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D Dallari

Publications and source records attributed to D Dallari.

At least 19 recordsLinked to original sources
PubMed2006

Evaluation of bone healing enhancement by lyophilized bone grafts supplemented with platelet gel: a standardized methodology in patients with tibial osteotomy for genu varus.

Orthopedic practice may be adversely affected by an inadequate bone repair that might compromise the success of surgery. In recent years, new approaches have been sought to improve bone healing by accelerating the rate of new bone formation and the maturation of the matrix. There is currently great interest in procedures involving the use of platelet gel (PG) to improve tissue healing, with satisfactory results both in vitro and in maxillofacial surgery. Otherwise, to our knowledge, only a preliminary clinical study was undertaken in the orthopedic field [Kitoh et al., Bone 2004;35:892-898] and the efficacy of PG is still controversial. Our paper focuses on the effect on bone regeneration by adding PG to lyophilized bone chips used for orthopedic applications. The clinical model and the laboratory methodology were standardized. As a clinical model, we employed the first series of patients of a randomized case-control study undergoing high tibial osteotomy (HTO) for genu varus. Ten subjects were enrolled: in 5 patients lyophilized bone chips supplemented with PG were inserted during tibial osteotomy (group A); 5 patients were used as a control (group B) and lyophilized bone chips without gel were applied. Forty-five days after surgery, computed tomography scan guided biopsies of grafted areas were obtained and the bone maturation was evaluated by a standardized methodology: the osteogenic and angiogenic processes were semi-quantitatively characterized by using histomorphometry, and the mineral component of the lyophilized and host bone was analyzed by using X-ray diffraction technique with sample microfocusing and microradiography. Lyophilized bone with PG seems to accelerate the healing process, as shown by new vessel formation and deposition of newly formed bone, with no evidence of inflammatory cell infiltrate, when compared with lyophilized bone without gel. On the contrary, lyophilized bone undergo a resorption process, and a fibrous tissue often fills the spaces between chips. A histiocytic/giant-cell reaction is sometimes present. Otherwise, no differences have been found concerning microstructure. Our findings show the reliability of the methodology used to monitor early bone repair. The completion of the study and the evaluation of the ultimate clinical outcome are necessary in order to verify PG in vivo effects in orthopedic surgery.

Adult↗
PubMed2006

In vivo study on the healing of bone defects treated with bone marrow stromal cells, platelet-rich plasma, and freeze-dried bone allografts, alone and in combination.

The repair of confined trabecular bone defects in rabbits treated by autologous bone marrow stromal cells (BMSC), platelet-rich plasma (PRP), freeze-dried bone allografts (FDBA) alone and in combination (BMSC + PRP; FDBA + BMSC; FDBA + PRP; FDBA + PRP + BMSC) was compared. A critical size defect was created in the distal part of the femurs of 48 adult rabbits. Histology and histomorphometry were used in the evaluation of healing at 2, 4, and 12 weeks after surgery. The healing rate (%) was calculated by measuring the residual bone defect area. Architecture of the newly formed bone was compared with that of bone at the same distal femur area of healthy rabbits. The defect healing rate was higher in PRP + BMSC, FDBA + PRP, FDBA + BMSC, and FDBA + PRP + BMSC treatments, while lower values were achieved with PRP treatment at all experimental times. The highest bone-healing rate at 2 weeks was achieved with FDBA + PRP + BMSC treatment, which resulted significantly different from PRP (p < 0.05) and BMSC (p < 0.05) treatments. At 4 weeks, the bone-healing rate increased except for PRP treatment. Finally, the bone-healing rate of FDBA + PRP, FDBA + BMSC, and FDBA + PRP + BMSC was significantly higher than that of PRP at 12 weeks (p < 0.05). At 12 weeks, significant differences still existed between PRP, BMSC, and FDBA groups and normal bone (p < 0.05). These results showed that the combination of FDBA, BMSC and PRP permitted an acceleration in bone healing and bone remodeling processes.

Animals↗
PubMed2004

Deep peroneal nerve paresis in a runner caused by ganglion at capitulum peronei. Case report and review of the literature.

Although lateral popliteal sciatic nerve damage is not one of the commonest diseases in the general population, it is quite frequent among athletes. Several physiopathologic mechanisms have been thought to bring about this damage in athletes. Soft tissue ganglions with neurological involvement of the lateral popliteal sciatic nerve or its terminal rami are in differential diagnosis with several lesions of this area, as direct or indirect trauma, subcutaneous rupture of anterior tibialis muscle and long peroneal muscle, disc hernia, intraspinal tumor, anterior tarsal tunnel syndrome, cysts, neurofibroma, baker's cyst, vascular claudication, stenosing or inflammatory pathology of 2(nd) motoneuron, antimicrobial agents for urinary tract infection (nitrofurnantoin). The authors report the case of a 34-year-old amateur athlete with a recent paralysis of the hallux extensor, paresis of the toe extensor and hyposthenia of the tibialis anterior. The patient had been suffering from episodes of lumbalgia for a long time. He was sent to us because neurological damage due to disc herniation was suspected. Electromyography, sonography, and CT showed peripheral compression of the deep peroneal nerve caused by a mucous cyst at the capitulum peronei, a ''rare'' condition. The patient underwent surgery to excise the cyst, which led to the rapid resolution of the nerve deficit shown by clinical and electromyographical tests. A meticulous anamnesis and accurate objective examination, followed by specific tests (radiographs, sonography, and possibly CT scan) generally enable a correct diagnosis to be made. If diagnosis and therapy are carried out correctly, and without delay, symptoms quickly resolve and the nerve deficit progressively regresses.

Adult↗
PubMed2000

Sister chromatid exchange in patients with joint prostheses.

The evaluation of sister chromatid exchanges (SCE) is used to establish the cytogenic damage in subjects exposed to toxic substances. The test is considered to be 1 of the most sensitive and accurate indicators of damage and responds to toxic chemicals at low doses. We evaluated the incidence of SCE in peripheral lymphocytes of patients with articular prostheses. Subjects with prostheses made of titanium-aluminium-vanadium alloys presented a significantly higher SCE number than the control population (6.3+/-2.3 vs 4.4+/-1.3; P = .0128), whereas subjects with prostheses made of chrome-cobalt alloy or mixed prostheses presented a higher SCE value than the controls but not significantly different. The presence of high-frequency cells was alarming only in 5 patients, 4 of whom had titanium alloy prostheses, whereas none belonged to the control group. The number of SCE was not affected by the presence of bone-cement used in prosthesis fixation or by the implant duration. The indication of possible cytogenic damage in patients with titanium alloy prostheses that emerged from this study should be considered carefully, even though the sample population was small.

Adult↗
PubMed1998

Bone-resorbing cytokines in serum of patients with aseptic loosening of hip prostheses.

Our aim was to determine if the serum levels of bone-resorbing cytokines (IL-1beta, TNF-alpha, IL-6, GM-CSF) are altered in patients with aseptic loosening of a total hip prosthesis, and if such levels are influenced by the type of implant. We determined cytokine levels in sera from 35 patients before revision for failed total hip arthroplasty and compared them with those in 25 healthy donors. We also assessed the soluble receptor of interleukin-2 (sIL-2r) in serum as an indication of a specific immune reaction against the implant. Our findings showed that the sIL-2r and TNF-alpha serum level did not change. The IL-6 level was not significantly altered, but was higher in patients with TiAIV prostheses than in those with a CrCoMo implant and in patients with cemented prostheses. The IL-1beta level was found to be higher in those with a TiAIV cemented prosthesis than in the control group (p=0.0001) and other groups of patients (p=0.003 v uncemented TiAIV, p=0.01 v cemented CrCoMo, p=0.001 v uncemented CrCoMo). The GM-CSF level significantly increased in patients compared with healthy subjects (p=0.008), and it was higher in those with cemented than with uncemented implants (p=0.01). Only patients with cementless CrCoMo prostheses had levels of GM-CSF similar to those of the control group. The highest GM-CSF concentrations were observed in patients treated with non-steroidal anti-inflammatory drugs (NSAIDs) in the last months before revision (p=0.04). In addition, when massive osteolysis was observed, the level of GM-CSF tended to decrease to that of the control group.

Acetabulum↗
PubMed1996

Anion binding to mitochondrial cytochromes c studied through electrochemistry. Effects of the neutralization of surface charges on the redox potential.

The redox potential of horse and bovine heart cytochromes c determined through cyclic voltammetry is exploited to probe for anion-protein interactions, using a Debye-Hückel-based model. In parallel, protein charge neutralization resulting from specific anion binding allows monitoring for surface-charge/E(o) relationships. This approach shows that a number of anions, most of which are of biological relevance, namely CI-, HPO(2-)4, HCO3-, NO3, SO(2-)4, CIO4-, citrate3- and oxalate2-, bind specifically to the protein surface, often in a sequential manner as a result of the presence of multiple sites with different affinities. The binding stoichiometries of the various anions toward a given cytochrome are in general different. Chloride and phosphate appear to bind to a greater extent to both proteins as compared to the other anions. Differences in binding specificity toward the two cytochromes, although highly sequence-related, are observed for a few anions. The data are discussed comparatively in terms of electrostatic and geometric properties of the anions and by reference to the proposed location and amino acid composition of the anion binding sites, when available. Specific binding of this large set of anions bearing different charges allows the electrostatic effect on Eo due to neutralization of net positive protein surface charge(s) to be monitored. (J)H NMR indeed indicates the absence of significant salt-induced structural perturbations, hence the above change in Eo is predominantly electrostatic in origin. A systematic study of protein surface-charge/Eo relationships using this approach is unprecedented. Values of 15-25 mV (extrapolated at zero ionic strength) are obtained for the decrease in Eo due to neutralization of one positive surface charge, which are of the same order of magnitude as previous estimates obtained with either mutation or chemical modification of surface lysines. The effects of the anion-induced decrease of net positive charge on Eo persist also at a relatively high ionic strength and add to the general effects related to the charge shielding of the protein as a whole due to the surrounding ionic atmosphere: hence the ionic strength dependence of the rate of electron transfer between cytochromes c and redox partners could also involve salt-induced changes in the driving force.

Animals↗
PubMed1995

Cyclic voltammetry and 1H-NMR of Rhodopseudomonas palustris cytochrome c2. Probing surface charges through anion-binding studies.

The effects of increasing concentrations of Cl-, ClO4-, and HCO3- on the redox potential of Rhodopseudomonas palustris cytochrome c2 indicate that the two polyatomic anions bind specifically to the protein at one site, while chloride simply exerts an ionic atmosphere effect. The change in E degree upon specific anion binding allows us to probe for the influence of surface charges on the redox potential of cytochromes c. The decrease in redox potential at null ionic strength (delta E degree I = 0) due to anion neutralization of one positive surface charge was found to be 23 mV with perchlorate and 33 mV with bicarbonate. These values compare reasonably well with previous theoretical predictions and estimates of the effect of charge alteration on the E degree values in cytochromes c chemically modified or mutated at surface lysines. These delta E degree values, determined on the unmodified protein, are unprecedented for c-type cytochromes. The anion-induced chemical shift changes of the hyperfine-shifted heme 1H-NMR resonances of the oxidized protein yield lower limit values of 53 M-1 and 18 M-1 for the affinity constant for specific HCO3- and ClO4- binding, respectively.

Anions↗
PubMed1991

Neoadjuvant chemotherapy for nonmetastatic osteosarcoma of the extremities.

Between September 1986 and December 1988, 125 patients with osteosarcoma of the extremities entered the second neoadjuvant study at the authors' institution. Patients received preoperatively two cycles of methotrexate (MTX) intravenously, followed by cisplatinum (CDP) intraarterially, plus adriamycin (ADM) intravenously. After surgery, the patients classified as "good responders" (more than 90% tumor necrosis) received ADM, MTX, and CDP, while the "poor responders" (less than 90% tumor necrosis) had a longer chemotherapy that included ifosfamide and etoposide (VP-16) in addition to MTX, ADM, and CDP. Limb salvage was possible in 85% of patients, 8% had an amputation, and 7% had a rotationplasty. The surgical margins were adequate (radical or wide) in 88% of cases and inadequate (marginal or intralesional) in 12%. At an average follow-up period of 28 months (range, 13 to 41), 109 patients (87%) remained continuously disease free, 15 (12%) relapsed with pulmonary metastases, and one patient (0.8%) had a local recurrence. Compared with the first neoadjuvant study at the authors' institution that used only MTX and CDP preoperatively, the percentage of limb salvages, "good responders," and continuously disease-free survival at two years was significantly higher in the second Rizzoli neoadjuvant study (85%, 74%, and 87% versus 77%, 52%, and 59%). Systemic toxicity because of chemotherapy was superimposable. A retrospective analysis of the real dose intensity for each patient demonstrated a correlation between the intensity of chemotherapy and prognosis.

Adolescent↗
PubMed1991

Telangiectatic osteogenic sarcoma of the extremities. Results in 17 patients treated with neoadjuvant chemotherapy.

Seventeen patients with telangiectatic osteogenic sarcoma (TOS) of the extremities were treated with neoadjuvant chemotherapy, according to two different protocols. Preoperatively, the patients received high-dose methotrexate (HD-MTX) and cisplatinum (CPD) (HD-MTX/CPD) and doxorubicin. CPD was delivered intraarterially, the other drugs intravenously. Limb-salvage surgery was performed in 12 instances, and five patients were treated with amputation. Postoperative chemotherapy was tailored according to the grade of chemotherapy-induced necrosis. In 13 cases (86%), the resultant grade of necrosis was greater than 90% (good responders). The mean follow-up interval was 3.5 years with a range of 18 to 78 months. Fourteen patients (82%) remained continuously disease-free, while three patients developed lung metastases. Two of these died because of uncontrolled disease, whereas the third patient is alive and disease-free after metastasectomy. No local recurrences were observed. These results are better than those observed in 215 contemporary cases of conventional osteosarcoma treated with the same protocols. This study confirms that TOS is not a uniformly lethal tumor as suggested by prior reports. By employing neoadjuvant chemotherapy, a high percentage of patients with TOS can be cured, and in most of them, a limb-sparing surgery is possible and safe.

Amputation, Surgical↗
PubMed1990

Primary chemotherapy and delayed surgery for malignant fibrous histiocytoma of bone in the extremity.

Between March 1983 and September 1988, 22 patients with non-metastatic malignant fibrous histiocytoma MFH of bone of the extremities were treated with two regimens of neo-adjuvant chemotherapy successively activated. Preoperatively, the patients received moderate doses of methotrexate and cisplatinum-Regimen 1- or high dose methotrexate, cisplatinum and adriamycin-Regimen 2. Cisplatinum was delivered intraarteriously, the other drugs intravenously. Limb salvage surgery was performed in 20 patients, and 2 patients were amputated. The surgical margins were adequate (radical or wide) in 18 cases and inadequate (marginal) in 4. The histologic response to chemotherapy was good (90% or more tumor necrosis) in 8 patients. In both regimens postoperative chemotherapy was tailored according to the grade of necrosis determined by preoperative treatment on the primary tumor. At an average follow-up of 40 months (15-70), 15 patients (68%) remained continuously disease-free and 7 relapsed with metastases. No local recurrences were observed. Regimen 2 was slightly more effective than Regimen 1 in terms of good histologic response (5/10 vs 1/12) and continuous disease-free survival (8/10 vs 7/127). The results demonstrate that, as in osteosarcoma, in non-metastatic malignant fibrous histiocytoma of bone in the extremities a high percentage of patients can be cured with neoadjuvant chemotherapy and that in most of them limb sparing surgery is possible and safe.

Adolescent↗
PubMed1990

The importance of dose-intensity in neoadjuvant chemotherapy of osteosarcoma: a retrospective analysis of high-dose methotrexate, cisplatinum and adriamycin used preoperatively.

The relationship between dose-intensity and outcome was retrospectively analyzed in 125 patients with osteosarcoma of the extremities treated at our institution with neoadjuvant chemotherapy between 1986 and 1988. Before surgery, chemotherapy was performed with high-dose methotrexate (HDMTX) i.v. followed by cisplatinum (CDP) i.a. and adriamycin (ADM) i.v. Postoperative chemotherapy was tailored according to the necrosis induced by preoperative treatment. Patients who were "good responders" had 31-weeks of chemotherapy with the same drugs utilized preoperatively, while "poor responder" patients received a longer treatment (40 weeks) in which ifosfamide and etoposide (VP-16) were added to HDMTX, CDP and ADM. At a median follow-up of 2 years (1-3 years) 100 patients (80%) remained continuously disease-free and 25 patients relapsed: 24 with lung metastases and 1 with local recurrence. According to the real dose-intensity received, calculated as a percentage of the dose intensity projected by the protocol, the continuously disease-free survival was 87% in the 82 patients who received 80% or more of the scheduled dose-intensity and only 65% for the 43 patients who received less than 80% of the projected dose-intensity. This difference is highly significant (P less than 0.01). These results suggest that in neoadjuvant chemotherapy of osteosarcoma the real dose-intensity delivered is a determinant of treatment outcome and therefore every effort should be made to avoid reductions of doses and delays of cycles of chemotherapy in these patients.

Adolescent↗
PubMed1989

Neoadjuvant chemotherapy for localized Ewing's sarcoma of the extremities: preliminary results of a protocol which uses surgery (alone or followed by radiotherapy) for local control.

From June 1983 to December 1985, thirty-eight patients with localized Ewing's sarcoma of the extremities were treated with a protocol that consisted of an initial nine week period of polychemotherapy (vincristine, adriamycin and cyclophosphamide) followed by local therapy and additional chemotherapy (vincristine, adriamycin, cyclophosphamide and dactinomycin) for one year. As local treatment all patients were offered surgery; thirty-two accepted and six refused. These six patients were locally treated with radiotherapy alone (50 Gy). In the remaining patients an amputation was performed in one case and a resection in thirty-one. In resected patients when a wide margin was achieved (24 cases) no further local treatment was performed; when it was marginal (5 cases) or intralesional (2 cases) radiotherapy at lower doses (40 Gy) followed. At mean follow-up of thirty-seven months the percentage of continuously disease-free patients was 50% for those treated with radiotherapy, 76% with surgery, and 85% with surgery and radiotherapy. Eight patients developed metastatic disease and two patients had local recurrence and metastases. The local recurrences were seen in one patient locally treated with surgery and in one locally treated with radiotherapy. Nine major local complications were observed: three in patients treated with radiotherapy, five in patients treated with surgery, and one in a patient treated with surgery and radiotherapy. These results indicate that after induction chemotherapy conservative surgery is possible in almost all cases of Ewing's sarcoma of the extremities and that such treatment is better than radiotherapy alone as local therapy.

Adolescent↗
PubMed1989

Primary chemotherapy and delayed surgery (neoadjuvant chemotherapy) for telangiectatic osteogenic sarcoma of the extremities.

Twelve patients with telangiectatic osteogenic sarcoma (TOS) of the extremities were treated with neoadjuvant chemotherapy, according to two different protocols. Preoperatively the patients received high-dose methotrexate(HD-MTX)/cisplatinum(CPD) or HD-MTX/CPD/adriamycin(ADM). CPD was delivered intra-arterially, the other drugs intravenously. Limb salvage surgery was performed in eight instances and four patients underwent amputation. Post operative chemotherapy was tailored according to the grade of necrosis determined by preoperative treatment on the primary tumor. In ten cases (83%) the grade of necrosis resulted higher than 95%. The mean length of follow-up was 3.5 years with a range of 18 to 72 months. Ten patients (83%) remained continuously disease-free, while two patients developed lung metastases and died of uncontrolled disease. No local recurrences were observed. These results are better than those observed in 167 contemporary cases of conventional osteosarcoma treated with the same protocols. This study confirms that TOS is not always a lethal tumor as suggested by prior reports. Employing neoadjuvant chemotherapy a high percentage of patients with TOS can be cured and in most of them, limb sparing surgery is possible and safe.

Adolescent↗
PubMed1988

Metastatic patterns in osteosarcoma.

The clinical courses of 193 patients with high-grade, non-metastatic osteosarcoma were reviewed to ascertain the evolution of the natural history of the disease. All patients had the primary lesion in the extremities and were treated at the Rizzoli Orthopaedic Institute between 1976 and 1982 with surgery alone (30 cases) or surgery plus adjuvant chemotherapy (163 cases). All patients were regularly followed at our Institute. One hundred and fourteen patients, of which 27 were treated with surgery alone and 87 treated with adjuvant chemotherapy, developed overt metastatic disease. No differences were found concerning the sites of the first relapse which, for approximately 90% of cases, were lungs in both groups. However, in the group of patients treated with adjuvant chemotherapy the development of overt metastatic disease, as compared to non-adjuvant patients, was delayed with time (13 vs 8 months) and the number of metastatic nodules in the lung at first relapse was reduced. This alteration in metastatic pattern due to adjuvant chemotherapy is important because it allows surgical resection of pulmonary metastases in a larger number of patients (51% vs 29%).

Adult↗
PubMed1988

The effectiveness of chemotherapy in localized malignant fibrous histiocytoma (MFH) of bone: the Rizzoli Institute experience with 66 patients treated with surgery alone or surgery + adjuvant or neoadjuvant chemotherapy.

Between January, 1974 and July, 1985 66 patients with non-metastatic malignant fibrous histiocytoma (MFH) of bone in the estremities were surgically treated with amputation (34 cases) or resection (32 cases) according to the extension of the tumor. With the exception of 3 patients, who had severe medical contraindications to the chemotherapeutic drugs, all the patients were offered, in addition to the surgery, adjuvant chemotherapy (patients treated before 1983) or neoadjuvant chemotherapy (patients treated after 1983). 33 patients accepted, while 30 wanted to be treated with surgery alone. At median follow-up of 7 years (3-14) 25 patients remained continuously disease-free and 41 relapsed (27 with metastatic disease, 1 with local recurrence and 13 with both metastases and local recurrence). The percentage of patients who remained continuously disease-free was 12.1% (4:33) in the group of patients treated with surgery alone and 63.5% (21:33) in the group treated with surgery plus adjuvant or neoadjuvant chemotherapy. Although the two groups of patients were not completely superimposable (the patients treated with surgery alone were older and more often the MFH arose in pre-existing bone lesions) these results seem to suggest the usefulness of adjuvant and neoadjuvant chemotherapy for this tumor.

Adolescent↗