Deletion of calcineurin from GFAP-expressing astrocytes impairs excitability of cerebellar and hippocampal neurons through astroglial Na+/K+ ATPase

Astrocytes perform important housekeeping functions in the nervous system including maintenance of adequate neuronal excitability, although the regulatory mechanisms are currently poorly understood. The astrocytic Ca²⁺/calmodulin-activated phosphatase calcineurin (CaN) is implicated in the development of reactive gliosis and neuroinflammation, but its roles, including the control of neuronal excitability, in healthy brain is unknown. We have generated a mouse line with conditional knockout (KO) of CaN B1 (CaNB1) in glial fibrillary acidic protein-expressing astrocytes (a stroglial c alcin eurin KO [ACN-KO]). Here, we report that postnatal and astrocyte-specific ablation of CaNB1 did not alter normal growth and development as well as adult neurogenesis. Yet, we found that specific deletion of astrocytic CaN selectively impairs intrinsic neuronal excitability in hippocampal CA1 pyramidal neurons and cerebellar granule cells (CGCs). This impairment was associated with a decrease in after hyperpolarization in CGC, while passive properties were unchanged, suggesting impairment of K⁺ homeostasis. Indeed, blockade of Na⁺/K⁺-ATPase (NKA) with ouabain phenocopied the electrophysiological alterations observed in ACN-KO CGCs. In addition, NKA activity was significantly lower in cerebellar and hippocampal lysates and in pure astrocytic cultures from ACN-KO mice. While no changes were found in protein levels, NKA activity was inhibited by the specific CaN inhibitor FK506 in both cerebellar lysates and primary astroglia from control mice, suggesting that CaN directly modulates NKA activity and in this manner controls neuronal excitability. In summary, our data provide formal evidence for the notion that astroglia is fundamental for controlling basic neuronal functions and place CaN center-stage as an astrocytic Ca²⁺-sensitive switch.     

The diagnostic usefulness of the combined COMPASS 31 questionnaire and electrochemical skin conductance for diabetic cardiovascular autonomic neuropathy and diabetic polyneuropathy

The study investigated the diagnostic performance for diabetic cardiovascular autonomic neuropathy (CAN) and diabetic polyneuropathy (DPN) of the combined use of composite autonomic symptom score (COMPASS) 31, validated questionnaire for autonomic symptoms of CAN, and electrochemical skin conductance (ESC), proposed for detecting DPN and CAN. One‐hundred and two participants with diabetes (age 57 ± 14 years, duration 17 ± 13 years) completed the COMPASS 31 before assessing cardiovascular reflex tests (CARTs), neuropathic symptoms, signs, vibratory perception threshold (VPT), thermal thresholds (TT), and ESC using Sudoscan. Two patterns were evaluated: (a) the combined abnormalities in both tests (COMPASS 31+ESC), and (b) the abnormality in COMPASS 31 and/or ESC (COMPASS 31 and/or ESC). CAN (≥ 1 abnormal CART) and confirmed CAN (≥ 2 abnormal CARTs) were present in 28.1% and 12.5%, DPN (two abnormalities among symptoms, signs, VPT, and TT) in 52%, abnormal COMPASS 31 (total weighted score >16.44) in 48% and abnormal ESC (hands ESC <50 μS and/or feet ESC <70 μS) in 47.4%. Both the patterns—COMPASS 31+ESC and COMPASS 31 and/or ESC—were associated with CAN and DPN (P < .01). COMPASS 31 and ESC reached a sensitivity of 75% and 83% for confirmed CAN, and a specificity of 65% and 67% for DPN. When combining the tests, the sensitivity for CAN rose by up to 100% for CAN and the specificity up to 89% for DPN. The combination of the tests can allow a stepwise screening strategy for CAN, by suggesting CAN absence with combined normality, and prompting to CARTs with combined abnormality.     

Erosive hand osteoarthritis and systemic sclerosis: A casual association?

To describe an unexpected association between a patient affected with erosive hand osteoarthritis (EHOA) and systemic sclerosis (SSc). We report a case of SSc presenting typical radiological findings of EHOA in a 60-year-old woman referred to our outpatient Rheumatology Unit. Physical examination revealed puffy hands with sclerodactyly and concomitant adduction of the thumb and subluxation of the first carpometacarpal (CMC) and metacarpophalangeal (MCP) joints bilaterally and nodose deformities of the distal interphalangeal (DIP). Hand X-rays showed joint space narrowing, osteophytosis and bone sclerosis of the proximal interphalangeal (PIP) joints. The DIP joints showed central bone erosion, collapse of the subchondral bone plate and typical “gull-wing” type deformity. EHOA is a particularly aggressive subset of osteoarthritis (OA). In light of its still unclear pathogenesis, peculiarities in the disease characteristics may be useful to better define the EHOA patient profile. One of these is an unexpected association with some autoimmune diseases. EHOA and SSc in the same patient is not uncommon, and it could speculate that there may be a genetic and autoimmune involvement.     

Identification of New Natural CphA Metallo-β-Lactamases CphA4 and CphA5 in Aeromonas veronii and Aeromonas hydrophila Isolates from Municipal Sewage in Central Italy

Two new natural CphA metallo-β-lactamases, the CphA4 and CphA5 enzymes, were identified in water samples from municipal sewage in central Italy. Compared to CphA, the CphA4 and CphA5 enzymes showed numerous point mutations. These enzymes have a narrow spectrum of substrates focused on carbapenems only. CphA5 showed k_cat values about 40-, 12-, and 97-fold higher than those observed for CphA4 versus imipenem, ertapenem, and biapenem, respectively.     

P-glycoprotein, lung resistance-related protein and multidrug resistance-associated protein in de novo adult acute lymphoblastic leukaemia

P-glycoprotein (P-gp), lung resistance-related protein (LRP) and multidrug resistance-associated protein (MRP) expression, and blast cell intracellular daunorubicin accumulation (IDA) were evaluated in 95 previously untreated cases of adult acute lymphoblastic leukaemia (ALL) using flow cytometry. Forty-five out of 95 (47%) patients were P-gp positive (+), 12/66 (18%) were LRP+ and 11/66 (17%) were MRP+. Eighteen out of 66 (28%) patients showed a simultaneous multidrug resistance (MDR)-related protein expression higher than controls for more than one protein, while 24/66 (36%) cases did not overexpress any protein. Twenty-one out of 24 (87%) cases overexpressing at least one MDR-related protein had a defect in accumulating daunorubicin into their blast cells, while only 4/24 (16%) cases who did not overexpress any protein had similar features. The complete remission rates were similar in MDR-positive and -negative (-) patients but relapses within 6 months were more frequent in P-gp+ cases, and therefore the disease-free survival duration was shorter in P-gp+ than in P-gp- patients (P = 0.01). The number of MRP+ and/or LRP+ cases was too small to be able to draw any conclusion on their role in affecting or predicting therapy outcome. In conclusion, P-gp overexpression associated with a defect in daunorubicin accumulation is a frequent feature in adult ALL at onset and seems to be related to poorer therapy outcome and, consequently, a shorter disease-free survival. LRP and MRP overexpression seems to be a rare event and no conclusion can be drawn on its prognostic role.     

Regression of left ventricular hypertrophy and prevention of stroke in hypertensive subjects

BACKGROUND: Left ventricular hypertrophy (LVH) is a risk marker for stroke and its regression confers protection from stroke. The relationship between serial LVH changes and risk of stroke has never been investigated in a mixed population of hypertensive subjects with and without LVH. METHODS: In this study, 880 initially untreated hypertensive subjects (mean age 48 years, office blood pressure (BP) 155/98 mm Hg; 24-h BP 137/87 mm Hg) underwent tests including echocardiography and 24-h ambulatory BP monitoring at entry and after a median of 3.5 years, still in the absence of cardiovascular events. RESULTS: Months or years after the follow-up study, 34 of these subjects developed a first cerebrovascular event (stroke in 21, transient ischemic attack in 13). Event rate (x 100 patients per year) was 0.25 among the subjects who never developed echocardiographic LVH or with regression of LVH, versus 1.16 among the subjects with lack of regression or new development of LVH (log-rank test: P = .00001). Serial electrocardiogram (ECG) changes failed to define groups at different risk. In a Cox analysis, the risk of cerebrovascular events was 2.8 times higher (95% CI: 1.18-6.69) in the subset with lack of regression or new development of LVH than in that with LVH regression or persistently normal LV mass. Such effect was independent of age (P = .001) and 24-h systolic BP (P = .003). CONCLUSIONS: In a mixed hypertensive population with and without LVH at entry, serial changes in the echocardiographic indexes of LVH predict subsequent cerebrovascular events independently of office and ambulatory BP and other individual risk factors.     

Morphometric analysis of dental arch form changes in class II patients treated with clear aligners

Journal of Orofacial Orthopedics / Fortschritte der Kieferorthopädie - The purpose of this study was to evaluate the arch form changes in class&nbsp;II Caucasian patients treated with...     

Molecular and Serological Diversity of Neisseria meningitidis Carrier Strains Isolated from Italian Students Aged 14 to 22 Years

Neisseria meningitidis is an obligate human commensal that commonly colonizes the oropharyngeal mucosa. Carriage is age dependent and very common in young adults. The relationships between carriage and invasive disease are not completely understood. In this work, we performed a longitudinal carrier study in adolescents and young adults (173 subjects). Overall, 32 subjects (18.5%) had results that were positive for meningococcal carriage in at least one visit (average monthly carriage rate, 12.1%). Only five subjects tested positive at all four visits. All meningococcal isolates were characterized by molecular and serological techniques. Multilocus sequence typing, PorA typing, and sequencing of the 4CMenB vaccine antigens were used to assess strain diversity. The majority of positive subjects were colonized by capsule null (34.4%) and capsular group B strains (28.1%), accounting for 23.5% and 29.4% of the total number of isolates, respectively. The fHbp and nhba genes were present in all isolates, while the nadA gene was present in 5% of the isolates. The genetic variability of the 4CMenB vaccine antigens in this collection was relatively high compared with that of other disease-causing strain panels. Indications about the persistence of the carriage state were limited to the time span of the study. All strains isolated from the same subject were identical or cumulated minor changes over time. The expression levels and antigenicities of the 4CMenB vaccine antigens in each strain were analyzed by the meningococcal antigen typing system (MATS), which revealed that expression can change over time in the same individual. Future analysis of antigen variability and expression in carrier strains after the introduction of the MenB vaccine will allow for a definition of its impact on nasopharyngeal/oropharyngeal carriage.     

Lamivudine prophylaxis prevents hepatitis B virus reactivation in anti-HBc positive patients under rituximab for non-Hodgkin lymphoma

Backgound

A significant proportion of hepatitis B surface antigen (HBsAg) negative/anti-hepatitis B core antigen (anti-HBc) positive patients with non-Hodgkin lymphoma (NHL) undergoing rituximab-based chemotherapy (R-CT) may suffer hepatitis B virus (HBV) reactivation.