Cochlear implantation in single-sided deafness: a single-center experience of 138 cases

OBJECTIVES

Assess the outcomes in patients who underwent cochlear implant (CI) for single-sided deafness (SSD).

METHODS

All patients affected by SSD who underwent CI at Gruppo Otologico, Piacenza, from October 2012 to May 2022 with at least 6 months of follow-up were selected in the study group. The analysis included subjective and objective measures performed pre-operative and up to 24 months after surgery. Hearing threshold on both sides was evaluated with a weighted four-frequency average (PTA [0.5 kHz + 1 kHz + 2 kHz + 4 kHz]/4) on pure tone audiometry and speech audiometry (Speech Discrimination Score, SDS). The Speech Spatial and Qualities of Hearing scale (SSQ Questionnaire) for binaural hearing benefits and sound localization, the Tinnitus Handicap Inventory Questionnaire (THI) and Dizziness Handicap Inventory Questionnaire (DHI) were used for subjective assessment.

RESULTS

Data from 138 patients, 69 males and 69 females, (mean age 49 years, range 17-77 years) underwent CI for SSD were examined. Single-sided hearing deprivation average before undergoing CI surgery was 2.5 years (range 3 months-35 years). There was a significant reduction of THI and DHI scores compared to pre-operative scores alongside a referred improvement in social, physical, and emotional well-being through the SSQ questionnaire.

CONCLUSIONS

To the best of our knowledge, this paper descried the largest cohort of SSD who underwent CI in a single institution. According to our findings CI in patients affected by SSD represents a valuable tool for an overall improvement of tinnitus and dizziness but also quality of life, after at least 6 months of follow-up. Further studies are desirable to improve rehabilitation pathways and possibly set new standards of care of this condition.

Quality Evaluation of Fresh Pasta Fortified with Sourdough Containing Wheat Germ and Wholemeal Semolina

Pasta is a staple food in the Mediterranean diet, primarily manufactured with two essential ingredients, semolina and water; nowadays, it is often supplemented with functional ingredients. In this work, a sourdough obtained with wheat germ and wholemeal semolina was used, in order to improve sensorial and nutritional properties of fresh pasta, to prevent lipids oxidation, and to improve the shelf life. Three different formulations were prepared, a first one using semolina, a second one with raw wheat germ, wholemeal semolina, and semolina, and the last one with semolina and sourdough. The study highlighted the improved nutritional properties of pasta with sourdough (reduced phytic acid content, higher antioxidant activity and phenolic content). Proteins, ashes, dietary fibers, lipids, and tocols (vitamin E) increased in pasta with wheat germ and wholemeal semolina, and with sourdough. The amount of tocols decreased in pasta samples after cooking, except for the β-tocopherol in sourdough pasta, the amount of which remained high, surprisingly. Lipase and lipoxygenase enzymes likely decreased as an effect of the pasteurization process. The NMR analysis showed that lipid oxidation was higher in semolina pasta than in pasta with wheat germ, most likely due to the protective effect of antioxidants deriving from wheat germ.

From Hop to Beer: Influence of Different Organic Foliar Fertilisation Treatments on Hop Oil Profile and Derived Beers' Flavour

Foliar fertilisation is known to influence the physiological response of Humulus lupulus (hop plants), but its effect on the flavour profile of beer still has to be investigated. By comparing the effects of four fertilisation treatments, this study aims at determining whether different foliar fertilisation treatments have a significant impact on hop plants' aromatic quality and that of the beer produced. Hop cones harvested from each experimental treatment were brewed to obtain five single dry-hopped beers, which were subsequently analysed. Gas chromatography-mass spectrometry (GC-MS) and electronic nose (Cyranose 320) analyses were performed on the hop cones, while headspace solid-phase microextraction-gas chromatography-mass spectrometry HS-SPME-GC-MS, electronic nose and sensory analyses were carried out on the beers produced. The analyses not only allowed for a differentiation between the hops from the four fertilisation treatments and the control but also enabled a differentiation between the beers produced for their identification. Sensory evaluation revealed consumer preferences regarding the dry-hopped beers analysed, evidencing their distinctive features, including significant differences in both aroma and flavour.

In Vivo and In Vitro Starch Digestibility of Fresh Pasta Produced Using Semolina-Based or Wholemeal Semolina-Based Liquid Sourdough

The use of wholemeal flour and sourdough fermentation in different food matrices has received considerable attention in recent years due to its resulting health benefits. In this study, a semolina-based and a wholemeal semolina-based sourdough were prepared and added to the formulation of gnocchetti-type fresh pasta. Four types of gnocchetti were made, using semolina plus semolina-based sourdough (SS), semolina plus wholemeal semolina-based sourdough (SWS), semolina alone (S), and semolina plus wholemeal semolina (WS). The latter two were used as controls. The digestibility of starch was studied both in vitro and in vivo, and the glycemic response (GR) and glycemic load (GL) were determined. Starch digestibility, both in vivo and in vitro, was higher in wholemeal semolina than semolina pasta and the resulting GR values (mg dL⁻¹ min⁻¹) were also higher (2209 and 2277 for WS and SWS; 1584 and 1553 for S and SS, respectively). The use of sourdough significantly reduced the rapidly digestible starch (RDS) content and increased the inaccessible digestible starch (IDS) content. The addition of sourdough to the formulation had no effect on the GR values, but led to a reduction of the GL of the pasta. These are the first data on the GR and GL of fresh pasta made with sourdough.

Surgery of the lateral skull base: a 50-year endeavour

Disregarding the widely used division of skull base into anterior and lateral, since the skull base should be conceived as a single anatomic structure, it was to our convenience to group all those approaches that run from the antero-lateral, pure lateral and postero-lateral side of the skull base as “Surgery of the lateral skull base”. “50 years of endeavour” points to the great effort which has been made over the last decades, when more and more difficult surgeries were performed by reducing morbidity. The principle of lateral skull base surgery, “remove skull base bone to approach the base itself and the adjacent sites of the endo-esocranium”, was then combined with function preservation and with tailoring surgery to the pathology. The concept that histology dictates the extent of resection, balancing the intrinsic morbidity of each approach was the object of the first section of the present report. The main surgical approaches were described in the second section and were conceived not as a step-by-step description of technique, but as the highlighthening of the surgical principles. The third section was centered on open issues related to the tumor and its treatment. The topic of vestibular schwannoma was investigated with the current debate on observation, hearing preservation surgery, hearing rehabilitation, radiotherapy and the recent efforts to detect biological markers able to predict tumor growth. Jugular foramen paragangliomas were treated in the frame of radical or partial surgery, radiotherapy, partial “tailored” surgery and observation. Surgery on meningioma was debated from the point of view of the neurosurgeon and of the otologist. Endolymphatic sac tumors and malignant tumors of the external auditory canal were also treated, as well as chordomas, chondrosarcomas and petrous bone cholesteatomas. Finally, the fourth section focused on free-choice topics which were assigned to aknowledged experts. The aim of this work was attempting to report the state of the art of the lateral skull base surgery after 50 years of hard work and, above all, to raise questions on those issues which still need an answer, as to allow progress in knowledge through sharing of various experiences. At the end of the reading, if more doubts remain rather than certainties, the aim of this work will probably be achieved.

Fresh Pasta Manufactured with Fermented Whole Wheat Semolina: Physicochemical, Sensorial, and Nutritional Properties

Fresh pasta (SP) was prepared by mixing semolina with liquid sourdough, whole wheat semolina based, and the effects of sourdough inclusion were evaluated against a control sample (CP) prepared using semolina and whole wheat semolina. Physicochemical, nutritional, and sensorial analyses were performed on pasteurized fresh pasta, before and after cooking. The optimum cooking time was not affected by whole wheat sourdough, whereas differences were found in color, firmness, and cooking loss. Changes of in vitro digested starch fractions in SP pasta were affected by a higher cooking loss. Overall, SP samples were characterized by improved nutraceutical features, namely higher content of free essential amino acids and phenolic compounds, lower phytic acid content, and higher antioxidant activity. Sensory analyses (acceptability and check-all-that-apply (CATA) tests) showed significantly higher scores for the SP, and the differences were enhanced when the consumers were informed about the product composition and how it was manufactured. Consumers checked for more positive sensory parameters for the SP than the CP.

Filament identification in wide-angle high speed imaging of the mega amp spherical tokamak

A new tomographic inversion technique is presented for the identification of plasma filaments in wide-angle visible camera data. The technique works on the assumption that background subtracted images of filaments can be represented as a superposition of uniformly emitting magnetic equilibrium field lines. A large collection of equilibrium magnetic field lines is traced and projected onto the camera field of view and combined to form a geometry matrix describing the coordinate transformation from magnetic field aligned coordinates to image pixel coordinates. Inverting this matrix enables the reprojection of the emission in the camera images onto a field aligned basis, from which filaments are readily identifiable. The inversion is a poorly conditioned problem which is overcome using a least-squares approach with Laplacian regularization. Blobs are identified using the "watershed" algorithm and 2D Gaussians are fitted to get the positions, widths, and amplitudes of the filaments. A synthetic camera diagnostic generating images containing experimentally representative filaments is utilized to rigorously benchmark the accuracy and reliability of the technique. 74% of synthetic filaments above the detection amplitude threshold are successfully detected, with 98.8% of detected filaments being true positives. The accuracy with which filament properties and their probability density functions are recovered is discussed, along with sources of error and methods to minimize them.

Effect of liquid sourdough technology on the pre-biotic, texture, and sensory properties of a crispy flatbread

The present study compared liquid sourdough technology with baker's yeast leavening when applied to the production of a semolina-based crispy flatbread. Following in vitro starch digestion, the results revealed the sourdough leavened flatbread to contain a lower percentage of rapidly digestible starch (16%), higher amounts of slowly digestible starch (27%) and inaccessible digestible starch (4.1%) compared with the baker's yeast leavened flatbread (20, 20, and 2.4%, respectively), making the former nutritionally healthier. The sourdough leavened bread was crispier, stiffer and more solid, as shown by texture analyses, although Raman spectroscopy revealed no differences in the crystallinity status of starch. The descriptive analyses show that the use of sourdough enhances the positive sensory traits, as rated by the consumer panel scores (6.08 vs. 5.56). In summary, the results indicate that the implementation of sourdough technology in the production of flat crispy breads could confer economic advantages to this product.

Long term surgical and hearing outcomes in the management of tympanomastoid paragangliomas

OBJECTIVE

To analyze the long term outcomes after surgery in tympanomastoid paragangliomas.

STUDY DESIGN

Retrospective study.

METHODS

The charts of 145 patients with tympanomastoid paragangliomas managed between 1988 and 2013 were reviewed. The clinical features, audiological data, pre- and postoperative notes were noted. The tumors were staged according to the modified Fish and Mattox classification. The surgical approaches for all patients were formulated according to the surgical algorithm developed at our center.

RESULTS

34 (23.5%), 46 (31.7%), 22 (15.2%), 18 (12.4%) and 25 (17.2%) patients were diagnosed to have TMP class A1, A2, B1, B2 and B3 tumors respectively. Gross tumor resection was achieved in 141 (97.2%) patients. The facial nerve was uncovered in four patients and infiltrated in three. The cochlea was found eroded in seven cases. The mean follow-up was 48.4 months. Recurrence was seen in one patient (0.7%). In the cases where the facial nerve was preserved (n=143), the nerve function was graded as HB grade 1 in 138 patients (97%). Postoperatively, the mean AC showed an improvement in all categories except in class B2 and B3, which corresponds to the classes that include patients who underwent subtotal petrosectomy.

CONCLUSION

We report the long term surgical outcomes in tympanomastoid paragangliomas in the largest series published till date. It is possible to completely eradicate all types of tympanomastoid paragangliomas with minimum sequelae by choosing the correct surgical approach to achieve adequate exposure for individual tumor classes as described in our classification and algorithm.

LEVEL OF EVIDENCE

IIb.

Impact of cholesterol lowering treatment on plasma kynurenine and tryptophan concentrations in chronic kidney disease: relationship with oxidative stress improvement

BACKGROUND AND AIM

Tryptophan (Trp) degradation via indoleamine (2,3)-dioxygenase (IDO), with consequent increased in kynurenine (Kyn) concentrations, has been proposed as marker of immune system activation. Oxidative stress (OS) might contribute to the pro-inflammatory state in chronic kidney disease (CKD) through the activation of NF-kB, with consequent activation and recruitment of immune cells.

METHODS AND RESULTS

Serum concentrations of Trp and Kyn, oxidative stress indices malondialdehyde (MDA) and allantoin/uric acid (All/UA) ratio and anti-oxidant amino acid taurine were measured in 30 CKD patients randomized to 40 mg/day simvastatin (group 1), ezetimibe/simvastatin 10/20 mg/day (group 2) or ezetimibe/simvastatin 10/40 mg/day (group 3) and treated for 12 months. Baseline Kyn and Kyn/Trp ratio were higher in CKD patients vs. healthy controls (1.67 ± 0.62 μmol/L vs 1.25 ± 0.40 μmol/L, p < 0.01 and 0.036 ± 0.016 vs 0.023 ± 0.010, p < 0.001 respectively). Both Kyn and Kyn/Trp ratio significantly decreased after cholesterol lowering treatment, to values comparable with healthy controls after one year treatment (1.67 ± 0.62 μmol/L vs 1.31 ± 0.51 μmol/L, p < 0.0001 and 0.036 ± 0.016 vs 0.028 ± 0.012 p < 0.0001, respectively). This was paralleled by a significant decrease in MDA (218 ± 143 nmol/L vs 176 ± 123 nmol/L, p < 0.01) and All/UA ratio (1.47 ± 0.72 vs 1.19 ± 0.51, p < 0.01) in CKD patients.

CONCLUSIONS

Amelioration of both oxidative and inflammation status after cholesterol lowering treatment in CKD might be mediated by restoration of antioxidant taurine concentrations during therapy (from 51.1 ± 13.3 μmol/L at baseline to 63.1 ± 16.4 μmol/L, p < 0.001 by ANOVA), suggesting that improvement of both oxidative and inflammation status in CKD patients could be explained, at least partly, by the cholesterol lowering effects.

Regular cigarette smoking influences the transsulfuration pathway, endothelial function, and inflammation biomarkers in a sex-gender specific manner in healthy young humans

Cigarette smoking (CS) is the primary cause of preventable morbidity and mortality. Abundant clinical evidence suggests that CS is more harmful to women; however, the mechanisms responsible for these differences are not yet known. CS alters endothelial function, the redox state, inflammation, and global DNA methylation, which is associated with one-carbon metabolism and the transsulfuration pathway. However, it is not known whether the previously identified alterations are sex-gender related. Healthy adult men and oral contraceptive-free women with regular menstrual cycles were enrolled; women were examined during the follicular phase. Men had higher plasma levels of uric acid, total bilirubin, homocysteine, glutamylcysteine, total glutathione, cysteinylglycine; had more monocytes and released more TNF-alpha from human monocytes derived macrophages (hMDMs), but they had fewer platelets and lower levels of DNA methylation, and their hMDMs released less TNF-alpha after LPS stimulation. MDA, taurine, cysteine, arginine, ADMA, and SDMA were not different. CS decreased global DNA methylation more in women and increased the platelet, monocyte, and lymphocyte counts and the homocysteine, arginine, and ADMA levels only in women, whereas increased the neutrophil and eosinophil counts only in men. Additionally, CS reduced the sex-gender differences in total bilirubin, basal and LPS-induced TNF-alpha release, total glutathione, and glutamylcysteine, leaving unchanged cysteinylglycine, taurine, SDMA, MDA, and cysteine. These data suggest that cardiovascular risk factors seem to come earlier in young healthy female smokers than in young healthy male smokers, supporting the greater alarmism regarding the effects of CS in women and providing a basis for understanding the sex-gender differences. These results also suggest that cessation programs targeting women are needed.

Oral contraceptives modify DNA methylation and monocyte-derived macrophage function

Background

Fertile women may be encouraged to use contraception during clinical trials to avoid potential drug effects on fetuses. However, hormonal contraception interferes with pharmacokinetics and pharmacodynamics and modifies internal milieus. Macrophages depend on the milieu to which they are exposed. Therefore, we assessed whether macrophage function would be affected by the use of combined oral contraceptives (OCs) and if this influence depended on the androgenic or non-androgenic properties of progestin.

Methods

Healthy adult women were enrolled and stratified into two groups: women who did not use OCs (Fs) and women treated with OCs (FOCs). FOCs were further stratified as a function of androgenic (FOCA⁺) and non-androgenic (FOCA^-) properties of progestins. Routine hematological, biochemical, inflammatory and endothelial dysfunction parameters were measured. Monocyte-derived macrophages (MDMs) were evaluated for the expression and activity of estrogen receptors and androgen receptors, and release of tumor necrosis factor α (TNFα) was measured from unstimulated and lipopolysaccharide-stimulated cells.

Results

As is already known, the use of OCs changed numerous parameters: the number of lymphocytes, iron levels, total iron-binding capacity of transferrin, triglycerides, high-density lipoprotein, total cholesterol, and C-reactive protein increased, while prothrombin time and alkaline phosphatase decreased. Hormonal levels also varied: cortisol was higher in FOCs, while luteinizing hormone, follicle-stimulating hormone, and testosterone were lower in FOCs. Asymmetric dimethylarginine, an index of endothelial function, was lower in FOC than in Fs, as were cysteine and bilirubin. The androgenic properties of progestins affected the activity of OCs: in particular, white blood cell count, hemoglobin, high-density lipoprotein and calcium were higher in FOCA^- than in FOCA⁺, whereas percentage oxygen saturation and γ-glutamyl transpeptidase were lower in FOCA^- than in FOCA⁺. Importantly, FOCs had a lower global DNA methylation, indicating that OC may have epigenetic effects on gene expression. OC did not modify the expression of androgen receptor but increased estrogen receptor α expression, more considerably in FOCA⁺, and decreased estrogen receptor β, more considerably in FOCA^-. Importantly, the activation state of estrogen receptor β in FOCs was decreased, while estrogen receptor α was not active in either Fs or FOCs. Unstimulated MDMs obtained from FOCs showed higher release of TNFα in comparison with Fs. After lipopolysaccharide stimulation, the release of TNFα was significantly higher in Fs than in FOCs.

Conclusions

OC use induced many changes in hematological and plasmatic markers, modifying hormonal levels, endothelial function, inflammation index and some redox state parameters, producing a perturbation of the internal milieu that impacted macrophagic function. In fact, different levels of estrogen receptor expression and release of TNFα were observed in macrophages derived from OC users. Some of the above activities were linked to the androgenic properties of progestin. Even though it is not known whether these effects are reversible, the results indicate that to avoid potential skewing of results only a single type of OC should be used during a single clinical trial.

Petrous bone cholesteatoma

Petrous bone cholesteatoma is a rare pathologic entity and may be a difficult surgical challenge because of potential involvement of the facial nerve, carotid artery, dura mater, otic capsule, and risk of cerebrospinal fluid leak. The objective of this article is to present a personal classification of petrous bone cholesteatomas, a survey of recent surgical attitudes, and our present surgical strategy based on our experience with 54 operations between 1978 and 1990. Radical petromastoid exenteration with marsupialization and the middle cranial fossa approach were used only for small pure infra- or supralabyrinthine cholesteatomas, respectively. The enlarged transcochlear approach with closure of the external auditory canal was used for infralabyrinthine, infralabyrinthine-apical, and massive petrous bone cholesteatomas. Five cases with petrous bone cholesteatomas in different locations are described in detail to present the signs and symptoms together with the management.

An easy, cost-effective and time-conserving method of studying the vascular anatomy of the base of the skull

In this work we present a simple, rapid, cost-effective and time-conserving method of studying the vascular anatomy of the base of the skull. This method is based on the injection of the arteries and veins with an appropriate coloring solution that possesses the property of rapid solidification. This technique of preparation of the coloring solution and the method of injection is described in detail. The advantages and disadvantages of this technique are also discussed.

The system of the modified transcochlear approaches to the petroclival area and the prepontine cistern

Between June 1986 and June 1993 46 different tumors (27 extradural and 19 intradural) located in the petroclival area and/or prepontine cistern have been operated on at The Gruppo Otologico Piacenza and the ENT Department of Bergamo, Italy using a modification of the transcochlear approach. Total tumor removal was obtained in all cases. Complications occurred in eight patients. One patient died due to infarction of the brain stem. The system of modified transcochlear approaches conceived for the removal of various intradural and extradural tumors is presented. This approach, together with its modifications, is the major operative access to the central skull base and clivus among a series of lateral approaches described in the literature. The basilar surgical technique (type A) and its modifications (types B, C, D) are described in detail, and five different, illustrative cases are presented. Indications, limits, results, and complications related to the approach are discussed.

Intratemporal hemangiomas involving the facial nerve: diagnosis and management

Intratemporal vascular tumors involving the facial nerve are rare benign lesions. Because of their variable clinical features, they are often misdiagnosed preoperatively. This study presents a series of 21 patients with such lesions managed from 1977 to 1994. Facial nerve dysfunction was the most common complaint, present in 60% of the cases, followed by hearing loss, present in 40% of cases. High-resolution computed tomography, magnetic resonance imaging with gadolinium, and a high index of clinical suspicion is required for preoperative diagnosis of these lesions. Early surgical resection of these tumors permits acceptable return of facial nerve function in many patients.

Surgical anatomy of the extended middle cranial fossa approach

The extended middle cranial fossa approach includes removal of the petrous bone from its subtemporal surface in order to expose widely the internal auditory canal and the posterior fossa dura around its porus while preserving all the important and closely related anatomical structures. We have dissected 25 temporal bones and five fresh cadavers in order to define the limits of this approach. Measurements were obtained between the different structures to find reliable angles and distances that could guide working in this area. A new method of identification of the internal auditory canal is discussed based on the measurements taken.The results of the present work showed wide variations in the different structures. The arcuate eminence was coincident with the superior semicircular canal in only 48% of bones. Dehiscence of the geniculate ganglion and of the internal carotid artery was noted in 16% and 20% of specimens, respectively. The angles measured between the different structures showed great variations. However, the angle between the internal auditory canal and superior petrosal sinus was constant. Though the extended middle cranial fossa is a versatile approach, it affords a limited access to the cerebellopontine angle. A thorough understanding of the complex and variable anatomy of this area is necessary should this approach be utilized.

Posterior fossa meningioma: surgical strategy

Posterior fossa meningioma is the second most common tumor in the cerebellopontine angle. It has a higher rate of postoperative morbidity and mortality compared to acoustic neuroma. Forty posterior fossa meningioma patients managed in our centers were reviewed. Thirty-nine patients were managed surgically with 42 surgical procedures. The approaches used were the translabyrinthine approach in 18 patients (43%), the modified transcochlear in 11 cases (26%), the petro-occipital transsigmoid in 5 cases (12%), the suboccipital in 4 cases (10%), the petro-occipital trassigmoid transcervical in 2 cases (5%), the petro-occipital transsigmoid transtentorial in 1 case (2%), and a subtemporal transtentorial for another case (2%). Facial nerve anatomical integrity was preserved in 87% of procedures but was interrupted in 5 cases, with 4 of the latter subsequently repaired. Total tumor removal was accomplished in 38 cases. A second-stage total tumor removal is planned for the remaining case. There was only one case of perioperative death and no cases of radiological recurrence so far.

Meningiomas intrinsic to the geniculate ganglion

Geniculate ganglion meningiomas are extremely rare lesions-only 14 cases have been reported in the literature. Two new cases of these tumors are described. On computed tomography and magnetic resonance imaging, both lesions appeared centered on the area of the geniculate ganglion, extending to the tympanic cleft and eroding the middle cranial fossa floor. The first case was treated through a middle cranial fossa approach. Because the tumor was so large in the second case, a subtotal petrosectomy was used. The authors review the literature to clarify the clinical and radiological characteristics of these tumors and their surgical treatment.

Decision making in acoustic neuroma management: the only hearing ear

Patients with acoustic neuroma in their only hearing ear are not frequently seen in clinical practice. Managing this group of patients is a challenge to both patient and surgeon. In this study we report on five cases of acoustic neuroma in an only hearing ear. Our decision for nonsurgical management of those patients with regular follow-up using auditory brainstem responses and magnetic resonance imaging is discussed. Other management options currently available are considered as well.

Fast-growing vestibular schwannoma

A case of a Jehovah's witness affected by an intracanalicular vestibular schwannoma with an extremely fast growth rate is presented. Nine months after presentation, the tumor reached 23 mm in the cerebellopontine angle. A partial removal through a retrosigmoid approach was planned. Because of the presence of a dominant high jugular bulb masquering the internal auditory canal, the intracanalicular portion of the tumor was left in place. The residual tumor grew 12 mm in 2 months. Even after a gross total removal through a middle cranial fossa approach, the tumor recurred, reaching the size of 30 mm in 17 months. A modified transcochlear approach was then performed, and the patient was free of disease at the last radiologic follow-up, 8 months after the surgery. We illustrate our strategy in treating this aggressive benign lesion with unusual behavior.

A posterolateral approach to the skull base: the petro-occipital transsigmoid approach

This posterolateral approach is directed to the petro-occipital skull base and is a combination of a suboccipital craniotomy, with an inferoposterior petrosectomy. The areas exposed are the jugular foramen, occipital condyle, lower clivus to the midline, petrous apex, tympanic cavity, the vertical portion of the intrapetrous carotid artery below the level of the eustachian tube, cerebellopontine angle, the jugulocarotid space in the upper neck. We evaluated 45 cases as follows: 13 chemodectomas, 14 lower cranial nerve schwannomas, 10 meningiomas, and 8 other lesions. The approach is indicated for extra-, intra-, and transdural lesions of the jugular foramen area. The transdural lesions could be extirpated in a single procedure without cerebrospinal fluid leak. This, in addition to preservation of the facial nerve, middle and inner ear functions, constituted the main advantages of this approach. Lower cranial nerve deficit formed the major morbidity in the present series and is still an unsolved problem in such cases.

Intermediate nerve schwannoma: a rare tumour

The intermediate nerve (IN), also called the nerve of Wrisberg, is a relatively small nerve with a variable anatomical course. Currently, this nerve is not addressed well in the pertinent literature. Pre-operative diagnosis of IN tumours is clinically challenging due to the lack of related symptoms. Symptoms are typically caused by the functional deterioration of neighbouring anatomical structures. In this report, we describe a patient with a schwannoma that arose at the porus acusticus of the internal auditory canal; during surgery, this proved to originate from the IN. We discuss our findings in the context of previously reported cases of IN schwannomas and analyse the vague characteristics and symptoms of this rare tumour.

Ultra-fast adenosine 5'-triphosphate, adenosine 5'-diphosphate and adenosine 5'-monophosphate detection by pressure-assisted capillary electrophoresis UV detection

Herein, we report a new CE method to measure adenine nucleotides adenosine 5'-triphosphate, adenosine 5'-diphosphate, and adenosine 5'-monophosphate in red blood cells. For this purpose, 20 mmol/L sodium acetate buffer at pH 3.80 was used as running electrolyte, and the separation was performed by the simultaneous application of a CE voltage of 25 kV and an overimposed pressure of 0.2 psi from inlet to outlet. A rapid separation of these analytes in less than 1.5 min was obtained with a good reproducibility for intra- and inter-assay (CV<4 and 8%, respectively) and an excellent analytical recovery (from 98.3 to 99%). The applicability of our method was proved by measuring adenine nucleotides in red blood cells.

Quantification of neurotransmitter amino acids by capillary electrophoresis laser-induced fluorescence detection in biological fluids

The role of neurotransmitter amino acids (NAAs) in the functioning of the nervous system has been the focus of increasingly intense research over the past several years. Among the various amino acids that have important roles as neurotransmitters, there are alanine (Ala), glutamic acid (Glu), aspartic acid (Asp), serine (Ser), taurine (Tau) and glycine (Gly). NAAs are present in plasma, cells and--at trace levels--in all biological fluids, but complex components in biological matrices make it difficult to determine them in biological samples. We describe a new capillary electrophoresis (CE) method with laser-induced fluorescence detection by which analytes are resolved in less than 12 minutes in a 18 mmol/L phosphate run buffer at pH 11.6. The use of elevated temperatures during sample derivatization leads to a drastic reduction in the reaction time, down to 20 min, compared to the 6-14 h usually described for reactions between FITC and amino acids at room temperature. In order to demonstrate its wide range of applications, the method was applied to the analysis of NAA in human plasma and in other sample types, such as red blood cells, urine, cultured cells, cerebrospinal fluid, saliva and vitreous humor, thus avoiding the typical limitations of other methods, which are normally suitable for use with only one or two matrix types.

Increased low-density lipoprotein S-homocysteinylation in chronic kidney disease

BACKGROUND

Since low-density lipoprotein (LDL) S-homocysteinylation has been recently reported to enhance atherogenicity of lipoprotein, we have investigated the levels of homocysteine (Hcy) linked to LDL in chronic proteinuric patients in which lipid abnormalities highly contribute to the excess of morbidity and mortality.

METHODS

We used capillary electrophoresis to measure LDL-bound thiol Hcy, cysteine (Cys), cysteinylglycine (Cys-Gly), glutathione (GSH), and glutamylcysteine (Glu-Cys) in 30 chronic kidney disease (CKD) individuals and 60 healthy volunteers.

RESULTS

We found more elevated levels of total plasma Hcy, Cys, GSH and Glu-Cys in patients than in controls and also found that Hcy and Cys bound to LDL were significantly increased in nephropathic subjects. By multiple linear regression, we found that in healthy people, total Hcy was the most important determinant of LDL-bound Hcy and Cys-Gly was negatively associated with apoB-Hcy concentrations. In CKD the most important determinant of homocysteinylation was creatinine while total plasma Hcy is weakly associated with apoB-Hcy.

CONCLUSIONS

The increased levels in Hcy-LDL observed in CKD patients might account, at least in part, for the excess of cardiovascular risk; thus LDL S-homocysteinylation can be considered a key marker of risk for cardiovascular disease in these individuals.

Determination of homocysteine thiolactone, reduced homocysteine, homocystine, homocysteine-cysteine mixed disulfide, cysteine and cystine in a reaction mixture by overimposed pressure/voltage capillary electrophoresis

An elevated level of thiol amino acid homocysteine is associated with several complex disorders. Homocysteine ability to bind proteins, thereby modulating their structure and function, is proposed to be one of the mechanisms of homocysteine induced pathogenecity. Homocysteine and homocysteine thiolactone bind to protein cysteine and lysine residues respectively. A major hurdle in studying protein homocysteinylation is the lack of suitable analytical techniques to determine simultaneously the concentrations of reduced and oxidized forms of homocysteine and cysteine (especially homocysteine-cysteine mixed disulfide) together with thiolactone formed during the reaction of homocysteine or thiolactone with proteins. Herein we report a capillary electrophoresis method to determine simultaneously the levels of these intermediates. For this 40 mmol/L Tris phosphate buffer at (pH 1.60) was used as running electrolyte, and the separation was performed by the simultaneous application of a CE voltage of 15kV and an overimposed pressure of 0.1 psi. A rapid separation of these intermediates in less than 6 min with a good reproducibility of both peak areas (CV<2%) and migration time (CV<0.2%) was obtained. The applicability of our method was validated by incubating reduced homocysteine and albumin and measuring the reaction intermediates in the solution mixture.

[Emotional aspects and quality of life of patients after acoustic neuroma surgery]

Acoustic neuromas are rare lesions arising in the internal auditory canal (IAC) and extending in the posterior cranial fossa. Surgical removal is the treatment of choice; peri and postoperative complications are directly related to the size of the tumour. Some Authors think the surgical treatment and related temporary or permanent neurological deficits could change the QoL and the psychological status.

PURPOSE

The aim of this analysis is to ascertain if the surgical procedure could significantly worsen the QoL of this population 12 months after the discharge from surgical department.

METHODS

By using a questionnaires of Quality of Life aims to evaluate the impact that the disease and the surgical procedure have on this population.

SUBJECTS

We have evaluated a sample of 150 subjects one year after the surgical removal of a acoustic neuroma. Data have been collected through questionnaires the Whoqol-Brief, the BDI, the STAI Y1 and Y2 and specific item to assess effects of postoperative dysfunctions.

RESULTS

Data reveal a negative effect on QoL, 94% of the subjects show lower score at Whoquol-Brief and in anxiety with scores higher than normative score sample (state-anxiety (t = 5.602 p = .000; trait-anxiety: t = 4.354 p = .000). Higher incidence of depressive disorders have not been found.

CONCLUSION

Psychological support to subjects after discharge from acoustic neuroma surgical removal should be tailored to improve quality of life and for a better management of anxiety.

Sourdough-leavened bread improves postprandial glucose and insulin plasma levels in subjects with impaired glucose tolerance

Sourdough bread has been reported to improve glucose metabolism in healthy subjects. In this study postprandial glycaemic and insulinaemic responses were evaluated in subjects with impaired glucose tolerance (IGT) who had a meal containing sourdough bread leavened with lactobacilli, in comparison to a reference meal containing bread leavened with baker yeast. Sixteen IGT subjects (age range 52-75, average BMI 29.9 +/- 4.2 kg/ m2) were randomly given a meal containing sourdough bread (A) and a meal containing the reference bread (B) in two separate occasions at the beginning of the study and after 7 days. Sourdough bread was leavened for 8 h using a starter containing autochthonous Saccharomyces cerevisiae and several bacilli able to produce a significant amount of D-and L-lactic acid, whereas the reference bread was leavened for 2 h with commercial baker yeast containing Saccharomyces cerevisiae. Plasma glucose and insulin levels were measured at time 0, 30, 60, 120, and 180 min. In IGT subjects sourdough bread induced a significantly lower plasma glucose response at 30 minutes (p = 0.048) and a smaller incremental area under curve (AUC) delta 0-30 and delta 0-60 min (p = 0.020 and 0.018 respectively) in comparison to the bread leavened with baker yeast. Plasma insulin response to this type of bread showed lower values at 30 min (p = 0.045) and a smaller AUC delta 0-30 min (p = 0.018). This study shows that in subjects with IGT glycaemic and insulinaemic responses after the consumption of sourdough bread are lower than after the bread leavened with baker yeast. This effect is likely due to the lactic acid produced during dough leavening as well as the reduced availability of simple carbohydrates. Thus, sour-dough bread may potentially be of benefit in subjects with impaired glucose metabolism.

Technique to prevent post-operative CSF leak in the translabyrinthine excision of vestibular schwannoma

Cerebrospinal fluid (CSF) leak following VS removal is a challenging complication. With experience, it can be seen that anatomical factors such as the extent of pneumatization of the petrous temporal bone and posterior wall of the internal auditory canal play animportant role in contributing to CSF leak. Nevertheless, the risk of post-operative CSF leak remains a major concern for both the surgeon and patient. This paper describes a technique, which we have used since 1994, and which has helped us to achieve the lowest reported rate of post-operative CSF leak in translabyrinthine excision of vestibular schwannoma in the world literature.

Molecular characterization of lactic acid bacteria from sourdough breads produced in Sardinia (Italy) and multivariate statistical analyses of results

The objective of this work was to investigate the structure and diversity of lactic acid bacteria (LAB) communities in sourdough used for the production of traditional breads (Carasau, Moddizzosu, Spianata, Zichi) in Sardinia. 16S rDNA sequencing and Randomly Amplified Polymorphic DNA (RAPD-PCR) was applied for the identification and typing of the LAB isolated from 25 samples of sourdoughs. Multivariate statistical techniques were applied to RAPD-PCR pattern to study the biological diversity of sourdough samples. Twelve different species of LAB were identified, and most isolates were classified as facultative heterofermentative lactobacilli. Lactobacillus pentosus dominated the lactic microflora of many samples while Lactobacillus sanfranciscensis was isolated only from a limited number of samples. Although heterofermentative species represented between between 30% and 60% of the isolates in Carasau, Spianata and Zichi sourdoughs, only 2% of the isolates from Moddizzosu sourdoughs were identified as heterofermentative LAB. RAPD-PCR with a single primer followed by cluster analysis did not allow the identification of the isolates at the species level. However, a multidimensional scaling/bootstrapping approach on the RAPD-PCR patterns uncovered the diversity of the LAB communities of LAB showing differences both within and between bread types.