In Vitro Fertilization (IVF) is generally accepted as the most effective treatment for infertility. Its success depends on the correct and meticulous implementation of each stage in the procedure. The process of systematically examining embryos is standardized through the use of internationally recognized criteria. On the other hand, the evaluation of oocyte quality continues to be conducted more arbitrarily. A morphologically good quality mature human oocyte is universally described as one that shows a homogeneous cytoplasm, has a single polar body (PB), an approprate zona pellucida (ZP) thickness and a proper perivitelline space (PVS). An abnormality in one or more of these features are very common in IVF cycles and may be related to several factors that are extrinsic and intrinsic to the patient. There has been extensive speculation over whether specific anomalies in the structure of oocytes can suggest a reduced developmental capacity. The most notable among the dysmorphisms of oocytes are the severe morphological deviations, such as smooth endoplasmic reticulum clusters, cytoplasm granularity, and giant oocytes that are related to genetic abnormalities, and extra-cytoplasmic parameters such as PB morphology, the PVS and ZP abnormalities that may indicate oocyte ageing. This paper acknowledges the significance of oocyte morphology grading as an important and practical predictor of a successful IVF outcome and it can serve as a supplementary measure to embryonic assessment in order to optimize efficacy of assisted reproductive technology (ART). It discusses the fundamental knowledge that infertility specialists and embryologists should possess to enable its routine application in the ART laboratory.

Some women may not be able to carry their own children even when capable of conceiving biological offspring. In-vitro fertilization and embryo-transfer (IVF-ET) through surrogacy can now make this possible for these women. Surrogacy however, is still considered unacceptable in the Philippines due to moral and legal issues. This article will explore the need and acceptability of surrogacy in this age of IVF-ET in a country where the prevailing social norms and religious values still disapprove of third-party assisted reproductive technology (ART). Medical indications that would benefit from gestational surrogacy were enumerated and briefly discussed. The differentiation between traditional and gestation surrogacy, as well as commercial and altruistic surrogacy were defined. IVF with gestational surrogacy is a feasible solution to a number of medical difficulties in the carrying of a gestation. Strictly regulating the practice and restricting its use only to cases with legitimate medical indications will prevent its misuse and exploitation. Moral issues, admittedly will still remain an issue particularly for commercial surrogacy. However, limiting these only to altruistic and gestational surrogacy in some cases may be an acceptable compromise.
Child ; Fertilization in Vitro ; Reproductive Techniques, Assisted

OBJECTIVE: To investigate the preparation of decellularized small intestinal submucosa (dSIS) sponge scaffolds with chelated strontium (Sr) ions at different pH values, and to select the appropriate pH values for synthesizing Sr/dSIS scaffolds using the physicochemical properties and biocompatibility of the scaffolds as evaluation indexes. METHODS: (1) Sr/dSIS scaffolds preparation and grouping: After mixing dSIS solution and strontium chloride solution in equal volumes, adjusting pH of the solution to 3, 5, 7, and 9 respectively, porous scaffolds were prepared by freeze-drying method after full reaction at 37℃, which were named Sr/dSIS-3, -5, -7, and -9 respectively, and the dSIS scaffolds were used as the control group. (2) Physicochemical property evaluation: The bulk morphology of the scaffolds was observed in each group, the microscopic morphology analyzed by scanning electron microscopy, and the porosity and pore size determined, the surface elements analyzed by energy spectroscopy, the structure of functional groups analyzed by infrared spectroscopy, the chelation rate determined by atomic spectrophotometry, the water absorption rate detected by using specific gravity method, and the compression strength evaluated by universal mechanical testing machine.(3) Biocompatibility evaluation: The cytotoxicity and proliferative effect to bone mesenchymal stem cells (BMSCs) of each group were evaluated by Calcein-AM/PI double staining method. RESULTS: Scanning electron microscopy showed that the scaffolds of each group had an interconnected three-dimensional porous structure with no statistical difference in pore size and porosity. Energy spectrum analysis showed that strontium could be detected in Sr/dSIS-5, -7 and -9 groups, and strontium was uniformly distributed in the scaffolds. Functional group analysis further supported the formation of chelates in the Sr/dSIS-5, -7 and -9 groups. Chelation rate analysis showed that the Sr/dSIS-7 group had the highest strontium chelation rate, which was statistically different from the other groups (P < 0.05). The scaffolds in all the groups had good water absorption. The scaffolds in Sr/dSIS-5, -7 and -9 groups showed significantly improved mechanical properties compared with the control group (P < 0.05). The scaffolds in all the groups had good biocompatibility, and the Sr/dSIS-7 group showed the best proliferation of BMSCs. CONCLUSION When pH was 7, the Sr/dSIS scaffolds showed the highest strontium chelation rate and the best proliferation effect of BMSCs, which was the ideal pH value for the preparation of the Sr/dSIS scaffolds.
Tissue Scaffolds/chemistry* ; Biocompatible Materials ; Strontium/pharmacology* ; Ions ; Hydrogen-Ion Concentration ; Tissue Engineering/methods* ; Porosity

Pulpitis, periodontitis, jaw bone defect, and temporomandibular joint damage are common oral and maxillofacial diseases in clinic, but traditional treatments are unable to restore the structure and function of the injured tissues. Due to their good biocompatibility, biodegradability, antioxidant effect, anti-inflammatory activity, and broad-spectrum antimicrobial property, chitosan-based hydrogels have shown broad applicable prospects in the field of oral tissue engineering. Quaternization, carboxymethylation, and sulfonation are common chemical modification strategies to improve the physicochemical properties and biological functions of chitosan-based hydrogels, while the construction of hydrogel composite systems via carrying porous microspheres or nanoparticles can achieve local sequential delivery of diverse drugs or bioactive factors, laying a solid foundation for the well-organized regeneration of defective tissues. Chemical cross-linking is commonly employed to fabricate irreversible permanent chitosan gels, and physical cross-linking enables the formation of reversible gel networks. Representing suitable scaffold biomaterials, several chitosan-based hydrogels transplanted with stem cells, growth factors or exosomes have been used in an attempt to regenerate oral soft and hard tissues. Currently, remarkable advances have been made in promoting the regeneration of pulp-dentin complex, cementum-periodontium-alveolar bone complex, jaw bone, and cartilage. However, the clinical translation of chitosan-based hydrogels still encounters multiple challenges. In future, more in vivo clinical exploration under the conditions of oral complex microenvironments should be performed, and the combined application of chitosan-based hydrogels and a variety of bioactive factors, biomaterials, and state-of-the-art biotechnologies can be pursued in order to realize multifaceted complete regeneration of oral tissue.
Chitosan/chemistry* ; Tissue Engineering ; Hydrogels/chemistry* ; Biocompatible Materials/chemistry* ; Cartilage ; Tissue Scaffolds/chemistry*

The cardiovascular patch, served as artificial graft materials to replace heart or vascular tissue defect, is still playing a key role in cardiovascular surgeries. The defects of traditional cardiovascular patch materials may determine its unsatisfactory long-term effect or fatal complications after surgery. Recent studies on many new materials (such as tissue engineered materials, three-dimensional printed materials, etc) are being developed. Patch materials have been widely used in clinical procedures of cardiovascular surgeries such as angioplasty, cardiac atrioventricular wall or atrioventricular septum repair, and valve replacement. The clinical demand for better cardiovascular patch materials is still urgent. However, the cardiovascular patch materials need to adapt to normal coagulation mechanism and durability, promote short-term endothelialization after surgery, and inhibit long-term postoperative intimal hyperplasia, its research and development process is relatively complicated. Understanding the characteristics of various cardiovascular patch materials and their application in cardiovascular surgeries is important for the selection of new clinical surgical materials and the development of cardiovascular patch materials.
Cardiac Surgical Procedures/methods* ; Tissue Engineering ; Heart Ventricles ; Heart Atria ; Treatment Outcome

OBJECTIVE: The prepare decellularized extracellular matrix (ECM) scaffold materials derived from human cervical carcinoma tissues for 3D culture of cervical carcinoma cells. METHODS: Fresh human cervical carcinoma tissues were treated with sodium lauryl ether sulfate (SLES) solution to prepare decellularized ECM scaffolds. The scaffolds were examined for ECM microstructure and residual contents of key ECM components (collagen, glycosaminoglycan, and elastin) and genetic materials by pathological staining and biochemical content analysis. In vitro 3D culture models were established by injecting cultured cervical cancer cells into the prepared ECM scaffolds. The cells in the recellularized scaffolds were compared with those in a conventional 2D culture system for cell behaviors including migration, proliferation and epithelial-mesenchymal transition (EMT) wsing HE staining, immunohistochemical staining and molecular biological technology analysis. Resistance to 5-fluorouracil (5-Fu) of the cells in the two culture systems was tested by analyzing the cell apoptosis rates via flow cytometry. RESULTS: SLES treatment effectively removed cells and genetic materials from human cervical carcinoma tissues but well preserved the microenvironment structure and biological activity of ECM. Compared with the 2D culture system, the 3D culture models significantly promoted proliferation, migration, EMT and 5-Fu resistance of human cervical cancer cells. CONCLUSION The decellularized ECM scaffolds prepared using human cervical carcinoma tissues provide the basis for construction of in vitro 3D culture models for human cervical cancer cells.
Female ; Humans ; Decellularized Extracellular Matrix ; Extracellular Matrix ; Uterine Cervical Neoplasms ; Tissue Scaffolds/chemistry* ; Carcinoma ; Fluorouracil/pharmacology* ; Tissue Engineering ; Tumor Microenvironment

Droplet microfluidics technology offers refined control over the flows of multiple fluids in micro/nano-scale, enabling fabrication of micro/nano-droplets with precisely adjustable structures and compositions in a high-throughput manner. With the combination of proper hydrogel materials and preparation methods, single or multiple cells can be efficiently encapsulated into hydrogels to produce cell-loaded hydrogel microspheres. The cell-loaded hydrogel microspheres can provide a three-dimensional, relatively independent and controllable microenvironment for cell proliferation and differentiation, which is of great value for three-dimensional cell culture, tissue engineering and regenerative medicine, stem cell research, single cell study and many other biological science fields. In this review, the preparation methods of cell-loaded hydrogel microspheres based on droplet microfluidics and its applications in biomedical field are summarized and future prospects are proposed.
Hydrogels/chemistry* ; Microfluidics/methods* ; Microspheres ; Regenerative Medicine ; Tissue Engineering/methods*

Collagen, which widely exists in skin, bone, muscle and other tissues, is a major structural protein in mammalian extracellular matrix. It participates in cell proliferation, differentiation, migration and signal transmission, plays an important role in tissue support and repair and exerts a protective effect. Collagen is widely used in tissue engineering, clinical medicine, food industry, packaging materials, cosmetics and medical beauty due to its good biological characteristics. This paper reviews the biological characteristics of collagen and its application in bioengineering research and development in recent years. Finally, we prospect the future application of collagen as a biomimetic material.
Animals ; Collagen/analysis* ; Tissue Engineering/methods* ; Extracellular Matrix/metabolism* ; Biomimetic Materials/chemistry* ; Bone and Bones ; Tissue Scaffolds ; Mammals/metabolism*

The development of synthetic biology has greatly promoted the construction of microbial cell factories, providing an important strategy for green and efficient chemical production. However, the bottleneck of poor tolerance to harsh industrial environments has become the key factor hampering the productivity of microbial cells. Adaptive evolution is an important method to domesticate microorganisms for a certain period by applying targeted selection pressure to obtain desired phenotypic or physiological properties that are adapted to a specific environment. Recently, with the development of technologies such as microfluidics, biosensors, and omics analysis, adaptive evolution has laid the foundation for efficient productivity of microbial cell factories. Herein, we discuss the key technologies of adaptive evolution and their important applications in improvement of environmental tolerance and production efficiency of microbial cell factories. Moreover, we looked forward to the prospects of adaptive evolution to realize industrial production by microbial cell factories.
Metabolic Engineering ; Industrial Microbiology/methods* ; Synthetic Biology ; Environment ; Industry

In the field of plastic and reconstructive surgery, the loss of organs or tissues caused by diseases or injuries has resulted in challenges, such as donor shortage and immunosuppression. In recent years, with the development of regenerative medicine, the decellularization-recellularization strategy seems to be a promising and attractive method to resolve these difficulties. The decellularized extracellular matrix contains no cells and genetic materials, while retaining the complex ultrastructure, and it can be used as a scaffold for cell seeding and subsequent transplantation, thereby promoting the regeneration of diseased or damaged tissues and organs. This review provided an overview of decellularization-recellularization technique, and mainly concentrated on the application of decellularization-recellularization technique in the field of plastic and reconstructive surgery, including the remodeling of skin, nose, ears, face, and limbs. Finally, we proposed the challenges in and the direction of future development of decellularization-recellularization technique in plastic surgery.
Tissue Engineering/methods* ; Tissue Scaffolds/chemistry* ; Surgery, Plastic ; Regenerative Medicine/methods* ; Extracellular Matrix