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Biomedical subjects

B Shao

Publications and source records attributed to B Shao.

At least 19 recordsLinked to original sources
PubMed2006

Evaluation of the economic and environmental impact of converting cropland to forest: a case study in Dunhua county, China.

The Sloping Land Conversion Program (also known as "Grain for Green" or the Upland Conversion Program) for converting cropland to forest is one of China's most ambitious environmental initiatives, and is one of the world's largest land-conservation programs with a budget of RMB 337 billion (over US$ 40 billion). Although environmental impacts have played a vital role in the general reasoning and argumentation for forest plantations, environmental impact analyses have often received less attention than economic analyses in the planning of plantation forestry projects. The overall goal of this paper is to evaluate the program's environmental impact considering the farmer's interests and the potential social benefits due to carbon sequestration in different scenarios based on household and field survey data in Dunhua County. Our findings are that: (1) in many cases, the program did not give adequate consideration to land productivity and environmental heterogeneity when selecting plots; (2) more than half of the reforestation plots were on flat cropland (slopes of less than 5 degrees ); (3) in five of the eight townships, net incomes on reforested land were substantially above or below previous crop incomes, raising questions about the efficiency of the allocation of compensation to farmers participating in the program; (4) the potential carbon co-benefit increased the NPV of the program by 5954-7009 RMB/ha. In conclusion, we recommend that more attention should be paid to the quality of reforestation programs rather than just their scale and note that consideration of potential carbon sequestration co-benefits enhances the benefits of cropland conversion programs.

Carbon↗
PubMed2004

Differential effects of repeated restraint stress on pulsatile lutenizing hormone secretion in female Fischer, Lewis and Wistar rats.

Stress activates the hypothalamic-pituitary-adrenocortical (HPA) axis and can suppress pulsatile luteinizing hormone (LH) secretion, resulting in reproductive dysfunction. The histocompatible inbred Fischer and Lewis rat strains exhibit marked phenotypic differences in the activity of the HPA axis, the former being more reactive. Using Fischer, Lewis and Wistar rats, we assessed effects of repeated restraint stress on pulsatile LH secretion. Adult rats were ovariectomized and fitted with cardiac catheters. Blood samples were collected at 5-min intervals for 3-5 h for detection of LH. Less frequent samples were collected for corticosterone measurement. After 2 h, rats were restrained for 60 min. The same regimen was repeated four times at 6-day intervals. The mean peak corticosterone levels achieved during the first restraint in Fischer rats were significantly higher than those in Lewis and Wistar rats. By the time of the fourth episode of restraint, there had been some adaptation of the corticosterone response in the Fischer, but not in the Lewis or Wistar rats. LH pulses were interrupted during the 1st restraint in all experimental groups, although only Fischer rats showed suppression of LH pulses during the subsequent 2-h postrestraint period. During the fourth restraint, LH pulse frequency was still reduced in Wistar, but not in Fischer and Lewis rats, both of which showed a complete habituation. These results suggest that differential control mechanisms underlie the response of the HPA and HPG axes to repeated restraint stress.

Adaptation, Physiological↗
PubMed2001

Sex-related differences in nortriptyline-induced side-effects among depressed patients.

1. Men and women may differ in their pharmacokinetic responses to tricyclic antidepressants (TCAs), in a number of autonomic indices, and in various adrenergic receptor mediated responses. Emerging evidence also suggests that women may have a lower rate of serotonin synthesis in brain and a greater sensitivity to the depressant effects of tryptophan depletion, relative to men. However, sex-related differences in TCA-induced side-effects, including increases in heart rate (HR), dry mouth, constipation, and difficulty urinating, has not been systematically investigated. 2. The authors examined potential sex-related differences in the pattern of side-effects during treatment with nortriptyline (NT), a TCA that is still widely used. Seventy-eight healthy outpatients who met Research Diagnostic Criteria and DSM-III-R criteria for major depression participated in a double-blind, randomized parallel trial of NT versus placebo. 3. Each subject was acutely challenged with either placebo or 50 mg NT prior to and after a 6-week treatment with NT. NT doses were adjusted weekly to maintain therapeutic plasma levels. Patients were assessed at multiple time points to detect the presence of NT-induced side-effects. 4. The initial, single (50 mg) dose of NT significantly increased supine HR. Six-week treatment with NT was found to significantly increase supine and sitting HRs, irrespective of sex. In rechallenge with the single NT dose, there were no significant effects on HR. 5. When sex-related differences were examined, HR increases were greater in men than women during weeks 4 through 6 of the NT treatment, although no sex-related differences were present in plasma NT levels or metabolites. In addition, there was a significant NT to placebo difference in self-rated dry mouth for women during all 6-weeks of treatment, whereas men showed a significant NT-placebo difference during weeks 3 and 5. 6. The results suggest the presence of sex-related differences in elevated supine HR response during the course of 6-week NT treatment. Depressed men may be more susceptible to NT-induced increases in supine HR than women.

Adult↗
PubMed1998

Decreases in plasma A beta 1-40 levels with aging in non-demented elderly with ApoE-epsilon 4 allele.

This report examines plasma amyloid beta proteins A beta 40 and A beta 42 and apolipoprotein E (apoE) levels and their relationships with age in non-demented older adults with (N = 32) or without the apoE-epsilon 4 allele (N = 94). A beta levels did not differ between the groups whereas the epsilon 4 allele was associated with a significant reduction in plasma apoE. In subjects with the epsilon 4 allele, increasing age was associated with significant reduction in plasma A beta 40. Subjects without the epsilon 4 allele showed a significant positive correlation between A beta 40 and A beta 42 levels. There was also a significant correlation between plasma A beta 40 and apoE levels in all subjects.

Aging↗
PubMed1998

[Intensity of electromagnetic field and electric current on human bodies induced by electric blanket].

OBJECTIVE: To study the effects of various factors, such as different carriers, with or without ground connection to a blanket and status of its switch, on electromagnetic field induced. METHODS: To determine electric field, magnetic field and electric current on human bodies induced by electric blanket with a temperature--adjustable semiwave rectifier diode, which was domestically popular. RESULTS: Temperature was adjusted and controlled by a diode serially connected to its switch is put on and the blanket, with or without short circuit. When the switch is put on and the blanket is running in low temperature, if the diode is serially connected to the ground end of the power source, the intensities of electromagnetic field and current on the human bodies induced by the blanket was higher than those running in high temperature. CONCLUSION: The most important factor influencing field intensities of the electric blanket is in its switch.

Bedding and Linens↗
PubMed1998

[Radical neck dissection in treating cervical lymph node tuberculosis].

OBJECTIVE: To evaluate the significance of radical neck dissection in treatment of mixed-type cervical lymph node tuberculosis. METHOD: One hundred twenty-two cases with mixed-type cervical lymph node tuberculosis were treated with radical neck dissection and the results of the treatment were reported. The size, number, location and pathologic types of abscess, fistula and lymph node were also analyzed. RESULT: All the patients were cured without relapse during 1-7 year follow-up. Spreading antegrade infection and chronic recurrence were found to be the characteristics of mixed-type cervical lymph node tuberculosis. CONCLUSION: Radical neck dissection is an effective and safe approach for treating the disease.

Adolescent↗
PubMed1996

Studies on bioactive saponins from Chinese medicinal plants.

In our recent studies on bioactive saponins, two Chinese medicinal plants: Mussaenda pubescens Ait.f (Rubiaceae) and Clematis chinensis Osbeck (Ranunculaceae), were investigated. Of the two medicinal plants, M. pubescens is a Chinese folk medicine which has been used as a diuretic, antiphlogistic, diaphoretic and antipyretic agent, and has also been used to detoxify mushroom poisons and to terminate early pregnancy. Clematis chinensis is a Chinese traditional medicine which has been used as an analgesic, diuretic, antitumor, antiinflammatory and insecticidal agent for ages. As a result of our studies, eighteen saponins were identified from M. pubescens, among which seventeen were new compounds, while eleven saponins were isolated from C. chinensis, three of which were new compounds. In the course of our structural studies, mass fragment analysis in FAB-mass spectra and 1H- and 13C-NMR spectra were used to determine the structures of the sapogenin and oligosaccharide moieties. In those more complicated and minor saponins, various 2D-NMR experiments were carried out on 400-, 500- or 600-MHz NMR instruments, which permitted the identification of new sapogenins in glycoside form. In addition, it was also possible to assign all the proton and carbon signals of the sugar units on the basis of 1H-1H DQF COSY, TOCSY and HMQC spectra, which further permitted the establishment of linkage sites and sequences among the sugar units and aglycones by means of NOESY, ROESY and HMBC spectra. When the proton signals of sugar units are overlapped seriously in 1H-NMR spectra, peracetylation is a very helpful technique which can spread proton signals in wider range, thus simplifying their assignment by means of 2D-NMR spectra. When some of the sugar proton signals of a peracetylate are also overlapped coincidentally, alternation of deuterated solvents for measuring NMR spectra can circumvent the difficulties. Pharmacological tests indicated that mussaendoside O, the most abundant saponin from M. pubescens, can inhibit significantly the secretions of the lachrymal and salivary glands induced by galanthamine, and can also inhibit the contraction of the isolated longitudinal muscle strip from guinea pig ileum evoked by an M-Ach receptor agonist (carbachol, 10(-6) M) at concentrations of 10(-4) and 10(-5) M. From these results, the saponin should be an antagonist of the M-Ach receptor, and was presumed to be responsible for its antitoxicity activity toward some mushroom poisons of medicinal plant origin. In addition, mussaendoside O also showed immunopromotive and hemolytic activities.

Animals↗
PubMed1996

[Changes in sexual hormones and bone metabolism disorder in postmenopausal NIDDM patients].

In the present study the bone mineral content (BMC) was measured with a single photoabsorptionmeter in 31 diabetic menopausal females and 45 normal menopausal females, simultaneously the serum level of estradiol (E2), testosterone (T), parathyroid hormon (PTH) and calcitonin (CT) were measured with radioimmunoassay. The results showed, BMC, E2 and CT in diabetic group were significantly lower than in the control group. The serum level of PTH in diabetic group was significantly higher than in the control group. The multiple regression-analysis showed that chiefly the level of E2 in the diabetic group was closely related with BMC. Serum E2 stimulate directly the osteoblasts for the bone reconstruction and increased the bone tissue sensibility to PTH. CT is the antagonistic hormone of PTH and protects the bone mineralization. Hyperglycemia may cause the damage of ovarium and decreased E2-secretion. The lowered E2 level results in combination with elevated PTH and lowered CT level in serum obviously, in loss of a large amount of bone mineral content and in developing the diabetic osteoporosis.

Aged↗
PubMed1996

Saponins from Clematis chinensis.

From ethanol extracts of the roots of Clematis chinensis, a new saponin, named clematichinenoside C, was isolated and its structure was established as 3-O-beta-D-glucopyranosyl-(1-4)-beta-D-ribopyranosyl-(1-3)-alpha-L - rhamnopyranosyl-(1-2)-alpha-L-arabinopyranosyl oleanolic acid 28-O-alpha-L-rhamnopyranosyl-(1-4)-beta-D-glucopyranosyl- (1-6)-beta-D-glucopyranosyl ester by spectroscopic and chemical means. In addition, one known saponin, huzhongoside B, was identified in the plant.

Carbohydrate Sequence↗
PubMed1996

[Changes of plasma levels of monoamines in normal pregnancy and pregnancy-induced hypertension women and their significance].

OBJECTIVE: To study the changes of plasma levels of monoamines in pregnant women and investigate the relationship between the monoamines and pregnancy induced hypertension (PIH). METHODS: Using fluorescence spectrophotometry, we determined the contents of plasma monoamines in 130 normal pregnant (NP), 32 normal non-pregnant (NNP), and 58 PIH women. RESULTS: The levels of norepinephrine (NE) in NP from the 2nd trimester to parturiency were more markedly increased than those of the 1st trimester and of NNP (P < 0.05). The levels of dopamine (DA) and 5-hydroxytryptamine (5-HT) were also obviously increased at the 2nd and 3rd trimester respectively (P < 0.05). Compared with NP, the contents of DA in moderate and severe PIH were markedly and very markedly decreased respectively (P < 0.05 and P < 0.01), while the levels of 5-HT in PIH increased significantly (P < 0.05). NE in PIH was also tending to increase. CONCLUSION: The changes of monoamines may be one of the causes of small artery spasm in PIH.

Adult↗
PubMed1995

Triterpenoid saponins from Clematis chinensis.

From the roots of Clematis chinensis, two new triterpenoid saponins, named clematichinenoside A and B, were isolated and their structures were elucidated as 3-O-beta-D-ribopyranosyl-(1-3)-alpha-L-rhamnopyranosyl-(1-2)-alpha -L- arabinopyranosyl oleanolic acid 28-O-beta-D-glucopyranosyl ester and 3-O-beta-D-glucopyranosyl-(1-4)-beta-D-ribopyranosyl-(1-3)-alpha-L - rhamnopyranosyl-(1-2)-alpha-L-arabinopyranosyl hederagenin 28-O-alpha-L-rhamnopyranosyl-(1-4)-beta-D-glucopyranosyl-(1-6)- beta-D-glucopyranosyl ester, respectively. In addition oleanolic acid, hederagenin and seven known saponins were obtained.

Carbohydrate Conformation↗
PubMed1994

[Effect of trifluoroacetoprimaquine on erythrocytic schizonts of rodent malaria].

Effect of trifluoroacetoprimaquine oxalate (M8506) and primaquine (PQ) on blood schizonts of Plasmodium berghei were determined using the method of 4-day suppressive test within extended observation period of 60 d. When mice infected with Plasmodium berghei ANKA strain were treated ig with M8506 or PQ at a same daily dose of 20 mg/kg for 4 d, the cure rates were 100% and 90%, respectively. The two drugs also showed prominent suppressive effects on chloroquine-resistant P. berghei NS line and pyronarine-resistant P. berghei RP line, but the parasitemia still remained positive or all of the mice treated recrudesced, indicating the existence of cross resistance between trifluoroacetoprimaquine and other erythrocytic schizonticides, including chloroquine and pyronaridine.

Animals↗