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J Y Koo

Publications and source records attributed to J Y Koo.

36 records · Page 2Linked to original sources
PubMed1994

Bombesin inhibits growth of pancreatic ductal adenocarcinoma (H2T) in nude mice.

Bombesin (BBS), a tetradecapeptide, stimulates growth of various types of cells, including fibroblasts and human small cell lung cancer, and has been termed the universal "on-switch" due to its ability to stimulate the release of numerous hormones. In addition, BBS receptors have been identified in normal and neoplastic pancreatic tissue. A pancreatic ductal adenocarcinoma cell line (H2T), established in our laboratory, possesses specific binding sites for BBS. The purpose of this study was to examine the effect of BBS on the growth of H2T tumors transplanted into athymic nude mice. H2T cells (5 x 10(6) cells/mouse) were injected s.c. into the interscapular region of the nude mice and then the mice were randomized into two groups (n = 10/group). Mice received either 0.1 ml of saline with 0.1% bovine serum albumin (BSA) (control) or 0.1 ml BBS (5 micrograms/kg) intraperitoneally, three times/day. Tumor area was measured twice weekly until the mice were killed (day 32), when tumor and normal pancreas were removed, weighted, and assayed for DNA and protein content. Administration of BBS significantly inhibited H2T tumor area, weight, and DNA and protein content. Conversely, growth of normal pancreas, removed as an in vivo bioassay so as to ensure the efficacy of BBS, was stimulated. We conclude that BBS is a growth inhibitory factor for H2T tumors and that different mechanisms may be responsible for the differential growth effects elicited by normal and neoplastic pancreas in response to BBS.

Animals↗
PubMed1994

Alopecia areata and increased prevalence of psychiatric disorders.

BACKGROUND: The relationship between psychiatric disorders and alopecia areata has not been well studied. Although previous reports have been unable to correlate psychiatric illness with hair loss, a recent study determined that 74% of patients with alopecia areata (AA) under evaluation had one or more lifetime psychiatric diagnoses. METHODS: Two hundred and ninety-four community-based patients with alopecia areata responded to a detailed questionnaire distributed by Help Alopecia International Research, Inc. The prevalence of psychiatric disorders was determined using diagnostic criteria from the Diagnostic and Statistical Manual of Mental Disorders (DSM-IIIR). RESULTS: Major depression, generalized anxiety disorder, social phobia, and paranoid disorder were all present in patients with alopecia areata at rates significantly higher than in the general population. CONCLUSIONS: Alopecia areata patients are at a higher risk of developing psychiatric comorbidity during their clinical course.

Alopecia Areata↗
PubMed1994

Angiodysplastic syndrome with capillary and venous malformation associated with soft tissue hypotrophy.

Angiodysplastic syndromes include a vascular malformation which may often be associated with secondary changes such as further vascular abnormalities, soft tissue and bone hypertrophy. One of the best known is the syndrome triad originally described by Klippel and Trenaunay, which includes a unilateral capillary malformation, ectatic veins and osseous and soft tissue hypertrophy. A female patient is reported who had an extensive capillary malformation, discrete ectatic veins overlying an extensive venous malformation and soft tissue hypotrophy without bone involvement. Our patient and cases from the literature illustrate the occurrence of 'atypical', hypotrophic variants of angiodysplastic syndromes. Discrete superficial angiodysplasias may overlie deep, extensive malformations, and identification of such cases is important with regard to management and prognosis. The current classification of angiodysplasias is based on the primary vascular malformation. The use of eponyms should be avoided, because they do not contribute to the diagnosis and management of such cases.

Adolescent↗
PubMed1993

Plasma levels of 8-methoxypsoralen after topical paint PUVA.

BACKGROUND: Topical PUVA therapy has become a useful alternative for patients who cannot tolerate the systemic side effects of nausea and headache or are concerned about the ophthalmologic risk associated with oral PUVA therapy. However, there is no study to date on the systemic absorption of psoralen after the localized application of topical paint PUVA. OBJECTIVE: This study was designed to assess the plasma level of 8-methoxypsoralen (8-MOP) after paint PUVA therapy for patients with palmoplantar psoriasis or eczema. METHODS: Reverse-phase high-pressure liquid chromatography was used to determine 8-MOP plasma levels in eight patients with palmoplantar psoriasis and two with eczema. Three patients receiving oral PUVA therapy served as the control group. RESULTS: Plasma levels of 8-MOP taken 1, 6, and 24 hours after topical PUVA treatments of patients with palmoplantar psoriasis were undetectable. One patient with hand eczema consistently had detectable 8-MOP levels 1 hour after topical PUVA treatments. CONCLUSION: This report indicates that there is minimal, if any, systemic absorption of 8-MOP after topical PUVA treatment of patients with palmoplantar psoriasis.

Administration, Topical↗
PubMed1993

Bombesin stimulates growth of colon cancer in mice and decreases their survival.

Bombesin (BBS) stimulates cellular proliferation of both normal and transformed cells. The mouse colon cancer cells (MC-26) possess specific binding sites for BBS. The purpose of this study, therefore, was to examine the effect of chronic administration of BBS on in vivo growth of MC-26 tumours in Balb/c mice and on survival of tumour-bearing mice. Three groups of mice (n = 10 each) inoculated with MC-26 cells received either saline containing 0.1% bovine serum albumin (BSA), or BBS (5 micrograms kg-1 or 20 micrograms kg-1) dissolved with 0.1% BSA saline by intraperitoneal route three times a day for 15 days. BBS increased weight, DNA and RNA contents of MC-26 tumours. To examine the effect of BBS on survival rates of mice with MC-26 tumours, three groups of mice (n = 20 each) were treated for 31 days, as above. One group of mice inoculated with MC-26 cells received 0.1% BSA saline; the other group of MC-26-inoculated mice and the control group without tumour received BBS (5 micrograms kg-1) dissolved with 0.1% BSA saline. BBS significantly decreased the survival rate of mice bearing MC-26 tumours (median survival; saline group: 42.5 days, BBS group: 32.0 days, P = 0.037). None of the mice in the control group died during the experiment. BBS may stimulate in vivo growth of MC-26 cells through specific receptors.

Animals↗
PubMed1993

Psychotropic agents in dermatology.

In this article, relatively detailed explanation of the use of selected psychopharmacologic agents is given along with their dermatologic and psychodermatologic indications. For a more complete description of the use of these medications, the reader is advised to consult standard textbooks on psychopharmacology and the Physician's Desk Reference. It should be emphasized that psychiatric consultation should be obtained whenever feasible. Yet for a significant proportion of psychodermatologic patients who refuse psychiatric input, the judicious use of these medications may provide much-needed assistance in their recovery from psychodermatologic disorders.

Anxiety Disorders↗
PubMed1992

Psychodermatology. Practical guidelines on pharmacotherapy.

BACKGROUND: The importance of emotional factors in dermatologic disorders has been recognized for several decades. However, there have been few reports on the management of psychodermatologic disorders. Meanwhile, there has been tremendous progress in the pharmacologic treatment of these conditions. This article describes major categories of psychodermatologic disorders and provides practical management guidelines, emphasizing the use of selected psychopharmacologic agents. OBSERVATIONS: Psychodermatologic conditions can be divided into three broad subgroups: psychophysiologic disorders in which the severity of primary cutaneous disease is influenced by the patients' emotions; primary psychiatric disorders in which the skin conditions are self-induced and reflect underlying psychopathologic conditions; and secondary psychiatric disorders in which the patients experience psychologic problems as a result of disfigurement associated with the skin conditions. There are many ways to manage these psychodermatologic conditions, including psychotherapy, behavioral therapy, and psychopharmacotherapy. To determine which pharmacologic agent is most appropriate, the nature of the underlying psychopathologic condition such as anxiety, depression, psychosis, and obsession/compulsion should be identified. Furthermore, there are nonpsychiatric disorders encountered by dermatologists in which psychopharmacologic agents may be more efficacious than conventional therapeutics. CONCLUSION: We conclude that psychopharmacologic agents provide a useful option to the management of psychodermatologic disorders.

Depressive Disorder↗
PubMed1992

The development of B-cell lymphoma in a patient with psoriasis treated with cyclosporine.

A 67-year-old Nicaraguan man with a history of chronic, severe, recalcitrant psoriasis participated in a multicenter study investigating oral cyclosporine in the treatment of psoriasis. He received cyclosporine for approximately 8 months at doses of 5 mg/kg/day or less. Treatment with cyclosporine was eventually discontinued because of progressive nephrotoxicity. Approximately 7 months after the discontinuation of cyclosporine, the patient developed a mass in the left maxillary sinus extending to the orbit, the palate, and the infratemporal fossa. Pathologic and histochemical analysis of the mass revealed a B-cell lymphoma. The development of a benign lymphocytic infiltrate has been reported in a patient who received cyclosporine therapy for psoriasis; however, to the best of our knowledge, this is the first case in the United States of lymphoma developing in a patient who was treated with cyclosporine for a condition other than organ transplantation.

Administration, Oral↗
PubMed1992

Amiloride inhibits the growth of human colon cancer cells in vitro.

Cytoplasmic alkalinization induced by activation of the Na+/H+ antiport plays an essential role in the initiation of cell proliferation. In the present study we examined the effects of amiloride, a specific and reversible inhibitor of Na+/H+ antiporter, on the growth of human colon cancer cells (HT-29). Amiloride (50-800 microM) inhibited the growth of HT-29 cells in a dose-dependent fashion. Forty-three percent inhibition of growth was found at an amiloride concentration of 400 microM after 4 days of treatment. The inhibitory effect of amiloride on growth of HT-29 cells was reversible since removal of amiloride by a media change after 48 h treatment lead to rapid regrowth to control levels. The reversibility of growth inhibition suggests that amiloride is not a non-specific cytotoxin for HT-29 cells. We examined the possible mechanisms for the inhibitory effects of amiloride. Amiloride (400 microM) completely abolished serum-stimulated ODC activity and inhibited difluoromethylornithine (DMFO)-stimulated putrescine uptake by 56%. We conclude that amiloride inhibits the in vitro growth of human colon cancer cells; since ODC-activity and polyamine transport were both inhibited, the inhibitory effects may be mediated in part by polyamine-dependent processes. Amiloride may be a useful agent in the treatment of colon cancer.

Adenocarcinoma↗
PubMed1992

Profile of alopecia areata: a questionnaire analysis of patient and family.

Eight hundred patients with alopecia areata (AA) responded to a detailed questionnaire that was compiled, distributed, and analyzed by Help Alopecia International Research, Inc. (HAIR). Among those responding, 28% were men and 72% were women. Fifty percent had localized alopecia, 30% had alopecia totalis, and 20% had alopecia universalis. Forty-eight percent developed their initial onset before the age of 20. A very strong family history of 42% was found. There were 333 additional family members with AA. Many patients and relatives had concurrent atopic diseases (seasonal rhinitis, bronchial asthma, and atopic dermatitis). Associated autoimmune diseases including vitiligo, thyroid disease, and collagen vascular disease in patients and relatives appeared consistent with previous reports. Insulin dependent diabetes mellitus (IDDM) was not increased in patients but greatly increased in relatives. Additional analysis suggests a genetic association between the two diseases where expression of AA may prevent the development of IDDM.

Alopecia Areata↗
PubMed1992

The use of psychotropic medications in clinical dermatology.

In this article, the use of selected psychopharmacologic medications was explained in detail. If a patient who is obviously suffering from a psychiatric component of his or her disorder that can be responsive to psychopharmacotherapy refuses to accept a referral to a psychiatrist or other mental health professional, the dermatologist must decide whether to use these medications. If he or she decides to use these medications, it should always be remembered that the choice of psychopharmacologic treatment depends on the nature of the underlying psychopathology-anxiety, psychosis, depression, or compulsion-rather than on the dermatologic label such as neurotic excoriations. It is the hope of the author that more patients who fall into this interface between psychiatry and dermatology will be helped if dermatologists become more familiar with the availability and use of these medications.

Anti-Anxiety Agents↗
PubMed1991

Obsessive-compulsive disorders in the pediatric dermatology practice.

Childhood and adolescent obsessive-compulsive disorders are sometimes seen in dermatology practice. When present, OCD is most frequently manifested in younger patients as trichotillomania, onychotillomania, onychophagia, and acne excoriée. In addition to these disorders, obsessive hand washing, AIDS phobia, and other psychosomatic dermatoses characterized by obsessive-compulsive tendencies are seen in all age groups. It is important to define the nature of any underlying psychiatric disorder before beginning drug treatment of these patients. With the availability of new medications, most notably, clomipramine and fluoxetine, there is reason for optimism regarding the treatment of OCD. Whenever feasible, the dermatologist should not hesitate to involve a psychiatrist to help with diagnosis and treatment when the diagnosis of OCD is being considered.

Child↗
PubMed1991

Psychologic aspects of acne.

Psychologic factors may play a significant role in acne in at least three ways. First, as many patients readily report, emotional stress can exacerbate acne. Second, it is common for patients to develop psychiatric problems as a consequence of the conditions, such as those related to low self-esteem, social phobias, or depression. Finally, primary psychiatric illnesses such as obsessive-compulsive disorder and psychosis may be based on a complaint that is focused on acne. In this review we hope to facilitate an understanding of how emotional factors and acne connect, and aid the dermatologist in identifying the possible presence of psychiatric problems stemming from or contributing to the disorder.

Acne Vulgaris↗
PubMed1989

Relationship between T-lymphocyte subsets and suppressor cell activity in patients with chronic active hepatitis B.

Thirty-nine patients with chronic HBV infection and 38 normal persons were investigated by simultaneous assay of T suppressor cell function and enumeration of T-lymphocyte subsets by monoclonal antibodies. In patients with chronic active hepatitis B (CAH-B), T suppressor cell activity (17.8 +/- 8.8%) was significantly lower than in healthy HBsAg carriers (35.4 +/- 12.3%) and normal control persons (38.3 +/- 16.3%). The proportions of T-lymphocyte subsets in patients with CAH-B were not different from those of healthy HBsAg carriers and control persons. No correlation was observed in between percentage suppression and proportions of T-lymphocyte subsets. These findings suggest that in the absence of a simultaneous assay of function, enumeration of T-lymphocyte subsets by using monoclonal antibodies is an inadequate assessment of immune regulation.

Adult↗
PubMed1986

Coma following ECT and intravenous droperidol: case report.

A 60-year-old man with psychotic depression became comatose following the administration of intravenous droperidol given for post-ECT delirious agitation. The differential diagnosis, which included neuroleptic malignant syndrome and the possibility that droperidol may have uniquely detrimental effects in the context of post-ECT delirium, are discussed. In light of recent publications advocating droperidol as the pharmacologic treatment of choice for severe agitation, this case illustrates a need for greater caution in its use for the treatment of post-ECT delirium.

Coma↗
PubMedDate not supplied

HIV and psoriasis.

Explore the source record for details and available documents.

AIDS-Related Opportunistic Infections↗