BACKGROUND: Type Ⅱ collagen has been used as the carrier for chondrocyte transplantation in animal models, but whether type Ⅱ collagen may cause arthritis or mediate cytotoxicity remains unknown.OBJECTIVE: To detect the cellular immune functions of the New Zealand rabbits immunized by porcine type Ⅱ collagen.DESIGN: An exploratory comparative study based on the observations.SETTING: An institute of trauma surgery of a municipal hospital.MATERIALS: The study was conducted in the Institute of Trauma Surgery,Guangzhou Red Cross Hospital from August 1999 to February 2000. Six New Zealand rabbits, whose body mass ranged from 2.0 kg to 3.0 kg, were chosen of either gender.METHODS: The rabbits were immunized by porcine type Ⅱ collagen for 60days, during which the plasma was regularly taken for detection of type Ⅱ collagen antibody. On the 60th day, the peripheral blood as well as the spleens and lymph nodes were taken to separate the lymphocytes, which were subjected to secondary stimulation with type Ⅱ collagen in vitro to observe the reactive cell proliferation. The lymphocytes were randomly divided into two groups, and the first group was treated with phytohemagglutinin(PHA) of different concentrations to serve as the positive control, in which non-specific immunity was examined; The second group was treated with type Ⅱ collagen of different concentrations for examining specific immunity.peripheral blood lymphocytes of normal and immunized rabbits.RESULTS: On the 21st day, the titer of the antibody presented the first peak, and 40 days after the re-injection of the antigen the second peak appeared, which maintained for 20 days and then gradually descended. The lymphocytes of the normal rabbits proliferated in response to PHA stimulation but not to the first stimulation with the type Ⅱ collagen. The lymphocytes of the immunized rabbits exhibited significant proliferation upon stimulations with both PHA and type Ⅱ collagen. At the concentration of 25 mg/L, type Ⅱ collagen stimulation was sufficient to induce lymphocyte proliferation, the peak of which occurred when the collagen concentration reached 50 mg/L.CONCLUSION: Xenogenic type Ⅱ collagen at an adequate concentration may induce the increase of the type Ⅱ collagen antibody in immunized rabbits and proliferation of lymphocytes of the spleens and peripheral blood to cause cellular immune reaction and even immunological arthritis in relation to the transplantation.

Objective: To reveal the molecular epidemiologic characteristics of glucose-6-phosphate dehydrogenase (G6PD) gene and to evaluate based on the genetic analysis the newborn screening program performance and enzymatic diagnosis of G6PD deficiency in Guangzhou. Methods: G6PD enzyme activities were measured by quantitative fluorescence assay in dry blood spots of 16 319 newborns(8 725 males, 7 594 females) 3-7 days after birth in Guangzhou Newborn Center. They were born in Guangzhou form Oct. 1 to 20, 2016. The cutoff value of G6PD was less than 2.6 U/g Hb in dry blood spots. G6PD deficiency was diagnosed when G6PD<1 700 U/L or G6PD/6PGD<1 in red blood cells. Genetic analysis of G6PD gene was performed on the dry blood spot samples of 823 newborns (including positive 346, negative 477)with various levels of G6PD enzyme activities through fluorescence PCR melting curve analysis(FMCA) to detect 15 kinds of mutations reported to be common among Chinese.G6PD gene Sanger sequency was performed in seven highly suspicious patients with negative results by FMCA. Results: (1) Using the cutoff value of G6PD< 2.6 U/g Hb , a total of 687(4.2%) newborns showed positive screening results, including 560 (6.4%) males and 127(1.7%) females. (2) Among the newborns with positive screening results, 214 males and 122 females were randomly chosen for G6PD gene analysis. The results showed that 197 (92.1%) males were hemizygote and 108(88.6%) females were mutation carriers with one to four alleles. Among the newborns with negative screening results, 41 males with G6PD 2.6-2.8 U/g Hb and 436 females with G6PD 2.6-4.5 U/g Hb were chosen for genetic analysis.Mutations were detected in 5(12.2%)boys, and 226(51.8%) girls were carriers.G6PD gene Sanger sequency of seven highly suspicious patients showed that c.406C>T, c.551C>T, c.835A>T hemizygote were found in 3 male's samples, respectively. (3) The estimated prevalence of harboring mutation was 6.0% in males and 13.5% in females according to rates of mutation in samples with various levels of G6PD enzyme activities. Six common mutations were c.1388G>A、c.1376G>T, c.95A> G, c.871G>A, c.1024C>T, c.392G>T, accounting for 95.5% of detected alleles .(4) based on results of G6PD gene analysis, the newborn scereening of G6PD deficiency with cutoff value G6PD<2.6 U/g Hb yielded a positive predict value(PPV) of 93.5%, a false-positive rate of 0.5%, and a sensitivity of 99.0% for males. A PPV of 88.5%, a false-positive rate of 0.2% . The prevalence of severe type G6PD deficiency in females was about 1.5%. Compared with to genetic analysis, the sensitivity and PPV of G6PD activity assay in red blood cells were 95.5%, 97.2%, respectively. Conclusions The prevalence of G6PD deficiency in males was 6.0% in Guangzhou. Six mutations c.1388G>A, c.1376G>T, c.95A>G, c.871G>A, c.1024C>T, c.392G>T accounted for 95.5%. The cutoff value of G6PD<2.6 U/g Hb innewborn screening program and the criteria of biochemical diagnosis could accurately identify G6PD deficiency . Combined with biochemical and molecular analysis will improve the accuracy of diagnosis of G6PD deficiency and detect more heterozygous females.

OBJECTIVETo compare the photosynthetic characteristics of Notopterygium incisum and N. forbesii in order to provide basic data for introduction and cultivation of the two wild medicinal species.

METHODThe light-response, CO2-response and Chlorophy II fluorescence parameters of leaves at the booting stages between N. incisum and N. forbesii, were analyzed in situ by Li-6400 Portable Photosynthesis system under natural conditions.

RESULT1) The light saturation point (LSP) was 1539 micromol x m(-2) x s(-1) for N. incisum and 1464 micromol x m(-2) x s(-1) for N. forbesii, the maximum net photosynthetic rate (Pmax) was 22.95 micromol x m(-2) x s(-1) for N. incisum and 19.65 micromol x m(-2) x s(-1) for N. forbesii, the apparent quantum yield (AQY) was 0.0509 for N. incisum and 0.0470 for N. forbesii, LSP, AQY and Pmax of N. incisum were significantly higher than those of N. forbesii; the light compensation point (LCP) was 17.92 micromol x m(-2) x s(-1) for N. incisum and 26.69 micromol x m(-2) x s(-1) for N. forbesii, LCP of N. incisum was significantly lower than that of N. forbesii. 2) The carbondioxide compensation point (CCP) were 33.41 micromol x mol(-1) for N. incisum and 37.82 micromol x mol(-1) for N. forbesii, the carbon dioxide saturation point (CSP) were 988 micromol x mol(-1) for N. incisum and 1150 micromol x mol(-1) for N. forbesii, CCP and CSP of N. incisum were significantly lower than N. forbesii; the carboxylation efficiency (CE) were 0.0591 for N. incisum and 0.0459 for N. forbesii; the maximum rate of RuBP regeneration (Jmax) were 28.18 micromol x m(-2) x s(-1) for N. incisum and 25.32 micromol x m(-2) x s(-1) for N. forbesii; the light respiration rate (Rd) were 1.971 micromol x m(-2) x s(-1) for N. incisum and 1.736 micromol x m(-2) x s(-1) for N. forbesii, CE, Jmax and Rd of N. incisum were higher than those of N. forbesii. 3) The primary light energy conversion of PS II (Fv/Fm) was 0.8213 for N. incisum and 0.8257 for N. forbesii, wihich didn't showed significant difference, between N. incisum and N. forbesii there was no photoinhibition.

CONCLUSIONBoth N. incisum and N. forbesii were C3 type plant, could perfectly acclimate to light condition. However, the weak light of N. incisum was absorbed significantly higher than that of N. forbesii, strong photosynthesis ability causes assimilation products accumulation of N. incisum obviously to be higher than that of N. forbesii.

Apiaceae ; drug effects ; metabolism ; radiation effects ; Carbon Dioxide ; pharmacology ; Dose-Response Relationship, Drug ; Dose-Response Relationship, Radiation ; Kinetics ; Light ; Photosynthesis ; drug effects ; radiation effects ; Plants, Medicinal ; drug effects ; metabolism ; radiation effects

To detect the cellular immunity state of New Zealand white rabbit immunized by pig type II collagen. The New Zealand white rabbit was immunized by type II collagen for sixty days. The plasma was collected at a regular interval and the anti-type II collagen antibodies were examined. At the sixtieth day, the peripheral circular lymphocytes and the lymphocytes separated from spleen cells of rabbit and lymph nodes were collected and were stimulated by type II collagen in vivo again. The regulation of reactive cellular proliferation caused by the stimulation was detected. The experiment samples were divided into two groups. The first group was the positive control group by adding different concentrations of PHA and the non-specific immunity was assayed. The different concentrations of type II collagen were added to the second group and the specific immunity was assayed. The lymphocytes of normal rabbits showed proliferation by PHA stimulation but no proliferation by the first stimulation of type II collagen. Obvious proliferation due to the stimulation of both PHA and type II collagen in the immunized rabbit were observed. It shows that certain concentration of heterogeneous collagen may cause an increase of anti-type II collagen antibody in immunized rabbit and may cause a proliferation of lymphocytes in rabbit spleen and peripheral blood. The heterogeneous type II collagen causes cellular immunity in vivo.
Animals ; Cell Division ; drug effects ; Collagen Type II ; administration & dosage ; immunology ; Cytotoxicity, Immunologic ; Female ; Histocompatibility Antigens ; Lymphocytes ; cytology ; immunology ; Male ; Rabbits ; Spleen ; cytology ; Swine ; Transplantation, Heterologous

Objective To study the influence of postnatal age and season of sample collection on congenital hypothyroidism (CH) screening and to determine the appropriate cut-off value. Method From January 2015 to December 2017, neonatal thyroid stimulating hormone (TSH) screening data in Guangzhou were retrospectively analysed. The infants were assigned into four groups according to sampling postnatal age:24～＜48 h, 48～＜72 h, 3～＜7＜d and≥7 d, and assigned into another four groups according to their birth seasons. Based on the data of 2015 and 2016, the cut-off value of TSH for hypothyroidism were adjusted. The data of 2017 were used to verify the accuracy of the adjusted cut-off value. The cut-off value was determined based on the receiver operating characteristic (ROC) curve and percentile method. Specificity, sensitivity, positive predictive value (PPV) and negative predictive value (NPV) of the cut-off value were also calculated. Result A total of 459854 newborns were screened from 2015 to 2016. 7329 were positive in preliminary screening, 371 were still positive after recall for re-examination, and 318 were confirmed with CH eventually. The optimal TSH cut-off value calculated using ROC curve was 9 mIU/L, with a percentage of 98.7. The cut-off value with sampling time≥48 h was set to 9 mIU/L in spring, summer and autumn, and 10 mIU/L in winter. The cut-off of sampling time 24～＜48 h was set to 10 mIU/L in all seasons. The data of 264993 newborns screened in 2017 were verified using the adjusted cut-off value. The overall positive rate was reduced from 1.27％to 1.02％, and the PPV was increased from 6.07％to 7.58％without adding false negative cases. Conclusion Adjusting cut-off values of TSH for CH screening according to postnatal age and season can effectively reduce false positive rates.

Objective: To explore the TPO, DUOX2 and DUOXA2 genotypes and phenotypes of children with permanent congenital hypothyroidism(PCH) suspected dyshormonogenesis in Guangzhou, identified and treated at Guangzhou Newborn Screening Center. Six of them were born between 2011 and 2012. Method: Retrospectively analyzed the clinical data of 9 children with PCH suspected dyshormonogenesis. Genetic analysis of TPO, DUOX2 and DUOXA2 genes were performed with Sanger sequencing. Result: Of the 9 patients, four were identified variants in TPO gene including three cases with biallelic variants and one case with monoallelic variant. Novel c. 1784G>C( p. R595T) variant in TPO was predicted to be damaging by SIFT and PolyPhen-2. Four patients harbored monoallelic known variants in DUOX2 gene and the other one harbored heterozygous known mutation c. 738C>G(p.Y246X) in DUOXA2 gene.Two adolescent patients with biallelic variants in TPO gene showed classical PCH phenotypes with thyroid goiter or nodules. The six patients with monoallelic variant in TPO, DUOX2 or DUOXA2 presented variable phenotypes. Among the 433 578 newborns in the 2011-2012 cohort, there were 156 cases of CH. Six of these cases were PCH suspected dyshormonogenesis, among which 1 case was confirmed TPO biallelic variants and 5 cases were monoallelic variants of TPO, DUOX2, or DUOXA2 genes. Conclusion TPO and DUOX2 variants are the common molecular pathogenesis in children with PCH suspected dyshormonogenesis. Monoallelic variants in TPO, DUOX2 or DUOXA2 are associated with PCH and showed wide variability in their phenotypes. The novel variant p. R595T in TPO is probably a pathologic variant. The prevalence of PCH caused by TPO gene defects is rare in Guangzhou.