Showing 1 – 20 of 2731
Relevance | Newest | Oldest |
  • JAMA April 14, 2015

    Figure 1: Regions of Cerebral Hypoperfusion Following Acute Ischemic Stroke

    MRI indicates magnetic resonance imaging. A, Schematic representation of regions of hypoperfused brain tissue following acute occlusion of the middle cerebral artery. The ischemic core is an area of irreversible ischemia and cell death; ischemic penumbra, potentially salvageable tissue with prompt reperfusion; benign oligemia, decreased perfusion but no infarction risk regardless of treatment. The infarct core can enlarge into the penumbra if reperfusion is not successful. B, Top, Axial diffusion-weighted MRI (DWI) showing a hyperintensity consistent with irreversible ischemia (ischemic core) in the deep perforating territory of the right middle cerebral artery affecting the caudate, internal capsule, and lentiform nucleus. Bottom, Axial perfusion-weighted MRI (PWI) at the same level as the DWI showed a much larger area of hypoperfusion. Perfusion-weighted imaging uses contrast material to estimate cerebral blood flow. The color scale represents mean transit time of a contrast bolus; blue indicates normal transit time and shades of green, yellow, orange, and red indicate delay in transit time (ischemia). The region of the ischemic core as defined in the DWI shows areas of no contrast (black) in the PWI, indicative of irreversible injury. The area with abnormal transit time surrounding the core is considered the ischemic penumbra. These images are from a 49-year-old patient who presented with sudden onset of dysarthria and left hemiparesis. The MRI images were obtained following intravenous recombinant tissue plasminogen activator administered approximately 50 minutes after symptom onset to assess eligibility for mechanical thrombectomy.
  • JAMA January 4, 2006

    Figure 2: Cell Death Pathway of Nitric Oxide (NO), Glyceraldehyde-3-Phosphate Dehydrogenase (GAPDH), and Siah1

    Nitric oxide, a gaseous messenger released in response to cell death stimuli, is produced by the action of nitric oxide synthase (NOS), which uses the amino acid arginine as a substrate. Nitric oxide nitrosylates GAPDH at sulfur residues, and the S-nitrosylated GAPDH binds to and stabilizes the cell death protein Siah1, after which the GAPDH-Siah1 complex enters the nucleus and promotes cell death. Molecules that disrupt the GAPDH-Siah1 interaction, such as deprenyl and TCH346, may prove useful in blocking cell death. NADP indicates nicotinamide adenine dinucleotide phosphate; NADPH, reduced NADP.
  • Messenger Molecules and Cell Death: Therapeutic Implications

    Abstract Full Text
    is expired quiz
    JAMA. 2006; 295(1):81-89. doi: 10.1001/jama.295.1.81
  • JAMA July 21, 1999

    Figure 2: Proposed Pathophysiology of Immunologically Mediated Bone Marrow Failure

    Infection of hematopoietic stem cells by a virus (shown here) or introduction of a drug into hematopoietic stem cells and chemical modification of cell proteins may lead to the production of neoantigens (red squares). As part of this process, normal cell proteins may be overexpressed (brown half circles) or aberrantly expressed (blue triangles), that is, synthesized in cells that normally do not produce them. Antigen-presenting cells (not shown) process the neoantigens and cell surface proteins into peptides and present them via major histocompatibility complex molecules to quiescent T cells. During the normal immune response, activation of T cells that recognize the neoantigens and T cells that recognize the overexpressed and aberrantly expressed cell proteins (self-reactive T cells) leads to immune destruction of target cells by Fas/Fas ligand-mediated apoptosis (nuclear degeneration indicated by interrupted outlines around nuclei followed by cell death indicated by faded cells). In autoimmune disease, after the normal immune response is complete (for example, destruction of infected cells expressing viral proteins), predominantly self-reactive T cells perpetuate tissue destruction. Chronic T-cell attack may favor the emergence of clones of hematopoietic stem cells that are not susceptible to immune cell recognition (as in paroxysmal nocturnal hemoglobinuria [PNH]) or that resist apoptotic cell death (as in myelodysplasia [MDS]).
  • JAMA May 8, 2002

    Figure 2: Cascade of Events Associated With β-Amyloid Generation and Cell Death

    Oligomerization of the β-amyloid peptide initiates oxidative injury, plaque formation (following β-amyloid aggregation), and possibly tangle formation (dashed line). Oxidative injury and inflammation contribute to membrane disruption, degeneration of the neuronal axon, and loss of synapses. Neurodegeneration ensues leading to cell death and neurotransmitter deficits. Apolipoprotein E, α-1-antichymotrypsin, and possibly α-2-macroglobulin contribute to plaque formation.
  • Effect of the Use and Timing of Bone Marrow Mononuclear Cell Delivery on Left Ventricular Function After Acute Myocardial Infarction: The TIME Randomized Trial

    Abstract Full Text
    free access
    JAMA. 2012; 308(22):2380-2389. doi: 10.1001/jama.2012.28726
    Traverse and coauthors for the Cardiovascular Cell Therapy Research Network report on the effect on left ventricular function of the use and timing of bone marrow mononuclear cell delivery after acute myocardial infarction. In an accompanying Editorial, Marbán and Malliaras discuss the mixed results for bone marrow–derived cell therapy for ischemic heart disease.
  • Effect of Transendocardial Delivery of Autologous Bone Marrow Mononuclear Cells on Functional Capacity, Left Ventricular Function, and Perfusion in Chronic Heart Failure: The FOCUS-CCTRN Trial

    Abstract Full Text
    free access
    JAMA. 2012; 307(16):1717-1726. doi: 10.1001/jama.2012.418
    Perin and coauthors, for the Cardiovascular Cell Therapy Research Network, investigated the effects of transendocardial-delivered bone marrow mononuclear cells (BMCs) in 61 patients receiving BMCs and 31 patients receiving placebo who had chronic ischemic heart failure.
  • Effect of Intracoronary Delivery of Autologous Bone Marrow Mononuclear Cells 2 to 3 Weeks Following Acute Myocardial Infarction on Left Ventricular Function: The LateTIME Randomized Trial

    Abstract Full Text
    free access
    JAMA. 2011; 306(19):2110-2119. doi: 10.1001/jama.2011.1670
  • Reducing Sickle Cell Deaths

    Abstract Full Text
    JAMA. 2009; 302(15):1640-1640. doi: 10.1001/jama.2009.1528
  • Predicting Brain Cell Death

    Abstract Full Text
    JAMA. 2001; 285(16):2070-2070. doi: 10.1001/jama.285.16.2070-JQU10003-3-1
  • Association Between Interstitial Lung Abnormalities and All-Cause Mortality

    Abstract Full Text
    free access
    JAMA. 2016; 315(7):672-681. doi: 10.1001/jama.2016.0518

    This study uses data from 4 population cohorts of people with and without chronic obstructive pulmonary disease to investigate associations between interstitial lung abnormalities (identified by computed tomography) and all-cause mortality.

  • Selective Estrogen Receptor Modulators and Prevention of Invasive Breast Cancer

    Abstract Full Text
    JAMA. 2006; 295(23):2784-2786. doi: 10.1001/jama.295.23.jed60037
  • A 62-Year-Old Woman With Chronic Obstructive Pulmonary Disease

    Abstract Full Text
    is expired quiz
    JAMA. 2003; 290(20):2721-2729. doi: 10.1001/jama.290.20.2721
  • Efficacy of Gefitinib, an Inhibitor of the Epidermal Growth Factor Receptor Tyrosine Kinase, in Symptomatic Patients With Non–Small Cell Lung Cancer: A Randomized Trial

    Abstract Full Text
    free access
    JAMA. 2003; 290(16):2149-2158. doi: 10.1001/jama.290.16.2149
  • Association of Blood Transfusion From Female Donors With and Without a History of Pregnancy With Mortality Among Male and Female Transfusion Recipients

    Abstract Full Text
    is active quiz has multimedia
    JAMA. 2017; 318(15):1471-1478. doi: 10.1001/jama.2017.14825

    This cohort study uses data from first-time transfusion recipients to assess the association between red blood cell transfusion from female donors with and without a history of pregnancy and mortality among red blood cell recipients.

  • JAMA October 17, 2017

    Figure: Cumulative Incidence of Death According to Sex of the Transfusion Recipient and Sex and Pregnancy History of the Donor in the Single-Transfusion Cohort

    The single-transfusion cohort consists of all the follow-up time during which patients had received only a single transfusion. Follow-up time was censored at the time this inclusion criterion was violated. Median follow-up for male recipients of red blood cell transfusions exposed to male donors, 16 (interquartile range [IQR], 1-780) days; to female ever-pregnant donors, 12 (IQR, 1-567) days; and to female never-pregnant donors, 14 (IQR, 1-563) days. Median follow-up for female recipients of red blood cell transfusions exposed to male donors, 24 (IQR, 1-846) days; to female ever-pregnant donors, 21 (IQR, 1-584) days; to female never-pregnant donors, 17 (IQR, 1-640) days.
  • JAMA October 17, 2017

    Figure: Cumulative Incidence of Death According to Sex of the Transfusion Recipient and Sex and Pregnancy History of the Donor in the Single-Transfusion Cohort

    The single-transfusion cohort consists of all the follow-up time during which patients had received only a single transfusion. Follow-up time was censored at the time this inclusion criterion was violated. Median follow-up for male recipients of red blood cell transfusions exposed to male donors, 16 (interquartile range [IQR], 1-780) days; to female ever-pregnant donors, 12 (IQR, 1-567) days; and to female never-pregnant donors, 14 (IQR, 1-563) days. Median follow-up for female recipients of red blood cell transfusions exposed to male donors, 24 (IQR, 1-846) days; to female ever-pregnant donors, 21 (IQR, 1-584) days; to female never-pregnant donors, 17 (IQR, 1-640) days.
  • JAMA October 17, 2017

    Figure: Cumulative Incidence of Death According to Sex of the Transfusion Recipient and Sex and Pregnancy History of the Donor in the Single-Transfusion Cohort

    The single-transfusion cohort consists of all the follow-up time during which patients had received only a single transfusion. Follow-up time was censored at the time this inclusion criterion was violated. Median follow-up for male recipients of red blood cell transfusions exposed to male donors, 16 (interquartile range [IQR], 1-780) days; to female ever-pregnant donors, 12 (IQR, 1-567) days; and to female never-pregnant donors, 14 (IQR, 1-563) days. Median follow-up for female recipients of red blood cell transfusions exposed to male donors, 24 (IQR, 1-846) days; to female ever-pregnant donors, 21 (IQR, 1-584) days; to female never-pregnant donors, 17 (IQR, 1-640) days.