Publications by authors named "Alessandro Landi"

66 Publications

Quantitative Prediction of the Electro-Mechanical Response in Organic Crystals.

Adv Mater 2021 Mar 17;33(12):e2008049. Epub 2021 Feb 17.

Department of Chemistry, University of Liverpool, Liverpool, L69 3BX, UK.

Organic semiconductors' inherent flexibility makes them appealing for advanced applications such as wearable electronics, e-skins, or pressure sensors, and can even be used to enhance their intrinsic electronic properties. Unfortunately, these applications for organic materials are currently hindered by the lack of a quantitative understanding of the interplay between their electrical and mechanical properties. In this work, this gap is filled by presenting an accurate methodology able to predict quantitatively the effects of external deformation on the charge transport properties of any organic semiconductors. Three prototypical materials are investigated, showing that the experimental variation of charge carrier mobility with strain is fully reproduced, even in a wide range of deformations applied along different crystal axes. The results indicate that the intrinsic electro-mechanical response of the materials varies by orders of magnitude within the class of organic semiconductors, a difference rationalized observing that the mobility trend is primarily influenced by the transfer integrals' variation, rather than by a modification of the crystal phonons. In light of its robustness, accuracy, and low computational cost, this protocol represents an ideal tool to quantify the electro-mechanical response in new organic compounds, thus establishing a reliable route for a full exploitation of strain engineering in advanced technologies.
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http://dx.doi.org/10.1002/adma.202008049DOI Listing
March 2021

Outcome Features Analysis in Intramedullary Tumors of the Cervicomedullary Junction: A Surgical Series.

J Neurol Surg A Cent Eur Neurosurg 2021 May 4;82(3):225-231. Epub 2021 Feb 4.

Department of Neurology and Psychiatry, Endovascular Neurosurgery/Interventional Neuroradiology, "Sapienza" University of Rome, Rome, Italy.

Object:  The aim of this study is to investigate the impact of surgery for different cervicomedullary lesions on symptomatic pattern expression and postoperative outcome. We focused on specific outcome features of the early and late postoperative assessments. The former relies on surgery-related transient and permanent morbidity and feasibility of radicality in eloquent areas, whereas the latter on long-term course in lower grade tumors and benign tumorlike lesions (cavernomas, etc.).

Material And Methods:  We retrospectively analyzed 28 cases of intramedullary tumors of the cervicomedullary junction surgically treated at our institution between 1990 and 2018. All cases were stratified for gender, histology, macroscopic appearance, location, surgical approach, and presence of a plane of dissection (POD). Mean follow-up was 5.6 years and it was performed via periodic magnetic resonance imaging (MRI) and functional assessments (Karnofsky Performance Scale [KPS] and modified McCormick [MC] grading system).

Results:  In all, 78.5% were low-grade tumors (or benign lesions) and 21.5% were high-grade tumors. Sixty-one percent underwent median suboccipital approach, 18% a posterolateral approach, and 21% a posterior cervical approach. Gross total resection was achieved in 54% of cases, near-total resection (>90%) in 14%, and subtotal resection (50-90%) in 32% of cases. Early postoperative morbidity was 25%, but late functional evaluation in 79% of the patients showed KPS > 70 and MC grade I; only 21% of cases showed KPS < 70 and MC grades II and III at late follow-up. Mean overall survival was 7 years in low-grade tumors or cavernomas and 11.7 months in high-grade tumors. Progression-free survival at the end of follow-up was 71% (evaluated mainly on low-grade tumors).

Conclusions:  The surgical goal should be to achieve maximal cytoreduction and minimal postoperative neurologic damage. Functional outcome is influenced by the presence of a POD, radicality, histology, preoperative status, and employment of advanced neuroimaging planning and intraoperative monitoring.
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http://dx.doi.org/10.1055/s-0040-1719080DOI Listing
May 2021

Reliable Predictions of Benzophenone Singlet-Triplet Transition Rates: A Second-Order Cumulant Approach.

J Phys Chem A 2021 Jan 28;125(1):43-49. Epub 2020 Dec 28.

Dipartimento di Chimica e Biologia Adolfo Zambelli, Università di Salerno, Via Giovanni Paolo II, I-84084 Fisciano, SA, Italy.

Fermi golden rule and second-order cumulant expansion of the time-dependent density matrix have been used to compute from first principles the rate of intersystem crossing in benzophenone, using minimum-energy geometries and normal modes of vibrations computed at the TDDFT/CAM-B3LYP level. Both approaches yield reliable values of the S decay rate, the latter being almost in quantitative agreement with the results of time-dependent spectroscopic measurements (0.154 ps observed vs 0.25 ps predicted). The Fermi golden rule slightly overestimates the decay rate of S state ( = 0.45 ps) but provides better insights into the chemico-physical parameters, which govern the transition from a thermally equilibrated population of S, showing that the indirect mechanism is much faster than the direct one because of the vanishingly small Franck-Condon weighted density of states at Δ of transition.
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http://dx.doi.org/10.1021/acs.jpca.0c07848DOI Listing
January 2021

Efficacy of Daptomycin-Containing Regimen for Treatment of Staphylococcal or Enterococcal Vertebral Osteomyelitis: A Prospective Clinical Experience.

Antibiotics (Basel) 2020 Dec 10;9(12). Epub 2020 Dec 10.

Internal Medicine Unit, Policlinico Casilino, 00169 Rome, Italy.

Vertebral osteomyelitis (VO) is a compelling clinical entity for clinicians, because of its insidious and indolent course that makes diagnosis difficult. A concern is reported about the choice of antibiotic regimens, duration of therapy, and criteria to switch to oral therapy. We conducted a prospective observational study. All consecutive hospitalized patients with a confirmed diagnosis of VO caused by staphylococcal or enterococcal strains were analyzed. The primary endpoint was the analysis of clinical cure at the end of therapy. A propensity score for receiving therapy with daptomycin was added to the model. During the study period, 60 episodes of confirmed VO were observed. The main etiology of infection was methicillin-resistant Staphylococcus aureus (29%). Overall, clinical failure at end of therapy was reported in 11 (18.3%) patients. Logistic regression analysis, after propensity score, showed that >2 vertebrae involved (OR 2.4, CI95% 1.12-5.24, = 0.002) and inadequate drainage of infection (OR 4.8, CI95% 2.45-8.51, < 0.001) were independently associated with failure of therapy, while the use of a daptomycin-containing-regimen (OR 0.15, CI 95% 0.04-0.46, < 0.001) with clinical cure. VO caused by staphylococcal or enterococcal strains is associated with an important rate of clinical failure. Daptomycin-containing regimen was strongly associated with clinical cure. Considering that over 70% of VO etiology is caused by Gram-positive strains but the etiology of infection is obtained in about 75% of cases, these data may help physicians to choose the appropriate antibiotic regimen.
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http://dx.doi.org/10.3390/antibiotics9120889DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7764531PMC
December 2020

Fluorescent -type Zn(II) Complexes As Probes for Detecting Hydrogen Sulfide and Its Anion: Bioimaging Applications.

Inorg Chem 2020 Nov 13;59(21):15977-15986. Epub 2020 Oct 13.

Dipartimento di Chimica e Biologia "Adolfo Zambelli", Università degli Studi di Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, Salerno, Italy.

In this work, we investigate the mode of interaction of a family of fluorescent zinc complexes with HS and HS. Different experiments, performed by diverse spectroscopic techniques, provide evidence that HS binds the zinc center of all the complexes under investigation. Treatment with neutral HS exhibits a markedly different reactivity which indicates selectivity for HS over HS of the systems under investigation. Striking color changes, visible to the naked eye, occur when treating the systems with HS or by an HS flow. Accordingly, also the fluorescence is modulated by the presence of HS, with the possible formation of multiple adducts. The results highlight the potential of the devised systems to be implemented as HS/HS colorimetric and fluorescent sensors. Bioimaging experiments indicate the potential of using this class of compounds as probes for the detection of HS in living cells.
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http://dx.doi.org/10.1021/acs.inorgchem.0c02499DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8015222PMC
November 2020

Degenerative Lumbar Spine Stenosis Consensus Conference: the Italian job. Recommendations of the Spinal Section of the Italian Society of Neurosurgery.

J Neurosurg Sci 2021 Apr 24;65(2):91-100. Epub 2020 Sep 24.

Unit of Neurosurgery, San Giovanni Bosco Hospital, Naples, Italy.

In the modern era evidence-based medicine, guidelines and recommendations represent a key-point of daily activity. The Spinal Section of the Italian Society of Neurosurgery introduced some recommendations regarding Degenerative Lumbar Spine Stenosis based on those of the Spine Committee of World Federation of Neurosurgical Societies, revising them on the basis of Italian common practice. In June 2019, a Committee of 21 spine surgeons met in Rome to validate the recommendations of the WFNS. Furthermore, they decided to review the ones that did not reach a consensus to create Italian Recommendations on Degenerative Lumbar Spine Stenosis. A literature review of the last ten years was performed and the statements were voted using the Delphi method. Forty-one statements were discussed, and 7 statements were voted again to reach a consensus with respect to those of the WFNS. A total of 40 statements reached a consensus, of which 36 reached a positive consensus and 4 a negative consensus, while no consensus was reached in 1 case. Conservative multimodal therapy, tailored on the patient, is a reasonable and effective first option choice for the treatment of LSS patients with tolerable moderate symptoms. Surgical treatment is reserved for symptomatic patients non-responding to conservative treatment or with neurological deficits. The best surgical technique to use depends on personal experience; modern MISS techniques are equivalent to open decompressive surgery with some advantages and higher cost-effectiveness. Fusion surgery and mobility preserving surgery only have a marginal role in the treatment of DLSS without instability.
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http://dx.doi.org/10.23736/S0390-5616.20.05042-0DOI Listing
April 2021

Coherent Effects in Charge Transport in Molecular Wires: Toward a Unifying Picture of Long-Range Hole Transfer in DNA.

J Phys Chem Lett 2020 Sep 2;11(18):7769-7775. Epub 2020 Sep 2.

Dipartimento di Chimica e Biologia "A. Zambelli", Università di Salerno, I-84084 Fisciano, Salerno, Italy.

In the framework of a multistep mechanism in which environmental motion triggers comparatively faster elementary electron-transfer steps and stabilizes hole-transfer products, microscopic coherence is crucial for rationalizing the observed yield ratios of oxidative damage to DNA. Interference among probability amplitudes of indistinguishable electron-transfer paths is able to drastically change the final outcome of charge transport, even in DNA oligomers constituted by similar building blocks, and allows for reconciling apparently discordant experimental observations. Properly tailored DNA oligomers appear to be a promising workbench for studying tunneling in the presence of dissipation at the macroscopic level.
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http://dx.doi.org/10.1021/acs.jpclett.0c01996DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8154848PMC
September 2020

Propyne Gas Adsorption in a Cyclic Hexapeptoid: A Combined In Situ XRPD and DFTB Study*.

Chemistry 2020 Nov 6;26(63):14320-14323. Epub 2020 Oct 6.

Department Chemistry and Biology "A. Zambelli", University of Salerno, Via Giovanni Paolo II 132, 84084, Fisciano (SA), Italy.

Cyclic peptoids are macrocyclic N-substituted oligoglycines, with remarkable structural, chemical and physical properties. The gas adsorption properties of a permanently porous hexameric cyclopeptoid decorated with four propargyl and two methoxyethyl side chains were monitored by in situ X-ray powder diffraction (XRPD). High-resolution XRPD data together with Rietveld and density functional based tight binding (DFTB) method allowed us to locate propyne guest molecules inside the host channels, even though the powder sample contains more than one phase. We were able to characterize the host-guest interactions, providing useful information on the host recognition sites and discuss host adaptiveness and host-guest chemical affinity in comparison with analogous compounds.
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http://dx.doi.org/10.1002/chem.202002694DOI Listing
November 2020

The Dynamics of Hole Transfer in DNA.

Molecules 2019 Nov 7;24(22). Epub 2019 Nov 7.

Dipartimento di Chimica e Biologia "A. Zambelli", Università di Salerno, via Giovanni Paolo II, 132, I-84084 Fisciano (SA), Italy.

High-energy radiation and oxidizing agents can ionize DNA. One electron oxidation gives rise to a radical cation whose charge (hole) can migrate through DNA covering several hundreds of Å, eventually leading to irreversible oxidative damage and consequent disease. Understanding the thermodynamic, kinetic and chemical aspects of the hole transport in DNA is important not only for its biological consequences, but also for assessing the properties of DNA in redox sensing or labeling. Furthermore, due to hole migration, DNA could potentially play an important role in nanoelectronics, by acting as both a template and active component. Herein, we review our work on the dynamics of hole transfer in DNA carried out in the last decade. After retrieving the thermodynamic parameters needed to address the dynamics of hole transfer by voltammetric and spectroscopic experiments and quantum chemical computations, we develop a theoretical methodology which allows for a faithful interpretation of the kinetics of the hole transport in DNA and is also capable of taking into account sequence-specific effects.
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http://dx.doi.org/10.3390/molecules24224044DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6891780PMC
November 2019

Prevention of lumbar reherniation by the intraoperative use of a radiofrequency bipolar device: A case-control study.

J Craniovertebr Junction Spine 2019 Apr-Jun;10(2):94-99

Department of Neurology and Psychiatry, Division of Neurosurgery, "Sapienza" University of Rome, Rome, Italy.

Objective: The most common complication after lumbar discectomy is reherniation. Although many studies have investigated factors that may increase the reherniation risk, few are agreed upon all. It has been suggested that limited nucleus removal is associated with higher reherniation risk, while more aggressive nucleus removal can result in increased disc degeneration. Here, we assessed the efficacy of a coblation-assisted microdiscectomy in adult patients undergoing single-level disc surgery.

Methods: We prospectively compared the reherniation rate in 75 patients (Group 1) undergoing single-level lumbar disc surgery completed with the radiofrequency bipolar system Aquamantys (Medtronic, Minneapolis, MN, USA) to that of a historical control group ( = 75) matched for variables related to herniation level and characteristics (Group 2). Patients were followed up to 4 years. Reherniations were assessed, pain and function were monitored throughout, and imaging was performed at annual follow-up.

Results: The overall symptomatic reherniation rate was 4%. In particular, one case (1.3%) was observed in Group 1 and five (6.7%) in Group 2 ( < 0.05). Magnetic resonance imaging identified a total of 4 (2.7%) asymptomatic reherniations at 12 months, 6 (4%) at 24 and 36 months, and 7 (4.7%) at 48 months. Overall, Group 1 contained one (1.3%) asymptomatic reherniation case, while six (8%) were observed in Group 2 ( < 0.05).

Conclusions: The low reherniation rate in patients treated by the coblation-assisted microdiscectomy suggests that this technique may reduce the reherniation risk. Clinical outcomes for pain and function at 4 years follow-up compared favorably with literature data. Randomized controlled trial could confirm these results.
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http://dx.doi.org/10.4103/jcvjs.JCVJS_47_19DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6652257PMC
August 2019

Long-Term Efficacy of Shunt Therapy in Idiopathic Normal Pressure Hydrocephalus.

World Neurosurg 2019 Sep 30;129:e458-e463. Epub 2019 May 30.

Division of Neurosurgery, Department of Neurology and Psychiatry, La Sapienza University of Rome, Rome, Italy.

Background: Idiopathic normal pressure hydrocephalus (iNPH) is one of the very few treatable types of dementia. Shunt therapy has been shown to be effective in improving symptoms. However, the long-term results of cerebrospinal fluid diversion are variable. The aim of this retrospective study was to investigate long-term outcomes of patients with idiopathic normal pressure hydrocephalus treated with ventriculoperitoneal shunt by using programmable valves.

Methods: Symptoms before treatment were recorded. Clinical symptoms and outcome after ventriculoperitoneal shunt were assessed based on changes in gait, urinary incontinence, and cognitive dysfunction at yearly follow-up spanning at least 10 years.

Results: Among 50 patients treated, 5 had died at the time of the evaluation. Median age was 71 years, and mean follow-up time of the surviving patients was 120.2 ± 2.3 years. Overall, there was a significant and lasting improvement among all symptoms compared with the baseline (P < 0.05). Gait showed better and sustained improvement compared with the baseline (P < 0.05). Cognitive impairment and urinary incontinence improved in the early follow-up (P < 0.05) followed by declines in long-term follow-up. Ten patients (20%) required surgical revisions for shunt malfunction. Change in valve pressure was performed in 20 patients (40%). Overall, 93.3% revisions resulted in clinical improvement.

Conclusions: Surgical treatment for idiopathic normal pressure hydrocephalus by ventriculoperitoneal shunt is a safe modality that improves symptoms in most patients, including in the long-term. Strict follow-up is necessary for early diagnosis of shunt malfunction or need for valve adjustment.
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http://dx.doi.org/10.1016/j.wneu.2019.05.183DOI Listing
September 2019

Treatment algorithm for spontaneous spinal infections: A review of the literature.

J Craniovertebr Junction Spine 2019 Jan-Mar;10(1):3-9

Department of Human Neurosciences, Division of Neurosurgery, Sapienza University of Rome, Rome, Italy.

Background: Primary spinal infections are rare pathologies with an estimated incidence of 5% of all osteomyelitis. The diagnosis can be challenging and this might result in a late identification. The etiological diagnosis is the primary concern to determine the most appropriate treatment. The aim of this review article was to identify the importance of a methodological attitude toward accurate and prompt diagnosis using an algorithm to aid on spinal infection management.

Methods: A search was done on spinal infection in some databases including PubMed, ISI Web of Knowledge, Google Scholar, Ebsco, Embasco, and Scopus.

Results: Literature reveals that on the basis of a clinical suspicion, the diagnosis can be formulated with a rational use of physical, radiological, and microbiological examinations. Microbiological culture samples can be obtained by a percutaneous computed tomography-guided procedure or by an open surgical biopsy. When possible, the samples should be harvested before antibiotic treatment is started. Indications for surgical treatment include neurological deficits or sepsis, spine instability and/or deformity, presence of epidural abscess and failure of conservative treatment.

Conclusion: A multidisciplinary approach involving both a spinal surgeon and an infectious disease specialist is necessary to better define the treatment strategy. Based on literature findings, a treatment algorithm for the diagnosis and management of primary spinal infections is proposed.
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http://dx.doi.org/10.4103/jcvjs.JCVJS_115_18DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6469318PMC
April 2019

Transient and Enduring Electronic Resonances Drive Coherent Long Distance Charge Transport in Molecular Wires.

J Phys Chem Lett 2019 Apr 4;10(8):1845-1851. Epub 2019 Apr 4.

Dipartimento di Chimica e Biologia , Università di Salerno , I-84084 Fisciano , Salerno , Italy.

It is shown that the yields of oxidative damage observed in double-stranded DNA oligomers consisting of two guanines separated by adenine-thymine (A:T) bridges of various lengths are reliably accounted for by a multistep mechanism, in which transient and nontransient electronic resonances induce charge transport and solvent relaxation stabilizes the hole transfer products. The proposed multistep mechanism leads to results in excellent agreement with the observed yield ratios for both the short and the long distance regime; the almost distance independence of yield ratios for longer bridges ( n ≥ 3) is the consequence of the significant energy decrease of the electronic levels of the bridge, which, as the bridge length increases, become quasi-degenerate with those of the acceptor and donor groups (enduring resonance). These results provide significant guidelines for the design of novel DNA sequences to be employed in organic electronics.
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http://dx.doi.org/10.1021/acs.jpclett.9b00650DOI Listing
April 2019

Recurrent lumbar disc herniation: Is there a correlation with the surgical technique? A multivariate analysis.

J Craniovertebr Junction Spine 2018 Oct-Dec;9(4):260-266

Department of Neurology and Psychiatry, Division of Neurosurgery, "Sapienza" University of Rome, Rome, Italy.

Purpose: The recurrence of a lumbar disc herniation (LDH) is a common cause of poor outcome following lumbar discectomy. The aim of this study was to assess a potential relationship between the incidence of recurrent LDH and the surgical technique used. Furthermore, we tried to define the best surgical technique for the treatment of recurrent LDH to limit subsequent recurrences.

Materials And Methods: A retrospective study was conducted on 979 consecutive patients treated for LDH. A multivariate analysis tried to identify a possible correlation between (1) the surgical technique used to treat the primary LDH and its recurrence; (2) technique used to treat the recurrence of LDH and the second recurrence; and (3) incidence of recurrence and clinical outcome. Data were analyzed with the Pearson's Chi-square test for its significance.

Results: In 582 cases (59.4%), a discectomy was performed, while in 381 (40.6%), a herniectomy was undertaken. In 16 cases, a procedure marked as "other" was performed. Among all patients, 110 (11.2%) had a recurrence. Recurrent LDH was observed in 55 patients following discectomy (9.45%), in 45 following herniectomy (11.8%), and in 10 (62.5%) following other surgery. Our data showed that 90.5% of discectomies and 88.2% of the herniectomies had a good clinical outcome, whereas other surgeries presented a recurrence rate of 62.5% (Pearson's χ< 0.001). No statistical differences were observed between discectomy or herniectomy, for the treatment of the recurrence, and the incidence for the second recurrences ( > 0.05). A significant statistical correlation emerged between the use of other techniques and the incidence for the second recurrences ( < 0.05).

Conclusions: The recurrence of an LDH is one of the most feared complications following surgery. Although the standard discectomy has been considered more protective toward the recurrence compared to herniectomy, our data suggest that there is no significant correlation between the surgical technique and the risk of LDH recurrence.
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http://dx.doi.org/10.4103/jcvjs.JCVJS_94_18DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6364357PMC
February 2019

Chiari Malformations.

Acta Neurochir Suppl 2019;125:89-95

Department of Neurology and Psychiatry, Division of Neurosurgery, "Sapienza" University of Rome, Rome, Italy.

Background: Chiari malformations (CM) represent a group of anomalies characterized by descent of the cerebellar tonsils or vermis into the cervical spinal canal. These malformations can be associated with abnormalities such as hydrocephalus, spina bifida, hydromyelia, syringomyelia, curvature of the spine (kyphosis and scoliosis) and tethered cord syndrome. Hereditary syndromes and other disorders that affect growth and bone formation-such as craniosynostosis, Ehlers-Danlos syndromes and Klippel-Feil syndrome-can also be associated with CM.

Methods: The literature concerning treatment is large, and an extensive range of therapeutic protocols have been described. The literature is inclined in favour of surgery; however, there is controversy over when to perform surgery and which procedure is most appropriate. Lately, the indications for stabilization have been under discussion.

Results And Conclusion: In this paper we review the literature and discuss the historical background, anatomical forms, pathophysiology, clinical presentation, relationships with other diseases and diagnostic procedures for these abnormalities.
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http://dx.doi.org/10.1007/978-3-319-62515-7_13DOI Listing
August 2019

Long-term clinical and radiological outcomes following anterior cervical discectomy and fusion by zero-profile anchored cage.

J Craniovertebr Junction Spine 2018 Apr-Jun;9(2):87-92

Department of Neurology and Psychiatry, Neurosurgery, Sapienza University of Rome, Rome, Italy.

Objectives: The purpose of this study was to extend the results of our previous study providing a minimum of 4-year follow-up results of a prospective study following implantation of a cervical cage with an integrated fixation system.

Summary Of Background Data: The use of cervical intersomatic cages with an integrated fixation system for anterior cervical discectomy and fusion (ACDF) has increased rapidly in this last decade. In addition to immediate stabilization, these implants allow avoidance of anterior plating and iliac crest bone-grafting.

Methods: Patients were studied prospectively, and data were collected and analyzed. Intersomatic cages with an integrated fixation system were used in consecutive 100 patients operated on for ACDF. Intraoperative parameters, clinical, and outcome scores were recorded. Radiographs were taken to evaluate implant positioning and fusion rate, disc height (DH), and changes in adjacent disc spaces. All the patients had a minimum 4-year follow-up.

Results: A total of 127 cages were implanted in the 100 patients. Compared to preoperatively, the visual analog scale, 36-item short-form health survey, the Japanese Orthopedic Association, and the Neck Disability Index scores were significantly improved at 1-year follow-up without change during subsequent follow-up. At 4 years, the fusion rate was 97%. Two patients complained about minor dysphagia-related symptoms, which resolved rapidly. DH index and cervical Cobb angle were significantly restored after surgery, and the results were maintained during the whole follow-up.

Conclusions: This is a prospective, independently conducted study on cages with an integrated fixation system with 4-year long follow-up. Findings of this study seem to be interesting regarding outcomes and low complications rates compared to recent series using other implants with integrated fixation system. Larger, randomized controlled trials are warranted.
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http://dx.doi.org/10.4103/jcvjs.JCVJS_36_18DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6024738PMC
July 2018

Prognostic Factors in Clival Chordomas: An Integrated Analysis of 347 Patients.

World Neurosurg 2018 Oct 30;118:e375-e387. Epub 2018 Jun 30.

Department of Neurology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China. Electronic address:

Objective: To investigate prognostic factors of clival chordoma using the largest patient set to date.

Methods: Appropriate studies were identified per search criteria, data satisfying criteria were extracted, and survival analysis was performed to investigate prognostic factors of clival chordoma.

Results: A total of 347 patients from the literature cohort met our inclusion criteria. Of 346 cases in which extent of resection was reported, gross total resection (GTR), subtotal resection, and biopsy were achieved in 118 (34.1%), 205 (59.2%), and 21 (6.1%) cases, respectively. Two (0.6%) subjects did not undergo surgery. Of 185 cases in which surgical approach was reported, 56 (30.3%) underwent an endoscopic transoral approach, 17 (9.2%) microscopic transsphenoidal, 45 (24.3%) endoscopic or microscopic, 45 (24.3%) craniotomy, and 22 (11.9%) other approaches. There was no significant difference in GTR rates of different surgical approaches (P = 0.101). Median follow-up was 46.6 months. The 5- and 10-year rates for progression-free survival (PFS) were 59.2% and 47.9%, respectively. The 5- and 10-year rates for overall survival (OS) were 77.3% and 63.9%, respectively. On multivariate analysis for both PFS and OS, GTR demonstrated significantly improved outcomes when compared with subtotal resection (hazard ratio 0.45, 95% confidence interval 0.22-0.90, P = 0.025 for PFS; hazard ratio 0.20, confidence interval 0.06-0.65, P = 0.008 for OS).

Conclusions: GTR rates were comparable in different surgical approaches. GTR was a significant predictor of longer PFS and OS in clival chordoma.
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http://dx.doi.org/10.1016/j.wneu.2018.06.194DOI Listing
October 2018

Isolated Pediatric Intramedullary Schwannoma: Case Report and Review of Literature.

World Neurosurg 2018 Jul 9;115:417-420. Epub 2018 May 9.

Division of Neurosurgery A, Department of Neurology and Psychiatry, Sapienza University of Rome, Rome, Italy.

Background: Intramedullary (IM) schwannomas are rare entities representing 0.3%-1% of intramedullary tumors and 1.1% of spinal schwannomas. Beside many theories proposed, their rare occurrence might be related to the absence of Schwann cells in the spinal cord. Pediatric IM schwannomas are uncommon, and in the absence of neurofibromatosis they are extremely rare. To date, few cases have been reported in the literature.

Case Description: We describe the case of an 8-year-old female affected by a progressive paraparesis. Neuroradiologic investigations showed an oval-shaped mass at the level of T10-T11. The patient underwent surgery, performed under neurophysiologic monitoring. The patient was operated on with complete removal of the lesion. The postoperative course was uneventful.

Conclusions: The clinical, neuroradiologic, and intraoperative findings are presented, along with a review of the literature. Despite the number of lesions potentially compressing the spinal cord, IM schwannoma is rare but should be taken into account in the differential diagnosis.
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http://dx.doi.org/10.1016/j.wneu.2018.04.220DOI Listing
July 2018

Opening New Window in Upper Clival Region: Results from Anatomic Study.

World Neurosurg 2018 05 21;113:140-141. Epub 2018 Feb 21.

Department of Neurology and Psychiatry, Neurosurgery, "Sapienza" University of Rome, Italy.

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http://dx.doi.org/10.1016/j.wneu.2018.02.065DOI Listing
May 2018

Hole Hopping Rates in Organic Semiconductors: A Second-Order Cumulant Approach.

J Chem Theory Comput 2018 Mar 5;14(3):1594-1601. Epub 2018 Feb 5.

Dipartimento di Chimica e Biologia "A. Zambelli" , Università di Salerno , Via Giovanni Paolo II , I-84084 Fisciano (SA) , Italy.

Second-order cumulant expansion of the time dependent reduced density matrix has been employed to evaluate hole hopping rates in pentacene, tetracene, picene, and rubrene homodimers. The cumulant expansion is a full quantum mechanical approach, which enables the use of the whole set of nuclear coordinates in computations and the inclusion of both the effects of the equilibrium position displacements and of normal mode mixing upon hole transfer. The time dependent populations predicted by cumulant approach are in good agreement with those obtained by numerical solution of time dependent Schrödinger equation, even for ultrafast processes, where the Fermi Golden Rule fails.
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http://dx.doi.org/10.1021/acs.jctc.7b00858DOI Listing
March 2018

Spontaneous Spinal Discitis and Spondylodiscitis: Clinicotherapeutic Remarks.

J Neurosci Rural Pract 2017 Oct-Dec;8(4):642-646

Department of Neurology and Psychiatry, Division of Neurosurgery, Sapienza University of Rome, Rome, Italy.

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http://dx.doi.org/10.4103/jnrp.jnrp_67_17DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5709891PMC
December 2017

Prognostic Factors and Treatment of Spinal Astrocytomas: A Multi-institutional Cohort Analysis.

Spine (Phila Pa 1976) 2018 05;43(10):E565-E573

Department of Neurology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China.

Study Design: Retrospective cohort analysis of patients with spinal astrocytoma from multi-institutional data and the literature.

Objective: To determine the prognostic factors, treatment, and survival of patients.

Summary Of Background Data: Our current understanding of the epidemiology, prognosis, and optimal treatment of spinal astrocytoma is limited. The literature is confined to case reports or small institutional case series.

Method: Patient demographics, tumor characteristics, treatments, and outcomes were extracted. Univariate Kaplan-Meier survival analysis was performed to identify prognostic factors followed by multivariate Cox proportional hazard analysis. Wilcoxon signed-rank test was performed on pre- and postoperational functional status as measured by McCormick score.

Results: Ninety-four patients from four institutions and 339 patients from the literature were included. For the multi-institutional cohort, WHO grade IV tumors had shorter progression-free survival (PFS) than those of lower grades, whereas gross total resection (GTR) (hazard ratio [HR]: 0.41, 95% confidence interval [CI]: 0.14-1.27, P = 0.124) trended toward longer PFS when compared to subtotal resection (STR). Age 18 years or older, paresthesia as a presenting symptom, and higher WHO grade were associated with shorter overall survival (OS), whereas thoracic tumor location when compared to cervical tumor location, biopsy when compared to STR, and radiotherapy (HR: 0.42, 95% CI: 0.20-0.88, P = 0.022) were associated with longer OS. For the literature cohort, GTR (HR 0.43, 95% CI: 0.24-0.77, P = 0.005) was associated with longer PFS when compared to STR, whereas higher WHO grade was associated with shorter PFS. Higher WHO grade and recurrence/progression were associated with shorter OS. Postoperative McCormick score was significantly higher than preoperative score (P < 0.001), but subgroup analysis of the change in McCormick score by extent of resection revealed no differences among groups (P = 0.551).

Conclusion: In patients with spinal astrocytomas, GTR likely resulted in longer PFS when compared to STR. Adjuvant radiotherapy appears to be effective in improving survival outcomes for high-grade tumors.

Level Of Evidence: 4.
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http://dx.doi.org/10.1097/BRS.0000000000002485DOI Listing
May 2018

Spinal Nerves Schwannomas: Experience on 367 Cases-Historic Overview on How Clinical, Radiological, and Surgical Practices Have Changed over a Course of 60 Years.

Neurol Res Int 2017 18;2017:3568359. Epub 2017 Sep 18.

Department of Neurological Sciences, Neurosurgery, University of Rome "Sapienza", Rome, Italy.

Background: Spinal schwannomas are common benign spinal tumors. Their treatment has significantly evolved over the years, and preserving neurological functions has become one of the main treatment goals together with tumor resection.

Study Design And Aims: Retrospective review focused on clinical assessment, treatment techniques, and outcomes.

Methods: A retrospective study on our surgical series was performed. Clinical and operative data were analyzed. In regard to neurophysiologic monitoring, patients were retrospectively divided into two groups comparing the outcomes before and after introduction of routine intraoperative neurophysiology tests.

Results: From 1951 to 2010, 367 patients overall were treated. Diagnosis was obtained using angiography and/or myelography (pre-CT era), MRI, or CT scan. A posterior spinal approach was used for most patients; complex approaches were adopted for treatment of giant/dumbbell tumors. A trend of neurophysiology monitoring decreasing the rate of post-op neurological deficits was observed but was not statistically significant enough to draft evidence-based conclusions.

Conclusions: Clinical and radiological assessment of spinal schwannomas has markedly changed over the course of 50 years. Diagnostic tools have improved, and detection of recurrence has become way more sensitive. Neurophysiologic monitoring has become a useful intraoperative tool to guide resection and prevent post-op neurological impairment.
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http://dx.doi.org/10.1155/2017/3568359DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5624174PMC
September 2017

Preliminary experience with lumbar facet distraction and fixation as treatment for lumbar spinal stenosis.

J Craniovertebr Junction Spine 2017 Jul-Sep;8(3):193-198

Department of Neurology and Psychiatry, Division of Neurosurgery A, Sapienza University of Rome, Rome, Italy.

Objectives: To assess the properties of facet fixation with the Facet Wedge system in patients affected by lumbar spinal stenosis (LSS).

Summary Of Background Data: Implant of intra-articular spacers is an emerging technique for lumbar degenerative disease.

Methods: This study included forty patients (Group 1) with symptomatic LSS in whom intra-articular spacers have been implanted along with microdecompression (MD) of the neural structures. Group 1 has been compared with a homogeneous group of patients with LSS treated with MD without intra-articular spacers implant (Group 2). Clinical findings have been observed preoperatively and 3, 6, 12 months postoperatively using dedicated questionnaires (Zurich Claudication Questionnaire, visual analog scale, and Oswestry disability index).

Results: One year following surgical treatment, 87% of the patients presented with good improvement of symptoms and 97% referred satisfaction for surgery. Overall, patients of Group 1 presented with significantly better clinical outcome when compared with the control group ( < 0.01).

Conclusions: Intra-articular spacers showed significant and clinically meaningful improvements in pain and disability for up to 1 year. These findings need further studies and a longer follow-up.
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http://dx.doi.org/10.4103/jcvjs.JCVJS_56_17DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5634105PMC
October 2017

Introducing the concept of "CSF-shift edema" in traumatic brain injury.

J Neurosci Res 2018 04 24;96(4):744-752. Epub 2017 Aug 24.

Neurosurgical Clinic, Department of Experimental Biomedicine & Clinical Neurosciences, University of Palermo, Italy.

Brain edema after severe traumatic brain injury (TBI) plays an important role in the outcome and survival of injured patients. It is also one of the main targets in the therapeutic approach in the current clinical practice. To date, the pathophysiology of traumatic brain swelling is complex and, being that it is thought to be mainly cytotoxic and vasogenic in origin, not yet entirely understood. However, based on new understandings of the hydrodynamic aspects of cerebrospinal fluid (CSF), an additional mechanism of brain swelling can be considered. An increase in pressure into the subarachnoid space, secondary to traumatic subarachnoid hemorrhage, would result in a rapid shift of CSF from the cisterns, through the paravascular spaces, into the brain, resulting in an increase of brain water content. This mechanism of brain swelling would be termed as "CSF-shift edema." This "CSF-shift," promoted by a pressure gradient, leads to increased pressure inside the paravascular spaces and the interstitium of the brain, disturbing the functions of the paravascular system, with implications of secondary brain injury. Cisternostomy, an emerging surgical treatment, would reverse the direction of the CSF-shift, allowing for a decrease in brain swelling. In addition, this technique would reduce the pressure in the paravascular spaces and interstitium, leading to a recovery of the functionality of the paravascular system.
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http://dx.doi.org/10.1002/jnr.24145DOI Listing
April 2018

Comment on "Controversies about Interspinous Process Devices in the Treatment of Degenerative Lumbar Spine Diseases: Past, Present, and Future".

Biomed Res Int 2017 11;2017:6545361. Epub 2017 May 11.

Department of Neurology and Psychiatry, Division of Neurosurgery A, Sapienza University of Rome, Rome, Italy.

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http://dx.doi.org/10.1155/2017/6545361DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5444032PMC
November 2018

Modeling DNA oxidation in water.

Phys Chem Chem Phys 2017 May;19(21):13571-13578

Dipartimento di Chimica e Biologia "Adolfo Zambelli", Università di Salerno, I-84084 Fisciano (SA), Italy.

A novel set of hole-site energies and electronic coupling parameters to be used, in the framework of the simplest tight-binding approximation, for predicting DNA hole trapping efficiencies and rates of hole transport in oxidized DNA is proposed. The novel parameters, significantly different from those previously reported in the literature, have been inferred from reliable density functional calculations, including both the sugar-phosphate ionic backbone and the effects of the aqueous environment. It is shown that most of the experimental oxidation free energies of DNA tracts and of oligonucleotides available from photoelectron spectroscopy and voltammetric measurements are reproduced with great accuracy, without the need for introducing sequence dependent parameters.
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http://dx.doi.org/10.1039/c7cp02029eDOI Listing
May 2017

Multimodal Intraoperative Neuromonitoring in Aneurysm Surgery.

World Neurosurg 2017 05 3;101:763-765. Epub 2017 Mar 3.

Department of Neurosurgery, University of Messina, Messina, Italy.

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http://dx.doi.org/10.1016/j.wneu.2017.02.103DOI Listing
May 2017

Lumbar Annular Tear in the Absence of Nerve Root Compression: Is Discectomy Useful?

J Neurosci Rural Pract 2016 Dec;7(Suppl 1):S126-S128

Department of Neurology and Psychiatry, Neurosurgical Division, University of Rome "Sapienza" Policlinico Umberto I, Rome, Italy.

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http://dx.doi.org/10.4103/0976-3147.196449DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5244047PMC
December 2016

Correlation Between Timing of Surgery and Outcome in ThoracoLumbar Fractures: Does Early Surgery Influence Neurological Recovery and Functional Restoration? A Multivariate Analysis of Results in Our Experience.

Acta Neurochir Suppl 2017 ;124:231-238

Department of Neurology and Psychiatry, Division of Neurosurgery, "Sapienza" University of Rome, Viale del Policlinico 155, 00161, Rome, Italy.

Background: Treatment for spinal trauma is affected by both nonmodifiable and modifiable variables. The aim of this study was to compare early surgery with intermediate and late surgery to determine the benefits of spinal reconstruction in neurological recovery and functional restoration in patients with thoracolumbar fractures.

Methods: In order to identify correlations between treatment timing, fracture site, neurological recovery, American Spinal Injury Association (ASIA) score restoration, and rehabilitation prognosis in patients with thoracic and lumbar fractures, we conducted a multivariate analysis of the results of surgery, at our institution, in 166 consecutive patients with unstable thoracolumbar fractures with or without neurological impairment. We conducted a literature review (1988-2012) and compared our results with those already published.

Results: Regardless of the location and type of fracture, early surgery resulted in a reduction of median hospital and intensive care unit (ICU) length of stay, as well as a reduction of nosocomial complications. Regardless of the type of fracture and preoperative ASIA score, thoracic fractures had the worst outcome. Early treatment seemed to have better results, depending on the preoperative ASIA score.

Conclusion: Early surgery in patients with thoracolumbar fractures with incomplete neurological damage could positively affect neurological recovery, functional restoration, length of hospital and ICU stay, and associated comorbidity. Thoracic fractures had the worst outcome. Early surgery seemed to have better results if the initial ASIA score was good. The better the ASIA score on admission, the better was the outcome. Surgical timing did not affect the outcome when the ASIA score was A or E.
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http://dx.doi.org/10.1007/978-3-319-39546-3_35DOI Listing
November 2017