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1.
Nanoscale ; 15(36): 14782-14789, 2023 Sep 21.
Article in English | MEDLINE | ID: mdl-37548923

ABSTRACT

Exchange coupling in a model core-shell system is demonstrated as a step on the path to 3d exchange spring magnets. Employing a model system of Ni@CoFe2O4, high quality core-shell nanoparticles were fabricated using a simple two-step method. The microstructural quality was validated using TEM, confirming a well-defined interface between the core and the shell. A strongly temperature dependent two-phase magnetic hysteresis loop was measured, wherein an analysis of step heights indicates coupling of roughly 50% between the core and the shell. Element-specific XMCD hysteresis confirms the presence of exchange coupling, suppressing the superparamagnetism of the Ni core at room temperature, and reaching a coercivity of >6 kOe at 80 K. These results provide a pathway to the development of heterostructured metal-oxide exchange coupled nanoparticles with improved maximum energy product.

2.
Front Microbiol ; 14: 1208301, 2023.
Article in English | MEDLINE | ID: mdl-37426014

ABSTRACT

Introduction: Dirofilariasis, including heartworm disease, is a major emergent veterinary parasitic infection and a human zoonosis. Currently, experimental infections of cats and dogs are used in veterinary heartworm preclinical drug research. Methods: As a refined alternative in vivo heartworm preventative drug screen, we assessed lymphopenic mouse strains with ablation of the interleukin-2/7 common gamma chain (γc) as susceptible to the larval development phase of Dirofilaria immitis. Results: Non-obese diabetic (NOD) severe combined immunodeficiency (SCID)γc-/- (NSG and NXG) and recombination-activating gene (RAG)2-/-γc-/- mouse strains yielded viable D. immitis larvae at 2-4 weeks post-infection, including the use of different batches of D. immitis infectious larvae, different D. immitis isolates, and at different laboratories. Mice did not display any clinical signs associated with infection for up to 4 weeks. Developing larvae were found in subcutaneous and muscle fascia tissues, which is the natural site of this stage of heartworm in dogs. Compared with in vitro-propagated larvae at day 14, in vivo-derived larvae had completed the L4 molt, were significantly larger, and contained expanded Wolbachia endobacteria titres. We established an ex vivo L4 paralytic screening system whereby assays with moxidectin or levamisole highlighted discrepancies in relative drug sensitivities in comparison with in vitro-reared L4 D. immitis. We demonstrated effective depletion of Wolbachia by 70%-90% in D. immitis L4 following 2- to 7-day oral in vivo exposures of NSG- or NXG-infected mice with doxycycline or the rapid-acting investigational drug, AWZ1066S. We validated NSG and NXG D. immitis mouse models as a filaricide screen by in vivo treatments with single injections of moxidectin, which mediated a 60%-88% reduction in L4 larvae at 14-28 days. Discussion: Future adoption of these mouse models will benefit end-user laboratories conducting research and development of novel heartworm preventatives via increased access, rapid turnaround, and reduced costs and may simultaneously decrease the need for experimental cat or dog use.

3.
Anaesthesia ; 75(11): 1469-1475, 2020 11.
Article in English | MEDLINE | ID: mdl-32463487

ABSTRACT

Anaphylaxis in pregnancy is a rare but severe complication for both mother and infant. Population-based data on anaphylaxis in pregnancy are lacking from mainland European countries. This multinational study presents the incidence, causative agents, management and maternal and infant outcomes of anaphylaxis in pregnancy. This descriptive multinational study used a combination of retrospective (Finnish medical registries) and prospective population-based studies (UK, France, Belgium and the Netherlands) to identify cases of anaphylaxis. Sixty-five cases were identified among 4,446,120 maternities (1.5 per 100,000 maternities; 95%CI 1.1-1.9). The incidence did not vary between countries. Approximately three-quarters of reactions occurred at the time of delivery. The most common causes were antibiotics in 27 women (43%), and anaesthetic agents in 11 women (17%; including neuromuscular blocking drugs, 7), which varied between countries. Anaphylaxis had very poor outcomes for one in seven mothers and one in seven babies; the maternal case fatality rate was 3.2% (95%CI 0.4-11.0) and the neonatal encephalopathy rate was 14.3% (95%CI 4.8-30.3). Across Europe, anaphylaxis related to pregnancy is rare despite having a multitude of causative agents and different antibiotic prophylaxis protocols.


Subject(s)
Anaphylaxis/epidemiology , Pregnancy Complications/epidemiology , Adult , Europe/epidemiology , Female , Humans , Incidence , Pregnancy , Prospective Studies , Retrospective Studies
4.
Behav Brain Res ; 363: 191-198, 2019 05 02.
Article in English | MEDLINE | ID: mdl-30735761

ABSTRACT

The prefrontal cortex (PFC) undergoes protracted postnatal development such that its structure and behavioural function may be profoundly altered by environmental factors. Here we investigate the effect of lactational dietary manipulations on novel object recognition (NOR) learning and PFC monoamine neurotransmitter metabolism in early adolescent rats. To this end, Wistar rat dams were fed a high caloric cafeteria diet (CD) during lactation and resultant 24-26 day old offspring exposed to NOR testing and simultaneous PFC dopamine and serotonin metabolism measurement. In the second NOR choice trial where one familiar and one novel object were presented controls explored the novel preferentially to the familiar object both after a 5 min (P < 0.001) or 30 min (P < 0.05) inter-trial intervals (ITI). By contrast, offspring from dams fed on lactational CD failed to show any significant preference for the novel object at either time point. Compared with chow fed controls, their average exploration ratio of the novel object was lower after the 5 min ITI (P < 0.05). Following a 60 min ITI, neither CD nor control offspring showed a preference for the novel object. PFC dopamine metabolism was significantly reduced in the CD group (P < 0.001), whereas serotonin metabolism was increased (P < 0.001). These results suggest that an obesogenic lactational diet can have a detrimental impact on cognition in adolescent offspring associated with aberrant PFC serotonin and dopamine metabolism.


Subject(s)
Diet, High-Fat/adverse effects , Exploratory Behavior/drug effects , Maternal Nutritional Physiological Phenomena/physiology , Age Factors , Animals , Biogenic Monoamines/metabolism , Cognition/drug effects , Cognition/physiology , Diet , Dopamine/metabolism , Exploratory Behavior/physiology , Female , Lactation , Learning , Male , Prefrontal Cortex/drug effects , Prefrontal Cortex/metabolism , Prefrontal Cortex/physiology , Pregnancy , Prenatal Exposure Delayed Effects/physiopathology , Rats , Rats, Wistar
5.
Ann Oncol ; 29(5): 1108-1119, 2018 05 01.
Article in English | MEDLINE | ID: mdl-29659677

ABSTRACT

Human epidermal growth factor receptor 2 (HER2) is an oncogenic driver, and a well-established therapeutic target in breast and gastric cancers. Using functional and genomic analyses of patient-derived xenografts, we previously showed that a subset (approximately 5%) of metastatic colorectal cancer (CRC) tumors is driven by amplification or mutation of HER2. This paper reviews the role of HER2 amplification as an oncogenic driver, a prognostic and predictive biomarker, and a clinically actionable target in CRC, considering the specifics of HER2 testing in this tumor type. While the role of HER2 as a biomarker for prognosis in CRC remains uncertain, its relevance as a therapeutic target has been established. Indeed, independent studies documented substantial clinical benefit in patients treated with biomarker-driven HER2-targeted therapies, with an impact on response rates and duration of response that compared favorably with immunotherapy and other examples of precision oncology. HER2-targeted therapeutic strategies have the potential to change the treatment paradigm for a clinically relevant subgroup of metastatic CRC patients.


Subject(s)
Antineoplastic Agents, Immunological/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Colorectal Neoplasms/therapy , Neoplasm Recurrence, Local/prevention & control , Receptor, ErbB-2/antagonists & inhibitors , Antineoplastic Agents, Immunological/pharmacology , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Biomarkers, Tumor/analysis , Biomarkers, Tumor/antagonists & inhibitors , Biomarkers, Tumor/genetics , Biopsy , Chemotherapy, Adjuvant/methods , Clinical Trials as Topic , Colorectal Neoplasms/genetics , Colorectal Neoplasms/mortality , Colorectal Neoplasms/pathology , Disease-Free Survival , Gene Amplification , Genetic Testing , Humans , Molecular Targeted Therapy/methods , Neoadjuvant Therapy/methods , Neoplasm Recurrence, Local/genetics , Neoplasm Recurrence, Local/pathology , Precision Medicine/methods , Prognosis , Progression-Free Survival , Receptor, ErbB-2/analysis , Receptor, ErbB-2/genetics
6.
BJOG ; 125(8): 965-971, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29193647

ABSTRACT

OBJECTIVE: The aim of this study was to estimate the incidence of anaphylaxis in pregnancy and describe the management and outcomes in the UK. DESIGN: A population-based descriptive study using the UK Obstetric Surveillance System (UKOSS). SETTING: All consultant-led maternity units in the UK. POPULATION: All pregnant women who had anaphylaxis between 1 October 2012 and 30 September 2015. Anaphylaxis was defined as a severe, life-threatening generalised or systemic hypersensitivity reaction. METHODS: Prospective case notification using UKOSS. MAIN OUTCOME MEASURES: Maternal mortality, severe maternal morbidity, neonatal mortality and severe neonatal morbidity. RESULTS: There were 37 confirmed cases of anaphylaxis in pregnancy, giving an estimated incidence of 1.6 (95% CI: 1.1-2.2) per 100 000 maternities. Four cases of anaphylaxis were in women with known penicillin allergies: two received co-amoxiclav and two cephalosporins. Twelve women had anaphylaxis following prophylactic use of antibiotics at the time of a caesarean delivery. Prophylactic use of antibiotics for Group B streptococcal infection accounted for anaphylaxis in one woman. Two women died (5%), 14 (38%) women were admitted to intensive care and seven women (19%) had one or more additional severe maternal morbidities, which included three haemorrhagic events, two cardiac arrests, one thrombotic event and one pneumonia. No infants died; however, in those infants whose mother had anaphylaxis before delivery (n = 18) there were seven (41%) neonatal intensive care unit admissions, three preterm births and one baby was cooled for neonatal encephalopathy. CONCLUSIONS: Anaphylaxis is a rare severe complication of pregnancy and frequently the result of a reaction to antibiotic administration. This study highlights the seriousness of the outcomes of this condition for the mother. The low incidence is reassuring given the large proportion of the pregnant population that receive prophylactic antibiotics during delivery. TWEETABLE ABSTRACT: Anaphylaxis is a rare severe complication of pregnancy and frequently the result of a reaction to antibiotic administration.


Subject(s)
Anaphylaxis/mortality , Population Surveillance , Pregnancy Complications/mortality , Adult , Female , Humans , Incidence , Infant, Newborn , Maternal Mortality , Perinatal Mortality , Pregnancy , Pregnancy Complications/immunology , Pregnancy Outcome , Prospective Studies , United Kingdom/epidemiology , Young Adult
7.
Ann Oncol ; 28(6): 1352-1358, 2017 Jun 01.
Article in English | MEDLINE | ID: mdl-28327958

ABSTRACT

BACKGROUND: Novel agents are changing the treatment of relapsed or refractory Hodgkin lymphoma (HL). Nevertheless, high-dose chemotherapy and autologous stem-cell transplantation (ASCT) are considered standard of care in eligible patients. To identify patients who could benefit most from novel therapeutic approaches, we investigated a comprehensive set of risk factors (RFs) for survival after ASCT. METHODS: In this multinational prognostic multivariable modeling study, 23 potential RFs were retrospectively evaluated in HL patients from nine prospective trials with multivariable Cox proportional hazards regression analyses (part I). The resulting prognostic score was then validated in an independent clinical sample (part II). RESULTS: In part I, we identified 656 patients treated for relapsed/refractory HL between 1993 and 2013 with a median follow-up of 60 months after ASCT. The majority of potential RFs had significant impact on progression-free survival (PFS) with hazard ratios (HR) ranging from 1.39 to 2.22. The multivariable analysis identified stage IV disease, time to relapse ≤3 months, ECOG performance status ≥1, bulk ≥5 cm and inadequate response to salvage chemotherapy [

Subject(s)
Hematopoietic Stem Cell Transplantation , Hodgkin Disease/therapy , Survival Analysis , Adult , Aged , Female , Humans , Male , Middle Aged , Prognosis , Proportional Hazards Models , Recurrence , Risk Factors
8.
BJOG ; 124(8): 1225-1233, 2017 Jul.
Article in English | MEDLINE | ID: mdl-27412153

ABSTRACT

OBJECTIVE: This study aimed to examine the factors associated with maternal mortality among women aged ≥35 years. DESIGN: Unmatched population based case-control study. SETTING: United Kingdom. POPULATION: Between 2009 and 2012, 105 cases of maternal deaths aged ≥35 years were extracted from the surveillance database of the MBRRACE-UK confidential enquiries into maternal deaths in the UK. In addition, 766 controls aged ≥35 years were identified from the UK Obstetric Surveillance System (2005-2012). METHODS: Risk factors known to be associated with maternal mortality and morbidity and for which data were available were examined for their association with maternal mortality among women ≥35 years using logistic regression analysis. MAIN OUTCOME MEASURES: Odds ratios and 95% confidence intervals associated with maternal death. RESULTS: Five factors were found to be significantly associated with increased odds of death among women aged ≥35 years: smoking during pregnancy (adjusted odds ratio (aOR) 2.06, 95% CI 1.13-3.75), inadequate use of antenatal care (aOR 23.62, 95% CI 8.79-63.45), medical co-morbidities (aOR 5.92, 95% CI 3.56-9.86) and previous pregnancy problems (aOR 2.06, 95% CI 1.23-3.45). The odds associated with death increased by 12% per year increase in age (aOR 1.12, 95% CI 1.02-1.22). CONCLUSION: Age was associated with maternal mortality even after adjusting for other known risk factors. Importantly, this study showed an association between maternal mortality and smoking among women aged 35 years or older. It emphasises the importance of public health action to reduce smoking levels and address trends in rising maternal age. TWEETABLE ABSTRACT: Smoking is a risk factor for maternal death for those aged over 35 years.


Subject(s)
Maternal Age , Maternal Death/etiology , Pregnancy Complications/etiology , Pregnancy Complications/mortality , Adult , Case-Control Studies , Female , Humans , Logistic Models , Maternal Mortality , Middle Aged , Odds Ratio , Pregnancy , Prenatal Care/statistics & numerical data , United Kingdom/epidemiology
9.
Acta Neurol Scand ; 135(5): 553-559, 2017 May.
Article in English | MEDLINE | ID: mdl-27397108

ABSTRACT

OBJECTIVES: To examine the usefulness of including sodium (Na) levels as a criterion to the SOAR stroke score in predicting inpatient and 7-day mortality in stroke. MATERIALS AND METHODS: Data from the Norfolk and Norwich University Hospital Stroke & TIA register (2003-2015) were analysed. Univariate and then multivariate models controlling for SOAR variables were used to assess the association between admission sodium levels and inpatient and 7-day mortality. The prognostic ability of the SOAR and SOAR Na scores for mortality outcomes at both time points were then compared using the Area Under the Curve (AUC) values from the Receiver Operating Characteristic curves. RESULTS: A total of 8493 cases were included (male=47.4%, mean (SD) 77.7 (11.6) years). Compared with normonatremia (135-145 mmol/L), hypernatraemia (>145 mmol/L) was associated with inpatient mortality and moderate (125-129 mmol/L) and severe hypontraemia (<125 mmol/L) with 7-day mortality after adjustment for stroke type, Oxfordshire Community Stroke Project classification, age, prestroke modified Rankin score and sex. The SOAR and SOAR-Na scores both performed well in predicting inpatient mortality with AUC values of .794 (.78-.81) and .796 (.78-.81), respectively. 7-day mortality showed similar results. Both scores were less predictive in those with chronic kidney disease (CKD) and more so in those with hypoglycaemia. CONCLUSION: The SOAR-Na did not perform considerably better than the SOAR stroke score. However, the performance of SOAR-Na in those with CKD and dysglycaemias requires further investigation.


Subject(s)
Severity of Illness Index , Sodium/blood , Stroke/blood , Stroke/diagnosis , Adult , Aged , Aged, 80 and over , Biomarkers/blood , Female , Hospital Mortality/trends , Hospitalization/trends , Humans , Male , Middle Aged , Predictive Value of Tests , Prognosis , Stroke/mortality
10.
Article in English | MEDLINE | ID: mdl-27865266

ABSTRACT

A randomized, blinded, negative controlled study was conducted to determine whether treatment with afoxolaner (NexGard®, Merial, Inc.) would prevent the transmission of Borrelia burgdorferi to dogs by wild caught Ixodes scapularis ticks. Twenty healthy dogs were randomly assigned to two groups of ten dogs each. Ten dogs were treated orally on Day 0 at a dose near the minimum recommended dose of afoxolaner of 2.5mg/kg (actual doses 2.5-3.1mg/kg) and ten control dogs were not treated. On Day 28, each dog was infested with approximately 50 adult unfed wild caught I. scapularis that had a 67% B. burgdorferi infection rate (determined by polymerase chain reaction). On Day 33, live ticks were counted and removed. No ticks were found on treated dogs while control dogs had an average of 21.4 ticks. To detect infection, the B. burgdorferi-specific C6 antibody SNAP® 4Dx® test (IDEXX) was performed on serum collected before infestation (all dogs seronegative on Days -6 and 27) and on Days 48, 63, 77 and 92. The ten treated dogs remained seronegative through the end of the study (Day 92), while nine out of the ten control dogs were infected, as demonstrated by their seroconversion to being positive for the presence of the B. burgdorferi-specific C6 antibody starting on Day 48. In this study, all dogs treated with NexGard® 28days prior to challenge with wild caught I. scapularis ticks were protected from B. burgdorferi infection, while nine out of the ten untreated control dogs were infected.


Subject(s)
Acaricides/administration & dosage , Dog Diseases/prevention & control , Isoxazoles/administration & dosage , Ixodes/microbiology , Lyme Disease/veterinary , Naphthalenes/administration & dosage , Tick Infestations/veterinary , Administration, Oral , Animals , Antibodies, Bacterial/blood , Borrelia burgdorferi/genetics , Borrelia burgdorferi/immunology , Borrelia burgdorferi/isolation & purification , Dog Diseases/microbiology , Dogs , Lyme Disease/microbiology , Lyme Disease/prevention & control , Lyme Disease/transmission , Tick Infestations/prevention & control
11.
Thromb Res ; 140 Suppl 1: S192, 2016 Apr.
Article in English | MEDLINE | ID: mdl-27161732

ABSTRACT

INTRODUCTION: Oncologists often receive phone calls from radiologists after regular working hours or while on call, informing them that a cancer patient has been diagnosed with a blood clot. In these situations, there may not be nursing staff available to contact the patient and provide teaching for Low Molecular Weight Heparin (LMWH) injections. As a result, patients are often sent to the emergency for injection and teaching, taxing an already overburdened emergency department. This problem constitutes an important care gap. AIM: In Alberta, Canada, pharmacists are able to prescribe medications including LMWH. We designed an after-hours program to provide care for cancer patients diagnosed with VTE. MATERIALS AND METHODS: Once the oncologist is made aware of the patient with a clot, a simple one page document is filled out and faxed to a 24-hour outpatient pharmacy outlining the following: patient demographics, clot location, systemic therapy, current anticoagulant and anti-platelet agents. The oncologist has the option to specify desired LMWH. The patient goes to the pharmacy where the pharmacist weighs the patient, reviews blood work electronically and prescribes the LMWH. Also provided are injection teaching and telephone follow-up. A specific algorithm is followed with the pharmacist able to contact the on call oncologist in specific situations where the patient's condition falls outside of the algorithm guideline. The pharmacist is able to order blood work, particularly to evaluate for Heparin Induced Thrombocytopenia. Patients must follow up with their oncologist within 7 days of diagnosis. RESULTS: This program has been run as a pilot and preliminary data will be presented at the ICTHIC meeting. Specifically, we will assess usage of the program, appropriateness of therapy chosen according to Canadian practice guidelines, as well as patient, pharmacist and physician satisfaction with the program. CONCLUSIONS: We believe that this outpatient pharmacy program is innovative, will decrease burden on emergency departments, and takes advantage of our pharmacists' ability to independently assess patients and write prescriptions. This program may serve as a model for other cancer centers looking for a novel way to provide after-hours care of patients diagnosed with VTE.

12.
Vet Parasitol ; 206(1-2): 5-13, 2014 Nov 15.
Article in English | MEDLINE | ID: mdl-25458121

ABSTRACT

Tetracycline treatment of animals or humans infected with filariae that harbor Wolbachia endosymbionts blocks further embryogenesis, and existing microfilariae gradually die. This treatment also kills developing larvae and has a slow-kill effect on adult filariae, all presumably due to elimination of the Wolbachia. Also, Dirofilaria immitis microfilariae in blood collected from dogs up to 25 days after the last dose of doxycycline developed to infective L3 that were normal in appearance and motility in mosquitoes but did not continue to develop or migrate normally after subcutaneous (SC) injection into dogs. The present study was designed to determine whether heartworm microfilariae collected at later times after treatment would regain the ability to continue normal development in a dog. The study also was expected to yield valuable data on the effects of treatment on microfilariae and antigen levels and adult worms. The study was conducted in 16 dogs as two separate replicates at different times. A total of five dogs (two in Replicate A and three in Replicate B) infected either by SC injection of L3 or intravenous transplantation of adult heartworms were given doxycycline orally at 10mg/kg twice daily for 30 days, with three untreated controls. Microfilarial counts in the five treated dogs gradually declined during the 12-13 months after treatment initiation. Two dogs were amicrofilaremic before necropsy and three had 13 or fewer microfilariae/ml. Only one treated dog was negative for heartworm antigen before necropsy. Overall, treated dogs generally had fewer live adult heartworms than controls, and most of their live worms were moribund. All three control dogs remained positive for microfilariae and antigen and had many live worms. L3 from mosquitoes fed on blood collected 73-77 or 161-164 days after initiation of doxycycline treatments were injected SC into five dogs. None of the dogs injected with L3 from mosquitoes fed on blood from doxycycline-treated dogs were ever positive for microfilariae or antigen, and none had worms at necropsy; three control dogs were positive for microfilariae and antigen and had many live worms. These data indicate that doxycycline treatment of microfilaremic dogs gradually reduces numbers of microfilariae and blocks further transmission of heartworms. This latter effect should be highly effective in reducing the rate of selection of heartworms with genes that confer resistance to macrocyclic lactone preventives and microfilaricides. The data also suggest that doxycycline has a slow-kill effect on adult heartworms.


Subject(s)
Dirofilaria immitis/drug effects , Dirofilariasis/drug therapy , Dog Diseases/drug therapy , Doxycycline/pharmacology , Doxycycline/therapeutic use , Animals , Antigens, Helminth/blood , Culicidae/parasitology , Dirofilaria immitis/embryology , Dirofilariasis/transmission , Dog Diseases/transmission , Dogs , Embryonic Development/drug effects , Microfilariae/drug effects
13.
Vet Parasitol ; 206(1-2): 93-8, 2014 Nov 15.
Article in English | MEDLINE | ID: mdl-25218886

ABSTRACT

To better understand the efficacy of doxycycline and 10% imidacloprid+2.5% moxidectin (Advantage Multi(®); Bayer Animal Health, Shawnee Mission, Kansas) on immature adult Dirofilaria immitis parasites and the results of antigen tests, 12 healthy, randomly selected dogs were experimentally infected with D. immitis and monitored for 407 days. Two dogs in each of three subgroups of four dogs were each infected with six (total of 6 dogs) or 12 (total of 6 dogs) D. immitis infective third-stage larvae (L3) obtained from infected mosquitoes. Doxycycline (10mg/kg per os twice daily×30 days) and 10% imidacloprid+2.5% moxidectin (1ml/kg by topical application every 30 days) treatment was initiated at 105 (Group A) and 149 (Group B) days post infection (PI) in two groups. One subgroup of two dogs given 6 L3 and one subgroup of two dogs given 12 L3 remained as untreated controls (GroupC). Serum obtained regularly throughout the study was evaluated by ELISA (PetChek(®) Heartworm-PF Antigen Test, IDEXX Laboratories, Inc.) for D. immitis adult circulating antigens. Six of the eight dogs in the treated groups had detectable antigenemia starting between 148 and 240 days post infection, but antigen was not detected in any treated dog at the end of the study. In the control subgroups, the dogs that received 6 L3 had no detectable antigen while the two dogs that received 12 L3 had detectable antigen beginning on Day 180 that persisted until the end of the study. None of the infected dogs had evidence of circulating microfilariae. At necropsy, no heartworms were recovered from the treated dogs, but all dogs in the untreated group had viable adult heartworms. These results indicate that early immature adult worms (3.5 and 5 months of age) of D. immitis were susceptible to a combined treatment regimen of doxycycline and 10% imidacloprid+2.5% moxidectin.


Subject(s)
Dirofilaria immitis/drug effects , Dirofilariasis/drug therapy , Dog Diseases/drug therapy , Filaricides/pharmacology , Filaricides/therapeutic use , Animals , Antigens, Helminth/blood , Dirofilariasis/diagnosis , Dog Diseases/diagnosis , Dogs , Doxycycline/pharmacology , Doxycycline/therapeutic use , Drug Therapy, Combination/veterinary , Female , Imidazoles/pharmacology , Imidazoles/therapeutic use , Macrolides/pharmacology , Macrolides/therapeutic use , Male , Neonicotinoids , Nitro Compounds/pharmacology , Nitro Compounds/therapeutic use , Random Allocation
14.
Sci Total Environ ; 434: 201-12, 2012 Sep 15.
Article in English | MEDLINE | ID: mdl-22035560

ABSTRACT

Soluble reactive phosphorus (SRP) concentrations in the River Thames, south east England, have significantly decreased from an annual maximum of 2100 µg l(-1) in 1997 to 344 in 2010, primarily due to the introduction of phosphorus (P) removal at sewage treatment works within the catchment. However, despite this improvement in water quality, phytoplankton biomass in the River Thames has greatly increased in recent years, with peak chlorophyll concentrations increasing from 87 µg l(-1) in the period 1997 to 2002, to 328 µg l(-1) in 2009. A series of within-river flume mesocosm experiments were performed to determine the effect of changing nutrient concentrations and light levels on periphyton biomass accrual. Nutrient enrichment experiments showed that phosphorus, nitrogen and silicon were not limiting or co-limiting periphyton growth in the Thames at the time of the experiment (August-September 2010). Decreasing ambient SRP concentration from 225 µg l(-1) to 173 µg l(-1) had no effect on periphyton biomass accrual rate or diatom assemblage. Phosphorus limitation became apparent at 83 µg SRP l(-1), at which point a 25% reduction in periphyton biomass was observed. Diatom assemblage significantly changed when the SRP concentration was reduced to 30 µg l(-1). Such stringent phosphorus targets are costly and difficult to achieve for the River Thames, due to the high population density and intensive agriculture within the Thames basin. Reducing light levels by shading reduced the periphyton accrual rate by 50%. Providing shading along the River Thames by planting riparian tree cover could be an effective measure to reduce the risk of excessive algal growth. If the ecology of the Thames is to reach the WFD's "good ecological status", then both SRP concentration reductions (probably to below 100 µg l(-1)) and increased shading will be required.


Subject(s)
Light , Biomass , England , Phosphorus/analysis , Sewage , Water/chemistry
15.
Vet Parasitol ; 176(4): 357-60, 2011 Mar 22.
Article in English | MEDLINE | ID: mdl-21292403

ABSTRACT

Adulticide therapy in heartworm (Dirofilaria immitis)-infected dogs can lead to thromboembolism, which can seriously compromise post-treatment health status. Lung pathology following adulticide therapy was evaluated in three groups of experimentally infected dogs. Group 1 was treated with doxycycline at 20 mg/kg per os once daily for 30 days post infection followed by an intramuscular injection of melarsomine dihydrochloride (2.5 mg/kg) at Week 12, followed 1 month later by two injections 24 h apart. Group 2 was treated as described for Group 1, with the addition of ivermectin at 6 mcg/kg given monthly per os for 24 weeks post-infection. Group 3 received melarsomine alone, as described above. All dogs were necropsied at Week 24 and lung pathology was evaluated. Lesion criteria included perivascular inflammation and endothelial proliferation. Lesions were scored by two independent pathologists who were blinded as to treatment. Results indicate that doxycycline treatment alone or combined with ivermectin had lower lesion scores than lungs from dogs who had received melarsomine alone. Dogs that received the combined doxycycline/ivermectin protocol and treated with adulticide showed less severe arterial lesions and the virtual absence of thrombi.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Antiparasitic Agents/therapeutic use , Dirofilariasis/drug therapy , Dog Diseases/drug therapy , Lung/pathology , Administration, Oral , Animals , Anti-Bacterial Agents/administration & dosage , Antiparasitic Agents/administration & dosage , Arsenicals/administration & dosage , Arsenicals/therapeutic use , Dirofilaria immitis/drug effects , Dirofilaria immitis/pathogenicity , Dirofilariasis/pathology , Dog Diseases/parasitology , Dog Diseases/pathology , Dogs , Doxycycline/administration & dosage , Doxycycline/therapeutic use , Drug Therapy, Combination/veterinary , Female , Injections, Intramuscular/veterinary , Ivermectin/administration & dosage , Ivermectin/therapeutic use , Male , Time Factors , Triazines/administration & dosage , Triazines/therapeutic use , Wolbachia/drug effects , Wolbachia/pathogenicity
16.
Vet Parasitol ; 176(4): 361-7, 2011 Mar 22.
Article in English | MEDLINE | ID: mdl-21345592

ABSTRACT

The antifilarial effects of tetracycline drugs were first demonstrated when they were found to be highly effective against L(3) and L(4) of Brugia pahangi and Litomosoides sigmodontis in rodent models. Tetracyclines are also now known to have activity against microfilariae and adult Dirofilaria immitis, but assessment of their activity against larval and juvenile heartworms has not been reported previously. This study assessed the effects of doxycycline administered orally at 10mg/kg twice daily for 30-day periods at selected times during the early part of the life cycle of D. immitis in dogs with dual infections of D. immitis and B. pahangi. Twenty beagles were randomly allocated by weight to four groups of five dogs each. On Day 0, each dog was given 50 D. immitis L(3) and 200 B. pahangi L(3) by SC injection. Dogs received doxycycline on Days 0-29 (Group 1); Days 40-69 (Group 2); or Days 65-94 (Group 3). Group 4 served as untreated controls. Blood samples were collected for microfilariae counting and antigen testing. Necropsy for collection of adult heartworms and selected tissues were performed Days 218-222. Heartworms recovered were examined by immunohistology, conventional microscopy/transmission electron microscopy, and molecular biology techniques. No live heartworms were recovered from dogs in Group 1; dogs in Group 2 had 0 to 2 live worms (98.4% efficacy), and dogs in Group 3 had 0-36 live worms (69.6% efficacy). All control dogs had live adult heartworms (25-41). The live worms recovered from dogs in Groups 2 and 3 were less developed and smaller that worms from control dogs. Microfilariae were not detected in any dogs in Groups 1 and 2; one dog in Group 3 had 1 microfilariae/ml at necropsy. All control dogs had microfilariae at necropsy. One dog in Group 1 was antigen positive at one sampling (Day 166). One dog in Group 2 was antigen positive Days 196 and 218-222 and three dogs in Group 3 were antigen positive at one or more samplings All five control dogs were antigen positive at all three sampling times. These findings suggest that doxycycline at 10mg/kg orally twice daily for 30 days has efficacy against migrating tissue-phase larvae and juvenile worms and will delay or restrict microfilarial production.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Brugia pahangi/drug effects , Dirofilariasis/drug therapy , Dog Diseases/drug therapy , Doxycycline/therapeutic use , Filariasis/veterinary , Administration, Oral , Animals , Anti-Bacterial Agents/administration & dosage , Anti-Bacterial Agents/pharmacology , Antigens, Helminth/blood , Brugia pahangi/pathogenicity , Dirofilaria immitis/drug effects , Dirofilaria immitis/pathogenicity , Dirofilariasis/complications , Dirofilariasis/parasitology , Dog Diseases/parasitology , Dogs , Doxycycline/administration & dosage , Doxycycline/pharmacology , Female , Filariasis/complications , Filariasis/drug therapy , Larva/drug effects , Larva/pathogenicity , Male , Microfilariae/drug effects , Microfilariae/pathogenicity , Random Allocation , Time Factors
17.
Vet Parasitol ; 158(3): 204-14, 2008 Dec 10.
Article in English | MEDLINE | ID: mdl-18930598

ABSTRACT

A safer, more effective adulticidal treatment and a safe method for reducing microfilaremia and breaking transmission of heartworm disease early in the treatment are needed. The present study evaluated efficacy of ivermectin (IVM) and doxycycline (DOXY) alone or together (with or without melarsomine [MEL]) in dogs with induced adult heartworm infection and assessed the ability of microfilariae from DOXY-treated dogs to develop to L3 in Aedes aegypti mosquitoes and subsequently to become reproductive adults in dogs. Thirty beagles were each infected with 16 adult heartworms by intravenous transplantation. Six weeks later, dogs were ranked by microfilarial count and randomly allocated to 6 groups of 5 dogs each. Beginning on Day 0, Group 1 received IVM (6 mcg/kg) weekly for 36 weeks. Group 2 received DOXY (10 mcg/(kgday)) orally Weeks 1-6, 10-11, 16-17, 22-25, and 28-33. Groups 3 and 5 received IVM and DOXY according to doses and schedules used for Groups 1 and 2. At Week 24, Groups 3 and 4 received an intramuscular injection of MEL (2.5 mg/kg), followed 1 month later by two injections 24h apart. Group 6 was not treated. Blood samples were collected for periodic microfilaria counts and antigen (Ag) testing (and later immunologic evaluation and molecular biology procedures). Radiographic and physical examinations, hematology/clinical chemistry testing, and urinalysis were done before infection, before Day 0, and periodically during the treatment period. At 36 weeks, the dogs were euthanized and necropsied for worm recovery, collection of lung, liver, kidney, and spleen samples for examination by immunohistochemistry and conventional histological methods. All dogs treated with IVM + DOXY (with or without MEL) were amicrofilaremic after Week 9. Microfilarial counts gradually decreased in dogs treated with IVM or DOXY, but most had a few microfilariae at necropsy. Microfilarial counts for dogs treated only with MEL were similar to those for controls. Antigen test scores gradually decreased with IVM + DOXY (with or without MEL) and after MEL. Antigen scores for IVM or DOXY alone were similar to controls throughout the study. Reduction of adult worms was 20.3% for IVM, 8.7% for DOXY, 92.8% for IVM + DOXY + MEL, 100% for MEL, and 78.3% for IVM + DOXY. Mosquitoes that fed on blood from DOXY-treated dogs had L3 normal in appearance but were not infective for dogs. Preliminary observations suggest that administration of DOXY+IVM for several months prior to (or without) MEL will eliminate adult HW with less potential for severe thromboembolism than MEL alone.


Subject(s)
Arsenicals/therapeutic use , Dirofilaria immitis/microbiology , Dirofilariasis/drug therapy , Doxycycline/therapeutic use , Filaricides/therapeutic use , Ivermectin/therapeutic use , Triazines/therapeutic use , Aedes/microbiology , Animals , Anti-Bacterial Agents/adverse effects , Anti-Bacterial Agents/therapeutic use , Antiparasitic Agents/adverse effects , Antiparasitic Agents/therapeutic use , Arsenicals/adverse effects , Dirofilaria immitis/drug effects , Dog Diseases/drug therapy , Dogs , Dose-Response Relationship, Drug , Doxycycline/adverse effects , Female , Filaricides/adverse effects , Ivermectin/adverse effects , Male , Microfilariae , Random Allocation , Thromboembolism/chemically induced , Thromboembolism/prevention & control , Thromboembolism/veterinary , Time Factors , Treatment Outcome , Triazines/adverse effects , Wolbachia/drug effects
18.
Hum Vaccin ; 4(5): 389-92, 2008.
Article in English | MEDLINE | ID: mdl-18437056

ABSTRACT

The presence of circulating tumor cells (CTC) from various cancers has provided a wealth of information and possibilities. As the role of CTC detection in the treatment assessment of metastatic breast cancer becomes standard, there is interest in applying this tool in cancer vaccine development and clinical trial monitoring. Since we lack a proven immunologic assay that correlates with clinical response, CTC detection, quantification and phenotypic characterization may be a useful surrogate for clinical outcome. The Cancer Vaccine Development Program is involved in the development of HER2/neu peptide based vaccine development for the prevention of recurrence in HER2/neu expressing cancers like breast cancer. The CellSearch System (Veridex, LLC Warren, NJ) has been used by our lab in conjunction with in vivo and/or in vitro immunologic measurements to define a monitoring tool that could predict clinical response. Once validated, this assay could significantly shorten clinical trials and lead to more efficient assessment of potentially promising cancer vaccines.


Subject(s)
Blood Cells , Breast Neoplasms/diagnosis , Breast Neoplasms/immunology , Cancer Vaccines/immunology , Biomarkers , Cell Count , Humans , Treatment Outcome
20.
Proc Natl Acad Sci U S A ; 103(46): 17179-83, 2006 Nov 14.
Article in English | MEDLINE | ID: mdl-17088554

ABSTRACT

Plutonium possesses the most complicated phase diagram in the periodic table, driven by the complexities of overlapping 5f electron orbitals. Despite the importance of the 5f electrons in defining the structure and physical properties, there is no experimental evidence that these electrons localize to form magnetic moments in pure Pu. Instead, a large temperature-independent Pauli susceptibility indicates that they form narrow conduction bands. Radiation damage from the alpha-particle decay of Pu creates numerous defects in the crystal structure, which produce a significant temperature-dependent magnetic susceptibility, chi(T), in both alpha-Pu and delta-Pu (stabilized by 4.3 atomic percent Ga). This effect can be removed by thermal annealing above room temperature. By contrast, below 35 K the radiation damage is frozen in place, permitting the evolution in chi(T) with increasing damage to be studied systematically. This result leads to a two-component model consisting of a Curie-Weiss term and a short-ranged interaction term consistent with disorder-induced local moment models. Thus, it is shown that self-damage creates localized magnetic moments in previously nonmagnetic plutonium.

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