Bloodstream infections and antibiotic resistance patterns: a six-year surveillance study from southern Italy.

Bloodstream infections (BSI) are associated with high morbidity and mortality. This study aimed to describe the epidemiology of BSI and antimicrobial resistance patterns amongst its common bacterial causes. We conducted a retrospective record review of blood culture results of patients hospitalized with BSI at University Hospital 'L. Vanvitelli' from 2016 to 2021. For each patient records were obtained from the database using microbiological information. Gram-positive bacteria were the most predominant pathogens followed by Gram-negative bacteria. Among all isolates, bacterial pathogens most frequently identified included coagulase-negative Staphylococci (CoNS), Klebsiella pneumoniae, Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and enterococci. We noted a general decrease in antimicrobial resistance amongst BSI pathogens in the latter years of the study. High levels of macrolide and aminoglycoside resistance amongst CoNS were reported. Carbapenem resistance amongst E. coli was barely reported, while resistance rates amongst K. pneumoniae declined considerably between 2018 and 2021. The prevalence of methicillin-resistant S. aureus decreased during the study period while that of methicillin-resistant CoNS remained relatively high throughout. The prevalence of extended spectrum ß-lactamase - producing E. coli increased considerably between 2016 and 2018 but showed a slight decrease thereafter. Conversely, there was a general decline in the resistant rates of extended spectrum ß-lactamase - producing K. pneumoniae between 2016 and 2018 with a similar trend being noted for carbapenem resistance in K. pneumoniae. Continuously monitoring the changes in the trends in BSI microbiological profiles, including pathogen profiles and the associated antibiotic resistance patterns, can help diagnostic approaches, treatment strategies and prevention programs.

Methicillin-resistant Staphylococcus aureus: epidemiology and antimicrobial susceptibility experiences from the University Hospital 'Luigi Vanvitelli' of Naples.

Methicillin-resistant Staphylococcus aureus (MRSA) is one of the important pathogens worldwide showing resistance to several widely used antibiotics. This has made the treatment of MRSA infections harder, especially due to their prevalence in the hospital setting. We evaluated the antibiotic susceptibility patterns of healthcare-associated MRSA infections with a focus on Vancomycin Intermediate S. Aureus (VISA) and macrolide-licosamide-streptogramin B (MLSB) phenotypes. A total of 417 Staphylococcus aureus (S. aureus) cases were isolated between January 2017 and December 2018, through several clinical specimens collected from the University Hospital 'Luigi Vanvitelli' of Naples. We identified bacterial strains using Matrix-Assisted Laser Desorption/Ionization-Time of Flight (MALDI-TOF) and antimicrobial susceptibility using Phoenix BD (Becton Dickinson, NJ, USA). Out of the total 417 S. aureus cases, 140 were MRSA (33.6%) and of these, 50% were soft tissue infections. All MRSA and Methicillin sensible S.aureus MSSA isolates were susceptible to linezolid and daptomycin. Two MRSA cases exhibited intermediate resistance to vancomycin and were of constitutive MLSB phenotype. Among the MRSA strains, 11.4% were constitutive and 43.6% were inducible MLSB phenotypes and 8.6% were macrolide-streptogramin B phenotype. This study characterized the epidemiological status, antibiotic resistance patterns, and current prevalent phenotypes of healthcare-associated MRSA. This knowledge can aid clinicians in improving the antimicrobial stewardship program by adapting appropriate guidelines for the proper use of MRSA antibacterial agents.

Probing electron-phonon excitations in molecular junctions by quantum interference.

Electron-phonon coupling is a fundamental inelastic interaction in condensed matter and in molecules. Here we probe phonon excitations using quantum interference in electron transport occurring in short chains of anthraquinone based molecular junctions. By studying the dependence of molecular junction's conductance as a function of bias voltage and temperature, we show that inelastic scattering of electrons by phonons can be detected as features in conductance resulting from quenching of quantum interference. Our results are in agreement with density functional theory calculations and are well described by a generic two-site model in the framework of non-equilibrium Green's functions formalism. The importance of the observed inelastic contribution to the current opens up new ways for exploring coherent electron transport through molecular devices.

Measurement of the current-phase relation of superconducting atomic contacts.

We have probed the current-phase relation of an atomic contact placed with a tunnel junction in a small superconducting loop. The measurements are in quantitative agreement with the predictions of a resistively shunted SQUID model in which the Josephson coupling of the contact is calculated using the independently determined transmissions of its conduction channels.

Lateral popliteal sciatic nerve block: a single injection targeting the tibial branch of the sciatic nerve is as effective as a double-injection technique.

BACKGROUND: Evidence indicating that single- and double-injection techniques for inducing a sciatic nerve block via a posterior subgluteal approach yield a similar success rate prompted us to investigate whether the two anesthetic techniques yield a similar success rate via a lateral approach. We also hypothesized that, owing to the peculiar anatomic features of the sciatic nerve at the popliteal level, a single injection via the lateral approach might induce effective anesthesia by targeting the tibial nerve only. METHODS: Ninety-six patients undergoing popliteal sciatic nerve block via a lateral popliteal approach for foot surgery were randomized to receive a single 30-ml injection of ropivacaine 7.5 mg/ml to block the tibial nerve (TN group, n= 32) or the common peroneal nerve (CPN group, n= 32), or two separate 15-ml injections (TN + CPN group, n= 32), after stimulation to evoke motor responses from the target nerves. RESULTS: The mean time to obtain a complete sensory blockade (surgical anesthesia) was shorter in the TN group than in the CPN and TN + CPN groups (14 +/- 7 min vs. 23 +/- 17 and 21 +/- 14 min, respectively; P < 0.05). The success rate was similar in the TN and TN + CPN groups (94%) and, 25 min after the initial injection, was already better in these groups than in the CPN group (94% vs. 75%; P < 0.05). CONCLUSIONS: A lateral popliteal sciatic nerve block obtained with a single 30-ml injection of ropivacaine 7.5 mg/ml after electrostimulation to locate the tibial nerve is as effective as multiple TN + CPN stimulation and injection, and local anesthesia has a significantly shorter onset time.

Ferromagnetic 0-pi junctions as classical spins.

The ground state of highly damped PdNi based 0-pi ferromagnetic Josephson junctions shows a spontaneous half quantum vortex, sustained by a supercurrent of undetermined sign. This supercurrent flows in the electrode of a Josephson junction used as a detector and produces a phi(0)/4 shift in its magnetic diffraction pattern. We have measured the statistics of the positive or the negative sign shift occurring at the superconducting transition of such a junction. The randomness of the shift sign, the reproducibility of its magnitude, and the possibility of achieving exact flux compensation upon field cooling are the features which show that 0-pi junctions behave as classical spins, just as magnetic nanoparticles with uniaxial anisotropy.

Spontaneous supercurrent induced by ferromagnetic pi junctions.

We present magnetization measurements of mesoscopic superconducting niobium loops containing a ferromagnetic (PdNi) pi junction. The loops are prepared on top of the active area of a micro-Hall sensor based on high mobility GaAs/AlGaAs heterostructures. We observe asymmetric switching of the loop between different magnetization states when reversing the sweep direction of the magnetic field. This provides evidence for a spontaneous current induced by the intrinsic phase shift of the pi junction. In addition, the presence of the spontaneous current near zero applied field is directly revealed by an increase of the magnetic moment with decreasing temperature, which results in half integer flux quantization in the loop at low temperatures.

Anesthesiologic aspects of laparoscopic fundoplication for gastroesophageal reflux in children with chronic respiratory and gastroenterological symptoms.

INTRODUCTION: During the past three decades laparoscopy has significantly improved. As fundoplication extensively benefits by the great advantages of the minimally invasive approach, many surgeons chose laparoscopic fundoplication for the treatment of gastroesophageal reflux in adults and children as well. Pneumothorax, cardiovascular collapse, hypoxia, and hypercarbia are some of the anesthesiologist's principal fears during carbon dioxide insufflation. Thus, monitoring cardiovascular and respiratory status is mandatory to early detect any complication and to maintain a proper balance during pneumoperitoneum. MATERIALS AND METHODS: At Gaslini Children's Hospital we performed a prospective nonrandomized study aimed at describing the main cardiorespiratory changes produced by pneumoperitoneum in 33 pediatric patients operated on by laparoscopic fundoplication between January 2000 and June 2001. Patients were divided into two groups; namely, group A and group B. Group A included 14 patients with chronic respiratory symptoms, and group B included 19 children who preoperatively mainly emphasized gastrointestinal symptoms. We monitored intraoperative cardiorespiratory status, timed length of surgery, and described intraoperative complications. RESULTS: No significant cardiovascular changes occurred during carbon dioxide insufflation. Partial oxygen saturation remained still in all the patients. End tidal CO2, meanly higher in group A children, increased in all the patients after pneumoperitoneum creation, but never exceeded 45 mmHg. Similarly, peak inspiratory pressure increased in all the patients, but was always maintained within acceptable values. Finally, group B patients required a harder and slower surgery, whose length seems to be negatively influenced by age. No intraoperative complication occurred. CONCLUSIONS: Carbon dioxide insufflation does not impair cardiovascular function, if intraabdominal pressure is maintained lower than 10 mmHg nor does it interfere with gas exchanges. Pneumoperitoneum slightly reduces ventilatory function, mainly in respiratory patients with various degrees of underlying bronchopulmonary impairments, but this effect is easily correctable. Thus, laparoscopic fundoplication is feasible and safe in both respiratory and gastroenterological patients, although surgery is easier and faster if periesophagitis is less evident.

Ambulatory anesthesia for foot surgery.

Ambulatory surgery has developed extensively over the past few years in most Western countries. The absence of specific legislation in Italy creates a lack of trust in patients and interferes with the development of this discipline. The authors describe their experience in the organisation of an outpatient foot surgery centre over the past thirteen years, which is in constant expansion and currently performs about 300 operations every year. They report the criteria used to select patients, the organisation of the operating theatre, pre- and postoperative treatment and the anesthetic techniques used. Among the latter, they describe a new approach used to block the popliteal sciatic nerve. The results obtained show a high approval rate from the majority of patients treated. The authors attribute this success to a series of factors, including patient selection and surgical procedures, the maintenance of constant standards of quality similar to those in hospitals and the experience of outpatient anesthesia.

Event-related potentials and autonomic functions.

The authors pointed out how some of the anatomic structures involved in the genesis of the event related potentials (ERPs) are also considered parts of the supranuclear regulation apparatus of the autonomic nervous system. Since there are evident functional similarities between some components of the ERPs and the orienting reflex--primitive form of attention--that is clearly associated with an autonomic activation, it could be interesting to evaluate the parameters of the ERPs in those experimental and clinical situations in which there is a functional involvement of the vegetative nervous system.