Effects of Respiratory and Cardiac Motion on Dose to the Left Anterior Descending Artery in Patients Undergoing Radiation Therapy for Locally Advanced Lung Cancer

PURPOSE/OBJECTIVE(S)

Radiation dose to the left anterior descending artery (LAD) appears to be an independent predictor of major cardiac events and all-cause mortality following radiation therapy (RT) for lung cancer. In this study, we characterize the dosimetric effects of respiratory (RM) and cardiac (CM) motion on LAD.

MATERIALS/METHODS

Ten patients with stage IIIA-IVA lung cancer received cine MRIs (25 phases) at expiration which were used to evaluate the CM, and 4D CT scans for the evaluation of RM. Following registration of the expiration images of 4D CTs with MRIs, RT dose was transferred from planning CT datasets to all phases of 4D CTs and cine MRIs. LAD was manually contoured on all scans. The contours from each 4D phase represent LADs over multiple cardiac cycles, thus they are referred to as cLAD from here on. Displacements and dose variations of cLAD between exhale/inhale on 4D CTs and of LAD between systolic and diastolic phases on cine MRIs were analyzed, and paired t-tests were performed to assess the significance of the differences observed.

RESULTS

The following metrics are reported averaged over all patients. Clinical treatment planning CT metrics and doses: Mean dose, max dose, V5 Gy and V15 Gy were 15.0 (±11.3) Gy, 31.1 (±22.1) Gy, 53 (±33)%, 35 (±30)%. The cLAD metrics and dose variations due to respiratory motion (between exhale and inhale): RM amplitude was 0.3±0.2cm (RL 0.3 ± 0.1 cm, AP 0.2 ± 0.2 cm, SI 0.3 ± 0.2 cm). The variations in mean dose, max dose, V5 and V15 were 4.0 (±4.0) Gy, 1.6 (±1.5) Gy, 4.4 (±3.4)%, 4.0 (±3.4)%. Mean, max, V5 Gy and V15 Gy increased or remained unchanged with expiration in 8, 9, 5 and 5 patients, respectively. LAD metrics and dose variations due to cardiac motion (between systole and diastole): CM amplitude was 0.2 ± 0.1 cm (RL 0.2 ± 0.1 cm, AP 0.2 ± 0.1 cm, SI 0.3 ± 0.1 cm). The variations in mean dose, max dose, V5 and V15 were 1.7 (±1.4) Gy, 1.2 (±0.9) Gy, 5.2 (± 6.7)%, 4.6 (± 4.0)%. Mean, max, V5 Gy and V15 Gy increased or remained unchanged with diastole in 7, 7, 8 and 8 patients respectively. Statistical significance: The differences in displacement and dose between respiration and cardiac motion were not statistically significant.

CONCLUSION

Respiratory and cardiac-induced physiological variations of the LAD position have dosimetric consequences comparable in magnitude. Expiration and diastole lead to increased LAD doses. This underscores the importance of considering both the respiratory and the cardiac motion when motion management techniques are considered. 4D CTs inherently include the cardiac motion. However, if breath-hold is used for respiratory motion mitigation, CM might not be captured appropriately due to short tube rotation times. In this case, understanding CM characteristics is important for more accurate assessment of LAD dose.

Immunological and bacteriological quality of fresh cow colostrum and passive immunity transfer in selected dairy farms in Fars, Iran

Background

The quality of colostrum is affected by IgG level and microbial load.

Aims

The quality of colostrum used in feeding dairy calves and passive immunity transfer in selected dairy farms in Fars province, Iran was investigated.

Methods

A total of 75 colostrum and neonatal blood samples were collected from 11 herds. The immunological quality of colostrum was assessed using a Brix digital refractometer. The bacteriological quality was assessed by performing total plate count (TPC), total coliform count (TCC), spore-former count, fungi count, and species-specific PCR assay to detect some bacterial species.

Results

The mean Brix of colostrum samples was 25.4% and 72% of the samples had a Brix score ≥22%. The mean serum Brix and the prevalence of failure of passive transfer (FPT) were 10% and 4%, respectively. The mean TPC, TCC, spore-former count, and fungi count were 3.6 × 10⁵, 2.8 × 10⁴, 3.2 × 10⁴, and 1.1 × 10⁴ CFU/ml, respectively. The results showed that 50, 5.9, and 4% of colostrum samples were positive for Staphylococcus spp., Salmonella spp. and Maycobacterium paratuberculosis, respectively. There was no evidence of contamination with Brucella spp., Corynebacterium bovis and Mycoplasma bovis.

Conclusion

Considering all colostrum quality indicators comprehensively, only 37.3% of the studied samples met the industry standard. A large number of calves were at risk of receiving poor quality colostrum, especially in terms of microbial contamination. Further researches are needed to evaluate the colostrum management and the effect of bacterial contamination of colostrum on the health of neonate calves in this region.

Compromised liver functions during the breeding period of clinically healthy Holstein cows

BACKGROUND

The sub-clinical carry-over effects of post-partum (PP) conditions and the problems independent of parturition may affect the cows' performance during the breeding period.

AIMS

It was hypothesized that some mid-lactation cows may have compromised liver functions and calculating liver activity index (LAI; -1.5 to +1.5) may be helpful in detecting such conditions.

METHODS

Plasma lipid and protein profiles, retinol and ceruloplasmin were measured in 37 Holstein cows on days 60, 90, and 120 PP. Liver activity index was calculated using the measures of cholesterol, albumin and retinol. The results were interpreted using some health and performance indices.

RESULTS

The mean LAI was 0.00 ± 0.61. Sixteen cows (45.7%) were LAI‾ and 19 cows (54.3%) were LAI⁺. In LAI⁺ cows the concentrations of cholesterol and albumin were unchanged, but in LAI‾ cows both of them increased through the study (P<0.05). Greater concentrations of low density lipoproteins (LDL) (P<0.01) and lower concentrations of γ- and total globulins (P<0.05; day 60) were detected in LAI⁺ cows. Ceruloplasmin was not different between the LAI groups with the highest level on day 90. Cholesterol had the strongest and the most repeated correlations with LAI during the study. The correlation of albumin with LAI faded on day 120 and vitamin A had a relationship only on day 60 PP. Triglycerides (TGs), very low density lipoproteins (VLDL) (day 60) and LDL (days 60 and 90) had positive correlations with LAI. All globulin fractions showed negative correlations with LAI on day 60. Seventy percent of the cows without endometritis (day 30 PP) and 33% of the infected cows were LAI⁺ during the breeding period. About 79% of the cows with body condition score (BCS) loss ≤0.75 (day 60) and 38% of the cows with BCS loss >0.75 were LAI⁺ during the breeding period.

CONCLUSION

Compromised liver functions may exist in dairy cows during the breeding period and may be detected by calculating LAI. The relationship of LAI during the progressed lactation with herd's performance needs to be investigated.

The effects of post-partum drops in body condition on indices of energy metabolism in mid-lactation Holstein cows

BACKGROUND

Evaluation of energy metabolism indices in mid-lactation Holstein cows is critical to monitor health status. Aims: The objective of this study was to assess the effects of low (≤0.75) vs. high (>0.75) drops in body condition score (BCS) until day 60 post-partum on energy metabolism indices during mid-lactation in Holstein cows.

METHODS

Twenty-eight Holstein cows were included in the study from the day of calving to day 120 of lactation. Whole blood samples were taken on 60, 90, and 120 days in milk (DIM). Serum was analyzed for insulin, glucose, non-esterified fatty acids (NEFA) and beta-hydroxybutyrate (BHB) levels.

RESULTS

In cows with low BCS drop (LoD group), insulin did not change significantly through days 60 to 120 of lactation, but increased in high drop cows (HiD group) (P<0.001). Glucose concentrations decreased linearly in the LoD cows (P=0.039) and showed a quadratic increase in the HiD group on day 90 (P=0.028). Concentrations of non-esterified fatty acids showed both linear (P=0.04) and quadratic (P=0.002) changes in the HiD group. The HiD cows had significantly higher concentrations of insulin on day 120 (P=0.017) compared to the LoD group. Glucose concentration was lower (P<0.01) in HiD cows on 60 DIM. The concentration of non-esterified fatty acids was higher in HiD cows on day 90 (P<0.01). Surrogate indices of insulin resistance (calculated based on the concentrations of the measured metabolites) were different between the groups on day 90, indicating decreased insulin sensitivity in the HiD cows.

CONCLUSION

Greater depletion of body reserves during early lactation may result in some inconsistencies in energy metabolism during mid-lactation periods. Controlling BCS loss during early lactation may help alleviate such alterations possibly through modifying insulin sensitivity of the tissues.

A field study on glucose, non-esterified fatty acids, beta-hydroxybutyrate and thyroid hormones in dairy cows during the breeding period in Fars province, Iran

BACKGROUND

It was hypothesized that under apparently good management practices in dairy farms, some cows may not be metabolically perfect during the breeding period and this may affect their performance.

AIMS

This study was conducted to assess probable metabolic drawbacks in mid-lactation dairy cows affecting their performance.

METHODS

Thirty-seven clinically healthy Holstein cows were assessed for plasma concentrations of glucose, non-esterified fatty acids (NEFA), beta-hydroxybutyrate (BHB), thyroxin (T4), and tri-iodothyronine (T3) on days 60, 90 and 120 of lactation. The relationships of the measured analytes with some performance indices were also studied.

RESULTS

Continuous declines in plasma glucose (within reference values; P<0.006), T4 (P<0.001) and T3 (0.003) were found during the study. Non-esterified fatty acids showed relatively high levels through the study with a rise at day 90 (P<0.041). Beta-hydroxybutyrate concentrations did not change significantly (P>0.05) but were higher than those reported by others in mid-lactation cows. By progress in lactation 27% of cows had glucose concentrations <2.5 mmol/L, 62% had NEFA concentrations >0.40 mmol/L and 13.5% had BHB levels above 1200 µmol/L, which are the threshold levels of peri- and post-parturient problems. Milk production had negative correlations with glucose and T4 while the correlation was positive with NEFA. The interval between calving to the 1st heat had positive correlations with BHB concentrations. The interval between calving and the 1st insemination was inversely correlated with glucose and positively correlated with NEFA levels.

CONCLUSION

The changes of the studied analytes in mid-lactation cows resembled those that would happen during negative energy balance in early lactation cows and feed restriction in mid-lactation cows and may affect the general health and the performance of the cows.

An investigation on LD50 and subacute hepatic toxicity of Nigella sativa seed extracts in mice

Nigella sativa seeds (blackseed) have been used in traditional medicine for the treatment of a variety of diseases including diarrhea and asthma, and have been shown to have various useful pharmacological effects. In this study, acute and subacute toxicity of the aqueous, methanol and chloroform extracts of the seeds have been investigated. To determine their LD50, the aqueous, methanol and chloroform extracts were administered orally, in 4 different doses, 6, 9, 14 and 21 g/kg. Mortality rate and weight changes have also been measured in all groups for 3 and 7 days, respectively. No mortality has been observed in all groups and with all doses. Methanol extracts in all doses and chloroform extract in the dose of 21 g/kg significantly decreased animals weight. Hepatic toxicity of the extracts was also investigated in the dose of 6 g/kg/day orally for 14 consecutive days by measuring ALP, SGOT and SGPT activity in blood and hepatic histological study. Degenerative changes in hepatic cells have been observed only with aqueous extract of the seeds. In conclusion, Nigella sativa extracts are relatively nontoxic in the acute toxicity test, but the possibility of hepatic damage with its aqueous extract should be considered.