Biomedical subjects

P L Santi

Publications and source records attributed to P L Santi.

At least 19 recordsLinked to original sources

PubMed2006

Characterization and induction of human pre-adipocytes.

Human processed lipoaspirate is a source of multipotent adult stem cells that are able to differentiate between mesenchymal and neurogenic lineage. We characterized PLA cells by cytometry and then they were cultured to induce differentiation into myogenic and neurogenic lineage. Lipoaspirates were digested with collagenase to obtain the pellet, which was labelled with anti-CD44, anti-CD45, and anti-CD90. We used BD FACS Calibur flow cytometer to acquire cellular events. Some cells were cultured at 37 degrees C and 5% CO(2) in neurogenic or myogenic medium and analysed by immunocytochemistry, using Neuron specific enolase, Vimentin, Glial fibrillary acidic protein, Tau, MAP2 to confirm neurogenic differentiation, MyoD1, Myosin heavy chain, Actin smooth muscle, vimentin to confirm myogenic differentiation. The cytometry results suggest that a part of the cells are of a mesenchymal origin, among which there are progenitor endothelial cells and leucocytes. Microscopy observation already reveals neuronal morphology and longitudinal multinucleated cells compared to control cells. Neurogenic cells only express NSE (early neuronal progenitor marker), but not GFAP, Tau, MAP2 (mature neuron and glial markers); myogenic cells are positive for MyoD1 and Myosin heavy chain. This demonstrates that lipoaspirate cells are capable of differentiating in vitro over a short period of time, and could be employed in biological and clinical research, like mesenchymal adult stem cells.

Adipocytes↗

PubMed2006

Characterization of multipotent cells from human adult hair follicles.

Recent works demonstrated the presence of a multipotent epithelial cell population in the bulge region of adult human hair follicles. These cells can be cultured in vitro, thus leading to the preparation of dermal-epidermal substitutes which are applicable in the treatment of burns and ulcers. We evaluated the main marker expression in cells obtained from stripped human hair follicles. A pool of hair follicles were incubated at 37 degrees C and 5% CO(2) in a growth medium. The cells were then labelled with antibodies (anti-CD34, anti-CD38, anti-CD45, anti-CD90, anti-CD133, anti-CD146) and analysed by cytometry. We also used hair follicles for immunohistochemical studies, employing antibodies such as CD34, Actin Smooth Muscle, Filaggrin, Desmin, Vimentin, Glial Fibrillary Acidic Protein, Ki-67, PanCytokeratin, CK15, CK19. The cytometry results revealed that a part of bulge cells were CD34+ (1-2%). CD34+ population comprises both large, CD45-, CD133-, CD146- cells and small, CD45+, CD133+, CD146+ cells. Thus, a part of CD34+ cells present a mature endothelial marker (CD146). An expression of the proliferation marker Ki-67 and the stem cell marker CD34 is present in the follicle bulge region. In conclusion, we observed that the stripped hair follicle has the same multipotent cell population as adult and fetal scalp hair follicles.

Adult↗

PubMed2002

[Experimental model for the evaluation of topical application of a solution to help myocutaneous flap transposition].

The aim of this article is the evaluation of the topical application of a solution of hydrogen peroxide (H2O2) 8% and dimethyl sulphoxide (DMSO) 50% in order to reduce ischaemic failure in random skin flaps. This study was performed using a rabbit model. Two parallel, cephalad-based para-midline random cutaneous flap (10 cm x 2.5 cm) were elevated and resutured in place on the dorsum of 40 New Zealand rabbits. The 80 flaps thus obtained were then randomly divided into one control group and three experimental groups of 20 flaps each. Flaps from the control group (group A) were topically treated with saline, while flaps from experimental group B were treated with H2O2 8%, flaps from experimental group C with DMSO 50%, and flaps from experimental group D with a solution of 50% DMSO + 8% H2O2. Each solution was topically applied, 20 cc per three times a day, on the flaps for seven days, starting on the immediate postoperative period. Transcutaneous oxygen tension (Ptc O2) measurements were carried out in all flaps, 72 h after flap elevation. The percentage of surviving skin area of each flap was determined by planimetry 7 days after flap elevation. The mean surviving area of the group A (control) flaps was 71%. The mean surviving area of the group B (H2O2-treated) flaps was 72%. The mean surviving area of the group C (DMSO-treated) flaps was 76%, and that of the group D (DMSO + H2O2-treated) flaps was 92%. While no statistically significant differences were found between the survival rates of both the flaps treated with H2O2 or DMSO alone and that of the control group, the mean surviving rate of the DMSO + H2O2 treated flaps (+20%) was statistically higher than that of the control flaps. Similarly, a statistically significant difference has been found between the mean Ptc O2 values of the DMSO + H2O2 flaps and those of the other three groups of flaps.

Administration, Topical↗

PubMed2002

[Evaluation of the tolerability of Hydrogel breast implants: a pilot study].

BACKGROUND: During the 90s the widely publicised controversy regarding the use of silicone gel breast implants stimulated research into alternative alloplastic filling materials. In this context, a new type of breast implant, containing Carboxymethylcellulose at 3.7% in the form of Hydrogel, was introduced into the European market. METHODS: A preliminary pilot study was carried out to evaluate the tolerability and reliability of breast implants pre-filled with Hydrogel. A group of 12 consecutive patients was recruited for this purpose and underwent plastic surgery for breast augmentation or reconstruction (20 implants) at the Department of Plastic and Reconstructive Surgery at the University of Genoa between December 1996 and October 1997. All patients were then followed up for a minimum of 3.5 years. The mean age of patients was 50 years and ranged from 28 to 67 years old. After surgery the patients were examined at 4 weeks (evaluation of any immediate complications), 3 months, 6 months and 1 year (evaluation of any delayed complications). RESULTS: No immediate complications were reported in any patient. After 3.5 years of follow-up, the degree of capsular contraction according to Baker in these patients varies between 1 and 2. In general, the implants were very soft to touch even some time after surgery, above all in patients undergoing breast augmentation. Four implants (20%) were removed from 3 patients for reasons unconnected to the implants themselves (because of neoplasm in one case and due to inadequate volume in the other two patients). No case of rupture has been reported. CONCLUSIONS: This pilot study appears to confirm the validity of implants prefilled with Hydrogel in reconstructive or cosmetic breast surgery. A larger population and longer periods of minimum follow-up are obviously required to confirm these results over the long term.

Adult↗

PubMed2002

[Computer-based preoperative planning for breast reconstruction in the woman with unilateral breast hypoplasia].

BACKGROUND: Aim of this paper is to describe a computer program which can provide objective and quantitative data useful for the selection of the proper implant in order to obtain the symmetry with the contralateral breast in case of unilateral breast reconstruction by tissue expansion, especially for the surgeon without experience or for the occasional operator. METHODS: Our C++ program provides the final implant volume using the measurements of the semi-circumference and projection of the contralateral breast performed on the supine patient. The aim is the symmetry of the two breasts. RESULTS: According to our experience in breast reconstruction by tissue expanders, this program allows non invasive and simple measurements of the breast volume, useful to obtain the mammary symmetry. CONCLUSIONS: In case of breast reconstruction by tissue expansion, the preoperative evaluation is usually based on the surgeon's experience and on empirical observations without knowing the correct volume to reach. For this reason our program is useful to know the necessary volume for breast reconstruction, and therefore it allows the surgeon to obtain a better plastic result.

Adult↗

PubMed2001

[Minimally-invasive endoscopic transthoracic sympathectomy of the upper limbs. A new method].

OBJECTIVE: Indications for endoscopic transthoracic upper dorsal sympathectomy are axillary and palmar hyperhidrosis, upper extremities ischemia (due to, e.g., Raynaud s disease), and upper extremities causalgia. METHODS: At present, this methodology relies on (at least) double trocar insertion (per side) and/or carbon dioxide insufflation. Thus, although this approach, compared with the traditional open sympathectomy techniques, it guarantees the smallest number of postoperative complications, it still determines a certain amount of postoperative discomfort as well as a risk of complications related to carbon dioxide insufflation, as intraoperative profound bradycardia and hypotension due to mediastinal shift, and postoperative subcutaneous emphysema. From December 1995, we are using a minimally-invasive endoscopic transthoracic sympathectomy technique, performed by a single-entry specifically modified thoracoscope and without the need for carbon dioxide insufflation, with the aim to reduce the drawbacks associated with the above-mentioned currently adopted endoscopic techniques. After general anesthesia with double-lumen endotracheal tube, with the patient placed in a half-sitting position with both arms abduced to 90 degrees, a 1 cm incision is performed, along the midclavear line (in male patients) or the anterior axillary line (in female patients), in the second or third intercostal space. RESULTS: The effects of sympathectomy are immediate, and the patients wake up with warm and dry hands and axillae. CONCLUSIONS: In personal opinion, this single-entry technique, compared with other reported approaches, should minimize any damage to the intercostal neurovascular bundle, while avoiding the complications connected with carbon dioxide insufflation.

Arm↗

PubMed2001

[Computer planning for postmastectomy breast reconstruction by tissue expansion].

Aim of this paper is to present a computer program able to provide objective and quantitative data useful to guarantee the selection of the proper implant in order to obtain symmetry with the contralateral breast, in case of unilateral breast reconstruction by tissue expansion, especially for surgeons without experience or for occasional operators. Our C++ program provides the final implant volume using the measurements of the semi-circumference and projection of the contralateral breast performed on the supine patient. The aim is the symmetry of the two breasts. According to personal experience in breast reconstruction by tissue expanders, this program allows non invasive and simple measurements of the breast volume, useful to obtain the mammary symmetry. In case of breast reconstruction by tissue expansion, the preoperative evaluation is usually based on the surgeon experience and on the empirical observation without knowing the correct volume to reach. Since this program is useful to know the precise necessary volume for breast reconstruction, it allows the surgeon to obtain a better plastic result.

Breast Implants↗

PubMed2001

[Computer-aided preoperative planning of tissue expansion].

OBJECT: The aim of this paper is to introduce a computer program developed to provide objective and quantitative data useful to provide proper expander selection when a rectangular tissue expander has to be used. METHODS: The program has been developed to calculate the volume of a rectangular tissue expander to obtain the exact amount of yield necessary to allow for reconstruction of a determined defect. The only data to be supplied are the length and the width of the defect to be reconstructed. RESULTS: The accuracy of the results obtained by the computer program was tested clinically comparing preoperative data with volume measurements obtained at the end of the expansion procedure. In our study the resulting data did not show any statistically significant difference (p<0,05) between the two groups. CONCLUSIONS: In our opinion, although its use is not aimed at replacing clinical judgment based on experience and careful observation, this program may be considered a simple and useful adjunct for the inexperienced surgeon (or the occasional operator) planning to use a rectangular tissue expander.

Humans↗

PubMed2000

A single genetic origin for the G101W CDKN2A mutation in 20 melanoma-prone families.

Germline mutations within the coding region of CDKN2A have been observed in affected members of melanoma-prone families. G101W is the most common CDKN2A missense mutation identified to date. It has been reported in several families from around the world, with a particularly high occurrence in France and Italy. Given the frequency of this mutation, we were interested in determining whether the mutation resulted from a single origin or represented a mutational hotspot in the CDKN2A gene. In addition, given the geographical distribution of the mutation, we examined the date of origination of the mutation and its migratory spread. We examined 10 families from Italy, 4 families from the United States, and 6 families from France with the G101W mutation. The following eight markers were employed for the haplotype analysis: IFNA, D9S736, D9S1749, D9S942, D9S1748, D9S1604, D9S171, and D9S126. Our findings showed no significant evidence for mutational heterogeneity, suggesting that all studied families derived from a single ancestral haplotype on which the mutation arose. Using maximum-likelihood methods, we estimated the mutation to have arisen 97 generations ago (1-LOD-unit support interval 70-133 generations) providing some explanation for the wide geographical spread of this common mutation, particularly in southwestern Europe. The presence of a founder mutation in a defined geographic area can facilitate carrier detection and genetic counseling and can provide an opportunity to study disease penetrance and the effect of environmental factors on the background of a common genetic susceptibility.

Amino Acid Substitution↗

PubMed2000

Quantitative benefits provided by acute tissue expansion: a biomechanical study in human cadavers.

The aim of this study was to test the ex vivo biomechanical properties of acutely expanded cutaneous flaps to quantitatively assess the efficacy of intraoperative tissue expansion. A total of 14 fresh male cadavers were used for the study. In each cadaver, a rectangular (15 x 8 cm), proximally based flap was designed on each side of the body, in three different locations: lateral arm, anterior thorax, anterior thigh. In each cadaver, one randomly selected flap per each body region underwent acute-intermittent expansion, whereas the contralateral flap served as control. The biomechanical properties (stress/strain ratio, mean stiffness) of both expanded and control flaps were then assessed by means of a dynamometer and a force-transducer. The obtained data showed that the biomechanical benefits provided by acute tissue expansion were statistically different (P< 0.05) from those obtained by simple subcutaneous undermining. While no changes of length have been observed in the acutely expanded skin flaps as compared to control cutaneous flaps, a statistically significant gain in the compliance of the former has been recorded as compared to the biomechanical behaviour of the latter.

Adult↗

PubMed2000

[Intraoperative expansion of scalp flaps. Quantitative assessment].

BACKGROUND: The aim of this study was to test the ex-vivo biomechanical properties of acutely expanded scalp flaps, in order to quantitatively assess the efficacy of acute scalp expansion. METHODS: A total of 14 fresh male cadavers were used for the study. In each cadaver, a rectangular (4 x 10 cm), laterally-based flap was designed on each side of the scalp, starting from the superior margin of the external auditory canal. One randomly-selected flap per each scalp underwent acute-intermittent expansion (3-minute expansion-3-minute rest cycle per three times with the maximal expansion achievable), while the contralateral flap served as control. After the expansion process, the acutely-expanded flaps were measured to assess if the applied biomechanical stress have determined any changes in their dimensions. The biomechanical properties (stress/strain ratio, mean stiffness) of both expanded and control flaps were then assessed by means of a dynamometer and a force-transducer. RESULTS: The obtained data showed that the biomechanical benefits provided by acute scalp expansion were not statistically different (p < 0.05) from those obtained by simple subgaleal undermining. Neither any change of length nor any gain in the compliance have been observed in the acutely-expanded flaps as compared to control scalp flaps. CONCLUSIONS: In our opinion, a possible explanation (to be further validated) for the lack of effect of acute scalp expansion might be that inelastic galea aponeurotica did not allow the mechanical creep to exploit the inherent elastic properties of the overlying scalp skin.

Adult↗

PubMed1999

Characterization of ligurian melanoma families and risk of occurrence of other neoplasia.

Germline mutations impairing the p16(INK4)-function have previously been demonstrated to be responsible for genetic predisposition in at least one half of melanoma-prone kindreds of North European origin. Familial melanoma kindreds have also been found to present an increased risk of pancreatic cancer and other cancers, but results relative to more common neoplasias incidence, in particular, are heterogeneous. We report here a clinical-epidemiological study, including the presence of additional neoplasias, in 14 apparently unrelated kindreds coming from a small geographic region of Northern Italy (Liguria), having therefore lived for generations in similar environmental conditions. We identified the common p16 missense mutation (Gly101Trp) reported in several previously studied kindreds, in 7 of 14 families, whereas the remaining 7 families had no detectable mutations in the coding region of p16 gene. Median age at diagnosis and other melanoma features were studied. When compared with the expected figures, based on regional incidence rates, a significant excess of pancreatic cancer, with 4 cases diagnosed, and of breast cancer, with 7 cases, was observed. The 7 families without apparent CDKN2A involvement were also negative for hot-spot exon 2 mutation of CDK4. Environmental factors do not appear to play a role in the excess of non-melanoma neoplasia in our families, as somewhat substantiated by the control group, composed of spouses and members of non-affected branches; they do not reveal any increased cancer incidence compared with the general population. Furthermore, given the proven significance of interaction between the melanoma susceptibility gene and the propensity to sunburns and other environmental risk factors, our results, obtained from a small but homogeneous sample, may have important implications for further risk assessment studies.

Adolescent↗

PubMed1999

Serial scalp reductions: a biomechanical approach.

BACKGROUND: Several technical aspects of scalp-reduction procedures still need to be clearly elucidated: in particular, (a) the quantitative effects provided by different amounts of subgaleal undermining, (b) the immediate gains provided by increasing amount of tension when advancing a scalp flap, and (c) the eventual benefits provided by galeotomies. OBJECTIVE: The aim of the present paper is to report on some biomechanical properties of scalp flaps as related to serial scalp reduction procedures for correction of male pattern baldness. METHODS: Data were collected by stepwise loading of 20 scalp flaps, obtained by a reversed-Y scalp incision, after increasing amounts of undermining, as well as after performing three galeotomies. RESULTS: Increasing amounts of tension (while advancing a scalp flap) affect the compliance of a scalp flap in a non-linear fashion; increasing amounts of undermining permit obtaining significant, but not proportional, gains; performing galeotomies is a useful adjunct to decrease the amount of closing tension when performing scalp-reduction procedures. CONCLUSION: When performing serial scalp reductions, to take into account the biomechanics of scalp flaps may be of some utility in obtaining an optimal result.

Adult↗

PubMed1999

Topical application of DMSO as an adjunct to tissue expansion for breast reconstruction.

The aim of this study was to evaluate the effectiveness of topical 60% dimethyl sulphoxide (DMSO) prior to tissue expansion for breast reconstruction in reducing expander pressure and length of treatment. Forty patients undergoing immediate breast reconstruction with tissue expanders following modified radical mastectomy were consecutively divided into two groups of 20 subjects each: group A (control) and group B (experimental). Patients from group A underwent traditional tissue expansion, while, to patients of group B, before each filling session, topical 60% DMSO was applied to the skin overlying the expander by soaking-wet surgical sponges left in place for 30 min. The average inflated volume was 395 cc (range 250-580 cc) in group A, and 410 cc (range 240-620 cc) in group B; no statistically significant difference was found between these values. A statistically significant difference was found between the expansion time of group A (mean 6 sessions; range 4-10 sessions with one filling session per week) and group B (mean 4 sessions; range 2-6 sessions with one filling session per week). A statistically significant difference was also found between the average inflated volume per session of group A (90 cc; range 60-130 cc) and group B (120 cc; range 90-160 cc). According to the data obtained by tonometry, a statistically significant difference was found between the average pre-filling and post-filling pressures of group A (28.4 and 66.5 mmHg, respectively) and group B (22.1 and 64.3 mmHg, respectively). Clinical benefits of pre-filling topical applications of 60% DMSO observed in our trial were an enhancement of the total volume inflatable per session and a significant shortening of the total expansion period.

Administration, Cutaneous↗

PubMed1999

Intercellular adhesion molecule-1 (ICAM-1) and granulocyte-macrophage colony stimulating factor (GM-CSF) co-expression in cutaneous malignant melanoma lesions.

The expression of intercellular adhesion molecule-1 (ICAM-1) and granulocyte-macrophage colony stimulating factor (GM-CSF) was investigated in 25 melanoma patients by evaluating 34 fresh biopsy specimens. ICAM-1 in situ hybridization and immunochemistry for ICAM-1 and GM-CSF were performed. Most of the metastatic melanoma samples (12 out of 18) and a few of the primary melanoma lesions (three out of 16) showed ICAM-1 expression. The expression of ICAM-1 was significantly (P < 0.01) higher in metastatic lesions than in primary tumours. GM-CSF mRNA and protein were detected in 10 of the 18 metastatic samples and in two of the 15 primary lesions. A significantly high degree (P < 0.0002) of concordance between ICAM-1 and GM-CSF expression was observed: the samples that were negative or positive for ICAM-1 expression were correspondingly negative or positive for GM-CSF. Correlation with clinical and histological parameters was examined. The expression of both molecules in metastatic samples was found to be significantly (P < 0.001) associated with a shorter recurrence-free period. These findings, if confirmed by a wider number of patients, could suggest the prognostic value of the simultaneous, and probably co-ordinated, expression of ICAM-1 and GM-CSF. They also highlight the importance of preventive molecular and biochemical characterization of neoplastic cell cytokine receptors, specifically focusing on the particular cytokine to be used as anticancer therapy and/or as adjunct to chemotherapy.

Adult↗

PubMed1999

Cleft lip: a histochemical and ultrastructural analysis of lip muscles.

AIMS: In order to evaluate the pathogenesis of cleft-lip in relation to both the anatomical and structural anomalies of the mesenchymal tissues, the authors concluded that the presence of structural anomalies in the examined tissues could not explain the malformation, but might be a consequence of it. Delayed muscular development, asymmetrical distribution of the muscular fibres and their anomalous insertion suggest that the anatomical/functional loss clinically detectable in the orbicular muscle could be the result of a perinatal dysmorphological process rather than of a simple mesenchymal hypoplasia. METHODS: Schendel et al. suggested that a metabolic defect in the mitochondrial function could cause a deficiency in cell migration and proliferation responsible for the malformation in question. To establish whether the pathogenesis of the cleft-lip is associated with an alteration in mitochondrial functionality, eight patients affected by unilateral cleft-lip were subjected to a biopsy of the orbicular muscle during the course of reparative surgery. RESULTS: The results obtained showed: 1) a great variation in the size of muscle fibres; 2) the absence of ragged red fibres; 3) a normal oxidative function in the muscle fibres examined; 4) the absence of typologically significant groupings positive for myofibral ATPases. Furthermore, the morphology of the mitochondria was preserved in all cases and neither inclusions nor morphological or volumetric changes were detected. CONCLUSIONS: This preliminary data did not confirm the constant presence of mitochondrial pathology responsible for the malformation in question. In our opinion, the growth deficiency of the maxillary segment could be ascribed to the cicatrization of the surgical repair of the cleft-lip.

Adenosine Triphosphatases↗

PubMed1998

Pharmacological enhancement of cutaneous flap survival with topical dimethyl sulphoxide and hydrogen peroxide.

The present study was designed to investigate, in a rabbit model, the value of topical application of a solution of hydrogen peroxide (H2O2) 8% + dimethyl sulphoxide (DMSO) 50% in order to reduce ischaemic failure in random skin flaps. Two parallel, cephalad-based para-midline random cutaneous flap (10 cm x 2.5 cm) were elevated and resutured in place on the dorsum of 40 New Zealand rabbits. The 80 flaps thus obtained were then randomly divided into one control group and three experimental groups of 20 flaps each. Flaps from the control group (Group A) were topically treated with saline, while flaps from experimental Group B were treated with H2O2 8%, flaps from experimental Group C with DMSO 50%, and flaps from experimental Group D with a solution of 50% DMSO + 8% H2O2. Each solution was topically applied to the flaps, 20 ml three times a day for 7 days, starting in the immediate postoperative period. Transcutaneous oxygen tension (PtcO2) measurements were carried out in all flaps 72 h after flap elevation. The percentage of surviving skin area of each flap was determined by planimetry 7 days after flap elevation. The mean surviving area of the Group A (control) flaps was 71%, the mean surviving area of the Group B (H2O2-treated) flaps was 72%, the mean surviving area of the Group C (DMSO-treated) flaps was 76%, and that of the Group D (DMSO+H2O2-treated) flaps was 92%. While no statistically significant differences were found between the survival rates of both the flaps treated with H2O2 or DMSO alone and that of the control group, the mean surviving rate of the DMSO+H2O2 treated flaps (+20%) was statistically higher than that of the control flaps. Similarly, a statistically significant difference has been found between the mean PtcO2 values of the DMSO+H2O2 flaps and those of the other three groups of flaps.

Animals↗

PubMed1998

Undermining of the scalp: quantitative effects.

The aim of the present study was to evaluate to what extent undermining affects the closing-tension of scalp defects to quantify the surgery-related benefits provided by this procedure. Data were collected by stepwise loading in 10 patients, 20 scalp flaps (obtained by a reversed Y scalp incision), and three different degrees of subgaleal undermining (1, 5, and 15 cm). The obtained data confirmed the value of undermining to diminish the tension on wound margins when closing a scalp defect. There was a progressive decrease in tension required to advance the wound edge when the amount of undermining was sequentially increased. Most of this reduction occurred with the 5-cm undermining, although statistically the 15-cm undermining also resulted in a significant decrease in the tension required to close the defect. Mean 83.3- and 92.2-percent reductions of the closing tension were obtained with 5 cm and 15 cm of undermining, respectively, compared with that achieved by the 1-cm undermining with the same width of defect.

Adult↗