bluuebunny/crossref_metadata_2025 huggingface dataset:
Pleural complications of pulmonary hydatid disease
Authors: Ozvaran Mustafa Kursat , Ersoy Yesim , Uskul Bahadir , Unver Ethem , Yalcin Engin , Baran Reha , Morice Rodolfo C.
Published: February 2004

Objective:  The aim of this study was to determine the incidence and diagnostic features of pleural manifestations of pulmonary hydatid disease.

Methodology:  Patients with pleural pathology in association with surgery for pulmonary hydatid disease over an 8‐year period were evaluated.

Results:  Twenty‐nine (6%) of 474 patients with histologically confirmed pulmonary hydatid disease had pleural abnormalities. The diagnosis was determined preoperatively in 22 patients and was based on radiographic, clinical, and/or serology findings. Bronchoscopic specimens were diagnostic in two of seven patients who had bronchoscopy. Five patients were not diagnosed until surgery. Radiographic abnormalities consisted of pleural thickening and/or free fluid without intrapleural rupture of the cysts in 21 patients. Eight patients had a hydropneumothorax. Sixteen patients had an exudative, uncomplicated effusion. The remaining patients had empyemas. All patients had resection of the pulmonary cysts, and 20 also underwent a pleurectomy. The mean length of hospital stay was 23 ± 14 days. There was no hospital mortality.

Conclusion:  Pleural lesions associated with pulmonary hydatid disease are rare and have a variable radiographic appearance. In regions in which echinococcal disease is endemic, a high level of clinical suspicion is necessary for diagnosis and appropriate management of this condition.
Incidence of community‐acquired pneumonia in children caused by Mycoplasma pneumoniae: Serological results of a prospective, population‐based study in primary health care
Authors: Korppi Matti , Heiskanen‐Kosma Tarja , Kleemola Marjaana
Published: February 2004

Objective:  The objective of the present study was to assess the incidence of community‐acquired pneumonia (CAP) in children caused by Mycoplasma pneumoniae.

Methodology:  During 12 months in 1981–1982, all CAP cases in a defined child population were registered. M. pneumoniae aetiology, initially measured by complement fixation (CF) test, was in 1999 supplemented by measurement of IgG and IgM antibodies using enzyme immunoassays (EIA).

Results:  M. pneumoniae was detected in 61 (30%) of 201 paediatric CAP cases, being the most common aetiological agent in those 5 years of age or over. At that age, M. pneumoniae was responsible for over 50% of cases, and over 90% of mycoplasmal cases were treated as outpatients. The EIA detected 17 new cases over and above the 44 detected by CF, while CF alone revealed 10 cases. The incidence of M. pneumoniae CAP increased with age, being over 10/1000 children at the age of 10 years or more. Co‐infections with Streptococcus pneumoniae and Chlamydia pneumoniae were present in over 30% and 15%, respectively, of mycoplasmal CAP cases.

Conclusion:  M. pneumoniae is a common cause of paediatric CAP in primary health care, and co‐infections with S. pneumoniae are common. Both S. pneumoniae and M. pneumoniae should be taken into account when starting antibiotics for children with CAP.
The influence of dexamethasone on the proliferation and apoptosis of pulmonary inflammatory cells in bleomycin‐induced pulmonary fibrosis in rats
Authors: Li Hui‐ping , Li Xia , He Guo‐jun , Yi Xiang‐hua , Kaplan Allen P.
Published: February 2004

Objective:  The aim of this study was to investigate the inhibitory effect of dexamethasone on the state of proliferation/apoptosis of the pulmonary inflammatory cells in a rat pulmonary fibrosis model induced by bleomycin.

Methodology:  Seventy‐five pathogen‐free Sprague‐Dawley (SD) rats were randomly divided into three groups: control, bleomycin (BLM) and dexamethasone (DXM) groups with 25 rats in each group. Each group was then divided into five subgroups based on time of study (1‐, 3‐, 7‐, 14‐ and 28‐days). BAL fluid was obtained, the cells were counted and a differential was performed. A lower DNA content in apoptotic cells was detected and quantitated by flow cytometry. Haematoxylin and eosin staining was performed to observe the extent of alveolitis and fibrosis of lung tissue; the morphological changes in apoptotic cells were discerned by transmission electron‐microscopy and a semi‐quantitative assessment of apoptotic cells in lung tissue was performed using in situ TUNEL (terminal deoxynucleotidyl transferase‐mediated dUTP nick endlabelling).

Results:  The total number of inflammatory cells and the percentage of neutrophils in BAL fluid in almost every subgroup of the DXM group were significantly lower than those in corresponding subgroups of the BLM group (P < 0.01). The percentages of apoptotic cells in BAL fluid in the 14‐day and 28‐day subgroups of the DXM group were higher than those in corresponding subgroups of the BLM group (P < 0.05). The peak of alveolitis in the DXM group shifted backward and the extent of fibrosis was less than that in the BLM group. The apoptosis index (AI) of inflammatory cells in each of the DXM subgroups was higher than that in corresponding BLM subgroups except for day 14.

Conclusion:  Dexamethasone can induce apoptosis of pulmonary inflammatory cells and reduce the extent of alveolitis and fibrosis in bleomycin‐induced pulmonary fibrosis of rats.
Intracellular glutathione in stretch‐induced cytokine release from alveolar type‐2 like cells
Authors: Jafari Behrouz , Ouyang Bin , Li Li‐Fu , Hales Charles A. , Quinn Deborah A.
Published: February 2004

Objective:  Ventilator‐induced lung injury (VILI) is characterized by release of inflammatory cytokines, but the mechanisms are not well understood. We hypothesized that stretch‐induced cytokine production is dependent on oxidant release and is regulated by intracellular glutathione (GSH) inhibition of nuclear factor κB (NF‐κB) and activator protein‐1 (AP‐1) binding.

Methodology:  Type 2‐like alveolar epithelial cells (A549) were exposed to cyclic stretch at 15% strain for 4 h at 20 cycles/min with or without N‐acetylcysteine (NAC) or glutathione monoethylester (GSH‐e) to increase intracellular GSH, or buthionine sulfoximine (BSO), to deplete intracellular GSH.

Results:  Cyclic stretch initially caused a decline in intracellular GSH and a rise in the levels of isoprostane, a marker of oxidant injury. This was followed by a significant increase in intracellular GSH and a decrease in isoprostane. Stretch‐induced IL‐8 and IL‐6 production were significantly inhibited when intracellular GSH was further increased by NAC or GSH‐e (P < 0.0001). Stretch‐induced IL‐8 and IL‐6 production were augmented when intracellular GSH was depleted by BSO (P < 0.0001). NAC blocked stretch‐induced NF‐κB and AP‐1 binding and inhibited IL‐8 mRNA expression.

Conclusions:  We conclude that oxidant release may play a role in lung cell stretch‐induced cytokine release, and antioxidants, which increase intracellular GSH, may protect lung cells against stretch‐induced injury.
Trace elements as a component of oxidative stress in COPD
Authors: Karadag Fisun , Cildag Orhan , Altinisik Mustafa , Kozaci Leyla D. , Kiter Goksel , Altun Cagatay
Published: February 2004

Objective:  The purpose of this study was to assess the serum concentrations of those trace elements that act as a component of oxidative stress in COPD patients. Clinically stable COPD outpatients (n = 26) and healthy controls (n = 24) were studied.

Methodology:  Serum concentrations of copper (Cu) and zinc (Zn) were determined using a Varian Spectra AA220 flame atomic absorption spectrophotometer. Serum concentration of iron (Fe) was measured by the ferene assay, using a commercially available kit (IL TestTM Iron) with the ILAbTM 900 autoanalyser. The lipid peroxidation product malondialdehyde (MDA) in serum samples was measured spectrophotometrically in terms of TBARS (thiobarbituric acid reactive substances).

Results:  The serum MDA concentration in COPD patients was found to be similar to the control group (0.68 ± 0.15 nmol/mL vs 0.62 ± 0.13 nmol/mL, respectively; P= 0.163). The serum concentrations of the trace elements in both study groups were in the normal reference range. There was no difference in Fe concentration between COPD patients and the control group (0.81 ± 0.38 µg/mL vs 0.92 ± 0.41 µg/mL; P= 0.360). Copper concentrations were higher (1.06 ± 0.26 µg/mL vs 0.92 ± 0.19 µg/mL; P <0.040); while zinc was lower in the COPD group compared to the controls (0.83 ± 0.25 µg/mL vs 1.03 ± 0.23 µg/mL; P= 0.006). Serum Zn concentrations were lower in the severe COPD patients compared to mild‐moderate COPD patients (P = 0.038).

Conclusion:  The results of this study indicate that there are alterations in serum concentrations of trace elements in COPD patients, suggesting that they may play a role in the pathophysiology of this disease by virtue of their role in oxidative stress. We recommend further studies on the role of trace elements in the pathophysiology of COPD, their association with markers of oxidant/antioxidant status and on the clinical significance of their deficiency.
Site fidelity in temporally correlated environments enhances population persistence
Authors: Schmidt Kenneth A.
Published: February 2004

Site fidelity, the phenomenon of remaining faithful to sites, often where an individual has bred successfully in the past, has important consequences for population dynamics. Previous results have shown that site fidelity results in a positive correlation between population density and fitness. Here, I build on this theme by incorporating site fidelity using the win‐stay : lose‐switch rule often seen among birds, i.e. individuals return to sites were they bred successfully in the past and vacate those where they have not. Results demonstrate that the combination of site fidelity and temporal autocorrelation in site quality can enhance the persistence of population networks, whereas either factor acting alone has little or no influence. Moreover, there is an abrupt threshold at moderate levels of temporal autocorrelation,ρtime > 0.35–0.4, beyond which persistence time and the probability of surviving >500 years is greatly accelerated. These results suggest that temporal autocorrelation combined with appropriate behavioural responses may enhance population persistence.
Consumer effects decline with prey diversity
Authors: Hillebrand Helmut , Cardinale Bradley J.
Published: February 2004

While consumer species diversity is known to influence the capture of limited resources, little is known about how prey diversity impacts the transfer of energy and matter among trophic levels. Here, we perform a meta‐analysis of experiments that have examined the impact of grazers on the biomass of periphytic algae to test the hypothesis that the magnitude of consumer (grazer) effects on prey (algae) depends on the species diversity of the prey assemblage. The analysis reveals that consumer effects tend to decrease as the diversity of a prey assemblage increases. This trend is robust for several different, yet complementary indices of grazer effect size and algal diversity. The trend also remains significant after statistically controlling for a variety of factors that can covary with prey diversity among studies. We discuss several possible mechanisms for the documented pattern, such as diversity enhancing the probability of inedibility and of positive interactions.
A novel genealogical approach to neutral biodiversity theory
Authors: Etienne Rampal S. , Olff Han
Published: February 2004

Current neutral theory in community ecology views local biodiversity as a result of the interplay between speciation, extinction and immigration. Simulations and a mean‐field approximation have been used to study this neutral theory. As simulations have limitations of convergence and the mean‐field approximation ignores dependencies between species’ abundances when applied to species‐abundance data, there is still no final conclusion whether the neutral theory or the traditional lognormal model describes community structure best. We present a novel analytical framework, based on the genealogy of individuals in the local community, to overcome the problems of previous approaches, and show, using Bayesian statistics, that the lognormal model provides a slightly better fit to the species‐abundance distribution of a much‐discussed tropical tree community. A key feature of our approach is that it shows the tight link between genetic and species diversity, which creates important perspectives to future integration of evolutionary and community ecological theory.
Quantifying the effects of fisheries on threatened species: the impact of pelagic longlines on loggerhead and leatherback sea turtles
Authors: Lewison Rebecca L. , Freeman Sloan A. , Crowder Larry B.
Published: February 2004

The depletion of fish stocks from global fisheries has been a long‐standing concern. More recently, incidental catch of non‐target (termed bycatch) vertebrates also has been proposed as a serious conservation issue. Here we present a bycatch assessment for loggerhead and leatherback sea turtles that are incidentally caught by global pelagic longlines. We integrate catch data from over 40 nations and bycatch data from 13 international observer programmes. Despite infrequent rates of encounter, our analyses show that more than 200 000 loggerheads and 50 000 leatherbacks were likely taken as pelagic longline bycatch in 2000. Our analyses suggest that thousands of these turtles die each year from longline gear in the Pacific Ocean alone. Given 80–95% declines for Pacific loggerhead and leatherback populations over the last 20 years, this bycatch level is not sustainable. Adopting a large‐scale, synthetic approach is critical to accurately characterize the influence of global fisheries bycatch on globally distributed and imperilled pelagic vertebrates.
Use of forward versus backward reasoning during audit analytical procedures: evidence from a computerised‐process‐tracing field study
Authors: O'Donnell Ed
Published: February 2004

Audit judgement research has widely assumed that auditors rely primarily on backward reasoning during analytical procedures but the relative use of forward reasoning has not been directly examined. The present study explains how auditors use backward and forward reasoning during analytical procedures, discusses evidence from other research suggesting that forward reasoning could be more prevalent, and examines the relative use of forward reasoning during analytical procedures with data from a computerised process‐tracing field study. Results suggest that auditors rely extensively on forward reasoning when using analytical procedures. Findings motivate future research that examines when forward and backward reasoning are most effective.
Impact of intelligent decision aids on expert and novice decision‐makers’ judgments
Authors: Arnold Vicky , Collier Philip A. , Leech Stewart A. , Sutton Steve G.
Published: February 2004

Businesses have invested tremendous resources into intelligent decision aid development. A good match between user and aid may improve the expert decision‐maker's decision quality. However, novices may be prone to poorer decision‐making if intelligent decision aids are more expert than the user. The present paper provides an empirical test of the impact of decision aids on subjects with differential expertise levels. The results support the contention that intelligent decision aids aggravate bias in novices’ decision‐making but mitigate bias in experts’ decision‐making processes. Intelligent decision aids may be best viewed as complements to expert decision‐makers during complex problem analysis and resolution.
Stock preferences and derivative activities of Australian fund managers
Authors: Pinnuck Matt
Published: February 2004

The present paper examines both the characteristics of stocks that fund managers prefer to hold and their use of derivatives. We find strong evidence that fund managers prefer large, liquid and low volatility stocks. Weak evidence exists that fund managers prefer to hold stocks that are past winners. In relation to derivatives, just over half of the sampled Australian fund managers hold derivatives in the form of exchange traded options. Of those that do trade in derivatives, it is found the level of exposure to stock price movements achieved by options is not significant relative to the total investment portfolio.
Annotation: The similarities and differences between autistic disorder and Asperger's disorder: a review of the empirical evidence
Authors: Macintosh Kathleen E. , Dissanayake Cheryl
Published: February 2004

Background: The ongoing controversy over the distinction between autistic disorder and Asperger's disorder is important to resolve because of the implications regarding an understanding of the aetiology and prognosis, and the diagnostic and clinical practices relating to these conditions. This paper provides a critical evaluation of current published research evidence.

Method: Databases, such as PsychINFO and Medline, as well as book chapters, reference lists from relevant articles, and recent editions of key journals were searched for all relevant studies (until 2002) which incorporated participants diagnosed with high‐functioning autism and Asperger's disorder using either cluster analysis or comparative approaches to examine similarities and differences between these groups. Keywords used in the searches included autistic disorder, Asperger's disorder, autism, high‐functioning autism, and pervasive developmental disorder.

Results: On the basis of the available evidence, there seem to be few qualitative differences between autistic disorder and Asperger's disorder.

Conclusion: There is currently insufficient evidence to establish the validity of Asperger's disorder as a syndrome distinct from high‐functioning autism. The findings are consistent with the view that these disorders belong on an autism spectrum.
Attention orienting by another's gaze direction in children with autism
Authors: Kylliäinen Anneli , Hietanen Jari K.
Published: February 2004

Background:  The aim of this study was to investigate attention orienting triggered by another's gaze direction in autism.

Method:  Twelve high‐functioning children with autism and gender‐ and age‐matched normal control children were studied using two tasks. In the first task, children were asked to detect laterally presented target stimuli preceded by centrally presented facial cue stimuli in which gaze was either straight ahead or averted. The direction of the cue was either congruent, neutral, or incongruent with respect to the laterality of the target stimulus. In the second task, children were asked to discriminate the direction of eye gaze.

Results:  The results showed that another person's static gaze direction triggered an automatic shift of visual attention, both in children with autism and in normally developing children. The children in both groups were also able to overtly discriminate the direction of the gaze.

Conclusion:  These results seem to suggest that, in children with autism, the visual system processes information about another person's gaze direction and sends this information to those areas that subserve reflexive attention orienting. However, future studies are needed to investigate whether the processing of eyes and gaze direction relies on similar neural mechanisms in children with autism and in normally developing children.
Gestalt processing in autism: failure to process perceptual relationships and the implications for contextual understanding
Authors: Brosnan Mark J. , Scott Fiona J. , Fox Simone , Pye Jackie
Published: February 2004

Background:  Deficits in autism have been characterised as a bias towards local over global processing. This paper examines whether there is a deficit in gestalt grouping in autism.

Method:  Twenty‐five low‐functioning children with autism and 25 controls who were matched for chronological age and verbal mental age took part in the study.

Results:  The autism group utilised gestalt grouping principles (proximity, similarity, closure) significantly less than the controls. Calculating an overall index of gestalt grouping, the autism group performed at chance level. There was also a deficit in identifying certain impossible figures. This pattern was not reflected in a drawing task, in which the autism sample conformed more to gestalt grouping principles than controls (non‐significantly).

Conclusions:  The results are discussed in terms of a failure in autism to process inter‐element relationships that would allow for the appreciation of larger perceptually coherent units that comprise of multiple elements and, consequently, context. The processes are argued to be preattentive.
A developmental analysis of self‐reported fears in late childhood through mid‐adolescence: social‐evaluative fears on the rise?
Authors: Michiel Westenberg P. , Drewes Martine J. , Goedhart Arnold W. , Siebelink Berend M. , Treffers Philip D.A.
Published: February 2004

Background:  The frequently reported decline in the overall frequency and intensity of fears during late childhood and adolescence may mask different developmental patterns for two broad subclasses of fears: fears concerning physical danger and fears concerning social evaluation. It was investigated if physical fears decrease between late childhood and mid‐adolescence, while social‐evaluative fears increase during this period. It was also studied if changes in both sets of fears are more strongly related to socio‐cognitive maturity than to age, which itself is only a proxy measure of maturity.

Methods:  A non‐clinical sample of 882 children and adolescents (ages 8–18) was recruited for study. Fears were assessed using the Ollendick Fear Survey Schedule for Children – Revised (FSSC‐R). A Principal Components Analysis (PCA) was conducted to study the factor structure of the Failure and Criticism subscale of the FSSC‐R. Level of development was assessed using the Sentence Completion Test for Youth (SCT‐Y), a measure of socio‐cognitive maturity that is based on Loevinger's model, and measure, of ego development.

Results:  The PCA of the Failure and Criticism subscale revealed three factors: Social Evaluation, Achievement Evaluation, and Punishment. As predicted, the significant decrease of overall fearfulness obscured two contradictory developmental patterns: (a) fears of physical danger and punishment decreased with age, whereas (b) fears of social and achievement evaluation increased with age. Hierarchical regression analyses showed that the age effect for social‐evaluative fears was explained entirely on the basis of developmental differences in socio‐cognitive maturity (controlling for verbal ability). In contrast, age was a better predictor of the decrease of physical and punishment fears (although socio‐cognitive maturity still added to the predictive value of age).

Conclusion:  The expression of social evaluation fears during adolescence appears not atypical and might be a corollary of socio‐cognitive maturation. At the same time, the natural presence of those fears during adolescence appears to constitute a vulnerability for developing a social anxiety disorder.
A genetic analysis of individual differences in dissociative behaviors in childhood and adolescence
Authors: Becker‐Blease Kathryn A. , Deater‐Deckard Kirby , Eley Thalia , Freyd Jennifer J. , Stevenson Jim , Plomin Robert
Published: February 2004

Background:  Dissociation – a pattern of general disruption in memory and consciousness – has been found to be an important cognitive component of children's and adults’ coping with severe trauma. Dissociative experiences include amnesia, identity disturbance, age regression, difficulty with concentration, and trance states. Stable individual differences in dissociative behaviors may represent a dissociative tendency trait that varies in the population independent of the influence of trauma.

Method:  In the current study, we examined genetic and environmental sources of variance in some of these behaviors by comparing 86 pairs of adoptive siblings and 102 pairs of full siblings from the Colorado Adoption Project (parents’ and teachers’ ratings), and 218 pairs of identical and 173 pairs of same‐sex fraternal twins from the British Register for Child Twins (parents’ ratings). The study used a dissociation scale comprised of six CBCL items.

Results:  Developmentally, there was no change in mean dissociation scores across middle childhood and adolescence, and individual differences were moderately stable. Both parents’ and teachers’ ratings showed moderate to substantial amounts of genetic and nonshared environmental variance and negligible shared environmental variance, and most of the parent–teacher agreement in their ratings was accounted for by overlapping genetic variance.

Conclusions:  The results support further research into possible genetic and environmental factors that contribute to dissociative tendencies in children and adolescents.
Conduct Disorder and Oppositional Defiant Disorder in a national sample: developmental epidemiology
Authors: Maughan Barbara , Rowe Richard , Messer Julie , Goodman Robert , Meltzer Howard
Published: February 2004

Background: Despite an expanding epidemiological evidence base, uncertainties remain over key aspects of the epidemiology of the ‘antisocial’ disorders in childhood and adolescence.

Methods: We used cross‐sectional data on a nationally representative sample of 10,438 5–15‐year‐olds drawn from the 1999 British Child Mental Health Survey to examine age trends, gender ratios and patterns of comorbidity in DSM‐IV Conduct Disorder (CD) and Oppositional Defiant Disorder (ODD).

Results: CD was significantly more common in boys than girls, and increased in prevalence with age. Among children who met diagnostic criteria for CD, status violations and other non‐aggressive conduct problems increased with age, while aggressive symptoms became less common. Gender differences in ODD varied by reporter. Estimates of age trends in ODD depended heavily on treatment of overlaps with CD. Following DSM‐IV guidelines (where ODD is not diagnosed in the presence of CD), rates of ODD fell with age; if that constraint was released, clinically significant rates of oppositionality persisted at similar levels from early childhood to middle adolescence. CD and ODD showed high levels of overlap, and both diagnoses showed substantial comorbidity with other non‐antisocial disorders.

Conclusions: Results from this large‐scale study confirm and extend previous findings in the epidemiology of the disruptive behaviour disorders.
To what extent is failure to thrive in infancy associated with poorer cognitive development? A review and meta‐analysis
Authors: Corbett S.S. , Drewett R.F.
Published: February 2004

Background:  Previous empirical studies of the cognitive sequelae of failure to thrive in infancy have led to apparently inconsistent conclusions.

Methods:  Studies of cognitive abilities in failure to thrive were located through published bibliographies, supplemented by a search through MEDLINE. They were classified (a) into those in which the cases were identified in hospital or other specialist clinics, and those in which they were identified in primary care or by whole population screening; (b) into those that were controlled and those that were not controlled; and (c) into those with a cross‐sectional and those with a longitudinal design. Effect sizes in controlled studies were summarised using D statistics for the principal cognitive outcome measure, from the last occasion on which the child was tested if the study was longitudinal.

Results:  In studies with cases identified in hospital or other specialist clinics (52 cases, 36 controls), the pooled effect size (weighted standardised mean difference) for cognitive outcomes was −.85 (95% CI −.41 to −1.30). In studies with cases identified in primary care (552 cases, 573 controls), it was −.30 (95% CI −.18 to −.42). In each longitudinal study testing the same children at different ages, the effect size was smaller when the children were older. To obtain an overall estimate of the long‐term cognitive outcome of failure to thrive in infancy, data from controlled studies in which cases were identified in primary care, and restricted to IQ or McCarthy scale scores in older children (502 cases, 523 controls), were used. The weighted mean difference was −.28 (95% CI −.16 to −.41), equivalent to 4.2 IQ points (95% CI 2 to 6).

Conclusions:  Evidence from reasonably well‐controlled studies indicates that failure to thrive in infancy is associated with adverse intellectual outcomes sufficiently large to be of importance at a population level.
Treatment of Septic Common Digital Extensor Tenosynovitis by Complete Resection in Seven Horses
Authors: Booth Todd M. , Abbot John , Clements Antony , Singer Ellen R. , Clegg Peter D.
Published: February 2004

Objective—To describe and evaluate a technique for radical resection of the entire intrathecal component of the common digital extensor tendon (CDET) in horses.

Study Design—Prospective clinical study.

Animals or Sample Population—Seven client‐owned horses.

Methods—Seven horses with wounds that resulted in septic tenosynovitis of the CDET sheath were treated by complete surgical resection of the affected tendon and ablation of the tendon sheath; 5 had previous surgery that was unsuccessful. Time from initial injury to complete resection was 1–22 weeks. In 6 horses, the wound was closed primarily using a closed suction (4 horses), penrose (1), or passive open drainage system (1). In 1 horse, the surgical wound healed by second intention. All horses had postoperative bandaging, antibiotic administration, and physiotherapy.

Results—Surgical wounds healed primarily in 6 horses and by second intention in 1 horse. Follow‐up (mean, 26.4 months; range, 18–38 months) was available for 6 horses; all returned to their athletic performance level without lameness or gait abnormality.

Conclusions—Complete resection of the CDET was an effective surgical technique for management of chronic septic tenosynovitis.

Clinical Relevance—Horses with infection of the CDET and its sheath may be returned to long‐term soundness without gait abnormality after radical resection.
Treatment of Nonunions with Nonglycosylated Recombinant Human Bone Morphogenetic Protein‐2 Delivered from aFibrinMatrix
Authors: Schmökel Hugo G. , Weber Franz E. , Seiler Gabriela , Von Rechenberg Brigitte , Schense Jason C. , Schawalder Peter , Hubbell Jeffrey
Published: February 2004

Objective— To report the results of the treatment of nonunions with nonglycosylated recombinant human bone morphogenetic protein‐2 (nglBMP‐2) delivered from a designed fibrin matrix.

Study Design— Experimental trial in rodents and prospective clinical study in dogs and cats with nonunion fractures.

Animals— Twenty adult female, albino, Sprague–Dawley rats; 8 client‐owned cats and dogs.

Methods— After development of a fibrin matrix and evaluation of nglBMP‐2 in a rodent femoral defect model, 8 consecutive long bone nonunion fractures (no progression in healing in ≥3 months), were treated using 300 μg nglBMP‐2 in a liquid fibrin precursor, injected into the defect gap after fracture revision and stabilization, or through a stab incision into the fracture site. The fibrin matrix was designed to clot in the wound after 60 seconds and to release the nglBMP‐2 continuously over several days.

Results— Using only fibrin gel, 7% of the rat femoral defect was filled with new formed bone compared with 79% defect filling using 2μg nglBMP‐2 (P=.006). Five and 10 μg nglBMP in fibrin resulted in union of all femoral defects with complete filling of the gap with new bone. Bony bridging and clinical healing was achieved in 7 patients within 24 weeks of administration of nglBMP‐2.

Conclusions— Application of nglBMP‐2 in a functional matrix can induce bone healing. Controlled release of nglBMP‐2 from a fibrin matrix mimics the natural fracture hematoma.

Clinical Relevance— nglBMP‐2/fibrin can successfully replace a cancellous bone autograft in fracture treatment with an associated reduction in graft donor site morbidity and surgical time.
The Three‐Loop Pulley Suture Versus Two Locking‐Loop Sutures for the Repair of Canine Achilles Tendons
Authors: Moores Andy P. , Owen Martin R. , Tarlton John F.
Published: February 2004

Objective— To compare a 3‐loop pulley suture pattern with 2 locking‐loop sutures for the repair of components of the canine Achilles mechanism.

Study Design— In vitro biomechanical study.

Animals— Forty‐eight paired tendons collected from 9 canine cadavers.

Methods— Paired tendons were repaired with either a 3‐loop pulley suture or 2 locking‐loop sutures and tensile tested to failure. To ensure accurate anastomosis gap measurement a direct, non‐contact, method of gap measurement, using digital video, was devised. Load initiating gap formation (defined as load at a 1 mm gap) and load producing a 3 mm gap were evaluated in addition to maximum load, gap at failure, mode of failure, and time spent placing the sutures.

Results— Maximum load values were similar for both repairs. The mean 1 mm gap loads were 44.0 and 18.4 N, and the mean 3 mm gap loads were 56.3 and 34.7 N, for the 3‐loop pulley pattern and the 2 locking‐loops, respectively; these differences were statistically significant. The 3‐loop pulley pattern was faster to place and resulted in a smaller gap at failure. All but 2 repairs failed by suture pull out.

Conclusions— The 3‐loop pulley pattern is more resistant to gap formation during tensile loading, and is quicker to place, than 2 locking‐loop sutures.

Clinical Relevance— Gap formation can significantly delay tendon healing. Tendon repairs with a gap >3 mm are reported to be at increased risk of rupture during the first 6 weeks postoperatively.
Miniplate Reconstruction of Severely Comminuted Maxillary Fractures in Two Dogs
Authors: Boudrieau Randy J.
Published: February 2004

Objective—To describe the treatment of severely comminuted maxillary fractures that resulted in separation of the maxilla from the base of the skull in 2 dogs. The structural areas of support, identified by thicker areas of bones of the skull, were used as a guide to apply buttress plate fixation, with miniplates using these apparent structural buttresses.

Study Design—Case report.

Sample Population—A 1‐year‐old Borzoi and a 5‐year‐old German shepherd dog.

Results—Fractures were repaired in a single procedure that resulted in excellent postoperative occlusion, immediate function, and cosmetic result. Healing was uneventful. Full function and excellent cosmetic appearance were still evident at 5 years, and the miniplates have not been removed.

Conclusions—Long‐term outcome appeared to justify surgical reconstruction of these severely comminuted fractures with miniplate methods similar to those used in human maxillofacial surgery. Miniplates were easily contoured 3‐dimensionally and placed along apparent lines of buttress support. Miniplate fixation provided a simple method to secure the bone fragments with excellent stability while maintaining both bony and soft tissue stability.

Clinical Relevance—Severely comminuted maxillary fractures in the dog may be repaired with miniplate fixation, using fixation principles identical to those used for similarly complex fractures in human maxillofacial surgery.
Intraosseous Gentamicin Perfusion of the Distal Metacarpus in Standing Horses
Authors: Mattson Shawn , Bouré Ludovic , Pearce Simon , Hurtig Mark , Burger John , Black William
Published: February 2004

Objective—To report tissue gentamicin concentrations after intraosseous (IO) perfusion in standing horses.

Study Design––In vivo study.

Animals or Sample Population––Twelve horses.

Methods—Sedated horses had a cannulated cortical bone screw inserted into the dorsolateral aspect of the treated metacarpus and a tourniquet applied proximally. Gentamicin (2.2 mg/kg) diluted in sterile saline solution (0.1 mL/kg) was infused through the screw. Two horses were euthanatized at each time interval: 0, 2, 6, 12, 24, and 36 hours. Synovial fluid and bone samples were collected distal to the screw from both forelimbs. Gentamicin concentrations were measured using fluorescence polarization immunoassay.

Results—The highest synovial fluid gentamicin concentrations were 385±273 μg/mL (mean±SD) in the metacarpophalangeal joint, 225±205 μg/mL in the proximal interphalangeal joint, 215±205 μg/mL in the distal interphalangeal joint, 382±195 μg/mL in the digital flexor tendon sheath, and 206±161 μg/mL in the navicular bursa. The highest bone concentrations of gentamicin were 55±30 μg/g in the distal metacarpus, 34±27 μg/g in the proximal, 16±15 μg/g in the middle, and 16±2.2 μg/g in the distal phalanges, and 27±17 μg/g in the proximal and 24±11 μg/g in the distal sesamoid bones.

Conclusion—Standing IO perfusion of gentamicin resulted in local antibiotic concentrations in the synovial structures and bones of the distal aspect of the limb that exceed the reported minimum inhibitory concentration of pathogens commonly implicated in equine orthopedic infections.

Clinical Relevance—Standing IO perfusion of gentamicin in the distal aspect of the limb should be considered for treatment of orthopedic infections of this region in horses.
Use of the Scrotum as a Transposition Flap for Closure of Surgical Wounds in Three Dogs
Authors: Matera Julia Maria , Tatarunas Angélica Cecília , Fantoni Denise Tabacchi , De Carvalho Vasconcellos Carmen Helena
Published: February 2004

Objective— To describe use of the scrotum as a pedicle flap to cover defects created by tumor excision in the perineum or caudal and medial aspect of the thigh.

Study Design— Clinical study.

Animals— Three dogs.

Methods— After tumor excision and prescrotal castration, an incision was made around the base of the scrotum, leaving a pedicle on the side opposite the skin defect. After removal of the tunica dartos and abdominal fascia, the scrotal skin was stretched and shaped to the defect, then sutured in position with a simple interrupted pattern. Bandages that were changed every 48 hours compressed the flaps, and healing was observed until sutures were removed.

Results— Two dogs had first intention healing in 15 days, whereas 1 dog developed necrosis of 10% of the flap, and this area healed by second intention.

Conclusion— In male dogs, the scrotal skin can be used as a pedicle flap for reconstructive surgery of wounds in the perineum and the proximomedial and caudal aspect of the thigh.

Clinical Relevance— The perineal region remains a surgical challenge because of the lack of the available skin for reconstruction of surgical wounds. The scrotal skin should be considered for use as a transposition flap to cover skin defects in this region.
Clenbuterol antagonizes glucocorticoid‐induced atrophy and fibre type transformation in mice
Authors: Pellegrino Maria Antonietta , D'Antona Giuseppe , Bortolotto Susan , Boschi Federica , Pastoris Ornella , Bottinelli Roberto , Polla Biagio , Reggiani Carlo
Published: February 2004

Beta‐agonists and glucocorticoids are frequently coprescribed for chronic asthma treatment. In this study the effects of 4 week treatment with beta‐agonist clenbuterol (CL) and glucocorticoid dexamethasone (DEX) on respiratory (diaphragm and parasternal) and limb (soleus and tibialis) muscles of the mouse were studied. Myosin heavy chain (MHC) distribution, fibres cross sectional area (CSA), glycolytic (phosphofructokinase, PFK; lactate dehydrogenase, LDH) and oxidative enzyme (citrate synthase, CS; cytochrome oxidase, COX) activities were determined. Muscle samples were obtained from four groups of adult C57/B16 mice: (1) Control (2) Mice receiving CL (CL, 1.5 mg kg−1 day−1 in drinking water) (3) Mice receiving DEX (DEX, 5.7 mg kg−1 day−1s.c.) (4) Mice receiving both treatments (DEX + CL). As a general rule, CL and DEX showed opposite effects on CSA, MHC distribution, glycolytic and mitochondrial enzyme activities: CL alone stimulated a slow‐to‐fast transition of MHCs, an increase of PFK and LDH and an increase of muscle weight and fibre CSA; DEX produced an opposite (fast‐to‐slow transition) change of MHC distribution, a decrease of muscle weight and fibre CSA and in some case an increase of CS. The response varied from muscle to muscle with mixed muscles, as soleus and diaphragm, being more responsive than fast muscles, as tibialis and parasternal. In combined treatments (DEX + CL), the changes induced by DEX or CL alone were generally minimized: in soleus, however, the effects of CL predominated over those of DEX, whereas in diaphragm DEX prevailed over CL. Taken together the results suggest that CL might counteract the unwanted effects on skeletal muscles of chronic treatment with glucocorticoids.
Retrograde transfer of steroid hormones to the ovary in luteal and follicular phases of porcine oestrous cycle in vivo
Authors: Stefańczyk‐Krzymowska S. , Wa̧sowska B. , Chłopek J. , Grzegorzewski W.
Published: February 2004

The efficiency of the retrograde transfer of steroid ovarian hormones from the ovarian effluent into blood supplying the ovary and the rate of its back transport to the ovary were determined for the first time in in vivo conditions. Sexually mature gilts (n= 25) were used in the physiological study. The concentration of oestradiol and progesterone in blood collected from the ovarian artery was higher in both the follicular phase (by 87.9 ± 2.9% and 150.0 ± 4.8%, respectively, P < 0.001) and the luteal phase (by 82.1 ± 3.9% and 77.7 ± 2.7%, respectively, P < 0.001) than in systemic blood reaching the initial part of the ovarian artery. The high efficiency of the retrograde transfer was not dependent on the concentration of hormones in the ovarian venous blood. However, the efficiency and rate of the retrograde transfer differed between phases of the oestrous cycle. We suggest that such effective retrograde transfer of ovarian hormones must affect the secretory function of the ovary.
Comparison of the firing patterns of human postganglionic sympathetic neurones and spinal α motoneurones during brief bursts
Authors: Macefield Vaughan G. , Elam Mikael
Published: February 2004

Focal recordings from individual postganglionic sympathetic neurones in awake human subjects have revealed common firing properties. One of the most striking features is that they tend to fire only once per sympathetic burst. Why this should be so is not known, but we propose that the short duration of the burst may limit the number of times a sympathetic neurone can fire. Indeed, while the normal variation in cardiac interval and burst duration is too narrow to reveal a correlation between burst duration and the number of spikes generated, we know that spike generation is doubled when burst duration is doubled following ectopic heart beats. To test the hypothesis that the burst duration constrains the firing of individual sympathetic neurones to one per burst, we used the human skeletomotor system as a model for the sympathetic nervous system, which allowed us to vary burst duration and amplitude experimentally. Intramuscular recordings were made from 27 single motor units (α motoneurones) in the tibialis anterior or soleus muscles of seven subjects; multiunit EMG activity was recorded via surface electrodes and blood pressure was recorded continuously. Subjects were instructed to generate EMG bursts of varying amplitude in the intervals between heart beats. By constraining the firing of α motoneurones to brief (∼400 ms) bursts we could emulate real sympathetic bursts. Individual motoneurones generated 0–7 spikes during the emulated sympathetic bursts, with firing patterns similar to those exhibited by real sympathetic neurones. Eleven motor units showed significant positive linear correlations between the number of spikes they generated within a burst and its amplitude, whereas for 17 motor units there were significant positive correlations between the number of spikes and burst duration. This indicates that burst duration is a major determinant of the number of times an α motoneurone will fire during a brief burst, and we suggest that the same principle may explain the firing pattern typical of human sympathetic neurones.
Interaction between direct sympathetic and vagus nerve stimulation on heart rate in the isolated rabbit heart
Authors: Brack Kieran E. , Coote John H. , Ng G André
Published: February 2004

The interaction between the effects of vagus nerve stimulation (VS) and sympathetic stimulation (SS) on intrinsic heart rate was studied in the novel innervated isolated rabbit heart preparation. The effects of background VS, at different frequencies – 2 Hz (low), 5 Hz (medium), 7 Hz (high) – on the chronotropic effects of different frequencies of SS – 2 Hz (low), 5 Hz (medium), 10 Hz (high) – were studied. The experiments were repeated in the reverse direction studying the effects of different levels of background SS on the chronotropic effects of different levels of VS. Background VS reduced the overall positive chronotropic effect of SS at steady state in a frequency dependent manner and the rate of increase in heart rate during low and medium SS (but not high SS) was slowed in the presence of background VS. These results suggest that pre‐ and postjunctional mechanisms may be involved in the sympatho–vagal interaction on heart rate. On the other hand, the chronotropic effect of VS was enhanced in the presence of background SS. Vagal stimulation appears to play a dominant role over sympathetic stimulation in chronotropic effects on the isolated heart. The innervated isolated heart preparation is a valuable model to study the complex mechanisms underlying the interaction between sympathetic and parasympathetic stimulation on cardiac function.
Effects of chronic intermittent asphyxia on haematocrit, pulmonary arterial pressure and skeletal muscle structure in rats
Authors: Bradford Aidan
Published: February 2004

Sleep‐disordered breathing in humans is a common condition associated with serious cardiovascular and other abnormalities. The prevalence and pathogenesis of increased haematocrit and pulmonary hypertension is controversial and it has been suggested that these changes only occur in patients who also have daytime continuous hypoxaemia. The hypothesis tested here is that the chronic intermittent hypoxia and asphyxia associated with sleep‐disordered breathing causes erythropoiesis and pulmonary hypertension and that this occurs in the absence of periods of continuous hypoxia. In humans and animals with obstructive sleep apnoea, there are abnormalities of upper airway muscle structure that have been ascribed to increased load placed on these muscles. An alternative hypothesis is that chronic intermittent hypoxia and asphyxia cause changes in upper airway muscle structure and function. To test these hypotheses, rats were exposed to intermittent hypoxia and asphyxia for 8 h per day for 5 weeks. This caused an increase in haematocrit, right ventricular weight and pulmonary arterial pressure. There were only slight changes in diaphragm, upper airway and limb muscle structure and force production but in general, muscle fatigability was increased. In conclusion chronic intermittent hypoxia and asphyxia cause an increase in haematocrit and pulmonary arterial pressure in the absence of periods of continuous hypoxia. Chronic intermittent hypoxia and asphyxia have little effect on skeletal muscle structure and force production but increase muscle fatigue. Increased upper airway muscle fatigue could lead to a vicious cycle of further compromise in upper airway patency and further hypoxia and asphyxia.