Der Einfluß von Metaboliten auf die Proliferation von Novikoff-Hepatoma Tumorzellen : eine in vivo Untersuchung an CD Ratten

Während der Tumorentstehung kommt es durch die Dimerisierung der Pyruvatkinase zu einem relativen Stop der Glykolyse. Gleichzeitig wird in diesen Zellen die Glutaminolyserate erhöht. Die Zielsetzung der vorliegenden Dissertation war es, in diesem Zusammenhang zu untersuchen, ob durch die kontinuierliche Perfusion mit Fructose-1,6-P2 (FBP), Aminooxyessigsäure, Cisplatin, Glycerat-3-P bzw. Bernsteinsäure-monomethylester den Tumorstoffwechsel beeinflusst und das maligne Wachstum gehemmt wird. Bekanntlich hemmt Aminooxyessigsäure direkt die Glutamat-Oxalacetat-Transaminase, Bernsteinsäure-mono-methylester, ein synthetisches Analogon von Glutamin, interferiert mit der Glutaminolyse. Glycerat-3-P wird durch proliferierende Zellen in Serin umgewandelt. Serin und FBP haben ihrerseits die Fähigkeit die M2-PK aus der inaktiven dimeren Form in die aktive tertramere Struktur umzuwandeln. Cisplatin wurde als eine Vergleichssubstanz eingesetzt. Die Kontrollgruppe wurde mit NaCl perfundiert. Als Tumor-Zellmodell dienten mit Novikoff Hepatoma (NH) Zellen injizierte CD Ratten. Die Zellen wurden in zufällig gewählten Tieren intraperitoneal passagiert, und es wurden anschliessend jeweils 1x106 NH-Zellen pro Ratte in den rechten Glutaeus maximus injiziert. Vorversuchen hatten gezeigt, dass in Zellkultur passagierte Zellen ihre Malignität verloren hatten. Nach dem Auftreten von Tumoren wurden die Tiere randomisiert und für durchschnittlich 9-10 Tage über einen Jugularis-Katheter kontinuierlich mit den jeweiligen Substanzen perfundiert. Hierbei wurde täglich die Tumorgrösse mittels einer Schublehre gemessen und hieraus ihr Volumen (cm3) berechnet. Am Ende der Versuche wurde der Tumor herauspräpariert und mittels Wasserverdrängung ihr Volumen (ml) bestimmt und die Anzahl der Metastasen und ihr Volumen bestimmt. Zusätzlich wurde in einem weiteren Versuch aus den Blutproben der Tiere ermittelt, ob die verwendeten Substanzen eine immunmodulatorische Wirkung auf die natürlichen Killerzellen zeigten und ihre Aktivität beeinflussten. Hierfür wurde der Zyto Tox 96® Test verwendet. Die Tiere, welche mit FBP behandelt wurden, zeigten im Verlauf ein geringeres Wachstum der Tumoren, ein geringeres Tumorendvolumen und es kam zu einer signifikant geringeren Metastasenbildung gegenüber den Kontrolltieren, die mit NaCl perfundiert worden waren. Somit scheint FBP von allen übrigen hier untersuchten Substanzen am potentesten den Tumorstoffwechsel zu beeinflussen. Für Aminooxyessigsäure, Bernsteinsäuremonomethylsäure und Glycerat-3-P konnte gezeigt werden, dass die Tumorendvolumina (ml) am Ende des Versuchs signifikant kleiner waren. Auch der geringere Nachweis von makroskopischen Metastasen zeigt, dass sie den Stoffwechsel der Novikoff Hepatoma beeinflussen. Für Cisplatin zeigte unter der angewandten Dosierung (5 µg) keine Wirkung auf das Tumorwachstum. Für FBP und Aminooxyessigsäure konnte zudem eine immunmodulatorische Wirkung auf die Natürlichen-Killerzellen (NK) nachgewiesen werden. Die NK zeigten im Zyto Tox 96® Test eine deutlich höhere Lyserate der Novikoff Zellen.During tumorigenesis dimerization of pyruvate kinase can lead to a termination of gly-colysis. This phenomenon is paralleled by a rise in cellular glutaminolysis. In this con-text, the aim of the presented study was to investigate whether a continuous perfusion with fructose 1,6-P2 (FBP), aminooxyacetic acid, cisplatin, glycerat-3-P or \u27Bernstein-säure-monomethylester\u27 (BME) could alter tumor metabolism and inhibit malignant growth. It is known that aminooxyacetic acid has a direct inhibitory effect on glutamate-oxalacetate-transaminase(GOT). BME, a synthetic analogue to glutamine can interfere with glutaminolysis. Proliferating cells metabolize glycerat-3-P to serine. Serine and FBP in turn have the capacity to convert M2-PK from its inactive dimeric conformation to the active tetrameric form. CD rats, inoculated with Novikoff Hepatoma (NH) cells served as tumor model. Cisplatin was used as a reference substance and saline as control. After intraperitoneal passage in randomized animals, a total of 1x106 NH cells having undergone prior peritoneal passage were injected into the right major gluteus muscle. In pretrials we had established that the cell culture passage of NH cells voided them the ability for malignant growth. After suc-cessful tumor inoculation, animals were randomly distributed to treatment groups re-ceiving either a continuous perfusion of the respective trial substance via jugular cathe-terization for an average of 9-10 days or saline. During this time daily tumor measure-ments with a caliper were performed to calculate tumor volume. At the study endpoint, tumors were dissected, tumor volume was calculated measuring water displacement and the total number of visible metastasis was documented. Additionally, blood samples were taken to investigate possible immunomodulatory effects of the treatment substances on the activity of natural killer (NK) cells using the Zyto Tox 96® kit. During the course of the continuous perfusion, animals receiving FBP showed a marked reduction of tumor growth and tumor volume at the study end point. Furthermore, a sig-nificant reduction of metastasis was seen in the FBP group compared to control animals receiving saline. Of the investigated substances, FBP was most potent in altering tumor metabolism. Additionally, it could be shown that aminooxyacetic acid, BME and glycerat-3-P were all able to significantly reduce tumor volumes. These findings were paralleled by a reduction in total metastasis, confirming the hypothesis that the investi-gated substances were able to influence the Novikoff cell metabolism. Interestingly, cis-platin the standard reference substance, showed no effect on tumor growth in the applied dose (5µg). Both FBP and amino acetic acid had immunostimula-tory effect on NK cells, augmenting the rate of Navikoff cell lysis mediated through NK cells in the Zyto Tox 96® test

Unrecognized hand ischemia after intraarterial drug injection: successful management of a "near miss" event

<p>Abstract</p> <p>Background</p> <p>Complications arising from accidental intraarterial drug injections have been described in the past. However, given the multitude of injected substances and complex pathophysiology, guidelines regarding diagnosis and management of patients with intraarterial injections remain vague. As such it remains unclear, when to expect limb ischemia and whether and for how long to monitor patients after intraarterial injections.</p> <p>Case report</p> <p>We present the case of a "near miss event" in an i.v. drug abuser presenting to the emergency department 3 hours after injection of water dissolved zolpidem (Ambien™) tablets into the right ulnar artery. Chief complaint was forearm pain. Clinical examination at the time revealed no concern for limb ischemia and patient was discharged. The patient returned unplanned 18 hours after injection with an ischemic right hand. Angiography revealed no flow in the distal ulnar artery and minimal flow in the palmar arch. Emergent intraarterial thrombolysis with Urokinase was performed and restored hand perfusion. Clinical follow-up 3 months after injury showed full recovery with regular recapillarisation and normal Allen test.</p> <p>Conclusion</p> <p>This case report highlights the need to rigorously monitor patients with suspected intraarterial injections for potential delayed onset of limb ischemia. This is to our knowledge the first described case report of a successful revascularization after prolonged ischemia with delayed onset after zolpidem injection. We recommend close monitoring of these patients for at least 24 hours in addition to starting prophylactic anticoagulation.</p

Postoperative hypoesthesia and pain: qualitative assessment after open and laparoscopic inguinal hernia repair

Background: Chronic pain is an important outcome variable after inguinal hernia repair that is generally not assessed by objective methods. The aim of this study was to objectively investigate chronic pain and hypoesthesia after inguinal hernia repair using three types of operation: open suture, open mesh, and laparoscopic. Methods: A total of 96 patients were included in the study with a median follow-up of 4.7 years. Open suture repair was performed in 40 patients (group A), open mesh repair in 20 patients (group B), and laparoscopic repair in 36 patients (group C). Hypoesthesia and pain were assessed using von Frey monofilaments. Quality of life was investigated with Short Form 36. Results: Pain occurring at least once a week was found in 7 (17.5%) patients of group A, in 5 (25%) patients of group B, and in 6 (16.6%) patients of group C. Area and intensity of hyposensibility were increased significantly after open nonmesh and mesh repair compared to those after laparoscopy (p = 0.01). Hyposensibility in patients who had laparoscopic hernia repair was significantly associated with postoperative pain (p = 0.03). Type of postoperative pain was somatic in 19 (61%), neuropathic in 9 (29%), and visceral in 3 (10%) patients without significant differences between the three groups. Conclusions: The incidence of hypoesthesia in patients who had laparoscopic hernia repair is significantly lower than in those who had open hernia repair. Hypoesthesia after laparoscopic but not after open repair is significantly associated with postoperative pain. Von Frey monofilaments are important tools for the assessment of inguinal hypoesthesia and pain in patients who had inguinal hernia repair allowing quantitative and qualitative comparison between various surgical technique

Objective hypoesthesia and pain after transabdominal preperitoneal hernioplasty: a prospective, randomized study comparing tissue adhesive versus spiral tacks

Background: Irritation of inguinal nerves with laparoscopic hernia repair may cause chronic neuralgia and hypoesthesia. Hypoesthesia in particular is generally not assessed objectively. We objectively investigated hypoesthesia and chronic pain after transabdominal preperitoneal inguinal hernia repair (TAPP) with titanium spiral tacks (STs) compared with tissue adhesive (TA) for mesh fixation. Methods: Mesh fixation in 80 TAPP procedures was randomized to fixation with ST (n=40) or TA (n=40). The outcome parameters included hypoesthesia assessed with von Frey monofilaments, early postoperative and chronic pain with the visual analog scale (VAS), morbidity (surgical-site infection, hematoma/seroma, relapse of hernia, trocar hernia), and recovery time to normal activity. Results: Median (range) follow-up was 38 (13-56) months. Demographic and baseline parameters were similar in the two groups. Prevalence of hypoesthesia was significantly higher at all postoperative times in the ST group (6weeks: 32 vs. 6%; 6months: 38 vs. 14%; 12months: 34 vs. 13%; 13-56months: 32 vs. 4%). Mean hypoesthesia scores over all time points were significantly higher in the ST group. The percentages of regions with hypoesthesia (abdominal, inguinal, or genitofemoral) following all procedures were higher in the ST group after 6weeks (14 vs. 2%), 6months (15 vs. 5%), and 13-56months (22 vs. 4%). The intensity of pain decreased significantly in both groups over time. Conclusions: Postoperative hypoesthesia depends on the method of mesh fixation during TAPP and is significantly reduced with TA compared with staplin

Organization of Hannover Skin Bank: Sterile culture and procurement protocols for viable cryopreserved allogeneic skin grafts of living donors.

Preserved allogeneic donor skin still represents one of the gold standard therapies in temporary wound coverage in severely burned patients or chronic wounds. Allogeneic skin grafts are currently commercially available as cryo- or glycerol-preserved allografts through skin tissue banks all over the world. Most of the skin tissue banks rely on human cadaveric skin donations. Due to the chronic shortage of human allogeneic transplants, such as skin, and increasing costs in the procurement of allografts from other skin tissue banks, Hannover Medical School has been building up its own skin tissue bank based on allogeneic skin grafts from living donors who underwent surgical treatment (i.e., body-contouring procedures, such as abdominioplasties). This article presents procedures and protocols for the procurement and processing of allogeneic skin grafts according to national legislation and European regulations and guidelines. Beside protocols, initial microbiological data regarding the sterility of the harvested grafts are presented. The results currently form the basis for further investigations as well as clinical applications. In summary, a microbiological testing and acceptance procedure is presented that ensures adequate patient safety and skin viability

Free flaps in scar treatment

Scar management needs defined concepts and an algorithm to restore functional and aesthetic units. After an unsuccessful conservative treatment, surgical measures provide a vast spectrum of possibilities for remediation. The spectrum of possibilities consists of excision and Z-plasty, regional flaps, vascularized pedicled flaps, tissue expansion, and finally free tissue transfer. Severe scarring and highly destructed tissues with inferior functional and aesthetic units can be effectively treated with radical excision and free flap reconstruction. The complexity of flap architecture and tissue qualities allows for an individualized approach. Specific attention should be paid to the long-term consequences of severe scarring with progressive loss of functionality

Complex facial reconstruction with invasive and non-invasive conventional interventions

Summary: Background: Despite the obvious advantages, face transplantation requires strict patient selection to guarantee optimal outcomes. Therefore, it is not suitable for all patients with severe facial disfigurements. Simultaneously, conventional plastic and reconstructive surgery techniques, as well as medical spa techniques, have evolved, offering minimally invasive treatment of complex deformities. Methods: The entire face of a young woman was severely disfigured because of a mistreated juvenile acne, with severe ectropions, oral incompetence and substantial midfacial tissue defect. We are describing the reconstruction with a combination of conventional reconstructive methods, such as scar release, skin transplantation, local flaps, medical needling and lipofilling. Results: Oral competence, unhindered breathing and adequate lid closure was achieved. Previously unable to participate in social life in any meaningful way, our patient was able to reintegrate fully and take a job. Conclusion: For selected patients, combined, invasive and non-invasive conventional techniques can provide satisfying outcomes in complex facial reconstruction. Modern regenerative approaches such as lipofilling and medical needling should be considered as integral parts of treatment strategies. Keywords: Face transplantation, Facial disfigurement, Vascularized composite allotransplantatio