Experimental Infections with Group A Streptococci in Humans

Experimental inoculation of 7 strains of Group A streptococci failed to result in either colonization or infection of normal intact skin of human volunteers. All strains rapidly died on normal skin; suppression of the resident microflora did not affect survival and no difference in survival was seen between inoculation on lipid-rich and lipid-poor body areas. Inoculation on skin damaged by superficial scarification resulted in localized infections when 1 × 104 or more organisms were inoculated into the wound by rubbing and covered with an impermeable plastic film. Intradermal inoculation resulted in localized cellulitis, regional lymphadenopathy, and fever. All strains were equally effective in producing localized infections in scarified skin

The Influence of UVA and Visible Radiation on Acute Damage by Short-Wave UVR (λ < 320 nm)

The influence of UVA and visible radiation on the acute damage by short-wave ultraviolet radiation (UVR) (λ < 320 nm) was investigated in human volunteers, using delayed erythema and sunburn cell production as markers of injury. It was found that subsequent exposure to UVA + visible radiation produced a significant reduction of the threshold erythema dose by short-wave UVR, in a dose-dependent manner. Subsequent exposures to varying doses of UVA + visible radiation, as well as to visible light alone failed to influence sunburn cell production. It is concluded that there is a positive interaction between short-wave UVR and UVA in the induction of delayed erythema, but this may not apply to epidermal cell injury. Photorecovery was not observed

Comprehension following silent and oral reading in grades two and three

Thesis (Ed.M.)--Boston Universit

Comprehension following silent and oral reading in grades two and three

Thesis (Ed.M.)--Boston Universit

Quantitative Microbiology of the Scalp in Non-Dandruff, Dandruff, and Seborrheic Dermatitis

The composition of the scalp microflora was assessed quantitatively in normal individuals and in patients with dandruff and seborrheic dermatitis, disorders characterized by increasing scalin. Three organisms were constantly found: (1) Pityrosporum, (2) aerobic cocci, and (3) Corynebacterium acnes. Pitrosporum (mainly Pityrosporum ovale) made up 46% of the total microflora in normals, 74% in dandruff, and 83% in seborrheic dermatitis. The geometric mean number of organisms per cm2 in non-dandruff subjects was 5.04 × 105; 9.22 × 105 in dandruff subjects; and 6.45 × 105 in those with seborrheic dermatitis. The cocci were dominantly Baird-Parkertype SII and no quantitative or qualitative change occurred in the scaling disorders. C. acnes comprised 26% of the flora on the normal scalp, 6% in dandruff, and only 1% in seborrheic dermatitis. These results differ significantly from previous reports which describe a much more complex microflora and suggest an etiologic role for microorganisms in dandruff

High-Definition Optical Coherence Tomography for the in vivo Detection of Demodex Mites

Background: Demodex mites are involved in different skin diseases and are commonly detected by skin scrape tests or superficial biopsies. A new high-definition optical coherence tomography (HD-OCT) with high lateral and axial resolution in a horizontal (en-face) and vertical (slice) imaging mode might offer the possibility of noninvasive and fast in vivo examination of demodex mites. Methods: Twenty patients with demodex-related skin diseases and 20 age- and gender-matched healthy controls were examined by HD-OCT. Mites per follicle and follicles per field of view were counted and compared to skin scrape tests. Results: HD-OCT images depicted mites in the en-face mode as bright round dots in groups of 3-5 mites per hair follicle. In the patients with demodex-related disease, a mean number of 3.4 mites per follicle were detected with a mean number of 2.9 infested follicles per area of view compared to a mean of 0.6 mites in 0.4 infested follicles in the controls. The skin scrape tests were negative in 21% of the patients. Conclusion: The innovative HD-OCT enables fast and noninvasive in vivo recognition of demodex mites and might become a useful tool in the diagnosis and treatment monitoring of demodex-related skin diseases. Copyright (C) 2012 S. Karger AG, Base