Near-haploid clones in a malignant fibrous histiocytoma

Near-haploid solid tumors are very rare. In a storiform-pleomorphic malignant fibrous histiocytoma (MFH) of bone, we found three cell populations: one with a near-haploid, a second with a near-diploid, and a third with a near-tetraploid chromosome number. The near-haploid cells had few structural rearrangements: i(12p) and t(13q21q) in one clone, and these two and an additional t(19;?)(p11;?) in another clone. One structurally normal copy of all chromosomes was also present, except that the only chromosome 13 was involved in the t(13q21q). There were also two near-diploid clones, one without the t(19;?) and one with a single copy of this derivative chromosome. This is the first MFH reported to have a near-haploid modal chromosome number, and also the first tumor with i(12p) among bone and soft tissue tumors.     

Differential uptake of systemic fluorochrome Hoechst 33342 in lung and liver metastasis of B16 melanoma

Summary The growth and vascularization patterns of B16 melanoma colonies in the liver and lungs were measured and compared by histological techniques and dye diffusion patterns after injection of the fluorochrome Hoechst 33342. In the liver, the fluorescent pattern of dye diffusion revealed that uninodular tumours measuring up to 146 n in diameter were not functionally vascularized. However, when the nodules fused to give rise to multinodular tumours measuring between 256 and 366 n in diameter, a reticular dye diffusion pattern revealed functional tumour vascularization. In the lungs, subpleural, parenchymal and peritubular (i.e. surrounding blood vessels and airways) tumours were observed. The two former classes were vascularized down to thicknesses and diameters of 49 and 24 m respectively. In contrast, dye diffusion was never seen in peritubular tumour cuffs up to 609 m in thickness. The results indicate differences in vascularization patterns in B16 tumours in the liver and lungs, and differences between tumours growing in different sites within the lungs. If these results are applicable to metastases in these two organs, they indicate potential diffusion-mediated resistance to chemotherapy, and potential hypoxia-mediated resistance to radiotherapy of both metastases and micrometastases.     

Acute systemic heat stress increases glial fibrillary acidic protein immunoreactivity in brain: experimental observations in conscious normotensive young rats.

The possibility that astrocytes participate in the pathophysiology of thermal brain injury caused by systemic heat exposure was examined in conscious young rats. The temporal and regional pattern of the astrocytic response to thermal injury was characterized by demonstrating the immunoreactivity of glial fibrillary acidic protein (GFAP) using monoclonal antibody and avidin-biotin complex technique. Exposure of conscious young animals to heat at 38 degrees C for 4 h in a biological oxygen demand incubator resulted in a marked increase of the GFAP immunoreactivity in specific brain regions as compared with the intact controls. The intensity of the increased GFAP immunoreactivity was mainly noted in pons, medulla and cerebellum, followed by thalamus, hypothalamus, hippocampus and caudate nucleus. The cerebral cortex of heat-exposed animals showed only a mild increase in GFAP immunoreactivity which was predominantly concentrated in cingulate, parietal and pyriform cortices. The immunostaining in general was seen in the perivascular glia, within the neuropil and the glia limitans. This increase in GFAP immunoreactivity was absent in animals exposed to the same ambient temperature (38 degrees C) for 1 h and 2 h, or at a lower temperature (36 degrees C) for 4 h. These results show that (i) astrocytes actively participate in the pathophysiology of heat stress, (ii) endogenous thermal brain injury elicits activation and hypertrophy of astrocytes ("reactive gliosis") depending on the magnitude and duration of the ambient heat stimulus, and (iii) the astrocytic reaction (observed as increased GFAP immunostaining) could be induced much more rapidly within a very short survival period of 4 h, not reported earlier.     

Trisomy 5 and loss of the Y chromosome as the sole cytogenetic anomalies in a cavernous hemangioma/angiosarcoma

Cytogenetic analysis of a cavernous hemangioma with transition to angiosarcoma revealed the mosaic karyotype 47, XY,+5/46, X,-Y,+5/45, X,-Y/46, XY. No cytogenetically analyzed hemangiomas or angiosarcomas have been reported before.     

Lipid and lipoprotein measurements in a normal, adult Cuban population

An attempt was made to determine the normal reference values of lipid- and lipoprotein levels (cholesterol), triglycerides, cholesterol in high- and low-density lipoproteins) in a selected, apparently healthy, Cuban population. Results were expressed as mean, and various percentiles of measured values; two ratios: Risk 1 (LDL-C/HDL-C) and Risk 2 (TC/HDL-C) were also calculated. Approximately 40% of the subjects aged 20 to 30 years had cholesterol values above 200 mg/dl. Females had significantly higher cholesterol HDL-C values than males, whereas the concentrations of LDL-C and LDL were higher in males. Risk 2 ratios were elevated in males. A correlation was shown between lipid levels and age. There was a strong negative correlation between HDL-C and relative body weight. It is suggested that obesity might be an individual risk factor in the population studied.     

Lipid and lipoprotein profiles in Cuban children of three age groups

We determined the lipid and lipoprotein levels in a selected group of apparently healthy adult Cuban subjects in a previous paper /27/. In this paper the basic lipid variables (TC, TG, HDL-C) in 271 healthy children are published. LDL-C levels were also calculated. A small, but continuous, rise was found in the TC level between 0 and 14 years in both sexes. The rise of TG was accompanied by HDL increase in girls but by LDL increase in boys. This phenomenon might explain the augmented susceptibility of men to ischaemic heart disease. Children at "high risk" should be identified (in case of positive family history of ischaemic heart disease) by cholesterol determinations, the borderline of the pathologic cholesterol levels seems to be very similar to that found in the USA, 170-190 mg/dl in the age group between 0 and 14 years.     

Stimulation of mucosal bicarbonate secretion in rat duodenum in vivo by BW755C

Bicarbonate secretion from 12 mm segments of duodenum just distal to the Brunner's gland area was titrated (pH 7.60) in situ in anesthetized rats. Intravenous BW755C (10-20 mg/kg) increased both bicarbonate secretion and the transmucosal electrical potential difference and pretreatment with indomethacin (3 mg/kg intravenously) prevented these effects. Indomethacin also inhibited stimulation of HCO3- secretion by luminal acid (10 mM HCl) but had no effect on the rise in secretion in response to exogenous (luminal) prostaglandin E2. The results support previous suggestions of a role for endogenous prostaglandins in mediation of the HCO3- response to acid and are consistent with the recent demonstration that BW755C increased prostaglandin formation in homogenates of rat intestinal mucosa. Stimulation of HCO3- secretion by BW755C was not enhanced but attenuated by preexposure to luminal acid, suggesting that the latter increases secretion by effects other than mucosal mobilization of arachidonate.     

Structural and replicative forms of mitochondrial DNA in tissues from adult and senescent BALB/c mice and Fischer 344 rats

Age-related changes in the structure and replication of mitochondrial DNA (mtDNA) were investigated in different organs from young adult (9–10 months' old) and senescent (28–29 months' old) BALB/c mice and Fischer 344 rats. Total mtDNA from brain, heart, kidney and liver was isolated by centrifugation in ethidium bromide—CsCl gradient and examined for the occurrence of complex forms and replicative intermediates by electron microscopy. The frequency of catenated mtDNA (interlinked molecules containing two or more circular units) varied from about 2.5% to 5% in adult tissues and showed a small increase in the majority of senescent organs. The frequency of double-sized circular molecules, or circular dimers, was very low in adult tissues, with an average of about 0.04% in mice and 0.1% in rats. The frequency of circular dimers increased with aging to 1.9% in mouse brain and 1.5% in rat kidney, with smaller increases (0.4% and 0.7%) in heart mtDNA from both species; there was no significant increase in the other organs. It is suggested that the increase in the frequency of circular dimer mtDNA reflects an overall deterioration of tissue physiology rather than intrinsic senescent changes in the mitochondria. The frequencies and types of the various replicative forms of mtDNA varied significantly according to tissue but not according to species or donor age. The only exception was a significant increase in the frequency of larger replicative forms in senescent mouse liver, to about 20% compared with 12% in adult liver, suggesting an age-related change in the rate of mtDNA replication and/or turnover in this organ.     

Structural Characteristics and Development of Ampullary Organs in Acipenser naccarii

Ampullary organs of Acipenser naccarii sturgeons were examined by optical and electronic microscopy (transmission electron microscopy and scanning electron microscopy) from hatching until 1 month later when the juvenile phase is completely established. It was observed that, when A. naccarii begins to feed actively, the ultrastructural characteristics of ampullary organs already correspond to those of adult animals. These organs may, therefore, be functional and, together with taste buds, facilitate food search after exhaustion of yolk sac food reserves. Mature ampullary organs of A. naccarii are formed by an ampulla that communicates with the exterior by means of a short channel. These ampullae correspond to the sensory portion of these receptors and are formed by two cell types: receptor cells and support cells. Receptor cells present a kinocilium on their free surface and establish ribbon synapses with axon nerve endings that arise from the underlying conjunctive tissue. Support cells enclose receptor cells, bear stereocilia and occasional cilia, and are of a secretory nature. The mucus associated with ampullary organs mainly comprises neutral mucopolysaccharides, whereas mucopolysaccharides are usually acid in other fish groups. Anat Rec, 290:1178–1189, 2007. © 2007 Wiley‐Liss, Inc.