Skin Microorganisms Research Articles

Preservative Effect of Chitosan with 1,3-Butylene Glycol as Natural Preservativein Cosmetic Formulation

This study was to evaluate the preservative effect of chitosan with 1,3-butylene glycol as natural preservative in cosmetic formulation. Antibacterial activity was measured by disc diffusion assay and broth microdilution assay were assessed on human skin microorganisms, Staphylococcus aureus, methicillin-resistant Staphylococcus aureus, and Escherichia coli. Antioxidant activity was measured by DPPH radical scavenging assay. Furthermore, an optimum formulation of chitosan with 1,3-butylene glycol was confirmed the preservative effect and cytotoxicity through challenge test and cell cytotoxicity assay. Chitosan showed remarkable antibacterial and antioxidant activities. A combination of chitosan with 1,3-butylene glycol exhibited higher activity compared to chitosan alone. Through results, the optimum formulation was determined to 156 μg/mL chitosan with 10% 1,3-butylene glycol (CTSN-BG). CTSN-BG showed a potent preservative effect and non-cytotoxicity on HaCaT and HEK 293 cells. In conclusion, the results demonstrated that CTSN-BG may be useful in a wide range of substitutes for chemical preservatives in cosmetic industry.

Preservative Effect of Chitosan with 1,3-Butylene Glycol as Natural Preservativein Cosmetic Formulation

This study was to evaluate the preservative effect of chitosan with 1,3-butylene glycol as natural preservative in cosmetic formulation. Antibacterial activity was measured by disc diffusion assay and broth microdilution assay were assessed on human skin microorganisms, Staphylococcus aureus, methicillin-resistant Staphylococcus aureus, and Escherichia coli. Antioxidant activity was measured by DPPH radical scavenging assay. Furthermore, an optimum formulation of chitosan with 1,3-butylene glycol was confirmed the preservative effect and cytotoxicity through challenge test and cell cytotoxicity assay. Chitosan showed remarkable antibacterial and antioxidant activities. A combination of chitosan with 1,3-butylene glycol exhibited higher activity compared to chitosan alone. Through results, the optimum formulation was determined to 156 μg/mL chitosan with 10% 1,3-butylene glycol (CTSN-BG). CTSN-BG showed a potent preservative effect and non-cytotoxicity on HaCaT and HEK 293 cells. In conclusion, the results demonstrated that CTSN-BG may be useful in a wide range of substitutes for chemical preservatives in cosmetic industry.

Systemic lupus erythematosus patients have a distinct structural and functional skin microbiota compared with controls.

The skin is the second most affected organ after articular involvement in systemic lupus erythematosus (SLE) patients. Cutaneous involvement occurs in approximately 80% of patients during the course of SLE. Interaction between the host and skin microorganism is a complex process. There are few studies on the diversity of skin microbes in SLE patients. Therefore, this study aims to explore the relationship between skin microorganisms and SLE. A total of 20 SLE patients, 20 controls with rosacea and 20 healthy controls were selected as study subjects. Both the skin microbiota of rash region and non-rash region for each SLE patient were collected.16S rRNA gene sequencing was used to detected skin microbiota from 80 specimens. α-Diversity and β-diversity of skin microbiota were analyzed based on operational taxonomic units (OTUs) and minimal entropy decomposition (MED). Using Wilcoxon test and Linear Discriminate Analysis Effect Size (LEfSe), skin microbial diversity and composition were analyzed. Functional capabilities of microbiota were estimated through Kyoto Encyclopedia of Genes and Genomes database. Compared to rash region of SLE, diversity and richness were increased in healthy controls, and decreased in non-rash region of SLE and rash region of controls with rosacea. Additionally, changes of skin microbial composition were found at different taxonomic levels between four groups. For example, genus Halomonas was increased and genera Pelagibacterium, Novosphingobium, and Curvibacter were decreased in rash region compared to non-rash region of SLE based on OTUs and MED. Based on OTUs, metabolic pathways were also found differences in SLE patients, such as Xenobiotics Biodegradation and Metabolism. Compositions and diversity of skin microbiota in SLE patients are changed. This pilot study provides some suggestive evidence for further exploration of skin microbiota in SLE patients with cutaneous involvement.

Nationality and body location alter human skin microbiome.

Skin microbiomes function directly in human health and are affected by various external and internal factors. However, few studies have showed the variation of human skin microbiota at multiple body sites in individuals of different national origin living in the same environment. Here, using 16S rRNA sequencing, we investigated the diversity and function of skin microbiomes in different body locations of Chinese and Pakistani individuals from a single college in China. Body location and nationality significantly affected community structures, while season and gender only impacted community member. Due to different lifestyles and likely genetic characteristics of the hosts, Proteobacteria was more abundant in Pakistanis than in Chinese individuals. There were significant differences in the Shannon diversity of skin microorganisms among different skin sites of Chinese individuals, but not in Pakistanis. PICRUSt prediction indicated that gene functions involved in carbohydrate metabolism, lipid metabolism, and xenobiotics biodegradation and metabolism were higher in bacteria collected from Pakistanis than those from Chinese individuals, but the amino acid metabolism of skin microorganisms in Chinese people was higher. The relative abundances of potential pathogenic bacteria also differed in different body locations, providing a foundation for studying skin-associated bacterial diseases. Through a meta-analysis of 233 human skin samples from eight elevational sites in western China, we found that skin microbial diversity first decreased and then increased with increasing altitude. Network analysis showed positive correlation between altitude and Lactobacillus, Chryseobacterium, or Acinetobacter. Our results uncover the variation of human skin microbiota allowing future explorations of potential significance for human health. KEY POINTS: • Body location and nationality affect skin microbiota diversity and function. • Proteobacteria was more abundant in Pakistanis than in Chinese. • Skin microbial diversity first decreased and then increased with elevated altitude.

BCLA CLEAR - Contact lens complications

Contact lens-related complications are common, affecting around one third of wearers, although most are mild and easily managed. Contact lenses have well-defined anatomical and physiological effects on the ocular surface and can result in other consequences due to the presence of a biologically active material. A contact lens interacts with the tear film, ocular surface, skin, endogenous and environmental microorganisms, components of care solutions and other antigens which may result in disease specific to contact lens wear, such as metabolic or hypersensitivity disorders. Contact lens wear may also modify the epidemiology or pathophysiology of recognised conditions, such as papillary conjunctivitis or microbial keratitis. Wearers may also present with intercurrent disease, meaning concomitant or pre-existing conditions unrelated to contact lens wear, such as allergic eye disease or blepharitis, which may complicate the diagnosis and management of contact lens-related disease.Complications can be grouped into corneal infection (microbial keratitis), corneal inflammation (sterile keratitis), metabolic conditions (epithelial: microcysts, vacuoles, bullae, tight lens syndrome, epithelial oedema; stromal: superficial and deep neovascularisation, stromal oedema [striae/folds], endothelial: blebs, polymegethism/ pleomorphism), mechanical (corneal abrasion, corneal erosion, lens binding, warpage/refractive error changes; superior epithelial arcuate lesion, mucin balls, conjunctival epithelial flaps, ptosis, discomfort), toxic and allergic disorders (papillary conjunctivitis, solution-induced corneal staining, incomplete neutralisation of peroxide, Limbal Stem Cell Deficiency), tear resurfacing disorders/dry eye (contact lens-induced dry eye, Meibomian gland dysfunction, lid wiper epitheliopathy, lid parallel conjunctival folds, inferior closure stain, 3 and 9 o'clock stain, dellen, dimple veil) or contact lens discomfort. This report summarises the best available evidence for the classification, epidemiology, pathophysiology, management and prevention of contact lens-related complications in addition to presenting strategies for optimising contact lens wear.

A mixed community of skin microbiome representatives influences cutaneous processes more than individual members

BackgroundSkin, the largest organ of the human body by weight, hosts a diversity of microorganisms that can influence health. The microbial residents of the skin are now appreciated for their roles in host immune interactions, wound healing, colonization resistance, and various skin disorders. Still, much remains to be discovered in terms of the host pathways influenced by skin microorganisms, as well as the higher-level skin properties impacted through these microbe-host interactions. Towards this direction, recent efforts using mouse models point to pronounced changes in the transcriptional profiles of the skin in response to the presence of a microbial community. However, there is a need to quantify the roles of microorganisms at both the individual and community-level in healthy human skin. In this study, we utilize human skin equivalents to study the effects of individual taxa and a microbial community in a precisely controlled context. Through transcriptomics analysis, we identify key genes and pathways influenced by skin microbes, and we also characterize higher-level impacts on skin processes and properties through histological analyses.ResultsThe presence of a microbiome on a 3D skin tissue model led to significantly altered patterns of gene expression, influencing genes involved in the regulation of apoptosis, proliferation, and the extracellular matrix (among others). Moreover, microbiome treatment influenced the thickness of the epidermal layer, reduced the number of actively proliferating cells, and increased filaggrin expression. Many of these findings were evident upon treatment with the mixed community, but either not detected or less pronounced in treatments by single microorganisms, underscoring the impact that a diverse skin microbiome has on the host.ConclusionsThis work contributes to the understanding of how microbiome constituents individually and collectively influence human skin processes and properties. The results show that, while it is important to understand the effect of individual microbes on the host, a full community of microbes has unique and pronounced effects on the skin. Thus, in its impacts on the host, the skin microbiome is more than the sum of its parts.F6Ez83UF8Q6ptotXK-unhhVideo abstract.

Analysis of Systemic and Cutaneous Inflammatory Immune Response in Canine Atopic Dermatitis

Background: Canine atopic dermatitis (CAD) is a chronic and inflammatory disease present in veterinary dermatological practice. The inflammation in CAD is triggered by environmental allergens and skin microorganisms, which are responsible for the worsening of cutaneous lesions. This continuous activation of skin inflammatory process can induce the production of free radicals that also contribute to cellular damage and ultimately leads to changes in blood parameters in dogs with CAD. Although there are reports of inflammatory parameters in CAD, there are a lack of studies correlating skin lesions, blood leukocytes and oxidative stress. Based on that,this study aimed to evaluate the integumentary and systemic inflammatory response in dogs with atopic dermatitis. Materials, Methods & Results: Dogs with confirmed diagnosis of canine atopic dermatitis (n = 10) were divided in two groups according to CADESI-IV: AI, with CADESI between 0-10, AII, with CADESI between 10-34, and control group (n = 5). Blood-biochemical and histological analysis were performed to access systemic and cutaneous inflammatory response. AII group tended to higher neutrophil and eosinophil counts, as well as neutrophil/lymphocyte ratio (NLR) when compared to AI. The albumin was lower in AII compared to AI and control (P < 0.05), while total bilirubin and malondialdehyde (MDA) did not differ between groups. NLR (r = 0.64 and P = 0.04) and MDA (r = 0.54 and P = 0.1) were positively correlated with CADESI, while albumin was negatively correlated with CADESI (r = -0.79 and P = 0.005). Histopathological analysis revealed a larger number of neutrophils, macrophages and mast cells in AI and AII than in control group (P < 0.05). Discussion: In this study it was possible to evaluate the systemic and cutaneous leukocyte dynamics in CAD. Skin inflammation induces the production of chemotactic molecules contribute to neutrophil outflow from blood vessel toward the affected tissue, which can be visualized as perivascular inflammatory infiltrate and exocytosis. At systemic level, there was a tendency to increase in total leukocytes and circulating neutrophil count in group AII, as well as in neutrophil/lymphocyte ratio (NLR), when compared to AI. The NLR is a widely available and inexpensive laboratory biomarker that quantifies systemic inflammation, being used in human medicine to evaluate prognosis in different types of cancer. In our study, dogs in AII group showed an increased NLR compared to AI and control, which demonstrates the influence of skin injury in systemic parameters. Furthermore, AII group is composed of dogs with greater lesion state, which reflects in higher NLR values. Since this disease is known by its chronicity and may remain stable for years, NLR may be a novel biomarker to evaluate acute exacerbation in CAD and could potentially explain why some patients have longer crisis duration and frequent flares. The maintenance of the inflammatory state also induces the production of oxidizing substances, which possibly exceed the total antioxidant capacity, generating a situation of oxidative stress, which can result in damage to membrane lipids and release of their products. MDA is reliable and is the most commonly used marker of the overall lipid peroxidation level and the presence of oxidative stress. This result may be related with the antioxidant system, such as albumin and bilirubin, which was able to promote an efficient control of oxidant substances. In conclusion, the presented data demonstrated an inflammatory process progression as well as introduced NLR as a potential marker of disease exacerbation in CAD.

Research progress on the potential delaying skin aging effect and mechanism of tea for oral and external use

Skin aging is characterized by the gradual loss of elasticity, the formation of wrinkles and various color spots, the degradation of extracellular matrix proteins, and the structural changes of the dermis. With the increasingly prominent problems of environmental pollution, social pressure, ozone layer thinning and food safety, skin problems have become more and more complex. The skin can reflect the overall health of the body. Skincare products for external use alone cannot fundamentally solve skin problems; it needs to improve the overall health of the body. Based on the literature review in recent 20 years, this paper systematically reviewed the potential delaying effect of tea and its active ingredients on skin aging by oral and external use. Tea is the second-largest health drink after water. It is rich in tea polyphenols, l-theanine, tea pigments, caffeine, tea saponins, tea polysaccharides and other secondary metabolites. Tea and its active substances have whitening, nourishing, anti-wrinkle, removing spots and other skincare effects. Its mechanism of action is ultraviolet absorption, antioxidant, anti-inflammatory, inhibition of extracellular matrix aging, inhibiting the accumulation of melanin and toxic oxidation products, balancing intestinal and skin microorganisms, and improving mood and sleep, among other effects. At present, tea elements skincare products are deeply loved by consumers. This paper provides a scientific theoretical basis for tea-assisted beauty and the high-end application of tea in skincare products.

Bacterial growth and recovery on hospital biometric devices: effect of two types of disinfectants.

Objectives:The aim of the study was to evaluate the presence of bacterial contamination on biometric identification devices in a public hospital; identify the species of bacteria implicated in the contamination and assess bacterial recovery after the use of 2 types of disinfectants: alcohol 70% and isopropyl alcohol chlorhexidine.Design:Before and after trial.Setting:Public hospital, tertiary referral center.Participants:All existing biometric identification devices in the hospital (n = 20).Methods:Collection of 2 microbiological samples from the fingerprint reading surface of biometric devices immediately before and after applying the solution with alcohol 70% and in separate time periods with isopropyl alcohol chlorhexidine.Results:It have been identified 21 different bacterial species in a total of 78 samples, mostly Staphylococcus epidermidis (32 samples) and S aureus (7 samples). S epidermidis was eliminated in 61.5% of the samples after disinfecting with alcohol 70% and in 92.3% of the samples disinfected with isopropyl alcohol chlorhexidine. S aureus was eliminated in 33.3% and 100% of the samples, respectively. We found no bacterial growth in 10% of the devices after disinfection with 70% alcohol and in 78.9% of devices after disinfection with isopropyl alcohol chlorhexidine. We also found that there was a decrease in the frequency of species isolated after using both disinfection solutions, although isopropyl alcohol chlorhexidine appeared to be more effective.Conclusions:The biometric identification devices used in this hospital seem to be safe regardless of the products used for its cleaning. The majority of the bacteria found are commensal skin microorganisms. We did not find pathogenic bacteria for immunocompetent individuals, in particular methicillin-resistant S aureus.

Staphylococcus epidermidis and Cutibacterium acnes: Two Major Sentinels of Skin Microbiota and the Influence of Cosmetics.

Dermatological and cosmetics fields have recently started to focus on the human skin microbiome and microbiota, since the skin microbiota is involved in the health and dysbiosis of the skin ecosystem. Amongst the skin microorganisms, Staphylococcus epidermidis and Cutibacterium acnes, both commensal bacteria, appear as skin microbiota sentinels. These sentinels have a key role in the skin ecosystem since they protect and prevent microbiota disequilibrium by fighting pathogens and participate in skin homeostasis through the production of beneficial bacterial metabolites. These bacteria adapt to changing skin microenvironments and can shift to being opportunistic pathogens, forming biofilms, and thus are involved in common skin dysbiosis, such as acne or atopic dermatitis. The current evaluation methods for cosmetic active ingredient development are discussed targeting these two sentinels with their assets and limits. After identification of these objectives, research of the active cosmetic ingredients and products that maintain and promote these commensal metabolisms, or reduce their pathogenic forms, are now the new challenges of the skincare industry in correlation with the constant development of adapted evaluation methods.

Antimicrobial activity of liquid residues of Cymbopogon citratus oil extracts

Cymbopogon citratus (Lemongrass) is a type of medicinal herb that widely used in Asia. This study aims to investigate the antimicrobial activity of liquid residues of ethanolic and aqueous Cymbopogon citratus oil extracts. Residues of ethanolic and aqueous Cymbopogon citratus oil extracts were used to study their antimicrobial activities for Staphylococcus aureus; Staphylococcus epidermidis; Pseudomonas aeruginosa and Candida albicans which were isolated from burned skin of patients suffering from burns at Medical City Hospital/Specialist burns Unit/Baghdad. Minimum inhibitory concentration and minimum bactericidal concentration were measured for all microorganisms using microtitre plates and Resazurin dye by a spectrophotometer at 517 nm. The components of liquid residues were detected by phytochemical tests; and the concentrations of Iodine were determined by Ion Chromatography. The antioxidant activity was measured by using DPPH method. The liquid residues of ethanolic and aqueous extracts of Lemongrass showed antimicrobial effect against all the test microorganisms including Pseudomonas aeruginosa. The ethanolic extraction of Cymbopogon citratus contain Alkaloids, Flavonoids, Glycosides, Phenols, Saponins, Terpenes, Tannins, Fatty acids and Couarins, but no Seroids, volatile oil and Emodins. The Minimum Inhibitory Concentrations of ethanolic extract for Staphylococcus aureus; Staphylococcus epidermidis; Pseudomonas aeruginosa and Candida albicans were 12.5, 12.5, 12.5 and 25µl/mL respectively. The extracts of lemongrass residues due to their phytochemical contents and pharmacological activity seem to be highly effective against some pathogenic microorganisms in the inflamed skin. It can be suggested that these extracts may be used for skin treatment in burned patients infected with pathogenic microorganisms.

Nivel de conocimientos de higiene de manos en enfermeras y médicos de tres hospitales nacionales del seguro social de salud, 2018

Introducción: Las manos de los trabajadores de la salud son los más frecuentes medios portadores de los microorganismos responsables de infecciones asociadas a la atención en salud. El objetivo de nuestro estudio fue evaluar el nivel de conocimientos de lavado de manos de tres hospitales nacionales del seguro social de salud en Lima metropolitana, 2018. Material y Métodos: Durante abril-agosto 2018, entrevistamos a enfermeras y médicos de tres hospitales nacionales con un cuestionario administrado en tres secciones y evaluado en escala vigesimal: generalidades, razones de la higiene de manos durante atención en salud y situaciones para realizar la higiene de manos. Resultados: La mediana del nivel de conocimientos de enfermeras y médicos sobre higiene de manos fue de 13,41. El nivel de conocimientos es diferente entre enfermeras y médicos 13,3 vs. 13,6). Asimismo, se encontraron menor frecuencia de acierto en los ítems: desinfección de manos dura 20 a 30 segundos 54,1%, n=276), desinfección de manos tiene 8 pasos 52,9%, n=270), eliminar los microorganismos transitorios de la piel 47,1%, n=240), cuando existe un diagnóstico infeccioso 34,7%, n=177). Conclusión: El nivel de conocimientos de las enfermeras y médicos fue bajo y existe diferencia entre subgrupos profesionales. Se recomienda implementar entrenamientos continuos siguiendo las estrategias multimodulares de la OMS.

Comparison of the Effect of Perineal Care with Normal Saline and 2% Chlorhexidine Solution on the Rate of Catheter-Associated Urinary Tract Infection in Women Hospitalized in Intensive Care Units: A Quasi-Experimental Study

Background: Urinary tract infection is the most common site of infection associated with health care in the Intensive Care Unit (ICU) patients. Long-term catheterization is the most important risk factor for Urinary Tract Infections (UTIs). These infections are more common in women than in men. Colonized microorganisms in the perineal skin and around the urethra may move into the urinary system through the external surfaces of the urinary catheter to cause infection. Objectives: The present study aimed to compare the effect of perineal care with normal saline and 2% chlorhexidine solution on the rate of catheter-associated urinary tract infection (CAUTI) in women hospitalized in ICUs. Methods: A quasi-experimental study was performed on 70 female patients hospitalized in the ICU of Khatam-Al-Anbia Hospital of Zahedan in 2019. The research units meeting the inclusion criteria were selected using convenience sampling and then randomly divided into two groups of normal saline (n = 35) and chlorhexidine (n = 35). The perineal area of patients in the first group was washed with normal saline and the second group with 2% chlorhexidine solutions twice a day for seven days in both groups. To diagnose UTIs, urine samples were cultured on the first and seventh days. Data were analyzed using SPSS 21 via the independent t-test, chi-square test, and Fisher’s exact test at a significance level of less than 0.05. Results: Finally, 60 participants completed the study. The two groups did not differ significantly in terms of age, marital status, level of education, cause of hospitalization, antibiotic use, underlying diseases, fluid intake, and urinary output. At the end of the seventh day after the intervention, the incidence of UTIs was significantly lower in the chlorhexidine group (13.3%) than in the normal saline group (76.7%) (P = 0.001). Conclusions: The results showed that washing the perineal area every 12 hours with 2% chlorhexidine solution compared to normal saline reduces the incidence of CAUTIs in women hospitalized in ICUs. Therefore, perineal care with a 2% chlorhexidine solution is recommended for perineal care of female patients with urinary catheters hospitalized in ICUs.

A novel comprehensive efficacy test for textiles intended for use in the healthcare setting

Soft surfaces, including textiles are found throughout healthcare settings. Pathogens can survive for long periods of time on textiles, and can be transferred to and from the skin. Antimicrobial fabrics are used as an engineering control to prevent infection. Efficacy testing standards have limitations, including single microorganism challenges, multiple fabric plies tested, and lengthy contact times. We developed a novel method that better models in-use conditions through testing standardized mixtures of pathogens and normal skin microorganisms, artificial soils, and a 15-min contact time. Reproducible growth of all microorganisms from frozen stocks was achieved using this method. A novel rechargeable, monitorable N-halamine cotton cellulose fabric, containing 5885 ± 98 ppm of active chlorine, was evaluated with the new method using PBS, artificial sweat, and artificial sweat plus 5% serum as soil. Pathogens tested included Acinetobacter baumannii, Candida albicans, Escherichia coli, vancomycin-resistant Enterococcus faecalis, methicillin-resistant Staphylococcus aureus, methicillin-susceptible Staphylococcus aureus, and Pseudomonas aeruginosa. Each was tested singly and in the presence of a representative normal skin flora mixture, including: Acinetobacter lwoffii, Corynebacterium striatum, Micrococcus luteus, and Staphylococcus epidermidis. When tested singly, all microorganisms were reduced by 3.00 log10 or greater, regardless of artificial soil. In mixture, 4.00 log10 or greater reductions were achieved for all microorganisms. These results suggest that the novel testing method can be used to provide more comprehensive and realistic efficacy information for antimicrobial textiles intended for use in healthcare. Furthermore, the N-halamine fabric demonstrated efficacy against multiple pathogens, singly and in mixtures, regardless of the presence of artificial soils.

Bacteriostatic Effect of Multidose Preservative-free Buffered Saline Used in Scleral Lens Wear.

Scleral lenses have become an increasingly common treatment for ocular surface disease and irregular corneas. Multidose, preservative-free saline solutions are frequently used off-label to fill scleral lenses. Because the fluid resides over the ocular surface during lens wear, contaminated solutions may increase the risk of infectious complications. We sought to assess the viability of skin microorganisms and pathogens associated with keratitis once introduced into a multidose preservative-free saline (MDPFS) solution containing the bacteriostatic agent boric acid (PuriLens Plus; The Lifestyle Co., Inc., Freehold, NJ). Eleven bacterial and one yeast isolate were each inoculated to three lots of MDPFS as well as to sterile normal saline for comparison. Microorganism concentrations were enumerated at baseline and days 1, 3, 7, 14, 21, and 28. Persistence of microorganism viability was compared between MDPFS lots and between MDPFS and normal saline for each organism. Duration of microorganism viability was ≥24 hours in MDPFS with no significant difference in the distribution of survival duration of microorganisms in MDPFS versus normal saline (P = .15). Candida albicans concentrations declined 14 days earlier in MDPFS, whereas concentrations of viable organisms in MDPFS remained within 1 log of baseline for the longest durations for Pseudomonas aeruginosa (7 days), Escherichia coli (14 days), and Achromobacter xylosoxidans (≥28 days). Gram-positive organism concentrations remained within 1 log of baseline for no more than 3 days. Mild lot-to-lot variation in organism concentrations was noted near the end points of viability. Bacteriostasis was demonstrated in that concentrations of all organisms remained at or below baseline levels throughout the 28-day period. After microbial contamination, persistence of organism viability was similar in PuriLens and normal saline. Environmental gram-negative organisms, many of which can contribute to infectious keratitis, can persist for weeks once introduced into saline solutions.

Control of skin microbiota with fatty acids: rethinking the removal of “all” skin microorganisms

Control of skin microbiota with fatty acids: rethinking the removal of “all” skin microorganisms

Nonlinear Radiation in Bioconvective Casson Nanofluid Flow

We investigate the impact of nonlinear thermal radiation and variable transport properties on the two-dimensional flow of an electrically conducting Casson nanofluid containing gyrotactic microorganisms along a moving wedge. In some previous studies, it has been assumed that the fluid viscosity and thermal conductivity are temperature dependent. However, this study assumes that the fluid viscosity, thermal conductivity, and the nanofluid properties, are dependent on the solute concentration. Some experimental studies have shown that the viscosity and thermal conductivity of nanofluids are strongly dependent on the volume fraction of nanoparticles rather than just the temperature. The spectral local linearization method is used to solve the conservation equations. We compare our results with those in the literature, and we discuss the convergence and accuracy of the spectral local linearization method. The impact of some parameters on the skin friction, heat and microorganisms mass transport is discussed.

Deep surgical site infection following thoracolumbar instrumented spinal surgery. Ten years of experience

ObjectiveTo describe the characteristics and evolution of deep surgical site infection following thoracolumbar instrumented spinal surgery (DSITIS) in our centre over a period of ten years. Material and methodDescriptive retrospective study. Patient data (epidemiological/health status), surgical data, infection characteristics/presentation, isolated microorganisms, required surgical debridements, implant removal and major complications linked to infection were evaluated. ResultsWe included 110 patients (80 females). Median follow-up after infection diagnosis was 3.6 years. Adolescent idiopathic scoliosis, adult deformity and degenerative lumbar stenosis were the most frequent aetiologies. Sixty-two percent of the patients had at least one clinical feature that made them prone to infection. Infection presentation was early (0–3 months from first surgery) in 60.4% of the cases, delayed (3–24 months) in 11.7%, and late (more than 24months) in 27%. All patients were treated by surgical debridement. Twenty-five percent needed more than one surgical debridement. Implants were removed in 46% of the patients (71% in the first surgical debridement). The most frequent isolated microorganisms were coagulase-negative Staphylococcus, Propionibacterium acnes and Enterococcus. Major complications appeared in 15% of the patients, and 88% of them required major surgeries. ConclusionsLate DSITIS is more frequent than previously reported. Skin microorganisms predominate among the DSITIS culprits. DSIITS produce a high rate of major complications that usually require major surgery for treatment.

Infección quirúrgica profunda en cirugía instrumentada de raquis toracolumbar. Diez años de experiencia

ObjectiveTo describe the characteristics and evolution of deep surgical site infection following thoracolumbar instrumented spinal surgery (DSITIS) in our centre over a period of ten years. Material and methodDescriptive retrospective study. Patient data (epidemiological/health status), surgical data, infection characteristics/presentation, isolated microorganisms, required surgical debridements, implant removal and major complications linked to infection were evaluated. ResultsWe included 110 patients (80 females). Median follow-up after infection diagnosis was 3.6years. Adolescent idiopathic scoliosis, adult deformity and degenerative lumbar stenosis were the most frequent aetiologies. Sixty-two percent of the patients had at least one clinical feature that made them prone to infection. Infection presentation was early (0-3months from first surgery) in 60.4% of the cases, delayed (3-24months) in 11.7%, and late (more than 24months) in 27%. All patients were treated by surgical debridement. Twenty-five percent needed more than one surgical debridement. Implants were removed in 46% of the patients (71% in the first surgical debridement). The most frequent isolated microorganisms were coagulasa-negative Staphylococcus, Propionibacterium acnes and Enterococcus. Major complications appeared in 15% of the patients, and 88% of them required major surgeries. ConclusionsLate DSITIS is more frequent than previously reported. Skin microorganisms predominate among the DSITIS culprits. DSIITS produce a high rate of major complications that usually require major surgery for treatment.

Infant Feeding Patterns and Eczema in Children in the First 6 Years of Life

To determine if different infant feeding patterns in the first 6 months of life increase the risk of eczema and/or skin allergy in children in the first 6 years of life.The sample population was originally derived from a national consumer opinion panel consisting of 500 000 households from throughout the United States from May 2005 to June 2007. Inclusion criteria included women ≥18 years of age in their third trimester of pregnancy, proficiency in English, a stable address for at least 11 months, a healthy mother and infant at birth, term or near-term birth (>35 weeks’ gestation), singleton birth, an infant weighing at least 5 lb and not in the ICU for >3 days. Exclusion criteria included serious long-term health problems that would affect feeding. Original questionnaires obtained in the Infant Feeding Practices Study II had a sample size of 2907 mother-infant dyads at birth and 1782 at month 12. In 2012, the mothers were recontacted about their child’s well-being at age 6 years. The final sample consisted of 1387 woman-child dyads who provided information on feeding practices in the first 6 months of life and participated in the 6-year follow-up survey.Data were extracted from the Infant Feeding Practices Study II in the United States and its 6-year follow-up. Questionnaires were completed prenatally, near birth, at 1 month, every other month from 2 to 7 months, and then every 7 weeks until age 12 months. Data that were collected included age at onset of eczema, maternal race, family history of eczema, maternal age during pregnancy, parity, maternal prepregnancy BMI, maternal education, marital status, maternal employment, poverty index, household smoking status, sex of infant, birth weight, mode of delivery, and season of delivery. Six different feeding patterns were identified: (1) direct breastfeeding for 1 month; (2) direct breastfeeding for 3 months; (3) direct breastfeeding and pump feeding for the first 3 months; (4) direct breastfeeding, pump feeding, and formula feeding in the first few months; (5) formula feeding for the first 2 to 3 months followed by additional solid food; and (6) formula feeding and solid food since age 1 month. Log-linear models were used to estimate prevalence ratios (PRs) of feeding patterns for infants after doctors diagnosed eczema and/or skin allergy in the first 6 years of life, adjusting for cofounders. Current eczema and/or skin allergy at year 6 of follow-up was used to characterize the disease.Children who received a combination of direct breast milk, pumped breast milk, and formula (pattern 4) had a statistically significant higher PR for eczema and/or skin allergy than children who were directly breastfed for the first 3 months of life (PR: 1.46; 95% confidence interval: 1.01–2.11) in the 6-year evaluation studies. Direct breastfeeding and pump feeding for the first 3 months (pattern 3) also revealed an increased PR; however, it was not statistically significant (PR: 1.26; 95% confidence interval: 0.85–1.89). Formula feeding introduced at birth had no higher risk for the development of eczema.Children who are directly breastfed for the first 3 months of life may have a decreased risk of eczema and/or skin allergy compared with children who drink breast milk both from a bottle and from the breast and are supplemented with formula.Breastfeeding is thought to provide better protection against allergic disease than formula feeding. However, there are several studies with inconclusive or conflicting results. In this study, the authors postulate that the inconsistencies are because the patterns of breastfeeding versus formula feeding are much more diversified. They suggest that pumped breast milk components may be altered in the freezing and reheating process, resulting in a loss of immunoglobulins and a reduction in lipase. The expression of milk may also introduce skin microorganisms into the milk. This large birth cohort study is 1 of few studies in which the trajectory of infant feeding with its relationship to the development of eczema and/or skin allergy in children is managed. These findings reveal the possible benefit of direct breastfeeding in the first 3 months of life in decreasing eczema and skin allergy. Although most pediatricians would argue that “breast is best,” how it is presented and whether it is with or without supplemental formula may affect the immune system in the gut and influence the development of eczema.