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Abeta oligomer-mediated long-term potentiation impairment involves protein phosphatase 1-dependent mechanisms.

https://arctichealth.org/en/permalink/ahliterature162439
Source
J Neurosci. 2007 Jul 18;27(29):7648-53
Publication Type
Article
Date
Jul-18-2007
Author
Marlen Knobloch
Mélissa Farinelli
Uwe Konietzko
Roger M Nitsch
Isabelle M Mansuy
Author Affiliation
Division of Psychiatry Research, University of Zurich, 8008 Zurich, Switzerland.
Source
J Neurosci. 2007 Jul 18;27(29):7648-53
Date
Jul-18-2007
Language
English
Publication Type
Article
Keywords
Age Factors
Amyloid Precursor Protein Secretases - genetics
Amyloid beta-Peptides - chemistry - metabolism - ultrastructure
Analysis of Variance
Animals
Calcium-Calmodulin-Dependent Protein Kinase Type 2
Calcium-Calmodulin-Dependent Protein Kinases - genetics
Dose-Response Relationship, Radiation
Electric Stimulation - methods
Excitatory Postsynaptic Potentials - drug effects - physiology
Gene Expression Regulation - genetics
Hippocampus - cytology
Humans
Long-Term Potentiation - genetics - physiology - radiation effects
Mice
Mice, Transgenic
Microscopy, Electron, Transmission - methods
Neurons - drug effects - physiology
Patch-Clamp Techniques
Phosphoprotein Phosphatases - physiology
Presenilin-1 - genetics
Protein Phosphatase 1
Reverse Transcriptase Polymerase Chain Reaction - methods
Abstract
Amyloid beta (Abeta) oligomers are derived from proteolytic cleavage of amyloid precursor protein (APP) and can impair memory and hippocampal long-term potentiation (LTP) in vivo and in vitro. They are recognized as the primary neurotoxic agents in Alzheimer's disease. The mechanisms underlying such toxicity on synaptic functions are complex and not fully understood. Here, we provide the first evidence that these mechanisms involve protein phosphatase 1 (PP1). Using a novel transgenic mouse model expressing human APP with the Swedish and Arctic mutations that render Abeta more prone to form oligomers (arcAbeta mice), we show that the LTP impairment induced by Abeta oligomers can be fully reversed by PP1 inhibition in vitro. We further demonstrate that the genetic inhibition of endogenous PP1 in vivo confers resistance to Abeta oligomer-mediated toxicity and preserves LTP. Overall, these results reveal that PP1 is a key player in the mechanisms of AD pathology.
PubMed ID
17634359 View in PubMed
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Abnormal glycosylation and altered Golgi structure in colorectal cancer: dependence on intra-Golgi pH.

https://arctichealth.org/en/permalink/ahliterature19175
Source
FEBS Lett. 2002 Apr 10;516(1-3):217-24
Publication Type
Article
Date
Apr-10-2002
Author
Sakari Kellokumpu
Raija Sormunen
Ilmo Kellokumpu
Author Affiliation
Department of Biochemistry, University of Oulu, P.O. Box 3000, FIN-90014, Oulu, Finland. sakari.kellokumpu@oulu.fi
Source
FEBS Lett. 2002 Apr 10;516(1-3):217-24
Date
Apr-10-2002
Language
English
Publication Type
Article
Keywords
Animals
Antigens, Tumor-Associated, Carbohydrate - metabolism
Breast Neoplasms - immunology - metabolism - ultrastructure
COS Cells
Cells, Cultured
Colorectal Neoplasms - immunology - metabolism - ultrastructure
Female
Glycosylation
Golgi Apparatus - immunology - metabolism - ultrastructure
Humans
Hydrogen-Ion Concentration
Ion Transport
Microscopy, Electron
Rats
Research Support, Non-U.S. Gov't
Tumor Cells, Cultured
Abstract
Abnormal glycosylation of cellular glycoconjugates is a common phenotypic change in many human tumors. Here, we explore the possibility that an altered Golgi pH may also be responsible for these cancer-associated glycosylation abnormalities. We show that a mere dissipation of the acidic Golgi pH results both in increased expression of some cancer-associated carbohydrate antigens and in structural disorganization of the Golgi apparatus in otherwise normally glycosylating cells. pH dependence of these alterations was confirmed by showing that an acidification-defective breast cancer cell line (MCF-7) also displayed a fragmented Golgi apparatus, whereas the Golgi apparatus was structurally normal in its acidification-competent subline (MCF-7/AdrR). Acidification competence was also found to rescue normal glycosylation potential in MCF-7/AdrR cells. Finally, we show that abnormal glycosylation is also accompanied by similar structural disorganization and fragmentation of the Golgi apparatus in colorectal cancer cells in vitro and in vivo. These results suggest that an inappropriate Golgi pH may indeed be responsible for the abnormal Golgi structure and lowered glycosylation potential of the Golgi apparatus in malignant cells.
PubMed ID
11959136 View in PubMed
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The acetic acid test in evaluation of subclinical genital papillomavirus infection: a comparative study on penoscopy, histopathology, virology and scanning electron microscopy findings.

https://arctichealth.org/en/permalink/ahliterature24490
Source
Genitourin Med. 1992 Apr;68(2):90-9
Publication Type
Article
Date
Apr-1992
Author
A. Wikström
M A Hedblad
B. Johansson
M. Kalantari
S. Syrjänen
M. Lindberg
G. von Krogh
Author Affiliation
Department of Dermatovenereology, Karolinska Hospital, Stockholm, Sweden.
Source
Genitourin Med. 1992 Apr;68(2):90-9
Date
Apr-1992
Language
English
Publication Type
Article
Keywords
Acetic Acid
Acetic Acids - diagnostic use
Blotting, Southern
Comparative Study
Endoscopy
Humans
Male
Microscopy, Electron, Scanning
Papillomavirus
Penile Diseases - diagnosis - pathology
Polymerase Chain Reaction
Predictive value of tests
Sensitivity and specificity
Tumor Virus Infections - diagnosis - pathology
Abstract
OBJECTIVES--To evaluate colposcopic criteria in acetowhite lesions of the penis ("penoscopy") for the diagnosis of subclinical genitoanal papillomavirus infection (GPVI) compared with histopathological criteria of HPV involvement and to various hybridisation assays for HPV DNA detection, and to depict typical lesions by scanning electron microscopy. DESIGN--The study included 101 randomly selected male partners of females with known GPVI, or with penile symptoms such as itching, burning and dyspareunia who did not exhibit overt genital warts but appeared to be afflicted with acetowhite penile lesions after topical application of 5% acqueous acetic acid. Lesions were judged by penoscopy as either typical, conspicuous or nontypical for underlying HPV infection. Biopsy specimens from 91 men were examined by light microscopy and by either Southern blot (SB), polymerase chain reaction (PCR) and/or in situ hybridisation (ISH) assays for the presence of HPV DNA of the HPV types 6, 11, 16, 18, 31, 33 and 42 (Group A). From another ten men lesions clinically typical for GPVI were also examined topographically by scanning electronic microscopy (Group B). SETTING--The STD out-patient clinic of the Department of Dermatovenereology of Karolinska Hospital, Stockholm, Sweden. RESULTS--Group A Seventy eight (86%) of the biopsied lesions met the penoscopy criteria of being either typical of or conspicuous for GVPI. The agreement between penoscopy and histopathology was fairly good, as HPV diagnosis was made by both methods in 56 (62%) of the cases. The reliability of applying strict colposcopic hallmarks was further substantiated by the finding that 55 (60%) of the biopsy specimens taken from penoscopically typical/conspicuous lesions contained HPV DNA. However, there are diagnostic pitfalls for the acetic acid test. Coexistence of an eczematoid reaction with changes indicative of HPV influence was detected in six (7%) of the cases, while an inflammatory response only occurred in 17 (19%) of the specimens. Additional histopathological diagnoses (normal epithelium, lichen sclerosus et atrophicus, balanitis circinata parakeratotica, verruca plana) were established in another eight (9%) of the cases. Among the HPV DNA positive cases, all of the HPV types tested for were detected with the exception of HPV 18. A severe penile intraepithelial neoplasia (PIN III) was revealed in five (5%) of biopsies; HPV 16 was present in two and HPV 42 in one of these biopsy specimens. GROUP B--Scanning electron microscopy depiction harmonised with the penoscopy findings showing that subclinical GPVI characteristically exhibits a well demarcated, slightly elevated border and that the central area of lesions often displays a "groove" in which the epithelium appears to be thin with protrusions from beneath that probably represent capillaries. CONCLUSION--Use of the acetic acid test for evaluation of GPVI should be combined with a colposcopic evaluation based on strict topographic hallmarks, followed by a directed biopsy for light microscopic evaluation. We found that the positive predictive value of colposcopy was as high when correlated with histopathological findings (72%) as when virological methods were used, whether HPV DNA hybridisation testing was performed with the well established SB and ISH assays (45%), or by applying the newly introduced and highly sensitive PCR assay as well (71%). False positivity from the acetic acid test occurs and is mainly due to inflammatory conditions but also to the presence of other conditions. Epithelial fissures are evidently associated with some subclinical GPVI lesions and may potentially represent loci minores for infectious stimuli and perhaps facilitate the transmission of some blood-borne STDs. We prose that the term "papillomavirus balanoposthitis" should be used for penile HPV infection associated with inflammatory responses. Our study indicates that PIN III frequently occurs in a subclinical form and may be associated with not only previously identified "high-risk" HPV types such as type 16, but also with the HPV type 42 that has not previously been considered as oncogenic.
PubMed ID
1316310 View in PubMed
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Activity-induced dental modification in holocene siberian hunter-fisher-gatherers.

https://arctichealth.org/en/permalink/ahliterature100395
Source
Am J Phys Anthropol. 2010 Oct;143(2):266-78
Publication Type
Article
Date
Oct-2010
Author
Andrea Waters-Rist
Vladimir I Bazaliiskii
Andrzej Weber
Olga I Goriunova
M Anne Katzenberg
Author Affiliation
Department of Archaeology, University of Calgary, Calgary, Alberta, Canada, T2N-1N4. awaters@ucalgary.ca
Source
Am J Phys Anthropol. 2010 Oct;143(2):266-78
Date
Oct-2010
Language
English
Publication Type
Article
Keywords
Adult
Asia, Central
Chi-Square Distribution
Female
Fossils
Geography
History, Ancient
Humans
Male
Mandible
Microscopy, Electron, Scanning
Middle Aged
Occupations
Paleodontology
Sex Distribution
Siberia
Statistics, nonparametric
Tooth - anatomy & histology
Tooth Attrition
Abstract
The use of teeth as tools provides clues to past subsistence patterns and cultural practices. Five Holocene period hunter-fisher-gatherer mortuary sites from the south-western region of Lake Baikal, Siberia, Russian Federation, are observed for activity-induced dental modification (AIDM) to further characterize their adaptive regimes. Grooves on the occlusal surfaces of teeth are observed in 25 out of 123 individuals (20.3%) and were most likely produced during the processing of fibers from plants and animals, for making items such as nets and cordage. Regional variation in the frequency of individuals with occlusal grooves is found in riverine versus lakeshore sites. This variation suggests that production of material culture items differed, perhaps in relation to different fishing practices. There is also variation in the distribution of grooves by sex: grooves are found predominately in females, except at the Late Neolithic-Bronze Age river site of Ust'-Ida I where grooves are found exclusively in males. Occlusal grooves were cast using polyvinylsiloxane and maxillary canine impressions were examined by scanning electron microscopy (SEM) to determine striation patterns. Variation in striae orientation suggests that a variety of activities, and/or different manufacturing techniques, were involved in groove production. Overall, the variability in occlusal groove frequency, sex and regional distribution, and microscopic striae patterns, points to the multiplicity of activities and ways in which people used their mouths and teeth in cultural activities.
PubMed ID
20853480 View in PubMed
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Acute interstitial pneumonia in mink kits: experimental reproduction of the disease.

https://arctichealth.org/en/permalink/ahliterature4624
Source
Vet Pathol. 1986 Sep;23(5):579-88
Publication Type
Article
Date
Sep-1986
Author
S. Alexandersen
Source
Vet Pathol. 1986 Sep;23(5):579-88
Date
Sep-1986
Language
English
Publication Type
Article
Keywords
Acute Disease
Aleutian Mink Disease - pathology
Aleutian Mink Disease Virus - isolation & purification
Animals
Female
Immunoenzyme Techniques
Lung - pathology - ultrastructure
Male
Microscopy, Electron
Microscopy, Fluorescence
Mink
Pregnancy
Pregnancy Complications, Infectious - pathology - veterinary
Pulmonary Fibrosis - pathology - veterinary
Research Support, Non-U.S. Gov't
Abstract
Organ homogenates from kits that died of interstitial pneumonia were inoculated into adult Aleutian disease virus (ADV)-negative mink and shown to contain infectious ADV. Acute interstitial pneumonia was experimentally reproduced with the organ homogenate but only by inoculation of newborn kits born from ADV-negative dams. Older kits and kits from ADV-positive dams did not develop interstitial pneumonia, but later developed the classic form of Aleutian disease. Electron microscopic examination was done on purified suspensions of defined ADV isolates and on purified organ homogenates from kits with spontaneous or experimental interstitial pneumonia. In kits from both groups a virus, morphologically resembling the defined ADV isolates, was demonstrated. Findings of intranuclear inclusion bodies and intranuclear ADV antigen in alveolar type-II cells in affected lungs and the lack of immunologically mediated lesions suggest that lung lesions result from primary viral injury to alveolar type-II cells. Experiments also showed that infection of dams with ADV before pregnancy decreased the number of kits per mated dam and infection with ADV in mid-pregnancy caused fetal death, fetal resorption, or abortion.
PubMed ID
3022453 View in PubMed
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[Adrenal structure in the fetuses of humans living in the European North]

https://arctichealth.org/en/permalink/ahliterature59506
Source
Morfologiia. 1993 May-Jun;104(5-6):77-83
Publication Type
Article
Author
S G Sukhanov
N R Bunchak
Source
Morfologiia. 1993 May-Jun;104(5-6):77-83
Language
Russian
Publication Type
Article
Keywords
Adrenal Glands - embryology - metabolism - ultrastructure
Cold Climate
Comparative Study
English Abstract
Female
Fetal Death - embryology
Fetus
Gestational Age
Humans
Infant, Newborn
Male
Microscopy, Electron
Nuclear Proteins - metabolism
Organ Size
Russia
Abstract
The adrenals of 194 human fetuses of 17-40 weeks and newborn infants were studied by histological and morphometrical methods. The abortive material was taken at hospitals in the city of Arkhangelsk and regions beyond the Polar circle. The mass of adrenals was found to be reliably less as compared with the norms in middle latitudes, and the rate of increase of this index decreased in the dynamics of pregnancy. The microscopic and stereometric investigations have revealed decreased thickness of the cortex, adaptational and pathological changes of adrenocorticocytes. Little mass of the adrenals was associated in some cases with a premature formation of the cortex zones.
PubMed ID
8012542 View in PubMed
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Adsorption inhibition as a mechanism of freezing resistance in polar fishes.

https://arctichealth.org/en/permalink/ahliterature46812
Source
Proc Natl Acad Sci U S A. 1977 Jun;74(6):2589-93
Publication Type
Article
Date
Jun-1977
Author
J A Raymond
A L DeVries
Source
Proc Natl Acad Sci U S A. 1977 Jun;74(6):2589-93
Date
Jun-1977
Language
English
Publication Type
Article
Keywords
Acclimatization
Adsorption
Animals
Blood Proteins - physiology
Cold Climate
Fishes - physiology
Freezing
Glycoproteins - blood
Kinetics
Microscopy, Electron, Scanning
Molecular Weight
Protein Conformation
Research Support, U.S. Gov't, Non-P.H.S.
Research Support, U.S. Gov't, P.H.S.
Species Specificity
Abstract
Polar fishes are known to have serum proteins and glycoproteins that protect them from freezing, by a noncolligative process. Measurements of antifreeze concentrations in ice and scanning electron micrographs of freeze-dried antifreeze solutions indicate that the antifreezes are incorporated in ice during freezing. The antifreezes also have a pronounced effect on the crystal habit of ice grown in their presence. Each of four antifreezes investigated caused ice to grow in long needles whose axes were parallel to the ice c axis. Together these results indicate the antifreezes adsorb to ice surfaces and inhibit their growth. A model in which adsorbed antifreezes raise the curvature of growth steps on the ice surface is proposed to account for the observed depression of the temperature at which freezing occurs and agrees well with experimental observations. The model is similar to one previously proposed for other cases of crystal growth inhibition.
PubMed ID
267952 View in PubMed
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Adverse effects of Sudanese toombak vs. Swedish snuff on human oral cells.

https://arctichealth.org/en/permalink/ahliterature98857
Source
J Oral Pathol Med. 2010 Feb;39(2):128-40
Publication Type
Article
Date
Feb-2010
Author
Daniela Elena Costea
Ochiba Lukandu
Linh Bui
Muna Jaffar M Ibrahim
Raymond Lygre
Evelyn Neppelberg
Salah Osman Ibrahim
Olav Karsten Vintermyr
Anne Christine Johannessen
Author Affiliation
Section of Pathology, The Gade Institute, University of Bergen, Bergen, Norway. daniela.costea@gades.uib.no
Source
J Oral Pathol Med. 2010 Feb;39(2):128-40
Date
Feb-2010
Language
English
Publication Type
Article
Keywords
Adult
Annexin A5 - analysis
Apoptosis - drug effects
Cell Count
Cell Division - drug effects
Cell Line
Cell Proliferation - drug effects
Cell Shape - drug effects
Cell Survival - drug effects
Cells, Cultured
Coloring Agents - diagnostic use
DNA Breaks, Double-Stranded
Fibroblasts - cytology - drug effects
G2 Phase - drug effects
Humans
Keratinocytes - cytology - drug effects
Microscopy, Electron, Transmission
Mouth Mucosa - cytology - drug effects
Phosphatidylserines - analysis
Plant Extracts - adverse effects
Sudan
Sweden
Tobacco, Smokeless - adverse effects
Abstract
BACKGROUND: The high incidence of oral cancer in Sudan has been associated with the use of toombak, the local type of smokeless tobacco. However, its specific effects on human oral cells are not known. We aimed to investigate the effects of toombak on primary normal human oral keratinocytes, fibroblasts, and a dysplastic oral keratinocytic cell line, and to compare them with the effects induced by Swedish snuff. METHOD: Aqueous extracts were prepared from moist toombak and Swedish snuff and added in serial dilutions on in vitro monolayer cultured cells. Cell viability, morphology and growth, DNA double-strand breaks (gammaH2AX staining), expression of phosphatidylserine (Annexin V staining), and cell cycle were assessed after various exposure time periods. RESULTS: Significant decrease in cell number, occurrence of DNA double-strain breaks, morphological and biochemical signs of programmed cell death were detected in all oral cell types exposed to clinically relevant dilutions of toombak extract, although to a lesser extent in normal oral fibroblasts and dysplastic keratinocytes. G2/M-block was also detected in normal oral keratinocytes and fibroblasts exposed to clinically relevant dilutions of toombak extract. Swedish snuff extract had less adverse effects on oral cells, mainly at non-clinically relevant dilutions. CONCLUSION: This study indicates a potential for toombak, higher than for Swedish snuff, to damage human oral epithelium. Dysplastic oral keratinocytes were less sensitive than their normal counterparts, suggesting that they might have acquired a partially resistant phenotype to toombak-induced cytotoxic effects while still being prone to DNA damage that could lead to further malignant progression.
PubMed ID
19804503 View in PubMed
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[Age-dependent differences of the ultrastructural changes in the myocardium after hypoxical preconditioning and ischemia-reperfusion of the isolated heart in rats]

https://arctichealth.org/en/permalink/ahliterature84268
Source
Fiziol Zh. 2007;53(4):27-34
Publication Type
Article
Date
2007
Author
Portnychenko A H
Rozova K V
Vasylenko M I
Moibenko O O
Source
Fiziol Zh. 2007;53(4):27-34
Date
2007
Language
Ukrainian
Publication Type
Article
Keywords
Adaptation, Physiological
Aging - pathology
Animals
Anoxia - physiopathology
Male
Microscopy, Electron
Mitochondria, Heart - ultrastructure
Myocardial Reperfusion Injury - pathology - prevention & control
Myocardium - ultrastructure
Rats
Rats, Wistar
Abstract
Recently we evidenced the ability of acute systemic hypoxia to induce phenomenon of delayed cardioprotection in rats. Age-dependent peculiarities were studied in 6 and 12 month old rats exposed to hypoxical preconditioning (10% O2, 1 or 3 h). In 24 h isolated hearts were ischemized 30 min and then reperfuzed 40 min, with or without iNOS blocker 1,3-PBIT (50 nmol/l). It was shown that hypoxic preconditioning dose-dependently injured myocardial ultrastructure, and induced delayed cardioprotection, strongly marked after 3 h preconditioning. Blockade of iNOS as mediator of delayed cardioprotection led to mitochondrial stimulation and attenuated protection. In mature aged rats, myocardial injury and protection had been individually variable, mitochondria were more damaged and stimulated to biogenesis, and incomplete autophagy was typical as distinct from young rats.
PubMed ID
17902368 View in PubMed
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400 records – page 1 of 40.