Optimization of 3D autologous chondrocyte-seeded polyglycolic acid scaffolds to mimic human ear cartilage

Auricular reconstruction in children with microtia is one of the more complex procedures in plastic surgery. Obtaining sufficient native material to build an ear requires harvesting large fragments of rib cartilage in children. Herein, we investigated how to optimize autologous chondrocyte isolation, expansion and re-implantation using polyglycolic acid (PGA) scaffolds for generating enough cartilage to recapitulate a whole ear starting from a small ear biopsy. Ear chondrocytes isolated from human microtia subjects grew slower than microtia rib or healthy ear chondrocytes and displayed a phenotypic shift due to the passage number. Rabbit ear chondrocytes co-cultured with mesenchymal stem cells (MSC) at a 50 : 50 ratio recapitulated the cartilage biological properties in vitro. However, PGA scaffolds with different proportions of rabbit chondrocytes and MSC did not grow substantially in two months when subcutaneously implanted in immunosuppressed mice. In contrast, rabbit chondrocyte-seeded PGA scaffolds implanted in immunocompetent rabbits formed a cartilage 10 times larger than the original PGA scaffold. This cartilage mimicked the biofunctional and mechanical properties of an ear cartilage. These results indicate that autologous chondrocyte-seeded PGA scaffolds fabricated following our optimized procedure have immense potential as a solution for obtaining enough cartilage for auricular reconstruction and opens new avenues to redefine autologous cartilage replacement.

Benefits of collaborative learning for environmental management: applying the integrated systems for knowledge management approach to support animal pest control

Resource management issues continually change over time in response to coevolving social, economic, and ecological systems. Under these conditions adaptive management, or "learning by doing," offers an opportunity for more proactive and collaborative approaches to resolving environmental problems. In turn, this will require the implementation of learning-based extension approaches alongside more traditional linear technology transfer approaches within the area of environmental extension. In this paper the Integrated Systems for Knowledge Management (ISKM) approach is presented to illustrate how such learning-based approaches can be used to help communities develop, apply, and refine technical information within a larger context of shared understanding. To outline how this works in practice, we use a case study involving pest management. Particular attention is paid to the issues that emerge as a result of multiple stakeholder involvement within environmental problem situations. Finally, the potential role of the Internet in supporting and disseminating the experience gained through ongoing adaptive management processes is examined.

Porphyria cutanea tarda and hepatitis C and B viruses infection: a retrospective study

Based on the knowledge that patients with porphyria cutanea tarda (PCT) usually have chronic liver disease, several authors studied a possible relationship to hepatotropic virus infections. However, the prevalence of hepatitis B virus (HBV)-DNA by polymerase chain reaction (PCR) in serum of these patients, as well as the presence of hepatitis C virus (HCV)-RNA in paired liver, peripheral blood mononuclear cells (PBMCs), and serum samples in these patients has not been reported. We have studied 34 patients with sporadic PCT. Antibodies against HBV were detected in 91% of the patients, but in only 41% of the patients against HBV (P < .01). Viral genomes of HCV and HBV were detected in 65% and 40% of our patients, respectively (P < .05). Genomic and antigenomic HCV strands were found in liver biopsy specimens (100% and 54%), mononuclear cells (100% and 54%), and serum (45% and 0%) from 11 patients. Twelve patients were retrospectively studied, and no correlation was observed between the appearance or disappearance of viral genomes and the simultaneous presence of both genomes with the course of porphyria. In our patients with PCT, detection of viral genomes did not correlate with phlebotomy or length of time since PCT was diagnosed. Our findings demonstrate that HCV infection may be underestimated when detection is performed only in serum of PCT patients, and that HBV infection might also be increased in PCT.

Esophageal inflammatory fibroid polyp. Endoscopic and radiologic features

We present the case of a 60-year-old male patient, who had several episodes of melena during the last years. One month ago he had a new episode of digestive bleeding, and an endoscopic study was performed that showed at 35 cm from the dental arcade a polypoid, pedunculated lesion, with a diameter of 5 cm and a submucosal aspect, a few erosions on its surface and a fibrin deposit. Its head reached the cardia, and it bled when touched by the endoscope. The biopsies taken were negative. X-ray and CT studies confirmed the existence of a mass compatible with a submucosal lesion. The patient was operated and the tumor was excised. The histologic study showed an inflammatory fibroid polyp, an entity very rarely described at the level of the stomach, duodenum, small intestine, and colon and exceptionally described at the esophageal level.

Changes in cytokine production during therapy with granulocyte-macrophage colony-stimulating factor in patients with chronic hepatitis B

Recombinant human granulocyte-macrophage colony-stimulating factor therapy significantly reduces serum hepatitis B virus DNA levels, associated with increased 2',5'-oligoadenylate synthetase activity in cultured mononuclear cells of patients with chronic hepatitis B. To assess changes in immune function during therapy of chronic hepatitis B patients, spontaneous and mitogen-induced production of tumor necrosis factor-alpha, interleukin-1 beta, interleukin-6, interferon-alpha and interferon-gamma were measured-along with serum levels of soluble CD4, soluble CD8, soluble interleukin-2 receptor and beta 2-microglobulin-before, during and after a 6-wk course of granulocyte-macrophage colony-stimulating factor in nine patients with chronic hepatitis B. Treatment statistically enhanced spontaneous production of tumor necrosis factor-alpha (p < 0.05) and interleukin-1 beta (p < 0.02). Furthermore, spontaneous interleukin-6 production correlated negatively with hepatitis B virus DNA levels (p < 0.03), and spontaneous interleukin-1 beta production correlated positively with 2',5'-oligoadenylate synthetase activity (p < 0.0005). In addition, statistically significant increases were found during therapy in serum levels of soluble interleukin-2 receptor (p < 0.01), soluble CD4 (p < 0.01) and beta 2-microglobulin (p < 0.05). Levels of soluble interleukin-2 receptor and soluble CD4 correlated negatively with levels of hepatitis B virus DNA (p < 0.05), and levels of soluble interleukin-2 receptor and beta 2-microglobulin correlated positively with 2',5'-oligoadenylate synthetase activity (p < 0.003 and p < 0.02, respectively). Thus recombinant human granulocyte-macrophage colony-stimulating factor administration may induce reductions in hepatitis B virus DNA levels, perhaps by altering the immune status and increasing cytokine production.

Treatment of chronic hepatitis B with recombinant interferon alpha versus recombinant interferon alpha plus levamisole

To compare the efficacy and tolerance of the simultaneous administration of levamisole plus IFN versus treatment with IFN alone in chronic hepatitis B, 39 patients were randomly assigned into two groups. Nineteen patients received 15 million units of recombinant alpha interferon 2b (rIFN-alpha 2b) 3 times a week for 4 months. The other 20 patients were treated with the same dose and schedule of rIFN-alpha 2b and 150 mg of levamisole simultaneously given during the first 6 weeks of treatment. At the end of the study (thirteenth month), serum HBV-DNA was negative in 59% of patients treated with interferon alone and in 37% of those treated with interferon and levamisole. HBeAg was negative in a similar percentage in the two groups (41% vs. 37%). Serum alanine aminotransferase levels decreased in patients who lost viral DNA. These data demonstrate that the combination of alpha interferon and levamisole, at the doses and under the schedule used in this study, does not achieve better results than the treatment with alpha interferon alone. Although tolerance to the simultaneous administration of alpha interferon and levamisole is good, secondary effects may be hazardous.

Pilot study of recombinant human granulocyte-macrophage colony-stimulating factor in the treatment of chronic hepatitis B

Recombinant human granulocyte-macrophage colony-stimulating factor is being used to improve the immunological function of patients with various diseases and to ameliorate hematological disorders. We investigated the tolerance and possible antiviral effect of the administration of daily doses of recombinant human granulocyte-macrophage colony-stimulating factor (3, 1 or 0.5 micrograms/kg body wt) to nine patients with chronic hepatitis B, alone or in combination with 5 MU interferon-alpha 2b. Recombinant human GM-CSF reduced significantly (p < 0.02) hepatitis B virus DNA levels. The three doses used were equally effective. Of the eight patients who completed the study, four became negative for HBV DNA and HBeAg; two of them seroconverted to HBe antibody. These four patients showed improvement in the histological activity of their liver disease. Ultimately, two patients regained normal ALT values. 2',5'-Oligoadenylate synthetase activity increased significantly (p < 0.01) in cell lysates of mononuclear cells cultured in vitro, coinciding with the reductions in hepatitis B virus DNA levels. Recombinant human granulocyte-macrophage colony-stimulating factor was well tolerated but produced a dose-dependent increase in white blood cell counts. It became intolerable at doses of 3 micrograms (and was reduced to 1.5 microgram); this effect was reversible after cessation of recombinant human granulocyte-macrophage colony-stimulating factor treatment. No remarkable variations occurred in other parameters. In conclusion, recombinant human granulocyte-macrophage colony-stimulating factor administration is safe and tolerable at doses of 0.5 to 1 microgram/kg body wt and may exert an antiviral effect in chronic hepatitis B.(ABSTRACT TRUNCATED AT 250 WORDS)

[Cancer of the middle third of the choledochus: an infrequent diagnosis]

We report the case of an 80-year-old woman with a previous history of HBP, hysterectomy due to cancer of the uterus and cholelithiasis, who was admitted in our hospital because of diffuse abdominal pain, marked jaundice, choluria and acholia during one week, together with anorexia and loss of weight. Blood chemistry results disclosed a total bilirubin of 11 mg/dl, a direct bilirubin of 8 mg/dl, GGTP 826 U/I, alkaline phosphatase 287 U/I, AST 285 U/I, ALT 837 U/I and LDH 242 U/I. The CA 19-9 marker was higher than 500 U/ml. The abdominal ultrasound examination did not show any space-occupying lesions; the extra and intrahepatic bile ducts were very dilated and the gall bladder showed multiple stones within its contents. The endoscopic retrograde cholangiopancreatography (ERCP) showed a homogeneous filiform defect at the middle third of the common bile duct of approximately 1 cm in length and with a marked dilatation of the bile ducts. A percutaneous drainage of the bile tree was performed, but the patient died.

An escalating dose regime of recombinant interferon-alpha 2A in the treatment of chronic hepatitis C

Interferon-alpha (IFN-alpha) has proven useful in the treatment of chronic hepatitis C, but a relapse in response is frequently observed. The possible benefit of daily administration of recombinant IFN-alpha 2A at an escalating (from 1.5 to 9 MU) regime depending on the evolution of serum aminotransferase (ALT) levels was evaluated in 31 adult patients with chronic hepatitis C. At the end of the first month with 1.5 MU of rIFN-alpha 2A, 9/31 (29%) had normal ALT values. Then, 22 patients were given 3 MU daily and at the second month 4 patients (18%) normalized ALT values. The 18 non-responders received 6 MU and 4 of them (22%) normalized ALT values (1 patient dropped out). Finally, the remaining 13 non-responders were given 9 MU and in 4 (30%) ALT fell to normal ranges. Three non-responders to 1.5 MU normalized ALT values when the dose of rIFN-alpha 2A was increased (n = 2, 3 MU; n = 1, 9 MU). The overall response achieved was 68%. Within 3 months after cessation of treatment, 12/20 (60%) responder patients had a relapse in ALT levels. Therefore, although daily administration of rIFN-alpha 2A does not improve the results obtained with a thrice-weekly schedule, a proportion of non-responders could benefit from an escalating dose to a high amount (63 MU/week) of rIFN-alpha 2A.

Immunoglobulin M antibody to hepatitis C virus during interferon therapy for chronic hepatitis C

Testing for immunoglobulin (Ig) M antibody to hepatitis C virus (anti-HCV) as a predictive factor of therapeutic response to recombinant interferon alfa (rIFN-alpha) in chronic hepatitis C was evaluated in 122 patients with IgG anti-HCV. IgM anti-HCV was present in the pretreatment sample of 88% of patients who responded to treatment, including 20 of 21 (95%) long-term responders and 24 of 29 (83%) responders who had relapses after cessation of therapy. In contrast, IgM anti-HCV was present in only 23 of 39 (59%) nonresponders and 22 of 33 (66%) untreated controls (P less than 0.05). The number of cases with detectable IgM anti-HCV tended to decrease in responder patients, which was more evident for complete responders (42%) than for responders who relapsed (72%). During follow-up, the antibody became undetectable in the majority of long-term responders (28% were still IgM anti-HCV positive) but remained detectable in 69% of responders who relapsed (P less than 0.05). No special changes were noted in nonresponder or control patients. Thus, testing for IgM anti-HCV may help to identify a subset of patients who will benefit from rIFN-alpha therapy in chronic hepatitis C.