Reducing Infections Using Nanotechnology

2014 ◽  
Vol 1621 ◽  
pp. 25-32
Author(s):  
Thomas J. Webster
Keyword(s):  
Computational Models ◽  
Air Flow ◽  
Cost Effective ◽  
Clinical Problem ◽  
High Morbidity ◽  
The Novel ◽  
Flow Conditions ◽  
Endotracheal Tubes ◽  
Surface Features ◽  
Log Reduction

ABSTRACTVentilator associated pneumonia (VAP) is a serious and costly clinical problem. Specifically, receiving mechanical ventilation for over 24 hours increases the risk of VAP and is associated with high morbidity, mortality and medical costs. Cost effective endotracheal tubes (ETTs) that are resistant to bacterial infection could help prevent this problem. The objective of this study was to determine differences in the growth ofStaphylococcus aureus(S. aureus) on nanomodified and unmodified polyvinyl chloride (PVC) ETTs under dynamic airway conditions. PVC ETTs were modified to have nanometer surface features by soaking them inRhizopus arrhisus,a fungal lipase. Twenty-four hour experiments (supported by computational models) showed that air flow conditions within the ETT influenced both the location and concentration of bacterial growth on the ETTs especially within areas of tube curvature. More importantly, experiments revealed a 1.5 log reduction in the total number ofS. aureuson the novel nanomodified ETTs compared to the conventional ETTs after 24 hours of air flow. This dynamic study showed that lipase etching can create nano-rough surface features on PVC ETTs that suppressS. aureusgrowth and, thus, may provide clinicians with an effective and inexpensive tool to combat VAP.

Nanomodified Endotracheal Tubes: Spatial Analysis of Reduced Bacterial Colonization in a Bench Top Airway Model

2012 ◽  
Vol 1418 ◽  
Author(s):  
Mary C. Machado ◽  
Keiko M. Tarquinio ◽  
Thomas J. Webster
Keyword(s):  
Computational Models ◽  
Bacterial Colonization ◽  
Air Flow ◽  
Cost Effective ◽  
Clinical Problem ◽  
High Morbidity ◽  
The Novel ◽  
Endotracheal Tubes ◽  
Surface Features ◽  
Log Reduction

ABSTRACTVentilator associated pneumonia (VAP) is a serious and costly clinical problem. Specifically, receiving mechanical ventilation for over 24 hours increases the risk of VAP and is associated with high morbidity, mortality and medical costs. Cost effective endotracheal tubes (ETTs) that are resistant to bacterial infection could help prevent this problem. The objective of this study was to determine differences in the growth ofStaphylococcus aureus(S. aureus) on nanomodified and unmodified polyvinyl chloride (PVC) ETTs under dynamic airway conditions. PVC ETTs were modified to have nanometer surface features by soaking them inRhizopus arrhisus,a fungal lipase. Twenty-four hour experiments (supported by computational models) showed that air flow conditions within the ETT influenced both the location and concentration of bacterial growth on the ETTs especially within areas of tube curvature. More importantly, experiments revealed a 1.5 log reduction in the total number ofS. aureuson the novel nanomodified ETTs compared to the conventional ETTs after 24 hours of air flow. This dynamic study showed that lipase etching can create nano-rough surface features on PVC ETTs that suppressS. aureusgrowth and, thus, may provide clinicians with an effective and inexpensive tool to combat VAP.

Bacterial Adhesion to Nanomodified Surfaces: Dynamic Flow Effects onS. aureusandP. aeruginosa

2013 ◽  
Vol 1498 ◽  
pp. 79-84
Author(s):  
Mary C. Machado ◽  
Keiko M. Tarquinio ◽  
Thomas J. Webster
Keyword(s):  
Bacterial Adhesion ◽  
Biofilm Formation ◽  
Cost Effective ◽  
Clinical Problem ◽  
Flow Chamber ◽  
High Morbidity ◽  
Pressure Gradients ◽  
Dynamic Flow ◽  
Endotracheal Tubes ◽  
Flow Effects

AbstractVentilator associated pneumonia (VAP) is a serious and costly clinical problem. Specifically, receiving mechanical ventilation over 24 hours increases the risk of VAP and is associated with high morbidity, mortality and medical costs. Cost effective endotracheal tubes (ETTs) that are resistant to bacterial infection would help to prevent this problem. The objective of this study was to determine differences in bacterial growth on nanomodified and unmodified ETTs under dynamic airway conditions. A bench top model based upon the general design of Hartmann et al. (1999) was constructed to test of the effectiveness of nanomodified ETTs under the airflow conditions present in the airway. Twenty-four hour studies performed in a dynamic flow chamber showed a marked difference in the biofilm formation on different areas of unmodified tubes. Areas where tubes were curved, such as at the entrance to the mouth and the connection between the oropharynx and the larynx, seemed to collect the largest amount of biofilm.The biofilm formation on ETTs in the airflow system after 24 hours showed a large difference depending upon where tubes were oriented within the apparatus. This illustrates the importance of dynamic flow on biofilm formation in pediatric ETTs. It is of particular interest that increased biofilm density on both unmodified and nanomodified tubes appeared to occur at curves in the tube where changes in flow pattern occurred. This emphasizes the need for more accurate models of airflow within pediatric ETTs, suggesting that not only does flow affect pressure gradients along the tube, but in fact, determines the composition of the film itself. More testing is needed to determine the effects of biofilm formation on the efficiency of ETT under airflow, however this study provides significant evidence for nanomodification alone (without the use of antibiotics) to decrease bacteria function.

Reduced Resistance to Air Flow from Nanomodified Endotracheal Tubes

2011 ◽  
Vol 1316 ◽  
Author(s):  
Mary C. Machado ◽  
Keiko M. Tarquinio ◽  
Thomas J. Webster
Keyword(s):  
Biofilm Formation ◽  
Cost Effective ◽  
Clinical Problem ◽  
Flow Chamber ◽  
High Morbidity ◽  
Ventilator Associated Pneumonia ◽  
Pressure Gradients ◽  
Dynamic Flow ◽  
Endotracheal Tubes ◽  
Significant Evidence

AbstractVentilator associated pneumonia (VAP) is a serious and costly clinical problem. Specifically, receiving mechanical ventilation over 24 hours increases the risk of VAP and is associated with high morbidity, mortality and medical costs. Cost effective endotracheal tubes (ETTs) that are resistant to bacterial infection would help to prevent this problem. The objective of this study was to determine differences in bacterial growth on nanomodified and unmodified ETTs under dynamic airway conditions, a bench top model based upon the general design of Hartmann et al. (1999) was constructed to test of the effectiveness of nanomodified ETTs under the airflow conditions present in the airway. Twenty-four hour studies performed in a dynamic flow chamber showed a marked difference in the biofilm formation on different areas of unmodified tubes. Areas where tubes were curved, such as at the entrance to the mouth and the connection between the oropharynx and the larynx, seemed to collect the largest amount of biofilm. On the nanomodified tubes biofilm formation was markedly different occurring on smaller pieces.The biofilm formation on ETTs in the airflow system after 24 hours showed a large difference depending upon where tubes were oriented within the apparatus. This illustrates the importance of dynamic flow on biofilm formation in pediatric ETTs. It is of particular interest that increased biofilm density on both unmodified and nanomodified tubes appeared to occur at curves in the tube where changes in flow pattern occured. This emphasizes the need for more accurate models of airflow within pediatric ETTs, suggesting that not only does flow affect pressure gradients along the tube, but in fact, determines the composition of the film itself. More testing is needed to determine the effects of biofilm formation on the efficiency of ETT under airflow, however this study provides significant evidence for nanomodification alone (without the use of antibiotics) to decrease bacteria function.

Malignant Pleural Effusion: Still a Long Way to Go

2019 ◽  
Vol 14 (1) ◽  
pp. 24-30 ◽  
Author(s):  
Fausto Meriggi
Keyword(s):  
Pleural Effusion ◽  
Malignant Pleural Effusion ◽  
English Language ◽  
Metastatic Cancer ◽  
Primary Tumour ◽  
Clinical Problem ◽  
Therapeutic Options ◽  
High Morbidity ◽  
Sclerosing Agents ◽  
Pubmed Database

Background:Malignant pleural effusion, which is a common clinical problem in patients with cancer, may be due to both primary thoracic tumours or to a metastatic spread in the chest and constitutes the first sign of disease in approximately 10% of patients. Almost all cancers can potentially produce a pleural effusion. The presence of malignant tumour cells in the pleural fluid is generally indicative of advanced disease and is associated with high morbidity and mortality with reduced therapeutic options. Dyspnoea during mild physical activity or at rest is generally the typical sign of restrictive respiratory failure. </P><P> Methods: This is a systematic review of all the main articles in the English language on the topic of malignant pleural effusion and reported by the Pubmed database from 1959 to 2018. I reviewed the literature and guidelines with the aims to focus on what is known and on future pathways to follow the diagnosis and treatment of malignant pleural effusions.Results:The main goal of palliation of a malignant pleural effusion is a quick improvement in dyspnoea, while thoracentesis under ultrasound guidance is the treatment of choice for patients with a limited life expectancy or who are not candidates for more invasive procedures such as drainage using an indwelling small pleural catheter, chemical pleurodesis with sclerosing agents, pleurectomy or pleuro-peritoneal shunt.Conclusion:Despite progress in therapeutic options, the prognosis remains severe, and the average survival is 4-9 months from the diagnosis of malignant pleural effusion. Moreover, mortality is higher for patients with malignant pleural effusion compared with those with metastatic cancer but no malignant pleural effusion. Therefore, the prognosis of these patients primarily depends on the underlying disease and the extension of a primary tumour. This review focuses on the most relevant updates in the management of malignant pleural effusion.

scholarly journals Modeling and optimization of radish root extract drying as peroxidase source using spouted bed dryer

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Shahrbanoo Hamedi ◽  
M. Mehdi Afsahi ◽  
Ali Riahi-Madvar ◽  
Ali Mohebbi
Keyword(s):  
Kinetic Parameters ◽  
Flow Rate ◽  
Air Flow ◽  
Cost Effective ◽  
Industrial Applications ◽  
Interactive Effects ◽  
Root Extract ◽  
Air Flow Rate ◽  
Spouted Bed ◽  
Radish Root

AbstractThe main advantages of the dried enzymes are the lower cost of storage and longer time of preservation for industrial applications. In this study, the spouted bed dryer was utilized for drying the garden radish (Raphanus sativus L.) root extract as a cost-effective source of the peroxidase enzyme. The response surface methodology (RSM) was used to evaluate the individual and interactive effects of main parameters (the inlet air temperature (T) and the ratio of air flow rate to the minimum spouting air flow rate (Q)) on the residual enzyme activity (REA). The maximum REA of 38.7% was obtained at T = 50 °C and Q = 1.4. To investigate the drying effect on the catalytic activity, the optimum reaction conditions (pH and temperature), as well as kinetic parameters, were investigated for the fresh and dried enzyme extracts (FEE and DEE). The obtained results showed that the optimum pH of DEE was decreased by 12.3% compared to FEE, while the optimum temperature of DEE compared to FEE increased by a factor of 85.7%. Moreover, kinetic parameters, thermal-stability, and shelf life of the enzyme were considerably improved after drying by the spouted bed. Overall, the results confirmed that a spouted bed reactor can be used as a promising method for drying heat-sensitive materials such as peroxidase enzyme.

Experimental Investigation on the Heat Transfer of a Portable Forced-Convection Solar Air Heater

2010 ◽  
Author(s):  
Mohammad Fakoor Pakdaman ◽  
Pejman Zohorian Izadi ◽  
Mohammad Javadinia Azari ◽  
Amir Lashkari
Keyword(s):  
Forced Convection ◽  
Air Flow ◽  
Bottom Plate ◽  
Solar Air Heater ◽  
Air Flow Rate ◽  
Flow Conditions ◽  
Maximum Enhancement ◽  
Air Heater ◽  
Weather Changes ◽  
Plate Absorber

A cross-corrugated portable forced-convection solar air heater has been designed, fabricated, and developed. A wavelike bottom plate has been positioned crosswise to the air flow while rectangular baffles have been attached to the flat-plate absorber. The relative corrugation height, (e/Dh) ranges between 0.24 and 0.4, and relative baffles distance (l/L) varies between 0.21 and 0.48. The air flow rate in the heater duct has been varied in the range of 0.001 kgs−1 to 0.01kgs−1 (Reynolds number ranges from 350 to 3500), while other thermal specifications such as inlet, outlet, and plate temperatures have varied due to weather changes. Results of this study have been compared with those related to smooth ducts and other literatures, and the maximum enhancement in Nusselt number is observed to be approximately five times of that of the smooth duct under similar flow conditions. Finally, thermal efficiency of the device for different case studies has been determined and compared with other researches.

scholarly journals Outcome of Acute Peritoneal Dialysis in Northern Tanzania

2012 ◽  
Vol 32 (3) ◽  
pp. 261-266 ◽  
Author(s):  
Kajiru Gad Kilonzo ◽  
Sudakshina Ghosh ◽  
Siya Anaeli Temu ◽  
Venance Maro ◽  
John Callegari ◽  
...  
Keyword(s):  
Peritoneal Dialysis ◽  
Patient Outcomes ◽  
Kidney Injury ◽  
Cost Effective ◽  
High Morbidity ◽  
Poor Countries ◽  
Resource Limited ◽  
Northern Tanzania ◽  
Nephrology Care ◽  
Technical Simplicity

Data on the burden of acute kidney injury (AKI) in resource-poor countries such as Tanzania are minimal because of a lack of nephrology services and an inability to recognize and diagnose AKI with any certainty. In the few published studies, high morbidity and mortality are reported. Improved nephrology care and dialysis may lower the mortality from AKI in these settings. Hemodialysis is expensive and technically challenging in resource-limited settings. The technical simplicity of peritoneal dialysis and the potential to reduce costs if consumables can be made locally, present an opportunity to establish cost-effective programs for managing AKI. Here, we document patient outcomes in a pilot peritoneal dialysis program established in 2009 at a referral hospital in Northern Tanzania.

Numerical analysis of non-aligned inputs M-type micromixers with different shaped obstacles for biomedical applications

2021 ◽  
pp. 095440892110516
Author(s):  
Muhammad Irfan ◽  
Imran Shah ◽  
Usama M Niazi ◽  
Muhsin Ali ◽  
Sadaqat Ali ◽  
...  
Keyword(s):  
Structural Design ◽  
Biomedical Applications ◽  
Structural Changes ◽  
Nanoparticle Synthesis ◽  
Fluid Mixing ◽  
The Novel ◽  
Flow Conditions ◽  
Mixing Index ◽  
Mixing Performance ◽  
Passive Micromixer

Fluid mixing in lab-on-a-chip devices at laminar flow conditions result in a low mixing index. The reason is dominant diffusion over the convection process. The mixing index can be improved by certain changes in the micromixer structural design like introducing obstacles in the path of fluid flow. These obstacles will make dominant the advection process over the diffusion process. The main contribution of this work is based on proposing the novel hybrid type micromixer design for enhancing the mixing quality. Three non-aligned M-type and non-aligned M-type with obstacles passive type micromixers are analyzed by COMSOL5.5. These designs are hybrid types because different structural changes are combined in a single design for mixing improvement. First of all the straight non-aligned inlets, M-type passive micromixer (SMTM) is analyzed. It is observed that mixing performance is improved because of M-shaped mixing units and non-aligned inlets. This improvement is deemed to be not enough so different shaped obstacles are introduced in the micromixer design. These designs based on obstacles are named horizontal rectangular M-type micromixer, square M-type micromixer, and vertical rectangular M-type micromixer. The mixing index for SMTM, square M-type micromixer, horizontal rectangular M-type micromixer, and vertical rectangular M-type micromixer at Reynolds number Re = 60 is respectively given by 71.1%, 83.21%, 84.45%, and 89.99%. The mixing index of vertical rectangular M-type micromixer was 59.34% − 87.65% for Re = 0.5–100. Vertical rectangular M-type micromixer is concluded with the better-mixing capability design among the proposed ones. Based on these simulation results, the vertical rectangular M-type micromixer design can be utilized for mixing purposes in biomedical applications like nanoparticle synthesis and biomedical sample preparation for drug delivery.

scholarly journals A New Fluorescence Probe for Rapid Detection of Amyloid

2018 ◽  
Author(s):  
Nidhi Gour ◽  
Vivek Shinh Kshtriya ◽  
Bharti Koshti ◽  
Shradhey Gupta ◽  
khashti Ballabh Joshi ◽  
...  
Keyword(s):  
Rapid Detection ◽  
Control Experiment ◽  
Fluorescence Probe ◽  
Photophysical Properties ◽  
Cost Effective ◽  
The Novel ◽  
High Quantum Yield ◽  
Turn On ◽  
Heat Treated ◽  
Amyloidogenic Peptides

<p>We report efficient synthesis and photophysical properties of a novel fluorescent pyridothiazole based construct by a facile methodology and its application as a sensor for rapid, selective as well as sensitive detection of amyloid fibres. The novel compound has exceptionally high quantum yield and sensitivity. The fluorescence of pyridothiazole construct is completely quenched (Turn-OFF) upon addition of cupric ions and the fluorescence is recovered on addition of amyloidogenic peptides like A<i>β</i><sub>42 </sub>(Turn-ON). The control experiment with native and heat treated BSA suggest that the new probe binds to beeta/<i>β</i> sheets present in amyloid. The new probe offers direct visualization of fluorescence ‘Turn-OFF’ ‘Turn-ON’ under long UV without the use of sophisticated instrumentation. Hence, a very simple, facile and cost-effective methodology for the rapid detection of amyloid is presented and it may in all possibility pave the way for the design of a better probe for sensing amyloids than conventional ThT.</p>

scholarly journals Formulation, Stability, Pharmacokinetic, and Modeling Studies for Tests of Synergistic Combinations of Orally Available Approved Drugs Against Ebola Virus In Vivo

2021 ◽  
Author(s):  
Courtney L. Finch ◽  
Julie Dyall ◽  
Shuang Xu ◽  
Elizabeth A. Nelson ◽  
Elena Postnikova ◽  
...  
Keyword(s):  
Mouse Model ◽  
Oral Delivery ◽  
Ebola Virus ◽  
Cost Effective ◽  
High Morbidity ◽  
Strong Activity ◽  
Approved Drugs ◽  
Formulation Stability ◽  
Synergistic Combinations

Outbreaks of Ebola ebolavirus (EBOV) have been associated with high morbidity and mortality. Milestones have been reached recently in the management of EBOV disease (EVD) with licensure of an EBOV vaccine and two monoclonal antibody therapies. However, neither vaccines nor therapies are available for other disease-causing filoviruses. In preparation for such outbreaks, and for more facile and cost-effective management of EVD, we seek a cocktail containing orally available and room temperature stable drugs with strong activity against multiple filoviruses. We previously showed that (bepridil + sertraline) and (sertraline + toremifene) synergistically suppress EBOV in cell cultures. Here we describe steps towards testing these combinations in a mouse model of EVD. We identified a vehicle suitable for oral delivery of the component drugs and determined that, thus formulated the drugs are equally active against EBOV as preparations in DMSO, and they maintain activity upon storage in solution for up to seven days. Pharmacokinetic (PK) studies indicated that the drugs in the oral delivery vehicle are well tolerated in mice at the highest doses tested. Collectively the data support advancement of these combinations to tests for synergy in a mouse model of EVD. Moreover, mathematical modeling based on human oral PK projects that the combinations would be more active in humans than their component single drugs.

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