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1.
Radiology ; 304(3): 527-528, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35503016

RESUMO

Online supplemental material is available for this article.


Assuntos
Canal Anal , Imageamento Tridimensional , Canal Anal/diagnóstico por imagem , Humanos , Imageamento Tridimensional/métodos , Ultrassonografia/métodos
2.
BMC Pregnancy Childbirth ; 20(1): 221, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32295539

RESUMO

BACKGROUND: Since conjoined twins were thought to be monoamniotic in the past, diamniotic conjoined twins would be improbable theoretically. Body stalk anomaly is a severe defect of the body wall, which is rare among twins. Body stalk anomaly in monochorionic diamniotic conjoined twins has never been reported prenatally so far as we know. CASE PRESENTATION: Here we present an extremely rare case of concordant body stalk anomaly in monochorionic diamniotic conjoined twins. Ultrasonography at 9 + 5 weeks revealed one chorionic and two amniotic cavities, close apposition of abdomen, limited movement, and common umbilical vessels. Follow-up ultrasonography at 11 + 6 weeks and 13 + 2 weeks showed close apposition of the lower abdominal region with cystic structures and a small bowel-like mass between the two fetuses. Three-dimensional ultrasonography assisted in observing the entire appearance of both twins in earlier first trimester, including amnioticity, conjoined region and umbilical vessels. We attribute this diamniotic conjoined twin in our case to the fusion theory. A single yolk sac was observed, challenging the idea that yolk sac number predicts amnionicity. Identification of single yolk sac and its allantois may form a common body stalk during this fusion, leading to concordant body stalk anomaly in monochorionic diamniotic twins. CONCLUSIONS: Our case may provide important insights into both ultrasonographic features and embryogenesis of this extremely rare anomaly.


Assuntos
Membranas Extraembrionárias/diagnóstico por imagem , Feto/anormalidades , Feto/diagnóstico por imagem , Gêmeos Unidos/embriologia , Adulto , Feminino , Humanos , Imageamento Tridimensional , Gravidez , Primeiro Trimestre da Gravidez , Ultrassonografia Pré-Natal
3.
Chemistry ; 25(52): 12098-12104, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31278781

RESUMO

An amazing phenomenon of the relative magnitude of modulus of two liquid-crystal (LC) gels is found inverted under/above their phase transition temperature TLC-iso , which is further proved to be caused by their diverse morphology flexibility. By testing the polarity of two LCs, gelator POSS-G1-Boc (POSS=polyhedral oligomeric silsesquioxane) was discovered to self-assemble into more flexible structures in a relatively low polar LC, whereas more rigid ones are formed in higher polar LC. Hence, a fitting function to connect morphology flexibility with solvent polarity was established, which can even be generalized to a number of common solvents. Experimental observations and coarse-grained molecular dynamics simulations revealed that solvent polarity mirrors a "Morse code", with each "code" corresponding to a specific morphology flexibility.

4.
Langmuir ; 35(7): 2649-2654, 2019 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-30672709

RESUMO

A novel fluorescence chemosensor that can quickly on-site detect synthetic drugs and undergo prescreening is first reported. An eight tetraphenylethene (TPE)-modified polyhedral oligomeric silsesquioxane (POSS) dendrimer is designed and synthesized as an aggregation-induced emission (AIE) chemosensor, which exhibits great enhancement of unique monomer emission in pure tetrahydrofuran (THF) and AIE emission in THF/water, thanks to forming different self-assembly morphologies. In addition, POSS-TPE can sensitively detect methamphetamine and ketamine even in artificial saliva by noncovalent interaction forces. It has great potential to be a new widely applicable AIE chemosensor for aromatic molecules.


Assuntos
Dendrímeros/química , Ketamina/análise , Metanfetamina/análise , Compostos de Organossilício/química , Estilbenos/química , Dendrímeros/síntese química , Dendrímeros/efeitos da radiação , Compostos de Organossilício/síntese química , Compostos de Organossilício/efeitos da radiação , Saliva/química , Espectrometria de Fluorescência/métodos , Estilbenos/síntese química , Estilbenos/efeitos da radiação , Raios Ultravioleta
5.
Curr Med Imaging Rev ; 14(1): 139-142, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29399013

RESUMO

OBJECTIVE: The present study is planned to discuss the clinical value of prenatal 3D ultra-sonic diagnosis on fetus hemivertebra deformity through the retrospective analysis of clinical data of fetus hemivertebra deformity. METHODS: Selected 9 fetus hemivertebra deformity cases, which have been admitted to our hospital during the period from January, 2010 to January, 2016 as study samples, and analyzed their 2D and 3D ultrasonic examination data. RESULTS: 4 cases of the fetus hemivertebra deformity occurred at lumbar vertebra, 3 cases at thoracic vertebra, and 2 cases at thoracolumbar vertebra. There were scoliosis and opened spine bifida (OSB). In 7 cases, there was absence of ribs in fetus. The 2D ultrasonic image showed that: The echo at the center of fetus vertebral arch lesion was blurred or lost. The coronal section showed the deformity of the spine. There was obvious loss of the ossification center. From the cross section, we could see that the vertebral body of the fetus was shrinking and the edges were relatively blurred. The 3D ultrasonic image showed that: the echo at the ossification center of the fetus vertebra was relatively blurred, or even lost. The image also indicated scoliosis deformity of the spine. The vertebral body lesion could be accurately located. CONCLUSION: 9 cases of fetus hemivertebra deformity have been detected through examination. Labor inductions have been carried out after getting the permission from the family members. The X-ray examination of the fetus after labor induction showed that the diagnosis was correct. Prenatal ultra-sonic examination holds strong potential for the diagnosis of fetus hemivertebra deformity quite early and deserves further clinical evaluation with large sample size.

6.
Langmuir ; 33(50): 14389-14395, 2017 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-29172526

RESUMO

The benzene ring of low-molecular-weight gelators provides strong intermolecular forces but increases molecular spacing during self-assembly. To explore both of the above influences on the gel properties, we synthesize two gelators (Glu-CBZ and Glu-DPA) consisting of the same terminal long side chain but different aliphatic functional groups. The aliphatic functional groups are carbobenzoxy group and diphenyl phosphate group. The self-assembly driving forces, self-organization patterns, network morphologies, rheological properties, and the influences of solvents are researched through 1H NMR spectra, Fourier transform infrared spectra, field-emission scanning electron microscopy images, rheological characterizations curves, tube-inversion experiment, and calculation of van't Hoff plots. The results show that the carbobenzoxy group of Glu-CBZ makes molecules pack more tightly such that it improves the gel properties during static equilibrium. Whereas the diphenyl phosphate group of Glu-DPA provides stronger intermolecular forces, performing outstandingly during dynamic equilibrium. It is advantageous to further investigate the competitive relationship in gel system between the increased number of functional groups and the consequent steric effect.

7.
Langmuir ; 33(46): 13332-13342, 2017 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-29072455

RESUMO

Aromatic groups are introduced into the end peripherals of polyhedral oligomeric silsesquioxane (POSS) core-based organic/inorganic hybrid supramolecules to get a novel dendrimer gelator POSS-Z-Asp(OBzl) (POSS-ASP), which have eight aspartate derivative arms to make full use of strong π-π stacking forces to get strong supramolecular gels in addition to multiple hydrogen bindings and van der Waals interactions. POSS-ASP can self-assemble into three-dimensional nanoscale gel networks to provide hybrid physical gels especially with strong mechanical properties and fast-recovery behaviors. Two totally different morphologies of the connected spherical particle structures and banded ultralong fibers are observed owing to the polarity of solvents confirmed by the scanning electron microscopy, polarized optical microscopy, and transmission electron microscopy techniques, expecting the existing various self-assembly models and illustrating the peripherals of the dendrimer and the polarity of solvents having huge influences in the supramolecular self-assembly mechanism. What is more, the thermal stability, rheological properties, and network architecture information have also been investigated via tube-inversion, rotational rheometer, and powder X-ray diffraction methods, the results of which confirm the two different gel formation mechanisms that make POSS-ASP to exhibit two totally different thermal and mechanical properties. Such a study reports a new gelation system in organic or organic/aqueous mixed solvents, which can be helpful for investigating the relationship of dendritic supramolecular gelation and different polarity solvents during the supramolecular self-assembly process of gelators.

8.
ACS Appl Mater Interfaces ; 9(13): 11924-11932, 2017 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-28272864

RESUMO

A kind of body temperature controlled optical and thermal information storage light scattering display based on super strong liquid crystalline physical gel with special "loofah-like gel network" was successfully prepared. Such liquid crystal (LC) gel was obtained by mixing a dendritic gelator (POSS-G1-BOC), an azobenzene compound (2Azo2), and a phosphor tethered liquid crystalline host (5CB), which could show its best contrast ratio at around human body temperature under UV light because of the phosphor's fluorescence effect. The gel also has quite strong mechanical strength, which could be used in wearable device field especially under sunlight, even under the forcing conditions as harsh as being centrifuged for 10 min at the speed of 2000 r/min. The whole production process of such a display is quite simple and could lead to displays at any size through noncontact writing. We believe it will have wide applications in the future.

9.
Soft Matter ; 12(3): 957-64, 2016 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-26568047

RESUMO

Super strong and fast-recovery organic/inorganic hybrid gold nanoparticle (AuNPs)-supramolecular gels based on a three-dimensional loofah-like nanoscale network self-assembled by polyhedral oligomeric silsesquioxane (POSS) core supramolecular gelators are reported for the first time. Two series of POSS core organic/inorganic hybrid gelators, POSS-BOC-l-Homophenylalanine (POSS-Hpy) and POSS-Boc-Cys(Bzl)-OH (POSS-Cys), with two types of peripherals having different abilities for driving the self-assembly of AuNPs in gels were designed and synthesized, both of which self-assembled into three-dimensional loofah-like nanoscale gel networks producing hybrid physical gels with fast-recovery behaviors. The mechanical properties of the resultant hybrid gels were dramatically increased by as much as 100 times in the system of sulfur containing POSS-Cys gelators without destroying the fast-recovery behaviors, with the addition of AuNPs, which had direct interaction with AuNPs to give S-Au non-covalent driving force to lead AuNPs self-assemble onto the 3D loofah-like network nanofibres in the supramolecular hybrid gel system. However, in the POSS-Hpy gelator system without sulfur, no strong interaction with AuNPs existed and the POSS-Hpy nanocomposites showed no clear changes in morphology, thermal stability or rheological properties, confirmed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), tube-inversion and rotational rheometer measurements. This indicated that the organic/inorganic hybrid gelator POSS-Cys could be applied to the formation of soft materials in which AuNPs were self-assembled and closely arranged into three-dimensional nanoscale networks. This hybrid material has great potential for applications in self-recovery, nano- and micron-scale electronic devices, because it has both a large mechanical strength and a fast-recovery capability.

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