Waste rubber - Black pollution reframed as a global issue: Ecological challenges and sustainability initiatives.

In contrast to "white pollution" originating from waste plastics, waste rubber is often referred to as "black pollution." The quantity and variety of waste rubber are increasing at an alarming rate, with a considerable fraction entering the global ecosystem via various pathways. This study presents the first critical review of waste rubber research with a focus on the risks associated with toxicant discharge and existing problems in waste rubber disposal, management, and recycling practices. We aim to obtain a comprehensive understanding of current research, particularly regarding the ecological impacts of these wastes, highlight major gaps, and propose the most significant research directions. A total of 192 studies published in journals were critically analysed. The importance of conducting long-term and large-scale experiments and developing efficient waste rubber recycling systems is also emphasised. This study highlights the need to address the challenges posed by waste rubber pollution and offers insights and references for undertaking ecological risk assessments and understanding the mechanisms underlying toxicant behaviour. Suggestions and countermeasures are proposed with ecosystem sustainability as the ultimate goal. Further long-term, comprehensive, and systematic research in this area is required.

Competitive interactions and coexistence of sympatric flagship carnivores in Asia.

Understanding the competition and coexistence of flagship carnivores is key to creating strategies for their conservation in the face of global carnivore declines. Although studies exploring the dynamics and competition between tigers (Panthera tigris) and leopards (P. pardus) span decades, there is a lack of understanding regarding the factors that influence their coexistence mechanisms on a broad scale, as well as the drivers determining their exploitative and interference competition. We gathered a comprehensive list of research papers among which 36 papers explored the interspecific interactions between tigers and leopards and tested the influence of biotic and abiotic factors on the coexistence mechanisms along three dimensions using multiple response variables regression models; we also tested the influence of ecological drivers determining the exploitative or interference competition between tigers and leopards. Elevation and ungulate density were the most important predictors in regulating the coexistence mechanisms. Tigers and leopards exhibited more positive relations/higher overlaps as elevation increased in the spatial niche. In addition, they showed a higher dietary overlap in the prey-rich regions. We determined that interference competition between tigers and leopards was less frequently observed in habitats with dense tree cover and homogeneous vegetation structures. Meanwhile, studies with multiple metrics would promote the detection of interference competition. Our study provides new insight into the competitive interactions and coexistence mechanisms of tigers and leopards on a broad scale. Policy-makers and managers should pay more attention to the factors of elevation, prey abundance, and habitat structures for the conservation of tigers and leopards.

Assessing mammal population densities in response to urbanization using camera trap distance sampling.

Environmental filtering is deemed to play a predominant role in regulating the abundance and distribution of animals during the urbanization process. However, the current knowledge about the effects of urbanization on the population densities of terrestrial mammals is limited. In this study, we compared two invasive mammals (dogs Canis lupus familiaris and cats Felis silvestris) and three indigenous mammals (Siberian weasels Mustela sibirica, Amur hedgehogs Erinaceus amurensis, and Tolai hares Lepus tolai) in response to urbanization using camera trap distance sampling (CTDS) in the rural-urban landscape of Tianjin, China. We used generalized additive mixed models (GAMMs) to test the specific responses of their densities to levels of urbanization. Invasive dogs (2.63 individuals/km2, 95% CI: 0.91-7.62) exhibited similar density estimations to cats (2.15 individuals/km2, 95% CI: 1.31-3.50). Amur hedgehogs were the most abundant species (6.73 individuals/km2, 95% CI: 3.15-14.38), followed by Tolai hares (2.22 individuals/km2, 95% CI: 0.87-5.68) and Siberian weasels (2.15 individuals/km2, 95% CI: 1.06-4.36). The densities of cats, Siberian weasels, and Amur hedgehogs increased with the level of urbanization. The population densities of dogs and cats were only influenced by urban-related variables, while the densities of Siberian weasels and Amur hedgehogs were influenced by both urban-related variables and nature-related variables. Our findings highlight that the CTDS is a suitable and promising method for wildlife surveys in rural-urban landscapes, and urban wildlife management needs to consider the integrated repercussions of urban- and nature-related factors, especially the critical impacts of green space habitats at finer scales.

Multi-omics provide mechanistic insight into the Pb-induced changes in tadpole fitness-related traits and environmental water quality.

Water pollution from lead/Pb2+ poses a significant threat to aquatic ecosystems, and its repercussions on aquatic animals have received considerable attention. Although Pb2+ has been found to affect numerous aspects of animals, including individual fitness, metabolic status, and symbiotic microbiota, few studies have focused on the associations between Pb2+-induced variations in fitness, metabolome, symbiotic microbiome, and environmental parameters in the same system, limiting a comprehensive understanding of ecotoxicological mechanisms from a holistic perspective. Moreover, most ecotoxicological studies neglected the potential contributions of anions to the consequences generated by inorganic lead compounds. We investigated the effects of Pb(NO3)2 at environmentally relevant concentrations on the Rana omeimontis tadpoles and the water quality around them, using blank and NaNO3-treated groups as control. Results showed that Pb(NO3)2 not only induced a rise in water nitrite level, but exposure to this chemical also impaired tadpole fitness-related traits (e.g., growth and development). The impacts on tadpoles were most likely a combination of Pb2+ and NO3-. Tissue metabolomics revealed that Pb(NO3)2 exposure influenced animal substrate (i.e., carbohydrate, lipid, and amino acid) and prostaglandin metabolism. Pb(NO3)2 produced profound shifts in gut microbiota, with increased Proteobacteria impairing Firmicutes, resulting in higher aerobic and possibly pathogenic bacteria. NaNO3 also influenced tadpole metabolome and gut microbiome, in a manner different to that of Pb(NO3)2. The presence of NO3- seemed to counteract some changes caused by Pb2+, particularly on the microbiota. Piecewise structural equation model and correlation analyses demonstrated connections between tissue metabolome and gut microbiome, and the variations in tadpole phenotypic traits and water quality were linked to changes in tissue metabolome and gut microbiome. These findings emphasized the important roles of gut microbiome in mediating the effects of toxin on aquatic ecosystem. Moreover, it is suggested to consider the influences of anions in the risk assessment of heavy metal pollutions.

E. coli diversity: low in colorectal cancer.

BACKGROUND: Escherichia coli are mostly commensals but also contain pathogenic lineages. It is largely unclear whether the commensal E. coli as the potential origins of pathogenic lineages may consist of monophyletic or polyphyletic populations, elucidation of which is expected to lead to novel insights into the associations of E. coli diversity with human health and diseases. METHODS: Using genomic sequencing and pulsed field gel electrophoresis (PFGE) techniques, we analyzed E. coli from the intestinal microbiota of three groups of healthy individuals, including preschool children, university students, and seniors of a longevity village, as well as colorectal cancer (CRC) patients, to probe the commensal E. coli populations for their diversity. RESULTS: We delineated the 2280 fresh E. coli isolates from 185 subjects into distinct genome types (genotypes) by PFGE. The genomic diversity of the sampled E. coli populations was so high that a given subject may have multiple genotypes of E. coli, with the general diversity within a host going up from preschool children through university students to seniors. Compared to the healthy subjects, the CRC patients had the lowest diversity level among their E. coli isolates. Notably, E. coli isolates from CRC patients could suppress the growth of E. coli bacteria isolated from healthy controls under nutrient-limited culture conditions. CONCLUSIONS: The coexistence of multiple E. coli lineages in a host may help create and maintain a microbial environment that is beneficial to the host. As such, the low diversity of E. coli bacteria may be associated with unhealthy microenvironment in the intestine and hence facilitate the pathogenesis of diseases such as CRC.

Efficient Human Cytomegalovirus Replication in Primary Endothelial Cells Is SOCS3 Dependent.

BACKGROUND: In immunocompromised patients, human cytomegalovirus (HCMV) infection is a major cause of morbidity and mortality. Suppressor of cytokine signaling (SOCS) proteins are very potent negative regulators of the janus kinase/signal transducer and activator of transcription (JAK/STAT) pathways. We hypothesized that HCMV exploits SOCS1 and/or SOCS3 to its advantage. METHODS: All experiments were carried out with primary human lung-derived microvascular endothelial cells (HMVEC). SOCS1 and SOCS3 were silenced by transfecting the cells with siRNA. HCMV was propagated and titered on human lung-derived fibroblasts MRC5. Real-time PCR and Western blot were used to detect mRNA and protein levels, respectively. RESULTS: The data presented show that an efficient replication of HCMV in HMVEC is dependent on SOCS3 protein. Time course analysis revealed an increase in SOCS3 protein levels in infected cells. Silencing of SOCS3 (siSOCS3) resulted in inhibition of viral immediate early, early, and late antigen production. Consistently, HCMV titers produced by siSOCS3 cultures were significantly decreased when compared to control transfected cultures (siCNTRs). STAT1 and STAT2 phosphorylation was increased in siSOCS3-infected cells when compared to siCNTR-treated cells. CONCLUSION: These findings indicate the implication of SOCS3 in the mechanism of HCMV-mediated control of cellular immune responses.

A rapid loop-mediated isothermal amplification (LAMP) method for detection of the macrolide-streptogramin type B resistance gene msrA in Staphylococcus aureus.

Macrolide-streptogramin type B resistance (the MSB phenotype) is a multidrug resistance phenotype in Staphylococcus aureus conferred by the resistance gene msrA. However, bacteria having the MSB phenotype are susceptible to lincosamides and 16-membered ring macrolides, which makes profiling resistance genes necessary and urgent for timely and appropriate use of antimicrobials. In this study, the loop-mediated isothermal amplification (LAMP) assay was optimized for prompt detection of the msrA gene. msrA gene sequences were obtained from the National Center for Biotechnology Information (NCBI) database and primers were designed using the LAMP primer designing software PrimerExplorer v.4, which together recognize seven distinct regions of the msrA gene. The specific LAMP primer set designed in this study could amplify the msrA gene within 25min at an isothermal temperature of 62°C. More importantly, the msrA gene could be detected at a sensitivity as low as 100pg. Furthermore, this optimized LAMP assay provided swift detection of the msrA gene even directly from human specimens. In conclusion, this assay may have great clinical application potential for detection of the msrA gene.

Transient partial response of poorly-differentiated thyroid carcinoma to sunitinib treatment: A case report.

Thyroid cancer is the most common endocrine malignancy, with an increasing prevalence worldwide. Poorly-differentiated thyroid cancer (PDTC) is relatively rare and its prognosis is poor. To date, no ideal treatment strategy is available for patients with advanced recurrent PDTC, particularly for patients in crisis. However, partial success in treating thyroid cancer has been achieved with targeted therapy, and advances made in understanding the molecular biology of the tumor. The current study describes the case of a patient diagnosed with PDTC following presentation with hoarseness, orthopnea, and a large right neck mass. A transient partial response to sunitinib malate treatment was achieved for >3 months. In addition, the current study reviewed the relevant literature and discussed the therapeutic value of sunitinib as a more favorable treatment strategy for patients with advanced recurrent PDTC compared with the currently available treatments. Successful treatment with sunitinib, as well as molecular analysis of the tumor, occurred in the present case. Sunitinib was determined to have potential in treating thyroid tumors, however, larger prospective studies are required to validate the findings of the current case study prior to the application of this agent in clinical practice.

DHA-1 plasmid-mediated AmpC ß-lactamase expression and regulation of Klebsiella pnuemoniae isolates.

The present study aimed to investigate the regulatory mechanism of the AmpC enzyme by analyzing the construction and function of AmpCR, AmpE and AmpG genes in the Dhahran (DHA)­1 plasmid of Klebsiella pneumoniae (K. pneumoniae). The production of AmpC and extended­spectrum ß­lactamase (ESBL) were determined following the cefoxitin (FOX) inducing test for AmpC, preliminary screening and confirmation tests for ESBL in 10 DHA­1 plasmid AmpC enzymes of K. pneumoniae strains. AmpCR, AmpD, AmpE and AmpG sequences were analyzed by polymerase chain reaction. The pACYC184­X plasmid analysis system was established and examined by regulating the pAmpC enzyme expression. The electrophoretic bands of AmpCR, AmpD, AmpE and AmpG were expressed. Numerous mutations in AmpC + AmpR (AmpCR) and in the intergenic region cistron of AmpC­AmpR, AmpD, AmpE and AmpG were observed. The homology of AmpC and AmpR, in relation to the Morganella morganii strain, was 99%, which was determined by comparing the gene sequences of Kp1 with those of Kp17 AmpCR. The specific combination of AmpR and labeled probe demonstrated a band retarded phenomenon and established a spatial model of AmpR. All the enzyme production strains demonstrated Val93→Ala in AmpG; six transmembrane domains were found in AmpE in all strains, with the exception of Kp1 and Kp4, which had only three transmembrane segments that were caused by mutation. The DHA­1 plasmid AmpC enzymes encoded by plasmid are similar to the inducible chromosomal AmpC enzymes, which are also regulated by AmpD, AmpE, AmpR and AmpG.

Triggering TLR2, -3, -4, -5, and -8 reinforces the restrictive nature of M1- and M2-polarized macrophages to HIV.

UNLABELLED: Macrophages must react to a large number of pathogens and their effects. In chronic HIV infection, the microenvironment changes with an influx of microbial products that trigger Toll-like receptors (TLRs). That dynamic nature can be replicated ex vivo by the proinflammatory (M1-polarized) and alternatively activated (M2-polarized) macrophages. Thus, we determined how polarized macrophages primed by various TLR agonists support HIV replication. Triggering of TLR2, -3, -4, -5, and -8 reinforced the low level of permissiveness in polarized macrophages. HIV was inhibited even more in M1-polarized macrophages than in macrophages activated only by TLR agonists. HIV was inhibited before its integration into the host chromosome. Polarization and triggering by various TLR agonists resulted in distinct cytokine profiles, endocytic activity, and distinct upregulation of restriction factors of HIV. Thus, different mechanisms likely contribute to the HIV-inhibitory effects. In chronic HIV infection, macrophages might become less permissive to HIV due to changes in the microenvironment. The high level of reactivity of polarized macrophages to TLR triggering may be exploited for immunotherapeutic strategies. IMPORTANCE: Macrophages are a major target of HIV-1 infection. Different cell types in this very heterogeneous cell population respond differently to stimuli. In vitro, the heterogeneity is mimicked by their polarization into proinflammatory and alternatively activated macrophages. Here we explored the extent to which agonists triggering the TLR family affect HIV replication in polarized macrophages. We found that a number of TLR agonists blocked HIV replication substantially when given before infection. We also report the mechanisms of how TLR agonists exert their inhibitory action. Our findings may advance our understanding of which and how TLR agonists block HIV infection in polarized macrophages and may facilitate the design of novel immunotherapeutic approaches.

Pseudomonas aeruginosa isolates of distinct sub-genotypes exhibit similar potential of antimicrobial resistance by drugs exposure.

Pseudomonas aeruginosa, a wide-spread opportunistic pathogen, often complicates clinical treatments due to its resistance to a large variety of antimicrobials, especially in immune compromised patients, occasionally leading to death. However, the resistance to antimicrobials varies greatly among the P. aeruginosa isolates, which raises a question on whether some sub-lineages of P. aeruginosa might have greater potential to develop antimicrobial resistance than others. To explore this question, we divided 160 P. aeruginosa isolates collected from cities of USA and China into distinct genotypes using I-CeuI, a special endonuclease that had previously been proven to reveal phylogenetic relationships among bacteria reliably due to the highly conserved 26-bp recognition sequence. We resolved 10 genotypes by I-CeuI analysis and further divided them into 82 sub-genotypes by endonuclease cleavage with SpeI. Eight of the 10 genotypes contained both multi-drug resistant (MDR) and less resistant isolates based on comparisons of their antimicrobial resistance profiles (ARPs). When the less resistant or susceptible isolates from different genotypes were exposed to eight individual antimicrobials, they showed similar potential to become resistant with minor exceptions. This is to our knowledge the first report to examine correlations between phylogenetic sub-lineages of P. aeruginosa and their potential to become resistant to antimicrobials. This study further alerts the importance and urgency of antimicrobial abuse control.

[Histological changes after the recontruction of tongue defect with rectus abdominis musculoperitoneal flap].

OBJECTIVE: To observe the cellular morphological and histological changes of the reconstructed tongue defect by rectus abdominis musculoperitoneal flap of dogs with or without nerve. METHODS: 12 Beagle dogs were randomly divided into two groups. Group A made rectus abdominis musculoperitoneal flap with the intercostal nerve while group B without the intercostal nerve. Nerve anastomosis was performed in Group A while not in Group B in the repairment. 12 weeks later, the length, width, surface area and cellular morphology and histological changes of the two transfer flaps were observed. RESULTS: The length, width, surface area of transplanted rectus abdominis musculoperitoneal flaps in group A were greater than those in Group B, and the differences were statistically significant at 12th week (P < 0.01). The microscope study found that the transplanted rectus abdominis musculoperitoneal flaps of group A had part of muscle fiber atrophy with some connective and adipose tissue, loose muscle fiber arrangement, while the transplanted rectus abdominis musculoperitoneal flaps of Group B had muscle cells atrophy with some adipocyte. The structure of muscle cells in Group A was basically normal, but it was disorder in Group B. The type II muscle fibers of Group B was atrophy and substituted by a lot of connective tissue. CONCLUSION: After tongue defect reconstructed by rectus abdominis musculoperitoneal flap with nerve, the changes of muscle fibers could be similar to tongue muscles, providing a basis for the dynamic recovery of the tongue.

Identification of genotypes of plasmid-encoded AmpC beta-lactamases from clinical isolates and characterization of mutations in their promoter and attenuator regions.

We investigated the occurrence of AmpC beta-lactamases among Escherichia coli and Klebsiella pneumoniae isolates and determined the genotype of plasmid-mediated AmpC beta-lactamases at a medical center. The AmpC beta-lactamase promoter and attenuator were amplified from chromosomal DNA of high AmpC-producing E. coli isolates and sequenced. Antibiotic screening and 3D extract tests showed the presence of AmpC beta-lactamase in 3.56% of K. pneumoniae and 1.88% of E. coli isolates. Ten isolates (six K. pneumoniae and four E. coli) were positive for extended spectrum beta-lactamase (ESBL) as indicated by the double disc diffusion method. DHA-1 plasmid-encoded AmpC beta-lactamase was present in 10 K. pneumoniae isolates and four E.coli isolates. E. coli chromosomal AmpC beta-lactamase carried polymorphisms in the -42, -32, and -18 bases of the promoter and in the +26 and +27 bases of the attenuator, which may play a role in antibiotic resistance. The observed mutations may have clinical implications for the management of antibiotic-resistant infections.

[GenoType MTBDRplus assay for rapid detection of rifampin and isoniazid resistance in Mycobacterium tuberculosis in Sichuan].

OBJECTIVE: To explore the molecular and epidemic characteristics of rifampin (RFP) and isoniazid (INH) resistance of mycobacterium tuberculosis (MTB) in Sichuan. METHODS: GenoType reg; MTBDRplus Assay GTplus was used to examine 68 clinical isolates of MTB and 105 clinical specimens for mutations in rpoB, katG and inhA genes related to RFP and INH resistance. RESULTS: Of the 151 valid tests obtained, 44 (29.14%) and 26 (17.22%) showed drug resistance and multidrug resistance, respectively. Resistance to RFP and INH was found in 21.85% (33/151) and 24.50% (37/151) of the samples, respectively. The most prevalent mutations were rpoB S531L, katG S315T1 and inhA C-15T. The multidrug resistance rate in the sputum specimens was significantly higher than that in the non-respiratory samples (19.35% vs 7.41%). CONCLUSION: Drug-resistant, especially multidrug-resistant tuberculosis is highly prevalent in Sichuan. The multidrug-resistant bacteria most frequently show rpoB S531L combined with katG S315T1 mutations, suggesting the necessity of developing rapid clinical identification methods for drug-resistant MTB to control the spread of the resistant strains.

[Changes of high-sensitivity CRP and insulin sensitivity index in children with obstructive sleep apnea hypopnea syndrome].

OBJECTIVE: To investigate the levels of high-sensitivity CRP (hsCRP) and insulin sensitivity index (ISI) in children with obstructive sleep apnea hypopnea syndrome (OSAHS). METHODS: Twenty-nine children with OSAHS and 22 children with primary snoring (PS) were enrolled. Polysomnography was performed. Body mass index (BMI), hsCRP, serum lipids, fasting plasma glucose (FPG), and insulin (INS) were measured. ISI was calculated. RESULTS: The apnea hypopnea index (AHI) in the OSAHS group was higher than that in the PS group (13.2 ± 9.2 vs 1.2 ± 1.1; P<0.05). The lowest oxygen saturation (LSaO2) in the OSAHS group was lower than that in the PS group [(78.5 ± 5.4)% vs (87.4 ± 3.7)%; P<0.05]. The values of hsCRP in the OSAHS group was higher than those in the PS group (2.8 ± 2.7 mg/L vs 0.6 ± 0.9 mg/L; P<0.05). There were no significant differences in the ISI and serum lipids between the two groups. The hsCRP level was negatively correlated with LSaO2 in the OSAHS group (r=-0.531, P<0.05). CONCLUSIONS: The hsCRP level increases in children with OSAHS. The increased hsCRP level might be associated with an increased risk of cardiovascular diseases.

[Study of plasma temperature measurements for oxygen discharge].

A radio-frequency discharge setup was constructed by two shell-shaped copper electrodes and a 30 cm long pyrex glass tube (i. d. = 1.65 cm) to examine the gas temperature of oxygen plasma in electric discharge oxygen iodine laser. The discharge was supplied by a 500 watt, 13.56 MHz radio-frequency power. The gas pressure in the discharge cavity was 1 330 Pa. The temperature of oxygen discharge plasma was measured by using the P branch of O2 (b, v = 0) rotational emission spectrum. Two methods were used to deduce the oxygen gas temperature. They are Boltzman plotting method and computer simulating spectrum method, respectively. Gauss fitting method was used to distinguish spectrum peaks for lower resolution spectrum. The spectrum peak area was used to characterize the optical emission intensity. The gas temperature of oxygen discharge plasma was obtained by Boltzmann plotting method. Alternatively, the optical emission spectrum was simulated by computer modeling with spectrometer slit function which was obtained by He-Ne laser. Consequently, the gas temperature of oxygen plasma was obtained by comparing the computer simulating spectrum and the experimentally observed spectrum according to the least square fitting rule. The measurement results with the two methods agree well. It was concluded that the simple optical technique can be used conveniently in the temperature diagnostics of oxygen radio-frequency discharge plasma.

[Prevalence of upper respiratory tract group A Streptococcus carriage in school-age children from Tulufan City and Buerjin County of Xinjiang Province].

OBJECTIVE: To study the prevalence rate of upper respiratory tract group A Streptococcus (GAS) carriage in school-age children from Xinjiang Province. METHODS: A total of 478 children at age of 9-12 years from Tulufan City and Buerjin County of Xinjiang Province were enrolled by random cluster sampling. Throat swab cultures were performed once each season for the determination of presence of GAS. RESULTS: In the 1 827 samples, 196 GAS strains were isolated, with a GAS carrier rate of 10.7%. The prevalence rate of GAS carrier in Tulufan City ranged from 3.7%-16.5% compared with 4.7%-21.4% in Buerjin County (P < 0.05). The prevalence rate of GAS carrier in winter is the highest, followed by in autumn, spring and summer in both regions. There were significant differences in the GAS carriage rate in autumn between the two regions. There were no significant differences in the GAS carriage rate between boys and girls. Of the 196 GAS strains, 133 from Han, 22 from Uygur and 41 from Hazakh children. There were significant differences in the prevalence rate of GAS carriage among children with different ethic groups. CONCLUSIONS: The prevalence rate of GAS carriage is high in school-age children from Tulufan and Buerjin of Xinjiang Province. The GAS carrier rate is associated with the season and ethic group. The children from Buerjin County present a higher GAS carrier rate than those from Tulufan City.

[Diagnostic values of serum orexin-A levels in children with obstructive sleep apnea-hypopnea syndrome].

OBJECTIVE: Currently people regard polysomnography (PSG) monitoring as the golden standard for diagnosis of obstructive sleep apnea-hypopnea syndrome (OSAHS) in children. However, due to the high cost, time and manpower consuming, PSG is not applicable to epidemiological investigation and clinical screening, especially not suitable for child patients and remote hospitals in Xinjiang. Therefore, it is of important clinical significance to find out a simple method (e.g. a kind of serum index) to primarily screen out suspicious patients for early diagnosis and treatment. The present study was conducted to assess the clinical usefulness of the measurement of orexin-A concentration in serum as a diagnostic predictor to screen patients with OSAHS in children. METHODS: Serum orexin-A concentration was measured with enzyme immunoassay (EIA) kit in 60 patient with snoring before performing polysomnography (PSG). Subsequently all the subjects underwent PSG test. Forty subjects were diagnosed as having OSAHS, and twenty subjects had no OSAHS. These 20 non-OSAHS subjects served as controls. Compared with the PSG results the clinical usefulness of the measurement of orexin-A concentration in serum was assessed as a diagnostic predictor to screen patients with OSAHS. Correlation between orexin-A levels and apnea hypoventilation index (AHI), micro-arousal index (MAI) and lowest SaO2 (LSaO2) were analyzed. RESULTS: The serum orexin-A levels in the OSAHS group [(0.49 +/- 0.10) microg/L] was significantly higher than that of the control group [(0.28 +/- 0.11) microg/L, P < 0.01]. If a patient's level of orexin-A was higher than 0.36 microg/L, the patient more likely to have OSAHS. The sensitivity rate was 85.0% and the specificity was 80.0%. Serum orexin-A levels in children with OSAHS correlated positively with the AHI (r = 0.427, P < 0.05) and MAI (r = 0.468, P < 0.05), but correlated negatively with the LSaO2 (r = -0.527, P < 0.01) and the mean oxygen saturation (MSaO2) (r = -0.541, P < 0.01), not correlated significantly with the BMI (r = -0.212, P > 0.05). The serum orexin-A levels in the OSAHS children after who under went tonsillectomy and adenoidectomy significantly decreased (P < 0.05) 3 months after surgery as compared with pre-operation level. CONCLUSION: These findings suggest that the serum level of orexin-A could be used as a predictor in screening for OSAHS children and a biological marker of the severity of OSAHS children.

[Protection of azithromycin against pulmonary II epithelial cell injuries induced by cigarette smoke extract and relevant mechanisms].

OBJECTIVE: Cigarette smoke extract (CSE) can induce injuries of pulmonary II epithelial cells, activate nuclear factor-kappaB and increase tumor necrosis factor-alpha(TNF-alpha) secretion. This study aimed to investigate whether azithromycin can protect pulmonary II epithelial cells from injuries induced by CSE and relevant mechanisms. METHODS: Pulmonary II epithelial cells (A549 cells) were cultured in vitro. After 48 hrs of culture the cells were randomly treated with serum-free DMEM only (blank control group), azithromycin + serum-free DMEM, CSE+ serum-free DMEM or CSE+azithromycin. Eight hours later the morphology of A549 cells, the activity of NF-kappaB and the levels of TNF-alpha were measured by inverted microscope, immunohistochemistry and ELISA. RESULTS: The morphology and structure of A549 cells were changed, NF-kappaB activity increased (dark brown staining ) and TNF-alpha levels (0.307 +/- 0.036 pg/mL vs 0.234 +/- 0.028 pg/mL)increased in the CSE+ serum-free DMEM group compared with the blank control group (P < 0.01). CSE together with azithromycin treatment recovered partly the morphological injuries of A549 cells. It also attenuated NF-kappaB staining and decreased TNF-alpha levels from 0.307 +/- 0.036 pg/mL (CSE+serum-free DMEM group) to 0.269 +/- 0.009 pg/mL (P < 0.05). CONCLUSIONS: Azithromycin may inhibit NF-kappaB activity, decrease TNF-alpha secretion and thus lessen cytotoxicity of CSE to A549 cells.