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We conducted an analog sampling expedition under simulated mission constraints to areas dominated by basaltic tephra of the Eldfell and Fimmvörðuháls lava fields (Iceland). Sites were selected to be “homogeneous” at a coarse remote sensing resolution (10–100 m) in apparent color, morphology, moisture, and grain size, with best-effort realism in numbers of locations and replicates. Three different biomarker assays (counting of nucleic-acid-stained cells via fluorescent microscopy, a luciferin/luciferase assay for adenosine triphosphate, and quantitative polymerase chain reaction (qPCR) to detect DNA associated with bacteria, archaea, and fungi) were characterized at four nested spatial scales (1 m, 10 m, 100 m, and >1 km) by using five common metrics for sample site representativeness (sample mean variance, group F tests, pairwise t tests, and the distribution-free rank sum H and u tests). Correlations between all assays were characterized with Spearman's rank test. The bioluminescence assay showed the most variance across the sites, followed by qPCR for bacterial and archaeal DNA; these results could not be considered representative at the finest resolution tested (1 m). Cell concentration and fungal DNA also had significant local variation, but they were homogeneous over scales of >1 km. These results show that the selection of life detection assays and the number, distribution, and location of sampling sites in a low biomass environment with limited a priori characterization can yield both contrasting and complementary results, and that their interdependence must be given due consideration to maximize science return in future biomarker sampling expeditions. Key Words: Astrobiology—Biodiversity—Microbiology—Iceland—Planetary exploration—Mars mission simulation—Biomarker. Astrobiology 17, 1009–1021.

Field expeditions that simulate the operations of robotic planetary exploration missions at analog sites on Earth can help establish best practices and are therefore a positive contribution to the planetary exploration community. There are many sites in Iceland that possess heritage as planetary exploration analog locations and whose environmental extremes make them suitable for simulating scientific sampling and robotic operations. We conducted a planetary exploration analog mission at two recent lava fields in Iceland, Fimmvorðuhals (2010) and Eldfell (1973), using a specially developed field laboratory. We tested the utility of in-field site sampling down selection and tiered analysis operational capabilities with three life detection and characterization techniques: fluorescence microscopy (FM), adenine-triphosphate (ATP) bioluminescence assay, and quantitative polymerase chain reaction (qPCR) assay. The study made use of multiple cycles of sample collection at multiple distance scales and field laboratory analysis using the synchronous life-detection techniques to heuristically develop the continuing sampling and analysis strategy during the expedition. Here we report the operational lessons learned and provide brief summaries of scientific data. The full scientific data report will follow separately. We found that rapid in-field analysis to determine subsequent sampling decisions is operationally feasible, and that the chosen life detection and characterization techniques are suitable for a terrestrial life-detection field mission. In-field analysis enables the rapid obtainment of scientific data and thus facilitates the collection of the most scientifically relevant samples within a single field expedition, without the need for sample relocation to external laboratories. The operational lessons learned in this study could be applied to future terrestrial field expeditions employing other analytical techniques and to future robotic planetary exploration missions.

Objectives. To compare the effect of octreotide with placebo on symptoms, tumour marker and quality of life in patients with gastrointestinal neuroendocrine tumours and liver metastases. Design. A blinded, placebo-controlled, cross-over study was performed. The number of flushing epidodes and diarrhoea episodes were registered for 1 week prior to the study and for the 8-week duration of the study. Quality of life and 24-h urinary 5-hydroxyindoleacetic acid (5-HIAA) excretion were measured before the start, and at 4 and 8 weeks. Quality of life was registered with the Psychosocial Adjustment to Illness Scale (PAIS) and 5-HIAA measured by high-performance chromatography with electrochemical detection. 5-HIAA values exceeding 45 μmol 24 h−1 were considered to be elevated. Setting. The study was performed in a tertiary referral centre. Subjects. Twelve patients were approached; eleven patients were included, with a mean age of 56.5 (range 30–72) years. The primary tumour originated from the small intestine in nine and from the pancreas in two patients. The main symptoms were diarrhoea, flushing and nausea. The 24-h excretion of 5-HIAA was increased in all patients. Interventions. Patients were treated for 4 weeks with octreotide (100 μg) subcutaneously, twice daily, and for 4 weeks on placebo (octreotide vehicle) in random starting order. Main outcome measures. The main outcome measures were the number of episodes of the main clinical symptom(s) and 24-h 5-HIAA excretion. Results. Octreotide lowered diarrhoea and flushing frequency significantly compared to placebo. 5-HIAA excretion was reduced during treatment with the active drug. Two domains of the PAIS were significantly improved, indicating that the reduction of tumour marker and symptoms were clinically important. Conclusions. The clinical effect of octreotide on symptoms in patients with neuroendocrine tumours was demonstrated in a controlled, prospective trial.

The extent of heart disease and its relationship to the serotonin metabolite 5-hydroxyindoleacetic acid (5-HIAA), was studied with M-mode, 2D and Doppler echocardiography in 42 consecutive patients, 30 females and 12 males, median age 63 (range 23-75) years with histologically verified mid-gut tumour, liver metastases and 24-h urinary 5-HIAA excretion above 47 mumol.24 h-1. All patients had normal left ventricular ejection fractions, median 65% (interquartile range (IQR) 54-74%). Moderate to severe tricuspid regurgitation (TR) was diagnosed in 22 patients (59%); mitral or aortic regurgitation was found in nine (24%) and six (16%) patients, respectively. The mitral flow peak early (E) on late (A) velocity ratio was significantly decreased compared to age-matched normal subjects. The group of patients with 5-HIAA excretion exceeding 1000 mumol.24h-1 contained significantly more patients with severe TR than those with a lower excretion. The decrease in the E/A ratio may indicate reduced left ventricular compliance, possibly secondary to fibrous changes similar to those seen intra-abdominally and in the right side of the heart. As serotonin is degraded in the lung circulation, other mediators such as tachykinins and cytokines (PDGF) may be involved.

To assess their accuracies as markers for malignancy, we assayed alpha 2-macroglobulin, C1-inhibitor, alpha 1-protease inhibitor, and total proteins in ascites and plasma from patients with gastrointestinal cancer (n = 15) and non-malignant liver disease (n = 13), using functional and immunologic assays. For all inhibitors and total proteins determined in ascites, the values in the cancer group were significantly higher than the corresponding values in the group with non-malignant liver disease. The diagnostic accuracy for differentiating malignancy-related from non-malignant ascites was 93% for a alpha 1-protease inhibitor valueor = 50% of the pool plasma value and 90% for alpha 2-macroglobulinor = 16%, C1-inhibitoror = 40% (all functional assays), and total proteinsor = 20 g/l (biuret). In conclusion, functional assays for alpha 2-macroglobulin, C1-inhibitor, and alpha 1-protease inhibitor and determination of total proteins in ascites appeared to be very informative tests for the differential diagnosis of ascites. The test for alpha 1-protease inhibitor gave higher specificity (92% versus 77%) and likelihood ratio for a positive test (12 versus 4) compared with the other tests.

Carcinoid cell cultures were established from primary tumours and liver and mesenteric metastases. The cells continued to produce serotonin for up to 6 months. Cells from different tumours showed different properties. In most wells carcinoid cells grew on a layer of fibroblasts. The tendency to co-culture seemed to be less marked in cells from liver biopsy specimens. The amount of serotonin decreased to 63% 300 min after addition of the somatostatin analogue SMS 201-995 (SMS) to the culture, compared with controls (p0.05; n = 10). This decrease was observed up until 12 days, when SMS was added at each change of medium (p0.005; n = 8). In the first 10 min, however, SMS induced an increase in serotonin concentration (p0.005; n = 11). This effect may be related to other, immediate stimulatory effects of SMS seen in other cell lines originating from neural ridge-derived tissue. We believe it is important to elucidate the properties of individual tumours, as choice of therapy may vary between patients with the same diagnosis. We have described a method to obtain such information within a couple of days, before a definite treatment is selected.

In the period 1970 to 1987, 171 patients with small-intestinal mucosal atrophy have been hospitalized in our department. Of these, 132 patients fulfilled the diagnostic criteria of coeliac disease on the basis of histologic findings and clinical improvement on a gluten-free diet. Aspartate aminotransferase (ASAT), alanine aminotransferase (ALAT), and alkaline phosphatase (ALP) were chosen as markers of hepatic involvement. Elevation above the normal range in one or more of these tests was seen in 62 patients (47.0%, group I). In 70 patients (53.0%, group II) of similar age the levels of these variables were normal. In group I, 14 (10.6%) patients had an elevation of ALP only, leaving 48 (36.4%) patients with pathologic values for one or both transaminases. In group I, 32 patients had their ASAT, ALAT, and ALP reexamined after at least 6 months of gluten-free diet. Among the patients with increased values of one or both transaminases 18 patients were tested before and at least 6 months after start of gluten-free diet. The variables were significantly reduced in all patients. Liver biopsies were performed in 37 patients, and findings were normal in 5. In 25 patients the changes were classified as non-specific. Chronic active hepatitis was demonstrated in five patients. In one of these patients primary sclerosing cholangitis and ulcerative colitis were also diagnosed. Concomitant malignant disease was found in 22 patients, of whom 16 had malignant lymphoma. Malignant disease was seen more often in group I than group II (p less than 0.01). In conclusion, liver lesions were found in a great proportion of the patients with coeliac disease.(ABSTRACT TRUNCATED AT 250 WORDS)

In order to define the role of two-portal endoscopic carpal tunnel release, a prospective randomised study with an independent observer was performed to compare endoscopic and open surgery. Thirty-two hands in 29 patients, with symptoms, clinical signs and EMG changes consistent with idiopathic carpal tunnel syndrome were randomised to either endoscopic carpal tunnel release or open release. No significant difference in sick leave between the two groups could be found, being a mean of 17 days (range 0–31 days) with endoscopic surgery, and 19 days (range 0–42 days) with open conventional surgery. No differences in surgical results were found, but three patients in the endoscopic group suffered transient numbness on the radial side of the ring finger.

The intestinal reactivity to emotional experiences is poorly understood. We therefore compared healthy controls with nonpsychiatric irritable bowel syndrome (IBS) patients and IBS patients with comorbid phobic anxiety disorders with respect to rectal wall reactivity during exposure to everyday words with emotional content. We found that 70.3% of the subjects responded either with increased or decreased rectal tone during exposure to anger words, 75.0% when exposed to sadness words, and 76.6% when exposed to anxiety words. We also investigated event-related potentials in the brain to the same stimuli. We observed significant group differences in the frontal brain to sadness (P0.001) and anxiety (P = 0.013) distracter words, and threshold significant group difference to anger (P = 0.053) distracter words. Rectal wall reactivity during the word series significantly predicted frontal amplitude to the same word series, indicating a close interaction among mind, brain, and gut.

A 77 year-old man developed intermittent diarrhoea and malabsorption. Endoscopic findings and preliminary histological examination indicated ulcerative colitis. Special staining of biopsies from the duodenum and colon revealed amyloid deposits. Classification of the amyloid fibril protein verified AL-amyloidosis, and the diagnosis primary idiopathic amyloidosis was made. Amyloid deposit in the gastrointestinal tract are a common feature of primary and secondary amyloidosis. The symptoms and findings are nonspecific and resemble those of chronic inflammatory bowel disease and ischemic colitis. Secondary amyloidosis can be seen as a rare complication of Crohn's disease and ulcerative colitis. Special staining is necessary to show amyloid deposit, and the distinction between primary and secondary amyloidosis requires immunohistochemistry.

Food intolerance is frequently reported by patients and represent a diagnostic and therapeutic challenge. We review the nomenclature and report on symptoms, diagnostic tests and treatment. The nomenclature presented is based on the primary events such as toxic reactions, allergy or an undefined mechanism, including psychosomatic, although these subgroups may involve common pathogenetic mechanism. Double blind placebo controlled food challenge is the golden standard in the diagnostic workup and the importance of elimination diets--individually tailored to each patients requirements in cooperation with a nutritionist--is stressed. Through strict adherence to diagnostic and therapeutical guidelines, therapy may resolve food induced symptoms. Based on preliminary findings of signal transduction, we propose that symptoms in some patients may depend on an allergy type IV reaction. This working hypothesis forms the basis for further accumulation of knowledge of food intolerance reactions.

We describe a patient with moderate von Willebrand's disease who developed severe hyponatremia during prophylaxis with 1-deamino-8D-arginine vasopressin (desmopressin) to prevent bleeding in connection with surgery. This is a rare complication to desmopressin treatment in adults. Our present policy is to restrict administration of desmopressin to three 12-hourly infusions, to measure serum sodium before and during the treatment period, to determine body weight daily and to restrict administration of fluids.

We describe five patients with spontaneous bacterial peritonitis. The condition is reported more frequently than before and survival has improved. Important clinical features are increasing ascites and unexpected derangement of liver function. Possible predisposing factors, as well as diagnostic and therapeutic measures, are discussed. We emphasize the significance of ascitic polymorph nuclear cell count and bedside inoculation of ascites on blood culture medium, and stress the importance of prompt antibiotic therapy. The choice of empiric antimicrobial treatment is based on the reported frequency of causative agent and toxicity to drugs. Our experience so far indicates that cefotaxime administered as monotherapy is safe and efficient in these patients. Aminoglycosides should be avoided because of increased nephrotoxicity in patients with liver failure.

Toxic shock syndrome is a generalized disease traditionally thought to be caused by toxinproducing strains of Staphylococcus aurus. The syndrome is characterized by fever, hypotension, erythema of the skin, erythematous desquamation and multiple organ involvement. We present a case where the causative agent was most probably streptococci, thus demonstrating that the syndrome probably has a heterogeneous, toxin-related etiology.