bluuebunny/crossref_metadata_2025 huggingface dataset:
Normal Brain Irradiation during Stereotactic Brain Implants Using Radioactive Iodine-125
Authors: Jani S.K. , Hitchon P.W. , Van Gilder J.C. , Chen Wen B.
Published: March 2007

Stereotactic interstitial brain implants deliver locally high radiation doses to treat malignant gliomas. Dose to the surrounding normal brain from an 125I implant has been compared with the dose from an external irradiation technique. Results show that an implant offers a higher dose gradient around the tumor and hence a lower dose to the normal brain. Moreover, some irregular-shaped tumors, while ideal for a stereotactic implant, may be very difficult to treat with external beams without delivering a significant radiation dose to the normal brain. An implant seems to be dosimetrically superior to external irradiation for delivering large tumor doses.
Does Epileptic Pain Really Exist?
Authors: Richardson D.E.
Published: March 2007

Painful seizures do exist, but are usually caused by uncontrolled muscle contractions that produce pain. Heretofore, no cases of seizures of the pain system have been reported. We will present a case of chest wall pain with episodic, severe exacerbation of the localized pain associated with focal muscle contractions. The episodes of severe pain could be provoked by stimulation of the internal capsule, producing repeated episodes of pain/muscle activity. The symptoms could be stopped by intravenous diazepam and reduced by periventricular grey stimulation.
Selective Neuromuscular Blockade for Intraoperative Electrocorticography
Authors: Abou-Madi M. , Trop D. , Lenis S. , Olivier A. , Leblanc R.
Published: March 2007

Local anesthesia is advocated for cortical mapping in certain neurological procedures. Occasionally, however, a modified general anesthetic is necessary. We describe a technique of balanced anesthesia in which the arm opposite to the craniotomy is selectively isolated from the effect of the neuromuscular blocking agent and hence preserves its motor response to cortical stimulation. The technique secures complete immobility of the patient during mapping of the brain, shortens the stimulation time, facilitates the localization of the motor cortex, precludes the development of full-blown seizures, increases safety and is well tolerated.
Effect of Commissurotomy on Complex Partial Epilepsy in Patients Without a Resectable Seizure Focus
Authors: Roberts David W. , Reeves Alexander G.
Published: March 2007

Twenty-fïve patients in a series of 51 undergoing partial or complete section of the corpus callosum for the treatment of intractable epilepsy experienced complex partial seizures among their seizure types preoperatively. Ten of these 25 patients have experienced no further complex partial seizures. Reduction in severity of seizures has been found in 11 of the 15 patients still experiencing this seizure type, and 3 have had greater than 80% frequency reduction. These fïndings are consistent with the electrophysiologic observations of Lieb on the relative unimportance of the hippocampal commissure in man and the behavioral observations of Quesney on unilateral versus bilateral temporal lobe seizure activity.
Experimental Anatomical Considerations of the Dorsal Root Entry Zone Lesions for Pain Relief
Authors: Kuroda R. , Nakatani J. , Kitano M. , Yamada Y. , Yorimae A.
Published: March 2007

Dorsal root entry zone (DREZ) lesions were made in the cervical dorsal horn in cat and monkey. Terminal degeneration was observed in the lateral cervical nucleus in cat and contralateral VPL in monkey by Fink-Heimer stain. WGA-HRP was injected in the cervical dorsal horn of cat and retrograde labelled cells were observed mainly in the raphe nucleus, parabrachial nucleus, locus coeruleus, Kölliker-Fuse nucleus, Eddinger-Westphal nucleus, and hypothalamic area, indicating that these descending fiber systems are involved by the DREZ lesion. The functional role of these fibers in regard to deafferentation pain relief seems now to be open to discussion.
Intraventricular Somatostatin-14, Arginine Vasopressin, and Oxytocin: Analgesic Effect in a Patient with Intractable Cancer Pain
Authors: Madrazo Ignacio , Franco-Bourland Rebecca E. , León-Meza Victor M. , Mena Iván
Published: March 2007

The analgesic effect of intraventricular somatostatin-14 (SOM-14), arginine vasopressin (AVP), and oxytocin (OT) were tested in one terminally ill cancer patient with a diffuse mesothelioma suffering intractable continuous and incapacitating thoracic pain. SOM-14 reduced pain by 90% for 48 min; AVP reduced pain by 95% for 75 min, and OT reduced pain by 88% for 77 min. The only notable side effects were seen after the administration of AVP, which induced anesthesia and flaccid paralysis of the lower limbs, from which the patient fully recovered after 20 h.
Computerized 22-ChanneI Stimulator for Limb Movement
Authors: Davis Ross , Eckhouse Richard , Patrick James F. , Delehanty Ann
Published: March 2007

The Nucleus 22-channel implantable hearing prosthesis (Cochlear Pty. Ltd., Lane Cove, Sydney, Australia) has been modified by computer programming (MOCO, Inc., Scituate, Mass. USA) into a functional electrical stimulator. Individual or multiple channels can be sequenced and adjusted for their amplitude, width and frequency of the pulse so that activation of single and multiple nerves can be achieved. Sciatic nerve branches (lateral and medial) of anesthetized rabbits were stimulated to produce single contractions or co-contraction at the ankle and simultaneous bilateral joint movements. The spiral (Helix) electrode was also found suitable in these experiments. The external equipment is being re-designed for a wearable ambulation unit to be used in paraplegic subjects.
Electrophysiological and Histological Study of Synaptic Connections between Lateral Geniculate Transplant and Host Visual Cortex
Authors: Hamasaki Tomoyuki , Hirakawa Kimiyoshi , Toyama Keisuke
Published: March 2007

The lateral geniculate nucleus (LGN) of fetal Wistar rats was transplanted to the visual cortex (VC) of 33 neonatal Wistar rats. Histological examination showed transplanted cells in all the host brains. Intensively labeled cells were demonstrated in the transplant by labeling with true blue. Electrophysiological studies with brain slice preparations demonstrated that the transplanted LGN sent axons and made excitatory monosynaptic connections mainly in layer IV of the VC area 17. Corticogeniculate projections were also demonstrated in the transplanted LGN.
Trabeculated Right Ventricular Free Wall in the Chicken Heart Forms by Ventricularization of the Myocardium Initially Forming the Outflow Tract
Authors: Rana M. Sameer , Horsten Noortje C.A. , Tesink-Taekema Sabina , Lamers Wout H. , Moorman Antoon F.M. , van den Hoff Maurice J.B.
Published: March 2007

Recent molecular lineage analyses in mouse have demonstrated that the right ventricle is recruited from anterior mesoderm in later stages of cardiac development. This is in contrast to current views of development in the chicken heart, which suggest that the initial heart tube contains a subset of right ventricular precursors. We investigated the fate of the outflow tract myocardium using immunofluorescent staining of the myocardium, and lineage tracer, as well as cell death experiments. These analyses showed that the outflow tract is initially myocardial in its entirety, increasing in length up to HH24. The outflow tract myocardium, subsequently, shortens as a result of ventricularization, contributing to the trabeculated free wall, as well as the infundibulum, of the right ventricle. During this shortening, the overall length of the outflow tract is maintained because of the formation of a nonmyocardial portion between the distal myocardial border and the pericardial reflections. Cell death and transdifferentiation were found to play a more limited contribution to the initial shortening than is generally appreciated, if they play any part at all. Cell death, nonetheless, plays an important role in the disappearance of the myocardial collar that continues to invest the aorta and pulmonary trunk around HH30, and in the separation of the intrapericardial arterial vessels. Taken together, we show, as opposed to some current beliefs, the development of the arterial pole is similar in mammals and birds.
Factors Influencing the Detection of Early CT Signs of Cerebral Ischemia
Authors: Wardlaw Joanna M. , Farrall Andrew J. , Perry David , von Kummer Rudiger , Mielke Orell , Moulin Thierry , Ciccone Alfonso , Hill Michael
Published: March 2007

Background and Purpose—

Early CT signs of cerebral ischemia are subtle. Little is known of which factors influence the detection of infarct signs. We compared neuroradiologists’ scan readings with those of other specialists involved in the care of stroke patients.

Methods—

We used the Internet to show 63 CT scans, all acquired <6 hours after stroke and representing different patient ages, times to scanning, stroke severity, and early CT signs of ischemia to physicians involved in stroke care. They completed a structured scan interpretation proforma over the Internet. We compared the detection of early ischemic signs stratified by severity and the effect of prior stroke between different specialties.

Results—

Among 207 observers, neuroradiologists saw significantly more of “any early ischemic changes” than did stroke physicians, general radiologists, geriatricians, or neurologists (all
P
<0.0001), predominantly due to neuroradiologists’ greater detection of “mild” hypoattenuation or swelling. Detection of “severe” hypoattenuation or swelling, and hyperattenuated arteries did not differ between specialties. Old infarcts impaired recognition of early ischemic signs. Nonneuroradiologists did not “overcall” signs. Years of scan-reading experience did not account for these differences, but neuroradiologists took, on average, 30 seconds longer to read each scan than did most other specialists (
P
<0.0001).

Conclusions—

Nonneuroradiologists should realize that they are unlikely to overcall signs, that old infarcts may distract them from seeing early ischemic signs, and read stroke CT scans more slowly, as these factors may help them perform more like neuroradiologists.
Dysregulated Bone Morphogenetic Protein Signaling in Monocrotaline-Induced Pulmonary Arterial Hypertension
Authors: Morty Rory E. , Nejman Bozena , Kwapiszewska Grazyna , Hecker Matthias , Zakrzewicz Anka , Kouri Fotini M. , Peters Dorothea M. , Dumitrascu Rio , Seeger Werner , Knaus Petra , Schermuly Ralph T. , Eickelberg Oliver
Published: March 2007

Background—

Mutations in the
bmpr2
gene, encoding the type II bone morphogenetic protein (BMP) receptor, have been identified in patients with pulmonary arterial hypertension (PAH), implicating BMP signaling in PAH. The aim of this study was to assess BMP signaling and its physiological effects in a monocrotaline (MCT) model of PAH.

Methods and Results—

Expression of BMP receptors Ib and II, and Smads 4, 5, 6, and 8, was downregulated in lungs but not kidneys of MCT-treated rats. Smad1 phosphorylation and expression of BMP/Smad target genes
id1
and
id3
was also reduced, although ERK1/2 and p38
MAPK
phosphorylation remained unaffected. BMP receptor and Smad expression, Smad1 phosphorylation, and induction of the BMP/Smad-responsive element of the
id1
promoter were reduced in pulmonary artery smooth muscle cells (PASMCs) from MCT-treated rats. As a consequence of impaired BMP/Smad signaling, PASMCs from MCT-treated rats were resistant to apoptosis induced by BMP-4 and BMP-7, and were also resistant to BMP-4 antagonism of proliferation induced by platelet-derived growth factor.

Conclusion—

BMP signaling and BMP-regulated physiological phenomena are perturbed in MCT-treated rats, lending solid support to the proposed roles for BMP signaling in the pathogenesis of human PAH.
Darbepoetin-Alpha Does Not Promote Microvascular Thrombus Formation in Mice
Authors: Lindenblatt Nicole , Menger Michael D. , Klar Ernst , Vollmar Brigitte
Published: March 2007

Objective—

Erythropoietin (EPO) treatment has become the standard treatment of renal anemia. Though a link between hematopoiesis-stimulating drugs and thrombosis has not been proven, it is generally assumed that systemic application of EPO and its analogues increases the risk for thrombotic events.

Methods and Results—

Here we show in C57BL/6J mice that 4-week treatment with the long-lasting EPO analogue darbepoetin-alpha (DPO) at a dose of 10 μg/kg/week induces a reduction of platelet reactivity using flow cytometry and Western blot analysis of tyrosine-specific platelet phosphorylation. Additionally, immunohistochemistry of endothelial adhesion molecule expression and ELISA of circulating endothelial activation markers demonstrated a reduced endothelial activation. Immunohistochemistry and RT-PCR analysis revealed a significant (
P
<0.05) increase of eNOS expression. Further, DPO did not exert prothrombogenic effects in a murine intravital microscopic thrombosis model of the cremaster muscle. The role of eNOS in prevention of DPO-mediated microvascular thrombosis is further underlined by a significantly accelerated thrombus formation on DPO treatment in eNOS (−/−) mice.

Conclusion—

Thus, DPO-related erythropoiesis with a raised hematocrit is not associated with an increased risk for thrombosis as long as endothelial NO production serves as compensatory mechanism.
Equilibria of Iterative Softmax and Critical Temperatures for Intermittent Search in Self-Organizing Neural Networks
Authors: Tiňo Peter
Published: March 2007

Kwok and Smith (2005) recently proposed a new kind of optimization dynamics using self-organizing neural networks (SONN) driven by softmax weight renormalization. Such dynamics is capable of powerful intermittent search for high-quality solutions in difficult assignment optimization problems. However, the search is sensitive to temperature setting in the softmax renormalization step. It has been hypothesized that the optimal temperature setting corresponds to the symmetry-breaking bifurcation of equilibria of the renormalization step, when viewed as an autonomous dynamical system called iterative softmax (ISM). We rigorously analyze equilibria of ISM by determining their number, position, and stability types. It is shown that most fixed points exist in the neighborhood of the maximum entropy equilibrium [Formula: see text] = (N−1, N−1, …, N−1), where N is the ISM dimensionality. We calculate the exact rate of decrease in the number of ISM equilibria as one moves away from [Formula: see text]. Bounds on temperatures guaranteeing different stability types of ISM equilibria are also derived. Moreover, we offer analytical approximations to the critical symmetry-breaking bifurcation temperatures that are in good agreement with those found by numerical investigations. So far, the critical temperatures have been determined only by trial-and-error numerical simulations. On a set of N-queens problems for a wide range of problem sizes N, the analytically determined critical temperatures predict the optimal working temperatures for SONN intermittent search very well. It is also shown that no intermittent search can exist in SONN for temperatures greater than one-half.
Connection Topology Selection in Central Pattern Generators by Maximizing the Gain of Information
Authors: Stiesberg Gregory R. , Reyes Marcelo Bussotti , Varona Pablo , Pinto Reynaldo D. , Huerta Ramón
Published: March 2007

A study of a general central pattern generator (CPG) is carried out by means of a measure of the gain of information between the number of available topology configurations and the output rhythmic activity. The neurons of the CPG are chaotic Hindmarsh-Rose models that cooperate dynamically to generate either chaotic or regular spatiotemporal patterns. These model neurons are implemented by computer simulations and electronic circuits. Out of a random pool of input configurations, a small subset of them maximizes the gain of information. Two important characteristics of this subset are emphasized: (1) the most regular output activities are chosen, and (2) none of the selected input configurations are networks with open topology. These two principles are observed in living CPGs as well as in model CPGs that are the most efficient in controlling mechanical tasks, and they are evidence that the information-theoretical analysis can be an invaluable tool in searching for general properties of CPGs.
Veterans' Party Identification, Candidate Affect, and Vote Choice in the 2004 U.S. Presidential Election
Authors: Teigen Jeremy M.
Published: March 2007

The 2004 U.S. presidential election was a wartime contest that entailed a great deal of discussion about the role that previous military service plays in elections for both candidates and the electorate. Using polling data throughout 2004, this article examines party identification, candidate affect, and vote choice preferences among veterans and nonveterans in the electorate. Despite widespread assumptions depicting the veteran population as deeply Republican, those with military experience in 2004 largely mirrored their nonveteran peers in terms of partisan identification, warmth toward candidates, ballot intentions, and vote choice. One important exception manifested after the “Swift Boat” advertisement in September, which impelled significant numbers of veterans who identify with the Democratic Party to express the intention to vote for George W. Bush.
Feminist Community Building in Ciudad Juárez
Authors: Swanger Joanna
Published: March 2007

Globalization and violence against women and children are processes of dehumanization and manifestations of alienation. Casa Amiga, a feminist organization in Ciudad Juárez, Mexico, is creating a local alternative to globalization through working to restore a sense of empowerment and multidimensional humanity—through community building. The small-scale “culture of solidarity” that Casa Amiga is constructing is in direct opposition to the narrow rules underpinning neoliberal globalization. Through the techniques of feminist therapy and consciousness-raising workshops, the members of Casa Amiga are constructing a culture based on sharing, reciprocity, responsibility, accountability, and mutual obligation. It seeks thus to enhance the welfare of all and thereby fulfill one of the broken promises of neoliberal globalization. The subtle resistance offered by Casa Amiga plays several crucial roles within new social movements that spectacular forms of resistance do not: (1) it is sustainable in the long term, (2) it tends to be far less alienating and can invite broad alliances, and (3) it tends not to occasion the kind of brutal, state-sponsored repression that squelches popular movements.
Fighting for the Forests
Authors: Kuecker Glen David
Published: March 2007

The history of a grassroots struggle against proposed mining projects in the Ecuadorian community of Junín reveals the centrality to its development of a “colono mentality” augmented by the conscientization of liberation theology. Links established between local organizers and NGOs in Ecuador and elsewhere helped the community to raise the costs of development sufficiently to drive the mining company away. A subsequent rise in the price of copper altered the comparative-advantage formula again, however, and a new mining company is seeking to win community members’ hearts and minds. While a Gramscian war of position is appropriate under present circumstances, it is highly vulnerable to capitalism’s capacity for survival.
Social Movements, Hegemony, and New Forms of Resistance
Authors: Vanden Harry E.
Published: March 2007

In Latin America, new social movements are vigorously and creatively engaging in grassroots organization and local and national mobilizations. Social movements in Bolivia, Brazil, and elsewhere have challenged the conduct of politics in their countries and the region. Their growth and militancy have generated whole new repertoires of action. Indeed, they raise the possibility of at least some form of “rule from below.” They have left the traditional twentieth-century parties far behind to create a nonauthoritarian, participatory political culture. Using existing political space to maximum effect, they are substantially strengthening participatory democratic practice and significantly altering political life. Less clear is whether they are, as Gramsci might conclude, coming together in a new cycle of subaltern actions that can break down the hegemony historically exercised by Latin America’s ruling classes.
The Film Criminal Justice
Authors: Cheatwood Derral , Petersen Rebecca D.
Published: March 2007

This research examines the use of the film Criminal Justice to consider the extent to which students’ race, gender, and university experience influence their determinations of guilt and perceptions of racism in the criminal justice system. The study samples 835 students in large criminal justice classes taught at an urban university in an eastern, predominately Black city and at an urban university in a southwestern, predominately Hispanic city. Analysis shows some statistically significant relationships, including those perceiving racism in the film as more likely to view the film’s defendant as not guilty, White students perceiving racism as more likely to see the defendant as not guilty, and males perceiving racism in the system as more likely to view the film’s defendant as not guilty. However, Black females perceiving racism as a factor in the film were significantly more likely to find the film’s defendant guilty than any other combination of race/ethnicity and gender, leaving an intriguing set of questions that are duly addressed.
The Next Step
Authors: Gilbert Michael J. , Settles Tanya L.
Published: March 2007

The challenge for modern crime-control policies is that they must work simultaneously across multiple environments within communities that are characterized by overlapping needs, issues, and service providers. Policy responses to crime must do more than capture and punish criminals, because crime is a deeply embedded social problem, and effective crime control requires more than a traditional justice system can offer. This article explores the effect of blending the theoretical underpinnings of restorative and community justice as an indigenous product of neighborhoods. Indigenous neighborhood processes may be able to address institutional and social structure problems to improve the quality of life for area residents and restorative outcomes for victims, the community, and the offender.
The New Israeli Law “The Dying Patient” and Relief of Suffering Units
Authors: Aminoff Bechor Zvi
Published: March 2007

The new Israeli Law “The Dying Patient” provides avenues for possible medical, ethical, and Halachic (Jewish religious law) solutions in view of the complexity of the treatment of an end-stage dementia patient. The establishment of a hospice-like setting for dementia patients in Israel, based on palliative treatment only, similar to the Jewish hospices in the United States, is extremely important. This article proposes a new, alternative approach and setting for patients with end-stage dementia that could pertain to the Israeli setting and could possibly also be acceptable in other countries. Short hospitalization periods of approximately 1 month and treatment in Relief of Suffering End-of-Life With Dementia Units may be a new palliative approach and present a possible solution for coping with the burden of the suffering of end-state dementia patients, their families, and the medical and nursing staff.
Should Age Limit Admission to the Intensive Care Unit?
Authors: Marik Paul E.
Published: March 2007

People who are older than 65 years of age are the fastest growing segment of the United States population. With the projected exponential increase in the number of elderly patients and the increasing burden of chronic disease, the number of elderly patients who will require treatment in an intensive care unit is expected to increase. Owing to the elderly patient's reduced life expectancy and higher intensive care unit and hospital mortality, it could be argued that elderly patients should not be admitted to the intensive care unit. However, an analysis of available data suggests that functional elderly patients have a favorable “long-term” outcome after intensive care unit admission. This suggests that age alone should not be used in making intensive care unit triage decisions.
A Critical Review of Complementary Therapies for Cancer-Related Fatigue
Authors: Sood Amit , Barton Debra L. , Bauer Brent A. , Loprinzi Charles L.
Published: March 2007

Purpose: To review the available literature on the use of complementary and alternative medicine (CAM) treatments for cancer-related fatigue with an aim to develop directions for future research. Methods: PubMed, EMBASE, CINAHL, PsycINFO, and SPORTDiscus were searched for relevant studies. Original clinical trials reporting on the use of CAM treatments for cancer-related fatigue were abstracted and critically reviewed. Results: CAM interventions tested for cancer-related fatigue include acupuncture, aromatherapy, adenosine triphosphate infusions, energy conservation and activity management, healing touch, hypnosis, lectinstandardized mistletoe extract, levocarnitine, massage, mindfulness-based stress reduction, polarity therapy, relaxation, sleep promotion, support group, and Tibetan yoga. Several of these interventions seem promising in initial studies. Conclusion: Currently, insufficient data exist to recommend any specific CAM modality for cancer-related fatigue. Therefore, potentially effective CAM interventions ready for further study in large, randomized clinical trials (eg, acupuncture, massage, levocarnitine, and the use of mistletoe) should be pursued. Other interventions should be tested in well-designed feasibility and phase II trials.
A Failed Initiative
Authors: Shields Carolyn M.
Published: March 2007

This case is developed for use in classes in which key ideas related to democracy, accountability, inclusion, finances, and social justice are introduced. It could be useful in a course on school reform or on democratic leadership. Although the case is fictional, it is a composite in which all events and information provided are “real.” The intent here is to help educational leaders think carefully about what constitutes democratic leadership, democratic processes, and democratic outcomes while being aware of the challenges of addressing the needs of minoritized groups without essentializing or pathologizing them.
In rats, oral oleoyl-DHEA is rapidly hydrolysed and converted to DHEA-sulphate
Authors: Serrano Marta , Grasa Maria del Mar , Fernández-López José Antonio , Alemany Marià
Published: March 2007

Background

Dehydroepiandrosterone (DHEA) released by adrenal glands may be converted to androgens and estrogens mainly in the gonadal, adipose, mammary, hepatic and nervous tissue. DHEA is also a key neurosteroid and has antiglucocorticoid activity. DHEA has been used for the treatment of a number of diseases, including obesity; its pharmacological effects depend on large oral doses, which effect rapidly wanes in part because of its short half-life in plasma. Since steroid hormone esters circulate for longer periods, we have studied here whether the administration of DHEA oleoyl ester may extend its pharmacologic availability by keeping high circulating levels.

Results

Tritium-labelled oleoyl-DHEA was given to Wistar male and female rats by gastric tube. The kinetics of appearance of the label in plasma was unrelated to sex; the pattern being largely coincident with the levels of DHEA-sulfate only in females, and after 2 h undistinguishable from the results obtained using labelled DHEA gavages; in the short term, practically no lipophilic DHEA label was found in plasma. After 24 h only a small fraction of the label remained in the rat organs, with a different sex-related distribution pattern coincident for oleoyl- and free- DHEA gavages. The rapid conversion of oleoyl-DHEA into circulating DHEA-sulfate was investigated using stomach, liver and intestine homogenates; which hydrolysed oleoyl-DHEA optimally near pH 8. Duodenum and ileum contained the highest esterase activities. Pure hog pancreas cholesterol-esterase broke down oleoyl-DHEA at rates similar to those of oleoyl-cholesterol. The intestinal and liver esterases were differently activated by taurocholate and showed different pH-activity patterns than cholesterol esterase, suggesting that oleoyl-DHEA can be hydrolysed by a number of esterases in the lumen (e.g. cholesterol-esterase), in the intestinal wall and the liver.

Conclusion

The esterase activities found may condition the pharmacological availability (and depot effect) of orally administered steroid hormone fatty acid esters such as oleoyl-DHEA. The oral administration of oleoyl-DHEA in order to extend DHEA plasma availability has not been proved effective, since the ester is rapidly hydrolysed, probably in the intestine itself, and mainly converted to DHEA-sulfate at least in females.
Effects of residence and race on burden of travel for care: cross sectional analysis of the 2001 US National Household Travel Survey
Authors: Probst Janice C , Laditka Sarah B , Wang Jong-Yi , Johnson Andrew O
Published: March 2007

Background

Travel burden is a key element in conceptualizing geographic access to health care. Prior research has shown that both rural and minority populations bear disproportionate travel burdens. However, many studies are limited to specific types of patient or specific locales. The purpose of our study was to quantify geographic and race-based differences in distance traveled and time spent in travel for medical/dental care using representative national data.

Methods

Data were drawn from 2001 National Household Travel Survey (NHTS), a nationally representative, cross-sectional household survey conducted by the US Department of Transportation. Participants recorded all travel on a designated day; the overall response rate was 41%. Analyses were restricted to households reporting at least one trip for medical and/or dental care; 3,914 trips made by 2,432 households. Dependent variables in the analysis were road miles traveled, minutes spent traveling, and high travel burden, defined as more than 30 miles or 30 minutes per trip. Independent variables of interest were rural residence and race. Characteristics of the individual, the trip, and the community were controlled in multivariate analyses.

Results

The average trip for care in the US in 2001 entailed 10.2 road miles (16.4 kilometers) and 22.0 minutes of travel. Rural residents traveled further than urban residents in unadjusted analysis (17.5 versus 8.3 miles; 28.2 versus 13.4 km). Rural trips took 31.4% longer than urban trips (27.2 versus 20.7 minutes). Distance traveled did not vary by race. African Americans spent more time in travel than whites (29.1 versus 20.6 minutes); other minorities did not differ. In adjusted analyses, rural residence (odds ratio, OR, 2.67, 95% confidence interval, CI 1.39 5.1.5) was associated with a trip of 30 road miles or more; rural residence (OR, 1.80, CI 1.09 2.99) and African American race/ethnicity (OR 3.04. 95% CI 2.0 4.62) were associated with a trip lasting 30 minutes or longer.

Conclusion

Rural residents and African Americans experience higher travel burdens than urban residents or whites when seeking medical/dental care.
A traditional Japanese-style salt field is a niche for haloarchaeal strains that can survive in 0.5% salt solution
Authors: Fukushima Tadamasa , Usami Ron , Kamekura Masahiro
Published: March 2007

Background

Most of the haloarchaeal strains have been isolated from hypersaline environments such as solar evaporation ponds, salt lakes, or salt deposits, and they, with some exceptions, lyse or lose viability in very low-salt concentrations. There are no salty environments suitable for the growth of haloarchaea in Japan. Although Natrialba asiatica and Haloarcula japonica were isolated many years ago, the question, "Are haloarchaea really thriving in natural environments of Japan?" has remained unanswered.

Results

Ten strains were isolated from a traditional Japanese-style salt field at Nie, Noto Peninsula, Japan by plating out the soil samples directly on agar plates containing 30% (w/v) salts and 0.5% yeast extract. They were most closely related to strains of three genera, Haladaptatus, Halococcus, and Halogeometricum. Survival rates in 3% and 0.5% SW (Salt Water, solutions containing salts in approximately the same proportions as found in seawater) solutions at 37°C differed considerably depending on the strains. Two strains belonging to Halogeometricum as well as the type strain Hgm. borinquense died and lysed immediately after suspension. Five strains that belonged to Halococcus and a strain that may be a member of Halogeometricum survived for 1–2 days in 0.5% SW solution. Two strains most closely related to Haladaptatus possessed extraordinary strong tolerance to low salt conditions. About 20 to 34% of the cells remained viable in 0.5% SW after 9 days incubation.

Conclusion

In this study we have demonstrated that haloarchaea are really thriving in the soil of Japanese-style salt field. The haloarchaeal cells, particularly the fragile strains are suggested to survive in the micropores of smaller size silt fraction, one of the components of soil. The inside of the silt particles is filled with concentrated salt solution and kept intact even upon suspension in rainwater. Possible origins of the haloarchaea isolated in this study are discussed.
Identification of high-risk subgroups in very elderly intensive care unit patients
Authors: de Rooij Sophia E , Abu-Hanna Ameen , Levi Marcel , de Jonge Evert
Published: March 2007

Introduction

Current prognostic models for intensive care unit (ICU) patients have not been specifically developed or validated in the very elderly. The aim of this study was to develop a prognostic model for ICU patients 80 years old or older to predict in-hospital mortality by means of data obtained within 24 hours after ICU admission. Aside from having good overall performance, the model was designed to reliably and specifically identify subgroups at very high risk of dying.

Methods

A total of 6,867 consecutive patients 80 years old or older from 21 Dutch ICUs were studied. Data necessary to calculate the Glasgow Coma Scale, Acute Physiology and Chronic Health Evaluation II, Simplified Acute Physiology Score II (SAPS II), Mortality Probability Models II scores, and ICU and hospital survival were recorded. Data were randomly divided into a developmental (n = 4,587) and a validation (n = 2,289) set. By means of recursive partitioning analysis, a classification tree predicting in-hospital mortality was developed. This model was compared with the original SAPS II model and with the SAPS II model after recalibration for very elderly ICU patients in the Netherlands.

Results

Overall performance measured by the area under the receiver operating characteristic curve and by the Brier score was similar for the classification tree, the original SAPS II model, and the recalibrated SAPS II model. The tree identified most patients with very high risk of mortality (9.2% of patients versus 8.9% for the original SAPS II and 5.9% for the recalibrated SAPS II had a risk of more than 80%). With a cut-point at a risk of 80%, the positive predictive values were 0.88 for the tree, 0.83 for the original SAPS II, and 0.87 for the recalibrated SAPS II.

Conclusion

Prognostic models with good overall performance may also reliably identify subgroups of very elderly ICU patients who have a very high risk of dying before hospital discharge. The classification tree has the advantage of identifying the separate factors contributing to bad outcome and of using few variables. Up to 9.5% of patients were found to have a risk to die of more than 85%.
Hawkeye: an interactive visual analytics tool for genome assemblies
Authors: Schatz Michael C , Phillippy Adam M , Shneiderman Ben , Salzberg Steven L
Published: March 2007

Genome sequencing remains an inexact science, and genome sequences can contain significant errors if they are not carefully examined. Hawkeye is our new visual analytics tool for genome assemblies, designed to aid in identifying and correcting assembly errors. Users can analyze all levels of an assembly along with summary statistics and assembly metrics, and are guided by a ranking component towards likely mis-assemblies. Hawkeye is freely available and released as part of the open source AMOS project http://amos.sourceforge.net/hawkeye.
Stereotactic Body Radiation Therapy in Multiple Organ Sites
Authors: Timmerman Robert D. , Kavanagh Brian D. , Cho L. Chinsoo , Papiez Lech , Xing Lei
Published: March 2007

Introduction

Stereotactic body radiation therapy (SBRT) uses advanced technology to deliver a potent ablative dose to deep-seated tumors in the lung, liver, spine, pancreas, kidney, and prostate.

Methods

SBRT involves constructing very compact high-dose volumes in and about the tumor. Tumor position must be accurately assessed throughout treatment, especially for tumors that move with respiration. Sophisticated image guidance and related treatment delivery technologies have developed to account for such motion and efficiently deliver high daily dose. All this serves to allow the delivery of ablative dose fractionation to the target capable of both disrupting tumor mitosis and cellular function.

Results

Prospective phase I dose-escalation trials have been carried out to reach potent tumoricidal dose levels capable of eradicating tumors with high likelihood. These studies indicate a clear dose-response relationship for tumor control with escalating dose of SBRT. Prospective phase II studies have been reported from several continents consistently showing very high levels of local tumor control. Although late toxicity requires further careful assessment, acute and subacute toxicities are generally acceptable. Patterns of toxicity, both clinical and radiographic, are distinct from those observed with conventionally fractionated radiotherapy as a result of the unique biologic response to ablative fractionation.

Conclusion

Prospective trials using SBRT have confirmed the efficacy of treatment in a variety of patient populations. Although mechanisms of ablative-dose injury remain elusive, ongoing prospective trials offer the hope of finding the ideal application for SBRT in the treatment arsenal.
Imaging and Alignment for Image-Guided Radiation Therapy
Authors: Balter James M. , Kessler Marc L.
Published: March 2007

Image-guided radiation therapy is an exciting new area that focuses heavily on the potential benefit of advanced imaging and image registration to improve precision, thus limiting morbidity and potentially allowing for safe delivery of increased dose. This review explores the issues surrounding the use of imaging and image registration for treatment planning and verification, with emphasis on the underlying patient model and alignment algorithms.
Advances in the Treatment of Localized Prostate Cancer: The Role of Anatomic and Functional Imaging in Men Managed With Radiotherapy
Authors: Speight Joycelyn L. , Roach Mack
Published: March 2007

Radiation therapy is an active modality in the management of local and regional prostate cancer, but can be curative only if all existing disease is encompassed within the treatment portal. In addition to the ability to deliver sufficient radiation dose, accurate targeting is critical to achieve better treatment outcomes. Failure to accommodate daily variations in setup and organ motion potentially limits the efficacy of sophisticated conformal techniques (three-dimensional conformal radiotherapy and intensity-modulated radiotherapy). Increased use of various online and real-time imaging techniques is an important step toward enhancing treatment accuracy. The incorporation of functional imaging techniques into treatment planning is another important step. The addition of biologic and metabolic information regarding the location and extent of disease combined with real-time online imaging will allow us to better determine where, how, and with what to treat appropriate targets and improve cure rates.
Intensity Modulating and Other Radiation Therapy Devices for Dose Painting
Authors: Galvin James M. , De Neve Wilfried
Published: March 2007

The introduction of intensity-modulated radiation therapy (IMRT) in the early 1990s created the possibility of generating dramatically improved dose distributions that could be tailored to fit a complex geometric arrangement of targets that push against or even surround healthy critical structures. IMRT is a new treatment paradigm that goes beyond the capabilities of the earlier technology called three-dimensional radiation therapy (3DCRT). IMRT took the older approach of using fields that conformed to the silhouette of the target to deliver a relatively homogeneous intensity of radiation and separated the conformal fields into many subfields so that intensity could be varied to better control the final dose distribution. This technique makes it possible to generate radiation dose clouds that have indentations in their surface. Initially, this technology was mainly used to avoid and thus control the dose delivered to critical structures so that they are not seriously damaged in the process of irradiating nearby targets to an appropriately high dose. Avoidance of critical structures allowed homogeneous dose escalation that led to improved local control for small tumors. However, the normal tissue component of large tumors often prohibits homogeneous dose escalation. A newer concept of dose-painting IMRT is aimed at exploiting inhomogeneous dose distributions adapted to tumor heterogeneity. Tumor regions of increased radiation resistance receive escalated dose levels, whereas radiation-sensitive regions receive conventional or even de-escalated dose levels. Dose painting relies on biologic imaging such as positron emission tomography, functional magnetic resonance imaging, and magnetic resonance spectroscopy. This review will describe the competing techologies for dose painting with an emphasis on their commonalities.
Conditional Inactivation of the E-Cadherin Gene in Thyroid Follicular Cells Affects Gland Development but Does Not Impair Junction Formation
Authors: Calì Gaetano , Zannini Mariastella , Rubini Patrizia , Tacchetti Carlo , D’Andrea Barbara , Affuso Andrea , Wintermantel Tim , Boussadia Oreda , Terracciano Daniela , Silberschmidt Daniel , Amendola Elena , De Felice Mario , Schütz Günther , Kemler Rolf , Di Lauro Roberto , Nitsch Lucio
Published: March 2007

We have conditionally inactivated the E-cadherin gene in the thyroid follicular cells of mouse embryo to unravel its role in thyroid development. We used the Cre-loxP system in which the Cre-recombinase was expressed under the control of the tissue-specific thyroglobulin promoter that becomes active at embryonic d 15. At postnatal d 7, thyroid follicle lumens in the knockout mice were about 30% smaller with respect to control mice and had an irregular shape. E-cadherin was almost completely absent in thyrocytes, β-catenin was significantly reduced, whereas no change in γ-catenin was detected. α-Catenin was also reduced on the cell plasma membrane. Despite the dramatic loss of E-cadherin and β-catenin, cell-cell junctions were not affected, the distribution of tight junction proteins was unaltered, and no increase of thyroglobulin circulating in the blood was observed. In addition, we found that other members of the cadherin family, the R-cadherin and the Ksp-cadherin, were expressed in thyrocytes and that their membrane distribution was not altered in the E-cadherin conditional knockout mouse. Our results indicate that E-cadherin has a role in the development of the thyroid gland and in the expression of β-catenin, but it is not essential for the maintenance of follicular cell adhesion.
Flutamide and Cyproterone Acetate Exert Agonist Effects: Induction of Androgen Receptor-Dependent Neuroprotection
Authors: Nguyen Thuy-Vi V. , Yao Mingzhong , Pike Christian J.
Published: March 2007

Androgens can exert profound effects on the organization, development, and function of the nervous system through activation of androgen receptors (ARs). Nonsteroidal and steroidal antiandrogens antagonize AR-mediated, classic genomic actions of androgens. However, emerging studies in nonneuronal cells indicate that antiandrogens can act as partial agonists for the AR. Here we investigated the effects of the antiandrogens flutamide and cyproterone acetate on neuroprotection induced by dihydrotestosterone (DHT). We observed that, although flutamide and cyproterone acetate blocked androgen-induced gene expression, they failed to inhibit DHT protection against apoptotic insults in cultured hippocampal neurons. Interestingly, flutamide and cyproterone acetate alone, like DHT, significantly reduced apoptosis. Furthermore, the protective actions of flutamide and cyproterone acetate were observed specifically in AR-expressing cell lines, suggesting a role for AR in the agonist effects of antiandrogens. Our results indicate that, in contrast to the classic antiandrogen properties of flutamide and cyproterone acetate, these AR modulators display agonist activities at the level of neuroprotection. These findings provide new insight into the agonist vs. antagonist properties of antiandrogens, information that will be crucial to understanding the neural implications of clinically used AR-modulating drugs.
On the Probability of Dizygotic Twins Being Concordant for Two Alleles at Multiple Polymorphic Loci
Authors: Nyholt Dale R.
Published: March 2007

Accurate determination of same-sex twin zygosity is important for medical, scientific and personal reasons. Determination may be based upon questionnaire data, blood group, enzyme isoforms and fetal membrane examination, but assignment of zygosity must ultimately be confirmed by genotypic data. Here methods are reviewed for calculating average probabilities of correctly concluding a twin pair is monozygotic, given they share the same genotypes across all loci for commonly utilized multiplex short tandem repeat (STR) kits. Numerous tools enabling convenient and accurate zygosity probability calculation may be accessed via the ZygProb homepage at http://genepi.qimr.edu.au/general/daleN/ZygProb/
How Long Do the Consequences of Parental Preference Last: A Study of Twins From Pregnancy to Young Adulthood
Authors: Trias L. Tuulikki , Ebeling Hanna E. , Penninkilampi-Kerola Varpu , Kunelius Anne M. , Tirkkonen Tiina T. , Moilanen Irma K.
Published: March 2007

We analyzed depressive and psychosomatic symptoms in relation to parental preference in 419 twins at the age of 22 to 30 years. Depressiveness was elicited with Children's Depression Inventory and reported as a total score and three subscales (low self-confidence, anhedonia and sadness) based on factor analysis as reported in a previous epidemiological study conducted in Finland. Items assessing nervous complaints and somatic symptoms were adapted from Finnish studies of juvenile health habits. Twins reported the preference in two directions: experienced parental preference towards either twin, and twin's own preference towards either parent. About half of the twins were from pairs where both twins experienced having been equally close to both parents, while about 30% were from ‘equal and mother's’ pair, where one twin evaluated having been preferred by the mother and the co-twin evaluated having been equally close to both parents. According to the twins' own preference, about one third of the twin pairs were ‘both equal’, one third ‘both mother's’ and one third ‘equal and mother's’. Those male twins who were equally close to both parents (experienced parental preference) had least total depressiveness, while females in the intermediate situation had the highest self-confidence and least anhedonia and nervousness. According to twins' own preference, twins who felt equally close to both parents had the least depressiveness and anhedonia. The intermediate position seems to be the best alternative, as these twins had the least symptoms.