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S G Tullius

Publications and source records attributed to S G Tullius.

At least 19 recordsLinked to original sources
PubMed2006

Rat cytomegalovirus infection interferes with anti-CD4 mAb-(RIB 5/2) mediated tolerance and induces chronic allograft damage.

In order to assess the role of heterologous immunity on tolerance induction (TI) by signal 1 modification, the influence of rat cytomegalovirus infection (RCMVI) on TI by a non-depleting monoclonal anti-CD4 mAb (monoclonal antibody) (RIB 5/2) in a rat kidney transplant (KTx) model was investigated. Orthotopic rat KTx (Dark Agouty (DA)-->Lewis (LEW)) was performed after TI with RIB 5/2 [10 mg/kg body weight (BW); day -1, 0, 1, 2, 3; i.p. (intraperitoneal route)]. RCMVI (5x10E5 Plaque forming units [PFU] i.p.) was simultaneously conducted to KTx, 50 days after KTx, and 14 days before and after KTx. RIB 5/2 induced robust allograft tolerance even across the high-responder strain barrier. RCMVI broke RIB 5/2-induced tolerance regardless of the time of RCMVI but did not induce acute graft failure during the 120 days follow-up. RCMVI induced a significant chronic deterioration of allograft function (p<0.01) and enhanced morphological signs of chronic allograft damage (p<0.05). Cellular infiltrates and major histo-compatibility complex (MHC)-expression were more pronounced (p<0.05) in the infected groups. RCMVI induced not only RCMV-specific T-cell response but also enhanced the frequency of alloreactive T cells. RCMV interferes with anti-CD4 mAb-induced tolerance and leads to chronic allograft damage. The data we presented suggest a potentially important role of viral infections and their prophylaxis in clinical TI protocols.

Animals↗
PubMed2006

Improved long-term graft survival after HO-1 induction in brain-dead donors.

Brain death (BD) of the donor, a risk factor uniquely relevant for organs derived from cadaver donors, influences organ quality by induction of various inflammatory events. Consequently ischemia/reperfusion injury is deteriorated and acute and chronic rejections accelerated. Donor treatment might be an approach to improve the quality of the graft. The induction of heme oxygenase 1 (HO-1) has been shown to exert beneficial effects in living-donor transplantation models. Therefore, we examined the impact of donor treatment with the selective inducer of HO-1, cobalt protoporphyrin (CoPP), on organ quality and transplant outcome in a standardized BD model in a F344-->LEW kidney transplant rat model. Immediately after BD induction, donor animals were administered a single dose of CoPP (5 mg/kg) and in control groups, HO-1 activity was blocked with zinc protoporphyrin (ZnPP, 20 mg/kg). Recipients of organs from brain-dead donors treated with CoPP survived significantly better than those from untreated brain-dead donors (p < 0.05) and intra-graft analysis showed improved histology (p < 0.05). Blockade of HO-1 with ZnPP decreased the survival rates (p < 0.05) comparable to untreated brain-dead donors. Our results demonstrate that HO-1 induction by one single treatment of CoPP in brain-dead donors leads to enhanced allograft survival.

Animals↗
PubMed2005

The influence of late acute rejection episodes on long-term graft outcome after liver transplantation.

Acute cellular rejection represents the most important single risk factor for the occurrence of chronic rejection after organ transplantation. We correlated late acute rejections with the occurrence of chronic graft failure after liver transplantation. We followed 1426 liver transplants for late acute rejection episodes defined as occurring >3 months after OLT. The overall incidence of chronic rejection in our patient population was 3.7%. In summary, we observed a predictive increase of transaminase levels prior to routine biopsies among patients with histologic evidence of late acute rejections. In contrast to other organ systems, late acute rejection episodes were not associated with the occurrence of chronic graft deterioration in liver grafts.

Acute Disease↗
PubMed2005

What can be learned from brain-death models?

Brain death of the donor is an important risk factor influencing graft outcome. In addition to its nonspecific effects, it potentiates graft immunogenicity and increases host alloresponsiveness. Thus brain death in addition to other unspecific injuries such as organ procurement, preservation and consequences of ischemia/reperfusion injury, contributes towards the change of an inert organ to an immunological altered graft. Prior to engraftment, brain death initiates a cascade of molecular and cellular events including the release of proinflammatory mediators leading to cellular infiltrates. Those events may affect the incidence of both acute and chronic changes, developing and contributing to reduced graft survival. Consequently, strategies to reduce the immunogenicity or the pro-inflammatory status of the graft are becoming more attractive and might even help to improve organ quality and graft function.

Brain Death↗
PubMed2004

Regional pelvic hyperthermia as an adjunct to chemotherapy (oxaliplatin, folinic acid, 5-fluorouracil) in pre-irradiated patients with locally recurrent rectal cancer: a pilot study.

The aim of this study was to evaluate the feasibility and toxicity of a novel hyperthermic chemotherapy approach for patients with locally recurrent adenocarcinoma of the rectum. All patients were pre-irradiated (> or = 45 Gy) and had histologically proven pelvic recurrence. Hyperthermic chemotherapy was applied according to a modified 'OFF'-schedule with weekly infusions of 43 mg/m2 of oxaliplatin (i.v., 120 min), 500 mg/m2 of folinic acid (i.v., 120 min) and 2.6 g/m2 of continuous infusional 5-fluorouracil (24 h) for 6 consecutive weeks. Oxaliplatin was started in parallel to pelvic radiofrequency hyperthermia that was provided by the BSD 2000-system. A total of 67 applications were administered to nine patients and were well tolerated. A total of 55/67 (82%) chemotherapy courses were applied without dose-reduction. In 62/67 (93%) hyperthermia sessions, a treatment time of > 60 min was maintained. Tolerated power levels were on average 600 W and, thus, slightly lower than those described in curative pelvic hyperthermia schedules. Eight out of 10 episodes of severe (WHO III degrees) toxicity represented typical side-effects of the chemotherapy given (nausea n = 4, diarrhoea n = 3, neuropathy n = 1). Two severe adverse events were firstly attributable to hyperthermia (haematuria, n = 1; deterioration of a decubital ulcer, n = 1). No patient suffered WHO-disease progression during the treatment period. Two patients achieved a partial remission. It is concluded that hyperthermic chemotherapy with oxaliplatin, folinic acid and 5-FU is feasible on an outpatient basis. Overall toxicity was moderate, although hyperthermia may add side-effects to this approach. Results, moreover, suggest a relevant palliative effect in patients with pre-irradiated pelvic recurrence of rectal cancer.

Adenocarcinoma↗
PubMed2001

Preoperative antiviral treatment and postoperative prophylaxis in HBV-DNA positive patients undergoing liver transplantation.

BACKGROUND: Despite passive immunoprophylaxis a significant number of patients, especially if hepatitis B virus (HBV) DNA is positive prior to transplantation, develop HBV recurrence. This number might be reduced by lowering viral replication pretransplant with antiviral agents and by postoperative combination of antiviral agents and passive immunoprophylaxis. PATIENTS AND METHODS: A total of 74 HBV-DNA positive patients who underwent liver transplantation between 9/88 and 4/00 were analyzed retrospectively. Before lamivudine or famciclovir were available, in total 40 patients did not receive any preoperative antiviral therapy. Since 11/93, 17 patients were treated with famciclovir 1500 mg daily, after 4/96 17 patients with lamivudine 150 mg daily prior liver transplantation. Posttransplant all patients received passive immunoprophylaxis aiming at a titer of more than 100 U/liter. In the 34 patients with preoperative antiviral therapy an additional prophylaxis with the respective antiviral agent was applied. RESULTS: Under preoperative famciclovir and lamivudine 30 and 71% of patients became HBV-DNA negative, respectively. Actuarial reinfection rate 2 years after liver transplantation was 48% without antiviral prophylaxis, which was not statistically different from 55% under perioperative famciclovir therapy. In contrast only 18% developed HBV recurrence under perioperative lamivudine treatment. During both antiviral regimens neither pre nor posttransplant severe side effects were observed. CONCLUSION: Perioperative application of famciclovir is not recommendable, whereas lamivudine seems to lower recurrence rates significantly. Whether the observed effect is due to pre- or postoperative application remains to be addressed in further studies. In addition the long-term course has to be awaited.

2-Aminopurine↗
PubMed2001

[Surgical procedures and risk factors in therapy of benign multinodular goiter. A statistical comparison of the incidence of complications].

BACKGROUND: The best surgical approach for bilateral resections in the therapy of benign multinodular goiter is still controversial. METHODS: The purpose of this study was to compare different modes of resection concerning differences in complication rates and risk factors influencing the outcome. 2235 thyroid resections for multinodular goiter between 1985 and 1999 were analysed. RESULTS: When compared to bilateral subtotal resection (n = 327; 14.6%), those patients who received lobectomy and contralateral subtotal resection (n = 952; 42.6%) showed a statistically significant higher incidence of temporary hypocalcaemia (22.6% versus 15.9%) only. The "nerve at risk"-analysis demonstrated no significant difference of laryngeal nerve paralysis between the side of lobectomy and subtotal resection, respectively. In comparison to the entire patient population operations for recurrent goiters had an equal operative risk, whereas patients with goiter WHO III or an intrathoracic location had significant higher rates of temporary laryngeal nerve paralysis and hypocalcaemia. CONCLUSIONS: Lobectomy and contralateral subtotal resection offers numerous advantages concerning intraoperative variability and definitive resection of suspicious nodules. With an adequate standardized surgical technique and identification of the laryngeal nerve, the complication rate is comparable to bilateral subtotal resection.

Female↗