Mycetoma and phaeohyphomycosis caused by Phialophora parasitica in Thailand.

Phaeohyphomycosis caused by Phialophora parasitica is rare and it has never been documented in Thailand. The first two Thai cases of phaeohyphomycosis caused by P. parasitica were recognized in early 1990 at Ramathibodi Hospital, Bangkok, Thailand. Both patients had underlying diseases. The fungus developed in abscesses with pigmented mycelium at the lower extremity. Cultures from pus and tissue biopsies were positive for dematiaceous fungi. Light microscopic features suggested P. parasitica and which was illustrated by both scanning and transmission electron microscope. The first case was treated with itraconazole with a satisfactory initial response. The second case was successfully treated by surgical removal of the entire lesion.

Parvovirus B19 caused fetal death: a case report in Thailand.

This was a case of an intrauterine parvoviral B19 infection resulting in hydrops fetalis and enlarged placenta. Histologically, the virus was found to be in nucleated red cells of the fetus which was confirmed by electron microscopy. Careful placental examination at the gross and microscopic levels yielded the correct diagnosis.

In vivo and in vitro studies on the morphological change in the monkey epidermal Langerhans cells following exposure to dengue 2 (16681) virus.

A direct comparison of skin Langerhans cell (LC) morphologic change following in vivo and in vitro exposure to dengue-2 (DEN-2) virus (16681) was performed in the monkey to investigate any differences in functional activity profiles. Time-lapse study of skin biopsy at the intradermal (id) virus injection sites, and thin skin sheets removed from the monkey with exposure to virus in culture medium, revealed a highly active migration of epidermal LCs in both sets of experimental specimens. The migration led to a relatively higher number of dendritic cells (DC) which appeared in active migrational profiles, in the superficial dermis. Moreover, obvious cytoplasmic structural changes, corresponding to their immunologic function, were observed in these superficial dermal DCs 2 hours after exposure. Despite their similar changes, early and late endosomes with degraded virus-like particles could be seen in the skin sheets owing to lagging in cellular physiological process in vitro, but none in the skin biopsies. Existence of these endosomes, which was extremely difficult to visualize in vivo, highlighted the mode of antigen processing by the endocytic pathway. The present study showed that the epidermal LC was a potent antigen-presenting cell for eliciting the success of id immunization and carried out the immunological activity in vivo or in vitro in the like manner, in respect to the physiological conditions.

Cytochemical and immunological phenotying of acute nonlymphoblastic leukemia in Thai patients.

Using morphology and cytochemical reaction, we could subclassify-according to FAB classification, 51 of our 56 cases of acute nonlymphoblastic leukemia (ANLL) as M1-M5. Five cases were undifferentiated. Using the immunophenotypic method, we could subclassify 51 of these patients as M1-M4. In addition, 3 cases of undifferentiated leukemia by the prior method were each classified as M1, M3, and myelo-megakaryoblastic leukemia. Correlation of ANLL subtype classification according to each method was not good. However, combination of both methods, using immunophenotypic analysis as a supplement would better subclassify the disease. One of the remaining 2 cases of undifferentiated leukemia was also shown to be myelo-megakaryoblastic leukemia by a positive platelet peroxidase reaction by ultrastructural cytochemistry. Thus, combination of these 3 methods could diagnose and subclassify 55 of the 56 cases (98%) of our ANLL patients.

Ultrastructural characteristics of liver fluke associated human cholangiocarcinoma cell lines.

The ultrastructure of a cholangiocarcinoma cell line (HuCCA-l) originally established from an intrahepatic bile duct tumor of a patient seropositive for a liver fluke infection was studied by scanning (SEM) and transmission (TEM) electron miscroscopy. With the SEM, the surface of HuCCA-1 cells were found to be covered with microvilli. The size of these microvilli varied from cell to cell and they were irregularly distributed. The TEM clearly revealed the presence of cytokeratin filaments, an intracytoplasmic lumen, tight junctions at the apices and desmosomes at the lateral surfaces of neighboring cells, all of which are characteristics of adenocarcinoma cell origin. However, the tumor mass that developed in a nude mouse following subcutaneous injection of these cells was found to exhibit some morphological changes. Specifically, about 20-30% of the tumor cells, particularly those lining the base of the tumor tubules, exhibited electron dense tonofilaments typical of squamous cells. However, this alteration was reversible as the cell line (HuCCA-1Nu) derived from this nude mouse-passage did not exhibit any characteristics reminiscent of squamous cells. These observations are consistent with those occasionally found in human cases reported previously by other investigators. Altogether, the data showed that squamous transformation of adenocarcinoma cells can occur under appropriate conditions. It further showed that reversion to adenocarcinoma cells can occur when the microenvironment is changed.

Effect of aloe vera gel to healing of burn wound a clinical and histologic study.

In a study of twenty-seven patients with partial thickness burn wound, they were treated with aloe vera gel compared with vaseline gauze. It revealed the aloe vera gel treated lesion healed faster than the vaseline gauze area. The average time of healing in the aloe gel area was 11.89 days and 18.19 days for the vaseline gauze treated wound. Statistical analysis by using t-test and the value of P < 0.002 was statistically significant. In histologic study, it showed early epithelialization in the treated aloe vera gel area. Only some minor adverse effects, such as discomfort and pain were encountered in the 27 cases. This study showed the effectiveness of aloe vera gel on a partial thickness burn wound, and it might be beneficial to do further trials on burn wounds.

Establishment and characterization of cell lines from liver fluke-associated cholangiocarcinoma induced in a hamster model.

Cholangiocarcinoma (CCA) is a relatively rare tumor that occurs primarily in tropical countries and particularly in those with a high incidence of liver fluke infection. A hamster model for a liver fluke-associated CCA has been described previously. In the present study, hamster cholangiocarcinoma cell lines were established and characterized in order to obtain information regarding diagnostically useful tumor marker which could shed light for a future investigation for human cholangiocarcinoma. Two related cell lines, one from the original intrahepatic bile duct tumor and one from an allotransplanted tumor, were established. The established cell lines were found to have population doubling times of 31 and 26 hours respectively, and were maintained in Ham's F12 medium supplemented with 10% fetal bovine serum for over 80 passages. The cell monolayers were subjected to scanning and transmission electron microscopic study and found to have ultrastructural characteristics, including cytoplasmic lumens, consistent with those of adenocarcinoma cells of epithelial origin. An immunoperoxidase study using monoclonal antibodies (MAbs) specific for tumor antigens showed the cytoplasm and membrane of both cell lines to be positive. These antigens were also secreted in soluble form into the culture medium, judging from polyacrylamide gel electrophoresis in the presence of SDS and from immunoblot analyses. Different lines of evidence presented suggested that a 200 kDa glycoprotein produced and secreted by the tumor cell lines could be considered a cholangiocarcinoma-associated marker which has diagnostic potential.

Morphological assessment of platelet activation in thalassemia.

Platelets from patients with beta-thalassemia/hemoglobin E, both splenectomized and nonsplenectomized cases, were examined in comparison to those from normal subjects by scanning electron microscopy. In normal subjects, the majority of platelets were discoid (mean +/- SD, 81.0 +/- 3.9%) with 17.3 +/- 3.5% type I spherical shapes (platelet with long axis/short axis greater than 1.1) and 1.3 +/- 1.0% type II (long axis/short axis = 1.0-1.1). The thalassemic patients had significant lower percentage of discoid platelets (60.9 +/- 8.1% in nonsplenectomized patients, 49.2 +/- 9.1% in splenectomized patients) and increase in spherical platelets (nonsplenectomized patients had 36.6 +/- 8.3% type I, 4.0 +/- 1.5% type II; splenectomized patients had 43.4 +/- 7.9% type I, 8.3 +/- 4.5% type II). Study of platelet reversibility from pseudopods to smooth surface showed that thalassemic platelets had poorer reversibility than normal platelets. Splenectomized patients had lower platelet pseudopod reversibility than nonsplenectomized cases. The shape changes and impaired reversibility of platelet pseudopods may be associated with the high tendency of pulmonary thrombus in beta-thal/HbE patients.

Silicosis in ceramic-industry workers with particular reference to the diagnostic value of bronchoalveolar lavage.

We could identify, via bronchoalveolar lavage, crystals in the lavage fluid and in the alveolar macrophages. Thus, BAL could be another method for diagnosing silicosis patients.