Meta-Analysis of Effects of Early Palliative Care on Health-Related Outcomes Among Advanced Cancer Patients.

BACKGROUND: Early palliative care (PC) has received more attention for improving health-related outcomes for advanced cancer patients in recent years, but the results of previous studies are inconsistent. OBJECTIVES: This study aimed to use meta-analysis and trial sequence analysis to evaluate the effect of early PC on health-related outcomes of advanced cancer patients. METHODS: All English publications were searched in PubMed, Web of Science, Embase, and the Cochrane Library from inception to March 2023, with a restriction that the study type was a randomized controlled trial. RESULTS: The results showed that early PC positively affected quality of life, satisfaction with care, and symptom burden reduction. However, early PC had no significant effect on anxiety or survival. Trial sequence analysis results showed that the effect of early PC on the quality of life was stable. DISCUSSION: This systematic review suggested that early PC could positively affect health-related outcomes for advanced cancer patients. Early PC can be used widely in clinical settings to improve health-related outcomes of advanced cancer. However, because of the trial sequence analysis results, further well-designed, clinical, randomized controlled trials with larger sample sizes are necessary to draw definitive conclusions.

Factors Associated With Parenting Stress in Parents of Children With Nephrotic Syndrome: A Cross-Sectional Study.

Limited empirical studies were identified to quantify parenting stress in parents of children with nephrotic syndrome (NS). This cross-sectional study aimed to address this gap by examining the prevalence and factors associated with parenting stress. Two hundred two Chinese parents of children with NS were investigated by using the Parenting Stress Index-Short Form (PSI-SF), the Parenting Sense of Competence Scale (PSCS), the Social Support Rating Scale (SSRS), and a demographic questionnaire. The results showed that parents of children with NS experienced higher parenting stress, and 67.8% of participants reported clinical levels of parenting stress. Fathers, parents with a primary education background, low social support and parenting sense of competence, and children with a prolonged treatment childhood NS reported higher parenting stress. Developing corresponding improvement interventions targeting parenting sense of competence, or providing extra disease-related support and education for parents might lessen parenting stress.

Preparation and evaluation of a biomimetic scaffold with porosity gradients in vitro.

A novel biodegradable scaffold based on mimetic a natural bone tissue morphology with a porosity gradient structure was prepared in this paper. The result of surface morphology indicated that a graded porous structure was formed in the fabricated scaffold, where the dense layer (0%) was connected with the most porous layer (60%) by a middling porous layer (30%). To evaluate the degradability, graded porous scaffolds compared with homogeneous scaffolds were placed into a Tris-HCl buffer solution (pH = 7.4) for 28 days. It was found that both scaffolds presented the same degradation trend, and the graded porous structure did not change the original degradability of the scaffold. Moreover, the compressive strength of the graded porous scaffold was better than that of conventional homogeneous scaffold with the increase of degradation time, and the graded porous structure can enhanced the mechanical property of the scaffold. These findings suggest that this biodegradable and porosity-graded scaffold may be a new promising scaffold for loaded bone implant.

Application of K/Sr co-doped calcium polyphosphate bioceramic as scaffolds for bone substitutes.

Ion doping is one of the most important methods to modify the properties of bioceramics for better biodegrade abilities, biomechanical properties, and biocompatibilities. This paper presents a novel ion doping method applied in calcium polyphosphate (CPP)-based bioceramic scaffolds substituted by potassium and strontium ions (K/Sr) to form (K/Sr-CPP) scaffolds for bone tissue regeneration. The microstructure and crystallization of the scaffolds were detected by scanning electron microscopy and X-ray diffraction. Compressive strength and degradation tests were assessed to evaluate the mechanical and chemical stabilities of K/Sr-CPP in vitro. The cell biocompatibility was measured with respect to the cytotoxicity of the extractions of scaffolds. Muscle pouches and bone implantation were performed to evaluate the biodegradability and osteoconductivity of the scaffolds. The results indicated that the obtained K/Sr-CPP scaffolds had a single beta-CPP phase. The unit cell volume and average grain size increased but the crystallization decreased after the ions were doped into the CPP structure. The K/Sr-CPP scaffolds yielded a higher compressive strength and a better degradation property than the pure CPP scaffold. The MTT assay and in vivo results reveal that the K/Sr-CPP scaffolds exhibited a better cell biocompatibility and a tissue biocompatibility than CPP and hydroxyapatite scaffolds. This study proves the potential applications of K/Sr-CPP scaffolds in bone repair.

Delivery of demineralized bone matrix powder using a thermogelling chitosan carrier.

Demineralized bone matrix (DBM) powder is widely used for bone regeneration due to its osteoinductivity and osteoconductivity. However, difficulties with handling, its tendency to migrate from graft sites, and lack of stability after surgery can sometimes limit the clinical utility of this material. In this work, the possibility of using a thermogelling chitosan carrier to deliver DBM powder was assessed. The DBM-thermogelling putty improved handling and formed a gel-like composite in situ at body temperature within a clinically relevant time period. The properties of the formed composite, including morphology, porosity, mechanical properties, equilibrium swelling as well as degradability, are significantly influenced by the ratio of DBM to thermogelling chitosan. The in vitro study showed that the alkaline phosphatase activity of C2C12 cells encapsulated in the composite was steadily increased with culture time. The in vivo study showed that increased DBM content in the DBM-thermogelling chitosan induced ectopic bone formation in a nude rat model. The diffusion of growth factor from the DBM-thermogelling chitosan as well as the host-implant interactions are discussed.

A novel alkali metals/strontium co-substituted calcium polyphosphate scaffolds in bone tissue engineering.

Our purpose of this study is to develop potassium or sodium/strontium co-substituted calcium polyphosphate (K/Sr-CPP or Na/Sr-CPP) bioceramics in application of bone repairing scaffold. The incorporation of K, Na, and Sr into CPP substrate via a calcining-sintering process was confirmed by X-ray diffractometry and inductively coupled plasma atomic emission spectroscopy. In vitro degradation study of co-substituted CPP indicated the incorporation of alkali metal elements promoted the degradability of CPP, and the scanning electron microscope showed the apatite-like minerals were precipitated on the surface of co-substituted CPP. The compress resistant strength of co-substituted CPP was elevated by dopants. The MTT assay and confocal laser-scanning microscope on osteoblasts culturing with co-substituted CPP showed no cytotoxicity. The cell proliferation on co-substituted CPP was even better than others. Thus, this co-substituted CPP bioceramics might have potential of applications in orthopedic field.

A novel strontium-doped calcium polyphosphate/erythromycin/poly(vinyl alcohol) composite for bone tissue engineering.

It is our goal to develop bactericidal bone scaffolds with osteointegration potential. In this study, poly(vinyl alcohol) (PVA) coating (7%) was applied to an erythromycin (EM)-impregnated strontium-doped calcium polyphosphate (SCPP) scaffold using a simple slurry dipping method. MicroCT analysis showed that PVA coating reduced the average pore size and the percentage of pore interconnectivity to some extent. Compressive strength tests confirmed that the PVA coating significantly increased material elasticity and slightly enhanced the scaffold mechanical strength. It was also confirmed that the PVA coatings allowed a sustained EM release that is controlled by diffusion through the intact PVA hydrogel layer, irrespective of the drug solubility. PVA coating did not inhibit the EM bioactivity when the scaffolds were immersed in simulated body fluid for up to 4 weeks. EM released from SCPP-EM-PVA composite scaffolds maintained its capability of bacterial growth (S. aureus) inhibition. PVA coating is biocompatible and nontoxic to MC3T3 preosteoblast cells. Furthermore, we found that SCPP-EM-PVA composite scaffolds and their eluants remarkably inhibited RANKL-induced osteoclastogenesis in a murine RAW 264.7 macrophage cell line. Thus, this unique multifunctional bioactive composite scaffold has the potential to provide controlled delivery of relevant drugs for bone tissue engineering.

[Preparation and properties of calcium polyphosphate-based composite scaffold for bone tissue engineering].

Calcium polyphosphate (CPP) is a new type of degradable material for bone repair, yet it is fragile and is not so controllable in regard to degradation. For increasing biological activity and close proximity to natural bone structure, in this experiment, we chose chitosan (CS) and its derivative carboxymethyl chitosan (CMC) as the extracellular matrix structure for the organic phase. Aldehyde sodium alginate (ADA) was used as natural cross-linker. The binary (CPP/CMC) and ternary (CPP/CMC/CS) composite scaffolds were prepared by the "multiple composite-cross-linking method". The degradation laws of the two materials were investigated through the weight loss of scaffolds, the pH value of degradation solution, the compressive strength and the surface morphology characterization. The results showed that the composite scaffolds had good interface and the compressive strength increased greatly, but the organic phase of dual-phase composite scaffolds degraded quickly, while degradation controllability and mechanical properties of ternary composite scaffold were significantly improved. All the above findings show that the method of ternary complex scaffold preparation is useful for the design and preparation of bone tissue engineering materials.

[Recent progress of researches on scaffolds for tissue engineered meniscus].

Tissue engineered meniscus provides a novel approach for the treatment of severe meniscus injury. The researches on scaffold for tissue engineered meniscus is an essential element. The researches on scaffolds for tissue engineered meniscus, including natural biomaterials and synthetic polymer, have made great advances in recent years. At present, collagen meniscus implants have been used in clinical practice. As hydrogel is characterized by having high water content and good biocompatibility, being similar to extracellular matrix in structure, and being able to provide access to microsurgery, it has become the hotspot field in recent years. Meanwhile, the combinatorial scaffold material advantages of biological composite tissue engineered scaffolds also illuminate the key point of research on meniscal scaffolds. This paper reviews the recent progress in betterment of the scaffolds so as to provide a theoretical and practical basis for further researches of tissue engineered meniscus.

Preparation and characterization of nonfouling polymer brushes on poly(ethylene terephthalate) film surfaces.

In this study, a surface grafting of nonfouling poly(ethylene glycol) methyl ether acrylate (PEGMA) on poly(ethylene terephthalate) (PET) was carried out via surface-initiated atom-transfer radical polymerization (SI-ATRP) to improve hemocompatibility of polymer based biomaterials. To do this, the coupling agent with hydroxyl groups for the ATRP initiator was first anchored on the surface of PET films using photochemical method, and then these hydroxyl groups were esterified by bromoisobutyryl bromide, from which PET with various main chain lengths of PEGMA was prepared. The structures and properties of modified PET surfaces were investigated using water contact angle (WAC), ATR-FTIR, X-ray photoelectron spectroscopy (XPS) and Atomic force microscopy (AFM). The molecular weights of the free polymer from solution were determined by gel permeation chromatography (GPC). These results indicated that grafting of PEGMA on PET film is a simple way to change its surface properties. The protein adsorption resistance on the surfaces of PET was primarily evaluated by an enzyme-linked immunosorbent assay (ELISA). The result demonstrated that the protein adsorption could be well suppressed by poly(PEGMA) brush structure on the surface of PET. This work provides a new approach for polymers to enhance their biocompatibility.

In vivo study of porous strontium-doped calcium polyphosphate scaffolds for bone substitute applications.

The purpose of this study was to investigate in vivo biocompatibility and osteogenesis as well as degradability of the porous strontium-doped calcium polyphosphate (SCPP) scaffolds as a biomaterial for bone substitute applications. The evaluation was performed on a rabbit model over a period of 16 weeks by histology combined with image analysis, X-ray microradiography and immunohistochemistry methods. The histological and X-ray microradiographic results showed that the SCPP scaffold exhibited good biocompatibility and extensive osteoconductivity with host bone. Moreover, a significant more bone formation was observed in the SCPP group compared with that in the CPP group, especially at the initial stage after implantation. New bone volumes (NBVs) of the SCPP group determined at week 4, 8 and 16 were 14, 27 and 45%, respectively. Accordingly, NBVs of the CPP group were 10, 19 and 40%. Immunohistochemical results revealed that both the expression of collagen type I and bone morphogenetic proteins in the SCPP group were higher than that in the CPP group, which might be associated with the release of strontium ions during the implantation. In addition, during 16 weeks implantation the SCPP scaffold exhibited similar degradability with the CPP scaffold in vivo. Both scaffolds showed the greatest degradation rate for the first 4 weeks, and then the degradation rate gradually decreased. The results presented in this study demonstrated that SCPP scaffold can be considered as a biocompatible material, making it attractive for bone substitute application purposes.

Behavior of endothelial cells regulated by a dynamically changed microenvironment of biodegradable PLLA-PC.

The influence of PLLA-PC membranes on the behavior of vascular ECs is studied. It was found that the membranes were not cytotoxic. The cell adhesion and spread on PLLA-PC 30/1 were initially depressed. After 1 d, however, cells attached and spread on the copolymer, and proliferated beyond 2 d. To elucidate the mechanism of this behavior, the surface morphology and the degradation products of the PLLA/PC 30/1 membrane during the culture period were tested, and Fg adsorption to the membranes was examined. It is concluded that the behavior of ECs can be regulated by a dynamically changed microenvironment of the PLLA-PC membrane. PLLA-PC copolymers might therefore serve as a novel material for tissue engineering.

The study on the degradation and mineralization mechanism of ion-doped calcium polyphosphate in vitro.

Doping with different trace elements can significantly change the original degradability, mineralization, and biological properties of bone repair material. According to the fundamental research on prepared calcium polyphosphate (CPP) as a bone repair material by our group, this article began further exploration on the effect of doping different trace elements (K, Na, Mg, Zn, Sr) into CPP on its degradability and mineralization soaking in simulated body fluids. The results indicated that doped elements significantly changed the lattice parameters and cell volume of crystal, resulted in different types of crystal defect and surface charge distribution, and consequently changed the original degradability and mineralization of CPP. The conclusion is that doped ions with relatively smaller ionic radius and equivalent positive charge compared with Ca(2+) can greatly promote the degradability and mineralization of CPP, whereas doped ions with equivalent ionic radius and diverse positive charges compared with Ca(2+) provide less contribution on promoting the degradability and mineralization or even counteract.

[The hydrophilicity and cell affinity of polylactic acid containg bionic function group of phosphorylcholine].

A series of novel biodegradable and bionic functional polymers, PLLA-PC-PLLA, were synthesized using L-lactide ring-opening polymerization by L-a-Glycerophosphorylcholine (PC) from nature source. The hydrophilicity of the polymers was investigated. The results made known that, as PC group was brought into the backbone of PLLA, PLLA-PC-PLLA gained much better hydrophilicity than did PLLA, and polar phosphatidylcholines probably transferred to the sample surface in aqueous environment. The relative growth ratios of ECV304 cells to the lixivium of all PLLA-PC-PLLA were higher than 84% in 5 d culture. The cells adhesion of ECV304 on the films of PLLA-PC-PLLA lagged as compared to that on PLLA, but they could proliferate and cover the films in total. The difference between PLLA-PC-PLLA and PLLA was due to the existence of PC group. Thus, PLLA-PC-PLLA, the same as PLLA, are not cytotoxic, and ECV304 can attach and proliferate on them. PLLA-PC-PLLA have potential applications in the fields of tissue engineering and drug delivery system.

Preparation and endothelialization of decellularised vascular scaffold for tissue-engineered blood vessel.

The proliferation of cells on the decellularised tissues fixed by chemical crosslinking agent is retarded for cytotoxicity of crosslinked tissues. To overcome this disadvantage, we prepared the decellularised vascular scaffold through fixing the porcine thoracic arteries with 40 mL/L ethylene glycol diglycidyl ether (EGDE), and reduced the cytotoxicity of this scaffold by treating it with lysine and coating it with type I collagen, finally endothelialized it in vitro. The EGDE-fixed porcine thoracic arteries were examined morphologically. The fixation index determination and the biomechanics test were also performed. Human umbilical vein endothelial cells (HUVECs) were seeded on the type I collagen-coated surface of different modified vascular tissues (fixed with glutaraldehyde or EGDE or EGDE + lysine), and the growths of HUVECs on the specimens were demonstrated by means of MTT test. Finally, HUVECs were seeded on the luminal surface of the modified porcine vascular scaffolds which were respectively treated in the same manner described above, and then cultured for 7 days. On the seventh day, the HUVECs on the specimens were examined by means of light microscopy, scanning electron microscopy and transmission electron microscopy (TEM). The antigenicity of the vascular tissues can be diminished by EGDE through getting rid of cell in the vascular tissues or reducing the level of free amino groups in the vascular tissues. In this study, it was also found that the EGDE-fixed porcine vascular tissues appeared similar to the native porcine vascular tissues in color and mechanical properties. After treated by 2% lysine and coated with type I collagen, the EGDE-fixed porcine vascular tissues were characterized by low cytotoxicity and good cytocompatible. The HUVECs can proliferate well on the modified vascular tissues, and easily make it endothelialized. The results showed that the modified porcine vascular scaffolds should be a promising material for fabricating scaffold of tissue-engineered blood vessel.

[Effect of processing parameters on the degradation of calcium polyphosphate bioceramic for bone tissue scaffolds].

This study was undertaken to elucidate the degradation regularity of calcium polyphosphate (CPP) scaffolds with different preparation parameters. CPP scaffolds with different main crystalline phases were prepared by controlling the particle size of the calcining stuff and the calcining heat. Specimens were soaked into Tris-buffer solution and simulated body fluid (SBF) for 60 days. Results show: alpha-CPP degrades faster than does beta-CPP, and beta-CPP degrades faster than does gamma-CPP; the lower the sinter temperature, the better the degradation of CPP morever, the degradation rate of CPP is inversely proportional to the original particle size. These data suggest that crystal type, sinter temperature and particle size influence the degradation rate of CPP markedly.

[Research on intelligent controlled drug delivery with polymer].

The intelligent controlled drug delivery systems are a series of the preparations including microcapsules or nanocapsules composed of intelligent polymers and medication. The properties of preparations can change with the external stimuli such as pH value, temperature, chemical substance, light, electricity and magnetism. According to this properties, the drug delivery can be intelligently controlled. This paper has reviewed research on syntheses and applications of intelligent controlled drug delivery systems with polymers.

[Progress in study of self-assembling peptides].

Self-assembly of peptides is ubiquitous in the body of creatures. The molecules of peptides combine with each other to form proteins with different functions through self-assembly. The formation of a specific conformation of one type of protein is owing to the self-assembly of its compositive amino acids. So, researchers can design self-assembly of peptides at the molecular level and can control its formation and configuration. It has the potential for application in the preparation of new medicines and biomaterials. In recent years, self-assembling peptides have been increasingly high-lighted and used to simulate the function of natural biomolecules, to synthesize peptide-medicine, and to serve as the carriers of medicine.

[Structure and performance of calcium polyphosphate for bone tissue engineering].

Porous calcium polyphosphate (CPP) has shown promise of tissue engineered implant application because of the biocompatibility and biodegradation. CPP with different polymerization degree were prepared by controlling the calcining time, and its polymerization degree could be calculated by developed method in this paper. Different crystal types CPP were prepared by quenching from the melt and crystallization of amorphous CPP. From the in vitro degradation, carried out in Tris-HCl buffer, the degradation velocity of CPP was controllable. The weight loss of CPP with different polymerization degrees and crystal types were different. With the increasing of polymerization degree, the weight loss during the degradation was decreasing, contrarily the strength of CPP was increasing. The amorphous CPP could degrade completely in 17 days while gamma-CPP do completely in 25 days. The degradation velocity beta-CPP and alpha-CPP was slower than gamma-CPP and the weight loss was about 12% and 5% respectively. The results of this study indicate that CPP have potential applications for bone tissue engineering as inorganic polymeric biomaterials.

[Effect of RGD peptide on adhesive stability of human umbilical vein endothelial cell on polyethylene terephthalate surface].

In this study for exploring the effect of RGD peptide on adhesive stability of endothelial cells biomaterial surface, all materials were divided into three groups, RGD group (PET covalently grafted synthetic RGD peptides), control group (PET precoated with fibronectin) and blank group (Non-coated surface). Cultured human umbilical vein endothelial cells (HUVECs) were seeded on the materials, then adhesive stability of HUVECs on the varied PET surfaces was observed under steady flow condition, and effects of shear stress and shear time on adherent cells were compared. The results showed that the resistance adherent endothelial cells to detachment by flow was shear stress and shear time dependent. Comparison three groups under the same condition revealed that the ECs retention rates of RGD-grafted or fibronectin-coated group were much higher than that of the non-coated group. Under 8.19 dyne/cm2 shear stress after 4h, retention rates were 13.73% (blank group), 43.33% (RGD group) and 40.75% (control group) respectively. These data indicated that RGD peptide can improve the adhesive stability of endothelial cell on biomaterial and the effect of RGD in vivo needs further studies.