ASBMR 30th Annual Meeting SU001–SU504
Bibliographic record
Abstract
Long-term aromatase inhibitors use causes bone loss and increase fracture risk secondary to induced estrogen deficiency.We postulated that alfacalcidol (vitamin D3 analog) could prevent the letrozole induced bone mineral loss.Fifty intact 1 month old female rats were randomly divided into five groups with 10 rat each; basal group (B) was sacrificed at start of the experiment; age matched control group (C); letrozole group (L) oral administration of 2 mg/kg per day; alfacalcidol group (A): oral administration of 0.1 ug/kg per day; group L+A: letrozole 2 mg/kg + Alfacalcidol 0.1 ug/kg per day for a period of 8 weeks.When animal sacrificed, serum estrone (E1), estradiol (E2), testosterone (T), LH, FSH, IGF-1 were measured and femoral bone mineral density were scanned by DEXA.Data was analyzed by One-Way ANOVA with group comparison.Eight weeks administration of Letrozole resulted in a significant increase in body weight, tibial and femoral bone length and a significant decrease in the ovary+utrus horn weight as compared to the non-treated groups with or without alfacalcidol.Letrozole administration increased serum T, LH, FSH, IGF-1 and suppressed E1 and E2 significantly.None of those parameters were affected by Alfacalcidol treatment.The result of DEXA shows that Letrozole increased femoral bone area (1.8±0.09cm 2 vs C; 1.64±0.07cm 2 (mean±S.D.), P<0.05) without a significant effect on the bone mineral content (0.39±0.02g vs C; 0.38±0.02g).Therefore, the BMD (217.8±4.4mg/cm 2 ) was significantly lower than that of the control group (229.8±4.9mg/cm 2 , P<0.05).Alfacalcidol increased the bone area (1.78±0.07cm 2 , P<0.05), bone mineral content (0.44±0.03g,P<0.05) and BMD (249.8±5.9mg/cm 2 , P<0.05) as compared to the C group.L+A combine intervention resulted in a significant increase in the bone area (1.91±0.09cm 2 , P<0.05 vs C, L and A groups), bone mineral content (0.46±0.03g,P<0.05 vs C and L groups) and BMD (236.8±8.0mg/cm 2 , P<0.05 vs C and L groups).This study demonstrates that Letrozole treatment to the young growing female rats enhances body weight and bone elongation due to elevation of both T and IGF-I with the suppression of E1 and E2.However, the bone density decreased significantly.We believe that Letrozole induced reduction in BMD was secondary to increase bone volume without corresponding increase in mineral deposition.Increased mineral deposition to the growing bone by Alfacalcidol demonstrates that it has theraputical value in preventing Letrozole induced bone osteopenia.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.001 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.002 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.002 | 0.001 |
| Insufficient payload (model declined to judge) | 0.143 | 0.110 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".