bluuebunny/crossref_metadata_2025 huggingface dataset:
Time course study of oxidative and nitrosative stress and antioxidant enzymes in K2Cr2O7-induced nephrotoxicity
Authors: Pedraza-Chaverrí José , Barrera Diana , Medina-Campos Omar N , Carvajal Raymundo C , Hernández-Pando Rogelio , Macías-Ruvalcaba Norma A , Maldonado Perla D , Salcedo Marcos I , Tapia Edilia , Saldívar Liliana , Castilla María E , Ibarra-Rubio María E
Published: April 2005

Background

Potassium dichromate (K2Cr2O7)-induced nephrotoxicity is associated with oxidative and nitrosative stress. In this study we investigated the relation between the time course of the oxidative and nitrosative stress with kidney damage and alterations in the following antioxidant enzymes: Cu, Zn superoxide dismutase (Cu, Zn-SOD), Mn-SOD, glutathione peroxidase (GPx), glutathione reductase (GR), and catalase (CAT).

Methods

Nephrotoxicity was induced in rats by a single injection of K2Cr2O7. Groups of animals were sacrificed on days 1,2,3,4,6,8,10, and 12. Nephrotoxicity was evaluated by histological studies and by measuring creatinine clearance, serum creatinine, blood urea nitrogen (BUN), and urinary excretion of N-acetyl-β-D-glucosaminidase (NAG) and total protein. Oxidative and nitrosative stress were measured by immunohistochemical localization of protein carbonyls and 3-nitrotyrosine, respectively. Cu, Zn-SOD, Mn-SOD, and CAT were studied by immunohistochemical localization. The activity of total SOD, CAT, GPx, and GR was also measured as well as serum and kidney content of chromium and urinary excretion of NO2-/NO3-. Data were compared by two-way analysis of variance followed by a post hoc test.

Results

Serum and kidney chromium content increased reaching the highest value on day 1. Nephrotoxicity was made evident by the decrease in creatinine clearance (days 1–4) and by the increase in serum creatinine (days 1–4), BUN (days 1–6), urinary excretion of NAG (days 1–4), and total protein (day 1–6) and by the structural damage to the proximal tubules (days 1–6). Oxidative and nitrosative stress were clearly evident on days 1–8. Urinary excretion of NO2-/NO3- decreased on days 2–6. Mn-SOD and Cu, Zn-SOD, estimated by immunohistochemistry, and total SOD activity remained unchanged. Activity of GPx decreased on days 3–12 and those of GR and CAT on days 2–10. Similar findings were observed by immunohistochemistry of CAT.

Conclusion

These data show the association between oxidative and nitrosative stress with functional and structural renal damage induced by K2Cr2O7. Renal antioxidant enzymes were regulated differentially and were not closely associated with oxidative or nitrosative stress or with kidney damage. In addition, the decrease in the urinary excretion of NO2-/NO3- was associated with the renal nitrosative stress suggesting that nitric oxide was derived to the formation of reactive nitrogen species involved in protein nitration.
Identification of children who may benefit from self-hypnosis at a pediatric pulmonary center
Authors: Anbar Ran D , Geisler Susan C
Published: April 2005

Background

Emotional difficulties can trigger respiratory symptoms. Thus, children presenting with respiratory complaints may benefit from a psychological intervention. The purpose of this study was to define the proportion of patients referred to a Pediatric Pulmonary Center who may benefit from instruction in self-hypnosis, as a psychological intervention.

Methods

A retrospective chart review was conducted for all newly referred patients to the SUNY Upstate Medical University Pediatric Pulmonary Center during an 18 month period beginning January 1, 2000. Patients were offered hypnosis if they presented with symptoms or signs suggestive of psychological difficulties. Hypnosis was taught in one or two 15–45 minute sessions by a pediatric pulmonologist.

Results

Of 725 new referrals, 424 were 0–5 years old, 193 were 6–11 years old, and 108 were 12–18 years old. Diagnoses of anxiety, habit cough, or vocal cord dysfunction accounted for 1% of the 0–5 year olds, 20% of the 6–11 year olds, and 31% of the 12–18 year olds. Hypnotherapy was offered to 1% of 0–5 year olds, 36% of 6–11 year olds, and 55% of 12–18 year olds. Of 81 patients who received instruction in self-hypnosis for anxiety, cough, chest pain, dyspnea, or inspiratory difficulties, 75% returned for follow-up, and among the returning patients 95% reported improvement or resolution of their symptoms.

Conclusion

A large number of patients referred to a Pediatric Pulmonary Center appeared to benefit from instruction in self-hypnosis, which can be taught easily as a psychological intervention.
The effect of glucosamine sulphate on osteoarthritis: design of a long-term randomised clinical trial [ISRCTN54513166]
Authors: Rozendaal Rianne M , Koes Bart W , Weinans Harrie , Uitterlinden Elian J , van Osch Gerjo JVM , Ginai Abida Z , Verhaar Jan AN , Bierma-Zeinstra Sita MA
Published: April 2005

Background

Pharmacological treatment for osteoarthritis (OA) can be divided into two groups: symptom-modifying drugs and disease-modifying drugs. Symptom-modifying drugs are currently the prescription of choice for patients with OA, as disease-modifying drugs are not yet available in usual care. However, there has recently been a lot of debate about glucosamine sulphate (GS), a biological agent that is thought to have both symptom-modifying and disease-modifying properties. This assumption has yet to be proved.

The objective of this article is to present the design of a blind randomised clinical trial that examines the long-term symptom-modifying and disease-modifying effectiveness of GS in patients with hip OA. This trial is ongoing and will finish in March 2006.

Methods/design

Patients with hip OA meeting the ACR-criteria are randomly allocated to either 1500 mg of oral GS or placebo for the duration of two years. The primary outcome measures, which are joint space narrowing (JSN), and change in the pain and function score of the Western Ontario McMaster Universities Osteoarthritis index (WOMAC), are determined at baseline and after two years of follow-up during the final assessment. Intermediate measures at three-month intervals throughout the trial are used to study secondary outcome measures. Secondary outcome measures are changes in WOMAC stiffness score, quality of life, medical consumption, side effects and differences in biomarker CTX-II.
Promiscuous drugs compared to selective drugs (promiscuity can be a virtue)
Authors: Mencher Simon K , Wang Long G
Published: April 2005

Background

The word selectivity describes a drug's ability to affect a particular cell population in preference to others. As part of the current state of art in the search for new therapeutic agents, the property of selectivity is a mode of action thought to have a high degree of desirability. Consequently there is a growing activity in this area of research.

Selectivity is generally a worthy property in a drug because a drug having high selectivity may have a dramatic effect when there is a single agent that can be targeted against the appropriate molecular-driver involved in the pathogenesis of a disease. An example is chronic myeloid leukemia (CML). CML has a specific chromosomal abnormality, the Philadelphia chromosome, that results in a single gene that produces an abnormal protein

Discussion

There is a burgeoning understanding of the cellular mechanisms that control the etiology and pathogeneses of diseases. This understanding both enables and motivates the development of drugs that induce a specific action in a selected cell population; i.e., a targeted treatment. Consequently, drugs that can target distinct molecular targets involved in pathologic/pathogenetic processes, or signal-transduction pathways, are being developed.

However, in most cases, diseases involve multiple abnormalities. A disease may be associated with more than one dysfunctional protein and these may be out-of-balance with each other. Likewise a drug might strongly target a protein that shares a similar active domain with other proteins. A drug may also target pleiotropic cytokines, or other proteins that have multi-physiological functions. In this way multiple normal cellular pathways can be simultaneously influenced. Long term experience with drugs supposedly designed for only a single target, but which unavoidably involve other functional effects, is uncovering the fact that molecular targeting is not medically flawless.

We contend that an ideal drug may be one whose efficacy is based not on the inhibition of a single target, but rather on the rebalancing of the several proteins or events, that contribute to the etiology, pathogeneses, and progression of diseases, i.e., in effect a promiscuous drug. Ideally, if this could be done at minimum drug concentration, side effects could be minimized. Corollaries to this argument are that the growing fervor for researching truly selective drugs may be imprudent when considering the totality of responses; and that the expensive screening techniques used to discover these, may be both medically and financially inefficient.
Good governance and good health: The role of societal structures in the human immunodeficiency virus pandemic
Authors: Menon-Johansson Anatole S
Published: April 2005

Background

Only governments sensitive to the demands of their citizens appropriately respond to needs of their nation. Based on Professor Amartya Sen's analysis of the link between famine and democracy, the following null hypothesis was tested: "Human Immunodeficiency Virus (HIV) prevalence is not associated with governance".

Methods

Governance has been divided by a recent World Bank paper into six dimensions. These include Voice and Accountability, Political Stability and Absence of Violence, Government Effectiveness, Regulatory Quality, Rule of Law and the Control of Corruption. The 2002 adult HIV prevalence estimates were obtained from UNAIDS. Additional health and economic variables were collected from multiple sources to illustrate the development needs of countries.

Results

The null hypothesis was rejected for each dimension of governance for all 149 countries with UNAIDS HIV prevalence estimates. When these nations were divided into three groups, the median (range) HIV prevalence estimates remained constant at 0.7% (0.05 – 33.7%) and 0.75% (0.05% – 33.4%) for the lower and middle mean governance groups respectively despite improvements in other health and economic indices. The median HIV prevalence estimates in the higher mean governance group was 0.2% (0.05 – 38.8%).

Conclusion

HIV prevalence is significantly associated with poor governance. International public health programs need to address societal structures in order to create strong foundations upon which effective healthcare interventions can be implemented.
Fluorescent proteins as tools to aid protein production
Authors: Su Wei Wen
Published: April 2005

Fluorescent proteins are genetically encoded, highly versatile reporters useful for monitoring various aspects of recombinant protein production. In addition to the widely popular green fluorescent protein (GFP) from Aequorea victoria, a variety of other fluorescent proteins have been discovered that display a wide range of spectral properties. Synthetic variants have also been developed to overcome limitations associated with their wild-type counterparts. Having a large repertoire of fluorescent proteins with diverse traits opens new opportunities for rapid monitoring and optimization of recombinant protein production.
The role of mutation in the new cancer paradigm
Authors: Prehn Richmond T
Published: April 2005

The almost universal belief that cancer is caused by mutation may gradually be giving way to the belief that cancer begins as a cellular adaptation that involves the local epigenetic silencing of various genes. In my own interpretation of the new epigenetic paradigm, the genes epigenetically suppressed are genes that normally serve in post-embryonic life to suppress and keep suppressed those other genes upon which embryonic development depends. Those other genes, if not silenced or suppressed in the post-embryonic animal, become, I suggest, the oncogenes that are the basis of neoplasia.

Mutations that occur in silenced genes supposedly go unrepaired and are, therefore, postulated to accumulate, but such mutations probably play little or no causative role in neoplasia because they occur in already epigenetically silenced genes. These mutations probably often serve to make the silencing, and therefore the cancer, epigenetically irreversible.
Prevalence and burden of self-reported blindness and low vision for individuals living in institutions: a nationwide survey
Authors: Brézin Antoine Pierre , Lafuma Antoine , Fagnani Francis , Mesbah Mounir , Berdeaux Gilles
Published: April 2005

Background

The prevalence of self-reported low vision (LV) and blindness, and their associated disabilities, handicaps and socio-economic consequences for individuals living in institutions are poorly documented.

Methods

2,075 institutions were selected at random and eight individuals were picked at random from the list of residents. Three groups of individuals were defined: blind, LV, and a control group (CG). These were compared after adjustment for age and co-morbidities. Of the 15,403 individuals, 14,603 interviews (94.9%) were completed.

Results

The prevalence of blindness was 1.6% and the LV 13.4%. Blind individuals needed assistance more often (OR: 2.65 to 11.35) than CG members while the assistance required by LV individuals was similar to that for the CG. Blind individuals required institution adaptation (building and furniture changes) more often than the CG. Blind (57.9%) and LV individuals (35.4%) were more often registered for social allowances. Monthly social allowances were EUR 86 higher for blind than LV individuals. Monthly family incomes were found to be similar between the three groups (from EUR 782 to 797). Social and demographic data, institution description, income, handicaps, disabilities, social allowances and details of daily activities were collected interviews

Conclusion

The results demonstrate the impact of self-reported blindness and LV on daily life for patients living in institutions.
Decreased levels of soluble receptor for advanced glycation end products in patients with rheumatoid arthritis indicating deficient inflammatory control
Authors: Pullerits Rille , Bokarewa Maria , Dahlberg Leif , Tarkowski Andrej
Published: April 2005

The receptor for advanced glycation end products (RAGE) is a member of the immunoglobulin superfamily being expressed as a cell surface molecule and binding a variety of ligands. One of these ligands is high-mobility group box chromosomal protein 1, a potent proinflammatory cytokine, expression of which is increased in synovial tissue and in synovial fluid of rheumatoid arthritis (RA) patients. The interaction of high-mobility group box chromosomal protein 1 with cell-surface RAGE leads to an inflammatory response. In contrast, the presence of soluble RAGE (sRAGE) may abrogate cellular activation since the ligand is bound prior to interaction with the surface receptor.

Our aim was to analyse to what extent sRAGE is present in patients with chronic joint inflammation (RA) as compared with patients with non-inflammatory joint disease and with healthy subjects, and to assess whether there is an association between sRAGE levels and disease characteristics.

Matching samples of blood and synovial fluid were collected from 62 patients with RA with acute joint effusion. Blood from 45 healthy individuals, synovial fluid samples from 33 patients with non-inflammatory joint diseases and blood from six patients with non-inflammatory joint diseases were used for comparison. sRAGE levels were analysed using an ELISA.

RA patients displayed significantly decreased blood levels of sRAGE (871 ± 66 pg/ml, P < 0.0001) as compared with healthy controls (1290 ± 78 pg/ml) and with patients with non-inflammatory joint disease (1569 ± 168 pg/ml). Importantly, sRAGE levels in the synovial fluid of RA patients (379 ± 36 pg/ml) were lower than in corresponding blood samples and correlated significantly with blood sRAGE. Interestingly, a significantly higher sRAGE level was found in synovial fluid of RA patients treated with methotrexate as compared with patients without disease-modifying anti-rheumatic treatment.

We conclude that a decreased level of sRAGE in patients with RA might increase the propensity towards inflammation, whereas treatment with methotrexate counteracts this feature.
Utilization of rapid-infuser devices for massive blood loss
Authors: Stammers Alfred H , Murdock James D , Klayman Myra H , Trowbridge Cody , Yen Bianca R , Franklin David , Elmore James
Published: April 2005

Rapid volume replacement for severe hemorrhage continues to challenge the clinician involved in the care of the patient suffering hemorrhagic shock. We report on the development and utilization of two rapid-infuser systems for volume replacement in critically ill patients presenting in extremis.

We have developed rapid-infusion circuits by using commercially available devices available at our institution. The primary pumping mechanism is either a centrifugal pump (Revolution™COBE Cardiovascular, Arvada, CO, USA), or the Myocar-dial Protection System (MPS™ - Quest Medical, Allen, TX, USA), and offers advantages over commercially available devices. Both circuits consist of a cardiotomy reservoir, a cardioplegia delivery set, assorted tubing and connectors, and a heater-cooler system.

Between January and October of 2003, 15 procedures were performed which utilized one of these two devices. There were nine ruptured aneurysms, five traumas and one radical nephrectomy. The rapid infusion time averaged 228.59±105.7 min where 10.49±9.4 L of autotransfusion volume was processed, with 3.99±4.2 L of red cell volume reinfused. The allogeneic blood products that were transfused included packed red blood cells and fresh frozen plasma, as well as 5% albumin. There were no intraoperative deaths and the rapid-infuser was considered lifesaving in all instances.

Mechanical rapid infusion systems may be lifesaving when severe hypovolemia or hemorrhagic shock is encountered. While both devices are able to meet the requirements of rapid fluid replacement, the MPS offers the most safety features and has become the standard of care at our institution.
Dextran sulfate as a leukocyte-endothelium adhesion molecule inhibitor of lung injury in pediatric open-heart surgery
Authors: Komai Hiroyoshi , Naito Yasuaki , Okamura Yoshitaka
Published: April 2005

Background: In spite of the progress in operative techniques and pre- and postoperative management for congenital heart disease, lung injury induced by the extracorporeal circulation is still a serious insult in pediatric open-heart operations. To prevent this injury, we used a leukocyte - endothelial cell adhesion molecule blocking agent, dextran sulfate, in a clinical setting.

Methods: Sixty mg/kg of dextran sulfate (DS) was intravenously infused to the patients just before cardio-pulmonary bypass was started and 600 mg was added to the bypass circuit prime. Thirty patients (DS group, 14 patients with atrial septal defect, and 16 patients with ventricular septal defect) were compared with age and body-weight matched control patients (control group, 14 patients with atrial septal defect, 11 patients with ventricular septal defect). Postoperative respiratory index, white blood cell counts, complement C3 and plasma granulocyte elastase levels during and after the operation were measured.

Results: Respiratory index just after the termination of cardiopulmonary bypass was better preserved in the DS group than in the control group (0.50±0.08 versus 0.81±0.12, p<0.01). The sum total amount of measured granulocyte elastase across whole study period was significantly lower in the DS group ( p<0.05).

Conclusions: The data suggested the possible effects of dextran sulfate in ameliorating post-perfusion lung damage by interfering with leukocyte-endothelial cell adhesion in pediatric open-heart operations. Future application to patients with more complex anomalies is anticipated.
Construction of a pulmonary artery pump for unifocalization and repair of pulmonary atresia with ventricular septal defect and major aortopulmonary collaterals
Authors: Haga-Greco Tammy M , Niimi Kevin S
Published: April 2005

Single-stage repair has been presented as the treatment of choice for pulmonary atresia with ventricular septal defect and major aortopulmonary collaterals. This surgical approach may result in the difficult decision of whether to close the ventricular septal defect. This decision may significantly affect the postoperative course of the patient. There are several diagnostic techniques clinicians may use to help them decide if closure is indicated. One technique is to modify an extracorporeal circuit to deliver precise flow rates of blood into the newly created pulmonary arterial system, at the same time supporting the patient during the operative procedure. While this technique is not novel, there is only a single published description of the circuit. This report is brief and does not discuss potential complications that these modifications may cause. Therefore, it is the purpose of this paper to describe a circuit modification to perform this diagnostic measurement as well as elucidating potential risks of this technique.
Coagulation management of a patient with factor V Leiden mutation, lupus anticoagulant, and activated protein C resistance: a case report
Authors: Stammers Alfred H , Dorion R Patrick , Trowbridge Cody , Yen Bianca , Klayman Myra , Murdock James D , Woods Edward , Gilbert Christian
Published: April 2005

Although patients undergoing cardiac surgery often present with diverse comorbidities, those with coagulation derangements are especially challenging. The present report describes the management of a patient who presented with a Factor V Leiden mutation, lupus anticoagulant, and acquired activated protein C resistance.

A 42-year-old female presented with acute shortness of breath and chest pain. She was otherwise healthy 1 month prior to admission when she presented with dysfunctional uterine bleeding, resulting in the transfusion of three units of packed red blood cells. Coagulation evaluation revealed that the patient had lupus anticoagulant, factor V Leiden mutation and an activated protein C resistance. The patient presented with an acute myocardial infarction and was found to have 90% stenosis of her left main coronary artery, moderate mitral and tricuspid regurgitation, and a left ventricular ejection fraction of 25%. An emergent off-pump coronary artery bypass procedure with placement of a vein graft to the left anterior descending artery was completed. Intraoperative thrombophilia was encountered as evidenced by both an elevated thromboelastograph™ coagulation index (=3.6) and an acquired antithrombin-III deficiency. Postoperatively, the patient was placed on low molecular weight heparin, but developed heparin-induced thrombocytopenia and was switched to a direct thrombin inhibitor, argatroban.

The following case report describes the coagulation management of this patient from the time of admission to discharge 43 days later, and the unique challenges this combination of hemostatic defects present to the clinicians.
Pulmonary thromboendarterectomy for chronic thromboembolic pulmonary hypertension
Authors: Puis Luc , Vandezande Eddy , Vercaemst Leen , Janssens Patrick , Taverniers Yvan , Foulon Mark , Demeyere Roland , Delcroix Marion , Daenen Willem
Published: April 2005

Introduction. Pulmonary thromboendarterectomy (PTE) is a surgical procedure which is considered the only effective and potentially curative treatment for chronic thromboembolic pulmonary hypertension (CTEPH). CTEPH is a rare outcome from pulmonary emboli and, when left untreated, will result in right ventricular failure and death.

Methods. From June 1999 to November 2003, 40 of these procedures were performed in our institution. Emphasis is placed on multidisciplinarity and cooperation between different medical and surgical disciplines. Perfusion management consists of myocar-dial and cerebral protection, deep hypothermia with multiple periods of circulatory arrest, reperfusion at hypothermia, hemofiltration and cellsaving techniques.

Results. Hemodynamic improvement occurs immediately post operation. Mean pulmonary artery pressure decreased from 50±11 to 38±10 mmHg, pulmonary vascular resistance from 1246±482 to 515±294 dynes s/cm5 and cardiac index increased from 1.54±0.54 to 2.63±0.75 L/min per m2. Pump runs had an average duration of 187±29 min, circulatory arrest time was 29±11 min and crossclamp time 36±14 min. Extracorporeal membrane oxygenation can be an ultimate treatment for specific postoperative problems like persistent pulmonary hypertension and/or reperfusion pulmonary edema.
Inflammatory cytokine inhibition of erythropoiesis in patients implanted with a mechanical circulatory assist device
Authors: Pierce Christopher N , Larson Douglas F
Published: April 2005

Mechanical circulatory assist devices (MCADs) are increasingly utilized independently of cardiac transplantation in the management of heart failure. Though MCAD use incorporates inherent mechanical risks, the inevitable onset of chronic anemia, with its associated morbidity and mortality, is also a significant concern. MCAD support has been correlated with elevated plasma levels of inflammatory cytokines TNF-α, IL-1b, and IL-6, which have separately been found to inhibit erythropoietin (Epo)-induced erythrocyte (RBC) maturation. Previous analysis of hematological parameters for MCAD-sup-ported patients concluded that an amplified inflammatory response impedes RBC proliferation and recovery from hemolytic anemia. Additional analysis may bolster this assertion. Hemoglobin concentration (HC), RBC distribution width (RDW), mean cell volume (MCV), and cardiac index were retrospectively analysed for 78 MCAD-supported patients implanted for greater than 30 days at the University of Arizona Health Sciences Center from 1996 to 2002. Analysis confirms that the HC, a conventional marker for anemia, declines with MCAD placement and remains below the clinically defined, minimum normal value. Inversely, the RDW rises above maximum normal measure, signifying an increased fraction of juvenile RBCs. The MCV remains unchanged and within normal limits, demonstrating adequate substrate for RBC formation. MCAD performance also stabilizes as adequate perfusion returns. These results further support our previously published conclusion that a sufficient response of erythropoiesis occurs in reaction to the onset of anemia by an increased production of immature RBCs. However, the cells never fully mature and join circulation. The patient’s inflammatory cytokine response to the implanted device most likely mediates the chronic MCAD-induced anemia by inhibition of Epo effects.
Evaluation of a new condensed extra-corporeal circuit for cardiac surgery: a prospective randomized clinical pilot study
Authors: Fransen Erik J , Ganushchak Yuri M , Vijay Ventakaramana , de Jong Dick S , Buurman Wim A , Maessen Jos G
Published: April 2005

This prospective randomized clinical pilot study was conducted to evaluate a recently introduced reduced volume CPB system that is coated with the biopassive Xcoating™. Twenty-two patients undergoing coronary artery bypass grafting (CABG) with cardiopulmonary bypass (CPB), either with a fully heparin-coated CPB circuit (control, n=11) or with an Xcoating™ coated condensed extra-corporeal circuit (CondECC, n=11), were included.

We examined activation of the complement system (C3bc and C4bc), activation of neutrophils (BPI), the acute phase response (interleukin (IL)-6, and acute phase proteins (LBP, AGP, and CRP)), myocardial tissue injury (troponin T), hemolysis (free hemoglobin (FHb)), and clinical outcome parameters. Preoperative risk profiles were identical for both patient groups. All patients went through the procedure without major complications and were discharged from the hospital. FHb and BPI levels at the end of pump support ( p <0.01) and at 15 min after the administration of protamine ( p <0.05) were significantly higher in the control group. In addition, FHb levels were still significantly elevated upon arrival on the cardiothoracic intensive care unit (CICU) in the control group ( p <0.05). C3bc and C4bc, acute phase proteins, IL-6, and troponin T concentrations, and clinical outcome variables were identical in both patient groups.

In conclusion, the evaluated condensed extracorporeal circuit is a flexible and multifunctional CPB sytem that offers safe procedures. Furthermore, the results indicate improved biocompatibility of this option for extracorporeal circulation.
Microsurgical Anatomy of the Dural Arteries
Authors: Martins Carolina , Yasuda Alexandre , Campero Alvaro , Ulm Arthur J. , Tanriover Necmettin , Rhoton Albert
Published: April 2005

OBJECTIVE:

The objective was to examine the microsurgical anatomy basic to the microsurgical and endovascular management of lesions involving the dural arteries.

METHODS:

Adult cadaveric heads and skulls were examined using the magnification provided by the surgical microscope to define the origin, course, and distribution of the individual dural arteries.

RESULTS:

The pattern of arterial supply of the dura covering the cranial base is more complex than over the cerebral convexity. The internal carotid system supplies the midline dura of the anterior and middle fossae and the anterior limit of the posterior fossa; the external carotid system supplies the lateral segment of the three cranial fossae; and the vertebrobasilar system supplies the midline structures of the posterior fossa and the area of the foramen magnum. Dural territories often have overlapping supply from several sources. Areas supplied from several overlapping sources are the parasellar dura, tentorium, and falx. The tentorium and falx also receive a contribution from the cerebral arteries, making these structures an anastomotic pathway between the dural and parenchymal arteries. A reciprocal relationship, in which the territories of one artery expand if the adjacent arteries are small, is common.

CONCLUSION:

The carotid and vertebrobasilar arterial systems give rise to multiple branches that supply the dura in a complex and overlapping pattern. A knowledge of the microsurgical anatomy of these dural arteries and their assessment on pretreatment evaluations plays a major role in safe and accurate treatment of multiple lesions.
Combination of Functional Magnetic Resonance Imaging-guided Neuronavigation and Intraoperative Cortical Brain Mapping Improves Targeting of Motor Cortex Stimulation in Neuropathic Pain
Authors: Pirotte Benoit , Voordecker Philippe , Neugroschl Carine , Baleriaux Danielle , Wikler David , Metens Thierry , Denolin Vincent , Joffroy Alfred , Massager Nicolas , Brotchi Jacques , Levivier Marc
Published: April 2005

OBJECTIVE:

To evaluate, regardless of the clinical results, the contribution of combining functional magnetic resonance imaging (fMRI) with intraoperative cortical brain mapping (iCM) as functional targeting methods for epidural chronic motor cortex stimulation (MCS) in refractory neuropathic pain.

METHODS:

Eighteen neuropathic pain patients (central stroke in six; trigeminal neuropathy in six; syrinx or amputation in six) who underwent operations for epidural MCS were studied with preoperative fMRI and iCM. fMRI investigated motor tasks of hands (as well as foot and tongue, when painful). fMRI data were analyzed with Statistical Parametric Mapping99 software (University College London, London, England; initial analysis threshold corresponding to P < 0.001), registered in a neuronavigation system, and correlated during surgery with iCM. The primary aim of this study was to improve the topographical precision of MCS. Matching of fMRI and iCM specifically was examined.

RESULTS:

Correspondence between the contour of the fMRI activation area and iCM in precentral gyrus (mean distance, 3.8 mm) was found in 17 (94%) of 18 patients. Eleven of them showed correspondence for more restrictive values of the analysis threshold (P < 0.0001); in six patients, the quality of the iCM was reduced by somatosensory wave attenuation and general anesthesia. In this group of six patients, a combination of both techniques was used for the final targeting. Correspondence was not found in one patient as the result of image distortion and residual motion artifact. At follow-up (4–60 mo), MCS induced significant pain relief in a total of 11 patients (61%).

CONCLUSION:

This study confirms the functional accuracy of fMRI guidance in neuropathic pain and illustrates the usefulness of combining fMRI guidance with iCM to improve the functional targeting in MCS. Because appropriate targeting is crucial to obtaining pain relief, this combination may increase the analgesic efficacy of MCS.
Comparison of Three Methods of Targeting the Subthalamic Nucleus for Chronic Stimulation in Parkinson's Disease
Authors: Andrade-Souza Yuri M. , Schwalb Jason M. , Hamani Clement , Eltahawy Hazem , Hoque Tasnuva , Saint-Cyr Jean , Lozano Andres M.
Published: April 2005

OBJECTIVE:

The success of subthalamic nucleus (STN) surgery for Parkinson's disease depends on accuracy in target determination. The objective of this study was to determine which of the following techniques was most accurate and precise in identifying the location for stimulation in STN deep brain stimulation surgery that is most clinically effective: direct targeting, indirect targeting using the positions of the anterior and posterior commissures, or a technique using the red nucleus (RN) as an internal fiducial marker.

METHODS:

We reviewed 14 patients with Parkinson's disease treated with bilateral STN deep brain stimulation (28 STN targets). Electrode implantation was based on direct and indirect targeting using two-dimensional magnetic resonance imaging with refinement using microelectrode recording. Optimal settings, including the contacts used, were determined during the clinical follow-up. The position of the best contact was defined with postoperative magnetic resonance imaging. This location was compared with the modified direct, indirect, and RN-based targets. The mean distances between the targets and the final position of the optimal contact were calculated. The accuracy and variance of each target were analyzed.

RESULTS:

The mean position of the best contact was x = 12.12 (standard deviation [SD], 1.45 mm), y = −2.41 (SD, 1.63 mm), and z = −2.39 (SD, 1.49 mm) relative to the midcommissural point. The mean distance between the optimal contact position and the planned target was 3.19 mm (SD, 1.19 mm) using the RN-based method, 3.42 mm (SD, 1.34 mm) using indirect targeting, and 4.66 mm (SD, 1.33 mm) using a modified direct target. The mean distance between the optimal contact and the RN-based target was significantly smaller than the mean distance between the optimal contact and the direct target (post hoc with Tamhane's correction, P < 0.001) but not between the optimal contact and the indirect target. The RN-based target had the smallest variance (F test, P < 0.001), indicating greater precision.

CONCLUSION:

The use of the RN as an internal fiducial marker for targeting the optimal region of STN stimulation was reliable and closely approximates the position of the electrode contact that provides the optimal clinical results.
Anterior Ethmoidal Artery: Microsurgical Anatomy and Technical Considerations
Authors: White Daniel V. , Sincoff Eric H. , Abdulrauf Saleem I.
Published: April 2005

OBJECTIVE:

Vascular lesions of the anterior cranial fossa can receive significant blood supply from the anterior ethmoidal artery. Embolization of this blood supply exposes the parent vessel, the ophthalmic artery, to possible embolic complications, which can lead to loss of vision. A study of the microsurgical anatomy can help delineate the course of the anterior ethmoidal artery and find the best points for proximal control of the blood supply to these lesions. Clinical cases are presented to illustrate how lesions with prominent anterior ethmoidal artery feeders are best approached through fronto-orbital single-flap craniotomies.

METHODS:

Eight cadaveric dissections to demonstrate the microsurgical anatomy of the anterior ethmoidal artery were performed to study the relevant anatomy. Two clinical cases are presented that demonstrate clinical application of this anatomy through fronto-orbital single-flap craniotomies.

RESULTS:

Eight arteries were studied in four cadaveric heads. The dissections show the course of the anterior ethmoidal artery from the ophthalmic artery in the orbit, through the anterior ethmoidal foramen into the ethmoid air cells, to the cribriform plate, where it turns superiorly to become the anterior falx artery. The first surgical case is of a giant tuberculum sellae meningioma that was resected with coagulation and division of the anterior ethmoidal arteries at the anterior ethmoidal foramina at the laminae papyraceae of both medial orbital walls. The second surgical case is of a large deep right frontal arteriovenous malformation that was resected with coagulation and division of the anterior ethmoidal artery at the anterior ethmoidal foramen of the lamina papyracea of the right medial orbital wall.

CONCLUSION:

The cadaveric dissections and our surgical experience show that the anterior ethmoidal artery has three important sites for surgical access: 1) the anterior ethmoidal foramen at the lamina papyracea of the medial orbital wall; 2) the anterior ethmoid canal at the lateral ethmoid wall; and 3) extradurally, at the cribriform plate. These three sites are best accessed through a fronto-orbital single-flap craniotomy, which can be unilateral or bilateral, depending on the pathological findings. The described orbital-cranial approach in this article is not being advocated to replace the standard pterional and frontal approaches; rather, we suggest it as an option in these complex cases that require early proximal control of the anterior ethmoidal artery feeders.
Intraoperative Awakening for Vision Examination during Ophthalmic Artery Aneurysm Clipping: Technical Case Report
Authors: Chen Peng , Dunn Ian F. , Aglio Linda S. , Day Arthur L. , Frerichs Kai U. , Friedlander Robert M.
Published: April 2005

OBJECTIVE AND IMPORTANCE:

We present a case of a patient with an ophthalmic artery aneurysm in which the ophthalmic artery originated from the body of the aneurysm, requiring sacrifice of the ophthalmic artery to achieve complete aneurysm obliteration. We awakened the patient intraoperatively to assess optic nerve function after clipping and were able to confirm optic nerve function. Controlled intraoperative awakening proved a valuable adjunct to intraoperative angiography in determining the immediate consequences of sacrifice of the ophthalmic artery.

CLINICAL PRESENTATION:

The patient was a 55-year-old right-handed woman with a 3-month history of episodic blurriness in her left eye; imaging demonstrated an unruptured 5-mm left ophthalmic artery aneurysm in which the ophthalmic artery originated from the body of the aneurysm.

INTERVENTION:

Complete obliteration of the aneurysm required clip placement across the neck of the aneurysm, incorporating not only the aneurysm but also the ophthalmic artery. Aware that sacrifice of the ophthalmic artery was likely, we awakened the patient after clipping and before dural closure to evaluate her optic nerve function. Once fully awake, the patient was able to execute simple commands and conclusively confirm light perception in both of her eyes. She was then reanesthetized, and intraoperative angiography showed successful aneurysm obliteration and parent artery patency.

CONCLUSION:

The ophthalmic artery can be sacrificed during aneurysm clipping without loss of vision in many cases, most likely because of adequate collateral filling from the external carotid artery. Certainty about the visual consequences of sacrifice of the ophthalmic artery, however, is difficult to obtain preoperatively or intraoperatively. Intraoperative awakening for evaluation of optic nerve function served as a useful technique to assess the acute results of interruption of ophthalmic artery flow in this case.
Coverage of Painful Peripheral Nerve Neuromas with Vascularized Soft Tissue: Method and Results
Authors: Krishnan Kartik G. , Pinzer Thomas , Schackert Gabriele
Published: April 2005

OBJECTIVE:

Our goals are to describe a method of treating painful peripheral nerve neuromas by means of vascularized tissue coverage, report the results in seven patients, and discuss the indications for this treatment modality. An analysis of pain, functionality of the affected body part, professional activities of the patients, and medications before and after surgery is presented.

METHODS:

Seven male patients (mean age, 45.1 yr) with posttraumatic nerve injuries, who had developed painful stump neuromas or neuromas-in-continuity, and who had unsuccessfully undergone several treatment procedures, were selected for the surgery described here. The operation included resection of the stump neuroma (four patients) or neurolysis of the neuroma-in-continuity (three patients) and coverage of the nerve with a vascularized fascial, fasciocutaneous, or perforator flap (three pedicled regional flaps and four free flaps). A modified quadruple visual analog scale was used to quantify pain before and after surgical treatment. The mean follow-up was 16.6 months.

RESULTS:

The mean values of the quadruple visual analog scale (pain now/typically/at its best/at its worst) before surgery were 6.5/6.5/4.7/7.9. These values changed to 0.3/0.4/0/0.9 at a mean follow-up of 16.6 months after surgery. Five patients returned to their original profession, one receives a pension, and one began a less demanding job after undergoing surgery. Six of the seven patients received opioids before surgery (one had a spinal cord stimulator). After surgery, all patients stopped taking regular pain killers and the spinal cord stimulator was deactivated in one; two patients still take nonsteroidal anti-inflammatory drugs occasionally, but not on a regular basis.

CONCLUSION:

Vascularized soft tissue coverage of painful peripheral nerve neuromas seems to be an effective and attractive, but also complex, method of treatment. This option may be considered and reserved for patients who have already undergone several pain treatment modalities without success.
Temporary Aneurysm Orifice Balloon Occlusion as an Alternative to Retrograde Suction Decompression for Giant Paraclinoid Internal Carotid Artery Aneurysms: Technical Note
Authors: Steiger Hans-Jakob , Lins Farias , Mayer Thomas , Schmid-Elsaesser Robert , Stummer Walter , Turowski Bernd
Published: April 2005

OBJECTIVE:

Giant paraclinoid carotid artery aneurysms frequently require the temporary interruption of local circulation to facilitate safe clip occlusion. Owing to the brisk retrograde blood flow through the ophthalmic artery and cavernous branches, the simple trapping of the aneurysm by cervical internal carotid artery clamping and intracranial distal clipping may not adequately soften the lesion. Retrograde suction decompression aspiration of this collateral supply by a catheter introduced into the cervical internal carotid artery is a popular method to achieve aneurysm deflation. With a large collateral supply, the method is not effective enough. The advent of relatively long and maneuverable soft balloons allows temporary occlusion of the aneurysm orifice.

METHODS:

We applied this method in two instances of giant carotid ophthalmic aneurysms. In both instances, a 15- to 20-mm-long and 4-mm-wide occlusion balloon was inserted in the internal carotid artery at the level of the aneurysm before craniotomy. After craniotomy and dissection of the aneurysm neck, the balloon was inflated under intraoperative angiographic control.

RESULTS:

The aneurysm became soft enough in both cases without tapping and aspiration to allow safe clip occlusion. In the first case, the postoperative course was uneventful and visual acuity improved. A known additional infraclinoid part of the aneurysm was eliminated endovascularly 5 months later using balloon-protected injection of vinyl alcohol copolymer (Onyx; Micro Therapeutics, Inc., Irvine, CA). In the second case, a postoperative symptomatic vasospasm developed 15 hours after surgery. Hypertensive therapy resulted in the disappearance of symptoms and an otherwise uneventful course with improvement of vision.

CONCLUSION:

This preliminary experience suggests that this new method is a feasible alternative to retrograde suction decompression.
Membranes and the setting of energy demand
Authors: Hulbert A. J. , Else P. L.
Published: April 2005

In his classic 1961 book, The Fire of Life, Max Kleiber presented a critique of the theories advanced to explain the BMR-body size relationship. One of the theories he dismissed was that the chemical composition of animals varies with body size. Since this time, however, much has been learned about the make-up of BMR in different animals as well as the chemical composition of different-sized animals. Specifically, in recent years it has become obvious that mammal species and bird species do vary in chemical composition in a systematic manner associated with the body size of the species. Small mammal and bird species have cellular membranes that are predominantly polyunsaturated, and as mammal and bird species increase in size, their cellular membranes become progressively less polyunsaturated. Since Kleiber's time, it has also become obvious that a substantial amount of the energy turnover of BMR is associated with the activity of membrane processes,specifically the maintenance of trans-membrane gradients, such as the Na+ gradient across the plasmalemmal membrane and the H+gradient across the mitochondrial inner membrane. The variation in both membrane composition and membrane processes associated with body size variation in metabolic rate has been combined in the `membrane pacemaker'theory of metabolism. This theory proposes that: (1) membrane-associated activities are significant and dominant components of BMR; (2) when BMR varies among species, all the activities that constitute BMR vary in unison; (3)species with high mass-specific BMR have highly polyunsaturated membranes while those with low BMR have less polyunsaturation of their membranes; (4)highly polyunsaturated membranes have distinctive physical properties that cause the proteins in the membranes to have a high molecular activity, and this results in higher rates of metabolism of cells, tissues and,consequently, the whole animal. Evidence supporting this theory is both correlative and experimental. Manipulation of membrane composition changes the molecular activity of membrane proteins. These differences in membrane composition may also represent a link between metabolism and aging. They probably explain the lifespan-body size relationship in mammals and birds and also the mammal-bird difference in lifespan.