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Biomedical subjects

Z Mo

Publications and source records attributed to Z Mo.

At least 19 recordsLinked to original sources
PubMed2005

Effect of Brn-3a deficiency on primary nociceptors in the trigeminal ganglion.

Immunohistochemistry for substance P, somatostatin and vanilloid receptor subtype 1 as well as receptors for somatostatin and opioids was performed on the trigeminal ganglion in wild-type and Brn-3a knockout mice at postnatal day 0. In wild-type mice, the trigeminal ganglion contained abundant substance P-, vanilloid receptor subtype 1-, sst2A receptor- and delta-opioid receptor-immunoreactive neurons, while the ganglion had only a few mu-opioid receptor-immunoreactive neurons. The Brn-3a deficiency had an effect on the cell size but not the number of substance P-immunoreactive neurons. In knockout mice, the proportion of small immunoreactive neurons markedly increased and that of medium- to large-sized immunoreactive ones correspondingly decreased (mean +/- S.D. = 54.7 +/- 29.1 microm2, range = 10.9-220.8 microm2) compared to wild-type mice (mean +/- S.D. = 116.6 +/- 58.6 microm2, range = 27.3-400.7 microm2). As for vanilloid receptor subtype 1-immunoreactive neurons, the number and cell size was barely affected by the deficiency. On the other hand, the loss of Brn-3a caused a decrease in the number of sst2A receptor- or delta-opioid receptor-immunoreactive neurons (more than 95% reduction) and an increase in the number of mu-opioid receptor-immunoreactive neurons (9.3-fold increase). Somatostatin-immunoreactive neurons were not detected in the trigeminal ganglion of wild-type or mutant mice at postnatal day 0. The present study suggests that Brn-3a deficiency may have effects on the survival of trigeminal nociceptors and their expression of some neurochemical substances.

Animals↗
PubMed2004

Effect of Brn-3a deficiency on parvalbumin-immunoreactive primary sensory neurons in the dorsal root ganglion.

Immunohistochemistry for parvalbumin, a marker for primary proprioceptors, was performed on the dorsal root ganglion (DRG) of wildtype and knockout mice for Brn-3a at postnatal day 0 and embryonic day 18.5. The DRG contained many parvalbumin-immunoreactive (ir) neurons in wildtype (5.4%) and knockout mice (5.6%). Cell size analysis demonstrated that such neurons were mostly medium-sized to large in these mice. Therefore, it is unlikely that the survival of proprioceptors is dependent upon Brn-3a in the DRG. In the dorsal column and gray matter of the spinal cord of knockout mice, however, parvalbumin-ir nerve fibers were sparse compared to wildtype mice. The number of parvalbumin-ir varicosities around motoneurons decreased in the mutant. Thus, our data suggest that Brn-3a may play an important role in the central projection and terminal formation of DRG proprioceptors in the spinal cord.

Afferent Pathways↗
PubMed2003

The transportation, time-dependent distribution of heavy metals in paddy crops.

Sixteen experimenmtal plots (5 m x 6 m = 30 m2) were designed with four different levels of heavy metals (HMs) concentration in soil. The concentrations of heavy metals in soils, and paddy plant during the different periods of growth were investigated. A relationship between the total HM content in plants and the HM level in soil was found for a wide range of concentrations. The exchangeable fraction of HMs extracted with 1 M MgCl2 solution according to Tessier's method increased correlation with the dosage of supplemented HMs, then decreased as time went on. The time-related variation of exchangeable HMs in soil demonstrated that the amount of effective HMs taken up by paddy differed at various growth phases. The amount of HMs accumulated in different parts of paddy followed the order of root > stem > grain, leaf. The transportation potential of the HMs in paddy in present study followed the order of Zn, Cr > Cd, Cu > Pb. The HM content in root, stem and leaf of paddy plant (dry weight) was low at time of seedling. The concentration in the root increased sharply at time of tillering, decreased thereafter. The concentrations in stem and leaf reached the highest at time of tillering, then decreased, while rose slightly at following time.

Biological Transport↗
PubMed2002

Effect of Brn-3a deficiency on nociceptors and low-threshold mechanoreceptors in the trigeminal ganglion.

Immunohistochemistry for protein gene product 9.5 (PGP 9.5, a neuron specific protein) and vanilloid receptor 1-like receptor (VRL-1, a marker for medium-sized to large primary nociceptors) were used to assess the effects of Brn-3a deficiency on neuronal innervation of oral tissues and neurons of the trigeminal ganglion (TG). In the knockout mouse, the number of PGP 9.5-immunoreactive (-ir) nerve fibers decreased in the facial cutaneous and oral mucous epithelia, as well as the incisor and molar tooth germs. The reduction of PGP 9.5-ir Merkel endings was also observed in some vibrissae. No obvious change was detected in other tissues. Cell size analysis demonstrated that the proportion of small neurons markedly increased while that of medium-sized and large neurons significantly decreased in the TG of the mutant. Moreover, Brn-3a deficiency caused the disappearance of TG neurons which were immunoreactive for VRL-1. Together, our data suggest that nociceptors and low-threshold mechanoreceptors with medium-sized to large cell bodies may be sensitive to the loss of Brn-3a.

Afferent Pathways↗
PubMed2002

Short-term responses of Oryzias latipes (Pisces: Adrianichthyidae) and Macrobrachium nipponense (Crustacea: Palaemonidae) to municipal and pharmaceutical waste water in Beijing, China: survival, behaviour, biochemical biomarkers.

Whole effluent toxicity was assessed for the fish Oryzias latipes and the prawn Macrobrachium nipponense for 18 h in a dilution series (0-66%) of the inflow and effluent of a municipal waste water treatment plant as well as waste water from a teramycin producing pharmaceutical industry, before, during and after a pilot laboratory purification process. The waste waters caused acute toxicity as measured by inhibition of light emission in the luminiscent bacterium Vibrio qingaiensis sp. nov. (Q67). EROD and aryl hydrocarbon hydroxylase activity in in vitro carp liver-cells showed a dose-dependent toxic response to the municipal waste water. Behavioural responses and time-to-death of fish and prawn, recorded online with the "Multispecies Freshwater Biomonitor" proved to be concentration- and time-dependent sensitive toxicity indicators in both types of waste water. Behaviour changed stepwise from normal activity to (increased or decreased) activity to more time spent on ventilation and finally to increased morbidity at higher concentration and time of exposure. The municipal waste water treatment plant managed to reduce toxicity to bacteria (Q67), prawn and fish. The pharmaceutical waste water treatment process still has to be improved, in order to reduce toxicity for fish and prawn.

Animals↗
PubMed2002

Effect of Brn-3a deficiency on parvalbumin-, calbindin D-28k-, calretinin- and calcitonin gene-related peptide-immunoreactive primary sensory neurons in the trigeminal ganglion.

Immunohistochemistry for parvalbumin, calbindin D-28k, calretinin and calcitonin gene-related peptide (CGRP) was performed on the trigeminal ganglion and oro-facial tissues in Brn-3a wildtype and knockout mice at embryonic day 18.5 and postnatal day 0. In wildtype mice, the trigeminal ganglion contained abundant parvalbumin-, calbindin D-28k- and CGRP-immunoreactive neurons while the ganglion was almost devoid of calretinin-immunoreactive neurons. In Brn-3a knockout mice, a 63% decrease of parvalbumin-immunoreactive neurons was detected. In contrast, the absence of Brn-3a dramatically increased the number of calbindin D-28k-immunoreactive (3.5-fold increase) and calretinin-immunoreactive neurons (91-fold increase). The number of CGRP-immunoreactive neurons, however, was not altered by the Brn-3a deficiency. Cell size analysis indicated that loss of Brn-3a increased the proportions of small (<100 microm (2)) parvalbumin-, calbindin D-28k- and CGRP-immunoreactive neurons while it decreased those of large (>200 microm(2)) immunoreactive cells. Calretinin-immunoreactive neurons were either small or medium (100-200 microm (2)) in mutant mice. The oro-facial tissues contained parvalbumin-, calbindin D-28k- and CGRP-immunoreactive fibers, but not calretinin-immunoreactive ones in wildtype mice. In Brn-3a knockout mice, the number of parvalbumin-immunoreactive fibers markedly decreased in the infraorbital nerve and parvalbumin-immunoreactive endings disappeared in the vibrissa. In contrast, the number of calbindin D-28k-immunoreactive fibers increased significantly in the infraorbital and mental nerves. In addition, calbindin D-28k-immunoreactive endings appeared in the vibrissa. As well, some fibers showed calretinin-immunoreactivity in the infraorbital nerve of the mutant. However, no obvious change of CGRP-immunoreactive fibers was observed in the oro-facial region of knockout mice. Taken together, our data suggest that Brn-3a deficiency has effects on the expression of neurochemical substances in the trigeminal ganglion.

Animals↗
PubMed2001

The Ath5 proneural genes function upstream of Brn3 POU domain transcription factor genes to promote retinal ganglion cell development.

During retinogenesis, the Xenopus basic helix-loop-helix transcription factor Xath5 has been shown to promote a ganglion cell fate. In the developing mouse and chicken retinas, gene targeting and overexpression studies have demonstrated critical roles for the Brn3 POU domain transcription factor genes in the promotion of ganglion cell differentiation. However, the genetic relationship between Ath5 and Brn3 genes is unknown. To understand the genetic regulatory network(s) that controls retinal ganglion cell development, we analyzed the relationship between Ath5 and Brn3 genes by using a gain-of-function approach in the chicken embryo. We found that during retinogenesis, the chicken Ath5 gene (Cath5) is expressed in retinal progenitors and in differentiating ganglion cells but is absent in terminally differentiated ganglion cells. Forced expression of both Cath5 and the mouse Ath5 gene (Math5) in retinal progenitors activates the expression of cBrn3c following central-to-peripheral and temporal-to-nasal gradients. As a result, similar to the Xath5 protein, both Cath5 and Math5 proteins have the ability to promote the development of ganglion cells. Moreover, we found that forced expression of all three Brn3 genes also can stimulate the expression of cBrn3c. We further found that Ath5 and Brn3 proteins are capable of transactivating a Brn3b promoter. Thus, these data suggest that the expression of cBrn3c in the chicken and Brn3b in the mouse is initially activated by Ath5 factors in newly generated ganglion cells and later maintained by a feedback loop of Brn3 factors in the differentiated ganglion cells.

Animals↗
PubMed2001

Monitoring priority pollutants in a sewage treatment process by dichloromethane extraction and triolein-semipermeable membrane device (SPMD).

Semipermeable membrane devices containing a neutral lipid triolein (triolein-SPMD) and conventional dichloromethane extraction were used to monitor the presence and concentrations of priority organic pollutants in a sewage treatment process in Beijing, China. Both samples gave similar information on the presence of target PCB congeners, PAHs, Organochlorine pesticides and substituted benzenes in sewage at all sites. After 20 days' sampling, the concentrations of contaminants in triolein of SPMD were much higher than those in dichloromethane extracts, which resulted in easier analysis, improved the detection limits, and increased the accuracy. Previous field mean sampling rates for SPMD were used to estimate concentrations of PCB congeners in sewage, which compared to their determined concentrations by dichloromethane extraction. The consistency and superiority of SPMD technology were proved for the detection of priority organic contaminants from sewage. Lower removal rates for PCB congeners and PAHs coincided with the persistence of them in environment. More attention should be paid to urban sewage treatment process adopting activated-sludge method, where priority organic pollutants might not be removed, even present higher concentrations after treatment.

Environmental Monitoring↗
PubMed2001

[Regulation on the immunological effect of mogrosides in mice].

OBJECTIVE: To investigate the cellular immunological effect of mogrosides in mice. METHODS: Mogrosides was administered to normal or CTX-induced immunosuppressive mice, and their macrophage function and T lymphocyte proliferation were detected. RESULTS: Mogrosides could promote phagocytosis and T lymphocyte proliferation significantly in the CTX-induced immunosuppressive mice, but not in the normal mice. CONCLUSION: The results suggested that mogrosides had certain up-regulation on cellular immunity in the CTX-induced immunosuppressive mice.

Animals↗
PubMed2000

Mechanism of antihypertensive effect of dietary potassium in experimental volume expanded hypertension in rats.

Dietary potassium supplementation lowers blood pressure (BP) and attenuates complications in hypertensive subjects, particularly those with the low renin volume expanded (LRVE) variety. We and others have shown that the plasma level of a digitalis like substance (DLS) is elevated in this type of hypertension. We therefore, examined the effect of increases in dietary potassium on the plasma level of endogenous DLS, myocardial and renal Na+, K+-ATPase (NKA) activities, BP, and renal excretory function in reduced renal mass (RRM)-salt hypertension in the rat, a classical model of LRVE hypertension. 70% RRM rats were divided in 4 groups, namely those consuming: 1) a sodium free and normal potassium (1.3% as KCl) diet (RRM-0 Na), 2) a normal sodium and normal potassium diet (RRM-NaK), 3) a normal sodium and high potassium (2 X normal) diet (RRM-Na2K), and 4) a normal sodium and 4 times normal potassium diet (RRM-Na4K). At the end of 4 weeks of dietary treatment, direct BP was recorded, plasma level of DLS determined by bioassay and with a radioimmunoassay for digoxin (DIF) and myocardial and renal NKA activities were measured. As expected, compared to RRM-0Na rats, RRM-NaK rats developed hypertension. BP increased significantly less in RRM-Na2K, whereas BP did not increase in RRM-Na4K rats. Hypertension in RRM-NaK rats was associated with an increase in plasma DLS and DIF and decrease in renal and myocardial NKA activities. DLS was increased (DIF was not changed) and myocardial NKA also decreased in rats consuming double potassium. However, quadrupling potassium in the diet (RRM-Na4K) normalized DLS and DIF and increased myocardial and renal NKA activities, compared to RRM-0Na rats. Also compared to RRM-0Na, water consumption, urinary volume excretion, sodium, and potassium increased in the other 3 groups, more so in RRM-Na4K rats. These data show that quadrupling the potassium in the diet prevents the BP increase in RRM rats and this is associated with diuresis/natriuresis and normalization of DLS, perhaps because the diuresis/natriuresis normalizes blood volume.

Animals↗
PubMed2000

Reduction of obesity, as induced by leptin, reverses endothelial dysfunction in obese (Lep(ob)) mice.

Obesity is a major health care problem and is associated with significant cardiovascular morbidity. Leptin, a neuroendocrine hormone released by adipose tissue, is important in modulating obesity by signaling satiety and increasing metabolism. Moreover, leptin receptors are expressed on vascular endothelial cells (ECs) and mediate angiogenesis. We hypothesized that leptin may also play an important role in vasoregulation. We investigated vasoregulatory mechanisms in the leptin-deficient obese (ob/ob) mouse model and determined the influence of leptin replacement on endothelial-dependent vasorelaxant responses. The direct effect of leptin on EC nitric oxide (NO) production was also tested by using 4, 5-diaminofluorescein-2 diacetate staining and measurement of nitrate and nitrite concentrations. Vasoconstrictor responses to phenylephrine, norepinephrine, and U-46619 were markedly enhanced in aortic rings from ob/ob mice and were modulated by NO synthase inhibition. Vasorelaxant responses to ACh were markedly attenuated in mesenteric microvessels from ob/ob mice. Leptin replacement resulted in significant weight loss and reversal of the impaired endothelial-dependent vasorelaxant responses observed in ob/ob mice. Preincubation of ECs with leptin enhanced the release of NO production. Thus leptin-deficient ob/ob mice demonstrate marked abnormalities in vasoregulation, including impaired endothelial-dependent vasodilation, which is reversed by leptin replacement. These findings may be partially explained by the direct effect of leptin on endothelial NO production. These vascular abnormalities are similar to those observed in obese, diabetic, leptin-resistant humans. The ob/ob mouse may, therefore, be an excellent new model for the study of the cardiovascular effects of obesity.

Animals↗
PubMed2000

[The relationship of brainstem auditory evoked potential to cerebral blood flow volume in with vertebrobasilar transient ischemic vertigo].

This study was aimed at the relationship of brain-stem auditory evoked potential(BAEP) with cerebral blood flow(CBF) volume and vascular pathological changes in patients with vertebro-basilar transient ischemic vertigo (VBTIV). 65 patients were examined by magnetic resonance angiography(MRA), transcranial Dopplar(TCD) and BAEP; 26 controls were examined by MRA and TCD. In the patient group, MRA showed that vascular pathological changes were obvious in 50 patients, and obscure or absent in 15 patients. The CBF volume [112.3-278.9 ml/min (2s)] of control group was higher than that (48.0-262.0 ml/min) of the patients group (t = 2.43, P < 0.01) in which 15 patients had low CBF volume and 50 patients had normal CBF volume. The BAEP of 47(72.3%) patients was abnormal. Out of 15 patients with low CBF volume, 14(93.3%) had abnormal BAEP, but out of 50 patients with normal CBF volume, only 33(66%) patients had abnormal BAED (chi 2 = 4.34, P < 0.05). In the 50 patients with obscure obvious vascular pathological changes, 40(80%) patients had abnormal BAEP, but in the 15 patients with obscure or without the changes, only 7(43.3%) patients had abnormal BAEP (chi 2 = 4.86, P < 0.05). These results suggested that there might be a close relationship of BAEP with CBF volume and vascular pathological changes.

Adult↗
PubMed1999

[Changes in calcium and magnesium levels of lymphocytes in patients with diabetes and hypertension].

To investigate the cellular basis linking non-insulin-dependent diabetes mellitus(NIDDM) and hypertension, we used the atomic absorption spectrometry to detect Ca2+ and Mg2+ levels of serum and lymphocytes in patients with the above diseases. The results were that serum Ca2+ and Mg2+ levels had no change, but lymphocyte Ca2+ level increased obviously and lymphocyte Mg2+ level decreased obviously in both diseases, compared with normal controls. There were no difference between hypertension and NIDDM with and without hypertension. Ca2+ and Mg2+ levels of lymphocytes in patients with hypertension correlated with the systolic pressure respectively(Ca2+, r = 0.4633, P < 0.05; Mg2+, r = -0.4412, P < 0.05), but their levels in patients with NIDDM were not correlated with the fasting blood glucose. The results suggest that there is an abnormal Ca2+ and Mg2+ metabolism in lymphocytes in patients with hypertension and NIDDM.

Adult↗
PubMed1998

[Experimental study on hypoglycemic effect of YTY granules].

OBJECT: To perform experimental pharmacodynamic evaluation of a new TCM antidiabetic drug Yitangyin (YTY). METHODS: Experimkental streptozotocin induced rat diabetes models were subjected YTY treatment and the hypoglycemic effect was evaluated. The proved TCM Yusanxiao (YSX) was used as contrast. RESULTS: The low, middle and high dose YTY groups exhibited significant hypoglycemic effects on the model rats. The efficiency was comparable with YSX. CONCLUSION: The TCM YTY granule is an effective hypoglycmeic agent.

Animals↗
PubMed1998

[Comparison of pharmacological effects between cultispecies Sichuan Fritillary bulb (F. wabueasis, F. mellea) and wild Sichuan Fritillary bulb (F. unibracteata)].

The ethanol extracts from the cultured Sichuan Fritillary bulb have been proved similar to those from the wild one in treating coughing in mice, expectoration in rats, asthma in guinea pigs, bronchodilation of isolated lungs in mice, and cyclic nucleotide(cAMP, cGMP) in the plasma and lungs of mice. The acute toxicity of the cultured and wild species is also similar to each other. However, in terms of asthma relieving and cAMP level increment in the lungs, the cultured species F. wabueasis is significantly superior to the wild species of Fritillary bulb.

Animals↗
PubMed1998

[The estrogenic activities of 2-[3-estrone-N-ethyl-piperazine-methyl]tetracycline(XW630)--a new compound with anti-osteoporosis activity].

2-[3-Estrone-N-ethyl-piperazine-methyl] tetracycline (XW630) showing anti-osteoporosis activity is a new compound with piperazine-tetracycline in the steroid structure of estrone. The affinity of XW630 with uterine estrogen receptor and its estrogenic activity were studied in this paper. The relative affinities of estrone, estradiol and XW630 with estrogen receptor (ER) of the uterine myoma tissues were found to be 0.325, 1.000 and 0.011, respectively, by the competitive assay. The estrogenic activity index of estrone, estradiol and XW630 were shown to be 9.70, 10.30 and 6.90, respectively, by the uterine weight assay using immature mice. These indexes indicate that: the estrogenic activity of XW630 is about 1/1960 that of estrone and 1/7742 that of estradiol. The vaginal smear assay of oophorectomized mice also showed that the estrogenic activity of XW630 is less than that of estrone and estradiol.

Animals↗
PubMed1997

Determination of lignocaine hydrochloride by ion-pairing flow injection with piezoelectric detection.

A rapid and simple method for the determination of lignocaine hydrochloride by ion-pairing flow injection analysis was developed. It is based on the formation of an ion pair between lignocaine hydrochloride and sodium dodecyl phenylsulfonate and piezoelectric detection. The calibration curve was linear between 0.01 and 2.00 mg ml-1, with a detection limit of 8 micrograms ml-1, an RSD of 0.29% (10 replicates) and a sampling frequency of 120 h-1. The proposed method was satisfactorily applied to the determination of lignocaine hydrochloride in pharmaceutical preparations.

Flow Injection Analysis↗