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1.
Eur J Ophthalmol ; 34(3): NP1-NP4, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38403966

RESUMO

INTRODUCTION: Congenital Central Hypoventilation Syndrome (CCHS) is a rare disease due to a severely impaired central control of breathing and dysfunction of the autonomic nervous system. Ophthalmologic abnormalities are common in patients with CCHS and include horizontal strabismus, pupil and iris abnormalities and ptosis. We report a unique case of CCHS in association with monocular elevation deficit (MED) in a boy diagnosed with CCHS at birth. CASE DESCRIPTION: We report a case of a boy with a confirmed diagnosis of CCHS (complete sequencing of the paired-like homeobox 2b (PHOX2B) gene) after presenting little respiratory effort and cyanosis at birth. The ophthalmological examination shows an impaired elevation of the left eye, both in adduction and abduction, associated with mild and variable left ptosis. His mother has observed that the left eyelid elevates when the child feeds. A deviation in the primary gaze position or a chin-up position are not present. The funduscopic examination is normal. Given that deviation is limited to upgaze, the ptosis is mild and the patient's age, observation is decided. CONCLUSIONS: Ophthalmologic abnormalities are common in patients with CCHS and include horizontal strabismus, pupil and iris abnormalities and ptosis. To the best of our knowledge, this is the first report of MED in association with CCHS. Further studies are needed to determine if an association between MED and CCHS exists or is just a casual finding in this case.


Assuntos
Blefaroptose , Hipoventilação , Hipoventilação/congênito , Apneia do Sono Tipo Central , Humanos , Masculino , Hipoventilação/diagnóstico , Hipoventilação/genética , Hipoventilação/fisiopatologia , Blefaroptose/diagnóstico , Blefaroptose/congênito , Blefaroptose/fisiopatologia , Apneia do Sono Tipo Central/diagnóstico , Apneia do Sono Tipo Central/fisiopatologia , Apneia do Sono Tipo Central/genética , Proteínas de Homeodomínio/genética , Recém-Nascido , Fatores de Transcrição/genética , Estrabismo/diagnóstico , Estrabismo/fisiopatologia
2.
Nanoscale Horiz ; 7(6): 607-615, 2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35389405

RESUMO

The synthesis of metallic nanoparticles (MNP) with high surface area and controlled shape is of paramount importance to increase their catalytic performance. The detailed growing process of NP is mostly unknown and understanding the specific steps would pave the way for a rational synthesis of the desired MNP. Here we take advantage of the stabilization properties exerted by the tetragonal prismatic supramolecular nanocapsule 8·(BArF)8 to develop a synthetic methodology for sub-nanometric RuNP (0.6-0.7 nm). The catalytic properties of these sub-nanometric nanoparticles were tested on the hydrogenation of styrene, obtaining excellent selectivity for the hydrogenation of the alkene moiety. In addition, the encapsulation of [Ru5] clusters inside the nanocapsule is strikingly observed in most of the experimental conditions, as ascertained by HR-MS. Moreover, a thorough DFT study enlightens the nature of the [Ru5] clusters as tb-Ru5H2(η6-PhH)2(η6-pyz)3 (2) trapped by two arene moieties of the clip, or as tb-Ru5H2(η1-pyz)6(η6-pyz)3 (3) trapped between the two Zn-porphyrin units of the nanocapsule. Both options fulfill the Wade-Mingos counting rules, i.e. 72 CVEs for the closotb. The trapped [Ru5] metallic clusters are proposed to be the first-grown seeds of subsequent formation of the subnanometric RuNP. Moreover, the double role of the nanocapsule in stabilising ∼0.7 nm NPs and also in hosting ultra-small Ru clusters, is unprecedented and may pave the way towards the synthesis of ultra-small metallic clusters for catalytic purposes.

3.
Nat Chem ; 13(5): 420-427, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33859394

RESUMO

Molecular Russian dolls (matryoshkas) have proven useful for testing the limits of preparative supramolecular chemistry but applications of these architectures to problems in other fields are elusive. Here we report a three-shell, matryoshka-like complex-in which C60 sits inside a cycloparaphenylene nanohoop, which in turn is encapsulated inside a self-assembled nanocapsule-that can be used to address a long-standing challenge in fullerene chemistry, namely the selective formation of a particular fullerene bis-adduct. Spectroscopic evidence indicates that the ternary complex is sufficiently stable in solution for the two outer shells to affect the addition chemistry of the fullerene guest. When the complex is subjected to Bingel cyclopropanation conditions, the exclusive formation of a single trans-3 fullerene bis-adduct was observed in a reaction that typically yields more than a dozen products. The selectivity facilitated by this matryoshka-like approach appears to be a general phenomenon and could be useful for applications where regioisomerically pure C60 bis-adducts have been shown to have superior properties compared with isomer mixtures.

4.
J Am Chem Soc ; 142(37): 16051-16063, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32822170

RESUMO

The dynamic adaptability of tetragonal prismatic nanocapsule 18+ in the selective separation of fullerenes and endohedral metallofullerenes (EMFs) remains unexplored. Therefore, the essential molecular details of the fullerene recognition and binding process into the coordination capsule and the origins of fullerene selectivity remain elusive. In this work, the key steps of fullerene recognition and binding processes have been deciphered by designing a protocol which combines 1H-1H exchange spectroscopy (2D-EXSY) NMR experiments, long time-scale Molecular Dynamics (MD) and accelerated Molecular Dynamics (aMD) simulations, which are combined to completely reconstruct the spontaneous binding and unbinding pathways from nanosecond to second time-range. On one hand, binding (k'on) and unbinding (koff) rate constants were extracted from 1H-1H exchange spectroscopy (EXSY) NMR experiments for both C60 and C70. On the other hand, MD and aMD allowed monitoring the molecular basis of the encapsulation and guest competition processes at a very early stage under nonequilibrium conditions. The receptor capsule displays dynamical adaptability features similar to those observed in the process of biomolecular recognition in proteins. In addition, the encapsulation of bis-aza[60]fullerene (C59N)2 within a supramolecular coordination capsule has been studied for the first time, showcasing the pros and cons of the dumbbell-shaped guest in the dynamics of the encapsulation process and in the stability of the final bound adduct. The powerful combination of NMR, MD, and aMD methodologies allows to obtain a precise picture of the subtle events directing the encapsulation and is thus a predictive tool for understanding host-guest encapsulation and interactions in numerous supramolecular systems.

5.
Chem Commun (Camb) ; 55(6): 798-801, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30570641

RESUMO

A novel naphthalene-based 5·(BArF)8 capsule allows for the size-selective inclusion of C60 from fullerene mixtures. Its size selectivity towards C60 has been rationalized by its dynamic adaptability in solution that has been investigated by molecular dynamics. Additionally, 5·(BArF)8 encapsulates C60-derivatives such as C60-PCBM and N-methylpyrrolidine-C60. The latter can be separated from C60 since 5·(BArF)8 displays distinct affinity for them.

6.
Angew Chem Int Ed Engl ; 57(35): 11294-11299, 2018 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-29917307

RESUMO

Supramolecular nanocapsule 1⋅(BArF)8 is able to sequentially and selectively entrap recently discovered U2 @C80 and unprecedented Sc2 CU@C80 , simply by soaking crystals of 1⋅(BArF)8 in a toluene solution of arc-produced soot. These species, selectively and stepwise absorbed by 1⋅(BArF)8 , are easily released, obtaining highly pure fractions of U2 @C80 and Sc2 CU@C80 in one step. Sc2 CU@C80 represents the first example of a mixed metal actinide-based endohedral metallofullerene (EMF). Remarkably, the host-guest studies revealed that 1⋅(BArF)8 is able to discriminate EMFs with the same carbon cage but with different encapsulated cluster and computational studies provide support for these observations.

7.
Inorg Chem ; 57(7): 3529-3539, 2018 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-29293325

RESUMO

The encapsulation of coordination complexes in a tetragonal prismatic nanocage (1·(BArF)8) built from Zn-porphyrin and macrocyclic Pd-clip-based synthons is described. The functional duality of the guest ligand L1 allows for its encapsulation inside the cage 1·(BArF)8, along with the simultaneous coordination of ZnII, CuII, or FeIII metal ions. Remarkably, the coordination chemistry inside the host-guest adduct L1⊂1·(BArF)8 occurs in both solution solution and solid state. The resulting confined metallocomplexes have been characterized by means of UV-vis, ESI-HRMS, NMR, and EPR techniques. Furthermore, the emission of the Zn-porphyrin fluorophores of 1·(BArF)8 is strongly quenched by the encapsulation of paramagnetic complexes, representing a remarkable example of guest-dependent tuning of the host fluorescence.

8.
Chemistry ; 23(15): 3553-3557, 2017 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-28135408

RESUMO

A self-assembled CuII -based nanocapsule enables efficient and straightforward isolation of Sc3 N@C80 from arc-processed raw soot. The newly designed CuII -based supramolecular nanocapsule 5⋅(OTf)8 was used to effectively entrap fullerenes and endohedral metallofullerenes (EMFs) with different affinities depending on their size and shape. Moreover, we took advantage of the sharply different entrapment abilities of the 5⋅(OTf)8 cage in the solid state versus in solution to encapsulate all the species with the exception of Sc3 N@C80 (both Ih and D5h isomers), which remains pure in solution. HPLC quantification determined that up to 85 % of the total Sc3 N@C80 content in the initial mixture was recovered in very high purity (>99.5 %). The complete release of the encapsulated species with an orthogonal solvent-washing strategy regenerates 5⋅(OTf)8 ready to be re-used. This approach opens new opportunities for EMFs purification.

10.
Chem Soc Rev ; 45(1): 40-62, 2016 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-26456881

RESUMO

Fullerene extracts are easily available from fullerene soot, but finding an efficient strategy to obtain them in pure form remains elusive, especially for higher fullerenes (Cx, x > 70). The properties of the latter remain unclear and their potential application to multiple research fields has not been developed mainly due to their purification difficulties. In this Tutorial Review we cover the use of molecular receptors for the separation of fullerenes by means of host-guest interactions. This strategy allows gaining selectivity, no specialized equipment is required and, ideally, recyclable systems can be designed. We focus on the metallosupramolecular receptors using the metal-ligand coordination approach, which offers a controlled and versatile strategy to design fullerene hosts, and the latest strategies to release the fullerene guest will be described. The field is probably in its beginnings but it is rapidly evolving and we are confident that this tutorial review will help researchers to rapidly gain a general overview of the main works and concepts that are leading this promising strategy and that may lead towards a useful methodology to purify fullerenes.


Assuntos
Fulerenos/química , Compostos Organometálicos/química , Sítios de Ligação , Cristalografia por Raios X , Fulerenos/isolamento & purificação , Ligantes , Substâncias Macromoleculares/química , Modelos Moleculares , Estrutura Molecular
11.
J Am Chem Soc ; 137(7): 2680-7, 2015 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-25632976

RESUMO

Regio- and enantioselective hydroformylation of styrenes is attained upon embedding a chiral Rh complex in a nonchiral supramolecular cage formed from coordination-driven self-assembly of macrocyclic dipalladium complexes and tetracarboxylate zinc porphyrins. The resulting supramolecular catalyst converts styrene derivatives into aldehyde products with much higher chiral induction in comparison to the nonencapsulated Rh catalyst. Spectroscopic analysis shows that encapsulation does not change the electronic properties of the catalyst nor its first coordination sphere. Instead, enhanced enantioselectivity is rationalized by the modification of the second coordination sphere occurring upon catalyst inclusion inside the cage, being one of the few examples in achieving an enantioselective outcome via indirect through-space control of the chirality around the catalyst center. This effect resembles those taking place in enzymatic sites, where structural constraints imposed by the enzyme cavity can impart stereoselectivities that cannot be attained in bulk. These results are a showcase for the future development of asymmetric catalysis by using size-tunable supramolecular capsules.


Assuntos
Aldeídos/química , Ródio/química , Estireno/química , Amidas/química , Catálise , Modelos Moleculares , Conformação Molecular , Ácidos Fosfóricos/química , Estereoisomerismo
12.
Nat Commun ; 5: 5557, 2014 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-25424201

RESUMO

Since fullerenes are available in macroscopic quantities from fullerene soot, large efforts have been geared toward designing efficient strategies to obtain highly pure fullerenes, which can be subsequently applied in multiple research fields. Here we present a supramolecular nanocage synthesized by metal-directed self-assembly, which encapsulates fullerenes of different sizes. Direct experimental evidence is provided for the 1:1 encapsulation of C60, C70, C76, C78 and C84, and solid state structures for the host-guest adducts with C60 and C70 have been obtained using X-ray synchrotron radiation. Furthermore, we design a washing-based strategy to exclusively extract pure C60 from a solid sample of cage charged with a mixture of fullerenes. These results showcase an attractive methodology to selectively extract C60 from fullerene mixtures, providing a platform to design tuned cages for selective extraction of higher fullerenes. The solid-phase fullerene encapsulation and liberation represent a twist in host-guest chemistry for molecular nanocage structures.

13.
Enferm. infecc. microbiol. clín. (Ed. impr.) ; 32(7): 428-433, ago.-sept. 2014. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-125437

RESUMO

INTRODUCCIÓN: Los brotes detectados de campilobacteriosis son poco frecuentes y, por lo general, cursan con un bajo número de pacientes, aunque se estima que muchos más permanecerían sin diagnosticar. Las técnicas de investigación de brotes más exitosas en Campylobacter spp. (PFGE, MLST) tienen el inconveniente de ser laboriosas y no estar disponibles en muchos laboratorios. MÉTODOS: Durante el año 2008 se recibieron 352 aislados de C. jejuni y C. coli procedentes de 16 hospitales. Todas las cepas fueron tipificadas genotípicamente mediante RFLP-PCR-flaA (tipo flaA) y fenotípicamente con su resistotipo. Se estableció que aquellas cepas de la misma especie procedentes del mismo hospital, aisladas en un periodo de hasta 11 días, con valores de CMI de±1 dilución y con el mismo tipo flaA, podrían pertenecer a un brote. Las cepas que cumpliesen con estos criterios serían posteriormente tipificadas mediante KpnI-PFGE y MLST. RESULTADOS: Veintitrés de los 352 aislados, en 10 grupos, cumplían con los criterios de pertenencia a posibles brotes no diagnosticados. En 8 grupos los pulsotipos (PFGE) de los aislados de cada grupo tenían una semejanza entre ellos mayor del 95%. En 7 de ellos los secuenciotipos (MLST) eran coincidentes. CONCLUSIONES: El uso de 2 marcadores sencillos (resistotipo y RFLP-PCR-flaA) puede detectar aislados que probablemente formen parte de un brote de campilobacteriosis no diagnosticado. Para su confirmación se requieren otros marcadores moleculares y los datos epidemiológicos de cada aislado. El estudio apunta a que, como en otros países, el número de brotes de campilobacteriosis en España está probablemente infraestimado


INTRODUCTION: Outbreaks of campylobacteriosis are infrequent and usually involve a low number of patients, although it is estimated that many more remain undiagnosed. The most successful techniques for outbreak investigation in Campylobacter spp. (PFGE, MLST) have the drawback of being laborious and not available in many laboratories. METHODS: During the year 2008, 352 isolates of C. jejuni and C. coli from 16 hospitals were received in our laboratory. All strains were genotyped by RFLP-PCR-flaA (flaA type) and phenotyped with their resistotype. It was established that the strains of the same species from the same hospital, isolated over a period of up to 11 days, with MIC values of±1 dilution with the same flaA type could belong to an outbreak. Strains that met these criteria would be later subtyped by KpnI-PFGE and MLST.RESULTS:A total of 23 out of 352 isolates, distributed in 10 groups, met the criteria for being associated with putative undiagnosed outbreaks. The similarity of the PFGE-profiles in 8 groups was greater than 95% among the isolates from each group. In 7 of the groups, the sequence types (MLST) were coincident. CONCLUSIONS: The use of 2 easy markers (resistotype and RFLP-PCR-flaA) may detect isolates probably belonging to an undiagnosed outbreak of campylobacteriosis. Accurate diagnosis requires other molecular markers and epidemiological data of each isolate. The study suggests that, as in other countries, the number of outbreaks of campylobacteriosis in Spain is probably underestimated


Assuntos
Humanos , Campylobacter/isolamento & purificação , Infecções por Campylobacter/microbiologia , Reação em Cadeia da Polimerase/métodos , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados/métodos , Surtos de Doenças/prevenção & controle , Fatores de Risco , Controle de Doenças Transmissíveis/métodos
14.
Enferm Infecc Microbiol Clin ; 32(7): 428-33, 2014.
Artigo em Espanhol | MEDLINE | ID: mdl-24139336

RESUMO

INTRODUCTION: Outbreaks of campylobacteriosis are infrequent and usually involve a low number of patients, although it is estimated that many more remain undiagnosed. The most successful techniques for outbreak investigation in Campylobacter spp. (PFGE, MLST) have the drawback of being laborious and not available in many laboratories. METHODS: During the year 2008, 352 isolates of C. jejuni and C. coli from 16 hospitals were received in our laboratory. All strains were genotyped by RFLP-PCR-flaA (flaA type) and phenotyped with their resistotype. It was established that the strains of the same species from the same hospital, isolated over a period of up to 11 days, with MIC values of±1 dilution with the same flaA type could belong to an outbreak. Strains that met these criteria would be later subtyped by KpnI-PFGE and MLST. RESULTS: A total of 23 out of 352 isolates, distributed in 10 groups, met the criteria for being associated with putative undiagnosed outbreaks. The similarity of the PFGE-profiles in 8 groups was greater than 95% among the isolates from each group. In 7 of the groups, the sequence types (MLST) were coincident. CONCLUSIONS: The use of 2 easy markers (resistotype and RFLP-PCR-flaA) may detect isolates probably belonging to an undiagnosed outbreak of campylobacteriosis. Accurate diagnosis requires other molecular markers and epidemiological data of each isolate. The study suggests that, as in other countries, the number of outbreaks of campylobacteriosis in Spain is probably underestimated.


Assuntos
Infecções por Campylobacter/diagnóstico , Infecções por Campylobacter/epidemiologia , Campylobacter jejuni/classificação , Campylobacter jejuni/genética , Surtos de Doenças , Flagelina/genética , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Infecções por Campylobacter/microbiologia , Farmacorresistência Bacteriana/genética , Humanos , Espanha/epidemiologia
15.
Chemistry ; 19(4): 1445-56, 2013 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-23212936

RESUMO

The metal-directed supramolecular synthetic approach has paved the way for the development of functional nanosized molecules. In this work, we report the preparation of the new nanocapsule 3·(CF(3)SO(3))(8) with a A(4 B(2) tetragonal prismatic geometry, where A corresponds to the dipalladium hexaazamacrocyclic complex Pd-1, and B corresponds to the tetraanionic form of palladium 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin (2). The large void space of the inner cavity and the supramolecular affinity for guest molecules towards porphyrin-based hosts converts this nanoscale molecular 3D structure into a good candidate for host-guest chemistry. The interaction between this nanocage and different guest molecules has been studied by means of NMR, UV/Vis, ESI-MS, and DOSY experiments, from which highly selective molecular recognition has been found for anionic, planar-shaped π guests with association constants (K(a)) higher than 10(9) M(-1) , in front of non-interacting aromatic neutral or cationic substrates. DFT theoretical calculations provided insights to further understand this strong interaction. Nanocage 3·(CF(3)SO(3))(8) can not only strongly host one single molecule of M(dithiolene)(2) complexes (M=Au, Pt, Pd, and Ni), but also can finely tune their optical and redox properties. The very simple synthesis of both the supramolecular cage and the building blocks represents a step forward for the development of polyfunctional supramolecular nanovessels, which offer multiple applications as sensors or nanoreactors.

16.
Enferm Infecc Microbiol Clin ; 24(7): 437-9, 2006.
Artigo em Espanhol | MEDLINE | ID: mdl-16956532

RESUMO

INTRODUCTION: The aim of this study is to describe an outbreak of diarrhea caused by Campylobacter jejuni in a primary school. METHODS: Stool samples from five patients were cultured. Molecular typing of the isolated strains was performed using PCR-RFLP-flaA, PFGE and MLST. RESULTS: Campylobacter jejuni was isolated from all five patients. Two of the five strains were available for typing. The DNA patterns of the two isolates were indistinguishable. CONCLUSION: The results suggest that the causal strain had a common identity.


Assuntos
Infecções por Campylobacter/epidemiologia , Surtos de Doenças , Gastroenterite/epidemiologia , Técnicas de Tipagem Bacteriana , Infecções por Campylobacter/microbiologia , Campylobacter jejuni/genética , Campylobacter jejuni/isolamento & purificação , Pré-Escolar , DNA Bacteriano/análise , DNA Bacteriano/genética , Eletroforese em Gel de Campo Pulsado , Feminino , Gastroenterite/microbiologia , Humanos , Masculino , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Espanha/epidemiologia
17.
Enferm. infecc. microbiol. clín. (Ed. impr.) ; 24(7): 437-439, ago. 2006. tab, graf
Artigo em Es | IBECS | ID: ibc-048533

RESUMO

Introducción. El objetivo de este trabajo es describir el estudio de un brote de diarrea por Campylobacter jejuni en una escuela infantil. Métodos. Se obtuvieron coprocultivos en 5 pacientes. La tipificación molecular se realizó mediante (RFLP-PCR flaA), electroforesis en campo pulsante (PFGE) y secuenciación de genes metabólicos (MLST). Resultados. Se aisló Campylobacter jejuni en los 5 enfermos. Sólo pudieron recuperarse para la tipificación 2 cepas. La tipificación mediante los 3 métodos resultó indistinguible en ambos aislamientos. Conclusión. Estos resultados sugieren una identidad común de la cepa causal (AU)


Introduction. The aim of this study is to describe an outbreak of diarrhea caused by Campylobacter jejuni in a primary school. Methods. Stool samples from five patients were cultured. Molecular typing of the isolated strains was performed using PCR-RFLP-flaA, PFGE and MLST. Results. Campylobacter jejuni was isolated from all five patients. Two of the five strains were available for typing. The DNA patterns of the two isolates were indistinguishable. Conclusion. The results suggest that the causal strain had a common identity (AU)


Assuntos
Masculino , Feminino , Pré-Escolar , Humanos , Gastroenterite/epidemiologia , Gastroenterite/microbiologia , Campylobacter jejuni/genética , Campylobacter jejuni/isolamento & purificação , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/microbiologia , Espanha/epidemiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estudos Retrospectivos , DNA Bacteriano/análise , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana
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