Raul Chavez Valdez

Dr. Raul Chavez Valdez

Department of Pediatrics, Div Neonatal Perinatal Medicine, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
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Research Focus & Metrics

Academic Career Length

22Years (2005-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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9 March 2011 in Annals of Neurology
Verified
Journal Article
Closed access
PDF file
FNFrances Northington
Frances Northington
RVRaul Chavez Valdez
Raul Chavez Valdez
Lee J MartinLee J Martin
Lee J Martin

1 September 2007 in The Journal of Infectious Diseases
Verified
Journal Article
Open access
PDF file
VCVitaliano A. Cama
Vitaliano A. Cama
JRJennifer M. Ross
Jennifer M. Ross
SCSara Crawford
Sara Crawford
VKVivian Kawai
Vivian Kawai
RVRaul Chavez Valdez
Raul Chavez Valdez
Lihua XiaoLihua Xiao
Lihua Xiao
We performed a cross-sectional study to determine the epidemiology of Cryptosporidium in human immunodeficiency virus (HIV)—infected persons at 3 diag

23 June 2010 in Journal of Cerebral Blood Flow & Metabolism
Verified
Journal Article
Open access
FNFrances Northington
Frances Northington
RVRaul Chavez Valdez
Raul Chavez Valdez
EGErnest M Graham
Ernest M Graham
SRSheila Razdan
Sheila Razdan
EGEstelle B Gauda
Estelle B Gauda
LMLee J Martin
Lee J Martin
Necrostatin-1 inhibits receptor-interacting protein (RIP)-1 kinase and programmed necrosis and is neuroprotective in adult rodent models. Owing to the prominence of necrosis and continuum cell death in neonatal hypoxia–ischemia (HI), we tested whether necrostatin was neuroprotective in the developing brain. Postnatal day (P)7 mice were exposed to HI and injected intracerebroventricularly with 0.1 μL of 80 μmol necrostatin, Nec-1, 5-(1H-Indol-3-ylmethyl)-(2-thio-3-methyl) hydantoin, or vehicle. Necrostatin significantly decreased injury in the forebrain and thalamus at P11 and P28. There was specific neuroprotection in necrostatin-treated males. Necrostatin treatment decreased necrotic cell death and increased apoptotic cell death. Hypoxia–ischemia enforced RIP1–RIP3 complex formation and inhibited RIP3–FADD (Fas-associated protein with death domain) interaction, and these effects were blocked by necrostatin. Necrostatin also decreased HI-induced oxidative damage to proteins and attenuated markers of inflammation coincidental with decreased nuclear factor-κB and caspase 1 activation, and FLIP ((Fas-associated death-domain-like IL-1β-converting enzyme)-inhibitory protein) gene and protein expression. In this model of severe neonatal brain injury, we find that cellular necrosis can be managed therapeutically by a single dose of necrostatin, administered after HI, possibly by interrupting RIP1–RIP3-driven oxidative injury and inflammation. The effects of necrostatin treatment after HI reflect the importance of necrosis in the delayed phases of neonatal brain injury and represent a new direction for therapy of neonatal HI.

1 May 2009 in Pediatrics
Verified
Journal Article
Closed access
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AAAlexander G. Agthe
Alexander G. Agthe
GKGeorge R. Kim
George R. Kim
KMKay B. Mathias
Kay B. Mathias
CHCraig W. Hendrix
Craig W. Hendrix
RVRaul Chavez Valdez
Raul Chavez Valdez
EGEstelle B. Gauda
Estelle B. Gauda
OBJECTIVE. To determine if oral clonidine would reduce the duration of opioid detoxification for neonatal abstinence syndrome.METHODS. Infants with intrauterine exposure to methadone or heroin and neonatal abstinence syndrome (2 consecutive modified Finnegan scores of ≥9) were enrolled at 2 hospitals during 2002–2005 and followed until final hospital discharge. All enrolled infants (80) received oral diluted tincture of opium according to a standardized algorithm and were randomly assigned to receive oral clonidine (1 μg/kg every 4 hours) (40 infants) or placebo (40 infants). Primary outcome was duration of opioid therapy. Secondary outcomes included the amount of opium required to control symptoms, number of treatment failures, and differences in blood pressure, heart rate, and oxygen saturation.RESULTS. The median length of therapy was 27% shorter in the clonidine group (11 [95% confidence interval: 8–15 days]) than in the placebo group (15 days [95% confidence interval: 12–17 days]). In the clonidine group, 7 infants required restarting opium after initial discontinuation versus none in the placebo group, with the total length of treatment/observation remaining significantly less in the clonidine group. Higher dosages of opium were required by 40% of the infants in the placebo group versus 20% in the clonidine group. Treatment failures occurred in 12.5% of the infants in the placebo group versus none in the clonidine group. Hypertension, hypotension, bradycardia, or desaturations did not occur in either group. Three infants in the clonidine group died as a result of myocarditis, sudden infant death syndrome, and homicide, all after hospital discharge and before 6 months of age.CONCLUSIONS. In this randomized, double-blind trial, adding clonidine to standard opioid therapy for detoxification from in utero exposure to methadone or heroin reduced the duration of pharmacotherapy for neonatal abstinence without causing short-term adverse cardiovascular outcomes. A larger trial is indicated to determine long-term safety.

1 April 2012 in The Journal of Pediatrics
Verified
Journal Article
Closed access
NRNicola Robertson
Nicola Robertson
STSidhartha Tan
Sidhartha Tan
FGFloris Groenendaal
Floris Groenendaal
FBFrank van Bel
Frank van Bel
SJSandra E. Juul
Sandra E. Juul
CMCarina Mallard
Carina Mallard

1 September 2012 in Neuroscience
Verified
Journal Article
Closed access
RVRaul Chavez Valdez
Raul Chavez Valdez
LML.J. Martin
L.J. Martin
DFD.L. Flock
D.L. Flock
FNFrances Northington
Frances Northington