bluuebunny/crossref_metadata_2025 huggingface dataset:
Characteristics of Chinese suicide attempters admitted to a geropsychiatric unit
Authors: Yang Cheng‐Hung , Tsai Shih‐Jen , Chang Jay‐Wen , Hwang Jen‐Ping
Published: August 2002

Purpose

To investigate the characteristics for elderly Chinese suicide attempters in Taiwan and make comparisons with Western reports.

Methods

During a six‐year period, patients admitted to a geropsychiatric unit as a result of a suicide attempt were investigated for factors related to the suicide attempt.

Results

Of the 722 admissions during this period, 55 (7.6%) were patients who had been admitted due to suicide attempt. The sex and age distributions for the suicide attempters were similar to those for other patients. The most common diagnoses were depressive disorders (56.4%), followed by delusional disorders (20.0%). A total of 121 suicide motives were cited for the 55 attempters, an average of 2.2 per person, with depressive symptoms commonly found on admission. During the first week of hospitalization, 53 attempters (96.4%) still exhibited suicidal ideation and six patients made a further suicide attempt, however, only three patients retained suicidal ideation on discharge.

Conclusions

Our study confirms previous Western reports that depressive disorders are commonly manifested in elderly suicide attempters. There were differences in the motives and methods employed for the suicides, possibly due to cultural difference and/or sample source. Most of the suicide attempters exhibited a favourable response with hospitalization. Copyright © 2001 John Wiley & Sons, Ltd.
Policies, principles and pragmatism: old age psychiatrists' attitudes and practice regarding influenza immunisation for long stay patients
Authors: Holloway Guy
Published: August 2002

This study aimed to examine the attitudes and practice of old age psychiatrists with respect to influenza immunisation for their patients in long stay care. A questionnaire was mailed out with a copy of the government immunisation policy.

There was considerable disagreement among responders regarding the government policy, quality of life issues and the appropriateness of immunisation. There was a consensus in favour of immunising those who could not consent and for seeking relatives' views in this scenario. Staff immunisation status and patients' prior wishes were highlighted, amongst other factors, as affecting immunisation decisions. The government policy might be more acceptable to psychiatrists if there was more emphasis on the individual nature of clinical decisions and the policy will have to change in the light of new legislation. Copyright © 2002 John Wiley & Sons, Ltd.
Unusually large reactivity differences in the transformation of cyclopropane lactones to 1‐aminocyclopropane‐1‐phosphonic acids and their carboxylic acid analogues
Authors: Jászay Zsuzsa M. , Keserű György M. , Clementis György , Petneházy Imre , Kováts Katalin , Tőke László
Published: August 2002

Starting from a cyclopropane lactone 5, the synthesis of a 1‐aminocyclopropane‐1‐phosphonic acid derivative 11 is described. The considerable differences in the reactivity of the lactone ring opening in the case of a cyclopropane lactone substituted by a phosphonic acid ester 5 and their carboxylic acid ester analogue 2 toward ammonia or amines have been compared and interpreted by using the map of electrostatic potentials. © 2001 John Wiley & Sons, Inc. Heteroatom Chem 12:90–96, 2001
TPM—Total Productive Maintenance: Impact on competitiveness and a framework for successful implementation
Authors: Park K.S. , Han S.W.
Published: August 2002

Total Productive Maintenance (TPM) describes a synergistic relationship among all organizational functions, but particularly between production and maintenance, for continuous improvement of product quality, operational efficiency, capacity assurance, and safety. This article provides the key factors that are critical to the successful implementation of TPM. It is thus crucial to provide and discuss those factors for more effective TPM implementation. Also, this study explores the impact of TPM on the competitiveness of the company. This research concludes that long‐term benefits of TPM are the result of considerable investment in human resource development and management. For TPM practitioners, we advise to build a supportive culture and environment with a strong emphasis on human and organizational aspects to promote effective TPM implementation. © 2001 John Wiley & Sons, Inc.
Cognitive effects of a Ginkgo biloba/vinpocetine compound in normal adults: systematic assessment of perception, attention and memory
Authors: Polich John , Gloria Rebecca
Published: August 2002

A computerized test battery was used in a double‐blind design to assess the cognitive effects of a nutrient compound containing Ginkgo biloba in 24 normal adults. Ten tasks (perceptual, attention and short‐term memory) were presented in a standardized manner designed to maximize performance, with substantial pre‐test practice employed to minimize response variability. Subjects were given either placebo or Ginkgo biloba extract capsules to consume for 14 days, after which they performed all tasks twice. They then received the other condition, and after 14 days completed the final test session. Response time and error rate stabilized after pre‐test practice. A ‘working memory capacity’ paradigm demonstrated a reliable 50 ms response time decrease between the placebo and Ginkgo biloba testing, suggesting that Ginkgo biloba speeds short‐term working memory processing in normal adults. Copyright © 2001 John Wiley & Sons, Ltd.
Theory, development, and applicability of the surface water hydrologic model CASC2D
Authors: Downer Charles W. , Ogden Fred L. , Martin William D. , Harmon Russell S.
Published: August 2002

Numerical tests indicate that Hortonian runoff mechanisms benefit from scaling effects that non‐Hortonian runoff mechanisms do not share. This potentially makes Hortonian watersheds more amenable to physically based modelling provided that the physically based model employed properly accounts for rainfall distribution and initial soil moisture conditions, to which these types of model are highly sensitive. The distributed Hortonian runoff model CASC2D has been developed and tested for the US Army over the past decade. The purpose of the model is to provide the Army with superior predictions of runoff and stream‐flow compared with the standard lumped parameter model HEC‐1. The model is also to be used to help minimize negative effects on the landscape caused by US armed forces training activities. Development of the CASC2D model is complete and the model has been tested and applied at several locations. These applications indicate that the model can realistically reproduce hydrographs when properly applied. These applications also indicate that there may be many situations where the model is inadequate. Because of this, the Army is pursuing development of a new model, GSSHA, that will provide improved numerical stability and incorporate additional stream‐flow‐producing mechanisms and improved hydraulics. Copyright © 2002 John Wiley & Sons, Ltd.
Stable isotopes in river ice: identifying primary over‐winter streamflow signals and their hydrological significance
Authors: Gibson J. J. , Prowse T. D.
Published: August 2002

The process of isotopic fractionation during freezing in the riverine environment is discussed with reference to a multi‐year isotope sampling survey conducted in the Liard–Mackenzie River Basins, northwestern Canada. Systematic isotopic patterns are evident in cores of congelation ice (black ice) obtained from rivers and from numerous tributaries that are recognized as primary streamflow signals but with isotope offsets close to the equilibrium ice–water fractionation. The results, including comparisons with the isotopic composition of fall and spring streamflow measured directly in water samples, suggest that isotopic shifts during ice‐on occur due to gradual changes in the fraction of flow derived from groundwater, surface water and precipitation sources during the fall to winter recession. Low flow isotopic signatures during ice‐on suggest a predominantly groundwater‐fed regime during late winter, whereas low flow isotopic signatures during ice‐off reflect a mixed groundwater‐, surface water‐ and precipitation‐fed regime during late fall. Copyright © 2002 John Wiley & Sons, Ltd.
Detection of peptide‐specific cytotoxic T‐lymphocyte precursors used for specific immunotherapy of pancreatic cancer
Authors: Suzuki Nobuaki , Maeda Yoshiaki , Tanaka Shoko , Hida Naoya , Mine Takashi , Yamamoto Koutaro , Oka Masaaki , Itoh Kyogo
Published: August 2002

The prognosis of pancreatic cancer is extremely poor with a 5‐year survival of approximately 3%. Thus, the development of new treatment modalities, including a specific immunotherapy, is required. Our study investigated whether cytotoxic T‐lymphocyte (CTL) precursors reacting to peptides with vaccine candidates (13 peptides for HLA‐A2+ or ‐A24+ patients, respectively) were detectable in the prevaccination peripheral blood mononuclear cells (PBMCs) of 15 pancreatic cancer patients. Peptide‐specific CTL precursors were detectable in the majority (11 of 15, 73%) of patients, with a mean positive number of 1.5 peptides (ranging from 0–5 peptides) per patient. Positive peptide profiles varied among patients. These results may provide a scientific basis for a new kind of cancer immunotherapy, namely, a CTL precursor‐oriented peptide vaccine, for pancreatic cancer patients. © 2001 Wiley‐Liss, Inc.
Height, weight, menstrual and reproductive factors and risk of gastric cancer among Japanese postmenopausal women: Analysis by subsite and histologic subtype
Authors: Inoue Manami , Ito Lucy S. , Tajima Kazuo , Yamamura Yoshitaka , Kodera Yasuhiro , Takezaki Toshiro , Hamajima Nobuyuki , Hirose Kaoru , Kuroishi Tetsuo , Tominaga Suketami
Published: August 2002

To clarify whether reproductive factors have an impact on gastric cancer in Japanese females, a case‐control study was conducted using data from the Hospital‐based Epidemiologic Research Program at Aichi Cancer Center (HERPACC), Japan. The study subjects included 365 postmenopausal women with gastric cancer and 1,825 age‐class frequency‐matched noncancer outpatients presenting at Aichi Cancer Center in 1988–1998. Cases were further divided with regard to the anatomic subsite (upper third, middle third, lower third) and histologic subtypes (differentiated, nondifferentiated) and the association was evaluated using odds ratios (ORs) estimated by the logistic regression model, adjusting for potential confounding factors. A high body weight and corresponding body mass index at age 20 moderately increased the risk of gastric cancer, especially for middle third and nondifferentiated cancers. Risk fluctuation with early or late age at menarche and menopause and total duration of fertility was not consistent. Individuals with a high age at first parity tended to show decreased risk of cancer, irrespective of their subsite or histologic subtype. The ORs were decreased with a short average period of breastfeeding, especially for upper third and nondifferentiated cancers. From these results, however, it appears that height, weight, menstrual and reproductive factors have less impact on gastric cancer than environmental factors such as smoking and dietary habits or family history of gastric cancer. © 2001 Wiley‐Liss, Inc.
Altered adhesion properties and alpha v integrin expression in a cisplatin‐resistant human ovarian carcinoma cell line
Authors: Maubant Sylvie , Cruet‐Hennequart Séverine , Poulain Laurent , Carreiras Franck , Sichel François , Luis José , Staedel Cathy , Gauduchon Pascal
Published: August 2002

In order to elucidate the mechanisms underlying the development of chemoresistance in ovarian cancer, we have previously established the IGROV1‐R10 cisplatin‐resistant cell line by mimicking a clinical protocol of drug administration on IGROV1 human ovarian carcinoma cells. Both IGROV1 and IGROV1‐R10 cells were able to grow as a monolayer and to release cell clusters into the medium. However, IGROV1‐R10 cells exhibited an enhanced capacity to detach from the monolayer as compared to the parental cells. When substrate adhesion was prevented, IGROV1‐R10 cells were able to survive and to proliferate as cell clusters, even at a low cell density, whereas IGROV1 cells massively died. To explore the underlying mechanisms, we have been interested in αv integrins, which have been implicated in some aspects of ovarian cancer biology. Both IGROV1 and IGROV1‐R10 adherent cells expressed αvβ3 integrin. During cell growth, αvβ5 integrin accumulated at the surface of a majority of IGROV1‐R10 cells from the monolayer, whereas only a faint expression of this integrin was observed in a minority of IGROV1 cells. The growth of IGROV1‐R10 cells, but not of IGROV1 cells, was partly inhibited by a specific αvβ5‐blocking antibody suggesting that αvβ5 integrin contributed to IGROV1‐R10 cell proliferation. © 2002 Wiley‐Liss, Inc.
Effects of agricultural land use changes on diffuse pollution of water resources
Authors: Meissner R. , Seeger J. , Rupp H.
Published: August 2002

Lysimeter trials carried out over several years showed that cutting mineral fertilizer by 50% does not immediately result in a reduction of the leaching losses of relevant macronutrients (N, P, K). Land usage changes in the form of 1‐year rotating set‐asides entail greater N‐leaching compared to best management practices (BMP). By contrast, after set‐aside lasting 3–5 years, reductions in N‐leaching of 25–45% must be expected. Lysimeter trials of reintegrating land set‐aside for a number of years into intensive agriculture without increasing N‐leaching losses are presented. Ways of scaling up lysimeter results to fields and small catchments are described, as well as areas where research still needs to be carried out are discussed. Copyright © 2002 John Wiley & Sons, Ltd.
Effects of Ginkgo biloba extract on the proliferation of vascular smooth muscle cells in vitro and on intimal thickening and interleukin‐1β expression after balloon injury in cholesterol‐fed rabbits in vivo
Authors: Lin Shing‐Jong , Yang Tzu‐Hsuan , Chen Yung‐Hsiang , Chen Jaw‐Wen , Kwok Ching‐Fai , Shiao Ming‐Shi , Chen Yuh‐Lien
Published: August 2002

Restenosis may develop in response to cytokine activation and smooth muscle cell proliferation. Ginkgo biloba extract (EGb) has been used to treat cardiovascular and cerebrovascular diseases. In the present study, the effects of EGb on the growth of cultured vascular smooth muscle cells (VSMC), as well as on the expression of interleukin‐1β (IL‐1β) and the intimal response in balloon‐injured arteries of cholesterol‐fed rabbits, were investigated. Using bromodeoxyuridine incorporation as an index of cell proliferation, EGb was found to inhibit serum‐induced mitogenesis of cultured rat aorta VSMC in a dose‐dependent manner. In vivo, EGb and probucol ( positive control) reduced the atheroma area in thoracic aortas of male New Zealand white rabbits fed a 2% cholesterol diet for 6 weeks with balloon denudation of the abdominal aorta being performed at the end of the third week. Intimal hyperplasia, expressed as the intimal/medial area ratio, in the abdominal aortas was significantly inhibited in the both the EGb group (0.61 ± 0.06) and the probucol group (0.55 ± 0.03) compared to the C group (0.87 ± 0.02). In the balloon‐injured abdominal aorta, both EGb and probucol significantly reduced IL‐1β mRNA and protein expression and the percentage of proliferating cells. The inhibitory effects of EGb on the intimal response might be attributed to its antioxidant capacity. EGb may have therapeutic potential for the prevention of restenosis after angioplasty. J. Cell. Biochem. 85: 572–582, 2002. © 2002 Wiley‐Liss, Inc.
Effects of zinc on cell proliferation and proteoglycan characteristics of epiphyseal chondrocytes
Authors: Rodríguez J. Pablo , Rosselot Gastón
Published: August 2002

Zinc has been postulated as an important nutritional factor involved in growth promotion; however, the cellular mechanisms involved in the effects of zinc on linear growth remain to be elucidated. This study was conducted to evaluate the effects of zinc on the proliferation rate of epiphyseal growth plate chondrocytes and on the structural characteristics of the proteoglycans synthesized by these cells. For these purposes, hypertrophic and proliferating chondrocytes were isolated from the tibiae of 1‐ and 5‐week‐old chickens, respectively. Chondrocytes were cultured under serum‐free conditions and primary cultures were used. The results showed that zinc stimulated proliferation by 40–50% above the baseline in the case of proliferating chondrocytes, but it had no effect on hypertrophic chondrocytes. Zinc had neither any effects on mean charge density of proteoglycans synthesized by hypertrophic chondrocytes nor in their hydrodynamic size. In contrast, zinc induced an increase in mean charge density and a decrease of hydrodynamic size of proteoglycans synthesized by proliferating chondrocytes. In both cell types zinc had no effect on the composition and hydrodynamic size of the glycosaminoglycan chains. The increased ability of proliferating chondrocytes cultured in the presence of zinc to synthesize 3′‐phosphoadenosine 5′‐phosphosulfate (PAPS) could be explained by the induction of enzymes participating in the sulfation pathway of proteoglycans. Therefore, the increase in mean charge density of proteoglycans observed in this study may be explained by an increase of the degree of sulfation of proteoglycan molecules. We speculate that the effect of zinc on linear growth may be explained at a cellular level by: a) an increase in proliferation rates of proliferating chondrocytes, and b) increased synthesis of highly charged proteoglycan molecules which decreases mineralization. J. Cell. Biochem. 82:501–511, 2001. © 2001 Wiley‐Liss, Inc.
Androgen stimulated cellular proliferation in the human prostate cancer cell line LNCaP is associated with reduced retinoblastoma protein expression
Authors: Taneja Samir S. , Ha Susan , Garabedian Michael J.
Published: August 2002

To elucidate the mechanism of androgen‐dependent cellular proliferation in prostate cancer, androgen‐dependent alterations of individual cell cycle regulatory proteins in the androgen‐sensitive prostate cancer cell line LNCaP were evaluated. LNCaP cells were deprived of androgens by culture in steroid‐depleted media for 5 days, which resulted in the maximal accumulation of cells in G0/G1 phase of the cell cycle. The mitogenic concentration of the synthetic androgen R1881 was established as 0.1 nM using cell proliferation assay. Protein and mRNA levels of particular cyclins, cyclin‐dependent kinases (Cdks), cyclin‐dependent kinase inhibitors (Ckis), and the retinoblastoma proteins (Rb) were assessed. Androgen stimulation resulted in a post‐transcriptional reduction in Rb protein levels, an increase in Rb phosphorylation at serine 780 and an accumulation of high molecular weight Rb protein species. Androgen stimulation also induced the expression of the Cdk2 and Cdk1 as well as their regulatory partners, cyclin A and cyclin B, resulting in a corresponding increase in cyclin A/Cdk2 activity in vitro. Pulse‐chase showed decreased Rb protein stability in androgen‐treated LNCaP cells. Collectively, our findings suggest a novel mechanism of androgen‐dependent prostate cancer growth in which androgen stimulation results in decreased Rb protein expression in LNCaP cells. The observation of decreased Rb protein stability in the setting of increased phosphorylation supports the concept of phosphorylation mediated protein degradation. We propose that the observed reduction in Rb protein level occurs through Rb degradation via the ubiquitin/proteasome pathway, and is preceded by selective Rb phosphorylation by cyclin A/Cdk2 and cyclin B/Cdk1. J. Cell. Biochem. 84: 188–199, 2002. © 2001 Wiley‐Liss, Inc.
A technique for constructing non‐embeddable quasi‐residual designs
Authors: Ionin Yury J. , Mackenzie‐Fleming Kirsten
Published: August 2002

We propose a technique for constructing two infinite families of non‐embeddable quasi‐residual designs as soon as one such design satisfying certain conditions exists. The main tools are generalized Hadamard matrices and balanced generalized weighing matrices. Starting with a specific non‐embeddable quasi‐residual 2‐(27,9,4) design, we construct for every positive integer m a non‐embeddable 2‐(3m,3m−1,(3m−1−1)/2)‐design, and, if rm=(3m−1)/2 is a prime power, we construct for every positive integer n a non‐embeddable $2-(3^m(r^n_m-1)/(r_m-1), 3^{m-1}r^{n-1}_m, (3^{m-1}-1)r^{n-1}_m/2)$ design. For each design in these families, a symmetric design with the corresponding parameters is known to exist. © 2002 Wiley Periodicals, Inc. J Combin Designs 10: 160–172, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jcd.900
Identification of human enterovirulent Escherichia coli strains by multiplex PCR
Authors: Rich Chantal , Alfidja Assalama , Sirot Jacques , Joly Bernard , Forestier Christiane
Published: August 2002

Some strains of Escherichia coli are involved in enteric infections in both adults and children. However the classical diagnostic methods can not differentiate pathogenic from nonpathogenic E. coli, because of the lack of phenotypic differences. In this study, we developed multiplex PCR in order to amplify fragments of specific virulence genes of the five main E. coli pathotypes. Fragments of the expected size were obtained using previously or newly designed primers and allowed identification of 10 virulence genes in only 5 reactions. This method was applied to the detection of pathogenic E. coli isolated from 90 patients’ stools specimens during an 18‐month survey. Patients were suffering from diarrhea or hemolytic uremic syndrome and in 13 cases (14.4%), an enterovirulent E. coli strain was detected. This diagnostic method could therefore represent an important technique in clinical laboratories which lack standard tests for these pathogens. J. Clin. Lab. Anal. 15:100–103, 2001. © 2001 Wiley‐Liss, Inc.
Training for prescriptions vs. prescriptions for training: Where are we now? Where should we be? How do we get there?
Authors: McFall Richard M.
Published: August 2002

The proposal that state legislatures should grant prescription privileges to psychologists is examined critically, with particular attention to the proposal's implications for the future education and training of clinical psychologists. First, the current status of clinical psychology is described. Then, an alternative to the prescription privilege proposal is presented; this alternative prescribes a scientific approach to clinical psychology. Finally, a plan for achieving this alternative is outlined. © 2002 Wiley Periodicals, Inc. J Clin Psychol 58: 659–676, 2002.
Concluding remarks on the debate about prescription privileges for psychologists
Authors: Heiby Elaine M.
Published: August 2002

This article summarizes the six primary arguments for and against prescription privileges for psychologists (PPP or RxP) that were presented in this special issue. Four articles addressed points made in the testimony in favor of PPP by the American Psychological Association. Six articles addressed points in the testimony against PPP by the American Association of Applied and Preventive Psychology. It is concluded that the PPP debate reflects a deep schism in clinical psychology that represents a serious disunity in the field. The disunity is seen as a divide between those trained to be psychotherapists and those trained to be scientist–practitioners. It is argued that the former support PPP and are interested in the survival of professional schools, while the latter oppose PPP and are interested in the survival of university departments of psychology. For the discipline to survive there must be a rapprochement between these factions and alternatives to PPP for the retraining of psychotherapy practitioners. © 2002 Wiley Periodicals, Inc. J Clin Psychol 58: 709–722, 2002.
Effects of mast cells on the behavior of isolated heart fibroblasts: Modulation of collagen remodeling and gene expression
Authors: de Almeida Angela , Mustin Deanna , Forman Mary F. , Brower Gregory L. , Janicki Joseph S. , Carver Wayne
Published: August 2002

The extracellular matrix plays a critical role in the development and maintenance of the vertebrate heart. Changes in the accumulation, composition, or organization of the extracellular matrix are known to deleteriously affect heart function. Mast cells are thought to stimulate collagen expression and fibroblast proliferation accompanying fibrosis in some organs; however, the effects of mast cells on the heart interstitium are largely unexplored. The present studies were carried out to determine the effects of mast cells on isolated heart fibroblasts. Several in vitro assays were used including collagen gel contraction to examine the effects of mast cells on the function of isolated fibroblasts. Neonatal heart fibroblasts were cultured either with mast cells, mast cell‐conditioned medium, or mast cell extracts, and their ability to contract collagen gels measured. Results from these experiments indicated that mast cells inhibit heart fibroblast migration and contraction of 3‐dimensional collagen gels. Further experiments indicated that incubation of neonatal heart fibroblasts with extracts of mast cells altered the expression of collagen, matrix metalloproteases, and matrix receptors of the integrin family. These studies suggest that mast cells play an important role in the regulation of the cardiac interstitial matrix. Further studies are warranted to determine the mechanisms whereby mast cells modulate fibroblast activity. J. Cell. Physiol. 191: 51–59, 2002. © 2002 Wiley‐Liss, Inc.
Epidermal growth factor stimulates serine/threonine phosphorylation of the focal adhesion protein paxillin in a MEK‐dependent manner in normal rat kidney cells
Authors: Terfera David R. , Brown Michael C. , Turner Christopher E.
Published: August 2002

Epidermal growth factor (EGF)‐stimulated proliferation of renal epithelial cells plays an important role in the recovery of kidney tubule epithelia following exposure to insult. Numerous studies have demonstrated that tyrosine phosphorylation of the focal adhesion protein paxillin mediates in part the effects of growth factors on cell growth, migration, and organization of the actin‐based cytoskeleton. The experiments in this report were designed to determine the effect of EGF on paxillin phosphorylation in normal rat kidney (NRK) epithelial cells. Interestingly, treatment of NRK cells with EGF stimulated paxillin serine/threonine phosphorylation, which caused a reduction in the mobility of paxillin on sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS–PAGE). The EGF‐stimulated mobility shift of paxillin was independent of an intact cytoskeleton, phosphatidylinositol 3‐kinase (PI 3‐kinase) activation, protein kinase C (PKC) activation, and cellular adhesion. However, inhibitors of the mitogen‐activated protein kinase/extracellular signal‐regulated kinase kinase abrogated the EGF‐stimulated change in paxillin mobility. In addition, the EGF‐stimulated change in paxillin serine/threonine phosphorylation was not accompanied by a profound reorganization of the actin cytoskeleton. These results identify paxillin as a component EGF signaling in renal epithelial cells and implicate members of the MAP kinase pathway as critical regulators of paxillin serine/threonine phosphorylation. J. Cell. Physiol. 191: 82–94, 2002. © 2002 Wiley‐Liss, Inc.
Mismatch repair in correction of replication errors and processing of DNA damage
Authors: Aquilina Gabriele , Bignami Margherita
Published: August 2002

The primary role of mismatch repair (MMR) is to maintain genomic stability by removing replication errors from DNA. This repair pathway was originally implicated in human cancer through an association between microsatellite instability in colorectal tumors in hereditary nonpolyposis colon cancer (HNPCC) kindreds. Microsatellites are short repetitive sequences which are often copied incorrectly by DNA polymerases because the template and daughter strands in these regions are particularly prone to misalignment. These replication‐dependent events create loops of extrahelical bases which would produce frameshift mutations unless reversed by MMR. One consequence of MMR loss is a widespread expansion and contraction of these repeated sequences that affects the whole genome. Defective MMR is therefore associated with a mutator phenotype. Since the same pathway is also responsible for repairing base:base mismatches, defective cells also experience large increases in the frequency of spontaneous transition and transversion mutations. Three different approaches have been used to investigate the function of individual components of the MMR pathway. The first is based on the biochemical characterization of the purified protein complexes using synthetic DNA substrates containing loops or single mismatches. In the second, the biological consequences of MMR loss are inferred from the phenotype of cell lines established from repair‐deficient human tumors, from tolerant cells or from mice defective in single MMR genes. In particular, molecular analysis of the mutations in endogenous or reporter genes helped to identify the DNA substrates for MMR. Finally, mice bearing single inactive MMR genes have helped to define the involvement of MMR in cancer prevention. © 2001 Wiley‐Liss, Inc.
Endothelin‐1 expression in long‐term cultures of fetal rat calvarial osteoblasts: Regulation by BMP‐7
Authors: Kitten Allison M. , Andrews Carrie J.
Published: August 2002

Endothelin‐1 (ET‐1) is a vasoactive peptide that modulates bone metabolism via regulatory effects on osteoblasts, chondrocytes, and osteoclasts. While ET‐1 may circulate in the blood stream, tissue‐specific expression of this peptide is more physiologically relevant. In the present study we measured ET‐1 synthesis in sections of fetal rat calvaria (FRC) and in cultured FRC osteoblasts. Regulation of ET‐1 synthesis in FRC osteoblasts by bone morphogenetic protein‐7 (BMP‐7) and transforming growth factor‐β1 (TGF‐β1) also was examined. Immunohistochemical analysis revealed ET‐1 staining in calvarial osteoblasts, endothelial cells, and osteocytes. ET‐1 mRNA expression was detected in cultured FRC cells and ET‐1 peptide was present in conditioned media. During long‐term culture of FRC cells (26 days) ET‐1 peptide production rose sharply and peaked during the time of cellular proliferation (Days 0–3) then returned to baseline levels by Day 18, when mineralized nodules were forming. Treatment of FRC cells with BMP‐7 enhanced ET‐1 levels by three‐fold on Day 3 and enhanced nodule formation by 15‐fold on Day 26. To determine whether ET‐1 was involved in an autocrine manner in BMP‐7‐induced nodule formation, cells were cultured in the presence of BMP‐7 and BQ‐123, an ETA receptor antagonist. BQ‐123 had no effect on nodule formation in control or BMP‐7‐treated cells, indicating that osteoblast‐derived ET‐1 regulates other cell types in vivo during the bone formation process. © 2001 Wiley‐Liss, Inc.
Improvement of antibiotic production by increased oxygen solubility through the addition of perfluorodecalin
Authors: Elibol Murat
Published: August 2002

A perfluorocarbon (PFC), namely perfluorodecalin, was added to fermentation medium to increase the medium's oxygen solubility. The antibiotic concentration obtained in the absence of PFC was 45 mg dm−3, whereas it was 90 mg dm−3 in the presence of 10% (v/v) PFC. On the other hand, biomass concentration decreased from 5.7 kg m−3 to 2.9 kg m−3 by adding 10% PFC. The use of PFC in the fermentation medium also reduced the formation of mycelial pellets. The values of the mass transfer coefficient, kLa, measured in the medium with PFC were found to be in the range of 122–175 h−1 during the active growth phase which were two to three times higher than those in the medium containing no PFC. Furthermore, the maximum oxygen uptake rates obtained at the stationary phase with and without PFC were 7 mmol dm−3 h−1 and 4.9 mmol dm−3 h−1, respectively. The actual effect of PFC on actinorhodin fermentation was demonstrated by applying different operational strategies to the system.

© 2001 Society of Chemical Industry
Moisture sorption characteristics of waste activated sludge
Authors: Vaxelaire J
Published: August 2002

Nowadays the treatment of activated sludge often includes a thermal drying step. Data such as water vapour sorption isotherms and heat of sorption are required for good design and control of the drying processes. An equilibrium method was used to measure these data on domestic activated sludge, between 39 °C and 80 °C. The experimental investigation indicated that the nature of the sludge and its evolution (bulking sludge, anaerobic storage) do not affect the sorption isotherms. Experimental data were fitted to different well‐known models; the Oswin relationship gave the better fit. Based on sorption data the heat of sorption as a function of moisture content was determined.

© 2001 Society of Chemical Industry
Incidence and importance of reflux in testicular veins of healthy men evaluated with color duplex sonography
Authors: Kocakoc Ercan , Kiris Adem , Orhan Irfan , Bozgeyik Zulkif , Kanbay Mustafa , Ogur Erkin
Published: August 2002

Purpose

Reflux in the testicular veins plays a crucial role in the diagnosis of a varicocele. The aim of this study was to evaluate the incidence and the sonographic features—duration and velocity—of reflux in testicular veins of healthy men using color duplex sonography (CDS).

Methods

Healthy male volunteers, 18–45 years old, whose physical examinations and semen analyses were normal, were recruited for this study. The maximum diameters of testicular veins during both normal respiration and Valsalva's maneuver were measured by CDS using a 7.5‐MHz linear‐array transducer. Veins greater than 2 mm in diameter were considered to be a varicocele, and the subjects in these cases were excluded from the analysis. In cases in which reflux was present, the velocity and duration of reflux in the testicular veins during Valsalva's maneuver were measured.

Results

Seventy men, whose mean (± standard deviation) age was 27 ± 7 years, were enrolled in this study. Fourteen of the 70 patients had a left varicocele and thus were excluded from the analysis. Of the 112 hemiscrotums in the remaining 56 patients, 61 (54%) had reflux induced by Valsalva's maneuver and 51 (46%) did not. Twenty‐two (39%) of refluxes were on the right side, with a mean duration of 1.1 ± 0.5 seconds, and a mean velocity of 4.2 ± 2.1 cm/second; 39 (70%) of the refluxes were on the left side, with a mean duration of 1.1 ± 0.5 seconds and a mean velocity of 4.9 ± 2.3 cm/second. The incidence of reflux was significantly higher on the left side (p = 0.003). The duration and velocity of the reflux did not differ significantly between the right and left sides. The difference in the testicular vein diameters between the right (1.3 ± 0.2 mm; n = 56) and left (1.6 ± 0.2 mm; n = 56) sides was statistically significant (p < 0.001).

Conclusions

Normal‐sized testicular veins in healthy subjects had a remarkably high incidence of reflux induced by Valsalva's maneuver. The presence of reflux in subfertile men with normal testicular vein diameters is a diagnostic criterion, but it is necessary to quantify the reflux to prevent misdiagnosis of a varicocele and unnecessary surgery. The measurement of the duration and velocity limits of reflux in a large series of subjects may provide a reliable indicator for the diagnosis of varicocele. © 2002 Wiley Periodicals, Inc. J Clin Ultrasound 30:282–287, 2002; Published online in Wiley InterScience (www. interscience.wiley.com). DOI: 10.1002/jcu.10068
Transabdominal sonography of the normal gastroesophageal junction in children
Authors: Esposito Francesco , Lombardi Romilda , Grasso Angela Coppolaro , Dolezalova Hana , Sodano Antonio , Tarantino Luciano , Giorgio Antonio
Published: August 2002

Purpose

Because sonography identifies abnormalities of the gastroesophageal junction, it is essential to understand the normal sonographic anatomy. The aim of this study was to determine the normal sonographic appearance of the gastroesophageal junction and its variations and to provide measurements of the abdominal esophagus in asymptomatic, healthy children.

Methods

In this prospective study, 124 healthy children (75 boys and 49 girls), aged 2 days–12 years, underwent abdominal sonography. With the patient in a supine position, the transducer was placed under the xiphoid and the ultrasound beam was directed cephalad through the window of the left lobe of the liver. The length of the abdominal esophagus was measured from the point at which it penetrated the diaphragm to the gastroesophageal junction. The thickness was measured on the anterior wall at the midpoint of the abdominal esophagus.

Results

The gastroesophageal junction was identified by sonography in all of the children. The mean length of the abdominal portion of the esophagus ranged from 18 mm in the newborns to 34 mm in children older than 6 years. The wall thickness ranged from 2.4 mm to 5.7 mm.

Conclusions

Our results indicate that visualization of the gastroesophageal junction and measurement of the abdominal esophagus are readily achievable with real‐time sonography in healthy children. © 2001 John Wiley & Sons, Inc. J Clin Ultrasound 29:326–331, 2001.
4‐Hydroxynonenal, a lipid peroxidation byproduct of spinal cord injury, is cytotoxic for oligodendrocyte progenitors and inhibits their responsiveness to PDGF
Authors: Gard Anthony L. , Solodushko Victor G. , Waeg Georg , Majic Tamara
Published: August 2002

Oligodendroglial reactions to compression injury of spinal cord include apoptosis, secondary demyelination, and remyelination failure. Within hours after contusion, the membrane lipid peroxidation (MLP) byproduct, 4‐hydroxynonenal (HNE), increases rapidly in gray matter and thereafter in white matter tracts beyond the initial lesion level. Considering that HNE is a mediator and marker of neuronal MLP toxicity in various neurodegenerative conditions, the present study examined its effect on the regeneration potential of oligodendrocyte progenitors, as defined by their capacity to survive, proliferate and migrate in primary culture. Treatment of oligodendroblasts with HNE evoked a time‐ and dose‐dependent cytotoxicity resembling apoptosis at aldehyde concentrations known to be produced by neurons and achieved in tissue undergoing peroxidative injury. In addition, sublethal concentrations of HNE inhibited the mitogenic and chemotactic responses of more immature progenitors to platelet‐derived growth factor. These effects appear to be mediated in part by the formation of HNE adducts with progenitor proteins located within the plasma membrane and cytoplasmic compartments. Our data are the first to show that HNE can have direct, deleterious effects on oligodendrocyte precursors. The present study also suggests a mechanism by which the striking accumulation of HNE in white matter tracts surrounding the site of spinal cord compression injury and in other ischemic‐hypoxic insults associated with MLP could suppress the potential regenerative response of endogenous oligodendrocyte progenitor cells. Microsc. Res. Tech. 52:709–718, 2001. © 2001 Wiley‐Liss, Inc.
Tracking oligodendrocytes during development and regeneration
Authors: Chandross Karen J. , Champagne Benedicte , Auble Kathryn , Hudson Lynn D.
Published: August 2002

Over the past decade, advances in strategies to tag cells have opened new avenues for examining the development of myelin‐forming glial cells and for monitoring transplanted cells in animal models of myelin insufficiency. The strategies for labelling glial cells have encompassed a range of genetic modifications as well as methods for directly attaching labels to cells. Genetically modified oligodendrocytes have been engineered to express enzymatic (e.g., β‐galactosidase, alkaline phosphatase), naturally fluorescent (e.g., green fluorescent protein), and antibiotic resistance (e.g., neomycin, zeomycin) reporters. Genes have been introduced in vivo and in vitro with viral or plasmid vectors to somatically label glial cells. To generate germ‐line transmission of tagged oligodendrocytes, transgenic mice have been created both by direct injection into mouse fertilized eggs and by “knock‐in” of reporters targetted to myelin gene loci in embryonic stem cells. Each experimental approach has advantages and limitations that need to be considered for individual applications. The availability of tagged glial cells has expanded our basic understanding of how oligodendrocytes are specified from stem cells and should continue to fill in the gaps in our understanding of how oligodendrocytes differentiate, myelinate, and maintain their myelin sheaths. Moreover, the ability to select oligodendrocytes by virtue of their acquired antibiotic resistance has provided an important new tool for isolating and purifying oligodendrocytes. Tagged glial cells have also been invaluable in evaluating cell transplant therapies in the nervous system. The tracking technologies that have driven these advances in glial cell biology are continuing to evolve and present new opportunities for examining oligodendrocytes in living systems. Microsc. Res. Tech. 52:766–777, 2001. Published 2001 Wiley‐Liss, Inc.
Microglia and prion disease
Authors: Brown David R.
Published: August 2002

Gliosis is one of the hallmarks of the prion diseases. Prion diseases are fatal neurodegenerative conditions of low incidence made famous by both the hypothesis that a protein acts as the infectious agent without involvement of nucleic acid and the speculative idea that a disease of cattle, BSE, has spread to humans from the ingestion of prion‐infected beef. Despite these unproved hypotheses, the aetiology of the prion diseases remains unsolved. The rapid degenerative course of the disease is preceded by a long incubation period with little or no symptoms. The rapid neurodegeneration in the disease follows from increased deposition of an abnormal isoform of a normal neuronal protein. Co‐incident with the appearance of this abnormal protein is the activation of large numbers of microglia. Studies in cell culture with both the abnormal prion protein and a peptide‐mimic suggest that neuronal degeneration occurs because of two concurrent effects. First, there is a reduction in neuronal resistance to toxic insults and, second, there is an increase in the production of toxic substances such as reactive oxygen species by microglia and a decrease in glutamate clearance by astrocytes. Microglia activated by the abnormal form of the prion protein also release cytokines, which stimulate changes in astrocytes such as proliferation. The implication of this is that microglia may play a major role in initiating the pathological changes in prion disease. This review discusses the role of microglia in these changes. Microsc. Res. Tech. 54:71–80, 2001. © 2001 Wiley‐Liss, Inc.
Catecholamines are present in larval Xenopus laevis: A potential source for cardiac control
Authors: Kloberg Angélica Jacobsson , Fritsche Regina
Published: August 2002

Changes in noradrenaline (NA), adrenaline (A), and dopamine (DA) levels in the heart, kidneys, and whole body (without heart and kidneys) during embryonic development were investigated in the frog, Xenopus laevis using high‐performance liquid chromatography (HPLC). In addition, the presence of cells immunoreactive to tyrosine hydroxylase (TH), dopamine‐β‐hydroxylase (DBH) and/or phenylethanolamine‐N‐methyltransferase (PNMT) in the heart of Xenopus larvae was investigated using immunohistochemical techniques. The presence of nerve fibers was visualized using antibodies against acetylated tubulin (AcT). NA and DA concentrations in the heart were low and steady in NF 40–56, showed an increased value at NF 57, and decreased again in froglets. A trend toward higher concentrations of A was observed at NF 43–49 and NF 57. Cells immunoreactive to TH, DBH, and PNMT were found in the heart from NF 40, and the TH immunoreactive cells became more abundant in the whole heart at later stages. The presence of catecholamines in the non‐innervated larval heart together with the finding of TH/DBH/PNMT immunoreactive cells suggests that catecholamines are synthesized and stored in the heart and could therefore have a paracrine role in cardiac control in Xenopus larvae. Detectable concentrations of catecholamines were also found in kidneys and whole bodies (except heart and kidneys). Therefore, catecholamine‐producing cells outside the heart can be an important source of circulating catecholamines involved in adrenergic cardiac control in Xenopus larvae. J. Exp. Zool. 292:293–303, 2002. © 2002 Wiley‐Liss, Inc.
Membrane currents in the oocyte of the toad Bufo arenarum
Authors: Kotsias Basilio A. , Damiano Alicia E. , Godoy Sebastian , Assef Yanina , Ibarra Cristina , Cantiello Horacio F.
Published: August 2002

The amphibian oocyte cell model is widely used for heterologous expression of ionic channels and receptors. Little is known, however, about the physiology of oocyte cell models other than Xenopus laevis. In this study, the two‐electrode voltage clamp technique was used to assess the most common electrical patterns of oocytes of the South American toad Bufo arenarum. Basal membrane resistance, resting potential, and ionic currents were determined in this cell model. The oocyte transmembrane resistance was 0.35 MΩ, and the resting potential in normal saline was about –33 mV with a range between –20 mV and –50 mV. This is, to our knowledge, the first attempt to begin an understanding of the ion transport mechanisms of Bufo arenarum oocytes. This cell model may provide a viable alternative to the expression of ion channels, in particular those endogenously observed in Xenopus laevis oocytes. J. Exp. Zool. 292:411–415, 2002. © 2002 Wiley‐Liss, Inc.
Steroid enzyme gene expressions during natural and androgen‐induced gonadal differentiation in the rainbow trout, Oncorhynchus mykiss
Authors: Govoroun Marina , McMeel Oonagh Marie , D’Cotta Helena , Ricordel Marie‐José , Smith Terry , Fostier Alexis , Guiguen Yann
Published: August 2002

In fish, according to Yamamoto’s model, androgens would drive testis differentiation and estrogens ovarian differentiation. In order to study the implication of steroid enzymes in rainbow trout gonadal differentiation, we examined the expression of some steroid enzyme genes during natural differentiation (cholesterol side chain cleavage = P450scc, 17‐hydroxylase/lyase = P450c17, 3β‐hydroxysteroid dehydrogenase = 3βHSD) and androgen‐induced differentiation (P450scc, P450c17 , 3βHSD, aromatase = P450aro, and 11β‐hydroxylase = P45011β). Expressions of P450scc, 3βHSD, and P450c17 were all detected in male and female gonads at 55 days post‐fertilization (dpf), i.e., two weeks before histological differentiation. There were no differences in their expression level respective to the sex. The androgen treatment was carried out by administration of 11β‐hydroxyandrostenedione (11βOHΔ4) in genetic all‐female populations and the resulting sex ratios were found to be 100% male even at a low dosage of 1 mg/kg of food. Following 11βOHΔ4 treatment, only the expression of P450c17 was found to be sustained when compared with the female untreated control. In contrast, P450scc was clearly up‐regulated and 3βHSD and P450aro down‐regulated by the androgen treatment. P45011β gene expression remained low in gonads of androgen‐treated females, as it did in control untreated females. These results together demonstrate that steroidogenesis in rainbow trout is potentially active in pre‐differentiating gonads of both sexes, and that one of the masculinizing actions of androgens in the species may be to down‐regulate the female‐specific gonadal P450aro gene expression. However, in vivo androgen treatment in genetic females does not induce the same pattern of steroid gene expression as in genetic males. These data suggest that exogenous androgens might induce a male differentiation process with P450aro inhibition being one of the steps required. However, this process would not involve endogenously produced 11‐oxygenated androgens. J. Exp. Zool. 290:558–566, 2001. © 2001 Wiley‐Liss, Inc.