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The objectives of this study were to evaluate the prevalence of extended spectrum β-lactamase (ESBL) genes, AmpC-type β-lactamase (ACBL) genes, and plasmid mediated quinolone resistance (PMQR) genes in Salmonella isolated at a Veterinary Medical Teaching Hospital microbiology laboratory, examine trends in presence of these resistance genes, and to explore the correlation between phenotypic resistance and presence of specific genes. The presence of ESBL, ACBL, and PMQR genes were detected using a single, novel multiplex qPCR. Only the genes blaCMY–2 and blaTEM were detected in the 110 Salmonella isolates tested. PMQR genes were not detected in isolates screened. Of 94 third-generation cephalosporin resistant isolates, representing eight serotypes, 48% (n = 45) were positive for blaCMY–2 only and 50% (n = 47) were simultaneously positive for blaCMY–2 and blaTEM. Two third-generation cephalosporin resistant isolates were tested negative for all β-lactamase genes in our qPCR assay and likely house ESBL genes not screened for by our qPCR assay. A logistic regression model revealed that for serotype Dublin isolates (n = 38) the odds ratio for testing positive for blaTEM when compared to all other serotypes was 51.6 (95% CI: 4.01–664.03, p = 0.0029). For serotype Typhimurium (n = 9) the odds ratio for testing positive for blaTEM when compared to all other serotypes was 43.3 (95% CI: 1.76–1000, p = 0.0216). Overall, our results suggest that the prevalence of resistance to cephalosporins and fluoroquinolones due to ESBLs, ACBLs, and PMQR genes present in bovine nontyphoidal Salmonella enterica isolates has remained relatively constant in the isolates screened over a 14-year period.

The objectives of this study were to evaluate the prevalence of extended spectrum β-lactamase (ESBL) genes, AmpC-type β-lactamase (ACBL) genes, and plasmid mediated quinolone resistance (PMQR) genes in Salmonella isolated at a Veterinary Medical Teaching Hospital microbiology laboratory, examine trends in presence of these resistance genes, and to explore the correlation between phenotypic resistance and presence of specific genes. The presence of ESBL, ACBL, and PMQR genes were detected using a single, novel multiplex qPCR. Only the genes blaCMY–2 and blaTEM were detected in the 110 Salmonella isolates tested. PMQR genes were not detected in isolates screened. Of 94 third-generation cephalosporin resistant isolates, representing eight serotypes, 48% (n = 45) were positive for blaCMY–2 only and 50% (n = 47) were simultaneously positive for blaCMY–2 and blaTEM. Two third-generation cephalosporin resistant isolates were tested negative for all β-lactamase genes in our qPCR assay and likely house ESBL genes not screened for by our qPCR assay. A logistic regression model revealed that for serotype Dublin isolates (n = 38) the odds ratio for testing positive for blaTEM when compared to all other serotypes was 51.6 (95% CI: 4.01–664.03, p = 0.0029). For serotype Typhimurium (n = 9) the odds ratio for testing positive for blaTEM when compared to all other serotypes was 43.3 (95% CI: 1.76–1000, p = 0.0216). Overall, our results suggest that the prevalence of resistance to cephalosporins and fluoroquinolones due to ESBLs, ACBLs, and PMQR genes present in bovine nontyphoidal Salmonella enterica isolates has remained relatively constant in the isolates screened over a 14-year period.

Equine respiratory viruses remain a leading cause of equine morbidity and mortality, with the resurgence of certain infections, an increasing population of elderly, more susceptible horses, the growth of international equine commerce, and an expansion in geographic distribution of pathogens. The focus of rapid diagnosis of infectious diseases has also shifted recently, with the appearance and increasing importance of nucleic acid amplification-based techniques, primarily polymerase chain reaction (PCR), at the expense of traditional methods such as clinical microbiology. While PCR is fast, reliable, cost-effective, and more sensitive than conventional detection methods, careful interpretation of diagnostic test results is required, taking into account the clinical status of the patient, sample type, assay used and biological relevance of the detected viruses. The interpretation of common equine respiratory viruses such as influenza virus (EIV), alpha herpesviruses (EHV-1, EHV-4), arteritis virus (EAV) and rhinoviruses (ERAV, ERBV) is straight forward as causality can generally be established. However, the testing of less-characterized viruses, such as the gamma herpesviruses (EHV-2, EHV-5), may be confusing, considering their well-established host relationship and frequent detection in both diseased and healthy horses. For selected viruses, absolute quantitation (EHV-1 and EHV-4) and genotyping (EIV and EHV-1) has allowed additional information to be gained regarding viral state and virulence, respectively. This information is relevant when managing outbreaks so that adequate biosecurity measures can be instituted and medical interventions can be considered. The goal of this review is to help the equine practitioner navigate through the rapidly expanding field of molecular diagnostics for respiratory viruses and facilitate the interpretation of results.

A time-course study was performed over two years to investigate seasonal changes in copy numbers of different Grapevine leafroll associated virus (GLRaV) in infected grapevine (Vitis vinifera) in North America. We examined GLRaV-1, -2, -3, -4, and GLRaV-2RG in 104 grapevines that previously tested positive for one or more of these GLRaVs. Vines were selected from the Davis grapevine virus collection and the USDA National Clonal Germplasm Repository in northern California. Samples were collected from the beginning of the growing season (late April) until February; from April to November, mature leaf petioles were collected, and from December to February, cambial scrapings were taken from dormant cuttings. All samples were tested by RT-PCR and RT-qPCR; RT-qPCR was found to be the more sensitive technique. GLRaVs were more reliably detected in samples collected between August and February. Grapevines infected with GLRaV-2 were evenly detected throughout the year, while infection with GLRaV-1, -3 -4, and -2RG was best observed from November to February for both experimental years. Virus titer was lowest early in the growing season (April/May), and viral load differed among the GLRaVs. The viral load of GLRaV-3 remained unchanged, regardless of the season tested. Viruses associated with leafroll disease in grapevines were not uniformly distributed in both leaf petioles and cambium of grapevines; GLRaV-2 was the most evenly distributed virus in the grapevine, followed by GLRaV-1, GLRaV-3, and finally by GLRaV-4, which had the most uneven distribution.

A basic feature of infection caused by Borrelia burgdorferi, the etiological agent of Lyme borreliosis, is that persistent infection is the rule in its many hosts. The ability to persist and evade host immune clearance poses a challenge to effective antimicrobial treatment. A link between therapy failure and the presence of persister cells has started to emerge. There is growing experimental evidence that viable but noncultivable spirochetes persist following treatment with several different antimicrobial agents. The current study utilized the mouse model to evaluate if persistence occurs following antimicrobial treatment in disease-susceptible (C3H/HeJ [C3H]) and disease-resistant (C57BL/6 [B6]) mouse strains infected with B. burgdorferi strains N40 and B31 and to confirm the generality of this phenomenon, as well as to assess the persisters’ clinical relevance. The status of infection was evaluated at 12 and 18 months after treatment. The results demonstrated that persistent spirochetes remain viable for up to 18 months following treatment, as well as being noncultivable. The phenomenon of persistence in disease-susceptible C3H mice is equally evident in disease-resistant B6 mice and not unique to any particular B. burgdorferi strain. The results also demonstrate that, following antimicrobial treatment, both strains of B. burgdorferi, N40 and B31, lose one or more plasmids. The study demonstrated that noncultivable spirochetes can persist in a host following antimicrobial treatment for a long time but did not demonstrate their clinical relevance in a mouse model of chronic infection. The clinical relevance of persistent spirochetes beyond 18 months following antimicrobial treatment requires further studies in other animal models.

A basic feature of infection caused by Borrelia burgdorferi, the etiological agent of Lyme borreliosis, is that persistent infection is the rule in its many hosts. The ability to persist and evade host immune clearance poses a challenge to effective antimicrobial treatment. A link between therapy failure and the presence of persister cells has started to emerge. There is growing experimental evidence that viable but noncultivable spirochetes persist following treatment with several different antimicrobial agents. The current study utilized the mouse model to evaluate if persistence occurs following antimicrobial treatment in disease-susceptible (C3H/HeJ [C3H]) and disease-resistant (C57BL/6 [B6]) mouse strains infected with B. burgdorferi strains N40 and B31 and to confirm the generality of this phenomenon, as well as to assess the persisters’ clinical relevance. The status of infection was evaluated at 12 and 18 months after treatment. The results demonstrated that persistent spirochetes remain viable for up to 18 months following treatment, as well as being noncultivable. The phenomenon of persistence in disease-susceptible C3H mice is equally evident in disease-resistant B6 mice and not unique to any particular B. burgdorferi strain. The results also demonstrate that, following antimicrobial treatment, both strains of B. burgdorferi, N40 and B31, lose one or more plasmids. The study demonstrated that noncultivable spirochetes can persist in a host following antimicrobial treatment for a long time but did not demonstrate their clinical relevance in a mouse model of chronic infection. The clinical relevance of persistent spirochetes beyond 18 months following antimicrobial treatment requires further studies in other animal models.

Coccidioidomycosis is a fungal disease caused by either Coccidioides immitis or Coccidioides posadasii. Anecdotal evidence suggests that camelids are particularly susceptible to this disease and that a relatively large percentage of pneumonias in these animals are caused by Coccidioides spp. In a search of 21 y (1992–2013) of records from the California Animal Health and Food Safety Laboratory, we found 79 cases of coccidioidomycosis diagnosed in camelids; 66 (84%) had pneumonia and 13 (16%) had lesions only in organs other than the lungs. The organs most frequently affected were lung (84%) and liver (78%). Coccidioides spp. were the cause of pneumonia in 66 of 362 (18%) camelid cases during the study period. The lesions in affected organs were multifocal-to-coalescing pyogranulomas, which in most cases were visible grossly. Ten of the 12 formalin-fixed, paraffin-embedded lung samples tested by a universal Coccidioides spp. PCR assay were positive (4 C. immitis, 2 C. posadasii); the species could not be determined in 4 of the 10 cases positive by PCR. Coccidioidomycosis is an important cause of pneumonia in camelids in California, and can be caused by either C. immitis or C. posadasii.

Peritoneal transport characteristics and residual renal function require regular control and subsequent adjustment of the peritoneal dialysis (PD) prescription. Prescription models shall facilitate the prediction of the outcome of such adaptations for a given patient. In the present study, the prescription model implemented in the PatientOnLine software was validated in patients requiring a prescription change. This multicenter, international prospective cohort study with the aim to validate a PD prescription model included patients treated with continuous ambulatory peritoneal dialysis. Patients were examined with the peritoneal function test (PFT) to determine the outcome of their current prescription and the necessity for a prescription change. For these patients, a new prescription was modeled using the PatientOnLine software (Fresenius Medical Care, Bad Homburg, Germany). Two to four weeks after implementation of the new PD regimen, a second PFT was performed. The validation of the prescription model included 54 patients. Predicted and measured peritoneal Kt/V were 1.52 ± 0.31 and 1.66 ± 0.35, and total (peritoneal + renal) Kt/V values were 1.96 ± 0.48 and 2.06 ± 0.44, respectively. Predicted and measured peritoneal creatinine clearances were 42.9 ± 8.6 and 43.0 ± 8.8 L/1.73 m2/week and total creatinine clearances were 65.3 ± 26.0 and 63.3 ± 21.8 L/1.73 m2/week, respectively. The analysis revealed a Pearson's correlation coefficient for peritoneal Kt/V of 0.911 and Lin's concordance coefficient of 0.829. The value of both coefficients was 0.853 for peritoneal creatinine clearance. Predicted and measured daily net ultrafiltration was 0.77 ± 0.49 and 1.16 ± 0.63 L/24 h, respectively. Pearson's correlation and Lin's concordance coefficient were 0.518 and 0.402, respectively. Predicted and measured peritoneal glucose absorption was 125.8 ± 38.8 and 79.9 ± 30.7 g/24 h, respectively, and Pearson's correlation and Lin's concordance coefficient were 0.914 and 0.477, respectively. With good predictability of peritoneal Kt/V and creatinine clearance, the present model provides support for individual dialysis prescription in clinical practice. Peritoneal glucose absorption and ultrafiltration are less predictable and are likely to be influenced by additional clinical factors to be taken into consideration.

A 1-month-old Domestic Shorthair kitten was submitted for autopsy, with a history of upper respiratory tract infection and diarrhea. This was the third kitten from the same litter that had died with similar clinical findings within a period of 1 month. Severe conjunctivitis, rhinitis, tracheitis, and bronchointerstitial pneumonia were present, together with lymphohistiocytic colitis. Respiratory lesions were caused by infection with Felid herpesvirus 1. Colonic lesions were associated with the presence of long filamentous bacteria, identified as Clostridium piliforme, in the cytoplasm of epithelial cells. Our report describes a case of concurrent C. piliforme infection (Tyzzer’s disease) and feline rhinotracheitis in a kitten.

Thyroid disorders are common in chronic kidney disease. The aim: The purpose of this study was to compare thyroid gland disorders among healthy participants and renal transplant patients and to assess the duration of dialysis on thyroid disorders before transplantation. Material and methods: Prospective study during 12 months period included 80 participants divided into two groups. Study group of 40 patients with transplanted kidney was divided in two subgroups, according to the time spent on dialysis (i.e. under and over 72 months). The control group included 40 healthy participants. The exclusion criteria was represented by the previous thyroid disorders and systemic illnesses and treatment with drugs that interfere with thyroid function (amiodarone, propranolol, lithium). The blood samples were taken for standard laboratory analysis, total thyroid hormone levels. Serum level of free thyroxine (T4) and free triiodothyronine (T3) were assayed by RIA using commercially available kits. Subclinical hypothyroidism is defined by the finding of elevated thyroid-stimulating hormone (TSH) > 4.4 mmol/L and normal values of T3 and T4. Results: The relative distribution of the functional thyroid disorders is statistically significantly higher in the experimental group: the low T3 syndrome in 12.5% (n = 5) patients (p = 0.017); low T4 syndrome in 7.5% (n = 3) patients (p = 0.072) and subclinical hypothyroidism in 17.5% (n = 7) patients (p = 0.021). There is statistically significant difference in the relative representation (percentage) between respondents to 72 months and respondents over 72 months duration of hemodialysis, namely: low T3 syndrome, which is a higher percentage was recorded in patients up to 72 months duration of dialysis (19.23%), then subclinical hypothyroidism where a greater percentage recorded in subjects over 72 months duration of dialysis (35.71%) before transplantation. Conclusion: Considering that we are found in kidney transplant patients a significant link of subclinical hypothyroidism with decreased level of T3 and higher incidence of low T3 syndrome, which are associated with increased cardiovascular mortality and morbidity, and act as markers of survival patients after transplantation, it is necessary to conduct a periodically measuring levels of T3, T4 and TSH in these patients in order to assess the relationship between thyroid dysfunction and mortality risk in this population.

Background Alcoholic steatohepatitis (ASH) is caused in part by the effects of ethanol (EtOH) on hepatic methionine metabolism. Methods To investigate the phenotypic and epigenetic consequences of altered methionine metabolism in this disease, we studied the effects of 4-week intragastric EtOH feeding with and without the methyl donor betaine in cystathionine beta synthase (CβS) heterozygous C57BL/6J mice. Results The histopathology of early ASH was induced by EtOH feeding and prevented by betaine supplementation, while EtOH feeding reduced and betaine supplementation maintained the hepatic methylation ratio of the universal methyl donor S-adenosylmethionine (SAM) to the methyltransferase inhibitor S-adenosylhomocysteine (SAH). MethylC-seq genomic sequencing of heterozygous liver samples from each diet group found 2 to 4% reduced methylation in gene bodies, but not promoter regions of all autosomes of EtOH-fed mice, each of which were normalized in samples from mice fed the betaine-supplemented diet. The transcript levels of nitric oxide synthase (Nos2) and DNA methyltransferase 1 (Dnmt1) were increased, while those of peroxisome proliferator receptor-α (Pparα) were reduced in EtOH-fed mice, and each was normalized in mice fed the betaine-supplemented diet. DNA pyrosequencing of CβS heterozygous samples found reduced methylation in a gene body of Nos2 by EtOH feeding that was restored by betaine supplementation and was correlated inversely with its expression and positively with SAM/SAH ratios. Conclusions The present study has demonstrated relationships among EtOH induction of ASH with aberrant methionine metabolism that was associated with gene body DNA hypomethylation in all autosomes and was prevented by betaine supplementation. The data imply that EtOH-induced changes in selected gene transcript levels and hypomethylation in gene bodies during the induction of ASH are a result of altered methionine metabolism that can be reversed through dietary supplementation of methyl donors.

A single real-time multiplex quantitative PCR (qPCR) assay for the simultaneous detection of Grapevine virus A, B and D (GVA, GVB and GVD) was developed, using three different fluorescently labeled minor groove binding probes. This multiplex RT-qPCR was compared to singleplex RT-qPCR designed specifically for each virus and a conventional multiplex RT-PCR. The capacity of the multiplex RT-qPCR assay in detecting the three vitiviruses in mixed infections from a range of virus concentrations in the host was assessed. A series of cDNA derived from 48 different grapevine cultivars obtained from diverse geographical regions infected with various isolates and strains of GVA, GVB and GVD were subjected to singleplex, multiplex RT-qPCR, and conventional multiplex RT-PCR testing. The results showed that the developed multiplex RT-qPCR assay was a cost-effective diagnostic tool that could streamline the testing of grapevine vitiviruses, and replace the singleplex RT-qPCR assays, thus reducing time and labor while retaining the same sensitivity and specificity. In particular, no significant differences in detection limits were found between singleplex and multiplex RT-qPCR and specificity was not affected by the inclusion of the three primer/probe combinations within a multiplex RT-qPCR. Comparing the viral load for each virus using singleplex and multiplex RT-qPCR assays revealed no significant differences between the two assays in detecting GVB and GVD. However, while in detecting GVA using singleplex RT-qPCR assay, viral load was higher. Finally, the multiplex RT-qPCR assay was also more sensitive and time efficient than the conventional multiplex RT-PCR that was designed using degenerate primers to detect GVA, GVB and GVD. This multiplex RT-qPCR method could detect viruses in 95.83% of mixed infected samples as compared to 77.08% for multiplex RT-PCR.

Differential gene expression by Borrelia burgdorferi spirochetes during mammalian infection facilitates their dissemination as well as immune evasion. Modulation of gene transcription in response to host immunity has been documented with the outer surface protein C, but the influence of transcription of other genes is largely unknown. A low-density array (LDA) was developed to study transcriptional activity of 43 B. burgdorferi genes and 19 host genes that may be involved in various host–agent interactions. Gene transcription in heart, joint, and muscle tissue was compared in immunocompetent C3H and immunodeficient C3H-scid mice during early (3 weeks) and late (2 months) B. burgdorferi infection. Among all tissue types, levels of relative transcription of over 80% of B. burgdorferi genes tested were one- to nine-fold less in C3H mice compared to C3H-scid mice. At the later time point, all genes were transcribed in C3H-scid mice, whereas transcription of 16 genes out of 43 tested was not detected in analyzed tissues of C3H mice. Our data suggest that during infection of immunocompetent mice, a majority of B. burgdorferi genes tested are downregulated in response to acquired host immunity. LDA revealed variable patterns of host gene expression in different tissues and at different intervals in infected mice. Higher levels of relative expression for IL-10 during both early and late infection were detected in heart base, and it was unchanged in the tibiotarsal joint. Comparative analysis of B. burgdorferi and host genes transcriptional activity revealed that increased flaB mRNA during early infection was followed by increases of CCL7, CCL8, interleukin-10 (IL-10), and tumor necrosis factor-α (TNF-α) in all assessed tissue types. LDA represents a valuable approach for sensitive and quantitative gene transcription profiling and for understanding Lyme borreliosis.

The etiologic agent of Lyme disease, Borrelia burgdorferi, localizes preferentially in the extracellular matrix during persistence. In chronically infected laboratory mice, there is a direct association between B. burgdorferi and the proteoglycan decorin, which suggests that decorin has a role in defining protective niches for persistent spirochetes. In this study, the tissue colocalization of B. burgdorferi with decorin and the dynamics of borrelial decorin tropism were evaluated during chronic infection. Spirochetes were found to colocalize absolutely with decorin, but not collagen I in chronically infected immunocompetent C3H mice. Passive immunization of infected C3H-scid mice with B. burgdorferi-specific immune serum resulted in the localization of spirochetes in decorin-rich microenvironments, with clearance of spirochetes from decorin-poor microenvironments. In passively immunized C3H-scid mice, tissue spirochete burdens were initially reduced, but increased over time as the B. burgdorferi-specific antibody levels waned. Concurrent repopulation of the previously cleared decorin-poor microenvironments was observed with the rising tissue spirochete burden and declining antibody titer. These findings indicate that the specificity of B. burgdorferi tissue localization during chronic infection is determined by decorin, driven by the borrelia-specific antibody response, and fluctuates with the antibody response.

The laboratory mouse model of Lyme disease has revealed that Borrelia burgdorferi differentially expresses numerous outer surface proteins that influence different stages of infection (tick-borne transmission, tissue colonization, dissemination, persistence, and tick acquisition). Deletion of two such outer surface proteins, decorin-binding proteins A and B (DbpA/B), has been documented to decrease infectivity, impede early dissemination, and, possibly, prevent persistence. In this study, DbpA/B-deficient spirochetes were confirmed to exhibit an early dissemination defect in immunocompetent, but not immunodeficient, mice, and the defect was found to resolve with chronicity. Development of disease (arthritis and carditis) was attenuated only in the early stage of infection with DbpA/B-deficient spirochetes in both types of mice. Persistence of the DbpA/B-deficient spirochetes occurred in both immunocompetent and immunodeficient mice in a manner indistinguishable from that of wild-type spirochetes. Dissemination through the lymphatic system was evaluated as an underlying mechanism for the early dissemination defect. At 12 h, 3 days, 7 days, and 14 days postinoculation, DbpA/B-deficient spirochetes were significantly less prevalent and in lower numbers in lymph nodes than wild-type spirochetes. However, in immunodeficient mice, deficiency of DbpA/B did not significantly decrease the prevalence or spirochete numbers in lymph nodes. Complementation of DbpA/B restored a wild-type phenotype. Thus, the results indicated that deficiency of DbpA/B allows the acquired immune response to restrict early dissemination of spirochetes, which appears to be at least partially mediated through the lymphatic system.

The last several years have seen rapid development of technologies and methods that permit a detailed analysis of the genome and transcriptome of a single cell. Recent evidence from studies of single cells reveals that each cell type has a distinct lineage and function. The lineage and stage of development of each cell determine how they respond to each other and the environment. Experimental approaches that utilize single-cell analysis are effective means to understand how cell networks work in concert to coordinate a response at the population level; recent progress in single-cell analysis is offering a glimpse at the future.

Lyme neuroborreliosis—characterized as chronic, necrosuppurative to nonsuppurative, perivascular to diffuse meningoradiculoneuritis—was diagnosed in 2 horses with progressive neurologic disease. In 1 horse, Borrelia burgdorferi sensu stricto was identified by polymerase chain reaction amplification of B burgdorferi sensu stricto–specific gene targets ( ospA, ospC, flaB, dbpA, arp). Highest spirochetal burdens were in tissues with inflammation, including spinal cord, muscle, and joint capsule. Sequence analysis of ospA, ospC, and flaB revealed 99.9% sequence identity to the respective genes in B burgdorferi strain 297, an isolate from a human case of neuroborreliosis. In both horses, spirochetes were visualized in affected tissues with Steiner silver impregnation and by immunohistochemistry, predominantly within the dense collagenous tissue of the dura mater and leptomeninges.

Introduction: Acute kidney injury (AKI) is one of the major public health issues with constantly increasing incidence, with epidemiology and outcomes that vary substantially across the world. Aim: Aim of our study was to determine epidemiological characteristics and causes of AKI and to provide a comparison of our findings with data from other low and middle income countries. Methods: This retrospective observational study conducted during an 18-month period included 84 patients. Data were collected from hospital information system and patients’ medical records. All data were analyzed using descriptive statistics. Results: More than two-thirds of patients were older than 56 years. Most cases of AKI (54,76%) were hospital-acquired and predominantly developed in intensive care units (32,14%). Dominant risk factor was underlying chronic kidney disease (48,81%) and chronic heart failure (45,24. In majority of patients (73,81%) were identified multiple factors that may have contributed to AKI: infection (90,48%), prerenal factors (77,38%), nephrotoxic agents (69,05%), and sepsis (28,57%). Multiple organ failure was identified in 94,05% of patients: cardiovascular (64,56%), respiratory (58,23%) and hematological (56,96%) system. Half of all patients were alive at last observation day. Leading cause of death was infection/sepsis (21,43%), followed by cancer (16,67%) and shock (14,28%). Conclusion: Data on AKI show great variation, but general picture of AKI resembles more that from high income countries. The need for dialysis and overall mortality remains high. This highlights the importance of early recognition of AKI, timely referral to nephrologist and need for national guidelines and standardized protocols for AKI.

Introduction: Thyroid function disorders are common in patients with chronic kidney disease. The aim of this study was to compare thyroid function among patients on chronic hemodialysis (HD) and healthy participants and to assess duration of dialysis on thyroid disorders. Material and methods: Prospective study included 80 participants divided in two groups. Study group included 40 patients on HD who were divided in two subgroups, according to time on dialysis (under and over 72 months). Exclusion critheria were: previous thyroid disorders, systemic illnesses, criticaly ill patients and acute inflamatory diseases. Control group included 40 healthy participants. Blood samples were taken for standard laboratory analysis, total and free thyroid hormone levels. Results: In HD group we found statistycally significant lower mean values of T3 (1,36 ± 0.451, p72 months subclinical hypothyroidism was found more frequently in 35.71% (n = 5) (p = 0.04). Conclusion: Thyroid disorders are more common in patients on HD compared to general population. These findings suggest that thyroid function and morphology screening should be performed in HD patients.

The effectiveness of a new first-in-class antibiotic, tigecycline (glycylcycline), was evaluated during the early dissemination (1 week), early immune (3 weeks), or late persistent (4 months) phases of Borrelia burgdorferi infection in C3H mice. Mice were treated with high or low doses of tigecycline, saline (negative-effect controls), or a previously published regimen of ceftriaxone (positive-effect controls). Infection status was assessed at 3 months after treatment by culture, quantitative ospA real-time PCR, and subcutaneous transplantation of joint and heart tissue into SCID mice. Tissues from all saline-treated mice were culture and ospA PCR positive, tissues from all antibiotic-treated mice were culture negative, and some of the tissues from most of the mice treated with antibiotics were ospA PCR positive, although the DNA marker load was markedly decreased compared to that in saline-treated mice. Antibiotic treatment during the early stage of infection appeared to be more effective than treatment that began during later stages of infection. The viability of noncultivable spirochetes in antibiotic-treated mice (demonstrable by PCR) was confirmed by transplantation of tissue allografts from treated mice into SCID mice, with dissemination of spirochetal DNA to multiple recipient tissues, and by xenodiagnosis, including acquisition by ticks, transmission by ticks to SCID mice, and survival through molting into nymphs and then into adults. Furthermore, PCR-positive heart base tissue from antibiotic-treated mice revealed RNA transcription of several B. burgdorferi genes. These results extended previous studies with ceftriaxone, indicating that antibiotic treatment is unable to clear persisting spirochetes, which remain viable and infectious, but are nondividing or slowly dividing.

The effectiveness of antibiotic treatment was examined in a mouse model of Lyme borreliosis. Mice were treated with ceftriaxone or saline solution for 1 month, commencing during the early (3 weeks) or chronic (4 months) stages of infection withBorrelia burgdorferi. Tissues from mice were tested for infection by culture, PCR, xenodiagnosis, and transplantation of allografts at 1 and 3 months after completion of treatment. In addition, tissues were examined for the presence of spirochetes by immunohistochemistry. In contrast to saline solution-treated mice, mice treated with antibiotic were consistently culture negative, but tissues from some of the mice remained PCR positive, and spirochetes could be visualized in collagen-rich tissues. Furthermore, when some of the antibiotic-treated mice were fed on byIxodes scapularisticks (xenodiagnosis), spirochetes were acquired by the ticks, as determined based upon PCR results, and ticks from those cohorts transmitted spirochetes to naïve SCID mice, which became PCR positive but culture negative. Results indicated that following antibiotic treatment, mice remained infected with nondividing but infectious spirochetes, particularly when antibiotic treatment was commenced during the chronic stage of infection.

Peritoneal transport characteristics and residual renal function require regular control and subsequent adjustment of the peritoneal dialysis (PD) prescription. Prescription models shall facilitate the prediction of the outcome of such adaptations for a given patient. In the present study, the prescription model implemented in the PatientOnLine software was validated in patients requiring a prescription change. This multicenter, international prospective cohort study with the aim to validate a PD prescription model included patients treated with continuous ambulatory peritoneal dialysis. Patients were examined with the peritoneal function test (PFT) to determine the outcome of their current prescription and the necessity for a prescription change. For these patients, a new prescription was modeled using the PatientOnLine software (Fresenius Medical Care, Bad Homburg, Germany). Two to four weeks after implementation of the new PD regimen, a second PFT was performed. The validation of the prescription model included 54 patients. Predicted and measured peritoneal Kt/V were 1.52 ± 0.31 and 1.66 ± 0.35, and total (peritoneal + renal) Kt/V values were 1.96 ± 0.48 and 2.06 ± 0.44, respectively. Predicted and measured peritoneal creatinine clearances were 42.9 ± 8.6 and 43.0 ± 8.8 L/1.73 m(2)/week and total creatinine clearances were 65.3 ± 26.0 and 63.3 ± 21.8 L/1.73 m(2) /week, respectively. The analysis revealed a Pearson's correlation coefficient for peritoneal Kt/V of 0.911 and Lin's concordance coefficient of 0.829. The value of both coefficients was 0.853 for peritoneal creatinine clearance. Predicted and measured daily net ultrafiltration was 0.77 ± 0.49 and 1.16 ± 0.63 L/24 h, respectively. Pearson's correlation and Lin's concordance coefficient were 0.518 and 0.402, respectively. Predicted and measured peritoneal glucose absorption was 125.8 ± 38.8 and 79.9 ± 30.7 g/24 h, respectively, and Pearson's correlation and Lin's concordance coefficient were 0.914 and 0.477, respectively. With good predictability of peritoneal Kt/V and creatinine clearance, the present model provides support for individual dialysis prescription in clinical practice. Peritoneal glucose absorption and ultrafiltration are less predictable and are likely to be influenced by additional clinical factors to be taken into consideration.

The development of antibiotics changed the world of medicine and has saved countless human and animal lives. Bacterial resistance/tolerance to antibiotics have spread silently across the world and has emerged as a major public health concern. The recent emergence of pan-resistant bacteria can overcome virtually any antibiotic and poses a major problem for their successful control. Selection for antibiotic resistance may take place where an antibiotic is present: in the skin, gut, and other tissues of humans and animals and in the environment. Borrelia burgdorferi, the etiological agents of Lyme borreliosis, evades host immunity and establishes persistent infections in its mammalian hosts. The persistent infection poses a challenge to the effective antibiotic treatment, as demonstrated in various animal models. An increasingly heterogeneous subpopulation of replicatively attenuated spirochetes arises following treatment, and these persistent antimicrobial tolerant/resistant spirochetes are non-cultivable. The non-cultivable spirochetes resurge in multiple tissues at 12 months after treatment, with B. burgdorferi-specific DNA copy levels nearly equivalent to those found in shame-treated experimental animals. These attenuated spirochetes remain viable, but divide slowly, thereby being tolerant to antibiotics. Despite the continued non-cultivable state, RNA transcription of multiple B. burgdorferi genes was detected in host tissues, spirochetes were acquired by xenodiagnostic ticks, and spirochetal forms could be visualized within ticks and mouse tissues. A number of host cytokines were up- or down-regulated in tissues of both shame- and antibiotic-treated mice in the absence of histopathology, indicating a lack of host response to the presence of antimicrobial tolerant/resistant spirochetes.

Objective—To develop a quantitative PCR assay for detection of Borrelia burgdorferi DNA in formalin-fixed, paraffin-embedded tissues; compare results of this assay with results of immunohistochemical staining of tissues from seropositive dogs; and determine whether B burgdorferi DNA could be detected in renal tissues from dogs with presumptive Lyme nephritis. Design—Cohort study. Sample Population—Archived tissue samples from 58 dogs. Procedures—A quantitative PCR assay was performed on formalin-fixed, paraffin-embedded tissue sections from the dogs. Results were compared with results of immunohistochemical staining, B burgdorferi serostatus, clinical signs, and necropsy findings. Results—38 dogs were classified as having positive or equivocal results for Lyme borreliosis, and 20 were classified as having negative results on the basis of clinical signs, serologic findings, and pathologic abnormalities. Borrelia burgdorferi DNA was amplified from tissue samples from only 4 (7%) dogs, all of which had been classified as having positive or equivocal results for Lyme borreliosis and had signs of presumptive Lyme nephritis. Results of PCR assays of renal tissue were positive for only 1 dog, and there was no agreement between results of immunohistochemical staining (ie, detection of B burgdorferi antigen) and results of the PCR assay (ie, detection of B burgdorferi DNA) for renal tissues. Conclusions and Clinical Relevance—Results indicated that detection of B burgdorferi DNA in formalin-fixed, paraffin-embedded tissues is feasible, but that intact B burgdorferi DNA is rarely found in tissues from naturally infected dogs, even tissues from dogs with presumptive Lyme borreliosis. Further, findings support the contention that Lyme nephritis may be a sterile, immune complex disease.

In order to identify immunoreactive Bartonella henselae proteins, B. henselae antiserum from an experimentally infected cat was used to screen a B. henselae genomic DNA expression library. One immunoreactive phage clone contained a gene ( p26 ) with significant nucleotide identity with orthologs in brucellae, bartonellae, and several plant-associated bacteria. p26 gene sequences from four B. henselae strains, one B. koehlerae strain, and one B. clarridgeiae strain were cloned. Comparative nucleotide sequence analysis showed that p26 is a potential marker for molecular diagnosis of infection, as well as for identification to species level and genotyping of Bartonella sp. isolates. Alignment of the predicted amino acid sequences illustrated conserved putative protein features including a hydrophobic transmembrane region, a peptide cleavage site, and four dominant antigenic sites. Expression of p26 in Escherichia coli produced two proteins (26 and 27.5 kDa), both of which were reactive with feline anti- B. henselae antisera. Furthermore, murine hyperimmune serum raised against either recombinant protein reacted with both proteins. No reactivity to either recombinant protein was detected in nonimmune serum, and reactivity persisted as long as 20 weeks for one cat. The p26 protein product is an immunodominant antigen that is expressed during infection in cats as a preprotein and is subsequently cleaved to form mature P26.

In the mouse model of Lyme borreliosis, the host immune response during infection withBorrelia burgdorferiresults in the remission of carditis and arthritis, as well as global reduction of spirochete numbers in tissues, without elimination of infection (28). These events were recapitulated by passive transfer of immune serum from infected immunocompetent mice or T-cell-deficient mice to severe combined immunodeficient (SCID) mice. Previous studies have shown that immune serum is reactive against arthritis-related protein (Arp) and that Arp antiserum induces arthritis remission (16). However, although immune serum from T-cell-deficient mice induced disease remission, it was not reactive against Arp, suggesting that antibody to another antigen may be responsible. T-cell-deficient mouse immune serum was reactive to decorin binding protein A (DbpA). Therefore, DbpA antiserum was tested to determine its ability to induce disease remission in SCID mice. Antisera to Arp or DbpA induced both carditis and arthritis remission but did not significantly reduce spirochete numbers in tissues, based upon quantitativeflaBDNA analysis, nor did treatment affect RNA levels of several genes, includingarpanddbpA. Immunohistochemical labeling of spirochetes in hearts and joints during disease remission induced by adoptive transfer of lymphocytes, passive transfer of immune serum, or passive transfer of DbpA antiserum revealed that such treatment resulted in elimination of spirochetes from heart base and synovium but not vascular walls, tendons, or ligaments. These results suggest that Arp and DbpA antibodies may be active as disease-resolving components in immune serum but antibody against other antigens may be involved in reductions of spirochetes in tissues.

Borrelia burgdorferi, the agent of Lyme disease, andAnaplasma phagocytophilum, the agent of human anaplasmosis, are both transmitted byIxodessp. ticks and may occasionally coinfect a host. The population distributions of tick-transmittedB. burgdorferiinfection were assessed using quantitative PCR targeting theflaBgene ofB. burgdorferiin the ear, heart base, quadriceps muscle, skin, and tibiotarsal joint tissue of C3H mice previously infected withA. phagocytophilum. Population distributions ofAnaplasmainfection were assessed by targeting thep44gene.A. phagocytophilumin blood and serologic response to both agents were evaluated. Spirochete numbers were increased in the ears, heart base, and skin of coinfected mice, butAnaplasmanumbers remained constant. Antibody response toA. phagocytophilum, but notB. burgdorferi, was decreased in coinfected mice. These results suggest that coinfection withA. phagocytophilumandB. burgdorferimodulates pathogen burden and host antibody responses. This may be explained by the ability ofA. phagocytophilumto functionally impair neutrophils, important cells in the early defense againstB. burgdorferiinfection.

Several species of helicobacter have been isolated from laboratory mice, including H. bilis , H. hepaticus , H. muridarum , H. rodentium , and H. typhlonius , which appear to be the most common. The most widely used published method for molecular detection of these agents is PCR amplification of a conserved region of 16S rRNA, but differential speciation requires restriction enzyme digestion of the amplicons. This study was undertaken to determine PCR conditions that would simultaneously and specifically identify each of the five common species without restriction enzyme analyses. First, we designed novel and specific PCR primers for H. bilis , H. hepaticus , H. muridarum , H. rodentium , and H. typhlonius , using sequences from the heterologous regions of 16S rRNA. Because of comigration of amplified products, we next identified P17, an H. bilis- specific protein; P25, an H. hepaticus- specific protein; and P30, an H. muridarum- specific protein by screening genomic DNA expression libraries of each species. Primers were designed from these three genes, plus newly designed, species-specific 16S rRNA primers for H. rodentium and H. typhlonius that could be utilized for a five-plex PCR. The sizes of the amplicons from H. bilis , H. hepaticus , H. muridarum , H. rodentium , and H. typhlonius were 435, 705, 807, 191, and 122 bp, respectively, allowing simultaneous detection and effective discrimination among species.

To investigate cardiac involvement in the non-human primate (NHP) model of Lyme disease, we inoculated 39 adult Macaca mulatta with Borrelia burgdorferi sensu stricto strains N40 (BbN40) by needle (N=22, 14 immunocompetent (IC), seven permanently immunosuppressed (IS), and four transiently immunosuppressed (TISP)) or by tick-bite (N=4, all TISP) or strain 297 (Bb297) by needle (N=2 IS), or with B. garinii strains Pbi (N=4, 2 TISP and 2 IS), 793 (N=2, TISP) or Pli (N=2, TISP). Five uninfected NHPs were used as controls. Infection and inflammation was studied in the hearts and the aorta removed at necropsy 2-32 months after inoculation by (1) HE and trichrome-staining; (2) immunohistochemistry and digital image analysis; (3) Western blot densitometry; and (4) TaqMan RT-PCR. All NHPs inoculated with BbN40 became infected and showed carditis at necropsy. The predominant cells were T cells, plasma cells, and macrophages. There was increased IgG and IgM in the heart independent of immunosuppression. The B-cell chemokine BLC was significantly increased in IS-NHPs. There was increased deposition of the complement membrane attack complex (MAC) in TISP and IS-NHPs. The spirochetal load was very high in all BbN40-inoculated IS-NHPs but minimal if any in IC or TISP NHPs. Double-immunostaining revealed that many spirochetes in the heart of BbN40-IS NHPs had MAC on their membranes. We conclude that carditis in NHPs infected with B. burgdorferi is frequent and can persist for years but is mild unless they are immunosupressed.

Lyme borreliosis is a multisystemic disease caused by various genospecies of the spirocheteBorrelia burgdorferi. To investigate muscle involvement in the nonhuman primate (NHP) model of Lyme disease, 16 adultMacaca mulattaanimals inoculated with strain N40 ofB. burgdorferisensu strictu by syringe or by tick bite or with strain Pbi ofB. burgdorferigenospeciesgariniiby syringe were studied. Animals were necropsied while immunosuppressed on day 50 (two animals each inoculated withB.burgdorferiN40 by syringe and withB.gariniiPbi by syringe) or on day 90, 40 days after immunosuppression had been discontinued (four animals each inoculated with strain N40 by syringe, with strain N40 by tick bite, and with strain Pbi by syringe). Skeletal muscles removed at necropsy were studied by (i) microscopic examination of hematoxylin-eosin-stained sections for inflammation and tissue injury; (ii) immunohistochemical and digital image analyses for antibody and complement deposition and cellular inflammation; (iii) Western blot densitometry for the presence of antibodies; and (iv) reverse transcription-PCR for measurement of the spirochetal load or C1q (the first component of the complement cascade) synthesis. The results showed that N40 was more infectious for NHPs than Pbi. NHPs inoculated with N40 but not with Pbi developed myositis. The inflammation in skeletal muscle was more severe in NHPs inoculated with N40 by syringe than in those inoculated by tick bite. The predominant cells in the inflammatory infiltrate were T cells and plasma cells. The deposition of antibody and complement in inflamed muscles from N40-inoculated NHPs was significantly higher than that in Pbi-inoculated NHPs. The spirochetal load was very high in the two N40-inoculated NHPs examined while they were immunosuppressed but decreased to minimal levels in the NHPs when immunocompetence was restored. We conclude that myositis can be a prominent feature of Lyme borreliosis depending on the infecting organism and host immune status.

The population dynamics of Borrelia burgdorferi were quantified by real-time PCR targeting the flaB gene in skin (inoculation site, noninoculation site, and ear), heart (heart base and ventricle), quadriceps muscle, and the tibiotarsal joint at 1, 2, 4, 6, and 8 weeks after intradermal inoculation in C3H and C3H- scid mice. In addition, RNA transcription was assessed for several prototype genes, including flaB , ospA , ospC , dbpA , arp , vlsE , fbp , oppA-2 , and p37-42 . Spirochete numbers were equivalent in C3H and C3H- scid mice at 1 or 2 weeks and then declined in C3H mice, but they continued to rise and then plateaued in C3H- scid mice. Gene transcription was likewise higher in C3H- scid mice than in C3H mice, particularly at 4 or more weeks of infection. Gene transcription showed variation among tissues, with the highest levels of transcription in heart and joint tissue, which are sites of inflammation.

Tick saliva contains anti-inflammatory and immunosuppressive substances that facilitate blood feeding and enhance tick-vectored pathogen transmission, including Anaplasma phagocytophila,an etiologic agent of granulocytic ehrlichiosis. As such, inflammation at a tick-feeding site is strikingly different than that typically observed at other sites of inflammation. Up-regulation of CD11b/CD18 occurs in host granulocytes following interaction or infection withA phagocytophila, and the absence of CD11b/CD18 results in early increases in bacteremia. We hypothesized that β2 integrin–dependent infection kinetics and leukocyte extravasation are important determinants of neutrophil trafficking to, and pathogen acquisition at, tick-feeding sites.A phagocytophila infection kinetics were evaluated in CD11a/CD18, CD11b/CD18, and CD18 knock-out mice using quantitative polymerase chain reaction (PCR) of blood, ticks, and skin biopsies in conjunction with histopathology. A marked increase in the rate ofA phagocytophila infection of neutrophils and pathogen burden in blood followed tick feeding. Infection kinetics were modified by β2 integrin expression and systemic neutrophil counts. Significant neutrophil-pathogen trafficking was observed to both suture and tick sites. Despite the prominent role for β2 integrins in neutrophil arrest in flowing blood, successful pathogen acquisition by ticks occurred in the absence of β2 integrins. Establishment of feeding pools that rely less on leukocyte trafficking and more on small hemorrhages may explain the ready amplification of A phagocytophila DNA from ticks infested on CD11/CD18-deficient mouse strains.

Xenodiagnosis by ticks was used to determine whether spirochetes persist in mice after 1 month of antibiotic therapy for vectorborne Borrelia burgdorferi infection. Immunofluorescence and polymerase chain reaction (PCR) were used to show that spirochetes could be found in Ixodes scapularis ticks feeding on 4 of 10 antibiotic-treated mice up to 3 months after therapy. These spirochetes could not be transmitted to naive mice, and some lacked genes on plasmids correlating with infectivity. By 6 months, antibiotic-treated mice no longer tested positive by xenodiagnosis, and cortisone immunosuppression did not alter this result. Nine months after treatment, low levels of spirochete DNA could be detected by real-time PCR in a subset of antibiotic-treated mice. In contrast to sham-treated mice, antibiotic-treated mice did not have culture or histopathologic evidence of persistent infection. These results provide evidence that noninfectious spirochetes can persist for a limited duration after antibiotics but are not associated with disease in mice.

The immune response to Borrelia burgdorferi , the causative agent of Lyme disease, is complex. We studied the immunoglobulin M (IgM) and IgG antibody response to N40Br, a sensu stricto strain, in the rhesus macaque(nonhuman primate [NHP]) model of infection to identify the spirochetal protein targets of specific antibody. Antigens used in enzyme-linked immunosorbent assays were whole-cell sonicates of the spirochete and recombinant proteins of B. burgdorferi . Immunoblotting with a commercially available strip and subsequent quantitative densitometry of the bands were also used. Sera from four different groups of NHPs were used: immunocompetent, transiently immunosuppressed, extended immunosuppressed, and uninfected. In immunocompetent and transiently immunosuppressed NHPs, there was a strong IgM and IgG response. Major proteins for the early IgM response were P39 and P41 and recombinant BmpA and OspC. Major proteins for the later IgG response were P39, P41, P18, P60, P66, and recombinant BmpA and DbpA. There was no significant response in the NHPs to recombinant OspA or to Arp, a 37-kDa protein that elicits an antibody response during infection in mice. Most antibody responses, except for that to DbpA, were markedly diminished by prolonged dexamethasone treatment. This study supports the hypothesis that recombinant proteins may provide a useful adjunct to current diagnostic testing for Lyme borreliosis.

The agent of human granulocytic ehrlichiosis (aoHGE) is a tick-borne, obligate intracellular, granulocytotropic bacterium able to infect numerous host species. Given its unique niche and the leukopenia often noted with infection, we investigated the effect of acute aoHGE infection on neutrophil activation by evaluating surface expression of the beta 2 integrin CD11b/CD18 in a mouse model using FACS analysis. Infection resulted in neutrophil activation with up-regulation of CD11b/CD18 in multiple strains of mice, however, hematologic analysis showed no apparent role for CD11b/CD18 in mediating peripheral leukopenia. Because IFN-gamma is an important cytokine during granulocytic ehrlichiosis and is known to activate leukocytes, we investigated the potential role of IFN-gamma in CD11b/CD18 up-regulation. Neutrophils from IFN-gamma knock-out mice became activated during aoHGE infection, however, the kinetics of activation differed from wild-type mice. In addition, activation correlated directly with the presence of bacteria because neutrophils with large intracytoplasmic morula also expressed higher levels of CD11b/CD18. CD11b/CD18 seemed to be critical to early bacterial clearance and killing in vivo because infection of mice with targeted genetic disruption of CD11b/CD18 resulted in an initial increase in bacterial burden compared with wild-type mice. Similarly, in vitro culture of neutrophils from infected CD11b/CD18 knock-out mice resulted in a marked increase in bacterial proliferation compared with congenic controls. The data support crucial roles of CD11b/CD18 and IFN-gamma-mediated cell activation as mechanisms that limit bacterial replication.

Anaplasma phagocytophilum is a tick-transmitted bacterial pathogen of humans and animals comprising strains that cause clinical disease in people, dogs and horses (the pathogenic A. phagocytophilum "genospecies") and more distantly related strains. A rodent-adapted genospecies named DU1, found primarily in woodrats, is unable to infect horses. We developed a real-time PCR (RT-PCR) assay, which targets an 85 base pair region of the ank gene and is specific for the pathogenic genospecies of A. phagocytophilum from North America. Thirty DNA samples from A. phagocytophilum RT-PCR-positive rodents and ticks for which the ank gene had previously been sequenced and had been identified as either the pathogenic genospecies or DU1 were used for validation. All nine samples with the pathogenic genospecies tested positive using the new RT-PCR and all 21 samples with the DU1 genospecies tested negative. Two strains from which the whole genome has been sequenced and are known to be pathogenic (A. phagocytophilum, strain HZ isolated from a human from New York and strain MRK isolated from a horse from California) both tested positive using the new RT-PCR assay. We also tested blood from 20 horses and six dogs that were RT-PCR-positive using a previously validated RT-PCR protocol: all were PCR-positive using the new assay as well. The assay has high efficiency and reproducibility and there was no cross-reaction with related and tick-borne bacteria tested, although the assay cross-reacts with the ungulate-adapted genospecies Ap-Variant 1. This new RT-PCR assay will aid in future research on the ecology and epidemiology of A. phagocytophilum by allowing researchers to easily identify the pathogenic genospecies in reservoir hosts and vectors.