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Morrison M, Haber S, Beil H, Giuriceo K, Sapra K. Impacts of Maryland’s Global Budgets on Medicare and Commercial Spending and Utilization. Med Care Res Rev 2020; 78:725-735. [DOI: 10.1177/1077558720954693] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In 2014, Maryland incorporated global budgets into its long-running all-payer rate-setting model for hospitals in order to improve health, increase health care quality, and reduce spending. We used difference-in-differences models to estimate changes in Medicare and commercial insurance utilization and spending in Maryland relative to a hospital-based comparison group. We found slower growth in Medicare hospital spending in Maryland than in the comparison group 4.5 years after model implementation and for commercial plan members after 4 years. We identified reductions in Maryland Medicare admissions but no changes for commercial plan members, although their inpatient spending declined. Relative declines in emergency department and other hospital outpatient spending in Maryland drove slower Medicare hospital spending growth, saving $796 million. Our findings suggest global budgets reduce hospital spending and utilization but aligning incentives between hospital and nonhospital providers may be necessary to further reduce utilization and total spending.
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Affiliation(s)
| | | | - Heather Beil
- RTI International, Research Triangle Park, NC, USA
| | | | - Katherine Sapra
- Centers for Medicare & Medicaid Services, Baltimore, MD, USA
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Perry R, Mittman L, Elkins W, Suvada K, Haber S. What Hospital Implementation Strategies Are Associated with Successful Performance Under Maryland’s All‐Payer Model? Health Serv Res 2020. [DOI: 10.1111/1475-6773.13508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Affiliation(s)
- R. Perry
- RTI International Washington DC United States
| | - L. Mittman
- RTI International Washington DC United States
| | - W. Elkins
- RTI International Research Triangle Park NC United States
| | - K. Suvada
- RTI International Research Triangle Park NC United States
| | - S. Haber
- RTI International Waltham MA United States
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Versace A, Graur S, Greenberg T, Lima Santos JP, Chase HW, Bonar L, Stiffler RS, Hudak R, Kim T, Yendiki A, Greenberg B, Rasmussen S, Liu H, Haber S, Phillips ML. Reduced focal fiber collinearity in the cingulum bundle in adults with obsessive-compulsive disorder. Neuropsychopharmacology 2019; 44:1182-1188. [PMID: 30802896 PMCID: PMC6784994 DOI: 10.1038/s41386-019-0353-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [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: 11/30/2018] [Revised: 01/17/2019] [Accepted: 02/04/2019] [Indexed: 12/31/2022]
Abstract
Obsessive-compulsive disorder (OCD) is a disabling condition, often associated with a chronic course. Given its role in attentional control, decision-making, and emotional regulation, the anterior cingulate cortex is considered to have a key role in the pathophysiology of the disorder. Notably, the cingulum bundle, being the major white matter tract connecting to this region, has been historically a target for the surgical treatment of intractable OCD. In this study, we aimed to identify the extent to which focal-more than diffuse-abnormalities in fiber collinearity of the cingulum bundle could distinguish 48 adults with OCD (mean age [SD] = 23.3 [4.5] years; F/M = 30/18) from 45 age- and sex-matched healthy control adults (CONT; mean age [SD] = 23.2 [3.8] years; F/M = 28/17) and further examine if these abnormalities correlated with symptom severity. Use of tract-profiles rather than a conventional diffusion imaging approach allowed us to characterize white matter microstructural properties along (100 segments), as opposed to averaging these measures across, the entire tract. To account for these 100 different segments of the cingulum bundle, a repeated measures analysis of variance revealed a main effect of group (OCD < CONT; F[1,87] = 5.3; P = 0.024) upon fractional anisotropy (FA, a measure of fiber collinearity and/or white matter integrity), in the cingulum bundle, bilaterally. Further analyses revealed that these abnormalities were focal (middle portion) within the left and right cingulum bundle, although did not correlate with symptom severity in OCD. Findings indicate that focal abnormalities in connectivity between the anterior cingulate cortex and other prefrontal cortical regions may represent neural mechanisms of OCD.
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Affiliation(s)
- A. Versace
- 0000 0004 1936 9000grid.21925.3dDepartment of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh Medical Center, University of Pittsburgh, Pittsburgh, PA USA
| | - S. Graur
- 0000 0004 1936 9000grid.21925.3dDepartment of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh Medical Center, University of Pittsburgh, Pittsburgh, PA USA
| | - T. Greenberg
- 0000 0004 1936 9000grid.21925.3dDepartment of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh Medical Center, University of Pittsburgh, Pittsburgh, PA USA
| | - J. P. Lima Santos
- 0000 0004 1936 9000grid.21925.3dDepartment of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh Medical Center, University of Pittsburgh, Pittsburgh, PA USA
| | - H. W. Chase
- 0000 0004 1936 9000grid.21925.3dDepartment of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh Medical Center, University of Pittsburgh, Pittsburgh, PA USA
| | - L. Bonar
- 0000 0004 1936 9000grid.21925.3dDepartment of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh Medical Center, University of Pittsburgh, Pittsburgh, PA USA
| | - R. S. Stiffler
- 0000 0004 1936 9000grid.21925.3dDepartment of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh Medical Center, University of Pittsburgh, Pittsburgh, PA USA
| | - R. Hudak
- 0000 0004 1936 9000grid.21925.3dDepartment of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh Medical Center, University of Pittsburgh, Pittsburgh, PA USA
| | - Tae Kim
- 0000 0004 1936 9000grid.21925.3dDepartment of Radiology, University of Pittsburgh Medical Center, University of Pittsburgh, Pittsburgh, PA USA
| | - A. Yendiki
- 000000041936754Xgrid.38142.3cAthinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA USA
| | - B. Greenberg
- 0000 0004 0420 4094grid.413904.bDepartment of Psychiatry and Human Behavior, Brown Medical School, Butler Hospital and Providence VA Medical Center, Providence, RI USA
| | - S. Rasmussen
- 0000 0004 0420 4094grid.413904.bDepartment of Psychiatry and Human Behavior, Brown Medical School, Butler Hospital and Providence VA Medical Center, Providence, RI USA
| | - H. Liu
- 000000041936754Xgrid.38142.3cAthinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA USA
| | - S. Haber
- 0000 0004 1936 9166grid.412750.5Department of Pharmacology and Physiology, University of Rochester Medical Center, Rochester, NY 14642 USA
| | - M. L. Phillips
- 0000 0004 1936 9000grid.21925.3dDepartment of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh Medical Center, University of Pittsburgh, Pittsburgh, PA USA
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McDonough I, Haber S, Bischof G, Park D. ENGAGEMENT IN MENTALLY CHALLENGING ACTIVITIES ENHANCES NEURAL EFFICIENCY. Innov Aging 2017. [DOI: 10.1093/geroni/igx004.247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- I. McDonough
- The University of Alabama, Tuscaloosa, Alabama,
- University of Texas at Dallas, Dallas, Texas,
| | - S. Haber
- University of Texas at Dallas, Dallas, Texas,
| | - G.N. Bischof
- University Hospital Cologne International, Cologne, Germany
| | - D.C. Park
- University of Texas at Dallas, Dallas, Texas,
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Affiliation(s)
- G. Hetsroni
- TECHNION–Israel Institute of Technology, Haifa
| | | | - S. Haber
- TECHNION–Israel Institute of Technology, Haifa
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Zheng NT, Haber S, Hoover S, Feng Z. Access to Care for Medicare-Medicaid Dually Eligible Beneficiaries: The Role of State Medicaid Payment Policies. Health Serv Res 2016; 52:2219-2236. [PMID: 27767203 DOI: 10.1111/1475-6773.12591] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
STUDY OBJECTIVES Medicaid programs are not required to pay the full Medicare coinsurance and deductibles for Medicare-Medicaid dually eligible beneficiaries. We examined the association between the percentage of Medicare cost sharing paid by Medicaid and the likelihood that a dually eligible beneficiary used evaluation and management (E&M) services and safety net provider services. DATA SOURCES Medicare and Medicaid Analytic eXtract enrollment and claims data for 2009. STUDY DESIGN Multivariate analyses used fee-for-service dually eligible and Medicare-only beneficiaries in 20 states. A comparison group of Medicare-only beneficiaries controlled for state factors that might influence utilization. PRINCIPAL FINDINGS Paying 100 percent of the Medicare cost sharing compared to 20 percent increased the likelihood (relative to Medicare-only) that a dually eligible beneficiary had any E&M visit by 6.4 percent. This difference in the percentage of cost sharing paid decreased the likelihood of using safety net providers, by 37.7 percent for federally qualified health centers and rural health centers, and by 19.8 percent for hospital outpatient departments. CONCLUSIONS Reimbursing the full Medicare cost-sharing amount would improve access for dually eligible beneficiaries, although the magnitude of the effect will vary by state and type of service.
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Affiliation(s)
- Nan Tracy Zheng
- End-of-Life, Palliative, and Hospice Care, Division for Research on Healthcare Value, Equity, and the Lifespan, RTI International, Waltham, MA
| | - Susan Haber
- Health Coverage for Low-Income and Uninsured Populations, Division for Research on Healthcare Value, Equity, and Lifespan, RTI International, Waltham, MA
| | - Sonja Hoover
- Health Coverage for Low-Income and Uninsured Populations, Division for Research on Healthcare Value, Equity, and Lifespan, RTI International, Waltham, MA
| | - Zhanlian Feng
- Aging, Disability and Long Term Care, Division for Research on Healthcare Value, Equity, and the Lifespan, RTI International, Waltham, MA
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Tangka FKL, Subramanian S, Sabatino SA, Howard DH, Haber S, Hoover S, Richardson LC. End-of-Life Medical Costs of Medicaid Cancer Patients. Health Serv Res 2014; 50:690-709. [PMID: 25424134 DOI: 10.1111/1475-6773.12259] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
OBJECTIVES To quantify end-of-life (EOL) medical costs for adult Medicaid beneficiaries diagnosed with cancer. DATA SOURCES We linked Medicaid administrative data with 2000-2003 cancer registry data to identify 3,512 adult Medicaid beneficiaries who died after a cancer diagnosis and matched them to a cohort of beneficiaries without cancer who died during the same period. STUDY DESIGN We used multivariable regression analysis to estimate incremental per-person EOL cost after controlling for beneficiaries' age, race/ethnicity, sex, cancer site, and state of residence. PRINCIPAL FINDINGS End-of-life costs during the final 4 months of life were about $10,000 higher for Medicaid cancer patients than for those without cancer. Medicaid cancer patients are more intensive users of inpatient and ambulatory services than are Medicaid patients without cancer. Medicaid cancer patients who die soon after diagnosis have higher costs of care and use inpatient services more intensely than do Medicaid patients without cancer. CONCLUSIONS Medicaid cancer patients incur substantially higher EOL costs than noncancer patients. This increased cost may reflect the cost of palliative care. Future studies should assess the types and timing of services provided to Medicaid cancer patients at the EOL.
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Affiliation(s)
- Florence K L Tangka
- Division of Cancer Prevention and Control, CDC, 4770 Buford Highway, NE, MS F-76, Atlanta, GA
| | | | - Susan A Sabatino
- Division of Cancer Prevention and Control, CDC, 4770 Buford Highway, NE, MS F-76, Atlanta, GA
| | - David H Howard
- Rollins School of Public Health, Emory University, Atlanta, GA
| | | | | | - Lisa C Richardson
- Division of Cancer Prevention and Control, CDC, 4770 Buford Highway, NE, MS F-76, Atlanta, GA
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Henry FS, Haber S, Haberthür D, Filipovic N, Milasinovic D, Schittny JC, Tsuda A. The simultaneous role of an alveolus as flow mixer and flow feeder for the deposition of inhaled submicron particles. J Biomech Eng 2014; 134:121001. [PMID: 23363203 DOI: 10.1115/1.4007949] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In an effort to understand the fate of inhaled submicron particles in the small sacs, or alveoli, comprising the gas-exchange region of the lung, we calculated the flow in three-dimensional (3D) rhythmically expanding models of alveolated ducts. Since convection toward the alveolar walls is a precursor to particle deposition, it was the goal of this paper to investigate the streamline maps' dependence upon alveoli location along the acinar tree. On the alveolar midplane, the recirculating flow pattern exhibited closed streamlines with a stagnation saddle point. Off the midplane we found no closed streamlines but nested, funnel-like, spiral, structures (reminiscent of Russian nesting dolls) that were directed towards the expanding walls in inspiration, and away from the contracting walls in expiration. These nested, funnel-like, structures were surrounded by air that flowed into the cavity from the central channel over inspiration and flowed from the cavity to the central channel over expiration. We also found that fluid particle tracks exhibited similar nested funnel-like spiral structures. We conclude that these unique alveolar flow structures may be of importance in enhancing deposition. In addition, due to inertia, the nested, funnel-like, structures change shape and position slightly during a breathing cycle, resulting in flow mixing. Also, each inspiration feeds a fresh supply of particle-laden air from the central channel to the region surrounding the mixing region. Thus, this combination of flow mixer and flow feeder makes each individual alveolus an effective mixing unit, which is likely to play an important role in determining the overall efficiency of convective mixing in the acinus.
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Affiliation(s)
- F S Henry
- Molecular and Integrative Physiological Sciences, Department of Environmental Health, Harvard School of Public Health, Boston, MA 02115, USA
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Seifers DL, Martin TJ, Haber S. Temperature-Sensitive Resistance to Wheat streak mosaic virus in CO960333 and KS06HW79 Wheat. Plant Dis 2013; 97:983-987. [PMID: 30722574 DOI: 10.1094/pdis-10-12-0971-re] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Temperature-sensitive resistance (TSR) that can protect against losses to Wheat streak mosaic virus (WSMV) has been described in elite wheat germplasm. A TSR identified in the advanced breeding line CO960333 and its derivative KS06HW79 was examined in growth-chamber tests conducted under constant temperature regimes of 18, 21, and 24°C against an array of WSMV isolates. At 18°C, all tested isolates systemically infected the pedigree parents, while the progeny line CO960333 remained free of symptoms; at 24°C, all lines were susceptible. At the intermediate temperature of 21°C, the TSR of KS06HW79 was effective in contrast to the TSRs of KS03HW12 and 'RonL'. In field trials conducted in 2011 and 2012, the TSR expressed in KS06HW79 conferred complete protection against yield losses from inoculation with the Sidney 81 isolate of WSMV, while the TSR of RonL conferred similar protection in 2012 but allowed small losses in 2011. The resistance expressed by KS06HW79 is likely not due to the Wsm1 gene because it did not contain the tightly linked J15 sequence-characterized amplified region (SCAR) DNA marker. These findings suggest that KS06HW79 could be an additional TSR source of value to wheat-breeding programs seeking to control losses from WSMV.
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Affiliation(s)
| | - T J Martin
- Professor, Kansas State University Agricultural Research Center-Hays, Hays 67601
| | - S Haber
- Cereal Research Centre, Agriculture & Agri-Food Canada, Winnipeg, MB Canada
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Subramanian S, Tangka FKL, Sabatino SA, Howard D, Richardson LC, Haber S, Halpern MT, Hoover S. Impact of chronic conditions on the cost of cancer care for Medicaid beneficiaries. Medicare Medicaid Res Rev 2013; 2:mmrr2012-002-04-a07. [PMID: 24800160 DOI: 10.5600/mmrr.002.04.a07] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
BACKGROUND No study has assessed the cost of treating adult Medicaid cancer patients with preexisting chronic conditions. This information is essential for understanding the cost of cancer care to the Medicaid program above that expended for other chronic conditions, given the increasing prevalence of chronic conditions among cancer patients. RESEARCH DESIGN We used administrative data from 3 state Medicaid programs' linked cancer registry data to estimate cost of care during the first 6 months following cancer diagnosis for beneficiaries with 4 preexisting chronic conditions: cardiac disease, respiratory diseases, diabetes, and mental health disorders. Our base cohort consisted of 6,212 Medicaid cancer patients aged 21 to 64 years (cancer diagnosed during 2001-2003) who were continuously enrolled in fee-for-service Medicaid for 6 months after diagnosis. A subset of these patients who did not die during the 6-month follow-up (n=4,628), were matched with 2 non-cancer patients each (n=8,536) to assess incremental cost of care. RESULTS The average cost of care for cancer patients with the chronic conditions studied was higher than for cancer patients without any of these conditions. The increase in cancer treatment cost associated with the chronic conditions ranged from $4,385 for cardiac disease to $11,009 for mental health disorders. CONCLUSIONS Chronic conditions, especially the presence of multiple conditions, are associated with a higher cost of care among Medicaid cancer patients, and these increased costs should be reflected in projections of future Medicaid cancer care costs. The implementation of better care-management processes for cancer patients with preexisting chronic conditions may be one way to reduce these costs.
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Affiliation(s)
| | | | | | - David Howard
- Rollins School of Public Health Emory University
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11
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Setter E, Bucher I, Haber S. Low-Reynolds-number swimmer utilizing surface traveling waves: analytical and experimental study. Phys Rev E Stat Nonlin Soft Matter Phys 2012; 85:066304. [PMID: 23005203 DOI: 10.1103/physreve.85.066304] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2011] [Revised: 04/01/2012] [Indexed: 06/01/2023]
Abstract
Microscale slender swimmers are frequently encountered in nature and are now used in microrobotic applications. The swimming mechanism examined in this paper is based on small transverse axisymmetric traveling wave deformations of a cylindrical long shell. The thin-shelled device is assumed to be inextensible at the middle surface and extensible at the surface wetted by the fluid. Assuming low-Reynolds-number hydrodynamics, an analytical solution is derived for waves of small amplitudes compared with the cylinder diameter. We show that swimming velocity increases with β(1) (the ratio of cylinder radius to wavelength) and that swimming velocity is linearly dependent on wave propagation velocity, increasing to leading order with the square of the ratio of wave amplitude to wavelength β(2) and decreasing with the wall thickness. A fourth-order correction in β(2) was also calculated and was found to have a negative effect on the swimming velocity. The results for a shell of negligible-wall thickness were compared with Taylor's solution for an inextensible two-dimensional flat membrane undergoing a waving motion and Felderhof's results [Phys. Fluids 22, 113604 (2010)] for an unbounded flow field and negligible-wall thickness. We show that Taylor's analytic solution is a particular limiting case of the present solution, assuming zero wall thickness and infinite values of β(1). The present mechanism was also compared with Taylor's well known solutions of waving planar and helical circular tails. We show that the present approach yields higher velocities as β(1) increases, whereas, the opposite occurs for waving tails. Indeed, in the region where β(1)>15, the present approach yields velocities nearly as fast as Taylor's helical waving tail while consuming less power and with a design that is considerably more compact. In this regime, the axisymmetric swimmer is twice as fast as Taylor's planar-tail swimmer for an additional investment of only one-third of the power. Experiments were conducted using a macroscale autonomous model immersed in highly viscous silicone fluid. We outlined how the proposed mechanism was realized to propel an elongated, yet finite, swimmer. Measured data demonstrate the effects of wave velocity and wavelength on swimming speed, showing good agreement with analytical results.
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Affiliation(s)
- E Setter
- Faculty of Mechanical Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel
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12
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Walsh EG, Wiener JM, Haber S, Bragg A, Freiman M, Ouslander JG. Potentially avoidable hospitalizations of dually eligible Medicare and Medicaid beneficiaries from nursing facility and Home- and Community-Based Services waiver programs. J Am Geriatr Soc 2012; 60:821-9. [PMID: 22458363 DOI: 10.1111/j.1532-5415.2012.03920.x] [Citation(s) in RCA: 150] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVES Beneficiaries dually eligible for Medicare and Medicaid are of increasing interest because of their clinical complexity and high costs. The objective of this study was to examine the incidence, costs, and factors associated with potentially avoidable hospitalizations (PAH) in this population. DESIGN Retrospective study of hospitalizations. SETTING Hospitalizations from nursing facilities (NF) including Medicare and Medicaid-covered stays, and Medicaid Home and Community-Based Services (HCBS) waiver programs. PARTICIPANTS Dually eligible individuals who received Medicare skilled nursing facility (SNF) or Medicaid NF services or HCBS waiver services in 2005. INTERVENTIONS None. MEASUREMENTS Potentially avoidable hospitalizations were defined by an expert panel that identified conditions and associated Diagnostic Related Groups (DRGs) which can often be prevented or safely and effectively managed without hospitalization. RESULTS More than one-third of the population was hospitalized at least once, totaling almost 1 million hospitalizations. The admitting DRG for 382,846 (39%) admissions were identified as PAH. PAH rates varied considerably among states, and blacks had a higher rate and costs for PAH than whites. Five conditions (pneumonia, congestive heart failure, urinary tract infections, dehydration, and chronic obstructive pulmonary disease/asthma) were responsible for 78% of the PAH. The total Medicare costs for these hospitalizations were $3 billion, but only $463 million for Medicaid. A sensitivity analysis, assuming that 20%-60% of these hospitalizations could be prevented, revealed that between 77,000 and 260,000 hospitalizations and between $625 million and $1.9 billion in expenditures could be avoided annually in this population. CONCLUSION Potentially avoidable hospitalizations are common and costly in the dually eligible population. New initiatives are needed to reduce PAH in this population as they are costly and can adversely affect function and quality of life.
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Affiliation(s)
- Edith G Walsh
- Department of Aging, Disability and Long Term Care, RTI International, Waltham, Massachusetts, USA
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13
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Riley ED, Moore KL, Haber S, Neilands TB, Cohen J, Kral AH. Population-level effects of uninterrupted health insurance on services use among HIV-positive unstably housed adults. AIDS Care 2011; 23:822-30. [PMID: 21400308 DOI: 10.1080/09540121.2010.538660] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Health services research consistently confirms the benefit of insurance coverage on the use of health services sought in the USA. However, few studies have simultaneously addressed the multitude of competing and unmet needs specifically among unstably housed persons. Moreover, few have accounted for the fact that hospitalization may lead to obtaining insurance coverage, rather than the other way around. This study used marginal structural models to determine the longitudinal impact of insurance coverage on the use of health services and antiretroviral therapy (ART) among HIV-positive unstably housed adults. The impact of insurance status on the use of health services and ART was adjusted for a broad range of confounders specific to this population. Among 330 HIV-positive study participants, both intermittent and continuous insurance coverage during the prior 3-12 months had strong and positive effects on the use of ambulatory care and ART, with stronger associations for continuous insurance coverage. Longer durations of continuous coverage were less robust in affecting emergency and inpatient care. Race and ethnicity had no significant influence on health services use in this low-income population when confounding due to competing needs was considered in adjusted analyses. Given that ambulatory care and ART are factors with substantial potential impact on the course of HIV disease, these data suggest that securing uninterrupted insurance coverage would result in large reductions in morbidity and mortality. Health care policy efforts aimed at increasing consistent insurance coverage in vulnerable populations are warranted.
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Affiliation(s)
- Elise D Riley
- Department of Medicine, University of California, San Francisco, USA.
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14
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Ikegami M, Haber S, Goodman RM. Isolation and characterization of virus-specific double-stranded DNA from tissues infected by bean golden mosaic virus. Proc Natl Acad Sci U S A 2010; 78:4102-6. [PMID: 16593050 PMCID: PMC319734 DOI: 10.1073/pnas.78.7.4102] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A double-stranded (ds) DNA which may be a replication intermediate was isolated from bean (Phaseolus vulgaris L. "Top Crop") leaves systemically infected with bean golden mosaic virus, a whitefly-transmitted plant virus with a genome of circular single-stranded (ss) DNA. The isolation method used phenol/chloroform extraction, hydroxyapatite column chromatography, and rate-zonal centrifugation. The dsDNA had sequences complementary to those of viral DNA. The guanine-plus-cytosine content was 35%, and the sedimentation coefficient in alkaline sucrose density gradients was similar to that of viral ssDNA. Digestion of the dsDNA by Hha I endonuclease produced fragments that corresponded exactly in number and size with those produced by complete digestion of circular viral ssDNA by Hha I, when the fragments were denatured and analyzed on polyacrylamide gels. The dsDNA molecule was a circular structure with one discontinuity in one strand; hybridization results suggest that some of a the dsDNA has a discontinuity in the viral strand and some has a discontinuity in the nonviral strand. On the basis of these structures for the dsDNA, a preliminary model for replication of viral DNA is discussed.
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Affiliation(s)
- M Ikegami
- Department of Plant Pathology, University of Illinois, Urbana, Illinois 61801
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Seifers DL, Martin TJ, Harvey TL, Haber S, Krokhin O, Spicer V, Ying S, Standing KG. Identification of Variants of the High Plains virus Infecting Wheat in Kansas. Plant Dis 2009; 93:1265-1274. [PMID: 30759510 DOI: 10.1094/pdis-93-12-1265] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The properties of two virus isolates (U04-82 and U04-83) obtained from two wheat (Triticum aestivum) plants expressing mosaic symptoms were investigated using enzyme-linked immunosorbent assay (ELISA), sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), time-of-flight mass spectrometry (TOFMS), and infection of wheat with resistance to Wheat streak mosaic virus (WSMV). The coat protein mass was estimated by SDS-PAGE as approximately 32 kDa for U04-82 and 30 kDa for U04-83. The amino acid sequence of the coat protein of U04-82 was 99.6 and 85.5% identical to two isolates, ABC58222 and TX96, respectively, of High Plains virus (HPV) described from Texas. U04-82 was transmitted by wheat curl mites and caused significant yield reductions in wheat resistant to WSMV. U04-83 was actually two distinct virus isolates whose capsid protein amino acid sequences were only 57 and 50% similar to that of TX96. Antiserum prepared to a synthetic peptide from the sequence of the U04-83 isolate recognized the two U04-83 isolates, but not the U04-82 isolate.
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Affiliation(s)
- Dallas L Seifers
- Kansas State University, Agricultural Research Center-Hays, Hays, KS 67601-9228
| | - T J Martin
- Kansas State University, Agricultural Research Center-Hays, Hays, KS 67601-9228
| | - Tom L Harvey
- Department of Entomology, Kansas State University, Manhattan, KS 66506
| | - S Haber
- Cereal Research Centre, Agriculture & Agri-Food Canada, Winnipeg, MB, Canada
| | - O Krokhin
- Department of Physics and Astronomy, University of Manitoba, Winnipeg, MB R3T2N2, Canada
| | - V Spicer
- Department of Physics and Astronomy, University of Manitoba, Winnipeg, MB R3T2N2, Canada
| | - S Ying
- Department of Physics and Astronomy, University of Manitoba, Winnipeg, MB R3T2N2, Canada
| | - K G Standing
- Department of Physics and Astronomy, University of Manitoba, Winnipeg, MB R3T2N2, Canada
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Affiliation(s)
- M. Regitz
- a Department of Chemistry , University of Kaiserslautern, Erwin-Schrödinger-Straße , D-6750 , Kaiserslautern , Federal Republic of Germany
| | - S. Haber
- a Department of Chemistry , University of Kaiserslautern, Erwin-Schrödinger-Straße , D-6750 , Kaiserslautern , Federal Republic of Germany
| | - U. Hees
- a Department of Chemistry , University of Kaiserslautern, Erwin-Schrödinger-Straße , D-6750 , Kaiserslautern , Federal Republic of Germany
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Filipovic N, Ravnic D, Kojic M, Mentzer S, Haber S, Tsuda A. Interactions of blood cell constituents: Experimental investigation and computational modeling by discrete particle dynamics algorithm. Microvasc Res 2008; 75:279-84. [DOI: 10.1016/j.mvr.2007.09.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2006] [Revised: 09/24/2007] [Accepted: 09/30/2007] [Indexed: 10/22/2022]
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Seifers DL, Martin TJ, Harvey TL, Haber S. Temperature-Sensitive Wheat streak mosaic virus Resistance Identified in KS03HW12 Wheat. Plant Dis 2007; 91:1029-1033. [PMID: 30780438 DOI: 10.1094/pdis-91-8-1029] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Wheat streak mosaic virus (WSMV) infection reduces seed yield and quality in wheat. These losses can be alleviated significantly by exploiting genetic host plant resistance. A new source of temperature-sensitive resistance to WSMV, KS03HW12, and its parental lines (KS97HW29/ KS97HW131//KS96HW100-5) were evaluated in both greenhouse and field conditions. Parental wheat lines were exposed to WSMV pressure under different temperatures in growth chambers to determine the stability of the resistance, and 2 years of field yield trials were conducted to confirm effectiveness. To determine the effectiveness of its resistance against a spectrum of isolates, KS03HW12 was tested against six different WSMV isolates of different geographic origins. Among the three pedigree parents, only one, KS97HW29, was resistant. The parental lines of KS97HW29 are not available for testing; therefore, the presumed origin of the resistance could not be further confirmed. None of the six tested WSMV isolates systemically infected KS03HW12 at 18°C. Yield of KS03HW12 in field tests was not different from healthy controls. Thus, the elite winter wheat KS03HW12 appears to be a stable and effective source of temperature-sensitive resistance to WSMV and should be useful for wheat breeding programs.
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Affiliation(s)
| | - T J Martin
- Professor, Kansas State University Agricultural Research Center-Hays, Hays 67601
| | - T L Harvey
- Professor, Department of Entomology, Kansas State University, Manhattan 66506
| | - S Haber
- Cereal Research Center, Agriculture & Agri-Food Canada, Winnipeg, Canada
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Gilman BH, Gage B, Haber S, Hoover S, Aggarwal J. Impact of drug coverage on medical expenditures among the elderly. Health Care Financ Rev 2007; 29:103-18. [PMID: 18624083 PMCID: PMC4195011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Our study compares expenditures for Medicare covered medical services among enrollees in three State pharmacy assistance programs with spending among low-income residents eligible or near-eligible for, but not enrolled in such State-sponsored programs after controlling for between-group differences in demographic, socioeconomic, health status, and insurance status characteristics. We estimate a two-part model in total and by type of service (inpatient, outpatient, and professional) and chronic condition (hypertension, heart disease, and arthritis). We find that drug coverage has no discernible effect on the use and cost of inpatient services, but is associated with a statistically significant increase in Medicare spending for physician services.
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Haber S, Filipovic N, Kojic M, Tsuda A. Dissipative particle dynamics simulation of flow generated by two rotating concentric cylinders: boundary conditions. Phys Rev E Stat Nonlin Soft Matter Phys 2006; 74:046701. [PMID: 17155206 DOI: 10.1103/physreve.74.046701] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2005] [Revised: 07/19/2006] [Indexed: 05/12/2023]
Abstract
The dissipative particle dynamics (DPD) method was used to simulate the flow in a system comprised of a fluid occupying the space between two cylinders rotating with equal angular velocities. The fluid, initially at rest, ultimately reaches a steady, linear velocity distribution (a rigid-body rotation). Since the induced flow field is solely associated with the no-slip boundary condition at the walls, we employed this system as a benchmark to examine the effect of bounce-back reflections, specular reflections, and Pivkin-Karniadakis no-slip boundary conditions, upon the steady-state velocity, density, and temperature distributions. An additional advantage of the foregoing system is that the fluid occupies inherently a finite bounded domain so that the results are affected by the prescribed no-slip boundary conditions only. Past benchmark systems such as Couette flow between two infinite parallel plates or Poiseuille flow in an infinitely long cylinder must employ artificial periodic boundary conditions at arbitrary upstream and downstream locations, a possible source of spurious effects. In addition, the effect of the foregoing boundary conditions on the time evolution of the simulated velocity profile was compared with that of the known, time-dependent analytical solution. It was shown that bounce-back reflection yields the best results for the velocity distributions with small fluctuations in density and temperature at the inner fluid domain and larger deviations near the walls. For the unsteady solutions a good fit is obtained if the DPD friction coefficient is proportional to the kinematic viscosity. Based on dimensional analysis and the numerical results a universal correlation is suggested between the friction coefficient and the kinematic viscosity.
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Affiliation(s)
- S Haber
- Technion-Israel Institute of Technology, Haifa, Israel
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Seifers DL, Martin TJ, Harvey TL, Haber S, Haley SD. Temperature Sensitivity and Efficacy of Wheat streak mosaic virus Resistance Derived from CO960293 Wheat. Plant Dis 2006; 90:623-628. [PMID: 30781139 DOI: 10.1094/pd-90-0623] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Wheat yields often are limited by infection by Wheat streak mosaic virus (WSMV). Host plant resistance to WSMV can reduce losses. This study was conducted to characterize a new source of temperature-sensitive resistance found in CO960293 wheat. The source of the temperature-sensitive resistance in CO960293 is unknown. Parental and other wheat lines were tested for WSMV resistance using 51 WSMV isolates under different temperatures to determine the stability of the resistance, and yield trials were conducted in the field for 3 years. All parental wheat lines became infected by WSMV at all temperatures and were infective in back assay to 'Tomahawk' wheat. No WSMV isolate defeated the resistance of CO960293 at 18°C. Yield of CO960293 in field trials was reduced in only 1 of 3 years. Our data demonstrate that this wheat line can be a valuable source of resistance to WSMV in wheat programs, particularly in areas where temperatures are cool following planting in the fall.
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Affiliation(s)
| | - T J Martin
- Professor, Kansas State University Agricultural Research Center-Hays, Hays 67601
| | - T L Harvey
- Professor, Department of Entomology, Kansas State University, Manhattan 66506
| | - S Haber
- Cereal Research Center, Agriculture & Agri-Food Canada, Winnipeg, Canada
| | - S D Haley
- Soil and Crop Science Department, Colorado State University, Fort Collins 80523
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Barreau B, Tastet S, Picot V, Deghaye M, Brault I, Marelle P, Aucant D, Haber S. Une étude exploratoire des pratiques et des comportements radiologiques devant la découverte d’une anomalie « probablement bénigne » sur la mammographie : à propos de 176 radiologues. ACTA ACUST UNITED AC 2004; 85:1927-36. [PMID: 15602415 DOI: 10.1016/s0221-0363(04)97762-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
OBJECTIVES To evaluate mid-term management of patients with category 3 findings (probably benign, ACR BI-RADS) at mammography three months after a CME course on breast cancer. METHODS A questionnaire (33 items) was sent to 529 radiologists, three months after the CME course (May-December 2002). The answers were analysed using the chi-square test. RESULTS A total of 176 radiologists completed the questionnaire; 63 were part of an organized screening mammography program; 162 used the BI-RADS classification. In the presence of a class 3 finding, 158 radiologists recommended short term follow-up, 28 recommended biopsy, 9 upgraded the level of abnormality, 116 consulted another radiologist, 42 consulted an expert mammographer, 36 submitted the case to a multidisciplinary committee and 12 asked for an overread. Management with short term interval follow-up was worrisome to 91 radiologists for fear of unfavorable outcome, and to 47 radiologists because of possible litigation. Twenty-six radiologists had difficulty explaining to patients the need for short term follow-up. The median score for perceived stress by the radiologists was 3 (0=low and 10=high). CONCLUSION The practices of this sample of French radiologists are consistent with the recommendations presented during the CME course and by the ANAES. They may have some difficulty in communicating with patients the need for follow-up. The ethics of radiology are based on "primum non nocere".
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Affiliation(s)
- B Barreau
- Service de Radiodiagnostic, Institut Bergonié, Centre Régional de Lutte Contre le Cancer, 229, cours de l'Argonne, 33076 Bordeaux Cedex, France.
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Seifers DL, Haber S, Ens W, She YM, Standing KG, Salomon R. Characterization of a distinct Johnsongrass mosaic virus strain isolated from sorghum in Nigeria. Arch Virol 2004; 150:557-76. [PMID: 15503220 DOI: 10.1007/s00705-004-0411-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [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: 06/11/2004] [Accepted: 08/02/2004] [Indexed: 11/26/2022]
Abstract
A virus isolated from sorghum in Nigeria has been partially characterized. It was tested by enzyme-linked immunosorbent assay (ELISA) using antisera to Maize dwarf mosaic virus, Johnsongrass mosaic virus (JGMV), Sugarcane mosaic virus strain-MDB, Sorghum mosaic virus, and Zea mosaic virus. A partial host range, symptom phenotypes for selected sorghum lines, and the mass of the coat protein (CP) subunit was analyzed by sodium-dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), and its amino acid (aa) sequence determined by time-of-flight mass spectrometry (TOFMS). The Nigerian isolate was positive in ELISA to only JGMV antiserum. It infected sorghum and smooth brome but not oat or johnsongrass. It caused necrosis in 12 of 13 tested sorghum lines, while the USA JGMV isolate caused necrosis in only one sorghum line. In SDS-PAGE, the mass of the Nigerian virus CP was 3,000 Da smaller than that of JGMV-MDO. Moreover, TOFMS analyses showed that, while residues 1-7 of the CP aa sequence were identical to those of JGMV (GenBank #A27631), and residues 57-293 were almost identical to residues 67-303 of JGMV, the intermediate region exhibited significant differences, including a 10 aa deletion. These data indicate that the virus should be considered a distinct isolate of JGMV (JGMV-N) and expands the known range of JGMV to Africa.
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Affiliation(s)
- D L Seifers
- Kansas State University, Agricultural Research Center-Hays, 1233 40th Avenue, Hays, KS 67601, USA.
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Seifers DL, She YM, Harvey TL, Martin TJ, Haber S, Ens W, Standing KG, Louie R, Gordon DT. Biological and Molecular Variability Among High Plains virus Isolates. Plant Dis 2004; 88:824-829. [PMID: 30812509 DOI: 10.1094/pdis.2004.88.8.824] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The High Plains virus (HPV), vectored by the wheat curl mite (WCM) (Aceria tosichella), causes a severe disease of maize (Zea mays) in the U. S. High Plains. In the present study, five HPV isolates from five states were separated from co-infecting Wheat streak mosaic virus and their molecular and biological variability studied. Molecular studies involved time-of-flight mass spectrometry (TOFMS) to determine amino acid sequence variability of the 32-kDa nucleoprotein (32 np) of the isolates. Biological studies involved testing the ability of the five HPV isolates to infect a maize line previously shown to have resistance. Inoculations of the HPV isolates were conducted using vascular puncture inoculation (VPI) and viruliferous WCM. TOFMS analyses demonstrated an 18-amino acid sequence in the isolates at the N-terminus of the 32 np, the presence of amino acid sequence differences among the isolates, and variability among amino acid sequences of the 32 np of some isolates. Three of the five HPV isolates infected the resistant maize inbred, B73, using VPI, and two of the same three HPV isolates infected this line using WCM inoculation, albeit low numbers of plants were infected by each technique.
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Affiliation(s)
- Dallas L Seifers
- Professor, Kansas State University, Agricultural Research Center-Hays 67601-9228
| | - Y-M She
- Department of Physics, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Tom L Harvey
- Professor, Department of Entomology, Kansas State University, Manhattan 66506
| | - T J Martin
- Professor, Kansas State University, Agricultural Research Center-Hays
| | - S Haber
- Cereal Research Centre, Agriculture & Agri-Food Canada, Winnipeg, Manitoba, Canada
| | - W Ens
- Department of Physics, University of Manitoba, Winnipeg
| | - K G Standing
- Department of Physics, University of Manitoba, Winnipeg
| | - Raymond Louie
- United States Department of Agriculture-Agricultural Research Service
| | - D T Gordon
- Professor, Emeritus, Department of Plant Pathology, The Ohio State University, Wooster 44691
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Noël A, Heid P, Tardivon A, Dilhuydy MH, Haber S, Séradour B. [Screening mammography of women with a hereditary predisposition to cancer of the breast]. Bull Cancer 2004; 91:655; discussion 656. [PMID: 15381457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Affiliation(s)
- Alain Noël
- Centre Alexis Vautrin, Vandoeuvre-lès-Nancy, FRANCE
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Abstract
In a previous simulation, our laboratory demonstrated that the flow induced by a rhythmically expanding and contracting alveolus is highly complex (Haber S, Butler JP, Brenner H, Emanuel I, and Tsuda A, J Fluid Mech 405: 243-268, 2000). Based on these earlier findings, we hypothesize that the trajectories and deposition of aerosols inside the alveoli differ substantially from those previously predicted. To test this hypothesis, trajectories of fine particles (0.5-2.5 microm in diameter) moving in the foregoing alveolar flow field and simultaneously subjected to the gravity field were simulated. The results show that alveolar wall motion is crucial in determining the enhancement of aerosol deposition inside the alveoli. In particular, 0.5- to 1-microm-diameter particles are sensitive to the detailed alveolar flow structure (e.g., recirculating flow), as they undergo gravity-induced convective mixing and deposition. Accordingly, deposition concentrations within each alveolus are nonuniform, with preferentially higher densities near the alveolar entrance ring, consistent with physiological observations. Deposition patterns along the acinar tree are also nonuniform, with higher deposition in the first half of the acinar generations. This is a result of the combined effects of enhanced alveolar deposition in the proximal region of the acinus due to alveoli expansion and contraction and reduction in the number of particles remaining in the gas phase down the acinar tree. We conclude that the cyclically expanding and contracting motion of alveoli plays an important role in determining gravitational deposition in the pulmonary acinus.
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Affiliation(s)
- S Haber
- Department of Mechanical Engineering, Technion, Haifa 32000, Israel.
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Abstract
The thalamus has long been thought to convey subcortical information to the cortex. Indeed, models of basal ganglia function attribute the primary role for the thalamus to a simple relay of information processed in the basal ganglia to the cortex. The thalamic nuclear groups that are associated primarily with this function are the ventral anterior and ventral lateral nuclei and the mediodorsal thalamic nucleus. However, recent studies have shown that the corticothalamic projection is important for the dynamics of the thalamocortical processing. Furthermore, the relay nuclei that carry basal ganglia output to the cortex have recently been shown to project back to the basal ganglia directly. These two recent developments indicate a more dynamic role for the thalamus in basal ganglia information processing than a passive relay.
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Affiliation(s)
- S Haber
- Department of Neurobiology and Anatomy, University of Rochester School of Medicine and Dentistry, New York 14642, USA.
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She YM, Haber S, Seifers DL, Loboda A, Chernushevich I, Perreault H, Ens W, Standing KG. Determination of the complete amino acid sequence for the coat protein of brome mosaic virus by time-of-flight mass spectrometry. Evidence for mutations associated with change of propagation host. J Biol Chem 2001; 276:20039-47. [PMID: 11274180 DOI: 10.1074/jbc.m100189200] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [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] [Indexed: 11/06/2022] Open
Abstract
Time-of-flight mass spectrometry (TOFMS) has been applied to determine the complete coat protein amino acid sequences of a number of distinct brome mosaic virus (BMV) isolates. Ionization was carried out by both electrospray ionization and matrix-assisted laser desorption/ionization (MALDI). After determining overall coat protein masses, the proteins were digested with trypsin or Lys-C proteinases, and the digestion products were analyzed in a MALDI QqTOF mass spectrometer. The N terminus of the coat protein was found to be acetylated in each BMV isolate analyzed. In one isolate (BMV-Valverde), the amino acid sequence was identical to that predicted from the cDNA sequence of the "type" isolate, but deviations from the predicted amino acid sequence were observed for all the other isolates analyzed. When isolates were propagated in different host taxa, modified coat protein sequences were observed in some cases, along with the original sequence. Sequencing by TOFMS may therefore provide a basis for monitoring the effects of host passaging on a virus at the molecular level. Such TOFMS-based analyses assess the complete profiles of coat protein sequences actually present in infected tissues. They are therefore not subject to the selection biases inherent in deducing such sequences from reverse-transcribed viral RNA and cloning the resulting cDNA.
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Affiliation(s)
- Y M She
- Department of Physics & Astronomy, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
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Lapidot A, Haber S. Effect of endogenous beta-hydroxybutyrate on glucose metabolism in the diabetic rabbit brain: a (13)C-magnetic resonance spectroscopy study of [U-(13)C]glucose metabolites. J Neurosci Res 2001; 64:207-16. [PMID: 11288149 DOI: 10.1002/jnr.1067] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The neurological consequences of diabetes mellitus have recently been receiving greater attention in both clinical and experimental settings. The deleterious effect of hyperglycemia and altered oxidative substrate availability on the diabetic brain is the subject of many studies. The aim of the present study was to examine the effect of the altered metabolic environment, namely, hyperglycemia and hyperketonemia, on glucose metabolism in the diabetic brain. More specifically, we examined the effect of diabetes on the glucose flux via the pyruvate dehydrogenase (PDH) and pyruvate carboxylase (PC) pathways and subsequent metabolism in the tricarboxylic acid cycles in neurons and glia. To this end, [U-(13)C]glucose was infused into the circulation of alloxan-induced diabetic young adult rabbits, and the [(13)C]glucose metabolites were subsequently studied in brain extracts by (13)C-NMR. Significantly elevated brain glucose levels were found. In the hyperketonemic rabbits, elevated cerebral levels of beta-hydroxybutyrate (beta-HBA) were found. Alterations in the labeling patterns of glutamine in the hyperketonemic group lead to the conclusion that the elevated beta-HBA levels inhibit glucose metabolism, mostly in glia. This results in accumulation of glucose in the diabetic brain. In addition, altered levels of glutamine, glutamate, and GABA were also attributed to the effect of beta-HBA on brain metabolism. The possible role of these metabolic perturbations in causing neurological damage remains to be investigated.
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Affiliation(s)
- A Lapidot
- Department of Organic Chemistry, Weizmann Institute of Science, Rehovot, Israel.
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Abstract
The principle substrate for brain metabolism is glucose, which provides both energy and the carbon skeletons of glutamate and glutamine, via the TCA cycle. The existence of two distinct cerebral metabolic compartments, neurons and glia, involved in glutamate and glutamine synthesis, respectively, is a widely accepted concept. In previous work, the relative glucose flux via pyruvate dehydrogenase (PDH) and pyruvate carboxylase (PC) in adult rabbit brain, using 13C NMR isotopomer analysis of glutamate and glutamine, was quantified. In this work, manifestation of cerebral compartmentation in the near-term fetal rabbit was investigated, using the above approach. Following infusion of [U-13C]glucose into maternal circulation (1 mg/kg per min) for 60-70 min, fetal brains were excised and brain extracts were studied by 13C NMR. The labelling patterns of fetal cerebral metabolites differed from those observed in the young adult brain. The most significant differences were found for glutamine labelling patterns. We suggested that these differences are a result of increased utilization of non-labeled fuels, mainly beta-hydroxybutyrate (beta-HBA) in the glia, the site of glutamine synthesis. In addition, we have shown that acute exposure to elevated beta-HBA levels leads to increased uptake, but not utilization, into the fetal rabbit brain; no increase in uptake is observed in the adult brain. We have also demonstrated that during short-term starvation, although no changes are detected in plasma and cerebral glucose levels in the fetal and young adult brain, amino acid levels and energy metabolism are altered in the young adult brain.
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Affiliation(s)
- S Haber
- Department of Organic Chemistry, Weizmann Institute of Science, 76 100, Rehovot, Israel
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Puech F, Vallee BB, Blondel B, Caporossi L, Collet M, Derrien J, Desroches A, Droulle P, Fermont L, Fredouille C, Haber S, Leyronas A, Matuchansky C, Nisand I, Pankert N, Peresse G, Talmant C, Moquet MJ. [Obstetrical ultrasonography during pregnancy without risk factors]. Gynecol Obstet Fertil 2001; 29:159-60. [PMID: 11320985 DOI: 10.1016/s1297-9589(00)00065-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Lapidot A, Haber S. Effect of acute insulin-induced hypoglycemia on fetal versus adult brain fuel utilization, assessed by (13)C MRS isotopomer analysis of [U-(13)C]glucose metabolites. Dev Neurosci 2000; 22:444-55. [PMID: 11111161 DOI: 10.1159/000017474] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Tight glycemic control during diabetic pregnancy has been shown to significantly reduce the occurrence of congenital malformations and other effects of maternal diabetes on the offspring. However, intensive insulin therapy often causes recurring acute maternal hypoglycemia, which has been found to be harmful to the developing fetus, although the mechanisms involved are not clear. The aim of our work was to study the effect of acute insulin-induced maternal hypoglycemia on glucose metabolism in the fetal brain. To this end, near-term pregnant New Zealand rabbits were rendered hypoglycemic, and [U-(13)C]glucose was infused into maternal circulation. The metabolic fate of the (13)C-labeled glucose was then studied in fetal brain extracts by (13)C NMR isotopomer analysis, together with conventional biochemical assays of glucose and lactate levels in both plasma and brain. For comparison [U-(13)C]glucose was also administered to insulin-induced hypoglycemic young adult rabbits. Our results showed that while plasma glucose levels were significantly reduced (approximately 70%) relative to controls, no changes in cerebral glucose levels could be detected. Lactate levels were found to be significantly decreased in hypoglycemic fetal plasma and brain. No differences in lactate levels between control and hypoglycemic young rabbit plasma and brain were observed. These differences were attributed to the utilization of lactate as an energy substrate in the fetal brain, but not in the adult brain. Higher relative (13)C enrichments of most glucose metabolites, except lactate, in the hypoglycemic fetal and young rabbit brains, observed by (13)C NMR, stem from reduced endogenous plasma glucose pools, thereby diluting the labeled glucose to a lower extent. The relative glucose (or glucose-derived lactate) flux via the pyruvate carboxylase and pyruvate dehydrogenase pathways (PC/PDH ratio) was not altered under hypoglycemic conditions in the fetal brain for both glutamine and glutamate, but significantly increased in the adult brain for both glutamine and glutamate. The presented data indicate the ability of the fetal brain to maintain energy metabolism during acute hypoglycemia, via lactate utilization. The increase in the adult PC/PDH ratio was suggested by us to stem from increased PC activity, in order to replenish TCA cycle intermediates.
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Affiliation(s)
- A Lapidot
- Department of Organic Chemistry, Weizmann Institute of Science, Rehovot, Israel.
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Seifers DL, Salomon R, Marie-Jeanne V, Alliot B, Signoret P, Haber S, Loboda A, Ens W, She YM, Standing KG. Characterization of a novel potyvirus isolated from maize in Israel. Phytopathology 2000; 90:505-13. [PMID: 18944557 DOI: 10.1094/phyto.2000.90.5.505] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
A potyvirus (proposed name of Zea mosaic virus [ZeMV]) isolated from maize in Israel was analyzed by serology, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of capsid proteins, symptomatology, and sequencing. Parts of the nuclear inclusion b, coat protein, and 3' regions were sequenced; the amino acid sequence of ZeMV capsid was determined by time-of-flight mass spectrometry (TOFMS). The results of these analyses were compared with those of similar analyses of the following potyviruses: Maize dwarf mosaic virus (MDMV), Sugarcane mosaic virus strain MDB (SCMV-MDB), Johnsongrass mosaic virus(JGMV), Sorghum mosaic virus (SrMV), and an isolate of MDMV from Israel. Indirect enzyme-linked immunosorbent assay using ZeMV antiserum detected only ZeMV, and reciprocal tests using MDMV, JGMV, or SrMV antisera failed to detect ZeMV. ZeMV cross-reacted weakly when SCMV-MDB antiserum was used. The mass of ZeMV capsid was determined to be 36,810 Da by SDS-PAGE and 34,216 Da by TOFMS. The ZeMV systemically infected johnsongrass (Sorghum halepense), but did not infect oat (Avena sativa), pearl millet (Pennisetum glaucum), barley (Hordeum vulgare), or rye (Secale cereale). Necrosis was caused in 19 sorghum lines by SrMV, in 15 by ZeMV, in 14 by MDMV, and in 5 by JGMV and SCMV-MDB. The nucleic acid and amino acid sequences of ZeMV clearly showed that it is not a strain of JGMV, MDMV, SCMV, or SrMV.
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Abstract
The dopamine transporter (DAT) was localized in normal human brain tissue by light microscopic immunocytochemistry by using highly specific monoclonal antibodies. Regional distribution of DAT was found in areas with established dopaminergic circuitry, e.g., mesostriatal, mesolimbic, and mesocortical pathways. Mesencephalic DAT-immunoreactivity was enriched in the dendrites and cell bodies of neurons in the substantia nigra pars compacta and ventral tegmental area. Staining in the striatum and nucleus accumbens was dense and heterogeneous. Mesocortical DAT immunoreactivity in motor, premotor, anterior cingulate, prefrontal, entorhinal/perirhinal, insular, and visual cortices was detected in scattered varicose and a few nonvaricose fibers. Varicose fibers were relatively enriched in the basolateral and central subnuclei of amygdala, with sparser fibers in lateral and basomedial subnuclei. Double-labeling studies combining DAT and tyrosine hydroxylase (TH) immunostaining in the ventral mesencephalon showed two subpopulations of dopaminergic neurons differentiated by the presence or absence of DAT-immunoreactivity in the A9 and A10 cell groups. In other dopaminergic cell groups (All, A13-A15), TH-positive hypothalamic neurons showed no detectable DAT-immunoreactivity. However, fine DAT-immunoreactive axons were scattered throughout the hypothalamus, particularly concentrated along the medial border, with more coarse axons present along the lateral border. These findings demonstrate that most mesotelencephalic dopamine neurons of human brain express high levels of DAT throughout their entire somatodendritic and axonal domains, whereas a smaller subpopulation of mesencephalic dopamine cells and all hypothalamic dopamine cell groups examined express little or no DAT. These data indicate that different subpopulations of dopaminergic neurons use different mechanisms to regulate their extracellular dopamine levels.
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Affiliation(s)
- B J Ciliax
- Department of Neurology, Emory University School of Medicine, Atlanta, Georgia 30322, USA.
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Horowitz HW, Kilchevsky E, Haber S, Aguero-Rosenfeld M, Kranwinkel R, James EK, Wong SJ, Chu F, Liveris D, Schwartz I. Perinatal transmission of the agent of human granulocytic ehrlichiosis. N Engl J Med 1998; 339:375-8. [PMID: 9691104 DOI: 10.1056/nejm199808063390604] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- H W Horowitz
- Department of Medicine, Westchester County Medical Center and New York Medical College, Valhalla 10595, USA
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39
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Abstract
PURPOSE To compare the pharmacotherapeutic practices of high-volume photorefractive keratectomy (PRK) surgeons with suggested practices gleaned from the current literature. SETTING York Finch Eye Associates, Toronto, Canada. METHODS Seventy-five ophthalmic surgeons believed by the authors to do a high-volume of PRKs were surveyed over the summer of 1994 about their pharmacotherapeutic practices. The results were compared with suggested practices extracted from a review of the current literature. RESULTS Relatively consistent approaches to the management of post-PRK pain and prevention of acute post-PRK subepithelial infiltrative keratitis were reported. The administration of topical steroids after PRK was almost universally employed. Post-PRK analgesia was most commonly achieved with nonsteroidal anti-inflammatory drugs (NSAIDs) and a soft contact lens, but surgeons were not convinced of the benefits of long-term NSAID administration to control myopic regression and haze. There seemed to be no agreed-on solution to the infrequent problems of severe haze and regression and steroid-induced elevated intraocular pressure after PRK; however, many useful suggestions for the management of these problems were proposed. CONCLUSION In general, high-volume PRK surgeons use topical steroids, NSAIDs, and a soft contact lens in the immediate postoperative period, although they are uncertain about the long-term effectiveness of NSAIDs in controlling regression and haze.
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Abstract
Little is known about factors controlling the dynamics of aerosol dispersion and deposition in the lung periphery, though this knowledge becomes increasingly important in many fields such as environmental and occupational exposure, diagnostic applications, and therapeutic deliver of drugs via aerosols. For the last several years, we have been studying aerosol behavior in the pulmonary acinus, where the airway structure and the associated fluid mechanics are distinctly different from those in the conducting airways. Our major research efforts have been focused on the basic physics underlying acinar fluid mechanics and particle dynamics, which are likely to be conditioned by the two key geometric factors of acinar airways: structural alveolation and rhythmic expansion and contraction of the alveolar walls. A combination of computational and experimental analyses revealed that due to these unique geometric features acinar flow can be extremely complex despite the low Reynolds number, and can have substantial effects on particle dynamics. In particular, chaotic mixing can occur in the lung periphery. In the course of such a mixing process, the inhaled aerosol particles quickly mix with the residual alveolar gas in a manner that is radically different from the previously considered classical diffusion process. The objective of this paper is to briefly review our current understanding of these processes, to discuss existing deposition models, and to describe our ongoing research efforts toward a basic understanding of aerosol behavior in the pulmonary acinus.
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Affiliation(s)
- A Tsuda
- Physiology Program, Harvard School of Public Health, Boston, Massachusetts, USA
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Affiliation(s)
- L M Sanders
- Department of Radiology, Saint Barnabas Medical Center, Livingston, NJ
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42
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Oberholzer M, Haber S, Zeller P, Baumgartner P, Lips B, Christen H, Mihatsch M, Heitz PU. [Possibilities for the use of administrative electronic data processing in clinical pathology]. Pathologe 1990; 11:229-35. [PMID: 2399216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- M Oberholzer
- Institut für Pathologie, Universität Basel, Schweiz
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43
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Abstract
Modern methods for tracing central nervous system pathways depend largely on active axonal transport mechanisms and are carried out in in vivo animal experiments. This report describes the ability to trace axons and label cell bodies in postmortem human material, using injections of wheat germ agglutinin horseradish peroxidase. Furthermore, it demonstrates the compatibility of this method with immunocytochemical techniques for localizing neurotransmitters. Thus it is possible to study the intrinsic circuitry or short connections in brain regions such as cortex in both normal and pathological material, and, using double label methods, determine the transmitter systems involved. It also raises the issue of the mechanisms which are involved in the movement of the tracer molecule.
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Affiliation(s)
- S Haber
- Department of Neurobiology and Anatomy, University of Rochester School of Medicine and Dentistry, NY 14642
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Haber S, Finklestein SD, Benowitz LI, Collier TJ. Matrigel enhances survival and integration of grafted dopamine neurons into the striatum. Prog Brain Res 1988; 78:427-33. [PMID: 3247441 DOI: 10.1016/s0079-6123(08)60314-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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45
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Haber S. Anatomical relationship between the basal ganglia and the basal nucleus of Meynert in human and monkey forebrain. Proc Natl Acad Sci U S A 1987; 84:1408-12. [PMID: 3469674 PMCID: PMC304439 DOI: 10.1073/pnas.84.5.1408] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Previous immunohistochemical studies have provided evidence that the external segment of the globus pallidus extends ventrally beneath the transverse limb of the anterior commissure into the area of the substantia innominata. Enkephalin-positive staining in the form of "woolly fibers" has been used as a marker for the globus pallidus and its ventral extension. Acetylcholinesterase staining of both fibers and cell bodies, frequently used as a marker for the basal nucleus of Meynert, is also found in the area of the substantia innominata. This study describes the differential distribution of enkephalin-positive woolly fibers and acetylcholinesterase staining on adjacent sections in both the monkey and human basal forebrain area in an attempt to define the relationship between the basal ganglia and the basal nucleus of Meynert. The results show that while both occupy large regions of the basal forebrain, they overlap very little. In both species investigated, dense concentrations of acetylcholinesterase-positive neurons lie, for the most part, outside the boundaries of the pallidal fibers. However, some scattered acetylcholinesterase cells do lie within the confines of the dorsal pallidum, and a more prominent group is found in the subcommissural ventral pallidum. These cells may constitute a group separate from the more densely packed acetylcholinesterase-positive cells in woolly fiber-free regions in that they may receive direct striatal input.
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McCall N, Henton D, Haber S, Paringer L, Crane M, Wrightson W, Freund D. Evaluation of Arizona Health Care Cost Containment System, 1984-85. Health Care Financ Rev 1987; 9:79-89. [PMID: 10312395 PMCID: PMC4192863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
In this article, we describe the evaluation of the Arizona Health Care Cost Containment System (AHCCCS), Arizona's alternative to the acute care portion of Medicaid. We provide an assessment of implementation of the program's innovative features during its second 18 months of operation, from April 1984 through September 1985. Included in the evaluation are assessments of the administration of the program, provider relations, eligibility, enrollment and marketing, information systems, quality assurance and member satisfaction activities, the relationship of the county governments to AHCCCS, the competitive bidding process, and the plans and their financial status.
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Abstract
Fetal substantia nigra cells of two different gestational ages were successfully transplanted into the brains of three methylphenyltetrahydropyridine-treated monkeys with severe parkinsonian motor and behavioural deficits. Functional improvement continued for 10 weeks after cell grafts into the striata of two monkeys with substantial numbers of tyrosine-hydroxylase-positive fetal neurons at necropsy. Behavioural improvement was correlated with increases in cerebrospinal fluid (CSF) homovanillic acid (HVA) concentrations after the transplants. A control monkey with inappropriately placed transplanted cells of an earlier gestational age remained severely parkinsonian and died during a similar period. CSF HVA fell slightly in this monkey from the low level seen before the transplants. Fetal dopamine neurons of two different gestational ages appear to survive transplantation in primates and have biochemical and functional effects.
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Abbas AK, Haber S, Rock KL. Antigen presentation by hapten-specific B lymphocytes. II. Specificity and properties of antigen-presenting B lymphocytes, and function of immunoglobulin receptors. The Journal of Immunology 1985. [DOI: 10.4049/jimmunol.135.3.1661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
The studies described in this paper were designed to examine the ability of hapten-binding murine B lymphocytes to present hapten-protein conjugates to protein antigen-specific, Ia-restricted T cell hybridomas. BALB/c B cells specific for TNP or FITC presented hapten-modified proteins (TNP-G1 phi, TNP-OVA, or FITC-OVA) to the relevant T cell hybridomas at concentrations below 0.1 microgram/ml. Effective presentation of the same antigens by B lymphocyte-depleted splenocytes, and of unmodified proteins by either hapten-binding B cells or Ig spleen cells, required about 10(3)-to 10(4)-fold higher concentrations of antigen. The use of two different haptens and two carrier proteins showed that this extremely efficient presentation of antigen was highly specific, with hapten specificity being a property of the B cells and carrier specificity of the responding T cells. The presentation of hapten-proteins by hapten-binding B lymphocytes was radiosensitive and was not affected by the depletion of plastic-adherent cells, suggesting that conventional APCs (macrophages or dendritic cells) are not required in this phenomenon. Antigen-pulsing and antibody-blocking experiments showed that this hapten-specific antigen presentation required initial binding of antigen to surface Ig receptors. Moreover, linked recognition of hapten and carrier determinants was required, but these recognition events could be temporally separated. Finally, an antigen-processing step was found to be necessary, and this step was disrupted by ionizing radiation. These data suggest a role for B cell surface Ig in providing a specific high-affinity receptor to allow efficient uptake or focusing of antigen for its subsequent processing and presentation to T lymphocytes.
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