Shallow-Water Hydrothermal Vents as Natural Accelerators of Bacterial Antibiotic Resistance in Marine Coastal Areas

Environmental contamination by heavy metals (HMs) poses several indirect risks to human health, including the co-spreading of genetic traits conferring resistance to both HMs and antibiotics among micro-organisms. Microbial antibiotic resistance (AR) acquisition is enhanced at sites anthropogenically polluted by HMs, as well as in remote systems naturally enriched in HMs, such as hydrothermal vents in the deep sea. However, to date, the possible role of hydrothermal vents at shallower water depths as hot spots of microbial AR gain and spreading has not been tested, despite the higher potential risks associated with the closer vicinity of such ecosystems to coasts and human activities. In this work, we collected waters and sediments at the Panarea shallow-water hydrothermal vents, testing the presence of culturable marine bacteria and their sensitivity to antibiotics and HMs. All of the bacterial isolates showed resistance to at least one antibiotic and one HM and, most notably, 80% of them displayed multi-AR on average to 12 (min 8, max 15) different antibiotics, as well as multi-HM tolerance. We show that our isolates displayed high similarity (≥99%) to common marine bacteria, affiliating with Actinobacteria, Gammaproteobacteria, Alphaproteobacteria and Firmicutes, and all displayed wide growth ranges for temperature and salinity during in vitro physiological tests. Notably, the analysis of the genomes available in public databases for their closest relatives highlighted the lack of genes for AR, posing new questions on the origin of multi-AR acquisition in this peculiar HM-rich environment. Overall, our results point out that shallow-water hydrothermal vents may contribute to enhance AR acquisition and spreading among common marine bacteria in coastal areas, highlighting this as a focus for future research.

Response of vanadium bioaccumulation in tissues of Mugil cephalus (Linnaeus 1758)

Vanadium accumulation levels in different tissues (muscle and organs) of the striped mullet Mugil cephalus (Linnaeus, 1758) and possible relationships with blood parameters were evaluated in a Natural Protected Area (Lake Faro, Sicily, Italy), during the winter of 2017. Hematological parameters (red blood cell, RBC; white blood cell, WBC; hemoglobin concentration, Hb; hematocrit, Hct; mean corpuscular volume, MCV; mean corpuscular hemoglobin, MCH; mean corpuscular hemoglobin concentration, MCHC; thrombocytes, TC), biometric indices (weight, total and fork length), and vanadium levels in muscles and organs (gills, liver, stomach and intestine) were determined. Statistical analyses showed significant differences in concentrations of vanadium of the analyzed tissue of M. cephalus and a positive relationship between vanadium concentration in the liver and some hematological parameters (RBC, Hb and Hct) and biometric indices. Our results underline the importance of fish blood parameters as sensitive indicators of toxic impact of environmental factors such as metals. This study, focusing on an ongoing topic, represents a valuable contribution to research concerning the monitoring and prevention of vanadium pollution in aquatic organisms and environments.

Plastics occurrence in the gastrointestinal tract of Zeus faber and Lepidopus caudatus from the Tyrrhenian Sea

The present study investigates the occurrence of plastic pollution in two commercially important marine teleosts (Zeus faber and Lepidopus caudatus) from the northern coasts of Sicily (Tyrrhenian Sea). Plastics occurrence in the gastrointestinal tract was higher in Lepidopus caudatus (78.1%) than Zeus faber (51.4%). Debris characterization, carried out by micro-Raman spectroscopy, allowed identified the main types of found polymers as: polypropylene (PP), polyamide (PA), nylon and, to a lesser extent, polyethylene (PE). Of the two fish species studied, the silver scabbardfish appeared to be the more vulnerable to plastic ingestion. Our study represents a starting point that may pave the way for future investigation of the fate, accumulation and transfer of plastic debris to upper trophic levels, to verify their potential toxicity and to better understand strategies to mitigate this phenomenon.

New Insights into the Culture Method and Antibacterial Potential of Gracilaria gracilis

Enormous marine biodiversity offers an endless reservoir of chemicals for many applications. In this scenario, the extraction of seaweeds represents an interesting source of compounds displaying antimicrobial activity. In particular, among the different red algae, Gracilaria gracilis plays an important role due to the presence of important bioactives in its composition. In spite of these features, an efficient culture system is still absent. In the present study, a novel algal culture method was developed and compared to another more common cultural practice, widely reported in literature. A higher efficiency of the new method, both for daily growth rate and biomass, was assessed. Furthermore, the growth inhibitory activity of five extracts, obtained using ethanol, methanol, acetone, chloroform or diethyl ether as a solvent, from the cultured G. gracilis was tested against Gram-positive and Gram-negative pathogens. Algal extracts exhibited a considerable inhibitory activity against B. subtilis strains, while a slight inhibition was observed against V. fischeri. The different extracts showed significant differences in bacterial growth inhibition, with the highest activity that was recorded for the ethanol extract, followed by that of methanol. Based on the chemical characterization, these findings could be related to the antimicrobial activity played by the combination of total carbohydrates and polyphenols, which were determined at high levels in ethanol and methanol extracts, as well as by the highest number and levels of single polyphenols. Conversely, the lower growth inhibitory activities found in chloroform and diethyl ether extracts could be related to the isolation of minor lipid classes (e.g., neutral and medium polar lipids) composed by fatty acids, such as stearic, oleic and arachidonic acids, typically characterized by antimicrobial activity. In consideration of the results obtained, the present study has a double implication, involving both the field of cultural practices and the exploitation of natural sources for the isolation of antimicrobial agents useful both in pharmaceutical and food applications.

Effect of sodium dodecyl sulfate (SDS) on stress response in the Mediterranean mussel (Mytilus Galloprovincialis): regulatory volume decrease (Rvd) and modulation of biochemical markers related to oxidative stress

In this study the effects of an anionic surfactant, sodium dodecyl sulfate (SDS), are assessed on the Mediterranean mussel (Mytilus galloprovincialis), exposed for 18 days at a concentration ranging from 0.1 mg/l to 1 mg/l. The effects are monitored using biomarkers related to stress response, such as regulatory volume decrease (RVD), and to oxidative stress, such as reactive oxygen species (ROS), endogenous antioxidant systems and Hsp70 levels. The results demonstrate that cells from the digestive gland of M. galloprovincialis, exposed to SDS were not able to perform the RVD owing to osmotic stress. Further, SDS causes oxidative stress in treated organisms, as demonstrated by the increased ROS production, in comparison to the controls (p<0.05). Consequently, two enzymes involved in ROS scavenging, superoxide dismutase (SOD) and catalase (CAT) have higher activities and the proportion of oxidized glutathione (GSSG) is higher in hepatopancreas and mantle of treated animals, compared to untreated animals (p<0.05). Furthermore Hsp70 demonstrates an up-regulation in all the analyzed tissues of exposed animals, attesting the stress status induced by the surfactant with respect to the unexposed animals. The results highlight that SDS, under the tested concentrations, exerts a toxic effect in mussels in which the disruption of the osmotic balance follows the induction of oxidative stress.

Impacts of marine aquaculture at large spatial scales: evidences from N and P catchment loading and phytoplankton biomass

While several studies point at off-shore aquaculture as a possible source of impacts on the local marine environment, very few have analysed its effects at large scales such as at the bay, gulf or basin levels. Similar analyses are hampered by the multiple sources of disturbance that may concomitantly affect a given area. The present paper addresses these issues taking the Gulf of Castellammare (Southern Tyrrhenian Sea) as an example. Nitrogen (N) and phosphorous (P) loads were calculated for the period 1970-2007, and compared to chlorophyll-a concentration as measured inside and outside the Gulf over the same period. Results indicate that N and P catchment loading has constantly decreased because of improved environmental management. Nevertheless, nutrient concentration in the Gulf has steadily increased since the establishment of aquaculture facilities in 1999. Chlorophyll-a concentration followed this trend, showing a marked increase from 2001 onwards. In the same period, chlorophyll-a concentrations measured inside and outside the Gulf have significantly diverged. As all the other possible causes can be ruled out, aquaculture remains the sole explanation for the observed situation. This paper demonstrates for the first time ever that off-shore aquaculture may affect the marine ecosystem well beyond the local scale and provides an additional element of concern to be kept into consideration when allocating oceans' space for new fish-farming activities.

Contrast-enhanced ultrasonography (CEUS) in retroperitoneal liposarcomas

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Background: CEUS with second-generation contrast agents has been proposed to monitor tumor response to imatinib in patients with metastatic GIST. There are no data in patients with other sarcomas. Our aim was to assess the value of CEUS as a marker of tumor response in retroperitoneal liposarcoma, in addition to its ability to render the baseline malignancy grade of the disease. Methods: CEUS was performed after a SonoVue injection (Bracco, Milano, Italia). SonoVue is a suspension of microbubbles of exafluoride sulphure gas (average diameter 3 μm) with a phospholipidic shell. A low mechanical index (MI<0.09) was used in order to minimize microbubbles rupture. Ultrasound device systems (Philips ATL HDI 5000, Bothel, Washington) with a broandband probe (2–5 Mhz) and specific contrast agent algorithms (Pulse Inversion Harmonic Imaging) were used. The use of this algorithm allowed a real time imaging of all vascular phases (arterial, portal and late). All patients underwent CT scan, PET tomography and routine blood examinations. Ten patients with retroperitoneal liposarcomas were enrolled in this study (5 high grade, 3 intermediate grade, 2 low grade). Results: Five males and five females with metastatic or relapsed disease were enrolled. Median age was 57 years (range 40–70). All underwent chemotherapy with Ifosfamide and Doxorubicin. In all patients there was a clear correlation between contrast enhancement and grading: in low-grade patients there was no contrast enhancement, while the highest level of enhancement was seen in undifferentiated sarcomas. With regard to tumor response to chemotherapy, only 4 patients were evaluable. One patient had a PR and 3 patients had PD. In the 3 patients with PD CEUS showed contrast enhancement, PET was uptaking, but CT scan did not detect any change. In the patient with a PR, strong decrease of tumor perfusion on CEUS and uptaking on PET was seen, again with no change on CT scan. Conclusions: These preliminary observations suggest that CEUS may be more useful than CT scan on assessing tumor response in retroperitoneal sarcomas, and may predict the baseline malignancy grade. Data on a larger number of patients will be presented.

No significant financial relationships to disclose.

Gastrointestinal stromal tumors (GISTs): focus on histopathological diagnosis and biomolecular features

Gastrointestinal stromal tumors (GISTs) are mesenchymal tumors of the gastrointestinal tract that are believed to originate from a neoplastic transformation of the intestinal pacemaker cells (interstitial cells of Cajal) normally found in the bowel wall or their precursors. Although the microscopic features have been known for a long time, the defining characteristic of GIST is the presence of the cell-surface antigen CD117 (KIT), which is demonstrated by immunohistochemistry. KIT, which is a growth factor transmembrane receptor, is the product of the proto-oncogene c-kit (chromosome 4). Surgical removal remains the only curative treatment for patients with GISTs. Tumor size, mitotic index, anatomic location, tumor rupture and disease-free interval are the classic characteristics used to predict the clinical course of patients who undergo complete gross resection. Most GISTs express constitutively activated mutant isoforms of KIT or kinase platelet-derived growth factor receptor alpha (PDGFRA) that are potential therapeutic targets for imatinib mesylate. Imatinib mesylate is a rationally designed, molecularly specific oral anticancer agent that selectively inhibits several protein tyrosine kinases central to the pathogenesis of human cancer and which has demonstrated remarkable clinical efficacy in patients with chronic myeloid leukemia and malignant GISTs. More recently Sunitinib, a new KIT/PDGFRA kinase inhibitor, has been tested in patients with GIST resistant to imatinib, with promising results.

Prolonged mivacurium-induced neuromuscular block. Case report

A 38-year-old white male patient was admitted to the hospital for elective surgery. General anesthesia was performed with propofol, alfentanil, nitrous oxide and mivacurium as neuromuscular blocker. Seven months before he had the same surgery without anesthetic problems (he received: propofol, vecuronium bromide, fentanil, nitrous oxide). Neuromuscular monitoring was carried out because the patient was included in a study assessing the clinical effect of mivacurium in microlaryngoscopy surgery. After mivacurium administration the first signs of recovery from neuromuscular block were observed after 255 min. The tracheal tube was withdrawn after 410 min from mivacurium administration, at this time the T1 was 80% of the control values and 7 min later the T1 reached 98%.

Laparoscopic cholecystectomy in a patient with mitochondrial myopathy

The authors report a 27-year-old woman with mitochondrial myopathy and respiratory failure requiring nasal-CPAP administration who successfully underwent laparoscopic cholecystectomy for chronic cholecystitis. The hypothesis that minimally invasive surgery results in less operative stress is truly substantiated by the experience with laparoscopy in such patients with high risk of perioperative and postoperative complications.

Transabdominal preperitoneal laparoscopic inguinal herniorrhaphy (TPLIH) under regional anaesthesia

BACKGROUND

In an attempt to investigate whether laparoscopy really is a major advance in the treatment of inguinal hernia, the authors performed laparoscopic transabdominal preperitoneal inguinal herniorrhaphy under regional anaesthesia in 15 consecutive patients, 7 of whom with severe medical conditions contraindicating general anaesthesia.

METHODS

In the first 5 patients (Group 1) an epidural anaesthesia was performed, whereas in the following 10 patients (Group 2), fentanyl was added to the epidural anaesthesia, and bupivacaine was administered into the subarachnoid space.

RESULTS

Results from Group 1 were poorer than those obtained in Group 2. All patients complained of shoulder pain and discomfort which required the intraoperative administration of analgesics in 7 patients and conversion to open repair in one patient.

CONCLUSIONS

Although laparoscopy is a feasible and effective procedure in repairing inguinal hernias, it is not indicated in high-risk patients who can be safely, effectively, and less expensively treated with open tension-free repair techniques under local anaesthesia.

[New studies on population of the North American colonies from the seventeenth to the nineteenth century and some reflections on migration in the modern age]

"In recent years, many authors worked on modern era population movements between 1492 and 1870. American scholars stressed that the settlement of the North American colonies, during [the] 17th and 18th centuries, should be considered a form of migration and should be analysed with the same tools used for the study of the great migration of the 19th century. Instead European scholars tried to pinpoint when 'old regime' migrations developed into the 'great migration'.... This review aims at presenting the most important European and American publications on this topic and points to the subjects to be developed." (SUMMARY IN ENG AND FRE)

[Effects of betamethasone on neuromuscular blockade induced by vecuronium in continuous infusion]

The aim of the study was to determine a possible interaction between a corticosteroid (betamethasone) and vecuronium, a nondepolarizing muscle relaxant. The authors studied 20 patients, ASA I-II, aged 20-54, both sexes, scheduled for abdominal surgery. Mechanomyographic and clinical evaluation by single twitch and TOF stimulation of the ulnar nerve at the wrist and measurement of the concomitant abductor pollicis muscle was applied. The onset time of vecuronium after a single bolus dose of 0.08 mg/kg, duration of action to 10% single twitch recovery, duration of continuous infusion of 0.4-0.5 micrograms/kg/min of vecuronium started at 10% single twitch recovery, and the effects of 0.1 mg/kg betamethasone administration 10 min after continuous infusion were evaluated. The recovery rate of vecuronium after stopping infusion at 10% recovery was also evaluated. Corticosteroids may interact with non-depolarizing muscle relaxants both in prejunctional and postjunctional acetylcholine receptors by several mechanisms of action.

[Short-term and long-term surgical prophylaxis with pefloxacin]

In the present study the efficacy and safety of pefloxacin (400 mg/5 ml vial) intravenously administrated for surgical prophylaxis was assessed. Nine hundred and fifty-two patients were treated (599 M, 343 F), with a mean age of 57.9 years +/- 18.6 SD, and in all cases surgical prophylaxis was carried out according to the following scheme: short-term with 2 vials (800 mg) 1 h before the operation, repeated at 12 and 24 hours after the operation; long-term 2 vials (800 mg) 1 h before the operation repeated at 12 and 24 hours after the operation and followed by 1 vial every 12 h for other 2 days. The choice between the two schemes was conditioned by the type of operation and by the basic conditions of the patient. Pefloxacin was seen to be effective in preventing the onset of post-surgical infections (97%), also maintaining the clinical parameters considered within normal limits. Safety was also highly satisfactory, since only 22 (2.3%) cases of side effects occurred, particularly involving the gastro-intestinal system. Thus, in conclusion, the validity of pefloxacin in surgical prophylaxis, with special emphasis on its efficacy in elderly and compromised patients is asserted.

[Myorelaxants and intracranial pressure (ICP) in neurosurgery. Preliminary clinical results of pipecurium bromide (Arduan) on ICP and on cerebral perfusion pressure (CPP)]

Pipecurium bromide, a new non-depolarizing myorelaxant, was administered intravenously, at a dose of 0.06 mg/kg, to 10 patients suffering from expansive endocranial lesions, who had been anesthetised to undergo neurosurgery. The following parameters were recorded simultaneously, before and after drug administration: intracranial pressure, mean arterial blood pressure, central venous pressure, heart rate and end tidal CO2. No statistically significant changes in the above parameters were observed following the administration of the myorelaxant; these observations, which were considered together with the long duration of action, confirm that pipecurium bromide is a valuable tool in anesthesia for neurosurgery.

Clinical evaluation of different doses of pipecuronium bromide during nitrous-oxide-fentanyl anaesthesia in adult surgical patients

The neuromuscular and cardiovascular effects of three different doses of pipecuronium were studied in 60 adult patients. Neuromuscular blockade was measured using electromyographic activity of the adductor pollicis muscle after supramaximal stimulation of the ulnar nerve at 0.1 Hz and 2 Hz. Three subgroups (A, B, C) of 20 patients received pipecuronium doses of 60, 80 and 100 micrograms kg-1, respectively, as an intubating dose and, when necessary, maintenance doses were administered at 25% single twitch recovery in a dose of one-quarter of the initial one. The onset time was 5.4 +/- 2.0 min for 60 micrograms kg-1 and similar for 80 and 100 micrograms kg-1 (3.9 +/- 1.1 and 3.6 +/- 1.1 min). The duration of action was 45 +/- 10 min for 60 micrograms kg-1, 74 +/- 25 and 94 +/- 21 for 80 and 100 micrograms kg-1, respectively. The recovery indices were measured in all patients after neostigmine administration (Groups B and C) and after neostigmine and edrophonium (Subgroup A, 10 patients each). TOF ratio was significant only 2 min after edrophonium administration in Group A patients. Variations of heart rate and blood pressure were not significant.

The Effects of Pipecuronium Bromide on Intracranial Pressure and Cerebral Perfusion Pressure

Twenty patients with expansive pathologic intracranial lesions, who were anesthetized with thiopental, nitrous oxide in oxygen, and fentanyl and mechanically ventilated to ensure normocarbia, received pipecuronium bromide 70 microg/kg i.v. Intracranial pressure (ICP), heart rate, arterial pressure, central venous pressure (CVP), EKG, and end-tidal CO2 were simultaneously recorded for 5 min before and for 15 min after administration of the muscle relaxant. No statistically significant changes in ICP and cerebral perfusion pressure were observed after administration of pipecuronium bromide. Cardiovascular stability was maintained during the study period except for a small, although significant, decrease of the CVP from 5.7 +/- 2.5 (SEM) to 5.0 +/- 2.5 mm Hg. These results, together with the long-lasting muscular effect of pipecuronium bromide, suggest that this new neuromuscular blocking agent may be used for muscle relaxation during neurosurgical operations in patients who have normal intracranial pressure at the time of administration of the drug.

[Diazepam versus midazolam for "wakeful sedation" in oral surgery]

I.v. midazolam was compared with diazepam in 112 dental outpatients in order to obtain a control of sedation. Midazolam has shown better results in all the parameters evaluated (memory scale, pharmacokinetics and pharmacodynamics values) and in controlling sedation. The Authors consider midazolam as a preferred drug in dental outpatients and hope to get it available also in Italy.

Bowel frequency in healthy children

Bowel frequency was recorded, on a diary sheet basis, in 662 children from six Italian cities. There is a wide interindividual variability, showing a sharp decrease with age; we report the distribution of the percentiles in the different age groups. Among infants, the breast-fed ones pass significantly more stools than the formula-fed.

Neostigmine and edrophonium as antagonists of atracurium and pancuronium

Edrophonium 0.5 mg/kg or neostigmine 0.04 mg/kg were administered to two groups of 30 patients each for antagonism of atracurium- or pancuronium-induced neuromuscular block at 25% single twitch recovery. Neuromuscular block was studied using both single twitch and train-of-four (TOF) nerve stimulation. The times to 100% single twitch recovery were significantly more rapid for patients receiving edrophonium (P less than 0.01) in both groups (atracurium and pancuronium); the TOF ratios were similar for atracurium, but for pancuronium they were greater after neostigmine than after edrophonium, and only at 25 min were these ratios similar. It is concluded that edrophonium in a dose of 0.5 mg/kg antagonizes neuromuscular blockade induced by atracurium, as does neostigmine in a dose of 0.04 mg/kg, but the former does not consistently antagonize neuromuscular blockade induced by pancuronium even at 25% of single twitch recovery.

Effects of vecuronium bromide on intracranial pressure and cerebral perfusion pressure. A preliminary report

The effects of vecuronium 0.1 mg kg-1 on intracranial pressure, heart rate and arterial pressure were evaluated in 20 anaesthetized patients with intracranial tumours undergoing neurosurgery. Apart from a slight decrease in intracranial pressure (-4.9%; ns) which was most probably the result of a concomitant decrease (-14.9%) in central venous pressure, vecuronium 0.1 mg kg-1 was without effect on either cerebral or systemic haemodynamics.

The effects of atracurium besylate (Tracrium) on intracranial pressure and cerebral perfusion pressure

Twenty-five patients with expansive pathologic brain lesions, who were anesthetized with thiopental, nitrous oxide in oxygen, and fentanyl, and who were mechanically ventilated to ensure normocarbia, received atracurium besylate 0.6 mg/kg, intravenously. Intracranial pressure, mean arterial pressure, central venous pressure, heart rate, and end-tidal CO2 were simultaneously recorded for 5 min before and for 10 min after administration of the muscle relaxant. No statistically significant changes were observed after administration of atracurium besylate. These results suggest that atracurium besylate may be used for muscle relaxation during neurosurgical operations, despite its potential for histamine release and excitement of the central nervous system.