Tailoring of the Properties of Amorphous Mesoporous Titanosilicates Active in Acetone Condensation.

Amorphous mesoporous materials are promising as catalysts for processes involving or forming bulk molecules. In a reaction such as acetone condensation to form mesitylene, an effective catalyst should not only have a developed porous structure but also have active centers of acidic and basic types. The sol-gel approach allows one to obtain titanosilicates with such characteristics.

[Undifferentiated pancreatic carcinoma with osteoclast-like giant cells].

In the structure of malignant oncological diseases of the Russian population, pancreatic cancer (PCa) occupies the 10th place with a high mortality rate in case of late diagnosis, which is primarily due to the minimal clinical manifestations of this pathology and the absence of precancer as a potential substrate for screening. Undifferentiated pancreatic carcinoma with osteoclast-like giant cell (UC-OGC) is a rare histological variant of PCa with discussed bidirectional histogenesis (epithelial and mesenchymal), epithelial-mesenchymal transition in the tumor and variable prognosis depending on the predominant cellular component. A review of the literature reflecting debatable issues of origin, clinical and pathological characteristics and prognosis of UC-OGC, as well as a description of a clinical case is relevant due to the rare occurrence of this tumor in the routine work of pathologists and oncologists.

[THE INFLUENCE OF SHORT-TIME CEREBRAL ISCHEMIA ON PIAL VESSELS ADRENOREACTIVITY IN RATS].

Reactivity of pial vessels in response to a brain surface irrigation by norepinephrine solution in rats, subjected to transient global cerebral ischemia (2VO+hypo model), was investigated. Four different groups of rats at 2, 7, 14 or 21 days after ischemia were subjected to microvascular studies using in vivo video microscopy method. The diameter changes of pial arteries and veins in response to norepinephrine were measured.

Changes in Cerebral Blood Flow in the Postischemic Period.

Experiments on Wistar rats showed that blood flow in the cortex and subcortical brain structures was not completely restored within 21 days after transient ischemia caused by bilateral carotid artery occlusion with controlled hypotension. After 7 days of reinfusion, the end-diastolic blood flow velocity increases with simultaneous decrease in pulsation index, which indicates the decrease in peripheral vascular resistance. During the following 14 days, peripheral blood resistance increases, as was seen from the increased peak systolic blood flow velocity, mean blood flow velocity over the heart cycle, and pulsation index.

Postischemic Responsiveness of Pial Vessels to Hypercapnia.

Reactions of pial vessels to hypercapnia were studied in Wistar rats one week after global cerebral ischemia. In ischemic rats, the responsiveness of pial vessels to hypercapnia was diminished, which promoted a decrease in cerebral perfusion reserve. Changes in vascular responsiveness in the arterial and venous subdivisions of the vascular bed were observed and probably resulted from ischemia-provoked down-regulation of the vascular tone.

[Pancreatic acinar cell adenoma].

The paper describes two cases of acinar cell adenoma, a rare tumor of the pancreas, diagnosed in two 70- and 58-year-old women after surgery. It presents a histological description of the tumor and the results of immunohistochemical tests performed.

[The gastrointestinal stromal tumor of the stomach in child: characteristic of diagnostics].

The observation of stromal gastric tumor of 12 years old girl has been investigated. The diagnostics was carried out on tumor biopsy taken by a laparoscopy. An evident edema of stroma caused "pseudo-papillary" organization of epithelioid cell neoplasm prevented the right diagnosis established only by immunohistochemical staining of CD117 and CD34 markers.

[Expression of Ki-67, p53, bcl-2, estrogen receptors alpha in patients with clear cell renal carcinoma and epidermal growth factor receptor mutation].

Three hundred and thirty-six cases of clear-cell renal carcinoma (CCRC) were examined for epidermal growth factor receptor (EGFR) mutation: exon 19 deletion and L858R mutation in exon 21 of the EGFR gene. The expression of Ki-67, bcl-2, p53, and estrogen receptors alpha was studied in CCRC with EGFR mutation. There were 4 cases of CCRC with EGFR exon 19 deletion.

[Association of insulinase gene polymorphisms with type 2 diabetes mellitus in patients from the Moscow population].

Association of 13 single nucleotide polymorphisms (SNPs) of insulinase (IDE) gene with type 2 diabetes mellitus (T2D) in the Moscow population has been examined. Three polymorphic markers (rs7078413, rs7899603, and rs551266) associated with the risk of T2D development have been revealed. Allele and genotype frequency distribution for these three markers differed significantly only in the sample of females between T2D patients and control individuals, while only in case of rs7078413 SNP genotype frequencies varied significantly in the total population.

[Dependence of constrictor and dilator humoral responses of arteries and veins in the small intestine on calcium ions entering vascular myocytes].

Verapamyl administered to the intestine circulation in the dose evoking no shifts in the arterial and venous resistance or in the vascular capacity, decreased 2- or 3-fold both the constrictor and dilatory responses of the arterial vessels. Against the background of Verapamyl, noradrenaline and isoproterenol did not practically change either capacity or resistance in the veins. Responses of veins to angiotensin II increased 10-fold and more, whereas they were absent after administration of atropine into the intestine circulation.

[Resistance and capacity function of blood vessels of the brain during activation of its cholinergic mechanisms].

Blood from the cat donor was perfused into the haemodynamically isolated cat brain. The changes of the vascular resistance and their capacity during the pharmacological activity of the endogenic cholinergic mechanism on the introduction of phosphacol into the bloodstream were investigated. Research has shown that the reduction of the activity of cholinergics leads to a decrease in pressure in the arteries of the brain and to an increase of the intercellular fluid absorption, caused by the neurogenic cholinergic influences.

[Macro- and microcirculatory shifts in the brain of cats during hypoxia and hypercapnia].

The cat hemodynamically isolated brain, when transferred from the air artificial ventilation to the respiration with 10% oxygen or 5-10% carbon dioxide mixtures, developed a decrease in vascular resistance and an increase in the venous outflow. The capillary hydrostatic pressure dropped and the intercellular fluid absorption reduced in both cases. The brain capillary filtration coefficient increased in hypoxia and decreased in hypercapnia.

[Role of subcortical structures in the development of vascular and neuronal responses of the brain to hypoxia].

Spontaneous impulse activity, local blood flow and oxygen available were recorded in hypoxia in intact and in neuronally isolated cortex in cats. The hypoxia affected all three parameters. The increase in firing rate of spontaneously active neurons was delayed in isolated cortex as compared with the intact one, and the duration of activation phase was prolonged.

[Changes in the hydration of the cerebral interstitial space and their role in the development of vascular reactivity].

Augmentation of the cerebral venous pressure in anesthetized cats whose brain was naturally perfused under the constant arterial pressure, caused a transvascular filtration of fluid into the brain tissue. Capillary filtration coefficient was 0.099 +/- 0.

[Effect of an increase in intracranial pressure on transvascular fluid movement in the brain].

Transvascular fluid exchange was studied in the haemodynamically isolated brain in the hermetically closed cranium. The brain was perfused with the constant blood flow under the condition of the cross-perfusion from anesthetized donor-cats. The rise of the intracranial pressure was accompanied by the liquor resorption and increasing of venous outflow.

[Transvascular fluid movement into the brain in response to an increase in venous pressure].

An increase in pressure of the venous outflow under conditions of perfusion with constant blood flow of hemodynamically isolated brain, led to filtration of fluid from the cerebral vascular bed in anesthetized cats. Velocity of the transvascular translocation of fluid was proportional to the pressure increase by 50, 75 and 100 mm Hg in cerebral veins. The capillary filtration coefficient (CFC) was about 0.

[Conjunct changes in the resistance and engorgement of the cerebral vessels in shifts in the blood gas composition].

In anesthetized cats, under perfusion and with constant volume of the hemodynamically isolated brain, hypercapnia and hypoxia led to a decrease of cerebral vessels resistance and to a reduction of the brain blood flow, whereas a decrease in the PCO2 and an increase in the PO2 in the blood exerted on opposite effect. The different responses of the vessels had some similar features in respect to threshold changes of the PCO2 and PO2, to potentiation of effects of both parts of the brain vascular system on increased shifts of the blood gas tension, to greater sensitivity of both parts to PCO2 changes, to effect of the blood gas tension on reactivity of both parts to noradrenaline. The authors suggest a possibility of alterations of the filter-absorption interrelationships in the brain due to different responses of arterial and venous vessels to changes of the blood gas tension.

[Influence of the sympathetic nervous system on the electrical activity of the neuronally isolated cerebral cortex].

Bilateral transection of the pregangiolinic sympathetic cervical fibers and electrical stimulation of ipsilateral cranial and of the cervical sympathetic nerve originated reactions differing in strength and latency in intact hemisphere and in neuronally isolated neocortex, but having common origin mainly due to changes in the capacities of the delta--and theta--potentials. The direct nervous influences on electrical activity of the neuronally isolated neocortex through sympathetic fibers passing along the blood vessels, seems to be insufficient.