The development and overwintering survival of free-living larvae of Haemonchus contortus in Sweden

2005 ◽  
Vol 79 (4) ◽  
pp. 373-379 ◽  
Author(s):  
K. Troell ◽  
P. Waller ◽  
J. Höglund
Keyword(s):  
Haemonchus Contortus ◽  
Practical Significance ◽  
Southern Sweden ◽  
Free Living ◽  
Term Survival ◽  
Commercial Flock ◽  
Long Time ◽  
Overwintering Survival ◽  
Eggs And Larvae

AbstractFive complimentary studies were undertaken with the overall aim to examine the ability of free-living stages of Haemonchus contortus to over-winter and tolerate cold stress. Two studies deal with the development and long-term survival of eggs and infective larvae of two geographically different isolates (Kenya and Sweden). Eggs and larvae were monitored in climatic chambers at temperatures that fluctuated daily between −1°C and 15°C, or at constant temperatures of 5°C and 15°C. The development from egg to larvae was dependent on temperatures over 5°C. The long time survival was favoured at lower temperatures. Furthermore, the overwintering capacity of the free-living stages of these isolates was estimated under Swedish field conditions. Two groups of lambs were experimentally infected with different isolates, and kept separated on previously ungrazed plots. In early May the following year, two parasite-naive tracer lambs were turned out on each of the plots to estimate the pick up of overwintered larvae. This experiment was replicated in central and southern Sweden. In addition, two experiments were performed in 2003 on pasture previously grazed by naturally infected sheep. One trial was on a pasture in southern Sweden grazed by a commercial flock, where extreme numbers of H. contortus were found towards the end of the grazing season 2002. The other study was on a pasture plot in central Sweden grazed by a hobby flock in 2002, where three of six lambs died due to haemonchiasis. Overwintered H. contortus was recorded on three of four experimental sites. Worm burdens were in all instances extremely low. No differences in development and survival were found between the isolates. Consequently, overwintering on pasture is of no practical significance in the transmission of H. contortus between grazing-seasons in Sweden.

Observations on the free-living stages of the stomach worm Haemonchus contortus

Parasitology ◽  
1963 ◽  
Vol 53 (3-4) ◽  
pp. 469-481 ◽  
Author(s):  
J. H. Rose
Keyword(s):  
Haemonchus Contortus ◽  
Free Living ◽  
Rate Of Development ◽  
Temperature And Humidity ◽  
Survival And Development ◽  
Effects Of Temperature ◽  
Eggs And Larvae ◽  
Heavy Mortality

Outdoor observations were made on the rate of development of the free-living stages of H. contortus at different times of the year, and on the migratory activities and longevity of the larvae in faeces, on herbage and in soil.The effects of temperature and humidity on the survival and development of eggs and larvae, both in faeces and when separated from the faeces, were studied in the laboratory.The results of these observations are discussed in relation to the heavy mortality of the free-living stages of H. contortus and to the transmission of infection in the field.

scholarly journals Long-Term Survival in a Patient with Pulmonary Lymphangioleiomyomatosis

2002 ◽  
Vol 9 (5) ◽  
pp. 342-346 ◽  
Author(s):  
John K Reid ◽  
Henrike Rees ◽  
Donald Cockcroft
Keyword(s):  
High Resolution ◽  
Lung Function ◽  
Symptom Onset ◽  
Exercise Tolerance ◽  
Lung Biopsy ◽  
Term Survival ◽  
Pulmonary Lymphangioleiomyomatosis ◽  
Long Time ◽  
Minimal Reduction

A patient with pulmonary lymphangioleiomyomatosis was diagnosed more than 22 years after the onset of symptoms by a thoracoscopic lung biopsy, after a high resolution computerized tomogram of the chest was highly suggestive of the disease. After nearly 30 years since the onset of her symptoms, the patient leads a relatively normal life with only mildly abnormal lung function and has minimal reduction in her exercise tolerance. There have been few reports of patients surviving for such a long time after the onset of this disease; the literature suggests that most patients die within 15 years of symptom onset.

scholarly journals Changes in Barotolerance, Thermotolerance, and Cellular Morphology throughout the Life Cycle of Listeria monocytogenes

2009 ◽  
Vol 75 (6) ◽  
pp. 1581-1588 ◽  
Author(s):  
Jia Wen ◽  
Ramaswamy C. Anantheswaran ◽  
Stephen J. Knabel
Keyword(s):  
Heat Treatment ◽  
Life Cycle ◽  
Listeria Monocytogenes ◽  
Cellular Morphology ◽  
Practical Significance ◽  
Term Survival ◽  
Long Term Survival ◽  
Whole Milk ◽  
Thermally Processed

ABSTRACT Changes in barotolerance, thermotolerance, and cellular morphology throughout the life cycle of Listeria monocytogenes were investigated. For part 1 of this analysis, L. monocytogenes ATCC 19115 was grown to log, stationary, death, and long-term-survival phases at 35°C in tryptic soy broth with yeast extract (TSBYE). Cells were diluted in whole milk that had been subjected to ultrahigh temperatures (UHT whole milk) and then high-pressure processed (HPP) at 400 MPa for 180 s or thermally processed at 62.8°C for 30 s. As cells transitioned from the log to the long-term-survival phase, the D400 MPa and D62.8°C values increased 10- and 19-fold, respectively. Cells decreased in size as they transitioned from the log to the long-term-survival phase. Rod-shaped cells transitioned to cocci as they entered the late-death and long-term-survival phases. L. monocytogenes strains F5069 and Scott A showed similar results. For part 2 of the analysis, cells in long-term-survival phase were centrifuged, suspended in fresh TSBYE, and incubated at 35°C. As cells transitioned from the long-term-survival phase to log and the stationary phase, they increased in size and log reductions increased following HPP or heat treatment. In part 3 of this analysis, cells in long-term-survival phase were centrifuged, suspended in UHT whole milk, and incubated at 4°C. After HPP or heat treatment, similar results were observed as for part 2. We hypothesize that cells of L. monocytogenes enter a dormant, long-term-survival phase and become more barotolerant and thermotolerant due to cytoplasmic condensation when they transition from rods to cocci. Further research is needed to test this hypothesis and to determine the practical significance of these findings.

scholarly journals Analysis of the relationship between corporate identity, image and reputation of the company

Tehnika ◽  
2021 ◽  
Vol 76 (4) ◽  
pp. 499-505
Author(s):  
Milovan Vuković ◽  
Aleksandra Vuković ◽  
Ivana Mladenović-Ranisavljević ◽  
Snežana Urošević
Keyword(s):  
Corporate Reputation ◽  
Relevant Literature ◽  
Corporate Identity ◽  
Corporate Image ◽  
Economic Downturn ◽  
Competitive Advantages ◽  
Term Survival ◽  
Whole Process ◽  
Long Time

For a long time, corporate identity, corporate image and corporate reputation have been studied from a number of academic perspectives, due to their intangibility and their significant role in gaining an organization's competitive advantages. Recent business circumstances (for example, the economic downturn due to the Covid-19 pandemy) bring new challenges for companies and their long-term survival. The aim of this paper is to review the constructs of corporate identity, corporate image and corporate reputation, and, thus, to remove or reduce the misunderstanding of the three constructs in the relevant literature. After a thorough theoretical review, some influential conceptual models were examined, pointing out the role of communication in the whole process of corporate marketing.

scholarly journals Long-Term Survival of Shiga Toxin-ProducingEscherichia coli O26, O111, and O157 in Bovine Feces

1999 ◽  
Vol 65 (11) ◽  
pp. 5177-5181 ◽  
Author(s):  
Hiroshi Fukushima ◽  
Ken Hoshina ◽  
Manabu Gomyoda
Keyword(s):  
Escherichia Coli ◽  
Shiga Toxin ◽  
Term Survival ◽  
Long Term Survival ◽  
Low Concentration ◽  
Long Time ◽  
High Concentrations ◽  
Bovine Feces

ABSTRACT Cattle are an important reservoir of Shiga toxin-producingEscherichia coli (STEC) O26, O111, and O157. The fate of these pathogens in bovine feces at 5, 15, and 25°C was examined. The feces of a cow naturally infected with STEC O26:H11 and two STEC-free cows were studied. STEC O26, O111, and O157 were inoculated into bovine feces at 101, 103, and 105 CFU/g. All three pathogens survived at 5 and 25°C for 1 to 4 weeks and at 15°C for 1 to 8 weeks when inoculated at the low concentration. On samples inoculated with the middle and high concentrations, O26, O111, and O157 survived at 25°C for 3 to 12 weeks, at 15°C for 1 to 18 weeks, and at 5°C for 2 to 14 weeks, respectively. Therefore, these pathogens can survive in feces for a long time, especially at 15°C. The surprising long-term survival of STEC O26, O111, and O157 in bovine feces shows that such feces are a potential vehicle for transmitting not only O157 but also O26 and O111 to cattle, food, and the environment. Appropriate handling of bovine feces is emphasized.

scholarly journals Resource acquisition and allocation traits in symbiotic rhizobia with implications for life-history outside of legume hosts

2018 ◽  
Vol 5 (12) ◽  
pp. 181124 ◽  
Author(s):  
Katherine E. Muller ◽  
R. Ford Denison
Keyword(s):  
Root Nodules ◽  
Natural Populations ◽  
Heritable Variation ◽  
Free Living ◽  
Term Survival ◽  
Individual Level ◽  
Dividing Cells ◽  
Term Functions ◽  
Microbial Symbionts

Resources that microbial symbionts obtain from hosts may enhance fitness during free-living stages when resources are comparatively scarce. For rhizobia in legume root nodules, diverting resources from nitrogen fixation to polyhydroxybutyrate (PHB) has been discussed as a source of host–symbiont conflict. Yet, little is known about natural variation in PHB storage and its implications for rhizobial evolution. We therefore measured phenotypic variation in natural rhizobia populations and investigated how PHB might contribute to fitness in the free-living stage. We found that natural populations of rhizobia from Glycine max and Chamaecrista fasciculata had substantial, heritable variation in PHB acquisition during symbiosis. A model simulating temperature-dependent metabolic activity showed that the observed range of stored PHB per cell could support survival for a few days, for active cells, or over a century for sufficiently dormant cells. Experiments with field-isolated Bradyrhizobium in starvation culture suggest PHB is partitioned asymmetrically in dividing cells, consistent with individual-level bet-hedging previously demonstrated in E. meliloti . High-PHB isolates used more PHB over the first month, yet still retained more PHB for potential long-term survival in a dormant state. These results suggest that stored resources like PHB may support both short-term and long-term functions that contribute to fitness in the free-living stage.

scholarly journals Temozolomide and Radiotherapy versus Radiotherapy Alone in High Grade Gliomas: A Very Long Term Comparative Study and Literature Review

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Salvatore Parisi ◽  
Pietro Corsa ◽  
Arcangela Raguso ◽  
Antonio Perrone ◽  
Sabrina Cossa ◽  
...  
Keyword(s):  
Combined Treatment ◽  
Haematological Toxicity ◽  
High Grade ◽  
Term Survival ◽  
Long Time ◽  
Radiotherapy Alone ◽  
High Grade Gliomas ◽  
Time Basis ◽  
Grade 3

Temozolomide (TMZ) is the first line drug in the care of high grade gliomas. The combined treatment of TMZ plus radiotherapy is more effective in the care of brain gliomas then radiotherapy alone. Aim of this report is a survival comparison, on a long time (>10 years) span, of glioma patients treated with radiotherapy alone and with radiotherapy + TMZ.Materials and Methods. In this report we retrospectively reviewed the outcome of 128 consecutive pts with diagnosis of high grade gliomas referred to our institutions from April 1994 to November 2001. The first 64 pts were treated with RT alone and the other 64 with a combination of RT and adjuvant or concomitant TMZ.Results. Grade 3 (G3) haematological toxicity was recorded in 6 (9%) of 64 pts treated with RT and TMZ. No G4 haematological toxicity was observed. Age, histology, and administration of TMZ were statistically significant prognostic factors associated with 2 years overall survival (OS). PFS was for GBM 9 months, for AA 11.Conclusions. The combination of RT and TMZ improves long term survival in glioma patients. Our results confirm the superiority of the combination on a long time basis.

scholarly journals Feeding behaviour and pugmark analysis of elephants in Sarguja, Chhattisgarh

2016 ◽  
Vol 8 (4) ◽  
pp. 2060-2065 ◽  
Author(s):  
A. K. Thakur ◽  
D. K. Yadav ◽  
M. K. Jhariya
Keyword(s):  
Cynodon Dactylon ◽  
Crop Raiding ◽  
Aegle Marmelos ◽  
Forest Department ◽  
Term Survival ◽  
Dendrocalamus Strictus ◽  
Long Time ◽  
Four Blocks ◽  
Palatable Species

The pugmark analysis of the elephants offers basic information to track the wild elephant migratory route, identification and census. For its study, four blocks viz, Sitapur, Lundra, Batouli (Sarguja district) and Farsabahar (Jashpur district) of northern Chhattisgarh were selected because these blocks are commonly visited by elephants and a major path route of movement of heard in inter/intra state. The most commonly consumed species belongs to family poaceae (22.58%) followed by fabaceae (19.35%) but their diet was mainly dependent on availability of seasonal food round the year and on their migration. Elephants extensively fed on Artocarpus heterophyllus, Syzygium cumini, Acacia nilotica, A. catechu, Dalbergia sissoo, Zizyphus mauritiana, Aegle marmelos and Ficus species, besides these elephants also utilized various grasses and shrubs as their food, which mainly included Dendrocalamus strictus, Cynodon dactylon etc. Elephants sometimes spent long time to feed on some particular plant species like D. strictus and Ficus species. Crop raiding, which was sporadic during the rainy season, gradually increased with more area being cultivated with the onset of monsoon. Analysis of pugmark revealed that the circumference varied from 63.80 cm to 172.70 cm whereas length x width varied from 22x20 cm to 60x55 cm, which reflects a substantial variation/differentiation of individual in heard in respect of their age, sex, size etcTherefore, management implications are needed to conserve the corridors for their long term survival and reduction of HEC. The study will be helpful to provide key information and facilitate better understating of the scenario to the forest department, policy maker and conservationist to plan, manage and improve the habitat towards the restoration and afforestation of suitable palatable species preferred by elephants of northern corridors of Chhattisgarh.

scholarly journals Effects of Salinity and Temperature on Long-Term Survival of the Eel Pathogen Vibrio vulnificus Biotype 2 (Serovar E)

1999 ◽  
Vol 65 (3) ◽  
pp. 1117-1126 ◽  
Author(s):  
Ester Marco-Noales ◽  
Elena G. Biosca ◽  
Carmen Amaro
Keyword(s):  
Aquatic Ecosystem ◽  
Vibrio Vulnificus ◽  
Membrane Vesicles ◽  
Extracellular Material ◽  
Free Living ◽  
Term Survival ◽  
Optimal Salinity ◽  
Long Term Survival ◽  
Cellular Lysis

ABSTRACT Vibrio vulnificus biotype 2 (serovar E) is a primary eel pathogen. In this study, we performed long-term survival experiments to investigate whether the aquatic ecosystem can be a reservoir for this bacterium. We have used microcosms containing water of different salinities (ranging from 0.3 to 3.8%) maintained at three temperatures (12, 25, and 30°C). Temperature and salinity significantly affected long-term survival: (i) the optimal salinity for survival was 1.5%; (ii) lower salinities reduced survival, although they were nonlethal; and (ii) the optimal temperature for survival was dependent on the salinity (25°C for microcosms at 0.3 and 0.5% and 12°C for microcosms at 1.5 to 3.8%). In the absence of salts, culturability dropped to zero in a few days, without evidence of cellular lysis. Under optimal conditions of salinity and temperature, the bacterium was able to survive in the free-living form for at least 3 years. The presence of a capsule on the bacterial cell seemed to confer an advantage, since the long-term survival rate of opaque variants was significantly higher than that of translucent ones. Long-term-starved cells maintained their infectivity for eels (as determined by both intraperitoneal and immersion challenges) and mice. Examination under the microscope showed that (i) the capsule was maintained, (ii) the cell size decreased, (iii) the rod shape changed to coccuslike along the time of starvation, and (iv) membrane vesicles and extracellular material were occasionally produced. In conclusion, V. vulnificus biotype 2 follows a survival strategy similar to that of biotype 1 of this species in response to starvation conditions in water. Moreover, the aquatic ecosystem is one of its reservoirs.

scholarly journals A Combination of Systemic and Intracranial Anti-CD25 Immunotherapy Elicits a Long-Time Survival in Murine Model of Glioma

2009 ◽  
Vol 2009 ◽  
pp. 1-8 ◽  
Author(s):  
Marie-Denise Poirier ◽  
Houda Haban ◽  
Abdeljabar El Andaloussi
Keyword(s):  
Immune Response ◽  
Antitumor Immune Response ◽  
Term Survival ◽  
Long Term Survival ◽  
Long Time ◽  
The Central Nervous System ◽  
The Brain ◽  
Gl261 Glioma ◽  
New Strategies

Abrogating the suppression of glioma-infiltrating Tregs in the periphery and the central nervous system is essential to successful glioma rejection. We sought to improve the immune response in glioma-bearing mice, by investigating new strategies using the anti-CD25 immunotherapy. We found a complete long-term survival of glioma-bearing mice treated with a combination of systemic and intracranial anti-CD25 mAb immunotherapy as compared to systemic administration of anti-CD25 mAb. In addition, the group of mice that had been cured by the combined anti-CD25 mAb showed long-term survival without late tumor relapse when challenged with the GL261 glioma. The antitumor immune response was investigated by analysis of antitumor immune response (CTL). Results showed that the use of the combined injections of anti-CD25 mAb induced efficient targeting of Tregs expansion inside and outside of the brain and altered Tregs trafficking in the bone marrow and brain areas where antitumor immunity was primed.

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