TGF-ß loaded exosome enhances ischemic wound healing in vitro and in vivo.

Rationale: With over seven million infections and $25 billion treatment cost, chronic ischemic wounds are one of the most serious complications in the United States. The controlled release of bioactive factor enriched exosome from finbrin gel was a promising strategy to promote wound healing. Methods: To address this unsolved problem, we developed clinical-grade platelets exosome product (PEP), which was incorporate with injectable surgical fibrin sealant (TISSEEL), to promote chronic wound healing and complete skin regeneration. The PEP characterization stimulated cellular activities and in vivo rabbit ischemic wound healing capacity of TISSEEL-PEP were performed and analyzed. Results: PEP, enriched with transforming growth factor beta (TGF-ß), possessed exosomal characteristics including exosome size, morphology, and typical markers including CD63, CD9, and ALG-2-interacting protein X (Alix). In vitro, PEP significantly promoted cell proliferation, migration, tube formation, as well as skin organoid formation. Topical treatment of ischemic wounds with TISSEEL-PEP promoted full-thickness healing with the reacquisition of hair follicles and sebaceous glands. Superior to untreated and TISSEEL-only treated controls, TISSEEL-PEP drove cutaneous healing associated with collagen synthesis and restoration of dermal architecture. Furthermore, PEP promoted epithelial and vascular cell activity enhancing angiogenesis to restore blood flow and mature skin function. Transcriptome deconvolution of TISSEEL-PEP versus TISSEEL-only treated wounds prioritized regenerative pathways encompassing neovascularization, matrix remodeling and tissue growth. Conclusion: This room-temperature stable, lyophilized exosome product is thus capable of delivering a bioactive transforming growth factor beta to drive regenerative events.

Arterial only anastomosis associated with modified Baudet technique in ear replantation: Case reports and literature review.

BACKGROUND: Total ear amputation is a relatively rare trauma with an absolute indication for surgical treatment. Numerous techniques for auricular reconstruction have been described. When local and general conditions allow microsurgical replantation, this must be the first choice. We propose the association of microsurgical techniques with some modification (modified Baudet technique) to obtain higher survival rate of the reimplanted stump. METHODS: This study included cases of 3 male patients with total ear amputation, the injuries and their mechanism (workplace accident) being identical. Chief complaints were pain, bleeding, important emotional impact due by an unaesthetic appearance. The established diagnosis was traumatic complete ear amputation (grade IV auricular injury according to Weerda classification). Microsurgical replantation was performed only with arteriorraphy, and no vein anastomosis. Cartilage incisions and skin excisions were made to enlarge the cartilage-recipient site contact area. Medicinal leeches were used to treat venous congestion, to which systemic anticoagulant therapy was added. RESULTS: The results showed the survival of the entire replanted segment in all cases, with good function and esthetical appearance. Patients were fully satisfied with the final outcome. CONCLUSION: Microsurgical replantation is the gold standard, for the surgical treatment of total ear amputation. We believe that cartilage incisions and the increased surface of contact between cartilage and recipient site has an adjuvant role in revascularization of the amputated stump (with only arterial anastomosis) and the use of hirudotherapy helps to relieve early venous congestion.

Successful microsurgical revascularization of an almost totally amputated ear lobe by horse bite.

Total or subtotal amputation of the external ear related to horse bite is an uncommon situation. In our case, we report successful microsurgical revascularization of almost totally amputated ear of a 75-year-old male patient caused by a horse bite.

Histological results of sclerotherapy, phototherapy, and pulsed 980-nm laser irradiation of the dorsal rabbit ear vein.

OBJECTIVE: To compare the histological changes occurring after three different treatment modalities for telangiectasias. MATERIALS AND METHODS: Thirty 16-week-old New Zealand white rabbits weighing 2.4-3.1 kg were enrolled in the study. The rabbits were divided into three groups. The group 1 received sclerotherapy, he group 2 received phototherapy, and group 3 received high-power diode laser treatments. All animals were treated on the right dorsal marginal ear vein. Biopsies were taken on days 1, 2, 7, and 30 post-treatment, and histopathogical evaluation was performed. RESULTS: Clinical and histological thrombosis occurred between days 1 and 7 in all groups. Superficial necrosis, neutrophil infiltration, and recanalization were mostly seen in group 3, whereas thrombosis was prominent in groups 1 and 2. CONCLUSIONS: All of the methods tested appear to have similar mechanisms of action, but had differing clinical and histological results. Phototherapy and laser treatment are non-invasive and do not require an exact, pinpoint technique, in contrast to sclerotherapy. However, sclerotherapy and phototherapy showed better results, especially with regard to recanalization.

The use of lipid emulsions for the i.v. administration of a new water soluble polyene antibiotic, SPK-843.

Venous tolerance of a new water soluble polyene antibiotic, SPK-843, in 5% glucose solution for infusion is low in laboratory animals. The use of Intralipid 10% emulsion was therefore proposed, in which the antibiotic remained chemically stable for at least 2 h in a mildly acid or nearly neutral environment and at concentrations of 0.1-0.5 mg/mL, producing no alterations in the emulsion structure. Tolerance was assessed through repeated infusions in the ear marginal vein of rabbits and was found much more satisfactory than the tolerance observed when the vehicle used was 5% glucose solution. The study of the effect of some variables (concentration, volume infused, dose per kg) on venous toxicity offered the possibility to plan optimal administration conditions of presumed therapeutic doses.

[The effects of dieda zhentong liquid on ear microcirculation of rabbit].

OBJECTIVE: To observe the effects of Dieda Zhentong Liquid (DDZTL) on ear microcirculation of rabbits. METHODS: With microcirculation apparatus, caliber of micrangium, velocity and volume of blood flow were detected in experimental groups. RESULTS: The volume of blood flow of DDZTL group without Chlorophytum laxum haven't an increase compared with that of the group without administering the medicinal liquid. Shexiang Shuhuo Essence group, Chlorophytum laxum group, high and low dose DDZTL group have an increase. CONCLUSION: DDZTL could improve ear microcirculation of rabbit. Chlorophytum laxum maybe play an important role in above-mentioned effect.

Cutaneous vasoconstriction with alerting stimuli in rabbits reflects a patterned redistribution of cardiac output.

1. In conscious rabbits, when alerting stimuli elicit vasoconstriction in the ear vascular bed, there is little or no associated change in cardiac output (CO), as measured by chronically implanted Doppler ultrasonic probes. 2. Local anaesthetic injected around the base of the ear substantially diminished the degree of the vasoconstriction elicited during responses. 3. Our results emphasize that selective cutaneous vasoconstriction, an integral part of the response to alerting stimuli in conscious animals, is part of a patterned redistribution of the CO, organized by the brain.

Sound stimulation-induced vasomotor reflex in the central artery of the rabbit ear.

Effects of sound stimulation on the central artery of the rabbit ear were studied as a somato-autonomic reflex. Vasoconstriction and dilatation, caused by metronome sound stimulation, were estimated from the temperature fluctuations in the central artery of the ear, measured by a thermistor. To enhance the detection of temperature rises, moderately high background levels of arterial tone were established by exposing the tips of the ears to water at a temperature of 10 degrees C or 5 degrees C, prior to sound stimulation. A fall in arterial temperature due to vasoconstriction was observed immediately after the start of the 1-min sound stimulation, with a subsequent temperature rise which overshot the original basal level due to vasodilatation. A positive correlation between the ear temperature before sound stimulation and the temperature fall (p < 0.01), and a negative correlation between the ear temperature and the temperature rise (p < 0.05) were obtained. The temperature fall was blocked by phenoxybenzamine (9 mg/kg, i.p., p < 0.01). The subsequent rise was not influenced by atropine (3 mg/kg, i.p.) or phenoxybenzamine, however, it was attenuated by hexamethonium (6 mg/kg, i.p., p < 0.05). The temperature fall at the beginning of sound stimulation was related to alpha-adrenergic mechanism. The subsequent temperature rise was thought to be related to parasympathetic mechanism, excluding cholinergic mechanism.

[Pharmacological action of 101-B hair regeneration extract on skin and hair in experimental animals].

Pharmacological action of 101-B hair regeneration extract (101-B) on skin and hair was studied in experimental animals. The results were as follows: (1) In normal rats, guinea pigs and rabbits the weight of regrown hairs in shaved area in 101-B group was significantly heavier than that in alcohol group. (2) Hair loss induced by oral administration of thallium carbonate 2 mg/kg every other day for 10 times was obviously prevented by topical treatment of 101-B. (3) Itching threshold to histamine or papain in guinea pig was elevated after using of 101-B topically. (4) The diameter of skin ulcer caused by intradermal injection of adriamycin in rats was diminished in 101-B group. (5) Observation in skin microcirculation in mice indicated that both normal skin microcirculation and disturbed microcirculation induced by endotoxin were improved with administration of 101-B. Above experimental results provided preliminary evidence for clinical use of 101-B.

[Effect of electroacupuncture on peripheral microcirculation in acute experimental arthritic rats].

This paper reports the effect of electroacupuncture (EA) on peripheral microcirculation in 12 acute experimental arthritic rats and 6 healthy rats. The results showed that after EA an obvious improvement in footback-microcirculation of acute experimental arthritic rats appeared, namely, the disturbance of microcirculation on the area of pathological changes was alleviated. The auricular microcirculation was strengthened as well. There were no obvious changes of peripheral microcirculation in healthy rats after EA. That indicates EA has therapeutic effects of promoting blood circulation and reducing extravasated blood, antiphlogosis and detumescence on the area of pathological changes in acute experimental arthritic rat.

Impact of ischemia on tissue oxygenation and wound healing: improvement by vasoactive medication.

The influence of vasoactive medication on tissue oxygenation and wound healing was investigated in the ear model of the hairless mouse. Ischemia was induced to the ears by ligating 2 of the 3 main vessel bundels and verified by measurements of tcpO2. Reduced tissue oxygenation was followed by a prolongation of the time required for complete healing of standardized wounds. Treatment with the vasoactive drug Buflomedil (3 mg/kg/day iv.) resulted in enhanced recovery of the tissue from reduced oxygenation and likewise reversed the adverse effects of ischemia on wound healing. These results warrant the use of the drug in patients suffering from delayed wound healing due to peripheral arterial disease.

Effect of corticosteroid administration in ischemia--ischemic injury.

In order to study the preservation of ischemic tissue, an in vivo end-artery model was designed using the rabbit ear. Ear surface-area necrosis and ear edema were quantitatively evaluated for 14 postoperative days in a total of 107 rabbits. The LD50 of ischemic injury was determined by effecting 8, 10, and 12 hours of circulatory arrest. Using a 12-hour ischemic interval in this model, methylprednisolone decreased edema formation (p less than 0.01) and dramatically halted the progression of ischemic injury to necrosis (p less than 0.05) when administered within 5 hours after the onset of ischemia and continued for 3 postoperative days. A single perioperative dose of methylprednisolone was ineffective in decreasing edema formation and preserving tissue. Administration of steroids greater than 5 hours after the onset of ischemia was similarly ineffective even when administered for 3 postoperative days.

Vasodilator effects of cepharanthine, a biscoclaurine alkaloid, on cutaneous microcirculation in the rabbit.

Cutaneous microcirculatory responses to intravenous administration of cepharanthine (CT), a biscoclaurine alkaloid, isolated from Stephania cepharantha, were studied in a transparent round chamber installed in a rabbit ear, under conscious conditions. Vital-microscopic observations were made visually with a microscope-closed TV system and microphotoelectric plethysmography. Following the CT administration in doses of 1.0 and 3.0 mg/kg, an enhancement of rhythmic perfusion of microvascular blood due to vasomotion was developed for a period of 1 h or longer, although no appreciable change was observed following CT administration at 10.0 mg/kg. The microvascular dilator effect of CT appeared to have no direct association with systemic hemodynamics, based on the additional measurements of heart rate, blood pressure, carotid blood flow and auricular arterial blood flow.

Effects of acupuncture needle application upon cutaneous microcirculation of rabbit ear lobe.

Microcirculatory effects of the application of an acupuncture needle (32-gauge, silver) to the back, corresponding to Geshu (B17) in human beings, were studied in vivo by microscope, using a transparent ear chamber in conscious rabbits. Although no striking findings were obtained during the needle application for a period of 30 minutes, it was clearly observed that the microvascular blood flow increases gradually in parallel with augmenting spontaneous rhythmic fluctuation of the vessel diameter, namely vasomotion, throughout a continuous observation period longer than 2 hours following release from the needle application. Diameters of arterioles and venules at the full-dilating phases of vasomotion reached levels higher than 200% and 250% of the initial values just before application of the needle, respectively. The clinical efficacy of acupuncture was suggested to be explained at least in part by the increased rhythmic microvascular blood flow in parallel with vasomotion, from the physiological point of view based on the previous investigations.

Electrical responses of smooth muscle cells of the rabbit ear artery to adenosine triphosphate.

Ionophoretic application of ATP to smooth muscle cells of the rabbit ear artery produced rapid depolarization of the membrane and, in the case of large doses of ATP, spike potentials or slow oscillatory potentials. The ATP response desensitized rapidly, and required over 70 s for recovery. When the intervals between repetitive application of ATP were shorter than 70 s, the amplitudes of the ATP responses successively decreased. Ejection of ATP with increasing intensities of current (10-15% of the first) was required to produce successively increasing amplitudes of ATP responses. Repetitive stimulation of perivascular nerves (at intervals of less than 10 s) evoked increasing amplitude of excitatory junction potentials (e.j.p.s). Quinidine (over 5 X 10(-5) M) inhibited and theophylline (over 5 X 10(-4) M) enhanced the ATP response, with associated depolarization or hyperpolarization of the membrane, respectively. Cocaine (over 10(-6) M) depolarized the membrane and enhanced the ATP response. Phentolamine reduced the amplitude of the ATP response with no change in the membrane potential, only when the concentration was extremely high (over 10(-4) M). These all therefore appear to represent non-specific interactions with the effects of ATP. Bath application of ATP depolarized the membrane dose dependently and, at concentrations over 5 X 10(-7) M, produced spike potentials. The amplitude of electrotonic potentials decreased during the ATP-induced depolarization, thereby suggesting an increase in ionic conductance of the membrane. ADP depolarized the membrane, the effect being weaker than that of ATP. Both AMP and adenosine hyperpolarized the membrane. The results provide evidence that in the rabbit ear artery, the e.j.p. could be mimicked by ATP. ATP can however only account for the fast e.j.p. if it is released in increasing amounts with successive nerve discharges. Reported blocking agents for ATP receptors did not block the response to ATP in this tissue.

[Comparative study of the laws governing cutaneous blood flow in the thermoneutral zone]. / Sravnitel'nye issledovaniia zakonov upravleniia kozhnym krovotokom v termoneitral'noi zone.

A simplified model of the rabbit thermoregulatory system in the thermoneutral zone revealed three principles of the skin blood flow control. The temperature fluctuations in the thermoneutral zone could only be obtained in case of the on-off response of the control.

Responses of isolated canine intermediate auricular arteries to 5-hydroxytryptamine and methysergide.

The responses of the isolated canine intermediate auricular arteries to 5-hydroxytryptamine (5-HT), methysergide, norepinephrine (NE) and potassium chloride (KCl) were examined by means of the 'cannula inserting' method. 5-HT produced dose-dependent vasoconstriction more potently than did NE. The effect was blocked by methysergide, i.e. a small dose of methysergide competitively inhibited the 5-HT-induced effect, and a large amount of methysergide inhibited it non-competitively. The 5-HT-induced constriction was slightly but significantly suppressed by phentolamine in doses which markedly blocked NE-induced effects. KCl-induced effects were not significantly affected by methysergide and phentolamine treatment. Methysergide induced vasoconstriction by itself in about half out of all preparations. In cases in which methysergide induced vasoconstriction, the dose-response curves were bell-shaped and the constriction became smaller with large doses. At small doses, methysergide induced reproducible vasoconstriction but at large doses it readily caused tachyphylaxis. The methysergide-induced constriction was not blocked by 1 microgram of phentolamine which inhibited NE-induced constriction. It is concluded that the canine intermediate auricular artery is very sensitive to 5-HT and methysergide, and that the action of 5-HT may partially involve alpha-adrenergic mechanisms.

Muscarinic receptor inhibition and other effects of pancuronium in the rabbit ear artery preparation.

The effect of pancuronium in the rabbit ear artery was investigated in order to measure the inhibition it produces at the prejunctional muscarinic receptor on sympathetic nerve endings in this tissue. Pancuronium (0.1-0.2 mmol/l) produced an enhancement of responses to transmural electrical stimulation but this effect was absent in experiments conducted in the presence of cocaine (10 mumol/l) suggesting that an inhibition of the uptake1 mechanism occurs with pancuronium in this tissue. Pancuronium (10 mumol/l) in the presence of cocaine (10 mumol/l) and yohimbine (1 mumol/l) caused a small transient increase in resting output of tritium from arteries preincubated with 3H-noradrenaline but did not affect stimulated output of tritium nor the perfusion pressure in perfused preparations. Pancuronium in the presence of cocaine or cocaine plus yohimbine caused a parallel shift of the concentration-response curve for the inhibitory effect of carbachol (CCh) on the increase in perfusion pressure induced by nervous stimulation. An Arunlakshana-Schild plot of the data was linear but the slopes of 0.92 and 0.95 respectively, were significantly different from unity (P less than 0.05). The calculated pKB value suggests that pancuronium has a different affinity for prejunctional muscarinic receptors on sympathetic nerve endings in this tissue compared to that previously reported in cardiac or ileal smooth muscle.