 s), peak VO2, peak VE and peak heart rate during C and T were not different; whereas peak RER was higher during C. These responses during C and T were also positively correlated (P<0·05) with each other, with the exception of RER. The postexercise systolic pressures were also not different between C and T. However, the peak decline in ankle pressures from resting values after C and T were not correlated with each other. These data demonstrate that cycling and walking induce a similar level of metabolic and cardiovascular strain, but that the primary limiting symptoms and haemodynamic response in an individual's extremity, measured after exercise, can differ substantially between these two modes.
Reference values for 99mTc‐MAG3 renography determined in healthy, potential renal donors
Authors: Clausen Thomas D. , Kanstrup Inge‐Lis , Iversen Jens 
Published: March 2003

SummaryBackground:  Reference values for 99mTc‐MAG3 renography were determined and the influence of sex and age (<50/≥50 years) was elucidated.Methods:  Sixty‐eight potential renal donors were evaluated by renography among other tests. Through examination of their records 41 healthy subjects with a normal renal arteriography were included in this study and the reference values of the functional distribution (the split function, SF), the time to peak renal parenchymal activity (Tmax) and the residual activity (RA) were calculated.Results:  For Tmax there was no significant influence of sex or age. Mean RA increased significantly with age (20·5 vs. 23·2%, P=0·03), but no difference was found between sexes. Mean SF (right kidney) was significantly higher among males.Conclusions:  When a diuresis of at least 2 ml min−1 is demanded we found the following normal ranges: SF >41%, Tmax <4·3 min and RA <33·7%.
Portapres and differential oscillometric finger blood pressure changes during deep breathing test in the assessment of BRS index
Authors: Jagomägi Kersti , Raamat Rein , Talts Jaak , Länsimies Esko , Jurvelin Jukka 
Published: March 2003

SummaryThe aim of this study was to investigate changes in the finger blood pressure during a deep breathing test (DB) and to find out whether the mean blood pressure might be used as a substitute for the systolic pressure in calculations of baroreflex sensitivity from data derived from the DB test. Continuous beat‐to‐beat finger pressure was recorded by the volume clamp method (Portapres model 2 monitor). In addition, the mean arterial pressure was recorded by the modified oscillometric method (UT9201 beat‐to‐beat monitor, University of Tartu, Estonia). Fifteen healthy volunteers, aged 25–56 years, were studied. The amplitude of respiration‐linked oscillations in the Portapres systolic (Psyst) and mean blood pressure (Pmean) was 22·2 ± 8·8 and 16·6 ± 5·8 mmHg, respectively. There was no significant difference between the amplitudes of induced changes in Pmean recorded by the two devices: the amplitude of oscillations in the mean blood pressure recorded by the differential oscillometric monitor was 16·0 ± 5·9 mmHg. The amplitude of oscillations in Psyst correlated significantly with the amplitude of oscillations in Pmean recorded either by Portapres or by UT9201 (r=0·95 and 0·98, respectively). The high correlation between the amplitudes of oscillations in mean and systolic blood pressure allows to conclude that mean arterial pressure changes during a DB test might be used instead of systolic pressure changes in calculation of the ratio of changes in pulse interval to changes in blood pressure, which is considered to reflect baroreflex sensitivity.
Fragmentation of Phragmites Habitats, Minimum Viable Population Size, Habitat Suitability, and Local Extinction of Moths, Midges, Flies, Aphids, and Birds
Authors: Tscharntke Teja 
Published: March 2003

Results from populations of insects and birds inhabiting Phragmites habitats were used to analyze effects of fragmentation. Flush‐crash cycles of the stem‐boring moth Archanara geminipuncta (Lepidoptera, Noctuidae) showed regionally concurrent, local extinctions despite an originally enormous population size (more than 180,000 adults), emphasizing the importance of metapopulation dynamics. Further, A. geminipuncta could be considered a keystone species, since shoot damage facilitated more than twenty species of herbivores, saprovores (of the caterpillars’ feces), and their parasitoids. The gall midge Lasioptera arundinis could survive only in side shoots induced by shoot damage of A. geminipuncta.Small Phragmites stands had thinner shoots (due to a water or nutrient deficiency) and shoots with more leaves (due to a better light supply) than large stands, thereby influencing species‐specific demands for habitat suitability and nutritiousness of reed tissue. In other words significance of habitat fragmentation could not be assessed by area alone. For example, two chloropid flies depending on thin, yellowish shoots survived only in small habitats or in the unmown edges of large habitats.Local persistence of Phragmites herbivores depended on much larger population sizes than could be expected from a population size sufficient to maintain genetic variation. At least 11,000 adults of the gall midge Giraudiella inclusa (or more than 84,000 galls) were necessary to avoid local extinction.With regard to conservation management of reed habitats, nature reserves should consist of old and unmown reeds, have fewer disturbed (particularly, fewer mown) habitat edges, measure more than two hectares (priority should go to the largest remaining fragments), and be surrounded by nearby reed habitats providing reservoir populations and diverse shoot types.
Effects of Habitat Fragmentation on the Abundance of Two Species of Leptodactylid Frogs in an Andean Montane Forest
Authors: Marsh David M. , Pearman Peter B. 
Published: March 2003

We used visual transect surveys to study the effects of forest fragmentation on abundance of two species of Leptodactylid frogs in an Andean forest of northern Ecuador. We measured the abundances of Eleutherodactylus chloronatus and E. trepidotus at various distances from the forest edge in one large forest patch (200 ha) and four adjacent forest fragments (0.25–5.3 ha). We also collected data on forest characteristics ( leaf litter thickness, understory density, and number and size of canopy trees) at each site. Abundance of E. chloronatus and E. trepidotus were respectively 3.5 and 2.1 times higher at sites in the large forest patch than at sites in the small fragments. Abundance of E. chloronatus was positively correlated with the log of patch size and inversely correlated with understory density. E. trepidotus abundance was not correlated with either patch size or understory density, but was inversely correlated with distance from the site to the large forest patch. The two species thus both appear to be affected by habitat fragmentation, but through different processes.Efectos de la Fragmentación del Hábitat en la Abundancia de dos Especies de Ranas Leptodactílidas en un Bosque de Montaña de los AndesUtilizamos datos de transectos lineales para estudiar los efectos de la fragmentación del bosque sobre dos especies de ranas en los Andes del norte de Ecuador. Medimos la abundancia de Eleutherodactylus chloronatus y E. trepidotus en sitios a distancias determinadas del horde del hosque en un fragmento grande (200 ha) y cuatro fragmentos menores adyacentes (0.25–5.3 ha). Obtuvimos dates sobre las características del bosque (espesor de la hojarasca, densidad del sotobosque, número de árboles en el dosel) en cada sitio. La abundancia de E. chloronatus y E. trepidotus fue 3.5 y 2. 1 veces mas alta en los sitios del fragmento grande one en los sitios de los fragmentos menores. La abundancia de E. chloronatus estuvo correlacionada con el logaritmo del tamaño del fragmento e inversamente correlacionada con la densidad del sotobosque. La abundancia de E. trepidotus no estuvo correlacionada con el tamaño del fragmento, ni con la densidad del sotobosque, pero sí con la distancia del sitio hasta el fragmento grande. Po lo tanto, las dos especies aparentemente son sustancialmente impactadas por la fragmentación del hábitat, pero a través de procesos diferentes.
Impact of Hunting on Large Vertebrates in the Mbaracayu Reserve, Paraguay
Authors: Hill Kim , Padwe Jonathan , Bejyvagi Carlos , Bepurangi Ambrosio , Jakugi Felipe , Tykuarangi Roberto , Tykuarangi Tito 
Published: March 2003

Over 1,400,000 m of line transect data were collected in collaboration with Ache Indians to determine encounter rates with all large vertebrates in the Mbaracayu Reserve Paraguay. The data were analyzed using logistic regression in order to determine the impact of human hunting on animal encounter rates in the reserve. The method controlled for effects of season, weather, time of day, and habitat in order to statistically isolate the human predation effect. Encounters with the animals themselves as well as fresh signs of their activity allowed us to determine whether lower encounter rates in hunted zones are simply due to increased wariness by target species. Our results show that areas near hunters are hunted more frequently, and that Dasypus novemcinctus, Cebus apella, Tapirus terrestris, and Mazama spp. are all encountered at lower rates in those areas than in unhunted zones. We were unable to show that encounter rates with other important game species have been affected by human hunting. Demonstration of local depletion by central place foragers is expected, however, and cannot be used to conclude that prey species are in danger of regional extirpation.Impacto de la Captura de Vertebrados Mayores en la Reserva de Mbaracayu, ParaguayDatos de mas de 1,400,000 m de transectos en linea fueron colectados en colaboración con los indios Ache para determinar las tasas de encuentro con vertebrados mayores en la reserva Mbaracayu del Paraguay. Los datos fueron analizados usando regresión logística para determinar el impacto de la cazería sobre la tasa de encuentros en la reserva. El método fue controlado para aislar el efecto de la depredación humana de los efectos de la estación, el clima, la hora del día y el tipo de habitat. Los encuentros con animales, así como marcas frescas de su actividad nos permitieron determinar si las tasas bajas de encuentros en las zonas de caza son simplemente debidas al incremento en la alerta de las especies blanco. Nuestros resultados muestran que las áreas cercanas a los cazadores son utilizadas mas frecuentemente y que Dasypus novemcinctus, Cebus apella, tapirus terrestris y Mazama spp. se encuentran todos en menor proporción que en las áreas no utilizadas para la cazería. No pudimos demostrar que las tasas de encuentros con otras especies de caza importantes han sido afectadas por la caza humana. Esperamos una disminución local debida a la presencia de forrajeros centrales, aunque esto no puede ser utilizado para concluir que las especies de presas se encuentran en peligro de una extirpación regional.
What Determines Quality in Maternity Care? Comparing the Perceptions of Childbearing Women and Midwives
Authors: Proctor Sue 
Published: March 2003

Background:In the current climate of consumer orientation in health care services, a clear need has emerged to understand the extent of consumer focus among primary health care professionals. Few studies have compared the beliefs of health care staff with those of patients. This study sought to identify and compare the perceptions of women and midwives concerning women's beliefs about what constitutes quality in maternity services.Methods:Focus groups were conducted from July 1994 to June 1997 with 38 pregnant and postnatal women, and 47 midwives who were based in two large maternity units in Yorkshire, England. Transcriptions of data were analyzed to identify broad themes.Results:Ten dimensions of quality were identified. Similarities between midwives and women included beliefs about the importance of the relationship between the two parties, desired attributes of staff, and the environment of care. Key differences included underestimating the importance of information antenatally and postnatally, the importance of continuity during labor, need for control and confidence in adjusting to the maternal role, and involvement of the woman's partner in the delivery of care.Conclusions:An understanding of the concerns of women by maternity care staff is important in the development of a woman‐focused service, in line with current policy recommendations, and has implications for risk management and improving the service quality for those who provide and experience the service. (BIRTH 25:2 June 1998)
Commercial Hospital Discharge Packs for Breastfeeding Women
Authors: Gupta J. K. , Nikodem V. C. 
Published: March 2003

A substantive amendment to this systematic review was last made on 23 March 1999. Cochrane reviews are regularly checked and updated if necessary.ABSTRACT Background: For centuries, there has been controversy around whether being upright (sitting, birthing stools, chairs, squatting) or lying down has advantages for women delivering their babies. Objectives: The objective of this review was to assess the benefits and risks of the use of different positions during the second stage of labour (i.e., from full dilatation of the cervix). Search strategy: Relevant trials are identified from the register of trials maintained by the Cochrane Pregnancy and Childbirth Group, and from the Cochrane Controlled Trials Register. Selection criteria: Trials were included which compared various positions assumed by pregnant women during the second stage of labour. Randomised and quasi‐randomised trials with appropriate follow‐up were included. Data collection and analysis: Trials were independently assessed for inclusion, and data extracted by the two authors. Disagreements would have been resolved by consensus with an editor. Meta‐analysis of data is performed using the RevMan software. Main results: Results should be interpreted with caution as the methodological quality of the 18 trials was variable. Use of any upright or lateral position, compared with supine or lithotomy positions, was associated with:

Reduced duration of second stage of labour (12 trials—mean 5.4 minutes, 95% confidence interval (CI) 3.9–6.9 minutes). This was largely due to a considerable reduction in women allocated to use of the birth cushion.
A small reduction in assisted deliveries (17 trials—odds ratio (OR) 0.82, 95% CI 0.69–0.98).
A reduction in episiotomies (11 trials—OR 0.73, 95% CI 0.64–0.84).
A smaller increase in second degree perineal tears (10 trials—OR 1.30, 95% CI 1.09–1.54).
Increased estimated risk of blood loss > 500ml (10 trials—OR 1.76, 95% CI 1.34–3.32).
Reduced reporting of severe pain during second stage of labour (1 trial—OR 0.59, 95% CI 0.41–0.83).
Fewer abnormal fetal heart rate patterns (1 trial—OR 0.31, 95% CI 0.11–0.91).

Reviewers' conclusions: The tentative findings of this review suggest several possible benefits for upright posture, with the possibility of increased risk of blood loss > 500 mL.Women should be encouraged to give birth in the position they find most comfortable. Until such time the benefits and risks of various delivery positions are estimated with greater certainty when methodologically stringent trials data are available, then women should be allowed to make informed choices about the birth positions in which they might wish to assume for delivery of their babies. Citation: Gupta JK, Nikodem VC. Women's position during second stage of labour (Cochrane Review). In: The Cochrane Library, Issue 4, 2000. Oxford: Update Software.
Breastfeeding Rates in Hong Kong: A Comparison of the 1987 and 1997 Birth Cohorts
Authors: Leung Gabriel M. , Ho Lai‐Ming , Lam Tai‐Hing 
Published: March 2003

ABSTRACT: Background: Low breastfeeding rates are an issue of international public health concern. Anecdotal reports suggest very low breastfeeding rates in Asia, but no population‐based studies have been conducted in the region. To determine the secular trend in breastfeeding practice in an Asian postindustrialized metropolitan community, we examined data from two population‐based birth cohorts of Hong Kong infants in 1987 and 1997.Methods: Annual population rates of breastfeeding initiation and duration were estimated from the birth cohorts, considering the change in breastfeeding rates over 10 years with correction for sociodemographic and birth characteristics. Factors associated with breastfeeding practice were identified using multivariate logistic regression modeling in a pooled analysis of individual data of both cohorts.Results: Overall, 26.8 percent of mothers initiated breastfeeding in 1987, and the rate increased to 33.5 percent in 1997. The rate would have been 27.4 percent in 1987 if the distributions of method of delivery, birthweight, birth order, maternal age, education, and employment status had been the same as in 1997. Only 7.6 percent of infants remained on the breast for more than 1 month in 1987 compared with 20.4 percent a decade later. Similarly, the rate for breastfeeding more than 3 months increased from 3.9 to 10.3 percent. Total breastfeeding duration was significantly longer in 1997 than 10 years earlier.Conclusions: This is the first systematic report of secular variations of breastfeeding rates in Asia. Hong Kong should set higher but realistic goals for breastfeeding that emphasize both initiation and maintenance. Given the wide latitude for improvement in terms of readily modifiable risk factors, such as smoking and cesarean section, these new goals should focus on improving rates in these targeted groups where breastfeeding rates are lowest. (BIRTH 29:3 September 2002)
Satisfaction with Team Midwifery Care for Low‐ and High‐Risk Women: A Randomized Controlled Trial
Authors: Biró Mary Anne , Waldenström Ulla , Brown Stephanie , Pannifex Jan H. 
Published: March 2003

ABSTRACT:Background: In 1996 a new model of maternity care characterized by continuity of midwifery care from early pregnancy through the postpartum period was implemented for women attending Monash Medical Centre, a tertiary level obstetric service, in Melbourne, Australia. This study's purpose was to assess the impact of this model on women's views and experiences of care during the antenatal, intrapartum, and postpartum periods compared with views of women receiving standard maternity care.Methods: One thousand low‐ and high‐risk women who booked at the antenatal clinic and met the eligibility criteria were randomly allocated to continuity of midwifery care from a group of seven midwives in collaboration with medical staff, or to standard care from a variety of midwives and medical staff. Women's views of care were measured by means of a postal questionnaire at four months after the birth.Results: Team midwifery care was associated with increased satisfaction with antenatal, intrapartum, and some aspects of postpartum care. The differences were most obvious for antenatal care.Conclusions: Continuity of midwifery care is realistically achievable in a tertiary obstetric referral service and is associated with increased satisfaction. (BIRTH 30:1 March 2003)