Host feces, olfactory beacon guiding aggregation of intestinal parasites Gasterophilus pecorum (Diptera: Gasterophilidae).

The aim of this study was to identify the aggregation sites and transmission characteristics of Gasterophilus pecorum, the dominant pathogen of endangered equines in desert steppe. Therefore, we tested with a four-arm olfactometer the olfactory response of the G. pecorum adults to the odors that have a great impact on their life cycle, and also investigated the occurrence sites of the adults in the area where the Przewalski's horse (Equus przewalskii) roam frequently during the peak period of G. pecorum infection. The results of four-directional olfactory test showed that the fresh horse feces had a stronger attraction rate on both male (50.4%) and female flies (38.2%). Stipa caucasica, the only oviposition plant where G. pecorum lay eggs, had a better attraction effect on females than that on males. And the attraction rates of S. caucasica to G. pecorum females in the early growth stage (Stipa I) and mid-growth stage (Stipa II) were 32.8% and 36.8%, respectively. In addition, the two-directional olfactory test showed that the attraction rate of males to fresh horse feces (68.90%) was higher than that to Stipa II (31.10%), and females also showed similar olfactory responses. Moreover, in our field investigation, 68.29% of G. pecorum adults were collected from around the horse feces. The results of laboratory test and field investigation implied that the location mechanism of G. pecorum aggregation for mating is related to the orientation of horse feces. The horse feces and the vicinity are the key contamination areas of G. pecorum, and it is also the areas where horses are seriously infected with G. pecorum. Those fresh feces, which gather abundant information about the host, naturally had the greatest chance of contacting with the host; G. pecorum adults create the opportunity to enter directly into the host's mouth and infect the host by laying eggs on S. caucasica, which is the most favorite plant of the host in this area. These characteristics are one of the main reasons why G. pecorum has become the dominant species under the condition of sparse vegetation in desert steppe.

Functionalized graphene oxide-based thermosensitive hydrogel for magnetic hyperthermia therapy on tumors.

A novel locally injectable, biodegradable, and thermo-sensitive hydrogel made from chitosan and ß-glycerophosphate salt was prepared. It incorporated polyethylenimine (PEI)-modified super-paramagnetic graphene oxide (GO/IONP/PEI) as a form of minimally invasive treatment of cancer lesions by magnetically induced local hyperthermia. Doxorubicin (DOX) was mixed into the hydrogel which was pre-loaded on GO/IONP/PEI to create a drug delivery system DOX-GO/IONP/PEI-gel. In addition to the evaluation of in vitro and in vivo antitumor activities, the physicochemical properties, magnetic properties and DOX release profile of the DOX-GO/IONP/PEI-gel were determined. The aqueous solution of the hydrogel showed a sol-gel transition behavior depending on temperature changes. Magnetization loops indicated the super-paramagnetic properties of GO/IONP/PEI. Compared with free DOX, DOX-GO/IONP/PEI could efficiently pass through cell membranes, leading to more apoptosis and demonstrating higher antitumor efficacy on MCF-7 cells in vitro. Furthermore, DOX-GO/IONP/PEI-gel intratumorally injected (i.t.) showed high antitumor efficacy on tumor-bearing mice in vivo, with no obvious toxicity. The antitumor efficacy was higher when combined with an alternating magnetic field (AMF), showing that DOX-GO/IONP/PEI-gel under AMF has great potential for cancer magnetic hyperthermia therapy.

The impact of pegylated recombinant human growth hormone replacement therapy on glucose and lipid metabolism in children with growth hormone deficiency.

BACKGROUND: This study aimed to investigate the impact of pegylated recombinant human growth hormone (PEG-rhGH) replacement therapy on glucose and lipid metabolism in children with growth hormone deficiency (GHD). METHODS: A total of 17 children with a growth hormone deficiency were treated with PEG-rhGH (trade name Juyi' Erchun) via subcutaneous injection once a week before sleep for 3 months. The doses given were 0.2 and 0.15 mg/(kg·week). The injection sites included the upper arm, the front of the thigh, and the periumbilical area of the abdominal wall. Follow-ups were conducted every 3 months after the treatment to detect the metabolic indexes of the children's blood glucose and blood lipids. Growth and development indexes, thyroid function, and other indexes were also detected regularly. The glucose and lipid metabolism indexes of each child, including fasting blood glucose, glycosylated hemoglobin, fasting insulin, total cholesterol, triglycerides, high-density lipoprotein (HDL), and low-density lipoprotein (LDL), were measured before the treatment and every three months after the treatment. The total detection time was 3-30 months. RESULTS: No significant differences in fasting blood glucose, glycosylated hemoglobin, fasting insulin, total cholesterol, triglycerides, HDL, and LDL were detected after the treatment when compared with measurements taken before the treatment (P>0.05). CONCLUSIONS: PEG-rhGH replacement therapy may have no significant impact on glucose and lipid metabolism in children with GHD. However, this conclusion needs to be verified through studies with larger samples and long-term follow-up periods.

Mineral oil-, glycerol-, and Vaseline-coated plates as matrix-assisted laser desorption/ionization sample supports for high-throughput peptide analysis.

A novel protocol for rapid and high-quality sample preparation prior to matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been developed by coating bare stainless steel plates with one of three adhesives: mineral oil, glycerol, or Vaseline. The advantages of these three adhesive coats are that they take little time to both prepare and wipe away, hold the matrices to prevent them from flying from the support, reduce the background matrix, and affect neither the resolution of the peptide peaks nor the accuracy of their determined molecular masses. Consequently, the signal intensity, detection limit, and tolerance of the analytes to contaminants on the three adhesive-coated plates are improved. In the two strategies of on-plate desalting and concentration of the peptide mixture, all three adhesives reduced the loss of peptides, especially in the case of larger molecular mass peptides. The microscope and stereomicroscope images of the deposited droplets showed that after dropping onto the adhesive coats, the droplets formed a reduced spot size, were more homogeneous, and showed sticky crystallization. Therefore, this is an easy-to-use, reproducible, highly sensitive, tolerant (to salts), and high-throughput method of peptide sample preparation for MALDI-TOF MS analysis.

Functionalized graphene oxide-based thermosensitive hydrogel for near-infrared chemo-photothermal therapy on tumor.

PURPOSE: A functionalized graphene oxide-based thermosensitive hydrogel loaded with docetaxel for intratumoral delivery was designed to enhance therapeutic efficacy and alleviate system toxicity. METHODS: First, graphene oxide was functionalized with chitosan to acquire high stability in physiological solutions. And then docetaxel-graphene oxide/chitosan gel was formed by mixed docetaxel-graphene oxide/chitosan suspension with hydrogel which was made from Poloxamer 407 and Poloxamer 188. Cellular uptake, antitumor effect in vitro and in vivo, cell apoptosis, and biodistribution of docetaxel-graphene oxide/chitosan gel were investigated, compared with the docetaxel solution. RESULTS: Graphene oxide/chitosan was stable in physiological solution, and docetaxel released much slower from docetaxel-graphene oxide/chitosan gel with a pH-responsive feature. Compared with free docetaxel, docetaxel-graphene oxide/chitosan could afford higher antitumor efficacy in Michigan Cancer Foundation-7 (MCF-7) cells in vitro. Furthermore, docetaxel-grapheme oxide/chitosan gel which was injected within tumor could afford higher concentration and longer resident time in tumor tissues of mice in vivo, without obvious toxic effects to normal organs. Meanwhile, the combination of near-infrared laser irradiation at 808 nm significantly enhanced tumor inhibition in vitro and in vivo. CONCLUSIONS: Docetaxel-graphene oxide/chitosan gel in combination with 808 nm near-infrared laser irradiation had great potential for cancer chemo-photothermal therapy.

Investigation on Single-walled Carbon Nanotubes-Liposomes Conjugate to Treatment Tumor with Dual-mechanism.

Single-walled carbon nanotubes (SWNT) have been widely explored as carriers for drug delivery because of their large surface area, high near-infrared absorption coefficient and facile transport through cellular membranes. In this study, Lysine (Lys) modified SWNT-liposomes conjugate loaded with doxorubicin (DOX) was designed to enhance the targeted drug delivery and antitumor effect. The conjugate (DOX-Lys/SWNT-Lip) was prepared with pH gradient methods, and the mean particle size and drug entrapment efficiency were 223±5.9 nm and 85.9 %, respectively. In vitro drug release study showed that DOX released much slowly from DOX-Lys/SWNT-Lip than from DOX solution, but faster than that of DOX-Lys/SWNT. DOX-Lys/SWNT-Lip could efficiently cross the cell membrane and afford higher anti-tumor efficacy on MCF-7 cells in vitro. For in vivo experiment, normal saline (N.S.), and DOX or DOX-Lys/SWNTLip were given to the S180 tumor bearing mice by i.v. administration, and followed by exposing the tumor site to nearinfrared laser (NIR) irradiation at 808 nm for 2 min. The relative tumor volumes in DOX-Lys/SWNT-Lip group and DOX group were obviously smaller than those of N.S. group. When combined with NIR laser irradiation, the suppression on tumor growth was much stronger. In conclusion, this study may provide potentially viable clinical strategies for tumor treatment with chemotherapy and photothermal therapy dual-mechanism.

Thermo-sensitive liposomes loaded with doxorubicin and lysine modified single-walled carbon nanotubes as tumor-targeting drug delivery system.

This report focuses on the thermo-sensitive liposomes loaded with doxorubicin and lysine-modified single-walled carbon nanotube drug delivery system, which was designed to enhance the anti-tumor effect and reduce the side effects of doxorubicin. Doxorubicin-lysine/single-walled carbon nanotube-thermo-sensitive liposomes was prepared by reverse-phase evaporation method, the mean particle size was 232.0 ± 5.6 nm, and drug entrapment efficiency was 86.5 ± 3.7%. The drug release test showed that doxorubicin released more quickly at 42℃ than at 37℃. Compared with free doxorubicin, doxorubicin-lysine/single-walled carbon nanotube-thermo-sensitive liposomes could efficiently cross the cell membranes and afford higher anti-tumor efficacy on the human hepatic carcinoma cell line (SMMC-7721) cells in vitro. For in vivo experiments, the relative tumor volumes of the sarcomaia 180-bearing mice in thermo-sensitive liposomes group and doxorubicin group were significantly smaller than those of N.S. group. Meanwhile, the combination of near-infrared laser irradiation at 808 nm significantly enhanced the tumor growth inhibition both on SMMC-7721 cells and the sarcomaia 180-bearing mice. The quality of life such as body weight, mental state, food and water intake of sarcomaia 180 tumor-bearing mice treated with doxorubicin-lysine/single-walled carbon nanotube-thermo-sensitive liposomes were much higher than those treated with doxorubicin. In conclusion, doxorubicin-lysine/single-walled carbon nanotube-thermo-sensitive liposomes combined with near-infrared laser irradiation at 808 nm may potentially provide viable clinical strategies for targeting delivery of anti-cancer drugs.

[Preliminary clinical application of cancellous granule-type calcium phosphate cement].

OBJECTIVE: To investigate the clinical efficacy of the cancellous granule-type calcium phosphate cement in repair bone defect. METHODS: Between July 2008 and July 2009, 35 patients (42 limbs) with fractures, nonunion, and benign bone tumor were treated with cancellous granule-type calcium phosphate cement. There were 32 males and 3 females, with an age range from 9 to 73 years (median, 41 years), including 24 limb fractures (19 cases), 4 osteotomy for deformity of ulna and radius (2 cases), 2 femur intertrochanteric bony cysts (2 cases), 3 enchondroma (3 cases), 5 bone defect at donor ilium (5 cases), 3 nonunion (3 cases), and 1 lumbar spinal stenosis (1 case). The size of bone defect was 1-5 cm. Bone defect was repaired with cancellous granule-type calcium phosphate cement (1-5 g). RESULTS: All cases were followed up 8-23 months (13.7 months on average). Thirty-nine incisions (32 cases) healed by first intention and the suture was removed after 10-14 days. Incision dehiscence occurred in 2 cases, and wounds healed after second debridement and removal of artificial bone. Exudation of incision occurred in 1 case, and wound healed after symptomatic treatment. No local red swelling, higher temperature, maculopapular, and ulceration of skin occurred at implantation site. X-ray films showed that bone graft fusion was achieved and bone defect was radically repaired at 6 months after operation and artificial bone was absorbed completely at 12 months. CONCLUSION: Cancellous granule-type calcium phosphate cement can be used as a new graft bone material, which is suitable for defect filling after traumatic fracture, benign bone tumors, and iliac bone donor.

[Bone inductive effects of rhBMP-2 loaded porous CPC implants on spine fusion in rabbits].

OBJECTIVE: To investigate the effect of rhBMP-2 combined with porous CPC on spine fusion in rabbits. METHODS: rhBMP-2 (1 mg) was loaded with 1 g CPC and 6.0 cm x 2.0 cm x 0.5 cm absorbable gelatin sponge (AGS), respectively, and thereafter frozen to prepare the biomaterial of rhBMP-2/CPC and rhBMP-2/AGS. Forty-five 24-week-old New Zealand rabbits (weight 2.5-3.5 kg) were randomly divided into 3 groups: group A (n=17), group B (n=11) and group C (n=17). With the exposure and removal of L5,6 transverse process's posterior bone cortex in all the rabbits, the corresponding cancellous bones were exposed and the posterior bilateral intertransverse bone grafting of L5,6 were performed on the three groups, then the rhBMP-2/CPC, rhBMP-2/AGS and CPC was implanted into the rabbits of group A, B and C, respectively. Gross observation, histology assay and image examination were conducted 4, 8 and 24 weeks after operation. RESULTS: Decalcified hard tissue section demonstrated obvious callus connections in group A, small pieces of callus in group B, and fibrous connection and few cartilage in group C at 4 and 8 weeks after operation. By Kacena measurement standard, the score of group A, B and C at 4 weeks after operation was (7.30 +/- 0.76), (3.68 +/- 1.60) and (1.75 +/- 0.54) points, respectively, and their score at 8 weeks after operation were (8.32 +/- 1.11), (3.75 +/- 1.23) and (1.47 +/- 0.23) points, respectively, indicating there were significant differences between group A and group B as well as between group A and group C at different time points (P < 0.05). Undecalcified hard tissue section demonstrated that there was cancellous bone-like tissue regeneration in group A, and fiber connection around the implants and little ossification in group C at 4 and 8 weeks after operation. By three dimensions reconstructed CT, group A, B and C scored (2.50 +/- 0.57), (1.00 +/- 0.00) and (1.00 +/- 0.00) points respectively, indicating there was a significant difference between group C and groups A and B as well as between group A and group B (P < 0.05). CONCLUSION: As a carrier of rhBMP-2, the CPC is capable of promoting spine bone fusion in rabbits and is a new type of artificial bone repair material.