Low agreement between the T-SPOT®.TB assay and the tuberculin skin test among college students in China

T-SPOT®.TB and the tuberculin skin test (TST) were used to screen for latent tuberculosis infection among 899 Chinese college students. The positivity rates for T-SPOT®.TB and TST were respectively 13.0% (95% confidence interval [CI] 10.4-15.9) and 24.9% (95%CI 21.5-28.6) among students with a bacille Calmette-Guérin (BCG) scar (agreement of both tests 72.3%; 95%CI 68.6-75.8; κ = 0.118), and respectively 17.3% (95%CI 11.7-24.2) and 23.7% (95%CI 17.3-31.2) among those without a BCG scar (agreement 73.1%; 95%CI 65.4-79.9; κ = 0.179). These results demonstrate low agreement between the TST and T-SPOT.TB in the Chinese population studied.

Prophylaxis against hepatitis B recurrence posttransplantation using lamivudine and individualized low-dose hepatitis B immunoglobulin

Although the combination of lamivudine (LAM) and high-dose intravenous (IV) hepatitis B immunoglobulin (HBIG) is very effective in preventing hepatitis B virus (HBV) recurrence after liver transplantation (LT), the major limitation of this regimen is its high cost. A more cost-effective, convenient and widely accepted regimen is urgently needed. We evaluated the safety and efficacy of another strategy using LAM and individualized low-dose intramuscular (IM) HBIG. Between May 2002 and December 2009, a total of 254 adult patients undergoing LT for HBV-related benign end-stage liver diseases received this regimen in our center. The mean follow-up of these patients was 41.2 +/- 22.7 months. Their 1-, 3- and 5-year survival rates were 85.3%, 77.4% and 76.4%, respectively, and 1-, 3- and 5-year HBV recurrence rates were 2.3%, 6.2% and 8.2%. Fourteen patients experienced posttransplant HBV recurrence. Pretransplant high viral load and posttransplant prednisone withdrawal time were observed to be associated with recurrence. In conclusion, combination therapy with LAM and individualized low-dose IM HBIG provides a safe and effective prophylaxis against HBV recurrence after LT at about 5% of the cost of conventional high-dose IV HBIG regimens.

Radiosensitization effect of luteolin on human gastric cancer SGC-7901 cells

The radiosensitizing effects of luteolin were studied in the gastric cancer cell line SGC-7901. SGC-7901 cells were treated with luteolin or/and irradiation, and radiosensitizing effects were assessed by colony-forming assay with cells and nude mice. In order to study the underlying mechanism, the levels of apoptosis-related proteins, the activities of caspase-3 and -9, and the production of PGE2 were measured. The results showed that luteolin could enhance irradiation-induced colonogenic inhibition and the activities of Caspase-3 and -9. The remarkable down-regulation of Bcl-2 and release of cytochrome C were also observed. In addition, significantly reduced production of PGE(2) was observed in luteolin plus radiation treatment by ELISA, as well as decreased expression levels of VEGF and HIF-1 alpha. Finally, luteolin significantly enhances the radioresponse of human tumors transplanted into nude mice. Our results indicate that luteolin may be a promising radiosensitizer for use in the treatment of gastric cancer.

Gender-related differences in quality of life domains of persons living with HIV/AIDS in South India in the era prior to greater access to antiretroviral therapy

This study sought to examine gender-based differences in the quality of life of men and women living with HIV in South India in the era prior to greater access to antiretroviral therapy. The participants in this prospective longitudinal study consisted of 215 men and 141 women who were administered a quality of life (QOL) instrument comprising five scales: physical well-being, psychosocial well-being, sexual well-being, satisfaction with health care, and strength of partner relationship. Interviews were conducted at enrollment and at 6 months in clinical care. Men and women reported similar scores in physical well-being, satisfaction with health care, and relationship with partner from the period prior to care, at enrollment, and at 6 months. Women scored significantly lower than men in psychosocial well-being from the period prior to care, at enrollment, and at 6 months (p < 0.05); women reported significantly higher levels of partner satisfaction at 6 months (p < 0.05). In light of the increasing feminization of the HIV epidemic in India, greater emphasis should be placed on examining the long-term experiences of Indian women living with HIV/AIDS, particularly their psychosocial well-being.

Effect of a holiday service reduction period on a hospital's emergency department access block

OBJECTIVE

To study the effect of holiday service reductions, consisting of bed and theatre closures, in a tertiary paediatric hospital on various measures of ED occupancy, including access block.

METHODS

Retrospective comparative observational study of all 2142 ED attendances during a holiday hospital service reduction period (the 'study period'), when the hospital's bed capacity was reduced by 17% and all elective operating theatres were closed, and all 4255 attendances during two control periods at a major tertiary children's hospital, using the ED's information system to collect data. The following outcome measures were derived from the raw data and compared between the control and study groups: proportion of all intended inpatient admissions that were actual inpatient admissions; proportion of intended inpatient admissions that were discharged home from the ED; proportion of all admissions that were ED admissions; access block, that is, the percentage of patients requiring inpatient admission who have a total ED time of greater than 8 h; the mean number of patients in the ED at any particular minute ('ED occupancy'); median waiting times to reach both the general ward and the operating theatre.

RESULTS

There were no statistically significant differences between the study group and the control group in all of the outcome measures except for access block, which showed a 16% relative improvement (49.8-41.7%) during the study period when compared with the control period (P < 0.01).

CONCLUSION

At this hospital, unacceptably high levels of ED access block persist both during and outside holiday periods, despite there being mild improvement in access block during the holiday period where bed closures were balanced against the effect of other service cutbacks (e.g. closing operating theatres).

Association of HLA genes with ankylosing spondylitis in Han population of eastern China

Ankylosing spondylitis (AS) is a chronic inflammatory disorder with a multifactorial genetic basis. HLA-B27 was reported with the greatest susceptibility to AS but did not act alone. The aim of this study was to search for other gene(s) associated with AS independently of HLA-B27 using 13 microsatellite markers spanning 1.5 Mb from locus TAP1 to HLA-Cw and a single-nucleotide polymorphism marker within NFkappaBIL1 gene promoter. Genotyping for microsatellites was performed in 175 AS patients of eastern Chinese and 219 ethnically matched healthy controls using polymerase chain reaction with fluorescence-labelled primers, whereas the SNP marker was genotyped by direct DNA sequencing. Allele as well as haplotype frequencies were compared between cases and controls, and a linkage disequilibrium analysis was performed to estimate the LD relationship between the candidate regions. The frequencies of alleles D6S2811*128, STR_MICA*A5.1 and D6S2672*109, as well as haplotypes D6S2811*128-D6S2927*213-D6S2810*340, D6S2927* 221-D6S2810*350-MICA*A5.1, and D6S2810*350-MICA*A5.1-D6S2800* 136 were significantly increased in B27-positive AS patients when compared with B27-positive controls. The results indicated that there may be other gene(s) within the HLA region, especially around locus HLA-B or HLA-Cw, with susceptibility to AS independently of HLA-B27.

Airway resistance variability and response to bronchodilator in children with asthma

Variability of airway function is a feature of asthma, spanning timescales from months to seconds. Short-term variation in airway resistance (R(rs)) is elevated in asthma and is thought to be due to increased variation in the contractile activation of airway smooth muscle. If true, then variation in R(rs) should decrease in response to bronchodilators, but this has not been investigated. Using the forced oscillation technique, R(rs) and the variation in R(rs) from 4-34 Hz were measured in 39 children with well-controlled mild-to-moderate asthma and 31 healthy controls (7-13 yrs) before and after an inhaled bronchodilator (200 microg salbutamol) or placebo. In agreement with other findings, baseline R(rs) at all frequencies and the sd of R(rs) (R(rs) sd) below 14 Hz were found to be elevated in asthma while neither forced expiratory volume in one second nor the mean forced expiratory flow between 25 and 75% of forced vital capacity were different compared with controls. The present authors found that R(rs) sd changed the most of any measurement in asthma, and this was the only measurement that changed significantly more in children with asthma following bronchodilator administration. The present results show that like airway narrowing, short-term airway variability of resistance may be a characteristic feature of asthma that may be useful for monitoring response to therapy.

Epitope diversity of hepatitis B virus capsids: quasi-equivalent variations in spike epitopes and binding of different antibodies to the same epitope

To investigate the range of antigenic variation of HBV capsids, we have characterized the epitopes for two anti-capsid antibodies by cryo-electron microscopy and image reconstruction of Fab-labeled capsids to approximately 10A resolution followed by molecular modeling. Both antibodies engage residues on the protruding spikes but their epitopes and binding orientations differ. Steric interference effects limit maximum binding to approximately 50% average occupancy in each case. However, the occupancies of the two copies of a given epitope that are present on a single spike differ, reflecting subtle distinctions in structure and hence, binding affinity, arising from quasi-equivalence. The epitope for mAb88 is conformational but continuous, consisting of a loop-helix motif (residues 77-87) on one of the two polypeptide chains in the spike. In contrast, the epitope for mAb842, like most conformational epitopes, is discontinuous, consisting of a loop on one polypeptide chain (residues 74-78) combined with a loop-helix element (residues 78-83) on the other. The epitope of mAb842 is essentially identical with that previously mapped for mAb F11A4, although the binding orientations of the two monoclonal antibodies (mAbs) differ, as do their affinities measured by surface plasmon resonance. From the number of monoclonals (six) whose binding had to be characterized to give the first duplicate epitope, we estimate the total number of core antigen (cAg) epitopes to be of the order of 20. Given that different antibodies may share the same epitope, the potential number of distinct anti-cAg clones should be considerably higher. The observation that the large majority of cAg epitopes are conformational reflects the relative dimensions of a Fab (large) and the small size and close packing of the motifs that are exposed and accessible on the capsid surface.

Diversity of core antigen epitopes of hepatitis B virus

Core antigen (cAg), the viral capsid, is one of the three major clinical antigens of hepatitis B virus. cAg has been described as presenting either one or two conformational epitopes involving the "immunodominant loop." We have investigated cAg antigenicity by cryo-electron microscopy at approximately 11-A resolution of capsids labeled with monoclonal Fabs, combined with molecular modeling, and describe here two conformational epitopes. Both Fabs bind to the dimeric external spikes, and each epitope has contributions from the loops on both subunits, explaining their discontinuous nature: however, their binding aspects and epitopes differ markedly. To date, four cAg epitopes have been characterized: all are distinct. Although only two regions of the capsid surface are accessible to antibodies, local clustering of the limited number of exposed peptide loops generates a potentially extensive set of discontinuous epitopes. This diversity has not been evident from competition experiments because of steric interference effects. These observations suggest an explanation for the distinction between cAg and e-antigen (an unassembled form of capsid protein) and an approach to immunodiagnosis, exploiting the diversity of cAg epitopes.

Characterization of a conformational epitope on hepatitis B virus core antigen and quasiequivalent variations in antibody binding

We have characterized a conformational epitope on capsids of hepatitis B virus (HBV) by cryo-electron microscopy and three-dimensional image reconstruction of Fab-labeled capsids to approximately 10-A resolution, combined with molecular modeling. The epitope straddles the interface between two adjacent subunits and is discontinuous, consisting of five peptides-two on one subunit and three on its neighbor. Together, the two icosahedral forms of the HBV capsid-T=3 and T=4 particles-present seven quasiequivalent variants of the epitope. Of these, only three bind this Fab. Occupancy ranges from approximately 100 to approximately 0%, reflecting conformational variations in the epitope and steric blocking effects. In the former, small shifts of the component peptides have large effects on binding affinity. This approach appears to hold general promise for elucidating conformational epitopes of HBV and other viruses, including those of neutralizing and diagnostic significance.

Association of the HLA A2-B46-DR9 haplotype with autoimmune thyroid dysfunction after bone marrow transplantation in Chinese patients

Autoimmune thyroid disease (AITD) may occur in patients after bone marrow transplantation (BMT). At a median follow-up of 4 years, among 194 allografts and 28 autografts, four patients (three allografts, one autograft) developed AITD. All carried the human leucocyte antigen (HLA) A2-B46-DR9 haplotype, strongly associated with AITD in the Chinese population. No significant thyroid disorder was detected in 190 patients without this haplotype. The frequency of AITD in BMT patients with the HLA A2-B46-DR9 haplotype was 12.5%, with a relative risk of 7.8 times that of non-carriers (P < 0.001). The risk of AITD should be recognized in recipients with high-risk HLA haplotypes, and regular screening might be warranted.

Risk of haematological malignancies in HLA-B27 carriers

Human leucocyte antigen (HLA)-B27 carriers are predisposed to inflammatory and autoimmune diseases. Among 1137 patients with haematological diseases, 59 HLA-B27 carriers were identified. Compared with 18 774 volunteers, the incidence of HLA-B27 was increased in patients with acute leukaemia (relative risk RR = 1.67, P = 0.002), for both acute myeloid leukaemia (AML) (RR) = 1.67, P = 0.007) and acute lymphoblastic leukaemia (ALL) (RR = 1.68, P = 0.094). Of all the HLA-B27 carriers, four patients had ankylosing spondylitis (AS), all with lymphoid malignancies (three ALL, one Hodgkin's disease), whereas no HLA-B27 carriers with myeloid leukaemia had AS symptoms (P = 0.006). This suggests that HLA-B27 carriers may have an increased risk of acute leukaemia and those with concomitant AS may be predisposed to lymphoid malignancies.

Beta-helix model for the filamentous haemagglutinin adhesin of Bordetella pertussis and related bacterial secretory proteins

Bordetella pertussis establishes infection by attaching to epithelial cells of the respiratory tract. One of its adhesins is filamentous haemagglutinin (FHA), a 500-A-long secreted protein that is rich in beta-structure and contains two regions, R1 and R2, of tandem 19-residue repeats. Two models have been proposed in which the central shaft is (i) a hairpin made up of a pairing of two long antiparallel beta-sheets; or (ii) a beta-helix in which the polypeptide chain is coiled to form three long parallel beta-sheets. We have analysed a truncated variant of FHA by electron microscopy (negative staining, shadowing and scanning transmission electron microscopy of unstained specimens): these observations support the latter model. Further support comes from detailed sequence analysis and molecular modelling studies. We applied a profile search method to the sequences adjacent to and between R1 and R2 and found additional "covert" copies of the same motifs that may be recognized in overt form in the R1 and R2 sequence repeats. Their total number is sufficient to support the tenet of the beta-helix model that the shaft domain--a 350 A rod--should consist of a continuous run of these motifs, apart from loop inserts. The N-terminus, which does not contain such repeats, was found to be weakly homologous to cyclodextrin transferase, a protein of known immunoglobulin-like structure. Drawing on crystal structures of known beta-helical proteins, we developed structural models of the coil motifs putatively formed by the R1 and R2 repeats. Finally, we applied the same profile search method to the sequence database and found several other proteins--all large secreted proteins of bacterial provenance--that have similar repeats and probably also similar structures.

An epidemiological survey of cystic echinococcosis among Tibetan school pupils in West China

Human cystic echinococcosis (CE) caused by infection with a larval stage of Echinococcus granulosus is a serious public health problem in West China. Because CE is a zoonosis, dogs and livestock are important hosts in transmission. Tibetans, especially teenagers, have a natural relationship with these definitive and intermediate hosts in West China and although some areas of Tibet are therefore CE-endemic, few, if any, detailed community studies have been reported. A total of 451 Tibetan school pupils living in rural Tianzhou County in Gansu Province in West China were investigated by mass ELISA and IHA with ultrasound scanning back-up, and positivity rates were found to be 9.5% and 1.6%, respectively, with 0.98% confirmation of hepatic CE in four asymptomatic cases. Seropositivity rates varied with age between 6.2% and 13.2%. IHA found that females had a significantly greater risk of infection than males, a ratio of about 3:1. Age-specific immunopositive rates increased from 6.2% in the 8-13-years age group to 13.2% in those aged over 18. The study found that keeping dogs and herding animals had no effect on rates of infection but that the number of sheep owned by a family correlated with infection rates. The rate of infection in people who hunted was significantly higher than in those who did not. Level of education was found to have no effect on rates of infection.

[Expression of KDR in medulloblastoma and its clinical implication]

OBJECTIVE

To gain an insight into the possible relationship between the expression of kinase insert domain-containning receptor (KDR) and the prognosis of medulloblastoma.

METHODS

Fifty cases of medulloblastoma of the posterior fossa and ten cases of normal cerebellar tissue were studied via a combination of immunnohistochemical staining in formalin fixed paraffin-embedded sections.

RESULTS

KDR was expressed weakly in 1 of 10 normal cerebellar tissues, while KDR was either moderately or strongly expressed in most of the medulloblastomas (49 of 50 cases). Moreover, KDR was expressed not only in the endothelial cells of tumor vasculature, but also in tumor cells. Correlation analysis indicated that expression of KDR was correlated significantly with survival time (r = -0.527, P < 0.01).

CONCLUSION

KDR was expressed in most of the medulloblastomas, not only in the endothelial cells of tumor vasculature, but also in tumor cells. The expression level of KDR had a negative correlation with the survival time, thus it might be used as one of the prognosticators of medulloblastoma.

[A study of adhesion molecule expression in extraocular muscles of Graves' ophthalmopathy]

OBJECTIVE

To investigate the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular adhesion molecule-1 (VCAM-1) in extraocular muscles (EOM) of the eyes with Graves' ophthalmopathy (GO).

METHODS

Seventeen EOM specimens obtained from 16 severe patients with GO and their cryostat sections were observed by double labeling immunohistochemical methods.

RESULTS

The expression of ICAM-1 was observed in interstitial and perimysial connective tissue surrounding EOM fibers, mononuclear cells, fibroblasts and vascular endothelial cells. Only were vascular endothelial cells stained for VCAM-1, and ICAM-1 and VCAM-1 immunoreactivities were not detected in EOM cells.

CONCLUSIONS

The findings indicate that ICAM-1 and VCAM-1 might be involved in the development of GO, and fibroblasts, vascular endothelial cells and mononuclear cells might play important roles in the autoimmune reaction.

[Reduction of FHIT gene expression in primary lung cancer: relationship with the proliferation and apoptosis of tumor cell]

OBJECTIVE

To investigate the role of FHIT(fragile histidine triad) gene in oncogenesis and progression of human lung cancer and explore the relationship of FHIT gene expression with the proliferation and apoptosis of tumor cells.

METHODS

The expression of FHIT gene and that of Ki-67 were detected in 166 lung cancer samples and 37 lung benign lesion tissues as control by immunohistochemistry, and the apoptotic level of tumor cell was detected by terminal deoxynucl neotidyl transferase mediated dUTP nick end labelling(TUNEL).

RESULTS

(1)The expression level of FHIT gene was found to be significantly lower in lung cancer tissues than in benign lesion tissues (P<0.01); (2)The expression level of FHIT gene was closely related to histological classification, cancer cell differentiation, P-TNM stages and lymph node involvement in lung cancer patients (P<0.05); (3)Lasting and heavy smoking might be one of the important reasons of reduction of FHIT gene expression in lung cancer patients; (4)The postoperative survival time of patients in high FHIT expression group was significantly longer than those in low expression group (P<0.05); (5)The reduction of FHIT gene expression might be related with the over-proliferation and suppression of apoptosis of lung cancer cell(P<0.01).

CONCLUSION

FHIT gene may play a role in the regulation of proliferation and apoptosis of lung cancer cell. And reduction of FHIT gene expression may be related to the pathogenesis and development of lung cancer.

[Expression of apoptosis of the skin lesion and muscle from patients with dermatomyositis]

OBJECTIVE

This study inquired into the relationship between the influence of corticosteroid and the expression of apoptosis, Fas and Bcl-2 in muscle from patients with dermatomyositis (DM).

METHODS

Corticosteroid was given to group A (10 DM cases) but not given to group B (12 DM cases).

RESULTS

Apoptotic cells were detected in situ by terminal deoxynucleotidyl transferase-mediated-dUTP nick end labeling (TUNEL). Fas and Bcl-2 expressions was determined with the use of immunohistochemical staining in DM. The results showed that more expression of apoptosis in keratinocytes, muscle cells and lymphocytes were observed in group A. The apoptotic index (AI) of muscle cells and that of lymphocytes were more marked in group A than in group B (P < 0.05). Less apoptosis cells were observed in two weeks of treatment, and no correlation was found between apoptosis and the lesion of skin and muscle.

CONCLUSION

The authors suggest that corticosteroid may play a role in inducing the apoptosis of keratinocytes, muscle cells and lymphocytes, which may be one of the therapeutic mechanisms of corticosteroid. The length of administering corticosteroid to the patients seems related to apoptosis.