Interferon-gamma-induced factor binding to the interleukin-4-responsive element of CD23b promoter in human tonsillar mononuclear cells: role in transient up-regulation of the interleukin-4-induced CD23b mRNA

Stimulation of human tonsillar mononuclear cells with interleukin-4 (IL-4) and interferon-gamma (IFN-gamma) rapidly induced the activation of distinct nuclear factors with different mobilities, both of which bind the IL-4 response element (IL-4RE) of CD23b promoter as examined by electrophoretic mobility shift assays (EMSA). Co-treatment of IL-4 and IFN-gamma induced, in addition to the two distinct complexes, a new complex with an intermediate mobility. The IL-4-induced complex reacted with anti-STAT (signal transducers and activators of transcription) 6, resulting in a supershift whereas the formation of the IFN-gamma-induced complex was inhibited by anti-STAT 1. The intermediate complex appeared to react with both anti-STAT 6 and anti-STAT 1. Although IFN-gamma alone did not induce CD23 mRNA transcription, Northern blot analysis revealed a transient up-regulation of the IL-4-induced CD23 mRNA by IFN-gamma within 2 h of IFN-gamma treatment in these tonsillar cells. The results suggest that the IL-4RE of the IL-4-inducible gene can accommodate both IL-4- and IFN-gamma-activated factors, such as STAT 6 and STAT 1, either in homodimeric or heterodimeric forms and the binding of these different proteins to the respective promoter may play a potential regulatory role in the IL-4-inducible gene expression.

Identification and activation mechanism of the interleukin-4-induced nuclear factor binding to the CD23(b) promoter in human B lymphocytes

CD23 is a B cell activation antigen involved in B cell proliferation and production of IgE, of which two isoforms are known. While CD23(a) is constitutively expressed in B cells, the expression of CD23(b) is specifically induced by interleukin-4 (IL-4) or selected mitogenic stimuli. We have previously shown that CD23(b) is a primary response gene rapidly activated by IL-4 in resting human B cells. We now report the identification of a nuclear factor binding to the IL-4-response element (IL-4RE) in CD23(b) promoter in purified human tonsillar B cells. Activation of this factor, named NF-IL-4/CD23, occurred within 5 min after IL-4 treatment in a cycloheximide-insensitive manner. The activation was sensitive to phosphatases and inhibitors of protein tyrosine kinases, but it was not sensitive to inhibitors of protein kinase C. This behavior, in fact, closely correlates with the IL-4-induced activation mechanism of CD23 gene expression. In transformed B cell line Raji, where the IL-4-induced CD23 mRNA expression was hardly detected, no activation of NF-IL-4/CD23 was noted. The activation was also observed that although a sequence highly homologous to the IL-4RE of the CD23(b) promoter is present in the CD23(a) promoter, the IL-4-induced factor did not bind the sequence. These results strongly suggest that NF-IL-4/CD23 acts as an IL-4 signal transducer leading to CD23(b) gene activation in human B cells. Further characterization of this factor is now in progress, including comparison with STAT6, recently shown to be involved in IL-4 signal transduction and transcriptional activation.

High-performance fiber-optic temperature sensor using low-coherence interferometry

A temperature-sensor system based on low-coherence interferometry with a fiber Mach-Zehnder interferometer as a phase modulator was implemented. A measurement range of 20 to 800 degrees C with a resolution of 0.025 degrees C (corresponding to 0.0004 fringe) was achieved with a 1-mm-long fiber Fabry-Perot interferometer as the sensing element.

Luteinizing hormone-releasing hormone gene expression differs in young and middle-aged females on the day of a steroid-induced LH surge

LHRH mRNA levels were examined in young and middle-aged female rats at 4 times (10:00 h, 14:00 h, 18:00 h and 20:00 h) on the day of a steroid-induced LH surge by in situ hybridization with a digoxigenin-labeled riboprobe. Young, but not middle-aged females, exhibited dynamic temporal changes in the number of LHRH mRNA positive neurons detected in the organum vasculosum of the lamina terminalis-preoptic area (OVLT-POA) continuum. Specifically, fewer LHRH mRNA positive neurons were detected at 18:00 h compared with the number detected at 14:00 h and 20:00 h (P < 0.01) in the OVLT-POA of young females. All LHRH mRNA positive neurons present in 4 anatomically matched sections through the rostral POA of young and middle-aged animals were digitized for detailed computer-assisted analysis of the hybridization reaction product. The mean hybridization area (P < 0.00025) and integrated optical density per cell (P < 0.006) were reduced in middle-aged compared to young females consistent with a relative age-related decline in LHRH mRNA levels. Moreover, an age-related reduction in cellular and/or regional hybridization area was noted at each of the time points examined (P < 0.05-P < 0.001). These data confirm earlier reports of dynamic changes in LHRH mRNA levels on the day of an LH surge. Furthermore, they support a role for age-related alterations in LHRH gene expression in the disruption of regular estrous cyclicity in middle-aged females.

Effect of supraspinal antisense oligodeoxynucleotide treatment on delta-opioid receptor mRNA levels in mice

Studies in vivo demonstrate that antisense oligodeoxynucleotide (ODN) treatment specifically reduces the functions mediated by numerous central nervous system (CNS) receptors, including opioid receptors. However, the effects of antisense ODN on the opioid receptor mRNA target, itself are rarely examined. In the present study, the effect of supraspinal antisense ODN administration on delta-opioid receptor (DOR) mRNA levels in selected CNS regions, was investigated in mice. ODN targeting a 20-nucleotide sequence of the DOR mRNA transcript was administered by intracerebroventricular (i.c.v.) injection twice daily for 3 days. First, to confirm that antisense ODN treatment decreases DOR function in this system, antinociception produced by DOR-selective agonist [D-Ala2]deltorphin II was assessed on day 4. A 2-fold reduction in [D-Ala2]deltorphin II potency was revealed in antisense ODN-treated mice compared to mice receiving control treatments. DOR mRNA levels in selected CNS regions which either mediate antinociception; medial thalamus (MThal), periaqueductal gray (PAG), frontal cortex (FCtx) and spinal cord (SpC) or exhibit relatively high levels of DOR mRNA; nucleus accumbens (Acb) and caudate-putamen (CPu) were then quantitated by solution hybridization. Levels of DOR mRNA in antisense ODN-treated mice were not different from levels in mice treated with saline vehicle, which ranged from 0.07 pg/microg total RNA in MThal and PAG to 0.26 pg/microg total RNA in CPu. These results are both consistent with previous reports that antisense oligodeoxynucleotide (ODN) treatment down-regulates DOR protein in vivo and indicate that this down-regulation is not associated with altered DOR mRNA levels.

Blockade of morphine supersensitivity by an antisense oligodeoxynucleotide targeting the delta opioid receptor (DOR-1)

An antisense oligodeoxynucleotide (ODN) targeting 20 bases of the coding sequence of the cloned delta opioid receptor (DOR-1), a mismatched ODN (different from the antisense ODN at 4 bases) or saline was administered to 3 groups of CD-1 mice implanted with naltrexone pellets (7.5 mg) for 7 days. Morphine supersensitivity (i.e., increased potency as defined by decreased morphine ED50 values) was observed 24 h after pellet removal (day 8) in mice treated with saline or mismatch ODN, but not in antisense ODN treated mice. Antisense ODN alone had no effect on basal nociceptive thresholds or morphine analgesia but reduced the analgesic potency of the delta, opioid agonist [D-Ala2]deltorphin II. These data suggest that the delta2 opioid receptor system participates in the adaptive changes contributing to increased morphine potency following chronic naltrexone treatment.

An antisense oligodeoxynucleotide to the delta opioid receptor (DOR-1) inhibits morphine tolerance and acute dependence in mice

Pharmacological data from several laboratories support a modulatory role for the delta opioid receptor in morphine analgesia, tolerance, and physical dependence. We examined the role of the delta opioid receptor in these processes using an in vivo antisense strategy in mice. Intracerebroventricular administration of a 20mer antisense or a mismatch control oligodeoxynucleotide (ODN) targeting the mRNA of the cloned delta opioid receptor (DOR-1) for 3 days did not affect baseline nociceptive thresholds or morphine analgesia compared to untreated or saline-treated mice. However, dose-response studies indicate that the induction of morphine tolerance following 3 days of chronic morphine administration was blocked in antisense but not mismatch ODN or saline-treated mice. Antisense ODN treatment also blocked the development of acute morphine dependence, whereas similar protection was not afforded to mice treated with saline or mismatch ODN. This study demonstrates the relevance of the cloned DOR-1 in morphine tolerance and dependence and provides new evidence for a modulatory role of the delta opioid receptor using this novel approach.

Reconstructions of populations of luteinizing hormone releasing hormone neurons in young and middle-aged rats reveal progressive increases in subgroups expressing Fos protein on proestrus and age-related deficits

Fos expression has been used as a marker of activation of neuroendocrine cells including LHRH neurons. In this study, Fos protein was localized within LHRH neurons in young and middle-aged rats to trace the temporal and spatial pattern of LHRH neuronal activation associated with the preovulatory LH surge. Animals were killed during the late morning, afternoon, and evening of proestrus. Dual immunocytochemical protocols localized LHRH and LHRH/Fos neurons, and computer-assisted methods were used to reconstruct forebrain populations of single- and double-labeled LHRH neurons. Although a significant increase in the number of LHRH/Fos neurons was noted by evening in both age groups, a greater increase was observed in young (12% in morning, 28% in afternoon, and 62% by evening) compared with aging females (5% in morning, 10% in afternoon, and 40% by evening). Reconstructions of LHRH and LHRH/Fos neurons revealed time- and age-dependent differences in Fos expression within LHRH neurons. In young females, LHRH/Fos neurons were restricted to central regions of the population of LHRH neurons on the morning of proestrus. By evening, Fos expression was also observed in more peripheral and caudal LHRH neurons. In middle-aged females, Fos expression was restricted to ventral subgroups of LHRH neurons on the afternoon of proestrus. By evening, more LHRH neurons contained Fos protein, however, few were located in the dorsal aspect of the population. These data trace the progressive increase in activation of LHRH neurons during the preovulatory LH surge in young females and reveal deficits in this pattern of activation by middle age.

Multiplexed interferometric fiber-optic sensors with digital signal processing

A microcontroller-based digital signal processing system developed for use with fiber-optic sensors for measuring pressure in internal combustion engines is described. A single distributed feedback laser source provides optical power for four interferometric sensors. The laser current is repetitively modulated so that its optical frequency is nearly a linear function of time over most of a cycle. The interferometer phase shift is proportional to the elapsed time from the initiation of a sawtooth until the sensor output signal level crosses a threshold value proportional to the laser output power. This elapsed time, assumed to vary linearly with the combustion chamber pressure, is determined by the use of a digital timer-counter. The system has been used with fiber Fabry-Perot interferometer transducers for in-cylinder pressure measurement on a four-cylinder gasoline-powered engine.

A reduced proportion of luteinizing hormone (LH)-releasing hormone neurons express Fos protein during the preovulatory or steroid-induced LH surge in middle-aged rats

Results of previous studies suggest that altered patterns of LHRH neurosecretion contribute to attenuated LH surges and the eventual cessation of ovulation in aging female rats. The present study compared evidence of LHRH neuronal activation in conjunction with the preovulatory and steroid-induced LH surge in young and middle-aged animals to determine whether age-related alterations could be detected. Double immunocytochemical protocols were used to colocalize LHRH and the protein product of the proto-oncogene c-fos, which increases within the nucleus of LHRH neurons in association with spontaneous or induced LH surges. The mean proportion of LHRH neurons containing immunoreactive Fos was higher in the brains of young compared to middle-aged females in association with both the preovulatory (p < 0.01) and the steroid-induced LH surge (p < 0.001). The time course of activation of LHRH neurons was delayed in the brains of aging females, and the proportion of double-labeled LHRH neurons remained elevated longer in the brains of young compared to middle-aged steroid-treated females. Moreover, regional differences in LHRH neuronal activation were observed both within and between age groups. The data presented suggest that reduced LHRH neuronal activation may contribute to the attenuation and eventual loss of preovulatory LH surges in middle-aged female rats.

Electrical injury--clinical report of 67 cases

We have reviewed 67 patients of electrical burns treated at Linkou Burn Center of Chang Gung Memorial Hospital from January 1988 to April 1992. There were 2086 acute burn admissions during this period with the proportion of electrical injuries being 3.2%. Their age ranged from 13 to 68 years, with 61% in the age group of 20 to 40 years. Sixty-two (92.5%) of our patients were males. Over 60% of these injuries were work-related. The proportion of high voltage electrical injuries was over 60% in our series. All deceased patients and those patients with major complications were in the high voltage electrical injuries group. Low voltage injuries did not leave any major sequelae. In a mean follow-up of 2 years, 83% of our patients could return to the previous job or change to another work. The overall mortality was 6%.

Fiber-optic pressure sensors for internal combustion engines

Two designs incorporating embedded fiber Fabry-Perot interferometers as strain gauges were used for monitoring gas pressure in internal combustion engines. Measurements on a Diesel engine, a gasoline-fueled engine, and a natural-gas engine are reported.

Mechanism of interferon-gamma down-regulation of the interleukin 4-induced CD23/Fc epsilon RII expression in human B cells: post-transcriptional modulation by interferon-gamma

It has been reported that the interleukin 4 (IL-4) specific induction of cell surface CD23 (Fc epsilon RII) is down-regulated by interferon-gamma (IFN-gamma) in monocytes and B cells. However, the molecular level at which the inhibition occurs seems to vary depending on the cell types. In normal human B cells, IFN-gamma inhibits the IL-4 induced de novo synthesis of CD23 at the level of gene expression. Analysis of inhibition kinetics suggested a rapid signal transmission by IFN-gamma. Yet the inhibitory action of IFN-gamma on CD23 mRNA accumulation appeared as a secondary response requiring a new protein synthesis. Through nuclear run-on transcription and mRNA stability studies, we further demonstrate that the IL-4 induced CD23 gene expression is down-regulated by IFN-gamma mainly at post-transcriptional levels by decreasing mRNA stability.

Interleukin-4 signals regulating CD23 gene expression in human B cells: protein kinase C-independent signaling pathways

Signal transduction by IL-4 leading to the activation of CD23(Fc epsilon RII) gene expression using human tonsillar B cells was studied. IL-4 stimulated CD23 mRNA transcription within hours (1-4 hr) which preceded the later induction of cell surface CD23. The induction of CD23 gene transcription by IL-4 was not adversely affected by cycloheximide, suggesting that post-translational modifications are accounted for the gene activation. PKC activators (PMA, diacylglycerol, indolactam) were effective inducers of CD23 gene expression, whereas calcium ionophores were not. PMA and IL-4 also displayed similar induction kinetics for CD23 mRNA. However, the signaling pathways utilized by the two agents appear distinct as shown by (1) cotreatment of IL-4 and PMA caused CD23 gene expression over the maximum level inducible by each agent alone and (2) unlike the PMA-induced CD23 expression, the IL-4-induced expression was not affected by PKC inhibitors. These results strongly suggest that IL-4 signals leading to CD23 gene activation are mediated via a PKC-independent pathway. A possible role of tyrosine kinases in the regulation of CD23 expression is discussed.

Studies on the role of interleukin-4 and Fc epsilon RII in the pathogenesis of minimal change nephrotic syndrome

Childhood minimal change nephrotic syndrome (MCNS) has often been associated with allergic symptoms such as urticaria, bronchial asthma, atopic dermatitis, allergic rhinitis and elevated IgE levels and referred to involve immune dysfunction. Fc epsilon RII is known to be involved in IgE production and response. Interleukin-4 is being recognized as a major cytokine up-regulating IgE production. Hence the present study is aimed at investigating the role of interleukin-4 and Fc epsilon RII in the pathogenesis of MCNS. IgE was measured by ELISA. Fc epsilon RII was analyzed by fluorescence activated cell scanner (FAC-scan) by double antibody staining with anti Leu16-FITC and anti Leu20-PE. Soluble IgE receptor was measured by ELISA using anti CD23 antibody (3-5-14). Interleukin-4 activities were measured by CD23 expression on purified human tonsillar B cells. Serum IgE levels were significantly higher in MCNS (1,507 +/- 680 IU/dl) than in normal controls (123 +/- 99.2 IU/dl). A significantly higher expression of membrane Fc epsilon RII was noted for MCNS (41 +/- 12%) than that in normal controls (18 +/- 6.2%) (p < 0.001). Soluble CD23 levels were also significantly higher in MCNS (198 +/- 39.3%) than in normal controls (153 +/- 13.4) (p < 0.01). Interleukin-4 activity in sera of MCNS (12U/ml) was also significantly higher than normal controls (4.5U/ml). These results indicate that increased production of Fc epsilon RII and interleukin-4 may play an important role in the pathogenesis of MCNS.

Interleukin-6 is released in the cutaneous response to allergen challenge in atopic individuals

The mechanisms responsible for cutaneous response to antigen are complex. Interleukin-1 (IL-1) and interleukin-6 (IL-6) are proinflammatory cytokines that share many properties. Previous studies with a blister-chamber model have demonstrated IL-1 to be produced in the cutaneous response to antigen. Since IL-2 production by activated T cells and IL-6 production by macrophages are both stimulated by IL-1, we hypothesized that IL-2 and IL-6 may be involved in the cutaneous late-phase response (LPR) to antigen. We examined antigen-challenged sites for IL-2 immunoreactivity (ELISA) but found no difference between antigen- and diluent-challenged skin sites (N = 4). Since IL-2 has been demonstrated to be produced in response to IL-1 and IL-1 activity has been demonstrated to be greatest between hours 10 and 12, we speculated that IL-2 might not be detected until after hour 12. We were unable to demonstrate any increase in IL-2 production, even by extending our studies to 24 hours in two subjects. Antigen-challenged, skin blister-chamber fluids from atopic subjects demonstrated the appearance of IL-6 (ELISA) in pooled samples representing hours 1 1/2, 3 1/2, 5 1/2, and 7, but not at diluent control sites (p less than 0.05; N = 6). IL-6 reached a median peak of 0.66 ng/ml at 3 1/2 hours. Median levels of IL-6 fell to baseline at 8 hours, followed by a second peak of 0.25 ng/ml at hour 10. Three distinct patterns of IL-6 release were noted: early release of IL-6 followed by a sustained slower rise that peaked at hour 9 before declining to baseline levels at 12 hours, early release of IL-6 followed by a fall to baseline levels at hours 7 to 9 with a second smaller peak at hours 9 to 11, and isolated early release of IL-6. Early IL-6 production correlated with late histamine production (R = 0.801; p = 0.06), and late IL-6 production correlated with eosinophil influx (R = 0.813; p = 0.05). The area of the LPR at skin test sites correlated with early IL-6 peak levels (R = 0.977; p = 0.004) and with total early IL-6 production (R = 0.885; p = 0.05), but not with late IL-6 production.(ABSTRACT TRUNCATED AT 400 WORDS)

Metal-embedded fiber-optic Fabry-Perot sensors

The sensing of temperature and of ultrasonic pressure with fiber-optic Fabry-Perot interferometers embedded in aluminum is demonstrated. The metal parts are cast in air by using graphite molds. Breakage of the fibers at the air-metal interface during the casting process is avoided through the use of stainless-steel stress-relief tubes. The optical phase in an embedded interferometer is found to be 2.9 times more sensitive to temperature change than for the same interferometer in air, in good agreement with model calculations. An embedded interferometer has also been used to detect ultrasonic waves over the frequency range of 0.1-8 MHz.

Misoprostol does not alter the pharmacokinetics of propranolol

Twelve healthy volunteers took part in a randomised, double-blind, balanced, cross-over study to investigate the effect of misoprostol on the pharmacokinetics of propranolol. The subjects took propranolol 80 mg twice daily by mouth plus either misoprostol 400 micrograms twice daily or placebo by mouth for 14.5 days, followed by a 2-week washout period, followed by the alternate treatment for 14.5 days. Misoprostol had no significant effect on the t/2, Cmax or AUC of propranolol either after a single dose or at steady state.

Exact solutions to the multiregion time-dependent bioheat equation. II: Numerical evaluation of the solutions

Analytic solutions to the time-dependent multiregion bioheat equation are evaluated numerically for cartesian and spherical models. Principle and alternate branch contributions to the solutions are examined. The calculations include a parametric investigation and analyses of temperature behaviour in idealised upper thigh and tumour models.

Exact solutions to the multiregion time-dependent bioheat equation. I: Solution development

Exact solutions are obtained to the classical time-dependent linear bioheat equation in one-dimensional multiregion cartesian and spherical geometries with temperature-invariant physiological parameters. These solutions enable the study of transient temperature behaviour in an arbitrary number of coupled physiologically distinct regions.

A double-blind crossover study to compare lysine acetyl salicylate (Aspergesic) with ibuprofen in the treatment of rheumatoid arthritis

Lysine acetyl salicylate [1.8 g t.d.s. (Aspergesic 1,000 sachet)] has been compared to 400-mg ibuprofen tablets t.d.s. in a randomized double-blind trial in patients with rheumatoid arthritis using double-dummy technique. Both drugs proved effective in relieving symptoms. Three patients experienced drug-related side-effects with Aspergesic, and one patient with ibuprofen, that necessitated early discontinuation of treatment. Aspergesic was associated with a greater number of haemoglobin values falling below the normal range than ibuprofen. At the end of the study, eight out of 10 patients who expressed a preference selected Aspergesic for improving mobility whilst 15/24 selected Aspergesic for improving pain.

Embedded fiber-optic Fabry-Perot ultrasound sensor

A fiber-optic ultrasound sensor is presented. The sensor consists of a continuous length of single-mode optical fiber with a built-in Fabry-Perot interferometer. The acoustic pressure produces changes in the index of refraction along the interferometer cavity through the strain-optic effect, thus modulating the reflected power of the light propagating in the fiber. The dielectric internal mirrors that form the interferometer are fabricated by joining a fiber coating with a TiO(2) film at one end to an uncoated fiber by electric arc fusion splicing. Experimental results have been obtained for sensors embedded in plastic and graphite composite materials, using ultrasound waves in the range from 100 kHz to 5 MHz. Values for the optical phase shift amplitude as large as 0.5 rad were obtained at an acoustic frequency of 200 kHz for a 1.1-cm-long interferometer embedded in plastic.

Optical-fiber Fabry-Perot embedded sensor

A reflectively monitored optical-fiber Fabry-Perot interferometer was embedded in a graphite-epoxy composite material. Its performance as a temperature sensor was demonstrated from 20 to 200 degrees C. The change in relative phase shift with temperature, Deltaø/øDeltaT, was measured to be 8.0 x 10(-6)/ degrees C for this embedded sensor. This value is 4% lower than for one employing a similar fiber in an air ambient. A thermal expansion coefficient for the composite material in the direction of the fiber axis is estimated from these data to be 2.1 x 10(-7)/ degrees C.

Fiber optic application for thermal switching in vanadium dioxide films

Large thermally induced changes in the end-interface reflectance and transmittance of silica fibers coated with vanadium dioxide films have been observed.

Misoprostol reduces indomethacin-induced changes in human small intestinal permeability

This study examined whether indomethacin-induced increases in small intestinal permeability in man are prevented by concomitant administration of a prostaglandin analog (misoprostol). Twelve male volunteers were tested as baseline, following misoprostol alone (200 micrograms, at -16, -12, -8.5, -4, -1.5, and +4 hr); following indomethacin alone (75 mg, at -8; 50 mg, -1 hr); and following coadministration of misoprostol and indomethacin as specified above. A 100-ml test solution containing 3-O-methyl glucose (0.2 g), D-xylose (0.5 g), L-rhamnose (1.0 g), and [51Cr]EDTA (100 microCi) was ingested at 8 AM, and a 5-hr collection made for marker analysis to assess active and passive carrier-mediated transport and trans- and intercellular permeation, respectively. Indomethacin increased the permeation of [51Cr]EDTA selectively, and this increase was significantly reduced by the coadministration of misoprostol. These changes were mirrored by changes in [51Cr]EDTA-L-rhamnose urine excretion ratios, which indicates that paracellular permeability was specifically altered. This study supports the suggestion that NSAIDs alter intestinal permeability by a mechanism involving reduced prostaglandin synthesis and indicates that coadministration of misoprostol with NSAIDs may reduce the frequency and severity of NSAID-induced small intestinal inflammation.

Performance of a fiber-optic temperature sensor from -200 to 1050 degrees C

A reflectively monitored Fabry-Perot temperature sensor is characterized over a 1250 degrees C temperature range. Dielectric mirrors for the interferometer are incorporated into a continuous length of single-mode fiber by a fusionsplicing technique. The change in optical phase per unit temperature is nearly constant above room temperature but decreases at lower temperatures. Phase-shift data for the germania-doped silica fiber used in these experiments are compared with calculations based on previously reported information on the temperature dependence of refractive index and length in bulk fused silica.

Quantitative analysis of a polysulfated xylan (SP54) in urine using gas-liquid chromatography

A sensitive analytical method for the quantitation of a polysulfated xylan (SP54) in urine has been developed. SP54 and urinary glycosaminoglycans have been isolated from urine using cetylpyridinium chloride. This method removes all glycosaminoglycans with molecular weights less than 3000 Da. Following isolation, SP54 and urinary glycosaminoglycans have been selectively hydrolyzed under conditions (0.5 M HCl/105 degrees C/30 min) which produce an efficient yield of xylose from SP54 but not from the glycosaminoglycans. Xylose derived from SP54 has subsequently been determined using gas-liquid chromatography. Levels of SP54 down to 10 micrograms/ml have been determined using this technique.

Arterial embolism: a 44 year perspective

Forty-four years of experience with arterial embolism is reviewed. Patients presenting with this problem are increasingly older, more frequently female, and usually have atherosclerotic coronary artery disease. Atrial fibrillation is found in a high percentage of these patients. Mortality after embolism is decreasing but remains high (25 percent). Limb salvage is usually achieved (87 percent) but has improved little since the balloon embolectomy catheter became available. Prompt treatment, careful patient selection for operation, and anticoagulation remain the keys to successful outcome in the management of patients with arterial embolism.

Cylindroid lamella-particle complexes in lymphoma cells by northern pike (Esox lucius)

Cells of the malignant lymphoma of northern pike of Canada contained cylindrical structures with central cores of cytoplasmic elements and walls composed of lamellae in a spiral arrangement, separated by ribosome-like particles or by membranes. These cylindroids were similar, if not identical, to structures in the cells of certain human lymphomas and leukemias. In cross and longitudinal sections, the lamellae showed a pattern of light and dark bands resulting in an approximately 95 A-period that has not been described in the human cylindroids.