Comparison of stiffness and interface pressure during rest and exercise among various arm sleeves

2010 ◽  
Vol 25 (4) ◽  
pp. 196-200 ◽  
Author(s):  
M Hirai ◽  
K Niimi ◽  
H Iwata ◽  
I Sugimoto ◽  
H Ishibashi ◽  
...  
Keyword(s):  
Pressure Difference ◽  
Pressure Transducer ◽  
Pressure Amplitude ◽  
Interface Pressure ◽  
Maximal Opening ◽  
High Level ◽  
Opening And Closing ◽  
Contraction And Relaxation ◽  
Rest And Exercise

Objectives To compare the interface pressure during rest and exercise among various kinds of arm sleeves. Methods The interface pressure underneath nine different arm sleeves was measured during 10 maximal opening and closing movements of fingers using a pressure transducer (Air Pack Type Analyser) in 16 healthy volunteers. Furthermore, in order to evaluate the characteristics of each arm sleeve, the extensibility, stiffness and thickness were determined in vitro by several apparatuses. Results There was a significant correlation between stiffness and extensibility. The stiffness was significantly correlated with the pressure difference between muscle contraction and relaxation during exercise. The higher the value of stiffness, the greater the pressure amplitude during exercise. Conclusion Short-stretch arm sleeves characterized with a high level stiffness, including thick round- and flat-knitted arm sleeves, are more beneficial for the augmentation of muscle pumping than long-stretch arm sleeves, in the same way as short-stretch bandages or stockings applied to the leg.

A comparison of interface pressure and stiffness between elastic stockings and bandages

2009 ◽  
Vol 24 (3) ◽  
pp. 120-124 ◽  
Author(s):  
M Hirai ◽  
K Niimi ◽  
H Iwata ◽  
I Sugimoto ◽  
H Ishibashi ◽  
...  
Keyword(s):  
Healthy Volunteers ◽  
Pressure Difference ◽  
Pressure Transducer ◽  
Stiffness Index ◽  
Static Stiffness ◽  
Interface Pressure ◽  
Elastic Stockings ◽  
Index Value ◽  
Contraction And Relaxation ◽  
Interface Pressures

Objectives To compare the interface pressure during posture changes and exercise between elastic stockings and bandages. Methods Using a pressure transducer (air pack-type analyzer), the interface pressures associated with three different elastic stockings and three different elastic bandages were measured during supine resting, standing and exercise in 15 healthy volunteers. Results Short-stretch bandages showed a significantly higher static stiffness index value, which is defined as the pressure difference between lying and standing, than long-stretch bandages and short-stretch stockings ( P < 0.001). Furthermore, short-stretch bandages showed a significantly greater pressure difference between muscle contraction and relaxation in both tip-toe and knee-bending exercises than long-stretch bandages and short-stretch stockings ( P < 0.001). Conclusion Short-stretch bandages can be expected to have more pronounced benefits for augmenting muscle pump than long-stretch bandages and short-stretch stockings.

Determinants of pressure exerted by medical compression stockings

Phlebologie ◽  
2007 ◽  
Vol 36 (05) ◽  
pp. 237-244 ◽  
Author(s):  
B. Lun ◽  
J. F. Uhl ◽  
Y. Bringer ◽  
W. Blättler
Keyword(s):  
Muscle Activation ◽  
Compression Stocking ◽  
Relative Role ◽  
Pressure Amplitude ◽  
Interface Pressure ◽  
Compression Stockings ◽  
In Situ Techniques ◽  
The One

Summary Objective: The force exerted on a limb by a medical compression stocking (MCS) is given by the properties of the yarn and the technique of knitting. The pressure determined by the manufacturer should be the one acting on the leg provided the stocking fits the leg shape. However, the interface pressure is governed by additional factors which act simultaneously in a poorly defined manner. We sorted out the different material- and patient-related components and assessed their relative role combining in vitro with in situ techniques. Design and method: The force exerted by the stockings was measured with the Zwick and Hosy dynamometers and the pressure exerted on the leg with the SIGaT instrument placed underneath the stockings at various sites. Leg circumference was determined with the Perometer and local radius calculated from computer tomographic slices and assessed with templates. Stockings exerting ankle pressures between 10 and 40 mmHg were tested. Subjects serving in the various experiments were selected from a pool of 28 healthy volunteers. Results: All stockings exerted the predefined pressure when measured at the stocking/leg-interface (in situ) and on the dynamometer (in vitro) provided the local leg curvature was taken into account. The stockings showed slightly different elastic properties (pressure amplitude difference upon leg movement 2–6mmHg). The interface pressure varied significantly when measured at different angular positions on the same circumference (range of change +40%; –20%). The differences were strongly correlated with the local radius (range of variation along the calf circumference 35–125 mm). The differences of local radii got smaller with higher interface pressures. Leg movements provoked simultaneous increases and decreases of interface pressure of up to 15 mmHg depending on the site of measurement. Leg circumference varied only slightly with movements pointing in either direction: 0.25 cm at the ankle (range +0.4; –0.4) and 0.33 cm at the calf (range +1.05; –1.45), respectively. The compressibility of the underlying tissue had no effect on the interface pressure. Conclusions: The interface pressure can be assessed reliably in vitro and in situ. It shows complex, quantitatively important non-uniform local variations both when measured along a given leg circumference at rest and when monitored at one particular site during movements. The changes reflect the discontinuity of the leg configuration and further alterations of the silhouette occurring with every muscle activation. Clearly, a massage effect of stockings is documented which does not necessarily reflect a global effect exerted on the leg.

Changes in Interface Pressure under Elastic and Short-Stretch Bandages during Posture Changes and Exercise

1998 ◽  
Vol 13 (1) ◽  
pp. 25-28 ◽  
Author(s):  
M. Hirai
Keyword(s):  
Clinical Practice ◽  
Prospective Study ◽  
Pressure Difference ◽  
Pressure Waveform ◽  
Pressure Measurements ◽  
Interface Pressure ◽  
Working Pressure ◽  
Time Of Application ◽  
College Of Nursing ◽  
Contraction And Relaxation

Objective: To evaluate the pressure under short-stretch and elastic bandages. Design: Prospective study in 20 healthy volunteers, comparing the two different kinds of bandages. Setting: Department of Surgery, Aichi Prefectural College of Nursing, Nagoya, Japan. Main outcome measures: Pressure measurements were made beneath the bandages with different initial pressures of 10, 20, 30, 40, 50, 60, and 70 mmHg, during supine resting, standing, tip-toe exercise and walking. Results: Short-stretch bandages showed a significant increase in pressure during standing and exercise at lower initial pressures compared with elastic bandages. In analysing the pressure waveform during tip-toe exercise and walking, a significantly greater pressure difference between muscle contraction and relaxation was noted for short-stretch bandages compared with elastic bandages at any initial pressures. Conclusions: Short-stretch bandages produce a higher working pressure and a larger pressure difference during exercise. However, the effect depends on the initial pressures at the time of application. In clinical practice, prevention of a decrease in pressure with time and uniform application of bandages are important.

Dependence of Blood Clot Lysis on the Mode of Transport of Urokinase into the Clot - A Magnetic Resonance Imaging Study in Vitro

1991 ◽  
Vol 65 (05) ◽  
pp. 549-552 ◽  
Author(s):  
A Blinc ◽  
G Planinšič ◽  
D Keber ◽  
O Jarh ◽  
G Lahajnar ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Pressure Difference ◽  
Volume Flow Rate ◽  
Blood Clot ◽  
Linear Regression Analysis ◽  
Imaging Study ◽  
Clot Lysis ◽  
Resonance Imaging

SummaryMagnetic resonance imaging was employed to study the dependence of clot lysing patterns on two different modes of transport of urokinase into whole blood clots. In one group of clots (nonperfused clots, n1 = 10), access of urokinase to the fibrin network was possible by diffusion only, whereas in the other group (perfused clots, n2 = 10) bulk flow of plasma containing urokinase was instituted through occlusive clots by a pressure difference of 3 .7 kPa (37 cm H2O) across 3 cm long clots with a diameter of 4 mm. It was determined separately that this pressure difference resulted in a volume flow rate of 5.05 ± 2.4 × 10−2 ml/min through occlusive clots. Perfused clots diminished in size significantly in comparison to nonperfused ones already after 20 min (p <0.005). Linear regression analysis of two-dimensional clot sizes measured by MRI showed that the rate of lysis was more than 50-times faster in the perfused group in comparison to the nonperfused group. It was concluded that penetration of the thrombolytic agent into clots by perfusion is much more effective than by diffusion. Our results might have some implications for understanding the differences in lysis of arterial and venous thrombi.

In Vitro Effect of Chlorquine and Picroliv on Plasmodium Berghei Induced Alterations in the Activity of Adenosine Triphosphatase, Aryl Hyrocarbon Hydroxylase Enzymes and Malondialdehyde in spleen Explant Culture

2020 ◽  
Vol 20 ◽  
Author(s):  
Anchal Trivedi ◽  
Aparna Misra ◽  
Esha Sarkar ◽  
Anil K. Balapure
Keyword(s):  
Drug Resistance ◽  
Plasmodium Berghei ◽  
Adenosine Triphosphatase ◽  
Explant Culture ◽  
Need To Evaluate ◽  
Mda Content ◽  
High Level ◽  
Vitro Effect ◽  
Positive Effect

Background: In recent years, great progress has been made in reducing the high level of malaria suffering worldwide. There is a great need to evaluate drug resistance reversers and consider new medicines against malaria. There are many approaches to the development of antimalarial drugs. Specific concerns must be taken in to account in these approaches, in particular there requirement for very in expensive and simple use of new therapies and the need to limit drug discovery expenses. Important ongoing efforts are the optimisation of treatment with available medications, including the use of combination therapy. The production of analogs of known agents and the identification of natural products, the use of compounds originally developed against other diseases, the assessment of overcoming drug resistance and the consideration of new therapeutic targets. Liver and spleen are the important organs which are directly associated with malarial complications. Aim: An analysis the Activity of Adenosine Triphosphatase, Aryl Hyrocarbon Hydroxylase Enzymes and Malondialdehyde in spleen Explant Culture. Objective: To determine in-Vitro Effect of Chlorquine and Picroliv on Plasmodium Berghei Induced Alterations in the Activity of Adenosine Triphosphatase, Aryl Hyrocarbon Hydroxylase Enzymes and Malondialdehyde in spleen Explant Culture. Material and method: 1-Histological preparation of spleen explants for paraplast embedding 2-Biochemicalstudies (Enzymes (Atpase, ALP&GST) and the level of protein, Malondialdehyde (MDA). Result: Splenomegalyis one of the three main diagnostic parameters of malaria infection besides fever and anaemia. Many enzymes present in the liver and spleen may also be altered or liberated under different pathological conditions. Enzymes (ATPase, ALP&GST) and the level of protein, Malondialdehyde (MDA) content was found to increase in the liver and spleen explants during malarial infection. In the liver and spleen derived from parasitized CQ treated animals, the activity of all the above enzymes (ATPase, ALP&GST) and the level of protein & MDA of liver/spleen reversed towards the normal for all the 4or3 days of incubations. Picroliv efficacy decreased with the increment of parasitaemia and at 60%parasitaemia. Conclusion: Alkalinephosphatase (ALP) was found to increase with increasing parasitaemia. After the addition of Picroliv to the medium, a decrement in the activity was observed up to day 4 of culture.A similar positive effect of Picroliv was observed on the ATPase and ALP activity of spleen explants.DNA and protein contents also increased in the parasitized liver cultured in the presence of picroliv.On the contrary, in the spleen explants DNA, protein and MDA content were found to decrease after Picroliv supplementation to the culture medium.

scholarly journals Mutations in fbiD (Rv2983) as a Novel Determinant of Resistance to Pretomanid and Delamanid in Mycobacterium tuberculosis

2020 ◽  
Vol 65 (1) ◽  
pp. e01948-20
Author(s):  
Dalin Rifat ◽  
Si-Yang Li ◽  
Thomas Ioerger ◽  
Keshav Shah ◽  
Jean-Philippe Lanoix ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Clinical Evidence ◽  
Clinical Samples ◽  
Loss Of Function ◽  
Wild Type ◽  
Content Type ◽  
Solid Media ◽  
High Level ◽  
Level Resistance

ABSTRACTThe nitroimidazole prodrugs delamanid and pretomanid comprise one of only two new antimicrobial classes approved to treat tuberculosis (TB) in 50 years. Prior in vitro studies suggest a relatively low barrier to nitroimidazole resistance in Mycobacterium tuberculosis, but clinical evidence is limited to date. We selected pretomanid-resistant M. tuberculosis mutants in two mouse models of TB using a range of pretomanid doses. The frequency of spontaneous resistance was approximately 10−5 CFU. Whole-genome sequencing of 161 resistant isolates from 47 mice revealed 99 unique mutations, of which 91% occurred in 1 of 5 genes previously associated with nitroimidazole activation and resistance, namely, fbiC (56%), fbiA (15%), ddn (12%), fgd (4%), and fbiB (4%). Nearly all mutations were unique to a single mouse and not previously identified. The remaining 9% of resistant mutants harbored mutations in Rv2983 (fbiD), a gene not previously associated with nitroimidazole resistance but recently shown to be a guanylyltransferase necessary for cofactor F420 synthesis. Most mutants exhibited high-level resistance to pretomanid and delamanid, although Rv2983 and fbiB mutants exhibited high-level pretomanid resistance but relatively small changes in delamanid susceptibility. Complementing an Rv2983 mutant with wild-type Rv2983 restored susceptibility to pretomanid and delamanid. By quantifying intracellular F420 and its precursor Fo in overexpressing and loss-of-function mutants, we provide further evidence that Rv2983 is necessary for F420 biosynthesis. Finally, Rv2983 mutants and other F420H2-deficient mutants displayed hypersusceptibility to some antibiotics and to concentrations of malachite green found in solid media used to isolate and propagate mycobacteria from clinical samples.

scholarly journals Allelic Exchange and Mutant Selection Demonstrate that Common Clinical embCAB Gene Mutations Only Modestly Increase Resistance to Ethambutol in Mycobacterium tuberculosis

2009 ◽  
Vol 54 (1) ◽  
pp. 103-108 ◽  
Author(s):  
Hassan Safi ◽  
Robert D. Fleischmann ◽  
Scott N. Peterson ◽  
Marcus B. Jones ◽  
Behnam Jarrahi ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
In Vitro Selection ◽  
Gene Mutations ◽  
Wild Type ◽  
Mutant Selection ◽  
Preferential Growth ◽  
Allelic Exchange ◽  
High Level ◽  
Isogenic Mutants

ABSTRACT Mutations within codon 306 of the Mycobacterium tuberculosis embB gene modestly increase ethambutol (EMB) MICs. To identify other causes of EMB resistance and to identify causes of high-level resistance, we generated EMB-resistant M. tuberculosis isolates in vitro and performed allelic exchange studies of embB codon 406 (embB406) and embB497 mutations. In vitro selection produced mutations already identified clinically in embB306, embB397, embB497, embB1024, and embC13, which result in EMB MICs of 8 or 14 μg/ml, 5 μg/ml, 12 μg/ml, 3 μg/ml, and 4 μg/ml, respectively, and mutations at embB320, embB324, and embB445, which have not been identified in clinical M. tuberculosis isolates and which result in EMB MICs of 8 μg/ml, 8 μg/ml, and 2 to 8 μg/ml, respectively. To definitively identify the effect of the common clinical embB497 and embB406 mutations on EMB susceptibility, we created a series of isogenic mutants, exchanging the wild-type embB497 CAG codon in EMB-susceptible M. tuberculosis strain 210 for the embB497 CGG codon and the wild-type embB406 GGC codon for either the embB406 GCC, embB406 TGC, embB406 TCC, or embB406 GAC codon. These new mutants showed 6-fold and 3- to 3.5-fold increases in the EMB MICs, respectively. In contrast to the embB306 mutants, the isogenic embB497 and embB406 mutants did not have preferential growth in the presence of isoniazid or rifampin (rifampicin) at their MICs. These results demonstrate that individual embCAB mutations confer low to moderate increases in EMB MICs. Discrepancies between the EMB MICs of laboratory mutants and clinical M. tuberculosis strains with identical mutations suggest that clinical EMB resistance is multigenic and that high-level EMB resistance requires mutations in currently unknown loci.

scholarly journals Aberrantly high activation of a FoxM1–STMN1 axis contributes to progression and tumorigenesis in FoxM1-driven cancers

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Jun Liu ◽  
Jipeng Li ◽  
Ke Wang ◽  
Haiming Liu ◽  
Jianyong Sun ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Poor Prognosis ◽  
Soft Agar ◽  
Transcriptional Level ◽  
Regulation Mechanism ◽  
Strong Positive Correlation ◽  
Cell Viability Assay ◽  
High Level

AbstractFork-head box protein M1 (FoxM1) is a transcriptional factor which plays critical roles in cancer development and progression. However, the general regulatory mechanism of FoxM1 is still limited. STMN1 is a microtubule-binding protein which can inhibit the assembly of microtubule dimer or promote depolymerization of microtubules. It was reported as a major responsive factor of paclitaxel resistance for clinical chemotherapy of tumor patients. But the function of abnormally high level of STMN1 and its regulation mechanism in cancer cells remain unclear. In this study, we used public database and tissue microarrays to analyze the expression pattern of FoxM1 and STMN1 and found a strong positive correlation between FoxM1 and STMN1 in multiple types of cancer. Lentivirus-mediated FoxM1/STMN1-knockdown cell lines were established to study the function of FoxM1/STMN1 by performing cell viability assay, plate clone formation assay, soft agar assay in vitro and xenograft mouse model in vivo. Our results showed that FoxM1 promotes cell proliferation by upregulating STMN1. Further ChIP assay showed that FoxM1 upregulates STMN1 in a transcriptional level. Prognostic analysis showed that a high level of FoxM1 and STMN1 is related to poor prognosis in solid tumors. Moreover, a high co-expression of FoxM1 and STMN1 has a more significant correlation with poor prognosis. Our findings suggest that a general FoxM1-STMN1 axis contributes to cell proliferation and tumorigenesis in hepatocellular carcinoma, gastric cancer and colorectal cancer. The combination of FoxM1 and STMN1 can be a more precise biomarker for prognostic prediction.

scholarly journals Goldmann Tonometry and Corneal Biomechanics

2021 ◽  
Vol 11 (9) ◽  
pp. 4025
Author(s):  
Dario Messenio ◽  
Marco Ferroni ◽  
Federica Boschetti
Keyword(s):  
Mechanical Properties ◽  
Anterior Chamber ◽  
Pressure Transducer ◽  
Pearson Correlation ◽  
Corneal Thickness ◽  
Applanation Tonometry ◽  
In Vitro Tests ◽  
Goldmann Tonometry ◽  
The Difference

Glaucoma is the second cause of irreversible blindness in the world. Intraocular pressure (IOP) is a recognized major risk factor for the development and progression of glaucomatous damage. Goldmann applanation tonometry (GAT) is internationally accepted as the gold standard for the measurement of IOP. The purpose of this study was to search for correlations between Goldmann tonometry and corneal mechanical properties and thickness by means of in vitro tests. IOP was measured by the Goldmann applanation tonometer (GIOP), and by a pressure transducer inserted in the anterior chamber of the eye (TIOP), at increasing pressure levels by addition of saline solution in the anterior chamber of enucleated pig eyes (n = 49). Mechanical properties were also determined by inflation tests. The GAT underestimated the real measurements made by the pressure transducer, with most common differences in the range 15–28 mmHg. The difference between the two instruments, highlighted by the Bland–Altman test, was confirmed by ANOVA, normality tests, and Mann–Whitney’s tests, both on the data arranged for infusions and for the data organized by pressure ranges. Pearson correlation tests revealed a negative correlation between (TIOP-GIOP) and both corneal stiffness and corneal thickness. In conclusion, data obtained showed a discrepancy between GIOP and TIOP more evident for softer and thinner corneas, that is very important for glaucoma detection.

scholarly journals Photodynamic Therapy Combined with Antibiotics or Antifungals against Microorganisms That Cause Skin and Soft Tissue Infections: A Planktonic and Biofilm Approach to Overcome Resistances

2021 ◽  
Vol 14 (7) ◽  
pp. 603
Author(s):  
Vanesa Pérez-Laguna ◽  
Isabel García-Luque ◽  
Sofía Ballesta ◽  
Antonio Rezusta ◽  
Yolanda Gilaberte
Keyword(s):  
Photodynamic Therapy ◽  
Soft Tissues ◽  
Combined Treatment ◽  
Resistance Pattern ◽  
Antimicrobial Photodynamic Therapy ◽  
Antimicrobial Drugs ◽  
Bacteria And Fungi ◽  
High Level ◽  
Selection Of

The present review covers combination approaches of antimicrobial photodynamic therapy (aPDT) plus antibiotics or antifungals to attack bacteria and fungi in vitro (both planktonic and biofilm forms) focused on those microorganisms that cause infections in skin and soft tissues. The combination can prevent failure in the fight against these microorganisms: antimicrobial drugs can increase the susceptibility of microorganisms to aPDT and prevent the possibility of regrowth of those that were not inactivated during the irradiation; meanwhile, aPDT is effective regardless of the resistance pattern of the strain and their use does not contribute to the selection of antimicrobial resistance. Additive or synergistic antimicrobial effects in vitro are evaluated and the best combinations are presented. The use of combined treatment of aPDT with antimicrobials could help overcome the difficulty of fighting high level of resistance microorganisms and, as it is a multi-target approach, it could make the selection of resistant microorganisms more difficult.

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