scholarly journals Microcirculatory bed in reperfused flaps: modern possibilities for the correction of hemodynamic disorders (part III)

2021 ◽  
Vol 24 (2) ◽  
pp. 41-47
Author(s):  
V. F. Baytinger ◽  
K. V. Selianinov
Keyword(s):  
Blood Circulation ◽  
Perfusion Pressure ◽  
Free Flaps ◽  
Tissue Blood Flow ◽  
Peripheral Vascular ◽  
Microcirculatory Bed ◽  
Molecular Weights ◽  
Physiological Phenomenon ◽  
The Stability ◽  
Peripheral Blood Circulation

The paper presents an analysis of the literature data concerning the autoregulation of tissue blood flow in free axial flaps. Autoregulation of microcirculation is an extremely important physiological phenomenon that ensures the stability of peripheral blood circulation and adequate metabolism in organs and tissues, regardless of fluctuations in systolic blood pressure in the range of 80-160 mm Hg. The types of sludge and their origin are described. Technologies of elimination of erythrocyte aggregates (sludge) by using dextrans of different molecular weights and pentoxifylline are discussed. Controlling the duration of primary ischemia, maintaining adequate perfusion pressure in the replants of the limbs and in free flaps, as well as reducing the peripheral vascular resistance in them, will make it possible to level the disturbances in the autoregulation of microcirculation in the reperfused tissues, ensuring the stability of capillary pressure.

Acanthopanax senticosus Induces Vasorelaxation via Endothelial Nitric Oxide-Dependent and -Independent Pathways

Planta Medica ◽  
2019 ◽  
Vol 85 (13) ◽  
pp. 1080-1087 ◽  
Author(s):  
Yayoi Shiokawa ◽  
Shino Miyauchi-Wakuda ◽  
Satomi Kagota ◽  
Kana Maruyama-Fumoto ◽  
Shizuo Yamada ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Blood Pressure ◽  
Blood Flow ◽  
Peripheral Blood ◽  
Blood Circulation ◽  
Tissue Blood Flow ◽  
No Production ◽  
Organ Bath ◽  
Acanthopanax Senticosus ◽  
Peripheral Blood Circulation

AbstractAlthough Acanthopanax senticosus root extract (ASRE), a functional food used in Japan, improves peripheral blood circulation and exerts vasorelaxant effects in rats under healthy conditions, the underlying mechanisms currently remain unclear. Therefore, we investigated the mechanisms responsible for ASRE-induced relaxation in isolated thoracic aortas using organ bath techniques and examined whether ASRE affects systemic and peripheral circulation using a photoplethysmographic tail-cuff system and noncontact laser tissue blood flow meter in Wistar rats. Similar to acetylcholine (ACh), ASRE induced dose-dependent relaxation in aortas pre-contracted with phenylephrine; however, in contrast to ACh, ASRE-induced relaxation was partially inhibited by treatments with antagonists of nitric oxide (NO) synthase and soluble guanylyl cyclase as well as by endothelium removal. Contractile responses to phenylephrine or potassium chloride were observed in the presence of ASRE. The oral administration of ASRE (900 mg/kg/d for 1 wk) decreased systolic blood pressure in rats 3 h after the treatment and did not affect heart rate, tail blood flow, mass, or velocity; this decreasing effect was not observed on day 2. A 1-wk treatment with ASRE did not affect vasorelaxation in response to ASRE. These results demonstrate that ASRE induces vasorelaxation via endothelial NO production and an NO-independent pathway in rats. Based on these findings, positive impacts of ASRE on blood pressure and peripheral blood circulation cannot be expected under healthy conditions as the systemic effects of ASRE are temporary. Instead, caution is needed to prevent the occurrence of side effects (i.e., orthostatic dizziness) at the beginning of ASRE dosing.

Individual mechanisms underlying peripheral nerve damage when exposed to metallic mercury

2020 ◽  
Vol 60 (12) ◽  
pp. 918-924
Author(s):  
Dina V. Rusanova ◽  
Oleg L. Lakhman ◽  
Galina M. Bodienkova ◽  
Irina V. Kudaeva ◽  
Natalya G. Kuptsova
Keyword(s):  
Peripheral Nerve ◽  
Peripheral Nerves ◽  
Blood Circulation ◽  
The State ◽  
Contact Period ◽  
Peripheral Nerve Damage ◽  
Demyelinating Disorders ◽  
Peripheral Blood Circulation ◽  
Antibodies To Dna

Introduction. There is a lack of knowledge of the pathophysiological mechanisms that form peripheral nerve disorders in mercury lesions of professional origin. The study aims to reveal the mechanisms underlying peripheral nerve damage in the long-term post-contact period of chronic mercury intoxication (CMI). Materials and methods. Fifty-one people had the diagnosis of a long-term period of CMI. The post-contact period was 8.5±2.6 years. The authors compared the results with a control group of 26 healthy men who had no contact with toxic substances. Stimulating electroneuromyography was performed. We studied the body systems that could contribute to the formation of disorders in the peripheral nerves. Changes in peripheral hemodynamics were studied using reovasography. The content of autoantibodies, neuron-specific enolase, serotonin, histamine, catecholamines (epinephrine, dopamine), metanephrine, and neurotrophin-3 was reviewed. The content of ceruloplasmin, secondary products of lipid peroxidation processes, reduced glutathione, the activity of superoxide dismutase and the content of nitric oxide levels were determined. Results. The study established pathogenetic structural links of peripheral nerve disorders. The autoimmune process's role was to increase the range of antibodies to the MAG protein and increase the level of antibodies to DNA. Violations of elastic-tonic properties of peripheral vessels could be associated with the functional state of motor axons. The increased content of neurotransmitters is related to the state of peripheral blood circulation; the most pronounced changes were on the legs, which could contribute to the occurrence and maintenance of vasoconstriction. The role of oxidative stress in the formation of demyelinating disorders in patients' peripheral nerves in the long-term period of CRI is possible. Conclusion. Neuroimmunological processes has an essential role in the development of peripheral nerve demyelination was shown, which consists in an increase in the content of antibodies to the MAG protein expressed on Schwann cells of peripheral nerves and in an increase in the level of antibodies to DNA involved in the formation of demyelinating changes when exposed to metallic mercury. The revealed pathological changes in the state of the peripheral blood circulation, characterized by a violation of the vessels' elastic-tonic properties, leading to demyelination of motor axons in patients in the long-term period of CMI. The increased content of neurotransmitters in the examined is of great importance in the state of peripheral circulation. Pronounced changes in blood circulation are established on the lower extremities, which may be associated with the predominance of α-adrenergic receptors in the arterial bed and may contribute to the occurrence and maintenance of vasoconstriction in the legs. The relationship between changes in indicators of oxidative stress, consisting of a decrease in the value of superoxide dismutase and reduced glutathione, and the formation of demyelinating disorders of peripheral nerves in patients in the long-term period of CMI has been proved.

scholarly journals Risk factors for pegylated liposomal doxorubicin-induced moderate to severe hand-foot syndrome in breast cancer patients: assessment of baseline clinical parameters

BMC Cancer ◽  
2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Guohua Liang ◽  
Wenjie Ma ◽  
Yanfang Zhao ◽  
Eryu Liu ◽  
Xiaoyu Shan ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Risk Factors ◽  
Prediction Model ◽  
Cancer Patients ◽  
Blood Circulation ◽  
Pegylated Liposomal Doxorubicin ◽  
Dose Intensity ◽  
Breast Cancer Patients ◽  
Hand Foot Syndrome ◽  
Peripheral Blood Circulation

Abstract Background Hand-foot syndrome (HFS) is a side effect of skin related to pegylated liposomal doxorubicin (PLD) application. Moderate to severe hand-foot syndrome (MSHFS) might have a serious impact on patients’ quality of life and treatment. However, information on risk factors for the development of MSHFS is still limited. To analyze the risk factors for PLD-induced MSHFS in breast cancer patients and constructed a logistic regression prediction model. Methods We conducted a retrospective analysis of breast cancer patients who were treated with a PLD regimen in the Tumor Hospital of Harbin Medical University from January 2017 to August 2019. A total of 26 factors were collected from electronic medical records. Patients were divided into MSHFS (HFS > grade 1) and NMHFS (HFS ≤ grade 1) groups according to the NCI classification. Statistical analysis of these factors and the construction of a logistic regression prediction model based on risk factors. Results A total of 44.7% (206/461) of patients developed MSHFS. The BMI, dose intensity, and baseline Alanine aminotransferase (ALT) and Aspartate aminotransferase (AST) levels in the MSHFS group, as well as good peripheral blood circulation, excessive sweat excretion, history of gallstones, and tumour- and HER2-positive percentages, were all higher than those in the NMHFS group (P < 0.05). The model for predicting the occurrence of MSHFS was P = 1/1 + exp. (11.138–0.110*BMI-0.234*dose intensity-0.018*baseline ALT+ 0.025*baseline AST-1.225*gallstone history-0.681* peripheral blood circulation-1.073*sweat excretion-0.364*with or without tumor-0.680*HER-2). The accuracy of the model was 72.5%, AUC = 0.791, and Hosmer-Lemeshow fit test P = 0.114 > 0.05. Conclusions Nearly half of the patients developed MSHFS. The constructed prediction model may be valuable for predicting the occurrence of MSHFS in patients.

scholarly journals Investigation of Silicon Nanoparticle-Polystyrene Hybrids

2019 ◽  
Vol 2 (2) ◽  
pp. 49-50
Author(s):  
Madihah Khan ◽  
Alyxandra Thiessen ◽  
I Teng Cheong ◽  
Sarah Milliken ◽  
Jonathan G. C. Veinot
Keyword(s):  
Silicon Nanoparticles ◽  
In Situ Polymerization ◽  
Toxic Substance ◽  
Homogeneous Mixture ◽  
Silicon Nanoparticle ◽  
Molecular Weights ◽  
Abundant Element ◽  
The Stability ◽  
Led Lights

Current LED lights are created with quantum dots made of metals like selenium, tellurium, and cadmium which can be toxic. Silicon is used as a non-toxic substance and is the second most abundant element in the earth's crust. When silicon is prepared at a nanometer size, unique luminesce optical properties emerge that can be tuned using sized surface chemistry. Therefore, silicon nanoparticles can be used as an alternative emitter for LED lights. To produce hydride-terminated silicon nanoparticles we must synthesize the particles. Hydrogen silsesquioxane (HSQ) is processed at 1100 °C for one hour causing Si to cluster and form a SiO2 matrix, also known as the composite. The composite is then manually crushed in ethanol. The solution is further ground using glass beads, then filtered to get the composite powder. The final step is the HF etching. The hydride-terminated particles are then functionalized using three different methods to synthesize silicon nanoparticle-polystyrene hybrids, which determine the magnitude of luminosity and the quality of the hybrids. We spin coat each method and results were analyzed. Method 1 uses heat to functionalize hydride-terminated silicon nanoparticles with styrene. This process also causes styrene to attach to styrene to form a polystyrene chain. Method 1 gave a homogeneous mixture which yielded a consistent, bright and homogenous film. In method 2, dodecyl-terminated silicon nanoparticles are mixed with premade polystyrene. While this method gave better control of the amount of silicon nanoparticles inside the polymer hybrid, a homogeneous mixture was not created due to the different structures of polystyrene and dodecyl chains. Method 3 has dodecyl-terminated silicon with in-situ styrene polymerization. It generated a homogeneous mixture. The in-situ polymerization stabilizes the particles, allowing for brighter luminescence. Because of the stability and lower molecular weight, the mixture was easier to dissolve. We concluded that the different methods resulted in different polymer molecular weights and this created distinct properties between the polymer hybrids when spin-coating.    

Vasodilator drugs and peripheral vascular disease

1972 ◽  
Vol 10 (23) ◽  
pp. 91-92
Keyword(s):  
Blood Flow ◽  
Vascular Disease ◽  
Peripheral Vascular Disease ◽  
Intermittent Claudication ◽  
Placebo Effect ◽  
Perfusion Pressure ◽  
Symptomatic Improvement ◽  
Peripheral Vascular ◽  
Vasodilator Drug ◽  
Local Accumulation

Many drugs are recommended for the treatment of peripheral vascular disease but evidence for their usefulness is conflicting, mainly because the drug responses are difficult to assess. For instance a symptom such as intermittent claudication may fluctuate spontaneously1 and is also particularly susceptible to a placebo effect.2 Objective criteria may also mislead, for an increase in the blood flow in the ischaemic limb during exercise does not necessarily correlate with symptomatic improvement,3 and in healthy limbs the response to a drug may be quite different from that in a diseased one. In the diseased limb, for instance, a vasodilator drug may not increase the blood flow above that already produced by the local accumulation of metabolites,4 and furthermore any drug that causes widespread dilatation in normal vessels may reduce the perfusion pressure and thus the flow to the ischaemic limb,5 or may shunt blood away from ischaemic zones towards normal areas.

Improvement in ischemic myocardial blood flow following a new calcium antagonist

1980 ◽  
Vol 239 (2) ◽  
pp. H163-H171 ◽  
Author(s):  
S. R. Jolly ◽  
G. J. Gross
Keyword(s):  
Blood Flow ◽  
Perfusion Pressure ◽  
Aortic Pressure ◽  
Contractile Force ◽  
Tissue Blood Flow ◽  
Coronary Pressure ◽  
Ischemic Tissue ◽  
High Doses ◽  
Mean Aortic Pressure ◽  
Aortic Perfusion

The effect of FR 7534, a new dihydropyridine CA2+ antagonist, nitroglycerin, and dipyridamole have been compared on coronary collateral function in pentobarbital-anesthetized open-chest dogs following acute ligation of the left anterior descending coronary artery. Measurements of tissue blood flow using radioactive microspheres were made 60 min postligation after low and high doses of each drug and at the higher dose with methoxamine added to to return mean aortic pressure. FR 7534 treatment increased subepicardial, subendocardial, and transmural tissue flow by 100% in the central ischemic zone when perfusion pressure was controlled by methoxamine. Nitroglycerin also increased ischemic tissue flow, but to a lesser degree, 18% transmurally. Dipyridamole produced no significant change. Tissue flow in normal myocardium was similarly increased by FR 7534 and dipyridamole but slightly reduced by nitroglycerin. FR 7534 and nitroglycerin also increased retrograde coronary pressure when aortic presure was maintained constant. FR 7534, but not nitroglycerin, increased ischemic contractile force. In this model, FR 7534 may produce greater effects than nitroglycerin in increasing blood supply to ischemic myocardium delivered by endogenous collaterals especially when aortic perfusion pressure was controlled.

scholarly journals The composition of peptidochitodextrins from sarcophagid puparial cases

1971 ◽  
Vol 125 (3) ◽  
pp. 703-716 ◽  
Author(s):  
H. Lipke ◽  
T. Geoghegan
Keyword(s):  
Molecular Weight ◽  
Amino Acid ◽  
Protein Complex ◽  
Covalent Bonds ◽  
Aromatic Residues ◽  
Similar Molecular Weight ◽  
X Ray ◽  
Molecular Weights ◽  
Physical Interactions ◽  
The Stability

1. N-Bromosuccinimide cleaved proteins and pigments from fly puparia, increasing the chitin:protein ratio from 0.5 to 1.5. The product afforded subfractions (ratio 5:1) of molecular weights of 1200 and 1600 devoid of aromatic residues and N-terminal β-alanine, direct aryl links between polysaccharide chains being discounted. 2. The chitin–protein complex decreased in molecular weight when treated with Pronase, which suggested polypeptide bridges within the native chitin micelle. The limit dextrins generated by chitinase were mixtures of unsubstituted dextrins and peptidylated oligosaccharides, with the former predominating. 3. Peptidochitodextrins of similar molecular weight but markedly different solubility were prepared, which were indistinguishable with respect to amino acid, glucosamine, acetyl, X-ray or infrared characteristics. It is suggested that physical interactions contribute to the stability of the integument in addition to the covalent bonds that form during sclerotization.

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