bluuebunny/crossref_metadata_2025 huggingface dataset:
On the distance between the distributions of random sums
Authors: Roos Bero , Pfeifer Dietmar
Published: April 2003

In this paper, we consider the total variation distance between the distributions of two random sumsSMandSNwith different random summation indicesMandN. We derive upper bounds, some of which are sharp. Further, bounds with so-called magic factors are possible. Better results are possible whenMandNare stochastically or stop-loss ordered. It turns out that the solution of this approximation problem strongly depends on how many of the first moments ofMandNcoincide. As approximations, we therefore choose suitable finite signed measures, which coincide with the distribution of the approximating random sumSNifMandNhave the same first moments.
Perturbed Markov chains
Authors: Solan Eilon , Vieille Nicolas
Published: April 2003

We study irreducible time-homogenous Markov chains with finite state space in discrete time. We obtain results on the sensitivity of the stationary distribution and other statistical quantities with respect to perturbations of the transition matrix. We define a new closeness relation between transition matrices, and use graph-theoretic techniques, in contrast with the matrix analysis techniques previously used.
On the geometric ergodicity of hybrid samplers
Authors: Fort G. , Moulines E. , Roberts G. O. , Rosenthal J. S.
Published: April 2003

In this paper, we consider the random-scan symmetric random walk Metropolis algorithm (RSM) onℝd. This algorithm performs a Metropolis step on just one coordinate at a time (as opposed to the full-dimensional symmetric random walk Metropolis algorithm, which proposes a transition on all coordinates at once). We present various sufficient conditions implyingV-uniform ergodicity of the RSM when the target density decreases either subexponentially or exponentially in the tails.
A new theorem on the existence of invariant distributions with applications to ARCH processes
Authors: Kazakevičius Vytautas , Leipus Remigijus
Published: April 2003

A new theorem on the existence of an invariant initial distribution for a Markov chain evolving on a Polish space is proved. As an application of the theorem, sufficient conditions for the existence of integrated ARCH processes are established. In the case where these conditions are violated, the top Lyapunov exponent is shown to be zero.
Birth-death processes with an instantaneous reflection barrier
Authors: Chen Anyue , Liu Kai
Published: April 2003

A new structure with the special property that an instantaneous reflection barrier is imposed on the ordinary birth—death processes is considered. An easy-checking criterion for the existence of such Markov processes is first obtained. The uniqueness criterion is then established. In the nonunique case, all the honest processes are explicitly constructed. Ergodicity properties for these processes are investigated. It is proved that honest processes are always ergodic without necessarily imposing any extra conditions. Equilibrium distributions for all these ergodic processes are established. Several examples are provided to illustrate our results.
Analysis of the fluid weighted fair queueing system
Authors: Guillemin Fabrice , Mazumdar Ravi , Dupuis Alain , Boyer Jacqueline
Published: April 2003

We analyse in this paper the fluid weighted fair queueing system with two classes of customers, who arrive according to Poisson processes and require arbitrarily distributed service times. In a first step, we express the Laplace transform of the joint distribution of the workloads in the two virtual queues of the system by means of unknown Laplace transforms. Such an unknown Laplace transform is related to the distribution of the workload in one queue provided that the other queue is empty. We explicitly compute the unknown Laplace transforms by means of a Wiener—Hopf technique. The determination of the unknown Laplace transforms can be used to compute some performance measures characterizing the system (e.g. the mean waiting time for each class) which we compute in the exponential service case.
On the integral of the workload process of the single server queue
Authors: Borovkov A. A. , Boxma O. J. , Palmowski Z.
Published: April 2003

This paper is devoted to a study of the integral of the workload process of the single server queue, in particular during one busy period. Firstly, we find asymptotics of the area 𝒜 swept under the workload process W(t) during the busy period when the service time distribution has a regularly varying tail. We also investigate the case of a light-tailed service time distribution. Secondly, we consider the problem of obtaining an explicit expression for the distribution of 𝒜. In the general GI/G/1 case, we use a sequential approximation to find the Laplace—Stieltjes transform of 𝒜. In the M/M/1 case, this transform is obtained explicitly in terms of Whittaker functions. Thirdly, we consider moments of 𝒜 in the GI/G/1 queue. Finally, we show asymptotic normality of .
A clustering law for some discrete order statistics
Authors: Sethuraman Sunder
Published: April 2003

Let X1, X2, …, Xn be a sequence of independent, identically distributed positive integer random variables with distribution function F. Anderson (1970) proved a variant of the law of large numbers by showing that the sample maximum moves asymptotically on two values if and only if F satisfies a ‘clustering’ condition, In this article, we generalize Anderson's result and show that it is robust by proving that, for any r ≥ 0, the sample maximum and other extremes asymptotically cluster on r + 2 values if and only if Together with previous work which considered other asymptotic properties of these sample extremes, a more detailed asymptotic clustering structure for discrete order statistics is presented.
Characterizing losses during busy periods in finite buffer systems
Authors: Peköz Erol A. , Righter Rhonda , Xia Cathy H.
Published: April 2003

For multiple-server finite-buffer systems with batch Poisson arrivals, we explore how the distribution of the number of losses during a busy period changes with the buffer size and the initial number of customers. We show that when the arrival rate equals the maximal service rate (ρ= 1), as the buffer size increases the number of losses in a busy period increases in the convex sense, and whenρ> 1, as the buffer size increases the number of busy period losses increases in the increasing convex sense. Also, the number of busy period losses is stochastically increasing in the initial number of customers. A consequence of our results is that, whenρ= 1, the mean number of busy period losses equals the mean batch size of arrivals regardless of the buffer size. We show that this invariance does not extend to general arrival processes.
Some memoryless bandit policies
Authors: Peköz Erol A.
Published: April 2003

We consider a multiarmed bandit problem, where each arm when pulled generates independent and identically distributed nonnegative rewards according to some unknown distribution. The goal is to maximize the long-run average reward per pull with the restriction that any previously learned information is forgotten whenever a switch between arms is made. We present several policies and a peculiarity surrounding them.
The asymptotic joint normality of the numbers of upper records, lower records and inversions in a random sequence
Authors: Chao Chern-Ching , Chen Yi-Liang , Cheng Wei-Hou
Published: April 2003

We derive the asymptotic joint normality, by a martingale approach, for the numbers of upper records, lower records and inversions in a random sequence.
A further extension of the generalized burn-in model
Authors: Cha Ji Hwan
Published: April 2003

In this paper, the generalized burn-in and replacement model considered by Cha (2001) is further extended to the case in which the probability of Type II failure is time dependent. Two burn-in procedures are considered and they are compared in cases when both the procedures are applicable. Under some mild conditions on the failure rate function r(t) and the Type II failure probability function p(t), the problems of determining optimal burn-in time and optimal replacement policy are considered.
New Type of Monodispersed Gold Nanoparticles Capped by Myristate and PPh3 Ligands Prepared by Controlled Thermolysis of [Au(C13H27COO)(PPh3)]
Authors: Yamamoto Mari , Nakamoto Masami
Published: April 2003

Controlled thermolysis of gold(I) complex, [Au(C13H27COO)(PPh3)], at 180 °C for 5 h under an N2 atmosphere affords the new type of monodispersed spherical gold nanoparticles capped by myristate and a small amount of PPh3 ligands (average diameter 23 ± 1.5 nm), in spite of no use of solvent, reducing agent and stabilizer.
Comparing Methods of Establishing the aPTT Therapeutic Range of Heparin
Authors: Liepman Claire I , Koerber John M , Mattson Joan C , Westley Susan J , Smythe Maureen A
Published: April 2003

BACKGROUND:

The American College of Chest Physicians (ACCP) recommends that the activated partial thromboplastin time (aPTT) therapeutic range for unfractionated heparin be defined as the aPTT corresponding to a heparin concentration of 0.3–0.7 μ/mL by heparin anti-factor Xa assay. This recommendation suggests that a therapeutic range defined in this manner should be superior to traditional empiric therapeutic ranges of 1.5–2.5 times the control. A pilot study was conducted to evaluate the ACCP recommendation for heparin monitoring.

OBJECTIVE:

To compare heparin dosage adjustments guided by a heparin concentration–derived therapeutic range (HCDTR) with those influenced by traditional empiric therapeutic ranges for the aPTT.

METHODS:

This study was conducted in 2 phases. In phase 1, the various aPTT therapeutic ranges were established and/or defined. The first empiric therapeutic range (E1) was established by performing an aPTT test on healthy volunteers. This E1 was defined as 1.5–2.5 times the mean normal aPTT. A second empiric therapeutic range (E2) was defined as 1.5–2.5 times the patient's baseline aPTT. The aPTT HCDTR had been defined in a previous study as 48–61 seconds. In phase 2, heparin dosage adjustment decisions guided by each empiric range and the HCDTR for the aPTT were compared with heparin dosage adjustment decisions guided by actual heparin concentrations. Decisions were in agreement when both the aPTT result and plasma heparin concentration indicated the same dosage change. Forty patients had a bedside aPTT determined prior to receiving continuous infusion heparin and again within 48 hours of heparin initiation. Plasma heparin concentration by anti-factor Xa assay was performed on the blood samples obtained after heparin initiation. Heparin dosage adjustment decisions were evaluated by determining the agreement of each aPTT test result with the corresponding plasma heparin concentration. An overall level of agreement (defined as the % of decisions that were in agreement) for each aPTT therapeutic range was determined.

RESULTS:

The level of agreement in dosage adjustment decisions between heparin concentration and E1, E2, and HCDTR was 28/40 (70%), 28/39 (72%), and 23/40 (58%), respectively (p = 0.34). Heparin dosage adjustment decisions based on an aPTT HCDTR did not significantly differ from heparin dosage adjustment decisions guided by traditional empiric therapeutic ranges for a bedside aPTT.

CONCLUSIONS:

This pilot study showed similar heparin dosage adjustment decisions using an empiric aPTT therapeutic range versus a heparin concentration–derived aPTT therapeutic range.
Absorption of Enteral Recombinant Human Erythropoietin by Neonates
Authors: Juul Sandra E , Christensen Robert D
Published: April 2003

BACKGROUND:

Erythropoietin (EPO) is present in amniotic fluid, colostrum, and human milk. One possible function of ingested EPO might be to stimulate erythropoiesis. However, it is unclear whether human neonates absorb recombinant human erythropoietin (rhEPO) after oral administration.

OBJECTIVE:

To determine whether circulating EPO concentrations increase following enteral administration of rhEPO to neonates.

METHODS:

The study was designed as a 2-center prospective, blinded, randomized, 2 times 2 crossover study, with each infant receiving 1 dose of rhEPO 1000 units/kg and 1 dose of placebo. Serum EPO concentrations were measured at baseline, 2, and 4 hours following study drug administration. The rhEPO and placebo dosing were separated by a mean of 72 hours. Analysis was stratified by gestational age (≤35 wk, >35 wk) and feeding type (human milk, infant formula).

RESULTS:

No significant change in serum EPO concentration was identified at 2 or 4 hours following enteral administration of rhEPO.

CONCLUSIONS:

Enteral administration of a large dose of rhEPO to neonates <4 months of age did not result in increased circulating EPO concentrations at 2 or 4 hours following dosing, regardless of whether it was administered in human milk or infant formula.
Interaction between Warfarin and the Herbal Product Quilinggao
Authors: Wong Anna LN , Chan Thomas YK
Published: April 2003

OBJECTIVE:

To describe a patient with loss of anticoagulation control and bleeding after consumption of the combination herbal product quilinggao.

CASE SUMMARY:

A 61-year-old man who was stable on warfarin therapy regularly consumed a jelly-like herbal product called quilinggao (“essence of tortoise shell”). Five days after the daily consumption of a second brand of quilinggao, he developed easy gum bleeding, epistaxis, and skin bruising with an international normalized ratio (INR) >6.0. Warfarin therapy was temporarily withdrawn until the INR decreased to 1.9. On the day of hospital discharge, he took a third brand of quilinggao against medical advice. Three days later, his INR was 5.2. Warfarin therapy was again temporarily withheld and the patient counseled about an apparent herb–warfarin interaction. He could not remember the name of the third brand of quilinggao.

DISCUSSION:

Quilinggao is a very popular Chinese herbal product. There are many different brands, and the composition of herbal products varies between manufacturers. Chuanbeimu ( Fritillaria cirrhosa) in the first brand and beimu ( Fritillaria spp.), chishao ( Paeoniae rubra, Chinese peony), jinyinhua ( Lonicera japonica), and jishi ( Poncirus trifoliata) in the second brand of quilinggao have antiplatelet and/or antithrombotic effects. Loss of anticoagulation control occurred after consumption of the second and third brands of quilinggao, possibly due to the presence of a greater number of interacting herbs. An objective causality assessment revealed that the observed reaction was highly probable to be related to the ingestion of the second and third brands of quilinggao.

CONCLUSIONS:

Quilinggao contains herbal ingredients that can interact with warfarin. Patients on warfarin therapy should be discouraged from taking herbal medicines, especially preparations that are already known to have antiplatelet and antithrombotic effects.
Self‐discrepancies, attentional bias and persecutory delusions
Authors: Kinderman Peter , Prince Sharon , Waller Glenn , Peters Emmanuelle
Published: April 2003

Background: Persecutory delusions appear to involve abnormal attentional biases to threat‐related information, particularly information related to the self. The present study aimed to investigate attentional biases to different types of perceived threat and changes in self‐perception in response to exposure to such threat‐related material.

Method: Discrepancies between actual self, ideal self and perceived others' self‐representations were assessed in three groups of participants; 13 people experiencing persecutory delusions, 11 people in a psychiatric comparison group, and 13 in a non‐psychiatric comparison group. An adaptation of the emotional Stroop task was then used as an experimental manipulation of attentional bias to five different types of threat (sociotropic, autonomic, physical, ego threats from others, and self‐directed ego threats). Self‐discrepancies were then again assessed.

Results: Before administration of the emotional Stroop task, there were no significant differences between the groups in terms of their self‐actual: self‐ideal and self‐actual: other‐actual discrepancies. However, after the administration of the Stroop task, significant differences between the clinical groups were observed, mirroring significant reductions in self‐actual: self‐ideal discrepancies and significant increases in self‐actual: other‐actual discrepancies in the paranoid participants.

Conclusions: This paper is novel in repeating the assessment of self‐discrepancies after the processing of threat‐related information. These findings are consistent with Bentall, Kinderman, and Kaney's (1994) model of paranoid ideation and findings reported by Kinderman and Bentall (2000).
Fear reduction during in vivo exposure to blood‐injection stimuli: Distraction vs. attentional focus
Authors: Oliver Naomi S. , Page Andrew C.
Published: April 2003

Objective: This study extends Penfold and Page's (1999) finding that exposure plus distraction enhanced within‐session fear reduction to a phobic stimulus by examining whether the within‐session advantage could be replicated and translated into longer‐term gains.

Design: To test the effects of distraction, participants were assigned randomly to one of three experimental conditions; exposure plus focusing, exposure plus distraction, or exposure alone.

Method: Blood‐injection fearful participants (N = 48) were assigned randomly to receive 3 weekly sessions of 10‐min exposure under one of the experimental conditions.

Results: Consistent with the previous finding, exposure plus distraction showed the greatest within‐session fear reduction. Participants in the exposure plus distraction condition also reported the greatest reduction in fear between sessions, at post‐treatment, and at 1‐month follow‐up. Furthermore, participants in the exposure plus distraction condition reported continued increases in perceived control over their anxiety during the month following the exposure sessions.

Conclusions: The data suggest that conversation is a distraction that can increase perceived control over anxiety and assists anxiety reduction.
The cognitive specificity of associative responses in patients with chronic pain
Authors: McKellar John D. , Clark Michael E. , Shriner Jan
Published: April 2003

Objective: Previous studies have found evidence of an associative response bias for patients with chronic pain. This body of research is not clear, however, on whether this bias is specific to patients with chronic pain, or whether the bias is specific to pain stimuli or illness/disability stimuli.

Design: This is a cross‐sectional study involving the comparison of selected groups (chronic pain, acute pain, and medical‐staff controls).

Method: This study included 80 male participants with chronic pain, 50 male participants with acute pain, and 49 male participants who served as medical staff controls. All participants completed the Beck Depression Inventory, the State‐Trait Anxiety Inventory, a pain intensity VAS, and the single‐word associate homographic response task.

Results: Evidence was found for the specificity of pain responses to homographic pain stimuli as the chronic pain group produced more of these responses than the two comparison groups.

Conclusions: These findings were seen as providing evidence for an associative response bias. This bias appears specific to pain‐related stimuli and reflects the cumulative effects of pain over a period of time.
Coping effectiveness training reduces depression and anxiety following traumatic spinal cord injuries
Authors: Kennedy P. , Duff J. , Evans M. , Beedie A.
Published: April 2003

Objective: To extend the findings of a pilot study that evaluated a brief group‐based psychological intervention aimed at improving psychological adjustment, self‐perception and enhancing adaptive coping following spinal cord injury. The theoretical underpinnings of the Coping Effectiveness Training (CET) Programme are Lazarus and Folkman's (1984) cognitive theory of stress and coping, and cognitive behavioural therapy techniques.

Design: A controlled trial comparing patients that received the CET intervention with matched controls on measures of psychological adjustment and coping.

Method: A total of 45 intervention group participants and 40 matched controls were selected from inpatients at a hospital‐based spinal cord injury centre. Outcome measures of anxiety and depression, self‐perception and coping were collected before, immediately after and 6 weeks following the intervention.

Results: Intervention group participants showed a significant reduction in depression and anxiety, compared to the matched controls following the intervention. There was no evidence of a significant change in the pattern of coping strategies used by the intervention group compared to controls. The intervention group alone completed measures of self‐perception. There was a significant decrease in the discrepancy between participants' ‘ideal’ self and ‘as I am’, and between ‘as I would be without the injury’ and ‘as I am’ following the intervention and at follow‐up. Significant correlations were also found between self‐perception, and anxiety and depression over time.

Conclusions: These results confirm the findings of the pilot study, that the CET intervention facilitated a significant improvement in psychological adjustment to spinal cord injury. It is proposed that this improvement may be understood in terms of changing participants' negative appraisals of the implications of spinal cord injury with the result of increasing the perceived manageability of its consequences. Such decatastrophizing alters appraisals which are associated with current mood. Participants found shared discussion and problem‐solving to be particularly helpful. Avenues for further research are discussed.
Assessing expressed emotion in mothers of preschool AD/HD children: Psychometric properties of a modified speech sample
Authors: Daley D. , Sonuga‐Barke E. J. S. , Thompson M.
Published: April 2003

Objective: To examine the reliability and validity of a modified coding measure of expressed emotion (Preschool Five Minute Speech Sample [PFMSS]), suitable for parents of preschool AD/HD children.

Design: Mothers of preschool AD/HD children identified through a three‐stage screening programme were compared with mothers of non‐AD/HD children on the PFMSS.

Method: Mothers of 80 AD/HD and 20 non‐AD/HD children participated in the PFMSS. They had 10 mins of play interaction with their child and completed the Feelings on Parenting scales from the Family Impact Questionnaire.

Results: With the exception of emotional over‐involvement, the PFMSS demonstrated acceptable code‐recode and inter‐rater reliability, and adequate test‐retest reliability. It also demonstrated acceptable validity, being associated with less affection and greater maternal direction during play interaction and discriminated between the parents of preschool AD/HD and non‐AD/HD children.

Conclusion: This study shows that in a revised form, the Five Minute Speech Sample can provide a useful measure of expressed emotion during the preschool period.
The impact of maternal mental health and child's behavioural difficulties on attributions about child behaviours
Authors: Cornah Deborah , Sonuga‐Barke Edmund , Stevenson Jim , Thompson Margaret
Published: April 2003

The effects of maternal mental health and child's behavioural difficulties upon mothers' attributions for negative child behaviour were examined. A community sample of 70 mothers of children aged about 9 years were interviewed in depth and the interviews transcribed. Transcripts were analysed for spontaneous attributions which were subsequently coded on the dimensions of internality, controllability, stability, universality and globality. Mothers with mental health problems made the same number of attributions about negative behaviours as normal mothers. However, more internal‐to‐self and global attributions were made by the group with mental health problems. This pattern was demonstrated regardless of the child's level of behavioural difficulties. The increase in negative attributions by mothers with mental health problems is not the result of the association between maternal mental health and child's behavioural difficulties. Mothers with mental health problems do not explain their child's negative behaviours in a way that is typical of normal mothers, and reasons for this are discussed.
Preliminary analysis of the psychometric properties of the Mood, Interest & Pleasure Questionnaire (MIPQ) for adults with severe and profound learning disabilities
Authors: Ross Elaine , Oliver Chris
Published: April 2003

Objective: There are few reliable and valid methods for assessing emotional constructs in adults with severe and profound learning disabilities who are unable to self report. The aims of this study were to develop an informant questionnaire on affect for use in relation to adults with severe and profound learning disabilities and to examine its psychometric properties.

Method: The Mood, Interest & Pleasure Questionnaire (MIPQ) is a 25‐item Likert scale questionnaire with two subscales (mood and interest & pleasure). The MIPQ and the Aberrant Behavior Checklist were completed on 53 participants with severe or profound learning disabilities, who were partly or non‐verbal. Of these, 23 participants (43%) were included in an examination of test‐retest and inter‐rater reliability of the MIPQ.

Results: Reliability of the MIPQ was good for subscales and total score: test‐retest and inter‐rater reliability coefficients for the total score were .87 and .76, respectively. Internal consistency was excellent (.94). A significant correlation between the MIPQ total score and the Aberrant Behavior Checklist's ‘lethargy, social withdrawal’ subscale provided preliminary evidence of construct validity (r (48) = ‐.59, p < .001).

Conclusions: A preliminary analysis of the psychometric properties of the MIPQ is encouraging and further validation of the measure is warranted. The measure might be used to examine depression in people with severe and profound learning disabilities as well as in investigations of issues such as quality of life.
Detection of children's malingering on Raven's Standard Progressive Matrices
Authors: McKinzey R. Kim , Prieler Jörg , Raven John
Published: April 2003

A formula for detecting faked Raven's SPM profiles was cross‐validated on 44 children and adolescents (ages 7–17). It yielded a false negative rate of 64%. However, a rule using three very easy items (i.e., any of A3, A4 or B1 missed) yielded a hit rate of 95%, with 5% false positive and negative rates. All but two of the participants were able to produce lower scores when asked to fake the test.
The relationship between illness attributions and attributional style in Chronic Fatigue Syndrome
Authors: Creswell Cathy , Chalder Trudie
Published: April 2003

Objective: To examine the relationship between illness attributions and general attributional style in Chronic Fatigue Syndrome (CFS).

Method: Participants with CFS answered questions on their explanation for their illness and completed the Attributional Style Questionnaire (parallel form).

Results: Of the participants, 58.3% attributed their illness to predominantly physical factors. A significant relationship was found between the presence of a self‐serving attributional style and illness attributions.

Conclusion: Illness attributions were associated with an individual's general attributional style. It is suggested that illness attributions may be less important with regards prognosis than, for example, other variables which influence a person's general view of the world.
Angiomatosis, A Newly Recognized Disease in Atlantic Bottlenose Dolphins (Tursiops truncatus) from the Gulf of Mexico
Authors: Turnbull B. S. , Cowan D. F.
Published: April 2003

A new disease, angiomatosis, was recognized in 25 of 54 (46.3%) Atlantic bottlenose dolphins ( Tursiops truncatus) necropsied after being stranded along the Texas Gulf coast during 1991-1996. Angiomatosis was first recognized by the authors in 1992 and has increased in incidence and severity, affecting 100% of juveniles and adults. This disease is characterized by proliferation of small, thick-walled blood vessels diffusely throughout the lungs, without inflammation, exudation, or alveolar hemorrhage. The vascular proliferation also occurs in lung-associated and other visceral lymph nodes. Hemangiomas frequently occur in affected lymph nodes and occasionally in the lungs. The vascular proliferation reduces airspace and may occlude small airways. Angiomatosis appears to be a broad-field defect of vascular endothelium. Although this process appears to be an increasingly important factor in the morbidity of T. truncatus, its etiology has not been determined.
Experimental Infection of Pregnant Cows with Bacillus licheniformis Bacteria
Authors: Agerholm J. S. , Jensen N. E. , Dantzer V. , Jensen H. E. , Aarestrup F. M.
Published: April 2003

To study the abortifacient potential and fetoplacental tropism of Bacillus licheniformis bacteria, eight cows in the sixth to eighth month of gestation were inoculated intravenously either once ( n = 4) or on four successive days ( n = 4) with B. licheniformis at doses ranging from 109 to 1012 colony-forming units. Cows were euthanatized and necropsied prior to abortion ( n = 2), at the time of abortion ( n = 2), or at calving ( n = 4). Live-born calves ( n = 5) were euthanatized immediately after delivery and necropsied. B. licheniformis was reisolated from placentomes/endometrium in six of eight (75%) cows and from one fetus aborted 43 days after inoculation. Lesions associated with B. licheniformis were restricted to the pregnant uterus, with the exception of one cow, which developed pneumonia. Necrosis in the fetal compartment of the placenta were present in three of four (75%) cows of both inoculation groups. Lesions were mainly restricted to fetal membranes and especially to the fetal side of the placentomes. Necrosis and diffuse neutrophil infiltrations of both villi and intervillous areas occurred in the fetal part of the placenta, and the placentomal interface was distended by bacteria, neutrophils, erythrocytes, and debris. Within trophoblasts, bacteria were located both free in the cytoplasm and in cytoplasmatic vesicles. Inflammation was present in three of eight (38%) calves. Placental and fetal lesions were similar to those found in cases of spontaneous abortions associated with B. licheniformis. The abortifacient potential of B. licheniformis and the tropism for the bovine placenta is demonstrated here for the first time.
Bacterial Isolation, Immunological Response, and Histopathological Lesions during the Early Subclinical Phase of Experimental Infection of Goat Kids with Mycobacterium avium subsp. paratuberculosis
Authors: SigurdardÓttir Ó. G. , Press C. McL. , Saxegaard F. , Evensen Ø.
Published: April 2003

The diagnosis of Mycobacterium avium subsp. paratuberculosis infection is difficult, especially in the early stages of disease. This is due to the long incubation period, the variable lag phase associated with bacterial proliferation, and the multifocal distrbution of slowly developing lestion. There are few previous studies of the early stages of experimental paratuberculosis in goats. In the present study, the ability of conventional diagnostic methods to detect M. a. paratuberculosis infection during the early stages of infection was assessed. Eight goat kids were experimentally infected with M. a. paratuberculosis and subjected to a series of immunological and bacteriological tests before being euthanatized at various times postinfection. At postmortem examination, the ages of the kids ranged from 1 1/2 to 12 months. Of the eight goats infected, three had histo-pathological evidence of paratuberculosis. Two of these goats were positive with bacteriology, but only one was also positive with all immunological tests. One animal had a positive immunological response, but infection could not be demonstrated by bacteriologic or histopathologic examination. Histopathologic lesions were found in the jejunum, in the ileum, and in one mesenteric lymph node, but only the mesenteric lymph nodes and one retropharyngeal lymph node gave positive results following bacteriologic culture. The disparity between the localization of histopathologic lesions and bacteriologic results emphasizes the need for exhaustive sampling to confirm a diagnosis during the early phase of an infection. It also highlights the need for a better understanding of the biology of M. a. paratuberculosis and its interaction with the immune system of the host.
Simultaneous Occurrence of Multiple Neoplasms and Hyperplasias in the Adrenal and Thyroid Gland of the Horse Resembling Multiple Endocrine Neoplasia Syndrome: Case Report and Retrospective Identification of Additional Cases
Authors: De Cock H. E. V. , Maclachlan N. J.
Published: April 2003

Neoplastic and hyperplastic disorders that affect multiple endocrine tissues in a single individual are well described in humans but less so in domestic animals. Multiple endocrine neoplasia (MEN) in humans is a genetically determined syndrome characterized by the appearance of benign or malignant proliferations within two or more endocrine glands. The primary endocrine tumors that are characteristic of MEN arise from cells that share the capacity for amine precursor uptake and decarboxylation. Here we describe the case of a 22-year-old Thoroughbred mare that died during an unattended parturition and subsequently was presented for necropsy at the University of California, Davis, Veterinary Medical Teaching Hospital. A C-cell (medullary) thyroid adenoma, pheochromocytoma, and multicentric bilateral nodular hyperplasia of the adrenal medulla were present, findings that are remarkably similar to those of human MEN syndrome. Mortality during pregnancy in women with undiagnosed pheochromocytoma is high (approximately 50%), typically because of hypertension and/or hemorrhage associated with catecholamine release from the tumor. Similarly, the mare in this report died of hemorrhage subsequent to parturition. A retrospective evaluation of endocrine tumors in horses that underwent necropsy at the Veterinary Medical Teaching Hospital from 1987 to 1997 was undertaken to identify additional possible cases of MEN in horses. Data from this retrospective evaluation suggest that co-existence of hyperplasias and neoplasias of the thyroid and adrenal glands, similar to MEN syndrome of humans, also occurs with some frequency in the horse.
Parvovirus Infection of Keratinocytes as a Cause of Canine Erythema Multiforme
Authors: Favrot C. , Olivry T. , Dunston S. M. , Degorce-Rubiales F. , Guy J. S.
Published: April 2003

Erythema multiforme major was diagnosed in a dog with necrotizing parvoviral enteritis. Skin lesions consisted of ulceration of the footpads, pressure points, mouth, and vaginal mucosa; vesicles in the oral cavity; and erythematous patches on the abdomen and perivulvar skin. Microscopic examination of mucosal and haired skin specimens revealed lymphocyte-associated keratinocyte apoptosis at various levels of the epidermis. Basophilic cytoplasmic inclusions were seen in basal and suprabasal keratinocytes. Immunohistochemical staining, performed with canine parvovirus-2-specific monoclonal antibodies, confirmed the parvovirus nature of the inclusions in the nucleus and cytoplasm of oral and skin epithelial cells. This is the first case of canine erythema multiforme reported to be caused by a viral infection of keratinocytes. This case study indicates that the search for epitheliotropic viruses should be attempted in cases of erythema multiforme in which a drug cause cannot be identified.
Small Intestine Large Granular Lymphoma in a Horse
Authors: Herraez P. , Berridge B. , Marsh P. , Weeks B. , Ramiro-Ibañez F.
Published: April 2003

A 12-year-old Appaloosa gelding was referred to the Texas Veterinary Medical Center with a history of chronic diarrhea and weight loss. At necropsy, numerous oval, craterlike ulcers were observed throughout the small intestine. Histologically, these lesions were composed of a neoplastic proliferation of round cells with intracytoplasmic phosphotungstic acid-hematoxylin-positive granules. The tumor cells stained positively for the CD3 antigen and negatively for a B-cell marker. A diagnosis of large granular lymphoma was based on the morphologic and immunohistochemical characteristics of the neoplasm. The postmortem presentation of this case depicted unusual multifocal, ulcerative lymphomatous lesions throughout the small intestine without involvement of the regional lymph nodes. The histologic and ultrastructural morphology of the neoplastic lymphocytes was similar to that in previously reported cases of abdominal equine large granular lymphomas, but in this case the neoplasm was restricted to the small intestine.
Pathogenesis of Experimental Vesicular Stomatitis Virus (New Jersey Serotype) Infection in the Deer Mouse (Peromyscus maniculatus)
Authors: Cornish T. E. , Stallknecht D. E. , Brown C. C. , Seal B. S. , Howerth E. W.
Published: April 2003

The pathogenesis of vesicular stomatitis virus (VSV) infection has not been investigated previously in native New World rodents that may have a role in the epidemiology of the disease. In the present study, 45 juvenile and 80 adult deer mice ( Peromyscus maniculatus) were inoculated intranasally with VSV New Jersey serotype (VSV-NJ) and examined sequentially over a 7-day period. Virus was detected by means of immunohistochemistry and in situ hybridization in all tissues containing histologic lesions. Viral antigen and mRNA were observed initially in olfactory epithelium neurons, followed by olfactory bulbs and more caudal olfactory pathways in the brain. Virus also was detected throughout the ventricular system in the brain and central canal of the spinal cord. These results support both viral retrograde transneuronal transport and viral spread within the ventricular system. Other tissues containing viral antigen included airway epithelium and macrophages in the lungs, cardiac myocytes, and macrophages in cervical lymph nodes. In a second experiment, 15 adult, 20 juvenile, and 16 nestling deer mice were inoculated intradermally with VSV-NJ. Adults were refractory to infection by this route; however, nestlings and juveniles developed disseminated central nervous system infections. Viral antigen also was detected in cardiac myocytes and lymph node macrophages in these animals. Viremia was detected by virus isolation in 35/72 (49%) intranasally inoculated juvenile and adult mice and in 17/36 (47%) intradermally inoculated nestlings and juveniles from day 1 to day 3 postinoculation. The documentation of viremia in these animals suggests that they may have a role in the epidemiology of vectorborne vesicular stomatitis.
Clinical, Pathologic, Immunohistochemical, and Virologic Findings of Eastern Equine Encephalomyelitis in Two Horses
Authors: Del Piero F. , Wilkins P. A. , Dubovi E. J. , Biolatti B. , Cantile C.
Published: April 2003

Natural eastern equine encephalitis alphavirus (EEEV) infection was diagnosed in two adult horses with anorexia and colic, changes in sensorium, hyperexcitability, and terminal severe depression. Myocardium, tunica muscularis of stomach, intestine, urinary bladder, and spleen capsule had coagulative necrosis and perivascular lymphocytic infiltrate. Central nervous system (CNS) lesions were diffuse polioencephalomyelitis with leptomeningitis characterized by perivascular T lymphocyte cuffing, marked gliosis, neuronophagia, and multifocal microabscesses. Lesions were more prominent within cerebral cortex, thalamus, hypothalamus, and mesencephalon. EEEV was identified in the cytoplasm of cardiac myocytes and smooth muscle cells of spleen, stomach, intestine, urinary bladder, blood vessels, and dendritic cells. In the CNS, EEEV-positive cells included neurons, astrocytes, oligodendrocytes, microglia, and neutrophils. EEEV was isolated from the CNS of both horses. The detailed description of the encephalic and spinal EEEV localization and the findings of EEEV in extraneural tissues contribute to the understanding of this important multisystemic zoonotic disease.
Morbilliviral Dermatitis in Seals
Authors: Lipscomb T. P. , Mense M. G. , Habecker P. L. , Taubenberger J. K. , Schoelkopf R.
Published: April 2003

A juvenile female hooded seal ( Cystophora cristata) and a juvenile male harp seal ( Phoca groenlandica) stranded separately on the New Jersey (USA) coast and were taken to a marine mammal rehabilitation center. Both were lethargic and emaciated, had dermatitis, and died. Histologic skin lesions in the seals were similar and consisted of epidermal and follicular epithelial hyperplasia, hyperkeratosis, degeneration, and necrosis. The most distinctive finding was extensive syncytial zones bounded superficially by hyperkeratosis and deeply by hyperplastic basal cells. Eosinophilic intracytoplasmic inclusion bodies were present in epithelial cells. Morbilliviral antigen was demonstrated in the skin lesions by immunohistochemistry. Phocine distemper virus was detected in the skin by reverse transcription polymerase chain reaction and a phocine distemper virus-specific probe using the Southern blot technique. This is the first report of morbilliviral dermatitis in marine mammals.
Hepatobiliary Inflammation, Neoplasia, and Argyrophilic Bacteria in a Ferret Colony
Authors: Garcí A. , Erdman S. E. , Xu S. , Feng Y. , Rogers A. B. , Schrenzel M. D. , Murphy J. C. , Fox J. G.
Published: April 2003

Hepatobiliary disease was diagnosed in eight of 34 genetically unrelated cohabitating pet ferrets ( Mustela putorios furo) during a 7-year period. The eight ferrets ranged in age from 5 to 8 years and exhibited chronic cholangiohepatitis coupled with cellular proliferation ranging from hyperplasia to frank neoplasia. Spiral- shaped argyrophilic bacteria were demonstrated in livers of three ferrets, including two with carcinoma. Sequence analysis of a 400-base pair polymerase chain reaction product amplified from DNA derived from fecal bacteria from one ferret demonstrated 98% and 97% similarity to Helicobacter cholecystus and Helicobacter sp. strain 266-11, respectively. The clustering of severe hepatic disease in these cohabitating ferrets suggests a possible infectious etiology. The role of Helicobacter species and other bacteria in hepatitis and/or neoplasia in ferrets requires further study.
Immunolocalization of the Smooth Muscle-Specific Protein Calponin in Complex and Mixed Tumors of the Mammary Gland of the Dog: Assessment of the Morphogenetic Role of the Myoepithelium
Authors: Espinosa de los Monteros A. , Millán M. Y. , Ordás J. , Carrasco L. , Reymundo C. , Martín de las Mulas J.
Published: April 2003

The immunohistochemical expression of the smooth muscle-specific protein calponin was studied to assess the contribution of myoepithelial cells to the histogenesis of spindle cells of complex and mixed tumors of the mammary gland of the dog and the origin of cartilage and bone in mixed tumors. Formalin-fixed tissues from 55 benign and malignant tumors (49 also containing surrounding normal mammary gland) were evaluated. Periacinar and periductal myoepithelial cells of all the 49 normal mammary glands were diffusely stained by the anti-human calponin monoclonal antibody. Calponin was found in 53 (98%) of the tumors studied, reacting with the myoepithelium-like cells of 86% of benign tumors and their remnants in 85% of malignant tumors. Five different types of calponin-immunoreactive myoepithelial cells were identified: hypertrophic myoepithelial cells, fusiform cells, stellate myoepithelial cells, rounded (myoepithelial) cells, and chondroblasts. Differences in staining intensity and staining pattern among these five types of cells suggested a transition of myoepithelial cells to chondroblasts. Stromal myofibroblasts also showed calponin immunoreactivity, but they did not react with a cytokeratin 14 monoclonal antibody, which recognizes myoepithelial cells in mammary gland. Calponin appears to be a very sensitive marker of normal and neoplastic myoepithelium in the canine mammary gland, and its identification in different cell types of complex and mixed tumors of the mammary gland of the dog suggests a major histogenetic role for myoepithelial cells.
Opioid Prescribing Patterns After Imposition of Setting-Specific Limits on Prescription Duration
Authors: Allen Lindsay D. , Pollini Robin A. , Vaglienti Richard , Powell David
Published: January 2024

Importance

Despite their widespread adoption across the US, policies imposing one-size-fits-all limits on the duration of prescriptions for opioids have shown modest and mixed implications for prescribing.

Objective

To assess whether a prescription duration limit policy tailored to different clinical settings was associated with shorter opioid prescription lengths.

Design, Setting, and Participants

This cross-sectional study examined changes in opioid prescribing patterns for opioid-naive Medicaid enrollees aged 12 to 64 years before and after implementation of a statewide prescription duration limit policy in West Virginia in June 2018. Patients with cancer or Medicare coverage were excluded. The policy assigned a 7-day duration limit to opioid prescriptions for adults treated in outpatient hospital- or office-based practices, a 4-day limit for adults treated in emergency departments, and a 3-day limit for pediatric patients younger than 18 years regardless of clinical setting. Data were examined from January 1, 2017, through September 30, 2019, and data were analyzed from June 12 to October 30, 2023.

Main Outcomes and Measures

Whether a patient’s initial opioid prescription was longer in days than the June 2018 policy limit for a given care setting before and after policy implementation. Interrupted time series models were used to calculate the association between the policy’s implementation and outcomes.

Results

The analytic sample included 44 703 Medicaid enrollees (27 957 patients [62.5%] before policy implementation and 16 746 patients [37.5%] after policy implementation; mean [SD] age, 33.9 [13.4] years; 27 461 females [61.4%]). Among adults treated in outpatient hospital- or office-based settings, the duration limit policy was associated with a decrease of 8.83 (95% CI, −10.43 to −7.23) percentage points (P < .001), or a 56.8% relative reduction, in the proportion of prescriptions exceeding the 7-day limit. In the emergency department setting, the policy was associated with a decrease of 7.03 (95% CI, −10.38 to −3.68) percentage points (P < .001), a 37.5% relative reduction, in the proportion of prescriptions exceeding the 4-day limit. The proportion of pediatric opioid prescriptions longer than the 3-day limit decreased by 12.80 (95% CI, −17.31 to −8.37) percentage points (P < .001), a 26.5% relative reduction, after the policy’s implementation.

Conclusions and Relevance

Results of this cross-sectional study suggest that opioid prescription duration limits tailored to different clinical settings are associated with reduced length of prescriptions for opioid-naive patients. Additional research is needed to evaluate whether these limits are associated with reductions in the incidence of opioid use disorder or with unintended consequences, such as shifts to illicit opioids.