Bionomics of the entomopathogenic nematode, Steinernema weiseri (Rhabditida: Steinernematidae)

Nematology ◽  
2008 ◽  
Vol 10 (5) ◽  
pp. 735-742 ◽  
Author(s):  
Ipek Bazman ◽  
Nurdan Ozer ◽  
Selcuk Hazir
Keyword(s):  
Galleria Mellonella ◽  
Entomopathogenic Nematode ◽  
Nematode Species ◽  
Head Capsule ◽  
Cold Temperatures ◽  
Larval Stages ◽  
Group 4 ◽  
Group 2 ◽  
New Generation ◽  
Steinernema Weiseri

Abstract This study describes some important bio-ecological properties of Steinernema weiseri, a recently isolated entomopathogenic nematode species in Turkey. The effects of temperature on the infectivity and development of S. weiseri were determined at 5, 8, 10, 15, 20, 25 and 30°C. The greatest and the fastest mortality of Galleria mellonella larvae was observed at 20 and 25°C (ca 2 days) and the slowest at 5°C in 11.5 days. The emergence time of the new generation of infective juveniles (IJ) from the host cadaver was shortest at 20 and 25°C (ca 9 days) and the longest at 8°C (ca 40 days). No progeny were observed at 5 and 30°C. At the tested temperatures, the lowest number of new generation IJ was obtained at 8 and 10°C and the highest at 15 and 20°C. The life cycle, determined at 23-24°C under laboratory conditions using G. mellonella as a host, took 9 days to complete. Our study suggests that the Turkish isolate of S. weiseri is adapted to cold temperatures. Steinernema weiseri has a wide host range and infects and develops well in larvae of Agrotis sp., Ceratitis capitata, Cydia splendana, Synanthedon vespiformis and Hoplocampa flava, but it infects and develops poorly in Polyphylla fullo. Larval stages of C. cossus were divided into four groups based on the diameter of their head capsules. Steinernema weiseri developed well in larval stages in Group 1 (the smallest head capsule) and Group 2 of Cossus cossus but, interestingly, very low infection and nematode development occurred in the Group 3 and Group 4 larval stage of C. cossus. No nematode infection was observed in Gryllotalpa gryllotalpa either.

scholarly journals Transcriptional variation and divergence of host-finding behaviour in Steinernema carpocapsae infective juveniles

BMC Genomics ◽  
2019 ◽  
Vol 20 (1) ◽  
Author(s):  
Neil D. Warnock ◽  
Deborah Cox ◽  
Ciaran McCoy ◽  
Robert Morris ◽  
Johnathan J. Dalzell
Keyword(s):  
Galleria Mellonella ◽  
Entomopathogenic Nematode ◽  
Gene Families ◽  
Nematode Species ◽  
Host Finding ◽  
Steinernema Carpocapsae ◽  
Differentially Expressed ◽  
Infective Juvenile ◽  
Neuronal Genes ◽  
Sodium Transporter

Abstract Background Steinernema carpocapsae is an entomopathogenic nematode that employs nictation and jumping behaviours to find potential insect hosts. Here we aimed to investigate the transcriptional basis of variant host-finding behaviours in the infective juvenile (IJ) stage of three S. carpocapsae strains (ALL, Breton and UK1), with a focus on neuronal genes known to influence behaviour in other nematode species. Identifying gene expression changes that correlate with variant host-finding behaviours will further our understanding of nematode biology. Results RNA-seq analysis revealed that whilst up to 28% of the S. carpocapsae transcriptome was differentially expressed (P < 0.0001) between strains, remarkably few of the most highly differentially expressed genes (> 2 log2 fold change, P < 0.0001) were from neuronal gene families. S. carpocapsae Breton displays increased chemotaxis toward the laboratory host Galleria mellonella, relative to the other strains. This correlates with the up-regulation of four srsx chemosensory GPCR genes, and a sodium transporter gene, asic-2, relative to both ALL and UK1 strains. The UK1 strain exhibits a decreased nictation phenotype relative to ALL and Breton strains, which correlates with co-ordinate up-regulation of neuropeptide like protein 36 (nlp-36), and down-regulation of an srt family GPCR gene, and a distinct asic-2-like sodium channel paralogue. To further investigate the link between transcriptional regulation and behavioural variation, we sequenced microRNAs across IJs of each strain. We have identified 283 high confidence microRNA genes, yielding 321 predicted mature microRNAs in S. carpocapsae, and find that up to 36% of microRNAs are differentially expressed (P < 0.0001) between strains. Many of the most highly differentially expressed microRNAs (> 2 log2 fold, P < 0.0001) are predicted to regulate a variety of neuronal genes that may contribute to variant host-finding behaviours. We have also found evidence for differential gene isoform usage between strains, which alters predicted microRNA interactions, and could contribute to the diversification of behaviour. Conclusions These data provide insight to the transcriptional basis of behavioural variation in S. carpocapsae, supporting efforts to understand the molecular basis of complex behaviours in nematodes.

scholarly journals Efficacy of two entomopathogenic nematode species as potential biocontrol agents against the rosaceae longhorned beetle, Osphranteria coerulescens, under laboratory conditions

Nematology ◽  
2014 ◽  
Vol 16 (6) ◽  
pp. 729-737 ◽  
Author(s):  
Shervin Sharifi ◽  
Shervin Sharifi ◽  
Javad Karimi ◽  
Shervin Sharifi ◽  
Javad Karimi ◽  
...  
Keyword(s):  
Field Experiments ◽  
Galleria Mellonella ◽  
Entomopathogenic Nematode ◽  
Natural Habitat ◽  
Agar Plate ◽  
Nematode Species ◽  
Fruit Trees ◽  
Reproduction Rate ◽  
Longhorned Beetle ◽  
Laboratory Conditions

Rosaceae longhorned beetle, Osphranteria coerulescens, is an important pest of fruit trees that attacks all fruit trees belonging to the family Rosaceae in cold regions of Iran. The potential efficacy of two species of entomopathogenic nematodes (EPN), Heterorhabditis bacteriophora and Steinernema carpocapsae, against last instar larvae of this pest was tested under laboratory conditions. In plate assays, the larvae were susceptible to both EPN species but were more susceptible to S. carpocapsae (65.0-97.5% mortality) than H. bacteriophora (42.5-87.8%). Both nematode species were able to penetrate and reproduce within O. coerulescens larvae, but reproduction rate for H. bacteriophora was higher than those of S. carpocapsae; however, the penetration rate for S. carpocapsae was greater than H. bacteriophora. In a migration test on agar plate, S. carpocapsae showed negligible attraction to the pest or to Galleria mellonella cues. However, H. bacteriophora was strongly attracted to the sector of Petri dishes containing larvae. In a test using apricot tree branches, both species of EPN passed from mass frass of O. coerulescens larvae in the tip of the branches, penetrated into the larval galleries, and located and killed the larvae of O. coerulescens in their natural habitat deep inside the branches. Our findings provide the first insight into the biocontrol efficacy of EPN against O. coerulescens larvae, and highlight their potential for the control of this pest. Field experiments are needed to evaluate their potential under the environmental conditions in which rosaceae longhorned beetle larvae are found.

Attraction behaviour of three entomopathogenic nematode species towards infected and uninfected hosts

Parasitology ◽  
2006 ◽  
Vol 134 (5) ◽  
pp. 729-738 ◽  
Author(s):  
O. RAMOS-RODRÍGUEZ ◽  
J. F. CAMPBELL ◽  
J. M. CHRISTEN ◽  
D. I. SHAPIRO-ILAN ◽  
E. E. LEWIS ◽  
...  
Keyword(s):  
Galleria Mellonella ◽  
Entomopathogenic Nematode ◽  
Nematode Species ◽  
Infection Process ◽  
Foraging Strategies ◽  
Host Quality ◽  
Infection Status ◽  
Host Attraction ◽  
Host Infection ◽  
Volatile Cues

SUMMARYEntomopathogenic nematode infective juveniles are likely to encounter both uninfected and infected insects and host quality depends on the stage of the infection. We hypothesized that nematode response to infected hosts will change over the course of an infection. Here, we tested this hypothesis by focusing on the influence of host infection status on long-range attraction to host volatile cues. The attraction response of 3 nematode species (Steinernema carpocapsae, S. glaseri and S. riobrave) with different foraging strategies to infected and uninfected insects (Galleria mellonella and Tenebrio molitor) was tested at 24 h intervals from start of infection to emergence of infective juveniles from depleted host. As expected, based on their foraging strategies, S. carpocapsae was not very responsive to hosts, S. glaseri was highly responsive and S. riobrave was intermediate. Generally, the level of attraction did not change with time after infection and was similar between infected and uninfected hosts. An exception was S. glaseri infected T. molitor, which tended to be less attractive to S. glaseri than uninfected hosts. These results suggest that any influence of host infection status on infection behaviour is occurring at subsequent steps in the host-infection process than host attraction, or involves non-volatile cues.

Morphological Changes in the Rat Granulosa Cell Surface During Differentiation Induced by Estradiol and Gonadotropins

1977 ◽  
Vol 35 ◽  
pp. 484-485
Author(s):  
P. Bagavandoss ◽  
JoAnne S. Richards ◽  
A. Rees Midgley
Keyword(s):  
Cell Surface ◽  
Granulosa Cell ◽  
Morphological Changes ◽  
Follicular Development ◽  
Female Rats ◽  
Functional Changes ◽  
Group 4 ◽  
Group 3 ◽  
Group 5 ◽  
Group 2

During follicular development in the mammalian ovary, several functional changes occur in the granulosa cells in response to steroid hormones and gonadotropins (1,2). In particular, marked changes in the content of membrane-associated receptors for the gonadotropins have been observed (1).We report here scanning electron microscope observations of morphological changes that occur on the granulosa cell surface in response to the administration of estradiol, human follicle stimulating hormone (hFSH), and human chorionic gonadotropin (hCG).Immature female rats that were hypophysectcmized on day 24 of age were treated in the following manner. Group 1: control groups were injected once a day with 0.1 ml phosphate buffered saline (PBS) for 3 days; group 2: estradiol (1.5 mg/0.2 ml propylene glycol) once a day for 3 days; group 3: estradiol for 3 days followed by 2 days of hFSH (1 μg/0.1 ml) twice daily, group 4: same as in group 3; group 5: same as in group 3 with a final injection of hCG (5 IU/0.1 ml) on the fifth day.

Correlation of γ-radioactivity and Scanning Electron Microscopy in measurement of retention of 111Indium-labeled canine endothelial cells on synthetic vascular grafts

1989 ◽  
Vol 47 ◽  
pp. 886-887
Author(s):  
E.J. Prendiville ◽  
S. Laliberté Verdon ◽  
K. E. Gould ◽  
K. Ramberg ◽  
R. J. Connolly ◽  
...  
Keyword(s):  
Blood Flow ◽  
Ex Vivo ◽  
Vascular Grafts ◽  
Retention Data ◽  
Vascular Prostheses ◽  
Group 4 ◽  
Human Fibronectin ◽  
Insufficient Time ◽  
Group 3 ◽  
Group 2

Endothelial cell (EC) seeding is postulated as a mechanism of improving patency in small caliber vascular grafts. However the majority of seeded EC are lost within 24 hours of restoration of blood flow in previous canine studies . We postulate that the cells have insufficient time to fully develop their attachment to the graft surface prior to exposure to hemodynamic stress. We allowed EC to incubate on fibronectin-coated ePTFE grafts for four different time periods after seeding and measured EC retention after perfusion in a canine ex vivo shunt circuit.Autologous canine EC, were enzymatically harvested, grown to confluence, and labeled with 30 μCi 111 Indium-oxine/80 cm 2 flask. Four groups of 5 cm x 4 mm ID ePTFE vascular prostheses were coated with 1.5 μg/cm.2 human fibronectin, and seeded with 1.5 x 105 EC/ cm.2. After seeding grafts in Group 1 were incubated in complete growth medium for 90 minutes, Group 2 were incubated for 24 hours, Group 3 for 72 hours and Group 4 for 6 days. Grafts were then placed in the canine ex vivo circuit, constructed between femoral artery and vein, and subjected to blood flow of 75 ml per minute for 6 hours. Continuous counting of γ-activity was made possible by placing the seeded graft inside the γ-counter detection crystal for the duration of perfusion. EC retention data after 30 minutes, 2 hours and 6 hours of flow are shown in the table.

In-vivo evaluation of the effect of cyanoacrylate on prosthetic vascular graft infection – does cyanoacrylate increase the severity of infection?

VASA ◽  
2020 ◽  
Vol 49 (4) ◽  
pp. 281-284
Author(s):  
Atıf Yolgosteren ◽  
Gencehan Kumtepe ◽  
Melda Payaslioglu ◽  
Cuneyt Ozakin
Keyword(s):  
Vascular Graft ◽  
Graft Infection ◽  
Vascular Graft Infection ◽  
Group 4 ◽  
Significant Difference ◽  
Group 3 ◽  
Group 2 ◽  
Prosthetic Vascular Graft Infection ◽  
Group 1

Summary. Background: Prosthetic vascular graft infection (PVGI) is a complication with high mortality. Cyanoacrylate (CA) is an adhesive which has been used in a number of surgical procedures. In this in-vivo study, we aimed to evaluate the relationship between PVGI and CA. Materials and methods: Thirty-two rats were equally divided into four groups. Pouch was formed on back of rats until deep fascia. In group 1, vascular graft with polyethyleneterephthalate (PET) was placed into pouch. In group 2, MRSA strain with a density of 1 ml 0.5 MacFarland was injected into pouch. In group 3, 1 cm 2 vascular graft with PET piece was placed into pouch and MRSA strain with a density of 1 ml 0.5 MacFarland was injected. In group 4, 1 cm 2 vascular graft with PET piece impregnated with N-butyl cyanoacrylate-based adhesive was placed and MRSA strain with a density of 1 ml 0.5 MacFarland was injected. All rats were scarified in 96th hour, culture samples were taken where intervention was performed and were evaluated microbiologically. Bacteria reproducing in each group were numerically evaluated based on colony-forming unit (CFU/ml) and compared by taking their average. Results: MRSA reproduction of 0 CFU/ml in group 1, of 1410 CFU/ml in group 2, of 180 200 CFU/ml in group 3 and of 625 300 CFU/ml in group 4 was present. A statistically significant difference was present between group 1 and group 4 (p < 0.01), between group 2 and group 4 (p < 0.01), between group 3 and group 4 (p < 0.05). In terms of reproduction, no statistically significant difference was found in group 1, group 2, group 3 in themselves. Conclusions: We observed that the rate of infection increased in the cyanoacyrylate group where cyanoacrylate was used. We think that surgeon should be more careful in using CA in vascular surgery.

Defensive activity of Hesperidin against Ciprofloxacin induced hepatic injury in rabbits.

2019 ◽  
Vol 10 (03) ◽  
Author(s):  
Hawraa M. Murad ◽  
Tamadhur Hani Hussein ◽  
Audai Sulaiman Khudhair ◽  
Manal Muhi Murad ◽  
Jawad Kadhim Faris
Keyword(s):  
Body Weight ◽  
Bacterial Infections ◽  
Hepatoprotective Activity ◽  
The Body ◽  
Local Breed ◽  
Group 4 ◽  
Group 3 ◽  
Group 2 ◽  
Defensive Activity ◽  
Antioxidant Effects

This study was conducted to find out hepatoprotective activity of hesperidin (HES) 100mg/kg body weight (b.w.) against ciprofloxacin (CPX) 100 mg/kg induced hepatotoxicity in local breed rabbits .CPX is a broad spectrum antibiotic used for treatment of many bacterial infections. Twenty four male rabbits were divided into four groups ,group1: control, (1 ml/kg Saline orally) group 2: CPX (100 mg/kg orally) for (14) consecutive days , group 3: HES (100 mg//kg) orally for (14) consecutive days group 4: CPX (100 mg/kg orally) plus HES (100 mg//kg orally ) for (14) consecutive days. All the rabbits were killed on the (15) day of the experiment, and then the blood, and livers samples were taken. CPX induced hepatotoxicity was proved by a significant (p less than 0.01) reduction in the body weight ,and a significant (p less than 0.01) increased serum aspartate transaminase (AST), alanine transaminase (ALT) , Malonaldehyde enzyme (MAD) and histopathological changes. Protective hepatic toxicity effect and oxidative damage caused by CPX significantly (p less than 0.01) increasing in body weight and significantly (p less than 0.01) decreasing AST , ALT, MAD and improving tissue morphology in HES (100 mg//kg) . These results assure that HES (100 mg//kg) antioxidant effects can protect CPX-induced hepatotoxicity in rabbits.

Does Perioperative Hemoglobin A1c Level Affect the Incidence, Pattern and Mortality of Lower Extremity Amputation?

2019 ◽  
Vol 17 (4) ◽  
pp. 354-364
Author(s):  
Hassan Al-Thani ◽  
Moamena El-Matbouly ◽  
Maryam Al-Sulaiti ◽  
Noora Al-Thani ◽  
Mohammad Asim ◽  
...  
Keyword(s):  
Glycemic Control ◽  
Lower Extremity ◽  
Hazard Ratio ◽  
Lower Extremity Amputation ◽  
Group 4 ◽  
Group 3 ◽  
Group 5 ◽  
Group 2 ◽  
Extremity Amputation ◽  
Group 1

Background: We hypothesized that perioperative HbA1c influenced the pattern and outcomes of Lower Extremity Amputation (LEA). Methods: A retrospective analysis was conducted for all patients who underwent LEA between 2000 and 2013. Patients were categorized into 5 groups according to their perioperative HbA1c values [Group 1 (<6.5%), Group 2 (6.5-7.4%), Group 3 (7.5-8.4%), Group 4 (8.5-9.4%) and Group 5 (≥9.5%)]. We identified 848 patients with LEA; perioperative HbA1c levels were available in 547 cases (Group 1: 18.8%, Group 2: 17.7%, Group 3: 15.0%, Group 4: 13.5% and Group 5: 34.9%). Major amputation was performed in 35%, 32%, 22%, 10.8% and 13.6%, respectively. Results: The overall mortality was 36.5%; of that one quarter occurred during the index hospitalization. Mortality was higher in Group 1 (57.4%) compared with Groups 2-5 (46.9%, 38.3%, 36.1% and 31.2%, respectively, p=0.001). Cox regression analysis showed that poor glycemic control (Group 4 and 5) had lower risk of mortality post-LEA [hazard ratio 0.57 (95% CI 0.35-0.93) and hazard ratio 0.46 (95% CI 0.31-0.69)]; this mortality risk persisted even after adjustment for age and sex but was statistically insignificant. The rate of LEA was greater among poor glycemic control patients; however, the mortality was higher among patients with tight control. Conclusion: The effects of HbA1c on the immediate and long-term LEA outcomes and its therapeutic implications need further investigation.

scholarly journals Influence of Calving Ease on In-Line Milk Lactose and Other Milk Components

Animals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 842
Author(s):  
Ramūnas Antanaitis ◽  
Vida Juozaitienė ◽  
Dovilė Malašauskienė ◽  
Mindaugas Televičius ◽  
Mingaudas Urbutis ◽  
...  
Keyword(s):  
Milk Fat ◽  
Milk Protein ◽  
Average Percentage ◽  
Calving Ease ◽  
Group 4 ◽  
Lactose Concentration ◽  
Milk Components ◽  
Two Factors ◽  
Milk Urea ◽  
Group 2

The aim of our study was to determine how the ease of calving of cows may influence changes in lactose concentration and other milk components and whether these two factors correlate with each other. To achieve this, we compared data of calving ease scores and average percentage of in-line registered milk lactose and other milk components. A total of 4723 dairy cows from nine dairy farms were studied. The cows were from the second to the fourth lactation. All cows were classified according to the calving ease: group 1 (score 1)—no problems; group 2 (score 2)—slight problems; group 3 (score 3)—needed assistance; group 4 (score 4)—considerable force or extreme difficulty. Based on the data from the milking robots, during complete lactation we recorded milk indicators: milk yield MY (kg/day), milk fat (MF), milk protein (MP), lactose (ML), milk fat/lactose ratio (MF/ML), milk protein/lactose ratio (MP/ML), milk urea (MU), and milk electrical conductivity (EC) of all quarters of the udder. According to the results, we found that cows that had no calving difficulties, also had higher milk lactose concentration. ML > 4.7% was found in 58.8% of cows without calving problems. Cows with more severe calving problems had higher risk of mastitis (SCC and EC). Our data indicates that more productive cows have more calving problems compared to less productive ones.

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