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Introduction: Ecosystem restoration facilitates ecological succession. When a coral reef experiences a disturbance, the community of sessile benthic organisms can follow a successional trajectory that favors the dominance of coral or a change of state to an ecosystem dominated by algae. Objective: To better understand the impact of coral transplants on succession of the sessile benthic community. Methods: To measure and monitor the coral cover (cm2) of Pocillopora spp., and the composition of the associated benthic community, experimental and control coral reef patches were established at the coral restoration site in Golfo Dulce, South Pacific Costa Rica. Thirty Pocillopora spp. colonies were attached to nails on the substrate in an experimental patch. The control coral patch contained nails with non-transplanted colonies. Both treatments were photographed monthly during a period of eight months. Changes in the coverage of coral and other sessile benthic organisms were measured from the images and compared over time between the experimental and control patches. Results: The coral transplants experienced bleaching events in August through September 2019 and January through February 2020. The first bleaching event possibly due to sedimentation, and the second to high temperatures. By the end of the experiment, 83 % of the colonies had survived. The live colonies grew significantly following transplantation; > 67 % of their initial coverage area after eight months. In the experimental patch, the areas of Pocillopora spp., coralline crustose algae (CCA), and cyanobacteria increased while the area of algal turf decreased. The increase in coral coverage and CCA, and decrease in algal turf in the experimental patch could be due to herbivores attracted to transplants. The increase in cyanobacteria in the experimental patch could be the result of higher temperatures and may have been a factor in the death of colonies. Conclusions: The transplantation of Pocillopora spp. colonies in Golfo Dulce changed the early successional trajectory of the sessile benthic community to favor the dominance of coral dominance in the experimental patch. These results may be useful in informing expectations for future restoration efforts.
Introducción: La restauración de ecosistemas facilita la sucesión ecológica. Cuando un arrecife de coral experimenta una perturbación, la comunidad de organismos sésiles bentónicos puede seguir una trayectoria de sucesión que favorezca la dominancia del coral o un cambio de estado a un ecosistema dominado por algas. Objetivo: Comprender mejor el impacto de los trasplantes de coral en la sucesión de la comunidad bentónica sésil. Métodos: Para medir y monitorear la cobertura de coral (cm2) de Pocillopora spp. y la composición de la comunidad bentónica asociada se establecieron parches de arrecifes de coral experimentales y de control en el sitio de restauración de coral en Golfo Dulce, Pacífico Sur de Costa Rica. Treinta colonias de Pocillopora spp., se trasplantaron a los clavos en el sustrato en el parche experimental. El parche de coral de control contenía clavos sin colonias trasplantadas. Ambos tratamientos fueron fotografiados mensualmente durante un periodo de ocho meses. Los cambios en la cobertura de coral y otros organismos bentónicos sésiles se midieron a partir de las imágenes y se compararon a lo largo del tiempo entre los parches experimentales y de control. Resultados: Los trasplantes de coral experimentaron eventos de blanqueamiento de agosto a septiembre de 2019 y de enero a febrero de 2020. El primer evento de blanqueamiento puede haber sido el resultado de la sedimentación y el segundo puede deberse a las altas temperaturas. Al final del experimento, el 83 % de las colonias habían sobrevivido. Las colonias vivas crecieron significativamente después del trasplante; > 67 % de su área de cobertura inicial después de ocho meses. En el parche experimental, las áreas de Pocillopora spp., algas coralinas costrosas (ACC) y cianobacterias aumentaron mientras que el tapete de algas disminuyó. El aumento en la cobertura de coral y ACC, y la disminución en tapetes de algas en el parche experimental podría deberse a los herbívoros atraídos por los trasplantes. El aumento de cianobacterias en el parche experimental podría ser el resultado de temperaturas más altas y puede haber sido un factor en la muerte de las colonias. Conclusiones: El trasplante de las colonias de Pocillopora spp. en Golfo Dulce cambiaron la trayectoria de sucesión temprana de la comunidad bentónica sésil para favorecer la dominancia del coral en el parche experimental. Estos resultados pueden ser útiles para informar las expectativas de futuros esfuerzos de restauración.
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Heat stroke is a critical and health-threatening disease, triggered by thermal stimulus and progressing rapidly. It can give rise to multiple organ dysfunction syndrome (MODS), resulting in a high mortality rate. Nearly 30% of survivors will suffer with different sequelae, for instance, the neurological sequelae. Currently, the early rapid cooling is the focus of therapy for heat stroke. Therefore, it is imperative to design a cooling module suitable for the treatment of heat stroke in the field and in the hospital to realize the goal of early rapid cooling and the effective targeted temperature management (TTM). The cooling device is composed of a cooling blanket and a cooling cap. The blanket and cap are made by temperature changeable fabric. The cooling blanket comprises a backing layer, a buffer layer, a flexible heat conduction capsule body, a temperature changing component, a fixed part and a temperature sensor. The cooling cap includes a main body and two side ears, in which the main body is worn on the top of the patient's head, and the front is equipped with a flexible display screen, which is convenient for real-time monitoring the temperature of the temperature change component of the cooling blanket. The lateral ear can wrap the patient's ears and neck, and the tympanic membrane thermometer is designed to monitor the tympanic membrane temperature in real time. The tympanic membrane thermometer is also designed at the ear to monitor the tympanic auditory canal temperatures in real time.Continuous dynamic temperature monitoring can guide the duration of cooling treatment and stop cooling in time. The cooling component is portable, easy to operate, real-time temperature monitoring, excellent cooling effect and reusable. It is used for on-site first aid, transportation and continuous cooling for patients with heat stroke in the ward.
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Objective:To investigate the effect of self-made phase-change nanodroplets IR780/FA-Nds-DTX as molecular targeted ultrasound contrast agents for accurate diagnosis and combined targeted therapy of pancreatic cancer.Methods:Pancreatic cancer cell lines were cultured in vitro and 50 tumor bearing nude mouse models were established. The experimental group (IR780/ FA-NdS-DTX) and four control groups[ normal saline, Nds(FITC), FA-Nds (FITC) and IR-780] were divided to verify dual-mode targeted imaging. The imaging using the IVIS Imaging System verified the high-efficiency targeted detection ability and near-infrared fluorescence imaging of IR780/FA-Nds-DTX for tumors in vivo, phase transformation induced by low-intensity focused ultrasound and further contrast-enhanced ultrasound imaging verified the high-efficiency aggregation of IR780/FA-Nds-DTX in local tumors and accurate evaluation of tumor contour. The therapeutic effect was observed in the experimental group (IR780/FA-Nds-DTX) and four control groups (FA-Nds-IR780, FA-Nds-DTX, FA-Nds and normal saline). After low-intensity focused ultrasound irradiation for 30s induced microbubble blasting after phase transformation in each group, 808nm photothermal therapy apparatus was used to irradiate tumor area in each group. Two-dimensional ultrasound was used to monitor the changes in tumor volume in each group before and at 3 d, 9 d, 15 d after treatment, and the changes in tumor volume rate and inhibition in each group were statistically analyzed and compared.Results:The amount of IR780/ FA-Nds-DTX locally targeted aggregation was the largest, and the average fluorescence intensity of tumor in the experimental group was significantly higher than that of the control groups: IR780/ FA-Nds-DTX group compared with Nds(FITC) group[(5.12±0.69)×10 7 vs (1.06±0.23)×10 7, P<0.05], IR780/FA-Nds-DTX group compared with FA-Nds (FITC) group [(5.12±0.69)×10 7 vs (2.98±0.34)×10 7, P<0.05], IR780/FA-Nds-DTX group compared with IR-780 group [(5.12±0.69)×10 7 vs (1.54±0.42)×10 7, P<0.05], and there was no fluorescence in tumor area in saline group. Further contrast-enhanced ultrasound imaging after nanodroplet phase transformation could more accurately locate the tumor boundary. After 15 days of photothermal ablation combined with chemotherapy, the growth rate of tumor volume in the IR780/ FA-Nds-DTX treatment group was significantly lower than that in the control groups: IR780/FA-Nds-DTX group compared with FA-Nds-IR780 group[(0.105±0.075) vs (0.405±0.175), P<0.05], IR780/ FA-Nds-DTX group compared with FA-Nds-DTX group [(0.105±0.075) vs (1.385±0.035), P<0.05], IR780/ FA-Nds-DTX group compared with FA-Nds group [(0.105±0.075) vs (2.255±0.105), P<0.05], IR780/ FA-Nds-DTX group compared with normal saline group [(0.105±0.075) vs (2.185±0.155), P<0.05]. And the tumor inhibition rate increased significantly: IR780/ FA-Nds-DTX group compared with FA-Nds-IR780 group [(0.93±0.06) vs (0.48±0.17), P<0.05], IR780/ FA-Nds-DTX group compared with FA-Nds-DTX group [(0.93±0.06) vs (-0.51±0.105), P<0.05], IR780/ FA-Nds-DTX group compared with FA-Nds group [(0.93±0.06) vs (-1.63±0.115), P<0.05], IR780/ FA-Nds-DTX group compared with normal saline[(0.93±0.06) vs (-1.35±0.245), P<0.05]. Conclusions:The self-made phase-change ultrasound contrast agents IR780/FA-Nds-DTX have good potential clinical value in targeted detection and combined therapy of pancreatic cancer with small lesions or even metastases.
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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 .
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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 .
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Objective To prepare a 10-hydroxycamptothecin (10-HCPT) loaded folate-receptor targeted phase-change contrast agent (FR-HCPT-PNPCA),and to study the general characteristics including drug loading,phase changing and targeting capability in vitro.Methods Using a method of two-step emulsification,the phase-change nanoparticles loading anticancer drug (10-HCPT) with lipids shell and liquid pefluorocarbon core were prepared.The entrapment efficiency and the drug-loading amounts were studied by high performance liquid chromatography,and the phase transition of the nanoparticles after heating was observed.The targeting ability was evaluated on liver cancer cell line 7721 in vitro.Results The FR-HCPT-PNPCA,with a drug encapsulation rate of about 70.42 ％ and drug loading amounts of about 20.05 ％,was prepared successfully.When being heated to 70℃,obvious phase changing and microbubbles generating could be observed under microscope.In addition,a large amount of FR-HCPT-PNPCA particles could adhere specifically around the 7721 cells.Conclusion The prepared FR-HCPT-PNPCA,which has a stable characteristic and high performance of drug loading and tumor targeting,is expected to become a promising multifunctional molecular ultrasound probe for diagnosis and treatment of tumor.
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Objective To study the effects of phase change material (cooling agent) on the quality of blood after long-distant transportation.Methods A total of 12 bags, packed with pre-chilled phase change materials, were put into regular blood transportation kit, and the new blood transportation kit, which was developed by our hospital. In each kit there were 54 U of red blood cell suspensions. The temperatures in the kit were recorded during the transportation at different times.Results The temperature in the kit was kept between 1—7℃ during the 72h transportation. The temperature met the needs of red blood cell transportation.Conclusion Phase change material could be used as an effective cooling agent for long distance blood transportation.
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Objective To study the mechanism of heat transfer by simulating a complete freezing-thawing process of biological tissue.Methods A numerical model of phase change heat transfer in biological tissue was developed with consideration of the difference of thermophysical properties for normal biological tissue and tumor.The biological tissue was assumed as a porous media.The different thermophysical properties between tissue framework and tissue fluid(as water in tissue,etc) were considered.An apparent heat capacity method was applied to solve the phase change heat transfer problem.Results It was showed that the temperature of biological tissue decreased more quickly during the freezing process when the initial cryoprobe temperature was lower and the cooling-rate of cryoprobe was faster.The temperature of biological tissue increased more quickly with faster warming-rate of cryoprobe in the thawing process.It was also showed that the porosity,blood perfusion rate and metabolic heat generation of the biological tissue had effects on tissue freezing temperature in biological tissue.Conclusion To study the thermal process of biological tissue in cryosurgery will be very helpful for further application in cryosurgery.
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Objective:Temperature keeping is vital in the long distance transportation of red blood cell suspensions in military affairs and emergency.This study aimed to develop a composite phase change material to be used for preserving blood in long time transporation without electricity.Methods: The n-tetradecane was adsorbed to the pore structure of silica aerogel through the capillarity and hydrophobicity of silica aerogel.The efficiency of the phase change material was detected by differential scanning calorimetry.Results: The specific surface area and the adsorption capacity were 863.59 m2/g and 9.16,respectively.The phase change temperature was 5.47℃ and phase change latent heat was 180J/g.Conclusion: The n-tetradecane /silica aerogel composite phase change material could be used for blood preservation.
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The thermal characters such as temperature field, temperature grads and cooling power are very important for sur geons to estimate and improve curative effect. The freezing experiment around a 3.4mm cryoprobe was conducted and a multi dimensional numerical model based on enthalpy method and solved by finite element scheme for the freezing process of simu lative biological tissues during cryosurgery is presented. The results of the numerical solution were validated against experimen taal data .The utility of the numerical solution for the design and application of c ryodevices is demonstrated.