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Due to the extremely low C/N ratio, high concentration of ammonia nitrogen and refractory organic matter of mature landfill leachate (MLL), appropriate processes should be selected to effectively remove nitrogen and reduce disposal costs. Partial nitritation (PN) and anaerobic ammonia oxidation (AMX) have been used as the main nitrogen removal processes for MLL, and the sludge granulation in PN and AMX processes could contribute to high biological activity, good sedimentation performance, and stable resistance to toxicity. In this study, the O

Bioconversion of chitin-containing waste to N-acetyl-d-glucosamine (GlcNAc) is of economic interest. Highly efficient chitinases are thus desirable. Bacillus subtilis is a well-known microorganism for industrial protein production and biocontrol, however its chitinolytic enzyme has not been studied in detail. In this study, BsChi from B. subtilis was recombinantly expressed in Escherichia coli and characterized as a potent chitinase for degrading crystalline chitin substrates such as α-chitin, β-chitin and crab shells. BsChi was found to outperform the well-known SmChiA from Serratia marcescens and the commercial chitinase preparation from Streptomyces griseus in degrading crude crab shell which was pretreated by mechanical grinding and protease. In combination with OfHex1, a β-N-acetyl-d-hexosaminidase from the insect Ostrinia furnacalis, BsChi could produce 1.63 g of GlcNAc with 95% purity from 10 g of pretreated crab shells with a yield of 60%.

Peripheral vascular disease (PVD) is a prevalent vascular disease that affect a large number of patients. The establishment of optimal treatments to mitigate the intimal hyperplasia (IH)-induced restenosis would help relieve the health burden of the PVD. Ribonucleotide reductase M2 (RRM2) is critical to cellular migration and proliferation. We have previously demonstrated that suppression of RRM2 expression could substantially inhibit hepatocellular carcinoma cell proliferation and migration. We hereby developed RRM2 small interfering RNA (siRNA)-loaded cell penetrating peptides-conjugated liposome-polycation-DNA complex (LPD) (RRM2-CLPD), aiming to inhibit the migration and proliferation of vascular smooth muscle cells (VSMCs) crucial for IH. RRM2-CLPD is of a small size (∼150 nm) and high siRNA encapsulation efficiency (∼90%). Further, we demonstrated that RRM2-CLPD could significantly inhibited RRM2 gene and protein expression by ∼80%. Notably, RRM2-CLPD was able to effectively bind to VSMCs, resulting in significant cellular proliferation and migration inhibition. Taken together, RRM2-CLPD represent a very promising treatment for IH.

To evaluate the incidence of postoperative venous thromboembolism after gynecologic surgery by mode of incision.We conducted a retrospective cohort study of all patients who underwent gynecologic surgery from May 2006 to June 2015 at two tertiary care academic hospitals in Massachusetts. Billing and diagnosis codes were used to identify surgeries and cases of venous thromboembolism.A total of 43,751 surgical encounters among 37,485 individual patients were noted during the study. The overall incidence of venous thromboembolism is 0.2% for all gynecologic surgeries, 0.7% for hysterectomy, and 0.2% for myomectomy. Compared with patients undergoing laparotomy, patients who underwent minimally invasive gynecologic surgery were less likely to develop venous thromboembolism (laparoscopy risk ratio 0.22, 95% CI 0.13-0.37; vaginal surgery risk ratio 0.07, 95% CI 0.04-0.12). This effect persisted when data were adjusted for other known venous thromboembolism risk factors such as age, race, cancer, medical comorbidities, use of pharmacologic thromboprophylaxis, admission status, and surgical time.Minimally invasive surgery is associated with a decreased risk of venous thromboembolism in patients undergoing gynecologic surgery, including hysterectomy and myomectomy. Although society guidelines and risk assessment tools do not currently account for mode of surgery when assessing venous thromboembolism risk and recommendations for prevention, there is a small but growing body of evidence in both general and gynecologic surgery literature that surgical approach affects a patient's risk of postoperative venous thromboembolism. Mode of surgery should be considered when assessing venous thromboembolism risk and planning venous thromboembolism prophylaxis for patients undergoing gynecologic surgery.

Objectives: To explore the implications of cervical conization specimens lacking the targeted high-grade squamous intraepithelial lesions (negative cone). Methods: We studied 540 conization procedures: 400 positive cones and 140 negative cones. Clinicopathologic features and 2-year follow-up results were reported. Results: Negative cones comprised 22% of procedures triggered by CIN2 or higher biopsies. Procedures triggered by cytology produced much higher percentages of negative cones (37% high-grade squamous intraepithelial lesion [HSIL], 46% atypical squamous cells—cannot exclude high-grade squamous intraepithelial lesion [ASC-H], and 76% low-grade squamous intraepithelial lesion—cannot exclude high-grade squamous intraepithelial lesion [LSIL-H]). Upon reviewing negative excision-triggering biopsy and cytology, we downgraded 24 (24%) CIN2 biopsies, three (14%) HSIL, five (83%) ASC-H, and 12 (92%) LSIL-H. One-third of our negative cones can be attributed to overdiagnosis either on biopsy or cytology. Patients with negative cones were older and had smaller excisions, negative colposcopic findings, and negative/equivocal high-risk human papillomavirus (HR-HPV). Within 2 years, 35 (25%) women with negative cones experienced ASCUS or LSIL. Only one (0.7%) recurred as CIN3, a significantly lower percentage than women with positive cones (13%). Conclusions: We advocate careful review of all excision-triggering biopsy and cytology, especially in cases of LSIL-H. Patients with negative cones should be surveyed with cytology and HR-HPV testing.