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1.
BMC Med Imaging ; 24(1): 141, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38862884

RESUMO

OBJECTIVE: To evaluate the consistency between doctors and artificial intelligence (AI) software in analysing and diagnosing pulmonary nodules, and assess whether the characteristics of pulmonary nodules derived from the two methods are consistent for the interpretation of carcinomatous nodules. MATERIALS AND METHODS: This retrospective study analysed participants aged 40-74 in the local area from 2011 to 2013. Pulmonary nodules were examined radiologically using a low-dose chest CT scan, evaluated by an expert panel of doctors in radiology, oncology, and thoracic departments, as well as a computer-aided diagnostic(CAD) system based on the three-dimensional(3D) convolutional neural network (CNN) with DenseNet architecture(InferRead CT Lung, IRCL). Consistency tests were employed to assess the uniformity of the radiological characteristics of the pulmonary nodules. The receiver operating characteristic (ROC) curve was used to evaluate the diagnostic accuracy. Logistic regression analysis is utilized to determine whether the two methods yield the same predictive factors for cancerous nodules. RESULTS: A total of 570 subjects were included in this retrospective study. The AI software demonstrated high consistency with the panel's evaluation in determining the position and diameter of the pulmonary nodules (kappa = 0.883, concordance correlation coefficient (CCC) = 0.809, p = 0.000). The comparison of the solid nodules' attenuation characteristics also showed acceptable consistency (kappa = 0.503). In patients diagnosed with lung cancer, the area under the curve (AUC) for the panel and AI were 0.873 (95%CI: 0.829-0.909) and 0.921 (95%CI: 0.884-0.949), respectively. However, there was no significant difference (p = 0.0950). The maximum diameter, solid nodules, subsolid nodules were the crucial factors for interpreting carcinomatous nodules in the analysis of expert panel and IRCL pulmonary nodule characteristics. CONCLUSION: AI software can assist doctors in diagnosing nodules and is consistent with doctors' evaluations and diagnosis of pulmonary nodules.


Assuntos
Inteligência Artificial , Diagnóstico por Computador , Neoplasias Pulmonares , Tomografia Computadorizada por Raios X , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Estudos Retrospectivos , Pessoa de Meia-Idade , Masculino , Idoso , Feminino , Adulto , Diagnóstico por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Detecção Precoce de Câncer/métodos , Curva ROC , Redes Neurais de Computação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Software
2.
Int J Clin Pract ; 2023: 5562495, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37609664

RESUMO

Background: Tuberculosis (TB), a multisystemic disease with protean presentation, remains a major global health problem. Although concurrent pulmonary tuberculosis (PTB) and extrapulmonary tuberculosis (EPTB) cases are commonly observed clinically, knowledge regarding concurrent PTB-EPTB is limited. Here, a large-scale multicenter observational study conducted in China aimed to study the epidemiology of concurrent PTB-EPTB cases by diagnostically defining TB types and then implementing association rules analysis. Methods: The retrospective study was conducted at 21 hospitals in 15 provinces in China and included all inpatients with confirmed TB diagnoses admitted from Jan 2011 to Dec 2017. Association rules analysis was conducted for cases with concurrent PTB and various types of EPTB using the Apriori algorithm. Results: Evaluation of 438,979TB inpatients indicated PTB was the most commonly diagnosed (82.05%) followed by tuberculous pleurisy (23.62%). Concurrent PTB-EPTB was found in 129,422 cases (29.48%) of which tuberculous pleurisy was the most common concurrent EPTB type observed. The multivariable logistic regression models demonstrated that odds ratios of concurrent PTB-EPTB cases varied by gender and age group. For PTB cases with concurrent EPTB, the strongest association was found between PTB and concurrent bronchial tuberculosis (lift = 1.09). For EPTB cases with concurrent PTB, the strongest association was found between pharyngeal/laryngeal tuberculosis and concurrent PTB (lift = 1.11). Confidence and lift values of concurrent PTB-EPTB cases varied with gender and age. Conclusions: Numerous concurrent PTB-EPTB case types were observed, with confidence and lift values varying with gender and age. Clinicians should screen for concurrent PTB-EPTB in order to improve treatment outcomes.


Assuntos
Tuberculose Extrapulmonar , Tuberculose Pleural , Tuberculose Pulmonar , Humanos , Tuberculose Pleural/complicações , Tuberculose Pleural/epidemiologia , Estudos Retrospectivos , Tuberculose Pulmonar/complicações , Tuberculose Pulmonar/epidemiologia , China/epidemiologia
3.
BMC Anesthesiol ; 23(1): 102, 2023 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-37003967

RESUMO

BACKGROUND: To investigate the risk factors for delayed neurocognitive recovery in elderly patients undergoing thoracic surgery. METHODS: A total of 215 elderly patients who underwent thoracic surgery between May 2022 and October 2022 were recruited in this prospective observational study. Cognitive function was tested by MoCA tests that were performed by the same trained physician before surgery, on postoperative day 4 (POD4), and on postoperative day 30 (POD30). Univariate and multivariate logistic regression models were used to analyze the risk factors for DNR. RESULTS: A total of 154 patients (55.8% men) with an average age of 67.99 ± 3.88 years were finally included. Patients had an average preoperative MoCA score of 24.68 ± 2.75. On the 30th day after surgery, 26 (16.88%) patients had delayed postoperative cognitive recovery, and 128 (83.12%) had postoperative cognitive function recovery. Diabetes mellitus (OR = 6.508 [2.049-20.664], P = 0.001), perioperative inadvertent hypothermia (< 35℃) (OR = 5.688 [1.693-19.109], P = 0.005), history of cerebrovascular events (OR = 10.211 [2.842-36.688], P < 0.001), and VICA (sevoflurane combined with propofol anesthesia) (OR = 5.306 [1.272-22.138], P = 0.022) resulted as independent risk factors of delayed neurocognitive recovery. On the POD4, DNR was found in 61 cases (39.6%), and age ≥ 70 years (OR = 2.311 [1.096-4.876], P = 0.028) and preoperative NLR ≥ 2.5 (OR = 0.428 [0.188-0.975], P = 0.043) were identified as independent risk factors. CONCLUSIONS: The risk factors for delayed neurocognitive recovery in elderly patients undergoing thoracic surgery include diabetes, perioperative inadvertent hypothermia (< 35℃), VICA (sevoflurane combined with propofol anesthesia), and history of cerebrovascular events.


Assuntos
Hipotermia , Propofol , Cirurgia Torácica , Masculino , Humanos , Idoso , Pessoa de Meia-Idade , Feminino , Propofol/efeitos adversos , Sevoflurano/efeitos adversos , Hipotermia/induzido quimicamente , Complicações Pós-Operatórias/psicologia , Fatores de Risco
4.
Eur J Clin Microbiol Infect Dis ; 40(4): 787-800, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33094354

RESUMO

In clinical practice, PTB patients have concurrent many types of comorbidities such as pneumonia, liver disorder, diabetes mellitus, hematological disorder, and malnutrition. Detecting and treating specific comorbidities and preventing their development are important for PTB patients. However, the prevalence of most comorbid conditions in patients with PTB is not well described. We conducted a large-scale, multicenter, observational study to elucidate and illustrate the prevalence rates of major comorbidities in inpatients at 21 hospitals in China. The 19 specific comorbidities were selected for analysis in this patient cohort, and stratified the inpatient cohort according to age and gender. A total of 355,929 PTB inpatients were included, with a male:female ratio of 1.98 and the proportion of ≥ 65 years PTB inpatients was the most. Approximately 70% of PTB inpatients had at least one defined type of comorbidity. The prevalence of 19 specific comorbidities in inpatients with PTB was analyzed, with pneumonia being the most common comorbidity. The prevalence of most comorbidities was higher in males with PTB except thyroid disorders, mental health disorders, etc. The prevalence of defined most comorbidities in patients with PTB tended to increase with increasing age, although some specific comorbidities tended to increase initially then decrease with increasing age. Our study describes multiple clinically important comorbidities among PTB inpatients, and their prevalence between different gender and age groups. The results will enhance the clinical aptitude of physicians who treat patients with PTB to recognize, diagnose, and treat PTB comorbidities early.


Assuntos
Comorbidade , Pacientes Internados , Tuberculose Pulmonar/complicações , Tuberculose Pulmonar/epidemiologia , Adolescente , Adulto , Idoso , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
5.
Macromol Rapid Commun ; 42(11): e2100033, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33904224

RESUMO

In order to prepare materials with controllable properties, changeable microstructure, and high viscoelasticity solution with low polymer and surfactant concentration, a composite is constituted by adding surfactant (sodium dodecyl sulfate, SDS) to hydrophobically associated water-soluble polymer (abbreviated as PAAC) solution. The viscoelasticity, aggregate microstructure, and interaction mechanism of the composite are investigated by rheometery, Cryo-transmission electron microscopy (Cryo-TEM), and fluorescence spectrum. The results show that when the mass ratio of polymer to surfactant is 15:1, the viscosity of the composite reaches the maximum. The viscosity of the composite system increases hundredfold. The viscosity plateau under dynamic shear is generated. The composite has the properties of high viscoelasticity, strong shear thinning behavior, and good salt tolerance, and temperature resistance. The maximum viscosity of the composite is shown at the salinity of 20000 mg L-1 . In addition, there is no phase separation in the composite with the increase of polymer and surfactant concentration, which indicates the good stability of the system. It is proposed a method to obtain a high viscoelasticity solution by adding surfactants without wormlike micelles to a hydrophobically associated water-soluble polymer solution.


Assuntos
Polímeros , Tensoativos , Micelas , Viscosidade , Água
6.
Trop Med Int Health ; 25(3): 373-379, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31802572

RESUMO

OBJECTIVE: Tuberculosis (TB) treatment success rates are high in China, but there are still a considerable number of cases who have unfavourable treatment outcomes (UTO). We aimed to determine the proportion of TB patients with UTO and to assess whether baseline characteristics that included glycaemic status [normal fasting blood glucose (FBG), transient hyperglycaemia and diabetes mellitus (DM)] and vitamin D status were associated with UTO. METHOD: Prospective cohort study conducted between November 2015 and July 2016 at six clinics within routine TB services in Jilin province, where persons with TB were consecutively recruited. Data analysis was performed using the chi-squared test and multivariate logistic regression. RESULTS: Of the 306 recruited TB patients, 96 (31.4%) had smear-positive pulmonary TB, 187 (61.1%) had smear-negative pulmonary TB and 23 (7.5%) had extrapulmonary TB (EPTB). Of these, 95 (31.1%) had normal blood glucose, 83 (27.1%) had transient hyperglycaemia and 128 (41.8%) had DM. 227 (74.2%) patients had vitamin D deficiency/severe deficiency. There were 125 (40.8%) patients with UTO of whom the majority were lost to follow-up (57.6%) or not evaluated (28.8%). UTO was significantly associated with smear-negative pulmonary TB (P = 0.009), EPTB (P < 0.001) and DM (P = 0.007). CONCLUSION: The proportion of TB patients with UTO increased with smear-negative pulmonary TB, EPTB and DM. TB programmes need to pay more attention to these issues and ensure intensive patient support to those at risk and early detection of DM.


OBJECTIF: Les taux de succès du traitement de la tuberculose (TB) sont élevés en Chine, mais il existe encore un nombre considérable de cas avec des résultats de traitement défavorables (RTD). Nous avons cherché à déterminer la proportion de patients TB avec un RTD et d'évaluer si les caractéristiques de base comprenant le statut glycémique [glycémie normale à jeun (GJ), hyperglycémie transitoire et diabète sucré (DS)] et le statut en vitamine D étaient associés à un RTD. MÉTHODE: Etude de cohorte prospective réalisée entre novembre 2015 et juillet 2016 dans six cliniques des services anti-TB de routine de la province de Jilin, où des personnes atteintes de TB ont été recrutées consécutivement. L'analyse des données a été réalisée à l'aide du test du chi carré et de la régression logistique multivariée. RÉSULTATS: Sur 306 patients TB recrutés, 96 (31.4%) avaient une TB pulmonaire à frottis positif, 187 (61.1%) avaient une TB pulmonaire à frottis négatif et 23 (7.5%) avaient une TB extra pulmonaire (TBEP). Parmi ceux-ci, 95 (31.1%) avaient une glycémie normale, 83 (27.1%) avaient une hyperglycémie transitoire et 128 (41.8%) avaient un DS. 227 (74.2%) patients avaient une déficience/déficience sévère en vitamine D. Il y avait 125 (40.8%) patients avec un RTD dont la majorité (57.6%) ont été perdus de vue ou ont été non évalués (28.8%). Le RTD était significativement associé à la TB pulmonaire à frottis négatif (p = 0.009), la TBEP (P < 0.001) et le DS (P = 0.007). CONCLUSION: La proportion de patients TB avec un RTD augmentait avec la TB pulmonaire à frottis négatif, la TBEP et le DS. Les programmes anti-TB devraient accorder plus d'attention à ces problèmes et assurer un soutien intensif au patient pour les personnes à risque et une détection précoce du DS.


Assuntos
Glicemia/metabolismo , Tuberculose Pulmonar/epidemiologia , Vitamina D/sangue , Idoso , China/epidemiologia , Estudos de Coortes , Diabetes Mellitus Tipo 2/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Tuberculose Pulmonar/sangue , Tuberculose Pulmonar/complicações , Tuberculose Pulmonar/tratamento farmacológico , Deficiência de Vitamina D/complicações
7.
Soft Matter ; 16(42): 9705-9711, 2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-32996541

RESUMO

In recent years, the use of dynamic chemical bonds to construct stimulus-responsive micelle systems has received increasing attention. However, current reports focus on the construction of dynamic covalent bond surfactants using dynamic chemical bonds, and the method of applying dynamic covalent bonds to hydrotropes has not been reported yet. In this study, a novel pH-responsive worm-like micelle system was constructed by mixing cetyltrimethylammonium bromide (CTAB), 4-hydroxybenzaldehyde (HB) and p-toluidine (MB) at the molar ratio of 60 mM : 40 mM : 40 mM. The formation mechanism of the dynamic covalent bond hydrotropes and the rheological behavior of the micelles were investigated via rheology, 1H-NMR spectroscopy and Cryo-TEM. The results show that as the pH increases, the viscosity of the solution first decreases and then increases rapidly. The microscopic aggregates in the solution transition from spherical micelles to worm-like micelles (WLMs), and the solution changes from a water-like fluid without viscosity to a gel system that can withstand its own weight. The transformation of the aggregates and their rheology can be attributed to the formation of MB-HB-, which is a type of hydrotrope with dynamic covalent bonds. Moreover, the transition from spherical micelles to worm-like micelles in this system is reversible.

8.
Soft Matter ; 16(16): 4024-4031, 2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32270152

RESUMO

The gemini-like surfactants have been constructed by compounding N-erucamidopropyl-N,N-dimethylamine (UC22AMPM) and o-phthalic acid (o-PA), m-phthalic acid (m-PA), or p-phthalic acid (p-PA), and are denoted as o-EAPA, m-EAPA, and p-EAPA, respectively. It is well known that inorganic salts have significant effects on surfactant aggregates, and herein the effects of sodium chloride (NaCl) on gemini-like surfactants is explored by rheological and dynamic light scattering measurements, and cryo-TEM. It is found that the viscoelasticity of the EAPA systems first increases and then decreases with an increase of the NaCl concentration. And the optimal NaCl concentrations for these three systems are in the order of o-EAPA < m-EAPA < p-EAPA due to different spacer distances between the two carboxyl groups in the phthalic acid. Similar trends in the N,N-dimethyl oleoaminde-propylamine (DOAPA) and o-PA, m-PA, or p-PA systems were also observed. The results show that an appropriate NaCl concentration will promote gemini-like surfactants to form wormlike micelles (WLMs). Upon further increasing the NaCl concentration, the WLMs transform into vesicles. Excessive NaCl concentration will cause the surfactant systems to reach their cloud point and make the surfactants precipitate out. The mechanism of the effects of NaCl is that Cl- reduces the electrostatic repulsion between the headgroups of the surfactants. This work is helpful in understanding the effects of inorganic salts on the surfactants and this study is useful for exploring the practical applications of gemini-like surfactants.

9.
Soft Matter ; 15(15): 3160-3167, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30865762

RESUMO

A worm-like micelle (WLM) system can be obtained by mixing long-chain cationic surfactants and polybasic organic acids in an aqueous solution. However, the effect of different organic acid structures on the rheological behavior of WLM systems has not been researched. Herein, a novel pH-responsive wormlike micelle system (EATA) was constructed by the complexation of N-erucamidopropyl-N,N-dimethylamine (UC22AMPM) and benzene tricarboxylic acid (TA) at a molar ratio of 3 : 1. UC22AMPM/citric acid (EACA) was also prepared to perform a comparison. The rheological behavior, aggregate transformation and thickening mechanism of EATA solutions were investigated by using rheological measurements, cryo-TEM, DLS, surface tension and 1H NMR. The results show that, at low pH, spherical micelles were formed and the EATA solution exhibited a lower viscosity than the EACA system due to the strong hydrophobicity of the phenyl groups of TA molecules, but the viscosity reaches 106 mP s at pH 4.80. Because of the lower pKa value of TA than CA, the viscosity of the EATA system drops sharply with the appearance of precipitates caused by the isoelectric point when the pH is greater than 4.80. In addition, by circularly changing the pH value several times, the wormlike micelles could maintain their original viscoelasticity without being weakened in the slightest.

10.
Soft Matter ; 15(12): 2703-2710, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30816889

RESUMO

A dynamic covalent bond is widely used to fabricate stimuli responsive systems due to its reversible molecular recognition properties. In this study, we developed a pH-responsive morphology transition system based on a mixture of a cationic surfactant CTAB and two nonamphiphilic precursors, 4-hydroxybenzaldehyde (HB) and octylamine (OA), at a molar ratio of 100 : 60 : 60 (CTAB/HB/OA). The morphology transition of CTAB/HB/OA was characterized by 1H NMR spectroscopy, Fourier transform infrared spectroscopy, macroscopic appearance observation, dynamic light scattering, and rheological and cryo-TEM measurements. The phase behavior of CTAB/HB/OA solutions underwent transition from a water-like fluid to a transparent gel-like solution and then converted into a turbid low-viscosity solution upon increasing the pH. Upon increasing the pH from 4.93 to 7.99, the morphology was transformed from spherical micelles to wormlike micelles. Upon further increasing the pH to 12.02, the wormlike micelles gradually disappeared with the formation of vesicles. Thus, a morphology transition from micelles to vesicles can be triggered by varying the pH of CTAB/HB/OA solutions. This drastic variation in morphology behavior was attributed to the pH dependent ionization and formation of the anionic surfactant HB-OA-. Besides, over 3 cycles of morphological alternation among spherical micelles, wormlike micelles and vesicles of the CTAB/HB/OA solutions can be obtained by adjusting the pH.

11.
Soft Matter ; 14(22): 4445-4452, 2018 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-29693695

RESUMO

Responsive wormlike micelles (WLMs) constructed by different carboxylic acids are fascinating. However, it is unknown how the position of the carboxylic groups alters the stimuli-response of wormlike micellar systems. Herein, three pH-responsive WLMs based on Gemini-like surfactants (named o-EAPA, m-EAPA, and p-EAPA) were formed and studied through the complexation of N-erucamidopropyl-N,N-dimethylamine (UC22AMPM) and o-phthalic acid (o-PA), m-phthalic acid (m-PA), or p-phthalic acid (p-PA) at the molar ratio of 2 : 1. The viscoelasticity, phase behavior and aggregate microstructure were separately explored by rheological, appearance observation and cryo-TEM methods. The results show that all phthalic acids can protonate UC22AMPM, thereby forming WLMs. However, with the shorter spacer distance between two carboxyl groups in phthalic acid, o-EAPA exhibits the longer length scale of aggregates and a more efficient thickening ability compared to the other two systems. Similar results in the N,N-dimethyl oleoaminde-propylamine (DOAPA) and o-PA, m-PA, and p-PA systems further verify the applicability of this mechanism. Furthermore, the phthalic acid based WLMs are found to exhibit intriguing reversible pH-responsive behaviors, which include promptly switching between a high elastic system and a low viscosity fluid by pH control. The o-EAPA system possesses a larger viscosity maximum, which produces more precipitous viscosity changes as the pH varies. This study is beneficial for the formation of pH-responsive WLMs and to determine their advantages for applications.

12.
Soft Matter ; 14(24): 5031-5038, 2018 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-29862407

RESUMO

Responsive wormlike micelles are very useful in a number of applications, whereas it is still challenging to create dramatic viscosity changes in anionic surfactant systems. Here a differential pH-responsive wormlike micelle based on sulfonic surfactants was developed, which is formed by mixing sodium dodecyl trioxyethylene sulphate (SDES) and ethylenediaminetetraacetic acid tetrasodium (EDTA4-·4Na+) at the molar ratio of 1 : 1. The phase behavior, aggregate microstructure and viscoelasticity of the SDES/EDTA4-·4Na+ solution were investigated via macroscopic observation, cryo-TEM and rheological measurements. It was found that the phase behavior of the SDES/EDTA4-·4Na+ solution undergoes transitions from a water-like fluid to viscoelastic upon decreasing the pH. On decreasing the pH from 12.01 to 3.27 by adding HCl, the viscosity of the transparent solutions with wormlike micelles was increased rapidly and reached ∼3100 mPa s. Furthermore, on increasing the pH by adding NaOH, the viscosity was slightly increased due to the addition of Na+. However, the increase in the concentration of Na+ is much smaller than the theoretical addition. The same phenomenon was noted in the sodium citrate solution, but does not exist in the sodium formate system. The viscosity of the micellar solution has a sensitive response to inorganic acids and tolerance to inorganic bases due to the characteristics of polybasic acids.

13.
Soft Matter ; 13(40): 7425-7432, 2017 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-28967008

RESUMO

Wormlike micelles (WLMs) have been observed in a wide variety of cationic surfactants. Here we developed WLMs based on an N-allyl substituted cationic surfactant with an unsaturated C22-tail, N-erucamidopropyl-N,N-dimethyl-N-allyl-ammonium bromide (EDAA), and compared them with UC22AMPM at the same concentration. The viscoelasticity, aggregate microstructure and salt tolerance of EDAA solutions were investigated by rheology, surface tension and Cryo-TEM measurements. It was found that EDAA exhibited a higher viscosity and a high salt tolerance. Upon increasing the concentration of NaCl, the viscosity of wormlike micelles in the solutions continuously increased and reached ∼1.10 × 106 mP s at 200 mM. On further increasing the NaCl concentration to 2000 mM, the viscosity remained at ∼106 mP s without any reduction. But the viscosity of UC22AMPM solutions showed a drastic change with the increase of NaCl concentration. This drastic variation in rheological behavior is attributed to the presence of the N-allyl substituent. Besides, the EDAA also shows some advantages such as low overlapping concentration(∼2.2 mM) and stable viscosity over the whole pH range.

14.
Soft Matter ; 13(6): 1182-1189, 2017 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-28098315

RESUMO

Responsive wormlike micelles are very useful in a number of applications, whereas it is still challenging to create dramatic viscosity changes in wormlike micellar systems. Here we developed a pH-responsive wormlike micellar system based on a noncovalent constructed surfactant, which is formed by the complexation of N-erucamidopropyl-N,N-dimethylamine (UC22AMPM) and citric acid at the molar ratio of 3 : 1 (EACA). The phase behavior, aggregate microstructure and viscoelasticity of EACA solutions were investigated by macroscopic appearance observation, rheological and cryo-TEM measurements. It was found that the phase behavior of EACA solutions undergoes transition from transparent viscoelastic fluids to opalescent solutions and then phase separation with white floaters upon increasing the pH. Upon increasing the pH from 2.03 to 6.17, the viscosity of wormlike micelles in the transparent solutions continuously increased and reached ∼683 000 mPa s at pH 6.17. As the pH was adjusted to 7.31, the opalescent solution shows a water-like flowing behaviour and the η0 rapidly declines to ∼1 mPa s. Thus, dramatic viscosity changes of about 6 magnitudes can be triggered by varying the pH values without any deterioration of the EACA system. This drastic variation in rheological behavior is attributed to the pH dependent interaction between UC22AMPM and citric acid. Furthermore, the dependence on concentration and temperature of the rheological behavior of EACA solutions was also studied to assist in obtaining the desired pH-responsive viscosity changes.

15.
Trop Med Int Health ; 20(8): 1073-80, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25877338

RESUMO

OBJECTIVE: To assess the feasibility and results of screening of patients with DM for TB in routine community health services in China. METHOD: Agreement on how to screen patients with DM for TB and monitor and record the results was obtained at a stakeholders meeting. Subsequent training was carried out for staff at 10 community health centres, with activities implemented from June 2013 to April 2014. Patients with DM were screened for TB at each clinical visit using a symptom-based enquiry, and those positive to any symptom were referred to the TB clinic for TB investigation. RESULTS: A total of 2942 patients with DM visited these ten clinics. All patients received at least one screening for TB. Two patients were identified as already known to have TB. In total, 278 (9.5% of those screened) who had positive TB symptoms were referred for TB investigations and 209 arrived at the TB centre or underwent a chest radiograph for TB investigation. One patient (0.5% of those investigated) was newly diagnosed with active TB and was started on anti-TB treatment. The TB case notification rate of those screened was 102/100,000. CONCLUSION: This pilot project shows it is feasible to carry out TB screening among patients with DM in community settings, but further work is needed to better characterise patients with DM at higher risk of TB. This may require a more targeted approach focused on high-risk groups such as those with untreated DM or poorly controlled hyperglycaemia.


Assuntos
Instituições de Assistência Ambulatorial , Serviços de Saúde Comunitária , Diabetes Mellitus Tipo 2/complicações , Programas de Rastreamento/métodos , Saúde Pública/métodos , Tuberculose Pulmonar/diagnóstico , Adulto , Idoso , China , Diabetes Mellitus , Feminino , Humanos , Hiperglicemia/complicações , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Prevalência , Encaminhamento e Consulta , Tuberculose/complicações , Tuberculose/diagnóstico , Tuberculose/epidemiologia , Tuberculose Pulmonar/complicações , Tuberculose Pulmonar/epidemiologia
16.
Soft Matter ; 10(25): 4506-12, 2014 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-24817411

RESUMO

We report in this work the phase behavior and microstructures in a mixture of an anionic Gemini surfactant, sodium dilauramino cystine (SDLC), and a conventional cationic surfactant, dodecyl trimethyl ammonium chloride (DTAC). Observation of the appearance shows that the phase behavior of the SDLC-DTAC mixed cationic surfactant system transforms from an isotropic homogeneous phase to an aqueous surfactant two-phase system (ASTP) and then to an anisotropic homogeneous phase with the continuous addition of DTAC. The corresponding aggregate microstructures are investigated by rheology, dynamic light scattering, transmission electron microscopy and polarization microscopy. It has been found that a wormlike micelle, in the isotropic homogeneous phase, occurs linear to the branch growth. The aggregate microstructures in the ASTP lower and upper phases are branched wormlike micelles and vesicles, respectively. The micelle transformed into a vesicle upon varying the phase volume percentage until a lamellar liquid crystal formed in the anisotropic homogeneous phase. The macroscopic phase behavior and microscopic aggregate structure are related to the understanding of the possible mechanisms for the above phenomena.

17.
Front Aging Neurosci ; 15: 1237001, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37854033

RESUMO

Objective: To investigate whether paravertebral block reduces postoperative delirium (POD)/delayed neurocognitive recovery (DNR) in adults after major surgery with general anesthesia. Methods: For this systematic review and meta-analysis, we searched online databases PubMed, EMBASE, CENTRAL, and Web of Science till March 19th, 2023 to examine studies which use paravertebral block (PVB) for perioperative neurocognitive disorder. Primary and secondary outcomes were identified for the incidence of perioperative neurocognitive disorder. We did not restrict the follow-up duration of the included studies. Statistical analysis was performed to calculate mean difference (MD), Odd ratios (OR) and CI between RCTs. The quality of the evidence was assessed with the Cochrane risk of bias tool. The registration number of the study in PROSPERO is CRD42023409502. PROSPERO is an international database of prospectively registered systematic reviews. Registration provides transparency in the review process and it helps counter publication bias. Results: Total 1,225 patients from 9 RCTs were analyzed. The incidence of POD [Odds Ratio (OR) = 0.48, 95% CI 0.32, 0.72; p = 0.0004; I2 = 0%] and DNR [OR = 0.32, 95% CI 0.13, 0.80; p = 0.01; I2 = 0%] were significantly reduced in PVB group. The analysis showed no significant differences in postoperative MMSE scores [MD = 0.50, 95% CI -2.14, 3.15; p = 0.71; I2 = 98%]. Paravertebral block analgesia reduces pain scores and/or opioid use after surgery. Additionally, blood pressure was significantly lower in the PVB group, intraoperatively [MD = -15.50, 95% CI -20.71, -10.28; p < 0.001; I2 = 12%] and postoperatively [MD = -5.34, 95% CI -10.65, -0.03 p = 0.05; I2 = 36%]. Finally, PVB group had significantly shorter hospital stays [MD = -0.86, 95% CI -1.13, -0.59; p < 0.001; I2 = 0%]. Conclusion: Paravertebral block analgesia may prevent perioperative POD/DNR in patients undergoing major surgery. Further research with large sample sizes is required to confirm its effectiveness.

18.
Adv Colloid Interface Sci ; 301: 102617, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35217257

RESUMO

Improved oil recovery (IOR) includes enhanced oil recovery (EOR) and other technologies (i.e. fracturing, water injection optimization, etc.), have become important methods to increase the oil/gas production in petroleum industry. However, conventional flooding systems always encounter the problems of low efficiency, high cost and complicated synthetic procedures for harsh reservoirs conditions. In recent decades, the supramolecular interactions are introduced into IOR processes to simplify the synthetic procedures, alter their structures and properties with bespoke functionalities and responsiveness suitable for different conditions. Herein, we primarily review the fundamentals of several supramolecular interactions, including hydrophobic association, hydrogen bond, electrostatic interaction, host-guest recognition, metal-ligand coordination and dynamic covalent bond from intrinsic principles and extrinsic functions. Then, the descriptions of supramolecular interactions in IOR processes from categories and advances are focused on the following variables: polymer, surfactant, surfactant/polymer (SP) complex for EOR and viscoelasticity surfactant (VES) for clean hydraulic fracturing aspects. Finally, the field applications, challenges and prospects for supramolecular interactions in IOR processes are involved and systematically addressed. The development of supramolecular interactions can open the way toward adaptive and evolutive IOR technology, a further step towards the cost-effective production of petroleum industry.


Assuntos
Polímeros , Tensoativos , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Polímeros/química , Água
19.
Adv Colloid Interface Sci ; 299: 102527, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34607652

RESUMO

Microemulsion, because of its excellent interfacial tension reduction and solubilization properties, has wide range of applications in the petroleum industry, especially in improved oil recovery (IOR). Herein, the concept, types and formation mechanism of microemulsion were primarily introduced. Then, the preparation and characterization methods were illustrated. Additionally, several effect factors were elaborated specifically based on the composition of microemulsion. Finally, the application of microemulsion in IOR was addressed, including IOR mechanism analysis based on sweep efficiency and displacement efficiency, injection method (microemulsion flooding, in-situ microemulsion formation) and field tests. Furthermore, the current challenges and prospects of microemulsion on IOR were analyzed.

20.
J Colloid Interface Sci ; 608(Pt 1): 893-902, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34785464

RESUMO

Responsive wormlike micelles (WLMs) consisted of cationic surfactants and organic-acids are fascinating due to their reversible molecular recognition properties. However, it is unknown how the structure of organic-acids alters the stimuli-responsiveness of WLMs systems. Herein, the peculiar nature of temperature-responsive behaviors in three WLMs systems were systematically investigated. These were manufactured by combining N-erucamidopropyl-N,N-dimethylamine (UC22AMPM) with isomers of organic-acids: o-phthalic acid (o-PA), m-phthalic acid (m-PA) and p-phthalic acid (p-PA) at molar ratio of 2:1 (named as o-EAPA, m-EAPA and p-EAPA respectively). The phase behaviors, macro- and micro-rheology, as well as the mechanism of temperature-responsiveness were explored by visual inspection, rheological and optical methods. The results showed that the three systems exhibited different responsiveness with increase of temperature. Among them, the viscosity and viscoelasticity of o-EAPA were gradually decreased with temperature increase from 30 °C to 90 °C. On the other hand, those of p-EAPA were firstly increased and subsequently decreased, exhibiting the highest viscosity during the heating process. This peculiar phenomenon was attributed to the hydrophilic difference of organic-acids isomers, leading to variations of micelle transitions upon temperature increase. This study is the first report of aromatic-acids isomers inducing different on temperature-responsiveness, and finding beneficial for the development of responsive WLMs for different applications.


Assuntos
Micelas , Tensoativos , Reologia , Temperatura , Viscosidade
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