The Surface Morphology of Mitogen-Stimulated Human Peripheral Blood Lymphocytes

The changes occurring in surface morphology during the transformation of normal peripheral blood lymphocytes by phytohaemagglutinin (PHA) are described and the surface ultrastructure of the PHA-induced blasts is compared with that of pokeweed mitogen (PWM)-and rabbit anti-beta2-microglobulin antiserum-induced blasts. Both mitogen-specific and non-specific changes were observed and their possible relationship to the activation of lymphocyte subpopulations is discussed. Similar surface characteristics found in various tissue lymphoid cells are also described.     

Investigating the Behavior of Waste Alumina Powder and Nylon Fibers for Eco-Friendly Production of Self-Compacting Concrete

Self-compacting concrete (SCC) incorporating secondary raw materials has been extensively used around the globe due to its improved fresh, mechanical and durability properties. This study was planned to evaluate the suitability of locally available waste alumina powder (AP) and nylon textile fibers (NF) as a partial replacement for fine and coarse aggregates with the ultimate goal to locally produce SCC with desired properties. The used AP was acquired from a local market and NF was collected from a local textile factory. Various dosages of AP (10%, 20%, 30%, 40% and 50% by volume of fine aggregates) and NF (1% and 2% by volume of coarse aggregates) were studied. Tests including slump flow, V-funnel and J-ring tests were performed for examining the fresh properties of developed SCC. Results showed that the addition of AP has an insignificant effect on the superplasticizer dosage for maintaining a constant flow of 70 cm. However, a higher dosage of superplasticizer was required for a mixture with increasing dosages of NF to sustain a constant flow. Similarly, slump flow time (for a spread of 50 cm) and V-funnel time increased for mixtures with higher dosages of AP and NF. Tested SCC mixtures incorporating 40% and 50% of AP with 1% and 2% of NF showed an extreme blocking assessment due to their increased interparticle friction, the higher water absorption capacity of used AP and NF leading to increased flow resistance and hence, showed lower passing ability. The compressive strength was 16% higher for specimens incorporating 40% of AP due to the filling effect of AP which fills the micro-pores, leading to a more dense and compact internal micro-structure, confirmed through scanning electron microscopy analysis. An ultrasonic pulse velocity test conducted on hardened specimens verified the findings of the compressive strength results. Moreover, it was observed that NF has an insignificant effect on the compressive strength; however, flexural strength was increased due to the incorporation of NF, especially at higher dosages of AP.     

Differences Between Lymphocytes of Leukemic and Non-Leukemic Patients with Respect to Morphologic Features, Motility, and Sensitivity to Guinea Pig Serum

Observations were made on viable lymphocytes in 22 specimens of bloodfrom 20 patients to test whether leukemic lymphocytes have distinctive characteristics. Special slide-chambers were used in this study. The features suggestive of leukemic lymphocytes were: large chromatin masses, prominentnucleoli, abnormal size of cells, flagella-like structures, reduced motility, andan increase in the sensitivity to inactivated guinea pig sera. An index summarizing these abnormal features selected correctly 9 blood specimens from 7 patients with chronic lymphocytic or lymphosarcoma-cell leukemia. Distinctiveabnormalities of the living lymphocytes were not found in the blood of 3 patients who were diagnosed lymphosarcoma and had normal lymphocyte countsand some lymphosarcoma-cell lymphocytes in stained blood films. Bloodlymphocytes from 8 patients with infectious mononucleosis, diabetes, hemochromatosis, and other diseases were correctly identified as non-leukemic. Thefindings obtained in this study indicate that viable leukemic lymphocytes arecharacterized by abnormal morphologic features, reduced motility, and increased sensitivity to heat-inactivated guinea pig sera.

Submitted on June 23, 1961 Accepted on August 4, 1961     

Assessment of a Bionic Broach Implanted with Nylon Fibers

The optimization of a broach surface is of great significance to improve the cutting performance of the tool. However, the traditional optimization method (surface texture, coating, etc.) destroys the stress distribution of the tool and reduces the service life of the tool. To avoid these problems, four kinds of flocking surfaces (FB1, FB2, FB3, and FB4), imitating the biological structure of Daphniphyllum calycinum Benth (DCB), were fabricated on the rake face of the broach by electrostatic flocking. The broaching experiment, wettability, and spreading experiment were then conducted. Moreover, the mathematical model of the friction coefficient of the bionic broach was built. The effect of broaches with different flocking surfaces on the broaching force, chip morphology, and surface quality of workpieces was studied. The results indicate that the flocked broaches (FB) with good lubricity and capacity of microchips removal (CMR) present a smaller cutting force (F_c) and positive pressure (F_t) compared to the unflocked broach (NB), and reduce the friction coefficient (COF). The chip curl was decreased, and the shear angle was increased by FB, which were attributed to the function of absorbing lubricant, storing, and sweeping microchips. Its vibration suppression effect enhanced the stability in the broaching process and improved the surface quality of the workpiece. More importantly, the FB2 with the most reasonable fluff area and spacing exhibited the best cutting performance. The experimental conclusions and methods of this paper can provide a new research idea for functional structure tools.     

Surface Immunoglobulin of Human Lymphocytes

Using ferritin as surface marker, the localization of the surface immunoglobulin (Ig) was studied on peripheral lymphocytes from normal human individuals and patients with macroglobulinaemia Waldenström by scanning immunoelectron microscopy. Normal IgG-, IgM-lymphocytes and pathological IgM-lymphocytes were then compared with regard to their topographical differences. In all cells examined, IgG- and IgM-conjugated ferritin particles were detected all over the cell surface, but the distribution of the former on the normal IgG-lymphocytes was slightly more diffuse than that of the latter on the normal and pathological IgM-lymphocytes. Furthermore, in the pathological IgM-lymphocytes, the clustered IgM-conjugated ferritin particles were found in great number on the microvilli. Normal IgG-lymphocytes were almost always characterized by short rod-like microvilli standing densely and vertically on the cell surface. Some of normal IgM-lymphocytes had a similar appearance to those of normal IgG-lymphocytes (type A) but others (type B) had tilted rod-like microvilli or wide plate-like processes on their surface. As for IgM-lymphocytes of macroglobulinaemia, most lymphocytes had tilted rod-like microvilli and wide plate-like processes similar to type B, whereas a minor population of the pathological lymphocytes carried long, thin rod-like microvilli standing vertically on the surface.     

Surface Morphology,Compressive Behavior,and Energy Absorption of Graded Triply Periodic Minimal Surface 316L Steel Cellular Structures Fabricated by Laser Powder Bed Fusion

Laser powder bed fusion (LPBF) is an emerging technique for the fabrication of triply periodic minimal surface (TPMS) structures in metals. In this work, different TPMS structures such as Diamond, Gyroid, Primitive, Neovius, and Fisher–Koch S with graded relative densities are fabricated from 316L steel using LPBF. The graded TPMS samples are subjected to sandblasting to improve the surface finish before mechanical testing. Quasi-static compression tests are performed to study the deformation behavior and energy absorption capacity of TPMS structures. The results reveal superior stiffness and energy absorption capabilities for the graded TPMS samples compared to the uniform TPMS structures. The Fisher–Koch S and Primitive samples show higher strength whereas the Fisher–Koch S and Neovius samples exhibit higher elastic modulus. The Neovius type structure shows the highest energy absorption up to 50% strain among all the TPMS structures. The Gibson–Ashby coefficients are calculated for the TPMS structures, and it is found that the C₂ values are in the range suggested by Gibson and Ashby while C₁ values differ from the proposed range.     

Cell Surface and Enzyme Markers of Cord Blood Lymphocytes

Summary. Human cord blood (CB) lymphocytes were studied with several markers for T- and B-cells and the results compared with those of adult peripheral blood (PB) samples. The proportion of E-rosettes was significantly lower in CB (mean 24.7±13.5 SD) than in PB (67.5 ± 7.3 SD). Treatment with neuramidase produced a marked increase in the proportion of E-rosettes in CB (mean 47±13.9 SD), still below the PB values. The proportion of CB lymphocytes showing block positivity with α-naphthyl-acetate-esterase correlated closely with the percentage of E-rosettes in neuraminidase treated cells. The percentage of H-rosettes (human RBC) was significantly higher in CB (7.2±6.0) than in PB (3.2±1.6 SD). Re-rosetting experiments showed that in CB about 30% of the E-positive cells formed H-rosettes, in contrast to 5% in PB. These findings indicate that in CB the real number of T-lymphocytes is higher than shown by conventional E-rosette formation.
The proportion of B-lymphocytes, tested by surface immunoglobulins and by rosette formation with mouse RBC (M-rosettes), was similar in CB and in adult PB. A slight increase in cells with IgM on the surface was found in CB. The overall proportion of lymphocytes with negative B and T markers in CB is three times greater than in adult PB. Levels of the enzyme terminal deoxynucleotidyl transferase were marginally increased in CB; in two out of 41 samples the levels were above those found in normal bone marrow. CB may be a suitable model for the study of lymphocyte subsets with negative B and T markers in man.     

Surface Morphology of Human Leukocytes

Surface morphology of individual leukocytes was correlated with their lightmicroscopic appearance by a simple, direct technique. Circulating leukocytes ofall types were roughened spheres withdiameters similar to red cells, and leukocyte types could not be distinguishedconsistently by surface morphology.After surface contact, leukocytes increased in diameter and exhibited a variety of projections. Cells spread onsurfaces could be identified by externalmorphology. Several stages in the phagocytosis of latex particles were demonstrated. The study of surface contoursby scanning electron microscopy represents a new approach to morphology.

Submitted on April 27, 1970 Revised on June 22, 1970 Accepted on July 23, 1970     

Human Chronic Lymphocytic Leukaemia Surface Markers and Activation of Lymphocytes

Cell surface markers and the responses of lymphocytes to T- and B-cell mitogens were studied in 10 patients with CLL. T cells were identified as cells rosetting with sheep red blood cells (SRBC), and S-Ig was used as a marker for B lymphocytes. Most cells from all patients had detectable amounts of S-Ig, and the percentage of cells rosetting with SRBC was low in all cases. Of the lymphocytes from these patients, 3–74 % (mean 33 %) were positive for the acid esterase (ANAE), which has been claimed to be a T-cell marker. However, some patients had cells that were positive for both S-Ig and ANAE. Acid esterase staining is therefore not a valid T-cell marker in chronic lymphocytic leukaemia. In cultures containing the T-cell mitogen leucoagglutinin (LA) and the T- and B-cell mitogen pokeweed mitogen (PWM) the reactivity of the lymphocytes was low. The cells responded vigorously to the T- and B-cell mitogen protein A (PA); however, the response was serum-dependent, being strong in a culture medium containing foetal calf serum (FCS), but impaired in the presence of human AB serum. Only 1 patient had cells that responded to the B-cell mitogen LPS.     

Surface Immunoglobulins of Circulating Lymphocytes in Mouse Plasmacytoma. II. The Influence of Plasmacytoma RNA on Surface Immunoglobulins of Lymphocytes

Circulating lymphocytes of plasmacytoma-carrying BALB/c mice werefound to lose their normal surface immunoglobulins; in their place surfacestructures characteristic of the specific plasmacytoma globulin were demonstrated by the immunocytoadhesiontechnique. These changes were experimentally reproduced by the incubation of normal BALB/c lymphocyteswith an RNA preparation obtained byhot phenol extraction from the excisedplasmacytomas. RNA treated byRNAse was inactive, while DNAse ortrypsin had no inactivating effect.Lymphocytes, killed with heat or KCN,underwent no alteration of surfacereceptors following incubation with thetumor RNA. Plasmacytoma RNA, injected intraperitoneally into normalmice, also altered the reactivity of circulating lymphocytes. These observations suggest the possibility that thiseffect contributes to the functionalimpairment of the immune system inthis disease.

Submitted on August 16, 1971 Accepted on October 18, 1971     

Preparation,Surface and Pore Structure of High Surface Area Activated Carbon Fibers from Bamboo by Steam Activation

High surface area activated carbon fibers (ACF) have been prepared from bamboo by steam activation after liquefaction and curing. The influences of activation temperature on the microstructure, surface area and porosity were investigated. The results showed that ACF from bamboo at 850 °C have the maximum iodine and methylene blue adsorption values. Aside from the graphitic carbon, phenolic and carbonyl groups were the predominant functions on the surface of activated carbon fiber from bamboo. The prepared ACF from bamboo were found to be mainly type I of isotherm, but the mesoporosity presented an increasing trend after 700 °C. The surface area and micropore volume of samples, which were determined by application of the Brunauer-Emmett-Teller (BET) and t-plot methods, were as high as 2024 m²/g and 0.569 cm³/g, respectively. It was also found that the higher activation temperature produced the more ordered microcrystalline structure of ACF from bamboo.     

Cell Surface Galactosyltransferase and Lectin Agglutination of Thymus and Spleen Lymphocytes

Lectin agglutination and cell surface galactosyltransferase (EC 2.4.1.67; 1-O-alpha-D-galactosyl-myo-inositol:raffinose galactosyltransferase) enzyme activity have been studied with thymus and spleen lymphocytes of neonatal rats. Thymus lymphocytes were more agglutinable by concanavalin A than by wheat germ agglutinin, whereas spleen lymphocytes were more agglutinable by wheat germ agglutinin than by concanavalin A. Thymus lymphocytes, but not spleen lymphocytes, of neonatal rats could be blast transformed by concanavalin A. Cell surface galactosyltransferase activity was present on both types of lymphocytes, but was greatly increased on thymus cells after blast transformation. The differences in lectin agglutination suggest a difference in the surface membranes of thymus and spleen lymphocytes. The increase in cell surface galactosyltransferase activity with blast transformation of thymus lymphocytes may be related to the exteriorization of the Golgi apparatus into the plasma membrane.     

Surface Immunoglobulins on Lymphocytes in Chronic Lymphocytic Leukaemia and Lymphosarcoma

S ummary . The density of surface immunoglobulins on peripheral blood lymphocytes from 10 patients with chronic lymphocytic leukaemia (CLL) and three patients with lymphosarcoma was examined using a sandwich radio-immunolabelling technique. In healthy people two populations of lymphocytes are seen: densely labelled cells with a high surface immunoglobulin density or B cells and lightly labelled T cells. CLL lymphocytes were found to comprise a single population with labelling characteristics of B lymphocytes in eight patients and of T lymphocytes in two patients. In the three lymphosarcoma patients grain count histograms revealed two or three populations where the abnormal lymphocytes fell into the T cell type in two and into the B cell group in one patient. There were no essential clinical differences between these three patients.     

The Unique Surface Molecules on Intestinal Intraepithelial Lymphocytes: From Tethering to Recognizing

Interspersed among epithelial cells (ECs), intraepithelial lymphocytes (IELs) might be important constituents of the physiological and immunological barriers of the intestinal epithelial layer. IELs are composed of memory-effector T cell subtypes bearing the T cell receptor-γδ (TCRγδ) and TCRαβ. The intimate cell adhesion molecules- and tight junction proteins-mediated biological interactions between IELs and ECs ensure that IELs can reside within the intraepithelial compartment and survey large areas of the villus epithelium. As sentinels in this critical interface, IELs express TCRs that recognize antigenic peptides presented by conventional major histocompatibility complex (MHC) molecules or by non-classical MHC molecules. Moreover, IELs monitor for stressed or damaged ECs to mediate pathological responses and maintain intestinal homeostasis. In this review, we address how IELs reside within the epithelium and exert their sentinel functions.     

Compressive Behavior of Fiber-Reinforced Concrete with End-Hooked Steel Fibers

In this paper, the compressive behavior of fiber-reinforced concrete with end-hooked steel fibers has been investigated through a uniaxial compression test in which the variables were concrete compressive strength, fiber volumetric ratio, and fiber aspect ratio (length to diameter). In order to minimize the effect of specimen size on fiber distribution, 48 cylinder specimens 150 mm in diameter and 300 mm in height were prepared and then subjected to uniaxial compression. From the test results, it was shown that steel fiber-reinforced concrete (SFRC) specimens exhibited ductile behavior after reaching their compressive strength. It was also shown that the strain at the compressive strength generally increased along with an increase in the fiber volumetric ratio and fiber aspect ratio, while the elastic modulus decreased. With consideration for the effect of steel fibers, a model for the stress–strain relationship of SFRC under compression is proposed here. Simple formulae to predict the strain at the compressive strength and the elastic modulus of SFRC were developed as well. The proposed model and formulae will be useful for realistic predictions of the structural behavior of SFRC members or structures.     

Mechanical,Microstructure and Surface Characterizations of Carbon Fibers Prepared from Cellulose after Liquefying and Curing

In this study, Cellulose-based carbon fibers (CBCFs) were prepared from cellulose after phenol liquefaction and curing. The characteristics and properties of CBCFs were examined by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). The results showed that, with increasing carbonization temperature, the L_a, L_c, and L_c/d₍₀₀₂₎ of CBCFs increased gradually, whereas the degree of disorder R decreased. The –OH, –CH₂–, –O–C– and phenyl group characteristic absorption peaks of CBCFs reduced gradually. The cross-linked structure of CBCFs was converted into a graphite structure with a six-ring carbon network during carbonization. The surface of CBCFs were mainly comprised of C–C, C–O, and C=O. The tensile strength, carbonization yield and carbon content of CBCFs obtained at 1000 °C were 1015 MPa, 52%, and 95.04%, respectively.     

Polypropylene/Short Glass Fibers Composites: Effects of Coupling Agents on Mechanical Properties,Thermal Behaviors,and Morphology

This study uses the melt compounding method to produce polypropylene (PP)/short glass fibers (SGF) composites. PP serves as matrix while SGF serves as reinforcement. Two coupling agents, maleic anhydride grafted polypropylene, (PP-g-MA) and maleic anhydride grafted styrene-ethylene-butylene-styrene block copolymer (SEBS-g-MA) are incorporated in the PP/SGF composites during the compounding process, in order to improve the interfacial adhesion and create diverse desired properties of the composites. According to the mechanical property evaluations, increasing PP-g-MA as a coupling agent provides the composites with higher tensile, flexural, and impact properties. In contrast, increasing SEBS-g-MA as a coupling agent provides the composites with decreasing tensile and flexural strengths, but also increasing impact strength. The DSC results indicate that using either PP-g-MA or SEBS-g-MA as the coupling agent increases the crystallization temperature. However, the melting temperature of PP barely changes. The spherulitic morphology results show that PP has a smaller spherulite size when it is processed with PP-g-MA or SEBS-g-MA as the coupling agent. The SEM results indicate that SGF is evenly distributed in PP matrices, but there are distinct voids between these two materials, indicating a poor interfacial adhesion. After PP-g-MA or SEBS-g-MA is incorporated, SGF can be encapsulated by PP, and the voids between them are fewer and indistinctive. This indicates that the coupling agents can effectively improve the interfacial compatibility between PP and SGF, and as a result improves the diverse properties of PP/SGF composites.     

SARS-CoV-2 Disinfection of Air and Surface Contamination by TiO2 Photocatalyst-Mediated Damage to Viral Morphology,RNA, and Protein

SARS-CoV-2 is the causative agent of COVID-19, which is a global pandemic. SARS-CoV-2 is transmitted rapidly via contaminated surfaces and aerosols, emphasizing the importance of environmental disinfection to block the spread of virus. Ultraviolet C radiation and chemical compounds are effective for SARS-CoV-2 disinfection, but can only be applied in the absence of humans due to their toxicities. Therefore, development of disinfectants that can be applied in working spaces without evacuating people is needed. Here we showed that TiO₂-mediated photocatalytic reaction inactivates SARS-CoV-2 in a time-dependent manner and decreases its infectivity by 99.9% after 20 min and 120 min of treatment in aerosol and liquid, respectively. The mechanistic effects of TiO₂ photocatalyst on SARS-CoV-2 virion included decreased total observed virion count, increased virion size, and reduced particle surface spike structure, as determined by transmission electron microscopy. Damage to viral proteins and genome was further confirmed by western blotting and RT-qPCR, respectively. The multi-antiviral effects of TiO₂-mediated photocatalytic reaction implies universal disinfection potential for different infectious agents. Notably, TiO₂ has no adverse effects on human health, and therefore, TiO₂-induced photocatalytic reaction is suitable for disinfection of SARS-CoV-2 and other emerging infectious disease-causing agents in human habitation.     

Idiotypic Specificity of Surface Immunoglobulin and the Maturation of Leukemic Bone-marrow-derived Lymphocytes

Certain cases of chronic lymphocytic leukemia are associated with monoclonal immunoglobulins in the serum. In the present study it was possible to demonstrate that the surface immunoglobulin of the leukemic lymphocytes was idiotypically identical to the serum monoclonal immunoglobulin of the same individual. This was done through the use of fluorescent antibodies that were prepared against the isolated immunoglobulin M kappa serum protein from patient Ei. Such antibodies, after absorption, failed to react with the lymphocytes of other individuals. Capping experiments indicated that both the immunoglobulin M and the immunoglobulin D on the leukemic cells possessed the same idiotypic specificity.A population of plasma cells was also identified in the peripheral blood of patient Ei that showed strong intracellular staining with the idiotypic antiserum and was the apparent source of the specific serum immunoglobulin. The accumulated evidence indicates that the plasma cells were derived from the leukemic lymphocytes by a process of differentiation. Surface immunoglobulin D disappeared and surface immunoglobulin M decreased markedly in this process.