Schiff Base-Based Hydrogel Embedded with In Situ Generated Silver Nanoparticles Capped by a Hyaluronic Acid-Diethylenetriamine Derivative for Wound Healing Application

In this study, hydrogels were produced using a Schiff base reaction between two hyaluronic acid derivatives: one containing aldehyde groups (HA-Ald) and the other holding a diethylenetriamine with terminal amino groups (HA-DETA). The DETA portion promotes the in situ growth, complexation, and stabilization of silver nanoparticles (AgNPs), eliminating the need for external reducing agents. The reaction between HA-DETA and HA-Ald leads to the formation of imine bonds, which results in dynamically pH-responsive cross-linking. While the DETA capping ability helped in embedding the AgNPs, the on/off pH environmental responsivity of the hydrogel allows for a controlled and on-demand release of the drug, mainly when bacterial infections cause pH variation of the wound bed. The injectable hydrogels resulted in being highly compatible in contact with blood red cells, fibroblasts, and keratinocytes and capable of having a proliferative effect on an in vitro wound scratch model. The pH-responsive hydrogels showed proper antibacterial activity againstPseudomonas aeruginosaandStaphylococcus aureus, common bacterial strains presented in wound infections. Finally, in vivo wound model studies demonstrated an overall speeding up in the wound healing rate and advanced wound conditions in the experimental group treated with the hydrogels compared to control samples.

Sustainable soy protein microsponges for efficient removal of lead (II) from aqueous environments

Protein-based materials recently emerged as good candidates for water cleaning applications, due to the large availability of the constituent material, their biocompatibility and the ease of preparation. In this work, new adsorbent biomaterials were created from Soy Protein Isolate (SPI) in aqueous solution using a simple environmentally friendly procedure. Protein microsponge-like structures were produced and characterized by means of spectroscopy and fluorescence microscopy methods. The efficiency of these structures in removing lead (Pb²⁺) ions from aqueous solutions was evaluated by investigating the adsorption mechanisms. The molecular structure and, consequently, the physico-chemical properties of these aggregates can be readily tuned by selecting the pH of the solution during production. In particular, the presence of β-structures typical of amyloids as well as an environment characterized by a lower dielectric constant seem to enhance metal binding affinity revealing that hydrophobicity and water accessibility of the material are key features affecting the adsorption efficiency. Presented results provide new knowledge on how raw plant proteins can be valorised for the production of new biomaterials. This may offer extraordinary opportunities towards the design and production of new tailorable biosorbents which can also be exploited for several cycles of purification with minimal reduction in performance. SYNOPSIS: Innovative, sustainable plant-protein biomaterials with tunable properties are presented as green solution for water purification from lead (II) and the structure-function relationship is discussed.

Hydrocarbons removal from synthetic bilge water by adsorption onto biochars of dead Posidonia oceanica

Bilge waters are wastewaters produced on boats during navigation and usually contain hydrocarbons and oils. They cannot be directly released into the sea if not below a hydrocarbons concentration limit set by current legislation. Appropriate oil in water separator (OWS) systems can be installed on board boats to remove hydrocarbons from bilge water allowing their spillage into the sea. These systems may contain an adsorption step on a suitable adsorbent. Here, biochars produced from pyrolysis of dead Posidonia oceanica, pristine or chemically activated, have been tested as hydrocarbons adsorbents. Adsorption experiments with aqueous dispersions simulating bilge waters containing a marine gas oil (MGO) fuel for boats, a surfactant, and different NaCl concentrations were carrying out. The hydrocarbons concentrations before and after adsorption have been directly measured by using the reverse phase HPLC technique coupled with a fluorescence detector. These measurements are very fast and their reliability was verified by re-measuring the hydrocarbons concentrations of some samples with the GC-MS-MS technique, according to one of the traditional methods for hydrocarbons determination in emulsions. Different isotherm equations were used to fit the adsorption data. The biochars were characterized from the chemical-structural point of view by means of several instrumental techniques.

Lead(II) ions adsorption onto amyloid particulates: An in depth study

The production of new cost-effective biocompatible sorbent sustainable materials, with natural origins, able to remove heavy metals from water resources is nowadays highly desirable in order to reduce pollution and increase clean water availability. In this context, self-assembled protein materials with amyloid structures seem to have a great potential as natural platform for a broader development of highly-tunable structures. In this work we show how protein particulates, a generic form of protein aggregates, with spherical micro sized shape can be used as adsorbents of Pb²⁺ ions from aqueous solution. The effect of pH, ionic medium, ionic strength and temperature of the metal ion solution on the adsorption ability and affinity has been evaluated revealing the complexity of adsorption mechanisms which are the result of the balance of specific interactions with functional groups in protein structure and not specific ones common to all polypeptide chains, and possibly related to amyloid state and to modification of particulates hydration layer.

Evaluation of adsorption ability of cyclodextrin-calixarene nanosponges towards Pb2+ ion in aqueous solution

Different cyclodextrin-calixarene nanosponges (CyCaNSs) have been characterized by means of FFC-NMR relaxometry, and used as sorbents to remove Pb²⁺ ions from aqueous solutions. Considering that the removal treatments may involve polluted waters with different characteristics, the adsorption experiments were performed on solutions without and with the addition of background salts, under different operational conditions. The adsorption abilities and affinities of the nanosponges towards Pb²⁺ ions were investigated by measuring the metal ion concentration by means of Inductively Coupled Plasma Emission Spectroscopy (ICP-OES) and Differential Pulse Anodic Stripping Voltammetry (DP-ASV). The acid-base properties of nanosponges and of metal ion as well as their interactions with the other interacting components of the systems have been considered in the evaluation of adsorption mechanism. Recycling and reuse experiments on the most efficient adsorbents were also performed. On the grounds of the results obtained, post-modified CyCaNSs appear promising materials for designing environmental remediation devices.

8-Hydroxyquinoline-2-Carboxylic Acid as Possible Molybdophore: A Multi-Technique Approach to Define Its Chemical Speciation, Coordination and Sequestering Ability in Aqueous Solution

8-hydroxyquinoline-2-carboxylic acid (8-HQA) has been found in high concentrations (0.5–5.0 mmol·dm⁻³) in the gut of Noctuid larvae (and in a few other lepidopterans), in which it is proposed to act as a siderophore. Since it is known that many natural siderophores are also involved in the uptake and metabolism of other essential elements than iron, this study reports some results on the investigation of 8-HQA interactions with molybdate (MoO₄²⁻, i.e., the main molybdenum form in aqueous environments), in order to understand the possible role of this ligand as molybdophore. A multi-technique approach has been adopted, in order to derive a comprehensive set of information necessary to assess the chemical speciation of the 8-HQA/MoO₄²⁻ system, as well as the coordination behavior and the sequestering ability of 8-HQA towards molybdate. Chemical speciation studies have been performed in KCl_(aq) at I = 0.2 mol·dm⁻³ and T = 298.15 K by ISE-H⁺ (glass electrode) potentiometric and UV/Vis spectrophotometric titrations. CV (Cyclic Voltammetry), DP-ASV (Differential Pulse-Anodic Stripping Voltammetry), ESI-MS experiments and quantum mechanical calculations have been also performed to derive information about the nature and possible structure of species formed. These results are also compared with those reported for the 8-HQA/Fe³⁺ system in terms of chemical speciation and sequestering ability of 8-HQA.

Speciation Studies of Bifunctional 3-Hydroxy-4-Pyridinone Ligands in the Presence of Zn2+ at Different Ionic Strengths and Temperatures

The acid–base properties of two bifunctional 3-hydroxy-4-pyridinone ligands and their chelating capacity towards Zn²⁺, an essential bio-metal cation, were investigated in NaCl aqueous solutions by potentiometric, UV-Vis spectrophotometric, and ¹H NMR spectroscopic titrations, carried out at 0.15 ≤ I/mol ⁻¹ ≤ 1.00 and 288.15 ≤ T/K ≤ 310.15. A study at I = 0.15 mol L⁻¹ and T = 298.15 K was also performed for other three Zn²⁺/L^z− systems, with ligands belonging to the same family of compounds. The processing of experimental data allowed the determination of protonation and stability constants, which showed accordance with the data obtained from the different analytical techniques used, and with those reported in the literature for the same class of compounds. ESI-MS spectrometric measurements provided support for the formation of the different Zn²⁺/ligand species, while computational molecular simulations allowed information to be gained on the metal–ligand coordination. The dependence on ionic strength and the temperature of equilibrium constants were investigated by means of the extended Debye–Hückel model, the classical specific ion interaction theory, and the van’t Hoff equations, respectively.

A critical approach to the toxic metal ion removal by hazelnut and almond shells

The adsorption capacity of ground hazelnut (HS) and almond (AS) shells towards Pb(II) and Cd(II) has been studied at pH = 5, in NaNO₃ and NaCl ionic media, in the ionic strength range 0.05-0.5 mol L^-1. Kinetic and equilibrium experiments were carried out by using the Differential Pulse Anodic Stripping Voltammetry technique to check the amount of the metal ion removed by HS and AS materials. Different kinetic and equilibrium equations were used to fit experimental data and a statistical study was done to establish the suitable model for the data fitting. A speciation study of the metal ions in solution was also done in order to evaluate the influence of the ionic medium on the adsorption process. TGA-DSC, FT-IR, and SEM-EDX techniques were used to characterize the adsorbent materials. The mechanism of metal ions adsorption was explained on the basis of the results obtained by the metal ions speciation study and the characterization of materials.

Palladium nanoparticles immobilized on halloysite nanotubes covered by a multilayer network for catalytic applications

Halloysite nanotubes were functionalized with bis-vinyl imidazolium salts and PdNPs to obtain an efficient catalyst for fine chemical synthesis.

A novel thermodynamic approach for the complexation study of toxic metal cations by a landfill leachate

The leachate humic fraction is a good sequestering agent towards toxic metal ions, influencing their aqueous solution behaviour and their environmental impact.

Evaluation and comparison of trace metal accumulation in different tissues of potential bioindicator organisms: Macrobenthic filter feeders Styela plicata, Sabella spallanzanii, and Mytilus galloprovincialis

Trace metal concentrations were measured in different tissues of Sabella spallanzanii, Styela plicata, and Mytilus galloprovincialis collected in the Termini Imerese Harbor (Sicily, Italy) to evaluate the potential use of these species as bioindicators. Higher bioaccumulation factors (BAFs) were calculated in the tube of S. spallanzanii, except for As, which had a higher BAF in the branchial crown of the same species. Regarding the other species analyzed, higher BAFs were found in the digestive gland of M. galloprovincialis. An exception was Pb, which was significantly more concentrated in the branchial basket and tunic of S. plicata. The BAFs calculated in the present study show that all the species analyzed accumulate a certain amount of metals as a consequence of filter feeding mechanisms, and thus it was possible to assess the suitability of S. plicata, S. spallanzanii, and M. galloprovincialis as indicators of water quality. In particular, the tube of S. spallanzanii is an important compartment in terms of metal retention and is more suitable for the evaluation of contamination from trace elements. Environ Toxicol Chem 2016;35:3062-3070. © 2016 SETAC.

Pb(II) adsorption by a novel activated carbon - alginate composite material. A kinetic and equilibrium study

The adsorption capacity of an activated carbon - calcium alginate composite material (ACAA-Ca) has been tested with the aim of developing a new and more efficient adsorbent material to remove Pb(II) ion from aqueous solution. The study was carried out at pH=5, in NaCl medium and in the ionic strength range 0.1-0.75molL^-1. Differential Pulse Anodic Stripping Voltammetry (DP-ASV) technique was used to check the amount of Pb(II) ion removed during kinetic and equilibrium experiments. Different kinetic (pseudo first order, pseudo second order and Vermuelen) and equilibrium (Langmuir and Freundlich) models were used to fit experimental data, and were statistically compared. Calcium alginate (AA-Ca) improves the adsorption capacity (q_m) of active carbon (AC) in the ACAA-Ca adsorbent material (e.g., q_m=15.7 and 10.5mgg^-1 at I=0.25molL^-1, for ACAA-Ca and AC, respectively). SEM-EDX and thermogravimetric (TGA) measurements were carried out in order to characterize the composite material. The results of the speciation study on the Pb(II) solution and of the characterization of the ACAA-Ca and of the pristine AA-Ca and AC were evaluated in order to explain the specific contribution of AC and AA-Ca to the adsorption of the metal ion.

Coronary artery problems and disease in adults with congenital heart disease: how to evaluate, how to prevent, how to treat

There are a wide variety of coronary artery anomalies and disease in adults with congenital heart disease (CHD). In fact, the increasing burden of acquired coronary artery disease (CAD) has to be considered in addition to congenital abnormalities of the coronary arteries, isolated or associated to other congenital diseases. This is largely a consequence of the increasing number of patients reaching older age. Due to complex underlying cardiac anatomy, previous surgery and comorbidities, treatment can be challenging. Individualized and multidisciplinary management involving congenital heart cardiologists, cardiac surgeons, coronary interventionists and imaging specialists is essential. This review gives an overview of coronary artery involvement in adults with CHD, summarizes the current literature and focuses on prevention, diagnosis and treatment. The potential role of cardiovascular risk factors for CAD is also discussed.

Preoperative diagnosis of THYR 3 versus follicular lesion: malignant postoperative ratio

AIM

In the evaluation of nodular thyroid lesions, cytology is the main diagnostic instrument, associated with ultrasound examination.

METHODS

We prospectively categorized into a dedicated database, 612 patients submitted to thyroidectomy from January 2009 to December 2011. We selected two groups of patients: the cases with "follicular lesions" and the cases classified as "THYR 3" using Bethesda Classification.

RESULTS

Of 612 patients submitted to TT, in 68 cases, 8 males (M) and 60 females (F), we recorded a preoperative cytological diagnosis compatible with THYR 3 class. In 56 cases, 82.4% of the patients (5 M, 51 F), we performed a thyroidectomy with Conventional technique (CT) and in 12 cases, 12.6% of the patients (3M, 9F) with video-assisted technique (MIVAT). In 39 cases (57.1%) of the THYR 3 patients treated, a benign disease was found while in the other 29 cases (42.9%) a differentiated thyroid cancer (DTC) were found. In patients with nodules classified as "follicular proliferation", treated in the same period and by the same surgical team, we recorded 97 cases (79 F, 18 M). The patients were treated with TT in 72 cases, with MIVAT in 22 cases; in 3 cases we performed a HT with traditional technique. Adenomatous hyperplasia was found in 51; DTC was found in 21 cases and adenoma in 25 cases. The analysis of the incidence of benign versus malignant disease between the 2 groups showed a P<0.0001.

CONCLUSION

In our experience, we recommend surgery, TT or HT, for THYR 3 nodules analyzed for the first time by FNAB with sonographic pattern suspicious for malignancy.

Effect of physiological exercise on osteocalcin levels in subjects with adrenal incidentaloma

AIM

In the present study, we have evaluated whether physical exercise affect low osteocalcin concentrations observed in patients with subclinical hypercortisolism.

SUBJECTS AND METHODS

Sixteen patients (10 men and 6 women, age 38-55 yr) with adrenal incidentaloma were studied. Fifteen healthy volunteers matched for age (range 35-47 yr) were used as controls. Subjects were submitted to a 8-week exercise-training program with cycle-ergometer for 1 h/day 3-4 days/week at 60% of their individual VO2 max. Before and after this period, resting venous serum osteocalcin and GH concentrations were measured in the same batch. The blood sampling after 8 weeks of the training program were performed after resting for one day. All patients and controls underwent also the following endocrine evaluation: serum cortisol, plasma ACTH.

RESULTS

Our results demonstrate a significant increase of osteocalcin after physical exercise and a positive correlation between osteocalcin and GH. This later might suggest a role of GH in the increased osteocalcin secretion.

CONCLUSIONS

The data of the present study suggest a positive effect of physical exercise on bone metabolism in patients with adrenal incidentaloma.

Use of oxidized and regenerated cellulose in thyroid surgery: a prospective analysis as cause of postoperative hypocalcemia on 485 patients consecutively treated

AIM

The intraoperative hemorrage determines an higher risk of parathyroid glands lesions, and laryngeal nerve injuries. We have examined if the use of oxidized and regenerated cellulose could be a cause of postoperative hypocalcemia because of the compression on the parathyroid glands or for tissue adhesions

METHODS

From June 2009 to December 2010 we have examined 485 patients consecutively treated with total thyroidectomy. The cases examined were divided in two groups on the use of ionized cellulose (group A and B). 24 hours after surgical procedure, all patients were submitted to serum calcium evaluation. The data were analyzed with χ2 test and t-student test; P<0.05 was statistically significant.

RESULTS

We have selected 372 cases out of 485 examined. We have registered after 10 hours from surgical procedure a case of hemorrhage with reintervention in group B (no use of cellulose). The cost of ionized cellulose is € 46; we have used this device in 212 cases on 372 patients undergone to total thyroidectomy, with a cost of € 9 752. The mean value of the serum calcium was statistically different between pre- and postoperative evaluation in all cases (P<0.0001) divided both on gender and on the use of hemostatic devices.

CONCLUSION

In our experience, there isn't a statistically significant difference on incidence of postoperative hypocalcemia, related to use of ionized and regenerated cellulose on mean surgical time in all patients either treated with traditional surgery or with video-assisted procedure.

Somatostatin reduces neuropeptide Y rise induced by physical exercise

The effect of an i. v. infusion of somatostatin (SRIH) 4.1 μg/min×90 min on the basal secretion of NPY and on the NPY response to physical exercise was studied in normal men. Basal NPY secretion was not modified by SRIH infusion, whereas the NPY response to physical exercise was significantly lower in the presence of SRIH. These data suggest the involvement of a somatostatinergic mechanism in the regulation of NPY response to physical exercise.

Can misdiagnosis in pre-operative FNAC of thyroid nodule influence surgical treatment?

BACKGROUND

Pre-operative cytology in thyroid disease remains the most appropriate diagnostic test for defining the nature of a thyroid nodule before surgical excision.

MATERIALS AND METHODS

We selected the most recent 825 surgical thyroid procedures performed in our institution from January 2004 to June 2007; 776 were total thyroidectomies, 23 were lobe-isthmectomies, and 26 were radical neck dissections. We distributed the data based on pre-operative cytology. Each cytological diagnosis was compared to results obtained by definitive histology. Tumors were called incidentalomas if they consisted of a neoplastic focus with a low grade of aggressiveness, as demonstrated by dimension <5 mm, non-aggressive histological subtype.

RESULTS

Of the 541 cases of benign disease, 417 were confirmed as benign. The other 124 cases are listed as follows: 29 follicular adenoma; 76 papillary carcinoma (35 found as incidentalomas), and 19 follicular carcinoma (3 incidentalomas). Cytology suggestive of papillary carcinoma was correct in 95.2% of cases (119/125). The 135 tumors termed "follicular neoplasm" were staged on pathology thus: 56 adenoma (41.4%), 26 carcinoma (19.2%), 13 (9.6%) absence of follicular proliferation, 38 (28.1%) papillary follicular variant, 2 (1.4%) undifferentiated cells. Medullary carcinomas were both confirmed. The "suspicious group" exhibited no malignancy on fine needle aspiration cytology (12 of 21; 57%).

CONCLUSIONS

Cytology has good reliability in malignant lesions. Incidental tumors occurring in benign disease have little impact on clinical and surgical management; "follicular neoplasm" posed two problems - the impossibility of identifying the nature of the tumor, as well as the newer difficulty in distinguishing papillary follicular subtype.

Systemic oxytocin administration modulates NPY response to insulin-induced hypoglycemia in man

The present study was undertaken to establish whether oxytocin (OT) is able to modify the NPY response to insulin-induced hypoglycemia in man. At 8:00 AM of 2 different days at least 1 week apart, 10 normal men were tested with insulin (0.15 IU/kg) and with the administration of OT (infused from time -15-60 min, at a constant rate of 2 mIU/ml) or placebo. Plasma NPY concentrations rose significantly during insulin tolerance test (ITT). Oxytocin treatment significantly reduced the NPY response to hypoglycemia. The finding demonstrates for the first time in humans that the systemic administration of OT exerts an inhibitory effect on the NPY rise caused by insulin-induced hypoglycemia.

Preoperative PTH as a marker of risk for post-thyroidectomy hypocalcemia

AIM

There are no common guidelines to identify the population at risk to develop hypocalcemia preoperatively or early in the postoperative course in thyroidectomized patients, therefore the authors suggest to examine the PTH value preoperatively.

METHODS

We divided 391 patients in two groups according to the preoperative PTH level (normal, ≤ 72 pg/mL vs. increased >73 pg/mL).

RESULTS

In 92/391 cases (23.52%) preoperative PTH was increased (mean PTH level 112.4+/-24.8 pg/mL; normal range 12-72 pg/mL). Out of these, 43 (46.7%) had hypocalcaemia postoperatively. In 18 out of the 43 patients clinical hypocalcemia also developed. The mean follow-up was of 148+/-13 days. Of the 299 patients with normal preoperative PTH, 127 (42.47%) developed postoperative hypocalcemia (mean calcium level 7.4+/-0.33 mg/dL). In 30 patients it was also clinically evident. The difference in terms of incidence of symptomatic hypocalcemia was statistically significant (increased preoperative PTH 19.5% vs. normal preoperative PTH 10.03% , P=0.036).

CONCLUSION

All candidates to thyroidectomy should be investigated for preoperative PTH abnormalities.

Effect of serotonergic system on AVP secretion induced by physical exercise

The present study was undertaken in order to establish the possible involvement of serotonergic receptors in the control of physical exercise-stimulated vasopressin secretion. Twenty-one healthy men (divided in three groups of seven) underwent bicycle-ergometer tests until exhaustion: exercise control test (n=21), exercise plus ondansetron, selective 5-HT3 antagonist (n=7), exercise plus buspirone, selective 5-HT1A receptor agonist (n=7), exercise plus sumatriptan, selective 5-HT1D receptor agonist (n=7). AVP levels, physiological and biochemical variables were measured and compared during tests. Results showed that exercise-induced AVP rise did not change after the administration of buspirone and sumatriptan. In contrast, the administration of ondansetron significantly reduced physical exercise-induced AVP rise. Mean peak levels during physical exercise were 4.9 times higher than basal values in the control test and 2.6 times higher than basal values in the ondansetron plus exercise test. These data demonstrate that 5-HT3 serotonergic receptors at least partially mediate the AVP response to physical exercise. On the other hand, 5-HT1A and 5-HT1D serotonergic receptors do not appear to be involved in the control of AVP secretion during exercise.

Can we use ionized calcium in the evaluation of post-thyroidectomy hypocalcemia?

AIM

The postoperative hypocalcaemia has the higher incidence as complications related to thyroidectomy.

METHODS

From 1 June 2006 to 30 June 2008, we examined 492 patients operated on consecutively in our unit with a total thyroidectomy for thyroid disease. We evaluated the values of ionized calcium in all the cases, matching these with the preoperative and postoperative values of serum calcium. The pre- and postoperative (24 hours after treatment) data for ionized calcium and serum calcium were examined statistically with the Student's t-test; results with a P-value <0.05 were considered to be statistically significant.

RESULTS

Two-hundred-and-twenty-three of the 492 patients (45.2%) treated with total thyroidectomy had preoperative values of ionized calcium lower than 1.13 mmol/L (normal values 1.13-1.32 mmol/L), while the ionized calcium values were lower than 1.10 mmol/L in 154 of the 223 patients. The mean value of ionized calcium in all 223 cases was 1.04+/-0.07 mmol/L. The mean serum calcium value in these patients was 9.13+/-0.291 mg/dL (normal values 8.3-10.5 mg/dL). In the other 259 cases, the values of ionized calcium and serum calcium were 1.21+/-0.03 mmol/L and 9.1+/-0.29 mg/dL, respectively. In 75 cases on 223 with symptomatic hypocalcemia, the mean value of ionized calcium was 0.88+/-0.05 mmol/L, while, in the remaining 148 cases, the mean value was equal to 0.97+/-0.08 mmol/L (P<0.001). We compared this, in both groups, with the values of postoperative serum calcium; in the 75 cases with clinical hypocalcemia, the value of serum calcium was 7.32+/-0.35 mg/dL, while the value was equal to 8.4+/-0.34 mg/dL in the other cases (P<0.001).

CONCLUSIONS

The values of ionized calcium must not be used as marker of hypocalcemia but must be seen as a diagnostic aid linked to others laboratory values, such as serum calcium.

Localization of pathological gland's site in primary hyperparathyroidism: ten years experience with MIBI scintigraphy

BACKGROUND

Primary hyperparathyroidism (PHPT) is characterised by pathological hyperfunctioning of one or more of the parathyroid glands leading to excessive parathyroid hormone (PTH) secretion. The aim of this study was to assess the diagnostic capacity of scintigraphy with MIBI, considering the surgical findings and the level of agreement with the result of cervical ultrasonography.

PATIENTS AND METHODS

In the period January 1996 to January 2006, 84 cases with PHPT were included in the study, in which scintigraphy with MIBI was used in addition to cervical ultrasonography. All were hospitalised as "short stay surgery" patients and then seen as outpatients at follow-up visits (at 7, 14 and 30 days), during which calcium, phosphorus and PTH values were measured.

RESULTS

In 55 cases (65.5%), the site of the pathology was suspected on the basis of the cervical ultrasonography. Scintigraphy with MIBI was positive in 76 cases (90.4%) and negative in the other eight (9.6%). In six of these eight cases the site had been detected by the cervical ultrasonography. In the remaining two cases (2.4%), neither of these examinations gave positive diagnostic findings. In 58 patients we proceeded with the removal of a single adenoma, in 19 cases with the removal of two out of the four glands, and in seven cases with the removal of three out of the four glands, the single formations removed not showing clearly-defined macroscopic characteristics; in two of the seven patients in whom three of the four glands were removed, the preoperative diagnostic examinations had not shown any evidence of gland pathology.

CONCLUSIONS

We regard scintigraphy with MIBI as a preoperative diagnostic examination that has modified the surgical approach to PHPT, inclining surgeons towards a mini-invasive surgical procedures. We consider CT, MRI and SPECT techniques to be indicated only in cases of relapse of PHPT, possibly associated with ectopic localisation of the parathyroid gland not identified in the course of previous surgical procedures.

The association between papillary carcinoma and chronic lymphocytic thyroiditis: does it modify the prognosis of cancer?

AIM

The association between papillary thyroid carcinoma (PTC) and chronic lymphocytic thyroiditis (CLT) has been reported in literature. The aim of this study was to examine this association evaluating the lesser or greater neoplastic aggressiveness.

METHODS

One hundred and eighty-nine patients were examined from June 2004 to June 2007; they were divided into two groups: Group A included all the patients affected by PTC without CLT and Group B all the patients affected by PTC with CLT association. The surgical treatment was in all the patients the total thyroidectomy (TT). For the study age, sex, tumour features (dimensions, angioinvasion, capsular infiltration, multifocality and lymphnode metastases) were taken into consideration. The analysis was carried on with Student t test and chi squared analysis (statistically significant P<0.05).

RESULTS

Group A included 117 patients; Group B 72 patients. No statistical difference in sex (P=0.989), age (P=0.480); tumour dimension (P=0.832). The capsular infiltration was present in 23 cases in Group A and 19 in Group B (P=0.368). The difference in average diameter was found to be 1.161+/-0.5812 and 1.485+/-1.082 cm in Group A and in Group B (P=0.290), respectively. The angioinvasion was found in 9 cases of Group A and in 3 cases in Group B (P=0.510). Multifocality was found in 35 patients in Group A and in 26 in Group B (P=0.469).

CONCLUSION

The CLT may have only a minimum impact in the development of the tumour. In this study the association does not modify the aggressiveness.

Effect of naloxone on somatostatin inhibition of arginine vasopressin response to physical exercise in normal men

To establish whether somatostatin (SRIH) and/or endogenous opioids play a role in the control of arginine-vasopressin (AVP) response to physical exercise, eight healthy men underwent four bicycle-ergometer tests until exhaustion: exercise control test; exercise plus SRIH, naloxone or SRIH plus naloxone. Serum AVP levels, physiological and biochemical variables were measured during tests. Physiological and biochemical variables were similar in all tests. During control test exercise significantly increased serum AVP levels, with a peak value 4.1 times higher than baseline. The AVP response to exercise was similar in the presence of naloxone, whereas it was significantly reduced by SRIH (AVP peak was only 2.8 times higher than baseline). When SRIH and naloxone were given together, the exercise-induced AVP rise was comparable to that observed in the control test. Results indicate a somatostatinergic involvement in the regulation of the AVP response to physical exercise. Furthermore, naloxone-sensitive endogenous opioids appear to play a role in the mechanism underlying SRIH inhibitory action, but not in mediation of the AVP response to physical exercise.

Minimally Invasive Video-Assisted Thyroidectomy: The Learning Curve

<i>Background:</i> MIVAT (minimally invasive video-assisted thyroidectomy) is a recent technique that requires a learning curve. <i>Materials and Methods:</i> From July 2005 to December 2006, we treated 100 from a total of 467 thyroidectomy patients with MIVAT. We divided the patients into 3 groups. The first 2 groups consisted of 25 patients each: group A (cases 1–25) and group B (26–50). We also divided patients into 2 groups based on our surgical experience: group A + B (cases 1–50) and group C (cases 51–100). <i>Results:</i> The operative times for groups A and B were 101.7 and 84.6 min, respectively (p < 0.03); those for groups A + B and C were 91.07 and 63.06 min, respectively (p < 0.004). Complications of hypocalcemia were observed in 6 cases (4 in the first 50 cases and 2 in the second 50), and complications of nerve palsy were observed in 2 cases from group A. <i>Conclusions:</i> After 25 cases, we observed that the MIVAT procedure allows for a lower mean operative time and a reduction of complications.

Pain after minimally invasive videoassisted and after minimally invasive open thyroidectomy--results of a prospective outcome study

BACKGROUND

Substantial modifications in surgical treatment of thyroid disease have changed the postoperative management of thyroidectomized patients. The reduction of postoperative pain permit a short-stay surgery.

MATERIALS AND METHODS

We have analyzed the patients treated in our Unit from July 2006 to December 2006, with minimally invasive cervicotomy and mini-invasive video-assisted thyroidectomy. We have registered the postoperative pain applying an evaluation protocol numeric scale. The results were analyzed by t test.

RESULTS

One hundred thirteen patients were divided in two groups: group A, minimally invasive cervicotomy (15 male and 46 female patients); group B, mini-invasive video-assisted thyroidectomy (9 male and 43 female patients). Upon returning to the ward, the pain scale group A vs B was 2.77 +/- 1.16 vs 2.5 +/- 0.762 (p = 0.22) .At 24 h after surgery, the pain scale in group A was 1.82 +/- 1.258 vs 1.031 +/- 0.8608 (p < 0.005).

CONCLUSIONS

Both methods are safe, but mini-invasive video-assisted thyroidectomy gives not only a better cosmetic result but a reduction of postoperative pain especially at 24 h.

[Compared progression of visual-evoked potentials in preterm and term newborns]

PURPOSE

To compare the development of the visual pathway in healthy preterm and full-term newborns using flash and patterned (both transient and steady-state) visual-evoked potentials (fVEP, pVEP-t, pVEP-ss).

PATIENTS AND METHODS

Twenty-nine preterm newborns (28-35 weeks gestational age) were evaluated at four different times: at 3 months postnatal and corrected age, at 8 months postnatal and corrected age. They were matched with 92 term newborns tested at 3 and 8 months of life.

RESULTS

The maximal perceived spatial frequencies in the groups were: 2 C/d at 3 months postnatal age, >2 C/d at 3 months corrected age and at 3 months at term, between 3 and 5C/d, >=5C/d at 8 months corrected age and at 8 months of life, respectively. The latencies of the P1 and P100 waves for the flash and the transient stimulation were, respectively, 192 ms and 207.9 ms at 3 months postnatal age, 144 ms and 137.7 ms at 3 months corrected age, 126.3 ms and 124.1 ms at 8 months postnatal age, 112.7 ms and 112.5 ms at 8 months corrected age, 137.3 and 110.1 ms at 3 months of life; and 122.3 and 100.5 ms at 8 months of life.

DISCUSSION

In the preterm infants of 3 gestational months, the latencies of the fVEP are comparable to those of the 3-month-old full-term infants, although the pVEP-t latencies are still delayed at 8 months. In the fVEP; however, we noted a shorter latency in the preterm infants at 8 months corrected age compared to those of the full-term infants. This tendency inversion was also evidenced at the steady-state stimulation.

CONCLUSIONS

As evidenced by our results, at 8 months of corrected age the preterm infants recovered the fVEP and pVEP-ss, but not the pVEP-t. Different results obtained with different visual-evoked stimulations suggest that similar neural pools are developed in not completely equal amounts of time.

The transition from relapsing-remitting MS to irreversible disability: clinical evaluation

The development of a progressive course is by far the most deleterious event in the case of a multiple sclerosis (MS) patient. It occurs in about 90% of relapsing remitting patients by 20-25 years from onset. The clinical transition to secondary progressive MS is phenotypically distinctive and both patients and physicians acknowledge that a fundamental shift in the degree of responsiveness to anti-inflammatory therapies has occurred. This review discusses the clinical studies that provided important findings relating to our understanding on different mechanisms that may contribute to irreversible disability in MS.

Effect of dexamethasone on TSH secretion induced by TRH in human obesity

BACKGROUND

The presence of an abnormally high thyroid-stimulating hormone (TSH) response to thyrotropin-releasing hormone (TRH) makes it difficult to distinguish some euthyroid obese subjects from subelinically hypothyroid obese patients. Here, we examine whether such distinction may be achieved after treatment with glucocorticoids, which inhibit TSH secretion at the hypothalamic-pituitary level.

METHODS

TRH tests (200 microg as an intravenous bolus injection) were performed in 30 age- and weight-matched, obese, but otherwise healthy, men. All subjects were tested again with TRH after treatment with dexamethasone (dex) (2 mg/d in four divided doses orally for 3 days).

RESULTS

In all subjects, total thyroxine and triiodothyronine concentrations were in the normal range. According to basal and TRH-stimulated serum thyrotropin (TSH) levels, subjects were divided into the following three groups: group I (n=10), euthyroid subjects; group II (n=10), euthyroid subjects with normal basal but abnormally elevated TSH responses to TRH; group III (n=10), subjects with elevated basal and TRH-induced TSH levels (subclinical hypothyroidism). Basal TSH levels were 1.8+/-0.4 mU/L in group I, 1.7+/-0.3 in group II, and 6.0+/-0.7 in group III. In both groups II and III, TRH-induced TSH increments were above the normal range (maximal increment> 15 mU/L) and were significantly higher than in group I. After the second treatment with TRH, pretreatment with dex significantly decreased both basal TSH levels and peak TSH responses to TRH in all groups. However, a striking percentage decrease (>50%) in TRH-induced peak TSH responses was observed in euthyroid obese subjects of groups I and II, whereas hypothyroid subjects of group III showed only a slight decrement (<25%).

CONCLUSIONS

The sensitivity of the TSH secretory system to glucocorticoid inhibitory action is preserved in obese subjects with abnormally elevated TSH response to TRH, but not in subclinically hypothyroid obese patients. The TRH plus dex test might be useful in future studies to understand the mechanisms underlying alterations in TSH secretion in obesity.

Effect of systemic oxytocin administration on dexamethasone-induced leptin secretion in normal and obese men

To establish whether the regulatory mechanism of leptin secretion is sensitive to oxytocin (OT), seven healthy nonobese men were tested with dexamethasone (dex; 4 mg, iv, at 0730 h) in feeding (2000 Cal given at 3 meals over 7 h) conditions either in the absence (iv normal saline infusion) or in the presence of a constant iv infusion of OT (1, 2, or 4 mIU/min from 0730 h for 10 h). In six additional subjects under similar experimental conditions, normal saline or OT (1, 2, or 4 mIU/min from 0730 h for 10 h) were infused iv without the previous treatment with dexamethasone. Serum leptin concentrations were measured in samples taken at 60-min intervals during infusion. Leptin levels remained constant during the infusion of normal saline or OT (1, 2, or 4 mIU/min) alone. In contrast, serum leptin concentrations rose significantly from the baseline after dex administration. The leptin response to dex was not modified by the concomitant infusion of 1 mIU/min OT, whereas it was completely abolished by the administration of 2 or 4 mIU/min OT. These findings led us to evaluate the secretory pattern of leptin in 12 obese patients in similar experimental conditions. In all patients basal leptin levels were significantly higher than those in normal weight subjects. In 6 obese subjects, the infusion of OT alone (1, 2, or 4 mIU/min) was unable to change serum leptin levels. In the remaining 6 obese subjects, dex administration significantly increased serum leptin levels; however, the leptin response to dex was not modified by the concomitant infusion of 1, 2, or 4 mIU/min OT. These data show inhibition by elevated circulating OT levels of glucocorticoid-induced, but not basal, leptin secretion in normal weight subjects, suggesting a possible role for OT in the regulatory control of leptin. Furthermore, the results obtained in obese subjects indicate that this regulation is disrupted in obesity.

Effect of aging on the arginine-vasopressin response to physostigmine and angiotensin II in normal men

The effect of age on the stimulatory control exerted by cholinergic- and angiotensin II (ANG II)-mediated neurotransmission on arginine vasopressin (AVP) secretion was evaluated by measuring and comparing the AVP responses to the administration of either the cholinesterase inhibitor physostigmine (13.5 micrograms/kg in 50 mL normal saline infused in 10 minutes) or ANG II (increasing doses of 4, 8, and 16 micrograms/kg/min, each dose for 20 min) in 8 younger (23-37 years), 8 middle age (42-60 years), and 8 older (63-79 years) healthy male subjects. Both drugs induced significant increments in plasma AVP levels in the youngest group, with mean peak levels 4.8 times higher than baseline at 20 minutes after the beginning of physostigmine infusion and 1.5 times higher than baseline at 60 minutes after the beginning of ANG II infusion. Similar responses were observed in the middle age group. Basal AVP levels in older subjects were similar to those observed in the other groups. However, the AVP increases induced by physostigmine (mean peak was 9 times higher than baseline) and ANG II (mean peak was 2.2 times higher than baseline) were significantly higher in the oldest group than in the other groups. These data suggest age-related enhancement of the stimulatory regulation exerted by cholinergic- and ANG II-mediated neurotransmission on AVP secretion.

Dopaminergic and cholinergic involvement in the inhibitory effect of dexamethasone on the TSH response to TRH

BACKGROUND

Glucocorticoid administration is associated with reduced basal thyroid-stimulating hormone (TSH) levels and a blunted TSH response to thyrotropin-releasing hormone (TRH), despite thyroid hormone levels within the normal range. In light of the inhibitory effect of somatostatin and dopamine on TSH secretion, we examined whether this condition is caused by glucocorticoids through an increased hypothalamic somatostatinergic and/or dopaminergic inhibitory control of TSH. We measured the TSH response to TRH and serum-free T4 and T3 levels. The study group comprised 18 normal men (age 24-35) within 10% of the ideal body weight, randomly divided into 3 groups of six.

METHODS

We used the antidopaminergic agent metoclopramide (MCP) and the acetylcholinesterase inhibitor pyridostigmine, which enhances acetylcholine and thus inhibits hypothalamic somatostatin release. Subjects from group 1 were tested with TRH (20 micrograms in an intravenous bolus) after placebo, dexamethasone (dex) (2 mg/day in 4 divided doses for 3 days before the experimental day), or dex plus pyridostigmine (120 mg p.o.). Subjects from group 2 were tested with TRH after placebo, dex, or dex plus MCP (2.5 mg in an i.v. bolus injection). Subjects from group 3 were tested with TRH after placebo, dex, or dex plus pyridostigmine plus MCP.

RESULTS

In all subjects from groups 1, 2, and 3, TRH-induced TSH rise was significantly lower after dex than after placebo treatment. Neither pyridostigmine nor MCP, given alone, changed the TSH response to TRH after dex treatment. In contrast, the concomitant administration of MCP and pyridostigmine significantly enhanced the TRH-induced TSH rise in dex-treated subjects and made the TSH response to TRH similar to that observed in the TRH plus placebo test.

CONCLUSIONS

These data indicate that enhanced-hypothalamic somatostatinergic and dopaminergic inhibitory activities are involved in the mechanism underlying the reduced TSH response to TRH induced by glucocorticoid treatment.