231,759 research outputs found
Software for full-color 3D reconstruction of the biological tissues internal structure
A software for processing sets of full-color images of biological tissue
histological sections is developed. We used histological sections obtained by
the method of high-precision layer-by-layer grinding of frozen biological
tissues. The software allows restoring the image of the tissue for an arbitrary
cross-section of the tissue sample. Thus, our method is designed to create a
full-color 3D reconstruction of the biological tissue structure. The resolution
of 3D reconstruction is determined by the quality of the initial histological
sections. The newly developed technology available to us provides a resolution
of up to 5 - 10 {\mu}m in three dimensions.Comment: 11 pages, 8 figure
The Current Use of Stem Cells in Bladder Tissue Regeneration and Bioengineering.
Many pathological processes including neurogenic bladder and malignancy necessitate bladder reconstruction, which is currently performed using intestinal tissue. The use of intestinal tissue, however, subjects patients to metabolic abnormalities, bladder stones, and other long-term sequelae, raising the need for a source of safe and reliable bladder tissue. Advancements in stem cell biology have catapulted stem cells to the center of many current tissue regeneration and bioengineering strategies. This review presents the recent advancements in the use of stem cells in bladder tissue bioengineering
Separating Overlapping Tissue Layers from Microscopy Images
Manual preparation of tissue slices for microscopy imaging can introduce
tissue tears and overlaps. Typically, further digital processing algorithms
such as registration and 3D reconstruction from tissue image stacks cannot
handle images with tissue tear/overlap artifacts, and so such images are
usually discarded. In this paper, we propose an imaging model and an algorithm
to digitally separate overlapping tissue data of mouse brain images into two
layers. We show the correctness of our model and the algorithm by comparing our
results with the ground truth
Reconstruction of maxillofacial bone defects: Contemporary methods and future techniques
Reconstruction of maxillofacial continuity defects has always
been a challenging tasks for the scientist and surgeons over the
years. The main goal of the reconstruction of the maxillofacial
region is to restore facial form, function, full rehabilitation of
occlusion and articulation. A refinement in surgical technique
and methods of reconstruction has improved patient’s quality of
life. This manuscript reviewed exciting methods of bone
reconstruction and confirms that the ideal system for
reconstruction of critical size continuity defect of the jaw bones
has yet to be found. Shortcoming and limitation of each method
has been discussed. The author highlight recent advances on
how tissue engineering which could offer biological substitute to
restore, maintain, or improve oro-facial function
Terminal Sterilization of Anterior Cruciate Ligament (ACL) Allografts: A Systematic Review of Outcomes
Introduction. Anterior cruciate ligament (ACL) injuries are common and reconstruction can be completed with either autograft or allograft tissue. However, there is concern about an increased failure rate with allograft tissue. The purpose of this study was to systematically review the available evidence to determine the effect of irradiation and level of dose on the failure rates of allograft in ACL reconstruction.
Methods. A literature search was performed using PubMed, Scopus, and Web of Science from January 2000 to September 2013. Inclusion criteria consisted of the following: (1) primary, unilateral, single-bundle allograft ACL procedure, (2) studies with data documenting graft type and terminal sterilization technique, (3) subjective assessments of outcome, and (4) objective assessments of outcome. Studies without reported subjective and objective outcomes and those pertaining to revision ACL reconstruction were excluded. Failures were defined and compared between irradiated and non-irradiated grafts, as well as between grafts irradiated with 1.2 - 1.8 Mrad and those with 2.0 - 2.5 Mrad.
Results. Of the 242 articles identified via initial search, 17 studies met the final inclusion criteria. A total of 1,090 patients were evaluated in this study, all having undergone unilateral primary ACL reconstruction with allograft tissue with 155 failures. The failure rate between non-irradiated (98/687, 14.7%) and irradiated (57/408, 14.0%) was not statistically significant (p = 0.86). Grafts in the high-dose irradiation group (27/135, 20.0%) had a statistically significant higher (p < 0.001) rate of failure than those in the low-dose irradiation group (30/273, 10.6%).
Conclusion. The irradiation of an allograft increases the risk of failure after an ACL reconstruction but the use of lower doses of radiation decreases that risk
Altered brain energetics induces mitochondrial fission arrest in Alzheimer's Disease.
Altered brain metabolism is associated with progression of Alzheimer's Disease (AD). Mitochondria respond to bioenergetic changes by continuous fission and fusion. To account for three dimensional architecture of the brain tissue and organelles, we applied 3-dimensional electron microscopy (3D EM) reconstruction to visualize mitochondrial structure in the brain tissue from patients and mouse models of AD. We identified a previously unknown mitochondrial fission arrest phenotype that results in elongated interconnected organelles, "mitochondria-on-a-string" (MOAS). Our data suggest that MOAS formation may occur at the final stages of fission process and was not associated with altered translocation of activated dynamin related protein 1 (Drp1) to mitochondria but with reduced GTPase activity. Since MOAS formation was also observed in the brain tissue of wild-type mice in response to hypoxia or during chronological aging, fission arrest may represent fundamental compensatory adaptation to bioenergetic stress providing protection against mitophagy that may preserve residual mitochondrial function. The discovery of novel mitochondrial phenotype that occurs in the brain tissue in response to energetic stress accurately detected only using 3D EM reconstruction argues for a major role of mitochondrial dynamics in regulating neuronal survival
Reconstruction of heel soft tissue defects using sensate medial plantar flap
Introduction. Reconstruction of heel soft tissue defects represents a true challenge for any surgeon due to the particularities of this anatomical region. The tissue used to reconstruct the heel area must be resistant, innervated, and adapted to take over the body weight. Innervated medial plantar fasciocutaneous flap is one of the best solutions to cover defects at the heel level.
Materials and Methods. We studied 5 patients, 4 males and one female, aged 42 to 67 years, who presented heel soft tissue defects of various etiologies. In all cases, the used reconstructive method was an insular innervated medial plantar fasciocutaneous flap.
Results. Immediate and late outcomes were good. No immediate complications of necrosis type were recorded in any of the cases, and 2 years postoperatively there was no evidence of ulceration or other type of flap injury. The socio-professional reintegration of the patients was relatively rapid and their satisfaction was high. Donor area morbidity was minimal.
Conclusions. Sensate medial plantar fasciocutaneous flap represents the first choice for the reconstruction of the heel soft tissue defects when patients’ local and general status allows it
Repeatability of facial soft tissue thickness measurements for forensic facial reconstruction using X-ray images
The repeatability of facial soft tissue thickness measurements at 10 standard
anatomical landmarks was evaluated using lateral X-ray images obtained from 50
adult subjects. The intra-and inter-observer error rates were calculated after four
practitioners took measurements using Denta Pacs 8.1 software. The results indicated
high inter- and intra-observer repeatability, suggesting X-ray images can be
used to measure facial soft tissue thicknesses for the purpose of craniofacial
reconstruction and superimposition
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