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author:("Philip, shahi")
1.  Variation in Cerebral Blood Flow Velocity with Cerebral Perfusion Pressure > 40 mm Hg in 42 Children with Severe Traumatic Brain Injury 
Critical care medicine  2009;37(11):2973-2978.
There is no information regarding the relationship between middle cerebral artery flow velocity (Vmca) and cerebral perfusion pressure in pediatric traumatic brain injury (TBI). We determined the incidence of low, normal and high mean Vmca when CPP is > 40 mm Hg in children with severe TBI.
Prospective observational study
Level 1 pediatric trauma center
42 children < 17 years of age with an admission diagnosis of severe TBI (admission Glasgow Coma Scale [GCS] score < 9), TBI on computed tomography (CT) scan, tracheal intubation/mechanical ventilation and intracranial pressure (ICP) monitoring.
Measurements and Main Results
Bilateral middle cerebral arteries were insonated using transcranial Doppler ultrasonography (TCD) to calculate mean Vmca after TBI. Low mean Vmca was defined as Vmca < 2SD and high was defined as mean Vmca > 2SD. Patients were grouped by age (0.8–2.9, 3–5.9, 6–9.9, and 10–16.9 years) and gender to examine the relationship between CPP and low, high or normal mean Vmca. Potential confounders of the relationship between CPP and mean Vmca (ICP, PaCO2, hematocrit [Hct], sedation, fever and impaired autoregulation were examined). Most (33; 79%) children had normal mean Vmca but 4 (9%) patients had low mean Vmca and 5 children (12%) had high mean Vmca despite CPP > 40 mm Hg. There was no difference in potential confounders of the relationship between CPP and mean Vmca except for Hct, which was lower (25 ± 4 [range 21–30]) in children with high mean Vmca. An inverse relationship between mean Vmca and Hct was also found in boys 10–16.9 years.
Both low and/or high mean Vmca occur with CPP > 40 mm Hg in severe pediatric TBI. Of the potential confounders considered, only lower Hct was associated with high mean Vmca.
PMCID: PMC2766437  PMID: 19770734
cerebral blood flow velocity; cerebral perfusion pressure; pediatric trauma; brain injury; blood pressure; middle cerebral artery flow
2.  Hypoxia Markers in Human Osteosarcoma: An Exploratory Study 
Neoplastic cells growing under hypoxic conditions exhibit a more aggressive phenotype by activating a cascade of molecular events partly mediated by hypoxia-inducible transcription factor (HIF-1α) and vascular endothelial growth factor (VEGF). The roles of these markers have been studied previously in several cancer lines. We ascertained the frequency of HIF-1α expression, VEGF expression, the degree of neovascularization, and cell proliferation in osteosarcoma samples. Samples from osteosarcoma patients were assessed for HIF-1α and VEGF protein expression using immunohistochemistry, neovascularization using antibodies for Factor VIII, and cell proliferation using the Ki-67 labeling index. Associations between these parameters and clinical features were examined. HIF-1α staining was positive in 35% of patients and metastases were present in 61% of these HIF-1α-positive patients. VEGF protein expression was detected in 69% of patients, 92% of whom were female. We observed an insignificant trend for a higher frequency of VEGF expression in the high-grade as compared to low-grade osteosarcoma. We observed no association between vascular density and proliferation index and any clinical parameters. We found an association between HIF-1α expression and metastatic disease and between VEGF expression and female gender.
PMCID: PMC2493019  PMID: 18528739

Results 1-2 (2)