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Lai JY, de Grauw WJ, de Boer WA. Helicobacter treatment with quadruple therapy in primary health care for patients with a history of ulcer disease. Fam Pract 1999; 16:483-8. [PMID: 10533944 DOI: 10.1093/fampra/16.5.483] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Few patients with a history of peptic ulcer are treated by their GP for H. pylori infection, even though theoretical evidence supports such an approach. OBJECTIVES We aimed to determine the validity of this recommendation and to test the feasibility of quadruple therapy in primary health care. METHODS In this prospective, non-randomized intervention study, 51 unselected patients with a history of proven ulcer disease received a 7-day quadruple therapy (lansoprazole, colloidal bismuth subcitrate, tetracycline and metronidazole) from their GP. Main outcome measures were: (i) endoscopically confirmed cure of the infection; (ii) results of serology at entry and at 6 months follow-up; (iii) quality of life at entry, at 6 weeks and at 6 months follow-up; (iv) gastric symptoms at entry, at 6 weeks and at 6 months follow-up; and (v) medication at entry and at 6 months follow-up. RESULTS Quadruple therapy was well tolerated and there were no drop-outs with this regimen. Intention to treat cure rate was 48/51 (94%, 95% CI 87-100%), per protocol cure rate was 48/49 (98%, 95% CI 94-100%). 45/50 (90%) had positive serology at entry. IgG antibody titres decreased > 40% in 95.2% of patients. Quality of life improved significantly after treatment, gastric symptoms decreased and medication use decreased. CONCLUSIONS GPs should be encouraged to identify patients with a history of ulcer disease and chronic use of acid suppressants and offer them treatment for H. pylori infection. This approach will cure the infection in almost all patients, it will improve the quality of life and decrease costs. Quadruple therapy does not lose efficacy when employed in primary care. Pre-treatment serological testing is potentially useful for narrowing down the treatment group to those with actual infection, and serology is promising as an easy and cheap follow-up instrument in primary health care.
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Hsieh WS, Yang PH, Chao HC, Lai JY. Neonatal necrotizing fasciitis: a report of three cases and review of the literature. Pediatrics 1999; 103:e53. [PMID: 10103345 DOI: 10.1542/peds.103.4.e53] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVE Necrotizing fasciitis (NF) is a predominantly adult disorder, with bacterial infection of the soft tissue. In children, it is relatively rare and has a fulminant course with a high mortality rate. In the neonate, most cases of NF are attributable to secondary infection of omphalitis, balanitis, mammitis, postoperative complications, and fetal monitoring. The objective of this communication is to report 3 cases of neonatal NF and provide a literature review of this disorder. RESULTS This review yielded 66 cases of neonatal NF. Only 3 cases were premature. There was no sex predilection and the condition rarely recurred. Several underlying conditions were identified that might have contributed to the development of neonatal NF. These included omphalitis in 47, mammitis in 5, balanitis in 4, fetal scalp monitoring in 2, necrotizing enterocolitis, immunodeficiency, bullous impetigo, and maternal mastitis in 1 patient each. The most common site of the initial involvement was the abdominal wall (n = 53), followed by the thorax (n = 7), back (n = 2), scalp (n = 2), and extremity (n = 2). The initial skin presentation ranged from minimal rash to erythema, edema, induration or cellulitis. The lesions subsequently spread rapidly. The overlying skin might later develop a violaceous discoloration, peau d'orange appearance, bullae, or necrosis. Crepitus was uncommon. Fever and tachycardia were frequent but not uniformly present. The leukocyte count of the peripheral blood was usually elevated with a shift to the left. Thrombocytopenia was noted in half of the cases. Hypocalcemia was rarely reported. Of the 53 wound cultures available for bacteriologic evaluation, 39 were polymicrobial, 13 were monomicrobial, and 1 was sterile. Blood culture was positive in only 20 cases (50%). Treatment modalities included the use of antibiotics, supportive care, surgical debridement, and drainage of the affected fascial planes. Two of the 6 cases who received hyperbaric oxygen therapy died. The overall mortality rate was 59% (39/66). In 12 cases, skin grafting was required because of poor granulation formation or large postoperative skin defects among the survivors. CONCLUSION Neonatal NF is an uncommon but often fatal bacterial infection of the skin, subcutaneous fat, superficial fascia, and deep fascia. It is characterized by marked tissue edema, rapid spread of inflammation, and signs of systemic toxicity. The wound cultures are predominantly polymicrobial and the location of initial involvement depends on the underlying etiologic factor. High index of suspicion, prompt aggressive surgery, appropriate antibiotics, and supportive care are the mainstays of management in the newborn infant with NF.
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Chao HC, Huang YC, Kong MS, Hsieh WS, Lin TY, Lai JY. Prompt recognition of necrotizing fasciitis in a newborn. ACTA PAEDIATRICA TAIWANICA = TAIWAN ER KE YI XUE HUI ZA ZHI 1999; 40:43-5. [PMID: 10910586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
We report a 13-day-old female neonate with necrotizing fasciitis, who presented with fever and erythema on her back. Rapidly progressive extension of the erythema to the abdominal wall occurred within 12 hours. Sonography for the lesion showed extensive fascial thickening with fluid accumulation. An abscess was also demonstrated. Necrotizing fasciitis was highly suspected. Under sonographic guidance, pus was aspirated from the abscess. A smear for the aspirated pus revealed a large number of neutrophils and abundant gram-positive cocci. Immediate surgical debridement was done. Cultures from the pus and blood revealed Staphylococcus aureus. The patient was free of symptoms after surgical debridement and aggressive antibiotic therapy. She had skin grafting to reconstruct the debrided wound on the 20th hospital day and was discharged shortly after the debridement of wound.
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Lau KK, Lai ST, Lai JY, Yan WW, So TMK, Wong TY. Acute encephalitis complicating rubella. Hong Kong Med J 1998; 4:325-328. [PMID: 11830692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
During an epidemic of rubella in Hong Kong between October 1996 and June 1997, four male patients presented with rubella complicated by encephalitis, the symptoms of which started 1 to 5 days after the appearance of the rash characteristic of rubella. Two patients recovered completely within 1 week and one complained of a slight impairment of short-term memory. Severe cerebral oedema, and herniation across the brainstem and cerebellum developed in the fourth patient, who died 15 days later. The presence of serum immunoglobulin M antibody against rubella virus was demonstrated in all four patients; one patient also had immunoglobulin M antibody against rubella virus in his cerebrospinal fluid. No virus could be isolated during post-mortem examination of the fourth patient.
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Abstract
The authors describe a previously unreported anatomical structure in the calcaneocuboid joint of the foot and discuss the clinical significance. Fibroadipose synovial folds or labra are present in different locations throughout the calcaneocuboid joint of the foot. They appear to be wedge-shaped infections attached to the joint capsule in areas of incongruent joint spaces. Their surface is covered with synovial cells with a highly vascular loose connective tissue sublayer. Nerve fibers were seen in association with the joint capsule, but not within the V-shaped labrum. The clinical significance of the presence of the labrum is discussed, but their function is uncertain. These structures can project up to half the joint distance and have the possibility of producing impingement syndromes, or even tears. Since they are covered with two to three layers of synoviocytes, they also have the ability to produce a synovitis. The labrum can be identified using MRI, and once their presence is known arthroscopic repair of these structures is theoretically possible.
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Chau TN, Lai ST, Lai JY, Yuen H. Haemolysis complicating acute viral hepatitis in patients with normal or deficient glucose-6-phosphate dehydrogenase activity. SCANDINAVIAN JOURNAL OF INFECTIOUS DISEASES 1998; 29:551-3. [PMID: 9571732 DOI: 10.3109/00365549709035892] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Haemolytic anaemia as a complication of acute hepatitis has been reported in up to 23% of patients. However, the incidence may rise up to 70-87% in patients who have glucose-6-phosphate dehydrogenase (G6PD) deficiency. Massive intravascular haemolysis with renal failure, hepatic encephalopathy and even death have been reported. In our retrospective study of patients with acute viral hepatitis, the overall incidence of acute haemolysis was 4% (17/434). Only 53% (9/17) of them had G6PD deficiency. Patients with acute haemolysis had a significantly higher peak bilirubin level and required more prolonged hospitalization. Since hepatitis A virus vaccination, unlike hepatitis B virus vaccination, is not yet recommended for routine immunization, we suggest subjects who are G6PD-deficient should be vaccinated against hepatitis A. In endemic areas of hepatitis A virus infection, universal immunization remains the definitive answer.
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Wang DM, Lin FC, Chen LY, Lai JY. Application of asymmetric TPX membranes to transdermal delivery of nitroglycerin. J Control Release 1998; 50:187-95. [PMID: 9685885 DOI: 10.1016/s0168-3659(97)00133-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
In this study, asymmetric poly(4-methyl-1-pentene) (TPX) membranes, fabricated by the dry/wet inversion method, were applied to transdermal delivery of nitroglycerin (NTG), a drug for treating angina pectoris. The flux of NTG through the TPX membrane was measured in vitro by a Franz cell. The results indicate that the NTG flux through asymmetric TPX membranes is strongly dependent on the membrane structure, which can be varied by adding nonsolvents in the casting solution. By adding different kinds of nonsolvents and adjusting the added amounts, membranes with different NTG release rates can be fabricated. It was also found that, with suitable drug formula, the NTG dissolution rate of a prototype TPX patch is comparable to that of a commercial patch, Transderm-Nitro. In addition, the data of NTG flux through a composite of TPX membrane and pig skin are also presented.
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Verdier-Pinard P, Lai JY, Yoo HD, Yu J, Marquez B, Nagle DG, Nambu M, White JD, Falck JR, Gerwick WH, Day BW, Hamel E. Structure-activity analysis of the interaction of curacin A, the potent colchicine site antimitotic agent, with tubulin and effects of analogs on the growth of MCF-7 breast cancer cells. Mol Pharmacol 1998; 53:62-76. [PMID: 9443933 DOI: 10.1124/mol.53.1.62] [Citation(s) in RCA: 223] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Originally purified as a major lipid component of a strain of the cyanobacterium Lyngbya majuscula isolated in Curaçao, curacin A is a potent inhibitor of cell growth and mitosis, binding rapidly and tightly at the colchicine site of tubulin. Because its molecular structure differs so greatly from that of colchicine and other colchicine site inhibitors, we prepared a series of curacin A analogs to determine the important structural features of the molecule. These modifications include reduction and E-to-Z transitions of the olefinic bonds in the 14-carbon side chain of the molecule; disruption of and configurational changes in the cyclopropyl moiety; disruption, oxidation, and configurational reversal in the thiazoline moiety; configurational reversal and substituent modifications at C13; and demethylation at C10. Inhibitory effects on tubulin assembly, the binding of colchicine to tubulin, and the growth of MCF-7 human breast carcinoma cells were examined. The most important portions of curacin A required for its interaction with tubulin seem to be the thiazoline ring and the side chain at least through C4, the portion of the side chain including the C9-C10 olefinic bond, and the C10 methyl group. Only two modifications totally eliminated the tubulin-drug interaction. The inactive compounds were a segment containing most of the side chain, including its two substituents, and analogs in which the methyl group at the C13 oxygen atom was replaced by a benzoate residue. Antiproliferative activity comparable with that observed with curacin A was only reproduced in compounds that were potent inhibitors of the binding of colchicine to tubulin. Molecular modeling and quantitative structure-activity relationship studies demonstrated that most active analogs overlapped extensively with curacin A but failed to provide an explanation for the apparent structural analogy between curacin A and colchicine.
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Chau TN, Lai ST, Lai JY, Yuen H. Acute viral hepatitis in Hong Kong: a study of recent incidences. Hong Kong Med J 1997; 3:261-266. [PMID: 11847370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
Acute hepatitis patients admitted to a referral centre from January 1995 through December 1995 were studied to determine the seroprevalence of the hepatitis viruses and related risk factors. Of the 434 patients with acute viral hepatitis, the episodes due to hepatitis A, B, C, D, and non-A, non-B, non-C, (non-ABC) were 214 (49.3%), 163 (37.6%), 7 (1.6%), 0 (0%), and 50 (11.5%), respectively. Acute hepatitis A and non-ABC hepatitis commonly occur in late spring and early summer and are probably related to the intake of shellfish and travel to endemic areas. Approximately 60% of cases of symptomatic hepatitis B infection were acute exacerbations of chronic infection. Sexual exposure was the single most important risk factor for acute hepatitis B infection. The rarity of acute hepatitis C and D might be related to the low rate of intravenous drug use in our locality. Hepatitis E virus probably contributed significantly to the cases of non-ABC hepatitis. Further studies are needed to establish the importance of various causative agents of acute hepatitis in Hong Kong.
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Ng CKM, Mak AYK, Au TS, Au TC, Lai ST, Lai JY. Plasmodium infection unmasked by corticosteroid therapy. Hong Kong Med J 1997; 3:328-330. [PMID: 11847382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
In the past four years, we have encountered three patients in whom malaria parasites were found incidentally in their blood when they were receiving corticosteroid therapy. Although there is little direct evidence that corticosteroid therapy can activate human malaria, animal studies have successfully demonstrated the recrudescence effect of immunosuppression on malaria infection.
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Sun YM, Huang JJ, Lin FC, Lai JY. Composite poly(2-hydroxyethyl methacrylate) membranes as rate-controlling barriers for transdermal applications. Biomaterials 1997; 18:527-33. [PMID: 9105591 DOI: 10.1016/s0142-9612(96)00166-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Composite membranes were prepared by casting a linear poly(2-hydroxyethyl methacrylate) (pHEMA) solution onto polyester non-woven supports, and then the supported pHEMA within the membranes was cross-linked by a diisocyanate cross-linking agent to form a network structure. The swelling and permeation properties of these membranes were evaluated, with a system of nitroglycerin and aqueous ethanol solution, for potential application in transdermal drug delivery. The degree of swelling of these membranes in water and aqueous ethanol decreases as the cross-linker content is increased and increases slightly with an increase in the original molecular weight of the linear pHEMA. The permeation rates of both nitroglycerin and ethanol increase as the cross-linker content is reduced, the polymer molecular weight increases, and the concentration of the casting solution or membrane thickness decreases. Depending on the preparation conditions, the membranes can be tailored to give a permeation flux ranging from 4 to 68 micrograms cm-2 h-1 for nitroglycerin.
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Lai JY. Hapatitis A and E in Hong Kong. Hong Kong Med J 1997; 3:79-82. [PMID: 11847359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
Acute viral hepatitis is one of the most prevalent infectious diseases in Hong Kong and hepatitis A accounts for two thirds or more of reported cases. Improved sanitation has led to a decline in hepatitis A infection in childhood but more clinically overt adult cases now occur. Shellfish ingestion and recent travel are important risk factors. A highly immunogenic and effective inactivated hepatitis A vaccine is available. Hepatitis E is of emerging importance as a cause of acute hepatitis. Large outbreaks have occurred in China and other developing countries; sporadic cases occur in Hong Kong. High mortality is associated with hepatitis E complicating late pregnancy. Serological diagnosis by enzyme immunoassay for anti-HEV is available. The education of travellers to endemic areas is advised with special caution being given to pregnant women. A vaccine for hepatitis E is not yet available.
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Lai JY, Sheu JC, Chang PY, Yeh ML, Chang CY, Chen CC. Experience with distal circular myotomy for long-gap esophageal atresia. J Pediatr Surg 1996; 31:1503-8. [PMID: 8943110 DOI: 10.1016/s0022-3468(96)90165-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
From 1980 to 1994, the authors treated 65 cases of esophageal atresia (with or without tracheoesophageal fistula). Among these patients, 15 (23%) underwent pure proximal circular myotomies and five (8%) underwent both proximal and distal circular myotomies. Of the latter five cases, three were Gross type C and two were Gross type A. The gap ranged from 4.5 cm to 6.5 cm (mean, 5 cm). Surgical complications in these five patients included two anastomotic leaks (40%), one anastomotic stricture (20%), and four gastroesophageal refluxes (80%). Three patients eventually underwent fundoplication as an antireflux procedure. Mucosal outpouching was noted in all cases. The myotomy did not adversely affect the esophageal peristalsis and motility on the esophagogram. Esophageal function was similar to that of other children who had esophageal atresia without myotomy. All patients could eat food typical for their age. This limited experience suggests that distal circular myotomy might be a safe adjuvant procedure to achieve primary anastomosis in long-gap esophageal atresia.
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de Boer WA, van Etten RJ, Lai JY, Schneeberger PM, van de Wouw BA, Driessen WM. Effectiveness of quadruple therapy using lansoprazole, instead of omeprazole, in curing Helicobacter pylori infection. Helicobacter 1996; 1:145-50. [PMID: 9398895 DOI: 10.1111/j.1523-5378.1996.tb00028.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND Omeprazole enhances the efficacy of bismuth-based triple therapy. It is unknown whether the same is true for other proton pump inhibitors. Lansoprazole has superior anti-Helicobacter activity in vitro and possibly also in vivo; therefore we investigated quadruple therapy with lansoprazole. MATERIALS AND METHODS In two studies performed in separate hospitals, a total of 67 Helicobacter pylori-positive patients were treated with 7-day quadruple therapy (lansoprazole, colloidal bismuth subcitrate, tetracycline, and metronidazole) after 3 days of lansoprazole pretreatment. Testing for cure was done by endoscopy in study 1 and by breath test in study 2. RESULTS Cure rates per protocol were 31 of 31 (100%) in study 1 and 30 of 32 (94%) in study 2. Intention-to-treat cure rates were 31 of 35 (89%) in study 1 and 30 of 32 (94%) in study 2. Cured overall were 32 of 34 with a metronidazole sensitive strain and 3 of 3 with a metronidazole-resistant strain. Data on side effects were collected from 51 patients. Twelve (21%) had no side effects, 27 (53%) had mild side effects, 10 (20%) had moderate side effects, but only 2 (4%) had severe side effects. Side effects, never were the reason that a patient stopped taking the medication. CONCLUSIONS The results with lansoprazole-quadruple therapy are comparable to the historic control group treated with omeprazole-quadruple therapy. The cure rare is very high, and although mild to moderate side effects occurred in many patients, everybody finished the treatment regime.
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Lai JY, De Boer WA, Driessen WM, Geuskens LM. Long-term follow-up after cure of Helicobacter pylori infection with 4 days of quadruple therapy. Aliment Pharmacol Ther 1996; 10:645-50. [PMID: 8853771 DOI: 10.1046/j.1365-2036.1996.43185000.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
BACKGROUND We have shown that 4 days of quadruple therapy after omeprazole pre-treatment is an effective therapy for curing H. pylori infection. In this study we investigated whether this regimen would maintain the high cure rate during long-term follow-up. Some recent studies have reported high recurrence rates after apparent cure. Apparently not all methods to test for cure have sufficient sensitivity to pick up small numbers of residual bacteria. This study also served to investigate whether our methods to test for cure 5-6 weeks post-treatment were reliable. METHODS All patients from a previous study were invited to return for a 14C-urea breath test and serology. A representative group of 37 patients (76%) returned for a urea breath test and serology. The mean follow-up was 14.7 months (range 11.4-23.6 months). RESULTS None of the 37 patients had a positive urea breath test results. IgG antibody titres fell steadily in all patients, showing a mean decrease of 83% at the end of the follow-up. None of the patients showed an increase in titre. Reinfection was therefore 0% (0 of 37). CONCLUSION Four days of quadruple therapy seems to be an effective therapy for the eradication of H. pylori as evidenced after long-term follow-up. Our biopsy methodology is reliable in identifying treatment failures 5-6 weeks post-treatment.
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Abstract
Cholera is one of the three diseases subject to the International Health Regulations. After a period of over 30 years, the seventh pandemic of cholera, which started in South East Asia in 1961, still shows no sign of a decline. On the contrary, it has increased its severity and invaded many other countries in Africa and Latin America. In the last two years, there has been a recrudescence of the disease in South East Asia and Western Pacific Regions. The discovery of a new strain of Vibrio cholerae 0139 in these regions is causing concern in view of its potential to cause major epidemics and higher mortality. Hong Kong had two intensive outbreaks of cholera in the last two years. The cause of these outbreaks was not clear, but adverse environmental conditions and increasing pollution of coastal waters have been implicated. The spread of cholera knows no geographical boundaries. There is a need for intensified efforts among health authorities in the affected areas to prevent the international spread of the disease.
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Jiang J, Sharma SD, Nakamura S, Lai JY, Fink JL, Hruby VJ, Hadley ME. The melanotropic peptide, [Nle4,D-Phe7] alpha-MSH, stimulates human melanoma tyrosinase activity and inhibits cell proliferation. PIGMENT CELL RESEARCH 1995; 8:314-23. [PMID: 8789740 DOI: 10.1111/j.1600-0749.1995.tb00680.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Seventeen human melanoma cell (HMC) lines, both melanotic and amelanotic, were incubated in the continuous presence of a potent melanotropic peptide hormone analog, [Nle4,D-Phe7] alpha-MSH, for 72 hr with daily changes of medium. Only one cell line (HD, melanotic) consistently responded to the hormone analog by increased tyrosinase activity. Three (one melanotic, two amelanotic) of the HMC lines also failed to respond to the peptide by either increased or decreased enzyme activity when incubated continuously in the presence of the peptide for longer periods of time (6,15,27,43 days). The HD cell line, however, again responded with increasingly enhanced basal enzyme activity the longer the cells were incubated in the presence of the melanotropin. One amelanotic cell line (C8161) responded with enhanced enzyme activity when grown to confluency in the continuous presence of the peptide. Basal tyrosinase activity of the C8161 cell line may have increased as cell density in the flasks increased. These results suggest that under conditions of increased cell number, phenotypic expression of tyrosinase activity in so called "amelanotic" (tyrosinase-negative) cells is increased and can be enhanced further by stimulation with a melanotropic peptide. Under conditions of increased cell number, the presence of [Nle4,D-Phe7] alpha-MSH caused morphological differentiation (shape change); the cells became enlarged and very dendritic. The number of cells in monolayer (surface of the flask) and in the medium were drastically reduced in both melanotic and "amelanotic" cell lines incubated with [Nle4,D-Phe7] alpha-MSH. The data support other published reports that melanotropic peptides inhibit human melanoma cell growth (proliferation) in vitro, most likely through a cytostatic mechanism. [Nle4,D-Phe7] alpha-MSH also exhibited a prolonged (residual) inhibitory action on HD cell proliferation. In other words, inhibition of cell growth (proliferation) of the HMCs was evident even several days after removal of the melanotropic peptide from the incubation medium.
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Lai JY, Shih CY, Lin FC. Plasma Deposition of Vinyl Monomers onto Poly(4-methyl-1-pentene)/Poly(dimethyl siloxane) Blend Membrane for Enrichment of Oxygen From Air. Polym J 1994. [DOI: 10.1295/polymj.26.665] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Shih CY, Lai JY. Polyvinyl alcohol plasma deposited nylon 4 membrane for hemodialysis. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 1993; 27:983-9. [PMID: 8408126 DOI: 10.1002/jbm.820270803] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Polyvinyl alcohol (PVA) is a hydrophilic and blood compatible material, but it is easily hydrolyzed in aqueous solution. Various methods, including chemical crosslinking and gamma-ray irradiation, have been investigated by many researchers for overcoming the instability of PVA in aqueous solution. This study suggests a new hemodialysis membrane, which is prepared by plasma depositing vinylacetate (VAc) onto annealled nylon 4 membrane, followed by hydrolysis treatment. This improves the blood compatibility of nylon 4 and overcomes the hydrolysis problem of PVA. In addition to conventional plasma deposition, the plasma initiated interpenetrating network (IPN) method is also investigated. The new hemodialysis membranes prepared by both conventional plasma deposited VAc onto nylon 4 (PPVA/N4) and IPN polymer of plasma initiated VAc onto nylon 4 (PIPVA/N4 IPN) show significant improvement in blood compatibility. However, the solute permeabilities of PIPVA/N4 IPN membranes are higher than those of PPVA/N4 membranes. The permeabilities of NaCl, vitamin B12, and albumin for membranes prepared by IPN at 80 W, 30 sec plasma deposited conditions, i.e., the optimized conditions, are 3.614, 0.070, and 0.000 x 10(-5) cm2/min, respectively. The mole ratio of adsorbed fibrinogen to adsorbed albumin (the mole ratio F/A) for this membrane is 0.20, and it also shows excellent blood compatibility in this study.
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Leung NW, Tam JS, Lai JY, Leung TW, Lau WY, Shiu W, Li AK. Does hepatitis C virus infection contribute to hepatocellular carcinoma in Hong Kong? Cancer 1992. [PMID: 1318777 DOI: 10.1002/1097-0142(19920701)70:1<40::aid-cncr2820700107>3.0.co;2-p] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND Hong Kong has a high incidence of hepatocellular carcinoma (HCC) and, because it is an endemic area for hepatitis B virus (HBV) infection, the etiologic association between HCC and HBV infection is reported to be as high as 80%. Hepatitis C virus (HCV) recently was shown to be a possible pathogenetic agent for HCC in a number of countries. METHODS To assess the relative importance of these two viruses in HCC in Hong Kong, a retrospective study of 424 Chinese patients with HCC was performed. RESULTS Three hundred forty-one (80.3%) patients were found to be carriers of hepatitis B surface antigen (HBsAg). Hepatitis C antibodies (anti-HCV) were detected in 31 patients (7.3%). Fifteen patients with positive findings for anti-HCV had concurrent HBV infection, 11 had serologic evidence of previous HBV infection, and only 5 patients had anti-HCV marker alone. Patients with positive findings for anti-HCV were older than those with HBsAg (mean ages, 60 and 53 years, respectively). A higher preponderance of male patients was found in the HBsAg-positive group; the male to female ratio was 11:1, compared with 7:1 among patients with anti-HCV. Anti-HCV was detected in 0.64% of 175 age-matched and sex-matched controls. CONCLUSIONS These data indicate a possible causal role of HCV infection in HCC, but it is of relatively minor epidemiologic significance in Hong Kong, where HBV infection is overwhelming.
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Abstract
BACKGROUND Hong Kong has a high incidence of hepatocellular carcinoma (HCC) and, because it is an endemic area for hepatitis B virus (HBV) infection, the etiologic association between HCC and HBV infection is reported to be as high as 80%. Hepatitis C virus (HCV) recently was shown to be a possible pathogenetic agent for HCC in a number of countries. METHODS To assess the relative importance of these two viruses in HCC in Hong Kong, a retrospective study of 424 Chinese patients with HCC was performed. RESULTS Three hundred forty-one (80.3%) patients were found to be carriers of hepatitis B surface antigen (HBsAg). Hepatitis C antibodies (anti-HCV) were detected in 31 patients (7.3%). Fifteen patients with positive findings for anti-HCV had concurrent HBV infection, 11 had serologic evidence of previous HBV infection, and only 5 patients had anti-HCV marker alone. Patients with positive findings for anti-HCV were older than those with HBsAg (mean ages, 60 and 53 years, respectively). A higher preponderance of male patients was found in the HBsAg-positive group; the male to female ratio was 11:1, compared with 7:1 among patients with anti-HCV. Anti-HCV was detected in 0.64% of 175 age-matched and sex-matched controls. CONCLUSIONS These data indicate a possible causal role of HCV infection in HCC, but it is of relatively minor epidemiologic significance in Hong Kong, where HBV infection is overwhelming.
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Lai JY, Tam JS, Lam LY, Leung NW. Prevalence of antibody to hepatitis C virus in HBsAg-negative chronic liver disease in Hong Kong using different assays. J Med Virol 1992; 37:158-60. [PMID: 1321225 DOI: 10.1002/jmv.1890370215] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The prevalence of anti-HCV antibodies in Chinese patients with HBsAg-negative chronic liver diseases was studied retrospectively. Anti-HCV was detected by two different ELISAs. In 97 patients with HBsAg-negative chronic liver disease, 26 (27%) were anti-HCV positive. Of 157 control subjects, only 1 (0.6%) was anti-HCV positive (P less than 0.001). Anti-HCV was detected in 18 of 27 (67%) patients with post-transfusion non-A, non-B (PTNANB) chronic hepatitis or cirrhosis, 5 of 25 (20%) patients with cryptogenic chronic hepatitis or cirrhosis, 2 of 33 (6%) patients with alcoholic liver disease, 1 of 5 (20%) patients with autoimmune chronic active hepatitis (AICAH), none of 4 patients with primary biliary cirrhosis (PBC), and none of 3 patients with fatty liver. The prevalence in this group of patients was lower when compared to reports from other countries. The addition of a urea washing step reduced false-positivity in alcoholic and AICAH groups. The ELISA that employs three recombinant HCV antigens confirmed all positive results by another ELISA with the exception of one weakly positive result in the AICAH group and one in the alcoholic group. One patient in the PTNANB group was detected in addition by the second generation assay. In conclusion, ELISA with a urea wash proved to be useful in reducing false-positivity, and the second generation assay proved to be a sensitive and specific test for anti-HCV antibody.
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Lai JY, Linden W. Gender, anger expression style, and opportunity for anger release determine cardiovascular reaction to and recovery from anger provocation. Psychosom Med 1992; 54:297-310. [PMID: 1620806 DOI: 10.1097/00006842-199205000-00006] [Citation(s) in RCA: 78] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
This study represents an extension of Hokanson's research, which showed that for men anger release after provocation tends to accelerate cardiovascular recovery. The objective of this study was to investigate how gender and habitual style for anger-in or anger-out behavior modulate the effect of anger provocation and release. Male and female subjects (N = 105) were classified as anger-in/anger-out only when a double criterion (i.e., self-report and peer evaluation) was satisfied. Following a state anger rating at pre-test, subjects were harassed during the performance of a 12-minute math task. After task completion, subjects were randomly assigned to one of two 10-minute recovery protocols a) having an opportunity to release negative affect, and b) not not having such an opportunity. All groups (including the anger-ins) that had an opportunity to express negative affect did in fact express similar levels of anger. Men reacted more strongly to the math task performed under anger provocation on all cardiovascular indices. Anger expression style as a trait-type disposition was important for the recovery process in women whereas the situational manipulation (i.e., the opportunity to release anger) had specific effects on the recovery process of men. Opportunity to release anger facilitated heart rate recovery (and to a lesser degree diastolic pressure recovery) in men but not in women. Women with anger-in tendencies on the other hand displayed better systolic pressure recovery than female anger-outs whereas no such effects were observed in men.
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Barth JD, Blankenhorn DH, Wickham E, Lai JY, Chin HP, Selzer RH. Quantitative ultrasound pulsation study in human carotid artery disease. ARTERIOSCLEROSIS (DALLAS, TEX.) 1988; 8:778-81. [PMID: 3058103 DOI: 10.1161/01.atv.8.6.778] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Pulsation in the human carotid artery during two complete cardiac cycles was studied by using computer digitized video-frames from B-mode ultrasound images. Eight patients with identifiable atherosclerotic lesions in the common carotid immediately proximal to the bulb area were studied. Diameter, strain, and elastic modulus were compared between lesion site and an adjacent reference segment 1 or 2 cm proximal to the bulb. As controls, nine patients without identifiable lesions were analyzed. The results indicate a significantly wider diameter (p less than 0.01) at the proximal reference site in patients with lesions as compared to comparable segments in control patients. The strain was significantly lower (p less than 0.05), whereas the elastic modulus was significantly higher (p less than 0.05), at the lesion site as compared to the proximal reference sites in patients with lesions. These results may indicate that an initial dilation of the carotid artery followed by loss of wall flexibility may be associated with atherosclerotic lesion formation.
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Abstract
A random telephone survey was completed with 253 adults to explore a possible relationship between death anxiety and public attitudes toward prospective use of hospice services. Among these adults, death anxiety does not appear to be related to attitudes toward prospective personal use of hospice services, although a desire to prolong life may be related to specific items within the Templer Death Anxiety Scale.
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