bluuebunny/crossref_metadata_2025 huggingface dataset:
Role of Pressure in Angiotensin II-Induced Renal Injury
Authors: Mori Takefumi , Cowley Allen W.
Published: February 2004

Renal perfusion pressure was servo-controlled chronically in rats to quantify the relative contribution of elevated arterial pressure versus angiotensin II (Ang II) on the induction of renal injury in Ang II-induced hypertension. Sprague-Dawley rats fed a 4% salt diet were administered Ang II for 14 days (25 ng/kg per minute IV; saline only for sham rats), and the renal perfusion pressure to the left kidney was continuously servo-controlled to maintain a normal pressure in that kidney throughout the period of hypertension. An aortic occluder was implanted around the aorta between the two renal arteries and carotid and femoral arterial pressure were measured continuously throughout the experiment to determine uncontrolled and controlled renal perfusion pressure, respectively. Renal perfusion pressure of uncontrolled, controlled, and sham kidneys over the period of Ang II or saline infusion averaged 152.6±7.0, 117.4±3.5, and 110.7±2.2 mm Hg, respectively. The high-pressure uncontrolled kidneys exhibited tubular necrosis and interstitial fibrosis, especially prominent in the outer medullary region. Regional glomerular sclerosis and interlobular artery injury were also pronounced. Controlled kidneys were significantly protected from interlobular artery injury, juxtamedullary glomeruli injury, tubular necrosis, and interstitial fibrosis as determined by comparing the level of injury. Glomerular injury was not prevented in the outer cortex. Transforming growth factor (TGF)-β and active NF-κB proteins determined by immunohistochemistry were colocalized in the uncontrolled kidney in regions of interstitial fibrosis. We conclude that the preferential juxtamedullary injury found in Ang II hypertension is largely induced by pressure and is probably mediated through the TGF-β and NF-κB pathway.
Impaired 11-β Hydroxysteroid Dehydrogenase Type 2 Activity in Sweat Gland Ducts in Human Essential Hypertension
Authors: Bocchi Brigitte , Kenouch Sabine , Lamarre-Cliche Maxime , Muffat-Joly Martine , Capron Michel Hubert , Fiet Jean , Morineau Gilles , Azizi Michel , Bonvalet Jean Pierre , Farman Nicolette
Published: February 2004

The enzyme 11-β hydroxysteroid dehydrogenase type 2 plays a major role in blood pressure regulation. It metabolizes glucocorticoid hormones into derivatives with low affinity for the mineralocorticoid receptor, preventing its permanent occupancy by circulating cortisol, which is 100- to 1000-fold more abundant than aldosterone in the plasma. Inactivating mutations of the enzyme result in severe hypertension, as seen in children with apparent mineralocorticoid excess syndrome. In patients with essential hypertension, however, attempts to evidence enzyme deficiency have been inconclusive. In this pilot study, its catalytic activity was measured directly in aldosterone-sensitive sweat gland ducts collected from skin biopsy samples of 10 male normotensive subjects and 10 subjects with essential hypertension (more than 140 to 90 mm Hg) with no sign of hypermineralocorticism. Isolated ducts were assayed for nicotinamide-dinucleotide-dependent dehydrogenase activity (transformation of tritiated corticosterone into tritiated-11 dehydrocorticosterone, as measured by high-pressure liquid chromatography). Hypertensive patients exhibited significantly lower 11-β hydroxysteroid dehydrogenase type 2 activity (9.7±4.7 femtomoles per 3 mm length of duct and per 10 minutes incubation, median±SD) than did normotensive subjects (15.9±2.6). Such defect was undetectable using the classical urinary corticosteroid metabolism indexes, probably because of compensatory mechanisms. Relations between these findings and blood pressure levels should benefit from direct enzyme measurements in the vasculature. In conclusion, this cross-sectional study points to partial 11-β hydroxysteroid dehydrogenase type 2 deficiency as a novel feature of essential hypertension, which should stimulate search for new signaling pathways and therapeutical targets.
Baroreflex Buffering of Sympathetic Activation During Sleep
Authors: Iellamo Ferdinando , Placidi Fabio , Marciani Maria Grazia , Romigi Andrea , Tombini Mario , Aquilani Stefano , Massaro Michele , Galante Alberto , Legramante Jacopo M.
Published: February 2004

We examined the effects of sleep microstructure, ie, the cyclic alternating pattern (CAP), on heart rate (HR)- and blood pressure (BP)-regulating mechanisms and on baroreflex control of HR in healthy humans and tested the hypothesis that sympathetic activation occurring in CAP epochs during non-rapid eye movement (non-REM) sleep periods is buffered by the arterial baroreflex. Ten healthy males underwent polysomnography and simultaneous recording of BP, ECG, and respiration. Baroreflex sensitivity (BRS) was calculated by the sequences method. Autoregressive power spectral analysis was used to investigate R-R interval (RRI) and BP variabilities. During overall non-REM sleep, BP decreased and RRI increased in comparison to wakefulness, with concomitant decreases in low-frequency RRI and BP oscillations and increases in high-frequency RRI oscillations. These changes were reversed during REM to wakefulness levels, with the exception of RRI. During CAP, BP increased significantly in comparison to non-CAP and did not differ from REM and wakefulness. The low-frequency component of BP variability was significantly higher during CAP than non-CAP. RRI and its low-frequency spectral component did not differ between CAP and non-CAP. BRS significantly increased during CAP in comparison to non-CAP. BRS was not different during CAP and REM and was greater during both in comparison with the awake state. Even during sleep stages, like non-REM sleep, characterized by an overall vagal predominance, phases of sustained sympathetic activation do occur that resemble that occurring during REM. Throughout the overnight sleep period, the arterial baroreflex acts to buffer surges of sympathetic activation by means of rapid changes in cardiac vagal circuits.
Fibroblast Network in Rabbit Sinoatrial Node
Authors: Camelliti Patrizia , Green Colin R. , LeGrice Ian , Kohl Peter
Published: February 2004

Cardiomyocytes form a conducting network that is assumed to be electrically isolated from nonmyocytes in vivo. In cell culture, however, cardiac fibroblasts can contribute to the spread of excitation via functional gap junctions with cardiomyocytes. To assess the ability of fibroblasts to form gap junctions in vivo, we combine in situ detection of connexins in rabbit sinoatrial node (a tissue that is particularly rich in fibroblasts) with identification of myocytes and fibroblasts using immunohistochemical labeling and confocal microscopy. We distinguish two spatially distinct fibroblast populations expressing different connexins: fibroblasts surrounded by other fibroblasts preferentially express connexin40, whereas fibroblasts that are intermingled with myocytes largely express connexin45. Functionality of homogeneous and heterogeneous cell coupling was investigated by dye transfer in sinoatrial node tissue explants. These studies reveal spread of Lucifer yellow, predominantly along extended threads of interconnected fibroblasts (probably via connexin40), and occasionally between neighboring fibroblasts and myocytes (probably via connexin45). Our findings show that cardiac fibroblasts form a coupled network of cells, which may be functionally linked to myocytes in rabbit SAN.
Opioid-Induced Cardioprotection Occurs via Glycogen Synthase Kinase β Inhibition During Reperfusion in Intact Rat Hearts
Authors: Gross Eric R. , Hsu Anna K. , Gross Garrett J.
Published: February 2004

Glycogen synthase kinase (GSK) inhibition produced by ischemic preconditioning has been previously shown to be regulated through phosphatidylinositol-3 kinase (PI3K). Therefore, we determined whether opioid-induced cardioprotection (OIC) occurs during reperfusion by altering GSK phosphorylation through PI3K and target of rapamycin (TOR). Furthermore, we determined if selective GSK inhibitors, SB216763(SB21) or SB415286(SB41), emulate OIC. Rats were treated with the nonselective opioid agonist, morphine (MOR, 0.3 mg/kg), the δ-selective opioid agonist BW373U86 (BW, 1 mg/kg), or the GSK inhibitors, SB21 (0.6 mg/kg) or SB41(1.0 mg/kg), either 10 minutes before ischemia or 5 minutes before reperfusion. Five minutes before opioid or SB21 treatment, some rats received either the PI3K inhibitor wortmannin (15 μg/kg) or LY294002 (0.3 mg/kg) or the TOR inhibitor rapamycin (3 μg/kg). After 30 minutes of ischemia followed by 2 hours of reperfusion, infarct size was assessed. MOR, BW, SB41, and SB21 reduced infarct size compared with vehicle when administered before ischemia (42.9±2.6, 40.3±2.3, 46.6±1.6, 42.2±1.8 versus 60.0±1.1%, respectively;
P
<0.001) and showed similar protection when administered 5 minutes before reperfusion (43.6±2.3, 40.2±2.6, 44.8±2.8, 39.4±0.8%, respectively;
P
<0.001). Wortmannin, LY294002, and rapamycin were found to inhibit OIC; however, they did not abrogate SB21-induced infarct size reduction. At 5 minutes of reperfusion, both MOR and BW increased P-GSKβ at Ser
9
in the ischemic zone compared with vehicle (181±20, 178±15 versus 75±17 DU, respectively;
P
<0.05), and this effect was abrogated by prior administration of wortmannin or rapamycin in MOR-treated rats. Furthermore, no differences were seen in phosphorylation of GSKα (Ser
21
or Tyr
279
) or phosphorylation of GSKβ (Tyr
216
). These data indicate that OIC occurs via the phosphorylation of GSKβ at Ser
9
during reperfusion.
Blood Pressure and Stroke
Authors: Lawes Carlene M.M. , Bennett Derrick A. , Feigin Valery L. , Rodgers Anthony
Published: February 2004

Background—

The last few years have seen a considerable increase in the amount of information available concerning blood pressure (BP) and stroke associations. This article provides an overview of published reviews of the effects on stroke seen in trials of BP-lowering drugs and compares these with the results available from cohort studies.

Summary of Review—

We present a review of major overviews of prospective cohort studies and an updated meta-analysis of >40 randomized controlled trials of BP lowering, which included >188 000 participants and approximately 6800 stroke events. Cohort studies now indicate that in the Asia Pacific region as well as in North America and Western Europe, each 10 mm Hg lower systolic BP is associated with a decrease in risk of approximately one third in subjects aged 60 to 79 years. The association is continuous down to levels of at least 115/75 mm Hg and is consistent across sexes, regions, and stroke subtypes and for fatal and nonfatal events. The proportional association is age dependent but is still a strong and positive association in those aged 80 years. Data from randomized controlled trials, in which mean age at event was approximately 70 years, indicate that a 10 mm Hg reduction in systolic BP is associated with a reduction in risk of stroke of approximately one third. Per mm Hg systolic BP reduction, the benefits for stroke appear similar between agents, by baseline BP levels, and whether or not individuals have a past history of cardiovascular disease. There is, however, evidence of greater benefit with a larger BP reduction.

Conclusions—

The epidemiologically expected benefits of BP lowering for stroke risk reduction are broadly consistent across a range of different population subgroups. There are greater benefits from larger BP reductions, and initiating and maintaining BP reduction for stroke prevention is a more important issue than choice of initial agent.
Estimating the Cost-Effectiveness of Stroke Units in France Compared With Conventional Care
Authors: Launois R. , Giroud M. , Mégnigbêto A.C. , Le Lay K. , Présenté G. , Mahagne M.H. , Durand I. , Gaudin A.F.
Published: February 2004

Background and Purpose—

The incidence of stroke in France is estimated at between 120 000 and 150 000 cases per year. This modeling study assessed the clinical and economic benefits of establishing specialized stroke units compared with conventional care.

Methods—

Data from the Dijon stroke registry were used to determine healthcare trajectories according to the degree of autonomy and organization of patient care. The relative risks of death or institutionalization or death or dependence after passage through a stroke unit were compared with conventional care. These risks were then inserted with the costing data into a Markov model to estimate the cost-effectiveness of stroke units.

Results—

Patients cared for in a stroke unit survive more trimesters without sequelae in the 5 years after hospitalization than those cared for conventionally (11.6 versus 8.28 trimesters). The mean cost per patient at 5 years was estimated at 30 983

for conventional care and 34 638

in a stroke unit. An incremental cost-effectiveness ratio for stroke units of 1359

per year of life gained without disability was estimated.

Conclusions—

The cost-effectiveness ratio for stroke units is much lower than the threshold (53 400

) of acceptability recognized by the international scientific community. This finding justifies organizational changes in the management of stroke patients and the establishment of stroke units in France.
Appearance of Early Venous Filling During Intra-Arterial Reperfusion Therapy for Acute Middle Cerebral Artery Occlusion
Authors: Ohta Hajime , Nakano Shinichi , Yokogami Kiyotaka , Iseda Tsutomu , Yoneyama Takumi , Wakisaka Shinichiro
Published: February 2004

Background and Purpose—

The purpose of this study was to evaluate the correlation between appearance of angiographic early venous filling during intra-arterial reperfusion therapy and posttherapeutic hemorrhagic complications.

Methods—

For the past 7 years, 104 patients prospectively underwent superselective local angiography via a microcatheter before and during intra-arterial reperfusion therapy for acute middle cerebral artery occlusion to evaluate the presence or absence of early venous filling. In principle, reperfusion therapy was discontinued just after appearance of early venous filling for fear of hemorrhage. There were 2 types of early venous filling: early filling of the thalamostriate vein from the lenticulostriate arteries and that of the cortical vein from the cortical arteries.

Results—

Among these 104 patients, 31 (29.8%) had early venous filling: 19 had early filling of the thalamostriate vein, and the other 12 had early filling of the cortical vein. Eight of the 19 patients (42.1%) and 2 of the 12 patients (16.7%) had massive hematoma with neurological worsening, whereas only 1 of the 73 patients (1.4%) without early venous filling had massive hematoma. There was a significant correlation between early venous filling and massive hematoma in both the deep (
P
<0.0001) and superficial (
P
=0.0019) middle cerebral artery territories. The sensitivity and specificity of the presence of early venous filling as an indicator of parenchymal hematoma were 71% and 83%, respectively. None of the 31 ischemic areas with early venous filling could escape cerebral infarction.

Conclusions—

Appearance of early venous filling may indicate irreversible brain damage and may be a predictive sign for parenchymal hematoma.
Frequency and Determinants of Poststroke Dementia in Chinese
Authors: Tang Wai Kwong , Chan Sandra S.M. , Chiu Helen F.K. , Ungvari Gabor S. , Wong Ka Sing , Kwok Timothy C.Y. , Mok Vincent , Wong K.T. , Richards Polly S. , Ahuja A.T.
Published: February 2004

Background and Purpose—

Both dementia and stroke are major health problems in Chinese societies. Stroke is a frequent cause of dementia. Only a few studies have been published on poststroke dementia (PSDE), none of which has investigated a consecutive stroke cohort in Asian patient populations. The objective of this study was to examine the prevalence and clinical correlates of PSDE in Chinese stroke patients in Hong Kong.

Methods—

Two hundred eighty stroke patients consecutively admitted to the medical wards of a university-affiliated regional hospital were interviewed by a psychiatrist 3 months after stroke. The presence of dementia and vascular dementia was diagnosed according to the
Diagnostic and Statistical Manual
, 4th edition. In addition, a wide range of demographic and clinical variables were examined.

Results—

Fifty-five participants (20%) had PSDE. Univariate analysis found that PSDE was associated with age; level of education; prestroke Rankin Scale score; prestroke Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) score; National Institutes of Health Stroke Scale (NIHSS) best language score, dysarthria score, and total score; urinary incontinence; cortical infarct; leukoaraiosis; bilateral lesions; number of lesions; involvement of middle cerebral artery circulation; and cerebral atrophy index. Multivariate logistic regression suggested that prestroke IQCODE score, NIHSS total score, leukoaraiosis, involvement of middle cerebral artery territory, and cerebral atrophy index were independent risk factors of PSDE. After removal of 22 patients with prestroke dementia, which was defined as a prestroke IQCODE score ≥4.0, the frequency of PSDE dropped to 15.5%. Furthermore, involvement of the middle cerebral artery territory and cerebral atrophy index were replaced by level of education and bilateral lesions as independent predictors in the final logistic model.

Conclusions—

PSDE is common among Chinese stroke patients in Hong Kong. Its frequency is comparable to that in white populations. The clinical determinants of PSDE, after the exclusion of patients with prestroke dementia, include premorbid level of cognitive function, severity of stroke, leukoaraiosis, level of education, and bilateral lesions.
Hemangiopoietin, a novel human growth factor for the primitive cells of both hematopoietic and endothelial cell lineages
Authors: Liu Yong Jun , Lu Shi Hong , Xu Bin , Yang Ren Chi , Ren Qian , Liu Bin , Li Bin , Lu Min , Yan Feng Ying , Han Zhi Bo , Han Zhong Chao
Published: February 2004

The cells of hematopoietic and vascular endothelial cell lineages are believed to share a common precursor, termed hemangioblast. However, the existence of a growth factor acting relatively specifically on hemangioblasts remains unclear. Here we report the identification of hemangiopoietin (HAPO), a novel growth factor acting on both hematopoietic and endothelial cell lineages. In vitro in the human system, recombinant human HAPO (rhHAPO) significantly stimulated the proliferation and hematopoietic and/or endothelial differentiation of human bone marrow mononuclear cells and of purified CD34+, CD133+, kinase domain receptor-positive (KDR+), or CD34+/KDR+ cell populations. In the murine system, rhHAPO stimulated the proliferation of long-term culture-initiating cells (LTC-ICs) as well as CD34+ and stem cell antigen-1 (Sca-1+) cell subsets. In vivo, subcutaneous injection of rhHAPO into normal mice resulted in a significant increase in bone marrow hematopoietic cells. Furthermore, irradiated mice injected with rhHAPO had an enhanced survival rate and accelerated hematopoiesis. Our data suggest that HAPO is a novel growth factor acting on the primitive cells of both hematopoietic and endothelial cell lineages and that HAPO may have a clinical potential in the treatment of various cytopenias and radiation injury and in the expansion of hematopoietic and endothelial stem/progenitor cells. (Blood. 2004;103:4449-4456)
SOCS1 and SHP1 hypermethylation in multiple myeloma: implications for epigenetic activation of the Jak/STAT pathway
Authors: Chim Chor-Sang , Fung Tsz-Kin , Cheung Wai-Chung , Liang Raymond , Kwong Yok-Lam
Published: February 2004

SOCS1 and SHP1 negatively regulate the Janus kinase/signal transducer and activator of transcription (Jak/STAT) signaling pathway. The role of promoter hypermethylation leading to epigenetic inactivation of SOCS1 and SHP1 in myeloma was investigated. The methylation-specific polymerase chain reaction (MSP) was used to define SOCS1 and SHP1 methylation in 34 diagnostic myeloma samples. For SOCS1, MSP primers 3′ to the translation start site were unreliable and gave positive results in normal controls. However, primers in the 5′ promoter region were specific, although no myeloma samples showed methylation. For SHP1, 27 of 34 (79.4%) myeloma samples showed SHP1 hypermethylation. The biologic significance of SHP1 methylation was investigated in the U266 human myeloma line. U266 contained completely methylated SHP1. Furthermore, there was constitutive STAT3 phosphorylation. Treatment with 5-azacytidine led to progressive demethylation of SHP1 on days 2 to 5, with consequent increasing reexpression of SHP1 as shown by reverse transcription-polymerase chain reaction (RT-PCR). Concomitant with increasing SHP1, a parallel down-regulation of phosphorylated STAT3 occurred, so that by day 5 phosphorylated STAT3 was barely detectable. The overall survivals of patients with and without SHP1 methylation were similar. SHP1 methylation leading to epigenetic activation of the Jak/STAT pathway might have a tentative role in the pathogenesis of myeloma, which should be further confirmed by functional studies in primary myeloma samples. (Blood. 2004;103:4630-4635)
Modification of hematopoietic stem cell fate by 5aza 2′deoxycytidine and trichostatin A
Authors: Milhem Mohammed , Mahmud Nadim , Lavelle Donald , Araki Hiroto , DeSimone Joseph , Saunthararajah Yogen , Hoffman Ronald
Published: February 2004

Efforts to change the fate of human hematopoietic stem cells (HSCs) and progenitor cells (HPCs) in vitro have met with limited success. We hypothesized that previously utilized in vitro conditions might result in silencing of genes required for the maintenance of primitive HSCs/HPCs. DNA methylation and histone deacetylation are components of an epigenetic program that regulates gene expression. Using pharmacologic agents in vitro that might possibly interfere with DNA methylation and histone deacetylation, we attempted to maintain and expand cells with phenotypic and functional characteristics of primitive HSCs/HPCs. Human marrow CD34+ cells were exposed to a cytokine cocktail favoring differentiation in combination with 5aza 2′deoxycytidine (5azaD) and trichostatin A (TSA), resulting in a significant expansion of a subset of CD34+ cells that possessed phenotypic properties as well as the proliferative potential characteristic of primitive HSCs/HPCs. In addition, 5azaD- and TSA-pretreated cells but not the CD34+ cells exposed to cytokines alone retained the ability to repopulate immunodeficient mice. Our findings demonstrate that 5azaD and TSA can be used to alter the fate of primitive HSCs/HPCs during in vitro culture.
Induction of antigen-specific tolerance to bone marrow allografts with CD4+CD25+ T lymphocytes
Authors: Joffre Olivier , Gorsse Nathalie , Romagnoli Paola , Hudrisier Denis , van Meerwijk Joost P. M.
Published: February 2004

Thymus-derived regulatory T lymphocytes of CD4+CD25+ phenotype regulate a large variety of beneficial and deleterious immune responses and can inhibit lethal graft-versus-host disease in rodents. In vitro, CD4+CD25+ T cells require specific major histocompatibility complex (MHC)/peptide ligands for their activation, but once activated they act in an antigen-nonspecific manner. In vivo, regulatory T cells are also activated in an antigen-specific fashion, but nothing is known about antigen specificity of their suppressor-effector function. Here we show that CD4+CD25+ regulatory T lymphocytes isolated from naive mice and activated in vitro with allogeneic antigen-presenting cells (APCs) induced specific long-term tolerance to bone marrow grafts disparate for major and minor histocompatibility antigens; whereas “target” bone marrow was protected, third-party bone marrow was rejected. Importantly, in mice injected with a mix of target and third-party bone marrows, protection and rejection processes took place simultaneously. These results indicate that CD4+CD25+ regulatory T cells can act in an antigen-specific manner in vivo. Our results suggest that CD4+CD25+ regulatory T cells could in the future be used in clinical settings to induce specific immunosuppression. (Blood. 2004;103:4216-4221)
Predicting safety and quality of thermally processed canned foods using a neural network
Authors: Kseibat D. S. , Mittal G. S. , Basir O. A.
Published: February 2004

An artificial neural network (ANN) for reliably predicting the process temperature (Te) and process time (t) for minimum quality degradation (Foq) during thermal processing of canned foods was developed. Five inputs (can size, initial temperature, thermal diffusivity, sensitivity indicator of micro-organism and sensitivity indicator of quality) were used to predict the process variables Te, t, and Foq. A measure of dependency and statistical tests were used to reduce the number of inputs with little degradation of ANN performance. The feedforward ANN showed satisfactory prediction error. The mean relative error (MRE) was 0.2% in predicting Te, 3.9% in predicting t, and 1.5% in predicting Foq. The ANN showed high MRE in predicting the outputs when tested with the radial basis function (RBF) network.
Wrapping strategies for temperature control of chilled foodstuffs during transport
Authors: Stubbs D. M. , Pulko S. H. , Wilkinson A. J.
Published: February 2004

There is a growing market for food producers to supply their goods direct to customers, which has largely been brought about by the growing popularity of web-based ordering. However, the geographical distance between supplier and consumer can be large and this presents problems if temperature-sensitive foods are to be transported. Here we describe a numerical model for the thermal experience of foodstuff packaged in expanded polystyrene boxes in the presence of a gel refrigerant. The model is validated by comparing predicted temperatures with those measured in the laboratory, and the model is then used to investigate the effect that the quantity and placement of gel refrigerant and the ambient temperature have on the period for which maximum food temperature can be maintained below 5°C and 8°C. Results indicate that it is possible to maintain chilled food below these temperatures for up to 24 h, though this period is dependent upon ambient temperature, the manner in which the refrigerant is wrapped around the food and the position of a food item inside the box.
Conceptual design and evaluation of an ultrasonic system for bottled beverages’ quality measurement and control
Authors: Zhao B. , Basir O. A. , Mittal G. S.
Published: February 2004

A conceptual design of an online ultrasonic system for bottled beverages’ quality control and monitoring is presented. The design consists of being able to measure ultrasound propagation velocities of beverages in each glass bottle without needing to know its diameter and wall thickness. This was achieved using simultaneously both ultrasound pulse/echo and thru-transmission signals. The ultrasound velocity is then correlated with the beverage’s, viscosity, which is an index of quality. The design also includes: (1) an online transducer alignment technique using a mechanism of frequency shift in spectrum of an ultrasonic pulse signal according to incident angle, and (2) a signal processing method using a slide window technique suitable for automatic separation and recognition of narrowly spaced pulse signals. Experiments were conducted to evaluate the design. Results of beverage viscosity/velocity correlation, frequency shift due to transducer alignment, and ultrasound velocity measurement in real bottles are reported.
Combining Gene Expression Profiles and Clinical Parameters for Risk Stratification in Medulloblastomas
Authors: Fernandez-Teijeiro Ana , Betensky Rebecca A. , Sturla Lisa M. , Kim John Y.H. , Tamayo Pablo , Pomeroy Scott L.
Published: February 2004

Purpose

Stratification of risk in patients with medulloblastoma remains a challenge. As clinical parameters have been proven insufficient for accurately defining disease risk, molecular markers have become the focus of interest. Outcome predictions on the basis of microarray gene expression profiles have been the most accurate to date. We ask in a multivariate model whether clinical parameters enhance survival predictions of gene expression profiles.

Patients and Methods

In a cohort of 55 young patients (whose medulloblastoma samples have been analyzed previously for gene expression profile), associations between clinical and gene expression variables and survival were assessed using Cox proportional hazards models. Available clinical variables included age, stage (ie, the presence of disseminated disease at diagnosis), sex, histologic subtype, treatment, and status.

Results

Univariate analysis demonstrated expression profiles to be the only significant clinical prognostic factor (P = .03). In multivariate analysis, gene expression profiles predicted outcome independent of other criteria. Clinical criteria did not significantly contribute additional information for outcome predictions, although an exploratory analysis noted a trend for decreased survival of patients with metastases at diagnosis but favorable gene expression profile.

Conclusion

Gene expression profiling predicts medulloblastoma outcome independent of clinical variables. These results need to be validated in a larger prospective study.
Trastuzumab in the Treatment of Advanced Non-Small-Cell Lung Cancer: Is There a Role? Focus on Eastern Cooperative Oncology Group Study 2598
Authors: Langer Corey J. , Stephenson Patricia , Thor Ann , Vangel Mark , Johnson David H.
Published: February 2004

Purpose

Multiple non–small-cell lung cancer (NSCLC) cell lines and 20% to 50% of pathologic specimens express HER-2/neu, the target of trastuzumab, and HER-2/neu expression has proven to be an independent, unfavorable prognostic factor in resected patients with NSCLC. Trastuzumab, in vitro, has demonstrated growth-inhibiting synergy with platinating agents, and additivity with paclitaxel. The Eastern Cooperative Oncology Group therefore launched a phase II study evaluating combination carboplatin, paclitaxel, and trastuzumab in patients with advanced NSCLC.

Materials and Methods

Eligibility stipulated the following: measurable tumor, HER-2/neu positivity (1+ to 3+ by Herceptest [Dako Corp, Carpinteria, CA], confirmed by central review), Eastern Cooperative Oncology Group PS 0 to 1, adequate marrow, hepatic and renal function, and left ventricular ejection fraction ≥ 45%. Patients received paclitaxel 225 mg/m2/3 hours, and carboplatin (area under the curve, 6) every 3 weeks, and trastuzumab 4 mg/kg intravenously on day 1, then 2 mg/kg weekly for ≤ 1 year.

Results

Between August 1999 and May 2000, 139 patients were screened; seven specimens (5%) were indeterminate. Fifty patients (36%) were HER-2/neu negative, 38 (27%) were HER-2/neu 1+, 31 (22%) were 2+, and 13 (9%) were 3+. Fifty-six patients were enrolled; 53 were eligible (22 [42%] were 1+, 23 (43%) were 2+, and eight (15%) were 3+). Thirteen (24.5%) of 52 assessable patients (95% CI, 13.8 to 38.3) responded. The incidence of grade ≥ 3 neutropenia and thrombocytopenia was 57% (34%) and 16% (2%), respectively. Asymptomatic grade ≤ 2 reduction in left ventricular ejection fraction occurred in 7%. Other nonhematologic toxicities, including nausea, fatigue, arthralgias, and peripheral sensory neuropathy, were mild to moderate and matched those expected with carboplatin and paclitaxel alone. Eighteen patients (35%) received maintenance trastuzumab. Median progression-free survival was 3.3 months; median survival was 10.1 months, and 1-year survival rate was 42%.

Conclusion

Combination paclitaxel, carboplatin, and trastuzumab is feasible. Toxicity appears no worse than cytotoxic therapy alone. Overall survival is similar to historical data using carboplatin and paclitaxel alone. However, patients with 3+ HER-2/neu expression did well in contrast to historical data suggesting potential benefit for trastuzumab in this rare subset of NSCLC. Critical assessment of trastuzumab's role in advanced NSCLC will require phase III trials.
Bilateral Prophylactic Mastectomy Reduces Breast Cancer Risk in BRCA1 and BRCA2 Mutation Carriers: The PROSE Study Group
Authors: Rebbeck Timothy R. , Friebel Tara , Lynch Henry T. , Neuhausen Susan L. , van ’t Veer Laura , Garber Judy E. , Evans Gareth R. , Narod Steven A. , Isaacs Claudine , Matloff Ellen , Daly Mary B. , Olopade Olufunmilayo I. , Weber Barbara L.
Published: February 2004

Purpose

Data on the efficacy of bilateral prophylactic mastectomy for breast cancer risk reduction in women with BRCA1 and BRCA2 (BRCA1/2) mutations are limited, despite the clinical use of this risk-management strategy. Thus, we estimated the degree of breast cancer risk reduction after surgery in women who carry these mutations.

Patients and Methods

Four hundred eighty-three women with disease-associated germline BRCA1/2 mutations were studied for the occurrence of breast cancer. Cases were mutation carriers who underwent bilateral prophylactic mastectomy and who were followed prospectively from the time of their center ascertainment and their surgery, with analyses performed for both follow-up periods. Controls were BRCA1/2 mutation carriers with no history of bilateral prophylactic mastectomy matched to cases on gene, center, and year of birth. Both cases and controls were excluded for previous or concurrent diagnosis of breast cancer. Analyses were adjusted for duration of endogenous ovarian hormone exposure, including age at bilateral prophylactic oophorectomy if applicable.

Results

Breast cancer was diagnosed in two (1.9%) of 105 women who had bilateral prophylactic mastectomy and in 184 (48.7%) of 378 matched controls who did not have the procedure, with a mean follow-up of 6.4 years. Bilateral prophylactic mastectomy reduced the risk of breast cancer by approximately 95% in women with prior or concurrent bilateral prophylactic oophorectomy and by approximately 90% in women with intact ovaries.

Conclusion

Bilateral prophylactic mastectomy reduces the risk of breast cancer in women with BRCA1/2 mutations by approximately 90%.
Clinical, Histopathologic, and Molecular Markers of Prognosis: Toward a New Disease Risk Stratification System for Medulloblastoma
Authors: Gajjar Amar , Hernan Roberto , Kocak Mehmet , Fuller Christine , Lee Youngsoo , McKinnon Peter J. , Wallace Dana , Lau Ching , Chintagumpala Murali , Ashley David M. , Kellie Stewart J. , Kun Larry , Gilbertson Richard J.
Published: February 2004

Purpose

To assess the feasibility of performing central molecular analyses of fresh medulloblastomas obtained from multiple institutions and using these data to identify prognostic markers for contemporaneously treated patients.

Materials and Methods

Ninety-seven samples of medulloblastoma were collected. Tumor content in samples was judged by frozen section review. Tumor ERBB2 protein and MYCC, MYCN, and TRKC mRNA levels were measured blind to clinical details using Western blotting and real-time polymerase chain reaction, respectively. Histopathologic and clinical review of each case was also performed. All data were subjected to independent statistical analysis.

Results

Sample acquisition and analysis times ranged from 3 to 6 days. Eighty-six samples contained sufficient tumor for analysis, including 38 classic, 30 nodular desmoplastic, and 18 large-cell anaplastic (LCA) medulloblastomas. Protein and mRNA were extracted from 81 and 49 tumors, respectively. ERBB2 was detected in 40% (n = 32 of 81) of tumors, most frequently in LCA disease (P = .005), and was independently associated with a poor prognosis (P = .031). A combination of clinical characteristics and ERBB2 expression provided a highly accurate means of discriminating disease risk. One hundred percent (n = 26) of children with clinical average-risk, ERBB2-negative disease were alive at 5 years, with a median follow-up of 5.6 years, compared with only 54% for children with average-risk, ERBB2-positive tumors (n = 13; P = .0001). TRKC, MYCC, and MYCN expression and histopathologic subtype were not associated with prognosis in this study.

Conclusion

Central and rapid molecular analysis of frozen medulloblastomas collected from multiple institutions is feasible. ERBB2 expression and clinical risk factors together constitute a highly accurate disease risk stratification tool.
Transactivation of the Insulin-Like Growth Factor-I Receptor by Angiotensin II Mediates Downstream Signaling from the Angiotensin II Type 1 Receptor to Phosphatidylinositol 3-Kinase
Authors: Zahradka Peter , Litchie Brenda , Storie Ben , Helwer Gail
Published: February 2004

Angiotensin II (AngII) activates phosphatidylinositol 3-kinase (PI3-kinase), a known effector of receptor tyrosine kinases. Treatment of smooth muscle cells with AngII has also been shown to promote phosphorylation of various tyrosine kinase receptors. We therefore investigated the relationship between AngII and IGF-I receptor activation in smooth muscle cells with a phosphorylation-specific antibody. Our experiments showed that IGF-I receptor phosphorylation was maximally stimulated within 10 min by AngII. Inclusion of an IGF-I-neutralizing antibody in the culture media did not prevent IGF-I receptor phosphorylation after AngII treatment, which argues that a paracrine/autocrine loop is not required. Furthermore, this process was blocked by losartan and 1-(1,1-dimethylethyl)-1-(4-methylphenyl)-1H-pyrazolo[3,4-d]pyrimidin-4-amine (PP-1), indicating stimulation of IGF-I receptor phosphorylation occurs via AngII type 1 receptor-dependent activation of Src kinase. The functional significance of IGF-I receptor transactivation was examined with selective inhibitors of the IGF-I receptor kinase (AG1024, AG538). When AngII-treated cells were incubated with AG1024 or AG538, phosphorylation of the regulatory p85 subunit of PI3-kinase was blocked. Furthermore, phosphorylation of the downstream factor p70S6K did not occur. In contrast, AG1024 did not prevent MAPK or Src kinase activation by AngII. AG1024 also did not inhibit AngII-dependent cell migration, although this process was blocked by inhibitors of the epidermal growth factor and platelet-derived growth factor receptors. Transactivation of the IGF-I receptor is therefore a critical mediator of PI3-kinase activation by AngII but is not required for stimulation of the MAPK cascade.
C. elegans pro-1activity is required for soma/germline interactions that influence proliferation and differentiation in the germ line
Authors: Killian Darrell J. , Hubbard E. Jane Albert
Published: February 2004

Strict spatial and temporal regulation of proliferation and differentiation is essential for proper germline development and often involves soma/germline interactions. In C. elegans, a particularly striking outcome of defective regulation of the proliferation/differentiation pattern is the Pro phenotype in which an ectopic mass of proliferating germ cells occupies the proximal adult germ line, a region normally occupied by gametes. We describe a reduction-of-function mutation in the gene pro-1 that causes a highly penetrant Pro phenotype. The pro-1 mutant Pro phenotype stems from defects in the time and position of the first meiotic entry during early germline development. pro-1(RNAi) produces a loss of somatic gonad structures and concomitant reduction in germline proliferation and gametogenesis. pro-1 encodes a member of a highly conserved subfamily of WD-repeat proteins. pro-1(+) is required in the sheath/spermatheca lineage of the somatic gonad in its role in the proper establishment of the proliferation/differentiation pattern in the germline. Our results provide a handle for further analysis of this soma-to-germline interaction.
Ihh signaling is directly required for the osteoblast lineage in the endochondral skeleton
Authors: Long Fanxin , Chung Ung-il , Ohba Shinsuke , McMahon Jill , Kronenberg Henry M. , McMahon Andrew P.
Published: February 2004

Indian hedgehog (Ihh) is indispensable for development of the osteoblast lineage in the endochondral skeleton. In order to determine whether Ihh is directly required for osteoblast differentiation, we have genetically manipulated smoothened (Smo), which encodes a transmembrane protein that is essential for transducing all Hedgehog (Hh) signals. Removal of Smo from perichondrial cells by the Cre-LoxP approach prevents formation of a normal bone collar and also abolishes development of the primary spongiosa. Analysis of chimeric embryos composed of wild-type and Smon/n cells indicates that Smon/n cells fail to contribute to osteoblasts in either the bone collar or the primary spongiosa but generate ectopic chondrocytes. In order to assess whether Ihh is sufficient to induce bone formation in vivo, we have analyzed the bone collar in the long bones of embryos in which Ihh was artificially expressed in all chondrocytes by the UAS-GAL4 bigenic system. Although ectopic Ihh does not induce overt ossification along the entire cartilage anlage, it promotes progression of the bone collar toward the epiphysis, suggesting a synergistic effect between ectopic Ihh and endogenous factors such as the bone morphogenetic proteins (BMPs). In keeping with this model, Hh signaling is further found to be required in BMP-induced osteogenesis in cultures of a limb-bud cell line. Taken together, these results demonstrate that Ihh signaling is directly required for the osteoblast lineage in the developing long bones and that Ihh functions in conjunction with other factors such as BMPs to induce osteoblast differentiation. We suggest that Ihh acts in vivo on a potential progenitor cell to promote osteoblast and prevent chondrocyte differentiation.
Bapx1 regulates patterning in the middle ear: altered regulatory role in the transition from the proximal jaw during vertebrate evolution
Authors: Tucker Abigail S. , Watson Robert P. , Lettice Laura A. , Yamada Gen , Hill Robert E.
Published: February 2004

The middle ear apparatus is composed of three endochondrial ossicles (the stapes, incus and malleus) and two membranous bones, the tympanic ring and the gonium, which act as structural components to anchor the ossicles to the skull. Except for the stapes, these skeletal elements are unique to mammals and are derived from the first and second branchial arches. We show that, in combination with goosecoid (Gsc), the Bapx1 gene defines the structural components of the murine middle ear.

During embryogenesis, Bapx1 is expressed in a discrete domain within the mandibular component of the first branchial arch and later in the primordia of middle ear-associated bones, the gonium and tympanic ring. Consistent with the expression pattern of Bapx1, mouse embryos deficient for Bapx1 lack a gonium and display hypoplasia of the anterior end of the tympanic ring. At E10.5, expression of Bapx1partially overlaps that of Gsc and although Gsc is required for development of the entire tympanic ring, the role of Bapx1 is restricted to the specification of the gonium and the anterior tympanic ring. Thus, simple overlapping expression of these two genes appears to account for the patterning of the elements that compose the structural components of the middle ear and suggests that they act in concert.

In addition, Bapx1 is expressed both within and surrounding the incus and the malleus. Examination of the malleus shows that the width, but not the length, of this ossicle is decreased in the mutant mice. In non-mammalian jawed vertebrates, the bones homologous to the mammalian middle ear ossicles compose the proximal jaw bones that form the jaw articulation(primary jaw joint). In fish, Bapx1 is responsible for the formation of the joint between the quadrate and articular (homologues of the malleus and incus, respectively) enabling an evolutionary comparison of the role of a regulatory gene in the transition of the proximal jawbones to middle ear ossicles. Contrary to expectations, murine Bapx1 does not affect the articulation of the malleus and incus. We show that this change in role of Bapx1 following the transition to the mammalian ossicle configuration is not due to a change in expression pattern but results from an inability to regulate Gdf5 and Gdf6, two genes predicted to be essential in joint formation.
Gbb/Bmp signaling is essential for maintaining germline stem cells and for repressingbamtranscription in theDrosophilatestis
Authors: Kawase Eihachiro , Wong Marco D. , Ding Bee C. , Xie Ting
Published: February 2004

Stem cells are responsible for replacing damaged or dying cells in various adult tissues throughout a lifetime. They possess great potential for future regenerative medicine and gene therapy. However, the mechanisms governing stem cell regulation are poorly understood. Germline stem cells (GSCs) in the Drosophila testis have been shown to reside in niches, and thus these represent an excellent system for studying relationships between niches and stem cells. Here we show that Bmp signals from somatic cells are essential for maintaining GSCs in the Drosophila testis. Somatic cyst cells and hub cells express two Bmp molecules, Gbb and Dpp. Our genetic analysis indicates that gbb functions cooperatively with dpp to maintain male GSCs, although gbb alone is essential for GSC maintenance. Furthermore, mutant clonal analysis shows that Bmp signals directly act on GSCs and control their maintenance. In GSCs defective in Bmp signaling,expression of bam is upregulated, whereas forced bamexpression in GSCs causes the GSCs to be lost. This study demonstrates that Bmp signals from the somatic cells maintain GSCs, at least in part, by repressing bam expression in the Drosophila testis. dpp signaling is known to be essential for maintaining GSCs in the Drosophila ovary. This study further suggests that both Drosophila male and female GSCs use Bmp signals to maintain GSCs.
Epidermal cells accelerate the restoration of the blood flow in diabetic ischemic limbs
Authors: Jiao Chunhua , Bronner Sarah , Mercer Keri L. N. , Sheriff Don D. , Schatteman Gina C. , Dunnwald Martine
Published: February 2004

Epidermal progenitor cells (EpPCs) were long thought to be unipotent, giving rise only to other keratinocytes but recent studies question this assumption. Here, we investigated whether mouse EpPCs can adopt other antigenic and functional phenotypes. To test this, we injected freshly isolated and cultured EpPCs and transient amplifying cells into diabetic and non-diabetic mouse ischemic hindlimb and followed the cells' fate and the recovery of the ischemic limb blood flow over time. Both freshly isolated and cultured EpPCs and transient amplifying cells were incorporated into the vasculature of the ischemic limb 2 and 5 weeks post-injection, and some expressed endothelial cell but not keratinocyte antigens. Additionally, in the non-diabetic animals, first transient amplifying cells and then EpPCs accelerated the restoration of the blood flow. By contrast, in diabetic animals, only injected EpPCs or unsorted epidermal cells accelerated the restoration of the blood flow. These data indicate that epidermal cells can adopt non-skin phenotypes and functions, and that this apparent pluripotency is not lost by differentiation of EpPCs into transient amplifying cells. They also suggest that epidermal cell therapy might be of therapeutic value in the treatment of diabetic ischemia. Finally, because epidermal cells are readily accessible and expandable, they appear to be ideally suited for use as a non-viral gene delivery therapy.