bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preparation and Characterization of an Acellular Bovine Pericardium Intended for Manufacture of Valve Bioprostheses
Authors: Goissis Gilberto , de Fátima Giglioti Aparecida , Braile Domingo Marcolino 
Published: May 2011

AbstractMajor problems with biological heart valves post‐implantation are associated with progressive structural deterioration and calcification attributed to glutaraldehyde processing, dead cells, and cell fragments present in the native tissue. In spite of these problems, glutaraldehyde still is the reagent of choice. The results with acellular matrix xenograft usually prepared by detergent treatment in association with enzymes are rather conflicting because while preserving mechanical properties, tissue morphology and collagen structure are process dependent. This work describes a chemical approach for the preparation of an acellular bovine pericardium matrix intended for the manufacture of heart valve bioprostheses. Cell removal was performed by an alkaline extraction in the presence of calcium salts for periods ranging from 6 to 48 h. The results showed that cell removal was achieved after 12 h, with swelling and negative charge increasing with processing time. Nevertheless, collagen fibril structure, ability to form fibrils, and stability to collagenase were progressive after 24‐h processing. There was no denaturation of the collagen matrix. A process is described for the preparation of acellular bovine pericardium matrices with preserved fibril structure and morphology for the manufacture of cardiac valve bioprostheses and may be used in other applications for tissue reconstruction.
Cardiovascular Simulator Improvement: Pressure Versus Volume Loop Assessment
Authors: Fonseca Jeison , Andrade Aron , Nicolosi Denys E.C. , Biscegli José F. , Leme Juliana , Legendre Daniel , Bock Eduardo , Lucchi Julio Cesar 
Published: May 2011

AbstractThis article presents improvement on a physical cardiovascular simulator (PCS) system. Intraventricular pressure versus intraventricular volume (PxV) loop was obtained to evaluate performance of a pulsatile chamber mimicking the human left ventricle. PxV loop shows heart contractility and is normally used to evaluate heart performance. In many heart diseases, the stroke volume decreases because of low heart contractility. This pathological situation must be simulated by the PCS in order to evaluate the assistance provided by a ventricular assist device (VAD). The PCS system is automatically controlled by a computer and is an auxiliary tool for VAD control strategies development. This PCS system is according to a Windkessel model where lumped parameters are used for cardiovascular system analysis. Peripheral resistance, arteries compliance, and fluid inertance are simulated. The simulator has an actuator with a roller screw and brushless direct current motor, and the stroke volume is regulated by the actuator displacement. Internal pressure and volume measurements are monitored to obtain the PxV loop. Left chamber internal pressure is directly obtained by pressure transducer; however, internal volume has been obtained indirectly by using a linear variable differential transformer, which senses the diaphragm displacement. Correlations between the internal volume and diaphragm position are made. LabVIEW integrates these signals and shows the pressure versus internal volume loop. The results that have been obtained from the PCS system show PxV loops at different ventricle elastances, making possible the simulation of pathological situations. A preliminary test with a pulsatile VAD attached to PCS system was made.
In vivo neutralization of anti‐A and successful transfusion of A antigen–incompatible red blood cells in an animal model
Authors: Oliver Caroline , Blake Deborah , Henry Stephen 
Published: May 2011

BACKGROUND: Our aim was to determine if the historical principle of Lewis glycolipid neutralization of antibody and subsequent Lewis‐incompatible transfusion could be extended and applied to the ABO blood group system using synthetic glycolipid‐like constructs.STUDY DESIGN AND METHODS: In vitro experiments with human blood and blood group A function‐spacer‐lipid constructs (FSL‐A) were used to determine rates and concentrations that caused antigen transformation and anti‐A neutralization. FSL‐A constructs were intravenously infused into naive and anti‐A–immunized mice to determine in vivo antigen transformation, anti‐A inhibition, and tolerance to A antigen–incompatible transfusions (A+biotin kodecytes).RESULTS: FSL‐A was able to cause in vivo transformation of circulating mouse cells into A antigen–positive cells (in vivo A kodecytes) without consequence in animals either with or without circulating anti‐A. FSL‐A was able to neutralize circulating anti‐A and allow for successful transfusion of incompatible A kodecytes. In the absence of FSL‐A neutralization incompatible cells were rapidly destroyed.CONCLUSIONS: FSL constructs have the potential to neutralize circulating antibodies and allow for, or mitigate, the consequences of ABO‐incompatible red blood cell transfusion.
The Participation Paradox of Indigenous Autonomy in Mexico
Authors: Hiskey Jonathan T. , Goodman Gary L. 
Published: May 2011

AbstractAs indigenous movements around the world seek to strengthen their collective voice in their respective political systems, efforts continue to design political institutions that offer both sufficient local autonomy and incentives to participate in the broader political system. The state of Oaxaca, Mexico, offers a test case of one such effort at indigenous-based institutional design. This article argues that such reforms often fail to confront the tension between local autonomy and citizen engagement in politics outside the borders of the community. Testing this theory through a comparative analysis of voter turnout rates in municipalities across the state of Oaxaca and the neighboring state of Guerrero, this study finds that the adoption of indigenous institutions at the local level is associated with significantly lower voter turnout rates for national elections.
A geographic comparison of pseudogamous populations of the fall cankerworm (Alsophila pometaria)
Authors: Mitter C. , Neal J. W. , Gott K. M. , Silverfine E. 
Published: May 2011

AbstractPhenological and genetic observations were made during two outbreak seasons on a population of the fall cankerworm, Alsophila pometaria Harris (Lepidoptera, Geometridae), at Beltsville, Maryland, U.S.A. As in intensively‐studied populations 300 km to the northeast on Long Island, New York, this population consisted mostly of asexual females requiring conspecific mating to reproduce. The estimated fraction of outcrossing (15–20%), however, was several times that typical for Long Island. Numerous intersexes were found, concentrated in a few families, suggesting that pseudogamy is controlled by more than one heritable factor. The genetic diversity and ecological heterogeneity among asexual females in the Maryland population appear similar to that on Long Island, but there is little overlap in common asexual genotypes. Electromorph frequencies at three loci in males, by contrast, show little geographic variation. The adult activity period is later and longer in Maryland than in colder parts of the range.RésuméComparaison de population géographiques d'Alsophila pometariaAu cours d'une pullulation d'Alsophila pometaria, à Beltsville, Maryland, U.S.A., nous avons contrǒlé les émergences des papillons pendant deux saisons, échantillonné les sexes et les génotypes par électrophorèse pour quatre loci, puis nous avons examiné l'héritabilité de ces marqueurs électropho‐rétiques dans la descendance élevée au laboratoire. Comme pour les populations étudiées avec précision à 300 km au N.E à Long Island, New York, cette population comprenait essentiellement des femelles asexuées exigeant des accouplements conspécifiques pour se reproduire. Environ 15% de la descendance examinée présentait une ségrégation, contre 5% ou moins à Long Island. De nombreux intersexués élevés à partir des populations de Maryland et de New York, se trouvaient uniquement dans quelques lignées, ceci suggère que le rejet des spermatozoïdes et la diploïde des oeufs qui caractérise la pseudogamie, ont des déterminismes génétiques séparés. La diversité des femelles asexuées de la population de Beltsville, dominée par quatre génotypes asexués, paraǐt semblable à celle de Long Island, mais les clones similaires se chevauchent très peu. Par contre, les fréquences allèliques de tois loci sont presque identiques chez les mǎles de deux localités. Les fréquences génétiques des chenilles diffèrent pour des échantillons prélevés à quelques kilomètres de distance sur des hǒtes différents dans la měme population; il en est de měme pour des femelles prélevées a différentes époques. Tout ceci suggère une hétérogénéité écologique parmi les clones, comme cela a été suggéré pour Long Island. La période d'activité des adultes est plus tardive, plus marquée et plus longue au Maryland que dans les parties les plus froides de l'aire; elle s'étend de décembre à mars, avec les captures les plus fortes en janvier et février.
Metabolic costs of mixed‐function oxidase induction in Heliothis zea
Authors: Neal J. J. 
Published: May 2011

AbstractThe maximum metabolic cost of microsomal mixed‐function oxidase (MFO) induction was measured in terms of food utilization parameters. MFOs in larvae of Heliothis zea (Boddie) (Lepidoptera: Noctuidae) were induced by feeding on diet containing indole 3‐carbinol (I3C). Growth, food utilization parameters, cytochrome P‐450 content and O‐demethylase activity of these larvae were compared to larvae reared on the same diet without I3C. Three‐fold to nine‐fold greater O‐demethylase activity and seven‐fold more cytochrome P‐450 were measured in larvae fed I3C, but no differences were detected in the food utilization and growth parameters. These results do not support the view that costs of MFO induction may be responsible for differences in food utilization parameters.RésuméCoǔts métaboliques de l'induction de la fonction oxydase mixte chez Heliothis zeaLe coǔt métabolique maximum de l'induction de la fonction oxydase mixte microsomale (MFO) a été évalué au moyen de paramètres caractérisant l'utilisation de l'aliment. Les MFO des chenilles d'H. zea ont été induites en les élevant avec un régime contenant 0,2 % d'indole 3‐carbinol (I3C) en poids/poids humide. L'induction a été mise en évidence en mesurant l'O‐deméthylation du p‐nitroanisole par les microsomes de l'intestin des larves des 4ème et 5ème stades, et la teneur en cytochrome P‐450 (mesurée par les différences des spectres de l'oxyde de carbone) des microsomes de l'intestin des larves du 5ème stade élevées avec I3C et témoins. La digestibilité approchée, l'efficacité de la conversion de l'aliment digéré et l'efficacité de la conversion de l'aliment ingéré (évaluée d'après la durée de développement larvaire de la néonate à la prénymphe), le temps pour atteindre le stade prénymphe, le poids final, on été comparés chez les témoins et chez les chenilles élevées sur I3C. Les chenilles élevées sur I3C ont présenté une activité O‐deméthylase 3 à 2 fois supérieure et 7 fois plus de cytochrome P‐450, mais aucune différence n'a pu ětre décelée pour les paramètres d'utilisation alimentaire et de croissance. Ces résultats ne confirment pas l'hypothèse suivant laquelle le coǔt de l'induction de MFO pourraǐt ětre responsable de différences dans les paramètres de l'utilisation de l'aliment.
Self and conspecific superparasitism by the egg parasitoid Trichogramma evanescens
Authors: van Dijken Marianne J. , Waage Jeffrey K. 
Published: May 2011

AbstractSuperparasitism is a widespread phenomenon in insect parasitoids and may be advantageous in certain circumstances. In this paper, we distinguish two kinds of superparasitism with different adaptive consequences for an ovipositing parasitoid: self superparasitism, where a parasitoid oviposits in a host in which she has previously oviposited, and conspecific superparasitism, where she oviposits in a host containing egg(s) from a previous oviposition by a conspecific. Our studies on Trichogramma evanescens Westwood show that females lay smaller clutches on parasitized than on healthy hosts but make the same overall allocation of males and females, although the sequence of sexes during oviposition differs. No difference was found between allocation in self and conspecific superparasitism. These results are discussed in the light of theories for progeny and sex allocation.ZusammenfassungSelbst‐ und Konspezifisch‐Superparasitismus durch die Schlupfwespe Trichogramma evanescensSuperparasitismus ist ein weitverbreitetes Phänomen in Parasitoiden von Insekten und es kann unter bestimmten Umständen vorteilhaft sein. Diese Arbeit macht Unterschied zwischen zwei Formen von Superparasitismus, jeder mit seiner eigenen adaptiven Konsequenz für die parasitierende Schlupfwespe: Selbst‐Superparasitismus, wenn eine Schlupfwespe einen Wirt parasitiert die sie vorher selbst parasitiert hat, und Konspezifisch‐Superparasitismus, wenn sie einen Wirt parasitiert die vorher von einem Artgenossen parasitiert worden ist. Unsere Untersuchungen an Trichogramma evanescens zeigen dass die Weibchen auf den belegten Wirten kleinere Gelege haben als auf den gesunden Wirten, aber das Gesamtverhältnis von männlichen und weiblichen Brut ist dasselbe, obschon die Reihenfolge in den die Eier der beiden Geschlechte abgelegt werden sich underscheiden. Keinen Unterschied wurde gefunden zwischen die Ablegung während Selbst‐Superparasitismus und Konspezifisch‐Superparasitismus. Diese Ergebnisse werden diskutiert im Rahmen der Theorien für die Belegung des Wirtes in bezug auf die Anzahl und das Geschlecht der Eier.
Egg‐laying strategy under natural conditions of Leptopilina boulardi, a hymenopteran parasitoid of Drosophila spp
Authors: Carton Y. , Chibani F. , Haouas S. , Marrakchi M. 
Published: May 2011

AbstractThe hypothesis of optimal host species selection predicts that when a parasitoid has the choice between two host species, it will choose the species that gives the best survival chances for its progeny. We confirmed this hypothesis by laboratory experiments with Leptopilina boulardi Barb. et al., a cynipid parasitoid which prefers Drosophila melanogaster Meigen (the host species most suitable for parasitoid survival) above D. simulans Sturt. As far as fitness parameters are concerned, the fertility of L. boulardi is higher with D. melanogaster, the egg laying can be spread out over a long period when this host is relatively scarce. This does not occur with D. simulans in which parasitic oviposition stops soon when this host is not abundant.Investigations of this foraging strategy were done under more complex natural conditions. We found that L. boulardi has a type III functional response with D. melanogaster only; furthermore, it seems that a switching effect may exist with this host. Parasitoid females appear to distribute their eggs more regularly on D. melanogaster, thus avoiding superparasitism. This seems to be independent of the relative frequency of this host. However, superparasitism of D. simulans did occur more frequently when this host was scarce.RésuméStratégie de ponte de Leptopilina boulardi (Hyménoptère parasite de drosophiles) dans les conditions naturellesLe concept de réponse optimale d'un parasite vis‐à‐vis de l'hǒte le plus favorable pour son développement demeure surtout théorique et n'a pu ětre vérifié que dans les conditions de laboratoire. Nous avons montré que Drosophila melanogaster s'avère ětre, par rapport à D. simulans, l'hǒte le plus favorable pour le développement du cynipide parasite Leptopilina boulardi. Une étude sur le terrain a démontré que ce parasite présente une réponse fonctionnelle densité dépendante vis‐à‐vis de D. melanogaster et non vis‐à‐vis de D. simulans, avec un effet de bascule. D'autre part, il s'avère que ce parasite exploite beaucoup mieux son hǒte, en évitant le superparasitisme, ceci étant démontré au laboratoire et dans la nature. Enfin, il apparaǐt qu'il est capable d'allonger sa période de ponte lorsque cet hǒte est rare, ce qui ne se produit pas avec D. simulans.
Midkine expression in oral squamous cell carcinoma and leukoplakia
Authors: Jham Bruno Correia , Costa Nadia Lago , Silva Janine Mayra , de Miranda Alessandra Castro , Oliveira Jose Carlos , Silva Tarcília Aparecida , Batista Aline Carvalho 
Published: May 2011

J Oral Pathol Med (2012) 41: 21–26Background:  Midkine (MK), a 13‐kDa heparin‐binding growth factor, is overexpressed in various human cancers. However, its role in the development and progression of oral cavity squamous cell carcinoma (OCSCC) is still unclear. Thus, the aim of this study was to evaluate the expression of MK in samples of OCSCC, leukoplakia, and healthy oral mucosa (control).Methods:  Surgically excised specimens from patients with primary OCSCC (n = 28) were immunostained for MK, Ki‐67, PCNA, p53, bcl‐2, Bax, and CD31. Besides this, MK expression was also investigated in leukoplakia and normal oral mucosa. The relationship of MK+ cells with clinical parameters (tumor location, tumor size, lymph node metastasis, and survival) and microscopic parameters (WHO histological grading, intensity of inflammation, proliferation index, apoptosis, and angiogenesis) was also evaluated.Results:  The results showed that MK expression was increased in OCSCC in relation to leukoplakia and normal mucosa. Furthermore, MK expression was increased in late‐stage tumors (T3/T4) compared with early‐stage lesions (T1/T2). MK‐positive lesions also showed increased expression of the anti‐apoptotic protein bcl‐2.Conclusion:  OCSCC, particularly late‐stage tumors, exhibits increased MK expression, which may be involved in tumor progression via upregulation of anti‐apoptotic genes, as shown by the augmented bcl‐2 positivity in MK‐positive tumors.
Effect of Smoking Habits on Accuracy of Implant Placement Using Mucosally Supported Stereolithographic Surgical Guides
Authors: D'haese Jan , De Bruyn Hugo 
Published: May 2011

ABSTRACTBackground: Smoking is considered as a factor for implant survival and peri‐implant bone loss of dental implants. Several studies revealed the negative effect of smoking on osseointegration and its dose‐related effect.Purpose: To evaluate the effect of smoking habits on accuracy of implant placement using mucosally supported stereolithographic surgical guides.Material and Methods: Six OsseoSpeed™ implants (Astra Tech AB, Mölndal, Sweden) were inserted into the maxilla in 13 patients. Patients were excluded if they suffered from any systemic disease or if they were actually taking any kind of medication. Software (Mimics® 9.0) was used to fuse images of the virtually planned and actually placed implants, and locations and axes were compared between the nonsmoking and smoking subgroups. As the mucosal biotype could probably influence accuracy data, 12 reference points were defined within each patient to define a mean mucosal thickness value.Results: In the smoking subgroup, 36 implants were placed compared with 42 in the nonsmoking subgroup. Mean coronal deviation was 1.04 mm (range: 0.29–2.45 mm) among the smokers compared with 0.80 mm among the nonsmokers (range: 0.29–1.67 mm). At apical point, mean deviation was 1.26 mm (range: 0.39–3.01 mm) among the smokers compared with 1.02 mm among the nonsmokers (range: 0.32–2.59 mm). Mean angular deviation was 2.64° (range: 0.41–6.81°) among the smokers compared with 2.57° among the nonsmokers (range: 0.16°–8.86°). Significant differences were found when comparing global coronal and apical deviation between the smokers and the nonsmokers (p < .05). Evaluating mucosal thickness, mean value was 3.19 mm (range: 2.39–4.01 mm) among the smokers compared with 2.43 mm among the nonsmokers (range: 1.44–3.03 mm).Conclusions: Statistically significant differences were found when comparing the accuracy of dental implant placement of the smokers with the nonsmokers. Smokers have significant thicker supporting mucosal tissues compared with nonsmokers, which may explain inaccuracy due to less stability of the surgical guide or the scanning prosthesis.
A Quantitative Meta-Analysis on Cue-Induced Male Sexual Arousal
Authors: Kühn Simone , Gallinat Jürgen 
Published: May 2011

ABSTRACT

Introduction
Visually induced sexual arousal is a common occurrence in human behavior. The cerebral underpinnings of this response have been explored in recent neuroimaging studies.

Aim
We set out to test the strength of evidence for the presence of a core network of brain regions involved in male sexual arousal elicited by erotic stimuli.

Methods
Eleven functional magnetic resonance imaging studies that presented erotic visual stimuli and compared the associated brain activity with the brain activity elicited by neutral visual stimuli were identified.

Main Outcomes Measures
Activation likelihood estimation was employed to perform quantitative meta-analyses on coordinates of brain activation in order to assess significant concordance across studies.

Results
The meta-analysis included studies on heterosexual males and revealed consistent activation in the hypothalamus, thalamus, amygdala, anterior cingulate gyrus (ACC), insula, fusiform gyrus, precentral gyrus, parietal cortex, and occipital cortex across studies. Moreover, we explored brain responses associated with a physiological marker of sexual arousal (penile tumescence) and found concurrence in hypothalamus, thalamus, bilateral insula, ACC, postcentral gyrus, and occipital gyrus.

Conclusions
This is the first quantitative meta-analysis on sexual cue reactivity and identifies a neural network consisting of cognitive (parietal cortex, ACC, thalamus, insula), emotional (amygdala, insula), motivational (precentral gyrus, parietal cortex), and physiological (hypothalamus/thalamus, insula) components constituting a core circuit of male sexual arousal in humans.
Involvement of Matrix Metalloproteinase‐2 in the Development of Medial Layer Vascular Calcification in Uremic Rats
Authors: Kumata Chiaki , Mizobuchi Masahide , Ogata Hiroaki , Koiwa Fumihiko , Kondo Fumiko , Kinugasa Eriko , Akizawa Tadao 
Published: May 2011

AbstractVascular calcification is the most important cause of cardiovascular disease in patients with chronic kidney disease (CKD). Medial layer vascular calcification, which is recognized to be an active process (i.e. the transformation of vascular smooth muscle cells into osteoblast‐like cells), is common in CKD patients. We have recently reported the possibility of an interaction between elastin degradation and medial layer vascular calcification. Matrix metalloproteinase‐2 (MMP‐2), which induces the degradation of elastin, has been implicated in the elastic calcification in arteries of dialysis patients; however, the precise mechanisms by which elastin degradation interacts with the development of vascular calcification remain to be studied. To clarify the mechanisms by which elastin degradation is involved in the development of medial layer vascular calcification in the uremic milieu, we induced aortic medial layer calcification in 5/6 nephrectomized uremic rats (male Sprague–Dawley rats) fed a diet containing high phosphate (1.2%) and lactate (20%). After 10 weeks, the rats were euthanized for the measurement of serum chemistry profiles and histological analyses. The uremic rats showed significant increases in blood pressure, serum creatinine, phosphate, and parathyroid hormone levels compared with normal rats. Von Kossa staining showed medial layer aortic calcification in the uremic rats. In calcified lesions, thin elastic lamellae were observed by elastin staining, indicating that elastin degradation could occur in the area. Furthermore, MMP‐2 expression determined by immunohistochemistry was also observed in the same area. Elastin degradation accompanied by MMP‐2 expression might be involved in the development of medial layer vascular calcification in uremic rats.