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1.
The topography of the auriculotemporal nerve (ATN) root system is the main criterion of this nerve classification. Previous publications indicate that ATN may have between one and five roots. Most common is a one- or two-root variant of the nerve structure. The problem of many publications is the inconsistency of nomenclature which concerns the terms “roots”, “connecting branches”, or “branches” that are used to identify the same structures. This study was performed on 80 specimens (40 adults and 40 fetuses) to propose a classification based on: (i) the number of roots, (ii) way of root division, and (iii) configuration of interradicular fibers that form the ATN trunk. This new classification is a remedy for inconsistency of nomenclature of ATN in the infratemporal fossa. This classification system has proven beneficial when organizing all ATN variants described in previous studies and could become a helpful tool for surgeons and dentists. Examination of ATN from the infratemporal fossa of fetuses (the youngest was at 18 weeks gestational age) showed that, at that stage, the nerve is fully developed. 相似文献
2.
Y Touitou A Auzeby A Bogdan 《The Journal of steroid biochemistry and molecular biology》1990,37(2):279-284
The presence of 17 alpha-hydroxylase in rodent adrenals is debated. The presence in blood of mice of 11-deoxycortisol together with the absence of cortisol is well known. We demonstrated here the in vitro synthesis of 17 alpha-hydroxyprogesterone and cortisol from [3H]progesterone in rat and mouse adrenals. We have shown that these syntheses represented 45 and 28% of those of 11-deoxycorticosterone and corticosterone, respectively, from progesterone. These data clearly suggest the presence of a 17 alpha-hydroxylase activity in vitro in these rodents adrenals. In addition, a noticeable synthesis of cortisol (0.87-1.57% per mg tissue, i.e. 52-64% per incubation flask) from 11-deoxycortisol was also observed and was inhibited by 0.1-0.3 mumol of Metyrapone and SKF 12185. These results allow to underline that the adrenals of rat and mouse, two species commonly used in laboratory experiments, may be used for in vitro investigations on cortisol metabolism from exogenous radioactive precursors. 相似文献
3.
17-Hydroxyprogesterone is a well-known precursor of androstenedione in adrenal biosynthesis. This study using sheep adrenal incubations demonstrates that 11-deoxycortisol, the precursor of cortisol synthesis, also can be a precursor of androstenedione. Indeed, our data show that androstenedione synthesis is negatively correlated to the synthesis of cortisol and cortisone. This fact allowed us to infer that this new pathway is closely related to the activity of the 11 beta-hydroxylase that is responsible for the synthesis of cortisol. Indeed, when the activity of this enzyme is impaired, 11-deoxycortisol follows the pathway that leads to androstenedione synthesis in the adrenals. This pathway could explain, at least in part, the marked increase of androstenedione observed in congenital adrenal hyperplasia due to 11 beta-hydroxylase deficiency. 相似文献
4.
Suppressive effect of cyclosporin A on the development of Leishmania tropica-induced lesions in genetically susceptible BALB/c mice 总被引:9,自引:0,他引:9
W Solbach K Forberg E Kammerer C Bogdan M R?llinghoff 《Journal of immunology (Baltimore, Md. : 1950)》1986,137(2):702-707
The effect of cyclosporin A (CyA) application on the development of cutaneous lesions was analyzed in genetically susceptible BALB/c mice infected s.c. with Leishmania tropica promastigotes. Daily i.p. injections of CyA, beginning 2 days before or at the day of the infection, dose dependently inhibited the development of parasite-induced lesions; no effect on the lesions was observed, however, if CyA application was started 14 days after the infection. Cessation of CyA administration after having successfully suppressed the cutaneous lesions for a period of 42 days, resulted in the development of lesions within 3 days. CyA had no inhibitory effect on lesions developing in L. tropica infected hypothymic BALB/c nu/nu mice. CyA or CyA-containing mouse serum did not directly affect the viability and the growth rate of L. tropica promastigotes, suggesting that the effect of the agent was imposed on the cells participating in the formation of the cutaneous lesions. Quantitative analysis of the cell distribution in the spleens of infected mice revealed that CyA markedly suppressed the infection-associated numerical increase of splenocytes. Within the Thy-1+ lymphocyte compartment, CyA had its most pronounced effect on the Lyt-1+ T lymphocyte subset. Early in the disease, the frequency of splenic cells proliferating in response to L. tropica antigen in vitro was clearly inhibited by CyA; in the later stages of the infection, however, this effect could not be observed, indicating the presence of L. tropica-inducible T cells being relatively resistant to CyA. Taken together, our findings indicate that CyA reversibly inhibits or delays the parasite-induced expansion of Lyt-1+ splenic T lymphocytes, and thus suppresses the biological function of those T cells that are instrumental for the formation of cutaneous lesions in L. tropica-infected BALB/c mice. 相似文献
5.
A combined method is described for the determination of various metabolites from a single tissue sample of the brain. It comprises a quick inactivation of cerebral enzymes by microwave irradiation, easy separation of the desired brain regions, and perchloric acid extraction of tissue substances, which are assayed either by specific enzymatic techniques or by HPLC with electrochemical detection. The obtained values of most energy and neurotransmitter metabolites in the brain are in agreement with those reported using other methods. However, this technique, in contrast to the brain freezing in vitro or freeze-blowing, provides a more efficient procedure for rapid arrest of cerebral metabolism even in the deep brain structures and is therefore suitable for detection of early changes particularly those occurring in experimental pathological conditions such as ischemia. 相似文献
6.
Djordje Boskov Mirjana Jocic Ksenija Jovanovic Milos Ljubisavljevic Radmila Anastasijevic 《Biological cybernetics》1994,71(4):341-348
Spike discharges of skeletomotor neurons innervating triceps surae muscles elicited by white noise modulated transmembrane
current stimulation and muscle stretch were studied in decerebrated cats. The white noise modulated current intensity ranged
from 4.3 to 63.2 nA peak-to-peak, while muscle stretches ranged from 100 μm to 4.26 mm peak-to-peak. The neuronal responses
were studied by averaging the muscle length records centered at the skeletomotor action potentials (peri-spike average, PSA)
and by Wiener analysis. Skeletomotor spikes appeared after a sharp peak in PSA of the injected current, preceded by a longer-lasting
smaller wavelet of either depolarizing or hyperpolarizing direction. The PSA amplitude was not related to the injected current
amplitude nor showed any differences related to the motor unit type. The PSA amplitudes were virtually independent of the
stretching amplitude σ, after an initial increase with stretching amplitudes in the range of 15–40 μm (S.D.), or 100–270 μm
peak-to-peak.Analyses of cross-spectra indicated a small or absent increase in gain with frequency in response to injected
current, but about 20 dB/decade in the range 10–100 Hz in response to muscle stretch. The peaks of both Wiener kernels in
response to current injection appear to decrease with the amplitude of injected current, but this decrease was not statistically
significant. The narrow first-order kernels suggest that the transfer function between the current input and spike discharge
is lowpass with a wide passband, i.e. there is very little change in dynamics. The values of the second-order kernels appear
to be nonzero only along the main diagonal. This is characteristic of a simple Hammerstein type cascade, i.e. a zero memory
nonlinearity followed by a linear system. Small values of second-order kernels away from the origin and narrow first-order
kernels suggest that the linear cascade contributes very little to the overall dynamic response.In contrast to Wiener kernels
found in response to current injection, the Wiener kernels in response to stretch showed a decreasing trend with stretch amplitude.
The size of the second-order kernels decreased to a somewhat larger extent with input amplitude than that of the first-order
kernels, indicating an amplitude-dependent nonlinearity. Overall, the transformation between length and spike output was described
as an LNNL cascade with second-order nonlinearities.
Received: 1 April 1993/Accepted in revised form: 24 March 1994 相似文献
7.
Adrian Bogdan Tigu Catalin Sorin Constantinescu Patric Teodorescu David Kegyes Raluca Munteanu Richard Feder Mareike Peters Ioana Pralea Cristina Iuga Diana Cenariu Andra Marcu Alina Tanase Anca Colita Rares Drula Jon Thor Bergthorsson Victor Greiff Delia Dima Cristina Selicean Ioana Rus Mihnea Zdrenghea Diana Gulei Gabriel Ghiaur Ciprian Tomuleasa 《Journal of cellular and molecular medicine》2023,27(19):2864-2875
Acute megakaryoblastic leukaemia (AMkL) is a rare subtype of acute myeloid leukaemia (AML) representing 5% of all reported cases, and frequently diagnosed in children with Down syndrome. Patients diagnosed with AMkL have low overall survival and have poor outcome to treatment, thus novel therapies such as CAR T cell therapy could represent an alternative in treating AMkL. We investigated the effect of a new CAR T cell which targets CD41, a specific surface antigen for M7-AMkL, against an in vitro model for AMkL, DAMI Luc2 cell line. The performed flow cytometry evaluation highlighted a percentage of 93.8% CAR T cells eGFP-positive and a limited acute effect on lowering the target cell population. However, the interaction between effector and target (E:T) cells, at a low ratio, lowered the cell membrane integrity, and reduced the M7-AMkL cell population after 24 h of co-culture, while the cytotoxic effect was not significant in groups with higher E:T ratio. Our findings suggest that the anti-CD41 CAR T cells are efficient for a limited time spawn and the cytotoxic effect is visible in all experimental groups with low E:T ratio. 相似文献
8.
Bogdan Korica 《Plant Systematics and Evolution》1955,102(2-3):339-364
Zusammenfassung Die ArtAsperula scutellaris
Vis. wurde diagnostisch erweitert und genauer präzisiert. Sie zerfällt in folgende Sippen: die typische Form ssp.illyrica
Korica, welche zwei Varietäten umfaßt (var.veleensis
Korica und var.montenegrina
Korica), und ssp.ramiflora
Korica mit einer Varietät (var.albanica
Korica).Asperula scutellaris
Vis. ist ein mediterran-illyrischer Endem und einer der bemerkenswertesten Vertreter der jugoslawischen und albanischen Karstflora. Im mittleren Teil Albaniens tritt sie auch auf Serpentinen auf.In pflanzengeographischem Sinn sind vier Entwicklungsgebiete dieser Art zu unterscheiden: das Entwicklungsgebiet der Veleplanina in der Herzegowina (var.veleensis), das montenegrinische Entwicklungsgebiet (var.montenegrina) mit dem ursprünglichen Ausbildungszentrum in der weiteren Umgebung der Stadt Cetinje, endlich das nordalbanische Entwicklungsgebiet im Stromgebiet der Flüsse Cijevna und Drim. Diese drei Gebiete sind von submediterranem Charakter, das mittelalbanische Entwicklungsgebiet in der Gegend des Flusses Shkumbi (var.albanica) weist dagegen einen mediterranisch-submediterranischen Charakter auf.Auf Grund der festgestellten Tatsachen des heutigen Standes der Verbreitung der einzelnen Sippen dieser Art sowie auf Grund der charakteristischen geomorphologischen und klimatischen Differenzen zwischen den monomorphen Sippen (ssp.illyrica), welche an die Küstenteile des beschriebenen Areals gebunden sind, und den polymorphen Übergangsformen der submediterranen Sippen, welche in den kontinentalen Teilen des Areals überwiegen (submediterrane klimatische Einflüsse), folgt, daß die typischen Formen (ssp.illyrica) im submediterranen Gebiet phylogenetisch nicht mit jenen des mediterranen Gebietes identisch sind. 相似文献
9.
Modulation of Intracellular Cyclic AMP Levels by Different Human Dopamine D4 Receptor Variants 总被引:15,自引:0,他引:15
Vida Asghari Suparna Sanyal Saskia Buchwaldt rew Paterson Vera Jovanovic Hubert H. M. Van Tol 《Journal of neurochemistry》1995,65(3):1157-1165
Abstract: To investigate whether polymorphic forms of the human dopamine D4 receptor have different functional characteristics, we have stably expressed cDNAs of the D4.2, D4.4, and D4.7 isoforms in several cell lines. Chinese hamster ovary CHO-K1 cell lines expressing D4 receptor variants displayed pharmacological profiles that were in close agreement with previous data from transiently expressed D4 receptors in COS-7 cells. Dopamine stimulation of the D4 receptors resulted in a concentration-dependent inhibition of the forskolin-stimulated cyclic AMP (cAMP) levels. The potency of dopamine to inhibit cAMP formation was about twofold reduced for D4.7 (EC50 of ∼37 n M ) compared with the D4.2 and D4.4 variants (EC50 of ∼16 n M ). Antagonists block the dopamine-mediated inhibition of cAMP formation with a rank order of potency of emonapride > haloperidol = clozapine ≫ raclopride. There was no obvious correlation between the efficacy of inhibition of forskolin-stimulated cAMP levels and the D4 subtypes. Dopamine could completely reverse prostaglandin E2 -stimulated cAMP levels for all three D4 receptor variants. Deletion of the repeat sequence does not affect functional activity of the receptor. The data presented indicate that the polymorphic repeat sequence causes only small changes in the ability of the D4 receptor to block cAMP production in CHO cells. 相似文献
10.
Bogdan Lesyng Wolfram Saenger 《Biochimica et Biophysica Acta (BBA)/General Subjects》1981,678(3):408-413
Hydration of macromolecules and the structure of water of crystallization are not understood in detail because in these complex systems. H-atoms cannot be located and the hydrogen bonding schemes are not known. X-ray and neutron diffraction studies on a hydrated oligosaccharide, α-cyclodextrin 6H2O, ((C6H10O5)6·6H2O), crystals forms A and B, gave insight into the chain-like and circular arrangement of hydrogen bonds. In the circles, homodromic (unidirectional) and antidromic (counter-running) orientation of five to six hydrogen bounds is observed. PCILO calculations showed that homodromic circles and chains are approx. 8% per hydrogen bond more stable than antidromic circles, that the changes in electronic charges on H and O atoms are greater in homo than in antidromic systems and that the dipole moments are only approx. 3 D in the homodromic circles but 6–8 D in chain-like and antidromic arrangement. These results have been interpreted in terms of cooperative effect. Circular systems are considered as structural elements in hydration shells of macromolecules and in the assembly of ‘flickering’ water clusters. 相似文献