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Prenatal mother-father cortisol linkage predicts infant executive functions at 24 months. Dev Psychobiol 2021; 63:e22151. [PMID: 34674244 DOI: 10.1002/dev.22151] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 05/14/2021] [Accepted: 05/17/2021] [Indexed: 01/19/2023]
Abstract
The present study investigated associations between prenatal mother-father cortisol linkage and infant executive functions. Data come from an international sample (N = 358) of predominantly white and middle- to upper-class first-time parents. During late pregnancy, parents collected diurnal salivary cortisol samples and reported on levels of psychological stress. At 24 months, children completed a battery of executive function tasks. Parent cortisol linkage was operationalized as the time-dependent, within-dyad association between maternal and paternal diurnal cortisol. Results indicated that prenatal linkage was positively related to infant executive functions, suggesting that stronger mother-father cortisol linkage was associated with higher executive function scores. Additionally, this relation was moderated by paternal average cortisol levels such that executive function scores were lower when fathers had higher average cortisol levels and linkage was weak. This association suggests that elevated paternal cortisol amplifies the negative relation between lower cortisol linkage and lower infant executive function scores. Importantly, these findings were observed while controlling for observational measures of caregiving and self-report measures of psychosocial functioning and infant social-emotional behavior. These results suggest that prenatal linkage of mother's and father's stress physiology plays a potentially important part in programming and regulating infant neurocognitive development.
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Innovating Maternal and Child Health: Incentive Prizes to Improve Early Childhood Development. Matern Child Health J 2021; 25:1508-1515. [PMID: 34398407 DOI: 10.1007/s10995-021-03219-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/07/2021] [Indexed: 11/25/2022]
Abstract
PURPOSE Protecting and advancing maternal and child health is a critical goal to both society and to the economy, given that their health is a predictor of the next generation's health. Yet despite this recognition, many of the communities aiming to improve maternal and child health still problem-solve in silos: age silos, disease silos, organizational silos, disciplinary silos, data silos, and communication silos, often created or exacerbated by the disconnected approaches to research, funding, and reporting. These silos limit discovery and spread of new solutions to important maternal and child health problems. DESCRIPTION In this paper, we will discuss federal incentive prizes as a tool to break down silos and to engineer cognitive diversity and transdisciplinary collaboration. ASSESSMENT In 2018, the United States Health Resources and Services Administration, Maternal and Child Health Bureau (HRSA MCHB) launched the "Maternal and Child Health Bureau Grand Challenges," a suite of four prize competitions totaling $1.5 million addressing critical issues in maternal and child health. These included federal challenges designed to (1) prevent childhood obesity in low-income communities, (2) improve the remote monitoring of pregnancy, (3) improve care coordination and planning for children with special health care needs, and (4) prevent opioid misuse among pregnant women and new mothers. CONCLUSION The ability to incentivize innovation to address critical public health issues cannot rest in the private sector alone. Complementing other investments, the Challenge mechanism's power to catalyze the rapid development of innovative solutions can improve how we address barriers to achieve optimal maternal and child health for the families that we serve.
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Háblame Bebé: A phone application intervention to support Hispanic children's early language environments and bilingualism. CHILD LANGUAGE TEACHING AND THERAPY 2020; 36:33-57. [PMID: 35875512 PMCID: PMC9307223 DOI: 10.1177/0265659020903779] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The early language environments of low-income Hispanic children can be negatively affected when their Spanish-speaking caregivers face racism, assimilation pressure, and/or misinformed advice based on English-only ideologies. This article reports on the design and efficacy of Háblame Bebé, a language-promoting phone application that encourages low-income Hispanic mothers to talk more to their children in their native Spanish with the goals of (1) improving their children's early language environment, (2) promoting bilingualism, and (3) monitoring developmental milestones. The app was designed and tested across three phases as mandated by the US HRSA Bridging the Word Gap Challenge. In Phase I, we developed a curriculum that promotes high-quality language interactions in Spanish and designed the app components. In Phase II, we tested the app with 20 Hispanic mothers (half high school-educated, half college-educated) in a pretest-posttest design in which we examined their language interactions before and after two months of using the app. Preliminary results indicated that mother-child verbal interactions increased, but not always in their native Spanish, and the difference was not statistically significant. Focus group data revealed that many of the mothers had experienced linguistic racism and that tropes surrounding Spanish-speaking identity in the USA needed to be explicitly addressed within the intervention. In Phase III, a sociolinguistic pride component was added and the app was again tested with 12 additional Hispanic mothers (all high school-educated only). This time, a statistically significant increase in mother-child verbal interactions was found. Mothers also reported feeling prouder to use Spanish with their children. These results suggest that Háblame Bebé may be a viable means to reach low-income Hispanic caregivers who face obstacles in accessing health information and/or home-visiting programs for their children.
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Delivering services to incarcerated teen fathers: A pilot intervention to increase the quality of father–infant interactions during visitation. Psychol Serv 2014; 11:10-21. [DOI: 10.1037/a0034877] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Flexible memory retrieval in bilingual 6-month-old infants. Dev Psychobiol 2013; 56:1156-63. [DOI: 10.1002/dev.21188] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2013] [Accepted: 11/18/2013] [Indexed: 11/11/2022]
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Revisiting the effect of reminders on infants' media memories: does the encoding format matter? Dev Psychol 2013; 49:2112-9. [PMID: 23356528 DOI: 10.1037/a0031759] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
With the present research, the authors examined whether reminders could maintain 18-month-olds' memories generated from picture books and videos. Infants (N = 98) were shown a series of target actions in a picture book or on video. Either 24 hr or 2 weeks prior to a 4-week deferred imitation test, they were exposed to a reminder, a partial presentation of the original media demonstration. After both reminder delays, groups that received a video demonstration and a video reminder (video/video) performed significantly better than did the video-reminder-only control group (x/video), but groups that received a picture-book demonstration and a picture-book reminder (book/book) did not perform better than did the picture-book-reminder-only control (x/book). Additionally, if reminders did not veridically match the conditions of encoding (e.g., video demonstration and a book reminder, video/book or vice versa), infants also failed to perform better than controls. Theoretical implications for the understanding of long-term memory processing during early childhood and practical implications for early multimedia usage are discussed.
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Long-term transfer of learning from books and video during toddlerhood. J Exp Child Psychol 2012; 111:108-19. [PMID: 21911223 PMCID: PMC3185162 DOI: 10.1016/j.jecp.2011.08.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2011] [Revised: 08/05/2011] [Accepted: 08/07/2011] [Indexed: 11/23/2022]
Abstract
Television viewing and picture book reading are prevalent activities during toddlerhood, and research has shown that toddlers can imitate from both books and videos after short delays. This is the first study to directly compare toddlers' long-term retention rates for target actions learned from a video or book. Toddlers (N=158) at 18- and 24-months of age saw an experimenter demonstrating how to make a novel three-step toy rattle via a prerecorded video or a picture book. The toddlers' imitation of the target actions was tested after a specific delay (e.g., 2, 4 weeks), and their performance was compared with that of age-matched controls who did not see a demonstration. The 18-month-olds retained the target actions for 2 weeks, exhibiting forgetting at 4 weeks, whereas the 24-month-olds retained the information for up to 4 weeks, exhibiting forgetting at 8 weeks. Retention rates for books and videos did not differ at either age. These findings demonstrate very impressive retention from a brief two-dimensional media demonstration, and they contribute to our overall understanding of long-term memory processes during infancy.
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Abstract
Hansenula polymorpha mutants disrupted in the high-affinity nitrate transporter gene (YNT1) are still able to grow in nitrate. To detect the nitrate transporter(s) responsible for this growth a strain containing disruption of the nitrate assimilation gene cluster and expressing nitrate reductase gene (YNR1) under the control of H. polymorpha MOX1 (methanol oxidase) promoter was used (FM31 strain). In this strain nitrate taken up is transformed into nitrite by nitrate reductase and excreted to the medium where it is easily detected. Nitrate uptake which is neither induced by nitrate nor repressed by reduced nitrogen sources was detected in the FM31 strain. Likewise, nitrate uptake detected in the strain FM31 is independent of both Ynt1p and Yna1p and is not affected by ammonium, glutamine or chlorate. The inhibition of nitrite extrusion by extracellular nitrite suggests that the nitrate uptake system shown in the FM31 strain could also be involved in nitrite uptake.
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Cloning, sequencing, and expression of H.a.YNR1 and H.a.YNI1, encoding nitrate and nitrite reductases in the yeast Hansenula anomala. Yeast 2000; 16:1099-105. [PMID: 10953081 DOI: 10.1002/1097-0061(20000915)16:12<1099::aid-yea596>3.0.co;2-s] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A single Hansenula anomala genomic DNA fragment containing the genes H.a.YNR1 (yeast nitrate reductase) and H.a.YNI1 (yeast nitrite reductase) encoding nitrate and nitrite reductase, respectively, was isolated from a lambda EMBL3 genomic DNA library. As probe, a 3.2 kb DNA fragment isolated from a lambda gt11 H. anomala genomic DNA library screened with antiserum anti-NR from H. anomala was used. H. a.YNR1 and H.a.YNI1 genes are separated by 473 bp and encode putative proteins of 870 and 1077 amino acids, respectively, with great similarity to nitrate and nitrite reductases from other organisms. Northern blot analysis revealed that both genes are highly expressed in nitrate, very low in nitrate plus ammonium, and no expression was detected in ammonium or nitrogen-free media. Levels of nitrate reductase and nitrite reductase were very low or undetectable by Western blot analysis in nitrogen-free and ammonium media, whereas both proteins were present in nitrate and ammonium plus nitrate media. The nucleotide sequence Accession No. is AF123281.
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Anti-tuberculosis drug resistance in two clinics in Ecuador. Int J Tuberc Lung Dis 2000; 4:115-7. [PMID: 10694088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
SETTING Two private hospitals, one in the capital city and one in the eastern rainforest of Ecuador. OBJECTIVE To document the prevalence of anti-tuberculosis drug resistance in Ecuador in patients who had not received prior treatment and in those who had. DESIGN Drug resistance was determined using the proportion method with solid medium on the first isolate of Mycobacterium tuberculosis from all patients who attended the two hospitals between 1989 and 1996. Documentation of prior treatment was obtained by patient interview. RESULTS Resistance was identified in 39 of 161 patients (24%) who had had no prior treatment. Resistance was 14.2% to isoniazid, 11.8% to rifampin and 8.7% to both (multidrug-resistant tuberculosis). Among 60 patients who had received prior treatment, 18 (30%) were resistant to isoniazid, and 14 (23.3%) to rifampin, while multidrug resistance was seen in 10 (16.7%). CONCLUSION In these populations the prevalence of resistance both in patients with no prior treatment and in patients with prior treatment was ominously high. The initial treatment regimens and patient management in Ecuador should be re-evaluated in an effort to prevent further increases in drug resistance.
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Abstract
Previous evidence based on the experience of our laboratory showed that one-step gene disruption in the yeast Hansenula polymorpha is not straightforward. A systematic study of several factors which could affect gene disruption frequency was carried out. We found that the more critical factor affecting one-step gene disruption in H. polymorpha is the length of the target gene region flanking the marker gene. Target gene regions of about 1 kb flanking the marker gene were necessary to obtain a disruption frequency of about 50%. However, the gene marker, either homologous or heterologous, the locus and the strain examined did not significantly affect the frequency of disruption; the highest disruption frequency obtained for the YNR1 gene was in the strain HMI39, using the Saccharomyces cerevisiae URA3 gene as a marker. Since long regions flanking the gene marker do not allow the easy PCR-mediated strategies, developed for S. cerevisiae, to obtain constructs to disrupt a given gene in H. polymorpha, an alternative PCR strategy was developed.
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Clustering of the YNA1 gene encoding a Zn(II)2Cys6 transcriptional factor in the yeast Hansenula polymorpha with the nitrate assimilation genes YNT1, YNI1 and YNR1, and its involvement in their transcriptional activation. Biochem J 1998; 335 ( Pt 3):647-52. [PMID: 9794807 PMCID: PMC1219828 DOI: 10.1042/bj3350647] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The genes encoding the nitrate transporter (YNT1), nitrite reductase (YNI1) and nitrate reductase (YNR1) are clustered in the yeast Hansenula polymorpha. In addition, DNA sequencing of the region containing these genes demonstrated that a new open reading frame called YNA1 (yeast nitrate assimilation) was located between YNR1 and YNI1. The YNA1 gene encodes a protein of 529 residues belonging to the family of Zn(II)2Cys6 fungal transcriptional factors, and has the highest similarity to the transcriptional factors encoded by nirA, and to a smaller extent to nit-4, involved in the nitrate induction of the gene involved in the assimilation of this compound in filamentous fungi. Northern blot analysis showed the presence of the YNA1 transcript in cells incubated in nitrate, nitrate plus ammonium, ammonium, and nitrogen-free media, with a decrease in its levels in those cells incubated in ammonium. In nitrate the strain Deltayna1::URA3, with a disrupted YNA1 gene, neither grew nor expressed the genes YNT1, YNI1 and YNR1. In the gene cluster YNT1-YNI1-YNA1-YNR1, the four genes were transcribed independently in the YNT1-->YNR1 direction and the transcription start sites were determined by primer extension.
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The YNT1 gene encoding the nitrate transporter in the yeast Hansenula polymorpha is clustered with genes YNI1 and YNR1 encoding nitrite reductase and nitrate reductase, and its disruption causes inability to grow in nitrate. Biochem J 1997; 321 ( Pt 2):397-403. [PMID: 9020872 PMCID: PMC1218082 DOI: 10.1042/bj3210397] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
DNA sequencing in the phage lambda JA13 isolated from a lambda EMBL3 Hansenula polymorpha genomic DNA library containing the nitrate reductase-(YNR1) and nitrite reductase-(YNI1) encoding genes revealed an open reading frame (YNT1) of 1524 nucleotides encoding a putative protein of 508 amino acids with great similarity to the nitrate transporters from Aspergillus nidulans and Chlamydomonas reinhardtii. Disruption of the chromosomal YNT1 copy resulted in incapacity to grow in nitrate and a significant reduction in rate of nitrate uptake. The disrupted strain is still sensitive to chlorate, and, in the presence of 0.1 mM nitrate, the expression of YNR1 and YNI1 and the activity of nitrate reductase and nitrite reductase are significantly reduced compared with the wild-type. Northern-blot analysis showed that YNT1 is expressed when the yeast is grown in nitrate and nitrite but not in ammonium solution.
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The genes YNI1 and YNR1, encoding nitrite reductase and nitrate reductase respectively in the yeast Hansenula polymorpha, are clustered and co-ordinately regulated. Biochem J 1996; 317 ( Pt 1):89-95. [PMID: 8694791 PMCID: PMC1217490 DOI: 10.1042/bj3170089] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The nitrite reductase-encoding gene (YNI1) from the yeast Hansenula polymorpha was isolated from a lambda EMBL3 H. polymorpha genomic DNA library, using as a probe a 481 bp DNA fragment from the gene of Aspergillus nidulans encoding nitrite reductase (niiA). An open reading frame of 3132 bp, encoding a putative protein of 1044 amino acids with high similarity with nitrite reductases from fungi, was located by DNA sequencing in the phages lambdaNB5 and lambdaJA13. Genes YNI1 and YNR1 (encoding nitrate reductase) are clustered, separated by 1700 bp. Northern blot analysis showed that expression of YNI1 and YNR1 is co-ordinately regulated; induced by nitrate and nitrite and repressed by sources of reduced nitrogen, even in the presence of nitrate. A mutant lacking nitrite reductase activity was obtained by deletion of the chromosomal copy of YNI1. The mutant does not grow in nitrate or in nitrite; it exhibits a similar level of transcription of YNR1 to the wild type, but the nitrate reductase enzymic activity is only about 50% of the wild type. In the presence of nitrate the delta ynil::URA3 mutant extrudes approx. 24 nmol of nitrite/h per mg of yeast (wet weight), about five times more than the wild type.
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Functional analysis by site-directed mutagenesis of individual amino acid residues in the flavin domain of Neurospora crassa nitrate reductase. MOLECULAR & GENERAL GENETICS : MGG 1995; 249:456-64. [PMID: 8552051 DOI: 10.1007/bf00287108] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Nitrate reductase of Neurospora crassa is a complex multi-redox protein composed of two identical subunits, each of which contains three distinct domains, an amino-terminal domain that contains a molybdopterin cofactor, a central heme-containing domain, and a carboxy-terminal domain which binds a flavin and a pyridine nucleotide cofactor. The flavin domain of nitrate reductase appears to have structural and functional similarity to ferredoxin NADPH reductase (FNR). Using the crystal structure of FNR and amino acid identities in numerous nitrate reductases as guides, site-directed mutagenesis was used to replace specific amino acids suspected to be involved in the binding of the flavin or pyridine nucleotide cofactors and thus important for the catalytic function of the flavin domain. Each mutant flavin domain protein was expressed in Escherichia coli and analyzed for NADPH: ferricyanide reductase activity. The effect of each amino acid substitution upon the activity of the complete nitrate reductase reaction was also examined by transforming each manipulated gene into a nit-3- null mutant of N. crassa. Our results identify amino acid residues which are critical for function of the flavin domain of nitrate reductase and appear to be important for the binding of the flavin or the pyridine nucleotide cofactors.
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Cloning and disruption of the YNR1 gene encoding the nitrate reductase apoenzyme of the yeast Hansenula polymorpha. FEBS Lett 1995; 366:137-42. [PMID: 7789531 DOI: 10.1016/0014-5793(95)00511-7] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The nitrate reductase gene (YNR1) from the yeast H. polymorpha was isolated from a lambda EMBL3 genomic DNA library. As probe a 350 bp DNA fragment synthesized by PCR from H. polymorpha cDNA was used. By DNA sequencing an ORF of 2,577 bp was found. The predicted protein has 859 amino acids and presents high identity with nitrate reductases from other organisms. Chromosomal disruption of YNR1 causes inability to grow in nitrate. Northern blot analysis showed that YNR1 expression is induced by nitrate and repressed by ammonium.
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Nitrite causes reversible inactivation of nitrate reductase in the yeast Hansenula anomala. MICROBIOLOGY (READING, ENGLAND) 1994; 140 ( Pt 10):2633-7. [PMID: 8000533 DOI: 10.1099/00221287-140-10-2633] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The addition of nitrite, the product of the reaction catalysed by nitrate reductase, to cell suspensions of the yeast Hansenula anomala caused a reversible inactivation of NADPH-dependent nitrate reductase activity. The haem- and Mo-dependent and Mo-dependent activities of nitrate reductase, determined with the non-physiological electron donors FMNH2 and reduced methyl viologen respectively, were less affected. A similar inactivation was found with the proton ionophores 2,4-dinitrophenol and carbonyl cyanide m-chlorophenylhydrazone. The inactive enzyme was found in the particulate fraction and cosedimented with the mitochondrial fraction. When the NADPH-dependent nitrate reductase activity was restored in vivo the enzyme was found in the soluble fraction. The inactivation of nitrate reductase by nitrite, 2,4-dinitrophenol and carbonyl cyanide m-chlorophenylhydrazone was dependent on the external pH. The treatment of isolated mitochondria at alkaline pH with Triton X-100 solubilized about 30% of the inactive enzyme.
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Hypersensitive sites in the 5' promoter region of nit-3, a highly regulated structural gene of Neurospora crassa. J Bacteriol 1993; 175:6755-9. [PMID: 8226616 PMCID: PMC206797 DOI: 10.1128/jb.175.21.6755-6759.1993] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The nit-3 gene of the filamentous fungus Neurospora crassa encodes nitrate reductase, the enzyme which catalyzes the first step in nitrate assimilation. The nit-3 gene is subject to a high degree of regulation by metabolic inducers and repressors, and its expression requires two distinct trans-acting regulatory proteins. Hypersensitive sites in the 5' DNA sequence upstream of the nit-3 gene were mapped with the use of three different nucleases as molecular probes. Six hypersensitive sites, three of which are very strong, were detected at essentially identical positions by all three nucleases. The hypersensitive sites appear to develop in a constitutive fashion and are present under conditions in which the nit-3 structural gene is expressed but also when this gene is inactive, although these sites are considerably less prominent in cells subjected to nitrogen catabolite repression. The presence of the hypersensitive sites appears to depend upon both the positively acting NIT2 and the positively acting NIT4 regulatory proteins, which might play a role in positioning of chromatin protein.
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[Not Available]. CADERNOS DA CASA DE OSWALDO CRUZ 1989; 1:77-83. [PMID: 11636427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
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Abstract
The role of alpha 1-adrenergic receptors (adrenoceptors) on cardiac contractility was investigated in human subjects. The effect of methoxamine, a selective alpha-adrenoceptor agonist, and angiotensin II, on cardiac contractility was determined by means of noninvasive assessment of the slope of the end-systolic pressure (ESP)/end-systolic dimension (ESD) relationship. The slope (m) of this ratio was significantly higher with methoxamine (17.0; SD = 9.0 mm Hg/mm) than with angiotensin II (4.8; SD = 1.9 mm Hg/mm) (p less than 0.05). Slopes with methoxamine were higher when heart rates (HRs) were reflexly reduced, and were significantly diminished when reflex bradycardia was prevented by atropine (p less than 0.05) or atrial pacing (p less than 0.01). Previous treatment with propranolol did not modify m values with methoxamine (m = 15.5; SD = 4.4 mm Hg/mm). Phentolamine, given at peak methoxamine effect, did not consistently modify m values, resulting in an average slope not significantly different from that obtained with methoxamine alone. However, the addition of phentolamine did not cause an increase in ESDs at each level of ESP with respect to methoxamine. In the same subjects, infusion of phentolamine after angiotensin did not modify ESDs at comparable ESP levels. These findings suggest the existence of a positive inotropic effect mediated by alpha 1 adrenoceptors in the intact human heart.
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Purification and peptidase activity of a bacteriolytic extracellular enzyme from Pseudomonas aeruginosa. Res Microbiol 1989; 140:125-37. [PMID: 2508200 DOI: 10.1016/0923-2508(89)90046-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A bacteriolytic enzyme excreted by Pseudomonas aeruginosa Paks I was purified: samples were found to be homogeneous by gel filtration chromatography, ion exchange chromatography using CM-cellulose, immunoelectrophoresis, PAGE and SDS-PAGE. The molecular weight of the lytic enzyme was estimated to be 15,000-19,000. The enzyme was active on Gram-positive bacteria with glycine-containing interpeptide bridges in their murein layers. In addition, this lytic enzyme showed peptidase activity catalysing the hydrolysis of pentaglycine peptides into tri- and diglycine peptides.
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[Intravenous regional anesthesia with lidocaine. Histological aspects of the venous system. Clinical and experimental study]. Braz J Anesthesiol 1969; 19:558-61. [PMID: 5406151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
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