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ABSTRACT: Dialysis patients requiring valve surgery have high morbidity and mortality rates. Although elevated serum parathyroid hormone (PTH) levels are associated with increased mortality in dialysis patients, this correlation has not been investigated in patients undergoing cardiac valve operations. This study assesses the impact of PTH levels on mortality in dialysis patients undergoing valve operations.
A retrospective analysis of 109 dialysis patients undergoing valve operation with preoperative PTH levels between 1996 and 2007 at a US academic center was performed. Cox regression analyses were done using PTH as a binary variable. The patients were followed from the date of the operative procedure until death or loss to follow-up.
Higher mortality risk was seen once preoperative PTH exceeded 200 pg/mL (hazard ratio [HR], 3.43; P = .003). Mean survival was improved in the PTH < 200 pg/mL group when compared with the PTH ≥ 200 pg/mL group (86.7 vs 40.3 months, respectively). Other independent predictors of mortality included serum phosphate (HR, 1.20; P = .017), calcium-phosphate product (HR, 1.02; P = .038), and history of myocardial infarction (HR, 2.12; P = .015).
Preoperative PTH level ≥ 200 pg/mL is predictive of increased mortality after valve surgery among dialysis patients. Hyperparathyroidism should be investigated further as a possible modifiable risk factor for postoperative mortality in this high-risk patient cohort.
Surgery 12/2011; 150(6):1095-101. · 3.10 Impact Factor
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ABSTRACT: The long-term metabolic function of microencapsulated xenogeneic adult porcine islets (API) was assessed in a murine model of type 1 diabetes mellitus.
API were encapsulated in barium-gelled alginate and transplanted intraperitoneally in diabetic nonobese diabetic (NOD) mice given no immunosuppression or given costimulatory blockade (CoB; CTLA4-Ig+anti-CD154 mAb). Control mice received nonencapsulated API under the kidney capsule. Graft function was monitored by measurement of random blood glucose levels, serum glycosylated hemoglobin (HbA1c), serum porcine C peptide, in vivo glucose tolerance tests, and histologic analyses of host pancreas and graft biopsies. Host immune responses to the islet xenografts were characterized by phenotyping peritoneal cellular infiltrates and by measuring serum antiporcine antibody levels.
Without immunosuppression, nonencapsulated API functioned for less than 1 week, and microencapsulated API functioned for 35+/-14 days before rejection, associated with both a cellular and a humoral immune response. With continuous CoB, nonencapsulated API functioned for 27+/-4 days, whereas microencapsulated API functioned for >450 days with measurable levels of serum porcine C peptide, near normal in vivo glucose tolerance tests and HbA1c levels, and intact microcapsules containing viable, insulin-positive porcine islets.
Microencapsulated API restored normoglycemia for more than 1 year in spontaneously diabetic NODs given dual CoB. To our knowledge, this is the first study to document long-term normalized HbA1c, porcine C peptide, and near normal glucose tolerance in immunosuppressed diabetic NOD mice transplanted intraperitoneally with microencapsulated API. Our study suggests that transplantation of microencapsulated porcine islet xenografts may be a future treatment for patients with type 1 diabetes mellitus.
Transplantation 08/2009; 88(2):160-9. · 4.00 Impact Factor
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ABSTRACT: Isolated familial hyperparathyroidism (FHPT) not associated with multiple endocrine neoplasia is a rare and aggressive form of primary hyperparathyroidism. The traditional management of FHPT is a bilateral neck exploration with an increased rate of multigland hyperplasia, supernumerary glands, and recurrence. A prospective database was queried, which included 1383 consecutive parathyroidectomies between 1992 and 2008, and 28 patients with FHPT were identified. Patient demographics, pathology, intraoperative parathyroid hormone (IOPTH) kinetics, recurrence patterns, and accuracy of localization studies were analyzed. Twenty-one patients underwent bilateral neck explorations as an initial surgery, and seven patients had nine unilateral neck explorations for recurrent hyperparathyroidism. Overall cure rate was 89.2 per cent with a mean follow-up of 2.9 years (range: 6 months to 9.2 years); 64.3 per cent of patients had multigland disease. IOPTH helped identify supernumerary glands in three (12.5%) patients and accurately lateralized recurrent disease in eight of nine surgeries (88.8%). Tc-99m-Sestamibi failed to identify multigland disease in 11 patients (52.3%). FHPT has a greater prevalence of multigland disease, decreased utility of sestamibi scanning, and a higher recurrence rate than sporadic primary hyperparathyroidism. In FHPT, IOPTH is a useful adjunct in identifying additional tumors and in select cases may play a role in tumor localization.
The American surgeon 08/2009; 75(7):579-82; discussion 582-3. · 1.28 Impact Factor
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ABSTRACT: If alginate microcapsules are to be used clinically for therapeutic cell transplants, capsule formulations must be designed to enhance optimal biocompatibility and immune acceptance.
Microcapsules were generated using highly purified, endotoxin-free, ultra-low viscosity, high mannuronic acid alginate. The capsules differed with respect to gelling cation (50 mM barium or 100 mM calcium), alginate concentration (2.0% or 3.3%), alginate density (homogeneous or inhomogeneous), and the presence or absence poly-L-lysine (PLL) coating. Four types of empty capsules were implanted intraperitoneally (i.p.) in normal NOD mice, and their biocompatibility was evaluated after various time periods in vivo. Encapsulated adult porcine islets (APIs) were transplanted i.p. in diabetic NOD mice, and immune acceptance was evaluated by graft survival times, host cell adherence to capsule surfaces, and flow cytometric analysis of peritoneal host cells.
All empty alginate capsules were biocompatible in vivo, but barium-gelled alginate capsules without PLL were clearly the most biocompatible, since 99% of these empty capsules had no host cell adherence up to 9 months in vivo. In diabetic NOD mice, APIs functioned significantly longer in barium-alginate capsules without PLL than in calcium-alginate capsules with PLL and had strikingly less host cell adherence, although large numbers of host cells (predominantly macrophages and eosinophils) infiltrated the peritoneal cavities of recipients with APIs in both types of capsules. Addition of PLL coatings to barium-alginate capsules dramatically decreased graft survival.
Inhomogeneous barium-gelled alginate capsules without PLL are the optimal candidates for clinical trials, based on their enhanced biocompatibility and immune acceptance in vivo.
Journal of diabetes science and technology 09/2008; 2(5):760-7.
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ABSTRACT: Routine use of intraoperative parathyroid hormone (IOPTH) has been challenged in both unilateral/limited (LE) and bilateral exploration (BE). To investigate this, we assessed the usefulness of IOPTH in surgical management of primary hyperparathyroidism and parathyroid carcinoma (PC).
Between 1998 and 2006, 1133 patients were explored for hyperparathyroidism: 185 LE, 743 BE with IOPTH, 95 BE without IOPTH, 110 reoperations, and 4 PCs. IOPTH patterns were correlated with parathyroid pathology (single adenoma [SA] or multigland disease [MGD]) and operative success.
In LE, IOPTH returned to normal in 78% of patients; all patients had SA, and 99% were cured at a mean +/- SEM of 1.2 +/- .24 years; 22% of LE patients (n = 41) whose IOPTH did not return to normal were converted to BE, and all had MGD. BE with and without IOPTH was equally successful 97% and 98% (P = NS) of the time, respectively. In BE in which IOPTH did not return to normal, 9% of patients remained hypercalcemic; tumor distribution mirrored other BE patients (75% SA, 25% MGD). In reoperations, a normal final IOPTH correlated with cure in 99%; otherwise, 59% had persistent disease. Differential bilateral internal jugular vein IOPTH sampling lateralized disease in 77% of reoperations.
IOPTH is an important adjunct for successful LE by identifying the presence of MGD and avoiding operative failure. IOPTH adds little to BE; however, final IOPTH values may predict persistent disease in BE, reoperations, and PCs.
Annals of Surgical Oncology 03/2008; 15(2):493-8. · 4.17 Impact Factor
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ABSTRACT: In the setting of renal disease and hyperparathyroidism, a near total parathyroidectomy with cryopreservation is a safe and
effective treatment. Even with improved dialysis and medical management, parathyroid surgery remains effective therapy for
patients with hyperparathyroidism associated with renal failure. Symptomatic patients particularly need to be identified earlier
for parathyroidectomy to prevent progression of bone disease in chronic renal failure.
Clinical Reviews in Bone and Mineral Metabolism 05/2007; 5(2):103-107.
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ABSTRACT: The cell membrane establishes an important paradigm for the molecular engineering of coatings for implantable devices because of its intrinsic biocompatibility and ability to act as a template for the assembly of diverse membrane-associated macromolecules. A stabilized membrane-mimetic film was assembled on alginate/Ca(2+) hydrogel microcapsules by in situ polymerization of an acrylate functionalized phospholipid. The phospholipid monomer was prepared as unilamellar vesicles and fused onto octadecyl chains that were components of an amphiphilic terpolymer anchored onto a polyelectrolyte multilayer (PEM) by electrostatic interactions. Microcapsules coated with a membrane-mimetic film were implanted into the peritoneal cavity of C57BL/6 mice, and the short-term biostability and biocompatibility of membrane-mimetic films assembled on two different alginate/poly(l-lysine) PEM cushions were compared. The nature of the underlying PEM support had a profound impact on the biocompatibility of the membrane-mimetic film, as the percentage of retrieved microcapsules completely overgrown with host cells shifted from 66+/-5.9% to less than 1% when modifications to the PEM were made. When assembled on the appropriate PEM support, biocompatibility of membrane-mimetic-coated microspheres was high wherein 87.5+/-5.7% of the implanted microspheres were retrieved 4 weeks after implantation and 92.6+/-6.4% of the retrieved capsules were free of cell adhesion or fibrotic overgrowth. Finally, 4 weeks after implantation, microspheres coated with a Texas red-labeled membrane-mimetic film were imaged with confocal microscopy and exhibited a uniform film around the periphery of the implant, indicating a high degree of film biostability. Hence, membrane-mimetic films provide a new route for generating robust, biocompatible, and biochemically heterogeneous coatings for implantable devices through molecular self-assembly.
Biomaterials 03/2007; 28(4):609-17. · 7.40 Impact Factor
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ABSTRACT: To determine the utility of available radionuclide imaging modalities for preoperative parathyroid localization, we compared the accuracy of 4 types of technetium-99m ((99)Tc) sestamibi-based scans.
Over 5 years, 833 patients with sporadic primary hyperparathyroidism underwent either (99)Tc-sestamibi with planar views (Planar; n = 138); sestamibi single photon emission computed tomography (SPECT; n = 165); SPECT with thyroid (123)I-subtraction phase (SPECT/(123)I; n = 350); or SPECT combined with conventional CT (SPECT/CT; n = 180). The accuracy of each modality was determined on the basis of intraoperative parathyroid pathology, defined as single adenoma or multigland disease.
Planar scans had significantly more false negatives (no tumor visualized) than SPECT-based scans (P < 0.01), but positive predictive values were similar. A false-negative scan was present in 38% of Planar scans, 27% SPECT, 4% SPECT/(123)I, and 17% SPECT/CT, with single adenoma found at operation in 77%, 64%, 53%, and 74%, respectively. When a scan had a single focus of uptake, SA was found at that location in 77%, 85%, 68%, and 87%, respectively. SPECT, SPECT/(123)I, and SPECT/CT did not significantly reduce the false-positive rate.
We recommend obtaining multiplanar SPECT-based imaging, which offers 3-dimensional localization and improved detection of parathyroid tumors when compared with Planar scans. A negative scan did not predict multigland disease.
Surgery 12/2006; 140(6):856-63; discussion 863-5. · 3.10 Impact Factor
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Kenneth Cardona,
Gregory S Korbutt,
Zvonimir Milas,
James Lyon,
Jose Cano,
Wanhong Jiang,
Hameeda Bello-Laborn,
Brad Hacquoil,
Elizabeth Strobert,
Shivaprakash Gangappa, Collin J Weber,
Thomas C Pearson,
Ray V Rajotte,
Christian P Larsen
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ABSTRACT: We evaluated the ability of neonatal porcine islets to engraft and restore glucose control in pancreatectomized rhesus macaques. Although porcine islets transplanted into nonimmunosuppressed macaques were rapidly rejected by a process consistent with cellular rejection, recipients treated with a CD28-CD154 costimulation blockade regimen achieved sustained insulin independence (median survival, >140 days) without evidence of porcine endogenous retrovirus dissemination. Thus, neonatal porcine islets represent a promising solution to the crucial supply problem in clinical islet transplantation.
Nature Medicine 04/2006; 12(3):304-6. · 22.46 Impact Factor
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ABSTRACT: Our goal is to develop effective islet grafts for treating type 1 diabetes. Since human islets are scarce, we evaluated the efficacy of a microencapsulated insulin-secreting conditionally transformed allogeneic beta-cell line (betaTC-tet) in non-obese diabetic mice treated with tetracycline to inhibit cell growth. Relatively low serum levels of tetracycline controlled proliferation of betaTC-tet cells without inhibiting effective control of hyperglycemia in recipients. There was no significant host cellular reaction to the allografts or host cell adherence to microcapsules, and host cytokine levels were similar to those of sham-operated controls. We conclude that encapsulated allogeneic beta-cell lines may be clinically relevant, because they effectively restore euglycemia and do not elicit a strong cellular immune response following transplantation. To our knowledge, this is the first extensive characterization of the kinetics of host cellular and cytokine responses to an encapsulated islet cell line in an animal model of type 1 diabetes.
Biochemical and Biophysical Research Communications 03/2006; 340(1):236-43. · 2.48 Impact Factor
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ABSTRACT: Some have suggested that thyroid disease is even more prevalent among patients with hyperparathyroidism (HPT) than in the general population. We sought to define the incidence and optimal management strategies of thyroid disease in patients undergoing surgery for HPT.
Clinical characteristics were reviewed for 1200 consecutive HPT patients treated at two endocrine surgery referral centers from 1992-2003. Both centers practice bilateral neck exploration, and one routinely obtains preoperative neck ultrasound (US) performed by surgeons.
Forty percent (477/1195) of HPT patients had coexisting thyroid disease, whether identified at parathyroidectomy (39%; 327/845) or by US (43%; 150/350). Colloid nodules/goiters accounted for nearly half of thyroid pathology, followed by follicular adenomas, papillary cancer, thyroiditis, and intrathyroidal parathyroids. Thyroid malignancy was found in 4.6% of HPT patients versus less than 1% in autopsy reports. Thyroid pathology was similar among single adenomas, multigland, and renal HPT. Unexpected thyroid disease first encountered at parathyroidectomy required partial or total thyroidectomy in 30% (257/845). US-detected thyroid nodules prompted fine-needle biopsy in 20%, which was cost effective in limiting concomitant thyroid surgery to fewer patients (6%; 21/350). Overall low incidence (<0.5%) of persistent/recurrent HPT, nerve injury, and neck hematoma was unaffected by thyroid abnormalities.
The high prevalence of thyroid disease, especially malignancies, among HPT patients mandates vigilant diagnosis and preparation for possible simultaneous parathyroid-thyroid surgery. Without appropriate preoperative screening, focal explorations for HPT may be prone to delayed diagnosis of thyroid tumors. Ultrasound performed by surgeons or endocrinologists preoperatively is an excellent diagnostic tool and minimizes unnecessary thyroidectomy in patients with subclinical thyroid disease.
Thyroid 09/2005; 15(9):1055-9. · 4.79 Impact Factor
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ABSTRACT: Transplantation of human islets has been successful clinically. Since human islets are scarce, we are studying microencapsulated porcine islet xenografts in nonobese diabetic (NOD) mice. We have evaluated the cellular immune response in NOD mice with and without dual costimulatory blockade.
Alginate-poly-L-lysine-encapsulated adult porcine islets were transplanted i.p. in untreated diabetic NODs and NODs treated with CTLA4-Ig to block CD28/B7 and with anti-CD154 mAb to inhibit CD40/CD40-ligand interactions. Groups of mice were sacrificed on subsequent days; microcapsules were evaluated by histology; peritoneal cells were analyzed by FACS; and peritoneal cytokines were quantified by ELISA. Controls included immunoincompetent NOD-Scids and diabetic NODs given sham surgery or empty microcapsules.
Within 20 days, encapsulated porcine islets induced accumulation of large numbers of macrophages, eosinophils, and significant numbers of CD4 and CD8 T cells at the graft site, and all grafts were rejected. During rejection, IFNgamma, IL-12 and IL-5 were significantly elevated over sham-operated controls, whereas IL-2, TNFalpha, IL-4, IL-6, IL-10, IL-1beta and TGFbeta were unchanged. Treatment with CTLA4-Ig and anti-CD154 prevented graft destruction in all animals during the 26 days of the experiment, dramatically inhibited recruitment of host inflammatory cells, and inhibited peritoneal IFNgamma and IL-5 concentrations while delaying IL-12 production.
When two different pathways of T cell costimulation were blocked, T cell-dependent inflammatory responses were inhibited, and survival of encapsulated islet xenografts was significantly prolonged. These findings suggest synergy between encapsulation of donor islets and simultaneous blockade of two host costimulatory pathways in prolonging xenoislet transplant survival.
Transplantation 03/2005; 79(4):409-18. · 4.00 Impact Factor
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ABSTRACT: Despite several options for the extent of parathyroidectomy in secondary and tertiary hyperparathyroidism, <5% of patients are referred for surgical procedures. The purpose of this study was to identify beneficial outcomes of near-total parathyroidectomy (NTPTX) in this population.
NTPTX (a vascularized parathyroid remnant is left in situ, and cryopreservation is performed) was completed in 142 patients with secondary (n = 93 patients) and tertiary (n = 49 patients) hyperparathyroidism, and was guided by intraoperative intact PTH (IOPTH).
One hundred thirty-six of 142 patients (96%) remain cured at a mean follow-up time of 23 +/- 26 months. Six patients had missed mediastinal (n = 4 patients) or cervical (n = 2 patients) parathyroid glands. No patient required re-resection of a cervical parathyroid remnant. One patient had hypoparathyroidism and underwent autografting with cryopreserved tissue. NTPTX reduced parathyroid mass (4526 +/- 4515 mg to 77 +/- 56 mg) and IOPTH (1171 +/- 1252 pg/mL to 101 +/- 127 pg/mL). Fatigue and musculoskeletal pain resolved promptly after operation. Patients with tertiary hyperparathyroidism experienced an improvement in bone density of 3.6% per year. NTPTX achieved full healing of extremity ulcers without amputations or perioperative death in 22 patients with calciphylaxis.
NTPTX effectively treats secondary and tertiary hyperparathyroidism in >95% patients. IOPTH monitoring and cryopreservation are valuable procedural adjuncts. Limb salvage in calciphylaxis, symptomatic relief, and improved bone density are substantial benefits to recommend this procedure to patients with renal hyperparathyroidism.
Surgery 01/2005; 136(6):1252-60. · 3.10 Impact Factor
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ABSTRACT: Laparoscopy has been reported advantageous over the conventional open technique for adrenalectomy. However, most comparative series include the relatively more challenging cases in the open group. The aim of this study is to assess the actual role of laparoscopy in reducing perioperative complications compared to open surgery in patients undergoing adrenalectomy. Between January 1992 and December 2002, we performed 148 adrenalectomies in 138 patients. Depending on the approach, patients were divided into laparoscopic (LA) or open adrenalectomy (OA) groups. Demographics, tumor characteristics, operative data, and outcomes were analyzed. Linear and logistic regressions identified factors influencing perioperative outcomes. Multivariate-adjusted logistic regression assessed independent relationship between factors and perioperative outcomes. A total of 78 cases were performed laparoscopically and 70 open. Patients were matched for age and sex. Tumor size was smaller (3 +/- 2 vs 5 +/- 3 cm), operative time was shorter (133 +/- 65 vs 165 +/- 100 min), estimated blood loss was less (114 +/- 152 vs 350 +/- 417 cc), length of stay was shorter (3 +/- 2 vs 7 +/- 3 days), and overall complication rate was lower (7% vs 20%) in the LA compared to the OA group. The incidence of cancer in tumors > or = 6 cm (31%) was higher than in those < 6 cm (4%). All patients with cancer underwent OA. LA was the only factor independently associated with a decreased likelihood of intraoperative bleeding and postoperative pulmonary complications. Large and malignant adrenal tumors are more frequently removed through an open approach. However, this fact has no influence on the advantages of the LA over the OA. Laparoscopy reduces perioperative adrenalectomy perioperative complication rates. It has a positive impact on intraoperative bleeding and postoperative pulmonary complications.
The American surgeon 08/2004; 70(8):668-74. · 1.28 Impact Factor
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ABSTRACT: A double adenoma (DA) is a recognized clinical entity of primary hyperparathyroidism (HPT) and is presumed to have uniform location distribution. We reviewed our experience with 2-gland parathyroid disease to identify anatomic patterns and implications for surgical management.
Clinical characteristics were reviewed for 828 consecutive patients with HPT at 2 endocrine referral centers that practice bilateral neck exploration with intraoperative parathyroid hormone (IOPTH) measurement.
Fifteen percent (127 of 828) of HPT patients demonstrated 2 enlarged glands; 13% (107 of 828), 3- or 4-gland hyperplasia; and 71% (592 of 828), single adenomas. DAs in superior parathyroids affected 57 of 127 (45%) patients, an observed frequency 3-fold higher than expected (P<.001, chi-square test). DAs were larger than normal glands (240+/-575 mg vs 28+/-23 mg, P<.001), and superior parathyroid adenomas were larger than adenomas at other sites (421+/-983 mg vs 202+/-353 mg, P=.002). Technetium 99 metastable (Tc99m)-sestamibi imaging and IOPTH identified DAs correctly in only 5 of 84 (6%) and 19 of 75 (25%) of patients tested, respectively.
DAs have nonuniform anatomic distribution with predilection for abnormal growth in bilateral superior parathyroids-embryologic remnants of the fourth branchial pouch. Since additional abnormal glands were detected by observation with technetium 99 metastable (Tc99m)-sestamibi imaging and IOPTH rarely aiding detection, unilateral neck exploration may predispose to persistent or recurrent HPT.
Surgery 01/2004; 134(6):995-1003; discussion 1003-4. · 3.10 Impact Factor
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ABSTRACT: A 54-year-old man was diagnosed with a 3.2-cm primary right lower lobe non-small cell lung cancer and a synchronously present 2.5-cm right adrenal gland mass. Workup of the adrenal lesion revealed a pheochromocytoma. The patient underwent combined mediastinoscopy, laparoscopic right adrenalectomy, and right thoracotomy with right lower lobectomy. This case illustrates the importance of establishing a firm diagnosis for all synchronously present adrenal lesions that are discovered in the setting of primary lung carcinoma.
The Annals of Thoracic Surgery 10/2002; 74(3):924-6. · 3.74 Impact Factor
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ABSTRACT: Our goal is to develop effective islet xenografts for treating human diabetes. We have studied microencapsulated neonatal porcine islet cell clusters (ICCs) transplanted intraperitoneally in spontaneously diabetic NOD mice, where they function to maintain normoglycemia in the autoimmune host. Nonencapsulated neonatal porcine ICCs functioned for 4.5 +/- 0.5 days before being rejected; encapsulation prolonged graft function to 17 +/- 2 days. CTLA4-Ig treatment did not enhance the survival of nonencapsulated ICCs. However, CTLA4-Ig treatment significantly extended the function of encapsulated ICCs to 73 +/- 5 days. Histological analyses demonstrated a profuse pericapsular cellular reaction associated with rejection of encapsulated islet xenografts in untreated mice, while this reaction was significantly reduced in CTLA4-Ig-treated mice. To study mechanisms of xenograft rejection in this model, we analyzed proliferative responses to neonatal porcine ICCs and cytokines present in the peritoneal cavities of transplanted mice. Spleen cells from both CTLA4-Ig-treated and untreated rejecting NODs exhibited vigorous proliferation in the absence of antigenic stimulation, suggesting prior activation in vivo, while splenocytes from CTLA4-Ig-treated NODs with functioning grafts had low proliferative levels, equal to controls. Islet-specific proliferation was not detected in islet-rejecting mice, perhaps due to their high background levels. With the exception of elevated IL-6 levels, empty capsules did not provoke a significant peritoneal cytokine response compared with sham surgery or untransplanted control mice. However, IL-5, IL-12, TGF-beta, and IL-1beta were significantly elevated in NODs receiving encapsulated neonatal porcine ICCs compared with untransplanted controls. There were no significant differences between peritoneal cytokine concentrations in CTLA4-Ig-treated mice with long-term functioning grafts compared to mice that rejected grafts at earlier time points. We conclude that the combination of donor islet microencapsulation and brief treatment of the recipient with co-stimulatory blockade delays sensitization of the host, possibly by altering mechanism(s) for recruitment and/or activation of host effector cells.
Cell Transplantation 02/2002; 11(7):695-705. · 5.13 Impact Factor
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ABSTRACT: Nearly 600 cases of laparoscopic adrenalectomy have been described in the world literature, documenting the safety and effectiveness of the procedure. Comparative studies have demonstrated the advantages of the laparoscopic approach when compared to traditional open approaches to adrenalectomy, documenting a more rapid and comfortable recovery, shorter hospitalization, and fewer complications. Several techniques of laparoscopic adrenalectomy have been described. We prefer the transabdominal approach in the lateral decubitus position. Herein we report our experience with 28 adrenalectomies using this approach. Indications for adrenalectomy have been hyperaldosteronism (9), hypercortisolism (4), pheochromocytoma (3), incidentaloma (6), metastasis (3), lymphoma (1), angiomyolipoma (1), other (1). Average tumor size was 3.3 cm (1. 4-8.3 cm). Average operative time was 152 minutes (110-210 minutes), with left adrenalectomy taking slightly longer to perform than on the right (156 vs. 145 minutes). There were no intraoperative complications and one conversion to open adrenalectomy for a large metastatic lung cancer found to be invading the liver. One patient experienced left rib pain from a cannula site immediately at the costal margin. There were no other complications. Average length of hospitalization was 2.3 days (1-6 days). With this and others' experience, laparoscopic adrenalectomy has become the gold standard for adrenalectomy. This manuscript reviews the literature on laparoscopic adrenalectomy and describes the transabdominal lateral approach.
World Journal of Surgery 03/1999; 23(4):389-396. · 2.36 Impact Factor
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ABSTRACT: Our goal is to develop effective islet grafts for treating type 1 diabetes. Since human islets are scarce, we evaluated the efficacy of a microencapsulated insulin-secreting conditionally transformed allogeneic β-cell line (βTC-tet) in non-obese diabetic mice treated with tetracycline to inhibit cell growth. Relatively low serum levels of tetracycline controlled proliferation of βTC-tet cells without inhibiting effective control of hyperglycemia in recipients. There was no significant host cellular reaction to the allografts or host cell adherence to microcapsules, and host cytokine levels were similar to those of sham-operated controls. We conclude that encapsulated allogeneic β-cell lines may be clinically relevant, because they effectively restore euglycemia and do not elicit a strong cellular immune response following transplantation. To our knowledge, this is the first extensive characterization of the kinetics of host cellular and cytokine responses to an encapsulated islet cell line in an animal model of type 1 diabetes.
Biochemical and Biophysical Research Communications.
