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Other Complications of Diabetes
Published in Jahangir Moini, Matthew Adams, Anthony LoGalbo, Complications of Diabetes Mellitus, 2022
Jahangir Moini, Matthew Adams, Anthony LoGalbo
Gangrene is a condition involving tissue death and decay (see Figure 13.3). It is caused by lost blood supplies or by bacterial infections. Removing dead tissue – often by amputation – as well as with antibiotics, usually treats it. There are three different types of gangrene: ∎ Dry gangrene – From lost blood supply to affected tissues∎ Wet gangrene – From bacterial infections, or in diabetics, a complication of foot ulcers∎ Gas gangrene – Usually caused by Clostridium perfringens, a bacterium that produces gas and toxins
Observing and Describing Disease
Published in Jeremy R. Jass, Understanding Pathology, 2020
Disease may be observed at the macroscopic level in the living patient, for example during clinical examination, surgery, endoscopy or through imaging modalities. More detailed inspection is possible in the case of dead tissue, whether this be at autopsy, in surgical cut-ups in the laboratory, museum specimens or static images. A complete and integrated perspective on the gross appearance of disease will be achieved in a sequence such as: magnetic resonance imaging → surgery → dissection of surgical specimen → correlation with imaging and histology.
Peripheral Vascular Disease
Published in Gozie Offiah, Arnold Hill, RCSI Handbook of Clinical Surgery for Finals, 2019
Management➢ Best done at a specialist multidisciplinary clinic.➢ Regularly inspect feet.➢ Appropriately fitted footwear & avoid walking barefoot.➢ Chiropodist for debriding calluses and for nail care.➢ If infected ulcer: Broad spectrum antibiotics.+/- Debridement of dead tissue.+/- Amputation of non-viable digits if adequate arterial supply for healing of amputationX-ray/MRI to rule out underlying osteomyelitis.➢ Consider revascularization if significant arterial disease.➢ Consider amputation if no response to medical or other surgical treatments.
Nano-hydroxyapatite as a delivery system: overview and advancements
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2021
Muhammad Usman Munir, Sajal Salman, Ibrahim Javed, Syed Nasir Abbas Bukhari, Naveed Ahmad, Naveed Akhter Shad, Farooq Aziz
Besides strengthening the bone skeleton, nHA based DDSs are being used as carriers for biopharmaceuticals such as vitamins, hormones, or anti-inflammatory substances. Several studies have investigated nHA for protein delivery and gene therapy applications [4–6] driven by their high loading capacity, biodegradability, and non-toxicity. nHA-based DDSs can be synthesised through chemical cross-linking and adsorption to attain various mechanical and physical aspects [7]. However, before clinical implementation, the pharmaceutical dosage form is required to achieve a desirable drug release and absorption profile to initiate the pharmacological effect [8]. Native nHA is not suitable for oral dosage formulation as nHA is rapidly deteriorated by acidic medium in gastric tract. This issue is resolved by forming an intestinal system of pH 8–9 with a targeted and controlled liberation [9,10]. In order to design bone targeting DDS, it is desirable to make a biocompatible and biodegradable drug carrier system that can improve the mechanical strength of bone tissue and deliver drug payload. Hence, calcium phosphates, mainly nHA, as carriers in bone disorders seem to be reasonable and apatite is considered as an osteoinductive as well as biocompatible carrier of pharmacological material. Moreover, apatite re-forms the dead tissue and enable remodelling. The morphology of nHA depends on the synthesis mechanism and impacts the physical properties. Controlling physical properties of HA plays a crucial role in elucidating the pathogenesis of diseases caused by exogenous and endogenous particles.
Comparison of different 4D CT-Perfusion algorithms to visualize lesions after microwave ablation in an in vivo porcine model
Published in International Journal of Hyperthermia, 2019
Keno K. Bressem, Janis L. Vahldiek, Christoph Erxleben, Beatrice Geyer, Franz Poch, Seyd Shnayien, Kai S. Lehmann, B. Hamm, Stefan M. Niehues
For comparison of the different algorithms, the lesion was first identified in the CTP source images showing the maximal arterial enhancement and then angulated orthogonal to the lesion’s longitudinal axis through multiplanar reconstruction. We placed circular ROIs with a diameter of 10 mm in the NLT and smaller ROIs with a diameter of 5 mm in the lesion. For each reconstruction, a slice thickness of 5 mm was used. To minimize the scattering of values, a total of two ROIs was drawn for each measurement, and the pooled values were used for later analysis. Since histological analyses showed a subdivision of the MWA lesions into a central white zone, which almost exclusively consisted of dead tissue, and a peripheral red zone, in which vital tissue can still be detected, we placed two ROIs in the central zone and two in the peripheral area to cover both zones. To ensure proper placement of the ROIs in the respective lesion zones, we used previously prepared histologic sections of the lesions for guidance. Therefore, the plane representing the histologic slice was chosen for the evaluation. For each region, we noted the mean and maximum values as well as the standard deviation. Upon evaluation of the different parameter maps, the exact same placement of the ROIs as in the CTP source images was ensured through automatic positioning by of the software, Thus, once defined, no manual adjustment of the ROIs had to be performed in the parameter maps, potentially reducing bias from different positioning between observers.
Effects of carbomer 940 hydrogel on burn wounds: an in vitro and in vivo study
Published in Journal of Dermatological Treatment, 2018
Farzad Hayati, Seyed Mehdi Ghamsari, Mohammad Mehdi Dehghan, Ahmad Oryan
In severe burns, the central zone ‘zone of necrosis’ is an expanded area in which the epidermis, dermis, and subcutaneous area are heavily affected and composed of dead tissue, inflammatory cell infiltration, edema, fibrin, and hemorrhages, due to the direct thermal injury. In the zone of stasis, ischemia plays a major role in tissue survival. This is the result of a combination of arteriole constriction, venule dilatation, platelet and red blood cell aggregation, and leukocyte adhesion (15). Salvaging the zone of stasis is the main focus of burn treatment, and various strategies, such as improving tissue perfusion, increasing the tolerance of the tissue to ischemia, and administration of antithrombotic and antioxidant agents have been suggested to prevent conversion of the ischemic zone to necrosis (2). We used laser Doppler flowmetry to evaluate alterations in the blood flow at different zones following skin-burn. Laser Doppler flowmetry is a noninvasive method in evaluating real-time skin perfusion and possible neovascularization during the process of cutaneous wound healing (23). Our results were in accordance with our previous study, in the first three days post-burning, and revealed that carbomer 940 can save the blood flow in the zone of stasis (17). There were significant differences on the following days of blood flow evaluations so that necrosis occurred in ischemic zones of the saline-treated rats whereas these zones remained viable in the rats treated by carbomer 940 (Figure 4).