Highest Number Of Survivors Research Articles

Development of inactivated heartwater (Ehrlichia ruminantium) vaccine in South Africa

Heartwater, Ehrlichia ruminantium infection in cattle, sheep, goats, and some wild ruminants, is an economically important disease in Africa characterized by high mortality rates in susceptible populations. In South Africa, the current commercial heartwater vaccine is an infection and treatment type of immunization using virulent live E. ruminantium organisms generated from blood of infected sheep with subsequent treatment of the animals with antibiotics at specific times during the course of infection. This vaccine has several inherent problems preventing its wide use as the vaccine must be administered intravenously and it does not protect against all the South African field isolates. A vaccine based on inactivation of Zimbabwean E. ruminantium Mbizi strain organisms produced in endothelial cell cultures can be a sustainable option because it will not require antibiotic treatment and will be safe as there is no potential for reversion to virulence. Previous data generated in laboratory trials and under natural field setting provides support for this vaccine approach.Four inactivated vaccine formulations using the E. ruminantium Mbizi strain were tested for their efficacy in Merino sheep compared to an unvaccinated control group (11 sheep per group). Two vaccines were prepared by beta-propiolactone (BPL) inactivation, and two were inactivated with binary ethylenimine (BEI) while purification was done with both percoll and polyethylene glycol (PEG). The four vaccine preparations were formulated with Montanide ISA 50V2 adjuvant and administered twice subcutaneously (2 ml per dose) at an interval of 4 weeks. All groups were challenged with a virulent homologous cell-cultured E. ruminantium inoculated via the intra-venous route on day 56. The primary variable of efficacy was measured by the percentage survival rate or mortality between the Controls and Vaccine Groups.Three vaccine formulations (BEI/Percoll (Group 3), BEI/PEG (Group 4), BPL/Percoll, (Group 1) had a significantly higher percent of animal surviving challenge compared to the unvaccinated control (p-values 0.001, 0.035, 0.030, respectively). The highest number of survivors was obtained in Group 3 BEI/Percoll; 10/11 (91%). Groups 4 (BEI/PEG) and Group 1 (BPL/Percoll) produced similar percentage of survivals of 64%. In contrast, the lowest survival rate of 50% was observed in Group 2 (BPL/PEG) which was numerically different but not significantly different from the unvaccinated control which had an 18% survival rate (2/11).The inactivated vaccine using BEI or BPL as inactivating agents blended with ISA 50 adjuvant induced protective immunity against challenge. The BEI/Percoll (Group 3) vaccination regimen was most efficacious against a lethal heartwater challenge as it significantly protected sheep against mortality which is the most important aspect of heartwater infections. Future work should be directed towards improvement of this vaccine formulation especially from the down-stream processing point of view as the percoll method is not scalable for commercialization purposes.

Susceptibility of Palmer amaranth (Amaranthus palmeri) to herbicides in accessions collected from the North Carolina Coastal Plain

AbstractPalmer amaranth (Amaranthus palmeri S. Watson) populations resistant to acetolactate synthase (ALS)-inhibiting herbicides and glyphosate are fairly common throughout the state of North Carolina (NC). This has led farm managers to rely more heavily on herbicides with other sites of action (SOA) for A. palmeri control, especially protoporphyrinogen oxidase and glutamine synthetase inhibitors. In the fall of 2016, seeds from A. palmeri populations were collected from the NC Coastal Plain, the state’s most prominent agricultural region. In separate experiments, plants with 2 to 4 leaves from the 110 populations were treated with field use rates of glyphosate, glufosinate-ammonium, fomesafen, mesotrione, or thifensulfuron-methyl. Percent visible control and survival were evaluated 3 wk after treatment. Survival frequencies were highest following glyphosate (99%) or thifensulfuron-methyl (96%) treatment. Known mutations conferring resistance to ALS inhibitors were found in populations surviving thifensulfuron-methyl application (Ala-122-Ser, Pro-197-Ser, Trp-574-Leu, and/or Ser-653-Asn), in addition to a new mutation (Ala-282-Asp) that requires further investigation. Forty-two populations had survivors after mesotrione application, with one population having 17% survival. Four populations survived fomesafen treatment, while none survived glufosinate. Dose–response studies showed an increase in fomesafen needed to kill 50% of two populations (LD50); however, these rates were far below the field use rate (less than 5 g ha−1). In two populations following mesotrione dose–response studies, a 2.4- to 3.3-fold increase was noted, with LD90 values approaching the field use rate (72.8 and 89.8 g ha−1). Screening of the progeny of individuals surviving mesotrione confirmed the presence of resistance alleles, as there were a higher number of survivors at the 1X rate compared with the parent population, confirming resistance to mesotrione. These data suggest A. palmeri resistant to chemistries other than glyphosate and thifensulfuron-methyl are present in NC, which highlights the need for weed management approaches to mitigate the evolution and spread of herbicide-resistant populations.

'PARAMEDIC-2: Big study, small result'.

The PARAMEDIC-2 trial demonstrated that the use of adrenaline compared with placebo in out-of-hospital cardiac arrest (OHCA) resulted in a small increase in 30-day survival, but was associated with a higher number of survivors with severe neurological impairment. These findings received a lot of attention, and generated a widespread discussion about the role of adrenaline in cardiac arrest. In this point of view, we aim to place the PARAMEDIC-2 results in the right perspective by comparing the relative effect of adrenaline to other determinants of cerebral blood flow.

The pattern and characteristics of sexual assault perpetrators and survivors managed at a sexual assault referral centre in Lagos.

BackgroundThere has presumably been an increase in cases of sexual assault in Nigeria; however, accurate data on the characteristics of the survivors and perpetrators are not readily available in most cases.AimTo report the pattern and characteristics of sexual assault perpetrators and survivors managed at the Mirabel Centre, Lagos State University Teaching Hospital (LASUTH), Ikeja – a three-year review.MethodsA retrospective audit carried out in the sexual assault referral centre (SARC) – Mirabel Centre, LASUTH, Lagos State, Nigeria. A total of 2160 case files from July 2013 to January 2017 were assessed for age group of survivors and gender, among others.ResultsA total of 2160 cases were analysed. The mean age of survivors was 13.9 (± 4.4) years with the 11–20 years age group having the highest number of survivors (48.4%) and the 0–10 years age group having 35.9% of survivors. Majority of the survivors (97.7%) were female. The majority of the perpetrators were known to the survivors with 10.3% being family members. Defilement (71.6%) was the most reported type of assault at the centre with rape (20.3%) being the second most common. The majority of the referrals to the centre were from the police (76.7%), while self-referrals made up 8% of referrals.ConclusionMinors and adolescents formed the majority of the survivors. Defilement was the most reported form of sexual violence. There needs to be special intervention for better monitoring and protection of minors and youths against sexual assault. The establishment of more sexual assault referral centres in Nigeria will increase reportage and treatment of survivors.

Assessing Student Success in a Project-Based Learning Biology Course at a Community College

Project-based learning (PBL) and traditional teaching methods represent two opposing pedagogical philosophies. A PBL Biology lab course was designed and taught concurrently with its traditional counterpart to compare student success. The PBL course investigated the effects of simulated acid rain on the rate of adaptation in two species that differ in complexity and rate of reproduction, Caenorhabditis elegans and Paramecium caudatum. The species with the highest number of survivors at the end of six week's exposure to acid rain was deemed to have adapted best. In two out of three semesters students concluded that P. caudatum responded to acid rain with the greatest rate of adaptation. Student success was compared between both types of courses using four methods of assessment: student academic performance, retention rate, transfer rate to four-year institutions, and participation points. The results of two methods of assessment out of four were statistically significantly higher in the PBL courses. Considering that the other two methods of assessment did not favor traditional pedagogy, but produced comparable student success in the traditional and PBL courses, it can be concluded that PBL pedagogy is a highly desirable alternative to traditional teaching methods in biology courses at the community college level.

Multidisciplinary assessment of post-Ebola sequelae in Guinea (Postebogui): an observational cohort study

The high number of survivors from the 2013-16 west African outbreak of Ebola virus disease (EVD) has raised several new issues: long-term clinical complications, psychosocial consequences, risks of EVD reactivation, and secondary transmission due to viral persistence in body fluids. We aimed to assess long-term clinical, psychosocial, and viral outcomes in EVD survivors in Guinea. In this multidisciplinary observational cohort study, we recruited patients aged 1 year or more in four sites in Guinea (Donka National Hospital, Conakry; Macenta Prefectoral Hospital, Macenta; N'zérékoré Regional Hospital, N'zérékoré; and Forécariah Prefectoral Hospital, Forécariah) following discharge from any Ebola treatment centre in Guinea. Eligible patients had had laboratory-confirmed EVD and had then been declared clear of the virus in the blood. All consenting patients were included, with no exclusion criteria. Trained clinicians assessed patients at enrolment to the cohort, recording clinical symptoms and signs of depression. We did routine blood examinations and examined viral persistence in body fluids using RT-PCR. We did psychological evaluations using questionnaires developed for different age groups. Follow-up is planned to 2 years, and here we present findings at enrolment. Between March 23, 2015, and July 11, 2016, we recruited 802 patients, of whom 360 (45%) were male, 442 (55%) were female; 158 (20%) were younger than 18 years. The median age was 28·4 years (range 1·0-79·9, IQR 19·4-39·8). The median delay after discharge was 350 days (IQR 223-491). The most frequent symptoms were general symptoms (324 [40%] patients), musculoskeletal pain (303 [38%]), headache (278 [35%]), depression (124 [17%] of 713 responses), abdominal pain (178 [22%]), and ocular disorders (142 [18%]). More adults than children had at least one clinical symptom (505 [78%] vs 101 [64%], p<0·0003), ocular complications (124 [19%] vs 18 [11%], p=0·0200), or musculoskeletal symptoms (274 [43%] vs 29 [18%], p<0·0001). A positive RT-PCR in semen was found in ten (5%) of 188 men, at a maximum of 548 days after disease onset. 204 (26%) of 793 patients reported stigmatisation. Ocular complications were more frequent at enrolment than at discharge (142 [18%] vs 61 [8%] patients). Post-EVD symptoms can remain long after recovery and long-term viral persistence in semen is confirmed. The results justify calls for regular check-ups of survivors at least 18 months after recovery. INSERM/Reacting, the French Ebola Task Force, and Institut de Recherche pour le Développement.

The establishment of a standard operation procedure for psychiatric service after an earthquake

This study presents information on the design and creation of a standard operation procedure (SOP) for psychiatric service after an earthquake. The strategies employed focused on the detection of survivors who developed persistent psychiatric illness, particularly post-traumatic stress and major depressive disorders. In addition, the study attempted to detect the risk factors for psychiatric illness. A Disaster-Related Psychological Screening Test (DRPST) was designed by five psychiatrists and two public health professionals for rapidly and simply interviewing 4,223 respondents within six months of the September 1999 Chi-Chi earthquake. A SOP was established through a systemic literature review, action research, and two years of data collection. Despite the limited time and resources inherent to a disaster situation, it is necessary to develop an SOP for psychiatric service after an earthquake in order to assist the high number of survivors suffering from subsequent psychiatric impairment.

Search towards an insight for comparative anti-tumour effects of Wrightia tomentosa leaf &amp; bark in ehrlich ascites carcinoma bearing mice

SUMMARY In the present study, the ethanolic leaf and bark extract of Wrightia tomentosa were tested forcomparative in vivo antitumour properties against Ehrlich ascites carcinoma (EAC) tumourbearing mice at 100 and 200 mg/kg body weight doses given orally once daily for 16 days. TheEAC mice receiving 100 and 200 mg/kg ethanolic leaf and bark extract showed a dose dependentelevation in tumour – free survival and a highest number of survivors were observed at 200 mg/kg for leaf extract of ethanol, which was considered as an optimum dose for its anti neoplasticaction. The Median survival time for this dose was approximately 44 days when compared with23 days of non-drug treated controls. The results indicate that the administration of leaf extractnot only increased the survival of animals with ascites tumour and reduced packed cell volumeand viable tissue cell count, but also altered many hematological parameters changed duringtumour progression, indicating the potent antitumour nature of leaf extract than the bark extract.Statistical analysis also reveals that the leaf extract showed highly significant anti tumour potency(p < 0.001) when compared with control.Key words: Wrightia tomentosa; Ethanol extract; Leaf, Bark; Ehrlich ascites carcinoma (EAC);antitumour

Evaluation of the Antineoplastic Activity of Guduchi (Tinospora cordifolia) in Ehrlich Ascites Carcinoma Bearing Mice

The anticancer activity of dichloromethane extract of guduchi [Tinospora cordifolia (Willd.) Miers ex Hook. F. & Thoms. Family: Menispermaceae (TCE)] in the mice transplanted with Ehrlich ascites carcinoma (EAC) was investigated. The EAC mice receiving 25, 30, 40, 50 and 100 mg/kg, TCE showed a dose dependent elevation in tumor-free survival and a highest number of survivors were observed at 50 mg/kg TCE, which was considered as an optimum dose for its neoplastic action. The average survival time (AST) and median survival time (MST) for this dose were approximately 56 and 55 d, respectively when compared with 19 d of non-drug treated controls. Administration of 50 mg/kg TCE resulted in 100% long-term survivors (up to 90 d). An attempt was also made to evaluate the effectiveness of TCE in the various stages of tumor development, where 50 mg/kg TCE was administered intraperitoneally after 1, 3, 6, 9, 12 or 15 d of tumor inoculation and these days have been arbitrarily designated as stage I, II, III, IV or V, respectively for reasons of clarity. The greatest anticancer activity was recorded for stage I, II and III where number of long term survivors (LTS) was approximately 33, 25 and 17%, respectively. However, treatment of mice at stage IV and V did not increase LTS, despite an increase in AST and MST. The EAC mice receiving 50 mg/kg TCE showed a time dependent depletion in the glutathione (GSH) activity up to 12 h post-treatment and marginal elevation thereafter. This depletion in GSH was accompanied by a drastic elevation in lipid peroxidation (LPx) and a maximum elevation in LPx was observed at 6 h that declined gradually thereafter. TCE exerted cytotoxic effect on tumor cells by reducing the GSH concentration and increase in LPx simultaneously.

Fruit Extract of Aegle marmelos Protects Mice Against Radiation-Induced Lethality

The radioprotective effect of a hydroalcoholic extracted material from the fruit of Aegle marmelos (AME) was studied in mice exposed to different doses of gamma radiation. The optimum dose for radioprotection was determined by administering 0, 5, 10, 20, 40, or 80 mg/kg body weight of AME intraperitoneally (ip) once daily, consecutively for 5 days before exposure to 10 Gy of gamma radiation. A total of 20 mg/kg of AME for 5 consecutive days before irradiation was found to afford maximum protection as evidenced by the highest number of survivors after 30 days postirradiation. Animals from all groups were monitored for 30 days postirradiation for development of symptoms of radiation sickness and mortality. Treatment of mice with AME before exposure to different doses of gamma radiation reduced the severity of symptoms of radiation sickness and mortality with all exposure doses. This was accompanied by an increase in number of survivors in the AME + irradiation group when compared with the concurrent sterile physiological saline (SPS) + irradiation group. AME pretreatment protected mice against the gastrointestinal as well as bone marrow deaths, as evidenced by the greater number of survivors on day 10 or 30, respectively. LD50/30 was found to be 8.2 Gy for the SPS + irradiation group, while it was 8.8 Gy for AME + irradiation. The dose-reduction factor (DRF) was found to be 1.1 for AME + irradiation group. The acute toxicity study of AME showed that it was nontoxic up to a dose of 6 g/kg body weight, the highest drug dose that could be administered. Irradiation of animals resulted in a dose-dependent elevation in lipid peroxidation in liver, kidney, stomach, and intestine of mice. Conversely, GSH concentration declined in a dose-dependent manner. Treatment of animals with AME before irradiation caused a significant decrease in the lipid peroxidation accompanied by a significant elevation in the GSH concentration in liver, kidney, stomach, and intestine of mice determined at 31 days postirradiation.

The evaluation of the radioprotective effect of chyavanaprasha (an ayurvedic rasayana drug) in mice exposed to lethal dose of gamma-radiation: a preliminary study.

The effect of various doses of 50% ethanolic extract of chyavanaprasha (an Ayurvedic rejuvenating herbal preparation) was studied on the survival of mice exposed to 10 Gy of gamma-radiation. Treatment with chyavanaprasha, consecutively for fi ve days before irradiation, delayed symptoms of radiation sickness and onset of mortality when compared with the non-drug treated irradiated controls. All doses of chyavanaprasha provided a significant protection against gastrointestinal (GI) death (death of animals within 10 days after exposure to radiation), however, highest protection against GI death was observed for 15 mg/kg chyavanaprasha. Chyavanaprasha also provided a significant protection against the bone marrow death after 10 to 40 mg/kg. However, the best protection was seen for 15 mg/kg, where the highest number of survivors was observed at the end of 30 days post-irradiation. The drug was non-toxic up to a dose of 6 g/kg b. wt., the highest drug dose that could be tested. Our study demonstrates that chyavanaprasha can provide good radioprotection at a very low non-toxic dose.

Evaluation of the radioprotective action of geriforte in mice exposed to different doses of gamma-radiation.

The effect of 5, 10, 20, 40 and 80 mg/kg b. wt. of hydroalcoholic extract of geriforte (an Ayurvedic herbal medicine) administered intraperitoneally was studied on the radiation-induced mortality in mice exposed to 10 Gy of gamma-radiation. Treatment of mice with different doses of geriforte consecutively for 5 days before irradiation delayed the onset of mortality and reduced the symptoms of radiation sickness when compared with the non-drug treated irradiated controls. A maximum protection was observed for 10 mg/kg geriforte, where a highest number of survivors were reported by 30 days post-irradiation and further experiments were carried out using this dose of geriforte. The mice were treated with 10 mg/kg b. wt. geriforte or double distilled water (DDW) and exposed to 7, 8, 9, 10 and 11 Gy of gamma radiation and observed for the induction of symptoms of radiation sickness and mortality up to 30 days post-irradiation. The geriforte treatment protected the mice against the GI death as well as bone marrow deaths and the dose reduction factor (DRF) was found to be 1.14. Toxicity study showed that geriforte was non-toxic up to a dose of 4250 mg/kg, where no drug-induced mortality was observed. The LD50 dose of geriforte was found to be 4750 mg/kg b. wt. To understand the mechanism of action of geriforte, free radical scavenging activity of the drug was evaluated. Geriforte was found to scavenge *OH, O2*- ABTS*+ and NO* in a dose-dependent manner. Our study demonstrates that geriforte is a good radioprotective agent and the optimum protective dose of 10 mg/kg was 1/475th of the LD50 dose.

Treatment of mice with a herbal preparation (mentat) protects against radiation-induced mortality.

The effect of various doses (0, 5, 10, 20, 40, 80, 100, 120 and 160 mg/kg b. wt.) of 50% ethanolic extract of mentat (a herbal preparation) was studied on the survival of mice exposed to 10 Gy of gamma-radiation. Treatment of mice with different doses of mentat consecutively for fi ve days before irradiation delayed the onset of mortality and reduced the symptoms of radiation sickness when compared with the non-drug treated irradiated controls. Most of the doses of mentat provided protection against the gastrointestinal (GI) death, however, the highest protection against GI death was observed for 80 mg/kg mentat. This was also true for bone marrow deaths, where the highest number of survivors were observed at 30 days post-irradiation in this group (i.e. 80 mg/kg) when compared with the other doses of mentat. The evaluation of acute toxicity showed that mentat was non-toxic up to a dose of 1.5 g/kg b. wt., where no drug-induced mortality was observed. The LD50 dose of mentat was found to be 1.75 g/kg b. wt. Our study demonstrates that mentat can provide good radioprotection at a dose of 80 mg/kg, which is far below its toxic dose.

Evaluation of the radioprotective effect of Ageratum conyzoides Linn. extract in mice exposed to different doses of gamma radiation

The effect of various doses (0, 25, 50, 75, 100, 125, 150, 300, 600 and 900 mg kg(-1)) of the alcoholic extract of the plant Ageratum conyzoides Linn. (ACE), on the alteration of radiation-induced mortality in mice exposed to 10 Gy of gamma radiation was studied. The acute toxicity studies showed that the drug was non-toxic up to a dose of 3000 mg kg(-1), the highest dose that could be tested for acute toxicity. Administration of ACE resulted in a dose-dependent decline in radiation-induced mortality up to a dose of 75 mg kg(-1), the dose at which the highest number of survivors (70.83%) was observed. Thereafter, the number of survivors declined with increasing doses of ACE and a nadir was reached at 900 mg kg(-1) ACE. Since the number of survivors was highest for 75 mg kg(-1) ACE, this was considered the optimum dose for radioprotection and used in further studies in which mice were treated with 75 mg kg(-1) ACE before exposure to 6, 7, 8, 9, 10 and 11 Gy of gamma radiation. The treatment of mice with 75 mg kg(-1) ACE reduced the severity of symptoms of radiation sickness and mortality at all exposure doses, and a significant increase in survival was observed compared with the non-treated irradiated group. The ACE treatment effectively protected mice against the gastrointestinal as well as bone marrow related death, as revealed by the increased number of survivors at all irradiation doses. The dose reduction factor was found to be 1.3. To understand the mechanism of action, various doses of ACE were evaluated for their in-vitro scavenging action on 1,1-diphenyl-2-picrylhydrazyl (DPPH), a chemically stable free radical. ACE was found to scavenge DPPH radicals in a concentration-dependent manner, indicating that the radioprotection afforded by ACE may be in part due to the scavenging of reactive oxygen species induced by ionizing radiation.

Effect of abana (a herbal preparation) on the radiation-induced mortality in mice

The effect of various doses (0, 5, 10, 20, 40 and 80 mg/kg body weight) of 50% ethanolic extract of abana, a traditional herbal preparation, widely used in India for the treatment of heart ailments, was studied on the radiation-induced mortality in mice exposed to 10 Gy of γ-radiation. Treatment of mice with different doses of abana delayed the onset of mortality and reduced the symptoms of radiation sickness as compared to the irradiated controls. All doses of abana provided protection against the gastrointestinal (GI) death, however, the highest protection against GI death was observed for 20 mg/kg abana. Pretreatment of mice with 20 mg/kg abana provided the best protection as evidenced by the highest number of survivors after 30 days post-irradiation in this group when compared to the other doses of abana. Acute toxic studies revealed that the abana was non-toxic up to a dose of 1.6 g/kg, where no drug-induced mortality was observed. The LD 50 dose of abana was found to be 1.8 g/kg body weight. Our study demonstrates the ability of abana as a good radioprotective agent and the optimum protective dose of abana was 1/90 of its LD 50 dose.

Cystone, an ayurvedic herbal drug imparts protection to the mice against the lethal effects of gamma-radiation: a preliminary study.

The effect of 5, 10, 20, 40, 60, 80, 100, 120, and 160 mg/kg body weight (b.wt.) of aqueous extract of cystone (an ayurvedic herbal medicine) administered intraperitoneally was studied on the radiation-induced mortality in mice exposed to 10 Gy of gamma-radiation. Treatment of mice with different doses of cystone, consecutively for five days before irradiation, delayed the onset of mortality and reduced the symptoms of radiation sickness when compared with the non-drug treated irradiated controls. The pretreatment of mice with different doses of cystone before exposure to 10 Gy of gamma-radiation resulted in a dose-dependent elevation in the survival up to 40 mg/kg b.wt., where the highest number of survival (55.55%) was observed by 30 days post irradiation, when compared with the 10 Gy irradiated control (6.66%). Thereafter, the number of survivors declined and reached a nadir at 160 mg/kg, where no survivors could be observed. The optimum protection against irradiation was observed for 40 mg/kg cystone, where the highest number of survivors were reported by 30 days post irradiation and it was 8.34-fold greater than that of the irradiated control group.

The evaluation of the radioprotective effect of Triphala (an ayurvedic rejuvenating drug) in the mice exposed to gamma-radiation.

The effect of 0, 5, 6.25, 10, 12.5, 20, 25, 40, 50 and 80 mg/kg b. wt. of aqueous extract of triphala (an Ayurvedic herbal medicine) administrered intraperitoneally was studied on the radiation-induced mortality in mice exposed to 10 Gy of gamma-radiation. Treatment of mice with different doses of triphala consecutively for five days before irradiation delayed the onset of mortality and reduced the symptoms of radiation sickness when compared with the non-drug treated irradiated controls. The highest protection against GI (gastrointestinal) death was observed for 12.5 mg/kg triphala, where a highest number of survivors were reported up to 10 days post-irradiation. While 10 mg/kg triphala i.p. provided the best protection as evidenced by the highest number of survivors after 30 days post-irradiation in this group when compared with the other doses of triphala. Toxicity study showed that triphala was non-toxic up to a dose of 240 mg/kg, where no drug-induced mortality was observed. The LD50 dose i.p. of triphala was found to be 280 mg/kg b. wt. Our study demonstrates the ability of triphala as a good radioprotective agent and the optimum protective dose of triphala was 1/28 of its LD50 dose.

Survival of Escherichia coli O157:H7 in frozen foods: impact of the cold shock response

The survival of Escherichia coli O157:H7 strains in both frozen foods and trypticase soy broth (TSB) was investigated following cold shocking at 10°C for 1.5 h. Using both trypticase soy agar (TSA) and violet red bile agar (VRBA) as recovery media, it was demonstrated that survival levels between cold shocked (CS) and non-cold shocked (NS) E. coli in ground beef or pork were not significantly different ( P≤0.05). In contrast, cold shocking E. coli in either milk, whole egg or sausage resulted in a significant( P≤0.05) enhancement in survival. For milk, survival levels of CS E. coli, by 28 days of frozen storage, were 1.89 and 1.66 log 10 cfu/ml higher on TSA and VRBA, respectively, when compared to NS cells. In egg these values were 0.64 and 1.31, while in sausage, values of 0.74 and 1.19 were obtained. In TSB (pH 7) survival of CS E. coli for some strains was about 3 log 10 cfu/ml higher when compared to NS cells. Acidification of TSB (pH 5), however, appeared to negate the protective effects of the cold shock treatment. In milk, increasing the differential between the growth and cold shock temperatures resulted in higher numbers of survivors. In this regard the growth-cold shock temperature protocol giving optimum protection was 37–10°C. In contrast, growth of E. coli at 20°C followed by cold shocking at 10°C did not result in any significant freeze protection. In addition, increased protection due to cold shocking was correlated with the appearance of a novel protein appearing at p I 4.8 following isoelectric focusing analysis, thus demonstrating an alteration of protein synthesis.

Osmotic stress on dilution of acid injuredEscherichia coliO157:H7

To determine surviving numbers of Escherichia coli from cultures or food systems, dilution with 0.1% peptone is regularly used. Higher numbers of survivors could be obtained from an acid-treated culture if 0.5 mol l-1 sucrose was added to the 0.1% peptone. Sorbitol, glucose or sodium chloride, but not glycerol, could be used in place of sucrose. Using electron microscopy distinct differences could be seen between acid-treated and untreated cells. The osmolarity of the diluents ranged from 5 to 500 mosmol kg-1 H2O for the 0.5 mol l-1 sugar or glycerol solutions, to about 1000 mosmol kg-1 H2O for the salt solution. Maximum recovery diluent has an osmolarity of about 300 mosmol kg-1 H2O and resulted in recovery of similar numbers of injured cells as a 0.5 mol l-1 solution of sugar in 0.1% peptone. Taking into account the observed damage to acid-treated cells and the differences in osmolarity of the diluents, it is likely that dilution in 0.1% peptone imposed additional stress on the acid-injured cells which caused further cell damage. Dilution in a more osmotically stable solution alleviated this osmotic stress.

An experimental approach to the effects of varying recruitment strategy and food intake on early reproductive traits in a brooding Mediterranean polychaete

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 164:147-156 (1998) - doi:10.3354/meps164147 An experimental approach to the effects of varying recruitment strategy and food intake on early reproductive traits in a brooding Mediterranean polychaete D. Martin1,*, J. H. Cha2, C. Nozais3, M. Bhaud3 1Centre d'Estudis Avançats de Blanes (CSIC), Camí de Santa Bàrbara s/n, E-17300 Blanes (Girona), Spain 2KORDI (Korea Ocean Research and Development Institute), Biological Oceanography Division, ANSAN PO Box 29, Seoul Kr-425-600, Korea 3Laboratoire Arago, Observatoire Océanologique de Banyuls, Université P. et M. Curie (Paris VI), CNRS, URA 117, F-66651 Banyuls-sur-Mer cedex, France *E-mail: dani@ceab.csic.es We examined the effects of reproductive strategy and food intake on the early life history traits of a Mediterranean population of Eupolymnia nebulosa, a deposit-feeding, tubicolous polychaete. In the Mediterranean E. nebulosa are brood-caring, maturity is attained at 2 yr and up to 4 cocoons are produced per female each year, which reduces larval dispersal. In the Atlantic E. nebulosa are free-spawning, they mature in their first year of life and they produce larger offspring, which are released simultaneously. An experimental population grown from spawn collected in the Mediterranean was divided into 2 groups on the basis of the number of tentacles. These 2 groups were taken to simulate the 2 reproductive strategies: worms with 2, 3, 4 and 5 tentacles at the start for the Mediterranean strategy and worms with 3 tentacles at the start for the Atlantic strategy. They were further subdivided and treated with low- and high-energy diets. After 3 mo the only significant difference was a high number of survivors in the group used to simulate Mediterranean recruitment. After 12 mo the high-energy diet increased survival, mean number of tentacles per individual, total tentacles and total worm biomass, and reduced generation time to 1 yr. Although fecundity of these early breeders was lower than that of 2 yr old worms from both laboratory and field populations, this can be entirely attributed to differences in maternal body size. Based on our experimental results, the ecological implications of the reproductive strategy of Mediterranean E. nebulosa are discussed and a new model of resource allocation is proposed for their populations. Terebellidae · Eupolymnia nebulosa · Recruitment strategy · Food intake · Early reproductive traits · NW Mediterranean Full text in pdf format PreviousNextExport citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 164. Publication date: April 09, 1998 Print ISSN:0171-8630; Online ISSN:1616-1599 Copyright © 1998 Inter-Research.