The taste of D- and L-amino acids: In vitro binding assays with cloned human bitter (TAS2Rs) and sweet (TAS1R2/TAS1R3) receptors.

The taste of different enantiomeric forms of amino acids has been deeply investigated because it represents the most impressive case of correlation between stereochemistry and flavour. Herein, we aimed to elucidate the molecular activity of d- and l-amino acids using an in vitro system based on a cellular model overexpressing sweet and bitter receptors, and to analyse the correlation between in vitro and sensory studies. With our work we demonstrated specific enantiomeric activities for several amino acids on TAS1R2-TAS1R3 sweet receptor. Moreover, we proved interaction of tryptophan and phenylalanine with a specific group of TAS2Rs bitter receptors, confirming and improving the results recently obtained in the tasting of amino acids. In addition, we provide the first systematic analysis of l- and d-amino acid actions on the sweet heterodimeric receptor.

Analogues of perillaketone as highly potent agonists of TRPA1 channel.

Transient receptor potential (TRP) channels represent interesting molecular target structures involved in a number of different physiological and pathophysiological systems. In particular, TRPA1 channel is involved in nociception and in sensory perception of many pungent chemesthetic compounds, which are widespread in spices and food plants, including Perilla frutescens. A natural compound from P. frutescens (isoegomaketone) and 16 synthetic derivatives of perillaketone have been prepared and tested in vitro on rTRPA1 expressed in HEK293 cells and their potency, efficacy and desensibilisation activity measured. Most derivatives proved to be high potency agonists of TRPA1, with a potency higher than most natural agonists reported in the literature. These furylketones derivatives, represent a new class of chemical structures active on TRPA1 with many potential applications in the agrifood and pharmaceutical industry.

Completion thyroidectomy for differentiated thyroid cancer (results in a consecutive series of 68 patients).

INTRODUCTION: Completion thyroidectomy plays an important role in the management of patients with thyroid cancer. The aim of this study is to determine the indications for and timing of a second surgery, as well as surgical complications. MATERIAL AND METHODS: Operative reports, as well as the hospital and outpatient records of 686 consecutive patients, who had undergone surgery for differentiated thyroid cancer, were reviewed. Among these, 68 (9,9%) patient records of a completion thyroidectomy for cancer were analyzed. RESULTS: The mean time interval between the first and second operation was 3.6 months (range: 1-9). Post-operative complications occurred in 9 patients (12,9%). Among three patients with inferior laryngeal nerve palsy (4,4%) one had definitive palsy (1.4%). Hypoparathyroidism occurred in 6 patients (8,8%) being permanent in one of them (1.4%). No significant difference either for definitive inferior laryngeal nerve lesions (p = 0.9) or for definitive hypocalcemia (p = 1) was found between the groups of patients who had a completion thyroidectomy and those who had a one-step total thyroidectomy for cancer. CONCLUSIONS: Correct indications for re-operation, total lobectomy as a primary surgical procedure as well as lateral access to the residual thyroid gland could all reduce the high risks of complications related to this kind of surgery.

Contribution of germline mutations in the BRCA and PALB2 genes to pancreatic cancer in Italy.

Pancreatic adenocarcinoma (PC) is the third most common cancer associated with BRCA mutations. Most notice has been given to BRCA2, while the association between BRCA1 and PC is less widely reported. Recently, PALB2 has been implicated in both PC and breast cancer (BC) susceptibility. We selected 29 Italian PC patients from a case-control study of PC according to their personal and family history of both PC and breast/ovarian cancer (BC/OC) and tested them for presence of germline mutations in BRCA1, BRCA2 and PALB2. We identified no germline mutations or deletions in PALB2, but detected 7 BRCA mutations (4 in BRCA1 and 3 in BRCA2). These findings suggest that PALB2 does not play a major role in PC susceptibility in our population. As we found an almost equal frequency of germline mutations in BRCA1 and BRCA2, germline alterations in either of these genes may explain a subset of Italian families presenting both PC and BC/OC. Moreover, as we began the observation of these families from probands who are affected by PC, we provide here a direct assessment of the role of PALB2 and BRCA mutations in PC susceptibility.

Germline MLH1 and MSH2 mutations in Italian pancreatic cancer patients with suspected Lynch syndrome.

Lynch syndrome is an inherited cancer syndrome caused by germline mutations in mismatch repair (MMR) genes MLH1, MSH2, MSH6 and PMS2. LS predisposes to high risk of early-onset colorectal, endometrial and other tumors. Patients with Lynch syndrome have also been shown to have an elevated risk for pancreatic cancer (PC). In this study, we aimed to estimate the frequency of suspected Lynch syndrome among a series of 135 PC patients. Further, we wanted to determine the frequency of MMR gene mutations in the suspected Lynch syndrome cases. We also aimed to verify the pathogenicity of any novel non-truncating variants we might detect with a functional assay. Based on personal and/or familial cancer history, 19 patients were classified as suspected Lynch syndrome cases. DNA material for mutation analysis was available for eleven of them. Four patients were found to carry a total of five MLH1 or MSH2 variants. Of these, MSH2-Q402X, MSH2-G322D, and MLH1-K618A had been previously reported, while the MSH2-E205Q and MSH2-V367I variants were novel. MSH2-Q402X is a known stop mutation and reported here for the first time here in association with PC. MLH1-K618A was found in the unaffected branch of a kindred, suggesting that it may be a polymorphism or a low penetrance variant. MSH2-G322D likely does not cause a MMR defect, although this variant has also been associated with breast cancer as indeed seen in our patient. The novel variants MSH2-E205Q and MSH2-V367I were found in the same patient. Both novel variants were however functional in the applied MMR assay. Our findings suggest that only a small subset of pancreatic cancer patients carry pathogenic MMR mutations.

Non-antigen-specific CD8(+) T suppressor lymphocytes in diseases characterized by chronic immune responses and inflammation.

Recent studies on regulatory lymphocytes demonstrate that CD8(+) T suppressor (Ts) cells may have great relevance in controlling immune system homeostasis and avoiding development of chronic inflammatory diseases. Among the three subpopulations of CD8(+) Ts cells so far recognized in humans, the type 2 (non-antigen-specific) cell is characterized by the capacity to inhibit both T cell proliferation and cytotoxic T lymphocyte activity through secretion of soluble factors. Previous work has shown the impairment of in vitro generation of type 2 CD8(+) Ts cells from the peripheral blood of relapsed patients with multiple sclerosis, systemic lupus erythematosus, or systemic sclerosis. Here, similar findings are demonstrated for patients with human immunodeficiency virus or chronic hepatitis C virus infection. Furthermore, the presence of type 2 CD8(+) Ts cells infiltrating diseased tissues in patients with autoimmune thyroiditis or cancer is shown. Collectively, these findings suggest that type 2 CD8(+) Ts cells may be involved in the control of pathologic chronic immune responses, contributing in some cases to the pathogenesis of the disease.

[Artificial nutrition in inflammatory bowel disease]. / La nutrizione artificiale nelle malattie infiammatorie intestinali.

Malnutrition is often a major clinical problem in patients affected by IBD. Assessment of nutritional status should be routinely carried out in these patients and, in case of severe malnutrition, artificial nutrition should be used. In ulcerative colitis and in Crohn disease localized to colonic segments both Parenteral Nutrition (PN) and Enteral Nutrition (EN) have similar results as support treatments but they have no primary therapeutic effects and then they are indicated only in case of severe malnutrition and/or when a surgical procedure is planned. Some theoretical advantages derived from supplementation of short chain fatty acids and omega3-series is still debated. More evident are the advantages of nutritional support in Crohn enteritis. Both PN and EN have a role as a primary therapy capable to induce remission although these results are not prolonged in time when nutrition is not associated with pharmacological treatments. Experiments of pharmaco-nutrition with glutamine and fish fatty acid have to be validated in the clinical practice. In case of integrity of the small bowel and tolerance of the patient, EN is preferable to PN for its lower costs and reduced related complications. PN is still indicated in more severe cases or in acute phase when the need of restoring rapidly the hydroelectrolitic and nitrogen/caloric balance prevails.

Doppler evaluation of intrathyroid arterial resistances during preoperative treatment with Lugol's iodide solution in patients with diffuse toxic goiter.

BACKGROUND: The aim of this study was to ascertain the utility of echo-Doppler in the analysis of the low resistance thyroid vascularization in diffuse toxic goiter (DTG), and the effectiveness of Lugol's solution (iodine-iodide solution) in patients undergoing thyroidectomy. STUDY DESIGN: Twenty-five patients with diffuse toxic goiter were evaluated and compared with 19 normal subjects. Patients were treated with increasing doses of Lugol's solution 2% for 7 days until a total dose of 75 mg of iodine was given. Echo-Doppler was performed on the last day of treatment, 12 hours before operation. RESULTS: Mean basal Doppler Resistance Index (RI) of intrathyroid arterial flow was significantly lower in patients with DTG compared with normal controls (0.4718 +/- 0.0625 versus 0.55 +/- 0.05, range: 0.472 to 0.643; p = 0.008). Moreover, the RI was significantly increased in patients with DTG after Lugol's solution (+16.46 +/- 10.22%, range: -2.59 to +39.97; p< 0.0005). CONCLUSIONS: Echo-Doppler RI allowed documenting lower arterial resistances within the thyroid gland in patients with DTG. The use of preoperative Lugol's solution therapy induces normalization of those changes for safer thyroidectomy.

The impact of antibiotic resistance on the efficacy of three 7-day regimens against Helicobacter pylori.

BACKGROUND: Antibiotic resistance affects the success of anti-Helicobacter pylori therapies and varies greatly from country to country. AIM: To compare the efficacy of three short-term triple regimens in relation to H. pylori primary resistance in our region. METHODS: We enrolled 210 H. pylori-positive dyspeptic patients for this randomized, open, parallel-group study. Three arms of 70 patients each received the following 1-week regimens: (1) ranitidine bismuth citrate 400 mg b.d. + clarithromycin 250 mg b.d. + metronidazole 500 mg b.d. (RCM); (2) bismuth subcitrate 240 mg b.d. + amoxycillin 1000 mg b.d. + metronidazole 500 mg b.d. (BAM); (3) omeprazole 20 mg o.d. + clarithromycin 250 mg b.d. + metronidazole 500 mg b.d. (OCM). H. pylori was assessed by CLO-test and histology before and 4 weeks after therapy. Antibiotic resistance was assessed by E-test. RESULTS: On intention-to-treat analysis RCM was more effective than OCM (84% vs. 69%; P < 0.03) and BAM (84% vs. 63%; P < 0.004). MIC determination was successful in 117 out of 210 patients (55%); metronidazole resistance was present in 52 out of 117 patients (44%) and clarithromycin resistance was present in 17 out of 117 patients (14%). Excellent cure rates were achieved when strains were sensitive to both antibiotics (100% with RCM and BAM and 90% with OCM), whereas RCM was superior to OCM (P=0.009) and BAM (P=0.001) with respect to overall resistant strains (94% vs. 57% and 38%, respectively). CONCLUSIONS: One-week RCM is the best regimen to eradicate H. pylori in our geographical area. This seems to be linked to the better ability of RCM compared to OCM and BAM in overcoming the high prevalence of H. pylori resistance to both metronidazole and clarithromycin in our region.

Cervico-mediastinal extension of thyroid cancer.

A surgical series of 30 cervico-mediastinal thyroid cancer patients operated on has been retrospectively reviewed. Results were compared with those obtained in patients operated on for benign cervico-mediastinal goiter and thyroid cancer confined to cervical region. Of 4688 thyroidectomies performed, 30 patients were operated on for thyroid carcinoma with cervico-mediastinal extension. There were 15 males and 15 females. The mean age was 67 years (range, 21-86 years). Patients with cervico-mediastinal cancer were significantly older than patients with benign cervico-mediastinal goiter (P < 0.0001). Time between onset of first symptoms and surgery was significantly longer in patients with cervico-mediastinal cancer than in those with benign cervico-mediastinal goiter (P < 0.0001) and cervical thyroid cancer. Signs and symptoms at the time of surgery were cervical mass in 28 patients (93%), cervical lymphadenopathy in 20 patients (66%), dyspnea in 21 (70%), dysphagia in 9 (30%), dysphonia in 2 (7%), and venous stasis in 1 (3%). None of the patients was asymptomatic. Total thyroidectomy with functional lymphectomy was performed in 16 cases. Seven of these patients were operated on in 2 stages. In 8 cases the operation was a debulking procedure, and in 6 it was a near-total thyroidectomy. Sternotomy was performed in two cases. A differentiated thyroid cancer was found in 21 patients (70%), medullary in 5 (17%) and undifferentiated in 4 (13%). The incidence of medullary carcinoma was significantly higher compared with cervical cancer (P < 0.008). Postoperative complications were higher than those occurring in benign cervico-mediastinal goiter and similar to those occurring in cervical cancer. The actuarial survival was similar to that of cervical cancer matched for age and sex. This analysis shows that the longer clinical history of goiter is related to its endothoracic development and its neoplastic transformation. This finding should further encourage surgeons to treat any cervico-mediastinal goiter as promptly as possible.

Goiter recurrence in patients submitted to thyroid-stimulating hormone suppression: possible role of insulin-like growth factors and insulin-like growth factor-binding proteins.

BACKGROUND: It is known that factors other than thyroid-stimulating hormone, such as insulin-like growth factor-I (IGF-I) and epidermal growth factor, have a goitrogenic effect. It has been established that insulin-like growth factor-binding proteins (IGFBPs) may play a role as autocrine/paracrine factors in regulating the local actions of IGFs. Both an inhibitory and a stimulatory effect for different IGFBPs have been shown in several cell systems. The aim of this study was to assess the involvement of IGFBPs in the goitrogenic process in patients with goiter recurrence. METHODS: The IGFBP-1 and -3 content in normal and nodular tissues obtained at the time of thyroidectomy from 10 patients with recurrent goiters, unresponsive to thyroid-stimulating hormone suppressive therapy, was studied. In all patients, a fragment of normal tissue was also obtained. The IGF-I, IGFBP-1, and -3 content was evaluated by specific immunoassays and/or immunoblotting with anti-IGFBP specific antiserum. RESULTS: The IGF-I content was significantly higher (P < .05) in nodular tissues (8.0 +/- 1.6 ng/g of tissue) than what was found in normal tissue (4.8 +/- 0.9 ng/g). Radioimmunoassay IGFBP-3 concentration in nodular tissue was 111.5 +/- 18.2 ng/g significantly higher (P < .001) than values found in normal tissue (77.5 +/- 18.6 ng/g). By immunoblot, IGFBP-1 appeared higher in all but 1 nodular tissue. CONCLUSIONS: These data raise the possibility that IGFBPs are important in the proliferative activities entailed in the goitrogenic process. Three mechanisms are potentially involved: (1) reduction of the potency of locally produced IGF peptide to downregulate type I receptors (potentiating effect on the autocrine/paracrine mitogenic action of IGFs); (2) increase of the IGF-I tissue concentration restraining its passage to circulation; and (3) protection of IGF-I from degradation. Further studies are needed to define a more precise link between these factors and the recurrence of goiter.

Pseudotumor of the liver: a challenging diagnosis.

Inflammatory pseudotumors of the liver are rare, and their natural history is mostly unknown. Making the diagnosis is often difficult, and these masses are often confused with other lesions, generally either primary or secondary neoplasms. The case of a patient who had an exhaustive preoperative work-up, including ultrasonography, CT scan and MRI, is herein presented. The characteristics of each exam, particularly those of the MRI, in which the pattern is poorly described in the literature, are reported. A fine needle biopsy was not contributive, as it was performed too centrally within the nodule. Only a high degree of suspicion and the existence of this tumor might lead to a preoperative diagnosis, thus avoiding major surgery. However, as is evident from the experiences of most authors and from our own, doubt may persist even after an exhaustive work-up. Since the morbidity and mortality of liver resection of noncirrhotic livers is low, surgery should be considered the treatment of choice.

[Treatment of hepatic recurrence after resection of hepatocellular carcinomas]. / Traitement des récidives hépatiques après résection des carcinomes hépatocellulaires.

Between October 1990 and December 1995, 86 patients underwent hepatic resection for hepatocellular carcinoma (HCC). All resections were carried out with the aim of achieving complete cure. Fifty one (60%) of these patients subsequently developed recurrent HCC. Only twenty patients could be treated in our hospital. There were 18 men and 2 women, with a mean age of 61 years at the time of recurrence. Six patients had a normal liver. Fourteen patients had associated liver cirrhosis. using Pugh's classification, 7 patients were Pugh A, 6 Pugh B and 1 Pugh C. The initial hepatic resection had consisted of major hepatectomy in 9 cases and segmentectomy in the remaining 11 patients. The mean time to recurrence was 17 months. There were 3 recurrences on the resection margin and 17 recurrences away from the hepatic stump. The therapeutic choice after hepatic recurrence was based on the number of tumors, hepatic function and the size of the liver remnant. Six patients were treated by tamoxifen due to poor hepatic function; median survival after recurrence was 6 months. Four patients with a single recurrent tumor on an atrophied liver remnant were treated by percutaneous ethanol injection with a median survival after recurrence of 15 months. Five patients with multiple diffuse lesions and good hepatic function were treated by transarterial chemoembolisation with a median survival after recurrence of 30 months. Five patients with a solitary tumor and good hepatic function underwent a second hepatic resection with a median survival after recurrence of 35 months. The overall median survival after diagnosis of recurrence was 20 months. These results suggest that an active treatment should be carried out in cases of recurrence of HCC. A second resection, if technically possible, offers the best chance of survival.

Is euthyroidism the goal of surgical treatment of diffuse toxic goitre?

OBJECTIVE: To find out by studying a homogeneous group of patients whether euthyroidism is achievable by surgical treatment of diffuse toxic goitre. DESIGN: Retrospective study. SETTING: Teaching hospital, Italy. SUBJECTS: 128 of the 152 patients operated on for diffuse toxic goitre during the period January 1971-December 1994 and followed up for a median of 83 months (range 6-289). INTERVENTION. Standard subtotal thyroidectomy. MAIN OUTCOME MEASURES: Operative mortality, recurrence, hypothyroidism and late complications. RESULTS: There were no operative deaths. After 10 years follow up, 11 patients (9%) had developed recurrences and 61 (48%) were euthyroid. In the univariate analysis the risk of hypothyroidism was significantly associated with the year of operation (p = 0.04), the duration of symptoms (p < 0.01), and the degree of lymphocytic infiltration (p < 0.01). The last two were confirmed by multivariate analysis. CONCLUSION: Subtotal thyroidectomy seems to be an effective treatment of diffuse toxic goitre as a stable euthyroid state can be achieved in nearly half the patients after a prolonged follow up.

Mucoepidermoid carcinoma of the thyroid gland arising from a papillary epithelial neoplasm.

We report a case of mucoepidermoid carcinoma of the thyroid gland. The simultaneous association of papillary and mucoepidermoid carcinoma in a Hashimoto's thyroiditis makes the present observation unusual. Surgery was limited due to local extension of the neoplasm. The patient consequently underwent external radiotherapy followed by radiometabolic therapy. The patient survived 11 months after diagnosis. As far as the histogenesis of the neoplasm is concerned, we believe that mucoepidermoid areas correspond to squamous and mucinous metaplasia of a preexisting papillary carcinoma. Transition areas between elements morphologically characteristic of both neoplasms were observed. Histochemical and immunohistochemical studies confirmed the diagnosis of a carcinoma with multiple aspects showing a focal positive reaction for thyroglobulin or keratin antisera. Therefore, this demonstrates different functional activities of the neoplastic cells. There is still debate about adjuvant therapies, the results of which appear for the moment very poor.

Toxic thyroid adenoma: absence of DNA mutations of the TSH receptor and Gs alpha.

DNA point mutations of the TSH receptor and of the alpha subunit of the stimulatory GTP-binding protein (Gs alpha) have been suggested as major causes of hyperfunctioning thyroid adenomas. However, significant differences in the prevalence of these mutations (from 0.3 to 84%) have been found in different populations. The present study was designed to evaluate further the presence of mutations in discrete fragments of cDNA encoding critical regions of the TSH receptor and of the Gs alpha involved in signal transduction and cAMP production. Genomic DNA extracted from 15 thyroid adenomas and surrounding quiescent thyroid tissues was used as a template to amplify four DNA fragments of TSH receptor and one DNA fragment of Gs alpha. TSH receptor and Gs alpha DNAs were analyzed by a number of techniques. We did not detect any mutations (new or previously described) in our patients. These results confirm that the causes of solitary toxic adenomas are protean, and only some of them may be somatic DNA point mutations. Since the clinical features of solitary toxic adenoma are homogeneous, it could be important to establish the specific molecular defect underlying each case, in order to follow up the patients and to assess their clinical evolution.

[Lipiodol with and without Gelfoam in primary liver tumors. Plasma levels of Mitoxantrone and clinical results]. / Lipiodolizzazione associata o meno a Gelfoam in pazienti con tumore epatico primitivo. Livelli plasmatici di Mitoxantrone e risultati clinici.

Transcatheter chemoembolization with various drugs is employed for palliative treatment of hepatocellular carcinoma. Thirty-seven patients (33 with Child A or B cirrhosis) were treated with 14 mg/m2 of Mitoxantrone and up to 20 ml of Lipiodol, followed by Gelfoam embolization as indicated. Sixty-nine cycles were given, with mean (+/-SD) Lipiodol and emulsified Mitoxantrone doses of 11.3 +/- 3.8 ml and 11.8 +/- 5.2 mg, respectively. Thirteen, 16, and 8 patients received one, two, and three cycles, respectively, with time intervals of 123 +/- 60 days. Thirty patients had Gelfoam embolization at the first cycle, 9 at the second and 4 at the third. At the first cycle, 10 patients underwent serial measurements of serum Mitoxantrone up to two hours after a full dose of emulsified drug. Drug levels resulted much lower than those reported after plain arterial infusion, with AUC levels (+/-SE) of 5924 +/- 1015 and 4381 +/- 429 ng/ml x 120 min in 6 and 4 cases treated with and without Gelfoam, respectively. No treatment related deaths occurred. Complications were mild and transient, including nausea vomiting in most cases, fever > 38 degrees C 67%, pain 74%, ascites 8% jaundice 3%, bleeding 3%, pancreatitis 3%, myelosuppression 44%, diarrhea 5%. Treatment response rate was 49% (including 16% minor response) with 16% early progressions. With a median follow-up of 12 months, the 12-month response duration and survival rates were 56% and 79% respectively. Transcatheter chemoembolization with Mitoxantrone deserves further evaluation in randomized studies.

Preoperative predictors of blood transfusion in liver resection for tumor.

BACKGROUND: Hepatic resection remains a hemorrhagic procedure. The purpose of this study was to investigate the preoperative predictive factors of intraoperative blood transfusion. METHODS: One hundred consecutive patients who underwent hepatic resection for tumor were included in this retrospective study. Resection was performed for primary malignancies (n = 52), metastases (n = 18), and benign tumors (n = 30). Liver resection was performed under intermittent clamping of the portal triad. Seventeen variables were analyzed. RESULTS: The operative blood loss was 1,872 mL (mean 1,104; range 650 to 4500) for the 22 transfused patients. The mean blood transfusion was 5.5 units (mean 3.2; range 2 to 12) of packed red cells. Multivariate analysis demonstrated that the size of liver resection (P <0.001) and the prothrombin rate (P <0.001) were independently correlated with blood transfusion. CONCLUSIONS: Patients undergoing extended resection or with abnormal coagulation could be considered for autologous blood transfusion.

Laparoscopic cholecystectomy and gallbladder cancer: a diagnostic and therapeutic dilemma.

The correct treatment strategy of patients with unsuspected gallbladder cancer undergoing laparoscopy, and the prevention of delayed diagnosis are current issues. We report a case of late diagnosis with umbilical metastasis and poor survival. A policy of careful inspection of the gallbladder and a cautious strategy in the case of gross alteration of its external morphology seems advisable during laparoscopic cholecystectomy. Although no agreement exists concerning the best treatment in the event of delayed diagnosis, the adopted strategy is contingent on patient status, disease stage and the possibility of performing appropriate follow-up.