bluuebunny/crossref_metadata_2025 huggingface dataset:
Fish diversity and ecology, habitats and fisheries for the un-dammed riverine axis Paraguay-Parana-Rio de la Plata (Southern South America)
Authors: Quirós R. , Bechara J. A. , de Resende E. K.
Published: June 2007

The riverine complex Paraguay-middle Parana-Rio de la Plata extends more than 3700 km southwards from its sources in the western hills of the Brazilian Shield to its discharge into the Rio de la Plata River. The high variety of habitats is reflected in the large diversity of its fish communities, which are dominated by characiform and siluriform fish species. The potamic axis is evolutionarily and ecologically open to fish movements and there are more than 400 fish species listed for the whole system, but only 100 species are common to both upper and lower basins. However, data limitations in some portions of the system need to be addressed before creation of an ichthyogeographic classification. The river basins that make up the potamic axis are low to medium developed and environmental pressures are unevenly distributed. Chemical pollution is a concern throughout. In the Pantanal, small hydro-projects and sedimentation from agricultural activities have had adverse effects on fish habitat inducing a loss of fish diversity. Un-dammed but more regulated and developed lowland rivers, may be impacted by upstream dams that may create unsuitable habitats for fish adapted to normal main channel conditions because they increase river flows during periods that were formerly low waters or change flows at random. The fisheries are lightly to moderately exploited compared to other subtropical and tropical riverine fisheries, and retain several of their original characteristics in less developed river reaches, although changes are evident. Large potamodromous fish are usually present in the catch, but the abundance of large piscivores is lower and fish size at catch is smaller. The development of the riverine system is expected to continue throughout the basin. If it is implemented as it was executed in the past, a continual loss of fish habitats and a general decrease in ecosystem health can be predicted.
Freshwater fishes of South America: Their biodiversity, fisheries, and habitats—a synthesis
Authors: Junk Wolfgang J.
Published: June 2007

Over long geological time periods, South America offered a large variety of waterbodies and habitats to aquatic organisms. Large river systems and streams of different water quality, different types of wetlands and high-altitude lakes favoured the development of a species-rich fish fauna with a large variety of adaptations. Therefore, South America is today a centre of megadiversity of fishes. In large areas, aquatic habitat health is still intact but environmental degradation is accelerating with negative impacts on the fish fauna. Inland fisheries are of great importance for protein supply of the local population, but stocks are already depleted in some areas. Fish culture is becoming increasingly important to supplement decreasing catches but cannot prevent loss of biodiversity. Lack of knowledge about fishes and their habitats, inefficient management of aquatic resources, large-scale uncoordinated modification of catchment areas, and the low priority given by the governments to fisheries and the protection of aquatic and wetland systems are reasons for decreasing fish stocks, deterioration of aquatic habitat health, and decreasing species numbers. A summary of the status of fish biodiversity, fishery, fish culture and habitat health in major South American rivers systems, the Altiplano and Patagonia is provided and the possibilities for sustainable management of aquatic resources and the protection of fish biodiversity are discussed.
The Magdalena River fresh water fishes and fisheries
Authors: Galvis Germán , Iván Mojica José
Published: June 2007

The Magdalena River Basin is the most important region of Colombia in terms of development and economy. About 80% of its population lives in this basin and traditionally its waters have produced more than 60% of fish consumed in the country. Nonetheless, from a production of nearly 80,000 ton yr− 1 in the 1970s, currently those fisheries produce only one tenth of that amount. This paper analyzes the different reasons of this collapse, and concludes that the causes are social, due to over fishing by landless displaced peasants trying to survive as fishermen.
Skin Impedance Measurements for Acupuncture Research: Development of a Continuous Recording System
Authors: Colbert Agatha P. , Yun Jinkook , Larsen Adrian , Edinger Tracy , Gregory William L. , Thong Tran
Published: June 2007

Skin impedance at acupuncture points (APs) has been used as a diagnostic/therapeutic aid for more than 50 years. Currently, researchers are evaluating the electrophysiologic properties of APs as a possible means of understanding acupuncture′s mechanism. To comprehensively assess the diagnostic, therapeutic and mechanistic implications of acupuncture point skin impedance, a device capable of reliably recording impedances from 100 kΩ to 50 MΩ at multiple APs over extended time periods is needed. This article describes design considerations, development and testing of a single channel skin impedance system (hardware, control software and customized electrodes). The system was tested for accuracy against known resistors and capacitors. Two electrodes (the AMI and the ORI) were compared for reliability of recording over 30 min. Two APs (LU 9 and PC 6) and a nearby non‐AP site were measured simultaneously in four individuals for 60 min. Our measurement system performed accurately (within 5%) against known resistors (580 kΩ–10 MΩ) and capacitors (10 nF–150 nF). Both the AMI electrode and the modified ORI electrode recorded skin impedance reliably on the volar surface of the forearm (r = 0.87 and r = 0.79, respectively). In four of four volunteers tested, skin impedance at LU 9 was less than at the nearby non‐AP site. In three of four volunteers skin impedance was less at PC 6 than at the nearby non‐AP site. We conclude that our system is a suitable device upon which we can develop a fully automated multi‐channel device capable of recording skin impedance at multiple APs simultaneously over 24 h.
Variation Analysis of Sphygmogram to Assess Cardiovascular System under Meditation
Authors: Liu Chuan-Yi , Wei Ching-Chuan , Lo Pei-Chen
Published: June 2007

In this article, we studied how meditation affects the characteristics of the cardiovascular system, mainly based on blood pressure waveforms (BPW). Four parameters derived from BPW include the rising slope (h1/t1), normalized height of T wave (h3/h1), normalized height of V3 valley (h4/h1) and normalized height of D wave (h5/h1), where t1 and hi, i = 1, … ,5 are quantitative features of the BPW waveform pattern. A larger value of h1/t1 reflects better heart ejection ability and aorta compliance. A larger value of h3/h1 may infer an arterial system with good elasticity. The decrease (increase) of h4/h1 parameter indicates the decrease (increase) of peripheral resistance of vessels. A larger value of h5/h1 indicates better artery elasticity and aortic valve function. In comparison with the control group, Zen‐meditation practitioners have more after‐meditation h1/t1, h3/h1 and h5/h1 increase, with more h4/h1 decrease, with statistical significance (P < 0.05). The observation allows us to infer that Zen meditation may effectively improve relevant characteristics of the cardiovascular system.
Screening of Bioactive Compounds from Moutan Cortex and Their Anti‐Inflammatory Activities in Rat Synoviocytes
Authors: Wu Mengjie , Gu Zhiyuan
Published: June 2007

Moutan Cortex, a widely used traditional Chinese medicine for the treatment of various diseases, is the root bark of Paeonia suffruticosa Andrews (Paeoniaceae). Most of the pharmacological investigations of Moutan Cortex have been addressed to its central nervous system activities, anti‐oxidative and sedative actions. Otherwise, there are few reports about the active compounds with anti‐inflammatory activity of Moutan Cortex. The aim of the present study was to screen and identify bioactive compounds with anti‐inflammatory effect from Moutan Cortex. With the aid of preparative high performance liquid chromatography (HPLC) technique, ethyl acetate and ethanol extract of Moutan Cortex were isolated into twenty‐two fractions. Bioactivities of these fractions were evaluated by measuring expression of tumor necrosis factor‐α (TNF‐α) in rat synoviocytes subjected to interleukin‐1β (IL‐1β). Eight compounds were isolated from six active fractions and identified by HPLC/MSn. Purified compounds, paeoniflorin, paeonol and pentagalloylglucose resulted in dose‐dependent inhibition of TNF‐α synthesis and IL‐6 production in synoviocytes treated with proinflammatory mediator. These results suggested that paeonol, paeoniflorin, glycosides and pentagalloylglucose contribute to the anti‐inflammatory effect of Moutan Cortex.
Seasonal Variations in Mood and Behavior in Romanian Postgraduate Students
Authors: Soriano Joseph J. , Ciupagea Constantin , Rohan Kelly J. , Neculai Dorin B. , Yousufi Samina M. , Guzman Alvaro , Postolache Teodor T.
Published: June 2007

To our knowledge, this paper is the first to estimate seasonality of mood in a predominantly Caucasian sample, living in areas with hot summers and a relative unavailability of air conditioning. As a summer pattern of seasonal depression was previously associated with a vulnerability to heat exposure, we hypothesized that those with access to air conditioners would have a lower rate of summer seasonal affective disorder (SAD) compared to those without air conditioning. A convenience sample of 476 Romanian postgraduate students completed the Seasonal Pattern Assessment Questionnaire (SPAQ), which was used to calculate a global seasonality score (GSS) and to estimate the rates of winter- and summer-type SAD. The ratio of summer- vs. winter-type SAD was compared using multinomial probability distribution tests. We also compared the ratio of summer SAD in individuals with vs. without air conditioners. Winter SAD and winter subsyndromal SAD (S-SAD) were significantly more prevalent than summer SAD and summer S-SAD. Those with access to air conditioners had a higher, rather than a lower, rate of summer SAD. Our results are consistent with prior studies that reported a lower prevalence of summer than winter SAD in Caucasian populations. Finding an increased rate of summer SAD in the minority of those with access to air conditioners was surprising and deserves replication.
Effect of Lead on the Transformation of Urea-N in Fly Ash-Contaminated Soils under Different Moisture Regimes
Authors: Das D. K. , Bashetti P. , Naik S. K. , Sur Pintu
Published: June 2007

Urea is applied to soil for plant growth and undergoes various changes while in the soil. The mobility of heavy metals changes with the transformation of urea applied to the soil that, in turn, affects the activity of microbial biomass. The objective of this study was to determine the interaction between lead (Pb) and urea under two moisture regimes (60% and saturated water contents). At 60% water content, the amount of NH4-N decreased with the incubation time, irrespective of Pb and urea applied, while the amount of NO3-N content in the soil gradually increased with the incubation period to 28 days, and such an increase was counteracted by application of Pb. The amount of NO3-N content was higher than that of NH4-N, however, under saturated moisture condition, the amount of NH4-N was increased with the incubation time regardless of the levels of Pb application. The amount of NO3-N content in the soil gradually decreased with the advance of incubation at saturated condition. Although application of urea increased the NO3-N content in the soil, such an increase was suppressed by the application of different levels of Pb at water saturated condition throughout the incubation period.
Eliminating Postoperative Nausea and Vomiting in Outpatient Surgery with Multimodal Strategies including Low Doses of Nonsedating, Off-Patent Antiemetics: Is “Zero Tolerance“ Achievable?
Authors: Skledar Susan J. , Williams Brian A. , Vallejo Manuel C. , Dalby Patricia L. , Waters Jonathan H. , Glick Ronald , Kentor Michael L.
Published: June 2007

For ondansetron, dexamethasone, and droperidol (when used for prophylaxis), each is estimated to reduce risk of postoperative nausea and/or vomiting (PONV) by approximately 25%. Current consensus guidelines denote that patients with 0–1 risk factors still have a 10–20% risk of encountering PONV, but do not yet advocate routine prophylaxis for all patients with 10–20% risk. In ambulatory surgery, however, multimodal prophylaxis has gained favor, and our previously published experience with routine prophylaxis has yielded PONV rates below 10%. We now propose a “zero-tolerance” antiemetic algorithm for outpatients that involves routine prophylaxis by first avoiding volatile agents and opioids to the extent possible, using locoregional anesthesia, multimodal analgesia, and low doses of three nonsedating off-patent antiemetics. Routine oral administration (immediately on arrival to the ambulatory surgery suite) of perphenazine 8 mg (antidopaminergic) or cyclizine 50 mg (antihistamine), is followed by dexamethasone 4 mg i.v. after anesthesia induction (dexamethasone is avoided in diabetic patients). At the end of surgery, ondansetron (4 mg i.v., now off-patent) is added. Rescue therapy consists of avoiding unnecessary repeat doses of drugs acting by the same mechanism: haloperidol 2 mg i.v. (antidopaminergic) is prescribed for patients pretreated with cyclizine or promethazine 6.25 mg i.v. (antihistamine) for patients having been pretreated with perphenazine. If available, a consultation for therapeutic acupuncture procedure is ordered. Our approach toward “zero tolerance” of PONV emphasizes liberal identification of and prophylaxis against common risks.
Pea Seedling Histaminase as a Novel Therapeutic Approach to Anaphylactic and Inflammatory Disorders
Authors: Masini Emanuela , Bani Danielle , Marzocca Cosimo , Mateescu Mircea Alexandru , Mannaioni Pier Francesco , Federico Rodolfo , Mondovì Bruno
Published: June 2007

Amine oxidases (AOs) are ubiquitous enzymes involved in the metabolism of biogenic amines. Copper AOs (Cu-AOs) catalyze the oxidative deamination of primary amine groups of several biogenic amines, such as putrescine, cadaverine, and histamine. In the present review, the effects of a plant amine oxidase (Cu-AO, histaminase, EC1.4.3.6) purified from pea seedlings in the modulation of IgE-mediated allergic reactions, and in the prevention of cardiac and splachnic postischemic reperfusion damage are reported.
Advances in Pediatric Urologic Laparoscopy
Authors: Smaldone M. C. , Polsky E. , Ricchiuti D. J. , Docimo S. G.
Published: June 2007

The spectrum of laparoscopic surgery in children has undergone a dramatic evolution. Initially used as a diagnostic modality for many pediatric urologists, complex as well as reconstructive procedures are now being performed laparoscopically. Laparoscopic orchiopexy and nephrectomy are well established and are being performed at many centers. Laparoscopic partial nephrectomy, adrenalectomy, and dismembered pyeloplasty series have reported shortened hospital stays and operative times that are comparable to that of open techniques or are decreasing with experience. The initial experiences with laparoscopic ureteral reimplantation and laparoscopic-assisted bladder reconstructive surgery have been described, reporting encouraging results with regards to feasibility, hospital stay, and cosmetic outcome. This report will provide a directed review of the literature to establish the current indications for laparoscopy in pediatric urologic surgery.
Open Surgery for Localized RCC
Authors: Vander Eeckt Kathy , Joniau Steven , Van Poppel Hein
Published: June 2007

The only possibility for cure in localized renal cell carcinoma (RCC) is surgery. Open radical nephrectomy (RN), as described by Robson, has long been the gold standard. Nevertheless, as a consequence of the increased use of abdominal imaging modalities, a continuing stage migration towards small, low-grade RCC lesions has become evident during the last decades. Together with this stage migration, nephron-sparing surgery (NSS), less-invasive therapies (laparoscopic RN and NSS), and minimally invasive therapies (radiofrequency ablation [RFA], cryoablation) have been developed and are gaining popularity. The value of laparoscopic RN and open NSS are acknowledged worldwide, but the value of laparoscopic NSS, RFA, and cryoablation remains to be established. Despite this evolution, there is still a place for open surgery for localized RCC. Open NSS is, at present, considered the standard of care for localized RCC less than 4 cm, while open RN still has a place for larger lesions, certainly when an extended lymph node dissection or adrenalectomy is warranted, or when a tumor thrombus is extending into the inferior vena cava. This review provides the data that support open surgery in clear, selected cases of RCC.
Use of Low Molecular Weight Heparin and Aminocaproic Acid in Chronic DIC Associated with Prostate Cancer- A Case Report
Authors: Shirai Keisuke , Chaudhary Uzair B.
Published: June 2007

Disseminated Intravascular Coagulopathy (DIC) is the most common coagulopathy in patients with prostate cancer. Though rare, it could be fatal without treatment. Literature suggests that there is significant activation of fibrinolytic pathway. Pathophysiology of DIC in patients with prostate cancer is not completely understood. We present here a case of chronic DIC in a patient with metastatic androgen independent prostate cancer. His DIC was managed successfully with a combination of aminocaproic acid and low weight molecular heparin. The use of low molecular weight heparin may make management of chronic DIC in prostate cancer more feasible in an out patient setting.
Thermal Ablation of Small Renal Tumors – Present Status
Authors: Lovisolo Jon A. J. , Legramandi Claudio P. , Fonte Aldo
Published: June 2007

Thermal ablation of renal tumors is achieved by the delivery of extreme heat or extreme cold directly to the lesion in order to obtain in situ destruction of the malignant cells without having to remove the entire organ. Cryotherapy and radiofrequency ablation are becoming more and more attractive for the treatment of small lesions in select cases. Other types of energy such as microwave, laser and high intensity ultrasound have also been used to destroy kidney lesions but must still be considered in the experimental stage. Cryotherapy and radiofrequency ablation are minimally invasive and have been shown to be safe and effective in treating tumors up to 3–4 cm in diameter. However, the number of case series is rather limited and follow-up, especially for radiofrequency ablation, is short. Only now are workers beginning to present outcomes after 5 years for cryoablation. Therefore, the long-term oncological efficacy of these ablation techniques remains to be seen. As longer follow-up and greater patient numbers are reported we will get a clearer picture of the true potential of these modalities. Randomized prospective trials would be auspicable. For now, CA and RFA should be limited to few select patients i.e. patients with comorbidities which render them at high risk for a surgical procedure and possibly patients with genetic conditions such as Von Hippel Lindau disease who will probably develop multiple tumors.
Cytoreductive Nephrectomy and Nephrectomy/Complete Metastasectomy for Metastatic Renal Cancer
Authors: Russo Paul , Synder Mark , Vickers Andrew , Kondagunta Varuni , Motzer Robert
Published: June 2007

The objective of this study was to determine our institutional experience with cytoreductive nephrectomy alone or in conjunction with nephrectomy complete metastasectomy. Between July 1989 and September 2003, we queried our department's renal tumor database for patients undergoing cytoreductive nephrectomy alone or in conjunction with complete metastasectomy. Clinical and pathological factors analyzed included primary tumor size, stage and histological subtype, age, gender, Karnofsky Performance Status (KPS) prior to nephrectomy, number and location of metastatic sites, and the presence or absence of any systemic therapy. Preoperative laboratory values analyzed included hemoglobin (HGB), calcium (CA), albumin (ALB), lactose dehydrogenase (LDH), alkaline phosphatase (ALP), and corrected calcium. Corrected calcium was defined as follows: corrected calcium = total calcium - 0.707*(albumin - 3.4). During this time frame, 1628 patients underwent nephrectomy (partial or radical) for renal masses, 91 (5.6%) of whom had metastatic disease. In this group, 71% of patients were male, 88% of patients had a KPS of 80% or greater, and 92% had conventional clear cell histology. Sixty-four percent of patients had a single site of metastatic disease, with lung the most common, followed by bone, adrenal, brain, and liver. Sixty-one patients (67%) had nephrectomy with removal of all metastatic sites (nephrectomy/complete metastasectomy) and 30 (33%) had cytoreductive nephrectomy alone. Median survival for patients undergoing nephrectomy/complete metastasectomy was 30 months. Median survival for patients undergoing cytoreductive nephrectomy alone was 12 months. Perioperative complications occurred in 13% of patients and four patients died within 30 days of their operation. For patients with metastatic renal cell carcinoma, surgical resection of the primary tumor alone (cytoreductive nephrectomy) or in conjunction with metastasectomy can be accomplished with acceptable perioperative morbidity and mortality. This surgical experience provides a contemporary foundation as new targeted therapeutic agents are integrated into the neoadjuvant or adjuvant treatment of locally advanced and metastatic renal cancer.
The Role of Pelvic Lymphadenectomy in the Management of Prostate and Bladder Cancer
Authors: Woods Michael E. , Ouwenga Michael , Quek Marcus L.
Published: June 2007

A pelvic lymph node dissection is commonly performed by urologists in the surgical management of prostate and bladder cancer. Identification of lymph node metastases provides important prognostic information for both diseases. Despite advances in radiographic imaging, a pelvic lymphadenectomy remains the most accurate method to stage lymph node involvement. In the past two decades, there has been an increase in the diagnosis of early stage prostate cancer, which has led some to omit a pelvic lymphadenectomy in patients thought to have low probability of positive lymph nodes. There is little debate, however, over the inclusion of a lymph node dissection in bladder cancer given the approximately 25% incidence of unsuspected nodal disease at the time of surgery. Controversy exists over the extent of an appropriate lymphadenectomy and its therapeutic efficacy. This review will examine the need, extent, and the potential prognostic and therapeutic benefits of a pelvic lymphadenectomy in prostate and bladder cancer.
The Role of Targeted Therapy in Metastatic Renal Cell Carcinoma
Authors: Unnithan Jaya , Rini Brian I.
Published: June 2007

Renal cell carcinoma (RCC) is a highly vascular tumor in which a growing understanding of disease biology has been translated into clinically active systemic therapies. The most clinically developed targeted therapies in advanced RCC are those that target the vascular endothelial growth factor (VEGF) ligand or receptor (VEGFR) and therapy directed against the mammalian target of rapamycin (mTOR). Sutent and sorafenib are orally available inhibitors of the VEGFR and platelet derived growth factor receptor (PDGFR). Temsirolimus is an mTOR inhibitor that leads to G1cell cycle arrest and may affect VEGF production. This article briefly describes the biological pathways involved in the development of RCC and the results of clinical trials using targeted therapy in metastatic RCC.
Botulinum Toxin Use in the Lower Urinary Tract
Authors: Morrisroe Shelby N. , Chancellor Michael B.
Published: June 2007

Botulinum toxins are well known for their ability to disrupt neurotransmission and cause muscle paralysis. Recently, urologists have discovered their beneficial effects in patients with neurogenic and overactive bladder conditions. This review is intended to provide a quick overview for urologists of the structure, function, and clinical uses of botulinum neurotoxin A in the lower urinary tract.
Primary Paratesticular Osteosarcoma: Case Report and A Review of the Literature
Authors: Al-Masri Anwar , Al-Shraim Mubarak , Abu Al-Samen Ahmad , Chetty Runjan , Evans Andrew
Published: June 2007

Primary paratesticular osteosarcoma is an extremely rare malignancy and, to date, only a few cases have been reported. To our knowledge, no such case arising directly from paratesticular soft tissue has been described. We describe a 52-year-old man who presented with left scrotal swelling and an excisional biopsy that revealed a sarcomatous lesion. Left inguinal orchiectomy was performed and histologic examination of the extensively sampled lesion revealed a pure paratesticular osteosarcoma. The patient died 6 months after the diagnosis with disseminated disease.
Gravin regulates mesodermal cell behavior changes required for axis elongation during zebrafish gastrulation
Authors: Weiser Douglas C. , Pyati Ujwal J. , Kimelman David
Published: June 2007

Convergent extension of the mesoderm is the major driving force of vertebrate gastrulation. During this process, mesodermal cells move toward the future dorsal side of the embryo, then radically change behavior as they initiate extension of the body axis. How cells make this transition in behavior is unknown. We have identified the scaffolding protein and tumor suppressor Gravin as a key regulator of this process in zebrafish embryos. We show that Gravin is required for the conversion of mesodermal cells from a highly migratory behavior to the medio-laterally intercalative behavior required for body axis extension. In the absence of Gravin, paraxial mesodermal cells fail to shut down the protrusive activity mediated by the Rho/ROCK/Myosin II pathway, resulting in embryos with severe extension defects. We propose that Gravin functions as an essential scaffold for regulatory proteins that suppress the migratory behavior of the mesoderm during gastrulation, and suggest that this function also explains how Gravin inhibits invasive behaviors in metastatic cells.
Post-translational regulation of the Drosophila circadian clock requires protein phosphatase 1 (PP1)
Authors: Fang Yanshan , Sathyanarayanan Sriram , Sehgal Amita
Published: June 2007

Phosphorylation is an important timekeeping mechanism in the circadian clock that has been closely studied at the level of the kinases involved but may also be tightly controlled by phosphatase action. Here we demonstrate a role for protein phosphatase 1 (PP1) in the regulation of the major timekeeping molecules in the Drosophila clock, TIMELESS (TIM) and PERIOD (PER). Flies with reduced PP1 activity exhibit a lengthened circadian period, reduced amplitude of behavioral rhythms, and an altered response to light that suggests a defect in the rising phase of clock protein expression. On a molecular level, PP1 directly dephosphorylates TIM and stabilizes it in both S2R+ cells and clock neurons. However, PP1 does not act in a simple antagonistic manner to SHAGGY (SGG), the kinase that phosphorylates TIM, because the behavioral phenotypes produced by inhibiting PP1 in flies are different from those achieved by overexpressing SGG. PP1 also acts on PER, and TIM regulates the control of PER by PP1, although it does not affect PP2A action on PER. We propose a modified model for post-translational regulation of the Drosophila clock, in which PP1 is critical for the rhythmic abundance of TIM/PER while PP2A also regulates the nuclear translocation of TIM/PER.
Silencing of xenogeneic DNA by H-NS—facilitation of lateral gene transfer in bacteria by a defense system that recognizes foreign DNA
Authors: Navarre William Wiley , McClelland Michael , Libby Stephen J. , Fang Ferric C.
Published: June 2007

Lateral gene transfer has played a prominent role in bacterial evolution, but the mechanisms allowing bacteria to tolerate the acquisition of foreign DNA have been incompletely defined. Recent studies show that H-NS, an abundant nucleoid-associated protein in enteric bacteria and related species, can recognize and selectively silence the expression of foreign DNA with higher adenine and thymine content relative to the resident genome, a property that has made this molecule an almost universal regulator of virulence determinants in enteric bacteria. These and other recent findings challenge the ideas that curvature is the primary determinant recognized by H-NS and that activation of H-NS-silenced genes in response to environmental conditions occurs through a change in the structure of H-NS itself. Derepression of H-NS-silenced genes can occur at specific promoters by several mechanisms including competition with sequence-specific DNA-binding proteins, thereby enabling the regulated expression of foreign genes. The possibility that microorganisms maintain and exploit their characteristic genomic GC ratios for the purpose of self/non-self-discrimination is discussed.
The Rad9–Hus1–Rad1 (9–1–1) clamp activates checkpoint signaling via TopBP1
Authors: Delacroix Sinny , Wagner Jill M. , Kobayashi Masahiko , Yamamoto Ken-ichi , Karnitz Larry M.
Published: June 2007

DNA replication stress triggers the activation of Checkpoint Kinase 1 (Chk1) in a pathway that requires the independent chromatin loading of the ATRIP–ATR (ATR-interacting protein/ATM [ataxia-telangiectasia mutated]–Rad3-related kinase) complex and the Rad9–Hus1–Rad1 (9–1–1) clamp. We show that Rad9’s role in Chk1 activation is to bind TopBP1, which stimulates ATR-mediated Chk1 phosphorylation via TopBP1’s activation domain (AD), a domain that binds and activates ATR. Notably, fusion of the AD to proliferating cell nuclear antigen (PCNA) or histone H2B bypasses the requirement for the 9–1–1 clamp, indicating that the 9–1–1 clamp’s primary role in activating Chk1 is to localize the AD to a stalled replication fork.
The band mutation in Neurospora crassa is a dominant allele of ras-1 implicating RAS signaling in circadian output
Authors: Belden William J. , Larrondo Luis F. , Froehlich Allan C. , Shi Mi , Chen Chen-Hui , Loros Jennifer J. , Dunlap Jay C.
Published: June 2007

band, an allele enabling clear visualization of circadianly regulated spore formation (conidial banding), has remained an integral tool in the study of circadian rhythms for 40 years. bd was mapped using single-nucleotide polymorphisms (SNPs), cloned, and determined to be a T79I point mutation in ras-1. Alterations in light-regulated gene expression in the ras-1bd mutant suggests that the Neurospora photoreceptor WHITE COLLAR-1 is a target of RAS signaling, and increases in transcription of both wc-1 and fluffy show that regulators of conidiation are elevated in ras-1bd. Comparison of ras-1bd with dominant active and dominant-negative ras-1 mutants and biochemical assays of RAS function indicate that RAS-1bd displays a modest enhancement of GDP/GTP exchange and no change in GTPase activity. Because the circadian clock in ras-1bd appears to be normal, ras-1bd apparently acts to amplify a subtle endogenous clock output signal under standard assay conditions. Reactive oxygen species (ROS), which can affect and be affected by RAS signaling, increase conidiation, suggesting a link between generation of ROS and RAS-1 signaling; surprisingly, however, ROS levels are not elevated in ras-1bd. The data suggest that interconnected RAS- and ROS-responsive signaling pathways regulate the amplitude of circadian- and light-regulated gene expression in Neurospora.
Bone marrow-derived endothelial progenitor cells are a major determinant of nascent tumor neovascularization
Authors: Nolan Daniel J. , Ciarrocchi Alessia , Mellick Albert S. , Jaggi Jaspreet S. , Bambino Kathryn , Gupta Sunita , Heikamp Emily , McDevitt Michael R. , Scheinberg David A. , Benezra Robert , Mittal Vivek
Published: June 2007

Tumors build vessels by cooption of pre-existing vasculature and de novo recruitment of bone marrow (BM)-derived endothelial progenitor cells (EPCs). However, the contribution and the functional role of EPCs in tumor neoangiogenesis are controversial. Therefore, by using genetically marked BM progenitor cells, we demonstrate the precise spatial and temporal contribution of EPCs to the neovascularization of three transplanted and one spontaneous breast tumor in vivo using high-resolution microscopy and flow cytometry. We show that early tumors recruit BM-derived EPCs that differentiate into mature BM-derived endothelial cells (ECs) and luminally incorporate into a subset of sprouting tumor neovessels. Notably, in later tumors, these BM-derived vessels are diluted with non-BM-derived vessels from the periphery, which accounts for purported differences in previously published reports. Furthermore, we show that specific ablation of BM-derived EPCs with α-particle-emitting anti-VE-cadherin antibody markedly impaired tumor growth associated with reduced vascularization. Our results demonstrate that BM-derived EPCs are critical components of the earliest phases of tumor neoangiogenesis.
Resistance to Botrytis cinerea in sitiens, an Abscisic Acid-Deficient Tomato Mutant, Involves Timely Production of Hydrogen Peroxide and Cell Wall Modifications in the Epidermis
Authors: Asselbergh Bob , Curvers Katrien , França Soraya C. , Audenaert Kris , Vuylsteke Marnik , Van Breusegem Frank , Höfte Monica
Published: June 2007

Plant defense mechanisms against necrotrophic pathogens, such as Botrytis cinerea, are considered to be complex and to differ from those that are effective against biotrophs. In the abscisic acid-deficient sitiens tomato (Solanum lycopersicum) mutant, which is highly resistant to B. cinerea, accumulation of hydrogen peroxide (H2O2) was earlier and stronger than in the susceptible wild type at the site of infection. In sitiens, H2O2 accumulation was observed from 4 h postinoculation (hpi), specifically in the leaf epidermal cell walls, where it caused modification by protein cross-linking and incorporation of phenolic compounds. In wild-type tomato plants, H2O2 started to accumulate 24 hpi in the mesophyll layer and was associated with spreading cell death. Transcript-profiling analysis using TOM1 microarrays revealed that defense-related transcript accumulation prior to infection was higher in sitiens than in wild type. Moreover, further elevation of sitiens defense gene expression was stronger than in wild type 8 hpi both in number of genes and in their expression levels and confirmed a role for cell wall modification in the resistant reaction. Although, in general, plant defense-related reactive oxygen species formation facilitates necrotrophic colonization, these data indicate that timely hyperinduction of H2O2-dependent defenses in the epidermal cell wall can effectively block early development of B. cinerea.
SDIR1 Is a RING Finger E3 Ligase That Positively Regulates Stress-Responsive Abscisic Acid Signaling inArabidopsis
Authors: Zhang Yiyue , Yang Chengwei , Li Yin , Zheng Nuoyan , Chen Hao , Zhao Qingzhen , Gao Ting , Guo Huishan , Xie Qi
Published: June 2007

Ubiquitination plays important roles in plant hormone signal transduction. We show that the RING finger E3 ligase, Arabidopsis thaliana SALT- AND DROUGHT-INDUCED RING FINGER1 (SDIR1), is involved in abscisic acid (ABA)-related stress signal transduction. SDIR1 is expressed in all tissues of Arabidopsis and is upregulated by drought and salt stress, but not by ABA. Plants expressing the ProSDIR1–β-glucuronidase (GUS) reporter construct confirmed strong induction of GUS expression in stomatal guard cells and leaf mesophyll cells under drought stress. The green fluorescent protein–SDIR1 fusion protein is colocalized with intracellular membranes. We demonstrate that SDIR1 is an E3 ubiquitin ligase and that the RING finger conservation region is required for its activity. Overexpression of SDIR1 leads to ABA hypersensitivity and ABA-associated phenotypes, such as salt hypersensitivity in germination, enhanced ABA-induced stomatal closing, and enhanced drought tolerance. The expression levels of a number of key ABA and stress marker genes are altered both in SDIR1 overexpression and sdir1-1 mutant plants. Cross-complementation experiments showed that the ABA-INSENSITIVE5 (ABI5), ABRE BINDING FACTOR3 (ABF3), and ABF4 genes can rescue the ABA-insensitive phenotype of the sdir1-1 mutant, whereas SDIR1 could not rescue the abi5-1 mutant. This suggests that SDIR1 acts upstream of those basic leucine zipper family genes. Our results indicate that SDIR1 is a positive regulator of ABA signaling.
An Overview of Essential Hypertension in Americans as a Multifactorial Phenomenon: Interaction of Biologic and Environmental Factors
Authors: Baxendale‐Cox Lynn M.
Published: June 2007

This paper reviews the current literature on essential/primary hypertension in terms of its expression as a multifactorial phenomenon. The genetic and environmental risk factors involved in expression of hypertension and their interactions are discussed. A specific mutation in epithelial sodium channels, T549M, is presented as a genetic risk factor for primary hypertension as expression of this mutation has been reported to result in hyperabsorption of sodium in homozygous individuals. T549M is used in this report to illustrate the multifactorial nature of primary hypertension. Possible interactions of T549M with environmental factors known to promote hypertension and the outcome of these interactions are discussed. Data indicates that both genetic and environmental risk factors must be considered to understand and intervene effectively with patients who have primary or essential hypertension.
Using a Best Practice Approach to Prevent Treatment Interference in Critical Care
Authors: Happ Mary Beth
Published: June 2007

Treatment interference, also known as therapy disruption, device disruption, or self extubation, is a common and especially difficult clinical problem in critical care. This paper presents creative and practical clinical innovations and relevant research findings as a “best practice approach” to prevent treatment interference in critical care settings. Key principles are presented to guide patient assessment and selection of nursing strategies. Nursing assessment parameters are described and a wide range of nonrestraint strategies are discussed.
The Emergency Department Experience of Chest Pain Patients and Their Intention to Delay Care Seeking for Acute Myocardial Infarction
Authors: Meischke Hendrika , Mitchell Paul , Zapka Jane , Goff David C. , Smith Kevin , Henwood Daniel , Mann Clay , Lovell Kathleen , Stone Elaine , Taylor Judy
Published: June 2007

This study investigated how patients' emergency department experience was related to their intention to delay action in response to future symptoms of acute myocardial infarction. A sample of 426 persons admitted to the emergency department with a chief complaint of chest pain and released from the emergency department were contacted by telephone. Patients were queried about their affective response to the emergency department experience, their satisfaction with emergency department staff communication, their intention to delay prompt action for acute myocardial infarction symptoms in the future, the influence of others in the decision to seek care, and medical and demographic status. The results of a mixed model linear regression analysis showed that the less education patients had (p=0.007), the less sure they felt that going to the emergency department had been “the right thing to do” (p=0.004), and the greater the degree of embarrassment (p=0.0001), the greater was the intention to delay action for future symptoms of acute myocardial infarction. The results also showed that those patients who were prompted by health professionals to go to the emergency department were less likely to report intentions to delay for future symptoms (p=0.036). It is important that emergency department staff reassure chest pain patients who are sent home that they did the right thing by coming to the emergency department for their symptoms. Providers need to be particularly sensitive to feelings of embarrassment.
Heart Failure in Women
Authors: Halm Margo A. , Penque Sue
Published: June 2007

Heart failure affects more than 5 million Americans. Each year, about 400,000 individuals develop heart failure, making it the nation's most rapidly growing cardiac problem. Almost one third of these individuals have New York Heart Association Functional Class III or IV heart failure and are faced with progressive clinical deterioration and frequent hospital admissions. These figures will continue to escalate as the population ages. The success of interventional procedures and pharmacologic therapies in the management of coronary artery disease has enabled this population to survive acute events, at the same time creating a population with chronic disease. Common etiologies of heart failure in women include coronary artery disease, myocardial infarction, and valvular disease. However, women are at especially high risk for developing heart failure due to diastolic dysfunction associated with hypertension and diabetes. Heart failure in women is best managed across the care continuum, incorporating pharmacologic agents, interventional procedures when appropriate, dietary restrictions, self‐monitoring, and psychosocial support. Much of the recent literature has focused on women and heart disease. This emphasis is partly due to public misconception about women's health problems and the growing body of research distinguishing gender differences. Significant advances in therapy have been made to improve the quality and span of life for people with heart disease. Despite therapeutic advances, however, women have high mortality rates from heart disease, including heart failure due to ischemic causes. In fact, women with heart failure present differently than men and have different etiologies and treatment options. As we learn more about women and heart disease, the distinguishing differences unfold and become helpful in establishing a plan of care.
Optimum Bedside Cardiac Monitoring
Authors: Jacobson Carol
Published: June 2007

Correct electrode placement is critical to obtaining accurate information from any monitoring lead. The choice of lead should be based on the goals of monitoring for a specific patient population and on the individual patient's clinical situation. When using a 5‐wire monitoring cable, arm electrodes should be placed on the shoulders; leg electrodes, on the lower thorax or hip area; and the chest electrode, in the desired V lead position. When using a 3‐wire system, lead placement depends on which lead is desired for monitoring. If arrhythmia diagnosis is the goal of monitoring, lead V1 is the best lead; lead V6 is the next best lead. If ST segment monitoring for ischemia or reocclusion following percutaneous coronary interventions is the goal, the best lead depends on the coronary artery involved. Multiple lead monitoring is superior to single lead monitoring. If two leads are available, V1 and lead III or aVF (or a limb lead with maximal ST segment displacement) are good choices. If three leads are available, leads V1, III, and aVF are the best choices. Continuous 12‐lead monitoring is available and offers several advantages.
The Role of the Nurse in Enhancing Quality of Life in Patients With an Implantable Cardioverter‐Defibrillator: The Swedish Experience
Authors: Carlsson Eva , Olsson S. Bertil , Hertervig Eva
Published: June 2007

During the last 10–15 years, the implantable cardioverter‐defibrillator (ICD) has become an important mode of treatment for patients suffering from grave ventricular arrhythmias, but ICD implantation involves psychosocial adjustments for both patients and relatives. The aim of this pilot study was to design a plan of education and to follow a selected group of patients with interviews, observations, and a questionnaire. The goals included seeing how well they accepted their situation after the operation when they had ongoing support of the nurse, in comparison to a control group who received conventional patient education by the physician. The patients were randomly allocated into two groups. Twenty patients were recruited, 10 in the study group and 10 in the control group, between February, 1997 and April, 1998. There were 16 men (average age, 63) and four women (average age, 57). The Nottingham Health Profile was used to measure health‐related quality of life. Sleep disturbances were the greatest problem in both the study group and the control group before ICD implantation. In the study group, there was a significant improvement (p<0.05) after ICD implantation in four patients. The study also revealed a difference between men and women, with women having more sleep disturbances before ICD implantation than men (p<0.05). In both groups, there was a lack of energy and emotional reactions, both before and after ICD implantation. Few considered family life a problem before or after the study. In the control group, the patients missed the lack of contact with health care personnel more than in the study group. There was also a greater need for group meetings after the hospital stay. By means of the questionnaire, interviews, and observations, it became evident that there was a great need for information, and a plan of patient education in addition to follow‐up by the nurse was felt to be very important.
Current Options in the Diagnosis and Management of Acute Limb Ischemia
Authors: Kasirajan Karthikeshwar , Ouriel Kenneth
Published: June 2007

Acute limb ischemia occurs due to a sudden decrease in the blood flow to a limb, resulting in a potential threat to the viability of the extremity. Unfortunately, the threat is not only to the limb, but these patients are also at high risk for death. Limb hypoperfusion results in systemic acid‐base and electrolyte abnormalities that impair cardiopulmonary and renal function. Successful reperfusion may result in the release of highly toxic free radicals, further compromising these critically ill patients. Therapeutic choices are often few and patient expectations are not always realistic. The management of acute limb ischemia requires a thorough understanding of the anatomy of the arterial occlusion and the open surgical and percutaneous options for restoring limb perfusion. Priorities for the diagnosis and effective management of these critically ill patients are provided.