Rat Thigh Research Articles

Novel fluorobenzothiazole as a dual inhibitor of gyrase B and topoisomerase IV against Gram-positive pathogens.

Aim: The development of a novel inhibitor targeting gyrase B and topoisomerase IV offers an opportunity to combat multidrug resistance. Methods: We investigated the activity of RBx 10080758 against Gram-positive bacteria in vitro and in vivo. Results: RBx 10080758 showed a potent 50% inhibitory concentration of 0.13μM and 0.25μM against gyrase B and topoisomerase IV, respectively, and exhibited strong whole-cell in vitro activity with MIC ranges of 0.015-0.06 and 0.015-0.03μg/ml against Staphylococcus aureus and Streptococcus pneumoniae, respectively. In a rat thigh infection model with methicillin-resistant S. aureus, RBx 10080758 at 45mg/kg exhibited a>3 log10 CFU reduction in thigh muscles. Conclusion: RBx 10080758 displayed potent activity against multiple multidrug-resistantGram-positive bacteria with a dual-targeting mechanism of action.

Neutropenic Rat Thigh Infection Model for Evaluation of the Pharmacokinetics/Pharmacodynamics of Anti-Infectives.

The neutropenic mouse infection model is extensively used to characterize the pharmacokinetics/pharmacodynamics (PK/PD) of anti-infective agents. However, it is difficult to evaluate agents following intravenous (i.v.) infusions using this model. Furthermore, in many drug discovery programs, lead identification and optimization is performed in rats, and pharmacology is performed in mice. Alternative models of infection are needed for robust predictions of PK/PD in humans. The rat is an alternative model of infection which can overcome the shortcomings of the mouse model. However, the rat neutropenic thigh infection (NTI) model has not been adequately characterized for evaluation of the PK/PD of anti-infectives. The aim of this study was to characterize the PK/PD of ciprofloxacin against bacterial pathogens in a rat NTI model. We studied the PK/PD relationships of ciprofloxacin against wild-type Escherichia coli, Acinetobacter baumannii, Pseudomonas aeruginosa, and Klebsiella pneumoniae in neutropenic Wistar rats following administration of 10, 30, and 100 mg/kg as single intravenous boluses and 30- and 60-min infusions. The PK/PD of ciprofloxacin against all four pathogens was AUC/MIC dependent and independent of the duration of administration at 10, 30, and 100 mg/kg. At human-equivalent rat doses, the PK/PD targets of ciprofloxacin achieved in rats for microbiological cure were similar to those reported in human patients. The neutropenic rat thigh infection model can be used to evaluate anti-infective agents intended to be administered as infusions in the clinic, and it complements the mouse model, increasing the robustness of PK/PD predictions in humans. IMPORTANCE Many antibiotics are administered as intravenous infusions in the clinic, especially in intensive care units. Anti-infective drug discovery companies develop clinical candidates that are intended to be administered as i.v. infusions in the clinic. However, there are no well-characterized models with which they can evaluate the PK/PD of the candidates following i.v. infusions. The neutropenic rat thigh infection model reported in this study helps in evaluating anti-infective agents that are intended to be administered as i.v. infusions in the clinic. The rat model is useful for simulating the clinical conditions for i.v. infusions for treatment of infections, such as acute bacterial skin and skin structure, lung, and urinary tract infections. This model is predictive of efficacy in humans and can serve as an additional confirmatory model, along with the mouse model, for determining the proof of concept and for making robust predictions of efficacy in humans.

Antitumor Activity of Luteolin Against Ehrlich Solid Carcinoma in Rats via Blocking Wnt/β-Catenin/SMAD4 Pathway.

Background Ehrlich solid carcinoma (ESC) is characterized by rapid proliferation and a short survival time. Because Ehrlich ascites carcinoma (EAC) resembles human cancer cells, Ehrlich solid and ascetic forms are commonly used to determine the anticancer effects of various compounds. Luteolin is a flavonoid compound found in many dietary sources, including carrots, peppers, celery, olive oil, peppermint, and oregano. Luteolin has potent anti-inflammatory, antidiabetic, antitumor, and antiapoptotic activities. Aims This study aims to investigate the antitumor activity of luteolin against ESC in rats by affecting the Wnt/β-catenin/SMAD4 pathway. Methods We introduced 0.15 ml of Ehrlich cells (2 × 106) ESC into the left hind thighs of rats. After eight days of inoculation, the rats orally received 25 mg/kg of luteolin daily. We stained sections of tumor tissues with Masson's trichrome. We used another part of the tumor tissue to assess gene and protein expression of Wnt, β-catenin, E-cadherin, and SMAD4. Results Treatment of carcinoma rats with luteolin increased the mean survival time and reduced tumor volume and weight. In addition, examination of tumor tissue stained with Masson's trichrome showed loosely to densely packed collagen fibers in between neoplastic cells and scattered papillary expansion of a loose blue band of collagen expression along the covering adipose connective tissue and extending in a fine strand in between muscle fibers, which was ameliorated by treating rats with luteolin. Finally, treating ESC in rats with luteolin overexpressed E-cadherin and downregulated Wnt, β-catenin, and SMAD4. Conclusions We found luteolin has antineoplastic activity against ESC by reducing tumor size and weight while improving the structure of muscle cells. It works by suppressing Wnt, β-catenin, and SMAD4, resulting in decreased tumor cell proliferation and differentiation. Additionally, luteolin overexpresses E-cadherin, leading to reduced tumor cell invasion and metastasis.

In vitro and in vivo anti-inflammatory, antibacterial and pharmacokinetic properties of baicalein

Baicalein is a bioactive flavone originally isolated from the roots of Scutellaria baicalensis, Scutellariala teriflora and Oroxylum indicum. The in vitro and in vivo anti-inflammatory and antibacterial properties of baicalein and pharmacokinetics after its single intramuscular administration were studied in Wistar rats. The in vitro anti-inflammatory activity of baicalein (10, 50 and 100 µM) was tested for its ability to inhibit the COX-2 enzyme by measuring PGE2 levels and determination of nitric oxide (NO) production in lipopolysaccharide (LPS) treated RAW 264.7 macrophage cells, in which baicalein was found to have significant inhibition of NO and PGE2 production in RAW 264.7 macrophage cells as compared with the LPS control group. The in vivo anti-inflammatory activity of baicalein (200 mg/kg) was assessed using the carrageenan-induced rat paw oedema model, following intramuscular injection. A significant percentage of inhibition of oedema volume was observed when compared with the carrageenan control group. In vitro and in vivo antibacterial activities of baicalein were determined by the micro broth dilution technique and neutropenic rat thigh infection model, wherein baicalein did not show any antibacterial property. Concentrations of baicalein were determined in rat plasma by high performance liquid chromatography (HPLC) after a single intramuscular administration at a dose of 200 mg/kg body weight, in which the mean peak plasma drug concentration (Cmax) of 0.77 ± 0.02 μg/mL was achieved at 0.08 h. The mean elimination half-life (t½β), the apparent volume of distribution (Vd(area)), total body clearance (Cl(B)) and mean residence time (MRT) were observed as 0.63 ± 0.06 h, 601.03 ± 28.18 L/kg, 677.39 ± 35.36 L/h/kg and 0.76 ± 0.06 h, respectively. Conclusively, in the present study, baicalein did not show in vitro or in vivo antibacterial property, but proved to have good anti-inflammatory activity. The available anti-inflammatory drugs have proved to have side effects in veterinary and human therapeutics. In this situation, baicalein may become an effective alternative to non-steroidal anti-inflammatory drugs and should also be studied in target animal species. Further research should be carried out to improve the solubility and bioavailability of baicalein through injectable routes.

Effectiveness of mixed tea plant extract gel with chitosan on fibroblast cells after tooth extraction of Wistar rats

ABSTRACTIntroduction: Tooth extraction can cause the damage of hard and soft tissue. When an injury occurs, fibroblast will respond in the wound healing process. Herbal medicines such as green tea and chitosan can be used in wound healing. The polyphenol content in green tea, namely EGCG, has an anti-inflammatory effect, increasing wound healing. In wound healing, chitosan promotes hemostasis and tissue recovery. Based on several previous studies, the use of 1.2% green tea extract was effective for improving wound healing in rat open wound models, chitosan 1% could trigger the proliferation of fibroblasts in the wound healing process after tooth extraction. The aim of this study is to analyze the effect of gel mixture of extract Camellia sinensis 1,2% with chitosan 1% on post-tooth extraction wound of Wistar rats. Methods: This was a randomized post-test only control group design using 40 Wistar rats which were randomly divided into 2 groups. Each group underwent intramuscular anesthesia on the rat's thigh and tooth extraction of mandibular left incisor. The treatment group was applied mixed gel of extract Camellia sinensis 1.2% and 1% chitosan as much as 0.01 ml and the control group was not given any treatment, after that decapitated on days 1, 3, 5, and 7. Result: The mean number of treated fibroblasts was higher than the control group on days 1, 3, 5, 7, respectively, 75.00; 176.00; 349.00 and 427.00 cells. The mean difference in the number of fibroblasts was significant with p-value 0.001 (p>0.05). Conclusions: Mixed extract gel of Camellia sinensis and chitosan increased fibroblasts in wound healing process after tooth extraction of Wistar rats with the highest mean of fibroblast on the 7th day.Keywords: mixed tea leaves,chitosan, fibroblast,wound healing

Osmotic Resistance of Rat’s Erythrocytes After Local Cold Injury

The effect of local cold injury in rats on the osmotic resistance of erythrocytes in the early and late reactive terms was investigated. Cryoinfluence was performed by pressing the applicator to the skin on the lateral surface of the rat thigh for 30, 60 and 120 s. Afterwards, the blood was collected from the aorta of animals after 1 and 4 hours and after 24 and 48 hours (early and late reactive periods, respectively). The effect of hypotonic solutions on cells was used as a test for osmotic resistance of erythrocytes. It is shown that the osmotic resistance of erythrocytes in the early reactive term increases (compared with control cells). In the late reactive term, the indices of osmotic resistance of erythrocytes after 24 hours approached the control values and after 48 hours they reached the norm. Osmotic resistance of erythrocytes in both reactive terms after local cold injury does not depend on the duration of cryoinfluence (30, 60, 120 s). The findings are considered from the standpoint of adaptive reactions that have an allostatic nature.

Mesenchymal stem cells moderate experimental autoimmune uveitis by dynamic regulating Th17 and Breg cells response.

Mesenchymal stem cells (MSCs) are adult stem cells from mesoderm with multi potential differentiation, and are being widely studied as a promising treatment for autoimmune diseases. The main inflammatory factors of experimental autoimmune uveitis (EAU) are T helper type 1 (Th1) and Th17. Regulatory B cells (Bregs) are a newly designated B cell subgroup, which has been proved to play a key role in regulating inflammation, autoimmunity and cancer. In this regard, we establish the EAU model by injecting interphotoreceptor retinoid-binding protein combined with complete Freund's adjuvant into the tail vein and bilateral thighs of rats, and inject MSCs or equal volume of phosphate buffer saline intraperitoneally on the day of immunization. Dynamic changes of cell subsets and cytokine expression are tested at different time periods to explore the relationship between MSCs treatment and disease prognosis during EAU course. Our results suggest that compared with the model control group, MSCs treatment can significantly reduce the production of Th1 and Th17 cytokines during EAU, while the production of regulatory B cells (Bregs) cytokines is significantly increased. At the same time, MSCs can reduce the proportion of Th17 in lymphocytes while the proportion of Bregs is elevated, thus inhibiting the differentiation and activity of interleukin in EAU rats. All this results provide more powerful evidence for cell therapy of autoimmune uveitis.

HDAC1 Expression, Histone Deacetylation, and Protective Role of Sodium Valproate in the Rat Dorsal Root Ganglia After Sciatic Nerve Transection.

Nerve injury is an important reason of human disability and death. We studied the role of histone deacetylation in the response of the dorsal root ganglion (DRG) cells to sciatic nerve transection. Sciatic nerve transection in the rat thigh induced overexpression of histone deacetylase 1 (HDAC1) in the ipsilateral DRG at 1-4h after axotomy. In the DRG neurons, HDAC1 initially upregulated at 1h but then redistributed from the nuclei to the cytoplasm at 4h after axotomy. Histone H3 was deacetylated at 24h after axotomy. Deacetylation of histone H4, accumulation of amyloid precursor protein, a nerve injury marker, and GAP-43, an axon regeneration marker, were observed in the axotomized DRG on day 7. Neuronal injury occurred on day 7 after axotomy along with apoptosis of DRG cells, which were mostly the satellite glial cells remote from the site of sciatic nerve transection. Administration of sodium valproate significantly reduced apoptosis not only in the injured ipsilateral DRG but also in the contralateral ganglion. It also reduced the deacetylation of histones H3 and H4, prevented axotomy-induced accumulation of amyloid precursor protein, which indicated nerve injury, and overexpressed GAP-43, a nerve regeneration marker, in the axotomized DRG. Therefore, HDAC1 was involved in the axotomy-induced injury of DRG neurons and glial cells. HDAC inhibitor sodium valproate demonstrated the neuroprotective activity in the axotomized DRG.

Дія цитрату ванадію на активність ензимів вуглеводного обміну в підшлунковій залозі та скелетному м’язі стегна вагітних самок щурів

During pregnancy, the body undergoes physiological, endocrine and metabolic changes. There is an imbalance of trace elements, including vanadium. To compensate for the loss of this trace element and to improve metabolic processes in pregnant women an organic compound - vanadium citrate was used. The aim of our research was to investigate the effect of vanadium citrate on glucose-6-phosphate dehydrogenase and lactate dehydrogenase activity in pancreas and the skeletal muscle in pregnant female rats. The research was conducted on female white laboratory rats weighing 140-160 g, which were divided into five groups: group I - non-pregnant animals, group II - pregnant females consuming pure water without additives, rats of groups III, IV, V in the period of mating and pregnancy received the solution of vanadium citrate in concentrations of 3,75, 15,625 та 62,5 mkg V/ kg body weight, respectively. The material for the study included homogenates of pancreas and the skeletal muscle of the thigh of pregnant female rats, in which glucose-6-phosphate dehydrogenase and lactate dehydrogenase activity was determined. Glucose-6-phosphate dehydrogenase activity in pancreas and skeletal muscle of pregnant female rats reduced as compared to non-pregnant rats. This is due to the inhibition of glucose oxidation in the pentose phosphate pathway. Lactate dehydrogenase activity in these tissues in pregnant animals increased as compared to group I. The increase in the activity of lactate dehydrogenase in pregnant females indicates the activation of glycolysis and the intensive use of glucose in the energy metabolism. Under the conditions of exposure of rats to vanadium citrate, glucose-6-phosphate dehydrogenase activity in pancreas increased significantly in group IV, while lactate dehydrogenase activity decreased in group V as compared to pregnant animals of group ІІ which did not consume vanadium. In the muscles of pregnant animals exposed to vanadium, glucose-6-phosphate dehydrogenase activity significantly reduced in groups III and IV, but increased in group V, whereas lactate dehydrogenase activity decreased in group III and increased in group V as compared to pregnant animals in group II. Vanadium contributes dose-dependently to the approximation of glucose-6-phosphate dehydrogenase and lactate dehydrogenase activity in pancreas and skeletal muscle of pregnant animals to the values of their activity in non-pregnant animals. It causes a normalizing effect on lactate dehydrogenase activity and promotes oxidation of glucose in the pentose phosphate pathway. This allows us to consider this trace element as a potential dietary supplement for pregnant women. Prospects for further studies include the study of hematological and biochemical parameters, protein metabolism in rats in different physiological and pathological conditions under the action of vanadium citrate at different concentrations.

XDR-Klebsiella pneumoniae isolates harboring blaOXA-48: In vitro and in vivo evaluation using a murine thigh-infection model.

Blood stream infection with extensively drug-resistant-carbapenamase producing Klebsiella (K.) pneumoniae usually represents a major threat with medical challenges among hospitalized cancer patients with poor functional status and underlying diseases. Accordingly, the aim of the study was to evaluate the efficacy of different antibiotics either alone or in combinations against extensively drug-resistant-OXA-48 producing K. pneumoniae clinical isolates that were previously recovered from febrile neutropenic pediatric cancer patients. The antimicrobial activity of amikacin, gentamicin, colistin, ertapenem, imipenem, meropenem and tigecycline was assessed by broth microdilution method. The results revealed that all the tested OXA-48 producing K. pneumoniae isolates exhibited extensively drug-resistant phenotype and all of them were susceptible to tigecycline. Checkerboard method was used to determine the fraction inhibitory concentration index, to further classify the effect of antibiotic combination as synergistic, additive, indifferent, or antagonistic effect. The results revealed that in vitro dual carbapenem combination of ertapenem with meropenem had shown synergistic effect against all of the tested isolates. Additionally, synergistic effect of meropenem with colistin was detected among three of four isolates tested. Herein we investigated the in vivo activity of colistin, meropenem alone and in combination in a rat thigh infection model. The results showed that addition of meropenem to colistin was not effective at reduction of bacterial count as compared to colistin alone at 24 h post treatment. Accordingly, we can conclude that in vitro antibiotic combinations of dual carbapenems (ertapenem plus meropenem) and meropenem plus colistin showed synergism in 100% and 75% of the tested isolates, respectively. Colistin alone had significantly reduced bacterial count while its combination with meropenem was not superior to monotherapy in murine thigh infection model. Impact statement The present study aimed to evaluate the effectiveness of various antibiotics both in vitro and in vivo using murine animal model either alone or in combination against various strains of extensively drug-resistant (XDR) Klebsiella pneumoniae, life-threatening pathogens of relevant medical importance isolated from febrile neutropenic pediatric cancer patients. This work also emphasizes how to select the appropriate antibiotics options and help the physicians to choice the appropriate antibiotic for the treatment of such superbugs (extensively drug-resistant (XDR) Klebsiella pneumoniae). The results showed that in vitro dual carbapenem combination of ertapenem with meropenem had shown synergistic effect against all of the tested XDR isolates. Antibiotic combinations of dual carbapenems and meropenem plus colistin showed synergism in 100% and 75% of the testes isolates, respectively. Results of the in vivo evaluation, colistin alone had significantly reduced bacterial count while its combination with meropenem was not superior to monotherapy.

Sinensetin regulates age-related sarcopenia in cultured primary thigh and calf muscle cells

BackgroundSarcopenia, the decline of skeletal muscle tissue attributed to primary aging is a major concern in older adults. Flavonoids might have potential benefits by modulating the regulation of satellite cells, thus preventing muscle loss. Sinensetin (SIN), a citrus methylated flavone with anti-inflammatory and anti-proliferative activity, can enhance lipolysis. The objective of the present study was to investigate whether SIN might have sarcopenia-suppressing effect on satellite cells from thigh and calf muscle tissues of young and old rats.MethodsPrimary muscle cells were obtained from thigh and calf tissues of young and old group rats by dissection. Obtained satellite cells were incubated with indicated concentrations of SIN (50 and 100 μM) treated and untreated condition in differentiation medium. Morphological changes of cells were examined using a phase-contrast microscope. Protein expression levels of myoD and myogenin were analyzed by Western blot. Cells treated with or without SIN under differentiation condition were also immunocytochemically stained for myogenin and 4′,6-diamidino-2-phenylindole (DAPI).ResultsMorphologically, the differentiation extracted satellite cells was found to be more evident in SIN treated group of aged rat′s cells than that in SIN untreated group. Expression levels of myoD and myogenin proteins involved in myogenesis were increased upon treatment with SIN.ConclusionsCollectively, our results indicate that SIN can alleviate age-related sarcopenia by increasing differentiation rate and protein levels of myoD and myogenin.

A faster PISTOL for 1 H MR-based quantitative tissue oximetry.

Quantitative mapping of oxygen tension (pO2 ), noninvasively, could potentially be beneficial in cancer and stroke therapy for monitoring therapy and predicting response to certain therapies. Intracellular pO2 measurements may also prove useful in tracking the health of labeled cells and understanding the dynamics of cell therapy in vivo. Proton Imaging of Siloxanes to map Tissue Oxygenation Levels (PISTOL) is a relatively new oximetry technique that measures the T1 of administered siloxanes such as hexamethyldisiloxane (HMDSO), to map the tissue pO2 at various locations with a temporal resolution of 3.5minutes. We have now developed a siloxane-selective Look-Locker imaging sequence equipped with an echo planar imaging (EPI) readout to accelerate PISTOL acquisitions. The new tissue oximetry sequence, referred to as PISTOL-LL, enables the mapping of HMDSO T1 , and hence tissue pO2 in under one minute. PISTOL-LL was tested and compared with PISTOL in vitro and in vivo. Both sequences were used to record dynamic changes in pO2 of the rat thigh muscle (healthy Fischer rats, n=6), and showed similar results (P>0.05) as the other, with each sequence reporting a significant increase in pO2 (P<0.05) under hyperoxia compared with steady state normoxia. This study demonstrates the ability of the new sequence in rapidly and accurately mapping the pO2 changes and accelerating quantitative 1 H MR tissue oximetry by approximately 4-fold. The faster PISTOL-LL technique could enable dynamic 1 H oximetry with higher temporal resolution for assesing tissue oxygentation and tracking the health of transplanted cells labeled with siloxane-based probes. With minor modifications, this sequence can be useful for 19 F applications as well.

TISSUE IMMUNE CELLS AND THEIR ROLE IN THE HEALING PROCESS OF INFECTED RADIATION ULCERS UNDER THE IMPACT OF PHOTODYNAMIC THERAPY (EXPERIMENTAL STUDY).

to study the effect of antibacterial photodynamic therapy (PDT) on the dynamics of tissue neutrophilic leukocytes CD18 and tissue macrophages ED1 in the tissues of infected radiation ulcer during the stages of sponta- neous healing and in the treatment of PDTMaterials and methods. Infected radiation ulcer was modeled by local X-ray irradiation of the rat thigh skin at a dose of 85.0 Gy, followed by applying to the surface of the ulcer bacterial suspension of S. аureus. PDT was performed using a «Barva-LED/630» photonic apparatus and a methylene blue photosensitizer. The effect of PDT on the state of cellular immunity was determined using an immunohistochemical method based on the quantitative indices of neutrophilic leukocytes CD18 and ED1 macrophages during the stages of healing of an infected radiation ulcer. In the course of spontaneous healing of the ulcer (control I), the dynamics of changes in the relative vo- lume of tissue neutrophil leukocytes CD18 and ED1 macrophages in the lesion zone, a decrease in the CD18 / ED1 index more than 2 times indicated that switching of the neutrophil response to macrophage occurred before 52nd days of observations. When infected with S. аureus X-ray (control II), the switching of the neutrophil response to the macrophage did not occur during the entire observation period. When using PDT in the case of S. аureus infected ulcer (experimental group), the decrease in the CD18 / ED1 index was determined from the 21st day of observation. The positive effect of the antibacterial PDT method of infected S. аureus radiation ulcers was manifes- ted by complete microbial decontamination of the wound, reduction of phases of the wound process, complete hea- ling of radiation ulcers.The use of PDT has led to the death of bacteria, a decrease in the number of neutrophilic leukocytes and an increase in macrophages in the lesion area, the switching of the neutrophilic response to the reaction of monocyte-macrophage cells in the early stages of healing.

Early morphological changes in the knee joint of rats after opioid exposure

The objective is to study early morphological changes of rats’ knee joint after experimental opioid exposure. Materials and methods. Research material is mature, non-breeding male rats 4.5 months old (n = 16) with body weight 80 g. Animals were divided into 2 groups: experimental and control. The experimental group of rats (n = 10) got the injection of nalbuphine hydrochloride intramuscularly, one time per day during 7 days; initial dose – 8 mg/kg. The condition of chronic opioid exposure has been modeled. The rats of control group (n = 6) got the injection of physiological solution intramuscularly during 7 days. The distal epiphysis of rat thigh and proximal epiphysis of rat tibia taking into account the preservation of topographical correlation of the knee joint structural components have been used for histological analysis. Following decalcination, the histologic specimens have been stained with hematoxylin, eosin, azure and azan by Heidenhain. The thickness of the cover synovial layer of articular cartilage has been measured. Results. The architectonics of articular cartilage distorts, the cover synovial layer of articular cartilage gets thinner due to experimental action of opiates. There is also tendency towards volume decrease of chondrocytes in proliferation zone and thickness loss of the cartilage. Conclusions. At the early stage of opioid exposure the structure abnormality of laboratory rats’ knee joint can be seen in the synovial layer and in the zone of chondrocytes proliferation. These research data can be a prerequisite for opioid chondropathy.

Allocation of rhodamine-loaded nanocapsules from blood circulatory system to adjacent tissues assessed in vivo by fluorescence spectroscopy

Modern fluorescent modalities play an important role in the functional diagnostic of various physiological processes in living tissues. Utilizing the fluorescence spectroscopy approach we observe the circulation of fluorescent-labelled nanocapsules with rhodamine tetramethylrhodamine in a microcirculatory blood system. The measurements were conducted transcutaneously on the surface of healthy Wistar rat thighs in vivo. The administration of the preparation capsule suspension with a rhodamine concentration of 5 mg kg−1 of the animal weight resulted in a two-fold increase of fluorescence intensity relative to the baseline level. The dissemination of nanocapsules in the adjacent tissues via the circulatory system was observed and assessed quantitatively. The approach can be used for the transdermal assessment of rhodamine-loaded capsules in vivo.

Diffuse Speckle Contrast Analysis Assisted Intraoperative Blood Flow Monitoring in the Rat Model of Femoral Arterial Occlusion.

The rodent model has been largely used for understanding specific disease pathophysiology, with low cost and the large spectrum from genetic strains. Here, we present a diffuse speckle contrast analysis (DSCA) system to measure blood flow changes non-invasively in rat's thigh and paw during femoral arterial occlusion (FAO) surgery which is the procedure for inducing peripheral arterial disease. The blood flow index in rat's paw showed significant decrease according to arterial occlusion. Moreover, we analyzed cross-correlation between two measurement positions. The results showed the affinity with hemodynamic response. In conclusion, the DSCA system secured the intraoperative blood flow monitoring during FAO surgery in a rat model.

Amelioration of Endotoxin-Induced Inflammatory Toxic Response by a Metal Chelator in Rat Eyes.

PurposeMetal ions play a key role in exacerbating toxicity associated with oxidative stress and inflammation. This study examines the effects of a formulation containing the metal chelator ethylenediaminetetraacetic acid (EDTA) and permeability enhancer methyl sulfonyl methane (MSM) on the early course of inflammation in endotoxin-induced uveitis (EIU). The proprietary MSM/EDTA formulation of Livionex, Inc., which was used for this study, is covered by several patents and pending patent applications.MethodsEIU was induced by using subcutaneous injection of lipopolysaccharide (LPS) into the thighs of Lewis rats. Treatment consisted of topical application to the eyes of either PBS or eye drops designated as ME that contain EDTA and MSM. Clinical signs of uveitis were monitored at 6 and 24 hours postinjection. Oxidative and inflammatory markers were evaluated by ELISA or immunohistochemistry.ResultsRats treated with ME showed fewer clinical signs of uveitis including reduced miosis, fibrinous exudates, and dilated blood vessels. The aqueous humor of treated rats contained fewer leukocytes, lower protein levels, and less PGE2. Formation of protein adducts with the lipid peroxidation end-product, 4-hydroxynonenal, expression of NF-κB, TNF-α, and MMP-9 were all reduced in rats treated with ME.ConclusionsOur results indicate that ME eye drops downregulate the ocular inflammatory response in LPS treated rats, suggesting that induction of EIU involves metal ions and chelation therapy with ME is a potential treatment for uveitis.

Consumer awareness, proximate composition, and sensory properties of processed African giant rat (Cricetomys gambianus) thigh meat

Abstract This study investigated the knowledge of consumption of giant rat meat within the University of Ilorin, Kwara State Nigeria and further determined the effect of processing methods on the most preferred meat part (thigh meat). After the survey, two male and female giant rats each were obtained from a farm and slaughtered according to standard method. A 2 × 2 design was used to obtain four samples. The male rats were boiled and then divided into two portions. One portion was deep-fat fried and the other grilled to produce. The same process was employed for the female samples. Proximate composition and sensory properties of the processed thigh meat was also assessed. Majority of the respondents (27) prefer the hind limb (thigh) of the giant rat compared to the head (3), ribs and stomach area (5) and the fore limbs (8). The proximate composition of the raw giant rat meat were not affected by the sex, since the values were very similar. Protein is the major nutrients in the meat (approx. 24%), while fats, ash, fibre and carbohydrate were very low. Frying and grilling resulted in significant reduction in the proximate composition of the meat. Grilling showed slightly higher protein contents (approx. 22%) than the fried samples (approx. 18%). In general, there was no significant (p ≤ .05) difference in the sensory properties of the processed meat. The low fat content of the giant rat meat is advantageous for adults and people suffering from fat related diseases. In conclusion, giant rat meat is popular among students and staff of the University of Ilorin, but its low consumption pattern is due to the limited amount raised or within the University environs.

Pedicled Transplantation of Axially Vascularized Bone Constructs in a Critical Size Femoral Defect.

Axial vascularization represents a mandatory requirement for clinically applied larger scale vascularized bone grafts. The aim of this study was to combine the arteriovenous (AV) loop model in the rat with a critically sized femoral bone defect and to successfully transplant axially vascularized bone constructs into the defect. In Groups A and C, an AV loop together with a clinically approved hydroxyapatite and beta-tricalcium phosphate (HA/β-TCP) matrix, mesenchymal stem cells, and recombinant human bone morphogenetic protein 2 were implanted into a newly designed porous titanium chamber with an integrated osteosynthesis plate in the thighs of rats, whereas in Groups B and D, the same matrix composition without AV loop and, in Group E, only the HA/β-TCP matrix were implanted. After 6 weeks, the constructs were transplanted into a 10 mm femoral defect created in the same leg, in Groups A and C, under preservation of the AV loop pedicle. Group F served as a control group with an empty chamber. Ten days (Groups A and B) and 12 weeks (Groups C-F) after transplantation, the femora together with the constructs were explanted and investigated using computed tomography (CT), micro-CT, X-ray, histology, and real-time polymerase chain reaction (RT-PCR). Ten days after transplantation, Group A showed a maintained vascular supply leading to increased vascularization, cell survival in the scaffold center, and bone generation compared to Group B. After 12 weeks, there was no difference detectable among all groups regarding total vessel number, although Group C, using the AV loop, still showed increased vascularization of the construct center compared to Groups D and E. In Group C, there was still enhanced bone generation detectable compared to the other groups and increased bony fusion rate at the proximal femoral stump. This study shows the combination of the AV loop model in the rat with a critically sized femoral defect. By maintenance of the vascular supply, the constructs initially showed increased vascularization, leading to increased bone formation and bony fusion in the long term.

Collagen-Elastin and Collagen-Glycosaminoglycan Scaffolds Promote Distinct Patterns of Matrix Maturation and Axial Vascularization in Arteriovenous Loop-Based Soft Tissue Flaps.

Autologous free flaps are the criterion standard for reconstructions of complex soft tissue defects; however, they are limited by donor-site morbidities. The arteriovenous (AV) loop model enables the generation of soft tissue constructs based on acellular dermal matrices with a functional microvasculature and minimal donor site morbidity. The ideal scaffold for AV loop-based tissue engineering has not been determined. AV loops were placed into subcutaneous isolation chambers filled with either a collagen-elastin scaffold or a collagen-glycosaminoglycan scaffold in the thighs of rats. Matrix elasticity, neoangiogenesis, cell migration, and proliferation were compared after 14 and 28 days. Mean vessel count and area had increased in both matrices at 28 compared with 14 days. Collagen-elastin matrices showed a higher mean vessel count and area compared with collagen-glycosaminoglycan matrices at 14 days. At 28 days, a more homogeneous vascular network and higher cell counts were observed in collagen-elastin matrices. Collagen-glycosaminoglycan matrices, however, exhibited less volume loss at day 28. Collagen-based scaffolds are suitable for soft tissue engineering in conjunction with the AV loop technique. These scaffolds exhibit distinct patterns of angiogenesis, cell migration, and proliferation and may in the future serve as the basis of tissue-engineered free flaps as an individualized treatment concept for critical wounds.