scholarly journals Molecules and membranes: Emerging details shed light on mammalian autophagy

2012 ◽  
Vol 34 (2) ◽  
pp. 4-7
Author(s):  
Sharon A. Tooze
Keyword(s):  
Electron Microscopy ◽  
Human Disease ◽  
Lysosomal Enzymes ◽  
Pivotal Role ◽  
Degradative Pathway ◽  
The 1950S ◽  
Shed Light

Autophagy, which literally means ‘self eating’, is a highly conserved intracellular degradative process mediated by lysosomal enzymes. Autophagy was identified using electron microscopy in the 1950s by cell biologists studying the lysosome and it was recognized as a lysosomal degradative pathway (for a review of the original publications, see Tooze et al.1) Recently, a number of key findings have elucidated the pivotal role played by autophagy in tissue homoeostasis and human disease, such as cancer, neurodegeneration, infection, immunity and aging2. Autophagy is also tightly linked to neonatal survival and cellular metabolism3.

scholarly journals Insights into Mycobacterium leprae Proteomics and Biomarkers—An Overview

Proteomes ◽  
2021 ◽  
Vol 9 (1) ◽  
pp. 7
Author(s):  
Sakshi Gautam ◽  
Devesh Sharma ◽  
Anjana Goel ◽  
Shripad A. Patil ◽  
Deepa Bisht
Keyword(s):  
Early Diagnosis ◽  
Causative Agent ◽  
Mycobacterium Leprae ◽  
Pivotal Role ◽  
New Biomarkers ◽  
Shed Light

Although leprosy is curable, the identification of biomarkers for the early diagnosis of leprosy would play a pivotal role in reducing transmission and the overall prevalence of the disease. Leprosy-specific biomarkers for diagnosis, particularly for the paucibacillary disease, are not well defined. Therefore, the identification of new biomarkers for leprosy is one of the prime themes of leprosy research. Studying Mycobacterium leprae, the causative agent of leprosy, at the proteomic level may facilitate the identification, quantification, and characterization of proteins that could be potential diagnostics or targets for drugs and can help in better understanding the pathogenesis. This review aims to shed light on the knowledge gained to understand leprosy or its pathogen employing proteomics and its role in diagnosis.

scholarly journals Comparative approaches to the study of physiology: Drosophila as a physiological tool

2013 ◽  
Vol 304 (3) ◽  
pp. R177-R188 ◽  
Author(s):  
Wendi S. Neckameyer ◽  
Kathryn J. Argue
Keyword(s):  
Gene Expression ◽  
Drosophila Melanogaster ◽  
Pattern Formation ◽  
Signaling Pathways ◽  
Human Disease ◽  
Cognitive Disorders ◽  
Model System ◽  
Critical Questions ◽  
Developmental Signaling ◽  
Shed Light

Numerous studies have detailed the extensive conservation of developmental signaling pathways between the model system, Drosophila melanogaster, and mammalian models, but researchers have also profited from the unique and highly tractable genetic tools available in this system to address critical questions in physiology. In this review, we have described contributions that Drosophila researchers have made to mathematical dynamics of pattern formation, cardiac pathologies, the way in which pain circuits are integrated to elicit responses from sensation, as well as the ways in which gene expression can modulate diverse behaviors and shed light on human cognitive disorders. The broad and diverse array of contributions from Drosophila underscore its translational relevance to modeling human disease.

DIFFERENTIATING ‘BUSHMEN’ FROM ‘BANTUS’: IDENTITY-BUILDING IN WEST CAPRIVI, NAMIBIA, 1930–89

2009 ◽  
Vol 50 (3) ◽  
pp. 417-436 ◽  
Author(s):  
JULIE J. TAYLOR
Keyword(s):  
Political Authority ◽  
Ethnic Identities ◽  
Political Factors ◽  
The 1950S ◽  
Liberation Struggle ◽  
State Interventions ◽  
Shed Light

ABSTRACTThis article focuses on the historical and political factors that shaped Khwe (San) and Mbukushu ethnic identities and their interrelationship between 1938 and 1989 in west Caprivi, Namibia. While acknowledging the multi-authored nature of identity-building, the article demonstrates that the colonial and apartheid states made significant contributions to the construction of ethnicity in west Caprivi through veterinary interventions in the 1930s and apartheid policies regarding ‘Bushmen’ in the 1950s, and by securing Khwe collaboration during Namibia's liberation struggle in the 1970s and 1980s. These state interventions, together with Khwe and Mbukushu responses to them, also shed light on why land and political authority became so central to struggles between the two groups.

Translator’s Note

2019 ◽  
pp. 227-228
Author(s):  
Naomi Seidman
Keyword(s):  
The World ◽  
The 1950S ◽  
Shed Light

IN 1933 the Central Secretariat of Bnos Agudath Israel in Poland issued Sarah Schenirer’s Collected Writings, after advertising the upcoming publication in the pages of the Bais Yaakov Journal. The book included many articles that had previously appeared in the journal or elsewhere in Bais Yaakov publications; among them were reflections on Jewish themes, reports on events important to the world of Bais Yaakov and Bnos, and ethical instructions to young pupils. But it also included previously unpublished writings, including a brief but fascinating memoir that shed light on Sarah Schenirer’s childhood and on the beginnings of the Bais Yaakov movement. As a frontispiece, the book included a drawing of Sarah Schenirer, one which circulated widely in the movement in the absence of a photograph (it was well known that she refused to have her photograph taken). Advertisements for the upcoming volume sometimes provided a table of contents, which promised that it would include excerpts from Schenirer’s diary. In fact, those excerpts did not appear in the published work, although a few entries—whether the ones originally intended for publication or others is not clear—did appear in the 1950s in Hebrew translation. For more on this diary, see Appendix A....

scholarly journals Identification of primary lysosomes in human megakaryocytes and platelets

Blood ◽  
1982 ◽  
Vol 59 (3) ◽  
pp. 472-481 ◽  
Author(s):  
ME Bentfeld-Barker ◽  
DF Bainton
Keyword(s):  
Electron Microscopy ◽  
Bone Marrow ◽  
Lysosomal Enzymes ◽  
Human Platelets ◽  
Variable Size ◽  
Golgi Region ◽  
Normal Human ◽  
The Subject ◽  
Cytoplasmic Maturation ◽  
Normal Human Bone Marrow

Abstract The presence of lysosomal enzymes in human platelets is well documented; the identity of the “lysosome,” however, has been the subject of some disagreement. In order to determine the time of appearance and subcellular localization of two lysosomal enzymes in megakaryocytes (MK) and platelets, we examined normal human bone marrow and blood by electron microscopy and cytochemistry. Acid phosphatase (AcPase) was present in the Golgi region in the youngest recognizable MK, as well as in those with a considerable degree of cytoplasmic maturation. Heavy reaction product was usually confined to one or two Golgi-associated cisternae and coated vesicles; other Golgi cisternae were sometimes lightly reactive. In mature MK, reaction product was limited to vesicles of variable size, but smaller than alpha-granules. Another lysosomal enzyme, arylsulfatase (AS), was localized in similar small vesicles in MK of all stages; it could not be demonstrated in the Golgi complex. Vesicles containing AS were also found in about 25% of platelet profiles, whereas vesicles containing AcPase were found in only about 15% of platelet profiles. The alpha-granules of all MK and platelets examined were negative for both enzymes. We conclude that the enzyme-containing vesicles in these cells constitute the lysosomes and that they are distinct from other platelet organelles. Since there was no evidence that they had participated in any digestive event, we believe that they are primary lysosomes, whose contents are secreted during platelet aggregation and the release reaction.

TEM Study of Mg-Doped Bulk GaN Crystals

1999 ◽  
Vol 572 ◽  
Author(s):  
Z. Liliental-Weber ◽  
M. Benamara ◽  
S. Ruvimov ◽  
J. H. Mazur ◽  
J. Washburn ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Growth Rate ◽  
Stacking Faults ◽  
High Energy ◽  
Defect Distribution ◽  
Transmission Electron ◽  
Bulk Gan ◽  
Shed Light ◽  
Mg Doped

ABSTRACTTransmission electron microscopy was applied to cross-sectioned samples to study surface morphology, sample polarity and defect distribution in bulk GaN samples doped with Mg. These crystals were grown from a Ga melt under high hydrostatic pressure of Nitrogen. It was shown that the types of defects and their distribution along the c-axis depends strongly on sample polarity. Based on this finding the growth rate along the c-axis for the two polar directions was compared and shown to be approximately ten times larger for Ga polarity than for N-polarity. In the part of the crystals with Ga polarity pyramidal defects with a base consisting of high energy stacking faults were found. The parts of the crystals grown with Npolarity were either defect free or contained regularly spaced stacking faults. Growth of these regularly spaced cubic monolayers is polarity dependent; this structure was formed only for the growth with N polarity and only for the crystals doped with Mg. Formation of this superstructure is similar to the polytypoid structure formed in AlN crystals rich in oxygen. It is also likely that oxygen can decorate the cubic monolayers and compensate Mg. This newly observed structure may shed light on the difficulties of p-doping in GaN:Mg.

Ultrastructure of Two Cases of Anaplastic Giant Cell Tumor of the Human Thyroid Gland

1974 ◽  
Vol 32 ◽  
pp. 40-41
Author(s):  
Gaal J.M. ◽  
Horvath E. ◽  
Kovacs K.
Keyword(s):  
Electron Microscopy ◽  
Giant Cell Tumor ◽  
Giant Cell ◽  
Light And Electron Microscopy ◽  
Cell Tumor ◽  
Human Thyroid ◽  
Dense Matrix ◽  
Size And Morphology ◽  
Mitotic Figures ◽  
Shed Light

Two cases of anaplastic giant cell tumor of the thyroid have "been studied by light and electron microscopy in order to shed light on its morphogenesis. The tumors were removed by surgery from 67 and 75 year old women respectively.By light microscopy the tumors corresponded to anaplastic giant cell tumor of the thyroid, exhibiting marked pleomorphism, numerous mitotic figures, and foci of necrosis.Electron microscopy revealed that the tumors were composed of cells varying in size and morphology (Fig.1.). The nuclei were large and multilobulated; bizarre forms, occupying a considerable part of the cells, were not infrequent. Nucleoli were large and dense. The mitochondria were not numerous. They were rod shaped or elongated with widely spaced transverse cristae and moderately electron dense matrix. Spherulated, swollen forms were also observed. The rough surfaced endoplasmic reticulum (RER) was abundant in many cells. It consisted of parallel membranes with numerous ribosomes studded on their external aspects.

Preparing for a Postmethod Pedagogy: A Transformative Approach to Curriculum Development

2016 ◽  
Vol 6 (3) ◽  
pp. 586
Author(s):  
Arash V. Naeini ◽  
Nima Shakouri
Keyword(s):  
Curriculum Development ◽  
Social Economic ◽  
Pivotal Role ◽  
Dynamic Learning ◽  
Individual Teacher ◽  
Transformative Process ◽  
Transformative Approach ◽  
Shed Light

The three parameters of postmethod pedagogy proposed by Kumaravadivelu (2001), particularly a pedagogy of possibility, are in line with and drew on the works of such critical pedagogists as Giroux (1988) whose idea of transformative intellectuals viewed it rightful for every individual teacher and learner to actively participate in the process of learning with their entire social, economic and political experiences; and even make reformations to the direction of pedagogy based on their understanding. However, curriculum development, as an integral part of pedagogy, may inhibit this transformative and dynamic learning by restricting teachers to set and prefabricated materials and guidelines. Nonetheless, teachers play a pivotal role in the realization of this transformative process since they are the executive recipients of curricula. This paper is an attempt to shed light on a transformative approach to curriculum development and holds, a transformative approach to curriculum development requires teachers to have a hand in curriculum development when they are invited by the curriculum to act so; and adapt or transform the curriculum when they are constrained by it.

scholarly journals SEQUENTIAL DEGRANULATION OF THE TWO TYPES OF POLYMORPHONUCLEAR LEUKOCYTE GRANULES DURING PHAGOCYTOSIS OF MICROORGANISMS

1973 ◽  
Vol 58 (2) ◽  
pp. 249-264 ◽  
Author(s):  
Dorothy Ford Bainton
Keyword(s):  
Electron Microscopy ◽  
Alkaline Phosphatase ◽  
Polymorphonuclear Leukocyte ◽  
Lysosomal Enzymes ◽  
Marker Enzyme ◽  
Optimal Conditions ◽  
Alkaline Ph ◽  
Enzyme Content ◽  
Specific Granules ◽  
Acid Range

The sequential discharge of neutrophilic polymorphonuclear leukocyte (PMN) granules—azurophils and specifics—was investigated by electron microscopy and cytochemistry. Thus the enzyme content of PMN phagocytic vacuoles was determined at brief intervals after phagocytosis of bacteria, utilizing peroxidase as a marker enzyme for azurophil granules, and alkaline phosphatase for specifics. At 30 s, approximately half the phagocytic vacuoles were reactive for alkaline phosphatase, whereas none contained peroxidase. Peroxidase-containing vacuoles were rarely seen at 1 min, but by 3 min, vacuoles containing both enzymes were consistently present. Alkaline phosphatase was found in both small and large vacuoles, whereas peroxidase was visible only in large ones. By 10 min, very big phagocytic vacuoles containing considerable amounts of reaction product for both enzymes were evident. These observations indicate that the two types of PMN granules discharge in a sequential manner, specific granules fusing with the vacuole before azurophils. In an earlier paper, we reported that the pH of phagocytic vacuoles drops to 6.5 within 3 min and to ∼4 within 7–15 min. Substances known to be present in specific granules (alkaline phosphatase, lysozyme, and lactoferrin) function best at neutral or alkaline pH, whereas most of those contained in azurophil granules (i.e., peroxidase and the lysosomal enzymes) have pH optima in the acid range. Hence the sequence of granule discharge roughly parallels the change in pH, thereby providing optimal conditions for coordinated activity of granule contents.

scholarly journals Altering ethanol pharmacokinetics to treat alcohol use disorder: Can you teach an old dog new tricks?

2017 ◽  
Vol 31 (7) ◽  
pp. 812-818 ◽  
Author(s):  
Carolina L Haass-Koffler ◽  
Fatemeh Akhlaghi ◽  
Robert M Swift ◽  
Lorenzo Leggio
Keyword(s):  
Alcohol Use ◽  
Alcohol Use Disorder ◽  
Mechanisms Of Action ◽  
The 1950S ◽  
Viable Approach ◽  
Original Approach ◽  
Shed Light

Disulfiram was the first pharmacotherapy approved to treat alcohol use disorder in the 1950s. Disulfiram alters ethanol pharmacokinetics and causes uncomfortable reactions (e.g. headache, tachycardia, nausea, flushing and hypotension) when alcohol is consumed. Subsequently, a better understanding of the neurobiological pathways involved in alcohol use disorder led to the development of other medications (e.g. naltrexone and acamprosate). These neurobiological-based medications act on alcohol use disorder-related phenotypes including craving, stress, and/or withdrawal. The original approach to treat alcohol use disorder, by altering ethanol pharmacokinetics has been much less investigated. Recent research on ethanol pharmacokinetics has shed light on the mechanisms of action underlying alcohol use disorder and how some medications that alter ethanol pharmacokinetics may be helpful in treating alcohol use disorder. This review summarizes and discusses the complex pharmacokinetics of ethanol, and proposes that altering ethanol pharmacokinetics via novel pharmacological approaches may be a viable approach to treat alcohol use disorder.

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