METHODS: Rosetting rates of clinical isolates pre- and post- brief (one hour) exposure to artesunate (AS, an ART derivative) were evaluated. The effects of AS-mediated rosetting on the post-AS-exposed parasite's replication and survival, as well as the extent of protection by AS-mediated rosetting on different parasite stages were investigated. The rosetting ligands, mechanisms, and gene mutations involved were studied.
FINDINGS: Brief AS exposure stimulated rosetting, with AS-resistant isolates forming more rosettes in a more rapid manner. AS-mediated rosetting enabled infected erythrocytes (IRBC) to withstand AS exposure for several hours and protected the IRBC from phagocytosis. When their rosetting ability was blocked experimentally, the post-AS exposure survival advantage by the AS-resistant parasites was abrogated. Deletions in two genes coding for PfEMP1 exon 2 (PF3D7_0200300 and PF3D7_0223300) were found to be associated with AS-mediated rosetting, and these mutations were significantly selected through time in the parasite population under study, along with the K13 mutations, a molecular marker of ART-resistance.
INTERPRETATION: Rapid ART parasite clearance is driven by the direct oxidative damages on IRBC by ART and the phagocytic destruction of the damaged IRBC. Rosetting serves as a rapid 'buying time' strategy that allows more parasites to complete schizont maturation, reinvasion and subsequent development into the intrinsically less ART-susceptible ring stage.
FUNDING: A*STAR, NMRC-OF-YIRG, HRC e-ASIA, Wellcome.
MATERIALS AND METHODS: Medical records of 407 cervical cancer patients between 1st January 2002 to 31st December 2012 were reviewed. Some 32 cases with positive PALN were identified to have received definitive extended field radiotherapy with or without chemotherapy. Treatment outcomes, clinicopathological factors affecting survival and radiotherapy related acute and late effects were analyzed.
RESULTS: Totals of 13 and 19 patients underwent EFRT and CCEFRT respectively during the period of review. The median follow-up was 70 months. The 5-year overall survival (OS) was 40% for patients who underwent CCEFRT as compared to 18% for patients who had EFRT alone, with median survival sof 29 months and 13 months, respectively. The 5-years progression free survival (PFS) for patients who underwent CCEFRT was 32% and 18% for those who had EFRT. Median PFS were 18 months and 12 months, respectively. Overall treatment time (OTT) less than 8 weeks reduced risk of death by 81% (HR=0.19). Acute side effects were documented in 69.7% and 89.5% of patients who underwent EFRT and CCEFRT, respectively. Four patients (12.5%) developed radiotherapy late toxicity and there was no treatment-related death observed.
CONCLUSIONS: CCEFRT is associated with higher 5-years OS and median OS compared to EFRT and with tolerable level of acute and late toxicities in selected patients with cervical cancer and PALN metastasis.
OBJECTIVE: We studied the incidence of deep-vein thrombosis (DVT) in Asian patients undergoing major orthopedic surgery of the lower limbs.
PATIENTS/METHODS: We performed a prospective epidemiological study in 19 centers across Asia (China, Indonesia, South Korea, Malaysia, Philippines, Taiwan, and Thailand) in patients undergoing elective total hip replacement (THR), total knee replacement (TKR) or hip fracture surgery (HFS) without pharmacological thromboprophylaxis. The primary endpoint was the rate of DVT of the lower limbs documented objectively with bilateral ascending venography performed 6-10 days after surgery using a standardized technique and evaluated by a central adjudication committee unaware of local interpretation.
RESULTS: Overall, of 837 Asian patients screened for this survey, 407 (48.6%, aged 20-99 years) undergoing THR (n = 175), TKR (n = 136) or HFS (n = 96) were recruited in 19 centers. DVT was diagnosed in 121 of 295 evaluable patients [41.0%, (95% confidence interval (CI): 35.4-46.7)]. Proximal DVT was found in 30 patients [10.2% (7.0-14.2)]. Total DVT and proximal DVT rates were highest in TKR patients (58.1% and 17.1%, respectively), followed by HFS patients (42.0% and 7.2%, respectively), then THR patients (25.6% and 5.8%, respectively). DVT was more frequent in female patients aged at least 65 years. Pulmonary embolism was clinically suspected in 10 of 407 patients (2.5%) and objectively confirmed in two (0.5%).
CONCLUSIONS: The rate of venographic thrombosis in the absence of thromboprophylaxis after major joint surgery in Asian patients is similar to that previously reported in patients in Western countries.