scholarly journals Spermatogenesis in house mouse in a Robertsonian polymorphism zone

Reproduction ◽  
2010 ◽  
Vol 140 (4) ◽  
pp. 569-581 ◽  
Author(s):  
Ma Assumpció Sans-Fuentes ◽  
José García-Valero ◽  
Jacint Ventura ◽  
Ma José López-Fuster
Keyword(s):  
Diploid Number ◽  
Postzygotic Isolation ◽  
Homozygous State ◽  
Large Numbers ◽  
Structural Heterozygosity ◽  
Multilevel Sampling ◽  
Morphological Variables ◽  
Monobrachial Homology ◽  
Rb Translocations

Robertsonian (Rb) translocations can be important in speciation as a mechanism of postzygotic isolation between populations. Meiotic non-disjunction, gametogenic impairment, and association of impaired autosomal segments with sex chromosomes have been postulated as mechanisms responsible for reducing fertility in Rb mice. Quantitative histological studies needed to understand the role of Rb fusions in gametogenic impairment are scarce. Most research on Rb mice has analyzed meiotic non-disjunction of laboratory and wild-derived strains, which have complex or simple structural heterozygosity with large numbers of fusions. Using histological multilevel sampling, we examined spermatogenesis in mice from the Rb polymorphism area of Barcelona. We studied four chromosomal groups having: a) one Rb heterozygote fusion and 2n=39, b) one Rb heterozygote fusion and 2n=31, c) three Rb heterozygote fusions without monobrachial homology and with diploid number ranging from 2n=29 to 2n=37, and d) only Rb homozygote fusions with diploid number ranging from 2n=28 to 2n=30. Standard mice from the area surrounding the Rb zone were used as control. We analyzed morphological variables of the testes, relative frequency of stages in the seminiferous epithelium cycle, the ‘round spermatids:primary spermatocytes’ ratio, and other derived parameters. Our results reveal that structural homozygote mice and simple heterozygote mice having as few as one to three Rb fusions undergo greater germ cell death (GCD) than standard mice, suggesting that Rb fusions are related to increased GCD (in both the heterozygous and homozygous state) and may be the main cause of decreased gene flow between mice populations from this area.

Localization of Intracisternal a Particle Antigens in Neoplastic Cells and Preimplantation Mouse Embryos

1980 ◽  
Vol 38 ◽  
pp. 696-697
Author(s):  
Thomas T.F. Huang ◽  
Patricia G. Calarco
Keyword(s):  
Endoplasmic Reticulum ◽  
Normal Development ◽  
Mouse Embryos ◽  
Neoplastic Cells ◽  
Large Numbers ◽  
Preimplantation Mouse Embryos ◽  
Preimplantation Mouse ◽  
Intracisternal A Particle ◽  
Normal Feature

The stage specific appearance of a retravirus, termed the Intracisternal A particle (IAP) is a normal feature of early preimplantation development. To date, all feral and laboratory strains of Mus musculus and even Asian species such as Mus cervicolor and Mus pahari express the particles during the 2-8 cell stages. IAP form by budding into the endoplasmic reticulum and appear singly or as groups of donut-shaped particles within the cisternae (fig. 1). IAP are also produced in large numbers in several neoplastic cells such as certain plasmacytomas and rhabdomyosarcomas. The role of IAP, either in normal development or in neoplastic behavior, is unknown.

scholarly journals Characterizing Highly Benefited Patients in Randomized Clinical Trials

2017 ◽  
Vol 13 (1) ◽  
Author(s):  
Vivek Charu ◽  
Paul B. Rosenberg ◽  
Lon S. Schneider ◽  
Lea T. Drye ◽  
Lisa Rein ◽  
...  
Keyword(s):  
Randomized Clinical Trials ◽  
Controlled Trial ◽  
New Method ◽  
Usual Model ◽  
Randomized Controlled ◽  
Working Model ◽  
Large Numbers ◽  
High Benefit ◽  
Two Stages

AbstractPhysicians and patients may choose a certain treatment only if it is predicted to have a large effect for the profile of that patient. We consider randomized controlled trials in which the clinical goal is to identify as many patients as possible that can highly benefit from the treatment. This is challenging with large numbers of covariate profiles, first, because the theoretical, exact method is not feasible, and, second, because usual model-based methods typically give incorrect results. Better, more recent methods use a two-stage approach, where a first stage estimates a working model to produce a scalar predictor of the treatment effect for each covariate profile; and a second stage estimates empirically a high-benefit group based on the first-stage predictor. The problem with these methods is that each of the two stages is usually agnostic about the role of the other one in addressing the clinical goal. We propose a method that characterizes highly benefited patients by linking model estimation directly to the particular clinical goal. It is shown that the new method has the following two key properties in comparison with existing approaches: first, the meaning of the solution with regard to the clinical goal is the same, and second, the value of the solution is the best that can be achieved when using the working model as a predictor, even if that model is incorrect. In the Citalopram for Agitation in Alzheimer’s Disease (CitAD) randomized controlled trial, the new method identifies substantially larger groups of highly benefited patients, many of whom are missed by the standard method.

Beta-Blocker Attenuates Cardiotoxicity Related Anthracycline Usage

2021 ◽  
Vol 104 (8) ◽  
pp. 1389-1392
Keyword(s):  
Side Effects ◽  
Cancer Therapy ◽  
Mortality Rate ◽  
Cancer Patients ◽  
Beta Blocker ◽  
The Other ◽  
Large Numbers ◽  
Therapy Effectiveness ◽  
Chemotherapy Agents

To summarize the recent trials and studies of the role of beta-blocker on the treatment for cancer patients treated with anthracycline to decrease morbidity and mortality rate. Good management of cancer will result in large numbers of cancer survivors. On the other hand, cancer therapy also has side effects, one of which is cardiotoxicity. Cardiotoxicity could reduce therapy effectiveness, hence, increase disease progression and mortality rate. Anthracyclines is one of the chemotherapy agents with cardiotoxicity as a side effect. Beta-blocker has the ability to reduce cardiotoxicity due to anthracyclines usage. Keywords: Beta-blocker; Cardiotoxicity; Anthracyclines

Protozoa abundance, growth, and bacterivory in the water column, on sedimenting particles, and in the sediment of Halifax Harbor

1990 ◽  
Vol 36 (12) ◽  
pp. 859-863 ◽  
Author(s):  
James A. Novitsky
Keyword(s):  
Bacterial Community ◽  
Water Column ◽  
Sediment Surface ◽  
Metabolic Inhibitor ◽  
Optimum Conditions ◽  
Bacterial Populations ◽  
Protozoan Grazing ◽  
Large Numbers ◽  
Doubling Times

The role of protozoan grazing in controlling bacterial populations was examined in four microbial habitats in Halifax Harbor, Canada: the water column, setting particles, the sediment–water interface, and the sediment. Large numbers of protozoans were found in all habitats although most (>56%) were small (<5 μm) flagellates. Protozoans larger than 10 μm were rarely observed; protozoans >20 μm were never observed. Protozoans were also observed to a depth of 9 cm below the sediment surface although efforts to culture viable protozoa failed except for the top 1 cm. The use of the metabolic inhibitor cycloheximide with and without colchicine to selectively inhibit eucaryotic metabolism was shown to severely affect procaryotic metabolism in sediment (and presumably particle and water) samples. Using fluorescently labelled bacteria as food, and under optimum conditions, up to 42% of the Protozoa population exhibited active grazing within 7 h. Using protozoan and bacterial community sizes and doubling times, it was calculated that each protozoan in Halifax Harbor would have to consume 13–118 bacteria per hour for the enumerated nanoplanktonic (<20 μm) Protozoa to be the sole control of the size of the bacterial community. Key words: marine, Protozoa, bacterivory, particles, bacteria.

Illness and Mortality

2017 ◽  
Author(s):  
Golfo Alexopoulos
Keyword(s):  
Health Data ◽  
Large Numbers ◽  
Reported Health

This chapter discusses the role of the Gulag medical-sanitation department. Their task was not necessarily to keep prisoners healthy, but to maximize exploitation and minimize “labor losses.” The Gulag routinely reported health data under the heading “illness and lost labor.” Inmate health was only relevant as it impacted production. The Stalinist leadership established quotas on illnesses and deaths, and would not tolerate large numbers of non-working prisoners. The Stalinist leadership called this “labor therapy,” and believed in work as the key to convalescence. Although sickness, emaciation, and disability were widespread, Gulag officials concealed their existence. In the Gulag, illness was widespread, yet it remained largely untreated, concealed, and even criminalized.

scholarly journals “I’m not an investigator and I’m not a police officer" - a faculty’s view on academic integrity in an undergraduate nursing degree

2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Joan Lynch ◽  
Yenna Salamonson ◽  
Paul Glew ◽  
Lucie M. Ramjan
Keyword(s):  
Nursing Education ◽  
Nursing Faculty ◽  
Academic Integrity ◽  
Codes Of Conduct ◽  
Learning Needs ◽  
Policy And Practice ◽  
Undergraduate Nursing ◽  
Large Numbers ◽  
Academic Integrity Policy

AbstractIn nursing, expectations of honesty and integrity are clearly stipulated throughout professional standards and codes of conduct, thus the concept of academic integrity has even more impetus in preparing students for graduate practice. However, a disparity between policy and practice misses the opportunity to instil the principles of academic integrity, and at its core honesty, a pivotal trait in the nursing profession. This study draws upon the experience of the nursing faculty to explore how academic integrity policy of deterrence operate in nursing education.While participants deplored cheating behaviours, they expressed frustration in having to ‘police’ large numbers of students who had little awareness of the academic standards to meet policy requirements. In addition, they were cynical because of a perceived lack of severity in sanctions for students who repeatedly breached integrity. Participants expressed a moral obligation as educators to meet student learning needs and preferred to engage with students in a more meaningful way to uphold academic integrity. The ambivalence to detect and report breaches in integrity undermines the effectiveness of policy. Therefore, faculty must recognise the importance of their role in detecting and escalating cases of dishonesty and execute deterrence in a more consistent way. To do this, greater support at an institutional level, such as smaller class sizes, inclusion in decision making around sanctions and recognition of additional workload, will enable faculty to uphold policy. Although policing was not their preferred approach, the role of faculty in detecting and reporting cases of misconduct is crucial to increase the certainty of students getting caught, which is essential if policy is to be effective in deterring dishonest behaviour.

Willows in the environment

1992 ◽  
Vol 98 ◽  
pp. 215-224 ◽  
Author(s):  
Alastair H. C. Sommerville
Keyword(s):  
Plant Communities ◽  
Ecological Role ◽  
Large Numbers ◽  
Wide Range

SynopsisThe ecological role of native willows is described in terms of the diverse structure of the species involved, the wide range of plant communities they form and the large numbers of invertebrates associated with them. The conservation importance of the genusSalixis discussed along with comments on the necessary management to retain willow habitats.

scholarly journals A ROLE OF POLYMORPHONUCLEAR LEUKOCYTES AND COMPLEMENT IN NEPHROTOXIC NEPHRITIS

1965 ◽  
Vol 122 (1) ◽  
pp. 99-116 ◽  
Author(s):  
Charles G. Cochrane ◽  
Emil R. Unanue ◽  
Frank J. Dixon
Keyword(s):  
Polymorphonuclear Leukocytes ◽  
Basement Membranes ◽  
Ultrastructural Changes ◽  
Glomerular Injury ◽  
Large Numbers ◽  
Secondary Stage ◽  
Vascular Beds ◽  
Nephrotoxic Nephritis ◽  
Glomerular Damage

In acute nephrotoxic nephritis, polymorphonuclear leukocytes (polymorphs) accumulated in large numbers in the glomeruli in the first 12 hours. The endothelial cells were dislodged by the polymorphs which then came to lie immediately adjacent to the glomerular basement membranes. Ultrastructural changes in neither polymorphs nor basement membranes were observed. Depletion of polymorphs in both rats and rabbits prevented the development of proteinuria. This occurred when doses of nephrotoxic globulin were employed that produced proteinurias of as much as 1800 mg/kg/24 hours in intact rabbits, or enough to yield near maximal immediate proteinuria in intact rats. In addition, measurable glomerular damage was frequently averted until the onset of the secondary stage of NTN. Controls indicated that the polymorph depleted animals exhibited minimal non-specific changes in the blood, that the ability of their vascular beds to react to stimuli was not affected, and that deposition of nephrotoxic antibody and C' in the glomeruli was not inhibited. Elimination of polymorphs from the circulation was only partially effective in preventing glomerular damage when large doses of nephrotoxic globulin were used. This indicated that under these circumstances, a polymorph independent glomerular injury may also take place in first stage nephrotoxic nephritis. An indirect role of C', i.e., the accumulation of polymorphs, in bringing about glomerular injury in first stage nephrotoxic nephritis was apparent. When rabbit nephrotoxic globulin was injected into rats depleted of C', or when duck nephrotoxic globulin that fixed C' poorly was injected into normal rats, C' failed to bind with the antibody along glomerular basement membranes and polymorphs did not accumulate.

Radioproteomics in patients with ovarian cancer

2021 ◽  
pp. 20201331
Author(s):  
Cathal McCague ◽  
Lucian Beer
Keyword(s):  
Ovarian Cancer ◽  
Cancer Progression ◽  
Metabolic Regulation ◽  
Genomic Analysis ◽  
Molecular Profile ◽  
Empirical Knowledge ◽  
Serous Ovarian Carcinoma ◽  
Large Numbers ◽  
Future Direction

Radioproteomics is the integration of proteomics, the systematic study of the protein expression of an organism, with radiomics, the extraction and analysis of large numbers of quantitative features from medical images. This article examines this developing field, and it’s application in high grade serous ovarian carcinoma. Seminal proteomic studies in the area of ovarian cancer, such as the PROVAR and CPTA studies are discussed, along side recent research, such as that highlighting the central role of methyltransferase nicotinamide N-methyltransferase as the metabolic regulation of cancer progression in the tumour stroma. Finally, this article considers a novel, hypothesis generating approach to integrate CT-based qualitative and radiomic features with proteomic analysis, and the future direction of the field. Combined advances in radiomic, proteomic and genomic analysis has the potential to signal the age of true precision medicine, where treatment is centered specifically on the molecular profile of the tumour, rather than based on empirical knowledge, thus altering the course of a disease that has the highest mortality of all cancers of the female reproductive system.

Receiving Mass Casualties at Sea: The Capabilities of the Primary Casualty Receiving Facility

2004 ◽  
Vol 90 (2) ◽  
pp. 51-56
Author(s):  
G. W. L. Evans
Keyword(s):  
United States ◽  
The United States ◽  
Mass Casualties ◽  
Large Numbers ◽  
Eastern Seaboard

AbstractExercise Aurora (May-June 2004) off the eastern Seaboard of the United States provided an opportunity, on several occasions, to test the ability of the PCRF to cope with large numbers of “casualties” arriving simultaneously. This article reviews the role of the PCRF, its facilities and capabilities, and how these are currently utilised to handle mass casualties. Some of the valuable lessons identified from Exercise Aurora are briefly discussed.

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