Ischemia Research Papers - Academia.edu (original) (raw)

The objective of this study was to assess midterm functional status, wound healing, and in-hospital resource use among a prospective cohort of patients treated in a tertiary hospital, multidisciplinary Center for Limb Preservation. Data... more

The objective of this study was to assess midterm functional status, wound healing, and in-hospital resource use among a prospective cohort of patients treated in a tertiary hospital, multidisciplinary Center for Limb Preservation. Data were prospectively gathered on all consecutive admissions to the Center for Limb Preservation from July 2013 to October 2014 with follow-up data collection through January 2016. Limbs were staged using the Society for Vascular Surgery Wound, Ischemia, and foot Infection (WIfI) threatened limb classification scheme at the time of hospital admission. Patients with nonatherosclerotic vascular disorders, acute limb ischemia, and trauma were excluded. The cohort included 128 patients with 157 threatened limbs; 8 limbs with unstageable disease were excluded. Mean age (±standard deviation [SD]) was 66 (±13) years, and median follow-up duration (interquartile range) was 395 (80-635) days. Fifty percent (n = 64/128) of patients were readmitted at least once, ...

Autophagy is an intracellular bulk degradation process for elimination of damaged macromolecules and organelles. In the past decades, the scientific community has gained increasingly detailed understanding of the role of autophagy in... more

Autophagy is an intracellular bulk degradation process for elimination of damaged macromolecules and organelles. In the past decades, the scientific community has gained increasingly detailed understanding of the role of autophagy in myocardial homeostasis, although still many controversies remain. In the ischemic myocardium, autophagy appears to be beneficial for survival, whereas upon reperfusion the process may induce cell death. However, the overall effect of autophagy seems to depend on the duration and intensity of stress, as along with the extent of autophagy within myocardial tissue. Reperfusion of an ischemic heart maybe harmful, but it is an essential process for myocardial survival. One of the major adverse consequences of reperfusion is the occurrence of ventricular fibrillation (VF). In the present study, we investigated the possible connection between autophagy and VF. Isolated mouse hearts were subjected to ischemia/reperfusion (I/R) and divided into two groups based on the development of VF at the beginning of reperfusion. Western blot analysis was conducted for autophagy-associated proteins LC3B, ATG-5, ATG-7, ATG-12, Bcl-2 and Beclin-1 proteins. Significantly higher level of Beclin-1 and LC3B-II/LC3B-I ratio (both definitive autophagy biomarkers) was observed in the fibrillated myocardium, versus tissue from the nonfibrillated hearts. Interestingly, although Bcl-2 is a major regulator of Beclin-1, level of this protein was not significantly altered in tissue from fibrillated, versus non-fibrillated hearts. Moreover, Atg7 expression showed a trend, albeit nonsignificant, towards elevation in fibrillated versus non-fibrillated hearts. Results of the present investigation demonstrate a possible link between VF and autophagy. Studies by authors of this report to evaluate potential etiologic relationships between the two processes are ongoing.

The Neuromodulation Appropriateness Consensus Committee (NACC) of the International Neuromodulation Society (INS) evaluated evidence regarding the safety and efficacy of neurostimulation to treat chronic pain, chronic critical limb... more

The Neuromodulation Appropriateness Consensus Committee (NACC) of the International Neuromodulation Society (INS) evaluated evidence regarding the safety and efficacy of neurostimulation to treat chronic pain, chronic critical limb ischemia, and refractory angina and recommended appropriate clinical applications. The NACC used literature reviews, expert opinion, clinical experience, and individual research. Authors consulted the Practice Parameters for the Use of Spinal Cord Stimulation in the Treatment of Neuropathic Pain (2006), systematic reviews (1984 to 2013), and prospective and randomized controlled trials (2005 to 2013) identified through PubMed, EMBASE, and Google Scholar. Neurostimulation is relatively safe because of its minimally invasive and reversible characteristics. Comparison with medical management is difficult, as patients considered for neurostimulation have failed conservative management. Unlike alternative therapies, neurostimulation is not associated with medi...

To demonstrate the utility of 12-lead Holter monitoring underwater. A Holter monitor, recording a 12-lead electrocardiogram (ECG) underwater, was applied to 16 pre-trained volunteer scuba divers (13 males and three females). Dive... more

To demonstrate the utility of 12-lead Holter monitoring underwater. A Holter monitor, recording a 12-lead electrocardiogram (ECG) underwater, was applied to 16 pre-trained volunteer scuba divers (13 males and three females). Dive computers were synchronized with the Holter recorder to correlate the ECG tracings with diving events. Our main objective was to demonstrate the utility of recording over a period of time a good quality 12-lead ECG underwater. The ECGs were analyzed for heart rate (HR), arrhythmias, conduction abnormalities and ischaemic events in relation to various stages of diving as follows: baseline, pre diving, diving, and post diving. The ECG tracings were of good quality with minimal artefacts. Analysis of variance (ANOVA) demonstrated a significant difference in HR during the various diving stages (P < 0.0001). Other recorded ECG abnormalities included supraventricular ectopic beats (four cases), ventricular ectopic beats (eight cases) and ventricular couplets (...

Somatotopic distribution of motor cortex and sensory fibers is theoretically fully understood. We present a case of stroke, mimicking peripheral palsy, with finger paralysis attributed to cortical lesion. The patient's brain MRI may be... more

Somatotopic distribution of motor cortex and sensory fibers is theoretically fully understood. We present a case of stroke, mimicking peripheral palsy, with finger paralysis attributed to cortical lesion. The patient's brain MRI may be useful to further understand the somatotopic representation of fingers in precentral and postcentral gyrus.

Organ malperfusion is a serious complication of acute type A aortic dissection. Management and outcome of malperfusion has been discussed in this study. Between November 1994 and May 2003, 118 patients with acute type A aortic dissections... more

Organ malperfusion is a serious complication of acute type A aortic dissection. Management and outcome of malperfusion has been discussed in this study. Between November 1994 and May 2003, 118 patients with acute type A aortic dissections were operated. Fifty-seven patients (48.3%) were complicated with organ malperfusion, which is considered as group I. Seventy-three ischemic events were seen in 57 patients with organ malperfusion. Patients in group I were divided into four subgroups according to affected organ system including limb (38 events), coronary (9 events), renal (2 events), visceral (9 events), and cerebral (15 events) ischemia. Sixty-one patients without organ malperfusion constitute group II. The hospital mortality rate was 42.1% (24 of 57) in patients with malperfusion, 14.75% (9 of 61) in group II (p = 0.001), and 27.9% (33 of 118) in all patients. Postoperative complications such as mediastinal hemorrhage, low cardiac output, gastrointestinal system complications, acute renal failure, and multiple organ failure were higher in group I. Mesenteric and limb ischemia associated with high mortality. Multivariate analysis reveals that visceral malperfusion is the strongest predictor of postoperative mortality (odds ratio: 25.09, p = 0.000). Isolated coronary malperfusion had the lowest mortality (one patient, 16.6%) among the patients with organ malperfusion. Acute type A aortic dissections with organ malperfusion has higher postoperative mortality and morbidity. Immediate aortic repair is our management strategy in patients with limb, coronary, and neurological malperfusion. To reduce the extremely high mortality with mesenteric malperfusion, new strategies should be investigated such as surgical delay with interventional procedures.

We investigated prospectively in 128 patients (140 eyes) the role of six routine clinical tests in the differentiation of ischemic central retinal vein occlusion (CRVO) from non-ischemic CRVO during its early acute phase. There were... more

We investigated prospectively in 128 patients (140 eyes) the role of six routine clinical tests in the differentiation of ischemic central retinal vein occlusion (CRVO) from non-ischemic CRVO during its early acute phase. There were fourfunctional tests [visual acuity, visual fields, relative afferent pupillary defect (RAPID), electroretinography (ERG)] and twomorphologic tests (ophthalmoscopy and fluorescein fundus angiography). We found that none of the six tests had 100% sensitivity and specificity in such a differentiation during the early, acute phase, so that no one test can be considered a “gold standard”; however, combined information from all six is almost always reliable. Overall, the four functional tests proved far superior to the two morphologic tests in differentiating ischemic from non-ischemic CRVO: RAPID was most reliable in uniocular CRVO (with a normal fellow eye), followed closely by ERG in all cases; combined information from RAPID and ERG differentiated 97% of cases; perimetry was the next most reliable, followed by visual acuity. The two morphologic tests performed worst; fluorescein angiography provided either no information at all on retinal capillary nonperfusion (in at least one-third of the eyes during the early, acute phase) because of multiple limitations, or sometimes provided misleading information. Ophthalmoscopic appearance is the least reliable, most misleading parameter.

The treatment of inguinal hernia has changed considerably over the past 15 years. We reviewed the preclinical and clinical literature to find out the effect of inguinal hernia surgery on male fertility because it has been suggested that... more

The treatment of inguinal hernia has changed considerably over the past 15 years. We reviewed the preclinical and clinical literature to find out the effect of inguinal hernia surgery on male fertility because it has been suggested that hernia surgery may impair testicular function and male fertility. A search on Embase, MEDLINE, and the Cochrane Library was performed to find related articles. Animal models show substantial effects of hernia repair on the structures in the spermatic cord, which is more pronounced in mesh repairs. Although the number of studies and the included numbers of patients were limited, clinical studies indicate that these potential adverse effects do not seem to have a clinical impact on male fertility in humans with inguinal hernias. Future clinical studies, preferably with bilateral patients, are necessary to investigate the clinical relevance of the effects of inguinal hernia and hernia surgery on male fertility.

Ascorbate (vitamin C) is a vital antioxidant molecule in the brain. However, it also has a number of other important functions, participating as a co-factor in several enzyme reactions including catecholamine synthesis, collagen... more

Ascorbate (vitamin C) is a vital antioxidant molecule in the brain. However, it also has a number of other important functions, participating as a co-factor in several enzyme reactions including catecholamine synthesis, collagen production and regulation of HIF-1α. Ascorbate is transported into the brain and neurons via the Sodium-dependent Vitamin C Transporter-2 (SVCT2), which causes accumulation of ascorbate within cells against a concentration gradient. Dehydroascorbic acid, the oxidized form of ascorbate, is transported via glucose transporters of the GLUT family. Once in cells, it is rapidly reduced to ascorbate. The highest concentrations of ascorbate in the body are found in the brain and neuroendocrine tissues such as adrenal, although the brain is the most difficult organ to deplete of ascorbate. Combined with regional asymmetry in ascorbate distribution within different brain areas, these facts suggest an important role for ascorbate in the brain. Ascorbate is proposed as a neuromodulator of glutamatergic, dopaminergic, cholinergic and GABAergic transmission and related behaviors. Neurodegenerative diseases typically involve high levels of oxidative stress and thus ascorbate has been posited to have potential therapeutic roles against ischemic stroke, Alzheimer's disease, Parkinson's disease and Huntingdon's disease.

Diabetic foot wounds affect an estimated 15% of all patients with diabetes. These wounds are typically multifactorial in origin. Neuropathy of the foot and impaired wound healing are frequently associated with peripheral arterial... more

Diabetic foot wounds affect an estimated 15% of all patients with diabetes. These wounds are typically multifactorial in origin. Neuropathy of the foot and impaired wound healing are frequently associated with peripheral arterial occlusive disease. These factors combine to contribute to the development of foot ulcers. Successful wound healing and limb salvage require prompt recognition and treatment. Assessment of arterial perfusion is imperative and may be accomplished by a combination of physical examination and noninvasive vascular laboratory studies. When associated with significant ischemia, diabetic foot ulcers require arterial revascularization to achieve wound healing.

Blood vessel growth in adult organisms involves the following two fundamental processes: angiogenesis, the proliferation and extension of capillary networks; and arteriogenesis, the growth of functional arteries. We provide a protocol for... more

Blood vessel growth in adult organisms involves the following two fundamental processes: angiogenesis, the proliferation and extension of capillary networks; and arteriogenesis, the growth of functional arteries. We provide a protocol for the evaluation of postnatal arteriogenesis and angiogenesis in a mouse model of hind-limb ischemia. Surgical ligation of the femoral artery at a specific site triggers arteriogenesis of small, pre-existing collateral arteries into functional conduit vessels proximally and ischemic angiogenesis distally. The vascular response to hind-limb ischemia can be readily evaluated by laser Doppler-based perfusion measurements, histological quantification of arteriogenesis and angiogenesis or whole-mount visualization of arteries in limb muscles. Depending on the experimental design, the protocol takes between 4 and 29 d to complete; however, the net working time is about 2 d per mouse. The concurrent and specific analysis of postnatal angiogenesis and arteri...

Background and Objective: Stroke and cerebral ischemia are the second leading causes of death in the world. Currently, there are limited therapeutic interventions for patients with ischemia / reperfusion. This study was performed to... more

Background and Objective: Stroke and cerebral ischemia are the second leading causes of death in the world. Currently, there are limited therapeutic interventions for patients with ischemia / reperfusion. This study was performed to determine the protective effect of aerobic exercise and adenosine on changes in inflammation mediators after transient ischemia of common carotid arteries in male Wistar rats.
Methods: In this experimental study, fifty male Wistar rats were randomly allocated into to 5 groups: control, cerebral ischemic control, aerobic exercise + cerebral ischemia, adenosine + cerebral ischemia and aerobic exercise + adenosine + cerebral ischemia. Ischemia was performed by blocking the common carotid artery for 45 minutes after a period of exercise and injection of adenosine. Neuronal structure was examined by Nissel tissue staining. The expression of NGF and Glutamate genes were measured in CA1 region of hippocampal tissue samples.
Results: Cell death was increased in neurons in the CA1 region of the hippocampus in the ischemia / reperfusion group, While a significant reduction in cell death in the adenosine + ischemia / reperfusion and aerobic exercise + ischemia /reperfusion groups was due to adenosine administration and aerobic exercise (P<0.05). NGF and glutamate gene expression in the adenosine + ischemia/reperfusion and adenosine + aerobic exersice + ischemia/reperfusion groups significantly increased and reduced compared to the ischemia/reperfusion control, respectively (P<0.05).
Conclusion: Co-administration of adenosine combined with aerobic exercise increase the protective effect of aerobic exercise on improving the neuronal damage after ischemic / reperfusion.
Keywords: Ischemia [MeSH], Aerobic Exercise [MeSH], Adenosine [MeSH], Inflammation Mediators [MeSH],