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Seleena P, Lee HL, Nazni WA, Rohani A, Kadri MS. Microdroplet application of mosquitocidal Bacillus thuringiensis using ultra-low-volume generator for the control of mosquitos. THE SOUTHEAST ASIAN JOURNAL OF TROPICAL MEDICINE AND PUBLIC HEALTH 1996; 27:628-32. [PMID: 9185282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
In an effort to develop a more effective technique in dispersing a microbial control agent, Bacillus thuringiensis (Bt), a truck-mounted ultra low volume (ULV) generator (Scorpion) was used to disperse B. thuringiensis israelensis (Bti) and Bti with malathion. Complete larval and adult mortalities for all tested mosquito species within the first 70-80 feet from the ULV generator were achieved. Beyond that distance less than 50% mortality was achieved as insufficient sprayed particles reached the area. A minimum of 10(3) Bti colony forming units per ml is required to cause 100% larval mortality. The sprayed Bti larvicidal toxins were persistent in the test water 7 days post ULV. The effectiveness of B. thuringiensis jegathesan (Btj), a new mosquitocidal Bt serotype was also evaluated. Similar mortality results as Bti were achieved except that the Btj toxins underwent degradation in the test water, since less than 50% less in larval mortality was observed in 7 days post ULV samples. This ULV method has the potential to disperse Bt and malathion effectively for a simultaneous control of mosquito adults and larvae.
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177
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Chuang CC, Wang SR, Lee HL. Bronchial responsiveness of aged asthmatic patients to bronchodilator and methacholine. Asian Pac J Allergy Immunol 1996; 14:1-4. [PMID: 8980792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Geriatric asthma is characterized by prolonged illness, lower remission rate, poor response to therapy and higher mortality rate. We studied bronchodilator response and methacholine challenge in 25 aged non-smoking asthmatic patients; thirty-two young asthmatic patients were included as control. The elderly patients had poorer baseline pulmonary function and were more responsive to a bronchodilator than the younger patients. The response to bronchoprovocation did not show any difference between the two groups. Our findings suggested that the airways of elderly asthmatics are as sensitive as those of younger patients and should not be under-treated.
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Seleena P, Lee HL, Lecadet MM. A new serovar of Bacillus thuringiensis possessing 28a28c flagellar antigenic structure: Bacillus thuringiensis serovar jegathesan, selectively toxic against mosquito larvae. JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION 1995; 11:471-473. [PMID: 8825511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
A novel Bacillus thuringiensis strain highly toxic to mosquitoes was isolated from soil samples in Malaysia. This strain was shown to display a new subfraction of the H-28 flagellar antigen determining a new serovar H28a28c, which was designated serovar jegathesan. Bioassays indicated that Culex quinquefasciatus larvae are the most susceptible to this new isolate, whereas toxicity to Anopheles maculatus and Aedes aegypti larvae was 10 times lower. The potency of this new serotype is also comparable to most of the Malaysian B. thuringiensis H-14 isolates.
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179
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Lee HL, Chandrawathani P, Wong WY, Tharam S, Lim WY. A case of human enteric myiasis due to larvae of Hermetia illucens (Family: Stratiomyiadae): first report in Malaysia. THE MALAYSIAN JOURNAL OF PATHOLOGY 1995; 17:109-11. [PMID: 8935136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
A case of true enteric myiasis in a 7-year-old girl is reported. Two larvae were obtained from the vomitus of the patient. After processing and identification, the larvae were found to be those of Hermetia illucens (Soldier Fly). This is the first case of true enteric myiasis due to these larvae in Malaysia.
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Kawalek MD, Benjamin S, Lee HL, Gill SS. Isolation and Identification of novel toxins from a new mosquitocidal isolate from Malaysia, Bacillus thuringiensis subsp. jegathesan. Appl Environ Microbiol 1995; 61:2965-9. [PMID: 7487029 PMCID: PMC167573 DOI: 10.1128/aem.61.8.2965-2969.1995] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
A new mosquitocidal Bacillus thuringiensis subsp., jegathesan, has recently been isolated from Malaysia. Parasporal crystal inclusions were purified from this strain and bioassayed against fourth-instar larvae of Culex quinquefasciatus, Aedes aegypti, Aedes togoi, Aedes albopictus, Anopheles maculatus, and Mansonia uniformis. The 50% lethal concentration of crystal inclusions for each species was 0.34, 8.08, 0.34, 17.59, 3.91, and 120 ng/ml, respectively. These values show that parasporal inclusions from this new subspecies have mosquitocidal toxicity comparable to that of inclusions isolated from B. thuringiensis subsp. israelensis. Solubilized and chymotrypsin-activated parasporal inclusions possessed low-level hemolytic activity. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that the crystals were composed of polypeptides of 77, 74, 72, 68, 55, 38, 35, 27, and 23 kDa. Analysis by Western blotting (immunoblotting) with polyclonal antisera raised against toxins purified from B. thuringiensis subsp. israelensis reveals that proteins in parasporal inclusions of subsp. jegathesan are distinct, because little cross-reactivity was shown. Analysis of the plasmid content of B. thuringiensis subsp. jegathesan indicates that the genes for toxin production may be located on 105- to 120-kb plasmids. Cry- clones that have been cured of these plasmids are nontoxic. Southern blot analysis of plasmid and chromosomal DNA from subsp. jegathesan showed little or low homology to the genes coding for CryIVA, CryIVB, and CryIVD from B. thuringiensis subsp. israelensis.
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181
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Archer TK, Fryer CJ, Lee HL, Zaniewski E, Liang T, Mymryk JS. Steroid hormone receptor status defines the MMTV promoter chromatin structure in vivo. J Steroid Biochem Mol Biol 1995; 53:421-9. [PMID: 7626491 DOI: 10.1016/0960-0760(95)00088-h] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The ability to respond to small signalling molecules such as steroid hormones is important for many physiological processes. Steroid hormones act through a group of high affinity receptors that regulate transcription by binding to hormone response elements (HREs) located within the promoters of target genes, which themselves are organized with nuclear proteins to form chromatin. To dissect the mechanisms(s) of steroid hormone action we have used the steroid inducible mouse mammary tumor virus (MMTV) promoter as a model system. The MMTV promoter is assembled into a phased array of nucleosomes that are specifically positioned in rodent cells. Induction of transcription by glucocorticoids is accompanied by the appearance of a hypersensitive region in the proximal promoter which allows the hormone dependent assembly of a preinitiation complex including transcription factors such as nuclear factor 1 (NF1) and the octamer transcription factor (OTF). Surprisingly, when introduced by transient transfection, the progesterone receptor (PR) is unable to activate this promoter in vivo, a finding that may result from its inability to alter MMTV promoter chromatin. In an attempt to investigate the failure of the PR to activate the promoter, we have stably introduced the MMTV promoter into human T47D breast cancer cells that express high levels of the PR. In contrast to what has been observed previously in rodent cells, the MMTV templates resident in human breast cancer cells adopt a novel and constitutively open chromatin structure. The constitutively open chromatin structure is accompanied by the hormone independent loading of transcription factors including the PR and NF1. In T47D cells that stably express the glucocorticoid receptor, the MMTV promoter responds to glucocorticoids, but not progestins, and displays glucocorticoid induced restriction enzyme hypersensitivity and transcription factor loading. These findings suggest that the organization of the MMTV chromatin structure is dependent upon the cell type and receptor status of the recipient cell into which the MMTV promoter is stably introduced.
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182
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Lee HL, Chong WL. Glutathion S-transferase activity and DDT-susceptibility of Malaysian mosquitos. THE SOUTHEAST ASIAN JOURNAL OF TROPICAL MEDICINE AND PUBLIC HEALTH 1995; 26:164-7. [PMID: 8525405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Comparative DDT-susceptibility status and glutathion s-transferase (GST) activity of Malaysian Anopheles maculatus, Culex quinquefasciatus and Aedes aegypti was investigated to ascertain the role of this enzyme in DDT resistance. The standardised WHO dose-mortality bioassay tests were used to determine DDT susceptibility in these mosquitos, whilst GST microassay (Brogdon and Barber, 1990) was conducted to measure the activity of this enzyme in mosquito homogenate. It appeared that DDT susceptibility status of Malaysian mosquitos was not correlated with GST activity.
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183
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Abstract
Primary localized amyloidosis is a rare disease with an excellent prognosis in most cases. We report a case of primary localized amyloidosis of the bladder that was treated with transurethral resection.
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184
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Lee HL, Tadano T. Monitoring resistance gene frequencies in Malaysian Culex quinquefasciatus Say adults using rapid non-specific esterase enzyme microassays. THE SOUTHEAST ASIAN JOURNAL OF TROPICAL MEDICINE AND PUBLIC HEALTH 1994; 25:371-3. [PMID: 7855659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The ability to identify the occurrence of different resistance genotypes in field populations of mosquito is considered important for the purpose of optimising chemical control operations. The recent development of rapid microassays of enzymes responsible for resistance has provided a means for rapidly assessing the genetic background of target mosquito populations. This concept is the topic of investigation in this study. Non-specific esterase activity, which is responsible for the resistance to organophosphates in Malaysian Culex quinquefasciatus Say adults, was determined in 3 field populations from Kuala Lumpur City using rapid enzyme assay. The optical density results were used to estimate the genotypic frequencies of the populations. Subsequently, time-dependent changes in the various frequencies were determined. Such techniques allowed rapid assessment of resistance genotypes for decision-making and its possible use in insect control merits further investigation.
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185
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Seleena P, Lee HL. Absence of plasmid in mosquitocidal Clostridium bifermentans serovar malaysia. THE SOUTHEAST ASIAN JOURNAL OF TROPICAL MEDICINE AND PUBLIC HEALTH 1994; 25:394-6. [PMID: 7855665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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186
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Archer TK, Lee HL, Cordingley MG, Mymryk JS, Fragoso G, Berard DS, Hager GL. Differential steroid hormone induction of transcription from the mouse mammary tumor virus promoter. Mol Endocrinol 1994; 8:568-76. [PMID: 8058066 DOI: 10.1210/mend.8.5.8058066] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The Mouse Mammary Tumor Virus (MMTV) contains sequences in its proximal promoter region to which both glucocorticoid and progesterone receptors can bind. In transient transfection experiments both hormones are able to stimulate transcription from reporter plasmids containing either native or consensus hormone response elements (glucocorticoid response element/progesterone response element). Previous experiments have demonstrated that the MMTV long terminal repeat is reproducibly assembled into a phased array of nucleosomes when stably introduced into cells. Stimulation by glucocorticoids of endogenous templates led to a rapid but transient increase in transcription initiation and mRNA accumulation that can be correlated with increased sensitivity to restriction enzymes. In contrast, experiments using progesterone or a truncated glucocorticoid receptor failed to elicit a similar increase in mRNA levels as dexamethasone from stable chromatin templates. In an attempt to understand this differential response, we have compared the responsiveness of the MMTV promoter to glucocorticoids and progesterone when it is organized in either stable chromatin or in transiently acquired plasmids. Our results demonstrate that the native chromatin structure prevents activation of this locus by progesterone, but permits stimulation by glucocorticoids.
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188
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Hong D, Heiman AS, Kwon T, Lee HL. Synthesis of 6-(methoxycarbonyl)prednisolone and its derivatives as new antiinflammatory steroidal antedrugs. J Pharm Sci 1994; 83:357-61. [PMID: 8207681 DOI: 10.1002/jps.2600830318] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The synthesis and pharmacological evaluation of 6-(methoxycarbonyl)prednisolone (11) (a 3:1 mixture of 6 alpha-isomer 11a and 6 beta-isomer 11b), its 21-ol acetates 13a (6 alpha-isomer) and 13b (6 beta-isomer), and 17,21-diol acetonide 14 (a 6:1 mixture of 6 alpha-isomer 14a and 6 beta-isomer 14b) as local antiinflammatory steroidal antedrugs are described. The lead compound 11 was prepared via 12 steps from hydrocortisone (1). In the croton oil-induced ear edema assay, the topical antiinflammatory activity of 13a was higher than that of its epimer 13b. Except for 13a, the compounds (11, 13b, and 14) showed less activity than prednisolone. The systemic activities were assessed after 5 days of consecutive administration of these compounds at equiactive doses. Neither 11 nor 14 depressed plasma corticosteroid levels or significantly altered adrenal weights. Thymic involution was absent for 14, 15% for 11, and 47% for prednisolone at the equiactive doses. Both 13a and 13b showed significant reduction of adverse systemic effects assessed as the increase of body weight and the decreases of adrenal and thymus weights. The putative metabolite, carboxylic acid 12, showed 26 times less topical antiinflammatory activity than prednisolone. These results suggest that introduction of a labile methoxycarbonyl group at the C-6 position of prednisolone results in retention of antiinflammatory activity while reducing systemic effects noted following topical application of the parent compound prednisolone.
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189
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Chang SG, Lee JH, Hong DH, Lee HL, Chai SE, Hoffman RM. Comparison of glucose-consumption and thymidine-incorporation endpoints in histocultured human superficial bladder tumors. Anticancer Res 1994; 14:77-83. [PMID: 8166460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Glucose consumption and tritiated thymidine incorporation were monitored for 54 days in histocultured human superficial transitional cell carcinoma of the bladder, indicating that long-term histoculture of human transitional cell carcinoma of the bladder is feasible. The glucose-consumption rate was relatively similar among the histocultured specimens and depended on the size of the explant in histoculture. Tritiated thymidine incorporation, on the other hand, varied greatly between the histocultured specimens. In addition, [3H]thymidine incorporation varied in single histocultures between cells in the original explant and those invading the gel. From these results, we conclude that the glucose consumption rate in histocultured human superficial bladder tumor is more reliable and sensitive than thymidine incorporation. The glucose-consumption endpoint is simple to measure and nondestructive, allowing multiple measurements on a single culture, unlike the thymidine incorporation endpoint.
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190
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Lee HL, Archer TK. Nucleosome-mediated disruption of transcription factor-chromatin initiation complexes at the mouse mammary tumor virus long terminal repeat in vivo. Mol Cell Biol 1994; 14:32-41. [PMID: 8264599 PMCID: PMC358353 DOI: 10.1128/mcb.14.1.32-41.1994] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Glucocorticoid induction of mouse mammary tumor virus (MMTV) is short lived, returning to base levels within 24 h despite the continued presence of hormone. MMTV DNA sequences assembled as chromatin require hormone for binding by nuclear factor 1 (NF1) and octamer proteins (OCT). However, in the same cells, NF1 and OCT factors are bound to transiently introduced DNA in the absence of hormone. In contrast, recruitment of the TATA-binding protein and a novel DNA-binding protein, which we have designated FDT, for factor downstream of the TATA-binding protein, is hormone dependent for both stable and transient templates. Furthermore, transient DNA templates, but not nucleosomal templates, retain these transcription factors over the course of 24 h. This finding suggests that MMTV chromatin structure contributes to activation and cessation of transcription in vivo.
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MESH Headings
- Animals
- Base Sequence
- CCAAT-Enhancer-Binding Proteins
- Cell Line, Transformed
- Chromatin/metabolism
- DNA Primers/genetics
- DNA, Viral/genetics
- DNA, Viral/metabolism
- DNA-Binding Proteins/metabolism
- Dexamethasone/pharmacology
- Kinetics
- Mammary Tumor Virus, Mouse/genetics
- Mammary Tumor Virus, Mouse/metabolism
- Mice
- Molecular Sequence Data
- NFI Transcription Factors
- Nuclear Proteins
- Nucleosomes/metabolism
- Promoter Regions, Genetic/drug effects
- RNA, Messenger/biosynthesis
- RNA, Messenger/genetics
- Repetitive Sequences, Nucleic Acid
- TATA-Box Binding Protein
- Transcription Factors/metabolism
- Transcription, Genetic
- Y-Box-Binding Protein 1
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191
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Yim SY, Cho KJ, Park CI, Yoon TS, Han DY, Kim SK, Lee HL. Effect of wheelchair ergometer training on spinal cord-injured paraplegics. Yonsei Med J 1993; 34:278-86. [PMID: 8259705 DOI: 10.3349/ymj.1993.34.3.278] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The purpose of this study was to investigate the effect of wheelchair ergometer training on spinal cord-injured paraplegics. Eleven male paraplegics with a mean age of 30.9 years (range, 20 to 49 years) participated in the wheelchair ergometer training for the period of 5 weeks. The mean peak heart rate, the mean peak systolic blood pressure and the mean time required for 100m wheelchair propelling at resistance level 1 were significantly decreased at the end of 5 weeks of training as compared with those at pre-training. There was no statistically significant difference in pulmonary function test at pre- and post-training. The peak torque of shoulder flexor and the total work of shoulder flexor and extensor at 180 degrees/sec after training were increased more significantly than those prior to the training. In accordance with the findings as revealed above, it is deemed that the endurance and strength of the upper body and the cardiac fitness for spinal cord-injured paraplegics may be improved by the wheelchair ergometer exercise.
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192
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Seleena P, Lee HL. Antagonistic activities of mosquito larvicidal Bacillus sphaericus (Neide) against some pathogenic bacteria. Indian J Med Res 1993; 97:83-4. [PMID: 8505080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Mosquitocidal strains of B. sphaericus serotype H-5a5b were shown for the first time to exhibit antagonistic activities against several human pathogens especially Salmonella. These strains of B. sphaericus also exhibited high larval toxicity against several mosquitoes.
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193
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Vythilingam I, Chiang GL, Lee HL, Singh KI. Bionomics of important mosquito vectors in Malaysia. THE SOUTHEAST ASIAN JOURNAL OF TROPICAL MEDICINE AND PUBLIC HEALTH 1992; 23:587-603. [PMID: 1363679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/25/2023]
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194
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Chen CL, Yang SF, Goo TS, Chou WK, Tsai MH, Lee HL. [The efficacy of intravenous fentanyl patient-controlled analgesia for postoperative pain relief]. MA ZUI XUE ZA ZHI = ANAESTHESIOLOGICA SINICA 1992; 30:251-8. [PMID: 1344240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/25/2023]
Abstract
The safety and efficacy of patient-controlled analgesia used for postoperative pain relief were evaluated. Cumulative 24-hour requirements were analyzed for possible correlation with patient characteristics. All patients who used a patient-controlled analgesia device for postoperative pain relief were reviewed from June to October 1991. The device Baxter's basal/bolus infusor with patient control module, was used to deliver fentanyl in 379 patients. The fentanyl requirement, verbal analog pain score, first passage of flatus, side effects, sedative score, and degree of satisfaction were examined. The fentanyl requirement during the first 24 hours after operation was analyzed with regard to age, body weight, and sex. The daily fentanyl consumption in the first three postoperative days was 928 +/- 352 micrograms (n = 338), 553 +/- 259 micrograms (n = 220), and 490 +/- 222 micrograms (n = 71), respectively. The requirement for fentanyl during the first 24 hours after surgery was significantly higher than for the next two days (p-value < 0.001). Fentanyl consumption correlated well with body weight, and inversely with age. No difference was found between fentanyl consumption and sex (p-value = 0.4687). The mean time to the first passage of flatus in patients with abdominal surgery was 54.6 +/- 26.4 hours. The incidence of nausea, vomiting, and dizziness was similar, about 20% of patients. Itching was noted in 7% of patients. Oversedation (class 4) was found in three patients during the first operative day, the sedative score for other patients were around class 1-3. No patient exhibited signs of respiratory depression or withdrawal syndrome.(ABSTRACT TRUNCATED AT 250 WORDS)
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195
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Lee HL, Abimbola O, Singh KI. Determination of insecticide susceptibility in Culex quinquefasciatus Say adults by rapid enzyme microassays. THE SOUTHEAST ASIAN JOURNAL OF TROPICAL MEDICINE AND PUBLIC HEALTH 1992; 23:458-63. [PMID: 1488701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Rapid enzyme microassays for the detection of resistance due to organophosphate and carbamate in individual field-collected strains of Culex quinquefasciatus adults were conducted. These tests allowed accurate differentiation by eye, on the basis of color changes of susceptible and resistant individuals. Two separate tests were conducted for the biochemical assays. In the insensitive acetylcholinesterase (AChE) test, acetylthiocholine iodide (ACTH) and 5,5-dithiobis-(2-nitrobenzoic acid) (DTNB) were used as substrate and coupling agent respectively. The resulting yellow chromophore indicated AChE activity. Test results showed that the color intensity decreased as increasing concentrations of propoxur were added, thereby confirming the susceptibility of the enzyme to inhibitor. Assay of non-specific esterase however, indicated elevated levels which were correlated with degree of malathion resistance. Electrophoretic data revealed the presence of 2 esterase bands in all strains. It was concluded that such a pattern was not contributory to malathion resistance in adults.
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196
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Lee HL, Yong YK. Human aural myiasis. THE SOUTHEAST ASIAN JOURNAL OF TROPICAL MEDICINE AND PUBLIC HEALTH 1991; 22:274-5. [PMID: 1948291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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197
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Lee HL, Seleena P. Fermentation of a Malaysian Bacillus thuringiensis serotype H-14 isolate, a mosquito microbial control agent utilizing local wastes. THE SOUTHEAST ASIAN JOURNAL OF TROPICAL MEDICINE AND PUBLIC HEALTH 1991; 22:108-12. [PMID: 1948250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
A screening program searching for indigenous microbial control agents of mosquitos in Malaysia is initiated since 1987 and to date at least 20 isolates of mosquitocidal Bacillus thuringiensis serotypes have been obtained. Preliminary field evaluation of several isolates indicated that they are highly effective in the control of medically important mosquito species. For operational purposes, there is an urgent need to produce this agent utilizing cheap and locally available wastes through fermentation biotechnology. Fermentation studies in shake-flasks containing standard nutrient broth and soya bean waste, respectively, indicate that it takes about 37 hours for a Malaysian isolate of B. thuringiensis serotype H-14 to mature. In the grated coconut waste, fishmeal and rice bran, the bacteria took 28 hours, 26 hours and 126 hours respectively to mature. The endotoxin was harvested from the standard nutrient broth at 55 hours and at 50 hours from soybean, grated coconut waste and fishmeal. The endotoxin could only be harvested 150 hours after inoculation from rice bran medium. However, no bacterial growth was detected in palm oil effluent. In terms of endotoxin and biomass production, fishmeal appears to be a suitable medium. Variations in the pH of the fermenting media were also noted.
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198
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Chong JL, Chin EY, Chan SY, Lee HL, Thomas E. Denitrogenation in pregnant women. Singapore Med J 1990; 31:327-30. [PMID: 2255927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Forty-five pregnant females were studied with respect to the effectiveness of denitrogenation by the 3, 5, 7 and 9 rapid vital capacity breaths, and 3 to 5 minutes of normal breathing. It was found that 3 to 9 vital capacity breaths cannot effectively denitrogenate a pregnant patient when a circle breathing system with a gas flow of 8 litres/min is used. At least 3 minutes of normal tidal volume breathing should be given for proper denitrogenation or preoxygenation if the circle system is used for such a purpose.
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199
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Lee HL, Seleena P. Isolation of indigenous larvicidal microbial control agents of mosquitos: the Malaysian experience. THE SOUTHEAST ASIAN JOURNAL OF TROPICAL MEDICINE AND PUBLIC HEALTH 1990; 21:281-7. [PMID: 2237596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
A nationwide screening program searching for microbial control agents of mosquitos was initiated in Malaysia in 1986. A total of 725 samples were collected and 2,394 bacterial colonies were isolated and screened for larvicidal activity. From such screening, 20 Bacillus thuringiensis, 6 B. sphaericus, 1 Clostridium bifermentans and 2 Pseudomonas pseudomallei larvicidal isolates were obtained. Of these, a new B. thuringiensis named as subspecies malaysianensis was found, while the C. bifermentans was also a new anaerobe individualized as serovar malaysia. It was concluded that this screening program was highly successful.
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200
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Lee HL, Seleena P. Preliminary field evaluation of a Malaysian isolate of Bacillus thuringiensis serotype H-14 against Culex pseudovishnui. THE SOUTHEAST ASIAN JOURNAL OF TROPICAL MEDICINE AND PUBLIC HEALTH 1990; 21:143-4. [PMID: 2402673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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