bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inducible site‐specific recombination in myelinating cells
Authors: Doerflinger Nathalie H. , Macklin Wendy B. , Popko Brian 
Published: December 2002

AbstractSummary: To explore the function of genes expressed by myelinating cells we have developed a model system that allows for the inducible ablation of predetermined genes in oligodendrocytes and Schwann cells. The Cre/loxP recombination system provides the opportunity to generate tissue‐specific somatic mutations in mice. We have used a fusion protein between the Cre recombinase and a mutated ligand‐binding domain of the human estrogen receptor (CreERT) to obtain inducible, site‐specific recombination. CreERT expression was placed under the transcriptional control of the regulatory sequences of the myelin proteolipid protein (PLP) gene, which is abundantly expressed in oligodendrocytes and to a lesser extent in Schwann cells. The CreERT fusion protein translocated to the nucleus and mediated the recombination of a LacZ reporter transgene in myelinating cells of PLP/CreERT mice injected with the synthetic steroid tamoxifen. In untreated animals CreERT remained cytoplasmic, and there was no evidence of recombination. The PLP/ CreERT animals should be very useful in elucidating and distinguishing a particular gene's function in the formation and maintenance of the myelin sheath and in analyzing mature oligodendrocyte function in pathological conditions. genesis 35:63–72, 2003. © 2002 Wiley‐Liss, Inc.
Cre‐loxp fate‐mapping of Pax6 enhancer active retinal and pancreatic progenitors
Authors: Zhang Xin , Heaney Shaun , Maas Richard L. 
Published: December 2002

AbstractSummary: Pax6 plays important roles in the control of ocular and pancreatic development. We identified a 450 bp Pax6 enhancer that contains two interacting sequences: a 274 bp fragment sufficient for expression in retinal progenitors and an adjacent 156 bp fragment required for expression in pancreatic progenitors. Since this enhancer is only transiently expressed during embryogenesis, a Cre‐loxP fate‐mapping strategy was used to investigate the developmental potential of these progenitors. Surprisingly, the labeled retinal precursors predominantly gave rise to horizontal cells, indicating a cell lineage role in horizontal cell differentiation. In the pancreas, all enhancer‐specific cells were restricted to endocrine and ductal cell lineages. This result lends support to a model whereby Pax6‐expressing progenitors contribute to the adult pancreatic islets and ducts. The progenitor cell‐specificity of this enhancer will be useful in studies that require either cell‐specific expression or conditional gene inactivation in these cell populations. genesis 35:22–30, 2003. © 2002 Wiley‐Liss, Inc.
The proto‐oncogene BCL‐6 in normal and malignant B cell development
Authors: Niu Huifeng 
Published: December 2002

AbstractBCL‐6 is an important regulator of the immune system. It is required for GC formation and T cell dependent antibody responses. Mice deficient in BCL‐6 fail to form GC and mount reduced levels of T cell‐dependent antibody responses. BCL‐6 (−/−) mice, in addition, develop a massive inflammatory response in many organs characterized by eosinophilic infiltration and hyper‐IgE production, a typical Th2 hyperimmune response. This suggests a negative role of BCL‐6 in Th2 pathway. The BCL‐6 gene encodes a POZ/zinc finger transcription repressor highly expressed in GC B cells, but not in pre‐GC B cells or in more differentiated memory or plasma cells. By functioning as a potent transcriptional repressor of various target genes, BCL‐6 modulates IL‐4, BCR, and CD40L signals for normal B cell development. In B cell lymphomas, structural alterations of the BCL‐6 promoter region, including chromosome translocation and somatic hypermutation, represent the most frequent genetic lesions associated with non‐Hodgkin lymphoma, especially of diffuse large cell lymphoma, a malignancy often derived from germinal centre (GC) B cells. This suggests that deregulated expression of BCL‐6 may contribute to lymphomagenesis. Copyright © 2002 John Wiley & Sons, Ltd.
Hypermethylation of gene promoters in hematological neoplasia
Authors: Chim C. S. , Liang R. , Kwong Y. L. 
Published: December 2002

AbstractCancer cells are associated with global hypomethylation but with focal hypermethylation of specific gene promoters organized as CpG island. DNA methyltransferases, DNMT1 and 3 (3a and 3b), have been implicated in mediating maintenance and de novo methylation. Hypermethylation of gene promoters results in the inactivation of the corresponding genes, by preclusion of the formation of the transcription complex, due to the recruitment of MBP, MeCPs and histone deacetylase. This results in the deacetylation of histone and thus a compact chromatin complex unfavourable for the initiation of transcription. This methylation‐associated gene silencing has been demonstrated in various genes including tumour suppressor genes (p15, p16, p73, VHL). Therefore, gene promoter hypermethylation collaborates with other mechanisms of gene inactivation such as deletion and intragenic mutations to fulfil Knudson's hypothesis. Hypermethylation may serve as a molecular disease marker for the detection of minimal residual disease. Emerging evidence suggests a possible prognostic value of gene promoter hypermethylation. Moreover, gene hypermethylation may also serve as a target for therapeutic invention by hypomethylating agents. Copyright © 2002 John Wiley & Sons, Ltd.
Characteristics and survival of patients with non‐Hodgkin's lymphoma with and without acquired immunodeficiency syndrome
Authors: Diamond Catherine , Taylor Thomas H. , Anton‐Culver Hoda 
Published: December 2002

AbstractOur objective was to determine the characteristics and survival of patients with non‐Hodgkin's lymphoma (NHL) with and without acquired immunodeficiency syndrome (AIDS). A cancer registry and AIDS registry linkage for San Diego County was performed in October 1998 as part of a national multicentre study. We performed Kaplan–Meier analysis to compare survival in NHL patients with and without AIDS, after matching for age, sex, and race/ethnicity. We performed logistic regression to determine which patient and tumour characteristics were significantly associated with 1‐year survival. Of the 4361 cases of NHL, 324 (7%) had AIDS and 4037 (93%) were not known to have AIDS. Patients with AIDS were more likely to have extranodal, high‐grade, and disseminated NHL diagnosed by non‐histologic means and were less likely to have received chemotherapy. Patients with AIDS and NHL who survived at least 1 year had less advanced disease stage and received chemotherapy. The median survival in patients with AIDS was 4 months (95% confidence interval (CI): 4–5) and 95 months (95% CI: 58–157) in patients without AIDS (P<0.001). Although these patients with AIDS‐related NHL were unlikely to survive, the highly active antiretroviral agents currently used may improve outcomes in future patients. Copyright © 2002 John Wiley & Sons, Ltd.
Adding more observations to saturated D‐optimal resolution III two‐level factorial designs
Authors: Hedayat A. S. , Zhu Haiyuan 
Published: December 2002

AbstractWe consider the class of saturated main effect plans for the 2k factorial. With these saturated designs, the overall mean and all main effects can be unbiasedly estimated provided that there are no interactions. However, there is no way to estimate the error variance with such designs. Because of this and other reasons, we like to add some additional runs to the set of (k+1) runs in the D‐optimal design in this class. Our goals here are: (1) to search for s additional runs so that the resulting design based on (k+s+1) runs yields a D‐optimal design in the class of augmented designs; (2) to classify all the runs into equivalent classes so that the runs in the same equivalent class give us the same value of the determinant of the information matrix. This allows us to trade runs for runs if this becomes necessary; (3) to obtain upper bounds for determinant of the information matrices of augmented designs. In this article we shall address these approaches and present some new results. © 2002 Wiley Periodicals, Inc. J Combin Designs 11: 51–77, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jcd.10026
New type of block design
Authors: Mendelsohn N. S. , Liang M. 
Published: December 2002

AbstractWe are already familiar with (υ, k, λ)‐difference sets and (υ, k, λ)‐designs. In this paper, we will introduce a new class of difference sets and designs: (υ, k, [λ1, λ2, … , λm])‐difference sets and (υ, k, [λ1,λ2, … , λm])‐designs. We will mainly study designs with a relationship we call λ‐equivalence and use them to produce other designs. Some existence or nonexistence theorems will be given. © 2002 Wiley Periodicals, Inc. J Combin Designs 11: 1–23, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jcd.10031
Further results on large sets of disjoint group‐divisible designs with block size three and type 2n41
Authors: Cao H. , Lei J. , Zhu L. 
Published: December 2002

AbstractLarge sets of disjoint group‐divisible designs with block size three and type 2n41 were first studied by Schellenberg and Stinson because of their connection with perfect threshold schemes. It is known that such large sets can exist only for n ≡0 (mod 3) and do exist for all odd n ≡ (mod 3) and for even n=24m, where m odd ≥ 1. In this paper, we show that such large sets exist also for n=2k(3m), where m odd≥ 1 and k≥ 5. To accomplish this, we present two quadrupling constructions and two tripling constructions for a special large set called *LS(2n). © 2002 Wiley Periodicals, Inc. J Combin Designs 11: 24–35, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jcd.10032
Slope packings and coverings, and generic algorithms for the discrete logarithm problem
Authors: Chateauneuf M. , Ling A. C. H. , Stinson D. R. 
Published: December 2002

AbstractWe consider the set of slopes of lines formed by joining all pairs of points in some subset S of a Desarguesian affine plane of prime order p. If all the slopes are distinct and non‐infinite, we have a slope packing; if every possible non‐infinite slope occurs, then we have a slope covering. We review and unify some results on these problems that can be derived from the study of Sidon sets and sum covers. Then we report some computational results, we have obtained for small values of p. Finally, we point out some connections between slope packings and coverings and generic algorithms for the discrete logarithm problem in prime order (sub)groups. Our results provide a combinatorial characterization of such algorithms, in the sense that any generic algorithm implies the existence of a certain slope packing or covering, and conversely. © 2002 Wiley Periodicals, Inc. J Combin Designs 11: 36–50, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jcd.10033
Supraspinal connections of the ovary: Structural and functional aspects
Authors: Gerendai Ida , Kocsis Katalin , Halász Béla 
Published: December 2002

AbstractThis review summarizes our recent studies using the viral transneuronal tracing technique to identify sites in the central nervous system (CNS) that are connected with the ovary. A neurotropic virus (pseudorabies virus) was injected into the ovary and various times after the inoculation the spinal cord and brain were examined for virus‐infected neurons identified by immunocytochemistry. Such neurons could be detected in well‐defined cell groups of the spinal cord (intermediolateral cell column), brain stem (vagal nuclei, area postrema, parapyramidal nucleus, caudal raphe nuclei, A1, A5, A7 noradrenergic cell groups, locus coeruleus, Barrington's nucleus, periaqueductal gray), hypothalamus (paraventricular nucleus, anterior hypothalamus, arcuate nucleus, zona incerta), and, at longer survival time, in some telencephalic structures (amygdala, bed nucleus of the stria terminalis). These findings provided the first neuromorphological evidence for the existence of a multisynaptic neuronal pathway between the brain and the ovary presumably involved in the neuronal control of the organ. The observations indicate that there is a significant overlap of CNS structures connected with the ovary, the testis, other organs and organ systems, suggesting similar neuronal circuitries of the autonomic nervous system innervating the different organs. The known descending neuronal connections between the CNS structures labeled from the ovary by the viral transneuronal tracing technique and the findings suggesting a pituitary independent interplay between certain cerebral structures such as the hypothalamus, the amygdala, and the ovary are also summarized in this review. Microsc. Res. Tech. 59:474–483, 2002. © 2002 Wiley‐Liss, Inc.
Localization of calretinin in the rat ovary and in relation to nerve cell bodies in dorsal root and paravertebral ganglia projecting to the ovary
Authors: Burden Hubert W. , Zary Joan T. 
Published: December 2002

AbstractRetrograde tracing with True Blue was combined with immunocytochemistry to determine the source of any calretinin‐immunoreactive (CR‐ir) nerves projecting to the rat ovary. In the ovary, a strong signal for calretinin immunoreactivity was localized in interstitial gland cells; however, no intraovarian CR‐ir nerves could be demonstrated. When the superior ovarian nerve was isolated, cut, and True Blue applied to the proximal end, the fluorescent dye was retrogradely transported to a population of cells located in T‐12, T‐13, and L‐1 dorsal root and paravertebral ganglia. There was virtually no dual labeling of cells in these ganglia with calretinin (< 0.009% dual labeling in dorsal root and <0.014% in paravertebral ganglia). However, greater than two‐thirds of the True Blue‐labeled cells were immediately adjacent to CR‐ir cells in dorsal root ganglia. This arrangement is suggestive of a paracrine mechanism between CR‐ir cells and cells projecting to the ovary. In paravertebral ganglia, 63% of cells projecting to the ovary were surrounded completely or partially by beaded CR‐ir nerve fibers. The source of these fibers (sensory or preganglionic sympathetic) is unknown but hypothesized to be preganglionic. Collectively, these observations suggest a participatory role for calretinin in ovarian function, either directly via effects on the interstitial gland or indirectly by influencing neurons projecting to the ovary. Microsc. Res. Tech. 59:490–494, 2002. © 2002 Wiley‐Liss, Inc.
Neurotrophic control of ovarian development
Authors: Dissen Gregory A. , Romero Carmen , Paredes Alfonso , Ojeda Sergio R. 
Published: December 2002

AbstractSubstantial evidence now exists indicating that the neurotrophins, a family of growth factors required for the survival, development, and differentiation of various neuronal populations of the nervous system, are also important for the development of nonneuronal tissues. Such a function was first suggested by studies showing the presence of high‐affinity neurotrophin receptors in a variety of nonneuronal tissues including those of the cardiovascular, endocrine, immune, and reproductive systems. Within the latter, the gonads appear to be a preferential site of neurotrophin action as suggested by the presence in the mammalian ovary of at least four of the five known neurotrophins and all of the neurotrophin receptors thus far identified. While the various functions that the neurotrophins may have in the ovary are still being elucidated, it is now clear that in addition to recruiting the ovarian innervation, they play a direct role in the regulation of two different maturational periods that are critical for the acquisition of female reproductive function: early follicular development and ovulation. Neurotrophins facilitate the development of newly formed follicles by promoting the initial differentiation and the subsequent growth of primordial follicles. These actions appear to be related to the ability of neurotrophins to sustain the proliferation of both mesenchymal and granulosa cells, and to induce the synthesis of follicle stimulating hormone (FSH) receptors. At the time of the first ovulation, neurotrophins contribute to the ovulatory cascade by increasing prostaglandin E2 release, reducing gap junction communication, and inducing cell proliferation within the thecal compartment of preovulatory follicles. Microsc. Res. Tech. 59:509–515, 2002. © 2002 Wiley‐Liss, Inc.
Ovarian acetylcholine and muscarinic receptors: Hints of a novel intrinsic ovarian regulatory system
Authors: Mayerhofer Artur , Fritz Stephanie 
Published: December 2002

AbstractMore than two decades ago, the degrading enzyme of the neurotransmitter acetylcholine (ACH) was reported in nerve fibers of the rat ovary. Subsequently, it was assumed that ACH is a neurotransmitter of ovarian nerves, although the sole presence of the degrading enzyme, ACH‐esterase, does not allow such a conclusion. That ACH may be involved in the complex regulation of ovarian functions, including hormone production, was indicated by studies using, for example, granulosa cells (GCs). The lack of detailed information about both source(s) and functions of ACH in the ovary prompted us to examine sites of ovarian ACH‐synthesis and ACH‐receptor‐bearing target cells. We also started to identify functions of ACH in cultured human GCs. While ovarian innervation and recently described neuron‐like cells of the ovary were not immunoreactive for the ACH‐synthesizing enzyme, choline‐acetyl transferase (CHAT), we found immunoreactivity in GCs of rodents and primates. Isolated human and rat GCs produced ACH and contained the vesicular ACH transporter (VACHT). These results indicate that endocrine GCs are an unexpected non‐neuronal source of ACH in the ovary. Moreover, these cells and GCs in vivo contain ACH‐receptors of the muscarinic subtype (MR), namely M1R and M5R. In contrast, oocytes express M3R. MR of human GCs are functional and cholinergic stimulation is linked to rapid increases in intracellular Ca++ levels. M1/5R activation also led to increased cell proliferation of human GCs in vitro and this stimulatory effect was found to be associated with rapid disruption of gap junction communication. Ongoing studies begin to identify regulation of ion channels and altered gene expression as consequences of MR stimulation. Thus, our results outline first details of an unexpected intraovarian, non‐neuronal cholinergic system, and suggest that it may be involved in the regulation of cell proliferation in the ovary. Microsc. Res. Tech. 59:503–508, 2002. © 2002 Wiley‐Liss, Inc.
Changes in sympathetic nerve activity of the mammalian ovary during a normal estrous cycle and in polycystic ovary syndrome: Studies on norepinephrine release
Authors: Lara H.E. , Dorfman M. , Venegas M. , Luza S.M. , Luna S.L. , Mayerhofer A. , Guimaraes M.A. , Rosa E Silva A.A.M. , Ramírez V.D. 
Published: December 2002

AbstractAlthough it has been known for many years that the ovary is innervated by catecholaminergic nerve fibers and much experimental evidence has strengthened the notion that catecholamines are physiologically involved in the control of ovarian function, scarce evidence has been presented as to the role of sympathetic activity in ovarian pathologies that affect reproductive function. The purpose of this article is to provide a succinct overview of the findings in this area and discuss them relative to the pathology of polycystic ovary syndrome, the most common ovarian pathology in women during their reproductive years. Microsc. Res. Tech. 59:495–502, 2002. © 2002 Wiley‐Liss, Inc.
Preovulatory rise of NGF in ovine follicular fluid: Possible involvement in the control of oocyte maturation
Authors: Barboni Barbara , Mattioli Mauro , Gioia Luisa , Turriani Maura , Capacchietti Giulia , Berardinelli Paolo , Bernabò Nicola 
Published: December 2002

AbstractSince nerve growth factor (NGF) is produced in vitro by granulosa cells after gonadotropin stimulation, the present research has been designed to investigate whether this neurotropin is involved in the events triggered by the gonadotropin surge that lead the follicle to ovulate a mature oocyte. To this aim, NGF levels in follicular fluid, collected before or 20 hours after the gonadotropin surge, was measured by ELISA. To evaluate whether NGF may have a non‐neurotropic effect on follicle cells, the presence of NGF receptors was investigated by immunohistochemistry and further evaluated by analysing the tyrosine‐phosphorylation pattern after NGF stimulation in vitro. The effect of NGF on the degree of cumulus expansion, cumulus‐oocyte metabolic coupling, and meiotic maturation was finally studied by using the culture of follicle‐enclosed oocyte. The results demonstrate that GnRH causes a dramatic rise of NGF in large follicles. Immunohistochemistry revealed a discrete positivity for trkA receptors localised in cumulus cells. Tyrosine phosphorylation pattern confirms that somatic cells are capable to transduce NGF signal. By contrast, all the oocytes examined were negative for trkA and did not change the phosphorylation pattern after NGF. In vitro NGF (100 ng/ml) induced a marked cumulus expansion and a progressive cumulus‐oocyte uncoupling similar to that produced by gonadotropins. The addition of NGF also caused the resumption of meiosis in more than 70% of the oocytes analysed with an effect that is only slightly less pronounced than that of gonadotropins (80%). The increase in NGF secretion following gonadotropin surge suggests that this neurotropin may be involved in the control of oocyte maturation. Microsc. Res. Tech. 59:516–521, 2002. © 2002 Wiley‐Liss, Inc.
Intrinsic neurons in the mammalian ovary
Authors: D'Albora Hortensia , Anesetti Gabriel , Lombide Paula , Dees W. Les , Ojeda Sergio R. 
Published: December 2002

AbstractMammalian ovarian function is under endocrine and neural control. Although the extrinsic innervation of the ovary has been implicated in the control of both ovarian development and mature function, it is now clear that, from rats to humans, the ovary is endowed with a network of intrinsic neurons displaying diverse chemical phenotypes. This article describes the presence of these intrinsic neurons in the ovary of different mammalian species, and discusses the possible functions that they may have in the regulation of ovarian physiology. Microsc. Res. Tech. 59:484–489, 2002. © 2002 Wiley‐Liss, Inc.
Role of the central and peripheral nervous system in the ovarian function
Authors: Aguado Luis I. 
Published: December 2002

AbstractThis review attempts to give a comprehensive overview of ovarian innervation, considering the whole nervous system and its different levels that may modify the ovarian function. The connection between the ovary and the central nervous system through the autonomic pathways, including the peripheral ganglia, is highlighted. The evidence obtained over the last years highlights the role of the superior ovarian nerve (SON) in the ovarian phenomena. Besides, the effect on the ovary of conventional neurotransmitters and others such as indolamines and peptides, which have been found in this organ, are discussed. Various reproductive diseases have been studied almost exclusively from the endocrine point of view. It is evident that a better knowledge about the role of the neural factors involved in the ovarian physiology may facilitate the understanding of some of these. A review of the concepts and an update of some experimental designs is made that permits clarifying several aspects of the relationship between the neural system and the ovary. At present, there is no doubt that the innervation of the ovary is involved in several physiological aspects of this gland function. However, the relationship of some levels of the nervous system and the ovary offer a wide avenue for future research. Microsc. Res. Tech. 59:462–473, 2002. © 2002 Wiley‐Liss, Inc.