PubMed Health⌕ Search

Biomedical subjects

Hsi-Hsun Lin

Publications and source records attributed to Hsi-Hsun Lin.

At least 19 recordsLinked to original sources
PubMed2006

Performance characteristics of the limulus amebocyte lysate assay and gas chromatography-mass spectrum analysis of lipopolysaccharides relative to nitric oxide production by peritoneal exudates of cells.

Limulus amebocyte lysate (LAL) assay and gas chromatography-mass spectrum (GC-MS) analysis are usually used for the quantification of lipopolysaccharides (LPS) from the environment. The LAL assay measures endotoxin units to represent the LPS biological function but GC-MS analysis measures decanoic (C(10:0)) and dodecanoic (C(12:0)) 3-hydorxy fatty acids (3-OH FA) concentration to represent the LPS chemical composition. A study was carried out using these methods to evaluate their degree of correlation. Using the culture supernatants of 30 independent strains of Pseudomonas aeruginosa, the bacterial supernatants gave of 0.53+/-0.45 and 2.49+/-1.75mg/l of C(10:0) and C(12:0) 3-OH FA, respectively, compared to 17.96+/-13.28mg/l of LPS with the LAL assay (1ng/ml of LPS congruent with0.78EU/ml). The 3-OH FA concentration relative to the endotoxin unit dose in the supernatants exhibited a positive correlation (r(2)=0.5182, C(10:0); r(2)=0.4359, C(12:0)). When supernatants having a high level of endotoxin were used to treat peritoneal exudates cells, nitric oxide (NO) was generated in a dose-dependent manner (r(2)=0.6174). To determine if either C(10:0) or C(12:0) 3-OH FA can act as an indictor of LPS quantity was correlated with this immunostimulatory effect, the correlation of these 3-OH FA concentrations against the produced NO levels was evaluated. This also exhibited a positive correlation; however, the two indicators of 3-OH FA gave different dose-responsible performances (r(2)=0.3211, C(10:0); r(2)=0.4527, C(12:0)).

Animals↗
PubMed2006

Presence of the exoU gene of Pseudomonas aeruginosa is correlated with cytotoxicity in MDCK cells but not with colonization in BALB/c mice.

A total of 141 independent strains of Pseudomonas aeruginosa with different heterogeneities in the exo gene (exoS, exoT, exoU, and exoY) background were examined for their pathogenic roles. Results indicated that the exoU gene is the major contributor to cytotoxicity in Madin-Darby canine kidney cells but is not related to bacterial colonization in mice.

Animals↗
PubMed2006

Genetic characterization of diverse HIV-1 strains in an immigrant population living in New York City.

New York City (NYC) is one of the original foci of the HIV-1 epidemic and has a greater number of AIDS cases than any other city in the United States. NYC also hosts the highest number of immigrants among the nation's cities: more than 2 million among a total population of 8 million. Such a high rate of immigration could act as a potential source for introducing and disseminating novel HIV-1 strains into the United States. Our current study focuses on the genetic characterization of HIV-1 strains circulating in an immigrant population in NYC. Of the 505 HIV-1-positive specimens obtained, 196 were available for viral sequencing from the C2 to V3 region of env. Phylogenetic analysis using maximum-likelihood and neighbor-joining methods demonstrated that non-B subtypes and circulating recombinant forms (CRFs) accounted for 43.4% (85 of 196 cases), whereas the remaining 56.6% (111 of 196) cases had viral variants similar to the typical North American subtype B virus. Of those non-B subtypes and CRFs, subtype A and CRF02 dominated (63.5% combined); other subtypes, including C, D, F1, G, CRF01_AE, and CRF06_cpx, were also detected. Two HIV-1 sequences do not cluster with any known subtypes or CRFs. Furthermore, the distribution of non-B subtypes and CRFs was consistent with the countries of origin, suggesting that many of the study subjects were likely infected in their home country before they entered the United States. Subtype B viruses identified in the immigrant population showed no significant differences from the typical North American B subtype, however, indicating that a significant proportion of the immigrants must have been infected after they came to the United States. Public health officials and physicians should be aware of the growing genetic diversity of HIV-1 in this country, particularly in areas with sizable immigrant populations.

Adolescent↗
PubMed2006

Acute acalculous cholecystitis: A rare presentation of typhoid fever in adults.

Adult typhoidal acute acalculous cholecystitis is rare with only 2 cases having been reported in the English literature. We present the case of a previously healthy 36-y-old female who suffered fever, chills, epigastralgia and progressive jaundice for 3 d, with acute acalculous cholecystitis subsequently diagnosed. In addition to antibiotic therapy with ceftriaxone, open cholecystectomy was performed. However, bile and blood culture both showed Salmonella typhi growth unexpectedly, and ileocolitis was revealed by colonoscopy. Careful tracing of the history of the patient recalled a history of travel to Indonesia. In adults without common risk factors for acalculous cholecystitis, a detailed history including travel to endemic areas and high index of suspicion for typhoidal acute acalculous cholecystitis are important, and appropriate antimicrobial therapy for covering Salmonella typhi should be considered.

Acute Disease↗
PubMed2006

An epidemic of HIV type I CRF07_BC infection among injection drug users in Taiwan.

The human immunodeficiency virus type 1 (HIV-1) epidemic in Taiwan is rapidly escalating because of an increasing number of injection drug users (IDUs). A molecular epidemiological study of HIV-1-infected IDUs in Taiwan was conducted from January 2004 to April 2005. Of the 131 HIV-1-positive specimens collected, all contained detectable sequences, including 105 from the C2-V3 region of env and 87 from the protease and reverse transcriptase genes of pol. Phylogenetic analysis of these sequences indicated that 128 individuals harbored CRF07_BC, which resembles the dominant strains circulating among IDUs in China. Twenty-three individuals had a history of travel to the southwest provinces of China and shared needles or apparatuses there. This suggests that CRF07_BC might have been transmitted from China into Taiwan, thereby causing an outbreak among IDUs in Taiwan. This is the first report in the English literature of the appearance of HIV-1 CRF07_BC in Taiwan. These provide information relevant to the development of antiviral therapy and vaccine in Taiwan and may assist public health workers in the prevention of HIV-1 spread.

Adult↗
PubMed2006

CpG-modified plasmid DNA encoding flagellin improves immunogenicity and provides protection against Burkholderia pseudomallei infection in BALB/c mice.

The plasmid DNA encoding the fliC gene of Burkholderia pseudomallei combined with CpG oligodeoxynucleotide (ODN) was injected intramuscularly into BALB/c mice, resulting in the increased production of certain humoral antibodies and flagellin-specific spleen cell clonal expansion. CpG ODN, as an immunoadjuvant, was added to the plasmid containing the fliC gene in order to obtain ongoing expression in muscle for a long period. Functional expression of flagellin from the constructed CpG-modified plasmid in transfected peritoneal exudate cells of BALB/c mice was shown by reverse transcription-PCR and Western blotting. Furthermore, BALB/c mice immunized with the modified plasmid had relatively higher resistance to B. pseudomallei infection in vivo than did mice immunized with unmodified plasmid DNA. The time course of restricted bacterial growth in spleen and liver and changes in the cytokine profiles of immunized mice suggested that the stimulated phagocytic cells would be able to kill the bacteria eventually, possibly as a consequence of the induction of Th-1-type immune polarization in vivo. Th-1-type immune polarization was detected in response to flagellin induction in mice immunized with CpG-modified plasmid DNA by the appearance of increased levels of immunoglobulin G2a antibodies and gamma interferon-secreting cells specific to flagellin. The exogenous CpG motifs added to the fliC gene would contribute to an adjuvant-like response that enhances the flagellin-specific immunogenicity and provides protection against B. pseudomallei infection. This CpG-modified plasmid DNA vaccination is an important potential strategy that should be developed to protect against melioidosis.

Adjuvants, Immunologic↗
PubMed2006

Opportunistic infections in adults with acquired immunodeficiency syndrome: a comparison of clinical and autopsy findings.

BACKGROUND AND PURPOSE: Many opportunistic infections causing death in acquired immunodeficiency syndrome (AIDS) patients are often not diagnosed prior to death. The objective of this study was to compare the premortem and postmortem diagnoses of opportunistic infections and tumors among 15 AIDS patients treated in a hospital in southern Taiwan. METHODS: Total autopsy (brain, chest and abdominal cavity) was performed in 2 patients, and partial autopsy in 13. RESULTS: Pneumocystis carinii pneumonia, candidiasis, lymphoma, Kaposi's sarcoma, toxoplasmosis and salmonellosis were more commonly diagnosed before death than at autopsy. By contrast, cytomegalovirus (CMV) infections and herpes simplex virus or varicella-zoster virus infections were more frequently diagnosed at postmortem examinations than prior to death. CONCLUSIONS: In conclusion, this study found substantial discrepancies between autopsy findings and premortem clinical diagnoses in AIDS patients, especially for CMV infection.

AIDS-Related Opportunistic Infections↗
PubMed2005

Severe watery diarrhoea and bacteraemia caused by Vibrio fluvialis.

Individual cases and outbreaks of Vibrio fluvialis-associated gastroenteritis have been reported sporadically, with just one fatal bacteraemia case complicated with shigellosis described. We present a patient that suffered from severe watery diarrhoea requiring parenteral hyperalimentation. V. fluvialis simultaneously cultured from stool and blood proved to be the same strain by random amplified polymorphic DNA (RAPD) analysis. The patient was cured with intravenous administration of antibiotics and supportive treatment. To the best of our knowledge, this is the first case of gastroenteritis and bacteraemia caused by V. fluvialis.

Aged↗
PubMed2005

A prospective etiologic study of community-acquired pneumonia in Taiwan.

BACKGROUND AND PURPOSE: The treatment of community-acquired pneumonia (CAP) is complicated by the growing threat of antimicrobial resistance and the tendency to rely on empirical therapy. This study investigated the etiologic agents of adult CAP in Taiwan and the susceptibility of Streptococcus pneumoniae isolates from these patients. METHODS: A collaborative group was established in the emergency department to conduct a prospective study of the etiology of adult CAP. The etiologic agent was determined by a combination of microscopic, culture, serologic and antigen detection methods. Pneumococcal susceptibility testing was performed to determine the extent of penicillin resistance. RESULTS: A total of 100 consecutive cases of mild to moderate adult CAP prior to the severe acute respiratory syndrome epidemic were enrolled. The etiologic agent was determined in 72% of cases. The 5 most common causative pathogens were S. pneumoniae (26%), Mycoplasma pneumoniae (20%), Chlamydia pneumoniae (13%), Haemophilus influenzae (9%), and Klebsiella pneumoniae (5%). Atypical pathogens accounted for 40% of CAP. Bacteremic pneumonia was diagnosed in 6.2% of cases. Co-infections with 2 or more pathogens were found in 16% of the cases. Among the 20 isolates of S. pneumoniae, 85% (17/20) were susceptible to penicillin, 3 (15%) were intermediate, and none were resistant to penicillin. CONCLUSION: S. pneumoniae, M. pneumoniae and C. pneumoniae were the 3 leading causes of mild to moderate CAP in Taiwan. This study indicates that penicillin-resistant S. pneumoniae play a very limited role in this condition in adults.

Adolescent↗
PubMed2004

Use of MGIT 960 for rapid quantitative measurement of the susceptibility of Mycobacterium tuberculosis complex to ciprofloxacin and ethionamide.

OBJECTIVES: Tentative standards for testing MICs for Mycobacterium tuberculosis include agar dilution and the BACTEC method. However, the conventional agar dilution method requires 3-5 weeks to complete; whereas BACTEC, although a rapid test, involves the use of radioisotopes. In contrast, the MGIT 960 system uses a fluorescence quenching based oxygen sensor that can be read automatically. This system is not only robust, safe and simple, but has been validated for susceptibility tests of first-line antituberculous agents. METHODS: We evaluated 46 clinical strains of M. tuberculosis isolated from patients admitted to Kaohsiung Veterans General Hospital. Testing of MICs of ciprofloxacin and ethionamide was carried out by MGIT 960 and compared with the agar dilution method. RESULTS: Good agreement was found between MGIT 960 and agar dilution. The greatest concordance between the agar dilution and MGIT assay at +/-1 and +/-2 dilution was 80.4% and 97.8% for ciprofloxacin, and 82.6% and 93.5% for ethionamide, respectively. CONCLUSION: MGIT 960 was found to be comparable to the current NCCLS standard method, agar dilution, and has the advantage of being rapid (obtaining results within 5-17 days, average 8.9 days) and easy to achieve standardization.

Antitubercular Agents↗
PubMed2004

Double-blind, randomized, acyclovir-controlled, parallel-group trial comparing the safety and efficacy of famciclovir and acyclovir in patients with uncomplicated herpes zoster.

This randomized, double-blind, parallel-group study compared the efficacy and safety of famciclovir administered at 250 mg thrice daily with acyclovir 800 mg 5 times daily for the treatment of acute uncomplicated herpes zoster in immunocompetent adults. A total of 55 patients participated in this trial. Twenty seven patients (49.1%) were randomized into the famciclovir plus placebo treatment group and 28 (50.9%) into the acyclovir plus placebo group. Six of the 55 patients did not complete the study. Two of these patients were in the famciclovir plus placebo group and dropped out due to deviation from the study protocol. Four patients in the acyclovir plus placebo group did not complete the study protocol due to adverse events (n = 2), deviation from the protocol (n = 1), or loss to follow-up (n = 1). Treatment was initiated within 72 h of onset of the zoster rash and was continued for 7 days. When treatment was initiated within 72 h, famciclovir was as effective as acyclovir for healing the cutaneous lesion, as indicated by the time to full crusting, loss of acute phase pain, loss of vesicles, and loss of crusts. Famciclovir was well tolerated and had a more favorable adverse event profile compared to acyclovir. Constipation, hematuria, and glycosuria were the most commonly reported adverse events, but only constipation was considered to have a possible relationship to the treatment. In conclusion, famciclovir, administered less frequently and at lower unit doses than acyclovir, is an effective treatment for uncomplicated herpes zoster.

2-Aminopurine↗
PubMed2004

Quantitation of severe acute respiratory syndrome coronavirus genome by real-time polymerase chain reaction assay using minor groove binder DNA probe technology.

The ability to rapidly recognize severe acute respiratory syndrome coronavirus (SARS-CoV) as a cause of infections is critical to quickly limiting further spread of the disease. A rapid, sensitive, and specific laboratory diagnostic test is needed to confirm outbreaks of SARS-CoV infection and distinguish it from other diseases that can cause similar clinical symptoms. An improved TaqMan technology using minor groove binder (MGB) probes was used to detect and quantify SARS-CoV in suspected patients. SARS-CoV primers and probe were designed based on the open reading frame 1b sequence, which encodes coronavirus replicase protein. A linear standard curve with R2 > 0.99 was obtained, and the threshold sensitivity was 10 genome equivalents per reaction. Interassay coefficients of variation were 1.73 to 2.72%, indicating good reproducibility of this method. A total of 228 specimens from 151 suspected patients were quantified by this method, 13 specimens from 6 patients were positive with viral load range from 362 to 36,240,000 genome equivalents/mL. In conclusion, the high sensitivity and reproducibility of the real-time polymerase chain reaction SARS-CoV RNA quantitation using MGB probe allowed the screening of large numbers of clinical samples.

Base Sequence↗
PubMed2004

Characteristics of a dengue hemorrhagic fever outbreak in 2001 in Kaohsiung.

A dengue outbreak occurred in Kaohsiung City starting in July in 2001. We studied the clinical profile of all patients admitted to Kaohsiung Veterans General Hospital during this outbreak from July 2001 to January 2002. A total of 25 cases of clinically suspected dengue fever were treated during this period, and 13 of them were confirmed by laboratory results (13/25; 52%). Eleven of the 25 patients (11/25; 44%) were admitted. The mean age of the patients with laboratory confirmation of infection was 53 years (range, 7 to 85 years). Headache (7/13; 53.8%), bone pain (8/13; 61.5%), myalgia (10/13; 76.9%), abdominal pain (7/13; 53.8%), and skin rash (9/13; 69.2%) were the most common presentations. A high proportion of patients were classified as having dengue hemorrhagic fever (DHF) [6/13; 46.2%] and 2 of these patients had dengue shock syndrome (DSS) based on the World Health Organization criteria. Pretibial petechia (6/13; 46.1%), gastrointestinal bleeding (6/13; 46.1%), and hemoptysis (4/13; 30.8%) were the most common hemorrhagic manifestations. The average hospital stay was 7.1 days. Thrombocytopenia was very common and 84.6% patients had a platelet count less than 100,000/mm3. Monocytosis was found in all patients. Few patients required blood or platelet concentrate transfusion. The 2 patients who developed DSS both survived. All patients recovered completely without any obvious sequela. In conclusion, there was a high percentage of DHF among patients in the dengue outbreak in 2001. Increasing rates of DHF compared to previous reports from Taiwan may be a sign of hyperendemicity (multiple serotypes present) of the dengue virus in Kaohsiung City and its greater likelihood elsewhere in Taiwan. Prevention and control of both dengue fever and DHF have thus become increasingly important.

Adolescent↗
PubMed2003

Correlation between pyrazinamide activity and pncA mutations in Mycobacterium tuberculosis isolates in Taiwan.

A total of 76 clinical Mycobacterium tuberculosis isolates from Taiwan were tested for pyrazinamidase activity, pyrazinamide susceptibility, and pncA mutations. Frequency of resistance to PZA rose with increases in resistance to first-line drugs. Of 17 pyrazinamide-resistant strains, 7 (3 of which had not been previously described) possessed mutations in the pncA gene.

Amidohydrolases↗
PubMed2003

Expression and immunogenicity of Mycoplasma hyopneumoniae heat shock protein antigen P42 by DNA vaccination.

Mycoplasma hyopneumoniae is the etiological agent of swine enzootic pneumonia, a chronic nonfatal disease affecting pigs of all ages. The goal of this study was to design DNA vaccines by constructing plasmid pcDNA3/P42, carrying the heat shock protein gene P42 of M. hyopneumoniae, and to evaluate the immune responses elicited in BALB/c mice. The expression of P42 was first examined in transfected NIH 3T3 cells by reverse transcription-PCR to ensure that the construct was functional. The humoral and cell-mediated immune responses induced by the plasmid were further evaluated in BALB/c mice through intramuscular injection. Both immunoglobulin G1 (IgG1) and IgG2a levels were 64 times those of the control groups during the first 8 weeks. The levels of interleukin-2 (IL-2), IL-4, and gamma interferon mRNAs in the immunized animals were elevated, and the proliferation of spleen cells was also enhanced in the immunized animals. The results indicate that pcDNA3/P42 DNA immunization induces both Th1 and Th2 immune responses. In addition, antiserum from the immunized animals was found to inhibit the growth of M. hyopneumoniae. The present study reveals that DNA vaccination could be a new strategy against infection by M. hyopneumoniae and may have potential for developing vaccines for other infectious diseases as well.

3T3 Cells↗
PubMed2003

Eosinophilic meningitis caused by Angiostrongylus cantonensis associated with eating raw snails: correlation of brain magnetic resonance imaging scans with clinical findings.

Angiostrongylus cantonensis is the most common cause of eosinophilic meningitis worldwide. Human infection occurs after ingestion of the worms in raw snails or fish that serve as intermediate hosts. Two outbreaks of central nervous system infection with A. cantonensis occurred in Kaoshiung, Taiwan, during 1998 and 1999 among Thai laborers who ate raw snails. A detailed clinical studies of 17 of these patients was conducted, including study of 13 patients who underwent magnetic resonance imaging (MRI) scans of the brain. The MRI scans revealed high signal intensities over the globus pallidus and cerebral peduncle on T1-weighted imaging, leptomeningeal enhancement, ventriculomegaly, and punctate areas of abnormal enhancement within the cerebral and cerebellar hemisphere on gadolinium-enhancing T1 imaging, and a hyperintense signal on T2-weighted images. There was a significant correlation between severity of headache, cerebrospinal fluid (CSF) pleocytosis, and CSF and blood eosinophilia with MRI signal intensity in T1-weighted imaging (P < 0.05). Eosinophilic meningitis produced by A. cantonensis needs to added to the list of causes of hyperintense basal ganglia lesions found on T1-weighted MRI scans in tropical countries.

Adult↗
PubMed2003

Outbreak of aseptic meningitis among adults in southern Taiwan.

A total of 38 adult cases of aseptic meningitis were diagnosed based on clinical manifestations as well as examination of cerebrospinal fluid at Kaohsiung Veterans General Hospital in 2001. The majority (31 cases, 82%) of cases occurred between June and August, and most (33 cases, 87%) of them aged from 18 to 35 years (median age, 25 years). The male-to-female ratio was 2.16:1. Common clinical presentations included headache, fever, nausea or vomiting, and symptoms of common cold. On initial cerebrospinal fluid examination, white cell counts were above 500 cells/mm3 in 7 (18%) cases, and neutrophils predominated in 10 (28%) of 36 cases. The cerebrospinal fluid protein concentration was below 100 mg/dL in 29 (77%) of 38 cases, and hypoglycorrhachia (cerebrospinal fluid/serum glucose ratio <0.5) was seen in 9 (24%) cases. Enterovirus as a definite etiology was confirmed by isolation from cerebrospinal fluid in 17 (45%) of 38 cases and was the presumptive etiology by isolation from the stool or throat swab in 2 (5%) cases. Of the 19 cases with positive viral isolation, echovirus serotype 30 accounted for the majority (15 cases, 79%), followed by echovirus serotype 6 (3 cases, 16%), with one (5%) case undetermined. The viral isolation rate from cerebrospinal fluid correlated to the day of cerebrospinal fluid sampling after disease onset (chi2 = 12.05, p = 0.007). All patients were discharged uneventfully without receiving antibiotic therapy.

Adolescent↗