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The incidence of type 2 diabetes is high, and the existing metformin hydrochloride (MH) tablets of 250 mg cannot meet the demands of the Chinese drug market. This study aimed to evaluate the bioequivalence and safety of generic formulations of MH tablets (test formulation [T], 250 mg/tablet) and innovative products (reference formulation [R], 250 mg/tablet) under fasting conditions. This was an open‐label, single‐dose, 2‐period, 2‐sequence crossover, single‐center, randomized phase I clinical trial. T and R were considered bioequivalent if the adjusted geometric mean ratios (GMRs) and 90% confidence intervals of the area under the curve (AUC) and maximum concentration (Cmax) were within the range of 0.8‐1.25. Thirty‐five participants completed the trial. The T/R adjusted GMRs (95.7% for Cmax, 98.7% for AUC0→t, 98.8% for AUC0→∞) were within the acceptable bioequivalence range of 80%‐125%. No serious adverse events or suspected or unexpected serious adverse reactions occurred during this trial. The study findings confirmed that generic MH is a well‐tolerated and bioequivalent alternative to innovative products under fasting conditions in healthy Chinese participants. (www.chinadrugtrials.org.cn; registration no. CTR20190356) [ABSTRACT FROM AUTHOR]

Background and Purpose: Osteoarthritis (OA) pain remains a major clinical problem. It is urgent to identify novel therapeutic approaches for OA pain states. Bromodomain and extra-terminal (BET) protein inhibitors have robust anti-inflammatory effects in several pain models. However, the underlying mechanisms of these inhibitors in OA pain have not been determined. We, therefore, investigated the effects and the underlying mechanism(s) of BET inhibition on pain-related behaviours in a rat model of OA. Experimental Approach: The OA model was established by intra-articular injection of monosodium iodoacetate (MIA) in rat knees. Pain behaviours were assessed in rats by hindlimb weight-bearing asymmetry, mechanical allodynia and thermal hyperalgesia. Possible mechanisms underlying BET inhibition were explored in the MIAinduced OA pain model in the spinal cord and dorsal root ganglia (DRG). Key Results: Inhibiting bromodomain-containing protein 4 (Brd4) with either JQ1 or MS417, or using AAV2/9-shRNA-Brd4-EGFP-mediated knockdown of Brd4 genes, significantly attenuated MIA-induced pain behaviours. Brd4 inhibition suppressed NF-κB and NF-κB-mediated inflammatory cytokines in both the spinal cord and DRG in rats with MIA-induced OA pain. Brd4 inhibition also attenuated the oxidative stress and promoted nuclear factor erythroid-2-related factor 2 (Nrf2)-dependent antioxidant genes in both the spinal cord and DRG in our odel of MIA-induced OA pain. Conclusions and Implications: In conclusion, Brd4 inhibition alleviated MIA-induced OA pain in rats, via suppression of neuroinflammation and activation of Nrf2-mediated antioxidant signalling. Although our model does not perfectly represent how OA develops in humans, inhibition of Brd4 may provide novel insights into possible treatments for OA pain. [ABSTRACT FROM AUTHOR]

Background. Washed microbiota transplantation (WMT) as the improved methods of fecal microbiota transplantation has been employed as a therapeutic approach for ameliorating symptoms associated with autism spectrum disorder (ASD). In this context, colonic transendoscopic enteral tubing (TET) has been utilized as a novel procedure for administering WMT. Methods. Data of children with ASD who received WMT by TET were retrospectively reviewed, including bowel preparation methods, TET operation time, success rate, tube retention time, the comfort of children, adverse events, and parent satisfaction. Results. A total of 38 participants underwent 124 colonic TET catheterization procedures. The average time of TET operation was 15 minutes, and the success rate was 100% (124/124). There was no significant difference in TET operation time between high-seniority physicians and low-seniority physicians. In 123 procedures (99%), the TET tube allowed the completion of WMT treatment for 6 consecutive days. In 118 procedures (95.2%), the tube was detached spontaneously after the end of the treatment course, and the average TET tube retention time was 8 days. There was no incidence of tube blockage during the treatment course. No severe adverse events occurred during follow-up. Parents of all participants reported a high level of satisfaction with TET. Conclusion. Colonic TET is a safe and feasible method for WMT in children with ASD. [ABSTRACT FROM AUTHOR]

Construction of sub‐5 nm long‐range ordered structures through self‐assembly has received increasing attention. Herein, a series of ODMS‐based thermotropic liquid crystals (LCs) containing perylene diimide (PDI) were designed and synthesized. These LCs can form ordered nanostructures with periodic sizes around 5 nm including smectic J (SmJ), oblique columnar (Colob), and hexagonal columnar (Colh) phases with change in the volume fraction of ODMS, where the layer spacing of the SmJ phase is less than 5 nm. Thin films with parallel oriented nanolines with line width less than 5 nm can be obtained on PDMS‐modified silicon substrates by spin‐casting and simple thermal annealing processes. Moreover, owing to the strong π‐π interaction between PDI cores, these nanolines are long‐range ordered with uniaxial orientation in relatively large areas (1.5×1.5 μm2) with over 300 continuous microdomains without pre‐patterning. These nanostructures provide the possibility of preparing nanotemplates by oxygen plasma etching. [ABSTRACT FROM AUTHOR]

The preparation of 3D functional isolated mesoscopic assemblies remains a challenge in the self‐assembly of polymers. Here, well‐defined 3D hexagonal and hexagram prisms with uniform dimensions are acquired by the crystallization of the inclusion complex composed of a crystalline molecule tris‐o‐phenylenedioxycyclotriphosphazene (TPP) and a block copolymer. The crystalline TPP plays an important role in the self‐assembling process. The faceted morphologies of the hexagonal and hexagram prisms are infrequent in the self‐assembly field of soft materials. The formation of the prisms experiences a 3D growth mechanism. The epitaxial growth, accompanied by the heterogeneous nucleation in the edges, yields the growth of inclusion crystals. This study provides a path to construct well‐defined polymeric soft materials with broad utility based on numerous supramolecular complexes. [ABSTRACT FROM AUTHOR]

Summary: The robust cell wall structure of Haematococcus pluvialis (H. pluvialis) consists of polysaccharides and tough non‐hydrolysable sporopollenins, which makes it difficult to extract superpotent antioxidant, astaxanthin from these cells. Therefore, breakdown of cell wall is a key step in the overall process of astaxanthin recovery. In this study, the mechanism of three well‐established chemical techniques for cell disruption of H. pluvialis cysts [ionic liquids (IL), hydrochloric acid (HCl) and multiple enzymes (multi‐enzyme, ME)] on deconstruction of the cyst cell wall of H. pluvialis was explored and characterised by Fourier transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD), nuclear magnetic resonance (NMR) and gas chromatography–mass spectrometry (GC‐MS) analyses. The results demonstrated that the three cell wall breakdown techniques exhibited high extraction efficacies for the recovery of astaxanthin from H. pluvialis [IL (86.71 ± 2.06%), HCl (80.52 ± 2.28%) and ME (71.08 ± 2.49%)]. However, their performances on disrupting the trilayered cell walls of H. pluvialis were significantly different, which were confirmed by distinct morphologies of the treated cell walls visualised by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Meanwhile, the results of FTIR confirmed that, to some extent, cellulose, hemicellulose and lignin in the cell walls were hydrolysed by HCl, IL and ME treatments. However, ME exhibited a less hydrolytic effect on lignin than HCl and IL. Moreover, XRD and NMR analyses implied that the amorphous region of cell wall was susceptible to hydrolysis/breakdown by the three techniques. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) is a long‐term and inflammatory disorder featured by cartilage erosion. Here, we describe nomilin (NOM), a triterpenoid with inflammation modulatory properties in variety of disorders. In this study, we demonstrated the latent mechanism of NOM in alleviating the progress of OA both in vitro and in vivo studies. The results showed that NOM pre‐treatment suppressed the IL‐1β–induced over‐regulation of pro‐inflammation factors, such as NO, IL‐6, PGE2, iNOS, TNF‐α and COX‐2. Moreover, NOM also down‐regulates the degradation of ECM induced by IL‐1β. Mechanistically, the NOM suppressed NF‐κB signalling via disassociation of Keap1‐Nrf2 in chondrocytes. Furthermore, NOM delays the disease progression in the mouse OA model. To sum up, this research indicated NOM possessed a new potential therapeutic option in osteoarthritis. [ABSTRACT FROM AUTHOR]

This study presents the methodology design and implementation of a novel feed network. This feed network consists of several ring couplers with miniaturised and wideband characteristics. The size of this coupler is significantly reduced by employing λ/6 sections and open stubs. Besides, wideband performance is achieved by introducing a phase inverter. Compared to traditional ring couplers, the size of the proposed coupler is reduced by nearly 90%, and the relative bandwidth (BW) of the demonstrated ring coupler can reach about 80%. Owing to the miniaturised size and wideband characteristics of this ring coupler, this kind of feed network is much smaller than traditional ones with similar BW. On the basis of this feed network, a monopulse array and a low side-lobe level array is designed and fabricated. Good agreements are achieved between simulations and measurements. [ABSTRACT FROM AUTHOR]

Abstract: The self‐assembly of a rod–coil amphiphilic block copolymer (ABCP) led to Im 3 ‾ m and Pn 3 ‾ m polymer cubosomes and p6mm polymer hexasomes. This is the first time that these structures are observed in a rod–coil system. By varying the hydrophobic chain length, the initial concentration of the polymer solution, or the solubility parameter of the mixed solvent, head–tail asymmetry is adjusted to control the formation of polymer cubosomes or hexasomes. The formation mechanism of the polymer cubosomes was also studied. This research opens up a new way for further study of the bicontinuous and inverse phases in different ABCP systems. [ABSTRACT FROM AUTHOR]

The effect of thermal aging on aramid composites was assessed in this study. Poly(vinyl butyral)/phenol formaldehyde (PVB/PF) resin was used to prepare the aramid composites, which were programmed at 70, 90, 120, and 150°C for various periods of time up to 2,688 h. The microstructures and aging mechanisms were investigated by dynamical mechanical thermal analysis, Fourier transform infrared spectroscopy, and thermogravimetric analysis. Ballistic limited velocity of composites was determined by 1.1g Fragment projectiles. The results suggest that three microphases exist in the PVB/PF system. Each phase exhibits different aging mechanisms at different aging temperatures. Reduction of ballistic limited velocity was strongly affected by aging conditions. POLYM. COMPOS., 38:252-259, 2017. © 2015 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

By making use of the host-guest interactions between the host molecule tris- o-phenylenedioxycyclotriphosphazene (TPP) and the rod-coil block copolymer (BCP) poly(ethylene oxide)- block-poly(octyl 4′-octyloxy-2-vinylbiphenyl-4-carboxylate) (PEO- b-PVBP), the supramolecular rod-rod block copolymer P(EO@TPP)- b-PVBP was constructed. It consists of a crystalline segment P(EO@TPP) with a hexagonal crystalline structure and a columnar nematic liquid-crystalline segment (PVBP). As the PVBP segments arrange themselves as columnar nematic phases, the crystalline structure of the inclusion complex P(EO@TPP), which has a smaller diameter, is destroyed. The self-assembled nanostructure is thus clearly affected by the interplay between the two blocks. On the basis of wide- and small-angle X-ray scattering analysis, we conclude that the supramolecular rod-rod BCP can self-assemble into a cylinder-in-cylinder double hexagonal structure. [ABSTRACT FROM AUTHOR]

Poly{2,5-bis[(4-butoxyphenyl)-oxycarbonyl]styrene} (PBPCS) with a re-entrant phase behavior is used to synthesize a new kind of ABC triblock copolymers (triBCPs), poly(dimethylsiloxane)- b-polystyrene- b-PBPCS (PDMS- b-PS- b-PBPCS, DSB). Two well-defined triBCPs D120S100B50 and D120S100B120 with different molecular weights (MWs) and narrow MW distributions are synthesized by sequential atom transfer radical polymerization. The volume fractions of PDMS, PS, and PBPCS in D120S100B50 are 0.24, 0.26, and 0.50, respectively, while the values in D120S100B120 are 0.14, 0.16, and 0.70, respectively. At low temperatures, PBPCS is amorphous. Both samples form a core-shell hexagonally packed cylindrical (CSH) morphology. At high temperatures, PBPCS in the triBCPs can form a liquid crystalline (LC) phase, the transformation of which can induce an order−order transition (OOT) of D120S100B120. The nanostructure changes from a CSH structure to a three-phase-four-layer lamellar structure, and the transition is thermoreversible. The sequence of the OOT is opposite to that of a coil−coil−coil triBCP. The unusual LC behavior of PBPCS plays an important role on the thermoreversible morphological transition of the triBCP. [ABSTRACT FROM AUTHOR]

Five different kinds of monofunctionalized hexa- peri-hexabenzocoronenes (HBCs) are synthesized by loading dialkyl-diphenylacetylenes and asymmetric diphenylacetylene derivatives at the same time. This method shortens the synthetic route by half, with four fewer steps compared with the commonly used approach. In addition, this method is more economic and environmentally friendly. The self-assembling properties of the molecules are greatly influenced by the substituted alkyl side chains. From the short linear hexyl chain (C6) to the longer n-dodecyl (C12) chain and then to the branched alkyl chain (C10,6), the transition temperature from the crystalline phase to the liquid crystalline (LC) phase and that from the LC phase to the isotropic (Iso) state both decrease. Furthermore, the ester group far away from the aromatic core and its length are also important variables to control the phase behaviors of the molecules. The typical long-range ordered hexagonal lattice (Colh phase) is found for all the monofunctionalized molecules in their LC states. [ABSTRACT FROM AUTHOR]

Compared with aramid fabrics, ultrahigh molecular weight polyethylene fiber unidirectional (UHMWPE UD) composites have higher ballistic limited velocity at the same areal density, making UHMWPE UD composites better candidate materials for the design of body armor against ballistic and stab impact. In this study, UHMWPE UD composites impregnated with thermoplastic films were prepared, and a novel methodology was proposed to evaluate the stab-resistant performance of these composites using the concept of stab impact. Stab-resistant performance is strongly affected by stab impact parameters, such as stab velocity or impact energy, layers of UD, and stab angle. Results show that the stab-resistant performance of composites can be significantly improved by thermoplastic films, particularly polyethylene terephthalate and polypropylene films. The structure of UD composites functions importantly in enhancing stab resistance. [ABSTRACT FROM AUTHOR]

ABSTRACT Rod-coil-rod triblock copolymers, poly[4′-(methoxy)-2-vinylbiphenyl-4-methyl ether] - blockpolydimethylsiloxane- block-poly[4′-(methoxy)-2-vinylbiphenyl-4-methyl ether] (PMVBP- b-PDMS- b-PMVBP), were synthesized by nitroxide-mediated radical polymerization, and their hierarchically ordered structures were studied. A difunctional TEMPO macroinitiator was first synthesized by the hydrosilylation reaction between hydride-endcapped PDMS and allylic alkoxyamine. The polymerization of the monomer MVBP was triggered by the macroinitiator, resulting in a series of triblock copolymers. The molecular weights and polydispersity indexes were determined by gel permeation chromatography. Differential scanning calorimetry results demonstrate that the triblock copolymers exhibit two glass transition temperatures (−120 °C and 160 °C) that are markedly different. As revealed by small-angle X-ray scattering and transmission electron microscopy experiments, the triblock copolymers self-assemble into hierarchical structures with the liquid crystalline phase of PMVBP in the lamellar structures. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 1737-1744 [ABSTRACT FROM AUTHOR]

ABSTRACT A mesogen-jacketed liquid crystalline polymer (MJLCP) containing triphenylene (Tp) moieties in the side chains with 12 methylene units as spacers (denoted as PP12V) was synthesized. Its liquid crystalline (LC) phase behavior was studied with a combination of solution 1H NMR, solid-state NMR, gel permeation chromatography, thermogravimetric analysis, polarized light microscopy, differential scanning calorimetry, and one- and two-dimensional wide-angle X-ray diffraction. By simply varying the temperature, two ordered nanostructures at sub-10-nm length scales originating from two LC building blocks were obtained in one polymer. The low-temperature phase of the polymer is a hexagonal columnar phase (ΦH, a = 2.06 nm) self-organized by Tp discotic mesogens. The high-temperature phase is a nematic columnar phase with a larger dimension ( a′ = 4.07 nm) developed by the rod-like supramolecular mesogen-the MJLCP chain as a whole. A re-entrant isotropic phase is found in the medium temperature range. Partially homeotropic alignment of the polymer can be achieved when treated with an electric field, with the polymer in the ΦH phase developed by the Tp moieties. The incorporation of Tp moieties through relatively long spacers (12 methylene units) disrupts the ordered packing of the MJLCP at low temperatures, which is the first case for main-chain/side-chain combined LC polymers with MJLCPs as the main-chain LC building block to the best of our knowledge. The relationship of the molecular structure and the novel phase behavior of PP12V has implications in the design of LC polymers containing nanobuilding blocks toward constructing ordered nanostructures at different length scales. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 295-304 [ABSTRACT FROM AUTHOR]

The magnetic Fe-MBG/C composite scaffolds with enhanced mechanical strength and multifunctionality have been successfully prepared. The study showed that the Fe-MBG/C composite scaffolds with the porosity of ca. 80% had interconnected macropores (200-500 µm) and mesopores (3.7-4.4 nm) and significantly enhanced the compressive strength compared to the pure MBG scaffolds. Importantly, the Fe-MBG/C composite scaffolds exhibited good bioactivity and sustained drug release property. At the same time, the Fe-MBG/C composite scaffolds could generate heat to raise the temperature of surrounding environment in an alternating magnetic field due to their superparamagnetic behavior. Therefore, the magnetic Fe-MBG/C composite scaffolds could form a multifunctional platform with bone regeneration, magnetic hyperthermia, and local drug delivery and have more potential for use in the regeneration of the critical-sized bone defects caused by bone tumors. [ABSTRACT FROM AUTHOR]

A simple cocasting method has been developed to prepare magnetic mesoporous FePt/C composites with superparamagnetic FePt nanoparticles embedded in carbon walls. Furfuryl alcohol, iron(III) acetylacetonate (Fe(acac)3), and platinum(II) acetylacetonate (Pt(acac) 3) were used as the carbon and FePt nanoparticle precursors to be simultaneously incorporated into the channels of mesoporous silica SBA-15 template by the incipient wetness impregnation technique. After the polymerization of furfuryl alcohol, the carbonization in argon, and the removal of silica template, magnetic mesoporous FePt/C composites were finally obtained. Magnetic mesoporous FePt/C composites have high surface area of 1244 m²/g and narrow mesopore size distribution peaked at 4.93 nm. FePt nanoparticles were well embedded in mesoporous carbon walls, and mesoporous FePt/C composites exhibit superparamagnetic behavior. Using cytochrome c (Cyt c), myoglobin (Mb), and bovine serum albumin (BSA) as model proteins, the adsorption capacities of Cyt c, Mb, and BSA on magnetic mesoporous FePt/C composites can reach ca. 200, 162, and 121 µ g/mg, respectively. These results indicated that mesoporous FePt/C composites have potential as magnetically separable adsorbent for biomolecules separation. [ABSTRACT FROM AUTHOR]

Computational fluid dynamics techniques were used to investigate the hemodynamic effect of unequal anterior cerebral artery flow rates on the anterior cerebral and anterior communicating artery (ACA-ACOM) bifurcation. Hemodynamics have long been implicated as a major factor in cerebrovascular disease. Using an idealized 2D symmetric model of the ACA-ACOM geometry, the flow field and wall shear stress (WSS) at the bifurcation regions are assessed for pulsatile inflows with left to right flow ratios of 1 : 1, 2 : 1, 3 : 1, and 4 : 1. Unequal flow rates through the ACA parent arteries result in bifurcation of the higher flow parent stream and a shifting of the impingement points along the A2-ACOM adjoining wall toward the contralateral ACA. Cross-flow through the ACOM is generally unstable and results in increased WSS at the impingement region from the higher flow parent artery and a double amplitude peak in the WSS at the contralateral bifurcation region from local recirculation effects. These results suggest that asymmetry in ACA flow rates result in increased hemodynamic stresses at the ACA-ACOM bifurcation regions and suggest a possible factor for vessel weakening and aneurysm formation. [ABSTRACT FROM AUTHOR]

A series of novel comblike mesogen‐jacketed liquid‐crystalline graft copolymers, poly(p‐phenylene)‐g‐poly{2,5‐bis[(4‐methoxyphenyl)oxycarbonyl]styrene} (PPP‐g‐PMPCS) copolymers, have been designed and successfully synthesized by a Yamamoto coupling reaction and subsequent atom transfer radical polymerization (ATRP). 1H NMR spectroscopy, ultraviolet–visible spectra, and gel permeation chromatography (GPC) have been used to confirm the molecular structure of the macroinitiator and the copolymers. A study of the polymerization kinetics of ATRP has shown that the molecular weight of the copolymer increases linearly with the conversion of the monomer, whereas the polydispersity remains narrow (≤1.28), indicating that the ATRP of 2,5‐bis[(4‐methoxyphenyl)oxycarbonyl]styrene is well controlled. Thermogravimetric analysis and differential scanning calorimetry (DSC) measurements have indicated that the PPP‐g‐PMPCS copolymers have better thermal stabilities than the macroinitiator, and their thermal stabilities increase with increasing molecular weight. The liquid‐crystalline behavior has been examined with polarized optical microscopy, DSC, one‐dimensional wide‐angle X‐ray diffraction (1D WAXD), and two‐dimensional wide‐angle X‐ray diffraction (2D WAXD). The results show that all the comblike copolymers exhibit obvious liquid‐crystalline behaviors, even though the GPC molecular weight of the segments of poly{2,5‐bis[(4‐methoxyphenyl)oxycarbonyl]styrene} (PMPCS) have been determined to be far less than the critical value of linear PMPCS. Moreover, 1D WAXD measurements show that the temperature at which the comblike mesogen‐jacketed liquid‐crystalline copolymers can transform into a liquid‐crystalline phase is low; about 20 °C in comparison with the linear ones. 2D WAXD analysis has revealed that these comblike copolymers should be assigned to a hexatic columnar nematic (ΦHN) phase. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2543–2555, 2007 [ABSTRACT FROM AUTHOR]

In this work the authors present some evidences of defects in the popular continuous medium theories for nonequilibrium solvation. Particular attention has been paid to the incorrect reversible work approach. After convincing reasoning, the nonequilibrium free energy has been formulated to an expression different from the traditional ones. In a series of recent works by the authors, new formulations and some analytical application models for ultrafast processes were developed. Here, the authors extend the new theory to the cases of discrete bound charge distributions and present the correct form of the nonequilibrium solvation energy in such cases. A numerical solution method is applied to the evaluation of solvent reorganization energy of electron transfer. The test calculation for biphenyl–cyclohexane–naphthalene anion system achieves excellent agreement with the experimental fitting. The central importance presented in this work is the very simple and a consistent form of nonequilibrium free energy for both continuous and discrete charge distributions, based on which the new models can be established. © 2005 Wiley Periodicals, Inc. J Comput Chem 27: 368–374, 2006 [ABSTRACT FROM AUTHOR]

Describes the hemoglobin concentration (Hb) and hematocrit (HCT) of more than 1000 Tibetan and Han populations raised in the high altitudes of Qinghai, China. Absence of altitude effects at 3,200 meters above sea level on the hematological features of the two groups; Increase of Hb and HCT values of populations raised at altitudes at more than 3,800 meters; Absence of differences in hematological response patterns in both groups.

The present study was undertaken to examine Malpighian tubules of the yellow fever mosquito for the presence of gap junctions. Current was injected into one principal cell of the isolated Malpighian tubule and membrane voltage deflections were measured in 3 consecutive neighboring principal cells. By short-circuiting the transepithelial voltage with the diuretic peptide leucokinin we largely eliminated electrical coupling of the cells through the tubule lumen, leaving electrical coupling of cells intact. The analysis of an equivalent electrical circuit of the tubule yielded 342 ± 75 kΩ as the gap junction resistance, and 486 ± 83 kΩ as the non-junctional membrane resistance of a single epithelial cell. Next to circuit analysis, cable analysis yielded 392 ± 69 kΩ as the gap junction resistance, and 482 ± 58 kΩ as the non-junctional membrane resistance. The good agreement between these two methods validates our measurement of the gap junction resistance in live, intact Malpighian tubules. [ABSTRACT FROM AUTHOR]