Insights on Host-Parasite Immunomodulation Mediated by Extracellular Vesicles of Cutaneous Leishmania shawi and Leishmania guyanensis

Leishmaniasis is a parasitic disease caused by different species of Leishmania and transmitted through the bite of sand flies vector. Macrophages (MΦ), the target cells of Leishmania parasites, are phagocytes that play a crucial role in the innate immune microbial defense and are antigen-presenting cells driving the activation of the acquired immune response. Exploring parasite-host communication may be key in restraining parasite dissemination in the host. Extracellular vesicles (EVs) constitute a group of heterogenous cell-derived membranous structures, naturally produced by all cells and with immunomodulatory potential over target cells. This study examined the immunogenic potential of EVs shed by L. shawi and L. guyanensis in MΦ activation by analyzing the dynamics of major histocompatibility complex (MHC), innate immune receptors, and cytokine generation. L. shawi and L. guyanensis EVs were incorporated by MΦ and modulated innate immune receptors, indicating that EVs cargo can be recognized by MΦ sensors. Moreover, EVs induced MΦ to generate a mix of pro- and anti-inflammatory cytokines and favored the expression of MHCI molecules, suggesting that EVs antigens can be present to T cells, activating the acquired immune response of the host. Since nano-sized vesicles can be used as vehicles of immune mediators or immunomodulatory drugs, parasitic EVs can be exploited by bioengineering approaches for the development of efficient prophylactic or therapeutic tools for leishmaniasis.

Antagonist G-targeted liposomes for improved delivery of anticancer drugs in small cell lung carcinoma

Ligand-mediated targeted liposomes have the potential to increase therapeutic efficacy of anticancer drugs. This work aimed to evaluate the ability of antagonist G, a peptide targeting agent capable of blocking the action of multiple neuropeptides, to selectivity improve targeting and internalization of liposomal formulations (long circulating liposomes, LCL, and stabilized antisense lipid particles containing ionizable amino lipid, SALP) to H69 and H82 small cell lung carcinoma (SCLC) cell lines. Antagonist G-targeted LCL and SALP were prepared by two different methods (either by direct covalent linkage at activated PEG grafted onto the liposomal surface or by post-insertion of DSPE-PEG-antagonist-G-conjugates into pre-formed liposomes). Association of the liposomal formulations with target SCLC cells was studied by fluorescence microscopy using fluorescence-labelled liposomes and confirmed quantitatively with [³H]-CHE-labelled liposomes. An antisense oligodeoxynucleotide against the overexpressed oncogene c-myc(as(c-myc)) was efficiently loaded into SALP formulations, the encapsulation efficiency decreased due to the inclusion of the targeting ligand. Also, liposome size was affected by as(c-myc) physical chemical properties. The amount of antagonist G linked to the surface of the liposomal formulations was dependent on the coupling method and lipid composition used. Covalent attachment of antagonist G increased liposomes cellular association and internalization via receptor-mediated and clathrin-dependent endocytosis, as assessed in SCLC cell lines. Biodistribution studies in healthy mice revealed a preferential lung accumulation of antagonist G-targeted SALP as compared to the non-targeted counterpart. Lung levels of the former were up to 3-fold higher 24 h after administration, highlighting their potential to be used as delivery vectors for SCLC treatment.

Oral Efficacy of a Diselenide Compound Loaded in Nanostructured Lipid Carriers in a Murine Model of Visceral Leishmaniasis

Leishmaniasis urgently needs new oral treatments, as it is one of the most important neglected tropical diseases that affects people with poor resources. The drug discovery pipeline for oral administration currently discards entities with poor aqueous solubility and permeability (class IV compounds in the Biopharmaceutical Classification System, BCS) such as the diselenide 2m, a trypanothione reductase (TR) inhibitor. This work was assisted by glyceryl palmitostearate and diethylene glycol monoethyl ether-based nanostructured lipid carriers (NLC) to render 2m bioavailable and effective after its oral administration. The loading of 2m in NLC drastically enhanced its intestinal permeability and provided plasmatic levels higher than its effective concentration (IC50). In L. infantum-infected BALB/c mice, 2m-NLC reduced the parasite burden in the spleen, liver, and bone marrow by at least 95% after 5 doses, demonstrating similar efficacy as intravenous Fungizone. Overall, compound 2m and its formulation merit further investigation as an oral treatment for visceral leishmaniasis.

Topical Allopurinol-Loaded Nanostructured Lipid Carriers: A Novel Approach for Wound Healing Management

Nanostructured lipid carriers (NLC) have been widely studied as delivery systems for a variety of routes, including the skin. Their composition results in an imperfect lipid matrix, allowing increased drug encapsulation. Allopurinol (AP), a xanthine oxidase inhibitor, is characterized by low water solubility and high melting point, which has hampered its use through the topical route. In this work, AP was incorporated in a NLC formulation to enhance drug-carrier association and skin delivery as a topical approach to treat wounds. AP-NLC system was characterized in terms of size, charge, rheological behavior, and in vitro skin permeation. The in vitro cytotoxicity was evaluated using HaCaT cells. The wound healing efficacy of the AP-NLC formulation on animal skin lesions was evaluated in male Wistar rats. The AP-NLC presented a mean size of 193 ± 15 nm with a PdI of 0.240 ± 0.02, zeta potential values around −49.6 mV, and an encapsulation efficiency of 52.2%. The AP-NLC formulation presented an adequate profile to be used topically, since epidermal and dermal drug retention were achieved. No reduction in HaCaT cells viability was observed at the tested concentrations (AP < 10 μg/mL). The in vivo application of the AP-NLC formulation resulted in the regeneration of skin lesions when compared with non-treated controls.

Novel Antiretroviral Therapeutic Strategies for HIV

When the first cases of HIV infection appeared in the 1980s, AIDS was a deadly disease without any therapeutic alternatives. Currently, there is still no cure for most cases mainly due to the multiple tissues that act as a reservoir for this virus besides the high viral mutagenesis that leads to an antiretroviral drug resistance. Throughout the years, multiple drugs with specific mechanisms of action on distinct targets have been approved. In this review, the most recent phase III clinical studies and other research therapies as advanced antiretroviral nanodelivery systems will be here discussed. Although the combined antiretroviral therapy is effective in reducing viral loading to undetectable levels, it also presents some disadvantages, such as usual side effects, high frequency of administration, and the possibility of drug resistance. Therefore, several new drugs, delivery systems, and vaccines have been tested in pre-clinical and clinical trials. Regarding drug delivery, an attempt to change the route of administration of some conventional antiretrovirals has proven to be successful and surpassed some issues related to patient compliance. Nanotechnology has brought a new approach to overcoming certain obstacles of formulation design including drug solubility and biodistribution. Overall, the encapsulation of antiretroviral drugs into nanosystems has shown improved drug release and pharmacokinetic profile.

Amphotericin B-loaded deformable lipid vesicles for topical treatment of cutaneous leishmaniasis skin lesions

Cutaneous leishmaniasis (CL), the most common clinical form of human leishmaniasis, is a non-fatal chronic and disabling disease characterized by erythema and nodular or ulcerative skin lesions that may cause permanent scars and disfigurement. Topical drug delivery represents a simple and efficacious approach to treat CL skin lesions. The association of drugs with nanocarrier systems enhances their permeation properties and increases the drug amount available in the dermis. Here, a deformable lipid vesicle (DLV) was optimized for the topical administration of Amphotericin B (AmB), with the aim of studying and understanding the advantages of this type of delivery system in the transport of a drug through the skin layers. AmB-DVL were characterized in terms of incorporation parameters, stability, and elasticity, and evaluated in vitro for their permeation properties, cytotoxicity, and anti-leishmanial activity. The AmB-DVL exhibited a translucent fluid gel-like aspect and a yellow color, a mean size of 132 nm (PdI ≤ 0.1), zeta potential values around zero (mV), and an AmB incorporation efficiency of 95%. Permeation and penetration assays suggest that AmB-DLV are suitable for topical administration since AmB was detected in the epidermal and dermal skin layers. AmB-DVL was able to reduce promastigote viability in a dose-dependent manner, as well as the number of intracellular amastigotes in THP-1 macrophages. Selectivity index (SI) value for AmB-DLV was considerably higher than that observed for free AmB. Results suggest that DLV may represent an attractive vehicle for dermal delivery of AmB and a new low-cost and safe therapeutic option in CL treatment.

Targeted delivery in scleroderma fibrosis

Systemic sclerosis (SSc) is considered one of the most challenging and difficult to treat among rheumatic disorders, due to its severity, multiorgan manifestation and different outcomes. It manifests fibrosis in different organs, mostly in skin and lungs. The skin fibrosis expression is considered the first sign of the disease and usually it is followed by internal organ fibrosis. An aberrant immune system activation seems to relate to the expression of the disease, but even environmental influences and dysregulation of many molecules signalling pathways are involved in the development of the disease. Current therapies are limited and characterized by multiple side effects: systemic route is the elective administration route, which decreases patient adherence to the therapy, as they are often already bothered by pain and disfigurement. Treatments available are organ-based, originally indicated for other conditions and there is no therapy available to reduce the fibroblast population size within existing fibrotic lesions. Disease-modifying therapies or immunomodulatory agents that are highly effective in other rheumatic diseases have shown disappointing results in SSc. There are thus no standardized and effective treatments for this disease, and there are even unanswered questions related to the insurgence of the pathology and all the mechanisms involved. An ideal approach could be considered "targeted therapy" that will be an increasingly attainable objective insofar as our understanding of the disease improves. The advantages in identifying the molecule and the signalling pathways involved in the pathology have helped to find some novel compounds for the therapy of scleroderma fibrosis or following innovative uses for already-approved drugs, corroborated by many clinical studies.

The Secretome Derived From 3D-Cultured Umbilical Cord Tissue MSCs Counteracts Manifestations Typifying Rheumatoid Arthritis

Rheumatoid arthritis (RA) is an autoimmune disorder whose treatment is mostly restricted to pain and symptom management and to the delay of joint destruction. Mesenchymal stem/stromal cells from the umbilical cord tissue (UC-MSCs) have previously been proven to be immunomodulatory and more efficient than bone marrow-derived MSCs in causing remission of local and systemic arthritic manifestations in vivo. Given the paracrine nature of UC-MSC activity, their application as active substances can be replaced by their secretome, thus avoiding allogeneic rejection and safety issues related to unwanted grafting. In this work, we aimed at demonstrating the viability of applying the 3D-primed UC-MSC secretome for the amelioration of arthritic signs. A proteomic analysis was performed to both, media conditioned by UC-MSC monolayer (CM2D) and 3D cultures (CM3D). The analysis of relevant trophic factors confirmed secretome profiles with very significant differences in terms of therapeutic potential. Whereas, CM3D was characterised by a prevailing expression of anti-inflammatory cytokines such as IL-10 and LIF, along with trophic factors involved in different mechanisms leading to tissue regeneration, such as PDGF-BB, FGF-2, I-309, SCF, and GM-CSF; CM2D presented relatively higher levels of IL-6, MCP-1, and IL-21, with recognised pro-inflammatory roles in joint disease and pleiotropic effects in the progression of rheumatoid arthritis (RA). Accordingly, different motogenic effects over mouse chondrocytes and distinct capacities of inducing glycosaminoglycan synthesis in vitro were observed between CM3D and CM2D. Finally, the evaluation of arthritic manifestations in vivo, using an adjuvant-induced model for arthritis (AIA), suggested a significantly higher therapeutic potential of CM3D over CM2D and even UC-MSCs. Histological analysis confirmed a faster remission of local and systemic arthritic manifestations of CM3D-treated animals. Overall, the results show that the use of UC-MSC CM3D is a viable and better strategy than direct UC-MSC administration for counteracting AIA-related signs. This strategy represents a novel MSC-based but nonetheless cell-free treatment for arthritic conditions such as those characterising RA.

Lipid-Based Nanocarriers for Cutaneous Leishmaniais and Buruli Ulcer Management

Infectious diseases in the skin represent a major group of pathologies that contribute annually for significant health economic expenses. According to WHO, Buruli Ulcer (BU) and Cutaneous Leishmaniasis (CL) are two neglected tropical diseases for which therapy remains inadequate. Topical delivery of therapeutics constitutes an advantageous alternative to treat infected skin lesions as it allows a direct treatment of affected areas avoiding unwanted systemic effects and reducing the drug dosage. However, effective topical delivery of antimicrobial agents is still a challenge. The emergence of difficult-to-treat skin mycobacteriosis such as BU or the increasing incidence of CL highlights the need for new antimicrobial agents and new delivery systems. In the present review problems related to mycobacterial and parasitic infected skin lesions will be particularly focused as well as new alternative strategies for their treatment. Currently, progresses and challenges in constructing nanocarrier platforms for delivering various antimicrobial drugs for infected skin lesions have been attempted. This article reviews the potential of these nanocarriers in the treatment of cutaneous infections, especially regarding mycobacteria and Leishmania caused skin lesions. Nanostructured biomaterials, such as lipid-based nanocarriers, have unique physicochemical properties enabling the topical application of antimicrobial drugs, thereby overcoming some of the limitations of conventional therapies. These nanosystems have been investigated for the topical delivery of well-known drugs or new therapeutic candidates. This approach is just the beginning of a stimulating nanotechnological area.

Cytotoxic effect of the serotonergic drug 1-(1-Naphthyl)piperazine against melanoma cells

1-(1-Naphthyl)piperazine (1-NPZ) is a serotonergic derivative of quipazine acting both as antagonist and agonist of different serotonin receptors, with promising results for the management of skin cancer. In this work, we studied the effect of 1-NPZ on human MNT-1 melanoma cells by evaluating its effects on cell viability, ability to form colonies, cell cycle dynamics, reactive oxygen species (ROS) production and apoptosis. Treatment of MNT-1 cells with 1-NPZ for 24h decreased cell viability and induced apoptosis in a dose-dependent manner. Activity against melanoma was confirmed with a different melanoma cell line, SK-MEL-28. Simultaneously, 1-NPZ affected cell cycle progression by mediating a S-phase delay. Higher levels of ROS were also detected in MNT-1 cells after treatment with 1-NPZ. Furthermore, 1-NPZ significantly increased the expression of cyclooxygenase-2 in MNT-1 cells. These findings suggest that 1-NPZ pretreatment is able to induce oxidative stress, and consequently apoptotic cell death in melanoma cells. In conclusion, this study demonstrates the cytotoxic and genotoxic potential of 1-NPZ against melanoma cells.

Stability effect of cholesterol-poly(acrylic acid) in a stimuli-responsive polymer-liposome complex obtained from soybean lecithin for controlled drug delivery

The development of polymer-liposome complexes (PLCs), in particular for biomedical applications, has grown significantly in the last decades. The importance of these studies comes from the emerging need in finding intelligent controlled release systems, more predictable, effective and selective, for applications in several areas, such as treatment and/or diagnosis of cancer, neurological, dermatological, ophthalmic and orthopedic diseases, gene therapy, cosmetic treatments, and food engineering. This work reports the development and characterization of a pH sensitive system for controlled release based on PLCs. The selected hydrophilic polymer was poly(acrylic acid) (PAA) synthesized by atom transfer radical polymerization (ATRP) with a cholesterol (CHO) end-group to improve the anchoring of the polymer into the lipid bilayer. The polymer was incorporated into liposomes formulated from soybean lecithin and stearylamine, with different stearylamine/phospholipid and polymer/phospholipid ratios (5, 10 and 20%). The developed PLCs were characterized in terms of particle size, polydispersity, zeta potential, release profiles, and encapsulation efficiency. Cell viability studies were performed to assess the cytotoxic potential of PLCs. The results showed that the liposomal formulation with 5% of stearylamine and 10% of polymer positively contribute to the stabilization of the complexes. Afterwards, the carboxylic acid groups of the polymer present at the surface of the liposomes were crosslinked and the same parameters analyzed. The crosslinked complexes showed to be more stable at physiologic conditions. In addition, the release profiles at different pHs (2-12) revealed that the obtained complexes released all their content at acidic conditions. In summary, the main accomplishments of this work are: (i) innovative synthesis of cholesterol-poly(acrylic acid) (CHO-PAA) by ATRP; (ii) stabilization of the liposomal formulation by incorporation of stearylamine and CHO-PAA; (iii) new approach for CHO-PAA crosslinking, resulting in more stable PLCs at physiological conditions; (iv) destabilization of PLCs upon slight changes of pH, showing their pH sensitivity; and (v) the PLCs do not exhibit cellular toxicity.

Lipid-based nanoformulations of trifluralin analogs in the management of Leishmania infantum infections

Aim: To improve the potential of trifluralin (TFL) in the management of Leishmania infantum infections through the synthesis of analogs (TFLA) and incorporation in nanoparticulate drug delivery systems (NanoDDS), liposomes and solid lipid nanoparticles, for selective targeting to leishmania infection sites. Material & methods: In vitro screening of 18 TFLA was performed by flow cytometry. NanoDDS were loaded with active TFLA and evaluated for antileishmanial efficacy in mice through determination of parasite burden in liver and spleen. Results: The in vitro testing revealed the most active and nontoxic TFLAs, which were selected for the in vivo studies based on high incorporation in liposomes and lipid nanoparticles (>90%). Selected TFLA nanoformulations showed superior antileishmanial activity in mice (parasite burden >80%), over free TFLA and Glucantime. Conclusion: The modification of TFL structure to obtain active TFLA, together with their incorporation in NanoDDS, improved their in vivo performance against L. infantum infection.

Liposomes versus lipid nanoparticles: comparative study of lipid-based systems as oryzalin carriers for the treatment of leishmaniasis

Main-stay in treatment of leishmaniasis relies on chemotherapy but none of the current drugs combines high activity and low toxicity at affordable costs. Dinitroanilines are a new class of drugs with proved in vitro antileishmanial activity. However the development of their pharmaceutical formulations has been compromised by low water solubility and low accumulation in diseased organs. These limitations can be overcome by incorporation in lipid-based nanoformulations such as liposomes and solid lipid nanoparticles. In previous work this strategy was already followed with the incorporation of a dinitroaniline, oryzalin, resulting in the improvement of the biodistribution profile. The present work aims at demonstrating the in vitro and in vivo therapeutic activity of these oryzalin nanoformulations, and establishing a systematic comparison of both systems. After oryzalin incorporation suitable physicochemical properties for parenteral administration were obtained. Nanoformulations revealed reduced cytotoxicity and haemolytic activity when compared with free-oryzalin, while retaining the in vitro intracellular activity. Therapeutic activity, assessed in a murine model of visceral leishmaniasis, was evaluated in terms of number of administrations, dose-response and influence of the lipid excipient. Results demonstrate the superiority of both oryzalin nanoformulations on the reduction of parasitic burden in liver and spleen as compared to the control group (84 to 91%) and similar to Glucantime. A strong reduction in ED50 values (3 to 65 fold) as compared to free-oryzalin was also obtained, depending on the organ and nanoformulation used. Both oryzalin nanoformulations are potential candidates as therapeutic agents against visceral leishmaniasis.

TERT promoter mutations are a major indicator of poor outcome in differentiated thyroid carcinomas

CONTEXT

Telomerase promoter mutations (TERT) were recently described in follicular cell-derived thyroid carcinomas (FCDTC) and seem to be more prevalent in aggressive cancers.

OBJECTIVES

We aimed to evaluate the frequency of TERT promoter mutations in thyroid lesions and to investigate the prognostic significance of such mutations in a large cohort of patients with differentiated thyroid carcinomas (DTCs).

DESIGN

This was a retrospective observational study.

SETTING AND PATIENTS

We studied 647 tumors and tumor-like lesions. A total of 469 patients with FCDTC treated and followed in five university hospitals were included. Mean follow-up (±SD) was 7.8 ± 5.8 years.

MAIN OUTCOME MEASURES

Predictive value of TERT promoter mutations for distant metastasization, disease persistence at the end of follow-up, and disease-specific mortality.

RESULTS

TERT promoter mutations were found in 7.5% of papillary carcinomas (PTCs), 17.1% of follicular carcinomas, 29.0% of poorly differentiated carcinomas, and 33.3% of anaplastic thyroid carcinomas. Patients with TERT-mutated tumors were older (P < .001) and had larger tumors (P = .002). In DTCs, TERT promoter mutations were significantly associated with distant metastases (P < .001) and higher stage (P < .001). Patients with DTC harboring TERT promoter mutations were submitted to more radioiodine treatments (P = .009) with higher cumulative dose (P = .004) and to more treatment modalities (P = .001). At the end of follow-up, patients with TERT-mutated DTCs were more prone to have persistent disease (P = .001). TERT promoter mutations were significantly associated with disease-specific mortality [in the whole FCDTC (P < .001)] in DTCs (P < .001), PTCs (P = .001), and follicular carcinomas (P < .001). After adjusting for age at diagnosis and gender, the hazard ratio was 10.35 (95% confidence interval 2.01-53.24; P = .005) in DTC and 23.81 (95% confidence interval 1.36-415.76; P = .03) in PTCs.

CONCLUSIONS

TERT promoter mutations are an indicator of clinically aggressive tumors, being correlated with worse outcome and disease-specific mortality in DTC. TERT promoter mutations have an independent prognostic value in DTC and, notably, in PTC.

Stimulated thyroglobulin at recombinant human TSH-aided ablation predicts disease-free status one year later

CONTEXT

Thyroglobulin (Tg) levels measured at the time of remnant ablation after thyroid hormone withdrawal (THW) were shown to have prognostic value in predicting disease-free status.

OBJECTIVES

Our objectives were to determine whether stimulated Tg levels, measured at the time of remnant ablation performed under recombinant human TSH (rhTSH) stimulation, has value in predicting absence of detectable disease 1 year after radioiodine therapy and to compare the results obtained with this approach with a cohort of patients submitted to ablation after THW.

DESIGN

This was a prospective observational study.

SETTING AND PATIENTS

The study included 293 consecutive patients treated for a differentiated thyroid carcinoma with no initial evidence of distant metastasis. All patients were submitted to a total or near-total thyroidectomy, followed by ablation either under rhTSH (n = 151) or endogenous TSH stimulation (n = 142). Patients with positive Tg antibodies were excluded.

MAIN OUTCOME MEASURES

The predictive value of Tg at ablation was assessed by receiver operating characteristic curve analysis.

RESULTS

In the rhTSH group, 96 patients (73.3%) were considered disease-free at 1 year. Stimulated Tg at ablation after rhTSH was found to be an independent prognostic indicator of disease persistence 12 months later. The highest-accuracy cutoff value for absence of detectable disease was defined as 7.2 ng/mL, with a negative predictive value of 90%. In the THW group, Tg at ablation also proved to have independent predictive value. Using the same threshold (7.2 ng/mL), the negative predictive value of Tg was 95% in the THW group.

CONCLUSIONS

When rhTSH was used, stimulated Tg at ablation had independent predictive value for disease-free status 1 year later. A low stimulated Tg at rhTSH-aided ablation may be considered a favorable prognosis factor.

Giant macroprolactinoma and pregnancy

Prolactinomas are a common cause of gonadal dysfunction and infertility. We present the case of a 38-year-old woman with history of amenorrhea and infertility. At seven weeks of pregnancy she presented neuro-ophthalmologic complaints of headaches, diplopia, and right ptosis. The work-up study revealed an invasive pituitary macroadenoma with a maximum diameter of 9 cm and serum prolactin of 25,800 ng/mL (3-20). At 12 weeks, she was referred to the Endocrinology Department of the Coimbra University Hospital and started therapy with bromocriptine, initially 5 mg/day and then at crescent doses. Hyperprolactinemia was rapidly and drastically reduced to 254 ng/mL three weeks after taking bromocriptine 15 mg/day. Tumoral volume was reduced and there was improvement of III pair paresis. At 38 weeks, a male healthy baby was born. This is a relevant clinical case that illustrates the efficacy and safety of bromocriptine therapy during pregnancy, even in severe cases like this one.

MR fat fraction mapping: a simple biomarker for liver steatosis quantification in nonalcoholic fatty liver disease patients

RATIONALE AND OBJECTIVES

To assess the performance, postprocessing time, and intra- and interobserver agreement of a simple magnetic resonance-based mapping technique to quantify liver fat.

MATERIALS AND METHODS

This prospective, single-center study included 26 patients who were overweight with type 2 diabetes and at risk for nonalcoholic fatty liver disease. Mapping of the liver was based on a triple echo gradient-echo sequence, and (1)H magnetic resonance spectroscopy was used as the reference standard. The nonparametric Spearman correlation coefficient and the Wilcoxon test were used for comparisons between mapping and spectroscopy. The mapping was assessed for its predictive performance using the area under the curve of a receiver operating characteristic curve. Intraclass correlation coefficients were used to calculate intra- and interobserver's agreement for mapping measurements.

RESULTS

Patients had a mean fat percentage of 11.7% (range, 2-35.4%). A strong correlation was seen between mapping and spectroscopy (r = 0.89, P < .0001). A cutoff of 6.9% for fat fraction mapping was found to diagnose steatosis with 93% sensitivity and 100% specificity with an area under the curve of 0.99. Mapping of the liver had shorter acquisition and post-processing times than spectroscopy (5 min vs. 38 min; P < .0001). Mapping measurements had an intra- and interobserver agreement of 0.98 and 0.99, respectively.

CONCLUSIONS

The magnetic resonance-based liver mapping can accurately quantify liver fat with a cutoff value of 6.9% and excellent intra- and interobserver agreement. This mapping technique, with its simple methodology and short postprocessing time, has the potential to be included in routine abdominal protocols.

Persistent primary hyperparathyroidism: an uncommon location for an ectopic gland - Case report and review

Primary hyperparathyroidism (PHPT) is a common endocrine disorder that mainly affects middle-aged women. Patients are usually asymptomatic. The disease might be ascribable to hyperplasia, carcinoma, and single or multiple adenomas. PHPT may be sporadic or familial, the latter comprising multiple endocrine neoplasia type 1 or 2A, familial benign hypocalciuria hypercalcemia, and hyperparathyroidism-jaw tumor syndrome. The most common causes for persistent PHPT are multiglandular disease, and missed abnormal ectopic or orthotopic parathyroid glands. Imaging localization studies should precede a new surgical intervention. Ectopic parathyroid glands are rarely located at the aortopulmonary window. For diagnosis confirmation, 99mTc-sestamibi SPECT/CT seems to be an advantageous test. Another possibility is to perform 99mTc-sestamibi followed by thoracic CT or MRI. Parathyroidectomy may be performed by means of median sternotomy, thoracotomy, or video-assisted thoracoscopy. We describe a case of persistent primary hyperparathyroidism due to the presence of an ectopic parathyroid gland found at the aortopulmonary window. As the investigation necessary to clarify the etiology of recurrent nephrolithiasis proceeded, the diagnosis of PHPT was determined. The patient underwent subtotal parathyroidectomy; nevertheless, PHPT persisted. Genetic syndromes that could account for this condition were excluded. Imaging studies available at that time were not able to locate abnormal glands; moreover, the patient refused to undergo surgical exploration. Later, the patient underwent 99mTc-sestamibi SPECT/CT, which revealed a parathyroid gland at the aortopulmonary window.

Sources of hepatic glycogen synthesis following a milk-containing breakfast meal in healthy subjects

During feeding, dietary galactose is a potential source of hepatic glycogen synthesis; but its contribution has not been measured to date. In the presence of deuterated water ((2)H(2)O), uridine diphosphate (UDP)-glucose derived from galactose is not enriched, whereas the remainder derived from glucose-6-phosphate (G6P) is enriched in position 2 to the same level as body water, assuming complete G6P-fructose-6-phosphate (F6P) exchange. Hence, the difference between UDP-glucose position 2 and body water enrichments reflects the contribution of galactose to glycogen synthesis relative to all other sources. In study 1, G6P-F6P exchange in 6 healthy subjects was quantified by supplementing a milk-containing breakfast meal with 10 g of [U-(2)H(7)]glucose and quantifying the depletion of position 2 enrichment in urinary menthol glucuronide. In study 2, another 6 subjects ingested (2)H(2)O and acetaminophen followed by an identical breakfast meal with 10 g of [1-(13)C]glucose to resolve direct/indirect pathways and galactose contributions to glycogen synthesis. Metabolite enrichments were determined by (2)H and (13)C nuclear magnetic resonance. In study 1, G6P-F6P exchange approached completion; therefore, the difference between position 2 and body water enrichments in study 2 (0.20% ± 0.03% vs 0.27% ± 0.03%, P < .005) was attributed to galactose glycogenesis. Dietary galactose contributed 19% ± 3% to glycogen synthesis. Of the remainder, 58% ± 5% was derived from the direct pathway and 22% ± 4% via the indirect pathway. The contribution of galactose to hepatic glycogen synthesis was resolved from that of direct and indirect pathways using a combination of (2)H(2)O and [1-(13)C]glucose tracers.

[Pituitary atypical adenoma or malignant corticotrophinoma?]

Pituitary tumors are classified into typical adenomas, atypical adenomas or carcinomas. Carcinoma represents 0.2% of pituitary tumors and is defined by the presence of metastases. It often presents as invasive and secreting macroadenoma, showing features of malignancy ab initio or over time. The high proliferative index (Ki-67) and immunostaining for p53 protein are common indicators of aggressiveness. We report a 58 years old male with invasive sellar incidentaloma. The hormonal study showed gonadal, thyroid, and somatotrophic failure, with increase of corticotropin (ACTH) and cortisol. Transsphenoidal surgery was performed and histology revealed a typical corticotrophinoma. The successive recurrences over 10 years led to five surgical reoperation and radiotherapy. After the third surgery, cellular atypia, Ki-67 of 27% and immunostaining for p53 were revealed. Subsequently, there were lesions suspicious of metastases (lung and lymph nodes), but the biopsy of the lymph nodes was inconclusive. The patient died before chemotherapy. In this case, the progressive loss of differentiation points to the need for early diagnosis, timely and aggressive treatment.

[Eating disorders and type 1 diabetes: about 4 clinical reports]

Type 1 Diabetes mellitus is a chronic disease, often diagnosed in youth and associated with important psychological, familial and social disorders. Its intensive treatment with insulin and dietary changes is an extra stress factor in a stage of life already complicated. This vulnerability, coupled with low self-esteem and psychological factors typical of the youth, makes eating disorders twice as common in young girls with type 1 diabetes. The omission of insulin is the sole purging behavior used to lose weight, culminating in a poor glycemic control and increased acute and chronic complications. The treatment seeks to achieve specific objectives, depending on the associated psychiatric pathology. Because of its frequency, the clinician should be alert to early manifestations of this association. We present four clinical cases of young people with type 1 diabetes and eating disorders, which show the complexity of the approach and monitoring of these patients.

Hiperplasia congénita da suprarenal de expressão tardia por deficiência de 21-hidroxilase: revisão da literatura e estudo genético preconcepção de cinco casais

The deficiency of the enzyme 21-hydroxylase (21-HO) is responsible for about 90% to 95% of all cases of congenital adrenal hyperplasia (HCSR). This disorder is one of the most frequent hereditary illnesses of autosomal recessive trait. The illness can be presented in two clinical forms: 1 - classic, subdivided in saltwasting form and simple virilizing form; 2 - nonclassic or late-onset. The severity of the illness is correlated with the degree of enzymatic activity of 21-HO, which depends on the type of mutation that occurs in gene CYP21A2. The late onset congenital adrenal hyperplasia is that one where the enzymatic blockade is less intense. The clinical is variable: precocious pubarche, polycystic ovaries, hirsutism, oligoamenorrhea, acne and infertility. Gold standard for the diagnosis of late onset congenital adrenal hyperplasia consists on the test of the tetracosactide, considering itself diagnostic positive when 17-hidroxiprogesterona (17-OHP) is higher of 10-15 ng per mL. Many patients don't need treatment; however, if necessary, such a treatment essentially consists on the Administration of glucocorticoids and antiandrogens. Considering that affected individuals and the carriers may have a severe mutation in CYP21A2, they can have descendents with the classic form (if their partner is also a carrier of a severe mutation), it is mandatory the genetic study of the couple. The authors illustrate the importance of this genetic study through five clinical cases, whose common link is the desire to have children, as well as the presence on the feminine element of late onset congenital adrenal hyperplasia. The genetic study of the couple allows adequate pre-conception counseling and also prevents the use of corticoids throughout the pregnancy (if there's no risk of descendents being affected with the classic form). This aspect must be had in account in programming the pregnancy, in order to prevent therapeutics and unnecessary distrusts.

[Late onset congenital adrenal hyperplasia due to 21-hydroxylase deficiency: revision of literature and preconception genetic study of five couples]

The deficiency of the enzyme 21-hydroxylase (21-HO) is responsible for about 90% to 95% of all cases of congenital adrenal hyperplasia (HCSR). This disorder is one of the most frequent hereditary illnesses of autosomal recessive trait. The illness can be presented in two clinical forms: 1 - classic, subdivided in saltwasting form and simple virilizing form; 2 - nonclassic or late-onset. The severity of the illness is correlated with the degree of enzymatic activity of 21-HO, which depends on the type of mutation that occurs in gene CYP21A2. The late onset congenital adrenal hyperplasia is that one where the enzymatic blockade is less intense. The clinical is variable: precocious pubarche, polycystic ovaries, hirsutism, oligoamenorrhea, acne and infertility. Gold standard for the diagnosis of late onset congenital adrenal hyperplasia consists on the test of the tetracosactide, considering itself diagnostic positive when 17-hidroxiprogesterona (17-OHP) is higher of 10-15 ng per mL. Many patients don't need treatment; however, if necessary, such a treatment essentially consists on the Administration of glucocorticoids and antiandrogens. Considering that affected individuals and the carriers may have a severe mutation in CYP21A2, they can have descendents with the classic form (if their partner is also a carrier of a severe mutation), it is mandatory the genetic study of the couple. The authors illustrate the importance of this genetic study through five clinical cases, whose common link is the desire to have children, as well as the presence on the feminine element of late onset congenital adrenal hyperplasia. The genetic study of the couple allows adequate pre-conception counseling and also prevents the use of corticoids throughout the pregnancy (if there's no risk of descendents being affected with the classic form). This aspect must be had in account in programming the pregnancy, in order to prevent therapeutics and unnecessary distrusts.

Sources of hepatic glycogen synthesis during an oral glucose tolerance test: Effect of transaldolase exchange on flux estimates

Sources of hepatic glycogen synthesis during an oral glucose tolerance test were evaluated in six healthy subjects by enrichment of a 75-g glucose load with 6.67% [U-(13)C]glucose and 3.33% [U-(2)H(7)]glucose and analysis of plasma glucose and hepatic uridine diphosphate-glucose enrichments (sampled as urinary menthol glucuronide) by (2)H and (13)C nuclear magnetic resonance. The direct pathway contribution, as estimated from the dilution of [U-(13)C]glucose between plasma glucose and glucuronide, was unexpectedly low (36 +/- 5%). With [U-(2)H(7)]glucose, direct pathway estimates based on the dilution of position 3 (2)H-enrichment between plasma glucose and glucuronide were significantly higher (51 +/- 6%, P = 0.05). These differences reflect the exchange of the carbon 4, 5, and 6 moiety of fructose-6-phosphate and glyceraldehyde-3-phosphate catalyzed by transaldolase. As further evidence of this exchange, (2)H-enrichments in glucuronide positions 4 and 5 were inferior to those of position 3. From the difference in glucuronide positions 5 and 3 enrichments, the fraction of direct pathway carbons that experienced transaldolase exchange was estimated at 21 +/- 4%. In conclusion, the direct pathway contributes only half of hepatic glycogen synthesis during an oral glucose tolerance test. Glucose tracers labeled in positions 4, 5, or 6 will give significant underestimates of direct pathway activity because of transaldolase exchange.

[Recurrent hypercortisolism after removal of an ACTH secretor pituitary adenoma associated with an adrenal macronodule]

A 29 years old patient was sent to our Outpatient Clinic of Endocrinology presenting clinic of hypercortisolism. Laboratorial study: High urinary free cortisol (UFC); serum cortisol - 25 microg/dl (8 am) (5-25) and 20 microg/dL (11pm); ACTH - 20 pg/mL (9-52) (8 am) and 14 pg/mL (11 pm); serum cortisol after dexamethasone suppression test: 14,9 mg/dL; CRH test: elevation of ACTH; Pituitary MRI: microadenoma; abdominal CT: nodule on the left adrenal. During inferior petrosal sinus sampling with CRH stimulation, ACTH reached 368 pg/mL on the right and 136 pg/mL on the left side. The patient was submitted to transsphenoidal surgery. After surgery, hypertension and physical stigmata improved. In 2006, a relapse of Cushing syndrome was suspected due to worsening of hypertension and increase of weight. A slight increase of UFC, undetectable ACTH and serum cortisol after dexamethasone suppression test equal to 16 microg/dL were found. On abdominal CT, the adrenal nodule kept the same characteristics. In December 2006, the patient was submitted to left adrenalectomy. After surgery, blood pressure normalized, UFC and serum cortisol were reduced, needing substitutive therapy. Progressive tapering of hydrocortisone doses lead to discontinuation in March 2007. He is clinically well, without any treatment. This is an unusual case, in which after surgical cure of Cushing disease, secretory autonomy of a coexisting adrenal nodule occurred. This clinical case is relevant, pointing out the complexity of hypercortisolism cases and the need of long follow-up.

A randomized double-blind study comparing the efficacy and safety of orlistat versus placebo in obese patients with mild to moderate hypercholesterolemia

INTRODUCTION

Obesity is a chronic disease and a serious health problem that leads to increased prevalence of diabetes, hypertension, dyslipidemia and gallbladder disease.

OBJECTIVE

To evaluate the efficacy of orlistat for weight loss and improved lipid profile compared to placebo in obese patients with hypercholesterolemia, treated over a period of 6 months.

METHODOLOGY

In a 6-month, multicenter (10 centers in Portugal), double-blind, parallel, placebo-controlled study, 166 patients, aged 18-65 years, body mass index (BMI) > or = 27 kg/m2, LDL cholesterol > 155 mg/dl, were randomized to a reduced calorie diet (600 kcal/day deficit) plus orlistat three times a day or placebo. Exclusion criteria included triglycerides > 400 mg/dl, severe cardiovascular disease, uncontrolled hypertension, type 1 or 2 diabetes under pharmacological treatment, and gastrointestinal or pancreatic disease.

RESULTS

The mean difference in weight from baseline was 5.9% (5.6 kg) in the orlistat group vs. 2.3% (2.2 kg) in the placebo group. In the orlistat group 49% of patients achieved 5-10% weight loss and 8.8% achieved > 10%. The orlistat group showed a significant reduction in total and LDL cholesterol, with similar changes for HDL in both treatment groups. The frequency of gastrointestinal adverse events was slightly higher in the orlistat group than in the placebo group, leading to discontinuation in 7 patients.

CONCLUSION

Treatment with orlistat plus a reduced calorie diet for 6 months achieved significant reductions in weight, BMI and lipid parameters.

Efficacy of the liposome trifluralin in the treatment of experimental canine leishmaniosis

Liposomes are used as carriers to deliver drugs and to treat diseases where infection is localised in the mononuclear phagocyte system cells, as is the case of leishmaniosis. Trifluralin is a dinitroaniline with proved anti-Leishmania activity in vitro. The efficacy of liposomal trifluralin (LIP/TFL) was studied in the treatment of experimental canine leishmaniosis through quantification of parasite burden using the limiting dilution assay, follow-up of anti-Leishmania antibodies by indirect fluorescent immunoassay and cytokine expression by Reverse Transcriptase-PCR, in the bone marrow, lymph nodes, skin and peripheral blood mononuclear cells in 5 female beagle dogs. After treatment, dogs showed a general remission of clinical signs related to parasite burden reduction and Th1 cytokine mRNA expression, but there was no significant decrease in antibody levels. Alternative treatment schemes with LIP/TFL are necessary to achieve optimal results.

Combined GSTM1 and GSTT1 null genotypes are associated with a lower risk of papillary thyroid cancer

Individual susceptibility to cancer is influenced by polymorphisms of genes encoding drug-metabolizing enzymes such as the glutathione S-transferases (GST). The null polymorphisms of the GSTM1 and GSTT1 genes have been associated to a modified risk of several cancers but studies of thyroid cancer have produced conflicting results. The aim of this study was to investigate the relationship between these polymorphisms and the risk of papillary thyroid cancer (PTC). A total of 188 patients with PTC and 247 controls were genotyped using a PCR-based assay. Odds ratios (OR) and 95% confidence intervals (CI) for each homozygous null genotype were determined. The frequency of each of the GSTM1 and GSTT1 null genotypes did not differ significantly between patients and controls (OR=0.83, 95%CI: 0.56-1.21; p=0.328; and OR=0.66, 95%CI: 0.39-1.12; p=0.123, respectively), but the frequency of individuals that had the combined GSTM1 null/GSTT1 null genotypes was significantly lower in the patient group (OR=0.50, 95%CI: 0.26-0.97; p=0.040). The GSTM1 null genotype was associated with a lower risk of advanced cancer stages (III/IV) (OR=0.50, 95%CI: 0.26-0.96; p=0.036) and the GSTT1 null genotype was associated with a lower risk of the follicular variant of PTC (OR=0.31, 95%CI: 0.10-0.97; p=0.044). These results suggest that GSTM1 and GSTT1 null genotypes are weak, yet possible, modifiers of the risk of PTC. This protective effect may be due to a role of the GSTM1 and GSTT1 encoded enzymes in the metabolic activation of putative thyroid carcinogens or in other pathways involved in thyroid carcinogenesis.

Genetic polymorphism of CYP2D6 influences susceptibility to papillary thyroid cancer

OBJECTIVE

Xenobiotic-metabolizing enzymes are widely polymorphic and confer interindividual variation in the ability to detoxify carcinogens or to activate pro-carcinogens. A common polymorphism of cytochrome P450 2D6 (CYP2D6) results in lack of enzyme activity and has been associated with an altered susceptibility to several cancers. The aim of this study was to investigate the association between the CYP2D6 poor metaboliser genotype and the risk of papillary thyroid cancer (PTC).

DESIGN

Retrospective case-control study.

PATIENTS

One hundred and eighty-seven patients with PTC and 256 controls.

MEASUREMENTS

Genotyping was performed by PCR and restriction enzyme analysis to detect the presence of the common CYP2D6*4 poor metaboliser allele.

RESULTS

The frequency of individuals with the homozygous poor metaboliser genotype was lower in the patient group [1.6 vs. 5.5%, P = 0.037, OR = 0.28 (95% CI 0.09-0.93)]. The CYP2D6*4 allele frequency was also lower in the patient group [13.4 vs. 21.7%, P = 0.002, OR = 0.56 (95% CI 0.39-0.80)].

CONCLUSIONS

The results suggest that the poor metaboliser genotype is associated with a protective effect against PTC. This could be explained by a possible role of CYP2D6 on the metabolic activation of putative environmental chemical thyroid carcinogens or by linkage to another cancer-causing gene. Further research may allow the identification of metabolic risk factors and contribute towards understanding the molecular mechanisms involved in thyroid carcinogenesis.

[Thyroid lymphoma]

Thyroid Lymphomas are rare tumors among thyroid neoplasms. Almost all types originate from B cells and the most frequent subtype is a diffuse large cell lymphoma. The majority arise in a background of Hashimoto's thyroiditis and patients present with a thyroid mass, rapidly enlarging and with pressure symptoms. The treatment depends on the histological subtype and stage of the disease but include radiotherapy and/or chemotherapy. The prognosis usually is favorable. The reported case presents a thyroid lymphoma. We discussed the clinic, diagnosis and treatment.

[Diabetic nephropathy: glomerular filtration rate and estimated creatinine clearance]

OBJECTIVE

To assess in diabetic nephropathy, the accuracy of estimated creatinine clearance (calculated with the Cockroft Gault formula) and the clearance of the Tc99m-DTPA, to measure the glomerular filtration rate (GFR).

PATIENTS AND METHODS

We analysed the GFR measure by Tc99m-DTPA method and the estimated by the Cockroft Gault formula, in 21 subjects with type 1 or type 2 diabetes.

RESULTS

There was a strong positive correlation between the two methods but the Cockroft Gault formula underestimated the GFR.

CONCLUSIONS

The formula gives a accurate estimates of GFR, when GFR is <100 ml/min/1,73 m2. Beside the underestimation, the formula could be used in the management of diabetic nephropathy because the repeated isotope assessments of renal function are impracticable.

Malignant teratoma of the thyroid: case report

Teratomas in the neck are rare neoplasms. Most of them occur in infants less than 1 year and are benign. In contrast, thyroid teratomas in adults are malignant and have fatal outcomes because of spread of tumor refractory to treatment. We report a case of a primary thyroid malignant teratoma in a 37-year-old woman. She was treated successfully with a combination of surgery, postoperative cis-platinum-based chemotherapy, and radiation therapy to the neck. Although the time of follow-up is short (24 months), we attribute her successful outcome to the use of this intensive therapeutic approach.

PROP1 gene analysis in Portuguese patients with combined pituitary hormone deficiency

OBJECTIVE

Mutations of the PROP1 gene lead to combined pituitary hormone deficiency (CPHD), which is characterized by a deficiency of GH, TSH, LH/FSH, PRL and, less frequently, ACTH. This study was undertaken to investigate the molecular defect in a cohort of patients with CPHD.

DESIGN, PATIENTS AND MEASUREMENTS

A multicentric study involving 46 cases of CPHD (17 familial cases belonging to seven kindreds and 29 sporadic cases) selected on the basis of clinical and hormonal evidence of GH deficiency, central hypothyroidism and hypogonadotrophic hypogonadism, in the absence of an identified cause of hypopituitarism. Mutations of PROP1 were investigated by DNA sequencing. Clinical, hormonal and neuroradiological data were collected at each centre.

RESULTS

PROP1 mutations were identified in all familial cases: five kindreds presented a c. 301-302delAG mutation, one kindred presented a c. 358C --> T (R120C) mutation and one presented a previously unreported initiation codon mutation, c. 2T --> C. Of the 29 sporadic cases, only two (6.9%) presented PROP1 germline mutations (c. 301-302delAG, in both). Phenotypic variability was observed among patients with the same mutations, particularly the presence and age of onset of hypocortisolism, the levels of PRL and the results of pituitary imaging. One patient presented a sellar mass that persisted into adulthood.

CONCLUSIONS

This is the first report of a mutation in the initiation codon of the PROP1 gene and this further expands the spectrum of known mutations responsible for CPHD. The low mutation frequency observed in sporadic cases may be due to the involvement of other unidentified acquired or genetic causes.

Noninvasive analysis of hepatic glycogen kinetics before and after breakfast with deuterated water and acetaminophen

The contributions of hepatic glycogenolysis to fasting glucose production and direct pathway to hepatic glycogen synthesis were quantified in eight type 1 diabetic patients and nine healthy control subjects by ingestion of (2)H(2)O and acetaminophen before breakfast followed by analysis of urinary water and acetaminophen glucuronide. After overnight fasting, enrichment of glucuronide position 5 relative to body water (G5/body water) was significantly higher in type 1 diabetic patients compared with control subjects, indicating a reduced contribution of glycogenolysis to glucose production (38 +/- 3 vs. 46 +/- 2%). Following breakfast, G5/body water was significantly higher in type 1 diabetic patients, indicating a smaller direct pathway contribution to glycogen synthesis (47 +/- 2 vs. 59 +/- 2%). Glucuronide hydrogen 2 enrichment (G2) was equivalent to body water during fasting (G2/body water 0.94 +/- 0.03 and 1.02 +/- 0.06 for control and type 1 diabetic subjects, respectively) but was significantly lower after breakfast (G2/body water 0.78 +/- 0.03 and 0.82 +/- 0.05 for control and type 1 diabetic subjects, respectively). The reduced postprandial G2 levels reflect incomplete glucose-6-phosphate-fructose-6-phosphate exchange or glycogen synthesis from dietary galactose. Unlike current measurements of human hepatic glycogen metabolism, the (2)H(2)O/acetaminophen assay does not require specialized on-site clinical equipment or personnel.

[Diabetes in the elderly: our reality]

AIM

To evaluate the impact of the aging of our population in the growing of diabetes prevalence, among patients treated inward at our department.

MATERIAL AND METHODS

The clinical files of 242 diabetics older than eighty years, treated between 1999 and 2002 were studied retrospectively. Demographic (sex, age, year of first contact), clinical (causes of admission, co-morbidities, duration of diabetes, previous hypoglycaemic treatment, duration of hospitalisation and evolution) and biochemical (glycaemia, HbA1c, lipaemia and C-peptide) data were recorded.

RESULTS

A progressive rising in the number of aged patients was found during this period (seven in 1999 to 55 in 2002), with a large proportion of women (73%). The more frequent causes of in-hospital treatment were hyperglycaemia (20.6%) and feet ulcers (septic or necrotic) (16.5%). In nearly 42% of the cohort an acute infection was found. Diabetes was unknown in 13% of cases and less than ten years of duration in 38%. In this cohort most of the patients (77%) were treated with oral hypoglycaemic drugs, mostly sulfonylureas. HbA1c mean value was 10.4 +/- 2.2%; C -peptide was measured in a subset of cases (n=79), suggesting deficient insulin secretion in 18% of them. The global mean duration of hospitalisation was eleven days. Nineteen patients (8%) died during the hospitalization.

CONCLUSIONS

In this study, we concluded that diabetes in people older than 75 years, is being progressively more often diagnosed. The general metabolic control was bad (HbA1c mean value--10.4 +/- 2.2%), with a significant number of patients presenting a deficient C-peptide secretion, worsened by frequent coexisting infections. So, a strengthened clinical care, directed to a careful diagnosis and treatment, may effectively contribute to a better prognosis and quality of life of aged diabetic patients.

[Friedreich ataxia and diabetes mellitus--family study]

Friedreich's ataxia (FA) is one of the genetic syndromes sometimes associated with diabetes and the most common hereditary ataxia. It is a autosomal recessive neurodegenerative disease, caused by a mutation in the FRDA gene, which originates decreased expression of frataxin, a mitochondrial protein involved in iron metabolism. The disorder is usually manifest in childhood and is characterised by ataxia, dysarthria, scoliosis and feet deformity. About two thirds of patients have hypertrophic cardiomyopathy, 10% have diabetes and 20% have another glucose homeostasis disorder. Both insulin resistance and beta-cell dysfunction are implicated in this patients' diabetes pathophysiology. The mean half-life is 35 years. Cause of death is usually related to cardiomyopathy or diabetes' complications. We report the case study of two twin sisters with 28 years old, in whom FA was diagnosed in the first decade, both of them with diabetes since their early twenties. A third sister with FA is reported, with no glucose homeostasis disorder. They also have two healthy male brothers. Based in this cases, the FA associated diabetes pathophysiology is discussed, concerning the therapeutic approach to these patients and to their diabetic relatives without neurologic symptoms. The role of molecular genetic testing and genetic counselling are also debated.

CYP2D6 genetic polymorphisms are associated with susceptibility to pituitary tumors

Several polymorphisms of drug-metabolizing enzymes have been implicated in the susceptibility to tumor development. The role of the CYP2D6, GSTM1 and GSTT1 genes has been extensively studied, with alleles conferring different metabolic efficiencies and tumor risk. We studied the relationship between the main polymorphisms of these genes and the susceptibility to develop pituitary tumors, by performing a case-control study comprising 235 patients and 256 controls which were genotyped by means of PCR-RFLP based assays. Frequencies of the CYP2D6*1 and of the poor metabolizer allele CYP2D6*4, were determined along with the frequencies of the GSTM1 and GSTT1 null genotypes. CYP2D6 genotype frequencies were similar in patients and controls (p=0.087). CYP2D6*1 and CYP2D6*4 allele frequencies were 83.8%, 16.2% in cases and 78.3%, 21.7% in controls, showing a significant difference between the two groups (p=0.012). There were no significant differences between the frequencies of the GSTM1 and GSTT1 null genotypes in both groups. No association was found between histological type and any of the studied polymorphisms. Our data suggest an association of the CYP2D6*1 allele and the susceptibility to pituitary adenomas, which could be due to an increased metabolism of unidentified procarcinogens or to linkage disequilibrium with another gene involved in pituitary tumorigenesis.

Simple measurement of gluconeogenesis by direct2H NMR analysis of menthol glucuronide enrichment from2H2O

The contribution of gluconeogenesis to fasting glucose production was determined by a simple measurement of urinary menthol glucuronide (MG) 2H enrichment from 2H2O. Following ingestion of 2H2O (0.5% body water) during an overnight fast and a pharmacological dose (400 mg) of a commercial peppermint oil preparation the next morning, 364 micromol MG was quantitatively recovered from a 2-h urine collection by ether extraction and a 125 micromol portion was directly analyzed by 2H NMR. The glucuronide 2H-signals were fully resolved and their relative intensities matched those of the monoacetone glucose derivative. The pharmacokinetics and yields of urinary MG after ingestion of 400 mg peppermint oil as either gelatin or enteric-coated capsules 1 h before breakfast were quantified in five healthy subjects. Gelatin capsules yielded 197 +/- 81 micromol of MG from the initial 2-h urine collection while enteric-coated capsules gave 238 +/- 84 micromol MG from the 2- to 4-h urine collection.

Platelet hyperactivation in maintained growth hormone-deficient childhood patients after therapy withdrawal as a putative earlier marker of increased cardiovascular risk

GH deficiency (GHD) is associated with a higher risk of vascular disease, whose pathophysiological mechanisms remains not yet fully elucidated. This study aimed to assess the main cardiovascular risk indexes, plasma catecholamines content, and the platelet function in childhood-onset GHD patients. Some of the main clinical examinations related with cardiovascular risk, plasma catecholamines content, as well as platelet intracellular free calcium concentration ([Ca(2+)](i)), whole-blood aggregation, and morphology were evaluated in childhood-onset GHD patients treated with GH for a variable period and off GH therapy for at least 2 yr before entry into study and in sex-, age-, and body mass index-matched control groups. Among the patients, group 1 (GHD-1) has recovered GH levels after withdrawal, whereas group 2 (GHD-2) has remained GH deficient. Minor differences on the cardiovascular risk indexes were observed between the groups. Plasma catecholamine concentrations in the GHD groups did not statistically differ from the control group, but higher adrenaline content was observed in the GHD-2 group when compared with the GHD-1 one. Basal and thrombin-evoked [Ca(2+)](i) and platelet aggregation were identical between the GHD-1 group and the matched control. However, the GHD-2 group has increased thrombin-evoked [Ca(2+)](i) (297.0 +/- 15.7 Deltanmol/liter; P < 0.01), collagen, and ADP-induced platelet aggregation (33.3 +/- 4.3 and 12.5 +/- 2.1 Omega, respectively; P < 0.05) vs. the control-2 group (Delta[Ca(2+)](i): 102.1 +/- 13.6 Deltanmol/liter; aggregation: 19.6 +/- 2.9 and 6.2 +/- 0.8 Omega). The platelet hyperreactivity state in the GHD-2 was reinforced by morphologic studies of electron microscopy. In conclusion, there were minor differences between the GHD-1 group and the controls, which might be due to the recovery of GH levels after therapy withdrawal. However, the maintained GHD group, despite minor cardiovascular risk index differences, has increased [Ca(2+)](i) and aggregation, which could indicate a hyperactivation state that might be viewed as an earlier marker of cardiovascular disturbances.

[ACTH-dependent Cushing's syndrome: a revision of 43 cases]

AIM

To evaluate the characteristics and outcomes of the patients diagnosed as ACTH-dependent Cushing syndrome, registered in the department.

MATERIAL AND METHODS

We reviewed the files of forty-three patients followed from 1974 to 2002.

RESULTS

A progressive rise in the number of patients diagnosed was found, being 80% females. Clinical suspicion was based mostly on the typical fat distribution; hirsutism and amenorrhoea were important in women. The more reliable diagnostic tests were: 11 pm cortisol, day curve of ACTH and cortisol, and dexamethasone suppression tests. The ACTH response to CRH during inferior petrosal sinus sampling permitted the diagnosis of ectopic source. In thirty-seven patients a pituitary adenoma was diagnosed. The three patients diagnosed before 1985 went for bilateral adrenalectomy (Nelson's syndrome in two); the others were submitted to transsphenoidal pituitary adenomectomy, obtaining remission in twenty six at the first operation and in two others at the second. Three patients had a recidive. Of the six patients with persistent disease (all treated with metyrapone or ketoconazole), three were submitted to radiotherapy, two to bilateral adrenalectomy, and one was waiting for surgery. Four patients had a bronchial carcinoid, successfully removed in three. One patient was lost to follow-up and another was still being evaluated.

CONCLUSIONS

We found a positive evolution in the capacity to diagnose and treat these patients. Neurosurgical ability to achieve remission was 80% in the operated cases. More effective technical methods and drugs, as well as a multidisciplinary and dedicated medical team, lead to long lasting remissions in most of the patients.

[Anaplastic thyroid tumor: retrospective analysis of 12 cases]

Anaplastic thyroid tumor is a rare tumor and constitutes 5 to 10% of thyroid carcinomas. Is one of the most aggressive solid tumors and the prognosis is always fatal with a mean survival of 3 to 7 months. The current therapeutics are scarce and inefficacious. A retrospective analysis was performed in 12 clinical cases of anaplastic thyroid tumor observed at the Department of Endocrinology, Diabetes and Metabolism of the University Hospital of Coimbra. We analysed data relative to sex, previous thyroid pathology, clinical signs and symptoms, date of diagnosis, treatment and outcome. In this series, the anaplastic thyroid carcinoma showed to be a highly malignant tumor with a mortality rate of 100% with a survival after the diagnosis between 15 days and 9 months.

[Fetal growth and glycemic control in type 1 diabetes pregnancy]

INTRODUCTION

Conflicting results have been reported with respect to the relationship between direct or indirect measures of glycemic control in mothers with type 1 diabetes and macrosomia.

OBJECTIVE

To evaluate the frequency of LGA babies in type 1 diabetic pregnancies and analyse the influence of some maternal characteristics and glucose control in oversized babies.

MATERIAL AND METHODS

A retrospective study of 18 pregnant women with type 1 diabetes mellitus was performed. It was divided in two groups: group 1 (G1- n=9)--pregnant women with LGA babies and group 2 (G2- n=9)--pregnant women with AGA (Appropriate weight for gestational age) babies. We evaluate the follow parameters: HbA1c in the third trimester of pregnancy, fasting and 1 h postprandial capillary glucose levels, pregestational BMI, maternal age, duration of Diabetes mellitus, weight gain during pregnancy, microvascular diabetes complications (retinopathy and nefropathy), and type of delivery. We defined LGA birth weight over the 90 centile.

RESULTS

LGA babies occurred in 50% of gestations. We did not find any statistical differences in maternal age, diabetes mellitus duration, pregestational BMI, weight gain during pregnancy, microvascular diabetes complications, HbA1c levels (medium value in the two groups 6,5%). The glucose fasting values were higher in G1: 95,7 +/- 31.7 mg/ dl, vs G2: 83.3 +/- 17.1 mg/dl without, however, reaching statistically significant differences. There was statically differences in postprandial glucose values G1: 160.3 +/- 60.2 mg/dl vs G2: 111.9 +/- 27.1 mg/dl -- p= 0.043.

CONCLUSIONS

The frequency of LGA babies was elevated 50% in type 1 diabetic pregnancies, although normal HbA1c values. Thus we conclude that the 1 h postprandial glucose levels should be considered a strong predictor of fetal growth.