bluuebunny/crossref_metadata_2025 huggingface dataset:
Fluid-sediment dynamics around a barb: an experimental case study of a hydraulic structure for the Pacific Northwest
Authors: Fox James F , Papanicolaou Athanasios N , Hobbs Brandon , Kramer Casey , Kjos Lisa
Published: December 2005

Three sets of experimental tests are administered in the vicinity of a model barb — a unique hydraulic structure used to provide bank protection for mild-sloped, gravel-bed streams in the Pacific Northwest — under modeled, bankfull conditions. First, experiments are performed using acoustic Doppler velocimetry to provide a description of the flow characteristics around the model barb, as this is the first time that this type of structure has been considered. These initial experiments provide quantitative flow regimes as a guide for scour and spacing tests. Second, scour around the structure is described because existing knowledge in the literature is limited to scour in sand bed streams. Lastly, the performance of the barbs as it relates to bank protection is evaluated using the large-scale particle-image velocimeter for the first time to the authors' knowledge. The results provide quantification of three distinct flow regimes around a barb, scour geometry, and dimensionless ratios for scour depth and spacing for the barbs when designed for bankfull discharge in the Pacific Northwest.Key words: streambank erosion, bank stabilization, barb, flow diversion, hydraulic structure, turbulent eddies.
A new concept of isolation bearings for highway steel bridges using shape memory alloys
Authors: Choi Eunsoo , Nam Tae-hyun , Cho Baik-Soon
Published: December 2005

Conventional lead–rubber bearings (LRB) may have a problem of instability and unrecovered deformation with a strong ground motion. To improve the problems, this study proposed a new concept of an isolation device in which shape memory alloy wires were incorporated in an elastomeric bearing. This study illustrated the behavior of shape memory alloy in tension and discussed the variation of stiffness and stress on the hyteresis curves. A three-span continuous steel bridge was used for seismic analyses to compare the performance of lead–rubber bearings with the proposed bearings. This study showed that large residual deformation of LRB occurred even with a weak ground motion of peak ground acceleration (PGA) of 0.2g. The proposed bearings effectively limited the relative displacement of the deck when tested for the strong ground motions and almost recovered the original undeformed shape. However, the proposed bearing increases the demand on bridge columns compared with the LRB.Key words: shape memory alloy, lead–rubber bearings, seismic bridge analysis, isolation device, residual deformation.
The organization, structure, and inheritance of the ER in higher and lower eukaryotes
Authors: de Martin Paula Estrada , Novick Peter , Ferro-Novick Susan
Published: December 2005

The endoplasmic reticulum (ER) is a fundamental organelle required for protein assembly, lipid biosynthesis, and vesicular traffic (McMaster 2001; Staehelin 1997; Voeltz et al. 2002), as well as calcium storage and the controlled release of calcium from the ER lumen into the cytosol (Johnson and van Waes 1999; Ma and Hendershot 2002; Matlack et al. 1998; Meldolesi and Pozzan 1998). Membranes functionally linked to the ER by vesicle-mediated transport, such as the Golgi complex, endosomes, vacuoles–lysosomes, secretory vesicles, and the plasma membrane, originate largely from proteins and lipids synthesized in the ER (Voeltz et al. 2002). In this review we will discuss the structural organization of the ER and its inheritance.Key words: ER structure, organelle inheritance.
Modified expressions for substrate flux into biofilm
Authors: Fouad Moharram , Bhargava Renu
Published: December 2005

The present study was carried out to simplify existing biofilm one-dimensional models, which consider a single substrate as the limiting factor. Models of Suidan and Wang (1985) and Sáez and Rittmann (1988, 1992) were selected for the present study. Thus, modified expressions were developed for the first one, while the exact solution of the second one could be obtained. The modified expressions and the exact solution are short, simple, easy to use, and give reliable results in comparison to the original models. In addition, the proposed expressions and solution can be used instead of the graphical solutions, which are commonly used to solve the original models. Applicability of the developed expressions has been demonstrated through an illustrative example. The proposed expressions and the present study may be useful to simplify the description of biofilm in many systems such as completely mixed or fluidized-bed reactor for treatment of water or wastewater as well as the biofilm-activated sludge reactors. Moreover, the exact solution from this study can be used to establish the biofilm kinetics instead of using the curve-matching technique. Key words: biofilm, model, modified expressions, steady state, substrate flux.
Succession of microfungal communities on decaying leaves ofCastanopsis fissa
Authors: Tang Alvin M.C , Jeewon Rajesh , Hyde Kevin D
Published: December 2005

A total of 38 fungal taxa were identified on senescent untreated and autoclaved Castanopsis fissa leaves during a 4-month study period. Seventy-six percent of the fungal genera found in this survey have not previously been recorded from Castanopsis. Frequency and time of occurrence of fungal taxa occurring on untreated senescent leaves were clustered into four groups when analyzed by cluster analysis, suggesting the replacement of microfungi in stages of succession on naturally senescent leaves. Autoclaved leaves revealed significantly different fungal communities, with only 26% of overlap with the natural ones and no clear patterns of replacement of fungal communities. Factors regulating the rates of decomposition are also discussed.Key words: Castanopsis, decomposition fungal ecology, fungal succession, microfungi.
Culture-dependent and -independent approaches establish the complexity of a PAH-degrading microbial consortium
Authors: Viñas Marc , Sabaté Jordi , Guasp Caterina , Lalucat Jorge , Solanas Anna M
Published: December 2005

A microbial consortium (AM) obtained by sequential enrichment in liquid culture with a polycyclic aromatic hydrocarbon (PAH) mixture of three- and four-ringed PAHs as a sole source of carbon and energy was examined using a triple-approach method based on various cultivation strategies, denaturing gradient gel electrophoresis (DGGE), and the screening of 16S and 18S rRNA gene clone libraries. Eleven different sequences by culture-dependent techniques and seven by both DGGE and clone libraries were obtained. The comparison of three variable regions (V3–V5) of the 16S rRNA gene between the sequences obtained yielded 19 different microbial components. Proteobacteria were the dominant group, representing 83% of the total, while the Cytophaga–Flexibacter–Bacteroides group (CFB) was 11% and the Ascomycota fungi 6%. β-Proteobacteria were predominant in the DGGE and clone library methods, whereas they were a minority in culturable strains. The highest diversity and number of noncoincident sequences were achieved by the cultivation method that showed members of the α-, β-, and γ-Proteobacteria; CFB bacterial group; and Asco mycota fungi. Only six of the 11 strains isolated showed PAH-degrading capability. The bacterial strain (AMS7) and the fungal strain (AMF1), which were similar to Sphingomonas sp. and Fusarium sp., respectively, achieved the greatest PAH depletion. The results indicate that polyphasic assessment is necessary for a proper understanding of the composition of a microbial consortium.Key words: microbial consortium, microbial diversity, PAHs, DGGE, 16S rRNA gene.
Twenty-five years since the discovery of endothelium-derived relaxing factor (EDRF): does a dysfunctional endothelium contribute to the development of type 2 diabetes?
Authors: Triggle Chris R , Howarth Andrew , Cheng Zhong Jian , Ding Hong
Published: December 2005

Twenty-five years ago, the discovery of endothelium-derived relaxing factor opened a door that revealed a new and exciting role for the endothelium in the regulation of blood flow and led to the discovery that nitric oxide (NO) multi-tasked as a novel cell-signalling molecule. During the next 25 years, our understanding of both the importance of the endothelium as well as NO has greatly expanded. No longer simply a barrier between the blood and vascular smooth muscle, the endothelium is now recognized as a complex tissue with heterogeneous properties. The endothelium is the source of not only NO but also numerous vasoactive molecules and signalling pathways, some of which are still not fully characterized such as the putative endothelium-derived relaxing factor. Dysfunction of the endothelium is a key risk factor for the development of macro- and microvascular disease and, by coincidence, the discovery that NO was generated in the endothelium corresponds approximately in time with the increased incidence of type 2 diabetes. Primarily linked to dietary and lifestyle changes, we are now facing a global pandemic of type 2 diabetes. Characterized by insulin resistance and hyperglycaemia, type 2 diabetes is increasingly being diagnosed in adolescents as well as children. Is there a link between dietary-related hyperglycaemic insults to the endothelium, blood flow changes, and the development of insulin resistance? This review explores the evidence for and against this hypothesis.Key words: diabetes, endothelium, hyperglycaemia, insulin, nitric oxide, oxidative stress.
CONFLICT RESOLUTION IN INSECT SOCIETIES
Authors: Ratnieks Francis L.W. , Foster Kevin R. , Wenseleers Tom
Published: December 2005

▪ Abstract  Although best known for cooperation, insect societies also manifest many potential conflicts among individuals. These conflicts involve both direct reproduction by individuals and manipulation of the reproduction of colony members. Here we review five major areas of reproductive conflict in insect societies: (a) sex allocation, (b) queen rearing, (c) male rearing, (d) queen-worker caste fate, and (e) breeding conflicts among totipotent adults. For each area we discuss the basis for conflict (potential conflict), whether conflict is expressed (actual conflict), whose interests prevail (conflict outcome), and the factors that reduce colony-level costs of conflict (conflict resolution), such as factors that cause workers to work rather than to lay eggs. Reproductive conflicts are widespread, sometimes having dramatic effects on the colony. However, three key factors (kinship, coercion, and constraint) typically combine to limit the effects of reproductive conflict and often lead to complete resolution.
SIGNALING AND FUNCTION OF INSULIN-LIKE PEPTIDES IN INSECTS
Authors: Wu Qi , Brown Mark R.
Published: December 2005

▪ Abstract  Insulin-like peptides (ILPs) exist in insects and are encoded by multigene families that are expressed in the brain and other tissues. Upon secretion, these peptides likely serve as hormones, neurotransmitters, and growth factors, but to date, few direct functions have been demonstrated. In Drosophila melanogaster, molecular genetic studies have revealed elements of a conserved insulin signaling pathway, and as in other animal models, it appears to play a key role in metabolism, growth, reproduction, and aging. This review offers (a) an integrated summary of the efforts to characterize the distribution of ILPs in insects and to define this pathway and its functions in Drosophila and (b) a few considerations for future studies of ILP endocrinology in insects.
HIV VACCINES
Authors: McMichael Andrew J.
Published: December 2005

A prophylactic vaccine for HIV-1 is badly needed. Despite 20 years of effort, it is still a long way off. However, considerable progress has been made in understanding the problem. The virus envelope has evolved to evade neutralizing antibodies in an extraordinary way, yet a vaccine that can stimulate such antibodies remains the best hope. Anti-HIV-1 T cell responses are evaded by continuous mutation of the virus. Vaccine strategies that concentrate on stimulating T cell immunity will at best generate broadly reactive and persisting T cell responses that can suppress virus without preventing infection, limiting or preventing the damage the virus causes. The SIV macaque models give encouragement that this is possible, but they need further understanding. Therapeutic vaccination should also be considered.
The minimum tree for a given zero‐entropy period
Authors: Barrabés Esther , Juher David
Published: December 2005

We answer the following question: given any n ∈ ℕ, which is the minimum number of endpoints en of a tree admitting a zero‐entropy map f with a periodic orbit of period n?
We prove that , where n = s1s2 … sk is the decomposition of n into a product of primes such that si ≤ si+1 for 1 ≤ i < k. As a corollary, we get a criterion to decide whether a map f defined on a tree with e endpoints has positive entropy: if f has a periodic orbit of period m with em > e, then the topological entropy of f is positive.
Stoneley waves in a non‐homogeneous orthotropic granular medium under the influence of gravity
Authors: Ahmed S. M.
Published: December 2005

The aim of this paper is to investigate the Stoneley waves in a non‐homogeneous orthotropic granular medium under the influence of a gravity field. The frequency equation obtained, in the form of a sixth‐order determinantal expression, is in agreement with the corresponding result when both media are elastic. The frequency equation when the gravity field is neglected has been deduced as a particular case.
Moving Griffith crack in an orthotropic strip with punches at boundary faces
Authors: Mukherjee S. , Das S.
Published: December 2005

Integral transform technique is employed to solve the elastodynamic problem of steady‐state propagation of a Griffith crack centrally situated along the midplane of orthotropic strip of finite thickness 2h and subjected to point loading with centrally situated moving punches under constant pressure along the boundaries of the layer. The problem is reduced to the solution of a pair of simultaneous singular integral equations with Cauchy‐type singularities which have finally been solved through the finite Hilbert transform technique. For large h, analytical expression for the stress intensity factor at the crack tip is obtained. Graphical plots of the numerical results are also presented.
A note on the strong law of large numbers for associated sequences
Authors: Nezakati A.
Published: December 2005

We prove that the sequence converges a.e. to zero if {Xn, n ≥ 1} is anassociated sequence of random variables with where {bn, n ≥ 1} is a positive nondecreasing sequence and {kn, n ≥ 1} is a strictly increasing sequence, both tending to infinity as n tends to infinity and .
One Cycle of Bleomycin, Etoposide and Cisplatin plus Two Cycles of Etopeside and Cisplatin Chemotherapy in Selected Patients with Low-Volume Stage II Nonseminomatous Germ Cell Tumor of the Testis
Authors: Mezvrishvili Zaza , Managadze Laurent
Published: December 2005

Objective: To assess the feasibility of bleomycin omission from second and third cycles of bleomycin, etoposide and cisplatin (BEP) chemotherapy in low-volume stage II nonseminomatous germ cell tumor patients who achieve a normal tumor marker level after the first cycle of treatment. Materials and Methods: Out of 59 nonseminomatous testicular cancer patients with low-volume retroperitoneal disease, serum markers normalized after the first cycle of treatment in 30 cases. 12 patients completed 3BEP (group 1; years 1994–1998) and other 18 patients received etoposide and cisplatin (EP) as second and third cycles of chemotherapy (group 2; years 1998–2004). Results: All patients from each group achieved complete response with chemotherapy alone or by subsequent resection of teratoma or necrosis. There was no relapse with active cancer after the treatment. All patients remained disease-free during the median follow-up period of 97 and 48 months for groups 1 and 2 respectively. Conclusions: One cycle of BEP plus two cycles of EP chemotherapy was as effective as three standard cycles of BEP. The regimen can be suggested as a less toxic therapeutic alternative in these selected patients. More cases, however, in a prospective randomized setting are required to further verify these data.
Multi-Tract Percutaneous Nephrolithotomy for Large Complete Staghorn Calculi
Authors: Aron Monish , Yadav Rajiv , Goel Rajiv , Kolla Surendra B. , Gautam Gagan , Hemal Ashok K. , Gupta Narmada P.
Published: December 2005

Introduction: The treatment of large complete staghorn calculi requires a sandwich combination of percutaneous nephrolithotomy (PCNL) and shockwave lithotripsy (SWL) or sometimes open surgery. Many urologists hesitate to place more than 2–3 tracts during PCNL because of the belief that this may increase complications. We present data to support multi-tract PCNL for large (surface area >3,000 mm2) complete staghorn calculi. Patients and Methods: From July 1998 to October 2003, 121 renal units (103 patients) with large complete staghorn renal calculi were treated with PCNL. All procedures were performed in the prone position after retrograde ureteral catheterization. Fluoroscopy-guided punctures were made by the urologist followed by track dilation to 34 french. When multiple tracts were anticipated all punctures were usually made at the outset and preplaced wires were put into the collecting system or down the ureter. Stones were fragmented and removed using a combination of pneumatic lithotripsy and suction. Postoperative stone clearance was documented on X-ray KUB. Results: 121 renal units of 103 patients (15 women and 88 men, mean age 43 years) were treated. Six patients had associated bladder calculi that were treated simultaneously. The stone surface area was 3,089–6,012 (mean 4,800) mm2. 10 patients (9.7%) had renal insufficiency with a mean (range) serum creatinine of 3.0 (1.5–5.5) mg/dl. The number of tracts required per patient were 2 tracts in 11, 3 tracts in 68, 4 tracts in 39, and 5 tracts in 3, giving a total of 397 tracts in 121 renal units, over a total of 140 procedures (including second-look procedures in 19 renal units). The points of entry of these tracts were 121 upper calyx (30.4%), 178 middle calyx (44.8%), and 98 lower calyx (24.6%). All 121 units had one upper polar access tract of which 92 (76%) were supracostal. Complications were blood transfusion (n = 18), pseudoaneurysm (n = 2), fever (n = 22), septic shock (n = 1) and hydrothorax (n = 3). PCNL monotherapy achieved an 84% complete clearance rate that improved to 94% with SWL in 8 renal units with small residual fragments. Stone compositions were calcium oxalate (91%), uric acid (2%) and mixed (7%). Conclusion: Aggressive PCNL monotherapy using multiple tracts is safe and effective, and should be the first option for massive renal staghorn calculi.
E-Cadherin Gene 3′-UTR C/T Polymorphism Is Associated with Prostate Cancer
Authors: Wu Hsi-Chin , Lai Ming-Tsung , Wu Chao-I , Chen Huey-Yi , Wan Lei , Tsai Fuu-Jen , Chen Wen-Chi
Published: December 2005

Introduction: E-cadherin (CDH-1) is a cell-cell adhesive molecule which maintains cell integrity and communication between the intracellular and extracellular world. CDH-1 may therefore be related to carcinogenesis. A polymorphism located at the 3′-UTR of the CDH-1 gene is associated with stone disease; however, its relationship to prostate cancer has not been reported. We aimed to study whether there is an association between the 3′-UTR polymorphism and prostate cancer. Materials and Methods: We collected 96 patients with prostate cancer and 114 normal controls for this study. The polymorphism of the CDH-1 gene was studied by polymerase chain reaction-based restriction analysis. Results:There was a significant difference in genotype distribution of the CDH-1 gene polymorphism between cancer patients and normal controls (p < 0.001). The distribution of the CDH-1 gene CC genotype in prostate cancer patients (51.0%) was higher than in the controls (10.5%). The odds ratio for the CDH-1 ‘C’ allele was 2.896 (95% CI = 1.908–4.396). There was no significant difference according to age, pathological grading, clinical staging, and responsiveness to hormonal therapy among patients. Only 3 patients (3.1%) had a history of urolithiasis. Conclusions:The CDH-1 gene 3′-UTR C/T polymorphism is associated with prostate cancer. The ‘CC’ homozygote indicates a relatively higher risk for developing prostate cancer than other genotypes.
Large-Cell Calcifying Sertoli Cell Tumour of the Testis Detected at Screening of a Family with Carney Syndrome
Authors: Jayasena S.N. , Ariyasinghe J.T.N. , Gunawardena D.M.R. , Gunawardena S.A.S. , de Silva M.V.C.
Published: December 2005

We report the detection of a large-cell calcifying Sertoli cell tumour (LCCSCT) in a 34-year-old male during screening of a family with Carney syndrome. The patient had ignored the testicular swelling for 7 years. He also had a cardiac myxoma. The LCCSCT in this patient had prognostically unfavourable features such as large size (>6 cm) and a high mitotic rate. There is only one previous report of a malignant LCCSCT in a patient with Carney syndrome.
Asymptomatic Cerebrovascular Disease and Systemic Diagnosis in Stroke, Atherothrombosis as a Disease of the Vascular Tree
Authors: Gállego Jaime , Martínez-Vila Eduardo
Published: December 2005

Atherosclerosis is a chronic vascular disease of true epidemic proportions. It is the first cause of death in developed countries and responsible for one quarter of documented deaths worldwide. Arteriosclerotic vascular disease is a systemic process which affects different organs; principally the heart, brain, and peripheral artery system. Despite well-documented differences, all manifestations of the disease share the same risk factors; albeit with varying degrees of impact. The concept of asymptomatic cerebrovascular disease is an important one for clinicians who treat stroke patients. The development of new neuroimaging and vascular evaluation techniques has enabled the presence of apparently silent lesions to be detected and their progress monitored in follow-up. Ultrasonography techniques enable the identification of atheromatous disease. Asymptomatic involvement of the cerebral parenchyma consists of ischemia, leukoaraiosis, and silent hemorrhage and can be detected using the available radiological techniques such as cranial CT, magnetic resonance, or gradient echo magnetic resonance imaging. From the point of view of prevention, it is of considerable importance to identify diagnostic markers for arteriosclerosis in asymptomatic patients in some, if not all, vascular territories. In view of the natural history of this disease and the impact it has on society, there is an increasing need to identify and understand the risk factors or vascular disease risk markers, so that the stratification of risk of an individual patient or in a specific population can be established, appropriate cerebrovascular assessments conducted, and appropriate therapeutic intervention initiated.
How Healthy Is the Acutely Reperfused Ischemic Penumbra?
Authors: Baron J.-C.
Published: December 2005

Because it is the main determinant of clinical recovery, early reperfusion of the ischemic penumbra has become the mainstay of acute stroke therapy. Although early permanent recanalization can be associated with spectacular and complete recovery, some patients in fact exhibit delayed or incomplete recovery, even despite small infarcts on late structural imaging. This might result from tissue inflammation and selective neuronal death/damage, two probably inter-related cellular events well described in the animal literature, precluding full functional restoration in the salvaged penumbra. However, impact of these processes on recovery may be complex because of the interplay with ongoing plasticity and the possible promoting effect of inflammation on the latter. Preliminary results from imaging studies of inflammation and selective neuronal loss after middle cerebral artery territory stroke, using radioligands of the central benzodiazepine receptor and the activated microglia, respectively, reviewed here, suggest these phenomena also exist in man, although their relationship with acute-stage hypoperfusion and their impact on clinical recovery, if any, remain poorly understood. Furthermore, their inter-relationships in the salvaged penumbra have not been addressed. Better understanding of these potentially harmful processes might help to maximize benefits from thrombolysis, and could also have implications for patients who enjoy spontaneous recanalization.
Homeostasis as Basis of Acute Stroke Treatment: Stroke Units Are the Key
Authors: Díez-Tejedor E. , Fuentes B.
Published: December 2005

Introduction:Several studies suggest that the control of blood pressure (BP), blood glucose level, body temperature, and oxygen saturation, when analyzed separately, is related with successful acute stroke outcome. However, in a biological system these parameters are interrelated and could influence the process. Recent studies highlight the importance of the appropriate maintenance of these variables that are involved in homeostasis in patients with stroke and the influence they have on outcome. Methods: A review was conducted of published studies which analyzed the influence of control of these physiological variables in acute stroke, whether in isolation or combinations, and we have contributed our own data derived from observational studies. Results: The maintenance of homeostasis forms the basis of acute stroke treatment, in what is termed nonpharmacological neuroprotection. Stroke units (SU) are the ideal environment for this therapeutic approach since their favorable influence on the correct management of BP, body temperature, oxygen saturation, and blood glucose in the progress of stroke patients have been proved. Conclusions: The proper management of physiological variables (homeostasis) such as BP, body temperature, blood glucose, and oxygen saturation is the basis of acute stroke treatment, and SU are the key to this approach.
Thrombolysis in Acute Ischemic Stroke: Successes, Failures, and New Hopes
Authors: Dávalos Antoni
Published: December 2005

Evidence from randomized clinical trials indicates that systemic administration of recombinant tissue plasminogen activator (rtPA) is a highly effective treatment for acute ischemic stroke, provided that treatment is administered within the first 3 h after stroke onset. An absolute increase in favorable outcome of up to 13% has been reported, and a pooled analysis of six randomized trials has shown that, although the sooner rtPA is given the greater the benefit, efficacy is present up to 4.5 h after stroke onset. Despite of the spreading use of tPA in different countries and continents, there are still a number of burdens and failures in the optimal accomplishment of thrombolytic treatment. rtPA is used in less than 4% of patients, reperfusion and complete recovery is achieved in less than 50% of patients, and treatment is denied to many patients. However, important advances in clinical investigation suggest that new aims and hopes will be achieved in the near future. Ultrasound-enhanced systemic thrombolysis, the use of MRI for selecting acute stroke patients for IV or IA thrombolysis after 3 h, mechanical embolus disruption or removal in proximal artery occlusions, and the potential usefulness of new biomarkers of blood brain barrier disruption and hemorrhagic risk are promising strategies that may improve the risk/benefit ratio and increase the number of patients who will benefit from thrombolytic therapy.
Recent Advances in the Interventional Treatment of Acute Ischemic Stroke
Authors: Higashida Randall T.
Published: December 2005

Background: Acute ischemic stroke is a major cause of morbidity and mortality in Europe, North America, and Asia. Recent advances over the past decade have been made in the interventional approach to patients with a stroke. These include intravenous (IV) trials, intra-arterial (IA) trials, combined IV/IA trials, and newer devices undergoing current clinical evaluation to mechanically remove clot within the cerebral circulation. Methods: A summary of the latest interventional approaches to stroke, from the interventional neuroradiology perspective, is presented. Results of the major thrombolytic trials over the past decade are summarized. Newer devices and approaches for ischemic stroke patients, including the recently completed Phase 1/2 MERCI (Mechanical Embolus Removal in Cerebral Ischemia) Trial are presented. Results: The Proact 1 and 2 trials involving IA thrombolytic therapy in patients who present with an acute middle cerebral artery stroke within 6 h from symptom onset have demonstrated significant benefit over the control group, for improved outcomes at 90 days. The MERCI trial has demonstrated, in 114 patients with moderate to severe strokes, that patients who are able to be recanalized have significant neurological improvement versus those who were not able to be recanalized. Conclusions: Continued advances in the interventional approach to acute stroke treatment, with further clinical trials, are warranted. Early reports are encouraging regarding both combination thrombolytic drug trials and mechanical device trials for these patients.
New Goals in Ischemic Stroke Therapy: The Experimental Approach – Harmonizing Science with Practice
Authors: Alonso de Leciñana María , Díez-Tejedor Exuperio , Gutierrez María , Guerrero Sandra , Carceller Fernando , Roda Jose María
Published: December 2005

Undeniable advances have been made in clinical and experimental investigation into the pathophysiology, diagnosis, and treatment of cerebral ischemia. However, with the exception of intravenous thrombolysis and some neuroprotectors, such as citicoline, the majority of the drugs successfully tested in experimental studies have failed in clinical trials. Valuable lessons for the improvement of research methodology and appropriate coordination of experimental and clinical research can be learnt from the analysis of discrepancies between the laboratory and clinic, which will allow us to increase the power and cost-effectiveness of the studies. In addition, this progress has opened the way for the investigation of very promising new therapeutic strategies, such as combined pharmacological and mechanical thrombolysis, thrombolysis and neuroprotection, or the combination of various neuroprotectors, antiapoptotic therapies, and neurorestoration therapies, such as stem cell transplants.
Surgical Treatment of Cervicofacial Cystic Hygromas in Children
Authors: Ozen I. Onur , Moralioglu Serdar , Karabulut Ramazan , Demirogullari Billur , Sonmez Kaan , Turkyilmaz Zafer , Basaklar A. Can , Kale Nuri
Published: December 2005

Aim: The aim of this study was to evaluate the results of surgical treatment of cervicofacial cystic hygromas in children. Patients and Methods: Medical records of 17 patients who were operated for cervicofacial cystic hygroma between 1985 and 2004 were evaluated in terms of age, gender, symptoms, diagnostic workups, outcomes and complications. Results: There was a slight male predominance – 10 (59%) boys and 7 (41%) girls. Nine (53%) out of 17 lesions were located on the left side of the neck, 7 (41%) lesions were located on the right side of the neck and 1 lesion (6%) was located in the middle of the neck. Eleven (65%) lesions were located in the infrahyoid region, 6 (35%) lesions in the suprahyoid region. Following surgical excision of the lesion, we encountered 4 postoperative complications: 1 recurrence (6%), 2 facial paralyses (12%) and 1 collection of fluid (6%) at the resection site. The patient who had a recurring lesion needed to be reoperated, other complications were treated conservatively. Conclusions: Cervicofacial cystic hygromas are easy to diagnose. There is no need for expensive and time-consuming imaging studies. Surgery seems the treatment of choice. However, nonsurgical treatment options may be considered for the lesions located over the parotid region in order to avoid complications of surgery.
Postural Control after Vestibular Schwannoma Resection Measured with Visual Feedback Posturography
Authors: Hirvonen Meeli , Aalto Heikki , Hirvonen Timo P.
Published: December 2005

Background: Vestibular symptoms after surgery diminish rapidly, but the simultaneous progress in active postural control has not been fully addressed. Objectives: The aim was to evaluate the progress in postural control in operated vestibular schwannoma (VS) patients with visual feedback posturography (VFP). Methods: 36 consecutive patients with unilateral VS were studied with the VFP pre-operatively, 1 month and 3 months after the surgery. The accuracy and velocity of active postural control movements to distant targets in VFP was measured and compared to that of healthy controls. Results: The hold percentage within the targets was significantly reduced in the VS patients compared to the controls (pre-operatively p = 0.005; postoperatively at 1 month p = 0.002 and at 3 months p = 0.017). The sway velocity (SV) within the targets among patients with VS was significantly increased pre-operatively (p = 0.009), at the 1-month (p = 0.004) and at the 3-month follow-up visits (p = 0.016). All the postural control parameters except SV tended to improve slightly postoperatively. The consecutive VFP measurements in individual VS patients correlated statistically significantly (p < 0.001 for all parameters). The abnormality in the pre-operative VFP results correlated statistically significantly with that of postoperative VFP (p = 0.001). Conclusions: The VFP is an objective and repeatable method, which can be used to assess and follow up the active postural control in individual patients with VS. Persisting abnormality in the VFP seems to be an indication for more aggressive vestibular rehabilitation to normalize the disturbed postural control.
Subjective Visual Horizontal and Stabilometer Findings in Patients with Unilateral Severe Vestibular Dysfunction
Authors: Takai Yoshinari , Iwasaki Shinichi , Murofushi Toshihisa
Published: December 2005

The records of both stabilometer and subjective visual horizontal (SVH) testing can be used to evaluate vestibular compensation. When results of SVH testing have a strong significant correlation to those of stabilometer testing, clinicians can omit one of two tests from the test battery. To investigate the correlation, results of these two tests of patients with unilateral severe vestibular dysfunction were studied. Twenty-eight patients, 20 men and 8 women, with unilateral severe vestibular dysfunction were enrolled in this study. The correlation between these two tests was considered not significant according to the results. In conclusion, we cannot omit either stabilometer testing or SVH testing for the evaluation of patients with vestibular dysfunction.
Congenital Muscular Torticollis in Children
Authors: Sönmez Kaan , Türkyilmaz Zafer , Demiroğulları Billur , Özen I. Onur , Karabulut Ramazan , Bağbancı Barış , Başaklar A. Can , Kale Nuri
Published: December 2005

Aim: The aim of this study was to evaluate the data of our patients treated for congenital muscular torticollis (CMT) in the period between 1990 and 2004. Here we report our clinical experience with CMT and review the literature. Patients and Methods: We retrospectively evaluated the data of our patients in terms of age, sex, clinical presentation, additional deformities, localization of the lesion, history of previous treatment attempts, diagnostic tests, additional abnormalities, findings at operation and surgical procedures. Results: The mean age of the patients who were operated for CMT (25 females, 27 males) was 4.3 years (range: 5 months to 16 years). Most of the lesions were seen on the left aspect of the neck. There was only one case with bilateral CMT. Seventeen out of 52 patients with CMT (32%) were diagnosed in the newborn period. The most encountered complaint at application was restriction of neck motion (57%). Associated complaints such as head tilt (53%), fascial asymmetry (34%), deformity of the skull (9.6%) were seen. Sternocleidomastoid tumor accounted for only 11% of the patients’ complaints. All patients in this series were treated by surgical intervention. Apart from one recurrence no other postoperative complication was observed during the follow-up period. Conclusions: Patients whose pathology does not resolve after 12 months of physical therapy or who develop facial asymmetry or plagiocephaly during the follow-up period should be operated on in order to achieve the best cosmetic result. In delayed cases additional surgery may be needed for the best cosmetic and functional result.
Losartan Attenuates Bleomycin-Induced Pulmonary Fibrosis in Rats
Authors: Yao Hong Wei , Zhu Jian Ping , Zhao Meng Hui , Lu Yuan
Published: December 2005

Background: In addition to regulating blood pressure and body fluid homeostasis, the renin-angiotensin system is also involved in lung fibrogenesis. Objective: To study the effect of losartan, an angiotensin II antagonist, on bleomycin-induced pulmonary fibrosis in rats and its possible mechanism. Methods: Pulmonary fibrosis was induced in SD rats by intratracheal instillation of bleomycin (5 mg·kg–1). Subsequently, the rats received daily losartan (3, 9 and 27 mg·kg–1) or prednisone (20 mg·kg–1) orally. Six rats in each group were sacrificed 14 and 21 days after intratracheal instillation. Hydroxyproline, superoxide dismutase (SOD), and malondialdehyde (MDA) levels in lung tissues were determined by spectroscopy. The levels of TGF-β1 in serum were measured by ELISA. Histological changes in the lungs were evaluated by hematoxylin-eosin stain, and scored. Results: Rat body weight evidently decreased while the indices of lung and hydroxyproline contents in lung tissue were significantly increased 14 and 21 days after intratracheal bleomycin instillation. Inflammatory cell infiltration and fibrotic scores were more prominent in the model group compared to the sham group. Losartan (3, 9 and 27 mg·kg–1, i.g.) apparently attenuated the degree of pulmonary fibrosis. Further study showed that losartan significantly increased SOD levels while it decreased MDA contents in lung homogenates. Serum TGF-β1 levels of pulmonary fibrosis rats were also decreased by losartan. Conclusions: Losartan had an inhibitory effect on bleomycin-induced pulmonary fibrosis, and its effect may be associated with its anti-free radicals and the reduction in TGF-β1.
Early Socioeconomic Position and Blood Pressure in Childhood and Adulthood
Authors: Kivimäki Mika , Lawlor Debbie A. , Smith George Davey , Keltikangas-Järvinen Liisa , Elovainio Marko , Vahtera Jussi , Pulkki-Råback Laura , Taittonen Leena , Viikari Jorma S.A. , Raitakari Olli T.
Published: December 2005

Studies have found an association between low socioeconomic position in childhood and high adult blood pressure. It is unclear whether this association is explained by a pathway directly linking disadvantage to elevated blood pressure in childhood and adolescence, which then tracks into adulthood. We assessed parental socioeconomic position and systolic blood pressure in 1807 children and adolescents ages 3 to 18 years at baseline. Adult systolic blood pressure was measured 21 years later at ages 24 to 39 years. There was strong tracking of blood pressure from childhood to adulthood. Lower parental socioeconomic position was associated with higher blood pressure in childhood, adolescence (
P
<0.01), and adulthood (
P
<0.0001), with the mean age- and sex-adjusted systolic pressure differences between the highest and lowest socioeconomic groups varying between 2.9 and 4.3 mm Hg. With adjustment for blood pressure in childhood and adolescence, the regression coefficient between parental socioeconomic position and adult blood pressure attenuated by 32%. A similar level of attenuation (28%) occurred with adjustment for adult body mass index (BMI). With adjustment for both preadult blood pressure and adult BMI, the association between parental socioeconomic position and adult blood pressure was attenuated by 45%. Other factors, including birth weight and BMI in childhood and adolescence, had little impact on the association between parental socioeconomic position and adult blood pressure. These data suggest that early socioeconomic disadvantage influences later blood pressure in part through an effect on blood pressure in early life, which tracks into adulthood, and in part through an effect on BMI.
Cost-Effectiveness Analysis of Hypertension Guidelines in South Africa
Authors: Gaziano Thomas A. , Steyn Krisela , Cohen David J. , Weinstein Milton C. , Opie Lionel H.
Published: December 2005

Background—

Hypertension is responsible for more deaths worldwide than any other cardiovascular risk factor. Guidelines based on blood pressure level for initiation of treatment of hypertension may be too costly compared with an approach based on absolute cardiovascular disease (CVD) risk, especially in developing countries.

Methods and Results—

Using a Markov CVD model, we compared 6 strategies for initiation of drug treatment—2 different blood pressure levels (160/95 and 140/90 mm Hg) and 4 different levels of absolute CVD risk over 10 years (40%, 30%, 20%, and 15%)—with one of no treatment. We modeled a hypothetical cohort of all adults without CVD in South Africa, a multiethnic developing country, over 10 years. The incremental cost-effectiveness ratios for treating those with 10-year absolute risk for CVD >40%, 30%, 20%, and 15% were $700, $1600, $4900, and $11 000 per quality-adjusted life-year gained, respectively. Strategies based on a target blood pressure level were both more expensive and less effective than treatment decisions based on the strategy that used absolute CVD risk of >15%. Sensitivity analysis of cost of treatments, prevalence estimates of risk factors, and benefits expected from treatment did not change the ranking of the strategies.

Conclusions—

In South Africa, current guidelines based on blood pressure levels are both more expensive and less effective than guidelines based on absolute risk of cardiovascular disease. The use of quantitative risk-based guidelines for treatment of hypertension could free up major resources for other pressing needs, especially in developing countries. (Circulation. 2005;112:3569-3576.)
Tuberculous Pericarditis
Authors: Mayosi Bongani M. , Burgess Lesley J. , Doubell Anton F.
Published: December 2005

Background—

The incidence of tuberculous pericarditis is increasing in Africa as a result of the human immunodeficiency virus (HIV) epidemic. The primary objective of this article was to review and summarize the literature on the pathogenesis, diagnosis, and management of tuberculous pericarditis.

Methods and Results—

We searched MEDLINE (January 1966 to May 2005) and the Cochrane Library (Issue 1, 2005) for information on relevant references. A “definite” diagnosis of tuberculous pericarditis is based on the demonstration of tubercle bacilli in pericardial fluid or on a histological section of the pericardium; “probable” tuberculous pericarditis is based on the proof of tuberculosis elsewhere in a patient with otherwise unexplained pericarditis, a lymphocytic pericardial exudate with elevated adenosine deaminase levels, and/or appropriate response to a trial of antituberculosis chemotherapy. Treatment consists of the standard 4-drug antituberculosis regimen for 6 months. It is uncertain whether adjunctive corticosteroids are effective in reducing mortality or progression to constriction. Surgical resection of the pericardium remains the appropriate treatment for constrictive pericarditis. The timing of surgical intervention is controversial, but many experts recommend a trial of medical therapy for noncalcific pericardial constriction, and pericardiectomy in nonresponders after 4 to 8 weeks of antituberculosis chemotherapy.

Conclusions—

Research is needed to improve the diagnosis, assess the effectiveness of adjunctive steroids, and determine the impact of HIV infection on the outcome of tuberculous pericarditis.
Cardiovascular Complications of Diabetes Mellitus in Sub-Saharan Africa
Authors: Kengne André Pascal , Amoah Albert G.B. , Mbanya Jean-Claude
Published: December 2005

Background—

Cardiovascular disease, the major cause of mortality and morbidity in modern societies, is set to overtake infectious diseases in the developing world as the most common cause of death. The increasing prevalence of major and emerging cardiovascular risk factors accounts for the growing burden of cardiovascular disease in the world. Diabetes in all its forms is one of the main cardiovascular risk factors. Two of 3 diabetic patients will die as a result of cardiovascular complications, and approximately 30% of patients treated in cardiovascular intensive care units have diabetes.

Methods and Results—

This review on the cardiovascular complications of diabetes in sub-Saharan Africa is a bibliographical MEDLINE search of published data over the past 2 decades. Diabetes-related cardiovascular disease complications are considered to be rare in Africa but are on the rise and are regularly associated with classic cardiovascular risk factors. Coronary heart disease may affect 5% to 8% of type 2 diabetic patients and cardiomyopathy, up to 50% of all patients. Close to 15% of patients with stroke have diabetes, and up to 5% of diabetic patients present with cerebrovascular accidents at diagnosis. Peripheral vascular disease prevalence varies across sites from 4% to 28%.

Conclusions—

It is obvious that diabetes mellitus and related cardiovascular complications are gaining more importance in sub-Saharan Africa. The relative contribution of putative risk factors is not well defined, and further research is therefore needed. (Circulation. 2005;112:3592-3601.)
Impact of Human Immunodeficiency Virus Infection on Cardiovascular Disease in Africa
Authors: Ntsekhe Mpiko , Hakim James
Published: December 2005

Background—

Human immunodeficiency virus (HIV) infection is the single greatest health challenge facing Africa today. However, the impact of the HIV epidemic on the cardiovascular system in Africans has received scant attention in the world literature.

Methods and Results—

We searched MEDLINE (January 1, 1980, to December 31, 2004) and reference lists of literature on HIV and the heart in Africa and contacted experts in the field. The search for this review yielded 22 articles involving HIV and the cardiovascular system from 8 countries in Africa.

Conclusions—

The available information suggests that there are unique features in the etiology, presentation, and spectrum of HIV-associated cardiovascular disorders in people living in Africa. First, pericardial disease may be the initial manifestation of HIV infection in the early stages of the illness. Second, the etiology of cardiac disease tends to reflect the prevalent infectious diseases, such as tuberculosis. Third, unique cardiovascular disorders such as aneurysm of large vessels have been reported in association with HIV infection in several parts of Africa. Finally, the HIV/AIDS pandemic has put pressure on the meager healthcare resources and fragile infrastructure in many African countries, making the diagnosis and treatment of heart disease unrelated to HIV even more difficult.