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McCord M, Fierman A, Sisco S, Canfield C, Manjunath S, Cohen N, Havens J, Wilcox W, Tomopoulos S, Albert MS, Abraham T, Charney A, Acri M, Piwnica-Worms K. A Two-Generation, Early Childhood Advanced Primary Care Model. Pediatrics 2024; 153:e2023062567. [PMID: 38444349 DOI: 10.1542/peds.2023-062567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/13/2023] [Indexed: 03/07/2024] Open
Abstract
It is well recognized that early experiences produce long-term impacts on health outcomes, yet many children are at risk of not achieving their full potential because of health and service disparities related largely to poverty and racism. Although many pediatric primary care (PPC) models address these needs, most are isolated, add-on efforts that struggle to be scalable and sustainable. We describe 3-2-1 IMPACT (Integrated Model for Parents and Children Together), an initiative to transform the model of PPC delivered within New York City Health + Hospitals, the largest public hospital system in the United States, to address the full range of child and family needs in early childhood. Taking advantage of the frequent contact with PPC in the early years and linking to prenatal services, the model assesses family mental, social, and physical health needs and offers evidence-based parenting supports and integrated mental health services. Launching and sustaining the model in our large health system has required coalition building and sustained advocacy at the state, city, and health system levels. Long-term sustainability of the IMPACT model will depend on the implementation of early childhood-focused advanced payment models, on which we have made substantial progress with our major contracted Medicaid managed care plans. By integrating multiple interventions into PPC and prenatal care across a large public-healthcare system, we hope to synergize evidence-based and evidence-informed interventions that individually have relatively small effect sizes, but combined, could substantially improve child and maternal health outcomes and positively impact health disparities.
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Affiliation(s)
| | - Arthur Fierman
- New York University, Grossman School of Medicine, New York, New York
| | | | - Caitlin Canfield
- New York University, Grossman School of Medicine, New York, New York
| | - Sanjana Manjunath
- New York University, Grossman School of Medicine, New York, New York
| | | | - Jennifer Havens
- New York University, Grossman School of Medicine, New York, New York
| | | | - Suzy Tomopoulos
- New York University, Grossman School of Medicine, New York, New York
| | | | | | | | - Mary Acri
- New York University, Grossman School of Medicine, New York, New York
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Falek I, Acri M, Dominguez J, Havens J, McCord M, Sisco S, Wilcox W, Hoagwood K. Management of depression during the perinatal period: state of the evidence. Int J Ment Health Syst 2022; 16:21. [PMID: 35468808 PMCID: PMC9036756 DOI: 10.1186/s13033-022-00531-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 03/30/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Perinatal depression (PND) is a prevalent ailment that affects both the woman and her family. Addressing PND in primary health care, such as pediatrics and obstetric care settings, has been proposed as an effective way to identify and treat women. OBJECTIVE The purpose of this study is to examine best practices for management of PND in obstetric and pediatric settings, as well as investigate the evidence that supports the guidelines. METHODS Guidelines were identified through a literature search and discussion with experts in the field of perinatal depression, while evidence was examined through a literature search of reviews and thereafter experimental studies. RESULTS Twenty-five guidelines, across 17 organizations were retained for analysis. Findings suggest that there is little or varied guidance on the management of PND, as well as a lack of specificity. Treatment was the topic most frequently reported, followed by screening. However best practices vary greatly and often contradict one another. Across all areas, there is inadequate or contrasting evidence to support these guidelines. CONCLUSIONS Although there was consensus on the key steps in the pathway to care, the review revealed lack of consensus across guidelines on specific issues relating to identification and management of depression during the perinatal period. Clinicians may use these recommendations to guide their practice, but they should be aware of the limitations of the evidence supporting these guidelines and remain alert to new evidence. There is a clear need for researchers and policymakers to prioritize this area in order to develop evidence-based guidelines for managing perinatal depression.
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Affiliation(s)
- Idan Falek
- Department of Child & Adolescent Psychiatry, NYU School of Medicine, One Park Avenue, 7th Floor, New York, NY, 10016, USA.
| | - Mary Acri
- Department of Child & Adolescent Psychiatry, NYU School of Medicine, One Park Avenue, 7th Floor, New York, NY, 10016, USA
| | - Joanna Dominguez
- Department of Child & Adolescent Psychiatry, NYU School of Medicine, One Park Avenue, 7th Floor, New York, NY, 10016, USA
| | - Jennifer Havens
- Department of Child & Adolescent Psychiatry, NYU School of Medicine, One Park Avenue, 7th Floor, New York, NY, 10016, USA
| | - Mary McCord
- New York City Health and Hospitals Corporation, 55 Water St., New York, NY, 10041, USA
| | - Sarah Sisco
- New York City Health and Hospitals Corporation, 55 Water St., New York, NY, 10041, USA
| | - Wendy Wilcox
- New York City Health and Hospitals Corporation, 55 Water St., New York, NY, 10041, USA
| | - Kimberly Hoagwood
- Department of Child & Adolescent Psychiatry, NYU School of Medicine, One Park Avenue, 7th Floor, New York, NY, 10016, USA
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Wilcox W, Bajaj K, Rossberg MC, Knight C, Wieland D, Malhotra Y. Lessons learnt in transitioning from universal screening to universal testing of pregnant patients for SARS-CoV-2 at the largest municipal health system in America. J Perinatol 2021; 41:1174-1176. [PMID: 33462340 PMCID: PMC7812978 DOI: 10.1038/s41372-020-00889-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 09/22/2020] [Accepted: 11/20/2020] [Indexed: 11/27/2022]
Affiliation(s)
- Wendy Wilcox
- NYC Health + Hospitals/Kings County, Brooklyn, NY, USA.
| | - Komal Bajaj
- grid.422616.50000 0004 0443 7226NYC Health + Hospitals/Jacobi, Bronx, NY USA
| | - Max C. Rossberg
- grid.251993.50000000121791997Albert Einstein College of Medicine, Bronx, NY USA
| | - Clementine Knight
- grid.251993.50000000121791997Albert Einstein College of Medicine, Bronx, NY USA
| | - Daryl Wieland
- grid.422616.50000 0004 0443 7226NYC Health + Hospitals/Jacobi, Bronx, NY USA
| | - Yogangi Malhotra
- grid.422616.50000 0004 0443 7226NYC Health + Hospitals/Jacobi, Bronx, NY USA
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Malhotra Y, Miller R, Bajaj K, Sloma A, Wieland D, Wilcox W. No change in cesarean section rate during COVID-19 pandemic in New York City. Eur J Obstet Gynecol Reprod Biol 2020; 253:328-329. [PMID: 32620511 PMCID: PMC7287463 DOI: 10.1016/j.ejogrb.2020.06.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 06/06/2020] [Indexed: 12/01/2022]
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Germain D, Giugliani R, Bichet D, Wilcox W, Hugues D, Amartino H, Schiffmann R, Viereck C, Skuban N, Castelli J, Barth J. Effet du migalastat sur une cohorte d’hommes atteints d’une forme classique de la maladie de Fabry issue de l’étude de phase III, FACETS. Nephrol Ther 2017. [DOI: 10.1016/j.nephro.2017.08.275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Germain D, Hugues D, Bichet D, Schiffmann R, Wilcox W, Holdbrook F, Viereck C, Yu J, Skuban N, Castelli J, Barth J. Effet du migalastat sur les critères combinés de l’accumulation rénale du globotriaosylcéramide et des diarrhées chez les patients atteints d’une maladie de Fabry : résultats issus de l’étude de phase III FACETS. Nephrol Ther 2017. [DOI: 10.1016/j.nephro.2017.08.274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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King M, Ragsdale E, Ferreira JC, McKenzie T, Karpel B, Choi Y, Papera S, Moore R, Wilcox W, Gross S. 282: Adoption of evidence based recommendations for GDM results in improved fetal and maternal outcomes. Am J Obstet Gynecol 2013. [DOI: 10.1016/j.ajog.2012.10.447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Gennaro S, Fantasia HC, Keshinover T, Garry D, Wilcox W, Uppal E. Racial and ethnic identity in nursing research. Nurs Outlook 2012; 61:174-80. [PMID: 22975139 DOI: 10.1016/j.outlook.2012.07.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2011] [Revised: 07/04/2012] [Accepted: 07/11/2012] [Indexed: 11/19/2022]
Abstract
Nurse researchers need to be able to identify the race and ethnicity of participants in their studies for several reasons including addressing health disparities, ensuring adequate representation from under-represented minorities, and making sure other nurses can understand how findings may or may not pertain to their own patient population. However, obtaining accurate information about race and ethnicity requires careful attention to norms of study participants. Race and ethnicity are not always viewed as 2 separate constructs and the definition of both changes over time. In fact, a random sample of 100 patients in 1 hospital found an 11% discrepancy between patients' self-identification of race using 2 different methodologies of self-identification. To optimize accuracy of self-identification of race and ethnicity, this paper discusses techniques learned in practice and in the literature for improving self-identification of these 2 constructs.
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Affiliation(s)
- Susan Gennaro
- William F. Connell School of Nursing Boston College, Chestnut Hill, MA 02467, USA.
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Wolfinger N, Wilcox W, Hernández E. Bendito Amor (‘Blessed Love’): Religion and Relationships among Married and Unmarried Latinos in Urban America. ACTA ACUST UNITED AC 2009. [DOI: 10.18085/llas.3.4.a56194x6p6370713] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Earl D, Kreutzman J, Field F, Krakow D, Wilcox W, Rimoin D, Lachman R, Graham J. 123 LARSEN SYNDROME CLINICAL AND RADIOGRAPHIC DELINEATION. J Investig Med 2004. [DOI: 10.1136/jim-52-suppl1-123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Iughetti P, Alonso LG, Wilcox W, Alonso N, Passos-Bueno MR. Mapping of the autosomal recessive (AR) craniometaphyseal dysplasia locus to chromosome region 6q21-22 and confirmation of genetic heterogeneity for mild AR spondylocostal dysplasia. Am J Med Genet 2000; 95:482-91. [PMID: 11146471 DOI: 10.1002/1096-8628(20001218)95:5<482::aid-ajmg14>3.0.co;2-x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We report on a four-generation inbred family including 10 individuals affected with a form of craniotubular dysplasia (CTD). All affected patients were born to consanguineous healthy parents; this finding, together with the equal sex ratio among affected individuals and the occurrence of only normal individuals among their offspring, indicates that the disease in this family is an autosomal recessive (AR) trait. Taking into account the segregation pattern of the disease in the family and the radiological characteristics of two young CTD patients, the most likely diagnosis for the defect is AR craniometaphyseal dysplasia (CMD). CMD is a CTD, with both autosomal dominant (AD) and recessive forms. The description of the present genealogy confirms the AR pattern of inheritance of some cases of CMD and contributes to a better delineation of the clinical spectrum of AR CMD, suggesting a more pronounced diaphyseal involvement in the AR compared with the AD CMD. Through genomewide scanning, we mapped the AR CMD to a 7 cM interval, between D6S302 and D6S1639, at 6q21-22 region. We have also excluded the positional candidate COL10A1 gene as being the responsible for this disorder. Curiously, a form of AR spondylocostal dysplasia (SD) also segregates in the family, including one affected individual with both conditions. The gene DLL3, mapped to 19q13 region, was recently found to be responsible for one form of AR SD; however, we did not find evidence of linkage between this 19q region and the SD segregating in our family, thus implying in genetic heterogeneity for AR SD.
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Affiliation(s)
- P Iughetti
- Departamento de Biologia, Departamento de Biologia, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
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Colige A, Sieron AL, Li SW, Schwarze U, Petty E, Wertelecki W, Wilcox W, Krakow D, Cohn DH, Reardon W, Byers PH, Lapière CM, Prockop DJ, Nusgens BV. Human Ehlers-Danlos syndrome type VII C and bovine dermatosparaxis are caused by mutations in the procollagen I N-proteinase gene. Am J Hum Genet 1999; 65:308-17. [PMID: 10417273 PMCID: PMC1377929 DOI: 10.1086/302504] [Citation(s) in RCA: 292] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Ehlers-Danlos syndrome (EDS) type VIIC is a recessively inherited connective-tissue disorder, characterized by extreme skin fragility, characteristic facies, joint laxity, droopy skin, umbilical hernia, and blue sclera. Like the animal model dermatosparaxis, EDS type VIIC results from the absence of activity of procollagen I N-proteinase (pNPI), the enzyme that excises the N-propeptide of type I and type II procollagens. The pNPI enzyme is a metalloproteinase containing properdin repeats and a cysteine-rich domain with similarities to the disintegrin domain of reprolysins. We used bovine cDNA to isolate human pNPI. The human enzyme exists in two forms: a long version similar to the bovine enzyme and a short version that contains the Zn++-binding catalytic site but lacks the entire C-terminal domain in which the properdin repeats are located. We have identified the mutations that cause EDS type VIIC in the six known affected human individuals and also in one strain of dermatosparactic calf. Five of the individuals with EDS type VIIC were homozygous for a C-->T transition that results in a premature termination codon, Q225X. Four of these five patients were homozygous at three downstream polymorphic sites. The sixth patient was homozygous for a different transition that results in a premature termination codon, W795X. In the dermatosparactic calf, the mutation is a 17-bp deletion that changes the reading frame of the message. These data provide direct evidence that EDS type VIIC and dermatosparaxis result from mutations in the pNPI gene.
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Affiliation(s)
- A Colige
- Laboratory of Connective Tissues Biology, University of Liège, Liège, Belgium
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Abstract
The tetramerization of melittin, a 26-amino acid peptide from Apis mellifera bee venom, has been studied as a model for protein folding. Melittin converts from a monomeric random coil to an alpha-helical tetramer as the pH is raised from 4.0 to 9.5, as ionic strength is increased, as temperature is raised or lowered from about 37 degrees C, or as phosphate is added. The thermodynamics of this tetramerization (termed "folding") are explored using circular dichroism. The melittin tetramer has two pKa values of 7.5 and 8.5 corresponding to protonation of the N-terminus and Lys 23, respectively. pKa values calculated with the program DelPhi (Gilson, M.K., Sharp, K.A., & Honig, B.H., 1987, J. Comp. Chem. 9, 327-335; Gilson, M.K. & Honig, B.H., 1988a, Proteins 3, 32-52; Gilson, M.K. & Honig, B.H., 1988b, Proteins 4, 7-18) agree with experimental titration data. Greater electrostatic repulsion of these protonated groups destabilizes the tetramer by 3.6 kcal/mol at pH 4.0 compared to pH 9.5. Increasing the concentration of NaCl in the solution from 0 to 0.5 M stabilizes the tetramer by 5-6 kcal/mol at pH 4.0. The effect of NaCl is modeled with a ligand-binding approach. The melittin tetramer is found to have a temperature of maximum stability ranging from 35.5 to 43 degrees C depending on the pH, unfolding above and below that temperature. delta Cp0 for folding ranges from -0.085 to -0.102 cal g-1 K-1, comparable to that of other small globular proteins (Privalov, P.L., 1979, Adv. Protein Chem. 33, 167-241). delta H0 and delta S0 are found to decrease with temperature, presumably due to the hydrophobic effect (Kauzmann, W., 1959, Adv. Protein Chem. 14, 1-63). Phosphate is found to perturb the equilibrium substantially with a maximal effect at 150 mM, stabilizing the tetramer at pH 7.4 and 25 degrees C by 4.6 kcal/mol. The enthalpy change due to addition of phosphate (-7.5 kcal/mol at 25 degrees C) can be accounted for by simple dielectric screening. Both circular dichroism and crystallographic results suggest that phosphate may bind Lys 23 at the ends of the elongated tetramer. These detailed measurements give insight into the relative importance of various forces for the stability of melittin in the folded form and may provide an experimental standard for future tests of computational energetics on this simple protein system.
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Affiliation(s)
- W Wilcox
- Molecular Biology Institute, University of California, Los Angeles 90024
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Abstract
The present report describes our experience with 16 adolescents and young adults with insulin-dependent diabetes mellitus (IDDM; Type I) who switched from two injections of insulin per day to the NovolinPen and four insulin injections a day. Their mean age at the initiation of therapy was 19.2 years with a duration of diabetes of 8.9 years. Sixteen random computer-matched (for age, sex, and duration of diabetes) controls who remained on two insulin injections a day were evaluated for comparison. Most subjects were preparing to leave home for college. After a minimum of 1 year of using the pen, the mean weight gain of the test subjects was significantly greater (P less than .05) than for the computer-matched controls. Glycemic control, as monitored by mean HbA1c values, were similar for the NovolinPen and the control groups (10.8 versus 10.9, respectively) after almost 2 years. The main advantage to the pen expressed by the users was a sense of freedom of lifestyle.
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Affiliation(s)
- H P Chase
- University of Colorado Health Sciences Center, Barbara Davis Center for Childhood Diabetes, Denver, Colorado 80262
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Wilcox W. Current overlap methods in lattice QCD. Phys Rev D Part Fields 1991; 43:2443-2446. [PMID: 10013630 DOI: 10.1103/physrevd.43.2443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Trudinger BJ, Cook CM, Giles WB, Ng S, Fong E, Connelly A, Wilcox W. Fetal umbilical artery velocity waveforms and subsequent neonatal outcome. Br J Obstet Gynaecol 1991; 98:378-84. [PMID: 2031896 DOI: 10.1111/j.1471-0528.1991.tb13428.x] [Citation(s) in RCA: 133] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Flow velocity waveforms (FVWs) from the fetal umbilical artery were recorded from 2178 pregnant women over a 6-year period. All of them had an obstetric factor indicating increased risk of fetal compromise. A total of 6749 studies was recorded. The systolic diastolic (AB) ratio was measured and classified as normal (less than 95th centile), elevated (95-99th centile), high (greater than 99th centile) or extreme (absent diastolic flow). The results of these studies have been related to subsequent fetal and neonatal outcome. An abnormal umbilical artery FVW was associated with shorter gestation and infants with lower birthweight, shorter length and lower ponderal index. There was a highly significant association between an abnormal FVW and the birth of an infant small for gestational age. The significance of the association increased with the increased abnormality of the umbilical artery FVW and this was independent of gestational age. Preterm infants associated with high or extreme AB ratios spent twice as long in the neonatal nursery than those with normal AB ratios. Analysis of 794 pregnancies studies serially indicated that an abnormal FVW in which the AB ratio was increasing, in contrast to a decreasing AB ratio, predicted a poor outcome for both size at birth and duration of neonatal intensive care. We conclude that in high risk pregnancy Doppler umbilical artery FVW studies predict the most compromised fetuses in terms of growth retardation and requirements for neonatal intensive care.
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Affiliation(s)
- B J Trudinger
- Department of Obstetrics and Gynaecology, University of Sydney, Westmead Hospital, Australia
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Woloshyn RM, Draper T, Liu KF, Wilcox W. Lattice heavy-meson decay constants and fermion universality. Phys Rev D Part Fields 1989; 39:978-981. [PMID: 9959726 DOI: 10.1103/physrevd.39.978] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Wilcox W, Woloshyn RM. Erratum: Meson electric form factor on the lattice. Phys Rev D Part Fields 1987; 35:773. [PMID: 9957721 DOI: 10.1103/physrevd.35.773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Wilcox W, Liu KF. Relative charge distributions for quarks in lattice mesons. Phys Rev D Part Fields 1986; 34:3882-3887. [PMID: 9957134 DOI: 10.1103/physrevd.34.3882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Abstract
Twelve- and sixteen-residue peptides have been designed to form tetrameric alpha-helical bundles. Both peptides are capable of folding into amphiphilic alpha-helices, with leucyl residues along one face and glutamyl and lysyl residues along the opposite face. Four such amphiphilic alpha-helices are capable of forming a noncovalently bonded tetramer. Neighboring helices run in antiparallel directions in the design, so that the complex has 222 symmetry. In the designed tetramer, the leucyl side chains interdigitate in the center in a hydrophobic interaction, and charged side chains are exposed to the solvent. The designed 12-mer (ALPHA-1) has been synthesized, and it forms helical aggregates in aqueous solution as judged by circular dichroic spectroscopy. It has also been crystallized and characterized by x-ray diffraction. The crystal symmetry is compatible with (but does not prove) the design. The design can be extended to a four-alpha-helical bundle formed from a single polypeptide by adding three peptide linkers.
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Affiliation(s)
- D Eisenberg
- Molecular Biology Institute, University of California, Los Angeles 90024
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Abstract
The importance of the hydrophobic interaction in stabilizing native protein structure has long been appreciated. However, more than other component forces, this one has resisted quantitative description. We present two approximate methods of assessing the hydrophobic component to the free energy of protein folding. Both are expressed in terms of what can be called hydrophobic moments of the protein. The first method is intended to yield an approximate value for the hydrophobic energy. This energy is calculated from a set of atomic coordinates in terms of the hydrophobicity (or 0th hydrophobic moment) of each amino acid residue and its accessibility or lack of it to aqueous solvent. The second method considers the first moment of the hydrophobicity of a group of residues, the hydrophobic moment. Segments of secondary structure in folded proteins tend to have hydrophobic moments that oppose each other. For example, alpha-helices on the protein surface tend to have one hydrophobic face and one hydrophilic face, with the hydrophilic face out towards the solvent. This pattern of organization is often apparent from a computer model of the protein that shows the magnitude and direction of the hydrophobic moment of each segment of secondary structure. Examples are given for the incorrectly folded structures of Novotný et al [J Mol Biol 177:787, 1984] and for the correct structures to which they correspond.
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Ruddick W, Wilcox W. Operating on the fetus. Hastings Cent Rep 1982; 12:10-4. [PMID: 7174290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Abstract
The specific binding of tritiated ouabain was used to estimate the density of Na+-K+-ATPase sites ("Na+-pump" sites) in segments of skeletal muscle from normal and dystrophic mice. Ouabain binding was approximately 4 times greater in red (soleus) muscle than in white (superficial gastrocnemius) muscle from normal animals. In dystrophic soleus muscles, ouabain binding was decreased by nearly one-half. Because Na+-K+-ATPase activity is associated with plasma membranes, these observations constitute further evidence for a sarcolemmal abnormality in dystrophic mice.
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