Molecular cloning and expression of Epstein-Barr virus antigens in the lambda gt11 expression vector: antibodies towards proteins from the BORF2 and BKRF4 reading frames in nasopharyngeal carcinoma patients

An easy way to clone and screen for Epstein-Barr virus antigens significant in the diagnosis of nasopharyngeal carcinoma (NPC) has been developed. Two proteins cloned and expressed as fusion proteins in lambda gt11 have been identified to be expressed from 661 bp of the BORF2 and from 500 bp of the BNKRF4 reading frames. Western blotting studies on these proteins using serum from 16 NPC and 16 normal healthy individuals showed that 15 NPC patients have either IgG or IgA antibodies towards either protein whereas only 2 normal individuals were positive. Hence, IgG and IgA antibodies towards these antigens are of diagnostic value for NPC.

Participation of endogenous neuropeptide Y in the suppression of baroreceptor reflex response by locus coeruleus in the rat

We evaluated the potential participation of endogenous brain neuropeptide Y (NPY) in the suppression of baroreceptor reflex (BRR) response by locus coeruleus (LC), using adult male Sprague-Dawley rats anesthetized with pentobarbital sodium (40 mg/kg, i.p.). Bilateral microinjection of an antiserum against NPY (1:20, 20 nl) into the caudal one-third level of the nucleus tractus solitarii (NTS), the terminal site for baroreceptor afferent fibers, significantly reversed the suppressive effect of electrical or chemical activation of the LC on the BRR response. Treatments with NPY (4.65 pmol, 20 nl), normal rabbit serum, aCSF and heat-inactivated NPY or NPY antiserum, on the other hand, were ineffective. The LC-promoted inhibition of the BRR response was also attenuated by the alpha 1-adrenoceptor antagonist prazosin (50 pmol, 20 nl), either microinjected alone or in combination with NPY antiserum into the bilateral NTS. Mathematical treatment of our data revealed that the depressive effect on the BRR response of NPY or NE released at the NTS following LC activation manifested different time-course and magnitude. The one by endogenous NPY maximized at 40 min and amounted to no more than 20% of, whereas that by NE peaked at 10 min and contributed no less than 30% to, the suppression. These results suggest that both endogenous NPY and NE may participate in the suppression of BRR response by the LC at the NTS.

Power spectral analysis of the electroencephalographic and hemodynamic correlates of propofol anesthesia in the rat: intravenous infusion

Based on the tail-flick response to noxious thermal stimuli, we determined in the present study that effective antinociception could be achieved in adult male Sprague-Dawley rats 15 min after intravenous infusion of propofol at 60 mg/kg/h. Simultaneous power spectral analysis of the electroencephalographic (EEG) and systemic arterial pressure signals further revealed a concomitant depression of the activity of all EEG frequency bands (delta, theta, alpha, beta), alongside hypotension, negative inotropic and chronotropic actions, and attenuated baroreceptor reflex and vasomotor activity. These effects were congruent with a plasma concentration of propofol in the arterial blood of 1.70 +/- 0.13 micrograms/ml, as determined by high-performance liquid chromatography.

Graft rejection by T cells not restricted by conventional major histocompatibility complex molecules

The appropriate crosses of mice lacking conventional major histocompatibility complex (MHC) class I or class II molecules generate single- and double-deficient offspring. These were used as donors for skin grafts across major plus minor, or just minor, histocompatibility differences. Surprisingly, in the two circumstances, there was a rapid rejection of grafts lacking both MHC class I and class II molecules. Rejection was mediated by thymically derived CD4+ T cells of the host. We provide evidence that these T cells recognize an unconventional ligand, capable of activating a pre-formed T cell compartment but incapable of positively selecting it. The existence of this unexpected rejection phenomenon should serve to caution those aiming to engineer "universal donor" cells by simply abrogating expression of MHC class I and class II molecules.

Participation of nucleus reticularis gigantocellularis in the antinociceptive effect of angiotensin III in the rat

We evaluated the participation of nucleus reticularis gigantocellularis (NRGC), a medullary nucleus that plays an important role in the regulation of nociceptive processes, in the antinociceptive effect of angiotensin III (AIII), a biologically active peptide of the renin-angiotensin system. Adult, male Sprague-Dawley rats anesthetized with pentobarbital sodium (40 mg/kg, i.p., with 10 mg/kg/h i.v. infusion supplement) were used. Bilateral, site-specific microinjection of AIII (80 or 160 pmol) into the NRGC produced a dose-related increase in the latency of tail-flick response to noxious thermal stimuli (50 degrees C hot water). Such an antinociceptive action of AIII was blocked by concomitant administration of the AIII receptor antagonist, Ile7-angiotensin III (Ile7-AIII, 10 nmol). At the neuronal level, microiontophoretic application of AIII suppressed, Ile7-AIII reversibly, the responsiveness of nociception-related neurons in the NRGC to tail-clamping. These results demonstrated that central AIII may elicit antinociception via a process that may at least take place at the NRGC.

Passive biophysical membrane properties of nucleus reticularis gigantocellularis neurons in brain slices from the rat

This study employed intracellular recording coupled with the current clamp technique to characterize the passive biophysical membrane properties of neurons in the nucleus reticularis gigantocellularis (NRGC) of brain slices from adult, male Sprague-Dawley rats. We found that NRGC neurons possessed highly depolarized transmembrane potentials (-22.9 +/- 0.6 mV, n = 189). The 29 NRGC neurons that received further evaluation showed that they could be separated into two clusters, with significantly different membrane input resistances (3.51 +/- 0.89 vs 77.50 +/- 8.82 M omega) and membrane time constants (0.56 +/- 0.05 vs 1.27 +/- 0.12 ms). These membrane properties, which resembled qualitatively those we observed previously in cats in vivo, will form the basis for further evaluation of the ionic mechanisms that may underlie the actions of pharmacologic agents on the NRGC neurons.

A monoclonal antibody with specificity to the HLA-DR1 and -DR51 antigens

A monoclonal antibody 137BL7 raised against purified DR1 protein was shown to bind specifically to 5/5 DR1, 18/18 DR2 cells and 0/23 non-DR1,2 cells by cell-EIA. Further analysis by FACS using HLA-transfectants revealed that 137BL7 also bound specifically to the DRB5 transfectants in addition to the expected DR1 transfectants. However, it did not bind to the DR2 (DR15) transfectants, showing that cross-reactivity with DR2 cells lies with the DRB5 (DR51) rather than the DRB1 gene product. A comparison of the HLA-DR amino acid sequences of DR1 and DR51 antigens revealed a common glutamic acid residue at position 96, which may form the putative binding epitope of this mAb.

Antagonization of fentanyl-induced muscular rigidity by denervation of the coerulospinal noradrenergic pathway in the rat

The present study examined the effect of denervating the coerulospinal noradrenergic pathway on the muscular rigidity elicited by fentanyl in Sprague-Dawley rats anesthetized with ketamine. We demonstrated that the dopamine-beta-hydroxylase-positive nerve terminals arborizing on spinal motoneurons that innervate the sacrococcygeus dorsi lateralis (SCDL) muscle were significantly eliminated by DSP4 treatment. Unilateral microinjection of fentanyl (2.5 micrograms/50 nl) into the locus coeruleus of these animals also failed to evoke discernible increase in the electromyographic activity recorded from the SCDL muscle. These results lend further support for our previous finding that the coerulospinal noradrenergic neurotransmission is critically involved in fentanyl-induced muscular rigidity.

Visualization of G(o)alpha subtype guanine nucleotide-binding regulatory protein in the medulla oblongata and pons of the rat

This study reports on the visualization of G(o) protein in the medulla oblongata and pons of Sprague-Dawley rats, using a commercially available selective polyclonal antiserum against a 39-kDa protein corresponding to the alpha subunit of G(o). Specific immunofluorescent-staining was widely distributed in neuropils and neuronal cell bodies but displayed regional heterogeneity. The immunoreactive product exhibited a punctate appearance and was most pronounced in the cell membrane and cytoplasm of the perikarya and proximal dendrites whereas the nucleus remained unstained. Positive immunoreactivity of G(o)alpha was present in nucleus reticularis gigantocellularis, nucleus reticularis paramedialis, nucleus tractus solitarii, nucleus nervi hypoglossi, nucleus raphé pallidus, locus coeruleus, nucleus tractus mesencephali nervi trigemini and nucleus cuneatus. These results provided anatomic evidence to support the participation of G(o) protein in both sensory and motor functions that originate from the medulla oblongata and pons of the rat.

Human leucocyte antigen DNA typing in Singaporean Chinese patients with Graves' disease

Human Leucocyte Antigen (HLA) A, B, C, DR, DQ and DP locus alleles in 35 Chinese patients with Graves' disease and 80 controls were typed for using serological and DNA polymerase chain reaction/sequence specific oligonucleotide (PCR/SSO) methods. B46 was found to be strongly associated with male patients (p = 0.0002; RR = 8.2, 95% confidence interval 2.1-32.2). In HLA class 1 alleles, besides B46, the frequencies of A2 and Cw1 were increased and A24 and B63 decreased in patients compared to controls. In HLA class 2 alleles, the frequencies of DRB1*1602, *0301, *1405, DRB5*02, DQB1*0502 were increased and DRB1*1501, DQB1*0301 decreased in patients.

Continuous, on-line, real-time spectral analysis of systemic arterial pressure signals

We present in this communication an algorithm that offers continuous, on-line, real-time analysis of the power spectrum (CORAPS) of systemic arterial pressure (SAP) signals. Based on direct fast Fourier transform of raw SAP signals into power spectral density, it is suitable for the delineation of acute SAP spectral changes over time after physiological or pharmacological perturbations. Thus it is an improvement over most current methods, which only generate the spectra off-line or from intermittent data. Furthermore, all executions can be accomplished economically with a general-purpose personal computer. We demonstrated and quantified vivid sequential alterations in the low-frequency components (< 3 Hz) of the SAP spectrum, which purportedly reflect the influence of vasomotor, baroreceptor, and respiratory activity on SAP during pentobarbital administration or transient hypertension. Three window options incorporated into the algorithm further improved the frequency or temporal resolution and discrimination of the spectral changes during abrupt hypertension or hypotension. Thus our CORAPS algorithm may be useful as an on-line monitor for acute hemodynamic changes.

Comparison of two different trauma assessment scores in predicting trauma outcome

We reviewed 1,455 trauma cases admitted through the Emergency Department of National Cheng Kung University Hospital from June 1988 to December 1991. Of these, 1,251 patients had Revised Trauma Scores (RTS) and 1,452 cases had Injury Severity Scores (ISS) available for analysis of final trauma outcome. Several statistical methods such as simple logistic regression, the contingency table approach, and stepwise logistic regression were adopted to obtain the critical regions of major trauma which satisfied the requirements for sensitivity and specificity with the largest probability of a correct classification. We found that RTS < or = 5.7 and ISS > or = 17 were the best critical regions for defining major trauma. These patients deserve more attention during prehospital and interhospital disposition. Moreover, RTS contributes more to the prediction of patient outcome than ISS, indicating the power of RTS at the time of field evaluation in predicting patients' survival probability. The ISS is calculated retrospectively and is of limited value in acute settings. Therefore, based on our trauma database, we recommended that the RTS be used as a triage tool to select severely ill patients. We also urge that a generalized trauma registry be established in order to validate its usefulness.

Power spectral analysis of the electroencephalographic and hemodynamic correlates of propofol anesthesia in the rat: intravenous bolus administration

Based on the tail-flick response to noxious thermal stimuli, we determined in the present study that the minimal effective antinociceptive dose of propofol in adult, male Sprague-Dawley rats, given in an intravenous bolus manner, was 10 mg/kg. Simultaneous power spectral analysis of the electroencephalographic (EEG) and systemic arterial pressure signals further revealed a concomitant transient suppression of the EEG activity, primarily in the theta and sigma bands, alongside minor hypotensive and negative inotropic and chronotropic actions, but with maintained vasomotor tone. These alterations followed a time course that paralleled the plasma concentration of propofol in the arterial blood, as detected by high-performance liquid chromatography.

Another view of the selective model of thymocyte selection

Thymocyte commitment to the CD4 helper versus CD8 cytotoxic lineage has not been satisfactorily established. Two models have been elaborated: one based on instruction, the other on selection. Most previous results support the instructive model, but our comparison of thymocyte differentiation in MHC class II-, class I- and double-deficient mice provides data challenging it. There exists a significant population of CD4 single positive cells in class II-deficient animals that is intermediate in maturity between CD4+CD8+ and end-stage CD4+CD8- thymocytes and is selected on class I molecules; an equivalent CD8+CD4- population occurs in class I-deficient animals. We propose a selective model entailing two TCR-MHC molecule engagements: the first provokes random down-modulation of either CD4 or CD8 and a degree of differentiation; the second, requiring participation of the appropriate coreceptor, permits end-stage differentiation.

Spinal cord localization of the motoneurons innervating the sacrococcygeus dorsi lateralis muscle and their noradrenergic nerve terminals in rats

We examined in the present study the spinal cord localization of motoneurons innervating the caudal portion of the sacrococcygeus dorsi lateralis (SCDL) muscle and their noradrenergic nerve terminals in Sprague-Dawley rats, using horseradish peroxidase (HRP) and dopamine-beta-hydroxylase (DBH) double-labeling techniques. Retrogradely HRP-labeled motoneurons innervating the caudal part of the SCDL muscle were located ipsilaterally in the ventromedial aspect of the ventral horn (lamina IX) in spinal segments of S2-S4. These cells were polygonal in shape, with an average soma diameter of 37.0 +/- 1.1 microns (mean +/- S.E.M., n = 95) and amounted to 33.6 +/- 5.7 (n = 7) in the horizontal plane. Of note was the presence of abundant DBH-positive nerve terminals arborizing on the soma and dendrites of HRP-labeled motoneurons. These results provided anatomical evidence to further support our previous findings that the coerulospinal noradrenergic neurotransmission is involved in the mediation of fentanyl-induced muscular rigidity.

Unsustained dipsogenic response to chronic central infusion of angiotensin-III in spontaneously hypertensive rats

We evaluated the chronic effect of angiotensin-III (AIII) in the promotion of drinking behavior in spontaneously hypertensive (SH) and normotensive Wistar-Kyoto (WKY) rats, using conscious, freely moving, male, adult animals that had been instrumented with an intracerebroventricular (icv) cannula connected to an osmotic mini-pump for 7-day infusion. Chronic icv infusion of AIII (5 or 10 pmol/min) elicited robust, dose-dependent, and Ile7-AIII (100 pmol/min; as specific antagonist)-reversible dipsogenesis in both SH and WKY rats, with higher water intake in the former strain. However, the drinking response in the SHRs exhibited a sharp drop after 3 days of AIII infusion, during which acute AIII (80 pmol, icv) challenges also failed to induce dipsogenesis. Chronic icv infusion of bestatin (150 pmol/min), an aminopeptidase-B inhibitor, did not by itself discernibly affect basal drinking. When combined with AIII (5 or 10 pmol/min), however, bestatin, respectively, suppressed and augmented the dipsogenic response of SH and WKY rats to the heptapeptide. These results suggest that chronic administration of AIII did not produce sustained drinking behavior in SHRs, possibly because of the development of early desensitization of the angiotensin receptors.

HLA and Singaporean Chinese myasthenia gravis

Chinese Singaporean myasthenia gravis (MG) patients are associated with three HLA haplotypes: Cw1 B46 DRB1*0901 DQB1*0303 DQA1*03, DRB1*14 DRB3*0202 DQB1*0503 DQA1*0101 and DRB1*1202 DRB3*0301 DQB1*0301 DQA1*0601. The B46 haplotype was associated with the total group of MG patients but in particular with those with younger onset, low antiacetylcholine receptor (anti-AchR) titres, with only ocular lesions and with normal thymuses. The DRB1*14 haplotype was associated with thymic hyperplasia, younger onset patients, with high anti-AchR titres and with generalised MG. The DRB1*1202 haplotype was associated with thymoma, older onset patients, ocular lesions, and mid to high anti-AchR titres.

Simultaneous, continuous, on-line and real-time spectral analysis of multiple physiologic signals by a personal-computer-based algorithm

We presented in this communication a computer algorithm that offers the advantage of simultaneous analysis of the power spectrum of multiple physiologic signals, including systemic arterial pressure, single-neuronal and electroencephalographic signals, on a continuous, on-line and real-time basis. It provided sensitive definition, discrimination and quantification (graphic and digital) of the various frequency components in the spectrum. There was also great flexibility in selecting the physiologic signal(s) to be analyzed, the choice of results of analysis to be displayed for each physiologic parameter and the alteration of sensitivity and baseline of each event channel. Furthermore, it included window options to improve the frequency or temporal resolution and discrimination of the spectral changes. Most importantly, all these desirable features can be accomplished economically with a general purpose personal computer.

Reappraisal of the biological role of epidermal growth factor receptor in transitional cell carcinoma

Retrospective immunohistochemical and flow cytometric DNA analyses were performed on 56 cases of transitional cell carcinoma (TCC) to examine the biologic implications of epidermal growth factor receptor (EGFR) expression. A total of 28 (50%) cases were reactive for EGFR immunostaining. The receptor expression increased from 41.7 to 56.3% with tumor stage. There was a significant association between EGFR expression and tumor stage (p < 0.0005), but not tumor grade. The flow DNA content and the Ki-67 proliferating index had no relation to the status of EGFR (p = 1, respectively). For those receptor-positive tumors (n = 28), there was a significant association (p < 0.0001) between receptor expression and tumor proliferation. Interestingly, the DNA content was not correlated with EGFR expression (p = 0.69). We support the possible role of EGFR in cell proliferation and the potential significance for tumor growth in TCCs. However, the biology of TCC in half the cases could not be explained by this mechanism. The interaction between EGFR and DNA ploidy status necessitates further evaluation.

Tonic suppression of baroreceptor reflex response by endogenous neuropeptide Y at the nucleus tractus solitarius of the rat

We evaluated the potential participation of endogenous brain neuropeptide Y (NPY) in central cardiovascular regulation, using adult male Sprague-Dawley rats anesthetized with pentobarbital sodium (40 mg/kg, i.p.). Bilateral microinjection of NPY (4.65 pmol) into the caudal one-third level of the nucleus tractus solitarius (NTS), the terminal site for baroreceptor afferent fibers, promoted a significant suppression of the baroreceptor reflex (BRR) response. The maximal inhibition occurred at 30-40 min postinjection, and amounted to -42.7 +/- 8.6% (mean +/- S.E.M., n = 9). The same treatment, however, only caused transient (approximately 5 min) hypotension and bradycardia. Blocking the endogenous NPY activity at the NTS with its antiserum appreciably enhanced the sensitivity of BRR response (+ 59.2 +/- 18.8%, mean +/- S.E.M., n = 6), but had no appreciable effect on systemic arterial pressure or heart rate. These results suggest that neurons that contain NPY may participate in central cardiovascular regulation by tonically suppressing the BRR response, possibly by exerting an influence on the baroreceptive neurons at the NTS.

Characterization of Mirabilis antiviral protein--a ribosome inactivating protein from Mirabilis jalapa L

A protein was purified from root tubers of Mirabilis jalapa to homogeneity by ion-exchange chromatography on CM-Sepharose CL-6B and FPLC on Mono-S column. The purified protein was confirmed to be Mirabilis antiviral protein (MAP). However, in addition to its antiviral property, the MAP was demonstrated to possess abortifacient activity in pregnant mice, inhibitory effect on cell-free protein synthesis and antiproliferative effect on tumor cells. As judged from its biological and physiochemical properties, MAP is a type I ribosome-inactivating protein.

Identification and cloning of a novel heterogeneous nuclear ribonucleoprotein C-like protein that functions as a transcriptional activator of the hepatitis B virus enhancer II

Liver specificity of hepatitis B virus (HBV) replication has been attributed to the action of its second enhancer (EII). We report here the characterization of EII and the subsequent isolation of a novel liver-specific DNA-binding protein which binds to and activates EII. The cDNA clone of the protein, designated E2BP, was isolated from a lambda gt11 expression library constructed from the hepatoma cell line HuH-6 which was screened with a binding site probe derived from EII. Sequence analysis of E2BP revealed 86.6% homology with a rat heterogeneous nuclear ribonucleoprotein C protein sequence, while conformational studies suggest a helix-loop-helix motif as a DNA-binding site. Cloned E2BP expressed in human fibroblasts by transient transfection displayed EII binding and activating characteristics similar to those of native E2BP in hepatocytes.