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1.
Nat Immunol ; 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38745085

RESUMEN

The etiology and effect of age-related immune dysfunction in cancer is not completely understood. Here we show that limited priming of CD8+ T cells in the aged tumor microenvironment (TME) outweighs cell-intrinsic defects in limiting tumor control. Increased tumor growth in aging is associated with reduced CD8+ T cell infiltration and function. Transfer of T cells from young mice does not restore tumor control in aged mice owing to rapid induction of T cell dysfunction. Cell-extrinsic signals in the aged TME drive a tumor-infiltrating age-associated dysfunctional (TTAD) cell state that is functionally, transcriptionally and epigenetically distinct from canonical T cell exhaustion. Altered natural killer cell-dendritic cell-CD8+ T cell cross-talk in aged tumors impairs T cell priming by conventional type 1 dendritic cells and promotes TTAD cell formation. Aged mice are thereby unable to benefit from therapeutic tumor vaccination. Critically, myeloid-targeted therapy to reinvigorate conventional type 1 dendritic cells can improve tumor control and restore CD8+ T cell immunity in aging.

2.
Inorg Chem ; 63(20): 9237-9244, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38722713

RESUMEN

Mixed-donor ligands, such as those containing a combination of O/N or O/S, have been studied extensively for the selective extraction of trivalent actinides, especially Am3+ and Cm3+, from lanthanides during the recycling of used nuclear fuel. Oxygen/sulfur donor ligand combinations also result from the hydrolytic and/or radiolytic degradation of dithiophosphates, such as the Cyanex class of extractants, which are initially converted to monothiophosphates. To understand potential differences between the binding of such degraded ligands to Nd3+ and Am3+, the monothiophosphate complexes [M(OPS(OEt)2)5(H2O)2]2- (M3+ = Nd3+, Am3+) were prepared and characterized by single-crystal X-ray diffraction and optical spectroscopy and studied as a function of pressure up to ca. 14 GPa using diamond-anvil techniques. Although Nd3+ and Am3+ have nearly identical eight-coordinated ionic radii, these structures reveal that while the M-O bond distances in these complexes are almost equal, the M-S distances are statistically different. Moreover, for [Nd(OPS(OEt)2)5(H2O)2]2-, the hypersensitive 4I9/2 → 4G5/2 transition shifts as a function of pressure by -11 cm-1/GPa. Whereas for [Am(OPS(OEt)2)5(H2O)2]2-, the 7F0 → 7F6 transition shows a slightly stronger pressure dependence with a shift of -13 cm-1/GPa and also exhibits broadening of the 5f → 5f transitions at high pressures. These data likely indicate an increased involvement of the 5f orbitals in bonding with Am3+ relative to that of Nd3+ in these complexes.

4.
Artículo en Inglés | MEDLINE | ID: mdl-38648896

RESUMEN

OBJECTIVES: To validate the efficacy and safety of withholding antimicrobial therapy in a new cohort of children with cancer and febrile neutropenia (FN) having a demonstrated viral respiratory tract infection. METHODS: Prospective, multicenter, noninferiority, randomized study, approved by the ethical committee, in children presenting with FN at seven hospitals in Chile, evaluated at admission for diagnosis of bacterial and viral pathogens. Children who were positive for a respiratory virus, negative for a bacterial pathogen, and had a favourable evolution after 48-72 hours of antimicrobial therapy were randomized to either maintain or withhold antimicrobial therapy. The primary endpoint was the percentage of episodes with an uneventful resolution, whereas the secondary endpoints were days of fever, days of hospitalization, requirement of antimicrobial treatment readministration, sepsis, paediatric intensive care unit admission, and death. RESULTS: A total of 301 of 939 children with FN episodes recruited between March 2021 and December 2023 had a respiratory virus as a unique identified microorganism, of which 139 had a favourable evolution at 48-72 hours and were randomized, 70 to maintain and 69 to withdraw antimicrobial therapy. The median days of antimicrobial therapy was 5 (IQR 3-6) versus 3 (IQR 3-6) days (p < 0.001), with similar frequency of uneventful resolution 66/70 (94%) and 66/69 (96%); relative risk, 1.01; (95% CI, 0.93 to 1.09), absolute risk difference 0.01; (95% CI, -0.05 to 0.08) and similar number of days of fever and days of hospitalization. No cases of sepsis, paediatric intensive care unit admission, or death were reported. DISCUSSION: We validated the strategy of withdrawal antimicrobial therapy in children with FN and viral respiratory tract infection based on clinical and microbiological/molecular diagnostic criteria. This will enable advances in antimicrobial stewardship strategies with a possible future impact on antimicrobial resistance.

5.
Arch Dis Child ; 109(6): 510-514, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38589198

RESUMEN

BACKGROUND: While research indicates comparable quality of life (QOL) in congenital diaphragmatic hernia (CDH) and healthy populations, the effect of CDH severity on patients' health perceptions remains unexplored. We aimed to assess QOL perception in CDH, hypothesising a decline correlated with increased disease severity. METHODS: In this prospective observational study, we analysed patients with CDH aged 5 years and above participating in a longitudinal outpatient programme. We excluded bilateral CDH, genetic/syndromic conditions, prematurity and late diagnosis. Participants self-administered the age-adapted Pediatric Quality of Life Inventory (PedsQL) survey, covering four domains (physical, emotional, social, school). After enrolment, data were collected blind to severity status (larger defects denoting significant/'severe' disease). Repeated measurements were managed using a random mixed-effects model. RESULTS: Of 34 participants (50% males) who completed the PedsQL, 10 provided measurements at two visits. Eight required a patch (type C), while 26 had primary repairs (type A=8; type B=18). Age at first evaluation was comparable across groups (no patch: median 11 (7-16), patch: 13 (8-15) years, p=0.78). Severe CDH correlated significantly with lower PedsQL scores (adjusted ß: -18%, 95% CI -28%; -7%, adjusted for age at visit and sex). Lower scores specifically occurred in walking, exercising, social and academic functioning. CONCLUSION: Severe CDH significantly lowers QOL. This finding is crucial for resource allocation in long-term CDH health surveillance and advocates for regular inclusion of patient experiences in quality improvement efforts.


Asunto(s)
Hernias Diafragmáticas Congénitas , Calidad de Vida , Índice de Severidad de la Enfermedad , Humanos , Hernias Diafragmáticas Congénitas/psicología , Masculino , Femenino , Estudios Prospectivos , Adolescente , Niño , Preescolar
6.
Am J Perinatol ; 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38569505

RESUMEN

OBJECTIVE: Fetal diagnosis of coarctation of the aorta (CoA) is currently associated with a high false-positive rate. Many predictive markers may be gestational age (GA)-specific. We sought to establish GA-specific traditional and speckle-tracking fetal echocardiography (STE) markers predictive of true CoA in neonates with prenatal suspicion. STUDY DESIGN: This is a retrospective case-control study. We compared the fetal ventricular and arch dimensions, as well as the deformation parameters by STE, of infants who required a postnatal intervention for their CoA with those who did not. Cohort was stratified based on GA before or after 30 weeks. Data extractors were masked to the outcome. The first fetal echocardiogram available was used. RESULTS: Seventy-five newborns with a fetal echocardiography performed between October 2013 and May 2022 for an antenatal suspicion of CoA were included, of which 59 (79%) had an aortic arch with nonsignificant obstruction upon ductal closure, and 16 (21%) underwent a neonatal intervention for a confirmed CoA. Before 30 weeks' GA, the right ventricular to left ventricular (RV/LV) end-diastolic width and end-diastolic area (EDA) ratios were most associated with postnatal CoA confirmation (area under the curve [AUCs] = 0.96 and 0.92). After 30 weeks' GA, the RV/LV end-diastolic width ratio (AUC = 0.95), the Z-score for the ascending aorta (AUC = 0.93), and the LV end-diastolic width Z-score (AUC = 0.91) performed the best. A decreased RV peak longitudinal strain was observed in those who developed true CoA and performed well by receiver operating characteristic analysis after 30 weeks (AUC = 0.85). In the overall cohort, the RV/LV EDA ratio was the most sensitive predictor of CoA and identified all cases with CoA. Indeed, a cutoff > 1.24 had a specificity of 69.5% and a sensitivity of 100% (receiver operating characteristic curve with an AUC of 0.88). CONCLUSION: We outlined sensitive and specific fetal markers associated with postnatal CoA based on GA at suspicion. KEY POINTS: · Fetal ventricular disproportion predicts postnatal coarctation.. · A decreased right ventircular contraction was observed in those with coarctation.. · Fetal markers differ based on gestational age at fetal evaluation..

7.
J Am Chem Soc ; 146(11): 7822-7830, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38456811

RESUMEN

Understanding the effects of pressure on actinide compounds is an integral part of safe nuclear waste storage in deep geologic repositories and provides a means of systematically altering the structure and properties. However, detailing how the effects of pressure evolve across the actinide series in the later elements is not typically undertaken because of the challenges of conducting research on these unstable isotopes. Here, a family of bimetallic actinide complexes, [(An(pmtz)2(H2O)3)2(µ-pmtz)]2(pmtz)2·nH2O (An3+ = Cm3+, Bk3+, and Cf3+, pmtz- = 5-(pyrimidyl)tetrazolate; Cm1, Bk1, and Cf1), are reported and represent the first structurally characterized bimetallic berkelium and californium compounds. The pressure response as determined from UV-vis-NIR transitions varies for Cm1, Bk1, and Cf1. The 5f → 5f transitions in Cm1 are notably more sensitive to pressure compared to those in Bk1 and Cf1 and show substantial bathochromic shifting of several 5f → 5f transitions. In the case of Bk1, an ingrowth of a metal-to-ligand charge-transfer transition occurs at elevated pressures because of the accessible Bk3+/Bk4+ couple. For Cf1, no substantial transition shifting or emergence of MLCT transitions is observed at elevated pressures because of the prohibitive energetics of the Cf3+/Cf4+ couple and reduced sensitivity of the 5f → 5f transitions to the local coordination environment because of the more contracted 5f shell versus Cm3+ and Bk3+.

8.
J Fish Biol ; 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38420688

RESUMEN

Knowledge of thermal tolerance limits provides important clues to the capacity of a species to withstand acute and chronic thermal changes. Climate models predict the increase and intensification of events such as heat waves, therefore understanding the upper thermal limits that a species can tolerate has become of utmost importance. We measured the upper thermal tolerance of the endemic Magdalena river stingray Potamotrygon magdalenae acclimated to experimental conditions, and then used critical thermal methodology to find the temperature at which an organism reaches a critical endpoint where locomotory activity becomes disorganized and the animal loses its ability to escape from conditions that will promptly lead to its death. We also describe the behavioral response of individuals to acute thermal stress and infer the possible consequences of temperature increases in the habitats of P. magdalenae populations. There were no significant differences between sexes in temperature tolerance or behavior. The critical thermal maximum (39°C) was 5.9°C above the maximum recorded temperature for the study area. Although P. magdalenae was tolerant to high temperature and currently is not living at its upper thermal limit, its survival in Guarinocito Pond will be threatened if temperatures continue to increase, considering the warming scenarios predicted for tropical regions due to climate change, even including short-term climate phenomena such as El Niño.

9.
Inorg Chem ; 63(2): 1266-1273, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38165641

RESUMEN

The salt metathesis reaction of Na(pmtz)·H2O [pmtz- = 5-(pyrimidyl)tetrazolate] and PuBr3·nH2O in an aqueous media leads to the formation of the mononuclear compound [Pu(pmtz)3(H2O)3]·(3 + n) H2O (Pu1, n = ∼8) that is isotypic with the lanthanide compounds [Ln(pmtz)3(H2O)3]·(3 + n) H2O (Ln = Ce-Nd). Dissolution and recrystallization of Pu1 in water yields the dinuclear compound {[Pu(pmtz)2(H2O)3]2(µ-pmtz)}2(pmtz)2·14H2O (Pu2), which is isotypic with the lanthanide compounds {[Ln(pmtz)2(H2O)3]2(µ-pmtz)}2(pmtz)2·14H2O (Ln = Nd and Sm). Like their nine-coordinate ionic radii, the M-O and M-N bond lengths in Pu1/Pu2 and Nd1/Nd2, respectively, are within error of one another. The Laporte-forbidden 4f → 4f and 5f → 5f transitions are also assigned in the UV-vis-NIR spectra for these f-element tetrazolate coordination compounds.

10.
Pediatr Infect Dis J ; 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38063512

RESUMEN

BACKGROUND: The collection of blood cultures (BC) is key for guiding antimicrobial therapy in children with febrile neutropenia (FN), more than 90% have central venous catheters (CVC). There is no consensus on the need for peripheral BC over central BC in this population. The aim of this study was to determine the contribution of peripheral BC over central BC in the diagnosis of bloodstream infections in children with FN. METHODS: Descriptive, retrospective study, episodes of FN recorded prospectively in 6 hospitals in Santiago, Chile, from 2016 to 2021. Central and peripheral BC were drawn upon admission. All episodes with at least one (+) BC were allocated to one of these groups: consistent (+) BC, inconsistent (+) BC, only CVC (+) BC and only peripheral (+) BC. The volume of the samples was recorded. RESULTS: The analysis included 241 episodes of FN with at least one (+) BC. The median age was 7.2 years, 51% were female, 84% had hematological cancer and 98% had episodes of high-risk FN. Of a total of 241 episodes, 135 (56%) had consistent (+) BC, 13 (5%) had inconsistent (+) BC, 35 (15%) had only CVC (+) BC and 58 (24%) had only peripheral (+) BC. There were no significant differences in the volume of the samples between central and peripheral BC. CONCLUSIONS: The proportion of bloodstream infections detected only through peripheral BC was 24%, higher than previously reported, not due to sample volume. We recommend obtaining peripheral as well CVC BC in children with FN.

11.
Inorg Chem ; 62(38): 15375-15381, 2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37700461

RESUMEN

High external pressure is found to induce a non-coordinated water molecule to bond to cerium in a previously studied mellitate coordination polymer, as determined by high-pressure single-crystal X-ray diffraction, resulting in a coordination number transition at 3.85 GPa from 9 to 9.5 where half the cerium ions are 10-coordinate. Also, bond length changes due to increased pressure are experimentally measured, whereas the cerium-carboxylate bond lengths overall change by -0.004(9) Å/GPa, the cerium-water bonds by -0.016(3) Å/GPa, and cerium-oxygen bonds overall by -0.010(6) Å/GPa, which corresponds well with theoretical bond length decreases determined for similar compounds. The high-pressure absorbance spectra of the analogous neodymium mellitate are examined and compared with the structural changes observed.

12.
Life Sci ; 331: 122065, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37659591

RESUMEN

Head and neck cancer is a major health problem worldwide, with most cases arising in the oral cavity. Oral squamous cell carcinoma (OSCC) is the most common type of oral cancer, accounting for over 90% of all cases. Compared to other types of cancer, OSCC, has the worse prognosis, with a 5-year survival rate of 50%. Additionally, OSCC is characterized by a high rate of resistance to chemotherapy treatment, which may be partly explained by the presence of cancer stem cells (CSC) subpopulation. CSC can adapt to harmful environmental condition and are highly resistant to both chemotherapy and radiotherapy treatments, thus contributing to tumor relapse. The aim of this review is to highlight the role of mitochondria in oral CSC as a potential target for oral cancer treatment. For this purpose, we reviewed some fundamental aspects of the most validated protein markers of stemness, autophagy, the mitochondrial function and energy metabolism in oral CSC. Moreover, a discussion will be made on why energy metabolism, especially oxidative phosphorylation in CSC, may offer such a diverse source of original pharmacological target for new drugs. Finally, we will describe some drugs able to disturb mitochondrial function, with emphasis on those aimed to interrupt the electron transport chain function, as novel therapeutic strategies in multidrug-resistant oral CSC. The reutilization of old drugs approved for clinical use as new antineoplastics, in cancer treatment, is also matter of revision.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Humanos , Neoplasias de la Boca/tratamiento farmacológico , Carcinoma de Células Escamosas de Cabeza y Cuello , Mitocondrias , Células Madre Neoplásicas
13.
Rev. chil. infectol ; 40(4)ago. 2023.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1521851

RESUMEN

Introducción: La infección fúngica invasora (IFI) es una causa importante de morbilidad y mortalidad en pacientes oncológicos pediátricos y portadores de aplasia medular (AM) severa. Objetivo: Describir la epidemiología de la IFI desde el año 2016 al 2020 en niños con cáncer y AM para evaluar la necesidad de profilaxis antifúngica. Métodos: Estudio retrospectivo, multicéntrico, en pacientes pediátricos con cáncer y AM severa. Se incluyeron IFI probables y probadas. Resultados: Se diagnosticaron 57 casos de IFI, mediana de edad 9 años, 70% probadas y 30% probables. Hubo 42% de infecciones por levaduras y 56% por hongos filamentosos. Los sitios de infección más frecuentes fueron pulmón 38%, sangre 36% y rinosinusal 21%. La frecuencia global fue 5,4%; de ellas 21% en AM severa, 10% en leucemia mieloide aguda (LMA), 6,9% en recaída de LMA, 5,4% en recaída de leucemia linfática aguda (LLA), 3,8% en LLA. Las infecciones por hongos filamentosos predominaron en LMA, recaída de LMA. y AM severa. La mortalidad en pacientes con IFI fue de 11%. Conclusión: La frecuencia de IFI concuerda con la literatura médica. Recomendamos profilaxis antifúngica contra hongos filamentosos en pacientes con AM severa, LMA y recaída de LMA. Considerar en recaída de LLA de alto riesgo en etapa de inducción.


Background: Invasive fungal infections (IFIs) are an important cause of morbidity and mortality in pediatric oncology patients and severe aplastic anemia (SAA). Aim: To describe the epidemiology of IFI from 2016 to 2020 in children with cancer and SAA to assess the indication of antifungal prophylaxis. Methods: Multicenter, retrospective study of IFIs in pediatric oncology patients and SAA. Probable and proven IFIs were included. Results: Over the 5-year period, 57 IFIs were found, median age 9 years, 70% were proven and 30% were probable. Yeast infections were 42% and mold infections 56%. The most frequent infection sites were lung 38%, blood 36% and rhinosinusal 21%. The total IFI frequency was 5.4%, 21% in SAA, 10% in acute myeloid leukemia (AML), 6.9% in relapsed AML, 5.4% in relapsed acute lymphoblastic leukemia (ALL), 3.8% in ALL. Mold infections were predominant in AML, relapsed AML, and SAA. IFIs mortality was 11%. Conclusion: Frequency of IFI was consistent with the literature. We strongly recommend antifungal prophylaxis against mold infections in patients with SAA, AML, and relapsed AML. Would consider in high risk ALL relapse in induction chemotherapy.

14.
Inorg Chem ; 62(32): 12905-12912, 2023 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-37523261

RESUMEN

N,N,N',N'-tetramethyl diglycolamide (TMDGA), a methylated variant of the diglycolamide extractants being proposed as curium holdback reagents in advanced used nuclear fuel reprocessing technologies, has been crystallized with plutonium, a transuranic actinide that has multiple accessible oxidation states. Two plutonium TMDGA complexes, [PuIII(TMDGA)3][PuIII(NO3)6] and[PuIV(TMDGA)3][PuIV(NO3)6]2·0.75MeOH, were crystallized through solvent diffusion of a reaction mixture containing plutonium(III) nitrate and TMDGA. The sample was then partially oxidized by air to yield [PuIV(TMDGA)3][PuIV(NO3)6]2·0.75MeOH. Single-crystal X-ray diffraction reveals that the multinuclear systems crystallize with hexanitrato anionic species, providing insight into the first solid-state isolation of the elusive trivalent plutonium hexanitrato species. Crystallography data show a change in geometry around the TMDGA metal center from Pu3+ to Pu4+, with the symmetry increasing approximately from C4v to D3h. These complexes provide a rare opportunity to investigate the bond metrics of plutonium in two different oxidation states with similar coordination environments. Further, these new structures provide insight into the potential chemical and structural differences arising from the radiation-induced formation of transient tetravalent curium oxidation states in used nuclear fuel reprocessing streams.

15.
J Mol Graph Model ; 124: 108564, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37453311

RESUMEN

PURPOSE OR OBJECTIVE: Melanoma is one of the most dangerous forms of skin cancer and the discovery of novel drugs is an ongoing effort. Quantitative Structure Activity Relationship (QSAR) is a computational method that allows the estimation of the properties of a molecule, including its biological activity. QSAR models have been widely employed in the search for potential drug candidates, but also for agrochemicals and other molecules with applications in different branches of the industry. Here we present Bambu, a simple command line tool to generate QSAR models from high-throughput screening bioassays datasets. METHODS: The tool was developed using the Python programming language and relies mainly on RDKit for molecule data manipulation, FLAML for automated machine learning and the PubChem REST API for data retrieval. As a proof-of-concept we have employed the tool to generate QSAR models for melanoma cell growth inhibition based on HTS data and used them to screen libraries of FDA-approved drugs and natural compounds. Additionally, Bambu was compared to QSAR-Co, another automated tool for QSAR model generation. RESULTS: based on the developed tool we were able to produce QSAR models and identify a wide variety of molecules with potential melanoma cell growth inhibitors, many of which with anti-tumoral activity already described. The QSAR models are available through the URL http://caramel.ufpel.edu.br, and all data and code used to generate its models are available at Zenodo (https://doi.org/10.5281/zenodo.7495214). Bambu source code is available at GitHub (https://github.com/omixlab/bambu-v2). In the benchmark, Bambu was able to produce models with higher accuracy, recall, F1 and ROC AUC when compared to QSAR-Co for the selected datasets. CONCLUSIONS: Bambu is an free and open source tool which facilitates the creation of QSAR models and can be futurely applied in a wide variety of drug discovery projects.


Asunto(s)
Descubrimiento de Drogas , Melanoma , Humanos , Descubrimiento de Drogas/métodos , Programas Informáticos , Ensayos Analíticos de Alto Rendimiento , Aprendizaje Automático , Melanoma/tratamiento farmacológico , Relación Estructura-Actividad Cuantitativa
17.
J Pediatr ; 261: 113585, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37354991

RESUMEN

We evaluated the association between left cardiac 3-dimensional echocardiographic parameters and brain injury in a single-center prospective study of neonates with neonatal encephalopathy. On day 2 of life, neonates with brain injury had greater left ventricle end-diastolic and stroke volume but also greater peak global circumferential strain detected by 3-dimensional echocardiogram.


Asunto(s)
Lesiones Encefálicas , Ecocardiografía Tridimensional , Disfunción Ventricular Izquierda , Recién Nacido , Humanos , Lactante , Función Ventricular Izquierda , Estudios Prospectivos , Ecocardiografía/métodos , Ecocardiografía Tridimensional/métodos , Volumen Sistólico , Ventrículos Cardíacos/diagnóstico por imagen , Lesiones Encefálicas/complicaciones , Lesiones Encefálicas/diagnóstico por imagen , Disfunción Ventricular Izquierda/diagnóstico por imagen
18.
MycoKeys ; 96: 143-157, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37214179

RESUMEN

Fungal metabarcoding of substrates such as soil, wood, and water is uncovering an unprecedented number of fungal species that do not seem to produce tangible morphological structures and that defy our best attempts at cultivation, thus falling outside the scope of the International Code of Nomenclature for algae, fungi, and plants. The present study uses the new, ninth release of the species hypotheses of the UNITE database to show that species discovery through environmental sequencing vastly outpaces traditional, Sanger sequencing-based efforts in a strongly increasing trend over the last five years. Our findings challenge the present stance of some in the mycological community - that the current situation is satisfactory and that no change is needed to "the code" - and suggest that we should be discussing not whether to allow DNA-based descriptions (typifications) of species and by extension higher ranks of fungi, but what the precise requirements for such DNA-based typifications should be. We submit a tentative list of such criteria for further discussion. The present authors hope for a revitalized and deepened discussion on DNA-based typification, because to us it seems harmful and counter-productive to intentionally deny the overwhelming majority of extant fungi a formal standing under the International Code of Nomenclature for algae, fungi, and plants.

19.
Inorg Chem ; 62(22): 8478-8481, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37210659

RESUMEN

The crystallization, single crystal structure, and Raman spectroscopy of Ra(NO3)2 have been investigated by experimentation and theory, which represent the first pure radium compound characterized by single crystal X-ray diffraction. The Ra2+ centers are bound by six chelating nitrate anions to form an anticuboctahedral geometry. The Raman spectrum acquired from a single crystal of Ra(NO3)2 generally occurs at a lower frequency than found in Ba(NO3)2, as expected. Computational studies on Ra(NO3)2 provide an estimation of the bond orders via Wiberg bond indices and indicate that Ra-O interactions are weak with values of 0.025 and 0.026 for Ra-O bonds. Inspection of natural bond orbitals and natural localized molecular orbitals suggest negligible orbital mixing. However, second-order perturbation interactions show that donation from the lone pairs of the nitrate oxygen atoms to the 7s orbitals of Ra2+ stabilizes each Ra-O interaction by ca. 5 kcal mol-1.

20.
Indian J Dermatol Venereol Leprol ; 89(5): 725-728, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37067140

RESUMEN

Background People affected by Human Immunodeficiency Virus (HIV), are burdened by a higher risk of developing malignancies including non-melanoma skin cancer (NMSC) and melanoma skin cancer. Objective To evaluate the association of HIV with melanoma and NMSC at a University Hospital. Methods This is a cross-sectional retrospective study of HIV-infected and a matched comparison group, analyzing the associations between skin cancer and HIV infection. Results Compared to the HIV-uninfected, HIV-infected had 80% association with skin cancer (CI 95%: 1.3-2.4, P = 0.001) The risk was 45-fold higher by patients" age (CI 95%: 3.3-15.9: P = 0.001). When adjusted for patient age, sex and race, the risk was 6.4 fold ligher of having cancer if compared to the others (CI 95%: 49-84, P = 0.001). Melanoma was not found in HIV-infected. Conclusion With this study, we have demonstrated that HIV-infected patients have an increased risk of BCC and SCC. Preventive dermatologic management is pivotal in the care of immunosuppressed patients. These patients must undergo the dermatological examination annually and should receive extensive counseling regarding sun avoidance, use of sunscreens,and sun-protective clothing.


Asunto(s)
Carcinoma Basocelular , Carcinoma de Células Escamosas , Infecciones por VIH , Melanoma , Neoplasias Cutáneas , Humanos , Infecciones por VIH/complicaciones , Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología , Carcinoma Basocelular/complicaciones , Estudios Retrospectivos , Estudios Transversales , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/epidemiología , Carcinoma de Células Escamosas/etiología , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/epidemiología , Neoplasias Cutáneas/etiología , Melanoma/diagnóstico , Melanoma/epidemiología , Melanoma/complicaciones , Factores de Riesgo
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