Late Local Recurrence after Neoadjuvant Therapy and Radical Resection for Locally Advanced Rectal Cancer

Neoadjuvant radiochemotherapy (RCT) and lately total neoadjuvant therapy (TNT) improved local recurrence rates of rectal cancer significantly compared to total mesorectal excision (TME) alone. Yet the occurrence and impact of late local recurrences after many years appears to be a distinct biological problem. We included n = 188 patients with rectal cancer after RCT and radical resection in this study; n = 38 of which had recurrent disease (sites: local (8.0%), liver (6.4%), lung (3.7%)). We found that 68% of all recurrences developed within the first two years. Four patients, however, experience recurrence >8 years after surgery. Here, we report and characterize four cases of late local recurrence (10% of patients with recurrent disease), suggesting that neoadjuvant therapy in principle delays local recurrence.

Pharmacologic Targeting of MMP2/9 Decreases Peritoneal Metastasis Formation of Colorectal Cancer in a Human Ex Vivo Peritoneum Culture Model

Simple Summary

We investigated the effects of matrix metalloproteinases (MMPs) on the peritoneal attachment of colorectal cancer cells in patient samples and in a human ex vivo peritoneum model. MMP2/9 overexpression and enhanced fibronectin cleavage occurred during peritoneal colonisation, which could be inhibited by specific MMP inhibition, thereby reducing cancer cell attachment.

Abstract

Background: Matrix metalloproteinases (MMPs) play a crucial role in tumour initiation, progression, and metastasis, including peritoneal carcinosis (PC) formation. MMPs serve as biomarkers for tumour progression in colorectal cancer (CRC), and MMP overexpression is associated with advanced-stage metastasis and poor survival. However, the molecular mechanisms of PC from CRC remain largely unclear. Methods: We investigated the role of MMPs during peritoneal colonisation by CRC cell lines in a human ex vivo peritoneum model and in patient-derived CRC and corresponding PC samples. MMP2 and MMP9 were inhibited using the small-molecule inhibitors batimastat and the specific MMP2/9 inhibitor III. Results: MMP2 and MMP9 were strongly upregulated in patient-derived samples and following peritoneal colonisation by CRC cells in the ex vivo model. MMP inhibition with batimastat reduced colonisation of HT29 and Colo205 cells by 36% and 68%, respectively (p = 0.0073 and p = 0.0002), while MMP2/9 inhibitor III reduced colonisation by 50% and 41%, respectively (p = 0.0003 and p = 0.0051). Fibronectin cleavage was enhanced in patient-derived samples of PC and during peritoneal colonisation in the ex vivo model, and this was inhibited by MMP2/9 inhibition. Conclusion: MMPs were upregulated in patient-derived samples and during peritoneal attachment of CRC cell lines in our ex vivo model. MMP2/9 inhibition prevented fibronectin cleavage and peritoneal colonisation by CRC cells. MMP inhibitors might thus offer a potential treatment strategy for patients with PC.

A human ex vivo coculture model to investigate peritoneal metastasis and innovative treatment options

Objectives

Peritoneal metastasis (PM) is commonly observed in patients with colorectal cancer (CRC). The outcome of these patients is poor, with an average survival of only six months without therapy, which requires a better understanding of PM biology and new treatment strategies.

Methods

We established and characterized a human ex vivo peritoneal model to investigate the mechanisms of peritoneal seeding and possible treatment options. For this, CRC cell lines and patient-derived tumor organoids were cultured together with human peritoneum to investigate the invasion of malignant cells and the effects of local chemotherapy.

Results

Fresh human peritoneum was cultured for up to three weeks in a stainless steel ring system, allowing for survival of all peritoneal structures. Peritoneal cell survival was documented by light microscopy and immunohistochemical staining. Further, immunohistological characterization of the tissue revealed CD3-positive T-lymphocytes and vimentin-positive fibroblasts within the peritoneum. In addition, extracellular matrix components (collagens, matrix metalloproteinases) were localized within the tissue. Coculture with CRC cell lines and patient-derived CRC organoids revealed that cancer cells grew on the peritoneum and migrated into the tissue. Coculture with CRC cells confirmed that hyperthermal treatment at 41 °C for 90 min significantly enhanced the intracellular entry of doxorubicin. Moreover, treatment with mitomycin C under hyperthermic conditions significantly reduced the amount of cancer cells within the peritoneum.

Conclusions

This human ex vivo peritoneal model provides a stringent and clinically relevant platform for the investigation of PM and for further elucidation of possible treatment options.

Hepatocellular carcinoma progression during bridging before liver transplantation

Background

Recipient selection for liver transplantation in hepatocellular carcinoma (HCC) is based primarily on criteria affecting the chance of long-term success. Here, the relationship between pretransplant bridging therapy and long-term survival was investigated in a subgroup analysis of the SiLVER Study.

Methods

Response to bridging, as defined by comparison of imaging at the time of listing and post-transplant pathology report, was categorized into controlled versus progressive disease (more than 20 per cent tumour growth or development of new lesions).

Results

Of 525 patients with HCC who had liver transplantation, 350 recipients underwent pretransplant bridging therapy. Tumour progression despite bridging was an independent risk factor affecting overall survival (hazard ratio 1.80; P = 0.005). For patients within the Milan criteria (MC) at listing, mean overall survival was longer for those with controlled versus progressive disease (6.8 versus 5.8 years; P < 0.001). Importantly, patients with HCCs outside the MC that were downsized to within the MC before liver transplantation had poor outcomes compared with patients who never exceeded the MC (mean overall survival 6.2 versus 6.6 years respectively; P = 0.030).

Conclusion

Patients with HCCs within the MC that did not show tumour progression under locoregional therapy had the best outcomes after liver transplantation. Downstaging into the limits of the MC did not improve the probability of survival.

Prognostic factors determining the long-term success of liver transplantation in patients with hepatocellular carcinoma are still under discussion. A subgroup analysis of the SiLVER trial showed that disease control under bridging therapy is strongly associated with improved prognosis in terms of overall survival. However, in tumours exceeding the limits of the Milan criteria, downstaging did not restore the probability of survival compared with that of patients within the Milan criteria.

Three dimensional cultivation increases chemo- and radioresistance of colorectal cancer cell lines

Although 2D cell cultures are commonly used to predict therapy response, it has become clear that 3D cultures may better mimic the in vivo situation and offer the possibility of tailoring translational clinical approaches. Here, we compared the response of 2D and 3D colorectal cancer (CRC) cell lines to irradiation and chemotherapy. Classic 2D cultures and 3D spheroids of CRC cell lines (CaCo2, Colo205, HCT116, SW480) were thoroughly established, then irradiated with doses of 1, 4, or 10 Gy, using a clinical-grade linear accelerator. The response was assessed by immunohistochemistry, flow cytometry, and TUNEL assays. Upon irradiation, CRC 3D spheroids were morphologically altered. After irradiation with 10 Gy, annexin V/PI staining revealed a 1.8- to 4-fold increase in the apoptosis rate in the 2D cell cultures (95% CI 3.24±0.96), and a 1.5- to 2.4-fold increase in the 3D spheroids (95% CI 1.56±0.41). Irradiation with 1 Gy caused 3- and 4-fold increases in TUNEL positive cells in the CaCo2 and HCT116 (p = 0.01) 2D cultures, respectively, compared with a 2-fold increase in the 3D spheroids. Furthermore, the 2D and 3D cultures responded differently to chemotherapy; the 3D cultures were more resistant to 5-FU and cisplatin, but not to doxorubicin and mitomycin C, than the 2D cultures. Taken together, CRC cells cultured as 3D spheroids displayed markedly higher resistance to irradiation therapy and selected chemotherapeutic drugs than 2D cultures. This in vitro difference must be considered in future approaches for determining the ideal in vitro systems that mimic human disease.

Similar complication rates for irreversible electroporation and thermal ablation in patients with hepatocellular tumors

Background To compare the frequency of adverse events of thermal microwave (MWA) and radiofrequency ablation (RFA) with non-thermal irreversible electroporation (IRE) in percutaneous ablation of hepatocellular carcinoma (HCC). Patients and methods We retrospectively analyzed 117 MWA/RFA and 47 IRE procedures (one tumor treated per procedure; 144 men and 20 women; median age, 66 years) regarding adverse events, duration of hospital and intensive care unit (ICU) stays and occurrence of a post-ablation syndrome. Complications were classified according to the Clavien & Dindo classification system. Results 70.1% of the RFA/MWA and 63.8% of the IRE procedures were performed without complications. Grade I and II complications (any deviation from the normal postinterventional course, e.g., analgesics) occurred in 26.5% (31/117) of MWA/RFA and 34.0% (16/47) of IRE procedures. Grade III and IV (major) complications occurred in 2.6% (3/117) of MWA/RFA and 2.1% (1/47) of IRE procedures. There was no significant difference in the frequency of complications (p = 0.864), duration of hospital and ICU stay and the occurrence of a post-ablation syndrome between the two groups. Conclusions Our results suggest that thermal (MWA and RFA) and non-thermal IRE ablation of malignant liver tumors have comparable complication rates despite the higher number of punctures and the lack of track cauterization in IRE.

Microfluidic enrichment, isolation and characterization of disseminated melanoma cells from lymph node samples

For the first time in melanoma, novel therapies have recently shown efficacy in the adjuvant therapy setting, which makes companion diagnostics to guide treatment decisions a desideratum. Early spread of disseminated cancer cells (DCC) to sentinel lymph nodes (SLN) is indicative of poor prognosis in melanoma and early DCCs could therefore provide important information about the malignant seed. Here, we present a strategy for enrichment of DCCs from SLN suspensions using a microfluidic device (Parsortix™, Angle plc). This approach enables the detection and isolation of viable DCCs, followed by molecular analysis and identification of genetic changes. By optimizing the workflow, the established protocol allows a high recovery of DCC from melanoma patient-derived lymph node (LN) suspensions with harvest rates above 60%. We then assessed the integrity of the transcriptome and genome of individual, isolated DCCs. In LNs of melanoma patients, we detected the expression of melanoma-associated transcripts including MLANA (encoding for MelanA protein), analyzed the BRAF and NRAS mutational status and confirmed the malignant origin of isolated melanoma DCCs by comparative genomic hybridization. We demonstrate the feasibility of epitope-independent isolation of LN DCCs using Parsortix™ for subsequent molecular characterization of isolated single DCCs with ample application fields including the use for companion diagnostics or subsequent cellular studies in personalized medicine.

Postoperative cellular stress in the kidney is associated with an early systemic γδ T-cell immune cell response

Background

Basic science data suggest that acute kidney injury (AKI) induced by ischemia-reperfusion injury (IRI) is an inflammatory process involving the adaptive immune response. Little is known about the T-cell contribution in the very early phase, so we investigated if tubular cellular stress expressed by elevated cell cycle biomarkers is associated with early changes in circulating T-cell subsets, applying a bedside-to-bench approach.

Methods

Our observational pilot study included 20 consecutive patients undergoing endovascular aortic repair for aortic aneurysms affecting the renal arteries, thereby requiring brief kidney hypoperfusion and reperfusion. Clinical-grade flow cytometry-based immune monitoring of peripheral immune cell populations was conducted perioperatively and linked to tubular cell stress biomarkers ([TIMP-2]•[IGFBP7]) immediately after surgery. To confirm clinical results and prove T-cell infiltration in the kidney, we simulated tubular cellular injury in an established mouse model of mild renal IRI.

Results

A significant correlation between tubular cell injury and a peripheral decline of γδ T cells, but no other T-cell subpopulation, was discovered within the first 24 hours (r = 0.53; p = 0.022). Turning to a mouse model of kidney warm IRI, a similar decrease in circulating γδ T cells was found and concomitantly was associated with a 6.65-fold increase in γδ T cells (p = 0.002) in the kidney tissue without alterations in other T-cell subsets, consistent with our human data. In search of a mechanistic driver of IRI, we found that the damage-associated molecule high-mobility group box 1 protein HMGB1 was significantly elevated in the peripheral blood of clinical study subjects after tubular cell injury (p = 0.019). Correspondingly, HMGB1 RNA content was significantly elevated in the murine kidney.

Conclusions

Our investigation supports a hypothesis that γδ T cells are important in the very early phase of human AKI and should be considered when designing clinical trials aimed at preventing kidney damage.

Trial registration

ClinicalTrials.gov, NCT01915446. Registered on 5 Aug 2013.

Electronic supplementary material

The online version of this article (10.1186/s13054-018-2094-x) contains supplementary material, which is available to authorized users.

DWI - histology: a possible means of determining degree of liver fibrosis?

Objectives

The aim of this study was to determine the diagnostic value of diffusion-weighted MRI of the liver at 3T to classify liver fibrosis/cirrhosis.

Methods

62 patients who underwent both histopathological examination and diffusion-weighted imaging of the liver via 3T MRI within a period of 3 months were included in the study. The Ishak score (1-6) was used to determine the degree of fibrosis: No liver fibrosis (NLF; Ishak 0, n = 16), mild liver fibrosis (MLF; Ishak 1-2, n = 23), advanced liver fibrosis (ALF; Ishak 3-5, n = 12), and liver cirrhosis (LC; Ishak 6, n = 11).

Results

The corresponding ADC values for the individual patient groups were as follows: NLF: 1123 (SD 95.8); MLF: 1032 (SD 77.6); ALF: 962 (SD 68.8); LC: 1015 (SD 60.2) mm2/s. There is a significant difference between NLF and MLF (p = 0.004) and between MLF and ALF (p = 0.022). A significant difference between patients with ALF and LC (p = 0.117) could not be found.

Conclusion

Liver fibrosis/cirrhosis lowers the ADC values of the liver parenchyma in 3T MRI. However, the degree of fibrosis can only be conditionally determined on the basis of ADC values.

Selenium-binding protein 1 is down-regulated in malignant melanoma

Selenium-binding protein 1 (SELENBP1) expression is reduced in various epithelial cancer entities compared to corresponding normal tissue and has already been described as a tumor suppressor involved in the regulation of cell proliferation, senescence, migration and apoptosis. We identified SELENBP1 to be down-regulated in cutaneous melanoma, a malignant cancer of pigment-producing melanocytes in the skin, which leads to the assumption that SELENBP1 also functions as tumor suppressor in the skin, as shown by others e.g. for prostate or lung carcinoma.

However, in vitro analyses indicate that SELENBP1 re-expression in human melanoma cell lines has no impact on cell proliferation, migration or tube formation of the tumor cells themselves when compared to control-transfected cells. Interestingly, supernatant taken from melanoma cell lines transfected with a SELENBP1 re-expression plasmid led to suppression of vessel formation of HMEC cells. Furthermore, SELENBP1 re-expression alters the sensitivity of melanoma cells for Vemurafenib treatment.

The data also hint to a functional interaction of SELENBP1 with GPX1 (Glutathione peroxidase 1). Low SELENBP1 mRNA levels correlate inversely with GPX1 expression in melanoma. The re-expression of SELENBP1 combined with down-regulation of GPX1 expression led to reduction of the proliferation of melanoma cells. In summary, SELENBP1 influences the tumor microenvironment and SELENBP1 action is functionally influenced by GPX1.

Outcome of primary percutaneous stent-revascularization in patients with atherosclerotic acute mesenteric ischemia

Background Patients with acute mesenteric ischemia (AMI) often exhibit severe co-morbidities and significant surgical risks, leading to high perioperative morbidity. Purpose To investigate the feasibility of primary percutaneous stent-revascularization (PPSR) in atherosclerotic AMI and its impact on patients' outcome. Material and Methods Retrospective analysis of 19 consecutive patients (7 women, 12 men; median age, 69 years) with AMI caused by atherosclerotic, non-embolic stenoses/occlusions of the splanchnic arteries and PPSR. Alternative minimally invasive techniques were excluded. Clinical characteristics including the Charlson Comorbidity Index adjusted by age (CCIa) and symptom duration, technical and clinical success of PPSR, clinical course, 30-day mortality, and follow-up were evaluated and compared to literature data for surgical approaches. Technical success was defined as residual stenosis of <30% in diameter. Clinical success was defined as resolution of symptoms of AMI and/or normalization of serum lactate after sole PPSR. Results The majority of patients presented with severe co-morbidities (CCIa >4 in 17 of 19 patients, 89%). Median symptom duration was 50 h. Technical and clinical success rates of PPSR were 95% (21 of 22 arteries) and 53% (10 of 19 patients). Seven patients underwent subsequent laparotomy with bowel resection in four cases. Thirty-day mortality was 42% (8 of 19 patients). Conclusion In our study population of patients with atherosclerotic AMI, severe co-morbidities, prolonged acute symptoms, and significant perioperative risks PPSR of splanchnic stenoses were technically feasible and the clinical outcome was acceptable.

CRS-HIPEC Prolongs Survival but is Not Curative for Patients with Peritoneal Carcinomatosis of Gastric Cancer

PURPOSE

Peritoneal carcinomatosis (PC) is a dismal feature of gastric cancer that most often is treated by systemic palliative chemotherapy. In this retrospective matched pairs-analysis, we sought to establish whether specific patient subgroups alternatively should be offered a multimodal therapy concept, including cytoreductive surgery (CRS) and intraoperative hyperthermic chemotherapy (HIPEC).

METHODS

Clinical outcomes of 38 consecutive patients treated with gastrectomy, CRS and HIPEC for advanced gastric cancer with PC were compared to patients treated by palliative management (with and without gastrectomy) and to patients with advanced gastric cancer with no evidence of PC. Kaplan-Meier survival curves and multivariate Cox regression models were applied.

RESULTS

Median survival time after gastrectomy was similar between patients receiving CRS-HIPEC and matched control patients operated for advanced gastric cancer without PC [18.1 months, confidence interval (CI) 10.1-26.0 vs. 21.8 months, CI 8.0-35.5 months], resulting in comparable 5-year survival (11.9 vs. 12.1 %). The median survival time after first diagnosis of PC for gastric cancer was 17.2 months (CI 10.1-24.2 months) in the CRS-HIPEC group compared with 11.0 months (CI 7.4-14.6 months) for those treated by gastrectomy and chemotherapy alone, resulting in a twofold increase of 2-year survival (35.8 vs. 16.9 %).

CONCLUSIONS

We provide retrospective evidence that multimodal treatment with gastrectomy, CRS, and HIPEC is associated with improved survival for patients with PC of advanced gastric cancer compared with gastrectomy and palliative chemotherapy alone. We also show that patients treated with CRS-HIPEC have comparable survival to matched control patients without PC. However, regardless of treatment scheme, all patients subsequently recur and die of disease.

Cyclosporine A Inhibits the T-bet-Dependent Antitumor Response of CD8(+) T Cells

Transplant recipients face an increased risk of cancer compared with the healthy population. Although several studies have examined the direct effects of immunosuppressive drugs on cancer cells, little is known about the interactions between pharmacological immunosuppression and cancer immunosurveillance. We investigated the different effects of rapamycin (Rapa) versus cyclosporine A (CsA) on tumor-reactive CD8(+) T cells. After adoptive transfer of CD8(+) T cell receptor-transgenic OTI T cells, recipient mice received either skin grafts expressing ovalbumin (OVA) or OVA-expressing B16F10 melanoma cells. Animals were treated daily with Rapa or CsA. Skin graft rejection and tumor growth as well as molecular and cellular analyses of skin- and tumor-infiltrating lymphocytes were performed. Both Rapa and CsA were equally efficient in prolonging skin graft survival when applied at clinically relevant doses. In contrast to Rapa-treated animals, CsA led to accelerated tumor growth in the presence of adoptively transferred tumor-reactive CD8(+) OTI T cells. Further analyses showed that T-bet was downregulated by CsA (but not Rapa) in CD8(+) T cells and that cancer cytotoxicity was profoundly inhibited in the absence of T-bet. CsA reduces T-bet-dependent cancer immunosurveillance by CD8(+) T cells. This may contribute to the increased cancer risk in transplant recipients receiving calcineurin inhibitors.

Liver surgery in cirrhosis and portal hypertension

The prevalence of hepatic cirrhosis in Europe and the United States, currently 250 patients per 100000 inhabitants, is steadily increasing. Thus, we observe a significant increase in patients with cirrhosis and portal hypertension needing liver resections for primary or metastatic lesions. However, extended liver resections in patients with underlying hepatic cirrhosis and portal hypertension still represent a medical challenge in regard to perioperative morbidity, surgical management and postoperative outcome. The Barcelona Clinic Liver Cancer classification recommends to restrict curative liver resections for hepatocellular carcinoma in cirrhotic patients to early tumor stages in patients with Child A cirrhosis not showing portal hypertension. However, during the last two decades, relevant improvements in preoperative diagnostic, perioperative hepatologic and intensive care management as well as in surgical techniques during hepatic resections have rendered even extended liver resections in higher-degree cirrhotic patients with portal hypertension possible. However, there are few standard indications for hepatic resections in cirrhotic patients and risk stratifications have to be performed in an interdisciplinary setting for each individual patient. We here review the indications, the preoperative risk-stratifications, the morbidity and the mortality of extended resections for primary and metastatic lesions in cirrhotic livers. Furthermore, we provide a review of literature on perioperative management in cirrhotic patients needing extrahepatic abdominal surgery and an overview of surgical options in the treatment of hepatic cirrhosis.

RORγt(+) IL-22-producing NKp46(+) cells protect from hepatic ischemia reperfusion injury in mice

BACKGROUND & AIMS

NKp46(+) cells are major effector cells in the pathogenesis of hepatic ischemia reperfusion injury (IRI). Nevertheless, the precise role of unconventional subsets like the IL-22-producing NKp46(+) cells (NK22) remains unknown. The purpose of this study was to examine the role of NK22 cells in IRI in transplantation, particularly with respect to regulation by the transcription factor ROR-gamma-t (RORγt).

METHODS

To explore the role of NK22 cells in IRI in the absence of adaptive immunity, B6.RORγt-(gfp/wt)-reporter and B6.RORγt-(gfp/gfp)-knockout (KO) mice on a Rag KO background underwent 90min partial warm ischemia, followed by 24h of reperfusion.

RESULTS

Rag KO mice that possess fully functional NKp46(+) cells, and Rag-common-γ-chain-double-KO (Rag-γc-DKO) mice that lack T, B and NKp46(+) cells, were used as controls. We found that Rag-γc-DKO mice lacking NK22 cells show more severe levels of hepatocellular damage (GPT, histological injury) when compared to both Rag-RORγt-reporter and Rag KO mice that possess NK22 cells. Importantly, Rag-RORγt-reporter and Rag KO mice undergoing IRI expressed high protein levels of both IL-22 and GFP (RORγt), suggesting a protective role for RORγt(+) NK22 cells in IRI. Therefore, we tested the hypothesis that RORγt critically protects from IRI through the induction of hepatic NK22 cells by studying Rag-Rorγt-DKO mice under IRI conditions. We found that the lack of RORγt(+) NK22 cells in Rag-Rorγt-DKO mice significantly enhanced IR-induced hepatocellular injury, a phenotype that could be reversed upon adoptive transfer of Rag-Rorγt-reporter NK22 cells into DKO mice.

CONCLUSIONS

RORγt(+) NK22 cells play an important protective role in IRI in mice.

Urinary biomarkers TIMP-2 and IGFBP7 early predict acute kidney injury after major surgery

Objective

To assess the ability of the urinary biomarkers IGFBP7 (insulin-like growth factor-binding protein 7) and TIMP-2 (tissue inhibitor of metalloproteinase 2) to early predict acute kidney injury (AKI) in high-risk surgical patients.

Introduction

Postoperative AKI is associated with an increase in short and long-term mortality. Using IGFBP7 and TIMP-2 for early detection of cellular kidney injury, thus allowing the early initiation of renal protection measures, may represent a new concept of evaluating renal function.

Methods

In this prospective study, urinary [TIMP-2]×[IGFBP7] was measured in surgical patients at high risk for AKI. A predefined cut-off value of [TIMP-2]×[IGFBP7] >0.3 was used for assessing diagnostic accuracy. Perioperative characteristics were evaluated, and ROC analyses as well as logistic regression models of risk assessment were calculated with and without a [TIMP-2]×[IGFBP7] test.

Results

107 patients were included in the study, of whom 45 (42%) developed AKI. The highest median values of biomarker were detected in septic, transplant and patients after hepatic surgery (1.24 vs 0.45 vs 0.47 ng/l²/1000). The area under receiving operating characteristic curve (AUC) for the risk of any AKI was 0.85, for early use of RRT 0.83 and for 28-day mortality 0.77. In a multivariable model with established perioperative risk factors, the [TIMP-2]×[IGFBP7] test was the strongest predictor of AKI and significantly improved the risk assessment (p<0.001).

Conclusions

Urinary [TIMP-2]×[IGFBP7] test sufficiently detect patients with risk of AKI after major non-cardiac surgery. Due to its rapid responsiveness it extends the time frame for intervention to prevent development of AKI.

Retrograde stapling of a free cervical jejunal interposition graft: a technical innovation and case report

Background

Free jejunal interposition is a useful technique for reconstruction of the cervical esophagus. However, the distal anastomosis between the graft and the remaining thoracic esophagus or a gastric conduit can be technically challenging when located very low in the thoracic aperture. We here describe a modified technique for retrograde stapling of a jejunal graft to a failed gastric conduit using a circular stapler on a delivery system.

Case presentation

A 56 year-old patient had been referred for esophageal squamous cell carcinoma at 20 cm from the incisors. On day 8 after thoracoabdominal esophagectomy with gastric pull-up, an anastomotic leakage was diagnosed. A proximal-release stent was successfully placed by gastroscopy and the patient was discharged. Two weeks later, an esophagotracheal fistula occurred proximal to the esophageal stent. Cervical esophagostomy was performed with cranial closure of the gastric conduit, which was left in situ within the right hemithorax. Three months later, reconstruction was performed using a free jejunal interposition. The anvil of a circular stapler (Orvil®, Covidien) was placed transabdominally through an endoscopic rendez-vous procedure into the gastric conduit. A free jejunal graft was retrogradely stapled to the proximal end of the conduit. Microvascular anastomoses were performed subsequently. The proximal anastomosis of the conduit was completed manually after reperfusion.

Conclusions

This modified technique allows stapling of a jejunal interposition graft located deep in the thoracic aperture and is therefore a useful method that may help to avoid reconstruction by colonic pull-up and thoracotomy.

KLRG1+ natural killer cells protect against pulmonary metastatic disease by immunosurveillance

Natural killer cells (NK cells) play a key role in cancer immunosurveillance. However, their activity is highly dependent upon their maturation stage, which in turn relates to organ distribution. Here, we discuss the role of intrinsic master transcription factors and extrinsic IL-15 signaling on NK cell-mediated immune protection against murine pulmonary metastasis.

KLRG1+ NK cells protect T-bet-deficient mice from pulmonary metastatic colorectal carcinoma

We studied the developmental and functional mechanisms behind NK cell-mediated antitumor responses against metastatic colorectal carcinoma (CRC) in mice. In particular, we focused on investigating the significance of T-box transcription factors and the immunotherapeutic relevance of IL-15 in the development and function of tumor-reactive NK cells. Pulmonary CRC metastases were experimentally seeded via an adoptive i.v. transfer of luciferase-expressing CT26 CRC cells that form viewable masses via an in vivo imaging device; genetically deficient mice were used to dissect the antitumor effects of developmentally different NK cell subsets. IL-15 precomplexed to IL-15 receptor-α was used in immunotherapy experiments. We found that mice deficient for the T-box transcription factor T-bet lack terminally differentiated antitumor CD27(low)KLRG1(+) NK cells, leading to a terminal course of rapid-onset pulmonary CRC metastases. The importance of this NK cell subset for effective antitumor immunity was shown by adoptively transferring purified CD27(low)KLRG1(+) NK cells into T-bet-deficient mice and, thereby, restoring immunity against lung metastasis formation. Importantly, immunity to metastasis formation could also be restored in T-bet-deficient recipients by treating mice with IL-15 precomplexed to IL-15 receptor-α, which induced the development of eomesodermin(+)KLRG1(+) NK cells from existing NK cell populations. Thus, contingent upon their T-bet-dependent development and activation status, NK cells can control metastatic CRC in mice, which is highly relevant for the development of immunotherapeutic approaches in the clinic.

Double deficiency for RORγt and T-bet drives Th2-mediated allograft rejection in mice

Although Th1, Th2, and Th17 cells are thought to be major effector cells in adaptive alloimmune responses, their respective contribution to allograft rejection remains unclear. To precisely address this, we used mice genetically modified for the Th1 and Th17 hallmark transcription factors T-bet and RORγt, respectively, which allowed us to study the alloreactive role of each subset in an experimental transplant setting. We found that in a fully mismatched heterotopic mouse heart transplantation model, T cells deficient for T-bet (prone to Th17 differentiation) versus RORγt (prone to Th1 differentiation) rejected allografts at a more accelerated rate, indicating a predominance of Th17- over Th1-driven alloimmunity. Importantly, T cells doubly deficient for both T-bet and RORγt differentiated into alloreactive GATA-3-expressing Th2 cells, which promptly induced allograft rejection characterized by a Th2-type intragraft expression profile and eosinophilic infiltration. Mechanistically, Th2-mediated allograft rejection was contingent on IL-4, as its neutralization significantly prolonged allograft survival by reducing intragraft expression of Th2 effector molecules and eosinophilic allograft infiltration. Moreover, under IL-4 neutralizing conditions, alloreactive double-deficient T cells upregulated Eomesodermin (Eomes) and IFN-γ, but not GATA-3. Thus, in the absence of T-bet and RORγt, Eomes may salvage Th1-mediated alloimmunity that underlies IL-4 neutralization-resistant allograft rejection. We summarize that, whereas Th17 cells predictably promote allograft rejection, IL-4-producing GATA-3(+) Th2 cells, which are generally thought to protect allogeneic transplants, may actually be potent facilitators of organ transplant rejection in the absence of T-bet and RORγt. Moreover, Eomes may rescue Th1-mediated allograft rejection in the absence of IL-4, T-bet, and RORγt.

Heart grafts tolerized through third-party multipotent adult progenitor cells can be retransplanted to secondary hosts with no immunosuppression

Multipotent adult progenitor cells (MAPCs) are an adherent stem cell population that belongs to the mesenchymal-type progenitor cell family. Although MAPCs are emerging as candidate agents for immunomodulation after solid organ transplantation, their value requires further validation in a clinically relevant cell therapy model using an organ donor- and organ recipient-independent, third-party cell product. We report that stable allograft survival can be achieved following third-party MAPC infusion in a rat model of fully allogeneic, heterotopic heart transplantation. Furthermore, long-term accepted heart grafts recovered from MAPC-treated animals can be successfully retransplanted to naïve animals without additional immunosuppression. This prolongation of MAPC-mediated allograft acceptance depends upon a myeloid cell population since depletion of macrophages by clodronate abrogates the tolerogenic MAPC effect. We also show that MAPC-mediated allograft acceptance differs mechanistically from drug-induced tolerance regarding marker gene expression, T regulatory cell induction, retransplantability, and macrophage dependence. MAPC-based immunomodulation represents a promising pathway for clinical immunotherapy that has led us to initiate a phase I clinical trial for testing safety and feasibility of third-party MAPC therapy after liver transplantation.

Alternatives to in vivo tests to detect endocrine disrupting chemicals (EDCs) in fish and amphibians--screening for estrogen, androgen and thyroid hormone disruption

Endocrine disruption is considered a highly relevant hazard for environmental risk assessment of chemicals, plant protection products, biocides and pharmaceuticals. Therefore, screening tests with a focus on interference with estrogen, androgen, and thyroid hormone pathways in fish and amphibians have been developed. However, they use a large number of animals and short-term alternatives to animal tests would be advantageous. Therefore, the status of alternative assays for endocrine disruption in fish and frogs was assessed by a detailed literature analysis. The aim was to (i) determine the strengths and limitations of alternative assays and (ii) present conclusions regarding chemical specificity, sensitivity, and correlation with in vivo data. Data from 1995 to present were collected related to the detection/testing of estrogen-, androgen-, and thyroid-active chemicals in the following test systems: cell lines, primary cells, fish/frog embryos, yeast and cell-free systems. The review shows that the majority of alternative assays measure effects directly mediated by receptor binding or resulting from interference with hormone synthesis. Other mechanisms were rarely analysed. A database was established and used for a quantitative and comparative analysis. For example, a high correlation was observed between cell-free ligand binding and cell-based reporter cell assays, between fish and frog estrogenic data and between fish embryo tests and in vivo reproductive effects. It was concluded that there is a need for a more systematic study of the predictive capacity of alternative tests and ways to reduce inter- and intra-assay variability.

Safety and feasibility of third-party multipotent adult progenitor cells for immunomodulation therapy after liver transplantation--a phase I study (MISOT-I)

BACKGROUND

Liver transplantation is the definitive treatment for many end-stage liver diseases. However, the life-long immunosuppression needed to prevent graft rejection causes clinically significant side effects. Cellular immunomodulatory therapies may allow the dose of immunosuppressive drugs to be reduced. In the current protocol, we propose to complement immunosuppressive pharmacotherapy with third-party multipotent adult progenitor cells (MAPCs), a culture-selected population of adult adherent stem cells derived from bone marrow that has been shown to display potent immunomodulatory and regenerative properties. In animal models, MAPCs reduce the need for pharmacological immunosuppression after experimental solid organ transplantation and regenerate damaged organs.

METHODS

Patients enrolled in this phase I, single-arm, single-center safety and feasibility study (n = 3-24) will receive 2 doses of third-party MAPCs after liver transplantation, on days 1 and 3, in addition to a calcineurin-inhibitor-free "bottom-up" immunosuppressive regimen with basiliximab, mycophenolic acid, and steroids. The study objective is to evaluate the safety and clinical feasibility of MAPC administration in this patient cohort. The primary endpoint of the study is safety, assessed by standardized dose-limiting toxicity events. One secondary endpoint is the time until first biopsy-proven acute rejection, in order to collect first evidence of efficacy. Dose escalation (150, 300, 450, and 600 million MAPCs) will be done according to a 3 + 3 classical escalation design (4 groups of 3-6 patients each).

DISCUSSION

If MAPCs are safe for patients undergoing liver transplantation in this study, a phase II/III trial will be conducted to assess their clinical efficacy.

Mesenchymal stem cells together with mycophenolate mofetil inhibit antigen presenting cell and T cell infiltration into allogeneic heart grafts

Donor-derived mesenchymal stem cells (MSC) can induce long-term acceptance in a rat heart transplantation model when injected prior to transplantation in combination with mycophenolate mofetil (MMF). In contrast, MSC alone cause accelerated graft rejection. To better understand these conflicting data we studied the effects of MSC and MMF on lymphocyte populations in heart allografts and secondary lymphatic organs. Allogeneic MSC injected prior to transplantation are immunogenic in this model because activated CD4+ and CD8+ cells emerged earlier in secondary lymphatic organs of MSC- and MSC/MMF-treated animals, compared to animals not treated with MSC. Consequently T cells infiltrated the grafts of MSC-only treated animals promptly causing accelerated graft rejection. However, few T cells or antigen-presenting cells (APC) infiltrated the grafts of animals treated with MSC and MMF. Consistent with this finding, intercellular adhesion molecule 1 (ICAM-1) and E-selectin was down-regulated exclusively in MSC/MMF-treated grafts, indicating that MSC together with MMF interfere with endothelial activation. Additionally, the presence of interferon-gamma (IFN-γ) enhanced MSC capabilities to suppress T cell proliferation in vitro. Interestingly, MMF did not influence serum IFN-γ levels in vivo. Together, our data indicate that MSC pre-activate T cells, but co-treatment with MMF eliminates these T cells, decreases intragraft APC and T cell trafficking by inhibiting endothelial activation, and allows IFN-γ stimulation of suppressive MSC.

Intestinal ischemia: current treatment concepts

PURPOSE

Mesenteric ischemia is a condition well-known among physicians treating patients with abdominal symptoms. Even so, mortality rates have not decreased significantly over the last decades. The purpose of this article is to review current treatment concepts of acute and chronic mesenteric ischemia.

RESULTS

Early diagnosis is one of the most important features that determine a patient's prognosis. Conventional angiography and multidetector computed tomography are therefore appropriate to quickly diagnose mesenteric ischemia, the latter being commonly more available. Once a patient presents with signs of peritonitis, instant laparotomy is indicated, and infarcted bowel segments need to be resected, followed by a second-look operation if necessary. If bowel necrosis is clinically not suspected, different approaches should be applied according to source and nature of mesenteric ischemia. Besides established surgical treatment concepts, more and more interventional procedures are developed and evaluated. However, superiority of these new techniques could only be shown for selected patient groups so far. In chronic mesenteric ischemia, interventional approaches seem to be an attractive alternative in patients who are in a condition too bad to undergo surgery. Patients with colonic ischemia are treated best in a conservative manner and by resolving the underlying cause, if identified.

CONCLUSION

Patients with acute mesenteric ischemia are still at highest risk for a fatal course of disease. New diagnostic and therapeutic developments have not been tested in larger studies yet, neither has any of these methods led to an increased survival in studies published so far. Taken together, mesenteric ischemia requires high awareness, earliest possible diagnosis, and treatment by an experienced interdisciplinary team of gastroenterologists, radiologists, and surgeons.

Hepatobiliary procedures in patients undergoing cytoreductive surgery and hyperthermic intraperitoneal chemotherapy

BACKGROUND

The long-term prognosis of patients with peritoneal malignancies has greatly improved since the introduction of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). Nevertheless, CRS can be associated with high postoperative morbidity. In this retrospective study, we analyzed the influence of hepatobiliary surgery as part of CRS on postoperative short-term patient outcome.

METHODS

Between 2005 and 2008, a total of 63 (25%) of 252 patients with peritoneal surface malignancies undergoing CRS and HIPEC required hepatobiliary surgery. Liver resection was performed in 22, resection of Glisson capsule in 39, and bile duct resection in 2 patients. The mean age of the study population was 49.3 years. Thirty-four patients (54%) were women.

RESULTS

Complete macroscopic cytoreduction (CC-0/1) was reached in 59 patients (93.7%). The median hospital stay was 18 days. Twenty-two patients developed minor complications (35%), such as moderate fever, pain, or secondary wound healing. In 21 patients (33%), severe complications occurred, most commonly pancreatitis and abdominal abscess. Three patients (4.8%) developed a biliary leakage. Of these, 2 had to be reoperated.

CONCLUSIONS

In our experience, hepatobiliary procedures have to be performed in up to one-third of patients and are associated with a low rate of specific complications, such as biliary leakages.

High volume naked DNA tail-vein injection restores liver function in Fah-knock out mice

BACKGROUND

Despite pharmaceutical treatment with NTBC (2-2-nitro-4-fluoromethylbenzoyl-1,3-cyclohexanedione), a high incidence of liver malignancies occur in humans and mice suffering from hereditary tyrosinemia type 1 (HT1) caused by mutation of the fumarylacetoacetate hydrolase (fah) gene.

METHODS

To evaluate the efficacy of a definitive treatment for HT1, we transfected fah knockout mice with naked plasmid DNA using high volume tail-vein injection. This approach was chosen to reduce the occurrence of insertional mutagenesis that is frequently observed when using other (retro-)viral vectors. To prolong gene expression, the fah gene was cloned between adeno-associated virus (AAV)-specific inverted terminal repeats (ITRs).

RESULTS

All animals treated with high volume plasmid DNA injections could be successfully weaned off NTBC and survived in the long term without any further pharmacological support. Up to 50% fah positive hepatocytes were detected in livers of naked plasmid DNA-treated animals and serum liver function tests approximated those of wild-type controls.

CONCLUSIONS

Naked plasmid DNA transfection offers a promising alternative treatment for HT1. Minimizing side-effects makes this approach especially appealing.

Mesenchymal stem cells require a sufficient, ongoing immune response to exert their immunosuppressive function

Mesenchymal stem cells (MSC) have emerged to be one of the most promising candidates for cellular immunotherapy in solid organ transplantation because the reduction of conventional immunosuppression is highly desirable. However, little is known about the details of MSC-mediated immunomodulation and their clinical relevance. To address conflicting studies about the ability of MSC to suppress or augment T-cell proliferation, we introduce a transplantation-related rat model that allows studying the influence of MSC on alloproliferation. Hearts transplanted in a fully allogeneic transplantation model (LEW to ACI) were rejected earlier when recipients were pretreated with donor MSC, indicating activation of T cells in vivo. In additional co-culture experiments, T cells were differently affected by allogeneic MSC depending on the extent of previous activation: When conditions were rendered proinflammatory by adding high concanavalin A (ConA) concentrations or proinflammatory cytokines (interferon-gamma, interleukin-2, or tumor necrosis factor-alpha), MSC inhibited proliferation. Application of low doses of ConA or anti-inflammatory cytokines like IL-10 abrogated the suppressive effect of MSC. For application of MSC in solid organ transplantation, it will be important to further describe this switch effect of MSC function.

Mesenchymal stem cells as immunomodulators after liver transplantation

Mesenchymal stem cells (MSCs) are promising candidate cells for immunomodulation therapy that are currently being tested in the preclinical and clinical setting. MSCs suppress the immune response in a variety of in vitro and disease models and may thus be of benefit for patients suffering from autoimmune disorders or transplant rejection. The mechanism by which MSCs modulate the immune response is still under thorough investigation, but it most likely involves expression of local factors such as indoleamine 2,3-dioxygenase, inducible nitric oxide synthase, and others as well as interactions with dendritic or antigen-presenting cells. Although MSCs have been evaluated in clinical phase I and II studies for graft-versus-host disease and heart, kidney, and bone disease, their introduction into solid organ transplantation is still eagerly awaited. In this short review, we summarize the current understanding of immunomodulation achieved by MSC therapies and introduce a possible outline for a clinical study that will use MSCs in the context of a calcineurin inhibitor-free induction protocol after liver transplantation.

Mesenchymal stem cells can induce long-term acceptance of solid organ allografts in synergy with low-dose mycophenolate

The induction of tolerance towards allogeneic solid organ grafts is one of the major goals in transplantation medicine. Mesenchymal stem cells (MSC) inhibit the immune response in vitro, and thus are promising candidate cells to promote acceptance of transplanted organs in vivo. Such novel approaches of tolerance induction are needed since, to date, graft acceptance can only be maintained through life-long treatment with unspecific immunosuppressants that are associated with toxic injury, opportunistic infections and malignancies. We demonstrate that donor-derived MSC induce long-term allograft acceptance in a rat heart transplantation model, when concurrently applied with a short course of low-dose mycophenolate. This tolerogenic effect of MSC is at least partially mediated by the expression of indoleamine 2,3-dioxygenase (IDO), demonstrated by the fact that blocking of IDO with 1-methyl tryptophan (1-MT) abrogates graft acceptance. Moreover we hypothesize that MSC interact with dendritic cells (DC) in vivo, because allogeneic MSC are rejected in the long-term but DC acquire a tolerogenic phenotype after applying MSC. In summary, we demonstrate that MSC constitute a promising tool for induction of non-responsiveness in solid organ transplantation that warrants further investigation in clinical trials.

Mesenteric ischemia--outcome after surgical therapy in 83 patients

BACKGROUND

Intestinal ischemia is the prime vascular emergency for the visceral surgeon. However, the diagnosis of mesenteric ischemia is difficult, the surgical options are often limited and the overall outcome is generally poor.

METHODS

We report on a single center series of 83 patients undergoing surgery for mesenteric ischemia during a 3-year period. Risk factors, clinical presentation, type and timing of imaging studies and their implications for surgical therapy and outcome are analyzed.

RESULTS

Hypertension and diabetes were the most common risk factors (68/64% of all patients). Abdominal pain was the most general symptom upon presentation to the surgical unit (73%). Two-phase, contrast-enhanced computed tomography was applied as the standard preoperative imaging modality (correct diagnosis in 69%). Bowel resections were necessary in most patients; approaches to restore blood flow by vascular surgery interventions were applied in 17 patients (20%). The overall morbidity and mortality rate in our study cohort was expectedly high (59% 1 month mortality).

CONCLUSION

The diagnosis and surgical treatment of mesenteric ischemia remains a major difficulty. We recommend preoperative CT analysis followed by an aggressive indication for early surgical exploration and bowel resection. An attempt of revascularization is justified for selected patients with limited macrovascular disease.

Ausgewählte Aspekte bei der mikrobiologischen Überwachung der Trinkwasserqualität

The new drinking water ordinance (TrinkwV 2001) entered into force in 2003. In this paper we report about experiences with monitoring microbiological quality of drinking water. Special problems, for instance requirements concerning the quality of raw water, new and "old" microbiological parameters, microbiological methods, assessment of parametric values, especially in the case of values higher than the imperative value, are also described. Possible developments in this field are discussed. The paper should support microbiological laboratories, public health officers and other public authorities in monitoring and assessment of drinking water quality.

C3-chiral tripodal amido complexes

A comprehensive study into the coordination chemistry of two C3-chiral tripodal amido ligands has been carried out. The amido ligands contain a trisilylmethane backbone and chiral peripheral substituents. The amine precursors. HC(SiMe2NH[(S)-1-phenylethyl]]3 (1) and HC[SiMe2NH[(R)-1-indanyl]]3 (2) were found to be in equilibrium in solution with the cyclic diamines HC[SiMe2N[(S)-1-phenylethyl]2](SiMe2NH-[(S)-1-phenylethyl]] (3) and HC[SiMe2NH[(R)-1-indanyl]][SiMe2NH[(R)-1-indanyl]) (4), which are generated upon ejection of one molecule of the chiral primary amine. Reaction of these equilibrium mixtures with three molar equivalents of butyllithium instantaneously gave the trilithium triamides HC[SiMe2N(Li)[(S)-1-phenylethyl]]3 (5) and HC[SiMe2N(Li)[(R)-1-indanyl]]3 (6), both of which were characterised by an X-ray diffraction study. Both lithium compounds possess a central heteroadamantane core, in which the two-coordinate Li atoms are additionally weakly solvated by the three aryl groups of the chiral peripheral substituents, the Li-C contacts being in the range of 2.65-2.73 A. Reaction of 5 and 6 with [TiCl4(thf)2] and ZrCl4 gave the corresponding amido complexes [TiCl-[HC[SiMe2N[(S)-1-phenylethyl]]3]] (7), [TiCl(HC[SiMe2N[(R)-1-indanyl]]3]] (8), [ZrCl[HC[SiMe2N[(S)-1-phenylethyl]]3]] (9) and [ZrCl[HC[SiMe2N[(R)-1-indanyl]]3]] (10), respectively. Of these, compound 7 was structurally characterised by X-ray structure analysis and was shown to possess a C3-symmetrical arrangement of the tripod ligand. The chiral anionic dinuclear complex [Li-(OEt2)4][Zr2Cl3[HC[SiMe2N[(S)-1-phenylethyl]]3]2] (11) was isolated from reaction mixtures leading to 9. An X-ray diffraction study established its dimeric structure, in which the chiral amido ligands cap the two metal centres, which are linked through three symmetrically arranged, bridging chloro ligands. Reaction of 9 and 10 with a series of alkyl Grignard and alkyllithium reagents yielded the corresponding alkylzirconium complexes. X-ray structure analyses of [Zr(CH3)[HC[SiMe2N[(S)-1-phenylethyl]]3]] (12) and [Zr(CH3)-[HC[SiMe2N)[(R)-1-indanyl]]3]] (20) established their detailed molecular arrangements. While the reaction of 12 with the aryl ketones PhC(O)R (R = CH = CHPh, iPr, Et) gave the corresponding C-O insertion products, which contain an additional chiral centre in the alkoxy group, with low stereoselectivity (0-40% de). The corresponding conversions with several aryl aldehydes yielded the alkoxo complexes with high stereoselectivity. Upon hydrolysis, the chiral alcohols were isolated and shown to have enantiomeric excesses between 68 and 82%. High stereodiscrimination was also observed in the insertion reactions of several chiral ketones and aldehydes. However, this was shown to originate primarily from the chirality of the substrate. In analogous experiments with carbonyl compounds, the ethyl- and butyl-zirconium analogues of 12 did not undergo CO insertion into the metal-alkyl bond. Instead, beta-elimination and formal insertion into the metal-hydride bond occurred. It was found that the elimination of the alkene was induced by

Performance-based measures in autism: implications for diagnosis, early detection, and identification of cognitive profiles

Provides a critical review of performance-based assessment measures in autism. Currently, performance-based measures of autism are being explored in two domains: structured play sessions and cognitive-neuropsychological assessments. Structured play sessions are designed to elicit the behavioral symptoms associated with autism to provide a consistent and valid means of early detection and diagnosis of autism across different evaluators and settings. These structured play sessions provide a supplement to diagnostic instruments based on parental report. Cognitive-neuropsychological tasks have been used to identify possible underlying cognitive impairments in autism including executive function, theory of mind, selective attention, and abstraction. Currently, cognitive tasks are useful in treatment planning but are inappropriate for diagnostic purposes. Important goals for the future will be to integrate parent-report diagnostic interviews and structured play observations and to identify a profile of cognitive impairments that are specific to pervasive developmental disorders that can be incorporated into diagnostic protocols.

Implicit and explicit memory in autism: is autism an amnesic disorder?

Medial temporal lobe amnesic disorder is characterized by an impairment in explicit memory (e.g., remembering a shopping list) and intact implicit memory (e.g., a woman seems familiar although you cannot remember having met her before). This study examined whether children with high-functioning autism have this same dissociation between explicit and implicit memory abilities. Children with autism and normal development participated in three memory tasks: one implicit task (perceptual identification) and two explicit tasks (recognition and recall). Children with autism showed intact implicit and explicit memory abilities. However, they did not show the typical pattern of recalling more items from both the beginning and end of a list and instead only recalled items from the end of the list. These results do not support the theory that high-functioning autism is a type of medial temporal lobe amnesia. However, these findings suggest that persons with autism use different organizational strategies during encoding or retrieval of items from memory.