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J X Zhao

Publications and source records attributed to J X Zhao.

At least 19 recordsLinked to original sources
PubMed2001

[Experimental study on effect of fuzheng yiliu decoction on tumor cell cycle and telomerease].

OBJECTIVE: To study the mechanism of anti-tumor effect of Fuzheng Yiliu Decoction (FZYLD). METHODS: S180 neoplasm strain was inoculated in Kunming mice to establish model of S180 solid tumor. The model animals were treated with FZYLD by gastrogavage, the cell cycle of tumor were checked up by flow cytometer and the telomerease kit was used to test telomerease activity. RESULTS: The stage G0/1 ratio of tumor cells in model animals treated with FZYLD increased, while cells of S stage decreased, with telomerease activity inhibited. These changes were different significantly from those in the model animals treated with normal saline (P < 0.001). CONCLUSION: FZYLD could block the tumor cell proliferation procedure and inhibit the DNA synthesis and duplication in tumor cell. And the suppression of telomerease activity might be one of the mechanisms affecting the tumor cell proliferation cycle.

Animals↗
PubMed2000

Tropospheric sulfate aerosol formation via ion-ion recombination.

We propose a source of aerosols in the lower atmosphere associated with the creation, growth, and recombination of ubiquitous cosmogenically generated ions. This particle source should be favorable in the relatively clean, stable marine boundary layer, providing a uniform, continuous fine particle generator in the presence of dimethylsulfide emissions. Through this mechanism, new sulfate aerosols can be formed at sulfuric acid vapor partial pressures well below the supersaturations required for homogeneous binary nucleation of sulfuric acid/water solutions, which is consistent with numerous observations of new particle formation under sub-saturated conditions. The evolving aerosols in turn control the acid vapor concentration and thus modulate the sizes of the precursor ions and the rate of new particle formation. A simple model representing this nonlinear coupled system predicts that the physical and chemical processes connecting ions, vapors, and aerosols effectively constrain the particle population to a relatively narrow range of values. This self-limiting behavior may explain in part the apparent stability of the marine sulfate aerosol, with mean concentrations of the order of several hundred per cubic centimeter.

Aerosols↗
PubMed2000

[Transmission and genetic effect of ting chromosome in cross progenies from octoploid Tritileymus with 4D nullisomic].

A pair of ting chromosomes (ti) added to 72180 4D nullisomic was subcentral centromere chromosome and was about 1/3-1/4 the size of a chromosome on the average length. It's chromosome configuration was 19.59" (18-20) + 0.46' (0-4) + 0.99" (0-1) + 0.96ti" (0-1) + 0.08ti' (0-2) at PMC MI. The cells with ring ti" account for 96.19%, of which 82.38% were free on each side of the equatorial plane. ti chromosome paired in advance, defered segregation and had no synapsis with a chromosome. When the cross progenies from 72180 4D nullisomic with octoploid Trilileymus were backcrossed to the 4D nullisomic used as the male, the transmitting rate of 2ti chromosome was six times higher than that where the nullisomic was used as the female. The transmitting and loss rates of ti chromosome were 50.38% and 18.34% respectively, and averagely each plant has 0.72 ti chromosome in the cross generations. The appearing rate of ti chromosome was 43.18% in root tip cell and 8.16% in PMC MI of the plants without ti chromosome. When the number of a chromosome was less than 42, the genetic effect of ti chromosome on the quantitative character was significant, while the number of a chromosome was 42, the genetic effect was not apparent.

Chromosomes↗
PubMed1998

Val 70, Phe 72 and the last seven amino acid residues of C-terminal are essential to the function of norepinephrine transporter.

The norepinephrine transporter(NET) is a member of the Na+/Cl- dependent neurotransmitter transporter family and constitutes the target of several clinically important antidepressants. To delineate the critical amino acid residues and the function of C-terminal in regulating transport activity of NET, here we constructed two site mutants (V70F, F72V; V70I, F72V) and one C-terminal truncated mutant (delta 611-617). The wild type and mutants of NET were expressed in Xenopus oocytes by injection of their cRNA. We found that all of these mutants lost their transport activity. These results indicate that the amino acid residues of V70 and F72, and the last seven amino acids of C-terminal are essential to the transport activity of NET.

Amino Acid Sequence↗
PubMed1996

Regeneration of myelinated fiber after crush injury is retarded in sciatic nerves of mutant Japanese quails deficient in neurofilaments.

Regeneration of myelinated fibers in the sciatic nerve 2 weeks after crush injury was studied morphometrically in mutant Japanese quails deficient in neurofilaments and in normal quails (controls). There were fewer regenerated myelinated fibers per nerve at 10 mm (R1) and 20 mm (R2) distal to the crush site in mutants than in controls (P < 0.05). Both median and maximum diameters were smaller (P < 0.01) in mutants than in controls. On electron microscopy, transverse axonal area and axonal circumference were smaller (P < 0.001) at both R1 and R2 in mutants than in controls. The number of myelin lamellae was less (P < 0.01) in mutants than in controls at R1, but was similar at R2. There were fewer myelin lamellae in relation to axonal area in mutants than in controls at R1 (P < 0.0001) and R2 (P = 0.0032). The results indicate a retardation of both radial growth of axons and myelination around axons of the same size in mutants compared with controls. Such retardation may be explained by the deficiency of neurofilaments and the altered relationship between Schwann cell and axon in the mutant.

Animals↗
PubMed1995

Smaller axon and unaltered numbers of microtubules per axon in relation to number of myelin lamellae of myelinated fibers in the mutant quail deficient in neurofilaments.

To characterize the morphological features of the myelinated fibers in the mutant quails deficient in neurofilaments (NF), caused by a nonsense mutation in the NF-L gene, the morphological parameters of the axon and myelin sheath, and their relationships in the peroneal nerve were evaluated. In the mutant, the axonal area was smaller than in the control (P > 0.01), reflecting the lack of large diameter axons. There was no significant difference in the mean number of myelin lamellae and of their spacings between controls and mutants. Therefore, it was decided to analyze the alteration of axonal parameters in relation to the number of myelin lamellae. In the regression analysis, the number of microtubules (MT) per square micrometer of the axonal area was greater in the mutant than in the control (P < 0.05); however, the number of MT per axon was similar in controls and mutants with the same given number of myelin lamellae. The number of MT+NF per axon was smaller in the mutant than in the control only for myelinated fibers with more than 25 myelin lamellae (P > 0.05). These findings indicate that there was a less significant effect of NF deficiency on the smaller than on the larger myelinated fibers. There was no compensatory increase in the numbers of MT per axon of the myelinated fibers in the mutant as found previously in the unmyelinated fibers of the mutant.

Animals↗
PubMed1994

Greater number of microtubules per axon of unmyelinated fibers of mutant quails deficient in neurofilaments: possible compensation for the absence of neurofilaments.

Morphometric evaluations were performed on the peroneal nerve from mutant quails deficient in neurofilaments (NF) to elucidate the effect of an absence of NF on unmyelinated axons. The diameter frequency distribution of unmyelinated axons was similar between controls and mutants. The mean transverse axonal area, axonal circumference and circularity index of the unmyelinated axons were also similar in controls and mutants. However, the number of microtubules (MT) per axon was greater (P < 0.01) in the mutants than in the controls. The regression analysis relating the number of MT per axon to the diameter of unmyelinated axons indicated a greater number of MT in the mutants than in the controls (P < 0.05-0.01). A significantly greater number of MT per axon in the mutants may suggest a compensatory increase of MT in the absence of NF. This may conserve the size and transverse circular profile of the unmyelinated axons which are probably maintained by both MT and NF in the controls. The number of MT may be increased at the expense of the soluble fraction of tubulin.

Animals↗
PubMed1993

Smaller number of large myelinated fibers and focal myelin thickening in mutant quails deficient in neurofilaments.

The peripheral nervous system of a mutant of a Japanese quail deficient in neurofilaments (mutant) and of a normal Japanese quail (control) was morphometrically evaluated to characterize the morphological findings, especially those of the myelinated fibers of the mutant. In the proximal peroneal nerves, the frequency of the teased myelinated fibers showing the focal myelin thickening was higher in mutant than in control (P < 0.001) without obvious ongoing axonal degeneration and segmental demyelination. The total numbers of the myelinated fibers in the proximal and distal peroneal nerve, and in the tibial nerve branch to gastrocnemius muscle (pars medialis) were similar between control and mutant, although the number of the large myelinated fibers was less (P < 0.01) and the number of the small myelinated fibers was greater (P < 0.01) in mutant compared with control. The median diameters of neuronal cell bodies of the sacral dorsal root ganglia were similar in control and mutant. The percentages of light, dark and unclassified cells evaluated based on the histologic cytoplasmic features were also similar in control and mutant. Therefore, morphometric alterations were more pronounced in the peripheral myelinated nerve fibers compared with those in the cell bodies of the spinal dorsal root ganglia. We concluded that a smaller number of large myelinated fibers with a greater number of small myelinated fibers and the presence of focal myelin thickening are the main morphologic findings in this mutant, probably due to the arrest of radial growth or maturation of the axons of the myelinated fibers in the absence of ongoing myelinated fiber degeneration.

Animals↗
PubMed1992

[Later onset metachromatic leukodystrophy diagnosed by nerve biopsy].

Three cases of later onset metachromatic leukodystrophy in one family were reported. The brother is 32 years old, younger sister is 35 years old and the elder sister is 39 years old, who were normal as child without any family history of neurological disease. The three cases began their illness at about the age of 30 years old with dysarthria, progressive dementia, motor disturbance and numbness in the extremities. CT scan showed low density in the white matter of frontal, parietal lobes and around the ventricle. The written reports of CT scan were lacunar infarction in brother, multiple lacunar infarction in younger sister and Binswanger's disease in elder sister. Nerve biopsy showed myelinated fibers were decreased in number. Metachromatical materials were seen in and around the Schwann cell cytoplasm. Metachromatical materials were lamillar inclusions in granular matrix by electromicroscopic examination. So nerve biopsy is easy, safe and effective method to diagnose the uncertain pathogenic leukoence-phalopathy.

Adult↗
PubMed1989

[Experimental analysis of membrane potential changes during maturation of Bufo bufo gargarizans oocytes].

The full-grown oocytes obtained from toad (bufo bufo gargarizans) submitted in hibernation state or reared at 25-30 degrees C for several months, named hibernation oocyte or high temperature oocyte, had a membrane potential of -41.51 +/- 0.77 mV and -43.83 +/- 1.39 mV in Ringer's solution respectively. The hibernation oocytes underwent GVBD (germinal vesicle breakdown) and membrane depolarization at 19 +/- 1 degree C after progesterone stimulation. The membrane potential was about -20 mV at the period of GVBD, and -10 mV or so at 20 hours after the hormone treatment. However, the high temperature oocytes did not undergo GVBD, their membrane potential decreased before the fourth hour after treatment with progesterone and then recovered. If the hibernation oocytes were preincubated at 37-38 degrees C for 13 hours prior to the culture in the medium containing progesterone (10(-6)M, 37-38 degrees C), no GVBD was observed and the membrane depolarized before the fourth hour after treatment with progesterone then recovered, but MPF was detectable in the cytoplasm (unpublished). Both GVBD and membrane depolarization appeared in the hibernation oocytes and high temperature oocytes after injection of MPF. The time required for the hibernation oocytes injected MPF to attain the membrane potential about -20 mV was 4 hours earlier than that of progesterone treatment. It was just the time required for the appearance of MPF in the cytoplasm of oocytes treated with the hormone. It was noticed in our precedent article that a factor which appeared in the cytoplasm of high temperature oocytes differed from MPF. The factor was called Hibernation Oocyte Mature Promoting Factor (HOMPF).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

[Immediate type anaphylaxis of streptomycin allergy elicited by streptomycin polymers].

It has been known that streptomycin (SM) can cause some immediate type anaphylaxis even anaphylactic shock in clinical therapy. The characteristic of the substance that elicits the allergic reaction has not been reported. Using gel filtration and high performance gel permeation chromatography (HPGPC), we have found that some impurities of high molecular weights (HMW) were formed by heating acidic SM solution. The HMW impurities had a colour reaction with citric acid-acetic anhydride reagent and elicited passive cutaneous anaphylaxis (PCA) on guinea pigs sensitized with rabbit anti-SM-BSA serum and general anaphylaxis in guinea pigs immunized by SM-BSA. It is suggested that the impurities, SM polymers (poly-SM) related to some reactions on amino groups of SM, are the allergens of SM allergy.

Animals↗
PubMed1987

Retrograde transport and differential accumulation of serum proteins in motor neurons: implications for motor neuron diseases.

We found immunocytochemical evidence of serum albumin and immunoglobulin G in motor neurons of rats under physiologic conditions, but not when axoplasmic flow was abolished. The amount of serum proteins was highest in somatic motor neurons of the spinal anterior horn, nucleus ambiguous, and trigeminal motor nucleus; less in hypoglossal and facial neurons; and sparse in preganglionic autonomic, oculomotor, and hypothalamic neurons. Toxic or trophic substances, bound to serum proteins, could also be incorporated into motor neurons. Quantitative differences in accumulation paralleled the selective vulnerability of somatic motor neurons in motor neuron diseases.

Animals↗
PubMed1986

Immunohistochemical demonstration of viral antigens in Japanese encephalitis.

Japanese encephalitis virus antigens were immunohistochemically demonstrated in formalin-fixed paraffin sections from an autopsied brain. Glial nodules were always associated with antigen-positive cell debris. Glia shrubs in the cerebellar cortex appeared to be formed along the apical dendrite of Purkinje cells. Most, but not all, of the neurons involved in neuronophagia were viral antigen positive. Antigenic masses were occasionally encountered in the center of so-called acellular plaques. Neurons with strong viral antigens were sporadically found in normal-appearing regions in the thalamus and cerebral cortex. Viral antigens were demonstrable only in neurons and not in glial or vascular endothelial cells.

Adult↗