Biomedical subjects

C R Li

Publications and source records attributed to C R Li.

At least 19 recordsLinked to original sources

PubMed2004

Refined localization of dyschromatosis symmetrica hereditaria gene to a 9.4-cM region at 1q21-22 and a literature review of 136 cases reported in China.

BACKGROUND: Dyschromatosis symmetrica hereditaria (DSH) is an autosomal dominant pigmentary genodermatosis characterized by hyperpigmented and hypopigmented macules on the extremities, which has recently been mapped to an 11.6-cM interval on chromosome 1q11-21. So far, most cases of DSH have been reported in Japan and dermatologists around the world might think this disorder mainly occurs in Japan. In fact, there are 17 DSH families including 136 cases reported in China since 1980, but most of them are described in Chinese. OBJECTIVES: To refine the previously mapped region that facilitates the identification of the DSH gene and to delineate the clinical and genetic features of Chinese DSH cases by a literature review of 136 cases reported in China. METHODS: We performed genotyping and linkage analysis using polymorphic microsatellite markers at 1q11-22 in two Chinese DSH families, and reviewed all of the DSH cases reported in China since 1980. RESULTS: A cumulative maximum two-point lod score of 3.68 was produced with marker D1S506 at a recombination frequency of theta = 0.00 in these two families. Haplotype analysis refined the DSH locus to a 9.4-cM interval flanked by D1S2343 and D1S2635. The genetic and clinical features of Chinese cases with DSH were summarized. In some Chinese cases, hyperpigmented and hypopigmented macules were scattered on the neck and chest, but among Japanese patients there were no similar skin lesions to be reported on these sites. CONCLUSIONS: This study confirms linkage of DSH to a previously mapped region and refines the DSH gene to a 9.4-cM interval at 1q21-22. Likewise, the literature review indicates that DSH is not an uncommon disorder in China and the differences in the distribution of skin lesions could be related to race and environment.

Adult↗

PubMed2003

A new glycine substitution mutation in the COL7A1 gene in a Chinese family with dominant dystrophic epidermolysis bullosa.

Dystrophic epidermolysis bullosa (DEB) is caused by mutations in the COL7A1 gene encoding type VII collagen, the major component of anchoring fibrils. The characteristic genetic lesion in dominant DEB (DDEB) is a glycine substitution in the collagenous domain of the protein. In this study, we identified a Chinese family with a four-generation pedigree of DDEB, in whom a novel glycine substitution mutation in COL7A1 was demonstrated. A heterozygous nucleotide G-->A transition at position 6208 in exon 74 of COL7A1 was detected, which resulted in a glycine to arginine substitution (G2070R) in the triple-helical domain of type VII collagen. This substitution was not found in 110 unrelated normal alleles. This report emphasizes the predominance of glycine substitution mutations in DDEB and contributes to the expanding database on COL7A1 mutations.

Adolescent↗

PubMed2001

Effect of intravenous immunoglobulin on inhibiting peripheral blood lymphocyte apoptosis in acute Kawasaki disease.

UNLABELLED: This study aimed to explore the therapeutic mechanism of intravenous immunoglobulin (IVIG) for Kawasaki disease (KD). Peripheral blood lymphocytes (PBLs) obtained from 26 children with KD and 20 age-matched healthy children were stimulated with anti-CD3 monoclonal antibody (mAb), and the percentage of apoptotic cells and DNA fragmentation were assayed at 0, 12, 24, 48 and 72 h in vitro. The patients were divided into two groups: one treated with aspirin combined with IVIG (n = 16) and one treated with aspirin alone (n = 10). PBLs were stimulated by phytohaemagglutinin to evaluate the lymphocyte proliferative response. Compared with normal controls, the apoptotic cell percentage and the DNA fragmentation were markedly decreased (p < 0.001) and delayed in PBLs from KD patients. After IVIG treatment, the decreased percentage of apoptotic cell and delayed DNA fragmentation were restored to the state of the normal controls, accompanied by a fast clinical remission compared with the aspirin-alone group. The lymphocyte proliferative response was also decreased 3-5 d after IVIG therapy (p < 0.001). CONCLUSION: The results suggest that decreased PBL apoptosis may be involved in the pathogenesis of KD. The therapeutic mechanism of IVIG in KD may be partially due to the reversal of the inhibited lymphocyte apoptosis, and may have implications for other autoimmune diseases with inefficient lymphocyte apoptosis.

Apoptosis↗

PubMed2000

Impairment of motor imagery in putamen lesions in humans.

Patients with putamen or cortical lesions participated in a first- and third-person movement imagery task, each primarily engaging kinesthetic and visual imagery. The subjects were instructed to imagine themselves (first-person task) and a third party (third-person task) performing a sequence of three movements and to choose from a set of four photos the end posture resulting from the movements. The results demonstrated that, limb-specific imagery was impaired in both putamen and cortical lesions, in the first-, but not third-person task. Moreover, more than half of the errors made by cortical patients were with respect to the first movement, a finding consistent with motor cortex involvement in memory processes. Taken overall, the results provide evidence that the basal ganglia as well as cortical structures play an important role in the neural network mediating motor imagery.

Cerebral Infarction↗

PubMed2000

[Epidemiologic survey of dental fluorosis and caries in school students in Wensu county in Xinjiang].

OBJECTIVE: To assess the relationship between the dental fluorosis and caries,and their prevalence features in school students in Wensu country in Xinjiang. METHODS: The study groups consisted of 1527 Weuer and Han students at the age of 6 to 16. Dental fluorosis and caries disease were assessed strictly by Dean's Classification Standard and WHO "Oral Health Surveys Basic Methods" (the 3rd ed). The concentration of fluorine in water and urine was measured by using selective electrode. RESULTS: The prevalence and index of dental fluorosis in Weuer and Han students were 73.70%, 64.67%, 1.647, 1.303,respectively. The prevalence of dental caries and DMFT were 61.19%, 42.66%, 1.648, 1.023 respectively. The corresponding values were 51.94%, 52.99%, 1.305, 1.449 for students of fluorosis group and non-fluorosis group, respectively. The fluorine degree of water was 2-5mg/L,the average value of fluorine in urine was 3.64 mg/L in Han students, and 5.28 mg/L in Weuer students. CONCLUSION: The prevalence of dental caries didn't decrease, even though the grevalence of fluorosis was high in Weuer country. The prevalence of fluorosis dental caries in Weuer students were significantly higher than those in Han students. It showed no significant different between the group of fluorosis and the group of non-fluorosis in the prevalence of dental caries, perhaps due to the high fluorine intake, poor oral hygiene, and unqualified medical service.

English Abstract↗

PubMed1997

[Synthesis and antifungal activities of 1-(1-substitutedphenyl)-2-(1H-1,2,4-triazol or benztriazol-1-yl)-O-(substitutedbenzyl) ethanoximes].

Twenty-nine 1-(1-substituted phenyl)-2-(1H-1,2,4-triazol or benztriazol-1-yl)-O-(substituted benzyl) ethanoximes have been synthesized for the first time. Results of preliminary biological test in vitro show that most compounds have antifungal activities against most fungi tested. The antifungal activities of compounds T1, T4, T6, T11, T12, B1, B3, B4 and B6 are better than or comparable to the activities of the lead compound oxiconazole against some fungi.

Antifungal Agents↗

PubMed1994

Recovery of HLA-restricted cytomegalovirus (CMV)-specific T-cell responses after allogeneic bone marrow transplant: correlation with CMV disease and effect of ganciclovir prophylaxis.

Protection from cytomegalovirus (CMV) disease in immunocompromised hosts has been shown to correlate with recovery of the host virus-specific CD8+ T-cell response. The administration of ganciclovir to immunosuppressed transplant recipients as antiviral prophylaxis has reduced the early risk of CMV disease, but late disease is observed with increased frequency, suggesting that recovery of the CMV-specific T-cell responses necessary for protective immunity may be delayed in these patients. Therefore, we evaluated reconstitution of CMV-specific T-cell responses in 47 bone marrow transplant (BMT) recipients entered on a randomized placebo-controlled study of ganciclovir. The study drug was initiated at a mean of 24 days after BMT. At day 30 to 40, a minority of patients had recovery of T-cell immunity to CMV and the frequency of reconstitution was equivalent in patients randomized to ganciclovir or placebo. The failure of ganciclovir to effect early reconstitution may reflect the short duration of treatment. Early recovery was associated with the infusion of BM from a CMV seropositive donor (P = .07 for CD8+ cytotoxic T cell (CTL), P = .04 for CD4+ Th). Between day 40 and day 90, recovery of deficient CD8+ and CD4+ CMV-specific T-cell responses occurred in the majority of individuals that received placebo, but in a minority of ganciclovir recipients. Two cases of late-onset CMV disease occurred in ganciclovir recipients. In all patients, the presence of a CTL response to CMV conferred protection from subsequent CMV disease (P = .005), and these protective CTL responses are shown to be specific for structural virion proteins similar to the responses in immunocompetent CMV seropositive individuals. These data confirm the importance of CMV-specific T-cell responses and suggest that a delay in recovery of these responses as a result of ganciclovir prophylaxis may contribute to the occurrence of late CMV disease.

Adolescent↗

PubMed1994

Identification of the major late human cytomegalovirus matrix protein pp65 as a target antigen for CD8+ virus-specific cytotoxic T lymphocytes.

Primary cytomegalovirus (CMV) infection and reactivation of persistent CMV are associated with significant morbidity and mortality in immunocompromised individuals. Although recovery from CMV disease is correlated with the development of CMV-specific cytotoxic T lymphocytes (CTL), the major viral target antigens to which the response is directed are ill-defined, though they may comprise viral structural elements. We now identify the CMV matrix protein pp65 as a significant target antigen for CD8+ class I major histocompatibility complex (MHC)-restricted CMV-specific CTL derived from the peripheral blood of four of five latently infected individuals. CMV-specific CTL recognition of pp65 on target cells occurs prior to the onset of viral gene expression and persists throughout the duration of the replicative cycle. Recognition in the absence of viral gene expression suggests that abundant viral protein enters the normal trafficking pathway upon viral penetration and is readily made available to MHC molecules for presentation at the cell surface. Thus pp65 specific CTL may represent an important effector population for early control and limitation of CMV infection and disease. The observation that CMV-specific CTL can be induced in vitro using peptide fragments derived from pp65 supports the future use and manipulation of this and similar effector populations in a clinical setting.

Antigens, Viral↗

PubMed1993

Selective interference with class I major histocompatibility complex presentation of the major immediate-early protein following infection with human cytomegalovirus.

Responses of cytotoxic T-cells (Tc) to human cytomegalovirus (CMV) represent the predominant mechanism by which hosts resist CMV infection. The CMV major immediate-early protein (IE) is present throughout the virus replicative cycle. Studies were performed to determine whether Tc specific for IE effectively lyse CMV-infected targets and are thus capable of providing protective immunity against infection. After in vitro stimulation of peripheral blood mononuclear cells with CMV-infected autologous fibroblasts, Tc specific for IE were not readily detectable in CMV-reactive polyclonal Tc lines. However, after stimulation of peripheral blood mononuclear cells with cells selectively expressing IE, weak but detectable IE-specific Tc responses were observed. The frequency of IE-specific Tc clones derived from cultures stimulated with IE-expressing cells was 50 to 100 times lower than the frequency of Tc clones specific for other CMV proteins isolated from cultures stimulated with CMV-infected cells. All of the IE-specific Tc clones, which efficiently lysed targets selectively expressing IE, demonstrated minimal lysis of CMV-infected fibroblasts, despite abundant IE expression in these target cells. In contrast to these results with IE, other viral proteins were efficiently presented during all phases of CMV infection. These data suggest that CMV has evolved a unique mechanism for selectively limiting the presentation of the potentially immunogenic IE protein, which may preclude IE-specific Tc from providing protective immunity to CMV infection.

Antigen-Presenting Cells↗

PubMed1993

Immunologic abnormalities in children with acute Kawasaki disease.

Spontaneous release of IgG, production of IgG, IgM and IgG subclasses induced by PWM in vitro, serum IgG, IgM, IgA and IgG subclasses were measured in 23 patients with acute Kawasaki disease (KD). The results showed that there was polyclonal B cell activation with significantly increased IgG1 and IgG3. As compared with 21 healthy controls, the mean activities of B cell growth factors (BCGFs), B cell differentiation factors (BCDFs) and interleukin 6 (IL-6) were significantly elevated. IL-6 activity was correlated with the production of IgG, IgG1, IgG3 and IgM, while BCGFs and BCDFs were also correlated with IgG1. The serum level of circulating tumor necrosis factor (TNF) determined in 16 patients with acute KD using double antibody ELISA was 1.86-8.83 micrograms/ml, but it was less than 1 microgram/L in normal controls. The clinical value of increased TNF in serum is discussed.

Child↗

PubMed1992

Restoration of viral immunity in immunodeficient humans by the adoptive transfer of T cell clones.

The adoptive transfer of antigen-specific T cells to establish immunity is an effective therapy for viral infections and tumors in animal models. The application of this approach to human disease would require the isolation and in vitro expansion of human antigen-specific T cells and evidence that such T cells persist and function in vivo after transfer. Cytomegalovirus-specific CD8+ cytotoxic T cell (CTL) clones could be isolated from bone marrow donors, propagated in vitro, and adoptively transferred to immunodeficient bone marrow transplant recipients. No toxicity developed and the clones provided persistent reconstitution of CD8+ cytomegalovirus-specific CTL responses.

Antigens, Differentiation, T-Lymphocyte↗

PubMed1991

Immunoglobulin G subclass deficiency in children with recurrent respiratory tract infections.

With monoclonal antibodies serum immunoglobulin G(IgG) subclasses were measured in seventy children aged 2 to 13 years with recurrent respiratory tract infections including upper respiratory tract infections, otitis media, sinusitis, asthmatic bronchitis and pneumonia. 211 healthy, aged-matched children served as control. IgG subclass deficiency was found in 19 out of the 70 patients (27.1%, single IgG1 deficiency in 7, IgG2 deficiency in 4, combined IgG1-IgG3 deficiency in 5, IgG1-IgG2-IgG3-IgG4 deficiency, IgG1-IgG2-IgG4 deficiency and IgG2-IgG4 deficiency each in 1). The incidence of IgG subclass deficiencies was in the sequence as follows: IgG1, 20%; IgG2, 10%; IgG3, 8.6% and IgG4, 4.3%. The results suggest that IgG subclass deficiency indicate a common disorder in children with recurrent respiratory tract infections.

Adolescent↗

PubMed1990

Immunoglobulin G subclasses in serum and circulating immune complexes in patients with Kawasaki syndrome.

IgG subclass concentrations in sera of 17 patients with Kawasaki syndrome were determined. Significantly increased IgG1 (P less than 0.001) and IgG3 (P less than 0.001) were found in the patients compared with 22 age-matched healthy children, whereas IgG2 and IgG4 were normal or slightly decreased. IgG immune complexes were measured by protein A-enzyme-linked immunosorbent assay (ELISA) combined polyethylene glycol precipitations. Eight of 17 patients (47.1%) were found to have circulating immune complexes (CIC) values above the normal control range (geometric mean +2 SD). IgG subclass composition in CIC was analyzed. The subclasses in CIC were predominantly IgG1 and IgG3. Because the antibody responses to different antigens exhibit IgG subclass restriction, it would suggest that the change of serum and CIC IgG subclasses in Kawasaki syndrome may have relevance to the pathogenesis of the disease.

Antigen-Antibody Complex↗

PubMed1989

[IgG subclasses in the serum and circulating immune complexes in patients with Kawasaki disease].

IgG subclass levels in sera of 17 patients with Kawasaki disease were determined and a significant increase of IgG 1 (P less than 0.001) and IgG 3 (P less than 0.001) was found in the patients compared with 22 age-matched healthy children, while IgG 2 and IgG 4 were normal or slightly decreased. IgG immune complexes were measured by SPA-ELISA combined with PEG precipitations, and 8 out of 17 patients (47.1%) were found to have CIC values above the normal control range (geometric mean +2 SD). IgG subclass composition in CIC was analysed. The subclasses in CIC were predominantly in IgG 1 and IgG 3. Because the antibody responses to different antigens have IgG subclass restriction. These results suggest that the change of serum and CIC IgG subclasses in Kawasaki disease may be related to the pathogenesis of the disease.

Antigen-Antibody Complex↗

PubMed1987