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Fortuna J, Bonomo J, Hoffman B, James L, Shutter L, Butler K. QS228. Radiographic Findings in Elderly Patients With Pre-Injury Anti-Platelet Use and Hemorrhagic Brain Injury. J Surg Res 2009. [DOI: 10.1016/j.jss.2008.11.530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Thrower SL, James L, Hall W, Green KM, Arif S, Allen JS, Van-Krinks C, Lozanoska-Ochser B, Marquesini L, Brown S, Wong FS, Dayan CM, Peakman M. Proinsulin peptide immunotherapy in type 1 diabetes: report of a first-in-man Phase I safety study. Clin Exp Immunol 2008; 155:156-65. [PMID: 19040615 DOI: 10.1111/j.1365-2249.2008.03814.x] [Citation(s) in RCA: 127] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Immunotherapeutic strategies under consideration for type 1 diabetes include modification of the autoimmune response through antigen-specific routes. Administration of short peptides representing T cell epitopes targeted by patients with the disease represents one approach. This study evaluated safety and mechanistic outcomes during first-in-man intradermal administration of a human leucocyte antigen-DR4 (HLA-DR4)-restricted peptide epitope of proinsulin (C19-A3). This randomized, open-label study assessed two major theoretical risks of peptide immunotherapy, namely induction of allergic hypersensitivity and exacerbation of the proinflammatory autoimmune response, using clinical assessment and mechanistic assays in vitro. Patients with long-standing type 1 diabetes and HLA-DRB1*0401 genotype received 30 microg (n = 18) or 300 microg (n = 18) of peptide in three equal doses at 0, 1 and 2 months or no intervention (n = 12). Proinsulin peptide immunotherapy in the dosing regimen used is well tolerated and free from risk of systemic hypersensitivity and induction/reactivation of proinsulin-specific, proinflammatory T cells. Peptide-specific T cells secreting the immune suppressive cytokine interleukin (IL)-10 were observed at month 3 in four of 18 patients in the low-dose group (versus one of 12 in the control group; P = not significant). Mean IL-10 response to peptide in the low-dose group increased between 0 and 3 months (P = 0.05 after stimulation with 5 microM peptide in vitro) and then declined to baseline levels between 3 and 6 months (P = 0.01 at 10 microM peptide in vitro). These studies pave the way for future investigations in new-onset patients designed to examine whether proinsulin peptide immunotherapy has beneficial effects on markers of T cell autoimmunity and preservation of beta cell mass.
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James L, Gorwitz RJ, Jones RC, Watson JT, Hageman JC, Jernigan DB, Lord Y, Caballes N, Cortes C, Golash RG, Price JS, Gerber SI. Methicillin-resistant Staphylococcus aureus infections among healthy full-term newborns. Arch Dis Child Fetal Neonatal Ed 2008; 93:F40-4. [PMID: 17412749 DOI: 10.1136/adc.2006.104026] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
OBJECTIVE Methicillin-resistant Staphylococcus aureus (MRSA) strains have emerged in the community, causing disease among healthy people lacking traditional risk factors for MRSA infection. This article describes an outbreak of MRSA among healthy full-term newborns. DESIGN Cases were identified and corresponding medical information collected. Telephone interviews were conducted with mothers of cases and surveillance cultures from mothers and newborns were performed. MRSA isolates were genotyped. SETTING Hospital in Chicago, Illinois, USA. PARTICIPANTS Newborns, their mothers and hospital healthcare workers. INTERVENTION Nursery infection control practices were enhanced. The MRSA-colonised healthcare workers received intranasal mupirocin. MAIN OUTCOME Within 4-23 days of birth, 11 newborns were identified with pustules, vesicles or blisters located on the head, groin, perineum, ears, legs, chin and trunk. All received antimicrobials and recovered without incident. RESULTS None of 432 peripartum women, one of 399 newborns, and two of 135 healthcare workers were nasal MRSA carriers. Available isolates from six patients, two healthcare workers, and one from an MRSA-colonised newborn were similar by pulsed-field gel electrophoresis. Other than contact with the hospital, no common exposures of MRSA transmission were identified. CONCLUSIONS MRSA strains that initially emerged in the community are now causing disease in healthcare settings. Providers should be aware that MRSA can cause skin infections among healthy newborns. Adherence to standard infection control practices is important to prevent transmission of MRSA in nurseries.
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Huffmanm LC, Pandalai PK, Boulton BJ, James L, Starnes SL, Reed MF, Howington JA, Nussbaum MS. Robotic Heller myotomy: a safe operation with higher postoperative quality-of-life indices. Surgery 2007; 142:613-8; discussion 618-20. [PMID: 17950356 DOI: 10.1016/j.surg.2007.08.003] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2007] [Revised: 08/02/2007] [Accepted: 08/18/2007] [Indexed: 01/10/2023]
Abstract
INTRODUCTION Achalasia is a primary motility disorder of the esophagus that is treated most effectively with operative myotomy. Excellent outcomes with laparoscopic myotomy and fundoplication are well known. Heller myotomy utilizing a computer-enhanced (robotic) laparoscopic platform allows for a more precise dissection by utilizing the superior optics of a 3-dimensional camera and greater degrees of freedom provided by robotic instrumentation. How this affects outcome and quality of life is unknown. METHODS We assessed patients' health perceptions using a standardized, validated, health-related, disease-specific quality-of-life metric. Sixty-one consecutive patients undergoing laparoscopic or robotic myotomy over a 6-year period were evaluated prospectively. All operations were performed using intraoperative manometric and endoscopic guidance and all except 5 patients had a fundoplication. The effects of the operation on health-related quality of life were evaluated with the Short Form (SF-36) Health Status Questionnaire and a disease-specific gastroesophageal reflux disease activity (GERD) activity index (GRACI) preoperatively and postoperatively. All patients completed the questionnaire at both time points. Patient scores were compared using 2-way repeated measures analyses of variance followed by the Tukey test. Operative time, estimated blood loss, duration of stay, intraoperative complication, and postoperative complications were analyzed. RESULTS Thirty-seven patients had laparoscopic and 24 patients had robotic Heller myotomy. There was an increase in SF-36 overall evaluation of health postoperatively compared with preoperatively in both groups (P < .05). The robotic myotomy patients had better SF-36 Role Functioning (emotional) and General Health Perceptions (P < .05) compared with the laparoscopic group. The GRACI showed an equivalent improvement in severity of symptoms in both groups (P < .05). Operative time was 287 +/- 9 minutes for laparoscopic cases and 355 +/- 23 minutes for robotic cases. Estimated blood loss and duration of stay were not different between groups. There were 3 operative esophageal perforations (8%) during laparoscopic myotomy and all were repaired immediately. There were no perforations or operative complications in the robotic group. Neither group had any additional complications. CONCLUSIONS Minimally invasive operative myotomy improves functional status and overall evaluation of health in patients with achalasia. Robotic myotomy had no intraoperative esophageal perforations compared with an 8% intraoperative rate during laparoscopic myotomy. Heller myotomy with partial fundoplication using a robotic platform appears to be a more precise and safer operation than laparoscopic myotomy with improved quality-of-life indices postoperatively compared with laparoscopic myotomy with fewer complications; this suggests that, in skilled hands, the robotic platform may be safer, with improved quality-of-life outcomes.
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Arumilli BRB, James L, Bruce C, George H. Slipped upper femoral epiphysis in a child with spondyloepiphyseal dysplasia tarda: a rare coincidence? Hip Int 2007; 17:230-3. [PMID: 19197873 DOI: 10.1177/112070000701700407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We present a report of a child with Spondyloepiphyseal dysplasia tarda (SED) presenting with non-traumatic, insidious onset hip pain with limited internal rotation. Radiographs revealed a left sided stable slipped upper femoral epiphysis (SUFE). To our knowledge an association between these two pathologies has not been reported previously in the literature and hence a tentative commom etiopathogenesis between SED and SUFE is discussed. Patients who have SED often develop hip pain as part of the natural history of the condition. This case highlights the need to be vigilant regarding the potential for SUFE as a cause of hip pain rather than attributing it to the dysplasia itself in these patients.
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James L, Shindo N, Cutter J, Ma S, Chew SK. Public health measures implemented during the SARS outbreak in Singapore, 2003. Public Health 2005; 120:20-6. [PMID: 16297416 DOI: 10.1016/j.puhe.2005.10.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The SARS outbreak hit Singapore between March and May 2003. Public health control measures were applied along three fronts; prevention and control within healthcare settings, community and at the borders. Nosocomial spread composed majority of SARS cases in Singapore. To prevent infection within healthcare facilities, cases were centralized in a SARS-designated hospital, a no-visitors rule was applied and movement of patients and healthcare staff were restricted. For triaging purposes, fever clinics were established. A dedicated ambulance service was used to transport possible cases to the SARS-designated hospital. Hospitals were surveyed for fever clusters. The challenge was to identify cases with atypical presentation. Effective and safe discharge criteria were established from the lessons learnt. To prevent community spread, contacts of cases were stringently traced, quarantined in their homes and monitored daily. For prompt identification of a case and to reduce the time between onset of symptoms and isolation, the Infectious Diseases Act was amended. A large wholesale market closure resulted in massive quarantine thereby limiting the spread of infection. A mass education campaign was implemented in order to educate and raise awareness of the public. At all air, sea and land points-of-entry, exit and entry screening took place that resulted in zero importation and exportation of SARS cases after implementation of screening. Coordinated effort of the cross sectional inter-ministerial collaboration and strong coordination by the Task Force and commitment from different professionals made it possible to conquer the disease.
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Ogilvie G, Knowles L, Wong E, Taylor D, Tigchelaar J, Brunt C, James L, Maginley J, Jones H, Rekart ML. Incorporating a social networking approach to enhance contact tracing in a heterosexual outbreak of syphilis. Sex Transm Infect 2005; 81:124-7. [PMID: 15800088 PMCID: PMC1764664 DOI: 10.1136/sti.2003.009019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
OBJECTIVE This report describes the outcomes of a social networking approach (SNA) in a heterosexually transmitted syphilis epidemic by street nurses in British Columbia, Canada. METHODS Street nurses used SNA interviewing cues, environmental observation, peer outreach, serial interviewing, conducted blood tests, and offered treatment on the street. Rates of cases of syphilis identified by outreach nurses and cases linked to another case were compared before and after adoption of an SNA. RESULTS SNA resulted in a significantly increased proportion of cases identified by the street nurses (p = 0.01) and increased the percentage of cases linked to a previous case (p = 0.03). CONCLUSION This preliminary study confirms that SNA can increase the number of cases and contacts identified in an epidemic of a sexually transmitted disease in a vulnerable, hard to reach population.
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James L, Onambele G, Woledge R, Skelton D, Woods D, Eleftheriou K, Hawe E, Humphries SE, Haddad F, Montgomery H. IL-6?174G/C genotype is associated with the bone mineral density response to oestrogen replacement therapy in post-menopausal women. Eur J Appl Physiol 2004; 92:227-30. [PMID: 15083368 DOI: 10.1007/s00421-004-1092-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/24/2004] [Indexed: 10/26/2022]
Abstract
A reduction in interleukin-6 (IL-6) activity may contribute to the beneficial effects of hormone replacement therapy (HRT) on the menopausal decline in bone mineral density (BMD). We have examined this hypothesis using a genetic strategy. The -174C (rather than G) IL-6 gene variant is associated with lower IL-6 expression. As such, we might anticipate the C allele to be associated with a greater response to HRT. We have tested this hypothesis. Mean three-site [spine (L1-L4), neck of femur, and Ward's triangle] BMD was measured in 65 women in a 1-year randomised controlled trial of HRT with 0.625 mg oestrogen/day and 0.15 mg norgestrel (n=30). Baseline BMD was genotype-independent for both the control and HRT group. In the control group, the percentage change in BMD after 1 year was similar between genotypes (P=0.45). In contrast, in the HRT group, the rise was genotype-dependent. Those homozygous for the G allele showed a 3.62 (2.14)% increase in BMD compared with 10.44 (4.68)% for the C-homozygous group. Heterozygotes had an intermediate BMD increase of 5.6 (2.82)% [ P=0.006 ( P value for interaction between HRT and genotype was 0.04)] Although the study was limited by its small sample size, these are the first data to demonstrate the importance of IL-6 genotype in determining response to oestrogen therapy, rather than its physiological withdrawal.
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Wigington WC, Johnson WD, Cosman C, James L, Gowdy O, Allen O, Edmonson D, Petrini M, Minocha A. 198 DETAILED DESCRIPTION OF IRRITABLE BOWEL SYNDROME IN AFRICAN-AMERICANS VERSUS CAUCASIANS. J Investig Med 2004. [DOI: 10.1136/jim-52-suppl1-751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Wigington WC, Johnson WD, Cosman C, James L, Gowdy O, Allen O, Edmonson D, Petrini M, Minocha A. 75 FIRST DETAILED CHARACTERIZATION OF FUNCTIONAL DYSPEPSIA AMONG AFRICAN-AMERICANS. J Investig Med 2004. [DOI: 10.1136/jim-52-suppl1-628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Wigington WC, Johnson WD, Cosman C, James L, Gowdy O, Allen O, Edmonson D, Petrini M, Minocha A. DETAILED DESCRIPTION OF IRRITABLE BOWEL SYNDROME IN AFRICAN-AMERICANS VERSUS CAUCASIANS. J Investig Med 2004. [DOI: 10.1097/00042871-200401001-00751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Nieh JY, Ni J, James L. Hot plate welding of polypropylene. Part II: Process simulation. POLYM ENG SCI 2004. [DOI: 10.1002/pen.10280] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Fernandez-Twinn DS, Ozanne SE, Ekizoglou S, Doherty C, James L, Gusterson B, Hales CN. The maternal endocrine environment in the low-protein model of intra-uterine growth restriction. Br J Nutr 2003; 90:815-22. [PMID: 13129451 DOI: 10.1079/bjn2003967] [Citation(s) in RCA: 115] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Many adult diseases, including type 2 diabetes, hypertension and cardiovascular disease, are related to low birth weight. The mechanistic basis of this relationship is not known. To investigate the role of fetal undernutrition, we used a rat model of maternal protein restriction in which dams were fed a diet containing 80 g protein/kg (v. 200 g/kg in the control group) throughout gestation and lactation. Offspring were born smaller than controls and in adulthood developed diabetes, hyperinsulinaemia and tissue insulin resistance. To determine possible mechanisms of fetal programming, circulating levels of several hormones were measured in maternal plasma at gestational days 14, 17 and 21 and fetal plasma at gestational day 21. Several differences were noted at day 14, when glucose concentrations in maternal and feto-placental blood were raised significantly (P=0.04 and P=0.0001 respectively); insulin levels in the low-protein (LP) dams were raised (P=0.04), prolactin levels were raised (P=0.047) and progesterone levels were reduced (P=0.02). Circulating 17beta-oestradiol in the LP dams was raised by 35 % over those of the controls from day 17 to day 21 (P=0.008). A significant decrease in maternal leptin levels (P=0.004) was observed at gestation on day 21. Neither oestradiol nor leptin levels were altered in the fetal circulation at day 21. Maternal and fetal corticosterone levels were comparable with control levels, suggesting that they do not initiate the programming effects in this model. Our present results suggest that maternal protein restriction imposes changes in maternal levels of glucose, insulin, prolactin, progesterone, oestradiol and leptin; these changes could influence the programming of eventual adult disease in the developing fetus.
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James L. A memorable lecture: Lessons of yore. West J Med 2002. [DOI: 10.1136/bmj.324.7332.287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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90
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James L, Fong CW, Foong BH, Wee MK, Chow A, Shum E, Chew SK. Hepatitis B Seroprevalence Study 1999. Singapore Med J 2001; 42:420-4. [PMID: 11811609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
Hepatitis B is a disease of public health importance in Singapore. A study was conducted in 1999 to estimate the overall and gender-, age- and ethnic-specific prevalence of hepatitis B surface antigen (HBsAg), hepatitis B e antigen (HBeAg) and antibody to hepatitis B surface antigen in the Singapore population. A cross-sectional sample of the Singapore population constituting 4,698 Singapore residents aged 18-69 years was surveyed. This was the first time a large-scale study has been conducted to assess the hepatitis B seroprevalence rates in the Singapore population. The overall prevalence of the HBsAg in the general population was estimated to be about 4%. About 13% of the HBsAg carriers were also HBeAg positive. Only about 40% of the population had immunity to hepatitis B virus either through immunisation or from previous exposure to the virus. There was still a large proportion (60%) of the population who had no immunity, especially the younger age group of 18-29 years where only 28% had immunity. There is a need to strengthen the hepatitis B immunisation programme to reach out to those who have no immunity, especially the young adults.
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Choe JM, Kothandapani R, James L, Bowling D. Autologous, cadaveric, and synthetic materials used in sling surgery: comparative biomechanical analysis. Urology 2001; 58:482-6. [PMID: 11549510 DOI: 10.1016/s0090-4295(01)01205-5] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVES To compare the biomechanical properties of allografts, autografts, and synthetic materials used in sling surgery using the Instron tensinometer. METHODS The sling grafts we studied consisted of autologous tissues (dermis, rectus fascia, and vaginal mucosa), cadaver tissues (decellularized dermis and freeze-dried, gamma-irradiated fascia lata), and synthetics (Gore-Tex and polypropylene mesh). The sling grafts were constructed into two types of slings: full strip sling (FSS) versus patch suture sling (PSS). The slings were loaded onto the Instron tensinometer and uniaxially loaded in tension until failure. From the load deformation curve, the mechanical properties of the sling grafts were compared. RESULTS A total of 140 sling grafts were analyzed. In rank order for the FSSs, cadaver allografts had the strongest tensile strength followed by the synthetics and autologous tissues (P <0.05). The tensile strength of the FSSs was greater than for the PSSs for all groups (P </=0.001). In rank order for the PSSs, the synthetics and dermal tissues (autograft and allograft) had the highest tensile strength followed by cadaver fascia lata, rectus fascia, and vaginal mucosa (P <0.05). CONCLUSIONS The tensile strength of the FSS was greater than that of the PSS for the autograft, allograft, and synthetic tissues. The autograft and allograft tissues were significantly weaker as a PSS. The synthetics were more durable as a PSS compared with the organic tissues. When a PSS is constructed from autograft and allograft tissues, the risk of suture pull-through and recurrent stress incontinence must be considered.
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Gottschlich MM, Mayes T, James L, Khoury J, Warden GD. Hypovitaminosis D in Pediatric Burn Patients. ACTA ACUST UNITED AC 2001. [DOI: 10.1097/00004630-200103002-00032] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Ashar HR, James L, Gray K, Carr D, McGuirk M, Maxwell E, Black S, Armstrong L, Doll RJ, Taveras AG, Bishop WR, Kirschmeier P. The farnesyl transferase inhibitor SCH 66336 induces a G(2) --> M or G(1) pause in sensitive human tumor cell lines. Exp Cell Res 2001; 262:17-27. [PMID: 11120601 DOI: 10.1006/excr.2000.5076] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
SCH 66336 is a potent farnesyl transferase inhibitor (FTI) in clinical development. It efficiently prevents the membrane association of H-ras, but not K- or N-ras. Yet, in soft agar, it reverts the anchorage-independent growth of human tumor cell lines (hTCLs) harboring H-ras, K-ras, and N-ras mutations, implying that blocking farnesylation of proteins besides ras may be responsible for this effect. Experiments show that SCH 66336 altered the cell cycle distribution of sensitive human tumor cells in two distinct ways. Most sensitive hTCLs accumulated in the G(2)-->M phase after the FTI treatment, but those with an activated H-ras accumulated in G(1) phase, suggesting that the biological effects induced by FTIs in cells with an activated H-ras are distinct from other sensitive cells. A careful genotypic comparison of the hTCLs revealed that those cells with wild-type p53 are especially sensitive to the FTIs. In these cells p53 and its downstream target gene p21(Cip1) are induced after treatment with SCH 66336 for 24 h. These data suggest that cell cycle effects, either G(1) or G(2)-->M accumulation, and p53 status are important for mediating the effects of FTIs on tumor cells.
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Ingram AJ, James L, Cai L, Thai K, Ly H, Scholey JW. NO inhibits stretch-induced MAPK activity by cytoskeletal disruption. J Biol Chem 2000; 275:40301-6. [PMID: 10984494 DOI: 10.1074/jbc.m007018200] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mesangial cells (MC) grown on extracellular matrix protein-coated plates and exposed to cyclic strain/relaxation proliferate and produce extracellular matrix protein, providing an in vitro model of signaling in stretched MC. Intracellular transduction of mechanical strain involves mitogen-activated protein kinases, and we have shown that p42/44 mitogen-activated protein kinase (extracellular signal-regulated kinase (ERK)) is activated by cyclic strain in MC. In vivo studies show that increased production of nitric oxide (NO) in the remnant kidney limits glomerular injury without reducing glomerular capillary pressure, and we have observed that NO attenuates stretch-induced ERK activity in MC via generation of cyclic guanosine monophosphate (cGMP). Accordingly, we sought to determine whether NO affects strain-induced ERK activity after strain and how this is mediated. Strain-induced ERK activity was dependent on time and magnitude of stretch and was maximal after 10 min at -27 kilopascals. Actin cytoskeleton disruption with cytochalasin D abrogated this. The non-metabolizable cGMP analogue 8-bromo cyclic GMP (8-Br-cGMP) dose-dependently attenuated strain-induced ERK activity. Cytoskeletal stabilization with jasplakinolide prevented this inhibitory effect of 8-Br-cGMP. Cyclic strain increased nuclear translocation of phospho-ERK by immunofluorescent microscopy, again attenuated by 8-Br-cGMP. Jasplakinolide prevented the inhibitory effect of 8-Br-cGMP on activated ERK nuclear translocation after strain. Strain increased ERK-dependent AP-1 nuclear protein binding, which was attenuated by cytochalasin D and 8-Br-cGMP. These data indicate that cGMP can inhibit cyclic strain-induced ERK activity, nuclear translocation, and AP-1 nuclear protein binding. Cytoskeletal disruption leads to the same effect, whereas cytoskeleton stabilization reverses the effect of 8-Br-cGMP. Thus, NO inhibits strain-induced ERK activity by cytoskeletal destabilization.
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Stickgold R, James L, Hobson JA. Visual discrimination learning requires sleep after training. Nat Neurosci 2000; 3:1237-8. [PMID: 11100141 DOI: 10.1038/81756] [Citation(s) in RCA: 422] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Gearhart MM, Luchette FA, Proctor MC, Lutomski DM, Witsken C, James L, Davis K, Johannigman JA, Hurst JM, Frame SB. The risk assessment profile score identifies trauma patients at risk for deep vein thrombosis. Surgery 2000; 128:631-40. [PMID: 11015097 DOI: 10.1067/msy.2000.108224] [Citation(s) in RCA: 114] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND The identification of trauma patients at risk for the development of deep venous thrombosis (DVT) at the time of admission remains difficult. The purpose of this study is to validate the risk assessment profile (RAP) score to stratify patients for DVT prophylaxis. METHODS All patients admitted from November 1998 thru May 1999 were evaluated for enrollment. We prospectively assigned patients as low risk or high risk for DVT using the RAP score. High-risk patients received both pharmacologic and mechanical prophylaxis. Low-risk patients received none. Surveillance duplex Doppler scans were performed each week of hospitalization or if symptoms developed. Hospital charges for prophylaxis were used to determine the savings in the low-risk group. Statistical differences between the risk groups for each factor of the RAP and development of DVT were determined by the chi-squared test, with significance at a probability value of less than .05. RESULTS There were 102 high-risk (64%) and 58 low-risk (36%) individuals studied. Eleven of the high-risk group (10.8%) experienced the development of DVT (asymptomatic, 64%). None of the low-risk group was diagnosed with DVT. Five of the 16 RAP factors were statistically significant for DVT. Eliminating prophylaxis and Doppler scans in low-risk patients resulted in a total savings of $18,908 in hospital charges. CONCLUSIONS The RAP score correctly identified trauma patients at increased risk for the development of DVT. Despite prophylaxis, the high-risk group warrants surveillance scans. Withholding prophylaxis in low-risk patients can reduce hospital charges without risk.
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Ingram AJ, James L, Ly H, Thai K, Scholey JW. Stretch activation of jun N-terminal kinase/stress-activated protein kinase in mesangial cells. Kidney Int 2000; 58:1431-9. [PMID: 11012878 DOI: 10.1046/j.1523-1755.2000.00305.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Mesangial cells (MCs) grown on extracellular matrix (ECM)-coated plates and exposed to cyclic stretch/relaxation proliferate and produce ECM protein, suggesting that this may be a useful in vitro model for MC behavior in response to increased physical forces. The induction of c-fos in response to MC stretch has been shown. Stimuli that lead to c-fos induction pass through mitogen-activated protein (MAP) kinase pathways. We have seen early activation of jun N-terminal kinase/stress-activated protein kinase (SAPK/JNK) in MCs exposed to cyclic stretch. Accordingly, we studied SAPK/JNK activation in stretched MCs and the downstream consequences of this signaling. METHODS MCs (passages 5 to 10) cultured on type 1 collagen-coated, flexible-bottom plates were exposed to 2 to 60 minutes of cyclic strain (60 cycles per minute) by generation of vacuums of -10 to -27 kPa, inducing approximately 16 to 28% maximum elongation in the diameter of the surfaces. Control MCs were grown on coated rigid bottom plates. Protein levels (by Western blot) and activity assays for SAPK/JNK were performed under these conditions. We observed marked activation at -18 kPa and above and at two minutes, and then we studied activation mechanisms under these conditions. Nuclear protein binding to activator protein-1 (AP-1) consensus sequences was also examined. The role of calcium was studied with EGTA and BAPTA-AM to chelate extra- and intracellular calcium, respectively. Protein kinase C (PKC) was down-regulated by incubation with phorbol ester (PMA) for 24 hours prior to stretch. In unstretched MCs, A23187 was used as a calcium ionophore, and PKC was up-regulated with PMA application for 30 minutes to determine the effects on SAPK/JNK. Nuclear protein binding to AP-1 was also determined under these conditions. The effects of stretch, acute PMA, and A23187 on fibronectin mRNA levels were studied using reverse transcriptase-polymerase chain reaction (RT-PCR). RESULTS Cyclic strain/relaxation led to increased SAPK/JNK activity only at two minutes and -18 kPa and above. The activation of SAPK/JNK was dependent on intracellular calcium, with BAPTA-AM almost completely abrogating the response to stretch. EGTA was without effect. Down-regulation of PKC also led to a diminution of activity. In static cells, the calcium ionophore A23187 increased SAPK/JNK activity, and this was potentiated by acute PMA. Stretch, acute PMA, and A23187 all increased nuclear protein binding to AP-1 consensus sequences. mRNA levels for fibronectin were increased by stretch in MCs and by PMA and A23187 in static MCs. No change was observed in the amount of SAPK/JNK protein present in stretched MCs by Western blot. CONCLUSIONS Stretch leads to early activation of SAPK/JNK in MCs. This is dependent on intracellular calcium and PKC and can be replicated by activation of these stimuli in static MCs. A downstream induction of nuclear protein binding to AP-1 consensus sequences was seen in a pattern that was completely concordant with the SAPK/JNK induction.
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Ashar HR, James L, Gray K, Carr D, Black S, Armstrong L, Bishop WR, Kirschmeier P. Farnesyl transferase inhibitors block the farnesylation of CENP-E and CENP-F and alter the association of CENP-E with the microtubules. J Biol Chem 2000; 275:30451-7. [PMID: 10852915 DOI: 10.1074/jbc.m003469200] [Citation(s) in RCA: 262] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Human tumor cell lines that are sensitive to the effects of farnesyl transferase inhibitors accumulate in G(2) --> M (except for cells with an activated Ha-ras that accumulate in G(1)). A search for CAAX box proteins from Swiss-Prot revealed more than 300 peptides. Of these, the centromeric proteins CENP-E and CENP-F are preferentially expressed during mitosis and are implicated as mediators of the G(2) --> M checkpoint. Experiments performed here show that peptides from the COOH-terminal CAAX box of CENP-E and CENP-F are substrates for farnesyl transferase but not geranylgeranyl transferase-I. Although both proteins are prenylated in the human tumor cell line DLD-1, their prenylation is completely inhibited by the farnesyl transferase inhibitor, SCH 66336. Immunohistochemical data with the lung carcinoma cell line, A549, showed that preventing the farnesylation of CENP-E and CENP-F by treatment with the farnesyl transferase inhibitor SCH 66336 does not affect their localization to the kinetochores. However, the presence of farnesyl transferase inhibitors alters the association between CENP-E and the microtubules. Our results imply that the inhibition of CENP-E farnesylation results in the alteration of the microtubule-centromere interaction during mitosis and results in the accumulation of cells prior to metaphase.
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Ingram AJ, James L, Ly H, Thai K, Cai L, Scholey JW. Nitric oxide modulates stretch activation of mitogen-activated protein kinases in mesangial cells. Kidney Int 2000; 58:1067-77. [PMID: 10972671 DOI: 10.1046/j.1523-1755.2000.00264.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND In vivo, intraglomerular hypertension results in resident cell hypertrophy, proliferation and matrix protein production, leading to glomerulosclerosis. Mesangial cells (MCs) exposed to in vitro stretch also proliferate and produce matrix. We have shown activation of Jun N-terminal kinase/stress-activated protein kinase (SAPK) and p42/44 mitogen-activated protein kinase (MAPK) in stretched MCs and have also demonstrated that L-arginine decreases resident cell proliferation and protects against glomerulosclerosis in remnant kidney glomeruli, presumably by increasing nitric oxide (NO) production. Consequently, we studied whether NO could affect SAPK and p42/44 MAPK activation in stretched MCs. METHODS MCs (passages 5 to 10) cultured on type 1 collagen-coated, flexible-bottom plates were exposed to 0 to 30 minutes of cyclic strain (60 cycles per minute) by computer-driven generation of vacuum of -27 kPa, inducing 28% elongation in the diameter of the surface. Control MCs were grown on coated, flexible-bottom plates. Protein levels (by Western blot) and activity assays for SAPK/JNK and p42/44 MAPK were performed under these conditions. As maximal activation was at 10 minutes, with decay by 30 minutes, the effect of NO on kinase activation was studied at 0, 2, 5, and 10 minutes by preincubation with 70 micromol/L s-nitroso-n-acetylpenicillamine (SNAP; an NO donor) or 1 mmol/L 8-bromo cyclic guanosine monophosphate (8-bromo-cGMP). Downstream events in response to stretch and NO were studied at the time of maximal response (10 minutes) by examining nuclear translocation of SAPK with immunofluorescence microscopy and transcription factor activator protein-1 nuclear protein binding by gel mobility shift assay. The effect of kinase inhibition by NO donors on MC proliferation was studied by Western blotting for proliferating cell nuclear antigen (PCNA). RESULTS Cyclic MC stretch led to prompt SAPK and p42/44 MAPK activation, which was maximal at 10 minutes. Preincubation with either SNAP or 8-bromo-cGMP decreased this by 50 and 70%, respectively (N = 4), suggesting that the effect of NO was through cGMP generation. Nuclear translocation of both phosphorylated kinases was seen after 10 minutes of stretch and was largely prevented by 8-bromo-cGMP. Increased DNA binding of activator protein-1 proteins was observed in the nuclei of stretched MCs at 10 minutes by mobility shift assay (N = 4), which was also largely prevented by 8-bromo-cGMP. Stretch increased PCNA expression by MCs, and this was inhibited by 8-bromo-cGMP. CONCLUSIONS Stretch-induced activation of SAPK and p42/44 MAPK in MCs can be inhibited by NO. The effect of NO is mediated by the generation of cGMP. These mechanisms may be responsible, at least in part, for the protective effect of NO in animal models of glomerular injury characterized by glomerular capillary hypertension.
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Ingram AJ, James L, Thai K, Ly H, Cai L, Scholey JW. Nitric oxide modulates mechanical strain-induced activation of p38 MAPK in mesangial cells. Am J Physiol Renal Physiol 2000; 279:F243-51. [PMID: 10919842 DOI: 10.1152/ajprenal.2000.279.2.f243] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Mesangial cells (MC), grown on extracellular matrix (ECM) protein-coated plates and stretched, proliferate and produce ECM, recapitulating in vivo responses to increased glomerular capillary pressure (Pgc). Transduction of strain involves mitogen-activated protein kinases (MAPK), and we have shown that p38 MAPK is activated by strain in MC. Because in vivo studies show that nitric oxide (NO) in the remnant kidney limits glomerular injury without reducing Pgc, we studied whether NO attenuated stretch-induced p38 activation in MC. Increasing p38 activation occurred with increasing stretch, maximally at 10 min at -27-kPa vacuum. Cyclic strain increased nuclear translocation of phosphorylated p38 by immunofluorescent microscopy and nuclear protein binding to nuclear factor-kappaB (NF-kappaB) consensus sequences by mobility shift assay. Both events were largely abrogated by the p38 inhibitor SB-203580. The NO donors 3-morpholinosydnonimine, S-nitroso-N-acetylpenicillamine, and 8-bromoguanosine 3',5'-cyclic monophosphate, a stable cGMP analog, prevented p38 activation and nuclear translocation. Thus strain induces p38 activity and translocation to the nucleus and p38-dependent increases in nuclear protein binding to NF-kappaB. This pathway is attenuated by the NO donors or a cGMP analog.
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