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1.
Int J Biol Macromol ; : 133926, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39025180

RESUMO

To enhance the physicochemical properties and extend the release duration of sodium alginate (SA) hydrogels, this study explored the impact of acidifier type and the number of cross-linking on the physicochemical characteristics and in vitro anthocyanin release from SA hydrogels, utilizing calcium carbonate as the cross-linking agent. The findings revealed that the utilization of gluconolactone (GDL) as an acidifying agent in the preparation of SA hydrogels, as opposed to hydrochloric acid, resulted in a deceleration of the hydrolysis process of calcium carbonate. This deceleration led to the strengthening of hydrogen-bonding interactions and the development of a more compact network structure within the SA hydrogels. Consequently, there was a noticeable enhancement in the hardness, relaxation time, and anthocyanin encapsulation efficiency of the gels. Additionally, the release of anthocyanins in simulated intestinal fluid was delayed. Secondary cross-linking was found to facilitate ionic interactions between SA and Ca2+, further intensifying the denseness of the network structure and enhancing the physicochemical characteristics of the SA hydrogels. Overall, SA hydrogels processed with GDL as the acidifier and subjected to secondary cross-linking exhibited improved physicochemical properties, delayed release effects, and proved to be an efficient system for the delayed release of anthocyanins.

2.
Quant Imaging Med Surg ; 13(12): 8587-8598, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38106337

RESUMO

Background: Ultrasonography of the uterine artery (UtA) in the first and second trimesters of pregnancy can assess uterine-placental blood perfusion and guide early clinical prevention. Establishing normal ranges of the UtA pulsatility index (UtA-PI) at 11-14 weeks of pregnancy is helpful for the early identification of high-risk pregnant women and improving the prognosis. This study aimed to establish a reference range of UtA-PI based on crown-rump length (CRL) for spontaneous and in vitro fertilization (IVF) singleton pregnancy during 11-14 weeks, respectively. Methods: A prospective study was performed at Peking Union Medical College Hospital. Healthy, low-risk women with a singleton pregnancy at 11-14 gestational weeks were consecutively recruited for this study from December 2017 to December 2020. All participants underwent routine prenatal ultrasound examination. The CRL of the fetus and the UtA-PI were measured in both uterine arteries, and average values were calculated. The LMS method was used to fit the percentile (P)5, P10, P25, P50, P75, P90, and P95 curves of the UtA-PI value of spontaneous and IVF singleton pregnancy with CRL changes, respectively. Results: A total of 1,962 pregnant women with normal fetuses were included in this study, including 1,792 pregnancies conceived naturally and 170 IVF fetuses. The UtA-PI reference range in the spontaneous pregnancy group was consistently higher than that in the IVF group during 11-14 weeks, and showed a statistically significant difference in UtA-PI for spontaneous and IVF pregnancies (P<0.001). According to the LMS method, each percentile curve of UtA-PI decreased with the increase of CRL in both the natural pregnancy group and the IVF group. The P95 range of UtA-PI for pregnant women with naturally conceived and IVF pregnancy was 2.74 to 2.11 and 2.50 to 1.94, respectively. The overall change of UtA-PI differentials of the two groups showed a downward trend and decreased slightly with the increase of CRL. Conclusions: This study provided a single-center, large sample of data and constructed a CRL-based reference value of UtA-PI for spontaneous and IVF singleton pregnancy, which provides a reliable basis for early UtA evaluation and early clinical decision-making during 11-14 gestational weeks.

3.
Medicine (Baltimore) ; 97(38): e12437, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30235725

RESUMO

Fetal adducted thumbs have been described in association with hydrocephalus and other abnormalities, but in cases without other structural malformations the determination of prognosis and recurrence risk is challenging. The aim of our study is to analyze the characteristics, natural history, and postnatal outcome of such cases.A retrospective study was conducted over a period of 4 years in a tertiary referral center. All fetuses diagnosed as adducted thumbs without other structural malformations comprised the study group. Prenatal sonographic features and neonatal outcome are documented.There were 4 cases of fetal adducted thumbs diagnosed during the study period. No cases demonstrated other structural malformations throughout the gestation. A smaller head was noted in 2 cases during the follow-up, and all cases presented with polyhydramnios on the first or ensuing scans. Three cases died after birth due to swallowing or breathing difficulty, and the surviving 1 showed convulsion and mental retardation.Fetal adducted thumb might be an early and specific sonographic marker of impaired neurodevelopment. Close follow-up and genetic investigation should be performed in these cases. Ultrasound examination plays an important role in the prenatal diagnosis and counseling of cases without detailed prenatal genetic analysis.


Assuntos
Feto/diagnóstico por imagem , Doenças Genéticas Ligadas ao Cromossomo X/diagnóstico por imagem , Deformidades da Mão/diagnóstico por imagem , Deficiência Intelectual/diagnóstico por imagem , Transtornos do Neurodesenvolvimento/diagnóstico por imagem , Diagnóstico Pré-Natal/instrumentação , Paraplegia Espástica Hereditária/diagnóstico por imagem , Polegar/anormalidades , Polegar/diagnóstico por imagem , Ultrassonografia Pré-Natal/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Variações do Número de Cópias de DNA/genética , Feminino , Feto/anormalidades , Doenças Genéticas Ligadas ao Cromossomo X/genética , Doenças Genéticas Ligadas ao Cromossomo X/mortalidade , Idade Gestacional , Humanos , Deficiência Intelectual/genética , Deficiência Intelectual/mortalidade , Imageamento por Ressonância Magnética/métodos , Masculino , Poli-Hidrâmnios/diagnóstico por imagem , Gravidez , Estudos Retrospectivos , Paraplegia Espástica Hereditária/genética , Paraplegia Espástica Hereditária/mortalidade , Polegar/patologia
4.
J Ultrasound Med ; 31(5): 747-55, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22535722

RESUMO

OBJECTIVES: The purpose of this study was to investigate the influence of atherosclerosis and age on 4 representative Doppler parameters in the diagnosis of renal artery stenosis. METHODS: The 4 parameters, renal peak systolic velocity (PSV), renal-aortic ratio, renal-interlobar ratio, and acceleration time, were measured in 208 patients before angiography. The 208 patients were divided into groups according to age and atherosclerosis stratification. The Student t test, 1-way analysis of variance, and the χ(2) test were used to compare all 4 parameters and clinical characteristics. The optimal cutoff values were determined by receiver operating characteristic curves. The diagnostic concordance between atherosclerosis and age strata was evaluated by the Cohen κ coefficient. RESULTS: Of the 416 renal arteries shown on Doppler sonography, 204 had a diagnosis of renal artery stenosis and 19 as occlusion on angiography. The optimal cutoff values for the renal-aortic ratio and renal-interlobar ratio in the groups aged 46 years or older and younger than 46 years were much different (2.3 versus 1.4 and 5.1 versus 6.5, respectively), whereas those for the renal PSV and acceleration time were close to each other or the same (170 versus 180 cm/s and 51 versus 51 milliseconds). The κ coefficients for the renal PSV, renal-interlobar ratio, acceleration time, and renal-aortic ratio between the atherosclerosis and age strata were 0.93, 0.99, 1.00, and 0.71. CONCLUSIONS: Atherosclerosis and age show comparable influences on Doppler parameters in the diagnosis of renal artery stenosis. For clinical convenience, cutoff values may be separately established on the basis of a 46-year-old borderline for the renal-aortic ratio and renal-interlobar ratio, although this process is not necessary for the renal PSV and acceleration time.


Assuntos
Aterosclerose/complicações , Aterosclerose/diagnóstico por imagem , Obstrução da Artéria Renal/diagnóstico por imagem , Obstrução da Artéria Renal/etiologia , Ultrassonografia Doppler , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia , Área Sob a Curva , Distribuição de Qui-Quadrado , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC
6.
Chin Med Sci J ; 25(3): 151-5, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21180276

RESUMO

OBJECTIVE: To analyze the clinical and ultrasonographic imaging features of intraductal papillary mucinous neoplasm (IPMN) of the pancreas. METHODS: Twelve patients with IPMN underwent surgery between May 2005 and December 2008, including 4 (33.3%) with adenoma and 8 (66.7%) with adenocarcinoma. IPMN was classified preoperatively into 3 types based on sonographic findings of different sites: main duct, branch duct, and combined type. All clinical presentations and ultrasonographic findings of those patients were reviewed and the correlation between ultrasonographic findings and histopathological results was analyzed. RESULTS: There were 9 men and 3 women with a mean age of 60.1 +/- 9.6 years (range, 32-73). Of all the 12 patients with IPMN, 9 (75.0%) had experienced some symptoms of epigastric discomfort and/or pain as well as backache; 7 cases were with medical history of acute pancreatitis, 5 cases with diabetes, 4 cases with elevated CA19-9, and 2 cases with steatorrhea. All lesions of IPMN have been revealed by transabdominal ultrasonography. The mean diameters of the lesions were 1.4 +/- 0.8 cm (range, 0.5-2.0) and 6.3 +/- 6.0 cm (range, 2.0-20.0) in adenomas and adenocarcinomas, respectively. And the mean diameters of the main duct in adenomas and adenocarcinomas were 1.0 +/- 0.8 cm and 1.6 +/- 1.0 cm, respectively. Among the 4 adnomas, 3 (75.0%) cases were classified as branch type based on sonographic findings, and 2 were demonstrated as mural nodules in which no color signals was detected. Among the 8 adenocarcinomas, 5 (62.5%) cases were classified as main duct type, and 3 (37.5%) as combined type. In 7 of the 8 adenocarcinomas, mural nodules were detected within the dilated ducts or cysts of the lesions in which color flow signals were detected. CONCLUSIONS: Transabdominal ultrasonography can reveal the pancreatic cystic lesions of IPMN as well as dilated pancreatic ducts. Some characteristics should be noticed as suggesting the possibility of malignancy: clinical symptoms of pancreatic insufficiency, large tumor size, and mural nodules with color Doppler flow signals. Transabdominal ultrasonography could be a useful tool to help diagnose and make appropriate management of IPMN.


Assuntos
Adenocarcinoma Mucinoso/diagnóstico por imagem , Carcinoma Ductal Pancreático/diagnóstico por imagem , Carcinoma Papilar/diagnóstico por imagem , Neoplasias Pancreáticas/diagnóstico por imagem , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cisto Pancreático/diagnóstico por imagem , Ultrassonografia
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