LIVIVO - The Search Portal for Life Sciences

zur deutschen Oberfläche wechseln
Advanced search

Search results

Result 1 - 7 of total 7

Search options

  1. Article ; Online: Peer providers and linkage with buprenorphine care after hospitalization: A retrospective cohort study.

    Jack, Helen E / Denisiuk, Eric D / Collins, Brett A / Stephens, Dan / Blalock, Kendra L / Klein, Jared W / Bhatraju, Elenore P / Merrill, Joseph O / Hallgren, Kevin A / Tsui, Judith I

    Substance abuse

    2022  Volume 43, Issue 1, Page(s) 1308–1316

    Abstract: ... ...

    Abstract Background
    MeSH term(s) Adult ; Buprenorphine/therapeutic use ; Hospitalization ; Humans ; Opiate Substitution Treatment ; Opioid-Related Disorders/drug therapy ; Retrospective Studies
    Chemical Substances Buprenorphine (40D3SCR4GZ)
    Language English
    Publishing date 2022-07-25
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 1458030-5
    ISSN 1547-0164 ; 0889-7077
    ISSN (online) 1547-0164
    ISSN 0889-7077
    DOI 10.1080/08897077.2022.2095078
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  2. Article ; Online: One-Year Follow-Up of Vascular Intervention Trials Disrupted by the COVID-19 Pandemic: A Use-Case landscape.

    Rymer, Jennifer A / Kirtane, Ajay J / Farb, Andrew / Malone, Misti / Jaff, Michael R / Seward, Kirk / Stephens, Dan / Barakat, Mark K / Krucoff, Mitchell W

    Cardiovascular revascularization medicine : including molecular interventions

    2022  Volume 45, Page(s) 67–73

    Abstract: Introduction: The COVID-19 pandemic had an unprecedented impact on cardiovascular clinical research. The decision-making and state of study operations in cardiovascular trials 1-year after interruption has not been previously described.: Methods: In ... ...

    Abstract Introduction: The COVID-19 pandemic had an unprecedented impact on cardiovascular clinical research. The decision-making and state of study operations in cardiovascular trials 1-year after interruption has not been previously described.
    Methods: In the spring of 2020, we created a pandemic impact task force to develop a landscape of use case scenarios from 17 device trials of peripheral artery disease (PAD) and coronary artery disease (CAD) interventions. In conjunction with publicly available (clinictrials.gov) study inclusion criteria, primary endpoints and study design, information was shared for this use-case landscape by trial leadership and data owners.
    Results: A total of 17 actively enrolling trials (9 CAD and 8 PAD) volunteered to populate the use case landscape. All 17 were multicenter studies (12 in North America and 5 international). Fifteen studies were industry-sponsored, of which 13 were FDA approved IDEs, one was PCORI-sponsored and two were sponsored by the NIH. Enrollment targets ranged from 150 to 9000 pts. At the time of interruption, 5 trials were <20 % enrolled, 9 trials were 50-80 % enrolled and 3 trials were >80 % enrolled. At 1 year, the majority of studies were continuing to enroll in the context of more sporadic but ongoing pandemic activity.
    Conclusions: At 1 year from the first surge interruptions, most trials had resumed enrollment. Trials most heavily interrupted were trials early in enrollment and those trials not able to pivot to virtual patient and site visits. Further work is needed to determine the overall impact on vascular intervention trials disrupted during the COVID-19 pandemic.
    MeSH term(s) Humans ; COVID-19/epidemiology ; Pandemics ; Research Design
    Language English
    Publishing date 2022-07-26
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2212113-4
    ISSN 1878-0938 ; 1553-8389
    ISSN (online) 1878-0938
    ISSN 1553-8389
    DOI 10.1016/j.carrev.2022.07.018
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  3. Article: Cutaneous vasoconstrictor response to whole body skin cooling is altered by time of day.

    Aoki, Ken / Stephens, Dan P / Saad, Adham R / Johnson, John M

    Journal of applied physiology (Bethesda, Md. : 1985)

    2003  Volume 94, Issue 3, Page(s) 930–934

    Abstract: To test for a diurnal difference in the vasoconstrictor control of the cutaneous circulation, we performed whole body skin cooling (water-perfused suits) at 0600 (AM) and 1600 (PM). After whole body skin temperature (T(sk)) was controlled at 35 degrees C ...

    Abstract To test for a diurnal difference in the vasoconstrictor control of the cutaneous circulation, we performed whole body skin cooling (water-perfused suits) at 0600 (AM) and 1600 (PM). After whole body skin temperature (T(sk)) was controlled at 35 degrees C for 10 min, it was progressively lowered to 32 degrees C over 18-20 min. Skin blood flow (SkBF) was monitored by laser-Doppler flowmetry at three control sites and at a site that had been pretreated with bretylium by iontophoresis to block noradrenergic vasoconstriction. After whole body skin cooling, maximal cutaneous vascular conductance (CVC) was measured by locally warming the sites of SkBF measurement to 42 degrees C for 30 min. Before whole body skin cooling, sublingual temperature (T(or)) in the PM was significantly higher than that in the AM (P < 0.05), but CVC, expressed as a percentage of maximal CVC (%CVC(max)), was not statistically different between AM and PM. During whole body skin cooling, %CVC(max) levels at bretylium-treated sites in AM or PM were not significantly reduced from baseline. In the PM, %CVC(max) at control sites fell significantly at T(sk) of 34.3 +/- 0.01 degrees C and lower (P < 0.05). In contrast, in the AM %CVC(max) at control sites was not significantly reduced from baseline until T(sk) reached 32.3 +/- 0.01 degrees C and lower (P < 0.05). Furthermore, the decrease in %CVC(max) in the PM was significantly greater than that in AM at T(sk) of 33.3 +/- 0.01 degrees C and lower (P < 0.05). Integrative analysis of the CVC response with respect to both T(or) and T(sk) showed that the cutaneous vasoconstrictor response was shifted to higher internal temperatures in the PM. These findings suggest that during whole body skin cooling the reflex control of the cutaneous vasoconstrictor system is shifted to a higher internal temperature in the PM. Furthermore, the slope of the relationship between CVC and T(sk) is steeper in the PM compared with that in the AM.
    MeSH term(s) Adolescent ; Adult ; Blood Pressure/drug effects ; Blood Pressure/physiology ; Bretylium Compounds/administration & dosage ; Bretylium Compounds/pharmacology ; Circadian Rhythm/physiology ; Cold Temperature ; Heart Rate/drug effects ; Heart Rate/physiology ; Humans ; Iontophoresis ; Male ; Reflex/physiology ; Skin Physiological Phenomena ; Skin Temperature/physiology ; Stress, Physiological/physiopathology ; Vasoconstriction/physiology ; Vasodilation/drug effects ; Vasodilation/physiology
    Chemical Substances Bretylium Compounds ; bretylium (RZR75EQ2KJ)
    Language English
    Publishing date 2003-03
    Publishing country United States
    Document type Clinical Trial ; Journal Article ; Randomized Controlled Trial ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, P.H.S.
    ZDB-ID 219139-8
    ISSN 1522-1601 ; 8750-7587 ; 0021-8987 ; 0161-7567
    ISSN (online) 1522-1601
    ISSN 8750-7587 ; 0021-8987 ; 0161-7567
    DOI 10.1152/japplphysiol.00792.2002
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  4. Article: Modification of cutaneous vasodilator response to heat stress by daytime exogenous melatonin administration.

    Aoki, Ken / Stephens, Dan P / Zhao, Kun / Kosiba, Wojciech A / Johnson, John M

    American journal of physiology. Regulatory, integrative and comparative physiology

    2006  Volume 291, Issue 3, Page(s) R619–24

    Abstract: In humans, the nocturnal fall in internal temperature is associated with increased endogenous melatonin and with a shift in the thermoregulatory control of skin blood flow (SkBF), suggesting a role for melatonin in the control of SkBF. The purpose of ... ...

    Abstract In humans, the nocturnal fall in internal temperature is associated with increased endogenous melatonin and with a shift in the thermoregulatory control of skin blood flow (SkBF), suggesting a role for melatonin in the control of SkBF. The purpose of this study was to test whether daytime exogenous melatonin would shift control of SkBF to lower internal temperatures during heat stress, as is seen at night. Healthy male subjects (n = 8) underwent body heating with melatonin administration (Mel) or without (control), in random order at least 1 wk apart. SkBF was monitored at sites pretreated with bretylium to block vasoconstrictor nerve function and at untreated sites. Cutaneous vascular conductance, calculated from SkBF and arterial pressure, sweating rate (SR), and heart rate (HR) were monitored. Skin temperature was elevated to 38 degrees C for 35-50 min. Baseline esophageal temperature (Tes) was lower in Mel than in control (P < 0.01). The Tes threshold for cutaneous vasodilation and the slope of cutaneous vascular conductance with respect to Tes were also lower in Mel at both untreated and bretylium-treated sites (P < 0.05). The Tes threshold for the onset of sweating and the Tes for a standard HR were reduced in Mel. The slope of the relationship of HR, but not SR, to Tes was lower in Mel (P < 0.05). These findings suggest that melatonin affects the thermoregulatory control of SkBF during hyperthermia via the cutaneous active vasodilator system. Because control of SR and HR are also modified, a central action of melatonin is suggested.
    MeSH term(s) Body Temperature/drug effects ; Body Temperature/physiology ; Heart Rate ; Hot Temperature ; Humans ; Male ; Melatonin/administration & dosage ; Melatonin/pharmacology ; Skin/blood supply ; Sweating/physiology ; Vasodilation/drug effects ; Vasodilation/physiology
    Chemical Substances Melatonin (JL5DK93RCL)
    Language English
    Publishing date 2006-05-11
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 603839-6
    ISSN 1522-1490 ; 0363-6119
    ISSN (online) 1522-1490
    ISSN 0363-6119
    DOI 10.1152/ajpregu.00117.2006
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  5. Article: Neuropeptide Y antagonism reduces reflex cutaneous vasoconstriction in humans.

    Stephens, Dan P / Saad, Adham R / Bennett, Lee Ann T / Kosiba, Wojciech A / Johnson, John M

    American journal of physiology. Heart and circulatory physiology

    2004  Volume 287, Issue 3, Page(s) H1404–9

    Abstract: Previous studies have provided evidence of a non-noradrenergic contributor to reflex cutaneous vasoconstriction in humans but did not identify the transmitter responsible. To test whether neuropeptide Y (NPY) has a role, in two series of experiments we ... ...

    Abstract Previous studies have provided evidence of a non-noradrenergic contributor to reflex cutaneous vasoconstriction in humans but did not identify the transmitter responsible. To test whether neuropeptide Y (NPY) has a role, in two series of experiments we slowly reduced whole body skin temperature (TSK) from 34.5 to 31.7 degrees C. In protocol 1, Ringer solution and the NPY receptor antagonist BIBP-3226 alone were delivered intradermally via microdialysis. In protocol 2, yohimbine plus propranolol (Yoh + Pro), Yoh + Pro in combination with BIBP-3226, and Ringer solution were delivered to antagonize locally the vasomotor effects of NPY and norepinephrine. Blood flow was measured by laser Doppler flowmetry (LDF). Mean arterial blood pressure (MAP) was monitored at the finger (Finapres). In protocol 1, cutaneous vascular conductance (CVC) fell by 45%, to 55.1 +/- 5.6% of baseline at control sites (P < 0.05). At BIBP-3226-treated sites, CVC fell by 34.1% to 65.9 +/- 5.0% (P < 0.05; P < 0.05 between sites). In protocol 2, during body cooling, CVC at control sites fell by 32.6%, to 67.4 +/- 4.3% of baseline; at sites treated with Yoh + Pro, CVC fell by 18.7%, to 81.3 +/- 4.4% of baseline (P < 0.05 vs. baseline; P < 0.05 vs. control) and did not fall significantly at sites treated with BIBP-3226 + Yoh + Pro (P > 0.05; P < 0.05 vs. other sites). After cooling, exogenous norepinephrine induced vasoconstriction at control sites (P < 0.05) but not at sites treated with Yoh + Pro + BIBP-3226 (P > 0.05). These results indicate that NPY participates in sympathetically mediated cutaneous vasoconstriction in humans during whole body cooling.
    MeSH term(s) Adult ; Arginine/analogs & derivatives ; Arginine/pharmacology ; Blood Vessels/drug effects ; Cold Temperature ; Drug Combinations ; Fingers ; Humans ; Isotonic Solutions ; Male ; Neuropeptide Y/antagonists & inhibitors ; Neuropeptide Y/physiology ; Norepinephrine/antagonists & inhibitors ; Norepinephrine/pharmacology ; Norepinephrine/physiology ; Propranolol/pharmacology ; Reflex/physiology ; Regional Blood Flow/drug effects ; Ringer's Solution ; Skin/blood supply ; Skin/innervation ; Skin Physiological Phenomena ; Skin Temperature ; Sympathetic Nervous System/physiology ; Vasoconstriction/physiology ; Vasoconstrictor Agents/antagonists & inhibitors ; Vasoconstrictor Agents/metabolism ; Vasoconstrictor Agents/pharmacology ; Vasodilator Agents/pharmacology ; Vasomotor System/drug effects ; Vasomotor System/physiology ; Yohimbine/pharmacology
    Chemical Substances BIBP 3226 ; Drug Combinations ; Isotonic Solutions ; Neuropeptide Y ; Vasoconstrictor Agents ; Vasodilator Agents ; Yohimbine (2Y49VWD90Q) ; Ringer's Solution (8026-10-6) ; Arginine (94ZLA3W45F) ; Propranolol (9Y8NXQ24VQ) ; Norepinephrine (X4W3ENH1CV)
    Language English
    Publishing date 2004-05-27
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, P.H.S.
    ZDB-ID 603838-4
    ISSN 1522-1539 ; 0363-6135
    ISSN (online) 1522-1539
    ISSN 0363-6135
    DOI 10.1152/ajpheart.00061.2004
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  6. Article: Evidence for a role for vasoactive intestinal peptide in active vasodilatation in the cutaneous vasculature of humans.

    Bennett, Lee Ann T / Johnson, John M / Stephens, Dan P / Saad, Adham R / Kellogg, Dean L

    The Journal of physiology

    2003  Volume 552, Issue Pt 1, Page(s) 223–232

    Abstract: Active vasodilatation (AVD) in human, non-glabrous skin depends on functional cholinergic fibres but not on acetylcholine (ACh). We tested whether AVD is a redundant system in which ACh and vasoactive intestinal polypeptide (VIP) are co-released from ... ...

    Abstract Active vasodilatation (AVD) in human, non-glabrous skin depends on functional cholinergic fibres but not on acetylcholine (ACh). We tested whether AVD is a redundant system in which ACh and vasoactive intestinal polypeptide (VIP) are co-released from cholinergic nerves. (1) We administered VIP by intradermal microdialysis to four discrete areas of skin in the presence of different levels of the VIP receptor antagonist, VIP(10-28), also delivered by microdialysis. Skin blood flow (SkBF) was continuously monitored by laser Doppler flowmetry (LDF). Mean arterial pressure (MAP) was measured non-invasively and cutaneous vascular conductance (CVC) calculated as LDF/MAP. Subjects were supine and wore water-perfused suits to control whole-body skin temperature (Tsk) at 34 degrees C. Concentrations of 54 microM, 107 microM, or 214 microM VIP(10-28) were perfused via intradermal microdialysis at 2 microl min-1 for approximately 1 h. Then 7.5 microM VIP was added to the perfusate containing VIP(10-28) at the three concentrations or Ringer solution and perfusion was continued for 45-60 min. At the control site, this level of VIP caused approximately the vasodilatation typical of heat stress. All VIP(10-28)-treated sites displayed an attenuated dilatation in response to the VIP. The greatest attenuation was observed at the site that received 214 microM VIP(10-28) (P < 0.01). (2) We used 214 microM VIP(10-28) alone and with the iontophoretically administered muscarinic receptor antagonist atropine (400 microA cm-2, 45 s, 10 mM) in heated subjects to test the roles of VIP and ACh in AVD. Ringer solution and 214 microM VIP(10-28) were each perfused at two sites, one of which in each case was pretreated with atropine. After 1 h of VIP(10-28) treatment, individuals underwent 45-60 min of whole-body heating (Tsk to 38.5 degrees C). VIP(10-28), alone or in combination with atropine, attenuated the increase in CVC during heat stress, suggesting an important role for VIP in AVD.
    MeSH term(s) Adult ; Atropine/pharmacology ; Body Temperature Regulation/physiology ; Cholinergic Fibers/drug effects ; Cholinergic Fibers/physiology ; Female ; Heat Stress Disorders/physiopathology ; Humans ; Laser-Doppler Flowmetry ; Male ; Microdialysis ; Parasympatholytics/pharmacology ; Peptide Fragments/administration & dosage ; Peptide Fragments/physiology ; Skin/blood supply ; Skin/innervation ; Skin Temperature/drug effects ; Skin Temperature/physiology ; Vasoactive Intestinal Peptide/administration & dosage ; Vasodilation/drug effects
    Chemical Substances Parasympatholytics ; Peptide Fragments ; Vasoactive Intestinal Peptide (37221-79-7) ; vasoactive intestinal peptide (10-28) (69856-17-3) ; Atropine (7C0697DR9I)
    Language English
    Publishing date 2003-10-01
    Publishing country England
    Document type Clinical Trial ; Journal Article ; Research Support, U.S. Gov't, P.H.S.
    ZDB-ID 3115-x
    ISSN 1469-7793 ; 0022-3751
    ISSN (online) 1469-7793
    ISSN 0022-3751
    DOI 10.1113/jphysiol.2003.042135
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  7. Article: Sympathetic nonnoradrenergic cutaneous vasoconstriction in women is associated with reproductive hormone status.

    Stephens, Dan P / Bennett, Lee Ann T / Aoki, Ken / Kosiba, Wojciech A / Charkoudian, Nisha / Johnson, John M

    American journal of physiology. Heart and circulatory physiology

    2001  Volume 282, Issue 1, Page(s) H264–72

    Abstract: We tested whether a nonnoradrenergic component of reflex vasoconstriction of skin blood flow (SkBF) is sensitive to female reproductive hormones. Six women taking oral contraceptives underwent whole-body cooling during high-hormone (HH) and low-hormone ( ... ...

    Abstract We tested whether a nonnoradrenergic component of reflex vasoconstriction of skin blood flow (SkBF) is sensitive to female reproductive hormones. Six women taking oral contraceptives underwent whole-body cooling during high-hormone (HH) and low-hormone (LH) phases of oral contraceptive use. SkBF was monitored by laser Doppler flowmetry (LDF) at sites treated by intradermal injection of yohimbine-propranolol (5 mM and 1 mM; YOPR) to block the effects of norepinephrine (NE) or at saline (Sal) control sites. Mean arterial pressure (MAP) was measured with the use of the Penaz method. Cutaneous vascular conductance (CVC = LDF/mean arterial pressure) was expressed as a percentage of baseline. Whole body skin temperature was decreased from 34 to 31 degrees C in HH and LH. In both HH and LH, CVC at Sal-treated sites was reduced during cooling (CVC = 53.1 +/- 8.6% and 54.4 +/- 4.2%, both P < 0.05). In HH, CVC at YOPR sites was reduced during cooling (78.8 +/- 3.6%, P < 0.05). In contrast, CVC at YOPR sites was not reduced significantly during cooling in LH (CVC = 95.9 +/- 2.8%, P > 0.05). Across phases, CVC at YOPR sites during cooling was significantly different (P < 0.05). After cooling, the effects of NE at YOPR sites were completely blocked. These data indicate that a nonnoradrenergic mechanism of reflex cutaneous vasoconstriction is present in women and is associated with reproductive hormone status.
    MeSH term(s) Adult ; Blood Pressure ; Contraceptives, Oral, Combined/pharmacology ; Female ; Humans ; Propranolol/pharmacology ; Regional Blood Flow/physiology ; Skin/blood supply ; Skin Temperature/drug effects ; Skin Temperature/physiology ; Supine Position ; Vasoconstriction/physiology ; Yohimbine/pharmacology
    Chemical Substances Contraceptives, Oral, Combined ; Yohimbine (2Y49VWD90Q) ; Propranolol (9Y8NXQ24VQ)
    Language English
    Publishing date 2001-11-21
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, P.H.S.
    ZDB-ID 603838-4
    ISSN 1522-1539 ; 0363-6135
    ISSN (online) 1522-1539
    ISSN 0363-6135
    DOI 10.1152/ajpheart.2002.282.1.H264
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

To top