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1.
J Mol Med (Berl) ; 2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38940937

ABSTRACT

The rapidly aging population is consuming more alcohol, leading to increased alcohol-associated acute pancreatitis (AAP) with high mortality. However, the mechanisms remain undefined, and currently there are no effective therapies available. This study aims to elucidate aging- and alcohol-associated spatial transcriptomic signature by establishing an aging AAP mouse model and applying Visium spatial transcriptomics for understanding of the mechanisms in the context of the pancreatic tissue. Upon alcohol diet feeding and caerulein treatment, aging mice (18 months) developed significantly more severe AAP with 5.0-fold increase of injury score and 2.4-fold increase of amylase compared to young mice (3 months). Via Visium spatial transcriptomics, eight distinct tissue clusters were revealed from aggregated transcriptomes of aging and young AAP mice: five acinar, two stromal, and one islet, which were then merged into three clusters: acinar, stromal, and islet for the comparative analysis. Compared to young AAP mice, > 1300 differentially expressed genes (DEGs) and approximately 3000 differentially regulated pathways were identified in aging AAP mice. The top five DEGs upregulated in aging AAP mice include Mmp8, Ppbp, Serpina3m, Cxcl13, and Hamp with heterogeneous distributions among the clusters. Taken together, this study demonstrates spatial heterogeneity of inflammatory processes in aging AAP mice, offering novel insights into the mechanisms and potential drivers for AAP development. KEY MESSAGES: Mechanisms regarding high mortality of AAP in aging remain undefined. An aging AAP mouse model was developed recapturing clinical exhibition in humans. Spatial transcriptomics identified contrasted DEGs in aging vs. young AAP mice. Top five DEGs were Mmp8, Ppbp, Serpina3m, Cxcl13, and Hamp in aging vs. young AAP mice. Our findings shed insights for identification of molecular drivers in aging AAP.

2.
Plants (Basel) ; 11(21)2022 Oct 26.
Article in English | MEDLINE | ID: mdl-36365297

ABSTRACT

Enterolobium cyclocarpum and Piscidia piscipula are two important tree Fabaceae species distributed from the Yucatan Peninsula, Mexico. Our aims were focused on the E. cyclocarpum and P. piscipula seeds for: (1) to examine the seed permeability and imbibition rate, (2) to evaluate the effect of seed pre-germinative treatments, and (3) to characterize the structures involved on the presence of physical dormancy (PY). We used fresh seeds to determine seed permeability and imbibition rate, seed viability by means of tetrazolium test, furthermore, we applied mechanical scarification and boiler shocks for 5 s, 10 s and 15 s treatments. Morphological characterization of the seed coat was by Scanning Electron Microscope (SEM). Seed viability in E. cyclocarpum and P. piscipula were 100% and 96%, respectively. Seed permeability and imbibition rate in E. cyclocarpum were low. The highest germination in E. cyclocarpum was in the mechanical scarification (92%), while in P. piscipula, this parameter was in the 10 s boiling water treatment (76.0%). The presence of PY was confirmed in both species because they showed low seed permeability, and imbibition rate; furthermore, exhibited macrosclereids cells. The present research seeks to promote the sustainable use of E. cyclocarpum and P. piscipula.

3.
Comp Med ; 72(4): 243-247, 2022 08 01.
Article in English | MEDLINE | ID: mdl-35803708

ABSTRACT

This report describes an anesthesia technique that we used to study cardiovascular anatomy and physiology with echocardiography and cardiac magnetic resonance (CMR) in 46 African clawed frogs (Xenopus laevis) (n = 24 for electrocardiography and n = 22 for CMR). For administration of anesthesia, 3 holding tanks, one each for transportation, sedation, and recovery, were filled with filtered water, with 0.05% buffered tricaine methasulfonate solution (MS-222) added into the sedation tank. Fifteen minutes after the frog was placed in the sedation tank, a paper towel was soaked in MS-222 solution, and the frog was placed in a supine position and rolled 3 to 4 times in the soaked paper with the head and legs exposed. Vital signs were monitored and recorded throughout the procedure. After imagining, frogs were unrolled from the paper towel, placed in the recovery tank, and later returned to their home tank. Monitoring was discontinued when the frogs resumed typical activity. No mortality or complications were observed in frogs that underwent this procedure. Mean duration ±1 SD of anesthesia induction was 12 ± 5 min in the echocardiography group and 14 ± 6 min in the CMR group. The mean duration of anesthesia maintenance was 60 ± 18 min in the echocardiography group and 118 ± 37 min in the CMR group. An additional dose of anesthesia was necessary during maintenance for 9 of 24 (37%) frogs in the echocardiography group and 6 of 22 (27%) frogs in the CMR group. At the end of the procedure, the mean oxygen saturation was 66 ± 9% in the echocardiography group and 85 ± 6% in the CMR group, and heart rate was 48 ± 13 beats/min in the echocardiography group and 42 ± 7 beats/min in the CMR group. We conclude that the anesthesia technique of immersion in MS-222 is suitable for performing echocardiography and CMR imaging in this species without complications.


Subject(s)
Anesthesia, General , Magnetic Resonance Imaging , Animals , Echocardiography , Heart Rate , Xenopus laevis
4.
Cell Biosci ; 11(1): 28, 2021 Feb 02.
Article in English | MEDLINE | ID: mdl-33531047

ABSTRACT

BACKGROUND: A systemic evaluation of immune cell infiltration patterns in experimental acute pancreatitis (AP) is lacking. Using multi-dimensional flow cytometry, this study profiled infiltrating immune cell types in multiple AP mouse models. METHODS: Three AP models were generated in C57BL/6 mice via cerulein (CAE) injection, alcohol and palmitoleic acid (EtOH + POA) injection, and alcohol diet feeding and cerulein (EtOH + CAE) injection. Primary pancreatic cells and splenocytes were prepared, and multi-dimensional flow cytometry was performed and analyzed by manual gating and computerized PhenoGraph, followed by visualization with t-distributed stochastic neighbor embedding (t-SNE). RESULTS: CAE treatment induced a time-dependent increase of major innate immune cells and a decrease of follicular B cells, and TCD4+ cells and the subtypes in the pancreas, whereas elicited a reversed pattern in the spleen. EtOH + POA treatment resulted in weaker effects than CAE treatment. EtOH feeding enhanced CAE-induced amylase secretion, but unexpectedly attenuated CAE-induced immune cell regulation. In comparison with manual gating analysis, computerized analysis demonstrated a remarkable time efficiency and reproducibility on the innate immune cells and B cells. CONCLUSIONS: The reverse pattern of increased innate and decreased adaptive immune cells was consistent in the pancreas in CAE and EtOH + POA treatments. Alcohol feeding opposed the CAE effect on immune cell regulation. Together, the immune profiling approach utilized in this study provides a better understanding of overall immune responses in AP, which may facilitate the identification of intervention windows and new therapeutic strategies. Computerized analysis is superior to manual gating by dramatically reducing analysis time.

5.
Behav Pharmacol ; 31(5): 458-464, 2020 08.
Article in English | MEDLINE | ID: mdl-31770113

ABSTRACT

During daily 3-h sessions, four rhesus monkeys had concurrent access to 16% alcohol (w/v) and saccharin. A response occurred when a monkey made mouth contact with the metal spout and thereby completed a drinkometer circuit. The liquids were available under concurrent nonindependent fixed-ratio 32 schedules. With these schedules, responses on the right spout decremented both the right and left fixed-ratio counters and vice versa. Responding was well maintained by both alcohol and saccharin. Increases in saccharin concentration produced increases in saccharin responding to the point that saccharin responding exceeded alcohol responding. Responses per saccharin delivery were also a direct function of the saccharin concentration. In contrast, responses per alcohol delivery generally decreased as the saccharin concentration became greater. Changeover or switching responses were also a direct function of the saccharin concentration. Relative reinforcing effects of each combination of liquid pairs were measured for each monkey. For all monkeys, it was possible to establish equal rates of responding for both reinforcers and frequent switching between reinforcers. The balanced responding can serve as a baseline for the evaluation of potential treatments that may alter relative reinforcing effects.


Subject(s)
Conditioning, Operant/drug effects , Ethanol/pharmacology , Saccharin/pharmacology , Animals , Dose-Response Relationship, Drug , Macaca mulatta , Male , Reinforcement Schedule , Self Administration
6.
Emerg Infect Dis ; 25(5): 1011-1014, 2019 05.
Article in English | MEDLINE | ID: mdl-30741630

ABSTRACT

In the United States, outbreaks of avian influenza H5 and H7 virus infections in poultry have raised concern about the risk for infections in humans. We reviewed the data collected during 2014-2017 and found no human infections among 4,555 exposed responders who were wearing protection.


Subject(s)
Influenza A virus , Influenza in Birds/epidemiology , Influenza in Birds/virology , Poultry Diseases/epidemiology , Poultry Diseases/virology , Animals , Disease Outbreaks , History, 21st Century , Influenza A virus/classification , Influenza in Birds/history , Poultry , Poultry Diseases/history , Public Health Surveillance , United States/epidemiology
7.
J Am Assoc Lab Anim Sci ; 57(1): 44-50, 2018 01 01.
Article in English | MEDLINE | ID: mdl-29402351

ABSTRACT

Despite few published studies that assess the accuracy of glucometers in laboratory animals, glucometers are commonly used in animal research. We set out to determine the accuracy of 5 point-of-care glucometers (POCG) when used to evaluate murine whole blood, plasma, and serum samples. The POCG tested included one veterinary device (POCG A) and 4 humanuse instruments (POCG B through E). Whole blood, plasma, and serum samples from 50 female C57BL/6J mice were analyzed on all POCG, and serum was analyzed on a reference biochemical analyzer. The mean blood glucose concentration (BGC) measured in whole blood by using POCG A was greater than that on the biochemical analyzer, whereas the mean BGC in whole blood according to POCG B through E did not differ significantly from that on the biochemical analyzer. Mean BGC in plasma and serum did not differ between POCG B and E and the biochemical analyzer, whereas the plasma and serum BGC values from POCG C and D were greater than the mean BGC from the biochemical analyzer. The accuracy of each POCG for each sample type was evaluated by analyzing mean differences, correlations, and Bland-Altman graphs. We found that the 4 human-use POCG are appropriate for use with whole blood from female C57BL/6J mice, whereas only 2 of the evaluated POCG were sufficiently accurate for use with plasma or serum.


Subject(s)
Blood Chemical Analysis/veterinary , Blood Glucose/chemistry , Point-of-Care Systems , Animals , Blood Chemical Analysis/instrumentation , Female , Laboratory Animal Science , Mice , Mice, Inbred C57BL , Sensitivity and Specificity
8.
Phys Rev E ; 95(6-1): 063113, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28709211

ABSTRACT

The present interdisciplinary study combines electromagnetics and combustion to unveil an original and basic experiment displaying a spontaneous flame instability that is mitigated as the non-premixed sooting flame experiences a magnetic perturbation. This magnetic instability mitigation is reproduced by direct numerical simulations to be further elucidated by a flow stability analysis. A key role in the stabilization process is attributed to the momentum and thermochemistry coupling that the magnetic force, acting mainly on paramagnetic oxygen, contributes to sustain. The spatial local stability analysis based on the numerical simulations shows that the magnetic field tends to reduce the growth rates of small flame perturbations.

9.
J Exp Med ; 214(1): 107-123, 2017 01.
Article in English | MEDLINE | ID: mdl-27994068

ABSTRACT

Regulatory T (T reg) cell deficiency causes lethal, CD4+ T cell-driven autoimmune diseases. Stem cell transplantation is used to treat these diseases, but this procedure is limited by the availability of a suitable donor. The intestinal microbiota drives host immune homeostasis by regulating the differentiation and expansion of T reg, Th1, and Th2 cells. It is currently unclear if T reg cell deficiency-mediated autoimmune disorders can be treated by targeting the enteric microbiota. Here, we demonstrate that Foxp3+ T reg cell deficiency results in gut microbial dysbiosis and autoimmunity over the lifespan of scurfy (SF) mouse. Remodeling microbiota with Lactobacillus reuteri prolonged survival and reduced multiorgan inflammation in SF mice. L. reuteri changed the metabolomic profile disrupted by T reg cell deficiency, and a major effect was to restore levels of the purine metabolite inosine. Feeding inosine itself prolonged life and inhibited multiorgan inflammation by reducing Th1/Th2 cells and their associated cytokines. Mechanistically, the inhibition of inosine on the differentiation of Th1 and Th2 cells in vitro depended on adenosine A2A receptors, which were also required for the efficacy of inosine and of L. reuteri in vivo. These results reveal that the microbiota-inosine-A2A receptor axis might represent a potential avenue for combatting autoimmune diseases mediated by T reg cell dysfunction.


Subject(s)
Autoimmunity , Gastrointestinal Microbiome , Limosilactobacillus reuteri , Receptor, Adenosine A2A/physiology , T-Lymphocytes, Regulatory/immunology , Animals , Cell Differentiation , Female , Inosine/pharmacology , Male , Metabolomics , Mice , Mice, Inbred C57BL , Th1 Cells/cytology , Th2 Cells/cytology
10.
J Exp Anal Behav ; 106(1): 75-92, 2016 07.
Article in English | MEDLINE | ID: mdl-27402525

ABSTRACT

Choice behavior was studied under concurrent nonindependent fixed-ratio fixed-ratio (nFR) schedules of reinforcement, as these schedules result in frequent changeover responses. With these schedules, responses on either operandum count toward the completion of the ratio requirements of both schedules. Five monkeys were subjects, and two pairs of liquid reinforcers were concurrently available: 16% (w/v) and 0% ethanol or 16% and 8% ethanol. For each pair of reinforcers, the nFR sizes were systematically altered across sessions while keeping the schedule size equal for both liquids. Responding varied as a function of reinforcer pair and nFR size. With the 16% and 0% pair, higher response rates were maintained by 16% and were an inverted U-shape function of nFR size. With 16% and 8%, a greater number of responses initially occurred on the schedule that delivered 8% ethanol. However, as nFR size increased, preference reversed such that responses that delivered 16% ethanol were greater. When the nFR size was subsequently decreased, preference reverted back to 8%. Number of responses emitted per delivery was a dependent variable and, in behavioral economic terms, was the price paid for each liquid delivery. With 16% and 0%, changeover responses initially increased and then decreased as schedule size became larger. In contrast, with the 16% and 8% pair, changeover responses increased directly with schedule size. Responding under nFR schedules is sensitive to differences in reinforcer magnitude and demonstrates that relative reinforcing effects can change as a function of schedule size.


Subject(s)
Central Nervous System Depressants/administration & dosage , Ethanol/administration & dosage , Reinforcement Schedule , Self Administration , Animals , Choice Behavior , Macaca mulatta
11.
J Am Assoc Lab Anim Sci ; 55(3): 291-4, 2016.
Article in English | MEDLINE | ID: mdl-27177561

ABSTRACT

Zebrafish (Danio rerio) are a popular vertebrate model in biomedical research, but information describing the effects of environmental enrichment on fertility and fecundity of zebrafish is sparse. In the current study, 18 breeding pairs were placed in divided 1.5-L breeding tanks containing 1 of 3 enrichment conditions: plastic grass (n = 6), plastic leaves (n = 6), or no enrichment (n = 6, control). The pairs were allowed to spawn for 3 h the next day, after which eggs were counted and breeding pairs were returned to holding tanks for use in subsequent sessions. Spawning sessions were repeated at 7-d intervals until the completion of 9 trials, with pairs rotating to a different condition at each interval. Total egg count (mean ± SEM) after 3 h was greater for zebrafish spawning in the grass environment (48.0 ± 7.7 eggs) than in the leaf or control environments (29.4 ± 5.3 and 20.4 ± 3.7 eggs, respectively). An interaction emerged between enrichment type and the age of the spawning pair on the number of fry at 6 d postfertilization (dpf). Initially, more fry were obtained from 110- and 160-dpf pairs with the grass enrichment, but from 173- and 180-dpf pairs there were more obtained with leaf enrichment than grass. A separate experiment showed that enrichment type did not have an effect on fry survivability. Overall, our data indicates that, under certain conditions, zebrafish fertility and fecundity are greater in a breeding tank containing environmental enrichment than in a bare tank.


Subject(s)
Fertility , Housing, Animal , Zebrafish/physiology , Animals , Breeding , Female , Male
12.
One Health ; 2: 144-149, 2016 Dec.
Article in English | MEDLINE | ID: mdl-28616489

ABSTRACT

Live poultry-associated salmonellosis is an emerging public health issue in the United States. Public and animal health officials collaborated to investigate one of the largest (356 cases, 39 states) of these outbreaks reported to date. A case was defined as illness in a person infected with the outbreak strain of Salmonella Typhimurium with illness onset between 1 March and 22 October 2013. The median patient age was seven years (range: < 1-87 years); 58% of ill persons were children ≤ 10 years, 51% were female, 25% were hospitalized; 189 (76%) of 250 patients reported live poultry exposure in the week before illness; and 149 (95%) of 157 reported purchasing live poultry from agricultural feed stores. Traceback investigations identified 18 live poultry sources, including 16 mail-order hatcheries. Environmental sampling was conducted at two mail-order hatcheries. One (2.5%) of 40 duplicate samples collected at one hatchery yielded the outbreak strain. Live poultry are an important source of human salmonellosis, particularly among children, highlighting the need for educational campaigns and comprehensive interventions at the mail-order hatchery and agricultural feed store levels. Prevention and control efforts depend on a One Health approach, involving cooperation between public and animal health officials, industry, health professionals, and consumers.

13.
MMWR Morb Mortal Wkly Rep ; 64(9): 258, 2015 Mar 13.
Article in English | MEDLINE | ID: mdl-25763879

ABSTRACT

In early 2014, five clusters of human Salmonella infections were identified through PulseNet, the national molecular subtyping network for foodborne disease surveillance. Many ill persons in each of these clusters reported contact with live poultry, primarily chicks and ducklings, from a single mail-order hatchery; therefore, the clusters were merged into a single investigation. During February 3-October 14, 2014, a total of 363 persons infected with outbreak strains of Salmonella serotypes Infantis, Newport, and Hadar were reported from 43 states and Puerto Rico, making it the largest live poultry-associated salmonellosis outbreak reported in the United States.


Subject(s)
Disease Outbreaks , Postal Service , Poultry/microbiology , Salmonella Infections/epidemiology , Salmonella/isolation & purification , Agriculture , Animals , Child , Cluster Analysis , Commerce , Humans , Ohio , Risk , Salmonella/classification , Salmonella Infections/transmission , Time Factors , United States/epidemiology
14.
MMWR Morb Mortal Wkly Rep ; 63(10): 222, 2014 Mar 14.
Article in English | MEDLINE | ID: mdl-24622287

ABSTRACT

In early 2013, four clusters of human Salmonella infections were identified through PulseNet, the national molecular subtyping network for foodborne bacteria. Many of the ill persons in these four clusters reported contact with live poultry, primarily chicks and ducklings, from a single mail-order hatchery; therefore, these investigations were merged. During March 4-October 9, 2013, a total of 158 persons infected with outbreak strains of Salmonella serotypes Infantis, Lille, Newport, and Mbandaka were reported from 30 states.


Subject(s)
Disease Outbreaks , Postal Service , Poultry/microbiology , Salmonella Infections/epidemiology , Salmonella/isolation & purification , Agriculture , Animals , Commerce , Humans , Ohio , Risk , Salmonella/classification , Salmonella Infections/transmission , Time Factors , United States/epidemiology
15.
Clin Infect Dis ; 58(10): 1432-8, 2014 May.
Article in English | MEDLINE | ID: mdl-24501387

ABSTRACT

Poultry are well recognized as possible carriers of Salmonella species. As part of the local foods movement, backyard poultry flocks have increased in popularity in recent years. Between 1996 and 2012, 45 outbreaks of human Salmonella infections linked to live poultry from mail-order hatcheries were documented. This review examines the history of live poultry-associated salmonellosis in humans in the United States, the current status of the issue, and what can be done to help prevent these illnesses. An integrated One Health approach involving the mail-order hatchery industry, feed stores, healthcare providers, veterinarians, and backyard flock owners is needed to help prevent live poultry-associated salmonellosis.


Subject(s)
Disease Outbreaks/prevention & control , Poultry/microbiology , Salmonella Infections, Animal/epidemiology , Salmonella Infections, Animal/transmission , Salmonella Infections/prevention & control , Salmonella Infections/transmission , Animals , Humans , Public Health , Salmonella/physiology , Salmonella Infections/epidemiology , United States/epidemiology , Zoonoses
16.
Emerg Infect Dis ; 20(2): 280-3, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24447835

ABSTRACT

Inhalation anthrax occurred in a man who vacationed in 4 US states where anthrax is enzootic. Despite an extensive multi-agency investigation, the specific source was not detected, and no additional related human or animal cases were found. Although rare, inhalation anthrax can occur naturally in the United States.


Subject(s)
Anthrax/microbiology , Bacillus anthracis/genetics , Inhalation Exposure , Respiratory Tract Infections/microbiology , Spores, Bacterial/pathogenicity , Animals , Anthrax/diagnosis , Bacillus anthracis/isolation & purification , Humans , Male , Middle Aged , Multilocus Sequence Typing , Respiratory Tract Infections/diagnosis , Travel , United States
17.
Clin Infect Dis ; 57 Suppl 1: S4-S11, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23794729

ABSTRACT

BACKGROUND. During August 2011-April 2012, 13 human infections with influenza A(H3N2) variant (H3N2v) virus were identified in the United States; 8 occurred in the prior 2 years. This virus differs from previous variant influenza viruses in that it contains the matrix (M) gene from the Influenza A(H1N1)pdm09 pandemic influenza virus. METHODS. A case was defined as a person with laboratory-confirmed H3N2v virus infection. Cases and contacts were interviewed to determine exposure to swine and other animals and to assess potential person-to-person transmission. RESULTS. Median age of cases was 4 years, and 12 of 13 (92%) were children. Pig exposure was identified in 7 (54%) cases. Six of 7 cases with swine exposure (86%) touched pigs, and 1 (14%) was close to pigs without known direct contact. Six cases had no swine exposure, including 2 clusters of suspected person-to-person transmission. All cases had fever; 12 (92%) had respiratory symptoms, and 3 (23%) were hospitalized for influenza. All 13 cases recovered. CONCLUSIONS. H3N2v virus infections were identified at a high rate from August 2011 to April 2012, and cases without swine exposure were identified in influenza-like illness outbreaks, indicating that limited person-to-person transmission likely occurred. Variant influenza viruses rarely result in sustained person-to-person transmission; however, the potential for this H3N2v virus to transmit efficiently is of concern. With minimal preexisting immunity in children and the limited cross-protective effect from seasonal influenza vaccine, the majority of children are susceptible to infection with this novel influenza virus.


Subject(s)
Disease Outbreaks , Influenza A Virus, H3N2 Subtype/isolation & purification , Influenza, Human/epidemiology , Adolescent , Adult , Animals , Child , Child, Preschool , Female , Humans , Infant , Influenza A Virus, H1N1 Subtype/genetics , Influenza A Virus, H3N2 Subtype/genetics , Influenza, Human/transmission , Male , Middle Aged , Orthomyxoviridae Infections/transmission , Orthomyxoviridae Infections/veterinary , Swine , Swine Diseases/transmission , United States/epidemiology
18.
Philos Trans A Math Phys Eng Sci ; 371(1993): 20120424, 2013 Jun 28.
Article in English | MEDLINE | ID: mdl-23690635

ABSTRACT

In this paper, we deal with the theoretical framework for a single-walled carbon nanotube serving as a virus or bacterium sensor, with the complicating influences of non-locality and surface effects taken into account. It is demonstrated that these effects are not negligible as is often assumed in the literature; they may greatly influence both the vibration behaviour as well as the identification process of the virus or bacterium.


Subject(s)
Biosensing Techniques , Nanotubes, Carbon , Viruses/isolation & purification , Models, Theoretical
19.
Behav Pharmacol ; 24(3): 155-63, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23549451

ABSTRACT

Relative reinforcing effects of different ethanol and different cocaine doses were studied under concurrent independent fixed-ratio (FR) schedules and concurrent nonindependent FR schedules with rhesus monkeys. Nonindependent FR schedules differed from independent FR schedules in that responses on either side counted towards the FR requirements of two concurrently presented choices. Thus, responses on the right operandum counted toward completion of both right and left FR schedules and, symmetrically, responses on the left did the same. Nonindependent schedules allow the number of responses per drug delivery to vary considerably, unlike independent schedules, thereby making the number of responses per delivery a sensitive dependent variable. In contrast, standard independent schedules do not allow responses per drug delivery to vary; the required number of responses is an independent variable. Three rhesus monkeys were subjects, and choices between different doses of ethanol or cocaine were studied. Larger doses maintained higher response rates than smaller doses - consistent with previous choice studies. By using nonindependent schedules, however, graded responses per drug delivery and increased switching between sides were obtained, providing additional data and useful measures of choice.


Subject(s)
Central Nervous System Depressants/administration & dosage , Choice Behavior/physiology , Cocaine/administration & dosage , Dopamine Uptake Inhibitors/administration & dosage , Ethanol/administration & dosage , Reinforcement Schedule , Animals , Conditioning, Operant/drug effects , Discrimination, Psychological/drug effects , Dose-Response Relationship, Drug , Macaca mulatta , Male , Photic Stimulation , Self Administration
20.
N Engl J Med ; 366(22): 2065-73, 2012 May 31.
Article in English | MEDLINE | ID: mdl-22646629

ABSTRACT

BACKGROUND: Outbreaks of human salmonella infections are increasingly associated with contact with live poultry, but effective control measures are elusive. In 2005, a cluster of human salmonella Montevideo infections with a rare pattern on pulsed-field gel electrophoresis (the outbreak strain) was identified by PulseNet, a national subtyping network. METHODS: In cooperation with public health and animal health agencies, we conducted multistate investigations involving patient interviews, trace-back investigations, and environmental testing at a mail-order hatchery linked to the outbreak in order to identify the source of infections and prevent additional illnesses. A case was defined as an infection with the outbreak strain between 2004 and 2011. RESULTS: From 2004 through 2011, we identified 316 cases in 43 states. The median age of the patient was 4 years. Interviews were completed with 156 patients (or their caretakers) (49%), and 36 of these patients (23%) were hospitalized. Among the 145 patients for whom information was available, 80 (55%) had bloody diarrhea. Information on contact with live young poultry was available for 159 patients, and 122 of these patients (77%) reported having such contact. A mail-order hatchery in the western United States was identified in 81% of the trace-back investigations, and the outbreak strain was isolated from samples collected at the hatchery. After interventions at the hatchery, the number of human infections declined, but transmission continued. CONCLUSIONS: We identified a prolonged multistate outbreak of salmonellosis, predominantly affecting young children and associated with contact with live young poultry from a mail-order hatchery. Interventions performed at the hatchery reduced, but did not eliminate, associated human infections, demonstrating the difficulty of eliminating salmonella transmission from live poultry.


Subject(s)
Chickens/microbiology , Disease Outbreaks , Ducks/microbiology , Postal Service , Poultry Diseases/transmission , Salmonella Infections/epidemiology , Adolescent , Adult , Aged , Aged, 80 and over , Animal Husbandry , Animals , Child , Child, Preschool , Female , Humans , Infant , Male , Middle Aged , Salmonella Infections/transmission , United States/epidemiology , Young Adult
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