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PubMed1982

Pulmonary sclerosing hemangioma: sometimes a form of pulmonary hamartoma.

Previous light and electron microscopic examinations of sclerosing hemangiomas of the lung have raised questions regarding their varying microscopic patterns and cells of origin. We describe two additional cases: one studied by light microscopy revealed the classic pattern of a sclerosing hemangioma of endothelial origin, and a second, studied by combined light and electron microscopy, had incomplete small peripheral airways and occasional alveolar-like spaces derived from epithelial and mesothelial cells. It is concluded that sclerosing hemangiomas of the lung may sometimes consist of admixtures of tissues of epithelial, mesothelial, and endothelial cell origins and thus represent a form of pulmonary hamartoma.

Adult↗
PubMedDate not supplied

Papillary thyroid carcinoma and related thyroid neoplastic lesions: a light microscopic study with emphasis on nuclear changes.

A total of 187 thyroid lesions consisting of 2 cases of Grave's disease, 21 cases of multinodular goiter, 40 follicular adenomas and 124 low-grade papillary thyroid carcinomas were studied to identify intermediate neoplastic lesions in the spectrum of nuclear changes between benign reactive thyroid follicles and low-grade thyroid papillary carcinoma. The lesions were examined and classified on the basis of the following nuclear features: fine chromatin seen in the thyroid papillary carcinomas and coarse chromatin seen in follicular carcinomas. Cases with Hürthle cell changes were excluded from the study. Cases with nuclei containing coarse chromatin were classified in the group of follicular adenomas with a coarse chromatin pattern. The neoplastic thyroid lesions containing fine chromatin showed a spectrum of nuclear changes ranging between reactive follicular lesions and papillary thyroid carcinoma with lymph node metastasis. Such lesions were classified as follicular adenomas with a fine chromatin pattern. The nuclei of these lesions were graded into mild to marked "nuclear atypia with a fine chromatin pattern". The degree of atypia depended on the degree and extent of nuclear changes. Encapsulated follicular adenomas with a fine chromatin pattern and with mild atypia (11 cases), moderate atypia (13 cases), marked atypia (27 cases), and encapsulated or nonencapsulated papillary thyroid carcinoma were characterized by uniform nuclei; with mild, moderate and marked nuclear atypia in less than 2/3 of the cell population and marked nuclear atypia in more than 2/3 of the cell population; and measuring 5.4-6.3, 6.0-7.2, 6.3-9 and 7.2-10 microns in diameter, respectively. Follow-up of cases of papillary thyroid carcinoma fulfilling the above criteria showed lymph node metastasis in 33% of cases, whereas follicular adenomas with a fine chromatin pattern, including cases originally diagnosed as papillary carcinoma, showed no evidence of lymph node or distant metastasis in a follow-up period of 30 months to 15 years. In the thyroid tissue surrounding papillary thyroid carcinoma or encapsulated follicular adenoma with a fine chromatin pattern and marked atypia, adenomatous nodules with a fine chromatin pattern and with low-grade nuclear atypia were identified. The adenomatous nodules with a fine chromatin pattern and with mild, moderate and marked atypia showed architectural, cytoplasmic and nuclear features similar to those of follicular adenoma with a fine chromatin pattern of the same grade. Of interest, a large number of cases of follicular adenoma with a fine chromatin pattern had areas with features of follicular adenoma with a coarse chromatin pattern.

Adenoma↗
PubMed1999

Regional differences in the sympathetic innervation of the guinea pig large intestine by neuropeptide Y- and tyrosine hydroxylase-immunoreactive nerves of divergent extrinsic origin.

Region-specific patterns of nerves with immunoreactivity to neuropeptide Y (NPY) have been described previously in the submucous plexus of guinea pig large intestine. Because these may have functional significance, the possibility of similar, characteristic variations of NPY-like immunoreactivity (NPY-ir) in the myenteric plexus was explored. Regional differences were found in the occurrence and pattern of distribution of NPY-ir in the myenteric plexus of the guinea pig large intestine. NPY-ir was present rarely within neuron somata in any region of the large intestine, and NPY-ir nerve fibers were present only within the distal large intestine, increasing progressively in density from the distal spiral to the rectum. Lesion of the colonic nerves, but not the hypogastric, intermesenteric, or lumbar splanchnic nerves, resulted in a loss of NPY-ir in the distal spiral and transverse colon but not in the descending colon or rectum. Ring myotomies in the descending colon resulted in a loss of NPY-ir proximal to the lesion. Dual-labeling immunohistochemical studies revealed that the NPY-ir nerve fibers rarely contained immunoreactivity for tyrosine hydroxylase (TH). Extrinsic nerve lesions resulted in an unequivocal reduction in NPY-ir in intraganglionic fibers of the submucosal plexuses of the transverse colon and a partial loss in the distal spiral and descending colon: the rectum was unaffected; in only a minority of guinea pigs, however, was any decrease in the NPY-ir innervation of submucosal blood vessels detected. The principal projections of NPY-ir nerves were from and through the inferior mesenteric ganglion; however, NPY-ir was not colocalized with TH-ir. It is proposed that nonnoradrenergic, NPY-containing neurons located in the inferior mesenteric ganglion project through the colonic nerves and that these proximally directed fibers innervate the transverse colon and the distal spiral. Nonnoradrenergic, NPY-ir neurons lying in the pelvic ganglia or sacral sympathetic chain may make an important contribution to the innervation of the myenteric plexus of the rectum and the descending colon.

Animals↗
PubMed1985

Developmental arborization of sensory neurons in the leech Haementeria ghilianii. I. Origin of natural variations in the branching pattern.

The overall sizes, contours, and positions of the receptive fields maintained by different individual cells of the T, P, and N types of mechanosensory neurons in the segmental skin of the leech Haementeria ghilianii are not subject to wide variation. However, the locations and contours of the boundaries which separate the various compartments of the sensory field, namely, the major and minor fields, as well as their component subfields, do vary significantly. These variations are reflected in differences in the detailed pattern of arborization of the mechanosensory axon branches that innervate different parts of the receptive field. The appreciable variation in the kinetics of embryonic outgrowth of sensory axon branches, in conjunction with a mechanism of neuronal self-avoidance, is a probable source of this variability in adult receptive field structure. Thus, establishment of these sensory field components would seem to entail a first-come-first-served territorial exclusion between different axon branches extended by the same neuron.

Animals↗
PubMed2001

Reproductive pattern of the sun bear (Helarctos malayanus) in Sarawak, Malaysia.

Fecal progesterone assays were conducted in 3 captive female sun bears (Helarctos malayanus) segregated from males to characterize the species-specific reproductive pattern in their original distribution area in Sarawak, Malaysia. Peaks of fecal progesterone concentrations were observed once annually, and lactation was observed after increasing progesterone concentrations in all females without mating stimulus. These results suggest that sun bears in Sarawak, Malaysia, may have a seasonal reproductive pattern and ovulation was noted to occur spontaneously, followed by pseudopregnancy.

Animals↗
PubMed2004

Effect of diet composition and feeding pattern on the prececal digestibility of starches from diverse botanical origins measured with the mobile nylon bag technique in horses.

This trial was conducted to determine the extent of prececal starch digestibility depending on the botanical origin of starch and on diet characteristics (i.e., composition and feeding pattern). The prececal disappearance of six substrates (oats, barley, corn, horse bean, potato, and wheat) was measured in four cannulated horses fed (as-fed basis) 11.8 g/kg BW of a high-fiber (HF) or high-starch (HS) pelleted feed and 10.0 g/kg BW of meadow hay using the mobile bag technique (MBT). The daily feeding pattern was either three meals (two meals of pellets and one meal of hay) or five meals (three meals of pellets and two meals of hay). The experimental procedure was a 2 x 2 factorial arrangement tested in a Latin square design. After 2 wk of adaptation to the diet, collections were made on 5 d. Thirty nylon bags, composed of five bags of each substrate, were intubated to each horse during the ingestion of the morning meal. Bags were collected in the cecum, using a magnet, at 9 h postintubation. In spite of strong interindividual differences, approximately 80% of the intubated bags were collected. On average, the mean retention time of the bags was 6.2 h (+/-0.17). Regardless of the feeding pattern, the transit of the bags was faster when the fiber content of the diet was higher (P = 0.003). Likewise, regardless of the meal composition, transit was also faster when the ration was split into five daily meals (P = 0.001). The DM disappearance, corrected with particulate losses (DMD(c)), differed depending on the substrate tested (33.5, 57.1, 63.8, 67.7, 78.6, and 86.2% for potato, horse bean, oats, barley, corn, and wheat, respectively; P = 0.001). The DMD(c) of corn, barley, and potato was higher when HS was fed (P = 0.020); regardless of the substrate, DMD(c) was higher with five daily meals (P = 0.001). The starch disappearance (StarchD(c)) was different depending on the substrate (P = 0.001; 36.1, 71.2, 86.6, 89.2, 99.0, and 99.7% for potato, horse bean, barley, corn, wheat, and oats, respectively). Whatever the substrate, StarchD(c) was higher when HS was fed (P = 0.007), but it was not affected by the feeding pattern of the diet. Although passage rate was modified and feed intake was different, the botanical origin of starch was the main factor that affected prececal starch disappearance in horses.

Animal Feed↗
PubMed1999

Muscle development during vertebrate limb outgrowth.

Limb development has become one of the model systems for studying vertebrate development. One crucial aspect in limb development is the origin, differentiation and patterning of muscle. Much progress has been made in recent years towards understanding this process. One of the general observations is that the genes involved in limb muscle development appear to be very similar to those involved in muscle development in other regions of the embryo. In this review, we summarize some of the genes and mechanisms that regulate limb muscle development and discuss various avenues along which a deeper understanding can be gained of how muscle cells originate and differentiate in different tissues during vertebrate development.

Animals↗
PubMed1993

Alpha-fetoprotein-producing esophageal adenocarcinoma: report of a case.

This paper describes a rare case of adenocarcinoma located in the middle portion of the esophagus with liver metastasis. An 80-year-old man was admitted to our hospital with dysphagia and vomiting, following which an upper gastrointestinal series and esophagoscopy located an elevated-type carcinoma in the middle thoracic esophagus. Computed tomography revealed an esophageal tumor invading the left atrium and aorta, and multiple intrathoracic lymph node swellings, and an ultrasonograph of the liver showed multiple liver metastases. The serum carcinoembryonic antigen, carbohydrate antigen 19-9, and squamous cell carcinoma-related antigen levels were normal, but the serum alpha-fetoprotein (AFP) level was 351.5 ng/ml. The patient died 124 days after undergoing an esophageal bypass operation. On post-mortem histological examination, the original esophageal tumor was diagnosed as a poorly differentiated adenocarcinoma without a squamous component and immunohistochemical staining for AFP showed positive granules in the cytoplasm. All the metastatic nodules, including the lymph nodes, liver, spleen, and lungs, showed the same histological type and AFP-staining pattern as the original esophageal tumor. To our knowledge, this is the first case of AFP-producing esophageal carcinoma to be reported in Japan.

Adenocarcinoma↗
PubMed1995

Like father like son? Sons of patients of European or Indian origin with coronary artery disease reflect their parents' risk factor patterns.

OBJECTIVE: To investigate the extent to which risk factor patterns associated with coronary artery disease (CAD) in patients of Indian origin and in those of North European origin undergoing coronary angiography for suspected angina were reflected in their apparently healthy sons aged 15-30 years. DESIGN: Prospective study in which risk markers were measured in patients of Indian origin and in matched European patients undergoing angiography and in their sons. SETTING: Patients attending a regional cardiac centre and their families. PATIENTS: 102 consecutive male patients of Indian origin undergoing diagnostic coronary angiography for suspected angina and 89 of their sons aged between 15 and 30 years; 102 age matched male European patients and 82 sons. MAIN OUTCOME MEASURES: Father son correlations for risk markers predicting the severity of parental CAD; differences in mean levels of these markers between young males of Indian origin and those of North European origin. RESULTS: Lp(a) lipoprotein, total cholesterol, and serum insulin were independent predictors of the severity of CAD in patients of Indian origin and in those of North European origin. In both groups, there was strong correlation between paternal and filial serum insulin (r = 0.41 Indian origin, r = 0.49 North European, P < 0.001), Lp(a) lipoprotein (r = 0.44 Indian origin, r = 0.48 North European, P < 0.001), and total cholesterol (r = 0.39 Indian origin, r = 0.45 North European, P < 0.001) concentrations, and the risk factor profiles of the sons were predictive of CAD severity in their fathers. Sons of patients of Indian origin had significantly higher serum insulin (Indian origin 14.3 mU/l v North European 8.4 mU/l, P = 0.002) and Lp(a) lipoprotein (Indian origin 19.1 mmol/l v North European 10.5 mmol/l, P = 0.001) concentrations than sons of patients of North European origin. CONCLUSIONS: Apparently healthy young men aged 15-30 years from either ethnic community already reflect risk marker patterns associated with coronary artery disease in their parents, both for genetically determined factors such as Lp(a) lipoprotein and environmentally influenced factors such as insulin and cholesterol. Health promotion measures aimed at reducing the prevalence of CAD should include the adolescent and young adult populations, particularly those with a family history of CAD, or who are from ethnic communities in which this diagnosis is prevalent.

Adolescent↗
PubMed2001

Topographical and physicochemical modification of material surface to enable patterning of living cells.

Precise control of the architecture of multiple cells in culture and in vivo via precise engineering of the material surface properties is described as cell patterning. Substrate patterning by control of the surface physicochemical and topographic features enables selective localization and phenotypic and genotypic control of living cells. In culture, control over spatial and temporal dynamics of cells and heterotypic interactions draws inspiration from in vivo embryogenesis and haptotaxis. Patterned arrays of single or multiple cell types in culture serve as model systems for exploration of cell-cell and cell-matrix interactions. More recently, the patterned arrays and assemblies of tissues have found practical applications in the fields of Biosensors and cell-based assays for Drug Discovery. Although the field of cell patterning has its origins early in this century, an improved understanding of cell-substrate interactions and the use of microfabrication techniques borrowed from the microelectronics industry have enabled significant recent progress. This review presents the important early discoveries and emphasizes results of recent state-of-the-art cell patterning methods. The review concludes by illustrating the growing impact of cell patterning in the areas of bioelectronic devices and cell-based assays for drug discovery.

Animals↗
PubMed2006

Expression of bone morphogenetic proteins in normal human intramembranous and endochondral bones.

Bone morphogenetic proteins (BMPs) are growth and differentiation factors that have been purified and widely accepted to be the most important regulators in the processes of bone formation. The aim of this study was to identify the BMPs that are expressed in normal human bone, and to investigate the specific pattern of BMP2-BMP9 expression in normal human intramembranous and endochondral bone to maintain homeostasis, as well as in ex vivo primary cell culture of human osteoblasts from intramembranous and endochondral bone. Semi-quantitative RT-PCR indicated that 2 types of bone of different embryological origin have distinct patterns of BMP expression. BMP3, 4, 7 and 8 were strongly expressed in normal intramembranous bone compared to endochondral bone, whereas BMP2 and 5 were highly expressed in endochondral bone. The expression of BMP9 and BMP15 in human bone was identified for the first time. From the very similar expression patterns of BMPs in fresh normal bone and ex vivo osteoblastic cell culture, it can be proposed that the different proportions of BMPs in normal human intramembranous and endochondral bone needed to maintain normal homeostasis.

Adult↗
PubMed1991

Polyclonal origin of pancreatic islets in aggregation mouse chimaeras.

In the present study, we have examined the origin and growth pattern of the beta cells in pancreatic islets, to determine whether a single progenitor cell gave rise to all the precursors of the islets, or if each of a few progenitor cells is the founder of a different islet, or if each islet is a mixture of cells originating from a pool of progenitor cells. Aggregation mouse chimaeras where the pancreatic beta cells derived from each embryo can be identified in the islets on histological sections were analyzed. In two chimaeras, all the islets contained cells from both the aggregated embryo. This clearly demonstrates that each islet resulted from several independent cells. In addition, the beta cells derived from either embryo component were in very small clusters in the islets, suggesting that in situ cell division did not account significantly for islet growth.

Animals↗
PubMed2005

Genomic imprinting recapitulated in the human beta-globin locus.

A subset of genes in mammals are subject to genomic imprinting. The mouse H19 gene, for example, is active only when maternally inherited and the neighboring Igf2 gene is paternally expressed. This imprinted expression pattern is regulated by the imprinting control region (ICR) upstream of the H19 gene. A maternally inherited H19 ICR inhibits Igf2 gene activation by the downstream enhancer due to its insulator function while it suppresses H19 gene transcription by promoter DNA methylation when paternally inherited. These parent-of-origin specific functions depend on the allele-specific methylation of the ICR DNA, which is established during gametogenesis. Therefore, the ICR may also function as a landmark for epigenetic modifications. To examine whether the ICR confers these activities autonomously, we introduced a 2.9-kbp ICR-containing DNA fragment into a human beta-globin yeast artificial chromosome at the 3' end of the locus control region and established transgenic mouse lines. Expression of all of the beta-like globin genes was higher when the transgene was paternally inherited. In accord with this result, transgenic ICR DNA from nucleated erythrocytes was more heavily methylated when paternally transmitted. Chromatin immunoprecipitation assays confirmed that CCCTC binding factor is preferentially recruited to the maternal transgenic ICR in vivo. Surprisingly however, the parent-of-origin specific methylation pattern was not observed in germ cell DNA in testis, demonstrating that methylation was established after fertilization. Thus, the ICR autonomously recapitulated imprinting within the normally nonimprinted transgenic beta-globin gene locus, but the temporal establishment of imprinting methylation differs from that at the endogenous Igf2/H19 locus.

Animals↗
PubMed1983

Plasmid pattern analysis of natural bacterial isolates and its epidemiological implication.

Natural isolates of Escherichia coli, Salmonella typhimurium, Klebsiella pneumoniae, and Providencia stuartii were analysed to determine their plasmid content. This data allowed the identification of nosocomial strains of K. pneumoniae and P. stuartii and helped in the differentiation of epidemic strains of E. coli 0111 and S. typhimurium. Phenotypically similar isolates of S. typhimurium could be shown to be of independent origin using plasmid pattern analysis. The dissemination of a particular plasmid through different strains of S. typhimurium resulted in a simulation of a very widely distributed epidemic strain, because the plasmid interfered with the phage type of its host strain in addition to determining resistance properties. Plasmid pattern analysis disclosed two independently existing but interacting epidemic processes: a bacterial 'epidemic' strain may become disseminated over a large territory and may predominate there for a long time; a single plasmid, however, may also become distributed through many different bacterial strains and may spread over a large territory. Plasmid pattern analysis provides a valuable and universal epidemiological laboratory method.

Anti-Bacterial Agents↗