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Biomedical subjects

C K Tseng

Publications and source records attributed to C K Tseng.

At least 19 recordsLinked to original sources
PubMed1992

[The functional assessment of chronic pain patients activity of daily living and psychosocial disability].

The purpose of this study was to investigate the impact of activity of daily living and psychosocial function in patients with chronic nonmalignant pain. From Jun. 1989 to Nov. 1989, one hundred and eleven cases were assessed by Sickness Impact Profile (SIP) and Taita Symptom Check List (TSCL) to evaluate the disabilities associated with chronic pain. Patients showed significant impairment in the functions of physical psychosocial work and recreational activities. It was also apparent that the psychosocial disabilities were more severe than physical disabilities. Specifically, they showed anxiety depression and significant somatization. Analysis by stepwise multiple regression indicates that sex age educational level employment status diagnosis and pain intensity were the significant influencing factors related to the disabilities of activity of daily living and psychosocial function. The results supported the validity of the SIP as a measurement of functional status with chronic pain patients. Specifically, the psychosocial dimension was significantly correlated with the psychological and psychosocial distress categories of the TSCL. Based upon its reliability validity breadth of assessment and ease of administration, the SIP appeared to be well suited for the assessment of patients with chronic pain and for evaluating the efficacy of multidisciplinary pain treatment.

Activities of Daily Living↗
PubMed1992

[The safety of geriatric anesthesia].

UNLABELLED: Perioperative abnormalities and complications were reviewed in 556 geriatric patients retrospectively to assess the safety of geriatric anesthesia. Preoperatively, the percentages of cases with cardiovascular and pulmonary abnormalities were 49.6% (276 cases) and 21.8% (121 cases) respectively. 77 percent of out patients (428 cases) were in the ASA class II physical status. The most common intraoperative complication was blood pressure instability and the incidence was noted to be of 34.8% (130 cases) with general anesthesia and of 15.8% (26 cases) with regional anesthesia. With general anesthesia, incidence for postoperative events such as non-fatal complications (i.e., sore throat and eye dryness), cardiovascular abnormalities and pulmonary disorders were found to be 39.0% (146 cases), 22.2% (83 cases) and 6.2% (23 cases) respectively. With regional anesthesia, the most common postoperative event was blood pressure instability (incidence: 21.2%, 35 cases). Total mortality rate of the first 15 postoperative days was 2.0% (11 cases). Mortality rate in elective and emergency surgery was 1.1% (5 cases) and 6.8% (6 cases) respectively. Causes of death were mainly related to illness deterioration (cancer and infection) or location of surgery. Death due to anesthetic mishap was nil in this study. IN CONCLUSION: Most geriatric patients had more than one system or one organ dysfunction before operation. Cardiovascular instability was the most common intraoperative complication. Postoperative mortality correlates closely with the preoperative ASA physical status. Mortality rate was significantly higher in emergency cases than in elective cases. A thorough pre-operative assessment and proper perioperative management are mandatory in geriatric anesthesia.

Aged↗
PubMed1992

[The effect of nitrous oxide anesthesia combined with low dose alfentanil for minor surgery of short duration].

This study was conducted in 30 adult patients with ASA class I-II physical status who received minor operations. Anesthetic induction was achieved by injecting thiopental 4 mg/kg intravenously in addition to N2O/O2 (4L/2L) delivered via Ventri Mask, followed by alfentanil 7 micrograms/kg intravenously 3 min later. Maintenance of anesthesia was accomplished by N2O/O2 in conjunction with alfentanil 0.25-2.5 micrograms/kg/min, delivered intravenously by a syringe pump. Our result showed that in an operation of average duration around 40.2 +/- 10.5 min., the average dose of alfentanil used was 0.62 +/- 0.15 micrograms/kg/min. The respiration rate fell from 13.4 +/- 0.4 cpm to 8.4 +/- 1.1 cpm 2 min later following alfentanil injection, which was statistically significant. SaO2 fell from 97.9 +/- 0.4% to 94.0 +/- 0.8% 3 min after alfentanil injection, which was statistically significant. End-tidal carbon dioxide partial pressure elevated from 39.4 +/- 0.6 mmHg to a peak of 45.3 +/- 1.2 mmHg 5 min after alfentanil injection which was also statistically significant. Temporary apnea was noted in 3 cases, but they all resumed spontaneous respiration after a short period of assisted ventilation. Changes in systolic and diastolic pressure during anesthesia were not marked. Pulse rate was noted to decrease from 80.3 +/- 2.7 bpm to 70.5 +/- 2.0 bpm 1 min after alfentanil injection, which was statistically significant (p less than 0.05). After discontinuation of N2O, the time required to regain the ability to follow orders of "open your eyes," "show your thumb" and "say your name" in sequence was 72.5 +/- 10.6s, 88.2 +/- 11.6s, 128.1 +/- 23.0s, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

A ring-enlarged oxetanocin A analogue as an inhibitor of HIV infectivity.

Two ring-expanded analogues (compounds 2 and 3) of the anti-HIV fermentation product oxetanocin A (1) were synthesized from commercially available diacetone D-glucose. Antiviral testing against HIV in ATH8 cells revealed that the ring-expanded analogue 2 possessed a similar activity profile as oxetanocin A. Neither compound, however, was capable of providing full protection to the cells against HIV infection. The isomeric ring-expanded analogue 3 was totally devoid of anti-HIV activity. Molecular modeling suggested that while oxetanocin A and compounds 2 and 3 share a large common substructure with the potent anti-HIV drug, dideoxyadenosine (ddA), the extra hydroxymethyl substituent may contribute negatively to the binding of these molecules to a critical enzyme. The negative contribution may be less important in oxetanocin and isomer 2 than in isomer 3. From these studies it would appear that both oxetane and tetrahydrofuran rings are equivalent templates to support the adenine base in terms of anti-HIV activity.

Adenine↗
PubMed1991

[Intravenous propofol as a supplement in epidural anesthesia].

Under study were thirty patients of ASA class I-II scheduled for lower abdominal and lower extremities surgery. Premedication included intramuscular injection of pethidine, atropine and prochlorperazine. Epidural anesthesia was accomplished with 12-15 ml 2% lidocaine with epinephrine (1:80,000). Thirty minutes later, when blood pressure returned to control value, patients were put to sleep by 2 mg/kg propofol and the sleep was maintained with continuous infusion of propofol at a rate of 6 mg/kg/h. Infusion rate was adjusted when necessary. Patients breathed room air spontaneously through the whole course of anesthesia. The results showed that all patients fell to sleep within 28.3 +/- 2.7 s after intravenous injection of propofol 2 mg/kg. Sleeping dose was satisfactorily achieved using a mean infusion rate of 6.1 +/- 1.7 mg/kg/h. The mean time from the end of the infusion of propofol to opening of the eyes on command and telling the correct date of birth were 7.9 +/- 2.8 min and 9.9 +/- 3.8 min respectively. Two minutes after injection, there were significant decrease in systolic pressure, diastolic pressure, cardiac output, and stroke volume with a mean of 17.9 +/- 3.8%, 18.8 +/- 3.3%, 7.6 +/- 0.5% and 11.1 +/- 1.9% respectively. Two patients (7%) developed apnea after 2 mg/kg propofol which was considered to be the most serious side effect. Propofol infusion had to be stopped in 13% patients due to a 30% fall of arterial blood pressure during maintenance. In the recovery stage, no other complications were noted except one patient who felt dizziness. Propofol, used as the supplementary sedative, provides satisfactory result for surgery under epidural anesthesia.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Syphilis superinfection activates expression of human immunodeficiency virus I in latently infected rabbits.

Superinfection of latently human immunodeficiency virus (HIV)-infected rabbits with either Treponema pallidum or Shope fibroma virus (SFV) activates HIV expression. In addition, HIV-infected rabbits demonstrate prolonged cutaneous lesions (chancres) after intracutaneous challenge with T. pallidum, the causative agent of syphilis. Rabbits were infected by intravenous inoculation of 3 x 10(7) human T-cell lymphotrophic virus type III (HTLV-III)/B10 (HIV-1)-infected H9 (human) cells. Five weeks after initial infection, integrated HIV-1-specific DNA sequences were detected in the DNA of the peripheral blood lymphocytes of only one of eight rabbits using polymerase chain reactions (PCR); human DNA could not be detected at this time. Furthermore HIV infection could not be demonstrated by either seroconversion or PCR during the next 6 months. All HIV-infected rabbits remained clinically healthy and had normal white blood cell counts. Six months after HIV infection, four HIV-infected and two noninfected controls were superinfected with 10(6) T. pallidum in eight skin sites in the shaved skin of the back, and four infected and two control animals were challenged with an intradermal injection with SFV. After infection with either syphilis or SFV, the DNA from the white blood cells of all eight HIV-infected rabbits contained HIV sequences, and HIV sequences were demonstrated in dermal mononuclear cells of the syphilitic lesions by in situ hybridization. The SFV-induced tumors were rejected normally in the HIV-infected rabbits, but four of the four rabbits challenged with T. pallidum had delayed development of cutaneous lesions and three of four demonstrated larger and more prolonged lesions. White blood counts, mitogen responses, and interleukin-2 production remained within normal limits, and seroconversion for HIV was not detected. Three of four rabbits in a second group, challenged with T. pallidum 4 months after HIV-inoculation, also had delayed healing of syphilitic lesions. These results indicate that latent HIV-infection of rabbits may be activated by immunostimulation and that latently HIV-infected rabbits have impaired delayed hypersensitivity reactions. It is hypothesized that true latent HIV-infection in the rabbits is in monocytes and postulated that further immunostimulation may produce infection of lymphocytes and activation of disease.

Animals↗
PubMed1990

Molecular signals in B cell activation. I. Differential refractory effects of incomplete signaling by ionomycin or PMA relate to autocrine IL-2 production and IL-2R expression.

The molecular signals required by resting (G0) B cells for the induction of cell cycle entry, IL-2 production, and high-affinity IL-2 receptor (IL-2R) expression were defined and the effects of incomplete activation signals on the subsequent response to complete signals were examined. Highly enriched rabbit peripheral blood B cells were activated with a calcium ionophore, ionomycin, and a protein kinase C (PKC) activating phorbol ester, phorbol myristate acetate (PMA). It was observed that cell cycle entry to early G1 was induced by either reagent acting alone, but both reagents were required to stimulate IL-2 production, IL-2R expression, and DNA synthesis. These effects of ionomycin and PMA were shown to be mediated by increased intracellular calcium ion concentration [Ca2+]i and PKC activation, respectively. Although, increased [Ca2+]i or PKC activation each led to cell cycle entry, the subsequent response of these preactivated cells to complete activation with both signals was different: Cells pretreated with PMA alone for up to 24 hr could progress further to DNA synthesis after the addition of ionomycin. In contrast, cells activated with ionomycin alone, or those cultured without any stimulus, progressively lost the ability to show DNA synthesis after complete activation. The failure to progress to DNA synthesis in these two cases was, however, differentially regulated by the ability of these cells to produce IL-2 and to express IL-2R. Ionomycin-pretreated cells retained the ability to produce IL-2 but showed about 70% reduction in the numbers of IL-2R; whereas cells cultured without any stimulus lost the ability to produce IL-2 after subsequent complete activation, but showed lesser reduction in IL-2R expression.

Animals↗
PubMed1990

Molecular signals in B cell activation. II. IL-2-mediated signals are required in late G1 for transition to S phase after ionomycin and PMA treatment.

We report that sustained increase of intracellular calcium ion concentration and protein kinase C (PKC) activation maintained throughout the G1 phase of cell cycle do not provide sufficient signals to cause S-phase entry in rabbit B cells, and that additional signals transduced by IL-2 and IL-2 receptor interaction are essential for G1 to S transition. We have shown earlier that rabbit B cells can be activated to produce IL-2 and express functional IL-2 receptors after treatment with ionomycin and PMA. Herein we have compared the response of rabbit PBLs, which contain about 50% T cells, with those of purified B cells. After activation with ionomycin or PMA, comparable numbers of PBLs and B cells entered the cell cycle; but DNA synthesis by the PBL cultures was three to four times higher than that of cultures of purified B cells. Interestingly, IL-2 production by the PBL cultures was also three to four times higher than in B cell cultures, suggesting an involvement of IL-2 in inducing DNA synthesis in these cells. The hypothesis that IL-2, which is produced in early G1, acts in late G1 and is required for G1 to S transition in B cells was supported by the following observations: (i) IL-2 production by B cells was detected as early as 6 hr after activation and preceded DNA synthesis by at least 24 hr. (ii) B cell blasts in G1 (produced by treatment of resting B cells with ionomycin and PMA) showed DNA synthesis in response to IL-2, but showed very little DNA synthesis in response to restimulation with ionomycin and PMA. (iii) A polyclonal rabbit anti-human IL-2 antibody caused nearly complete inhibition of DNA synthesis by B cells activated by ionomycin and PMA. (iv) A PKC inhibitor, K252b, inhibited DNA synthesis in ionomycin and PMA-stimulated cells if added at the beginning of culture but was not inhibitory if added 16 hr later. We conclude that increased [Ca2+]i and PKC activation are not sufficient signals for G1 to S transition in B cells; entry into S is signaled by IL-2, and IL-2-mediated signal transduction probably does not involve increased [Ca2+]i or PKC activation.

Animals↗
PubMed1990

Interleukin 2 produced by activated B lymphocytes acts as an autocrine proliferation-inducing lymphokine.

Normal peripheral blood B cells produce a soluble factor after activation that is functionally indistinguishable from interleukin 2 (IL 2) and can support B cell proliferation in vitro. Purified rabbit peripheral blood B cells, when stimulated with a combination of ionomycin (0.5 microgram/mL) and phorbol myristate acetate (PMA) (1 ng/mL), secreted a soluble factor in the culture medium that supported the IL 2-dependent cell line CTLL-2. The ability of these supernatants to support CTLL-2 growth was almost completely blocked by rabbit antibodies against human recombinant IL 2 and by the anti-IL 2 receptor monoclonal antibody 7D4. These data strongly suggest that the growth factor secreted by rabbit B cells is IL 2. To examine the possibility that the IL 2 activity detected in the B-cell cultures may be derived from residual T cells, B cells were further purified by successive panning with a pan-T-cell monoclonal antibody, L11-135, and goat anti-rabbit IgG. These highly purified B cells produced levels of IL 2 activity comparable to those produced by the initial B cell populations. Comparison of IL 2 production by decreasing numbers of purified T cells and purified B cells also indicated that the B cells were the source of IL 2 activity. Supernatants of activated B cells could support proliferation of B-cell blasts, and this activity could be completely absorbed by CTLL-2 cells, indicating that IL 2 is a major growth factor for B cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Acid-stable 2'-fluoro purine dideoxynucleosides as active agents against HIV.

2',3'-Dideoxy purine nucleosides have anti-HIV activity in vitro and the inosine analogue is being clinically evaluated. The instability of these compounds toward acidic conditions complicates oral administration. The effect of the addition of a fluorine atom to the 2'-position was investigated by preparing the fluorine-containing 2'-erythro and 2'-threo isomers of ddA and the threo isomer of ddI. All fluorine-containing compounds were indefinitely stable to acidic conditions which completely decomposed ddI (1) and ddA (2) in minutes. While the fluorine-containing erythro isomer, 5, was inactive, the threo isomers, 2'-F-dd-ara-A (3) and 2'-F-dd-ara-I (4), were just as potent and active in protecting CD4+ ATH8 cells from the cytopathogenic effects of HIV-1 as the parent drugs. Exposure to pH 1 at 37 degrees C prior to testing destroyed the activity of ddA and ddI but left the anti-HIV properties of 3 and 4 unchanged. The fluorinated analogues also protected cells exposed to HIV-2 and inhibited gag gene product expression but not as effectively as the parent compounds. The fluorine-containing analogues appear to be somewhat more toxic in vitro to the antigen- and mitogen-driven proliferation of immunocompetent cells than their corresponding parent compounds.

Antiviral Agents↗
PubMed1990

Expression of p55 (Tac) interleukin-2 receptor (IL-2R), but not p75 IL-2R, in cultured H-RS cells and H-RS cells in tissues.

The authors studied the secretion of interleukin-2 (IL-2), the expression of interleukin-2 receptors (IL-2R; p55/Tac and p75), and the response to exogenous IL-2 by cultured Hodgkin's Reed-Sternberg cells (cell lines HDLM-1, HDLM-1d, and KM-H2) and T cells (H9, HuT78, HuT102, MOLT-4, and MT-2). All of these cells did not produce IL-2 or produced it in undetectable amounts, and their growth was not affected by the addition of anti-IL-2 or anti-IL-2R antibodies. This indicates that H-RS cells in long-term culture, as well as T cells, can grow independently of IL-2. The three H-RS cell lines, as well as two of the T-cell lines (HuT102 and MT-2), expressed Tac, whereas the other three T-cell lines were Tac negative. Expression of p75 was noted in the two Tac-positive T-cell lines, but not in cultured H-RS cells. The expression of Tac and p75 in HuT102 and MT-2 cells correlated well with their capacity to proliferate on treatment with exogenous IL-2. On IL-2 treatment, nucleic-acid uptake in Tac/p75-positive T cells increased approximately four- to sixfold, whereas the Tac/p75-negative T cells did not show increased proliferation. Unlike the T cells, the Tac-positive H-RS cells did not respond to IL-2. The lack of a proliferative response to IL-2 appears to be related to the absence of p75 in H-RS cells. A similar pattern (Tac positivity and p75 negativity) was noted in H-RS cells in lymph nodes involved by Hodgkin's disease. Thus the exogenous IL-2 released by surrounding T lymphocytes may not cause the proliferative activity of H-RS cells because of the lack of high-affinity IL-2 receptors in the latter cells. In contrast to H-RS cells in culture, H-RS cells in tissues were stained by a specific anti-IL-2 monoclonal antibody. This indicates that the expression of IL-2 or an IL-2-like substance by H-RS cells in tissues may be responsible, in part, for the great increase in the number of reactive T lymphocytes in tissues involved by Hodgkin's disease.

Blotting, Northern↗
PubMed1990

[Clinical study of awake fiberoptic nasotracheal intubation for difficult opening mouth patients].

The intubation technique for those surgical patients considered to be difficult intubation were classically managed by blind nasotracheal intubation, tracheostomy and so forth. These procedures are rather invasive and resulted in post-operative complications. 30 adult patients of ASA class II-III with difficulty in intubation were chosen to receive awake fiberoptic nasotracheal intubation. Our aim of study is to evaluate the change of blood pressure, heart rate and SaO2 of these patients at 4 stages: I) preanesthesia II) transtracheal local block III) during intubation IV) post-intubation. As a result, there were no significant difference in comparing the parameters among these 4 stages. Additionally, fiberoptic guiding provide a direct vision on the way of intubation, enhance the successful rate of difficult intubation and minimize further trauma and discomfort to the patients. Therefore fiberoptic intubation may suitable in patients with difficult intubation.

Adult↗
PubMed1990

Halothane-inhalation system for using atracurium in rats.

This report describes an inhalation anesthetic technique employed in rats. Polyethylene-glycol 400 (PEG 400) was first designed to combine with halothane to produce a slow-releasing system of vaporized halothane. This design provided adequate anesthetic levels for treating with atracurium, a new neuromuscular blocking agent. Furthermore, isoflurane was also used in this study to examine this inhalation system for treating with atracurium. The efficient concentrations of inhalated anesthetics for adequate anesthesia when combining with PEG were 0.15% and 0.1% for halothane and isoflurane, respectively. This safe efficient state of anesthesia was maintained throughout the experimental course for treating atracurium, and might be used in clinical trials.

Anesthesia, Inhalation↗
PubMed1990

[Propofol intravenous anesthesia for intra-arterial catheterization in cancer patients].

Thirty cancer patients scheduled for intra-arterial catheterization for chemotherapy were premedicated with pethidine 1 mg/kg atropine 0.807 mg/kg and prochlorperazine 5 mg intramuscularly. Anesthesia was induced with 2 mg/kg propofol and maintained with continuous infusion of propofol at a rate of 12 mg/kg/h. Patients breathed room-air spontaneously through the whole course of anesthesia. Anesthesia was induced with 2 mg/kg propofol in all patients, then maintained successfully by using a mean infusion rate of 12.13 +/- 0.43 mg/kg/h propofol. They lost consciousness within 29.60 +/- 5.50 second. Two minutes after induction, there were significantly decreased in systolic pressure, diastolic pressure, stroke volume and cardiac output but heart rate did not change significantly. Blood pressure and cardiac output remained stable but lower than pre-anesthetic values during the rest of the anesthetic course. Arterial blood gas analysis confirmed the respiratory depression. Two minutes after induction, there were significantly decreased in PaO2, SaO2 and pH were noted. PaCO2 was increased significantly. Recovery from the anesthesia was rapid and uneventful. The average time required for the patients to sustain eye-opening and to answer questions were 9.20 +/- 1.79 min and 10.73 +/- 1.87 min respectively after discontinuing propofol injection. Transient restlessness occurred in one patient. No other post-operative complications were noted.

Adult↗
PubMed1989

Synthesis of 3-deazaneplanocin A, a powerful inhibitor of S-adenosylhomocysteine hydrolase with potent and selective in vitro and in vivo antiviral activities.

The neplanocin A analogue 3-deazaneplanocin A (2b) has been synthesized. A direct SN2 displacement on the cyclopentenyl mesylate 3 by the sodium salt of 6-chloro-3-deazapurine afforded the desired regioisomer 4 as the major product. After deprotection, this material was converted to 3-deazaneplanocin A in two steps. X-ray crystallographic analysis confirmed the assigned structure. Consistent with its potent inhibition of S-adenosylhomocysteine hydrolase, 3-deazaneplanocin A displayed excellent antiviral activity in cell culture against vesicular stomatitis, parainfluenza type 3, yellow fever, and vaccinia viruses. Antiviral activity was also displayed in vivo against vaccinia virus by using a mouse tailpox assay. The significantly lower cytotoxicity of 3-deazaneplanocin A, relative to its parent compound neplanocin A, may be due to its lack of conversion to 5'-triphosphate and S-adenosylmethionine metabolites.

Adenosine↗