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Haire K, Burton C, Park R, Reynolds J, Stewart D, Purushotham AD. Integrated Cancer System: a perspective on developing an integrated system for cancer services in London. LONDON JOURNAL OF PRIMARY CARE 2012; 5:29-34. [PMID: 25949664 PMCID: PMC4413698 DOI: 10.1080/17571472.2013.11493369] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
This article explores the potential for integrated cancer systems to improve the quality of care and deliver cost efficiencies and improve outcomes for cancer patients. Currently, patients in the UK still have poorer survival rates than comparable countries such as Canada, Sweden, Norway and Australia. Improving the quality of cancer services is a key policy objective and cancer is a priority outcome measure in both the NHS and Public Health Outcomes Framework. Evidence suggests that better integrated delivery has the potential to improve the quality and reduce the cost of healthcare, and ultimately improve health outcomes. One of the key themes from the Model of Care for Cancer Services (1) was that cancer services should be commissioned along pathways and that provider networks should be established to deliver care. London has two integrated cancer systems; one covering north central and east London (London Cancer) and the other covering west and south London (London Cancer Alliance). There a number of areas in cancer care that the current model of service provision has failed to adequately address and which have the potential to improve significantly though implementation of integrated services. These include improving early diagnosis, reducing inequalities in access to treatment and outcomes and maximising research and training across the system. Important drivers for the integration of cancer services are strong clinical leadership, shared informatics systems, focusing on quality of services and improving patient experience. Emerging needs of integrated cancer in London are around strengthening the involvement of primary care, public health and the third sector; working to develop sufficient capacity and expertise in primary care and collaborating more closely with commissioners to develop integrated systems.
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Jung MH, Park BL, Lee BC, Ro Y, Park R, Shin HD, Bae JS, Kang TC, Choi IG. Association of CHRM2 polymorphisms with severity of alcohol dependence. GENES BRAIN AND BEHAVIOR 2010; 10:253-6. [PMID: 21176104 DOI: 10.1111/j.1601-183x.2010.00663.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The cholinergic muscarinic 2 receptor (CHRM2) gene has been considered a candidate gene for the alcohol dependence in that it might underpin certain risk factors for this condition. This study examined variations in the CHRM2 between the patients with alcohol dependence and population controls in Korean and explored the associations between CHRM2 polymorphisms and severity of symptoms in the patients with alcohol dependence. One hundred and fifty-five patients with alcohol dependence, defined by the Alcohol Use Disorders Identification Test (AUDIT) and the Alcohol Dependence Scale (ADS) to measure the severity of symptoms, and one hundred and ninety-five population controls were drawn in the study. Three single nucleotide polymorphisms (SNPs) of CHRM2 were genotyped using the TaqMan assay and analyzed with the severity of symptoms of alcohol dependence. We found that although SNP rs324650 showed marginal association with the risk of alcohol dependence (P = 0.03), the significance of the result was not sustained after multiple corrections. SNP rs1824024 was significantly associated with the AUDIT and ADS scores in patients (P = 0.005 and 0.003, respectively). These findings suggested that the muscarinic acetylcholine function might be related not with alcohol dependence itself but with the severity of alcohol dependence in Korean population.
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Davies EA, Linklater KM, Coupland VH, Renshaw C, Toy J, Park R, Petit J, Housden C, Møller H. Investigation of low 5-year relative survival for breast cancer in a London cancer network. Br J Cancer 2010; 103:1076-80. [PMID: 20736945 PMCID: PMC2965868 DOI: 10.1038/sj.bjc.6605857] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2010] [Revised: 07/19/2010] [Accepted: 07/20/2010] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Breast cancer 5-year relative survival is low in the North East London Cancer Network (NELCN). METHODS We compared breast cancer that was diagnosed during 2001-2005 with that in the rest of London. RESULTS North East London Cancer Network women more often lived in socioeconomic quintile 5 (42 vs 21%) and presented with advanced disease (11 vs 7%). Cox regression analysis showed the survival difference (hazard ratio: 1.27, 95% confidence interval (CI): 1.15-1.41) reduced to 1.00 (95% CI: 0.89-1.11) after adjustment for age, stage, socioeconomic deprivation, ethnicity and treatment. Major drivers were stage and deprivation. Excess mortality was in the first year. CONCLUSION Late diagnosis occurs in NELCN.
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Park R, Cresswell A. Spatiotemporal and kinematic comparisons between treadmill and over-ground walking at a self-selected speed. J Sci Med Sport 2010. [DOI: 10.1016/j.jsams.2009.10.398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Kim K, Kim W, Cho J, Park R, Han W, Noh D, Park H, Oh S, Jung Y. 0056 The simplest model for prediction of nonsentinel lymph node status in breast cancer patients with metastatic sentinel lymph nodes. Breast 2009. [DOI: 10.1016/s0960-9776(09)70101-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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McCracken KJ, Owens B, Park R, McNab J. Lack of relationship between either specific weight or presence of the 1B1R gene and nutritive value of wheat in broiler diets. Br Poult Sci 2008; 49:463-74. [PMID: 18704793 DOI: 10.1080/00071660802158365] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
1. A study of the relationship between specific weight (SW) and nutritive value of wheat in diets offered to broilers up to 4 weeks of age was carried out using 10 varieties of wheat grown at three different locations; this gave rise to a range of specific weights from 59 to 76 kg/hl. 2. Because five varieties contained the 1B1R translocation and 5 did not, this allowed the effects of 1B1R on the performance of birds given high concentrations of dietary wheat to be further investigated. 3. The diets, which contained wheat at 744 g/kg with casein (142 g/kg) as the sole protein supplement, were heat-treated and pelleted. They were fed ad libitum to male, Ross broiler chicks from 7 to 28 d, in individual cages in a controlled environment room. 4. A 7 d excreta collection was made from 14 to 21 d for determination of apparent metabolisable energy (AME) content and wheat AME was calculated from the diet values. A separate determination of true metabolisable energy (TME) was undertaken using the method of McNab and Blair (British Poultry Science, 29: 697-707, 1988). 5. Wheat samples were analysed for proximate constituents, starch, total and soluble non-starch polysaccharides (NSP), amino acid content and gross energy and specific weight, thousand grain weight and in vitro viscosity were recorded. They were also subjected to near infrared reflectance spectroscopy (NIRS) with a view to establishing relationships with chemical constituents and performance parameters. 6. At 28 d the birds were humanely killed and in vivo viscosity was determined on the jejunal digesta supernatant. 7. There was quite a narrow range of crude protein content (N x 5.83) across the 30 wheat samples, the means for the three locations (Crossnacreevy, Downpatrick and Limavady, respectively) being 112, 121 and 122 g/kg. Starch contents of individual samples ranged from 604 to 679 g/kg, total NSP from 92.1 to 122.6 g/kg, soluble NSP from 17.6 to 32.6 g/kg and in vitro viscosity from 10.6 to 26.3 cps. 8. There were no significant varietal effects for dry matter intake (DMI), live weight gain (LWG) or gain:feed ratio. Apparent metabolisability of energy (ME:GE) for the diets ranged from 0.738 (Hussar) to 0.778 (Harrier) the effect being significant (P < 0.05) and there was a significant (P < 0.001) relationship (r(2) = 0.46) between ME:GE and gain:feed ratios. Calculated wheat AME for individual varieties ranged from 14.1 to 15.0 MJ/kg DM (P > 0.05). TME values ranged from 16.3 to 16.6 MJ/kg DM (NS). 9. In vivo viscosity ranged from 12.3 (Ritmo) to 23.7 cps (Hussar), the varietal effects being significant (P < 0.001). Viscosity was significantly higher for the 1B1R varieties than for the non-1B1R (22.7 vs 16.3 cps) but there were no significant effects on mean DM intake, LWG, gain:feed, ME:GE, calculated wheat AME, ME:gain (MJ AME per kg gain) or TME. 10. Wheat AME was negatively correlated (P < 0.05) with total NSP (slope -0.035) but was significantly affected by variety, constants ranging from 16.74 to 17.79. For wheat TME there were significant variety*total NSP interactions with slopes ranging from 0.29 to -0.07. There was no significant relationship between wheat AME and soluble NSP and there were significant variety*soluble NSP interactions for TME with slopes ranging from 0.09 to -0.14. 11. Despite the relatively wide range of in vitro viscosity there was no significant correlation of either calculated wheat AME or wheat TME with in vitro viscosity. For TME there were significant variety*viscosity interactions with slopes ranging from 0.21 to -0.13 (P < 0.001). There was also no significant correlation between soluble NSP and in vivo viscosity. 12. AME values for the NIRS calibration set varied from 13.7 to 15.6 MJ/kg and averaged 14.6 MJ/kg, whereas for the validation set, the values ranged from 14.0 to 16.1 MJ/kg with the mean value being 14.7 MJ/kg. The best correlation coefficient (r(2)) of 0.90 was obtained when the calibration sample set was subjected to SMLR using the second-order derivatised data. However, moving to validation, the outcome was extremely poor with 1-VR values being 0.12 and 0.09, respectively, for the external validation and an internal validation subset. 13. In summary, none of the production characteristics showed a good correlation with specific weight. Using the linear estimates for wheat AME and TME the effect of a 10 kg/hl change in SW equates to a 3 or 1.4% change, respectively. The estimate for AME is likely to be a worst-case value due to the high inclusion level of wheat. The range of calculated wheat AME (approximately 1 MJ) across the 30 wheat samples is similar to that seen in previous studies for wheat grown in Northern Ireland and much lower than in some other studies. 14. None of the other parameters examined gave any better relationship with nutritive value (assessed as AME or TME) than SW. This is a disappointing outcome, particularly in view of some previous studies which suggested that in vitro viscosity provides a good prediction of nutritive value.
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Park R, Hong S, Shin J, Doh H, Choi J. BIOCHEMICAL ANALYSIS OF RECOMBINANT FIBRINOGEN AALPHAGLN328PRO; PREVIOUSLY REPORTED AS FIBRINOGEN VARIANT SEOUL II WITH IMPAIRED FIBRIN ALPHA-CHAIN CROSS-LINKING. J Thromb Haemost 2007. [DOI: 10.1111/j.1538-7836.2007.tb02949.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Gladding P, Webster M, Farrell H, Zeng I, Park R, Ruijine N. Non-Steroidal Anti-Inflammatory Drugs Antagonise the Irreversible Antiplatelet Effect of Aspirin. Heart Lung Circ 2007. [DOI: 10.1016/j.hlc.2007.06.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Swartzendruber PC, Jaffe DA, Prestbo EM, Weiss-Penzias P, Selin NE, Park R, Jacob DJ, Strode S, Jaeglé L. Observations of reactive gaseous mercury in the free troposphere at the Mount Bachelor Observatory. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2006jd007415] [Citation(s) in RCA: 132] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Kolts RL, Nelson RS, Park R, Heikenen J. Exploratory laparoscopy for recurrent right lower quadrant pain in a pediatric population. Pediatr Surg Int 2006; 22:247-9. [PMID: 16416280 DOI: 10.1007/s00383-005-1632-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/22/2005] [Indexed: 11/29/2022]
Abstract
Recurrent or chronic abdominal pain can be a challenging problem when conventional diagnostic studies fail to identify the cause. It is estimated that up to one-third of children suffer from abdominal pain, and in this population recurrent pain can be even more challenging. Although recurrent right lower quadrant (RLQ) or periumbilical pain may be attributed to chronic appendicitis, this diagnosis remains controversial. Our aim was to evaluate pediatric patients who had undergone laparoscopic exploration for chronic RLQ abdominal pain to determine their histologic diagnosis, etiology of pain, and contributing factors that may predict a positive outcome. Patients with abdominal pain greater than 1 month in duration who ultimately underwent laparoscopic exploration and appendectomy were included in the study. Patients were excluded if an identified source of pain was discovered during preoperative workup, or if postoperative follow-up was less than 2 years. Intraoperative findings were noted, and all specimens were histologically examined with additional, subsequent independent review. Pertinent findings from preoperative diagnostic tests, mental health history, and pre and postoperative symptomatology were noted. Patient outcomes were recorded at the time of follow-up and after 2 years to assess resolution of their symptoms. Of the 44 patients studied, 31 (70.5%) had partial or complete resolution of symptoms at 2 years. Thirteen (29.5%) continued to have pain. Twenty-eight patients (63.6%) had abnormal histology identified on appendiceal examination, and 14 had other abnormalities found at laparoscopy (31.8%). Eighteen patients were being treated for psychiatric diagnosis, and 21 suffered from chronic headaches. There were no long-term complications from surgery. Long-term follow-up revealed that 70% reported complete or partial relief of their RLQ pain at 2 years. No factors were identified that may be helpful in predicating outcome in this population. While exploration was beneficial for a majority of this population, patients and parents should be warned that this intervention might not provide the relief of symptoms or provide the diagnostic answer to their pain.
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Park R, Stayner L. 346: Search for Thresholds and Other Non-Linearities in the Hexavalent Chromium – Lung Cancer Exposure Response. Am J Epidemiol 2005. [DOI: 10.1093/aje/161.supplement_1.s87a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Hwang S, Park R. P121 The perceived care needs of breast cancer patientsin Korea. Breast 2005. [DOI: 10.1016/s0960-9776(05)80157-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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Kim PI, Bai H, Bai D, Chae H, Chung S, Kim Y, Park R, Chi YT. Purification and characterization of a lipopeptide produced by Bacillus thuringiensis CMB26. J Appl Microbiol 2004; 97:942-9. [PMID: 15479409 DOI: 10.1111/j.1365-2672.2004.02356.x] [Citation(s) in RCA: 143] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIMS To isolate an antagonist for use in the biological control of phytopathogenic fungi including Colletotrichum gloeosporioides, then to purify and characterize the biocontrol agent produced by the antagonist. METHODS AND RESULTS Bacteria that exhibited antifungal activity against the causative agent pepper anthracnose were isolated from soil, with Bacillus thuringiensis CMB26 showing the strongest activity. A lipopeptide produced by B. thuringiensis CMB26 was precipitated by adjusting the pH 2 with 3 n HCl and extracted using chloroform/methanol (2:1, v/v) and reversed-phase HPLC. The molecular weight was estimated as 1447 Da by MALDI-TOF mass spectrometry. Scanning electron and optical microscopies showed that the lipopeptide has activity against Escherichia coli O157:ac88, larvae of the cabbage white butterfly (Pieris rapae crucivora) and phytopathogenic fungi. The lipopeptide had cyclic structure and the amino acid composition was L-Glu, D-Orn, L-Tyr, D-allo-Thr, D-Ala, D-Val, L-Pro, and L-Ile in a molar ratio of 3:1:2:1:1:2:1:1. The purified lipopeptide showed the same amino acid composition as fengycin, but differed slightly in fatty acid composition, in which the double bond was at carbons 13-14 (m/z 303, 316) and there was no methyl group. CONCLUSION A lipopeptide was purified and characterized from B. thuringiensis CMB26 and found to be similar to the lipopeptide fengycin. This lipopeptide can function as a biocontrol agent, and exhibits fungicidal, bactericidal, and insecticidal activity. SIGNIFICANCE AND IMPACT OF THE STUDY Compared with surfactin and iturin, the lipopeptide from B. thuringiensis CMB26 showed stronger antifungal activity against phytopathogenic fungi. This lipopeptide is a candidate for the biocontrol of pathogens in agriculture.
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Widico C, Price D, Park R, Frazee B. Emergency department ultrasonography for the diagnosis of maxillary sinus fluid. Ann Emerg Med 2004. [DOI: 10.1016/j.annemergmed.2004.07.200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Alagappan K, Park R, Kuo T, Donohue B, Naderi S. 1 EVALUATION FOR TETANUS ANTIBODIES IN KOREAN-AMERICANS LIVING IN THE NEW YORK AREA: A PILOT STUDY. J Investig Med 2004. [DOI: 10.1136/jim-52-suppl2-75] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Park R, Kaler KV, Jones T. A Nonequilibrium Statistical Mechanical Calculation of the Surface Conductance of the Electrical Double Layer of Biological Cells and Its Application to Dielectrophoresis. ACTA ACUST UNITED AC 2003. [DOI: 10.1021/j100120a600] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Park R, Rice F, Stayner L, Smith R, Gilbert S, Checkoway H. Exposure to crystalline silica, silicosis, and lung disease other than cancer in diatomaceous earth industry workers: a quantitative risk assessment. Occup Environ Med 2002; 59:36-43. [PMID: 11836467 PMCID: PMC1740205 DOI: 10.1136/oem.59.1.36] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
OBJECTIVES To estimate excess lifetime risk of (a) mortality from lung disease other than cancer (LDOC), and, (b) onset of radiographic silicosis, arising from occupational exposure to respirable crystalline silica dust. METHODS Data from a cohort of California diatomaceous earth mining and processing workers exposed to crystalline silica dust (mainly as cristobalite) were reanalyzed with Poisson regression methods with internal and external adjustments for potential confounding by calendar time, age, smoking, Hispanic ethnicity, and time since first observation. Model fit was evaluated by comparing deviances and fitting cubic spline models. Lifetime risks of death from LDOC and radiographic silicosis were estimated up to age 85 with an actuarial approach accounting for competing causes of death. RESULTS For deaths due to LDOC, a linear relative rate model gave the best fit in Poisson regression analyses. At the mean cumulative exposure of LDOC cases to silica, after adjustment for smoking, the estimated rate ratio was 4.2 (p<0.0001); at the maximum cumulative exposure of cases, the rate ratio was 18.4. The excess lifetime risk for white men exposed to respirable cristobalite dust for 45 years at the current permissible exposure limit (PEL; about 0.05 mg/m(3)) of the Occupational Safety and Health Administration was 54/1000 (95% confidence interval (95% CI) 17 to 150). For 70 incident cases of radiographic silicosis largely manifest before the end of employment, the best fit was also the linear relative rate model, predicting a rate ratio of 25.6 for silicosis at the mean cumulative exposure of the cases (p<0.0001). The excess lifetime risk for silicosis at the current PEL was 75/1000. CONCLUSION Current occupational health standards for crystalline silica permit risks of lung disease other than cancer far in excess of what is usually considered acceptable by the Occupational Safety and Health Administration (a lifetime risk of less than one in a thousand deaths).
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Park R, Wallace MS, Schulteis G. Relative sensitivity to alfentanil and reliability of current perception threshold vs von Frey tactile stimulation and thermal sensory testing. J Peripher Nerv Syst 2001; 6:232-40. [PMID: 11800047 DOI: 10.1046/j.1529-8027.2001.01025.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Recent technological advances claim to allow quantitative measurement of the functional integrity of both large and small diameter sensory nerve fibers using the current perception threshold (CPT) sensory testing device. This device has yet to be validated against the corresponding gold standard references for sensory testing (thermal sensory testing [TST]) and von Frey tactile hair stimulation [VF]) to correlate its evaluation of similar sensory nerve perceptions. A baseline neurosensory examination using the CPT, TST and VF methods was performed on 19 healthy volunteers. Using a randomized, double-blind, placebo-controlled design, each subject received an alfentanil or diphenhydramine (as a placebo control) infusion in separate study sessions. The order of the study sessions was randomized and separated by 1 week. The 3 neurosensory examinations were repeated at 3 different targeted plasma levels of study drug. Changes in neurosensory thresholds were then compared between the 3 methods. All CPT measurements and the cold pain measurement showed a significantly higher degree of variability than the other TST and VF measurements. There appeared to be a correlation between the CPT 5 Hz pain threshold and the TST cold pain and warm sensation; intravenous alfentanil significantly elevated all 3 detection thresholds. In addition, there was no effect of alfentanil on the VF or the CPT 2000 Hz thresholds. However, we did not see the predicted relation between the 250 Hz CPT stimulus and cool sensation. From these studies, there is some evidence that similar fiber tracts may be measured between the CPT, TST, and VF methods, especially with the CPT 5 Hz measures and C-fiber tract activity.
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Kook MS, Sung K, Kim S, Park R, Kang W. Study of retinal nerve fibre layer thickness in eyes with high tension glaucoma and hemifield defect. Br J Ophthalmol 2001; 85:1167-70. [PMID: 11567958 PMCID: PMC1723743 DOI: 10.1136/bjo.85.10.1167] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
AIM To quantitatively evaluate retinal nerve fibre layer (RNFL) difference in areas of apparently normal appearing visual field in eyes with high tension glaucoma (HTG) and hemifield defects using scanning laser polarimetry. METHODS 40 eyes from 40 patients with HTG with superior or inferior hemifield defects based on the Humphrey field analyser (HFA) underwent RNFL thickness measurements. 20 normal eyes from 20 subjects matched in age and refractive error were selected as a control group. The RNFL thickness was measured with a scanning laser polarimeter. Mean RNFL thickness was evaluated in four quadrants (superior, inferior, nasal, and temporal). A superior or inferior quadrant in the defined ring of scanning laser polarimetry corresponds to inferior or superior hemifield in HFA. RESULTS The mean RNFL thickness in the unaffected quadrant (the quadrant corresponding to the hemifield with apparently normal visual field based on HFA) of the HTG group was significantly thinner than the average RNFL thickness of the corresponding quadrant of the control eyes. The RNFL thickness of the unaffected quadrant in the eyes with HTG was reduced and statistically similar to that of the affected quadrant. Symmetry, calculated as the ratio of superior to inferior RNFL thickness, showed no statistical difference between the study and control group. CONCLUSION Changes in RNFL are present in the apparently normal hemifield in the eyes with HTG. The thickness of the RNFL is reduced symmetrically in both superior and inferior quadrants based on the GDx parameters.
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Chirwa S, Mack J, Park R, Dennis K, Aduonum A. An in vivo model for investigating bilateral synaptic plasticity across CA3/CA1 synapses in guinea pig dorsal hippocampus. J Neurosci Methods 2001; 110:25-30. [PMID: 11564521 DOI: 10.1016/s0165-0270(01)00413-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A method is described for concurrent investigation of long-term potentiation (LTP) in the left and right CA1 synapses in dorsal hippocampi in guinea pig in vivo. Briefly, animals are anesthetized with urethane, and small access holes are made in the skull through which electrodes are lowered to stimulate the left CA3 and record from both CA1 regions. Using this animal model, we have found that LTP is produced in both CA1 regions, following conditioning stimulation to the left CA3. However, in some animals LTP occurred in the left CA1 without concomitant synaptic potentiation in the contralateral CA1. We also observed that in some experiments synaptic potentiation in the contralateral CA1, when present, decayed to baseline levels even though LTP persisted in the ipsilateral CA1. To conclude, our data on bilateral LTP demonstrates findings that are best addressed in vivo.
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