bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hypothalamic‐Pituitary‐Adrenal Axis Dysfunction in Hospitalized Neonatal Foals
Authors: Hart K.A. , Slovis N.M. , Barton M.H. 
Published: June 2009

Background:Transient hypothalamic‐pituitary‐adrenal (HPA) axis dysfunction occurs frequently in critically ill humans and impacts survival. The prevalence and impact of HPA axis dysfunction in critically ill neonatal foals are not well characterized.Hypotheses:(1) HPA axis dysfunction occurs in hospitalized neonatal foals, and is characterized by inappropriately low basal serum cortisol concentration or inadequate cortisol response to exogenous adrenocorticotropic hormone (ACTH); (2) hospitalized foals with HPA axis dysfunction have more severe disease and are less likely to survive than hospitalized foals with normal HPA axis function.Animals:Seventy‐two hospitalized foals and 23 healthy age‐matched foals.Methods:Basal ACTH and cortisol concentrations were measured and a paired low‐dose (10 μg)/high‐dose (100 μg) cosyntropin stimulation test was performed at admission in hospitalized foals. HPA axis dysfunction was defined as (1) an inappropriately low basal cortisol concentration or (2) an inadequate increase in cortisol concentration (delta cortisol) after administration of cosyntropin, with cut‐off values for appropriate basal and delta cortisol concentrations determined from results obtained in healthy age‐matched foals.Results:Forty‐six percent of hospitalized foals had an inappropriately low basal cortisol concentration and 52% had an inadequate delta cortisol concentration after administration of the 100 μg dose of cosyntropin. An inadequate delta cortisol response to the high (100 μg) dose of cosyntropin was significantly correlated with shock and multiple organ dysfunction syndrome in hospitalized foals, and with decreased survival in a subgroup of septic foals.Conclusions and Clinical Importance:HPA axis dysfunction occurs frequently in hospitalized neonatal foals, and negatively impacts disease severity and survival.
Effects of Body Positioning on Swallowing and Esophageal Transit in Healthy Dogs
Authors: Bonadio C.M. , Pollard R.E. , Dayton P.A. , Leonard C.D. , Marks S.L. 
Published: June 2009

Background: Contrast videofluoroscopy is the imaging technique of choice for evaluating dysphagic dogs. In people, body position alters the outcome of videofluoroscopic assessment of swallowing.Hypothesis/Objective: That esophageal transit in dogs, as measured by a barium esophagram, is not affected by body position.Animals: Healthy dogs (n= 15).Methods: Interventional, experimental study. A restraint device was built to facilitate imaging of dogs in sternal recumbancy. Each dog underwent videofluoroscopy during swallowing of liquid barium and barium‐soaked kibble in sternal and lateral recumbancy. Timing of swallowing, pharyngeal constriction ratio, esophageal transit time, and number of esophageal peristaltic waves were compared among body positions.Results: Transit time in the cervical esophagus (cm/s) was significantly delayed when dogs were in lateral recumbency for both liquid (2.58 ± 1.98 versus 7.23 ± 3.11; P= .001) and kibble (4.44 ± 2.02 versus 8.92 ± 4.80; P= .002). In lateral recumbency, 52 ± 22% of liquid and 73 ± 23% of kibble swallows stimulated primary esophageal peristalsis. In sternal recumbency, 77 ± 24% of liquid (P= .01 versus lateral) and 89 ± 16% of kibble (P= .01 versus lateral) swallows stimulated primary esophageal peristalsis. Other variables were not significantly different.Conclusions and Clinical Importance: Lateral body positioning significantly increases cervical esophageal transit time and affects the type of peristaltic wave generated by a swallow.
A Retrospective Analysis of Renal Carcinoma in the Horse
Authors: Wise L.N. , Bryan J.N. , Sellon D.C. , Hines M.T. , Ramsay J. , Seino K.K. 
Published: June 2009

Background:Renal carcinoma is a rare tumor of horses.Hypothesis:Presenting complaints and clinical signs of this disease are vague and early diagnosis increases survival time.Animals:Data were collected from the medical records of 4 horses presented to Washington State University as well as the 23 previously published case reports of horses with renal carcinoma.Methods:Retrospective study.Results:Renal carcinoma affects horses of all ages with most cases observed in geldings and Thoroughbreds. The most common presenting complaints are nonspecific and usually do not occur until late in the course of the disease. Routine laboratory results generally are unremarkable with no evidence of renal dysfunction. Urine and peritoneal fluid analyses are consistently abnormal, but the changes usually are nonspecific. Rectal palpation often allows detection of an abnormal kidney or a mass in the area of the kidney. Renal ultrasound examination is the most rewarding imaging procedure, and when combined with renal biopsy, antemortem diagnosis can be achieved. Renal carcinoma is both locally invasive and metastatic, necessitating careful staging for metastasis using thoracic radiography and abdominal ultrasound examination. If the tumor is localized to 1 kidney, nephrectomy is the treatment of choice. No chemotherapy or radiation treatment for renal carcinoma has been reported in the horse. Median survival for this series of cases was 11 days (0 days–1 year).Conclusions and Clinical Importance:Prognosis is poor to grave.
Soy Protein Isolate versus Meat‐Based Low‐Protein Diet for Dogs with Congenital Portosystemic Shunts
Authors: Proot S. , Biourge V. , Teske E. , Rothuizen J. 
Published: June 2009

Background: Both presurgical preparation and long‐term support of nonoperable dogs with congenital portosystemic shunts (CPSS) require optimal dietary management. Studies suggested that protein source may play an important role, with vegetable and dairy protein sources having better effects on hepatic encephalopathy (HE) than meat proteins.Objectives: Determine whether a low‐protein test diet with soy as its main protein source results in better scores than a control diet with the same composition but with poultry as its main protein source in dogs with CPSS.Methods: In a double‐blind cross‐over study, 16 dogs received each diet for 4 weeks. Dogs in group T first received the test diet and then the control diet, whereas dogs in group C were fed the diets in the opposite order. Different variables (body weight, body condition score, HE score, fecal score, CBC, plasma tests of liver function including NH3, and coagulation tests) were measured at the start of the study and after completion of each diet.Results: One‐way repeated measures ANOVA was performed. Plasma NH3 was significantly lower after the test diet than after the control diet. The test diet also resulted in significantly higher fibrinogen concentrations and lower prothrombin times. The HE score improved with both diets, with no significant difference between the 2 diets.Conclusions: Both diets achieved a significant improvement in HE score. The influence of the soy‐based diet on plasma NH3 concentration and coagulation parameters suggests that such a diet decreases the risk for HE and gives better support of liver function.
Accuracy of an Adrenocorticotropic Hormone (ACTH) Immunoluminometric Assay for Differentiating ACTH‐Dependent from ACTH‐Independent Hyperadrenocorticism in Dogs
Authors: Rodríguez Piñeiro M.I. , Benchekroun G. , De Fornel‐Thibaud P. , Maurey‐Guenec C. , Garnier F. , Rosenberg D. 
Published: June 2009

Background:Adrenocorticotropic hormone (ACTH) determination has been used for 30 years to distinguish ACTH‐dependent hyperadrenocorticism (ADHAC) from ACTH‐independent hyperadrenocorticism (AIHAC) in dogs. However, the few studies that have evaluated its diagnostic accuracy, based in the majority of cases on older assays, have been associated with systematic, but highly variable proportions of misclassified or unclassified cases.Objective:The purpose of the present study is to evaluate the accuracy of a validated ACTH immunoluminometric assay (ILMA) for differentiating between ADHAC and AIHAC.Animals:One hundred and nine dogs with hyperadrenocorticism were included: 91 with ADHAC and 18 with AIHAC.Methods:Retrospective study. Dogs displaying feedback inhibition after the dexamethasone suppression test, adrenal symmetry, or both were considered to have ADHAC. AIHAC was demonstrated by adrenal tumor histology. For each group, ACTH determination by ILMA was reviewed.Results:In the ADHAC group, plasma ACTH measurements ranged between 6 and 1250 pg/mL (median, 30 pg/mL). In the AIHAC group, all ACTH concentrations were below the lower quantification limit of the assay (<5 pg/mL). The 95% confidence interval was 85–100% for sensitivity and 97–100% for specificity in AIHAC diagnosis.Conclusion and Clinical Importance:No overlap in ACTH concentrations was observed between dogs with ADHAC and dogs with AIHAC. The use of a new technique with high analytical sensitivity made it possible to use a low threshold (5 pg/mL), avoiding the misclassification of some ADHAC cases with low, but quantifiable concentrations of ACTH. The assessment of ACTH concentrations by ILMA is an accurate tool for differentiating between ADHAC and AIHAC.
Serum Cardiac Troponin I Concentrations in Cattle with Cardiac and Noncardiac Disorders
Authors: Mellanby R.J. , Henry J.P. , Cash R. , Ricketts S.W. , Bexiga R. , Truyers I. , Mellor D.J. 
Published: June 2009

Background: Making a clinical diagnosis of pericarditis in cattle is difficult and additional diagnostic tests are needed to evaluate cattle with suspected pericarditis. Serum cardiac troponin I (cTnI) concentrations are increased in cattle with pericarditis, but the utility of measuring serum cTnI concentrations in cattle with suspected pericarditis in cattle remains unclear.Objectives: To determine if serum cTnI concentrations in cattle can be used to differentiate pericarditis from other cardiac disorders and noncardiac thoracic diseases.Animals: Seventy‐seven clinically diseased cattle and 19 healthy control cattle.Methods: Serum cTnI concentrations were measured using an Immunlite Troponin I immunometric chemiluminescent assay in consecutive cases of postmortem‐confirmed pericarditis (n = 18), endocarditis (n = 15), chronic suppurative pneumonia (n = 13), congenital heart disease (n = 10), reticulitis (n = 3), mediastinal abscess (n = 7), thymic lymphoma (n = 6), and caudal vena cava thrombosis (n = 5). Serum cTnI concentrations were measured in 19 healthy cattle.Results: Although serum cTnI concentrations were significantly higher in cattle with pericarditis compared with healthy cattle, they were not significantly different from concentrations in cattle with endocarditis, congenital cardiac disease, mediastinal abscess, reticulitis, caudal vena cava thrombosis, or chronic suppurative pneumonia.Conclusions: Serum cTnI cannot be used to distinguish cattle with pericarditis from cattle with other primary cardiac diseases. In addition, serum cTnI concentrations cannot distinguish between cattle with primary cardiac diseases and those with other noncardiac, intrathoracic disorders.
Calcium Reuptake Related Genes as a Cardiac Biomarker in Dogs with Chronic Mitral Valvular Insufficiency
Authors: Lee J.‐S. , Pak S.‐I. , Hyun C. 
Published: June 2009

Background: Gene expression linked to sarcoplasmic reticulum calcium reuptake (SRCR) is altered in humans and animals with heart failure.Hypothesis: The expression of SRCR genes in peripheral blood cells have the potential to be cardiac biomarkers of heart failure in dogs with chronic mitral valvular insufficiency (CMVI).Animals: Client‐owned 15 healthy control dogs and 23 small breed dogs with CMVI classified by severity, based on the classification system determined by the international small animal cardiac heart council.Methods: Prospective, controlled, observational study. The expression levels of SRCR genes (SERCA2α, PLN, and HAX‐1) were evaluated in peripheral blood of dogs at different stages of CMVI via real‐time reverse transcription polymerase chain reaction.Results: The mRNA expression levels of PLN and HAX‐1, but not SERCA2α were significantly (P= .08), reduced in dogs with moderate to severe CMVI. The fold change in PLN expression compared with control were 0.38 ± 0.07 (in group II) and 0.20 ± 0.10 (in group III), while HAX‐1 expression were 0.37 ± 0.06 (group II) and 0.41 ± 0.12 (group III). The expressions of PLN and HAX‐1 were significantly reduced in groups II and III (P < .05) but not in group I (P > .05). The reduced PLN and HAX‐1 expressions were highly correlated with the severity of heart failure (P < .001), vertebral heart score (P < .05), and left atrium to aortic root ratio (P < .05).Conclusions and Clinical Importance: PLN and HAX‐1 can be potential biomarkers for heart failure caused by CMVI.
Changes in Regulatory T Cells in Dogs with Cancer and Associations with Tumor Type
Authors: O'Neill K. , Guth A. , Biller B. , Elmslie R. , Dow S. 
Published: June 2009

Background: Regulatory T cells (Treg) have been shown to suppress antitumor immunity and often are increased in humans and rodents with cancer. However, Tregs have not been well studied in dogs with cancer and it is not known if certain tumor types are associated with increased Tregs.Hypothesis: We hypothesized that Treg percentages would be increased in dogs with cancer and that Treg percentages would be higher in dogs with certain types of cancer.Animals: The percentages and numbers of Tregs and nonregulatory T cells and B cells were assessed in 34 dogs with cancer and 9 age‐matched control dogs. Dogs evaluated included 14 dogs with sarcoma, 7 dogs with carcinoma, 7 dogs with lymphoma, and 6 dogs with mast cell tumor.Methods: Numbers and percentages of Tregs, CD4+, and CD8+ T cells and B cells were determined using flow cytometry and compared between control dogs and dogs with cancer.Results: The percentage of Tregs was significantly increased overall in dogs with cancer compared with control dogs. When tumor types were compared, Treg percentages were significantly increased in dogs with carcinoma. The Treg/CD8 T cell ratio was significantly higher in dogs with cancer compared with control dogs and was also significantly increased in 2 dogs with T‐cell lymphoma.Conclusions: Treg percentages in blood were increased in dogs with cancer, particularly in dogs with carcinoma. The Treg/CD8 ratio also identified tumor‐specific abnormalities in dogs with cancer. These findings indicate that tumor‐specific factors may affect Tregs in dogs.
At the Crossroads of Bacterial Metabolism and Virulence Factor Synthesis in Staphylococci
Authors: Somerville Greg A. , Proctor Richard A. 
Published: June 2009

SUMMARY

Bacteria live in environments that are subject to rapid changes in the availability of the nutrients that are necessary to provide energy and biosynthetic intermediates for the synthesis of macromolecules. Consequently, bacterial survival depends on the ability of bacteria to regulate the expression of genes coding for enzymes required for growth in the altered environment. In pathogenic bacteria, adaptation to an altered environment often includes activating the transcription of virulence genes; hence, many virulence genes are regulated by environmental and nutritional signals. Consistent with this observation, the regulation of most, if not all, virulence determinants in staphylococci is mediated by environmental and nutritional signals. Some of these external signals can be directly transduced into a regulatory response by two-component regulators such as SrrAB; however, other external signals require transduction into intracellular signals. Many of the external environmental and nutritional signals that regulate virulence determinant expression can also alter bacterial metabolic status (e.g., iron limitation). Altering the metabolic status results in the transduction of external signals into intracellular metabolic signals that can be “sensed” by regulatory proteins (e.g., CodY, Rex, and GlnR). This review uses information derived primarily using
Bacillus subtilis
and
Escherichia coli
to articulate how gram-positive pathogens, with emphasis on
Staphylococcus aureus
and
Staphylococcus epidermidis
, regulate virulence determinant expression in response to a changing environment.
The EVER Proteins as a Natural Barrier against Papillomaviruses: a New Insight into the Pathogenesis of Human Papillomavirus Infections
Authors: Lazarczyk Maciej , Cassonnet Patricia , Pons Christian , Jacob Yves , Favre Michel 
Published: June 2009

SUMMARYInfections by human papillomaviruses (HPVs) are the most frequently occurring sexually transmitted diseases. The crucial role of genital oncogenic HPV in cervical carcinoma development is now well established. In contrast, the role of cutaneous HPV in skin cancer development remains a matter of debate. Cutaneous beta-HPV strains show an amazing ubiquity. The fact that a few oncogenic genotypes cause cancers in patients suffering from epidermodysplasia verruciformis is in sharp contrast to the unapparent course of infection in the general population. Our recent investigations revealed that a natural barrier exists in humans, which protects them against infection with these papillomaviruses. A central role in the function of this HPV-specific barrier is played by a complex of the zinc-transporting proteins EVER1, EVER2, and ZnT-1, which maintain cellular zinc homeostasis. Apparently, the deregulation of the cellular zinc balance emerges as an important step in the life cycles not only of cutaneous but also of genital HPVs, although the latter viruses have developed a mechanism by which they can break the barrier and impose a zinc imbalance. Herein, we present a previously unpublished list of the cellular partners of EVER proteins, which points to future directions concerning investigations of the mechanisms of action of the EVER/ZnT-1 complex. We also present a general overview of the pathogenesis of HPV infections, taking into account the latest discoveries regarding the role of cellular zinc homeostasis in the HPV life cycle. We propose a potential model for the mechanism of function of the anti-HPV barrier.
Ecological Genomics of Marine Picocyanobacteria
Authors: Scanlan D. J. , Ostrowski M. , Mazard S. , Dufresne A. , Garczarek L. , Hess W. R. , Post A. F. , Hagemann M. , Paulsen I. , Partensky F. 
Published: June 2009

SUMMARYMarine picocyanobacteria of the generaProchlorococcusandSynechococcusnumerically dominate the picophytoplankton of the world ocean, making a key contribution to global primary production.Prochlorococcuswas isolated around 20 years ago and is probably the most abundant photosynthetic organism on Earth. The genus comprises specific ecotypes which are phylogenetically distinct and differ markedly in their photophysiology, allowing growth over a broad range of light and nutrient conditions within the 45°N to 40°S latitudinal belt that they occupy.SynechococcusandProchlorococcusare closely related, together forming a discrete picophytoplankton clade, but are distinguishable by their possession of dissimilar light-harvesting apparatuses and differences in cell size and elemental composition.Synechococcusstrains have a ubiquitous oceanic distribution compared to that ofProchlorococcusstrains and are characterized by phylogenetically discrete lineages with a wide range of pigmentation. In this review, we put our current knowledge of marine picocyanobacterial genomics into an environmental context and present previously unpublished genomic information arising from extensive genomic comparisons in order to provide insights into the adaptations of these marine microbes to their environment and how they are reflected at the genomic level.
Challenging a Paradigm: the Role of DNA Homology in Tyrosine Recombinase Reactions
Authors: Rajeev Lara , Malanowska Karolina , Gardner Jeffrey F. 
Published: June 2009

SUMMARYA classical feature of the tyrosine recombinase family of proteins catalyzing site-specific recombination, as exemplified by the phage lambda integrase and the Cre and Flp recombinases, is the ability to recombine substrates sharing very limited DNA sequence identity. Decades of research have established the importance of this short stretch of identity within the core regions of the substrates. Since then, several new enzymes that challenge this paradigm have been discovered and require the role of sequence identity in site-specific recombination to be reconsidered. The integrases of the conjugative transposons such as Tn916, Tn1545, and CTnDOT recombine substrates with heterologous core sequences. The integrase of the mobilizable transposon NBU1 performs recombination more efficiently with certain core mismatches. The integration of CTX phage and capture of gene cassettes by integrons also occur by altered mechanisms. In these systems, recombination occurs between mismatched sequences by a single strand exchange. In this review, we discuss literature that led to the formulation of the current strand-swapping isomerization model for tyrosine recombinases. The review then focuses on recent developments on the recombinases that challenged the paradigm that was derived from the studies of early systems.
Tumultuous Relationship between the Human Immunodeficiency Virus Type 1 Viral Infectivity Factor (Vif) and the Human APOBEC-3G and APOBEC-3F Restriction Factors
Authors: Henriet Simon , Mercenne Gaëlle , Bernacchi Serena , Paillart Jean-Christophe , Marquet Roland 
Published: June 2009

SUMMARY

The viral infectivity factor (Vif) is dispensable for human immunodeficiency virus type 1 (HIV-1) replication in so-called permissive cells but is required for replication in nonpermissive cell lines and for pathogenesis. Virions produced in the absence of Vif have an aberrant morphology and an unstable core and are unable to complete reverse transcription. Recent studies demonstrated that human APOBEC-3G (hA3G) and APOBEC-3F (hA3F), which are selectively expressed in nonpermissive cells, possess strong anti-HIV-1 activity and are sufficient to confer a nonpermissive phenotype. Vif induces the degradation of hA3G and hA3F, suggesting that its main function is to counteract these cellular factors. Most studies focused on the hypermutation induced by the cytidine deaminase activity of hA3G and hA3F and on their Vif-induced degradation by the proteasome. However, recent studies suggested that several mechanisms are involved both in the antiviral activity of hA3G and hA3F and in the way Vif counteracts these antiviral factors. Attempts to reconcile the studies involving Vif in virus assembly and stability with these recent findings suggest that hA3G and hA3F partially exert their antiviral activity independently of their catalytic activity by destabilizing the viral core and the reverse transcription complex, possibly by interfering with the assembly and/or maturation of the viral particles. Vif could then counteract hA3G and hA3F by excluding them from the viral assembly intermediates through competition for the viral genomic RNA, by regulating the proteolytic processing of Pr55
Gag
, by enhancing the efficiency of the reverse transcription process, and by inhibiting the enzymatic activities of hA3G and hA3F.
Signals, Regulatory Networks, and Materials That Build and Break Bacterial Biofilms
Authors: Karatan Ece , Watnick Paula 
Published: June 2009

SUMMARYBiofilms are communities of microorganisms that live attached to surfaces. Biofilm formation has received much attention in the last decade, as it has become clear that virtually all types of bacteria can form biofilms and that this may be the preferred mode of bacterial existence in nature. Our current understanding of biofilm formation is based on numerous studies of myriad bacterial species. Here, we review a portion of this large body of work including the environmental signals and signaling pathways that regulate biofilm formation, the components of the biofilm matrix, and the mechanisms and regulation of biofilm dispersal.