Comparative study of phototoxicity of protoporphyrin IX synthetic and extracted from ssp Rattus novergicus albinus rats toward murine melanoma cells.

Protoporphyrin IX (PpIX) is a precursor of heme synthesis and is known to be an active photosensitizer and precursor of photosensitizers applied in photodynamic therapy (PDT) and photodynamic diagnostics (PDD). On irradiation with visible light, PpIX undergoes phototransformation, producing photoproducts which may also be phototoxic and increase its efficacy. The mechanism of PpIX phototransformation depends on environmental characteristics and can be different in vitro and in vivo. In this paper, we present a comparative study of the photoactivity of synthetic PpIX and PpIX extracted from the Harderian gland of ssp Rattus novergicus albinus rats, along with their photoproducts toward murine B16F-10 melanoma cells. It was observed that when irradiated with visible light the endogenous PpIX demonstrates photocytotoxicity ten times higher than the synthetic PpIX. The photoproduct of endogenous PpIX also possesses phototoxicity, though slightly lower than that of PpIX itself. The rate of cell internalization for both endogenous PpIX and its photoproduct was eightfold greater than that obtained for the synthetic porphyrin. This difference might result from a complexation of the native PpIX with some amphiphilic compounds during its synthesis within the Harderian glands, which facilitates the cell uptake of PpIX. Fluorescence microscopy images show that both endogenous and synthetic porphyrins are localized after uptake predominantly in the mitochondrial region of cells.

Relationship between the presence of tonsilloliths and halitosis in patients with chronic caseous tonsillitis.

OBJECTIVE: To study the volatile sulphur compounds (VSC) halitometry profile in a population with chronic caseous tonsillitis (CCT) and halitosis and to evaluate the relationship between the presence of a tonsillolith and abnormal halitometry in this population. DESIGN: Clinical prospective non-randomised study. SUBJECTS AND METHODS: Forty-nine patients with halitosis and CCT, 17 male (35%) and 32 female (65%), were selected among patients referred for CO(2) laser cryptolysis. Anamnesis, physical examination and VSC halitometry were carried out. Halitometry values less than 150 ppb of VSC were considered normal. RESULTS: Patients were divided in two groups: Group A - normal halitometry (41 patients - 83.7%) and Group B - abnormal halitometry (8 patients - 16.3%). Halitometry results in Group B were 5.2 times (429%) higher than in Group A and the majority of the patients with abnormal halitometry presented with a tonsillolith at the moment of examination. A tonsillolith was present in 75% of the patients with abnormal halitometry and only 6% of patients with normal halitometry values. CONCLUSIONS: The presence of a tonsillolith represents a tenfold increased risk of abnormal VSC halitometry and can be considered as a predictable factor for abnormal halitometry in patients with CCT.

Speed of particles ejected from animal skin by CO2 laser pulses, measured by laser Doppler velocimetry.

During ablation of tissue with laser pulses rapid sublimation of matter occurs and high pressures are exerted within the tissue, resulting in steam. smoke and particles being expelled. In this paper we report the speed of particles ejected from animal tissue exposed to CO2 laser pulses measured directly by laser Doppler velocimetry (LDV). Speeds recorded just above animal skin were in the range of 9 to 18 m s(-1) for laser pulses of 128 to 384 J cm(-2) respectively. Aerodynamic turbulence slowed the particles down to a critical speed Vc of 4 m s(-1) within a few millimetres above the laser ablation site. Once the particles reach this minimum speed, if no collisions occur, they will only decelerate by gravitational action and the residual kinetic energy will send the particles up to about 0.87 m from the skin surface. Since ejected particles may carry viable cells, acting as disease vectors during laser surgery, our results suggest that the LDV technique should be used to measure the speed of particles ejected from healthy or pathological human tissues, helping to establish safe conditions during laser surgery.

Uma abordagem psicossomática da rinite alérgica perene / A psychosomatic approach to perennial allergic rhinitis

O presente estudo teve por objetivo investigar os dinamismos psicológicos possivelmente envolvidos na etiologia da renite alérgica perene. Assim sendo, 30 foram estudados através de entrevistas psicológicas e do teste das pirâmides coloridas de pfister. Os dados assim obtidos foram comparados com os da populaçäo de näo-riníticos, representada pela amostra utilizada por Robert Heiss para a padronizaçäo do teste da pirâmide de Pfister. O resultados de ambos os instrumentos de avaliaçäo revelaram que o grupo estudado apresenta dificuldades psíquicas intrínsecas, próprias de falhas no desenvolvimento afetivo-emocional, apontando mais para uma linha neurótica de estruturaçäo da personalidade