1.In-vitro determination of minimum inhibitory concentration (MIC) and contact time of povidone-iodine against Staphylococcus aureus and Klebsiella aerogenes using micro suspension test, colorimetric resazurin microplate assay, and Dey Engley neutralizer assay
Azita Racquel G. Lacuna ; Micaella C. Dato ; Loisse Mikaela M. Loterio ; Geraldine B. Dayrit ; Sharon Yvette Angelina M. Villanueva ; Maria Margarita M. Lota
Acta Medica Philippina 2025;59(4):113-124
BACKGROUND AND OBJECTIVE
The human nasal passages host major human pathogens. Recent research suggests that the microbial communities inhabiting the epithelial surfaces of the nasal passages play a key factor in maintaining a healthy microenvironment by affecting both resistance to pathogens and immunological responses. Colonization of the nasal cavity by different pathogens such as Staphylococcus aureus and Klebsiella aerogenes, is associated with a higher postoperative infection morbidity. Povidone-iodine (PVP-I) as an antiseptic has been proven to display high antibacterial, antiviral, and antifungal properties even at low concentrations, and was shown to be effective in the control of infections to limit their impact and spread. It can be used as a topical antiseptic for skin decontamination and wound management, as a nasal spray, or as a gargle. There are different methods in testing the efficacy of potential antimicrobial suspensions. This study aimed to determine the concentration of PVP-I that is most effective in nasal decolonization using microsuspension test and colorimetric minimum inhibitory concentration (MIC) determination assays, resazurin microtiter assay (REMA), and Dey-Engley (D/E) neutralizer assay. The findings of this study will contribute to knowledge regarding the intended use of PVP-I in microbial control, particularly in bacterial infections.
METHODSSeveral dilutions (2.0%, 1.0%, 0.5%, 0.25%, 0.1% and 0.09%) of commercially bought 10% (10 mg per 100 ml) povidone-iodine were prepared and tested against a standardized inoculum (1x105) of Staphylococcus aureus and Klebsiella aerogenes at different contacttimes (5 seconds, 10 seconds, 30 seconds, 1 minute, and 5 minutes). Microdilution suspension test was performed to determine the log reduction per variable, while REMA and D/E neutralizer assay were used to determine the MIC. A value of greater than or equal to 5 log reduction was considered effective for microdilution suspension test. Estimates of agreement statistics were used to interpret the results of the assay in which the overall percent agreement (OPA), positive percent agreement (PPA), negative percent agreement (NPA), and Cohen’s kappa statistics were calculated.
RESULTSPovidone-iodine concentration of 0.25% exhibited ?5 log reduction against K. aerogenes at the minimum contact time of 5 seconds. On the other hand, a slightly higher PVP-I concentration was required to achieve ?5 log reduction for S. aureus at 0.5% concentration and a minimum contact time of 1 minute. There was an observed concordance of the results of REMA and D/E neutralizer as MIC colorimetric indicators, which yielded an overall test percent agreement of 90.30% (95% CI: 84.73–94.36), and a strong level of agreement (? = 0.8, pCONCLUSION
Low povidone-iodine concentrations (i.e., 0.5% against S. aureus and 0.25% against K. aerogenes) were observed to have bactericidal activity of at least 5 log reduction as rapid as the minimum contact time of 5 seconds. Furthermore, D/E and REMA, as colorimetric indicators, had comparable performance (OPA = 90.30%; ? = 0.8, p
Human
;
Bacteria
;
Povidone-iodine
;
Microbial Sensitivity Tests
;
Anti-infective Agents, Local
;
Enterobacter Aerogenes
;
Staphylococcus Aureus
2.Identification and expression analysis of TCP family members in tobacco (Nicotiana tabacum L.).
Shize WANG ; Yun LI ; Yucui HAN ; Shizhou YU ; Shuang WANG ; Yong LIU ; Xiaohu LIN
Chinese Journal of Biotechnology 2024;40(1):226-238
TCP family as plant specific transcription factor, plays an important role in different aspects of plant development. In order to screen TCP family members in tobacco, the homologous sequences of tobacco and Arabidopsis TCP family were identified by genome-wide homologous alignment. The physicochemical properties, phylogenetic relationships and cis-acting elements were analyzed by bioinformatics. The homologous genes of AtTCP3/AtTCP4 were screened, and RT-qPCR was used to detect the changes of gene expression upon 20% PEG6000 treatment. The results show that tobacco contains 63 TCP family members. Their amino acid sequence length ranged from 89 aa to 596 aa, and their protein hydropathicity grand average of hydropathicity (GRAVY) ranged from -1.147 to 0.125. The isoelectric point (pI) ranges from 4.42 to 9.94, the number of introns is 0 to 3, and the subcellular location is all located in the nucleus. The results of conserved domain and phylogenetic relationship analysis showed that the tobacco TCP family can be divided into PCF, CIN and CYC/TB1 subfamilies, and each subfamily has a stable sequence. The results of cis-acting elements in gene promoter region showed that TCP family genes contain low docile acting elements (LTR) and a variety of stress and metabolic regulation related elements (MYB, MYC). Analysis of gene expression patterns showed that AtTCP3/AtTCP4 homologous genes (NtTCP6, NtTCP28, NtTCP30, NtTCP33, NtTCP42, NtTCP57, NtTCP63) accounted for 20% PEG6000 treatment significantly up-regulated/down-regulated expression, and NtTCP30 and NtTCP57 genes were selected as candidate genes in response to drought. The results of this study analyzed the TCP family in the tobacco genome and provided candidate genes for the study of drought-resistance gene function and variety breeding in tobacco.
Nicotiana/genetics*
;
Phylogeny
;
Plant Breeding
;
Amino Acid Sequence
;
Arabidopsis
;
Polyethylene Glycols
3.Olmsted syndrome in a 12-year-old Filipino male: A case report and future directions.
Aznaida T. Pandapatan ; Cindy J. Tan ; Joyce Anne S. Tan
Acta Medica Philippina 2024;58(17):83-87
We report a case of a Filipino child who presented with yellowish hyperkeratotic plaques on the palms and soles with palmar transgredient extension to the wrists, a yellowish hyperkeratotic plaque over the coccygeal area, and brownish-black hyperkeratotic perianal plaques. Patient had delayed physical development and short stature, but no intellectual disability. Histopathologic examination showed palmoplantar keratoderma. These clinical findings of symmetrical palmoplantar keratoderma with periorificial keratotic plaques were consistent with Olmsted Syndrome. Oral retinoids with topical keratolytics afforded significant improvement with increased hand mobility. Although there is no curative management for these patients, current experimental therapies like epidermal growth factor receptor (EGFR) inhibitors and Transient Receptor Potential Vanilloid-3 (TRPV3) antagonists are promising. Olmsted Syndrome is a rare genodermatosis with 73 cases officially reported as of this writing. This is the first case to be reported from the Philippines.
Human ; Male ; Child: 6-12 Yrs Old ; Keratoderma, Palmoplantar ; Acitretin
4.A case of systematized epidermal nevus (Nevus Unius Lateris) in a 20-year-old Filipino female treated with ablative CO2 laser and topical tretinoin
Maria Emilia Ruth V. Eusebio ; Emy Christine C. Onishi-Limchoa ; Doha Mae Laurisse M. Manalo-Legas
Acta Medica Philippina 2024;58(17):88-93
This is a case of a 20-year-old female with no known comorbidities presenting with verrucous plaques arranged in a unilateral blaschkoid distribution at birth. Biopsy was consistent with epidermal nevus hence patient was diagnosed as systematized epidermal nevus, Nevus Unius Lateris type. Gold standard treatment is full thickness surgical excision however, due to the extensive involvement, treatment of this condition remains a challenge. Hence, non-surgical combination of ablative CO2 laser and topical tretinoin 0.1% were done. Thinner lesions (1-3 mm) showed lower recurrence (50%) as compared to thicker lesions (>3 mm) showing 100% recurrence after six months. Hence, another CO2 laser session is needed. Quality of life was measured using the Dermatologic Life Quality Index (DLQI) with noted 35% improvement post-treatment.
CO2 laser
;
lasers, gas
;
tretinoin
;
retinoids
5.Isotretinoin-induced gouty arthritis in a 26-year-old Filipino female patient with acne vulgaris: A case report
Charlene Lorraine A. Elio ; Ma. Dulce Amor Vivian F. Galang
Journal of the Philippine Dermatological Society 2024;33(Suppl 1):1-1
INTRODUCTION
Oral isothretinoin is the treatment of choice in moderate to severe acne vulgaris. The most common adverse effect is mild mucocutaneous symptoms and the most seious risk is related to teratogenecity. Hyperuricemia and gouty arthritis are rarely associated with isotretinoin therapy.
CASE REPORTWe report a case of a 26-year-old female patient with no known comorbidities who was started on isotretinoin therapy for acne vulgaris. The patient presented with baseline hyperuricemia with no joint pains or swelling. Two and a half weeks later after initiation of isotretinoin therapy, the patient developed pain and swelling on the left wrist, hence was started on urate-lowering medications and maintained on isotretinoin tharapy. The patient had no recurrence of joint pains and remains symptom-free for six months later.
Human ; Female ; Adult: 25-44 Yrs Old ; Acne Vulgaris ; Arthritis, Gouty ; Hyperuricemia ; Isotretinoin ; Retinoids
6.A tale of scales: Siblings with lamellar ichthyosis treated with acitretin
Patricia Anne Nicole O. Ramirez-ecarma ; Jerlyn Maureen P. Sevas ; Alexis Paula D. Ibañ ; es ; Patricia Ysabel G. Oreta-arboleda ; Ma. Angela M. Lavadia ; Lily Lyralin L. Tumalad
Journal of the Philippine Medical Association 2024;103(1):94-104
INTRODUCTION
Lamellar ichthyosis (LI) is an inherited rare disorder characterized by generalized scaling presenting at birth and persisting throughout life. It presents at birth with a collodion membrane, later developing into large, brown scales across the skin. LI requires ongoing treatment and monitoring due to physical and psychosocial impacts. This study highlights siblings who showed substantial quality-of-life improvements with oral retinoid therapy.
OBJECTIVETo present and discuss a detailed case summary, explore management options, and evaluate the treatment outcomes.
CASE SUMMARYWe report on a pair of siblings, a 24-year-old male and a 19-year-old female, who were born encased in a collodion membrane, and later presented with large, brown, plate-like scales all over the body. Skin changes were accompanied by intermittent heat intolerance and mild ectropion, which subsequently caused impaired quality of life while growing up. Histopathology results were consistent with lamellar ichthyosis. Both siblings responded well to oral Acitretin at 0.5 mglkglday, showing significant shedding of thick scales and a reduction of ectropion within the first two weeks of therapy.
CONCLUSIONLamellar ichthyosis, a severe, lifelong disorder with psychosocial repercussions, requires long-standing, continual therapy. Maximizing treatment options with oral acitretin, addressing the psychosocial implications of the disease and getting patients actively involved in its management results in better treatment outcomes.
Human ; Male ; Female ; Young Adult: 19-24 Yrs Old ; Ichthyosis, Lamellar ; Acitretin
7.Commentary: polymer binding modules accelerate enzymatic degradation of poly(ethylene terephthalate).
Yi LU ; Ruizhi HAN ; Ulrich SCHWANEBERG ; Yu JI
Chinese Journal of Biotechnology 2023;39(5):1883-1888
The large scale production and indiscriminate use of plastics led to serious environmental pollution. To reduce the negative effects of plastics waste on the environment, an approach of enzymatic degradation was put forward to catalyze plastics degradation. Protein engineering strategies have been applied to improve the plastics degrading enzyme properties such as activity and thermal stability. In addition, polymer binding modules were found to accelerate the enzymatic degradation of plastics. In this article, we introduced a recent work published in Chem Catalysis, which studied the role of binding modules in enzymatic hydrolysis of poly(ethylene terephthalate) (PET) at high-solids loadings. Graham et al. found that binding modules accelerated PET enzymatic degradation at low PET loading (< 10 wt%) and the enhanced degradation cannot be observed at high PET loading (10 wt%-20 wt%). This work is beneficial for the industrial application of polymer binding modules in plastics degradation.
Polyethylene Terephthalates/metabolism*
;
Polymers
;
Plastics
;
Ethylenes
8.Polyethylene biodegradation: current status and perspectives.
Liting ZHANG ; Bo ZHANG ; Weidong XU ; Zhongli CUI ; Hui CAO
Chinese Journal of Biotechnology 2023;39(5):1949-1962
Polyethylene (PE) is the most abundantly used synthetic resin and one of the most resistant to degradation, and its massive accumulation in the environment has caused serious pollution. Traditional landfill, composting and incineration technologies can hardly meet the requirements of environmental protection. Biodegradation is an eco-friendly, low-cost and promising method to solve the plastic pollution problem. This review summarizes the chemical structure of PE, the species of PE degrading microorganisms, degrading enzymes and metabolic pathways. Future research is suggested to focus on the screening of high-efficiency PE degrading strains, the construction of synthetic microbial consortia, the screening and modification of degrading enzymes, so as to provide selectable pathways and theoretical references for PE biodegradation research.
Polyethylene/metabolism*
;
Bacteria/metabolism*
;
Plastics/metabolism*
;
Biodegradation, Environmental
;
Microbial Consortia
9.Advances in poly(ethylene terephthalate) hydrolases.
Zhiyi ZHAO ; Guoqiang ZHANG ; Kun LIU ; Shengying LI
Chinese Journal of Biotechnology 2023;39(5):1998-2014
Plastics have brought invaluable convenience to human life since it was firstly synthesized in the last century. However, the stable polymer structure of plastics led to the continuous accumulation of plastic wastes, which poses serious threats to the ecological environment and human health. Poly(ethylene terephthalate) (PET) is the most widely produced polyester plastics. Recent researches on PET hydrolases have shown great potential of enzymatic degradation and recycling of plastics. Meanwhile, the biodegradation pathway of PET has become a reference model for the biodegradation of other plastics. This review summarizes the sources of PET hydrolases and their degradation capacity, degradation mechanism of PET by the most representative PET hydrolase-IsPETase, and recently reported highly efficient degrading enzymes through enzyme engineering. The advances of PET hydrolases may facilitate the research on the degradation mechanism of PET and further exploration and engineering of efficient PET degradation enzymes.
Humans
;
Hydrolases/metabolism*
;
Polyethylene Terephthalates/metabolism*
;
Plastics/metabolism*
;
Ethylenes
10.Expression, purification and characterization of a novel bis (hydroxyethyl) terephthalate hydrolase from Hydrogenobacter thermophilus.
Yangyang CHEN ; Jian GAO ; Yipei ZHAO ; Hao WANG ; Xu HAN ; Jie ZHANG ; Qun GU ; Ying HOU ; Weidong LIU
Chinese Journal of Biotechnology 2023;39(5):2015-2026
PET (polyethylene terephthalate) is one of the most important petrochemicals that is widely used in mineral water bottles, food and beverage packaging and textile industry. Because of its stability under environmental conditions, the massive amount of PET wastes caused serious environmental pollution. The use of enzymes to depolymerize PET wastes and upcycling is one of the important directions for plastics pollution control, among which the key is the depolymerization efficiency of PET by PET hydrolase. BHET (bis(hydroxyethyl) terephthalate) is the main intermediate of PET hydrolysis, its accumulation can hinder the degradation efficiency of PET hydrolase significantly, and the synergistic use of PET hydrolase and BHET hydrolase can improve the PET hydrolysis efficiency. In this study, a dienolactone hydrolase from Hydrogenobacter thermophilus which can degrade BHET (HtBHETase) was identified. After heterologous expression in Escherichia coli and purification, the enzymatic properties of HtBHETase were studied. HtBHETase shows higher catalytic activity towards esters with short carbon chains such as p-nitrophenol acetate. The optimal pH and temperature of the reaction with BHET were 5.0 and 55 ℃, respectively. HtBHETase exhibited excellent thermostability, and retained over 80% residual activity after treatment at 80 ℃ for 1 hour. These results indicate that HtBHETase has potential in biological PET depolymerization, which may facilitate the enzymatic degradation of PET.
Hydrolases/metabolism*
;
Bacteria/metabolism*
;
Hydrolysis
;
Polyethylene Terephthalates/metabolism*


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