MiDaf16-like and MiSkn1-like gene families are reliable targets to develop biotechnological tools for the control and management of Meloidogyne incognita

Meloidogyne incognita is a plant-parasitic root-knot nematode (RKN, PPN) responsible for causing damage to several crops worldwide. In Caenorhabditis elegans, the DAF-16 and SKN-1 transcription factors (TFs) orchestrate aging, longevity, and defense responses to several stresses. Here, we report that MiDaf16-like1 and MiSkn1-like1, which are orthologous to DAF-16 and SKN-1 in C. elegans, and some of their targets, are modulated in M. incognita J2 during oxidative stress or plant parasitism. We used RNAi technology for the stable production of siRNAs in planta to downregulate the MiDaf16-like1 and MiSkn1-like1 genes of M. incognita during host plant parasitism. Arabidopsis thaliana and Nicotiana tabacum overexpressing a hairpin-derived dsRNA targeting these genes individually (single-gene silencing) or simultaneously (double-gene silencing) were generated. T2 plants were challenged with M. incognita and the number of eggs, galls, and J2, and the nematode reproduction factor (NRF) were evaluated. Our data indicate that MiDaf16-like1, MiSkn1-like1 and some genes from their networks are modulated in M. incognita J2 during oxidative stress or plant parasitism. Transgenic A. thaliana and N. tabacum plants with single- or double-gene silencing showed significant reductions in the numbers of eggs, J2, and galls, and in NRF. Additionally, the double-gene silencing plants had the highest resistance level. Gene expression assays confirmed the downregulation of the MiDaf16-like1 and MiSkn1-like1 TFs and defense genes in their networks during nematode parasitism in the transgenic plants. All these findings demonstrate that these two TFs are potential targets for the development of biotechnological tools for nematode control and management in economically important crops.

The lipid metabolism in thraustochytrids

Thraustochytrids are unicellular heterotrophic marine protists of the Stramenopile group, often considered as non-photosynthetic microalgae. They have been isolated from a wide range of habitats including deep sea, but are mostly present in waters rich in sediments and organic materials. They are abundant in mangrove forests where they are major colonizers, feeding on decaying leaves and initiating the mangrove food web. Discovered 80 years ago, they have recently attracted considerable attention due to their biotechnological potential. This interest arises from their fast growth, their specific lipid metabolism and the improvement of the genetic tools and transformation techniques. These organisms are particularly rich in ω3-docosahexaenoic acid (DHA), an 'essential' fatty acid poorly encountered in land plants and animals but required for human health. To produce their DHA, thraustochytrids use a sophisticated system different from the classical fatty acid synthase system. They are also a potential source of squalene and carotenoids. Here we review our current knowledge about the life cycle, ecophysiology, and metabolism of these organisms, with a particular focus on lipid dynamics. We describe the different pathways involved in lipid and fatty acid syntheses, emphasizing their specificity, and we report on the recent efforts aimed to engineer their lipid metabolism.

Improved drought stress tolerance in Arabidopsis by CRISPR/dCas9 fusion with a Histone AcetylTransferase

Drought episodes decrease plant growth and productivity, which in turn cause high economic losses. Plants naturally sense and respond to water stress by activating specific signalling pathways leading to physiological and developmental adaptations. Genetically engineering genes that belong to these pathways might improve the drought tolerance of plants. The abscisic acid (ABA)-responsive element binding protein 1/ABRE binding factor (AREB1/ABF2) is a key positive regulator of the drought stress response. We investigated whether the CRISPR activation (CRISPRa) system that targets AREB1 might contribute to improve drought stress tolerance in Arabidopsis. Arabidopsis histone acetyltransferase 1 (AtHAT1) promotes gene expression activation by switching chromatin to a relaxed state. Stable transgenic plants expressing chimeric dCas9^HAT were first generated. Then, we showed that the CRISPRa dCas9^HAT mechanism increased the promoter activity controlling the β-glucuronidase (GUS) reporter gene. To activate the endogenous promoter of AREB1, the CRISPRa dCas9^HAT system was set up, and resultant plants showed a dwarf phenotype. Our qRT-PCR experiments indicated that both AREB1 and RD29A, a gene positively regulated by AREB1, exhibited higher gene expression than the control plants. The plants generated here showed higher chlorophyll content and faster stomatal aperture under water deficit, in addition to a better survival rate after drought stress. Altogether, we report that CRISPRa dCas9^HAT is a valuable biotechnological tool to improve drought stress tolerance through the positive regulation of AREB1.

Interdependency of efficient nodulation and arbuscular mycorrhization in Piptadenia gonoacantha, a Brazilian legume tree

Tripartite interactions between legumes and their root symbionts (rhizobia and arbuscular mycorrhizal fungi, AMF) are poorly understood, although it is well established that only specific combinations of symbionts lead to optimal plant growth. A classic example in which to investigate such interactions is the Brazilian legume tree Piptadenia gonoacantha (Caesalpinioideae), for which efficient nodulation has been described as dependent on the presence of AMF symbiosis. In this study, we compared the nodulation behaviour of several rhizobial strains with or without AMF inoculation, and performed analyses on nodulation, nodule cytology, N-fixing efficiency, and plant growth response. Nodulation of P. gonoacantha does not rely on the presence of AMF, but mycorrhization was rhizobial strain-dependent, and nodule effectiveness and plant growth were dependent on the presence of specific combinations of rhizobial strains and AMF. The co-occurrence of both symbionts within efficient nodules and the differentiation of bacteroids within nodule cells were also demonstrated. Novel close interactions and interdependency for the establishment and/or functioning of these symbioses were also revealed in Piptadenia, thanks to immunocytochemical analyses. These data are discussed in terms of the evolutionary position of the newly circumscribed mimosoid clade within the Caesalpinioid subfamily and its relative proximity to non-nodulated (but AMF-associated) basal subfamilies.

Meloidogyne incognita PASSE-MURAILLE (MiPM) Gene Encodes a Cell-Penetrating Protein That Interacts With the CSN5 Subunit of the COP9 Signalosome

The pathogenicity of phytonematodes relies on secreted virulence factors to rewire host cellular pathways for the benefits of the nematode. In the root-knot nematode (RKN) Meloidogyne incognita, thousands of predicted secreted proteins have been identified and are expected to interact with host proteins at different developmental stages of the parasite. Identifying the host targets will provide compelling evidence about the biological significance and molecular function of the predicted proteins. Here, we have focused on the hub protein CSN5, the fifth subunit of the pleiotropic and eukaryotic conserved COP9 signalosome (CSN), which is a regulatory component of the ubiquitin/proteasome system. We used affinity purification-mass spectrometry (AP-MS) to generate the interaction network of CSN5 in M. incognita-infected roots. We identified the complete CSN complex and other known CSN5 interaction partners in addition to unknown plant and M. incognita proteins. Among these, we described M. incognita PASSE-MURAILLE (MiPM), a small pioneer protein predicted to contain a secretory peptide that is up-regulated mostly in the J2 parasitic stage. We confirmed the CSN5-MiPM interaction, which occurs in the nucleus, by bimolecular fluorescence complementation (BiFC). Using MiPM as bait, a GST pull-down assay coupled with MS revealed some common protein partners between CSN5 and MiPM. We further showed by in silico and microscopic analyses that the recombinant purified MiPM protein enters the cells of Arabidopsis root tips in a non-infectious context. In further detail, the supercharged N-terminal tail of MiPM (NTT-MiPM) triggers an unknown host endocytosis pathway to penetrate the cell. The functional meaning of the CSN5-MiPM interaction in the M. incognita parasitism is discussed. Moreover, we propose that the cell-penetrating properties of some M. incognita secreted proteins might be a non-negligible mechanism for cell uptake, especially during the steps preceding the sedentary parasitic phase.

Genetic diversity of symbiotic Paraburkholderia species isolated from nodules of Mimosa pudica (L.) and Phaseolus vulgaris (L.) grown in soils of the Brazilian Atlantic Forest (Mata Atlântica)

Some species of the genus Paraburkholderia that are able to nodulate and fix nitrogen in symbiosis with legumes are called β-rhizobia and represent a group of ecological and biotechnological importance. We used Mimosa pudica and Phaseolus vulgaris to trap 427 rhizobial isolates from rhizospheric soil of Mimoseae trees in the Brazilian Atlantic Forest. Eighty-four representative strains were selected according to the 16S rRNA haplotypes and taxonomically characterized using a concatenated 16S rRNA-recA phylogeny. Most strains were assembled in the genus Paraburkholderia, including Paraburkholderia sabiae and Pa. nodosa. Mesorhizobium (α-rhizobia) and Cupriavidus (β-rhizobia) were also isolated, but in smaller proportions. Multilocus sequence analysis and BOX-PCR analyses indicated that six clusters of Paraburkholderia represent potential new species. In the phylogenetic analysis of the nodC gene, the majority of the strains were positioned in the same groups as in the 16S rRNA-recA tree, indicative of stability and vertical inheritance, but we also identified horizontal transfer of nodC in Pa. sabiae. All α- and β-rhizobial species were trapped by both legumes, although preferences of the host plants for specific rhizobial species have been observed.

Does early response to intravenous glucocorticoids predict the final outcome in patients with moderate-to-severe and active Graves' orbitopathy?

PURPOSE

Intravenous glucocorticoids (ivGCs) given as 12-weekly infusions are the first-line treatment for moderate-to-severe and active Graves' orbitopathy (GO), but they are not always effective. In this study, we evaluated whether response at 6 weeks correlated with outcomes at 12 (end of intervention) and 24 (follow-up) weeks, particularly in patients initially unresponsive.

METHODS

Our database (Bartalena et al. J Clin Endocrinol Metab 97:4454-4463, 10), comprising 159 patients given three different cumulative doses of methylprednisolone (2.25, 4.98, 7.47 g) was analyzed, pooling data for analyses. Responses at 6 weeks were compared with those at 12 and 24 weeks using three outcomes: overall ophthalmic involvement [composite index (CI)]; quality of life (QoL); Clinical Activity Score (CAS). Responses were classified as "Improved", "Unchanged", "Deteriorated", compared to baseline.

RESULTS

Deteriorated patients at 6 weeks for CI (n = 8) remained in the same category at 12 weeks and 7/8 at 24 weeks. Improved patients at 6 weeks for CI (n = 51) remained in the same category in 63% and 53% of cases at 12 and 24 weeks, respectively. Unchanged patients at 6 weeks (n = 100) eventually improved in 28% of cases (CI), 58% (CAS), 32% (QoL). There was no glucocorticoid dose-dependent difference in the influence of early response on later outcomes.

CONCLUSIONS

Patients who deteriorate at 6 weeks after ivGCs are unlikely to benefit from continuing ivGCs. Patients unresponsive at 6 weeks still have a significant possibility of improvement later. Accordingly, they may continue ivGC treatment, or, alternatively, possibly stop ivGCs and be switched to a second-line treatment.

Plant-parasitic nematodes: towards understanding molecular players in stress responses

BACKGROUND

Plant-parasitic nematode interactions occur within a vast molecular plant immunity network. Following initial contact with the host plant roots, plant-parasitic nematodes (PPNs) activate basal immune responses. Defence priming involves the release in the apoplast of toxic molecules derived from reactive species or secondary metabolism. In turn, PPNs must overcome the poisonous and stressful environment at the plant-nematode interface. The ability of PPNs to escape this first line of plant immunity is crucial and will determine its virulence.

SCOPE

Nematodes trigger crucial regulatory cytoprotective mechanisms, including antioxidant and detoxification pathways. Knowledge of the upstream regulatory components that contribute to both of these pathways in PPNs remains elusive. In this review, we discuss how PPNs probably orchestrate cytoprotection to resist plant immune responses, postulating that it may be derived from ancient molecular mechanisms. The review focuses on two transcription factors, DAF-16 and SKN-1 , which are conserved in the animal kingdom and are central regulators of cell homeostasis and immune function. Both regulate the unfolding protein response and the antioxidant and detoxification pathways. DAF-16 and SKN-1 target a broad spectrum of Caenorhabditis elegans genes coding for numerous protein families present in the secretome of PPNs. Moreover, some regulatory elements of DAF-16 and SKN-1 from C. elegans have already been identified as important genes for PPN infection.

CONCLUSION

DAF-16 and SKN-1 genes may play a pivotal role in PPNs during parasitism. In the context of their hub status and mode of regulation, we suggest alternative strategies for control of PPNs through RNAi approaches.

[Benign struma ovarii: Report of 7 cases and review of the literature]

OBJECTIVE

Struma ovarii is a monodermal teratoma composed of thyroid tissue, representing 0.85 to 1.3% of ovarian tumors. The objective of the present study is to report a continuous series of struma ovarii, with a comprehensive analysis of the literature.

METHODS

A retrospective study in the gynecological surgery department of Hôpital Femme-Mère-Enfant (Hospices Civils de Lyon, Lyon, France) assessed a continuous series of struma ovarii from the Lyon East Pathology Center database. Clinical and biological, imaging and pathological aspects were analyzed and the various forms of treatment described.

RESULTS

We identified 7 patients with struma ovarii from March 2008 to April 2015. Mean patient age was 49.7 years (28-70years). Three patients had a history of thyroid disease. CA-125 was elevated (51IU/mL) in only 1 patient. MRI and ultrasound imaging did not enable diagnosis of struma ovarii, which depended on pathologic examination. Conservative surgery for cystectomy or oophorectomy was performed for patients wishing to become pregnant (71%); nonconservative hysterectomy was performed in postmenopausal women (29%).

CONCLUSIONS

Struma ovarii is a rare, often asymptomatic condition in which diagnosis is difficult. Few series are described in the literature. Here we propose a management model for struma ovarii. Revision surgery and adjuvant therapy is indicated in case of malignant struma ovarii.

Follow-up of differentiated thyroid carcinoma

The aim of follow-up of differentiated thyroid carcinoma (CTD) is the assessment of remission, and, in further steps, the early recognition of patients who develop a recurrence. Tools for the follow-up of CTD include the assessment of thyroglobulin and imaging procedures. Thyroglobulin (Tg) is a strong marker of persistent or recurrent disease, but it must be known that Tg antibodies may give falsely low Tg concentration. TSH stimulation, mainly by the mean of recombinant human TSH, improves the sensitivity of Tg determination. New highly sensitive assays may preclude the need for TSH stimulation, at least in some situations. In the last decades, (131)iodine whole body scan gave place to neck ultrasonography (US) as the most performing imaging procedure in the follow-up of CTD. Criteria to identify cervical lymph node suspect of metastasis have been described, and standardized procedures proposed. Finally, the proof of tumoral invasion is brought by cytological analysis of fine needle biopsies of suspicious lymph nodes. (18)FDG PET is a valuable tool for diagnosis and prognosis in metastatic patients, especially with negative (131)I WBS. Initial response to therapy, assessed by Tg determination and neck US, allows re-stratification of the risk of relapse. According to this "reassessed risk", adapted rhythms and modalities of follow-up have been recently proposed.

(18)F-FDG uptake at initial staging of the adrenocortical cancers: a diagnostic tool but not of prognostic value

BACKGROUND

Adrenocortical carcinoma (ACC) is a rare cancer for which little level evidence exists to guide management. (18)F-FDG PET ((18)F-fluorodeoxyglucose positron emission tomography) is an increasingly used diagnostic tool in patients with suspicious or indeterminate adrenal tumors. In some other solid tumors, (18)F-FDG PET may offer prognostic information that can guide optimal patient treatment. The aim of the present study was to evaluate whether preoperative (18)F-FDG PET based on SUVs assessments has a prognostic value in ACC patients.

METHODS

A retrospective analysis was performed in patients who underwent (18)F-FDG PET/CT for the evaluation of ACC. Inclusion criteria were an unequivocal diagnosis of ACC; all data from primary diagnosis available; (18)F-FDG PET/CT performed prior to surgery or other treatment of the primary tumor; a minimum of 6-months follow-up for surviving patients. All (18)F-FDG PET/CT procedures were reinterpreted in a blind fashion.

RESULTS

Thirty-seven patients (23 without metastasis [M0], 14 with metastasis [M1]) fulfilled the study criteria. Median uptake values were tumor standardized uptake values (SUV)(max) = 11 (range: 3-56) and a tumor/liver SUV(max) ratio = 4.2 (range: 1.3-15). Median follow-up was 20 months. Although classic risk factors (tumoral stage, Weiss score) were associated with poor outcome, there was no correlation between primary tumor FDG uptake with overall survival (OS) and disease free survival (DFS) in M0 patients and with overall survival in M1 patients. (18)F-FDG uptake correlated inconsistently with sinister histological features, such as atypical mitoses or necrosis.

CONCLUSIONS

At initial staging, primary tumor FDG uptake in ACC patients does not correlate with OS and DFS at 2 years. Patient prognosis and treatment strategy should not be based on uptake values.

Burkholderia species are the most common and preferred nodulating symbionts of the Piptadenia group (tribe Mimoseae)

Burkholderia legume symbionts (also called α-rhizobia) are ancient in origin and are the main nitrogen-fixing symbionts of species belonging to the large genus Mimosa in Brazil. We investigated the extent of the affinity between Burkholderia and species in the tribe Mimoseae by studying symbionts of the genera Piptadenia (P.), Parapiptadenia (Pp.), Pseudopiptadenia (Ps.), Pityrocarpa (Py.), Anadenanthera (A.) and Microlobius (Mi.), all of which are native to Brazil and are phylogenetically close to Mimosa, and which together with Mimosa comprise the "Piptadenia group". We characterized 196 strains sampled from 18 species from 17 locations in Brazil using two neutral markers and two symbiotic genes in order to assess their species affiliations and the evolution of their symbiosis genes. We found that Burkholderia are common and highly diversified symbionts of species in the Piptadenia group, comprising nine Burkholderia species, of which three are new ones and one was never reported as symbiotic (B. phenoliruptrix). However, α-rhizobia were also detected and were occasionally dominant on a few species. A strong sampling site effect on the rhizobial nature of symbionts was detected, with the symbiont pattern of the same legume species changing drastically from location to location, even switching from β to α-rhizobia. Coinoculation assays showed a strong affinity of all the Piptadenia group species towards Burkholderia genotypes, with the exception of Mi. foetidus. Phylogenetic analyses of neutral and symbiotic markers showed that symbiosis genes in Burkholderia from the Piptadenia group have evolved mainly through vertical transfer, but also by horizontal transfer in two species.

The Magnaporthe oryzae effector AVR1-CO39 is translocated into rice cells independently of a fungal-derived machinery

Effector proteins are key elements in plant-fungal interactions. The rice blast fungus Magnaporthe oryzae secretes numerous effectors that are suspected to be translocated inside plant cells. However, their cellular targets and the mechanisms of translocation are still unknown. Here, we have identified the open reading frame (ORF3) corresponding to the M. oryzae avirulence gene AVR1-CO39 that interacts with the rice resistance gene Pi-CO39 and encodes a small secreted protein without homology to other proteins. We demonstrate that AVR1-CO39 is specifically expressed and secreted at the plant-fungal interface during the biotrophic phase of infection. Live-cell imaging with M. oryzae transformants expressing a translational fusion between AVR1-CO39 and the monomeric red fluorescent protein (mRFP) indicated that AVR1-CO39 is translocated into the cytoplasm of infected rice cells. Transient expression of an AVR1-CO39 isoform without a signal peptide in rice protoplasts triggers a Pi-CO39-specific hypersensitive response, suggesting that recognition of AVR1-CO39 by the Pi-CO39 gene product occurs in the cytoplasm of rice cells. The native AVR1-CO39 protein enters the secretory pathway of rice protoplasts as demonstrated by the ER localization of AVR1-CO39:mRFP:HDEL translational fusions, and is correctly processed as shown by Western blotting. However, this secreted AVR1-CO39 isoform triggers a Pi-CO39-specific hypersensitive response and accumulates inside rice protoplasts as shown by Western blotting and localization of AVR1-CO39:mRFP translational fusions. This indicates that AVR1-CO39 is secreted by rice protoplasts and re-enters into the cytoplasm by unknown mechanisms, suggesting that translocation of AVR1-CO39 into rice cells occurs independently of fungal factors.

Efficacy and safety of three different cumulative doses of intravenous methylprednisolone for moderate to severe and active Graves' orbitopathy

BACKGROUND

Optimal doses of i.v. glucocorticoids for Graves' orbitopathy (GO) are undefined.

METHODS

We carried out a multicenter, randomized, double-blind trial to determine efficacy and safety of three doses of i.v. methylprednisolone in 159 patients with moderate to severe and active GO. Patients were randomized to receive a cumulative dose of 2.25, 4.98, or 7.47 g in 12 weekly infusions. Efficacy was evaluated objectively at 12 wk by blinded ophthalmologists and subjectively by blinded patients (using a GO specific quality of life questionnaire). Adverse events were recorded at each visit.

RESULTS

Overall ophthalmic improvement was more common using 7.47 g (52%) than 4.98 g (35%; P = 0.03) or 2.25 g (28%; P = 0.01). Compared with lower doses, the high-dose regimen led to the most improvement in objective measurement of ocular motility and in the Clinical Activity Score. The Clinical Activity Score decreased in all groups and to the least extent with 2.25 g. Quality of life improved most in the 7.47-g group, although not reaching statistical significance. No significant differences occurred in exophthalmos, palpebral aperture, soft tissue changes, and subjective diplopia score. Dysthyroid optic neuropathy developed in several patients in all groups. Because of this, differences among the three groups were no longer apparent at the exploratory 24-wk visit. Major adverse events were slightly more frequent using the highest dose but occurred also using the lowest dose. Among patients whose GO improved at 12 wk, 33% in the 7.47-group, 21% in the 4.98-group, and 40% in the 2.25-group had relapsing orbitopathy after glucocorticoid withdrawal at the exploratory 24-wk visit.

CONCLUSIONS

The 7.47-g dose provides short-term advantages over lower doses. However, this benefit is transient and associated with slightly greater toxicity. The use of a cumulative dose of 7.47 g of methylprednisolone provides short-term advantage over lower doses. This may suggest that an intermediate-dose regimen be used in most cases and the high-dose regimen be reserved to most severe cases of GO.

Plant defensin AhPDF1.1 is not secreted in leaves but it accumulates in intracellular compartments

• Apart from their antifungal role, plant defensins have recently been shown to be involved in abiotic stress tolerance or in inhibition of root growth when added in plant culture medium. We studied the subcellular localization of these proteins, which may account for these different roles. • Stable and transient expression of AhPDF1.1::GFP (green fluorescent protein) fusion proteins were analysed in yeast and plants. Functional tests established that the GFP tag did not alter the action of the defensin. Subcellular localization of AhPDF1.1 was characterized: by imaging AhPDF1.1::GFP together with organelle markers; and by immunolabelling AhPDF1.1 in Arabidopsis halleri and Arabidopsis thaliana leaves using a polyclonal serum. • All our independent approaches demonstrated that AhPDF1.1 is retained in intracellular compartments on the way to the lytic vacuole, instead of being addressed to the apoplasm. • These findings challenge the commonly accepted idea of secretion of defensins. The subcellular localization highlighted in this study could partly explain the dual role of plant defensins on plant cells and is of major importance to unravel the mechanisms of action of these proteins at the cellular level.

Molecular diversity and gene expression of cotton ERF transcription factors reveal that group IXa members are responsive to jasmonate, ethylene and Xanthomonas

Several ethylene-response factor (ERF) transcription factors are believed to play a crucial role in the activation of plant defence responses, but little is known about the relationships between the diversity of this family and the functions of groups or individual ERFs in this process. In this study, 200 ERF genes from the unigene cotton database were identified. Conserved amino acid residues and phylogeny reconstruction using the AP2 conserved domain suggest that the classification into 10 major groups used for Arabidopsis and rice is applicable to the cotton ERF family. Based on in silico studies, we predict that group IX ERF genes in cotton are involved in jasmonate (JA), ethylene (ET) and pathogen responses. To test this hypothesis, we analysed the transcript profiles of the group IXa subfamily in the regulation of specific resistance to Xanthomonas campestris pathovar malvacearum. The expression of four members of group IXa was induced on challenge with X. campestris pv. malvacearum. Furthermore, the expression of several ERF genes of group IXa was induced synergistically by JA in combination with ET, suggesting that the encoded ERF proteins may play key roles in the integration of both signals to activate JA- and ET-dependent responses.

Assessment of the incremental value of recombinant thyrotropin stimulation before 2-[18F]-Fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography imaging to localize residual differentiated thyroid cancer

PURPOSE

The purpose of the study was to assess prospectively the impact of recombinant human TSH (rhTSH) administration on positron emission tomography (PET)/computed tomography (CT) imaging in differentiated thyroid cancer patients who, after primary treatment, had a suppressed or stimulated serum thyroglobulin greater than 10 ng/ml and no radioactive iodine uptake consistent with thyroid cancer on a whole body scan.

PATIENTS AND METHODS

PET/CT was performed before (basal PET) and 24-48 h after rhTSH administration (rhTSH-PET) in 63 patients (52 papillary and 11 follicular thyroid cancers). Images were blindly analyzed by two readers. The proposed treatment plan was prospectively assessed before basal PET, after basal PET, and again after rhTSH-PET.

RESULTS

A total of 108 lesions were detected in 48 organs in 30 patients. rhTSH-PET was significantly more sensitive than basal PET for the detection of lesions (95 vs. 81%; P = 0.001) and tended to be more sensitive for the detection of involved organs (94 vs. 79%; P = 0.054). However, basal PET and rhTSH-PET did not have significantly different sensitivity for detecting patients with any lesions (49 vs. 54%; P = 0.42). Changes in treatment management plan occurred in 19% of the patients after basal PET. Lesions found only by rhTSH-PET contributed to an altered therapeutic plan in eight patients, among whom only four were true-positive on pathology (6%).

CONCLUSION

The use of rhTSH for 2-[18F]-fluoro-2-deoxy-D-glucose-PET/CT significantly increased the number of lesions detected, but the numbers of patients in whom any lesion was detected were no different between basal and rhTSH-stimulated PET/CT scans. Treatment changes due to true positive lesions occurred in 6% of cases.

Familial pituitary adenomas with a heterogeneous functional pattern: clinical and genetic features

Familial pituitary adenoma is a rare syndrome which may present either as isolated lesions, or in association with other endocrine tumors, for example in the frame of multiple endocrine neoplasia (MEN-1) or Carney complex (CNC). The most frequently described forms of familial isolated pituitary adenoma (FIPA) are familial somatotropinomas or prolactinomas. Recently, some cases of familial isolated somatotropinoma have been associated with germline mutations in the aryl hydrocarbon receptor interacting protein (AIP) gene. The present report shows heterogeneous FIPA with 3 subtypes of tumor in 3 individuals of the same family: somatotropinoma in the proband, giant prolactinoma in a brother, and gonadotroph cell macroadenoma in the father. A prospective survey also suggested the occurrence of a silent microadenoma in the proband's sister. Clinical screening was performed in the 3 affected members, the 4th suspected case, and 9 additional, asymptomatic relatives. They had no clinical evidence of associated endocrine lesion suggesting MEN-1 or CNC. Genetic screening for germline mutation of the MEN-1, the gene encoding the protein kinase A (PKA) type 1 alpha regulatory subunit (R1 alpha) (PRKAR1alpha) and AIP gene was negative in 2 affected members. In conclusion, these data suggest that familial pituitary adenomas can occur with a heterogeneous functional pattern that is distinguished from MEN-1 or CNC. The absence of mutation of the recently described AIP gene suggests the implication of other predisposing gene(s). Collaborative, multicentric studies are needed to further define the location of gene(s) involved in heterogeneous FIPA.

[A case of hyperthyroidism due to functioning metastasis of differentiated thyroid carcinoma. Discussion and literature review]

We report on a very rare case of hyperthyroidism due to multiple autonomously functioning bone metastasis of papillary thyroid cancer in a 79-year-old woman. This situation remains extremely uncommon, as shown by our review of the literature; only 47 similar cases have been published from 1946 to 2005. The pathogenic mechanism remains largely unknown in spite of several hypotheses (conjunction in volume and differentiation, auto-antibodies). Hyperthyroidism can be severe, and often T3 levels are markedly more elevated than T4 levels. Apart from hyperthyroidism caused by the hormone-production, clinical features are similar to that of usual metastatic thyroid cancer, occurring in elderly women in most cases, and of follicular type on pathology. Metastases mostly occur in bones and lungs. Treatment relies mainly on radio-iodine ((131)I), which is efficient on hormonal disorders, and prognosis appears to be correlated with the ability of the metastatic sites to concentrate radio-iodine.

Hürthle cell thyroid carcinoma metastatic to the sigmoid colon

Prognosis of differentiated thyroid cancer is favorable in the majority of cases. However, distant metastases occur in 10-15% of cases, predominantly in lungs and bones, especially in older patients exhibiting poorly differentiated forms or advanced stages. We report a case history of Hürthle cell thyroid carcinoma metastasized to the sigmoid colon. To the best of our knowledge, this location has never been described before. This case history illustrates the difficulties of diagnosis and treatment in patients whose metastases do not concentrate radioiodine. The interest of different imaging modalities, including fluoro-deoxy-glucose positron emission tomography scan and somatostatin receptor scintigraphy, is discussed.

[Screening for bacteriuria in diabetic patients. Is it possible to stop systematic urine cytobacteriological testing?]

OBJECTIVES AND METHOD

The discordance between test by urine dipstick (nitrites and leucocyte-esterase) and analysis in laboratory, with urinary culture on the same sample was studied in diabetic patients, from October 2000 to May 2002, to eventually stop systematic laboratory test. The dipstick result (Clinitek 20 Bayer) was classified as "possibility of bacteriuria" if one of the two tests was positive. Bacteriuria was considered significant if the laboratory test result gave, at least 10(5) bacteria per mL, (one strain), and at least 10(4) leucocytes. The out point was the dipstick negative predictive value (NPV).

RESULTS

The study included 683 patients. The dipstick result was "possibility of bacteriuria" in 153 cases (22.4%). Thirty-nine bacteriuria (5.7%) were reported, including 2 dipstick false negatives. The NPV was 99.6% [IC 95% : 99.1-100].

CONCLUSION

The systematic laboratory tests were stopped.

Highly functionalized cyclopentanes from meso bicyclic hydrazines. A rapid access to mannosidase inhibitors

A simple diastereoselective access to amino- and hydrazinocyclopentitols is described. The key step involves a cationic rearrangement of a meso bicyclic hydrazine, followed by two successive stereoselective hydroxylations. Both racemic compounds are micromolar alpha-mannosidase (Jack bean) inhibitors.

Iodine excess and thyroid autoimmunity

Epidemiological studies, as well as animal models, indicate that iodine might be an immunogenic agent for the thyroid gland, at least in subjects predisposed to thyroid autoimmunity. This review presents data, either epidemiological or experimental, obtained in different conditions: constant and stable iodine status, either deficient, sufficient or excessive; long-term iodine prophylaxis; temporary supplementation with iodide (6-12 months) or iodised oil. Moreover, we also discuss data obtained in the general population, among subjects with euthyroid goiter, or autoimmune goiter, or even in women prone to post-partum thyroid diseases. It is concluded that the significant increase in the prevalence of autoimmune thyroid diseases in populations living in iodine sufficient areas should not prevent the implementation of the iodine prophylaxis.