The Influence of Medial Comminution in the Treatment Choice of Radial Head Fracture.

INTRODUCTION: The aim of our retrospective study was to investigate the role of the medial side involvement in the treatment choice of radial head fractures. MATERIALS AND METHODS: We searched the databases of our institutions for the surgical procedures diagnosed as "fracture of the radial head" and for the procedures related to "prosthesis of the radial head" and "osteosynthesis of the radial head" in the period from May 2014 to October 2017. The fractures were first classified according to the Mason classification . We then allocated the patients into three study groups according to the site of the fracture, either the medial or lateral side of the radial head : Group A, with an isolated lateral fracture of the radius head; Group B1, with a medial fracture of the radius head with two medial fragments; and Group B2, with a medial fracture of the radius head with multiple medial fragments. We performed a multivariate analysis to identify statistically significant correlation between the pre-operative classifications of Mason and our study, the type of surgical procedure, and the clinical outcome. RESULTS: Mayo Elbow Performance (MEP) scores determined at the final follow-up of the study (mean 16.6 months, range 12-26 months) was excellent in 17 patients (4 in Group A, 6 in Group B1 and 7 in Group B2), and good in 12 patients (3 in Group A, 7 in Group B1, and 2 in Group B2). One patient showed a poor result in MEP score probably because of an infection and implant removal. CONCLUSION: Regarding medial fractures of the radial head, our study showed satisfactory results with a radial head prosthesis for comminuted or multifragmentary radial head fractures. For surgeons with advanced elbow fracture expertise, osteosynthesis could be attempted in a fracture pattern that involved only two medial fragments.

The Influence of Medial Comminution in the Treatment Choice of Radial Head Fracture

@#Introduction: The aim of our retrospective study was to investigate the role of the medial side involvement in the treatment choice of radial head fractures. Materials and Methods: We searched the databases of our institutions for the surgical procedures diagnosed as "fracture of the radial head" and for the procedures related to "prosthesis of the radial head" and "osteosynthesis of the radial head" in the period from May 2014 to October 2017. The fractures were first classified according to the Mason classification . We then allocated the patients into three study groups according to the site of the fracture, either the medial or lateral side of the radial head : Group A, with an isolated lateral fracture of the radius head; Group B1, with a medial fracture of the radius head with two medial fragments; and Group B2, with a medial fracture of the radius head with multiple medial fragments. We performed a multivariate analysis to identify statistically significant correlation between the pre-operative classifications of Mason and our study, the type of surgical procedure, and the clinical outcome. Results: Mayo Elbow Performance (MEP) scores determined at the final follow-up of the study (mean 16.6 months, range 12-26 months) was excellent in 17 patients (4 in Group A, 6 in Group B1 and 7 in Group B2), and good in 12 patients (3 in Group A, 7 in Group B1, and 2 in Group B2). One patient showed a poor result in MEP score probably because of an infection and implant removal. Conclusion: Regarding medial fractures of the radial head, our study showed satisfactory results with a radial head prosthesis for comminuted or multifragmentary radial head fractures. For surgeons with advanced elbow fracture expertise, osteosynthesis could be attempted in a fracture pattern that involved only two medial fragments.

Viruses are frequently present as the infecting agent in acute exacerbations of chronic obstructive pulmonary disease in patients presenting to hospital.

BACKGROUND: Viral causes of acute exacerbations of chronic obstructive pulmonary disease (AECOPD) are well recognised but only recently have rapid tests become available. AIMS: To identify respiratory viruses in the general population and those associated with hospitalisation in AECOPD using polymerase chain reaction (PCR) on nasopharyngeal aspirate (NPA), and the relationship between symptoms, viral detection and inflammatory markers. METHODS: A review of viruses detected in the general population in a health district between August 2014 and July 2015, using multiplex PCR for viruses from NPA samples. In addition, a single hospital, retrospective audit of patients admitted with suspected AECOPD was conducted. RESULTS: Of the 8811 NPA tested, 5599 (64%) were positive for at least one virus and 2069 of these were obtained from adults. In adults, the most common viruses identified were Influenza A (31%), Rhinovirus (27%) and respiratory syncytial virus A/B (10%). Most patients with AECOPD (102 of 153) had NPA sent for viral PCR testing and 59 (58%) were positive. The most common viruses identified were Influenza A (31%), Rhinovirus (24%) and respiratory syncytial virus A/B (17%) with co-infecting bacteria cultured in 22 sputum samples. Patients with influenza-like symptoms were more likely to have a positive viral PCR than those without symptoms (P < 0.004). The median C-reactive protein on admission was lower in the virus-infected than uninfected AECOPD (28 vs 60 mg/L, P < 0.026). CONCLUSION: The spectrum of viruses detected in patients with AECOPD is similar to that of the general population. Viruses are more likely to be identified in patients with AECOPD who present with influenza-like symptoms and a low C-reactive protein.

Dihydropyridine-sensitive and -insensitive voltage-operated calcium channels participate in the control of glucose-induced insulin release from human pancreatic beta cells.

Calcium ion entry through voltage-operated calcium channels is a crucial step in the coupling of beta cell depolarization with insulin secretion. Various calcium channel subtypes have been shown to be coexpressed in single neurons and endocrine cells. Using the patch-clamp technique, we investigated the biophysical and pharmacological properties of calcium channels in freshly dispersed human pancreatic beta cells. Both low and high voltage activated currents were expressed, the two current types being easily distinguishable on the basis of biophysical criteria. The high voltage activated currents were not homogeneous: one component was affected by the dihydropyridine antagonist nitrendipine and the agonist Bay-K-8644; the other was insensitive to both dihydropyridines and omega-conotoxin GVIA. In line with this pharmacology, nitrendipine reduced and Bay-K-8644 increased glucose-induced insulin secretion from perifused human islets, whereas omega-conotoxin GVIA had no effect. However, about 20% of the glucose-induced insulin release was found to be resistant to high nitrendipine concentrations. These data show that human pancreatic beta cells express heterogeneous voltage-operated calcium channels, only one of which is dihydropyridine-sensitive (L type). The L type channels are clearly involved in the control of insulin secretion, but our data suggest that dihydropyridine- and omega-conotoxin GVIA-insensitive channels may also play a role in the stimulus-secretion coupling of human beta cells.

Sensitivity to dihydropyridines, omega-conotoxin and noradrenaline reveals multiple high-voltage-activated Ca2+ channels in rat insulinoma and human pancreatic beta-cells.

High-voltage-activated (HVA) Ba2+ currents of rat insulinoma (RINm5F) and human pancreatic beta-cells were tested for their sensitivity to dihydropyridines (DHPs), omega-conotoxin (omega-CgTx) and noradrenaline. In RINm5F cells, block of HVA currents by nimodipine, nitrendipine and nifedipine was voltage- and dose-dependent (apparent KD < 37 nM) and largely incomplete even at saturating doses of DHPs (mean 53%, at 10 microM and 0 mV). Analysis of slow tail currents in Bay K 8644-treated cells indicated the existence of Bay K 8644-insensitive channels that turned on at slightly more positive voltages and deactivated more quickly than Bay K 8644-modified channels. DHP Ca2+ agonists and antagonists in human beta-cells had similar features to RINm5F cells except that DHP block was more pronounced (76%, at 10 microM and 0 mV) and Bay K 8644 action was more effective, suggesting a higher density of L-type Ca2+ channels in these cells. In RINm5F cells, but not in human beta-cells, DHP-resistant currents were sensitive to omega-CgTx. The toxin depressed 10-20% of the DHP-resistant currents sparing a "residual" current (25-35%) with similar voltage-dependent characteristics and Ca2+/Ba2+ permeability. Noradrenaline (10 microM) exhibited different actions on the various HVA current components: (1) it prolonged the activation kinetics of omega-CgTx-sensitive currents, (2) it depressed by about 20% the size of DHP-sensitive currents, and (3) it had little or no effects on the residual DHP- and omega-CgTx-resistant current although intracellularly applied guanosine 5'-O-(3-thiotriphosphate) (GTP-gamma-S) prolonged its activation time course.(ABSTRACT TRUNCATED AT 250 WORDS)

Amine uptake inhibition by diosmin and diosmetin in human neuronal and neuroendocrine cell lines.

Human neuroblastoma cells of sympathetic origin have been used for studying the effects of diosmin and its metabolite diosmetin (vasotonic agent) on amine reuptake systems. Neuroblastoma cells take up 3H-dopamine in a specific and time-dependent manner. 3H-dopamine uptake was dose-dependently inhibited by the known antagonist desipramine. Diosmin did not affect 3H-dopamine uptake at concentrations as high as 1 mM. On the other hand the aglycone metabolite of diosmin, diosmetin, inhibited 3H-dopamine uptake in a dose-dependent manner (IC50 = 4 microM). Diosmetin inhibited 3H-dopamine uptake in control and differentiated neuroblastoma cells, as well as in small-cell lung carcinoma cells. Furthermore diosmetin also inhibited 3H-serotonin uptake in both cell types. These results demonstrate that some flavonoids act as antagonists of plasma membrane amine transporters at the molecular level and suggest that inhibition of amine reuptake at the level of peripheral sympathetic nerve terminals could be responsible for the increased vascular tone observed in vivo after treatment with these drugs.

omega-Conotoxin-sensitive, voltage-operated Ca2+ channels in insulin-secreting cells.

The properties of voltage-operated Ca2+ channel subtypes were investigated in insulin-secreting RINm5F cells. Two types of channels were identified: a dihydropyridine-sensitive (L-type) channel, and an omega-conotoxin-sensitive (omega-type) channel. 125I-omega-Conotoxin bound with high affinity (Kd 46.7 pM) to a saturable number of binding sites (10.3 fmol/mg of protein). Toxin binding was not antagonized by L-type channel ligands, but was sensitive to Ca2+ and neomycin. 125I-omega-Conotoxin-labeled Ca2+ channels were recognized by autoantibodies of Lambert-Eaton myasthenic patients. These antibodies are known to be specific for the neuronal omega-type channel. High-voltage-activated Ca2+ currents, investigated with the patch-clamp technique, consisted of a major dihydropyridine-sensitive (L-type) component, and a minor fraction irreversibly blocked by omega-conotoxin. Depolarizing secretagogues, such as D-glyceraldehyde and alanine, induced Ca(2+)-dependent insulin secretion, which was attenuated by omega-conotoxin. Taken together, these results show that voltage-operated Ca2+ channels in insulin-secreting RINm5F cells are heterogeneous and, in particular, that an omega-type channel, pharmacologically, immunologically and electrophysiologically similar to the neuronal omega-type channel, is also expressed in endocrine cells where it might have a role in the control of hormone secretion.

Physiopathology of neuronal voltage-operated calcium channels.

Voltage-operated calcium channels are multimeric transmembrane proteins crucially involved in control of calcium homeostasis. Multiple types of voltage-operated calcium channels have been described in both the nervous system and peripheral tissues. Different channels can be classified according to either their biophysical properties or their pharmacology, biochemical and molecular structure, and localization and functional role. Concentrating on neuronal cells, this paper reviews the different properties of low- and high-voltage activated channels, as well as various attempts to subdivide high-voltage activated channels into different subtypes (L, N, omega, P, etc.). The availability of selective drugs (such as dihydropyridines) and natural toxins (such as omega-Conotoxin, omega-agatoxin, and funnel-web spider toxins), which bind to specific channel subtypes, has greatly helped in channel classification. The emerging view is that there are many members of the family of voltage-operated calcium channels, each with its own molecular structure, a different pharmacology, a different localization, and possibly a different physiological role. Different calcium subtypes are selectively affected in human and animal diseases. The use of omega-Conotoxin has led to identification of the channel subtype (omega) specifically affected in Lambert-Eaton myasthenic syndrome (a human disease of neurotransmission), and has permitted development of new diagnostic approaches to the disease.