scholarly journals Nematospiroides dubius in the jird, Meriones unguiculatus: factors affecting the course of a primary infection

1982 ◽  
Vol 56 (4) ◽  
pp. 329-338 ◽  
Author(s):  
John Hannah ◽  
Jerzy M. Behnke
Keyword(s):  
Primary Infection ◽  
Meriones Unguiculatus ◽  
Baseline Data ◽  
Factors Affecting ◽  
Low Level ◽  
Susceptibility To Infection ◽  
Infective Larvae ◽  
Nematospiroides Dubius ◽  
Future Work ◽  
Age And Sex

ABSTRACTThis project investigated the influence of the age and sex of the host and the level of infection with Nematospiroides dubius on the establishment and duration of a primary infection in the jird. It was found that 30 to 35% fewer worms matured in jirds than in mice and that this proportion was unaffected by the level of infection or by the sex of the host. In contrast the age of the jird was found to be critically important in determining the number of adult worms recovered 14 days after infection. Thus, maximum susceptibility to infection was observed when jirds were 18 to 22 days old. In older jirds susceptibility declined until 30 days after birth and thereafter, when approximately 70% of the infective larvae matured (relative to the number of worms maturing in mice).The duration of a primary infection in jirds was similar in both sexes but was influenced by the level of infection and by the age of the host at infection. Heavier infections (500 larvae) lasted about 10 days longer than low level infections, and expulsion of the parasite occurred even when the host was infected with only five larvae. The duration of a primary infection was markedly prolonged in neonatal jirds, faecal egg counts remaining positive for 54 to 56 days after infection of 12-day-old jirds.These results supply some further baseline data for future work on the biology of N. dubius in the jird and they provide support for the involvement of immunological processes in the termination of primary infections of this parasite in mature jirds.

scholarly journals The effect of gamma irradiation on Nematospiroides dubius. Factors affecting the survival of worms in a primary infection in mice

1980 ◽  
Vol 54 (3) ◽  
pp. 173-182 ◽  
Author(s):  
Jerzy M. Behnke ◽  
Heather A. Parish ◽  
Paul Hagan
Keyword(s):  
Gamma Irradiation ◽  
Primary Infection ◽  
Survival Curve ◽  
Low Doses ◽  
Factors Affecting ◽  
Infective Larvae ◽  
Logarithmic Plot ◽  
Nematospiroides Dubius ◽  
Sublethal Irradiation

ABSTRACTThe infective larvae of Nematospiroides dubius were exposed to various levels (0–30 krad) of gamma irradiation by means of a Cobalt 60 source. Groups of mice were infected with these larvae and autopsied 5 weeks later for worm counts. It was found that male worms were more susceptible to irradiation than female worms. In both instances, however, the survival curve on a semi logarithmic plot was characterised by a shoulder at low doses and an exponential component at the higher levels of exposure. No male worms were recovered from mice infected with larvae given more than 12 krad but some female worms were capable of surviving 20 krad. The fecundity of female worms was reduced by 61% at 4 krad and totally ablated at 8 krad.Further experiments demonstrated that the survival of irradiated N. dubius in vivo was related to the extent of the damage caused at the time of irradiation and was not dependant on additional host parameters. Thus neither the number of irradiated worms inoculated nor the sex of the host radically altered the sex ratio or proportion of the worms lost as a result of irradiating the larvae. Furthermore, treatment with cortisone or sublethal irradiation of the host did not increase the proportion of surviving worms. It was, therefore, concluded that a host immune response was not involved.

scholarly journals Nematospiroides dubius: factors affecting the primary response to SRBC in infected mice

1983 ◽  
Vol 57 (4) ◽  
pp. 343-353 ◽  
Author(s):  
Najah M. H. Ali ◽  
Jerzy M. Behnke
Keyword(s):  
Critical Period ◽  
Severe Depression ◽  
Primary Response ◽  
Factors Affecting ◽  
Low Level ◽  
Nematospiroides Dubius ◽  
Loss Of Appetite ◽  
Host Immunocompetence

AbstractMice infected with Nematospiroides dubius were incapable of responding normally to i.p. or i.v. challenge with SRBC. The HA and PFC response to SRBC in infected animals was characterized by a severe depression of antibody to SRBC on day 4 and a reduced HA peak titre during the following week. The greatest depression of the response to SRBC was associated with an interval of 14 days between infection and the administration of antigen, suggesting that a particular stage of the parasite contributed significantly to immunodepression during this critical period. It was proposed that a combination of parasite induced damage to the intestine, release of parasite secretory/excretory products and loss of appetite by the host produced trauma during which the host was incapable of responding normally.However, mice given low-level and long-standing infections also showed reduced responses to SRBC, although these animals were not severely depressed. It is possible that this generalized weakening of host immunocompetence is the inevitable consequence of a parasite mechanism which operates more specifically to suppress the expression of homologous immunity at the intestinal level.

scholarly journals GENETIC LINKAGE IN THE HORSE. II. DISTRIBUTION OF MALE RECOMBINATION ESTIMATES AND THE INFLUENCE OF AGE, BREED AND SEX ON RECOMBINATION FREQUENCY

Genetics ◽  
1984 ◽  
Vol 106 (1) ◽  
pp. 109-122
Author(s):  
Leif Andersson ◽  
Kaj Sandberg
Keyword(s):  
Genetic Linkage ◽  
Recombination Frequency ◽  
Age Effect ◽  
Significant Heterogeneity ◽  
Male Recombination ◽  
Male And Female ◽  
Factors Affecting ◽  
Individual Male ◽  
Breed Differences ◽  
Age And Sex

ABSTRACT n the present study an extensive amount of data, comprising more than 30,000 offspring in total, was analyzed to evaluate the influence of age and sex on the recombination frequency in the K-PGD segment of the equine linkage group (LG) I and the influence of age, breed and sex on recombination in the Al-Es segment of LG II. A highly significant sex difference is reported for both segments. Male and female recombination values in the K-PGD segment were estimated at 25.8 ± 0.8 and 33.3 ± 2.5%, respectively. Similarly, recombination was less frequent in the male (36.6 ± 0.7%) than in the female (46.6 ± 1.2%) in the Al-Es segment. Comparison of data from two Swedish horse breeds revealed no significant breed differences in either sex for recombination in the Al-Es segment. No evidence of an age effect was found in any segment or sex. The distribution of individual male recombination estimates was also investigated, and a significant heterogeneity among stallions was revealed in the K-PGD segment. The results are discussed in relation to previous studies on factors affecting recombination in mammals.

Temporal and regional variations in sporadic Creutzfeldt–Jakob disease in Japan, 2001–2010

2014 ◽  
Vol 143 (5) ◽  
pp. 1073-1078 ◽  
Author(s):  
E. NAKATANI ◽  
T. NISHIMURA ◽  
B. ZHOU ◽  
H. KANEDA ◽  
S. TERAMUKAI ◽  
...  
Keyword(s):  
Clustering Analysis ◽  
National Average ◽  
National Surveillance ◽  
Regional Variations ◽  
Factors Affecting ◽  
Disease Clustering ◽  
Average Annual Incidence ◽  
Jakob Disease ◽  
Specific Factors ◽  
Age And Sex

SUMMARYThe objective of this study was to examine temporal and regional variations of sporadic Creutzfeldt–Jakob disease (sCJD) in a retrospective study using Japanese national surveillance data from 2001 to 2010. We calculated the incidence of sCJD by age and sex, derived the standardized incidence in each of the 47 prefectures, and performed spatial disease clustering analysis. The average annual incidence of sCJD was 1·026 per million in men (637 patients) and 1·132 per million in women (733 patients), a significant sex difference after adjustment for age (P = 0·001). The ratios of familial CJD to sCJD apparently increased between 2001–2005 and 2006–2010, possibly as a result of the nationwide introduction of genetic testing after 2006. Based on the data of 2006–2010, certain geographical clusters of sCJD were identified. The incidence of sCJD was higher in several specific prefectures compared to the national average. Thus, sCJD appears to have regional variations, suggesting the existence of genetic or region-specific factors affecting the incidence of the disease.

Factors affecting the acceptability of grammatical features of Hong Kong English

English Today ◽  
2018 ◽  
Vol 35 (2) ◽  
pp. 29-35 ◽  
Author(s):  
Shawnea Sum Pok Ting ◽  
Janice Wing Sze Wong
Keyword(s):  
Hong Kong ◽  
Local Features ◽  
Factors Affecting ◽  
Local Variety ◽  
Low Level ◽  
Independent Varieties ◽  
Hong Kong English ◽  
The City

Although a large number of varieties of English in Asia have gained recognition as independent varieties, this has not been the case for Hong Kong English (HKE) (Jenkins, 2015: 162). The city has a low level of affiliation towards HKE (Jenkins, 2015: 167) and often laments its ever-falling standard of English (Leung, 2015). There exists a phenomenon of ‘linguistic schizophrenia’ – the community may recognise that a local variety of English exists and conform to its features in practice, but it still looks to native varieties as the norm and views local features as evidence of deteriorating language standards (Kachru, 1983: 118).

Age- and sex-related morphological and physiological differences influence escape capacity in House Sparrows (Passer domesticus)

2010 ◽  
Vol 88 (10) ◽  
pp. 1021-1031 ◽  
Author(s):  
L. De Neve ◽  
J. D. Ibañez-Alamo ◽  
M. Soler
Keyword(s):  
Escape Response ◽  
Passer Domesticus ◽  
First Year ◽  
Cell Mediated Immunity ◽  
Animal Performance ◽  
House Sparrows ◽  
Factors Affecting ◽  
Age Related ◽  
Animal Populations ◽  
Age And Sex

Sexual dimorphism and age-related differences are sources that contribute to morphologic and physiologic variation within animal populations. Measurement of animal performance may indicate whether this variation is functionally relevant. Our study aimed to experimentally test this statement in a captive population of House Sparrows ( Passer domesticus (L., 1758)) by examining age- and sex-related differences in escape response and its relationship to several morphological (tarsus, wing, tail lengths, and body mass) and physiological traits (cell-mediated immunity, natural antibodies, complement activity, hematocrit, and stress response). Escape response from a predator is considered a good variable to measure animal performance, because natural selection clearly favours individuals that avoid predators successfully. Our experimental design also aimed to standardize possible confounding factors affecting escape behaviour under natural conditions. We exposed sparrows to short episodes of high predation risk by simulating the attack of a predator and assumed that the capture order of individuals was related to their escape capacity. The optimal strategy was the immediate escape response for all individuals. We found that first-year males were the best escapers. In support of the hypothesis, juvenile males gathered a better optimum of several morphological and physiological characters that related to capture order.

Attempted vaccination of jirds (Meriones unguiculatus) againstBrugia pahangiwith radiation attenuated infective larvae

1986 ◽  
Vol 60 (2) ◽  
pp. 149-155 ◽  
Author(s):  
W. Chusattayanond ◽  
D. A. Denham
Keyword(s):  
Meriones Unguiculatus ◽  
Brugia Pahangi ◽  
Infective Larvae

ABSTRACTJirds were vaccinated by three to five subcutaneous (SC) injections of infective larvae ofBrugia pahangiwhich had been irradiated at 25, 45 or 90 krads from a60Co source. They were challenged either SC or intraperitoneally. Vaccination with four doses of 50 larvae irradiated with 25 krads produced 49·3% resistance to IP challenge worms and 39·8% against SC challenge worms. Five doses of larvae irradiated with 45 krads produced 62% resistance to SC challenge. Three doses of larvae irradiated with 90 krads produced 74·9% resistance to SC challenge and five doses produced 76·2% resistance. The reasons why irradiated larvae produce resistance whereas normal larvae do not are discussed.

scholarly journals Reducing Alert Fatigue by Sharing Low-Level Alerts With Patients and Enhancing Collaborative Decision Making Using Blockchain Technology: Scoping Review and Proposed Framework (MedAlert) (Preprint)

2020 ◽  
Author(s):  
Paul Kengfai Wan ◽  
Abylay Satybaldy ◽  
Lizhen Huang ◽  
Halvor Holtskog ◽  
Mariusz Nowostawski
Keyword(s):  
Health Care ◽  
Decision Making ◽  
Scoping Review ◽  
Health Care Quality ◽  
Research Question ◽  
Clinical Decision ◽  
Care Quality ◽  
Alert Fatigue ◽  
Low Level ◽  
Future Work

BACKGROUND Clinical decision support (CDS) is a tool that helps clinicians in decision making by generating clinical alerts to supplement their previous knowledge and experience. However, CDS generates a high volume of irrelevant alerts, resulting in alert fatigue among clinicians. Alert fatigue is the mental state of alerts consuming too much time and mental energy, which often results in relevant alerts being overridden unjustifiably, along with clinically irrelevant ones. Consequently, clinicians become less responsive to important alerts, which opens the door to medication errors. OBJECTIVE This study aims to explore how a blockchain-based solution can reduce alert fatigue through collaborative alert sharing in the health sector, thus improving overall health care quality for both patients and clinicians. METHODS We have designed a 4-step approach to answer this research question. First, we identified five potential challenges based on the published literature through a scoping review. Second, a framework is designed to reduce alert fatigue by addressing the identified challenges with different digital components. Third, an evaluation is made by comparing MedAlert with other proposed solutions. Finally, the limitations and future work are also discussed. RESULTS Of the 341 academic papers collected, 8 were selected and analyzed. MedAlert securely distributes low-level (nonlife-threatening) clinical alerts to patients, enabling a collaborative clinical decision. Among the solutions in our framework, Hyperledger (private permissioned blockchain) and BankID (federated digital identity management) have been selected to overcome challenges such as data integrity, user identity, and privacy issues. CONCLUSIONS MedAlert can reduce alert fatigue by attracting the attention of patients and clinicians, instead of solely reducing the total number of alerts. MedAlert offers other advantages, such as ensuring a higher degree of patient privacy and faster transaction times compared with other frameworks. This framework may not be suitable for elderly patients who are not technology savvy or in-patients. Future work in validating this framework based on real health care scenarios is needed to provide the performance evaluations of MedAlert and thus gain support for the better development of this idea. CLINICALTRIAL

scholarly journals Exploration of Factors Affecting Learners' Motivation in E-learning

2019 ◽  
pp. 1269-1275
Author(s):  
Shubham Dubey ◽  
Biro Piroska ◽  
Manjulata Gautam
Keyword(s):  
Dropping Out ◽  
Individual Factor ◽  
Factors Affecting ◽  
E Learning ◽  
Learning Platforms ◽  
The Common ◽  
Khan Academy ◽  
Future Work ◽  
The Impact

The world is changing rapidly, so is academics. E-learning has altered the area of academics and education. ICT enabled learning has given ideal services to students by providing any type of content on demand which is proportional to the performance of students. The concentration of learner has been found instinctive; thus there is a need of engaging mind towards course progress with its entirety till the objectives of the course will be achieved. There are several e-learning platforms available as EdX, Udacity, Khan Academy, Alison those have a number of learners registered for various courses. Studies suggest that these platforms suffer from the common problem of learners’ dropping out. Investigations also claim early leaving rate is increasing due to lack of quality of content, distraction factors, learners’ mind change, outdated and succinct information, and some more detraction factors. These issues have been observed on the basis of early leaving rates in various MOOCs. Thus there is a mammoth scope for minimizing the impact of these reasons on the learners’ mind. It can be achieved by identifying these factors affecting learners’ motivation during the course. This study is aiming on identifying these factors. The approach is to explore some certain keywords on previous literature (total 41) and then calculating their frequencies and co-factors associated with them. Both grouped factors contribution and individual factor contribution have been taken care. The study gives a direction for future work towards overcoming these actor and engaging learners in ICT enabled learning.

Genetic control of liability to infection with Nematospiroides dubius in mice: direct and correlated responses to selection of mice for faecal parasite egg count

Parasitology ◽  
1983 ◽  
Vol 87 (1) ◽  
pp. 113-127 ◽  
Author(s):  
P. J. Brindley ◽  
C. Dobson
Keyword(s):  
Genetic Control ◽  
Primary Infection ◽  
Genetic Correlations ◽  
Strong Positive Correlation ◽  
Correlated Responses ◽  
Antibody Titres ◽  
Refractory State ◽  
Selection Limit ◽  
Nematospiroides Dubius ◽  
Positive Correlations

SUMMARYMice selected as liable (L) and refractory (R) over 10 generations voided significantly more and less Nematospiroides dubius eggs compared with randomly mated (Rd) mice after primary infection with 100 larvae. Strong positive correlation was found between the numbers of N. dubius eggs in mouse faeces and the numbers of adult N. dubius recovered from mice culled from the R, Rd and L colonies. Selection limit based on a faecal e.p.g. was reached in the L mice after 9 generations whereas the faecal N. dubius e.p.g. voided by the R mice continued to decline throughout selection. In contrast, no change in worm numbers was found in L or R mice after 6 generations. The refractory state of the trait, liability to infection with N. dubius, was inherited as a dominant character with a realized heritability value of ~ 0∣2. Differential correlated responses from N. dubius infectivity compared with N. dubius fecundity and growth indicated murine genetic control of this trait by 2 major genetic units. In general, there were negative phenotypic and genetic correlations between the faecal N. dubius e.p.g. of mice and murine morphological conformation, but positive correlations between the faecal N. dubius e.p.g. of selected mice and establishment, growth and fecundity of N. dubius populations in these mice. There was little correlation between the faecal N. dubius e.p.g. after primary infection and anti-N. dubius antibody titres and parasite female/male sex-ratio.

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