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Pseudo-nitzschia is a cosmopolitan genus, some species of which can produce domoic acid (DA), a neurotoxin responsible for the Amnesic Shellfish Poisoning (ASP). In this study, we identified P. subpacifica for the first time in Todos Santos Bay and Manzanillo Bay, in the Mexican Pacific using SEM and molecular methods. Isolates from Todos Santos Bay were cultivated under conditions of phosphate sufficiency and deficiency at 16°C and 22°C to evaluate the production of DA. This toxin was detected in the particulate (DAp) and dissolved (DAd) fractions of the cultures during the exponential and stationary phases of growth of the cultures. The highest DA concentration was detected during the exponential phase grown in cells maintained in P-deficient medium at 16°C (1.14 ± 0.08 ng mL-1 DAd and 4.71 ± 1.11 × 10-5 ng cell-1 of DAp). In P-sufficient cultures DA was higher in cells maintained at 16°C (0.25 ± 0.05 ng mL-1 DAd and 9.41 ± 1.23 × 10-7 ng cell-1 of DAp) than in cells cultured at 22°C. Therefore, we confirm that P. subpacifica can produce DA, especially under P-limited conditions that could be associated with extraordinary oceanographic events such as the 2013-2016 "Blob" in the northeastern Pacific Ocean. This event altered local oceanographic conditions and possibly generated the presence of potential harmful species in areas with economic importance on the Mexican Pacific coast.

The response of primary producers to seasonal and interannual variabilities in the hydrographic conditions observed between 1997 and 2012 is analyzed for the southern portion of the California Current System (CCS). The analysis uses the optimum rate of primary productivity (PP) normalized by units of chlorophyll (Chla) in the water column (PBopt) and Chla concentration. In situ PP estimations using the 14C method were obtained as part of the seasonal cruises conducted by the Investigaciones Mexicanas de la Corriente de California program. Supplementary data included sea surface temperature (SST) as measured by the AVHRR sensor from 1985–2009. We found the mean value of PBopt to be at 5.1 ± 3.3 mg C·(mg Chla)–1·h–1, with maximum ranges of 0.5 and 17.5 mg C·(mg Chla)–1·h–1. The relationship between PBopt and SST suggested a phytoplankton community change at around 19 ºC, which characterized the transitional nature of the southern portion of the CCS. SST data suggested, on the one hand, that on average the 19 ºC isotherm is located in the vicinity of Punta Eugenia and, on the other, that its spatial variability defined the alternating cool–warm conditions. At the seasonal scale, this isotherm showed a marked latitudinal displacement (from 24ºN to 32ºN), which was observed to be even out of this range during interannual events associated with El Niño/La Niña. Under both cool-warm hydrographic conditions, the phytoplanktonic community showed large PBopt rates (~6 mg C·(mg Chla)–1·h–1). At the interannual scale, changes were associated to changes in the abundance and composition of nano-microphytoplankton. Additionally, data suggested that high PP rates during warm periods could be attributed to an enhanced picoplankton contribution.

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Purpose: To compare four diffusion-weighted imaging (DWI) sequences for image quality, rectal contour, and lesion conspicuity, and to assess the difference in their signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR), and apparent diffusion coefficient (ADC). Methods: In this retrospective study of 36 consecutive patients who underwent 3.0 T rectal MRI from January–June 2020, DWI was performed with single-shot echo planar imaging (ss-EPI) (b800 s/mm2), multiplexed sensitivity encoding (MUSE) (b800 s/mm2), MUSE (b1500 s/mm2), and field-of-view optimized and constrained undistorted single-shot (FOCUS) (b1500 s/mm2). Two radiologists independently scored image quality using a 5-point Likert scale. Inter-reader agreement was assessed using the weighted Cohen's к. SNR, CNR, and ADC measurements were compared using the paired t-test. Results: For both readers, MUSE b800 scored significantly higher for image quality, rectal contour, and lesion conspicuity compared to ss-EPI; MUSE b800 also scored significantly higher for image quality and rectal contour compared to all other sequences. Lesion conspicuity was equally superior for MUSE b800 and MUSE b1500 compared to the other two sequences. There was good to excellent inter-reader agreement for all qualitative features (к = 0.72–0.88). MUSE b800 had the highest SNR; MUSE b1500 had the highest CNR. A significant difference in ADC was observed between ss-EPI compared to the other sequences (p < 0.001) and between MUSE b800 and FOCUS. No significant difference in ADC was found between MUSE b1500 and FOCUS b1500. Conclusion: MUSE b800 improved image quality over ss-EPI and both MUSE b800 and b1500 showed better tumor conspicuity compared to conventional ss-EPI. [ABSTRACT FROM AUTHOR]

Orthohantaviruses (genus Orthohantavirus, family Hantaviridae) are the etiologic agents of Hantavirus Pulmonary Syndrome in the Americas. In South America, orthohantaviruses are highly diverse and are hosted by sigmodontine rodents (subfamiliy Sigmodontinae, family Cricetidae), an also diverse group of rodents. The aims of this work were to (1) identify orthohantavirus hosts and (2) to study the spatial and temporal variations in the prevalence of infection and their associations with community, environmental and individual characteristics, in different environments of Misiones province, northeastern Argentina. Live-capture sessions were carried out during two years in different land uses, with a trapping effort of 31,653 trap nights. We captured 719 individuals from the species Akodon montensis, Rattus rattus, Mus musculus, Calomys tener, Thaptomys nigrita, Oligoryzomys nigripes, Euryoryzomys russatus, Oligoryzomys flavescens, Brucepattersonius sp., and Juliomys pictipes. Antibodies against orthohantavirus were detected in Akodon montensis in one natural protected and one periurban areas, and it was the most abundant species in almost every study sites. We observed the presence of spatial focality of orthohantavirus infection and a positive association with host abundance suggesting the existence of a threshold density. At the individual level, large, reproductively active, and male individuals were more likely to have antibodies against orthohantavirus. This is the first record of orthohantavirus infection in A. montensis in Argentina, which shows the importance of investigations about emerging diseases. [ABSTRACT FROM AUTHOR]

Pseudo-nitzschia is a cosmopolitan genus, some species of which can produce domoic acid (DA), a neurotoxin responsible for the Amnesic Shellfish Poisoning (ASP). In this study, we identified P. subpacifica for the first time in Todos Santos Bay and Manzanillo Bay, in the Mexican Pacific using SEM and molecular methods. Isolates from Todos Santos Bay were cultivated under conditions of phosphate sufficiency and deficiency at 16°C and 22°C to evaluate the production of DA. This toxin was detected in the particulate (DAp) and dissolved (DAd) fractions of the cultures during the exponential and stationary phases of growth of the cultures. The highest DA concentration was detected during the exponential phase grown in cells maintained in P-deficient medium at 16°C (1.14 ± 0.08 ng mL-1 DAd and 4.71 ± 1.11 × 10−5 ng cell-1 of DAp). In P-sufficient cultures DA was higher in cells maintained at 16°C (0.25 ± 0.05 ng mL-1 DAd and 9.41 ± 1.23 × 10−7 ng cell-1 of DAp) than in cells cultured at 22°C. Therefore, we confirm that P. subpacifica can produce DA, especially under P-limited conditions that could be associated with extraordinary oceanographic events such as the 2013–2016 "Blob" in the northeastern Pacific Ocean. This event altered local oceanographic conditions and possibly generated the presence of potential harmful species in areas with economic importance on the Mexican Pacific coast. [ABSTRACT FROM AUTHOR]

Purpose: To assess the associations between inter-site texture heterogeneity parameters derived from computed tomography (CT), survival, and BRCA mutation status in women with high-grade serous ovarian cancer (HGSOC). Materials and methods: Retrospective study of 88 HGSOC patients undergoing CT and BRCA mutation status testing prior to primary cytoreductive surgery. Associations between texture metrics—namely inter-site cluster variance (SCV), inter-site cluster prominence (SCP), inter-site cluster entropy (SE)—and overall survival (OS), progression-free survival (PFS) as well as BRCA mutation status were assessed. Results: Higher inter-site cluster variance (SCV) was associated with lower PFS (p = 0.006) and OS (p = 0.003). Higher inter-site cluster prominence (SCP) was associated with lower PFS (p = 0.02) and higher inter-site cluster entropy (SE) correlated with lower OS (p = 0.01). Higher values of all three metrics were significantly associated with lower complete surgical resection status in BRCA-negative patients (SE p = 0.039, SCV p = 0.006, SCP p = 0.02), but not in BRCA-positive patients (SE p = 0.7, SCV p = 0.91, SCP p = 0.67). None of the metrics were able to distinguish between BRCA mutation carrier and non-mutation carrier. Conclusion: The assessment of tumoral heterogeneity in the era of personalized medicine is important, as increased heterogeneity has been associated with distinct genomic abnormalities and worse patient outcomes. A radiomics approach using standard-of-care CT scans might have a clinical impact by offering a non-invasive tool to predict outcome and therefore improving treatment effectiveness. However, it was not able to assess BRCA mutation status in women with HGSOC. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of our study was to retrospectively evaluate and categorize temporal changes in MRI appearances of the prostate in patients who underwent focal therapy with MRI follow-up.Methods: The Institutional Review Board approved this retrospective study and waived the requirement for informed consent. Thirty-seven patients (median age 61; 48-70 years) with low-to-intermediate-risk, clinically organ-confined prostate cancer underwent focal ablation therapy from 2009 to 2014. Two radiologists reviewed post-treatment MRIs (n = 76) and categorized imaging features blinded to the time interval between the focal therapy and the follow-up MRI. Inter-reader agreement was assessed (kappa) and generalized linear regression was used to examine associations between an imaging feature being present/absent and days between ablation and MRI.Results: Inter-reader agreement on MRI features ranged from fair to substantial. Edema was found present at earlier times after ablation (median 16-25 days compared to MRIs without edema, median 252-514 days), as was rim enhancement of the ablation zone (18-22.5 days vs. 409-593 days), a hypointense rim around the ablation zone on T2-weighted images (53-57.5 days vs. 279-409 days) and the presence of an appreciable ablation cavity (48.5-60 days vs. 613-798 days, all p < 0.05). Enhancement of the ablation zone/scar (553-731 days vs. 61.5-162 days) and the formation of a T2-hypointense scar were found to be present on later MRI scans (514-553 days vs. 29-32 days, one reader).Conclusions: The MRI appearance of the prostate after focal ablation changes substantially over time. Identification of temporal patterns in the appearance of imaging features should help reduce image interpretation variability and errors when assessing post-therapeutic scans. [ABSTRACT FROM AUTHOR]

This article is based on original archival research (The State Archive of Russian Federation and The Foreign Policy Archive of the Russian Federation) and is dedicated to a donation process that took place in the period 1945-1949 when a collection of modern Mexican art was given to the Soviet state. The story behind this donation process was discovered by the author in 2016 and has never been published or mentioned by scholars before. In 1943, the Soviet ambassador to Mexico Konstantin Umansky had the idea to introduce Mexican visual arts to the Soviet public by donating works of the Mexican contemporary artists. Two institutions were involved in this process: "The Institute of Mexican- Russian cultural exchange" (MRI) as a sending party and the "All-Union Society for Cultural Relations with Foreign " (VOKS) as a receiving party. Preparations and letter correspondence took about two years until finally, the donation arrived in the Soviet Union in December 1947. Though the Soviet officials were involved in the process, in Moscow nearly all of the works were declared to be "formalistic and surrealist" and therefore not suitable for public display. Since the 1950s this unique, but eventually unwanted gift has been reported as lost. Reconstructing all the steps of the process and locating every artwork still has to be done. [ABSTRACT FROM AUTHOR]

The Garifuna people of Trujillo, Honduras, wryly call it la maldición—the curse. Despite the expansive resources of the area and the sheer amount of valuable commodities that have left from its shores, most of the local people remain poor, with little access to sanitation, reliable electricity, literacy, security, or employment. This study explores the ways in which private tourism development projects conspire with national and international politics and economics to perpetuate la maldición. An analysis of 40 qualitative interviews, three focus groups, and survey data from the Trujillo area is combined with secondary historical, economic, and political data regarding the national and international processes in which local dynamics are embedded. Although past research has shown it to be possible for development projects to be designed in a way that benefits indigenous populations, in the case of Trujillo, Honduras, macroimperial, mesoimperial and microimperial processes conspire to assure that such projects exploit and marginalize instead of include and benefit local people. [ABSTRACT FROM AUTHOR]

Objective: To determine the etiologies of myonecrosis in oncology patients and to assess interobserver variability in interpreting its MRI features.Materials and Methods: Pathology records in our tertiary cancer hospital were searched for proven myonecrosis, and MRIs of affected regions in those patients were identified. MRI reports that suggested myonecrosis were also identified. Each MRI was reviewed independently by 2 out of 6 readers to assess anatomical site, size, and signal intensities of muscle changes, and the presence of the previously reported stipple sign (enhancing foci within a region defined by rim enhancement). The stipple sign was assessed again, weeks after a training session. Cohen kappa and percentage agreement were calculated. Medical records were reviewed for contemporaneous causes of myonecrosis.Results: MRI reports in 73 patients suggested the diagnosis of myonecrosis; pathological proof was available in another 2. Myonecrosis was frequently associated with radiotherapy (n = 34 patients, 45 %); less frequent causes included intraoperative immobilization, trauma, therapeutic embolization, ablation therapy, exercise, and diabetes. Myonecrosis usually involved the lower extremity, the pelvis, and the upper extremity; mean size was 13.0 cm. The stipple sign was observed in 55-100 % of patients at first assessment (κ = 0.09-0.42; 60-80 % agreement) and 55-100 % at second (κ = 0.0-0.58; 72-90 % agreement). Enhancement surrounded myonecrosis in 55-100 % patients (κ = 0.03-0.32; 58-70 % agreement).Conclusion: Myonecrosis in oncology patients usually occurred after radiotherapy, and less commonly after intraoperative immobilization, trauma, therapeutic embolization, ablation therapy, exercise, or diabetes. Although interobserver variability for MRI features of myonecrosis exists (even after focused training), a combination of findings facilitates diagnosis and conservative management. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of the study was to assess the inter-observer agreement on the qualitative and quantitative evaluation of relative signal intensity of liver lesions on delayed hepatobiliary phase (HBP) MRI with gadoxetate (Gd-EOB-DTPA). Methods: 105 patients with liver lesions, who had delayed HPB MRI using gadoxetate were reviewed retrospectively. For each patient, four readers (two fellows in training and two attending radiologists) qualitatively assessed the relative SI of the largest representative lesion on a five point scale, and quantitatively measured the relative SI of the lesion to adjacent liver parenchyma using region of interests (ROI). Intra-class correlation (ICC) and kappa statistics with quadratic weights ( k) analysis, and maximally selected rank statistic were performed. Results: Substantial agreement between fellows ( k = 0.719; ICC = 0.705) and almost perfect agreement between attending radiologists ( k = 0.853; ICC = 0.849) were found for both qualitative and quantitative assessments of relative SI on delayed HPB imaging. A cut-off ratio to differentiate between hypointense and iso- to hyperintense lesions by ROI was calculated to be 0.90. Conclusion: Inter-observer agreement of liver lesion relative SI on delayed HBP imaging is high and may improve with radiologist experience. A cut-off ratio of relative SI at 0.90 may be useful to quantitatively distinguish hypointense from iso- to hyperintense liver lesions. [ABSTRACT FROM AUTHOR]

Background Leprosy is a chronic infectious disease produced by Mycobacterium leprae. In 1997 Venezuela reached the goal of elimination of leprosy as a public health problem (according to the World Health Organization a prevalence rate of ≤1/10,000 inhabitants), but five states still had prevalence rates over that goal. For this study we selected Cojedes State, where prevalence rates remain over the elimination goal. Objective Evaluate the real leprosy situation in high-prevalence areas of Cojedes State. Materials and methods Seven communities of Cojedes State were selected because they had the highest historic prevalence, as well as the highest prevalence in the year to be studied (1997). Results A rank correlation using Spearman's test comparing historical prevalence rates (1946-1996) and detection rates (1998-2004) gave a statistically significant P < 0.05 value. Diagnosed leprosy cases were as follows: age: 3.2% under 15 years old; sex: male/female rates between 60% and 91.66% males. The highest number of cases were paucibacillary forms: indeterminate leprosy (33.07%) and borderline tuberculoid leprosy (32.28%); tuberculoid leprosy (7.00%); and multibacillary cases (lepromatous leprosy, LL) were only 2.36%. Bacteriologically, 18.52 patients were M. leprae positive. At the moment of diagnosis, 96.6% showed no disabilities, 3.4% showed grade I disabilities, and there were no grade II or III disabilities. Conclusion This study confirms that several communities in Cojedes State have extremely high leprosy rates. [ABSTRACT FROM AUTHOR]

Orthohantavirus is a genus of globally distributed RNA viruses in the family Hantaviridae. In the Americas, the viruses are hosted by native rodent species within the Cricetidae family (2). Although [...]