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Park S, Koo J, Park HS, Kim JH, Choi SY, Lee JH, Park BW, Lee KS. Expression of androgen receptors in primary breast cancer. Ann Oncol 2009; 21:488-492. [PMID: 19887463 DOI: 10.1093/annonc/mdp510] [Citation(s) in RCA: 257] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND To investigate the clinicopathological significance of androgen receptor (AR) expression in primary breast cancers. PATIENTS AND METHODS We evaluated AR using immunohistochemistry from 413 whole sections from January 2008 to March 2009 and analyzed the relationship between AR and clinicopathological parameters. Tumors with >/=10% nuclear-stained cells were considered to be positive for AR. The differences among variables were calculated by chi-square test. RESULTS The expression rate of AR was 72.9% higher than those of estrogen receptors (ER) and progesterone receptors. AR expression was significant in patients with no elevated preoperative serum cancer antigen 15-3 levels, smaller tumor size, lower histologic grade and hormone receptor-positive and non-triple-negative breast cancer. However, AR expression was observed in 35% of triple-negative cancers. Metaplastic, medullary and mucinous types of carcinomas showed less AR expression. In the ER-negative subgroup, AR was significantly correlated with human epidermal growth factor receptor type 2 (HER-2) overexpression. CONCLUSIONS AR is expressed in a significant number of breast cancers and is associated with lower tumor burden and favorable differentiation. There are many issues to be further investigated such as whether AR is an independent prognostic factor, whether it is a therapeutic target for the triple-negative breast cancers and whether it is associated with HER-2 signaling in ER-negative tumors.
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Research Support, Non-U.S. Gov't |
16 |
257 |
2
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Koo J. Population-based epidemiologic study of psoriasis with emphasis on quality of life assessment. Dermatol Clin 1996; 14:485-96. [PMID: 8818558 DOI: 10.1016/s0733-8635(05)70376-4] [Citation(s) in RCA: 250] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
With the changing health care scene in the United States, it is important to have up-to-date epidemiological data with regard to the prevalence of psoriasis in the United States. It is also becoming more important to develop a psychometric instrument that is useful in assessing quality of life issues among psoriasis patients. The Psoriasis Disability Index, which was developed in England, may not be optimally applicable in assessing quality of life issues among psoriasis patients seen by American dermatologists. In this article, the latest nationwide population-based epidemiologic data on psoriasis are presented, along with the use of a new psychometric questionnaire that emphasizes the assessment of quality of life rather than disability.
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29 |
250 |
3
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Goodwin PJ, Ennis M, Pritchard KI, McCready D, Koo J, Sidlofsky S, Trudeau M, Hood N, Redwood S. Adjuvant treatment and onset of menopause predict weight gain after breast cancer diagnosis. J Clin Oncol 1999; 17:120-9. [PMID: 10458225 DOI: 10.1200/jco.1999.17.1.120] [Citation(s) in RCA: 238] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
PURPOSE Weight gain is common during the first year after breast cancer diagnosis. In this study, we examined clinical factors associated with body size at diagnosis and weight gain during the subsequent year. PATIENTS AND METHODS An inception cohort of 535 women with newly diagnosed locoregional breast cancer underwent anthropometric measurements at baseline and 1 year. Information was collected on tumor- and treatment-related variables, as well as diet and physical activity. RESULTS Mean age was 50.3 years; 57% of women were premenopausal. Mean baseline body mass index (weight [kg] divided by height [m] squared) was 25.5 kg/m2. Overall, 84.1% of the patients gained weight. Mean weight gain was 1.6 kg (95% confidence interval, 1.2 to 1.9 kg), 2.5 kg (95% confidence interval, 1.8 to 3.2 kg) in those receiving chemotherapy, 1.3 kg (95% confidence interval, 0.7 to 1.8 kg) in those receiving tamoxifen only, and 0.6 kg (95% confidence interval, 0.01 to 1.3 kg) in those receiving no adjuvant treatment. Menopausal status at diagnosis (P = .02), change in menopausal status over the subsequent year (P = .002), axillary nodal status (P = .009), and adjuvant treatment (P = .0002) predicted weight gain in univariate analysis. In multivariate analysis, onset of menopause and administration of chemotherapy were independent predictors of weight gain (all P < or = .05). Caloric intake decreased (P < .01) and physical activity increased (P < .05) during the year after diagnosis; these factors did not explain the observed weight gain. CONCLUSION Weight gain is common after breast cancer diagnosis; use of adjuvant chemotherapy and onset of menopause are the strongest clinical predictors of this weight gain.
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4
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Salamon N, Kung J, Shaw SJ, Koo J, Koh S, Wu JY, Lerner JT, Sankar R, Shields WD, Engel J, Fried I, Miyata H, Yong WH, Vinters HV, Mathern GW. FDG-PET/MRI coregistration improves detection of cortical dysplasia in patients with epilepsy. Neurology 2009; 71:1594-601. [PMID: 19001249 DOI: 10.1212/01.wnl.0000334752.41807.2f] [Citation(s) in RCA: 201] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE Patients with cortical dysplasia (CD) are difficult to treat because the MRI abnormality may be undetectable. This study determined whether fluorodeoxyglucose (FDG)-PET/MRI coregistration enhanced the recognition of CD in epilepsy surgery patients. METHODS Patients from 2004-2007 in whom FDG-PET/MRI coregistration was a component of the presurgical evaluation were compared with patients from 2000-2003 without this technique. For the 2004-2007 cohort, neuroimaging and clinical variables were compared between patients with mild Palmini type I and severe Palmini type II CD. RESULTS Compared with the 2000-2003 cohort, from 2004-2007 more CD patients were detected, most had type I CD, and fewer cases required intracranial electrodes. From 2004-2007, 85% of type I CD cases had normal non-University of California, Los Angeles (UCLA) MRI scans. UCLA MRI identified CD in 78% of patients, and 37% of type I CD cases had normal UCLA scans. EEG and neuroimaging findings were concordant in 52% of type I CD patients, compared with 89% of type II CD patients. FDG-PET scans were positive in 71% of CD cases, and type I CD patients had less hypometabolism compared with type II CD patients. Postoperative seizure freedom occurred in 82% of patients, without differences between type I and type II CD cases. CONCLUSIONS Incorporating fluorodeoxyglucose-PET/MRI coregistration into the multimodality presurgical evaluation enhanced the noninvasive identification and successful surgical treatment of patients with cortical dysplasia (CD), especially for the 33% of patients with nonconcordant findings and those with normal MRI scans from mild type I CD.
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Research Support, Non-U.S. Gov't |
16 |
201 |
5
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Horn-Ross PL, John EM, Lee M, Stewart SL, Koo J, Sakoda LC, Shiau AC, Goldstein J, Davis P, Perez-Stable EJ. Phytoestrogen consumption and breast cancer risk in a multiethnic population: the Bay Area Breast Cancer Study. Am J Epidemiol 2001; 154:434-41. [PMID: 11532785 DOI: 10.1093/aje/154.5.434] [Citation(s) in RCA: 175] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Research on the relation between phytoestrogens and breast cancer risk has been limited in scope. Most epidemiologic studies have involved Asian women and have examined the effects of traditional soy foods (e.g., tofu), soy protein, or urinary excretion of phytoestrogens. The present study extends this research by examining the effects of a spectrum of phytoestrogenic compounds on breast cancer risk in non-Asian US women. African-American, Latina, and White women aged 35-79 years, who were diagnosed with breast cancer between 1995 and 1998, were compared with women selected from the general population via random digit dialing. Interviews were conducted with 1,326 cases and 1,657 controls. Usual intake of specific phytoestrogenic compounds was assessed via a food frequency questionnaire and a newly developed nutrient database. Phytoestrogen intake was not associated with breast cancer risk (odds ratio = 1.0, 95% confidence interval: 0.80, 1.3 for the highest vs. lowest quartile). Results were similar for pre- and postmenopausal women, for women in each ethnic group, and for all seven phytoestrogenic compounds studied. Phytoestrogens appear to have little effect on breast cancer risk at the levels commonly consumed by non-Asian US women: an average intake equivalent to less than one serving of tofu per week.
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Krueger GG, Feldman SR, Camisa C, Duvic M, Elder JT, Gottlieb AB, Koo J, Krueger JG, Lebwohl M, Lowe N, Menter A, Morison WL, Prystowsky JH, Shupack JL, Taylor JR, Weinstein GD, Barton TL, Rolstad T, Day RM. Two considerations for patients with psoriasis and their clinicians: what defines mild, moderate, and severe psoriasis? What constitutes a clinically significant improvement when treating psoriasis? J Am Acad Dermatol 2000; 43:281-5. [PMID: 10906652 DOI: 10.1067/mjd.2000.106374] [Citation(s) in RCA: 163] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The definitions of psoriasis severity and clinically significant improvement in psoriasis are used to classify treatments, obtain Food and Drug Administration approval, and determine product labeling and reimbursement. The Medical Advisory Board of the National Psoriasis Foundation has addressed these issues because of their importance in the clinical trials that are conducted to gain FDA approval of indications. Narrow indications, which are without a sound rational basis, will-in this era of constant oversight by third party payers-affect physicians' ability to manage patients with psoriasis. Body surface area (BSA) is usually used to define severity for clinical trials. It is not optimal for defining psoriasis severity because there are some patients with low BSA involvement who have very severe psoriasis and some patients with high BSA involvement who have mild psoriasis. We conclude that a quality of life (QOL) standard is better than BSA measurement for identifying patients with severe psoriasis. The second issue is what defines clinically significant improvement for patients with psoriasis. Setting an arbitrarily high criterion of clinical efficacy for new psoriasis treatments will likely limit the development and approval of useful treatments. To maximize the availability of useful psoriasis treatments, it is our thesis that psoriasis treatments should be approved when they have been shown to produce a statistically significant level of improvement in well-designed clinical trials.
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163 |
7
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Horn-Ross PL, Barnes S, Lee M, Coward L, Mandel JE, Koo J, John EM, Smith M. Assessing phytoestrogen exposure in epidemiologic studies: development of a database (United States). Cancer Causes Control 2000; 11:289-98. [PMID: 10843440 DOI: 10.1023/a:1008995606699] [Citation(s) in RCA: 154] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
BACKGROUND AND OBJECTIVE Phytoestrogens (weak estrogens found in plants or derived from plant precursors by human metabolism) have been hypothesized to reduce the risk of a number of cancers. However, epidemiologic studies addressing this issue are hampered by the lack of a comprehensive phytoestrogen database for quantifying exposure. The purpose of this research was to develop such a database for use with food-frequency questionnaires in large epidemiologic studies. METHODS The database is based on consumption patterns derived from semistructured interviews with 118 African-American, Latina, and white women residing in California's San Francisco Bay Area. HPLC-mass spectrometry was used to determine the content of seven specific phytoestrogenic compounds (i.e. the isoflavones: genistein, daidzein, biochanin A, and formononetin; the coumestan: coumestrol; and the plant lignans: matairesinol and secoisolariciresinol) in each of 112 food items/groups. RESULTS Traditional soy-based foods were found to contain high levels of genistein and daidzein, as expected, as well as substantial amounts of coumestrol. A wide variety of "hidden" sources of soy (that is, soy protein isolate, soy concentrate, or soy flour added to foods) was observed. Several other foods (such as various types of sprouts and dried fruits, garbanzo beans, asparagus, garlic, and licorice) were also found to be substantial contributors of one or more of the phytoestrogens analyzed. CONCLUSIONS Databases, such as the one described here, are important in assessing the relationship between phytoestrogen exposure and cancer risk in epidemiologic studies. Agencies, such as the United States Department of Agriculture (USDA), that routinely provide data on food composition, on which epidemiologic investigations into dietary health effects are based, should consider instituting programs for the analysis of phytochemicals, including the phytoestrogens.
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154 |
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Lebwohl M, Ellis C, Gottlieb A, Koo J, Krueger G, Linden K, Shupack J, Weinstein G. Cyclosporine consensus conference: with emphasis on the treatment of psoriasis. J Am Acad Dermatol 1998; 39:464-75. [PMID: 9738783 DOI: 10.1016/s0190-9622(98)70325-1] [Citation(s) in RCA: 140] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cyclosporine has been in worldwide use for 15 years for patients who have undergone transplantation operations and is now being used to control inflammatory reactions in other organs (eg, joints, bowel, and skin). Neoral, a more consistently absorbed form of cyclosporine, has recently been approved by the Food and Drug Administration for the treatment of psoriasis. This report outlines the indications, contraindications, dosage recommendations, monitoring requirements, adverse events, drug interactions, interactions with other psoriasis treatments, and suggestions for cyclosporine's use in rotational therapy.
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Consensus Development Conference |
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140 |
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Review |
30 |
136 |
10
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Abstract
Reversible posterior leukoencephalopathy syndrome is a recently recognized disorder with characteristic radiologic findings that mainly involve the white/gray matter of the parieto-occipital lobes. This complex syndrome is associated with cyclosporine A therapy or a variety of other conditions in which blood pressure rises acutely. Twelve patients from a variety of conditions who met the diagnostic criteria for this syndrome were studied. Interestingly, three of these patients had intra-abdominal neurogenic tumors, which have rarely been reported. Initial cranial magnetic resonance imaging scans revealed fairly symmetric areas of increased T(2) signal involving both white and gray matter of parieto-occipital lobes in the majority of the patients. However, the lesions were often located outside the parieto-occipital regions. Four patients had occipital region magnetic resonance spectroscopy during the acute phase, which revealed high lactate peak and normal N-acetyl aspartate/creatine and choline peaks. With appropriate treatment, most patients recovered from this syndrome and experienced almost complete resolution of brain lesions on follow-up magnetic resonance imaging. One patient, however, continued to have small residual hemosiderin deposits on a follow-up magnetic resonance imaging with neurologic sequellae. In conclusion, a better understanding of this complex syndrome may obviate unnecessary investigations and allow management of the associated problems in prompt and appropriate ways.
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Ayers M, Sampaleanu LM, Tammam S, Koo J, Harvey H, Howell PL, Burrows LL. PilM/N/O/P proteins form an inner membrane complex that affects the stability of the Pseudomonas aeruginosa type IV pilus secretin. J Mol Biol 2009; 394:128-42. [PMID: 19857645 DOI: 10.1016/j.jmb.2009.09.034] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2009] [Revised: 09/09/2009] [Accepted: 09/12/2009] [Indexed: 01/16/2023]
Abstract
The highly conserved pilM/N/O/P/Q gene cluster is among the core set of genes required for cell surface expression of type IV pili and associated twitching motility. With the exception of the outer membrane secretin, a multimer of PilQ subunits, the specific functions of the products encoded by this gene cluster are poorly characterized. Orthologous proteins in the related bacterial type II secretion system have been shown to interact to form an inner membrane complex required for protein secretion. In this study, we provide evidence that the PilM/N/O/P proteins form a functionally equivalent type IVa pilus complex. Using Pseudomonas aeruginosa as model organism, we found that all four proteins, including the nominally cytoplasmic PilM, colocalized to the inner membrane. Stability studies via Western blot analyses revealed that loss of one component has a negative impact on the levels of other members of the putative complex. Furthermore, complementation studies revealed that the stoichiometry of the components is important for the correct formation of a stable complex in vivo. We provide evidence that an intact inner membrane complex is required for optimal formation of the outer membrane complex of the type IVa pilus system in P. aeruginosa, as PilQ stability is negatively affected in its absence. Finally, we show that, in the absence of the pilin subunit, the levels of membrane-bound components of the inner membrane complex are negatively regulated by the PilR/S two-component system, suggesting a role for PilR/S in sensing the piliation status of the cell.
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Research Support, Non-U.S. Gov't |
16 |
103 |
12
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Abstract
The armamentarium of therapies for psoriasis continues to expand with drugs such as tazarotene, calcipotriene, and acitretin approved in recent years. New forms of old treatments such as cyclosporine and anthralin have also been introduced. Frequently, inadequate attention is devoted to duration of remission. The purpose of this article is to examine the duration of remission reported with many therapies currently used for psoriasis. Studies examining duration of remission are included. Among our conclusions were the following: the definitions of remission/relapse used in various studies differ, duration of remission is influenced by the natural history of each patient's disease, among topical monotherapies anthralin and tazarotene appear to induce longer remissions than calcipotriene and corticosteroids, among systemic agents longer remissions occur with etretinate than cyclosporine or methotrexate but compared with the remission rate of phototherapeutic modalities, especially Goeckerman and PUVA therapy, the remission rates are much less.
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Review |
26 |
102 |
13
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Lebwohl M, Drake L, Menter A, Koo J, Gottlieb AB, Zanolli M, Young M, McClelland P. Consensus conference: acitretin in combination with UVB or PUVA in the treatment of psoriasis. J Am Acad Dermatol 2001; 45:544-53. [PMID: 11568745 DOI: 10.1067/mjd.2001.116347] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Although adjunctive treatment with retinoids in concert with either psoralen-ultraviolet A (PUVA) or ultraviolet B (UVB) phototherapy has been a treatment option for chronic, moderate to severe plaque psoriasis for nearly two decades, acitretin-UV therapy is an underutilized therapeutic modality. According to a recent member survey by the National Psoriasis Foundation, many psoriasis patients are frustrated with available treatment options, which they perceive as ineffective, inconvenient, and/or excessively conservative. Treatment of psoriasis with acitretin in concert with UVB or PUVA is emerging as a viable clinical strategy. Compared with either acitretin or UV light monotherapy alone, the combination regimen enhances efficacy and limits treatment frequency, duration, and cumulative doses. These effects translate into care that is more effective, better tolerated, more convenient, less costly, and, perhaps, safer during long-term treatment than phototherapy alone. Drawing from an extensive literature search and the expertise of its participants, this consensus conference advances clinical recommendations as well as "clinical pearls" for health providers who treat patients with chronic, moderate to severe plaque psoriasis and suggests avenues for future research.
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Consensus Development Conference |
24 |
100 |
14
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Horn-Ross PL, Lee M, John EM, Koo J. Sources of phytoestrogen exposure among non-Asian women in California, USA. Cancer Causes Control 2000; 11:299-302. [PMID: 10843441 DOI: 10.1023/a:1008968003575] [Citation(s) in RCA: 99] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE We recently described the development of a comprehensive database for assessing phytoestrogen exposure in epidemiologic studies. This paper describes the first application of this database and the primary sources of phytoestrogen consumption in non-Asian women. METHODS Four hundred and forty-seven randomly selected African-American, Latina, and white women, ages 50-79 years, residing in California's San Francisco Bay Area and participating as controls in an ongoing population-based case-control study of breast cancer, were included in the present analysis. Average daily consumption of each of seven phytoestrogenic compounds was determined for each woman by combining the values from the new database with food consumption reported on a food-frequency questionnaire. RESULTS Phytoestrogens in the non-Asian Bay Area diet appear to come primarily from: (1) traditional soy-based foods (e.g. tofu and soy milk); (2) "hidden" sources of soy (e.g. foods containing added soy protein isolate, soy concentrate, or soy flour, e.g. many brands of doughnuts and white bread); and (3) a variety of foods which contain only low to moderate amounts of phytoestrogens per 100 grams but which are frequently consumed (e.g. coffee and orange juice). CONCLUSIONS In the absence of a comprehensive assessment of various phytoestrogens in a wide variety of foods, epidemiologic studies could suffer from the effects of uncontrolled confounding by unmeasured sources of phytoestrogen exposure potentially leading to biased estimates of effect and misinterpretation of findings.
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99 |
15
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Koo J. Systemic sequential therapy of psoriasis: a new paradigm for improved therapeutic results. J Am Acad Dermatol 1999; 41:S25-8. [PMID: 10459144 DOI: 10.1016/s0190-9622(99)70363-4] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Sequential therapy is a treatment strategy involving the use of specific therapeutic agents in a deliberate sequence to optimize the therapeutic outcome. The rationale for this strategy in psoriasis is that it is a chronic disease requiring long-term maintenance therapy as well as quick relief of symptoms and that some therapies available for psoriasis are better suited for rapid clearance while others are more appropriate for long-term maintenance. Sequential therapy involves 3 main steps: (1) the clearing, or "quick-fix" phase; (2) the transitional phase; and (3) the maintenance phase. In the example of sequential systemic therapy described in this article, an acute exacerbation of psoriasis is brought under control promptly with the use of cyclosporine at maximum dermatologic dose (5 mg/kg daily). After 1 month, the transitional phase is initiated with the gradual introduction of acitretin as a maintenance agent. Once the maximum tolerated dose of acitretin has been established, cyclosporine is gradually tapered and acitretin is continued for long-term maintenance with phototherapy (UVB or PUVA) added for improved control if needed. The author proposes sequential therapy with cyclosporine and acitretin as a viable option for patients with psoriasis who require systemic therapy and desire an alternative to methotrexate.
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Review |
26 |
90 |
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Koo J, Arain S. Traditional Chinese medicine for the treatment of dermatologic disorders. ARCHIVES OF DERMATOLOGY 1998; 134:1388-93. [PMID: 9828872 DOI: 10.1001/archderm.134.11.1388] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Traditional Chinese medicine (TCM) is an alternative method of therapy that can be administered in oral, topical, or injectable forms. It emphasizes the importance of using many herbs that are combined in different formulations for each individual patient. Among some segments of the patient population, it has become increasingly popular as a mode for treating dermatologic diseases. As a result, it is now worthwhile for dermatologists throughout the West to gain some familiarity with this method. Yet, dermatologists are largely unfamiliar with TCM and may possess some misconceptions. We attempt to give a general overview of TCM through the discussion of different clinical studies involving various TCMs. Some proposed mechanisms of action of TCM are also presented. A discussion of adverse effects, including hepatotoxic effects and the need for close monitoring is discussed. A warning regarding the possible contamination of TCMs is also included. Since it is not possible to discuss the application of TCM for every skin disorder, psoriasis and atopic dermatitis are used as the prototype in illustrating the use of TCM. In the future, perhaps a better understanding of TCM will be gained through more systematic analysis and controlled studies with a placebo arm. It is our hope that this article will provide an overview of the efficacy, mechanism of action, as well as adverse effects of TCM.
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Review |
27 |
87 |
17
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D'Andrea AD, Yoshimura A, Youssoufian H, Zon LI, Koo JW, Lodish HF. The cytoplasmic region of the erythropoietin receptor contains nonoverlapping positive and negative growth-regulatory domains. Mol Cell Biol 1991; 11:1980-7. [PMID: 1848667 PMCID: PMC359883 DOI: 10.1128/mcb.11.4.1980-1987.1991] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The erythropoietin (EPO) receptor (EPO-R), a member of a large cytokine receptor superfamily, has a 236-amino-acid cytoplasmic region which contains no obvious tyrosine kinase or other catalytic domain. In order to delineate the linear functional domains of the cytoplasmic tail, we generated truncated mutant cDNAs which were transfected into a murine interleukin-3-dependent cell line, Ba/F3, and the EPO-dependent growth characteristics of the stable transfectants were assayed. We identified two unique domains of the cytoplasmic tail. A membrane-proximal positive signal transduction domain of less than or equal to 103 amino acids, in a region highly similar to the interleukin-2 receptor beta chain, was sufficient for EPO-mediated signal transduction. A carboxy-terminal negative-control domain, a serine-rich region of approximately 40 amino acids, increased the EPO requirement for the Ba/F3 transfectants without altering EPO-R cell surface expression, affinity for EPO, receptor oligosaccharide processing, or receptor endocytosis. Truncation of this negative-control domain allowed the Ba/F3 transfectants to grow maximally in only 1 pM EPO, 1/10 the concentration required for growth of cells expressing the wild-type EPO-R. All truncated EPO-R mutants which retained the transmembrane region of the EPO-R polypeptide bound to the gp55 envelope protein of Friend spleen focus-forming virus. Only the functional EPO-R mutants were activated by the gp55, however, suggesting that gp55- and EPO-mediated signaling occur via a similar mechanism.
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research-article |
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Abstract
Delusions of parasitosis is a rare psychiatric disorder in which the patient has a fixed, false belief that he or she is infested by parasites. Even though it is a psychiatric disorder, these patients usually present to a dermatologist because they are convinced that they have a dermatological problem. Patients with delusions of parasitosis generally reject psychiatric referral. The diagnosis of delusions of parasitosis can often be made on the basis of the history alone, but it is important to make sure that the patient does not have a organic skin disorder, and the delusion is not secondary to another mental or physical illness. The current treatment of choice is the antipsychotic medication pimozide. The principal difficulty in management is convincing patients to take the drug. This results from the obvious discrepancy between the patients' belief system and the clinician's understanding of the situation. The most common adverse effects of pimozide are extrapyramidal symptoms such as stiffness and, less frequently, a special inner sense of restlessness called akathisia. Effective treatment of such extrapyramidal reactions includes benztropine 1 to 2 mg up to 4 times daily as needed, or diphenhydramine 25 mg 3 times daily as needed. Pimozide can have cardiotoxic effects at high dosages. Traditionally, it has been recommended to check pretreatment and post-treatment electrocardiograms even for patients who have no history or cardiac conduction abnormalities or arrhythmia. However, a more recent publication questions the need for this if the patient takes < 10 mg/day, is not elderly, and has no history of cardiac arrhythmia. Effective dosages of pimozide for delusions of parasitosis have ranged from 1 to 10 mg/day. The lowest effective dosage of pimozide should be used for the shortest possible duration to minimize the risk of tardive dyskinesia developing in these patients. Significant improvements in quality of life have been achieved with successful treatment with pimozide. Atypical antipsychotics such as risperidone with a much safer adverse effect profile may prove to be effective for the treatment of delusions of parasitosis in the future.
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73 |
19
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van den Brink A, Vermijs G, Solignac A, Koo J, Kohlhepp JT, Swagten HJM, Koopmans B. Field-free magnetization reversal by spin-Hall effect and exchange bias. Nat Commun 2016; 7:10854. [PMID: 26940861 PMCID: PMC5411711 DOI: 10.1038/ncomms10854] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Accepted: 01/27/2016] [Indexed: 11/09/2022] Open
Abstract
As the first magnetic random access memories are finding their way onto the market, an important issue remains to be solved: the current density required to write magnetic bits becomes prohibitively high as bit dimensions are reduced. Recently, spin–orbit torques and the spin-Hall effect in particular have attracted significant interest, as they enable magnetization reversal without high current densities running through the tunnel barrier. For perpendicularly magnetized layers, however, the technological implementation of the spin-Hall effect is hampered by the necessity of an in-plane magnetic field for deterministic switching. Here we interface a thin ferromagnetic layer with an anti-ferromagnetic material. An in-plane exchange bias is created and shown to enable field-free S HE-driven magnetization reversal of a perpendicularly magnetized Pt/Co/IrMn structure. Aside from the potential technological implications, our experiment provides additional insight into the local spin structure at the ferromagnetic/anti-ferromagnetic interface. Future information storage technology may exploit electrical currents to write the states of ferromagnetic nanoelements via spin torque effects. Here, the authors demonstrate such behaviour promoted by exchange bias from an interfaced antiferromagnet, which may help overcome practical device limitations.
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Research Support, Non-U.S. Gov't |
9 |
70 |
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Sampaleanu LM, Bonanno JB, Ayers M, Koo J, Tammam S, Burley SK, Almo SC, Burrows LL, Howell PL. Periplasmic domains of Pseudomonas aeruginosa PilN and PilO form a stable heterodimeric complex. J Mol Biol 2009; 394:143-59. [PMID: 19857646 DOI: 10.1016/j.jmb.2009.09.037] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2009] [Revised: 09/09/2009] [Accepted: 09/17/2009] [Indexed: 11/18/2022]
Abstract
Type IV pili (T4P) are bacterial virulence factors responsible for attachment to surfaces and for twitching motility, a motion that involves a succession of pilus extension and retraction cycles. In the opportunistic pathogen Pseudomonas aeruginosa, the PilM/N/O/P proteins are essential for T4P biogenesis, and genetic and biochemical analyses strongly suggest that they form an inner-membrane complex. Here, we show through co-expression and biochemical analysis that the periplasmic domains of PilN and PilO interact to form a heterodimer. The structure of residues 69-201 of the periplasmic domain of PilO was determined to 2.2 A resolution and reveals the presence of a homodimer in the asymmetric unit. Each monomer consists of two N-terminal coiled coils and a C-terminal ferredoxin-like domain. This structure was used to generate homology models of PilN and the PilN/O heterodimer. Our structural analysis suggests that in vivo PilN/O heterodimerization would require changes in the orientation of the first N-terminal coiled coil, which leads to two alternative models for the role of the transmembrane domains in the PilN/O interaction. Analysis of PilN/O orthologues in the type II secretion system EpsL/M revealed significant similarities in their secondary structures and the tertiary structures of PilO and EpsM, although the way these proteins interact to form inner-membrane complexes appears to be different in T4P and type II secretion. Our analysis suggests that PilN interacts directly, via its N-terminal tail, with the cytoplasmic protein PilM. This work shows a direct interaction between the periplasmic domains of PilN and PilO, with PilO playing a key role in the proper folding of PilN. Our results suggest that PilN/O heterodimers form the foundation of the inner-membrane PilM/N/O/P complex, which is critical for the assembly of a functional T4P complex.
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Research Support, U.S. Gov't, Non-P.H.S. |
16 |
69 |
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Lam SK, Lee NW, Koo J, Hui WM, Fok KH, Ng M. Randomised crossover trial of tripotassium dicitrato bismuthate versus high dose cimetidine for duodenal ulcers resistant to standard dose of cimetidine. Gut 1984; 25:703-6. [PMID: 6376292 PMCID: PMC1432590 DOI: 10.1136/gut.25.7.703] [Citation(s) in RCA: 68] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Of 212 patients with duodenal ulcer treated with four weeks of one gram daily cimetidine, 25 had ulcers which underwent no reduction in size despite treatment. The effects of tripotassium dicitrato bismuthate (TDB) tablet four times a day or cimetidine 1.6 g daily on the healing of these cimetidine resistant ulcers were compared in a randomised crossover trial. Ten of 12 patients on tripotassium dicitrato bismuthate and five of 13 patients on high dose cimetidine had complete healing (p less than 0.02). On crossing over, seven of the eight ulcers not healed by high dose cimetidine completely healed with TDB in another four weeks, and one of the two ulcers not healed by TDB healed with high dose cimetidine. Overall, TDB healed 85% of cimetidine resistant ulcers, whereas high dose cimetidine healed 40% (p less than 0.006). Tripotassium dicitrato bismuthate is recommended for cimetidine resistant duodenal ulcers.
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research-article |
41 |
68 |
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Koo J. A randomized, double-blind study comparing the efficacy, safety and optimal dose of two formulations of cyclosporin, Neoral and Sandimmun, in patients with severe psoriasis. OLP302 Study Group. Br J Dermatol 1998; 139:88-95. [PMID: 9764154 DOI: 10.1046/j.1365-2133.1998.02319.x] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
This study compared the efficacy, safety and optimal dose of two formulations of cyclosporin, Sandimmun and Neoral, in patients with severe, chronic plaque-type psoriasis. Patients were randomized on a 1:1 basis to 24 weeks of treatment with Neoral (n = 152) or Sandimmun (n = 157). The starting dose of each formulation was 2.5 mg/kg per day. Dose increases to maintain efficacy were allowed after 4 weeks. In patients who achieved remission, the dose was down-titrated at 4-week intervals from week 16. The maximum permitted dose for each formulation was 5.0 mg/kg per day. Neoral produced a more rapid response than Sandimmun: remission rates were higher for Neoral during the first 8 weeks of treatment. The number of dose reductions for safety was similar in both treatment groups, but there were more dose increases to maintain efficacy in the Sandimmun group (198) than the Neoral group (146). The number of patients with dose reductions after week 16 was higher for Neoral (n = 83) than for Sandimmun (n = 73). The frequency and nature of adverse events were similar for both treatment groups. The mean dose required to control the disease was approximately 10% lower with Neoral and fewer dose changes were needed. The increased bioavailability and reduced pharmacokinetic variability of cyclosporin provided by the Neoral formulation may facilitate short-course, intermittent therapy.
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Clinical Trial |
27 |
65 |
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Shupack J, Abel E, Bauer E, Brown M, Drake L, Freinkel R, Guzzo C, Koo J, Levine N, Lowe N, McDonald C, Margolis D, Stiller M, Wintroub B, Bainbridge C, Evans S, Hilss S, Mietlowski W, Winslow C, Birnbaum JE. Cyclosporine as maintenance therapy in patients with severe psoriasis. J Am Acad Dermatol 1997; 36:423-32. [PMID: 9091474 DOI: 10.1016/s0190-9622(97)80219-8] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Low-dose cyclosporine therapy for severe plaque psoriasis is effective. Most side effects can be controlled by patient monitoring, with appropriate dose adjustment or pharmacologic intervention, or both, if indicated. Prevention or reversibility of laboratory and chemical abnormalities may be achieved by discontinuation of therapy after the induction of clearing. However, relapse occurs rapidly on discontinuation. Maintenance therapy with cyclosporine after induction has not been fully evaluated. OBJECTIVE Our purpose was to compare a regimen of 3.0 mg/kg per day of oral cyclosporine with placebo in maintaining remission or improvement in patients with psoriasis. METHODS After a 16-week unblinded induction phase in which 181 patients received cyclosporine, 5.0 mg/kg per day (an increase up to 6.0 mg/kg per day and a decrease to 3.0 mg/kg per day were allowed, if required, to achieve efficacy or tolerability, respectively), those patients showing a 70% decrease or more in involved body surface area (BSA) entered the 24-week maintenance phase and were randomly assigned to either placebo, cyclosporine, 1.5 mg/kg per day, or cyclosporine, 3.0 mg/kg per day. Patients were considered to have had a relapse when BSA returned to 50% or more of the prestudy baseline value. Clinical efficacy, adverse effects, and laboratory values were monitored regularly throughout both study phases. RESULTS During induction, cyclosporine at approximately 5.0 mg/kg per day produced a reduction in BSA of 70% or more in 86% of the patients. During maintenance, the median time to relapse was 6 weeks in both the placebo and cyclosporine 1.5 mg/kg per day groups, but was longer than the 24-week maintenance period in the 3.0 mg/kg per day group (p < 0.001 vs placebo). By the end of the maintenance period, 42% of the patients in the 3.0 mg/kg per day cyclosporine group had a relapse compared with 84% in the placebo group. Changes in laboratory values associated with the higher induction dosage generally exhibited partial or complete return toward mean prestudy baseline values during the maintenance phase, with the greatest degree of normalization in the placebo group. CONCLUSION Cyclosporine, 3.0 mg/kg per day, adequately and safely maintained 58% of patients with psoriasis for a 6-month period after clearing of their psoriasis with doses of approximately 5.0 mg/kg per day.
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Clinical Trial |
28 |
62 |
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Boey J, Lee NW, Koo J, Lam PH, Wong J, Ong GB. Immediate definitive surgery for perforated duodenal ulcers: a prospective controlled trial. Ann Surg 1982; 196:338-44. [PMID: 7114938 PMCID: PMC1352612 DOI: 10.1097/00000658-198209000-00013] [Citation(s) in RCA: 60] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
A prospective, randomized, double-blind trial was conducted in 101 patients to evaluate the safety and benefits of immediate definitive surgery for perforated duodenal ulcers. These patients, who were judged by predefined criteria to be medically fit and to have perforations in chronic ulcers, were randomized to undergo simple closure (35 patients), truncal vagotomy and drainage (VD) (32 patients), or proximal gastric vagotomy with closure (PGV) (34 patients). Patients were followed with endoscopic assessment for up to 39 months. There was no mortality and only a few minor postoperative complications. At 39 months follow-up, the cumulative rates of recurrence were 63.3%, 11.8% and 3.8% after closure, VD, and PGV, respectively (p less than 0.001). With the exception of the one recurrence after PGV, all relapses were symptomatic, and eight of these 18 required reoperation. Relapse rates and Visick scores between VD and PGV were significantly different. Both safe as well as effective, immediate, nonresective, definitive operation is indicated for good-risk patients who have perforations in chronic duodenal ulcers.
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research-article |
43 |
60 |
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Jamali F, Mehvar R, Russell AS, Sattari S, Yakimets WW, Koo J. Human pharmacokinetics of ibuprofen enantiomers following different doses and formulations: intestinal chiral inversion. J Pharm Sci 1992; 81:221-5. [PMID: 1640357 DOI: 10.1002/jps.2600810306] [Citation(s) in RCA: 60] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The influences of absorption rate and dosage size on the pharmacokinetics of ibuprofen (IB) enantiomers were studied in six healthy subjects. Rapidly absorbed solutions (50, 100, 200, 400, 600, and 1200 mg) and regular 600-mg tablets of racemic IB were given orally, and plasma concentration-time courses of the enantiomers were followed. Solutions were absorbed faster (tmax less than 0.25 h) than the tablet (tmax = 2.17 +/- 1.17 h). While the S:R AUC ratios were unaffected by increasing the dose, they were significantly greater after the tablet (1.35 +/- 0.14) as compared with the solutions (1.15 +/- 0.16 to 1.24 +/- 0.26). This indicates a greater extent of chiral inversion for the tablet, perhaps due to a longer residence time in the gut, thereby allowing more presystemic inversion. To test this hypothesis, R-IB was incubated at 37 degrees C in the presence of excised segments of human ileum and colon obtained from three patients. Chiral inversion was evident in all segments. After 3 h, the extent of inversion ranged from 20.0 to 33.0%. In addition, incubation resulted in the formation of up to 23.3 and 13.0% of acylglucuronides of S- and R-IB, respectively. In all subjects, the AUC-dose relationships were nonlinear, indicating a gradual increase in the clearance of both enantiomers due, perhaps, to a parallel saturation of plasma protein binding sites. In humans, the chiral inversion of IB is not influenced by the dosage size but is enhanced by prolongation of the residence time in the intestine.
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Comparative Study |
33 |
60 |