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Scuffing or scoring is an important form of damage leading to component replacements in lubricated mechanical systems such as power drives, gears, bearings, cams and followers, piston rings etc. Since scuffing necessarily involves localized welding of asperities, suitable surface modifications or coating can impart a good resistance to scuffing. A new class of low temperature salt bath nitriding process provides good resistance to scuffing. The current work is on evaluation of the scuffing resistance of AISI 4340 steels imparted with two such treatments. Experimental investigations were conducted on Sursulf and Arcor treated AISI 4340 steel specimen using a pin on ring test system under boundary lubrication condition. Continuous monitoring of friction records and (near surface) bulk temperature were done under step loading. Limiting loads and load velocity relations were evaluated and using the data generated and a thermo-mechanical wear model, performance is indexed. Off line studies on surface finish, hardness variations and surface transformations were also accomplished. Some salient aspects of the investigation and data generated are presented here. Onset of scuffing was observed to be far delayed with pin specimen imparted with these treatments compared to hardening. [DOI: 10.1115/1.1504089]

Aims and Objectives: This study was conducted to compare the clinical assessment of impacted third molars of mandible with panaromic radiograph (OPG) and intraoral periapical radiograph (IOPA) and to assess the efficacy of IOPA and. Moreover, we corroborated the OPG and IOPA findings of impacted mandiblar third molar root apex to inferior alveolar canal. Materials and Methods: A total of 200 patients with pericoronitis were examined who were indicated for surgical extraction, among which 50 patients were selected for the study. All the patients underwent a radiographic survey with a digital OPG and IOPA of impacted mandibular third molars, along with clinical survey for anatomic relationship, type of impaction, space available, position in relation to second molar, number of roots, root curvature, and proximity of nerve canal. The data was subjected to statistical analysis. The Statistical Package for Social Sciences version 4.0.1 software was used for analyzing the collected data. Results: The study revealed that IOPA was more accurate in determining a majority of the factors affecting the third molar surgery, including relationship of the external oblique ridge (IOPA vs OPG = 96%:90%), anteroposterior relation with ramus (IOPA vs OPG = 70%:66%), vertical depth of impaction (IOPA vs OPG = 72%:68%), number of roots (P = 0.013), morphology of roots (IOPA vs OPG = 96%:90%); however, OPG was found to be accurate in evaluating the type of impaction (IOPA vs OPG = 88%:94%), canal relation, along with root of impacted molar (IOPA vs OPG = 74%:86%). Conclusion: To conclude, although IOPA has a marginal angle over OPG in assessing various parameters, only the number of roots have a greater accuracy (P < 0.0013) in IOPA than with OPG. However, the OPG is the better choice to be considered when the patient is associated with trismus. [ABSTRACT FROM AUTHOR]

A reply by M. Ramprasad to a letter to a editor about his article "Effect of Backpack Weight on Postural Angles in Preadolescent Children" in a 2010 issue is presented.

With an interest in monitoring the patency of stents that are used to treat strictures in the bile duct, this paper reports the investigation of a wireless sensing system to interrogate a microsensor integrated into the stent. The microsensor is comprised of a 28-μm-thick magnetoelastic foil with 8.25-mm length and 1-mm width. Magnetic biasing is provided by permanent magnets attached to the foil. These elements are incorporated into a customized 3D polymeric package. The system electromagnetically excites the magnetoelastic resonant sensor and measures the resulting signal. Through shifts in resonant frequency and quality factor, the sensor is intended to provide an early indication of sludge accumulation in the stent. This work focuses on challenges associated with sensor miniaturization and placement, wireless range, drive signal feedthrough, and clinical use. A swine specimen in vivo experiment is described. Following endoscopic implantation of the sensor enabled plastic stent into the bile duct, at a range of approximately 17 cm, the signal-to-noise ratio of ~10 6 was observed with an interrogation time of 336 s. These are the first reported signals from a passive wireless magnetoelastic sensor implanted in a live animal., (© 2024. The Author(s).)

Background: Deficiency in hip girdle neuromuscular control can cause exaggerated Dynamic Knee Valgus (DKV) which afflicts the knee joint and lead to knee injuries especially ACL injury in sports. Though Kinesio taping (KT) is known to improve function, stability and proprioception, the evidence is inconclusive on its effectiveness in athletes. We hypothesized that kinesio taping could enhance neuromuscular control of the hip girdle there by causing a reduction in DKV., Aim/objective: To determine whether KT on Gluteus medius can correct exaggerated dynamic knee valgus and improves hip abductor strength when compared to sham KT., Method: 40 collegiate level athletes, aged between 18 and 28 years, of both genders with presence of dynamic knee valgus (>8° for men and >13° for women) were recruited in the study. Athletes were excluded if they had history of lower back pain, history of any injury or surgery to the lower extremities during the past year. Subjects who met the inclusion criteria were randomized into kinesio taping (KT) group and sham taping (ST) group. The Drop Jump test and the Donnatelli Drop Leg Test (DDT) were performed before, and on the third day, immediately after the application of KT on them and documented., Results: There was a significant reduction in DKV among male [4.0° (95% CI 3.5-4.5); p < 0.001] and female [4.3° (95% CI 3.5-5.2); p < 0.002] immediately after application of taping but not on the third day after application of KT. There was a significant rise in DDT immediately and on the third day after application of KT between KT group and SC group., Conclusion: There was a reduction in DKV immediately after the application of KT. However, there was no significant difference between KT group and SC group on the third day. Meanwhile, gluteus medius strength also showed significant improvement immediately after taping and it was maintained even on the third day., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Thyroid disorders are common in pregnancy and the most common disorder is subclinical hypothyroidism. Due to the complex hormonal changes during pregnancy, it is important to remember that thyroxine requirements are higher in pregnancy. According to recent American Thyroid Association (ATA) guidelines, the recommended reference ranges for TSH are 0.1 to 2.5 mIU/L in the first trimester, 0.2 to 3.0 mIU/L in the second trimester, and 0.3 to 3.0 mIU/L in the third trimester. Maternal hypothyroidism is an easily treatable condition that has been associated with increased risk of low birth weight, fetal distress, and impaired neuropsychological development. Hyperthyroidism in pregnancy is less common as conception is a problem. Majority of them are due to Graves' disease, though gestational hyperthyroidism is to be excluded. Preferred drug is propylthiouracil (PTU) with the target to maintain free T4 in upper normal range. Doses can be reduced in third trimester due to the immune-suppressant effects of pregnancy. Early and effective treatment of thyroid disorder ensures a safe pregnancy with minimal maternal and neonatal complications.

We have previously identified a 94- to 97-kDa oxidized low density lipoprotein (LDL)-binding protein in mouse macrophages as macrosialin (MS), a member of the lamp family. Earlier immunostaining studies have shown that MS and its human homolog, CD68, are predominantly intracellular proteins. However, using sensitive techniques such as flow cytometry (FACS) and cell-surface-specific biotinylation, we now show that there is significant surface expression of these proteins. FACS analysis of intact cells using mAb FA/11 showed small but definite surface expression of MS in resident mouse peritoneal macrophages but this was greatly enhanced with thioglycollate elicitation. Biotinylation of intact cells and detergent-solubilized cell preparations followed by immunoprecipitation revealed 10-15% of the total MS content of elicited macrophages on the plasma membrane. Similar results were obtained with untreated RAW 264.7 cells. FACS analysis of intact THP-1 monocytic cells showed minimal surface expression of CD68 on unactivated cells (4% of total cell content). Stimulation with phorbol 12-myristate 13-acetate increased both surface and total CD68 expression considerably. Furthermore, the specific binding at 4 degrees C and uptake at 37 degrees C of 125I-labeled oxidized LDL by activated THP-1 cells was inhibited by 30-50% by CD68 mAbs KP-1 and EBM-11. Thus, although the surface expression of MS/CD68 at steady-state represents only a small percentage of their total cellular content, these proteins can play a significant role in oxidized LDL uptake by activated macrophages in vitro and could contribute to foam cell formation in atherosclerotic lesions.

An apolipoprotein (apo) E- and lipoprotein lipase-independent, high affinity, saturable and specific binding site and pathway for uptake of certain triglyceride-rich lipoproteins (TGRLP) by human monocyte-macrophages that leads to lipid accumulation and foam cell formation in vitro has been reported; two membrane binding activities were identified as receptor candidates with apparent molecular masses of 200 and 235 kDa [Gianturco et al. (1994) J. Lipid Res. 35, 1674-1687]. Here we present new evidence that these activities are TGRLP receptors with unique biochemical properties which distinguish them from other lipoprotein receptors. Protease and heparinase susceptibility studies demonstrate that (1) these activities have essential protein, but not heparan sulfate proteoglycan (HSPG) components; (2) the membrane binding proteins (MBPs) are located on the cell surface; (3) HSPGs do not facilitate TGRLP binding to this specific cellular site. Upon reduction, MBP 200 and 235 are both converted into a single, new binding activity of intermediate mobility (MBP 200R); all MBP forms displayed high affinity, saturable TGRLP binding with similar Kds (1.4-2.2 micrograms/mL). Notably, MBP 200R retained the combined ligand binding capacity of MBP 200 and 235 prior to reduction, demonstrating that, unlike members of the LDL receptor or the scavenger receptor families, disulfide bonds are not critical for activity. At 65 degrees C, MBP 235 was converted into MBP 200 without loss of total binding activity, suggesting heat dissociates a small subunit not required for binding from a common large protein subunit that binds TGRLP. Since the MBPs are found on the cell surface, are themselves functionally and structurally related, have distinctly different biochemical properties from members of the LDL receptor and scavenger receptor families, and share all critical characteristics with the cellular binding site, we hypothesize that they represent a new and unique receptor family for apoE- and lipoprotein lipase-independent uptake of TGRLP by human monocyte-macrophages.

Previously we reported that human blood-borne and THP-1 monocyte-macrophages have an apolipoprotein E- and lipoprotein lipase-independent, high affinity, specific binding site for the uptake and degradation of hypertriglyceridemic VLDL and plasma chylomicrons distinct from the LDL receptor gene family and the acetyl LDL receptor (Gianturco et al., J. Lipid Res. 35:1674-1687, 1994). Ligand blot analyses identified two cell-surface, structurally related membrane binding proteins as receptor candidates of M(r) approximately 200 kDa and M(r) approximately 235 kDa which are converted into a single ligand binding species of intermediate mobility upon reduction. We now report a approximately 1200-fold purification of the reduced candidate receptor protein from cultured THP-1 monocytes.

Autoimmune diseases are characterized by the presence of autoantibodies often restricted to host proteins exhibiting charge rich domains. Charged polypeptides elicit strong immune responses, and cationized bovine serum albumin and other cationic proteins are significantly more immunogenic than their less charged counterparts. These phenomena may involve enhanced protein uptake by macrophages, resulting in greater processing and presentation of antigenic peptide-MHC complexes to T-cells. We compared macrophage cell-surface binding and uptake of native and cationized bovine serum albumin. Specific binding of [125I]cationized bovine serum albumin to THP-1 macrophages in vitro was 11-16 fold greater than for native albumin. Half-maximal inhibition of [125I]cationized albumin binding was observed at 10-7M ligand. The specificity of [125I]cationized bovine serum albumin binding and uptake was further studied in terms of competitive inhibition of proteolysis by proteins of varying charge content. Cationized bovine serum albumin, but not native albumin, inhibited proteolysis of [125I]cBSA. Calf thymus histones also inhibited cBSA degradation. High concentration of myelin basic protein was moderately effective at blocking cBSA degradation, while myoglobin and beta lactalbumin showed no inhibition. These results indicate that specific cell-surface binding sites which occur on macrophages may mediate selective uptake of certain proteins with highly charged domains including some autoantigens.