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Dive into the research topics where David Loreck is active.

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Featured researches published by David Loreck.


International Journal of Geriatric Psychiatry | 2001

Relationship between aggressive behaviors and depression among nursing home residents with dementia

A. Srikumar Menon; Ann L. Gruber-Baldini; J. Richard Hebel; Bruce Kaup; David Loreck; Sheryl Itkin Zimmerman; Lynda C. Burton; Pearl S. German; Jay Magaziner

Verbal and physical aggression are common behavior problems among nursing home residents with dementia. Depression among nursing home residents is also a common but underdiagnosed disorder.


Metabolic Brain Disease | 1986

Glucose metabolism in human gliomas: Correspondence ofin situ andin vitro metabolic rates and altered energy metabolism

Juan Galarraga; David Loreck; Jon F. Graham; Robert L. DeLaPaz; Barry H. Smith; Douglas Hallgren; C. J. Cummins

The rates of disappearance of glucose from the medium of 13 human glioma-derived cell lines and one cultured of normal human cortical astrocytes were determined by ftuorometric techniques. High-grade glioma-derived cultures showed a range of glucose consumption between 1 and 5 nmol/min/mg protein. Normal astrocyte cultures and cultures derived from grades I–III gliomas had a glucose consumption rate of 2–3 nmol/min/mg protein. Seven high-grade glioma lines were derived from surgical samples taken from patients who had been scanned by18F-2-deoxy-d-glucose positron computed tomography. The rate of glucose consumption in these high-grade glioma-derived lines was close to the maximum local cerebral metabolic rate for glucose (LCMRglc) measuredin situ in the tumors from which the cultures were derived. In cultured glioma-derived lines, approximately one-half of the glucose consumed was recovered as lactate and pyruvate, suggesting a reliance of glioma cells on aerobic glycolysis. ATP and phosphocreatine (PCr) levels were variable in the gliomaderived lines, and ATP was lower in the glioma-derived lines than in the normal astrocytes. Levels and regulation of glycogen differed significantly among the various glioma-derived cell lines. Glycogen content did not diminish as glucose was consumed, suggesting that glycogen utilization is not tightly regulated by the glucose metabolic rate. These results suggest that human glioma-derived cell cultures (1) adequately reflect the metabolic capacity of gliomasin situ and (2) are significantly altered in several aspects of their glycolytic metabolism.


Alzheimers & Dementia | 2014

Vitamin E and memantine in Alzheimer's disease: Clinical trial methods and baseline data

Maurice W. Dysken; Peter Guarino; Julia E. Vertrees; Sanjay Asthana; Mary Sano; Maria Llorente; Muralidhar Pallaki; Susan M. Love; Gerard D. Schellenberg; J. Riley McCarten; Julie Malphurs; Susana Prieto; Peijun Chen; David Loreck; Sara Carney; George Trapp; Rajbir S. Bakshi; Jacobo Mintzer; Judith L. Heidebrink; Ana Vidal-Cardona; Lillian M. Arroyo; Angel R. Cruz; Neil W. Kowall; Mohit P. Chopra; Suzanne Craft; Stephen Thielke; Carolyn Turvey; Catherine Woodman; Kimberly A. Monnell; Kimberly Gordon

Alzheimers disease (AD) has been associated with both oxidative stress and excessive glutamate activity. A clinical trial was designed to compare the effectiveness of (i) alpha‐tocopherol, a vitamin E antioxidant; (ii) memantine (Namenda), an N‐methyl‐D‐aspartate antagonist; (iii) their combination; and (iv) placebo in delaying clinical progression in AD.


American Journal of Geriatric Psychiatry | 2004

Some Predictors of Psychiatric Consultation in Nursing Home Residents

Joanne Fenton; Allen Raskin; Ann L. Gruber-Baldini; A. Srikumar Menon; Sheryl Zimmerman; Bruce Kaup; David Loreck; Paul E. Ruskin; Jay Magaziner

OBJECTIVE Despite the high rate of psychiatric disorders in nursing homes, research indicates that psychiatric consultation is requested infrequently. The authors sought to determine the rate of psychiatric consultation in a nursing home population and to assess what factors were related to a consultation request. METHODS Subjects were recruited from a stratified random sample of 59 nursing homes across Maryland. All new admissions age 65 years and older from September 1992 through March 1995 were eligible for the study. A total of 2,285 subjects were included in the study. Variables examined were factor scores from the Cornell Scale for Depression in Dementia and the Psychogeriatric Dependency Rating Scale (Behavioral Subscale), nursing home characteristics, and whether the resident had a psychiatric consultation within 90 days of admission. RESULTS Twenty percent of the residents (N=404) had a psychiatric consultation. There was no significant association with demographic variables. Behaviors that triggered a psychiatric consultation included agitation, physical/verbal abuse, wandering, and manic/destructive acts. A psychiatric consultation was also requested when residents displayed anxiety. Surprisingly, depression in retarded and psychotic residents did not trigger a psychiatric consult. CONCLUSION As expected, behavioral problems and agitation are common reasons for a psychiatric consultation. However, the resident who is depressed, particularly the quiet or retarded depressed resident, may be overlooked. In this context, it is important for the nursing staff to recognize that lethargy and social withdrawal may be signs of depression, and a referral to a psychiatrist may be in order.


Metabolic Brain Disease | 1987

Regulation of the pentose phosphate pathway in human astrocytes and gliomas

David Loreck; Juan Galarraga; Julie Van der Feen; James M. Phang; Barry H. Smith; C. J. Cummins

Several aspects of the regulation of the pentose phosphate pathway were examined in cultured normal human cortical astrocytes and gliomas of pathological grades I-IV. The generation of radiolabeled CO2 from [l-14C]glucose by the oxidative arm of the pentose phosphate pathway is a saturable process and has a maximum flux rate of 8–9 nmol/hr/mg cell protein. The flux can be blocked by the glycolytic inhibitor iodoacetamide but is unaffected by agents which inhibit oxidative phosphorylation. The magnitude of the pentose phosphate flux is directly related to the glioma grade. Grade IV gliomas (glioblastoma) show a pentose phosphate flux rate of approximately 4% of the total glucose flux. The flux rate can be increased by pharmacological agents which decrease the NADPH/NADP+ ratio. Both the activity and the regulation of glioma glucose-6-phosphate dehydrogenase (G6PDH) are altered in high-grade gliomas. While the affinity constants for cofactors in whole homogenates were not significantly different in glioma or normal astrocyte homogenates, normal astrocytes have a lower Km for glucose-6-phosphate and a G6PDH activity which is 10-fold greater than that of gliomas. NADPH is a powerful regulator of G6PDH activity in the normal astrocytes and in gliomas. At a NADPH/NADP+ ratio of 7:1 the normal astrocyte G6PDH is entirely inhibited, while the glioma enzyme is only 70% inhibited even at a ratio of20: 1. Increased metabolic flux through the oxidative arm of the pentose phosphate pathway is apparently due to an altered form of G6PDH.


Journal of Geriatric Psychiatry and Neurology | 2003

Association of Depression with Agitation in Elderly Nursing Home Residents

Oscar Heeren; Luda Borin; Allen Raskin; Ann L. Gruber-Baldini; A. Srikumar Menon; Bruce Kaup; David Loreck; Paul E. Ruskin; Sheryl Zimmerman; Jay Magaziner

Agitation is a serious problem for elderly individuals with dementia. It is often the major reason for admission to a restrictive environment such as a nursing home or hospital. The objectives of the current study were to (1) identify the components of agitation embedded in the Psychogeriatric Dependency Rating Scale (PGDRS) and (2) find race, gender, depression, and cognitive deficits associated with the factors extracted from the PGDRS in demographic variables and clinical variables. The study sample comprised 2285 subjects who were admitted to 59 nursing homes across Maryland. The factor analysis of the PGDRS confirmed that agitation is made up of a number of different elements ranging from physical and/or verbal aggression to wandering. Correlates of these elements varied, as did possible treatments. For example, physical and/or verbal aggression often accompanied severe depression, suggesting that treating the depression may alleviate this problem. However, wandering and psychotic behavior may be less amenable to existing treatments as these behaviors were associated with severe cognitive impairment. (J Geriatr Psychiatry Neurol 2003; 16:4-7).


JAMA | 2017

Effect of Antidepressant Switching vs Augmentation on Remission Among Patients With Major Depressive Disorder Unresponsive to Antidepressant Treatment: The VAST-D Randomized Clinical Trial

Somaia Mohamed; Gary R. Johnson; Peijun Chen; Paul B. Hicks; Lori L. Davis; Jean Yoon; Theresa C. Gleason; Julia E. Vertrees; Kimberly Weingart; Ilanit Tal; Alexandra Scrymgeour; David Lawrence; Beata Planeta; Michael E. Thase; Grant D. Huang; Sidney Zisook; Sanjai D. Rao; Patricia D. Pilkinton; James Allen Wilcox; Ali Iranmanesh; Mamta Sapra; George Jurjus; James P. Michalets; Muhammed Aslam; Thomas P. Beresford; Keith D. Anderson; Ronald Fernando; Sriram Ramaswamy; John Kasckow; Joseph Westermeyer

Importance Less than one-third of patients with major depressive disorder (MDD) achieve remission with their first antidepressant. Objective To determine the relative effectiveness and safety of 3 common alternate treatments for MDD. Design, Setting, and Participants From December 2012 to May 2015, 1522 patients at 35 US Veterans Health Administration medical centers who were diagnosed with nonpsychotic MDD, unresponsive to at least 1 antidepressant course meeting minimal standards for treatment dose and duration, participated in the study. Patients were randomly assigned (1:1:1) to 1 of 3 treatments and evaluated for up to 36 weeks. Interventions Switch to a different antidepressant, bupropion (switch group, n = 511); augment current treatment with bupropion (augment-bupropion group, n = 506); or augment with an atypical antipsychotic, aripiprazole (augment-aripiprazole group, n = 505) for 12 weeks (acute treatment phase) and up to 36 weeks for longer-term follow-up (continuation phase). Main Outcomes and Measures The primary outcome was remission during the acute treatment phase (16-item Quick Inventory of Depressive Symptomatology-Clinician Rated [QIDS-C16] score ⩽5 at 2 consecutive visits). Secondary outcomes included response (≥50% reduction in QIDS-C16 score or improvement on the Clinical Global Impression Improvement scale), relapse, and adverse effects. Results Among 1522 randomized patients (mean age, 54.4 years; men, 1296 [85.2%]), 1137 (74.7%) completed the acute treatment phase. Remission rates at 12 weeks were 22.3% (n = 114) for the switch group, 26.9% (n = 136)for the augment-bupropion group, and 28.9% (n = 146) for the augment-aripiprazole group. The augment-aripiprazole group exceeded the switch group in remission (relative risk [RR], 1.30 [95% CI, 1.05-1.60]; P = .02), but other remission comparisons were not significant. Response was greater for the augment-aripiprazole group (74.3%) than for either the switch group (62.4%; RR, 1.19 [95% CI, 1.09-1.29]) or the augment-bupropion group (65.6%; RR, 1.13 [95% CI, 1.04-1.23]). No significant treatment differences were observed for relapse. Anxiety was more frequent in the 2 bupropion groups (24.3% in the switch group [n = 124] vs 16.6% in the augment-aripiprazole group [n = 84]; and 22.5% in augment-bupropion group [n = 114]). Adverse effects more frequent in the augment-aripiprazole group included somnolence, akathisia, and weight gain. Conclusions and Relevance Among a predominantly male population with major depressive disorder unresponsive to antidepressant treatment, augmentation with aripiprazole resulted in a statistically significant but only modestly increased likelihood of remission during 12 weeks of treatment compared with switching to bupropion monotherapy. Given the small effect size and adverse effects associated with aripiprazole, further analysis including cost-effectiveness is needed to understand the net utility of this approach. Trial Registration clinicaltrials.gov Identifier: NCT01421342


Anesthesia & Analgesia | 2010

Capacity to Give Surgical Consent Does Not Imply Capacity to Give Anesthesia Consent: Implications for Anesthesiologists

Catherine Marcucci; F. Jacob Seagull; David Loreck; Denis L. Bourke; Neil B. Sandson

There is precedent in medicine for recognizing and accepting intact decisional capacity and the subsequent ability to provide valid consent in one treatment domain, while simultaneously recognizing that the patient lacks decisional capacity in other domains. As such, obtaining consent for anesthesia for a surgical procedure is a separate entity from obtaining consent for the surgery itself. Anesthesia for surgery and the surgical procedure itself are separate treatment domains and as such require separate consents. Anesthesiologists should understand the independence of these functionally linked consent processes and be vigilant with respect to the informed consent process. The cases reported in this article show that capacity for surgical consent may be inadequate for consent to anesthesia because anesthesia involves more abstract concepts requiring a higher cognitive state than surgery, thus requiring a higher state of cognitive capacity for understanding.


Journal of Gerontological Nursing | 2016

Managing Opioid Abuse in Older Adults: Clinical Considerations and Challenges.

David Loreck; Nicole J Brandt; Bethany DiPaula

Opioid use disorder is a public health epidemic. There is increasing attention being given to opioid abuse and overdose in the United States. The overall use of illicit substances by older adults is on the rise and in part can be attributed to the aging of Baby Boomers. Furthermore, much attention is being given to prescription opioid drug overdose, but it is important to note that heroin-related deaths have also increased sharply. Heroin use is part of a larger substance abuse problem, with more than nine in 10 individuals who use heroin also using at least one other drug (e.g., cocaine, prescription opioid medication). The current article highlights treatment approaches, namely buprenorphine, buprenorphine/naloxone, and naltrexone; insurance considerations; and resources to aid in understanding and managing this public health crisis.


American Journal of Alzheimers Disease and Other Dementias | 2017

Elevated Plasma Aβ42 in Cognitively Impaired Individuals Taking ACE Inhibitor Antihypertensives

William T. Regenold; Jacob B. Blumenthal; David Loreck; Kristen Mordecai; Gina Scarinzi; Seshagiri R. Doddi; Lawrence Adler

Background/Rationale: Accumulating evidence suggests that the use of angiotensin-converting enzyme inhibitor (ACE-I) medication protects against cognitive decline in the elderly patients. We investigated whether ACE-I use was associated with higher plasma levels of amyloid-β (Aβ), possibly indicating improved Aβ clearance from brain to blood. Methods: We measured and compared plasma concentrations of Aβ42, Aβ40, and creatinine in cognitively impaired individuals with amnestic mild cognitive impairment, probable Alzheimer’s disease (AD) dementia, and mixed probable AD/vascular dementia. Results: Plasma Aβ42 levels and Aβ42/Aβ40 ratios of participants taking ACE-Is (n = 11) significantly exceeded (t = 3.1, df = 19, P = .006; U = 24, P = .029, respectively) those not taking ACE-Is (n = 10). Conclusions: This study is the first to show an association between ACE-I use and increased plasma Aβ42 level and Aβ42/Aβ40 ratio in cognitively impaired individuals. Future investigations should assess whether a possible ACE-I-induced increase in plasma Aβ42 indicates improved Aβ42 clearance from brain that contributes to protection from cognitive decline.

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Bruce Kaup

University of Maryland

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David M. Blass

Johns Hopkins University School of Medicine

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