Severe Staphylococcus lugdunensis keratitis.

We report a severe case of Staphylococcus lugdunensis (S. lugdunensis) keratitis presenting as suppurative keratitis in a 77-year-old woman. The patient's chief complaint was eye pain and decreased visual acuity in her right eye. Suppurative keratitis with a severe corneal abscess was diagnosed by a slit-lamp ophthalmic examination. The causative organism was identified as S. lugdunensis by bacterial culture, using a corneal abrasion specimen. She was treated with an intravenous drip infusion of ceftazidime and instillation of gentamicin sulfate ophthalmic solution (six times daily) and ofloxacin ophthalmic ointment (once daily before bedtime) as empiric therapy. Her hospital course was complicated by a corneal perforation of her right eye. The antibiotic susceptibility for S. lugdunensis was sensitive, but with a slightly high MIC for antibiotics used in empiric therapy. The therapeutic drug was changed to levofloxacin ophthalmic solution. The corneal abscess left a scar after healing. Representative causative organisms of suppurative keratitis include Pseudomonas aeruginosa and Streptococcus pneumoniae, but care must be taken in cases involving rare causative organisms. Empiric therapy is necessary for rapidly progressing suppurative keratitis, but a detailed examination of the causative organism is important for therapeutic planning before empiric therapy.

Molecular-scale surface structures of oligo(ethylene glycol)-terminated self-assembled monolayers investigated by frequency modulation atomic force microscopy in aqueous solution.

The structure and protein resistance of oligo(ethylene glycol)-terminated self-assembled monolayers (OEG-SAMs) have been studied intensively using various techniques. However, their molecular-scale surface structures have not been well understood. In this study, we performed molecular-resolution imaging of OH-terminated SAMs (OH-SAMs) and hexa(ethylene glycol) SAMs (EG(6)OH-SAMs) formed on a Au(111) surface in an aqueous solution by frequency modulation atomic force microscopy (FM-AFM). The results show that most of the ethylene glycol (EG) chains in an EG(6)OH-SAM are closely packed and well-ordered to present a molecularly flat surface even in an aqueous solution. In addition, we found that EG(6)OH-SAMs have nanoscale defects, where molecules take a disordered arrangement with their molecular axes parallel to the substrate surface. We also found that the domain size (50-200 nm) of an EG(6)OH-SAM is much larger than that of OH-SAMs (10-40 nm). These findings should significantly advance molecular-scale understanding about the surface structure of OEG-SAMs.

A proof-of-principle for decontamination of transplantation kidney through UV-C exposition of the perfusate solution.

Kidney transplantation is a common yet highly demanding medical procedure worldwide, enhancing the quality of life for patients with chronic kidney disease. Despite its prevalence, the procedure faces a shortage of available organs, partly due to contamination by microorganisms, leading to significant organ disposal. This study proposes utilizing photonic techniques associated with organ support machines to prevent patient contamination during kidney transplantation. We implemented a decontamination system using ultraviolet-C (UV-C) irradiation on the preservation solution circulating through pigs' kidneys between harvest and implant. UV-C irradiation, alone or combined with ultrasound (US) and Ps80 detergent during ex-vivo swine organ perfusion in a Lifeport® Kidney Transporter machine, aimed to reduce microbiological load in both fluid and organ. Results show rapid fluid decontamination compared to microorganism release from the organ, with notable retention. By including Ps80 detergent at 0.5% during UV-C irradiation 3 log10 (CFU mL-1) of Staphylococcus aureus bacteria previously retained in the organ were successfully removed, indicating the technique's feasibility and effectiveness.

Quantitative autistic traits ascertained in a national survey of 22 529 Japanese schoolchildren.

OBJECTIVE: Recent epidemiologic studies worldwide have documented a rise in prevalence rates for autism spectrum disorders (ASD). Broadening of diagnostic criteria for ASD may be a major contributor to the rise in prevalence, particularly if superimposed on an underlying continuous distribution of autistic traits. This study sought to determine the nature of the population distribution of autistic traits using a quantitative trait measure in a large national population sample of children. METHOD: The Japanese version of the Social Responsiveness Scale (SRS) was completed by parents on a nationally representative sample of 22 529 children, age 6-15. RESULTS: Social Responsiveness Scale scores exhibited a skewed normal distribution in the Japanese population with a single-factor structure and no significant relation to IQ within the normal intellectual range. There was no evidence of a natural 'cutoff' that would differentiate populations of categorically affected children from unaffected children. CONCLUSION: This study provides evidence of the continuous nature of autistic symptoms measured by the SRS, a validated quantitative trait measure. The findings reveal how paradigms for diagnosis that rest on arbitrarily imposed categorical cutoffs can result in substantial variation in prevalence estimation, especially when measurements used for case assignment are not standardized for a given population.

Clinical study of anogenital condyloma acuminata treatment with photodynamic therapy including immunocompromised conditions.

Human Papillomavirus (HPV) infection is highly prevalent worldwide, and one of its consequences is the external genital wart, or Condyloma Acuminata (CA). The present study used Photodynamic Therapy (PDT) to treat CA lesions. PDT treated 23 patients with a clinical diagnosis of multifocal and unifocal CA. Patients were divided into Group 1 (G1, Patients without pathologies associated with immunodeficiency) and Group 2 (G2, patients with pathologies associated with immunodeficiency). In the G1 group (19 patients), PDT resulted in a Complete Response in 68.4% (average 5 PDT cycles), Partial Response in 26.3% (average 10 PDT cycles), and No Response in 5.3% (average 6 PDT cycles). In the G2 group (4 patients), 100% of subjects showed a partial response (8 PDT cycles). These patients in the G2 and with partial response had associated pathologies, such as renal failure, breast cancer, and HIV. There was a slight decrease in lesions (20-40%) post-treatment in these cases. Four months after treatment, no new lesions or recurrence were observed in the entire area treated with PDT using low doses of PDT. Eighty-six percent of the patients tolerated the treatments well. We conclude that PDT is a promising and safe treatment for CA lesions compared to traditional treatments.

In vitro evaluation of the cis-[Ru(phen)2(pPDIp)]2+⁎⁎ complex for antimicrobial photodynamic therapy against Sporothrix brasiliensis and Candida albicans.

BACKGROUND: Photodynamic therapy (PDT) activates a photosensitizer by visible light to generate cytotoxic oxygen species that lead to cell death. With proper illumination, PDT is often used in applications on superficial and sub-surface lesions. Sporotrichosis infection occurs by Sporothrix fungi which causes a skin wound, worsened by Candida albicans infections. This study investigated the photosensitizing efficiency of the Ru(phen)2(pPDIp)(PF6)2 complex, RupPDIp, against S. brasiliensis and C. albicans. MATERIAL AND METHODS: RupPDIp efficiency against these fungi was tested using 450 nm (blue light and 36 J/cm2) and 525 nm (green light, 25.2 J/cm2) at 0.05-20 µM concentrations. To ensure PDT effectiveness, control groups were tested in the absence and in the presence of RupPDIp under light irradiation and in the dark. RESULTS: RupPDIp eliminated both fungi at ≤5.0 µM. Green light showed the best results, eliminating S. brasiliensis and C. albicans colonies at RupPDIp 0.5 µM and 0.05 µM, respectively. CONCLUSION: RupPDIp is a promising photosensitizer in aPDT, eliminating 106 CFU/mL of both fungi at 450 nm and 525 nm, with lower light doses and concentrations when treated with the green light compared to the blue light.

Mechanism of Trypanosoma cruzi death induced by Cratylia mollis seed lectin.

Incubation of T. cruzi epimastigotes with the lectin Cramoll 1,4 in Ca(2+) containing medium led to agglutination and inhibition of cell proliferation. The lectin (50 microg/ml) induced plasma membrane permeabilization followed by Ca(2+) influx and mitochondrial Ca(2+) accumulation, a result that resembles the classical effect of digitonin. Cramoll 1,4 stimulated (five-fold) mitochondrial reactive oxygen species (ROS) production, significantly decreased the electrical mitochondrial membrane potential (Delta Psi(m)) and impaired ADP phosphorylation. The rate of uncoupled respiration in epimastigotes was not affected by Cramoll 1,4 plus Ca(2+) treatment, but oligomycin-induced resting respiration was 65% higher in treated cells than in controls. Experiments using T. cruzi mitochondrial fractions showed that, in contrast to digitonin, the lectin significantly decreased Delta Psi(m) by a mechanism sensitive to EGTA. In agreement with the results showing plasma membrane permeabilization and impairment of oxidative phosphorylation by the lectin, fluorescence microscopy experiments using propidium iodide revealed that Cramoll 1,4 induced epimastigotes death by necrosis.

Photonic effects in natural nanostructures on Morpho cypris and Greta oto butterfly wings.

Photonic crystals are some of the more spectacular realizations that periodic arrays can change the behavior of electromagnetic waves. In nature, so-called structural colors appear in insects and even plants. Some species create beautiful color patterns as part of biological behavior such as reproduction or defense mechanisms as a form of biomimetics. The interaction between light and matter occurs at the surface, producing diffraction, interference and reflectance, and light transmission is possible under suitable conditions. In particular, there are two Colombian butterflies, Morpho cypris and Greta oto, that exhibit iridescence phenomena on their wings, and in this work, we relate these phenomena to the photonic effect. The experimental and theoretical approaches of the optical response visible region were studied to understand the underlying mechanism behind the light-matter interaction on the wings of these Colombian butterflies. Our results can guide the design of novel devices that use iridescence as angular filters or even for cosmetic purposes.

Uncoupling and oxidative stress in liver mitochondria isolated from rats with acute iron overload.

One hypothesis for the etiology of cell damage arising from iron overload is that its excess selectively affects mitochondria. Here we tested the effects of acute iron overload on liver mitochondria isolated from rats subjected to a single dose of i.p. 500 mg/kg iron-dextran. The treatment increased the levels of iron in mitochondria (from 21 +/- 4 to 130 +/- 7 nmol/mg protein) and caused both lipid peroxidation and glutathione oxidation. The mitochondria of iron-treated rats showed lower respiratory control ratio in association with higher resting respiration. The mitochondrial uncoupling elicited by iron-treatment did not affect the phosphorylation efficiency or the ATP levels, suggesting that uncoupling is a mitochondrial protective mechanism against acute iron overload. Therefore, the reactive oxygen species (ROS)/H+ leak couple, functioning as a mitochondrial redox homeostatic mechanism could play a protective role in the acutely iron-loaded mitochondria.

Norovirus recovery from floors and air after various decontamination protocols.

BACKGROUND: The dispersal of airborne norovirus (NoV) particles from the floor after contamination with faeces or vomit is a challenge for infection control, as this pathogen is infectious at low doses. Therefore, it is imperative to establish a safe protocol for floor decontamination. AIM: To assess the presence of residual NoV-GII particles on floors and airborne particles following various floor decontamination procedures. METHODS: Two types of floor (vinyl and granite) were contaminated intentionally with 10% human faeces, positive for NoV-GII. Two decontamination protocols were implemented: cleaning followed by disinfection using 1% sodium hypochlorite, and cleaning followed by disinfection using a manual ultraviolet C (UV-C) light device. Swab samples were taken from the floors, and air samples were obtained using an air sampler. The TaqMan method for real-time reverse transcription-quantitative polymerase chain reaction was employed for analysis. FINDINGS: The disinfection protocol using 1% sodium hypochlorite after cleaning proved to be more effective than cleaning followed by UV-C light exposure (P<0.001). Viral particles were detected in 27 of 36 air samples after cleaning, with no significant difference between the two floor types. On average, 617 genome copies/sample were identified in air samples after cleaning, but the number decreased gradually after disinfection. CONCLUSION: NoV-GII can be aerosolized during floor cleaning, and its particles may be inhaled and then swallowed or can settle on surfaces. Therefore, residual viral particles on floors must be fully eliminated. Cleaning followed by 10 min of 1% sodium hypochlorite disinfection proved to be the superior decontamination protocol.

Calreticulin mutant mice develop essential thrombocythemia that is ameliorated by the JAK inhibitor ruxolitinib.

Mutations of calreticulin (CALR) are detected in 25-30% of patients with essential thrombocythemia (ET) or primary myelofibrosis and cause frameshifts that result in proteins with a novel C-terminal. We demonstrate that CALR mutations activated signal transducer and activator of transcription 5 (STAT5) in 293T cells in the presence of thrombopoietin receptor (MPL). Human megakaryocytic CMK11-5 cells and erythroleukemic F-36P-MPL cells with knocked-in CALR mutations showed increased growth and acquisition of cytokine-independent growth, respectively, accompanied by STAT5 phosphorylation. Transgenic mice expressing a human CALR mutation with a 52 bp deletion (CALRdel52-transgenic mice (TG)) developed ET, with an increase in platelet count, but not hemoglobin level or white blood cell count, in association with an increase in bone marrow (BM) mature megakaryocytes. CALRdel52 BM cells did not drive away wild-type (WT) BM cells in in vivo competitive serial transplantation assays, suggesting that the self-renewal capacity of CALRdel52 hematopoietic stem cells (HSCs) was comparable to that of WT HSCs. Therapy with the Janus kinase (JAK) inhibitor ruxolitinib ameliorated the thrombocytosis in TG mice and attenuated the increase in number of BM megakaryocytes and HSCs. Taken together, our study provides a model showing that the C-terminal of mutant CALR activated JAK-STAT signaling specifically downstream of MPL and may have a central role in CALR-induced myeloproliferative neoplasms.

Induced mutations in M13mp2 phage DNA exposed to N-nitrosopyrrolidine with UVA irradiation.

It is known that N-nitrosopyrrolidine (NPYR), a carcinogen in rodents, is metabolically activated by microsomal cytochrome P450 to form an alpha-hydroxylated derivative, which induces mutations. The mutations have been demonstrated by use of Salmonella typhimurium and Escherichia coli. We discovered directly acting mutagenicity of NPYR plus ultraviolet light-A (UVA) in bacteria and phage. With an O(6)-alkyltransferase-deficient strain of S.typhimurium, the NPYR plus UVA treatment gave greater mutation frequencies compared to those found with the parent strain. We identified the structure of the direct-acting mutagen as N-nitroso-1-phosphonooxypyrrolidine, and analyzed the spectrum of mutations induced in the DNA of M13mp2 phage. The basepair substitutions GC to TA and GC to AT appear to occur predominantly. Several hotspots were observed. In the conditions where SOS response was induced in the host E.coli, greater varieties of mutations were observed in phage DNA compared to those without the SOS response induction. These results suggest that alkylations of DNA occur by the photoactivated NPYR. The roles of the produced damage to the mutations are discussed.

Iron-chlorophyllin-mediated conversion of 3-hydroxyamino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2(NHOH)) into its nitroso derivative.

Early work from our laboratory has shown that the mutagenicity of heterocyclic amines in Salmonella can be inhibited by hemin and chlorophyllins. We have speculated that the inhibition is a result of complex formation between heterocyclic amines and the pigments, and the speculation has been given a line of experimental evidence. We have now found that ferric-chlorophyllin (Fe-chlorophyllin) can modify the mutagenicity of 3-hydroxyamino-1-methyl-5H-pyrido[4, 3-b]indole (Trp-P-2(NHOH)), a metabolically activated form of 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2). The mutagenicity of Trp-P-2(NHOH) in Salmonella typhimurium TA 98 (without S9) was strongly inhibited by an addition of an equimolar Fe-chlorophyllin in the pre-incubation mixture. Fe-chlorophyllin also inhibited the mutagenicity of 2-hydroxyamino-6-methyldipyrido[1,2-a:3',2'-d] imidazole (Glu-P-1(NHOH)). A rapid change in the UV spectrum of a mixture of Trp-P-2(NHOH) and Fe-chlorophyllin was observed. Analysis by high performance liquid chromatography showed that Trp-P-2(NHOH) was converted into 3-nitroso-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2(NO)), the mutagenic potency of which is a quarter of that of Trp-P-2(NHOH). Furthermore, the mutagenicity of Trp-P-2(NO), in turn, was inhibited by Fe-chlorophyllin. We conclude that the suppression of the mutagenicity of Trp-P-2(NHOH) is ascribable to the oxidative function of Fe-chlorophyllin, coupled with its ability to form complex formation with the planar surface of the heterocyclic amine molecules.

Immunosuppressive effect of cholera toxin B on allergic conjunctivitis model in guinea pig.

PURPOSE: To investigate the new method of immunotherapy using cholera toxin B (CTB) in experimental allergic conjunctivitis. METHODS: We used 21 white Hartley guinea pigs. The animals were sensitized by intraperitoneal injection of ovalbumin (100 microg/mL) and albumin hydroxide (5 mg/mL) repeated after an interval of 2 weeks. One week after the second injection, conjunctivitis was induced by topical instillation of ovalbumin (5 mg/mL). The animals were divided into two groups, CTB group and control group. The CTB group underwent pretreatment of topical instillation of CTB (4 microg/30 mL) and ovalbumin (10 microg/30 mL), three times a day for 3 days, 1 week before the intraperitoneal injection. The control group did not undergo the pretreatment. Clinical examination was performed at 0.5, 6, and 24 hours after the development of conjunctivitis. Histological examination was performed at 6 and 24 hours. RESULTS: Both groups developed palpebral and bulbar edema with hyperemia 30 minutes after instillation of ovalbumin. The allergic reaction score was significantly less in the CTB group than in the control group (Mann-Whitney U-test: P <.01). The clinical reactions subsided after 6 hours. The CTB group showed less eosinophilic infiltration in the conjunctiva and the limbus, particularly in the conjunctival epithelium, than the control group at 6 and 24 hours. CONCLUSION: Pretreatment with topical CTB and antigen suppresses clinical and histological findings in experimentally induced allergic conjunctivitis.

Immunohistochemical study on follicular dendritic cell of conjunctiva-associated lymphoid tissue.

We performed an immunohistochemical study of follicular dendritic cells (FDC) in the follicular area of the conjunctiva-associated lymphoid tissue (CALT). Hartley guinea pigs were sensitized with a topical application of an emulsion of ovalbumin and Freund's complete adjuvant in the eye. They were divided into four groups. The control (group A) underwent no sensitization. The sensitized animals were studied at 1 week (group B1) or 2 weeks (group B2) after the sensitization. Additional sensitization at 1 week after the initial sensitization was also performed (group C). Histological methods included methylgreen pyronine staining, alpha-naphthylacetate esterase staining, and enzyme-antibody method against S-100 protein. The uptake of topically applied peroxidase-anti-peroxidase (PAP) in CALT was also examined histologically. In each group, positive reticular patterns by alphanaphthyl acetate esterase staining and immunoperoxidase staining with anti-S-100 protein antiserum were found in the CALT follicular area. The positively stained cells were found to be dendrite cells by immunoelectronmicroscopy. An uptake of PAP was found in the CALT follicular area, suggesting the function of trapping and retaining antigen-antibody complex by FDC. It was concluded that dendritic cells in the CALT follicular area were identified to be FDC.

[Distribution of S-100 protein positive cells in conjunctiva].

We compared the distribution of S-100 protein positive cells in normal conjunctiva and in an induced allergic conjunctivitis model using Hartley strain guinea pigs. The animals were sensitized by intraperitoneal injection of ovoalbumin solution with hydroxy aluminum, followed by topical application of the ovoalbumin solution. The primary antibody was antibovine brain S-100 positive antibody, detected by the avidin biotin complex method. S-100 positive cells were present at the limbal corneal epithelium and on the skin of the palpebrae in both the normal group and the allergic conjunctivitis group, indicating the presence of Langerhans cells. In the allergic group, positive cells were also detected in palpebral conjunctiva and the germinal centers of conjunctival follicles. These cells were identified as follicular dendritic cells or interdigitating cells. In conclusion antigen presenting cells were present in the limbal conjunctiva, follicular and parafollicular area of conjunctival follicles, and palpebral skin in the allergic conjunctivitis models.

[A morphological study of lymphocyte homing in conjunctiva-associated lymphoid tissue].

High endothelial venule (HEV) is an important component of the mucosa-associated lymphoid tissue and plays a role in the homing phenomenon of lymphocytes. We investigated the presence of HEVs in conjunctiva-associated lymphoid tissue (CALT) using guinea pigs sensitized with ovalbumin. Electron microscopy showed characteristic findings for HEVs in the parafollicular area of the CALT. Lymphocytes in the vessels are trapped not only by microprocesses extending from the vascular endothelium but also by the endothelial cells. Some endothelial cells also appear to release lymphocytes. We conclude that HEVs are present also in the CALT.

[Histological study of the effect of conjunctival transplantation on rabbit cornea with alkali burned].

PURPOSE: A histopathological study to investigate the efficacy of conjunctival auto-transplantation on alkaline chemical burns of the ocular surface. MATERIAL AND METHODS: An alkaline chemical burn model was developed in one eye of rabbits using 0.1 N NaOH solution. In one group conjunctival transplantation was performed. A control group did not receive conjunctival transplantation. A histological follow-up study was performed by light microscopy with hematoxylin eosin stain and periodic acid Schiff staining by fluoro-microscopy using epithelial Keratin-AE 5 antibody, and by transmission electron microscopy(TEM). RESULTS: The transplanted group showed scar formation between the transplanted conjunctival tissue and the sclera. At 20 days and 8 weeks after the transplantation, neovascularization and cell infiltration in the subepithelium of the limbus was decreased compared with the transplanted group at 10 days. The control group showed a decrease of cell infiltration in the limbal area compared with the group at 10 days, but conjunctival tissue with thick collagenous tissue and neovascularization instead of scar tissue developed on the injured cornea. AE 5 positive cells were not found in the limbus in either group. In the transplanted group, in TEM, the basement membrane of transplanted conjunctiva showed less irregularity, and degenerated fibroblasts were present at the margin of the scar tissue. In the control group, the basement membrane of the conjunctiva showed an irregular pattern and fibroblasts beneath the conjunctival epithelium had large nuclei. CONCLUSION: In the transplanted group, scar tissue developed and suppressed cell infiltration, neovascularization, and conjunctival tissue in the injured cornea and secured re-structuring of the limbal tissue.

[Histological study of allergic conjunctivitis--1. Study on the adhesion molecules to allergic conjunctivitis].

We performed an immunohistochemical study on the relationship between inflammatory cells and adhesion molecules to investigate inflammatory reaction in allergic conjunctivitis. Guinea pigs were sensitized with an intraperitoneal injection of ovalbumin with hydroxyalminium. Ovalbumin was applied topically to the conjunctiva 3 weeks after the initial treatment. Then the cornea, conjunctiva and lacrymal gland were taken and processed for frozen sections. The specimens were stained with acid Giemsa for inflammatory cells and enzyme-labelled antibody for ICAM-1 and VCAM-1. Neutrophils were dominantly observed 6 hours after the challenge with the antigen, eosinophils at 12 hours, and eosinophils and lymphocytes at 24 hours, respectively. ICAM-1 and VCAM-1 were detected at 6 and 24 hours in the vascular tissue in the subconjunctival tissue and lacrymal gland. There results suggest that adhesion molecules play a role in the infiltration of inflammatory cells in allergic conjunctivitis.