Effect of hemX gene deletion on heme synthesis in Bacillus amyloliquefaciens / 生物工程学报

Heme, which exists widely in living organisms, is a porphyrin compound with a variety of physiological functions. Bacillus amyloliquefaciens is an important industrial strain with the characteristics of easy cultivation and strong ability for expression and secretion of proteins. In order to screen the optimal starting strain for heme synthesis, the laboratory preserved strains were screened with and without addition of 5-aminolevulinic acid (ALA). There was no significant difference in the heme production of strains BA, BAΔ6 and BAΔ6ΔsigF. However, upon addition of ALA, the heme titer and specific heme production of strain BAΔ6ΔsigF were the highest, reaching 200.77 μmol/L and 615.70 μmol/(L·g DCW), respectively. Subsequently, the hemX gene (encoding the cytochrome assembly protein HemX) of strain BAΔ6ΔsigF was knocked out to explore its role in heme synthesis. It was found that the fermentation broth of the knockout strain turned red, while the growth was not significantly affected. The highest ALA concentration in flask fermentation reached 82.13 mg/L at 12 h, which was slightly higher than that of the control 75.11 mg/L. When ALA was not added, the heme titer and specific heme production were 1.99 times and 1.45 times that of the control, respectively. After adding ALA, the heme titer and specific heme production were 2.08 times and 1.72 times higher than that of the control, respectively. Real-time quantitative fluorescent PCR showed that the expressions of hemA, hemL, hemB, hemC, hemD, and hemQ genes at transcription level were up-regulated. We demonstrated that deletion of hemX gene can improve the production of heme, which may facilitate future development of heme-producing strain.

Eficacia clínica de la terapia fotodinámica por 5-ALA tópico en el manejo onco-preventivo de lesiones de leucoplasia oral. Una revisión sistemática / Clinical efficacy of topical 5-ALA photodynamic therapy in the onco-preventive management of oral leukoplakia lesions. A systematic review

Objetivo: La leucoplasia oral es el desorden maligno de la mucosa bucal más prevalente a nivel global y su manejo clínico sigue siendo un desafío. Se llevó a cabo una revisión sistemática para determinar la eficacia clínica de la terapia fotodinámica mediada por ácido 5-aminolevulínico tópico como una alternativa de quimio-prevención para las diferen- tes formas clínicas de la leucoplasia oral. Materiales y métodos: Empleando términos MeSH, se realizó una búsqueda exhaustiva en diferentes bases digi- tales de ensayos clínicos publicados en inglés en los últimos 30 años acerca del uso de la terapia fotodinámica mediada por ácido 5-aminolevulínico tópico como fotosensibilizador, y radiación láser de baja intensidad o luz LED como posibles fuentes de iluminación. Resultados: La revisión sistematizada que aplicó la guía PRISMA mostró una eficacia del 88,6% para este modo de fototerapia en el manejo de leucoplasias orales, con un 60,7% de respuesta completa y 27,9% de respuesta parcial. Además, el tamaño de efecto fue mayor para las formas clíni- cas homogéneas con cambios displásicos, independientemen- te del tipo de fuente de luz. La ausencia de respuesta fue del 11,4%, pero la evidencia empleada en este análisis fue mo- derada. Conclusión: La terapia fotodinámica mediada por áci- do 5-aminolevulínico tópico parece ser una alternativa útil en el manejo onco-preventivo de lesiones de leucoplasia oral. Sin embargo, es recomendable ejecutar ensayos clínicos controla- dos y aleatorizados con metodologías homogéneas que per- mitan generar un meta-análisis con un alto nivel de evidencia

Aim: Oral leukoplakia is globally the most prevalent ma- lignant disorder of the oral mucosa and its clinical manage- ment remains a challenge. A systematic review was carried out to determine the clinical efficacy of photodynamic therapy mediated by topical 5-aminolevulinic acid as an alternative for chemoprevention in the different clinical forms of oral leu- koplakia. Materials and methods: Using MeSH terms, an ex- haustive search was carried out in different digital databases of clinical trials published in English in the last 30 years on the use of photodynamic therapy mediated by topical 5-ami- nolevulinic acid as a photosensitizer, and low-intensity laser radiation or LED light as possible lighting sources. Results: The systematized review using PRISMA guide- lines showed an efficacy of 88.6% for this mode of photother- apy in the management of oral leukoplakias, based on 60.7% of complete response and 27.9% of partial response. In addi- tion, the effect size was larger in homogeneous clinical forms with dysplastic changes, regardless of the type of light source. There was an 11.4% of absence of response, but the evidence used in this analysis was moderate. Conclusion: Photodynamic therapy mediated by topical 5-aminolevulinic acid seems to be a useful alternative in the onco-preventive management of oral leukoplakia lesions. However, it is recommendable to perform controlled and ran- domized clinical trials with homogeneous methodologies that allow the generation of a meta-analysis with a high level of evidence (AU)

Extending the Indications of 5-Aminolevulinic Acid for Fluorescence-Guided Surgery for Different Central Nervous System Tumors: A Series of 255 Cases in Latin America

Introduction Fluorescence guidance with 5-aminolevulinic acid (5-ALA) is a safe and reliable tool in total gross resection of intracranial tumors, especially malignant gliomas and cases of metastasis. In the present retrospective study, we have analyzed 5-ALA-induced fluorescence findings in different central nervous system (CNS) lesions to expand the indications of its use in differential diagnoses. Objectives To describe the indications and results of 5-ALA fluorescence in a series of 255 cases. Methods In 255 consecutive cases, we recorded age, gender, intraoperative 5-ALA fluorescence tumor response, and 5-ALA postresection status, as well the complications related to the method. Postresection was classified as '5-ALA free' or '5-ALA residual'. The diagnosis of histopathological tumor was established according to the current classification of the World Health Organization (WHO). Results There were 195 (76.4%) 5-ALA positive cases, 124 (63.5%) of whom underwent the '5-ALA free' resection. The findings in the positive cases were: 135 gliomas of all grades; 19 meningiomas; 4 hemangioblastomas; 1 solitary fibrous tumor; 27 metastases; 2 diffuse large B cell lymphomas; 2 cases of radionecrosis; 1 inflammatory disease; 2 cases of gliosis; 1 cysticercosis; and 1 immunoglobulin G4-related disease.

Avaliação da redução da carga viral do papilomavírus humano por meio da captura híbrida após terapia fotodinâmica em lesões intraepiteliais cervicais alto grau / Load reduction assessment human papillomavirus viral through hybrid capture after photodynamic therapy in injuries high grade cervical intraepithelial

Contexto e objetivo: No mundo, aproximadamente 20 milhões de mulheres encontram-se infectadas pelo papilomavírus humano (HPV). Esta infecção pode ser assintomática ou causar papilomas verrucosos benignos, neoplasias intraepiteliais cervicais (NICs) de baixo ou alto grau, carcinoma cervical, vaginal e anal. Os tratamentos atuais para as NICs ainda são muito invasivos e destrutivos. Sendo assim, existe a necessidade do desenvolvimento de modalidades menos agressivas. A terapia fotodinâmica (TFD) atende a esses pedidos, induzindo a morte seletiva de células infectadas pelo vírus. Este artigo tem o objetivo de analisar a redução da carga viral de HPV em pacientes com lesões intraepiteliais cervicais de alto grau (LIEAG) antes e após a TFD. Métodos: Foram incluídas 28 pacientes portadoras de NICs de alto grau que realizaram tratamento com 2,5 g de creme contendo o pró-fármaco ácido 5-metil aminolevulínico (MAL) a 20%, por aproximadamente 10 horas, com posterior aplicação da luz de LED com comprimento de onda de 630 nm e irradiância de 120 mW/cm2, por 25 minutos, entregando uma dose total de 180 J/cm2, em duas sessões. As pacientes foram avaliadas por meio de captura híbrida antes e após a TFD. Resultados: Após análise criteriosa, observou-se redução significativa da carga viral dos HPVs de alta oncogenicidade após a TFD (P = 0,0334) nas pacientes com LIEAG. O mesmo não foi observado em relação aos HPVs de baixo grau oncogênico (P = 0,4038). Conclusão: A TFD parece ser eficaz e promissora na diminuição da carga viral em pacientes com LIEAG induzidos por subtipos de HPV de alto grau oncogênico.

Engineering the C4 pathway of Corynebacterium glutamicum for efficient production of 5-aminolevulinic acid / 生物工程学报

5-aminolevulinic acid (5-ALA) plays an important role in the fields of medicine and agriculture. 5-ALA can be produced by engineered Escherichia coli and Corynebacterium glutamicum. We systematically engineered the C4 metabolic pathway of C. glutamicum to further improve its ability to produce 5-ALA. Firstly, the hemA gene encoding 5-ALA synthase (ALAS) from Rhodobacter capsulatus and Rhodopseudomonas palustris were heterologously expressed in C. glutamicum, respectively. The RphemA gene of R. palustris which showed relatively high enzyme activity was selected. Screening of the optimal ribosome binding site sequence RBS5 significantly increased the activity of RphemA. The ALAS activity of the recombinant strain reached (221.87±3.10) U/mg and 5-ALA production increased by 14.3%. Subsequently, knocking out genes encoding α-ketoglutarate dehydrogenase inhibitor protein (odhI) and succinate dehydrogenase (sdhA) increased the flux of succinyl CoA towards the production of 5-ALA. Moreover, inhibiting the expression of hemB by means of sRNA reduced the degradation of 5-ALA, while overexpressing the cysteine/O-acetylserine transporter eamA increased the output efficiency of intracellular 5-ALA. Shake flask fermentation using the engineered strain C. glutamicum 13032/∆odhI/∆sdhA-sRNAhemB- RBS5RphemA-eamA resulted in a yield of 11.90 g/L, which was 57% higher than that of the original strain. Fed-batch fermentation using the engineered strain in a 5 L fermenter produced 25.05 g/L of 5-ALA within 48 h, which is the highest reported-to-date yield of 5-ALA from glucose.

5-aminolevulinic Acid and Surgical Margin Analysis in Calvarial Metastasis with Pericranium or Dural Extension: Technical Note

Metastasis to the calvarium with direct pericranium or dural infiltration may be treated with radical surgical removal in selected cases. We describe microsurgical resection of calvarial metastases with fluorescence-guided technique using 5-aminolevulinic acid (5-ALA) in two female patients with breast cancer. Fluorescence findings were positive in both cases. Margins in the scalp and dural layer were 5-ALA negative at the end of surgical removal. Intraoperative pathology was performed in all cases to confirm if oncological limits were free of disease. One case was 5-ALA positive in the outer layer of the dura-mater and another in the pericranium. At the end of the removal in both cases, the surgicalmargins were 5-ALA fluorescence-free. Intraoperative pathology confirmed oncological limits of the resection. 5-aminolevulinic acid fluorescence-guided surgery for calvarial metastases with pericranium and/or dural extension seems to be a safe and reliable method to aid the surgical margins for complete removal, possibly delaying or avoiding adjuvant irradiation for progression control.

5-Aminolevulinic acid photoactivated over planktonic and biofilm forms of Enterococcus faecalis as a pharmacological therapy alternative

The purpose of the study was to evaluate the antibacterial effect of protoporphyrin IX (PpIX) generated by the exogenous administration of 5-aminolevulinic acid or δ-ALA and activated with an argon laser over a planktonic and biofilm of Enterococcus faecalis (E. faecalis) as a pharmacological therapy alternative. A planktonic strain of E. faecalis was cultured with a solution of ∂-ALA (40 µg/mL)-thioglycolate solution for 13 min, and a biofilm of E. faecalis was cultured in a δ-ALA (80 µg/mL)-thioglycolate solution for 13 min. Then, both were irradiated with an argon laser. Finally, the antibacterial effect was evaluated by counting the CFU in planktonic form, and a LIVE/DEAD viability cell test. The production and accumulation of PpIX from exogenously administered δ-ALA on E. faecalis in planktonic and biofilm forms was confirmed by spectrofluorometry. The irradiation of PpIX with an argon laser produced an antibacterial effect on E. faecalis in planktonic and biofilm form, even without biofilm disruption, at a concentration of 40 µg/mL and 80 µg/mL of δ-ALA, respectively. The exogenous administration of δ-ALA in combination with laser irradiation on planktonic and biofilm forms of E. faecalis produces an effective antibacterial effect as complement or alternative to pharmacological therapies

Effect of 5-aminolevulinic Acid Photodynamics Therapy on Biofilm of / 中国医学科学院学报

To investigate the effect of 5-aminolevulinic acid photodynamic therapy (ALA-PDT) on () biofilm. biofilms were constructed on a cell slide and treated with ALA-PDT.According to different light doses,the biofilms were divided into six groups:ALA-PDT group [ALA-PDT1 (50 J/cm),ALA-PDT2 group (100 J/cm),ALA-PDT3 group (200 J/cm)],ALA-only group (ALA group),light-only group (LED),and a negative control group (ALA-PDT-group).The biofilm structure and the ratio of the dead bacteria/live bacteria were observed using a laser confocal microscope (CLSM).Biofilm viability was measured using the XTT assay. CLSM showed that the biofilm structures of ALA group and LED group were not significantly different from that of ALA-PDT-group,whereas the biofilm structure was more seriously damaged in ALA-PDT1 group,ALA-PDT2 group,and ALA-PDT3 group than in the ALA-PDT-group.The ratios of the dead/live bacteria in ALA-PDT-group,ALA group,LED group,ALA-PDT1 group,ALA-PDT2 group,and ALA-PDT3 group were 0.350±0.033, 0.305±0.046, 0.330±0.032, 1.525±0.439, 2.293±0.148 and 3.092±0.189,respectively.ALA group(=0.003, =1.000)and LED group(=-0.025, =1.000)did not significantly differ from the ALA-PDT-group.However,the ratio of dead/live bacteria in ALA-PDT-group was significantly lower than those in ALA-PDT1 group (=-0.162, <0.001),ALA-PDT2 group (=-0.254, <0.001),and ALA-PDT3 group (=-0.352, <0.001).The values of the XTT assay were were 0.462±0.028,0.465±0.044,0.437±0.047,0.301±0.040,0.207±0.001,and 0.110±0.007,respectively,in ALA-PDT-group,ALA group,LED group,ALA-PDT1 group,ALA-PDT2 group,and ALA-PDT3 group.Although the values of XTT assay in ALA(=-0.044, =1.000)and LED groups (=-0.020, =1.000)did not significantly differ from that in ALA-PDT-group,it was significantly higher in ALA-PDT-group than in ALA-PDT1 group (=1.175, <0.001),ALA-PDT2 group (=1.942, <0.001),and ALA-PDT3 group (=-0.352, =2.742, <0.001). ALA-PDT has an inhibitory effect on biofilm.ALA-PDT destroys biofilm structure and inhibits biofilm viability.

Photodynamic therapy guidelines for the management of oral leucoplakia / 国际口腔科学杂志·英文版

With recent developments in photosensitizers and light delivery systems, topical 5-aminolevulinic acid-mediated photodynamic therapy (ALA-PDT) has become the fourth alternative therapeutic approach in the management of oral leucoplakia (OLK) due to its minimally invasive nature, efficacy, and low risk of systemic side effects and disfigurement. This report presents step-by-step guidelines for applying topical ALA-PDT in the management of OLK based on both the clinical experience of the authors and a systematic review of the current literature. Studies using protocols with standardized parameters and randomized clinical trials at multiple centres with adequate sample sizes and both interim and long-term follow-ups are needed before universally applicable guidelines can be produced in this field.

Fluorescence Guided Surgery with 5-Aminolevulinic Acid for Resection of Spinal Cord Ependymomas

STUDY DESIGN: A retrospective study. PURPOSE: We report our experience with 5-aminolevulinic acid (5-ALA)–assisted resection of spinal cord ependymomas in adults. OVERVIEW OF LITERATURE: Ependymoma is the most frequent primary spinal cord tumor in adults. Surgery is the treatment of choice in most cases. However, while complete resection is achieved in approximately 80% of cases, clinical improvement is achieved in 15% only. Five-ALA fluorescence–guided surgery seems to be useful for this tumor type. METHODS: We studied 14 patients undergoing 5-ALA fluorescence-guided surgery for spinal cord ependymomas in our service. The modified McCormick classification was used to determine clinical status and the degree of resection was assessed with magnetic resonance imaging. RESULTS: Of the 14 patients, the tumor showed an intense emission of fluorescence in 12 and the fluorescence was weak and nonuniform in two. Complete resection was achieved in 11 cases. According to the McCormick classification, 10 patients improved, two remained the same, and two deteriorated. CONCLUSIONS: Our results confirm that 5-ALA fluorescence-guided resection is useful in spinal cord ependymoma resection. Although the rate of complete resections is similar to that in published series without 5-ALA, clinical results are better when using 5-ALA with a lower percentage of clinical deterioration.

Indications of 5-Aminolevulinic Acid and Intraoperative MRI in Glioma Surgery: First Cases in Latin America in a Single Reference Center

Introduction The improvement on the extent of resection (EOR) of gliomas with the combination of 5-aminolevulinic acid (5-ALA) and intraoperative magnetic resonance imaging (iMRI) has been demonstrated in previous studies. We present our results with the combined use of 5-ALA and (iMRI) in the surgery of glial lesions. Methods A total of 64 cases of patients with intracranial gliomas who underwent image-guided surgery using 5-ALA with and without (iMRI) were reviewed. All patients underwent an early postoperative MRI to evaluate the EOR. Other intra-operative techniques (awake surgery, electrophysiological stimulation and monitoring) were also performed according to the location of the tumor. Results A total of 18 tumors did not show intraoperative 5-ALA fluorescence (according to the World Health Organization [WHO] classification of tumors, 2 WHO-grade I, 14 WHOgrade II, 1 WHO-grade III and 1 WHO-grade IV), and 46 tumors showed intraoperative 5-ALA fluorescence (3 WHO-grade II, 3 WHO-grade III, 40 WHO-grade IV). In 28 of the 46 5-ALA positive cases, a safe 5-ALA free resection was achieved. In the 5-ALA negative cases, the (iMRI) findings guided the EOR, and complete resection was achieved in 11 cases. Complete resection was opted out in gliomas infiltrating eloquent areas. Conclusions The combined use of 5-ALA and IMRI showed improved results in glioma surgery, offering the safest maximal EOR. In the 5-ALA positive cases (mostly highgrade), fluorescence was a more useful tool. In the 5- ALA negative cases (mostly lowgrade), the (iMRI) was decisive to guide the EOR of the tumor.

Introdução Em estudos anteriores, foi demonstrado um aperfeiçoamento na extensão da resecção (EDR) de gliomas com a combinação de ácido 5-aminolevulínico (5-ALA) e a imagem de ressonância magnética intraoperatória (iRM). Nossos resultados são apresentados com o uso combinado de 5-ALA e (iRM) para a cirurgia de lesões gliais. Métodos Foram revisados 64 casos de gliomas intracranianos submetidos a cirurgia guiada por imagem por meio do uso de 5-ALA, com ou sem RMI. Todos os pacientes foram submetidos a ressonância magnética (RM) pré-operatória para a avaliação da EDR do tumor. Outras técnicas intraoperatórias (cirurgia acordado, estimulação eletrofisiológica e monitoração) também foram realizadas segundo a localização do tumor. Resultados Um total de 18 tumores não apresentaram fluorescência com o 5-ALA (segundo a classificação de tumores da Organização Mundial de Saúde [OMS], 2 com grau OMS I, 14 com grau II, 1 com grau III e 1 com grau IV) e 46 tumores foram fluorescentes (3 com grau II, 3 com grau III, 40 com grau IV). Dos 46 casos positivos para 5-ALA, em 28 foi obtida uma ressecção segura e livre. Nos casos negativos para 5-ALA, os achados da (iRM) orientaram a EDR, e alcançou-se ressecção total em 11 casos. A ressecção total foi descartada em gliomas com infiltração em áreas eloquentes. Conclusões O uso combinado de 5-ALA e (iRM) mostrou melhores resultados na cirurgia de gliomas, oferecendo uma EDR de segurança máxima. Nos casos positivos para 5-ALA (a maioria de grau alto), a fluorescência mostrou-se um instrumento mais útil. Nos casos negativos para 5-ALA (a maioria de grau baixo), a RMI foi decisiva para orientar a EDR tumoral.

A new optical intra-tissue fiber irradiation ALA-PDT in the treatment of acne vulgaris in rabbit model: improved safety and tolerability

Abstract Background: Photodynamic therapy with topical aminolevulinic acid (ALA-PDT) has been suggested to be effective in treatment of acne vulgaris. However, adverse events occur during and after treatment. Objectives: To compare the efficacy and tolerability of optical intra-tissue fiber irradiation (OFI) ALA-PDT versus traditional ALA-PDT in treatment of acne vulgaris in rabbit models. Methods: Twenty-five rabbits of clean grade were used. Twenty rabbits were randomly selected to establish acne model and the other five were used as control. Rabbits in model group (40 ears) were further divided into four groups (10 ears/group): I, OFI-ALA-PDT with the head of optical fiber inserted into the target lesion (intra-tissue); II, traditional ALA-PDT group; III, OFI group; IV, blank control group without any treatment. Uncomfortable symptoms, adverse events, and effectiveness rates were recorded on post-treatment day 14, 30, and 45. Results: On post-treatment day 14, the effectiveness rate in OFI-ALA-PDT group was obviously higher than that of the other three groups (P<0.05). However, no improved effects were observed in OFI-ALA-PDT group on day 30 and 45. During the period of treatment, the frequencies of uncomfortable symptoms in ALA-PDT group were obviously higher than those in the other three groups (P<0.05). The adverse event rate in OFI-ALA-PDT group was obviously lower than that of the ALA-PDT group (P<0.05) Study limitations: The unblindness of the study and temporary animal models of acne induced may hamper the assessment and monitoring of the results, and future studies are still needed to clarify it further. Conclusion: The OFI-ALA-PDT group (intra-tissue irradiation) showed no improved efficacy on treating rabbit ear acne but had higher safety and better tolerability.

Daylight photodynamic therapy - Experience and safety in treatment of actinic keratoses of the face and scalp in low latitude and high brightness region

ABSTRACT Daylight photodynamic therapy has been used in countries with high latitudes during the summer for actinic keratoses treatment with reports of similar efficacy to conventional photodynamic therapy. We evaluate its safety in 20 patients in the city of Fortaleza, a local with low latitude and high brightness. Sixteen patients did not report any discomfort due to the procedure. Daylight photodynamic therapy is an easy application method with great tolerability by the patient and has the possibility of being performed throughout the year in these regions. It can mean a promising tool in the control of skin cancer.

Photodynamic therapy - a non-invasive treatment modality for precancerous lesions

Introduction: Oral premalignant lesions are conditions having high potential tendency for transformation into malignancy. The use of a conservative and effective treatment modality is one of the best strategies for cancer prevention. Photodynamic therapy [PDT] is a non-invasive method for topical and selective treatment of oral precancerous lesions. The present study was taken up to determine the efficacy of PDT in oral precancerous lesions

Methods: The study consisted 13 patients with 24 oral leukoplakia [OL] lesions and 8 with 20 oral lichen planus [OLP] lesions, divided into control and study groups. These lesions were affecting various intraoral sites, the buccal mucosa being the most common site followed by tongue and gingiva. The treatment regimen of PDT included 98% 5-aminolevulinic acid [5-ALA] which is topical applied and irradiated with light emitting diode [LED] of 420 nm wavelengths at several sessions

Results: In OL 16.6% of cases showed complete response, 66.6% partial response and 16.6% no response of the lesions to the treatment. In OLP 80% and 20% of the lesions showed partial and no response respectively. The differences with control groups for OL + OLP were found to be significant [P<0.001]

Conclusion: Based on the results of the present study, we can conclude that PDT appears to be a feasible alternative to conventional therapy for oral premalignant lesions

In-vitro study of photodynamic therapy of antibiotic-resistant staphylococcus from patients with chronic rhinosinusitis / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To evaluate the photodynamic therapy (PDT) against multi-antibiotic-resistant Staphylococcus aureus (S. aureus) and Staphylococcus epidermidis (S.epidermidis) obtained from patients with chronic rhinosinusitis (CRS).</p><p><b>METHODS</b>Forty-five CRS patients who had been given medical treatment but still needed endoscopic surgery were included in this study. The mucus from middle meatus was collected from these patients during surgery, followed by separation of S. aureus and S. epidermidis and drug sensitive test. The strains which could form biofilm were selected. Light emitting diode (LED) array with a major wavelength of (633±10) nm was used as light source and 5-Aminolevulinic acid (ALA) was used as photosensitizer in this PDT experiment. The safe range of LED dose and ALA concentration which were not toxic to bacteria by themselves were confirmed, and then did PDT experiment on S. aureus and S. epidermidis. The data of bacterial colony forming unit were transformed to lgCFU before statistical analysis.The Graph Pad Prism 5 software was used to analyzed the data.</p><p><b>RESULTS</b>Thirteen S. aureus and 16 S. epidermidis were included in this experiment(from 45 patients), all of them were multi-antibiotic-resistant bacteria, and four of S. aureus and five of S. epidermidis could form biofilm in each group. In planktonic S. aureus experiment, the mean lgCFU was 8.32±0.31 in control group whereas the experiment group was 6.47±0.67 (t=9.01, P<0.01), and in planktonic S. epidermidis experiment the final data was 8.34±0.20 (control group) and 6.97±0.59 (experiment group) (t=8.84, P<0.01). In biofilm S. aureus experiment, the mean lgCFU was 8.68±0.05 (control group), 6.90±0.96(experiment group) (t=3.68, P<0.05); and in biofilm S. epidermidis experiment the data was 8.67±0.05 (control group), 7.29±0.61 (experiment group, t=5.07, P<0.01).</p><p><b>CONCLUSION</b>Our results demonstrated that ALA-mediated PDT on multi-antibiotic-resistant S. aureus and S. epidermidis from CRS patients was effective in vitro. Additional work defining if the PDT treatment would damage the nasal mucosa and further checking the effectiveness of PDT in vivo is still needed.</p>

Long-term recurrence of nonmelanoma skin cancer after topical methylaminolevulinate photodynamic therapy in a dermato-oncology department

Abstract: BACKGROUND: Most available studies on the efficacy of topical photodynamic therapy focus on short-to medium-term results. Long-term data are scarce. OBJECTIVE: To evaluate the long-term efficacy of photodynamic therapy with topical methylaminolevulinate to treat Bowen's disease and basal cell carcinoma in the clinical practice setting of a dermato-oncology department. METHODS: The study included patients diagnosed with Bowen's disease or basal cell carcinoma, and who received photodynamic therapy from 2004 to 2008. Treatment protocol and clinical follow-up were standardized. The primary endpoint was clinically observed recurrence in a previous photodynamic therapy-treated area. Descriptive and survival analyses were performed. RESULTS: A total of 31 Bowen's disease lesions and 44 superficial basal cell carcinoma were treated, with a median follow-up of 43.5 months. Recurrence was observed in 14 Bowen's disease lesions (53.8%) and in 11 superficial basal cell carcinoma (33.3%). Significantly higher estimates for recurrence rates were found in patients with Bowen's disease (p=0.0036) or those aged under 58 years (p=0.039). The risk of recurrence was higher in patients with Bowen's disease than in those with superficial basal cell carcinoma and younger patients. CONCLUSIONS: Recurrence should be considered when choosing to treat non-melanoma skin cancer with photodynamic therapy. Younger age and Bowen's disease were independent predictors for long-term recurrence, suggesting the need to establish an extended period of follow-up for this subset of patients.