Biomedical subjects

K Liu

Publications and source records attributed to K Liu.

At least 253 records · Page 14Linked to original sources

PubMed1998

Detection of filarial larvae in mosquitoes with oligonucleotide probe.

OBJECTIVE: To investigate a new way to detect filarial larvae in mosquitoes and apply it to the surveillance of filariasis. METHODS: An oligonucleotide probe that was species-specific to W. malayi was synthesized and marked with 32P using molecular biological technique. Then the probe was tested with dot hybridization in detection of W. malayi filarial larvae from mosquitoes. RESULTS: The minimal detectable limit was found to be 2 ng DNA of filarial larvae or microfilaria (Mf.), with no cross reaction with other animal filariae. A single larva can be detected when infected mosquitoes were tested one by one. One infected mosquito can be detected from a group of 20 mosquitoes tested together. CONCLUSIONS: Our probe is sensitive and specific. It is practical to apply our probe to mosquito surveillance in Brug's filariasis endemic areas.

Animals↗

PubMed1998

Report from the Chinese Bone Marrow Transplant Registry with special regard to autologous transplant.

OBJECTIVE: To study the current status of autotransplantation in the People's Republic of China and facilitate national and international exchange of relevant experiences. METHODS: On the basis of the materials collected from the member units around our country, various statistical methods, such as Kaplan-Meier and chi 2 tests, were used to estimate the probabilities of leukemia free survival (LFS). RESULTS: Up to July 31, 1996, a total of 1213 cases of stem cell transplantation (SCT) were performed in 61 medical units in the People's Republic of China, and 22 of the units are able to perform both allogeneic SCT (Allo-SCT) and autologous-SCT (ASCT). The remaining 41 units had the capacity only to perform autologous-SCT. There were 772 cases of autologous SCT performed. The three year probabilities of leukemia free survival for acute mylogeneous leukemia complete remission (AML-CR1) and acute lymphocyte leukemia complete remission (ALL-CR1) recipients were 56% and 42.8%, respectively. The three year probabilities of relapse were 44.8% and 47%, respectively. Among the patients with acute leukemia who attained CR1 within 40 days of diagnosis and who subsequently underwent autotransplantation within three to six months, the three year probabilities of LFS for acute mylogenous leukemia (AML) and acute lymphocyte leukemia (ALL) were 72% and 50%, respectively. CONCLUSIONS: Patients who attained complete remission (CR1) within 40 days after diagnosis and underwent subsequent autologous-SCT within three to six months of CR1 enjoyed a significantly increased LFS.

Adult↗

PubMed1998

[Spinal segment distribution of neural innervation related to houhai acupoint and compared with zusanli and dazhui acupoints in domestic chicken].

OBJECTIVE: The aim of this study was to demonstrate the spinal segmental innervation of Houhai, Dazhui and Zusanli acupoints in domestic chicken. METHODS: The horseradish peroxidase conjugated cholera toxin B subunit (CB-HRP) was injected into the regions of the three acupoints namely, Houhai Dazhui and Zusanli respectively in separate groups of chicken. The frozen sections of spinal cord and dorsal ganglia were prepare for labelling using TMB as a chromogen. RESULTS: (1) In Houhai group the anterograde transganlionic labelling terminals were densely distributed in the dorsal horn and dorsal commissure nucleus. The moto-neurons in ventral horn labelled retrogradely appeared fine arborization of dendrites. There were labelled cell bodies in the dorsal region of the ventral horn (lamina VII) or dorsal commissure nucleus. (2) In Dazhui group, the bundles of labelled fibers presented from laminea I and II to IX in the caudal cervical enlargements and two upper thoracic segments. The labelled motoneurons were shown in medial and lateral groups. The most numourous of labelled ganglionic cells appeared in this group. (3) The labelling sensory ganglionic neurons and their terminals in spinal cord related Zusanli acupoint were overlaped with those related Houhai acupoint. The largest numbers of the labelled ventral motoneurons occured in the Zusanli group. CONCLUSIONS: The results demontrated the patterns of segmental innervation corresponding respectively to Houhai, Dazhui, and Zusanli acupoints. The anterograde afferent labelling terminals and interrelationship of the dendritic arborization of retrograde labelling motoneurons (somatic or visceral) provided neuroanatomical evidences for the innervation of the acupoints.

Acupuncture Points↗

PubMed1998

Determinants and costs of Medicare post-acute care provided by SNFs and HHAs.

Provisions in the 1997 Balanced Budget Act affecting Medicare skilled nursing facility (SNF) and home health agency (HHA) services heighten the importance of knowing more about beneficiary, market, and policy factors that impact use of post-acute care and the costs of such services. This study used data from the Medicare Current Beneficiary Survey and other sources to address these issues. Findings shed light on responses that need to be monitored in light of the recently mandated policies and other SNF and HHA options that are being considered.

Activities of Daily Living↗

PubMed1998

Elimination of hypercapnia may postpone the clinical presentation of malignant hyperthermia: a case report.

Malignant hyperthermia is a rare complication in clinical anesthesia, especially associated with the administration of succinylcholine or inhalation anesthetics. A 19-year-old patient, suffering from traumatic mandible fracture, underwent open reduction under general anesthesia. Unfortunately, following administration of succinylcholine, he also suffered severe facial twitch and the first episode of hypercapnia. After adequate management, the symptoms subsided. However, two hours later, the hypercapnia recurred, combined with progressive elevation of body temperature. After administration of intravenous dantrolene 120 mg, the patient's condition became stable and the procedure was completed without sequelae. As the muscle contracture test is not available in Taiwan, the clinical grading scale is presented as an alternative diagnostic method for malignant hyperthermia.

Adult↗

PubMed1998

Artificial neural networks in pediatric urology: prediction of sonographic outcome following pyeloplasty.

PURPOSE: Computerized artificial neural networks are analogous to biological neuronal systems. Since they may be trained to recognize the relevance of complex patterns in data, neural networks may be useful for decision making in the multifactorial management of ureteropelvic junction obstruction. We determine the ability of a customized neural network to predict sonographic outcome after pyeloplasty in children with ureteropelvic junction obstruction. MATERIALS AND METHODS: A data set was constructed with 242 demographic, clinical, radiological and surgical elements. We analyzed the available retrospective data in 100 consecutive children who underwent unilateral pyeloplasty for ureteropelvic junction obstruction chosen from all 144 surgically treated for ureteropelvic junction obstruction between 1993 and 1995. One radiologist reviewed all film data and provided a final sonographic outcome designation in each case. We wrote a set of computer programs to construct a neural network. A composite 4-layer network was built with output nodes representing 4 possible sonographic outcomes. The 100 patient data set was randomly divided into 84 training and 16 testing examples. RESULTS: The neural network correctly predicted all 5 of 5 significantly improved, 7 of 7 improved, 2 of 2 same and 2 of 2 worse sonogram results after pyeloplasty. Therefore, sensitivity and specificity were 100% for all 4 outcomes. Linear regression analysis of the data yielded inferior sensitivity and specificity values (52 to 94%), confirming that ureteropelvic junction obstruction is a nonlinear data analysis problem. CONCLUSIONS: The 100% accuracy, sensitivity and specificity of our neural network in this pilot study provide evidence of the value of the neural computational approach for the modern exploration and modeling of the clinical problem of pediatric ureteropelvic junction obstruction.

Child↗

PubMed1998

Experimental study on the scavenging effects of ginsenosides on oxygen free radicals using model of heterotopic heart transplantation in rats.

Oxygen-derived free radicals play an important role in myocardial injury associated ischemia and reperfusion. To investigate whether ginsenosides, as an additive agent of cardioplegic solution, can decrease toxicity of oxygen free radicals in myocardial injury, a heterotopic heart transplantation model in Wistar rats was employed. St. Thomas II cold cardioplegia containing ginsenosides 80 mg/l was used in the experimental group. St. Thomas II cold cardioplegia alone was used in the control group. After global ischemia for 60 minutes and reperfusion for 30 minutes of a transplanted heart, SOD activity in the myocardium treated with ginsenosides was significantly higher than that in the control group (N=10, p< 0.01), whereas the MDA in the myocardium treated with ginsenosides were markedly lower than that of the control group (p< 0.01). The amounts of oxygen free radicals in the myocardium treated with ginsenosides were significantly lower than that of the control group (p <0.001). This study demonstrates that ginsenosides, as a proper additive agent of cardioplegic solution, can decrease toxicity of oxygen free radicals, suggesting one of the mechanisms for its protective effects against myocardial ischemia and reperfusion injury.

Animals↗

PubMed1998

Prospective and randomized trial of intravenous tenoxicam versus fentanyl and tramadol for analgesia in outpatient extracorporeal lithotripsy.

BACKGROUND: As extracorporeal shock wave lithotripsy (ESWL) is frequently carried out on an outpatient basis, it is crucial to choose an adequate analgesic with less adverse effect. This study evaluated the use of three different intravenous agents: fentanyl, tramadol HCl and tenoxicam in ESWL. METHODS: One hundred and twenty patients undergoing lithotripsy were randomly assigned to receive either intravenous fentanyl 1 microgram/kg, tramadol HCl 1.5 mg/kg or tenoxicam 0.3 mg/kg before lithotripsy. Pain intensity was recorded using verbal rating pain scales (VRPS). Cases without adequate analgesia (VRPS > 4) or could not tolerate the pain, additional bolus of fentanyl 25 micrograms were given until adequate analgesia was achieved. Side effects were recorded as well. RESULTS: No significant differences were found among groups in demographic data, VRPS, number of total shock waves, cases with supplementary fentanyl, mean dose of supplementary fentanyl or the incidence of dizziness. However, the incidence of nausea or vomiting was significantly higher in fentanyl and tramadol groups comparing with tenoxicam group (15.0% and 25.0% vs. 0.0%). Oxygen saturation in fentanyl group was also significantly lower than the other two groups (p < 0.01). In addition, VRPS had a significant correlation with voltage intensities (p < 0.05). CONCLUSIONS: Lithotripsy can be satisfactorily performed by employing fentanyl, tramadol or tenoxicam for analgesia; tenoxicam apparently offers a better analgesic quality with less side effect. Furthermore, the need for stronger analgesia during larger voltage intensity should be tailored to the needs of the individuals.

Ambulatory Surgical Procedures↗

PubMed1998

Clinical care of osteoarthritic knee with knee orthoses.

We reviewed the efficiency of knee orthosis wearing of 11 patients suffering from knee osteoarthritis (OA). The authors found that knee orthoses could increase mechanical stability of the OA knee joints and relieve pain subjectively, which improved patients' daily lives, particularly for those patients under low physiologic knee loading conditions.

Adult↗

PubMed1997

Temporal expression of urokinase type plasminogen activator, tissue type plasminogen activator, plasminogen activator inhibitor type 1 in rhesus monkey corpus luteum during the luteal maintenance and regression.

Proteolytic activity generated by the plasminogen activator (PA) system has been associated with many biological processes. Using a pregnant mare serum gonadotropin (PMSG)/human chorionic gonadotropin (hCG)-induced rhesus monkey corpus luteum (CL) model, we have studied how urokinase-type plasminogen activator (uPA), tissue-type plasminogen activator (tPA), and plasminogen activator inhibitor type 1 (PAI-1), are temporally expressed in CL of rhesus monkey at the luteotropic and luteolytic periods. Slot blot analysis and in situ hybridization were performed to analyze the expression and distribution of uPA and PAI-1 messenger RNA (mRNA). Fibrin overlay was used to detect uPA and tPA activities. We found that uPA is the dominating PA in luteotropic CL in the monkey. Abundant expression of PAI-1 mRNA was detected. The highest expression of uPA and PAI-1 mRNA was observed at the luteotropic period, while their expression decreased approximately 50% at early luteal regression defined by considerably decreased serum progesterone levels, and remained at very low levels at the late stage of luteal regression. We also observed an increased tPA activity at the time of luteal regression. Moreover, the exogenous tPA could inhibit the progesterone production in cultured luteal cells from 13-day-old monkey CL. We also used LH receptor mRNA expression as a mark for the luteal phases. A highly expressed, evenly distributed LH receptor mRNA was detected in CL during the luteotropic phase, while its expression decreased at day 13 coinciding with the reduction of progesterone production. We conclude that proteolysis mediated by uPA and regulated by PAI-1 may play a role in the luteal maintenance, while tPA may participate in the luteal regression in the rhesus monkey.

Animals↗

PubMed1997

Immunotherapy of tumors with autologous tumor-derived heat shock protein preparations.

Immunotherapy of mice with preexisting cancers with heat shock protein preparations derived from autologous cancer resulted in retarded progression of the primary cancer, a reduced metastatic load, and prolongation of life-span. Treatment with heat shock protein preparations derived from cancers other than the autologous cancer did not provide significant protection. Spontaneous cancers (lung cancer and melanoma), chemically induced cancers (fibrosarcoma and colon carcinoma), and an ultraviolet radiation-induced spindle cell carcinoma were tested, and the results support the efficacy of autologous cancer-derived heat shock protein-peptide complexes in immunotherapy of cancers without the need to identify specific tumor antigenic epitopes.

Animals↗

PubMed1997

Logistic analysis of shovel and Carabelli's tooth traits in a Caucasoid population.

Caucasoid populations differ from Mongoloids by having a high prevalence of Carabelli's trait and a low prevalence of shovel trait. This study was conducted to investigate the association between the shovel and the Carabelli's traits in a Caucasoid population. The research design sought a Caucasoid population at Milwaukee of Wisconsin in United States. The Caucasoid group selected for study was the European descendant. The effects of sex and age on Carabelli's trait were controlled in this investigation, as was the association between tooth size and Carabelli's trait. Results show that males were more likely to have Carabelli's trait expressed on teeth than females. The buccolingual diameter of Carabelli's trait teeth was larger than that of teeth without the trait. After adjusting for sex, age, and tooth size, the existence of the shovel trait decreased the likelihood of having Carabelli's trait which shows an significant effect.

Asian People↗

PubMed1997

DNA sequence encodes information for nucleosome array formation.

We have examined the effects of base sequence on nucleosome array formation using randomly selected chicken genomic DNA sequences. DNA clones were assembled into chromatin under identical conditions using a defined in vitro system capable of generating physiologically spaced nucleosomes on some sequences. The nucleosome arrangements in native chromatin on the selected sequences were also examined in liver nuclei. Variations in nucleosome ladders were found among the different sequences that were similar in vitro and in nuclei. Differences in both the degree of regularity of nucleosome arrays and in the value of the nucleosome repeat length were observed. Analysis of an approximately 100 kilobase-pair contiguous region using cosmid clones suggested that well-ordered regions of chromatin, generally less than two kilobase-pairs in extent, alternate with less-ordered regions. This mosaic arrangement for chromatin organization appears to be largely a consequence of information encoded in the DNA base sequence. Nucleosome ordering with a 210 base-pair periodicity in a highly ordered ten-nucleosome array appeared to result from linker histone-dependent alignment with respect to each of two positioned nucleosomes, approximately 1000 base-pairs apart.

Animals↗

PubMed1997

Measurement of relative quantities of different HLA-A and -B mRNAs in cells by reverse transcription-polymerase chain reaction and denaturing gradient gel electrophoresis.

In order to determine the relative quantities of different HLA-A and -B mRNAs in cells, we have developed a simple and reliable method by using reverse transcription-polymerase chain reaction (RT-PCR), denaturing gradient gel electrophoresis (DGGE) and phosphor imaging analysis. Cytoplasmic RNA from lymphoblastoid cell lines with well-characterized HLA phenotypes are reversely transcribed with a primer specific for all HLA-A and -B antigens. The first-strand cDNA is used as template for quantitative PCR. The primer pair used for quantitative PCR are specific for all class I HLA and one of the primers is labeled with [gamma-32P]ATP. The amplified sequences include parts of exon 2 and exon 3 which contain most polymorphic residues in class I HLA molecules. The RT-PCR products containing the amplified HLA-A and -B sequences are separated by DGGE. The radioactivities of different DNA bands separated in denaturing gradient polyacrylamide gels are measured by phosphor imaging and used to determine the relative amounts of HLA-A and -B mRNAs. This approach is validated by using samples containing known quantities of different HLA-A and -B mRNA transcripts and confirmed by S1 nuclease protection assay. The combined RT-PCR/DGGE approach therefore provides a simple and reliable method for quantitation of relative amounts of different HLA-A and -B mRNAs in cells. This method should also be useful for studying the expression of other highly conserved and duplicated genes.

Cell Line, Transformed↗

PubMed1997

Fish consumption and the 30-year risk of fatal myocardial infarction.

BACKGROUND: Epidemiologic data on the possible benefit of eating fish to reduce the risk of coronary heart disease have been inconsistent. We used data from the Chicago Western Electric Study to examine the relation between base-line fish consumption and the 30-year risk of death from coronary heart disease. METHODS: The study participants were 1822 men who were 40 to 55 years old and free of cardiovascular disease at base line. Fish consumption, as determined from a detailed dietary history, was stratified (0, 1 to 17, 18 to 34, and > or = 35 g per day). Mortality from coronary heart disease, ascertained from death certificates, was classified as death from myocardial infarction (sudden or nonsudden) or death from other coronary causes. RESULTS: During 47,153 person-years of follow-up, there were 430 deaths from coronary heart disease; 293 were due to myocardial infarctions (196 were sudden, 94 were nonsudden, and 3 were not classifiable). Cox proportional-hazards regression showed that for men who consumed 35 g or more of fish daily as compared with those who consumed none, the relative risks of death from coronary heart disease and from sudden or nonsudden myocardial infarction were 0.62 (95 percent confidence interval, 0.40 to 0.94) and 0.56 (95 percent confidence interval, 0.33 to 0.93), respectively, with a graded relation between the relative risks and the strata of fish consumption (P for trend = 0.04 and 0.02, respectively). These findings were accounted for by the relation of fish consumption to nonsudden death from myocardial infarction (relative risk, 0.33; 95 percent confidence interval, 0.12 to 0.91; P for trend= 0.007). CONCLUSIONS: These data show an inverse association between fish consumption and death from coronary heart disease, especially nonsudden death from myocardial infarction.

Adult↗

PubMed1997

Lower gastrointestinal tract perforation in preterm infants treated with dexamethasone for bronchopulmonary dysplasia

Two cases of ileal perforation in preterm infants treated with high-dose dexamethasone for bronchopulmonary dysplasia are described. Corticosteroid-induced gastroduodenal haemorrhage or perforation has been well documented, but less known to most clinicians is that the lower gastrointestinal tract can also be involved. Unlike previous reported cases in which affected infants deteriorated rapidly and became moribund within hours of onset of symptoms, "silent" perforations detected on routine radiograph or escaping clinical recognition until at an advanced stage can be the initial presentation. The need for greater vigilance and a low threshold for abdominal investigations are emphasised in preterm infants treated with dexamethasone.

Journal Article↗

PubMed1997

The Water Dipole Moment in Water Clusters

The average dipole moment of a water molecule in the condensed phase is enhanced by around 40 percent relative to that of an isolated monomer. This enhancement results from the large polarization caused by the electric field induced by surrounding monomers. A quantitative molecular description of this polarization is essential for modeling aqueous solvation phenomena. This combined theoretical and experimental study of dipole moments in small water clusters provides such a description and also gives insights into the structure of liquid water.

Journal Article↗

PubMed1997

Characterization of oligonucleotide metabolism in vivo via liquid chromatography/electrospray tandem mass spectrometry with a quadrupole ion trap mass spectrometer.

The pattern of nuclease degradation observed for an antisense phosphorothioate oligonucleotide in pig kidney was determined using liquid chromatography/electrospray mass spectrometry (LC/ESI-MS) and LC/ESI-MS/MS with a quadrupole ion trap mass spectrometer. Metabolites were separated by length using reversed-phase high-performance liquid chromatography with aqueous hexafluoropropan-2-ol-triethylamine and a methanol gradient. The individual masses of metabolites in each LC peak were determined via deconvolution and converted into potential nucleotide compositions. The nucleotide composition was used to locate metabolites within the known oligomer sequence. The identity of metabolites was confirmed using on-line LC/MS/MS to generate fragment ions suitable for sequence verification. A limited number of shorter oligonucleotide fragments were observed, suggesting that metabolism in vivo may be sequence dependent.

Animals↗