Weak Reaction Research Articles

Occurrence and spatiotemporal distribution of PAHs and OPAHs in urban agricultural soils from Guangzhou City, China

The occurrence of polycyclic aromatic hydrocarbon (PAH) derivatives in the environment is of growing concern because they exhibit higher toxicity than their parent PAHs. This study evaluated the large-scale occurrence and spatiotemporal distribution of 16 PAHs and 14 oxygenated PAHs (OPAHs) in urban agricultural soils from seven districts of Guangzhou City, China. Linear correlation analysis was conducted to explore the relationship between PAH and OPAH occurrence and a series of parameters. The compositional analysis, principal component analysis, diagnostic ratios, and principal component analysis coupled with a multiple linear regression model were used to identify the sources of PAHs and OPAHs in the soils. The average concentrations of ΣPAHs and ΣOPAHs (59.6 ± 31.1–213 ± 115.5 μg/kg) during the flood season were significantly higher than those during the dry season (42.1 ± 13.3–157.2 ± 98.2 μg/kg), which were due to relatively strong wet deposition during the flood season and weak secondary reactions during the dry season. Linear correlation analysis showed that soil properties, industrial activities, and agricultural activities (r = 0.27–0.96, p < 0.05) were responsible for the spatial distribution of PAHs during the dry season. The PAH distribution was mainly affected by precipitation during the flood season. The concentrations of ΣOPAHs were only related to the soil properties during the dry season because their occurrence was sensitive to secondary reactions, climate and meteorological conditions, and their water solubility. Our results further showed that coal combustion and traffic emissions were the dominant origins of PAHs and OPAHs during both the seasons. Wet deposition and runoff-induced transport also contributed to PAH and OPAH occurrence during the flood season. The results of this study can improve our understanding of the environmental risks posed by PAHs and OPAHs.

The possible protective role of vitamin C versus melatonin on potassium dichromate induced changes in rat thyroid gland: light and electron microscopic study

ABSTRACT Potassium dichromate is widely used in various laboratory and industrial applications. Vitamin C and melatonin are well-known antioxidants. Study the microscopic and morphometric alterations in the thyroid gland in adult male albino rats after the administration of potassium dichromate for successive 2 months and also to assess the possible protective effect of vitamin C versus melatonin on these changes. Sixty adult male albino rats were randomly divided into four main groups. Group I (The control group). Group II received potassium dichromate (25 mg/kg/day) dissolved in distilled water by intraperitoneal (i.p) injection for 2 months. Group III received the same dose of potassium dichromate with vitamin C (120 mg/kg/day) orally through an intragastric intubation. Group IV received the same dose of potassium dichromate and melatonin (10 mg/kg/day) as an i.p injection. Thyroid gland samples were prepared for light and electron microscopic studies. Potassium dichromate group demonstrated congested blood vessels, follicular hyperplasia, follicular enlargement with degenerated lining cells that were exfoliated in the lumen. The parafollicular cells appeared with darkly stained nuclei. PAS reaction showed weak reaction in the colloid with an abnormal pattern of vacuolization. A highly significant increase in the percentage area of fibrosis was detected in Mallory trichrome sections. Ultrastructurally, follicular cells and parafollicular cells appeared irregular in shape with dark, small heterochromatic nuclei. Small, electron-dense granules in the parafollicular cells were found. Potassium dichromate and vitamin C-treated group III showed partial improvement of the thyroid gland. The PAS reaction showed that nearly all the follicles were more or less similar to those of the control group. A significant decrease in the percentage area of fibrosis in group III was found as compared to those in group II. Potassium dichromate and melatonin-treated group showed that the thyroid gland was nearly similar to that of the control group. Vitamin C and melatonin could partially protect against potassium dichromate induced changes in the thyroid gland and the protective effect of melatonin was better than that of vitamin C.

Repair of Fused Silica Damage Using Selective Femtosecond Laser-Induced Etching

Timely repair of fused silica damage ensures the stable operation of high-power laser systems. In the traditional repair process, the material nearby the damaged area is gradually ablated with CO2 or femtosecond laser. Subsequently, homogenization and residual stress removal are required because of the microcracks and thermal accumulation generated with the ablation. As a result, the repair efficiency is greatly restricted. In this paper, a new method using in-volume, selective femtosecond laser-induced etching to repair the damage of fused silica is proposed. The region irradiated by femtosecond laser becomes more susceptible to the etching solution due to its constitutive characteristics having undergone chemical restructuring. In this way, material nearby the damaged area transparent to the laser radiation is modified locally inside the volume. A femtosecond laser is used to scan the damaged area with a 3D hollow trajectory. The applicable modification of fused silica occurs when the single pulse energy is approximately 2 μJ to 5 μJ, the repetition frequency is approximately 200 kHz to 500 kHz, and the scanning speed is approximately 10 mm/s. Then, the etching solution reacts quickly along the 3D profile of the modified path, and the damaged area is removed as a whole piece. This method can greatly reduce the workload of repair, and the etching process of fused silica is carried out synchronously. So, the etching efficiency is not affected by the number of damage points. In addition, the weak reaction between the etching solution and the substrate could homogenize the interface. It provides an efficient way to repair the surface damage of fused silica.

Se vacancy modulation of centimeter-scale 2D MoSe2 continuous films via Se evaporating temperature

Vacancy defects, often generated during the in situ CVD synthesis, may lead to the deterioration of the physical and chemical properties of 2D atomically thin layers. Due to the weak chemical reactivity of Se, it is still a great challenge to achieve high-quality selenization of large-area 2D transition metal selenides without Se vacancies. In our work, Se evaporating temperature acts as a facile method for the Se-vacancy modulation of centimeter-scale 2D MoSe2 continuous films. It affects the supply of Se source in vapor phase and hence determines the selenization reaction of 2D MoSe2. Not only the Se-vacancy concentration but also layer-thickness distribution could be effectively controlled by changing Se evaporating temperature. The Se-vacancy concentration of the as-selenided MoSe2 continuous films approximately reduces from 5% at 300 ℃ to 0% at 500 ℃. Correspondingly, their layer thicknesses gradually decrease and tend to become an atomically thin layer with centimeter-scale surface coverage. It demonstrates that the sufficient Se supply is crucial for the complete selenization of 2D MoSe2 via elevating Se evaporating temperature. In addition, 2D MoSe2 continuous films with less Se vacancies exhibit better crystalline quality and higher layer-thickness uniformity. Therefore, Se evaporating temperature provides a feasible strategy for optimizing the selenization reaction and modulating the Se-vacancy concentration of 2D transition metal selenides.

BN-Doped Carbon Nanotubes and Nanoribbons as Nonlinear-Optical Functional Materials for Application in Second-Order Nonlinear Optics

Pure carbon-based nanomaterials with good π conjugation and thermal stability, e.g., nanotubes and nanoribbons, have long served as promising conjugated materials for application in second-order nonlinear-optical (NLO) devices but suffer from two inherent structural problems: weak polarity (or even nonpolarity) and high chemical reactivity ascribed to zigzag edge states. In the present work, boron nitride (BN) chains are used to divide carbon nanotubes and nanoribbons, forming a functional block to tune the electronic structure, and thus induce charge redistribution or modify the molecular energy gap for second-order NLO materials or integrated electronic materials. A balance between the electronic kinetic stability and second-order NLO properties is established by structural manipulation. The strong second-order NLO responses in the visible and near-infrared regions make these hybridized carbon-based molecules potential NLO materials for applications in biological nonlinear optics. The application of BN to tune the electronic structure of carbon nanomaterials paves a path for fabricating nanoelectronic and nano-NLO devices.

An Examination of Audio-Visual Simple Reaction Times in Selected Court Games

This research examined the audio-visual simple reaction times in the hands and legs of basketball, handball, and volleyball players. A total of thirty-six (N=36) male athletes randomly participated in this study, among them (n=12) basketball players, (n=12) handball players, and (n=12) volleyball players. The players’ average ages were 22.33±1.15; 22.00±1.41; 21.75±1.22, and they competed at the university level in their respective sports. The timer for Audio-Visual Reaction was used to measure the auditory and visual simple reaction times of the hands and legs in milliseconds. The mean, standard deviation, independent t-test, and one-way ANOVA were used, and the level of significance was set at p&lt;0.05. The F-value of auditory reaction time was 0.21 (&gt; 0.05) in basketball, handball, and volleyball players' strong hand, 0.05 (&gt; 0.05) in weak hand, 1.02 (&gt; 0.05) in strong leg, and 2.23 (&gt; 0.05) in weak leg. Whereas, the strong hand had a visual reaction time of 1.37 (&gt; 0.05), the weak hand had a reaction time of 0.51 (&gt; 0.05), the strong leg had a reaction time of 2.31 (&gt; 0.05), and the weak leg had a reaction time of 0.65 (&gt; 0.05). According to the statistical examination, no significant difference was obtained in auditory and visual reaction times among basketball, handball, and volleyball players with their strong and weak hands and strong and weak legs. Since there was no significant difference in the ANOVA analysis, the reaction times of the limbs (auditory and visual) were compared between each of the two games. The weak leg auditory reaction time was significantly different between basketball and handball players in an independent t-test (t (22) = 2.17, sig. = 0.041 at p 0.05). This study concluded that the auditory and visual simple reaction ability of hands and legs was closer for the three different court games, and a difference was obtained between basketball and handball players concerning weak leg auditory reaction time

Limosilactobacillus walteri sp. nov., a novel probiotic antimicrobial lipopeptide producing bacterium.

A Gram-positive facultative anaerobe, non-spore forming, and non-motile bacterial strain M31 was isolated from faecal contaminated soil. The strain is previously reported to produce a novel antimicrobial lipopeptide and displayed probiotic properties. The strain M31 is catalase negative and fermented D-galactose, D-glucose, esculin, D-maltose, D-lactose, D-melibiose, D-raffinose, D-saccharose (weak reaction), D-xylose (weak reaction), D-ribose (weak reaction), and L-arabinose (weak reaction). The majority of fatty acids were C16:0 (53.9%), C18:0 (26.9%), and C19:0 cyclo ω8c (19.1%). The genome is 2234040bp long with 38.81% GC content. The pairwise ortho average nucleotide identity and digital DNA-DNA hybridisation values of strain M31 with its closest relative species from Lm. reuteri clade and Lm. rudii is below the recommended cut-off of 95% and 70% respectively. Herein, we propose Limosilactobacillus walteri sp. nov. as a novel species of the genus Limosilactobacillus with M31=MTCC 12838=JCM 32759=KCTC 25569.

Taste characteristic and the mechanism of light-colored Maillard reaction products derived from gluten hydrolysate

Light color and savory flavor are difficult to be integrated in ‘Thermal Process Flavoring’ through traditional Maillard reaction. A light-colored seasoning from gluten peptide-glucose system was prepared through gradient temperature-elevating Maillard reaction with extra-added l-cysteine. Greater saltiness and umami enhancement effect of Maillard reaction products (MRPs) were observed from weaker reaction, while lower temperature and longer heating time were conducive to yield kokumi-taste compounds. With the addition of l-cysteine, intensities of fluorescence and UV-VIS absorption of MRPs were weakened. An inhibition of browning and a decrease of α-dicarbonyls concentration caused by l-cysteine were observed. The addition of l-cysteine also led to an increase of peptides below 500 Da (from 53.27 mg/mL to 56.50 mg/mL) and a decrease of cross-linking products in 1–3 kDa, which accounted for superior umami and gentle kokumi attribute of the light-colored products compared with the MRPs without l-cysteine addition.

Preparation of metakaolin-fly ash cenosphere based geopolymer matrices for passive fire protection

In this paper, fly ash cenosphere (FAC) with spherical and hollow structure has been adopted as a pore-forming agent to prepare low density and high strength geopolymer foams. Serial analyses of physical properties, mineral characterization, and thermostability have been employed to investigate the feasibility of metakaolin (MK)-FAC based geopolymer for passive fire protection. FAC addition not only significantly decreases the dry bulk density and thermal conductivity of geopolymer blocks, but also helps to achieve acceptable compressive strength. Meanwhile, FAC addition into geopolymer matrices has brought obviously negative effects on heat transfer and led to the reaction enthalpy rise under high temperature. Owing to the conversion of the amorphous geopolymer gel at the surface to ceramics and excellent thermal insulation performance, the reverse-side temperatures of the geopolymer specimens with FAC addition from 30 to 90 wt% always maintain at about 260 °C until the end of the fire resistance tests. Although weak reactions between alkali activator and FAC have happened and enhanced the bonding between FAC and geopolymer gels, the improvement in physical properties of the MK-FAC based geopolymers would mainly be attributed to the physical characteristics of the FAC. This study could open opportunities to employ MK-FAC geopolymers as alternatives in the application of thermal insulation and fire protection.

Practical Computational Chemistry Course for a Comprehensive Understanding of Organic, Inorganic, and Physical Chemistry: From Molecular Interactions to Chemical Reactions

In all fields of chemistry, it has become essential to use quantum chemical calculations and machine learning for explaining and predicting chemical phenomena. However, it is challenging to apply textbook knowledge to practical research. In this study, we developed teaching material based on computational chemistry to promote the integration of knowledge from all fields of chemistry, including organic, inorganic, and physical chemistry, to bridge the gap between classroom learning and chemistry research. This experimental material, which comprehensively covers weak intermolecular interactions and chemical reactions, is expected to help students conduct purposeful research activities after being assigned to a laboratory.

ABO Genotyping finds more A2 to B kidney transplant opportunities than lectin-based subtyping

ABO compatibility is important for kidney transplantation, with longer waitlist times for blood group B kidney transplant candidates. However, kidneys from non-A1 (eg, A2) subtype donors, which express less A antigen, can be safely transplanted into group B recipients. ABO subtyping is routinely performed using anti-A1 lectin, but DNA-based genotyping is also possible. Here, we compare lectin and genotyping testing. Lectin and genotype subtyping was performed on 554 group A deceased donor samples at 2 transplant laboratories. The findings were supported by 2 additional data sets of 210 group A living kidney donors and 124 samples with unclear lectin testing sent to a reference laboratory. In deceased donors, genotyping found 65% more A2 donors than lectin testing, most with weak lectin reactivity, a finding supported in living donors and samples sent for reference testing. DNA sequencing and flow cytometry showed that the discordances were because of several factors, including transfusion, small variability in A antigen levels, and rare ABO∗A2.06 and ABO∗A2.16 sequences. Although lectin testing is the current standard for transplantation subtyping, genotyping is accurate and could increase A2 kidney transplant opportunities for group B candidates, a difference that should reduce group B wait times and improve transplant equity.

Comparison of Anti-rabies Virus Nucleoprotein IgY Prepared by DNA Immunization and Protein Immunization.

Immunization of egg-laying hens with viral antigens efficiently produces large amounts of virus-specific IgY antibodies from egg yolks. A supply of practical and economical antibodies against the rabies virus is being desired worldwide. We immunized hens with the antigen gene DNA of the rabies virus, purified specific IgY antibodies from the egg yolk, and characterized the immuno-protein chemistry for use as a diagnosis. To prepare specific IgY antibodies against rabies virus nucleoprotein (RV-N) by DNA immunization, laying hens were pre-injected with λ-carrageenan or Freund's complete adjuvant to increase local immune activity (pre-immune stimulation), and then immunized with RV-N recombinant plasmid DNA. RV-N-specific IgY antibodies were prepared from egg yolks of immunized hens. For comparison, conventional protein antigen immunization was also used to induce the production of RV-N-specific IgY antibodies. Laying hens were immunized with an RV-N protein antigen and RV-N-specific IgY was purified from egg yolks. The binding activity against RV-N antigens was examined using IgY samples prepared by DNA (with pre-immune stimulation) and protein immunization. Immunohistochemical staining showed that IgY antibodies prepared by protein immunization strongly detected viral antigens in the brain sections of dogs infected with the virus, whereas IgY antibodies prepared by DNA immunization did not. Enzyme-linked immunosorbent assay was performed using a commercially available rabies vaccine (inactivated virus) treated with 10% formalin and heating (60°C, 30 min and 90°C, 5 min). IgY prepared by DNA immunization had weaker reactivity with denatured antigens and lower antigen concentrations than IgY prepared by protein immunization. These results suggest that it is necessary to develop a DNA immunization method for inducing IgY antibodies against the rabies virus that strongly bind to native and denatured antigens to prepare specific IgYs that can be used for antigen detection in clinical tests.

Behavioral phenomena of depression in adolescence

To study behavioral phenomena of depressive disorders in adolescence. Ninety-five patients, aged 12 to 17 years, with a mixed disorder of emotions and behavior without cognitive impairment and psychotic disorders were examined. Clinical-psychopathological, clinical-follow-up methods, Beck scales, the Spielberger-Khanin scale, Zung and PDO questionnaires, statistical analysis were used. The structure of this syndrome included affective disorders: low mood (n=84 88.4%), loss of interest in studies, everyday life (n=81, 85.3%) and behavioral disorders: manifestation of aggression (n=47, 49.5%), auto-aggression (n=44, 46.3%), suicidal thoughts (n=34, 35.8%), decrease in academic performance (n=35, 36.8%), low motivation for learning, refusal to attend school (n=24, 25.3%). Clinical assessment of the characteristics of behavioral disorders demonstrated the heterogeneity of symptoms, which made it possible to distinguish two groups: psychopathic and anxious behavior. In group I, (n=47, 38.3%) predominated aggression, protest reactions (72.3%), (p<0.001), conflicts with teachers, classmates (87.2%), (p=0.014), addictions (25.5%), (p=0.011). In group II (n=48, 22.9%), there were anxiety symptoms (60.4%, p=0.00015), emotional lability, isolation, with a predominance of schizoid personality traits (62.5%) (χ2=.56, p=0.024, φ=0.242) and with a weak emancipation reaction (78.6%) (χ2=5.16, p=0.04, φ=0.233). Behind the behavioral phenomena of depressive disorders, psychopathic and anxious symptom complexes can occur. These disorders determine the dynamic aspect of the formation of a depressive disorder and occur mainly at the onset of the syndrome. Only long-term follow-up of such patients can answer the question of which nosological form adolescent depression belongs to.

EMOCIONALNE REAKCIJE ADOLESCENATA U NASTAVI

One of the important issues of modern teaching is related to the decline of motivation for school learning. Emotional reactions to cognitive activity play a major role in student development. This paper deals with the role of emotions in educational practice, and the aim of the research is to define and analyze the emotional reactions of high school students to lectures. The sample consisted of 305 students aged between 14 and 19. Data on students’ emotional reactions were collected with the help of the Shabot &amp; Shabot 2009 Self-Assessment of Emotional Reactions Questionnaire. According to the obtained results, students react to lectures with weak and moderate emotional reactions. When it comes to differences between students in relation to gender and age, differences were found in a small number of emotional reactions. The obtained results point to the importance of encourag- ing pleasant emotional reactions in teaching, but also to the need for further research on this important issue.

Advances in Carbon Nanomaterial–Clay Nanocomposites for Diverse Applications

Clay materials are widely used in sheet-type platforms with peculiar characteristics and diverse applications. However, due to some disadvantages—such as weak mechanical strength and low reactivity—they are often subjected to modifications. Such tuning leads to better output than pure clay materials. This review describes some of the clay hybrids in the form of nanocomposites with carbon nanomaterials. Generally, graphene oxide or its derivatives—such as reduced graphene oxide, carbon nanotubes, carbon dots, carbon nanoclusters, and polymeric components—have been utilized so far to make efficient clay composites that have applications such as catalysis, wastewater treatment for toxin removal, cargo delivery, stimulus-responsive advanced tools, optoelectronics, mechanically stable films for filtration, etc. It is interesting to note that nearly all of these applications tend to show the efficacy of modified clay nanocomposites as being significantly greater than that of pure clay, especially in terms of mechanical strength, loading capacity, increased surface area, and tunable functionality. According to the literature, the evidence proves the beneficial effects of these clay nanocomposites with carbon nanomaterials.

Tin disulfide embedded on porous carbon spheres for accelerating polysulfide conversion kinetics toward lithium-sulfur batteries

Lithium-sulfur (Li-S) batteries are considered promising candidates for next-generation advanced energy storage systems due to their high theoretical capacity, low cost and environmental friendliness. However, the severe shuttle effect and weak redox reaction severely restrict the practical application of Li-S batteries. Herein, a functional catalytic material of tin disulfide on porous carbon spheres (SnS2@CS) is designed as a sulfur host and separator modifier for lithium-sulfur batteries. SnS2@CS with high electrical conductivity, high specific surface area and abundant active sites can not only effectively improve the electrochemical activity but also accelerate the capture/diffusion of polysulfides. Theoretical calculations and in situ Raman also demonstrate that SnS2@CS can efficiently adsorb and catalyse the rapid conversion of polysulfides. Based on these advantages, the SnS2@CS-based Li-S battery delivers an excellent reversible capacity of 868 mAh/g at 0.5C (capacity retention of 96 %), a high rate capability of 852 mAh/g at 2C, and a durable cycle life with an ultralow capacity decay rate of 0.029 % per cycle over 1000 cycles at 2C. This work combines the design of sulfur electrodes and the modification of separators, which provides an idea for practical applications of Li-S batteries in the future.

Absorbable suture knots on the supraspinatus tendon prevent adverse effects of nonabsorbable suture knots in a rat model.

To compare the absorbable and nonabsorbable suture knots on the tendon on bone-to-tendon healing during the early phase in a rat rotator cuff tear (RCT) model. Fifty-two male Sprague-Dawley rats (10weeks old; mean weight, 380g) were used in this study, and 51 of them were randomly assigned into three groups: absorbable suture group (ASG, n = 22), nonabsorbable suture group (NSG, n = 22), and sham surgery group (SSG, n = 7), and the remaining rat was used to take surgical pictures. Bilateral supraspinatus tendon tears were created and repaired immediately in ASG and NSG. Three rats from ASG and NSG were killed for Western blot and histological evaluation at 3days, 1week, and 4weeks after surgery. At 4weeks, four rats from each group were killed for biomechanical test, and three rats from SSG were used for histological evaluation. Absorbable suture knots on the tendon completely degraded at 4weeks. However, nonabsorbable suture knots remained intact between the tendon and articular side. ASG showed a stronger inflammatory reaction at 3days and 1week, but a weaker reaction at 4weeks as confirmed by gross observation and Western blot. Besides, ASG showed superior biomechanical properties in terms of maximum load to failure and stiffness at 4weeks. Modified Bonar score revealed superior maturity for tissue healing in ASG to that in NSG at 4weeks. Furthermore, inferior bone-to-tendon interface and weakest link formation were observed in NSG on histologic images. Absorbable suture knots on the tendon contributed to better mechanical properties compared with the nonabsorbable one after rotator cuff repair.

Histochemical characterization of duodenum at early, mid and late prenatal period in goats

Goats [Capra aegagrus hircus (L.)] play a significant role in providing supplementary income and livelihood to humans. The intestine plays a major role in foetus development and growth, and duodenum, as the part of small intestine, is responsible for breakdown of food. As there is not much studies available in literature on this aspect, here, we investigated the developing duodenum of 30 goat embryos/foeti irrespective of breed and sex. The tissues were fixed in 10% neutral buffered formalin and in cold acetone. Different histochemical techniques were applied for the detection and localization of neutral mucopolysaccharides, acid mucopolysaccharides, bound lipids, alkaline phosphatase enzymes, acid phosphatase enzymes, and DNA. The intensity of reactions increased as the age of foeti advanced. The goblet cells of the intestinal gland showed moderate reaction for Periodic acid schiff (PAS) and Acid mucopolysaccharides (AMPs) in the mid prenatal period (Gr. II) and intense to highly intense reaction in the late prenatal period (Gr. III). The cytoplasm of the epithelial cells exhibited negative to mild reaction for bound lipids in Gr. I, mild to moderate in Gr. II and mild to intense reaction in Gr. III. The luminal border of epithelial cells exhibited mild reaction in Gr. I & II, and moderate to intense reaction in Gr. III. The luminal border showed weak acid phosphatase reaction in Gr. I & II, and mild to moderate reaction in Gr. III. The nuclei of the epithelial cells showed mild to moderate Feulgen reaction in Gr. I & II, and intensely positive reaction in Gr. III.

Blood Groups ABO and Rh System Among Paternity and Kinship Cases of Iraqi Medical Legal Directorate

ABO and Rh are the most important blood group systems with various distributions reported for different populations. Traditional ABO blood group and Rh serology is based on the immunoreactivity of antisera with the carbohydrate A, B and H antigens on Red Blood Cells (RBC). Due to its medical importance in relation to different diseases, pursuing a line of investigation on the ABO and Rh blood group systems has been of significance for years. It is well known that these blood group systems are of great importance in blood transfusion and organ transplantation. Furthermore, the susceptibility to several diseases has been associated with the ABO phenotype, but such correlation remains controversial. Progress in the molecular biology of the ABO system has recognized the molecular basis of the red blood cell antigens and has provided a genetic model for ABO polymorphism at the molecular level. The ABH antigens are not primary gene product, but they are the enzymatic reaction product of enzymes called glycosyltransferases. After the ABO system, the Rh (Rhesus) blood group system is regarded as the second most important blood group system, as some of the severe hemolytic transfusion reactions and most hemolytic disease of the fetus and new born (HDFN) cases are associated with antibodies to the Rh group antigens. Objectives: To determine ABO blood group and Rh factor phenotype antigens frequency, distribution, and document among paternity cases of Iraqi Medical Legal Directorate / Clinical Forensic Department / paternity and kinship division. Materials and Methods: The material and methods were used ABO and Rh kits for detection phenotype antigens of this blood types, the principle of test is one step immunological reaction. Total samples (1997) were referred to medical Legal Directorate (MLD). Out of the total participants there were 1815 (98.4%) of samples complete information for inclusion criteria. the sample were used for estimation of phenotypic distribution of ABO, Rh. ABO blood group serology was performed at MLD, Paternity and Kinship Division using commercially available monoclonal Anti-A, Anti-B, reagents according to the national blood bank standard operating procedures. The Method principle is based on antigen antibody reaction (agglutination) some tests were confirmed under microscope examination to see weak reaction. Results: The most common blood group was O (52.3%) and the least common was AB (3.18%).97.7% of the blood participants were Rh Positive and the rest were Rh Negative. Most participants were young adults, representing the age group of 19 – 29. Most participants were male (88.1%). Conclusion: Blood group O and Rh+ factor was dominant in both sexes, Up-to-date knowledge of the distribution of blood types in a local setting is critical to the functioning of any national health service. To date, there has been a lack of data in Iraqi population.

Cutting through the weeds: Evaluation of a novel adsorption with crossmatch cells and elution protocol to sharpen HLA antibody identification by the single antigen bead assay.

The single antigen bead (SAB) assay is the most used test for the identification of HLA specific antibodies pre- and post-transplant. Nevertheless, detection of spurious reactivities remains a recognized assay limitation. In addition, the presence of weak reactivity patterns can complicate unacceptable antigen assignment. This work presents the evaluation of the adsorption with crossmatch cells and elution (AXE) technique, which was designed to help differentiate weak HLA specific antibodies targeting native antigens from spurious and background SAB assay reactivity. The AXE protocol uses selected donor cells to adsorb HLA specific antibodies from sera of interest. Bound antibodies are then eluted off washed cells and identified using the SAB assay. Only antibodies targeting native HLA are adsorbed. Assay evaluation was performed using five cell donors and pooled positive control serum. AXE efficiency was determined by comparing SAB reactivity of adsorbed/eluted antibody to that of the antibodies in unadsorbed sera. A robust efficiency was seen across a wide range of original MFI for donor specific antibodies (DSA). A higher absorption/elution recovery was observed for HLA class I antigens vs. class II. Locus-specific variation was also observed, with high-expression HLA loci (HLA-A/B/DR) providing the best recovery. Importantly, negligible reactivity was detected in the last wash control, confirming that AXE eluates were not contaminated with HLA antibody carry-over. Donor cells incubated with autologous and DSA-containing allogeneic sera showed that AXE selectively adsorbed HLA antibodies in a donor antigen-specific manner. Importantly, antibodies targeting denatured epitopes or other non-HLA antigens were not detected by AXE. AXE was particularly effective at distinguishing weak HLA antibodies from background reactivity. When combined with epitope analysis, AXE enhanced precise identification of antibody-targeted eplets and even facilitated the characterization of a potential novel eplet. Comparison of AXE to flow cytometric crossmatching further revealed that AXE was a more sensitive technique in the detection of weak DSA. Spurious reactivities on the current SAB assay have a deleterious impact on the assignment of clinically relevant HLA specificities. The AXE protocol is a novel test that enables users to interrogate reactive patterns of interest and discriminate HLA specific antibodies from spurious reactivity.