[Studies on function of vegetative nervous system in cardiopathic patients with heart-qi deficiency syndromes and heart-yin deficiency syndromes]

To explore the changes of the function of vegetative nervous system in the patients with the syndromes of Heart-Qi Deficiency (HQD) and Heart-Yin Deficiency (HYD), 53 cases of heart diseases were divided into HQD and HYD, the duration between heart beats, differences of blood pressure in the lying and standing position, and urine-catecholamine/24 hrs was determined separately, and compared with control group. The results showed that the duration between heart beats and heart rate in the lying position in those patients of HQD didn't manifest significant difference with control group. But in 78.9% of patients, the differences of heart rate in expiration/inspiration, surpassed 15 beats per minute, and the proportion of 30/15 was less than 1.03. Compared with control group, the difference was significant (P < 0.01). Meantime, the differences of heart rate of lying/standing position was less than 15 beats per minute, and the difference of blood pressure had an increasing tend in 47.4% of the cases. Those patients of HYD didn't show any difference in the above indexes. Urine-catecholamine/24 hrs in both of the two groups surpassed that of control group (P < 0.01). In short, this study showed that syndromes of HQD and HYD both displayed disturbed function of the vegetative nervous system, and their types and severities were correlated with the difference of Syndromes.

Agonistic actions of pergolide on firing activity of dopamine neurons in substantia nigra compacta area

AIM

To study the potency of pergolide as a D2 receptor agonist on the firing activity of substantia nigra compacta (SNC) dopamine (DA) neurons compared with that of bromocriptine and to determine whether pergolide has the nature of D1 receptor agonist in vivo.

METHODS

Extracellular single unit recording techniques.

RESULTS

Both pergolide and bromocriptine decreased the spontaneously firing rate of "sensitive" and "insensitive" DA cells. In regard of ID50 values, pergolide (11.9, 95% fiducial limits, 5.7-25.1 micrograms kg-1) was more potent than bromocriptine (7.8, 95% fiducial limits, 3.3-18.5 mg kg-1). The discharge inhibition of pergolide was attenuated following the injection of selective D2 receptor antagonist spiperone 0.25 mg kg-1 or selective D1 receptor antagonist Sch-23390 1-2 mg kg-1. However, the inhibition caused by bromocriptine was not always attenuated by spiperone.

CONCLUSION

Pergolide is 650 times more potent than bromocriptine at D2 receptors, and possesses D1 receptor agonist characteristics in vivo.

Technetium-99m N,N'-bis(2-mercapto-2-methylpropyl)-2-aminobenzylamine: technetium-99m complexes of a novel bis(aminoethanethiol) ligand

A new N2S2 ligand system, N,N'-bis(2-mercapto-2-methylpropyl)-2- aminobenzylamine, U-BAT, 1, containing uneven amine groups (two amine groups with different pKa values) for complexing [TcVO]3+, was prepared. The reaction of this novel ligand with [99mTc]pertechnetate, in the presence of stannous tartrate as the reducing agent, produces the neutral and lipid-soluble [99mTc]TcVO(U-BAT), TcS2C15H23N2O, 2. However, when the same reaction was carried out at a higher pH, 9-10, and with 30 min of heating (100 degrees C), a second neutral but more lipid-soluble complex, [99mTc]TcVO(OU-BAT), TcS2C15H21N2O, 3, was isolated. The X-ray crystallography data of the 99Tc complexes show square pyramidal coordination with N2S2 as the base and the Tc = O in the apical position. Compound 3 can be derived from 2 by an oxidation of the ligand to form an imine. After iv injection into rats, the neutral and lipid-soluble technetium-99m complexes showed significant brain uptake, 1.54 and 1.07% dose/organ at 2 min for [99mTc]TcVO(U-BAT) and TcVO(OU-BAT), respectively. The novel Tc chemistry of this new ligand system may provide a useful foundation for designing Tc complexes with a built-in redox mechanism.

Cytogenotoxicity of N-acetyl-S-(1/2-phenyl-2-hydroxyethyl)-cysteine (NAPEC) in cultured human blood lymphocytes

N-Acetyl-S-(1/2-phenyl-2-hydroxyethyl)-cysteine (NAPEC) is a cysteine conjugate derived from the glutathione conjugate of styrene oxide. The dose- and time-dependent effects of NAPEC on SCEs and cell kinetics were studied in cultured human blood lymphocyte in vitro. Different concentrations of NAPEC (0-1500 microM) were added into the lymphocyte cultures. After 36 h of exposure, both the induction of SCEs and cell-cycle delay were increased with increasing concentrations of NAPEC. When the lymphocyte cultures were exposed to 1000 microM NAPEC for 22, 36 and 72 h during a total of 72-h culture period, no significant differences in the induction of SCEs or cell-cycle delay were noticed due to 3 exposure times. These results suggest that NAPEC possesses the potential to induce SCEs and to inhibit cell-cycle progression and such potential seems to be independent of duration of exposure to NAPEC.

Ciliary neurotrophic factor is an endogenous pyrogen

Fever is initiated by the action of polypeptide cytokines called endogenous pyrogens, which are produced by the host during inflammation, trauma, or infection and which elevate the thermoregulatory set point in the hypothalamus. Ciliary neurotrophic factor (CNTF) supports the differentiation and survival of central and peripheral neurons. We describe the activity of CNTF as intrinsically pyrogenic in the rabbit. CNTF induced a monophasic fever which rose rapidly (within the first 12 min) following intravenous injection; CNTF fever was blocked by pretreatment with indomethacin. The fever induced by CNTF was not due to contaminating endotoxins. Increasing doses of CNTF resulted in prolongation of the fever, suggesting the subsequent induction of additional endogenous pyrogenic activity. After passive transfer of plasma obtained during CNTF-induced fever, endogenous pyrogen activity was not present in the circulation; CNTF also did not induce the endogenous pyrogens interleukin 1, tumor necrosis factor, or interleukin 6 in vitro. Nevertheless, a second endogenous pyrogen may originate within the central nervous system following the systemic injection of CNTF. Of the four endogenous pyrogens described to date (interleukin 1, tumor necrosis factor, interferon, and interleukin 6), CNTF, like interleukin 6, utilizes the cell-surface gp 130 signal-transduction apparatus.

Effects of different styrene metabolites on cytotoxicity, sister-chromatid exchanges and cell-cycle kinetics in human whole blood lymphocytes in vitro

5 metabolites of styrene were tested in vitro for their cytotoxic effects, induction of SCEs and changes in cell-cycle progression in cultured human blood lymphocytes. Fresh heparinized peripheral blood (0.3 ml) from normal volunteers was cultured for a total of 72 h in 5 ml of RPMI 1640 medium containing 10% fetal calf serum, 0.1% garamycine, 1% glutamine and 1% phytohaemagglutinin. Styrene-7,8-oxide (SO), styrene glycol (SG), phenylglyoxylic acid (PGA), S-[1,2-phenyl-2-hydroxyethyl]-glutathione (PEG) (a glutathione conjugate of styrene oxide), N-acetyl-S-[1,2-phenyl-2-hydroxyethyl]-cysteine (NAPEC) in dimethyl sulfoxide (DMSO) were injected into the cultures 36 h after initial culture, so that the exposure time for these metabolites was 36 h. The final concentration of SO was 100 microM and those of the other metabolites were 500 microM. 24 h before harvest, BrdU (10 micrograms/ml) was added into the cultures for assessing cytogenetic endpoints. SO showed significant induction of SCEs and cell-cycle delay as well as a significant decline of cell survival. The same phenomena, but of less magnitude, were also observed with NAPEC, a cysteine derivative of SO. On the other hand, SG, PGA and PEG failed to produce any significant changes of these endpoints compared to the control. Thus, the present results have demonstrated that, in addition to SO, NAPEC possesses some cytogenotoxic potential and hence, these two metabolites together could contribute to the genotoxicity of styrene in human blood lymphocytes.

[An investigation on the freshwater crab as the host of Paragonimus in Hunan province]

Through an investigation of the freshwater crabs in 39 counties of Hunan province, 20 species of fresh water crabs were found as the intermediate hosts of Paragonimus. They belong to three genus and two families, in which 10 are new species (including 4 new subspecies). Besides, the natural infection with lung fluke metacercariae was also observed in some of the fresh water crabs.

Cytogenetic effects of low-level exposure to toluene, xylene, and their mixture on human blood lymphocytes

The present study was undertaken to investigate, both in vitro and in vivo, the genotoxic potential of short-term low-level exposure to toluene, xylene, and their mixture, for which information is limited at the present time. Five adult healthy white men were exposed for 7 consecutive hours per day over 3 consecutive days to 50 ppm toluene and 40 ppm xylene either alone or in combination in a controlled exposure chamber. Such an exposure was repeated three times at intervals of 2 weeks. Blood samples were taken before and after the termination of such exposure. Three different cytogenetic end-points were evaluated using peripheral blood lymphocytes: number of sister chromatid exchanges (SCEs), cell cycle delay, and cell mortality. No significant effects on SCEs, cell cycle delay, and cell mortality were observed following such exposure to toluene or xylene or their mixture. Similarly, exposure of human blood lymphocytes in vitro to either toluene (0-2.5 mM) or xylene (0-2 mM) or their mixture for 72 h did not result in any significant cytogenetic effects at lower concentrations, while at higher concentrations, only cell mortality was found to be significantly affected. Thus our present study indicates that simultaneous exposure to low levels (within the admissible limits) of toluene, xylene, or their mixture for a short period does not pose any potential mutagenic threat to humans.

Effect of ocular chromatic aberration on monocular visual performance

This brief review outlines the theory of ocular chromatic aberration and describes the three primary forms in which the aberration appears: chromatic difference of focus, chromatic difference of magnification, and chromatic difference of position. Our central theme is that all three aspects of chromatic aberration have as their common basis the chromatic dispersion of light. The magnitude of each form of the aberration is related to the others by simple linear formulas in which a key parameter is the location of the pupil relative to the nodal point of the eye. The way in which retinal image quality is affected by chromatic aberration is described and we assess the impact of the aberration on visual performance.

Achromatizing the human eye

Ocular chromatic dispersion manifests itself as wavelength-dependent image planes, image sizes, and image positions, and it has been suggested that ocular chromatic aberration is the most important of the eye's optical aberrations. Most attempts to correct for the eye's chromatic aberration (achromatize the human eye) have concentrated on correcting the wavelength-dependent image planes or chromatic difference of refractive error (CDRx). There are two optical techniques that correct for CDRx (special achromatizing lenses and multiple channel display systems) by making the ocular image planes of all wavelengths coincident. A different approach simply avoids the effects of ocular CDRx by using small pupils which effectively make all images diffraction-limited irrespective of wavelength-dependent differences in image planes. Theoretical and experimental evidence shows that achromatizing lenses provide an accurate correction for CDRx. In spite of the pre-eminence of chromatic aberrations, and the effectiveness of the corrections, no obvious improvements in vision accompany correction. We show that loss of retinal image quality due to CDRx may be subthreshold (less than ocular depth of focus). We also show that achromatizing methods can introduce their own chromatic aberrations that can easily exceed those present in the uncorrected eye. The precise location of the eye with respect to the achromatizing device determines the amount of these additional aberrations. Therefore, in order to achromatize the eye effectively, careful control of eye position is essential.

Relation between the chromatic difference of refraction and the chromatic difference of magnification for the reduced eye

We provide a simple model for calculating the chromatic difference of magnification for the human eye. Spectral differences in image size are proportional to the eye's longitudinal chromatic aberration and the axial distance between the entrance pupil and nodal point. We verify that the model provides magnification estimates equal to previously published predictions, and we show the significant increase in this aberration produced by experimental use of artificial pupils.

Achromatizing the human eye: the problem of chromatic parallax

Attempts to correct the chromatic difference of focus of the human eye will introduce unwanted chromatic parallax if the eye is misaligned with the optical axis of the achromatizing system. Using geometrical optics, we show that the amount of parallax is approximately proportional to the amount of misalignment of the eye, with the constant of proportionality equal to the eye's chromatic difference of refractive error. This prediction was confirmed by the experimental determination of chromatic parallax for two commercially available achromatizing lenses. On the basis of these results, we calculated that anticipated improvements in the polychromatic modulation transfer function of the eye offered by achromatizing lenses will be canceled by approximately 0.4 mm of the misalignment between the lens and the eye. Our prediction that further misalignment would severely reduce image quality of the achromatized eye was verified by psychophysical measurements of contrast sensitivity.

Interocular differences in transverse chromatic aberration determine chromostereopsis for small pupils

Chromostereopsis has been attributed previously to interocular differences in foveal transverse chromatic aberration (TCA). We tested this hypothesis by measuring chromostereopsis as a function of the separation of small artificial pupils. We also measured the monocular transverse chromatic aberration under the same conditions. Our results show that chromostereopsis with small pupils can be precisely accounted for by the interocular difference in monocular transverse chromatic aberration. This relationship is closely predicted by a simple water eye model.

Isolation and characterization of a molecular cDNA clone of a human mRNA from interferon-treated cells encoding nucleolar protein B23, numatrin

A cDNA clone encoding human nucleolar phosphoprotein B23, numatrin, was isolated from a library prepared with mRNA from human U cells. The complete nucleotide sequence was determined; it revealed a single open reading frame of 294 amino acids that included four in-frame AUG codons as potential sites of translation initiation. Comparison of the human B23 nucleotide sequence with the rat and mouse B23 sequences revealed 91% homology (hum:rat, and hum:mus) in the coding region; the predicted B23 proteins displayed 94% amino acid identity. Northern gel blot analysis revealed a single B23 mRNA species of approximately 1.5 kb. The level of B23 mRNA in U cells was not detectably altered by treatment with either alpha or gamma interferon. Southern gel blot analysis revealed polymorphism within the human B23 gene structure, and suggested the presence of multiple B23 genes and/or extensive splicing of B23 RNA transcripts.