Mobilising elementary and secondary school students for tuberculosis case finding in Anhui, China

OBJECTIVES

To evaluate the implementation of a FIDELIS (Fund for Innovative DOTS Expansion through Local Initiatives to Stop TB) project in Anhui Province, China.

DESIGN

A survey card was designed for students to identify individuals who might have tuberculosis (TB) in their family. Teachers provided health education on TB before distributing the survey cards. Survey cards identifying individuals with respiratory symptoms for ≥3 weeks were sent by the teachers to village doctors who were trained to visit symptomatic individuals and advise them to undergo sputum examination. Data were routinely collected in the implementation of the FIDELIS project, and quarterly reports from the National Tuberculosis Programme were analysed. The detection of new smear-positive TB cases before and after FIDELIS, as well as with and without FIDELIS, were compared.

RESULTS

In the first year, a total of 2 387 405 students were involved and 23 079 symptomatic individuals were examined, among whom 2307 (10.3%) were diagnosed with smear-positive TB. Case detection in FIDELIS counties increased by a factor of 3.5 during the FIDELIS period compared with before FIDELIS, and that in non-FIDELIS counties by a factor of 3.1 (P = 0.001).

CONCLUSION

It was feasible to massively mobilise students for TB case finding through collaboration between the health care and education systems.

Enhanced ultraviolet emission from Au/Ag-nanoparticles@MgO/ZnO heterostructure light-emitting diodes: A combined effect of exciton- and photon- localized surface plasmon couplings

Localized surface plasmon (LSP)-enhanced ultraviolet light-emitting diodes (LEDs) based on a Au/MgO/ZnO metal/insulator/semi- conductor heterostructure were fabricated by embedding Ag nanoparticles (Ag-NPs) into MgO dielectric layer. A ~6-fold electroluminescence (EL) enhancement was achieved from the Ag-NPs decorated device. Time-resolved spectroscopy studies, as well as analogue simulation and theoretical estimation based on experimental data, reveal that the internal quantum efficiency and light extraction efficiency of the heterojunction LED are increased ~3-fold and ~2-fold, respectively, as a result of the introduction of Ag LSPs. This result indicates that the observed EL enhancement originates from a combined effect of both exciton-LSP coupling and photon-LSP coupling.

Molecular characterization of Cryptosporidium spp. in pre-weaned calves in Shaanxi Province, north-western China

Cryptosporidium, a worldwide protozoan parasite, is one of the most common causes of diarrhoea in humans and animals. The aim of the present study was to determine Cryptosporidium species/genotypes in pre-weaned calves in Shaanxi Province using PCR and sequencing based on the small subunit rRNA gene. A total of 258 faecal samples were collected from pre-weaned calves in 19 different farms from six areas in Shaanxi Province, north-western China. Cryptosporidium infection was detected in 14 of 19 farms (73.7 %), with a total prevalence of 20.2 % (52/258). Both dairy and Qinchuan (beef) cattle were found with Cryptosporidium infection. Three Cryptosporidium species, namely Cryptosporidium bovis (n = 26), Cryptosporidium andersoni (n = 14) and Cryptosporidium ryanae (n = 12), were detected in pre-weaned calves in Shaanxi Province, with C. bovis (in 12 farms) identified as the most common species on cattle farms. Two additional and previously unknown C. ryanae genotypes, CRTypes III and IV, were observed in the present study. However, the zoonotic species, Cryptosporidium parvum, was not detected in this study, which suggested a low zoonotic potential in Cryptosporidium-infected pre-weaned calves in this province.

Improved methane production from waste activated sludge with low organic content by alkaline pretreatment at pH 10

Sludge with low organic content always results in an unsatisfactory performance, even failure of anaerobic digestion. The alkaline pretreatment effect on anaerobic digestion of sludge with low organic content has seldom been studied although it gives many benefits for sludge with high organic content. In this study the influence of alkaline pretreatment (pH 10, an effective alkaline pH) on the solubilization and methane production from waste activated sludge (WAS) with low organic content was investigated. Results from biochemical methane potential (BMP) experiments showed that anaerobic biodegradability of WAS was greatly improved by alkaline pretreatment at pH 10. Methane production from the current WAS under conditions of pretreatment time 4 h and digestion time 15 d was 139.6 mL/g VS (volatile solids), much higher than that from the unpretreated WAS with digestion time of 20 d (75.2 mL/g VS). Also, the solubilization of WAS was significantly accelerated by alkaline pretreatment. Mechanism exploration indicated that the general activities of anaerobic microorganisms, specific activities of key enzymes and the amounts of methanogens were enhanced by alkaline pretreatment at pH 10, showing good agreement with methane production.

First Report of Nigrospora oryzae Causing Leaf Spot of Cotton in China

Cotton (Gossypium hirsutum L.) is widely cultivated for the important economic value of the fiber. In the summer of 2011, a leaf spot of cotton plants cv. Wanza40 was observed in 11 fields (total of about 4 ha) in Qianshan County in southwest Anhui Province, China. Approximately 30% of the plants in each field were symptomatic. Affected plants exhibited brown to reddish, irregular foliar lesions, each with a brown border near the vein of the leaves. A sign of fungal infection was a dark leaf mold observed on lesions on the abaxial surface of leaves. Sections of symptomatic leaf tissues were surface-sterilized (in 75% ethanol for 30 s, then 1% NaOCl for 1 min), rinsed three times in sterile distilled water, and plated onto potato dextrose agar (PDA). A fungus consistently recovered from symptomatic leaf samples produced colonies that were initially white and then became grayish brown with the onset of sporulation. Black, spherical to subspherical, single-celled conidia (10 to 12 × 14 to 16 μm) were borne on a hyaline vesicle at the tip of each conidiophore. Morphological characteristics of the fungus were similar to that of Nigrospora oryzae (2). The internal transcribed spacer (ITS) region of ribosomal DNA (rDNA) from a representative strain of the fungus, AHC-1, was amplified using the primers ITS1/ITS4 (4) and sequenced (GenBank Accession No. JQ864579). The ITS sequence had 99% identity with >553 bp of the ITS sequence of an N. oryzae isolate (GenBank Accession No. EU918714.1). On the basis of morphological data and ITS rDNA sequence, the isolate was determined to be N. oryzae. A pathogenicity test was performed on detached, young leaves of 4-month-old healthy cotton plants of cv. Wanza40. Six leaves were inoculated by placing a colonized agar piece (5 mm in diameter) from 7-day-old cultures of the fungus on pushpin-wounded leaves. Another six leaves treated with sterile PDA plugs served as a negative control treatment. Leaves were incubated in petri dishes and maintained at 25°C in a growth chamber programmed for 12 hours of fluorescent white light/day. After 5 days, brown to black lesions were observed on all inoculated leaves, whereas no symptoms developed on control leaves. N. oryzae was consistently reisolated from symptomatic leaves but not from the control leaves. N. oryzae is a weak pathogen on a wide range of plants, and has been described as the causal agent of lint rot on cotton (1,3), but to our knowledge this is the first report of N. oryzae causing a leaf spot of cotton in China. References: (1) D. F. Farr and A. Y. Rossman. Fungal Databases, Systematic Mycology and Microbiology Laboratory, ARS, USDA, Retrieved from http://nt.ars-grin.gov/fungaldatabases/ , April 8, 2012. (2) H. J. Hudson. Trans. Br. Mycol. Soc. 46:355, 1963. (3) A. J. Palmatter et al. Plant Dis. 87:873, 2003. (4) T. J. White et al. In: PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, 1990.

[Clinical significance and detection of the expression of CD25- CD127- on CD4+ T cells in peripheral blood in patients with hepatitis B]

OBJECTIVE

To investigate the clinical significance and detection of the expression of CD25- CD127- on CD4+ T cells in peripheral blood in patients with hepatitis B.

METHODS

The expression of CD25- CD127- on CD4+ T cells were measured by using flow cytometry in 53 patients with chronic hepatitis B, 53 carrier with hepatitis B virus and 26 healthy blood donors, and follow up 20 patients with HBV-DNA positive treated with interferon.

RESULTS

(1) Compared with healthy controls, the expression of CD25- CD127- on CD4+ T cells in patients and carrier with hepatitis B virus were lower (Q = 4.559, P < 0.05; Q = 6.230, P < 0.05). (2) The expression of CD25- CD127- on CD4+ T cells in patients with HBV-DNA positive (n = 77) was lower than that of negative (n = 29) (t = 2.290, P = 0.024). (3) Compared with the prior treatment,the expression of CD25- CD127- on CD4+ T cells in patients with B hepatitis were lower after interferon treated with 12 weeks (t = 2.469, P = 0.024).

CONCLUSION

It suggested that the CD25- CD127- expression on CD4+ T cells correlated with viral infections and cleared,exogenous interferon could decrease CD25- CD127- expression on CD4+ T cells.

Changes in the proportions of CD4(+)T cell subsets defined by CD127 and CD25 expression during HBV infection

CD4(+)T cell counts are closely related to the progression of HBV infection. Here, we investigated how the proportions of three CD4(+)T cell subsets - CD127(-)CD25(-), CD127(+)CD25(low/-) and CD127(low)CD25(high) - changed during HBV infection, as is little known. Compared with healthy controls, the proportions of CD127(-)CD25(-) in chronic hepatitis B (CHB) patients and HBV carriers significantly increased, while that of CD127(+)CD25(low/-) significantly decreased. The proportion of CD127(low)CD25(high) in CHB patients was significantly higher than those in HBV carriers or healthy controls. Compared with HBV-DNA negative group, the proportion of CD127(-)CD25(-) in positive group significantly decreased and that of CD127(+)CD25(low/-) significantly increased. In the follow-up study for CHB patients treated with interferon-α2b for 12 weeks or 24 weeks, the proportions of CD127(-)CD25(-) significantly decreased, while that of CD127(low/-)CD25(high) significantly increased. The results suggested that specific changes in the fraction of CD4(+)T cell subsets expressing CD127 and/or CD25 were associated with hepatitis B progression.

First Report of Leaf Blight Caused by Nigrospora sphaerica on Curcuma in China

Curcuma (family Zingiberaceae) is commonly cultivated for the use of rhizomes within traditional Chinese medicines. In October 2009 and 2010, severe leaf blight was observed on Curcuma wenyujin Y.H. Chen & C. Ling (4) in fields located in Ruian, China. The area of cultivation in Ruian encompasses 90% of the production in Zhejiang Province. Disease incidence was approximately 90% of plants observed in affected fields. Early symptoms were yellow-to-brown, irregular-shaped lesions on the leaf margin or tip. After several days, lesions expanded along the mid-vein until the entire leaf was destroyed. Blighted leaves turned grayish to dark brown and withered, and severely affected plants died. Eight fungal isolates were recovered from symptomatic C. wenyujin leaves, collected from eight different fields, on potato dextrose agar (PDA). These fungal colonies were initially white, becoming light to dark gray and produced black, spherical to subspherical, single-celled conidia (14 to 17 × 12 to 15 μm), which were borne on a hyaline vesicle at the tip of the conidiophores. On the basis of these morphological features, the isolates appeared to be similar to Nigrospora sphaerica (2). Strain ZJW-1 was selected as a representative for molecular identification. Genomic DNA was extracted from the isolate, and the internal transcribed spacer (ITS) region of the ribosomal DNA (ITS1-5.8S-ITS2) was amplified using ITS1 (5'-TCCGTAGGTGAACCTGCGG-3') and ITS4 (5'-TCCTCCGCTTATTGATATGC-3') primers (3). The ITS region was further cloned and sequenced (GenBank Accession No. JF738028) and was 99% identical to N. sphaerica (GenBank Accession No. FJ478134.1). On the basis of morphological data and the ITS rDNA sequence, the isolate was determined to be N. sphaerica. Pathogenicity tests were conducted on four leaves of four C. wenyujin plants by placing agar pieces (5 mm in diameter) from 8-day-old cultures on pushpin-wounded leaves. An equal number of control plants were wounded and inoculated with noncolonized PDA agar pieces. Plants were placed in moist chambers at 25°C with a 12-h photoperiod. Brown-to-black lesions were observed on wounded leaves after 3 days and expanded to an average of 56 × 40 mm 15 days after inoculation. No symptoms developed on the control leaves. The pathogen was reisolated from the margins of necrotic tissues but not from the controls. The pathogen has been reported as a leaf pathogen on several hosts worldwide (1). To our knowledge, this is the first report of N. sphaerica as a leaf pathogen of C. wenyujin in China. Future research will focus primarily on management of this disease. References: (1) D. F. Farr and A. Y. Rossman. Fungal Databases, Systematic Mycology and Microbiology Laboratory, USDA-ARS, Retrieved from http://nt.ars-grin.gov/fungaldatabases/ , March 31, 2011. (2) E. W. Mason. Trans. Brit. Mycol. Soc. 12:152, 1927. (3) T. J. White et al. PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, 1990. (4) J. Zhao et al. Molecules 15:7547, 2010.

Differential gene expression and functional analysis of pit cells from regenerating rat liver

Hepatic pit cells are a population of large granular lymphocytes that substantially contribute to hepatic immunity. Studies have proven that pit cells have a role in liver regeneration, but the details of the relationship between pit cells and liver regeneration is not clear at present. We subjected rats to a two-third hepatectomy; pit cells with high purity were obtained with Percoll density centrifugation and immunomagnetic bead methods, and the changes in mRNA levels in pit cells from the regenerating liver were monitored up to 168 h using a Rat Genome 230 2.0 Array composed of 25,020 distinct rat liver cDNA clones. Of the 25,020 genes analyzed, 612 known and 358 unknown genes were identified to be associated with liver regeneration. The 612 known genes are classified into up-regulation and down-regulation patterns based on the expression levels; they primarily participate in at least 23 biological activities based on gene ontology analysis. Together with gene function enrichment analysis, cytokines and a growth factor-mediated pathway in pit cells were activated at an early phase of liver regeneration; pit cell proliferation occurred from 24-72 h after liver hepatectomy; the machinery of pit cell differentiation commenced early and came into play late; an immune/inflammatory response was enhanced late. Expression pattern analysis of functionally classified genes in pit cells can give insights into the relationship between pit cells and liver regeneration.

Emergy evaluation and economic analysis of three wetland fish farming systems in Nansi Lake area, China

Emergy and economic methods were used to evaluate and compare three fish production models, i.e., cage fish farming system, pond intensive fish rearing system and semi-natural extensive pond fish rearing system, in Nansi Lake area in China in the year 2007. The goal of this study was to understand the benefits and driving forces of selected fish production models from ecological and economic points of view. The study considered input structure, production efficiency, environmental impacts, economic viability and sustainability. Results show that the main difference among the three production systems was the emergy cost for fish feed associated with their feeding system, i.e., feeding on natural biomass such as plankton and grass or on commercial feedstock. As indicated by EYR, ELR and ESI, it can be clearly shown that the intensive production model with commercial feed is not a sustainable pattern. However, the point is that more environmentally sound patterns do not seem able to provide a competitive net profit in the short run. The intensive pond fish farming system had a net profit of 2.57E+03 $/ha, much higher than 1.27E+03 $/ha for cage fish farming system and slightly higher than 2.37E+03 $/ha for semi-natural fish farming system. With regard to the drivers of local farmer's decisions, the accessibility of land for the required use and investment ability determine the farmer's choice of the production model and the scale of operation, while other factors seem to have little effect. Theoretically, the development of environmentally sustainable production patterns, namely water and land conservation measures, greener feed as well as low waste systems is urgently needed, to keep production activities within the carrying capacity of ecosystems. Coupled emergy and economic analyses can provide better insight into the environmental and economic benefits of fish production systems and help solve the problems encountered during policy making.

Availability of second-line drugs and anti-tuberculosis drug susceptibility testing in China: a situational analysis

OBJECTIVE

To assess the availability of second-line drugs (SLDs) and the use of drug susceptibility testing (DST) results for the treatment of tuberculosis (TB) in China.

DESIGN

Cross-sectional survey in 4675 health care facilities, 1960 of which have a dedicated TB clinic, in 12 provinces in China.

RESULTS

More than 70% of TB clinics at the provincial and prefecture levels had at least one SLD available compared to 41.8% of facilities at the county/district level. The proportion of facilities at provincial, prefecture and county levels with any fluoroquinolone was respectively 74.1%, 64.9% and 34.5%. Sputum culture was performed at 6.0% of TB clinics at the county level, 37.5% at the prefecture and 59.3% at the provincial levels, while DST was performed only at the prefecture (28.6%) and provincial (44.4%) levels. Only 18% of the facilities that used SLDs for the treatment of multidrug-resistant TB (MDR-TB) based treatment regimens on DST results.

CONCLUSION

SLDs are widely available in China for the treatment of both TB and other infectious diseases. To prevent the development of Mycobacterium tuberculosis resistance to SLDs, the availability of SLDs should be limited and they should be used with caution in the treatment of MDR-TB.

Targeted deletion of NF-kappaB p50 diminishes the cardioprotection of histone deacetylase inhibition

We have recently demonstrated that the inhibition of histone deacetylases (HDAC) protects the heart against ischemia-reperfusion (I/R) injury. The mechanism by which HDAC inhibition confers myocardial protection remains unknown. The purpose of this study is to investigate whether the disruption of NF-kappaB p50 would eliminate the protective effects of HDAC inhibition. Wild-type and NF-kappaB p50-deficient mice were treated with trichostatin A (TSA; 0.1 mg/kg ip), a potent inhibitor of HDACs. Twenty-four hours later, the hearts were perfused in Langendorff model and subjected to 30 min of ischemia and 30 min of reperfusion. Inhibition of HDACs by TSA in wild-type mice produced marked improvements in left ventricular end-diastolic pressure, left ventricular rate pressure product, and the reduction of infarct size compared with non-TSA-treated group. TSA-induced cardioprotection in wild-type animals was absent with genetic deletion of NF-kappaB p50 subunit. Notably, Western blot displayed a significant increase in nuclear NF-kappaB p50 and the immunoprecipitation demonstrated a remarkable acetylation of NF-kappaB p50 at lysine residues following HDAC inhibition. EMSA exhibited a subsequent increase in NF-kappaB DNA binding activity. Luciferase assay demonstrated an activation of NF-kappaB by HDAC inhibition. The pretreatment of H9c2 cardiomyoblasts with TSA (50 nmol/l) decreased cell necrosis and increased in cell viability in simulated ischemia. The resistance of H9c2 cardiomyoblasts to simulated ischemia by HDAC inhibition was eliminated by genetic knockdown of NF-kappaB p50 with transfection of NF-kappaB p50 short interfering RNA but not scrambled short interfering RNA. These results suggest that NF-kappaB p50 acetylation and activation play a pivotal role in HDAC inhibition-induced cardioprotection.

VEGF gene therapy for the survival of transplanted fat tissue in nude mice

The objective of this study was to determine the effects of adenovirus-mediated vascular endothelial growth factor (Ad-VEGF) on the angiogenesis and survival of free-fat tissue transplantation in nude mice. Thirty 6-week-old CD-1 nude male mice were injected with 1ml fat tissue (harvested by suction-assisted lipectomy from the breast of humans) in the subcutaneous of scalp and were randomised into three groups of 10 animals each. Group 1 was the study group, in which Ad-VEGF was mixed with transplanted fat tissue and injected into mice. In group 2, adenovirus-mediated green fluorescent protein (Ad-GFP) gene was mixed with transplanted fat tissue and injected into the mice. In group 3, normal saline alone was used. Both group 2 and group 3 are control groups. The animals were euthanised 15 weeks after the procedure. The fat survival weight and volume of the study group were significantly greater than those of two control groups (p<0.05). Light microscopical examination of haematoxylin and eosin-stained slides of the dissected fat 15 weeks after injection was performed in group 1 and group 2. Less cyst formation and fibrosis, indicating improved quality of the injected fat, can be obtained by the addition of Ad-VEGF. Vascular density was evaluated at the microvascular level through the use of light microscopic sections of the central part of the fat tissue at 15 weeks after injection by von Willebrand factor staining. Histological evaluation showed that capillary density increased markedly in the study group mice. Mice of the study group disclosed significantly higher VEGF protein levels detected by ELISA assay of plasma samples obtained from the mice after the fat injection (day 1, 4, 7 and 28; p<0.01) at each time point than the mice of the two control groups. The findings reported in this study indicate that the VEGF gene therapy can enhance the survival and the quality of grafted fat tissue, which may be due to induction of angiogenesis.

The impact of migrants on the epidemiology of tuberculosis in Beijing, China

SETTING

Tuberculosis (TB) services in the Municipality of Beijing, China.

OBJECTIVE

To evaluate the impact of migrants on the epidemiology and management of TB in Beijing.

DESIGN

Comparison of information on permanent residents and migrants from routine reports of TB cases registered in Beijing from 1993 to 2005.

RESULTS

From 1993 to 2005, there was a steady rise in the proportion of migrants among TB cases notified in Beijing, from approximately one in 10 cases to one in three cases. The results of treatment in migrant cases of TB over the period 1997-2004 were unsatisfactory. The proportion of cases cured among permanent residents was 90.6%, compared with only 37.0% of cases among migrants.

CONCLUSION

Migrants pose a challenge to TB services in Beijing. Special attention must be given to them by the National Tuberculosis Programme to address these challenges.

[Induced expression of the variable region of AMA-1 from Plasmodium falciparum]

OBJECTIVE

To express the variable region of AMA-1 gene from Plasmodium falciparum in Escherichia coli.

METHODS

Genomic DNA of FCC1/HN was used as template and the variable region of AMA-1 gene was amplified by polymerase chain reaction(PCR). The PCR products were digested by endonuclease BamH I and Hind III, cloned into pBlu2KSP. The nucleotide sequences of the variable region of AMA-1 gene were determined by sequencing. The AMA-1 gene fragment was subcloned into plasmid pQE, expressed in E. coli and induced by IPTG. The fusion product as identified by SDS-PAGE gel electrophoresis and Western blotting were proceeded with anti-AMA-1 sera from rabbit.

RESULTS

The size of the variable region of AMA-1 gene from FCC1/HN was 506 bp and encoded 168 amino acids. On SDS-PAGE gel dyed with Coomassie brilliant blue R250, no specific protein band can be discerned, but Western blotting proceeded with anti-AMA-1 sera from rabbit demonstrated that the specific protein band was about 23.0 kDa.

CONCLUSION

The variable region of AMA-1 gene from FCC1/HN was able to be expressed in E. coli and analysis of Western blotting demonstrated that the AMA-1 fussion protein contained specific antigenic epitopes.

Thalidomide modulation of the immune response in female B6C3F1 mice: a host resistance study

Previously, we have reported that thalidomide (Thd) treatment can modulate the immune responses in female B6C3F1 mice. The present study was designed to evaluate whether or not these immunomodulatory responses were of sufficient magnitude to alter host resistances in a number of pathogen and tumor models. B6C3F1 mice were treated intraperitoneally with Thd (30-150 mg/kg) for 14 or 28 days, then inoculated with either Plasmodium yeolii, PYB6 fibrosarcoma tumor cells, B16F10 melanoma tumor cells, Listeria monocytogenes, or Streptococcus pneumoniae. Significant dose-dependent protection against B16F10 and L. monocytogenes was observed in mice that were treated with Thd. Furthermore, time course study using bacterial colony-forming units per spleen and liver as the endpoints indicated that the protective effect of Thd on host resistance to L. monocytogenes was time-dependent. In contrast, Thd treatment did not affect host resistance to P. yeolii, S. pneumoniae and PYB6 tumor. Additionally, the effect of Thd on the phagocytic function of the mononuclear phagocyte system (MPS) was evaluated following intravenous injection of 51Cr-labeled sRBCs. The overall phagocytic activity of MPS was not significantly altered by Thd treatment. In conclusion, these results demonstrate that Thd immunomodulation altered host resistance to B16F10 and L. monocytogenes; and selective modulation of Thd on the immune system may be responsible for the pathogen or tumor-specific effect of this compound.

Iron-mediated inhibition of H+-ATPase in plasma membrane vesicles isolated from wheat roots

The mechanisms of iron-mediated inhibition of the H(+)-ATPase activity of plasma membrane (PM) vesicles isolated from wheat roots were investigated. Both FeSO(4) and FeCl(3) significantly inhibited PM H(+)-ATPase activity, and the inhibition could be reversed by the addition of the metal ion chelator EDTA-Na(2) or a specific Fe(2+) chelator, indicating that the inhibitory effect was due to specific action of Fe(2+) or Fe(3+). Measurement of the extent of lipid peroxidation showed that oxidative damage on the PM caused by Fe(2+) or Fe(3+) seemed to be correlated with the inhibition of PM H(+)-ATPase activity. However, prevention of lipid peroxidation with butylated hydroxytoluene did not affect iron-mediated inhibition in the PM H(+)-ATPase, suggesting that the inhibition of the PM H(+)-ATPase was not a consequence of lipid peroxidation caused by iron. Investigation of the effects of various reactive oxygen species scavengers on the iron-mediated inhibition of H(+)-ATPase activity indicated that hydroxyl radicals (*OH) and hydrogen peroxide (H(2)O(2)) might be involved in the Fe(2+)-mediated decrease in PM H(+)-ATPase activity. Moreover, iron caused a decrease in plasma protein thiol (P-SH), and Fe(3+) brought a higher degree of oxidation in thiol groups than Fe(2+) at the same concentration. Modification of the thiol redox state in the PM suggested that reducing thiol groups were essential to maintain PM H(+)-ATPase activity. Incubation of the specific thiol modification reagent 5,5-dithio-bis(2-nitrobenzoic acid) with the rightside-out and inside-out PM revealed that thiol oxidation occurred at the apoplast side of the PM. Western blotting analysis revealed a decrease in H(+)-ATPase content caused by iron. Taken together, these results suggested that thiol oxidation might account for the inhibition of PM H(+)-ATPase caused by iron, and that *OH and H(2)O(2) were also involved in Fe(2+)-mediated inhibition.

Occupational and environmental risk factors for respiratory symptoms in rural Beijing, China

The aim of the present study was to determine the effects of occupational and environmental exposure on respiratory symptoms in adults in rural Beijing, China. Thirty randomly selected villages in the counties of Shunyi and Tongxian, 50 km north and east, respectively, of the city of Beijing, China, participated in this study. Village doctors interviewed all residents aged > or = 15 yrs and completed the International Union Against Tuberculosis and Lung Disease Questionnaire on Bronchial Symptoms translated into Chinese with added questions on smoking and occupational and environmental exposure. Of the eligible population, 22,528 adults (98%) took part. The prevalence of all respiratory symptoms, i.e. asthma-like symptoms, asthma attacks in the last 12 months, chronic cough and chronic phlegm, was low. Significant determinants for respiratory symptoms were age, sex, smoking and county of residence. A dose-dependent relationship was found between cumulative cigarette consumption and prevalence of respiratory symptoms. After adjusting for these variables, exposure to insecticides and fertilisers significantly increased the risk of most of the respiratory symptoms, whereas exposure to indoor air pollution from domestic fuels did not. Exposure to chemicals such as insecticides and fertilisers contributed independently to the risk of respiratory symptoms in rural Beijing, China.

Sodium metasilicate hypersensitivity in BALB/c mice

BACKGROUND

Sodium metasilicate (SMS) is a key ingredient for a number of industrial and consumer products. Although little is known about potential for this chemical to cause allergic reactions, a similar silicate compound, sodium silicate, was reported to elicit IgE-mediated contact urticaria.

OBJECTIVE

The aim of this study was to evaluate the potential for sodium metasilicate to elicit an allergic response in female BALB/c mice after dermal exposure.

METHODS

The primary irritancy assay (IA), local lymph node assay (LLNA), and a mouse ear swelling test (MEST) were used to evaluate the hypersensitivity response elicited by SMS exposure. An evaluation of lymph node subpopulations, cytokine mRNA expression, and serum IgE levels was also conducted.

RESULTS

SMS caused significant dermal irritation at concentrations >or=6% and an allergic response after mice were sensitized with 4% SMS then challenged with 6% SMS in the MEST. Lymph node cell proliferation was not observed in the LLNA after treatment with SMS (2% to 6% SMS). Increases in lymph node cellularity, the percentage of B cells, and the expression of certain cytokine mRNAs were observed in mice treated with SMS. Changes in the concentration of serum IgE after SMS treatment, however, were not observed.

CONCLUSIONS

SMS appears to elicit a chemical hypersensitivity response in mice, as indicated by the MEST, but not by the LLNA. Increases in auricular lymph node cellularity, the percentage of B cells, and certain cytokine mRNAs support classifying SMS as a weak chemical allergen.

Tuberculosis control priorities defined by using cost-effectiveness and burden of disease

OBJECTIVE

To define TB control priorities using cost-effectiveness and burden of disease.

METHODS

An assumed cohort of 2,000 cases was set up based on age-specific incidence of 794 newly registered smear-positive cases in Beijing in 1994. Prognostic trees and model diagrams of infectivity with natural history and DOTS intervention were constructed based on the epidemiological parameters.

RESULTS

DOTS reduced 89.19% of YLL, 78.90% of YLD, and 99.98% of infectivity BOD. One DALY could be saved with 45.70 Yuan by DOTS with 3% discount. Sensitivity analysis showed that discount had effect on CER. Weight of age was insensitive to CER. The higher the DOTS cured rate, the more the cost-effectiveness.

CONCLUSIONS

DOTS is a good cost-effectiveness TB control strategy. Cost-effectiveness and burden of disease can be used to define TB control priorities.

Methodology for the assessment of burden of smear-positive pulmonary TB and its infectivity

OBJECTIVE

The study investigated the burden of smear-positive pulmonary TB and its infectivity using DALY (disability-adjusted life year) as an indicator.

METHODS

An assumed cohort of 2,000 cases was set up based on the age-specific incidence of 794 newly registered smear-positive cases in Beijing in 1994. Prognostic trees and model diagrams of infectivity under natural history and DOTS(directly observed treatment, short-course) strategy were established according to the epidemiological evidence.

RESULTS

The results showed that 29.6% of DALYs would be neglected if the burden caused by the infectivity was not considered.

CONCLUSION

DOTS strategy may reduce 97.3% of the number of potential cases infected, 92.9% of DALYs related to TB-patients themselves, and 99.9% of DALYs caused by TB's infectivity as well.

Genistein modulates immune responses and increases host resistance to B16F10 tumor in adult female B6C3F1 mice

The isoflavone genistein (4,7,4'-trihydroxyisoflavone) is a phytoestrogen found in high levels in soy products that has been associated with decreased incidences of breast and prostate cancers. The potential effects of genistein on the immune system were evaluated in adult female B6C3F1 mice. Groups of mice were exposed to vehicle or genistein by gavage for 28 d. The doses of genistein used were 2, 6 and 20 mg/kg body. Consistent with the chemopreventive effect of genistein, exposure to this compound significantly increased host resistance to B16F10 tumor as reflected by a decrease in the number of lung tumor nodules after tumor cell injection at the middle and high dose levels. Inhibition of B16F10 tumor formation was not due to a direct effect of serum genistein and/or its metabolites on the proliferation of B16F10 tumor cells. When innate and acquired immune responses were evaluated, a dose-related increase of cytotoxic T-cell activity was observed in genistein-treated mice with significant changes observed at the middle and high dose levels. Furthermore, in vitro interleukin (IL)-2-stimulated natural killer (NK) cell activity was significantly enhanced in the high genistein dose group, although the basal NK cell activity was not affected. Although no affect on the mixed lymphocyte responses and anti-CD3 antibody-mediated splenocyte proliferation was observed, exposure to genistein significantly increased basal splenocyte proliferation. Exposure to genistein did not alter the activity of the mononuclear phagocyte system and the cytotoxic/cytostatic function of thioglycollate-recruited peritoneal cells on B16F10 tumor cells. Finally, exposure to genistein did not produce biologically meaningful changes in spleen immunoglobulin (Ig)M and IgG antibody-forming cell responses. In conclusion, genistein enhanced host resistance as evaluated in the B16F10 tumor model, which may be related to the increases in the activities of cytotoxic T cells and NK cells.

[Effect of subcutaneous tissue trimming on the survival skin area of avulsion skin flap]

OBJECTIVE

To investigate the effect of subcutaneous tissue trimming on the survival skin area of avulsion skin flap.

METHODS

Degloving injury was created in bilateral hind limbs of 7 pigs with avulsion injury machine, 4 cm x 10 cm avulsion skin flaps were elevated in degloving areas. Skin flaps in one side were replanted as control without any treatment. Subcutaneous tissue in the skin flaps of another side was partially excised and replanted by trimmed skin flaps. Survival skin flaps was calculated with computer at 7 days after operation.

RESULTS

In the control group, the survival skin area was (40.41 +/- 9.23)%, while in the experimental group, the survival skin area was (60.90 +/- 15.26)%. There was significant difference between the two groups (P < 0.05).

CONCLUSION

Trimming off subcutaneous tissue does improve the survival area of avulsion skin flap.

[Study on transplantation of anterolateral femoral skin flap with high site direct cutaneous artery]

OBJECTIVE

To study the availability of transplantation of anterolateral femoral skin flap with absence of the first branch of musculocutaneous artery.

METHODS

One hundred and sixty cases of anterolateral femoral skin flap transplantation in the past 15 years were reviewed, to investigate the relationship between the outcome of the transplantation and the types, distribution, original point, diameter of blood vessels. Among the 160 cases, there were 10 cases, 6.3% in total, of skin flap transplantation with the pedicle of high site direct cutaneous femoral artery, ranging from 10 cm x 14 cm to 12 cm x 18 cm in size, applied to repair soft tissue defect.

RESULTS

There were 149 cases, among the 160 cases, survived and all the 10 cases of femoral skin flap transplantation with high site anterolateral cutaneous artery survived.

CONCLUSION

The femoral skin flap with high site anterolateral cutaneous artery has good blood supply, larger size available, and easier operation. When the first branch of descending anterolateral femoral artery is absent, the femoral skin flap with high site anterolateral cutaneous artery is an optimal alternative.

The tuberculosis pandemic today: routes of transmission and new target groups

Tuberculosis, a disease that has been with us since the dawn of time, shows little sign of disappearing. Declines in death rates observed for several centuries prior to 1960 have been reversed in recent decades. This is in spite of the fact that efficient means of controlling the disease have been available during this period. This article reviews experience in 3 communities: among the Inuit, who live in the region of the North Pole; in the Beijing Municipality in the People's Republic of China; and in a socially isolated community in South Africa. In the first 2 communities, dramatic declines in the burden of disease have been observed: in the Inuit community, this occurred after substantial intervention; in the Beijing Municipality it was done with limited resources. The third community in South Africa illustrates an alarming trend, with tuberculosis being seen in a variety of locations but in the absence of external agents such as HIV infection. Clearly we need to refocus our efforts to control this disease, making use of the new tools that are rapidly becoming available. This must be done without delay, before influences such as HIV infection put the possibility of control completely out of reach.

Dermal exposure to cinnamaldehyde alters lymphocyte subpopulations, number of interferon-gamma-producing cells, and expression of B7 costimulatory molecules and cytokine messenger RNAs in auricular lymph nodes of B6C3F1 mice

BACKGROUND

Although the Murine Local Lymph Node Assay (LLNA) is efficient in identifying chemicals with sensitizing potential, there is increasing need for alternative end points. Cinnamaldehyde (CIN) was chosen for evaluation based on its moderate potency and extensive use in fragrance materials.

OBJECTIVES

The purpose of the present studies is to incorporate some alternative end points, such as phenotypic analysis and cytokine production, into a modified LLNA/irritancy assay (IA) to evaluate the sensitization of female B6C3F1 mice to CIN.

METHODS

Several nontraditional end points, including the analysis of lymphocyte subpopulations, B7 costimulatory molecule and cytokine messenger RNA (mRNA) expression, and intracellular interferon-gamma (IFN-gamma) levels, were incorporated into a modified murine local lymph node (LLNA)/irritancy assay (IA) to evaluate the sensitization of female B6C3F1 mice to cinnamaldehyde (CIN).

RESULTS

The alternate end points used in these studies support the classification of CIN as a moderately potent sensitizer. Dermal treatment with CIN resulted in an increase in the percentage of B cells in the auricular lymph nodes (ALNs) and expression of the costimulatory molecule, B7-2, on B cells. Lymph node cells also showed increased transforming growth factor-beta1, migration-inhibition factor, and mild increases in IFN-gamma and interleukin-2 cytokine mRNA expression. Although the increase in IFN-gamma mRNA expression did not translate into increased intracellular IFN-gamma levels, the absolute number of T cells producing IFN-gamma in the ALNs increased. Conversely, the MEST did not classify CIN as a contact allergen.

CONCLUSION

The nontraditional end points used in the LLNA/IA were not as sensitive as the traditional radioisotope method used to assess cell proliferation. However, they may help identify compounds inappropriately classified as sensitizers or nonsensitizers by the LLNA and MEST.

[Study on diagnosis and treatment of infections multiple organ dysfunction syndrome by integrated traditional Chinese and Western medicine]

OBJECTIVE

To explore the diagnostic and therapeutic approach of integrated traditional Chinese and western medicine (TCM-WM) on infectious multiple organ dysfunction syndrome/multiple system and organ failure (MODS/MSOF) for elevating the successful rate of rescuing the patients.

METHODS

Diagnosis with western medicine and Syndrome Differentiation of TCM in 225 in-patients of acute infectious disease complicated with MODS/MSOF were conducted, and TCM treatment, based on western medical comprehensive treatment, was given to observe the effect and explore the mechanism of the TCM-WM therapy.

RESULTS

Up to the end of 1998, 161 cases of the 225 cases were successfully cured and 64 died, the mortality being 28.4%. Among them, 58 out of 140 cases of MSOF died, the mortality was accounted for 41.4%. In 106 cases conformed to the diagnostic criteria of MSOF proposed by Professor Knaus WA, USA, 52 cases were cured successfully and 54 died, the mortality being 50.9%.

CONCLUSION

TCM-WM treatment could elevate the therapeutic effect in treating MODS, the mechanism might be through improving the hemodynamic and hemorrheologic condition of patients to relieve nail-fold microcirculation disorder; influencing the levels of cytokine and inflammatory mediator, so as to alleviate the systemic inflammatory reaction, it might also abate the inhibited condition of gastro-intestinal motility, alleviate the intestinal flora imbalance, prevent intestinal bacteria and endotoxin malposition, and protect cells from peroxidation.

Cost effectiveness of DOTS and non-DOTS strategies for smear-positive pulmonary tuberculosis in Beijing

The cost-effectiveness of DOTS (Directly Observed Treatment, short course) and non-DOTS strategies for smear-positive pulmonary tuberculosis in Beijing was evaluated. Cost calculation was based on the expenses of drugs, chest X-ray films, sputum smears and cultures for the patients. Effectiveness of the intervention was assessed in two aspects: direct benefits to the patients treated and indirect benefits to the others through reduced transmission of tuberculosis; disability adjusted life of year (DALY) was used as an index. The results showed that one DALY could be saved with 45.7 Yuan by DOTS and 471.4 Yuan by non-DOTS. DOTS is a good control strategy for smear-positive tuberculosis.

Cloning, expression and characterization of a cDNA (6A8) encoding a novel human alpha-mannosidase

A 3300-bp cDNA (6A8) has been isolated from a human tonsil cell lambdagt11 cDNA library (GenBank accession number: AF044414). The 6A8 gene is localized on human chromosome 13q31-32. Its cDNA has an open reading frame from position 57 bp to 3243 bp, encoding a 1062 amino-acid polypeptide. The sequence of the polypeptide has 89% identity to rat liver ER alpha-mannosidase. Homogenates of COS-7 cells transfected with 6A8 cDNA showed an enhanced enzymatic activity with p-nitro-phenyl-alpha-D-mannopyranoside, which was not inhibited by swainsonine. These data suggest that 6A8 alpha-mannosidase belongs to the class II alpha-mannosidase. Western blot analysis showed a band for 6A8 cDNA encoded protein of approximately 120 kDa. Northern blot analysis revealed two 6A8 mRNA transcripts with different tissue distribution. Enhanced concanavalin A (ConA) binding to CNE-2L2 cells transfected with a reverse 6A8 DNA was observed, indicating that the 6A8 protein is an important cellular alpha-mannosidase.

The impact of directly-observed treatment on the epidemiology of tuberculosis in Beijing

SETTING

Fully supervised chemotherapy, or directly observed treatment (DOT), for newly detected smear-positive cases in Beijing, has been successfully implemented for two decades.

OBJECTIVE

To evaluate the progress made in tuberculosis control, and in particular to evaluate the impact of DOT on tuberculosis epidemiology in Beijing.

DESIGN

Epidemiological parameters on tuberculosis, consisting of mortality, prevalence, notification rate, tuberculous meningitis in children and initial drug resistance rate, were collected and analysed. Their trends were evaluated and compared with DOT implemented for new smear-positive cases in Beijing from 1978 to 1996.

RESULTS

The coverage of DOT for new smear-positive pulmonary tuberculosis cases has increased from 10% in 1978 to more than 90% since 1990. Since DOT was introduced in 1978, mortality from tuberculosis has declined by an average of more than 7% per year. The reduction rate of 17.2%, and the rates of chronic cases and tuberculous meningitis in children decreased dramatically. The rate of newly registered smear-positive cases decreased from 18.9/100000 in 1986 to 7.3/100000 in 1996, giving an average annual reduction rate of 9.1 during this period. Initial resistance to isoniazid and streptomycin decreased from respectively 13.9% and 12.3% in 1978-1979 to 4.2% and 5.8% by 1996. The level of multidrug resistance was low and stable, at 0.8% in 1996.

CONCLUSION

The experience of the Beijing tuberculosis control programme convincingly demonstrates that it is possible to improve the epidemiological situation rapidly in a low-income country, at very low cost and in a manner that is self-sufficient and sustainable.

Risk of tuberculosis infection and tuberculous meningitis after discontinuation of Bacillus Calmette-Guerin in Beijing

In Beijing, the notification rate of smear-positive tuberculosis (TB) has been below 20 per 100,000 since 1986, and continues to decline. To accurately measure the risk of TB infection in a population in which the results of tuberculin skin testing were not confounded by vaccination with Bacillus Calmette-Guerin (BCG), BCG vaccination at birth was discontinued from 1988 in Shun-yi County. In 1995, the prevalence of TB infection among 12,836 primary school children aged 6 to 7 yr and without BCG scars was 1.4%, giving an estimated annual risk of infection of 0.19% (95% confidence interval: 0.16 to 0.22%). The prevalence of TB infection in children aged 5 to 9 yr in Beijing in 1950 was 46%. The number of cases of tuberculous meningitis did not increase after discontinuation of BCG. We conclude that discontinuation of BCG had no detectable harmful effects, and that control of TB in Beijing has markedly reduced the prevalence of TB infection since 1950.

Behavior of lanthanides in countercurrent chromatography using dihexyl-N,N-diethylcarbamoyl methylene phosphonate as stationary phase

Counter-current chromatography is a real liquid-liquid chromatography. The retention volume of the solute can be calculated from the batch distribution ratio in organic separations. In the separations of metal ion, there are several complex and dissociation reactions involved in the two phases, and the retention volume cannot be always predicted from the batch distribution ratio. A mass transfer model is proposed in this paper and an expression of V(R) is derived. The retention volume of metal ion is determined not only by the batch distribution ratio but also by the mechanism of the extraction reaction. When 25% dihexyl-N,N-diethylcarbamoyl methylenephosphonate in cyclohexane is used as stationary phase and 2.91 mol/l HNO3 as mobile phase, the dynamic distribution ratios obtained from the chromatogram are not equal to but proportional to the batch distribution coefficients. These results are in agreement with the theoretical expression.

Estimation of burden of disease for smear-positive pulmonary TB and its infectivity

The study investigated the burden of smear-positive pulmonary TB and its infectivity, using DALY (Disability-Adjusted Life Year) as an indicator. An assumed cohort of 2000 cases was set up based on the age-specific incidence of 794 newly registered smear positive cases of TB in Beijing in 1994. Prognostic trees and model diagrams of infectivity under natural history and DOTS (Direct Observed Treatment, Short-course) strategy were established according to the epidemiological evidence. The results show that 29.6% of DALYs would be neglected if the burden caused by the infectivity was not considered. The results also show that DOTS strategy may reduce 97.3% of the number of potential cases infected, 92.9% of DALYs related to TB-patients themselves, and 99.9% of DALYs caused by TB's infectivity as well.

Molecular cloning of human Hic-5, a potential regulator involved in signal transduction and cellular senescence

By using differential display, we cloned the human counterpart of the murine gene Hic-5 from senescent human keratinocytes. The full-length cDNA contained a short GC-stretch proceeding a consensus Kozak sequence followed by a single open reading frame of 1338 bp encoding a 461-amino acid protein with a predicted molecular weight of 50 kDa. The expression of this gene was prominent in cells of epithelial origin but low or absent in lymphoid tissues and hematopoietic cells. The deduced protein contained four LIM domains at the carboxyl-terminal end and four LD motifs at the amino-terminal half, sharing high similarities with the focal adhesion protein paxillin. Hic-5 may therefore function, like paxillin, as a potential adapter for the recruitment of structural and signaling molecules to certain subcellular sites or in focal adhesions. Isolation of the genomic sequence revealed that the gene covered a segment of 6 kb and spanned 11 exons from the translation initiation site ATG to the termination signal TGA. Fluorescent in situ hybridization by using a human Hic-5 specific probe localized the gene to human chromosome 16p11.

[Antagonistic effects of melatonin on glutamate-induced neurotoxicity in rat hippocampal neurons]

The effects of glutamate (Glu) and melatonin (MEL) on the evoked populaion spike (PS) following stimulation of the schaffer collateral fiber were studied by extracellular recording technique in perfused slices of rat hippocampus: 5.0 mmol/L Glu decreased the PS peak values to 4.1% of control. This effect of Glu (5.0 mmol/L) on PS peak values was changed to 14.7%, 105.2% and 24.3% of control by 0.4, 0.5, 0.6 mumol/L of MEL. But when the interaction between MEL (0.5 mumol/L) and Glu (5.0 mmol/L) was entirely suppressed by CDP (0.5 mumol/L), the PS values reduced to zero. These results suggest that the inhibitory action of MEL on Glu-induced neurotoxicity may be mediated by 5-HT receptors.

Neural plasticity and emotional memory

Posttraumatic stress disorder is the pathological replay of emotional memory formed in response to painful, life-threatening, or horrifying events. In contrast, depression is often precipitated by more social context-related stressors. New data suggest that different types of life experiences can differentially impact biochemistry, physiology, anatomy, and behavior at the level of changes in gene expression. Repeated separation of neonatal rat pups from their mother results in many long-lasting alterations in biology and behavior paralleling that in depression, including hypercortisolism. The role of the amygdala in modulating emotional memory is highlighted, as well as some of its unique properties such as metaplasticity (i.e., the differential direction of long-term adaptation, either potentiation or depression) in response to the same input as a function of the prior history of stimulation. The implications of these emerging data on the physiological and molecular mechanisms underlying emotional memory emphasize the particular importance of prevention and early intervention.

Apoptosis of hippocampal neurons after amygdala kindled seizures

Seizure-induced neuronal damage may involve both excitotoxic and apoptotic (programmed cell death) mechanisms. In the present study, we used an amygdala kindled seizure model to study whether apoptotic cell death occurs. To evaluate apoptosis, we counted the numbers of cells that had DNA fragments labeled at the 3' end with digoxigenin using terminal transferase (ApopTag, Oncor). Additionally, the expression of Bax and Bcl-2, two genes associated with apoptotic cell death, was also measured following kindled seizures. We found that the number of ApopTag-positive cells in the hippocampus increased 30.4% after one kindled seizure and 82.5% after 20 seizures compared to sham controls. The ApopTag-labeled cells could be mainly interneurons of the hippocampal formation, although additional studies are required. Preferential vulnerability of inhibitory interneurons is consistent with previous studies on seizure-induced cell loss. These results, coupled with our findings that the ratio of Bax/Bcl-2 expression is increased in the hippocampus by seizures, suggest that apoptosis of hippocampal interneurons may lead to dysinhibition in the hippocampus and increased seizure susceptibility.

In situ investigation of Fas/FasL expression in chronic hepatitis B infection and related liver diseases

To evaluate Fas/FasL expression in hepatitis B virus-related chronic liver disease, liver biopsies from 44 such cases were studied immunohistochemically. FasL was detected in the infiltrating lymphocytes and both FasL and Fas were found in the hepatocytes. The Fas and FasL-positive cells were mostly found at the advancing edges of interphase hepatitis, and Fas/FasL expression was closely correlated with the inflammatory activity. Unexpectedly, FasL was also expressed in liver cirrhotic nodules, particularly in those with hepatocellular carcinoma with or without inflammation. These results suggest that the factors which induce hepatocyte transformation might also trigger FasL expression and promote FasL/Fas-mediated apoptosis.