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Schwartz A, Fernández-Repollet E. Quantitative flow cytometry. Clin Lab Med 2001; 21:743-61. [PMID: 11770285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
Flow cytometers are instruments that can quantify fluorescence intensity data and provide unique information about cell populations. Significant advances have been made in terms of calibration reagents, evaluation of the quality and limitations of the monoclonal antibodies, standardized sample preparation, and data analysis to ensure interlaboratory comparability and reproducibility. Efforts to standardize quantitative fluorescence intensity measurements impact current clinical flow cytometry applications (i.e., immunophenotyping), but also emerging technologies, such as microarray assays, which also require calibration of fluorescence intensity across different platforms.
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Jost WH, Glaß J, Hueber R, Klein W, Reuter M, Schwartz A, Werner M. Autonomic Dysregulation in Parkinson Syndrome. AKTUELLE NEUROLOGIE 2001. [DOI: 10.1055/s-2001-18912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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103
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Bogard CJ, Trillo A, Schwartz A, Gerstel N. Future employment among homeless single mothers: the effects of full-time work experience and depressive symptomatology. Women Health 2001; 32:137-57. [PMID: 11459367 DOI: 10.1300/j013v32n01_07] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
This study examines the relationship between work and depressive symptomatology for extremely destitute single mothers-mothers who have experienced an episode of homelessness. Using longitudinal data collected from 294 respondents who became homeless in 1992 and were followed for approximately two years, we find that a history of full-time work is the best predictor of whether a woman will find full-time employment in the aftermath of an episode of homelessness. Even an extensive history of part-time or informal work was not predictive of finding employment after leaving a homeless shelter. A woman's level of depressive symptomatology at the onset of homelessness predicted her strategy in dealing with the shelter bureaucracy. Women with full-time work histories who experienced high levels of depressive moods at the onset of a shelter episode were likely to leave the shelter quickly. Those with lower levels of depressive symptomatology stayed and were more likely than others to complete an education or job training program. Both types of women with full-time work histories were more likely than others to find full-time employment after a homeless episode. These findings suggest that policy makers must focus on providing full-time, and not part-time, work for impoverished mothers and take depressive symptomatology into account when offering assistance to homeless mothers.
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104
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Muth JN, Varadi G, Schwartz A. Use of transgenic mice to study voltage-dependent Ca2+ channels. Trends Pharmacol Sci 2001; 22:526-32. [PMID: 11583810 DOI: 10.1016/s0165-6147(00)01797-1] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
During the past decade a great number of genes encoding high- and low-voltage-dependent Ca(2+) channels and their accessory subunits have been cloned. Studies of Ca(2+) channel structure-function relationships and channel regulation using cDNA expression in heterologous expression systems have revealed intricate details of subunit interaction, regulation of channels by protein kinase A (PKA) and protein kinase C (PKC), drug binding sites, mechanisms of drug action, the ion conduction pathway and other aspects of channel function. In recent years, however, we have arrived at the brink of an entirely new strategy to study Ca(2+) channels by overexpressing or knocking out genes encoding these channels in transgenic mice. In this article, various models of gene knockout or gene overexpression will be discussed. This new approach will reveal many secrets regarding Ca(2+) channel regulation and the control of Ca(2+)-dependent cellular processes.
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Wilkie DJ, Huang HY, Berry DL, Schwartz A, Lin YC, Ko NY, Chen A, Gralow J, Lindsley SK, Fitzgibbon D. Cancer symptom control: feasibility of a tailored, interactive computerized program for patients. FAMILY & COMMUNITY HEALTH 2001; 24:48-62. [PMID: 11563944] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
This study evaluated the feasibility of an innovative computerized symptom assessment tool, SymptomReport, and a computerized, tailored education tool, SymptomConsult, in a sample of 41 outpatients with cancer. After patients completed the computerized programs, an audiotaped telephone interview was conducted to assess patients' impressions. The study found that patients required less than 40 minutes on average to complete SymptomReport. The mean acceptability score was high 11 +/- 2. The 12 patients who completed SymptomConsult did so in an average of 20 minutes. The majority of participants indicated that the computer programs were easy, enjoyable, and informative tools. Initial formative research supports further study of these feasible computerized programs.
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106
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Joussen AM, Beecken WD, Moromizato Y, Schwartz A, Kirchhof B, Poulaki V. Inhibition of inflammatory corneal angiogenesis by TNP-470. Invest Ophthalmol Vis Sci 2001; 42:2510-6. [PMID: 11581191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023] Open
Abstract
PURPOSE To determine the efficacy of the angiogenic inhibitor TNP-470 on inflammatory corneal neovascularization. Topical and systemic delivery of the drug were investigated in a murine model as well as inhibition of endothelial cell proliferation in vitro and in vivo. METHODS The effect of TNP-470 on VEGF- and bFGF-stimulated bovine capillary endothelial (BCE) cell proliferation was evaluated in vitro. Corneal neovascularization was induced in vivo by mechanical debridement of the corneal and limbal epithelium with 0.15 M NaOH on C57BL6 mice. TNP-470 was administered systemically at 30 mg/kg body weight (BW) every other day or topically three times daily in a concentration of 5 ng/ml dissolved in methylcellulose. Vessel length was investigated on day 7. VEGF protein content in murine corneas was analyzed by ELISA on days 2, 4, and 7 of treatment. A modified bromouridine (BrdU) ELISA was used to quantify endothelial cell proliferation. RESULTS TNP-470 exerted a dose-dependent inhibition of bFGF- and VEGF-induced endothelial cell proliferation in vitro. Both systemic and topical application of TNP-470 led to a significant reduction of inflammatory corneal neovascularization (P < 1 x 10(-5)). BrdU labeling showed that TNP-470 inhibited endothelial cell proliferation. VEGF protein levels were reduced by systemic TNP-470 treatment. CONCLUSIONS These results suggest that TNP-470 reduces inflammatory corneal angiogenesis by directly inhibiting endothelial cell proliferation. Topical and systemic treatment with TNP-470 reduces VEGF levels that are responsible for vessel growth during the neovascularization process.
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Mori T, Takase H, Toide K, Hirano T, Kambe T, Nakayama N, Schwartz A. Pranidipine, a 1,4-dihydropyridine calcium channel blocker that enhances nitric oxide-induced vascular relaxation. CARDIOVASCULAR DRUG REVIEWS 2001; 19:1-8. [PMID: 11314598 DOI: 10.1111/j.1527-3466.2001.tb00179.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Pranidipine, a long acting 1,4-dihydropyridine calcium channel blocker, prolongs nitric oxide (NO)-mediated relaxation of rat aorta; it prolongs acetylcholine-induced relaxation in presence of endothelium as well as nitroglycerin-induced relaxation in absence of endothelium. In rat aorta the effect of pranidipine on NO-mediated relaxation is cyclic guanosine monophosphate (cGMP)-independent, but in guinea pig carotid artery the same effect of pranidipine is cGMP-dependent. It has been reported that in co-cultured human endothelial and smooth muscle cells pranidipine, at a higher concentration (10(-6) M), enhances vasorelaxant effect of NO by blocking NO decomposition. The enhancement of NO action by pranidipine differs from the direct NO-releasing action of other 1,4-dihydropyridines. It is expected that enhancement of NO-induced vasodilatation will lead to a venodilator action in vivo and less peripheral edema. The target organ protective effects of pranidipine are also reviewed in this article.
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Chang W, Pratt SA, Chen TH, Tu CL, Mikala G, Schwartz A, Shoback D. Parathyroid cells express dihydropyridine-sensitive cation currents and L-type calcium channel subunits. Am J Physiol Endocrinol Metab 2001; 281:E180-9. [PMID: 11404236 DOI: 10.1152/ajpendo.2001.281.1.e180] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Parathyroid cells express Ca2+ -conducting currents that are activated by raising the extracellular Ca2+ concentration ([Ca2+]o). We investigated the sensitivity of these currents to dihydropyridines, the expression of voltage-dependent Ca(2+) channel (VDCC) subunits, and the effects of dihydropyridines on the intracellular free [Ca2+] ([Ca2+]i) and secretion in these cells. Dihydropyridine channel antagonists dose dependently suppressed Ca2+ -conducting currents, and agonists partially reversed the inhibitory effects of the antagonists in these cells. From a bovine parathyroid cDNA library, we isolated cDNA fragments encoding parts of an alpha(1S)- and a beta(3)-subunit of L-type Ca(2+) channels. The alpha(1S)-subunit cDNA from the parathyroid represents an alternatively spliced variant lacking exon 29 of the corresponding gene. Northern blot analysis and immunocytochemistry confirmed the presence of transcripts and proteins for alpha(1)- and beta(3)-subunits in the parathyroid gland. The addition of dihydropyridines had no significant effects on high [Ca2+]o-induced changes in [Ca2+]i and parathyroid hormone (PTH) release. Thus our studies indicate that parathyroid cells express alternatively spliced L-type Ca2+ channel subunits, which do not modulate acute intracellular Ca2+ responses or changes in PTH release.
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Gardyn J, Schwartz A, Gal R, Lewinski U, Kristt D, Cohen AM. Waldenström's macroglobulinemia associated with AA amyloidosis. Int J Hematol 2001; 74:76-8. [PMID: 11530809 DOI: 10.1007/bf02982553] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
It is widely accepted that amyloidosis in Waldenström's macroglobulinemia (WM) is exclusively due to amyloid light-chain deposition. However, only a small number of previous reports have actually characterized the type of amyloid in WM. We now report the third patient with WM and amyloid A protein (AA) amyloidosis. This patient developed malabsorption, nephrotic syndrome, and orthostatic hypotension. AA was immunohistochemically demonstrated in the rectal biopsy. In conjunction with previous examples of AA amyloidosis, the present report raises the possibility that AA amyloidosis may also occur in WM patients.
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Schwartz A, Petrashevskaya NN. The importance of calcium in interpretation of NaK-ATPase isoform function in the mouse heart. Cardiovasc Res 2001; 51:9-12. [PMID: 11399242 DOI: 10.1016/s0008-6363(01)00336-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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111
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Warshofsky MK, Dominguez M, Eisenberg MS, Wasserman HS, Sciacca R, Wang W, Simon AD, Morse JH, Schwartz A, Anglés-Cano E, Rabbani LE. Elevated plasma tissue plasminogen activator and anti-THP-1 antibodies are independently associated with decreased graft survival in cardiac transplant recipients. Am J Cardiol 2001; 88:30-4. [PMID: 11423054 DOI: 10.1016/s0002-9149(01)01580-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Hemostatic and immunologic factors have been implicated in future cardiac events in patients with coronary artery disease. The role of these factors and their interaction is less established in cardiac transplant recipients. We sought to characterize the role of these factors in these patients. Cardiac transplant patients who presented for surveillance coronary angiography and/or endomyocardial biopsy were eligible for enrollment. Ninety-nine consecutive patients were enrolled. Plasma levels of tissue-type plasminogen activator (t-PA), plasminogen activator inhibitor-1, von Willebrand factor, fibrin D-dimer, and anti-t-PA antibody were determined by enzyme-linked immunosorbent assays. Anti-THP-1 cell antibodies directed against a monocytic leukemia cell line were detected by incubating patient plasma with THP-1 cells. Bound antibody was detected using goat peroxidase-labeled immunoglobulin G directed against human immunoglobulins. Lipids were measured by enzymatic methods. Multivariate analysis identified the presence of anti-THP-1 cell antibodies (risk ratio 4.41, p = 0.002), t-PA antigen (risk ratio 1.10, p = 0.033), donor age 20 to 26 years (risk ratio 8.83, p = 0.042), and donor age >36 years (risk ratio 15.53, p = 0.009) as predictors of allograft failure. Altered hemostatic function, as demonstrated by elevated plasma t-PA antigen levels, is predictive of subsequent allograft failure in cardiac transplant recipients. In addition, the presence of anti-THP-1 cell antibodies in these patients is predictive of allograft failure.
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Shamay Y, Raskin VI, Brandis AS, Steinberger HE, Marder JB, Schwartz A. Ozone treatment affects pigment precursor metabolism in pine seedlings. PHYSIOLOGIA PLANTARUM 2001; 112:285-292. [PMID: 11454235 DOI: 10.1034/j.1399-3054.2001.1120218.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Five-week-old seedlings of Pinus halepensis Mill. and Pinus brutia Ten. were exposed to air polluted with ozone (O3) (250 nl l-1, 12 h day-1 for 4 days) or to ambient air containing ca 10-20 nl l-1 O3, in the light (180 &mgr;mol m-2 s-1 photosynthetic photon flux density [PPFD], 12 h day-1) and then fed for 24 h in the light (100 &mgr;mol m-2 s-1 PPFD) with various radioactive precursors of chlorophyll (Chl) and carotene biosynthesis: 5-[4-14C]-aminolevulinic acid (14C-ALA), L-[14C(U)]-glutamic acid (14C-Glu), or D,L-[2-14C]-mevalonic acid (14C-MVA). Pigments were then extracted from cotyledons and fully expanded needles. Chl a and carotene were separated by thin-layer chromatography and high-performance liquid chromatography and their specific activities were determined. 14C-ALA and 14C-Glu labels were incorporated into Chl a and carotene. Exposure to O3 did not inhibit incorporation of 14C-ALA into Chl a molecules, but hydrolysis of Chl a showed that O3 inhibited phytol labelling of Chl a. Labelling of carotene was also inhibited by O3, but not when 14C-MVA was used as the label. These data suggest that O3 treatment inhibits (directly or indirectly) the biosynthesis of isoprenoids from products of ALA and Glu metabolism in the plastid, but not from MVA in the cytosol. This inhibition was more prominent when 14C-ALA was used as the label than when 14C-Glu was the labelling precursor. A significant increase in pheophorbide a, a tetrapyrrole component of Chl a labelling, and a concomitant decrease in phytol labelling was observed following incubation of O3-treated pine seedlings with 14C-ALA and 14C-Glu. Stronger inhibition of carotene biosynthesis and activation of Chl a tetrapyrrole labelling by 14C-ALA (in comparison with 14C-Glu) indicated that exposure to O3 inhibits the conversion of ALA to Glu as the first step in ALA catabolism. These results also suggested a more intensive Glu metabolism (in comparison with ALA) for carotene biosynthesis in the cytosol, as well as cooperation between two pathways of isopentenyl diphosphate biosynthesis.
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Ino M, Yoshinaga T, Wakamori M, Miyamoto N, Takahashi E, Sonoda J, Kagaya T, Oki T, Nagasu T, Nishizawa Y, Tanaka I, Imoto K, Aizawa S, Koch S, Schwartz A, Niidome T, Sawada K, Mori Y. Functional disorders of the sympathetic nervous system in mice lacking the alpha 1B subunit (Cav 2.2) of N-type calcium channels. Proc Natl Acad Sci U S A 2001; 98:5323-8. [PMID: 11296258 PMCID: PMC33208 DOI: 10.1073/pnas.081089398] [Citation(s) in RCA: 110] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
N-type voltage-dependent Ca(2+) channels (VDCCs), predominantly localized in the nervous system, have been considered to play an essential role in a variety of neuronal functions, including neurotransmitter release at sympathetic nerve terminals. As a direct approach to elucidating the physiological significance of N-type VDCCs, we have generated mice genetically deficient in the alpha(1B) subunit (Ca(v) 2.2). The alpha(1B)-deficient null mice, surprisingly, have a normal life span and are free from apparent behavioral defects. A complete and selective elimination of N-type currents, sensitive to omega-conotoxin GVIA, was observed without significant changes in the activity of other VDCC types in neuronal preparations of mutant mice. The baroreflex response, mediated by the sympathetic nervous system, was markedly reduced after bilateral carotid occlusion. In isolated left atria prepared from N-type-deficient mice, the positive inotropic responses to electrical sympathetic neuronal stimulation were dramatically decreased compared with those of normal mice. In contrast, parasympathetic nervous activity in the mutant mice was nearly identical to that of wild-type mice. Interestingly, the mutant mice showed sustained elevation of heart rate and blood pressure. These results provide direct evidence that N-type VDCCs are indispensable for the function of the sympathetic nervous system in circulatory regulation and indicate that N-type VDCC-deficient mice will be a useful model for studying disorders attributable to sympathetic nerve dysfunction.
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114
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Schwartz A, Koella JC. Trade-offs, conflicts of interest and manipulation in Plasmodium-mosquito interactions. Trends Parasitol 2001; 17:189-94. [PMID: 11282509 DOI: 10.1016/s1471-4922(00)01945-0] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
A long-held view among parasitologists is that infection by malaria parasites does not harm the mosquito vector. One of the reasons for this belief is that the two partners of the association share interests in the most important life-history traits of the mosquito. Both partners benefit from increased survival and an increased rate of bloodfeeding the mosquito to increase its reproductive success and the parasite to ensure its transmission. Problems with this line of reasoning appear when one considers possible trade-offs among the mosquito's life-history parameters, which constrain the attempts by the mosquito and the parasite to maximize their success. Could these constraints differ between the two partners and thus lead to conflicts of interest and what would be the evolutionary and epidemiological consequences of conflicting interests? These questions will be investigated below.
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Weng HR, Lee JI, Lenz FA, Schwartz A, Vierck C, Rowland L, Dougherty PM. Functional plasticity in primate somatosensory thalamus following chronic lesion of the ventral lateral spinal cord. Neuroscience 2001; 101:393-401. [PMID: 11074162 DOI: 10.1016/s0306-4522(00)00368-7] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The long-term consequences of thoracic spinothalamic tract lesion on the physiological properties of neurons in the ventral posterior lateral nucleus of the thalamus in monkeys were assessed. Neurons responding to both compressive and phasic brush stimuli (multireceptive neurons), but not brush-specific (low-threshold) neurons, in the partially deafferented thalamus showed increased spontaneous activity, increased responses evoked by cutaneous stimuli and larger mean receptive field size than the same types of cells in the thalamus with intact innervation. The spike train properties of both the spontaneous and evoked discharges of cells were also altered so that there was an increased incidence of spike-bursts in cells of deafferented thalamus. These changes were widespread in the thalamus, and included cells in both the fully innervated forelimb representation and the partially denervated hindlimb representation ipsilateral to the lesion. The spontaneous and evoked spike trains in the ipsilateral thalamus also show increased frequency of both spike-burst and non-burst events compared to the intact thalamus. These results indicate that chronic spinothalamic tract lesion produces widespread changes in the physiological properties of a discrete cell population of the thalamus.The findings in this study indicate that the thalamic processing of somatosensory information conveyed by the lemniscal system is altered by transection of the spinothalamic tract. This change in sensory processing in the thalamus would result in altered cortical processing of innocuous somatosensory inputs following deafferentation and so possibly contribute to the generation of the central pain syndrome.
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Lavid N, Schwartz A, Yarden O, Tel-Or E. The involvement of polyphenols and peroxidase activities in heavy-metal accumulation by epidermal glands of the waterlily (Nymphaeaceae). PLANTA 2001; 212:323-31. [PMID: 11289596 DOI: 10.1007/s004250000400] [Citation(s) in RCA: 108] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Co-localization of polyphenols and peroxidase activity was demonstrated in epidermal glands of the waterlily (Nymphaea) by histochemistry. Total phenols, tannins and peroxidase activity were determined quantitatively in plant extracts. Polyphenols were partially identified and were found to consist mainly of hydrolyzable tannins, gallic and tannic acid derivatives. Nymphaea polyphenols were shown to chelate Cr, Hg, and Pb in vitro, and Cd-binding by polymerized polyphenols was demonstrated in leaves exposed to Cd in vivo. Both polyphenols and peroxidases were found at very high constitutive levels, which were not induced or altered by external conditions, such as light and heavy-metal stress. It is suggested that the polymerization of polyphenols by peroxidases, enhanced after heavy-metal uptake and detoxification, is responsible for the binding of heavy metals in Nymphaea epidermal glands.
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117
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Orvieto R, Ben-Rafael Z, Schwartz A, Abir R, Fisch B, La-Marca A, Bar-Hava I. Soluble L-selectin levels during controlled ovarian hyperstimulation. Gynecol Endocrinol 2001; 15:29-33. [PMID: 11293921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
Abstract
We sought to determine whether neutrophil activation, as reflected by soluble L-selectin levels, plays a role in controlled ovarian hyperstimulation (COH) and the possible correlation between soluble L-selectin and serum sex steroid levels. The study population consisted of 14 consecutive patients undergoing our routine in vitro fertilization (IVF) long gonadotropin-releasing hormone (GnRH) analog protocol. Blood was drawn three times during the COH cycle: (1) on the day when adequate suppression was obtained (Day-S); (2) on the day of, or the day prior to, human chorionic gonadotropin (hCG) administration (Day-hCG); and (3) on the day of ovum pick-up (Day-OPU). Levels of sex steroids and plasma soluble leukocyte selectin (L-selectin) were compared among the three time points. Soluble L-selectin was measured with a commercial sandwich enzyme-linked immunosorbent assay (ELISA). The results showed significantly higher levels of soluble L-selectin on Day-OPU than on Day-S and Day-hCG, and significantly lower levels on Day-hCG than Day-S. Though no significant correlations were found between soluble L-selectin and serum estradiol or hCG levels, soluble L-selectin positively correlated with serum progesterone levels. We conclude that hCG administration leads to neutrophil activation, which correlates with the degree of luteinization. Further studies are required to elucidate the relationship between the immune system and COH. These may lead to new strategies for predicting and preventing complications of COH.
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118
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Serikov VB, Petrashevskaya NN, Canning AM, Schwartz A. Reduction of [Ca(2+)](i) restores uncoupled beta-adrenergic signaling in isolated perfused transgenic mouse hearts. Circ Res 2001; 88:9-11. [PMID: 11139467 DOI: 10.1161/01.res.88.1.9] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The effects of alterations in calcium in the perfusion media were studied on ss-adrenergic coupling in isolated hearts from 3 different transgenic mice: cardiac-specific overexpressed alpha(1) subunit of L-type calcium channel, overexpressed Galpha(q), and phospholamban knockout. Isolated hearts from all 3 models, when studied at [Ca(2+)] of 2 mmol/L in the perfusate, showed the usual blunted or no response to ss-adrenergic stimulation. Lowering [Ca(2+)] to 0.75 to 1.5 mmol/L unloaded the hearts of calcium and restored to nearly normal the responsiveness to ss-agonist stimulation.
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Brown LM, Hoover R, Silverman D, Baris D, Hayes R, Swanson GM, Schoenberg J, Greenberg R, Liff J, Schwartz A, Dosemeci M, Pottern L, Fraumeni JF. Excess incidence of squamous cell esophageal cancer among US Black men: role of social class and other risk factors. Am J Epidemiol 2001; 153:114-22. [PMID: 11159155 DOI: 10.1093/aje/153.2.114] [Citation(s) in RCA: 189] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Data from a population-based case-control study were used to evaluate the relation between social class factors and squamous cell esophageal cancer and the extent to which alcohol, tobacco, diet, and low income contribute to the higher incidence among Black men than among White men in the United States. A total of 347 male cases (119 White, 228 Black) and 1,354 male controls (743 White, 611 Black) were selected from three US geographic areas (Atlanta, Georgia, Detroit, Michigan, and New Jersey). Cases were residents of the study areas aged 30-79 years who had been diagnosed with histologically confirmed esophageal cancer between 1986 and 1989. The adjusted odds ratios for subjects with annual incomes less than $10,000 versus incomes of $25,000 or more were 4.3 (95% confidence interval: 2.1, 8.7) for Whites and 8.0 (95% confidence interval: 4.3, 15.0) for Blacks. The combination of all four major risk factors-low income, moderate/heavy alcohol intake, tobacco use, and infrequent consumption of raw fruits and vegetables-accounted for almost all of the squamous cell esophageal cancers in Whites (98%) and Blacks (99%) and for 99% of the excess incidence among Black men. Thus, lifestyle modifications, especially a lowered intake of alcoholic beverages, would markedly decrease the incidence of squamous cell esophageal cancer in both racial groups and would narrow the racial disparity in risk. Further studies on the determinants of social class may help to identify a new set of exposures for this tumor that are amenable to intervention.
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Muth JN, Bodi I, Lewis W, Varadi G, Schwartz A. A Ca(2+)-dependent transgenic model of cardiac hypertrophy: A role for protein kinase Calpha. Circulation 2001; 103:140-7. [PMID: 11136699 DOI: 10.1161/01.cir.103.1.140] [Citation(s) in RCA: 104] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Calcium imbalances have been implicated as an underlying mechanism of human cardiac dysfunction. The voltage-dependent calcium channel plays a critical role in calcium regulation in the heart. Thus, aberrant calcium signaling arising from this channel could initiate the calcium imbalances observed in heart failure. In the present study, we used a transgenic mouse with an increased number of L-type calcium channels to identify the role of an increased, sustained ingress of calcium as an initiator of hypertrophy. METHODS AND RESULTS Whole-heart histology and electrophysiology in isolated cardiomyocytes identified calcium-channel overexpression in the hearts of transgenic mice. Calcium-channel density was increased in 2-, 4-, and 8-month-old transgenic cardiomyocytes. Ventricular fibrosis, damage, and remodeling became more pronounced as the transgenic mice aged. Apoptosis was also present in transgenic hearts at 8 months of age. Increased protein kinase Calpha activation was elevated before the development of hypertrophy and failure. CONCLUSIONS Transgenic mice developed hypertrophy and severe cardiomyopathy as a function of age, thus confirming that changes in channel density are sufficient to induce disease. The small, sustained increase in the ingress of Ca(2+) through the calcium channel elevated protein kinase Calpha before the development of hypertrophy, suggesting that protein kinase Calpha plays an important role in triggering hypertrophy.
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Leng M, Locker D, Giraud-Panis MJ, Schwartz A, Intini FP, Natile G, Pisano C, Boccarelli A, Giordano D, Coluccia M. Replacement of an NH(3) by an iminoether in transplatin makes an antitumor drug from an inactive compound. Mol Pharmacol 2000; 58:1525-35. [PMID: 11093793 DOI: 10.1124/mol.58.6.1525] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
To investigate the modifications of antitumor activity and DNA binding mode of transplatin after replacement of one nonleaving group NH(3) by an iminoether group, trans-[PtCl(2)(Z-HN=C(OMe)Me)(NH(3)] and trans-[PtCl(2)(E-HN=C(OMe)Me)(NH(3)] complexes (differing in the Z or E configuration of iminoether, and abbreviated mixed Z and mixed E, respectively), have been synthesized. In a panel of human tumor cell lines, both mixed Z and mixed E show a cytotoxic potency higher than that of transplatin, the mean IC(50) values being 103, 37, and 215 microM, respectively. In vivo mixed Z is more active and less toxic than mixed E in murine P388 leukemia and retains its efficacy against SK-OV-3 human cancer cell xenograft in nude mice. In the reaction with naked DNA, mixed Z forms monofunctional adducts that do not evolve into intrastrand cross-links but close slowly into interstrand cross-links between complementary guanine and cytosine residues. The monofunctional mixed Z adducts are removed by thiourea and glutathione. The interstrand cross-links behave as hinge joints, increasing the flexibility of DNA double helix. The mixed Z, transplatin, and cisplatin interstrand cross-links, as well as mixed Z monofunctional adducts are not specifically recognized by HMG1 protein, which was confirmed to be able to specifically recognize cisplatin d(GpG) intrastrand cross-links. These data demonstrate that the DNA interaction properties of the antitumor-active mixed Z are very similar to those of transplatin, thus suggesting that clinical inactivity of transplatin could not depend upon its peculiar DNA binding mode.
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Schwartz A, Hupert J, Elstein AS, Noronha P. Evidence-based morning report for inpatient pediatrics rotations. ACADEMIC MEDICINE : JOURNAL OF THE ASSOCIATION OF AMERICAN MEDICAL COLLEGES 2000; 75:1229. [PMID: 11112728 DOI: 10.1097/00001888-200012000-00023] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The authors describe a patient-centered method for teaching evidence-based medicine that is part of the inpatient morning report for pediatrics residents at the University of Illinois at Chicago. With library support, residents search for evidence to answer their own questions about patients, and present it at morning report
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Reinstein E, Scheffner M, Oren M, Ciechanover A, Schwartz A. Degradation of the E7 human papillomavirus oncoprotein by the ubiquitin-proteasome system: targeting via ubiquitination of the N-terminal residue. Oncogene 2000; 19:5944-50. [PMID: 11127826 DOI: 10.1038/sj.onc.1203989] [Citation(s) in RCA: 131] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The E7 oncoprotein of the high risk human papillomavirus type 16 (HPV-16), which is etiologically associated with uterine cervical cancer, is a potent immortalizing and transforming agent. It probably exerts its oncogenic functions by interacting and altering the normal activity of cell cycle control proteins such as p21WAF1, p27KIP1 and pRb, transcriptional activators such as TBP and AP-1, and metabolic regulators such as M2-pyruvate kinase (M2-PK). Here we show that E7 is a short-lived protein and its degradation both in vitro and in vivo is mediated by the ubiquitin-proteasome pathway. Interestingly, ubiquitin does not attach to any of the two internal Lysine residues of E7. Substitution of these residues with Arg does not affect the ability of the protein to be conjugated and degraded; in contrast, addition of a Myc tag to the N-terminal but not to the C-terminal residue, stabilizes the protein. Also, deletion of the first 11 amino acid residues stabilizes the protein in cells. Taken together, these findings strongly suggest that, like MyoD and the Epstein Barr Virus (EBV) transforming Latent Membrane Protein 1 (LMPI), the first ubiquitin moiety is attached linearly to the free N-terminal residue of E7. Additional ubiquitin moieties are then attached to an internal Lys residue of the previously conjugated molecule. The involvement of E7 in many diverse and apparently unrelated processes requires tight regulation of its function and cellular level, which is controlled in this case by ubiquitin-mediated proteolysis.
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Koch SE, Bodi I, Schwartz A, Varadi G. Architecture of Ca(2+) channel pore-lining segments revealed by covalent modification of substituted cysteines. J Biol Chem 2000; 275:34493-500. [PMID: 10950957 DOI: 10.1074/jbc.m005569200] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The cysteine accessibility method was used to explore calcium channel pore topology. Cysteine mutations were introduced into the SS1-SS2 segments of Motifs I-IV of the human cardiac L-type calcium channel, expressed in Xenopus oocytes and the current block by methanethiosulfonate compounds was measured. Our studies revealed that several consecutive mutants of motifs II and III are accessible to methanethiosulfonates, suggesting that these segments exist as random coils. Motif I cysteine mutants exhibited an intermittent sensitivity to these compounds, providing evidence for a beta-sheet secondary structure. Motif IV showed a periodic sensitivity, suggesting the presence of an alpha-helix. These studies reveal that the SS1-SS2 segment repeat in each motif have non-uniform secondary structures. Thus, the channel architecture evolves as a highly distorted 4-fold pore symmetry.
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Orvieto R, Schwartz A, Bar-Hava I, Abir R, Ashkenazi J, La-Marca A, Ben-Rafael Z. Controlled ovarian hyperstimulation--a state of endothelial activation. Am J Reprod Immunol 2000; 44:257-60. [PMID: 11125785 DOI: 10.1111/j.8755-8920.2000.440501.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
PROBLEM To aim of the study was to investigate whether controlled ovarian hyperstimulation (COH) causes endothelial activation and whether there is a correlation between endothelial activation and serum sex-steroid levels. METHOD OF STUDY The study population consisted of 14 consecutive patients undergoing our routine IVF long gonadotropin-releasing hormone-analog protocol. Blood was drawn three times during the COH cycle: (1) day when adequate suppression was obtained (Day-S); (2) on the day of or the day prior to hCG administration (Day-hCG); and (3) on the day of ovum pick-up (Day-OPU). The levels of sex steroids and plasma soluble endothelial (E)-selectin were compared among the time points. Soluble E-selectin was measured with a commercial sandwich enzyme-linked immunosorbent assay. RESULTS Soluble E-selectin levels were significantly higher on Day-OPU than Day-S and Day-hCG, whereas no difference was observed between Day-hCG and Day-S. No significant correlations were found between soluble E-selectin level and patient age, number of gonadotropin ampoules used, number of oocytes retrieved, or serum estradiol, progesterone and human chorionic gonadotropin levels. CONCLUSIONS Human chorionic gonadotropin administration leads to endothelial activation regardless of the degree of ovarian response. Further studies are required to elucidate the relationship between COH and endothelial activation. These findings may lead to new strategies for predicting and preventing complications of COH, such as severe ovarian hyperstimulation syndrome.
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