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1.
Feed quality, feed characteristics, nutrient utilization and digestive behaviour are closely related to: (i) total feed composition, (ii) feed intrinsic structures, and (iii) biological component matrix (such as protein to starch matrix, protein to carbohydrate matrix). Conventional "wet" chemical analysis can determine total chemical composition, but fails to detect the feed intrinsic structures and biological component matrix due to destruction of feed samples during the processing for chemical analysis and the "wet" chemical analysis cannot link structural information to chemical information within intact feed tissue. Recently, advanced synchrotron-based Fourier transform infrared (FTIR) microspectroscopy has been developed as a non-destructive and non-invasive structural-chemical analytical technique. This technique can link chemical information to structural information of biological samples within intact tissue within cellular dimensions. It can provide four kinds of information simultaneously: tissue composition, tissue structure, tissue chemistry and tissue environment. However, this novel technique has been found mainly for medical science research, extremely rare for feed science and nutrition research. The objective of this review article was to illustrate synchrotron-based FTIR microspectroscopy as a novel research tool for rapid characterization of feed structures at a cellular level and for detection of chemical features and molecular chemical make-up of feed biological component matrix and nutrient interaction. The emphasis of this article was to show that feed structural-chemical features at a cellular level are closely related to feed characteristics, feed quality and nutritive value in animals. The synchrotron-based technology will provide us with a greater understanding of the plant-animal interface.  相似文献   

2.
This article describes a set of procedures for developing tissue, water, and sediment quality guidelines for the protection of aquatic life by using the tissue-residue approach (TRA) for toxicity assessment. The TRA, which includes aspects of the Critical Body Residue (CBR) approach, associates tissue concentrations of chemicals with adverse biological effects in a dose-response fashion that can be used to determine CBRs. These CBRs can then be used to develop tissue quality guidelines (TQGs), which may be translated into water or sediment guidelines with bioaccumulation factors. Not all toxicants are amenable to this type of analysis; however, some appear to exhibit relatively consistent results that can likely be applied in a regulatory framework. By examining tissue residues, variations in toxicokinetics (temporal aspects of accumulation, biotransformation, and internal distribution) are greatly reduced allowing a greater focus on toxicodynamics (action and potency) of the toxicants. The strongest feature of this approach is causality; hence, guidelines based on tissue concentrations are based on data demonstrating a causal relationship between the acquired dose and the biological effect. Because the TRA has utility for assessing the toxicity of contaminant mixtures, an approach is presented here using toxic unit values that can be used to assess the likelihood of observing toxic effects based on tissue residues.  相似文献   

3.
Many biological systems experience a periodic environment. Floquet theory is a mathematical tool to deal with such time periodic systems. It is not often applied in biology, because linkage between the mathematics and the biology is not available. To create this linkage, we derive the Floquet theory for natural systems. We construct a framework, where the rotation of the Earth is causing the periodicity. Within this framework the angular momentum operator is introduced to describe the Earth’s rotation. The Fourier operators and the Fourier states are defined to link the rotation to the biological system. Using these operators, the biological system can be transformed into a rotating frame in which the environment becomes static. In this rotating frame the Floquet solution can be derived. Two examples demonstrate how to apply this natural framework.  相似文献   

4.
Background: The current study presents a fully planar wireless power transfer (WPT) scheme with the aim of providing enough power for capsule endoscopy performance. The method’s implementation on patients is more convenient than that of the previous conventional WPT plans in which a cylindrical wire coil is placed around the patient’s body. In addition to this, while using the present printed power receiver structure, the capsule’s internal space of opens up for other components such as the image sensors and data transmitting components. To improve the efficiency, a two-layer printed coil has been used as the transmitter, a two-layer printed coil as the receiver and a power coil on the transmitter side excited at 13.56 MHz.Results: Applying this method, the efficiency has increased to more than 2% for the proposed structure. Moreover, the effect of the body tissue on power efficiency has been simulated and measured and the maximum specific absorption rate (SAR) value considered for the desired system. Conclusions: The obtained results indicate that the proposed system meets the medical standards requirements.  相似文献   

5.
Sectioning of tissue specimens of aligned cells (e.g., muscle, cochlea, retina) for micrographs, often requires the capsule containing the tissue to be positioned at a precise angle during sectioning. The correct angle can be set by trial and error, but the process can be shortened if the gross anatomy of the cell system is used as a guide to orient the embedded sections as closely as possible in the optimal plane. Thick sections are then cut in this plane with a razor blade, and these sections are re-embedded in preparation for thin sectioning. This technique eliminates the large angles of the capsule in the microtome which occur when the gross tissue is poorly aligned in the first embedding.  相似文献   

6.
A series of recently published studies have established that defects in endocytic sorting can elicit dramatic tissue overgrowth phenotypes in developing organs of the fruit fly Drosophila melanogaster. Such a link had been suggested by mammalian cell culture experiments almost ten years ago, but in vivo evidence of this link, and the mechanisms through which it might occur, had remained elusive. Drosophila has now proven to be an excellent developmental system in which to document the effects of endocytic defects on tissue growth, and to probe the basis of these phenotypes. This work has begun to illuminate some surprising connections between the endocytic trafficking of protein cargoes and the control of cell proliferation and tissue architecture. These connections touch major cell biological processes, including cell division, growth, death, and polarity, and have begun to paint a complex yet intriguing picture of how defective endocytic sorting can effect developing tissues.  相似文献   

7.
低强度激光的生物效应对组织修复的影响   总被引:3,自引:0,他引:3  
本文概述了近几年低强度激光照射疗法对促进骨骼肌的再生、关节炎与骨折的修复、改善心肌微循环等方面生物效应的实验研究的新进展,其结果表明低强度激光照射组织具有显著的生物刺激作用和损伤后的修复功能。  相似文献   

8.
The acceptable power range technique previously described in a companion paper [R. B. Roemer, T. C. Cetas, J. R. Oleson, S. Halac, and A. Y. Matloubieh, Radiat. Res. 100, 450-472 (1984)] is applied to two heating modalities to demonstrate its application to simulated clinical situations. Comparisons of the abilities of the different modalities to heat given tumors are made using the relative sizes of the acceptable power ranges obtained for each modality. Similar comparisons are also possible for determining the efficacy of physiological manipulations and adjustments in power deposition patterns for a given heating modality. Predictions of the ability of modalities and configurations to properly heat tumors are made using the bracketing nature of the uniform and annular tumor perfusion models. These comparisons and predictions are possible because a single measure of the ability of any heating technique to heat an arbitrary tumor in any location is utilized (the size of the acceptable power range). While relatively simple models are presently utilized, this approach can be extended to take into account a host of physical and biological conditions that model the patient-device interaction to an arbitrarily high degree of detail. These refinements will be based on extended clinical and experimental data, particularly as tumor and normal tissue blood perfusion characteristics either become better known in general cases or can be specified for each real tumor. The applications of this approach should be far-reaching and complementary to clinical hyperthermia, especially as further model refinements are incorporated. Additional data are presented which reinforce the bracketing nature of the uniform and annular tumor perfusion models presented in the companion paper.  相似文献   

9.
The glenohumeral joint is the most frequently dislocated major joint in the body, and instability due to permanent deformation of the glenohumeral capsule is a common pathology. The corresponding change in mechanical properties may have implications for the ideal location and extent of plication, which is a common clinical procedure used to repair the capsule. Therefore, the objective of this study was to quantify the mechanical properties of four regions of the glenohumeral capsule after anterior dislocation and compare the properties to the normal glenohumeral capsule. Six fresh-frozen cadaveric shoulders were dislocated in the anterior direction with the joint in the apprehension position using a robotic testing system. After dislocation, mechanical testing was performed on the injured glenohumeral capsule by loading the tissue samples in tension and shear. An inverse finite element optimization routine was used to simulate the experiments and obtain material coefficients for each tissue sample. Cauchy stress–stretch curves were then generated to represent the mechanical response of each tissue sample to theoretical loading conditions. Based on several comparisons (average of the material coefficients, average stress–stretch curve for each region, and coefficients representing the average curves) between the normal and injured tissue samples, the mechanical properties of the injured tissue samples from multiple regions were found to be lower than those of the normal tissue in tension but not in shear. This finding indicates that anterior dislocation primarily affects the tensile behavior of the glenohumeral capsule rather than the shear behavior, and this phenomenon could be caused by plastic deformation of the matrix, permanent collagen fiber rotation, and/or collagen fiber failure. These results suggest that plication and suturing may not be sufficient to return stability to the shoulder after dislocation in all individuals. Thus, surgeons may need to perform a procedure that reinforces or stiffens the tissue itself, such as reconstruction or augmentation, to improve repair procedures.  相似文献   

10.
Acar E  Plopper GE  Yener B 《PloS one》2012,7(3):e32227
The structure/function relationship is fundamental to our understanding of biological systems at all levels, and drives most, if not all, techniques for detecting, diagnosing, and treating disease. However, at the tissue level of biological complexity we encounter a gap in the structure/function relationship: having accumulated an extraordinary amount of detailed information about biological tissues at the cellular and subcellular level, we cannot assemble it in a way that explains the correspondingly complex biological functions these structures perform. To help close this information gap we define here several quantitative temperospatial features that link tissue structure to its corresponding biological function. Both histological images of human tissue samples and fluorescence images of three-dimensional cultures of human cells are used to compare the accuracy of in vitro culture models with their corresponding human tissues. To the best of our knowledge, there is no prior work on a quantitative comparison of histology and in vitro samples. Features are calculated from graph theoretical representations of tissue structures and the data are analyzed in the form of matrices and higher-order tensors using matrix and tensor factorization methods, with a goal of differentiating between cancerous and healthy states of brain, breast, and bone tissues. We also show that our techniques can differentiate between the structural organization of native tissues and their corresponding in vitro engineered cell culture models.  相似文献   

11.
The ocular lens capsule is a smooth, transparent basement membrane that encapsulates the lens and is composed of a rigid network of interacting structural proteins and glycosaminoglycans. During cataract surgery, the anterior lens capsule is routinely removed in the form of a circular disk. We considered that the excised capsule could be easily prepared for matrix-assisted laser desorption/ionization time-of-flight mass spectrometry imaging (MALDI-MSI) analysis. MALDI-MSI is a powerful tool to elucidate the spatial distribution of small molecules, peptides, and proteins within tissues. Here, we apply this molecular imaging technique to analyze the freshly excised human lens capsule en face. We demonstrate that novel information about the distribution of proteins by MALDI-MSI can be obtained from this highly compact connective tissue, having no evident histo-morphological characteristics. Trypsin digestion carried out on-tissue is shown to improve MALDI-MSI analysis of human lens capsules and affords high repeatability. Most importantly, MALDI-MSI analysis reveals a concentric distribution pattern of proteins such as apolipoprotein E (ApoE) and collagen IV alpha-1 on the anterior surface of surgically removed lens capsule, which may indicate direct or indirect effects of environmental and mechanical stresses on the human ocular lens.  相似文献   

12.
The cartilaginous articular surface of the distal part of the femur of adult dogs was removed and the composition of GAGs was determined in the granulation tissue adhering to the bone wound and in that adhering to the articular capsule 7, 33, and 70 days after operation. The articular cartilage and the synovial layer of the articular capsule of intact adult dogs were also studies. The materials were digested with papain and the released GAGs were fractionated according to Svejcar and Robertson's method. The articular cartilage of non-operated dogs contained, on the average, 65.3% ChS, 13% KS, 5.8% HA and 15.8% GAG of lower molecular weight. The synovial layer of the capsule contained 41.1% HA, 15.3% Ch4-S and Ch6-S, 13.7% DS, 21.7% KS, 2% H and 6% GAG of lower molecular weight. The granulation tissue of the articular surface and that adhering to the capsule show a different developmental course. The former differentiates into cartilage, whereas the latter is simply added to the tissue of the capsule. The two tissues are different in GAG composition as early as on the 7th postoperative day. With time an increase of Ch4-S, Ch6-S and KS can be observed in the tissue of the articular surface. The tissue adhering to the capsule is characterized by a high HA and an increasing DS content. From the study of the composition of GAG's (proportion of GAG building stones) a deeper insight can be obtained into the details of GAG biosynthesis characteristic of cartilage than from the analysis of quantitative data of ChS. In the development of GAG composition characteristic of the tissue, the epimerase reactions participating in GAG biosynthesis, and the mechanisms regulating their activities seem to play a primary role.  相似文献   

13.
Molecular profiling of human biopsies and surgical specimens is frequently complicated by their inherent biological heterogeneity and by the need to conserve tissue for clinical diagnosis. We have developed a set of novel 'tissue print' and 'print-phoresis' technologies to facilitate tissue and tumor-marker profiling under these circumstances. Tissue printing transfers cells and extracellular matrix components from a tissue surface onto nitrocellulose membranes, generating a two-dimensional anatomical image on which molecular markers can be visualized by specific protein and RNA- and DNA-detection techniques. Print-phoresis is a complementary new electrophoresis method in which thin strips from the print are subjected to polyacrylamide gel electrophoresis, providing a straightforward interface between the tissue-print image and gel-based proteomic techniques. Here we have utilized these technologies to identify and characterize markers of tumor invasion of the prostate capsule, an event generally not apparent to the naked eye that may result in tumor at the surgical margins ('positive margins'). We have also shown that tissue-print technologies can provide a general platform for the generation of marker maps that can be superimposed directly onto histopathological and radiological images, permitting molecular identification and classification of individual malignant lesions.  相似文献   

14.

Background  

Gastrointestinal (GI) endoscopy has been popularly applied for the diagnosis of diseases of the alimentary canal including Crohn's Disease, Celiac disease and other malabsorption disorders, benign and malignant tumors of the small intestine, vascular disorders and medication related small bowel injury. The wireless capsule endoscope has been successfully utilized to diagnose diseases of the small intestine and alleviate the discomfort and pain of patients. However, the resolution of demosaicked image is still low, and some interesting spots may be unintentionally omitted. Especially, the images will be severely distorted when physicians zoom images in for detailed diagnosis. Increasing resolution may cause significant power consumption in RF transmitter; hence, image compression is necessary for saving the power dissipation of RF transmitter. To overcome this drawback, we have been developing a new capsule endoscope, called GICam.  相似文献   

15.
The glenohumeral joint is frequently dislocated resulting in injury to the glenohumeral capsule. Repair techniques that focus on restoring the capsule after dislocation to re-establish its stabilizing function could benefit from predictions of the location of failure in this continuous sheet of tissue with a random collagen fiber alignment in the unloaded state. Therefore, the objective of this study was to determine the collagen fiber alignment and maximum principal strain in all regions of the capsule during uniaxial extension to failure and to determine whether these parameters could predict the location of tissue failure. Collagen fiber alignment, quantified using a small-angle light-scattering device, and maximum principal strain in the capsule were determined at 5 % increments of elongation until tissue failure. A contingency table analyzed with Fischer’s exact test demonstrated that peak collagen fiber alignment, represented by the normalized orientation index ( $p < 0.001$ ) and maximum principal strain ( $p < 0.001$ ), is significant in predicting location of failure. The direct correlation between the maximum principal strain and collagen fiber alignment measured prior to failure to the location of tissue failure suggests these parameters can be used as a predictive tool to help locate the areas of the glenohumeral capsule that are susceptible to failure. In the future, changes in collagen fiber alignment following injury could be used to develop a constitutive model for injured capsular tissue.  相似文献   

16.
Nick translation is used to label DNA and RNA to produce probes for in situ hybridization and Northern and Southern blotting. Fluorescence in situ hybridization (FISH) is a widely applied technique used to determine chromosomal and genetic anomalies in many biological samples. Initially the technique was applied to metaphase preparations, but the usefulness of detecting genetic anomalies in solid tumors in situ has resulted in the development of modified protocols. Formalin fixed paraffin processed tissue sections present novel challenges when applying FISH; the probes must be small (between 200 and 600 base pairs) and pretreatment is necessary before the probes can be applied to tissue sections, to promote probe access to target DNA. Here we report on a modification of a nick translation method to produce a probe that can reliably be used with FISH in paraffin processed tissue sections.  相似文献   

17.
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19.
Diarthrodial joints are freely moveable joints containing synovial fluid (SF) within a connective tissue joint capsule that allows for low-friction and low-wear articulation of the cartilaginous ends of long bones. Biomechanical cues from joint articulation regulate synoviocyte and cartilage biology via joint capsule strain, in turn altering the composition of SF. Joint flexion is clinically associated with pain in knees with arthritis and effusion, with the nociception possibly originating from joint capsule strain. The hypothesis of this study was that knee fluid volume distribution and joint capsule strain are altered with passive flexion in the rabbit model. The aims were to (a) determine the volume distribution of fluid in the joint at different total volumes and with flexion of rabbit knees ex vivo, (b) correlate the volume distribution for the ex vivo model to in vivo data, and (c) determine the strains at different locations in the joint capsule with flexion. During knee flexion, ~20% of anteriorly located joint fluid moved posteriorly, correlating well with the fluid motion observed in in vivo joints. Planar joint capsule principal strains were ~100% (tension) in the proximal-distal direction and ~-40% (shortening) in the circumferential direction, relative to the femur axis and 30° strain state. The joint capsule strains with flexion are consistent with the mechanics of the tendons and ligaments from which the capsule tissue is derived. The movement and mixing of SF volume with flexion determine the mechanical and biological fluid environment within the knee joint. Joint fluid movement and capsular strains affect synovial cell biology and likely modulate trans-synovial transport.  相似文献   

20.
The goal of this protocol is to build a parallel high-extinction and high-resolution optical Brillouin spectrometer. Brillouin spectroscopy is a non-contact measurement method that can be used to obtain direct readouts of viscoelastic material properties. It has been a useful tool in material characterization, structural monitoring and environmental sensing. In the past, Brillouin spectroscopy has usually employed scanning Fabry-Perot etalons to perform spectral analysis. This process requires high illumination power and long acquisition times, making the technique unsuitable for biomedical applications. A recently introduced novel spectrometer overcomes this challenge by employing two VIPAs in a cross-axis configuration. This innovation enables sub-Gigahertz (GHz) resolution spectral analysis with sub-second acquisition time and illumination power within the safety limits of biological tissue. The multiple new applications facilitated by this improvement are currently being explored in biological research and clinical application.  相似文献   

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