2018-06-25
Lithuanian scientists outfoxed drug resistant bacteria
The World Health Organisation (WHO) published a list of bacteria which reached critical levels of resistance and prevalence. The need to take action is considered at the highest political level: it is discussed on the G20 Health Ministers’ meetings, new R&D programmes are initiated and funded. Researchers from Vilnius Gediminas Technical University (VGTU) are also contributing to the priorities of WHO. The team represented by Dr. Vitalij Novickij is looking into new treatment methods.
As Dr. Vitalij Novickij explained to ELTA, wound infections caused by micro-organisms is one of the most common complications after surgeries and burns, or in the case of the immune system disorders. Such infections can be lethal. The situation becomes even more complicated with prevalence of micro-organisms which cause acute infections, and are resistant to bactericidal effect and most antibiotics.
For example, bacteria Pseudomonas aeruginosa is one of them. The bacteria take advantage of the immune system disorders. It attaches to our organism and causes infection. Often pharmacological treatment is ineffective, because the bacteria is able to penetrate the deeper tissues and form biofilms – a barrier which increases bacteria’s resistance to drugs up to tens of times.
That could lead to non-healing ulcers, the probability of blood infection increases significantly, and high morbidity rate due to ineffective drug treatment remains high, especially among patients with burns.
According to Dr. Vitalij Novickij, a senior researcher at VGTU, traditionally, representatives of biophysics and biology sciences are looking for solutions to this problem. Meanwhile, he as a representative of an interdisciplinary research field – bioelectronics – looked at this challenge from another perspective, i.e. technological.
A team of researchers lead by the ELTA’s interlocutor in cooperation with more than twelve laboratories in the State funded Research Institute Centre for Innovative Medicine, the Nature Research Centre, Vilnius University, Vytautas Magnus University, University of Edinburgh and University of Lublijana are developing a method of electroporation, which is based on the application of strong electric fields.
As Dr. Vitalij Novickij explained, strong pulsed electric fields can cause changes in cells’ membrane, and permeability to substances, for example drugs, increases; thus, drug effectiveness is higher and treatments are more successful.
The method of electroporation is widespread and is particularly noteworthy in cancer treatments. Until now, it was considered that it is not suitable for treatment of surface infections, because of the intensity of the electric field which is needed to inactivate bacteria. Harm caused to the skin and surrounding tissues would be much greater than the effect on the pathogen which caused the infection.
However, Dr. Vitalij Novickij together with partners managed to develop a new surface infection biocontrol method based on electroporation.
According to the researcher, the phenomena of electroporation directly depends on pulse systems – pulse generators and signals generated by them. The research team developed commercially unprecedented new pulse systems, electrodes and protocols, which enable them to effect only the surface – infected – layers of the skin tissue; thus, ensuring controlled, safe and effective treatment.
“The new method is based on application of nanosecond pulses of very high – MHz – frequency and high amplitude (>2-10 million V/m), which enable us to selectively destroy bacteria without injuring the deeper skin tissues. We can sterilise wounds this way, and control the effectiveness of medicinal substances, to which a microorganism had been resistant to before the electroporation,” said Dr. V. Novickij.
The effectiveness of the new method had been successfully tested and confirmed both in laboratories and in ethical animal tests using Pseudomonas aeruginosa and many other pathogens as model of infection.
The researcher expects that the next step is clinical trials of this antimicrobial therapy, but he did not say when this could happen or when this treatment will be available for patients.
According to Dr. Vitalij Novickij, the new method needs a few more years of an intensive work and further research. In addition, more funding is needed, and legal and bureaucratic hurdles have to be removed.
According to Vytautas Vaitkus, the Head of the Department of Thermal Injuries at the Republican Vilnius university hospital, the new method developed by the research team could help to increase the effectiveness of anti-inflammatory drugs when treating burn wounds.
“Our skin serves as a barrier for infection. Burn wounds are dangerous because a large area of surface is wounded, and bacteria can penetrate through deeper, necrotised tissues. Blood vessels are also injured in burns; thus, antibiotics are less effective because – taken orally or injected – they have to enter the bloodstream to kill bacteria,” the Head of the Department of Thermal Injuries explained to ELTA.
V. Vaitkus emphasised that for certain period of time antibiotics are not applied directly on wounds, the patients have to take it orally or receive intravenous injections. It is very hard for medicinal substances to reach wounds, and often burn wounds result in sepsis – a complication of an infection.
“People think that they do not have to contact a doctor if burn is small. It is not right. Even small burns can result in treatment in an intensive therapy unit because of sepsis. As drugs fighting the infection cannot overcome the necrotised tissue barrier,” said doctor.
As Dr. Vitalij Novickij explained to ELTA, wound infections caused by micro-organisms is one of the most common complications after surgeries and burns, or in the case of the immune system disorders. Such infections can be lethal. The situation becomes even more complicated with prevalence of micro-organisms which cause acute infections, and are resistant to bactericidal effect and most antibiotics.
For example, bacteria Pseudomonas aeruginosa is one of them. The bacteria take advantage of the immune system disorders. It attaches to our organism and causes infection. Often pharmacological treatment is ineffective, because the bacteria is able to penetrate the deeper tissues and form biofilms – a barrier which increases bacteria’s resistance to drugs up to tens of times.
That could lead to non-healing ulcers, the probability of blood infection increases significantly, and high morbidity rate due to ineffective drug treatment remains high, especially among patients with burns.
According to Dr. Vitalij Novickij, a senior researcher at VGTU, traditionally, representatives of biophysics and biology sciences are looking for solutions to this problem. Meanwhile, he as a representative of an interdisciplinary research field – bioelectronics – looked at this challenge from another perspective, i.e. technological.
A team of researchers lead by the ELTA’s interlocutor in cooperation with more than twelve laboratories in the State funded Research Institute Centre for Innovative Medicine, the Nature Research Centre, Vilnius University, Vytautas Magnus University, University of Edinburgh and University of Lublijana are developing a method of electroporation, which is based on the application of strong electric fields.
As Dr. Vitalij Novickij explained, strong pulsed electric fields can cause changes in cells’ membrane, and permeability to substances, for example drugs, increases; thus, drug effectiveness is higher and treatments are more successful.
The method of electroporation is widespread and is particularly noteworthy in cancer treatments. Until now, it was considered that it is not suitable for treatment of surface infections, because of the intensity of the electric field which is needed to inactivate bacteria. Harm caused to the skin and surrounding tissues would be much greater than the effect on the pathogen which caused the infection.
However, Dr. Vitalij Novickij together with partners managed to develop a new surface infection biocontrol method based on electroporation.
According to the researcher, the phenomena of electroporation directly depends on pulse systems – pulse generators and signals generated by them. The research team developed commercially unprecedented new pulse systems, electrodes and protocols, which enable them to effect only the surface – infected – layers of the skin tissue; thus, ensuring controlled, safe and effective treatment.
“The new method is based on application of nanosecond pulses of very high – MHz – frequency and high amplitude (>2-10 million V/m), which enable us to selectively destroy bacteria without injuring the deeper skin tissues. We can sterilise wounds this way, and control the effectiveness of medicinal substances, to which a microorganism had been resistant to before the electroporation,” said Dr. V. Novickij.
The effectiveness of the new method had been successfully tested and confirmed both in laboratories and in ethical animal tests using Pseudomonas aeruginosa and many other pathogens as model of infection.
The researcher expects that the next step is clinical trials of this antimicrobial therapy, but he did not say when this could happen or when this treatment will be available for patients.
According to Dr. Vitalij Novickij, the new method needs a few more years of an intensive work and further research. In addition, more funding is needed, and legal and bureaucratic hurdles have to be removed.
According to Vytautas Vaitkus, the Head of the Department of Thermal Injuries at the Republican Vilnius university hospital, the new method developed by the research team could help to increase the effectiveness of anti-inflammatory drugs when treating burn wounds.
“Our skin serves as a barrier for infection. Burn wounds are dangerous because a large area of surface is wounded, and bacteria can penetrate through deeper, necrotised tissues. Blood vessels are also injured in burns; thus, antibiotics are less effective because – taken orally or injected – they have to enter the bloodstream to kill bacteria,” the Head of the Department of Thermal Injuries explained to ELTA.
V. Vaitkus emphasised that for certain period of time antibiotics are not applied directly on wounds, the patients have to take it orally or receive intravenous injections. It is very hard for medicinal substances to reach wounds, and often burn wounds result in sepsis – a complication of an infection.
“People think that they do not have to contact a doctor if burn is small. It is not right. Even small burns can result in treatment in an intensive therapy unit because of sepsis. As drugs fighting the infection cannot overcome the necrotised tissue barrier,” said doctor.