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1.
J Ethnopharmacol ; 253: 112656, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32035217

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Shegan-Mahuang Decoction (SMD), also named Yakammaoto or Shegan-Mahuang Tang, is a classic formula of traditional Chinese medicine with nine herbs, including Asarum sieboldii Miq., Aster tataricus L.f., Ephedra sinica Stapf, Belamcanda chinensis (L.) Redouté, Pinellia ternata (Thunb.) Breit., Schisandra chinensis (Turcz.) Baill., Tussilago farfara L., Zingiber officinale Roscoe, and Ziziphus jujuba Mill. SMD was originally discovered by Zhang Zhongjing in Eastern Han dynasty. It has been widely used as traditional medicine to treat flu-like symptoms in China and Japan for around twenty centuries. It was also utilized for the treatment of the early stage of acute asthma. However, the immune mechanisms underlying its therapeutic effects remain unknown. AIM OF THE STUDY: This study was set to investigate the effects of SMD on asthmatic airway hyperresponsiveness and its impacts on adaptive immunity in a mouse model of asthma. MATERIALS AND METHODS: The HPLC fingerprint profile of the water extract of SMD recorded 22 peaks, including those equivalent to guanosine, chlorogenic acid, tectoridin, 6-gingerol and wuweizisu B, as described previously (Yen et al., 2014). Airway hyperresponsiveness was assessed by measuring the airway resistance. Cellular infiltration was measured via H&E staining and immunochemistry while gene expression was analyzed using real-time RT-PCR. Treg frequency was determined through flow analysis whereas cytokine production in the supernatant was evaluated using ELISA. Finally, mTOR and NF-kB signalings were analyzed via Western blotting. RESULTS: We found that SMD largely corrected the imbalance of Th cell subsets in asthmatic mice with a significant inhibition of Th2 and Th17 cytokine production, thereby reducing asthmatic airway hyperresponsiveness. Moreover, lung function tests showed that SMD reduced airway hyperresponsiveness while immunohistochemical analyses demonstrated that SMD attenuated pulmonary infiltration of CD3+ and CD4+ T cells. Further, we observed a significant increase in the proportion of CD4+Foxp3+ Tregs in SMD-treated asthmatic mice. We also found that SMD downregulated gene expression of GATA3 and ROR-γt in murine lung tissue. In addition, both mTOR- and NF-kB-related protein expressions were reduced in the lung tissue of SMD-treated mice. SMD inhibited Th2/Th17 cytokine production by CD4+ T cells and also their mTOR activity in vitro. CONCLUSIONS: Our findings demonstrate that SMD attenuates asthmatic airway hyperresponsiveness by hindering Th2/Th17 differentiation, promoting CD4+FoxP3+ Treg generation and suppressing mTOR and NF-kB activities.

2.
World J Surg Oncol ; 18(1): 10, 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31931817

RESUMO

BACKGROUND: Colorectal peritoneal metastases (CPM) occur in up to 13% of patients with colorectal cancer, presenting either synchronously or metachronously. Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS and HIPEC) have been increasingly utilised for selected CPM patients with favourable outcomes, though its benefits may differ for synchronous (s-CPM) and metachronous CPM (m-CPM). METHODS: A retrospective analysis of CPM patients treated with CRS and HIPEC at the National Cancer Centre Singapore over 15 years was performed. In the s-CPM group, CPM was diagnosed at primary presentation with CRS and HIPEC performed at the time of or within 6 months from primary surgery. In the m-CPM group, patients developed CPM > 6 months after primary curative surgery. RESULTS: One hundred two patients with CPM were treated with CRS and HIPEC. Twenty (19.6%) patients had s-CPM and 82 (80.4%) had m-CPM. Recurrences occurred in 45% of s-CPM and in 54% of m-CPM (p = 0.619). Median overall survival was significantly prolonged in patients with m-CPM (45.2 versus 26.9 months, p = 0.025). In a subset of m-CPM patients with limited PCI in whom ICU stay was not required, a survival advantage was seen (p = 0.031). CONCLUSION: A survival advantage was seen a subset of m-CPM patients, possibly representing differences in disease biology.

3.
EMBO Mol Med ; : e10419, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31950591

RESUMO

The deoxycytidine analogue cytarabine (ara-C) remains the backbone treatment of acute myeloid leukaemia (AML) as well as other haematological and lymphoid malignancies, but must be combined with other chemotherapeutics to achieve cure. Yet, the underlying mechanism dictating synergistic efficacy of combination chemotherapy remains largely unknown. The dNTPase SAMHD1, which regulates dNTP homoeostasis antagonistically to ribonucleotide reductase (RNR), limits ara-C efficacy by hydrolysing the active triphosphate metabolite ara-CTP. Here, we report that clinically used inhibitors of RNR, such as gemcitabine and hydroxyurea, overcome the SAMHD1-mediated barrier to ara-C efficacy in primary blasts and mouse models of AML, displaying SAMHD1-dependent synergy with ara-C. We present evidence that this is mediated by dNTP pool imbalances leading to allosteric reduction of SAMHD1 ara-CTPase activity. Thus, SAMHD1 constitutes a novel biomarker for combination therapies of ara-C and RNR inhibitors with immediate consequences for clinical practice to improve treatment of AML.

4.
Inflammation ; 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31897917

RESUMO

There are very few reports on the protective effect of artesunate (ARS) in ulcerative colitis (UC). This study focused on the efficacy of ARS on intestinal barrier, inflammatory response, and potential mechanism in dextran sulfate sodium (DSS)-induced ulcerative colitis in mice. The results suggested that ARS treatment markedly alleviated DSS-induced clinical symptoms by relieving body weight loss, the disease activity index (DAI) score, and preventing colonic shortening. HE staining and scanning electron microscope analysis revealed that ARS treatment significantly protected the integrity of intestinal barrier through alleviating DSS-induced erosion of surface epithelial cells, reduction of goblet cells, and destruction of the crypt accompanied with inflammatory cells infiltration. Immunofluorescence histochemical staining and western blot assay confirmed that ARS notably inhibited the loss of Muc2 and claudin-1 in mucosal layer with a relative higher level of Bcl-2/Bax ratio and, moreover, inhibited cleaved-caspase-3 expression in colon tissue. In addition, this study reconfirmed the anti-inflammatory function of ARS evidenced by remarkably suppressing the phosphorylation of nuclear factor-κBα (IκBα) and NF-κB p65 and the expression of IL-1ß, IL-6, and TNF-α while enhancing IL-10 expression. Taken together, these data highlight that ARS has the protective effect on UC through maintaining the expression of intestinal mucosal barrier-related proteins, suppressing the apoptosis and inflammatory response. This study may facilitate to understand the action mechanism of ARS against UC.

5.
Sci Rep ; 10(1): 27, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31913297

RESUMO

It is often assumed that animals' temporal activity patterns are highly conserved throughout evolution. While most geckos are nocturnal, the species in the Cnemaspis genus are mostly diurnal (only a few are nocturnal). This raises a question about the evolution of a diel niche in the Cnemaspis genus. Cnemaspis geckos are distributed across Southeast Asia and are often sympatric with Cyrtodactylus, another widespread gecko genus in the same area. Since both genera are mainly rocky habitat specialists, we hypothesize that Cyrtodactylus may influence the temporal activity pattern of Cnemaspis when they are sympatric through competition. By analyzing habitat data, diel activity, and the existence of sympatric Cyrtodactylus species across the phylogeny of the Cnemaspis genus, we found (1) strong phylogenetic signals in the habitat use trait but not in temporal activity, suggesting that the diel niche of this genus is more labile compared with habitat niche, and (2) a significant association with the temporal activity pattern of Cnemaspis and the sympatry between the two genera, with the former tending to be diurnal when they are sympatric. Originated from a diurnal common ancestor, the release from competition with Cyrtodactylus species might open an opportunity for some Cnemaspis species to shift to nocturnal niches.

6.
Diabetes Ther ; 2020 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-31955370

RESUMO

INTRODUCTION: The aim of our study was to determine the effect of metformin administration on juvenile type 1 diabetes mellitus and atherosclerosis in apolipoprotein E null (ApoE-/-) mice and to explore the mechanism involved. METHODS: Eighteen male ApoE-/- mice were injected with streptozotocin to induce diabetes (diabetic group) and 18 mice who received no streptozotocin injection were assigned to the control (non-diabetic) group. Six mice in each group were then orally administered metformin, simvastatin, or vehicle, respectively, following which the mice were euthanized and tissue samples collected. RESULTS: Fasting plasma glucose, low-density lipoprotein-cholesterol, and triglyceride concentrations were significantly higher in the three diabetic groups than in the three non-diabetic groups. Plasma N∈-(carboxymethyl)lysine and N∈-(carboxyethyl)lysine concentrations were higher in the diabetic mice than in the non-diabetic mice, but metformin treatment reduced these concentrations more effectively than simvastatin. All three diabetic groups demonstrated obvious arterial plaques, but these were largest in the vehicle-treated diabetic group. The expression of extracellular nitric oxide synthase was highest in the simvastatin-treated non-diabetic group, and in diabetic mice it was higher in the simvastatin-treated group than in the other two groups. No significant expression of AMP-activated protein kinase (AMPK) was measured in the three diabetic groups, but a low level of AMPK expression was detected in the non-diabetic groups. CONCLUSIONS: Metformin can limit the development of atherosclerosis secondary to diabetes in young diabetic mice. A possible mechanism is the removal of methylglyoxal, thereby reducing the formation of advanced glycation endproducts, rather than by lowering the blood glucose level. FUNDING: This work was supported by the National Natural Science Foundation of China (81901106) and Jinan clinical medical science and technology innovation plan (201907002).

7.
Elife ; 92020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31944179

RESUMO

Oligodendrocytes (OLs) myelinate axons and provide electrical insulation and trophic support for neurons in the central nervous system (CNS). Platelet-derived growth factor (PDGF) is critical for steady-state number and differentiation of oligodendrocyte precursor cells (OPCs), but its downstream targets are unclear. Here, we show for the first time that Gab1, an adaptor protein of receptor tyrosine kinase, is specifically expressed in OL lineage cells and is an essential effector of PDGF signaling in OPCs in mice. Gab1 is downregulated by PDGF stimulation and upregulated during OPC differentiation. Conditional deletions of Gab1 in OLs cause CNS hypomyelination by affecting OPC differentiation. Moreover, Gab1 binds to downstream GSK3ß and regulated its activity, and thereby affects the nuclear accumulation of ß-catenin and the expression of a number of transcription factors critical to myelination. Our work uncovers a novel downstream target of PDGF signaling, which is essential to OPC differentiation and CNS myelination.

8.
Medicine (Baltimore) ; 99(1): e18136, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31895766

RESUMO

RATIONALE: Despite the fact that treatment of paraquat poisoning in pregnant women and their fetuses is challenging and raises ethical issues, it is rarely reported in the literature. We report the case of a pregnant woman who took paraquat intentionally. PATIENT CONCERNS: A 36-year-old woman at 38 weeks gestational age, in an apparent suicide attempt, drank 1 mouthful (about 20 ml) of paraquat solution. Ten hours later, her urine dithionate test showed light blue color with a plasma paraquat concentration of 0.547 µg/ml. Six hours after admission, a male infant, whose plasma paraquat concentration was 0.761 µg/ml, together with 0.673 µg/ml in the amniotic fluid measured by high-performance liquid chromatography, was delivered but the woman's lung, liver, and kidney function declined rapidly. DIAGNOSIS: INTERVENTIONS:: Because of placenta previa and multiple organ failure, emergency cesarean section, and panhysterectomy were performed for the pregnant woman. Intravenous injection of antibiotic to prevent infection and dexamethasone 30 mg once a day were administered. Mechanical ventilation was performed for the infant and meropenem and penicillin injection was administered. OUTCOMES: The infant died 33 hours after birth while the mother died on the 3rd day after ingestion. LESSONS: Paraquat can enter the fetus through the placenta and the amniotic fluid via fluid exchange. The pathological changes of fetal organs may relate to gestational age, and the prognosis was very poor in both the mother and the fetus.


Assuntos
Feto/efeitos dos fármacos , Herbicidas/envenenamento , Paraquat/envenenamento , Morte Perinatal , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Masculino , Morte Materna , Gravidez , Tentativa de Suicídio
9.
Indian Pediatr ; 57(1): 68-69, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31937704

RESUMO

This was a descriptive study of 30 children born to HBsAG positive mothers between June 2009 and December 2013. All children had anti-HBs response ≤100 IU/L after 3 doses of hepatitis B vaccine primary series. A single booster dose led to hepatitis B surface antibody titers ≥100 IU/L in (85%) of children.

10.
Biochem Biophys Res Commun ; 522(3): 757-762, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-31791578

RESUMO

Loss of E-cadherin elicits epithelial-mesenchymal transition (EMT). While both the Src family of membrane-associated non-receptor tyrosine kinases (SFKs) and Slit2 binding to Roundabout 1 (Robo1) have been shown to induce E-cadherin repression and EMT, whether these two signaling pathways are mechanistically coupled remains unknown in epithelial cells. Here we found that Slit2 and Robo1 overexpression activated Src kinases for tyrosine phosphorylation, degradation of E-cadherin and induction of EMT. Specific blockade of Slit2 binding to Robo1 inactivated Src, prevented E-cadherin phosphorylation and EMT induction. Biochemically, the cytoplasmic CC3 motif of Robo1 (CC3) bound directly to the SH2 and 3 domains of c-Src and the cytoplasmic domains of E-cadherin. Slit2 induced Robo1 association with endogenous c-Src and E-cadherin, whereas ectopic expression of CC3 dissociated this protein complex in colorectal epithelial cells. These results indicate that Slit2 not only induces Robo1 binding to Src, but also recruits Src to E-cadherin for tyrosine phosphorylation of E-cadherin, leading to E-cadherin degradation and EMT induction in colorectal epithelial cells.

11.
Microb Drug Resist ; 26(1): 81-88, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31738637

RESUMO

Multidrug resistance (MDR) is an increasing public health concern worldwide. Artesunate (ART) has been reported to be significantly effective in enhancing the effectiveness of various ß-lactam antibiotics against MDR Escherichia coli via inhibiting the efflux pump genes. Apart from ß-lactam antibiotics, there is no report regarding the potential synergistic effects of ART combining with fluoroquinolones (FQs). In this study, we investigated whether ART can enhance the antibacterial effects of FQs in vitro. The antibacterial activity of ART and antibiotics against 13 animal-derived E. coli clinical isolates was assessed for screening MDR strains. Then the synergistic activity of FQs with ART against MDR E. coli isolates was evaluated. Daunorubicin (DNR) accumulation within E. coli and messenger RNA (mRNA) expressions of acrA, acrB, tolC, and qnr genes were investigated. The results showed that ART did not show significant antimicrobial activity. However, a dramatically synergistic activity of ART combining with FQs was obsessed with (ΣFIC) = 0.12-0.33. ART increased the DNR accumulation and reduced acrAB-tolC mRNA expression, but enhanced the mRNA expression of qnrS and qnrB within MDR E. coli isolates. These findings suggest that ART can potentiate FQs activity which may be associated with drug accumulation by inhibiting the expression of acrAB-tolC.

12.
Crisis ; 41(1): 15-23, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30888227

RESUMO

Background: Physical illness is a strong correlate of suicidal behavior. However, its impact on attempted suicide in rural China is under-studied. Aims: This study was designed to assess the influence of physical illness on risk of suicide attempts and to identify distinguishing characteristics among medically serious suicide attempters with physical illnesses from those without. Method: Participants were medically serious suicide attempters identified through hospital emergency rooms (n = 659) as well as age- and gender-matched community controls (n = 659) from Shandong Province, China. Face-to-face interviews with the respondents were conducted with a semistructured protocol that included sociodemographic and psychological measures. Results: Physical illness was a significant risk factor for medically serious suicide attempts (OR = 1.739, 95% CI = 1.182-2.560). Older age was a significant risk factor, while female gender, no religion, and non-peasant occupations were significant protective factors for suicide attempts with physical illness. Limitations: Samples from only one province may not completely represent all serious suicide attempters in China. Furthermore, we did not assess the severity and the degree to which their physical illness limited the functioning of the individual. Conclusion: Physical illness is an important risk factor for suicide attempts in rural China. More efforts are needed to specifically target older people, males, those with religious beliefs, and peasant workers with physical illness.

13.
Emerg Infect Dis ; 26(1): 179-180, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31855529

RESUMO

China has made remarkable progress in reducing schistosomiasis caused by Schistosoma japonicum over the past 7 decades but now faces a severe threat from imported schistosomiasis. Results from national surveillance during 2010-2018 indicate integrating active surveillance into current surveillance models for imported cases is urgently needed to achieve schistosomiasis elimination in China.

14.
Pediatr Infect Dis J ; 39(1): 81-84, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31725548

RESUMO

Myocarditis is commonly associated with viruses. However, we present a novel case of a teenager with pneumococcal pneumonia and bacteremia complicated by myocarditis and rhabdomyolysis, presenting with features of acute ST-elevation myocardial infarction and cardiogenic shock. Physicians should be aware that Streptococcus pneumoniae infection, like Group A Streptococcus, can mimic acute myocardial infarction in young males without cardiovascular risk factors.

15.
Biomed Pharmacother ; 121: 109604, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31733570

RESUMO

Quercetin is a kind of flavonoid compounds that comes from nature and is widely existed in the daily diet. Previous studies have found that quercetin has many effects such as anti-inflammatory, anti-oxidation and anti-cancer. Both in vivo and in vitro experiments have demonstrated that quercetin can exert anti-tumor effects by altering cell cycle progression, inhibiting cell proliferation, promoting apoptosis, inhibiting angiogenesis and metastasis progression, and affecting autophagy. This review summarizes the evidence for the pharmacological potential and inhibition of quercetin on cancers, supporting the viewpoint that quercetin should be adequately considered as a therapeutic agent against various cancers.

16.
Oncol Lett ; 18(6): 6066-6078, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31788081

RESUMO

Melanoma is one of the most malignant types of skin cancer. However, the efficacy and utility of available drug therapies for melanoma are limited. The objective of the present study was to identify potential genes associated with melanoma progression and to explore approved therapeutic drugs that target these genes. Weighted gene co-expression network analysis was used to construct a gene co-expression network, explore the associations between genes and clinical characteristics and identify potential biomarkers. Gene expression profiles of the GSE65904 dataset were obtained from the Gene Expression Omnibus database. RNA-sequencing data and clinical information associated with melanoma obtained from The Cancer Genome Atlas were used for biomarker validation. A total of 15 modules were identified through average linkage hierarchical clustering. In the two significant modules, three network hub genes associated with melanoma prognosis were identified: C-X-C motif chemokine receptor 4 (CXCR4), interleukin 7 receptor (IL7R) and phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit γ (PIK3CG). The receiver operating characteristic curve indicated that the mRNA levels of these genes exhibited excellent prognostic efficiency for primary and metastatic tumor tissues. In addition, the proximity between candidate genes associated with melanoma progression and drug targets obtained from DrugBank was calculated in the protein interaction network, and the top 15 drugs that may be suitable for treating melanoma were identified. In summary, co-expression network analysis led to the selection of CXCR4, IL7R and PIK3CG for further basic and clinical research on melanoma. Utilizing a network-based method, 15 drugs that exhibited potential for the treatment of melanoma were identified.

17.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(6): 2003-2008, 2019 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-31839074

RESUMO

AAbstractObjective:To compare and analyze the metabolic and functional changes in platelets stored at 4 ℃ and ones stored at 22 ℃ with agitation so as to provide an experimental basis for the cryopreservation technology of platelets. METHODS: Samples were collected from platelets stored at 4 ℃ in 2, 4, 6, 11, 15 and 21 days, and from ones stored at 22 ℃ with agitation during the same days, the metabolism indicators and thromboelastogram (TEM) were analysed. RESULTS: In metabolism, there were no significant changes of pH, GLU,PCO2, PCO2 and MPV levels of platelets stored at 4 ℃ for <6 days (P>0.05), However, the Plt count decreased, the PDW and LDH level incrseased (P<0.05). At the same time, only MPV had no changes of platelets stored at 22 ℃ during above-mentioned same days (P>0.05), while the pH, PCO2, GLU, Plt all decreased, and PO2, LDH, PDW incrseased (P<0.05). There were significant changes about the pH value, PO2, Plt, MPV, LDH, GLU levels between the two kinds of stored platelets during the same storing period (P<0.05). The pH value and MPV of platelets stored at 4 ℃ were obviously lower than ones stored at 22 ℃, while GLU, PO2, LDH and Plt levels showed reverse changes (P<0.05). Meanwhile, the PCO2 of platelets stored at 4 ℃ not could be detected and the Plt count reduced rapidly from d15. In function, the MA level of platelets stored at 4 ℃ was slower than that of platelets stored at 22 ℃, that is, the MA level of platelets stored at 4 ℃ were higher than that of platelets stored at 22 ℃ during the same storeing period (P<0.05). CONCLUSION: Platelets stored at 4 ℃ have much slower metabolism than ones stored at 22 ℃, and the aggregation is stronger of platelets stored at 4 ℃ than that of ones at 22 ℃ during the same conservation period.


Assuntos
Plaquetas , Preservação de Sangue , Criopreservação , Temperatura Ambiente
18.
J Cell Biochem ; 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31886577

RESUMO

As a kind of noncoding RNAs, microRNAs (miRNAs) play important roles in disease pathogenesis by regulating gene expression. However, the molecular mechanism of miRNAs in osteoporosis remains largely unknown. In the present study, we aim to explore the genome-wide miRNAs expression profile and the regulatory mechanism of miR-205-5p in osteoporosis. A total of 72 differentially expressed miRNAs were identified in osteoporosis via microarray technology and bioinformatics analysis. We focused on one of the abnormally expressed miRNAs, miR-205-5p, which was previously unknown in osteoporosis. Quantitative real-time polymerase chain reaction (qRT-PCR) results showed that miR-205-5p was upregulated in osteoporosis samples and its expression was gradually decreased during osteogenic differentiation. Besides, miR-205-5p overexpression could inhibit the activity of osteoblast markers, including collagen, type I, α 1 (COL1A1) and alkaline phosphatase (ALP) while miR-205-5p inhibition showed the opposite results. Moreover, bioinformatics analysis identified the potential targets of miR-205-5p, including runt-related transcription factor 2 (RUNX2), SMAD1 and BCL6, etc. The dual-luciferase reporter assay confirmed RUNX2 was directly targeted by miR-205-5p. Furthermore, the rescue experiments showed that RUNX2 overexpression could significantly weaken the effect of miR-205-5p on osteoblast markers, indicating that miR-205-5p may inhibit osteogenic differentiation by targeting RUNX2.

19.
Med Sci Monit ; 25: 10029-10035, 2019 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-31879414

RESUMO

BACKGROUND This feasibility study aimed to compare real-time two-dimensional contrast-enhanced ultrasound (2D-CEUS) and three-dimensional contrast-enhanced ultrasound (3D-CEUS) to quantify flow in an in vitro model. MATERIAL AND METHODS Five polyvinyl chloride (PVC) tubes were used for the perfusion models and used SonoVue ultrasound contrast agent with a perfusion volume ratio of 1: 2: 4: 8: 16. The contrast was injected at a constant speed to compare the raw quantitative data of 2D-CEUS and 3D-CEUS at angles of 0°, 45°, and 90°. The coefficient of variation (CV) of the peak intensity (PI) in the model were compared and the correlations between weighted PI and perfusion volume were analyzed. RESULTS In the three angles used, real-time 3D-CEUS resulted in a more comprehensive view of the spatial relationships in the perfusion model. Using real-time 2D-CEUS, the mean CV was 0.92±0.36, and the mean CV in the real-time 3D-CEUS model was significantly less at 0.48±0.32 (p<0.001). Quantitative 3D-CEUS parameters showed a good correlation with those of 2D-CEUS with an r-value of 0.93 (p=0.02). The r-value of weighted PI and the perfusion ratio using 2D-CEUS was 0.66 (p=0.23) compared with values in 3D-CEUS of 0.84 (p=0.08). CONCLUSIONS The combination of real-time 3D-CEUS and quantitative analysis identified the spatial distribution of the changes in angle in the model, which was less influenced by sectional planes, and was more representative of the perfusion volume when compared with 2D-CEUS. Quantitative real-time 3D-CEUS requires in vivo studies to evaluate the potential role in the clinical evaluation of vascular perfusion of malignant tumors.

20.
Singapore Med J ; 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31680179

RESUMO

INTRODUCTION: Umbilical venous catheters (UVCs) are commonly inserted in neonates for vascular access but are not without complications. METHODS: A single-centre retrospective cohort study over 19 months reviewing complications related to UVC insertion in neonates was conducted in a tertiary neonatal unit in Singapore. Ideal UVC position was defined as catheter tip within 0.5 cm above or below the diaphragm. Catheter-related sepsis was defined as clinical or biochemical abnormalities suggesting any new-onset or worsening sepsis 72 hours before or after removal of an UVC, with or without positive culture. Catheter-associated bloodstream infection (CABSI) was defined as the positive microbiological growth in one or more blood cultures obtained from a symptomatic infant up-to two days after UVC placement or within 48 hours of catheter removal. RESULTS: Total 108 patients had UVC insertion from January 2016 - July 2017. Mean gestational age and birth weight were 30.4 ± 4.0 weeks and 1,536.2 ± 788.9 g respectively. Mean UVC duration was 6.6 days. UVC were in ideal position in 27 (25.0%), deep in 13 (12.0%) and short in 35 (32.4%) neonates. One third of the UVC (n=33) were malpositioned. Catheter related sepsis was observed in 16 (14.8%) neonates, with 5 (4.6%) having CABSI and the commonest organism being coagulase-negative Staphylococcus. Other complications were peritoneal extravasation in 3 (2.8%) patients, with two requiring surgical intervention. Venous thrombosis occurred in 2 (1.9%) neonates and was managed conservatively. CONCLUSION: Although complication rates were in line with international norms, UVCs were associated with serious complications and should be judiciously used.

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