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Chiang CH, Wang SS, Chang YC, Chiang CH, Chen CY, Chen YJ, See XY, Peng CY, Hsia YP, Chiang CH, Peng CM. The Effect of Renin-Angiotensin-Aldosterone System Inhibitors on Outcomes of Patients Treated with Immune Checkpoint Inhibitors: a Retrospective Cohort Study. Clin Oncol (R Coll Radiol) 2023; 35:446-453. [PMID: 36894383 DOI: 10.1016/j.clon.2023.02.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 01/07/2023] [Accepted: 02/22/2023] [Indexed: 03/05/2023]
Abstract
AIMS Renin-angiotensin-aldosterone system inhibitors (RAASi) are associated with improved survival outcomes in patients receiving immune checkpoint inhibitors (ICIs), but the data on the response to treatment and tumour-based endpoints across different tumour types are unknown. MATERIALS AND METHODS We carried out a retrospective study at two tertiary referral centres in Taiwan. All adult patients treated with ICIs between January 2015 and December 2021 were included. The primary outcome was overall survival and the secondary outcomes were progression-free survival (PFS) and clinical benefit rates. RESULTS In total, 734 patients were enrolled in our study, of which 171 were RAASi users and 563 were non-users. Compared with non-users, RAASi users had a longer median overall survival [26.8 (interquartile range 11.3-not reached) versus 15.2 (interquartile range 5.1-58.4) months, P < 0.001] and PFS [12.2 (interquartile range 3.9-34.5) versus 5.0 (interquartile range 2.2-15.2) months, P < 0.001]. In univariate Cox proportional hazard analyses, the use of RAASi was associated with a 40% reduction in the risk of mortality [hazard ratio 0.58 (95% confidence interval 0.44-0.76), P < 0.001] and disease progression [hazard ratio 0.62 (95% confidence interval 0.50-0.77), P < 0.001]. The association remained significant after adjusting for underlying comorbidities and cancer therapy in multivariate Cox analyses. A similar trend was observed for PFS. Furthermore, RAASi users experienced a greater clinical benefit rate than non-users (69% versus 57%, P = 0.006). Importantly, the use of RAASi before ICI initiation was not associated with improved overall survival and PFS. RAASi were not associated with an increased risk of adverse events. CONCLUSION The use of RAASi is associated with improved survival outcomes, treatment response and tumour-based endpoints in patients undergoing immunotherapy.
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Chiang CH, Lee GH, Chiang TH, Tang PU, Fang CT. Disseminated Mycobacterium avium complex infection as a differential diagnosis of tuberculosis in HIV patients. Int J Tuberc Lung Dis 2021; 24:922-927. [PMID: 33156759 DOI: 10.5588/ijtld.19.0602] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND: Disseminated Mycobacterium avium complex infection (DMAC) has symptoms and microscopic findings similar to those of TB in HIV patients. To inform a clinical algorithm-based differential diagnosis, we aimed to characterise the clinical features of DMAC.METHODS: This was a retrospective cohort study of 192 HIV-positive patients with culture-confirmed mycobacterial infections hospitalised during 1996-2016 at a major HIV/AIDS treatment centre in Taiwan.RESULTS: HIV patients with DMAC (n = 58) had a three times higher 1-year mortality than those with TB (n = 98) (48.3% vs. 16.3%, P < 0.001). DMAC and TB were not distinguishable by the WHO TB screening criteria (fever, cough, night sweats or weight loss). Nevertheless, DMAC was characterised by a lower median CD4 count (5.0 cells/µL vs. 38.5 cells/µL, P < 0.001), lower median body mass index (BMI) (17.7 kg/m² vs. 19.7 kg/m², P = 0.002) and the absence of chest radiographic findings (P < 0.001). Simultaneous presence of CD4 <20 cells/µl, BMI <18.5 kg/m² and negative chest radiographic finding had a 98% specificity for diagnosing DMAC against TB or other types of mycobacterial infections.CONCLUSION: DMAC is an important differential diagnosis of TB in HIV patients. A simple rule based on CD4, BMI and chest radiography may inform the decision to start anti-DMAC treatment in patients with mycobacterial infection.
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Tsai MH, Chiu CY, Shih HJ, Liao SL, Hua MC, Huang SH, Yao TC, Lai SH, Huang TS, Yeh KW, Chen LC, Su KW, Lim WH, Chang YJ, Chiang CH, Huang SY, Huang JL. Longitudinal investigation of nasopharyngeal methicillin-resistant Staphylococcus aureus colonization in early infancy: The PATCH birth cohort study. Clin Microbiol Infect 2016; 23:121.e1-121.e7. [PMID: 27793735 DOI: 10.1016/j.cmi.2016.10.020] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2016] [Revised: 09/01/2016] [Accepted: 10/13/2016] [Indexed: 11/30/2022]
Abstract
OBJECTIVES The study aimed to determine the long-term Staphylococcus aureus colonization patterns and strain relatedness, and the association between maternal and infant colonization in infancy. METHODS A birth cohort study was conducted from January 2012 to November 2014. Nasopharyngeal swabs for S. aureus detection were collected from infants at the age of 1, 2, 4, 6 and 12 months and from mothers when their children were 1-month-old. RESULTS In total, 254 samples were collected at each planned visit during the first 12-month study. The prevalence of S. aureus colonization decreased in the first year of life, ranging from 61.0% (155/254) at the age of 1 month to 12.2% (31/254) at 12 months. Persistent colonization, defined as a positive culture on four or five occasions, was detected in only 13.8% (35/254) of carriers. Most of the persistent carriers were colonized with methicillin-resistant S. aureus (MRSA) only, and among persistent MRSA carriers, 61.1% (11/18) had indistinguishable genotypes. Of the mothers with MRSA colonization, 77.1% (27/35) had infants who were concomitantly colonized at the age of 1 month; 70.4% (19/27) of the infant-mother paired isolates belonged to indistinguishable or related subtypes, which suggests that surrounding carriers, probably their mothers, may be the possible source for MRSA acquisition in early infancy. CONCLUSIONS Staphylococcus aureus colonization including MRSA was commonly observed in our cohort. Strains of persistent MRSA among infant-mother pairs were usually of indistinguishable genotypes. Therefore, horizontal spread within households is possibly an important factor related to infant MRSA colonization.
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Chin HY, Lin KC, Chiang CH, Wang CJ. Single uroflow study as a tool in predicting the possibility of abnormal voiding symptoms after the administration of antimuscarinic agents in treating overactive bladder syndrome. CLIN EXP OBSTET GYN 2015; 42:152-155. [PMID: 26054108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
PURPOSE OF STUDY The aim of this study was to evaluate the efficacy of uroflowmetry in predicting the possibility of abnormal voiding symptoms following antimuscarinic treatment for overactive bladder syndrome (OAB) in Taiwanese women. MATERIALS AND METHODS A retrospective study was conducted on women with OAB. Forty-five women with abnormal voiding patterns shown by urodynamic study comprised the main group and 38 women with normal voiding patterns comprised the control group. All patients were prescribed two mg tolterodine once daily for one week. Follow-up on complaints of abnormal voiding symptoms was done one week later. RESULTS One woman in control group and 12 women in main group complained of abnormal voiding symptoms. There was a significant difference in the occurrence of abnormal voiding symptoms after antimuscarinic administration between main study group and control group (26.7 % vs 2.6 %, p = 0.02). CONCLUSIOn: Uroflowmetry is a non-invasive and simple tool to predict the occurrence of abnormal voiding symptoms after antimuscarinic use.
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Cheng YH, Deng TC, Chen CC, Chiang CH, Chang CA. First Report of Euphorbia leaf curl virus and Papaya leaf curl Guangdong virus on Passion Fruit in Taiwan. PLANT DISEASE 2014; 98:1746. [PMID: 30703901 DOI: 10.1094/pdis-05-13-0554-pdn] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Passion fruit (Passiflora edulis × Passiflora edulis f. flavicarpa) 'Tainung No. 1' is the main variety cultivated in Taiwan, which is a hybrid and propagated only by grafting. In the spring of 2011, plants with systemic mottle and malformation on leaves were found in some orchards located in Puli and Nantou in central Taiwan. Interestingly, after 3 months of growth, most of these diseased plants became symptomless when the weather became warmer. Nevertheless, some striped concaves were observed on immature fruit surfaces of diseased plants. In March of 2011, two leaf samples exhibiting mosaic and three samples showing malformation were collected and tested by DAS-ELISA; none positively reacted with antibodies against the Cucumber mosaic virus (CMV), East Asian passiflora virus (EAPV), Passion fruit mottle virus (PaMV), or Passion fruit crinkle virus (PCV) that have previously occurred in Taiwan. Rolling-circle amplification (RCA) with hexamer primers were adopted to analyze potential begomoviruses that were prevalent on the other crops in Taiwan (3). The RCA amplified products were digested with BamHI and separated on 1.2% agarose by gel electrophoresis. A fragment, about 3 kb, was purified from each gel and cloned into the respective site of pBluescript SK(-) individually. Clones were screened by EcoRI digestion and two types of restriction fragment length patterns were found among them. One type of a clone containing 2,745 nucleotides (Accession No. KC161185) with 98.5% identity to Euphorbia leaf curl virus (EuLCV) (1) and the other type of a clone containing 2,732 nucleotides (KC161184) with 91.7% identity to Papaya leaf curl Guangdong virus (PaLCuGDV) (2) were revealed by nucleotide comparisons of their DNA-A in GenBank. Accordingly, we confirmed the existence of passiflora isolates of EuLCV and PaLCuGDV. PCR primers CPup/Edw/Pdw (5'TGTGAAGG(A/C/G/T)CC(A/G/T)TGTAA(A/G)GT3'/5'CGCAGTTT CTGGAGGATATTAAG3'/5'TCGCATGCCACTTCCTCAGT3') were designed to differentiate these viruses by amplifying a 235 bp DNA fragment for EuLCV and 345 bp for PaLCuGDV. In a brief survey, all 26 passion fruit leaf samples collected from seven orchards were double infected with EuLCV and PaLCuGDV; only six samples collected from a specific orchard were found to harbor the PaLCuGDV infection. Thirty-seven seedlings from passion fruit (P. edulis f. flavicarpa) seeds were indexed and all were free from both viruses. Five virus-free plantlets of P. edulis f. flavicarpa, one EuLCV and PalCuGDV double infected P. edulis × P. edulis f. flavicarpa, and 20 whiteflies were put into one net tent for 2 months, and then the five plantlets were tested by PCR. The two EuLCV and PalCuGDV specific fragments were amplified from all five plantlets. The two begomoviruses cause mild symptoms on passion fruit plant but the appearance of the fruit was affected. To our knowledge, this is the first report of begomoviruses infecting passion fruit in Taiwan and in Asia. References: (1) X. Ma et al. J. Phytopathol. 152:215. (2) X. Wang et al. Virus Genes 29:303. (3) C. Wu et al. J. Virol. Methods 147:355.
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Lin HY, Chiang CH, Hung WC. STAT3 upregulates miR-92a to inhibit RECK expression and to promote invasiveness of lung cancer cells. Br J Cancer 2013; 109:731-8. [PMID: 23820254 PMCID: PMC3738132 DOI: 10.1038/bjc.2013.349] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2013] [Revised: 06/10/2013] [Accepted: 06/13/2013] [Indexed: 12/19/2022] Open
Abstract
Background: Signal transducer and activator of transcription 3 (STAT3) activation is frequently found in human lung cancer and is associated with increased metastasis and reduced survival. How STAT3 enhances invasiveness is unclear. Methods: The expression of microRNAs and target genes was measured by real-time RT–PCR. Protein level was studied by western blotting. Luciferase reporter assay was used to confirm the direct targeting of microRNAs. Gelatin zymography was used to study matrix metalloproteinase (MMP) activity. Transwell assay was used to investigate cell migration and invasion. Results: Enforced expression of STAT3 decreases the endogenous MMP inhibitor RECK protein but not mRNA level in H460 cells. Conversely, STAT3 inhibitor S3I-201 increases RECK protein in STAT3-activating H1299 cells. We demonstrate that STAT3 upregulates miR-92a to repress RECK via post-transcriptional inhibition. The RECK 3′-untranslated region (3′UTR) reporter activity assay suggests that RECK is a direct repression target of miR-92a. Delivery of pre-miR-92a reduces RECK protein level whereas transfection of anti-miR-92a restores STAT3-induced downregulation of RECK. Anti-miR-92a attenuates MMP activity, migration and invasion of H1299 cells and STAT3-overexpressing H460 cells, suggesting miR-92a is critical for STAT3-induced invasiveness. Conclusion: The STAT3-induced miR-92a promotes cancer invasion by suppressing RECK and targeting of the STAT3/miR-92a axis may be helpful for cancer treatment.
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Liu DG, Chao CH, Chang CH, Juang JM, Liu CY, Chang SH, Chang CF, Chou CK, Tseng CC, Chiang CH, Jean YC, Tang MT, Chung SC, Chang SL. Microbeam MAD Beamline for Challenging Protein Crystallography in TPS. ACTA ACUST UNITED AC 2013. [DOI: 10.1088/1742-6596/425/1/012004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Chou H, Tam MF, Chiang CH, Chou CT, Tai HY, Shen HD. Transaldolases are novel and immunoglobulin E cross-reacting fungal allergens. Clin Exp Allergy 2012; 41:739-49. [PMID: 21488999 DOI: 10.1111/j.1365-2222.2011.03698.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND Mould-induced atopic respiratory diseases are a worldwide problem. Characterization of fungal allergens is of major clinical importance. OBJECTIVE We identified a novel transaldolase family allergen of Cladosporium and Penicillium species. METHODS Fungal allergens were identified by immunoblotting, peptide mass mapping and partial sequencing, cDNA cloning and IgE epitope mapping. RESULTS A 36.5 kDa IgE-binding component in a partially purified C. cladosporioides preparation was identified. Mass spectrometric analyses suggest that this novel IgE-reacting allergen is a transaldolase. A corresponding full-length 1246 bp cDNA encoding a polypeptide of 325 residues was isolated. The newly identified transaldolase allergen has been designated as Cla c 14.0101. The cDNA encoding the Pencillium chrysogenum transaldolase was isolated by RT-PCR according to the cDNA sequence encoding a P. chrysogenum Wisconsin 54-1255 hypothetical protein. The purified rCla c 14.0101 protein reacted with IgE antibodies in 10 (38%) of 26 Cladosporium cladosporioides-sensitized asthmatic patients. Nine of the 10 rCla c 14.0101-positive sera have IgE binding against the recombinant Penicillium transaldolase (rPen ch 35.0101). Among the eight fungal transaldolase-positive sera tested, three showed IgE binding against the recombinant human transaldolase. To determine cross-reactivity between the Cladosporium and Penicillium fungi, IgE cross-reactivity was detected between these two fungal transaldolase allergens by inhibition assays. Both the N- and the C-terminal fragments of Cla c 14.0101 were recognized by IgE antibodies. The C-terminal IgE-reacting determinant was narrowed down to a region encompassing Thr257 to Ser278 of Cla c 14.0101. It was mapped onto a loop-like structure of a 3D model constructed for Cla c 14.0101. CONCLUSION AND CLINICAL RELEVANCE We identified transaldolase as a novel and IgE cross-reactive allergen family of C. cladosporioides and P. chrysogenum. In addition, an IgE-reacting fragment (Thr257 to Ser278) was pinpointed to a loop-like structure on Cla c 14.0101. Results obtained provide important information in clinical mould allergy.
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Chiang CH, Fan YT, Yu TA, Cheng YH, Chen YK. First Report of Passiflora virus Y Infecting Macroptilium atropurpureum in Taiwan. PLANT DISEASE 2012; 96:918. [PMID: 30727392 DOI: 10.1094/pdis-11-11-0952-pdn] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Macroptilium atropurpureum (siratro plants) is a perennial wild legume plant introduced to Taiwan as a forage crop in 1961 (3) and has become a naturalized weed found all over the island. In 2010, siratro plants with virus-like symptoms of mosaic and leaf deformation were observed on the campus of Da-Yeh University in central Taiwan. Flexuous virus-like particles about 750 × 12 nm were observed in the crude sap extracted from symptomatic leaves with a transmission electron microscope. Crude sap was mechanically inoculated to Chenopodium quinoa and local lesions can be observed on inoculated leaves 4 to 5 days after inoculation. Virus was purified from the leaves of inoculated C. quinoa with modified protocols of Gonsalves and Ishii (2). The virus coat protein (CP) consisted of a single major peptide with relative molecular weight of approximately 33 kDa when analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Viral RNA extracted from the purified virus was used as a template and was primed with several primer sets corresponding to potyviruses and carlaviruses in reverse transcription-PCR to amplify possible corresponding cDNA fragments. After several attempts, a cDNA fragment of about 1,300 bp could be amplified with the degenerated primer set of BCMNV-F (5'CCDTGGACDGTWGGVATGAC3') and BCMNV-R (5'CACCAHACCATRAARCCATTCAT3'), which were designed on the basis of the conserved region of the nuclear inclusion b (NIb) and CP genes of some potyviruses including Bean common mosaic necrosis virus, Soybean mosaic virus, Blackeye cowpea mosaic virus, East Asian passiflora virus, and Passion fruit woodiness virus. BLAST analyses showed the amplicon was highly homologous to that of Passiflora virus Y (PaVY). Together with oligo dT, a specific primer (5'GATGACACTCAAATGGCTG3') corresponding to PaVY CP was used to amplify the cDNA fragment of the most 3' region of the viral RNA (about 800 bp). The assembled cDNA fragment of 1,958 bp (Accession No. AB679294) contains a partial NIb gene (877 nt), a complete CP gene (819 nt), and the 3' noncoding region (262 nt). The CP gene shared sequence identities of 89.4 to 98.9% and 92.7 to 98.9% in nucleotide and amino acid, respectively, to that of documented PaVY isolates. PaVY has also been found to be infecting Vigna trilobata, Rhynchosia minima, Clitoria ternatea, and Passiflora foetida in Australia (1). Here we present the first report to our knowledge of PaVY and its infection of siratro (M. atropurpureum) in Taiwan. Additional work is needed to investigate the spread of PaVY and its interaction with other legume plants in Taiwan. References: (1) B. A. Coutts et al. Arch. Virol. 156:1757, 2011. (2) D. Gonsalves and M. Ishii. Phytopathology 70:1028, 1980. (3) Y. Y. Lai et al. J. Taiwan Livestock Res. 42:19, 2009.
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Chiang CH, Yang HI, Jen CL, Lu SN, Wang LY, You SL, Su J, Iloeje UH, Chen CJ. Association between obesity, hypertriglyceridemia and low hepatitis B viral load. Int J Obes (Lond) 2012; 37:410-5. [PMID: 22531094 DOI: 10.1038/ijo.2012.63] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
OBJECTIVE This study aimed to investigate the metabolic risk factors of high hepatitis B viral load. DESIGN Large-scale, community-based cross-sectional study. SUBJECTS A total of 3587 hepatitis B virus (HBV)-infected participants without liver cirrhosis at study entry were investigated. High HBV viral load was defined as a serum level 10(4) copies per ml for hepatitis B e antigen (HBeAg) seronegatives or 10(8) copies per ml for HBeAg seropositives. RESULTS Among HBeAg seropositives (n=545), high HBV viral load was reversely associated with extreme obesity (odds ratio (OR), 0.30; 95% confidence interval (CI), 0.13-0.68; P=0.004) or central obesity (OR, 0.53; 95% CI, 0.34-0.82; P=0.004) after adjustment for gender, hypertriglyceridemia, hyperuricemia and history of hypertension. High HBV viral load remained significantly inversely associated with extreme obesity (OR, 0.17; 95% CI, 0.05-0.63; P=0.008) and central obesity (OR, 0.44; 95% CI, 0.25-0.78; P=0.005) in male HBeAg-seropositive participants in stratification analyses by gender. Among HBeAg seronegatives (n=3042), however, high HBV viral load was inversely associated with hypertriglyceridemia (OR, 0.74; 95% CI, 0.61-0.89, P=0.002) after adjustment for age, gender, high serum alanine aminotransferase level, and extreme obesity or central obesity. High HBV viral load was still inversely associated with hypertriglyceridemia in both female (OR, 0.70; 95% CI, 0.50-0.97; P=0.041) and male (OR, 0.75; 95% CI, 0.60-0.94; P=0.011) HBeAg-seronegative participants. CONCLUSION Extreme obesity and central obesity were associated with a low prevalence of high HBV viral load in HBeAg seropositives, especially in men; while hypertriglyceridemia was associated with a low prevalence of high viral load in HBeAg seronegatives in both women and men.
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Chin HY, Lin KC, Chiang CH, Wang CJ. Combination of baclofen and antimuscarinics to reduce voiding difficulty in treating women with overactive bladders. CLIN EXP OBSTET GYN 2012; 39:171-174. [PMID: 22905457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
PURPOSE OF STUDY To evaluate the efficacy of baclofen in combination with antimuscarinics to treat women with an overactive bladder (OAB) with abnormal voiding patterns. METHODS An action research and chart review was conducted in 245 OAB women. Women were prescribed tolterodine or oxybutynin with or without baclofen after urodynamics. The complaint of voiding difficulty was followed up one week later. RESULTS There was a significant difference in the occurrence of voiding difficulty after antimuscarinic administration in OAB women with abnormal voiding patterns compared with normal patterns (18% vs 4.9%, respectively; p = 0.013). The clinical difference of voiding difficulty after treating with antimuscarinics between both voiding patterns disappeared after adding baclofen (abnormal voiding pattern vs normal pattern; 11.1% vs. 5.6%, respectively; p = 1.000). CONCLUSION Combined use of baclofen and antimuscarinic agents could reduce voiding difficulty in treating women with overactive bladders with abnormal voiding patterns.
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Cheng YH, Deng TC, Chen CC, Liao JY, Chang CA, Chiang CH. First Report of Pepper mottle virus in Bell Pepper in Taiwan. PLANT DISEASE 2011; 95:617. [PMID: 30731963 DOI: 10.1094/pdis-10-10-0721] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Bell pepper (Capsicum annuum L.) plants exhibiting systemic mild mosaic, vein yellowing, and leaf malformation were collected from Puli City in 2006. Double-antibody sandwich (DAS)-ELISA was used to test these samples for Chilli veinal mottle virus (ChiVMV) infection using polyclonal antibodies. In addition, Chenopodium quinoa, C. amaranticolor, and Nicotiana benthamiana plants were mechanically inoculated with sap extracted from collected samples. Ten days postinoculation, chlorotic local lesions were observed on inoculated leaves of C. quinoa and C. amaranticolor plants, whereas, systemic mosaic and foliar distortion symptoms were developed on upper leaves of N. benthamiana plants. The DAS-ELISA test showed that field-collected pepper samples and inoculated leaves of C. quinoa and C. amaranticolor were infected with ChiVMV, while N. benthamiana with mosaic symptoms did not react with ChiVMV antibodies. To confirm ChiVMV, field-collected samples as well as mechanically inoculated plants were tested by reverse transcription (RT)-PCR using the potyvirus degenerate primers Hrp5/Pot1 (2). Amplified RT-PCR products were cloned and sequenced. Sequence analysis of amplified fragments (1.4 kb) revealed that field-collected pepper samples were infected with ChiVMV and Pepper mottle virus (PepMoV). The DNA fragment amplified from C. quinoa and C. amaranticolor showed high (99.2%) sequence identities with the CP gene of ChiVMV (3) (GenBank Accession No. AM909717). However, amplicons obtained from N. benthamiana plants (GenBank Accession No. HQ329082) that showed mosaic symptoms showed 83.6% to 98.7% nucleotide identities with PepMoV (GenBank Accession Nos. AB126033, AF227728, AF440801, AF501591, EU586133, and M96425). Next, a pure isolate of PepMoV was established on N. benthamiana by mechanical inoculation of diluted plant sap obtained from a PepMoV-infected N. benthamiana plant. Bell pepper plants inoculated with the Taiwan isolate of PepMoV developed mosaic and leaf distortion symptoms. Antiserum against the PepMoV Taiwan isolate was subsequently prepared by immunizing rabbits with purified virus particles. Using the prepared antiserum and specific primers (1) to detect PepMoV, ChiVMV, and Pepper veinal mottle virus (PVMV), three viruses could be readily detected and differentiated from diseased bell peppers in the field. In a survey done in 2007, 18 of 33 pepper samples from southern Taiwan were found with mixed infections of PepMoV and ChiVMV, seven samples were infected with PepMoV and PVMV, five samples were infected with PVMV, and another three samples were infected with ChiVMV. To our knowledge, this is the first report of the occurrence of PepMoV in bell peppers in Taiwan. References: (1) Y. H. Cheng et al. Plant Dis. 93:107, 2009. (2) S. S. Pappu et al. Plant Dis. 82:1121, 1998. (3) W. S. Tsai et al. Plant Pathol. 58:408, 2008.
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Yeh MK, Chen JL, Chiang CH. In vivoandin vitrocharacteristics for insulin-loaded PLA microparticles prepared by w/o/w solvent evaporation method with electrolytes in the continuous phase. J Microencapsul 2008; 21:719-28. [PMID: 15799222 DOI: 10.1080/02652040400008481] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Insulin-loaded poly(lactide) (PLA) microparticles were successfully prepared by 6% w/v PLA in the organic phase, 10% w/v PVP and varied types of 5%w/v electrolytes in the continuous phase, by using a water-in-oil-in-water emulsion/ solvent extraction technique. Addition of electrolytes such as NaCl, CaCl2 into the external phase significantly improved insulin entrapment efficiency compared to the case of no additives. NaCl was the most effective for obtaining high entrapment efficiency, with microparticle yield 81.2%, trapping efficiencies 49%, insulin-loading level 5.5% w/w and mean particle size 14.8 microm. The distribution (%) of insulin on the PLA microparticles surface, outer layer and core were 8, 37 and 43%, respectively. The cumulative release of insulin had an upper limit of approximately 24% of the insulin load at 24 days. A steady release rate was 0.5 microg insulin/mg microparticles/day of insulin release maintained for 24 days. Total protein-leaking amount was reduced after addition of electrolytes in the continuous aqueous phase. Rabbit glucose levels were evaluated after subcutaneous 20 mg insulin-loaded PLA microparticles or PLA blank microparticles. Study results show that the insulin-loaded PLA microparticles significantly reduced the glucose level than PLA blank microparticles. The insulin-loaded PLA microparticles, physicochemical characterization data and the animal result obtained in this study may be relevant in optimizing the PLA microparticle formulation incorporation and delivery insulin carriers.
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Chen JL, Yeh MK, Chiang CH. The mechanism of surface-indented protein-loaded PLGA microparticle formation: the effects of salt (NaCl) on the solidification process. J Microencapsul 2008; 21:877-88. [PMID: 15799543 DOI: 10.1080/02652040400015387] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The purpose of this study was to evaluate ovalbumin (OVA) leakage pathways and to explore the mechanism of the surface-indented microparticle formation in the preparation of OVA-loaded microparticles. OVA-loaded poly (D,L-lactic-co-glycolic acid) (PLGA) microparticles were prepared by a water-in oil-in water (w/o/w) solvent evaporation method associated with varied NaCl (NaCl) concentrations and adjusted with urea at 1240mOsm kg(-1) in the external aqueous phase. To evaluate dichloromethane (DCM)-related OVA leakage, three stirring rates, 600, 800, 1000rpm at 25 degrees C were carried out during the solvent evaporation stage. Both DCM and OVA levels in the external phase medium and total dispersion were sampled and measured. The time course of particle characteristics was evaluated by microscopy or SEM photography. The surface adsorptive capacities of the prepared microparticles were measured by using bovine serum albumin conjugated with fluorescein isothiocyanate (FITC-BSA). The findings were that the DCM-related OVA leakage accounted for approximately 34%, of the total leakage. By combining NaCl in the external phase, a faster solidifying crust-like structure was formed as a barrier to remarkably reduce OVA loss and improve OVA content from 40.1 to 72.8 microg mg(-1). The yield and OVA content for formulations containing NaCl were much improved by the ionic effect, in addition to the osmotic effect. The total entrapment efficiency was also highly increased from 43 to 72%. The formations of the crust-like surface structure of the microparticle were affected by entrapped drugs, salt content in the external phase and aqueous volume in the inner phase. A scheme was proposed to interpret the formation mechanism of the surface-indented microparticles. In comparison to the surface-smooth microparticles, the surface adsorptive capacities of the surface-indented microparticles were highly improved from 26.6 to 87.0%, determined by the adsorption of FITC-BSA.
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Chao CL, Hung CS, Lin YH, Lin MS, Lin LC, Ho YL, Liu CP, Chiang CH, Kao HL. Time-dependent benefit of initial thrombosuction on myocardial reperfusion in primary percutaneous coronary intervention. Int J Clin Pract 2008; 62:555-61. [PMID: 18067561 DOI: 10.1111/j.1742-1241.2007.01542.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND In ST-segment elevation acute myocardial infarction (STEMI), dislodgement of thrombus within the culprit artery during primary percutaneous coronary intervention (PCI) may cause distal embolisation and impaired myocardial reperfusion. Clinical results of thromboembolic protection strategies have been controversial. We conducted this study to investigate whether the benefit of thrombus removal is time dependent. METHODS Seventy-four STEMI patients within 12 h from onset were randomised to receive either primary PCI with initial thrombosuction (IT) or standard strategy. Results were analysed in subgroups according to the onset-to-lab time intervals (subgroup 1: 0-240 min, subgroup 2: 241-480 min and subgroup 3: 481-720 min). RESULTS The primary end-points were improvements in thrombolysis in myocardial infarction flow (DeltaTIMI) and myocardial blush grade (DeltaMBG) postprocedure. Better DeltaTIMI (2.2 +/- 1.1 vs. 1.5 +/- 1.3, p = 0.014) and DeltaMBG (2.3 +/- 1.1 vs. 1.0 +/- 1.5, p < 0.001) were observed in IT patients, compared with standard PCI patients. In onset-to-lab time subgroup analysis, the difference between IT and standard PCI is significant only in subgroup 2 (DeltaTIMI 2.6 +/- 1.0 vs. 1.3 +/- 1.2, p = 0.007; DeltaMBG 2.6 +/- 0.9 vs. 1.0 +/- 1.1, p = 0.010), but not in the other two subgroups. CONCLUSIONS This prospective randomised study shows that primary PCI with IT may improve epicardial flow and myocardial reperfusion in patients with STEMI, and this benefit is the most significant in patients treated within 4-8 h after symptom onset.
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Fu SH, Chen YT, Chiang CH, Hsu BRS. Enhancing engraftment of neonatal porcine xenoislet with CTLA4Ig and nordihydroguaiaretic acid. Transplant Proc 2007; 38:3283-5. [PMID: 17175250 DOI: 10.1016/j.transproceed.2006.10.089] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2006] [Indexed: 11/24/2022]
Abstract
This study examined the combinatory effect on graft survival of neonatal pig pancreatic cell clusters (NPCC) with nordihydroguaiaretic acid (NDGA), a 5-lipoxygenase inhibitor, with systemic CTLA4Ig expression, with local CTLA4Ig and with interleukin-1 (IL-1) receptor antagonist (IL-1ra) expression using a pig to mouse model. About 2000 NPCCs, which were infected with both adenoviruses carrying CTLA4Ig and IL1-1ra genes (each 500 pfu/NPCC), were transplanted beneath the kidney capsule of diabetic BALB/c mice. Two days before transplantation, the recipient mice were either injected with (group C, n = 4; group D, n = 6) or without (group A, n = 7; group B, n = 9) 1 x 10(13) pfu/kg body weight of adenovirus carrying the CTLA4Ig gene. Mice in groups B and D received daily injections of NDGA (20 mg/kg body weight) subcutaneously for 4 weeks. Blood glucose levels less than 200 mg/dL were defined to be normoglycemic and the transplant termed as a functioning graft for the purpose of calculating mean graft function time (MFT). Four weeks posttransplantation, an intraperitoneal glucose tolerance test (IPGTT) was performed to calculate the area under the curve (AUC). Blood glucose levels in groups C and D were significantly lower than groups A and B at 1, 2, and 3 weeks after transplantation. Graft MFT and AUC of IPGTT in group D were significantly different from those in groups A and B. Our data suggested that a high dosage of systemic expression of CTLA4Ig was effective to enhance xenograft survival and that in it was reinforced by a combination with the macrophage inhibitor NDGA.
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Huang YC, Vieira A, Huang KL, Yeh MK, Chiang CH. Pulmonary inflammation caused by chitosan microparticles. J Biomed Mater Res A 2005; 75:283-7. [PMID: 16059899 DOI: 10.1002/jbm.a.30421] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Chitosan is a cationic biopolymer derived from chitin with potential therapeutic applications such as controlled drug delivery to mucosal-epithelial surfaces in the body. Inhaled chitosan microparticles (CM), for example, are of potential interest in pulmonary pharmacotherapy. In this context, we examine some basic reactions of lung tissue to CM. Inhaled CM (2-10 mg/kg of particles) induce dose-dependent proinflammatory effects in rat lungs; these effects are documented in increases in bronchoalveolar lavage fluid protein (BALF-P) and lactate dehydrogenase activity (BALF-LDH) and increases in lung tissue myeloperoxidase (MPO) activity and leukocyte migration. Overall, the biochemical parameters (i.e., average of BALF-P, BALF-DH, and MPO) indicate that the inflammation response is 1.8-fold greater than controls without CM; the same inflammation parameters, however, are 1.9-fold lower with CM compared with the proinflammatory effects of lipopolysaccharide (LPS). Cytological examination of BALF shows a large infiltration of polymorphonuclear neutrophils to lung tissue: more than a sixfold increase in this population of inflammatory cells, after inhalation of CM relative to air inhalation controls. Thus, the results indicate that inhaled CM can have significant proinflammatory effects on lung tissues; these effects are mild relative to LPS but need to be considered in the context of therapeutic applications via pulmonary delivery if such concentrations of CM are used.
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Hsu JJ, Chiang CH, Hsieh CC, Hsieh TT. The influence of image magnification in first-trimester screening for Down syndrome by fetal nuchal translucency in Asians. Prenat Diagn 2004; 24:1007-12. [PMID: 15614833 DOI: 10.1002/pd.810] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE The aim of this prospective study was to evaluate the impact of image magnification in the measurements of crown-rump length (CRL) and nuchal translucency (NT) thickness for first-trimester Down syndrome screening in Asians. METHODS Ultrasound measurements of NT and CRL were performed in 561 consecutive Taiwanese unaffected fetuses and 11 cases of Down syndrome fetuses between 12 and 14 weeks of gestation. All sonographic images were measured by one qualified examiner to prospectively undergo first-trimester NT screening for Down syndrome. Fetal CRL and NT thickness were measured on three separated images including the original image, regular image, and the magnified image. RESULTS A significant mean difference (0.59 +/- 4.24 mm) of CRL was found between measurements on the original and regular image (p < 0.001). There was a significant mean difference of NT thickness measurements between the regular and magnified image (0.12 +/- 0.25 mm, p < 0.001). Seven out of the 11 cases (63.6%) of Down syndrome with NT thickness > or =2.5 mm was measured on three separated images. A significantly reduced incidence of NT thickness > or =2.5 mm on the magnified image was noted than those of the original and regular image measurements in unaffected cases (p < 0.001). Either using the assessing method by the 95th centile cutoff value of NT thickness or combined risk, our results could achieve observed detection rate of 63.6% measured on three separated images. CONCLUSIONS Our data indicate that the image magnification could reduce the false-positive rate by using a fixed cutoff value of NT thickness, but would have no influence on the results when using the assessing method either by the 95th centile cutoff value of NT thickness or the combined risk. In order to place the caliper more accurately, a magnified image should be recommended as a standard image in the measurements of the NT thickness.
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Huang YC, Yeh MK, Cheng SN, Chiang CH. The characteristics of betamethasone-loaded chitosan microparticles by spray-drying method. J Microencapsul 2003; 20:459-72. [PMID: 12851046 DOI: 10.1080/0265204021000058456] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Betamethasone (BTM)-loaded microparticles prepared by a spray drying method using chitosan (CTS) as raw material, type-A gelatin and ethylene oxide-propylene oxide block copolymer (Pluronic F68) as modifiers. The BTM-loaded in varied chitosan/Pluronic F68/gelatin microparticle formulations was investigated. By properly choosing excipient type and concentration a high degree of control was achieved over the physical properties of the BTM-loaded microparticles. Microparticle characteristics (zeta potential, tap density, particle size and yield), loading efficiencies, microparticle morphology and in-vitro release properties were examined. Surface morphological characteristics and surface charges of prepared microparticles were observed by using scanning electron microscopy (SEM) and microelectrophoresis. A SEM micrograph shows that the particle sizes of the varied chitosan composed microparticles ranged from 1.1-4.7 microm and the external surfaces appear smooth. The BTM-loaded microparticles entrapped in the chitosan/Pluronic F68/gelatin microparticles with trapping efficiencies up to 93%, collected yield rate 44%, and mean particle size varied between 1-3 microm, positive surface charge (20-40 mv), and tap densities (0.04-0.40 g/cm3) were obtained. The collected BTM yield and size of particle was increased with increasing BTM-loaded amount but both zeta potential and tap density of the particles decreased with increasing BTM-loaded amount. The in vitro release of BTM showed a dose-dependent burst followed by a slower release phase that was proportional to the drug concentration in the concentration range between 5-30%w/w. The in vitro drug release from the chitosan/Pluronic F68/gelatin 1/0.1/0.4 microspheres had a prolong release pattern. These formulation factors were correlated to particulate characteristics for optimizing BTM microspheres in pulmonary delivery.
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Huang YC, Chiang CH, Yeh MK. Optimizing formulation factors in preparing chitosan microparticles by spray-drying method. J Microencapsul 2003; 20:247-60. [PMID: 12554378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
The chitosan only, chitosan/Pluronic F68, chitosan/gelatin, chitosan/Pluronic F68/gelatin microparticles and betamethasone-loaded chitosan/Pluronic F68/gelatin microparticles were successfully prepared by a spray-drying method. Microparticle characteristics (yield rate, zeta potential, particle size and tap density), loading efficiencies, microparticle morphology and in-vitro release properties were investigated. By properly choosing excipient type, concentration and varying the spray-drying parameters, a high degree of control was achieved over the physical properties of the dry chitosan powders. SEM micrograph shows that the particle sizes of the varied chitosan composed microparticles ranged from 2.12-5.67 microm and the external surfaces appear smooth. Using betamethasone as model drug, the spray-drying is a promising way to produce good spherical and smooth surface microparticles with a narrow particle size range for controlled delivery of betamethasone. The positively charged betamethasone-loaded microparticles entrapped in the chitosan/Pluronic F68/gelatin microparticles with trapping efficiencies up to 94.5%, yield rate 42.5% and mean particle size 5.64 microm varied between 4.32-6.20 microm and tap densities 0.128 g/cm(3). The pH of particle was increased with increasing betamethasone-loaded amount, but both zeta potential and tap density of the particles decreased with increasing betamethasone-loaded amount. The betamethasone release rates from chitosan/Pluronic F68/gelatin microparticles were influenced by the drug/polymer ratio in the manner that an increase in the release% and burst release% was observed when the drug loading was decreased. The in vitro release of betamethasone showed a dose-dependent burst followed by a slower release phase that was proportional to the drug concentration in the concentration range between 14-44%w/w.
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Yeh MK, Coombes AGA, Chen JL, Chiang CH. Japanese encephalitis virus vaccine formulations using PLA lamellar and PLG microparticles. J Microencapsul 2002; 19:671-82. [PMID: 12433308 DOI: 10.1080/02652040210142551] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Japanese encephalitis virus (JEV)-loaded poly(lactide) (PLA) lamellar and poly(DL-lactide-co-glycolide) (PLG) microparticles were successfully prepared with low molecular weight PLA by the precipitate method and with 6% w/v PLG in the organic phase, 10% w/v PVP and 5% w/v NaCl in the continuous phase, by using a water-in-oil-in-water emulsion/solvent extraction technique, respectively. JEV was entrapped in the PLG microparticles by a solvent extraction technique with trapping efficiencies up to 98%, loading level 5.5% w/w, and mean particle size 3.8 microm. The distribution (%) of JEV on the PLG microparticles surface, outer layer, and core were 11.2, 41.7 and 46.4%, respectively. The cumulative release of JEV had an upper limit of approximately 58% of the JEV load at 24 days. The steady release rate was 1.33 microg JEV/mg microparticles/day of JEV release maintained for 24 days. The corresponding virus loading of the PLA lamellae is approximately 0.78% w/w and the loading efficiency (77.8%), JEV content (7.84 microg/mg), and yield (96.3%), respectively. The distribution (%) of JEV on the microparticles surface, outer layer, and core were 82.1, 13.3 and 2.2%, respectively. The live JEV challenge in mice test, in which mice received one dose of 20 mg JEV-loaded PLG microparticles, 20 mg JEV-loaded PLA lamellar in comparison with JEV or PBS solution, was evaluated after IP immunization of BALB/c mice. The study results show that the greatest survival was observed in the group of mice immunized with 20 mg JEV-loaded PLG microparticles and 20 mg JEV-loaded PLA microparticles group (80%). The JEV incorporation, physicochemical characterization data, and the animal results obtained in this study may be relevant in optimizing the vaccine incorporation and delivery properties of these potential vaccine targeting carriers.
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Chen JL, Chiang CH, Yeh MK. The mechanism of PLA microparticle formation by water-in-oil-in-water solvent evaporation method. J Microencapsul 2002; 19:333-46. [PMID: 12022499 DOI: 10.1080/02652040110105373] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Microparticles containing ovalbumin as a model protein drug were prepared using poly(L-lactide; PLA) with a water-in-oil-in-water emulsion/solvent evaporation technique. The dispersed phase was PLA dissolved in dichloromethane (DCM), and the continuous phase was water-containing polyvinyl pyrolidone (PVP) as stabilizer with sodium chloride. Microparticle characteristics, loading efficiencies, protein distribution in microparticles, and in-vitro release properties were investigated. The OVA leaking into the continuous phase during the formation of microparticle by DCM evaporation was also evaluated. Results show that OVA was successfully entrapped in the microparticles with trapping efficiencies up to 72%, loading level 8.7% w/v, and particle size 14 microm. The semi-solid suspension changes to a solid particle happened during a 10-min period. Total protein-leaking amount was reduced after addition of NaCl in the continuous aqueous phase, which resulted from reducing the solidification time and protein-leaking rate. Using 5% w/v NaCl in the continuous phase resulted in higher loading content (87.2 +/- 1.0 microg/mg), and loading efficiency (72.2%), which resulted from more protein in the deeper layer (50.2 +/- 2.3 microg/mg) and higher microparticle yield (75.2%) than without NaCl (loading content: 74.0 +/- 1.0 microg/mg; loading efficiency 51.8%; deeper layer content: 18.3 +/- 3.5 microg/mg; yield: 63.6%). These results constitute a step forward in the improvement of existing technology in controlling protein encapsulation and delivery from microparticles prepared by the multiple emulsion solvent evaporation method.
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Yeht MK, Chen JL, Chiang CH. Vibrio cholerae-loaded poly(DL lactide co-glycolide) microparticles. J Microencapsul 2002; 19:203-12. [PMID: 11837975 DOI: 10.1080/02652040110081334] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Vibrio cholerae (VC)-loaded microparticles were prepared using poly(DL lactide-co-glycolide) with a water-in-oil-in-water emulsion/solvent extraction technique. Particle characteristics including size distribution, VC-loading efficiencies, and in-vitro release pattern were investigated. The dispersed phase was PLG dissolved in dichloromethane, and the continuous phase was water containing PVP as a stabilizer with varied sodium chloride concentrations. VC was successfully entrapped in the microparticles with trapping efficiencies up to 97.8%, a loading level of 55.4 g/mg, and particle size of 3.8 microm. Using 10% w/v PVP with 5% w/v NaCl in the continuous phase resulted in a higher loading level (55.4 +/- 6.9 g/mg), loading efficiency (97.8%), core region content (25.7 +/- 1.9 g/mg) and lower surface content (6.2 +/- 0.9 g/mg) than without NaCl (loading content: 40.7 +/- 5.1 g/mg; loading efficiency 52.1%; core region content: 8.3 +/- 0.5 g/mg; surface content: 19.5 +/- 1.1 g/mg). A linear release profile from VC-loaded microparticles was found. A preliminary animal oral administration study indicated that the VC-loaded microparticles, as an oral delivery system, have shown effective immunogencity in rats for 2 months. The VC incorporation and physicochemical characterization data obtained in this study may be relevant in optimising the vaccine incorporation and delivery properties of these potential vaccine targeting carriers.
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Chiang CH, Tung SM, Lu DW, Yeh MK. In vitro and in vivo evaluation of an ocular delivery system of 5-fluorouracil microspheres. J Ocul Pharmacol Ther 2001; 17:545-53. [PMID: 11777178 DOI: 10.1089/10807680152729239] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Solvent evaporation technique with O/O (oil/oil) emulsion was used to prepare 5-FU (5-fluorouracil) biodegradable microspheres with a polymer of poly(dl-lactide-co-glycolide) combining lecithin as an emulsifier. In vitro drug release was conducted in phosphate buffer with pH 7.4 at 37 degrees C. For in vivo studies, 10 mg of 5-FU microspheres (containing 1 mg of 5-FU) were implanted in the conjunctival area of the rabbit eye. Rabbits were sacrificed at certain time intervals within 7 days after drug application. Samples of aqueous humor and sclera were prepared and analyzed by the high performance liquid chromatography (HPLC) method. The tested 5-FU microsphere contained 10% drug with a mean particle size of 4.4 +/- 0.6 microm. The microsphere had a burst release initially (64.9 +/- 1.5%), followed by a sustained release; the cumulative release at time points of 1, 10 and 21 days were 71.9 +/- 1.9%, 80.1 +/- 2.1% and 89.8 +/- 2.3%, respectively. For in vivo studies, aqueous humor levels showed a peak at the first sampling point (2 hr), then maintained low levels of 5-FU with a range 0.2-1 microg/mL. Scleral levels were 20-80 microg/mL during a 7-day study. Our results indicate that the prepared 5-FU microsphere provided a long-term release for more than 1 week. The preparation showed no irritation and low toxicity (< 100 microg/mL). For application to the eye, it might be potentially useful as a complement drug system in glaucoma filtration surgery.
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Chiang CH, Yu CP, Wu CP, Yan HC, Perng WC. Cytokine up-regulation in ischaemic/reperfused lungs perfused with University of Wisconsin solution and normal saline. Clin Sci (Lond) 2001; 101:285-94. [PMID: 11524046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Ischaemia/reperfusion (I/R) lung injury using University of Wisconsin solution (UW) as perfusate has not been well studied. Isolated rat lungs were challenged with various periods of ischaemia and/or reperfusion. Haemodynamics, lung weight gain (LWG), capillary filtration coefficient (K(fc)), tissue pathology, the concentrations of cytokines in the perfusate, and mRNAs for the various cytokines in the lung tissues were measured. I/R induced a permeability type of pulmonary oedema, as reflected by increases in LWG and K(fc). LWG and K(fc) in the I(45)R(60)(UW) group (45 min of ischaemia followed by 60 min of reperfusion with UW) were only 2% and 5% respectively of those in the I(45)R(60)(NS) group (where NS is normal saline). LWG and K(fc) in the UW group had both increased by 180 min, to values similar to those in the I(45)R(60)(NS) group. However, these findings show that UW was remarkably effective at preventing LWG after 60 min of reperfusion, and was more than 3-fold more effective than NS in delaying LWG. For longer ischaemic times only, or the same period of ischaemia followed by longer reperfusion periods, greater lung injury occurred. I/R lung injury also induced increased concentrations of tumour necrosis factor-alpha (TNF-alpha), interleukin 1 and interleukin 6 in the perfusate, and increased the mRNAs for these cytokines in lung tissue. A significant correlation was obtained between TNF-alpha concentration and LWG. TNF-alpha production in the I(45)R(60)(UW) group was only 7% of that in the I(45)R(60)(NS) group. However, TNF-alpha mRNA expression in the I(45)R(60)(UW) group was 80% of that in the I(45)R(60)(NS) group. This indicates that transcription/translation do not correlate well with cytokine production, and also suggests that one reason for the effectiveness of UW in delaying LWG may be because it delays TNF-alpha production. In summary, ischaemia or I/R caused a permeability-type pulmonary oedema that was associated with leucocyte infiltration and the up-regulation of various cytokines, regardless of the perfusion fluid. Except for pulmonary hypertension, less severe I/R lung injury and delayed cytokine production in lungs perfused with UW, the pattern of injury associated with I/R challenge was similar to that in lungs perfused with NS. We propose that more or long-acting protective agents are required as additives in order to modify UW to produce an optimal preservation solution.
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