scholarly journals Starvation resistance of invasive lace bug Corythucha ciliata (Hemiptera: Tingidae) in China

2016 ◽  
Vol 27 (1) ◽  
pp. 8-14 ◽  
Author(s):  
Hai-Wei Wu ◽  
Xian-Chen Li ◽  
Huan-Xiu Liu

Food shortage is a prevalent threat to insect survival and successful reproduction in natural settings. An insect species invading new areasmay have a high capacity to survive and adapt to starvation. To test these hypotheses, we assessed the survival time of Corythucha ciliata (Say), in a laboratory under two starvation conditions: complete starvation (no food supplied) and gradual starvation (food provided once and not replenished). Under complete starvation, survival of 3rd to 5th instar nymphs tended to decline steadily, whereas under gradual starvation this process was delayed in the initial stage. The average survival times increased as the instar increased under both conditions (14.0 h, 15.9 h and 24.4 h under complete starvation conditions; 27.8 h, 29.6 h and 33.6 h under gradual starvation conditions). The longest lived individual nymph survived for 49 hours. The results may partially explain the rapid global expansion of C. ciliata.

2022 ◽  
Vol 12 ◽  
Author(s):  
Nian Liu ◽  
Zekai Lu ◽  
Ying Xie

Background and AimsThere are no accurate statistical data on the relapse rate of drug abstainers after compulsory detoxification in China. This study aimed to collect relapse data for drug abstainers through follow-up visits, verify the effectiveness of professional social worker services and explore significant factors affecting relapse.Design and SettingThe drug abstainers released from Guangzhou T Compulsory Isolated Detoxification Center were randomly divided into two groups. The difference between the experimental group and the control group is that assistance services were provided by social workers to the former.ParticipantsThe study included 510 drug abstainers released from T Center, including 153 in the experimental group and 357 in the control group.MeasurementsDemographic information, history of drug abuse, and motivation for drug rehabilitation (SOCRATES) were collected 1 month prior to drug abstainer release from compulsory detoxification. Then, the relapse situation after their release was tracked according to fixed time points.FindingsThe overall relapse rate of 510 drug abstainers after their release from compulsory detoxification was 47.6%. The average survival time to relapse based on survival analysis was 220 days (N = 486), as calculated with Bayesian estimation by the MCMC method. The average survival times to relapse of the experimental group and control group were 393 and 175 days, respectively. By taking the specific survival time as the dependent variable and the group as the control variable (OR = 25.362), logistic regression analysis showed that marital status (OR = 2.666), previous compulsory detoxification experience (OR = 2.329) and location of household registration (OR = 1.557) had a significant impact on the survival time to relapse.ConclusionsThe occurrence of relapse among drug patients released from compulsory detoxification can be delayed effectively through the intervention of professional social worker services. Regardless of whether patients receive aftercare after compulsory detoxification, drug-using patients who are single, have multiple detoxification experiences and whose households are registered in other provinces deserve special attention. Relevant suggestions to avoid relapse are provided.


2020 ◽  
Vol 113 (5) ◽  
pp. 2540-2545
Author(s):  
G Resquín-Romero ◽  
C Cabral-Antúnez ◽  
H Sarubbi-Orue ◽  
I Garrido-Jurado ◽  
P Valverde-García ◽  
...  

Abstract Three strains of fungi belonging to the genus Metarhizium Sorokīn (ARSEF 4556, ARSEF 3297, native strain) were assayed against adults and nymphs of the Neotropical brown stinkbug Euschistus heros (F.) and the green-belly stinkbug Dichelops furcatus (F.). The most virulent strain, ARSEF 4556, caused over 90% mortality. The average survival time of the second and fifth instar nymphs and adults following immersion in 1 × 108 conidia ml−1 was 4.8, 5.7, and 5.2 d, respectively. The second instar nymphs were more susceptible than the adults. The LC50 values and median survival times for second instar and adult E. heros were 1.6 × 107 and 3.1 × 107 conidia ml−1 and 6 and 8 d, respectively. Eggs of E. heros and the closely related stinkbug, D. furcatus, were highly susceptible to ARSEF 4556 with the mean mortality of eggs immersed in 1 × 108 conidia ml−1 being 77.4% and 89.7%, respectively. The strain 3297 showed also good aptitudes for stinkbugs control with mortalities higher than 80% against nymphs and adults and eggs mortalities of 75.5% for E. heros and 79.6% for D. furcatus. This study has shown that it is possible to have a two-pronged control strategy, targeting adults and to reduce oviposition and targeting egg clusters to prevent emergence and dispersal of nymphs. Besides early instars of nymphs have been shown to be more susceptible to the fungal strains than late instars and adults.


2020 ◽  
Vol 7 (2) ◽  
pp. 107-112
Author(s):  
Marian Manciu ◽  
Sorour Hosseini ◽  
Joscelyne Guzman-Gonzalez

Background: Statistical methods commonly used in survival analysis typically provide the probability that the difference between groups is due to chance, but do not offer a reliable estimate of the average survival time difference between groups (the difference between median survival time is usually reported). Objective: We suggest a Maximum-Entropy estimator for the average Survival Time Difference (MESTD) between groups. Methods: The estimator is based on the extra survival time, which should be added to each member of the group, to produce the maximum entropy of the result (resulting in the groups becoming most similar). The estimator is calculated only from time to event data, does not necessarily assume hazard proportionality and provides the magnitude of the clinical differences between the groups. Results: Monte Carlo simulations show that, even at low sample numbers (much lower than the ones needed to prove that the two groups are statistically different), the MESTD estimator is a reliable predictor of the clinical differences between the groups, and therefore can be used to estimate from (low sample numbers) preliminary data whether or not the large sample number experiment is worth pursuing. Conclusion: By providing a reasonable estimate for the efficacy of a treatment (e.g., for cancer) even for low sample data, it might provide useful insight in testing new methods for treatment (for example, for quick testing of multiple combinations of cancer drugs).


2019 ◽  
Vol 3 (s1) ◽  
pp. 37-37
Author(s):  
Jo Ellen Wilson ◽  
Sarasota Mihalko ◽  
Stephan Heckers ◽  
Pratik P. Pandharipande ◽  
Timothy D. Girard ◽  
...  

OBJECTIVES/SPECIFIC AIMS: Delirium, a form of acute brain dysfunction, characterized by changes in attention and alertness, is a known independent predictor of mortality in the Intensive Care Unit (ICU). We sought to understand whether catatonia, a more recently recognized form of acute brain dysfunction, is associated with increased 30-day mortality in critically ill older adults. METHODS/STUDY POPULATION: We prospectively enrolled critically ill patients at a single institution who were on a ventilator or in shock and evaluated them daily for delirium using the Confusion Assessment for the ICU and for catatonia using the Bush Francis Catatonia Rating Scale. Coma, was defined as a Richmond Agitation Scale score of −4 or −5. We used the Cox Proportional Hazards model predicting 30-day mortality after adjusting for delirium, coma and catatonia status. RESULTS/ANTICIPATED RESULTS: We enrolled 335 medical, surgical or trauma critically ill patients with 1103 matched delirium and catatonia assessments. Median age was 58 years (IQR: 48 - 67). Main indications for admission to the ICU included: airway disease or protection (32%; N=100) or sepsis and/or shock (25%; N=79. In the unadjusted analysis, regardless of the presence of catatonia, non-delirious individuals have the highest median survival times, while delirious patients have the lowest median survival time. Comparing the absence and presence of catatonia, the presence of catatonia worsens survival (Figure 1). In a time-dependent Cox model, comparing non-delirious individuals, holding catatonia status constant, delirious individuals have 1.72 times the hazards of death (IQR: 1.321, 2.231) while those with coma have 5.48 times the hazards of death (IQR: 4.298, 6.984). For DSM-5 catatonia scores, a 1-unit increase in the score is associated with 1.18 times the hazards of in-hospital mortality. Comparing two individuals with the same delirium status, an individual with a DSM-5 catatonia score of 0 (no catatonia) will have 1.178 times the hazard of death (IQR: 1.086, 1.278), while an individual with a score of 3 catatonia items (catatonia) present will have 1.63 times the hazard of death. DISCUSSION/SIGNIFICANCE OF IMPACT: Non-delirious individuals have the highest median survival times, while those who are comatose have the lowest median survival times after a critical illness, holding catatonia status constant. Comparing the absence and presence of catatonia, the presence of catatonia seems to worsen survival. Those individual who are both comatose and catatonic have the lowest median survival time.


2009 ◽  
Vol 77 (9) ◽  
pp. 3948-3957 ◽  
Author(s):  
Birgit Rathkolb ◽  
Harry A. Noyes ◽  
Andy Brass ◽  
Paul Dark ◽  
Helmut Fuchs ◽  
...  

ABSTRACT Trypanosoma congolense is a protozoan parasite that causes severe diseases in livestock. Three major quantative trait loci (QTL), Tir1, Tir2, and Tir3, control the survival time of mice after infection with T. congolense. Congenic mice carrying the C57BL/6 resistance alleles on the A/J background were developed for each of these loci. The congenic mice were used to physically map the regions containing the QTL gene(s) and to investigate the physiological effect of each locus. Clinical chemistry data for infected A/J, C57BL/6, and BALB/c mice were obtained for 15 analytes at five time points. Congenic mice were assessed for survival, parasitemia, and anemia as well as seven clinical-chemical analytes. The survival times were significantly increased in the Tir1 and Tir2 mice but not Tir3 congenic mice. The survival time of the parental inbred mice correlated negatively with parasitemia but positively with alanine aminotransferase activities in serum, suggesting that inflammatory reactions in the liver had a beneficial effect possibly associated with reduced parasitemia. However, there was no difference in parasitemia or liver enzyme activities of Tir1 and Tir2 congenic mice relative to their controls, showing that survival, parasitemia, and degree of liver damage are not associated with each other, despite the correlation in the parental lines. These data suggest that the congenic loci affect survival but do not affect control of parasite number. They may therefore act by limiting the pathological consequences of T. congolense infection.


Author(s):  
A. W. H. Bé ◽  
D. A. Caron ◽  
O. R. Anderson

Globigerinoides sacculifer (Brady), a common planktonic foraminifer collected by SCUBA off Barbados, was maintained under six feeding regimes at constant light and temperature conditions. Five groups of 63 specimens each were fed 1-day-old Anemia at the rate of one nauplius per specimen every 1, 2, 3, 4 or 7 days. A starved control group received no Anemia. The rate of chamber formation and shell size increased proportional to the feeding frequency. However, an inverse correlation existed between survival time and feeding frequency. Normally, survival time ends with gametogenesis which terminates the life of the mother cell. Organisms fed more frequently reached maturity and underwent gametogenesis more rapidly than those fed less frequently. The average survival time of G. sacculifer in culture ranged from 7 days for the daily-fed group to 11 days for the group fed every 7 days. While the latter grew more slowly they eventually reached maturity. Starved individuals rarely formed chambers and often died without undergoing gametogenesis. Symbiotic zooxanthellae presumably prolonged survival of starved organisms. Extrapolation of survival data suggests G. sacculifer has a variable life span of 2 to 4 weeks depending on food availability.


1981 ◽  
Vol 54 (4) ◽  
pp. 461-467 ◽  
Author(s):  
Alexander M. Spence ◽  
Joseph P. Geraci

✓ The combination of cyclotron fast-neutron radiotherapy with BCNU chemotherapy was compared to 137Cs gamma photon radiotherapy combined with BCNU in the 36B-10, F-344 rat-transplanted glioma model. Radiation and drug treatments were administered 7 to 8 days after intracerebral tumor implantation. Increase in animal survival time was used as the measure of the effectiveness of various treatment schedules. Single-dose neutron or gamma radiotherapy was tested on Day 7 over the ranges 0 to 900 rads and 0 to 2000 rads, respectively. This therapy produced increases in mean survival times up to 70% at the highest radiation doses. When BCNU (10 mg/kg body weight) was administered intravenously on Day 8, 1 day following radiotherapy, mean survival times were increased by an additional 35% to 50%, irrespective of the dose or type of irradiation. In contrast, by using the same radiation and drug doses but scheduling combined therapy trials so that BCNU was administered 1 hour before either neutron or gamma irradiation on Day 7, there was enhancement of the radiation effect by BCNU. Under these conditions, the maximum enhancement of the mean survival time was 70% to 75% in neutron-treated animals and 120% to 150% in gamma-treated animals. Treatment with BCNU 1 hour before or 1 day after neutron irradiation proved to be no more effective in improving the survival time of tumor-bearing animals than the drug similarly combined with conventional gamma irradiation.


2000 ◽  
Vol 18 (9) ◽  
pp. 1928-1935 ◽  
Author(s):  
Robert J. Motzer ◽  
Madhu Mazumdar ◽  
Jennifer Bacik ◽  
Paul Russo ◽  
William J. Berg ◽  
...  

PURPOSE: To evaluate the relationship between treatment with cytokine therapy and survival, investigate the effect of nephrectomy on survival, and identify long-term survivors among a cohort of 670 patients with advanced renal cell carcinoma (RCC). PATIENTS AND METHODS: A total of 670 patients with advanced RCC treated on 24 clinical trials of systemic chemotherapy or cytokine therapy were the subjects of this retrospective analysis. Treatment was categorized as cytokine (containing interferon alfa and/or interleukin-2) in 396 patients (59%) and as chemotherapy (cytotoxic or hormonal therapy) in 274 (41%). Among the 670 patients, those with survival times of greater than 5 years were identified as long-term survivors. RESULTS: Patients treated with cytokine therapy had a longer survival time than did those treated with chemotherapy, regardless of the year of treatment or risk category based on pretreatment features. The median survival times for favorable-, intermediate-, and poor-risk patients were 27, 12, and 6 months for those treated with cytokines and 15, 7, and 3 months for those treated with chemotherapy, respectively. The magnitude of difference in median survival was greater in the favorable- and intermediate-risk groups. The median survival time was less than 6 months in the poor-risk group for both treatment programs. Median survival time was 14 months among patients with prior nephrectomy plus time from diagnosis to treatment greater than 1 year versus 8 months among those with time from diagnosis to treatment less than 1 year, regardless of pretreatment nephrectomy status. Thirty patients (4.5%) among the 670 patients were identified as long-term survivors; 12 were free of disease after nephrectomy and treatment with interferon alfa, interleukin-2, or surgical resection of metastasis. CONCLUSION: The low proportion of patients with advanced RCC who achieve long-term survival emphasizes the need for clinical investigation to identify more effective therapy.


1997 ◽  
Vol 22 (1) ◽  
pp. 420-421 ◽  
Author(s):  
John D. Vandenberg ◽  
Mark Ramos

Abstract Fifty-five isolates of four fungi, Beauveria bassiana (Balsamo) Vuillemin, Fursarium sp.,Metarhizium anisopliae (Metschnikoff) Sorokin and Paecilomyces farinosus (Holm ex SF Gray) Brown & Smith, were obtained from the USDA-ARS Collection of Entomopathogenic Fungal Cultures (Ithaca, NY). Isolates were subcultured once after retrieval from liquid nitrogen storage. Cultures were maintained on Subouraud dextrose agar plus 2% yeast extract (SDAY) at 24° Cunder a photoperiod of 15:9 h (L:D) for 14 to 21 d. Conidia were scraped from the culture surface and suspended in 0.01 % Tween 80 by vortexting for 2 min. Suspensions were filtered through 16 layers of sterile cheesecloth to remove conidial clumps and hyphal fragments. Spore concentrations were estimated using a hemacytometer and then adjusted to 312,500 spores/ml. Three to 7 isolates were screened against isolate ARSEF 4543 as a standard derived from a single infected DBM larva collected in Ontario County, NY, in 1994. First instars of DBM maintained on wheat germ diet. Fifteen 2nd instars were placed 2–3 h prior to inoculation in a petri dish containing filter paper moistened with deionized water and incubated at 4° C. Dishes were assigned randomly to treatments with 4 replicates each for each isolate. Insects were inoculated at room temperature (–22° C) using a Bergergon spray tower equipped with a Spraying Systems 2850 noz-zle, calibrated to deliver 312.5 spores/cm2 using 5 ml suspension at a concentration of 312,500 spores/ml. DBM larvae treated only with the suspending medium (0.01% Tween 80) served as checks. (Mortality in the checks was minimal and no evidence of fungal infection was detected.) After spraying the insects, two discs of DBM larval diet (Bioserv Premix) were placed in each dish which was then sealed with parafilm and incubated at 25° C in darkness for 24 h. Thereafter, the insects were transferred to a sterile petri dish with fresh diet and incubated at 25° C under a photoperiod of 15:9 h (L:D). Larvae were monitored daily and diet was replaced as needed for 7 d. Dead larvae were transferred to petri dishes containing a piece of moistened filter paper. Mycosis was confirmed by observing characteristic mycelial eruption from cadavers and subsequent sporulation. To confirm viability of spore suspensions and dosage, 5 ml of each was sprayed on SDAY plates which were incubated at 25° Cunder a photoperiod of 15:9 h (L:D) for 3 d until identifiable fungal colonies were counted. To estimate the potency of each isolate relative to the standard (ARSEF 4543), the percentage mortality due to fungus infection was divided by the percentage mortality due to infection by the standard within that experiment. Average survival times were also estimated for all fungus-killed larvae for each isolate from records of the number of days from inoculation to death.


1956 ◽  
Vol 186 (3) ◽  
pp. 554-556
Author(s):  
Donn L. Smith ◽  
Irvin I. Kibbey ◽  
Max E. Bierwagen ◽  
J. R. Cruse

Intravenous administration of colloidal saccharated iron oxide prior to intestinal traumatization in the albino rat resulted in a significant reduction of the mean survival time. Sodium gold thiosulfate and colloidal manganese hydroxide employed in the same manner did not significantly alter mean survival times. ACTH and cortisone did not modify the deleterious effects of iron in experimental traumatic shock. A decrease in soluble liver iron was observed when traumatization followed the injection of iron. It was concluded that the reduction of mean survival time in iron injected, traumatized animals was due to a specific action of iron and is not the result of generalized heavy metal toxicity.


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