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We define the weighted relative p(.)-capacity and discuss its properties in the space W ϑ 1 , p (.) ( R n) . Also, we investigate some properties of the weighted variable Sobolev capacity. It is shown that there is a relation between these two capacities. Moreover, we introduce the notion of thinness related to this newly defined relative capacity and prove an equivalence statement for this thinness. [ABSTRACT FROM AUTHOR]

Purpose: Prematurity is the most common cause of infant mortality and morbidity. To prevent this, the timing of parturition and its mechanisms should be understood. It is likely that inhibitor CD94/NKG2A positive decidual natural killer cells (uNK) provide for the continuation of pregnancy. Here, we aimed to evaluate whether CD94/NKG2A positive uNK cells are highest in elective cesarian section (C/S) (suggesting ongoing gestation), moderate in normal full-term birth, and lowest in pre-eclamptic parturition.Methods: Of 48 pregnant women, 21 C/S, 16 normal, and 11 pre-eclamptic deliveries were included in this study. Five placentas in each group were assigned randomly. After staining, the volumetric analysis of the placental villi and villous blood vessels was performed via the Cavalieri principle. The CD94/NKG2A positive uNK cells were counted using the physical disector method.Results: The gestation periods and birth weights of the pre-eclamptic deliveries were lower than those of the other two groups. Additionally, the villi and villous vascular volumes were lowest in the pre-eclamptic placentas. As proposed in our hypothesis, the inhibitor CD94/NKG2A positive uNK cells were the highest in the C/S, moderate in the normal, and lowest in the pre-eclamptic placentas.Conclusions: These data suggest that CD94/NKG2A positive uNK cells are related with the continuation of pregnancy, and that our human model could be used to search for parturition-timing machinery. We believe that CD94/NKG2A positive uNK cells are also related to the timing of birth. [ABSTRACT FROM AUTHOR]

The Notch signaling pathway is an ubiquitous cell-cell interaction mechanism, which is essential in controlling processes like cell proliferation, cell fate decision, differentiation or stem cell maintenance. Recent data have shown that Notch signaling is RBP-Jκ-dependent in melanocytes, being required for survival of these pigment cells that are responsible for coloration of the skin and hairs in mammals. In addition, Notch is believed to function as an oncogene in melanoma, whereas it is a tumor suppressor in mouse epidermis. In this study, we addressed the implication of the Notch signaling in the development of another population of pigment cells forming the retinal pigment epithelium (RPE) in mammalian eyes. The constitutive activity of Notch in Tyrp1::NotchIC/° transgenic mice enhanced RPE cell proliferation, and the resulting RPE-derived pigmented tumor severely affected the overall eye structure. This RPE cell proliferation is dependent on the presence of the transcription factor RBP-Jκ, as it is rescued in mice lacking RBP-Jκ in the RPE. In conclusion, Notch signaling in the RPE uses the canonical pathway, which is dependent on the transcription factor RBP-Jκ. In addition, it is of importance for RPE development, and constitutive Notch activity leads to hyperproliferation and benign tumors of these pigment cells. [ABSTRACT FROM AUTHOR]

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The anatomical variations of Sylvian vein and cistern were investigated during the pterional approach in 230 patients with 276 aneurysms of anterior circulation arteries, that were operated on at the Neurosurgical Department of Atatürk University Medical School, Erzurum, Turkiye. All patients underwent radical surgery for aneurysm by the right or left pterional approach. The findings were recorded during surgical intervention and observed through the slides and videotapes of the operations. In our study, we surgically classified the variations of the Sylvian vein, according to its branching and draining patterns. Type I: The fronto-orbital (frontosylvian), fronto-parietal (parietosylvian) and anterior temporal (temporosylvian) veins drain into one sylvian vein. Type II: Two superficial Sylvian veins with separated basal vein draining into the sphenoparietal and Rosenthal's basal vein. Type III: Two superficial Sylvian veins draining into the sphenoparietal and the superior petrosal veins. Type IV: Hypoplastic superficial Sylvian vein and the deep one. Four types of Sylvian vein variations were defined as follows. The Type I was seen in 45% (n = 103), the Type II was found in 29% (n = 67), Type III was recorded in 15% (n = 34) and Type IV, or hypoplastic and deep form was discovered in 11% (n = 26) of patients. The course of the Sylvian vein was on the temporal side (Temporal Coursing) in 70 percent of the cases (n= 160), on the frontal side (Frontal Coursing) in 19% of the patients (n = 45) and in 8 percent of the cases (n= 18) in the deep localization (Deep Coursing). Only 3 percent of the cases (n = 7) showed a mixed course. The variations of the Sylvian cisterns were classified into three types, according to the relationships between the lateral fronto-orbital gyrus and the superior temporal gyrus. In Sylvian Type, the frontal and temporal lobes are loosely (Sylvian Type A, Large) or tightly (Sylvian Type B, Close and Narrow) approximated on the surface thereby covering the area of the Sylvian cistern. In frontal type, the proximal part of the lateral fronto-orbital gyrus herniated into the temporal lobe. In temporal type, the proximal part of the superior temporal gyrus herniated into the lateral fronto-orbital gyrus. The variations of the Sylvian cisterns in 230 patients were as follows: in 31% (n = 71) Sylvian Type A, in 21% (n = 48) Sylvian Type B, in 34% (n = 78) Frontal Type, and in 14% (n = 33) Temporal Type. We concluded that venous perfusion disorder of the brain is the most important factor during the pterional approach. Careful intraoperative assessment and protection of the Sylvian vein, which is a surgical pitfall, is an indispensable part of the operation. The recognition of the anatomical variations of the Sylvian vein and cistern, and the detailed knowledge of the microvascular relationships at that level will allow the neurosurgeon to construct a better and safter microdissection plan, to save time and can prevent postoperative neurological deficits. [ABSTRACT FROM AUTHOR]

This study attempts to analyse the intra-operative anatomical findings of the lenticulostriate artery (LSA) in 60 patients with middle cerebral artery (MCA) aneurysms who were operated on at the Neurosurgical Department of Atatürk University Medical School, Erzurum, Türkiye. All patients underwent radical surgery for aneurysm by the right or left pterional approach. The findings were recorded during surgical intervention using slides and videotapes of the operations. On average there were 4 (range, 1-14, total number=240) LSAs, in one hemisphere, per case with MCA aneurysm. Twenty percent of LSAs (n=48) arise from the prebifurcation part of the M segment, 65% (n=156) arise from the postbifurcation part of the M segment, and 15% (n=36) arise from the proximal part of the M segment. The great majority of the LSAs (85%, n=204) orginated along the proximal part of the MCA. Of a total of 240 LSAs, 125 (52%) originated from one single large vessel, a stem artery which then divided after 2-10 mm into many branches, 85 (35%) originated as two large proximal trunks, and 30 (13%) originated as multiple small arteries arising along the whole infero-medial wall of the M segment of MCA. We concluded that recognition of the anatomical variations of the LSA and detailed knowledge of the microvascular relationships of the MCA aneurysms, will allow neurosurgeons to construct a better and safer microdissection plan, to save time, and to prevent postoperative neurological deficits. [ABSTRACT FROM AUTHOR]

This study attempts to analyse the intra-operative anatomical findings of the recurrent artery of Heubner in 48 patients with Anterior Communicating Artery Aneurysm who were operated on at the Neurosurgical Department of Atatürk University Medical School, Erzurum, Türkiye. All patients underwent radical surgery for aneurysm by the right pterional approach. The findings were recorded during surgical intervention and through the dias and videotapes of the operations. The artery of Heubner originated from the junction of the A 1 and A 2 segments of the anterior cerebral artery (ACA) in 58%, from the A 2 segment of ACA in 23%, and from the A 1 segment of ACA 4%. It was asymmetrically taking off in 13% and hypoplastic in 2% of the cases. Three types of recurrent artery courses were defined. The type I or the superior course was seen in 71 %, the type II or the anterior course was found in 25% and type III or the posterior course was recorded in 4% of patients. We concluded that the recognition of the anatomical variations of the recurrent artery of Heubner and the detailed knowledge of the microvascular relationships of the anterior communicating artery (ACoA) complex, will allow neurosurgeons to construct a better and safer microdissection plan, to save time, and so prevent postoperative neurological deficit. [ABSTRACT FROM AUTHOR]

The authors have investigated the effect of very early irrigation of the cerebrospinal fluid (CSF) space in the haemorrhage rat model of vasospasm. Fifteen rats had basilar cistern irrigation with physiological saline for 3 hours after subarachnoid haemorrhage (SAH), and fifteen control rats had subarachnoid haemorrhage without irrigation of clot. The changes in basilar arteries diameters were determined by angiograms obtained from the rats. The post haemorrhage angiograms showed significant basilar artery spasm in both groups (P⩽0.0005, t-test). However in the last angiogram the basilar artery diameter was found to have the same value measured before subarachnoid haemorrhage in the irrigation group whereas no obvious change was observed in the control group. In the irrigation group the mean diameter of the basilar artery in the last angiogram was 0.412 mm. (0.30 mm to 0.50 mm). None of the animals, treated by cisternal irrigation, showed angiographic vasospasm while the latter group did (P⩽0.0005). Animals treated with physiological saline irrigation had a median clot grade of 0.40 (range grade 0 to 2); control rats had a median grade 2.86 (range grade 1 to 4, P<0.001, Mann-Withney U test), on the brain stem, indicating significant reduction of clot by lavage. In conclusion, performance of experimental physiological saline irrigation at a very early time after subarachnoid haemorrhage prevents the arteriographic and morphological changes of both acute and late vasospasms. [ABSTRACT FROM AUTHOR]

These experiments were designed to determine whether the abnormal glucagon response of diabetics to a glucose meal can be restored to normal by the short-term administration of exogenous insulin in amounts sufficient to produce normal and above normal plasma insulin levels. The immunoreactive glucagon (IRG) response of nine nondiabetics to oral glucose was compared with that of ten juvenile and ten adult type diabetics. In the absence of exogenous insulin, the IRG response of diabetics was strikingly different from the nondiabetics, rising paradoxically, whereas in nondiabetics there was a decline in IRG. When plasma insulin levels were raised to normal by infusion of insulin (0.06 U/kg for 2 hr), the abnormal IRG response of adult type diabetics was not improved; the IRG response of the juvenile type patients was improved, but remained abnormal. Raising plasma insulin briefly to greater than normal concentrations inproved the IRG response during the glucose meal in both groups, but in the adult group total IRG suppression was still only half that of the nondiabetics; in the juvenile type group it was reduced to the nondiabetic level, but at glucose and insulin levels far above those of nondiabetics. The results are compatible with the view that the glucose-sensing function of the A-cells is, at least in part, mediated by or requires insulin. In juvenile diabetics, the abnormality is corrected by raising plasma insulin to above normal levels; adult onset diabetics appear to be less sensitive even to large doses of insulin during a carbohydrate load. [ABSTRACT FROM AUTHOR]

There have been several studies on anosmia following operations on anterior circulation aneurysms, but no similar study has yet been reported on pituitary gland adenomas which required the transcranial approach. In this study, 38 cases with pituitary gland adenomas, for whom the pterional approach was employed, were observed retrospectively from the point of view of postoperative olfactory nerve function. In the postoperative period only one case complained of impaired sense of smell on the operated side. Eight cases objectively showed olfactory nerve disfunctions. The olfactory nerve function could be preserved at a relatively high rate of 79 per cent. This high rate, we think, resulted from the microtechnique employed as well as the relatively cautious frontal retraction which was less than 1,5 cm. [ABSTRACT FROM AUTHOR]