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Kinship testing is widely needed in forensic science practice. This paper reviews the definitions of common concepts, and summarizes the basic principles, advantages and disadvantages, and application scope of kinship analysis methods, including identity by state (IBS) method, likelihood ratio (LR) method, method of moment (MoM), and identity by descent (IBD) segment method. This paper also discusses the research hotspots of challenging kinship testing, complex kinship testing, forensic genetic genealogy analysis, and non-human biological samples.
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Humans , DNA Fingerprinting , Forensic Genetics/methods , Forensic Sciences , PedigreeABSTRACT
Objective: This study is unique as it examines biological materials brought to the emergency department. The purpose of this study was to investigate the reasons behind the presence of nonhuman biological material in the emergency department.Methods: The materials brought were photographed and a pre-prepared survey form was filled in following examination.Results: A total of 46 biological materials were brought to the emergency department within a 12-month period. Ticks were the most frequently brought material, and the most common reason for bringing them was to get the creature removed from the body. Situations in which the physician did not have knowledge about the material were more frequent among those that were neutral about being satisfied with the attitude of the physician towards the material brought, and satisfaction was higher in cases when the physician was knowledgeable, although this was not statistically significant.Conclusion: Physicians should not condemn biological materials brought into the department after exposure. If possible, they should try to gain more knowledge about them. If the material is not to be stored, once it is made sure that it is not dangerous, it should be disposed of in a medical waste bin. Physicians should be knowledgeable toward the frequency and the types of such agents in their region.
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BACKGROUND: The dense microstructure of biological scaffolds and the limitation of cell growth microenvironment are the two major difficulties in the application of biological scaffolds in bone tissue repair. OBJECTIVE: To prepare fluffy hydroxyapatite/polylactic acid composite fiber scaffold, so that cells can easily enter into the scaffold and to realize three-dimensional culture of bone marrow mesenchymal stem cells. METHODS: Fluffy hydroxyapatite/polylactic acid composite scaffold was prepared by using modified electrospinning technology combined with biomineralization. The physical and chemical properties of the fiber scaffold were measured and observed. Human bone marrow mesenchymal stem cells were inoculated on the fluffy hydroxyapatite/polylactic acid composite scaffold and traditional hydroxyapatite/polylactic acid composite scaffold. Cell proliferation, adherence and morphological changes were detected. RESULTS AND CONCLUSION: (1) The thickness of hydroxyapatite coating in the fluffy hydroxyapatite/polylactic acid composite scaffold was about 8.3μ m, most of hydroxyapatite fibers were in discrete state with a diameter of 8-14μm. The fibers were connected by pores, and the pore diameter was (65±35) μm. The surface area, porosity and water absorption of the scaffold were significantly higher than those of the traditional scaffold (P<0.01).(2) After 12 hours of culture, the adherence of bone marrow mesenchymal stem cells on the two scaffolds was similar, 83% and 81% cells adhered on the traditional and fluffy scaffolds, respectively. (3) After 7 days of culture, the number of proliferated cells in the fluffy hydroxyapatite/polylactic acid composite scaffold was significantly more than that in the traditional hydroxyapatite/polylactic acid composite scaffold (P<0.01).(4) After 7 days of culture, FDA staining and scanning electric microscopy showed that cell-cell independent shape appeared in the traditional scaffold. A large number of cells appeared in the fluffy scaffold and grew into cell clusters with high cell activity, which formed a cell-fiber construction. These results indicate that this new type hydroxyapatite/polylactic acid composite scaffold is beneficial for cell entry and proliferation.
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BACKGROUND: Calcium citrate has been used as calcium supplement, anticoagulant, anti-inflammatory agent and bone repair material in biomedical fields. OBJECTIVE: To describe the basic properties of calcium citrate, summarize and discuss the preparation process of calcium citrate and its main applications in biomedical field. METHODS: The research literature related to calcium citrate was searched on the Web of science, CNKI, Medline and other databases by computer. The main key words were “calcium citrate, bone repairing material, citrate and calcium phosphate” in English and “calcium citrate, bone repair materials” in Chinese. The searching time was from February 1920 to February 2020. RESULTS AND CONCLUSION: With the development and exploration of medical materials, it is necessary to change the original process to improve the biological activity of medical calcium citrate. It is an inevitable trend to obtain calcium citrate with various micro-morphology and high biological activity by controllable synthesis method. Calcium citrate is widely used as calcium supplement, anti-inflammatory agent, anticoagulant, bone repair material and other non-medical applications. Its advantages are being gradually explored by researchers. The preparation method plays a decisive role in the application field of calcium citrate. Different internal structure and size will bring different application fields, from the smallest chemical bond connection to the macroscopic morphology or mechanical properties. These factors may be the results of the dedicated exploration of researchers.
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BACKGROUND: The dense microstructure of biological scaffolds and the limitation of cell growth microenvironment are the two major difficulties in the application of biological scaffolds in bone tissue repair. OBJECTIVE: To prepare fluffy hydroxyapatite/polylactic acid composite fiber scaffold, so that cells can easily enter into the scaffold and to realize three-dimensional culture of bone marrow mesenchymal stem cells. METHODS: Fluffy hydroxyapatite/polylactic acid composite scaffold was prepared by using modified electrospinning technology combined with biomineralization. The physical and chemical properties of the fiber scaffold were measured and observed. Human bone marrow mesenchymal stem cells were inoculated on the fluffy hydroxyapatite/polylactic acid composite scaffold and traditional hydroxyapatite/polylactic acid composite scaffold. Cell proliferation, adherence and morphological changes were detected. RESULTS AND CONCLUSION: (1) The thickness of hydroxyapatite coating in the fluffy hydroxyapatite/polylactic acid composite scaffold was about 8.3 µm, most of hydroxyapatite fibers were in discrete state with a diameter of 8-14 µm. The fibers were connected by pores, and the pore diameter was (65±35) µm. The surface area, porosity and water absorption of the scaffold were significantly higher than those of the traditional scaffold (P < 0.01). (2) After 12 hours of culture, the adherence of bone marrow mesenchymal stem cells on the two scaffolds was similar, 83% and 81% cells adhered on the traditional and fluffy scaffolds, respectively. (3) After 7 days of culture, the number of proliferated cells in the fluffy hydroxyapatite/polylactic acid composite scaffold was significantly more than that in the traditional hydroxyapatite/polylactic acid composite scaffold (P < 0.01). (4) After 7 days of culture, FDA staining and scanning electric microscopy showed that cell-cell independent shape appeared in the traditional scaffold. A large number of cells appeared in the fluffy scaffold and grew into cell clusters with high cell activity, which formed a cell-fiber construction. These results indicate that this new type hydroxyapatite/polylactic acid composite scaffold is beneficial for cell entry and proliferation.
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There is inherent rise of pesticide poisoning in India. Among all these pesticide indoxacarb is registered for use to control lepidopteran insects on crops, turf grasses, and landscape ornamentals. A novel chromatographic reagent is described for detection and identifications of Indoxacarb by HPTLC by use of furfural reagent. Indoxacarb (I) on acid hydrolysis yield its metabolites namely 4-trifloro-methoxy-phenyl amine (II), Oxidiazine (III) and acetic acid (IV). The 4-trifloro-methoxy-phenyl amine (II) under acidic condition reacts with furfural which gives grayish black colored spot on heating. The constituents of viscera (amino, acids, peptides, proteins, etc.) and plant materials do not interfere with the test. The detection limit for Indoxacarb is 0.5?g. The reaction mechanism is discussed. The necessary HPTLC parameter like concentration of analyte also mentioned for the efficient detection of indoxacarb pesticide.
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From December 2011 to August 2017,56 patients with acute abdomen surgery were treated in Affiliated Zhongshan Hospital of Dalian University.The anatomical structure of ileocecal Treves folds was observed during operation,and 15 samples of Treves folds were taken for histological examination.The mean length of the fold was (5.56±0.18)cm for males and (5.22±0.05)cm for female,the width was (1.82± 0.04) cm for males and (1.78 ± 0.06) cm for females;the thickness was (0.18 ± 0.02) cm.HE and verhoeff staining showed that Treves fold was mainly composed of elastic fiber,collagen fiber and smooth muscle with abundant blood supply.Thirty patients were repaired with their own Treves folds,including the fixation with overlay suture to the stump of appendectomy in 26 cases,repairing for perforation of colonic diverticulum in 3 case,and repairing for perforation of colonic diverticulum in 1 case.There were no complications such as fecal fistula,intestinal obstruction and intussusception after operation.The Treves fold has a constant location,which can be used as a clear sign of ileal terminal.It has abundant blood supply,and is suitable for the repair and reconstruction in ileocecal operation.
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Objective: To investigate the mechanical properties of the novel compound calcium phosphate cement (CPC) biological material as well as the biological activity and osteogenesis effects of induced pluripotent stem cells (iPS) seeding on scaffold and compare their bone regeneration efficacy in cranial defects in rats. Methods: Ac- cording to the different scaffold materials, the experiment was divided into 4 groups: pure CPC scaffold group (group A), CPC∶10% wt chitosan as 2∶1 ratio mixed scaffold group (group B), CPC∶10% wt chitosan∶whisker as 2∶1∶1 ratio mixed scaffold group (group C), and CPC∶10% wt chitosan∶whisker as 2∶1∶2 ratio mixed scaffold group (group D). Mechanical properties (bending strength, work-of-fracture, hardness, and modulus of elasticity) of each scaffold were detected. The scaffolds were cultured with fifth generation iPS-mesenchymal stem cells (MSCs), and the absorbance ( A) values of each group were detected at 1, 3, 7, and 14 days by cell counting kit 8 (CCK-8) method; the alkaline phosphatase (ALP) activity, Live/Dead fluorescence staining and quantitative detection, ALP, Runx2, collagen typeⅠ, osteocalcin (OC), and bone morphogenetic protein 2 (BMP-2) gene expressions by RT-PCR were detected at 1, 7, and 14 days; and the alizarin red staining were detected at 1, 7, 14, and 21 days. Twenty-four 3-month-old male Sprague Dawley rats were used to establish the 8 mm-long skull bone defect model, and were randomly divided into 4 groups ( n=6); 4 kinds of scaffold materials were implanted respectively. After 8 weeks, HE staining was used to observe the repair of bone defects and to detect the percentage of new bone volume and the density of neovascularization. Results: The bending strength, work-of-fracture, hardness, and modulus of elasticity in groups B, C, and D were significantly higher than those in group A, and in groups C, D than in group B, and in group D than in group C ( P0.05). Live/Dead fluorescence staining showed that the proportion of living cells in groups B, C, and D at 7 and 14 days was significantly higher than that in group A ( P0.05). RT-PCR showed that the relative expressions of genes in groups B, C, and D at 7 and 14 days were significantly higher than those in group A, and in groups C, D than in group B ( P0.05). Alizarin red staining showed that the red calcium deposition on the surface of scaffolds gradually deepened and thickened with the prolongation of culture time; the A values in groups B, C, and D at 14 and 21 days were significantly higher than those in group A ( P0.05). In vivo repair experiments in animals showed that the new bone in each group was mainly filled with the space of scaffold material. Osteoblasts and neovascularization were surrounded by new bone tissue in the matrix, and osteoblasts were arranged on the new bone boundary. The new bone in groups B, C, and D increased significantly when compared with group A, and the new bone in groups C and D was significantly higher than that in group B. The percentage of new bone volume and the density of neovascularization in groups B, C, and D were significantly higher than those in group A, and in groups C and D than in group B ( P0.05). Conclusion: The mechanical properties of the new reinforced composite scaffold made from composite chitosan, whisker, and CPC are obviously better than that of pure CPC scaffold material, which can meet the mechanical properties of cortical bone and cancellous bone. iPS-MSCs is attaching and proliferating on the new reinforced composite scaffold material, and the repair effect of bone tissue is good. It can meet the biological and osteogenic activity requirements of the implant materials in the bone defect repair.
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Objectives: to describe the knowledge of nursing teachers of a nursing course on Norm 32 and on postexposure practices to biological materials and to identify the vaccination status of these teachers. Method: Quantitative descriptive cross-sectional study. Data was collected between September and October 2014, using a questionnaire and analyzed using the SPSS statistical software 21.0. The participants were 35 nursing teachers. Results: 71.4% were female; 100% claimed to have knowledge on biosecurity; 51.4% knew Norm 32; 71.4% were immunized for hepatitis B; 22.9% had accidents involving biological material; only 14.3% cited washing the injury with water and soap after the occurrence of an accident. Conclusion: It was evidenced that there is a weakness in the teachers knowledge regarding biosafety actions.
Objetivos: descrever o conhecimento dos docentes enfermeiros de um curso de enfermagem sobre Norma Regulamentadora 32 e as condutas pósexposição a materiais biológicos e identificar a situação vacinal destes docentes. Método: Estudo quantitativo descritivo de corte transversal. Os dados foram coletados, entre setembro e outubro de 2014, através de um questionário, e analisados através do Software estatístico SPSS 21.0. Participaram da pesquisa35 docentes enfermeiros. Resultados: 71,4% eram do sexo feminino; 100% afirmou ter conhecimento sobre biossegurança; 51,4% conheciam a Norma Regulamentadora 32; 71,4% estavam imunizados para hepatite B; 22,9% sofreram acidente envolvendo material biológico; apenas 14,3% citaram a lavagem com água e sabão do ferimento após a ocorrência de acidente. Conclusão: Evidenciou-se que existe uma fragilidade no conhecimento dos docentes relativo às ações de biossegurança.
Objetivos: describir el conocimiento de los profesores de enfermería de un curso de enfermería en la Norma 32 y comportamientos posterior a la exposición a materiales biológicos y para identificar el estado de vacunación de estos maestros. Método: Estudio descriptivo transversal cuantitativo. Los datos fueron recogidos entre septiembre y octubre de 2014, mediante un cuestionario y analizados mediante el programa estadístico SPSS 21.0. Los participantes fueron 35 profesores de enfermería. Resultados: 71,4% eran mujeres; 100% afirmó tener conocimiento de la bioseguridad; 51,4% conocía la Norma 32; 71,4% fueron inmunizados contra la hepatitis B; 22,9% tenían accidentes con material biológico; sólo el 14,3% citó lavado con agua y jabón lesión ante la ocurrencia de un accidente. Conclusión: Se demostró que hay una debilidad en el conocimiento de los profesores en relación con las acciones de bioseguridad.
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Humans , Faculty, Nursing , /prevention & control , Occupational Risks , Occupational Health , BrazilABSTRACT
Introducción: el trabajo con microorganismos puede conllevar a riesgos tanto para el personal que trabaja con los mismos como para el medio ambiente. La existencia de laboratorios de seguridad biológica y la implementación de medidas en la manipulación de los agentes biológicos minimizan el riesgo. Objetivo: evaluar las medidas de bioseguridad adoptadas en el manejo con materiales biológicos en Laboratorios Liorad. Métodos: empleo de una lista de chequeo y análisis de los resultados a través de una Matriz DAFO para valorar si el diseño de la instalación cumple con la bioseguridad. Además establecer un sistema documental para la manipulación de microorganismos y la confección de un plan de capacitación para el personal que trabaja en el laboratorio de control microbiológico. Resultados: la lista de chequeo permitió identificar como principal debilidad el no disponer de un doble pasillo para el traslado del material limpio y sucio. Como fortalezas, cumplir con las prácticas y procesamientos adecuados y el contar con equipos de seguridad biológica. El sistema documental incorporó a los procedimientos establecidos para la manipulación, un acápite referido a la Peligrosidad y Medidas de Seguridad. El programa de capacitación desarrollado permitió proveer conocimientos específicos referidos a esta temática. Conclusión: las medidas adoptadas en el laboratorio permiten plantear que de manera general se cumplen los requisitos establecidos en materia de Bioseguridad para el trabajo con microorganismos
Introduction: working with microorganisms can lead to risks for both the staff at work and the environment. The existence of biosafety labs and implementation of measures in the handling of biological agents minimize the risk. Objetive: to evaluate biosecurity measures taken in handling biological materials at Liorad Laboratories. Methods: using a checklist and analysis of results through a SWOT Matrix to assess whether the design of the facility complies with biosafety or not. A documented system for handling of microorganisms and the preparation of a training plan for staff working in the laboratory of microbiological control. Results: the checklist identified as the main weakness the absence of a double corridor for the transfer of clean and dirty equipment, and as strength, meeting processing practices and have adequate biosafety equipment. The documentation system incorporated a section related to Threat and Safety Measures into the handling procedure. The training program developed allowed providing specific knowledge about this topic. Conclusion: it was concluded that the measures taken in the laboratory facilitated the overall fulfillment of the biosafety requirements for working with microorganisms
Subject(s)
LaboratoriesABSTRACT
Objective To explore the mechanical testing technique suitable for biological materials under water environment. Methods Based on digital image correlation (DIC) method, the unique lens sleeves which can avoid the distortion caused by underwater photography was designed, and this technique was applied to determining mechanical properties of the fish scales. Results The experiment on translation of the water sink indicated that the use of the designed lens sleeves could effectively reduce errors for underwater measurement with high precision; the mechanical testing on fish scales showed that different regions of the fish scales had obviously different mechanical properties, but the differences induced by regions of the dehydrated fish scales were significantly reduced. Conclusions The designed lens sleeves in this study can be applied to image acquisition effectively, and determination of mechanical properties of the biological materials under water environment was achieved using DIC method.
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Researches on mechanical properties of biological hard tissues are of great importance to the prevention and treatment for both bone diseases and oral diseases. Meanwhile, biological materials possess superior mechanical properties due to long-term evolution, and studies on the structure and mechanical properties of these materials can provide useful solutions for the design of engineering materials. However, unlike engineering materials, mechanical studies on biological materials need specific methods to accurately characterize the mechanical performance. This paper summarized the research methods on mechanical properties of biological hard tissues, including routine mechanical tests, fracture mechanics tests, nanoindentation tests, as well as numerical simulation techniques in nano, micro and macro scales.
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Objective To study mechanical properties of the microstructure of the articular cartilage with biological activity by nanoindentation tests under the condition of keeping the articular cartilage in water. Methods The different abilities to keep in situ mechanical properties of the articular cartilage with cold mosaic method or with moisturizing method were evaluated by experiments, and the mechanical properties of the microstructure of the articular cartilage in different kinds of solution used in moisturizing method were also obtained. Results The experiment showed that the elastic modulus on the cartilage surface layer with cold mosaic method was much higher than that with moisturizing method, and the elastic modulus on the cartilage surface and deep layer in chitosan and saline were much lower than that in distilled water. Conclusions The moisturizing method is better at preserving in situ mechanical properties and biological activity of the biological materials, and chitosan and saline are proved to have the effect of keeping mechanical properties of the cartilage used in moisturizing method.
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As a rapidly developing area in biomechanics, mechanics of biological materials aims to investigate the fundamental relationship between functions, properties, structures, and compositions of various natural biological materials at different length scales and the underlying physical mechanisms through experimental research and theoretical analysis, and to provide inspirations from the splendid living world for the biomimetic design of new materials. In this paper, some recent achievements, mainly made by Chinese scholars in this field, are briefly reviewed, including the stiffening and toughening mechanisms of such biological composites as nacres and horns, the relation between the surface wetting behavior and the micro/nanostructures, and some relevant biomimetic applications as well. The contents of seven invited papers published in this special issue are also introduced.
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A rapid, simple, sensitive and selective spectrophotometric method has been developed for the determination of Palladium (II) using newly synthesized reagent 4-Hdroxy3,5dimethoxybenzaldehyde-4- hydroxybenzoylhydrazone (HDMBHBH) in neutral surfactant of TritonX-100-5% (micellar medium). Palladium (II) forms a brown coluored water-soluble complex with 4-Hdroxy 3, 5dimethoxybenzaldehyde-4- hydroxybenzoylhydrazone in the pH range 1.0-6.0. The complex shows maximum absorbance at lmax 373 nm and in the pH range 3.0-4.0. However, at this wavelength, the reagent shows considerable absorbance. At lmax 373 nm, the complex shows maximum absorbance while the reagent blank shows negligible absorbance. Hence, analytical studies are carried out at lmax 373 nm and at pH 3.0 (Phosphate buffer) against reagent blank. Beer's law is obeyed in the range 0.106-1.064 μg ml-1 and the optimum concentration range from ringbom plot is 0.212-0.957 mg/ml of Palladium (II). The molar absorptivity and Sandell's sensitivity for the coloured solution are found to be 7.5 x 104L mol-1 cm-1 and 0.0015-μg. cm-2 respectively. The interference effect of various diverse ions has been studied. The complex shows 1:1 [Pd (II): HDMBHBH] stoichiometry with stability constant 7.29 x 106. The standard deviation of the method in the determination of 0.638 - μg ml-1 of Palladium (II) is 0.003 and the Relative standard deviation is 0.71%. First and second order derivative spectroscopic method is developed at lmax 422 nm and lmax 444 nm respectively for the determination of Palladium (II), which is more sensitive than the zero order method. The developed method has been employed for the determination of Palladium (II) in hydrogenation catalyst samples and in synthetic alloy samples. The results are in good agreement with the certified values.
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This cohort study is a collaborative effort of 8 institutions. The goal is to establish a large scale cohort that can be followed for 10 or more years to assess the relationship between life-styles and cancer occurrence, and to evaluate the role of environmental exposures in the development of six major sites of cancers(stomach, liver, lung, colorectum, uterine cervix and female breast) in the rural population. Since 1993, 11,304 men and women aged over 35 living in four areas have been recruited. The number of target population is 30,000 persons, which is expected to be successfully recruited until 1999. Each subject has completed a detailed questionnaire on general life-styles, reproductive factors, and agricultural chemical exposures through the interview. Anthropometric measurements with body fat composition and the routine clinical laboratories were examined. For the cancer-free cohort, physical examination by the physicians and serologic tests for hepatitis markers, some tumor markers, and lipid profile have been done, but not all. In order to provide an opportunity to incorporate barious biomarkers of exposure and effect as well as genetic susceptibility, a biologic tissue bank has been established from blood and urine sample(plasma, WBC buffy-coat, RBC clots, and urine supernatant) stored at-70degrees C. Re-examination of changes in exposere to risk factors will be done periodically. Disease occurrence will be ascertained by the active(mainly through diagnosis by physicians) and the passive surveillance(through both death certificate and screening of medical utilization records).