Guest-guided anchoring patterns of cyclodextrin supramolecular microcrystals on droplet surfaces

The growth of cyclodextrin inclusion complexes (ICs) on oil/water interfaces represents a beautiful example of spontaneous pattern formation in nature. How the supramolecules evolve remains a challenge because surface confinement can frustrate microcrystal growth and give rise to unusual phase transitions. Here we investigate the self-assembly of ICs on droplet surfaces using microfluidics, which allows directly visualizing packing, wetting and ordering of the microcrystals anchored on the surface. The oil guests of distinct molecular structures can direct the assembly of the ICs and largely affect anchoring dynamics of the ICs microcrystals, leading to a range of behaviors including orientating, slipping, buckling, jamming, or merging. We discuss the behaviors observed in terms of the flexibility of the building blocks, which offers a new degree of freedom through which to tailor their properties and gives rise to a striking feature of anchoring patterns that have no counterpart in normal colloidal crystals.

[Incidence of postoperative complications in Chinese patients with gastric or colorectal cancer based on a national, multicenter, prospective, cohort study]

Objective: To investigate the incidence of postoperative complications in Chinese patients with gastric or colorectal cancer, and to evaluate the risk factors for postoperative complications. Methods: This was a national, multicenter, prospective, registry-based, cohort study of data obtained from the database of the Prevalence of Abdominal Complications After Gastro- enterological Surgery (PACAGE) study sponsored by the China Gastrointestinal Cancer Surgical Union. The PACAGE database prospectively collected general demographic characteristics, protocols for perioperative treatment, and variables associated with postoperative complications in patients treated for gastric or colorectal cancer in 20 medical centers from December 2018 to December 2020. The patients were grouped according to the presence or absence of postoperative complications. Postoperative complications were categorized and graded in accordance with the expert consensus on postoperative complications in gastrointestinal oncology surgery and Clavien-Dindo grading criteria. The incidence of postoperative complications of different grades are presented as bar charts. Independent risk factors for occurrence of postoperative complications were identified by multifactorial unconditional logistic regression. Results: The study cohort comprised 3926 patients with gastric or colorectal cancer, 657 (16.7%) of whom had a total of 876 postoperative complications. Serious complications (Grade III and above) occurred in 4.0% of patients (156/3926). The rate of Grade V complications was 0.2% (7/3926). The cohort included 2271 patients with gastric cancer with a postoperative complication rate of 18.1% (412/2271) and serious complication rate of 4.7% (106/2271); and 1655 with colorectal cancer, with a postoperative complication rate of 14.8% (245/1655) and serious complication rate of 3.0% (50/1655). The incidences of anastomotic leakage in patients with gastric and colorectal cancer were 3.3% (74/2271) and 3.4% (56/1655), respectively. Abdominal infection was the most frequently occurring complication, accounting for 28.7% (164/572) and 39.5% (120/304) of postoperative complications in patients with gastric and colorectal cancer, respectively. The most frequently occurring grade of postoperative complication was Grade II, accounting for 65.4% (374/572) and 56.6% (172/304) of complications in patients with gastric and colorectal cancers, respectively. Multifactorial analysis identified (1) the following independent risk factors for postoperative complications in patients in the gastric cancer group: preoperative comorbidities (OR=2.54, 95%CI: 1.51-4.28, P<0.001), neoadjuvant therapy (OR=1.42, 95%CI:1.06-1.89, P=0.020), high American Society of Anesthesiologists (ASA) scores (ASA score 2 points:OR=1.60, 95% CI: 1.23-2.07, P<0.001, ASA score ≥3 points:OR=0.43, 95% CI: 0.25-0.73, P=0.002), operative time >180 minutes (OR=1.81, 95% CI: 1.42-2.31, P<0.001), intraoperative bleeding >50 mL (OR=1.29,95%CI: 1.01-1.63, P=0.038), and distal gastrectomy compared with total gastrectomy (OR=0.65,95%CI: 0.51-0.83, P<0.001); and (2) the following independent risk factors for postoperative complications in patients in the colorectal cancer group: female (OR=0.60, 95%CI: 0.44-0.80, P<0.001), preoperative comorbidities (OR=2.73, 95%CI: 1.25-5.99, P=0.030), neoadjuvant therapy (OR=1.83, 95%CI:1.23-2.72, P=0.008), laparoscopic surgery (OR=0.47, 95%CI: 0.30-0.72, P=0.022), and abdominoperineal resection compared with low anterior resection (OR=2.74, 95%CI: 1.71-4.41, P<0.001). Conclusion: Postoperative complications associated with various types of infection were the most frequent complications in patients with gastric or colorectal cancer. Although the risk factors for postoperative complications differed between patients with gastric cancer and those with colorectal cancer, the presence of preoperative comorbidities, administration of neoadjuvant therapy, and extent of surgical resection, were the commonest factors associated with postoperative complications in patients of both categories.

Ejected microcrystals probe jammed states of droplets in cyclodextrin-based emulsions

The cyclodextrin (CD)-based emulsions exhibit complex instability behaviors such as rapid flocculation and creaming, and how to capture droplet dispersion states of the emulsions remains a great challenge. Here we prepare the CD-based emulsions with different oil-water volume ratios and CD concentrations by using high-pressure homogenization, and characterize the emulsion droplets by using optical microscopy and confocal laser scanning microscopy. We evaluate the effects of homogenization pressure on the stability of the emulsions, identify armored droplets with different surface features, measure interfacial concentrations of adsorbed ICs microcrystals, and observe ejection of the oil/CD inclusion complexes (ICs) microcrystals from the droplet surface. The droplet dispersion states are sensitive to the dynamic buildup and evolving morphologies of the interfacial microcrystals, and there are clear correlations between the properties of the ejected microcrystals and the characteristics of the emulsions. We ascribe the subsequent ejection of ICs microcrystals from the droplet surface to consolidation and deformation of the films formed between neighboring droplets. The ejection of the ICs microcrystals affords a simple method to detect the droplet-droplet interactions and phase transitions in the CD-based emulsions, which might be a generic feature in the broader context of the creaming processes of emulsions.

The Simultaneous Production of Two Distinct Types of Cellulose Nanocrystals

We develop a route to prepare two types of cellulose nanocrystals (CNCs, CNC1 and CNC2) from a unique biomass resource, the fruit shell of Camellia oleifera Abel (SCOA), by integrating sulfuric acid hydrolysis and high-pressure homogenization and examine the effects of hydrolysis time on characteristics of the CNCs during the process. The CNCs exhibit different evolutions in size, morphology, surface charge, and crystallinity with increasing hydrolysis time. While both the CNCs have high crystallinity, CNC1 is of rod-like character with a relatively low aspect ratio, and CNC2 exhibits a hairy appearance with a high aspect ratio. We highlight that controlled acid hydrolysis contributes to the formation of weak spots with an increased susceptibility for homogenizing cellulosic solid residues into hairy CNCs. This is a good step toward tailoring CNC properties in a conventional and scalable approach to maximize their potential applications.

Droplet Dispersion States of Cyclodextrin-Based Emulsions from Nonlinear Rheological Properties

Polymers are desirable to improve emulsion stability by stuffing them into the continuous phase. How to get information on the droplet dispersion states of the emulsions remains a challenge, as the emulsion characteristics are dictated by two intertwining components, the polymer matrix and the droplets. Herein, we use an amphiphilic polymer, gum arabic (GA), to mediate the droplet flocculation of cyclodextrin (CD)-based emulsions and compare them with our previous studies on the stabilization of CD-based emulsions by a nonamphiphilic polymer, methylcellulose (MC). We characterize the emulsions by using optical microscopy, confocal laser scanning microscopy, and laser particle analysis, explore their rheological behavior through large-amplitude oscillatory shear experiments, and analyze the nonlinear viscoelasticities through Fourier transform (FT)-rheology and Lissajous-Bowditch plots. There is a great difference between GA and MC in the viscosity effect and the arrangement around emulsion droplets. GA is not an effective flocculation inhibitor due to a bridging flocculation mechanism rather than a direct viscosity effect. Our analysis highlights the role of the intrinsic nonlinearity parameter (Q₀) extracted by FT analysis in reflecting the droplet dispersion states of the emulsions by decoupling structural contributions from the polymers and the emulsion droplets.

Stress buffering in cyclodextrin-based membranes coated on emulsion droplet surfaces

Surface instability of membranes not only plays a critical role in the morphological evolution observed in natural and biological systems, but also underpins a promising way for the bottom-up fabrication of novel functional materials. There is an urgent need for the design of novel building blocks into membranes, and the understanding of the abilities of the membranes to cope with mechanical stress is therefore of considerable importance. Here, we design membranes built with cyclodextrin-oil inclusion complexes, which are formed spontaneously at the oil/water interface by a self-assembly process. We select the oil phases of distinct molecular structures, namely, branched triglyceride oil and straight-chain n-dodecane, and examine the patterns in which the membranes adopt morphological transitions to buffer stress. We discuss two possible buffering scenarios for the behaviors observed in view of structural arrest and interfacial rheology, which are most closely linked to the rigidity of the membranes. The membranes represent fascinating models and shed some light on the origin of arrested stress relaxation.

Bulk and Interfacial Contributions to Stabilization of Cyclodextrin-Based Emulsions Mediated by Bacterial Cellulose

Cyclodextrin (CD)-based emulsions have a characteristic of rapid droplet flocculation, which limits their application as functional material templates, so it is very important to improve the stability of CD-based emulsions. In this study, we select bacterial cellulose (BC) as a nonadsorbing inhibitor to prevent flocculation of CD-based emulsions. We map a phase diagram of the aqueous dispersions of CD inclusion complexes (ICs) and BC from morphological observations and investigate the effects of BC on properties of the IC-laden films. We further explore the effects of BC concentration on the stability of the CD-based emulsions and investigate rheological behavior of the emulsions through large-amplitude oscillatory shear experiments. It shows that BC can effectively suppress the flocculation of CD-based emulsion droplets even at a concentration as low as 0.01 wt %. We propose that BC has dual effects from bulk and interfacial contributions on increasing emulsion stability. At low concentrations, BC mainly results in higher packing density of ICs on the emulsion droplet surface through excluded volume repulsion, and at high concentrations, BC creates a network structure that confines the motion of emulsion droplets and retards flocculation.

Microstructure and physiochemical properties of meat sausages based on nanocellulose-stabilized emulsions

Here we prepared some meat sausages using soybean oil in pure liquid form or pre-emulsified form stabilized with nanocelluloses (NCs) to partially replace pork back-fat and investigated the effects of NC types (sisal cellulose nanofiber, cotton cellulose nanofiber, and cotton cellulose nanocrystal) on the physicochemical properties and microstructure of the sausages. The physicochemical properties, including cooking loss, water holding capacity (WHC), textural properties, and rheological behavior, were evaluated. The results show that the sausages with pre-emulsified oil exhibited much-improved water and fat binding capacities, with significantly increased hardness, springiness, and chewiness. Additionally, pre-emulsifying soybean oil provided a more compact structure with smaller cavities. The sausages with different NCs had no significant difference in textural and microstructural properties, whereas they presented different water and fat binding capacities. From the results, it is concluded that NC-based emulsions are a viable fat replacer for meat sausages by providing similar stability and textural attributes.

Droplet clustering in cyclodextrin-based emulsions mediated by methylcellulose

Rapid droplet aggregation in cyclodextrin (CD)-stabilized emulsions limits their practical use as material templates. Herein, we formulate mixtures of submicron CD-based emulsion droplets suspended in aqueous solutions of methylcellulose (MC) with various concentrations and molecular weights. We evaluate the effects of MC on the microstructure and stability of the emulsions using different techniques including optical microscopy, laser particle analysis, confocal laser scanning microscopy and multiple light scattering, explore the rheological behavior of the emulsions through large amplitude oscillatory shear experiments, and study the viscoelastic nonlinearities of the emulsions as a function of strain and strain-rate space through nondimensional elastic and viscous Lissajous-Bowditch plots. It is demonstrated that the emulsion droplets are present in the form of small clusters and their size is almost independent of MC concentration and molecular weight. The clustering pattern is also supported by the changes in viscoelastic properties of the emulsions and the intracycle nonlinear behavior of the Lissajous-Bowditch plots. We propose for the first time that glass-like dynamic arrest takes place with the formation of small equilibrium droplet clusters in the situation where the CD-based emulsion droplets are forced by depletion flocculation and kinetic trapping simultaneously exerted by MC.

Driving Forces for Accumulation of Cellulose Nanofibrils at the Oil/Water Interface

Understanding the adsorption and organization of nanocelluloses at oil/water interfaces is crucial to develop a promising route to fabricate functional materials from the bottom-up. Here, we prepare acetylated cellulose nanofibrils (CNFs) with 2 degrees of substitution and investigate their assembly behavior at the oil/water interface. We study the adsorption process by tracking the dynamic interfacial tension using pendant drop tensiometry and further characterize the viscoelasticity of the CNF interfacial films as a function of ionic strength. The results show that the adsorption of the CNFs at the interface is dominated by energy barriers associated with electrostatic repulsion. With the addition of NaCl, the fibrils are rapidly accumulated at the oil/water interface and jammed into a solidlike film. The overall accumulation of the fibrils is related to the competition between van der Waals attractive forces and electrostatic repulsive forces according to the Derjaguin-Landau-Verwey-Overbeek theory. By screening on the fibril-fibril and fibril-interface electrostatic repulsive forces, the salt addition facilitates the formation of packed fibril clusters and the development of the clusters into a solidlike film. Moreover, the salt addition is assumed to trigger an abrupt density fluctuation in the vicinity of the interface (the formation of locally dense clusters and voids), leading to an increase in brittleness of the film.

Decoupling Arrest Origins in Hydrogels of Cellulose Nanofibrils

Colloidal gels with various architectures and different types of interactions provide a unique opportunity to shed light on the interplay between microscopic structures and mechanical properties of soft glassy materials. Here, we prepare acetylated cellulose nanofibrils with 2 degrees of substitution and make a structural and rheological characterization of their hydrogels. Two-step yielding processes are observed in the shear experiments, which allow us to deduce more precise knowledge regarding localized structural changes of the fibrils. We separate the viscoelastic response into two contributions: the establishment of cross-linked clusters on a fibril level and the arrested phase separation on a cluster level. We hypothesize that with the addition of salt, the hydrogels exhibit different arrested states that are identified as unable to access the thermodynamic equilibrium. Our results highlight that the coexistence of gelation and glass transitions are experimentally recognized in the hydrogels, with a global gelation driven by a local glasslike arrest during spinodal decomposition.

Shear-Induced Breakup of Cellulose Nanocrystal Aggregates

The flow properties of two kinds of cellulose nanocrystal (CNC) rods with different aspect ratios and similar zeta potentials in aqueous suspensions have been investigated. The aqueous CNC suspensions undergo a direct transition from dilute solution to colloidal glass instead of phase separation with the increasing CNC concentration. The viscosity profile shows a single shear-thinning behavior over the whole range of shear rates investigated. The shear-thinning behavior becomes stronger with the increasing CNC concentration. The viscosity is much higher for the unsonicated suspension when compared with the sonicated suspensions. The CNC rods appear arrested without alignment with an increasing shear rate from the small-angle light scattering patterns. The arrested glass state results from electric double layers surrounding the CNC rods, which give rise to long-ranged repulsive interactions. For the first time, we demonstrate that, within a narrow range of CNC concentrations, a shear-induced breakup process of the CNC aggregates exists when the shear rate is over a critical value and that the process is reversible in the sense that the aggregates can be reformed. We discuss the competition between the shear-induced breakup and the concentration-driven aggregation based on the experimental observations. The generated aggregate structure during the breakup process is characterized by a fractal dimension of 2.41. Furthermore, we determine two important variables-the breakup rate and the characteristic aggregate size-and derive analytical expressions for their evolution during the breakup process. The model predictions are in quantitative agreement with the experimental results.

Effect of sucrose fatty acid esters with different hydrophilic-lipophilic balance values on pasting and rheological properties of waxy rice flour

Effects of sucrose fatty acid esters (SEs) with hydrophilic-lipophilic balance (HLB) values of 5 (S-570), 9 (S-970), and 15 (S-1570) on the pasting and rheological properties of waxy rice flour (WRF) were investigated. Rapid Visco Analyzer (RVA) showed that addition of SEs affected the pasting properties of WRF. Rheological experiment includes the steady shear flow characteristics, and dynamic viscoelastic properties were also determined using a controlled-stress rheometer. The steady shear tests demonstrated that the viscosity data fitted well with the power law model (R ²≥0.976) and all WRF pastes exhibited typical pseudoplastic and shear-thinning properties. Dynamic rheological measurements revealed that the addition of S-970 and S-1570 significantly increased the values of G' and G″ of samples, whereas the addition of S-570 decreased these values. The addition of S-1570 reduced the value of tanδ, whereas S-570 and S-970 increased it.

Blocking and Blending: Different Assembly Models of Cyclodextrin and Sodium Caseinate at the Oil/Water Interface

The stability of cyclodextrin (CD)-based emulsions is attributed to the formation of a solid film of oil-CD complexes at the oil/water interface. However, competitive interactions between CDs and other components at the interface still need to be understood. Here we develop two different routes that allow the incorporation of a model protein (sodium caseinate, SC) into emulsions based on β-CD. One route is the components adsorbed simultaneously from a mixed solution to the oil/water interface (route I), and the other is SC was added to a previously established CD-stabilized interface (route II). The adsorption mechanism of β-CD modified by SC at the oil/water interface is investigated by rheological and optical methods. Strong sensitivity of the rheological behavior to the routes is indicated by both steady-state and small-deformation oscillatory experiments. Possible β-CD/SC interaction models at the interface are proposed. In route I, the protein, due to its higher affinity for the interface, adsorbs strongly at the interface with blocking of the adsorption of β-CD and formation of oil-CD complexes. In route II, the protein penetrates and blends into the preadsorbed layer of oil-CD complexes already formed at the interface. The revelation of interfacial assembly is expected to help better understand CD-based emulsions in natural systems and improve their designs in engineering applications.

Salting-out and salting-in: competitive effects of salt on the aggregation behavior of soy protein particles and their emulsifying properties

Emulsions stabilized by protein particles have gained increasing research attention due to their combined advantages of biocompatibility and superior stability. In this study, colloidal particles consisting of soy protein isolates (SPIs) prepared through a heat-treatment procedure are used to make oil-in-water emulsions at a protein concentration of 10 g L(-1) and a pH of 5.91. We investigate parallelly the effects of NaCl on the stability and rheological properties of the particle suspensions and their stabilized emulsions at salt concentrations of 0, 100 and 400 mM. The aggregation behavior of the particles is strongly dependent on the NaCl concentration, showing signs of sedimentation at low NaCl concentration (100 mM) but redispersion again at high NaCl concentration (400 mM). The extensive particle aggregation is beneficial to the formation of a continuous interfacial film for the emulsions, and hence results in a remarkable increase of creaming stability and interfacial viscoelastic moduli. The results can be explained in terms of two competitive effects of NaCl: salting-out and salting-in, which are attributed to complex electrostatic interactions between the particles as a function of NaCl concentration. The delicate balance between salting-out and salting-in provides an interesting insight into the nature of underlying protein particle interactions in aqueous suspensions and a possible mechanism for tailoring their emulsifying properties via salt effects.

The aggregation behavior of cellulose micro/nanoparticles in aqueous media

Cellulose micro/nanoparticles were obtained from cotton microcrystalline cellulose. The effect of ionic strength on the aggregation behavior of the cellulose micro/nanoparticles in aqueous media has been investigated by means of rheo-SALS.

CHOP THERAPY INDUCED MITOCHONDRIAL REDOX STATE ALTERATION IN NON-HODGKIN'S LYMPHOMA XENOGRAFTS

We are interested in investigating whether cancer therapy may alter the mitochondrial redox state in cancer cells to inhibit their growth and survival. The redox state can be imaged by the redox scanner that collects the fluorescence signals from both the oxidized-flavoproteins (Fp) and the reduced form of nicotinamide adenine dinucleotide (NADH) in snap-frozen tissues and has been previously employed to study tumor aggressiveness and treatment responses. Here, with the redox scanner we investigated the effects of chemotherapy on mouse xenografts of a human diffuse large B-cell lymphoma cell line (DLCL2). The mice were treated with CHOP therapy, i.e., cyclophosphamide (C) + hydroxydoxorubicin (H) + Oncovin (O) + prednisone (P) with CHO administration on day 1 and prednisone administration on days 1-5. The Fp content of the treated group was significantly decreased (p = 0.033) on day 5, and the mitochondrial redox state of the treated group was slightly more reduced than that of the control group (p = 0.048). The decrease of the Fp heterogeneity (measured by the mean standard deviation) had a border-line statistical significance (p = 0.071). The result suggests that the mitochondrial metabolism of lymphoma cells was slightly suppressed and the lymphomas became less aggressive after the CHOP therapy.

Imaging the redox states of human breast cancer core biopsies

Currently, the gold standard to establish benign vs. malignant breast tissue diagnosis requires an invasive biopsy followed by tissue fixation for subsequent histopathological examination. This process takes at least 24 h resulting in tissues that are less suitable for molecular, functional, or metabolic analysis. We have recently conducted redox scanning (cryogenic NADH/flavoprotein fluorescence imaging) on snap-frozen breast tissue biopsy samples obtained from human breast cancer patients at the time of their breast cancer surgery. The redox state was readily determined by the redox scanner at liquid nitrogen temperature with extraordinary sensitivity, giving oxidized flavoproteins (Fp) an up to tenfold discrimination of cancer to non-cancer of breast in our preliminary data. Our finding suggests that the identified metabolic parameters could discriminate between cancer and non-cancer breast tissues without subjecting tissues to fixatives. The remainder of the frozen tissue is available for additional analysis such as molecular analysis and conventional histopathology. We propose that this novel redox scanning procedure may assist in tissue diagnosis in ex vivo tissues.

[A study on pollen morphology of Dipsacus]

OBJECTIVE

To study the pollen morphology of Dipsacus L. produced in China.

METHOD

Examining the pollen morphology of 17 species and 2 varieties of Dipsacus L. with light microscope and scanning electron microscope.

RESULT

The shape of pollen grains is spheroidal and the aperture is tricolpate. The ornamentation of exine may be divided into 3 types: dispinulate-reticulate, dispinulate-foveolate, dispinulate-rugulate or nearly smooth.

CONCLUSION

Dipsacus is a natural class group, and the slight difference of its pollen grains is useful to some extent in the division of species.

Identification of transcriptional activation and repression domains in human CCAAT/enhancer-binding protein epsilon

Human CCAAT/enhancer-binding protein epsilon (C/EBPepsilon), a new member of the C/EBP family, significantly up-regulates both the mim-1 and human myeloperoxidase promoters, suggesting an important role for C/EBPepsilon in the transcriptional regulation of a subset of myeloid-specific genes. To elucidate the structure and function of C/EBPepsilon in transcriptional activation, amino acid residues 1-115, 147-249, or 1-249 of C/EBPepsilon were fused to the yeast GAL4 DNA binding domain. These expression vectors were cotransfected with a chloramphenicol acetyltransferase reporter gene and, in all cell lines tested, only the GAL-C/EBPepsilon-(1-115) fusion protein significantly activated expression from the chloramphenicol acetyltransferase reporter gene. Sixteen deletion mutants of C/EBPepsilon mapped the transactivation domain to amino acids 1-18 at the N terminus and revealed the presence of a transcription repression element between amino acid residues 116 and 162. Expression vectors containing the repression domain of C/EBPepsilon strongly inhibited gene transcription from TK, SV40, and adenoviral major late promoters bearing GAL4 binding sites. Fusion of this repression domain to the VP16 activation domain inhibited the transactivation function of VP16. Deletion of this repression domain increased gene transcription from a neutrophil elastase promoter-luciferase reporter. Taken together, these data suggest that C/EBPepsilon regulates transcription by utilizing both activation and repression functions.

[Pericatheter urethrography and its use in post interlocking sound urethroplasty]

21 cases of posterior urethral rupture due to pelvic fracture were treated by acute interlocking sound urethroplasty since 1982. Postoperative pericatheter urethrography was carried out to observe the recover of urethral rupture. The results showed that the time for recover of ruptured urethra varied from 4 to 13 weeks. 71% of all cases required more than 8 weeks for recovery. The patients were followed up from 1 to 9 years, and 86% of them showed satisfactory results. It is believed that pericatheter urethrography not only provides an objective proof for the recovery of ruptured urethra but also can be used as a reliable basis for the removal of stenting catheter.

[Effect of enhancers on cutaneous permeation of piroxicam in vitro]

Enhancing effects on the permeation of piroxicam (Pir) through excised hairless mouse (inbred HRS mice) skin were investigated by measuring flux. Azone 1% was found to be the most effective enhancer studied, increasing the flux about 21 times. The effect of Azone was enhanced by the presence of propylene glycol. Oleic acid, ethylacetate, and ethanol promoted the diffusion of Pir. Other enhancers, such as DMSO, PEG 400, acetone, urea and salicylic acid, showed little or no effect. Pir-beta-cyclodextrin inclusion compound increased the flux about 3 times. The results revealed that lipophilic enhancers were more effective than lipophobic ones.