Combined SERS/DFT studies of push-pull chromophore self-assembled monolayers: insights into their surface orientation.

Having clear and deep information on the surface/interface of deposited molecules is of crucial importance for the development of efficient optoelectronic devices. This paper reports on a joint experimental/theoretical hybrid approach based on Raman spectroscopy in order to provide information on the orientation of push-pull chromophores deposited onto a gold surface. In addition, several parameters can strongly control or impede the orientation of such molecules on the surface such as: the molecular structure, the surface itself, the method of deposition and the solvents used. From this approach, additional information has been highlighted such as perpendicularly depositing the molecule on the surface, the bithiophene compounds displaying more solvent effects compared to terthiophene molecules and so on. According to the results, the joint SERS/DFT study proves to be an effective tool for probing the arrangement of push-pull chromophores and selecting the right experimental conditions to tune the surface properties.

Percutaneous radiological gastrostomy: single-puncture double-anchor technique.

PURPOSE: We evaluated technical success, safety and effectiveness of percutaneous radiological gastrostomy (PRG) with a modified technique: single puncture and double anchor. MATERIALS AND METHODS: From January 2008 to June 2011, 163 patients underwent PRG with a single-puncture double-anchor technique. The stomach was punctured with a 17-gauge Chiba needle, and gastropexy was performed by placing two anchors in the gastric lumen. Finally, a 12-F Wills-Oglesby percutaneous gastrostomy catheter was inserted. Technical success and complications at 30 days were evaluated on the basis of imaging and patients' medical records. RESULTS: PRG was successfully completed in all 163 patients. Only a single puncture was required in all patients. The average PRG procedure time was 9 min. Three patients had major complications: haemorrhage (n=2) and pneumoperitoneum (n=1). Ten patients had minor complications: tube malfunction/breakage (n=9), and leakage through the insertion site (n=1). Two patients died 30 days after the procedure. CONCLUSIONS: Single-puncture double-anchor PRG is a fast, safe and effective technique.

A surface enhanced Raman spectroscopy study of aminothiophenol and aminothiophenol-C60 self-assembled monolayers: evolution of Raman modes with experimental parameters.

P-aminothiophenol (PATP) is a well-known molecule for the preparation of self-assembled monolayers on gold via its thiol functional group. After adsorption, it has been demonstrated that this molecule is anchored to gold through its thiol group, and standing nearly upright at the surface with the amino functional group on top. This molecule has been extensively studied by surface enhanced Raman spectroscopy but its exact SERS spectrum remains unclear. Here, we demonstrate that it can be strongly affected by at least two experimental parameters: laser power and layer density. Those features are discussed in terms of a dimerization of the PATP molecules. The free amino group affords the adsorption of other molecules such as C(60). In this case, a complex multilayer system is formed and the question of its precise characterisation remains a key point. In this article, we demonstrate that surface enhanced Raman spectroscopy combined with x ray photoelectron spectroscopy can bring very important information about the organization of such a self-assembled multilayer on gold. In our study, the strong evolution of Raman modes after C(60) adsorption suggests a change in the organization of aminothiophenol molecules during C(60) adsorption. These changes, also observed when the aminothiophenol layer is annealed in toluene, do not prevent the adsorption of C(60) molecules.

Surface enhanced Raman spectroscopy of organic molecules deposited on gold sputtered substrates.

Aggregates of Au nanoparticles have been extremely easily obtained on glass substrates by physical sputtering under primary vacuum. With such a protocol, we demonstrate that it is possible to control the surface plasmon band absorption. Surface enhanced Raman spectroscopy (SERS) experiments were performed with methylene blue, zinc octacarboxyphthalocyanine, 4-aminothiophenol and cysteamine. The correlation between the absorption band and the wavelength giving the highest SERS intensity is clearly observed for methylene blue, in accordance with the electromagnetic enhancement theory. For the other molecules, effects of the chemical enhancement are also observed. In addition, we noticed a strong influence of the nature of the adsorbed molecule on the enhancement factor for a given wavelength. The origin of this feature is discussed in terms of resonant effects or multipolar surface plasmon modes.

Forming Weakly Interacting Multilayers of Graphene Using Atomic Force Microscope Tip Scanning and Evidence of Competition between Inner and Outer Raman Scattering Processes Piloted by Structural Defects.

We report on an alternative route based on nanomechanical folding induced by an AFM tip to obtain weakly interacting multilayer graphene (wi-MLG) from a chemical vapor deposition (CVD)-grown single-layer graphene (SLG). The tip first cuts and then pushes and folds graphene during zigzag movements. The pushed graphene has been analyzed using various Raman microscopy plots- AD/ AG × EL4 vs ΓG, ω2D vs Γ2D, Γ2D vs ΓG, ω2D+/- vs Γ2D+/-, and A2D-/ A2D+ vs A2D/ AG. We show that the SLG in-plane properties are maintained under the folding process and that a few tens of graphene layers are stacked, with a limited number of structural defects. A blue shift of about 20 cm-1 of the 2D band is observed. The relative intensity of the 2D- and 2D+ bands have been related to structural defects, giving evidence of their role in the inner and outer processes at play close to the Dirac cone.

Anatomical and functional connections between the locus coeruleus and the nucleus tractus solitarius in neonatal rats.

This study was designed to investigate brain connections among chemosensitive areas in newborn rats. Rhodamine beads were injected unilaterally into the locus coeruleus (LC) or into the caudal part of the nucleus tractus solitarius (cNTS) in Sprague-Dawley rat pups (P7-P10). Rhodamine-labeled neurons were patched in brainstem slices to study their electrophysiological responses to hypercapnia and to determine if chemosensitive neurons are communicating between LC and cNTS regions. After 7-10 days, retrograde labeling was observed in numerous areas of the brainstem, including many chemosensitive regions, such as the contralateral LC, cNTS and medullary raphe. Whole-cell patch clamp was done in cNTS. In 4 of 5 retrogradely labeled cNTS neurons that projected to the LC, firing rate increased in response to hypercapnic acidosis (15% CO2), even in synaptic blockade medium (SNB) (high Mg(2+)/low Ca(2+)). In contrast, 2 of 3 retrogradely labeled LC neurons that projected to cNTS had reduced firing rate in response to hypercapnic acidosis, both in the presence and absence of SNB. Extensive anatomical connections among chemosensitive brainstem regions in newborn rats were found and at least for the LC and cNTS, the connections involve some CO2-sensitive neurons. Such anatomical and functional coupling suggests a complex central respiratory control network, such as seen in adult rats, is already largely present in neonatal rats by at least day P7-P10. Since the NTS and the LC play a major role in memory consolidation, our results may also contribute to the understanding of the development of memory consolidation.

An essential octamer motif in the mb-1 (Igalpha) promoter.

The mb-1 (Igalpha) gene is B cell-specific and expressed throughout B cell maturation. In combination with B29 (Igbeta) and surface immunoglobulin mb-1 comprises the B cell receptor complex (BCR). The murine mb-1 promoter has been characterized to depend on the trans-acting transcription factors; Sp1, ets, lkaros, and EBF for full promoter activity. These trans-acting factors are also involved in the regulation of mb-1's closely related heterodimeric partner, B29. However, octamer transcription factors 1 and 2 (Oct-1 and Oct-2) are also necessary for full B29 promoter activity while they are not known to be required for mb-1 promoter activity. Here, we show that the octamer transcription factors bind a degenerate octamer consensus sequence within the mb-1 promoter. Like B29, the mb-1 octamer-binding, motif interacted with both ubiquitously expressed Oct-1 and the B cell-specific Oct-2 transcription factors. Furthermore, the interaction of Oct-1 and Oct-2 contributed to the regulation of the mb-1 promoter as site-directed mutations within the octamer motif substantially reduced its activity. These data confirm that octamer factor interactions and function contribute to the full transcriptional activity of the mb-1 promoter.

A randomized comparison of two prophylaxis regimens and a paired comparison of on-demand and prophylaxis treatments in hemophilia A management.

BACKGROUND: Prophylaxis with factor (F)VIII is considered the optimal treatment for managing hemophilia A patients without inhibitors. OBJECTIVES: To compare the efficacy of two prophylaxis regimens (primary outcome) and of on-demand and prophylaxis treatments (secondary outcome), and to continue the evaluation of immunogenicity and overall safety of the ADVATE Antihemophilic Factor (Recombinant), Plasma/Albumin Free Method (rAHF-PFM). PATIENTS/METHODS: Previously on-demand-treated patients aged 7-59 years (n = 66) with FVIII levels ≤ 2% received 6 months of on-demand treatment and then were randomized to 12 months of either standard (20-40 IU kg(-1) every other day) or pharmacokinetic (PK)-tailored (20-80 IU kg(-1) every third day) prophylaxis, both regimens intended to maintain FVIII trough levels at or above 1%. Efficacy was evaluated in terms of annualized bleeding rates (ABRs). As subjects were first treated on-demand and then on prophylaxis, statistical comparisons between these treatments were paired. RESULTS: Twenty-two (33.3%) subjects on prophylaxis experienced no bleeding episodes, whereas none treated on-demand were free from an episode of bleeding. ABRs for the two prophylaxis regimens were comparable, whereas differences between on-demand and either prophylaxis were statistically significant (P < 0.0001): median (interquartile range [IQR]) ABRs were 43.9 (21.9), 1.0 (3.5), 2.0 (6.9) and 1.1 (4.9) during on-demand treatment, standard, PK-tailored and any prophylaxis, respectively. There were no differences in FVIII consumption or adverse event rates between prophylaxis regimens. No subject developed FVIII inhibitors. CONCLUSIONS: The present study demonstrates comparable safety and effectiveness for two prophylaxis regimens and that prophylaxis significantly reduces bleeding compared with on-demand treatment. PK-tailored prophylaxis offers an alternative to standard prophylaxis for the prevention of bleeding.

Comparative pharmacokinetics of plasma- and albumin-free recombinant factor VIII in children and adults: the influence of blood sampling schedule on observed age-related differences and implications for dose tailoring.

BACKGROUND: Dose tailoring of coagulation factors requires reliably estimated and reproducible pharmacokinetics (PK) in the individual patient. OBJECTIVES: To investigate the contribution of both biological and methodological factors to the observed variability of factor VIII (FVIII) PK, with the focus on differences between children and adults, and to examine the implications for dosing. PATIENTS: Data from 52 1-6-year-old and 100 10-65-year-old patients with hemophilia A (FVIII < or = 2 IU dL(-1)) in three clinical studies were included. RESULTS: In vivo recovery was lower, weight-adjusted clearance was higher and FVIII half-life was on average shorter in children than in adults. However, a reduced blood sampling schedule for children was estimated to account for up to one half of the total observed differences. Intrapatient variance in PK was smaller than interpatient variance in 10-65-year-olds. Age and ratio of actual to ideal weight only showed weak relationships with PK parameters. Variance in PK caused large variance in the calculated dose required to maintain a target FVIII trough level during prophylactic treatment. CONCLUSION: Differences in blood sampling schedules should be taken into account when results from different PK studies are compared. However, even with this consideration, PK cannot be predicted from observable patient characteristics but must be determined for the individual. Because the influence of reducing the blood sampling was minor in comparison to the true variance between patients, a reduced blood sampling protocol can be used. Low intrapatient variability supports the use of PK measurements for dose tailoring of FVIII.

Expression of the integrin subunit alpha 9 in the murine embryo.

The alpha 9 integrin subunit is expressed in adult skeletal muscle, visceral smooth muscle, hepatocytes, squamous epithelium, and airway epithelium. The in vivo function of this protein is unknown. Thus far, only a single alpha 9-containing integrin has been identified (alpha 9 beta 1) and only a single ligand (tenascin) has been found for this integrin. In order to gain insight into the potential function of alpha 9 integrin(s), we examined the spatiotemporal distribution of the alpha 9 subunit and tenascin during murine embryogenesis. In all tissues where alpha 9 was expressed, its appearance was associated with other evidence of cell differentiation. In developing airway, visceral, and vascular smooth muscles, the onset of alpha 9 expression either coincided with or immediately followed the expression of alpha-SM actin. Expression of alpha 9 in epithelia was restricted to the choroid plexus and the basal cell layer of squamous epithelia where its appearance coincided with the development of stratification. alpha 9 immunostaining was first detected in developing skeletal musculature when skeletal myotubes formed. Tenascin expression was detected in many, but not all tissues found to express alpha 9. For example, the hair germs of maturing hair follicles exhibited high levels of alpha 9 staining, but no tenascin immunoreactivity was detected either within the hair germ themselves or in the adjacent dermis. In some tissues where tenascin expression colocalized with alpha 9, expression patterns were not synchronous. Although alpha 9 expression was associated with the onset of tissue differentiation, its expression was not limited to terminally differentiated cells. In fact, in the skin, alpha 9 expression appeared restricted to cells known to retain the capacity to proliferate, i.e., basal cells and hair germs. Thus, alpha 9 integrin(s) are not likely to contribute to the early steps in organ formation, but probably play a role in the maturation and/or maintenance of a variety of differentiated tissues. The expression of alpha 9 without its only known ligand, tenascin, suggests the existence of additional ligands.

An upstream Oct-1- and Oct-2-binding silencer governs B29 (Ig beta) gene expression.

The B cell-specific B29 (Igbeta) gene is activated in the earliest B cell precursors and is expressed throughout B cell development. Tissue-specific expression of the murine B29 gene is controlled by a B cell-specific promoter whose activity is governed by a cassette of upstream transcriptional silencers. This study describes a potent new silencer that is located 5' of the previously identified B29 silencer elements, FROG and TOAD. Like these known elements, the new B29 silencer is not restricted to the B29 promoter. Nuclear proteins from all cell lines tested interacted with this A+T-rich sequence, which closely resembled a noncanonical octamer binding motif and also conformed to the consensus sequence for nuclear matrix attachment regions. Interaction of Oct-1 and Oct-2 with the B29 A+T-rich sequence was confirmed using octamer-specific Abs. Oct-1/Oct-2 binding was required for the inhibitory activity of this sequence because mutations that blocked Oct-1/Oct-2 binding also eliminated inhibition of the B29 promoter. This B29 A+T-rich sequence specifically interacted with isolated nuclear matrix proteins in vitro, suggesting that it may also function as a matrix attachment region element. Maintenance of the level of B29 gene expression through the interaction of the minimal promoter and the upstream silencer elements FROG, TOAD, and the A+T-rich Oct-1/Oct-2 binding motif may be essential for normal B cell development and/or function.

Intratumoral interleukin-2 immunotherapy: activation of tumor-infiltrating and splenic lymphocytes in vivo.

Direct intratumoral injection of interleukin-2 (IL-2) was evaluated in a murine model. Balb/c mice received 5 x 10(4) Line 1 alveolar carcinoma cells (L1C2) by subcutaneous injection. On the third day following tumor implantation, mice received injections of IL-2 (5 x 10(3)-5 x 10(4) units) or diluent twice daily, either by i.p. or intratumoral injection, 5 days/week for 3 weeks. Intratumoral injection of 5 x 10(4) units IL-2 significantly reduced tumor volume (P < 0.05 versus control), increased median survival time (P = 0.0001), and resulted in a 23.5% cure rate (P = 0.008). There were no long-term survivors in the other treatment groups. Both tumor-infiltrating lymphocytes (TIL) and splenic lymphocytes isolated directly from IL-2-treated mice demonstrated enhanced cytolytic activity compared to diluent-treated controls. To determine whether non-T-cell-mediated antitumor responses were active in our model, intratumoral immunotherapy was evaluated in athymic Balb/c nu/nu mice. In order to decrease the recruitment of lymphocyte precursors, nude mice were splenectomized and received cyclophosphamide prior to tumor injection and IL-2 therapy. Intratumoral IL-2 immunotherapy also significantly decreased tumor volume in these immunodeficient mice (P < 0.02), but did not lead to long-term survival. We conclude that both TIL and splenic lymphocytes are activated in vivo in response to intratumoral IL-2 immunotherapy, suggesting that intratumoral therapy with IL-2 activates both local and systemic antitumor responses.

Evidence of the key role of metal-molecule bonding in metal-molecule-metal transport experiments.

The transport properties of two oligothiophene derivatives, that differ only by the chemical group coupling to gold, are compared. It is shown that the role of the coupling group in the transport properties can be decoupled from that of the conjugated body of the molecules and that Se is a better electronic coupling group than S. These results are accounted for semiquantitatively within the frame of the scattering theory of transport, using results from ultraviolet photoemission spectroscopy experiments as inputs for the position in energy of the molecular orbitals with respect to the Fermi level of the electrodes.

Microporosity of the substratum regulates differentiation of MDCK cells in vitro.

We have analyzed the ability of the physical substratum to modulate both the ultrastructural and protein synthetic characteristics of the Madin-Darby canine kidney (MDCK) renal cell line. When MDCK cells were seeded on Millipore Millicell CM microporous membrane cell culture inserts they demonstrated a more columnar organization with an increase in cell density sixfold greater than the same cells seeded on conventional plastic substrata. After 1 wk postseeding on the microporous membrane a partial basal lamina was noted, with a contiguous basement membrane being apparent after 2 wk. One-dimensional sodium dodecyl sulfate gel electrophoresis was used to analyze detergent-solubilized proteins from MDCK cells maintained on plastic substrata vs. microporous membranes. When proteins were pulse-labeled with [35S]methionine, a 55 kDa protein was evident in the cytosolic extract of cells grown on collagen, laminin, and nontreated plastic substrata; but this labeled protein was not evident in similar extracts from cells grown on collagen and laminin-coated microporous membranes. To test if the polarized, basement-membrane secreting phenotype of the MDCK cells could be generated on a microporous membrane without pretreatment with any extracellular matrix (ECM) components, cells were seeded on the Millipore Millicell HA (cellulosic) microporous membrane. This type of substrata does not need a coating of ECM components for cell attachment. A partial basement membrane was formed below cells where the basal surface of the cell was planar, but not in areas where the cell formed large cytoplasmic extensions into the filter. This led us to the conclusion that the microporous nature of the substrata can dictate both ultrastructural and protein synthetic activities of MDCK cells. Furthermore, we suggest that both the planar nature of the basal surface and the microporosity of the substrate are corequisites for the deposition of the basement membrane.

Interleukin-2-responsive wound-infiltrating lymphocytes in surgical adjuvant cancer immunotherapy.

Wound-infiltrating lymphocytes (WIL) were assessed in murine models of localized sarcoma and carcinoma to evaluate the role of interleukin-2 (IL-2)-responsive lymphocytes in adjuvant immunotherapy. Following tumor resection, IL-2 or diluent was injected at the surgical site for 6 days. Surgical site tissues were harvested and digested in a triple enzyme mixture, and single cell suspensions were prepared. Thy 1.2+ lymphocytes were isolated by incubating cells with monoclonal anti-Thy 1.2 antibody-coated magnetic beads. Lymphocyte-bead complexes were extracted with a magnet and cultured in medium containing IL-2 (100 units/ml) for 1-3 weeks. Perioperative IL-2 immunotherapy led to a three- to four-fold increase in WIL yield. WIL from IL-2-treated mice also demonstrated enhanced cytolysis of the autologous tumor and bound to activated endothelial cells with greater avidity than did the controls. We conclude that perioperative IL-2 therapy augments the yield, as well as the cytolytic and adhesive properties, of wound-infiltrating lymphocytes.