Consensus and controversies regarding follow-up after treatment with curative intent of nonmetastatic colorectal cancer: a synopsis of guidelines used in countries represented in the European Society of Coloproctology.

AIM: It is common clinical practice to follow patients for a period of years after treatment with curative intent of nonmetastatic colorectal cancer, but follow-up strategies vary widely. The aim of this systematic review was to provide an overview of recommendations on this topic in guidelines from member countries of the European Society of Coloproctology, with supporting evidence. METHOD: A systematic search of Medline, Embase and the guideline databases Trip database, BMJ Best Practice and Guidelines International Network was performed. Quality assessment included use of the AGREE-II tool. All topics with recommendations from included guidelines were identified and categorized. For each subtopic, a conclusion was made followed by the degree of consensus and the highest level of evidence. RESULTS: Twenty-one guidelines were included. The majority recommended that structured follow-up should be offered, except for patients in whom treatment of recurrence would be inappropriate. It was generally agreed that clinical visits, measurement of carcinoembryoinc antigen and liver imaging should be part of follow-up, based on a high level of evidence, although the frequency is controversial. There was also consensus on imaging of the chest and pelvis in rectal cancer, as well as endoscopy, based on lower levels of evidence and with a level of intensity that was contradictory. CONCLUSION: In available guidelines, multimodal follow-up after treatment with curative intent of colorectal cancer is widely recommended, but the exact content and intensity are highly controversial. International agreement on the optimal follow-up schedule is unlikely to be achieved on current evidence, and further research should refocus on individualized 'patient-driven' follow-up and new biomarkers.

Maternal and foetal outcomes in pregnant systemic lupus erythematosus patients: an incident cohort from a stable referral population followed during 1990-2010.

OBJECTIVES: To assess the impact of systemic lupus erythematosus (SLE) on pregnancy outcome in a cohort of incident pregnant lupus patients referred to a Danish university hospital during 1990-2010. METHOD: All pregnant lupus patients were referred to the university hospital from a stable referral area with approximately 1.4 million inhabitants. Eighty-four pregnancies in 39 women were registered using the Danish National Registry and retrospective reviewing of medical records, laboratory results, and midwifery records from the Department of Rheumatology, the Department of Obstetrics and Gynaecology, and possible other departments. Data were compared to 29 059 births during 2005-2010, covering all births from the referral area. RESULTS: The 84 SLE pregnancies resulted in 62 live births. SLE flares developed in 46.4%, pre-eclampsia in 8.3%, and HELLP syndrome in 4.8% of cases. Significantly higher rates of premature delivery (p=0.0032), caesarean section (p=0.015), hypertension (p=0.025), and intrauterine growth retardation (IUGR) (p=0.003) were found. Disease activity significantly (p=0.021) increased the risk of prematurity threefold. Antiphospholipid antibody (aPL) presence significantly (p=0.002) increased the risk of spontaneous abortion threefold. Two babies died after extreme preterm birth. Two had neonatal lupus syndrome (NLS) and one had congenital heart block (CHB). Birth weight and length were significantly lower in the SLE cohort. An unexpectedly high number of cardiac septum defects (9.7%) were observed. CONCLUSIONS: From a stable referral area, an incident cohort of SLE pregnancies were mostly successful, but maternal and foetal complications were observed in one-half and one-third of cases, respectively. Outcome risk factors were identified. A possible new observation is a high frequency of cardiac septum defects.

Impact of arbuscular mycorrhizal fungi on uranium accumulation by plants.

Contamination by uranium (U) occurs principally at U mining and processing sites. Uranium can have tremendous environmental consequences, as it is highly toxic to a broad range of organisms and can be dispersed in both terrestrial and aquatic environments. Remediation strategies of U-contaminated soils have included physical and chemical procedures, which may be beneficial, but are costly and can lead to further environmental damage. Phytoremediation has been proposed as a promising alternative, which relies on the capacity of plants and their associated microorganisms to stabilize or extract contaminants from soils. In this paper, we review the role of a group of plant symbiotic fungi, i.e. arbuscular mycorrhizal fungi, which constitute an essential link between the soil and the roots. These fungi participate in U immobilization in soils and within plant roots and they can reduce root-to-shoot translocation of U. However, there is a need to evaluate these observations in terms of their importance for phytostabilization strategies.

Role and influence of mycorrhizal fungi on radiocesium accumulation by plants.

This review summarizes current knowledge on the contribution of mycorrhizal fungi to radiocesium immobilization and plant accumulation. These root symbionts develop extended hyphae in soils and readily contribute to the soil-to-plant transfer of some nutrients. Available data show that ecto-mycorrhizal (ECM) fungi can accumulate high concentration of radiocesium in their extraradical phase while radiocesium uptake and accumulation by arbuscular mycorrhizal (AM) fungi is limited. Yet, both ECM and AM fungi can transport radiocesium to their host plants, but this transport is low. In addition, mycorrhizal fungi could thus either store radiocesium in their intraradical phase or limit its root-to-shoot translocation. The review discusses the impact of soil characteristics, and fungal and plant transporters on radiocesium uptake and accumulation in plants, as well as the potential role of mycorrhizal fungi in phytoremediation strategies.

Suppression of the biocontrol agent trichoderma harzianum by mycelium of the arbuscular mycorrhizal fungus glomus intraradices in root-free soil

Trichoderma harzianum is an effective biocontrol agent against several fungal soilborne plant pathogens. However, possible adverse effects of this fungus on arbuscular mycorrhizal fungi might be a drawback in its use in plant protection. The objective of the present work was to examine the interaction between Glomus intraradices and T. harzianum in soil. The use of a compartmented growth system with root-free soil compartments enabled us to study fungal interactions without the interfering effects of roots. Growth of the fungi was monitored by measuring hyphal length and population densities, while specific fatty acid signatures were used as indicators of living fungal biomass. Hyphal 33P transport and beta-glucuronidase (GUS) activity were used to monitor activity of G. intraradices and a GUS-transformed strain of T. harzianum, respectively. As growth and metabolism of T. harzianum are requirements for antagonism, the impact of wheat bran, added as an organic nutrient source for T. harzianum, was investigated. The presence of T. harzianum in root-free soil reduced root colonization by G. intraradices. The external hyphal length density of G. intraradices was reduced by the presence of T. harzianum in combination with wheat bran, but the living hyphal biomass, measured as the content of a membrane fatty acid, was not reduced. Hyphal 33P transport by G. intraradices also was not affected by T. harzianum. This suggests that T. harzianum exploited the dead mycelium but not the living biomass of G. intraradices. The presence of external mycelium of G. intraradices suppressed T. harzianum population development and GUS activity. Stimulation of the hyphal biomass of G. intraradices by organic amendment suggests that nutrient competition is a likely means of interaction. In conclusion, it seemed that growth of and phosphorus uptake by the external mycelium of G. intraradices were not affected by the antagonistic fungus T. harzianum; in contrast, T. harzianum was adversely affected by G. intraradices.

Characterization of the HLA-A polymorphism by locus-specific polymerase chain reaction amplification and oligonucleotide hybridization.

This report describes a PCR-based typing protocol for the HLA-A polymorphism. Locus-specific primers selectively amplified HLA-A sequences from exon 1 to exon 3 in a single PCR that avoided co-amplification of other classical and nonclassical class I genes. The allelic variation in exons 2 and 3 of the HLA-A gene was examined with a set of 44 oligonucleotide probes. According to the recognized HLA-A sequences the protocol is potentially able to distinguish all known HLA-A alleles with unique nucleotide sequences in this gene region. The related HLA-A genotypes can also be identified in both homozygous and heterozygous individuals. Thus the protocol provides the highest resolution for HLA-A typing. The PCR-SSO typing technique is accurate, reliable, and particularly suitable for a large number of samples. The DNA typing results from 42 Tenth IHWS B-cell lines are compatible with the serologic and IEF definitions. Sixty-six unrelated donors from a northern Chinese population were also tested, with 16 HLA-A alleles detected. Four subtypes of HLA-A2 were found in this population. The distribution of HLA-A subtypes in the population indicated that 40% of donor-recipient pairs thought to be matched for HLA-A by serology would be mismatched. Two novel HLA-A alleles were identified by unusual oligonucleotide hybridization patterns.

VESICULAR-ARBUSCULAR MYCORRHIZA IN FIELD-GROWN CROPS: III. MYCORRHIZAL INFECTION AND RATES OF PHOSPHORUS INFLOW IN PEA PLANTS.

The importance of vesicular-arbuscular mycorrhiza (VAM) and P fertilizer for P nutrition and dry matter production in field peas (Pisum sativum L.) was studied in moderately P-deficient soil. Half of the experimental plots were fumigated to reduce the level of VAM infection. Shoots and 0 to 30 cm soil cores were sampled on three occasions. An extensive VAM infection was rapidly established in untreated soil, whereas infection levels were low in fumigated soil. Root growth responded to fumigation by increased root length and decreased root diameter. Fumigation reduced the P content in shoots considerably, and correspondingly the mean rates of P inflow per unit root length were 60% lower in fumigated than in untreated soil during flowering. These effects of fumigation were ascribed to the low levels of VAM infection in fumigated soil. The production of dry matter was not decreased accordingly in fumigated plots, although both it and P uptake were increased by adding P fertilizer. The possible reasons for this discrepancy are discussed. A supplementary survey on infection development at five other field sites showed that peas are extensively colonized by VAM fungi, even in soils where a standard procedure is being used. These results indicate that VAM is of major importance to P uptake by the field-grown pea.

Hyphal transport of 15 N-labelled nitrogen by a vesicular-arbuscular mycorrhizal fungus and its effect on depletion of inorganic soil N.

Hyphal transport of nitrogen from a 15 N-labelled ammonium source by a VA-mycorrhizal fungus was studied under controlled experimental conditions. Cucumis sativus L. cv. Aminex (F1 hybrid) was grown alone or together with Glomus intraradices Schenck and Smith in containers with a hyphal compartment separated from the rooting medium by a fine nylon mesh. Lateral movement of the applied 15 N towards the roots was minimized by using a nitrification inhibitor (N-serve) and a hyphal buffer compartment. Recovery of 15 N by mycorrhizal and non-mycorrhizal plants was 6 and 0%, respectively, after a labelling period of 23 days. The corresponding figures, without N-serve added, were 4 and 7%. A prolongation of the labelling period by 8 days (N-serve applied) resulted in an increase in the 15 N recovery by mycorrhizal plants to 30% of the applied 15 N. Non-mycorrhizal plants contained only traces of 15 N. The external hyphae depleted the soil in the hyphal compartment efficiently for inorganic N. In contrast, hyphal compartments of control containers still contained considerable amounts of inorganic N. The 15 N assimilated by the external hyphae in one hyphal compartment was not translocated in significant amounts to the external hyphae in another hyphal compartment. The possible implication of this for inter-plant N transfer by VA hyphal connections is discussed.

Benomyl inhibits phosphorus transport but not fungal alkaline phosphatase activity in a Glomus-cucumber symbiosis.

Short-term effects of benomyl on the arbuscular mycorrhizal fungus Glomus caledonium (Nicol. & Gerd.) Trappe and Gerdeman associated with Cucumis sativus L. were studied by measuring effects on fungal P transport and on fungal alkaline phosphatase activity. Mycorrhizal plants were grown in three compartment systems where nylon mesh was used to separate n root-free hyphal compartment (HC) and a root + hyphal compartment(RHC) from The main root compartment (RC). Non-mycorrhizal control plants were grown in similar growth units. After 6 wk benomyl was applied to the plants in three ways: as soil drenches to RHC or HC, or as u spray to the leaves. Benomyl was added in three concentrations. Equal amounts of 32 P and 33 P were added to the HC and to the RHC respectively, immediately after the application of benomyl. Plants were harvested 4-6 d later. Hyphal transport of 32 P from the HC was inhibited when benomyl was applied to the HC at 10 µg g-1 soil, whereas the uptake of 32 P from RHC I roots + hyphae) was reduced only at the highest dose of application to the RHC (100 µ g g-1 soil). In contrast to the marked reduction of benomyl on fungal P transport, the activity of fungal alkaline phosphatase inside the roots was unaffected by benomyl.

Phosphate transport by communities of arbuscular mycorrhizal fungi in intact soil cores.

• Variation in phosphate uptake capacity is reported here for natural communities of arbuscular mycorrhizal fungi associated with annual pasture plants. • Tests were made of methodology for quantifying phosphate uptake by hyphae associated with clover in soil cores from pastures containing different morphotypes of the fungi. This provided a direct measure of the phosphate uptake capacity of hyphae from 32 P-labelled soil in a root-free mesh bag inserted into the centre of intact soil cores. • Bicarbonate-extractable phosphorus in the soils ranged from very deficient to close to adequate for plant growth. Uptake of 32 P was related to an estimate of the length of hyphae formed in four of the five soils, but not to either the length or the proportion of roots colonized. In the fifth soil type, phosphate uptake by hyphae was negligible. • Phosphate uptake by natural communities of arbuscular mycorrhizal fungi in intact soil cores can be assessed directly, and is shown to be highly variable. The experimental approach could be applied widely for field investigations of phosphate uptake by hyphal networks.

Phospho-imaging as a tool for visualization and noninvasive measurement of P transport dynamics in arbuscular mycorrhizas.

• A new method is described for monitoring hyphal 32 P transport in compartmented, monoxenic mycorrhizal root cultures. Nondestructive time-course measurements of P transport in hyphae were obtained by capturing digital autoradiograms on P-imaging screens, and comparing with growth observed by optical scanning. 32 P distribution measured by densitometry on the day of harvest closely agreed with values obtained by liquid scintillation counting after destructive harvest. • Virtually all labeled PO4 was absorbed by arbuscular mycorrhizal (AM) hyphae, but transfer to the roots appeared to be incomplete. P transport was not unidirectional towards the roots, as 32 P was also transported from the root compartment to the hyphal compartment. Net P flux rates were calculated for hyphae crossing between compartments, taking bidirectional flow into account. • Amounts of transported P were poorly correlated with extra-radical hyphal length and root d. wt, but highly correlated with the number of hyphae crossing the barrier separating the two compartments. Such correlations were highest when only hyphae with detectable protoplasmic streaming were considered. • The method was tested using radiolabeled P sources, H2 PO4 - and cytidine triphosphate (CTP), and the AM fungi, Glomus intraradices and G. proliferum. Fungal transport of 32 P from CTP was much slower than from PO4 for both fungi.

MRI of human tumor xenografts in vivo: proton relaxation times and extracellular tumor volume.

Proton T1 and T2 differ substantially between tumors, but the tumor properties causing heterogeneity in T1 and T2 have not been fully recognized. The purpose of the study reported here was to investigate whether differences in T1 and T2 between tumors are mainly a consequence of differences in the fractional volume of the extracellular compartment. The study was performed using a single human tumor xenograft line showing large naturally occurring intratumor heterogeneity in the size of the extracellular compartment. The size of the extracellular compartment was calculated from the volume and the density of the tumor cells. Cell volume was measured by an electronic particle counter. Cell density was determined by stereological analysis of histological preparations. T1 and T2 were measured by MRI in vivo both in the absence and presence of Gd-DTPA. Two spin-echo pulse sequences were used, one with a repetition time (TR) of 600 ms and echo times (TEs) of 20, 40, 60, and 80 ms and the other with a TR of 2,000 ms and TEs of 20, 40, 60, and 80 ms. Measurements of T1 and T2 in the presence of Gd-DTPA were performed in a state of semi-equilibrium between uptake and clearance of Gd-DTPA. MR-images and histological preparations of tumor subregions homogeneous in extracellular volume were analysed in pairs. The extracellular volume differed between tumor subregions from 5 to 70%. T1 and T2 measured in the absence of Gd-DTPA differed between tumor subregions by a factor of approximately 1.5 and increased with increasing extracellular volume. The relative decrease in T1 caused by Gd-DTPA, represented by (T1 control-T1 Gd-DTPA)/T1 control, also increased with increasing extracellular volume.(ABSTRACT TRUNCATED AT 250 WORDS)

A program for calculating and displaying compatibility matrices as an aid in determining reticulate evolution in molecular sequences.

Reticulate evolution in molecular sequences is caused by recombination or gene conversion, and may interfere with the reconstruction of evolutionary history. This paper presents a program which calculates compatibility matrices for detecting reticulate evolution. In addition to visual inspection of matrices, they can be analysed statistically for clustering. The method is demonstrated using human and chimpanzee gamma-globin sequences.

Detection of necrosis in human tumour xenografts by proton magnetic resonance imaging.

Tumours with necrotic regions have an inadequate blood supply and are expected to differ from well-vascularised tumours in response to treatment. The purpose of the present work was to investigate whether proton magnetic resonance imaging (MRI) might be used to detect necrotic regions in tumours. MR images and histological sections from individual tumours of three different amelanotic human melanoma xenograft lines (BEX-t, HUX-t, SAX-t) were analysed in pairs. MRI was performed at 1.5 T using two spin-echo pulse sequences, one with a repetition time (TR) of 600 ms and echo times (TEs) of 20, 40, 60 and 80 ms and the other with a TR of 2000 ms and TEs of 20, 40, 60 and 80 ms. Spin-lattice relaxation time (T1), spin-spin relaxation time (T2) and proton density (N0) were calculated for each volume element corresponding to a pixel. Synthetic MR images, pure T1, T2 and N0 images and spin-echo images with chosen values for TR and TE were generated from these data. T1, T2 and N0 distributions of tumour subregions, corresponding to necrotic regions and regions of viable tissue as defined by histological criteria, were also generated. T1 and T2 were significantly shorter in the necrotic regions than in the regions of viable tissue in all tumours. These differences were sufficiently large to allow the generation of synthetic spin-echo images showing clear contrast between necrosis and viable tissue. Maximum contrast was achieved with TRs within the range 2800-4000 ms and TEs within the range 160-200 ms. Necrotic tissue could also be distinguished from viable tissue in pure T1 and T2 images. Consequently, the possibility exists that MRI might be used for detection of necrotic regions in tumours and hence for prediction of tumour treatment response.

Soft-tissue procedures for the exposed knee arthroplasty. 18 cases followed for 7 (1-17) years.

Reconstructive surgery was performed in 18 knee arthroplasties because of wound-healing problems or skin necrosis. The procedure, after debridement, included myocutaneous, muscle flap, and split-skin grafts. Revision was necessary in 6 cases. After 1-17 years, 6 patients had died, 2 had had a low femur amputation, and 5 had had an arthrodesis. Five patients had retained the prosthesis, although 3 of them had considerable pain and poor mobility; only 2 patients were tolerably painfree and had acceptable mobility. Patients with an exposed knee endoprosthesis should be referred to centers with special competence in plastic reconstructive surgery.

The partition matrix: exploring variable phylogenetic signals along nucleotide sequence alignments.

The partition matrix is a graphical tool for comparative analysis of nucleotide sequences following alignment. It is particularly useful for investigating the divergent phylogenies of sequence regions undergoing reticulate evolution. A partition matrix is generated by determining the consistency of the parsimoniously informative sites in a set of aligned sequences with the binary partitions inferred from the sequences. Since the linear order of sites is maintained, the matrix can be used to assess whether the distribution of sites either supporting or conflicting with particular partitions changes along the length of the alignment. The usefulness of the matrix in allowing visual identification of differences in evolutionary history among regions depends on the order in which partitions are shown; several suitable ordering schemes are proposed. We demonstrate the use of the partition matrix in interpreting the evolution of the pseudoautosomal boundary region on the sex chromosome of catarrhine primates. Its routine use should help to avoid attempts to derive single phylogenies from sequences whose evolution has been reticulate and to identify the gene conversion or recombination events underlying the reticulation. The method is relatively fast. It is exploratory, and it can form the basis for more formal analysis, which we discuss.

Patterns of reticulate evolution for the classical class I and II HLA loci.

Some alleles of the major histocompatibility complex (MHC) genes have a reticulate pattern of evolution, probably resulting from the exchange of segments by gene conversion or recombination. Here we compare the extent and patterns of reticulate evolution among the classical class I and class II loci of the human MHC using the recently developed compatibility and partition matrix methods. A complex pattern is revealed with substantial differences among loci in the extent and pattern of reticulation. Extremely high levels of reticulation are observed at HLA-B and HLA-DPB1, high levels at HLA-A and HLA-DRB1, moderate levels at HLA-C and HLA-DQB1, and low levels at HLA-DQA1. The reticulate events are concentrated in the exons encoding the highly variable, peptide-binding domains, suggesting that the sequence combinations produced by these events are maintained by natural selection.

Correlating sequence variation with HLA-A allelic families: implications for T cell receptor binding specificities.

Six families of HLA-A alleles have been previously proposed on the basis of nucleotide sequence and phylogenetic analysis. Here, sequence polymorphism has been examined at both the protein and DNA levels in a family specific manner and new minimal signatures for each of the families have been delineated. The DNA and protein sites that constitute these signatures are distributed throughout the length of the sequence and generally do not appear to act to promote structural or functional features of the molecules. This is explained by the fact that traditional signatures suffer biases where, for example, recombination products of low frequency can obscure one family's trend by introducing 'impurities' intrinsic to another family. In the absence of complete frequency data, a closer approximation of family signatures can be defined by sites that show strong correlation with the family groups. Using this description, the amino acid positions 62, 97 and 114, localized in the antigen-binding cleft are, in combination, sufficient to discriminate between the six families. Thus, while the composition of the whole cleft defines the details of antigen specificity, these sites in particular, play a key role in modulating supertype peptide specificity and T cell recognition.

Phosphorus effects on the mycelium and storage structures of an arbuscular mycorrhizal fungus as studied in the soil and roots by analysis of Fatty Acid signatures.

The distribution of an arbuscular mycorrhizal (AM) fungus between soil and roots, and between mycelial and storage structures, was studied by use of the fatty acid signature 16:1(omega)5. Increasing the soil phosphorus level resulted in a decrease in the level of the fatty acid 16:1(omega)5 in the soil and roots. A similar decrease was detected by microscopic measurements of root colonization and of the length of AM fungal hyphae in the soil. The fatty acid 16:1(omega)5 was estimated from two types of lipids, phospholipids and neutral lipids, which mainly represent membrane lipids and storage lipids, respectively. The numbers of spores of the AM fungus formed in the soil correlated most closely with neutral lipid fatty acid 16:1(omega)5, whereas the hyphal length in the soil correlated most closely with phospholipid fatty acid 16:1(omega)5. The fungal neutral lipid/phospholipid ratio in the extraradical mycelium was positively correlated with the level of root infection and thus decreased with increasing applications of P. The neutral lipid/phospholipid ratio indicated that at high P levels, less carbon was allocated to storage structures. At all levels of P applied, the major part of the AM fungus was found to be present outside the roots, as estimated from phospholipid fatty acid 16:1(omega)5. The ratio of extraradical biomass/intraradical biomass was not affected by the application of P, except for a decrease at the highest level of P applied.