bluuebunny/crossref_metadata_2025 huggingface dataset:
Regulation of α‐smooth muscle actin and CRBP‐1 expression by retinoic acid and TGF‐β in cultured fibroblasts
Authors: Xu Guoxiong , Bochaton‐Piallat Marie‐Luce , Andreutti Daniele , Low Robert B. , Gabbiani Giulio , Neuville Pascal
Published: August 2002

We have reported that Cellular Retinol Binding Protein‐1 (CRBP‐1) is expressed de novo during skin wound healing by a proportion of fibroblastic cells which then differentiate into myofibroblasts and express α‐smooth muscle actin. In fibroblasts cultured from different tissues we have shown that α‐smooth muscle actin expression, mainly controlled by Transforming Growth Factor‐β (TGF‐β), is also regulated by retinoic acid and that CRBP‐1, known to be a retinoic acid‐responsive gene, is modulated by TGF‐β. The aim of the present study has been to investigate the relationships between retinoic acid and TGF‐β in regulating the expression of CRBP‐1 and α‐smooth muscle actin in cultured rat subcutaneous tissue fibroblasts. We have observed that the TGF‐β‐induced, but not the retinoic acid‐induced, α‐smooth muscle actin expression is associated with a modulation of endogenous TGF‐β and TGF‐β receptors, suggesting that the action of retinoic acid on α‐smooth muscle actin expression is not mediated by TGF‐β. The expression of CRBP‐1 is regulated at the transcriptional level by TGF‐β and retinoic acid but not synergistically, suggesting a possible common pathway. However, retinoic acid, but not TGF‐β, increases the transcription of a transiently transfected chimeric construct containing the retinoic acid response element of the CRBP‐1 promoter, indicating that TGF‐β does not influence CRBP‐1 through the retinoic acid pathway. Our results indicate that distinct pathways regulate the genes involved in the appearance and evolution of the myofibroblastic cells. The characterization of these pathways will be helpful for the design of drugs influencing wound healing. © 2001 Wiley‐Liss, Inc.
Early molecular changes in irradiated aortic endothelium
Authors: Gajdusek Corinne , Onoda Keisuke , London Susan , Johnson Mark , Morrison Richard , Mayberg Marc
Published: August 2002

Irradiated aortic endothelial cells (EC) exhibit distinct morphological, functional, and physiological responses to ionizing radiation (IR). However, the molecular basis for these responses has not been fully characterized. Cultured bovine and rat aortic endothelial cells were exposed to single fraction doses (0–30 Gy) of gamma radiation. IR caused dose‐dependent DNA strand breaks which were repaired to near baseline levels within 30 min. A dose‐dependent inhibition of cell growth was noted for IR greater than 1 Gy. At doses greater than 2.5 Gy, morphologic changes consistent with apoptosis and loss of cell viability were present beginning 12–16 h after radiation, with subsequent detachment of EC from the cell monolayer. By Western blot analysis, expression of p53, gadd45, p21, and bax protein increased in a time‐and dose‐dependent manner; p53 expression was maximal at 3 h after IR, and gadd45, bax and p21 levels peaked at 6 h. By Reverse Transcriptase Polymerase Chain Reaction (RT‐PCR), levels of p53 mRNA were not significantly increased after IR, whereas gadd45 exhibited time‐ and dose‐dependent increase in mRNA synthesis after IR. Activation of intracellular caspases, manifest by proteolytic poly (ADP‐ribose) polymerase (PARP) and lamin B cleavage, was maximal at 15 h after IR, concident with other indices of EC apoptosis, including oligonucleosomal DNA degradation, TUNEL immunostaining, and morphologic changes. The tripeptide protease inhibitor z‐Val‐Ala‐Asp (zVAD) prevented PARP and lamin cleavage, DNA fragmentation, morphological changes, and cell detachment in irradiated EC. The combined data suggested that gamma radiation induces a dose‐ and time‐dependent sequence of early events in cultured EC with modulate growth arrest, apoptosis, and possibly premature senescence in surviving cells. © 2001 Wiley‐Liss, Inc.
Regulation of angiotensin II‐stimulated osteopontin expression in cardiac microvascular endothelial cells: Role of p42/44 mitogen‐activated protein kinase and reactive oxygen species*
Authors: Xie Zhonglin , Pimental David R. , Lohan Seema , Vasertriger Alla , Pligavko Christina , Colucci Wilson S. , Singh Krishna
Published: August 2002

Using spontaneously hypertensive and aortic banded rats, we have shown that expression of myocardial osteopontin, an extracellular matrix protein, coincides with the development of heart failure and is inhibited by captopril, suggesting a role for angiotensin II (ANG II). This study tested whether ANG II induces osteopontin expression in adult rat ventricular myocytes and cardiac microvascular endothelial cells (CMEC), and if so, whether induction is mediated via activation of mitogen‐activated protein kinases (p42/44 MAPK) and involves reactive oxygen species (ROS). ANG II (1 μM, 16 h) increased osteopontin expression (fold increase 3.3±0.34, n = 12, P < 0.01) in CMEC as measured by northern analysis, but not in ARVM. ANG II stimulated osteopontin expression in CMEC in a time‐ (within 4 h) and concentration‐dependent manner, which was prevented by the AT1 receptor antagonist, losartan. ANG II elicited robust phosphorylation of p42/44 MAPK as measured using phospho‐specific antibodies, and increased superoxide production as measured by cytochrome c reduction and lucigenin chemiluminescence assays. These effects were blocked by diphenylene iodonium (DPI), an inhibitor of the flavoprotein component of NAD(P)H oxidase. PD98059, an inhibitor of p42/44 MAPK pathway, and DPI each inhibited ANG II‐stimulated osteopontin expression. Northern blot analysis showed basal expression of p22phox, a critical component of NADH/NADPH oxidase system, which was increased 40–60% by exposure to ANG II. These results suggest that p42/44 MAPK is a critical component of the ROS‐sensitive signaling pathways activated by ANG II in CMEC and plays a key role in the regulation of osteopontin gene expression. Published 2001 Wiley‐Liss, Inc.
Possible involvement of protein kinases and Smad2 signaling pathways on osteoclast differentiation enhanced by activin A
Authors: Murase Yoshiyuki , Okahashi Nobuo , Koseki Takeyoshi , Itoh Kanami , Udagawa Nobuyuki , Hashimoto Osamu , Sugino Hiromu , Noguchi Toshihiide , Nishihara Tatsuji
Published: August 2002

Bone tissues reportedly contain considerable amounts of activin A and follistatin, an activin A‐binding protein. In the present study, we found that follistatin strongly inhibited osteoclast formation in cocultures of mouse bone marrow cells and primary osteoblasts induced by 1α,25 dihydroxyvitamin D3, prostaglandin E2, and interleukin‐1α. Antibody aganist activin A also inhibited the osteoclast formation. Furthermore, activin A synergistically stimulated osteoclast differentiation mediated by receptor activator NF‐κB ligand (RANKL). RT‐PCR analysis revealed that osteoblasts produced not only activin A but also follistatin. Western blot analysis of a panel of phosphorylated proteins revealed that activin A stimulated the phosphorylation of p44/42 mitogen activated protein (MAP) kinase (ERK1/2) and p38 MAP kinase in macrophage colony‐stimulating factor‐dependent bone marrow macrophages (M‐BMMΦs). In addition, phosphorylation of Smad2 was observed in M‐BMMΦs stimulated with activin A. These findings indicate that the phosphorylation of p44/42 MAP kinase, p38 MAP kinase, and Smad2 is involved in activin A‐enhanced osteoclast differentiation induced by RANKL. Taken together, these results suggest that both activin A and follistatin produced by osteoblasts may play an important role in osteoclast differentiation through MAP kinases and Smad2 signaling pathways. © 2001 Wiley‐Liss, Inc.
Expression of vascular endothelial growth factor receptors in smooth muscle cells
Authors: Ishida Atsushi , Murray Jacqueline , Saito Yuji , Kanthou Chryso , Benzakour Omar , Shibuya Masabumi , Wijelath Errol S.
Published: August 2002

Vascular Endothelial Growth Factor (VEGF) has been typically considered to be an endothelial‐specific growth factor. However, it was recently demonstrated that VEGF can interact with non endothelial cells. In this study, we tested whether vascular smooth muscles cells (VSMCs) can express VEGF receptors, such as flk‐1, flt‐1, and neuropilin (NP)‐1, and respond to VEGF in vitro. In cultured VSMCs, flk‐1 and flt‐1 expression was inversely related to cell density. The expression of flk‐1 was down‐regulated with increasing passage numbers. However, NP‐1 levels were not affected by cell density or passage numbers. Flk‐1, Flt‐1, and NP‐1 protein levels were confirmed by Western Blotting. Although the functional mature form of Flk‐1 protein is expressed at low levels in VSMCs, phosphorylation of Flk‐1 following VEGF165 stimulation was still observed. SMCs migrated significantly in response to VEGF165 and VEGF‐E, whereas Placenta Growth Factor (PlGF) induced migration only at higher concentrations. Since VEGF‐E is a specific activator of flk‐1 while PlGF specifically activates only flt‐1, SMC migration induced by VEGF165 is likely to be mediated primarily through the flk‐1 receptor. VSMCs did not significantly proliferate in response to VEGF165, PlGF, and VEGF‐E. In conclusion, our studies demonstrate the presence of VEGF receptors on VSMCs that are functional. These studies also indicate that in vivo, VEGF may play a role in modulating the response of VSMCs. © 2001 Wiley‐Liss, Inc.
Mechanical control of foaming in stirred‐tank reactors
Authors: Takesono Satoshi , Onodera Masayuki , Ito Akira , Yoshida Masanori , Yamagiwa Kazuaki , Ohkawa Akira
Published: August 2002

The foam‐breaking characteristics of rotating‐disk mechanical foam‐breakers (MFRDs) fitted to stirred‐tank reactors (STRs) containing various foaming liquids were evaluated. The critical disk rotational speed, Nc, required for foam‐breaking and the liquid hold‐up, ϕL, in ascending foam reflected, respectively, the foam‐breaking behaviour of MFRDs and the foaming behaviour of STRs. Empirical equations for the prediction of Nc and ϕL, which can be applied independently of the type, concentration and temperature of foaming liquid, were obtained. The foam‐breaking power, Pkc, of MFRDs was also clarified in relation to the level of ϕL which is related to the difficulty or ease of mechanical foam‐breaking.

© 2001 Society of Chemical Industry
Solar‐assisted photochemical and photocatalytic degradation of phenol
Authors: Yawalkar Archis A , Bhatkhande Dhananjay S , Pangarkar Vishwas G , Beenackers Anthony A C M
Published: August 2002

Photocatalytic (TiO2, air and solar radiation) and photochemical (H2O2 and solar radiation) mineralizations of phenol solutions (up to 500 mg dm−3) in a batch reactor using concentric solar radiation were studied. A compound parabolic reflector as a concentrating reflector was used to obtain concentrated solar radiation in both cases. Considerable enhancement (Five‐fold) in the rate of degradation was obtained when concentrated solar radiation was used instead of plain solar radiation in photocatalytic degradation. The effect of initial phenol concentration, intensity and presence of anions has been studied in both the cases. Low concentrations of intermediates were observed, during the reaction, over the entire range of phenol concentrations studied in the case of photocatalytic degradation using Degussa‐P25 TiO2 as photocatalyst and in the absence of anions; whereas significant quantities of intermediates were observed in the case of the photochemical degradation. The presence of anions generally had a detrimental effect on the mineralization process in both cases. Different anions showed different effects. Total organic carbon (TOC) variations with time were also studied. A rational explanation has been given for the decrease in the rate in the presence of anions.

© 2001 Society of Chemical Industry
Preliminary evaluation of polymeric Fe‐ and Al‐modified clays as adsorbents for heavy metal removal in water treatment
Authors: Cooper Colin , Jiang Jia‐Qian , Ouki Sabeha
Published: August 2002

This paper assesses the potential of modified montmorillonite clays as low‐cost adsorbents/ion‐exchangers for the removal of trace level heavy metals (Cd, Cu, Ni, Pb and Zn) from potable water. Modification of the montmorillonites resulted in the exchange of the interlayer calcium ions for the polymeric species. One unmodified montmorillonite and three polymeric Fe‐ and Al‐modified montmorillonites have been evaluated with respect to their selectivity and uptake performance. All of the clays are selective for Pb and Cu adsorption from aqueous solutions at the mildly acidic pH range in which the experiments were performed (pH 5.5–6). Polymeric iron‐ and polymeric Al/Fe‐modified clays had comparatively great affinities for all the metals studied, whilst the original and polymeric Al modified clays had relatively lower affinities. Only the uptake of Pb and Cu could be correlated with physical properties such as clay surface area. The metal selectivity could be correlated to the type of intercalated polymeric Fe and Al species of the modified clays.

© 2002 Society of Chemical Industry
Effect of pH on microbial hydrogen fermentation
Authors: Lee Young Joon , Miyahara Takashi , Noike Tatsuya
Published: August 2002

The influence of initial pH of the culture medium on hydrogen production was studied using sucrose solution and a mixed microbial flora from a soybean‐meal silo. Hydrogen production was not observed at pH values of 3.0, 11.0 and 12.0 but low production was observed at pH values 5.0 and 5.5. The pH of the experimental mixture decreased rapidly and produced hydrogen gas within 30 h. Methane was not detected at initial pH values between 6.0 and 10.0. The sucrose degradation efficiency increased as the initial pH value increased from 3.0 to 9.0. The maximum sucrose degradation efficiency of 95% was observed at pH 9.0. The maximum specific production yields of hydrogen, VFAs and alcohols were 126.9 cm3 g−1 sucrose (pH of 9.0), 0.7 gCOD g−1 sucrose (pH of 8.0) and 128.7 mgCOD g−1 sucrose (pH of 9.0), respectively. The relationship between the hydrogen ion concentration and the specific hydrogen production rate has been mathematically described. The best kinetic parameters on the specific hydrogen production rate were KOH = 1.0 × 10−7 mol dm−3 and KH = 1.1 × 10−4 mol dm−3 (r2 = 0.86). The maximum specific hydrogen production rate was 37.0 cm3 g−1 VSS h−1.

© 2002 Society of Chemical Industry
Ozone treatment of textile effluents and dyes: effect of applied ozone dose, pH and dye concentration
Authors: Sevimli Mehmet F , Sarikaya Hasan Z
Published: August 2002

The ozonation of wastewater supplied from a treatment plant (Samples A and B) and dye‐bath effluent (Sample C) from a dyeing and finishing mill and acid dye solutions in a semi‐batch reactor has been examined to explore the impact of ozone dose, pH, and initial dye concentration. Results revealed that the apparent rate constants were raised with increases in applied ozone dose and pH, and decreases in initial dye concentration. While the color removal efficiencies of both wastewater Samples A and C for 15 min ozonation at high ozone dosage were 95 and 97%, respectively, these were 81 and 87%, respectively at low ozone dosage. The chemical oxygen demand (COD) and dissolved organic carbon (DOC) removal efficiencies at several ozone dose applications for a 15 min ozonation time were in the ranges of 15–46% and 10–20%, respectively for Sample A and 15–33% and 9–19% respectively for Sample C. Ozone consumption per unit color, COD and DOC removal at any time was found to be almost the same while the applied ozone dose was different. Ozonation could improve the BOD5 (biological oxygen demand) COD ratio of Sample A by 1.6 times with 300 mg dm−3 ozone consumption. Ozonation of acid dyes was a pseudo‐first order reaction with respect to dye. Increases in dye concentration increased specific ozone consumption. Specific ozone consumption for Acid Red 183 (AR‐183) dye solution with a concentration of 50 mg dm−3 rose from 0.32 to 0.72 mg‐O3 per mg dye decomposed as the dye concentration was increased to 500 mg dm−3.

© 2002 Society of Chemical Industry
Sonographic appearances of cervical lymph nodes: Variations by age and sex
Authors: Ying Michael , Ahuja Anil , Brook Fiona
Published: August 2002

Purpose

The purpose of this study was to evaluate the age‐ and sex‐related variations in the numbers and sonographic appearances of normal cervical lymph nodes.

Methods

One hundred thirty‐three healthy subjects (67 men and 66 women) underwent sonographic examinations of the neck, during which 1,299 lymph nodes were detected. The lymph nodes were assessed for their size, shape (short‐to‐long–axis ratio), and border sharpness, as well as for the presence of an echogenic hilum. The subjects were categorized by age (20–29, 30–39, 40–49, and ≥ 50 years) and subcategorized by sex. The differences between the groups in the number of nodes and in their appearance were evaluated.

Results

The mean number of nodes visualized on sonography was significantly higher (p < 0.05) in subjects aged 20–29 and 30–39 years than in subjects aged 40–49 and 50 years or older. The difference in the mean sizes of the cervical nodes between men and women was not statistically significant. The lymph nodes in subjects aged 20–29 and 30–39 years were commonly smaller than those in subjects aged 40–49 and 50 years or older, but the differences were not statistically significant. Neither the shape nor the border sharpness of the cervical lymph nodes varied significantly by age or sex. The incidence of an echogenic hilum within the lymph nodes increased significantly with age in both sexes (p < 0.05).

Conclusions

This study provides information about the sonographic appearances of and variations between normal cervical lymph nodes. The presence of an increased number of cervical lymph nodes and the absence of an echogenic hilum within the nodes may help to identify an abnormality more in older patients than in younger patients. © 2002 John Wiley & Sons, Inc. J Clin Ultrasound 30:1–11, 2002.
Malignant non‐Hodgkin's lymphoma mimicking a benign parotid tumor: Sonographic findings
Authors: Eichhorn Klaus W. G. , Arapakis Iakovos , Ridder Gerd Jürgen
Published: August 2002

We report the case of an extranodal non‐Hodgkin's lymphoma mimicking a benign tumor in the left parotid gland of a 71‐year‐old woman. The clinical presentation of the painless, mobile mass was suggestive of a benign parotid tumor such as an adenoma. The intraglandular tumor appeared sonographically as a well‐circumscribed, hypoechoic, homogeneous, lobulated mass with mild distal sound enhancement. Power Doppler sonography showed marked intratumoral vascularization. The tumor was resected by lateral lobectomy of the parotid gland and was found histopathologically to be a diffuse large B‐cell lymphoma. © 2002 John Wiley & Sons, Inc. J Clin Ultrasound 30:42–44, 2002.
Two‐dimensional and three‐dimensional sonography of conjoined twins
Authors: Bonilla‐Musoles Fernando , Machado Luiz E. , Osborne Newton G. , Blanes Javier , Bonilla Francisco , Raga Francisco , Machado Fernanda
Published: August 2002

Purpose

The aim of this study was to evaluate and compare the diagnostic capabilities of 2‐dimensional (2D) and 3‐dimensional (3D) sonography for the study of conjoined twins.

Methods

Four pregnant women with an initial 2D sonographic diagnosis of conjoined twins were examined with color Doppler sonography, 3D multiplanar sonography, and orthogonal plane imaging and 3D surface rendering.

Results

All 4 cases of conjoined twins were initially diagnosed with either transvaginal or transabdominal 2D sonography. 3D sonography afforded more realistic views and demonstrated more clearly the linking areas and surface anomalies, but 2D and color Doppler sonography provided more definitive and specific information about shared organs.

Conclusions

Although 2D sonography is the primary modality for diagnosing and evaluating conjoined twins, color Doppler and 3D sonography can sometimes provide additional information that assists in the clinical management of these twins. 3D sonography also provides images that are easier for parents to understand, which can help them with decision making. © 2002 John Wiley & Sons, Inc. J Clin Ultrasound 30:68–75, 2002; DOI 10.1002/jcu.10035
Role of the supraoptic nucleus in regulation of parturition and milk ejection revisited
Authors: Higuchi Takashi , Okere Chuma O.
Published: August 2002

This review will focus on the activity of oxytocin neurons in the supraoptic nucleus (SON) and some factors that regulate their function during parturition and milk ejection in the rat. The level of oxytocin increases in the blood during parturition following a regression of the corpus luteum. The increase in oxytocin secretion is presumably a consequence of releasing the oxytocin neurons from restraining inhibitory influences of endogenous opioids‐, nitric oxide‐, and GABA‐containing neurons following declining blood levels of progesterone on the one hand and increasing levels of estrogen on the other during late pregnancy. However, the principal stimulus for the increased oxytocin release is believed to originate, at least in part, from mechanical stimulation to the uterine cervix by fetuses near term, the resultant uterine contractile activity, and the fetal expulsion reflex. Hence, the contractile activity of the uterus acts through positive feedback mechanisms during parturition to stimulate oxytocin neurons as well, and this further increases the secretion of oxytocin. During suckling in lactating rats, somatosensory stimuli from the pups induce intermittent synchronized burst firing of oxytocin neurons, resulting in pulsatile increases in blood oxytocin concentrations to cause milk ejection. The oxytocin neurons appear to have an intrinsic capability to fire in a bursting fashion as determined by observation of this phenomenon in brain slice or tissue culture preparations. The release of oxytocin within the microenvironment of the SON and paraventricular nucleus coupled with morphological reorganization in these nuclei play important roles in the bursting activity of each oxytocin neuron and synchronization in vivo. However, the mechanism responsible for the synchronization of electrical activity in oxytocin neurons in the four discrete hypothalamic nuclei remains an interesting unanswered question. Microsc. Res. Tech. 56:113–121, 2002. © 2002 Wiley‐Liss, Inc.
Expression and plasticity of glutamate receptors in the supraoptic nucleus of the hypothalamus
Authors: Pak C. Wook , Currás‐Collazo Margarita C.
Published: August 2002

Magnocellular neuroendocrine cells (MNCs) of the supraoptic nucleus of the hypothalamus (SON) produce and release the hormones vasopressin (VP) and oxytocin (OT) in response to a variety of stimuli to regulate body water and salt, parturition and lactation. Hormone release is influenced by the pattern of neuronal firing of these MNCs, which, in turn, is governed by intrinsic conductances and synaptic inputs, including those mediated by the neurotransmitter glutamate. Functional and molecular evidence has confirmed the expression of AMPA‐, NMDA‐, and metabotropic‐type glutamate receptors in the SON, that together may orchestrate the effects of glutamatergic transmission on neuroendocrine function. However, the specific roles of the different subtypes of glutamate receptors is not yet clear. As with other central neurons, the subunit composition of glutamate receptors on MNCs will likely determine their properties and may potentially help define the differential properties of VP‐ and OT‐producing MNCs. Possible functions of glutamate receptors on SON MNCs include altering excitatory synaptic transmission of osmotic information, neuronal firing, hormone production and release, and calcium signaling. Of interest are the anatomical, molecular, and functional changes at glutamatergic synapses in the SON that occur in response to pertinent physiological stimuli or development. These types of plasticity may include changes in glutamatergic synaptic density, glutamate receptor levels, or glutamate receptor subunit expression, all of which can affect the efficiency of synaptic transmission. Microsc. Res. Tech. 56:92–100, 2002. © 2002 Wiley‐Liss, Inc.
Vanadocytes, cells hold the key to resolving the highly selective accumulation and reduction of vanadium in ascidians
Authors: Michibata Hitoshi , Uyama Taro , Ueki Tatsuya , Kanamori Kan
Published: August 2002

Since Henze discovered vanadium in the blood (or coelomic) cells of an ascidian in 1911, this unusual phenomenon has attracted the interest of many investigators. The highest concentration of vanadium (350 mM) in the blood cells of Ascidia gemmata, which belongs to the suborder Phlebobranchia, is 107 times higher than that in seawater. Of the approximately 10 types of blood cells, a combination of cell fractionation and neutron‐activation analysis revealed that the signet ring cells were the true vanadocytes. In the vanadocytes, 97.6% of the vanadium is in the +3 oxidation state (III). The extremely low pH of 1.9 found in vanadocytes suggests that protons, concentrated by an H+‐ATPase, might be linked to the accumulation of vanadium energetically. The antigen recognized by a monoclonal antibody, S4D5, prepared to identify vanadocytes, was determined to be 6‐PGDH in the pentose phosphate pathway. NADPH produced in the pentose phosphate pathway in vanadocytes is thought to participate in the reduction of vanadium(V) to vanadium(IV). During embryogenesis, a vanadocyte‐specific antigen first appears in the body wall at the same time that significant accumulations of vanadium become apparent. Three different vanadium‐associated proteins (VAPs) were extracted from the blood cells of vanadium‐rich ascidians. These are 12.5, 15, and 16 kDa in size and are associated with vanadium in an approximate ratio of 1:16. The cDNA encoding the 12.5 and 15 kDa VAPs was isolated and the proteins encoded were found to be novel. Further biochemical and biophysical characterization of the VAPs is in progress. Microsc. Res. Tech. 56:421–434, 2002. © 2002 Wiley‐Liss, Inc.
Cyclic GMP signaling in podocytes
Authors: Lewko Barbara , Stepinski Jan
Published: August 2002

Natriuretic peptides (NP), together with nitric oxide (NO) are powerful relaxing factors acting via a common second messenger, cyclic GMP (cGMP). Together with other vasoactive modulators, these vasorelaxing factors play an essential role in regulating the function of kidney glomeruli. The presence of NP receptors in podocytes has been well documented. Recently, also mRNA for soluble guanylate cyclase, the NO receptor, has been shown in these cells. Stimulation of podocytes with atrial natriuretic peptide (ANP), C‐type natriuretic peptide (CNP), and NO donors results in considerable upregulation of cellular cGMP synthesis. The podocyte foot processes contain a highly organized network of microfilaments adhering to the glomerular basement membrane (GBM). Changes in podocyte cytoskeleton accompanied by detachment of the cells from the GBM are closely associated with many glomerulopathies. The contractile apparatus in the podocyte foot processes seems to be an obvious target for the cyclic GMP signaling cascade. However, little is known about implications of the cGMP synthesis in these cells. We briefly review the current art regarding generation and modulation of cyclic GMP levels in podocytes. We discuss also the possible targets for this secondary messenger as well as its functional role in podocytes. Microsc. Res. Tech. 57:232–235, 2002. © 2002 Wiley‐Liss, Inc.
Microglial interaction with β‐amyloid: Implications for the pathogenesis of Alzheimer's disease
Authors: Bamberger Maria E. , Landreth Gary E.
Published: August 2002

The etiology of Alzheimer's disease (AD) involves a significant inflammatory component as evidenced by the presence of elevated levels of a diverse range of proinflammatory molecules in the AD brain. These inflammatory molecules are produced principally by activated microglia, which are found to be clustered within and adjacent to the senile plaque. Moreover, long‐term treatment of patients with non‐steroidal anti‐inflammatory drugs has been shown to reduce risk and incidence of AD and delay disease progression. The microglia respond to beta‐amyloid (Aβ) deposition in the brain through the interaction of fibrillar forms of amyloid with cell surface receptors, leading to the activation of intracellular signal transduction cascades. The activation of multiple independent signaling pathways ultimately leads to the induction of proinflammatory gene expression and production of reactive oxygen and nitrogen species. These microglial inflammatory products act in concert to produce neuronal toxicity and death. Therapeutic approaches focused on inhibition of the microglial‐mediated local inflammatory response in the AD brain offer new opportunities to intervene in the disease. Microsc. Res. Tech. 54:59–70, 2001. © 2001 Wiley‐Liss, Inc.
Peptides in frog brain areas processing visual information
Authors: Lázár Gyula
Published: August 2002

Vision is the most important sensory modality to anurans and a great deal of work in terms of hodological, physiological, and behavioral studies has been devoted to the visual system. The aim of this account is to survey data about the distribution of peptides in primary (lateral geniculate complex, pretectum, tectum) and secondary (striatum, anterodorsal and anteroventral tegmental nuclei, isthmic nucleus) visual relay centers. The emphasis is on general traits but interspecies variations are also noted. The smallest amount of peptide‐containing neuronal elements was found in the lateral geniculate complex, where primarily nerve fibers showed immunostaining. All peptides found in the lateral geniculate complex, except two, occurred in the pretectum together with four other peptides. A large number of neurons showing intense neuropeptide thyrosine‐like immunoreactivity was characteristic here. The mesencephalic tectum was the richest in peptide‐like immunoreactive neuronal elements. Almost all peptides investigated were present mainly in fibers, but 9 peptides were found also in cells. The immunoreactive fibers show a complicated overlapping laminar arrangement. Cholecystokinin octapeptide, enkephalins, neuropeptide tyrosine, and substance P (not discussed here) gave the most prominent immunoreactivity. Several peptides also occur in the tectum of fishes, reptiles, birds, and mammals. Peptides in various combinations were found in the striatum, the anterodorsal‐ and anteroventral tegmental nucleus, and the isthmic nucleus that receive projections from the primary visual centers. The functional significance of peptides in visual information processing is not known. The only exception is neuropeptide tyrosine, which was found to be inhibitory on retinotectal synapses. Microsc. Res. Tech. 54:201–219, 2001. © 2001 Wiley‐Liss, Inc.
Sex differences in songbirds 25 years later: What have we learned and where do we go?
Authors: Ball Gregory F. , Macdougall‐Shackleton Scott A.
Published: August 2002

About 25 years ago, Nottebohm and Arnold reported that there are profound male‐biased sex differences in volume in selected nuclei in telencephalic portions of the song control system. This review focuses on issues related to the cellular bases of these sex differences in volume and comparative studies that might elucidate the function of this variation between the sexes. Studies utilizing a variety of neurohistological methods in several different species to define the boundaries of two key telencephalic song nuclei HVc and the robust nucleus of the archistriatum (RA) all tend to find a sex difference in volume in agreement with Nissl‐defined boundaries. Sex differences in volume in nuclei such as HVc and RA are associated with differences in cell size and cell number. Other attributes of the phenotype of cells in these nuclei are also different in males and females such as the number of cells expressing androgen receptors. Comparative studies have been employed to understand the function of these sex differences in the brain. In some songbird species, females sing rarely or not at all, and the brain nuclei that control song are many times larger volume in males than females. In other species, males and females sing approximately equally, and the brain nuclei that control song are approximately equal between the sexes. Recently, statistical methods have been employed to control for phylogenetic effects while comparing the co‐evolution of traits. This analysis indicates that the evolution of sex differences in song has co‐evolved with the evolution of sex differences in singing behavior in songbird species. Future studies should focus on the function of the smaller song control nuclei of females and investigate the role these nuclei might play in perception as well as in production. Microsc. Res. Tech. 54:327–334, 2001. © 2001 Wiley‐Liss, Inc.
Synthesis, distribution, and levels of an egg lipoprotein from the apple snail Pomacea canaliculata (Mollusca: Gastropoda)
Authors: Dreon M. , Lavarias S. , Garin C.F. , Heras H. , Pollero R.J.
Published: August 2002

The site of synthesis of mollusc lipoproteins is hitherto unknown and was investigated for perivitellin 2 (PV2), an egg lipoprotein found in the freshwater snail Pomacea canaliculata. Tissues (albumen gland, gonad–digestive gland complex, and muscle) from vitellogenic females were incubated in vitro with 14C‐leucine at 25°C for 12 hr. At the end of incubation, soluble proteins from tissue homogenates and medium were analyzed for de novo protein synthesis by electrophoresis and HPLC, and radiolabeled proteins were quantified by liquid scintillation. Two albumen gland radiolabeled proteins (67 and 31 kDa) co‐migrated with the subunits of PV2, and they represented 6.0% of the total labeled protein in that tissue. Western blot analysis confirmed the presence of PV2 only in the albumen gland. In vivo experiments where adult females were injected with 3H‐leucine revealed that PV2 was not present in hemolymph. ELISA analysis in all tissues of the snail confirmed the PV2 presence only in the albumen gland and developing eggs with levels of 26 and 98 mg/g protein, respectively. Therefore, the albumen gland is the only site for PV2 synthesis, and no extra‐gland synthesis, circulation, or accumulation could be found. PV2 subunits were further characterized analyzing N‐terminal sequences which showed no homology with other proteins. J. Exp. Zool. 292:323–330, 2002. © 2002 Wiley‐Liss, Inc.
Acid–base regulation in fishes: cellular and molecular mechanisms
Authors: Claiborne James B. , Edwards Susan L. , Morrison‐Shetlar Alison I.
Published: August 2002

The mechanisms underlying acid–base transfers across the branchial epithelium of fishes have been studied for more than 70 years. These animals are able to compensate for changes to internal pH following a wide range of acid–base challenges, and the gill epithelium is the primary site of acid–base transfers to the water. This paper reviews recent molecular, immunohistochemical, and functional studies that have begun to define the protein transporters involved in the acid–base relevant ion transfers. Both Na+/H+ exchange (NHE) and vacuolar‐type H+‐ATPase transport H+ from the fish to the environment. While NHEs have been thought to carry out this function mainly in seawater‐adapted animals, these proteins have now been localized to mitochondrial‐rich cells in the gill epithelium of both fresh and saltwater‐adapted fishes. NHEs have been found in the gill epithelium of elasmobranchs, teleosts, and an agnathan. In several species, apical isoforms (NHE2 and NHE3) appear to be up‐regulated following acidosis. In freshwater teleosts, H+‐ATPase drives H+ excretion and is indirectly coupled to Na+ uptake (via Na+ channels). It has been localized to respiratory pavement cells and chloride cells of the gill epithelium. In the marine elasmobranch, both branchial NHE and H+‐ATPase have been identified, suggesting that a combination of these mechanisms may be utilized by marine elasmobranchs for acid–base regulation. An apically located Cl−/HCO3− anion exchanger in chloride cells may be responsible for base excretion in fresh and seawater‐adapted fishes. While only a few species have been examined to date, new molecular approaches applied to a wider range of fishes will continue to improve our understanding of the roles of the various gill membrane transport processes in acid–base balance. © 2002 Wiley‐Liss, Inc.
Negative test for cloacal drinking in a semi‐aquatic turtle (Trachemys scripta), with comments on the functions of cloacal bursae
Authors: Peterson Charles C. , Greenshields David
Published: August 2002

Many aquatic turtles possess paired evaginations of the cloaca called cloacal bursae. Despite more than two centuries of study, little consensus exists as to the function(s) of these organs. We tested a recent suggestion that bursae could function in water uptake (“cloacal drinking”). Turtles (Trachemys scripta) were dehydrated (68–86% of maximum body mass) and given the opportunity to drink orally or cloacally. Dehydration caused increases in hematocrit and osmolality of extracellular fluid (ECF), but only after loss of 10–12% of maximum body mass, suggesting that turtles osmoregulated by reabsorbing water from the urinary bladder. Turtles drank eagerly when they could submerge their heads, and drinking was accompanied by an increase in body mass and a decrease in ECF osmolality. However, dehydrated turtles with tail and anus submerged showed no changes in mass or osmolality, suggesting that water absorption is not a significant function of the cloacal bursae in this species. Evidence for other putative functions is reviewed, leading to a pluralistic view: in cryptodires, bursae apparently function primarily in buoyancy control and secondarily in ion transport and nesting, but several pleurodires have been shown recently to use them in aquatic respiration.J. Exp. Zool. 290:247–254, 2001. © 2001 Wiley‐Liss, Inc.
Contribution of domestic animals to the identification of new genes involved in sex determination
Authors: Pailhoux Eric , Vigier Bernard , Vaiman Daniel , Schibler Laurent , Vaiman Anne , Cribiu Edmond , Nezer Carine , Georges Michel , Sundström Jari , Pelliniemi Lauri J. , Fellous Marc , Cotinot Corinne
Published: August 2002

Among farm animals, two species present an intersex condition at a relatively high frequency: pig and goat. Both are known to contain XX sex‐reversed individuals which are genetically female but with a true hermaphrodite or male phenotype. It has been clearly demonstrated that the SRY gene is not involved in these phenotypes. Consequently, autosomal or X‐linked mutations in the sex‐determining pathway may explain these sex‐reversed phenotypes. A mutation referred to as “polled” has been characterized in goats by the suppression of horn formation and abnormal sexual differentiation. The Polled Intersex Syndrome locus (PIS) was initially located in the distal region of goat chromosome 1. The homologous human region has been precisely identified as an HSA 3q23 DNA segment containing the Blepharophimosis Ptosis Epicanthus locus (BPES), a syndrome combining Premature Ovarian Failure (POF) and an excess of epidermis of the eyelids.

In order to isolate genes involved in pig intersexuality, a similar genetic approach was attempted in pigs using genome scanning of resource families. Genetic analyses suggest that pig intersexuality is controlled multigenically. Parallel to this work, gonads of fetal intersex animals have been studied during development by light and electron microscopy. The development of testicular tissue and reduction of germ cell number by apoptosis, which simultaneously occurs as soon as 50 days post coïtum, also suggests that several separate genes could be involved in pig intersexuality. J. Exp. Zool. 290:700–708, 2001. © 2001 Wiley‐Liss, Inc.
A molecular phylogenetic study of ecological diversification in the Australian lizard genus Ctenophorus
Authors: Melville Jane , Schulte James A. , Larson Allan
Published: August 2002

We present phylogenetic analyses of the lizard genus Ctenophorus using 1,639 aligned positions of mitochondrial DNA sequences containing 799 parsimony‐informative characters for samples of 22 species of Ctenophorus and 12 additional Australian agamid genera. Sequences from three protein‐coding genes (ND1, ND2, and COI) and eight intervening tRNA genes are examined using both parsimony and maximum‐likelihood analyses. Species of Ctenophorus form a monophyletic group with Rankinia adelaidensis, which we suggest placing in Ctenophorus. Ecological differentiation among species of Ctenophorus is most evident in the kinds of habitats used for shelter. Phylogenetic analyses suggest that the ancestral condition is to use burrows for shelter, and that habits of sheltering in rocks and shrubs/hummock grasses represent separately derived conditions. Ctenophorus appears to have undergone extensive cladogenesis approximately 10–12 million years ago, with all three major ecological modes being established at that time. J. Exp. Zool. (Mol. Dev. Evol.) 291:339–353, 2001. © 2001 Wiley‐Liss, Inc.
K4−‐factor in a graph
Authors: Kawarabayashi Ken‐ichi
Published: August 2002

Let G be a graph of order 4k and let δ(G) denote the minimum degree of G. Let F be a given connected graph. Suppose that |V(G)| is a multiple of |V(F)|. A spanning subgraph of G is called an F‐factor if its components are all isomorphic to F.

In this paper, we prove that if δ(G)≥5/2k, then G contains a K4−‐factor (K4− is the graph obtained from K4 by deleting just one edge). The condition on the minimum degree is best possible in a sense. In addition, the proof can be made algorithmic. © 2002 John Wiley & Sons, Inc. J Graph Theory 39: 111–128, 2002
Brace generation
Authors: McCuaig William
Published: August 2002

A brace is a connected bipartite graph with a perfect matching and at least six vertices such that for every pair of nonadjacent edges, there is a perfect matching containing the edges. We give a method for generating all braces. © 2001 John Wiley & Sons, Inc. J Graph Theory 38: 124–169, 2001
Privatization in Turkey: Implementation, politics of privatization and performance results
Authors: Karataş Cevat
Published: August 2002

The paper provides a comprehensive survey of privatization transastions in Turkey which took place between 1986 and 2000. The objectives of the privatization programme and privatized and nominated SOEs are discussed. The breakdown of total proceeds by sales methods and scope of the privatization programme by economic sectors are examined. The saleability of relatively large public enterprises is reviewed and utilization of privatization proceeds during and after privatization process is critically appraised. In addition, an attempt is made to discuss the politics of privatization by referring to key political and economic factors which have influenced implementation of the privatization programme. Following a short review of the economic environment and macroeconomic indicators in Turkey, focus is also placed on the research results that are available on the performance of public, private and privatized SOEs, particularly in the cement sector. In the final section, some key issues relevant to Turkish privatization are accentuated and some conclusion are drawn. © 2001 John Wiley & Sons, Ltd.
Resource allocation and priority setting of HIV/AIDS interventions: addressing the generalized epidemic in sub‐Saharan Africa
Authors: Kumaranayake Lilani , Watts Charlotte
Published: August 2002

The endemic nature of HIV/AIDS in Africa has led to substantial activity to intensify action in SSA over the past two years. There has been both a reallocation of resources towards HIV/AIDS and wide scale efforts at mobilizing additional resources to scale up HIV/AIDS prevention and care interventions. Despite efforts to rapidly mobilize resources, priority‐setting among the various interventions remains a central issue, with broad debates about how resources should be allocated, and particular concern about treatment and the availability of drugs. In this paper, we discuss the range of interventions which are commonly implemented for HIV/AIDS and the debate around priority‐setting, in settings where the HIV epidemic is centralised. Copyright © 2001 John Wiley & Sons, Ltd.
A livelihood from the forest: gendered visions of social, economic and environmental change in Southern Cameroon
Authors: Brown Katrina , Lapuyade Sandrine
Published: August 2002

This paper explores divergent perceptions and experiences of social, economic and environmental change of villagers in Southern Cameroon arguing that the economic crisis has impacted very differently on men and women within the same community and within households. The analysis highlights shifts in cropping patterns towards increased food crops, especially cassava and plantain, for cash. Sources of livelihood for men have diversified in the face of economic crisis, whereas women have reduced room to manoeuvre. This results in women becoming increasingly dependent on utilizing non‐timber forest products for cash in order to meet their livelihood needs. However pressures on forest are increasing for a number of reasons and access to land and trees is becoming constrained, so future benefits from forest products will be contingent on clear, well defined and enforced community property rights. Copyright © 2001 John Wiley & Sons, Ltd.
Growth and institutions
Authors: Fedderke Johannes
Published: August 2002

Alternative conceptions of the link between social and political institutions and economic growth are explored theoretically and empirically. A number of plausible hypotheses found in the literature are found to have distinct implications for social steady state, including the possibility of low income steady state institutional traps. Empirical evidence suggests considerable heterogeneity between countries in the nature of the link between institutions and economic activity, throwing doubt on the validity of standard cross‐sectional growth equations. The application of cointegration techniques of analysis identifies a number of countries that may prove fruitful as the object of more detailed clinical analysis. Copyright © 2001 John Wiley & Sons, Ltd.
One‐step purification of glucoamylase by affinity precipitation with alginate
Authors: Teotia S. , Lata R. , Khare S. K. , Gupta M. N.
Published: August 2002

It was found that alginate binds to glucoamylase, presumably through the recognition of starch binding domain of the latter. The present work exploits this for purification of glucoamylases from commercial preparation of Aspergillus niger and crude culture filtrate of Bacillus amyloliquefaciens by affinity precipitation technique in a single‐step protocol. Glucoamylase is selectively precipitated using alginate as macroaffinity ligand and later eluted with 1.0 M maltose. In the case of A. niger, 81% activity is recovered with 28‐fold purification. The purified glucoamylase gave a single band on SDS–PAGE corresponding to 78 kDa molecular weight. The developed affinity precipitation process also works efficiently for purification of Bacillus amyloliquefaciens glucoamylase from its crude culture filtrate, giving 78% recovery with 38‐fold purification. The purified preparation showed a major band corresponding to 62 kDa and a faint band about 50 kDa on SDS–PAGE. The latter corresponds to the molecular weight for α‐amylase of Bacillus amyloliquefaciens. Copyright © 2001 John Wiley & Sons, Ltd.