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Pieter Becker

Publications and source records attributed to Pieter Becker.

2 recordsLinked to original sources

Maxillary sinus pathology in 119 patients--a histopathologic study.

INTRODUCTION: Information on histopathological changes within sinus mucosa is lacking, both in the general population, and in subjects with specific facial morphology and chronic respiratory obstruction. AIMS AND OBJECTIVES: To provide baseline data of the frequency and nature of pathological changes in the maxillary sinus in a specified group of patients. METHODS: 119 patients undergoing elective maxillary osteotomies were selected. These included patients with (70) and without (49) vertical maxillary excess (VME), and mouth and nasal breathers. The frequency and nature of the histopathological changes within the maxillary antral lining were recorded. RESULTS: Patients ranged from 13 to 47 years, with a M:F ratio of 1:2.4. The findings included congestion (95%), submucosal oedema (90%), retention cysts (26%), true polyps (4.6%) and inflammation. There was eosinophilia (68%), basement membrane thickening (28%), goblet cell hyperplasia (95%) and dystrophic calcification (59%). CONCLUSIONS: A significant degree of sinus pathology was found in this specified group of patients. This was probably due to their living in a polluted urban environment. In the presence of such widespread pathological changes and the virtual impossibility of obtaining "normal" control tissue, investigators may find it impossible to correlate maxillary sinus pathology with either facial form or breathing pattern.

Adolescent↗

Nitric oxide metabolites in naturally occurring canine babesiosis.

Babesiosis, caused by the virulent haemoprotozoan parasite Babesia canis rossi, is an important disease of dogs in South Africa. The nitric oxide metabolites, nitrate and nitrite (collectively termed reactive nitrogen intermediates or RNIs) were measured in admission sera from dogs in a babesiosis-endemic area. Five groups were prospectively studied: mild uncomplicated (n=9), severe uncomplicated (severe anaemia) (n=10) and complicated babesiosis (n=11); and two groups of healthy aparasitaemic dogs: endemic controls from the study area (n=10) and experimental dogs kept in tick-free conditions (n=10). Four measures of RNI production were studied: (i) serum RNI; (ii) serum RNI/creatinine ratio; (iii) fractional clearance of RNI (FC(RNI)); (iv) fractional excretion of RNI (FE(RNI)). Marked elevations of serum RNI occurred in only two dogs, both in the severe uncomplicated group. The highest concentration (log value 5.29 micromol/l) was in a dog that died, but concentrations in the other four dogs that died were unremarkable (0, 0.34, 1.66 and 2.64 micromol/l). Age, appetite and free serum haemoglobin were significant covariates for measures of RNI production. There were no significant differences among the babesiosis groups for serum RNI. Adjustment for creatinine had minor effects on the results. All babesiosis groups had significantly higher serum RNI and RNI/creatinine than the tick-free control group, but did not differ from the endemic controls except for the severe uncomplicated group, which had higher RNI/creatinine. The complicated group had significantly lower FC(RNI) and FE(RNI) than all other groups, except for the tick-free control group, which had similar FE(RNI). The results indicate that, in an endemic area, measures of RNI production are unlikely to be useful indicators of severity or outcome in canine babesiosis.

Animals↗