Low-level ambient ozone exposure associated with neutrophil extracellular traps and pro-atherothrombotic biomarkers in healthy adults

BACKGROUND AND AIMS

Uncertainty of the causality determinations for ambient ozone (O3) on cardiovascular events is heightened by the limited understanding of the mechanisms involved in humans. We aimed to examine the pro-atherothrombotic impacts of O3 exposure and to explore the potential mediating roles of dysfunctional neutrophils, focusing on neutrophil extracellular traps (NETs).

METHODS

A longitudinal panel study of 152 healthy adults was conducted in the cool to cold months with relatively low levels of O3 between September 2019 and January 2020 in Beijing, China. Four repeated measurements of indicators reflecting atherothrombotic balance and NETs were performed for each participant.

RESULTS

Daily average exposure levels of ambient O3 were 16.6 μg/m3 throughout the study period. Per interquartile range increase in average concentrations of O3 exposure at prior up to 7 days, we observed elevations of 200.1-276.3% in D-dimer, 27.2-36.8% in thrombin-antithrombin complex, 10.8-60.3% in plasminogen activator inhibitor 1, 13.9-21.8% in soluble P-selectin, 16.5-45.1% in matrix metalloproteinase-8, and 2.4-12.4% in lipoprotein-associated phospholipase A2. These pro-atherothrombotic changes were accompanied by endothelial activation, lung injury, and immune inflammation. O3 exposure was also positively associated with circulating NETs indicators, including citrullinated histone H3, neutrophil elastase, myeloperoxidase, and double-stranded DNA. Mediation analyses indicated that NETs could mediate O3-associated pro-atherothrombotic responses. The observational associations remained significant and robust after controlling for other pollutants, and were generally greater in participants with low levels of physical activity.

CONCLUSIONS

Ambient O3 exposure was associated with significant increases in NETs and pro-atherothrombotic potential, even at exposure levels well below current air quality guidelines of the World Health Organization.

[Resistance to deltamethrin and its association with mutation sites in the sodium iron channel domain III gene in Rhipicephalus microplus in Huaihua City of Hunan Province]

OBJECTIVE

To investigate the level of deltamethrin resistance and mutation sites in the sodium iron channel gene in Rhipicephalus microplus in Huaihua City, Hunan Province, and to examine the correlation between deltamethrin resistance and mutation sites in the sodium iron channel gene in Rh. microplus.

METHODS

Rh. microplus was sampled from multiple yellow cattle farms in Huaihua City, Hunan Province from June to September 2022, and the level of resistance to deltamethrin was determined in ticks using the adult immersion test. The sodium iron channel domain III gene was amplified in deltamethrin-resistant and wild-type Rh. microplus using PCR assay. Following sequencing and sequence alignment, mutation sites were detected in bases. The sodium iron channel domain III gene in Rh. microplus was translated, and the signal peptide, transmembrane domain, and phosphorylation and glycosylation sites were detected in amino acid sequences. The tertiary structures of the sodium iron channel domain III protein of deltamethrin-resistant and wild-type Rh. microplus were deduced and compared, and the association be tween mutation sites in bases and resistance to deltamethrin was examined in Rh. microplus according the level of deltamethrin resistance, sequence alignment and protein tertiary structure.

RESULTS

The median (LC50) and 95% lethal concentrations (LC95) of deltamethrin were 121.39 mg/L and 952.61 mg/L against Rh. microplus, with a resistance factor of 9.24 and level II resistance. The sequence of the sodium ion channel domain III gene was 1 010 bp in size, and mutation sites were detected in two neighboring bases in the sequence of the sodium ion channel domain III gene in deltamethrin-resistant Rh. microplus. Although no signal peptides were found in the sodium iron channel domain III protein of deltamethrin-resistant or wild-type Rh. microplus, 6 trans-membrane domains, 42 phosphorylation sites and 8 glycosylation sites were identified, with a significant difference in the tertiary structure of the sodium iron channel domain III protein between deltamethrin-resistant and wild-type Rh. microplus.

CONCLUSIONS

Level II resistance to deltamethrin is detected in Rh. microplus in Huaihua City, Hunan Province, and two mutation sites that correlate with the emergence of deltamethrin resistance are identified in the sequence of the sodium iron channel domain III gene in deltamethrin-resistant Rh. microplus.

Determination of 25 quaternary ammonium compounds in sludge by liquid chromatography-mass spectrometry

With the pandemic of COVID-19, the application of quaternary ammonium compounds (QACs), which can be used in SARS-CoV-2 disinfection products, has increased substantially. QACs cumulated in sewer system are ultimately deposited and enriched in sludge. QACs in the environment can adversely affect human health and the environment. In this study, a liquid chromatography-mass spectrometry method was established for the simultaneous determination of 25 QACs in sludge samples. Ultrasonic extraction and filtration of the samples was performed using a 50 mM hydrochloric acid-methanol solution. The samples were separated by liquid chromatography and detected in multiple reaction monitoring mode. The matrix effects of the sludge on the 25 QACs ranged from - 25.5% to 7.2%. All substances showed good linearity in the range of 0.5-100 ng/mL, with all determination coefficients (R2) greater than 0.999. The method detection limits (MDLs) were 9.0 ng/g for alkyltrimethylammonium chloride (ATMAC), 3.0 ng/g for benzylalkyldimethylammonium chloride (BAC), and 3.0 ng/g for dialkyldimethylammonium chloride (DADMAC). The spiked recovery rates were in the range of 74-107%, while the relative standard deviations were in the range of 0.8-20.6%. Considering its sensitivity, accuracy, and easy operation, the proposed method in this study was used to determine 22 sludge samples collected from a comprehensive wastewater treatment plant. The results showed that the concentrations of ΣATMACs, ΣBACs, and ΣDADMACs were 19.684, 3.199, and 8.344 μg/g, respectively. The main components included ATMAC-C16, ATMAC-C18, ATMAC-C20, ATMAC-C22, BAC-C12, and DADMAC-C18:C18, with concentrations exceeding 1.0 μg/g. The concentration relationships of different components in the congeners showed that some components were of similar origin.

Evaluation of the health risk using multi-pollutant air quality health index: case study in Tianjin, China

Introduction

Air pollution imposes a significant burden on public health. Compared with the popular air quality index (AQI), the air quality health index (AQHI) provides a more comprehensive approach to measuring mixtures of air pollutants and is suitable for overall assessments of the short-term health effects of such mixtures.

Methods

We established an AQHI and cumulative risk index (CRI)-AQHI for Tianjin using single-and multi-pollutant models, respectively, as well as environmental, meteorological, and daily mortality data of residents in Tianjin between 2018 and 2020.

Results and discussion

Compared with the AQI, the AQHI and CRI-AQHI established herein correlated more closely with the exposure-response relationships of the total mortality effects on residents. For each increase in the interquartile range of the AQHI, CRI-AQHI and AQI, the total daily mortality rates increased by 2.06, 1.69 and 0.62%, respectively. The AQHI and CRI-AQHI predicted daily mortality rate of residents more effectively than the AQI, and the correlations of AQHI and CRI-AQHI with health were similar. Our AQHI of Tianjin was used to establish specific (S)-AQHIs for different disease groups. The results showed that all measured air pollutants had the greatest impact on the health of persons with chronic respiratory diseases, followed by lung cancer, and cardiovascular and cerebrovascular diseases. The AQHI of Tianjin established in this study was accurate and dependable for assessing short-term health risks of air pollution in Tianjin, and the established S-AQHI can be used to separately assess health risks among different disease groups.

[A multicenter epidemiological study of acute bacterial meningitis in children]

Objective: To analyze the clinical epidemiological characteristics including composition of pathogens , clinical characteristics, and disease prognosis acute bacterial meningitis (ABM) in Chinese children. Methods: A retrospective analysis was performed on the clinical and laboratory data of 1 610 children <15 years of age with ABM in 33 tertiary hospitals in China from January 2019 to December 2020. Patients were divided into different groups according to age,<28 days group, 28 days to <3 months group, 3 months to <1 year group, 1-<5 years of age group, 5-<15 years of age group; etiology confirmed group and clinically diagnosed group according to etiology diagnosis. Non-numeric variables were analyzed with the Chi-square test or Fisher's exact test, while non-normal distrituction numeric variables were compared with nonparametric test. Results: Among 1 610 children with ABM, 955 were male and 650 were female (5 cases were not provided with gender information), and the age of onset was 1.5 (0.5, 5.5) months. There were 588 cases age from <28 days, 462 cases age from 28 days to <3 months, 302 cases age from 3 months to <1 year of age group, 156 cases in the 1-<5 years of age and 101 cases in the 5-<15 years of age. The detection rates were 38.8% (95/245) and 31.5% (70/222) of Escherichia coli and 27.8% (68/245) and 35.1% (78/222) of Streptococcus agalactiae in infants younger than 28 days of age and 28 days to 3 months of age; the detection rates of Streptococcus pneumonia, Escherichia coli, and Streptococcus agalactiae were 34.3% (61/178), 14.0% (25/178) and 13.5% (24/178) in the 3 months of age to <1 year of age group; the dominant pathogens were Streptococcus pneumoniae and the detection rate were 67.9% (74/109) and 44.4% (16/36) in the 1-<5 years of age and 5-<15 years of age . There were 9.7% (19/195) strains of Escherichia coli producing ultra-broad-spectrum β-lactamases. The positive rates of cerebrospinal fluid (CSF) culture and blood culture were 32.2% (515/1 598) and 25.0% (400/1 598), while 38.2% (126/330)and 25.3% (21/83) in CSF metagenomics next generation sequencing and Streptococcus pneumoniae antigen detection. There were 4.3% (32/790) cases of which CSF white blood cell counts were normal in etiology confirmed group. Among 1 610 children with ABM, main intracranial imaging complications were subdural effusion and (or) empyema in 349 cases (21.7%), hydrocephalus in 233 cases (14.5%), brain abscess in 178 cases (11.1%), and other cerebrovascular diseases, including encephalomalacia, cerebral infarction, and encephalatrophy, in 174 cases (10.8%). Among the 166 cases (10.3%) with unfavorable outcome, 32 cases (2.0%) died among whom 24 cases died before 1 year of age, and 37 cases (2.3%) had recurrence among whom 25 cases had recurrence within 3 weeks. The incidences of subdural effusion and (or) empyema, brain abscess and ependymitis in the etiology confirmed group were significantly higher than those in the clinically diagnosed group (26.2% (207/790) vs. 17.3% (142/820), 13.0% (103/790) vs. 9.1% (75/820), 4.6% (36/790) vs. 2.7% (22/820), χ²=18.71, 6.20, 4.07, all P<0.05), but there was no significant difference in the unfavorable outcomes, mortility, and recurrence between these 2 groups (all P>0.05). Conclusions: The onset age of ABM in children is usually within 1 year of age, especially <3 months. The common pathogens in infants <3 months of age are Escherichia coli and Streptococcus agalactiae, and the dominant pathogen in infant ≥3 months is Streptococcus pneumoniae. Subdural effusion and (or) empyema and hydrocephalus are common complications. ABM should not be excluded even if CSF white blood cell counts is within normal range. Standardized bacteriological examination should be paid more attention to increase the pathogenic detection rate. Non-culture CSF detection methods may facilitate the pathogenic diagnosis.

[Relationship between nutritional factors and clinical outcome in children with tuberculous meningitis]

Objective: To investigate the relationship between nutritional risk status and clinical outcome in children with tuberculous meningitis (TBM). Methods: The clinical data (basic information, clinical symptoms and laboratory test results) of 112 patients with TBM, who were admitted to Department of Pediatric Infectious Diseases of West China Second Hospital of Sichuan University,from January 2013 to December 2020 were retrospectively analyzed. The patients were divided into the nutritional risk group and the non-nutritional risk group according to the assessment of the nutritional risk by the STRONGkids Scale. The variables of basic information, clinical symptoms and laboratory test measurements etc. were compared between the two groups by using Student t test, Rank sum test or Chi-square test. Multivariate Logistic regression analysis were used to analyze nutritional risk factors. Results: Among 112 patient with TBM, 55 were males and 57 females. There were 62 cases in the nutritional risk group and 50 cases in the non-nutritional risk group. The proportion of cases with nutritional risk was 55.4% (62/112). Patients in the nutritional risk who lived in rural areas, had symptoms of brain nerve damage, convulsions, emaciation and anorexia, with a diagnosis time of ≥21 days, and the level of cerebrospinal fluid (CSF) protein were all higher than those in the non-nutritional risk group ((50 cases (80.6%) vs. 32 cases (64.0%), 20 cases (32.3%) vs.8 cases (16.0%), 33 cases (53.2%) vs. 15 cases (30.0%), 30 cases (48.4%) vs. 2 cases (4.0%), 59 cases (95.2%) vs. 1 case (2.0%),41 cases (66.1%) vs.18 cases (36.0%), 1 406 (1 079, 2 068) vs. 929 (683, 1 208) mg/L, χ²=3.91, 3.90, 6.10, 26.72, 98.58, 10.08, Z=4.35, all P<0.05). The levels of serum albumin,hemoglobin,lymphocyte count, white blood cell count, and CSF glucose were significantly lower in patients with nutritional risk ((36±5) vs. (41±4) g/L, (110±17) vs. (122±14) g/L, 1.4 (1.0, 2.0)vs. 2.3 (1.6, 3.8)×10⁹/L, 7.8 (6.3, 10.0)×10⁹ vs. 10.0 (8.3, 12.8)×10⁹/L, 1.0 (0.8, 1.6) vs. 2.1 (1.3, 2.5) mmol/L, t=-6.15, -4.22, Z=-4.86, -3.92, -4.16, all P<0.05).Increased levels of serum albumin (OR=0.812, 95%CI:0.705-0.935, P=0.004) and lymphocyte count (OR=0.609, 95%CI:0.383-0.970, P=0.037) may reduce the nutritional risk of children with TBM; while convulsions (OR=3.853, 95%CI:1.116-13.308, P=0.033) and increased level of CSF protein (OR=1.001,95%CI:1.000-1.002, P=0.015) may increase the nutritional risk of children with TBM. Similarly, the rate of complications and drug-induced liver injury was higher in the nutritional risk group (47 cases (75.8%) vs. 15 cases(30.0%), 31 cases (50.0%) vs.8 cases (16.0%), χ²=23.50, 14.10, all P<0.05). Moreover, the length of hospital stay was also longer in the nutritional risk group ((27±13) vs. (18±7) d, t=4.38, P<0.05). Conclusions: Children with TBM have a high incidence of nutritional risk. Convulsive, the level of serum albumin, the level of lymphocyte count and CSF protein may affect the nutritional risk of children with TBM. The nutritional risk group has a high incidence of complications and heavy economic burden.It is necessary to carry out nutritional screening and nutritional support for children with TBM as early as possible.

[Genetic analysis of mitochondrial pcox1 and ribosomal 18S rRNA genes in Eurytrema pancreaticum isolates from goats in Huaihua City, Hunan Province]

OBJECTIVE

To investigate the genetic variation of Eurytrema pancreaticum isolated from goats in Huaihua City, Hunan Province.

METHODS

The partial sequence of mitochondrial cytochrome I (pcox1) and ribosomal 18S rRNA genes were amplified using a PCR assay in E. pancreaticum isolates from goats in Huaihua City, Hunan Province, and the PCR amplification products were sequenced. Then, the gene sequences were subjected to genetic variation and phylogenetic analyses.

RESULTS

The sequences of the pcox1 and 18S rRNA genes were 430 bp and 1 857 bp in length in 18 E. pancreaticum isolates from goats in Huaihua City, Hunan Province, and there were 14 and 35 variation sites in pcox1 and 18S rRNA gene sequences, with intra-species genetic variations of 0 to 1.4% and 0 to 0.8%, respectively. The sequences of pcox1 and 18S rRNA genes had 99.0% to 99.8% and 99.5% to 99.8% homologies with those from E. pancreaticum Chinese strain recorded in the GenBank database. Consistent phylogenetic analysis results were found based on pcox1 and 18S rRNA genes. The 18 E. pancreaticum isolates from goats in Huaihua City were clustered into a clade with the known E. pancreaticum isolates registered in GenBank, and the clade with these 18 E. pancreaticum isolates was close to the clades with Eurytrema species and far from the clades with other trematodes.

CONCLUSIONS

The E. pancreaticum isolates from goats have a low genetic variation in Huaihua City, Hunan Province. Mitochondrial pcox1 and ribosomal 18S rRNA genes may serve as molecular markers for the studies on the genetic variation in goat-derived E. pancreaticum.

Characterization of the volatile compounds emitted from municipal solid waste and identification of the key volatile pollutants

Gaseous emissions from municipal solid waste (MSW) have raised many concerns and complaints. Identifying the key volatile pollutants in the complex gaseous emissions from MSW is significant for the efficient mitigation of their odor nuisances and health risks. For this purpose, we present an integrated investigation of the key volatile pollutants in the gaseous emissions of MSW from the perspectives of emission patterns, odor concentrations and health risks. Air samples were collected during four different emission stages of the waste matrix for both chemical and olfactometric analyses. The total chemical concentrations of the volatile compounds in the air samples were in the range of 21.49 mg m^-3 to 295.61 mg m^-3, and the odor concentrations varied from 1122 ou_E m^-3 to 17,782 ou_E m^-3. The odor concentrations in the air samples were well correlated with the odor activity values (OAVs) of sulfur compounds, oxygenated compounds and ammonia (r = 0.922, 0.879 and 0.780, respectively, for n = 17 and p < 0.01). Moreover, from an integrated perspective involving chemical emissions, the proportions of odor concentrations and health risks, ethanol, methyl mercaptan and hydrogen sulfide were identified as the key volatile pollutants in the gaseous emissions from the waste matrix during the airtight storage stage, and dimethyl disulfide, 1,2-dichloroethane and trichloroethylene were the key volatile pollutants during the ventilation stage.

High level of source-specific particulate matter air pollution associated with cardiac arrhythmias

Epidemiological evidence linking source-specific ambient particulate matter with aerodynamic diameter <2.5 μm (PM_2.5) and cardiac arrhythmias is limited. In this study, we investigated the impact of source-specific PM_2.5 on cardiac arrhythmias in a panel of forty-five healthy adults living in Beijing, China, between 2015 and 2016. Repeated measures of 24-hour electrocardiograms were conducted during clinical visits, and daily counts of four arrhythmia events including supraventricular premature beat (SVPB), atrial tachycardia (AT), premature ventricular contraction (PVC) and ventricular tachycardia (VT) were recorded. One hundred forty-seven constituents in PM_2.5 were analyzed for collected particulate samples, in which fifty-six of them above laboratory detection limits were selected for source apportionment analysis using positive matrix factorization. The average contributions of identified five major sources to PM_2.5 were 45.9% from secondary nitrate/sulfate, 18.0% from coal combustion, 16.9% from crustal soil, 13.8% from biomass burning, and 5.4% from cooking. Generalized estimating equation models were used to estimate relative risks (RR) of arrhythmias in association with interquartile-range (IQR) increases in PM_2.5 constituents and specific sources. Total PM_2.5 mass as well as several combustion related constituents were found of significant impacts on increased risks of arrhythmia events. Among the identified sources of PM_2.5, coal burning has been found the major source that associated with increased risks of SVPB, PVC and VT with RR of 1.19 [95% confidence intervals (CI): 1.04, 1.36] to 1.64 (95% CI: 1.35, 2.00). PM_2.5 from combustion related secondary nitrate/sulfate was also found of significant impact on SVPB and AT, followed by PM_2.5 from biomass burning and crustal soil. Our results indicated that PM_2.5 from anthropogenic activity related sources were most responsible for increased risks of arrhythmia events. Our findings enhance the understanding of increased risks of arrhythmias from exposure to PM_2.5, and provide evidence on source-specific PM control priorities.

Assessment of the health risks and odor concentration of volatile compounds from a municipal solid waste landfill in China

Municipal solid waste (MSW) landfills are a source of odorous and toxic compounds. In this work, we present an integrated assessment of the odor concentration and human health risks of volatile compounds to evaluate the environmental quality at a MSW landfill. Air samples were collected seasonally from six areas of the landfill with different functions. The total concentrations of the compounds ranged from 204.0 to 7426.7 μg m^-3, and the concentrations in temporarily and permanently capped areas were 50.3 and 83.4% lower than those in the tipping area, respectively. The odor concentration was greatest at the leachate collection tank (1732-6254 ou_E m^-3) and tipping area (1573-4113 ou_E m^-3) and was mainly caused by hydrogen sulfide (57.9 and 49.1%, respectively). Moreover, the odor concentration was positively correlated with the temperature (r = 0.500, p < 0.05, n = 24). Although the non-carcinogenic (HI) and carcinogenic (R) risks of most compounds were largely below the acceptable levels (HI = 1, R = 1.0E-6), HI values of hydrogen sulfide (2.3), trichloropropane (2.0), and naphthalene (1.2) as well as R values of naphthalene (1.3E-4) and trimethylbenzene (1.2E-4) in the waste areas exceeded acceptable levels. Moreover, the cumulative HI (2.5-5.7) and R (1.0E-04 to 3.4E-04) in the waste areas should receive special attention since they were above acceptable levels during all of the seasons. Aromatic and halogenated compounds dominated the cumulative R, accounting for 79 and 21% of the total, on average, while for the cumulative HI, sulfur compounds contributed the most (67%).

Effects of oral contraceptives on ovulation induction in in vitro fertilization patients with premature ovarian insufficiency

OBJECTIVE

To report a case series of in vitro fertilization patients with premature ovarian insufficiency, who were treated with oral contraceptives to reduce follicle stimulating hormone levels.

METHOD

This was a consecutive case series in a tertiary teaching hospital in China. Twenty-two women with refractory and idiopathic premature ovarian insufficiency were administered a drospirenone/ethinylestradiol oral contraceptive orally. The main outcome measures were the number of oocytes retrieved and the number of embryos frozen.

RESULTS

There were total 106 oral contraceptive treatment cycles and 53 oocyte retrieval cycles in 20 patients (91%, 20/22; 2.4 cycles per woman, 53/22). The total number of oocytes retrieved was 48 in 17 patients (77%, 17/22; 2.2 oocytes per woman, 48/22), and the total number of embryos frozen was 33 in 16 patients (73%, 16/22; 1.5 embryos per woman, 33/22).

CONCLUSION

Oral contraception may be an effective method to induce ovulation for some patients with premature ovarian insufficiency.

Analysis of specialized nursing on respiratory functions in thoracotomy patients

To analyze the nursing effect on the respiratory function of thoracotomy patients, sixty thoracotomy hospitalized patients were studied. The subjects were divided into a normal group (A) and an observation group (B). The patients in group A received routine nursing only, while those in group B received chest physiotherapy as well as routine nursing. Afterwards, the respiratory function indicators of the two groups were compared and a data analysis was performed. The results showed that the partial pressure of oxygen (PO2) value of the patients in group B was greater than that of the patients in group A while the partial pressure of carbon dioxide (PCO2) value in group B was smaller than that in group A, and there was a significant difference between the two groups (p less than 0.05). The vital capacity under normal circumstances and forced breathing of group B were greater than that of group A and the difference was statistically significant (p less than 0.05). The incidence of complications (atelectasis, respiratory infections, pleural effusion) was statistically significant between the two groups (p less than 0.05). The degree of autonomic respiratory dysfunction in group B was lower than that in group A, and there was a significant difference (p less than 0.05), suggesting that the respiratory function in patients receiving chest physiotherapy improved significantly.

[Clinical characteristics and therapeutic effect of drug-resistant tuberculosis in children]

Objective: To explore the clinical characteristics of drug-resistant tuberculosis (TB) in children and to study the effectiveness of second-line anti-TB therapy for children and to examine the incidence of adverse drug reactions. Method: Retrospective research was conducted. The clinical records of children in West China Second Hospital diagnosed as drug-resistant TB from January 2010 to June 2014 were investigated.The clinical characteristics and risk factors were analyzed retrospectively. Treatment effect at discharge was examined as a short-term outcome indicator to evaluate the effectiveness of second-line anti-TB therapy and the incidence of adverse drug reactions. χ(2) test was used. Result: Forty-six patients were diagnosed as drug-resistant TB in 443 children infected with TB, with a 10.4% resistance rate. The 46 children included 26 male and 20 female patients, aged from one month and 28 days to 17 years and 5 months, with the average age (8.4±4.5) years, >7 to 14 years old patients as the biggest part(25 patients, 54.3%). Among the 46 children, 20 patients(43.5%)had close contact with TB patients, of whom 12 patients (60.0%) contacted with family members (including parents, brothers and sisters and grandparents living together) and 8 patients(40.0%) contacted with patients from outside family (such as relatives or neighbors). Moreover, 11 cases (23.9%) were under initial treatment and 35 cases (76.1%) were retreated.From 2010 to 2014, the number of cases of initial and retreated patients had no significant difference(0 and 1, 1 and 13, 4 and 7, 4 and 11, 2 and 3 cases, χ(2)=3.255, P=0.196). Among retreated patients, 31.4% (11/35) had irregular treatment before.Until discharge, the effective rate was 87.0% (40/46), while the incidence rate of adverse drug reaction was 10.9%(5/46). Conclusion: The therapy for drug-resistant TB is effective and the incidence of adverse drug reaction is relatively low.

Comparison of laparoscopy and open surgery in treating severe acute pancreatitis and its relative aftercare

This study was designed to determine the effects and compare laparoscopic intervention and open surgery in treating severe acute pancreatitis (SAP) and its relative aftercare, to improve the overall treatment of SAP. Ninety patients with SAP were enrolled from the 2nd Affiliated Hospital of Harbin Medical University from 2008 to 2014 and divided into a laparoscopic intervention group (25 cases) and an open surgery group (65 cases). Patients were asked for clinical symptoms, general hospital information, laboratory inspection, imageological examination, local and systemic complications, treatment and outcome. SAP patients’ relevant clinical indicators were compared between the two groups before and after the operation. Results revealed that there was no statistical significance in lesion range and main scoring indexes for reflecting the severity of the disease. For both groups statistical significance was found in blood loss (285.3±79.8 mL vs 362±91.6 mL), intensive care unit (ICU) monitoring time (9.04±6.35 d vs 12.48±8.34 d) and service time of breathing machine (9.47±6.24 d vs 12.98±8.25 d), and the laparoscopic operation group was superior to the open surgery group (p < 0.05). Besides, the laparoscopic operation group was also superior to the open surgery group in demand for main analgesics one week after the operation, as well as for recovery rate and incidence of complications (p < 0.05). Thus, it can be concluded that patients undergoing laparoscopic intervention are less likely to develop pulmonary infection and more likely to be cured in comparison with patients who receive open surgery. In addition, laparoscopic intervention results in less damage, lighter pain and fewer complications compared with open surgery.

Propionic acid and its esterified derivative suppress the growth of methicillin-resistant Staphylococcus aureus USA300

Previously, we demonstrated that Propionibacterium acnes, a human skin commensal bacterium, ferments glycerol into short-chain fatty acids, including propionic acid. Propionic acid suppressed the growth of Staphylococcus aureus USA300, a community-acquired methicillin-resistant bacterium, in vitro and in vivo. In this study, it is demonstrated that the anti-USA300 activity of propionic acid persisted after buffering the acid with 4-(2-hydroxyethyl)-1- piperazineethanesulfonic acid. This suggests that the growth suppression of USA300 mainly resulted from the antimicrobial activity of propionic acid per se and not from the acidity of the medium. In addition, proprionic acid significantly reduced the intracellular pH of USA300 and exhibited broad-spectrum antimicrobial activity against Escherichia coli and Candida albicans. P. acnes showed a higher tolerance to propionic acid. Next, an esterified derivative of propionic acid was synthesised. Propionic acid and the esterified derivative were equivalent in their efficacy to suppress the growth of USA300 in vitro. The esterified derivative thus provides an alternative to propionic acid as an antimicrobial agent against S. aureus.

Porphyrin metabolisms in human skin commensal Propionibacterium acnes bacteria: potential application to monitor human radiation risk

Propionibacterium acnes (P. acnes), a Gram-positive anaerobic bacterium, is a commensal organism in human skin. Like human cells, the bacteria produce porphyrins, which exhibit fluorescence properties and make bacteria visible with a Wood's lamp. In this review, we compare the porphyrin biosynthesis in humans and P. acnes. Also, since P. acnes living on the surface of skin receive the same radiation exposure as humans, we envision that the changes in porphyrin profiles (the absorption spectra and/or metabolism) of P. acnes by radiation may mirror the response of human cells to radiation. The porphyrin profiles of P. acnes may be a more accurate reflection of radiation risk to the patient than other biodosimeters/biomarkers such as gene up-/down-regulation, which may be non-specific due to patient related factors such as autoimmune diseases. Lastly, we discuss the challenges and possible solutions for using the P. acnes response to predict the radiation risk.

MiR-135a functions as a selective killer of malignant glioma

Glioma is the most common and fatal primary brain tumor. Thus far, therapeutic strategies to efficiently and specifically antagonize glioma are limited and poorly developed. Here we report that glia-enriched miR-135a, a microRNA that is dramatically downregulated in malignant glioma and correlated with the pathological grading, is capable of inducing mitochondria-dependent apoptosis of malignant glioma by regulating various genes including STAT6, SMAD5 and BMPR2, as well as affecting the signaling pathway downstream. Moreover, this lethal effect is selectively towards malignant glioma cells, but not neurons and glial cells, through a novel mechanism. Our findings suggest an important role of miR-135a in glioma etiology and provide a potential candidate for malignant glioma therapy.

The relationship between dental caries status and dental plaque urease activity

INTRODUCTION

Ammonia production from the metabolism of urea by urease enzymes of oral bacteria moderates plaque acidification and may inhibit dental caries, as suggested by in vitro studies and indirect clinical observations. The objective of this study was to examine the relationship of urease activity with dental caries at the clinical level.

METHODS

Urease activity was measured in dental plaque and saliva samples from 25 caries-free subjects (CF) and in eight subjects with six or more open caries lesions (CA). Plaque and saliva collection was repeated for each subject 1 week later using identical procedures.

RESULTS

Urease-specific activity in the dental plaque of CF subjects was significantly higher compared to that in the subjects with caries. The association of low plaque urease levels with increased caries was further supported by odds ratio analysis using different plaque urease cut-off points. Using a receiver operating characteristic curve it was estimated that there was an approximately 85% probability of correctly classifying the subjects as CA or CF based on the relative ordering of their plaque urease activity levels. No statistically significant differences were observed in salivary urease activity.

CONCLUSION

This study suggests that loss of alkali-generating potential of tooth biofilms via the urease pathway has a positive relationship to dental caries.

[Study on etiologic agents of vaginitis]

In order to provide scientific basis for preventing and curing vaginitis, etiologic agents were examined in 354 patients with vaginitis and 115 healthy women using rapid and reliable laboratory methods. The inducements of vaginitis were analysed. The results showed that candida was only detected for the normal control group. Bacteria, candida and trichomonas were the commonest causes of vaginitis. With the increasing ages of patients with vaginitis, the incidence rates of all kinds of vaginitis were lowered. Vaginitis is associated with pregnancy, using antibiotics and contraceptive, or sexual activity.

[Effect of nitric oxide on HSV-1 infection of HeLa cells and Vero-E6 cells]

The effects of nitric oxide(NO) on HSV-1 infection of HeLa cell line and Vero-E6 cell line were investigated in this study. The titers of HSV-1 in supernatants from infected culture of Vero-E6 cells were decreased by a NO donor, sodium nitroprusside(SNP), in a dose-dependent manner, while the control compound potassium ferricyanide (KFC) had no effect. However, SNP had no effect on that of HeLa cells. The results reaffirm the antiviral effect of NO and suggest that the susceptibility of different cell lines to the effect of NO might be varied.

Water sorption and mechanical behaviour of cosmetic direct restorative materials in artificial saliva

OBJECTIVES

To evaluate the water sorption and mechanical behaviour of a compomer in comparison with those of its nominal forerunners, a filled resin restorative material and a conventional glass ionomer cement.

METHOD

Compomer (Dyract AP) (D-AP), filled resin (SureFil) (SF), and glass ionomer (ChemFlex) (CF) (all Dentsply, Addlestone, UK) restorative materials were tested. Forty bar specimens (26x1.5x1.0mm(3)) of each material were prepared according to the manufacturer's instructions and randomly distributed into eight groups: dry air (22% RH), saturated water vapour (WV) (100% RH), and five in artificial saliva (AS) at pH6, all at 37 degrees C, as well as untreated control (UC) (23 degrees C, 50% RH). Water sorption was assessed gravimetrically; flexural strength and elastic modulus were determined in three-point bend. The control group was tested at 24h; AS groups were separately tested after 0.5, 1, 3, 6 and 9 months; the other two at 9 months.

RESULTS

Mass gain for SF, D-AP and CF in AS was up to 0.17%, 1.2% and 7.0%, respectively. CF showed a marked decrease of strength in AS compared with other groups, followed by a gradual slight rise to a peak at 3 months. Unlike SF and CF, whose flexural strength remained relatively stable, that of D-AP showed a sharp decline from the 1 month peak (P=6x10(-7)) after 6 months in AS. D-AP also showed a slight decline in flexural modulus from a peak, that of SF was quite stable, while CF showed no peak. The values of flexural strength for both CF and D-AP at 9 months were significantly lower in AS than WV, but SF showed no such difference.

SIGNIFICANCE

Materials intended for service in the mouth must be stored in a realistic medium if the results of testing are to be interpretable. Dyract AP, a compomer, does not seem suitable for application in stress bearing areas as is currently recommended by its manufacturer. The rapid decline in flexural strength after 1 month of exposure to AS and its progressive fall in flexural modulus suggest a progressive deterioration of the material and this necessitates re-examination of the chemistry of compomers, if the behaviour is typical of the class.

Sulfur-rich zinc chemistry: new tris(thioimidazolyl)hydroborate ligands and their zinc complex chemistry related to the structure and function of alcohol dehydrogenase

The 1-substituted tris(2-thioimidazolyl)hydroborate ligands Tt(R) were prepared as the potassium salts from KBH(4) and the corresponding 1-R-2-thioimidazole for R = t-Bu and C(6)H(4)-p-CH(CH(3))(2) (Cum). Their reactions with zinc salts yielded the tetrahedral complexes Tt(R)Zn-X with X = F, Cl, ONO(2) and (Tt(t)()(-)(Bu))(2)Zn. With zinc perchlorate the labile perchlorate complexes Tt(R)Zn-OClO(3) were obtained. They served as starting materials for the incorporation of substrates which are relevant for the chemistry of horse liver alcohol dehydrogenase: Ethanol led to [Tt(t)()(-Bu)Zn.EtOH] ClO(4).EtOH, p-nitrophenol (NitOH) yielded Tt(Cum)Zn-ONit. Pyridine-2-carbaldehyde and salicylic aldehyde were incorporated as N(pyridine) and O(phenolate) coligands with possible additional O(aldehyde) coordination. Substituted pyridyl methanols (R-PyCH(2)OH) yielded the trinuclear complexes [(Tt(t)()(-Bu))(2)Zn(3)(R-PyCH(2)O)(2)] (ClO(4))(2) with bridging Tt and pyridylmethoxide ligands. Preliminary experiments on the functional modeling of alcohol dehydrogenase have shown that TtZn complexes promote both the dehydrogenation of 2-propanol and the hydrogenation of pentafluorobenzaldehyde.

Effects of two different growth media on the postantifungal effect induced by polyenes on Candida species

There are no data on the effects of different growth media on polyene-induced postantifungal effect (PAFE) in Candida species. Hence, the nystatin- and amphotericin B-induced PAFEs in six Candida species (26 isolates) grown in Sabouraud's dextrose broth (SAB) and RPMI broth were evaluated, following limited exposure to the MICs of the two polyenes, using an automated turbidometric method. For nystatin, PAFE varied between 1.88 and 4.87 h in SAB and 0.66 and 6.89 h in RPMI, and for amphotericin B, the equivalent values were 3.13 to 10.98 h in SAB and 0.97 to 7.01 h in RPMI. These highly significant (P < 0.001) variations in the PAFE with both drugs, noted with most Candida strains grown in different media, call for standardization of intralaboratory methodology in measuring this parameter in order to obtain universally comparable data.

[Clinical significance of elevated serum sICAM-1 in patients with nasopharyngeal carcinoma]

OBJECTIVE

To study the expression of serum sICAM-1(soluble intercellular adhesion molecule-1) and tissue ICAM-1 in nasopharyngeal carcinoma and its clinical significance.

METHODS

Expression of ICAM-1 in frozen sections of 20 normal nasopharyngeal mucosa and 54 nasopharyngeal carcinoma samples were studied with immunohistochemical technique, and levels of serum sICAM-1 in 54 patients with nasopharyngeal carcinoma (NPC group) and 32 healthy adults (normal group) by ELISA.

RESULTS

Positive expression (45/54) of tissue ICAM-1 and levels (2,044.48 +/- 640.05) microgram/L of serum sICAM-1 in NPC group were significantly higher than that of 2/20 and (313.70 +/- 114.98) microgram/L in normal group (P < 0.01, respectively), and there was a positive relationship between the expression of tissue ICAM-1 and levels of serum sICAM-1 in nasopharyngeal carcinoma(P < 0.05). The levels (2,177.31 +/- 642.13) microgram/L of serum sICAM-1 in patients with III-IV stages were higher than those (1,847.25 +/- 308.15) microgram/L in I-II stages (P < 0.05), and those (1,678.89 +/- 685.01) microgram/L in patients with no lymph node metastasis lower than that (2,134.34 +/- 609.60) microgram/L in lymph node metastasis (P < 0.05). The levels of serum sICAM-1 decreased significantly from (2,211.42 +/- 717.59) microgram/L to (926.55 +/- 207.72) microgram/L in disappearance of tumor and metastatic lymph node after radiotherapy (P < 0.01).

CONCLUSION

sICAM-1 might be involved in the cellular immunopathogenesis of nasopharyngeal carcinoma, and the measurement of the serum sICAM-1 may reflect ability of neoplasm cell in freedom from host immunological surveillance. Dynamic measurement of serum sICAM-1 may be a useful objective index to evaluate NPC prognosis and curative effects.

[The complication of multiple system organs failure in pregnancy: a clinical analysis of 13 cases]

OBJECTIVE

To find out the features and causes of the complications of multiple system organs failure (MSOF) in pregnancy and increase the level of its prevention and treatment.

METHODS

A retrospective study was carried out on 13 cases with the complication of MSOF in pregnancy admitted between Feb 1992-Jun 1999.

RESULTS

There were two or more organs or systems function failure in the pregnancy. Four cases induced by infection, 5 cases induced by heart diseases, 3 cases induced by pregnancy induced hypertension, 1 case induced by amniotic fluid embolism. 12 of 13 were cured. 1 was died. Among them one infant was died.

CONCLUSIONS

During the treatment of pregnancy with multiple system organs failure, it is important to control the causes and inducements. It is forcible to terminate pregnancy in time and choose a best style of delivery. It is better to keep watch on saving multiple system organs function.

Fluoride distribution in sound and carious root tissues of human teeth

Proton probe analysis has been used to provide for the first time quantitative F concentration data in carious root tissues from subjects consuming water containing 1 ppm F. In small lesions at the neck of the tooth with minimal tissue loss the F concentration was significantly higher at the outer lesion edge than at the outer edge of adjacent sound root tissue. In one sample with high F values the lesion edge had 19,000 ppm F and the adjacent sound root surface 5,400 ppm F microg F/g apatite). In large lesions with extensive cavitation F was again concentrated in the outer edge of the lesion and was significantly higher (1,800-4,100 ppm) than in adjacent sound inner dentine (190-290 ppm). Fluoride concentrations varied markedly along the outer edge of both normal and carious root tissues. Fluoride increase at the lesion edge is not an effect of tissue shrinkage but probably a result of remineralisation events during caries. This additional F may be expected to increase tissue resistance to further acid attacks.

Versatile and efficient solid-phase syntheses of pyrazoles and isoxazoles

[reaction: see text] Condensation of aromatic or aliphatic esters with resin-supported acetyl carboxylic acids 2, followed by cyclization with hydrazines or hydroxylamine, activation of the linker, and cleavage using amines provides highly substituted, isomeric pyrazoles or isoxazoles 5. This general method gives products in excellent yields and purities in which the ratio of the two isomers can be easily controlled. A variation of this scheme generates 1,4,5- and 1,3, 4-trisubstituted pyrazoles and related isoxazoles. Post-cleavage reduction with borane converts pyrazole amides to amines such as 11.

In vitro fluoride release from aesthetic restorative materials following recharging with APF gel

In this in vitro study, the fluoride ion release from three more-viscous conventional glass ionomer cements (GICs)--ChemFlex, Fuji IX GP, Ionofil Molar--four polyacid-modified resin composites (compomers)--Dyract AP, Compoglass F, Freedom, F2000--and a hybrid resin composite--Ariston pHc--were compared. The amounts of fluoride release from 3 x 2.7 mm specimens were measured over six weeks using a fluoride ion-selective electrode. After six weeks, the specimens were recharged with 2 ml of 1.23 per cent acidulated phosphate fluoride (APF) gel for four minutes. The recharged specimens were then assessed for the amounts of fluoride release over another six weeks. Statistical analyses were performed using one-way and repeated measures ANOVA. The GICs and Compoglass F showed significantly higher initial fluoride release rates during the first two days (p < 0.05). After the first two days, fluoride release rates from all materials dropped quickly and became essentially stabilized within three-five weeks, in an exponential mode. The recharging of the specimens with APF gel caused a brief, but significant, increase in fluoride release for all materials (p < 0.05), before decreasing to previous comparable rates. Compoglass F released relatively more fluoride, and Ariston pHc relatively less, after APF gel application than before. The lowest total amounts over the study were released by Dyract AP and Freedom. The newer compomers, as well as the newer more-viscous GICs, appear to act as fluoride reservoirs to varying extents.

[Laboratory diagnosis of Chlamydia trachomatis and Ureaplasma urealyticum of chronic prostatitis]

Prostatic fluid taken from 1038 cases of chronic prostatitis were detected by fluorescent monoclonal antibody technique and isolating cultural method for Chlamydia Trachomatis (CT) and Ureaplasma Urealyticum (UU). The control group consisted of 80 cases. CT and UU were not found in control group. The positive rates of CT and UU infection were 28.4% and 33.0% respectively in the tested group whose cases were abacterial prostatitis. The results suggested that CT and UU are pathogens causing chronic abacterial prostatitis.

[Detection of interleukin-8 and nitric oxide in chronic prostatitis]

We detected levels of interleukin-8(IL-8) and nitric oxide(NO) in 62 prostatic fluids. The results were that microbiologic exam, IL-8 content, and NO level in control group were all negative; there was not significant difference on the microbiologic exam and NO level between the chronic prostatitis group and non-prostatitis group; there was significant difference between two groups of IL-8 positive ratio. These results suggest that the IL-8 detected in the prostatic fluid of patients with prostatitis may be a diagnostic indicator of prostatic infection.

[Drug resistance study and detection of methicillin-resistant staphylococci]

MRSA and MRSE were identified by detecting oxacillin resistance of 107 strains of staphylococci from clinical sources. The positive rates of MRSA were 45.2% and 16.9%, respectively among the whole number of staphylococci examined. Antibiotic-resistant strains were detected with disks by Kirby-Bauer method. All MRSA and MRSE strains were multi-resistant. Resistant rates of MRSA and MRSE were higher than MSSA and MSSE. The positive rates of beta lactamase producing in MRSA and MRSE were significantly higher than MSSA and MSSE (P< 0.05 and P< 0.01) respectively. These results indicated that MRSA and MRSE were the main pathogens in the clinical infection. MRSA and MRSE detection are important for the early diagnosis and treatment of patients with infective diseases.

[Expression and significance of p53, c-erbB2, CEA proteins in colorectal adenoma and carcinoma]

Expression of p53, c-erB2, CEA proteins in 15 cases of normal colorectal mucosa, 40 adenoma and 40 carcinoma of colon were studied with immunohistochemistry. The positive rate of p53, c-erbB2, CEA in colorectal carcinomas were significantly higher than those in adenoma. The positive rate of p53 in adenoma with severe atypical hyperplasia was higher than that in the mild (P< 0.01), and was higher in colorectal carcinomas of poor differentiation that that in the well-differentiated ones (P< 0.05). The novel type monoclonal antibody of CEA Col-1 had a high sensitivity and specificity for the tissue of colorectal carcinoma in which the positive rate was 85%. The results suggested the alteration p53, c-erbB2 are involve in the tumorgenesis and development of colorectal carcinoma; and detection of p53, c-erbB2 and CEA proteins are helpful in distinguishing benign and malignant polyps of colon.

Early postoperative changes in regional systolic and diastolic left ventricular function after transmyocardial laser revascularization: a comparison of holmium:YAG and CO2 lasers

OBJECTIVES

The purpose of this study was to determine the short-term effects of transmyocardial laser revascularization (TMR) on regional left ventricular systolic and diastolic function, myocardial blood flow (MBF) and myocardial water content (MWC).

BACKGROUND

Clinical studies of TMR have noted a significant incidence of cardiac complications in the early postoperative period. However, the early post-treatment effects of laser therapy on the myocardium and their potential contribution to postoperative cardiac morbidity are unknown.

METHODS

Swine underwent holmium:yttrium-aluminum-garnet (holmium:YAG) (n = 12) or carbon dioxide (CO2) (n = 12) laser TMR. Regional systolic function for the lased and nonlased regions was quantitated using preload recruitable work area (PRWA) and regional diastolic function with the ventricular stiffness constant alpha.

RESULTS

Preload recruitable work area was significantly decreased in the lased regions both 1 (59.8+/-13.0% of baseline, p = 0.02) and 6 h (64.2+/-9.4% of baseline, p = 0.02) after holmium:YAG TMR. This decreased PRWA was associated with a significant reduction in MBF to the lased regions (13.2% reduction at 1 h, p = 0.02; 18.4% decrease at 6 h post-TMR, p = 0.01). These changes were not seen after CO2 laser TMR. A significant increase in MWC (1.4+/-0.3% increase with holmium:YAG, p = 0.004; 1+/-0.2% increase with CO2, p = 0.002) and alpha (217.4+/-44.2% of baseline 6 h post-holmium:YAG TMR, p = 0.05; 206+/-36.7% of baseline 6 h post-CO2 TMR, p = 0.03) was seen after TMR with both lasers.

CONCLUSIONS

In the early postoperative setting, impaired regional systolic function in association with regional ischemia is seen after TMR with a holmium:YAG laser. Both holmium:YAG and CO2 lasers are associated with increased MWC and impaired diastolic relaxation in the lased regions. These changes may explain the significant incidence of early postoperative cardiac morbidity. The impact of these findings on anginal relief and long-term outcome are not known.

[Research in the relationship between Chlamydia and ureaplasma and infertility]

Samples taken from cervix and male urethra of 768 infertilitas patients were studied, and samples taken from 226 normal fertile males and females served as control. The fluorescent monoclonal antibody technique and cell culture method were used for Chlamydia trachomatis (Ct) and microbiological culture method was used for Ureaplasma urealyticum (Uu) detection. The positive rates of Ct and Uu infections were 28.64% (220/768) and 36.59% (281/768) in infertilitas group, 5.2% (14/266) and 14.28% (38/266) in control group respectively. There was significant difference between the 2 groups (P < 0.01). The results suggest that infection with Ct or Uu is one of the factors causing infertility.