Microsc Microanal
September 2000
Magnetotactic bacteria from aquatic environments were analyzed with the electron spectroscopic imaging technique. Rod-shaped bacteria and cocci were present in most of the samples observed. Magnetotactic multicellular aggregates were also observed at some of the sampling sites.
View Article and Find Full Text PDFNephrol Dial Transplant
September 2000
Background: Anaemia is one of the major clinical characteristics of patients with chronic renal failure, and has a considerable effect on morbidity and mortality. Adequate dialysis is of paramount importance in correcting anaemia by removing small and medium-sized molecules, which may inhibit erythropoiesis. However, high-molecular-weight inhibitors cleared only by means of highly porous membranes have also been found in uraemic serum and it has been claimed from uncontrolled studies that high-flux dialysis could improve anaemia in haemodialysis patients.
View Article and Find Full Text PDFA unique feature of the vertebrate gravity receptor organs, the saccule and utricle, is the mass of biomineral structures, the otoconia, overlying a gelatinous matrix also called "otoconial membrane" on the surface of the sensory epithelium. In mammals, otoconia are deposits of calcium carbonate in the form of composite calcite crystals. We used quick-freezing, deep etching to examine the otoconial mass of the guinea pig utricle.
View Article and Find Full Text PDFProstaglandins Leukot Essent Fatty Acids
April 2000
This study aims to examine the possible relationship between cytokines, nitric oxide (NO) and prostaglandins in the pregnant rat uterus. Results indicate that 1) IL1alpha enhances the synthesis of prostaglandins and augments NO production in pregnant rat uteri and 2) the effect of IL1alpha on prostaglandin synthesis is abolished by NMMA, a NOS inhibitor, by aminoguanidine, an iNOS inhibitor, and by NS-398, a COX-2 inhibitor. These results suggest that there is an interaction between IL1alpha, NO and prostaglandins and that are involved COX-2 and iNOS in this interrelationship.
View Article and Find Full Text PDFProstaglandins Leukot Essent Fatty Acids
April 2000
We have studied the effect of nitric oxide (NO) on the production of arachidonic acid ([14C]-AA) metabolites in the rat oviduct. The basal synthesis of eicosanoids was measured by the conversion of ([14C]-AA) to the different radiolabeled products of cyclooxygenase (COX). The oviducts incubated for 1 h with the labeled substrate of COX were able to convert 3.
View Article and Find Full Text PDFBackground/aim: The aim of this study is to improve the obstetrician-based cord blood collection system and an efficient recovery of CD34+ haematopoietic progenitor stem cells.
Methods: CD34+ cells were purified from total blood using a positive selection enrichment method, called Mini-Macs.
Results: The final yield of CD34+ cells we obtained was 10(4) cells/ml, with a CD34+ purity of 99%.
Interleukin-12 (IL-12) is a major immunomodulatory cytokine that represents a functional bridge between the early resistance and the subsequent antigen specific adaptive immunity. TNF-alpha and IFN-gamma have an important role in the generation of hsp65 specific cytotoxic T lymphocytes (CTL) that lyse hsp65-pulsed autologous macrophages (hsp65 CTL). Since a positive feedback mechanism between TNF-alpha, IFN-gamma and IL-12 has been described, we undertook to evaluate the role of IL-12 on the hsp65 CTL generation in leprosy patients.
View Article and Find Full Text PDFProstaglandins Leukot Essent Fatty Acids
December 1999
We examined the possible relationship between cytokines, nitric oxide and prostaglandins (PGs) in the estrogenized rat uterus. Results indicate that epidermal growth factor (EGF) enhances the synthesis of prostaglandins in estrogenized rat uteri and induces the augmentation of nitric oxide (NO) production in this tissue by stimulating iNOS. While the effect of EGF is abolished by L-NMMA, an NO antagonist, the NS-398, a cyclooxygenase-II (COX-II) inhibitor, prevents the augmentation of prostanoids induced by EGF.
View Article and Find Full Text PDFBraz J Med Biol Res
February 2000
Amorphous phosphate granules are present in vertebrate and invertebrate organisms. The functions attributed to these structures depend on their mineral contents and organic matrix composition. In the present study we have determined zinc concentrations in the hepatopancreas of the crab Ucides cordatus from regions contaminated with zinc, and the elemental composition of hepatopancreal phosphate granules.
View Article and Find Full Text PDFExtraocular sebaceous carcinoma is an uncommon neoplasm usually localized on the head and neck. Sebaceous glands are abundant on the vulva, but vulvar sebaceous carcinoma is an uncommon neoplasm. To our knowledge, there are only five previously reported cases of sebaceous carcinoma on this location.
View Article and Find Full Text PDFWe report a typical case of papular-purpuric "gloves and socks" syndrome (PPGSS) in which primary infection by parvovirus B19 was demonstrated by seroconversion to this virus; parvovirus B19 DNA was also identified by polymerase chain reaction (PCR) methods in the sera of the patient and in the cutaneous biopsy specimen, both taken 4 days after the onset of clinical manifestations. To our knowledge, this is the fourth published case in which parvovirus B19 DNA has been recovered from the skin by PCR. Serologic studies and PCR investigations in cutaneous biopsy for other viruses including herpes simplex virus types 1 and 2, varicella zoster virus, Epstein-Barr virus, cytomegalovirus, and human herpesvirus 6, 7, and 8 were negative.
View Article and Find Full Text PDFNephrol Dial Transplant
October 1999
Background: The regulation of PTH secretion by calcium is altered in patients with primary hyperparathyroidism (HPT). A similar abnormality may occur in secondary HPT, but comparisons of PTH secretion in normal subjects and those with secondary HPT have given contrasting results. Differences in baseline serum ionized calcium (ICa) may partly account for these conflicting results.
View Article and Find Full Text PDFBackground: Infundibulocystic basal cell carcinoma is a recently described distinctive clinicopathologic variant of basal cell carcinoma. Histopathologic differential diagnosis among infundibulocystic basal cell carcinoma, trichoepithelioma, and basaloid follicular hamartoma has generated controversy in the literature.
Observations: Members of 2 families with multiple infundibulocystic basal cell carcinomas are described.
Eighty nephrotic adults with focal segmental glomerulosclerosis (FSGS) and plasma creatinine lower than 3 mg/dL were given corticosteroids (53 patients) or immunosuppressive agents (27 patients) for a median of 16 and 75 weeks, respectively. Forty-two patients responded with complete remission (29 patients, 36%) or partial remission (13 patients, 16%). Twenty-six patients who did not respond were treated again.
View Article and Find Full Text PDFWe report on the presence of magnetic iron oxides in the migratory ant Pachycondyla marginata. Magnetic particles were extracted from different parts of the ant (head, thorax and abdomen) using magnetic precipitation methods. Electron spectroscopic images for iron and oxygen were obtained from the extracted particles, and, by using the corresponding electron micrographs, histograms of size distribution were constructed.
View Article and Find Full Text PDFSince bone mineral density may be influenced by the polymorphisms of the vitamin D receptor (VDR) gene, we studied whether VDR genotypes might drive the progression toward hyperparathyroidism or hypoparathyroidism in patients with end-stage renal disease. On the basis of their parathyroid hormone (PTH) levels, we divided 99 patients undergoing dialysis into 2 groups: 56 patients with hypoparathyroidism (PTH < 104 pg/mL [< 11 pmol/L]) and 43 with hyperparathyroidism (PTH > 261 pg/mL [> 27.5 pmol/L]).
View Article and Find Full Text PDFEur J Gynaecol Oncol
November 1999
One hundred and twelve women with endometrial carcinoma were studied with serum sampling to determine preoperative and postoperative levels of CEA, CA 15-3, CA 19-9, TPA and CA 125. After surgical treatment 88 patients had stage I, 8 stage II, 14 stage III and 2 stage IV disease. Before treatment the sensitivity of CEA, CA 15-3, CA 19-9, TPA and CA 125 was 22.
View Article and Find Full Text PDFWe used energy-filtering transmission electron microscopy to image magnetite crystals isolated from uncultured magnetotactic bacteria. These magnetite crystals were shadowed in high vacuum with platinum at 45 degrees. The shadowed crystals were observed in a Zeiss (Thornwood, NY) CEM902 transmission electron microscope.
View Article and Find Full Text PDFWe present the case of a 57-year-old woman with a 1-year history of a cutaneous eruption clinically and histopathologically characteristic of Degos disease. In one of the two cutaneous biopsy specimens taken from the trunk lesions, the histopathology consisted of necrosis and sclerosis of the subcutaneous lobules, a finding that to our knowledge has not been previously described in the cutaneous lesions of Degos disease. Two months after cutaneous biopsies were taken, the patient developed ptosis and an episode of acute abdominal pain; intestinal perforation and many characteristic lesions of visceral Degos disease involving the entire small bowel were noted at laparotomy.
View Article and Find Full Text PDFThe saccule and the utricle of the vestibular system detect linear acceleration and gravity. Sensory transduction in these organs depends on myriads of calcium carbonate crystals of high specific gravity, called otoconia, embedded in a filament matrix that overlies the sensory epithelium. The coexistence of hard crystals and slender filaments in this complex extracellular matrix makes it difficult to analyze by conventional electron microscopy.
View Article and Find Full Text PDFReactive angioendotheliomatosis is a rare benign process that has been mainly described in patients with systemic infections, such as subacute bacterial endocarditis or tuberculosis, and in association with intravascular deposition of cryoproteins. Histopathologically, it is characterized by a proliferation of endothelial cells within vascular lumina resulting in the obliteration of the involved vessels. Another rare variant of reactive angioendotheliomatosis has been described in the lower extremities of patients with severe peripheral vascular atherosclerotic disease.
View Article and Find Full Text PDFCanary Islands wrestling is a variant of the sport played exclusively in that region, and is associated with close participant contact. An outbreak of a fungal infection, so-called tinea gladiatorum, amongst such wrestlers in Lanzarote, one island in the archipelago is now described. 102 wrestlers from the eight teams on the island were examined; some of the clubs are 50 km apart; 45 wrestlers (44.
View Article and Find Full Text PDFClin Exp Dermatol
September 1998
Cutaneous infections by nontuberculous mycobacteria (NTM) are not usual but their relative importance has changed during the last few years and still further changes are expected. This study comprised 13 patients from whom NTM were recovered from skin biopsy specimens, sinus exudates or cutaneous abscesses. All samples were processed according to standard methods, and the isolates were identified by biochemical testing.
View Article and Find Full Text PDFAtomic force microscopy (AFM) was used to study tooth surfaces in order to compare the pattern of particle distribution in the outermost layer of the tooth surfaces. Human teeth and teeth from a rodent (Golden hamster), from a fish (piranha), and from a grazing mollusk (chiton) with distinct feeding habits were analyzed in terms of particle arrangement, packing, and size distribution. Scanning electron microscopy and transmission electron microscopy were used for comparison.
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