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1.
Ann Oncol ; 33(11): 1186-1199, 2022 11.
Article in English | MEDLINE | ID: mdl-35988656

ABSTRACT

BACKGROUND: Germline variant evaluation in precision oncology opens new paths toward the identification of patients with genetic tumor risk syndromes and the exploration of therapeutic relevance. Here, we present the results of germline variant analysis and their clinical implications in a precision oncology study for patients with predominantly rare cancers. PATIENTS AND METHODS: Matched tumor and control genome/exome and RNA sequencing was carried out for 1485 patients with rare cancers (79%) and/or young adults (77% younger than 51 years) in the National Center for Tumor Diseases/German Cancer Consortium (NCT/DKTK) Molecularly Aided Stratification for Tumor Eradication Research (MASTER) trial, a German multicenter, prospective, observational precision oncology study. Clinical and therapeutic relevance of prospective pathogenic germline variant (PGV) evaluation was analyzed and compared to other precision oncology studies. RESULTS: Ten percent of patients (n = 157) harbored PGVs in 35 genes associated with autosomal dominant cancer predisposition, whereof up to 75% were unknown before study participation. Another 5% of patients (n = 75) were heterozygous carriers for recessive genetic tumor risk syndromes. Particularly, high PGV yields were found in patients with gastrointestinal stromal tumors (GISTs) (28%, n = 11/40), and more specifically in wild-type GISTs (50%, n = 10/20), leiomyosarcomas (21%, n = 19/89), and hepatopancreaticobiliary cancers (16%, n = 16/97). Forty-five percent of PGVs (n = 100/221) supported treatment recommendations, and its implementation led to a clinical benefit in 40% of patients (n = 10/25). A comparison of different precision oncology studies revealed variable PGV yields and considerable differences in germline variant analysis workflows. We therefore propose a detailed workflow for germline variant evaluation. CONCLUSIONS: Genetic germline testing in patients with rare cancers can identify the very first patient in a hereditary cancer family and can lead to clinical benefit in a broad range of entities. Its routine implementation in precision oncology accompanied by the harmonization of germline variant evaluation workflows will increase clinical benefit and boost research.


Subject(s)
Neoplasms , Young Adult , Humans , Neoplasms/diagnosis , Neoplasms/genetics , Neoplasms/therapy , Germ-Line Mutation , Genetic Predisposition to Disease , Prospective Studies , Syndrome , Precision Medicine/methods
2.
Curr Opin Clin Nutr Metab Care ; 24(6): 528-535, 2021 11 01.
Article in English | MEDLINE | ID: mdl-34456246

ABSTRACT

PURPOSE OF REVIEW: Vitamin D and folate promote vascular endothelial health and may therefore help mitigate the development of cardiovascular disease (CVD). Ultraviolet radiation (UVR) exposure stimulates cutaneous vitamin D synthesis but degrades the bioactive metabolite of folate, 5-methyltetrahydrofolate (5-MTHF). Skin melanin absorbs UVR, thereby modulating the impact of UVR exposure on vitamin D and 5-MTHF metabolism. This review presents recent findings regarding the inter-relations among UVR, skin pigmentation, folate and vitamin D, and endothelial function. RECENT FINDINGS: Evidence for roles of folic acid or vitamin D supplementation on CVD endpoints is inconsistent, although preclinical and clinical studies have demonstrated the efficacy of both micronutrients for improving endothelial function. Vitamin D deficiency is most prevalent in darkly pigmented individuals living in relatively low-UVR environments. Conversely, there is a negative relation between accumulated UVR exposure and serum folate concentration in lightly pigmented adults. The interactions among UVR and bioavailable folate and vitamin D differentially impact endothelial function in differently pigmented skin. SUMMARY: UVR exposure disparately impacts folate and vitamin D metabolism in differently pigmented skin depending upon regional UVR intensity and seasonality. These findings present new clinical research questions regarding the interactions among UVR, skin pigmentation, folate and vitamin D bioavailability, and endothelial health.


Subject(s)
Vitamin D Deficiency , Vitamin D , Adult , Folic Acid , Humans , Skin Pigmentation , Ultraviolet Rays/adverse effects
3.
Am J Physiol Heart Circ Physiol ; 319(4): H906-H914, 2020 10 01.
Article in English | MEDLINE | ID: mdl-32857616

ABSTRACT

Reduced nitric oxide (NO)-mediated cutaneous vasodilation, secondary to increased oxidative stress, presents in young African American (AA) compared with European American (EA) adults and may be modulated by vitamin D status. We assessed cutaneous microvascular function in 18 young, healthy (21 ± 2 yr; 9 men, 9 women) subjects before (pre, 8 AA, 10 EA) 4 wk of 2,000 IU/day oral vitamin D supplementation and in 13 subjects after (post, 7 AA, 6 EA) 4 wk of 2,000 IU/day oral vitamin D supplementation. Serum vitamin D concentrations [25(OH)D] were measured at each visit. Three intradermal microdialysis fibers placed in the ventral forearm were randomized for treatment with 10 µM Tempol, 100 µM apocynin, or lactated Ringer's solution (control). Local heating (39°C) induced cutaneous vasodilation; red cell flux was measured at each site (laser-Doppler flowmetry), and cutaneous vascular conductance (CVC = flux/MAP) was expressed as a percentage of maximum (28 mM sodium nitroprusside, +43°C) for each phase of local heating. After stable elevated blood flow was attained, 15 mM NG-nitro-l-arginine methyl ester (l-NAME; NO synthase inhibitor) was perfused at all sites to quantify the NO contribution to cutaneous vasodilation (%NO), calculated as the difference between local heating and l-NAME plateaus. Serum [25(OH)D], the magnitude of the local heating response, and %NO were all lower in AAs versus EAs (P < 0.01). Tempol (P = 0.01), but not apocynin (P ≥ 0.19), improved the local heating response and %NO. Four weeks of supplementation improved serum [25(OH)D], the local heating response, and %NO in AAs (P ≤ 0.04) but not in EAs (P ≥ 0.41). Vitamin D supplementation mitigated endothelial dysfunction, an antecedent to overt cardiovascular disease (CVD), in otherwise healthy, young AA adults.NEW & NOTEWORTHY Endothelial dysfunction, an antecedent to overt cardiovascular disease (CVD), is observed earlier and more frequently in otherwise healthy African Americans (AAs) when compared with other ethnic groups. Vitamin D may modulate endothelial function, and darkened skin pigmentation increases risk of vitamin D deficiency. We show that 4 wk of 2,000 IU/day vitamin D supplementation improves microvascular responses to local heating in AAs. Ensuring adequate vitamin D status may mitigate development of cardiovascular dysfunction in this at-risk population.


Subject(s)
Black or African American , Dietary Supplements , Microvessels/drug effects , Nitric Oxide/metabolism , Skin/blood supply , Vasodilation/drug effects , Vitamin D Deficiency/drug therapy , Vitamin D/administration & dosage , Age Factors , Dietary Supplements/adverse effects , Female , Humans , Male , Microvessels/metabolism , Microvessels/physiopathology , Time Factors , Treatment Outcome , Vitamin D/adverse effects , Vitamin D/analogs & derivatives , Vitamin D/blood , Vitamin D Deficiency/blood , Vitamin D Deficiency/ethnology , Vitamin D Deficiency/physiopathology , Young Adult
4.
J Appl Physiol (1985) ; 126(4): 1042-1048, 2019 04 01.
Article in English | MEDLINE | ID: mdl-30763158

ABSTRACT

Aging is associated with altered water, electrolyte, and glucose handling. Alternative beverages to those containing carbohydrate (CHO) should be considered for older adults. We hypothesized that reduced sodium (CNa+) and/or water (CH2O) clearance would underlie greater beverage retention in older compared with young adults, secondary to reduced glomerular filtration rate (GFR). We further hypothesized that amino acid (AA)- and CHO-based beverages would promote retention better than water. Over five visits, 12 young (23 ± 3 yr; 7 men, 5 women) and 12 older (67 ± 6 yr; 5 men, 7 women) subjects consumed 1 liter of distilled water or beverages with 6% CHO, 0.46 g/l Na+ [Gatorade (GAT)]; 2.5% CHO, 0.74 g/l Na+ [Pedialyte (PED)]; 5 AA, 1.04 g/l Na+ [enterade (ENT)-5]; or 8 AA, 1.38 g/l Na+ (ENT-8) over 30 min. Blood and urine were collected every hour for 4 h after ingestion; retention, CH2O, and CNa+ were calculated at 2 and 4 h. Additional calculations adjusted CH2O and CNa+ for estimated GFR (eGFR). Water yielded the lowest retention in both groups ( P ≤ 0.02). Retention was higher in older vs. young adults except for ENT-8 at 4 h ( P = 0.73). CH2O was higher for older vs. young adults for GAT at 2 h ( P < 0.01) and GAT and PED at 4 h ( P < 0.01) after ingestion but was otherwise similar between groups. CNa+ was lower in older vs. young adults except for ENT-8 ( P ≥ 0.19). Adjusting for eGFR resulted in higher CH2O for all beverages in older vs. young adults ( P < 0.05) but did not influence CNa+. Older adults may better retain beverages with less Na+ than young adults because of reduced CNa+. AA- and CHO-based electrolyte-rich beverages may similarly promote beverage retention. NEW & NOTEWORTHY Commercially available amino acid (AA)-containing beverages may provide an alternative to traditional carbohydrate (CHO)-containing beverages, particularly for older adults with attenuated water, electrolyte, and glucose handling. We compared beverage retention and free water and sodium clearance between young and older adults after ingestion of water, two CHO-based beverages, and two AA-based beverages. Our data suggest that older adults better retain beverages with less sodium compared with young adults and that AA-based and CHO-based electrolyte-containing beverages similarly promote retention.


Subject(s)
Eating/physiology , Electrolytes/metabolism , Sodium/metabolism , Water-Electrolyte Balance/physiology , Water/metabolism , Adult , Aged , Beverages , Blood Glucose/metabolism , Dehydration/physiopathology , Dietary Carbohydrates/metabolism , Dietary Supplements , Exercise/physiology , Female , Glomerular Filtration Rate/physiology , Glucose/metabolism , Humans , Ions/metabolism , Male , Young Adult
5.
Bioprocess Biosyst Eng ; 40(4): 479-497, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28040871

ABSTRACT

Computational methods have enabled the discovery of non-intuitive strategies to enhance the production of a variety of target molecules. In the case of succinate production, reviews covering the topic have not yet analyzed the impact and future potential that such methods may have. In this work, we review the application of computational methods to the production of succinic acid. We found that while a total of 26 theoretical studies were published between 2002 and 2016, only 10 studies reported the successful experimental implementation of any kind of theoretical knowledge. None of the experimental studies reported an exact application of the computational predictions. However, the combination of computational analysis with complementary strategies, such as directed evolution and comparative genome analysis, serves as a proof of concept and demonstrates that successful metabolic engineering can be guided by rational computational methods.


Subject(s)
Computational Biology , Metabolic Engineering/methods , Models, Biological , Succinic Acid/metabolism
6.
Article in German | MEDLINE | ID: mdl-25776522

ABSTRACT

The traditional separation of health care into sectors in Germany causes communication problems that hinder continuous, patient-oriented care. This is most evident in the transition from inpatient to outpatient care. That said, there are also breaks in the flow of information, a lack of supply, or even incorrect information flowing within same-sector care. The transition from a division of functions into sectors to a patient-oriented process represents a change in the paradigm of health care that can only be successfully completed with considerable effort. Germany's statutory health insurance (SHI) funds play a key role here, as they are the contracting parties as well as the financiers of integrated care, and are strategically located at the center of the development process.The objective of this article is to explore how Germany's SHI funds view integrated care, what they regard as being the drivers of and barriers to transitioning to such a system, and what recommendations they can provide with regard to the further development of integrated care. For this purpose semi-structured interviews with board members and those responsible for implementing integrated care into the operations of ten SHI funds representing more than half of Germany's SHI-insured population were conducted. According to the interviewees, a better framework for integrated care urgently needs to be developed and rendered more receptive to innovation.Only in this way will the widespread stagnation of the past several years be overcome. The deregulation of § 140a-d SGB V and the establishment of a uniform basis for new forms of care in terms of a new innovation clause are among the central recommendations of this article. The German federal government's innovation fund was met with great hope, but also implied risks. Nonetheless, the new law designed to strengthen health care overall generated high expectations.


Subject(s)
Delivery of Health Care, Integrated/organization & administration , Health Maintenance Organizations/organization & administration , Health Services Accessibility/organization & administration , Models, Organizational , National Health Programs/organization & administration , Forecasting , Germany , Health Services Research/trends , Organizational Objectives
7.
Nervenarzt ; 83(12): 1542-50, 2012 Dec.
Article in German | MEDLINE | ID: mdl-23180054

ABSTRACT

Delayed cerebral ischemia (DCI) is the second most important impacting factor for functional outcome after aneurysmal subarachnoid hemorrhage (SAH) following the initial severity of the bleeding. In contrast to the initial SAH severity the presence and consequences of DCI can be managed with prophylactic and therapeutic interventions. The previous notion of treatment of angiographically observed vasospasm has not been shown to be successful.This article covers prevention, monitoring and therapeutic concepts for patients with SAH with emphasis on the efficacy for DCI and current and ongoing research projects.


Subject(s)
Angioplasty, Balloon/methods , Brain Ischemia/diagnosis , Brain Ischemia/etiology , Brain Ischemia/therapy , Nimodipine/therapeutic use , Subarachnoid Hemorrhage/diagnosis , Subarachnoid Hemorrhage/therapy , Combined Modality Therapy , Critical Care/methods , Humans , Subarachnoid Hemorrhage/complications , Vasodilator Agents/therapeutic use
8.
Urologe A ; 50(12): 1566-72, 2011 Dec.
Article in German | MEDLINE | ID: mdl-22108909

ABSTRACT

The German health care system is faced with enormous challenges: population ageing, more chronic diseases and multimorbidity. The fragmentation of medical care into disconnected parts-ambulant and clinical services, pharmaceutical provision, nursing care etc.-is inefficient and inhibits coordinated courses of treatment. Instead of this new types of organizational structures and processes are needed. By means of different health care acts the German government has supported innovative medical care structures for many years. In the meantime, 30,000 doctors have joined 400 physician networks. Their aims are to improve the coordination of services, to facilitate collaboration among providers and to ensure better health care to the population. Furthermore, those interdisciplinary networks are crucial prerequisites for integrated health care. But there is still a lot of work to do. The successful integration of the components of health care into functioning process chains depends on political, economic and sociocultural parameters.


Subject(s)
Community Networks/organization & administration , Delivery of Health Care, Integrated/organization & administration , Delivery of Health Care/trends , Models, Organizational , Physicians/organization & administration , Germany
9.
Neurocrit Care ; 12(3): 346-51, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20033353

ABSTRACT

BACKGROUND: For endovascular treatment of vasospasm after aneurysmal subarachnoid hemorrhage (aSAH), an intraarterial treatment course with the calcium channel antagonist nimodipine infused for 30 min is proposed. As some patients still show ongoing vasospasm thereafter, we report on our experience with an extended time period of selective intraarterial nimodipine administration. METHODS: In nine patients with aSAH and refractory cerebral vasospasm, we left the catheter in place within the internal carotid artery after angiography. On the neurosurgical ICU, a continuous infusion of intraarterial nimodipine was commenced, combined with intraarterial heparin anticoagulation. Therapy was controlled with extended neuromonitoring techniques. RESULTS: Three patients died from refractory vasospasm and a fourth suffered lethal sepsis. Three patients survived in a good clinical condition, two of them without apparent neurologic deficit. The efficacy of intraarterial nimodipine was best verified with regional CBF monitoring. TCD failed to detect vasospasm in two patients and missed improvement in four. Brain tissue oxygenation increased in all patients, but was not indicative of vasospasm in one. CT perfusion reflected the treatment course adequately in the qualitative scans. CONCLUSION: Selective continuous intraarterial nimodipine treatment for refractory cerebral vasospasm after aSAH seems feasible and may add to the endovascular therapeutic options. Appropriate monitoring technology is essential for further investigation of this novel technique.


Subject(s)
Calcium Channel Blockers/administration & dosage , Infusions, Intra-Arterial , Nimodipine/administration & dosage , Postoperative Complications/drug therapy , Subarachnoid Hemorrhage/surgery , Vasodilator Agents/administration & dosage , Vasospasm, Intracranial/drug therapy , Adult , Anticoagulants/administration & dosage , Anticoagulants/adverse effects , Calcium Channel Blockers/adverse effects , Cerebral Angiography , Drug Therapy, Combination , Embolization, Therapeutic , Female , Heparin/administration & dosage , Heparin/adverse effects , Hospital Mortality , Humans , Image Processing, Computer-Assisted , Male , Middle Aged , Nimodipine/adverse effects , Postoperative Complications/mortality , Subarachnoid Hemorrhage/mortality , Surgical Instruments , Tomography, X-Ray Computed , Ultrasonography, Doppler, Transcranial , Vasodilator Agents/adverse effects , Vasospasm, Intracranial/mortality
10.
J Anim Ecol ; 78(1): 247-52, 2009 Jan.
Article in English | MEDLINE | ID: mdl-19120605

ABSTRACT

1. Bumblebees are important pollinators in natural as well as agricultural ecosystems. Estimates of foraging range, population size and genetic population structure so far have been based on worker samples alone. Here we include both males and workers in a population genetic analysis to infer the contribution of males to these important ecological parameters. 2. The population genetic (microsatellite) analyses of Bombus terrestris L. populations on the island of Cabrera (Spain) and Halle (Germany) revealed high heterozygosities (0.60 +/- 0.08 to 0.77 +/- 0.13) and neither a deviation from Hardy-Weinberg equilibrium nor linkage disequilibrium. 3. We detected five colonies (census population size) for the island population and 27 to 68 for the German mainland population. The genetic effective population sizes were N(e) = 7.5 for the island and 40.5 to 102 for the mainland population respectively. 4. There was a significant genetic subdifferentiation between the male and the worker population samples, suggesting that males originated from different and/or more distant colonies than workers. 5. Based on the colony numbers, we estimated the flight range of males, which ranged from 2.6 km to 9.9 km, much further than worker flight ranges. Bumblebee-mediated pollen flow will therefore be much further than expected based on the foraging range of workers alone if males also contribute to pollination.


Subject(s)
Bees/physiology , Flight, Animal/physiology , Animals , Bees/genetics , Genetics, Population , Geography , Male , Microsatellite Repeats , Pollen/physiology , Population Density
11.
Br J Ophthalmol ; 90(9): 1188-96, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16929063

ABSTRACT

BACKGROUND: Until recently, only two options were available for the treatment of choroidal neovascularisation (CNV) associated with age related macular degeneration (AMD)-thermal laser photocoagulation and photodynamic therapy with verteporfin (PDT-V). However, new treatments for CNV are in development, and data from phase III clinical trials of some of these pharmacological interventions are now available. In light of these new data, expert guidance is required to enable retina specialists with expertise in the management of AMD to select and use the most appropriate therapies for the treatment of neovascular AMD. METHODS: Consensus from a round table of European retina specialists was obtained based on best available scientific data. Data rated at evidence levels 1 and 2 were evaluated for laser photocoagulation, PDT-V, pegaptanib sodium, and ranibizumab. Other treatments discussed are anecortave acetate, triamcinolone acetonide, bevacizumab, rostaporfin (SnET2), squalamine, and transpupillary thermotherapy. RESULTS: PDT-V is currently recommended for subfoveal lesions with predominantly classic CNV, or with occult with no classic CNV with evidence of recent disease progression and a lesion size

Subject(s)
Choroidal Neovascularization/drug therapy , Macular Degeneration/drug therapy , Antibodies, Monoclonal/therapeutic use , Antibodies, Monoclonal, Humanized , Aptamers, Nucleotide/therapeutic use , Choroidal Neovascularization/etiology , Choroidal Neovascularization/therapy , Evidence-Based Medicine , Humans , Macular Degeneration/complications , Macular Degeneration/therapy , Photochemotherapy/methods , Pregnadienediols/therapeutic use , Ranibizumab , Treatment Outcome , Triamcinolone Acetonide/therapeutic use
12.
Immunol Invest ; 34(3): 361-80, 2005.
Article in English | MEDLINE | ID: mdl-16136786

ABSTRACT

The cytokine interleukin 12 (IL-12) has resulted in notable anti-tumor activity in animal models and in patients and as a result there is considerable interest in learning how to maximize its therapeutic potential while at the same time reducing its known toxic side effects. Strategies which could maintain its effectiveness while permitting reduced dosage could be especially valuable. In this study we used BALB/c mice bearing CT26 tumors as a model for testing whether combining murine IL-12 with a mild (fever range) whole body hyperthermia protocol could result in such a strategy. Our data revealed that 100 ng of IL-12/mouse/day used in combination with FR-WBH was as effective as one in which 300 ng of IL-12/mouse/day was used alone. Importantly, the mice receiving the combination treatment exhibited fewer treatment related toxicities compared to those that received high dose IL-12 alone. Initiation of the IL-12 treatment immediately after FR-WBH induced the greatest anti-tumor effect. This effect does not appear to depend on differences in IL-12-induced IFN-gamma, but may involve production of nitric oxide (NO), since treatment of mice with a NOS inhibitor, NG-monomethyl-L-arginine (L-NMA), abolishes the additive anti-tumor effect of the combination treatment. Collectively, these data suggest that modification of physiological parameters in the host by mild fever-like thermal stimuli may be an effective and feasible adjuvant for cytokine-based immunotherapeutic strategies.


Subject(s)
Adjuvants, Immunologic/pharmacology , Antineoplastic Agents/pharmacology , Hyperthermia, Induced , Interleukin-12/pharmacology , Animals , Cell Line, Tumor , Female , Interferon-gamma/biosynthesis , Macrophages/drug effects , Mice , Mice, Inbred BALB C , Nitric Oxide/biosynthesis , Time Factors
13.
Rev. bras. farmacogn ; 15(1): 71-76, jan.-mar. 2005. ilus
Article in English | LILACS | ID: lil-570887

ABSTRACT

The Acacia genus has presented various secondary metabolites, such as tannins, flavonoids, alkaloids and gums. Preparations from different species have been applied for diabetes, gastrointestinal disorders and inflammatory diseases in the traditional medicine and have demonstrated cytotoxic, antimicrobial and antiparasitic activities. Acacia podalyriifolia A. Cunn. ex G. Don (Fabaceae) is a small wood, indigenous to Australia and cultivated worldwide for its ornamental feature. This work aimed to characterize the anatomy of the phyllode and stem, in order to contribute to the species identification. The botanical material was fixed, sectioned and prepared according to usual light and scanning microtechniques. The epidermal cells, in surface view, are polygonal and coated with striate and thick cuticle, and filaments of epicuticular wax. Paracytic stomata and unicellular non-glandular trichomes are seen. Palisade and ground parenchymas, and minor collateral bundles with xylem directed alternately to upper and lower sides occur in the blade. The midrib shows two collateral bundles facing each other. The stem, in incipient secondary growth, exhibits epidermis, annular collenchyma, sclerenchymatic sheath and collateral vascular organization. Cells containing phenolic compounds and prisms of calcium oxalate are observed.

14.
Anaesthesist ; 51(10): 843-52, 2002 Oct.
Article in German | MEDLINE | ID: mdl-12395176

ABSTRACT

Since imbalances in the immune system of the critically ill patient have been demonstrated, the role of the gastrointestinal tract for the pathogenesis of multiple organ failure has been a focus of research in intensive care medicine. Particularly, the integrity of the intestinal barrier function has been studied experimentally and clinically. The enormous number of gram-negative bacteria up to 10(11)/ml intestinal liquid inducing the release of significant amounts of endotoxin, is considered to be a vital threat to the intensive care unit (ICU) patient. Acute failure of the intestinal barrier following various types of severe shock or following parenteral nutrition inducing atrophy of intestinal mucosa may lead to multiple organ dysfunction. Maintenance of hemodynamic stability is a mainstay of therapy of the critically ill. In addition, the intestinal integrity can be preserved by the early onset of enteral nutrition. Moreover, recent concepts of enteral nutrition using immunomodulating nutrients like omega-3-fatty acids, glutamine, arginine, and nucleotides are under clinical evaluation.


Subject(s)
Critical Illness/therapy , Enteral Nutrition , Humans , Immune System/immunology , Immune System/physiology , Intestinal Mucosa/immunology , Intestinal Mucosa/physiopathology
15.
Control Clin Trials ; 22(6): 689-704, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11738125

ABSTRACT

This paper describes the study design, methodological considerations, and baseline characteristics of a clinical trial to determine if intense (48 weeks, twice per week) Tai Chi practice can reduce the frequency of falls among older adults transitioning to frailty compared to a wellness education program. Twenty facilities will be stratified on socioeconomic status and facility type and randomly assigned to one of the two interventions. Secondary outcome measurements include variables related to function, behavior, and the biomechanics of movement. This study is unique because it represents an effort to offer a novel physical intervention to a large sample of transitional frail adults, a population that has received few formal exercise interventions. In addition to bringing the interventions into facilities, a 1-year follow-up is also included to assess rates of change in outcome measurements.


Subject(s)
Accidental Falls/prevention & control , Frail Elderly , Personnel Selection/methods , Randomized Controlled Trials as Topic/methods , Tai Ji , Aged , Aged, 80 and over , Biomechanical Phenomena , Educational Status , Female , Georgia , Humans , Male , Multicenter Studies as Topic , Research Design
16.
Appl Psychophysiol Biofeedback ; 26(2): 155-74, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11480166

ABSTRACT

This keynote presentation highlights events that have contributed to scientific explorations of one research clinician. Steve Wolf traces his scientific roots to early studies in single motor unit control under the guidance of his primary mentor, John Basmajian, MD. This work led to subsequent studies on the role of EMG feedback in predicting successful outcomes in upper extremity use and in ambulatory capabilities among patients with chronic stroke. These findings are contrasted to further efforts to condition entire reflexes rather than individual muscles through use of operant-conditioning paradigms. The findings from applications of EMG biofeedback to stroke patients became the basis for minimal motor criteria in the treatment of the impaired upper extremities of patients with chronic stroke, using "forced use" or "constraint-induced movement therapy." Last, investigations into center of pressure feedback using computerized balance machines resulted in a series of experiments that ultimately led to the finding that Tai Chi as an exercise form for older adults can have a substantially favorable effect in delaying the onset of fall events.


Subject(s)
Biofeedback, Psychology , Muscle, Skeletal/physiology , Tai Ji , Electromyography , Humans
17.
Am J Physiol Endocrinol Metab ; 281(2): E197-206, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11440894

ABSTRACT

The present study was designed to determine whether consumption of an oral essential amino acid-carbohydrate supplement (EAC) before exercise results in a greater anabolic response than supplementation after resistance exercise. Six healthy human subjects participated in two trials in random order, PRE (EAC consumed immediately before exercise), and POST (EAC consumed immediately after exercise). A primed, continuous infusion of L-[ring-(2)H(5)]phenylalanine, femoral arteriovenous catheterization, and muscle biopsies from the vastus lateralis were used to determine phenylalanine concentrations, enrichments, and net uptake across the leg. Blood and muscle phenylalanine concentrations were increased by approximately 130% after drink consumption in both trials. Amino acid delivery to the leg was increased during exercise and remained elevated for the 2 h after exercise in both trials. Delivery of amino acids (amino acid concentration times blood flow) was significantly greater in PRE than in POST during the exercise bout and in the 1st h after exercise (P < 0.05). Total net phenylalanine uptake across the leg was greater (P = 0.0002) during PRE (209 +/- 42 mg) than during POST (81 +/- 19). Phenylalanine disappearance rate, an indicator of muscle protein synthesis from blood amino acids, increased after EAC consumption in both trials. These results indicate that the response of net muscle protein synthesis to consumption of an EAC solution immediately before resistance exercise is greater than that when the solution is consumed after exercise, primarily because of an increase in muscle protein synthesis as a result of increased delivery of amino acids to the leg.


Subject(s)
Amino Acids, Essential/administration & dosage , Carbohydrates/administration & dosage , Muscle, Skeletal/drug effects , Muscle, Skeletal/metabolism , Physical Exertion/physiology , Administration, Oral , Adult , Biopsy , Blood Flow Velocity/drug effects , Deuterium , Dietary Supplements , Female , Humans , Infusions, Intravenous , Insulin/blood , Leg , Male , Phenylalanine/administration & dosage , Phenylalanine/blood , Phenylalanine/pharmacokinetics , Protein Biosynthesis , Regional Blood Flow/drug effects , Time Factors
18.
Crit Care Med ; 28(2): 504-10, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10708191

ABSTRACT

OBJECTIVE: Hepatocyte growth factor (HGF) has been shown to modulate the acute-phase response in vitro. The specific in vivo role of HGF in this multifactorial response, however, remains unknown. This study examines the effects of exogenous HGF on the acute-phase response in thermally injured rats. DESIGN: Prospective, randomized, laboratory study. SETTINGS: Shriners Hospital for Children and University of Texas Medical Branch laboratories. SUBJECTS: Fifty-six male Sprague-Dawley rats (weight range, 300-325 g). INTERVENTION: Animals received a 60% total body surface area third-degree scald burn and were randomly divided to receive either 400 microg/kg/day i.v. HGF or saline (control). MEASUREMENTS AND MAIN RESULTS: Serum acute-phase proteins, cytokines, and insulin-like growth factor (IGF)-I concentrations, as well as liver weight, protein and triglyceride content, IGF-I concentrations, and cytokine gene expression were measured 1, 2, 5, or 7 days after burn. Serum albumin was increased on days 2, 5, and 7 after burn, and transferrin was increased on day 7 after burn in HGF-treated rats compared with controls (p<.05). HGF increased alpha2-macroglobulin concentrations on postburn days 2, 5, and 7 compared with controls (p<.05). Serum interleukin-6 and tumor necrosis factor-alpha were significantly higher within 2 days of burn in rats treated with HGF (p<.05). HGF increased the hepatic gene expression of tumor necrosis factor-alpha compared with controls (p<.05). Serum IGF-I decreased in rats receiving HGF 1, 2, and 5 days after burn, whereas liver IGF-I concentrations were higher on days 1 and 7 after burn compared with controls (p<.05). Hepatic protein concentrations were higher in the HGF group compared with controls on postburn days 1, 2, and 7, with a concomitant increase in total liver weight (p<.05). HGF exerted a strong mitogenic effect on hepatocytes 1 and 2 days after thermal injury compared with controls (p<.05). CONCLUSIONS: These findings suggest that HGF modulates the acute-phase response in vivo after burn and causes changes in liver morphology.


Subject(s)
Acute-Phase Reaction/drug therapy , Acute-Phase Reaction/etiology , Burns/complications , Burns/immunology , Hepatocyte Growth Factor/therapeutic use , Acute-Phase Proteins/drug effects , Acute-Phase Proteins/metabolism , Acute-Phase Reaction/blood , Acute-Phase Reaction/immunology , Acute-Phase Reaction/pathology , Animals , Body Surface Area , Cytokines/blood , Cytokines/drug effects , Disease Models, Animal , Drug Evaluation, Preclinical , Hepatocyte Growth Factor/immunology , Hepatocyte Growth Factor/pharmacology , Insulin-Like Growth Factor I/drug effects , Insulin-Like Growth Factor I/metabolism , Liver/drug effects , Liver/immunology , Liver/pathology , Male , Random Allocation , Rats , Rats, Sprague-Dawley , Serum Albumin/drug effects , Serum Albumin/metabolism , Time Factors , Transferrin/drug effects , Transferrin/metabolism , alpha-Macroglobulins/drug effects , alpha-Macroglobulins/metabolism
19.
J Appl Physiol (1985) ; 88(2): 386-92, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10658002

ABSTRACT

This study was designed to determine the response of muscle protein to the bolus ingestion of a drink containing essential amino acids and carbohydrate after resistance exercise. Six subjects (3 men, 3 women) randomly consumed a treatment drink (6 g essential amino acids, 35 g sucrose) or a flavored placebo drink 1 h or 3 h after a bout of resistance exercise on two separate occasions. We used a three-compartment model for determination of leg muscle protein kinetics. The model involves the infusion of ring-(2)H(5)-phenylalanine, femoral arterial and venous blood sampling, and muscle biopsies. Phenylalanine net balance and muscle protein synthesis were significantly increased above the predrink and corresponding placebo value (P < 0.05) when the drink was taken 1 or 3 h after exercise but not when the placebo was ingested at 1 or 3 h. The response to the amino acid-carbohydrate drink produced similar anabolic responses at 1 and 3 h. Muscle protein breakdown did not change in response to the drink. We conclude that essential amino acids with carbohydrates stimulate muscle protein anabolism by increasing muscle protein synthesis when ingested 1 or 3 h after resistance exercise.


Subject(s)
Amino Acids, Essential/pharmacology , Carbohydrates/pharmacology , Exercise/physiology , Muscle Proteins/drug effects , Administration, Oral , Amino Acids, Essential/administration & dosage , Analysis of Variance , Carbohydrates/administration & dosage , Dietary Supplements , Female , Femoral Artery/drug effects , Femoral Artery/metabolism , Femoral Vein/drug effects , Femoral Vein/metabolism , Humans , Insulin/blood , Leg/blood supply , Male , Muscle Proteins/metabolism , Phenylalanine/drug effects , Phenylalanine/metabolism , Regional Blood Flow/drug effects , Time Factors
20.
Shock ; 12(3): 181-7, 1999 Sep.
Article in English | MEDLINE | ID: mdl-10485595

ABSTRACT

Recombinant human growth hormone (rhGH) and hepatocyte growth factor (HGF) have both been shown to individually modulate hepatic acute phase reactant proteins and cytokine expression following trauma through different pathways. Recombinant hGH has also been shown to decrease serum and hepatic HGF concentrations after a thermal injury. We hypothesized that the combination of rhGH plus HGF improves the burn-induced acute phase response. Fifty-six male Sprague-Dawley rats received a 60% TBSA third-degree scald burn and were randomly divided to receive either rhGH (2.5 mg/kg/day sc.) plus HGF (200 microg/kg i.v. every 12 h) or placebo (saline). Rats were sacrificed on post-burn days 1, 2, 5, or 7 and serum constitutive and acute phase proteins, TNF-alpha, IL-1beta, IL-6 and liver total protein measured. Hepatic cytokine gene expression, triglyceride concentration, and hepatocyte proliferation were also measured. In rats receiving rhGH/HGF, serum albumin increased on days 5 and 7 and transferrin on day 7 after burn compared to placebo (P<0.05). Haptoglobin decreased 5 days after burn compared to placebo (P<0.05). RhGH/HGF increased serum TNF-alpha on day 2 after burn, while it decreased serum IL-1beta on day 1 after burn compared with placebo (P<0.05). RhGH/HGF had no effect on hepatic cytokine gene expression compared with placebo. Liver total protein content and hepatocyte proliferation increased on days 1, 2, 5, and 7 after burn with rhGH/HGF treatment (P<0.05). These findings indicate that rhGH in combination with HGF exert additive effects on constitutive hepatic proteins and partial inhibitory effects on acute phase protein and cytokine expression. RhGH/HGF has a strong mitogenic effect on hepatocytes.


Subject(s)
Acute-Phase Reaction/drug therapy , Hepatocyte Growth Factor/pharmacology , Human Growth Hormone/pharmacology , Acute-Phase Reaction/etiology , Acute-Phase Reaction/metabolism , Animals , Burns/complications , Burns/drug therapy , Burns/metabolism , Drug Evaluation, Preclinical , Drug Therapy, Combination , Human Growth Hormone/pharmacokinetics , Humans , Liver/drug effects , Liver/pathology , Male , Rats , Rats, Sprague-Dawley
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