TASK DEFINITION: Given a passage with a context and an answer, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.
PROBLEM: Context: Interferon (IFN)-γ is a major cytokine produced by immune cells that plays diverse roles in modulating both the immune system and bone metabolism, but its role in autogenous bone grafting remains unknown. Here, we present that local IFN-γ administration improved the efficacy of autogenous bone graft treatment in an experimental rat model.', 'An autogenous bone graft model was prepared with critically sized rat calvariae defects. Four weeks (w) after bone graft implantation, rats were treated locally with IFN-γ or were not treated. The effect of IFN-γ on bone formation was evaluated for up to 8w with micro-computed tomography, quantitative histomorphometry, and Von Kossa staining. Osteoclastogenesis was assessed by tartrate-resistant acid phosphatase staining. Immunohistochemistry staining or quantitative polymerase chain reactions were used to estimate the expression of osteoclast differentiation factor and inflammatory cytokines including tumor necrosis factor (TNF)-α, a well-known stimulant of osteoclastogenesis and an inhibitor of osteoblast activity, in defects.', 'Newly formed bone gradually replaced the autogenous bone grafts within 4w, although severe bone resorption with osteoclastogenesis and TNF-α expression occurred after 6w in the absence of IFN-γ administration. IFN-γ administration markedly attenuated bone loss, osteoclastogenesis, and TNF-α expression, while it enhanced bone formation at 8w.
Answer: Local IFN-γ administration promoted bone formation in autogenous bone grafts possibly via regulating osteoclastogenesis and TNF-α expression. The data provide insights into the potential roles of IFN-γ in autogenous bone grafting.

SOLUTION: Does interferon-γ enhance the efficacy of autogenous bone grafts by inhibiting postoperative bone resorption in rat calvarial defects?

PROBLEM: Context: A prospective radiographic analysis of deformity correction during the balloon kyphoplasty procedure.', 'To determine the spontaneous reduction of the deformity in prone position, the subsequent deformity correction by the inflatable bone tamp, and the overall deformity correction after deposition of the cement.', 'Fracture mobility has been shown to contribute to fracture reduction in vertebroplasty. Spontaneous reduction has not been taken into account in recently published series of balloon kyphoplasty, but it must be considered when performing vertebral augmentation and when reporting and interpreting the significance of vertebral height restoration.', 'A consecutive series of 39 osteoporotic vertebral compression fractures were treated in 30 patients. Lateral radiographs were taken and analyzed at six different time points: 1) Preoperative standing. During the kyphoplasty procedure, four consecutive radiographs were obtained: 2) after placing the patient in prone position on the operation table, 3) after inflation of the bone tamp (IBT), 4) after deflation and removal of the IBT, and 5) after deposition of the cement. 6) Standing lateral radiographs were taken after the procedure. All fractures were analyzed for improvement in sagittal alignment (Cobb angle, kyphotic angle, sagittal index, vertebral height), complications, and reduction of pain (VAS).', 'Placement of the patient in prone position displayed a significant spontaneous reduction in deformity of 6.5 degrees +/- 4.1 degrees Cobb angle. Inflation of the IBT demonstrated a further reduction of the fracture and a significant improvement of the Cobb angle of 3.4 degrees compared with baseline prone. After deflation and removal of the IBT and placement of the cement, no significant loss of fracture reduction was seen. Postoperative measurement of the Cobb angle by means of standing radiographs demonstrated a 3.1 degrees significant loss of reduction compared with the intraoperative measurement in prone position after cement application. Cement leaks occurred in 9 of 39 vertebral fractures. All patients subjectively reported immediate relief of their typical fracture pain. The VAS score significantly improved from 8.7 +/- 1.4 before surgery to 2.3 +/- 0.9.
Answer: The restoration of height in kyphoplasty is attributed to dynamic fracture mobility as well as to the expansion of the inserted balloon tamp.

SOLUTION: Is balloon kyphoplasty effective in deformity correction of osteoporotic vertebral compression fractures?

PROBLEM: Context: Graft-versus-host-disease (GvHD) occurs in one-third or even half of bone marrow transplant (BMT) patients, involving three major target organs: gut, liver and skin.', 'The histopathological and immunohistochemical features of normal-looking skin in oncohaematological patients on day 100 after BMT were studied to find a possible relationship between the histopathological findings and clinical variables (history or clinical evidence of GvHD, previous therapeutic regimens or infections).', 'Fifty-one Caucasian oncohaematological patients, who had had an allogenic BMT, had a biopsy taken from normal-looking skin in nonsun-exposed areas (buttocks or the lumbar region), around the 100th day after BMT. The histology was studied, and the influence of clinical variables on the development of every different histopathological pattern was evaluated through statistical analysis.', 'Histopathological analysis based on morphological criteria revealed the presence of three different patterns: a postinflammatory pattern (45%), changes similar to grade I and II of GvHD (31%) and no significant changes (24%). Statistical analysis revealed that only the presence of peaks of cytomegalovirus (CMV) antigen in the blood within 100 days from BMT was significantly associated with the pattern of GvHD-like changes.
Answer: Normal-looking skin in 76% of BMT patients is not necessarily histologically normal. The pattern with more prominent changes, the GvHD-like pattern, has been found to be associated with a more frequent history of CMV antigen in the blood within 100 days from BMT.

SOLUTION:
Is normal-looking skin in oncohaematological patients after allogenic bone marrow transplantation normal?