La presbiacusia. problematiche, diagnosi e opzioni riabilitative Presbycusis. problems, diagnosis and treatment

Presbycusis is sensorineural bilateral symmetrical, progressive hearing loss, caused by the advance of age. It involves mainly the higher frequencies and associated with tinnitus. Presbycusis the most frequent form of sensorineural hearing loss of the adult, characterized by the progressive difficulty following the conversation, especially in noisy environments. It is caused by reduction in the number of Corti cells, induced by genetic and environmental factors. In the elderly communication disorders generate isolation and depression, thereby causing a significant reduction of life quality. An observational study at our hospital in 2010, using questionnaires on verbal-acoustic communication (Self Assessment of Communication), found that older people have a poor perception of disability related to hearing loss. For presbycusis to be diagnosed, tone audiometry and speech and sovraliminary tests have to be carried out and must be integrated with the evaluation of extremely high frequencies (EHFs). In the majority of cases, rehabilitation involves conventional hearing aids. The most commonly used are retroauricular hearing aids, when these are contraindicated partially or totally implantable hearing device scan be used. Careful follow up of the patient is also fundamental, using benefit questionnaires to find the optimal fitting and therefore the best result

Does the addition of a second daily session of hyperbaric oxygen therapy to intratympanic steroid influence the outcomes of sudden hearing loss? [L’aggiunta di una seconda sessione giornaliera di camera iperbarica al trattamento steroideo intratimpanico influenza i risultati terapeutici nella sordità improvvisa?]

The aim of this study is to investigate whether, in addition to intratympanic steroid therapy, additional hyperbaric oxygen therapy (HBOT) sessions per day (twice a day for 5 days) is more useful than one session per day for 10 days in patients affected by severe and profound idiopathic sudden sensorineural hearing loss (ISSNHL). A total of 55 patients affected by unilateral severe and profound ISSNHL were recruited. Two protocols were adopted. In the first, 27 patients (13 with profound and 14 with severe hearing loss) underwent one session of HBOT per day for 10 days, 6 days a week. An HBOT session comprised a period of 14 minutes air compression followed by 90 min at 2.4 atm absolute (ATA) followed by a decompression period of 15 min in oxygen. Patients breathed 100% oxygen through an appropriate mask checked for leaks. Patients were given 0.4 ml of 62.5 mg/ml of intratympanic prednisolone during the first three days of the protocol. In the second protocol, 28 patients (10 with profound and 18 with severe hearing loss) received 10 sessions of HBOT, twice a day for five days, 2.4 ATA 90 min 100% oxygen. The intratympanic injections of prednisolone were given between the two sessions of HBOT during the first three days of the protocol. Since there were no significant differences in hearing outcomes between the two protocols, the present study shows that the protocol of two sessions of HBOT per day is a valid treatment and equally effective as the one HBOT session per day, but with shorter treatment time

The Differential Diagnosis of Discrepant Thyroid Function Tests: Insistent Pitfalls and Updated Flow-Chart Based on a Long-Standing Experience.

Background: Discrepant thyroid function tests (TFTs) are typical of inappropriate secretion of TSH (IST), a rare entity encompassing TSH-secreting adenomas (TSHoma) and Resistance to Thyroid Hormone (RTHβ) due to THRB mutations. The differential diagnosis remains a clinical challenge in most of the cases. The objective of this study was to share our experience with patients presenting with discrepant TFTs outlining the main pitfalls in the differential diagnosis. Methods: medical records of 100 subjects with discrepant TFTs referred to Thyroid Endocrine Centers at the University of Milan were analyzed, retrospectively. Patients were studied by dynamic testing (TRH test, T3-suppression test, or a short course of long-acting somatostatin analog, when appropriate), THRB sequencing, and pituitary imaging. Results: 88 patients were correctly diagnosed as RTHβ with (n = 59; 16 men, 43 women) or without THRB variants (n = 6; 2 men, 4 female) or TSHoma (n = 23; 9 men, 14 women). We identified 14 representative subjects with an atypical presentation or who were misdiagnosed. Seven patients, with spurious hyperthyroxinemia due to assays interference were erroneously classified as RTHβ (n = 4) or TSHoma (n = 3). Three patients with genuine TSHomas were classified as laboratory artifact (n = 2) or RTHβ (n = 1). Two TSHomas presented atypically due to coexistent primary thyroid diseases. In one RTHβ a drug-induced thyroid dysfunction was primarily assumed. These patients experienced a mean diagnostic delay of 26 ± 14 months. Analysis of the investigations which can differentiate between TSHoma and RTHβ showed highest accuracy for the T3-suppression test (100% specificity with a cut-off of TSH <0.11 μUI/ml). Pituitary MRI was negative in 6/26 TSHomas, while 11/45 RTHβ patients had small pituitary lesions, leading to unnecessary surgery in one case. Conclusions: Diagnostic delay and inappropriate treatments still occur in too many cases with discrepant TFTs suggestive of central hyperthyroidism. The insistent pitfalls lead to a significant waste of resources. We propose a revised flow-chart for the differential diagnosis

Soybean lectin enhances biofilm formation by Bradyrhizobium japonicum in the absence of plants

Soybean lectin (SBL) purified fromsoybean seeds by affinity chromatography strongly bound to Bradyrhizobium japonicum USDA 110 cell surface. This lectin enhanced biofilm formation by B. japonicum in a concentration-dependent manner. Presence of galactose during biofilm formation had different effects in the presence or absence of SBL. Biofilms were completely inhibited in the presence of both SBL and galactose, while in the absence of SBL, galactose was less inhibitory. SBL was very stable, since its agglutinating activity of B. japonicum cells as well as of human group A+ erythrocytes was resistant to preincubation for one week at 60°C. Hence, we propose that plant remnants might constitute a source of this lectin, which might remain active in soil and thus favor B. japonicum biofilm formation in the interval between soybean crop seasons.Facultad de Ciencias ExactasInstituto de Biotecnologia y Biologia Molecula

Analysis of the role of the two flagella of Bradyrhizobium japonicum in competition for nodulation of soybean

Bradyrhizobium japonicum has two types of flagella. One has thin filaments consisting of the 33-kDa flagellins FliCI and FliCII (FliCI-II) and the other has thick filaments consisting of the 65-kDa flagellins FliC1, FliC2, FliC3, and FliC4 (FliC1-4). To investigate the roles of each flagellum in competition for nodulation, we obtained mutants deleted in fliCI-II and/or fliC1-4 in the genomic backgrounds of two derivatives from the reference strain USDA 110: the streptomycin-resistant derivative LP 3004 and its more motile derivative LP 3008. All mutations diminished swimming motility. When each mutant was co-inoculated with the parental strain on soybean plants cultivated in vermiculite either at field capacity or flooded, their competitiveness differed according to the flagellin altered. ΔfliCI-II mutants were more competitive, occupying 64-80% of the nodules, while ΔfliC1-4 mutants occupied 45-49% of the nodules. Occupation by the nonmotile double mutant decreased from 55% to 11% as the water content of the vermiculite increased from 85% to 95% field capacity to flooding. These results indicate that the influence of motility on competitiveness depended on the water status of the rooting substrate.Instituto de Biotecnologia y Biologia Molecula

Analysis of the role of the two flagella of Bradyrhizobium japonicum in competition for nodulation of soybean

Bradyrhizobium japonicum has two types of flagella. One has thin filaments consisting of the 33-kDa flagellins FliCI and FliCII (FliCI-II) and the other has thick filaments consisting of the 65-kDa flagellins FliC1, FliC2, FliC3, and FliC4 (FliC1-4). To investigate the roles of each flagellum in competition for nodulation, we obtained mutants deleted in fliCI-II and/or fliC1-4 in the genomic backgrounds of two derivatives from the reference strain USDA 110: the streptomycin-resistant derivative LP 3004 and its more motile derivative LP 3008. All mutations diminished swimming motility. When each mutant was co-inoculated with the parental strain on soybean plants cultivated in vermiculite either at field capacity or flooded, their competitiveness differed according to the flagellin altered. ΔfliCI-II mutants were more competitive, occupying 64-80% of the nodules, while ΔfliC1-4 mutants occupied 45-49% of the nodules. Occupation by the nonmotile double mutant decreased from 55% to 11% as the water content of the vermiculite increased from 85% to 95% field capacity to flooding. These results indicate that the influence of motility on competitiveness depended on the water status of the rooting substrate.Instituto de Biotecnologia y Biologia Molecula

Soybean lectin enhances biofilm formation by Bradyrhizobium japonicum in the absence of plants

Soybean lectin (SBL) purified fromsoybean seeds by affinity chromatography strongly bound to Bradyrhizobium japonicum USDA 110 cell surface. This lectin enhanced biofilm formation by B. japonicum in a concentration-dependent manner. Presence of galactose during biofilm formation had different effects in the presence or absence of SBL. Biofilms were completely inhibited in the presence of both SBL and galactose, while in the absence of SBL, galactose was less inhibitory. SBL was very stable, since its agglutinating activity of B. japonicum cells as well as of human group A+ erythrocytes was resistant to preincubation for one week at 60°C. Hence, we propose that plant remnants might constitute a source of this lectin, which might remain active in soil and thus favor B. japonicum biofilm formation in the interval between soybean crop seasons.Facultad de Ciencias ExactasInstituto de Biotecnologia y Biologia Molecula

Analysis of the role of the two flagella of Bradyrhizobium japonicum in competition for nodulation of soybean

Bradyrhizobium japonicum has two types of flagella. One has thin filaments consisting of the 33-kDa flagellins FliCI and FliCII (FliCI-II) and the other has thick filaments consisting of the 65-kDa flagellins FliC1, FliC2, FliC3, and FliC4 (FliC1-4). To investigate the roles of each flagellum in competition for nodulation, we obtained mutants deleted in fliCI-II and/or fliC1-4 in the genomic backgrounds of two derivatives from the reference strain USDA 110: the streptomycin-resistant derivative LP 3004 and its more motile derivative LP 3008. All mutations diminished swimming motility. When each mutant was co-inoculated with the parental strain on soybean plants cultivated in vermiculite either at field capacity or flooded, their competitiveness differed according to the flagellin altered. ΔfliCI-II mutants were more competitive, occupying 64-80% of the nodules, while ΔfliC1-4 mutants occupied 45-49% of the nodules. Occupation by the nonmotile double mutant decreased from 55% to 11% as the water content of the vermiculite increased from 85% to 95% field capacity to flooding. These results indicate that the influence of motility on competitiveness depended on the water status of the rooting substrate.Instituto de Biotecnologia y Biologia Molecula

Therapy with different dose regimens of rituximab in patients with active moderate-to-severe Graves' Orbitopathy

Background: Immunosuppressive therapy of Graves’ orbitopathy (GO) is indicated during the active phase of disease. Intravenous steroids (IVGC) are effective in about 70% of patients, although unresponsiveness or relapse are observed. In previous studies, rituximab (RTX) has been shown to be effective in inactivating moderate-to-severe GO when used early in the disease, but its optimal dosage has never been studied in randomized clinical trials. Aim of this study was to compare the efficacy and safety of different doses of RTX, based on a post-hoc analysis of two open label studies and one prospective trial randomized to IVGC. Methods: of 40 patients (35 women, 5 men), with active moderate-to-severe GO treated with RTX, 14 received a single dose of 100 mg (Group 1), 15 a single dose of 500 mg (Group 2) and 11 two 1000 mg doses, administered one week apart (Group 3). Thyroid function, TSH-receptor antibodies (TRAb) and peripheral CD19+ cells were measured. Primary endpoint was disease inactivation, measured as a decrease of the Clinical Activity Score (CAS) of at least two points. Secondary endpoints were improvement of proptosis, diplopia, quality of life and safety. Results: Baseline CAS decreased significantly in all groups (P<0.0001), independently of GO duration or whether patients had newly occurring or relapsing GO after IVGC. Proptosis did not significantly change. There was an inverse correlation between the Gorman score for diplopia and RTX dose (P<0.01). The appearance score of the GO-QoL improved in Group 1 (P=0.015), and the visual function score, in Group 2 (P=0.04). A reduction of serum TRAb was observed in Group 1 (P=0.002) and Group 2 (P<0.0002), but not in Group 3. CD19+ cell decreased in all groups (P<0.01), independently of the dose. Conclusions: We studied the optimal dosage of RTX in the treatment of active moderate-to-severe GO. In this analysis, we considered the efficacy of RTX in inactivating GO, in changing its natural course, its effect on disease severity and on the patients’ quality of life. Based on our clinical findings, and balancing the cost of therapy, a single 500 mg dose regimen is suggested in the majority of patients

Lack of Galactose or Galacturonic Acid in <i>Bradyrhizobium japonicum</i> USDA 110 Exopolysaccharide Leads to Different Symbiotic Responses in Soybean

Exopolysaccharide (EPS) and lipopolysaccharide (LPS) from Bradyrhizobium japonicum are important for infection and nodulation of soybean (Glycine max), although their roles are not completely understood. To better understand this, we constructed mutants in B. japonicum USDA 110 impaired in galactose or galacturonic acid incorporation into the EPS without affecting the LPS. The derivative LP 3010 had a deletion of lspL-ugdH and produced EPS without galacturonic acid whereas LP 3013, with an insertion in exoB, produced EPS without galactose. In addition, the strain LP 3017, with both mutations, had EPS devoid of both galactosides. The missing galactosides were not replaced by other sugars. The defects in EPS had different consequences. LP 3010 formed biofilms and nodulated but was defective in competitiveness for nodulation; and, inside nodules, the peribacteroid membranes tended to fuse, leading to the merging of symbiosomes. Meanwhile, LP 3013 and LP 3017 were unable to form biofilms and produced empty pseudonodules but exoB suppressor mutants were obtained when LP 3013 plant inoculation was supplemented with wild-type EPS. Similar phenotypes were observed with all these mutants in G. soja. Therefore, the lack of each galactoside in the EPS has a different functional effect on the B. japonicum-soybean symbiosis.Facultad de Ciencias ExactasInstituto de Biotecnologia y Biologia Molecula