ABSTRACT
BACKGROUND: Phytophotodermatitis (PPD) is a common phototoxic eruption, but very little information is available about its histological aspects, as the diagnosis is clinically established. METHODS: The epilated right half of the back of four albino rats was sprayed with peel juice of Tahiti lemon, one quadrant was exposed to sunlight for 5 min and the other for 8 min. The left back served as control. Biopsies were taken after 1, 2, 3, 4, 5, 6, 24, 48 and 72 h in both sides. RESULTS: The first six time intervals showed a normal epidermis in both sides. After 24 h, the area with peel lemon juice showed keratinocyte necrosis, cytoplasmic vacuolization and spongiosis in all rats, independent of the exposure time. The control side showed isolated keratinocyte necrosis with only 8 min of exposure. After 48 h, erythema is evident and strong vacuolization was observed, which progresses to sub- or intraepidermal blisters. After 72 h, the erythema persisted and histological findings were less intense. CONCLUSIONS: PPD can be successfully reproduced in rat skin. After 24 h spongiosis, vacuolization and keratinocyte necrosis are observed, clinically there are no changes. After 48 h, erythema appears with intra- and subepidermal blistering.
Subject(s)
Citrus/adverse effects , Disease Models, Animal , Fruit/adverse effects , Light/adverse effects , Photosensitivity Disorders/pathology , Animals , Blister/chemically induced , Blister/pathology , Erythema/chemically induced , Erythema/pathology , Humans , Keratinocytes/pathology , Necrosis/chemically induced , Necrosis/pathology , Photosensitivity Disorders/chemically induced , Rats , Time FactorsABSTRACT
The objective of this study was to evaluate the effect of three disaccharides (sucrose, threalose and lactose) used as nonpenetrating cryoprotectants in extender for mice semen. The parameters evaluated were sperm motility (MOT) and cleavage rate (CLV) after in vitro fertilization in the SWISS-ALBINA and BALB/c lines. The treatments were S1=sucrose; S2=threalose; S3=lactose, for SWISS-ALBINA; and B1=lactose; B2=threalose for BALB/c. MOT was evaluated after: thawing (THA), centrifugation and re-suspension in P-1 medium (CEN) and after 10 minutes of incubation (10M). The MOT for the SWISS-ALBINA line was higher for S2 (P
O trabalho objetivou avaliar os efeitos dos dissacarídeos sacarose, trealose e lactose, como crioprotetores impermeáveis à membrana plasmática em diluentes para criopreservação de sêmen de camundongos. Para avaliação do sêmen utilizaram-se os seguintes parâmetros: motilidade progressiva (MOT) das células espermáticas, e a taxa de clivagem embrionária (TXCL) obtida por meio de fertilização in vitro, nas linhagens SWISS-ALBINA e BALB/c. Os tratamentos avaliados foram: S1=sacarose; S2=trealose; S3=lactose, para SWISS-ALBINA e B1=lactose; B2=trealose para BALB/c. Avaliou-se a MOT durante as seguintes etapas: descongelação (DES), centrifugação e ressuspensão no meio P-1 (CEN) e após dez minutos de incubação (10M). A MOT no S2 para a linhagem SWISS-ALBINA nas três etapas (47% no DES; 66,5% na CEN e 67,2% no 10M) foi superior (P
ABSTRACT
The objective of this study was to evaluate the effect of three disaccharides (sucrose, threalose and lactose) used as nonpenetrating cryoprotectants in extender for mice semen. The parameters evaluated were sperm motility (MOT) and cleavage rate (CLV) after in vitro fertilization in the SWISS-ALBINA and BALB/c lines. The treatments were S1=sucrose; S2=threalose; S3=lactose, for SWISS-ALBINA; and B1=lactose; B2=threalose for BALB/c. MOT was evaluated after: thawing (THA), centrifugation and re-suspension in P-1 medium (CEN) and after 10 minutes of incubation (10M). The MOT for the SWISS-ALBINA line was higher for S2 (P
O trabalho objetivou avaliar os efeitos dos dissacarídeos sacarose, trealose e lactose, como crioprotetores impermeáveis à membrana plasmática em diluentes para criopreservação de sêmen de camundongos. Para avaliação do sêmen utilizaram-se os seguintes parâmetros: motilidade progressiva (MOT) das células espermáticas, e a taxa de clivagem embrionária (TXCL) obtida por meio de fertilização in vitro, nas linhagens SWISS-ALBINA e BALB/c. Os tratamentos avaliados foram: S1=sacarose; S2=trealose; S3=lactose, para SWISS-ALBINA e B1=lactose; B2=trealose para BALB/c. Avaliou-se a MOT durante as seguintes etapas: descongelação (DES), centrifugação e ressuspensão no meio P-1 (CEN) e após dez minutos de incubação (10M). A MOT no S2 para a linhagem SWISS-ALBINA nas três etapas (47% no DES; 66,5% na CEN e 67,2% no 10M) foi superior (P
ABSTRACT
The present study was conducted to investigate the effect of topical thiocyanate (SCN(-)) application on hamster cheek pouch mucosa. Sixty-six hamsters were divided into two groups. The test substance containing potassium thiocyanate was applied on the hamsters' cheek pouches at 55 mg/kg dosages. Cheek pouches were grossly examined after 12 weeks. Histometric evaluation included height measurements from the epithelium without stratum corneum, stratum corneum, and full epithelium. Clear cells frequency was compared between groups. Results were analyzed using Student's t test. The experimental group showed a lower height of the stratum corneum (p=0.035) and higher frequency of clear cells (p<0.001). There was no height difference for the epithelium without stratum corneum (p=0.677) and full epithelium (p=0.904) between groups. SCN(-) promotes no gross alterations on hamsters' cheek pouch and does not induce dysplastic features at the epithelium or inflammation at the connective tissue. The ion promotes histologic alterations on mucosa that need to be investigated in further studies.