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Achieving high velocities of magnetic domain walls is a crucial factor for their use as information carriers in modern nanoelectronic applications. In nanomagnetism and spintronics, these velocities are often limited either by internal domain wall instabilities, known as the Walker breakdown phenomenon, or by spin wave emission, known as the magnonic regime. In the rigid domain wall model, the maximum magnon velocity acts as an effective "speed of light", providing a relativistic analogy for the domain wall speed limitation. Cylindrical magnetic nanowires are an example of systems without the Walker breakdown phenomenon. Here we demonstrate that the magnonic limit could be outstandingly surpassed in cylindrical nanowires with high magnetization, such as iron. Our numerical modeling shows the Bloch point domain wall velocities as high as 14 km s-1, well above the magnonic limit estimated in the interval 1.7-2.0 km s-1. The key ingredient is the three-dimensional conical shape of the domain wall, which elongates and breaks during the dynamics, expelling backwards pairs of Bloch points. This leads to domain wall acceleration, the effect, which resembles the "jet propulsion". This effect will be very important for three-dimensional networks based on cylindrical magnetic nanowires.

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First-line tuberculostatic agents, Rifampicin (RIF), Isoniazid (ISH), Ethambutol (ETB), and Pyrazinamide (PZA) are generally administered as a fixed-dose combination (FDC) for improving patient adherence. The major quality challenge of these FDC products is their variable bioavailability, where RIF and its solid state are key factors. In this work, the analysis of the impact of the polymorphism in the performance of RIF in RIF-ISH and PZA-RIF-ISH combined products was carried out by an overall approach that included the development and validation of two methodologies combining near-infrared (NIR) spectroscopy and partial least squares (PLS) to the further evaluation of commercial products. For NIR-PLS methods, training and validation sets were prepared with mixtures of Form I/Form II of RIF, and the appropriate amount of ISH (for double associations) or ISH-PZA (for triple associations). The corresponding matrix of the excipients was added to the mixture of APIs to simulate the environment of each FDC product. Four PLS factors, reduced spectral range, and the combination of standard normal variate and Savitzky-Golay 1st derivative (SNV-D') were selected as optimum data pre-treatment for both methods, yielding satisfactory recoveries during the analysis of validation sets (98.5±2.0%, and 98.7±1.8% for double- and triple-FDC products, respectively). The NIR-PLS model for RIF-ISH successfully estimated the polymorphic purity of Form II in double-FDC capsules (1.02 ± 0.02w/w). On the other hand, the NIR-PLS model for RIF-ISH-PZA detected a low purity of Form II in triple FDC tablets (0.800 ± 0.021w/w), these results were confirmed by X-ray powder diffraction. Nevertheless, the triple-FDC tablets showed good performance in the dissolution test (Q=99-102%), implying a Form II purity about of 80% is not low enough to affect the safety and efficacy of the product.

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Bats are reservoirs of various coronaviruses that can jump between bat species or other mammalian hosts, including humans. This article explores coronavirus infection in three bat species (Tadarida brasiliensis, Eumops bonariensis, and Molossus molossus) of the family Molossidae from Argentina using whole viral metagenome analysis. Fecal samples of 47 bats from three semiurban or highly urbanized areas of the province of Santa Fe were investigated. After viral particle enrichment, total RNA was sequenced using the Illumina NextSeq 550 instrument; the reads were assembled into contigs and taxonomically and phylogenetically analyzed. Three novel complete Alphacoronavirus (AlphaCoV) genomes (Tb1-3) and two partial sequences were identified in T. brasiliensis (Tb4-5), and an additional four partial sequences were identified in M. molossus (Mm1-4). Phylogenomic analysis showed that the novel AlphaCoV clustered in two different lineages distinct from the 15 officially recognized AlphaCoV subgenera. Tb2 and Tb3 isolates appeared to be variants of the same virus, probably involved in a persistent infectious cycle within the T. brasiliensis colony. Using recombination analysis, we detected a statistically significant event in Spike gene, which was reinforced by phylogenetic tree incongruence analysis, involving novel Tb1 and AlphaCoVs identified in Eptesicus fuscus (family Vespertilionidae) from the U.S. The putative recombinant region is in the S1 subdomain of the Spike gene, encompassing the potential receptor-binding domain of AlphaCoVs. This study reports the first AlphaCoV genomes in molossids from the Americas and provides new insights into recombination as an important mode of evolution of coronaviruses involved in cross-species transmission. IMPORTANCE This study generated three novel complete AlphaCoV genomes (Tb1, Tb2, and Tb3 isolates) identified in individuals of Tadarida brasiliensis from Argentina, which showed two different evolutionary patterns and are the first to be reported in the family Molossidae in the Americas. The novel Tb1 isolate was found to be involved in a putative recombination event with alphacoronaviruses identified in bats of the genus Eptesicus from the U.S., whereas isolates Tb2 and Tb3 were found in different collection seasons and might be involved in persistent viral infections in the bat colony. These findings contribute to our knowledge of the global diversity of bat coronaviruses in poorly studied species and highlight the different evolutionary aspects of AlphaCoVs circulating in bat populations in Argentina.

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Comprehensive knowledge of the critical properties of the active pharmaceutical ingredients is a requirement within the modern concept of quality. Praziquantel hemihydrate (HH) and monohydrate (MH) are new solid forms of this antihelmintic agent, which have better solubility properties than the commercial anhydrous solid form (polymorph A). The thermal stability of the hydrates was evaluated, aiming to understand any possible transformation (amorphization, change to a less soluble form). Therefore, HH and MH were prepared along with the related anhydrous solid forms A and B, and characterized employing solid-state nuclear magnetic resonance, powder X-ray diffraction, mid and near infrared spectroscopy, thermal methods and the intrinsic dissolution rate. The transformations of HH and MH under thermal stress conditions were monitored through a variable temperature infrared spectroscopy approach, assisted by multivariate curve resolution with alternating least squares (MCR-ALS), finding that HH undergoes a two-step transformation (HH→B→A) to form A, whereas MH dehydrates directly into form A. This was further confirmed by conventional calorimetric methods (differential scanning calorimetry and thermogravimetry) and powder X-ray diffractometry. The impact of changes in the stressed solid forms and their dissolution rates was also assessed. Significant differences in dissolution performance were found regarding the solid forms produced as a consequence of thermally-induced dehydration.

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Bats are natural reservoirs of a variety of zoonotic viruses, many of which cause severe human diseases. Characterizing viruses of bats inhabiting different geographical regions is important for understanding their viral diversity and for detecting viral spillovers between animal species. Herein, the diversity of DNA viruses of five arthropodophagous bat species from Argentina was investigated using metagenomics. Fecal samples of 29 individuals from five species (Tadarida brasiliensis, Molossus molossus, Eumops bonariensis, Eumops patagonicus, and Eptesicus diminutus) living at two different geographical locations, were investigated. Enriched viral DNA was sequenced using Illumina MiSeq, and the reads were trimmed and filtered using several bioinformatic approaches. The resulting nucleotide sequences were subjected to viral taxonomic classification. In total, 4,520,370 read pairs were sequestered by sequencing, and 21.1% of them mapped to viral taxa. Circoviridae and Genomoviridae were the most prevalent among vertebrate viral families in all bat species included in this study. Samples from the T. brasiliensis colony exhibited lower viral diversity than samples from other species of New World bats. We characterized 35 complete genome sequences of novel viruses. These findings provide new insights into the global diversity of bat viruses in poorly studied species, contributing to prevention of emerging zoonotic diseases and to conservation policies for endangered species.

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The common vampire bat (Desmodus rotundus) is a sanguivorous (i.e., blood-eating) bat species distributed in the Americas from northern Mexico southwards to central Chile and Argentina. Desmodus rotundus is one of only three mammal species known to feed exclusively on blood, mainly from domestic mammals, although large wildlife and occasionally humans can also serve as a food source. Blood feeding makes D. rotundus an effective transmissor of pathogens to its prey. Consequently, this species is a common target of culling efforts by various individuals and organizations. Nevertheless, little is known about the historical distribution of D. rotundus. Detailed occurrence data are critical for the accurate assessment of past and current distributions of D. rotundus as part of ecological, biogeographical, and epidemiological research. This article presents a dataset of D. rotundus historical occurrence reports, including >39,000 locality reports across the Americas to facilitate the development of spatiotemporal studies of the species. Data are available at https://doi.org/10.6084/m9.figshare.15025296 .

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RESUMEN Introducción: El diagnóstico de hipertensión arterial (HTA) se realiza por la toma de la presión arterial (PA) en el consultorio médico (C) o en enfermería (E). Es frecuente aproximar los valores obtenidos a múltiplos de 10. Esto puede causar imprecisiones en el diagnóstico y el control de la HTA. Objetivo: Determinar cuántos registros de PA terminaban en cero en las mediciones realizadas en E y en C en dos centros de atención primaria de la salud de la ciudad de Salta. Material y métodos: Se efectuó un estudio descriptivo, transversal, de febrero a diciembre de 2018. Se utilizó un tensiómetro digital. A cada paciente se le midió la PA dos veces, primero en E y luego en C. Se utilizaron las pruebas de Chi2 y de Wilcoxon. Resultados: Se estudiaron 311 individuos, 60,77% mujeres. Edad media: 56,15 ± 13,8 años. Los registros terminados en cero tuvieron las siguientes frecuencias: PA sistólica en E: 36%; PA diastólica en E: 40,51%; PA sistólica en C: 11,58%; PA diastólica en C: 7,72% (p <0,0001). La PA sistólica y diastólica terminaron simultáneamente en cero en el 30,87% de los casos cuando se midieron en E y en el 0,64% de los casos cuando se midieron en C (p <0,0001). Conclusiones: La PA sistólica y la PA diastólica terminaron en cero con una frecuencia 3 y 5 veces mayor en E que en C, respectivamente, y la frecuencia de registros de PA sistólica y diastólica coincidentemente terminados en cero fue 48 veces mayor en E que en C. Estos resultados refuerzan la necesidad de una capacitación permanente para mejorar el registro en la medición de la PA.

ABSTRACT Background: The diagnosis of hypertension is established by blood pressure (BP) measurements in doctor (DO) or nursing offices (NO). Frecuently BP measurements are recorded as multiples of ten. This can lead to inaccuracy in diagnosis and control of hypertension. Objetive: To determine the percentage of BP measurements ending in zero in DO and NO, in the records of two health primary centers of Salta city. Methods: Observational study from february to december of 2018. Digital blood pressure monitor was used. Each patient BP was measured twice, first in NO and then in DO. Data were analyzed using the Chi2 and Wilcoxon tests. Results: 311 indivuals were enrolled, 60,77% were female. The average age was 56,15 ± 13,8 years. In NO the systolic BP and diastolic BP ending in zero were 36 and 40,51% respectively, while in DO were 11,58 and 7,72% (p <0,0001). The systolic BP and diastolic BP ending in zero simultaneously in NO was 30,87%, while in DO was 0,64% (p <0,0001). Conclusions: The systolic BP and the diastolic BP records ending in zero were three and five times more frequent in NO than in DO. The systolic BP and diastolic BP ending in zero simultaneously in NO were forty-eight times more frequent than in DO. These results reinforce the need of health personnel permanent training to improve precision for measuring and recording BP in medical centers.

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Meloxicam (MLX) is a non-steroidal anti-inflammatory drug, extensively used for inflammatory diseases and pain treatments, which exhibits five known solids forms. Form IV of MLX, a zwitterionic monohydrate (MH), is an emblematic hydrate case with promissory dissolution properties in a poorly soluble drug. However, the lack of information about MH stability regarding the dehydration process and phase transition impedes the development of further stability studies. A multi-spectroscopic/chemometric approach was implemented coupling middle- (MIR), near-infrared (NIR) and Raman spectroscopies to monitor the heat-mediated dehydration process of MH. The application of multivariate curve resolution-alternating least squares (MCR-ALS) to multi-source spectra by data fusion allow a complete view of the phenomena, improving the selectivity and precision to establish the transition temperatures and to identify involved species. It was revealed a two-step mechanism, where MH changes to Form V at 90 °C obtaining its complete dehydration at 130 °C, Form V remains unchanged during the temperature range 130-190 °C and then the polymorphic conversion to Form I starts, which reaches 100 % at 230 °C before melting MLX (248 °C). The findings of this work allow set targets in the process control of products using MH. Additionally, MCR-ALS detected an event not evidenced by conventional thermal analysis, the transformation of Form V to Form I.

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Pyrazinamide (PZA), Rifampicin (RIF), Isoniazid (ISH) and Ethambutol (ETB) form the core for the treatment of Tuberculosis, today a devastating disease in low-income populations around the world. These drugs are usually administrated by fixed-dose combination (FDC) products, to favour the patient compliance and prevent bacterial resistance. PZA exists in four enantiotropically-related polymorphs (Forms α, δ, ß and γ), but only Form α is considered suitable for pharmaceutical products due to its stability and bioavailability properties. The classical approaches to address solid-state (microscopy, X-ray diffraction and calorimetry) shows limitations for quantification of polymorphs in the presence of excipients and other active components, as in the case of FDC tablets. In this work, an overall strategy was developed using near infrared spectroscopy (NIR) coupled to partial least squares regression (PLS) to quantify Form α of PZA in drug substance (raw material) and PZA/RIF/ISH-FDC tablets. For this purpose, two PLS models were constructed, one for drug substance preparing training (n = 30) and validation (n = 18) samples with a ternary composition (Form α/Form δ/Form γ), and other for FDC drug products, also including the appropriate amount of RIF, ISH and the matrix of excipients in order to simulate the environment of PZA/RIF/ISH association. The NIR-PLS models were optimized using a novel smart approach based on radial optimization (full range, 3 L V and MSC-D' and SNV-D' as pre-treatment, for raw material and FDC tablets, respectively). During the validation step, both methods showed no bias or systematic errors and yielded satisfactory recoveries (102.5 ± 3.1 % for drug substance and 98.7 ± 1.5 % for FDC tablets). When commercial drug substance was tested, NIR-PLS was able to predict the content of Form α (0.98 ± 0.01 w/w). The model for FDC tablets allowed estimating polymorphic purity in intact (0.984 ± 0.003 w/w), sectioned (0.986 ± 0.002 w/w), and powered (0.985 ± 0.004 w/w) tablets, showing the methodology could be applied to a different stage of the process (i.e premixed-powders or granulates). The suitability of the method was also verified when Form α was satisfactorily analysed in FDC fortified with Form δ and Form γ to reach 0.78, 0.88 and 0.98 w/w, Form α. This strategy results in an excellent alternative to ensure the polymorphic purity of PZA throughout the overall pharmaceutical manufacturing process.

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Trypanosomes are a group of parasitic flagellates with medical and veterinary importance. Despite many species having been described in this genus, little is known about many of them. Here, we report a genetic and morphological characterization of trypanosomatids isolated from wild mammals from the Argentine Chaco region. Parasites were morphologically and ultrastructurally characterized by light microscopy and transmission electron microscopy. Additionally, 18s rRNA and gGAPDH genes were sequenced and analyzed using maximum likelihood and Bayesian inference. Morphological characterization showed clear characteristics associated with the Trypanosoma genus. The genetic characterization demonstrates that the studied isolates have identical sequences and a pairwise identity of 99% with Trypanosoma lainsoni, which belongs to the clade of lizards and snakes/rodents and marsupials. To date, this species had only been found in the Amazon region. Our finding represents the second report of T. lainsoni and the first record for the Chaco region. Furthermore, we ultrastructurally described for the first time the species. Finally, the host range of T. lainsoni was expanded (Leopardus geoffroyi, Carenivora, Felidae; and Calomys sp., Rodentia, Cricetidae), showing a wide host range for this species.

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Two new species of fleas of genus Ectinorus (Siphonaptera: Rhopalopsyllidae) are described from sigmodontine rodents (Rodentia: Cricetidae) collected during a survey of small mammals in northwestern Argentina.The new species belong to the subgenus Ectinorus and can be distinguished from all other species of the subgenus by the characteristics of the modified abdominal segments and by the genitalia. Moreover, the male of Ectinorus (Ectinorus) disjugis is described for the first time and the finding of this flea parasitizing the rodent Akodon spegazzinii, constitutes a new flea-host association. A phylogenetic analysis of the genus Ectinorus, using traditional morphological characters and morphogeometric data, is presented to support the erection of the new species of Ectinorus. An identification key for all species of Ectinorus is also provided. Our study increases to 38 the total number of species of the subgenus Ectinorus, and to 20 the number for Argentina. Phylogenetic analyses reveal that Ectinorus is monophyletic but the subgenera are not. This study offers a new interpretation of morphological diversity within the genus as well as an evaluation of hypotheses about their relationships.

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Anastrepha fraterculus (Wiedemann, 1830) is the main pest of fruit in southern Brazil. The use of toxic baits is one of the alternatives for its management. In this study, the toxic baits Anamed + malathion (10,000 mg/liter), Flyral 1.25% + malathion (2,000 mg/liter), and Gelsura (alpha-cypermethrin, 2,000 and 4,000 mg/liter) were highly toxic to the adults of A. fraterculus (lethal time [LT50] < 7 h). In contrast, Success 0.02 CB had an LT50 of 48.4 h. In the absence of rain, all the formulations had residual effects (>90% mortality) on A. fraterculus adults up to 21 d after treatment (DAT). In the presence of 5, 25, and 50 mm of rainfall, there was a significant reduction in the residual effect over time. However, with up to 50 mm of rain, Anamed + malathion and Gelsura 2,000 and 4,000 mg/liter caused between 43.0 and 79.0% of mortality. In the field, during two consecutive seasons (2015/2016 and 2016/2017), applications of Gelsura 2,000 mg/liter (four applications/season) caused population suppression of the pest throughout the apple fruiting period. However, in the 2016/2017 season, in the area using Gelsura, a higher percentage (≈12%) of apple fruits damaged by A. fraterculus females was observed when compared with the area with insecticide application (damage <3%). The toxic bait Gelsura (2,000 and 4.000 mg/liter) was shown to be promising for use in the management of A. fraterculus, with results similar to those with the application of synthetic insecticides.

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Bats provide important ecosystem services as pollinators, seed dispersers, and/or insect controllers, but they have also been found harboring different viruses with zoonotic potential. Virome studies in bats distributed in Asia, Africa, Europe, and North America have increased dramatically over the past decade, whereas information on viruses infecting South American species is scarce. We explored the virome of Tadarida brasiliensis, an insectivorous New World bat species inhabiting a maternity colony in Rosario (Argentina), by a metagenomic approach. The analysis of five pooled oral/anal swab samples indicated the presence of 43 different taxonomic viral families infecting a wide range of hosts. By conventional nucleic acid detection techniques and/or bioinformatics approaches, the genomes of two novel viruses were completely covered clustering into the Papillomaviridae (Tadarida brasiliensis papillomavirus type 1, TbraPV1) and Genomoviridae (Tadarida brasiliensis gemykibivirus 1, TbGkyV1) families. TbraPV1 is the first papillomavirus type identified in this host and the prototype of a novel genus. TbGkyV1 is the first genomovirus reported in New World bats and constitutes a new species within the genus Gemykibivirus. Our findings extend the knowledge about oral/anal viromes of a South American bat species and contribute to understand the evolution and genetic diversity of the novel characterized viruses.

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Praziquantel (PZQ) is a highly effective low-cost anthelmintic agent used as the first-choice treatment against schistosomiasis. The low solubility of the active is a major drawback for pharmaceutical formulation. A valid approach of the pharmaceutical industry for the improvement of the pharmacotechnical features of the active principles (such as solubility, processability, stability, among others), is the preparation of new solid forms, such as salts, polymorph, and pseudo-polymorph. Herein we report the preparation and characterization of a new solid form PZQ. The PZQ monohydrate (PZQ-MH) was prepared by a solventless procedure from the commercial racemate and the product was characterized at the solid-state employing optical digital microscopy, thermal methods (melting point, differential scanning calorimetry and thermogravimetric analysis), as well as and mid-infrared and near infrared spectroscopies. The chemical structure and content of water were full assessed by 1H nuclear magnetic resonance (NMR) in solution. The amount of water in PZQ-was also determined by different approaches, including thermogravimetric analysis and the loss on drying test. Solid-state 13C NMR (ssNMR) and X-ray powder diffraction (XRPD) completed the structural characterization of the new monohydrate. PZQ-MH showed a crystalline behavior during XRPD experiments and showed relevant differences in spectroscopic, calorimetric, ssNMR and XRPD signals when it was compared with the known crystal (Form A) and amorphous forms of PZQ. The determination of the intrinsic dissolution rate (IDR) of PZQ-MH was carried out as a functional characterization, observing that the new form had slightly higher IDR than Form A.

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Today, pharmaceutical products are submitted to a large number of analytical tests, planned to either ensure or construct their quality. The official methods of analysis used to perform these determinations are very different in nature, but almost all demand the intensive use of reagents and manpower as major drawbacks. Thus, analytical development is continuously evolving to find fast and smart approaches. First-order chemometric models are well-known in the pharmaceutical industry, and are extensively used in many fields. Such is the impact of chemometric models that regulatory agencies include them in guidelines and compendia. However, the mention or practical application of higher-order models in the pharmaceutical industry is rather scarce. Herein, we try to bring a brief introduction to chemometric models and useful literature references, focusing on higher-order chemometric models (HOCM) applied to reduce manpower, reagent consumption, and time of analysis, without sacrificing accuracy or precision, while gaining selectivity and sensitivity. The advantages and drawbacks of HOCM are also discussed, and the comparison to first-order chemometric models is also analyzed. Along the work, HOCM are evidenced as a powerful tool for the pharmaceutical industry; moreover, its implementation is shown during several steps of production, such as identification, purity test and assay, and other applications as homogeneity of API distribution, Process Analytical Technology (PAT), Quality by Design (QbD) or natural product fingerprinting. Among these topics, qualitative and quantitative applications were covered. Experimental approaches of chemometrics coupled to several analytical techniques such as UV-vis, fluorescence and vibrational spectroscopies (NIR, MIR and Raman), and other techniques as hyphenated-chromatography and electrochemical techniques applied to production and analysis are discussed throughout this work.

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Recurrent lymphocytic meningitis or Mollaret's meningitis is a rare condition caused by a number of infectious, autoimmune, toxic and neoplastic diseases. Herpes simplex type 2 is the most commonly isolated agent. It usually compromises middle aged women, with a self-limited clinical presentation that resolves within a week leaving no sequelae. Its diagnosis is mainly based on nucleic acid detection on cerebrospinal fluid. Antiviral prophylaxis has not shown conclusive to avoid recurrences.

La meningitis linfocítica recurrente o meningitis de Mollaret es una entidad asociada a un gran número de etiologías infecciosas, autoinmunes, toxicológicas y neoplásicas. En la actualidad el virus herpes simple tipo 2 (HSV-2) es el agente más frecuentemente aislado. Afecta frecuentemente a mujeres de mediana edad y tiende a autolimitarse sin secuelas dentro de la primera semana de inicio de síntomas. El diagnóstico se basa en la detección de ácidos nucleicos virales en el líquido cefalorraquídeo. Al momento no se ha demostrado beneficio en el uso de tratamiento antiviral en la prevención de recurrencias.

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La meningitis linfocítica recurrente o meningitis de Mollaret es una entidad asociada a un gran número de etiologías infecciosas, autoinmunes, toxicológicas y neoplásicas. En la actualidad el virus herpes simple tipo 2 (HSV-2) es el agente más frecuentemente aislado. Afecta frecuentemente a mujeres de mediana edad y tiende a autolimitarse sin secuelas dentro de la primera semana de inicio de síntomas. El diagnóstico se basa en la detección de ácidos nucleicos virales en el líquido cefalorraquídeo. Al momento no se ha demostrado beneficio en el uso de tratamiento antiviral en la prevención de recurrencias.

Recurrent lymphocytic meningitis or Mollaret´s meningitis is a rare condition caused by a number of infectious, autoimmune, toxic and neoplastic diseases. Herpes simplex type 2 is the most commonly isolated agent. It usually compromises middle aged women, with a self-limited clinical presentation that resolves within a week leaving no sequelae. Its diagnosis is mainly based on nucleic acid detection on cerebrospinal fluid. Antiviral prophylaxis has not shown conclusive to avoid recurrences.

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The development of a chemometric method for monitoring the pharmaceutical dissolution, under green analytical chemistry principles, was reported. Meloxicam (MEL) and pridinol (PRI) were employed as a combination model. Multivariate curve resolution with alternating least squares (MCR-ALS) was proposed to resolve UV spectra of the analytes during pharmaceutical dissolution. Empowering UV-vis spectrophotometry, which is considered an economical, ecological and fast technique, but poor in terms of selectivity. The developed method was validated in accordance to ICH guidelines, fulfilling acceptance criteria for linearity (r > 0.99 in the ranges 3.5-19.6 mg L-1 and 0.81-5.41 mg L-1 for MEL and PRI, respectively), accuracy (96.3% and 100.6% recoveries for MEL and PRI respectively), and precision (RSD < 10%) were evaluated using an independent validation set. Using a commercial sample, the method's accuracy was evaluated against HPLC analysis. Dissolution profiles were obtained using both methods. A point-to-point comparison with Moore and Flanner's factors (f1 and f2) were calculated. Specificity was evaluated by spectral correlation (R2>0.950). Additionally, the developed method works on-line and forgoes organic solvents and dilutions, lending itself to automation.

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A new species of flea (Siphonaptera: Rhopalopsyllidae) is described from sigmodontine rodents collected during a survey of small mammals in northwestern Argentina. The new species belongs to the subgenus Tetrapsyllus and can be distinguished from all species of the subgenus by characteristics of the modified abdominal segments and genitalia. A phylogenetic analysis of the genus Tetrapsyllus using morphological characters is presented and the analysis supports the erection of this new Tetrapsyllus species in the subgenus Tetrapsyllus. The unique occurrence of a sinus in the caudal margin of the sixth sternite of females that is present only in the subgenus Tetrapsyllus (also unique across the Order Siphonaptera) is provided with a discussion of how this adaptation is mirrored in the parallel development of a spur on the sclerotized inner tube of males. Additional host and locality data are recorded for Tetrapsyllus (P.) bleptus. A key to the genus Tetrapsyllus is provided. The increased diversity of flea fauna bordering a known plague endemic area in northwestern Argentina may prove useful in implementing sustainable control measures in the future.

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The assessment of polymorphism is a problematical issue for regulatory agencies, because variations among crystalline forms of active pharmaceutical ingredient (API) can lead to changes in the efficacy and safety of formulated product. Such conversions are very hard to be detected, thus, the development of techniques for the identification, characterization and quantification of polymorphs results essential in all stages of the manufacturing process. The presence of excipients in formulated products may change the crystal stability of an API, by catalyzing a polymorphic transformation or stabilizing the less stable form. As paradox, all suitable analytical techniques (spectroscopies, thermal analysis, NMR and DRX, and others) for polymorphic analysis are affected by excipients. A deep understanding of the polymorphism-excipient relationship is in full accordance with Quality by Design (QbD) paradigm, the systematic approach focused in quality building into a product based in the full understanding of the products and process. In this work, a novel approach based on thermal stress, MIR monitoring, multivariate curve resolution with alternating least squares (MCR-ALS) and kinetic analysis was developed and applied to monitor polymorphism behavior of model API in formulated products. Commercial tablets, physical mixtures and commercial API, were processed and analyzed under the proposed approach. Commercial tablets of MFA revealed a fast conversion to Form II, contrasting to the behavior of the pure API. Physical mixtures showed similar behavior to commercial tablets, thus reduction in transformation times was related to MFA-excipients physical interaction, even at surface level. Calorimetric studies support the conclusion obtained. The developed approach could be extended to others APIs and other stress sources (humidity, solvents, mechanical forces and its combinations), being a valuable tool for QbD environment.

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