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Mixed lineage kinase 3 (MLK3), also known as MAP3K11, was initially identified in a megakaryocytic cell line and is an emerging therapeutic target in cancer, yet its role in immune cells is not known. Here, we report that loss or pharmacological inhibition of MLK3 promotes activation and cytotoxicity of T cells. MLK3 is abundantly expressed in T cells, and its loss alters serum chemokines, cytokines, and CD28 protein expression on T cells and its subsets. MLK3 loss or pharmacological inhibition induces activation of T cells in in vitro, ex vivo, and in vivo conditions, irrespective of T cell activating agents. Conversely, overexpression of MLK3 decreases T cell activation. Mechanistically, loss or inhibition of MLK3 down-regulates expression of a prolyl-isomerase, Ppia, which is directly phosphorylated by MLK3 to increase its isomerase activity. Moreover, MLK3 also phosphorylates nuclear factor of activated T cells 1 (NFATc1) and regulates its nuclear translocation via interaction with Ppia, and this regulates T cell effector function. In an immune-competent mouse model of breast cancer, MLK3 inhibitor increases Granzyme B-positive CD8(+) T cells and decreases MLK3 and Ppia gene expression in tumor-infiltrating T cells. Likewise, the MLK3 inhibitor in pan T cells, isolated from breast cancer patients, also increases cytotoxic CD8(+) T cells. These results collectively demonstrate that MLK3 plays an important role in T cell biology, and targeting MLK3 could serve as a potential therapeutic intervention via increasing T cell cytotoxicity in cancer.

We present the results of polarimetric analysis of collagen on varying pathologies of breast tissues using second-harmonic patterned polarization-analyzed reflection confocal (SPPARC) microscopy. Experiments are conducted on a breast tissue microarray having benign tissues (BT), malignant invasive lobular carcinoma (ILC), and benign stroma adjacent to the malignant tissues (called the benign adjacent tissue, or BAT). Stroma in BAT and ILC exhibit the largest parameter differences. We observe that stromal collagen readings in ILC show lower depolarization, lower diattenuation and higher linear degree-of-polarization values than stromal collagen in BAT. This suggests that the optical properties of collagen change most in the vicinity of tumors. A similar trend is also exhibited in the non-collagenous extrafibrillar matrix plus cells (EFMC) region. The three highlighted parameters show greatest sensitivity to changes in the polarization response of collagen between pathologies.

The transparent glasses with composition 30PbO–10GeO 2 –(60−x)SiO 2 −xNb 2 O 5 (mol%) (0 ≤ x ≤ 2.5) are prepared by conventional melt quenching technique. The amorphous nature of the prepared glasses is characterized by XRD. The spectroscopic studies such as optical absorption, FTIR, Raman spectra were carried out at room temperature on these glasses. Besides this electrical properties, like dielectric constant e ' , loss tan δ , ac conductivity σ a c etc., were also investigated over a moderately wide range of frequency (10 3 –10 6 Hz) and temperature (30–300 °C). The optical absorption spectrum of the prepared glasses has exhibited absorption bands around 325 nm and 340 nm and these are due to the triplet – singlet electronic transition of Ge 2+ state presents in the glass matrix as conversion of GeO 2 into GeO is much easier rather than SiO 2 . From FTIR spectra of as prepared glasses, it is noticed that the intensity of octahedral NbO 6 structural units is found to increase up to 2 mol% of Nb 2 O 5 there after it is observed to decrease. It is also supported by Raman shift of NbO 6 structural units observed around 650 and 930 cm −1 . The analysis of electrical studies is also revealed that the conductivity of prepared glasses is found to increase gradually up to 2 mol% of Nb 2 O 5 beyond this concentration it is observed to decrease. When the spectroscopic investigations are coupled with electrical studies it is concluded that the glass samples doped with 2 mol% of Nb 2 O 5 are found to exhibit good semiconducting nature among the prepared glasses. Such glasses are suitable for fabrication of solid state devices.

Transparent glass ceramics, synthesized from melt quenching followed by heat treatment, of the composition 10Na 2 O–30PbO–10Bi 2 O 3 –(50 − x )SiO 2 : x Cr 2 O 3 (mol%), where 0 ⩽ x ⩽ 0.5, were characterized with XRD, DTA, SEM and EDS. Physical and spectroscopic studies, viz., optical absorption, electron paramagnetic resonance (EPR), FTIR and Raman were investigated. The characterization of the host glass ceramic has revealed that the formation of a major phase of sodium silicate along with two minor phases such as lead silicate and bismuth oxide. By integrating Cr 2 O 3 to the host glass additional crystal phases viz., NaCrO 2 , Na 2 Cr 2 O 7 and Pb(CrO 4 ) which are the complexes of Cr 3+ and Cr 6+ ions were also developed. As the concentration of nucleating agent is increased, a part of the Cr 6+ ions is found to reduce in to Cr 3+ ions. Spectroscopic studies have revealed that with an increase in the concentration of Cr 2 O 3 from 0.1 to 0.5 mol%, there is a gradual increase in the intensity of vibrational modes of various asymmetric structural units of silicate, bismuthate and chromate in the glass ceramic network at the expense of symmetrical structural units. The analysis of the results of these studies has indicated that in the samples containing higher concentration of Cr 2 O 3 , chromium ions exists predominantly in Cr 3+ state and occupy the octahedral positions in glass ceramic matrix and such glass ceramic samples are suitable for lasing action.

Transparent glasses with the composition 20RO–10Na 2 O–69B 2 O 3 –1Fe 2 O 3 (where R = Ca, Sr and Ba) were prepared by melt quenching technique. The amorphous nature of the glass was confirmed by X-ray diffraction pattern of the sample. Physical parameters and spectroscopic studies such as EPR, optical absorption and FTIR were carried out for the glass samples. Besides dielectric properties i.e. dielectric constant (e′), and loss (tan δ), a.c. conductivity (σ ac ) in the frequency range 10 3 –10 6 Hz and the temperature range 30–300 °C in air of the present glasses were also investigated. The dielectric and spectroscopic properties have been analyzed in the light of different oxidation states of iron ions in order to understand the influence of alkaline earth oxides as modifier oxide on the structure and insulating strength/conductivity of glass matrix.

Transparent BaBiBO 4 :CoO glasses of composition 10BaO·20Bi 2 O 3 ·(70 − x )B 2 O 3 · x CoO (wt%) where 0 ⩽ x ⩽ 2.0, were synthesized and characterized by XRD. Physical properties coupled with Spectroscopic (optical absorption, photoluminescence and FTIR spectra) and dielectric studies were carried out. The area under the absorption band corresponds to 4 A 2 ( 4 F) → 4 T 1 ( 4 F) transition of Co 2+ (IV) is gradually increased up to 1.5 wt% of CoO and then it is decreased at 2.0 wt% of CoO. It is also supported by decrease in Co 2+ ion concentration N i , at 2.0 wt% of CoO calculated from density values. The concentration of luminescence centers of bismuth ions [Bi 2+ ions in the visible region] decreased up to 1.5 wt% of CoO and increased beyond this concentration. Further, it is also noted that at higher concentrations of dopant Co 2+ ions acts as redox partner of Bi 3+ and reduce it to Bi 2+ state. The optical band gap energy ( E g ) is found to increase than the pure with 0.5 wt% of CoO and beyond this concentration the E g value is gradually decreased. It is due to the formation of covalent Co–O–B bonds in the glass network with tetrahedral CoO 4 units. From FTIR studies, at higher concentrations due to gradual increase in CoO 6 units leads to formation of BO 3 and BiO 6 units along with NBOs. The above results are also supported by observed decrease in dielectric constant e ′, loss tan δ and σ ac with the initial introduction 0.5 wt% of CoO in the glass matrix at any frequency and temperature except in the relaxation temperature region.

Glasses doped with different concentrations of MoO3 (ranging from 0 to 10 mol %) in the system ZnF2–Bi2O3–P2O5 were crystallized and characterized by X-ray diffraction(XRD), scanning electron microscopy (SEM) and differential thermal analysis (DTA) techniques. The presence of BiPO4, α-Zn3(PO4)2, Bi2MoO6, γ‐Bi2MoO6, Bi2Mo2O9, MoOPO4, α-ZnMoO4 microcrystalline phases were exposed by XRD and SEM studies. The DTA indicated that the surface crystallization prevails over the bulk crystallization as the concentration of the crystallizing agent is increased. Spectroscopic properties (FTIR, Raman, optical absorption and ESR) at room temperature and dielectric properties (dielectric constant, loss tanδ, ac conductivity) over a range of frequency and temperature are studied. The IR and Raman spectra exhibit bands due to MoO4 and MoO6 units in structural groups in addition to various conventional phosphate groups. The existence of Mo5 + state in addition to Mo6 + state in these glass ceramic samples has been identified by the optical absorption, ESR and magnetic susceptibility studies. The variations observed in all these properties with the concentration of the crystallizing agent have been analyzed in the light of different oxidation states and environment of molybdenum ions in the glass ceramic network.

Transparent glasses 20ZnF2–40Bi2O3–(40 − x)GeO2:xCoO; 0 ⩽ x ⩽ 1 wt% are prepared by melt quenching technique. The amorphous nature of the samples is characterized by X-ray diffraction (XRD) and differential thermal analysis (DTA). Spectroscopic studies like optical absorption, FTIR, Raman and dielectric parameters (e′, loss tan δ, conductivity σac over a wide range of frequency and temperature as well as dielectric breakdown strength at room temperature) of these samples have been carried out. Optical absorption data has revealed that the bismuth radicals, observed in pure sample C0, are combined with cobalt ions with increase in concentration of CoO. Further, Co2+ and Co3+ ions occupy octahedral positions at larger dopant concentrations of CoO. From FTIR and Raman studies the coordination of germanium is changed from GeO4 to GeO6 with increase in the concentration of CoO. Dielectric parameters such as dielectric constant e′, loss tan δ, a.c. conductivity σac are increased and activation energy for a.c. conduction is decreased and hence opens the glass network with the increase of divalent cobalt ion concentration; which is also confirmed by decrease in glass transition temperature (Tg) and band gap energy (Eg). Density of defect energy states (EF) is explained with quantum mechanical tunneling (QMT) model.

Transparent glasses 40Sb2O3–20ZnF2–(40 − x)GeO2:xCuO, and 40Bi2O3–20ZnF2–(40 − y)GeO2:yCuO with x = 0, 0.6 and 0 ≤ y ≤ 1 wt% were prepared by melt quenching technique and were characterized by XRD and differential thermal analysis. Spectroscopic studies like optical absorption, FTIR, Raman, EPR and dielectric parameters (such as ɛ′, loss(tan δ), and σac) were carried out to examine the modifier and dopant effect on zinc germanate glass network. Optical absorption and EPR data have revealed that the environment of Cu2+ ions is more ionic in bismuth series rather than antimony glasses. Reduced bismuth ions have been found in pure and at lower concentration of dopant in Bi2O3 mixed glasses, which are useful for IR amplifications. FTIR and Raman spectra have indicated the conversion of GeO4 to GeO6 structural units by forming cross linking bonds like Bi–O–Ge, Ge–O–Cu, etc., and open the glass network with integration of Bi2O3 and CuO doping. It is also confirmed by decreasing Tg and Eg values. The temperature dependence of dielectric parameters at different frequencies was interpreted in terms of structural changes in the glass network.

Transparent glasses, melt quenching derived, containing 10RO·20Bi2O3·(70 − x)B2O3·xTiO2 [R = Ca, Sr] with x = 0, 0.5, 1.0 wt% were characterized by X-ray powder diffraction. Physical and spectroscopic properties viz., density, absorption, emission, electron paramagnetic resonance (EPR) and FTIR were investigated. The absorption band around 823 nm in pure glass samples is attributed to the electronic transition of 3P0 to 3P2 of Bi+ radicals. A small absorption hump centered around 609 nm is found in all doped glasses due to 2T2g to 2Eg transition of octahedral Ti3+ ions. The emission results revealed that all the samples exhibit a broad emission band covering entire visible-light range, with λex = 360 nm, centered 470–520 nm corresponds to electronic transition of 3P1 to 1S0 of Bi3+ ions, therefore the present materials can be potentially used as tunable or full-color display systems. And a strong emission around 706 nm with λex = 514 nm due to transition of 2P3/2 to 2P1/2 of Bi2+ ions. In SrO mixed glasses Ti4+ ions effect the environment of Bi3+ ion symmetry units from C2 to C3i. A small EPR signal (at room temperature) is observed in titanium doped glasses due to Ti3+ ions. In both the series with increase of TiO2 concentration BO4 units are gradually converted into BO3 units and new cross linkages are formed, like B–O–Ti, Bi–O–Ti at the expense of B–O–B bonds.

10MO·20Bi 2 O 3 ·(70− x )B 2 O 3 · x CuO [M=Pb, Zn] with x =0, 0.4 and 0.8 (wt%) glasses were synthesized by the melt-quenching technique and were characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. Physical parameters, like density, and spectroscopic studies (optical absorption, EPR, FTIR and photoluminescence) were used to understand the role of modifier oxide and CuO in the glass matrix. A red shift of the absorption band corresponds to 2 B 1g → 2 B 2g transition of Cu 2+ ions from P2 to Z4 samples and the increase of hyperfine splitting factor ( A ‖ ) from P2 to Z2 shows that with the integration of PbO by ZnO the electron density around copper ion is increased. It is also supported by the gradual increase in theoretical optical basicity values of ZnO mixed glasses, as compared to that of PbO mixed glass matrix. Reduced bismuth radicals are found in undoped and 0.4% CuO doped glasses of both the series. Analysis of the absorption and emission studies indicates that the concentration of luminescence centers of bismuth ions (Bi 3+ ions in UV region) is decreased by the integration of ZnO as well as by increasing the dopant concentration. In lead series PbO 4 and BiO 3 units are increased from P2 to P4 and in zinc series BiO 3 units are decreased from Z0 to Z4. The conductivity of the glass matrices is increased in both the series with the dopant of CuO.

Melt quenching derived (in air) transparent glasses containing 30LiF 10SrO (60 − x )B 2 O 3 x V 2 O 5 , with 0 ⩽ x ⩽ 1.0 (mol%) were investigated for physical, spectroscopic measurements, viz., optical absorption, electron spin resonance (ESR) and FTIR along with dielectric properties (dielectric constant e ′, loss tan δ , conductivity σ ac, etc.). The results were analyzed to correlate with each other in the light of local environment and oxidation states of vanadyl ion in the glass network. The observed blue shift in 3 T 1g (F) → 3 T 2g (F) and red shift in 2 B 2g → 2 E g transitions and decrease in Δ g ∥ /Δ g ⊥ values up to V 8 indicates that the decrease in tetragonality of the vanadium site. The increase in area of optical absorption peak, ESR signal intensity and in the relative value of ac conductivity up to 0.8 mol% of V 2 O 5 doped glasses is due to the predominant presence of V 4+ and V 3+ ions. Beyond this concentration, the redox ratio V 4+ /V 5+ is found to decrease. By the gradual replacement of B 2 O 3 by V 2 O 5 up to 0.8 mol% the semi conducting nature of the glass network is found to increase due to increase of BO 3 structural units beyond this concentration insulating strength of glass matrix is increased.

Transparent glasses of the composition 10RO.20Bi 2 O 3 .(70 − x) B 2 O 3 .xCuO [R = Ca, Ba] with x = 0, 0.4, 0.8 (wt.%) were prepared via melt-quenching technique and characterized using X-ray powder diffraction. Spectroscopic measurements, viz., optical absorption, EPR, FTIR and photoluminescence (PL) were studied at room temperature. Analysis of the present investigations indicates that the concentration of luminescence centers of bismuth ions (Bi 2+ ions in visible region) decreased by the integration of BaO and also by increasing dopent concentration. It is also observed that addition of CuO decreases stability of the glass network in calcium series and strengthens in barium series.

The alternate pathway of signal transduction via hydrolysis of phosphatidylcholine, the major cellular phospholipid, has been investigated in murine peritoneal macrophages. A sustained formation of diacylglycerol, is preceded by an enhanced production of phosphatidic acid, when the macrophages were given a stimulus with 12-O-tetradecanoyl phorbol-13-acetate for sixty minutes. Production of choline and choline metabolites are significantly increased too. Propranolol, which inhibits phosphatidate phosphohydrolase, the enzyme responsible for conversion of phosphatidic acid to diacylglycerol, can effectively block the formation of diacylglycerol. Inhibition of protein kinase C either by its inhibitors, staurosporine and H-7 or by depletion, apparently affect the generation of the lipid products. Moreover, based on the results of transphosphatidylation reaction, involvement of a phospholipase D in the phosphatidylcholine-hydrolytic pathway in macrophages is predicted. These observations support the view that probably the phorbol ester acting directly on protein kinase C of the macrophages activate their phosphatidylcholine-specific phospholipase D to allow a steady generation of second messengers, to enable them to participate in the cell signalling process in a more efficient manner than those generated in the phosphoinositide pathway of signal transduction.

Superoxide dismutase (SOD), a metal containing enzyme is present in parasite Leishmania donovani as well as in host macrophages both resident and activated in a detectable amount, although the level is much higher in the latter case. It is observed that at any particular protein concentration, the SOD activity is highest in the case of parasite infected macrophages and lowest in the case of normal resident macrophages; the SOD activity of thioglycolate activated macrophages lies in between the two. It is also noticed that formalin-killed Leishmania donovani neither attach to macrophages nor do they increase the SOD activity of the host. Thus, the processes, e.g. attachment of the parasite to the host membrane, subsequent membrane perturbation and thus activation of membrane bound enzyme NADPH oxidase leading to respiratory burst, may be responsible for an enormous increase in the SOD level in macrophages during infection. Moreover, the chemical nature of the SOD found in infected macrophages has been investigated by using an inhibitor, e.g. NaCN, which specifically inhibits Cu-Zn SOD but not Fe-SOD. A considerable inhibition of SOD activity by NaCN in infected macrophages confirms the chemical nature of the increased SOD to be of Cu-Zn type, usually found in host. Presumably, Cu-Zn SOD or host SOD plays a protective role at the time of parasite infection although the role of parasitic SOD or some other mechanisms for the survival of the parasite within the toxic phagolysosome environment, of the macrophage cannot be ruled out.

During an attempt to explore the mechanism of cobalt and vitamin B 12 effect on the peroxidase and tyrosine iodinase activity, it was observed that cobalt and not vitamin B 12 in vivo elicits a high plasma titer of a humoral factor, erythropoietin, which caused increased 59 Fe incorporation into red blood corpuscles. This erythropoietin was extracted from plasma or kidney and partially purified. This partially purified erythropoietin preparation when injected into starved rat caused increased 59 Fe incorporation into red blood corpuscles. The potency of the partially purified erythropoietin preparation from plasma and kidney was compared. This partially purified erythropoietin, as well as sheep step-I erythropoietin, when administered to mice gave rise to a response almost similar to cobalt administration. It appears that the effect of cobalt on the peroxidase or tyrosine iodinase activity might be mediated through the elevation of the erythropoietin titer of plasma. Moreover, this erythropoietin was found to stimulate both peroxidase and tyrosine iodinase activity of the enzyme preparation of submaxillary gland in experiments in vitro. Erythropoietin, purified further in our laboratory, also produced the same effect. Neuraminidase-treated erythropoietin, in contrast, failed to execute any such stimulatory effect on the iodination of tyrosine.

A modified procedure for the purification of E. coli galactose-1-phosphate uridyl transferase (E.C. 2.7.6.12) was developed which reproducibly gives pure enzyme. The purified enzyme was shown to be a dimeric protein with a subunit molecular weight of 41,000 and its amino acid composition and content of free sulfhydryl groups were determined. The N-terminal and C-terminal amino acid sequences were found to be NH2-thr-gln-phe-asn-pro-val-asp and -ser(val leu)-ala-COOH respectively. This N-terminal sequence allowed the identification of the start of the transferase gene in the DNA sequence determined by GRINDLEY. Furthermore it appears to define a nine base intercistronic region between the epimerase and transferase genes.

Total phospholipids were extracted from the heart, hepatopancreas, and hemolymph of the Indian horseshoe crab Carcinoscorpius rotundicauda by the conventional method. Characteristic group reaction and 2-dimensional thin-layer chromatography on silica gel were used for identification of different phospholipids. The phospholipid profile obtained from hemolymph and 2 major organs are comparable and show phosphatidyl choline (PC) and phosphatidyl ethanolamine to be the major phospholipids. A phospholipid has been consistently detected migrating immediately below the PC in the thin-layer chromatogram of lipids extracted from the hepatopancreas. When mixed methyl esters of this slower moving PC are resolved on a silica gel plate ran in hexane ether:acetic acid 80:20:1, with appropriate controls, an additional spot is seen just below the normal methyl ester, indicating a difference between the fatty acid compositions of 2 PC (e.g., regular and slower). The slower mixed methyl esters were found to comprise mainly the 4 saturated fatty acids: lauric, myristic, palmitic, and stearic. The slow moving PC seems to consist mainly of molecular species with the above-mentioned saturated fatty acids at both Sn 1 and Sn 2 positions.

Tissue slices of sheep kidney medulla catalyzed the incorporation of 14C-phenylalanine into protein when they were incubated in presence of twenty naturally occurring amino acids. Cobalt salt stimulated the incorporation significantly. Although slices from cortical or juxtaglomerular region of kidney catalyzed the incorporation of radioamino acid into proteins, yet no such stimulation of incorporation by cobalt salt was observed in those cases. The radioamino acid incorporated protein, produced under the influence of kidney medullary tissues in presence or absence of cobalt salt, was identified to be erythropoietin by its thermal stability, electrophoretic mobility on polyacrylamide gel and finally precipitation reaction with antierythropoietin.