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.

A Prospective Diet-Wide Association Study for Risk of Colorectal Cancer in EPIC

BACKGROUND & AIMS

Evidence regarding the association of dietary exposures with colorectal cancer (CRC) risk is not consistent with a few exceptions. Therefore, we conducted a diet-wide association study (DWAS) in the European Prospective Investigation into Cancer and Nutrition (EPIC) to evaluate the associations between several dietary exposures with CRC risk.

METHODS

The association of 92 food and nutrient intakes with CRC risk was assessed in 386,792 participants, 5069 of whom developed incident CRC. Correction for multiple comparisons was performed using the false discovery rate, and emerging associations were examined in the Netherlands Cohort Study (NLCS). Multiplicative gene-nutrient interactions were also tested in EPIC based on known CRC-associated loci.

RESULTS

In EPIC, alcohol, liquor/spirits, wine, beer/cider, soft drinks, and pork were positively associated with CRC, whereas milk, cheese, calcium, phosphorus, magnesium, potassium, riboflavin, vitamin B6, beta carotene, fruit, fiber, nonwhite bread, banana, and total protein intakes were inversely associated. Of these 20 associations, 13 were replicated in the NLCS, for which a meta-analysis was performed, namely alcohol (summary hazard ratio [HR] per 1-SD increment in intake: 1.07; 95% confidence interval [CI], 1.04-1.09), liquor/spirits (HR per 1-SD increment in intake, 1.04; 95% CI, 1.02-1.06), wine (HR per 1-SD increment in intake, 1.04; 95% CI, 1.02-1.07), beer/cider (HR per 1-SD increment in intake, 1.06; 95% CI, 1.04-1.08), milk (HR per 1-SD increment in intake, 0.95; 95% CI, 0.93-0.98), cheese (HR per 1-SD increment in intake, 0.96; 95% CI, 0.94-0.99), calcium (HR per 1-SD increment in intake, 0.93; 95% CI, 0.90-0.95), phosphorus (HR per 1-SD increment in intake, 0.92; 95% CI, 0.90-0.95), magnesium (HR per 1-SD increment in intake, 0.95; 95% CI, 0.92-0.98), potassium (HR per 1-SD increment in intake, 0.96; 95% CI, 0.94-0.99), riboflavin (HR per 1-SD increment in intake, 0.94; 95% CI, 0.92-0.97), beta carotene (HR per 1-SD increment in intake, 0.96; 95% CI, 0.93-0.98), and total protein (HR per 1-SD increment in intake, 0.94; 95% CI, 0.92-0.97). None of the gene-nutrient interactions were significant after adjustment for multiple comparisons.

CONCLUSIONS

Our findings confirm a positive association for alcohol and an inverse association for dairy products and calcium with CRC risk, and also suggest a lower risk at higher dietary intakes of phosphorus, magnesium, potassium, riboflavin, beta carotene, and total protein.

Dietary intake of trans fatty acids and breast cancer risk in 9 European countries

BACKGROUND

Trans fatty acids (TFAs) have been hypothesised to influence breast cancer risk. However, relatively few prospective studies have examined this relationship, and well-powered analyses according to hormone receptor-defined molecular subtypes, menopausal status, and body size have rarely been conducted.

METHODS

In the European Prospective Investigation into Cancer and Nutrition (EPIC), we investigated the associations between dietary intakes of TFAs (industrial trans fatty acids [ITFAs] and ruminant trans fatty acids [RTFAs]) and breast cancer risk among 318,607 women. Multivariable hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazards models, adjusted for other breast cancer risk factors.

RESULTS

After a median follow-up of 8.1 years, 13,241 breast cancer cases occurred. In the multivariable-adjusted model, higher total ITFA intake was associated with elevated breast cancer risk (HR for highest vs lowest quintile, 1.14, 95% CI 1.06-1.23; P trend = 0.001). A similar positive association was found between intake of elaidic acid, the predominant ITFA, and breast cancer risk (HR for highest vs lowest quintile, 1.14, 95% CI 1.06-1.23; P trend = 0.001). Intake of total RTFAs was also associated with higher breast cancer risk (HR for highest vs lowest quintile, 1.09, 95% CI 1.01-1.17; P trend = 0.015). For individual RTFAs, we found positive associations with breast cancer risk for dietary intakes of two strongly correlated fatty acids (Spearman correlation r = 0.77), conjugated linoleic acid (HR for highest vs lowest quintile, 1.11, 95% CI 1.03-1.20; P trend = 0.001) and palmitelaidic acid (HR for highest vs lowest quintile, 1.08, 95% CI 1.01-1.16; P trend = 0.028). Similar associations were found for total ITFAs and RTFAs with breast cancer risk according to menopausal status, body mass index, and breast cancer subtypes.

CONCLUSIONS

These results support the hypothesis that higher dietary intakes of ITFAs, in particular elaidic acid, are associated with elevated breast cancer risk. Due to the high correlation between conjugated linoleic acid and palmitelaidic acid, we were unable to disentangle the positive associations found for these fatty acids with breast cancer risk. Further mechanistic studies are needed to identify biological pathways that may underlie these associations.

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.

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.

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 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.