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11.
Role of Periductal and Ductular Epithelial Cells of the Adult Rat Pancreas in Pancreatic Hepatocyte Lineage: A Change in the Differentiation Commitment 总被引:4,自引:8,他引:4
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M. Sambasiva Rao Rama S. Dwivedi Anjana V. Yeldandi V. Subbarao Xiaodi Tan Mohammed I. Usman Shobha Thangada Mohan R. Nemali Sujata Kumar Dante G. Scarpelli Janardan K. Reddy 《The American journal of pathology》1989,134(5):1069-1086
Development of pancreatic hepatocytes in adult rats maintained on copper deficient diet containing 0.6% trien (CuDT) has been reported recently. To elucidate the histogenesis of hepatocytes a sequential study was undertaken using morphologic, histochemical, immunochemical, in situ hybridization, and Northern blot analysis. Male F-344 rats weighing 80 to 90 g were fed CuDT for 8 weeks and returned to normal rat chow. Beginning from 4 weeks of copper depletion, there was a progressive loss of acinar cells and by 8 weeks more than 90% of the acinar tissue was lost. During this period, there was an increase in the number of adipocytes in the interstitium, and in the number of interstitial and ductular cells. Morphologic observations were confirmed by immunoblot and Northern blot analysis, in which the amount of pancreatic proteins and their mRNAs decreased between 5 and 8 weeks. During this period, a progressive increase in the level of albumin mRNA was observed. In situ hybridization, performed at 7 weeks of copper deficiency, showed localization of albumin mRNA over interstitial and ductular cells. Pancreatic hepatocytes were identified immediately after the rats were returned to a normal diet and gradually increased in number. The hepatocytes occupied almost 60% of the pancreatic volume by 8 weeks. During the early recovery phase, hepatocytes were identified in ductules as well as in the interstitium. Based on these studies, it is concluded that both the ductular cells and interstitial cells, which resemble oval cells of liver, are capable of transforming into pancreatic hepatocytes and these cells may be considered stem-cell equivalent. 相似文献
12.
Basal cell hyperplasia and basal cell carcinoma of the prostate: a comprehensive review and discussion of a case with c-erbB-2 expression
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Montironi R Mazzucchelli R Stramazzotti D Scarpelli M López Beltran A Bostwick DG 《Journal of clinical pathology》2005,58(3):290-296
Prostatic basal cell proliferations range from ordinary basal cell hyperplasia (BCH) to florid basal cell hyperplasia to basal cell carcinoma. The distinction between these forms of BCH, including the variant with prominent nucleoli (formerly called atypical BCH), and basal cell carcinoma depends on morphological and immunohistochemical criteria and, in particular, on the degree of cell proliferation. In florid BCH, the proliferation index is intermediate between ordinary BCH and basal cell carcinoma. Immunohistochemistry is also useful for identifying the cell composition of the basal cell proliferations, including the basal cell nature of the cells, their myoepithelial differentiation, and c-erbB-2 oncoprotein expression. Based on the information derived from the literature and on the appearance and follow up of the case presented here, florid BCH might represent a lesion with an intermediate position between ordinary BCH and basal cell carcinoma. However, criteria useful for the identification of those cases with a true precursor nature are not available. In general, basal cell carcinoma is seen as a low grade carcinoma. The immunohistochemical expression of the c-erbB-2 oncoprotein, similar to that seen in breast cancer, might have therapeutic importance. 相似文献
13.
The GAP-related domain of tuberin, the product of the TSC2 gene, is a target for missense mutations in tuberous sclerosis 总被引:5,自引:0,他引:5
Maheshwar MM; Cheadle JP; Jones AC; Myring J; Fryer AE; Harris PC; Sampson JR 《Human molecular genetics》1997,6(11):1991-1996
Tuberous sclerosis is an autosomal dominant trait in which the
dysregulation of cellular proliferation and differentiation results in the
development of hamartomatous growths in many organs. The TSC2 gene is one
of two genes determining tuberous sclerosis. Inactivating germline
mutations of TSC2 in patients with tuberous sclerosis and somatic loss of
heterozygosity at the TSC2 locus in the associated hamartomas indicate that
TSC2 functions as a tumour suppressor gene and that loss of function is
critical to expression of the tuberous sclerosis phenotype. The TSC2
product, tuberin, has a region of homology with the GTPase activating
protein rap1GAP and stimulates the GTPase activity of rap1a and rab5a in
vitro. Here we show that the region of homology between tuberin and human
rap1GAP and the murine GAP mSpa1 is more extensive than previously reported
and spans approximately 160 amino acid residues encoded within exons 34-38
of the TSC2 gene. Single strand conformation polymorphism analysis of these
exons in 173 unrelated patients with tuberous sclerosis and direct
sequencing of variant conformers together with study of additional family
members enabled characterisation of disease associated mutations in 14
cases. Missense mutations, which occurred in exons 36, 37 and 38 were
identified in eight cases, four of whom shared the same recurrent change
P1675L. Each of the five different missense mutations identified was shown
to occur de novo in at least one sporadic case of tuberous sclerosis. The
high proportion of missense mutations detected in the region of the TSC2
gene encoding the GAP-related domain supports its key role in the
regulation of cellular growth.
相似文献
14.
Berry V; Ionides AC; Moore AT; Plant C; Bhattacharya SS; Shiels A 《Human molecular genetics》1996,5(3):415-419
Inherited cataract is a clinically and genetically heterogeneous disease.
Here we report the identification of a new locus for an autosomal dominant
anterior polar cataract on the short arm of chromosome 17. To map this new
locus we performed genetic linkage analysis with microsatellite markers in
a four-generation pedigree. After exclusion of seven candidate loci for
cataract, we obtained significant positive LOD scores for markers D17S849
(Z = 4.01 / theta = 0.05) and D17S796 (Z = 4.17 / theta = 0.05). Multipoint
analysis gave a maximum LOD score of 5.2 (theta max = 0.06) between these
two markers. From haplotype analysis, the cataract locus lies in the 13 cM
interval between markers D17S849 and D17S796. This study provides the first
genetic mapping of an autosomal dominant anterior polar cataract.
相似文献
15.
Background
Genetic polymorphisms of the TCF7L2 gene are strongly associated with large increments in type 2 diabetes risk in different populations worldwide. In this study, we aimed to confirm the effect of the TCF7L2 polymorphism rs7903146 on diabetes risk in a Brazilian population and to assess the use of this genetic marker in improving diabetes risk prediction in the general population. 相似文献16.
Marjolijn Bornebroek Joost Haan Marion LC Maat-Schieman Sjoerd G Van Duinen Raymund AC Roos 《Brain pathology (Zurich, Switzerland)》1996,6(2):111-114
Hereditary cerebral hemorrhage with amyloidosis - Dutch type (HCHWA-D) is an autosomal dominant disease caused by deposition of β-amyloid in the leptomeningeal arteries and cortical arterioles, in addition to preamyloid deposits and amyloid plaques in the brain parenchyma.
The disease is due to a point mutation at codon 693 of the amyloid precursor protein (βPP) gene at chromosome 21. Since this point mutation is diagnostic for HCHWA-D, presymptomatic testing is feasible and offered, together with genetic counselling and psychological support, to subjects at risk. HCHWA-D is clinically characterized by recurrent strokes, in addition to dementia, which can occur after the first stroke but also preceding it. Radiological studies revealed focal lesions (hemorrhages, hemorrhagic and non-hemorrhagic infarctions) and diffuse white matter damage. Diffuse white matter hyperintensities on MRI are an early symptom of HCHWA-D since they have been found on MRI scans of subjects who had not suffered a stroke.
The presence of the diagnostic point mutation makes HCHWA-D a useful model to study the effects of cerebral amyloid angiopathy in vivo. The characteristic pathological abnormalities and its implications for Alzheimer's disease will be discussed in Part II of this article 相似文献
The disease is due to a point mutation at codon 693 of the amyloid precursor protein (βPP) gene at chromosome 21. Since this point mutation is diagnostic for HCHWA-D, presymptomatic testing is feasible and offered, together with genetic counselling and psychological support, to subjects at risk. HCHWA-D is clinically characterized by recurrent strokes, in addition to dementia, which can occur after the first stroke but also preceding it. Radiological studies revealed focal lesions (hemorrhages, hemorrhagic and non-hemorrhagic infarctions) and diffuse white matter damage. Diffuse white matter hyperintensities on MRI are an early symptom of HCHWA-D since they have been found on MRI scans of subjects who had not suffered a stroke.
The presence of the diagnostic point mutation makes HCHWA-D a useful model to study the effects of cerebral amyloid angiopathy in vivo. The characteristic pathological abnormalities and its implications for Alzheimer's disease will be discussed in Part II of this article 相似文献
17.
Variations of the origin of the artery of the sinoatrial node in normal human hearts 总被引:8,自引:0,他引:8
Summary The artery of the sino-atrial node was studied in 100 normal human hearts after injection of each coronary artery with coloured gelatine containing a radiopaque substance. The hearts belonged to 69 males and 31 females, being 64 Caucasians and 36 non-Caucasians (Negroes and Mulattoes) whose age ranged from 7 to 80 years. Since the individuals had committed suicide or were victims of accidents, their hearts, after pathologists' evaluation, were considered normal. The sinoatrial node of the normal human heart is supplied by the right coronary artery more frequently (58%±4.9% of the cases) than by the left (42%±4.9). The right anterior medial atrial artery, originating from the right coronary at the level of the medial third of the right anterior quadrant of the atrial dome, is most frequently (50%±5) responsible for the blood supply of the sinoatrial node. Among the branches of the left coronary artery, the left anterior medial atrial artery, originating at the level of the medial third of the left. anterior quadrant of the atrial cupola, was the most frequent blood supplier (25%±4.3) of the sinoatrial node. The origin of the artery of the sinoatrial node from the proximal portion or trunk of the left coronary artery was less frequent (12%±3.2) than the origin from the circumflex artery (30%±4.5). Neither sex nor race influenced the variations of the origin of the sino-atrial node.
Variations d'origine de l'artère du noeud sinu-atrial du coeur humain normal
Résumé L'a. du noeud sinu-atrial a été étudiée sur 100 coeurs humains normaux après injection de chaque a. coronaire à la gélatine colorée additionnée d'une substance radio-opaque. Les coeurs provenaient de 69 hommes et 31 femmes, 64 caucasiens et 36 non caucasiens (nègres et mulâtres) âgés de 7 à 80 ans. Ces sujets étant décédés par suicide ou des suites d'accidents, leurs coeurs ont été considérés comme normaux après examen anatomo-pathologique. Le noeud sinu-atrial du coeur humain est vascularisé par l'a. coronaire droite plus fréquemment (58 %±4,9) que par l'a. coronaire gauche (42 %±4). L'a. atriale antéro-médiale droite, issue de l'a. coronaire droite au niveau du tiers médial du quadrant antérieur droit du dôme atrial est l'artère la plus fréquemment en cause (50 %±5) dans la vascularisation du noeud sinuatrial. Parmi les branches de l'a. coronaire gauche, l'a. atriale antéro-médiale gauche, née au niveau du tiers médial du quadrant antérieur gauche du dôme atrial, était la branche la plus fréquemment en cause (25 %±4,3) dans la vascularisation du noeud sinu-atrial. La naissance de l'a. du noeud sinu-atrial à partir de la partie proximale ou du tronc de l'a. coronaire gauche était moins fréquente (12 %±3,2) que son origine à partir du rameau circonflexe (30 %±4,5). Les variations d'origine de l'a. du noeud sinu-atrial n'apparaissaient pas influencées par le sexe ou la race.相似文献
18.
Viability of partially damaged human embryos after cryopreservation 总被引:10,自引:13,他引:10
Van den Abbeel E; Camus M; Van Waesberghe L; Devroey P; Van Steirteghem AC 《Human reproduction (Oxford, England)》1997,12(9):2006-2010
In our centre, embryos are judged to have survived cryopreservation if at
least half of the initial number of blastomeres remain intact. Therefore
both fully intact and partially damaged embryos are transferred. The aim of
this study was to investigate the viability of partially damaged human
embryos after cryopreservation. We retrospectively analysed the
implantation and in-vivo development of embryos which were either fully
intact or had lost some blastomeres after cryopreservation. Oocytes were
collected following stimulation with the gonadotrophin-releasing hormone
(GnRH)-agonist Buserelin and human menopausal gonadotrophin. Supernumerary
multicellular embryos with not more than 20% of their volume filled with
anucleate fragments were frozen on day 2 or day 3 of the cycle using a slow
cooling procedure with dimethylsulphoxide as the cryoprotectant. Following
slow thawing, 431 fully intact embryos were transferred in 314 embryo
transfer procedures and 488 partially damaged embryos were transferred in
327 such procedures. The percentage of gestational sacs with fetal
heartbeat obtained after transfer of fully intact embryos was almost three
times higher than that after transfer of partially damaged embryos (11.4
versus 3.5%). Forty-five children (birth rate 10% per embryo transfer) were
born after transfer of fully intact embryos and 14 after transfer of
embryos from which some blastomeres had been lost following
cryopreservation. In conclusion, although children have been delivered
after transfer of partially damaged embryos, the aim of a cryopreservation
programme must be to obtain fully intact embryos after thawing.
相似文献
19.
Human pancreatic adenocarcinoma line Capan-1 in tissue culture and the nude mouse: morphologic, biologic, and biochemical characteristics 总被引:2,自引:0,他引:2
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A P Kyriazis A A Kyriazis D G Scarpelli J Fogh M S Rao R Lepera 《The American journal of pathology》1982,106(2):250-260
Human pancreatic ductal adenocarcinoma line Capan-1 was studied in tissue culture and the nude mouse. In tissue culture, the neoplastic cells grew as large epithelial-like mucin-producing cells. Subcutaneous and intraperitoneal transplantation of neoplastic cells into nude mice resulted in tumor formation characterized by marked invasiveness and distant metastases. Histologically, the tumor appeared as a well-differentiated mucin-producing adenocarcinoma morphologically resembling the tumor of origin. Chromosomal analysis showed a human karyotype with a chromosome number between 51-61. Lactate dehydrogenase and beta 2-microglobulin used as tumor markers were present in both tissue culture and the serum of tumor-bearing mice. The neoplasm, which was characterized by an increased level of cAMP, had lost completely the ability to respond to secretin stimulation. The tumor grown in the nude mouse was resistant to treatment with 5-fluorouracil, behavior identical to that of the original tumor. Diphtheria toxin resulted in complete tumor destruction. Because Capan-1 tumor grown in the nude mouse shows morphologic, biologic, and biochemical characteristics similar to the tumor of origin, it may be an invaluable tool in furthering understanding of the biology of human pancreatic cancer. 相似文献
20.