SciCombinator

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Concept: Acne vulgaris

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Studies have emphasized the importance of disease-associated microorganisms in perturbed communities, however, the protective roles of commensals are largely under recognized and poorly understood. Using acne as a model disease, we investigated the determinants of the overall virulence property of the skin microbiota when disease- and health-associated organisms coexist in the community. By ultra-deep metagenomic shotgun sequencing, we revealed higher relative abundances of propionibacteria and Propionibacterium acnes phage in healthy skin. In acne patients, the microbiome composition at the species level and at P. acnes strain level was more diverse than in healthy individuals, with enriched virulence-associated factors and reduced abundance of metabolic synthesis genes. Based on the abundance profiles of the metagenomic elements, we constructed a quantitative prediction model, which classified the clinical states of the host skin with high accuracy in both our study cohort (85%) and an independent sample set (86%). Our results suggest that the balance between metagenomic elements, not the mere presence of disease-associated strains, shapes the overall virulence property of the skin microbiota. This study provides new insights into the microbial mechanism of acne pathogenesis and suggests probiotic and phage therapies as potential acne treatments to modulate the skin microbiota and to maintain skin health.

Concepts: Medicine, Archaea, Epidemiology, Bacteria, Organism, Microbiology, Acne vulgaris, Propionibacterium acnes

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Various diseases have been linked to the human microbiota, but the underlying molecular mechanisms of the microbiota in disease pathogenesis are often poorly understood. Using acne as a disease model, we aimed to understand the molecular response of the skin microbiota to host metabolite signaling in disease pathogenesis. Metatranscriptomic analysis revealed that the transcriptional profiles of the skin microbiota separated acne patients from healthy individuals. The vitamin B12 biosynthesis pathway in the skin bacterium Propionibacterium acnes was significantly down-regulated in acne patients. We hypothesized that host vitamin B12 modulates the activities of the skin microbiota and contributes to acne pathogenesis. To test this hypothesis, we analyzed the skin microbiota in healthy subjects supplemented with vitamin B12. We found that the supplementation repressed the expression of vitamin B12 biosynthesis genes in P. acnes and altered the transcriptome of the skin microbiota. One of the 10 subjects studied developed acne 1 week after vitamin B12 supplementation. To further understand the molecular mechanism, we revealed that vitamin B12 supplementation in P. acnes cultures promoted the production of porphyrins, which have been shown to induce inflammation in acne. Our findings suggest a new bacterial pathogenesis pathway in acne and provide one molecular explanation for the long-standing clinical observation that vitamin B12 supplementation leads to acne development in a subset of individuals. Our study discovered that vitamin B12, an essential nutrient in humans, modulates the transcriptional activities of skin bacteria, and provided evidence that metabolite-mediated interactions between the host and the skin microbiota play essential roles in disease development.

Concepts: Archaea, Bacteria, Nutrition, Nutrient, Vitamin, Essential nutrient, Acne vulgaris, Propionibacterium acnes

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Epidemiological studies suggest that chocolate increases the incidence and severity of acne. Here we demonstrate that chocolate consumption primes human blood mononuclear cells from volunteers to release more interleukin-1β (IL-1β) and IL-10 upon stimulation with Propionibacterium acne or Staphylcoccus aureus, the two microorganisms involved in the pathogenesis of acne. In contrast, production of the Th17-derived cytokine IL-22 was inhibited by chocolate. Modulation of inflammation could represent an important mechanism through which chocolate consumption influences acne.

Concepts: AIDS, Immune system, Inflammation, Epidemiology, Human, Bacteria, Organism, Acne vulgaris

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Acne vulgaris is a chronic inflammatory disease with a complex pathogenesis that affects predominantly adolescents. The aim of the study was to investigate the interrelations between the presence of acne and several variables associated with somatic growth, pubertal maturation, and environmental conditions (altitude and regions of residence). A population sample of 6,200 clinically healthy boys (0-19 years) was examined and the presence of acne was determined. Height, weight, testicular volumes, penile length and circumference, as well as pubic hair were also measured. The prevalence of moderate and severe acne in the whole group was 7.74 %, while in the age group 12-19 years, it was 19.31 %. Twelve-15-year-old boys with acne were taller and heavier than the ones without. They also had increased penile length and circumference as well as larger testicular volumes. Somatometric and pubertal characteristics of 17-19-year-old boys with and without acne were similar. The prevalence of the disease did not differ between the rural and urban inhabitants. However, the acne frequency decreased with the increasing of the altitude where the boys lived. Conclusions: Our results showed that the development of acne vulgaris in male adolescents was associated with an intensive growth and pubertal maturation, while obesity per se did not play an important role. Of particular interest was the association between the prevalence of acne and the altitude of residence.

Concepts: Inflammation, Puberty, Penis, Acne vulgaris, Height, Length, Sebaceous gland, Pubic hair

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Abstract Background The oral tetracyclines, especially minocycline hydrochloride, are often used as an effective treatment for perioral dermatitis, however they are sometimes difficult to use because of the side effects, especially in children. Objective The effectiveness of β-lactam antibiotics was evaluated in three cases of perioral dermatitis. Methods Three Japanese patients with perioral dermatitis were treated with cefcapene pivoxil hydrochloride hydrate per os 100 to 300 mg per day. They were one girl (age 10) and two adult women (age 32, 37). One of the adult patients had a past history of Meniere’s disease and the other had had a side effect, vertigo, from minocycline hydrochloride treatment. The presence of fusobacteria before and after the treatment was examined using the tape-stripping toluidine blue method. Results These patients showed the improvement in 1 to 2 weeks and were much improved or cured after 2 to 5 weeks. No side effects were found during the treatment. Fusobacteria were positive before treatment but became negative after the treatment in all of them. Conclusion β-lactam antibiotics might be a useful treatment for perioral dermatitis, especially in cases who cannot take tetracyclines.

Concepts: Effect, Effectiveness, Ménière's disease, Adverse effect, Acne vulgaris, Rosacea, Tetracycline antibiotics, Minocycline

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BACKGROUND: The efficacy of fractional erbium-doped yttrium aluminum garnet (Er:YAG) and carbon dioxide (CO(2) ) lasers are well substantiated. OBJECTIVE: To compare the efficacy and safety of these two laser systems for treatment of atrophic scars in dark-skinned patients. MATERIALS AND METHODS: Twenty-four subjects with acne scars were randomly treated with a fractional Er:YAG laser on one side and a fractional CO(2) laser on the other side. All subjects received two treatments with a 2-month interval. Objective and subjective assessments were obtained at baseline and 1, 3, and 6 months after the final treatment. RESULTS: At the 6 month follow up, 55% and 65% of Er: YAG and CO(2) laser sites, respectively, were graded as having more than 50% improvement of scars. Improvement progressed significantly from 1- to 6-month follow-up (p < .001). There was no significant difference in clinical improvement between the two systems at 1- (p = .90), 3- (p = .54), and 6-month (p = .87) follow-up. Reduction in scar volume corresponded to clinical evaluation. CONCLUSIONS: Fractional Er:YAG and CO(2) lasers provided comparable outcomes of scar treatment, but fractional CO(2) laser was associated with greater treatment discomfort.

Concepts: Carbon dioxide, Scar, Acne vulgaris, Erbium, Yttrium aluminium garnet, Garnet, Solid-state laser, Active laser medium

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A proposal has recently been made regarding the potential adjuvant use of platelet-rich plasma (PRP) with fractional carbon dioxide laser (FCL) for the correction of acne scars.

Concepts: Oxygen, Carbon dioxide, Scar, Laser, Carbon dioxide laser, Acne vulgaris, Population inversion, Bell Labs

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The healing of grafted areas after surgical treatment of deep burns frequently generates mutilating scars, and rises the risk of subsequent scar hypertrophy. Scar assessment based on clinical evaluation is inherently subjective, which stimulates search for objective means of evaluation.

Concepts: Scar, Wound healing, Collagen, Healing, Evaluation, Acne vulgaris, FN SCAR

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Abstract Keloids and hypertrophic scars are common lesions, which typically present as a cosmetic concern; however, they also can cause significant pruritus and pain. These lesions pose as a particular therapeutic challenge among clinicians due to a lack of complete knowledge of the formation of keloids and hypertrophic scars. Multiple treatments are widely accepted, yet all have shown limited benefit. In this case, we describe the treatment combination of the Affirm CO2 fractional laser (10,600 nm, Cynosure), Cynergy Pulsed dye laser (585 nm, Cynosure), and triamcinolone acetonide injection for keloids refractory to solitary treatments of triamcinolone acetonide injection and other laser modalities.

Concepts: Scar, Laser, Dye laser, Acne vulgaris, Triamcinolone, Triamcinolone acetonide, Keloid, Pseudofolliculitis barbae

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A simple and especially rapid method, pressurized liquid extraction, has been developed and applied to the quantitative determination of oxytetracycline, tetracycline, chlortetracycline, minocycline, methacycline, demeclocycline and doxycycline in egg, fish and shrimp. The procedure consisted of a trichloracetic acid/methanol extraction conducted at elevated temperature (60°C) and pressure (65bar), without further clean-up, the extraction solution was concentrated and finally for high-performance liquid chromatography analysis. The limits of detection were 5.0-10.0μg/kg and the limits of quantification were 10.0-15.0μg/kg for tetracyclines in egg, fish and shrimp using UV detection. The analytical limits CCα and CCβ were also calculated. The recoveries of tetracyclines spiked at levels of 15-300μg/kg, averaged 75.6-103.5% with the relative standard deviation values less than 11%. The optimized procedure has been successfully applied to real samples in our laboratories. It demonstrated that the new method was robust and useful for monitoring and quantification of 7 tetracycline residues in food of animal origin.

Concepts: Scientific method, Chromatography, High performance liquid chromatography, Standard deviation, Deviation, Acne vulgaris, Rosacea, Tetracycline antibiotics