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Background: Over-expression of membranous CD154 and soluble CD154 (sCD154) in T lymphocytes is important in pathogenesis of autoimmune diseases. PKC pathway induces sCD154 production through promoting shedding of membranous CD154. Objectives: Hydroxychloroquine (HCQ) has been used in the treatment of autoimmune diseases for decades. We sought to identify the effects of HCQ on sCD154 and a possibly regulatory mechanism. Methods: CD4 +T cells were isolated from the blood of healthy donor. After stimulated with ionomycin +PMA and various concentrations of HCQ, concentration of sCD154 in the medium, expression of membranous CD154, Ca2+ pathway and PKC signalling pathway were assessed. Results: HCQ attenuated intracellular sustained calcium storage release and membranous CD154 synthesis in activated T cells. Besides, HCQ inhibited PKC activation and subsequently shedding of membranous CD154. Conclusions: HCQ inhibited production of sCD154 in activated T cells through suppressing Ca2+ and PKC signalling pathway. These findings provide one of the mechanistic insights into HCQ treatment. References [1] Alaaeddine N, Hassan GS, Yacoub D, Mourad W. CD154: an immunoinflammatory mediator in systemic lupus erythematosus and rheumatoid arthritis. Clin Dev Immunol. 2012:490148. [2] Goules A, Tzioufas AG, Manousakis MN, Kirou KA, Crow MK, Routsias JG. Elevated levels of soluble CD40 ligand (sCD40L) in serum of patients with systemic autoimmune diseases. J Autoimmun2006;26:165–71. [3] Matthies KM, Newman JL, Hodzic A, Wingett DG. Differential regulation of soluble and membrane CD40L proteins in T cells. Cell Immunol. 2006;241:47–58. [4] Wu SF, Chang CB, Hsu JM, Lu MC, Lai NS, Li C, Tung CH. Hydroxychloroquine inhibits CD154 expression in CD4+ T lymphocytes of systemic lupus erythematosus through NFAT, but not STAT5, signaling. Arthritis Res Ther2017Aug 9;19(1):183. Disclosure of Interest None declared

Epidermal growth factor receptor (EGFR)-mediated cell signaling is critical for mammary epithelial cell growth and survival; however, targeting EGFR has shown no or only minimal therapeutic benefit in patients with breast cancer. Here, we report a novel regulatory mechanism of EGFR signaling that may explain the low response rates. We found that breast tumor kinase (Brk)/protein-tyrosine kinase 6 (PTK6), a nonreceptor protein-tyrosine kinase highly expressed in most human breast tumors, interacted with EGFR and sustained ligand-induced EGFR signaling. We demonstrate that Brk inhibits ligand-induced EGFR degradation through uncoupling activated EGFR from casitas B-lineage lymphoma-mediated EGFR ubiquitination. In addition, upon activation by EGFR, Brk directly phosphorylated Y845 in the EGFR kinase domain, thereby further potentiating EGFR kinase activity. Experimental elevation of Brk conferred resistance of breast cancer cells to cetuximab (an EGFR-blocking antibody)-induced inhibition of cell signaling and proliferation, whereas knockdown of Brk sensitized the cells to cetuximab by inducing apoptosis. Our findings reveal a previously unknown role of Brk in EGFR-targeted therapy.

Recent studies revealed that EDM hole-drilling strain gage method is applicable for the measurement of residual stress in materials with higher hardness and toughness. However, the metallurgical transformation layer formed on the wall of the hole induces an additional stress and therefore generates a measurement error. Usually this error can be calibrated by estimating and reducing the hole-drilling induced extra stress, σIS. However, the value of σ IS is highly sensitive to the EDM parameters. Accordingly, the current study aimed at lowering σ IS by optimizing the working parameters of pulse current, pulse-on duration and pulse-off duration with experiments. An inverse power law relationship was constructed to predict the magnitude of the hole-drilling induced stress where was referred. A convenient calibration method was proposed where calibration factor can be easily determined. The calibrated results revealed good accuracy where deviation is no more than 10 MPa. The accuracy of the proposed calibration scheme was confirmed in study.

To study the effect of dietary docosahexaenoic acid (DHA) on the expression of adipocyte determination and differentiation-dependent factor 1 (ADD1) mRNA in pig tissues, weaned, crossbred pigs (30 d of age) were fed either 2% (as-fed basis) tallow or DHA oil for 18 d. Body weight of the pigs was not affected by different dietary fatty acid (FA) compositions. The plasma and liver FA composition reflected the composition of the diet. The adipose tissue and skeletal muscle FA composition only partially reflected the diet, indicating either a slower FA turnover or that a greater proportion of the FA in these tissues is from endogenous FA synthesis. The ADD1 is an important transcription factor that modulates transcription of FA synthase to regulate the endogenous FA synthesis in the liver and adipose tissue. The ADD1 mRNA was decreased (P < 0.05) in the liver of DHA-treated pigs compared with that of the tallow-treated pigs. The diets did not have an effect on the ADD1 mRNA in pig adipose tissue. The ADD1 transcript was not detected in pig skeletal muscle. These results indicate that significant enrichment of liver DHA content inhibits the expression of ADD1 mRNA. Such an effect is similar to that reported in porcine differentiating adipocytes cultured with DHA. The liver and muscle acyl CoA oxidase mRNA concentration was increased (P < 0.05) by DHA oil treatment, suggesting that DHA treatment may increase peroxisomal fatty acid oxidation in these two tissues. Our present observations demonstrate that dietary DHA enrichment not only affects tissue DHA concentration but also mildly modifies the expression of genes related to fatty acid metabolism in the porcine liver and skeletal muscle.

Polyunsaturated fatty acids (FA) regulate genes involved in lipid metabolism. The effects of polyunsaturated FA on the transcription factor adipocyte determination and differentiation-dependent factor (ADD) 1 and fatty acid synthase (FAS) mRNA in differentiating porcine adipocytes were measured using a stromal vascular cell culture system. Porcine stromal vascular cells were isolated from subcutaneous adi-pose tissues and plated in Dulbecco's modified Eagle's medium (DMEM)–nutrient mixture F-12 Ham (F-12) plus fetal bovine serum (100 ml/l) for 24 h. Then cells were differentiated in DMEM–F12 plus insulin, hydrocortisone and transferrin without or with polyunsaturated FA at 6·25, 25·00 or 100·00 μm. The ADD1 mRNA was decreased by 100·00 μm-arachidonic acid, 6·25 to 100·00 μm-docosahexaenoic acid orcis-9,trans-11-conjugated linoleic acid. The polyunsaturated FA reduced the transcription rate of FAS, but not of ADD1. All three polyunsaturated FA accelerated degradation of ADD1 and FAS mRNA to reduce the abundance of ADD1 and FAS mRNA. Results also showed that polyunsaturated FA inhibit the ADD1 expression, not only of mRNA concentration, but also of mature ADD1 protein concentration, suggesting an overall reduction of ADD1 function by polyunsaturated FA. Our present experiments demonstrate that polyunsaturated FA regulate the gene expression of ADD1 and enzymes involved in lipid metabolism in porcine adipocytes.

The thermally-induced, fiber-alignment shifts of ferrule-solder-ferrule (FSF) joints in add/drop filter-module packaging for multiplexer/demultiplexer applications have been studied experimentally and numerically. From experimental measurements of the module-insertion loss difference (0.3 dB) with and without temperature cycling, FSF angular-tilt misalignments of up to 0.05° were found after undergoing 42 temperature cycles. The effects of an imperfect soldering process along the two ferrules during the packaging of an add/drop filter module on the angular-tilt misalignment has been explored in this study. An elastic-plastic finite-element method (FEM) was performed to evaluate the variation of thermal stresses, the distribution of residual stresses, and the angular-tilt misalignment of the FSF joints. Experimental measurements of the FSF angular-tilt misalignment were in good agreement with the FEM calculations. The major angular-tilt misalignments of FSF joints in add/drop filter-module packaging during temperature cycling may come from the localized plastic-solder yielding introduced by the local thermal-stress variation and the redistribution of the residual stresses within the solder. The FSF angular-tilt misalignment and, hence, fiber-alignment shift of the add/drop filter module under temperature-cycling tests can be reduced significantly if a perfect soldering process along the two ferrules can be fabricated.

When measuring the residual stress within a component using the electrical discharge machining (EDM) strain-gage method, a metallurgical transformation layer is formed on the wall of the measurement hole. This transformation layer induces an additional residual stress and therefore introduces a measurement error. In this study, it is shown that given an appropriate set of machining conditions, this measurement error can be compensated directly using a calibration stress factor σcal computed in accordance with the properties of the workpiece material. It is shown that for EDM machining conditions of 120 V/12 A/6 μs/30 μs (discharge voltage/pulse current/pulse-on duration/pulse-off duration), the hole-drilling induced stress reduces with an increasing thermal conductivity (k) in accordance with the relation σcal=325.5k−0.65 MPa and increases linearly with an increasing carbon equivalent (CE) in accordance with σcal=7.6×(CE)+22.4 MPa. Therefore, a given knowledge of the thermal conductivity coefficient or carbon equivalent of the workpiece material, an accurate value of the true residual stress within a component can be obtained simply by subtracting the computed value of the calibration stress from the stress value obtained in accordance with the EDM hole-drilling strain-gage method prescribed in ASTM E837.

The fatigue properties of graphite/epoxy (Gr/Ep) T300/5208 composite laminates of 16 plies with a central circular hole subjected to tension-tension (T-T) constant-stress amplitudes at room temperature and low humidity have been fully investigated. Studied are four types of notched laminates which are classified as unidirectional, off-axis, orthotropic shear and quasi-isotropic. Some of them were precracked to initiate and guide the crack growth transversely. Our work is experimental and the analysis is based on a semiempirical approach.

The effects of short-term and long-term ascorbic acid supplements on plasma alcohol clearance were studied in 13 clinically healthy male subjects. Two dose levels of alcohol, 0.5 and 0.8 g/kg body weight, were used. Blood samples were taken at zero time, 0.5 hours, then hourly up to 6 hours after alcohol consumption for the measurement of plasma alcohol and ascorbic acid levels, red-cell reduced glutathione level, and plasma alanine aminotransferase activity. At both dosages of alcohol, short-term as well as long-term pretreatment with ascorbic acid significantly enhanced the clearance of plasma alcohol. Although long-term ascorbic acid pretreatment resulted in better alcohol clearance, no significant difference in alcohol clearance was found between short-term and long-term ascorbic acid pretreatment. The two dose levels of alcohol had no significant effect on the red-cell reduced glutathione concentration or plasma alanine aminotransferase activity.

Two kinds of cecidomyiid galls induced by Daphnephila on Machilus thunbergii Sieb. & Zucc. leaves at various developmental stages, i.e., young, growing, and mature, were analyzed for their biochemical composition of photosynthetic pigment-protein complexes located in thylakoid membranes using the Thornber and MARS electrophoretic fractionation systems. Both kinds of galls were totally deficient in the pigment-protein complexes CP1, and A1, AB1, and AB2 through the whole period of gall formation. Immunoblotting of antibody against light-harvesting complex 2b (LHC2b) apoprotein confirmed this deficiency in gall’s lifetime, which never recovered under any condition. Electron microscopy demonstrated that already at the early developmental stage the gall chloroplasts had thylakoid morphology like that in a normal leaf.

To study the effect of dietary docosahexaenoic acid (DHA) on the expression of adipocyte determination and differentiation-dependent factor 1 (ADD1) mRNA in pig tissues, weaned, crossbred pigs (30 d of age) were fed either 2% (as-fed basis) tallow or DHA oil for 18 d. Body weight of the pigs was not affected by different dietary fatty acid (FA) compositions. The plasma and liver FA composition reflected the composition of the diet. The adipose tissue and skeletal muscle FA composition only partially reflected the diet, indicating either a slower FA turnover or that a greater proportion of the FA in these tissues is from endogenous FA synthesis. The ADD1 is an important transcription factor that modulates transcription of FA synthase to regulate the endogenous FA synthesis in the liver and adipose tissue. The ADD1 mRNA was decreased (P0.05) in the liver of DHA-treated pigs compared with that of the tallow-treated pigs. The diets did not have an effect on the ADD1 mRNA in pig adipose tissue. The ADD1 transcript was not detected in pig skeletal muscle. These results indicate that significant enrichment of liver DHA content inhibits the expression of ADD1 mRNA. Such an effect is similar to that reported in porcine differentiating adipocytes cultured with DHA. The liver and muscle acyl CoA oxidase mRNA concentration was increased (P0.05) by DHA oil treatment, suggesting that DHA treatment may increase peroxisomal fatty acid oxidation in these two tissues. Our present observations demonstrate that dietary DHA enrichment not only affects tissue DHA concentration but also mildly modifies the expression of genes related to fatty acid metabolism in the porcine liver and skeletal muscle.

A TD-SCDMA RF front-end receiver IC, which is fabricated in a 0.35 /spl mu/m SiGe BiCMOS technology, is presented in this paper. This IC contains two blocks, low-noise amplifier (LNA) and mixer, and operates at 2.7 V supply voltage with a current consumption of 14.7 mA. The measured NF and power gain of the IC are 2.7 dB and 31 dB, respectively. It is shown that RF front-end circuit which is implemented in a SiGe BiCMOS process has more advantages than CMOS circuits, such as power consumption and NF performance.

When using a current-commutating quadrature modulator in a wireless transmitter, undesired spurs are generated at 3f/sub LO/, 5f/sub LO/, and so on, thus requiring a good filter to suppress those unwanted signals. By using the non-ideal characteristic of the non-zero output resistance of the amplifier in a Sallen-Key filter, a second order low-pass filter with transmission zeros is proposed. In this paper, the filter is designed and simulated using a 0.35 /spl mu/m SiGe BiCMOS model provided by TSMC. The designed 4/sup th/-order low-pass filter with a parasitic pole, implemented by cascading two biquads and an amplifying stage, outperformed a 9/sup th/-order AC-coupled RC low-pass filter not only in size, but also in suppression characteristics and current consumption.

A DCS1800 offset-phase-locked-loop upconversion modulation loop integrated circuit (IC) fabricated in a 0.18-/spl mu/m CMOS technology is presented in this paper. This IC operates at 2.8-V supply voltage with a current consumption of 36 mA. The measured root-mean-square and peak phase errors of the Gaussian minimum shift keying (GMSK) transmission signal are 1.6/spl deg/ and 4/spl deg/, respectively. It is shown that such circuits can be implemented in CMOS process with current dissipation and performance comparable to BiCMOS chips. Advantages of upconversion modulation loop and design issues of I/Q modulators are also described.

Objective: To determine whether a relationship exists between perioperative fluid balance and time to drain removal. Design: Retrospective review. Setting: Tertiary care center. Patients: The medical records of all patients who underwent unilateral neck dissection over a 3-year period were reviewed. Exclusion criteria were simultaneous resection of the primary tumor, postoperative hematoma and seroma, chylous fistula, or an incomplete medical record of drain output. A total of 33 patients were included in the study. Interventions: Dissection of all 5 levels was performed on all patients. All wounds were evacuated by a closed suction system. Output was recorded every 8 hours. The drains were removed if the total output over 3 consecutive shifts totaled less than 30 mL. Main Outcome Measures: Patient variables measured included removal of drains in the sternocleidomastoid muscle, the internal jugular vein, or veins draining cranial nerve; prior radiation or chemoradiation, extracapsular extension, and history of hypertension or diabetes mellitus. Patient age, serum osmolality, hematocrit, intraoperative blood loss, intraoperative fluid administration, 24-hour fluid balance, TNM stage, and the number of positive nodes were also compared with the length of time that drainage was required. Results: Results from a t test showed a significant difference in mean number of shifts until drain removal if the sternocleidomastoid muscle was removed (11.8 shifts) or preserved (9.4 shifts) (P=.04). The Pearson correlation coefficient showed that intraoperative fluid administration (R=0.42; P=.02) and 24-hour fluid balance (R=0.38; P=.03) correlated with the length of time until drain removal. None of the other variables measured were statistically significant. Conclusions: A direct relationship exists between the amount of fluid administered during neck dissection and the length of time required for adequate wound drainage.

SummaryRats on a selenium-deficient torula yeast diet containing 100 mg Vitamin E/kg compared to a similar diet with 0.5 ppm selenium as sodium selenite do not show any decrease in protein, RNA and DNA synthesis in the pancreas or liver. The gross depression and change of pancreatic enzymes found in the chick on selenium-deficient diet were not apparent in the rat on a selenium-deficient diet.

We studied the effect of zinc deficiency on thymidine metabolism in intact and wounded rats. Zinc deficiency was associated with significantly decreased incorporation of [methyl-3H] thymidine into skin DNA of both intact and wounded rats, as shown by liquid scintillation counting and autoradiography. With wounding, proliferation--as gauged by the labeling index--increased to about twice normal for zinc-supplemented rats, but 3.5-fold for zinc-deficient rats. However, despite the increased proliferation rate, wound-healing in deficient rats was always slower than in zinc-supplemented animals. Incorporation of 3H-labeled thymidine into spleen DNA at 2 and 4 h, and liver DNA at 4 h was also significantly less in zinc-deficient rats than in zinc-supplemented rats. Conversely, DNA synthesis was enhanced in the thymus gland of zinc-deficient rats. Further studies showed that significantly higher percentages of [methyl-14C] thymidine were oxidized by zinc-deficient rats. The specific involvement of the methyl group of thymidine was indicated by the observation of normal oxidattions of [2-14C] thymidine. These findings support the view that zinc directly regulates DNA synthesis.

The effects of zinc deficiency, in rats, on the levels of free amino acid in urine, plasma and skin extract were studied. In urine, significantly higher concentrations of taurine, urea, threonine, glutamic acid, valine, isoleucine, leucine and lysine were observed in zinc-deficient rats. In plasma, however, the levels of most individual amino acids in zinc-deficient rats were about the same as those in zinc-supplemented pair-fed controls with the exception of threonine, leucine and isoleucine. These three were significantly higher in rats receiving zinc-deficient diet. On the other hand, the zinc-supplemented ad libitum-fed rats had a significantly increased concentration of taurine, aspartic acid, threonine, serine, glutamic acid, alanine, lysine and arginine than either the pair-fed zinc-supplemented rats or zinc-deficient rats. In skin extracts, threonine, valine, leucine tyrosine, lysine, methionine, cystine, aspartic acid and alanine levels were significantly lower in zinc-deficient rats as compared to zinc-supplemented ad libitum-fed controls. However, the zinc-deficient rats had the same amount of methionine, cystine and glycine as the zinc-supplemented pair-fed rats. This observation suggests that the impairment of skin protein synthesis from injected labeled amino acids in zinc-deficient rats as opposed to zinc-supplemented pair-fed controls is not related to the availability or pool size of the precursors.

Zinc has long been recognized as essential to normal growth and development in animals and in man. Its role in regulating metabolic events at the molecular level is becoming evident, but it is not yet possible to correlate biochemical function to the pathology of deficiency. Studies by a number of investigators have indicated that feeding animals with a diet low in zinc causes an abnormal condition on skin in addition to growth retardation. These include the rats (Todd et al., 1934), mice (Day and Skidmore, 1947), swine (Kernkam and Ferrin, 1953), cattle (Miller and Miller, 1962), lambs (Ott et al., 1964) goats (Miller et al., 1964), dogs (Robertson and Burns, 1963), rabbits (Graham and Telle, 1967), squirrel monkeys (Macapinlac et al., 1967), hamsters (Boquist and Lernmark, 1969), guinea pigs (McBean et al., 1972). In man (Prasad et al., 1963) the clinical aspects of zinc deficiency are remarkably similar to those described above for animals. They consisted of growth retardation and rough skin with hyperpigmentation. These observations indicate the importance of zinc in skin metabolism.