bluuebunny/crossref_metadata_2025 huggingface dataset:
Endothelial intercellular adhesion molecule (ICAM)–2 regulates angiogenesis
Authors: Huang Miao-Tzu , Mason Justin C. , Birdsey Graeme M. , Amsellem Valerie , Gerwin Nicole , Haskard Dorian O. , Ridley Anne J. , Randi Anna M.
Published: May 2005

Endothelial junctions maintain endothelial integrity and vascular homeostasis. They modulate cell trafficking into tissues, mediate cell-cell contact and regulate endothelial survival and apoptosis. Junctional adhesion molecules such as vascular endothelial (VE)–cadherin and CD31/platelet endothelial cell adhesion molecule (PECAM) mediate contact between adjacent endothelial cells and regulate leukocyte transmigration and angiogenesis. The leukocyte adhesion molecule intercellular adhesion molecule 2 (ICAM-2) is expressed at the endothelial junctions. In this study we demonstrate that endothelial ICAM-2 also mediates angiogenesis. Using ICAM-2–deficient mice and ICAM-2–deficient endothelial cells, we show that the lack of ICAM-2 expression results in impaired angiogenesis both in vitro and in vivo. We show that ICAM-2 supports homophilic interaction, and that this may be involved in tube formation. ICAM-2–deficient cells show defective in vitro migration, as well as increased apoptosis in response to serum deprivation, anti-Fas antibody, or staurosporine. ICAM-2 signaling in human umbilical vein endothelial cells (HUVECs) was found to activate the small guanosine triphosphatase (GTPase) Rac, which is required for endothelial tube formation and migration. These data indicate that ICAM-2 may regulate angiogenesis via several mechanisms including survival, cell migration, and Rac activation. Our findings identify a novel pathway regulating angiogenesis through ICAM-2 and a novel mechanism for Rac activation during angiogenesis.
Inhibition of EBF function by active Notch signaling reveals a novel regulatory pathway in early B-cell development
Authors: Smith Emma M. K. , Åkerblad Peter , Kadesch Tom , Axelson Håkan , Sigvardsson Mikael
Published: May 2005

The Notch signaling pathway is involved in several lineage commitment and differentiation events. One of these is fate determination of the common lymphoid progenitor, promoting T-cell development at the expense of B-cell differentiation. It has been suggested that this process relies on Notch's ability to inhibit E proteins, which are crucial for early B-cell development. Here, we report that Notch signaling also modulates the function of the transcription factor, early B-cell factor (EBF). Transient transfection of intracellular Notch1 (Notch1-IC) into a pre-B cell line resulted in the down-regulation of EBF-regulated promoters and diminished the capacity of EBF to activate these promoters in an epithelial cell line. This correlated with a reduction in the ability of EBF to bind DNA. Ligand-induced stimulation of endogenous Notch receptors with Delta4 mimicked the activity of Notch1-IC toward EBF. These data suggest that Notch signaling may affect B-versus T-lineage commitment by the targeting of both EBF and E2A.
Idiopathic portal hypertension complicating systemic sclerosis: a case report
Authors: Moschos John , Leontiadis Grigoris I , Kelly Clive , Henry James , Kadis Savvas
Published: May 2005

Background

Patients with systemic sclerosis may develop mild abnormalities of liver function tests. More serious hepatic involvement has been well documented but is rare. Idiopathic portal hypertension had been reported only in a few female patients with systemic sclerosis.

Case presentation

An 82-year-old man with known systemic sclerosis presented with melaena. Urgent gastroscopy revealed oesophageal varices, which re-started bleeding during the procedure and were treated ensocopically, with Sengstaken tube and glypressin. Liver function tests and coagulation were normal. Non-invasive liver screen (including hepatitis viral serology and autoantibodies) was negative. Ultrasound scan of the abdomen revealed a small liver with coarse texture and no focal lesion. Hepato-portal flow was demonstrated in the portal vein. The spleen was enlarged. A moderate amount of free peritoneal fluid was present. A CT scan confirmed the absence of portal vein thrombosis. One month following discharge the patient had a liver biopsy. Histological examination showed essentially normal liver tissue; there was no evidence of any excess inflammation and no features to suggest cirrhosis or drug-induced liver disease. Taking into account the above evaluation we concluded that the patient had idiopathic portal hypertension.

Conclusion

Both male and female patients with systemic sclerosis may – rarely – develop idiopathic portal hypertension.
Salivary antibodies induced by the seven-valent PncOMPC conjugate vaccine in the Finnish Otitis Media Vaccine Trial
Authors: Nurkka Anu , Lahdenkari Mika , Palmu Arto AI , Käyhty Helena ,   the FinOM Study Group
Published: May 2005

Background

Mucosal antibodies have been suggested to have a role in defence against pneumococcal infections. We investigated here the ability of a seven-valent pneumococcal conjugate vaccine, PncOMPC, to induce mucosal immune response.

Methods

Healthy Finnish children (n = 111), a subcohort of the Finnish Otitis Media Vaccine Trial, were recruited and 56 of them were immunised with the PncOMPC at the age of 2, 4, and 6 months. At 12 months of age, 49 of them received the PncOMPC and 7 were vaccinated with the pneumococcal polysaccharide vaccine (PncPS) as a booster. The control group of 55 children received a hepatitis B vaccine at the same ages. Salivary anti-Pnc IgG, IgA, IgA1, and IgA2 antibodies to serotypes 6B, 14, 19F, and 23F were measured in both groups at the age of 7 and 13 months.

Results

Salivary anti-Pnc IgG and IgA were detected more often in the PncOMPC than in the control group. However, the difference between groups was significant only for 19F and 23F IgA concentrations at the age of 7 months. At the age of 13 months, antibody concentrations did not differ between PncOMPC and control groups. The rises in IgA concentrations between 7 and 13 months of age were mainly of subclass IgA1. Further, there is a clear trend that PncPS booster induces higher salivary anti-Pnc PS antibody concentrations than the PncOMPC.

Conclusion

We found that PncOMPC can induce a mucosal IgA response. However, the actual impact of mucosal antibodies in protection against pneumococcal infections is not clear.
Antipsychotic monotherapy and polypharmacy in the naturalistic treatment of schizophrenia with atypical antipsychotics
Authors: Faries Douglas , Ascher-Svanum Haya , Zhu Baojin , Correll Christoph , Kane John
Published: May 2005

Background

Antipsychotic monotherapy is recognized as the treatment of choice for patients with schizophrenia. Simultaneous treatment with multiple antipsychotics (polypharmacy) is suggested by some expert consensus guidelines as the last resort after exhausting monotherapy alternatives. This study assessed the annual rate and duration of antipsychotic monotherapy and its inverse, antipsychotic polypharmacy, among schizophrenia patients initiated on commonly used atypical antipsychotic medications.

Methods

Data were drawn from a large prospective naturalistic study of patients treated for schizophrenia-spectrum disorders, conducted 7/1997–9/2003. Analyses focused on patients (N = 796) who were initiated during the study on olanzapine (N = 405), quetiapine (N = 115), or risperidone (N = 276). The percentage of patients with monotherapy on the index antipsychotic over the 1-year post initiation, and the cumulative number of days on monotherapy were calculated for all patients and for each of the 3 atypical antipsychotic treatment groups. Analyses employed repeated measures generalized linear models and non-parametric bootstrap re-sampling, controlling for patient characteristics.

Results

During the 1-year period, only a third (35.7%) of the patients were treated predominately with monotherapy (>300 days). Most patients (57.7%) had at least one prolonged period of antipsychotic polypharmacy (>60 consecutive days). Patients averaged 195.5 days on monotherapy, 155.7 days on polypharmacy, and 13.9 days without antipsychotic therapy. Olanzapine-initiated patients were significantly more likely to be on monotherapy with the initiating antipsychotic during the 1-year post initiation compared to risperidone (p = .043) or quetiapine (p = .002). The number of monotherapy days was significantly greater for olanzapine than quetiapine (p < .001), but not for olanzapine versus risperidone, or for risperidone versus quetiapine-initiated patients.

Conclusion

Despite guidelines recommending the use of polypharmacy only as a last resort, the use of antipsychotic polypharmacy for prolonged periods is very common during the treatment of schizophrenia patients in usual care settings. In addition, in this non-randomized naturalistic observational study, the most commonly used atypical antipsychotics significantly differed on the rate and duration of antipsychotic monotherapy. Reasons for and the impact of the predominant use of polypharmacy will require further study.
Pre-competition habits and injuries in Taekwondo athletes
Authors: Kazemi Mohsen , Shearer Heather , Su Choung Young
Published: May 2005

Background

Over the past decade, there has been heightened interest in injury rates sustained by martial arts athletes, and more specifically, Taekwondo athletes. Despite this interest, there is a paucity of research on pre-competition habits and training of these athletes. The purpose of this pilot study was to assess training characteristics, competition preparation habits, and injury profiles of Taekwondo athletes.

Methods

A retrospective survey of Canadian male and female Taekwondo athletes competing in a national tournament was conducted. Competitors at a Canadian national level tournament were given a comprehensive survey prior to competition. Items on training characteristics, diet, and injuries sustained during training and competition were included. Questionnaires were distributed to 60 athletes.

Results

A response rate of 46.7% was achieved. Of those that responded, 54% dieted prior to competition, and 36% dieted and exercised pre-competition. Sixty-four percent of the athletes practised between 4–6 times per week, with 54% practicing 2 hours per session. Lower limb injuries were the most common (46.5%), followed by upper extremity (18%), back (10%), and head (3.6%). The majority of injuries consisted of sprains/strains (45%), followed by contusions, fractures, and concussions. More injuries occurred during training, including 59% of first injuries.

Conclusion

More research needs to be conducted to further illustrate the need for appropriate regulations on weight cycling and injury prevention.
Industrial-scale production and purification of a heterologous protein in Lactococcus lactis using the nisin-controlled gene expression system NICE: The case of lysostaphin
Authors: Mierau Igor , Leij Peter , van Swam Iris , Blommestein Barry , Floris Esther , Mond James , Smid Eddy J
Published: May 2005

Background

The NI sin-C ontrolled gene E xpression system NICE of Lactococcus lactis is one of the most widespread used expression systems of Gram-positive bacteria. It is used in more than 100 laboratories for laboratory-scale gene expression experiments. However, L. lactis is also a micro-organism with a large biotechnological potential. Therefore, the aim of this study was to test whether protein production in L. lactis using the NICE system can also effectively be performed at the industrial-scale of fermentation.

Results

Lysostaphin, an antibacterial protein (mainly against Staphylococcus aureus) from S. simulans biovar. Staphylolyticus, was used as a model system. Food-grade lysostaphin expression constructs in L. lactis were grown at 1L-, 300-L and 3000-L scale and induced with nisin for lysostaphin production. The induction process was equally effective at all scales and yields of about 100 mg/L were obtained. Up-scaling was easy and required no specific effort. Furthermore, we describe a simple and effective way of downstream processing to obtain a highly purified lysostaphin, which has been used for clinical phase I trials.

Conclusion

This is the first example that shows that nisin-regulated gene expression in L. lactis can be used at industrial scale to produce large amounts of a target protein, such as lysostaphin. Downstream processing was simple and in a few steps produced a highly purified and active enzyme.
Stepping stability: effects of sensory perturbation
Authors: McGibbon Chris A , Krebs David E , Wagenaar Robert
Published: May 2005

Background

Few tools exist for quantifying locomotor stability in balance impaired populations. The objective of this study was to develop and evaluate a technique for quantifying stability of stepping in healthy people and people with peripheral (vestibular hypofunction, VH) and central (cerebellar pathology, CB) balance dysfunction by means a sensory (auditory) perturbation test.

Methods

Balance impaired and healthy subjects performed a repeated bench stepping task. The perturbation was applied by suddenly changing the cadence of the metronome (100 beat/min to 80 beat/min) at a predetermined time (but unpredictable by the subject) during the trial. Perturbation response was quantified by computing the Euclidian distance, expressed as a fractional error, between the anterior-posterior center of gravity attractor trajectory before and after the perturbation was applied. The error immediately after the perturbation (Emax), error after recovery (Emin) and the recovery response (Edif) were documented for each participant, and groups were compared with ANOVA.

Results

Both balance impaired groups exhibited significantly higher Emax (p= .019) and Emin (p= .028) fractional errors compared to the healthy (HE) subjects, but there were no significant differences between CB and VH groups. Although response recovery was slower for CB and VH groups compared to the HE group, the difference was not significant (p= .051).

Conclusion

The findings suggest that individuals with balance impairment have reduced ability to stabilize locomotor patterns following perturbation, revealing the fragility of their impairment adaptations and compensations. These data suggest that auditory perturbations applied during a challenging stepping task may be useful for measuring rehabilitation outcomes.
Nonmelanoma Skin Cancer in Survivors of Childhood and Adolescent Cancer: A Report From the Childhood Cancer Survivor Study
Authors: Perkins Joanna L. , Liu Yan , Mitby Pauline A. , Neglia Joseph P. , Hammond Sue , Stovall Marilyn , Meadows Anna T. , Hutchinson Ray , Dreyer ZoAnn E. , Robison Leslie L. , Mertens Ann C.
Published: May 2005

Purpose

Nonmelanoma skin cancer (NMSC) has become the most common type of cancer in many populations throughout the world. Ultraviolet and ionizing radiation are known risk factors. Because NMSCs are rarely lethal and most cancer registries do not routinely report data regarding these cancers, they have received little attention in studies evaluating long-term effects of cancer therapy. This article reports on the occurrence of secondary NMSC as a long-term effect of cancer therapy in survivors of childhood cancer.

Patients and Methods

The Childhood Cancer Survivor Study (CCSS) is a cohort study of 5-year survivors of childhood and adolescent cancer from 25 participating institutions in North America. NMSC patients were defined by a history of basal cell or squamous cell carcinoma of the skin after primary malignancy treatment. Demographic and treatment data were collected and analyzed.

Results

Among the 13,132 eligible CCSS participants, 213 have reported NMSC; 99 patients (46%) have had multiple occurrences. Median age of occurrence was 31 years (range, 7 to 46 years). Location of NMSC included head and neck (43%), back (24%), chest (22%), abdomen and pelvis (5%), extremity (3%), and unknown (4%). Ninety percent of patients had previously received radiation therapy (RT); 90% of tumors occurred within the RT field. RT was associated with a 6.3-fold increase in risk (95% CI, 3.5- to 11.3-fold).

Conclusion

Long-term survivors of childhood and adolescent cancer who were treated with RT are at highest risk for developing NMSC. Educational efforts need to be directed to this population to facilitate early diagnosis of NMSC and reduction in sun exposure.
Analysis of Treatment Practices for Elderly Cancer Patients in Ontario, Canada
Authors: Townsley Carol , Pond Gregory R. , Peloza Brenda , Kok Joanne , Naidoo Kendra , Dale Darlene , Herbert Carole , Holowaty Eric , Straus Sharon , Siu Lillian L.
Published: May 2005

Purpose

Older patients are underrepresented in many areas of cancer services utilization and in clinical trial enrollment. This study evaluates whether age, when adjusted for sex, comorbidity, stage, tumor site, geography, and time period, is predictive of cancer treatment practice.

Methods

First, we used the Ontario Cancer Registry (OCR) to examine for any apparent differences in treatment practices between elderly (≥ 70 years) and younger patients in the last three decades. Second, we performed a chart review of 1,505 patients with lung, breast, and colorectal cancers seen in Ontario either at an urban center, the Princess Margaret Hospital, or at a rural center, the Northwestern Regional Cancer Centre. Patients were randomly selected from two time periods, 1977 to 1978 and 1997; and the study population was to comprise at least 50% elderly patients.

Results

OCR data demonstrated that, in some settings, such as colorectal cancer, the proportions of elderly cancer patients who were referred to cancer centers and who received any cancer treatment were lower than their younger counterparts. The chart review data showed that increasing age was a significant negative predictor for receiving any cancer treatment (P < .001, multivariate analysis) and for having a clinical trial discussion with the treating specialist (P < .001, multivariate analysis).

Conclusion

Independent of other factors, older age is consistently a cause of disparity in cancer treatment practice and in clinical trial discussion with patients. By increasing the accrual rate of elderly cancer patients in clinical trials, a better understanding of appropriate therapies for this patient population can be obtained and may, thereby, impact on their cancer-related morbidity and mortality.
Endogenous Ghrelin Regulates Episodic Growth Hormone (GH) Secretion by Amplifying GH Pulse Amplitude: Evidence from Antagonism of the GH Secretagogue-R1a Receptor
Authors: Zizzari P. , Halem H. , Taylor J. , Dong J. Z. , Datta R. , Culler M. D. , Epelbaum J. , Bluet-Pajot M. T.
Published: May 2005

Ghrelin was purified from rat stomach as an endogenous ligand for the GH secretagogue (GHS) receptor. As a GHS, ghrelin stimulates GH release, but it also has additional activities, including stimulation of appetite and weight gain. Plasma GH and ghrelin secretory patterns appear unrelated, whereas many studies have correlated ghrelin variations with food intake episodes. To evaluate the role of endogenous ghrelin, GH secretion and food intake were monitored in male rats infused sc (6 μg/h during 10 h) or intracerebroventricularly (5 μg/h during 48 h) with BIM-28163, a full competitive antagonist of the GHS-R1a receptor. Subcutaneous BIM-28163 infusion significantly decreased GH area under the curve during a 6-h sampling period by 54% and peak amplitude by 46%. Twelve hours after the end of treatment these parameters returned to normal. Central treatment was similarly effective (−37 and −42% for area under the curve and −44 and −49% for peak amplitude on the first and second days of infusion, respectively). Neither peripheral nor central BIM-28163 injection modified GH peak number, GH nadir, or IGF-I levels. In this protocol, food intake is not strongly modified and water intake is unchanged. Subcutaneous infusion of BIM-28163 did not change plasma leptin and insulin levels evaluated at 1200 and 1600 h. On the contrary, central BIM-28163 infusion slightly increased leptin and significantly increased insulin concentrations. Thus, endogenous ghrelin, through GHS-R1a, acts as a strong endogenous amplifier of spontaneous GH peak amplitude. The mechanisms by which ghrelin modifies food intake remain to be defined and may involve a novel GHS receptor.
Src Homology 3-Domain Growth Factor Receptor-Bound 2-Like (Endophilin) Interacting Protein 1, a Novel Neuronal Protein that Regulates Energy Balance
Authors: Trevaskis James , Walder Ken , Foletta Victoria , Kerr-Bayles Lyndal , McMillan Janine , Cooper Adrian , Lee Scott , Bolton Kristy , Prior Matthew , Fahey Richard , Whitecross Kate , Morton Gregory J. , Schwartz Michael W. , Collier Greg R.
Published: May 2005

To identify genes involved in the central regulation of energy balance, we compared hypothalamic mRNA from lean and obese Psammomys obesus, a polygenic model of obesity, using differential display PCR. One mRNA transcript was observed to be elevated in obese, and obese diabetic, P. obesus compared with lean animals and was subsequently found to be increased 4-fold in the hypothalamus of lethal yellow agouti (Ay/a) mice, a murine model of obesity and diabetes. Intracerebroventricular infusion of antisense oligonucleotide targeted to this transcript selectively suppressed its hypothalamic mRNA levels and resulted in loss of body weight in both P. obesus and Sprague Dawley rats. Reductions in body weight were mediated by profoundly reduced food intake without a concomitant reduction in metabolic rate. Yeast two-hybrid screening, and confirmation in mammalian cells by bioluminescence resonance energy transfer analysis, demonstrated that the protein it encodes interacts with endophilins, mediators of synaptic vesicle recycling and receptor endocytosis in the brain. We therefore named this transcript Src homology 3-domain growth factor receptor-bound 2-like (endophilin) interacting protein 1 (SGIP1). SGIP1 encodes a large proline-rich protein that is expressed predominantly in the brain and is highly conserved between species. Together these data suggest that SGIP1 is an important and novel member of the group of neuronal molecules required for the regulation of energy homeostasis.
Perinatal Exposure to Bisphenol-A Alters Peripubertal Mammary Gland Development in Mice
Authors: Muñoz-de-Toro Monica , Markey Caroline M. , Wadia Perinaaz R. , Luque Enrique H. , Rubin Beverly S. , Sonnenschein Carlos , Soto Ana M.
Published: May 2005

Developmental exposure to estrogenic chemicals induces morphological, functional, and behavioral anomalies associated with reproduction. Humans are exposed to bisphenol-A (BPA), an estrogenic compound that leaches from dental materials and plastic food and beverage containers. The aim of the present study was to determine the effects of perinatal exposure to low, environmentally relevant doses of BPA [25 and 250 ng BPA/kg body weight (bw)·d] on the peripubertal development of the mammary gland. BPA exposure enhanced the mammary glands’ sensitivity to estradiol in ovariectomized CD-1 mice. In their intact 30-d-old littermates, the area and numbers of terminal end buds relative to the gland ductal area increased whereas their apoptotic activity decreased. There was a positive correlation between ductal length and the age at first proestrus; that was reduced as the BPA dose increased, suggesting that BPA exposure slows down ductal invasion of the stroma. There was also a significant increase of progesterone receptor-positive ductal epithelial cells that were localized in clusters, suggesting future branching points. Indeed, lateral branching was significantly enhanced at 4 months of age in mice exposed to 25 ng BPA /kg bw·d. In conclusion, perinatal exposure to environmentally relevant BPA doses results in persistent alterations in mammary gland morphogenesis. Of special concern is the increased terminal end bud density at puberty as well as the increased number of terminal ends reported previously in adult animals, as these two structures are the sites at which cancer arises in humans and rodents.
Regulation of Kiss1 Gene Expression in the Brain of the Female Mouse
Authors: Smith Jeremy T. , Cunningham Matthew J. , Rissman Emilie F. , Clifton Donald K , Steiner Robert A.
Published: May 2005

The Kiss1 gene encodes a family of neuropeptides called kisspeptins, which activate the receptor G protein-coupled receptor-54 and play a role in the neuroendocrine regulation of GnRH secretion. We examined whether estradiol (E2) regulates KiSS-1 in the forebrain of the female mouse by comparing KiSS-1 mRNA expression among groups of ovary-intact (diestrus), ovariectomized (OVX), and OVX plus E2-treated mice. In the arcuate nucleus (Arc), KiSS-1 expression increased after ovariectomy and decreased with E2 treatment. Conversely, in the anteroventral periventricular nucleus (AVPV), KiSS-1 expression was reduced after ovariectomy and increased with E2 treatment. To determine whether the effects of E2 on KiSS-1 are mediated through estrogen receptor (ER)α or ERβ, we evaluated the effects of E2 in OVX mice that lacked functional ERα or ERβ. In OVX mice that lacked functional ERα, KiSS-1 mRNA did not respond to E2 in either the Arc or AVPV, suggesting that ERα is essential for mediating the inhibitory and stimulatory effects of E2. In contrast, KiSS-1 mRNA in OVX mice that lacked functional ERβ responded to E2 exactly as wild-type animals. Double-label in situ hybridization revealed that virtually all KiSS-1-expressing neurons in the Arc and AVPV coexpress ERα, suggesting that the effects of E2 are mediated directly through KiSS-1 neurons. We conclude that KiSS-1 neurons in the Arc, which are inhibited by E2, may play a role in the negative feedback regulation of GnRH secretion, whereas KiSS-1 neurons in the AVPV, which are stimulated by E2, may participate in the positive feedback regulation of GnRH secretion.
Calmodulin-Dependent Kinase IV Stimulates Vitamin D Receptor-Mediated Transcription
Authors: Ellison Tara I. , Dowd Diane R. , MacDonald Paul N.
Published: May 2005

1,25-Dihydroxyvitamin D3 [1,25-(OH)2D3] promotes intestinal absorption of calcium primarily by binding to the vitamin D receptor (VDR) and regulating gene expression. 1,25-(OH)2D3 also exerts rapid actions at the cell membrane that include increasing intracellular calcium levels and activating protein kinase cascades. To explore potential cross talk between calcium signaling elicited by the nongenomic actions of 1,25-(OH)2D3 and the genomic pathway mediated by VDR, we examined the effects of activated Ca2+/calmodulin-dependent kinases (CaMKs) on 1,25-(OH)2D3/VDR-mediated transcription. Expression of a constitutively active form of CaMKIV dramatically stimulated 1,25-(OH)2D3-activated reporter gene expression in COS-7, HeLa, and ROS17/2.8 cell lines. Metabolic labeling studies indicated that CaMKIV increased VDR phosphorylation levels. In addition, CaMKIV increased the independent transcription activity of the VDR coactivator SRC (steroid receptor coactivator) 1, and promoted ligand-dependent interaction between VDR and SRC coactivator proteins in mammalian two-hybrid studies. The functional consequences of this multifaceted mechanism of CaMKIV action were revealed by reporter gene studies, which showed that CaMKIV and select SRC coactivators synergistically enhanced VDR-mediated transcription. These studies support a model in which CaMKIV signaling stimulates VDR-mediated transcription by increasing phosphorylation levels of VDR and enhancing autonomous SRC activity, resulting in higher 1,25-(OH)2D3-dependent interaction between VDR and SRC coactivators.
Modulation of the Expression and Transactivation of Androgen Receptor by the Basic Helix-Loop-Helix Transcription Factor Pod-1 through Recruitment of Histone Deacetylase 1
Authors: Hong Cheol Yi , Gong Eun-Yeung , Kim Kabsun , Suh Ji Ho , Ko Hyun-Mi , Lee Hyun Joo , Choi Hueng-Sik , Lee Keesook
Published: May 2005

Androgen receptor (AR) is important in male sexual differentiation and testicular function. Here, we demonstrate the regulation of AR expression and its transactivation by the basic helix-loop-helix (bHLH) transcription factor Pod-1, the expression of which in postnatal testis reciprocally coincides with the expression of AR. Pod-1 represses the promoter activity of AR, possibly through its E-box. An AR promoter region of 169 bp, which harbors one canonical E-box, is sufficient for the Pod-1-repression and bound by purified Pod-1 proteins. Pod-1 also suppresses the transactivation of AR. Transient transfection analyses of mammalian cells show that Pod-1 represses AR transactivation in a dose-dependent manner. Furthermore, yeast two-hybrid, glutathione-S-transferase-pull-down, and coimmunoprecipitation analyses reveal that Pod-1 directly associates with AR through its N-terminal region and through the DNA binding-hinge domain of AR. Interestingly, Pod-1 recruits histone deacetylase (HDAC)-1 to inhibit both promoter activity and transactivation of AR. Overexpression of HDAC1 further inhibits the Pod-1-mediated repressions and Pod-1 directly interacts with HDAC1. Furthermore, chromatin immunoprecipitation assay reveals that HDAC1 is recruited with Pod-1 to the endogenous AR promoter and the androgen-regulated Pem promoter. Taken together, these results suggest that Pod-1, which controls AR transcription and function, may play an important role in the development and function of the testis.
Detecting novel low-abundant transcripts in Drosophila
Authors: LEE SANGGYU , BAO JINGYUE , ZHOU GUOLIN , SHAPIRO JOSHUA , XU JINHUA , SHI RUN ZHANG , LU XUEMEI , CLARK TERRY , JOHNSON DEBORAH , KIM YEONG C. , WING CLAUDIA , TSENG CHARLES , SUN MIN , LIN WEI , WANG JUN , YANG HUANMING , WANG JIAN , DU WEI , WU CHUNG-I , ZHANG XIUQING , WANG SAN MING
Published: May 2005

Increasing evidence suggests that low-abundant transcripts may play fundamental roles in biological processes. In an attempt to estimate the prevalence of low-abundant transcripts in eukaryotic genomes, we performed a transcriptome analysis in Drosophila using the SAGE technique. We collected 244,313 SAGE tags from transcripts expressed in Drosophila embryonic, larval, pupae, adult, and testicular tissue. From these SAGE tags, we identified 40,823 unique SAGE tags. Our analysis showed that 55% of the 40,823 unique SAGE tags are novel without matches in currently known Drosophila transcripts, and most of the novel SAGE tags have low copy numbers. Further analysis indicated that these novel SAGE tags represent novel low-abundant transcripts expressed from loci outside of currently annotated exons including the intergenic and intronic regions, and antisense of the currently annotated exons in the Drosophila genome. Our study reveals the presence of a significant number of novel low-abundant transcripts in Drosophila, and highlights the need to isolate these novel low-abundant transcripts for further biological studies.
The REALAB Project: A New Method for the Formulation of Reference Intervals Based on Current Data
Authors: Grossi Enzo , Colombo Roberto , Cavuto Silvio , Franzini Carlo
Published: May 2005

Background: In a primary healthcare center concerned more with maintaining wellness than with diagnosing and monitoring illness, it is particularly important to compare patients’ results with reference intervals derived from a matched population by use of defined statistical methods.

Methods: Laboratory results over a 3-year period (∼15 000 000 records; 197 350 individuals) were retrieved from our laboratory information system. An inclusion/exclusion procedure for individual patients was applied based on (a) presence of at least 1 of 23 previously defined “basic tests”; (b) only 1 measurement per test by the laboratory over the 3-year period; (c) for each test, absence of any abnormality in the correlated tests. Before the third step, correlations among quantities were assessed by a Spearman correlation matrix, comparing each of the 23 basic tests with all remaining tests by use of a novel multivariate algorithm.

Results: The initial sample group (n = 197 350) was reduced stepwise by the selection criteria outlined above to 166 027, then to 93 649, and finally to 61 246 individuals constituting our reference sample group. Results from the last 2 groups were used to calculate sex-specific, and in some cases age-related, reference limits for the 23 basic tests and for 13 additional quantities. Reference limits were calculated throughout this study by nonparametric estimation of percentiles.

Conclusion: Reference values derived by retrospective analysis of large samples of data obtained at a given institution are particularly suitable for the evaluation of results for the presenting patient population at that institution.
Szenarienspezifikation zur Systemverhaltensanalyse mit Petrinetzen (Scenario Specification for the Analysis of System Behaviour by Petri-Nets)
Authors: Einer Stefan
Published: May 2005

Die formale Technik „STOP — Spezifikationstechnik operationaler Prozesse“ dient dazu, Szenarien eines Systems und deren Abweichungspotenzial zu einem analysierbaren Verhaltensmodell des Systems zu synthetisieren. Dazu wurde eine bestimmte Form der Petrinetzmodellierung entwickelt, die hier vorgestellt sowie anhand ihrer praktischen Anwendung veranschaulicht wird.
P- und PD-Polvorgaberegler für Regelstrecken mit begrenzter Stellgröße (P and PD Pole Assignment Controllers for Constrained Systems)
Authors: Huba Mikuláš
Published: May 2005

In diesem Beitrag werden zwei neue Verfahren zum Entwurf von Polvorgabereglern mit beschränkter Stellgröße für Regelstrecken mit einer dominanten Dynamik zweiter Ordnung betrachtet. Die Verfahren liefern einfache und zugleich zuverlässige Entwurfsergebnisse. Sie sind vor allem für die Regelung von instabilen Regelstrecken und für hohe Qualitätsansprüche an das dynamische Verhalten und an den stationären Zustand des Regelkreises bestimmt. Zuerst wird gezeigt, dass bei der Regelung von Strecken erster Ordnung die Stellgrößenbeschränkung zu keinen parasitären Nebenwirkungen wie Überschwingen, Oszillationen oder Instabilität führt. Im Fall von Strecken höherer Ordnung versucht man daher, die Regelungsaufgabe auf mehrere Teilaufgaben erster Ordnung zurückzuführen. Die Lösung dieser Aufgabe ist im Fall von reellen Polen möglich (obwohl nicht eindeutig).

Im Fall von komplexen Polen wird eine prinzipiell andere Möglichkeit genutzt. Durch eine nichtlineare Anpassung des Sollwertes wird die Zustandstrajektorie an eine optimale Bremskurve angenähert. Dies kann durch einfaches Gain-Scheduling ergänzt werden, um mögliche Zeitverzögerungen des Regelkreises in der Beschleunigungsphase zu kompensieren. Kombiniert man solche Reglerentwürfe, die für den doppelten Integrator durchgeführt wurden, mit einer Approximation der Regelstrecken durch I2PT1 oder I2Tt-Glieder, dann erhält man eine einfache und leicht benutzbare Methode für den Reglerentwurf mit Berücksichtigung von Begrenzungen und Zeitverzögerungen, die als eine Erweiterung des Verfahrens nach Ziegler und Nichols angesehen werden kann.
Ermittlung des Nutzens von Datenbankreorganisationen: Notwendigkeit, Werkzeuge, Herangehensweisen (Ascertaining the Benefit of Database Reorganizations: Need, Tools, Procedures)
Authors: Dorendorf Stefan
Published: May 2005

Um auch bei einer großen Menge zu verwaltender Daten einen hohen Durchsatz und ein gutes Antwortzeitverhalten zu bieten, werden bei modernen Datenbank-Management-Systemen bei Update-Operationen die physischen Strukturen zur Speicherung von Daten und Zugriffspfaden oftmals von den Produkten nicht sofort oder nicht vollständig gepflegt. Damit entstehen sukzessive Degenerierungen in den Strukturen, die sich negativ auf Speicherauslastung und Systemleistung auswirken können. Solche Degenerierungen können mit Datenbankreorganisationen beseitigt werden. Bevor jedoch eine solche meist aufwändige und die laufende Datenbankverarbeitung möglicherweise behindernde Reorganisation durchgeführt wird, ist es notwendig, Degenerierungen zu erkennen und zu lokalisieren. Weiterhin ist es wünschenswert, die Auswirkungen der Degenerierungen und den durch eine Reorganisation erreichbaren Nutzen einschätzen (quantifizieren) zu können. Dieser Beitrag beleuchtet einige Aspekte des Themengebietes Datenbankreorganisation und zeigt Vorgehensweisen, die im Rahmen von Reorganisationsbedarfsanalysen und Reorganisationsnutzenanalysen angewendet werden können, und betrachtet dabei auch derzeit am Markt verfügbare Produkte.
The neuroendocrine timing of puberty
Authors: Ebling Francis J P
Published: May 2005

Puberty is the attainment of fertility, a process encompassing morphological, physiological and behavioural development. The increased hypothalamic secretion of the gonadotrophin-releasing hormone decapeptide (GnRH) is essential for the activation of the pituitary–gonadal axis at puberty. The GnRH secretory network initially develops and is temporarily active during species-specific periods of fetal/neonatal development, so puberty is the secondary reactivation of an existing system. From a neurobiological perspective, the timing of puberty is therefore a function of changes in the neural systems controlling GnRH release. The large variability between individuals in the onset and progression of puberty indicates that the timing of puberty is not simply a function of chronological age. Rather, the neurotransmitter and neuromodulatory systems that impact upon the GnRH secretory network convey information about metabolic fuels, energy stores and somatic development and, for many species, information about season and social environment. The clear links demonstrated between metabolic fuel availability and reproductive function in many animal models provides evidence that the earlier onset of pubertal development observed in girls in certain US study populations is likely to relate to the increasing prevalence of overweight and obesity in adolescents.
OCTN2-mediated transport of carnitine in isolated Sertoli cells
Authors: Kobayashi Daisuke , Goto Akihiko , Maeda Tomoji , Nezu Jun-ichi , Tsuji Akira , Tamai Ikumi
Published: May 2005

Carnitine is extensively accumulated in epididymis. Carnitine is also accumulated in testis at higher concentration than in the plasma and is used in spite of the presence of the blood–testis barrier. In this study, we examined the characteristics of carnitine transport in primary-cultured rat Sertoli cells, which constitute a part of the blood–testis barrier. Uptake of [3H]carnitine (11.4 nM) from the basal side of Sertoli cells was Na+-dependent and was significantly decreased in the presence of 10 μM (48.0 ± 7.4% of control) or 100 μM unlabeled carnitine (14.6 ± 5.7% of control). Furthermore, the uptake was significantly inhibited in the presence of 100 μM acetyl-L-carnitine, 100 μM gamma-butyrobetaine or 500 μM quinidine. In RT-PCR analysis, the high-affinity carnitine transporter OCTN2 was detected in rat whole testis tissue and primary-cultured Sertoli cells. In contrast, the low-affinity carnitine transporter ATB0,+was detected in rat whole testis tissue, but not in primary cultured Sertoli cells. These results demonstrate that OCTN2 mediates carnitine supply to Sertoli cells from the circulation.
Capacitation-associated protein tyrosine phosphorylation and membrane fluidity changes are impaired in the spermatozoa of asthenozoospermic patients
Authors: Buffone Mariano G , Calamera Juan C , Verstraeten Sandra V , Doncel Gustavo F
Published: May 2005

Sperm protein tyrosine phosphorylation has been associated with capacitation, motility changes, zona binding, and fertilizing ability. We previously demonstrated that gradient-isolated human sperm subpopulations differ in their plasma membrane composition, their ability to phosphorylate proteins in tyrosine residues, and their capacity to undergo hyperactivation. In this study, we have characterized capacitation-associated changes in protein tyrosine phosphorylation and membrane fluidity in spermatozoa of asthenozoospermic and normozoospermic patients consulting for infertility. Semen samples were studied at baseline and after a capacitating incubation with or without the addition of a permeable cAMP analog and a phosphodiesterase inhibitor. Basic sperm and computer-assisted motion parameters, hyperactivation, protein tyrosine phosphorylation (immunofluorescence and Western blot), and membrane fluidity (fluorescent Laurdan probe) were the main study parameters. In comparison with normozoospermic and proven-fertile donor semen, asthenozoospermic samples showed lower motility, velocity, and amplitude of lateral head displacement, both originally and after a 6-h capacitating incubation. Unlike those in normal samples, asthenozoospermic spermatozoa were unable to increase protein tyrosine phosphorylation during capacitation. Such impairment, however, was overcome when they were incubated with a membrane-permeable cAMP analog and a phosphodiesterase inhibitor, indicating a possible membrane defect. Confirming this hypothesis, plasma membranes of asthenozoospermic sperm showed decreased fluidity (increased Laurdan polarization), even after a capacitating incubation. In conclusion, spermatozoa from functional asthenozoospermic samples may owe their poor motility, and their inability to properly capacitate and develop hyperactivation, to an impairment in the tyrosine phosphorylation of critical proteins caused by decreased membrane fluidity. These findings suggest a molecular pathogenetic mechanism for a common seminal pathology associated with male infertility.
The role of progesterone in endometrial angiogenesis in pregnant and ovariectomised mice
Authors: Walter Lisa M , Rogers Peter A W , Girling Jane E
Published: May 2005

The role of progesterone (and oestrogen) in endometrial angiogenesis remains controversial. The aims of this study were to quantify endometrial angiogenesis in pregnant mice and to investigate the role of progesterone in promoting endothelial cell proliferation in ovariectomized mice. Uteri were collected on days 1 to 4 of pregnancy when circulating progesterone concentrations were increasing, prior to implantation. Before dissection, mice were injected with bromodeoxyuridine (BrdU) enabling proliferating endothelial cells to be quantified with CD31/BrdU double-immunohistochemistry. There was a significant increase in proliferating endothelial cells on day 3 of pregnancy when plasma progesterone also increased. To determine if this endothelial cell proliferation was due to progesterone, an experiment was performed on ovariectomised mice. One group was treated with a single oestradiol injection on day 8 after ovariectomy, followed by a no-treatment day and three consecutive daily injections of progesterone. Other groups were treated with either the vehicle, oestradiol or progesterone injections only; all were dissected on day 13 following ovariectomy. Unexpectedly, mice treated with progesterone-only had the highest amount of endothelial cell proliferation and oestrogen priming was found to significantly reduce this progesterone-induced endothelial cell proliferation. To determine if this proliferation is mediated by vascular endothelial growth factor (VEGF), a further experiment in which VEGF anti-serum was administered concurrently with the progesterone injections was performed. Endothelial cell proliferation was reduced but not abolished suggesting progesterone-induced endometrial angiogenesis is only partly mediated by VEGF. Results indicate that oestrogen priming is not required for progesterone to stimulate endometrial endothelial cell proliferation and that oestrogen inhibits progesterone-induced angiogenesis in ovariectomised mice.
External Egg Membrane Characteristics of Landlocked Fall Chinook Salmon Eyed Eggs Treated with Hydrogen Peroxide or Formalin
Authors: Stephenson Hans , Gabel Mark , Barnes Michael E
Published: May 2005

This study examines the microscopic characteristics of external egg membranes from eyed eggs of landlocked fall Chinook salmon Oncorhynchus tshawytscha treated with formalin (1,667 mg/L) or hydrogen peroxide (700 mg/L) for 15 min daily until hatching. Just before the start of hatching, the internus layer became significantly less differentiated in the membranes of eggs treated with hydrogen peroxide compared with those in the formalin treatments or untreated controls. There were no significant differences among the treatments in total membrane thickness, pore canal height, basal layer height, pore canal width, and the number of pore canals per 50-μm lengthwise segment along the membrane. Overall membrane thickness (externus and internus layers combined) averaged 51.5 μm during the test period. Thickness of externus averaged 0.69 μm, nearly two times that reported previously for nonlandlocked Chinook salmon.
Geosmin and 2-Methylisoborneol Cause Off-Flavors in Cultured Largemouth Bass and White Sturgeon Reared in Recirculating-Water Systems
Authors: Schrader Kevin K , Rubio Sonia Acuña , Piedrahita Raul H , Rimando Agnes M
Published: May 2005

Earthy and musty off-flavors were present in the fillets of largemouth bass Micropterus salmoides and white sturgeon Acipenser transmontanus grown in partial water-recirculating aquaculture systems. Solid phase microextraction–gas chromatography–mass spectrometry revealed that geosmin and 2-methylisoborneol in the flesh of these fish caused these off-flavors.
Exposure to Feedborne Mycotoxins T-2 Toxin or Ochratoxin A Causes Increased Mortality of Channel Catfish Challenged with Edwardsiella ictaluri
Authors: Manning Bruce B. , Terhune Jeffery S. , Li Menghe H. , Robinson Edwin H. , Wise David J. , Rottinghaus George E.
Published: May 2005

To evaluate the effect of mycotoxins on the disease resistance of juvenile channel catfish Ictalurus punctatus, we conducted an experiment in aquaria under controlled environmental conditions. Catfish were fed a nutritionally complete semipurified diet containing two concentrations of either T-2 toxin (1.0 or 2.0 mg/kg diet) or ochratoxin A (OA; 2.0 or 4.0 mg/kg diet). Mycotoxins were supplied as pure, crystalline T-2 toxin diluted to a known concentration in a carrier of casein and Aspergillus ochraceus culture material containing a known concentration of OA. After 6 weeks of feeding, catfish were challenged by immersion in situ with a virulent isolate of Edwardsiella ictaluri suspended in nutrient broth that provided an estimated 2.25 × 106 colony forming units per milliliter of water. At 21 d postchallenge, significantly (P < 0.05) greater mortalities occurred among catfish fed T-2 toxin, 1.0 or 2.0 mg/kg diet (84.11% and 99.30%, respectively) than among control fish. Fish fed the OA diet (4.0 mg/kg) also had significantly higher mortality (80.49%) than control-fed catfish, which experienced 68.28% mortality. Results indicate that juvenile channel catfish fed feedborne mycotoxins T-2 toxin or OA had significantly greater mortality when challenged with E. ictaluri.
Pharmacokinetic Studies of Florfenicol in Koi Carp and Threespot Gourami Trichogaster trichopterus after Oral and Intramuscular Treatment
Authors: Yanong Roy P. E. , Curtis Eric W. , Simmons Robert , Bhattaram Venkatesh Atul , Gopalakrishnan Mathangi , Ketabi Nahal , Nagaraja Nelamangala V. , Derendorf Hartmut
Published: May 2005

The pharmacokinetics of florfenicol were studied in koi carp Cyprinus carpio (hereafter, koi) and threespot gourami Trichogaster trichopterus after oral (50 mg/kg) and intramuscular (25 mg/kg) administration of the drug in warm water conditions (24–25°C). The estimates of clearance, volume of distribution, and half-life were 0.05 L · h−1 · kg−1, 1.0 L/kg, and 16 h, respectively, in koi. In threespot gourami, the corresponding estimates were 0.32 L · h−1 · kg−1, 2.0 L/kg, and 4 h. In koi, minimal drug absorption was observed after bath treatment. Analysis of florfenicol leaching from fish feed indicated that about 50–80% of the coated drug is lost and is not available for therapeutic benefit for either species. The minimum inhibitory concentrations of florfenicol, determined for bacterial isolates from tropical fish, ranged from 0.5 to 2 μg/mL. For effective dosing regimens in koi and threespot gourami, the differences in pharmacokinetics should be considered in future studies.