Suitable Purity Research Articles

Efficient purification of soluble receptor for advanced glycation end-products from Sus scrofa lung tissue and synthesis of its binding ligand, glycated bovine serum albumin

A receptor for advanced glycation end products (RAGE) has emerged as a crucial player in various pathological conditions due to its involvement in inflammation and cellular dysfunction. Its soluble isoform, sRAGE, has garnered significant attention for its competitive inhibitory effects and potential therapeutic applications. However, obtaining sRAGE with appropriate glycosylation patterns for binding to glycated proteins has been challenging, often requiring costly expression systems. Here, we present a novel approach for producing and purifying sRAGE from Sus scrofa lungs, bypassing the need for expensive expression systems. Previous protocols for sRAGE extraction faced reproducibility issues due to high viscosity and haemoglobin content of the solution. To address this, we developed a method for selective haemoglobin precipitation using a zinc-containing buffer, enabling purification via various chromatographic methods. Through a combination of chromatographic techniques, we obtained sRAGE in suitable purity, identified using HPLC-MS/MS. Additionally, producing glycated proteins for RAGE receptor activation often involved lengthy protocols or inadequate separation from reactants. Thus, we devised a rapid method for producing and purifying pure BSA glycated with ribose, addressing a critical gap in the field. Functional studies, conducted using Native PAGE, demonstrated the capability of purified proteins to bind to each other.

Translation of hyaluronic acid-based vitreous substitutes towards current regulations for medical devices.

Hydrogel-based vitreous substitutes have the potential to overcome the limitations of current clinically used endotamponades. With the goal of entering clinical trials, the present study aimed to (I) transfer the material synthesis of hyaluronic acid-based hydrogels into a routine, pharmaceutical-appropriate production and (II) evaluate the properties of the vitreous substitutes in terms of the current regulations for medical devices (MDR/ISO standards). The multistep manufacturing process of the vitreous substitutes, including the modification of hyaluronic acid with glycidyl methacrylate, photocopolymerization with N-vinylpyrrolidone, and successive hydrogel purification, was developed under laboratory conditions, characterized using 1 H-NMR, FT-IR and UV/Vis spectroscopies and HPLC, and transferred towards a pharmaceutical production environment considering GMP standards. The optical and viscoelastic characteristics of the hyaluronic acid-based hydrogels were compared with those of extracted human vitreous and silicone oil. The effect of the hydrogels on the metabolic activity, proliferation and apoptosis of fibroblast (MRC-5, BJ, L929), retinal pigment epithelial (ARPE-19, hiPSC-derived RPE) and photoreceptor cells (661W) was studied as well as their mucosal tolerance via a HET-CAM assay. Hyaluronic acid-based hydrogels having a suitable purity, sterility, high transparency (>90%), appropriate refractive index (1.3365) and viscoelasticity (G' > G″) were prepared in a standardized manner under controlled process conditions. The metabolic activity, proliferation and apoptosis of various cell types as well as egg choroid were unaffected by the hyaluronic acid-based vitreous substitutes, demonstrating their biocompatibility. The present study demonstrates the successful transferability of the crucial synthesis steps of hyaluronic acid-based hydrogels into a routine, GMP-compliant production process while achieving the optical and viscoelastic properties, biocompatibility and purity required for their clinical use as vitreous substitutes.

Low-Cost and Efficient Nickel Nitroprusside/Graphene Nanohybrid Electrocatalysts as Counter Electrodes for Dye-Sensitized Solar Cells.

Novel nickel nitroprusside (NNP) nanoparticles with incorporated graphene nanoplatelets (NNP/GnP) were used for the first time as a low-cost and effective counter electrode (CE) for dye-sensitized solar cells (DSSCs). NNP was synthesized at a low-temperature (25 °C) solution process with suitable purity and crystallinity with a size range from 5 to 10 nm, as confirmed by different spectroscopic and microscopic analyses. The incorporation of an optimized amount of GnP (0.2 wt%) into the NNP significantly improved the electrocatalytic behavior for the redox reaction of iodide (I−)/tri-iodide (I3−) by decreasing the charge-transfer resistance at the CE/electrolyte interface, lower than the NNP- and GnP-CEs, and comparable to the Pt-CE. The NNP/GnP nanohybrid CE when applied in DSSC exhibited a PCE of 6.13% (under one sun illumination conditions) with the Jsc, Voc, and FF of 14.22 mA/cm2, 0.628 V, and 68.68%, respectively, while the PCE of the reference Pt-CE-based DSSC was 6.37% (Jsc = 14.47 mA/cm2, Voc = 0.635 V, and FF = 69.20%). The low cost of the NNP/GnP hybrid CE with comparable photovoltaic performance to Pt-CE can be potentially exploited as a suitable replacement of Pt-CE in DSSCs.

A novel approach of recombinant laterosporulin production using the N-SH2 domain of SHP-2

BackgroundThe current study was aimed at evaluating the role of the N-SH2 domain of SHP-2 as a partner protein in the expression of a toxic peptide, laterosporulin (LTS). We also investigated its effects on the formation of the disulfide bond and functional folding of the peptide in vitro. The N-SH2-LTS protein was expressed as a His-tagged fusion protein, capable of undergoing enzymatic cleavage.ResultsBased on the data presented herein, the total yield of the folded fusion protein from inclusion bodies was found to be about 105 mg/l, demonstrating a high-level of heterologous expression. After enzymatic cleavage, 1.5 mg of the folded recombinant laterosporulin was obtained from each 10 mg of the fusion protein. The purity of the recombinant laterosporulin was analyzed by RP-HPLC, to yield peptides with suitable purity (85%).ConclusionsOur findings indicated the advantages of using the N-SH2 domain of SHP-2 as a rapid and easy approach not only in producing easy target proteins but also in its function as a chaperone. N-SH2 domain of SHP-2 can influence on the purification of laterosporulin at reasonable yield and in a cost-effective fashion. The N-SH2 domain of SHP-2 as a protein chaperone may be potentially favorable to produce other proteins with disulfide bonds.

A Comparative Study of Compact Multiband Bio-Inspired Asymmetric Microstrip Fed Antennas (BioAs-MPAs) for Wireless Applications

A comparative analysis of compact multiband bio-inspired Asymmetric microstrip fed antennas (BioAs-MPAs) is presented in this paper for the first time. The proposed antennas are based on semi-Carica papaya-leaf shaped, semi-Monstera deliciosa-leaf shaped, semi-Vitis vinifera shaped, Defected Ground Structure (DGS) and L-slit techniques. The antennas are built on a 33 × 15 mm2 Rogers duroid 5880 substrate. The modelling equations for resonant frequencies of the proposed arbitrarily shaped radiating patch is based on modified circular patch modelling equations. The semi-Carica papaya-leaf antenna operates at 2.4 GHz and 4.4 GHz, Monstera deliciosa-leaf antenna operates at 2.6 GHz, 4.4 GHz and 5.5 GHz, while Vine-leaf antenna operates at 2.5 GHz and 5.4 GHz. The proposed BioAs-MPAs antennas radiation patterns at E-plane are Bi-directional in all the operating frequencies with suitable X-Pol purity and have Omnidirectional radiation patterns at H-Plane in all the operating frequencies. As a result of the analysis, it was found that each of the bio-inspired structures has its unique merit over the others. Owing to the small size, stable radiation pattern, acceptable gain and high radiation efficiency, the proposed BioAs-MPAs antennas are suitable for ISM band, Bluetooth, Wi-Fi, WiMAX, LTE, UMTS, Sub6 GHz 5 G band, ZigBee and RF-Altimeter used in unmanned aerial vehicle and Aviation industry.

New excitation functions for proton induced reactions on natural gadolinium up to 70 MeV with focus on 149Tb production

Terbium is one of the most interesting elements for new potential theranostics applications. Indeed, the physical properties of four of its radionuclides (149Tb, 152Tb, 155Tb, 161Tb) allow their use in each main applications of nuclear medicine. 149Tb is the lowest mass alpha emitter with suitable physical properties for receptor-targeted alpha therapy (TAT), and the only one among the radiolanthanides. Currently 149Tb is only produced through spallation reactions induced by high-energy proton beam coupled with mass separation to obtain suitable purity. The aim of the present work is to investigate the production of 149Tb using commercial cyclotrons by irradiation of natural gadolinium target. New excitation functions for proton-induced nuclear reactions on natural gadolinium have been measured. Our results extend current knowledge up to 70 MeV and are in good agreement with existing data at low energy. From this new set of data, production yield estimations are calculated and discussed.

Study of the Effect Operational Parameters on the Super critical Extraction Efficient Related to Sunflower Oil Seeds

Super critical extraction is a new method for separation of efficient processes and effective method for extracting a necessary foundation of solid or liquid material are suitable purity. Seed sunflower seed oil is the second one year after soy which is cultivated for its oil on the world. In this article, sunflower seed oil is extracted by liquid carbon dioxide in super critical conditions. Effects of temperature, pressure and grain size in the rate of extraction efficiency were the change in particle size among other parameters extraction efficiency because they have a role and the smaller the size, the efficiency is higher. Results proves is that temperature changes and pressure changes in comparison with particle size in the process of extraction efficiency was less effect because of reduced grain size increased 75 percent extraction efficiency. While the temperature increase of 16 percent and increasing pressure about 5 percent increase in extraction efficiency was observed.

Short-Duration Rapid Chilling of Mastectomy Specimens Does Not Interfere With Breast Cancer Biomarker and Molecular Testing.

A thorough gross examination of specimens for breast cancer requires the tissue to be very thinly sectioned, which is often difficult in large mastectomy samples. We have implemented rapid chilling of mastectomy specimens before formalin fixation. To evaluate the effects of rapid chilling of breast tissue on subsequent biomarker and molecular testing. Mastectomy specimens were chilled at -80°C for 20 minutes to facilitate uniform sectioning of tissue at 4-mm intervals and enhance proper fixation and identification of small lesions. The integrity of chilled tissue for ancillary and molecular testing was assessed. We identified patients who were diagnosed with breast cancer on biopsy at outside institutions and subsequently underwent mastectomy at our institution during 2010-2014. We compared the results of biomarker testing performed on biopsy tissue with those performed on mastectomy tissue. The quantity and quality of DNA extracted from formalin-fixed, paraffin-embedded (FFPE) mastectomy tissue with invasive carcinoma were assessed by using spectrophotometry and polymerase chain reaction. All Oncotype DX reports from 2011-2014 were reviewed to identify any documented evidence of assay interference caused by rapid chilling of tissue. We found essentially 100% concordances in estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 gene ERBB2 (HER2/neu) studies. Extracted tumor DNA showed suitable purity and concentration that produced amplified fragments of 300 to 400 base pair lengths by polymerase chain reaction of FFPE tissue. No documented assay interferences were found in the Oncotype DX reports. Short-duration rapid chilling of mastectomy tissue improves gross examination, optimally preserves DNA, allows for molecular testing, and does not interfere with biomarker assessment.

Rapid and Simple Method for the Extraction of Genomic DNA from Tobacco (Nicotiana tabacum L.) Seedlings

Abstract Tobacco (Nicotiana tabacum L.) plants are known to present high levels of secondary metabolites that increase with the plant age. Molecular biology techniques like restriction enzyme digestion and PCR, requires as pre-requisite the isolation of genomic DNA of suitable purity, good quality and with low levels of contaminants. Several methods to isolate pure and intact tobacco DNA for molecular research purposes have been developed. In this work, a combination between a tobacco seed germination technique using gibberellic acid and a fast and simple genomic DNA extraction method from 14-days old tobacco seedlings to reduce the secondary metabolites levels in the final samples was presented. Ten tobacco genotypes were used to evaluate this method. The DNA concentrations were in a range between 0.73 μg/μL to 1.47 μg/μL for Habana-2000 cv. and Criollo cv., respectively. The absorbance ratios values to determine DNA quality were acceptable. This method allows the obtaining of high molecular weight DNA suitable for digestion with restriction enzymes, EcoRI and BamHI. Tobacco seedlings DNA in a short period of time, in a simple way and with a low cost, was obtained with this extraction method.

Single-electron gap in the spectrum of twisted bilayer graphene

We investigate the gap in the single-electron spectrum of twisted bilayer graphene. In a perfect infinite lattice of a twisted bilayer, the gap varies exponentially in response to weak changes of the twist angle. Such a large sensitivity makes theoretical predictions of the gap nearly impossible, since experimentally the twist angle is always known with finite accuracy. To address this issue, we numerically study finite clusters of twisted bilayer graphene. For finite systems, changing the twist angle causes a gradual crossover between gapless and gapped regimes. The crossover occurs when the finite-size quantization energy becomes comparable to the matrix elements responsible for the generation of the gap. We further argue that disorder scattering can induce similar crossover, in which the mean-free path plays the same role as the system size for the finite clusters. It is demonstrated that, to observe the gap experimentally, it is necessary to have a sample of suitable purity, and to possess the ability to tune the twist angle accurately.

Development of Certified Reference Materials for Diarrhetic Shellfish Poisoning Toxins, Part 1: Calibration Solutions.

Okadaic acid (OA) and its analogs dinophysistoxins-1 (DTX1) and -2 (DTX2) are lipophilic polyethers produced by marine dinoflagellates. These toxins accumulate in shellfish and cause diarrhetic shellfish poisoning (DSP) in humans. Regulatory testing of shellfish is essential to safeguard public health and for international trade. Certified reference materials (CRMs) play a key role in analytical monitoring programs. This paper presents an overview of the interdisciplinary work that went into the planning, production, and certification of calibration-solution CRMs for OA, DTX1, and DTX2. OA and DTX1 were isolated from large-scale algal cultures and DTX2 from naturally contaminated mussels. Toxins were isolated by a combination of extraction and chromatographic steps with processes adapted to suit the source and concentration of each toxin. New 19-epi-DSP toxin analogs were identified as minor impurities. Once OA, DTX1, and DTX2 were established to be of suitable purity, solutions were prepared and dispensed into flame-sealed glass ampoules. Certification measurements were carried out using quantitative NMR spectroscopy and LC-tandem MS. Traceability of measurements was established through certified external standards of established purity. Uncertainties were assigned following standards and guidelines from the International Organization for Standardization, with components from the measurement, stability, and homogeneity studies being propagated into final combined uncertainties.

The choice of endogenous controls in exosomal microRNA assessments from biofluids.

The assessment of differentially expressed microRNAs in patients and healthy controls is important to identify potential tumor biomarkers. Recently, it has been shown that the microRNA levels in exosomes are more correlated with the clinical-pathological variables than vesicle-free microRNAs (miRNAs) in biofluids; therefore, there is an increasing interest in these specific evaluations. However, these measurements can be affected by experimental problems that not always are evaluated and/or by inadequate procedural choices. In particular, exosome isolation and miRNA extraction procedures are crucial to avoid contaminations, and even the choice of the most suitable purity controls is important. Moreover, a stable endogenous RNA should be used for normalization of miRNA expression obtained by reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) in order to make these measures comparable among different samples. A rushed choice of the endogenous control can bias study conclusions without revealing inconsistencies. Unfortunately, a few studies systematically identified the best normalizer for their specific experimental context. Instead, sometimes, the normalization procedures were performed in a disputable way or the normalizer choices simply based on the previous literature. Here, we reviewed the studies where the exosomal miRNA profiling was assessed in human biofluids to point out the adopted procedures and the specific endogenous controls chosen for normalization.

Purification and analysis of endogenous human RNA exosome complexes.

As a result of its importance in key RNA metabolic processes, the ribonucleolytic RNA exosome complex has been the focus of intense study for almost two decades. Research on exosome subunit assembly, cofactor and substrate interaction, enzymatic catalysis and structure have largely been conducted using complexes produced in the yeast Saccharomyces cerevisiae or in bacteria. Here, we examine different populations of endogenous exosomes from human embryonic kidney (HEK) 293 cells and test their enzymatic activity and structural integrity. We describe methods to prepare EXOSC10-containing, enzymatically active endogenous human exosomes at suitable yield and purity for in vitro biochemistry and negative stain transmission electron microscopy. This opens the door for assays designed to test the in vitro effects of putative cofactors on human exosome activity and will enable structural studies of preparations from endogenous sources.

Evaluation of the non-toxic mutant of the diphtheria toxin K51E/E148K as carrier protein for meningococcal vaccines

Diphtheria toxin mutant CRM197 is a common carrier protein for glycoconjugate vaccines, which has been proven an effective protein vector for, among others, meningococcal carbohydrates. The wide-range use of this protein in massive vaccine production requires constant increase of production yields and adaptability to an ever-growing market. Here we compare CRM197 with the alternative diphtheria non-toxic variant DT-K51E/E148K, an inactive mutant that can be produced in the periplasm of Escherichia coli. Biophysical characterization of DT-K51E/E148K suggested high similarity with CRM197, with main differences in their alpha-helical content, and a suitable purity for conjugation and vaccine preparation. Meningococcal serogroup A (MenA) glycoconjugates were synthesized using CRM197 and DT-K51E/E148K as carrier proteins, obtaining the same conjugation yields and comparable biophysical profiles. Mice were then immunized with these CRM197 and DT-K51E/E148K conjugates, and essentially identical immunogenic and protective effects were observed. Overall, our data indicate that DT-K51E/E148K is a readily produced protein that now allows the added flexibility of E. coli production in vaccine development and that can be effectively used as protein carrier for a meningococcal conjugate vaccine.

Stains of ejaculated pre and post-vasectomy: Purity and sufficient quantity of recovered DNA after 10 years of storage

Vasectomy is a widely used method of contraception. The absence of spermatozoa in the ejaculate of azoospermic individuals increases the difficulty of extracting DNA for analysis, especially if the biological samples are in the form of spots and stored for years. The aim of this study is to evaluate the possibility of obtaining autosomal and Y-STR profiles from stains containing the ejaculate of individuals pre and post-vasectomy, stored in cotton fabric for a period of 10 years. Samples from 28 (twenty eight) individuals: semen pre-vasectomy and seminal fluid (post-vasectomy) stains, stored from 2004 to 2014 at room temperature were used. Three cutouts of 1.5cm in diameter (punch) were taken from central region of each spot. It was used the QIAamp DNA Mini kit (Qiagen) to extract DNA with an adapted protocol followed by quantification by Nanodrop equipment. Genetic profiles were obtained using ESI17PowerPlexR (Promega). Capillary electrophoresis was performed on the ABI PRISM 3500XL DNA Analyzer. The DNA extraction was successful in all punch analyzed, and its concentration ranged from 1.1ng/uL to 23.3ng/uL in the pre- vasectomy and from 0.8ng/uL to 7ng/uL in postvasectomy punch. The samples had suitable purity, reflecting the presence of few contaminants. Currently, the techniques of DNA amplification are extremely sensitive and capable of assessing human DNA in small quantities generating partial or full profiles, trespassing situations such as long storage periods in cotton fabric. These data can be used as a benchmark for forensic analysis in cases of semen analysis.

Screening of L-histidine-based ligands to modify monolithic supports and selectively purify the supercoiled plasmid DNA isoform.

The growing demand of pharmaceutical-grade plasmid DNA (pDNA) suitable for biotherapeutic applications fostered the development of new purification strategies. The surface plasmon resonance technique was employed for a fast binding screening of l-histidine and its derivatives, 1-benzyl-L-histidine and 1-methyl-L-histidine, as potential ligands for the biorecognition of three plasmids with different sizes (6.05, 8.70, and 14 kbp). The binding analysis was performed with different isoforms of each plasmid (supercoiled, open circular, and linear) separately. The results revealed that the overall affinity of plasmids to l-histidine and its derivatives was high (KD > 10(-8) M), and the highest affinity was found for human papillomavirus 16 E6/E7 (K(D) = 1.1 × 10(-10) M and KD = 3.34 × 10(-10) M for open circular and linear plasmid isoforms, respectively). L-Histidine and 1-benzyl-L-histidine were immobilized on monolithic matrices. Chromatographic studies of L-histidine and 1-benzyl-L-histidine monoliths were also performed with the aforementioned samples. In general, the supercoiled isoform had strong interactions with both supports. The separation of plasmid isoforms was achieved by decreasing the ammonium sulfate concentration in the eluent, in both supports, but a lower salt concentration was required in the 1-benzyl-L-histidine monolith because of stronger interactions promoted with pDNA. The efficiency of plasmid isoforms separation remained unchanged with flow rate variations. The binding capacity for pDNA achieved with the l-histidine monolith was 29-fold higher than that obtained with conventional L-histidine agarose. Overall, the combination of either L-histidine or its derivatives with monolithic supports can be a promising strategy to purify the supercoiled isoform from different plasmids with suitable purity degree for pharmaceutical applications.

Morphology of Ruthenium Particles for Methanation under Reactive Conditions

The potential of hydrogen as a future energy carrier is only fully unleashed if fuel processors generating hydrogen of a suitable purity can be engineered. Selective methanation of CO can be used as a first step for cleaning up feed gas for e.g. proton exchange membrane (PEM) fuel cells [1] where CO poison the platinum electrodes and for removing oxygen containing compounds in hydrogen used in ammonia plants [2].

Genetic variability of microsatellites in autochthonous Podolian cattle breeds in Croatia

The aim of the study was to analyse the status of the genetic structure of two autochthonous Croatian Podolian breeds (Istrian cattle and Slavonian Syrmian Podolians). The study comprised 20 randomly selected blood samples of each cattle breed. The genotyping was performed on 11 microsatellites (TGLA227, BM2113, TGLA53, ETH10, SPS115, TGLA126, TGLA122, INRA23, ETH3, ETH225, BM1824) as recommended by International Society of Animal Genetics and Food and Agriculture Organization. The procedure enabled the identification of 423 (96.14%) genotypes, indicating the validity of DNA analyses in blood samples and adequacy of the selected microsatellite markers. Likewise, there was the total number of 203 alleles with minimal differences among the studied groups. The differences (p> 0.05)were observed within the genotypes of the studied groups regarding the microsatellite loci. The distribution of the genetic relationship was presented by Wright F coefficients. The FIShad negative values for the TGLA 227 locus in both studied groups and for ETH3, ETH225 and BM1834 loci in the Slavonian Syrmian Podolians. This obtained data with relative high values of heterozygosity also shows a genetical influence of other breeds. Almost all FITvalues were appropriate (0.31905) as a result of excessive selection effects. The mean value of FST(0.07336) indicates that the average degree of genetic variability of the studied breeds was not significantly different despite certain differences in individual loci. The observed specific polymorphism of loci shows that the Istrian cattle and the Slavonian Syrmian Podolians have similar genetic characteristics, but also that there are certain differences between the breeds and even inter-breed differences. The findings indicate a relationship between the breeds and their suitable purity for interbreeding but they also indicate certain danger to certain parts of genome within the studied species. The results can be applied in the protection and breeding programs for the preservation of autochtonous Croatian Podolian breeds.

Preimplantation factor negates embryo toxicity and promotes embryo development in culture

Preimplantation factor (PIF) is secreted by viable mammalian embryos and promotes implantation and trophoblast invasion. Whether PIF also has a direct protective or promoting effect on the developing embryo in culture is unknown. This study examined the protective effects of synthetic PIF (sPIF) on embryos cultured with embryo toxic serum (ETS) from recurrent pregnancy loss patients ( n = 14), by morphological criteria at 72 h of culture, and determined sPIF-promoting effect on singly cultured bovine IVF embryo development. sPIF negated the ETS-induced effect by increasing mouse blastocyst rate versus other embryonic stages (odds ratio (OR) 2.01, 95% confidence intervals (CI) 1.14–3.55, chi-squared = 12.74, P = 0.002), increased blastocyst rate (39.0% versus 23.7% ETS alone) and lowered embryo demise rate (11.0% versus 28.8%, OR 0.24, 95% CI 0.11–0.54), which was not replicated by scrambled PIF or the control. sPIF added to bovine embryos for 3 days promoted development at day 7 of culture (11% versus 0%, chi-squared = 4.0, P = 0.045). In conclusion, sPIF prevented embryo demise caused by exposure to ETS and promoted development of singly cultured bovine IVF embryos following short-term exposure. sPIF-based therapy for reducing recurrent pregnancy loss and improving lagging cultured IVF embryo development should be explored. Preimplantation factor (PIF) is a novel peptide, secreted by the embryo at the 2-cell stage. It is present throughout viable pregnancy but absent in non-viable pregnancy. PIF has essential immune-modulatory, acceptance and maintenance effects on the maternal system for embryo implantation, creating the necessary environment in the uterus and helping better embedding of the placenta. Herein we investigate in two complementary models whether PIF can help embryos survive under adverse conditions, protect against recurrent pregnancy loss and promote lagging embryo development. PIF’s synthetic analogue (sPIF) is available at suitable purity for human use and its use is proposed in physiological range doses. sPIF administration strongly suggested a targeted and safe treatment regimen, successfully negating the toxicity present in the blood (serum) of patients suffering from recurrent miscarriages in the relevant pooled mouse embryo model used. sPIF showed an equally important beneficial effect to prevent suboptimally developed embryo demise and improve their development. In a (single bovine) IVF model, highly relevant for low-responder human embryos that produce low-quality but viable embryos, sPIF increased embryo survival under adverse conditions. To document sPIF’s specific effect, an inactive, same-composition (scrambled) protein was tested, which showed no effect. To evidence sPIF’s safety and unique needs-based action, high concentrations added to optimally cultured embryos equally showed no effect. We conclude that sPIF administration may specifically reduce cases of repeat miscarriage and improve viable but suboptimal embryo survival. These added observations help complete PIF’s overall crucial function in accommodating and facilitating successful pregnancy.

Demineralised water for pharmaceutical purposes.

Summary Demineralised water, prepared from tap-water by treatment with mixed anion and cation exchange resins, has been examined by means of the tests of the British Pharmacopœia for distilled water. It has also been subjected to a more detailed analysis. The results show that providing a correct demineralising technique is used and that only water of specific resistance greater than 1 megohm cm., is collected, the purity of the product is at least equal to that of distilled water, B.P. It is suggested that the monograph on distilled water in the British Pharmacopœia should be amended so that demineralised water of suitable purity can be included within it.