Evaluation of vacuum infiltration vitrification and cryo-mesh cryopreservation techniques with Arabidopsis thaliana shoot tips

BACKGROUND

Novel cryo-techniques are continuously being developed that may better improve cryogenic survival in plants, with the aim of reducing exposure times to otherwise toxic cryoprotective agents whilst maximising regeneration rates.

OBJECTIVE

This study used cryo-mesh and vacuum infiltration vitrification with two vitrification solutions (PVS2 and PVS3) to develop an optimised cryopreservation protocol for Arabidopsis thaliana.

MATERIALS AND METHODS

Shoot tips from 10-day old seedlings of wild type A. thaliana were cryopreserved using either vacuum infiltration vitrification or the cryo-mesh technique. Shoot tips were treated for up to 60 min in increments of 10 min with PVS2 and PVS3, and for an additional 180 and 300 min incubation for cryo-mesh prior to exposure to liquid nitrogen.

RESULTS

Both methods resulted in very high regeneration rates, but which decreased after longer exposure to the vitrification solutions. The highest regeneration rate for vacuum-infiltration vitrification was attained after only 30 min incubation in PVS2 (92.5%) and 50 min incubation in PVS3 (93.6%). In the case of cryo-mesh the highest regeneration was observed after 180 min incubation in either PVS2 (100%) or PVS3 (92.2%).

CONCLUSION

Vacuum-infiltration vitrification is more effective than cryo-mesh by reducing exposure times to cryoprotective solutions whilst achieving very high regeneration rates of shoot tips of A. thaliana. https://doi.org/10.54680/fr22610110712.

Acute hemolytic transfusion reaction caused by anti-Yta

Many patients with anti-Yt^a receive multiple transfusions of Yt(a+) red blood cells (RBCs) with no ill effects. However, anti-Yt^a has been implicated in hemolytic transfusion reactions. Antibody identification typically determines specificity of antibodies and their clinical significance to justify blood requirements for antigen-negative blood when clinically significant antibodies are involved. Occasionally, specificity of antibody is of variable significance. Variability in clinical significance is a characteristic of anti-Yt^a that may affect the clinical management of such patients. This case reports the outcome of an incompatible transfusion in an 83-year-old female patient with anti-Yt^a, -D, -C, -Le^ab, and -HI who was admitted to the hospital for a severe urinary tract hemorrhage and fever. The patient was transfused with 1 crossmatch-incompatible group A, Yt(a+), D-, C-, E-, S- RBC unit in an emergency medical event. During that time, the patient exhibited chills, shivering, and tachycardia. Decreases in hemoglobin and hematocrit were noted. Laboratory parameters for hemolysis, such as total bilirubin, direct bilirubin, and lactate dehydrogenase, were increased. Based on clinical and laboratory evaluation, it was concluded that the patient had an acute hemolytic transfusion reaction caused by anti-Yt^a. The patient was successfully treated with antipyretics, antihistamines, and corticosteroids. Urinary tract hemorrhaging was stopped. Anemia was additionally improved with parenteral iron supplementation, and further transfusion was not required. Immunohematology 2021;37:13-17. Many patients with anti-Yt^a receive multiple transfusions of Yt(a+) red blood cells (RBCs) with no ill effects. However, anti-Yt^a has been implicated in hemolytic transfusion reactions. Antibody identification typically determines specificity of antibodies and their clinical significance to justify blood requirements for antigen-negative blood when clinically significant antibodies are involved. Occasionally, specificity of antibody is of variable significance. Variability in clinical significance is a characteristic of anti-Yt^a that may affect the clinical management of such patients. This case reports the outcome of an incompatible transfusion in an 83-year-old female patient with anti-Yt^a, -D, -C, -Le^ab, and -HI who was admitted to the hospital for a severe urinary tract hemorrhage and fever. The patient was transfused with 1 crossmatch-incompatible group A, Yt(a+), D–, C–, E–, S– RBC unit in an emergency medical event. During that time, the patient exhibited chills, shivering, and tachycardia. Decreases in hemoglobin and hematocrit were noted. Laboratory parameters for hemolysis, such as total bilirubin, direct bilirubin, and lactate dehydrogenase, were increased. Based on clinical and laboratory evaluation, it was concluded that the patient had an acute hemolytic transfusion reaction caused by anti-Yt^a. The patient was successfully treated with antipyretics, antihistamines, and corticosteroids. Urinary tract hemorrhaging was stopped. Anemia was additionally improved with parenteral iron supplementation, and further transfusion was not required. Immunohematology 2021;37:13–17.

Circulating IL-10 Levels in Carotid Artery Disease

Carotid atherosclerosis may be associated with neurosymptoms including cerebral infarction. IL-10 exerts atheroprotective effects, but its role in carotid disease is not fully defined. We aimed to investigate serum IL-10 levels in patients undergoing endarterectomy and their relation to the degree of carotid stenosis, plaque types and neurosymptoms.

Two hundred consecutive patients with atherosclerotic carotid stenosis and 29 healthy controls were enrolled in this study. Plaque types were classified according to AHA criteria. Serum IL-10 levels were determined by ELISA.

Patients undergoing endarterectomy had significantly higher circulating IL-10 levels (18.7 ± 3.2 pg/ml) in comparison with healthy controls (7.2 ± 1.8pg/ml; P =0.0001) and IL- 10 has good discriminatory efficacy between these two groups (ROC curve, AUC = 0.723, P=0.0001). Patients with < 70% and those with > 70% of carotid stenosis did not differ in terms of age, sex, cardiovascular risk factors except hypertension, neurosymptoms and AHA plaque types. Circulating IL-10 levels differed significantly among patients with different carotid plaque types (P = 0.002). Patients with uncomplicated plaques had significantly higher serum levels of IL-10 (23.0 ± 6.1 pg/ml) compared to those with complicated plaques (13.0 ±1.4 pg/ml, P=0.035) and IL-10 can differentiate patients between these two groups (ROC curve, AUC = 0.413, P= 0.035).

Our findings reveal an important role for IL-10 in carotid atherosclerosis. IL-10 might be a potential biomarker in discriminating patients with carotid disease from healthy controls. Decreased serum levels of IL-10 are related to complicated carotid plaques.

Serum parathyroid hormone is associated with increased cortical porosity of the inner transitional zone at the proximal femur in postmenopausal women: the Tromsø Study

Serum parathyroid hormone (PTH) was associated with increased bone turnover markers and cortical porosity of the inner transitional zone at the proximal femur. These results suggest that PTH through increased intracortical bone turnover leads to trabecularisation of inner cortical bone in postmenopausal women.

INTRODUCTION

Vitamin D deficiency leads to secondary hyperparathyroidism and increased risk for fractures, whereas its association with cortical porosity is less clear. We tested (i) whether serum 25-hydroxyvitamin D (25(OH)D) and PTH were associated with cortical porosity and (ii) whether the associations of 25(OH)D) and PTH with fracture risk are dependent on cortical porosity.

METHODS

This case-control study included 211 postmenopausal women, 54-94 years old, with prevalent fractures and 232 controls from the Tromsø Study. Serum 25(OH)D, PTH, and bone turnover markers (procollagen type I N-terminal propeptide [PINP] and C-terminal cross-linking telopeptide of type I collagen [CTX]) were measured. Femoral subtrochanteric cortical and trabecular parameters were quantified using computed tomography, and femoral neck areal bone mineral density (FN aBMD) was quantified using dual-energy X-ray absorptiometry.

RESULTS

Compared with controls, fracture cases exhibited reduced serum 25(OH)D and increased PTH, PINP, and CTX, increased femoral subtrochanteric cortical porosity, and reduced cortical thickness and FN aBMD (all, p < 0.05). Serum 25(OH)D was not associated with cortical parameters (all, p > 0.10). PTH was associated with increased PINP, CTX, and cortical porosity of the inner transitional zone and reduced trabecular bone volume/tissue volume and FN aBMD (p ranging from 0.003 to 0.054). Decreasing 25(OH)D and increasing PTH were associated with increased odds for fractures, independent of age, height, weight, calcium supplementation, serum calcium, cortical porosity, and thickness.

CONCLUSIONS

These data suggest that serum PTH, not 25(OH)D, is associated with increased intracortical bone turnover resulting in trabecularisation of the inner cortical bone; nevertheless, decreasing 25(OH)D) and increasing PTH are associated with fracture risk, independent of cortical porosity and thickness.

Peptides with antimicrobial and anti-inflammatory activities that have therapeutic potential for treatment of acne vulgaris

The pathogenesis of acne vulgaris is multifactorial involving infection of the pilosebaceous unit with Propionibacterium acnes and a cytokine-mediated inflammatory response. Five frog skin-derived antimicrobial peptides ([D4k]ascaphin-8, [G4K]XT-7, [T5k]temporin-DRa, brevinin-2GU, and B2RP-ERa), chosen for their low hemolytic activity against human erythrocytes, were assessed for their effects on the growth of clinical isolates of P. acnes and on the release of pro-inflammatory and anti-inflammatory cytokines from peripheral blood mononuclear (PBM) cells. All peptides inhibited the growth of P. acnes with the highest potency exhibited by [D4k]ascaphin-8 (minimum inhibitory concentration, MIC=3-12.5 μM). Release of TNF-α from concanavalin A (ConA)-stimulated PBM cells was significantly reduced by [D4k]ascaphin-8, [G4K]XT-7, brevinin-2GU, and B2RP-ERa (1 and 20 μg/ml) and by [T5k]temporin-DRa (20 μg/ml). Release of IFN-γ from unstimulated PBM cells was significantly reduced by [D4k]ascaphin-8 and brevinin-2GU (1 and 20 μg/ml). No peptide showed significant effects on Il-17 release. Release of the anti-inflammatory cytokines TGF-β, IL-4, and IL-10 from both unstimulated and ConA-treated PBM cells was significantly increased by [T5k]temporin-DRa and B2RP-ERa (1 and 20μg/ml). The potent activities of [D4k]ascaphin-8 and [T5k]temporin-DRa in inhibiting the growth of P. acnes and the release of pro-inflammatory cytokines, and in stimulating the release of anti-inflammatory cytokines suggest a possible therapeutic role in the treatment of acne vulgaris.

ST2 deficiency enhances the severity of Th1/Th-17 mediated inflammation (83.27)

ST2 selectively and stably expressed on the surface of T-helper 2 (Th2) but not Th-1 cells is a ligand for recently identified Interleukin-33 (IL-33). We have studied the susceptibility to and severity of the two T cell mediated inflammatory process: multiple low dose streptozotocin induced diabetes and Con-A induced hepatitis, in ST2 deficient (ST2-/-) and “wild-type: BALB/C mice. After diabetes induction (40mg STZ/kg b.w. for 5 days) ST2-/- mice developed glycemia and glycosuria. β cell loss and intra-islet mononuclear infiltrates while “wild type” mice did not develop any biochemical signs and histology revealed only peri-insulitis. When injected with Con-A (12 mg/kg b.w) ST2-/- mice developed significantly enhanced hepatitis as evaluated by liver function test 8 and 24 hours after induction and quantitative analysis of the hepatocytes necrosis. Analysis of cellular make up of the pancreatic lymph nodes and pancreata (in diabetes) and liver infiltrating cells (in ConA induced hepatitis) and their cytokines content by FACS analysis and cytokine expression by RT-PCR revealed the enhanced infiltration of Th-1 and Th-17 cells and higher content and expression of proinflammatory cytokines: IFN-γ, IL-17 and TNF. We therefore concluded that attenuation of IL-33-ST2 axis facilitates the induction of Th-1/Th-17 mediated inflammatory autoimmunity.

Association of TCF7L2 polymorphism with diabetes mellitus, metabolic syndrome, and markers of beta cell function and insulin resistance in a population-based sample of Emirati subjects

AIMS

The prevalence of type 2 diabetes mellitus (DM) among Emirati subjects is one of the highest in the world. This has been attributed to rising prevalence of obesity acting on genetically susceptible individuals. We analyzed the associations between TCF7L2 polymorphism and DM, metabolic syndrome, and markers of beta cell function and insulin resistance in a population-based sample of Emirati subjects.

METHODS

We genotyped the two TCF7L2 single nucleotide polymorphisms (SNPs) rs12255372 and rs7903146 in 368 adult subjects. Homeostatic model assessment (HOMA) was used to assess beta cell function (HOMA2-%B) and insulin resistance (HOMA2-IR). The SNP genotypes were analyzed against disease stage [normal glucose=0 (n=188), pre-diabetes=1 (n=85), and DM=2 (n=95)] and against clinical and biochemical measures. Age and sex were included as covariates in all association analyses. Additional adjustments were made for body mass index (BMI) and waist circumference in several analyses.

RESULTS

Diabetes disease stage was marginally significantly associated with the frequency of the T variant at rs12255372 (p=0.057; adjusted p=0.017) but not at rs7903146 (p=0.5; adjusted p=0.2). Comparison between subjects with normal glucose and the combined DM/pre-diabetes showed a significant association with rs12255372 (OR 1.47, CI 1.04-2.08; p=0.03) but not with rs7903146 (OR 1.16, CI 0.81-1.64; p=0.4). We found no association with metabolic syndrome, or with insulin and glucose levels, HOMA2-%B or HOMA2-IR. The age-standardized prevalence rate for metabolic syndrome was 43.9% in men and 42.1% in women.

CONCLUSION

These data suggest that TCF7L2 variants are associated with increased risk for DM in Emirati subjects. We also demonstrate a high prevalence of the metabolic syndrome in this population.

Prevalence of diabetes mellitus and its complications in a population-based sample in Al Ain, United Arab Emirates

AIMS

To determine the prevalence of diabetes mellitus (DM) and its complications in the adult population of the United Arab Emirates (UAE) and assess the degree of metabolic control in subjects with diagnosed DM.

METHODS

A random sample of houses of Emirati citizens living in Al Ain, UAE was surveyed. Fasting blood glucose was determined by glucose meter and an oral glucose tolerance test (OGTT) was conducted if blood sugar was <7 mmol/l. DM was defined according to the WHO criteria. Pre-diabetes status was based on fasting venous blood glucose concentration of 5.6-6.9 mmol/l or 2h post-OGTT venous blood glucose level of 7.8-11.0 mmol/l.

RESULTS

There were 2455 adults (>18) living in the 452 surveyed houses of which 10.2% reported having the diagnosis of DM. A total of 373 men and non-pregnant women underwent testing, and after adjustment for factors affecting participation probability the prevalence of diagnosed DM, undiagnosed DM and pre-diabetes was 10.5, 6.6 and 20.2%, respectively. Age-standardized rates for DM (diagnosed and undiagnosed) and pre-diabetes among 30-64 years old were 29.0 and 24.2%, respectively. Logistic regression analysis showed that only age and body mass index (BMI) were significantly independently related to undiagnosed DM. In patients with diagnosed DM, the prevalence rates for retinopathy, neuropathy, nephropathy, peripheral vascular disease and coronary heart disease were 54.2, 34.7, 40.8, 11.1 and 10.5%, respectively. A significant proportion of subjects with undiagnosed DM and pre-diabetes also had micro- and macro-vascular complications. The proportion of subjects with diagnosed DM who achieved internationally recognized targets for HbA1c (<7%), LDL-C (<2.6 mmol/l) and blood pressure (<130/80 mmHg) was 33.3, 30.8 and 42.1%, respectively.

CONCLUSION

This study confirms the previously reported high prevalence of DM in the UAE. Diabetic complications were highly prevalent among subjects with diagnosed and undiagnosed DM. Metabolic control was suboptimal in most subjects with diagnosed DM. Greater efforts are urgently needed to screen early and effectively treat DM in the UAE in order to prevent long-term complications.

Induction of immunoglobulin G1, interleukin-6 and interleukin-10 by Taenia crassiceps metacestode carbohydrates

T helper type 2 (Th2) -polarized immune responses are characteristically dominant in helminth infections. Two murine models that show a Th1 to Th2 polarization with infection progression are those of Schistosoma mansoni and Taenia crassiceps. In both, an early Th1 response is replaced by a late Th2 response. We report that the nucleic acid-, protein- and lipid-free carbohydrate fraction of T. crassiceps metacestodes (denoted T-CHO) possesses Th2-like immunomodulatory activity. Immunization of two strains of rats (Dark Agouti and Albino Oxford) and BALB/c mice with chicken albumin in the presence of T-CHO resulted in selective enhancement of immunoglobulin G1 (IgG1) antibodies, considered to be associated with Th2 responses in both rats and mice. Interleukin-6 (IL-6) followed by IL-10 were the dominant cytokines detected in in vitro cultures of mouse spleen cells stimulated with T-CHO. IL-4 and IL-5 were not detected in these culture supernates. Furthermore, Taenia carbohydrates were mitogenic to spleen cells, activated serine phosphorylation of proteins and up-regulated the expression of the anti-apoptotic protein, Bcl-2. When mouse spleen cells were cultured in the presence of Taenia carbohydrates, a concentration-dependent down-regulation of IL-2 and an overlapping up-regulation of IL-6 secretion were seen.

Erythroid-committed progenitors and spleen colony-forming cells in adult thymus-deprived mice

The effect of thymus deprivation on spleen colony-forming unit (CFU-s), the erythroid repopulating ability (ERA) of bone marrow cells, erythropoietin-responsive cells (ERC) and the erythroid colony-forming unit (CFU-e) was investigated in adult mice. Female CBA mice, thymectomized at the age of 6 weeks, were used for the experiments at 3 to 5 weeks later (Tx). Thymectomized, lethally irradiated and bone marrow cell-reconstituted mice (TIR) were used 2 months after reconstitution. A decrease of ERA was found if Tx animals were used as recipients of normal or Tx bone marrow cells. Estimated values of ERC and number of CFU-e-derived colonies in the bone marrow and spleen in response to 3 units of erythropoietin (Ep) were lower in Tx than in control polycythaemic mice. In TIR animals, a lower number of femoral CFU-s was found, but the ERA and ERC values were not affected. However, in response to 3 units of Ep, the number of CFU-e-derived colonies differed in the bone marrow of TIR animals as compared to the values found in normal, reconstituted mice.

Immunologic Tolerance to Heterologous Immunoglobulin: Its Relation to In Vitro Filtration by Macrophages

The cellular and molecular basis for the difference in ability of BGG to induce tolerance in BALB/c and DBA/2 mice has been examined by in vitro biofiltration. It was found that incubation with the adherent cells from BALB/c but not DBA/2 spleens could remove the material from BGG which inhibited tolerance induction in BALB/c mice. This material was shown to represent only a trace component in BGG, was present in only certain commercial batches of BGG, and was apparently unrelated to the presence of aggregates or endotoxin.

Immunologic tolerance to heterologous immunoglobulin: its relation to in vitro filtration by macrophages

The cellular and molecular basis for the difference in ability of BCG to induce tolerance in BALB/c and DBA/2 mice has been examined by in vitro biofiltration. It was found that incubation with the adherent cells from BALB/c but not DBA/2 spleens could remove the material from BGG which inhibited tolerance induction in BALB/c mice. This material was shown to represent only a trace component in BGG, was present in only certain commercial batches of BGG, and was apparently unrelated to the presence of aggregates or endotoxin.

The Cutaneous Basophil Response to Phytohemagglutinin in Chickens

A cellular infiltrate rich in basophils was observed in chickens in skin sites injected locally with the mitogen PHA. These infiltrating metachromatically granulated cells exhibited features common to mast cells of some species (monolobed nucleus), but also resembled basophils of other species in that they circulated in the blood, and they responded to the PHA mitogen by infiltrating skin test sites. Previous literature suggests that the chicken has a single metachromatic granulated cell and our data support this notion. PHA, a known T cell mitogen, may act by causing the stimulated T lymphocyte to produce a lymphokine that is responsible for the attraction of basophils to the test site.

The cutaneous basophil response to phytohemagglutinin in chickens

A cellular infiltrate rich in basophils was observed in chickens in skin sites injected locally with the mitogen PHA. These infiltrating metachromatically granulated cells exhibited features common to mast cells of some species (monolobed nucleus), but also resembled basophils of other species in that they circulated in the blood, and they responded to the PHA mitogen by infiltrating skin test sites. Previous literature suggests that the chicken has a single metachromatic granulated cell and our data support this notion. PHA, a known T cell mitogen, may act by causing the stimulated T lymphocyte to produce a lymphokine that is responsible for the attraction of basophils to the test site.