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1.
N Engl J Med ; 387(7): 620-630, 2022 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-35830653

RESUMEN

BACKGROUND: Human adenoviruses typically cause self-limited respiratory, gastrointestinal, and conjunctival infections in healthy children. In late 2021 and early 2022, several previously healthy children were identified with acute hepatitis and human adenovirus viremia. METHODS: We used International Classification of Diseases, 10th Revision, codes to identify all children (<18 years of age) with hepatitis who were admitted to Children's of Alabama hospital between October 1, 2021, and February 28, 2022; those with acute hepatitis who also tested positive for human adenovirus by whole-blood quantitative polymerase chain reaction (PCR) were included in our case series. Demographic, clinical, laboratory, and treatment data were obtained from medical records. Residual blood specimens were sent for diagnostic confirmation and human adenovirus typing. RESULTS: A total of 15 children were identified with acute hepatitis - 6 (40%) who had hepatitis with an identified cause and 9 (60%) who had hepatitis without a known cause. Eight (89%) of the patients with hepatitis of unknown cause tested positive for human adenovirus. These 8 patients plus 1 additional patient referred to this facility for follow-up were included in this case series (median age, 2 years 11 months; age range, 1 year 1 month to 6 years 5 months). Liver biopsies indicated mild-to-moderate active hepatitis in 6 children, some with and some without cholestasis, but did not show evidence of human adenovirus on immunohistochemical examination or electron microscopy. PCR testing of liver tissue for human adenovirus was positive in 3 children (50%). Sequencing of specimens from 5 children showed three distinct human adenovirus type 41 hexon variants. Two children underwent liver transplantation; all the others recovered with supportive care. CONCLUSIONS: Human adenovirus viremia was present in the majority of children with acute hepatitis of unknown cause admitted to Children's of Alabama from October 1, 2021, to February 28, 2022, but whether human adenovirus was causative remains unclear. Sequencing results suggest that if human adenovirus was causative, this was not an outbreak driven by a single strain. (Funded in part by the Centers for Disease Control and Prevention.).


Asunto(s)
Infecciones por Adenovirus Humanos , Adenovirus Humanos , Hepatitis , Enfermedad Aguda , Infecciones por Adenovirus Humanos/complicaciones , Infecciones por Adenovirus Humanos/diagnóstico , Infecciones por Adenovirus Humanos/virología , Adenovirus Humanos/genética , Niño , Preescolar , Hepatitis/virología , Humanos , Lactante , Viremia
2.
Breast Cancer Res Treat ; 206(2): 317-328, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38561577

RESUMEN

PURPOSE: To evaluate the efficacy and safety of first-line therapy with palbociclib in a Spanish cohort treated after palbociclib approval. METHODS: PALBOSPAIN is an observational, retrospective, multicenter study evaluating real-world patterns and outcomes with 1 L palbociclib in men and women (any menopausal status) with advanced HR+/HER2- BC diagnosed between November 2017 and November 2019. The primary endpoint was real-world progression-free survival (rw-PFS). Secondary endpoints included overall survival (OS), the real-world response rate (rw-RR), the clinical benefit rate, palbociclib dose reduction, and safety. RESULTS: A total of 762 patients were included. The median rw-PFS and OS were 24 months (95% CI 21-27) and 42 months (40-not estimable [NE]) in the whole population, respectively. By cohort, the median rw-PFS and OS were as follows: 28 (95% CI 23-39) and 44 (95% CI 38-NE) months in patients with de novo metastatic disease, 13 (95% CI 11-17) and 36 months (95% CI 31-41) in patients who experienced relapse < 12 months after the end of ET, and 31 months (95% CI 26-37) and not reached (NR) in patients who experienced relapse > 12 months after the end of ET. rw-PFS and OS were longer in patients with oligometastasis and only one metastatic site and those with non-visceral disease. The most frequent hematologic toxicity was neutropenia (72%; grade ≥ 3: 52.5%), and the most common non-hematologic adverse event was asthenia (38%). CONCLUSION: These findings, consistent with those from clinical trials, support use of palbociclib plus ET as 1 L for advanced BC in the real-world setting, including pre-menopausal women and men. TRIAL REGISTRATION NUMBER: NCT04874025 (PALBOSPAIN). Date of registration: 04/30/2021 retrospectively registered.


Asunto(s)
Neoplasias de la Mama , Piperazinas , Piridinas , Receptor ErbB-2 , Humanos , Piridinas/uso terapéutico , Piridinas/efectos adversos , Piridinas/administración & dosificación , Femenino , Piperazinas/uso terapéutico , Piperazinas/administración & dosificación , Piperazinas/efectos adversos , Persona de Mediana Edad , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/metabolismo , Anciano , Adulto , Masculino , Estudios Retrospectivos , Receptor ErbB-2/metabolismo , Anciano de 80 o más Años , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Inhibidores de Proteínas Quinasas/uso terapéutico , Inhibidores de Proteínas Quinasas/efectos adversos , Inhibidores de Proteínas Quinasas/administración & dosificación , Supervivencia sin Progresión
3.
Glob Chang Biol ; 30(5): e17334, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38780465

RESUMEN

The crises of climate change and biodiversity loss are interlinked and must be addressed jointly. A proposed solution for reducing reliance on fossil fuels, and thus mitigating climate change, is the transition from conventional combustion-engine to electric vehicles. This transition currently requires additional mineral resources, such as nickel and cobalt used in car batteries, presently obtained from land-based mines. Most options to meet this demand are associated with some biodiversity loss. One proposal is to mine the deep seabed, a vast, relatively pristine and mostly unexplored region of our planet. Few comparisons of environmental impacts of solely expanding land-based mining versus extending mining to the deep seabed for the additional resources exist and for biodiversity only qualitative. Here, we present a framework that facilitates a holistic comparison of relative ecosystem impacts by mining, using empirical data from relevant environmental metrics. This framework (Environmental Impact Wheel) includes a suite of physicochemical and biological components, rather than a few selected metrics, surrogates, or proxies. It is modified from the "recovery wheel" presented in the International Standards for the Practice of Ecological Restoration to address impacts rather than recovery. The wheel includes six attributes (physical condition, community composition, structural diversity, ecosystem function, external exchanges and absence of threats). Each has 3-5 sub attributes, in turn measured with several indicators. The framework includes five steps: (1) identifying geographic scope; (2) identifying relevant spatiotemporal scales; (3) selecting relevant indicators for each sub-attribute; (4) aggregating changes in indicators to scores; and (5) generating Environmental Impact Wheels for targeted comparisons. To move forward comparisons of land-based with deep seabed mining, thresholds of the indicators that reflect the range in severity of environmental impacts are needed. Indicators should be based on clearly articulated environmental goals, with objectives and targets that are specific, measurable, achievable, relevant, and time bound.


Asunto(s)
Minería , Biodiversidad , Ecosistema , Ambiente , Conservación de los Recursos Naturales , Cambio Climático
4.
Arch Biochem Biophys ; 758: 110077, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38942109

RESUMEN

Ammonium and hexyltrimethylammonium thiomolybdates (ATM and ATM-C6) and thiotungstates (ATT and ATT-C6) were synthesized. Their toxicity was evaluated using both in vitro and in vivo approaches via the zebrafish embryo acute toxicity assay (ZFET), while the copper-thiometallate interaction was studied using cyclic voltammetry, as well as in an in vivo assay. Cyclic voltammetry suggests that all thiometallates form complexes with copper in a 2:1 Cu:thiometallate ratio. Both in vitro and in vivo assays demonstrated low toxicity in BALB/3T3 cells and in zebrafish embryos, with high IC50 and LC50 values. Furthermore, the hexyltrimethylammonium ion played a crucial role in enhancing viability and reducing toxicity during prolonged treatments for ATM and ATT. In particular, the ZEFT assay uncovered the accumulation of ATM in zebrafish yolk, averted by the incorporation of the hexyltrimethylammonium ion. Notably, the copper-thiometallate interaction assay highlighted the improved viability of embryos when cultured in CuCl2 and ATM-C6, even at high CuCl2 concentrations. The hatching assay further confirmed that copper-ATM-C6 interaction mitigates inhibitory effects induced by thiomolybdates and CuCl2 when administered individually. These results suggest that the incorporation of the hexyltrimethylammonium ion in ATM increase its ability to interact with copper and its potential application as a copper chelator.

5.
Phys Chem Chem Phys ; 26(8): 6752-6762, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38323460

RESUMEN

The O(3P) + D2 → OD(2Π) + D reaction presents the peculiarity of taking place on two different potential energy surfaces (PESs) of different symmetry, 3A' and 3A'', which become degenerate for collinear configurations where the saddle-point of the reaction is located. The degeneracy is broken for non-collinear approaches with the energy on the 3A' PES rising more abruptly with the bending angle, making the frequency of this mode higher on the 3A' state. Consequently, the 3A' PES should be less reactive than the 3A'' one. Nevertheless, quantum scattering calculations show that the cross section is higher on the 3A' PES for energies close to the classical reaction threshold and rotationless reactant. It is found that the differences between the reactivity on the two PESs are greater for low values of total angular momentum, where the centrifugal barrier is lower and contribute to the higher population of the Π(A') Λ-doublet states of OD at low collision energies. At high collision energies, the Π(A') Λ-doublet state is also preferentially populated. Analysis of the differential cross sections reveals that the preponderance for the Π(A') Λ-doublet at low energies comes from backward scattering, originating from the reaction on the 3A' PES, while at high energies, it proceeds from a different mechanism that leads to sideways scattering on the 3A'' PES and that populates the Π(A') manifold.

6.
Osteoporos Int ; 34(11): 1881-1891, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37418151

RESUMEN

Realising the benefits of systematic secondary fracture prevention requires supporting local sites to get started and becoming effective. We here describe the development, implementation and impact of a regional fracture liaison service (FLS) mentorship programme in Latin America that led to 64 FLS getting started and coverage of 17,205 patients. INTRODUCTION: Despite treatments and service models to deliver effective secondary fracture prevention, most patients are left untreated after a fragility fracture. To improve the capability to get FLS started and more effective, we describe the development, implementation and evaluation of an international programme to develop national communities of FLS mentors as part of the Capture the Fracture Partnership in Latin America. METHODS: The IOF regional team and the University of Oxford developed the curriculum and associated resources for training mentors in setting up FLS, service improvement and mentorship. Mentors were selected during a preparatory meeting, trained using live online sessions followed by regular mentor-led post-training meetings. The programme was evaluated using a pre-training needs assessment and post-training evaluation based on Moore's outcomes. RESULTS: The mentorship programme was initiated in Mexico, Brazil, Colombia and Argentina. The mentors were multidisciplinary, including orthopaedic surgery, rehabilitation, rheumatology, endocrinology, geriatrics, gynaecology and internal medicine. There was 100% participation in training sessions and reported satisfaction with the training. Since the initiation of the training programme, 22 FLS have been set up in Mexico, 30 in Brazil, 3 in Colombia and 9 in Argentina, in comparison with two in Chile and none in any other LATAM countries that were not involved in the mentorship programme. This equates to approximately 17,025 additional patients identified from 2019 to 2021 after initiation of mentorship. The mentors have engaged with 58 FLS for service development. Post-training activities include two published national best practice guidelines and other country-specific resources for FLS in the local language. CONCLUSION: Despite the COVID pandemic, the mentorship pillar of the Capture the Fracture Partnership has developed a community of FLS mentors with measurable improvement in national FLS provision. The programme is a potentially scalable platform to develop communities of mentors in other countries.


Asunto(s)
COVID-19 , Fracturas Osteoporóticas , Humanos , Fracturas Osteoporóticas/prevención & control , Mentores , América Latina , México , Prevención Secundaria
7.
Opt Lett ; 48(20): 5435-5438, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37831886

RESUMEN

We show that the Markovian dynamics of two coupled harmonic oscillators may be analyzed using a Schrödinger equation and an effective non-Hermitian Hamiltonian. This may be achieved by a non-unitary transformation that involves superoperators; such transformation enables the removal of quantum jump superoperators, which allows us to rewrite the Lindblad master equation in terms of a von Neumann-like equation with an effective non-Hermitian Hamiltonian. This may be generalized to an arbitrary number of interacting fields. Finally, by applying an extra non-unitary transformation, we may diagonalize the effective non-Hermitian Hamiltonian to obtain the evolution of any input state in a fully quantum domain.

8.
Psychol Med ; 53(6): 2553-2562, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-35094717

RESUMEN

BACKGROUND: Racial and ethnic groups in the USA differ in the prevalence of posttraumatic stress disorder (PTSD). Recent research however has not observed consistent racial/ethnic differences in posttraumatic stress in the early aftermath of trauma, suggesting that such differences in chronic PTSD rates may be related to differences in recovery over time. METHODS: As part of the multisite, longitudinal AURORA study, we investigated racial/ethnic differences in PTSD and related outcomes within 3 months after trauma. Participants (n = 930) were recruited from emergency departments across the USA and provided periodic (2 weeks, 8 weeks, and 3 months after trauma) self-report assessments of PTSD, depression, dissociation, anxiety, and resilience. Linear models were completed to investigate racial/ethnic differences in posttraumatic dysfunction with subsequent follow-up models assessing potential effects of prior life stressors. RESULTS: Racial/ethnic groups did not differ in symptoms over time; however, Black participants showed reduced posttraumatic depression and anxiety symptoms overall compared to Hispanic participants and White participants. Racial/ethnic differences were not attenuated after accounting for differences in sociodemographic factors. However, racial/ethnic differences in depression and anxiety were no longer significant after accounting for greater prior trauma exposure and childhood emotional abuse in White participants. CONCLUSIONS: The present findings suggest prior differences in previous trauma exposure partially mediate the observed racial/ethnic differences in posttraumatic depression and anxiety symptoms following a recent trauma. Our findings further demonstrate that racial/ethnic groups show similar rates of symptom recovery over time. Future work utilizing longer time-scale data is needed to elucidate potential racial/ethnic differences in long-term symptom trajectories.


Asunto(s)
Depresión , Trastornos por Estrés Postraumático , Humanos , Niño , Depresión/psicología , Trastornos de Ansiedad , Ansiedad/epidemiología , Trastornos por Estrés Postraumático/epidemiología , Trastornos por Estrés Postraumático/diagnóstico , Etnicidad/psicología
9.
Angew Chem Int Ed Engl ; 62(37): e202308749, 2023 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-37483088

RESUMEN

The synthesis of a series of triangular-shaped tricarboxamides endowed with three picoline or nicotine units (compounds 2 and 3, respectively) or just one nicotine unit (compound 4) is reported, and their self-assembling features investigated. The pyridine rings make compounds 2-4 electronically complementary with our previously reported oligo(phenylene ethynylene)tricarboxamides (OPE-TA) 1 to form supramolecular copolymers. C3 -symmetric tricarboxamide 2 forms highly stable intramolecular five-membered pseudocycles that impede its supramolecular polymerization into poly-2 and the co-assembly with 1 to yield copolymer poly-1-co-2. On the other hand, C3 -symmetric tricarboxamide 3 readily forms poly-3 with great stability but unable to form helical supramolecular polymers despite the presence of the peripheral chiral side chains. The copolymer poly-1-co-3 can only be obtained by a previous complete disassembly of the constitutive homopolymers in CHCl3 . Helical poly-1-co-3 arises in a process involving the transfer of the helicity from racemic poly-1 to poly-3, and the amplification of asymmetry from chiral poly-3 to poly-1. Importantly, C2v -symmetric 4, endowed with only one nicotinamide moiety and three chiral side chains, self-assembles into a P-type helical supramolecular polymer (poly-4) in a thermodynamically controlled cooperative process. The combination of poly-1 and poly-4 generates chiral supramolecular copolymer poly-1-co-4, whose blocky microstructure has been investigated by applying the previously reported supramolecular copolymerization model.

10.
J Struct Biol ; 214(3): 107884, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35908727

RESUMEN

Apoptosis is the best-known programmed cell death that maintains tissue homeostasis in eukaryotic cells. The morphological characteristics include nuclear and cytoplasmic contraction and cytoplasmic blebbing, its biochemical hallmarks include caspase protease activity and DNA fragmentation. In rat ovaries, cell death is a normal process that occurs throughout the organism's life. Granulosa cells, the more abundant cell type forming the ovarian follicles, are eliminated via different routes of cell death. Most granulosa cells are eliminated through apoptotic cell death. In this work, we analyzed the behavior of nuclear components throughout the apoptotic process and determined how they are regionalized and conserved during follicular atresia in rat ovaries. Apoptosis was detected based on caspase-3 activity and DNA fragmentation using the TUNEL technique. We identified the transcription markers H3ac and RNA Pol II, and splicing factor SC35 by immunodetection. The nucleolar components were analyzed via light microscopy and transmission electron microscopy through immunodetection of the proteins nucleolin and nucleophosmin-1. The nuclear ultrastructure was analyzed using standard contrast and preferential ribonucleoprotein contrast. Our results demonstrate that during the progression of apoptosis, chromatin is remodeled to constitute apoptotic bodies; transcription and spliceosome elements are reorganized along with the nucleolar components. Additionally, the splicing and transcription factors are segregated into specific territories inside the apoptotic bodies, suggesting that transcriptional elements are reorganized during the apoptotic process. Our results indicate that apoptotic bodies not only are compacted, and chromatin degraded but all the nuclear components are progressively reorganized during cell elimination; moreover, the transcriptional components are preserved.


Asunto(s)
Apoptosis , Atresia Folicular , Animales , Apoptosis/genética , Cromatina/genética , Femenino , Atresia Folicular/metabolismo , Etiquetado Corte-Fin in Situ , Factores de Empalme de ARN , Ratas
11.
Opt Express ; 30(9): 14384-14392, 2022 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-35473182

RESUMEN

A novel method that enables simultaneous and discriminative measurement of strain and temperature using one single optical fiber is presented. The method is based on the properties of transverse acoustic mode resonances (TAMRs) of the optical fiber. In particular, it is based on the different sensitivity to temperature and strain that exhibit the radial modes R0,m and a family of torsional-radial modes denoted as T R2,m(1). We show that the resonance frequencies of both types of resonances shift linearly with temperature and strain, but at different rates. By the combined use of the different sensitivities of the two families of TAMRs, we experimentally demonstrate discriminative measurements of strain and temperature. A detection limit of strain and temperature better than 25 µÎµ and 0.2 °C is achieved.

12.
Opt Express ; 30(1): 42-52, 2022 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-35201193

RESUMEN

Transverse acoustic mode resonances enable a high accuracy determination of Poisson's ratio and elastic properties of optical fibers. An all-optical pump and probe technique is used for efficient excitation and accurate characterization of both, radial and torsional-radial acoustic resonances of optical fibers. Simple and precise algebraic expressions for the frequencies of high order acoustic resonances are derived, enabling a rigorous analysis of the experimental data using standard least squares fitting. Following this approach, the determination of Poisson's ratio does not require the measurement of any physical length, but only frequency measurements are required. An accuracy better than 1 ‰ is achieved. The dependence of the fiber Poisson's ratio with temperature is also determined experimentally.

13.
Hum Reprod ; 37(8): 1774-1785, 2022 07 30.
Artículo en Inglés | MEDLINE | ID: mdl-35652237

RESUMEN

STUDY QUESTION: What number of staff is sufficient to perform increasingly complicated processes in today's modern ART laboratories? SUMMARY ANSWER: The adequate number of personnel required for the efficient and safe operation of modern ART laboratories needs to be calculated. WHAT IS KNOWN ALREADY: In today's modern ART laboratories, the amount of time required to perform increasingly complicated processes has more than doubled, with a downward trend in the amount of work an embryologist can do. Different workload unit values have been used to evaluate each workload task and efficiency in a particular ART laboratory, as well as to occasionally compare one laboratory with another. STUDY DESIGN, SIZE, DURATION: Seven senior embryologists working at different IVF centers, three public and four private centers, participated in this multicenter study conducted between 2019 and 2020. We prepared a survey to create a calculator for staff using the average (of three attempts) time spent in every laboratory by each embryologist of the center to perform any ART process. PARTICIPANTS/MATERIALS, SETTING, METHODS: Different laboratory processes and activities related to quality control, time spent and conventional human double witnessing were included in the survey. To calculate the number of processes that each embryologist can perform per year, an embryologist was considered to be having a full-time contract and working 7 or 8 h/day. The times included in the calculation of each task were those corresponding to the 95th percentile. For the calculations, Microsoft® Office Excel® Professional Plus 2019 was used. MAIN RESULTS AND THE ROLE OF CHANCE: The survey showed that the time needed per embryologist to perform the different processes necessary for a classic IVF cycle without time lapse (TL) was 8.11 h, and with TL, it was 10.27 h. The calculated time also considered the time spent in documentation handling, cycle preparation, database management and conventional human double witnessing verification. An ICSI without TL needed 8.55 h, and with TL, it needed 10.71 h. An ICSI-PGT without a TL cycle needed 11.75 h, and with TL, it needed 13.91 h. Furthermore, 1.81 h should be added for every vitrification support needed. The time needed to control more than 200 critical steps, including equipment control and culture parameters, was 30 min per day plus 3.9 min per device to control.The time spent in semen analysis (including documentation handling, cycle preparation and database management) or intrauterine insemination with a partner sperm was 2.7 h. For donor sperm, an additional hour was required for the management involved. The time required to perform a testicular biopsy and cryopreserve the sample was 4 h. Similarly, the time required to perform seminal cryopreservation was 3.7 h. LIMITATIONS, REASONS FOR CAUTION: The study was conducted considering a full-time contract embryologist working 7 or 8 h/day, 5 days a week, with days off according to the Spanish regulations. However, our findings can be adapted to foreign regulations using the developed online calculation platform. WIDER IMPLICATIONS OF THE FINDINGS: A new advanced staff calculator allows any IVF laboratory to estimate the minimum number of embryologists necessary without compromising the security or success of the results. Nevertheless, we recommend a minimum of two qualified embryologists in every laboratory, regardless of the workload. STUDY FUNDING/COMPETING INTEREST(S): This work was funded by the Asociación para el Estudio de la Biología de la Reproducción (ASEBIR). None of the authors has any conflict of interest to declare. TRIAL REGISTRATION NUMBER: N/A.


Asunto(s)
Laboratorios , Semen , Fertilización In Vitro/métodos , Humanos , Masculino , Técnicas Reproductivas Asistidas , Vitrificación
14.
Phys Rev Lett ; 128(24): 241801, 2022 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-35776450

RESUMEN

We present a measurement of ν_{e} interactions from the Fermilab Booster Neutrino Beam using the MicroBooNE liquid argon time projection chamber to address the nature of the excess of low energy interactions observed by the MiniBooNE Collaboration. Three independent ν_{e} searches are performed across multiple single electron final states, including an exclusive search for two-body scattering events with a single proton, a semi-inclusive search for pionless events, and a fully inclusive search for events containing all hadronic final states. With differing signal topologies, statistics, backgrounds, reconstruction algorithms, and analysis approaches, the results are found to be either consistent with or modestly lower than the nominal ν_{e} rate expectations from the Booster Neutrino Beam and no excess of ν_{e} events is observed.

15.
J Phys Chem A ; 126(14): 2244-2261, 2022 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-35363491

RESUMEN

We report for the first time an accurate ab initio potential energy surface for the HeH+-H2 system in four dimensions (4D) treating both diatomic species as rigid rotors. The computed ab initio potential energy point values are fitted using an artificial neural network method and used in quantum close coupling calculations for different initial states of both rotors, in their ground electronic states, over a range of collision energies. The state-to-state cross section results are used to compute the rate coefficients over a range of temperatures relevant to interstellar conditions. By comparing the four dimensional quantum results with those obtained by a reduced-dimensions approach that treats the H2 molecule as an averaged, nonrotating target, it is shown that the reduced dimensionality results are in good accord with the four dimensional results as long as the HeH+ molecule is not initially rotationally excited. By further comparing the present rate coefficients with those for HeH+-H and for HeH+-He, we demonstrate that H2 molecules are the most effective collision partners in inducing rotational excitation in HeH+ cation at interstellar temperatures. The rotationally inelastic rates involving o-H2 and p-H2 excitations are also obtained and they turn out to be, as in previous systems, orders of magnitude smaller than those involving the cation. The results for the H2 molecular partner clearly indicate its large energy-transfer efficiency to the HeH+ system, thereby confirming its expected importance within the kinetics networks involving HeH+ in interstellar environments.

16.
Artículo en Inglés | MEDLINE | ID: mdl-35899400

RESUMEN

Summary: Background. The sensitization profile of patients allergic to house dust mites (HDM) and its molecular diagnosis may determine treatment and evolution of the disease. The present study investigates the prevalence of Der p 23 sensitization and its relation to asthma in a population of HDM-allergic patients. Methods. We conducted a cross-sectional study of 891 patients with HDM allergy with symptoms of rhinitis and 52.1% of them with asthma. Total and specific IgE (sIgE) was measured against Dermatophagoides pteronyssinus and its molecular components (Der p 1, Der p 2 and Der p 23) and the storage mite Lepidoglyphus destructor using ImmunoCAP. Prevalence of sensitization and levels of sIgE were analysed according to asthma diagnosis and asthma severity. Results. Der p 23 was the predominant allergen in this population (83.7%) but IgE levels were lower than those of sIgE to Der p 1 and Der p 2. A good correlation was found between sIgE to Der p 23 and the other allergens. A total of 8.2% patients were monosensitized to Der p 23. Asthma was more frequent in patients with positive sIgE against Der p 23 than in patients without this sensitization (52.8% vs 42.8%, p = 0.027). A tendency to increase both total IgE and sIgE was observed in relation to the severity of asthma from intermittent mild asthma to persistent moderate asthma but a substantial decrease in total IgE and sIgE was detected in more severe asthmatics. Conclusions. Der p 23 might be a prevalent allergen in regions with high rates of HDM exposure. Even though sIgE levels against this allergen are usually low, its presence could increase the risk of asthma.

17.
J Helminthol ; 96: e30, 2022 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-35465856

RESUMEN

An annotated checklist of the helminth parasites associated with reptiles from Peru is provided, as the result of a compilation of parasitological papers published between 1963 and January 2022 and records of species deposited in national and international collections. The list provides data on hosts, developmental stage, sites of infection, geographical distribution in Peruvian territory, code of material deposited in helminthological collections, references and taxonomic notes. The database includes records of 106 different species of helminth parasites (82 nominal species and 24 taxa identified at the generic level), the majority in the adult stage. These helminth parasites come from 18 of the 25 official Peruvian regions. Nematodes have the highest richness in number of species (79 species), followed by trematodes (17 species) and cestodes (nine species). The acanthocephalans are represented by only one species. The parasites with the highest number of records were Physaloptera retusa Rudolphi, 1819 (11 hosts), Physalopteroides venancioi (Lent, Freitas & Proença, 1946) (nine hosts), Strongyluris oscari Travassos, 1923 (seven hosts), and Parapharyngodon scleratus Travassos, 1923 (five hosts), all of which are nematodes. The 106 taxa of helminth parasites have been reported infecting 55 species of reptiles in Peru, distributed in 34 genera and 14 families. The reptile species harbouring the highest number of helminth parasites are the yellow-footed tortoise Chelonoidis denticulatus (Linnaeus) with 18 species (three trematodes and 15 nematodes), followed by the Peru desert tegu Dicrodon guttulatum Duméril & Bibron (Teiidae) with 11 species (three cestodes and eight nematodes) and the yellow-spotted Amazon River turtle Podocnemis unifilis Troschel (Podocnemididae) with 10 species (five trematodes and five nematodes). Of the 524 species of reptiles reported in Peru, only 55 (>10%) are reported as hosts of helminths representing a small proportion considering the great variety of reptile hosts that inhabit the various tropical and subtropical geographical areas of Peru.


Asunto(s)
Cestodos , Infecciones por Cestodos , Helmintos , Parásitos , Tortugas , Animales , Lista de Verificación , Humanos , Perú , Reptiles/parasitología , Vertebrados
18.
Phys Rev Lett ; 126(8): 083401, 2021 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-33709729

RESUMEN

We investigate the photoassociation dynamics of exactly two laser-cooled ^{85}Rb atoms in an optical tweezer and reveal fundamentally different behavior to photoassociation in many-atom ensembles. We observe nonexponential decay in our two-atom experiment that cannot be described by a single rate coefficient and find its origin in our system's pair correlation. This is in stark contrast to many-atom photoassociation dynamics, which are governed by decay with a single rate coefficient. We also investigate photoassociation in a three-atom system, thereby probing the transition from two-atom dynamics to many-atom dynamics. Our experiments reveal additional reaction dynamics that are only accessible through the control of single atoms and suggest photoassociation could measure pair correlations in few-atom systems. It further showcases our complete control over the quantum state of individual atoms and molecules, which provides information unobtainable from many-atom experiments.

19.
J Phys Chem A ; 125(17): 3748-3759, 2021 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-33899485

RESUMEN

Ab initio calculations are employed to generate the rigid rotor (RR) potential energy surface (PES) describing the interaction of the linear molecular cation HeHHe+, at its equilibrium geometry, with the neutral He atom. The resulting interaction is employed to investigate the efficiency of rotational state-changing collisions at the temperatures relevant to the early universe conditions, where the latter molecule has been postulated to exist, albeit not yet observed. The inelastic rate coefficients are found to be fairly large and are compared with those found for another important cation just recently observed in the interstellar medium: the HeH+ polar molecule. The possibility for this cation to provide new options to energy dissipation routes under early universe conditions after the recombination era is briefly discussed.

20.
J Chem Phys ; 155(15): 154301, 2021 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-34686057

RESUMEN

By extending an earlier study [Gianturco et al., J. Chem. Phys. 154, 054311 (2021)] on the purely rotational excitation of HeH+ by He atoms, we report in this paper integral cross sections and rate coefficients for rovibrational excitation and de-excitation processes in HeH+ due to collisions with He. The data were obtained using a new ab initio potential energy surface that includes the vibrational degree of freedom. The results are compared with those computed using the earlier potential energy surface by Panda and Sathyamurthy [J. Phys. Chem. A 107, 7125 (2003)] that additionally accounts for the proton-exchange reaction between HeH+ and He. It is shown that the exchange channel contributes nearly as much as the inelastic channel to the vibrational excitation and de-excitation processes and that the total rate constants pertaining to the purely inelastic processes are largely of the same magnitude as those obtained when both inelastic and reactive channels are included in the dynamics. The inelastic rovibrational rate coefficients involving this astrophysical cation are also found to be much larger than those obtained for anions present in similar interstellar environments.

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