bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination of lamivudine/stavudine/efavirenz in human serum using liquid chromatography/electrospray tandem mass spectrometry with ionization polarity switch
Authors: Fan Bin , Bartlett Michael G. , Stewart James T. 
Published: October 2002

AbstractA high‐performance liquid chromatography/tandem mass spectrometry (LC‐MS‐MS) method with ionization polarity switch was developed and validated in human serum for the determination of a lamivudine (3TC)/stavudine (d4T)/efavirenz combination HIV therapy. Solid phase extraction (SPE) was used to extract these anti‐HIV drugs and internal standard aprobarbital. A gradient mobile phase consisting of acetonitrile and 20 mM ammonium acetate buffer with pH adjusted to 4.5 using glacial acetic acid was utilized to separate these drugs on a hexylsilane column (150 × 2.0 mm i.d.). The total run time between injections was 18 min. The precursor and major product ions of these drugs were monitored on a triple quadrupole mass spectrometer in the multiple reactions monitoring (MRM) mode. Ionization polarity was switched in the middle of the LC run allowing these anti‐HIV drugs with different physicochemical properties to be detected simultaneously. The effect of ion suppression from human serum was studied and no interference with the analysis was noted. The method was validated over the range of 1.1–540 ng/mL for 3TC, 12.5–6228 ng/mL for d4T and 1.0–519 ng/mL for efavirenz. The method was shown to be accurate, with intra‐day and inter‐day accuracy less than 14.0% and precise, with intra‐day and inter‐day precision less than 13.1%. The extraction recoveries of all analytes were higher than 90%. Copyright © 2002 John Wiley & Sons, Ltd.
Development of a new assay for the screening of hypochlorous acid scavengers based on reversed‐phase high‐performance liquid chromatography
Authors: Gatto Maria Teresa , Firuzi Omidreza , Agostino Roberta , Grippa Eleonora , Borsò Angela , Spinelli Francesca , Pavan Lucia , Petrolati Marzia , Petrucci Rita , Marrosu Giancarlo , Saso Luciano 
Published: October 2002

AbstractA new assay for the screening of hypochlorite/hypochlorous acid (XOCl) scavengers, based on the reversed‐phase high performance liquid chromatographic analysis of human serum albumin (HSA, 0.2% in 100 mM sodium phosphate, pH 7), before and after oxidation by XOCl (1.6 mM), was developed. XOCl induced a significant decrease of the area under the chromatographic peak of HSA at 280 nm due to the oxidation of the aromatic amino acids tryptophan and tyrosine, as suggested by the literature and by the chromatographic analyses and the electrochemical study performed here. The assay was validated by testing known XOCl scavengers such as ascorbic acid, cysteine, glutathione, S‐methylglutathione and α‐lipoic acid and other antioxidants such as carnosine and chlorogenic acid, which inhibited the oxidation of HSA. Quantitative activities were calculated using an original formula based on the changes of the area of the albumin peak. Electrochemical data collected here in a homogeneous medium showed that the anodic potentials of the antioxidants tested are less positive (ascorbic acid, chlorogenic acid and cysteine) or similar (α‐lipoic acid) compared with those of the aromatic residues (tryptophan and tyrosine) of HSA oxidized by XOCl. However, as expected, carnosine, glutathione and S‐methylglutathione were inactive at a glassy‐carbon, gold or platinum electrode. Copyright © 2002 John Wiley & Sons, Ltd.
A preliminary evaluation of the functional significance of alpha‐1‐acid glycoprotein glycosylation on wound healing
Authors: French Deborah , Watson John , McCahill Breeda , Taggart Ian , Smith Kevin D. 
Published: October 2002

AbstractThe laying down of collagen and fibrous tissue is a key process in wound healing, however excessive collagen (and glycoprotein) deposition causes hypertrophic and keloid scars, eg after burns. Collagen synthesis is increased in these scars compared with normal healing, as is collagenase activity, which controls the degradation pathway of collagen. The processes of wound healing are inextricably linked to those of the acute‐phase response (APR): α‐1‐acid glycoprotein (AGP), a plasma glycoprotein that undergoes both an increase in concentration and an alteration in its glycosylation pattern during the APR. This study determined that AGP isolated from the plasma of burns patients was of an increased concentration and altered glycosylation pattern compared with normal plasma and was capable of directly interacting with type I collagen. It also had a profound effect on both collagen fibril formation and collagenase activity, to a degree dependent upon the percentage body surface area burned. Additionally, the results obtained provided the basis for predicting the formation of hypertrophic scars. Copyright © 2002 John Wiley & Sons, Ltd.
Semi‐micro liquid chromatography of aromatic amino acid metabolites using isocratic elution and Column switching
Authors: Hanai Toshihiko , Kaneko Kazuko , Homma H. 
Published: October 2002

AbstractThe concentrations of catecholamine‐related compounds in body fluids reflect sympathetic nerve functions. Measuring the enzyme activity of these metabolic pathways will improve diagnosis since a variety of symptoms are reported. An isocratic elution system with two column switching valves was developed using three types of semi‐micro columns for fast chromatographic analysis of catecholamine related compounds. Columns are a pentyl‐bonded phase, 50 × 2.1 mm i.d., a phenylhexyl‐bonded phase, 100 × 2.1 mm i.d. and an octadecyl‐bonded phase, 100 × 2.1 mm i.d. The separation of 20 standard compounds was achieved within 25 min using reversed‐phase ion‐pair liquid chromatography with an electrochemical detector. This new system was applied for analysis of catecholamine‐related compounds in pig brain, since pigs are a widely used animal model for transgenic manipulation of neural genes, and MHPG (or VMA), DOPAC, DOPA, NE, EP, DA, 5HTP and 5HIAA were quantified. Copyright © 2002 John Wiley & Sons, Ltd.
Beyond peripheral arteries in Buerger's disease: Angiographic considerations in thromboangiitis obliterans
Authors: Hoppe Bobbi , Lu Jonathan T. , Thistlewaite Patricia , Yi Eunhee S. , Mahmud Ehtisham 
Published: October 2002

AbstractThromboangiitis obliterans is an inflammatory peripheral vascular disease that is strongly associated with smoking. It predominantly affects distal small‐ and medium‐sized blood vessels of both the upper and lower extremities. We present histological evidence of this disease process affecting the internal mammary arteries. This can be of paramount clinical significance for patients with Buerger's disease who present with obstructive coronary artery disease and require coronary artery bypass grafting surgery (CABG). Internal mammary arteries involved with thromboangiitis obliterans cannot be utilized as arterial conduits during CABG and other alternatives have to be used. Therefore, we recommend preoperative angiography of both internal mammary arteries in patients with Buerger's disease requiring CABG to prevent extensive intraoperative dissection of diseased internal mammary arteries. Cathet Cardiovasc Intervent 2002;57:363–366. © 2002 Wiley‐Liss, Inc.
Photodynamic therapy: Applications in atherosclerotic vascular disease with motexafin lutetium
Authors: Chou Tony M. , Woodburn Kathryn W. , Cheong Wai‐Fung , Lacy Steven A. , Sudhir Krishnankutty , Adelman Daniel C. , Wahr Dennis 
Published: October 2002

AbstractPhotodynamic therapy (PDT) has been approved as a tissue‐specific light‐activated cytotoxic therapy for many diseases. The ability of PDT to destroy target tissues selectively is especially appealing for atherosclerotic plaque. Biotechnology has developed a new generation of selective photosensitizers and catheter‐based technological advances in light delivery have allowed the introduction of PDT into the vasculature. The largest experience to date is with motexafin lutetium (MLu, Antrin), an expanded porphyrin (texaphyrin) that accumulates in plaque. The combination of the motexafin lutetium and endovascular illumination, or Antrin phototherapy, has been shown to reduce plaque in animal models. Antrin phototherapy generates cytotoxic singlet oxygen that has been shown to induce apoptosis in macrophages and smooth muscle cells. The safety, tolerability, and preliminary efficacy of Antrin phototherapy has been assessed in a phase 1 dose‐ranging clinical trial in subjects with peripheral artery disease and is currently being examined in a phase 1 study in subjects with lesions of the native coronary arteries undergoing stent implantation. The preliminary results suggest that Antrin phototherapy is safe, well tolerated, and nontraumatic. Cathet Cardiovasc Intervent 2002;57:387–394. © 2002 Wiley‐Liss, Inc.
In vitro analysis of the origin, migratory behavior, and maturation of cortical pyramidal cells
Authors: Hatanaka Yumiko , Murakami Fujio 
Published: October 2002

AbstractDuring development neurons migrate from their site of origin to their final destinations under a variety of mechanisms. Although evidence has been accumulating that the cells from cortical ventricular zone (VZ) migrate radially and produce pyramidal cells, evidence that directly links the origin and the terminal phenotype of radially migrating cells has been limited. Further, the relation between the migratory behavior of these cells and their mature morphology remains obscure. To address these issues, we developed an in vitro preparation that enables visualization of cells derived from the cortical VZ. VZ cells of a rat cortex at embryonic days 18 to 19 were labeled by injecting green fluorescent protein (GFP)‐encoding plasmid into the lateral ventricle, followed by electroporation. The cortex was then sliced and cultured organotypically. After 1 day, GFP+ cells exhibited neural progenitor and radial glial cell natures. Over the next few days, many GFP+ cells migrated toward the pial surface, extending leading processes toward the pial surface and leaving a thin trailing process that almost reached the VZ. The leading processes of these neurons were positive for microtubule‐associated protein 2, and some transformed into dendritic arbor–like structures by day 5 or 6, and their trailing processes exhibited morphologic features indicative of prospective axons. Time‐lapse analysis confirmed extension of the trailing processes. Expression of molecular markers and morphologic analysis demonstrated that the vast majority of the migrated GFP+ cells differentiated into excitatory neurons with pyramidal cell–like morphology. These results strongly suggested that cells derived from the cortical VZ generate neurons that migrate radially. These neurons appeared to extend prospective dendrites in front and leave prospective axons behind, subsequently differentiating into pyramidal cells. J. Comp. Neurol. 454:1–14, 2002. © 2002 Wiley‐Liss, Inc.
Distribution of thyrotropin‐releasing hormone immunoreactivity in the brain of the dogfish Scyliorhinus canicula
Authors: Teijido Oscar , Manso María Jesús , Anadón Ramón 
Published: October 2002

AbstractTo improve knowledge of the peptidergic systems of elasmobranch brains, the distribution of thyrotropin‐releasing hormone‐immunoreactive (TRHir) neurons and fibers was studied in the brain of the small‐spotted dogfish (Scyliorhinus canicula L.). In the olfactory bulbs, small granule neurons richly innervated the olfactory glomeruli. In the telencephalic hemispheres, small TRHir neurons were observed in the superficial dorsal pallium, whereas TRHir fibers were widely distributed in pallial and subpallial regions. In the preoptic region, TRHir neurons formed a caudal ventrolateral group in the preoptic nucleus. In the hypothalamus, the most conspicuous TRHir populations were associated with the lateral hypothalamic recess, but small TRHir populations were found in the posterior tubercle and ventral wall of the posterior recess. The preoptic region and hypothalamus exhibited rich innervation by TRHir fibers. TRHir fibers were observed coursing to the neurohypophysis and the neuroepithelium of the saccus vasculosus, but not to the neurohemal region of the median eminence. Some stellate‐like TRHir cells were observed in a few cell cords of the neurointermediate lobe of the hypophysis. The thalamus, pretectum, and midbrain lacked TRHir neurons. Further TRHir neuronal populations were observed in the central gray and superior raphe nucleus of the isthmus, and a few TRHir cells were located in the nucleus of the trigeminal descending tract at the level of the rostral spinal cord. In the brainstem, the central gray, interpeduncular nucleus, secondary visceral region of the isthmus, rhombencephalic raphe, inferior olive, vagal lobe, and Cajal's commissural nucleus were all richly TRHir‐innervated. Comparison of the distribution of TRHir neurons observed in the dogfish brain with that observed in teleosts and tetrapods reveals strong resemblance but also interesting differences, indicating the presence of both a conserved basic vertebrate pattern and a number of derived characters. J. Comp. Neurol. 454:65–81, 2002. © 2002 Wiley‐Liss, Inc.
Digital necrosis associated with squamous cell carcinoma of the tonsil
Authors: Wright Jim R. , Gudelis Susan 
Published: October 2002

AbstractBackgroundDigital necrosis is an uncommon paraneoplastic syndrome. Fewer than 50 cases have been sporadically reported through the literature over the last 30 years.Case ReportWe describe the unfortunate case of a 62‐year‐old woman with a locally advanced squamous cell carcinoma of the tonsil. She was admitted to the hospital for symptomatic hypercalcemia and was found to have metastatic disease. She subsequently had digital necrosis develop. Despite numerous attempts to control the rapidly progressive ischemia, little objective evidence of response was noted. Her primary disease did not respond to palliative radiation, and her general condition rapidly deteriorated.ConclusionsA review of the literature provided some insight into the possible etiology of this unique complication of malignancy. Unfortunately, the treatment options suggested were of limited value, because there was no discernible benefit with any directed treatment. A brief summary and discussion of the literature follows. © 2002 Wiley Periodicals, Inc. Head Neck 24: 1019–1021, 2002
Approach for predicting the wetting front depth beneath a surface point source: theory and numerical aspect
Authors: Moncef Hammami , Hedi Daghari , Jelloul Balti , Mohamed Maalej 
Published: October 2002

AbstractUsing experimental data, the continuity and the cumulative infiltration equations, a new expression for predicting the wetted soil depth was described. Knowing soil hydraulic conductivity K(hf), initial and wetting front water content, this method enables us to calculate the maximum front depth Zf(t), beneath an emitter, by only measuring its radius Rf(t) on the soil surface.To test this, we used the ADI finite difference method to solve Richards' equation for axisymmetrical water infiltration from a point source on the soil surface. To simulate the evolution of the wetted soil volume dimensions (Rf(t) and Zf(t)), proper conditions were fixed for the wetting front boundaries.The Zf(t) predicted values were compared with those computed and measured during an axisymmetric water infiltration test on a silty soil for three different discharge rates. The results obtained showed good agreement between predicted, computed and measured data. Copyright © 2002 John Wiley & Sons, Ltd.
Feasibility of subsurface drainage for salinity control in the Trans‐Gangetic region of India
Authors: Datta K. K. , de Jong C. , Singh O. P. 
Published: October 2002

AbstractThe sustainability of irrigated agriculture in India is threatened by waterlogging, soil salinity and alkalinity. To reverse declining agricultural productivity, a combination of surface and subsurface drainage, supplemented by improved irrigation management, has been identified as the most appropriate strategy. But drainage for salinity control is costly. Therefore, the benefits in terms of sustained agricultural production must be thoroughly investigated to establish its techno‐economic feasibility. The present study attempts to do this by analysing: (i) the cost of installing subsurface drainage, (ii) the direct on‐farm benefits of subsurface drainage, and (iii) the financial feasibility of subsurface drainage.Haryana State was selected as the site of the study. The study shows that, after the installation of drainage, land utilization intensified as a sizeable area of formerly fallow land was brought under cultivation. It also shows that the cropping pattern changed in favour of more remunerative crops and that crop yields increased. This is an indication of the immediate gain from drainage, which helps to increase land productivity, gainful employment of the farmers and, hence, farm income. Recently (1997–98), mechanically installed large‐scale drainage development in the framework of the Indo‐Dutch Haryana Operational Pilot Project (HOPP) also supported the above findings. Given a sustainable solution for the disposal of the drainage effluent, the financial feasibility of drainage in waterlogged and saline areas looks favourable, provided that sufficient water is available for leaching and irrigation. Copyright © 2002 John Wiley & Sons, Ltd.
Individual and combined effect of waterlogging and salinity on crop yields in the Indus basin
Authors: Kahlown Muhammad Akram , Azam Muhammad 
Published: October 2002

AbstractWaterlogging and salinity are the major threats to the sustainability of irrigated agriculture in Pakistan. About 50% of the Culturable Command Area (CCA) in the Fordwah Eastern Sadiqia South (FESS) is affected by waterlogging and 12% by surface and profile salinity. A sample of 26 watercourses was selected in the project area to evaluate the individual and combined impacts of waterlogging and salinity on the yields of cotton, wheat, sugarcane and rice. The crop yields were measured separately for waterlogged fields and those affected with salinity and waterlogging simultaneously. The extent of yield loss as result of a rise in the water table from 1–2 m to less than 1 m was 27 and 33% for wheat and sugarcane crops, whereas it was 7 and 6% in the case of a drop of the water table to more than 2 m. For cotton, a rising water table from 2–3 m to 1–2 m and less than 1 m gave a yield decrease of about 11 and 60% respectively. The rice crop preferred waterlogging, and in contrast to other crops, gave about 7% less yield with a lowering of the water table from less than 1 m to 1–2 m. The wheat and sugarcane yields had decreasing trends with salinity in excess of 4 dS m−1 and had complete failures with salinity greater than 12 dS m−1 at water table depths of less than 1, 1–2 and 2–3 m. The cotton crop demonstrated relatively higher salinity tolerance under a water table deeper than 1 m. However, this crop could not survive at salinity levels in excess of 12 dS m−1 at water table depth of less than 1 m. The rice crop was a complete failure at salinity level of greater than 12 dS m−1 under water table depths of less than 1 and 1–2 m. The combined impact of waterlogging and salinity was more harmful to crop yields when compared with the individual effects of waterlogging. The combined analysis of waterlogging and salinity on crop yields provide a good sensitivity of the salinity‐yield relationships and indicated the importance of subsurface drainage. Copyright © 2002 John Wiley & Sons, Ltd.
Egg coats of the rock shrimp Rhynchocinetes typus: ultrastructural characterization and their function during fertilization
Authors: Palomino Jaime , Moreno Ricardo D. , Bustamante Eva , Messen Lucy , Dupré Enrique , Barros Claudio 
Published: October 2002

AbstractThe aim of the present work was to characterize structurally and ultrastructurally the egg coats of the rock shrimp, Rhynchocinetes typus, and to describe their functional roles during fertilization. Oocytes fixed directly from the ovary, have a total diameter of 549 µm and are covered by a 10‐µm‐thick transparent envelope. Electron microscope sections (dehydrated) of the egg envelope revealed an electron‐dense external coat of 0.4 µm covered by filamentous processes, and a granular inner coat of 4‐µm thickness. Oocytes placed for 5 min in seawater had a significantly larger diameter (573 µm), because of the increase in the thickness of the egg coats (32 µm) and the formation of a 16‐µm perivitelline space. The diameter of the egg proper was reduced by the same extent as the size of the perivitelline space. All these changes were associated to the loss of the egg fertilizability. SDS‐PAGE of isolated and solubilized egg coats with 20% β‐mercaptoethanol or 25 mM dithiothreitol (DTT) showed bands between 58 and 105 kDa and between 44 and 103 kDa, respectively. During normal fertilization, the sperm undergoes a drastic change in shape after first contact with the egg. We observed a similar change when solubilized egg coats were placed with vas deferens sperms. When the solubilized egg coat proteins were ultrafiltrated with a membrane of 10,000 MWCO (pore size) and then assayed for their effect on fertilization, an inhibitory effect of 30%, 41%, and 59% was found when oocytes were incubated with spermatozoa pre‐treated with 30, 60, and 120 µg/ml of proteins solubilized with β‐mercaptoethanol. A similar inhibitory effect was found when egg coat proteins solubilized with 25 mM DTT were used. Our results suggest that, in the shrimp, the egg coats play an active role during the morphological changes of the sperm during their passage through them. J. Exp. Zool. 293:632–640, 2002. © 2002 Wiley‐Liss, Inc.
Variation in plasma lipids during the reproductive cycle of male and female desert tortoises, Gopherus agassizii
Authors: Lance Valentine A. , Place Allen R. , Grumbles Janice S. , Rostal David C. 
Published: October 2002

AbstractPlasma triacylglycerol, phospholipid, cholesterol, cholesterol esters, fatty acids, and total lipids were measured in 30 female and 20 male desert tortoises (Gopherus agassizii) during the annual reproductive cycle in the eastern Mojave desert, Nevada. Blood samples were collected at monthly intervals from April to October. All lipid fractions, with the exception of free fatty acids, were significantly higher in female plasma than in male plasma in all months of the year. In contrast, free fatty acids were higher in male plasma than in female plasma in all months. The seasonal pattern in estradiol secretion mirrored that of triacylglycerol, phospholipid, cholesterol, and total lipid, all of which showed a significant correlation with the hormone. Estradiol and the vitellogenesis‐associated lipids were all significantly higher in August, September, October, and April than in June. The seasonal variation in cholesterol ester levels in females did not correlate with any of the reproductive events and did not appear to be involved in yolk precursor formation. Total lipid in males showed a negative correlation with testosterone and spermatogenesis. Individual fatty acids in the June and August samples (at the highest and lowest estradiol levels) were compared in male and female plasma. The percent of C18:3n3, C18:2n6, C18:1n9, C20:5n3, and C22:5 were significantly higher in the June female plasma sample than in the August sample. Docosahexanoic (C22:6n3) acid was barely detectable in female plasma in either month. J. Exp. Zool. 293:703–711, 2002. © 2002 Wiley‐Liss, Inc.