• 제목/요약/키워드: Photogem

검색결과 11건 처리시간 0.029초

Photodynamic Therapy for Methicillin-resistant Staphylococcus aureus with High-level Mupirocin Resistance using 630 nm Light-emitting Diode

  • Kwon, Pil-Seung;Kim, Jin-Kyung
    • 대한의생명과학회지
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    • 제16권4호
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    • pp.331-339
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    • 2010
  • This study aims to evaluate the effect of Photodynamic Therapy (PDT) against methicillin-resistant Staphylococcus aureus with high-level mupirocin resistance (Hi-Mup MRSA). To examine the antimicrobial effect of photogem-mediated PDT against Hi-Mup MRSA, CFU quantifications, bacteria cell viability tests, and disk diffusion antimicrobial susceptibility tests were evaluated. In addition, one of PDT mechanisms was investigated by accumulating photogem ($10\;{\mu}g/ml$) in Hi-Mup MRSA. Photogem-mediated PDT properly inhibited the colony formation of Hi-Mup MRSA. Viable bacteria decreased greatly after a PDT application with photogem $10\;{\mu}g/ml$ at energy density $15\;J/cm^2$. The diameter of the inhibition zone around susceptible disks increased after PDT. In addition, we confirmed the accumulation of photogem in bacteria through fluorescent images. These results demonstrated that excellent photosensitization of Hi-Mup MRSA can be achieved using photogem with 630 nm LED irradiation. Thus, PDT may make survival Hi-Mup MRSA inactive.

The Effects of Photodynamic Therapy for Vancomycin-resistant Enterococci

  • Kwon, Pil Seung
    • 대한임상검사과학회지
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    • 제43권3호
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    • pp.124-132
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    • 2011
  • The aim of this study was to evaluate the effects of the photosensitizer photogem with light-emitting diode (LED) on vancomycin-resistant enterococci (VRE). Two VRE strains isolated from the feces of patients. that was identificated Enterococcus faecium (vanA) and Enterococcus gallinarum (vanC1) using traditional biochemical tests and confirmed VRE genotyping from using polymerase chain reaction. In addition, three strains were used Enterococcus. faecalis CDC-286 (vanA), E. faecalis CDC-583 (vanB) and E. gallinarum CDC-42 (vanC1). To examine the antimicrobial effect of photogem mediated photodynamic therapy (PDT) against, CFU quantification and Disk diffusion antimicrobial susceptibility test were evaluated. The effects of Photodynamic therapy was not associated with genotype. Photogem mediated PDT perfectly inhibited the colony formation of E. faecalis CDC-286. The number of viable bacteria decreased greatly after PDT application with photogem $50{\mu}g/mL$ and energy density of $15J/cm^2$. The diameter of inhibition zone was increased to after PDT more than before PDT. The case of vancomycin disc on E. faecalis CDC-583 and E. galinanum-Patient were changed from resistant to intermediate resistant, from intermediate resistant to susceptable. These results demonstrate that lethal photosensitization of VRE can be achieved using photogem plus 630 nm LED irradiation.

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Antibacterial Effect of Photodynamic Therapy using Photogem and a 632 nm Diode Laser on $Helicobacter$ $pylori$

  • Ahn, Jin-Chul;Shin, Jang-In;Chang, So-Young;Kim, Hong-Ja;Hong, Seong-No
    • 대한의생명과학회지
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    • 제17권4호
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    • pp.363-366
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    • 2011
  • Eradication of $H.$ $pylori$, usually carried out by using antimicrobial agents, is essential for preventing gastric ulcers and cancers. The $H.$ $pylori$ isolates, however, have continuously grown antimicrobial resistance, which have caused difficulty in treating the bacteria and in turn, photodynamic therapy (PDT) has been found to be effective in inducing deaths of variety of bacteria. After PDT treatment, the number of colony forming units (CFU), the morphologic changes, and flow cytometry were observed. In the PDT group containing 100 and 200 ${\mu}g$/ml photogem, no live $H.$ $pylori$ was observed, while 10 and 50 ${\mu}g$/ml photogem were only partially effective. $H.$ $pylori$ of the PDT group also displayed distortion and shrinkage in morphology. This study demonstrated that photogem-mediated PDT effectively induces deaths of $H.$ $pylori$.

Photodynamic Therapy for Methicillin-resistant Staphylococcus aureus Strain using Photogem and 630 nm LED

  • 안진철
    • 대한의생명과학회지
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    • 제14권4호
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    • pp.269-274
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    • 2008
  • Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most common nosocomial pathogens. It is associated with hospitals is now being isolated in the community. The aim of this study was to evaluate the antibacterial effect of photodynamic therapy using Photogem and 630 nm LED on MRSA and methicillin-sensitive Staphylococcus aureus (MSSA). The broth cultured MRSA and MSSA incubated with various concentrations of Photogem (500,50,5 and $0.5{\mu}g/mL$) for 4 h. Then 630 nm LED was given at $9\;J/cm^2$, $20{\mu}l$ of the exposed bacteria solution was inoculated onto agar plate. Plates were incubated for 24 hand colonies were counted. The PDT group was effective in killing MRSA and MSSA at the Photogem dose of $50{\mu}g/mL$. But MSSA is more sensitive than MRSA in photodynamic effect. Other groups (light only, sensitizer only, or no treatment) observed no bacterial cell killing. These results raise the possibility of using PDT with or without antimicrobial drugs to eradicate MRSA and MSSA. In order to confirm this result, we need to further study bacterial death mechanism and in vivo study.

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Moraxella catarrhalis의 광역학적 비활성화 (Photodynamic Inactivation of Moraxella catarrhalis)

  • 홍성노;권필승;김대식
    • 대한임상검사과학회지
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    • 제39권1호
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    • pp.19-24
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    • 2007
  • The aim of this study was to evaluate the bacterial effects of Moraxella catarrhalis in otitis media with effusion (OME) by photodynamic therapy (PDT). Bacterial suspensions (10000 CFU/mL) were prepared. The colony forming units (CFU) of Moraxella catarrhalis have been measured after an application of photogem plus 632 nm diode laser irradiation. One ml of the bacterial suspensions have been incubated in the dark for 3h with various concentrations of photogem ($0.625{\sim}5.0_{\mu}g/mL$) and then irradiated with 632 nm diode laser ($15J/cm^2$). After, the PDT Moraxella catarrhalis suspensions ($50{\mu}L$) were inoculated on chocolate agar plate and cultured in the dark at $37^{\circ}C$, 5% $CO_2$ condition for 18h. The colony forming units off the bacteria were measured. Also transmission electron microscopy (TEM) was employed to evaluate the effect of otitis media pathogens by PDT. The nucleus of Moraxella catarrhalis was stained using green fluorescent nucleic acid dye thiazole orange and the fluorescence intensity of the nucleus was measured by flow cytometry. The PDT was effective in killing Moraxella catarrhalis at the photogem dose of $5.0_{\mu}g/mL$, respectively, As assessed by flow cytometry analysis the fluorescence intensity of the nucleus got lower after PDT. TEM result appeared to able to cause damage to the bacterial membranes. On the basis of these findings, bacterial photodynamic therapy with photogem can be considered to be a promising new therapeutic approach for OME.

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Photodynamic Therapy for Methicillin-resistant Staphylococcus aureus Using Various Photosensitizer

  • ;조윤경
    • 대한의생명과학회지
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    • 제15권3호
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    • pp.233-239
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    • 2009
  • The aim of this study was to evaluate the photodynamic effect of various photosensitizing agents against methicillin-resistant Staphylococcus aureus (MRSA). MRSA was exposed to light from a 632 urn diode laser (15 J/$cm^2$) in the presence of various photosensitizer, such as photofrin, photogem, radachlorine and ALA. In vivo study was performed using ICR mice. Twenty eight mice had a standard wound ($100\;mm^2$) created on the dorsum, and MRSA was inoculated into the wound region. The four groups were classified as follows: (1) the untreated control group (bacteria alone), (2) the bacteria plus light group (15 J/$cm^2$), (3) the bacteria plus photofrin group (kept in the dark), and (4) the photodynamic therapy (PDT) group (bacteria, photofrin, and light). After photofrin (dose 1 mg/kg) injection, the experimental group was irradiated with 632 urn diode laser (15 J/$cm^2$) for 30 minutes after In vitro results of PDT showed the complete killing of MRSA at the photofrin, radachlorine, and photogem However, ALA-PDT was ineffective on MRSA viability. In vivo results showed that photofrin has therapeutic effect on the wound infection. These results demonstrate that selective lethal photosensitization of MRSA can be achieved using phofrin, photogem and radachlorin. Thus, PDT can inactivate MRSA survival.

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폐암에서 광역동치료술의 효과 (Effect of Photodynamic Therapy in Lung Cancer)

  • 윤성호;한경택;김경남;이승일
    • Tuberculosis and Respiratory Diseases
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    • 제57권4호
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    • pp.358-363
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    • 2004
  • 연구배경 : 폐암에서 광역동치료는 미세침습성 비소세포폐암 및 기관지폐쇄를 일으키는 악성종양에 대한 기관지내 치료를 미국식품의약국(FDA)에서 승인한 상태이다. 국내에서는 폐암세포주에 대한 보고 외에 폐암에 대한 광역동치료 연구가 많지 않아 임상 성적에 대한 보고가 없어 이에 저자들은 폐암에서 시행된 광역동치료에 대한 결과를 문헌고찰과 함께 보고하고자 한다. 방 법 : 2002년 8월부터 2003년 5월까지 조선대학교 병원에서 기관지 내시경을 통해 조직학적으로 진단된 폐암환자 중 10명을 대상으로 하여 광역동치료 48시간 전에 광과민제(Photogem$^{(R)}$, Lomonosov institute of Fine Chemical, Russia)를 2.0mg/Kg을 정맥 주사한 후 48시간, 72시간에 Diode LASER system(Biolitec Inc., Germany, wavelength; 633nm)을 사용하여 광역 동치료를 시행하였다. 결 과 : 10명 중 9예에서 부분관해와 함께 기관지 개통을 보였으며, 1예에서는 변화를 보이지 않았다. 결 론 : 저자들은 광역동치료를 통해 기관지폐쇄로 인한 호흡곤란 및 기관지 폐쇄와 관련된 폐렴이 개선됨을 확인 하였으며, 합병증이 적어 안전한 기관지내 치료법으로 생각된다. 앞으로 광역동 치료에 대한 장기적인 결과 및 적절한 치료 적응증 및 조기 폐암에서 치료효과 등에 대한 연구가 필요할 것으로 생각된다.

Photodynamic Therapy-Mediated Temporal Expression of Thymidine Kinase Genes Ligated to the Human Heat Shock Promotor: Preliminary in vitro Model Study of Enhanced Phototoxicity by PDT-Induced Gene Therapy

  • Kim, Mo-Sun;Kim, Tae-An;Kim, Jong-Ki
    • Journal of Photoscience
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    • 제9권3호
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    • pp.41-43
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    • 2002
  • PDT-mediated cyototoxicity basically depends on the penetrated light-dose into the tumor tissue. This limits the efficiency of PDT to the superficial tumor region typically less than 1 cm. The localized photochemical generation of reactive oxygen species, including singlet oxygen is known to increase expression of assortment of early response genes including heat shock protein. In order to increase PDT cytotoxicity in the treatment of solid tumor, it is desirable to combine PDT with other therapeutic effects. In this preliminary study we evaluated enhanced cytotoxicity from the PDT-mediated expression of thymidine kinase in a transfected tumor cell line. Two types of photo sensitizers, a hematoporphyrin derivative(Photogem, Russia) and aluminium sulphonated phthalocyanine(Photosense, Russia) were used to evaluate the overexpression of hsp-70 in PDT-treated cell. Transient increase of hsp-70 was observed at 6-8 hrs later following irradiation in the photosense-treated cell whereas it was not observed in Photogem-treated cell. In the presence of ganciclovia, transfected cell showed a 17% increase in the cytotoxicity compared to the PDT only cell.

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The Biologic Effect of Millimeter Wave Irradiation Followed to Photodynamic Therapy on the Tumor

  • Ahn, Jin-Chul;Lee, Chang-Sook;Chang, So-Young;Yoon, Sung-Chul
    • 대한의생명과학회지
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    • 제17권1호
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    • pp.79-84
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    • 2011
  • Photodynamic therapy consists of a photosensitizer, suitable light source and oxygen. The excitation of the photosensitizer at a cancer mass results in oxidation which would ultimately reduce the mass via apoptosis. Millimeter wave (MMW) therapy has also been known to be effective on cancer cell mass reduction, human cell regeneration and immunity enhancement among the Russian clinicians and scientists. In the present study, the two modalities were combined to achieve synergistic effects while reducing the administration dosage of the photosensitizer, photogem, thus minimizing the side effects. The CT-26 adenocarcinoma cell mass was implanted on mice and the tumors were exposed to a simple MMW irradiation or a combined treatment of MMW and PDT. The treatments continued for 4 weeks and the size of the tumor was measured continuously. The significant therapeutic result of MMW was not found during 4 weeks, preferably more cancer recurrence possibility after MMW irradiation was observed. The results of this study suggest that the combination of MMW irradiation and photodynamic treatment should not be recommended. The result of the MMW treatment alone, however, displayed suppressive effect on cancer cell proliferation for both in vitro and in vivo. The results of the present study suggest that the millimeter wave therapy deserves a further study.