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Lieb WE, Flaharty PM, Ho A, Sergott RC. Color Doppler imaging of the eye and orbit. A synopsis of a 400 case experience. Acta Ophthalmol 2009:50-4. [PMID: 1332394 DOI: 10.1111/j.1755-3768.1992.tb04924.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Color Doppler imaging (CDI) is a recent advance in ultrasonography that allows simultaneous two-dimensional imaging of structure and blood flow. Doppler information is superimposed in color over a conventional gray-scale ultrasound image. Using this technique we have examined 400 eyes. The central retinal artery, posterior ciliary arteries, ophthalmic artery, the central retinal vein and the vortex veins could be located in all normal eyes. Using the color image as a guide, Doppler spectral analysis is used for quantitative assessment of blood flow velocity in these vessels. We also studied patients with intraocular tumors, arterial and venous retinal occlusions, orbital vascular anomalies and tumors. Color Doppler imaging is a new and promising modality for the study of ocular and orbital hemodynamics.
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Schmitz N, Ziepert M, Nickelsen M, Wolf SP, Truemper L, Loeffler M, Ho A, Metzner B, Rosenwald A, Pfreundschuh M. Mature T-/NK-cell lymphomas: Prognostic factors and treatment outcome of patients treated on studies of the German High-Grade Lymphoma Study Group (DSHNHL). J Clin Oncol 2009. [DOI: 10.1200/jco.2009.27.15_suppl.8564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
8564 Background: T-cell lymphomas represent a heterogeneous group of malignancies difficult to diagnose and to treat. We evaluated patients (pts) diagnosed according to WHO standards and treated on prospective studies of the DSHNHL. Chemotherapy regimens (CHOP-14 and CHOEP) had significantly improved outcomes of patients with aggressive B-NHL. Methods: Between 1993 and 2006 we treated 329 pts with ALK-positive ALCL (73 pts), ALK-negative ALCL (108 pts), PTCL, NOS (68 pts), AITL (28 pts), NK-/T-cell lymphoma (18 pts), and rare T-cell lymphomas on prospective studies. All pts received CHOP ± etoposide (E) every 2 or 3 weeks; in pts <=60 yrs C, H, and E were escalated to further improve outcomes. Results: The majority of pts with ALK-positive ALCL presented with IPI 0, 1 (62%) or IPI 2 (26%) and had an excellent overall survival (OS) of 89 % and event-free survival (EFS) of 75% at 3 yrs. E significantly improved TTTF for pts <=60 yrs (p=0.007). Pts with other histologies did significantly worse (OS 58%, EFS 44 % at 3 yrs). The IPI discriminated between pts with a favorable (IPI 0, 1: OS 73%), moderate (IPI 2: OS 55%), and poor prognosis (IPI 3: OS 35%; IPI 4, 5: OS 19%) at 3 yrs. OS, EFS were significantly better for ALK-positive ALCL but did not significantly differ for pts in other histological subgroups. Neither shortening of the treatment interval (CHOP-14) nor the addition of E (CHOEP-21 or -14) significantly improved outcome of elderly pts. In younger pts (ALK-positive ALCL were excluded) and good-risk disease (LDH <= N) there was a trend for better EFS after the addition of E to CHOP (EFS 63% vs. 48%, p = 0.065). The MegaCHOEP protocol (Schmitz et al., CANCER 2006) failed to improve treatment results for younger pts with poor-risk disease (EFS at 3 yrs: 25.9%, 95% CI: 10.4–41.4); the prospective study comparing MegaCHOEP with CHOEP-14 was stopped for pts with T-cell lymphoma. Conclusions: CHO(E)P results in excellent OS of pts with ALK-positive ALCL and selected pts with other histologies and low IPI. All other pts did poorly; CHOP-14 or the addition of E failed to significantly improve outcomes. Notably, also the MegaCHOEP protocol characterized by repetitive high-dose therapy and ASCT did not result in significant improvement. No significant financial relationships to disclose.
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Gemignani M, Karam A, Hsu M, Patil S, Stempel M, Traina T, Ho A, Cody H, Morrow M. Determinants of outcome in elderly patients with positive sentinel lymph nodes. J Clin Oncol 2009. [DOI: 10.1200/jco.2009.27.15_suppl.614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
614 Background: Older women are less likely to receive standard of care treatment for breast cancer. This undertreatment may be linked to the perception that elderly patients (pts) may not tolerate or derive benefit from treatment that is often viewed as “too toxic.” Methods: From July 1997 to July 2003, 1,470 pts with invasive cancer with positive sentinel lymph nodes (PSLN) by intraoperative frozen section or final pathologic exam by hematoxylin-eosin and/or immunohistochemistry (IHC). We examined sociodemographic, pathologic, and therapeutic variables that affected the outcome of elderly pts ≥70 years old. A comorbidity score was assigned using Adult Comorbidity Evaluation-27 system. Chi-square, Fisher's exact Wilcoxon tests, and multivariate logistic regression analysis were used. Results: The median age was 53 years (range 21–89) and median tumor size 1.6 cm (range 0.1–11). 1,265 (86.1%) pts were <70 years old and 205 (13.9%) pts were ≥70 years old. 183 (12.5%) pts had IHC only PSLN, 1,021 (69.5%) had 1–3 PSLN, and 266 (18%) ≥4 PSLN. Breast conservation therapy (BCT) was performed in 59.7% of pts. Elderly pts were more likely to have moderate to severe comorbidities (46% vs. 11%, p < 0.0001) and BCT (67% vs. 59%, p = 0.026), compared to pts <70 years old. Elderly pts were less likely to undergo completion ALND (73% vs. 89%, p < 0.0001), adjuvant chemotherapy (43% vs. 90%, p < 0.0001) and radiotherapy following BCT (82% vs. 90%) compared to pts <70 years old. The 5-year disease-free survival (DFS) was not significantly different for elderly pts compared to non-elderly pts (87.7% vs. 91.9%, p = 0.21), on the other hand the 5-year overall survival was significantly worse for elderly pts (80.4% vs. 93.2%, p < 0.0001), a difference that was mainly due to a significantly higher 5-year cumulative incidence of death due to other causes (13.2% vs. 1.9%, p < 0.0001). On multivariate analysis, ER or PR positive status, IHC only PSLN and T1 tumors were the only factors independently associated with improved odds of 5-year DFS. Conclusions: Tumor rather than patient factors were the primary determinants of breast cancer outcomes in our cohort of node positive breast cancer pts. Elderly breast cancer pts with an estimated life expectancy beyond 5 years should receive the same standard of care therapy as their younger counterparts. No significant financial relationships to disclose.
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Devidze N, Zhou Y, Ho A, Zhang Q, Pfaff DW, Kreek MJ. Steady-state methadone effect on generalized arousal in male and female mice. Behav Neurosci 2009; 122:1248-56. [PMID: 19045944 DOI: 10.1037/a0013276] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Methadone is widely used in treatment of short-acting opiate addiction. The on-off effects of opioids have been documented to have profound differences from steady-state opioids. The authors hypothesize that opioids play important roles in either generalized arousal (GA) or aversive state of arousal during opioid withdrawal. Both male and female C57BL6 mice received steady-state methadone (SSM) through osmotic pumps at 10 or 20 mg/kg/day, and GA was measured in voluntary motor activity, sensory responsivity, and contextual fear conditioning. SSM did not have any effect on those GA behaviors in either sex. Females had higher activity and less fear conditioning than males. The effects of SSM on stress-responsive orexin gene expression in the lateral hypothalamus (LH) and medial hypothalamus (MH, including perifornical and dorsomedial areas) were measured after the behavioral tests. Females showed significantly lower basal LH (but not MH) orexin mRNA levels than males. A panel of GA stressors increased LH orexin mRNA levels in females only; these increases were blunted by SSM at 20 mg/kg. In summary, SSM had no effect on GA behaviors. In females, SSM blunted the GA stress-induced LH orexin gene expression.
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Whatham A, Zimmermann F, Martinez A, Delgado S, de la Jara PL, Sankaridurg P, Ho A. Influence of accommodation on off-axis refractive errors in myopic eyes. J Vis 2009; 9:14.1-13. [PMID: 19757953 DOI: 10.1167/9.3.14] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Zhang Y, Landthaler M, Schlussman SD, Yuferov V, Ho A, Tuschl T, Kreek MJ. Mu opioid receptor knockdown in the substantia nigra/ventral tegmental area by synthetic small interfering RNA blocks the rewarding and locomotor effects of heroin. Neuroscience 2008; 158:474-83. [PMID: 18938225 DOI: 10.1016/j.neuroscience.2008.09.039] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2008] [Revised: 09/19/2008] [Accepted: 10/13/2008] [Indexed: 10/21/2022]
Abstract
Mu opioid receptors (MOP-r) play an important role in the rewarding and locomotor stimulatory effects of heroin. The aim of the current study was to determine whether infusion of small interfering RNAs (siRNA) targeting MOP-r into the midbrain could knock down MOP-r mRNA and affect heroin-induced locomotor activity or heroin-induced conditioned place preference. Ten-week-old male C57BL/6J mice were surgically implanted bilaterally with guide cannulae directed between the substantia nigra and ventral tegmental area. After 4 days' recovery, mice were infused bilaterally with siRNAs that target the MOP-r (2 mMx0.75 microl/side/day for 3 days) or control siRNA. Seven days after the last infusion, a procedure for conditioned place preference was begun with four heroin (3 mg/kg i.p.) administration sessions alternating with four saline sessions. While heroin induced an increase in locomotor activity in all groups, siRNAs targeting specific regions of MOP-r significantly attenuated this effect. Of particular interest, mice infused with specific siRNAs targeting the MOP-r failed to develop and express conditioned place preference to heroin, or showed a significantly attenuated preference. These alterations in reward-related behaviors are likely due to the reduction in MOP-r mRNA and protein, shown in separate studies by in situ hybridization and autoradiography using the same MOP-r- siRNA infusions. Taken together, these studies demonstrate the utility of siRNA in the neurobiological study of specific components of the reward system and should contribute to the study of other complex behaviors.
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Stephenson JJ, Lewis N, Martin JC, Ho A, Li J, Wu K, Pace L, Eder JP, Schwartz GK. Phase I multicenter study to assess the safety, tolerability, and pharmacokinetics of AZD4877 administered twice weekly in adult patients with advanced solid malignancies. J Clin Oncol 2008. [DOI: 10.1200/jco.2008.26.15_suppl.2516] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Nielsen DA, Ji F, Yuferov V, Ho A, Chen A, Levran O, Ott J, Kreek MJ. Genotype patterns that contribute to increased risk for or protection from developing heroin addiction. Mol Psychiatry 2008; 13:417-28. [PMID: 18195715 PMCID: PMC3810149 DOI: 10.1038/sj.mp.4002147] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2007] [Accepted: 12/06/2007] [Indexed: 11/09/2022]
Abstract
A genome-wide association study was conducted using microarray technology to identify genes that may be associated with the vulnerability to develop heroin addiction, using DNA from 104 individual former severe heroin addicts (meeting Federal criteria for methadone maintenance) and 101 individual control subjects, all Caucasian. Using separate analyses for autosomal and X chromosomal variants, we found that the strongest associations of allele frequency with heroin addiction were with the autosomal variants rs965972, located in the Unigene cluster Hs.147755 (experiment-wise q=0.053), and rs1986513 (q=0.187). The three variants exhibiting the strongest association with heroin addiction by genotype frequency were rs1714984, located in an intron of the gene for the transcription factor myocardin (P=0.000022), rs965972 (P=0.000080) and rs1867898 (P=0.000284). One genotype pattern (AG-TT-GG) was found to be significantly associated with developing heroin addiction (odds ratio (OR)=6.25) and explained 27% of the population attributable risk for heroin addiction in this cohort. Another genotype pattern (GG-CT-GG) of these variants was found to be significantly associated with protection from developing heroin addiction (OR=0.13), and lacking this genotype pattern explained 83% of the population attributable risk for developing heroin addiction. Evidence was found for involvement of five genes in heroin addiction, the genes coding for the mu opioid receptor, the metabotropic receptors mGluR6 and mGluR8, nuclear receptor NR4A2 and cryptochrome 1 (photolyase-like). This approach has identified several new genes potentially associated with heroin addiction and has confirmed the role of OPRM1 in this disease.
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Zhou Y, Cui CL, Schlussman SD, Choi JC, Ho A, Han JS, Kreek MJ. Effects of cocaine place conditioning, chronic escalating-dose "binge" pattern cocaine administration and acute withdrawal on orexin/hypocretin and preprodynorphin gene expressions in lateral hypothalamus of Fischer and Sprague-Dawley rats. Neuroscience 2008; 153:1225-34. [PMID: 18436386 DOI: 10.1016/j.neuroscience.2008.03.023] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2007] [Revised: 02/02/2008] [Accepted: 03/12/2008] [Indexed: 10/22/2022]
Abstract
Recent evidence suggests an important role for hypothalamic orexins/hypocretins in modulation of drug reward and addiction-like behaviors in rodents. Our recent study has shown that the aversive state of arousal during acute morphine withdrawal is associated with increased orexin gene expression in lateral hypothalamus (LH) of Fischer 344 (F344) inbred rats, with no change in the expression of preprodynorphin (ppDyn), a gene co-expressed with LH orexin. Therefore, we determined whether orexin and ppDyn mRNA levels in LH or medial hypothalamus (including perifornical and dorsomedial areas) of F344 or Sprague-Dawley (SD) outbred rats, are altered following: 1) cocaine (10 mg/kg, i.p.) conditioned place preference (CPP); 2) chronic (14 days) cocaine exposure using both "binge" pattern administration in steady-dose (45 mg/kg/day) and escalating-dose (45-90 mg/kg/day) regimens; and 3) acute (1 day) and chronic (14 days) withdrawal from cocaine with opioid receptor antagonist naloxone treatment (1 mg/kg). We found that orexin mRNA levels were decreased after cocaine place conditioning in the LH of SD rats. A decreased LH orexin mRNA level was also observed after chronic escalating-dose cocaine (but not CPP pattern regimen without conditioning, or steady-dose regimen) in both strains. In F344 rats only, acute withdrawal from chronic escalating-dose cocaine administration resulted in increases in both LH orexin and ppDyn mRNA levels, which were unaltered by naloxone or after chronic withdrawal. Our results suggest that (1) alteration of LH orexin gene expression is region-specific after cocaine place conditioning in SD rats and dose-dependent after chronic exposure in both strains; and (2) increased LH orexin and ppDyn gene expressions in F344 rats may contribute to negative affective states in cocaine withdrawal.
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de Melo-Martín I, Ho A. Beyond informed consent: the therapeutic misconception and trust. JOURNAL OF MEDICAL ETHICS 2008; 34:202-5. [PMID: 18316464 DOI: 10.1136/jme.2006.019406] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
The therapeutic misconception has been seen as presenting an ethical problem because failure to distinguish the aims of research participation from those receiving ordinary treatment may seriously undermine the informed consent of research subjects. Hence, most theoretical and empirical work on the problems of the therapeutic misconception has been directed to evaluate whether, and to what degree, this confusion invalidates the consent of subjects. We argue here that this focus on the understanding component of informed consent, while important, might be too narrow to capture the ethical complexity of the therapeutic misconception. We show that concerns about misplaced trust and exploitation of such trust are also relevant, and ought to be taken into account, when considering why the therapeutic misconception matters ethically.
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Geso M, Ackerly T, Brown S, Chua Z, He C, Wong CJ, Powell CE, Ho A, Qiao G, Solomon DH, Patterson W, Droege JM. Determination of dosimetric perturbations caused by aneurysm clip in stereotactic radiosurgery using gel phantoms and EBT-Gafchromic films. Med Phys 2008; 35:744-52. [DOI: 10.1118/1.2828200] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Ho A, Sachidananda R, Carrie S, Neoh C. Quality of life assessment after non-laser endonasal dacryocystorhinostomy. Clin Otolaryngol 2007; 31:399-403. [PMID: 17014449 DOI: 10.1111/j.1749-4486.2006.01278.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE There has been a lack of patient-centred evidence in the Otolaryngology literature, that non-laser endonasal dacryocystorhinostomy improves the quality of life of patients. Many studies demonstrate successful outcomes based on non-validated subjective patient reporting. The aim of this survey was to evaluate the impact of non-laser endonasal dacryocystorhinostomy on the quality of life of patients using a validated questionnaire, the Glasgow Benefit Inventory (GBI). DESIGN Prospective non-randomised case series. SETTING Secondary otorhinolaryngology-ophthalmology centre, single centre. PARTICIPANTS Sixty-five consecutive patients undergoing non-laser endonasal dacryocystorhinostomy were asked to complete a questionnaire at their follow-up clinic appointment. All patients had a minimum of 9 months follow-up. MAIN OUTCOME MEASURES A consultant ophthalmologist reviewed each patient six months after surgery and recorded the outcomes as 'cure', 'better', 'no change' or 'worse'. We defined 'success' as cured or better. 'Failure' suggests no improvement or worsening epiphora. The validated 18-item GBI was used. RESULTS Fully completed questionnaires were received from 55 patients. Mean total GBI scores were +34 for successful non-laser endonasal dacryocystorhinostomy and -19 for failed non-laser endonasal dacryocystorhinostomy (Mann-Whitney z = 3.8, P < 0.001). CONCLUSION Successful non-laser endonasal dacryocystorhinostomy does confer significant quality of life improvement.
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Raj K, John A, Ho A, Chronis C, Khan S, Samuel J, Pomplun S, Thomas NSB, Mufti GJ. CDKN2B methylation status and isolated chromosome 7 abnormalities predict responses to treatment with 5-azacytidine. Leukemia 2007; 21:1937-44. [PMID: 17611569 DOI: 10.1038/sj.leu.2404796] [Citation(s) in RCA: 127] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
5-Azacytidine, a DNA methyl transferase inhibitor, is effective in patients with myelodysplastic syndromes (MDS). Whether responses to 5-Azacytidine are achieved by demethylation of key genes or by cytotoxicity is unclear. Of 34 patients with MDS or acute myeloid leukaemia (AML) treated with 5-Azacytidine, 7 achieved complete remissions (CR) (21%) and 6 achieved haematological improvement. All six had less than 5% bone marrow (BM) blasts at the time of haematological improvements (HI) (2 had pre-existing refractory anaemia (RA), 4 had refractory anaemia with excess blasts (RAEB)). A further patient with RAEB had blast reduction to less than 5% without HI. Five of the seven (71%) complete responders had chromosome 7 abnormalities. BM CR predicted longer overall survival (OS) (median 23 versus 9 months, P=0.015). Bisulphite genomic sequencing (BGS) of the CDKN2B (p15(INK4b)) promoter showed low level, heterogeneous pretreatment methylation (mean 12.2%) in 14/17 (82%) patients analysed. Lower baseline methylation occurred in responders (9.8% versus 16.2% in non-responders P=0.07). No response was seen in patients with >24% methylation, in whom p15(INK4b) mRNA was not expressed. 5-Azacytidine reduced CDKN2B methylation by mean 6.8% in 8/17 (47%) patients, but this did not correlate with response. At 75 mg/m(2), cell death (reduced BM cellularity (P=0.001) and increased apoptosis (P=0.02)) rather than demethylation of CDKN2B correlates with response. Patients with >24% methylation may benefit from alternative dosing or combination strategies.
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Ho A, Tintinalli J, Travers D. Emergency Severity Index for Psychiatric Triage. Acad Emerg Med 2007. [DOI: 10.1197/j.aem.2007.03.1081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Raj K, Ho A, Creamer JD, du Vivier AWP, Salisbury JR, Mufti GJ. Complete response of deep neutrophilic dermatosis associated with myelodysplastic syndrome to 5-azacytidine. Br J Dermatol 2007; 156:1039-41. [PMID: 17408390 DOI: 10.1111/j.1365-2133.2007.07831.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cutaneous manifestations of myelodysplastic syndromes (MDS) may predict disease progression and a poorer prognosis. We describe a patient in whom a deep neutrophilic dermatosis preceded evolution of disease from refractory anaemia to RAEB (refractory anaemia with excess blasts) and resolved completely on treating the disease with 5-azacytidine. The dermatological response was accompanied by complete bone marrow remission and trilineage haematological improvement. We suggest that 5-azacytidine should be considered in the treatment of immune mediated cutaneous manifestations of MDS.
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Ho A, Tintinalli J. Emergency Severity Index for Psychiatric Triage. Acad Emerg Med 2007. [DOI: 10.1197/j.aem.2007.03.1082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Wong CJ, Ackerly T, He C, Patterson W, Powell CE, Ho A, Qiao G, Solomon DH, Meder R, Geso M. High-resolution measurements of small field beams using polymer gels. Appl Radiat Isot 2007; 65:1160-4. [PMID: 17574428 DOI: 10.1016/j.apradiso.2007.04.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2006] [Revised: 04/02/2007] [Accepted: 04/03/2007] [Indexed: 01/27/2023]
Abstract
Small field sizes are increasingly becoming important in radiotherapy particularly since the introduction of intensity-modulated radiation therapy (IMRT) techniques. It is normally a challenging task to reliably measure the delivered dose and to determine its distribution in a medium for such small fields using conventional-type dosimeters such as gas ionisation chambers. Recently, attempts have been made to use films, but they are not tissue equivalent, they measure the dose only in two dimensions and they are not as responsive to radiations. In the present work, polyacrylamide gel (PAG) dosimeters are employed to measure the dose and its distribution in three dimensions for very small field sizes, such as those typically used in stereotactic radiosurgery. Field sizes of 6 x 6 and 18 x 18 mm in width are investigated. The results show an agreement with radiochromic film and ionisation diode measurements, with some variation in measured doses near the edge of the field, where the gel data decreases more rapidly than the other methods.
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Krasniqi F, Ho A, Egerer G. P728 Initial experience with ertapenem in clinical practice: treatment of twenty patients with chemotherapy-induced low-risk febrile neutropenia in an outpatient setting. Int J Antimicrob Agents 2007. [DOI: 10.1016/s0924-8579(07)70569-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Doshi J, Yelnookar S, Goodfellow S, Ho A. Christmas survey: how polite are ENT surgeons? Clin Otolaryngol 2006; 31:557-8. [PMID: 17184471 DOI: 10.1111/j.1365-2273.2006.01281.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Zhang M, Ho A, Hammond E, Sause W, Pilepich M, Shipley W, Sandler H, Khor L, Pollack A, Chakravarti A. 2210. Int J Radiat Oncol Biol Phys 2006. [DOI: 10.1016/j.ijrobp.2006.07.616] [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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Osborne GEN, Pagliuca A, Ho A, du Vivier AWP. Novel treatment of Sézary-like syndrome due to adult T-cell leukaemia/lymphoma with daclizumab (humanized anti-interleukin-2 receptor α
antibody). Br J Dermatol 2006; 155:617-20. [PMID: 16911291 DOI: 10.1111/j.1365-2133.2006.07355.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We describe a patient with erythrodermic adult T-cell leukaemia/lymphoma resistant to multiple systemic therapies who, on the commencement of daclizumab, a humanized anti-interleukin-2 receptor antibody, developed a rapid and sustained complete response with resolution of previously debilitating erythroderma, suggesting significant activity of this agent in this disease process.
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Zhang Y, Svenningsson P, Picetti R, Schlussman SD, Nairn AC, Ho A, Greengard P, Kreek MJ. Cocaine self-administration in mice is inversely related to phosphorylation at Thr34 (protein kinase A site) and Ser130 (kinase CK1 site) of DARPP-32. J Neurosci 2006; 26:2645-51. [PMID: 16525043 PMCID: PMC6675152 DOI: 10.1523/jneurosci.3923-05.2006] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The reinforcing effect of cocaine is associated with increases in dopamine in the striatum. The phosphoprotein DARPP-32 (dopamine- and cAMP-regulated phosphoprotein) has been shown to mediate the intracellular events after activation of dopamine receptors. DARPP-32 is phosphorylated at multiple sites by different protein kinases, but little is known about the functional role of these different sites. Cocaine self-administration and striatal levels of dopamine after acute "binge" cocaine administration were measured in separate lines of mice with alanine mutations introduced into DARPP-32 at either Thr34 (protein kinase A site, Thr34A), Thr75, (cyclin-dependent kinase 5 site, Thr75A), Ser97 (kinase CK2 site, Ser97A), or Ser130 (kinase CK1 site, Ser130A). Acquisition of stable cocaine self-administration required significantly more time in Thr34A-/- mice. Both Thr34A- and Ser130A-DARPP-32 mutant mice self-administered more cocaine than their respective wild-type controls. Also, cocaine-induced increases of dopamine in dorsal striatum were attenuated in the Thr34A- and Ser130A-DARPP-32 phosphomutant mice compared with wild-type mice. Notably, levels of P-Thr34- and P-Ser130-DARPP-32 were reduced after self-administration of cocaine in wild-type mice. Thus, phosphorylation states of Thr34- and Ser130-DARPP-32 play important roles in modulating the reinforcing effects of cocaine.
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Cheung EYN, Ho AYY, Lam KF, Tam S, Kung AWC. Determinants of bone mineral density in Chinese men. Osteoporos Int 2005; 16:1481-6. [PMID: 16133639 DOI: 10.1007/s00198-005-2000-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2004] [Accepted: 10/28/2004] [Indexed: 11/28/2022]
Abstract
Osteoporotic fractures are increasing among Asian populations in both genders, but the risk factors for low bone mineral density (BMD) in Asian men is unclear. To determine the hormonal and lifestyle risk factors for low BMD in Asian men, we studied 407 community-dwelling southern Chinese men aged 50 years and above. Medical history and lifestyle habits were obtained with a structured questionnaire. Dietary calcium and phytoestrogen intake were assessed by a semi-quantitative questionnaire. BMD at the spine and hip were measured by dual-energy X-ray absorptiometry (DXA). Fasting blood was analyzed for 25(OH)D, parathyroid hormone (PTH), total and bioavailable estradiol (bio-E) and testosterone (bio-T). The mean age of the cohort was 68.42+/-10.4 (50-96) years. In the linear regression model, weight, age, body mass index (BMI), bio-E, PTH, cigarette smoking and weight-bearing exercise were significant determinants of total hip BMD. Together they explained 55% of the total variance of hip BMD, with body weight being the most important determining factor. With age and weight adjustment, height, bio-T and flavonoid intake were identified as additional determinants of total hip BMD. Strategies to prevent bone loss and osteoporosis in Asian men should include lifestyle modification and maintenance of hormonal sufficiency.
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Zhou Y, Bendor JT, Yuferov V, Schlussman SD, Ho A, Kreek MJ. Amygdalar vasopressin mRNA increases in acute cocaine withdrawal: evidence for opioid receptor modulation. Neuroscience 2005; 134:1391-7. [PMID: 16039786 DOI: 10.1016/j.neuroscience.2005.05.032] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2005] [Revised: 04/29/2005] [Accepted: 05/16/2005] [Indexed: 11/16/2022]
Abstract
In humans, stress is recognized as a major factor contributing to relapse to drug abuse in abstinent individuals; drugs of abuse themselves or withdrawal from such drugs act as stressors. In the animals, evidence suggests that centrally released arginine vasopressin in both amygdala and hypothalamus plays an important role in stress-related anxiogenic behaviors. The stress responsive hypothalamic-pituitary-adrenal axis is under tonic inhibition via endogenous opioids, and cocaine withdrawal stimulates hypothalamic-pituitary-adrenal activity. The present studies were undertaken to determine whether: (1) 14-day (chronic) "binge" pattern cocaine administration (45 mg/kg/day) or its withdrawal for 3 h (acute), 1 day (subacute) or 10 days (chronic) alters arginine vasopressin mRNA levels in amygdala or hypothalamus; (2) the opioid receptor antagonist naloxone (1mg/kg) alters arginine vasopressin mRNA or hypothalamic-pituitary-adrenal hormonal responses in acute cocaine withdrawal; and (3) there are associated changes of mu opioid receptor or proopiomelanocortin mRNA levels. In amygdala, arginine vasopressin mRNA levels were unchanged after chronic "binge" cocaine, but were increased during acute cocaine withdrawal. Naloxone completely blocked this increase. Neither chronic cocaine nor its acute withdrawal altered amygdalar mu opioid receptor mRNA levels. The increase in amygdalar arginine vasopressin mRNA levels was still observed after subacute withdrawal, but not after chronic withdrawal. Although hypothalamic-pituitary-adrenal tolerance developed with chronic "binge" cocaine, there were modestly elevated plasma adrenocorticotropin hormone levels during acute withdrawal. While naloxone produced modest adrenocorticotropin hormone elevations in cocaine-naïve rats, naloxone failed to elicit an adrenocorticotropin hormone response in cocaine-withdrawn rats. In hypothalamus, neither chronic cocaine nor acute withdrawal altered arginine vasopressin, proopiomelanocortin or mu opioid receptor mRNA levels. These results show that: (1) opioid receptors mediate increased amygdalar arginine vasopressin gene expression during acute cocaine withdrawal, and (2) cocaine withdrawal renders the hypothalamic-pituitary-adrenal axis insensitive to naloxone. Our findings suggest a potential role for amygdalar arginine vasopressin in the aversive consequences of early cocaine withdrawal.
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Zhai G, Ho A, Hammond E, Fontanesi J, Rotman M, Pilepich M, Shipley W, Sandler H, Pollack A, Zhang M, Chakravarti A. Phospho-AKT Expression and Prognosis of Locally Advanced Prostate Cancer: A Study Based on RTOG 8610. Int J Radiat Oncol Biol Phys 2005. [DOI: 10.1016/j.ijrobp.2005.07.546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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