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Background: To implement effective control measures, timely outbreak detection is essential. Shigella is the most common cause of bacterial diarrhea in Argentina. Highly resistant clones of Shigella have emerged, and outbreaks have been recognized in closed settings and in whole communities. We hereby report our experience with an evolving, integrated, laboratory-based, near real-time surveillance system operating in six contiguous provinces of Argentina during April 2009 to March 2012. Methodology: To detect localized shigellosis outbreaks timely, we used the prospective space-time permutation scan statistic algorithm of SaTScan, embedded in WHONET software. Twenty three laboratories sent updated Shigella data on a weekly basis to the National Reference Laboratory. Cluster detection analysis was performed at several taxonomic levels: for all Shigella spp., for serotypes within species and for antimicrobial resistance phenotypes within species. Shigella isolates associated with statistically significant signals (clusters in time/space with recurrence interval ≥365 days) were subtyped by pulsed field gel electrophoresis (PFGE) using PulseNet protocols. Principal Findings: In three years of active surveillance, our system detected 32 statistically significant events, 26 of them identified before hospital staff was aware of any unexpected increase in the number of Shigella isolates. Twenty-six signals were investigated by PFGE, which confirmed a close relationship among the isolates for 22 events (84.6%). Seven events were investigated epidemiologically, which revealed links among the patients. Seventeen events were found at the resistance profile level. The system detected events of public health importance: infrequent resistance profiles, long-lasting and/or re-emergent clusters and events important for their duration or size, which were reported to local public health authorities. Conclusions/Significance: The WHONET-SaTScan system may serve as a model for surveillance and can be applied to other pathogens, implemented by other networks, and scaled up to national and international levels for early detection and control of outbreaks. Author Summary: Shigellosis causes dysentery and kills an estimated 1.1 million people per year worldwide, 60% of them children under the age of 5. The infectious agent is Shigella spp, transmitted from person to person by fecal-oral route or via ingestion of contaminated food or water. Having a system for early detection of outbreaks would be very useful for implementing control measures that help reduce the number of affected patients, economic losses and prevent the dissemination of antimicrobial resistance. We present the application of a space-time permutation scan statistic implemented within the free SaTScan software for laboratory based surveillance of Shigella cases in six provinces from Argentina. SaTScan was applied on the data loaded into WHONET databases (an electronic laboratory data system used world-wide) in the six provinces from April 2009 to March 2012. The project allowed the identification of 32 events, including several of particular public health importance for their duration or number of affected patients. It also strengthened the relationship between the laboratory and epidemiology staff. In conclusion, the combination of WHONET laboratory data and SaTScan analysis can detect important community outbreaks of antimicrobial-resistant shigellosis in a timely manner, to make a difference to public health. [ABSTRACT FROM AUTHOR]

Background: To implement effective control measures, timely outbreak detection is essential. Shigella is the most common cause of bacterial diarrhea in Argentina. Highly resistant clones of Shigella have emerged, and outbreaks have been recognized in closed settings and in whole communities. We hereby report our experience with an evolving, integrated, laboratory-based, near real-time surveillance system operating in six contiguous provinces of Argentina during April 2009 to March 2012. Methodology: To detect localized shigellosis outbreaks timely, we used the prospective space-time permutation scan statistic algorithm of SaTScan, embedded in WHONET software. Twenty three laboratories sent updated Shigella data on a weekly basis to the National Reference Laboratory. Cluster detection analysis was performed at several taxonomic levels: for all Shigella spp., for serotypes within species and for antimicrobial resistance phenotypes within species. Shigella isolates associated with statistically significant signals (clusters in time/space with recurrence interval ≥365 days) were subtyped by pulsed field gel electrophoresis (PFGE) using PulseNet protocols. Principal Findings: In three years of active surveillance, our system detected 32 statistically significant events, 26 of them identified before hospital staff was aware of any unexpected increase in the number of Shigella isolates. Twenty-six signals were investigated by PFGE, which confirmed a close relationship among the isolates for 22 events (84.6%). Seven events were investigated epidemiologically, which revealed links among the patients. Seventeen events were found at the resistance profile level. The system detected events of public health importance: infrequent resistance profiles, long-lasting and/or re-emergent clusters and events important for their duration or size, which were reported to local public health authorities. Conclusions/Significance: The WHONET-SaTScan system may serve as a model for surveillance and can be applied to other pathogens, implemented by other networks, and scaled up to national and international levels for early detection and control of outbreaks. [ABSTRACT FROM AUTHOR]

The mid-shelf front ( MSF) of the Buenos Aires province continental shelf in the Southwestern Atlantic Ocean plays a central role in the pelagic ecosystem of the region acting as the main spring reproductive area for the northern population of the Argentine anchovy Engraulis anchoita and supporting high concentrations of chlorophyll as well as zooplankton, the main food of anchovy. To investigate the influence of environmental variability on the reproductive success of E. anchoita, we analyzed a 13-yr time series (1997-2009) of environmental data at MSF including chlorophyll dynamics, as well as zooplankton composition and abundance, ichthyoplankton distributions, and recruitment of E. anchoita. Spring chlorophyll concentrations showed high interannual variability and were mainly influenced by changes in water temperature and vertical stratification, which in turn control nutrient supply to the surface. Chlorophyll dynamics (magnitude, timing, and duration of the spring bloom) explained most of the variability observed in E. anchoita recruitment, most likely via fluctuations in the availability of adequate food for the larvae. Our results suggest that satellite ocean color products can be valuable tools for understanding variability in ecosystem dynamics and its effects on the recruitment of fish. [ABSTRACT FROM AUTHOR]

Themisto gaudichaudii and Euphausia lucens are important prey of several fish and squid species of commercial value in the southwest Atlantic Ocean. Although allometric relationships linking size and weight can be used to estimate prey biomass, size is often difficult to obtain as they are usually partly digested. The objective of our work was to provide length–length relationships to estimate body size of both crustaceans from their remains in fish stomachs, as a first step to estimate their weight. Measurements were performed on intact specimens collected in the field. Each of the body dimensions analysed (eye height and width for T. gaudichaudii, and carapace length and eye diameter for E. lucens) was significantly related to total length in both species. Thus, they appear to be highly reliable predictors of original size and can potentially aid in the identification of crustacean remains, allowing a more accurate analysis of digested contents. [ABSTRACT FROM AUTHOR]

Limitations to large-scale propagation of purple pitahaya ( Hylocereus costaricensis [F.A.C. Weber] Britton & Rose), a potential source of betalains for the food industry, can be overcome through utilization of in vitro culture technologies. In this work, successful in vitro propagation from areoles of adult purple pitahaya plants is reported. Factors affecting culture initiation, bud sprouting and growth, shoot multiplication, rooting, and acclimatization were studied. Best results for culture initiation were obtained from the central region of new joints by disinfection of large (5-7 cm in length) explants that were subsequently divided. Explants were sequentially treated with Extran® alkaline detergent for 10 min, followed by immersion in 70 % ( v/ v) ethanol for 15-30 s, a mixture of the fungicide Benomyl and the bactericide Agrymicin (2 g l each) for 30 min, and disinfection in sodium hypochlorite (1.0 % w/ v) for 15 min. Culture of sectioned individual areoles, without removing thorns, on Murashige and Skoog medium supplemented with 15 or 30 μM N-benzylaminopurine (BAP) for 3 mo with monthly subcultures, followed by transfer to the same medium with reduced BAP (0-2 μM), induced bud sprouting in over 80 % of explants, adequate growth of the shoots, with production of lateral shoots, and spontaneous rooting within 160 d. These plants were successfully acclimatized in vermiculite and peat moss (1:1), or perlite and peat moss (2:1) in the greenhouse, with over 90 % survival rate. One hundred percent of the in vitro-derived plants were successfully transferred to the field. Furthermore, these plants showed higher survival rates, larger height and increase in stem diameter than equivalent plants from the same genotype, derived from stem segments (the common clonal propagation system utilized for this species) that were simultaneously planted. [ABSTRACT FROM AUTHOR]

Copyright of Revista Colombiana de Biotecnología is the property of Universidad Nacional de Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The feeding of Engraulis anchoita was studied in the coastal reproductive habitat of the northern population during the spawning period. Stomach contents of anchovy adults and plankton samples taken during a research cruise were examined. The highest stomach fullness values were found in the Rio de la Plata estuary, particularly at stations close to the surface salinity front. Copepods, particularly those < 1 mm total length, represented by Paracalanus spp. and Oithona spp., were the most abundant prey. The dominance of small copepods in the Argentine anchovy diet is noted for the first time. Ecological implications of this fact are discussed. Other abundant preys were appendicularians, cladocerans, and fish eggs. The species composition of the zooplankton samples coincided roughly with that found in the stomach contents. However, selective feeding was observed on preys > 1 mm total length. This might be explained by a low gill rakers efficiency of adult anchovies to retain small prey. In the Rio de la Plata front, both the reported large biomasses of zooplankton and the observed intense anchovy feeding revealed the ecological significance of this front, especially when compared with the contiguous "poor in food" coastal areas. [ABSTRACT FROM AUTHOR]

The article presents a study on a specimen of Parvocalanus scotti found in Mar del Plata, Argentina. It says that P. scotti was synonymous to Paracalanus pygmaeus, which is among the prevailing copepod species of the Benguela Current community. The study used a single female specimen gathered at the coastal water in Estaci&#00F3;n Permanente de Estudios Ambientales (EPEA). Results show that P. scotti has a total length of 506 micrometer, vaulted cephalotorax, and stout head.

Copyright of Cirugía y Cirujanos is the property of Publicidad Permanyer SLU and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article presents a study that estimated the individual biomass of dominant copepod species, including Paracalanus parvus, Ctenocalanus vanus and Calanoides carinatus, in the coastal waters of the Argentine Sea and aimed to create regression models that can predict copepods' biovolume from some linear body dimensions. Researchers used volumetric methods and the geometric approach, the only suitable in the case of small-sized zooplankton, to achieve the desired results of the study. The article shows tables that depict the findings of the study including the mean body dimensions and estimated biovolume of adults and copepodite stages of copepods and the size-biovolume regressions of selected copepod species.

The article presents a study of the temporal fluctuations in appendicularian species composition, abundance, size structure, and biomass, and their relationships with physical and biological factors biweekly to monthly at a coastal station off Argentina, SW Atlantic Ocean. It is stated that the highest abundances and biomasses were recorded during spring-summer with a maximum in early January. It is said that abundance of Fritillaria borealis Lohmann, 1896 was related to temperature changes, being more abundant during fall-winter. It is said that Appendicularia sicula Fol, 1874 and Oikopleura fusiformis Fol, 1872 was present all year and was the dominant species.

The geographical and seasonal distribution of Cladocera was studied in the Argentine Sea, from the Río de la Plata River (34°S) to the Patagonian area (47°S). The cladoceran community included six species, which were found in the plankton especially in spring and summer and were absent during winter. Evadne nordmanni and Podon intermedius were the most widely distributed species, from 34°S to 44°S, in coastal and mid-shelf waters (MSW). Their Temperature-Salinity ranges of occurrence were around 8–21.7°C and 18–36.4‰. High numbers of E. nordmanni and P. intermedius were observed in the weakly stratified waters of the northpatagonian tidal front (42°S–45°S) compared to the other sectors of the frontal system. Pleopis polyphemoides mainly appeared north of 39°S in waters influenced by the Río de la Plata estuary (18–36.5‰) and it showed preference for warm waters. Podon leuckarti was present only in a few samples from cold coastal and MSW between 38°S and 44°S and seemed to be a stenohaline species (33.4–34.2‰). Penilia avirostris and Pseudoevadne tergestina were found north of 39°S particularly in coastal and MSW, but also in tropical and subtropical waters. Their Temperature-Salinity ranges of occurrence were 14–20.5°C and 27–36.5‰. Although the highest densities of Cladocera were found in neritic waters, our data suggests that some species may also inhabit oceanic waters. During early spring, E. nordmanni, P. polyphemoides, P. intermedius, and P. leuckarti were the first species to appear in the plankton in coastal waters off the Buenos Aires province, followed by P. avirostris and P. tergestina which gradually replaced the previously mentioned species and were dominant during the following summer. All species were absent during autumn and winter. [ABSTRACT FROM AUTHOR]

Copyright of Biomédica: Revista del Instituto Nacional de Salud is the property of Instituto Nacional de Salud of Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Deciphering the human spatial cognition system involves the development of simple tasks to assess how our brain works with shapes and forms. Prior studies in the mental rotation field disclosed a clockwise rotation bias on how basic stimuli are perceived and processed. However, there is a lack of a substantial scientific background for complex stimuli and how factors like sex or aging could influence them. Regarding the latter point, it is well known that our spatial skills tend to decline as we grow older. Hence, the hippocampal system is especially sensitive to aging. These neural changes underlie difficulties for the elderly in landmark orientation or mental rotation tasks. Thus, our study aimed to check whether the effect of clockwise and anticlockwise rotations in the spatial recognition of complex environments could be modulated by aging. To do so, 40 young adults and 40 old adults performed the ASMRT, a virtual spatial memory recognition test. Results showed that young adults outperformed old adults in all difficulty conditions (i.e., encoding one or three boxes positions). In addition, old adults were affected more than young adults by rotation direction, showing better performance in clockwise rotations. In conclusion, our study provides evidence that aging is particularly affected by the direction of rotation. We suggest that clockwise bias could be linked with the cognitive decline associated with aging. Future studies could address this with brain imaging measures. [ABSTRACT FROM AUTHOR]

SARS-CoV-2 infection produces a response of the innate immune system causing oxidative stress and a strong inflammatory reaction termed 'cytokine storm' that is one of the leading causes of death. Paraoxonase-1 (PON1) protects against oxidative stress by hydrolyzing lipoperoxides. Alterations in PON1 activity have been associated with pro-inflammatory mediators such as the chemokine (C-C motif) ligand 2 (CCL2), and the glycoprotein galectin-3. We aimed to investigate the alterations in the circulating levels of PON1, CCL2, and galectin-3 in 126 patients with COVID-19 and their interactions with clinical variables and analytical parameters. A machine learning approach was used to identify predictive markers of the disease. For comparisons, we recruited 45 COVID-19 negative patients and 50 healthy individuals. Our approach identified a synergy between oxidative stress, inflammation, and fibrogenesis in positive patients that is not observed in negative patients. PON1 activity was the parameter with the greatest power to discriminate between patients who were either positive or negative for COVID-19, while their levels of CCL2 and galectin-3 were similar. We suggest that the measurement of serum PON1 activity may be a useful marker for the diagnosis of COVID-19. [ABSTRACT FROM AUTHOR]

Background: A large number of articles in recent years studying the effects of non-surgically assisted tooth- versus bone-borne maxillary expanders in growing patients have found no significant differences in mid-palatal suture disjunction or even dentoalveolar changes. This suggests the need for new criteria and better use of current technology to make more effective devices and enhance the benefits of conventional treatments. This article describes a titanium grade V computer-aided design/computer-aided manufacturing (CAD/CAM) maxillary expander supported by two miniscrews, along with a 3D printed surgical guide. Methods: The first step was to obtain a digitized model of the patient's upper maxilla. To simplify the process and ensure the placement of the device in a high-quality bone area, the patients' digital dental cast was superimposed with a cone beam computed tomography (CBCT) scan. Improved resistance to expansion forces was secured through the use of 2 mm-wide miniscrews, long enough for bicortical anchorage. Placement site and direction were assessed individually in order to achieve primary stability. We chose a site between the second premolars and first molars, while the inclination followed the natural contour of the palate vault. A 3D-printed, polyamide surgical guide was designed to ensure the correct placement of the device with a manual straight driver. Results: Favorable clinical results were presented with 3D images. We confirmed a mid-palatal suture parallel separation of 3.63 mm, along with a higher palatal volume, as well as increased intercanine and intermolar distance. Segmentation of the facial soft tissue showed an expansion of nasal airways and changes in nasal morphology. Conclusions: Digital models, CBCT and CAD/CAM technology, are essential to accomplish the goals proposed in this article. Further studies are necessary to establish safer miniscrew placement sites and insertion angles so as to achieve greater in-treatment stability. Both the clinician and the patient can benefit from the use of current technology, creating new devices and updating traditional orthodontic procedures. [ABSTRACT FROM AUTHOR]

In order to control and eradicate epidemic cholera, we need to understand how epidemics begin, how they spread, and how they decline and eventually end. This requires extensive sampling of epidemic disease over time, alongside the background of endemic disease that may exist concurrently with the epidemic. The unique circumstances surrounding the Argentinian cholera epidemic of 1992–1998 presented an opportunity to do this. Here, we use 490 Argentinian V. cholerae genome sequences to characterise the variation within, and between, epidemic and endemic V. cholerae. We show that, during the 1992–1998 cholera epidemic, the invariant epidemic clone co-existed alongside highly diverse members of the Vibrio cholerae species in Argentina, and we contrast the clonality of epidemic V. cholerae with the background diversity of local endemic bacteria. Our findings refine and add nuance to our genomic definitions of epidemic and endemic cholera, and are of direct relevance to controlling current and future cholera epidemics. Pandemic cholera was reintroduced to Argentina in 1992, leading to epidemic spread. Here, the authors use whole genome sequencing to show how, over 6 years, epidemic cholera was caused by invariant 7PET lineage Vibrio cholerae, against a background of sporadic disease caused by diverse local strains. [ABSTRACT FROM AUTHOR]

We compiled an extensive dataset of copepod presence/absence data to define ecoregions in the southwestern South Atlantic (33°S–55°S) and to examine their relationships to water mass characteristics. We also investigated the role of mesoscale fronts in determining the boundaries of the ecoregions. Finally, we compared copepod distributions with previously defined biogeographical provinces in the southwestern South Atlantic. The regional copepod community is organized into six assemblages that occupy distinct areas of the shelf, the shelfbreak, and the oceanic realm. These areas are characterized by different water masses. In general, the spatial configuration of the ecoregions matches that of the previously defined regional biogeographic provinces and marine fronts seem to act as boundaries between the ecoregions. • Ecoregions based on copepods assemblages relate to water mass characteristics. • Marine fronts constitute boundaries of the ecoregions. • Ecoregions match the biogeographic provinces of the southwestern South Atlantic. [ABSTRACT FROM AUTHOR]

OBJECTIVES: The Berlin definition of acute respiratory distress syndrome (ARDS) was constructed for patients receiving invasive mechanical ventilation (IMV) with consideration given to issues related to reliability, feasibility, and validity. Notwithstanding, patients with acute respiratory failure (ARF) may be treated with high-flow nasal oxygen (HFNO) and may not fall within the scope of the original definition. We aimed to evaluate the predictive validity of the Berlin definition in HFNO-treated patients with COVID-19-related respiratory failure who otherwise met ARDS criteria. DESIGN: Multicenter, prospective cohort study. SETTING: Five ICUs of five centers in Argentina from March 2020 to September 2021. PATIENTS: We consecutively included HFNO-treated patients older than 18 years with confirmed COVID-19-related ARF, a Pa o 2/F io 2 of less than 300 mm Hg, bilateral infiltrates on imaging, and worsening respiratory symptoms for less than 1 week. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We evaluated the predictive validity of mortality at day 28 using the area under the receiver operating characteristics curve (AUC), compared the predictive validity across subgroups, and characterized relevant clinical outcomes. We screened 1,231 patients and included 696 ARDS patients [30 (4%) mild, 380 (55%) moderate, and 286 (41%) severe]. For the study cohort, the AUC for mortality at day 28 was 0.606 (95% CI, 0.561–0.651) with the AUC for subgroups being similar to that of the overall cohort. Two hundred fifty-six patients (37%) received IMV. By day 28, 142 patients (21%) had died, of whom 81 (57%) had severe ARDS. Mortality occurred primarily in patients who were transitioned to IMV. CONCLUSIONS: The predictive validity of the Berlin ARDS definition was similar for HFNO-treated patients as compared with the original population of invasively ventilated patients. Our findings support the extension of the Berlin definition to HFNO-treated patients with ARDS. [ABSTRACT FROM AUTHOR]

The diet of Engraulis anchoita larvae (Hubbs & Marini, 1935) was analyzed using samples collected once a month at a permanent coastal station off Buenos Aires Province, Argentina (Station EPEA), from March 2000 to April 2001. A total of 869 individuals were examined. Eggs (54.05%), copepod nauplii (10.13%), and copepodites (11.82%) were the dominant prey items. The feeding index varied from 1.69 to 40.48%, without showing a clear seasonal pattern. Correlations between predator size and prey size were determined and the results showed significant relationships (P < 0.01) in all cases. In spring and summer, the larvae were small in size, corresponding to first-feeding larvae (< 6.9 mm length) and preyed mainly on small organisms from < 45 to 134 µm width. In autumn and winter, the size of the larvae increased (7.0-19.9 mm length), and they fed mainly on larger prey, from 135 to 279 µm width. [ABSTRACT FROM AUTHOR]

The diet of Noctiluca scintillans was determined using samples collected monthly at a permanent coastal station off Buenos Aires Province, Argentina (Station EPEA) from March 2000 through April 2001. A total of 1100 individuals were examined. Diatoms (27.7%), copepod eggs (24,1%), and tintinnids (17.9%) were the main prey items. The genus/species of the most abundant preys found in the N. scintillans food vacuoles were, in declining order, the tintinnids Tintinnopsis spp., Codonellopsis spp., and Tintinnidium spp.; copepod eggs of Calanoides carinatus, Ctenocalanus vanus, and Oithona nana; and the diatoms Coscinodiscus wailesii, Paralia spp., Guinardia flaccida, Thalassiosira spp., Pinnularia spp., Pleurosigma normanii, and Triceratium spp. The alimentary incidence varied between 27.5% and 77.0%, with an average of 50.2%. This index reached a high value in the month of September 2000. The correlation between the volumes of predators and preys was highly significant (r = 0.1921; P < 0.00000). The results indicated that N. scintillans is a predator opportunist. [ABSTRACT FROM AUTHOR]

Abstract: Benzo[b]thiophenesulfonamide 1,1-dioxide derivatives (BTS) were described as candidate antineoplastic drugs. In the hope of finding new compounds with improved antitumour activity and reduced toxicity, we have designed and synthesized a small series of benzo[b]thiophene-6-carboxamide 1,1-dioxide derivatives (BTC) structurally related with the best reported BTS. Growth inhibition of HTB-54, CCRF-CEM and HeLa tumour cells lines at nanomolar concentrations was exhibited by some of the BTC. Hydrophobic substituents on the carboxamide group increased cytotoxicity but substitution by a hydroxy group diminished it, thus pointing to the electronic density on benzo[b]thiophene nucleus as a determinant factor. The process of cell death induced by BTC derivatives was further analyzed in CCRF-CEM cells, where these compounds induced apoptosis in a time and dose-dependent manner and cell cycle arrest at S phase. BTC derivatives also induced a significant increase in intracellular ROS levels in this cell line. Previous treatment of the cells with the antioxidant N-acetyl-cysteine abrogated the induction of apoptosis by BTC indicating that ROS generation is a previous event required to trigger the BTC induced apoptotic process. [ABSTRACT FROM AUTHOR]