Hypertension: Jaffe A

Anonymous00047, Fitzgerald DA, Massie RJ, Nixon GM, Jaffe A, Wilson A, Landau LI, Twiss J, Smith G, Wainwright C, Harris M. · Department of Respiratory Medicine, The Children's Hospital at Westmead, Sydney, NSW, Australia. · Med J Aust. · Pubmed #19012558 links to  free full text

Abstract: Chronic neonatal lung disease (CNLD) is defined as a supplemental oxygen requirement beyond 36 weeks' postmenstrual age, with more severely affected infants requiring oxygen beyond a full-term-equivalent age. Low-flow supplemental oxygen facilitates discharge from hospital of infants with CNLD who develop hypoxia in air. There is a lack of data on the most appropriate minimum mean target oxygen saturation (Spo(2)) level. Reflecting a variety of clinical practices and infant comorbidities (frequency of oxygen desaturation, presence of pulmonary hypertension, retinopathy of prematurity, and adequacy of growth), the minimum mean target range for Spo(2) during overnight oximetry should be 93%-95%. The effect of supplemental oxygen on carbon dioxide retention should be considered before deciding on an oxygen flow. Most infants with CNLD are not ready for discharge until their supplemental oxygen requirement is < or = 0.5 litres per minute delivered through a nasal cannula. The safety of short-term disconnection from supplemental oxygen should be assessed before discharge. Assessment of oxygenation during sleep with continuous overnight oximetry or polysomnography is recommended when weaning infants from supplemental oxygen. Discontinuation of oxygen therapy is based on clinical assessments and documentation of adequate oxygenation in room air. There is limited objective evidence on which to base recommendations.

Limor R, Weisinger G, Gilad S, Knoll E, Sharon O, Jaffe A, Kohen F, Berger E, Lifschizt-Mercer B, Stern N. · Institute of Endocrinology, Department of Pathology, Tel Aviv-Souraski Medical Center, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel. · Hypertension. · Pubmed #11641300 links to  free full text

Abstract: The lipoxygenase pathway has been implicated in the growth, migration, and contraction of vascular smooth muscle cells (VSMCs). However, the precise type of lipoxygenase present in the vascular wall has not been characterized. In this study, we used a specific reverse-transcriptase polymerase chain reaction method with 2 sets of specific primers on total RNA and polyA (+)RNA of normal human VSMCs prepared from umbilical artery. Two forms of platelet-type 12-lipoxygenase mRNA were present in human VSMCs: the already published form cloned from human erythroleukemia cells and a variant form of platelet-type 12-lipoxygenase, which includes 2 additional sequences consistent with the 2 introns (D and E). This novel form of 12-lipoxygenase poly A (+)RNA was downregulated by lipopolysaccharide (10 ug/ml) and upregulated by epidermal growth factor (100 ng/ml) but was not affected by angiotensin II (10(-7) mol/l). We developed a rabbit anti-human platelet-type 12-lipoxygenase polyclonal antibody directed against a 24-amino acid peptide encoded within exon 4. Western immunoblotting of protein extracted from VSMCs and umbilical artery and platelet extract with this antibody showed a coordinate 110-kDa protein and the already-described 70-kDa band detected in platelets and cord homogenate. Another 120-kDa protein was consistently detected in cord extracts but not in platelet or VSMC homogenates. The immunohistochemistry study performed with the same antibody showed extensive cytoplasmic staining of VSMCs. The specific role of these different forms of platelet-type 12-lipoxygenase is subject to further investigation.