Cigarette use in adolescents: the Cardiovascular Health in Children and Youth Study

Tobacco is the leading cause of preventable death in the United States, and its use is increasing in adolescents. To determine the interventions needed to prevent the initiation of smoking, it is important to know the factors related to tobacco use by adolescents. In this study the following factors related to cigarette use were examined: age, gender, ethnicity, self-esteem, physical activity, parental smoking, and socioeconomic status. Participants were 1,207 youth completing a written survey for the Cardiovascular Health in Children and Youth Study (CHIC II). Participants ranged in age from 10 to 15 years, with a mean age of 12.2 years; 64.2% were White, 24.0% Black, 5.8% Hispanic, and 6.0% other races. White and Hispanic youth and youth of other races had significantly higher rates of smoking than did Black youth. Significant risk factors for smoking were: higher grade in school, White race, and for girls only, lower self-esteem. In White youth those in the lowest socioeconomic status were most likely to be current and experimental smokers. Smoking was as common in girls as in boys at these ages. Multivariate analysis showed that neither physical activity nor parental smoking were significant predictors of smoking behaviors. These results suggest that smoking prevention programs for adolescents should specifically target White and Hispanic youth and those from families with low socioeconomic status. In addition, these interventions should include ways to increase self-esteem in girls.

Targeting signal 1 through CD45RB synergizes with CD40 ligand blockade and promotes long term engraftment and tolerance in stringent transplant models

The induction and maintenance of allograft tolerance is a daunting challenge. Although combined blockade of CD28 and CD40 ligand (CD40L)-costimulatory pathways prevents allograft rejection in some murine models, this strategy is unable to sustain engraftment in the most immunogenic allograft and strain combinations. By targeting T cell activation signals 1 and 2 with the novel combination of anti-CD45RB and anti-CD40L, we now demonstrate potent enhancement of engraftment in C57BL/6 recipients that are relatively resistant to costimulatory blockade. This combination significantly augments the induction of tolerance to islet allografts and dramatically prolongs primary skin allograft survival. Compared with either agent alone, anti-CD45RB plus anti-CD40L inhibits periislet infiltration by CD8 cells, B cells, and monocytes; inhibits Th1 cytokines; and increases Th2 cytokine expression within the graft. These data indicate that interference with activation signals one and two may provide synergy essential for prolonged engraftment in situations where costimulatory blockade is only partially effective.

[Analysis of main chemical composition in hydrogenated rosin from Zhuzhou]

The acid fraction, the main part of the hydrogenated rosin produced by Zhuzhou Forest Chemicals Plant of China, was separated from neutral fraction by modified DEAE-Sephadex ion exchange chromatography and analyzed with GC-MS-DS technique by using DB-5 capillary column. Six dihydroabietic-type resin acids, four dihydropimaric/isopimaric-type resin acids and four tetrahydroabietic-type resin acids were identified. The hydrogenated rosin is composed mainly of 8-abietenoic acid, 18-abietanoic acid, 13-abietenoic acid, 8 alpha, 13 beta-abietanoic acid, 13 beta-8-abietenoic acid and 8-isopimarenoic acid etc.

Changes in common activities of 3rd through 10th graders: the CHIC study

PURPOSE

This study was a longitudinal examination of the change in both the activities done and the intensity of those activities from childhood to adolescence.

METHODS

Common activities were assessed by questionnaire initially on 656 subjects from 21 elementary schools; 50.5% were female, 83.4% were Caucasian, 20.6% African-American, and 6.0% were other races.

RESULTS

Girls more often reported sedentary activities overall. Weighted least squares analyses showed boys consistently reported more vigorous activities than girls (P < 0.0008). African-American girls reported fewer vigorous activities than Caucasian or other race girls (P = 0.027). Sedentary activities were more frequently reported with increasing age (X2 P < 0.001). The youngest African-American and Caucasian boys reported similar activity patterns. However, boys from other races reported more intense activities until sixth and seventh grades when African-American boys began reporting more sedentary activities than Caucasians or other races (P = 0.004). During sixth-eighth grades, Generalized Estimating Equations (GEE) models show that girls with more advanced pubertal status reported more sedentary activities than girls who were less developed (P < 0.0001). For high school girls, race was a marginally significant predictor (P = 0.05) of activity status. Neither race nor pubertal status were significant factors in activities chosen by middle school boys. However, for male high school students, Caucasians were more likely than African-Americans to report vigorous activities (P = 0.005).

CONCLUSIONS

Variation in activities by race within gender suggests that establishing activity patterns in youth may be race-specific as well as gender-specific and must be accounted for in designing physical activity interventions. Also, pubertal maturation is a factor in activity choices in middle school girls.

[Bioproductivity of Castanopsis hysrix-Cyclobalanopsis glauca-Machilus pauhoi community in Huitong, Hunan]

Based on the mean DBH measurements of sample trees, the bioproductivity of subtropical Castanopsis hysrix-Cyclobalanopsis glauca-Machilus pauhoi community in Huitong, Hunan province was studied by regression analysis (y = a(D2.H)b). The results showed that the total biomass of the forest was 451.02 t.hm-2, and the component biomass of tree, shrub, liana and litter layer was 426.76, 17.76, 1.80 and 4.70 t.hm-2, respectively. The net production and average production of tree layer were 34.46 and 13.32 t.hm-2.yr-1, respectively.

Animal models in xenotransplantation

The severe shortage of donor organs has provided a strong impetus to push the investigation into the use of animal organs for humans. Xenotransplantation will not only benefit patients, but also represents a unique and potentially profitable business opportunity. However, there are many barriers to successful clinical xenotransplantation, including immunological barriers, physiological incompatibility, zoonosis and ethical concerns. This overview will focus on currently available animal models used in attempts to break through the immunological barriers to xenotransplantation. There are many advantages to using small animal, namely rodent, models in xenotransplantation research. For example, the use of the mouse model allows the use of knockout mice and careful dissection of rejection mechanisms at the molecular level. The following models can be used to study hyperacute rejection (HAR): guinea-pig-to-rat, mouse-to-rabbit, guinea-pig-to-mouse, rat-to-presensitised mouse and rat-to-alpha-Gal knockout mouse. The hamster-to-rat, mouse-to-rat and rat-to-mouse models are commonly used to study acute vascular rejection. Large animal models are complex and expensive, but they are more relevant to clinical xenotransplantation. Based on experiments using transgenic pig-to-primate models, HAR can be overcome. However, acute vascular rejection remains a major barrier at the present time. A pig cartilage-to-monkey model has been developed to study chronic rejection. Other novel models such as pig venous segment-to-monkey model and rat-to-primate model may represent viable options to study immunological barriers following xenotransplantation. Like many other medical breakthroughs, animal research will continue to make enormous contributions towards the eventual success of xenotransplantation.

[Analysis of the factors related to the change of energy expenditure in burned patients]

OBJECTIVE

To analyze the factors related to the change of energy expenditure in burned patients.

METHODS

Indirect calorimetry was employed to detect energy expenditure (EE) dynamically in 45 cases of burned patients and to analyze their change.

RESULTS

EE increased immediately postburn and reached top level in about one week (11, 443.78 plus minus 3, 295.32) kJ/d. EE value was positively correlated to the size of burn area. EE was also correlated to the development of the disease. The EE variation happened in the early postburn stage. The degree of variation was positively correlated to the size of burn area. The EE value in patients with medium size burn and inhalation injury was higher than that without inhalation injury. Postoperative EE decreased obviously in patients with major burn who had undergone escharectomy. EE in male patients was higher than that in female.

CONCLUSION

Postburn EE varied with some regularity, but was affected by burn depth and size, postburn time, inhalation injury, escharectomy, sex and individual difference.

Reduced NO production improves early canine islet xenograft function: a role for nitric oxide in islet xenograft primary nonfunction

Isolated canine islets transplanted to hyperglycemic rats fail to restore euglycemia in almost all cases, although the grafted islet tissue appears to be morphologically intact for up to 48 h following transplantation. Cytokines typically produced in the xenograft environment (e.g., IL-1 and TNF) inhibit insulin biosynthesis and secretion from isolated pancreatic islets, and are associated with the production of nitric oxide (NO). To further define the relationship between NO production and islet xenotransplantation, the inhibition of NO in a splenocyte/islet coculture system, and the in vivo effect of this inhibition on canine islet xenotransplantation, was investigated. Splenocytes (SPLC) from Lewis rats were cocultured with canine islets (freshly isolated or cultured 7 days), supernatant removed, and NO concentration (NO2) determined by optical density (Griess reaction, 550 nm, expressed as nmol nitrite/10(6) cells/18 h). Lipopolysaccharide (LPS) was used as a positive control of SPLC production of NO. Stimulation by LPS resulted in maximal NO production (2.20 +/- 0.16 nmol/10(6) cells/18 h, p < 0.001 compared to baseline values of 0.73 +/- 0.04 nmol/10(6) cells/18 h). In the presence of NO inhibitors (NMA, polymyxin B, hydrocortisone, aminoguanidine, DMSO), nitrite levels did not significantly rise above unstimulated values. Freshly isolated canine islets did stimulate NO production (1.26 +/- 0.12 nmol/10(6) cells/18 h, p < 0.001). In contrast, cultured canine islets did not stimulate NO production (0.84 +/- 0.09 nmol/10(6) cells/18 h). Transplantation of freshly isolated canine islets to STZ-diabetic recipient Lewis rats resulted in amelioration of hyperglycemia in only 50% (n = 6) of recipients 12 h posttransplant, with a return to hyperglycemia at all subsequent time points. Transplantation of 7-day cultured canine islets resulted in amelioration of hyperglycemia in 88% of recipients 12 h posttransplant and 63% of recipients 24 h posttransplant [p = 0.028, mean survival time (MST) = 1.0 days, n = 8]. Transplantation of canine islet xenografts with aminoguanidine therapy (BID, n = 11) resulted in amelioration of hyperglycemia in 100% of recipients at 12 h posttransplant, decreasing to 82% by 24 h following transplantation (p = 0.002, MST = 0.9 days). These results demonstrate that freshly isolated canine islets are potent stimulators of NO production by rat SPLC in vitro, and that culture of canine islets, or addition of NO inhibitors, abrogates stimulated NO production. These results also demonstrate a statistically significant improvement (p < 0.001) in early function of canine islet xenografts following 7 days of islet culture prior to transplant, and following recipient treatment with aminoguanidine. These studies suggest that the production of NO in the microenvironment of the graft site may adversely affect engraftment and function of canine islets, and suggest that the abrogation of islet-stimulated NO production may improve engraftment following islet xenotransplantation.

Cardiovascular disease risk factors and obesity of rural and urban elementary school children

Previous studies on the influence of a rural/urban setting on the prevalence of cardiovascular disease risk factors in children have not sufficiently controlled for socioeconomic status, race, gender, and perhaps, may not have included a representative sample of rural and urban children. This study compared the cardiovascular disease risk factors and rate of obesity of children living in rural and urban settings. It also determined the magnitude of the effect of the rural/urban setting on cardiovascular disease risk factors and obesity when controlling for race, socioeconomic status, and gender. The subjects were 2,113 third- and fourth-grade children; 962 from an urban setting and 1,151 from a rural setting. Height, weight, skinfolds, resting blood pressure, and total cholesterol levels were measured. Aerobic power (pVO2max) was estimated from cycle ergometry. Physical activity and smoking history were obtained from a questionnaire. Clustering analyses using adjustment for sample error indicated that total cholesterol, blood pressure, smoking, and physical activity levels of rural and urban children were not different (P > 0.10); however, body mass index and sum of skinfolds was greater for rural youth (P < 0.004). Logistic regression indicated that rural children had a 54.7 percent increased risk of obesity (P = 0.0001). This study's results indicate that, in children, a rural setting is associated with obesity, but not with the major risk factors associated with cardiovascular disease.

The axis of interleukin 12 and gamma interferon regulates acute vascular xenogeneic rejection

Recent advances using transgenic animals or exogenous complement inhibitors have demonstrated prevention of hyperacute rejection of vascularized organs, but not graft loss due to acute vascular rejection. Using various wild-type and cytokine-deficient mice strains, we have examined the mechanisms of acute vascular rejection. C57BL/6 mice deficient in interleukin12 or gamma interferon showed faster acute vascular rejection than did wild-type mice. Furthermore, mice defective in B-cell development showed no acute vascular rejection. These results demonstrate that the axis of interleukin 12 and gamma interferon provides a survival advantage in vascularized xenografts by delaying or preventing acute vascular rejection caused by a B cell-dependent mechanism.

The influence of physical activity, socioeconomic status, and ethnicity on the weight status of adolescents

OBJECTIVE

This study examined the effects of physical activity, television viewing, video game play, socioeconomic status (SES), and ethnicity on body mass index (BMI).

RESEARCH METHODS AND PROCEDURES

The sample was 2389 adolescents, 10 to 16 years of age (12.7 +/- 1.0 years); 1240 (52%) females and 1149 (48%) males; 77% white and 23% African American; from rural (77%) and urban (23%) settings. BMI and skinfolds were directly assessed. All other data were obtained from questionnaires.

RESULTS

Watching television on non-school days was related to being overweight (p < 0.005). However, when BMI analyses were adjusted for ethnicity and SES, there were no significant effects of television viewing on BMI (p > 0.061). Increased hours of video game play enhanced the risk of being overweight for both genders when analyses were adjusted for ethnicity and SES (p < 0.019). In males, participation in as little as one high-intensity physical activity 3 to 5 days a week decreased the ethnic- and SES-adjusted relative risk of being overweight (RR = 0.646; CI: 0.427 to 0.977). For females, the ethnic- and SES-adjusted relative risk for being overweight was not significantly altered by physical activity. The logistic analyses further indicated the influence of low SES and African American ethnicity overshadowed any direct effect of television or videos.

DISCUSSION

Because weight status of male adolescents appears to be more related to exercise habits than to television or video game habits, increased participation in high-intensity exercise appears to be important. For females, neither videos nor exercise habits appear to be related to risk of being overweight. However, ethnicity and SES may be important factors that can influence body weight status, while television viewing may be of some importance. Thus, programs to reduce obesity in female adolescent should focus their efforts in lower SES communities.

[Mechanism of recombinant human growth hormone accelerating burn wound healing in burn patients]

OBJECTIVE

To investigate the mechanism of recombinant human growth hormone (rhGH) in acceleration of burn wound healing.

METHODS

Thirty three severe burn patients were enrolled in this study and randomly divided into rhGH group (n = 18) and placebo control group (n = 15). The rhGH was administered subcutaneously in the dose of 0.1 mg . kg(-1) at 10 pm every evening in rhGH group for 14 days, while normal saline was used as a placebo in the control group. The serum concentration of GH and IGF-1 were assayed with ELISA method, and the proliferation index (PI) and S-phase fraction (SPF) of wound tissue was analyzed by flow cytometry (FCM). The expression of PCNA, EGFR and CK was assessed by immunohistochemical stains.

RESULTS

Serum concentrations of GH and IFG-1 increased significantly after rhGH administration. The PI and SPF of wound tissue were obviously higher than those before rhGH administration and those in the control group. The expressions of PCNA, EGFR and CK was enhanced. In addition, the epidermis of healed wound was thicker in rhGH group than that in the control group.

CONCLUSION

The application of rhGH in burn patients could improve the serum concentration of GH and IFG-1, promote DNA synthesis and PCNA and EFGR expression of epithelium, so that re-epithelialization of the burn wound could be accelerated.

[Mixing of Cunninghamia lanceolata with Michelia macclurei and restoration of self-sustaining mechanism in G. lanceolata plantation]

The formation of self-sustaining mechanism is one of the major objectives for the sustainable management of plantations. In this study, the incorporation of different proportions of native Michelia macclurei into Cunninghamia lanceolata plantation was practiced to restore the degraded C. lanceolata plantation, and the comparison of nutrient cycling characteristics and soil nutrient concentrations was made among four types of plantation stand with different mixed rate of native M. macclurei representing four different restoration stages of degraded C. lanceolata plantations. With the increase of the proportion of M. macclurei in the plantation, the litterfall and returned nutrients N, P, K, Ca and Mg increased. The nutrient cycling efficiency increased significantly, e.g., that of N and Mg increased from about 0.1 for the degraded pure C. lanceolata plantation to above 0.5 for the pure M. macclurei plantation. Soil organic matter and nutrients also elevated. It is suggested that the self-sustaining mechanism of the C. lanceolata plantation forest gradually reformed as the proportion of native M. macclurei mixed in the plantation increased. The criteria to determine the proportion of native broad-leaved tree species mixed in C. lanceolata plantations for the purpose of sustainable management should be based on whether the self-sustaining mechanism was reformed and whether the soil nutrient status was improved.

Smokeless tobacco use in adolescents: the Cardiovascular Health in Children (CHIC II) Study

Smokeless tobacco has seen a resurgence of popularity among adolescents despite its association with oral cancer and altered cardiovascular function. This study examined age, gender, ethnicity, self-esteem, physical activity, parental smoking, and socioeconomic status as predictors of smokeless tobacco use among middle school children. Subjects included 1,211 youth (White (64%), Black (24%), Hispanic (6%), and Other (6%); age 12.2) participating in the Cardiovascular Health in Children and Youth (CHIC II) study. All data were collected by questionnaire. Factors related to ever using smokeless tobacco included older age (p < .001), being male (p < .001), lower self-esteem (p < .001), and having parents who currently (p = .02) or formerly (p = .05) smoked. Hispanics reported a higher current usage rate than other ethnic groups (p < .001). White youth in the lowest socioeconomic status were most likely to be experimental users (p = .007), while those in the high socioeconomic status were more likely to be current users (p = .006). Physical activity was not associated with smokeless tobacco use.

Gene therapy strategies to facilitate organ transplantation

Organ transplantation is now the definitive therapy for many forms of end-organ disease, but chronic allograft rejection, the side effects of chronic immunosuppressive therapy and the severe donor organ shortage continue to limit its success. Gene therapy has the potential to prevent graft rejection by manipulating the immune response in the microenvironment of the graft or by facilitating the induction of tolerance. Genetic manipulation of stem cells to create transgenic and/or knockout animals that could serve as organ or cell donors could be combined with gene therapy approaches to overcome the problem of limited allogeneic donor organ supply.

[Study on the determination of aluminum in soil samples by air-acetylene flame atomic absorption spectrometry]

This paper reported a method for the direct determination of aluminum in soil samples by air-acetylene flame atomic absorption spectrometry. The enhancement effect on aluminum of adding tetramethylammonium chloride was studied. 43 microg/mL/1% of characteristic concentration was reached. This method is simple, rapid and useful, and has been applied to the determination of aluminum in standard soil samples, and a good agreement was achieved.

[Fiberoptic bronchoscopy in diagnosis and treatment of inhalation injury]

OBJECTIVE

To explore the morphological standard of diagnosing inhalation injury, the feasibility of early diagnosis and the topical therapy of inhalation injury through fiberoptic bronchoscopy.

METHODS

In one hundred and forty four patients with inhalation injury that were admitted in 10 years were examined with bronchoscopy, and the results were analysed.

RESULTS

Diagnostic criteria and classification were obtained with the aid of the bronchoscopy. It was found feasible to make early diagnosis within 8 h and also to exercise treatments in the form of suction, irrigation, etc.

CONCLUSION

Bronchoscopy plays an important role in the early diagnosis and treatment of inhalation injury, and it should be used more extensively in patients suspected to have inhalation injury.

Synthesis of three diosgenyl saponins: dioscin, polyphyllin D, and balanitin 7

Dioscin, polyphyllin D, and balanitin 7, which belong to a group of structurally similar diosgenyl saponins with promising bioactivities, were synthesized by stepwise glycosylation.

[Polymorphisms of five short tandem repeat systems in Chinese Han population in Chengdu]

OBJECTIVE

To get preliminary genotype and allele frequency distributions of D6S366, D6S477, D12S375, D12S391 and PLA2A loci in Chinese Han population in Chengdu area and to validate more short Tandem repeat (STR) systems for forensic application.

METHODS

The polymerase chain reaction (PCR) was used. Five STR systems (D6S366, D6S477, D12S375, D12S391 and PLA2A) were amplified on DNA samples, which were extracted from 108 unrelated individuals EDTA-blood by Phenol/Chloroform method. The PCR products were analyzed by PAG vertical electrophoresis.

RESULTS

Seven alleles were found at D6S366 locus, nine alleles at D6S477 locus, five alleles at D12S375 locus, nine alleles at D12S391 locus and seven alleles at PLA2A locus. No deviations from Hardy-Weinberg equilibrium were observed. The heterozygosities observed were 0.69, 0.78, 0.81, 0.68 and 0.79 for D6S366, D6S477, D12S375, D12S391 and PLA2A respectively. The chances of exclusion were 0.3621, 0.6004, 0.4581, 0.7014 and 0.5589 and the discriminating powers were 0.79, 0.93, 0.86, 0.96 and 0.91.

CONCLUSION

All of the five loci in this study were useful markers for individual identification and paternity test and for genetics purposes.

[The percentage of free prostate specific antigen used in detecting prostate cancer]

OBJECTIVE

To evaluate the value of the percentage of free prostate specific antigen in detecting prostate cancer.

METHODS

Serum free prostate specific antigen (F-PSA) and total PSA were measured with immunoradiometric assay, and the free/total PSA ratio was calculated. In 117 patients, 31 had prostate carcinoma and 86 BPH.

RESULTS

The free/total PSA ratio was lower in patients with prostate cancer than in those with BPH. If the total serum PSA level was limited with in 4 - 10 ng/ml, the free/total PSA ratio can be used in the differential diagnosis of prostate cancer and BPH except total PSA.

CONCLUSIONS

The free/total PSA ratio can be used in the differential diagnosis of prostate cancer and BPH, especially when serum PSA level is limited with in 4 - 10 ng/ml.