A review of in vitro and in vivo culture techniques for the study of pancreatic carcinogenesis.
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Ten cases of large hepatocellular carcinoma (HCC) (largest diameter, 6.5-15 cm) were surgically resected from 3 to 19 days after transcatheter hepatic arterial embolization (TAE) for histologic assessment of the effectiveness. Another two patients, including one with a small HCC (3.5 X 3 X 3 cm) who died of complications, were also studied. The patients' ages ranged from 20 to 64 years, 11 were men and 1 was a woman, and all positive for serum hepatitis B surface antigen. All 11 cases with large HCC were symptomatic before the HCC was clinically diagnosed. Alpha-fetoprotein levels were elevated in ten cases but immediately dropped to normal levels after TAE and resection in eight cases. An effective massive tumor coagulative necrosis of 99% already occurred 3 days after TAE. A necrosis involving more than 95% of the whole tumor mass was demonstrated in eight cases: one was a large HCC taken from an autopsy specimen, and TAE was done three times. This strongly indicates the effectiveness of TAE on the destruction of HCC. However, the presence of viable residual tumors in 11 cases also strongly argues for the necessity for surgical resection whenever it is possible. The failure of a complete necrosis was related to the extracapsular extension, liver invasion, satellite nodules, and portal vein involvement, and probably related to collateral and portal vein blood supply.
Patients with primary and a few with secondary liver tumors were embolized through the hepatic artery. Lipiodol and doxorubicin occluded peripherally, which was immediately followed by central embolization with gelatin sponge cubes. Preoperative embolizations were made for diagnostic and possible surgical adjuvant purposes. Extensive postembolization necrosis was common in tumors less than 5 cm in diameter, and tumor markers usually decreased temporarily after treatment. There were moderate side effects of pain, fever and nausea, and an acceptable complication and mortality rate with no deaths after embolization alone. This warrants further research on the method, which also seemed to improve the detection rate for small hepatocellular carcinomas.
BACKGROUND: Hepatocellular carcinoma (HCC) is a common malignancy worldwide with limited effective therapeutic options available or appropriate for cirrhotic patients. METHODS: Chemoembolization, using sequential intra-arterial doxorubicin/ethiodized oil and gelatin sponge particle/ethanol embolization, was used to treat patients with unresectable HCC localized to the liver. Fifty-two patients were treated in this manner from 1988 to 1992. The objective response was determined by sequential computed tomography (CT) scans. RESULTS: Of the 47 patients evaluable for response, 20 (43%) achieved a partial response, and 12 (26%) achieved a minor response. Sixteen patients underwent repeated chemoembolization for locally recurrent disease as many as three times after the initial procedure. All 52 patients were evaluable for survival and toxicity, with a median follow-up of 14 months. Twelve-month survival was 60%, and median survival was 16 months. This compares favorably with values reported in the literature of approximately 20% and 6-14 weeks, respectively. There was a 17% 30-day mortality, with a slightly higher risk for patients with portal vein obstruction. Other toxicities generally were mild and transient, including fever, pain, encephalopathy, and malaise. CONCLUSIONS: Chemoembolization may enhance survival for patients with unresectable, localized HCC. It appears to be an effective alternative to standard treatment, even in cirrhotic patients.
Adult mesenchymal stem cells (MSCs), found in the bone marrow, have the potential to differentiate into multiple connective tissue types, including cartilage. In this study, we examined the potential of a porous gelatin sponge, Gelfoam, for use as a delivery vehicle for MSCs in cartilage regeneration therapy. Adult human MSCs (hMSCs) were seeded throughout the gelatin sponge after a 2-h incubation period. When cultured for 21 days in vitro in a defined medium supplemented with 10 ng/mL of TGF-beta 3, hMSC/Gelfoam constructs produced a cartilage-like extracellular matrix containing sulfated glycosaminoglycans (s-GAGs) and type-II collagen, as evident upon histologic evaluation. Constructs loaded with a cell suspension of 12 x 10(6) cells/mL produced an extracellular matrix containing 21 microg of s-GAG/microg of DNA after 21 days of culture. This production was more efficient than constructs loaded at higher or lower cell densities, indicating that the initial seeding density influences the ability of cells to produce extracellular matrix. When implanted in an osteochondral defect in the rabbit femoral condyle, Gelfoam cylinders were observed to be very biocompatible, with no evidence of immune response or lymphocytic infiltration at the site. Based on these observations we conclude that Gelfoam resorbable gelatin sponge is a promising candidate as a carrier matrix for MSC-based cartilage regeneration therapies.
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The internal mammary artery (IMA) is increasingly used as a coronary bypass conduit because of better long-term patency and improved prognosis as compared with venous grafts. Previous investigators have suggested that the "steal" of blood flow of the IMA graft via the subclavian artery or a persistent large side branch of the graft may lead to its thinning. However, only a few reports have described the embolization of a large side branch using a transcatheter procedure. We present a case of repeated embolization of a large lateral costal side branch of the left internal mammary arterial graft applying gelatin sponge particles and micro coils, as well as angioplasty to the graft conduit, with resulting easing of chest pain.
BACKGROUND: Giant cell tumors of the bone can behave as aggressive and sometimes lethal tumors. In the sacrum, the tumor can be extremely difficult to manage. Standard treatments, including surgery and radiation, are associated with significant complications and recurrence rates. The goal of this study is to evaluate the long-term outcome of selective arterial embolization as an alternative treatment modality. METHODS: From 1975 to 2001, 18 patients were treated with selective intraarterial embolization. The embolization method was a combination of Gelfoam particles and coils for peripheral and central occlusions, respectively. The number of embolizations was based on clinical symptoms, radiographic response, and the vascularity of the tumor. Nine patients received intraarterial cisplatin as part of their treatment. The median follow-up was 105 months. RESULTS: Of 18 patients, 14 responded favorably to embolization with improvement in pain and neurologic symptoms. Computed tomographic and magnetic resonance imaging scans showed reossification and stabilization of tumor size. Arteriograms showed diminished vascularity. With long-term follow-up, three patients developed late disease recurrences within the sacrum. Kaplan-Meier analysis showed that the risk of local recurrence is 31% at 10 years and 43% at 15 and 20 years. The long-term outcome was not affected by intraarterial cisplatin. There was one death that occurred 1 day after embolization. CONCLUSIONS: Most patients demonstrate an objective early radiographic response to embolization. Long-term follow-up shows that the response is durable in approximately one half of the patients. Given the potential morbidity of other treatments, embolization should be included in the armamentarium of treatment for this difficult disease. Embolization may be used alone or in conjunction with other therapy. Long-term follow-up is recommended for all patients because late disease recurrence or sarcomatous change can occur.
We have examined the migratory capacity of Schwann cells from the distal stump of a 1-week transected sciatic nerve of adult rat for a distance of 10 mm. The distal stump was introduced into the open end of a silicone chamber packed with artificial fibrin sponge (Gelaspon) soaked in phosphate-buffered saline (control chambers), cytosine arabinoside (Ara-C) (0.05 mM), or insulin (40 U/ml). Migrating Schwann cells were distinguished from fibroblasts by the presence of non-specific cholinesterase (nChE) activity and glial fibrillary acidic protein (GFAP). The cells of distal stumps including Schwann cells accepted Gelaspon as a suitable adhesive substratum. In the chambers filled with Gelaspon soaked in phosphate-buffered saline alone Schwann cells were outnumbered by fibroblasts. The addition of Ara-C resulted in greater numbers of Schwann cells, which migrate longer distances into the chambers. The application of insulin enhanced Schwann cell migration as well. These morphologic observations were further supported by biochemical measurements of nChE activity. The results suggest an influence on Schwann cell migration by fibroblasts of connective tissue sheaths and a stimulation of Schwann cell migration by insulin.
Toxic shock syndrome (TSS) is a serious multisystem disease that was first described in 1978 by Todd. It occurs most often in menstruating women using superabsorbent tampons. The exact pathogenesis is not well understood, but it is felt to be due to the effects of an enterotoxin produced by certain strains of Staphylococcus aureus. The reported incidence of TSS following nasal surgery is 16/100,000. We report a case of TSS following endonasal sinus surgery in which minimal packing was used. The nasal surgeon should be aware of this rare and possibly fatal entity, as TSS may occur following any nasal/sinus surgery, even where packing is minimal and of short duration and when the patient is receiving antibiotic therapy.
A patient with severe bleeding due to carcinoma of the pharynx, uncontrollable by surgical intervention, was successfully treated by bilateral transcatheter embolization of the external carotid arteries using gel-foam. Although these lesions may appear hypovascular angiographically, this does not preclude embolization as a valuable therapeutic technique. Our experience with this patient indicates that transcatheter embolization is an especially appropriate approach to controlling bleeding in patients with extensive malignant disease when no other therapy is available.
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Preoperative portal vein embolization (PVE) was performed in 84 patients before extensive liver resection for various diseases. By the criteria of liver volumetric determination, some patients were candidates for PVE, whereas others were not, even though the same surgical procedure, such as extended right lobectomy (ERL), was scheduled. PVE using gelatin sponge powder induced hypertrophy in the nonembolized lobe (0%-171%; median, 30%) and proportional atrophy in the embolized lobe in 2 weeks without eliciting any major inflammatory or necrotic reaction, as evidenced histologically and by the minimal elevations in the serum aspartate transaminase (AST) and alanine transaminase (ALT) values. Alterations in the total bilirubin level and prothrombin time were also insignificant and transient, indicating that hepatocyte functions were not impaired by PVE. Not all patients who undergo PVE proceed with the scheduled hepatic resection procedure, so it is a great advantage that gelatin sponge causes minimal damage compared with other embolizing materials such as cyanoacrylate and absolute ethanol, which have been reported to induce an inflammatory reaction or histological alteration. Our multiple regression analysis showed that three factors, diabetes mellitus, a high total bilirubin level at the time of PVE, and being male, each reduced the extent of hypertrophy in the nonembolized lobe (r2 =.30). By contrast, cholestasis appeared to accelerate the process of atrophy in the embolized lobe (r2 =.16). In conclusion, PVE by gelatin sponge powder is a safe and effective preoperative maneuver that induces hypertrophy of the section of the liver that will remain after partial hepatectomy.
The purpose of our study was to evaluate the outcome, patterns of failure, and toxicity for patients with unresectable hepatocellular carcinoma (HCC) treated with radiotherapy, transcatheter arterial chemoembolization (TACE), or combined TACE and radiotherapy. Forty-two patients with unresectable HCC were treated with combined radiotherapy and TACE (TACE+RT group, 17 patients), radiotherapy alone (RT group, 9 patients), or with TACE alone (TACE group, 16 patients). Mean dose of radiation was 46.9 +/- 5.8 Gy in a daily fraction of 1.8 to 2 Gy, directed only to the cancer-involved areas of the liver. TACE was performed with a combination of Lipiodol, doxorubicin, cisplatin, and mitomycin C, followed by Gelfoam or Ivalon embolization. Tumor size was smaller in the TACE group (mean: 5.4 cm) compared with the TACE+RT group (8.6 cm) and the RT group (13.1 cm) (P = 0.0003). The median follow-up was 24 months in the TACE+RT group, 28 months in the RT group, and 23 months in the TACE group. Survival was significantly worse for patients treated with radiotherapy alone due to the selection bias of patients with more advanced disease and compromised condition in this group. In contrast, the TACE+RT and TACE groups had comparable survival (two-year rates: TACE+RT 58%, TACE 56%, P = 0.69). The local control rate for the treated tumors was similar in the TACE+RT and TACE groups (P = 0.11). The intrahepatic recurrence outside the treated tumors was common and similar between these two groups (P = 0.48). The extrahepatic progression-free survival was significantly shorter for patients in the TACE+RT group than in the TACE group (two-year rates: TACE+RT 36%, TACE 100%, P = 0.002). Seven patients died from complications of treatment. Local radiotherapy may be added to treat patients with unresectable HCC, and the control of progression of the treated tumors was promising even in patients with large hepatic tumors. Survival of patients with combined TACE and radiotherapy was similar to that with TACE as the only treatment, while a significant portion of the patients treated with radiotherapy developed extrahepatic metastasis.
We previously demonstrated increased numbers of CD34(+) progenitor cells in the peripheral blood of tumor bearers. Also demonstrated was the feasibility of chemoattracting these cells by sponge implants containing VEGF. The present study used a murine Lewis lung carcinoma (LLC) model to test if CD34(+) cells that are chemoattracted to a tumor excision site can be differentiated in situ into dendritic cells and whether this leads to increased local immune reactivity. After surgically excising established LLC tumors, mice received at the excision site gelatin sponge implants containing VEGF to chemoattract CD34(+) cells, and/or GM-CSF plus SCF to induce CD34(+) cell differentiation into dendritic cells. In some studies, lysates of GFP-transfected LLC cells (LLC(GFP)) were also included in the implants as a source of tumor antigen. After 2 weeks, implants and local lymph nodes were removed and analyzed. Implants containing VEGF, GM-CSF/SCF or VEGF/GM-CSF/SCF had a higher proportion of CD34(+) cells compared to control implants. However, the number of dendritic cells was higher in implants containing GM-CSF/SCF or VEGF/GM-CSF/SCF than those containing either VEGF or diluent. Regional lymph node from mice containing GM-CSF/SCF or VEGF/GM-CSF/SCF implants showed increased dendritic cell levels. However, when lysates from LLC(GFP) were added to the implants, the highest proportion of dendritic cells associated with GFP was in lymph nodes of mice containing GM-CSF/SCF implants. Lymph node cells from mice with GM-CSF/SCF or VEGF/GM-CSF/SCF had a higher level of proliferation and IFN-gamma secretion in response to in vitro LLC lysate challenge, with the greatest response being from lymph node cells of mice with GM-CSF/SCF implants. These results suggest the feasibility of using GM-CSF/SCF-containing implants to increase dendritic cell levels, uptake of tumor antigens, trafficking to lymph nodes and stimulation of immune reactivity at tumor excision sites with residual tumor.
This study proposes a new three-dimensional culture of mouse hepatocytes in a porous galactose-carrying modified gelatin sponge matrix. The modification of gelatin using galactose residues significantly increased the attachment of hepatocytes on the substrate. A modified gelatin sponge with lactobionic acid (MGLA) was prepared to increase the specific interaction between the hepatocytes and the matrix. Hepatocytes cultured in a three-dimensional MGLA sponge released much less lactate dehydrogenase than those cultured on a collagen Type I-coated monolayer. Moreover, the survival rate of hepatocytes cultured on an MGLA sponge was longer than the survival rate of hepatocytes cultured on a collagen Type I-coated monolayer. Hepatic specific metabolic functions, namely, the secretion of serum albumin and the synthesis of urea, were well maintained and promoted by spheroidal hepatocytes formed in the MGLA sponge.
Leukocyte infiltration into infected tissues is essential for the clearance of microorganisms. In animals with a cell-mediated immune (CMI) response to the infectious agent, as opposed to naive animals, leukocyte migration is greatly enhanced into sites of the organism or antigen. The role of the,chemotactic cytokine or chemokine, macrophage inflammatory protein-1 alpha (MIP-1 alpha), in the expression phase of the CMI response and in protection against Cryptococcus neoformans was assessed. With the use of a gelatin sponge model in mice as a means of detecting an anti-cryptococcal delayed-type hypersensitivity (DTH) reaction, we found that MIP-1 alpha levels in fluids from cryptococcal antigen (CneF)-injected sponges in immunized mice (DTH-reactive sponges) were significantly increased over levels of MIP-1 alpha in fluids from saline-injected control sponges at 12 and 24-30 h after injection. MIP-1 alpha levels peaked before increases in neutrophils and lymphocytes in the DTH-reactive sponges, suggesting that MIP-1 alpha was responsible, at least in part, for attracting these leukocyte types. Immunized mice treated with neutralizing antibody to MIP-1 alpha before sponge injection with CneF had reduced numbers of neutrophils and lymphocytes in the DTH-reactive sponges and showed reduced clearance of C. neoformans from the lungs, spleens, livers, and brains when compared with controls. Furthermore, injection of rmMIP-1 alpha into sponges in naive mice resulted in an increase in the influx of neutrophils and lymphocytes into the sponges compared with saline-injected sponges. Together our findings provide solid evidence that MIP-1 alpha is a component of the anticryptococcal DTH reaction. In addition, MIP-1 alpha influences neutrophil influx and attracts lymphocytes into the DTH reaction site. Finally, we showed that MIP-1 alpha plays a role in protection against C. neoformans.