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J Rowe

Publications and source records attributed to J Rowe.

At least 73 records · Page 4Linked to original sources

How one New York hospital is moving to head managed care off at the pass. Interview by Jim Montague.

Like tremors before an earthquake hits, managed care and projected cuts in Medicare and Medicaid are shaking up New York even before they arrive. Many of the city's largest hospitals hope to cushion the shock waves from lost referrals for inpatient care by buying primary care providers, though it's likely many of these efforts will be too little, too late. But a handful of New York's providers have been prepping for managed care's growth, allowing them to address it more on their terms. Mount Sinai Medical Center is so confident its advance work will succeed that it actually is adding a few beds, not closing them. John Rowe, M.D., president of the medical center and the Mount Sinai School of Medicine, spoke recently with H&HN staff writer Jim Montague about Mount Sinai's strategies.

Connecticut↗

Constitutive expression of non-bone/liver/kidney alkaline phosphatase in human osteosarcoma cell lines.

Alkaline phosphatase (ALP) plays an important role in bone mineralization; high levels in differentiated osteoblasts allows their identification easily in vitro. It is generally assumed that the activity of ALP in osteosarcoma-derived cell lines commonly used in studies of bone cell biology is exclusively due to the bone/liver/kidney (BLK) isoenzyme. However, we noted that two human osteosarcoma cell lines, U-2 OS and U-393 OS, predominantly expressed a truncated 1.8 kb mRNA for BLK-ALP. This observation stimulated further investigation upon the ability of ALP to form functional protein. We found that, unlike the BLK-ALP of the Saos-2 osteosarcoma cell line, the activity of U-2 OS ALP was thermostable, unaffected by L-homoarginine and levamisole, but inhibited by L-phenylalanine; these properties are characteristic of the placental and/or placental-like (PL-/PL-like ALP) isoenzymes which are 98% homologous at the amino acid level. In the U-393 OS cell line, which expresses the normal-sized 2.5 kb mRNA in substantially higher levels than that produced by U-2 OS cells, the ALP activity had kinetic properties very similar to that produced by the Saos-2 line for all criteria tested. The HOS osteosarcoma cell line (also known as TE-85), which express the normal-sized 2.5 kb BLK-ALP mRNA only, exhibited ALP activity with kinetic properties of both the BLK and PL-/PL-like isoenzymes. The three test lines, U-2 OS, U-393 OS and HOS, produced PL-/PL-like ALP mRNA and protein constitutively, and levels of these increased in cells treated with 1 microM dexamethasone. However, dexamethasone treatment of cells did not alter the types of ALP isoenzyme expressed. Thus our results show that, like Saos-2 cells, U-393 OS cells produce active BLK-ALP exclusively, whereas U-2 OS cells produce PL-/PL-like ALP only, and the HOS cell line produces both. Our findings have important implications for phenotypic characterization of various human osteosarcoma cell lines, and suggest that the production of PL-/PL-like ALP may be a more common occurrence in osteosarcomas than was originally thought.

Alkaline Phosphatase↗

In-vitro secretion of prostanoids by placental villous cytotrophoblasts in pre-eclampsia.

Villous trophoblasts isolated from term placentae of normal pregnancies, and pregnancies complicated by chronic hypertension or pre-eclampsia, were examined over 7 days in primary culture. Low levels of prostaglandin E2 and prostacyclin (measured as 6-keto prostaglandin Fl alpha) were secreted by trophoblast cells from all three clinical groups. Secretion was maximal at day 1 and decreased exponentially thereafter. Thromboxane secretion also fell sequentially from day 1. Thromboxane secretion by pre-eclamptic trophoblasts was three to four times that of cells from normal or chronically hypertensive subjects. Prostanoid secretion by isolated cultured cytotrophoblasts was not dependent on aggregation or morphological alteration, nor related to changes in progesterone or human chorionic gonadotrophin production. Because the local maternal circulation is exposed to substances secreted by this cell population, thromboxane could be the trigger for vasoconstriction and coagulation found within the maternal uteroplacental circulation in pre-eclampsia.

6-Ketoprostaglandin F1 alpha↗

Alteration of in vitro human decidual endothelial cell growth, endothelin-1 and prostaglandin secretion, by growth factors and intracellular calcium.

Endothelial cells isolated from umbilical veins (HUVEC) and from decidual biopsies collected at caesarean section delivery (DEC) from both normal (N DEC) and pre-eclamptic (PE DEC) women, were maintained in culture until passage 2, when the effect on growth of removing heparin/ECGS (endothelial cell growth supplement) from the culture medium was assessed, and the effects of heparin-free incubation and of the Ca2+ ionophore A23187 on endothelin-1, prostacyclin and prostaglandin E2 secretion over a 24 h period were examined. Cell growth slowed significantly in all three cell types in the absence of heparin/ECGS, and cell death occurred in 1/3 samples of HUVEC, 4/6 of N DEC, but 0/2 of PE DEC over 4 days. During the 24 h incubation for prostaglandin in medium without these growth factors, there was further cell death in N DEC. The addition of A23187 to this stress led to a reduction in cell number in both N DEC and HUVEC, and to a lesser extent in PE DEC. Prostaglandin and endothelin-1 levels were higher in the absence of heparin/ECGS in all cell types There was significant suppression of endothelin-1 secretion at 24 h incubation, and stimulation of prostaglandin secretion by A23187. Incubation without heparin/ECGS magnified the effect of A23187 on prostaglandin secretion, although the proportional change was similar if compared to controls without heparin/ECGS. Withdrawal of heparin/ECGS from the medium altered the balance of PGE2/PGI2 secretion by HUVEC, but not DEC. Endothelial cells require the presence of heparin/ECGS for optimum growth and viability, and N DEC are particularly dependent on these growth factors. PE DEC appear relatively 'hardy' in this regard. The addition of a further potentially toxic stimulus may result in cell death, and experiments to be conducted in limited medium must take this into account. There are both qualitative and quantitative differences in the effects of these stimuli on secretion of vasoactive substances, between decidual and umbilical vein endothelial cells.

Calcimycin↗

A source of glycosylated human T-cell lymphotropic virus type 1 envelope protein: expression of gp46 by the vaccinia virus/T7 polymerase system.

Heterologous expression of the human T-cell lymphotropic virus type 1 (HTLV-1) envelope surface glycoprotein (gp46) in a vaccinia virus/T7 polymerase system resulted in the production of authentic recombinant gp46. Five differentially glycosylated forms of the surface envelope protein were produced by this mammalian system, as demonstrated by tunicamycin inhibition of N-glycosylation and N-glycan removal with endoglycosidase H and glycopeptidase F. These studies revealed that all four potential N-glycosylation sites in gp46 were used for oligosaccharide modification and that the oligosaccharides were mannose-rich and/or hybrid in composition. Conformational integrity of the recombinant HTLV-1 envelope protein was determined by the ability to bind to various HTLV-1-infected human sera and a panel of conformational-dependent human monoclonal antibodies under nondenaturing conditions. Furthermore, this recombinant gp46 was recognized by a series of HTLV-2-infected human sera and sera from a Pan paniscus chimpanzee infected with the distantly related simian T-cell lymphotropic virus STLVpan-p. Maintenance of highly conserved conformational epitopes in the recombinant HTLV-1 envelope protein structure suggests that it may serve as a useful diagnostic reagent and an effective vaccine candidate.

Animals↗

Making oneself at home? Examining the nurse-parent relationship.

Current literature concerning parents' involvement with their hospitalised children focuses on the issues of partnership and family-centered care. Relatively few studies address the dynamics of relationships, practice, and the associated issues of responsibility, status and power. Using participant observation within an interpretive framework, this study highlights an inherent paradox in the expectations and role of parents, situated as visitors and partners in caring for their hospitalised child.

Adult↗

Inpatient general medicine is evidence based. A-Team, Nuffield Department of Clinical Medicine.

For many years clinicians have had to cope with the accusation that only 10-20% of the treatments they provide have any scientific foundation. Their interventions, in other words, are seldom "evidence based". Is the profession guilty as charged? In April, 1995, a general medical team at a university-affiliated district hospital in Oxford, UK, studied the treatments given to all 109 patients managed during that month on whom a diagnosis had been reached. Medical sources (including databases) were then searched for randomised controlled trial (RCT) evidence that the treatments were effective. The 109 primary treatments were then classified: 82% were evidence based (ie, there was RCT support [53%] or unanimity on the team about the existence of convincing non-experimental evidence [29%]). This study, which needs to be repeated in other clinical settings and for other disciplines, suggests that earlier pessimism over the extent to which evidence-based medicine is already practised is misplaced.

Clinical Medicine↗

Effect of serum on secretion of prostacyclin and endothelin-1 by decidual endothelial cells from normal and preeclamptic pregnancies.

OBJECTIVE: Increasing circumstantial evidence suggests that the maternal endothelial cell is centrally involved in the syndrome of preeclampsia, and a number of reports have described the presence of a factor(s) that alters endothelial cell function in serum from women with preeclampsia. We have previously described differences between endothelial cells from the decidual vascular bed and those from the umbilical vein. The purposes of this study were (1) to examine the effect of serum from normal and preeclamptic women on secretion of vasoactive substances by maternal decidual endothelial cells, (2) to compare these results with those from umbilical vein endothelial cells, widely used as a surrogate for endothelial cells in general, (3) to compare responses to these sera by decidual endothelial cells from normal and preeclamptic pregnancies, and (4) to determine whether these responses are amplified by preincubation in test sera. STUDY DESIGN: Endothelial cells were isolated from umbilical veins and from decidual biopsy specimens collected at caesarean section delivery, from both normal and preeclamptic women. Cells were maintained in culture until passage 2, when secretion by the three endothelial cell populations of the vasodilator prostacyclin (measured as its stable metabolite, 6-keto-prostaglandin F1 alpha) and the vasoconstrictor endothelin-1 was compared in the presence of serum from preeclamptic or gestational age-matched normal pregnant women. RESULTS: Prostacyclin secretion by all endothelial cell populations was higher in the presence of serum from preeclamptic women than in medium containing serum from gestational age-matched normal pregnant women. Values for endothelin were not significantly different in cells incubated in serum from normal or preeclamptic women. Preincubation of decidual cells from preeclamptic women in test serum, particularly in preeclamptic serum, resulted in more marked stimulation of prostacyclin secretion. CONCLUSIONS: Preeclamptic serum contains a factor(s) that stimulates prostanoid secretion from endothelial cells. This effect was observed in both umbilical vein and decidual cells. Cells from preeclamptic women were more susceptible to perturbation of their secretion by this factor. Serum from preeclamptic women did not specifically affect endothelin-1 secretion.

6-Ketoprostaglandin F1 alpha↗

Secretion of prostaglandins and endothelin-1 by decidual endothelial cells from normal and preeclamptic pregnancies: comparison with human umbilical vein endothelial cells.

OBJECTIVE: An increasing amount of circumstantial evidence points to the maternal endothelial cell as centrally involved in the syndrome of preeclampsia. The purposes of this study were (1) to compare the secretion of vasoactive substances by maternal decidual endothelial cells with that of umbilical vein endothelial cells, widely used as a surrogate for endothelial cells in general, and (2) to compare secretion of the same vasoactive substances by decidual endothelial cells from normal and preeclamptic pregnancies. STUDY DESIGN: Endothelial cells were isolated from umbilical veins and from decidual biopsy specimens collected at cesarean section delivery from both normal and preeclamptic women. Cells were maintained in culture until passage 2, when secretion by the three endothelial cell populations of the vasodilators prostaglandin E2 and prostacyclin and the vasoconstrictor endothelin-1 was examined. In addition to control incubations, their responses to stimulation and suppression of secretion were compared. RESULTS: In control incubations normal decidual endothelial cells secreted lower amounts of prostacyclin, prostaglandin E2, and endothelin than did human umbilical vein endothelial cells. All cell types had qualitatively similar responses to the stimuli used, but quantitatively different responses were noted between human umbilical vein endothelial cells and normal decidual endothelial cells for all metabolites examined. Preeclamptic decidual endothelial cells secreted significantly more prostaglandin E2 than did normal decidual endothelial cells in response to stimulation. CONCLUSIONS: We have delineated levels of secretion of vasoactive substances by human late pregnancy decidual endothelial cells and their responses to manipulation of secretory pathways. There are differences between this endothelial cell population and human umbilical vein endothelial cells (which are widely used as a surrogate for maternal endothelial cells). The differences between normal and preeclamptic decidual endothelial cells in prostaglandin E2 secretion may point to altered regulation of arachidonic acid metabolic pathways in preeclampsia.

Cells, Cultured↗

The immunophenotype of acute promyelocytic leukemia (APL): an ECOG study.

In 452 adult patients with de novo acute myeloid leukemia (AML), a series of 22 monoclonal antibodies was used to identify immunophenotypic characteristics of acute promyelocytic leukemia (APL) as compared to other AMLs (groups FAB M1/M2 and M4/M5). Only those patients with FAB M3 cytology were included in the analysis for which APL was confirmed by the presence of the t(15;17) cytogenetic aberration and the detection of the PML/RAR alpha gene fusion transcript by PCR amplification (35 cases). Significantly fewer APL blast cells were positive for the stem cell antigen, CD34 (p = 0.0001) as well as for HLA-DR (p < 0.0001). With respect to myeloid antigens, APLs less frequently expressed the myelomonocytic antigens, CD11b (p = 0.0001) and CD14 (p = 0.0013), whereas expression of CD33, a pan-myeloid marker, was more frequent in APL (p = 0.0001). CD15, the X-hapten carbohydrate structure (lacto-N-fucopentaose-III), typically expressed at the maturation stage of normal promyelocytes, was found to be sialylated on APL blasts as recognized by differential binding of the anti-CD15 antibodies, VIM-D5 (non-sialylated CD15) and VEP-9 (sialylated CD15). Expression of the T-cell associated CD7 antigen was rarer on APL than non-APL cells (p = 0.0001), as was that of the multidrug resistance P-glycoprotein (p = 0.0038). Marginal correlations existed between antigen profile (particularly CD2) and the type of PML/RAR alpha transcripts. In addition to its unique genotypic features, these data establish APL as a distinct immunophenotypic entity.

Adult↗