Percentage Of Necrotic Area Research Articles

Tumor-Infiltrating Lymphocytes in Necrotic Tumors after Melanoma Neoadjuvant Anti-PD-1 Therapy Correlate with Pathologic Response and Recurrence-Free Survival.

Neoadjuvant anti-PD-1 therapy in melanoma may increase tumor-infiltrating lymphocytes (TIL), and more TIL are associated with better treatment response. A major pathologic response (MPR) in melanoma after neoadjuvant anti-PD-1 therapy usually comprises tumor necrosis and fibrosis. The role of TIL in necrotic tumor necrosis (nTIL) has not been explored. We performed CD3 and CD8 IHC stains on 41 melanomas with geographic necrosis. Of the 41, 14 were immunotherapy-naïve, and 27 had been treated with one dose of neoadjuvant anti-PD-1 in two clinical trials. CD3+ and CD8+ nTIL were graded as absent/minimal or moderate/brisk. The percentage of necrotic areas in the tumor bed before and after treatment was quantified. The endpoints were MPR and 5-year recurrence-free survival (RFS). In the immunotherapy-naïve cohort, 3/14 (21%) specimens had moderate/brisk CD3+, and 2/14 (14%) had moderate/brisk CD8+ nTIL. In the treated cohort, 16/27 (59%) specimens had moderate/brisk CD3+, and 15/27 (56%) had moderate/brisk CD8+ nTIL, higher than those of the naïve cohort (CD3, P = 0.046; CD8, P = 0.018). Tumor necrosis was significantly increased after anti-PD-1 therapy (P = 0.007). In the treated cohort, moderate/brisk CD3+ and CD8+ nTIL correlated with MPR (P = 0.042; P = 0.019, respectively). Treated patients with moderate/brisk CD3+ nTIL had higher 5-year RFS than those with absent/minimal nTIL (69% vs. 0%; P = 0.006). This persisted on multivariate analysis (HR, 0.16; 95% confidence interval, 0.03-0.84; P = 0.03), adjusted for pathologic response, which was borderline significant (HR, 0.26; 95% confidence interval, 0.07-1.01; P = 0.051). CD3+ and CD8+ nTIL are associated with pathologic response and 5-year RFS in patients with melanoma after neoadjuvant anti-PD-1 therapy.

Spermidine Exerts Protective Effects in Random-Pattern Skin Flap Survival in Rats: Possible Involvement of Inflammatory Cytokines, Nitric Oxide, and VEGF.

Distal necrosis and inflammation are two of the most common health consequences of random-pattern skin flaps survival (SFS). Anti-inflammatory effects of spermidine have been identified in various studies. On the other hand, considering the involvement of the nitric oxide molecule in the spermidine mode of action and also its role in skin tissue function, we analyzed the possible effects of spermidine on the SFS and also, potential involvement of nitrergic pathway and inflammatory cytokine in these phenomena. Each rat was pretreated with either a vehicle (control) or various doses of spermidine (0.5, 1, 3, 5, 10 and 30 mg/kg) and then was executed a random-pattern skin flap paradigm. Also, spermidine at the dose of 5 mg/kg was selected and one group rats received spermidine 20 min prior to surgery and one additional dose 1 day after operation. Then, 7 days after operations, interleukin (IL)-6, tumor necrosis factor (TNF)-α, interferon-gamma (IFN-γ), and nitrite levels were inquired in the tissue samples by ELIZA kit. Vascular endothelial growth factor expression was assessed by DAPI staining and fluorescent microscopes. The concentrations of three polyamines, including spermidine, spermine, and cadaverine, were analyzed using HPLC. Pretreatment with spermidine 5 mg/kg improved SFS considerably in microscopic skin H&E staining analysis and decreased the percentage of necrotic area. Moreover, spermidine exerted promising anti-inflammatory effects via the modulation of nitric oxide and reducing inflammatory cytokines. Spermidine could improve skin flaps survival, probably through the nitrergic system and inflammation pathways. This preclinical study provides level III evidence for the potential therapeutic effects of spermidine on SFS in rats, based on the analysis of animal models. Further studies are needed to confirm these findings in clinical settings. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Photodynamic therapy with paclitaxel-encapsulated indocyanine green-modified liposomes for breast cancer.

Photodynamic therapy (PDT) involves the administration of a photosensitizing agent and irradiation of light at an excitation wavelength that damages tumor cells without causing significant damage to normal tissue. We developed indocyanine green (ICG)-modified liposomes in which paclitaxel (PTX) was encapsulated (ICG-Lipo-PTX). ICG-Lipo-PTX accumulates specifically in tumors due to the characteristics of the liposomes. The thermal and photodynamic effects of ICG and the local release of PTX by irradiation are expected to induce not only antitumor effects but also cancer immunity. In this study, we investigated the antitumor effects of ICG-Lipo-PTX in breast cancer. The antitumor effects of ICG-Lipo-PTX were examined in xenograft model mice subcutaneously implanted with KPL-1 human breast cancer cells. ICG-Lipo-PTX, ICG-Lipo, or saline was administered intraperitoneally, and the fluorescence intensity was measured with a fluorescence imaging system (IVIS). Intratumor temperature, tumor volume, and necrotic area of tumor tissue were also compared. Next, we investigated the induction of cancer immunity in an allogeneic transplantation model in which BALB-MC mouse breast cancer cells were transplanted subcutaneously in the bilateral inguinal region. ICG-Lipo-PTX was administered intraperitoneally, and PDT was performed on only one side. The fluorescence intensity measured by IVIS and the bilateral tumor volumes were compared. Cytokine secretory capacity was also evaluated by ELISPOT assay using splenocytes. In the xenograft model, the fluorescence intensity and temperature during PDT were significantly higher with ICG-Lipo-PTX and ICG-Lipo in tumor areas than in nontumor areas. The fluorescence intensity in the tumor area was reduced to the same level as that in the nonirradiated area after two times of irradiation. Tumor growth was significantly reduced and the percentage of necrotic area in the tumor was higher after PDT in the ICG-Lipo-PTX group than in the other groups. In the allograft model, tumor growth on day 14 in the ICG-Lipo-PTX group was significantly suppressed not only on the PDT side but also on the non-PDT side. In addition, the secretion of interferon-γ and interleukin-2 was enhanced, whereas that of interleukin-10 was suppressed, in the ICG-Lipo-PTX group. The PDT therapy with ICG-Lipo-PTX may be an effective treatment for breast cancer.

Desmopressin enhances random-pattern skin flap survival in rats: Possible role of vasopressin Type-1a and 2 receptors

BackgroundMany drugs have been explored for their role in improving skin flap survival. 1-deamino-8-D-arginine vasopressin (DDAVP or desmopressin) is a synthesized form of anti-diuretic hormone (ADH) and a selective agonist for vasopressin type-2 receptors (V2 receptors). Desmopressin has been shown to improve endothelial function, induce vasodilation, and reduce inflammation. We aimed to evaluate its efficacy in enhancing flap survival and assess the role of vasopressin receptors in this process. Materials and methodsWe randomly assigned six male Wistar rats to each study group. Different doses of desmopressin were injected intraperitoneally to find the most effective amount (8 μg/rat). SR-49059, a selective V1a receptor antagonist, was given at 2μg/rat before providing the most effective dose of desmopressin (8μg/rat). Histopathological assessments, quantitative measurements of interleukin-1β (IL-1β), Tumor necrosis factor-alpha (TNF-α), and Nuclear Factor-κB (NF-κB), optical imaging, and measurement of the expression levels of V2 receptor in the rat skin tissue were performed. ResultsDesmopressin (8μg/rat) significantly reduced the mean percentage of necrotic area compared to the control group (19.35% vs 73.57%). Histopathological evaluations revealed a notable reduction in tissue inflammation, edema, and degeneration following administration of desmopressin (8). The expression of the V2 receptor was increased following desmopressin administration. It also led to a reduction in IL-1β, TNF-α, and NF-κB levels. The protective effect of desmopressin on flap survival was reversed upon giving SR-49059. The optical imaging revealed enhanced blood flow in the desmopressin group compared to the control group. ConclusionsDesmopressin could be repurposed to improve flap survival. V1a and V2 receptors probably mediate this effect.

Liver regeneration after portal vein embolization: comparison between absolute ethanol and N-butyl-cyanoacrylate in an in vivo rat model.

To compare the effects of absolute ethanol (ethanol) and N-butyl-cyanoacrylate (NBCA) on non-embolized liver lobe regeneration in a rat model. Twenty-seven Sprague-Dawley rats underwent portal vein embolization (PVE) using ethanol:lipiodol, 1:1 (ethanol group, n = 11, 40.74%), NBCA:lipiodol, 1:1 (NBCA group, n = 11, 40.74%), or sham treatment (sham group, n = 5, 18.52%). The non-embolized and embolized lobe-to-whole liver weight ratios 14 days after PVE were compared among the groups (n = 5, 18.52%). The expressions of CD68 and Ki-67 and embolized-lobe necrotic area percentages one day after PVE were compared between the ethanol (n = 3, 11.11%) and NBCA (n = 3, 11.11%) groups. The non-embolized lobe-to-whole liver weight ratio after PVE was significantly higher in the NBCA group (n = 5, 33.33%) than in the ethanol group (n = 5, 33.33%) (84.28% ± 1.53% vs. 76.88% ± 4.12%, P = 0.029). The embolized lobe-to-whole liver weight ratio after PVE was significantly lower in the NBCA group than in the ethanol group (15.72% ± 1.53% vs. 23.12% ± 4.12%, P = 0.029). The proportions of CD68- and Ki-67-positive cells in the non-embolized lobe after PVE were significantly higher in the NBCA group (n = 30, 50%) than in the ethanol group (n = 30, 50%) [60 (48-79) vs. 55 (37-70), P = 0.003; 1 (0-2) vs. 1 (0-2), P = 0.004]. The embolized-lobe necrotic area percentage after PVE was significantly larger in the NBCA group (n = 30, 50%) than in the ethanol group (n = 30, 50%) [29.46 (12.56-83.90%) vs. 16.34 (3.22-32.0%), P < 0.001]. PVE with NBCA induced a larger necrotic area in the embolized lobe and promoted greater non-embolized liver lobe regeneration compared with PVE with ethanol.

Is aryl hydrocarbon receptor antagonism after ischemia effective in alleviating acute hepatic ischemia-reperfusion injury in rats?

Aryl hydrocarbon receptors (AhRs) have been reported to be important mediators of ischemic injury in the brain. Furthermore, the pharmacological inhibition of AhR activation after ischemia has been shown to attenuate cerebral ischemia-reperfusion (IR) injury. Here, we investigated whether AhR antagonist administration after ischemia was also effective in ameliorating hepatic IR injury. A 70% partial hepatic IR (45-min ischemia and 24-h reperfusion) injury was induced in rats. We administered 6,2′,4′-trimethoxyflavone (TMF, 5 mg/kg) intraperitoneally 10 min after ischemia. Hepatic IR injury was observed using serum, magnetic resonance imaging-based liver function indices, and liver samples. TMF-treated rats showed significantly lower relative enhancement (RE) values and serum alanine aminotransferase (ALT) and aspartate aminotransferase levels than did untreated rats at 3 h after reperfusion. After 24 h of reperfusion, TMF-treated rats had significantly lower RE values, ΔT1 values, serum ALT levels, and necrotic area percentage than did untreated rats. The expression of the apoptosis-related proteins, Bax and cleaved caspase-3, was significantly lower in TMF-treated rats than in untreated rats. This study demonstrated that inhibition of AhR activation after ischemia was effective in ameliorating IR-induced liver injury in rats.

Experimental study of the effects of nitroglycerin, botulinum toxin A, and clopidogrel on bipedicled superficial inferior epigastric artery flap survival

Beneficial effects could be achieved by various agents such as nitroglycerin, botulinum toxin A (BoTA), and clopidogrel to improve skin flap ischaemia and venous congestion injuries. Eighty rats were subjected to either arterial ischaemia or venous congestion and applied to a bipedicled U-shaped superficial inferior epigastric artery (SIEA) flap with the administration of nitroglycerin, BoTA, or clopidogrel treatments. After 7 days, all rats were sacrificed for flap evaluation. Necrotic area percentage was significantly minimized in flaps treated with clopidogrel (24.49%) versus the ischemic flaps (34.78%); while nitroglycerin (19.22%) versus flaps with venous congestion (43.26%). With ischemia, light and electron microscopic assessments revealed that nitroglycerin produced degeneration of keratinocytes and disorganization of collagen fibers. At the same time, with clopidogrel administration, there was an improvement in the integrity of these structures. With venous congestion, nitroglycerin and BoTA treatments mitigated the epidermal and dermal injury; and clopidogrel caused coagulative necrosis. There was a significant increase in tissue gene expression and serum levels of vascular endothelial growth factor (VEGF) in ischemic flaps with BoTA and clopidogrel, nitroglycerin, and BoTA clopidogrel in flaps with venous congestion. With the 3 treatment agents, gene expression levels of tumor necrosis factor-α (TNF-α) were up-regulated in the flaps with ischemia and venous congestion. With all treatment modalities, its serum levels were significantly increased in flaps with venous congestion and significantly decreased in ischemic flaps. Our analyses suggest that the best treatment option for ischemic flaps is clopidogrel, while for flaps with venous congestion are nitroglycerin and BoTA.

Cannabidiol Improves Random-Pattern Skin Flap Survival in Rats: Involvement of Cannabinoid Type-2 Receptors.

One of the major complications associated with random-pattern skin flaps is distal necrosis. Cannabidiol (CBD) has recently gained much attention as a therapeutic anti-inflammatory agent. We aimed to evaluate the efficacy of CBD on the random-pattern skin flap survival (SFS) in rats and to explore the possible involvement of cannabinoid type-2 (CB2) receptors. In this controlled experimental study, we randomly divided male Wistar rats into seven study groups (six rats each). We performed a random-pattern skin flap model in each rat following pretreatment with vehicle (control) or multiple doses of CBD (0.3, 1, 5, or 10 mg/kg). In a separate group, we injected SR144528 (2 mg/kg), a high affinity and selective CB2 inverse agonist, before the most effective dose of CBD (1 mg/kg). A sham nontreated and nonoperated group was also included. Seven days after surgeries, the percentage of necrotic area (PNA) was calculated. Histopathological microscopy, CB2 expression level, and interleukin (IL)-1β and tumor necrosis factor (TNF)-α concentrations were also investigated in the flap tissue samples. A PNA of 72.7 ± 7.5 (95% confidence interval [CI]: 64.8-80.6) was captured in the control group. Following treatment with CBD 0.3, 1, 5, and 10 mg/kg, a dose-dependent effect was observed with PNAs of 51.0 ± 10.0 (95% CI: 40.5-61.5; p <0.05), 15.4 ± 5.8 (95% CI: 9.3-21.5; p <0.001), 37.1 ± 10.2 (95% CI: 26.3-47.8; p <0.001), and 46.4 ± 14.0 (95% CI: 31.7-61.1; p <0.001), respectively. Histopathologically, tissues enhanced significantly. Besides, CB2 expression surged remarkably, IL-1β and TNF-α concentrations decreased considerably after treatment with CBD of 1 mg/kg compared with the control (p <0.05 and <0.001, respectively). Administering SR144528 reversed the favorable effects of CBD of 1 mg/kg, both macroscopically and microscopically. Pretreatment with CBD of 1 mg/kg improved SFS considerably in rats and exerted desirable anti-inflammatory effects which were possibly mediated by CB2 receptors.

Effects of Preconditioning With Transcutaneous Electrical Nerve Stimulation Monitored by Infrared Thermography on the Survival of Pedicled Perforator Flaps in a Rat Model.

Pedicled perforator partial or complete necrosis with a rate of 13.7%. This study was undertaken to test whether preconditioning with transcutaneous electrical nerve stimulation (TENS) monitored by infrared thermography protect against partial necrosis by converting the choke anastomoses to the true anastomoses via inducing heme oxygenase-1 (HO-1) in a rat pedicled perforator flap model. Seventy-two Sprague-Dawley rats were randomly assigned to the control, the TENS, the TENS + SnPP (tin protoporphyrin; HO-1 activity inhibitor; 50 μmol/kg) and the TENS +0.9% saline groups. On the unilateral dorsum of the rats, a rectangular flap donor site of 11 × 3 cm was marked out, which contained three perforator angiosomes and two choke zones. On days 1, 3 and 4, 1 hour of TENS (biphasic pulses, 25 mA, 80 Hz, 200 μs) was applied to the flap donor sites, respectively. On day 5, after the flap donor sites were assessed by infrared thermography, the flaps were harvested based on the deep circumflex iliac artery perforator. Infrared thermography showed that the choke zones in the flap donor sites presented white in the TENS and the TENS +0.9% saline groups, whereas they presented red in the control and the TENS + SnPP groups. Postmortem arteriography showed that the number of arterioles across each choke zone significantly increased in the TENS and the TENS +0.9% saline groups compared with the control and the TENS + SnPP groups. Immunohistochemistry and western blot showed a significant increase in HO-1 in the choke zones after TENS preconditioning. The necrotic area percentage of the flaps was significantly decreased in the TENS (4.3% ± 2.6%) and the TENS +0.9% saline groups (4.5% ± 2.3%) compared with the control (24.8% ± 5.0%) ( P < 0.001); there was no significant difference between the TENS and the TENS + SnPP (24.4% ± 7.3%) groups. These data show that TENS preconditioning monitored by infrared thermography might be a promising strategy to prevent pedicled perforator flaps from partial necrosis.

Prevention of necrosis in ischemic skin flaps using hydrogel of Rhizophora mangle

INTRODUCTIONNecrosis in ischemic cutaneous flaps (ISF) is a type of surgical failure more feared among surgical complications. Currently, synthetic drugs are applied during the treatment of necrosis in ISF and although several substances show improvement in viability, some require application at high systemic doses, which can produce important side effects. Therefore, the search for natural substances with fewer side effects is constant. The use of medicinal plants that stimulate angiogenesis is commonly mentioned in previous studies and in this case Rhizophora mangle L. (R. mangle) highlights that among its main compounds have tannins and flavonoids that are very chemically reactive in various biological activities. This study aimed to associate a natural hydrogel to the 5% extract of R. mangle and to evaluate its potential in the prevention of tissue necrosis in distal portions of ISF in rats, using the model proposed by Macfarlane, et al. (1965). METHODSIschemic skin flaps were made in the thin dorsal skin area of 28 Wistar rats and divided into 4 groups, group A: received only saline, group B where the aqueous extract of R. mangle was applied, group C received the 1.5% hydrogel of xanthan gum (XG) + placebo and group D was applied the hydrogel associated with 5% R. mangle extract. Morphometric analyses of the areas of tissue necrosis were performed from photographic records using the software Photoshop® and ImageJ®. In addition, 5 photomicrographs were taken from each histological sample of each animal for histomorphometric analysis that obtained the count of fibroblasts and blood vessels. RESULTSThe mean percentage of necrotic areas was: group (A) – 50,66%, group (B) – 40,49%, group (C) – 37,44% and group (D) – 34,25%. The statistical analysis, using the Kruskal-Wallis test, showed a significant difference (p < 0.001).

Effect of pentoxifylline and α-tocopherol on medication-related osteonecrosis of the jaw in rats: Before and after dental extraction

ObjectiveEvaluate the effect of pentoxifylline and α-tocopherol administration in the prevention or treatment of medication-related jaw osteonecrosis (MRONJ). MethodologySixty Wistar rats were divided into three prevention (C-prev, BP-prev and BP/PT-prev) and three treatment groups (C-treat, BP-treat and BP/PT-treat), n = 10. The animals in the BP-prev, BP/PT-prev, BP-treat and BP/PT-treat groups received zoledronic acid (0.1 mg/kg) for 12 weeks, while the animals in the C-prev and C-treat groups received saline solution. At week 6, all animals underwent tooth extraction. Between week 5 and week 12, the BP/PT-prev group was treated with pentoxifylline (50 mg/kg/day) and α-tocopherol (80 mg/kg/day), with euthanasia at the end of week 12. The BP/PT-treat group received the same drug protocol, but it was performed between week 12 and week 16, with euthanasia at the end of week 16. Afterwards, the presence of osteonecrosis was evaluated by clinical analysis, radiographic and histological. ResultsBP/PT-treat group showed a reduction in the histological incidence of osteonecrosis by 50%, decrease the percentage of empty osteocyte gaps and the necrotic area, decrease the presence of bone sequestration and increase the number of osteocytes and alveolar blood flow (p < 0.05). However, BP/PT-prev group showed only a reduction in the necrotic area percentage when compared to BP-prev (p < 0.05). ConclusionsPentoxifylline and α-tocopherol administration before tooth extraction was not effective in preventing MRONJ. However, this drug protocol was able to reduce MRONJ manifestation when administrate after discontinuation of bisphosphonate, thus it can be considered as a viable strategy for the treatment of this pathological condition.

Role of podoplanin and Kupffer cells in liver injury after ischemia-reperfusion in mice.

To investigate the relationship between the intrahepatic expression of podoplanin (PDPN) and Kupffer cells (KCs) in ischemia-reperfusion (I/R) liver damage. C57Bl/6 mice were injected with 200µl of clodronate liposomes (macrophage depletion; MDP group) to deplete KCs or control liposomes (control group) via the ophthalmic vein plexus 24h prior to ischemia. Animals were subjected to 90min of partial hepatic ischemia (70%), followed by reperfusion, and were then killed at designated time points. Serum and liver tissues were harvested for further analyses. Serum ALT levels, mortality rates, and the percentage of necrotic area in liver sections were significantly higher in the MDP group than in the control group. PDPN was expressed in the lymphatic epithelium, interlobular bile duct epithelium, and in some hepatocytes in each group. Its expression in hepatocytes was down-regulated in the MDP group. The accumulation of platelets in the sinusoid was reduced 6h after I/R in the MDP group. Tissue HGF and IGF-1 levels decreased in the MDP group. These results suggest that KCs play a key role in the activation of platelets through direct contact with PDPN-positive hepatocytes in I/R livers.

Control and translocation of saflufenacil in fleabane (Conyza spp.) according to plant integrity

Efficient herbicide absorption and translocation, and satisfactory weed control can be affected by the site of herbicide application. However, during harvesting of crops of previous soybean sowing, the cutting process made by harvesters on the fleabane may generate a difficult management in pre sowing of the crop by limiting the leaf area of the absorption of the herbicide. Experiments were conducted to evaluate the control efficiency and translocation potential of saflufenacil in fleabane plants with different leaf and stem conditions. Experiment I was arranged in a 2x10 factorial scheme, with factor A corresponding to leaf integrity, and factor B corresponding to different levels of injury and saflufenacil application. Weed control was evaluated at 7, 14, and 21 days after herbicide treatment (DAT), and dry matter was evaluated at 21 DAT. Experiment II consisted of applying saflufenacil to different fleabane structures, where the percentage of necrotic area was evaluated at 1, 3, 5, and 7 DAT. Fleabane control was higher than 75% in all treatments with saflufenacil application, with greater control in plants previously defoliated. Saflufenacil application on 10 and 20 cm hairy fleabane plants was also efficient in all treatments. Saflufenacil application in old stem showed a larger necrotic area, while application in the site of the cutting resulted in a lower necrotic area. The main pathway for translocation of saflufenacil is via xylem and the stem proved to be the absorption element of the herbicide when leaf area is limited.

Protective effect of modafinil on skin flap survival in the experimental random-pattern skin flap model in rats: The role of ATP-sensitive potassium channels and nitric oxide pathway

Background The brain-stimulating agent modafinil acts through nitric oxide (NO) and adenosine triphosphate (ATP)-sensitive potassium (KATP) channels, involved in the skin flap survival (SFS). The main aim of this study was to investigate the efficacy of modafinil on SFS in rats through the involvement of NO pathway and KATP channels. Methods Using controlled experiment study design, we enrolled a sample of Wistar male rats. Different doses of modafinil (10, 25, 50, and 100 mg/kg) were injected intraperitoneally (i.p.) before the surgery. L-NAME (non-selective nitric oxide synthase [NOS] inhibitor), aminoguanidine (inducible NOS inhibitor), and 7-nitroindazole (neuronal NOS inhibitor) were administered prior to modafinil. The role of KATP channels was determined by coadministering glibenclamide (KATP channel blocker) or cromakalim (KATP channel opener) with modafinil. The predictor variables were administration of different doses of modafinil, and the coadministration of modafinil with L-NAME, aminoguanidine, 7-nitroindazole, glibenclamide, and cromakalim. The main outcome variables included the percentage of necrotic area (PNA) in flap tissues, histopathological results, vascular endothelial growth factor (VEGF) immunohistochemical (IHC) staining, and nitrite concentrations. Appropriate statistics were computed considering p-value ≤ 0.05 significant. Results Modafinil 25 mg/kg was the most effective dose (PNA: 26 [95% CI: 19–33]) vs. control (PNA: 81 [95% CI: 71–92]) (p< 0.001). All NOS inhibitors significantly reversed the protective effect of modafinil (p< 0.001). Non-effective dose of cromakalim had a synergistic effect with the sub-effective dose of modafinil (10 mg/kg), while glibenclamide reversed the effect of modafinil 25 mg/kg (p< 0.001). Conclusions Modafinil increases SFS mediated by NO pathway and KATP channels, which could therefore be a target to improve SFS. The brain-stimulating agent modafinil acts through nitric oxide (NO) and adenosine triphosphate (ATP)-sensitive potassium (KATP) channels, involved in the skin flap survival (SFS). The main aim of this study was to investigate the efficacy of modafinil on SFS in rats through the involvement of NO pathway and KATP channels. Using controlled experiment study design, we enrolled a sample of Wistar male rats. Different doses of modafinil (10, 25, 50, and 100 mg/kg) were injected intraperitoneally (i.p.) before the surgery. L-NAME (non-selective nitric oxide synthase [NOS] inhibitor), aminoguanidine (inducible NOS inhibitor), and 7-nitroindazole (neuronal NOS inhibitor) were administered prior to modafinil. The role of KATP channels was determined by coadministering glibenclamide (KATP channel blocker) or cromakalim (KATP channel opener) with modafinil. The predictor variables were administration of different doses of modafinil, and the coadministration of modafinil with L-NAME, aminoguanidine, 7-nitroindazole, glibenclamide, and cromakalim. The main outcome variables included the percentage of necrotic area (PNA) in flap tissues, histopathological results, vascular endothelial growth factor (VEGF) immunohistochemical (IHC) staining, and nitrite concentrations. Appropriate statistics were computed considering p-value ≤ 0.05 significant. Modafinil 25 mg/kg was the most effective dose (PNA: 26 [95% CI: 19–33]) vs. control (PNA: 81 [95% CI: 71–92]) (p< 0.001). All NOS inhibitors significantly reversed the protective effect of modafinil (p< 0.001). Non-effective dose of cromakalim had a synergistic effect with the sub-effective dose of modafinil (10 mg/kg), while glibenclamide reversed the effect of modafinil 25 mg/kg (p< 0.001). Modafinil increases SFS mediated by NO pathway and KATP channels, which could therefore be a target to improve SFS.

Comparison of embolic effect between water‐in‐oil emulsion and microspheres in transarterial embolization for rat hepatocellular carcinoma model

To compare two different embolic materials, water-in-oil (W/O) emulsion followed by gelatin particles and microspheres in transarterial embolization (TAE), using a rat hepatocellular carcinoma model. Twenty rats bearing N1S1 cells were divided into the W/O emulsion group and Microsphere group. Water-in-oil emulsion was created by a glass membrane emulsification device. The tumor vascularity was measured by contrast-enhanced ultrasonography 24h before and 10min and 48h after TAE. Tumor necrosis, hepatic infarction ratio surrounding the tumor, and locations of the embolic materials 48h after TAE were assessed. The changes of serum liver enzymes were also evaluated. Statistical significance was determined by using either the Mann-Whitney U-test or Fisher's exact test. The tumor vascularity 48h after TAE was significantly higher in the Microsphere group (20.1 vs. 3.76%, P = 0.016). The overflow of Lipiodol into the portal veins surrounding the tumor was seen, whereas microspheres were seen only in the artery. The percentage of necrotic area and complete response ratio in the W/O emulsion group was significantly higher (99.9 vs. 87.6%, P = 0.029 and 87.5 vs. 28.6%, P = 0.041, respectively). Serum aspartate aminotransferase and serum alanine aminotransferase levels 48h after TAE were significantly higher in the W/O emulsion group (P < 0.01). The embolization using W/O emulsion followed by gelatin particles showed stronger antitumor effects with the occlusion of both the tumor feeding artery and the portal vein compared with microspheres, which occluded only the arteries.

Digital Planimetry: Is it a Possible Standard Method for Evaluation and Measurement of Ulcer Healing?

Introduction - The measurement of ulcers and the reduction of their surface, as an indicator of closure, are frequent procedures in the clinical and research fields. A medical record with digital support could provide greater precision and optimize the therapeutic approach. The primary aim of the study was to analyze the agreement in the measurement of lesions and presence of necrotic area between digital planimetry (MOWA® and HELCOS® systems) and manual planimetry (VISITRAK®), the latter being our reference pattern. The secondary aim was to analyze the degree of inter and intra-observer agreement. Methods - Design: Precision study of diagnostic method. Sample: 44 patients with chronic ulcers of different etiology. Variables studied: Total area (cm2) and percentage of necrotic area. Statistical analysis: Non-parametric correlation test (correlation coefficient r), Bland-Altman diagram and concordance and correlation index (CCI). A qualified nurse from our staff took photographs with the same camera, parallel to the lesion, using the same brightness and a calibrated reference point (2.5 cm2). Two observers independently measured the different variables with the three systems and one of them repeated the procedure in the following 24 hours. Results - The CCI for the total area between VISITRAK® / MOWA® was 0.89 (0.848- 0.92) and between VISITRAK® / HELCOS® was 0.79 (0.72- 0.85). The interobserver and intraobserver CCI (total area) was 0.99 (0.998- 0.996) and 0.76 (0.60- 0.86) for MOWA®, respectively. The interobserver and intraobserver CCI (total area) was 0.56 (0.35- 0.72) and 0.60 (0.35- 0.72) for HELCOS®, respectively. There was a low concordance between the different systems in the area of necrosis compared to the standard reference (VISITRAK®): r 0.58 and 0.23 for MOWA® and HELCOS®. Conclusion: The systems of digital image analysis present a high precision for the measurement of total ulcer area compared to the manual methods. However, the differentiation between the components of necrosis, granulation tissue and fibrin depends on the conditions of brightness and software parameters.

Pathologic complete response to chemoembolization improves survival outcomes after curative surgery for hepatocellular carcinoma: predictive factors of response

BackgroundWe identified the predictive factors and prognostic significance of transarterial chemoembolization (TACE) for achieving pathologic complete response (pCR) before curative surgery for hepatocellular carcinoma (HCC) in hepatitis B–endemic areas. MethodsAmong 753 HCC patients treated with surgery, 124 patients underwent preoperative TACE before liver resection (LR), and 166 before liver transplantation (LT) between 2005 and 2016. Overall survival (OS) and recurrence-free survival (RFS) were analyzed. Pathologic response (PR) was defined as the mean percentage of necrotic area, and pCR was defined as the absence of viable tumor. ResultsA total of 34 (27%) and 38 (23%) patients had pCR before LR and LT, respectively. Alpha-fetoprotein (AFP) < 100 ng/mL and single tumor were significant preoperative predictors of pCR. OS and RFS were significantly improved in patients with pCR or a PR ≥ 90%, but not in patients with PR ≥ 50% after LR and LT. On multivariate analyses, PR ≥ 90% remained an independent predictor of better OS and RFS in LR and LT groups. ConclusionOverall, our data clearly demonstrate that pCR predicts favorable prognosis after curative surgery for HCC, and predictors of pCR are AFP <100 ng/mL and single tumor.

Computational study of necrotic areas in rat liver tissue treated with photodynamic therapy

BackgroundPhotodynamic therapy (PDT) is an alternative treatment method for liver metastatic cancer worth exploring. MethodsThis study implements a computational model of metastatic rat liver tissue subjected to superficial irradiation, after administration of 5,10,15,20-Tetrakis(3-hydroxyphenyl)chlorine (mTHPC). Spatial and temporal distributions of fundamental PDT dosimetric parameters are presented, along with calculation of necrotic distance and necrotic area percentage. Moreover, an algorithm able to calculate the minimum irradiation time needed in order to achieve various values of necrotic depth is coded. ResultsThe intratissue distributions show that light penetration depth is approximately 1.5 mm for all fluence rate (φ) values in direction of z axis. Moreover, necrosis at r axis (horizontal axis) extends outside beam's geometrical edges at distance equal up to 55.3% of its radius. It is also noticed that both φ and concentration of ground-state photosensitizer ([S0]) can increase the necrotic distance, in a steeper manner at lower [S0] values. The irradiation time needed in order to achieve various values of necrotic depth is independent of φ for the upper tumor layers but is greater in orders of magnitude for deeper lying layers and low φ values. ConclusionsIncreasing light fluence rate appears to be a more productive method than increasing photosensitizer concentration for inducing necrosis, especially in larger tumors. Finally, our results show that high φ values are necessary in order to maintain clinically applicable irradiation times.

Effect of cilostazol in experimental model of degloving injuries in rat limbs.

To evaluate the effect of the cilostazol on the evolution of partially avulsed flaps, using experimental model of cutaneous degloving in rat limbs. A controlled and randomized experimental study was carried out in which the blood flow and the percentage of flap necrosis were evaluated. We compared the study group, which received cilostazol, and the control group, which received enteral saline solution in the postoperative period. The blood flow in the flap was evaluated through Laser Doppler flowmetry, and a planimetry using the IMAGE J® software was employed for the calculation of the area of necrosis. Enteral administration of cilostazol was associated with a higher mean blood flow in all regions of the flap, with a statistically significant difference in the proximal and middle regions (p<0.001) and a lower percentage of necrotic area in the flap (p<0.001). Postoperative enteral administration of cilostazol increased blood flow and decreased the total area of necrosis of avulsed cutaneous flaps of rat limbs.

Photobiomodulation laser and pulsed electrical field increase the viability of the musculocutaneous flap in diabetic rats.

The purpose of this study is to investigate the effect of pulsed electrical field (PEF) and photobiomodulation laser (PBM) on the viability of the TRAM flap in diabetic rats. Fifty Wistar rats were divided into five homogeneous groups: Group 1-control; Group 2-diabetics; Group 3-diabetics + PEF; Group 4-diabetic + laser 660nm, 10J/cm2, 0.27J; Group 5-diabetic + laser 660nm, 140J/cm2, 3.9J. The percentage of necrotic area was evaluated using software Image J®. The peripheral circulation of the flap was evaluated by infrared thermography FLIR T450sc (FLIR® Systems-Oregon USA). The thickness of the epidermis (haematoxylin-eosin), mast cell (toluidine blue), leukocytes, vascular endothelial growth factor, fibroblast and newly formed blood vessels were evaluated. For the statistical analysis, the Kruskal-Wallis test was applied followed by Dunn and ANOVA test followed by Tukey with critical level of 5% (p < 0.05). The PEF reduced the area of necrosis, decreased the leukocytes, increased the mast cells, increased the thickness of epidermis and increased newly formed blood vessels when it was compared to the untreated diabetic group of animals. Laser 660nm, fluence 140J/cm2 (3.9J) showed better results than the 10J/cm2 (0.27J) related to reduction of the area of necrosis and the number of leukocytes, increased mast cells, increased thickness of the epidermis, increased vascular endothelial growth factor, increased fibroblast growth factor and increase of newly formed blood vessels in diabetic animals. The laser and pulsed electrical field increase the viability of the musculocutaneous flap in diabetic rats.