Peritubular dentin lacks piezoelectricity

Dentin is a mesenchymal tissue, and, as such, is based on a collagenous matrix that is reinforced by apatite mineral. Collagen fibrils show piezoelectricity, a phenomenon that is used by piezoresponse force microscopy (PFM) to obtain high-resolution images. We applied PFM to image human dentin with 10-nm resolution, and to test the hypothesis that zones of piezoactivity, indicating the presence of collagen fibrils, can be distinguished in dentin. Piezoelectricity was observed by PFM in the dentin intertubular matrix, while the peritubular dentin remained without response. High-resolution imaging of chemically treated intertubular dentin attributed the piezoelectric effect to individual collagen fibrils that differed in the signal strength, depending on the fibril orientation. This study supports the hypothesis that peritubular dentin is a non-collagenous tissue and is thus an exception among mineralized tissues that derive from the mesenchyme.     

Sodium-channel blockers might contribute to the prevention of ventricular tachycardia in patients with long QT syndrome type 2: a description of 4 cases

Four patients with long QT type 2, aged 11 to 18 years from unrelated families, with recurrent syncope and polymorhic ventricular tachycardia were studied. Long QT syndrome was diagnosed in these children at ages 4 to 7 years. Syncope, QT prolongation on electrocardiogram (corrected QT interval ≥ 490 milliseconds), notched T-wave morphology, bradycardia, and polymorphic ventricular arrhythmia were found in all of the patients. The KCNH2-L586M; KCNH2-G604S, KCNH2-L1045F; and a combined mutation KCNH2 T613M + SCN5A R190G were genotyped. Syncope, implantable cardioverter-defibrillator shocks, and tachycardia persisted in these patients, although they were receiving a full dose of β-blocker therapy. Adding a sodium-channel blocker (IC class) led to a reduction in the polymorphic ventricular arrhythmia. No syncope episodes were registered during the patients' 8 to 60 months of follow-up on the combined antiarrhythmic therapy. Further studies are needed to better define the possible role of sodium-channel blockers in patients with long QT type 2.     

Intraabdominal hypertension and secondary abdominal compartment-syndrome in the patient with craniopharyngioma in postoperative period

Currently problem of intraabdominal hypertension in patients with brain tumors is practically uninvestigated. Authors describe a case of complicated course of early postoperative period in the patient with craniopharyngioma due to secondary abdominal compartment-syndrome. Causes of intraabdominal hypertension in patients with CNS lesions requiring intensive care are analyzed. Risk factors of intraabdominal hypertension deserving attention in management of patients in neurolCU are determined.     

Comparative analysis of surgical and medical treatment of macroprolactinoma of different localization

The authors performed comparative analysis of results of primary surgical and medical treatment of 306 patients with macroprolactinoma. The series included 178 male and 128 female patients. The tumor was endosellar in 48 cases, endosuprasellar in 94, invaded skull base in 164. The paper demonstrates that according to dynamics of visual function, neurological and hypopituitary symptoms, and probability of prolactin level normalization, treatment with cabergoline has significant advantages in comparison to surgery. Only surgical treatment of endosellar prolactinomas can compete with conservative treatment. After these operations no postoperative complications were observed, normalization of prolactin level was present in 67% of cases, and these results did not differ from results of medical treatment (71%). In case of extrasellar grown of macroprolactinoma, especially invading skull base, primary medical therapy is preferred.     

Therapy of acute massive blood loss in a hemophilic patient: case report

A case is reported of management of massive intraoperative blood loss in a male patient with severe hemophilia. Extirpation of hip pseudotumor with one-stage osteosynthesis with an intramedullary joint-pin in a 43 year old male patient was accompanied with 7.5 l blood loss. The infusion-transfusion therapy (ITT) contained transfusion media about 1/3 of the total volume, fresh-frozen plasma and erythrocyte-containing media were used 1:1. Infusion solutions consisted of balanced polyelectrolytic solutions, hydroxyethylated starches 130/0.4, hyperchaes. Intraoperative normovolemic hemodilution and reinfusion of wound blood were made (CellSaver). ITT target markers were standard hemodynamics control tests. Hemostasis monitoring was conducted with thromboelastography. Complex ITT based on modern principles of clinical transfusiology provided a complete and safe compensation of massive intraoperative blood loss in a patient with severe hemophilia.     

Chronology and evolution of temporal lobe epilepsy and endocrine reproductive dysfunction in women: relationships to side of focus and catameniality

The current study was carried out to determine the possible associations between side of focus, catameniality, reproductive dysfunction (RD), and chronology variables for epilepsy and concomitant RD in women. Eighty women of childbearing potential with temporal lobe epilepsy were included in the study. Catamenial epilepsy was observed mainly in women with left-sided foci, and a noncatamenial pattern in women with right-sided foci. Left-sided foci were associated with polycystic ovary syndrome, and right-sided foci with hypogonadotropic hypogonadism. Catamenial epilepsy with right-sided foci was associated with longer duration of epilepsy (P=0.021), trend toward earlier age at onset of epilepsy, and trend toward longer interval between onset of epilepsy and onset of RD compared with catamenial epilepsy with left-sided foci. On the other hand, noncatamenial epilepsy with right-sided foci was characterized by a shorter interval between onset of epilepsy and onset of RD in comparison with noncatamenial epilepsy with left-sided activity (P=0.03). In addition, comparison of patients with right-sided foci with catamenial and noncatamenial patterns of seizures revealed earlier age of epilepsy onset (P=0.049), longer duration of epilepsy (P=0.017) and of RD (P=0.036), and longer interval between onset of epilepsy and onset of RD (P=0.048) in patients with catamenial epilepsy. From an evolutionary point of view, catamenial epilepsy with right-sided focal activity seems to be the oldest subtype.