How honey bees dip nectar: Dynamic spacing of tongue hairs facilitates to collect nectar of various viscosities.

A honey bee can dip nectar of viscosity across two orders of magnitude, by viscous lapping technique using a segmental tongue covered with erectable hairs. The drinking technique suffers risks of leakage occurring between tongue hairs, and the amount of leakage is related to hair spacing as well as nectar viscosity. When lapping, tongue segments are elongated, which enlarges the hair spacing in longitudinal direction. Experimental observations show that the hair spacing of tongue increases with respect to sucrose solution concentration until it reaches the maximum extension when sucrose solution concentration is above 35%. Considering leakage occurring in the hairy tongue, we hypothesize that the dynamical extension of hair spacing may help honey bees minimize the effects of leakage to reach maximal nectar intake rate. A mathematical model is developed for determining the optimal hair spacing that can meet the demands of both augmenting the nectar intake rate and reducing the risk of leakage. Theoretical prediction and experimental measurements demonstrate honey bees are able to adjust the tongue to meet the optimal hair spacing when dipping nectar of concentration more dilute than 35% and maintain a maximum extension to improve the nectar intake rate when concentration is greater than 35%. We then give the prediction of concentration preferences of three bee species, and discuss effects of dipping frequency and gravity on the leakiness between tongue hairs. This work may not only gain insights into adaptive feeding strategy in insects, but inspire the design of adaptive microfluidic transport devices with dynamic brushy surfaces.

Efficacy and safety of oral tranexamic acid in total knee arthroplasty: A systematic review and meta-analysis.

BACKGROUND: Tranexamic acid (TXA) is an antifibrinolytic drug widely used as a blood-sparing technique in total knee arthroplasty (TKA), and it is usually administrated by intravenous or intraarticular injection. Recently, the oral form of TXA has been applied in TKA patients. However, there is no final consensus regarding the effectiveness and safety of oral TXA. The purpose of this systematic review and meta-analysis of randomized controlled trials (RCTs) was to evaluate the efficacy and safety of oral TXA versus control for blood loss after TKA. METHODS: We searched PubMed, Embase, Medline, Web of Science, and Cochrane Library databases for relevant studies through August 2017. The mean difference (MD) of total blood loss, hemoglobin (Hb) drop, hematocrit (Hct), drain output, and risk difference (RD) of transfusion rate and thromboembolic complications in the TXA and control groups were pooled throughout the study. The outcomes were pooled by Stata 12.0. RESULTS: A total of 5 RCTs (608 patients) were included in this study. All the included studies were randomized and the quality of included studies was relatively high. The pooled results indicated that the oral TXA group had significantly less Hb drop (standardized mean difference [SMD], -0.936; 95% confidence intervals [CI], -1.118,-0.754), Hct drop (SMD, -0.693; 95% CI, -1.113, -0.274), and drain output (SMD, -0.793; 95% CI, -0.959, -0.628) than the control group. No statistically significant differences were found in transfusion rate and the incidence of thromboembolic complications between the 2 groups. Total blood loss could not be evaluated for the insufficient date. CONCLUSIONS: Our meta-analysis suggested that the administration of oral TXA provided significantly better results with respect to Hb drop, Hct drop, and drain output without increasing the transfusion rate and the risk of thromboembolic complications after TKA. Nevertheless, our current study with some limitations such as the small sample size only provided limited quality of evidence, confirmation from further meta-analysis with large-scale, well-designed RCTs is required.

Radiological analysis of cystic lesion in osteonecrosis of the femoral head.

PURPOSE: Cystic lesions are a common complication in osteonecrosis of the femoral head (ONFH). This study will discuss the cause of cystic lesion formation and the feature of cystic lesion distribution in ONFH. According to the feature of cystic lesion in ONFH, we will discuss the possible mechanisms of cystic lesions and their  influence on collapse of the femoral head. MATERIALS AND METHODS: We retrospectively gathered 102 ONFH patients (168 hips) from November in 2015 to August in 2016 on China-Japan Friendship Hospital. Three categories of patients' medical information were collected: demographic characteristics, bone cystic lesion location, and pathological finding on CT and MRI imaging (microfracture, collapse, crescent sign). On mid-coronal and mid-axial CT section, the femoral head was divided into four quadrants for locating the cystic lesion. And we classified the location relationship of cystic lesion and sclerosis rim as G1 type, G2 type, and G3 type on coronal CT section. RESULTS: A significant difference was found between ONFH group with cystic lesion and ONFH group without cystic lesion in terms of microfracture (P < 0.001), collapse (P < 0.001), and crescent sign (P < 0.001). Forty-four cystic lesions (70%) are located in anterior hip area and 19 cystic lesions (30%) are located in posterior hip area. There were 14, 24, and seven cystic lesions (31, 53, 16%) locating in lateral, central, and medial pillars of the femoral head. G2 type was the most common pattern of location relationship between cystic lesion and sclerosis rim. CONCLUSION: Cystic lesions are often found near sclerosis rim in ONFH. The femoral head with osteonecrosis complicating by cystic lesions is more likely to accompany microfracture, collapse, and crescent sign which indicate structural instability in the femoral head. Cystic lesion in ONFH plays an important role in aggravating the progression of femoral head collapse. The peak stress from sclerosis rim may be a main factor inducing the formation of cystic lesion in ONFH via an OA-like mechanism.

Hyperuricemia has an adverse impact on the prognosis of patients with osteosarcoma.

Patients with osteosarcoma have poor prognosis and are often at high risk of death. Identification of prognostic biomarkers for osteosarcoma may aid in improving the survival. Hyperuricemia had been suggested as a poor prognostic factor of several cancers, but the prognostic role of hyperuricemia in osteosarcoma patients had not been assessed. In the present study, we investigated the prognostic role of hyperuricemia at baseline on the overall survival of patients with osteosarcoma. Sixty osteosarcoma patients with hyperuricemia were matched (1:2) to 120 osteosarcoma patients without hyperuricemia with similar age and gender. Data from those patients with osteosarcoma were evaluated retrospectively. The role of hyperuricemia on overall survival was firstly analyzed using the Kaplan-Meier method. Univariate and multivariate Cox regression models were also used to further evaluate the prognostic significance of hyperuricemia. None of the clinicopathological parameters except distant metastasis was associated with hyperuricemia. Kaplan-Meier method showed that patients with hyperuricemia had shorter overall survival compared with those with normouricemia (P < 0.0001, log-rank test). In univariate analysis, hyperuricemia was associated with poorer overall survival in osteosarcoma patients (HR = 2.71, 95 % CI 1.75-4.20; P < 0.0001). In the multivariate analysis, after adjusting for age, gender, serum alkaline phosphatase, stage, tumor size, and metastasis, hyperuricemia was independently associated with poorer overall survival in osteosarcoma patients (HR = 2.28, 95 % CI 1.41-3.69; P = 0.001). In conclusion, hyperuricemia at baseline is associated with poorer overall survival in osteosarcoma patients, and it has an adverse impact on the prognosis of osteosarcoma patients.

In vivo study of immunogenicity and kinetic characteristics of a quantum dot-labelled baculovirus.

Nanomaterials conjugated with biomacromolecules, including viruses, have great potential for in vivo applications. Therefore, it is important to evaluate the safety of nanoparticle-conjugated macromolecule biomaterials (Nano-mbio). Although a number of studies have assessed the risks of nanoparticles and macromolecule biomaterials in living bodies, only a few of them investigated Nano-mbios. Here we evaluated the in vivo safety profile of a quantum dot-conjugated baculovirus (Bq), a promising new Nano-mbio, in mice. Each animal was injected twice intraperitoneally with 50 µg virus protein labelled with around 3*10(-5)nmol conjugated qds. Control animals were injected with PBS, quantum dots, baculovirus, or a mixture of quantum dots and baculovirus. Blood, tissues and body weight were analysed at a series of time points following both the first and the second injections. It turned out that the appearance and behaviour of the mice injected with Bq were similar to those injected with baculovirus alone. However, combination of baculovirus and quantum dot (conjugated or simply mixed) significantly induced stronger adaptive immune responses, and lead to a faster accumulation and longer existence of Cd in the kidneys. Thus, despite the fact that both quantum dot and baculovirus have been claimed to be safe in vivo, applications of Bq in vivo should be cautious. To our knowledge, this is the first study examining the interaction between a nanoparticle-conjugated virus and a living body from a safety perspective, providing a basis for in vivo application of other Nano-mbios.