bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization of exfoliated cells and tissues from human endocervix and ectocervix by FTIR and ATR/FTIR Spectroscopy
Authors: Wong Patrick T. T. , Lacelle Suzanne , Fung Michael Fung Kee , Senterman Mary , Mikhael Nadia Z. 
Published: May 2005

AbstractThe transmission infrared spectra of exfoliated endocervical mucin‐producing columnar epithelial cells and the attenuated total reflectance (ATR) infrared spectra of the single‐columnar cell layer on the endocervical tissues have been measured and compared with the corresponding infrared spectra of the ectocervical squamous cells and squamous epithelium. The infrared spectra of the exfoliated cervical cells obtained from the present work are comparable with those directly measured from the epithelia on the cervical tissues by ATR technique. The transmission infrared spectra of endocervical columnar epithelial tissue containing some components of the underlying connective tissue have also been measured and compared with the ATR/FTIR (Fourier‐transform infrared) spectra of the endocervical columnar epithelial tissue. The effects of the contaminated connective tissue on the infrared spectra of the endocervical columnar epithelial tissue have demonstrated that ATR/FTIR is a more desirable method than the transmission method to obtain meaningful and good‐quality infrared spectra of tissue samples, especially samples consisting of thin layers of different types of tissues. Substantial differences in the infrared spectra between the columnar cells and squamous cells on the endocervical and ectocervical tissues, respectively, were evident. The strong glycogen bands in the infrared spectrum of the ectocervical squamous cells are absent in the spectrum of the endocervical columnar cells. This spectral change is similar to that observed in malignant squamous cells. Therefore, if the decrease in the intensity of the glycogen bands is used as the only criterion for the determination of cellular abnormalities in the cervix, the presence of a large number of normal endocervical columnar cells in the cervical specimen would lead to a false result. Consequently, in addition to the glycogen bands, other features in the infrared spectra should be considered for the evaluation of abnormalities in exfoliated cervical epithelial cells. In order to identify the spectral features that are unique to endocervical columnar cells, the infrared spectra of an aqueous solution of glycogen, the mucus from the endocervix, and the connective tissues from both the endocervix and the ectocervix have also been measured and analyzed. © 1995 John Wiley & Sons, Inc.
Context and its significance in identifying ‘what works’ in child protection
Authors: Barton Adrian , Welbourne Penelope 
Published: May 2005

AbstractThe repetitive nature of the underlying problems with child protection systems identified by many inquiries into child deaths suggests that the ability to transpose successful strategies from one area to another may be contingent on more than a ‘technical’ approach to best practice. Current policy responses to failing child protection systems are arguably based on an assumption that practices that work in one area may be applied in other areas without reference to the existing base for practice. Drawing on our own experiences in the field, we attempt to explore some methodological issues relevant to the evaluation of service provision and the dissemination of effective practice in interagency working. Copyright © 2005 John Wiley & Sons, Ltd.
Cellular utilization of cytosolic NADPH in kidney and liver cells from rats fed a normal or a vitamin D‐deficient diet
Authors: Bachelet Marie , Bader Cyrille , Merlot Anne‐Marie , Laborde Kathleen , Snarska Joanna , Ulmann Andréa 
Published: May 2005

AbstractThe amount of reducing equivalents from NADPH generated by glucose 6‐phosphate dehydrogenase activity (G6PD) used in mixed function oxidation (pathway I) or in reductive biosynthesis (pathway II) has been determined by cytochemical methods and microdensitometry in cells from the pars recta (PR) and distal convoluted tubule (DCT) of the kidney and from centrilobular (CL) and periportal (PP) hepatocytes from rats fed a normal or a vitamin D‐deficient diet. In the kidney, pathway I activity was similar to that of pathway II in PR, whereas in DCT pathway II was markedly predominant. Feeding a vitamin D‐deficient diet resulted in an increase in the total amount of reducing equivalents in PR and DCT. This increase was due to a rise in pathway I activity in the PR, whereas in the DCT the increase resulted from a stimulation of pathway II activity. Pathway I activity in PR was inversely correlated with plasma calcium, and was significantly decreased when calcium (1 mM) was added in vitro. In the liver the total amount of reducing equivalents generated by G6PD and both hydrogen pathways, was higher in CL than in PP hepatocytes. In CL cells, a vitamin D‐deficient diet induced a significant increase in both NADPH pathways. Furthermore, in these cells pathway I activity was inversely related to plasma calcium and was significantly lowered when 1 mM calcium was added in vitro. It is concluded that vitamin D status and calcium influence the production and utilization of cytosolic reducing equivalents both in kidney and liver.
Activation of carboxylesterases in root cortical parenchymal cells of Pisum sativum during xylem induction in vitro
Authors: Gahan P. B. , Rana M. A. , Phillips R. 
Published: May 2005

AbstractA quantitative cytochemical study of naphthol AS‐D esterase activity in explants from roots of Pisum sativum grown on basal medium for 3 or 6 days showed similar levels of activity to those seen in sections of cortex and stele from intact roots of similar ages. Explants grown in the presence of auxins or cytokinin alone showed a threefold or twofold increase in cortical parenchymal activity, respectively. On adding both hormones to initiate xylem element formation, there was also a threefold increase in activity in the cortex. In all three cases, the stimulated activity was totally inhibited by either 10−4 M diisopropylfluorophosphate (DFP) or 10−4 M diethyl p‐nitrophenyl‐phosphate (E600), indicating carboxylesterase activity. The low level of activity normally present in cortical cells was inhibitor resistant, so indicating acetylesterase activity. Thus, auxins and cytokinins appear to activate mainly similar carboxylesterases during the initiation of xylem elements from cortical parenchyma cells.
Comparison of androgen biosynthesis in isolated Leydig cells from rat and mouse testis: Incubation and superfusion studies
Authors: Kühn‐Velten N. , Schumacher H. , Wolff J. , Staib W. 
Published: May 2005

AbstractProduction of testosterone by highly purified Leydig cells prepared from rat and mouse testes is compared. Testosterone formation is improved to a higher degree in rat (2.7‐fold) than in mouse (1.7‐fold) cells by callagenase treatment of the testis compared with mechanical isolation. Mouse Leydig cells respond to exogenous stimuli (chorigonadotropin, dibutyryl cyclic AMP) with 2.4‐fold higher testosterone secretion than rat cells. A 1.7‐fold increased conversion of androgen precursors to testosterone by mouse compared with rat Leydig cells is demonstrated in static incubations as well as in steady‐state superfusion experiments and can be derived from enhanced androstenedione reduction and a less inhibitory effect of progesterone on this process is mouse Leydig cells.
Use of microscopic interferometry for measuring changes in water content of small samples of tissue
Authors: Darracott‐C̄anković S. , Braimbridge M. V. , Kyösola K. , Bitensky L. , Chayen J. 
Published: May 2005

AbstractOedema following periods of ischaemic arrest and subsequent reperfusion has been shown experimentally and clinically to affect the functional state of the heart. Tissue water content has been measured in myocardial sections by microscopic interferometry and densitometry, and the results correlated with those obtained by wet and dry weight analysis (r = 0.87; p < 0.001). Microscopic interferometry also revealed the distribution of the water in the tissue. Experimentally induced ischaemic arrest in isolated rat hearts resulted in predominantly intra‐fibrillar oedema, whilst subsequent reperfusion resulted in interfibrillar oedema. Microscopic interferometry facilitates accurate measurement of water content in tissue samples as small as 2 mg wet weight and shows (as conventional wet/dry weight analysis cannot) the distribution of the water in the tissue.
Integrity of glycoprotein complex sugars is required for homing but not for several other membrane‐mediated functions
Authors: Hooghe Robert J. , Plaetse Frank Vander , de Saint‐Georges Louis , Janowski Michel , Schaaf‐Lafontaine Nicole , Hooghe‐Peters Elisabeth L. , Dorling Peter 
Published: May 2005

AbstractIn order to correlate the biochemistry of cell surface carbohydrates with cell function, we have treated cells with swainsonine and followed the biochemical and functional modifications induced by this compound. After treatment with swainsonine, surface glycoproteins had a lower apparent molecular weight and a higher isoelectric point. This is compatible with the replacement of complex carbohydrates by hybrid or high‐mannose carbohydrates. Several functional tests were unaffected. However, swainsonine‐treated cells displayed an altered pattern of in vivo homing, suggesting that carbohydrates play a role in this process.
Effect of methylglyoxal on tumour microtubular protein
Authors: Miglietta A. , Bonelli G. , Vironda N. , Gabriel L. 
Published: May 2005

AbstractMethylglyoxal inhibits cell division, exerting an antiproliferative action on tumour cells. Supernatants from ascites hepatoma cell homogenate, previously incubated with the aldehyde, showed a decrease in colchicine binding activity dependent on methylglyoxal concentration. In contrast, in vivo treatment of tumour‐bearing rats apparently did not cause a significant impairment of microtubular protein, suggesting that the aldehyde interaction with microtubules cannot be considered responsible for its carcinostatic action.
Fibronectin assays and their clinical application: A review
Authors: Boughton B. J. 
Published: May 2005

AbstractCold insoluble globulin (fibronectin) was discovered 30 years ago but recently there has been a remarkable growth of knowledge concerning its interaction with the cell cytoskeleton and its role in cell‐cell and cell‐matrix adhesion. The protein is also a major plasma opsonin with a role in regulating fixed macrophage activity and it is this area in which clinical applications are now beginning to develop. Methods are discussed for measuring the concentration of the protein and its opsonic function in vitro, and for the evaluation of fixed macrophage function in vivo. Also discussed are the metabolism of the protein, the implications of opsonin depletion in patients with serious injury or infection and the attempts to reverse this with plasma protein replacement therapy.
Increased myosin orientation during muscle contraction: A measure of cardiac contractility
Authors: Chayen J. , Bitensky Lucille , Braimbridge M. V. , Darracott‐Cankovic Sally 
Published: May 2005

AbstractMyosin form birefringence has been studied in cryostat sections of left ventricular myocardium from the dog and human. The muscle in such sections has been shown to demonstrate the sliding filament phenomenon. The sarcomere length of canine myocardium agreed with that found in comparable electron micrographs. Unexpectedly, it was found that glycerol, normally used as an inert and optically ideal mountant, caused profound change in myosin birefringence. This apparently invalidates results obtained with this mountant.The absolute birefringence found in these sections, whether mounted in glycerol or in an ATP‐calcium buffer, corresponded to values found by other workers with skeletal muscle and isolated myosin. However, the birefringent properties (optical path difference: o.p.d.) of well functioning muscle was found to be low, the o.p.d. increasing when exposed to ATP and calcium. Poorly functioning muscle could be distinguished from well functioning muscle on the basis of its higher ‘in air’ o.p.d. This difference correlated well with physiological assessments of myocardial function or with clinical assessments of cardiac failure. Evidence is presented indicating that changes in apparent birefringence, caused by ATP‐calcium or by anoxia, are due to altered orientation of the myosin micelles and can be inhibited by agents that inhibit myosin ATPase activity.
The interaction of tumour‐localizing porphyrins with collagen, elastin, gelatin, fibrin and fibrinogen
Authors: El‐Far Mohamed A. , Pimstone Neville R. 
Published: May 2005

AbstractWe have already reported in Balb C mouse transplantable mammary carcinoma, that uroporphyrin I and III are superior as tumour localizers when compared to hematoporphyrin derivative and a derivative thereof, photofrin II. This study compares the binding of porphyrins to proteins which may be found in tumour cells or stroma to investigate whether there is a common binding determinant. Coproporphyrin III and deuteroporphyrin IX which are non‐tumour localizing porphyrins, were also part of the comparative study. The interaction of these porphyrins with acid soluble collagen and acid insoluble collagen, elastin, and fibrin was evaluated, and the binding of uroporphyrin isomers I and III and deuteroporphyrin IX to gelatin and fibrinogen, was also determined. The results suggest that collagen, especially the acid soluble form, and gelatin preferentially bind the four porphyrins which localize in mammary carcinoma tissue. The well reported observations that malignant epithelial cells, including breast cancer, produce collagen and contain a rate‐limiting enzyme in collagen biosynthesis would support the notion that de novo synthesis of this protein may in part govern the tumour uptake and retention of porphyrins. Elastin, Fibrinogen and fibrin showed non‐discriminant binding to the porphyrins under study.
Studies on mechanisms of ornithine decarboxylase activity regulation in regenerating liver
Authors: Zuretti M. F. , Gravela E. , Papino F. , Satorio L. 
Published: May 2005

AbstractRat liver (hydrocortisone‐induced) ornithine decarboxylase has been shown to be stable when the cytosolic fraction is incubated alone at 37°C, although there is a very rapid and drastic loss of activity after addition of microsomes to the incubation medium.The present paper is concerned with the behaviour of ornithine decarboxylase induced in rat liver by a growth stimulus (partial hepatectomy); comparative studies have been carried out on the enzyme induced by sham operation, or by hydrocortisone.Results show that ornithine decarboxylase from regenerating liver is more stable when incubated with microsomes (from the same source); this higher stability depends both on a lower microsome‐bound inactivating capacity and a limited susceptibility of the enzyme to the inactivation. A critical role in modulating the microsome‐dependent inactivation appears to be played by low molecular weight cytosolic factors, whose greater content in regenerating liver is likely to be included with the factors above in determining the relative stability of ornithine decarboxylase.
Stimulation by glucose and carbamylcholine of phospholipase C in pancreatic islets
Authors: Mathias P. C. F. , Best L. , Malaisse W. J. 
Published: May 2005

AbstractPhosphoinositide hydrolysis in intact pancreatic islet cells was investigated in an indirect but dynamic manner by monitoring the efflux of radioactivity from islets prelabelled with [3H]inositol. A rise in glucose concentration provoked a rapid, modest but sustained increase in effluent radioactivity, this phenomenon being abolished in the absence of extracellular Ca2+ or presence of verapamil. The release of [3H]inositol was also stimulated at high extracellular K+ concentration, but not by gliclazide. Whether in the presence or absence of glucose, carbamylcholine provoked a marked increase in effluent radioactivity. The response to the cholinergic agent was decreased in the presence of verapamil or absence of extracellular Ca2+ and abolished in the presence of atropine or LiCl. These results suggest that an increase in cytosolic Ca activity, as caused by glucose or membrane depolarization, may cause activation of phospholipase C. In response to cholinergic agents, however, the enzymic activation, although modulated by Ca2+ availability, may result directly from the occupation of muscarinic receptors.
Human bone cell cultures: A new model for studying the mechanism of action of calcitonin
Authors: Fanó G. , Maurizi M. , Venti‐Donti G. , Paludetti G. , Donti E. , Della Torre G. 
Published: May 2005

AbstractAn investigation on cell cultures obtained from temporal human bone fragments showed that they provide a suitable model for studying the mechanism involved in calcitonin action on bone cells. Furthermore they demonstrated: (1) a transitory increase in 45Ca uptake that returned to control values ten minutes after the hormone was added; (2) a relation between 45Ca uptake and increased cAMP concentrations when these were measured at the same time intervals; (3) a reproduction of the salmon calcitonin (sCT) effect after incubation of the cultures with either db‐cAMP or db‐cGMP and (4) inhibition of 45Ca uptake and parallel decrease in cAMP levels with propanol.These results suggest that in human bone cell cultures, sCT acts as a temporary promoter of 45Ca uptake, probably by activating an adenylate‐cyclase system through a β‐receptor.
The relevance of various tests for the study of specificity in immunocytochemical staining: A review
Authors: Van Der Sluis P. J. , Boer G. J. 
Published: May 2005

AbstractFactors determining the specificity of immunocytochemical (ICC) tissue stainings as well as the various tests to study these factors are discussed. Since every specificity test only deals with particular aspects of the ICC procedure, a practical sequence of known test methods is proposed, which enables the determination of the specificity of the ICC tissue staining and, after possibly needed antiserum purification steps, may result in a monospecific staining. It is made clear that such a sequence has always to include a tissue‐spectrum affinity test, in which the spectrum of tissue antigens is controlled for antibody binding. A variety of such tests, consisting of separation of tissue compounds, fixation, and ICC detection, are discussed as well as their pros and cons with respect to their predictability for the actual serum specificity in the tissue section.
The inhibitory effect of 4‐hydroxy‐nonenal on DNA‐polymerases alpha and beta from rat liver and rapidly dividing Yoshida ascites hepatoma
Authors: Wawra E. , Zollner H. , Schaur R. J. , Tillian H. M. , Schauenstein E. 
Published: May 2005

AbstractThe purpose of this study was to determine firstly whether the isolated enzyme DNA polymerase α, which functions within the DNA replicase system, exhibits different sensitivity against the thiol‐blocking agent 4‐hydroxy‐nonenal (HNE) when adult rat liver and the rapidly dividing Yoshida ascites hepatoma were used as enzyme sources and, secondly, whether the reaction catalysed by DNA polymerase is the most sensitive step of the DNA replicase system of native cells.DNA polymerase α as well as the non‐replicative DNA polymerase β, isolated from both sources, were remarkably similar with regard to their sensitivity against HNE, as indicated by the incorporation of radioactive label from [3H]deoxy‐thymidine‐triphosphate into DNA.The transport of [14C]thymidine through the plasma membrane and the incorporation of this precursor into DNA were studied with neonatal hepatocytes and with hepatoma cells. The incorporation of thymidine was inhibited at lower concentrations of HNE in both cell lines than the transport process and the reaction catalysed by DNA polymerase α. It was concluded that in the DNA replicase system of native liver and hepatoma cells another process different from the reaction catalysed by DNA polymerase α is more sensitive to HNE.
Enzymic heterogeneity of normal canine articular cartilage
Authors: Dunham Jane , Shackleton D. R. , Bitensky Lucille , Chayen J. , Billingham M. E. J. , Muir I. Helen 
Published: May 2005

AbstractArticular cartilage is generally considered to be an homogeneous tissue. It has now been shown that, although different regions of the medial tibial cartilage of the dog have very similar oxidative enzymic activities, each region is heterogeneous with respect to these activities. The conventional histological delineation of this cartilage has been modified, to take into account a narrow band (designated zone 2a), just below the most superficial spindle‐shaped cells, that has higher oxidative enzymic activity than any other. Changes in the activity in this zone might be diluted by the lack of change in other zones if measured by conventional biochemical procedures which could not measure the activities of the different zones separately.
Role of transferrin in iron transport between maternal and fetal circulations of a perfused lobule of human placenta
Authors: Contractor S. F. , Eaton B. M. 
Published: May 2005

AbstractThe transfer of iron between the maternal and fetal circulations of an isolated perfused lobule of term human placenta was investigated using125I‐labelled or59Fe‐labelled diferric transferrin. There was negligible transplacental transfer of intact transferrin whereas nearly 4 per cent of the added59Fe was transferred into the fetal circulation after 2 h, where it became associated with fetal transferrin. Over 20 per cent of the added59Fe radioactivity was sequestered within the placental tissue during this period, associated with transferrin, ferritin and other uncharacterized molecules. This suggests an important role for an intracellular pool in regulating transfer. The presence of 10 mMchloroquine in the maternal circulation substantially reduced tissue accumulation of59Fe and totally inhibited transfer to the fetus. It is concluded that the initial stages of iron transfer to the fetus involve the internalization of maternal iron‐saturated transferrin bound to membrane receptors by receptor‐mediated endocytosis, which can be inhibited by the drug chloroquine. Subsequently, the transplacental transfer of iron to the fetus does not involve the concommitant movement of transferrin.
Effect of amiodarone on Na+‐, K+‐ATPase and Mg2+‐ATPase activities in rat brain synaptosomes
Authors: Rao K. S. Prasada , Rao S. B. , Camus Ph. , Mehendale H. M. 
Published: May 2005

AbstractAmiodarone hydrochloride is a diiodinated antiarrhythmic agent widely used in the treatment of cardiac disorders. With the increasing use of amiodarone, several untoward effects have been recognized and neuropathy following amiodarone therapy has recently been reported. The present studies were carried out to study the effect of amiodarone on rat brain synaptosomal ATPase in an effort to understand its mechanism of action. Na+, K+‐ATPase and oligomycin sensitive Mg2+ ATPase activities were inhibited by amiodarone in a concentration dependent manner with IC50 values of 50 μM and 10 μM respectively. [3H]ouabain binding was also decreased in a concentration dependent manner with an IC50 value of 12 μM, and 50 μM amiodarone totally inhibited [3H]ouabain binding. Kinetics of [3H]ouabain binding studies revealed that amiodarone inhibition of [3H]ouabain binding is competitive. K+‐activated p‐nitrophenyl phosphatase activity showed a maximum inhibition of 32 per cent at 200 μM amiodarone. Synaptosomal ATPase activities did not show any change in rats treated with amiodarone (20mg kg−1 day−1) for 6 weeks, when compared to controls. The treatment period may be short, since the reported neurological abnormalities in patients were observed during 3–5 years of treatment. The present results suggest that amiodarone induced neuropathy may be due to its interference with sodium dependent phosphorylation of Na+, K+‐ATPase reaction, thereby affecting active ion transport phenomenon and oxidative phosphorylation resulting in low turnover of ATP in the nervous system.