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S Mancini

Publications and source records attributed to S Mancini.

At least 37 records · Page 2Linked to original sources

Toward a tomographic picture of a Bose-Einstein condensate.

The possibilities of applying tomographic techniques to a Bose-Einstein condensate to reconstruct its ground state are investigated by means of numerical simulations. Two situations for which the density-matrix elements can be retrieved from atom counting probabilities are considered. The methods presented here allow one to distinguish among various possible quantum states.

Journal Article↗

[Locoregional anesthesia in inguinal hernia surgery].

BACKGROUND: It is a current opinion that local anesthesia (LA) is the primary choice in surgical treatment of the inguinal region, particularly herniorrhaphy. The LA technique personally used for herniorrhaphy is described: it consists of iliohypogastric, ilioinguinal and genito-femoral nerve blocks, and incision line anesthetic infiltration. METHODS: From January 1998 to April 1999, 95 patients underwent inguinal herniorrhaphy employing LA: 77 (81%) in elective surgery, 18 (19%) in emergency; 2 cases with bilateral hernia (97 total LA procedures). RESULTS: Partial success was obtained in only 8 cases (8.4%), which required an association with a hypnotic drug ("blended anesthesia": propofol or midazolam): there were no cases of conversion to general anesthesia. Specific complications of local anesthetic drugs infiltration developed in 8 cases on 97 LA procedures (8.2%), but none required reoperation: 6 inguinal hematomas, 1 female external genitalia hematoma, 1 hematocele. CONCLUSIONS: In conclusion, it is stressed that LA is the technique of choice in herniorrhaphy and surgery of other inguinal pathologies, associating high success rates, rare complications and rapid dismissal: this allows for easy management of the patients and a very important reduction of sanitary costs. The association of LA-hypnotic drugs (blended anesthesia) represents another important resource, since it avoids general anesthesia in many cases and allows a rapid psychophysical recovery.

Adult↗

[Severe acute pancreatitis. Clinical, diagnostic, and therapeutic features].

BACKGROUND: The aim of this study is to define the actual role of surgical therapy in severe acute necrotizing pancreatitis. METHODS: A retrospective analysis has been carried out on the surgical treatment of severe acute pancreatitis at the Institute of General Surgery and Surgical Specialties, University of Siena (Italy). From January 1980 to December 1997, 230 patients affected by acute pancreatitis were admitted to institution: 24 patients affected by severe disease (necrotizing pancreatitis: clinical and radiological diagnosis, by CT-scan) was choosen for this study. Of 24 patients, 15 were males and 9 females, with mean age of 55 years (range 30-80). In all cases, surgical procedure consisted in pancreatic necrosectomy, multiple abdominal and retroperitoneal drainage and closed management; operated patients with biliary pancreatitis underwent colecystectomy and, if necessary, common biliary duct drainage. RESULTS: The patients underwent surgical procedure, but the remaining 14 were treated by intensive medical care: mortality in these two groups was respectively 40% (4 cases) and 21% (3 cases). CONCLUSION: The conclusion is drawn that intensive medical care is the first therapeutic approach in severe acute pancreatitis, reserving surgery only to selected cases, as those affected by pancreatic infectes necrosis or those who get worse despite of conservative therapy. As to surgical technique, closed procedures vs open or semiopen, and conservative surgery (necrosectomy, multiple drainage and abdominal washing) vs anatomical resection are preferred.

Adult↗

TCR alpha-chain repertoire in pTalpha-deficient mice is diverse and developmentally regulated: implications for pre-TCR functions and TCRA gene rearrangement.

Pre-TCR expression on developing thymocytes allows cells with productive TCRB gene rearrangements to further differentiate. In wild-type mice, most TCRA gene rearrangements are initiated after pre-TCR expression. However, in pTalpha-deficient mice, a substantial number of alphabeta+ thymocytes are still produced, in part because early TCR alpha-chain expression can rescue immature thymocytes from cell death. In this study, the nature of these TCR alpha-chains, produced and expressed in the absence of pre-TCR expression, have been analyzed. We show, by FACS analysis and sequencing of rearranged transcripts, that the TCRA repertoire is diverse in pTalpha-/- mice and that the developmental regulation of AJ segment use is maintained, yet slightly delayed around birth when compared with wild-type mice. We also found that T cell differentiation is more affected by pTalpha inactivation during late gestation than later in life. These data suggest that the pre-TCR is not functionally required for the initiation and regulation of TCRA gene rearrangement and that fetal thymocytes are more dependent than adult cells on pTalpha-derived signals for their differentiation.

Animals↗

Ex vivo pharmacological purging of leukapheresis collections with nitrogen mustard: amifostine pretreatment improves both early and late peripheral blood progenitor cell recovery.

Ex vivo pharmacological purging of bone marrow has been used to eliminate clonogenic tumor cells contaminating the autograft and potentially responsible of relapse. A considerable improvement of pharmacological purging would be achieved only if normal marrow progenitor cells could be selectively protected by the cytotoxicity of these agents. Amifostine (WR-2721; Ethyol), a phosphorylated aminothiol compound, has been shown to have this property both in vivo and in vitro. We describe here, an experimental model for ex vivo purging of peripheral blood progenitor cell (PBPC) collections based on the combination of 3 mg/ml of amifostine and the alkylating agent nitrogen mustard. Amifostine pretreatment resulted in a statistically significant protection of normal late and early progenitor cells. Under the same experimental conditions, we observed a 4-6 log reduction of contaminating leukemic cells (i.e., K-562 and CEM) and in contrast to the protection of normal peripheral blood progenitor cells, preincubation of contaminating K-562 or CEM with amifostine did not significantly alter the LD95 nitrogen mustard concentration. Moreover, when we tested fresh human leukemia progenitor cells, amifostine pretreatment sensitized the leukemic cells to the cytotoxic effects of NM.

Amifostine↗

Activation of neutrophil collagenase in periodontitis.

Neutrophil collagenase (matrix metalloproteinase 8 [MMP-8]) is an important mediator of tissue destruction in inflammatory diseases. Studies of anaerobic periodontal infections have shown that active MMP-8 in gingival crevicular fluid is associated with the degradation of periodontal tissues in progressive periodontitis whereas the latent enzyme is predominant in gingivitis. Since the activation of MMP-8 appears to be a crucial step in periodontitis, we have examined the activation of MMP-8 in gingival crevicular fluid samples by using a soluble biotinylated collagen substrate. Analysis of gingival crevicular fluid in periodontitis, gingivitis, and controls revealed sixfold (P < 0.001)-higher levels of active collagenase in periodontitis (n = 12) samples compared to gingivitis (n = 17) samples, which exhibited low levels of activity, while controls (n = 25) showed no activity. After gingival crevicular fluid was collected, no further activation of latent collagenase occurred in vitro. Although both MMP-1 and MMP-8, but not MMP-13, could be detected by immunoblots, blocking antibodies to MMP-1 showed that collagenase activity was largely contributed by MMP-8, which was localized to the matrix of diseased tissues. The MMP-8 in gingival crevicular fluid migrated primarily as a 60-kDa form with smaller amounts of a 78-kDa species, whereas MMP-8 isolated from peripheral neutrophils migrated at 70 and 89 kDa, corresponding to active and latent forms of the enzyme, respectively. Most of the MMP-8 in the 60- and 70-kDa bands selectively bound to tissue inhibitor of metalloproteinase 2 and collagen, indicating that most, but not all, of the enzyme in these bands was in an activated form. However, the amounts of the 78- and 60-kDa forms from gingival crevicular fluid in different samples did not correlate (r2 = 0.028) with the latent and active enzyme measured by collagenase assay. Collectively, these studies have identified distinct forms of latent and active MMP-8 in gingival crevicular fluid that appear to result from a unique activation mechanism that occurs in periodontitis. The complexity of MMP-8 activation is further indicated by the presence of latent, activated, and superactivated forms of MMP-8 in the 60- and 70-kDa bands obtained from gingival crevicular fluid and neutrophil samples, respectively.

Case-Control Studies↗

Assessment of a novel screening test for neutrophil collagenase activity in the diagnosis of periodontal diseases.

BACKGROUND: Increased levels of active neutrophil collagenase (MMP-8) in the gingival crevicular fluid (GCF) are associated with progressive periodontitis. The measurement of this enzyme in GCF could facilitate diagnosis. However, assays with sufficient sensitivity to detect collagenase in whole-mouth GCF currently use radiolabeled substrates and require several days to complete. To provide more rapid analyses of collagenase activity that are better adapted to clinical studies, we developed and validated a novel assay (soluble biotinylated-collagen assay: SBA) based on chemiluminescent detection of biotinylated collagen digestion products. METHODS: The concordance of the novel SBA assay with a radioactive collagen substrate assay was assessed by parallel analyses of enzyme from 35 neutrophil preparations and from 41 samples of GCF from periodontitis patients, followed by Pearson correlation analysis. To test whether the assay appropriately measured MMP-8 activity, enzyme activity was assessed after incubation with specific collagenase blockers. We examined the diagnostic utility of the SBA in cross-sectional and longitudinal analyses of 125 patients with adult periodontitis, 5 patients with early-onset periodontitis, 1 edentulous patient, and in 32 control patients without periodontitis. RESULTS: The assay detected <56 pg collagen degraded/hour/microl sample, which is comparable to the most sensitive radioactive assay. The total assay time was 22 hours and reproducibility on replicate measurements was high (r = 0.96). In direct comparisons of MMP-8 activity in GCF with enzyme from peripheral blood neutrophils using the SBA and radioactive assays, there was a high correlation (r = 0.97). As expected, EDTA and TIMP-1 and -2, known inhibitors of MMP-8, completely blocked enzyme activity with this assay. Cross-sectional and longitudinal analyses of GCF showed that MMP-8 activity was >18-fold higher in severe periodontitis than in stable periodontitis and decreased to <25% of pretreatment levels following therapy. Based on measurements of collagenase activity in different disease groups, we estimated a value of 80 nano units as a threshold for severe periodontitis. CONCLUSIONS: These results indicate that active MMP-8 is detected in GCF by a novel assay that is specific, simple, rapid, and reproducible and which may facilitate diagnostic discrimination between stable and progressive lesions.

Adult↗

[Blunt traumatic rupture of the diaphragm].

Lesions of the diaphragm are uncommon but important complications of blunt thoraco-abdominal traumas. Their incidence is increasing over the last decades as a consequence of the increase of the road traumatology. Preoperative diagnosis is often difficult especially when the diaphragmatic lesion is associated with other skeletal or visceral injuries that may mask the clinical or radiological signs. The Authors report 12 cases of traumatic lesions of the diaphragm due to blunt trauma observed from 1980 to 1997 and that underwent surgery. In particular they discuss about the importance of an early diagnosis and a correct surgical approach to reduce morbidity and mortality. Nine patients were operated by laparotomy; thoracotomy was performed in one case and the combined approach in the last two patients.

Adult↗

Adult colonic intussusception caused by malignant tumor of the transverse colon.

Adult colonic intussusception is rare and often originates from neoplasms. In emergency situations it can be difficult to diagnose. Our aim was to show how the integration of readily available diagnostic means in emergency situations can help in making a correct diagnosis of this disease. A 68-year old male patient presented with vomiting and abdominal pain. The abdomen was distended, with pain to palpation in the left quadrants without a mass. Plain radiographs of the abdomen showed a large amount of gas in the small bowel and in the right and transverse colon. A barium enema demonstrated an endoluminal filling defect in the descending colon. Abdominal ultrasonography revealed the presence of intraperitoneal fluid and thickened left colonic wall at the site of the lesion, with an aspect of a "double ring" consistent with intussusception. A solid formation was also revealed at a point distal to the thickened colonic wall. At emergency laparotomy an approximately 8-cm-long mass was palpable through the left colon. A colostomy was fashioned, and subsequently colonoscopy revealed the presence of a left colon tumor. At the subsequent operation an invagination of the left transverse colon into the descending colon was confirmed. The left transverse and descending colon were resected with high ligation of the left colic artery. Macroscopic examination of the invaginating head showed a vegetating transverse colon neoplasm. We conclude that in emergency settings the association of readily available diagnostic means such as plain abdominal radiography, water soluble contrast enema and ultrasonography may yield reliable information for diagnosing colonic intussusception.

Adenocarcinoma, Mucinous↗

Management of gingival vitiligo with the use of a tattoo technique.

The purpose of this report is to describe the management of gingival vitiligo in a black female. This patient was referred by her psychiatrist to the Mount Sinai Hospital Dental Department (Toronto) for assessment of progressive loss in gingival pigmentation. According to her psychiatrist this loss of pigmentation, which the patient indicated may be considered in Africa as a hallmark of HIV infection, was a significant exogenous factor in relation to the patient's ongoing clinical depression. After obtaining informed consent, a modification of a tattooing method used for skin was applied to the patient's attached gingival tissues. Test sites were tattooed prior to performing full gingival tattooing under local anaesthesia. The results demonstrate that it was possible to restore this patient's gingival pigmentation in a highly esthetically acceptable manner. The resulting coloration was reminiscent of the patient's natural pigmentation that had been lost ostensibly because of her systemic disorder. Our findings also showed that the artificial pigmentation established via the tattoo method was stable 4 months postoperatively and continues to be stable, as expected. A profound improvement in the patient's mood was noted.

Adult↗

[Recurrent abdominal pain caused by nodular focal hyperplasia of the liver. A case report].

A case of focal nodular hyperplasia of the liver in childhood (FNH or NRC) is reported; a conservative approach is usually preferred in this disease when the diagnosis is surely identified, and a follow-up for some years is recommended. Despite the increased accuracy of modern imaging methods none of them, singly or together, is able to differentiate a malignant lesion with certainty and histological confirmation is mandatory. In the case described a laparotomy frozen section was performed but it was not possible to make a diagnosis and the liver mass was removed. The patient had a complete relief of symptoms with no evidence of recurrence in the follow-up. A review of the literature has been made, trying to point out this disease and its treatment.

Abdominal Pain↗

Factors affecting hemopoietic recovery after high-dose therapy and autologous peripheral blood progenitor cell transplantation: a single center experience.

BACKGROUND AND OBJECTIVE: While the minimum number of CD34+ cells required for complete and long-lasting engraftment is quite well established, there is not general agreement about the optimal number of CD34+ per kg needed in order to obtain engraftment as rapidly as possible. In the present study we assess factors affecting hemopoietic recovery and the optimal peripheral blood progenitor cell (PBPC) number for rapid engraftment in patients treated with high-dose therapy. DESIGN AND METHODS: We enrolled 80 consecutive patients affected by hematologic and non-hematologic malignancies treated with a median of 10 chemotherapy courses (range 3-38). PBPC collection was performed after mobilization with high-dose chemotherapy and G-CSF 5 micrograms/kg/day. The circulating and harvested CD34+ cells were recognized in the cytofluorimetric CD45+/CD14- lymphocyte gate. After myeloablative therapy, PBPC infusion was followed by G-CSF 5 micrograms/kg/day from day +5 until WBC > or = 5.0 x 10(9)/L. Univariate and multivariate Cox analyses were performed to investigate factors affecting hemopoietic recovery. The Kaplan-Meier probabilities of hemopoietic reconstitution were compared by log-rank test to assess the optimal CD34+ cell number for rapid engraftment. RESULTS: We performed a median of two apheresis (range 1-4) per patient and we infused a median of 6.1 x 10(6) CD34+ cells/kg (range 0.5-30.5). Absolute neutrophil count (ANC) > 0.5 x 10(9)/L was reached after 11 days (range 8-15). The only factor affecting granulocyte recovery proved to be the CD34+ cell number; 5.0 to 7.8 x 10(6) CD34+ cells/kg allowed a significantly faster granulocyte recovery than < 2.5 x 10(6) CD34+ cells/kg (p = 0.0312). Platelet transfusion independence (> 20 x 10(9)/L) and 50 x 10(9)/L platelets were reached after 12 (range 8-24) and 15 days (range 9-40), respectively. The CD34+ cell number was also the only factor affecting platelet recovery; the number of 5.0 to 7.8 CD34+ cells/kg allowed a significantly faster platelet recovery than the lower dose, whereas a higher number did not. No late graft failures were observed. Patients receiving 5.0 to 7.8 x 10(9) CD34+ cells/kg had a significantly shorter duration of neutropenia, fewer platelet transfusions and less time spent in hospital than those receiving lower number did, whereas patients transplanted with a higher number had no advantage. INTERPRETATION AND CONCLUSIONS: When G-CSF is employed both for PBPC mobilization and after PBPC transplantation, the CD34+ cell number is the only factor that affects hemopoietic recovery. Moreover, > 5.0 x 10(6) CD34+ cells/kg is the optimal number for obtaining rapid platelet recovery and reducing the costs of HDT but there is no advantage exceeding the threshold of 7.8 x 10(6) CD34+ cells/kg.

Adolescent↗

[Postoperative follow-up after extraction of an impacted lower third molar].

BACKGROUND: On the basis of an anatomo-surgical classification adopted in our Department, that divides impacted lower third molars into (1) ectopic, (2) dystopic and (3) in the proper anatomical site, and the latter into Class A (complete bone impaction without pathology of the second molar), Class B (mucosal impaction with pathology of the second molar: Subclass B1, if the mucosa distal to the second molar is of a normal amount; Subclass B2, if the retromolar mucosa is plentiful), and Class C (mucosal semi-impaction), the authors carried out a comparative study on 20 patients who underwent extraction of both Class C lower third molars. METHODS: These operations were performed, in each patient, on one side raising an Archer's flap and on the other introducing a modification of the incision lines using Z-plasty for flap design. The patients were examined from the first postoperative hours up to the 7th day following a protocol aimed at monitoring the postoperative variables pain, edema, trismus, infection and healing time. RESULTS AND CONCLUSIONS: The preliminary results, analyzed by Student's "t"-test, are statistically significant (p < 0.05), and favour the hypothesis that the technical modification proposed for the flap, by permitting a better closure of the socket, involves a lesser incidence of postoperative complications and in any case a more comfortable postoperative course.

Adult↗

Pharmacologic bone marrow purging: is there any place for etoposide? In vitro comparison with mafosfamide.

Residual leukemic cells in a bone marrow graft may increase the risk of relapse after autotransplantation. We have compared the efficacy of etoposide with that of mafosfamide, which has been used mainly for purging in acute leukemias. First, we examined the effects of VP-16 and ASTA-Z on the normal hematopoietic progenitors and on the erythroleukemic cell K562. Subsequently, we evaluated purging activity in cocultures using two different ratios of leukemic contamination. The most effective drug concentrations in inhibiting 100% of K562 growth were 50 micrograms/ml of ASTA-Z and 70 micrograms of VP-16. Residual growth of normal colony-forming units-granulocyte-macrophage (CFU-GM) was 4.8% with VP-16 and 32.5% with ASTA-Z. In treated cocultures, ASTA-Z produced a higher inhibition of the K562 line than VP-16 at both levels of leukemic cell contamination. At 0.5% contamination, VP-16 showed higher toxicity toward normal hematopoietic progenitors than ASTA-Z. At the 5% contamination level, VP-16 completely inhibited colony formation, whereas ASTA-Z spared some normal progenitor cells (21.2%). In conclusion, in our experimental model, VP-16 did not show improved efficacy over ASTA-Z in killing leukemic cells and in sparing normal progenitors.

Antineoplastic Agents↗