Acetylcholine and A23187, two acetylcholinergic agonists, were used to induce the stimulus-secretion coupling of the isolated rat adrenal medulla cells. Morphometry of numerical density and electron probe X-ray quantitative microanalysis were adopted to measure the alterations in the number and calcium content of chromaffin granules in adrenal medulla cells during the agonist treatment. Secretion of epinephrine was detected by the high performance liquid chromatography (HPLC). It was found that the Ca content of the isolated rat adrenal medulla chromaffin granules dropped significantly after a 10-min incubation with the agonists, whereas the number of chromaffin granule decreased slowly during the agonist treatment and the epinephrine concentration raised significantly after a 20-min incubation with the agonists. The decrease of granule Ca content occurred earlier than the increase of epinephrine concentration, suggesting that the calcium released from chromaffin granule may in part account for the induced cell secretion.

OBJECTIVETo investigate diagnostic histopathology and ultrastructure features of primary pulmonary cryptococcosis (PC).

METHODSClinical data and pathologic findings of 27 cases of PC were retrospectively reviewed, light and electron microscopic evaluations and histochemistry stain studies were performed.

RESULTSThe specimens consisted of 2 fine-needle aspiration lung biopsies and 25 cases of open lung biopsies. Cryptococcosis granuloma formation was identifiable by histopathological examination in 25 of 27 cases, with gum-like lesion and fungi in the remaining 2 cases. The detection rates of cryptococcus neoformans (CN) by mucicarmine (MC), periodic acid-Schiff (PAS), alcian blue (AB) and Grocott methenamine-silver (GMS) were 87.0% (20/23), 100% (27/27), 66.7% (18/27), and 100% (23/23) respectively. Under the electron microscope, most CN had a simple structure with a few organelles. The capsule was seen in all organisms. A percentage of the organisms showed nuclei, nucleoli, mitochondria and vacuoles. The detection rate of CN by EM was 91.7% (11/12).

CONCLUSIONSThe clinical manifestation and imaging of PC are nonspecific for PC. Lung biopsy is the major diagnostic modality. The detection rate by electron microscopy was quite high. Therefore, a correct diagnosis of pulmonary cyrptococcosis should rely on the combination of histopathological evaluation, histochemistry staining and/or electron microscopic examination.

Adult ; Aged ; Biopsy, Fine-Needle ; Cryptococcosis ; microbiology ; pathology ; Cryptococcus neoformans ; isolation & purification ; ultrastructure ; Diagnosis, Differential ; Female ; Follow-Up Studies ; Humans ; Lung ; pathology ; ultrastructure ; Lung Diseases, Fungal ; classification ; microbiology ; pathology ; Male ; Microscopy, Electron ; Middle Aged ; Retrospective Studies

OBJECTIVETo study the distribution of genomovars and microevolution of Yersinia pestis in the Qinghai-Tibet Plateau.

METHODSPrimer pairs targeting the twenty-two different regions(DFRs) were designed for detecting the presence or deletion of each DFR in 297 strains isolated from the Qinghai-Tibet Plateau.

RESULTS9 genomovars, i. e. Genomovar 1, 5, 6, 7, 8, 10, 11, new type and Ype-ancestor were identified in the Marmota himalayana plague focus of the Qinghai-Tibet Plateau. Among these genomovars, genomovar 5,8 and 10 were dominant types. The total rate of the three genomovars was 80.6% (204/253) and the genomovars in different regions were different. All of 44 strains of Y. pestis in the Microtus fuscus plague focus of the Qinghai-Tibet Plateau belonged to genomovar 14.

CONCLUSIONThe distribution of genomovars of Y. pestis in the Qinghai-Tibet plateau had remarkable characteristics geographically. Based on the distribution of genomovars of Y. pestis, the routes of transmission and microevolution of Y. pestis were proposed.

Biological Evolution ; China ; Geography ; Humans ; Plague ; transmission ; Yersinia pestis ; genetics