Feedback control of arm movements using Neuro-Muscular Electrical Stimulation (NMES) combined with a lockable, passive exoskeleton for gravity compensation

Within the European project MUNDUS, an assistive framework was developed for the support of arm and hand functions during daily life activities in severely impaired people. This contribution aims at designing a feedback control system for Neuro-Muscular Electrical Stimulation (NMES) to enable reaching functions in people with no residual voluntary control of the arm and shoulder due to high level spinal cord injury. NMES is applied to the deltoids and the biceps muscles and integrated with a three degrees of freedom (DoFs) passive exoskeleton, which partially compensates gravitational forces and allows to lock each DOF. The user is able to choose the target hand position and to trigger actions using an eyetracker system. The target position is selected by using the eyetracker and determined by a marker-based tracking system using Microsoft Kinect. A central controller, i.e., a finite state machine, issues a sequence of basic movement commands to the real-time arm controller. The NMES control algorithm sequentially controls each joint angle while locking the other DoFs. Daily activities, such as drinking, brushing hair, pushing an alarm button, etc., can be supported by the system. The robust and easily tunable control approach was evaluated with five healthy subjects during a drinking task. Subjects were asked to remain passive and to allow NMES to induce the movements. In all of them, the controller was able to perform the task, and a mean hand positioning error of less than five centimeters was achieved. The average total time duration for moving the hand from a rest position to a drinking cup, for moving the cup to the mouth and back, and for finally returning the arm to the rest position was 71 s.

MUNDUS project: MUltimodal neuroprosthesis for daily upper limb support

Background

MUNDUS is an assistive framework for recovering direct interaction capability of severely motor impaired people based on arm reaching and hand functions. It aims at achieving personalization, modularity and maximization of the user’s direct involvement in assistive systems. To this, MUNDUS exploits any residual control of the end-user and can be adapted to the level of severity or to the progression of the disease allowing the user to voluntarily interact with the environment. MUNDUS target pathologies are high-level spinal cord injury (SCI) and neurodegenerative and genetic neuromuscular diseases, such as amyotrophic lateral sclerosis, Friedreich ataxia, and multiple sclerosis (MS). The system can be alternatively driven by residual voluntary muscular activation, head/eye motion, and brain signals. MUNDUS modularly combines an antigravity lightweight and non-cumbersome exoskeleton, closed-loop controlled Neuromuscular Electrical Stimulation for arm and hand motion, and potentially a motorized hand orthosis, for grasping interactive objects.

Methods

The definition of the requirements and of the interaction tasks were designed by a focus group with experts and a questionnaire with 36 potential end-users.

Five end-users (3 SCI and 2 MS) tested the system in the configuration suitable to their specific level of impairment. They performed two exemplary tasks: reaching different points in the working volume and drinking. Three experts evaluated over a 3-level score (from 0, unsuccessful, to 2, completely functional) the execution of each assisted sub-action.

Results

The functionality of all modules has been successfully demonstrated. User’s intention was detected with a 100% success. Averaging all subjects and tasks, the minimum evaluation score obtained was 1.13 ± 0.99 for the release of the handle during the drinking task, whilst all the other sub-actions achieved a mean value above 1.6. All users, but one, subjectively perceived the usefulness of the assistance and could easily control the system. Donning time ranged from 6 to 65 minutes, scaled on the configuration complexity.

Conclusions

The MUNDUS platform provides functional assistance to daily life activities; the modules integration depends on the user’s need, the functionality of the system have been demonstrated for all the possible configurations, and preliminary assessment of usability and acceptance is promising.

Up-regulation of 12(S)-lipoxygenase induces a migratory phenotype in colorectal cancer cells

12(S)-Lipoxygenase (LOX) and its product 12(S)-hydroxyeicosatetraenic (HETE) acid have been implicated in angiogenesis and tumour invasion in several tumour types while their role in colorectal cancer progression has not yet been studied. We have analysed 12(S)-LOX expression in colorectal tumours and found gene expression up-regulated in colorectal cancer specimens for which the pathology report described involvement of inflammation. Using cell line models exposed to 12(S)-HETE or over-expressing 12(S)-LOX malignant cell growth as well as tumour cell migration was found to be stimulated. Specifically, Caco2 and SW480 cells over-expressing 12(S)-LOX formed fewer colonies from sparse cultures, but migrated better in filter-migration assays. SW480 LOX cells also had higher anchorage-independent growth capacity and a higher tendency to metastasise in vivo. Knock-down or inhibition of 12(S)-LOX inhibited cell migration and anchorage-independent growth in both 12(S)-LOX transfectants and SW620 cells that express high endogenous levels of 12(S)-LOX. On the cell surface E-cadherin and integrin-β1 expression were down-regulated in a 12(S)-LOX-dependent manner disturbing cell-cell interactions. The results demonstrate that 12(S)-LOX expression in inflammatory areas of colorectal tumours has the capacity to induce an invasive phenotype in colorectal cancer cells and could be targeted for therapy.

Fibroblast growth factor receptor 3-IIIc mediates colorectal cancer growth and migration

Background:

Deregulation of fibroblast growth factor receptor 3 (FGFR3) is involved in several malignancies. Its role in colorectal cancer has not been assessed before.

Methods:

Expression of FGFR3 in human colorectal tumour specimens was analysed using splice variant-specific real-time reverse transcriptase PCR assays. To analyse the impact of FGFR3-IIIc expression on tumour cell biology, colon cancer cell models overexpressing wild-type (WT-3b and WT3c) or dominant-negative FGFR3 variants (KD3c and KD3b) were generated by either plasmid transfection or adenoviral transduction.

Results:

Although FGFR3 mRNA expression is downregulated in colorectal cancer, alterations mainly affected the FGFR3-IIIb splice variant, resulting in an increased IIIc/IIIb ratio predominantly in a subgroup of advanced tumours. Overexpression of WT3c increased proliferation, survival and colony formation in all colon cancer cell models tested, whereas WT3b had little activity. In addition, it conferred sensitivity to autocrine FGF18-mediated growth and migration signals in SW480 cells with low endogenous FGFR3-IIIc expression. Disruption of FGFR3-IIIc-dependent signalling by dominant-negative FGFR3-IIIc or small interfering RNA-mediated FGFR3-IIIc knockdown resulted in inhibition of cell growth and induction of apoptosis, which could not be observed when FGFR3-IIIb was blocked. In addition, KD3c expression blocked colony formation and migration and distinctly attenuated tumour growth in SCID mouse xenograft models.

Conclusion:

Our data show that FGFR3-IIIc exerts oncogenic functions by mediating FGF18 effects in colorectal cancer and may constitute a promising new target for therapeutic interventions.

Alanyl-glutamine infusions to patients with acute pancreatitis

In this study we infused different amounts of glutamyl-dipeptides (group 1: 1.5 g ALA-GLN + 3.5 g GLY-GLN, group 2: 20 g ALA-GLN, group 3: 40 g ALA-GLN) for a period of five days into patients with acute pancreatitis. In spite of this high amount of ALA-GLN administration we were not able to normalise the depleted glutamine pool of skeletal muscle in these catabolic patients.

Well or poorly differentiated nonfunctioning neuroendocrine carcinoma of the pancreas: a single institution experience with 17 cases

AIM

To evaluate the influence of distinguishing between well and poorly differentiated nonfunctioning neuroendocrine pancreatic carcinomas (PC).

METHOD

Six well differentiated and 11 poorly differentiated nonfunctioning neuroendocrine PC were retrospectively analyzed for differences and compared with 340 ductal PC.

RESULTS

1. There was no difference in pT categories between well differentiated and, poorly differentiated nonfunctioning neuroendocrine PC and ductal PC. 2. The rate of the pN1 category was lower in well differentiated lesions (20%) than in poorly differentiated lesions (66%) and in the ductal PC group (75%). 3. The outcome of patients with R0 resections was significantly better for well differentiated neuroendocrine PC with all patients alive than for poorly differentiated ones and for ductal PC (5-year survival rate 0% and 18%, respectively). 4. The outcome following R1/R2 resections for poorly differentiated neuroendocrine PC tended to be similar than for ductal PC (1-year survival rate 20% vs. 33%). 5. There was no difference in mean survival time (9 months) between poorly differentiated lesions and ductal PC after palliative procedures.

CONCLUSIONS

The better outcome of surgical treatment of nonfunctioning neuroendocrine PC vs. that of ductal PC was confined to well differentiated neuroendocrine lesions. For poorly differentiated lesions the outcome was as poor as for ductal PC. These results underscore the importance to distinguish between well and poorly differentiated nonfunctioning neuroendocrine PC.

[Abdominal dressing -- a new standard in therapy of the open abdomen following secondary peritonitis?]

INTRODUCTION

The management of patients with a laparostoma due to peritonitis is a challenge for every surgeon and intensivist. The goal of this study was to compare the different treatment strategies for the open abdomen: Abdominal Dressing (AD), the classic V.A.C. therapy (CV) and conventional open therapy (CT).

METHODS

Between 2001 and 2005 we identified 62 patients in 4 surgical departments in Austria who had to be treated with a laparostoma due to peritonitis. 27 patients were conventionally treated, 16 with the Classic V.A.C. therapy and 19 patients with V.A.C. abdominal dressing.

RESULTS

The mortality was 3/16 (14 %) in the AD group vs. 4/12 (21 %) patients in the CV group and 18/9 (59 %) in conventional therapy. There was no significant difference for survivors in the length of ICU stay: 26.6 +/- 23.0 days in the CT group, 34.6 +/- 30.2 days in the CV group and 38.9 +/- 27.2 days in the AD group. Apache II Score and Mannheimer Peritonitis Score showed no difference between the groups.

CONCLUSION

We found a reduction of mortality in the V.A.C. Abdominal Dressing group by approximately 40 % (AD: 14 %, CT: 59 %). Although we could identify a difference in age in our retrospective study we believe that V.A.C. Abdominal Dressing is the important factor for the different clinical outcome. These first results indicate the need for further prospective evaluation of the V.A.C. Abdominal Dressing therapy, to prove if a new standard in the therapy of the open abdomen is created.

Primary gastric B-cell lymphoma: results of a prospective multicenter study. The German-Austrian Gastrointestinal Lymphoma Study Group

BACKGROUND & AIMS

Appropriate management of primary gastric lymphoma is controversial. This prospective, multicenter study aimed to evaluate the accuracy of endoscopic biopsy diagnosis and clinical staging procedures and assess a treatment strategy based on Helicobacter pylori status and tumor stage and grade.

METHODS

Of 266 patients with primary gastric B-cell lymphoma, 236 with stages EI (n = 151) or EII (n = 85) were included in an intention-to-treat analysis. Patients with H. pylori-positive stage EI low-grade lymphoma underwent eradication therapy. Nonresponders and patients with stage EII low-grade lymphoma underwent gastric surgery. Depending on the residual tumor status and predefined risk factors, patients received either radiotherapy or no further treatment. Patients with high-grade lymphoma underwent surgery and chemotherapy at stages EI/EII, complemented by radiation in case of incomplete resection.

RESULTS

Endoscopic-bioptic typing and grading and clinical staging were accurate to 73% and 70%, respectively, based on the histopathology of resected specimens. The overall 2-year survival rates for low-grade lymphoma did not differ in the risk-adjusted treatment groups, ranging from 89% to 96%. In high-grade lymphoma, patients with complete resection or microscopic tumor residuals had significantly better survival rates (88% for EI and 83% for EII) than those with macroscopic tumor residues (53%; P < 0.001).

CONCLUSIONS

There is a considerable need for improvement in clinical diagnostic and staging procedures, especially with a view toward nonsurgical treatment. With the exception of eradication therapy in H. pylori-positive low-grade lymphoma of stage EI and the subgroup of locally advanced high-grade lymphoma, resection remains the treatment of choice. However, because there is an increasing trend toward stomach-conserving therapy, a randomized trial comparing cure of disease and quality of life with surgical and conservative treatment is needed.

Radical surgical therapy of abdominal cystic hydatid disease: factors of recurrence

A series of 74 consecutive patients (48 women, 26 men) were operated for abdominal hydatid disease between June 1949 and December 1995. The patients ranged in age from 15 to 81 years (median 49 years). In 69 cases only the liver was affected; two patients had concomitant extrahepatic disease (one spleen, one spleen and lung), and 3 had cysts in the spleen only. Cysts were multiple in 11 patients and calcified in 24. Conservative surgical procedures were used for 22 cysts in 20 patients [open partial (n = 3), open total (n = 6), closed total cystectomy (n = 9), marsupialization (n = 2), drainage (n = 2)] and radical surgical procedures for 72 cysts in 54 patients [pericystectomy (n = 41), wedge liver resection or hemihepatectomy (n = 25), splenectomy (n = 5), radical resection of a lung cyst (n = 1)]. Altogether 37 patients (50%) were given perioperative antihelmintic chemotherapy with mebendazole (18 patients) or albendazole (19 patients). Operative mortality rates were 5.0% after conservative surgery and 1.8% after radical surgery. Morbidity rates were 25.0% following conservative surgery and 24.1% following radical surgery. Antihelmintic therapy was well tolerated by all but five patients. All side effects were entirely reversible. Among the 74 patients, 60 (81.0%) were available for long-term follow-up (median 7.2 years; range 2.0-47.0 years). Recurrence of disease was seen in 9 of 60 patients at an interval of 3 months to 20 years from the first operation. The rate of recurrence was significantly lower after radical surgical procedures (p = 0.03) and after closed removal of the cyst (p = 0.04).

Treatment of unresectable, locally advanced pancreatic adenocarcinoma with combined radiochemotherapy with 5-fluorouracil, leucovorin and cisplatin

The aim of the study was to evaluate the effectiveness and safety of a combined treatment modality including systemic chemotherapy with 5-fluorouracil (FU), leucovorin, cisplatin and external beam radiotherapy in patients with locally advanced pancreatic cancer. Systemic chemotherapy consisted of FU 400 mg m(-2) and leucovorin 20 mg m(-2) both given as intravenous bolus injection on days 1-4, plus cisplatin 20 mg m(-2) administered as 90-min infusion on days 1-4. Treatment courses were repeated every 4 weeks x 6 unless prior evidence of progressive disease. Radiation therapy using megavolt irradiation of > or = 6 MV photons with a 3- or 4-field technique was delivered during the second and third chemotherapy course, that was reduced in dose by 25%. Between October 1994 and July 1996, a total of 38 patients were entered onto this trial, all of whom were assessable for toxicity and survival. Eighteen of these (47%) had objective remissions to combined radiochemotherapy, including four CR (11%), 13 (34%) had stable disease and seven patients (18%) showed tumour progression during treatment. The median progression-free interval of the entire study population was 10 months (range 3-32), and median overall survival was 14.0 months (range 3-45+ months); 53% of all patients were alive at 12 months, and 18% of patients were alive at 24 months respectively. Severe haematological side-effects comprised neutropenia in 18%, thrombocytopenia in 8% and anaemia in 11%. The most frequent non-haematological side-effects were nausea/vomiting (WHO grade 3: 18%), and diarrhoea (grade 3: 13%). This combined radiochemotherapy regimen was tolerable and effective in patients with locally advanced pancreatic cancer. Since therapeutic results, in fact, compare favourably with other series, including surgical treatment of potentially resectable tumours, further evaluation of combined treatment modalities in the neoadjuvant setting seems warranted.

The relationship between photosynthesis and a mastoparan-induced hypersensitive response in isolated mesophyll cells

The G-protein activator mastoparan (MP) was found to elicit the hypersensitive response (HR) in isolated Asparagus sprengeri mesophyll cells at micromolar concentrations. The HR was characterized by cell death, extracellular alkalinization, and an oxidative burst, indicated by the reduction of molecular O2 to O2. To our knowledge, this study was the first to monitor photosynthesis during the HR. MP had rapid and dramatic effects on photosynthetic electron transport and excitation energy transfer as determined by variable chlorophyll a fluorescence measurements. A large increase in nonphotochemical quenching of chlorophyll a fluorescence accompanied the initial stages of the oxidative burst. The minimal level of fluorescence was also quenched, which suggests the origin of this nonphotochemical quenching to be a decrease in the antenna size of photosystem II. In contrast, photochemical quenching of fluorescence decreased dramatically during the latter stages of the oxidative burst, indicating a somewhat slower inhibition of photosystem II electron transport. The net consumption of O2 and the initial rate of O2 uptake, elicited by MP, were higher in the light than in the dark. These data indicate that light enhances the oxidative burst and suggest a complex relationship between photosynthesis and the HR.

[Hypersensitivity vasculitis causing an acute abdomen]

The members of a family of four persons suffered acute gastroenteritis after eating a meal consisting of chicken. While three of them recovered rapidly, the 18-year old son developed an acute abdomen which had to be treated surgically and led to a complicated stay at the intensive care unit. Intraoperatively, a mild insignificantly inflamed appendix and an obscure segmental inflammatory process of the small bowel with local peritonitis were seen; this required an appendectomy and a peritoneal lavage. The development of bacterial peritonitis with multiple organ dysfunction required several surgical revisions with an open abdominal toilet treatment. Histological examination of the resected appendix specimen showed a severe primary fibrinoid necrotizing vasculitis with epitheloid-granulomatous reaction. Diseases such as Panenteritis nodosa, Wegener's disease and Churg-Strauss's syndrome were excluded by negative serology. By a process of exclusion, a hypersensitivity vasculitis was diagnosed and treated successfully with a high-dose cortisone regime.

Combined intravenous and intraperitoneal chemotherapy with fluorouracil + leucovorin vs fluorouracil + levamisole for adjuvant therapy of resected colon carcinoma

Adjuvant chemotherapy with fluorouracil (FU) and levamisole or FU/leucovorin (LV) has been established as effective adjuvant treatment for patients with stage III colon cancer. Among several other promising treatment strategies in resected colon cancer, intraperitoneal anti-cancer drug administration with its appealing rationale of counteracting microscopic residual disease on peritoneal surfaces and occult metachronous liver metastases by achieving high intraportal drug concentrations has not yet undergone sufficient clinical evaluation. To determine whether a combination of this locoregional therapeutic concept with systemic intravenous administration of FU/LV would yield better results than conventional adjuvant chemoimmunotherapy with FU/levamisole, the present randomized study was initiated. A total of 241 patients with resected stage III or high-risk stage II (T4N0M0) colon cancer were randomly assigned to 'standard therapy' with FU and levamisole, given for a duration of 6 months, or to an investigational arm, consisting of LV 200 mg m(-2) plus FU 350 mg m(-2), both administered intravenously (days 1-4) and intraperitoneally (days 1 and 3) every 4 weeks for a total of six courses. In patients with stage II disease, no significant difference was noted between the two arms after a median follow-up time of 4 years (range 2.5-6 years). Among 196 eligible patients with stage III disease, however, a comparative analysis of the two treatment groups suggested both an improvement in disease-free survival (P = 0.0014) and a survival advantage (P = 0.0005), with an estimated 43% reduction in mortality rate (95% confidence interval 26-70%) in favour of the investigational arm. In agreement with its theoretical rationale, combined intraperitoneal and intravenous FU/LV was particularly effective in reducing locoregional tumour recurrences with or without liver or other organ site involvement (9 vs 25 patients in the FU/levamisole arm; P = 0.005). Treatment-associated side-effects were infrequent and generally mild in both arms, although a lower rate of severe (WHO grade 3) adverse reactions was noted in patients receiving locoregional plus intravenous chemotherapy (3% vs 12%; P = 0.01). The results of this trial suggest that combined intraperitoneal plus systemic intravenous chemotherapy with FU/LV is a promising adjuvant treatment strategy in patients with surgically resected stage III colon carcinoma.

Fluorouracil plus racemic leucovorin versus fluorouracil combined with the pure l-isomer of leucovorin for the treatment of advanced colorectal cancer: a randomized phase III study

PURPOSE

To compare the efficacy and toxicity of fluorouracil (FU) and racemic leucovorin (d,l-LV) versus FU combined with the l-isomer of leucovorin (l-LV) in the treatment of advanced colorectal cancer.

PATIENTS AND METHODS

A total of 248 patients with advanced measurable colorectal cancer previously unexposed to chemotherapy were randomly assigned to treatment with either FU (400 mg/m2/d by intravenous [I.V.] infusion for 2 hours) and racemic LV (100 mg/m2/d by I.V. bolus injection) given for 5 consecutive days, or the combination of FU and the pure l-isomer of LV using the same dose schedule. In both treatment arms, courses were administered every 28 days if toxicity allowed for a total of 6 months, unless evidence of tumor progression was documented earlier.

RESULTS

There were no significant differences between the FU/racemic LV and the FU/l-LV arm in the overall response rate (25% v 32%), duration of response (7.2 v 8.0 months), median time to progression or death (6.25 v 8.0 months), or median overall survival time (14.5 v 15.0 months). Except for minor myeloid toxic effects associated with FU/l-LV, there was also no significant difference in terms of adverse reactions. Gastrointestinal symptoms, specifically mucasitis and diarrhea, were less frequent and less severe in both treatment arms compared with other trials with FU/racemic LV reported in the literature, which might be because of the prolonged administration of FU used in both arms.

CONCLUSION

The combination of FU/l-LV produced response rates, response durations, and survival times similar to those with FU/d,l-LV. Biochemical modulation of FU by either pure l-LV or racemic LV thus appears to result in equivalent clinical efficacy.

Cytogenetic findings in colorectal cancer mirror multistep evolution of colorectal cancer

Successful cytogenetic analysis was performed on tumor material from 26 patients with resectable colorectal cancer. 9 women and 17 men, aged 43 to 92 years, median 67 years. Clonal anomalies were found in twenty patients; five tumors showed mainly slight numerical changes such as trisomy 7 and loss of Y (2 cases). The remaining 15 tumors had highly complex karyotypes. The mainline was near diploid in six cases (5/6 tumors of the proximal colon), near triploid in four and near tetraploid in five tumors. Loss of chromosomes was most frequently observed with chromosomes 2, 5, 18, 20, and Y, the most frequently gained chromosomes were 7, 8, 13, 15, and X. Structural aberrations affected all chromosomes, except Y. The most frequently rearranged bands were 5q21, 7p15, 9p21, 13q11, 16p12, 17p13, 18q21, 21q11. Anomalies of chromosomes 5, 17, and 18 occurred concomitantly in 9/20 patients. All patients with deletions of 17p (n = 6) had near tetraploid karyotypes with high cell to cell variability and a median of nine structural aberrations (p < 0.007); four of them presented with parenchymal metastases at the time of surgery. Tumors of the proximal part of colon were with one exception diploid or near diploid, but no specific pattern of aberrations was detectable. However, it appears noteworthy that of the six patients with tumors of the ascending colon, three tumors had deletions at 16p12 and the affected patients had a short duration of survival. The tumor karyotypes of patients with parenchymal metastases revealed a trend to greater complexity of numerical and structural aberrations. Changes involving 8p22 or loss of chromosomes 8 were found in tumors of all parts of the colon and potentially associated with an unfavorable prognosis (4/7 decreased patients showed such changes).

Limb salvage in periacetabular sarcomas: review of 21 consecutive cases

The oncologic and functional outcome was reviewed in 21 consecutive patients who underwent limb salvaging surgery for periacetabular sarcoma using a new surgical approach and different types of reconstruction between 1972 and 1990. Histologic diagnosis in 86% showed osteosarcomas, chondrosarcomas, and Ewing's tumors. Age ranged from 10.0 to 61.5 years (mean age, 32.9 years). The resection margin was wide in 15 patients but marginal in 2 patients and intralesional in 4 patients. All of the latter patients died of their disease. In all cases where 3-dimensional imaging was used, wide resection margins could be achieved, whereas this was possible only in 50% of the cases with conventional imaging techniques. Seven patients died of their disease 3 to 15 months after surgery, 2 died of chemotherapy induced sepsis, and 2 patients died perioperatively. At followup, 8 patients had no evidence of disease (mean, 57.6 months; range, 12-190 months), and 2 patients were alive with disease. Fourteen patients could be observed for at least 12 months (mean, 41.1 months) and were functionally evaluated according to Enneking's criteria. If extensive resection was necessary, the best results were found if the defect had been reconstructed with a custom made prosthesis. The results were only satisfactory after implantation of saddle prostheses and poor with allografts or when no reconstruction of the bone defect was done.

Acute effects of insulin-like growth factor I on interorgan glucose and lactate flux in protein-catabolic dogs

Insulin-like growth factor-I (IGF-I) is a potent protein-anabolic hormone with a glucose-lowering effect and is therefore a possible agent for treating catabolic patients. In this study we investigated the effect of recombinant human (rh) IGF-I on the interorgan flux of glucose under hypo- and normoglycemic conditions in catabolic, anaesthetized, and catheterized dogs. We administered a primed (40 micrograms/kg) continuous (1.5 micrograms.kg-1.min-1) infusion of rhIGF-I (Kabi Biopharma, Stockholm, Sweden) for 180 min together with either a saline (0.9% NaCl) or an amino acid solution (2.2 mg AA.kg-1.min-1 solution of Vamin, Kabi Nutrition, Stockholm, Sweden). RhIGF-I administration lowered plasma glucose levels for approximately 50% of the baseline (P < 0.001) and stimulated glucose uptake from skeletal muscle about twofold (P < 0.01), but did not modify glucose balances across the gut and liver. The same effects were found when infusing rhIGF-I together with AA. A co-infusion of rhIGF-I and glucose to maintain normoglycemic conditions stimulated glucose uptake from skeletal muscle by about fivefold (P < 0.001) and glucose uptake across the gut by about 50%, but reduced the hepatic glucose liberation (-65%; P < 0.01). The rhIGF-I infusion did not alter arterial lactate levels, but stimulated lactate release from skeletal muscle (P < 0.05) and lactate uptake across the liver (P < 0.05). We conclude that rhIGF-I reduces plasma glucose levels mainly by stimulating glucose uptake across skeletal muscle.(ABSTRACT TRUNCATED AT 250 WORDS)

Phase I/II trial of dexverapamil, epirubicin and granulocyte/macrophage-colony-stimulating factor in patients with advanced pancreatic adenocarcinoma

A group of 28 previously untreated patients with locally advanced or metastatic adenocarcinoma of the pancreas were entered in this phase I/II study. Treatment consisted of oral dexverapamil 1000-1200 mg/day for 3 days, epirubicin given as an intravenous bolus injection on day 2 with a starting dose of 90 mg/m2, and 400 micrograms granulocyte/macrophage-colony-stimulating factor (GM-CSF) administered subcutaneously from day 5 through 14. Epirubicin dose escalation levels were 90, 105, 120 and 135 mg/m2. Consecutive cohorts of 4-8 patients were planned at each dose level. Treatment cycles were repeated every 3 weeks. Haematological toxicity, specifically granulocytopenia constituted the dose-limiting toxicity with a maximum tolerated dose of 120 mg/m2 for epirubicin. Despite routine supportive therapy with GM-CSF, 4, 2, and 5 patients experienced grade 4 granulocytopenia during their first two treatment courses at levels of 105, 120, and 135 mg/m2 respectively. Non-haematological toxicity was uncommon, generally modest, and did not demonstrate a clear relationship with the anthracycline dose. Dexverapamil-related cardiovascular symptoms occurred frequently, but they never resulted in serious toxicity requiring active medical intervention or permanent discontinuation of therapy. Of the 28 patients, 9 achieved partial reponses to this therapy. The recommended dose of epirubicin for this regimen with dexverapamil and GM-CSF is 120 mg/m2 every 3 weeks. Therapeutic results suggest this regimen to be an effective and tolerable treatment strategy in pancreatic cancer, which should be evaluated further.

Resistance of nitrogen metabolism to growth hormone treatment in the early phase after injury of patients with multiple injuries

OBJECTIVES AND DESIGN

Several studies have shown an anticatabolic effect of recombinant human growth hormone (rhGH) in surgical patients. We investigated, in a prospective, randomized, double blind, and placebo-controlled study, the effect of r-hGH on hormone and nitrogen metabolism in 14 patients with multiple injuries in the early phase of injury.

MATERIALS AND METHODS

All patients were treated in the intensive care unit, had mechanical ventilation, and were highly catabolic, with a mean daily nitrogen loss of 13.2 +/- 1.8 g. r-hGH was given subcutaneously (once a day, at 8 PM) in a dosage of 0.2 IU/kg.d for seven days, starting on the second day after injury.

RESULTS

Administration of r-hGH evoked a significant increase in plasma concentrations of GH, insulin-like growth factor-I (IGF-I), and insulin-like growth factor binding-protein-3 (IGFBP-3). No significant differences were found for either daily or cumulative nitrogen balances (-103.1 +/- 14 g for patients receiving r-hGH and -92.1 +/- 18.1 for those with placebo). r-hGH therapy did not affect skeletal muscle extracellular water, nor did it affect plasma or muscle concentrations of total free amino acids or glutamine. Plasma albumin, prealbumin, and retinol-binding protein concentrations were also unchanged by r-hGH therapy, as were the urinary excretion of potassium and urea.

CONCLUSIONS

We conclude that elevated plasma levels of GH, insulin, and IGF-I are unable to effect a protein anabolic drive in patients with multiple injuries during the early postinjury phase and assume that this r-hGH resistance to nitrogen metabolism takes place at the level distal to IGF-I.

Acute effects of insulin-like growth factor I on inter-organ amino acid flux in protein-catabolic dogs

The effects of acute administration of human recombinant insulin-like growth factor-I (rhIGF-I) on amino acid (AA) flux between hindlimbs, liver and gut were investigated in anaesthetized post-operative dogs. rhIGF-I produced about a 10-fold increase in plasma IGF-I concentrations above baseline values (P < 0.001), increased the plasma levels of glucagon and adrenaline (P < 0.05), and evoked a fall in plasma glucose (-55 +/- 8%; (P < 0.001) and plasma total AA levels (-23 +/- 8%; P < 0.05). AA flux in post-absorptive dogs under NaCl infusions was characterized by an efflux of AA from the hindlimbs (as a result of the protein-catabolic situation), an equal AA balance across the gut and an AA uptake by the liver. The administration of rhIGF-I increased hepatic AA uptake in the NaCl group from 3.51 +/- 0.8 to 7.5 +/- 0.4 mumol/min per kg (P < 0.01) and in the AA-infused group from 16.8 +/- 0.6 to 22.4 +/- 1.5 mumol/min per kg (P < 0.05), but did not influence the AA balance across hindlimbs and gut. Glucose infusions normalized the plasma concentrations of counter-regulatory hormones without influencing the inter-organ AA balances. We conclude that hypoaminoacidaemia caused by rhIGF-I infusions is the result of a stimulated AA uptake by the liver, but is unrelated to alterations of AA exchange across the hindlimbs.

Dacron versus polytetrafluoroethylene for Y-aortic bifurcation grafts: a six-year prospective, randomized trial

BACKGROUND

A prospective, randomized trial was conducted to compare Dacron with expanded polytetrafluoroethylene (ePTFE) in reconstructive aortoiliac surgery. No comparable trial with a prospective, randomized design with a comparable number of patients or an equal long-term follow-up period can be found in the literature.

METHODS

Between 1984 and 1989, 165 patients were randomized for either Dacron or ePTFE on the basis of age, sex, indication for surgery, diabetes, nicotine consumption, runoff, and operative approach. The two groups were well matched for randomization criteria, as well as the incidence of aneurysms.

RESULTS

No statistically significant difference was found between the two graft materials in terms of patency rates (corrected 3-year patency rates: Dacron = 95% vs ePTFE = 95%; Breslow, p = 0.83; Mantel-Cox, p = 0.74). Subgroup analysis comparing long-term patency rates of the two graft materials and relating them to poor runoff, good runoff, aneurysms, and arterial occlusive disease also failed to show any significant differences between ePTFE and Dacron. Early graft failure (n = 6; 3.6% of the patient population; p = 0.045) and severe abdominal graft infection (n = 3; 1.8% of the total population) were seen only in ePTFE grafts. However, these did not affect the corrected long-term patency rate of ePTFE grafts. There were five late graft failures with PTFE (3.0%) and four with Dacron (2.4%).

CONCLUSIONS

Graft materials currently available for aortoiliac repair were comparable in terms of corrected long-term patency rates. The alleged advantages of PTFE were not confirmed by our data. PTFE grafts were associated with a higher rate of complications, and more redo operations were required to duplicate the results obtained with Dacron.

Effect of alpha-ketoglutarate infusions on organ balances of glutamine and glutamate in anaesthetized dogs in the catabolic state

1. The salt complex of L-(+)-ornithine and alpha-ketoglutarate (2-oxoglutarate) has recently been proposed for the treatment of patients in the catabolic state. As yet, it is unclear which of the two substrates (ornithine or alpha-ketoglutarate) is responsible for the anticatabolic effect. We infused alpha-ketoglutarate into anaesthetized post-operative dogs in order to investigate whether infusion of alpha-ketoglutarate affects the flux of glutamine and glutamate between skeletal muscle and the splanchnic bed. We used three infusion rates: 3, 10 and 20 mumol min-1 kg-1. A steady state of alpha-ketoglutarate concentration in arterial whole-blood was attained only when the infusion rate was 3 mumol min-1 kg-1. 2. Arterial whole-blood concentrations of alpha-ketoglutarate were 8.8 +/- 1.2 mumol/l in the basal period and rose to 208 +/- 41, 344 +/- 61 and 1418 +/- 315 mumol/l after 60 min infusions of alpha-ketoglutarate at 3, 10 and 20 mumol min-1 kg-1, respectively. 3. alpha-Ketoglutarate uptake was measured in skeletal muscle, liver, gut and kidneys in the basal period and during the infusion of alpha-ketoglutarate. The net uptake of infused alpha-ketoglutarate was highest in the skeletal muscle, followed by kidneys, liver and gut. 4. The alpha-ketoglutarate load increased the muscular tissue content of alpha-ketoglutarate from 49.5 +/- 5 to 142 +/- 15 nmol/g of dry substance (P less than 0.001), but did not alter the muscular glutamate or glutamine contents.(ABSTRACT TRUNCATED AT 250 WORDS)

Current trends in the management of carcinoma of the pancreatic head

Between 1965 and 1987, 783 patients were treated for ductal adenocarcinoma. Of these, 59% had carcinoma of the pancreatic head and 22% presented with carcinoma of the body or tail. In 19% of the cases the entire organ was involved. Two hundred and twenty-six patients (25.5%) underwent exploratory laparotomy; 420 patients (55%) had palliative operations, and 137 (18.5%) were resected for cure. In the past 3 years the resection rate increased from an original 18.5% to 28% (43 resective procedures in 153 patients). In 37 of the 137 patients (28%) surgery had to be extended to the portal vein, the superior mesenteric vein, the kidneys, adrenals, colon, stomach, liver and lymph nodes to ensure adequate radicality. At the same time in-hospital mortality (including deaths after extended procedures) dropped to 7%. Of the 137 patients resected for cure, 47% were alive at 1 year, 22% at 2 years, 12% at 3 years, 7% at 4 years, and 5% at 5 years. Mean survival time excluding in-hospital deaths was 18.65 months. In the first 15 months after surgery there was no difference in survival between standard resections and extended resections. Patients undergoing partial pancreaticoduodenectomy fared significantly better (p less than 0.01; Mantel) than those who had total resections, in terms of both median survival (10.8 versus 5.4 months) and mean survival (19.0 versus 7.82 months).(ABSTRACT TRUNCATED AT 250 WORDS)

Plasma glutamate--a prognostic marker of cancer and of other immunodeficiency syndromes?

Elevated plasma levels of glutamate (GLU) have been reported to occur in patients with malignancies and other immunodeficiency syndromes (IDS). To evaluate, whether GLU is useful as prognostic indicator, the plasma concentrations were determined in patients with colorectal carcinoma (CRC), with breast cancer (BRC), and with HIV-infection (HIV). The results were correlated with the disease-stages, and compared with data obtained from patients with benign diseases of the same organ, as well as from sex-matched healthy volunteers. GLU concentrations (volunteers: 27.4 +/- 17.6 mumol/l) were elevated in all BRC patients (range of mean values: 53.5-83.2 mumol/l), in CRC patients with T2-T4-tumours (means: 46.8-85.9), and in HIV+ patients of stage WR 5, 6 (means: 53.9-69.7 mumol/l). All CRC- and BRC-patients with metastases showed highly significant elevations of GLU concentrations (p less than 0.001), but there were no direct correlations between disease stages and GLU levels. Pre-operative patients with benign diseases (diverticulitis, adenoma = GID; and mastopathy = MTP) showed increased GLU levels, which were comparable to those of the tumour patients. The glutamine/GLU ratios (volunteers: 19.3 +/- 15.0) were decreased only in HIV-WR 6 (7.6 +/- 2.1), and BRC-stage 4 (8.0 +/- 1.7). From these results we deduce that the plasma GLU concentrations do not allow a discrimination either between patients with malignancies and without, and between persons of different disease stages.

Glutamine-containing dipeptides as infusion substrates in the septic state

Recently a relationship has been postulated between lowered intracellular glutamine concentrations in the skeletal muscle and the rate of protein synthesis. We investigated the effect of 48 hours of parenteral nutrition supplemented with a solution containing glutamine in free or dipeptide form (alanylglutamine or glycylglutamine) on the intracellular glutamine pool in skeletal muscle and on the hind limb exchange of glutamine in dogs with sepsis after surgery. Before surgery, dogs were fasted for 48 hours. We used glutamine dipeptides as sources because they remain stable in an aqueous solution. Nutrition solutions were isocaloric (17.8 kcal/kg body weight/day on day 1 and 35.6 kcal/kg on day 2) and isonitrogenous (0.33 gm nitrogen/kg body weight/day), providing 2.6 mmol/kg body weight/day as glutamine source. During starvation, muscular free glutamine levels decreased by 41% to 10.4 mmol/L (p less than 0.001). On the second postoperative day the dogs had lowered plasma protein levels, a sharp drop in platelet count, an increase in the leukocyte count, and positive blood cultures. None of the solutions investigated in this study was effective in repleting the glutamine pool during 2 days of postoperative nutrition (11 +/- 2.0 mmol/L without glutamine, 10.3 +/- 2.2 mmol/L with glutamine plus alanine, 9.9 +/- 1.6 mmol/L with alanylglutamine, 7.5 +/- 1.1 mmol/L with glutamine plus glycine, and 7.2 +/- 1.2 mmol/L with glycylglutamine, respectively). The release of glutamine from the hindquarter was 631 +/- 38 nmol/kg body weight/min in the control group and decreased significantly in dogs receiving alanylglutamine (13.5 +/- 45 nmol/kg body weight/min; p less than 0.001) or the constituent amino acids (265 +/- 66 nmol/kg body weight/min; p less than 0.01) but was unchanged in dogs receiving glycylglutamine or glutamine plus glycine. We conclude that the duration and dosage of glutamine administration (equivalent to 26 gm glutamine per day in a patient weighing 70 kg) used in this study are not sufficient to restore glutamine deficiency of the skeletal muscle in the depleted state.

Eating difficulties in patients with probable dementia of the Alzheimer type

Seventy-three institutionalized patients suffering from probable dementia of the Alzheimer type (DAT) were surveyed for the presence of eating difficulties. Among 71 patients fed by natural means four different groups emerged: (1) patients who fed themselves (n = 17, 23.9%), (2) patients who had to be fed but posed no other eating problem (n = 13, 18.3%), (3) patients who refused food although they were able to swallow it (n = 18, 25.4%), and (4) patients who choked on liquid and/or solid food, some of whom also refused food (n = 23, 32.4%). Patients who fed themselves were in a less advanced stage of the disease than those who did not, and their average body weight was equal to the ideal weight. The remaining three groups, ie, those with different eating problems, did not differ in mean severity of DAT, and their body weights were significantly lower. The mortality rate during 2 years following the survey was similar in all four groups of patients, although tube feeding was used in only one case. The mortality rate was also similar in patients whose body weights were 20% or more below the median weight for their age, and in patients whose relative body weight was higher. The results of this study suggest that eating difficulties occur in a majority of institutionalized DAT patients, but can be managed without resorting to tube feeding.

Infusion of dipeptides as nutritional substrates for glutamine, tyrosine, and branched-chain amino acids in patients with acute pancreatitis

In this study we investigated the effect of a total parenteral nutrition supplemented with synthetic dipeptides on plasma and muscle amino acid metabolism in four patients with acute pancreatitis. We infused an amino acid solution containing alanylglutamine, glycylglutamine, glycylvaline, glycylisoleucine, glylcylleucine, and glycyltyrosine for a period of five days in daily dosages of 10.3, 22.1, 68.8, 37.2, 42.5, and 15.7 mmol, respectively. The plasma levels remained below 100 mumol/L for all infused dipeptides. The plasma concentrations of alanylglutamine were not measurable. Mean peptide urine excretion remained below 5%, with the exception of glycylglutamine (8.5% +/- 5.1%). Arteriovenous concentration differences of the dipeptides across the leg were not significantly different from zero, indicating that the infused dipeptides have no important role in the nitrogen exchange of skeletal muscle. A marked intracellular glutamine deficiency in skeletal muscle was found in all four patients (5.1 +/- 0.6 mmol/L v 19.5 +/- 0.8 in healthy subjects) before infusion. Intracellular glutamine concentration was significantly higher after the infusion period (5.1 +/- 0.7 v 9.5 +/- 1.8 mmol/L, P greater than .05), but no normalization of the intracellular glutamine levels was achieved by the infusion of the two glutamine-containing peptides. We conclude that peptides are well metabolized as substrates for parenteral nutrition in catabolic patients. Furthermore, the infusion of glutamine peptides caused a significant increase in intracellular glutamine levels; however, the dosage of glutamine peptides was too low to normalize the muscular glutamine concentrations.

Influence of alanylglutamine infusion on gastrointestinal glutamine and alanine metabolism in anesthetized dogs

In this study we administered an infusion of alanylglutamine (10 mumol/kg.min) for 60 minutes to postoperative anaesthetized dogs with catheters placed in the portal and hepatic veins. Arterial plasma levels of alanylglutamine were 83 +/- 27 mumol/L 20 minutes after the onset of the infusion and remained constant throughout the infusion period. Plasma levels of glutamine and alanine approximately doubled compared with preinfusion levels, indicating a release of these amino acids from the dipeptide. The halflife of alanylglutamine, calculated after bolus injection of 2 g, was 1.7 +/- 0.5 minutes. Alanylglutamine was extracted from the liver and the gut (0.9 +/- 0.3 and 0.5 +/- 0.1 mumol/kg.min, respectively). In the basal period (without infusion of alanylglutamine), a glutamine uptake by the liver and the intestine was found. Alanine was taken up by the liver and released from the gut. The infusion of alanylglutamine significantly increased the hepatic uptake of glutamine and alanine (from 0.8 +/- 0.2 to 3.8 +/- 0.6 and from 3.0 +/- 0.4 to 7.5 +/- 0.7 mumol/kg.min respectively; P less than .01) and did not significantly change the intestinal uptake of glutamine and the release of alanine. We conclude that the infusion of alanylglutamine markedly influences the hepatic metabolism of glutamine and alanine, probably via the increased arterial and portal levels of glutamine and alanine.

Groin infections following vascular surgery: obturator bypass (BYP) versus "biologic coverage" (TRP)--a comparative analysis

Deep infections in the groin complicating vascular surgical procedures pose a serious problem, in the treatment of which two alternative methods are available: (1) Removal of the graft and the construction of an extra anatomic bypass (obturator canal bypass, BYP), or (2) retaining the graft and achieving healing of the infected wound by various biological materials, such as omentum or an inferior rectus abdominis muscle flap (TRP). The probability of patient and limb survival was estimated by the Kaplan-Meier method and possible differences between both groups checked using Breslow's and Mantel's tests. No statistically significant differences were found and a variety of factors with potential influence on the outcome were considered equally balanced. However, as soon as the catastrophic event of infection plus haemorrhage enforced emergency surgery, the incidence of success differed markedly: in the BYP group 6 infections healed out of 8 and in the TRP group 1 out of 6.

Alanylglutamine reduces muscle loss of alanine and glutamine in post-operative anaesthetized dogs

1. The present study examined the effect of an infusion of the dipeptide alanylglutamine or of the corresponding amino acids alanine and glutamine in equimolar amounts (10 mumol min-1 kg-1) on the canine hindlimb exchange of alanine and glutamine in the post-operative anaesthetized dog. In contrast to glutamine, the dipeptide alanylglutamine is stable in aqueous solution and therefore would be a suitable substrate for parenteral nutrition. 2. The infusion of alanylglutamine increased (a) the arterial concentration of alanylglutamine to a plateau level (120 +/- 9.5 mumol/l, mean +/- SEM) 20 min after start of the infusion, (b) the mean arterial alanine concentration from 761 +/- 42 to a plateau of 1500-1700 mumol/l (P greater than 0.01) and (c) the arterial glutamine concentration from 407 +/- 51 to a plateau of 1050-1500 mumol/l (P greater than 0.01). Alanine and glutamine levels were slightly higher (14% and 26%, respectively, NS) in the group receiving the equimolar amount of alanine and glutamine. 3. Infusion of alanylglutamine for 1 h abolished the net efflux of glutamine (from -0.80 +/- 0.1 to -0.03 +/- 0.2 mumol min-1 kg-1; P greater than 0.05) and invoked a net influx of alanine (from -0.50 +/- 0.19 to +0.27 +/- 0.14 mumol min-1 kg-1; P greater than 0.01). These changes were similar to those achieved when the two amino acids were infused. 4. This study demonstrates that during short-term administration of alanylglutamine or of the corresponding amino acids the nitrogen release from the hindlimb of the anaesthetized post-operative dog via alanine and glutamine is reduced.

Aorto-Y-bifurcation graft: Dacron versus PTFE. Preliminary results of a randomized prospective study

A randomized prospective study comparing PTFE-Y and Dacron-Y-grafts with regard to function rate, morphology, hemodynamic differences along the proximal anastomosis and body of the graft, complications and quality of material was performed. Between March 1983 and February 1987, 112 patients were admitted to the study. Randomization including the criteria of age, sex, indication to operation (chronic occlusive disease, aneurysm) run-off, diabetes, nicotine consumption and operative approach (transperitoneal, retroextraperitoneal) followed the methods of adaptive randomization developed by Pocock and Simon and was well balanced. Function rate and complications as well as morphological alterations showed no significant differences in either group. During a mean observation period of 24 months, Group I yielded a 97% and Group II a 95% function rate (Kaplan-Meier). In all patients but one in each group with limb graft occlusions (n = 5) function was regained by successful thrombectomy and profundaplasty. With respect to Doppler ultrasound differences in flow pattern, in four patients with enlarged proximal side-end anastomosis and adequate--not to large--incision is recommended performing the proximal anastomosis.

Influence of leupeptin on protein and amino-acid metabolism in septic rats

We investigated the influence of leupeptin (LP) intraperitoneal injection (40 mumol/2 days) on protein and amino-acid metabolism of septic rats (cecal ligation). All septic rats lost weight (-17 +/- 4 g), which was not prevented by LP administration (-24 +/- 1.8 g, n.s.). LP injection evoked weight loss even in normal rats (p less than 0.05 vs controls). Weight loss was accompanied by enhanced urinary nitrogen losses in all three groups. LP reduced food intake for 47% in control rats. Cecal ligation, and also the administration of LP, led to alterations of amino-acid metabolism. The most important changes were found in muscle free amino-acid concentrations with highly decreased levels of free glutamine. A glutamine deficiency is known to be related to a decreased rate of protein synthesis. The proteolytic rate in incubated soleus muscle was increased for 11.5% and even higher in LP-treated septic rats (+22%). It is concluded that the administration of LP cannot reverse protein catabolism in sepsis--possibly because LP does not influence those enzymes or proteases involved in tissue loss, or LP is inactivated by enzymes in rat tissues.

[Measuring blood flow and catheterization technic in the acute and chronic dog model]

Metabolic studies under in vivo conditions may require a simultaneous catheterization of various organs. Because of phylogenetic relationships, pigs or dogs are best suitable for metabolic investigations. Organ-specific flow rates and substrate balances can be determined by means of dye dilution techniques (indocyanine green - ICG, para-aminohippuric acid - PAH, bromsulphthalein - BSP). An easy method for catheter insertion under anesthesiological and operative conditions is described.