636 resultados para Childs, Eber.


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The scope and significance of human conflicts with urban and suburban Canada goose populations has been growing rapidly since the mid 1980s. A lack of basic understanding about the biology and ecology of locally abundant goose populations has led, in part, to argument between opposing camps over the appropriate approaches and methodologies to resolve human-goose conflicts. Animal welfare interests have focused on the humaneness of roundup and slaughter programs, and advocated non-lethal approaches coupled with what they view as the more benign population control activity of egg addling. Some traditional wildlife managers have argued that non-lethal approaches have been tried and have failed, and that procedures such as addling do not work quickly or effectively. Differences have led to legal confrontations that absorb considerable energy and effort and may make cooperative involvement more difficult. This paper articulates some of the arguments that comprises the basis for the perspective of animal welfarists. It ends with a call for greater cooperation and involvement between all interests concerned with Canada geese.

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DEP domain-containing mTOR-interacting protein (DEPTOR) inhibits the mechanistic target of rapamycin (mTOR), but its in vivo functions are unknown. Previous work indicates that Deptor is part of the Fob3a quantitative trait locus (QTL) linked to obesity/leanness in mice, with Deptor expression being elevated in white adipose tissue (WAT) of obese animals. This relation is unexpected, considering the positive role of mTOR in adipogenesis. Here, we dissected the Fob3a QTL and show that Deptor is the highest-priority candidate promoting WAT expansion in this model. Consistently, transgenic mice overexpressing DEPTOR accumulate more WAT. Furthermore, in humans, DEPTOR expression in WAT correlates with the degree of obesity. We show that DEPTOR is induced by glucocorticoids during adipogenesis and that its overexpression promotes, while its suppression blocks, adipogenesis. DEPTOR activates the proadipogenic Akt/PKB-PPAR-gamma axis by dampening mTORC1-mediated feedback inhibition of insulin signaling. These results establish DEPTOR as a new regulator of adipogenesis.

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Cancer-prone genetic disorders are responsible for brain tumors in a considerable proportion of children. Additionally, rare genetic syndromes associated to cancer development may potentially disclose genetic mechanisms related to oncogenesis. We describe two pediatric patients with encephalocraniocutaneous lipomatosis (ECCL), a very rare genetic syndrome with around 60 reported cases, which developed low-grade astrocytoma at 3 and 12 years of age. Patients with ECCL seem to be at risk of benign forms of osseous tumors such as ossifying fibromas, odontomas, and osteomas. The association between brain tumor and ECCL was previously reported only once, in a pediatric case of a mixed neuronal-glial histology. Whether ECCL may be a genetic condition of predisposing brain tumor in children strongly needs to be addressed.

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Objective Epidermoid cysts of the cerebellopontine angle (CPA) can be a surgical challenge for the pediatric neurosurgeon. Ideally, total removal must be achieved; however, occasional adhesions of these tumors to vital neurovascular structures and extension far beyond the midline may preclude their total removal. The aims of this article are to present an alternative surgical approach to these lesions and to provide the rationale for this technique. Material and methods A 16-year-old boy was admitted to our pediatric neurosurgery department with a 1-year history of nonspecific headaches. His neurological examination showed right-sided dysmetria and gait ataxia. Magnetic resonance scans showed a space-occupying lesion on the right CPA with low intensity on T-1-weighted images and high intensity on T-2-weighted images. Results Craniotomy for tumor excision via pre- and subtemporal transtentorial approach was performed disclosing a 3.5 x 3 x 2.8-cm(3) well-encapsulated tumor, which was confirmed to be an epidermoid cyst. The postoperative course was uneventful. Conclusions A combined pre- and subtemporal approach utilizes a wide opening of the tentorium and the option of supratentorial retraction of the cerebellum to provide an excellent angle of approach to CPA lesions involving the anterolateral aspect of the brain stem in children.

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The main purposes of this manuscript are to provide an overview of various modalities of surgical correction of anterior plagiocephaly and to emphasize their differences with the classic open frontal-orbital advancement. Advancement of technology provides development of many other ways to achieve the same results. The authors describe the classic open frontal-orbital advancement and compare with other proposed techniques for correction of frontal plagiocephaly. The main limitation of the use of new forms of treatment of the anterior plagiocephaly is the age of the patient. There is still no consensus on criteria for quantitative evaluation of surgical results, and new forms of treatment do not present results with long follow-up. Frontal-orbital advancement is the preferred procedure to correct unicoronal synostosis due to its universal indication regardless of the age and degree of deformation of the anterior plagiocephaly.

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Background Perimedullary arteriovenous fistulas (PMAVFs) are rare spinal lesions and even more uncommon in children. Objective The aim of this study was to document rare occurrences of this type of arteriovenous malformation in six children treated at our institution. Methods The clinical data, radiological findings, and treatment in six cases of PMAVFs were reviewed. Six patients with PMAVFs were managed at our institution over a 5-year period. The patients (four girls and two boys), ranging in age from 6 to 15 years, presented with initially fluctuating, and eventually permanent and progressive, sudden-onset paraparesis, sensory disturbances, and sphincter dysfunction. The duration of symptoms before diagnosis ranged from 1 week to 13 years. Results All the patients underwent magnetic resonance imaging and spinal selective angiography, which demonstrated the characteristic imaging of an arteriovenous fistula. Embolization of the arteriovenous fistula was initially attempted in three patients with successful occlusion of the fistula in two. For the remaining cases, open surgery was performed, with complete occlusion of the fistula. There was no morbidity, regardless of the treatment performed. All the patients experienced neurological improvement after treatment. Conclusions No specific clinical or radiological characteristic of PMAVFs in the pediatric population was observed when our series was compared with a general series. Early diagnosis and timing of the therapeutic intervention seemed to avoid the development of irreversible ischemic myeloradiculopathy and prevented hemorrhage. Treatment for PMAVFs is difficult to standardize because these are extremely rare lesions with different angioarchitecture configurations.

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Toxosplasma gondii is the model parasite of the phylum Apicomplexa, which contains numerous obligate intracellular parasites of medical and veterinary importance, including Eimeria, Sarcocystis, Cryptosporidium, Cyclospora, and Plasmodium species. Members of this phylum actively enter host cells by a multistep process with the help of microneme protein (MIC) complexes that play important roles in motility, host cell attachment, moving junction formation, and invasion. T. gondii (Tg)MIC1-4-6 complex is the most extensively investigated microneme complex, which contributes to host cell recognition and attachment via the action of TgMIC1, a sialic acid-binding adhesin. Here, we report the structure of TgMIC4 and reveal its carbohydrate-binding specificity to a variety of galactose-containing carbohydrate ligands. The lectin is composed of six apple domains in which the fifth domain displays a potent galactose-binding activity, and which is cleaved from the complex during parasite invasion. We propose that galactose recognition by TgMIC4 may compromise host protection from galectin-mediated activation of the host immune system.

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Background: The Maternal-Child Pastoral is a volunteer-based community organization of the Dominican Republic that works with families to improve child survival and development. A program that promotes key practices of maternal and child care through meetings with pregnant women and home visits to promote child growth and development was designed and implemented. This study aims to evaluate the impact of the program on nutritional status indicators of children in the first two years of age. Methods: A quasi-experimental design was used, with groups paired according to a socioeconomic index, comparing eight geographical areas of intervention with eight control areas. The intervention was carried out by lay health volunteers. Mothers in the intervention areas received home visits each month and participated in a group activity held biweekly during pregnancy and monthly after birth. The primary outcomes were length and body mass index for age. Statistical analyses were based on linear and logistic regression models. Results: 196 children in the intervention group and 263 in the control group were evaluated. The intervention did not show statistically significant effects on length, but point estimates found were in the desired direction: mean difference 0.21 (95%CI −0.02; 0.44) for length-for-age Z-score and OR 0.50 (95%CI 0.22; 1.10) for stunting. Significant reductions of BMI-for-age Z-score (−0.31, 95%CI −0.49; -0.12) and of BMI-for-age > 85th percentile (0.43, 95%CI 0.23; 0.77) were observed. The intervention showed positive effects in some indicators of intermediary factors such as growth monitoring, health promotion activities, micronutrient supplementation, exclusive breastfeeding and complementary feeding. Conclusions: Despite finding effect measures pointing to effects in the desired direction related to malnutrition, we could only detect a reduction in the risk of overweight attributable to the intervention. The findings related to obesity prevention may be of interest in the context of the nutritional transition. Given the size of this study, the results are encouraging and we believe a larger study is warranted.

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Abstract Background Disparities in utilization of oral healthcare services have been attributed to socioeconomic and individual behavioral factors. Parents’ socioeconomic status, demographics, schooling, and perceptions of oral health may influence their children’s use of dental services. This cross-sectional study assessed the relationships between socioeconomic and psychosocial factors and the utilization of dental health services by children aged 1–5 years. Methods Data were collected through clinical exams and a structured questionnaire administered during the National Day of Children’s Vaccination. A Poisson regression model was used to estimate prevalence ratios and 95% confidence intervals. Results Data were collected from a total of 478 children. Only 112 (23.68%) were found to have visited a dentist; 67.77% of those had seen the dentist for preventive care. Most (63.11%) used public rather than private services. The use of dental services varied according to parental socioeconomic status; children from low socioeconomic backgrounds and those whose parents rated their oral health as “poor” used dental services less frequently. The reason for visiting the dentist also varied with socioeconomic status, in that children of parents with poor socioeconomic status and who reported their child’s oral health as “fair/poor” were less likely to have visited the dentist for preventive care. Conclusion This study demonstrated that psychosocial and socioeconomic factors are important predictors of the utilization of dental care services.

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This thesis contains four different studies on the dynamics of gender in households and workplaces. The relationship between family life and work life is in focus, particularly in the paper on labour market outcomes after divorce. In the introductory chapter, the Swedish context is briefly described. The description focuses on gender differences in the labour market and in the home. Theories concerning the division of work in the household are discussed, as are two theories on labour market discrimination, viz. taste discrimination and statistical discrimination. The theory part is concluded with a discussion of social closure processes and gendered organizational structures. The Reproduction of Gender. Housework and Attitudes Towards Gender Equality in the Home Among Swedish Boys and Girls. The housework boys and girls age 10 to 18 do, and their attitudes towards gender equality in the home are studied. One aim is to see whether the work children do is gendered and if so, whether they follow their parents’, often gendered, pattern in housework. A second aim is to see whether parents’ division of work is related to the children’s attitude towards gender equality in the home. The data used are taken from the Swedish Child Level of Living Survey (Child-LNU) 2000. Results indicate that girls and boys in two-parent families are more prone to engage in gender-atypical work the more their parent of the same sex engages in this kind of work. The fact that girls still do more housework than boys indicates that housework is gendered work also among children. No relation between parents’ division of work and the child’s attitude towards gender equality in the home was found. Dependence within Families and the Household Division of Labor – A Comparison between Sweden and the United States. This paper assesses the relative explanatory value of the resource-bargaining perspective and the doing-gender approach in analysing the division of housework in the United States and Sweden from the mid-1970s to 2000. Data from the Swedish Level of Living Survey (LNU) and the Panel Study of Income Dynamics (PSID) were used. Overall results indicate that housework is truly gendered work in both countries during the entire period. Even so, the results also indicate that gender deviance neutralization is more pronounced in the United States than in Sweden. Unlike Swedish women, American women seem to increase their time spent in housework when their husbands are to some extent economically dependent on them, as if to neutralize the presumed gender deviance. Divorce and Labour Market Outcomes. Do Women Suffer or Gain? In this paper, the interconnected nature of work and family is studied by looking at labour market outcomes after divorce. The data used are retrospective work and family histories collected in LNU 1991. A hazard regression model with competing risks reveals that women’s chances of improving their occupational prestige appear to be better after divorce compared to before. Increased working hours and perhaps also increased energy invested in the job may pay off in better occupational opportunities. Worth noting, however, is that the outcome among women with a less firm labour market attachment is more often to a job of lower prestige than one of higher prestige. Hence, the labour market outcome for women after divorce is to some extent conditioned by their labour market attachment at the time of divorce. Men, on the other hand, in most cases seem to suffer occupationally from divorce. For separated men the risk of negative changes in occupational prestige is greater than for cohabiting men. Formal On-the-job Training. A Gender-Typed Experience and Wage- Related Advantage? Formal on-the-job training (FOJT) can have a positive impact on wages and on promotion opportunities. According to theory and earlier research, a two-step model of gender inequality in FOJT is predicted: First, women are less likely than men to take part in FOJT and, second, once women do get the more remunerative training, they are not rewarded for their new skills to the same extent as men are. Pooled cross-sectional data from the Swedish Survey of Living Conditions (ULF) in the mid-nineties were used. Results show that women are significantly less likely than men to take part in FOJT. Among those who do receive training, women are more likely to take part in industry-specific training, whereas men are more likely to participate in general training and training that increases promotion opportunities. The two latter forms of training significantly raise a man’s annual earnings but not a woman’s. Hence, the theoretical model is supported and it is argued that this gender inequality is partly due to employers’ discriminatory practices.

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[ES] Bajo una adaptación del Child´s Report of Parent Behavior Inventory (CRPBI) de Schaefer (1965) a población española realizada en diferentes centros educativos de la Comunidad Valenciana presentamos este trabajo. El CRPBI es un instrumento que al igual que el Parental Bonding instrument (PBI) permite evaluar la disciplina familiar que perciben sus hijos, tanto en la relación con el padre, como con su relación con su madre. El estudio se centra en una muestra de 23 menores, todos varones, de los que 17 son Menores con Medidas Judiciales (MMJ) internados en un centro perteneciente a la Comunidad Autónoma Canaria y el resto, 6, son menores en Situación de Riesgo (MR) los cuales residen en un barrio de la Ciudad de Las Palmas de Gran Canaria. Los resultados obtenidos muestran diferencias en las valoraciones que el menor hace sobre la relación con su padre y con su madre y como estos han percibido unas pautas de crianza que están centradas en el control, en la autonomía -entendida como estimulo de la sociabilidad- en el amor y en la hostilidad. Por un lado, de los progenitores de los menores adolescentes con medidas judiciales y por otro lado, de los menores en situación de riesgo ponen de manifiesto en el CRPBI que no hay una concordancia total entre los factores que describen las respuestas acerca de las relaciones con la madre y entre los factores que agrupan las relaciones con el padre, resultado que viene a avalar o a confirmar los resultados de estudios recientes sobre el tema que muestran diferencias en las valoraciones que el hijo hace sobre su relación con el padre y con la madre (Canamás, 2003; Rodrigo, 2004 y Tur, 2003).

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Extensive literature outlined that the quality of the mother-foetus relationship is considered the main feature with regard to the quality of postnatal mother-infant interaction and also to the child’s psychical development. Nowadays the relationship between the pregnant woman and her foetus is viewed as the central factor of the somatic dialogue between the functioning of the maternal and the foetal organisms. This dialogue is responsible for the physic development of the child, as well as of its psychosomatic structure. Therefore the research area has necessarily had to extend to the analysis of psychological processes concerning: the pregnancy, the couple that is bound by parenthood, the influence of intergenerational dynamics. In fact, the formation of maternal identity, as well as that of the relationship between the woman and the foetus, refers to the pregnant woman’s relationship with her parents, especially with her mother. The same pregnancy, considered as a psychosomatic event, is directly influenced by relational, affective and social factors, particularly by the quality of the interiorized parental relations and the quality of the current relationships (such as that with her partner and with her family of origin). Some studies have begun to investigate the relationship between the pregnant woman and the foetus in term of “prenatal attachment” and its relationship with socio-demographic, psychological e psychopathological aspects (such as pre and post partum depression), but the research area is still largely unexplored. The present longitudinal research aimed to investigate the quality of the pregnant womanfoetus relationship by the prenatal attachment index, the quality of the interiorized relationship with woman’s parents, the level of alexithymic features and maternity social support, in relation with the modulation of the physiology of delivery and of postpartum, as well as of the physical development of the child. A consecutive sample of 62 Italian primipara women without any kind of pathologies, participated in the longitudinal study. In the first phase of this study (third trimester of the pregnancy), it has investigated the psychological processes connected to the affective investment of the pregnant women towards the unborn baby (by Prenatal Attachment Inventory), the mothers’ interiorized relationship with their own parents (by Parental Bonding Instrument), the social and affective support from their partner and their family of origin are able to supply (by Maternity Social Support Scale), and the level of alexithymia (by 20-Toronto Alexithymia Scale). In the second phase of this study, some data concerning the childbirth course carried out from a “deliverygram” (such as labour, induction durations and modalities of delivery) and data relative to the newborns state of well-being (such as Apgar and pH indexes). Finally, in the third phase of the study women have been telephoned a month after the childbirth. The semistructured interview investigated the following areas: the memory concerning the delivery, the return to home, the first interactions between the mother and the newborn, the breastfeeding, the biological rhythms achieved from newborns. From the data analysis a sample with a good level of prenatal attachment and of support social and a good capability to mental functioning emerged. An interesting result is that the most of the women have a great percentage of “affectionless control style” with both parents, but data is not sufficient to interpret this result. Moreover, considering the data relative to the delivery, medical and welfare procedures, that have been necessary, are coherent with the Italian mean, while the percentage of the caesarean section (12.9%) is inferior to the national percentage (30%). The 29% of vaginal partum has got epidural analgesia, which explains the high number (37%) of obstetrician operations (such as Kristeller). The data relative to the newborn (22 male, 40 female) indicates a good state of well-being because Apgar and pH indexes are superior to 7 at first and fifth minutes. Concerning the prenatal phase, correlation analysis showed that: the prenatal attachment scores positively correlated with the expected social support and negatively correlated with the “externally oriented thinking” dimension of alexithymia; the maternity social support negatively correlated with total alexithymia score, particularly with the “externally oriented thinking” dimension, and negatively correlated with maternal control of parental bonding. Concerning the delivery data, there are many correlations (after all obvious) among themselves. The most important are that the labour duration negatively correlated with the newborn’s index state of well-being. Finally, concerning the data from the postpartum phase the women’ assessments relative to the partum negatively correlated with the duration of the delivery and positively correlated with the assessment relative to the return to home and the interaction with the newborn. Moreover the length of permanence in the hospital negatively correlated with women’s assessments relative to the return to home that, in turn, positively correlated with the quality of breastfeeding, the interaction between the mother and the newborn and the biological regulation of the child. Finally, the women’ assessments relative to breastfeeding positively correlated with the mother-child interactions and the biological rhythms of children. From the correlation analysis between the variables of the prenatal phase and the data relative to the delivery, emerged that the prenatal attachment scores positively correlated with the dilatation stage scores and with the newborn’s Apgar index at first minute, the paternal care dimension of parental bonding positively correlated with the lengths of the various periods of childbirth like so the paternal control dimension with placental stage. Moreover, emerged that the expected social support positively correlated with the lengths of the various periods of childbirth and that the global alexithymia scores, particularly “difficulty to describe emotions” dimension, negatively correlated with total childbirth scores. From the correlation analysis between the variables of the prenatal phase and variable of the postpartum phase emerged that the total alexithymia scores positively correlated with the time elapsed from the childbirth to the breastfeeding of the child, the difficulty to describe emotions dimension of the alexithymia negatively correlated with the quality of the breastfeeding, the “externally oriented thinking” dimension of the alexithymia negatively correlated with mother-child interactions, and finally the paternal control dimension of the parental bonding negatively correlated with the time elapsed from the child to the breastfeeding of the child. Finally, from the analysis of the correlation between the data of the partum and the women’s assessments of the postpartum phase, emerged the negative correlation between the woman’s assessment relative to the delivery and the quantitative of obstetrician operations and the lengths of the various periods of childbirth, the positive correlation between the women’s assessment about the length of delivery periods and the real lengths of the same ones, the positive relation between woman’s assessment relative to the delivery and the Apgar index of children. In conclusion, there is a remarkable relation between the quality of the relationship the woman establishes with the foetus that influences the course of the pregnancy and the delivery that, in turn, influences the postpartum outcome, particularly relative to the mother-children relationship. Such data should be confirmed by heterogeneous populations in order to identify vulnerable women and to project focused intervention.

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Fifty-two cases of monomorphic post-transplant lymphoproliferative disorders (M-PTLD), developed in patients undergone solid organ or bone marrow transplantation, were studied by the application of the tissue micro-array (TMA) technology. They included 50 cases of diffuse large B-cell lymphomas (DLBCL) and 2 Burkitt lymphomas (BL). In order to evaluate the immune-profile a large panel of antibodies was applied including several new markers (Cyclin D2, Cyclin D3, p27, PKC-β, FOXP-1 and Survivin) identified as negative prognostic factors in DLBCL of the immunocompetent patient. Out of 50 DLBCL, 23 cases (46%) had an Activated B Cell (ABC) phenotype, 8 (16%) a Germinal Centre B-cell (GCB) phenotype, and 11 (22%) an Unclassified (UC) phenotype. In 8 cases (16%) the subtype was not demonstrable due to sub-optimal preservation or loss of the tissue core. FISH analysis detected BCL2 gene amplification and MYC rearrangement. EBV was identified in 32 cases (64%) performing immunohistochemistry (LMP-1) and in situ hybridization (EBER). Clinical data and follow-up were available in all cases of malignant lymphomas but one. Thirty-two patients died for progression of disease or complications related to transplant (bleeding, bacterial infections, and multi-organ failure); 17 patients are actually alive and disease-free. M-PTLD are aggressive lymphomas characterized by very poor outcome. The neoplastic process is stimulated by a prolonged immunosuppressive status which is capable to induce alterations of the immune system and allow EBV reactivation in previously infected patients. Indeed EBV infection seems to be the most significant risk factor to predict the development of a PTLD while age, sex, site of involvement and type of transplant do not have significant correlation. Furthermore DLBCL arisen in a setting of immunodeficiency share phenotypic and molecular features with DLBCL of the immunocompetent patient. In particular, the former shows a high incidence of BCL2 gene amplification and this aberration typically correlates with “non-GCB” phenotype. Also M-PTLD do express prognostic markers (PKC-β, cyclin D2, FOXP-1, and Survivin): notably, in our study, PKC-β and FOXP-1 were frequently expressed and they were predictive of a shorter overall survival even in lymphomas recognized to have a good prognosis (GCB-type). Given the fact that such molecules are detectable at the time of the diagnosis, we postulate whether a “tailored” or more specific therapy might be applied in the management of the immune-compromised patient.

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Recent reports showed that early-interim PET-scan is the only tool predicting treatment outcome in advanced-stage classical Hodgkin lymphoma (asCHL). We evaluated the prognostic impact of a series of immunohistochemical markers, mentioned in literature as prognostic factors, on tissue microarrays assembled from biopsies of 220 patients: STAT1, SAP, TOP2A, PCNA and CD20, both in neoplastic (HRSC) and microenvironment cells (MC); RRM2, MAD2, CDC2, BCL2, P53, BCL11A and EBER in HRSC; ALDH1A1, TIA-1, granzyme B, perforin, FOXP3, and PD-1 in MC. All patients had been treated with standard ABVD ± Rx therapy. Interim-PET after 2 ABVD courses was evaluated according to the criteria indicated by Gallamini in his study (Journal of Clinical Oncology, 2007). The survival analysis has been performed in a subset of 138 patients whose complete clinical information were available: the mean age was 33.3 years (14-79), the stage III-IVB in 98 and IIB in 40, and the mean follow-up 38.1 months (7.6-71.9). Histopathology review showed: NS-I 75, NS-II 22, MC 20, DL 3, and CHL/nos 18 cases. Interim-PET was positive in 30 patients, while treatment failure was recorded in 32. In univariate analysis the factors related to treatment outcome were BCL2 on HRSC (cut-off value 50%), STAT1/SAP on MC, and PET (Log-rank 6.9, 7.9 and 93.9 respectively). The combined expression of STAT1 and SAP was scored in three levels depending on the architectural pattern: score 0 for expression of both with a diffuse/rosetting pattern; score 1 for discordant combination of diffuse/rosetting and scattered patterns; score 2 for both markers with a scattered pattern; the 3y-PFS were 87.4%, 69.9% and 61.9% respectively. In multivariate analysis PET, BCL2 and STAT1/SAP remained significant (HR: 24.8, 4.6, 7.5 and 5.6, respectively; p<.01). The proposed model is able to predict treatment response in AsCHL, even if with a lower efficacy than PET. However, unlike PET, it can be applied upfront therapy.

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Nach Homogenisation ejakulierter Eberspermien und Zentrifugation des Homogenates blieben mehr als 60% der Aktivität des glykolytischen Enzyms Pyruvatkinase (PK) an Zellfragmenten im Sediment gebunden. Diese strukturgebundene PK wurde als PK-S bezeichnet. Das Detergenz Triton X-100 führte nicht zur Ablösung der PK-S; mit Trypsin konnten jedoch rund 80% der PK-S ohne Verlust an Aktivität von den Strukturen gelöst und durch kombinierte Kationenaustausch- und Hydrophobizitätschromatographie gereinigt werden (spezifische Aktivität: 116,7 U/mg Protein). Die lösliche PK aus Eberspermien konnte ebenfalls durch ein ähnliches Verfahren angereichert werden. Im Gel (SDS-PAGE) zeigten die Untereinheiten der PK-S mit 64.400 eine geringfügig größere relative Molekülmasse als die der PK-M1 aus Kaninchenmuskel (62.000). Die kinetischen Eigenschaften der abgelösten PK-S als auch der noch an Spermienstrukturen gebundenen PK-S und der löslichen PK aus Eberspermien waren sehr ähnlich und entsprachen der M1-Isoform der PK. Antikörper gegen Kaninchenmuskel-PK (Anti-PK-M1) reagierten auch mit der löslichen PK und der PK-S aus Eberspermien. Edman-Abbau der ersten 19 Aminosäuren zeigte, dass die tryptisch abgelöste PK-S am N-Terminus um 5 Aminosäuren gegenüber nativer PK-M1 verlängert ist, während der C-Terminus der erhaltenen PK-S-Sequenz mit einem meist nahe dem N-Terminus gelegenen Sequenzabschnitt der PK-M1 und -M2 übereinstimmt. Die N-terminale Verlängerung der nativen PK-S enthält sicherlich mehr als die nach tryptischer Lyse nachgewiesenen 5 Aminosäuren. Vergleiche der Aminosäure- und übersetzten Nukleotidsequenzen sowie die kinetischen Eigenschaften lassen vermuten, dass die PK-S, wie die PK-M1 und PK-M2, vom PKM-Gen codiert wird. Gegen die gereinigte PK-S wurden Antikörper in Kaninchen produziert. Da das Antiserum nicht ausreichend spezifisch für PK-S war, wurden aus ihm affinitätschromatographisch Antikörper (Anti-PK-S) isoliert, die hohe Affinität zu einem synthetisierten PK-S-Peptid (13 N-terminale Aminosäuren der tryptisch abgelösten PK-S) hatten. Dieses Anti-PK-S-Präparat war spezifisch für PK-S; es reagierte weder mit Kaninchenmuskel-PK noch mit löslicher PK oder anderen Proteinen aus Eberspermien. Anti-PK-S und Anti-PK-M1 wurden zur Lokalisierung von PK-S und löslicher PK in Spermien von Eber, Bulle und Mensch sowie in Schnitten von Eberhoden eingesetzt. Mit Anti-PK-S wurden der Bereich des Akrosoms und das lange flagellare Hauptstück sowie der Übergangsbereich zwischen Kopf und Mittelstück von Eberspermien fluoreszenzmarkiert, wogegen das kurze, die Mitochondrien enthaltende Mittelstück des Flagellums und der postakrosomale Kopfbereich nur mit Anti-PK-M1 markiert wurden. Immunogoldmarkierung in elektronenmikroskopischen Bildern bestätigte die Lokalisierung von PK-S im Akrosombereich. Im Hauptstück banden Anti-PK-M1 und Anti-PK-S an die fibröse Scheide. Glyzerinaldehyd-3-phosphat Dehydrogenase (GAPDH) konnte von mir ebenfalls im Akrosombereich, im Übergangsbereich zwischen Kopf und Mittelstück und an der fibrösen Scheide detektiert werden. Auch an Bullen- und Humanspermien konnte über Immunogoldmarkierung PK und vermutlich GAPDH an der fibrösen Scheide gezeigt werden. Im Akrosombereich dieser Spermien waren die Nachweise von PK und GAPDH jedoch nicht sicher. In Eberhodenschnitten war die PK-S erstmals, oder zumindest vermehrt, in den elongierenden Spermatiden über Fluoreszenzmarkierung nachweisbar, während andere, vermutlich somatische PK vermehrt in den früheren Stadien (Spermatogonien, aber auch in den Spermatozyten und runden Spermatiden) auftrat. Für die GAPDH zeigte sich ein ähnlicher Entwicklungsverlauf. Die Ergebnisse zeigen, dass in Eberspermien zwei Isoformen der PK auftreten: eine N-terminal verlängerte, strukturgebundene Form, die PK-S, und eine lösliche Form, die beide der PK-M1 ähneln. Der ungewöhnliche N-Terminus der PK-S dient vermutlich der spezifischen räumlichen Anordnung der PK-S im Akrosombereich und an der fibrösen Scheide, nicht aber der Modulation kinetischer Eigenschaften. Meine Untersuchungen stützen die Hypothese, dass in bestimmten Kompartimenten von Säugerspermien die Glykolyse durch Verankerung einiger ihrer Enzyme strukturell hochgeordnet ist. Dadurch wird vermutlich die Versorgung der Mitochondrien-freien Regionen mit ATP sichergestellt. Man kann diese Organisation als Anpassung des Stoffwechsels von Spermien deuten, bei denen die Mitochondrien in einem kleinen Bereich (Mittelstück) hinter dem Spermienkopf kompartimentiert sind. Im Hauptstück des Flagellums könnte die Glykolyse ATP für die Spermienmotilität liefern, im Akrosombereich für die Verhinderung einer vorzeitigen Akrosomreaktion. Somit käme der strukturierten Glykolyse eine essentielle Bedeutung für die Befruchtungsfähigkeit von Säugerspermien zu.