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J M Daly

Publications and source records attributed to J M Daly.

At least 55 records · Page 3Linked to original sources
PubMed2000

ErbB2 potentiates breast tumor proliferation through modulation of p27(Kip1)-Cdk2 complex formation: receptor overexpression does not determine growth dependency.

Overexpression of the ErbB2 receptor, a major component of the ErbB receptor signaling network, contributes to the development of a number of human cancers. ErbB2 presents itself, therefore, as a target for antibody-mediated therapies. In this respect, anti-ErbB2 monoclonal antibody 4D5 specifically inhibits the growth of tumor cells overexpressing ErbB2. We have analyzed the effect of 4D5-mediated ErbB2 inhibition on the cell cycle of the breast tumor cell line BT474. 4D5 treatment of BT474 cells resulted in a G(1) arrest, preceded by rapid dephosphorylation of ErbB2, inhibition of cytoplasmic signal transduction pathways, accumulation of the cyclin-dependent kinase inhibitor p27(Kip1), and inactivation of cyclin-Cdk2 complexes. Time courses demonstrated that 4D5 treatment redirects p27(Kip1) onto Cdk2 complexes, an event preceding increased p27(Kip1) expression; this correlates with the downregulation of c-Myc and D-type cyclins (proteins involved in p27(Kip1) sequestration) and the loss of p27(Kip1) from Cdk4 complexes. Similar events were observed in ErbB2-overexpressing SKBR3 cells, which exhibited reduced proliferation in response to 4D5 treatment. Here, p27(Kip1) redistribution resulted in partial Cdk2 inactivation, consistent with a G1 accumulation. Moreover, p27(Kip1) protein levels remained constant. Antisense-mediated inhibition of p27(Kip1) expression in 4D5-treated BT474 cells further demonstrated that in the absence of p27(Kip1) accumulation, p27(Kip1) redirection onto Cdk2 complexes is sufficient to inactivate Cdk2 and establish the G(1) block. These data suggest that ErbB2 overexpression leads to potentiation of cyclin E-Cdk2 activity through regulation of p27(Kip1) sequestration proteins, thus deregulating the G(1)/S transition. Moreover, through comparison with an ErbB2-overexpressing cell line insensitive to 4D5 treatment, we demonstrate the specificity of these cell cycle events and show that ErbB2 overexpression alone is insufficient to determine the cellular response to receptor inhibition.

Antibodies, Monoclonal↗
PubMed2000

Use of multidimensional assessment to provide testimony on behalf of residents in a life-care home.

City administrators challenged a life-care home's tax-exempt status. A successful, empirically-based case was made based on data collected by gerontological nurses using the Iowa Self-Assessment Inventory (ISAI) and related instruments (Mini-Mental State Examination [MMSE], Instrumental Activities of Daily Living Scale [IADLS], and Physical Self-Maintenance Scale [PSMS]) to describe the life-care population. Testimony by gerontological nurses included comparisons between these life-care residents and statewide data on elderly individuals currently residing in nursing homes and in the community. The data they presented showed not only that this life-care home provided a high quality of life, but also saved society substantial amounts of money in government-funded services that would otherwise be provided to residents of this home. The judge ruled in favor of continuing tax-exempt status for this life-care home because credible evidence clearly demonstrated that taxpayer savings from the services provided to life-care home residents and the life-care commitment dramatically outweighed the taxpayer costs associated with lost tax revenues.

Aged↗
PubMed1999

ErbB receptor-induced activation of stat transcription factors is mediated by Src tyrosine kinases.

Epidermal growth factor (EGF) binding to its receptor, ErbB1, triggers various signal transduction pathways, one of which leads to the activation of signal transducer and activator of transcription (Stat) factors. The mechanism underlying ErbB1-induced Stat activation and whether Stats are downstream targets of other ErbB receptors have not been explored. In this report we show that ErbB2, ErbB3, and ErbB4 do not potentiate Stat5 phosphorylation by EGF. However, neu differentiation factor-induced heterodimers of ErbB2 and ErbB4 activated Stat5. In A431 cells, Stat1, Stat3, and Stat5, were constitutively complexed with ErbB1 and rapidly phosphorylated on tyrosine in response to EGF. Neither mutation of the conserved tyrosine residue (Tyr694) nor inactivation of the Stat5a SH2 domain disrupted this association. However, an intact SH2 domain was necessary for EGF-induced Stat5a phosphorylation. In contrast to prolactin, which induced only Tyr694 phosphorylation of Stat5a, EGF promoted phosphorylation on Tyr694 and additional tyrosine residue(s). Janus kinases (Jaks) were also constitutively associated with ErbB receptors and were phosphorylated in response to EGF-related ligands. However, we provide evidence that EGF- and neu differentiation factor-induced Stat activation are dependent on Src but not Jak kinases. Upon EGF stimulation, c-Src was rapidly recruited to Stat/ErbB receptor complexes. Pharmacological Src kinase inhibitors and a dominant negative c-Src ablated both Stat and Jak tyrosine phosphorylation. However, dominant negative Jaks did not affect EGF-induced Stat phosphorylation. Taken together, the experiments establish two independent roles for Src kinases: (i) key molecules in ErbB receptor-mediated Stat signaling and (ii) potential upstream regulators of Jak kinases.

Epidermal Growth Factor↗
PubMed1999

NDF/heregulin-induced cell cycle changes and apoptosis in breast tumour cells: role of PI3 kinase and p38 MAP kinase pathways.

Neu differentiation factor (NDF)/heregulin activates ErbB2 via heterodimerization with the NDF receptors ErbB3 and ErbB4. Cells which express normal levels of these receptors are often growth stimulated by NDF, whereas SKBR3, and other ErbB2-overexpressing breast tumour cells are growth inhibited. We demonstrate here that in SKBR3 cells, NDF induces G1 progression but also causes a G2 delay from day 1 and apoptosis from days 2-3. G1 progression was associated with ErbB2 transactivation of ErbB3 and subsequent stimulation of the phosphatidylinositol 3-kinase (PI3K) pathway whereas apoptosis was dependent on p38 MAPK. Inhibition of ERK1/ERK2 had no effect on cell cycle progression or apoptosis. Activation of ErbB3 and PI3K was also seen with betacellulin (BTC) but not epidermal growth factor (EGF) and correlated with the growth effects of these ligands. All three ligands induced short-term activation of p38 MAPK in a c-Src-dependent manner. However, only NDF caused a second, c-Src-independent increase in p38 MAPK activity which was required for apoptosis.

Antineoplastic Agents↗
PubMed1999

Cyclooxygenase-2 expression is up-regulated in human pancreatic cancer.

A large body of evidence suggests that cyclooxygenase-2 (COX-2) is important in gastrointestinal cancer. The purpose of this study was to determine whether COX-2 was expressed in adenocarcinoma of the human pancreas. Quantitative reverse transcription-PCR, immunoblotting, and immunohistochemistry were used to assess the expression of COX-2 in pancreatic tissue. Levels of COX-2 mRNA were increased by >60-fold in pancreatic cancer compared to adjacent nontumorous tissue. COX-2 protein was present in 9 of 10 cases of adenocarcinoma of the pancreas but was undetectable in nontumorous pancreatic tissue. Immunohistochemical analysis showed that COX-2 was expressed in malignant epithelial cells. In cultured human pancreatic cancer cells, levels of COX-2 mRNA and protein were induced by treatment with tumor-promoting phorbol esters. Taken together, these results suggest that COX-2 may be a target for the prevention or treatment of pancreatic cancer.

Adenocarcinoma↗
PubMed1999

Glucocorticoid blockade does not abrogate tumor-induced cachexia.

Cancer-induced cachexia is a common manifestation observed in patients with malignancies. Elevated levels of circulating glucocorticoids and interleukin-6 (IL-6) have been observed in cancer patients with cachexia and are implicated as major mediators in this process. The purpose of this study was to investigate the role of circulating glucocorticoid levels as primary mediators in cancer-induced cachexia. We evaluated whether inhibition of glucocorticoids with the receptor antagonist RU-486 could abrogate the detrimental wasting of muscle and adipose tissues seen in a well-characterized murine tumor-induced cachexia model. Mice (12/group) were randomized to control, tumor-bearing, control + vehicle, or tumor-bearing + glucocorticoid receptor antagonist groups. Circulating serum glucocorticoid and IL-6 levels were measured in addition to multiple body composition parameters, such as total body weight, lean body mass, and adipose content. The results of this study indicate a significant physiological alteration in the tumor-bearing host that causes severe and detrimental changes in body composition parameters. Regression analysis demonstrated a significant correlation between increased circulating glucocorticoid levels and alterations in body composition parameters. These observed defects were not abrogated with the administration of a glucocorticoid receptor antagonist. We therefore conclude that the untoward effects of tumor-induced cachexia are not mediated primarily by the peripheral effects of high circulating glucocorticoid levels but may involve a complex interaction with IL-6.

Adenocarcinoma↗
PubMed1998

Altered macrophage intracellular signaling induced by protein-calorie malnutrition.

Protein-calorie malnutrition (PCM) contributes to increased morbidity and mortality through impairment of host defense mechanisms and reduced macrophage function. The present study examined alterations in macrophage intracellular signaling associated with the impairment in host defense capabilities. Mice were randomized to either control (regular diet) or protein-free diets (PCM) and pair-fed for 1 week. Following endotoxin stimulation, peritoneal macrophages from PCM mice produce significantly less TNF-alpha and IL-6 product and had significantly less cell-associated IL-6 when compared to macrophages from control mice. Similarly, macrophages from PCM mice had a significant reduction in mRNA levels for both TNF-alpha and IL-6. Other macrophage intracellular signaling mechanisms, such as calcium flux and tyrosine kinase phosphorylation were also altered by PCM. The etiology of PCM-induced defects in macrophage function and intracellular signaling remain unknown but may be related to the neuroendocrine response to PCM.

Animals↗
PubMed1998

The use of tricyclic antidepressants in children and adolescents.

For children and adolescents, TCAs have proven efficacy in the treatment of enuresis, OCD, and ADHD, with less compelling evidence in anxiety and tic disorders and as-yet unproven efficacy in major depression. The TCAs continue to be a valuable second-line treatment in the previously mentioned conditions. Given the possible adverse effects caused by these medications and the individual variability in plasma levels, effective, responsible use of these medications includes careful monitoring by the prescribing clinician.

Adolescent↗
PubMed1998

Choledochal cysts in adults: a report of two cases and review of the literature.

A choledocal cyst is a dilation of some component of the biliary tract that may include both intra- and extra-hepatic sites. They are classified into six types, all of which are relatively rare. Previously, choledochal cysts were treated with biliary-enteric bypass procedures. The current recommendation is to attempt complete excision to minimize the known risk of malignancy and the development of recurrent cholangitis or pancreatitis that may occur in patients with these cystic lesions. Two cases are discussed in which type I choledochal cysts presented. One was removed from a 31-yr-old man who presented with vague abdominal complaints the other from a 32-yr-old man who presented with pancreatitis. The epidemiology, diagnosis, surgical treatment, and risk of cancer in choledochal cysts is described.

Adult↗
PubMed1998

Trauma-induced alterations in macrophage function.

BACKGROUND: The juxtaposition of immune suppression and a hyperactive inflammatory response after injury represents a paradox in immune function. The aim of this study was to evaluate the delayed macrophage hypersecretion of inflammatory mediators in relation to functional macrophage defects. METHODS: BALB/c mice were randomized to control or trauma (femur fracture plus 40% blood volume hemorrhage) groups. One and 7 days after injury, splenic macrophages were isolated and assayed for antigen presentation and the production of inflammatory mediators tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-6, prostaglandin E2, H2O2, and nitric oxide. RESULTS: One day after injury, there were significantly diminished macrophage antigen presentation and decreased mean production of TNF-alpha, IL-6, and H2O2. In contrast, 7 days after injury, splenic macrophages produced significantly increased mean amounts of TNF-alpha, IL-6, prostaglandin E2, H2O2, and nitric oxide, with a persistent functional defect in antigen presentation. CONCLUSIONS: This phasic response to trauma suggests a persistent state of macrophage dysregulation that may help explain the paradox of immune suppression, manifested by functional defects predisposing patients to increased infections, in the setting of inflammatory mediator hypersecretion, predisposing patients to the systemic inflammatory response syndrome/multiple organ dysfunction syndrome.

Animals↗
PubMed1997

Neu differentiation factor induces ErbB2 down-regulation and apoptosis of ErbB2-overexpressing breast tumor cells.

Neu differentiation factor (NDF), a member of the epidermal growth factor (EGF)-related peptide family, activates ErbB2 via heterodimerization with the NDF receptors ErbB3 and ErbB4. In a similar fashion, EGF receptor (EGFR) agonists induce heterodimers of EGFR and ErbB2. In this paper, we show that the ErbB2-overexpressing breast tumor cells SKBR3, AU565, and MDA-MB453 are growth inhibited by NDF. Cells with elevated levels of ErbB2 but little or no NDF receptors (SKOV3 and MDA-MB361) or cells with low levels of ErbB2 (T47D and MCF7) are not growth inhibited. None of the EGFR agonists tested (EGF, beta-cellulin, or heparin-binding EGF) inhibited growth of ErbB2-overexpressing cells. These results suggest that formation of an ErbB2/NDF receptor heterodimer, but not of an ErbB2/EGFR heterodimer, promotes growth inhibition. In addition, NDF caused a down-regulation of ErbB2 but not of ErbB3. The mechanism underlying the inhibitory effect was examined further in SKBR3 cells, which are 95% growth inhibited by NDF. A G2-M arrest is seen 24 h after NDF treatment, and increased apoptosis is detectable from day 2 onward. The results demonstrate for the first time that NDF induces apoptosis of tumor cells overexpressing ErbB2.

Antineoplastic Agents↗
PubMed1997

ErbB-2, the preferred heterodimerization partner of all ErbB receptors, is a mediator of lateral signaling.

We have analyzed ErbB receptor interplay induced by the epidermal growth factor (EGF)-related peptides in cell lines naturally expressing the four ErbB receptors. Down-regulation of cell surface ErbB-1 or ErbB-2 by intracellular expression of specific antibodies has allowed us to delineate the role of these receptors during signaling elicited by: EGF and heparin binding EGF (HB-EGF), ligands of ErbB-1; betacellulin (BTC), a ligand of ErbB-1 and ErbB-4; and neu differentiation factor (NDF), a ligand of ErbB-3 and ErbB-4. Ligand-induced ErbB receptor heterodimerization follows a strict hierarchy and ErbB-2 is the preferred heterodimerization partner of all ErbB proteins. NDF-activated ErbB-3 or ErbB-4 heterodimerize with ErbB-1 only when no ErbB-2 is available. If all ErbB receptors are present, NDF receptors preferentially dimerize with ErbB-2. Furthermore, EGF- and BTC-induced activation of ErbB-3 is impaired in the absence of ErbB-2, suggesting that ErbB-2 has a role in the lateral transmission of signals between other ErbB receptors. Finally, ErbB-1 activated by all EGF-related peptides (EGF, HB-EGF, BTC and NDF) couples to SHC, whereas only ErbB-1 activated by its own ligands associates with and phosphorylates Cbl. These results provide the first biochemical evidence that a given ErbB receptor has distinct signaling properties depending on its dimerization.

Betacellulin↗
PubMed1997

In vivo adenoviral-mediated gene transfer in the treatment of pancreatic cancer.

Gene therapy may allow targeted delivery of tumoricidal drugs to treat pancreatic cancer. Cytosine deaminase (CD) is a bacterial enzyme that converts the nontoxic agent 5-fluorocytosine (5FC) to the active chemotherapeutic agent 5-fluorouracil (5FU). Neoplastic cells induced to express the CD gene treated with 5FC may generate locally high concentrations of 5FU while minimising systemic toxicity. Replication deficient adenovirus vector carrying the CD gene (AdCMV.CD) was tested for therapeutic efficacy against the murine pancreatic carcinoma cell line Pan02. Pan02 cells were infected in vitro with AdCMV.CD or null vector (Ad.-Null) and were examined for expression of CD messenger RNA (mRNA) (Northern blot) and CD enzymatic function (spectrophotometry). mRNA transcripts of the CD gene increased in a dose-dependent manner after infection with AdCMV.CD. Conversion of 5FC to 5FU at a multiplicity of infection (MOI) of 20 was measured to be 51% after a 48-hr incubation. Growth inhibition was measured by MTT assay and thymidine uptake. Pan02 growth in vitro treated with AdCMV.CD and 5FC was inhibited by 80% as compared to cells treated with Ad.Null and 5FC. An in vivo model of pancreatic cancer was established by injecting 2.5 x 10(5) PAN02 cells subcutaneously into the flanks of C57BL/ 6 mice. Seven days later AdCMV.CD was injected into each tumor and 5FC was administered for 10 days. Treatment of mice with AdCMV.CD and 5FC inhibited tumor growth compared to mice who received AdCMV.CD only or 5FC only. These data demonstrate the therapeutic efficacy of an enzyme prodrug strategy in experimental pancreatic cancer.

Adenoviridae↗
PubMed1997

Candida infection following severe trauma exacerbates Th2 cytokines and increases mortality.

Following trauma, there is an increase of Th2 cytokines (IL-4, IL-6, and IL-10) and a decrease in Th1 cytokines (IFN-gamma and IL-2) that may account for impaired cellular immunity. However, the functional significance of a dominant Th2 pattern to the host remains unclear. The aim of this study was to evaluate whether Candida albicans (CA) sepsis in the setting of a Th2 response to trauma leads to increased mortality and to examine the mediators involved. Female BALB/c mice were randomized (12 per group) to receive no injury (C); trauma, consisting of a combined femur fracture and 40% total blood loss (T); no injury plus CA infection (C+CA); and CA infection 1 week following trauma (T+CA). Survival was then followed for 3 weeks. In a separate study, mice were treated as above (5 per group) and sacrificed. Harvested splenocytes were evaluated for concanavalin A-stimulated cytokine production and liver and kidney homogenates were plated to evaluate CA growth per organ and examined histologically. Candida infection at 1 week following trauma resulted in significantly increased mortality compared to infected controls. Furthermore, the Th2 dominant cytokine pattern was significantly augmented in the presence of CA infection in both C+CA and T+CA groups. Additional analysis showed significant growth of CA in liver and kidney homogenates from T+CA compared to C+CA mice. These results suggest that injured and infected mice demonstrate augmentation of Th2 dominant responses above that of injury or infection alone, as well as a decreased ability to clear Candida which may partially explain the increase in mortality observed. Therapies designed to neutralize Th2 cytokines or augment Th1 cytokines may prove beneficial in the setting of sepsis following trauma.

Acute Disease↗
PubMed1997

Surgical aspects of colorectal carcinoma.

Colorectal surgery remains the cornerstone of curative therapy for colorectal carcinoma. The development of new instruments permitting technical advances, however, as well as the advent of effective adjuvant therapies and the progress in staging and early detection, have changed some of the indications for surgery as well as surgical methods. Even so, emphasis has always been placed on thorough preoperative evaluation and staging. This article explores the current state of standard surgical care of the colorectal cancer patient with special attention given to preoperative evaluation, standard and controversial surgical therapies, and postoperative surveillance.

Colectomy↗
PubMed1997

What interventions do nurses use in long-term care?

This study validated that the Nursing Interventions Classification is appropriate for use in long term care. It is comprehensive and supports the interventions nurses need and use in long term care practice. There is a need for additional research to determine its usefulness in other settings and with other patient populations, as well as studies based on practice versus respondent's opinion. For the elderly clients alone, there are many settings in which to verify use of NIC; including residential, assisted living, independent living, intermediate care units, skilled care units, low-stimulus units, hospice, adult day care and the emerging specialty units. An important next step will be to note the similarities and differences of interventions used across these settings to discern practice setting needs.

Adult↗