Measurement of regional rates of cerebral protein synthesis with L-[1-11C]leucine and PET with correction for recycling of tissue amino acids: II. Validation in rhesus monkeys.

The confounding effect of recycling of amino acids derived from tissue protein breakdown into the precursor pool for protein synthesis has been an obstacle to adapting in vivo methods for determination of regional rates of cerebral protein synthesis (rCPS) to positron emission tomography (PET). We used a kinetic modeling approach to estimate lambda, the fraction of the precursor pool for protein synthesis derived from arterial plasma, and to measure rCPS in three anesthetized adult monkeys dynamically scanned after a bolus injection of L-[1-11C]leucine. In the same animals, lambda was directly measured in a steady-state terminal experiment, and values showed excellent agreement with those estimated in the PET studies. In three additional monkeys rCPS was determined with the quantitative autoradiographic L-[1-14C]leucine method. In whole brain and cerebellum, rates of protein synthesis determined with the autoradiographic method were in excellent agreement with those determined with PET, and regional values were in good agreement when differences in spatial resolution of the two methods were taken into account. Low intrasubject variability was found on repeated PET studies. Our results in anesthetized monkey indicate that, by using a kinetic modeling approach to correct for recycling of tissue amino acids, quantitatively accurate and reproducible measurement of rCPS is possible with L-[1-11C]leucine and PET.     

Febrile interstitial pneumonia in a HIV positive patient. Diagnosis by transbronchial biopsy after non-contributory bronchoalveolar lavage]

The authors report a case of HIV infection revealed by pneumocystosis. Bronchoalveolar lavage failed to provide a diagnosis. A second bronchial fibroscopy associated with transbronchial biopsies enabled the diagnosis of invasive pneumocystosis to be made.     

Metastatic appendiceal adenocarcinoma presenting late as epididymo-orchitis: a case report and review of literature

Background  

Whereas testicular metastases are in themselves a rare entity, testicular secondaries from an appendiceal carcinoma have not yet been described. The case also illustrates the diagnostic dilemma of a tumour presenting as epididymo-orchitis.     

Acquired gluteal myospherulosis secondary to intramuscular injections of petrolatum-based hormones: a case report diagnosed by fine-needle aspiration cytology

A case of acquired myospherulosis of the right gluteal region diagnosed by FNA cytology is reported in a woman who had received a series of intramuscular injections of petrolatum-based hormones. The lesion is characterized by inflammatory pseudocystic nodules containing saccular formations with erythrocytes or "bags of marbles." It results from a physical process similar to the emulsion phenomenon between nonresorbent oily material and plasma. This process gives rise to sequestration of blood corpuscles by oily materials and thus development of foreign body granulomas.     

Clinical experience with a single field rotational total skin electron irradiation technique for cutaneous T-cell lymphoma.

Between October 1981 and December 1989, 44 patients with cutaneous T-cell lymphoma (CTCL) were treated with a single field rotational total skin electron irradiation (RTSEI) technique developed in the McGill University, Department of Radiation Oncology. Only 11 (25%) of the 44 patients had received no prior treatment. Three-quarters (33/44) had advanced (T3 or T4) disease. Complete responses were seen in 32/44 (73%) of patients (91% T2, 71% T3 and 58% T4), but only 3/11 (27%) of patients with T2 disease and 3/21 (14%) of patients with T3 disease remain in continuous complete remission in the skin, after median intervals of 58 and 35 months, respectively. Median cause-specific survival for the whole group is 43 months and survival at 5 years is 38%. Survival was significantly better for patients with T2 disease than for patients with T3 disease (relative risk 4.3; 95% CI 1.4-13.2) and patients with T4 disease (relative risk 3.1; 95% CI 0.8-12.1). The RTSEI technique used at McGill has depth-dose characteristics and photon contamination similar to other commonly used TSEI techniques. It is relatively simple and provides a homogenous dose distribution over the entire skin surface in a short treatment time. Results of treatment are similar to those obtained with other techniques. For T2 disease, TSEI is an effective treatment modality with a possibility of long-term tumor control. For more advanced disease, more aggressive treatment, which may include TSEI, is necessary.     

An advantage for detecting dynamic targets in natural scenes

In the present study, we tested the extent to which observers use dynamic information to detect targets in natural scenes. For this purpose, we used composite stimuli in which target sequences were superimposed onto distractor sequences. We varied target visibility in the composite sequence, and the presence or absence of motion. Across four experiments, we found a dynamic advantage for target detection: Observers performed more accurately with dynamic than static target scenes. This advantage depended on the availability of target motion, irrespective of whether the target was upright or inverted in the image plane (Experiments 1-4). The magnitude of this advantage also depended on the availability of segmentation cues (Experiments 1 and 2) and on the distractors used (Experiments 2 and 4). Overall, the dynamic advantage reported extends previous work using isolated dynamic objects to more complex scenes.     

Renin localization in segmental renal hypoplasia

Summary The distribuation of renin in two cases of segmental renal hypoplasia was investigated by immunofluorescence and the peroxidase anti-peroxidase (PAP) method using an anti-human renin antiserum. Renin-containing cells were found only in hypoplasic segments in the vicinity of altered glomeruli and small arteries. Well-preserved renal cortex and areas of chronic atrophic pyelonephritis failed to show any demonstrable site of renin production.Whatever is the mechanism of the disease, the characterization of large numbers of renin-containing cells in the affected kidney support a role for the renin-angiotensin system stimulation in this form of hypertension.