Landfill is one of the important sources of carbon tetrachloride (CT) pollution, and it is important to understand the degradation mechanism of CT in landfill cover for better control. In this study, a simulated landfill cover system was set up, and the biotransformation mechanism of CT and the associated micro-ecology were investigated. The results showed that three stable functional zones along the depth, i.e., aerobic zone (0-15 cm), anoxic zone (15-45 cm) and anaerobic zone (> 45 cm), were generated because of long-term biological oxidation in landfill cover. There were significant differences in redox condition and microbial community structure in each zone, which provided microbial resources and favorable conditions for CT degradation. The results of biodegradation indicated that dechlorination of CT produced chloroform (CF), dichloromethane (DCM) and Cl^- in anaerobic and anoxic zones. The highest concentration of dechlorination products occurred at 30 cm, which were degraded rapidly in aerobic zone. In addition, CT degradation rate was 13.2-103.6 μg/(m²·d), which decreased with the increase of landfill gas flux. The analysis of diversity sequencing revealed that Mesorhizobium, Thiobacillus and Intrasporangium were potential CT-degraders in aerobic, anaerobic and anoxic zone, respectively. Moreover, six species of dechlorination bacteria and eighteen species of methanotrophs were also responsible for anaerobic transformation of CT and aerobic degradation of CF and DCM, respectively. Interestingly, anaerobic dechlorination and aerobic transformation occurred simultaneously in the anoxic zone in landfill cover. Furthermore, analysis of degradation mechanism suggested that generation of stable anaerobic-anoxic-aerobic zone by regulation was very important for the harmless removal of full halogenated hydrocarbon in vadose zone, and the increase of anoxic zone scale enhanced their removal. These results provide theoretical guidance for the removal of chlorinated pollutants in landfills.
Bacteria/metabolism* ; Biodegradation, Environmental ; Carbon Tetrachloride/metabolism* ; Methane/metabolism* ; Waste Disposal Facilities

Objective:To compare the clinical outcome between arthroscopically-assisted modified outside-in technique and inside-out technique for reconstruction of posterior cruciate ligament (PCL).Methods:A retrospective cohort study was conducted to analyze the clinical data of 53 patients with PCL rupture treated at Zhengzhou Orthopaedics Hospital from September 2015 to March 2019. There were 36 males and 17 females, at age of 21-58 years [(37.2±12.5)years]. There were 29 patients with right knee injury and 24 patients with left knee injury. All patients underwent minimally invasive arthroscopically- assisted PCL reconstruction, including the femoral tunnel established using the modified outside-in technique in 22 patients (outside-in group) and the inside-out technique with 120° of knee flexion in 31 patients (inside-out group). The two groups were compared in terms of operation time, length of femoral tunnel intraoperatively, angle between femoral tunnel and intra-articular graft at postoperative 3 days, and posterior drawer test (PDT), International Knee Documentation Committee (IKDC) score, Lysholm knee score, knee range of motion (ROM), knee extension muscle strength at the last follow-up. The complications were recorded after operation.Results:All patients were followed up for 15-38 months [(21.4±8.7) months]. There were no significant differences between the two groups in operation time and last follow-up evaluation of PDT, IKDC score, Lysholm knee score and knee ROM (all P>0.05). The length of femoral tunnel in outside-in group [(38.6±2.9)mm] was longer than that in inside-out group [(32.4±2.5)mm] ( P<0.05). The angle between femoral tunnel and intra-articular graft in outside-in group [(147.5±3.1)°] was larger than that in inside-out group [(136.4±2.6)°] ( P<0.01). The knee extension muscle strength of all patients reached grade V at the last follow-up. There were 2 patients with 5° flexion limitation in outside-in group, comparable to 3 patients with 5° flexion limitation and 1 patient with 10° flexion limitation in inside-out group ( P>0.05). No incision infection, implant loosening or injury of the extension apparatus of the knee occurred after operation. Conclusions:In treating PCL rupture, both arthroscopically-assisted modified outside-in technique and inside-out technique can achieve satisfied stability and functional recovery. However, the length and angle of femoral tunnel is more controllable when using the the modified outside-in technique.

Objective:To analyze the factors influencing functional recovery after surgery of calcaneal fracture.Methods:A retrospective analysis was performed in 1,080 eligible patients with calcaneal fracture who had been admitted to The Third Hospital of Hebei Medical University from January 1, 2018 to December 31, 2020. They were 931 males and 149 females with a mean age of 43.0 years. By the Sanders classification, there were 107 cases of type Ⅰ, 343 cases of type Ⅱ, 471 cases of type Ⅲ and 159 cases of type Ⅳ. Multiple linear regression model was used to screen out the main relevant factors affecting the postoperative functional recovery by analyzing the 18 factors which might influence the postoperative functional recovery like gender, age, Sanders type, occupation, body mass index, season, cause, hospital stay, operation method, internal fixation, preoperative combined injury, preoperative complication, anesthesia, attendance to rehabilitation institution, incision selection, waiting time, preoperative blister and reduction quality.Results:All the 1,080 patients were followed up for 17.5 months on average. The mean Creighton-Nebraska score at the last follow-up was 88.4. The univariate analyses showed statistically significant differences in the Creighton-Nebraska score among patients with different gender, age group, Sanders type, occupation, injury cause, surgical method, preoperative combined injury, incision selection and reduction quality ( P<0.05). Multiple linear regression model analysis resulted in the following regression equation: Y=107.408-4.013×gender-7.101×age-1.214×Sanders type-1.606×incision selection. Conclusions:The factors which influence the functional recovery after surgery of calcaneal fracture may be gender, age, fracture type and incision selection; the functional recovery score after surgery of calcaneal fracture may be low for female senior patients with type Ⅳ fracture and a large L-shaped incision.

Objective:To investigate the characteristics of an abnormal attachment point of the anterior horn of the medial meniscus (AHMM) by methods of arthroscopy, radiological imaging, and pathology.Methods:A total of seven cases of a rare abnormal attachment (anteromedial meniscofemoral ligament, AML) connecting the AHMM and anterior cruciate ligament (ACL) were identified in the more than six thousand arthroscopic procedures from January 2018 to April 2021. During the procedures, subtotal meniscal resection or meniscal repair was performed in all cases. Tissue removed intraoperatively was used for pathologic examination. For this study, the preoperative MRI films of these patients were retrospectively examined.Results:Finally, seven cases with diagnosed meniscal tears were included in this study, including 4 males and 3 females with a mean age of 37.85±7.70 years (range, 27-50 years). The AML, which extends outward and upward and is anterior to the ACL, begins at the AHMM and ends anterior to the femoral attachment of the ACL. The histological staining showed that the AML was a bundle of collagen fibers, whereas the ACL was a bundle of dense fibrous collagen. The AML could be clearly identified in the proton-weighted image of sagittal MRI preoperatively and showed a low signaling similar to the signal intensity of the ACL. AML was easily identified on sagittal MRI but not on axial and coronal MRI. In three patients who underwent bilateral MRI, the AML structure was found in both knees.Conclusion:The incidence of rare anatomic variation between the AHMM and the lateral condyle of the femur is 0.1%, usually occurring in both knees simultaneously. In cases with this variation, there is no bony attachment in the AHMM connected to the ACL via the AML. After transection of the AML, the annular fibrous structure and mechanical properties of the meniscus are damaged, as consequently the AML should be carefully protected in clinical practice.

Objective: To investigate thyroid hormone concentration and associated factors among pubertal girls in Minhang District of Shanghai. Methods: From January to March 2019, a stratified sampling method was used to select junior high schools from the east, south, north, and middle areas in Minhang district. A total of 386 girls of grade 6 in selected schools were included in the study. Physical examination was conducted, and their urine and blood samples were collected to determine urinary iodine concentration (UIC) and thyroid function. Puberty Development Self-rating Scale (PDS) was used to define the pubertal stage. Logistic regression models were conducted to analyze the associations between pubertal stage and thyroid function. Results: The median urinary iodine concentration was 163.57(106.57, 232.96) μg/L. The geometric mean values of TSH, TT3, FT3 and FT4 were 0.29 mU/L, 0.26 nmol/L, 0.68 pmol/L and 1.18 pmol/L.The mean value of TT4 was 91.64 nmol / L. The abnormal rates of TGAb and TPOAb were 6.22% and 4.15%. The rate of abnormal TGAb combined with abnormal TPOAb was 3.68%. Girls in puberty and post-puberty had the lower level of TT4 (OR=0.47,0.43) as compared with girls in pre-puberty stage. Obese girls had higher level of TT3(OR=9.08, 95%CI=1.52-54.07). With the increase of exercise time(0.5-1, >1 h/d), FT4 level was increased (OR=2.45, 2.19). TSH levels were significantly higher in girls with higher TGAb and TPOAb. Girls had higher TT4 or FT4 levels if their TGAb levels were higher and TPOAb levels were normal. Conclusion There is an association between pubertal stage, obesity, exercise and thyroid function in school-aged girls during puberty in iodine sufficient areas. TSH, FT4 and TT4 levels are correlated with TGAb and TPOAb levels.

To prepare RGD peptide modified perfluorohexane ( PFH ) polymer nanoparticles RGD‐PFH‐NPs and investigate its basic characteristics ,targeting ability and combine with low‐intensity focused ultrasound ( LIFU ) for ultrasonic imaging in vivo and vitro . Methods Targeted nanoparticles RGD‐PFH‐NPs were prepared by double emulsifying method and carbodiimide method . T heir morphology and distribution were observed . T he particle size ,zeta potential and connection probability were measured . T he phase‐changed properties and the LIFU‐induced imaging ability in contrast‐enhanced ultrasound mode of RGD‐PFH‐NPs were investigated in vivo and vitro . T he tagetability of nanoparticles to human gastric cancer cell line M GC803 and tumor‐bearing nude mouse were observed through targeting group and non‐targeting group . Results T he prepared sample was milky w hite suspension liquid . T he RGD‐PFH‐NPs were spherical uniform size ,good dispersion w hen observed through the optical microscope and transmission electron microscopy . T he particle size was ( 259 .3 ± 42 .6) nm and the Zeta potential was ( －17 .6+5 .4) mV . T he connection probability of RGD peptide was 89 .13% . With 70℃ water bath and LIFU stimulation RGD‐PFH‐NPs can remarkably change phase and show good imaging performance in both conventional ultrasound and contrast‐enhanced ultrasound mode in vivo and vitro . The connection probability to M GC803 cells in targeting group ( RGD‐PFH‐NPs ) and the non‐targeting group( PFH‐NPs) were 82 .59% and 2 .96% . T he accumulation of nanoparticles in the RGD‐PFH‐NPs group in tumor tissues was significantly higher than that in the non‐targeted PFH‐NPs group( P) . Conclusions The constructed nanoparticles RGD‐PFH‐NPs ,providing contrast‐enhanced ultrasonic imaging and excellent targeting ability to human gastric cancer cells M GC803 and gastric cancer tissue ,is expected to become a new type of gastric cancer targeted ultrasound contrast agent .

Objective To prepare RGD peptide modified perfluorohexane ( PFH ) polymer nanoparticles RGD-PFH-NPs and investigate its basic characteristics ,targeting ability and combine with low-intensity focused ultrasound ( LIFU ) for ultrasonic imaging in vivo and vitro . Methods Targeted nanoparticles RGD-PFH-NPs were prepared by double emulsifying method and carbodiimide method . Their morphology and distribution were observed . The particle size ,zeta potential and connection probability were measured . The phase-changed properties and the LIFU-induced imaging ability in contrast-enhanced ultrasound mode of RGD-PFH-NPs were investigated in vivo and vitro . The tagetability of nanoparticles to human gastric cancer cell line MGC803 and tumor-bearing nude mouse were observed through targeting group and non-targeting group . Results The prepared sample was milky white suspension liquid . The RGD-PFH-NPs were spherical uniform size ,good dispersion when observed through the optical microscope and transmission electron microscopy . The particle size was ( 259 .3 ± 42 .6) nm and the Zeta potential was ( -17 .6+5 .4) mV . The connection probability of RGD peptide was 89 .13％ . With 70℃ water bath and LIFU stimulation RGD-PFH-NPs can remarkably change phase and show good imaging performance in both conventional ultrasound and contrast-enhanced ultrasound mode in vivo and vitro . The connection probability to MGC803 cells in targeting group ( RGD-PFH-NPs ) and the non-targeting group( PFH-NPs)were 82 .59％ and 2 .96％ . The accumulation of nanoparticles in the RGD-PFH-NPs group in tumor tissues was significantly higher than that in the non-targeted PFH-NPs group( P) . Conclusions The constructed nanoparticles RGD-PFH-NPs ,providing contrast-enhanced ultrasonic imaging and excellent targeting ability to human gastric cancer cells MGC803 and gastric cancer tissue ,is expected to become a new type of gastric cancer targeted ultrasound contrast agent .

Sepsis remains the leading cause of death in intensive care unit.The pathogenesis of sepsis is extremely complex.Immune dysfunction plays an important role in the occurrence and development of sepsis.Many mechanisms are responsible for sepsis induced immune-suppression,including apoptotic depletion of immune cells,increased T regulatory and myeloid-derived suppressor cells,and cellular exhaustion.The article provided a brief review on the advance of immunologic mechanisms underlying sepsis.

Objective To explore the advantages and disadvantages of ultrasound guided puncture microwave ablation and traditional surgical treatment of nodular goiter.Methods From January 2014 to June 2015,102 cases of nodular goiter who were treated in the Traditional Chinese Medicine Hospital of Gaozhou Affiliated to Guangzhou University of Traditional Chinese Medicine were randomly divided into two groups,51 cases in each group.Respectively by ultrasound guided puncture nodules of thyroid swollen microwave ablation (microwave ablation group) and traditional operation type removed most of the thyroid nodules (traditional surgery group) in the treatment of containing.The amount of bleeding,operation time,hospital stay,medical cost,clinical efficacy,postoperative complications and the degree of pain,and thyroid function were compared between the two groups.Results The amount of bleeding,operation time and length of hospital stay in the microwave ablation group were better than those in the traditional operation group((2.02±0.79) ml vs.(28.24±18.49) ml,(34.20 ±9.60) min vs.(75.59±25.41) min,(3.55± 1.05) d vs.(10.27±2.68) d),the medical cost of the microwave ablation group was higher than that of the traditional operation group((14 341±593) yuan vs.(5 812±970) yuan),the differences were statistically significant (t =-10.12,-10.88,-16.68,53.54;P ＜0.01).There were significant difference in terms of the postoperative pain and complications between the groups (x2=50.86,13.22;P＜0.01).The total absorption rate was 100％ in 18 months after the ablation of the nodule.There was no significant difference about postoperative residual small nodules between the two groups(P ＞0.05).Conclusion Compared with the traditional treatment,the microwave ablation treatment of nodular goiter with less complications,is a new technique of minimally invasive,beauty,safe and feasible,the exact clinical effect,and worthy of popularization and application.

Objective To explore the effect of decoction of four-drug juice plus glutamine on nutritional support in the elderly critically ill patients. Methods One hundred and twenty-four elderly critical ill patients in The First Hospital of Jilin University from May 2010 to May 2012 were randomly divided into treatment group(n = 62)and control group(n = 62). Patients in both two groups were given enteral nutrition(EN)plus parenteral nutrition(PN)after the hemodynamics became stable. In addition,patients in control group were given routine EN + PN,while in treatment group was given decoction o four-drug juice + EN plus glutamine + PN. Prealbumin (PA),serum total protein( TP),transferrin( TF)and serum albumin( ALB)were detected before and after treatment of nutritional support. The informations including recovery of bowel sounds,the occurrence of complications,antibiotic use time and the duration of ICU stay were recorded. Results There were no significant differences between two groups in terms of nutrition indices before treatment(P > 0. 05). After treatment,the contents of pre albumin,transferrin,total serum protein,serum albumin in treatment group were( 145. 24 ± 6. 72)g/ L,(1. 93 ± 0. 98)g/ L,(79. 86 ± 10. 38)g/ L,(54. 91 ± 2. 91)g/ L respectively,better than those in control groups((139. 24 ± 38. 76),(1. 68 ± 0. 33),(74. 73 ± 7. 31),(49. 87 ± 2. 61)g/ L),and the differences were statistically significant( t = 3. 610,2. 929,4. 360,6. 767;P < 0. 05). The incidence of stress ulcer and double infection in treatment group were 42%(26 / 62),37%(23 / 62),significantly lower than the control group(59%(37 / 62),53%(33 / 62)),and the differences were statistically significant( χ2 = 5. 186, 5. 271,P < 0. 05). Antibiotic use time and the duration of ICU stay in treatment group were(8. 82 ± 0. 71)d and(16. 14 ± 3. 01)d,and reaching full eternal nutrition time was(6. 90 ± 1. 01)d,decreased less than that in control group((10. 21 ± 1. 30),(20. 67 ± 2. 29),(13. 91 ± 1. 51)d)and the differences were statistically significant(t = 8. 892,7. 786,3. 609,P < 0. 05). The average recovery time of bowel sounds and first anal exhaust time average in treatment group were(26. 8 ± 3. 6)h,(25. 4 ± 3. 2)h,lower than that in control group ((38. 4 ± 4. 8)h,(37. 6 ± 4. 9)h)and the differences were statistically significant( t = 3. 551,2. 516,P< 0. 05). Conclusion The application of decoction of four-drug juice plus glutamine on nutritional support of the elderly critically ill patients can reduce complications,shorten the duration of ICU,recover the intestinal function as soon as possible. Meanwhile,patients can transit to full eternal nutrition as soon as possible,then the cost of therapy is reduced and rehabilitation is quickly.