Needles
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Most cited protocols related to «Needles»
With efficiency and stability as our main concern, we implemented our database on a Linux server, then use MySQL5.0, Apache, and hypertext preprocessor (PHP) for database and web server development. For friendly user interfaces, we used ChemAxon MarvinView applet (
In the advanced search section, the search engine was developed based on the Norbert Haider's MolDB5R package [27] (link). The infrastructure of the advanced search engine is shown in
Although many youth-specific indicators have had to be developed, the survey instrument for the ARYS cohort is largely based on the scales that have been developed as part of the Vancouver Injection Drug Users Study (VIDUS), a prospective cohort study of IDU that has been described in detail previously [13 (link),41 (link)-43 (link)]. The survey instruments have been intentionally coordinated to facilitate the examination of the natural history of injection drug use through to adulthood. Both surveys include sections on sources of income, non-injection and injection drug use (including overdose and binging), interactions with police, incarceration, sexual activity, drug and alcohol treatment, violence, and nutritional needs. Both surveys also include standardized measures for depression (Centre for Epidemiologic Studies Depression Scale [44 ]) and childhood trauma (Childhood Trauma Questionnaire [45 ,46 (link)]), as well as HIV knowledge scales [47 (link)] and a non-standardized self-efficacy scale to evaluate self-efficacy to avoid injection drug use. The youth survey also includes sections on educational background and exposure to injection drug use. The coordination of survey instruments allows us to seek to explore the relationship between established injectors and new initiates into injection drug use.
Most recents protocols related to «Needles»
Example 6
ICP is monitored using a Samba 420 Sensor, pressure transducer, with a Samba 202 control unit (Harvard Apparatus, Holliston, MA). This ICP monitoring system consists of a 0.42 mm silicon sensor element mounted on an optical fiber. A 20-gauge syringe needle is implanted through the cisterna magna to a depth of ˜1 cm. The needle then acts as a guide for insertion of the Samba Sensor and the site of implantation and the open end of the needle are sealed with 100% silicone sealant. A baseline ICP reading is established followed by a water bolus IP injection (20% weight of animal) with or without Compound 1. ICP is monitored until the animal expires from the water load.
Adjusting for the slight rise in ICP observed in the animals when they are monitored without the water bolus injection (
Example 2
Dosage forms B and C were prepared as follows. 20 wt % acetaminophen drug particles were first mixed with the excipient, 80 wt % HPMC of molecular weight 120 kg/mol. The mixture was then combined with a solvent, either DMSO (for preparing dosage form B) or water (for dosage form C). The volume of solvent per mass of excipient was 5.5 ml/g and 3.33 ml/g, respectively, for preparing dosage forms B and C. The drug-excipient-solvent mixture was then extruded through a laboratory extruder to form a uniform viscous paste. The viscous paste was put in a syringe equipped with a hypodermic needle of inner radius, Rn=130 μm (for preparing dosage form B) or Rn 500 μm (for preparing dosage form C). The paste was then extruded through the needle and patterned as a fibrous dosage form with cross-ply arrangement of fibers. The nominal inter-fiber distance in a ply was uniform and equal to 730 μm (for preparing dosage form B) or 2800 μm (for preparing dosage form C). During and after patterning, warm air at a temperature of 60° C. and a velocity of about 2.3 m/s was blown over the fibrous dosage forms for a time, tdry˜40 minutes, to evaporate the solvent and freeze the structure. The process parameters to prepare the dosage forms are summarized in Table 1. After drying, the structure was trimmed to a square disk shaped dosage form of side length, L0˜8 mm. The thickness, H0, of the dosage forms B and C was about 3 mm.
Single fibers B and C were prepared as dosage forms B and C, but without structuring the fibrous extrudate to a dosage form.
Example 1
a. Materials and Methods
i. Vector Construction
1. Virus-Like Particle
As most broadly neutralizing HPV antibodies are derived from the highly conserved N-terminal region of L2, amino acids 14-122 of HPV16 L2 were used to create HBc VLPs. L2 with flanking linker regions was inserted into the tip of the a-helical spike of an HBc gene copy which was fused to another copy of HBc lacking the L2 insert. This arrangement allows the formation of HBc dimers that contain only a single copy of L2, increasing VLP stability (Peyret et al. 2015). This heterodimer is referred to as HBche-L2. A dicot plant-optimized HPV16 L2 coding sequence was designed based upon the sequence of GenBank Accession No. CAC51368.1 and synthesized in vitro using synthetic oligonucleotides by the method described (Stemmer et al., 1995). The plant-optimized L2 nucleotide sequence encoding residues 1-473 is posted at GenBank Accession No. KC330735. PCR end-tailoring was used to insert Xbal and SpeI sites flanking the L2 aa 14-122 using primers L2-14-Xba-F (SEQ ID NO. 1: CGTCTAGAGTCCGCAACCCAACTTTACAAG) and L2-122-Spe-R (SEQ ID NO. 2: G GGACTAGTTGGGGCACCAGCATC). The SpeI site was fused to a sequence encoding a 6His tag, and the resulting fusion was cloned into a geminiviral replicon vector (Diamos, 2016) to produce pBYe3R2K2Mc-L2(14-122)6H.
The HBche heterodimer VLP system was adapted from Peyret et al (2015). Using the plant optimized HBc gene (Huang et al., 2009), inventors constructed a DNA sequence encoding a dimer comprising HBc aa 1-149, a linker (G2S)5G (SEQ ID NO. 39), HBc aa 1-77, a linker GT(G4S)2 (SEQ ID NO. 40), HPV-16 L2 aa 14-122, a linker (GGS)2GSSGGSGG (SEQ ID NO. 41), and HBc aa 78-176. The dimer sequence was generated using multiple PCR steps including overlap extensions and insertion of BamHI and SpeI restriction sites flanking the L2 aa 14-122, using primers L2-14-Bam-F (SEQ ID NO. 3: CAGGATCCGCAACC CAACTTTACAAGAC) and L2-122-Spe-R (SEQ ID NO. 2). The HBche-L2 coding sequence was inserted into a geminiviral replicon binary vector pBYR2eK2M (
2. Recombinant Immune Complex
The recombinant immune complex (RIC) vector was adapted from Kim et al., (2015). The HPV-16 L2 (aa 14-122) segment was inserted into the BamHI and SpeI sites of the gene encoding humanized mAb 6D8 heavy chain, resulting in 6D8 epitope-tagged L2. The heavy chain fusion was inserted into an expression cassette linked to a 6D8 kappa chain expression cassette, all inserted into a geminiviral replicon binary vector (
ii. Agroinfiltration of Nicotiana benthamiana Leaves
Binary vectors were separately introduced into Agrobacterium tumefaciens EHA105 by electroporation. The resulting strains were verified by restriction digestion or PCR, grown overnight at 30° C., and used to infiltrate leaves of 5- to 6-week-old N. benthamiana maintained at 23-25° C. Briefly, the bacteria were pelleted by centrifugation for 5 minutes at 5,000 g and then resuspended in infiltration buffer (10 mM 2-(N-morpholino)ethanesulfonic acid (MES), pH 5.5 and 10 mM MgSO4) to OD600=0.2, unless otherwise described. The resulting bacterial suspensions were injected by using a syringe without needle into leaves through a small puncture (Huang et al. 2004). Plant tissue was harvested after 5 DPI, or as stated for each experiment. Leaves producing GFP were photographed under UV illumination generated by a B-100AP lamp (UVP, Upland, CA).
iii. Protein Extraction
Total protein extract was obtained by homogenizing agroinfiltrated leaf samples with 1:5 (w:v) ice cold extraction buffer (25 mM sodium phosphate, pH 7.4, 100 mM NaCl, 1 mM EDTA, 0.1% Triton X-100, 10 mg/mL sodium ascorbate, 0.3 mg/mL PMSF) using a Bullet Blender machine (Next Advance, Averill Park, NY) following the manufacturer's instruction. To enhance solubility, homogenized tissue was rotated at room temperature or 4° C. for 30 minutes. The crude plant extract was clarified by centrifugation at 13,000 g for 10 minutes at 4° C. Necrotic leaf tissue has reduced water weight, which can lead to inaccurate measurements based on leaf mass. Therefore, extracts were normalized based on total protein content by Bradford protein assay kit (Bio-Rad) with bovine serum albumin as standard.
iv. SDS-PAGE and Western Blot
Clarified plant protein extract was mixed with sample buffer (50 mM Tris-HCl, pH 6.8, 2% SDS, 10% glycerol, 0.02% bromophenol blue) and separated on 4-15% polyacrylamide gels (Bio-Rad). For reducing conditions, 0.5M DTT was added, and the samples were boiled for 10 minutes prior to loading. Polyacrylamide gels were either transferred to a PVDF membrane or stained with Coomassie stain (Bio-Rad) following the manufacturer's instructions. For L2 detection, the protein transferred membranes were blocked with 5% dry milk in PBST (PBS with 0.05% tween-20) overnight at 4° C. and probed with polyclonal rabbit anti-L2 diluted 1:5000 in 1% PBSTM, followed by goat anti-rabbit horseradish peroxidase conjugate (Sigma). Bound antibody was detected with ECL reagent (Amersham).
v. Immunization of Mice and Sample Collection
All animals were handled in accordance to the Animal Welfare Act and Arizona State University IACUC. Female BALB/C mice, 6-8 weeks old, were immunized subcutaneously with purified plant-expressed L2 (14-122), HBche-L2 VLP, L2 RIC, or PBS mixed 1:1 with Imject® Alum (Thermo Scientific, Rockford, IL). In all treatment groups, the total weight of antigen was set to deliver an equivalent 5 μg of L2. Doses were given on days 0, 21, and 42. Serum collection was done as described (Santi et al. 2008) by submandibular bleed on days 0, 21, 42, and 63.
vi. Antibody Measurements
Mouse antibody titers were measured by ELISA. Bacterially-expressed L2 (amino acids 11-128) was bound to 96-well high-binding polystyrene plates (Corning), and the plates were blocked with 5% nonfat dry milk in PBST. After washing the wells with PBST (PBS with 0.05% Tween 20), the diluted mouse sera were added and incubated. Mouse antibodies were detected by incubation with polyclonal goat anti-mouse IgG-horseradish peroxidase conjugate (Sigma). The plate was developed with TMB substrate (Pierce) and the absorbance was read at 450 nm. Endpoint titers were taken as the reciprocal of the lowest dilution which produced an OD450 reading twice the background. IgG1 and IgG2a antibodies were measured with goat-anti mouse IgG1 or IgG2a horseradish peroxidase conjugate.
vii. Electron Microscopy
Purified samples of HBche or HBche-L2 were initially incubated on 75/300 mesh grids coated with formvar. Following incubation, samples were briefly washed twice with deionized water then negatively stained with 2% aqueous uranyl acetate. Transmission electron microscopy was performed with a Phillips CM-12 microscope, and images were acquired with a Gatan model 791 CCD camera.
viii. Statistical Analysis
The significance of vaccine treatments and virus neutralization was measured by non-parametric Mann-Whitney test using GraphPad prism software. Two stars (**) indicates p values <0.05. Three stars (***) indicates p values <0.001.
b. Design and Expression of HBc VLPs and RIC Displaying HPV16 L2
BeYDV plant expression vectors (
To express L2-containing MC, amino acids 14-122 of HPV16 L2 were fused with linker to the C-terminus of the 6D8 antibody heavy chain and tagged with the 6D8 epitope (Kim et al. 2015). A BeYDV vector (
After rigorous genetic optimization, the N. benthamiana system is capable of producing very high levels of recombinant protein, up to 30-50% of the total soluble plant protein, in 4-5 days (Diamos et al. 2016). Using this system, we produced and purified milligram quantities of fully assembled and potently immunogenic HBc VLPs displaying HPV L2 through a simple one-step purification process (
c. Purification and Characterization of HBche-L2 and L2 RIC
To assess the assembly of HBc-L2 VLP, clarified plant extracts containing either HBche-L2 or HBche were analyzed by sucrose gradient sedimentation. HBche-L2 sedimented largely with HBche, which is known to form VLP, though a small increase in density was observed with HBche-L2, perhaps due to the incorporation of L2 into the virus particle (
L2 RIC was purified from plant tissue by protein G affinity chromatography. By SDS-PAGE, an appropriately sized band was visible >150 kDa that was highly pure (
d. Mouse Immunization with HBche-L2 and L2 RIC
Groups of Balb/c mice (n=8) were immunized, using alum as adjuvant, with three doses each of 5 μg L2 delivered as either L2 alone, HBche-L2 VLP, L2 RIC, or a combination of half VLP and half RIC. VLP and RIC, alone or combined, greatly enhanced antibody titers compared to L2 alone by more than an order of magnitude at all time points tested (
In vitro neutralization of HPV16 pseudovirions showed that the VLP and RIC groups greatly enhanced neutralization compared to L2 alone (
In this study, by displaying amino acids 11-128 on the surface of plant-produced HBc VLPs, L2 antibody titers as high as those seen with L1 vaccines were generated (
Mice immunized with L2 alone had highly variable antibody titers, with titers spanning two orders of magnitude. By contrast, the VLP and VLP/RIC groups had much more homogenous antibody responses, with no animals below an endpoint titer of 1:1,000,000 (
Fc gamma receptors are present on immune cells and strongly impact antibody effector functions such as antibody-dependent cell-mediated cytotoxicity and complement-dependent cytotoxicity (Jefferis 2009). In mice, these interactions are controlled in part by IgG subtypes. IgG1 is associated with a Th2 response and has limited effector functions. By contrast, IgG2a is associated with a Th1 response and more strongly binds complement components (Neuberger and Raj ewsky 1981) and Fc receptors (Radaev 2002), enhancing effector functions and opsonophagocytosis by macrophages (Takai et al. 1994). Immunization with L2 alone was found to produce low levels of IgG2a, however immunization with RIC and VLP produced significant increases in IgG2a titers. VLP-containing groups in particular showed a 3-fold increase in the ratio of IgG2a to IgG1 antibodies (
The glycosylation state of the Fc receptor also plays an important role in antibody function. Advances in glycoengineering have led to the development of transgenic plants with silenced fucosyl- and xylosyl-transferase genes capable of producing recombinant proteins with authentic human N-glycosylation (Strasser et al. 2008). Antibodies produced in this manner have more homogenous glycoforms, resulting in improved interaction with Fc gamma and complement receptors compared to the otherwise identical antibodies produced in mammalian cell culture systems (Zeitlin et al. 2011; Hiatt et al. 2014; Strasser et al. 2014; Marusic et al. 2017). As the known mechanisms by which RIC vaccines increase immunogenicity of an antigen depend in part on Fc and complement receptor binding, HPV L2 RIC were produced in transgenic plants with silenced fucosyl- and xylosyl-transferase. Consistent with these data, we found that L2 RIC strongly enhanced the immunogenicity of L2 (
e. Neutralization of HPV Pseudovirions
Neutralization of papilloma pseudoviruses (HPV 16, 18, and 58) with sera from mice immunized IP with HBc-L2 VLP and L2(11-128) showed neutralization of HPV 16 at titers of 400-1600 and 200-800, respectively (Table 1). More mice IP-immunized with HBc-L2 VLP had antisera that cross-neutralized HPV 18 and HPV 58 pseudoviruses, compared with mice immunized with L2(11-128). Anti-HBc-L2 VLP sera neutralized HPV 18 at titers of 400 and HPV 58 at titers ranging from 400-800 (Table 1), while anti-L2(11-128) sera neutralized HPV 18 at a titer of 200 and HPV 58 at a titer of 400 (Table 1). None of the sera from intranasal-immunized mice demonstrated neutralizing activity, consistent with lower anti-L2 titers for intranasal than for intraperitoneal immunized mice.
Example 3
Probe Materials
A number of porous materials were tested to generate charged droplets for mass spectrometry. The materials were shaped into triangles having sharp tips and sample solution was then applied to the constructed probes. Data herein show that any hydrophilic and porous substrate could be used successfully, including cotton swab, textile, plant tissues as well as different papers. The porous network or microchannels of these materials offered enough space to hold liquid and the hydrophilic environment made it possible for liquid transport by capillary action. Hydrophobic and porous substrates could also be used successfully with properly selected hydrophobic solvents.
For further investigation, six kinds of commercialized papers were selected and qualitatively tested to evaluate their capabilities in analyte detection. Filter papers and chromatography paper were made from cellulose, while glass microfiber filter paper was made from glass microfiber.
It was hypothesized that the glass fiber paper was working on mode II and prohibiting efficient droplet generation, due to the relative large thickness (˜2 mm). This hypothesis was proved by using a thin layer peeled from glass fiber paper for cocaine detection. In that case, the intensity of the background increased and a cocaine peak was observed. All filter papers worked well for cocaine detection, (
Probe Shape and Tip Angle
Many different probe shapes were investigated with respect to generating droplets. A preferred shape of the porous material included at least one tip. It was observed that the tip allowed ready formation of a Taylor cone. A probe shape of a triangle was used most often. As shown in
Example 28
A typical protocol used for the synthesis of the PNAEP67-PnBA500 diblock copolymer was as follows: PNAEP67 macro-CTA (0.185 g, 14.6 μmol), deionised water (4.501 g, corresponding to a 20% w/w solution) and KPS (1.320 mg, 4.9 μmol; PNAEP67/KPS=3.0) were weighed into a 10 mL round-bottom flask charged with a magnetic flea. HCl (10 μL, 0.2 M) was added to reduce the pH to 3.0. This flask was then immersed in an ice bath, and the solution was degassed with nitrogen for 30 min. nBA (1.500 g) was weighed into a separate 14 mL vial and degassed with nitrogen in an ice bath for 30 min. An AsAc stock solution (0.01% w/w) was weighed into a second 14 mL vial and degassed with nitrogen in an ice bath for 30 min. After 30 min nBA (1.05 ml, 7.32 mmol; target DP=500) was added to the flask using a degassed syringe and needle under nitrogen. The flask contents were then stirred vigorously to ensure thorough mixing and degassed for 5 min before being immersed in an oil bath set at 30° C. After 1 min, AsAc (0.09 ml, 4.9 μmol; KPS/AscAc molar ratio=1.0) was added to the flask. The nBA polymerisation was allowed to proceed for 1 h before being quenched by exposing the reaction solution to air and immersing the reaction vial in an ice bath. 1H NMR spectroscopy analysis of the disappearance of vinyl signals indicated a final nBA conversion of 99%. Chloroform GPC analysis of this copolymer indicated a Mn of 86.6 kg mol−1 and an Mw/Mn of 1.56. Other diblock copolymer compositions were obtained by adjusting the nBA/PNAEP67 molar ratio.
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More about "Needles"
These sharp, hollow instruments made of stainless steel or other materials are essential for a wide range of applications, from routine vaccinations to sophisticated cell and tissue extraction techniques.
In addition to their use in clinical settings, needles are also vital in research laboratories.
Researchers often rely on needles to inject or extract fluids, cells, or other biological samples during experiments.
For example, when working with cell culture systems, researchers may use needles to add media like DMEM, Matrigel, or Penicillin/streptomycin, as well as to collect samples for analysis using tools like the RNeasy Mini Kit or TRIzol.
Proper needle selection and usage is crucial for ensuring accurate, reproducible results.
Factors such as needle gauge, length, and bevel design can impact the ease of use, sample quality, and potential for contamination.
Researchers can utilize platforms like PubCompare.ai to quickly identify the optimal needle protocols and products for their specific Needles-related studies, enhancing the accuracy and reproducibility of their work.
When working with sensitive biological samples, researchers may also need to consider additional precautions, such as using a stereotaxic frame for precise needle positioning or incorporating protease inhibitor cocktails to preserve sample integrity.
The BD Vacutainer system is another commonly used tool for reliable blood collection and storage.
By leveraging the insights and resources available through PubCompare.ai, researchers can save time, improve the quality of their Needles-related studies, and ultimately advance scientific understanding and medical care.
Whether in the clinic or the lab, needles remain an indispensable tool for a wide range of critical procedures.