scholarly journals Assessment of Factors Influencing Direct Enumeration of Viruses within Estuarine Sediments

2006 ◽  
Vol 72 (7) ◽  
pp. 4767-4774 ◽  
Author(s):  
Rebekah R. Helton ◽  
Ling Liu ◽  
K. Eric Wommack

ABSTRACT Accurate enumeration of viruses within environmental samples is critical for investigations of the ecological role of viruses and viral infection within microbial communities. This report evaluates differences in viral and bacterial direct counts between estuarine sediment samples which were either immediately processed onboard ship or frozen at −20°C and later processed. Viral and bacterial abundances were recorded at three stations spanning the length of the Chesapeake Bay in April and June 2003 within three sediment fractions: pore water (PW), whole sediment (WS), and sediment after pore water removal (AP). No significant difference in viral abundance was apparent between extracts from fresh or frozen sediments. In contrast, bacterial abundance was significantly lower in the samples subjected to freezing. Both bacterial and viral abundance showed significant differences between sediment fractions (PW, WS, or AP) regardless of the fresh or frozen status. Although pore water viral abundance has been used in the past as a measurement of viral abundance in sediments, this fraction accounted for only ca. 5% of the total sediment viral abundance across all samples. The effect of refrigerated storage of sediment viral extracts was also examined and showed that, within the first 2 h, viral abundance decreased ca. 30% in formalin-fixed extracts and 66% in unfixed extracts. Finally, the reliability of direct viral enumeration via epifluorescence microscopy was tested by using DNase treatment of WS extractions. These tests indicated that a large fraction (>86%) of the small SYBR gold fluorescing particles are likely viruses.

2004 ◽  
Vol 70 (7) ◽  
pp. 3862-3867 ◽  
Author(s):  
Kevin Wen ◽  
Alice C. Ortmann ◽  
Curtis A. Suttle

ABSTRACT Virus enumeration by epifluorescence microscopy (EFM) is routinely done on preserved, refrigerated samples. Concerns about obtaining accurate and reproducible estimates led us to examine procedures for counting viruses by EFM. Our results indicate that aldehyde fixation results in rapid decreases in viral abundance. By 1 h postfixation, the abundance dropped by 16.4% ± 5.2% (n = 6), and by 4 h, the abundance was 20 to 35% lower. The average loss rates for glutaraldehyde- and formaldehyde-fixed samples over the first 2 h were 0.12 and 0.13 h−1, respectively. By 16 days, viral abundance had decreased by 72% (standard deviation, 6%; n = 6). Aldehyde fixation of samples followed by storage at 4°C, for even a few hours, resulted in large underestimates of viral abundance. The viral loss rates were not constant, and in glutaraldehyde- and formaldehyde-fixed samples they decreased from 0.13 and 0.17 h−1 during the first hour to 0.01 h−1 between 24 and 48 h. Although decay rates changed over time, the abundance was predicted by using separate models to describe decay over the first 8 h and decay beyond 8 h. Accurate estimates of abundance were easily made with unfixed samples stained with Yo-Pro-1, SYBR Green I, or SYBR Gold, and slides could be stored at −20°C for at least 2 weeks or, for Yo-Pro-1, at least 1 year. If essential, samples can be fixed and flash frozen in liquid nitrogen upon collection and stored at −86°C. Determinations performed with fixed samples result in large underestimates of abundance unless slides are made immediately or samples are flash frozen. If protocols outlined in this paper are followed, EFM yields accurate estimates of viral abundance.


2003 ◽  
Vol 91 (11) ◽  
Author(s):  
Pierre Crançon ◽  
J. van der Lee

AbstractUranium is known to easily form stable complexes with both organic and inorganic ligands in natural aquatic environments. The potential mobility of U(VI), and particularly the role of humic substances, has been investigated for a sandy podzol. Adsorption of U(VI) at equilibrium was experimentally investigated, comparatively for a pure quartz sand as well as a sandy podzolic soil from Landes Gascony, France, containing 0.6 wt. organic matter. Uranium is strongly retained by the bulk soil, mainly due to organic aggregates (<50μm) and organic coatings on quartz grains. A large fraction of U(VI) is found to be associated to humic colloids in soil, thus forming a potential mobile uranium phase. For the soil, the U(VI) adsorption isotherm is linear for relatively low U(VI) total aqueous concentration, ranging from 15 to 40000μg/L. This indicates that the functional groups of humic matter are far from saturated for aqueous concentrations close to U(VI) solubility in soil pore-water. The speciation of uranium in soil pore water and the interactions between U(VI) species and the reactive sites of the soil material were evaluated using the speciation code CHESS [1]. Comparison between the model and experimental results show that complexation of U(VI) by humic substances tends to immobilise uranium in soils with a pH below 5, when the reactive surface of quartz grains and aggregates are entirely coated by humic matter. In soil pore-water, the presence of mobile organic ligands competing with surface-bound organics for U(VI) complexation must be included in the speciation modelling. Without the mobile organic phase, the model overestimates the actual bound fraction, thus underestimating the actual amount of mobile U(VI).


Author(s):  
Ayaz Muhammad Khan ◽  
Amber Jamshaid ◽  
Tayyibah Roohi ◽  
Amna Ramzan

Sustainable Development (SD) is a rich, challenging and thought-provoking construct in social sciences. The main purpose of this paper was to identify and explore the role played by primary school teachers in building up the idea of sustainable development (SD) among students. This paper was intended to identify that how a teacher can successfully execute the concept of SD by influencing students’ minds at the primary level. Quantitative survey technique were utilized for data collection. All the primary school teachers of Lahore division comprised the population of the study. Through multistage sampling technique, 352 primary school teachers were selected as participants of the study. A self-developed SD questionnaire incorporating four major factors (teachers’ awareness, pedagogy, curricular and co-curricular activities) with Cronbach’s alpha value = .93 was used to measure the role of teachers in building the sustainability concept among students at primary level. The results indicated a significant mean score difference among SD scores of teachers, sector wise (private and public). Furthermore, the results also reconnoitered the significant difference (p=.04) between the mean scores of female and male teachers in building up the SD concept in students’ minds.


2020 ◽  
Vol 5 (2) ◽  
pp. 49-55
Author(s):  
Hafiko Andresni ◽  
Zahtamal Zahtamal ◽  
Winda Septiani ◽  
Mitra Mitra ◽  
Lita Lita

ABSTRACT Toilet training is an effort to train children to be able to control and urinate (BAK) and defecate (BAB). Toilet training is one of the main tasks of children at toddler age. Toilet training is one of the main tasks of children in toddler age which is very important to be done to create independence in children in controlling BAK and BAB and children know the parts of the body and their functions. Data in 2012 shows that ± 60% of parents do not teach toilet training to children from an early age. The aim of the study was to find out the effectiveness of toilet training education on maternal behavior and toilet skills in toddler age training (18-36 months). The study was conducted in July-August 2018. This type of quantitative research used the design of the Quasy pretest and posttest experiment with non-equivalent control group design. Samples were 36 mothers and 36 children with purposive sampling technique. Data analysis used Paired t test, Wilcoxon test, Man-Whitney test an Independent t test. The results showed that toilet training education through lecture methods, modules and maze games was more effective than toilet training education through lecture and leaflet methods on children's knowledge and abilities. Conversely, for the role of mothers in supervision there is no significant difference in effectiveness. Health education is recommended in health promotion programs to increase maternal knowledge, the role of mothers and the ability of toilet training children independently. Keywords: Toilet training, Lecture method, Module, Maze game, Leaflet, Knowledge, Role of mother, Children's ability.


Author(s):  
Sanjeeva Kumar Goud T ◽  
Rahul Kunkulol

The present study was aimed to study the effect of Sublingual Vitamin D3 on Serum Vitamin D level in Vitamin D deficiency patients. This was a cross-sectional and interventional study. All the Vitamin D deficiency patients of age 18-60years and either gender, willing to participate in the study were included. Patients who had greater than 20 ng/ml were excluded from the study. The total number of participants in our study was 200, out of these 111 males and 89 females, the mean age in our study was 51.07 ± 7.39Yrs. All volunteers were given sublingual vitamin D3 (60,000IU) in six doses every fifteen days of follow up for 3 months. The subject’s serum 25(OH)D levels were estimated before and after the treatment of sublingual vitamin D3. There was a statistically significant difference in serum vitamin D3 level before 16.61±6.71 ng/ml and after 35.80±7.80 ng/ml after treatment with Sublingual Vitamin D3. Six doses of 60,000IU of Vitamin D3 sublingual route having improved the role of serum 25(OH)D levels in the treatment of Vitamin D3 deficiency patients.Keywords: Vitamin D3; Sublingual route


2008 ◽  
Vol 47 (01) ◽  
pp. 18-23 ◽  
Author(s):  
M. Wehrschuetz ◽  
B. Bisail ◽  
M. Woltsche ◽  
T. Schwarz ◽  
H. Lanz ◽  
...  

SummaryAim: 67Ga citrate has been used long and successfully to diagnose and stage sarcoidosis. 18F-fluorodeoxyglucose (18F-FDG) has been suggested as a positron emission tomography (PET) tracer for sarcoidosis imaging. This study aimed to analyze possible advantages of 18F-FDG-PET over 67Ga citrate scintigraphy during the primary assessment of patients with sarcoidosis. Patients and methods: Twentyfour patients (11 men, 13 women, aged 52 years ±12.4) with histologically proven sarcoidosis were investigated with 18F-FDG and 67Ga citrate. Equipment included a fullring PET scanner (ECAT EXACT HR+, Siemens/CTI, Knoxville TN, USA) and a double-headed gamma camera (ECAM, Siemens, Illinois, USA) for scintigraphy. The mean time difference between the two studies was 6.5 days (range: 5–8 days). Results: There was a significant difference in the detection of pulmonary and nonpulmonary sarcoidosis lesions between planar 67Ga citrate scans and 18F-FDG-PET images (<0.0021). A total of 64 lesions were detected with 67Ga citrate scans in the thorax and elsewhere with a mean of 2.6 lesions (4%) per patient, while 85 lesions were found with 18F-FDG-PET, with a mean of 3.5 lesions (4.1%) per patient. There was complete agreement between 18F-FDG and 67Ga citrate in thoracic manifestations in four (16.6%) patients, and in non-thoracic manifestations in five (20.8%) patients. The interobserver variability showed a kappa value of 0.79. Conclusion: 67Ga citrate and 18F-FDG are useful tracers for diagnostic evaluation of thoracic sarcoidosis. 18F-FDG seems to be more suitable for imaging the mediastinum, the bi-hilar lymph nodes, the posterior regions of the lungs and non-thoracic lesions. Further prospective studies are needed to clarify the role of both tracers in early diagnosis and staging of sarcoidosis, and to resolve questions concerning medical treatment and follow-up.


MicroRNA ◽  
2020 ◽  
Vol 09 ◽  
Author(s):  
Sadniman Rahman ◽  
Chaity Modak ◽  
Mousumi Akter ◽  
Mohammad Shamimul Alam

Background: Learning and memory is basic aspects in neurogenetics as most of the neurological disorders start with dementia or memory loss. Several genes associated with memory formation have been discovered. MicroRNA genes miR-1000 and miR-375 were reported to be associated with neural integration and glucose homeostasis in some insects and vertebrates. However, neuronal function of these genes is yet to be established in D. melanogaster. Objective: Possible role of miR-1000 and miR-375 in learning and memory formation in this fly has been explored in the present study. Methods: Both appetitive and aversive olfactory conditional learning were tested in the miR-1000 and miR-375 knockout (KO) strains and compared with wild one. Five days old third instar larvae were trained by allowing them to be associated with an odor with reward (fructose) or punishment (salt). Then, the larvae were tested to calculate their preferences to the odor trained with. Learning index (LI) values and larval locomotion speed were calculated for all strains. Results: No significant difference was observed for larval locomotion speed in mutant strains. Knockout strain of miR-1000 showed significant deficiency in both appetitive and aversive memory formation whereas miR-375 KO strain showed a significantly lower response only in appetitive one. Conclusion: The results of the present study indicate important role played by these two genes in forming short-term memory in D. melanogaster.


2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Selene Rubiola ◽  
Tiziana Civera ◽  
Felice Panebianco ◽  
Davide Vercellino ◽  
Francesco Chiesa

Abstract Background Cattle are intermediate hosts of six Sarcocystis species, among which Sarcocystis hominis and Sarcocystis heydorni can infect humans through the consumption of raw or undercooked meat. In addition to the zoonotic potential, there is increasing interest in these protozoa because of the evidence supporting the role of Sarcocystis spp. in the occurrence of bovine eosinophilic myositis (BEM), a specific inflammatory myopathy which leads to carcass condemnation and considerable economic losses. Actually, all the prevalence studies carried out on cattle in Italy have been based on either morphological or 18S rDNA-based molecular techniques, most likely leading to misidentification of closely related species. Therefore, there is a strong need for new data on the prevalence of the different Sarcocystis spp. in cattle in Italy and their association with bovine eosinophilic myositis. Methods To reach our aim, individual striated muscle samples from BEM condemned carcasses (N = 54) and diaphragm muscle samples from randomly sampled carcasses (N = 59) were obtained from Northwest Italy slaughterhouses. Genomic DNA was extracted and analyzed by multiplex-PCR targeting 18S rDNA and cox1 genes. PCR products amplified using the genus-specific primer set in absence of the specific fragment for S. hirsuta, S. cruzi, S. hominis or S. bovifelis were sequenced to achieve species identification. Results Sarcocystis DNA was detected in 67.8% of the samples from slaughter cattle and in 90.7% of the samples from BEM condemned carcasses. S. cruzi was identified as the most prevalent species in slaughter cattle (61%), followed by S. bovifelis (10.2%), S. hominis (8.5%) and S. hirsuta (1.7%). Notably, among the different Sarcocystis spp. detected, the presence of S. bovifelis and S. hominis was significantly higher in samples isolated from BEM condemned carcasses (46.3% and 40.7% respectively), while there was no statistically significant difference between the presence of S. cruzi or S. hirsuta in BEM condemned carcasses (42.6% and 1.8%, respectively) and randomly sampled carcasses. Furthermore, DNA sequence analysis revealed the presence of a putative new species in two carcasses. Conclusions Our study contributes to updating the data on the prevalence of the different Sarcocystis spp. in cattle in Italy, highlighting the presence of three Sarcocystis spp., S. cruzi, S. hominis and S. bovifelis, in BEM lesions and allowing us to speculate on the possible role of S. hominis and S. bovifelis as the major sarcosporidian species involved in bovine eosinophilic myositis. Graphic Abstract


2021 ◽  
pp. 037957212110254
Author(s):  
Harleen Kaur ◽  
Neerja Singla ◽  
Rohini Jain

Objective: India is the second country after China having the highest population prevalence of diabetes. Several research studies investigating diabetes have been done, but not much work has been done on prediabetes. The purpose of this study was to investigate the effect of nutrition and lifestyle modification on prediabetic females. Methods: A total of 120 prediabetic females from Ludhiana city were divided into 2 matched groups: control group (n = 60) and experimental group (n = 60). Impact of nutrition intervention for dietary and lifestyle modification (for 3 months) was assessed on the anthropometric, dietary, biochemical parameters, and diabetes risk score of the experimental group and control group (no intervention). Results: All the selected 120 subjects completed the study (experimental group = 60; control group = 60). There was significant difference in the changes between the 2 groups throughout the study. The fasting blood glucose and glycated hemoglobin A1c levels of the experimental group subjects reduced significantly ( P ≤ .01). However, no change was observed among the control group subjects. The lipid profile of the experimental group showed a significant improvement ( P ≤ .01). Conclusion: Nutrition counselling of the prediabetics regarding dietary and lifestyle modification is recommended so as to improve their metabolic control, thus preventing them from being diabetics.


Genetics ◽  
1978 ◽  
Vol 89 (2) ◽  
pp. 355-370 ◽  
Author(s):  
Allen Shearn ◽  
Grafton Hersperger ◽  
Evelyn Hersperger ◽  
Ellen Steward Pentz ◽  
Paul Denker

ABSTRACT The phenotypes of five different lethal mutants of Drosophila melanogaster that have small imaginal discs were analyzed in detail. From these results, we inferred whether or not the observed imaginal disc phenotype resulted exclusively from a primary imaginal disc defect in each mutant. To examine the validity of these inferences, we employed a multiple-allele method. Lethal alleles of the five third-chromosome mutations were identified by screening EMS-treated chromosomes for those which fail to complement with a chromosome containing all five reference mutations. Twenty-four mutants were isolated from 13,197 treated chromosomes. Each of the 24 was then tested for complementation with each of the five reference mutants. There was no significant difference in the mutation frequencies at these five loci. The stage of lethality and the imaginal disc morphology of each mutant allele were compared to those of its reference allele in order to examine the range of defects to be found among lethal alleles of each locus. In addition, hybrids of the alleles were examined for intracistronic complementation. For two of the five loci, we detected no significant phenotypic variation among lethal alleles. We infer that each of the mutant alleles at these two loci cause expression of the null activity phenotype. However, for the three other loci, we did detect significant phenotypic variation among lethal alleles. In fact, one of the mutant alleles at each of these three loci causes no detectable imaginal disc defect. This demonstrates that attempting to assess the developmental role of a gene by studying a single mutant allele may lead to erroneous conclusions. As a byproduct of the mutagenesis procedure, we have isolated two dominant, cold-sensitive mutants.


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