cssi/SciSciGPT-SciSciNet huggingface dataset:
The Receptor Activator of Nuclear Factor-κB Ligand Inhibitor Osteoprotegerin Is a Bone-Protective Agent in a Rat Model of Chronic Renal Insufficiency and Hyperparathyroidism

Osteoprotegerin (OPG) acts by neutralizing the receptor activator of nuclear factor-κB ligand (RANKL), the primary mediator of osteoclast differentiation, function, and survival. We examined whether OPG could affect the bone loss associated with chronic kidney disease (CKD) in a rodent model of CKD and secondary hyperparathyroidism (SHPT). SHPT was induced in rats by 5/6 nephrectomy (5/6 Nx) and a 1.2% P/0.6% Ca2+ diet. Starting 1 week after 5/6 Nx, rats were treated with vehicle (veh) or OPG-Fc (3 mg/kg, intravenously) every 2 weeks for 9 weeks. At baseline, 3, 6, and 9 weeks, blood was taken and bone mineral density (BMD) and bone mineral content (BMC) were assessed by dual-energy X-ray absorptiometry. Serum parathyroid hormone (sPTH) levels reached 912 pg/ml in 5/6 Nx rats vs. 97 pg/ml in shams at 9 weeks. OPG-Fc had no effect on sPTH or Ca2+ levels throughout the 9-week study, indicating that SHPT was a renal effect independent of bone changes. At 3 weeks, 5/6 Nx-veh rats had osteopenia compared with sham-veh rats and 5/6 Nx-OPG-Fc rats had significantly higher percent changes in whole-body BMC, leg BMD, and lumbar BMD versus 5/6 Nx-veh rats. By 6–9 weeks, elevated sPTH was associated with reversal of bone loss and osteitis fibrosa in the proximal tibial metaphysis. OPG-Fc decreased this sPTH-driven high bone turnover, resulting in augmented thickness of proximal tibial trabeculae in 5/6 Nx rats. Thus, RANKL inhibition with OPG-Fc can block the deleterious effects of continuously elevated sPTH on bone, suggesting that RANKL may be an important therapeutic target for protecting bone in patients with CKD and SHPT.
Case report: lethal fetal head injury and placental abruption in a pregnant trauma patient

Fetal trauma in blunt abdominal trauma is uncommon, but traumatic fetal head injury is almost universally fatal to the fetus. Placental abruption is the most common injury to the gravid uterus in trauma, and when the mother survives, it is the most common cause of fetal death. The imaging diagnosis of these conditions may be difficult since there are only three cases reported in the literature of intrauterine skull fractures on plain films [3, 8, 10], ultrasound is in sensitive in the diagnosis of placental abruption [24], and the most sensitive test to diagnose placental abruption is external fetal monitoring with devices that measure uterine tone and contractility and fetal heart rate [23]. The diagnosis of fetal trauma and placental abruption may be made on contrast enhanced CT performed through the abdomen and pelvis of pregnant trauma patients. For these reasons, it is useful for the radiologist interpreting the CT scan to recognize fetal head injuries and placental abruption in pregnant trauma patients.Fig. 7 Axial scans through the bony pelvis demonstrate an unstable pelvic fracture with posterior pelvic ring disruption.There is a zone 2 fracture of the left sacrum and a fracture of the left obturator ring (arrowheads)
Progressive failure of cerebral angiogenesis supporting neural plasticity in aging rats

Previous work has demonstrated substantial formation of new synapses and capillary branches in visual cortex of young rats provided with complex experience. Synaptogenesis appears greatly weakened in old rats, however, perhaps because of an age-associated impairment of metabolic support. We have examined capillaries in visual cortex from eight 14-month-old and nine 24-month-old rats that had been kept for 50 days in either a complex environment with toys and other rats or in the standard laboratory condition they had been raised in. In spite of tissue expansion that increased cortical thickness and spread apart existing blood vessels in 14-month-old rats that received complex experience, the density of capillaries was not affected. These results indicate that new capillaries infiltrated the expanding tissue. These rats also had significantly more small-diameter capillaries, possibly reflecting the immaturity of new vessels and effectively reducing the maximum amount of blood available to the tissue. Similar but nonsignificant trends were observed in the 24-month-old animals given complex experience. These results suggest that angiogenesis, while it does occur, is substantially impaired in middle-aged animals, and a failure of angiogenesis in old rats may explain their reduced capacity for synaptogenesis.
Sporadic hypoglycemia: abnormal epinephrine response to the ketogenic diet or to insulin.

A controlled study of 5 patients with sporadic hypoglycemia, who fulfill the criteriafor ketotic hypoglycemia, demonstrated a deficiency in urinary excretion of epinephrine in response to hypoglycemia resulting from either the infusion of insulin or the administration of a ketogenic diet. It is suggested that "ketotic" hypoglycemia and sporadic hypoglycemia associated with inadequate epinephrine secretion may be the same disease.
A simple method for elution of IgA deposits from the skin of patients with dermatitis herpetiformis

To better understand the role of autoimmunity in the pathogenesis of dermatitis herpetiformis, linear IgA bullous dermatosis or other skin disorders, the antigenic specificity of the immune reactants bound in vivo in the skin must be identified. In order to do so, one must first be able to elute these immune reactants from the skin. We describe here a simple method of eluting not only specifically bound IgG, but also IgA and other immunoglobulins and complement components from skin biopsy material. The method involves cutaneous washing of the entrapped serum proteins in PBS pH 7 and pH 5 buffers followed by specific immunoglobulin elutions at pH 3 and 2. The IgA deposits which could not be removed by this treatment were eluted by a combination of low pH (0.5 M citrate pH 2) and a chaotropic agent (2 M NaCl). The relative concentration of IgA in eluates when quantitated by fluoroimmunoassay were three-to five-fold higher in dermatitis herpetiformis skin biopsy specimens, than in eluates of bullous pemphigoid or normal skin biopsy specimens.
The pectoralis major myocutaneous flap in head and neck reconstruction

This paper discusses the pectoralis major myocutaneous flap, its anatomy, preparation, and dissection, for use in head and neck reconstruction. Illustrative cases are reviewed and the advantages of this flap presented.
Outcome prediction after surgery and chemoradiation of squamous cell carcinoma in the oral cavity, oropharynx, and hypopharynx: use of baseline perfusion CT microcirculatory parameters vs. tumor volume.

Purpose To assess whether pretreatment perfusion computed tomography (PCT) may predict outcome in chemoradiated patients with oral cavity, oropharynx, and hypopharynx squamous cell carcinoma (SCCA) after surgical excision. Materials and Methods Twenty-one patients with SCCA were examined before treatment. The primary site was oral cavity in 6, oropharynx in 7, and hypopharynx in 8 patients; there were 11 T2, 6 T3, and 4 T4 tumors. PCT was performed at the level of largest tumor diameter based on standard neck CT. The data were processed to obtain blood flow (BF), blood volume (BV), mean transit time (MTT), and permeability surface area product (PS). Regions of interest were free-hand positioned on the lesions to obtain PCT measurements. Tumor volume was also calculated. Follow-up was performed with positron emission tomography (PET)/CT and endoscopy. Pearson correlation coefficient was used for comparison between the subgroups. A regression model was constructed to predict recurrence based on the following predictors: age, gender, tumor (T) and nodal (N) stage, tumor volume, and PCT parameters. Results BF mean , BF max , BV mean , BV max , MTT mean , PS mean , and PS max were significantly different between patients with and without tumor recurrence (0.0001, p max , BV max , MTT mean , and radiation dose ( p p = 0.00001, relative risk [RR] 7.4), low PS mean ( p = 0.0001, RR 14.3), and low BF max ( p = 0.002, RR 5.9). Conclusions Our data suggest that PCT parameters have a prognostic role in patients with SCCA.
Fabrication of 4, 5, or 6-fold symmetric 3D photonic structures using single beam and single reflective optical element based holographic lithography

Here we present the holographic fabrication of large area 3D photonic structures using a single reflective optical element (ROE) with a single beam, single exposure process. The ROE consists of a 3D printed plastic support that houses 4, 5, or 6-fold symmetrically arranged reflecting surfaces which redirect a central beam into multiple side beams in an umbrella configuration to be used in multi-beam holography. With a circular polarized beam incident to silicon wafer reflecting surfaces at the Brewster angle, multiple linearly s-polarized side beams are generated. 3D photonic crystal structures of woodpile, Penrose quasi-crystal, and hexagonal symmetry were produced with ROEs that have 4+1, 5+1 and 6+1 beam configurations, respectively. Since the ROE design can be readily changed and implemented for different photonic crystal structures, this fabrication method is more versatile and cost effective than currently comparable single optical methods like prisms and phase masks.
Electronic composition-property relationship applied to SO2 chemisorption on Pt111 surfaces, alloys, and overlayers.

We have developed a new electronic composition−property relationship between the adsorption energy of molecules binding unequally to multiple atoms on metal surfaces and the electronic properties of the surface. This relationship allows the estimation of the relative stability of adsorbates on various surfaces, assuming that the adsorbate adopts the same local configuration on each surface, and therefore also allows the estimation of the adsorption energy of molecules through large regions of parameter space in alloy systems with data from only a few explicit calculations. We have applied this relationship to the adsorption of SO2 on Pt surfaces alloyed with Pd, Cu, Ru, and Ni. Using a new formula for weighting the metal d-band, we found a strong linear relationship between the weighted positions of the d states of surfaces and the most stable molecular adsorption energies. The consequences of our electronic composition−property relationship for catalyst design are also discussed.
Is the incidence of fetal-to-maternal hemorrhage increased in patients with third-trimester bleeding?

Abstract Objective: If a pregnancy is complicated by third-trimester bleeding, is there a higher risk of fetal-to-maternal hemorrhage that might necessitate the administration of additional anti-D immune globulin to prevent alloimmunization in the patient who is Rh D-negative? The study objective was to analyze prospectively the incidence of fetal-to-maternal hemorrhage in pregnancies that were complicated by third trimester bleeding compared with three control groups. Study Design: Pregnancies that were complicated by third-trimester bleeding, preterm premature rupture of the membranes, and preterm labor were identified prospectively on admission. A group of preterm patients with no complications was also collected prospectively. Patients with any history and/or clinical evidence of trauma were excluded. Kleihauer-Betke tests were performed with all patients, and the results were blinded until study completion. Sample size calculations were performed to determine the minimum number of cases needed in each group. Results: A total of 403 patients were collected during the study period: 91 patients had third-trimester bleeding, 101 patients had preterm premature rupture of the membranes, 116 patients had preterm labor, and 95 patients were in the no complication group. There was no statistical difference identified in the Kleihauer-Betke test results between any of the study groups. Conclusion: The incidence of fetal-to-maternal hemorrhage does not appear to be increased in pregnancies that are complicated by third-trimester bleeding when compared to noncomplicated control subjects or to other obstetrically complicated pregnancies. This information would suggest that the routine administration of additional anti-D immune globulin (beyond the current recommended protocol) to women who are Rh D-negative whose pregnancies are complicated by third-trimester bleeding is not indicated. (Am J Obstet Gynecol 2003;188:1615-21.)
Flexibility and Commitment in International Conflicts

Flexibility and commitment in statecraft offer juxtaposed advantages and drawbacks, and the relative merits of these alternative stances have been an issue for several theorists of international politics. Yet the flexibility-commitment dilemma is seldom immediately relevant to the actual conduct of diplomacy in international conflicts. Statesmen tend to be inflexible. They cling to a particular policy through the conviction—often false—that the policy is appropriate for the international problem they face and/or through domestic pressures which forbid alternative policies. And statesmen also experience problems in realizing the theoretical benefits of commitment as a result of striving for objectives which are incompatible with the adversary's tolerances, experiencing difficulties in signaling commitments effectively, and/or facing conflicting preferences among their domestic colleagues. So from the statesman's position of “unapparent inflexibility,” the problems of achieving some flexibility within tightly constrained policies and signaling viable commitments effectively are both more pressing concerns than the relative merits of flexibility and commitment. And if academic research related to the flexibility-commitment issue is to be pertinent to the statesman, it must focus on this pair of issues.
Low temperature dynamic mapping reveals unexpected order and disorder in troponin

Troponin is a pivotal regulatory protein that binds Ca2+ reversibly to act as the muscle contraction on-off switch. To understand troponin function, the dynamic behavior of the Ca2+-saturated cardiac troponin core domain was mapped in detail at 10 °C, using H/D exchange-mass spectrometry. The low temperature conditions of the present study greatly enhanced the dynamic map compared with previous work. Approximately 70% of assessable peptide bond hydrogens were protected from exchange sufficiently for dynamic measurement. This allowed the first characterization by this method of many regions of regulatory importance. Most of the TnI COOH terminus was protected from H/D exchange, implying an intrinsically folded structure. This region is critical to the troponin inhibitory function and has been implicated in thin filament activation. Other new findings include unprotected behavior, suggesting high mobility, for the residues linking the two domains of TnC, as well as for the inhibitory peptide residues preceding the TnI switch helix. These data indicate that, in solution, the regulatory subdomain of cardiac troponin is mobile relative to the remainder of troponin. Relatively dynamic properties were observed for the interacting TnI switch helix and TnC NH2-domain, contrasting with stable, highly protected properties for the interacting TnI helix 1 and TnC COOH-domain. Overall, exchange protection via protein folding was relatively weak or for a majority of peptide bond hydrogens. Several regions of TnT and TnI were unfolded even at low temperature, suggesting intrinsic disorder. Finally, change in temperature prominently altered local folding stability, suggesting that troponin is an unusually mobile protein under physiological conditions.
Use of a locking reconstruction bone plate/screw system for mandibular surgery

Abstract Purpose: This study examined the use of a locking reconstruction bone plate/screw system for use in mandibular surgery. Patients and Methods: All patients treated with a locking reconstruction bone plate/screw system for fractures of the mandible or continuity defects in an 18-month period were prospectively studied. Ease of use of the locking plate/screw system, characteristics of the fractures/defects, and complications were tabulated. Results: One hundred two locking bone plates were placed in 84 patients. Most patients (n = 75) were treated for fractures of the mandible; there were eight continuity defects and one case of mandibular narrowing. There were no cases of malocclusion or difficulties encountered in using the plate/screw system. Loss of fixation was encountered in only one patient. Conclusions: The use of a locking plate/screw system was found to be simple, and it offers advantages over conventional bone plates by not requiring the plate to be compressed to the bone to provide stability.
Antigenicity and native structure of globular proteins: low frequency of peptide reactive antibodies

Recent reports that peptides can frequently mimic epitopes on globular proteins are inconsistent with early studies demonstrating that antibodies to native globular proteins generally do not bind peptides. This discrepancy could result from current confusion of two different populations of antibodies in antisera: one reacting with peptides and denatured protein and the other reacting only with the native protein. To test this possibility, several hundred monoclonal antibodies to rat cytochrome c were examined by ELISA for binding the intact protein and cyanogen bromide-cleaved peptides. Inhibition by soluble native cytochrome c identified which antibodies were specific for the native protein. The vast majority of these antibodies did not bind the peptides, whereas most of the antibodies specific for denatured forms did bind them. The results are consistent with the idea that antibodies to denatured antigen are readily detected in solid-phase assays, where some antigen molecules denature as they attach to microtiter plates, and show that these antibodies are generally the ones that react with peptides. Thus, reevaluation of data suggesting that anti-native globular protein antibodies bind peptides is warranted.
The Effect of the Meridional Circulation on the Baroclinic Instability of the Winter Zonal Flow

Abstract The linear instability of the observed winter zonal mean flow, with and without the inclusion of the meridional circulation, is presented. The purpose of this note is to determine whether the meridional circulation has an important effect on the growth-rate spectrum and structure of the linear baroclinic waves. It is found that the inclusion of the meridional circulation produced only slight changes in the growth-rate spectrum, as compared to the case where the meridional flow is neglected. The presence of the meridional flow destabilized all wavenumbers greater than 5, although the change was less than 7% for all wavenumbers. The maximum growth rate, with or without considering meridional circulation, occurred between wavenumbers 12 and 15. The wave structures were also very similar in the two cases. The maximum amplitude of the geopotential perturbation for wavenumbers 5–7 remains at the earth’s surface when the meridional circulation is included; however, the position of the maximum geopotenti...
Estimation of continuous solar spectral distributions from discrete filter measurements

Abstract Techniques exist for estimating a well-behaved continuous function given a relatively small number of carefully chosen samples of that function. Two of these methods are applied to the problem of obtaining a low-resolution spectral distribution of direct solar radiation from a few filter samples. The minimum variance estimation and cubic spline fitting techniques are different approaches which yield integrated irradiances within one percent of each other and the test spectrum. They both produce reasonable averaged spectra over most of the spectral interval tested.
Studies in genetically modified mice suggest novel mechanisms of mood regulation.

The field of biological psychiatry has been hindered by the paucity of animal models of depression and bipolar disorder that are reliable across laboratories, assess constructs with relevance to core symptomatology of these disorders, and include inducing conditions that are based on solid theoretical rationales about the etiologies of these disorders. Two papers published in this issue of Biological Psychiatry used molecular genetic techniques in rodents to reveal previously unidentified mechanisms involved in the neurobiological regulation of mood and affect, moving beyond the traditional targets of current pharmacotherapies. These papers suggest roles for γ-aminobutyric acid (GABA) A receptor and Circadian Locomotor Output Cycles Kaput (CLOCK) transcription factor in depression and bipolar disorder. Since malfunctions in such regulatory mechanisms lead to affective symptoms of depression and mania, these findings provide new insights regarding the etiology of mood dysregulation and its potential treatment.
MRI Measurements of Breast Tumor Volume Predict Response to Neoadjuvant Chemotherapy and Recurrence-Free Survival

OBJECTIVE. The purpose of this study was to assess the value of MRI measurements of breast tumor size for predicting recurrence-free survival (RFS) in patients undergoing neoadjuvant (preoperative) chemotherapy and to compare the predictive value of MRI with that of established prognostic indicators.SUBJECTS AND METHODS. The study included 62 patients undergoing neoadjuvant chemotherapy. The longest diameter and volume of each tumor were measured on MRI before and after one and four cycles of treatment. Change in diameter on clinical examination, tumor size at pathology, and the number of positive nodes were determined. Each measure of tumor extent was assessed for the ability to predict RFS.RESULTS. Univariate Cox analysis showed initial MRI volume was the strongest predictor of RFS (p = 0.002). Final change in MRI volume (p = 0.015) was more predictive than change in diameter on MRI (p = 0.077) or clinical examination (p = 0.27). Initial diameter on MRI (p = 0.003) and clinical examination (p = 0.033), ...
Fly ash‐amended compost as a manure for agricultural crops

Abstract Homemade organic compost prepared from lawn grass clippings was amended with fine fly ash collected from a coal‐fired power plant (SRS 484‐D, Savannah River Site, Aiken, SC) to investigate its usefulness as a manure in enhancing nutrient uptake and increasing dry matter yield in selected agricultural crops. Three treatments were compared: five crops (mustard, collard, string beans, bell pepper, and eggplant) were each grown on three kinds of soil: soil alone, soil amended with composted grass clippings, and soil amended with the mixed compost of grass clippings and 20% fly ash. The fly ash‐amended compost was found to be effective in enhancing the dry matter yield of collard greens and mustard greens by 378% and 348%, respectively, but string beans, bell pepper, and eggplant did not show any significant increase in dry matter yield. Analysis of the above‐ground biomass of these last three plants showed they assimilated high levels of boron, which is phytotoxic; and this may be the reason for thei...
Acute basophilic leukemia in a child: Anaphylactoid reaction and coagulopathy secondary to vincristine-mediated degranulation

Background. Acute de novo basophilic leukemia (ABL) is uncommon in adults, and extremely rare in children. To the authors' knowledge, there have been no previous reports of anaphylactoid reactions from basophilic degranulation in children with this condition. Methods. This report describes the clinicopathologic profile and complications of a patient with de novo ABL. Results. Immediately after the first induction dose of intravenous vincristine, the patient developed an anaphylactoid reaction and disseminated intravascular coagulation with massive pulmonary hemorrhage. A normal serum tryptase level suggested that this life-threatening event was secondary to tumor lysis (basophilic degranulation), rather than to a mast-cell mediated anaphylactic reaction to vincristine. This interpretation is supported by the coagulation studies, which suggested release of heparin from the blast granules. Conclusions. Although de novo ABL is rare, it should be considered when cytoplasmic basophilic granules are seen in the leukemic cells of patients with what otherwise appears to be undifferentiated leukemia, and the pertinent diagnostic procedures should be undertaken. During the treatment of ABL, potential complications related to basophilic degranulation should be anticipated, and antihistamine prophylaxis may be of value.
Experimental Study of the Reaction between Vinyl and Methyl Radicals in the Gas Phase. Temperature and Pressure Dependence of Overall Rate Constants and Product Yields

The vinyl−methyl cross-radical reaction was studied by laser photolysis/photoionization mass spectroscopy. Overall rate constants and quantitative product yields were obtained in direct real-time experiments in the temperature region 300−900 K and bath gas (He) density (3−12) × 1016 molecules cm-3. The observed overall C2H3 + CH3 rate constant is independent of pressure and demonstrates a slight negative temperature dependence, which can be represented by the expression k4 = 5.1 × 10-7T-1.26 exp(−362/T) molecule-1 cm3 s-1 (The expression has ±10% uncertainty, see text for details.). Propene, acetylene, and allyl radicals were identified as primary products of the C2H3 + CH3 reaction. At room temperature propene and acetylene are the major products of the reaction, whereas at 900 K production of allyl radicals becomes the dominating channel. On the basis of these experimental results, a mechanism consisting of two major routes is proposed. One route proceeds via direct abstraction of a hydrogen atom from t...
A hybrid approach to urban land use/cover mapping using Landsat 7 Enhanced Thematic Mapper Plus (ETM+) images

A hybrid method that incorporates the advantages of supervised and unsupervised approaches as well as hard and soft classifications was proposed for mapping the land use/cover of the Atlanta metropolitan area using Landsat 7 Enhanced Thematic Mapper Plus (ETM+) data. The unsupervised ISODATA clustering method was initially used to segment the image into a large number of clusters of pixels. With reference to ground data based on 1 : 40 000 colour infrared aerial photographs in the form of Digital Orthophoto Quarter Quadrangle (DOQQ), homogeneous clusters were labelled. Clusters that could not be labelled because of mixed pixels were clipped out and subjected to a supervised fuzzy classification. A final land use/cover map was obtained by a union overlay of the two partial land use/cover maps. This map was evaluated by comparing with maps produced using unsupervised ISODATA clustering, supervised fuzzy and supervised maximum likelihood classification methods. It was found that the hybrid approach was sligh...
Microglia and neuroprotection: implications for Alzheimer's disease

The first part of this paper summarizes some of the key observations from experimental work in animals that support a role of microglia as neuroprotective cells after acute neuronal injury. These studies point towards an important role of neuronal-microglial crosstalk in the facilitation of neuroprotection. Conceptually, injured neurons are thought to generate rescue signals that trigger microglial activation and, in turn, activated microglia produce trophic or other factors that help damaged neurons recover from injury. Against this background, the second part of this paper summarizes recent work from postmortem studies conducted in humans that have revealed the occurrence of senescent, or dystrophic, microglial cells in the aged and Alzheimer's disease brain. These findings suggest that microglial cells become increasingly dysfunctional with advancing age and that a loss of microglial cell function may involve a loss of neuroprotective properties that could contribute to the development of aging-related neurodegeneration.
Endothelin-1 is a transcriptional target of p53 in epidermal keratinocytes and regulates ultraviolet-induced melanocyte homeostasis.

Keratinocytes contribute to melanocyte activity by influencing their microenvironment, in part, through secretion of paracrine factors. Here, we discovered that p53 directly regulates Edn1 expression in epidermal keratinocytes and controls UV-induced melanocyte homeostasis. Selective ablation of endothelin-1 (EDN1) in murine epidermis (EDN1(ep-/-) ) does not alter melanocyte homeostasis in newborn skin but decreases dermal melanocytes in adult skin. Results showed that keratinocytic EDN1 in a non-cell autonomous manner controls melanocyte proliferation, migration, DNA damage, and apoptosis after ultraviolet B (UVB) irradiation. Expression of other keratinocyte-derived paracrine factors did not compensate for the loss of EDN1. Topical treatment with EDN1 receptor (EDNRB) antagonist BQ788 abrogated UV-induced melanocyte activation and recapitulated the phenotype seen in EDN1(ep-/-) mice. Altogether, the present studies establish an essential role of EDN1 in epidermal keratinocytes to mediate UV-induced melanocyte homeostasis in vivo.
Identification, sequence, and expression of the gene encoding the second-largest subunit of the vaccinia virus DNA-dependent RNA polymerase.

Abstract The gene, rpo 132, encoding the second-largest subunit of the vaccinia virus DNA-dependent RNA polymerase was identified and sequenced. Two complementary approaches, involving antiserum to purified vaccinia virus RNA polymerase, were used to locate the rpo132 gene. One method involved the screening of a λgtl1 library of vaccinia virus genome fragments and the other was based on the immunoprecipitation and polyacrylamide gel electrophoresis of the in vitro translation products of mRNA that hybridized to immobilized vaccinia virus DNA. The deduced open reading frame of the rpo 132 gene predicted a polypeptide of 1164 amino acid residues with sequence similarities to the second-largest RNA polymerase subunits of eubacteria, archaebacteria, and eukaryotes as well as to other poxviruses. Transcriptional analyses indicated that rpo132 has both early and late RNA start sites and is expressed throughout infection.
Ultrasensitive analysis of binding affinity of HIV receptor and neutralizing antibodies using solution-phase electrochemiluminescence assay

Abstract Binding of a few ligand molecules with its receptors on cell surface can initiate cellular signaling transduction pathways, and trigger viral infection of host cells. HIV-1 infects host T-cells by binding its viral envelope protein (gp120) with its receptor (a glycoprotein, CD4) on T cells. Primary strategies to prevent and treat HIV infection is to develop therapies (e.g., neutralizing antibodies) that can block specific binding of CD4 with gp120. The infection often leads to the lower counts of CD4 cells, which makes it an effective biomarker to monitor the AIDS progression and treatment. Despite research over decades, quantitative assays for effective measurements of binding affinities of protein–protein (ligand–receptor, antigen–antibody) interactions remains highly sought. Solid-phase electrochemiluminescence (ECL) immunoassay has been commonly used to capture analytes from the solution for analysis, which involves immobilization of antibody on solid surfaces (micron-sized beads), but it cannot quantitatively measure binding affinities of molecular interactions. In this study, we have developed solution-phase ECL assay with a wide dynamic range (0–2 nM) and high sensitivity and specificity for quantitative analysis of CD4 at femtomolar level and their binding affinity with gp120 and monoclonal antibodies (MABs). We found that binding affinities of CD4 with gp120 and MAB (Q4120) are 9.5 × 10 8 and 1.2 × 10 9 M −1 , respectively. The results also show that MAB (Q4120) of CD4 can completely block the binding of gp120 with CD4, while MAB (17b) of gp120 can only partially block their interaction. This study demonstrates that the solution-phase ECL assay can be used for ultrasensitive and quantitative analysis of binding affinities of protein–protein interactions in solution for better understating of protein functions and identification of effective therapies to block their interactions.
Cytosolic and Mitochondrial Malic Enzyme Isoforms Differentially Control Insulin Secretion

In islet beta-cells and INS-1 cells both the high activity of malic enzyme and the correlation of insulin secretion rates with pyruvate carboxylase (PC) flux suggest that a pyruvate-malate cycle is functionally relevant to insulin secretion. Expression of the malic enzyme isoforms in INS-1 cells and rat islets was measured, and small interfering RNA was used to selectively reduce isoform mRNA expression in INS-1 cells to evaluate its impact on insulin secretion. The cytosolic NADP(+)-specific isoform (ME1) was the most abundant, with the mitochondrial isoforms NAD(+)-preferred (ME2) expressed at approximately 50%, and the NADP(+)-specific (ME3) at approximately 10% compared with ME1. Selective reduction (89 +/- 2%) of cytosolic ME1 mRNA expression and enzyme activity significantly reduced glucose (15 mM:41 +/- 6%, p < 0.01) and amino acid (4 mM glutamine +/- 10 mM leucine: 39 +/- 6%, p < 0.01)-stimulated insulin secretion. Selective small interfering RNA reduction (51 +/- 6%) of mitochondrial ME2 mRNA expression did not impact glucose-induced insulin secretion, but decreased amino acid-stimulated insulin secretion by 25 +/- 4% (p < 0.01). Modeling of the metabolism of [U-(13)C]glucose by its isotopic distribution in glutamate indicates a second pool of pyruvate distinct from glycolytically derived pyruvate in INS-1 cells. ME1 knockdown decreased flux of both pools of pyruvate through PC. In contrast, ME2 knockdown affected only PC flux of the pyruvate derived from glutamate metabolism. These results suggest a physiological basis for two metabolically and functionally distinct pyruvate cycles. The cycling of pyruvate by ME1 generates cytosolic NADPH, whereas mitochondrial ME2 responds to elevated amino acids and serves to supply sufficient pyruvate for increased Krebs cycle flux when glucose is limiting.
Photometric calibrations of the AFP-675 far-ultraviolet cameras experiment

The far ultraviolet cameras experiment (NRL-803), part of the U.S. Air Force Space Test Program's AFP-675 payload, flew aboard the space shuttle Discovery in April - May 1991 (STS-39). While in orbit, the experiment gathered data about sources of far-ultraviolet radiation in near-Earth and distant space. To obtain quantitative information from the data, pre-flight and post-flight calibrations of the flight instruments were required. Calibrations were performed using a vacuum-UV optical collimator and two types of light sources: (a) a vacuum-UV monochromator, whose output wavelength could be varied over the wavelength range 105 - 200 nm; and (b) gas discharge tubes with interference-filter windows, giving monochromatic output at selected wavelengths within this range. Calibrations were of two types (the first performed only before flight): (a) using the far UV cameras as photodiodes; and (b) using the cameras to record images on film, as during flight. In addition, in-flight calibrations are obtained from observations of hot stars or other sources which have been measured by previous space experiments. Results from the calibrations are used to derive absolute far-UV brightnesses of objects from the actual flight data.
Preventing youthful disconnectedness

Abstract Using data from the National Longitudinal Survey of Youth, this article examines the characteristics (and later life histories) of 16- to 23-year-olds who, during the 1980s, were “disconnected” from mainstream society, that is, they were not enrolled in school, not gainfully employed, not in the military, and not married to someone who was “connected” in one of these ways. One in three youths were disconnected for at least half of a calendar year. As adults, youths who were disconnected for a short time (in only one or two years) did not differ substantially from those who were never disconnected in terms of educational attainment, work history, family income, reliance on government programs, and marital status. However, those who were disconnected in three or more years experienced significantly greater hardships. This article suggests that school-related interventions (such as career-oriented education, after-school “safe havens,” and targeting individual deficits) might help prevent youthful disconnectedness.
Stability of the breakoff point in a high‐speed cell sorter

Background High-speed jet-in-air cytometric sorting requires knowledge of the time it takes a particle to travel from the laser to the point where the jet breaks into droplets. Variations in this breakoff time will result in poorer yields and poorer sort purities. Methods This work examined the physical mechanisms that lead to the break up of the jet into droplets and calculated the stability of the droplet breakoff time relative to physical parameters, which govern the behavior of the jet. Results We derived the variations in the breakoff time and found that small variations in the drive frequency, temperature, pressure, and drive amplitude can lead to correspondingly large changes in the breakoff time. We found explicitly that the time it takes the jet to break up is not necessarily correlated with the distance to the breakoff point. Conclusions Many high-speed cell sorters use active means to control the breakoff time. A common method to monitor the breakoff time is to visually monitor the breakoff point. This technique in fact may decrease the sorting purity and efficiency by inadvertently correcting for breakoff time variations. We show explicitly the breakoff time's dependence on a number of physical parameters that can be monitored to increase the stability of the breakoff time. Cytometry Part A 56A:63–70, 2003. © 2003 Wiley-Liss, Inc.
Molecular layer deposition of poly(p-phenylene terephthalamide) films using terephthaloyl chloride and p-phenylenediamine.

Ultrathin polymer films can be fabricated using the gas-phase method known as molecular layer deposition. This process typically uses bifunctional monomers in a sequential, self-limiting reaction sequence to grow conformal polymer films with molecular layer control. In this study, terephthaloyl chloride (TC) and p-phenylenediamine (PD) were used as the bifunctional monomers to deposit poly(p-phenylene terephthalamide) (PPTA) thin films. 3-Aminopropyl trimethoxysilane or ethanolamine was used to prepare amine-terminated surfaces prior to the PPTA MLD. The surface chemistry and growth rate during PPTA MLD at 145 °C were studied using in situ transmission Fourier transform infrared (FTIR) spectroscopy experiments on high surface area powders of SiO2 particles. PPTA MLD thin film growth at 145 °C was also examined using in situ transmission FTIR experiments on flat KBr substrates with an amine-terminated Al2O3 ALD overlayer. The integrated absorbances of the N−H and amide I stretching vibrations were measured...
A Cell Programmable Assay (CPA) chip.

This article describes two kinds of “Cell Programmable Assay” (CPA) chips that utilize passive pumping for the culture and autonomous staining of cells to simply common protocols. One is a single timer channel CPA (sCPA) chip that has one timer channel and one main channel containing a cell culture chamber. The sCPA is used to culture and stain cells using Hoechst nuclear staining dye (a 2 step staining process). The other is a dual timer channel CPA (dCPA) chip that has two timer channels and one main channel with a chamber for cell culture. The dCPA is used here to culture, fix, permeablize, and stain cells using DAPI. The additional timer channel of the dCPA chip allows for automation of 3 steps. The CPA chips were successfully evaluated using HEK 293 cells. In addition, we provide a simplified equation for tuning or redesigning CPA chips to meet the needs of a variety of protocols that may require different timings. The equation is easy to use as it only depends upon the dimensions of microchannel and the volume of the reagent drops. The sCPA and dCPA chips can be readily modified to apply to a wide variety of common cell culture methods and procedures.
Mechanistic models for the activation volume and rate sensitivity in metals with nanocrystalline grains and nano-scale twins

Abstract This paper describes mechanistic models that seek to rationalize experimentally determined low values for the activation volume associated with the high strain rate sensitivity of nanocrystalline metals. We present models for the emission of partial or perfect dislocations from stress concentrations at a grain boundary or twin boundary. The emission of deformation twins is likewise examined as a competing mechanism to perfect dislocation emission. The approach illustrates the important roles of both the intrinsic stacking fault energy and the unstable stacking energy. We find that the models lead to estimates of activation volumes in the range 3 − 10 b 3 for truly nanocrystalline metals. Activation volumes are found to increase monotonically with increasing grain size. The findings are found to be in accord with available experimental evidence in both a quantitative and qualitative manner. Deficiencies in the available experimental evidence are noted, specifically in the context of explaining some of the difficulties in comparing theoretical predictions to experimental observation.
Overexpression of the transgene for manganese superoxide dismutase (MnSOD) in 32D cl 3 cells prevents apoptosis induction by TNF-α, IL-3 withdrawal, and ionizing radiation

Abstract Objective. Stabilization of the mitochondria in IL-3-dependent hematopoietic progenitor cell line 32D cl 3 by overexpression of the transgene for manganese superoxide dismutase (MnSOD) prior to ionizing radiation prevents apoptosis. We now demonstrate that overexpression of the MnSOD transgene also protects 32D cl 3 cells from apoptosis caused by exposure to tumor necrosis factor-α (TNF-α) or withdrawal of interleukin (IL)-3. Materials and Methods. The hematopoietic progenitor cell line, 32D cl 3, and subclones overexpressing the human MnSOD transgene, 1F2 or 2C6, were radiated to 1000 cGy or were exposed to TNF-α (0 to 100 ηg/mL) or were subjected to IL-3 withdrawal. The cells were then examined at several time points for DNA strand breaks using a comet assay, depolarization of the mitochondrial membrane, activation of caspase-3, PARP cleavage, and apoptosis, and also for changes in cell cycle distribution. Results. Overexpression of the transgene for MnSOD resulted in increased survival following exposure to radiation, exposure to TNF-α, or IL-3 withdrawal. The cell lines overexpressing MnSOD (1F2 or 2C6) displayed decreased radiation-induced, TNF-α-induced, orIL-3 withdrawal–induced mitochondrial membrane permeability, caspase-3 and PARP activation, and apoptosis. Conclusions. Overexpression of the human MnSOD transgene in 32D cl 3 cells results in stabilization of the mitochondria and reduction in radiation-, TNF-α-, or IL-3 withdrawal–induced damage. Thus, MnSOD stabilization of the mitochondrial membrane is relevant to reduction of apoptosis by several classes of oxidative stress inducers.
Pressure Blades and Total Cutting Edge: An Experiment in Lithic Technology

Pressure techniques were used to remove 83 blades from a preformed obsidian core weighing 820 grams, yielding 17.32 meters of acute cutting edge. The blades represented 91 percent of the original weight (2.1 centimeters of acute cutting edge per gram of original material), thus demonstrating the efficiency of the pressure-blade techniques for the production of acute cutting edges.
Shiga toxin producing E coli bloodstream infection secondary to Strongyloides penetration through intestinal mucosa

A 51-year-old woman with diabetes, who immigrated to the USA 22 years ago from Laos, was admitted to the hospital for evaluation of fever, abdominal pain, vomiting and diarrhoea. A workup for acute gastroenteritis revealed a positive stool PCR for Shiga toxin-producing Escherichia coli. Two sets of blood cultures drawn at admission were positive for E coli. A review of her previous medical records revealed the presence of eosinophilia, up to 20%, 14 years prior to that was never investigated. Therefore, stool samples were examined and two of three specimens were positive for Strongyloides stercoralis larvae, confirming the diagnosis of Strongyloides hyperinfection syndrome.
MeV polyatomic ion beams from a dynamitron accelerator for desorption mass spectrometry studies

Abstract This paper describes a modified duoplasmatron ion source coupled to a Dynamitron accelerator as a convenient source of MeV polyatomic ions. The modification provides low fluxes of polyatomic ion beams which are utilized in single-particle counting techniques such as desorption mass spectrometry studies. A variety of polyatomic ions, including C 2 + , C 3 + , CH + , CH 3 + , C 3 H 3 + , C 4 H 9 + , C 7 H 15 + , CO + , O 2 + , CO 2 + , CF + , CF 3 + , C 3 F 5 + and C 4 F 7 + , have been produced and accelerated over an energy range of 800 keV to 3.9 MeV. An application of incident polyatomic ions in desorption mass spectrometry experiments is presented, and it is shown that MeV polyatomic ions are an attractive alternative to atomic ions for desorption mass spectrometry studies.
Radiogenic Os in primitive basalts from the northwestern U.S.A.: Implications for petrogenesis

Abstract Chemically primitive late Cenozoic tholeiitic basalts from the northwestern U.S.A. have Os-isotopic compositions more radiogenic than observed for most basalts from the ocean basins. This result is inconsistent with the simple petrogenetic model that explains the geographically correlated Sr-, Nd- and Pb-isotopic variation in these basalts as resulting solety from melting of metasomatized lithospheric mantle peridotite of varying age across this area. A magma source composed of a mixture of peridotite and pyroxenite/eclogite also fails because at the high percentage of mafic component required to explain the observed Nd—Os isotope systematics, this mixed source would not produce melts that match the major- and trace-element compositions of the observed olivine tholeiites. A more likely explanation for the observed isotopic compositions involves interaction of sublithospheric primary melts that are similar in composition to mid-ocean ridge basalt (MORB) with high-187Os/188Os materials in the lower crust or lithospheric mantle. Though not uniquely defined, mass-balance calculations suggest that the lithospheric component is mafic-potassic in composition, possibly a small-volume melt of mafic material in the lower crust or upper mantle. If the radiogenic Os is attributable to such interaction, the isotopic compositions of the tholeiites can be satisfied by 2–25% addition of the lithospheric component to a primitive MORB parental magma. These results show that the Os-isotope system in continental basalts can provide a clear distinction between magmas derived by melting isotopically evolved peridotitic lithosphere and those produced from a sublithospheric primary melt contaminated by mafic material in the lithosphere.