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2.
Transfusion ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38966907

RESUMO

BACKGROUND: In December 2021, the U.S. Food and Drug Administration published a letter to clinical laboratory staff and healthcare providers detailing a risk of false Rapid Plasma Reagin (RPR) when using the Bio-Rad Laboratories BioPlex 2200 Syphilis Total & RPR kit in people who had received COVID-19 vaccination; Treponema pallidum particle agglutination assays did not appear to be impacted by this issue. We evaluated reactivity rates of syphilis screening with negative confirmatory testing at our institution by year and seasonality. METHODS: We performed a retrospective study of routine syphilis testing of whole blood (WB) collections at an academic hospital-based donor center in the eastern United States. All WB donations from 2011 to 2023 which demonstrated reactive syphilis screening (Beckman Coulter PK TP Microhemagglutination) with negative confirmatory testing (CAPTIA Syphilis (T. pallidum)-G) were evaluated. Reactivity rates by year and season of donation were compared using unpaired t-tests. RESULTS: A total of 109 WB donations from 86 unique donors who donated from 2011 to 2023 screened reactive for syphilis with negative confirmatory testing. The unconfirmed syphilis reactivity rate increased from 2018 to 2023 (mean: 0.360%) compared to 2011-2017 (mean: 0.071%, p < .05). An autumnal peak in unconfirmed reactives was observed. CONCLUSION: The unconfirmed syphilis reactivity rate among WB donors at our institution increased markedly since 2017 compared to the 7 years prior and doubled from 2020 to 2021. No testing assay changes explain these results. The autumnal peak in unconfirmed reactives suggests a possible environmental trigger such as viral infection or vaccination.

3.
N Engl J Med ; 391(3): 213-223, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39018531

RESUMO

BACKGROUND: The efficacy and safety of risankizumab as compared with ustekinumab in patients with Crohn's disease are unknown. METHODS: In this phase 3b, multicenter, open-label, randomized, controlled trial with blinded assessment of end points, patients with moderate-to-severe Crohn's disease who had had an inadequate response to anti-tumor necrosis factor (TNF) therapy or unacceptable side effects with such therapy were randomly assigned to receive risankizumab or ustekinumab at standard doses for 48 weeks. The two primary end points, which were tested sequentially, were clinical remission at week 24 (defined as a Crohn's Disease Activity Index score of <150 [range, 0 to 600, with higher scores indicating more severe disease activity]), which was analyzed in the first 50% of patients to complete the week 24 visit, with a noninferiority margin of 10 percentage points; and endoscopic remission at week 48 (defined as a score of ≤4, a decrease of ≥2 points from baseline, and no subscore >1 in any individual variable on the Simple Endoscopic Score for Crohn's Disease [range, 0 to 56, with higher scores indicating more severe disease]), which was analyzed for superiority in 100% of the patients. Safety was assessed in all patients who received at least one dose of risankizumab or ustekinumab. RESULTS: In the full intention-to-treat population for the efficacy analysis, 230 of 255 patients (90.2%) who received risankizumab and 193 of 265 patients (72.8%) who received ustekinumab completed all the assigned treatments. Both primary end points were met; risankizumab was noninferior to ustekinumab with respect to clinical remission at week 24 (58.6% vs. 39.5%; adjusted difference, 18.4 percentage points; 95% confidence interval [CI], 6.6 to 30.3) and superior to ustekinumab with respect to endoscopic remission at week 48 (31.8% vs. 16.2%; adjusted difference, 15.6 percentage points; 95% CI, 8.4 to 22.9; P<0.001). The incidence of adverse events appeared to be similar in the two groups. CONCLUSIONS: In this head-to-head clinical trial of risankizumab and ustekinumab involving patients with moderate-to-severe Crohn's disease who had had unacceptable side effects with anti-TNF therapy or an inadequate response to such therapy, risankizumab was noninferior to ustekinumab with respect to clinical remission at week 24 and superior with respect to endoscopic remission at week 48. (Funded by AbbVie; ClinicalTrials.gov number, NCT04524611.).


Assuntos
Anticorpos Monoclonais , Doença de Crohn , Indução de Remissão , Ustekinumab , Humanos , Doença de Crohn/tratamento farmacológico , Ustekinumab/uso terapêutico , Ustekinumab/efeitos adversos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais/efeitos adversos , Índice de Gravidade de Doença , Análise de Intenção de Tratamento , Adulto Jovem
5.
Proc Natl Acad Sci U S A ; 121(30): e2400425121, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39012818

RESUMO

In the centuries following Christopher Columbus's 1492 voyage to the Americas, transoceanic travel opened unprecedented pathways in global pathogen circulation. Yet no biological transfer is a single, discrete event. We use mathematical modeling to quantify historical risk of shipborne pathogen introduction, exploring the respective contributions of journey time, ship size, population susceptibility, transmission intensity, density dependence, and pathogen biology. We contextualize our results using port arrivals data from San Francisco, 1850 to 1852, and from a selection of historically significant voyages, 1492 to 1918. We offer numerical estimates of introduction risk across historically realistic ranges of journey time and ship population size, and show that both steam travel and shipping regimes that involved frequent, large-scale movement of people substantially increased risk of transoceanic pathogen circulation.


Assuntos
Navios , Viagem , Humanos , Vapor , Modelos Teóricos , São Francisco/epidemiologia , História do Século XX , História do Século XIX
6.
Eur Radiol Exp ; 8(1): 76, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38981998

RESUMO

BACKGROUND: Clinical imaging tools to probe aggressiveness of renal masses are lacking, and T2-weighted imaging as an integral part of magnetic resonance imaging protocol only provides qualitative information. We developed high-resolution and accelerated T2 mapping methods based on echo merging and using k-t undersampling and reduced flip angles (TEMPURA) and tested their potential to quantify differences between renal tumour subtypes and grades. METHODS: Twenty-four patients with treatment-naïve renal tumours were imaged: seven renal oncocytomas (RO); one eosinophilic/oncocytic renal cell carcinoma; two chromophobe RCCs (chRCC); three papillary RCCs (pRCC); and twelve clear cell RCCs (ccRCC). Median, kurtosis, and skewness of T2 were quantified in tumours and in the normal-adjacent kidney cortex and were compared across renal tumour subtypes and between ccRCC grades. RESULTS: High-resolution TEMPURA depicted the tumour structure at improved resolution compared to conventional T2-weighted imaging. The lowest median T2 values were present in pRCC (high-resolution, 51 ms; accelerated, 45 ms), which was significantly lower than RO (high-resolution; accelerated, p = 0.012) and ccRCC (high-resolution, p = 0.019; accelerated, p = 0.008). ROs showed the lowest kurtosis (high-resolution, 3.4; accelerated, 4.0), suggestive of low intratumoural heterogeneity. Lower T2 values were observed in higher compared to lower grade ccRCCs (grades 2, 3 and 4 on high-resolution, 209 ms, 151 ms, and 106 ms; on accelerated, 172 ms, 160 ms, and 102 ms, respectively), with accelerated TEMPURA showing statistical significance in comparison (p = 0.037). CONCLUSIONS: Both high-resolution and accelerated TEMPURA showed marked potential to quantify differences across renal tumour subtypes and between ccRCC grades. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03741426 . Registered on 13 November 2018. RELEVANCE STATEMENT: The newly developed T2 mapping methods have improved resolution, shorter acquisition times, and promising quantifiable readouts to characterise incidental renal masses.


Assuntos
Neoplasias Renais , Imageamento por Ressonância Magnética , Gradação de Tumores , Humanos , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/classificação , Neoplasias Renais/patologia , Imageamento por Ressonância Magnética/métodos , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Carcinoma de Células Renais/diagnóstico por imagem , Carcinoma de Células Renais/classificação , Carcinoma de Células Renais/patologia , Adulto
7.
Res Sq ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38978570

RESUMO

Purpose: Glypican-3 (GPC3)-targeted radioisotope immuno-positron emission tomography (immunoPET) may lead to earlier and more accurate diagnosis of hepatocellular carcinoma (HCC), thus facilitating curative treatment, decreasing early recurrence, and enhancing patient survival. We previously demonstrated reliable HCC detection using a zirconium-89-labeled murine anti-GPC3 antibody (89Zr-αGPC3M) for immunoPET. This study evaluated the efficacy of the humanized antibody successor (αGPC3H) to further clinical translation of a GPC3-based theranostic for HCC. Methods: In vitro αGPC3 binding to HepG2 cells was assessed by flow cytometry. In vivo 89Zr-αGPC3H and 89Zr-αGPC3M tumor uptake was evaluated by PET/CT and biodistribution studies in an orthotopic xenograft mouse model of HCC. Results: αGPC3H maintained binding to GPC3 in vitro and 89Zr-αGPC3H immunoPET identified liver tumors in vivo. PET/CT and biodistribution analyses demonstrated high 89Zr-αGPC3H tumor uptake and tumor-to-liver ratios, with no difference between groups. Conclusion: Humanized αGPC3 successfully targeted GPC3 in vitro and in vivo. 89Zr-αGPC3H immunoPET had comparable tumor detection to 89Zr-αGPC3M, with highly specific tumor uptake, making it a promising strategy to improve HCC detection.

8.
HPB (Oxford) ; 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38971667

RESUMO

BACKGROUND: Postoperative pancreatic fistulas lead to substantially increased morbidity, mortality, and healthcare costs after pancreatectomy. Studies have reported conflicting data on the role of prophylactic somatostatin analogs in the reduction of postoperative pancreatic fistula. Current practice patterns, surgeon beliefs, and barriers to using these drugs in the Americas is not known. METHODS: An online 26-question cross-sectional survey was distributed via email to the members of the Americas Hepato-Pancreato-Biliary Association in April 2023. RESULTS: One hundred and two surgeons responded in spring 2023. 48.0% of respondents reported using prophylactic SSAs during their surgical training, however, only 29.4% do so in their current practice, most commonly when performing Whipple procedures. Octreotide was the most frequently used SSA (34.3%), followed by octreotide LAR (12.7%) and pasireotide (11.8%). Reasons for not prescribing included a lack of high-quality data (62.7%), perception of limited efficacy (34.3%) and high cost (30.4%). CONCLUSION: These results highlight key areas for future study including understanding surgeon rationale for patient and drug selection. Variable practice patterns amongst surgeons also underscore the importance of generalizability in the design of future clinical trials in order to maximize impact.

9.
J Gen Virol ; 105(7)2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39045787

RESUMO

Domestic dogs (Canis lupus familiaris) live with humans, frequently contact other animals and may serve as intermediary hosts for the transmission of viruses. Free-roaming dogs, which account for over 70% of the world's domestic dog population, may pose a particularly high risk in this regard. We conducted an epidemiological study of dog viromes in three locations in Uganda, representing low, medium and high rates of contact with wildlife, ranging from dogs owned specifically for traditional hunting in a biodiversity and disease 'hotspot' to pets in an affluent suburb. We quantified rates of contact between dogs and wildlife through owner interviews and conducted canine veterinary health assessments. We then applied broad-spectrum viral metagenomics to blood plasma samples, from which we identified 46 viruses, 44 of which were previously undescribed, in three viral families, Sedoreoviridae, Parvoviridae and Anelloviridae. All 46 viruses (100 %) occurred in the high-contact population of dogs compared to 63 % and 39 % in the medium- and low-contact populations, respectively. Viral prevalence ranged from 2.1 % to 92.0 % among viruses and was highest, on average, in the high-contact population (22.3 %), followed by the medium-contact (12.3 %) and low-contact (4.8 %) populations. Viral richness (number of viruses per dog) ranged from 0 to 27 and was markedly higher, on average, in the high-contact population (10.2) than in the medium-contact (5.7) or low-contact (2.3) populations. Viral richness was strongly positively correlated with the number of times per year that a dog was fed wildlife and negatively correlated with the body condition score, body temperature and packed cell volume. Viral abundance (cumulative normalized metagenomic read density) varied 124-fold among dogs and was, on average, 4.1-fold higher and 2.4-fold higher in the high-contact population of dogs than in the low-contact or medium-contact populations, respectively. Viral abundance was also strongly positively correlated with the number of times per year that a dog was fed wildlife, negatively correlated with packed cell volume and positively correlated with white blood cell count. These trends were driven by nine viruses in the family Anelloviridae, genus Thetatorquevirus, and by one novel virus in the family Sedoreoviridae, genus Orbivirus. The genus Orbivirus contains zoonotic viruses and viruses that dogs can acquire through ingestion of infected meat. Overall, our findings show that viral prevalence, richness and abundance increased across a gradient of contact between dogs and wildlife and that the health status of the dog modified viral infection. Other ecological, geographic and social factors may also have contributed to these trends. Our finding of a novel orbivirus in dogs with high wildlife contact supports the idea that free-roaming dogs may serve as intermediary hosts for viruses of medical importance to humans and other animals.


Assuntos
Animais Selvagens , Doenças do Cão , Animais , Cães , Uganda/epidemiologia , Doenças do Cão/virologia , Doenças do Cão/epidemiologia , Doenças do Cão/transmissão , Prevalência , Animais Selvagens/virologia , Viroma , Vírus/classificação , Vírus/isolamento & purificação , Vírus/genética , Metagenômica , Anelloviridae/genética , Anelloviridae/isolamento & purificação , Anelloviridae/classificação , Humanos , Viroses/epidemiologia , Viroses/veterinária , Viroses/transmissão , Viroses/virologia
10.
J Surg Oncol ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38990255

RESUMO

BACKGROUND AND OBJECTIVES: Few data exist to guide optimal communication practices for surgical oncologists. VitalTalk, an evidence-based communication skills training model for clinicians, offers the five-step ADAPT tool for discussing prognosis. This study aimed to characterize surgeon communication of pancreatic cancer prognosis using VitalTalk's ADAPT framework. METHODS: Contemporaneous audio recordings from 12 initial surgeon-patient encounters for borderline resectable pancreatic cancer were transcribed. Directed qualitative content analysis based on ADAPT (Ask, Discover, Anticipate, Provide, and Track) was used to deductively code transcripts. RESULTS: All encounters contained at least one ADAPT step while only one (8%) incorporated four or five steps. Surgeons provided prognostic information (Provide) in all but one encounter (92%); most was qualitative and clustered into themes: serious illness, surgical candidacy, prognostic ambiguity, and cancer recurrence. Surgeons elicited understanding (Ask), requested information preferences (Discover), anticipated ambivalence (Anticipate), and responded to emotion (Track) in a minority of encounters (25%-42%); of 15 patient emotional cues, six were not addressed by surgeons. CONCLUSIONS: During an initial encounter for pancreatic cancer, surgeons focus heavily on providing information but omit critical prognostic communication steps. Future studies are needed to investigate if surgeon training in palliative care-based communication is feasible and impacts patient-perceived quality of communication.

12.
J Orthop ; 57: 147-152, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39040566

RESUMO

Background: Although total knee replacement (TKR) surgery has succeeded in improving pain and deformity, a proportion of patients remain incompletely satisfied with their outcome. This prospective study aims to assess the survivorship, clinical, and radiological outcomes using a novel 'kinematic retaining' (KR) implant. Methods: 156 patients underwent TKR surgery for primary osteoarthritis using the Physica KR implant at three European Centres. Patients were followed up for five years using both radiographic and clinical evaluations. Results: Within 6 months post-operatively, 79.4% and 85.9% had good-excellent clinical and functional KSS values, this was maintained to 76.9% and 79.5% at five years. Mean Knee Society Score (KSS) improvement at 5 years was 32.8 (from 23 to 40) and 37.4 (from 30 to 50) (p < 0.01). All Knee Injury and Osteoarthritis Outcome Score (KOOS) sub-scores showed statistically significant improvement from before surgery at a mean of 34.7 (SD ± 16.1) to a mean of 86.6 (SD ± 16.1) at five years. The mean Oxford Knee Score (OKS) was 43.7 (±5.6), with over 80% of the patients having a good-excellent outcome at five years. OKS improved significantly by six weeks after surgery (p < 0.01) and remained constant throughout the 5-year follow-up. Visual Analogue Score (VAS) Satisfaction scores improved significantly after the post-operative time point of six weeks. From 1 year to 5 years, the average VAS was over 85 mm. The Forgotten Joint Score (FJS) increased from 64.5 at 1 year to 79.2 at 5 years after surgery (p < 0.01). No progressive adverse radiographic features were noted. Two patients were revised during the study period: one for infection and the other for aseptic loosening. Conclusions: This novel 'kinematic retaining' knee prosthesis has shown exceptional clinical and patient-reported improvements, with a remarkable 99.4% survivorship (95.5-99.9) at five years.

13.
Ann Surg ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38939972

RESUMO

OBJECTIVE: We aimed to establish global benchmark outcomes indicators for L-RPS/H67. BACKGROUND: Minimally invasive liver resections has seen an increase in uptake in recent years. Over time, challenging procedures as laparoscopic right posterior sectionectomies (L-RPS)/H67 are also increasingly adopted. METHODS: This is a post hoc analysis of a multicenter database of 854 patients undergoing minimally invasive RPS (MI-RPS) in 57 international centers in 4 continents between 2015 and 2021. There were 651 pure L-RPS and 160 robotic RPS (R-RPS). Sixteen outcome indicators of low-risk L-RPS cases were selected to establish benchmark cutoffs. The 75th percentile of individual center medians for a given outcome indicator was set as the benchmark cutoff. RESULTS: There were 573 L-RPS/H67 performed in 43 expert centers, of which 254 L-RPS/H67 (44.3%) cases qualified as low risk benchmark cases. The benchmark outcomes established for operation time, open conversion rate, blood loss ≥500 mL, blood transfusion rate, postoperative morbidity, major morbidity, 90-day mortality and textbook outcome after L-RPS were 350.8 minutes, 12.5%, 53.8%, 22.9%, 23.8%, 2.8%, 0% and 4% respectively. CONCLUSIONS: The present study established the first global benchmark values for L-RPS/H6/7. The benchmark provided an up-to-date reference of best achievable outcomes for surgical auditing and benchmarking.

17.
J Neurophysiol ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38865580

RESUMO

Saccade adaptation plays a crucial role in maintaining saccade accuracy. The behavioral characteristics and neural mechanisms of saccade adaptation for an externally cued movement, such as visually-guided saccades (VGS), are well studied in non-human primates. In contrast, little is known about the saccade adaptation of an internally driven movement, such as memory-guided saccades (MGS), which are guided by visuospatial working memory. As the oculomotor plant changes due to growth, aging, or skeletomuscular problems, both types of saccades need to be adapted. Do both saccade types engage a common adaptation mechanism? In this study, we compared the characteristics of amplitude decrease adaptation in MGS with VGS in non-human primates. We found that the adaptation speed was faster for MGS than for VGS. Saccade duration changed during MGS adaptation, while saccade peak velocity changed during VGS adaptation. We also compared the adaptation field, that is, the gain change for saccade amplitudes other than the adapted. The gain change for MGS declines on both smaller and larger sides of adapted amplitude, more rapidly for larger than smaller amplitudes, while the decline in VGS was reversed. Thus, the differences between VGS and MGS adaptation characteristics support the previously suggested hypothesis that the adaptation mechanisms of VGS and MGS are distinct. Furthermore, the result suggests that the MGS adaptation site is a brain structure that influences saccade duration, while the VGS adaptation site influences saccade peak velocity. These results should be beneficial for future neurophysiological experiments.

18.
Ann Surg Oncol ; 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38879668

RESUMO

INTRODUCTION: Despite the increasing widespread adoption and experience in minimally invasive liver resections (MILR), open conversion occurs not uncommonly even with minor resections and as been reported to be associated with inferior outcomes. We aimed to identify risk factors for and outcomes of open conversion in patients undergoing minor hepatectomies. We also studied the impact of approach (laparoscopic or robotic) on outcomes. METHODS: This is a post-hoc analysis of 20,019 patients who underwent RLR and LLR across 50 international centers between 2004-2020. Risk factors for and perioperative outcomes of open conversion were analysed. Multivariate and propensity score-matched analysis were performed to control for confounding factors. RESULTS: Finally, 10,541 patients undergoing either laparoscopic (LLR; 89.1%) or robotic (RLR; 10.9%) minor liver resections (wedge resections, segmentectomies) were included. Multivariate analysis identified LLR, earlier period of MILR, malignant pathology, cirrhosis, portal hypertension, previous abdominal surgery, larger tumor size, and posterosuperior location as significant independent predictors of open conversion. The most common reason for conversion was technical issues (44.7%), followed by bleeding (27.2%), and oncological reasons (22.3%). After propensity score matching (PSM) of baseline characteristics, patients requiring open conversion had poorer outcomes compared with successful MILR cases as evidenced by longer operative times, more blood loss, higher requirement for perioperative transfusion, longer duration of hospitalization and higher morbidity, reoperation, and 90-day mortality rates. CONCLUSIONS: Multiple risk factors were associated with conversion of MILR even for minor hepatectomies, and open conversion was associated with significantly poorer perioperative outcomes.

19.
Discov Immunol ; 3(1): kyae008, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38903247

RESUMO

Direct interaction between T-cells exerts a major influence on tissue immunity and inflammation across multiple body sites including the human gut, which is highly enriched in 'unconventional' lymphocytes such as γδ T-cells. We previously reported that microbial activation of human Vγ9/Vδ2+ γδ T-cells in the presence of the mucosal damage-associated cytokine IL-15 confers the ability to promote epithelial barrier defence, specifically via induction of IL-22 expression in conventional CD4+ T-cells. In the current report, we assessed whether other cytokines enriched in the gut milieu also functionally influence microbe-responsive Vγ9/Vδ2 T-cells. When cultured in the presence of IL-21, Vγ9/Vδ2 T-cells acquired the ability to induce expression of the immunoregulatory cytokine IL-10 in both naïve and memory CD4+ T-cells, at levels surpassing those induced by monocytes or monocyte-derived DCs. These findings identify an unexpected influence of IL-21 on Vγ9/Vδ2 T-cell modulation of CD4+ T-cell responses. Further analyses suggested a possible role for CD30L and/or CD40L reverse signalling in mediating IL-10 induction by IL-21 conditioned Vγ9/Vδ2 T-cells. Our findings indicate that the local microenvironment exerts a profound influence on Vγ9/Vδ2 T-cell responses to microbial challenge, leading to induction of distinct functional profiles among CD4+ T-cells that may influence inflammatory events at mucosal surfaces. Targeting these novel pathways may offer therapeutic benefit in disorders such as inflammatory bowel disease.

20.
BMC Vet Res ; 20(1): 266, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38902706

RESUMO

BACKGROUND: Pathogenic Leptospira species are globally important zoonotic pathogens capable of infecting a wide range of host species. In marine mammals, reports of Leptospira have predominantly been in pinnipeds, with isolated reports of infections in cetaceans. CASE PRESENTATION: On 28 June 2021, a 150.5 cm long female, short-beaked common dolphin (Delphinus delphis delphis) stranded alive on the coast of southern California and subsequently died. Gross necropsy revealed multifocal cortical pallor within the reniculi of the kidney, and lymphoplasmacytic tubulointerstitial nephritis was observed histologically. Immunohistochemistry confirmed Leptospira infection, and PCR followed by lfb1 gene amplicon sequencing suggested that the infecting organism was L.kirschneri. Leptospira DNA capture and enrichment allowed for whole-genome sequencing to be conducted. Phylogenetic analyses confirmed the causative agent was a previously undescribed, divergent lineage of L.kirschneri. CONCLUSIONS: We report the first detection of pathogenic Leptospira in a short-beaked common dolphin, and the first detection in any cetacean in the northeastern Pacific Ocean. Renal lesions were consistent with leptospirosis in other host species, including marine mammals, and were the most significant lesions detected overall, suggesting leptospirosis as the likely cause of death. We identified the cause of the infection as L.kirschneri, a species detected only once before in a marine mammal - a northern elephant seal (Mirounga angustirostris) of the northeastern Pacific. These findings raise questions about the mechanism of transmission, given the obligate marine lifestyle of cetaceans (in contrast to pinnipeds, which spend time on land) and the commonly accepted view that Leptospira are quickly killed by salt water. They also raise important questions regarding the source of infection, and whether it arose from transmission among marine mammals or from terrestrial-to-marine spillover. Moving forward, surveillance and sampling must be expanded to better understand the extent to which Leptospira infections occur in the marine ecosystem and possible epidemiological linkages between and among marine and terrestrial host species. Generating Leptospira genomes from different host species will yield crucial information about possible transmission links, and our study highlights the power of new techniques such as DNA enrichment to illuminate the complex ecology of this important zoonotic pathogen.


Assuntos
Leptospira , Leptospirose , Animais , Leptospira/isolamento & purificação , Leptospira/genética , Leptospira/classificação , Leptospirose/veterinária , Leptospirose/microbiologia , Leptospirose/epidemiologia , California/epidemiologia , Feminino , Filogenia , Golfinhos Comuns/microbiologia
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