Prevention and Management of Filler Induced Iatrogenic Stroke of the Eye [Formula: see text].

In the past few decades, minimally-invasive esthetic treatments and the use of injectable Hyaluronic Acid Gels and other filling agents to treat facial esthetics have increased dramatically. Although extremely rare, a filler can cause ocular and orbital ischemia by retrograde flow from the ophthalmic artery when injected in any of the anastomosis of the face. Once filler reaches the central retinal artery, blindness is inevitable, and no treatment is effective. While the risk of blindness happening with any filler injection is rare, the life-altering irreversible consequence of a procedure that was anticipated to be simple and beautifying is a reality that each injector must be prepared for with every injection. The parameters associated with an iatrogenic stroke of the eye are the site of injection, the injection technique, patient characteristics, and the material injected. Understanding the interplay of each of these variables might help us reduce the possibility of blindness during the injection of a soft-tissue cosmetic filler. Here, we explore the causes of Hyaluronic Acid Gels Filler embolic phenomena, review the natural course of the process, and discuss appropriate immediate interventions. We also (1) propose an education plan for injectors and describe how to carry out a focused ophthalmologic examination and procedural activities for a referral to an ophthalmologist, (2) outline steps to prevent emboli during filler injection, and (3) how to manage and support a patient with a sudden loss of vision during or immediately after a Hyaluronic Acid Gels filler treatment.

Conus Medullaris Infarction Involving the Paraspinal Muscles and Nerve Roots.

Spinal cord infarctions account for less than 1% of all strokes. The segmental artery supplies the spinal cord, vertebrae, nerve roots, and paraspinal muscles. To our knowledge, this is the first case of spinal cord infarction involving multiple distinct infarcts at various sites, including the lumbar vertebrae, conus medullaris, dorsal thoracolumbar spinal cord, paraspinal muscles, and nerve roots.

High-dose enoxaparin in the treatment of abdominal angiostrongyliasis in Swiss mice.

Abdominal angiostrongyliasis (AA) is caused by Angiostrongylus costaricensis, which inhabits mesenteric arteries. There is no drug treatment for AA, and since intestinal infarction due to thrombi is one of the main complications of the disease, the use of anticoagulants may be a treatment option. Thus, we aimed to assess the effect of high doses of enoxaparin on the prevention of ischaemic intestinal lesions and on the survival of mice infected with A. costaricensis. Twenty-four mice were infected with L3 of A. costaricensis and divided equally into two groups: Group 1, control treated with placebo, and Group 2, treated daily with enoxaparin (2.5 mg/kg) for 50 days. All mice were subjected to necropsy and histological analysis. The results from gross and microscopic assessments showed no variation in the prevalence of lesions between the groups. An analysis was also performed among survivors and non-survivors, showing that animals that died often presented lesions, such as granulation tissue in the serosa, and intestinal infarction and adhesion. The mortality rate did not vary between the enoxaparin-treated and control groups. Thus, we showed that high doses of enoxaparin have no protective effect against AA, as the survival rates and lesions of mice did not vary between the treated and control groups. Considering that the use of prophylactic doses was also shown to be ineffective in a previous study, we do not recommend the use of enoxaparin for AA treatment.

Thrombolytic treatment in a patient with antiphospholipid syndrome : APS developing renal infarction.

Antiphospholipid syndrome (APS), a leading entity in acquired thrombophilia, is characterized by recurrent thrombosis, morbidity in pregnancy and presence of antiphospholipid antibodies (APA). Although the etiopathogenesis is unclear, APA against negatively charged phospholipids and phospholipid-protein complexes are held responsible for the clinical picture. In case of acute thrombosis due to APS, thrombolytic therapy is not a commonly administered treatment option. Here, we present a case with acute thrombosis in the left renal artery showing partial response to thrombolytic therapy.

Maternal floor infarction: management of an underrecognized pathology.

Maternal floor infarction is a relatively rare condition characterized clinically by severe early onset fetal growth restriction with features of uteroplacental insufficiency. It has a very high recurrence rate and carries a significant risk or fetal demise. Pathological characteristics include massive and diffuse fibrin deposition along the decidua basalis and the perivillous space of the basal plate. We present a case of recurrent maternal floor infarction and propose diagnostic clues as well as potential therapeutic options.

Application of Guglielmi detachable coils in embolization of iatrogenic renal hemorrhage.

BACKGROUND: This study aims to evaluate the application value of Guglielmi detachable coils (GDCs) in the embolization of iatrogenic renal hemorrhage. METHODS: Twelve iatrogenic renal hemorrhage patients who failed conservative treatment were randomly treated by superselective transcatheter arterial embolization (TAE) with GDCs, gelatin sponge, and microcoil embolization, respectively. The efficacy of treatment, damage to renal function, and renal infarct size were observed. RESULTS: Embolizations were successful in all patients on the first attempt. Hematuria disappeared completely after the surgery; no recurrence of hemorrhage and no abnormal renal function were observed during the follow-up period. Postoperative angiography revealed that patients treated with GDC embolization had minimum renal infarcts. CONCLUSIONS: In summary, while superselective TAE provides a safe and effective therapy in patients with iatrogenic renal hemorrhage, the application of GDCs can better prevent the loss of normal renal tissue after embolization.

Improved infarction rates in fibroids after the introduction of contrast-enhanced ultrasound during uterine artery embolization.

BACKGROUND: In order to achieve sustained symptom control and minimize the risk of recurrence, uterine artery embolization (UAE) should aim at complete infarction of all fibroids. PURPOSE: To retrospectively evaluate the infarction rate of uterine fibroids in patients that had undergone uterine artery embolization (UAE) after the introduction of contrast-enhanced ultrasound (CEUS) during UAE procedures at our institution. MATERIAL AND METHODS: Thirty patients treated with UAE between February 2006 and August 2009 were included. MR images obtained before, at 3 months, and 12 months after the procedure were reviewed. We evaluated volume changes in dominant fibroids as well as the infarction rate of all fibroids in each patient. Clinical results were evaluated by reviewing the medical records. The study was approved by the institutional review board. RESULTS: CEUS was technically successfully performed during the UAE procedure in all patients. In five cases the endpoint of embolization was adjusted based on findings at CEUS. The mean volume shrinkage of dominant fibroids was 39.8% after 3 months and 59.8% after 12 months. There was complete infarction of all fibroid tissue in 97% of patients at 3 months and 96% at 12 months. No major complications were observed. CONCLUSION: After the introduction of CEUS during UAE procedures in our institution, high infarction rates were achieved.

Intraoperative Doppler and Duplex sonography in cerebral aneurysm surgery.

PURPOSE: The aim of open surgery of cerebral aneurysms is to minimise the risk of infarction due to poor position of a clip while still securing the aneurysm from rebleeding. Whilst digital subtraction angiography (DSA) remains the gold standard for precise evaluation of the result, its invasiveness, risk of thromboembolic infarction, availability and time-consumption pose a significant limitation, and overall it is rarely used. The goal of the present study was to analyse the feasibility of intraoperative B-mode Duplex ultrasound in combination with Doppler sonography (DDS) to evaluate this issue. METHODS: A total of 44 aneurysms in 40 patients were investigated intraoperatively via B-mode and power Duplex sonography after clip positioning in a prospective setting. Data were then compared to postoperative angiography. RESULTS: In 38 cases DDS allowed for visualisation of aneurysm localisation, neck and diameter, as well as associated vessels, in accordance to preoperative DSA. This was confirmed by Duplex sonography in 94.7%. Further evaluation of each associated vessel after clip positioning was then enabled by Doppler sonography in 84.8%. Visualisation in terms of B-mode sonography was not successful in six cases due to multiple clips. CONCLUSION: DDS is an additional tool for immediate evaluation of clipping performance intraoperatively and can be used in simple cases with reliable results. In six cases Doppler-/Duplex-sonography did not illustrate the clipping result sufficiently. It is not yet able to replace DSA in aneurysms with complex configuration.

Transitory activation of AMPK at reperfusion protects the ischaemic-reperfused rat myocardium against infarction.

PURPOSE: AMPK plays a crucial role in the regulation of the energy metabolism of the heart. During ischaemia, AMPK activation is a known adaptative prosurvival mechanism that helps to maintain the energy levels of the myocardium. However, it still remains unclear if activation of AMPK during reperfusion is beneficial for the heart. Two known AMPK activators (metformin and AICAR) were used to verify the hypothesis that a transitory activation of AMPK at reperfusion may exert cardioprotection, as reflected in a reduction in myocardial infarct size. METHODS: Perfused rat hearts were subjected to 35 min ischaemia and 120 min reperfusion. Metformin (50 microM) or AICAR (0.5 mM) were added for 15 min at the onset of reperfusion alone or with Compound C (CC, 10 microM), an AMPK inhibitor. Infarct size and alpha-AMPK phosphorylation were measured. RESULTS: Metformin significantly reduced infarct size from 47.8 +/- 1.7% in control to 31.4 +/- 2.9%, an effect abolished by CC when the drugs were given concomitantly. Similarly, AICAR also induced a significant reduction in infarct size to 32.3 +/- 4.8%, an effect also abrogated by CC. However, metformin's protection was not abolished if CC was administered later in reperfusion. In addition, alpha-AMPK phosphorylation was significantly increased in the metformin treated group during the initial 30 min of reperfusion. CONCLUSIONS: Our data demonstrated that, in our ex vivo model of myocardial ischaemia-reperfusion injury, AMPK activation in early reperfusion is associated with a reduction in infarct size.

MiR-135b protects cardiomyocytes from infarction through restraining the NLRP3/caspase-1/IL-1ß pathway.

BACKGROUND: Myocardial infarction (MI) is the most common cause of cardiovascular morbidity and mortality worldwide. Despite the identification of many pathogenic genes associated with MI, the underlying molecular mechanisms remain poorly understood. MicroRNAs (miRNAs, miRs), which regulate target genes at the post-transcriptional level, play a significant role in the regulation of cardiovascular diseases such as MI. Pyroptosis is a caspase-1-dependent pro-inflammatory programmed cell death (PCD) mechanism. The role of pyroptosis in several diseases associated with various miRNAs has been studied extensively. Meanwhile, the role of NOD-like receptor-containing pyrin 3 (NLRP3)/caspase-1/interleukin-1ß (IL-1ß) pathway in cardiac diseases has also been more recognized. METHODS: We established a mice MI model which ligated with the left anterior descending coronary artery and a cardiomyocytes injury model treated by hydrogen peroxide (H2O2) to detect the expressions of miR-135b and NLRP3/caspase-1/IL-1ß pathway. Then miR-135b mimic, agomir-135b, and α-MHC-miR-135b transgenic mice were used to evaluate the effects of miR-135b overexpression. RESULT: We demonstrated that miR-135b was downregulated after cardiomyocytes injury both in vivo and in vitro. Pyroptosis pathway was also activated. MiR-135b overexpression remarkably restored impaired cardiac function and attenuated the upregulation of NLRP3/caspase-1/IL-1ß pathway. CONCLUSIONS: The present findings shed light on the protective role of miR-135b in MI mediated by the inhibition of the NLRP3/caspase-1/IL-1ß pathway.

A case of upper lip necrosis after cosmetic injection of hyaluronic acid soft-tissue filler-Does capillary infarction play a role in the development of vascular compromise, and what are the implications?

Facial rejuvenation with injectable filler substances is a frequently applied outpatient procedure. However, light, moderate, and even severe complications may occur. A case of tissue necrosis at the upper lip after injection of highly cross-linked hyaluronic acid together with the following salvage procedure is presented here. We discuss this complication with respect to relevant anatomy and physicochemical properties of the filler substance and review the recommendations given in literature for decreasing the likelihood of such an adverse event.

Na+/H+ exchange inhibitor cariporide attenuates skeletal muscle infarction when administered before ischemia or reperfusion.

Administration of Na(+)/H(+) exchange isoform-1 (NHE-1) inhibitors before ischemia has been shown to attenuate myocardial infarction in several animal models of ischemia-reperfusion injury. However, controversy still exists as to the efficacy of NHE-1 inhibitors in protection of myocardial infarction when administered at the onset of reperfusion. Furthermore, the efficacy of NHE-1 inhibition in protection of skeletal muscle from infarction (necrosis) has not been studied. This information has potential clinical applications in prevention or salvage of skeletal muscle from ischemia-reperfusion injury in elective and trauma reconstructive surgery. The objective of this research project is to test our hypothesis that the NHE-1 inhibitor cariporide is effective in protection of skeletal muscle from infarction when administered at the onset of sustained ischemia or reperfusion and to study the mechanism of action of cariporide. In our studies, we observed that intravenous administration of cariporide 10 min before ischemia (1 or 3 mg/kg) or reperfusion (3 mg/kg) significantly reduced infarction in pig latissimus dorsi muscle flaps compared with the control, when these muscle flaps were subjected to 4 h of ischemia and 48 h of reperfusion (P < 0.05; n = 5 pigs/group). Both preischemic and postischemic cariporide treatment (3 mg/kg) induced a significant decrease in muscle myeloperoxidase activity and mitochondrial-free Ca(2+) content and a significant increase in muscle ATP content within 2 h of reperfusion (P < 0.05; n = 4 pigs/group). Preischemic and postischemic cariporide treatment (3 mg/kg) also significantly inhibited muscle NHE-1 protein expression within 2 h of reperfusion after 4 h of ischemia, compared with the control (P < 0.05; n = 3 pigs/group). These observations support our hypothesis that cariporide attenuates skeletal muscle infarction when administered at the onset of ischemia or reperfusion, and the mechanism involves attenuation of neutrophil accumulation and mitochondrial-free Ca(2+) overload and preservation of ATP synthesis in the early stage of reperfusion.

A new intercostal artery management strategy for thoracoabdominal aortic aneurysm repair.

OBJECTIVE: The purpose of this study is to describe a new approach for addressing the intraoperative management of intercostal arteries during thoracoabdominal aortic aneurysm (TAAA) repair, using preoperative spinal MRA for detection of intercostal arteries supplying the anterior spinal artery. METHODS: Patients undergoing TAAA repair from August 2005 to September 2007 were included. Spinal artery MRA was performed to identify the anterior spinal artery, the artery of Adamkiewicz, and its major intercostal source artery (SA-AAK). Intraoperative spinal cord protection was carried out using standard techniques. Important intercostal arteries were either preserved or reimplanted as a button patch after removing aortic clamps. Demographic and perioperative data were collected for review. Analysis was performed with Fisher's exact test or Student's t-test, where applicable, using SAS ver. 8.0 (Cary, NC). RESULTS: Spinal artery MRA was performed in 27 patients. The SA-AAK was identified in 85% of preoperative studies. Open or endovascular repair was performed in 74% and 26% of patients, respectively. The SA-AAK was preserved or reimplanted in 13 (65%) of patients who underwent open repair. A mean of 1.67 (range 1-3) intercostal arteries were reimplanted. All patients undergoing endovascular repair necessitated coverage of the SA-AAK. No patient developed immediate or delayed paraplegia. Longer mean operative times in the reimplanted cohort were not statistically significant (330 versus 245 min, P = 0.1). CONCLUSION: The SA-AAK identified by MRA can be preserved or safely reimplanted after TAAA repair. Further study is warranted to determine if selective intercostal reimplantation can reduce the risk of immediate or delayed paraplegia.

Influence of canal preparation depth on the incidence of femoral medullary infarction with Zurich Cementless Canine Total Hip arthroplasty.

OBJECTIVE: To determine the incidence of femoral medullary infarction after modifying the depth of femoral reaming and filing when performing total hip replacement (THR) using the Zurich Cementless Total Hip Replacement system (ZCTHR). STUDY DESIGN: Case series. ANIMALS: Dogs (n=31) that had ZCTHR (34). METHODS: Thirty-one dogs (34 THR) had ZCTHR (May 2003-September 2006) and with >1 year radiographic (craniocaudal, mediolateral views) follow-up after THR were evaluated for the presence of femoral medullary infarcts. Incidence was compared with a previous study performed before the technique modification. RESULTS: Femoral medullary infarction occurred in 1 femur (2.9%; dog <18 months at THR) compared with 19.5% before the technique change, a significant decrease (P<.001). CONCLUSION: Limiting the depth of reaming and filing of the medullary canal resulted in a significant decrease in the incidence of femoral medullary infarction. CLINICAL RELEVANCE: Depth of reaming and filing the medullary canal should be limited when performing THR using the ZCTHR.

Femoral medullary infarction prevalence with the Zurich Cementless Canine Total Hip arthroplasty.

OBJECTIVE: To document the prevalence of femoral medullary infarction associated with the Zurich Cementless Total Hip Replacement (ZCTHR) system in dogs. STUDY DESIGN: Case series. ANIMALS: Dogs (n=35) with 41 ZCTHR implants. METHODS: Medical records (February 1999-December 2002) were reviewed for dogs that had ZCTHR and at least 1 year follow-up with radiographic evaluation. Thirty-five dogs (41 ZCTHR) met the inclusion criteria. Femoral morphologic data, implant to bone relationships, and medullary infarcts were recorded. Data were analyzed for associations between infarct occurrence and morphologic details and dog characteristics. RESULTS: Eight of 41 femurs had radiographic evidence of infarcts (19.5%). Dogs with infarcts were significantly younger (mean [+/-SD] age, 18.5+/-5.2 months) compared with those without infarction (mean age, 44.4+/-5.6 months; P=.027). None of the other variables were significantly different between dogs with and without infarcts. Three femurs with infarcts ultimately developed stem loosening. CONCLUSION: A higher prevalence of femoral medullary infarcts was identified with ZCTHR compared with incidence reported for other total hip systems. Younger dogs were more likely to develop infarction. CLINICAL RELEVANCE: Femoral infarction appears to be associated with stem loosening. Adjustments in surgical technique or delaying surgery beyond 18 months of age may reduce incidence of infarction but needs further evaluation.

What's the remedy for the distal necrosis of DIEP flap, better venous drain or more arterial supply?

BACKGROUND: We developed a novel pedicled DIEP flap model in rat to explore the possible remedy for the distal necrosis of the flap. METHODS: A deep inferior epigastric perforator (DIEP) flap, based on the second right cranial perforator (P2) as the main pedicle, was elevated in 48 Sprague-Dawley rats. The rats were randomized into 4 groups: group I, the left P2 remaining intact as supercharging; group II, the left P2 artery alone kept as supercharging; group III, the left P2 vein alone kept as supercharging; group IV, no supercharging. Transcutaneous oxygen pressure (TcPO2) and transcutaneous carbon dioxide pressure (TcPCO2) were measured immediately after flap elevation, protein level of Hif-1a was measured 48 hours later, and flap survival was assessed 7 days postoperatively. RESULTS: Blockade of artery led to significantly lower TcPO2, higher TcPCO2, and higher expression level of Hif-1a in the distal side of the flap in group III and group IV, than those of group I and group II. At 7 days post surgery, significantly lower flap survival rates were observed in group III (81.9 ± 5.7%) and group IV (78.4 ± 6.5%), compared to observed in group I (97.2 ± 3.0%) and group II (94.2 ± 6.2%). CONCLUSIONS: It might be arterial insufficiency, not venous congestion, which mainly caused the distal necrosis of the DIEP flap in rat. Arterial instead of venous supercharging might be a more effective procedure that improves circulation to zone IV of the flap.

CARDIOPROTECTIVE ROLES OF THE CHINESE MEDICINAL FORMULA BAO-XIN-TANG ON ACUTE MYOCARDIAL INFARCTION IN RATS.

BACKGROUND: Bao-Xin-Tang (BXT) is a traditional Chinese medicinal formula used for the treatment of coronary heart disease and known to have favorable therapeutic benefits. The current study was designed to determine whether BXT has a cardioprotective role for acute myocardial infarction. The underlying mechanisms were also explored. MATERIALS AND METHODS: The Sprague-Dawley rat model of acute myocardial infarction was established by occluding the left anterior descending branch of the coronary artery. After a 3-h ischemic period, we determined the myocardial infarction size, inflammatory components, and antioxidant activities. RESULTS: The data showed that BXT could reduce the infarction size and lower the levels of C-reactive protein, interleukin-6, and myeloperoxidase, and increase the activities of superoxide dismutase and the anti-inflammatory cytokine, interleukin-10. These results indicate that administration of BXT, following acute myocardial infarction, could reduce infarct size. CONCLUSION: The effects of BXT may be related to its anti-inflammatory and anti-oxidative properties.

Validação de conteúdo: aplicativo móvel safe heart para monitoramento e identificação de risco de infarto / Validación de contenido: aplicación móvil safe heart para el seguimiento e identificación del riesgo de infarto / Content validation: safe heart mobile application for monitoring and identification of infarction risk

Objetivo verificar a validade de conteúdo do aplicativo móvel Safe Heart para monitoramento e identificação de risco de infarto. Método estudo de validação de conteúdo. Participaram do estudo 10 juízes. Foram avaliados 21 itens, por meio da escala de Likert. Para estimativa do grau de concordância, foi utilizado o cálculo do coeficiente alfa de Cronbach. Resultados a análise estatística com alpha de Cronbach 0,9573 consolidou o Safe Heart quanto à validade e à confiabilidade na consistência interna do conteúdo desenvolvido no aplicativo; os juízes apresentaram consistência válida nos itens observados. Conclusão a validade de conteúdo do aplicativo móvel Safe Heart foi aprovada para monitoramento e identificação de risco de infarto.

Objetivo verificar la validez de contenido de la aplicación móvil Safe Heart para el seguimiento e identificación del riesgo de infarto. Método estudio de validación de contenido. Diez jueces participaron en el estudio. Veintiún ítems fueron evaluados mediante la escala Likert. Para estimar el grado de concordancia, se calculó el coeficiente alfa de Cronbach. Resultados el análisis estadístico con Cronbach de alfa 0,9573 consolidó Safe Heart en cuanto a validez y confiabilidad en la consistencia interna del contenido desarrollado en la aplicación; los jueces presentaron consistencia válida en los ítems observados. Conclusión la validez de contenido de la aplicación móvil Safe Heart ha sido aprobada para el seguimiento e identificación del riesgo de infarto.

Objective to verify the content validity of the Safe Heart mobile app for monitoring and identification of infarction risk. Method content validation study. Ten judges participated in the study. Twenty-one items were evaluated using the Likert scale. To estimate the degree of agreement, Cronbach's alpha coefficient was calculated. Results Cronbach's alpha statistical analysis with 0.9573 consolidated Safe Heart regarding validity and reliability in the internal consistency of the content developed in the application; the judges presented valid consistency in the observed items. Conclusion the content validity of the Safe Heart mobile app has been approved for monitoring and identification of infarction risk.

Acute ischaemic preconditioning protects against skeletal muscle infarction in the pig.

OBJECTIVE: The aims were to investigate the efficacy of acute ischaemic preconditioning for protection of skeletal muscles against infarction and its effect on muscle blood flow and ischaemic muscle metabolism. METHODS: The efficacy of preconditioning was tested by subjecting pig latissimus dorsi and gracilis muscles to different numbers and durations of ischaemia/reperfusion cycles before 4 h of global ischaemia. Infarction was assessed at 48 h of reperfusion, using nitroblue tetrazolium dye. Blood flow in the latissimus dorsi was measured at the end of preconditioning and 1.5 and 3.0 h of reperfusion, using the radioactive microsphere (15 microns) technique. Muscle biopsies were taken from the latissimus dorsi before ischaemia, at the end of 2 and 4 h of ischaemia, and 1.5 h of reperfusion. RESULTS: At least three cycles of 10 min ischaemia and 10 min reperfusion were required for preconditioning of latissimus dorsi and gracilis muscles for protection against infarction. Preconditioning reduced the total infarct size by 44% and 62% in latissimus dorsi and gracilis muscles, respectively. Preconditioning did not affect preischaemia muscle blood flow but it reduced the muscle content (preischaemia reserve) of phosphocreatine and ATP and the muscle energy charge potential (ECP) by 13.5%*, 27.5%*, and 8%* (*P < 0.05), respectively. In spite of a lower preischaemia reserve of phosphocreatine and ATP, the muscle contents of phosphocreatine and ATP and muscle ECP were maintained higher and the lactate lower (*P < or = 0.05) in the preconditioned than in the non-preconditioned (control) muscles at the end of 4 h of ischaemia [phosphocreatine 8.0(SEM 0.4) v 3.2(0.3)*; ATP 9.8(0.7) v 7.8(0.3); ECP 0.72(0.02) v 0.66(0.01)*; lactate 115.4(8.6) v 160.5(11.8)* mumol.g-1 dry muscle]. The level of ATP and ECP also remained significantly higher and the level of lactate significantly lower in the preconditioned than in the non-preconditioned latissimus dorsi muscles at 1.5 h of reperfusion. Hyperaemia was seen in the preconditioned latissimus dorsi muscles at 1.5 h of reperfusion and it subsided by the end of 3h of reperfusion. CONCLUSIONS: The protective effect of preconditioning can be induced in pig skeletal muscle but at a higher threshold than reported previously in pig cardiac muscle (one cycle). Preconditioning of pig skeletal muscle is associated with a lower energy metabolism during sustained ischaemia. At the present time, it is not known if this energy sparing effect is a major mechanism of ischaemic preconditioning against infarction in skeletal muscles.

The neuroprotective mechanism of puerarin in the treatment of acute spinal ischemia-reperfusion injury is linked to cyclin-dependent kinase 5.

Puerarin is shown to exert a variety of pharmacological effects including neuroprotective properties. However, mechanisms of the action are not fully understood. This study was designed to explore the mechanism of puerarin in treatment of acute spinal ischemia-reperfusion injury in rats. Acute spinal ischemia-reperfusion injury was conducted by aortic occlusion in twenty-eight male Sprague-Dawley rats, weighting 230-250 g. The animals were randomly divided into four groups. In the animals with puerarin treatment, 50 mg/kg of puerarin was injected intraperitoneally after reperfusion, and followed by the same dose of injection every 24h for 2 days. In the animals with roscovitine pre-treatment, 30 mg/kg roscovitine was intravenously administrated 60 min before spinal ischemia started. After spinal ischemia for 60 min followed by 48 h of reperfusion, the motor function, spinal infarction volume, apoptosis indices and the activities of Cdk5 and p25 were examined. Acute spinal ischemia-reperfusion resulted in an injury of the spines associated with motor deficit, elevation of Cdk5 and p25 activities, and increase in the spinal apoptosis number and spinal infarction volume. Puerarin improved motor function associated with the decreased apoptosis number, spinal infarction volume, and Cdk5 and p25 activities. The present study indicated that reduction of spinal injury was associated with inhibition of Cdk5 and p25, and that inhibition of Cdk5 and p25 was one of the neuroprotective mechanisms in the puerarin treatment of acute ischemia/reperfusion-induced spinal injury in rats.