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1.
Int J Oral Maxillofac Surg ; 49(2): 169-175, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31235388

ABSTRACT

Chronic vascular rejection characterized by the myointimal proliferation of smooth muscle cells that progressively obstruct the arterial graft lumen may become the main cause of long-term graft loss in vascularized composite allotransplantation (VCA), as observed in solid organ transplantation. As such, new diagnostic tools are required. The objective of this study was to evaluate the usefulness of flow magnetic resonance imaging (MRI) in the qualitative and quantitative monitoring of VCA in three patients transplanted between 2005 and 2012. Seven flow MRI acquisitions were performed concurrently with standardized clinical and histological monitoring between 2015 and 2017. A progressive reduction in the average flow rate and intraluminal diameter of the arterial pedicle of the grafts was demonstrated. During follow-up, two patients developed chronic vascular rejection requiring partial resection of the graft. For these patients, flow MRI acquisitions were characterized by a significant reduction in vascular signal, with a reduction in intravascular flow prior to anatomical injury. The results of this study confirm the feasibility of reproducible, non-invasive, and non-operator-dependent morphometric and haemodynamic radiological analysis, providing clinicians with new information on the vascular status of VCA over time and offering the prospect of an imaging technique specific to vascular outflow.


Subject(s)
Graft Rejection , Vascularized Composite Allotransplantation , Humans , Magnetic Resonance Imaging
2.
G Chir ; 38(3): 149-154, 2017.
Article in English | MEDLINE | ID: mdl-29205147

ABSTRACT

AIM: The purpose of this paper is to provide a forensic profile framework of neuromonitoring in thyroid surgery, regarding the information given to the patient and its classification as part of professional liability in the event of recurrent injury. METHOD: Evaluation and reflections on the required behaviour of the surgeon on providing details on the operation before the informed consent is given and to outline the possible legal implications regarding professional liability as a result of recurrent injury. In particular, if it is an obligation to inform the patient about using this method and if it is possible for the surgeon to freely choose whether to employ this method, which is still burdened by a certain percentage of error and for that reason it cannot be defined a "standard of care". RESULTS: To recognize neuromonitoring the role of standard of care in surgery of the thyroid means attribute a role of method able to avoid the surgeon to cause iatrogenic damage to the laryngeal nerve. For the foregoing reasons that is not true, determining false positives and false negatives, and this can be a double edged sword for the surgeon. CONCLUSIONS: Although the progress in the field of thyroid surgery made in the last decade, currently there is no scientific reassuring evidence to completely avoid the possibility of producing an iatrogenic lesion of the laryngeal nerve. Information given to the patient prior to surgery should respect the requirements of completeness, freedom and honesty in order to allow the patient to self-determination.


Subject(s)
Informed Consent/legislation & jurisprudence , Intraoperative Neurophysiological Monitoring , Malpractice/legislation & jurisprudence , Thyroidectomy/legislation & jurisprudence , Humans , Recurrent Laryngeal Nerve Injuries/etiology , Recurrent Laryngeal Nerve Injuries/prevention & control
3.
Am J Transplant ; 17(7): 1935-1940, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28141920

ABSTRACT

Ten years after the first face transplantation, we report the partial loss of this graft. After two episodes of acute rejection (AR) occurred and completely reversed in the first posttransplantation year, at 90 months posttransplantation the patient developed de novo class II donor-specific antibodies, without clinical signs of AR. Some months later, she developed several skin rejection episodes treated with steroid pulses. Despite rapid clinical improvement, some months later the sentinel skin graft underwent necrosis. Microscopic examination showed intimal thickening, thrombosis of the pedicle vessel, and C4d deposits on the endothelium of some dermal vessels of the facial graft. Flow magnetic resonance imaging of the facial graft showed a decrease of the distal right facial artery flow. Three steroid pulses of 500 mg each, followed by intravenous immunoglobulins (2 g/kg), five sessions of plasmapheresis, and three cycles of bortezomib 1.3 mg/m2 , were administered. Despite rescue therapy with eculizumab, necrosis of the lips and the perioral area occurred, which led to surgical removal of the lower lip, labial commissures, and part of the right cheek in May 2015. In January 2016, the patient underwent conventional facial reconstruction because during the retransplantation evaluation a small-cell lung carcinoma was discovered, causing the patient's death in April 2016.


Subject(s)
Facial Transplantation/adverse effects , Graft Rejection/therapy , Postoperative Complications/prevention & control , Adult , Female , Graft Rejection/etiology , Graft Rejection/pathology , Graft Survival , Humans , Immunoglobulins, Intravenous/administration & dosage , Isoantibodies/blood , Plasmapheresis , Prognosis , Reoperation , Time Factors
5.
Am J Transplant ; 12(6): 1541-50, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22390302

ABSTRACT

The use of uncontrolled deceased donors after cardiac arrest (uDDCA) has been developed in France to compensate for organ shortage. The quality of these kidneys remains unclear. We analyzed kidney graft function and histology from 27 uDDCA and compared them with kidneys from 30 extended criteria donors (ECD) and from 24 simultaneous pancreas kidney (SPK) donors as a control group of optimal deceased donors. Kidneys from ECD and SPK donors were preserved by static cold storage while kidneys from uDDCA were preserved by pulsatile perfusion. The uDDCA graft function at 3 years posttransplantation (estimated with MDRD and measured with inulin clearance) did not differ from that of the ECD group (eGFR 44.1 vs. 37.4 mL/min/1.73 m(2) , p = 0.13; mGFR 44.6 vs. 36.1 mL/min/1.73 m(2) , p = 0.07 in the uDDCA and ECD groups, respectively). The histological assessment of 3-month and 1-year protocol biopsies did not show differences for interstitial lesions between the uDDCA and ECD grafts (IF score at M3 was 30 vs. 28% and at M12 36 vs. 33%, p = NS). In conclusion, the results at 3 years with carefully selected and machine-perfused uDDCA kidneys have been comparable to ECD kidneys and encourage continuation of this program and development of similar programs.


Subject(s)
Graft Survival , Kidney Transplantation , Quality of Life , Tissue Donors , Treatment Outcome , Adult , Aged , Female , Humans , Male , Middle Aged
6.
Am J Transplant ; 11(4): 808-16, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21446980

ABSTRACT

Composite tissue allotransplantations (CTAs) have clinically shown little, if any, evidence of chronic rejection. Consequently, the effect of chronic rejection on bones, joints, nerves, muscles, tendons and vessels may still have undescribed implications. We thoroughly assessed all allograft structures by histology, magnetic resonance imaging, ultrasonography and high resolution peripheral quantitative computed tomography scan in four bilateral hand-grafted patients (10, 7, 3 and 2 years of follow-up, respectively) and in one facial allotransplantation (5 years of follow-up). All the recipients presented normal skin structure without dermal fibrosis. Vessels were patent, without thrombosis, stenosis or intimal hyperplasia. Tendons and nerves were also normal; muscles showed some changes, such as a variable degree of muscular hypotrophy, particularly of intrinsic muscles, accompanied by fatty degeneration that might be related to denervation. In the majority of hand-grafted patients graft radius and recipient tibia showed a decrease in trabecular density, although in the graft radius the alterations also involved the cortices. No deterioration of graft function was noted. In these cases of CTA no signs of chronic graft rejection have been detected. However, the possibility that chronic rejection may develop in CTA exists, highlighting the necessity of close continuous follow-up of the patients.


Subject(s)
Face/surgery , Hand Transplantation , Organ Transplantation , Adolescent , Adult , Face/pathology , Female , Follow-Up Studies , Graft Rejection , Graft Survival , Hand/pathology , Humans , Male , Middle Aged , Transplantation, Homologous , Young Adult
7.
Ann Chir Plast Esthet ; 52(5): 424-35, 2007 Oct.
Article in French | MEDLINE | ID: mdl-17905506

ABSTRACT

Hand allograft is a method in the stage of clinical experimentation, which is reserved in France for the treatment of bilateral traumatic amputees. This study reports the Lyon team experience, which is pioneer in this domain. Four patients (3 males and 1 female) underwent seven (one unilateral and three bilateral) hand transplantations from September 1998 to February 2007. The level of amputation was at the wrist or at the mid-forearm. Delay since hand loss ranged from 2.5 to 9 years. The surgical protocol was elaborated and planned case by case. All recipients received the same immunosuppressive treatment. Episodes of acute rejection were observed in the first 3 months after transplantation, which were easily managed after a few days increasing oral prednisone doses and applying topical immunosuppressants. Currently the patients receive the doses of immunosuppressants comparable to those in kidney-grafted patients. We have not registered any severe complication of immunosuppressive treatment up till now (7 years follow-up for the earliest graft). We performed analytical and functional clinical, as well as questionnaire evaluation of patients. The first case (unilateral graft) resulted in graft failure at 2 years due to non-compliance of the patient. The three bilateral graftees demonstrate a favorable evolution despite some immunological (hyperglycemia, serum sickness) and surgical (thrombosis, osteomyelitis, skin loss) complications, which could be managed. The middle and long-term follow-up evaluation revealed good to excellent sensorimotor recovery of 4 hands in both male recipients (4 and 7 years) with satisfactory social adaptation, higher or equal to those expected after post-traumatic replantations at the equivalent level and higher to those obtained with currently available myoelectric prosthesis. The last patient, a young female who has been grafted in February 2007, receives ongoing reeducation course and shows normal progress of functional restoration of both hands. The encouraging results of this clinical experimentation make us currently consider hand allografting as reasonable and useful both for the patients and for evolution of research in composite tissues allotransplantation (CTA). Further long-term careful research and worldwide monitoring of all patients with hand allografts is required to, on the one part, state on the authorization of this surgery, and, on the other part, to better elucidate the mechanisms of successful CTA.


Subject(s)
Hand Transplantation , Plastic Surgery Procedures/methods , Adult , Female , France , Humans , Male , Middle Aged , Transplantation, Homologous
8.
Am J Transplant ; 6(7): 1718-24, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16827876

ABSTRACT

In this study we present our experience concerning bilateral hand transplantation. Two cases were performed: the first in January 2000 and the second in April 2003. Both recipients received the same immunosuppressive treatment, which was similar to those used in solid organ transplantation, including tacrolimus, prednisone and mycophenolate mofetil while antithymocyte globulins were added for induction. Both recipients presented two episodes of acute rejection (maculopapular lesions) in the first 3 months after transplantation; however, these were easily reversed after a few days increasing oral steroid doses and using topical immunosuppressants. The first recipient presented hyperglycemia and serum sickness while the second recipient suffered a thrombosis of the right ulnar artery and an osteomyelitis of left ulna. All the complications were successfully treated. Functional Magnetic Resonance Imaging (fMRI) showed that cortical hand representation progressively shifted from the lateral to the medial region in the motor cortex. After 6 and 2 years respectively, they showed a relevant sensorimotor recovery particularly of sensibility and activity of intrinsic muscles. They were able to perform the majority of daily activities and to lead a normal social life. The first recipient has been working since 2003. They are both satisfied with their grafted hands.


Subject(s)
Hand Injuries/surgery , Hand Transplantation , Adolescent , Adult , Antibodies/immunology , Follow-Up Studies , HLA Antigens/immunology , Hand Injuries/immunology , Humans , Male , Time Factors
9.
Diabet Med ; 23(6): 654-9, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16759308

ABSTRACT

AIMS: The aim was to investigate pancreatic B-cell function and insulin sensitivity in simultaneous pancreas-kidney (SPK) recipients with systemic or portal venous drained pancreas allograft using simple and easy tests. METHODS: The study included 44 patients with Type 1 diabetes and end-stage renal disease who had undergone SPK transplantation: 20 recipients received a pancreas allograft with systemic venous drainage (S-SPK) and 24 with portal venous drainage (P-SPK). We studied only recipients with functioning grafts, with normal serum glucose, HbA(1c) and serum creatinine values, on a stable drug regimen. The subjects were studied at 6, 12, 24, 36, 48 and 60 months after transplantation. Insulin sensitivity and B-cell function indices were derived from blood samples and oral glucose tolerance tests. RESULTS: All patients from both groups had normal fasting glucose, body mass index and HbA(1c) values by selection. The homeostatic model (HOMA) beta-cell index was significantly lower in P-SPK recipients at several points of the follow-up. HOMA-IR was significantly higher in S-SPK recipients at 6 and 24 months after transplantation and was positively correlated with fasting insulin values, but never exceeded 3.2. There was no significant difference in QUICKI index values between the two groups. Although all patients from both groups always had normal glucose tolerance, the area under the insulin curve was higher in the S-SPK group. Cholesterol, low-density lipoprotein-cholesterol and triglycerides were higher in the P-SPK group. CONCLUSIONS: The results suggest sustained long-term endocrine function in both groups and show that portal venous drainage does not offer major metabolic advantages.


Subject(s)
Diabetes Mellitus, Type 1/metabolism , Kidney Failure, Chronic/metabolism , Kidney Transplantation , Pancreas Transplantation , Pancreas/blood supply , Portal Vein , Adult , Area Under Curve , Cholesterol/blood , Cholesterol, LDL/blood , Diabetes Mellitus, Type 1/surgery , Female , Follow-Up Studies , Glucose Tolerance Test , Homeostasis , Humans , Insulin/blood , Insulin Resistance , Insulin-Secreting Cells/metabolism , Kidney Failure, Chronic/surgery , Male , Transplantation, Homologous , Triglycerides/blood
10.
Transplant Proc ; 37(1): 308-11, 2005.
Article in English | MEDLINE | ID: mdl-15808627

ABSTRACT

The University of Wisconsin (UW) solution is the most commonly used preservation solution. However, a new preservation solution-IGL-1-contains an inversion of K and Na concentrations and substitution of polyethylene glycol for hydroxyethyl starch in the UW solution. The present study is the first clinical experience on the outcome of kidneys preserved in IGL-1 solution. From June 2003 to June 2004, 119 cadaveric kidneys were retrieved and stored in IGL-1 solutions; among the 119 organs, this study includes 37 IGL-1-preserved kidneys that were locally transplanted versus 33 kidneys stored in University of Wisconsin (UW) solution that were also locally transplanted. The groups were comparable with regard to donor and recipient characteristics. Renal function outcome was evaluated by comparing delayed graft function (DGF) rates, the evolution of serum creatinine, daily urine output, and creatinine clearance. Biopsies were performed after reperfusion to evaluate apoptosis. The incidence of DGF was 5.71% among IGL-1 kidneys and 13.79% among UW kidneys. Creatinine values were significantly lower among the IGL-1 group from 2 to 14 days postoperative and at 1 month. Daily urinary output did not show any significant differences between the two groups. IGL-1 kidneys had a superior creatinine clearance during the first 15 postoperative days compared to UW kidneys. Kidneys preserved in IGL-1 solution showed fewer apoptotic cells compared to kidneys preserved in UW solution. This preliminary report suggests a superiority of IGL-1 for the immediate outcome of transplanted kidneys.


Subject(s)
Kidney Transplantation/physiology , Kidney , Organ Preservation Solutions , Adenosine , Adult , Allopurinol , Cadaver , Female , Glutathione , Humans , Insulin , Male , Polyethylene Glycols , Potassium , Raffinose , Sodium , Tissue Donors , Treatment Outcome
11.
Acta Chir Belg ; 104(3): 266-71, 2004 Jun.
Article in English | MEDLINE | ID: mdl-15285535

ABSTRACT

Composite tissue allograft has become a clinical reality: hands, vascularized femoral diaphyses, abdominal walls, a larynx have all been transplanted throughout the world. Conventional immunosuppressive protocol has shown to be sufficient and effective. Rejection has been prevented in most cases and when it did occur it was successfully reversed. Skin has been confirmed as the principal target of acute and chronic rejection. There has been no mortality or early graft losses and, particularly in hand transplantation, the survival graft rate is 91% with a follow-up period ranging from 6 months to 61 months. The side effects of immunosuppression are limited and include primarily transient hyperglycemia, an increase in creatinine values and some opportunistic infections (i.e. cytomegalovirus infection). Nerve regeneration and cortical reorganization have been demonstrated in hand transplantation. Functional results have been encouraging particularly for hand and larynx transplantation. Appropriate indications and patient selection, based particularly on patient motivation and compliance, are essential requirements for composite tissue allograft success.


Subject(s)
Hand Transplantation , Tissue Transplantation/methods , Humans
12.
Transplant Proc ; 36(3): 664-8, 2004 Apr.
Article in English | MEDLINE | ID: mdl-15110626

ABSTRACT

Hand transplantation may become an important procedure for upper limb functional restoration. To date, 18 patients have been undergone 24 hand operations in the world. Initial results are extremely promising; the functional results are apparently superior to those obtained with prostheses. We report on the combined French and Italian experience of six patients (eight hands), which is based on a jointly devised protocol and represents the largest available clinical series. Six male patients aged 43, 33, 35, 32, 33, and 22 years received either a single right hand-dominant transplantation (four cases) or a simultaneous double hand transplantation (two cases). The time since the amputation ranged from 3 to 22 years. The level of transplantation was at the wrist in five cases (six hands) and at the distal forearm in two cases (two hands). Cold ischemia averaged 11.5 hours. Three patients simultaneously received additional full-thickness skin taken from the donor and transplanted onto their left hip area. This skin served as a source for biopsies and as an additional area to monitor rejection (distant sentinel skin graft). The immunosuppressive protocol included polyclonal antibodies (three patients) or monoclonal anti-CD 25 antibody (three patients), tacrolimus, mycophenolate mofetil, and prednisolone. No surgical complications occurred. Skin rejection occurred at least once in all patients at a mean of 40 days postoperatively. Three patients recovered protective and some discriminative sensation in their palm and fingers. Two patients are recovering sensation, but are still in the early phases of the regenerative process, due to the short time since the transplantation. One patient was not compliant with the immunosuppressive therapy, and underwent uncontrolled rejection and reamputation.


Subject(s)
Hand Transplantation , Adolescent , Adult , Cadaver , Humans , Magnetic Resonance Imaging , Middle Aged , Tissue Donors , Transplantation, Homologous/methods , Treatment Outcome
14.
Ann Chir ; 127(1): 19-25, 2002 Jan.
Article in French | MEDLINE | ID: mdl-11833300

ABSTRACT

AIM OF THE STUDY: The previous results achieved in single hand transplantations confirmed the feasibility of this procedure and encouraged us to perform the first human double hand transplantation, which was performed in January 2000. In the present study we reported the results obtained eighteen months after transplantation. PATIENT AND METHODS: The recipient was a 33-year old man suffering from a traumatic amputation of both hands in 1996. Surgery included procurement of the upper extremities from a 18-year old multiorgan cadaveric donor, preparation of the graft and recipient's stumps, transplantation of the hands, which included bone fixation, arterial and venous anastomoses, nerve suture, joining of tendons and muscles, and skin closure. Immunosuppressive protocol included tacrolimus, prednisone and mycophenolate mofetil. An intensive rehabilitation program was performed. Follow-up included immunological tests, skin biopsies, arteriography, bone scintigraphy, electromyography and brain functional magnetic resonance imaging. RESULTS: No surgical complications, infectious complications and graft-versus-host-disease occurred. Two episodes of acute skin rejection were demonstrated and they were completely reversed increasing steroid dose. Nerve regeneration and cortical reorganization were shown. Sensorimotor recovery was encouraging and life quality improved. CONCLUSION: This double hand transplantation showed that conventional immunosuppressive protocol is effective and safe as well as that functional results are at least as good as those achieved in replanted upper extremities.


Subject(s)
Amputation, Traumatic/surgery , Hand Injuries/surgery , Hand Transplantation , Immunosuppressive Agents/therapeutic use , Adult , Anastomosis, Surgical/methods , Biopsy , Cadaver , Cerebral Cortex , Graft Survival , Humans , Magnetic Resonance Imaging , Male , Motor Skills , Nerve Regeneration , Postoperative Complications , Surgical Flaps , Treatment Outcome
15.
J Urol ; 166(5): 1915-9, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11586260

ABSTRACT

PURPOSE: We established a primate model to investigate the effects of the antileukocyte function associated antigen 1 (CD 11a) mAb odulimomab (Imtix-Sangstad, Lyon, France) for preventing renal ischemia-reperfusion injury. MATERIALS AND METHODS: We randomly divided 34 Macaca cynomolgus monkeys into groups 1 and 2, which received a renal autograft after 2 hours of cold ischemia, and groups 3 and 4, which received the autograft after 24 hours of cold ischemia. Before cold ischemia all harvested kidneys were subjected to 30 to 45 minutes of warm ischemia. Groups 1 and 3 monkeys were treated with an antileukocyte function associated antigen 1 mAb before cold ischemia and then for 3 days, while groups 2 and 4 monkeys received an IgG1 isotype control. In all groups renal function was investigated before warm ischemia and 72 hours after reperfusion. Serum creatinine and the leukocyte count were determined daily. Histological studies were done and lactoferrin was measured in the autotransplanted kidney 72 hours after reperfusion. RESULTS: A decrease in renal function was shown after 2 hours of cold ischemia with tubular necrosis and mild cell infiltration, while after 24 hours of cold ischemia there was severe renal failure with tubular and glomerular necrosis, and leukocyte infiltration. A significant improvement in renal function and decrease in kidney lactoferrin content was evident in group 1 compared to group 2 at 72 hours, while no significant difference was noted in groups 3 and 4. No difference in histological patterns was evident in treated and untreated animals. CONCLUSIONS: This study provides evidence for the validity of this ischemia-reperfusion injury model in primates. The protective effects of antileukocyte function associated antigen 1 mAb on renal injury was not as dramatic as in rodent models but a significant improvement in renal function was observed in treated animals after 2 hours of cold ischemia.


Subject(s)
Antibodies, Monoclonal/therapeutic use , Disease Models, Animal , Kidney Transplantation , Kidney/blood supply , Lymphocyte Function-Associated Antigen-1/therapeutic use , Reperfusion Injury/prevention & control , Animals , Antibodies, Monoclonal/pharmacology , Haplorhini , Kidney/drug effects , Lymphocyte Function-Associated Antigen-1/pharmacology , Macaca fascicularis , Random Allocation
16.
Cell Mol Life Sci ; 58(8): 1113-20, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11529503

ABSTRACT

Cholesterol esterification and smooth muscle cell (SMC) proliferation are the crucial events in the development of atherosclerotic lesions. The objective of this study was to analyse cholesterol esterification and the expression of MDR1 (multidrug resistance), ACAT (acyl-CoA:cholesterol acyltransferase) and caveolin-1 genes in atherosclerotic and healthy vascular walls, in SMCs obtained from atherosclerotic lesions and saphenous veins. Results demonstrated higher levels of cholesterol esters, ACAT and MDR1 mRNAs and lower levels of caveolin-1 mRNA in atherosclerotic segments compared to adjacent serial sections of the same artery and the corresponding non-atherosclerotic arteries from cadaveric donors. SMCs isolated from atherosclerotic plaques manifested an increased capacity to esterify cholesterol and to grow at a faster rate than SMCs isolated from saphenous veins. In addition, when SMCs from atherosclerotic plaques were cultured in the presence of progesterone, a potent inhibitor of cholesterol esterification, significant growth suppression was observed. An increase in ACAT and MDR1 expression and a concomitant decrease in caveolin-1 expression were also observed in SMCs isolated from atherosclerotic arteries as early as 12 h after serum stimulation. An opposite pattern was found when SMCs were treated with progesterone. These findings support the idea that cholesterol esterification plays a role both in early atherogenesis and in clinical progression of advanced lesions and raise the possibility that the cholesterol ester pathway might directly modulate the proliferation of SMCs.


Subject(s)
ATP Binding Cassette Transporter, Subfamily B, Member 1/genetics , Arteriosclerosis/metabolism , Caveolins/genetics , Gene Expression , Muscle, Smooth, Vascular/cytology , Adult , Aged , Arteriosclerosis/pathology , Caveolin 1 , Cell Division , Cells, Cultured , Cholesterol Esters/metabolism , Female , Humans , Lipid Metabolism , Male , Middle Aged , Reverse Transcriptase Polymerase Chain Reaction , Sterol O-Acyltransferase/genetics , Time Factors
17.
Pancreas ; 23(1): 68-71, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11451150

ABSTRACT

Several studies have shown that pituitary adenylate cyclase activating polypeptide (PACAP) stimulates at very low concentration insulin release from pancreatic beta cells. In addition, PACAP has been evidenced in pancreatic nervous fibers surrounding the islets, the core of the islet, and the capillaries. The aim of the present study was to demonstrate internalization of PACAP in pancreatic islet cells. Pancreatic islets were obtained from Wistar rat pancreata by modified Lacy's isolation method. The isolated islets were incubated in the presence of Fluo-PACAP 27, a fluorescent ligand specific for PACAP receptors. At the end of incubation the islets were fixed in paraformaldehyde and then observed by confocal microscope. Fluo-PACAP 27 was internalized into pancreatic islet cells, and this process was time- and temperature-dependent (37 degrees C). The fluorescent molecules converged toward the nucleus where an intense fluorescence was evidenced after 60 minutes. Incubation with phenyl arsine oxide as well as with PACAP 6-38, a receptor antagonist, prevented the internalization process. Further studies are required to explain the internalization process of PACAP 27 into the nucleus of pancreatic islet cells.


Subject(s)
Islets of Langerhans/chemistry , Neuropeptides/analysis , Animals , Arsenicals/pharmacology , Cell Compartmentation , Cell Nucleus/chemistry , Cell Nucleus/ultrastructure , Cell Separation , Endocytosis , Image Processing, Computer-Assisted , Islets of Langerhans/ultrastructure , Male , Microscopy, Confocal , Microscopy, Fluorescence , Pituitary Adenylate Cyclase-Activating Polypeptide , Rats , Rats, Wistar , Specimen Handling
18.
Eur J Vasc Endovasc Surg ; 22(1): 31-6, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11461099

ABSTRACT

OBJECTIVES: a positive correlation between cholesterol esterification, acyl-CoA:cholesterol acyltransferase (ACAT), multidrug resistance (MDR1) gene expression and atherosclerotic lesions has been shown in human arteries. The objective of this study was to map the expression of MDR1, ACAT genes and the cholesteryl ester content in normal, atherosclerotic and varicose human vessels. MATERIALS: vascular segments were obtained from seven cadaveric donors, 27 patients undergoing vascular surgery for severe atherosclerotic disease and 11 patients with saphenous vein varicosities. METHODS: lipid analysis and RT-PCR of MDR1 and ACAT mRNAs were performed. RESULTS: an increase in cholesteryl ester content and in ACAT and MDR1 expression was demonstrated in relation to the age in the arteries prone to atherosclerosis; this expression was maximal in arteries from symptomatic patients. In resistant arteries and in veins cholesteryl ester accumulation was rare and light, while ACAT and MDR1 expression was not related to the age of the subjects. CONCLUSIONS: the results showed that an increase in MDR1 and ACAT expression may be responsible for the accumulation of cholesteryl esters as well as for cell growth rate acceleration in vessel sites prone to atherosclerosis.


Subject(s)
Arteriosclerosis/metabolism , Cholesterol Esters/metabolism , ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism , Adult , Aged , Aorta, Abdominal/metabolism , Carotid Artery, Common/metabolism , Female , Femoral Artery/metabolism , Humans , Iliac Artery/metabolism , Male , Mammary Arteries/metabolism , Middle Aged , Reverse Transcriptase Polymerase Chain Reaction , Sterol O-Acyltransferase/metabolism
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