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Objective: Pulmonary hypertension can cause left ventricular diastolic dysfunction through ventricular interdependence. Moreover, diastolic dysfunction has been linked to adverse outcomes after lung transplant. The impact of lung transplant on diastolic dysfunction in recipients with pretransplant pulmonary hypertension is not defined. In this cohort, we aimed to assess the prevalence of diastolic dysfunction, the change in diastolic dysfunction after lung transplant, and the impact of diastolic dysfunction on lung transplant outcomes., Methods: In a large, single-center database from January 2011 to September 2021, single or bilateral lung transplant recipients with pulmonary hypertension (mean pulmonary artery pressure > 20 mm Hg) were retrospectively identified. Those without a pre- or post-transplant echocardiogram within 1 year were excluded. Diastolic dysfunction was diagnosed and graded according to the American Society of Echocardiography 2016 guideline on assessment of diastolic dysfunction (present, absent, indeterminate). McNemar's test was used to examine association between diastolic dysfunction pre- and post-transplant. Kaplan-Meier and Cox regression analysis were used to assess associations between pre-lung transplant diastolic dysfunction and post-lung transplant 1-year outcomes, including mortality, major adverse cardiac events, and bronchiolitis obliterans syndrome grade 1 or higher-free survival., Results: Of 476 primary lung transplant recipients, 205 with pulmonary hypertension formed the study cohort (mean age, 56.6 ± 11.9 years, men 61.5%, mean pulmonary artery pressure 30.5 ± 9.8 mm Hg, left ventricular ejection fraction < 55% 9 [4.3%]). Pretransplant, diastolic dysfunction was present in 93 patients (45.4%) (grade I = 8, II = 84, III = 1), absent in 16 patients (7.8%), and indeterminate in 89 patients (43.4%), and 7 patients (3.4%) had missing data. Post-transplant, diastolic dysfunction was present in 7 patients (3.4%) (grade I = 2, II = 5, III = 0), absent in 164 patients (80.0%), and indeterminate in 15 patients (7.3%), and 19 patients (9.3%) had missing data. For those with diastolic dysfunction grades in both time periods (n = 180), there was a significant decrease in diastolic dysfunction post-transplant (148/169 patients with resolved diastolic dysfunction; McNemar's test P < .001). Pretransplant diastolic dysfunction was not associated with major adverse cardiac events (hazard ratio [HR], 1.08, 95% CI, 0.72-1.62; P = .71), bronchiolitis obliterans syndrome-free survival (HR, 0.67, 95% CI, 0.39-1.56; P = .15), or mortality (HR, 0.70, 95% CI, 0.33-1.46; P = .34) at 1 year., Conclusions: Diastolic dysfunction is highly prevalent in lung transplant candidates with normal left ventricular systolic function and pulmonary hypertension, and resolves in most patients after lung transplant regardless of patient characteristics. Pre-lung transplant diastolic dysfunction was not associated with adverse lung or cardiac outcomes after lung transplant. Collectively, these findings suggest that the presence of diastolic dysfunction in lung transplant recipients with pulmonary hypertension has no prognostic significance, and as such diastolic dysfunction and the associated clinical syndrome of heart failure with preserved ejection fraction should not be considered a relative contraindication to lung transplant in such patients., Competing Interests: Conflict of Interest Statement Dr Huddleston has received grant funding for clinical trials from TransMedics. All other authors reported no conflicts of interest. The Journal policy requires editors and reviewers to disclose conflicts of interest and to decline handling or reviewing manuscripts for which they may have a conflict of interest. The editors and reviewers of this article have no conflicts of interest., (Copyright © 2023 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)

The COVID-19 pandemic caused by the SARS-CoV-2 virus brought many primatology research programs and conservation efforts to a halt. After Madagascar closed its borders during March 2020, many on-site international project leaders and researchers returned to their home countries when their programs were delayed or canceled. Madagascar remained closed to travelers until November 2021, when it reopened to international flights. The 20-month absence of international researchers allowed many local Malagasy program staff, wildlife professionals, and community leaders to step into new leadership roles and responsibilities. Many programs that already had strong Malagasy leadership and meaningful collaborations with local communities flourished, while others either swiftly strengthened these attributes or faced challenges from pandemic-related travel restrictions. Here, we describe how the coronavirus pandemic events of 2020-2021 initiated long-overdue shifts in outdated models of internationally led primate research and education projects in communities living alongside primates at risk of extinction. We discuss the benefits and challenges of pandemic-induced changes within five primatological outreach projects, as well as how we can use these experiences to improve community-led environmental education and conservation awareness in the future., (© 2023 Wiley Periodicals LLC.)

Stroke remains an important risk during transcatheter aortic valve implantation (TAVI). Though the use of the double-filter Sentinel cerebral protection system (Boston Scientific, Marlborough, MA, USA) may lower the stroke risk, the deployment of this device requires manipulation within the aortic arch and cranial arch vessels potentially causing dislodgment of atherosclerotic debris in the process thereby possibly offsetting its benefit with regards to reducing cerebral embolization. Apart from patient selection, minimizing maneuvering during deployment may improve the safety of device deployment. In this context, we illustrate a case using three-dimensional computed tomography (CT) - overlay to facilitate Sentinel cerebral protection system deployment during TAVI. Emphasis in this case rests on demonstration of how aforementioned periprocedural imaging may facilitate negotiation of anatomical variants and avoid inadvertent cannulation of an anomalous left vertebral artery originating from the aortic arch. Imaging guidance with this concept may minimize device manipulation and reduce the risk of cerebral embolization. Further systematic evaluation is needed to demonstrate whether this approach improves clinical outcomes., (Copyright © 2020. Published by Elsevier Inc.)

Objective: The purpose of this study was to determine the relationship between blood product transfusion, with or without recombinant human activated factor VIIa, and survival after lung transplantation., Design: Retrospective analysis of a single center with follow-up out to 6 years post-transplantation., Setting: Single-center academic lung transplantation program., Participants: The study comprised 265 adult patients who underwent single or bilateral sequential lung transplantation from March 2011 to June 2017., Interventions: Overall survival using Kaplan-Meier curves was compared among the following 3 cohorts: those not transfused with blood products, those transfused with blood products, and those given blood products and recombinant human activated factor VIIa. Cox proportional hazards regression was used to estimate hazard ratios (HRs), confidence intervals (CIs), and p values., Measurements and Main Results: Seventy-eight patients received no packed red blood cell transfusions, 149 received packed red blood cell transfusions, and 38 received both packed red blood cell transfusions and recombinant human activated factor VII. Packed red blood cell transfusion was associated with an increased risk of mortality that did not reach statistical significance (HR 2.168, CI 0.978-4.805; p = 0.057). Additional packed red blood cells beyond 15 U were associated with worsened survival (HR 1.363, CI 1.137-1.633; p = 0.001), but recombinant human activated factor VIIa did not increase the risk of mortality., Conclusion: Blood product transfusion during and after lung transplantation is associated with decreased survival, especially with large-volume transfusions. Survival is not worse with recombinant human activated factor VIIa administration, but additional studies are needed to determine whether recombinant human activated factor VIIa administration reduces the need for blood product transfusions., Competing Interests: Declaration of interest for all other authors None., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: Tracheostomy is an important adjunct for lung transplant patients requiring prolonged ventilation. We explored the effects of post-transplant tracheostomy on survival and bronchiolitis obliterans syndrome after lung transplant., Methods: A retrospective, single center analysis was performed on all lung transplant recipients during the Lung Allocation Score (LAS) era. Risk factors for post-transplant tracheostomy or death within 30 days were assessed. Kaplan-Meier estimates and Cox proportional hazards models were used to examine the association between tracheostomy within 30 days after transplant and survival at 1 and 3 years. A total of 403 patients underwent single or bilateral lung transplant between May 2005 and February 2016 with complete data for 352 cases, and 35 patients (9.9%) underwent tracheostomy or died (N = 10, 2.8%) within 30 days., Results: In adjusted analyses, primary graft dysfunction grade 3 (PGD3) was associated with a composite end point of tracheostomy or death within 30 days (HR 3.11 (1.69, 5.71), P-value < .001). Tracheostomy within 30 days was associated with decreased survival at 1(HR 4.25 [1.75, 10.35] P-value = .001) and 3 years (HR 2.74 [1.30, 5.76], P-value = .008), as well as decreased bronchiolitis obliterans (BOS)-free survival at 1 (HR 1.87 [1.02, 3.41] P-value = .042) and 3 years (HR 2.15 [1.33, 3.5], P-value = .002)., Conclusion: Post-transplant tracheostomy is a marker for advanced lung allograft dysfunction with significant reduction in long-term overall and BOS-free survival., (© 2019 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Background: United States veterans have substantially worse baseline health status than the general population, which may limit the health benefits of transcatheter aortic valve replacement (TAVR). The aim of this study is to quantify the health benefits of TAVR in veterans undergoing the procedure within the United States Department of Veterans Affairs (VA) health-care system., Methods: We prospectively evaluated heath status in 131 elderly veterans undergoing TAVR in the VA healthcare system between 2015 and 2017. Health status was assessed at baseline and 30 days post procedure using the Kansas City Cardiomyopathy Questionnaire 12 (KCCQ-12). Totals and domain-specific (physical limitation, symptoms, quality of life, and social limitation) health statuses were measured and analyzed with a paired t-test. We also conducted stratified analysis by baseline New York Heart Association functional class and N-terminal pro-b type natriuretic peptide levels., Results: Mean patient age was 77 ± 8 years and average Society of Thoracic Surgeons (STS) score was 4.4 (interquartile range, 3-7). Transfemoral access and balloon-expandable valves were used in 118 cases (92%) and 108 cases (83%), respectively. At baseline, overall health status was poor (overall score, 43 ± 19). After TAVR, significant improvements in overall health status (30 ± 18) and domain-specific health status were seen (improvements in physical limitation, 12 ± 20; symptoms, 23 ± 23; quality of life, 20 ± 17; social limitation, 22 ± 21; all P<.001). The majority of patients (88%) had moderate to large improvements in health status. A favorable outcome (alive with KCCQ-12 overall score >60 at 30 days) was seen in 78% of patients., Conclusion: Among elderly veterans with severe aortic stenosis, TAVR is associated with significant improvements in short-term health status.

Purpose: Quality, patient safety and value are important topics for graduate medical education (GME). Spaced education delivers case-based content in a structured longitudinal experience. Use of spaced education to deliver quality and safety education in GME at an institutional level has not been previously evaluated., Objectives: To implement a spaced education course in quality, safety and value; to assess learner satisfaction; and to describe trainee knowledge in these areas., Methods: We developed a case-based spaced education course addressing learning objectives related to quality, safety and value. This course was offered to residents and fellows about two-thirds into the academic year (March 2014) and new trainees during orientation (June 2014). We assessed learner satisfaction by reviewing the course completion rate and a postcourse survey, and trainee knowledge by the per cent of correct responses., Results: The course was offered to 1950 trainees. A total of 305 (15.6%) enrolled in the course; 265/305 (86.9%) answered at least one question, and 106/305 (34.8%) completed the course. Fewer participants completed the March programme compared with the orientation programme (42/177 (23.7%) vs 64/128 (50.0%), p<0.001). Completion rates differed by specialty, 80/199 (40.2%) in non-surgical specialties compared with 16/106 (24.5%) in surgical specialties (p=0.008). The proportion of questions answered correctly on the first attempt was 53.2% (95% CI 49.4% to 56.9%). Satisfaction among those completing the programme was high., Conclusions: Spaced education can help deliver and assess learners' understanding of quality, safety and value principles. Offering a voluntary course may result in low completion. Learners were satisfied with their experience and were introduced to new concepts., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/)

Background: In Ukraine, HIV-infection, injection drug use, and incarceration are syndemic; however, few services are available to incarcerated people who inject drugs (PWIDs). While data are limited internationally, within-prison drug injection (WP-DI) appears widespread and may pose significant challenges in countries like Ukraine, where PWIDs contribute heavily to HIV incidence. To date, WP-DI has not been specifically examined among HIV-infected prisoners, the only persons that can transmit HIV., Methods: A convenience sample of 97 HIV-infected adults recently released from prison within 1-12 months was recruited in two major Ukrainian cities. Post-release surveys inquired about WP-DI and injection equipment sharing, as well as current and prior drug use and injection, mental health, and access to within-prison treatment for HIV and other comorbidities. Logistic regression identified independent correlates of WP-DI., Results: Complete data for WP-DI were available for 95 (97.9%) respondents. Overall, 54 (56.8%) reported WP-DI, among whom 40 (74.1%) shared injecting equipment with a mean of 4.4 (range 0-30) other injectors per needle/syringe. Independent correlates of WP-DI were recruitment in Kyiv (AOR 7.46, p=0.003), male gender (AOR 22.07, p=0.006), and active pre-incarceration opioid use (AOR 8.66, p=0.005)., Conclusions: Among these recently released HIV-infected prisoners, WP-DI and injection equipment sharing were frequent and involved many injecting partners per needle/syringe. The overwhelming majority of respondents reporting WP-DI used opioids both before and after incarceration, suggesting that implementation of evidence-based harm reduction practices, such as opioid substitution therapy and/or needle/syringe exchange programmes within prison, is crucial to addressing continuing HIV transmission among PWIDs within prison settings. The positive correlation between Kyiv site and WP-DI suggests that additional structural interventions may be useful., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Background: Ukraine's HIV epidemic, primarily affecting people who inject drugs (PWID), is expanding and transitioning despite free opioid substitution therapy (OST) and antiretroviral therapy (ART), two effective ways to reduce HIV transmission. Police detention of PWID not resulting in a formal charge or imprisonment is common, but its prevalence and impact on health are not known., Method: HIV-infected individuals (N=97) released from prison within one year were recruited and surveyed in two HIV-endemic Ukrainian cities about post-release police detention experiences. Data on the frequency of police detention, related adverse events, and impact on OST and ART continuity were collected, and correlates of detention were examined using logistic regression., Results: Detention responses were available for 94 (96.9%) participants, of which 55 (58.5%) reported police detentions (mean=9.4 per person-year). For those detained while prescribed OST (N=28) and ART (N=27), medication interruption was common (67.9% and 70.4%, respectively); 23 of 27 participants prescribed OST (85.2%) were detained en route to/from OST treatment. Significant independent correlates of detention without charges included post-release ART prescription (AOR 4.98, p=0.021), current high-risk injection practices (AOR 5.03, p=0.011), male gender (AOR 10.88, p=0.010), and lower lifetime months of imprisonment (AOR 0.99, p=0.031)., Conclusions: HIV-infected individuals recently released from prison in Ukraine experience frequent police detentions, resulting in withdrawal symptoms, confiscation of syringes, and interruptions of essential medications, including ART and OST. Structural changes are urgently needed to reduce police detentions in order to control HIV transmission and improve both individual and public health., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

Celiac aortic localization of mycotic pseudoaneurysm is serious. The conventional treatment, resection of infected tissues with in situ revascularization, is associated with a high surgical morbid-mortality rate. We report a case of mycotic pseudoaneurysm of the abdominal aorta involving visceral arteries excluded by an aortic endoprosthesis after visceral debranching. A 69-year-old man developed a celiac mycotic pseudoaneurysm after an acute prostatitis with septicemia (Escherichia coli). He underwent celiac aortic exclusion by an aortic endoprosthesis associated with a retrogade visceral bypass at the same time, under adequate antibiotherapy. Postoperative course was uneventful. After 18-months of follow-up, he was asymptomatic without signs of infection. Hybrid procedure for mycotic celiac aortic pseudoaneurysm seems to be a complementary technique to conventional open repair, especially in emergency. Endovascular approach does not preclude conversion toward conventional surgery, if necessary. This case report raises the matter of aortic endoprosthesis in infected area, the duration of suppressive antibiotherapy, and the conversion in open repair., (Copyright 2010 Annals of Vascular Surgery Inc. Published by Elsevier Inc. All rights reserved.)

We report the case of an infant 3 months old with a rare association, tetralogy of Fallot with total anomalous pulmonary veins connection the diagnosis was made by echocardiography and a successful complete reparation was achieved.

Grapevine leafroll disease (GLD) has been recognized as one of the major constraints to the production of wine grapes in Washington State. At least nine distinct Grapevine leafroll-associated viruses (GLRaV-1 to -9) have been detected in grapevines showing GLD symptoms in grape-growing areas of several countries. Previous studies documented the presence of GLRaV-1, -2, and -3 in Washington State (3). We initiated a program to test grapevine cultivars with GLD symptoms for the occurrence of the other GLRaVs. Leaf samples were collected from individual grapevines of red-berried grapevine cultivars showing typical GLD symptoms and tested by single-tube reverse transcription (RT)-PCR. Of nearly 300 samples from 13 cultivars in 19 vineyards, 14 samples from 5 cultivars (Cabernet Sauvignon, Merlot, Pinot Noir, Mourvedre, and Lagrein) in different vineyards tested positive for GLRaV-9 using primers LR9 F/F (5'-CGG CAT AAG AAA AGA TGG CAC-3') and LR9 R/R (5'-TCA TTC ACC ACT GCT TGA AC-3'), specific for the HSP-70h gene of GLRaV-9 (1). To confirm the identity of the RT-PCR products, the 393-bp amplicons obtained from each of these five cultivars were cloned individually into the pCR2.1 plasmid (Invitrogen Corp., Carlsbad, CA). Two independent clones per amplicon were sequenced from both orientations. Pairwise comparisons of these sequences (GenBank Accession Nos. EF101737, EF101738, EF101739, EF101740, and EU252530) with corresponding sequences of other GLRaVs in GenBank showed 94 to 100 and 96 to 100% identity at the nucleotide and amino acid level, respectively, with the sequence of HSP-70h gene of GLRaV-9 (GenBank Accession No. AY297819). Antiserum specific to GLRaV-9 was not accessible, therefore, an additional 540-nucleotide fragment specific to the coat protein (CP) gene of GLRaV-9 was amplified from cv. Lagrein using primers LR9-CP-F (5' TAC CGT CGA CAC TTT CGA AGC ACT 3') and LR9-CP-R (5' TGA GGC GTC GTA ACC GAA CAA TCT 3'). PCR amplified fragments were cloned and sequenced. A comparison of this sequence (GenBank Accession No. EU251512) with corresponding nucleotide sequences of other GLRaVs in GenBank showed 96% identity with CP of GLRaV-9 (GenBank Accession No. AY297819), further confirming the presence of GLRaV-9. Previously, GLRaV-9 was reported in grapevines in California (1), Tunisia (2), and Western Australia (4). To our knowledge, our results are the first evidence for the occurrence of GLRaV-9 in Washington State vineyards. Results from our study and previous reports (1,2,4) indicate the wide distribution of GLRaV-9 in several Vitis vinifera cultivars. The economic impact of GLRaV-9 on wine grape cultivars, however, remains to be determined. References: (1) R. Alkowni et al. J. Plant Pathol. 86:123, 2004. (2) N. Mahfoudhi et al. Plant Dis. 91:1359, 2007. (3) R. R. Martin et al. Plant Dis. 89:763, 2005. (4) B. K. Peake et al. Aust. Plant Pathol. 33:445, 2004.

We developed a suspension array to enhance the ability to use library-independent genetic markers for bacterial source tracking. Six markers from Enterococcus spp. were selected to distinguish between cattle, humans, and cervids. Multiplex PCR was used to amplify fecal markers and resulting products were biotinylated and fragmented by nick translation followed by hybridization to polystyrene beads. Six populations of beads were included simultaneously in each assay where beads were labeled with an oligonucleotide probe complementary to one of the six library-independent markers. Hybridized products were detected on the beads using a 2-laser flow cytometer in a 96-well format. Testing with previously characterized strains showed that the assay could achieve 100% diagnostic sensitivity and >95% diagnostic specificity. Results from water samples were congruent for conventional PCR. Serial dilutions of template DNA demonstrated that the bench top analytic sensitivity of the entire assay was equivalent to <1600 cells. Suspension arrays permit greater certainty of product identification and this format can be expanded to include many additional markers.

Washington State is the largest producer of juice grapes (Vitis labruscana 'Concord' and Vitis labrusca 'Niagara') and ranks second in wine grape production in the United States. Grapevine leafroll disease (GLD) is the most wide spread and economically significant virus disease in wine grapes in the state. Previous studies (2) have shown that Grapevine leafroll associated virus-3 (GLRaV-3) is the predominant virus associated with GLD. However, little is known about the incidence and economic impact of GLD on juice and table grapes. Because typical GLD symptoms may not be obvious among these cultivars, the prevalence and economic impact of GLD in Concord and Niagara, the most widely planted cultivars in Washington State, has received little attention from the grape and nursery industries. During the 2005 growing season, 32 samples from three vineyards and one nursery of 'Concord' and three samples from one nursery of 'Niagara' were collected randomly. Petiole extracts were tested by single-tube reverse transcription-polymerase chain reaction (RT-PCR; 3) with primers LC 1 (5'-CGC TAG GGC TGT GGA AGT ATT-3') and LC 2 (5'-GTT GTC CCG GGT ACC AGA TAT-3'), specific for the heat shock protein 70 homologue (Hsp70h gene) of GLRaV-3 (GenBank Accession No. AF037268). One 'Niagara' nursery sample and eleven 'Concord' samples from the three vineyards tested positive for GLRaV-3, producing a single band of the expected size of 546 bp. The 'Niagara' and six of the 'Concord' RT-PCR products were cloned in pCR2.1 (Invitrogen Corp, Carlsbad, CA) and the sequences (GenBank Accession Nos. DQ780885, DQ780886, DQ780887, DQ780888, DQ780889, DQ780890, and DQ780891) compared with the respective sequence of a New York isolate of GLRaV-3 (GenBank Accession No. AF037268). The analysis revealed that GLRaV-3 isolates from 'Concord' and 'Niagara' share nucleotide identities of 94 to 98% and amino acid identities and similarities of 97 to 98% with the Hsp70h gene homologue of the New York isolate of GLRaV-3. Additional testing by double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) using antibodies specific to GLRaV-3 (BIOREBA AG, Reinach, Switzerland) further confirmed these results in the 'Niagara' and two of the 'Concord' isolates. GLRaV-3 has previously been reported in labrusca cvs. Concord and Niagara in western New York (4) and Canada (1), but to our knowledge, this is the first report of GLRaV-3 in American grapevine species in the Pacific Northwest. Because wine and juice grapes are widely grown in proximity to each other in Washington State and grape mealybug (Pseudococcus maritimus), the putative vector of GLRaV-3, is present in the state vineyards, further studies will focus on the role of American grapevine species in the epidemiology of GLD. References: (1) D. J. MacKenzie et al. Plant Dis. 80:955, 1996. (2) R. R. Martin et al. Plant Dis. 89:763, 2005. (3) A. Rowhani et al. ICGV, Extended Abstracts, 13:148, 2000. (4) W. F. Wilcox et al. Plant Dis. 82:1062, 1998.

Bacterial source tracking is used to apportion fecal pollution among putative sources. Within this context, library-independent markers are genetic or phenotypic traits that can be used to identify the host origin without a need for library-dependent classification functions. The objective of this project was to use mixed-genome Enterococcus microarrays to identify library-independent markers. Separate shotgun libraries were prepared for five host groups (cow, dog, elk/deer, human, and waterfowl), using genomic DNAs (gDNAs) from ca. 50 Enterococcus isolates for each library. Microarrays were constructed (864 probes per library), and 385 comparative genomic hybridizations were used to identify putative markers. PCR assays were used to screen 95 markers against gDNAs from isolates from known sources collected throughout the United States. This validation process narrowed the selection to 15 markers, with 7 having no recognized homologues and the remaining markers being related to genes involved in metabolic pathways and DNA replication. In most cases, each marker was exclusive to one of four Enterococcus species (Enterococcus casseliflavus, E. faecalis, E. hirae, or E. mundtii). Eight markers were highly specific to either cattle, humans, or elk/deer, while the remaining seven markers were positive for various combinations of hosts other than humans. Based on microarray hybridization data, the prevalence of host-specific markers ranged from 2% to 45% of isolates collected from their respective hosts. A 20-fold difference in prevalence could present challenges for the interpretation of library-independent markers.

Flavobacterium psychrophilum is the etiological agent of bacterial coldwater disease, which causes significant problems to aquaculture worldwide. A recent study (Soule M, Cain K, LaFrentz S, Call DR [2005] Infect Immun 73:3799-3802) identified two 16S rRNA gene sequence variants (6 base differences) within the variable stem-loop region 3 for F. psychrophilum strains ATCC 49418 and CSF 259-93. That study also hypothesized that F. psychrophilum is composed of at least 2 distinct genetic lineages (I and II) described by a microarray-based comparative genomics study. In the present study, we augmented an existing 16S rDNA microarray to detect both 16S rRNA sequence variants from F. psychrophilum. Subsequent microarray experiments showed that CSF 259-93 hybridized as expected, but ATCC 49418 was positive for both sequence variants. We then developed a PCR-restriction fragment length polymorphism (RFLP) assay (MnlI and MaeIII) to distinguish between the 2 sequences. Gel isolation of PCR-RFLP products, cloning, and sequencing confirmed that ATCC 49418 harbors both 16S rRNA sequences. Microarray experiments showed that 11 of 14 strains from genetic Lineage I harbor both the CSF 259-93 and ATCC 49418 16S rRNA sequence variants, whereas all 15 Lineage II strains were only positive for the CSF 259-93 sequence (p < 0.0001). Elastin hydrolysis and tetracycline resistance were most closely associated with the latter strains (p < 0.0001 and p = 0.024, respectively). These data support the hypothesis that F. psychrophilum is composed of at least 2 distinct genetic lineages that are closely associated with host origin.

Unlabelled: Different congenital or acquired diseases increase the right ventricular systolic pressure. The elevation is achieved by pulmonary artery banding with linen tape or hydraulic devices. We introduce a new hydraulic device to be used in experimental subjects of less than 15 kilograms., Methods: An experimental laboratory phase was conducted. In this phase, the hydraulic devices were tested against pressures as high as 80 mm Hg; later on the hydraulic devices were placed on the dogs' main pulmonary artery; the right ventricular systolic pressure, pulmonary artery pressure, and their differences were obtained. The values are expressed in average +/- standard deviation., Results: The average weight of the dogs was 12.6 +/- 2.2 kg. The average diameter found in the main pulmonary artery was 12.4 +/- 1.4 mm and 27.5 +/- 1.6 mm length. Right ventricular systolic pressure of basal condition to maximum pressure obtained was 25.5 +/- 1.9 mm Hg vs 50.3 +/- 6.9 mm Hg, p < 0.0001; pulmonary artery pressures under the same conditions were 24.7 +/- 2 mm Hg vs 21.5 +/- 6.9 mm Hg, p < 0.043; and the differences between them were 0.8 +/- 1.4 mm Hg vs 28.8 +/- 4.2 mm Hg, p < 0.0001, developed by the hydraulic device respectively., Conclusions: The hydraulic device allows attaining a controlled acute increase in right ventricular systolic pressure.

Reciprocal subtractive libraries were prepared for two strains of Flavobacterium psychrophilum, one virulent and the other avirulent in a trout challenge model. Unique clones were sequenced and their distribution assessed among 34 strains. The analysis showed that F. psychrophilum is composed of two genetic lineages, possibly reflecting host specificity.

Two seven-gene phenazine biosynthetic loci were cloned from Pseudomonas aeruginosa PAO1. The operons, designated phzA1B1C1D1E1F1G1 and phzA2B2C2D2E2F2G2, are homologous to previously studied phenazine biosynthetic operons from Pseudomonas fluorescens and Pseudomonas aureofaciens. Functional studies of phenazine-nonproducing strains of fluorescent pseudomonads indicated that each of the biosynthetic operons from P. aeruginosa is sufficient for production of a single compound, phenazine-1-carboxylic acid (PCA). Subsequent conversion of PCA to pyocyanin is mediated in P. aeruginosa by two novel phenazine-modifying genes, phzM and phzS, which encode putative phenazine-specific methyltransferase and flavin-containing monooxygenase, respectively. Expression of phzS alone in Escherichia coli or in enzymes, pyocyanin-nonproducing P. fluorescens resulted in conversion of PCA to 1-hydroxyphenazine. P. aeruginosa with insertionally inactivated phzM or phzS developed pyocyanin-deficient phenotypes. A third phenazine-modifying gene, phzH, which has a homologue in Pseudomonas chlororaphis, also was identified and was shown to control synthesis of phenazine-1-carboxamide from PCA in P. aeruginosa PAO1. Our results suggest that there is a complex pyocyanin biosynthetic pathway in P. aeruginosa consisting of two core loci responsible for synthesis of PCA and three additional genes encoding unique enzymes involved in the conversion of PCA to pyocyanin, 1-hydroxyphenazine, and phenazine-1-carboxamide.