255 research outputs found
Autonomic cardiac nerves: literature review
The aim of this paper was to summarise the knowledge about the autonomic cardiac innervation. It is generally known, that the cardiac nervous system consists of nerve plexoganglionic structures located mostly around the strategic regions of the heart. They consist of two main types of components: parasympathetic neurons, which exert an inhibitory effect, and sympathetic postganglionic nerve fibres, which stimulate the cardiac conduction system, and myocardial cells. However, many authors describe that cardiac ganglia contain various populations of neurons. The largest group are classical cholinergic neurons. The second group of cardiac neurons are cells of dual, cholinergic-adrenergic character. There is also subpopulation of small intensely fluoroscent cells of typically adrenergic phenotype. Moreover, many authors indicated the presence of various neurotransmitters in various combinations. In this way, the neurons in cardiac ganglia are a neurochemical complex beyond the classical vision of parasympathetic ganglia
Adrenergic and cholinergic innervation of the atrioventricular valves in chinchilla (Chinchilla laniger)
The arrangement of autonomic fibres was studied in the cardiac atrioventricular valves of small chinchillas. The dissected valves were stained entirely using the modified histochemical acetylcholine esterase technique (AChE) and the SPG-De la Torre method. Double immunocytochemical staining was also used for the expression of vesicular acetylcholine transporter (VAChT) and dopamine beta hydroxylase (DBH). The study showed the presence of both cholinergic and adrenergic fibres, forming a kind of network on all cusps of both valves. The adrenergic network is always more strongly represented than the cholinergic network. The cholinergic nerve network of the “parietal” part formed mainly the parallel arrangement. As we move towards the free parts of the cusps, the arrangement becomes netted and radiant. The adrenergic fibres formed only the netted arrangement, which was the most dense in the peripheral (parietal) part of the cusps. Some of the fibres in the vicinity of tendinous cords extended as far as the papillary muscles. Double immunocytochemical tests confirmed the presence and distribution of DBH- and VAChT-positive fibres. Some fibres (especially within the tendinous cords) show VAChT and DBH colocalisation
Four left renal arteries — a rare variant of kidney arterial supply
We describe the arterial supply of a human kidney harvested post-mortem from a 75-year-old female volunteer body donor. The kidney was analysed with con- trast-enhanced computed tomography (CT), and corrosion casting was used to reveal the kidney’s angio-architecture. In the left kidney, we observed four renal arteries, each originating directly from the abdominal aorta. Three renal arteries, including the main renal artery, coursed through the renal hilum, and the fourth renal artery reached the lower kidney pole. The supply areas of each of the four renal arteries were analysed with a three-dimensional reconstruction of CT images and with corrosion casting. There were no clear boundaries between the areas supplied by the four renal arteries because their branches overlapped in most kidney segments.
Anatomical and histological data on the ciliary ganglion in the Egyptian spiny mouse (Acomys cahirinus Desmarest)
The morphology and topography of the ciliary ganglion in the Egyptian spiny
mouse were studied with use of histochemical and histological techniques. The
ciliary ganglion of the Egyptian spiny mouse consisted of between 3 and 4 agglomerations
of nerve cells. The largest was situated at the point where the
ventral branch of the oculomotor nerve divides into two branches. The next two
smaller aggregations were located on the superior and lateral surfaces of the
optic nerve where it crossed the oculomotor nerve. From the main agglomerations
of neurocytes arose between 3 and 4 intensively stained postganglionic
cholinergic fibres. These followed the optic nerve to the eyeball. On the crosssections
of these bundles small agglomerations of neurocytes were observed.
These decreased in size to only 2 or 3 cells towards the sclera. The ganglionic
neurocytes in the largest ganglion varied from 15 to 30 µm in diameter. They
were distributed uniformly over the whole surface of the sections. All the ganglia
had connective capsules
Rare morphological variants of the bones: epicondylar processes, metopic suture and Wormian bones in XVIII century skeleton
Background: Analysis of the female skeleton from the 18th century revealed a collection of morphological changes.
Materials and methods: Anthropological evaluation and dental X-ray techniques allowed the age to be determined at 12–13 years.
Results: The distal parts of the both humerus bones had distinct, supracondylar processes of about 5 mm at the medial-lateral surface. The frontal bone had a well-preserved metopic suture along the entire length of the squama. There were also two Wormian bones (Inca bones), asymmetrical mastoid foramen, and only left non-obliterated condylar canal.
Conclusions: The skull measurements allowed the cranial index to be determined — 93.5 (brachycephalia) and height-length index — 98.6 (akrocephalus). Moreover, X-ray analysis of incomplete dentition was made
Determination of the Defining Boundary in Nuclear Magnetic Resonance Diffusion Experiments
While nuclear magnetic resonance diffusion experiments are widely used to
resolve structures confining the diffusion process, it has been elusive whether
they can exactly reveal these structures. This question is closely related to
X-ray scattering and to Kac's "hear the drum" problem. Although the shape of
the drum is not "hearable", we show that the confining boundary of closed pores
can indeed be detected using modified Stejskal-Tanner magnetic field gradients
that preserve the phase information and enable imaging of the average pore in a
porous medium with a largely increased signal-to-noise ratio.Comment: 13 pages, 2 figure
CONTRAST-ENHANCED ULTRASOUND MONITORING OF PERFUSION CHANGES IN HEPATIC NEUROENDOCRINE METASTASES AFTER SYSTEMIC VERSUS SELECTIVE ARTERIAL 177LU/90Y-DOTATOC AND 213BI-DOTATOC RADIOPEPTIDE THERAPY
Radiopeptide therapy with beta emitter labeled 177Lu/90Y- DOTA(0)-Phe(1)-Tyr(3)-octreotide (DOTATOC) and more recently
also alpha emitting 213Bi-DOTATOC are promising new treatments for neuroendocrine tumors. No early predictors for treatment
response have been recognized and tumor-shrinkage after radiation therapy appears slowly. In some solid tumors a decline in tumor
perfusion was found predictive of final treatment response but the gold standard multiphase computed tomography (CT) has
a high radiation burden. Therefore we evaluated the ability of contrast-enhanced ultrasound (CEUS) to evaluate tumor perfusion
as a response criteria. Materials and Methods: 14 patients with hepatic neuroendocrine tumor (NET) metastases were enrolled
in the retrospective study. Eleven patients were treated with beta-emitting 177Lu/90Y-DOTATOC, either intravenous (i.v.) (n = 5)
or intra-arterial (i.a.) (n = 6) and three patients received alpha-emitting 213Bi-DOTATOC (i.a.). CEUS and contrast-enhanced
CT (CE-CT) were performed before and 3 months after treatment. Results: CE-CT and CEUS presented comparable results in the
baseline study and in the assessment of perfusion changes due to the different treatment regimes. A therapy related decrease in tumor
perfusion is an early predictor of longterm morphologic response. Conclusion: CEUS is a cheap, ubiquitary available and radiation
free technique which showed comparable results for perfusion and diameter of liver metastases compared to CE-CT. Intensity
reduction in an arterial phase CEUS can be seen as a positive sign indicating long term tumor response to treatment. Therefore
CEUS may be considered as an imaging modality for monitoring early treatment after focal alpha and beta targeted therapy.JRC.E.5-Nuclear chemistr
Design and Vertical Tests of SPS-series Double-Quarter Wave (DQW) Cavity Prototypes for the HL-LHC Crab Cavity System
Crab crossing is essential for high-luminosity colliders. The High Luminosity
Large Hadron Collider (HL-LHC) will equip one of its Interaction Points (IP1)
with Double-Quarter Wave (DQW) crab cavities. A DQW cavity is a new generation
of deflecting RF cavities that stands out for its compactness and broad
frequency separation between fundamental and first high-order modes. The
deflecting kick is provided by its fundamental mode. Each HL-LHC DQW cavity
shall provide a nominal deflecting voltage of 3.4 MV, although up to 5.0 MV may
be required. A Proof-of-Principle (PoP) DQW cavity was limited by quench at 4.6
MV. This paper describes a new, highly optimized cavity, designated DQW
SPS-series, which satisfies dimensional, cryogenic, manufacturing and impedance
requirements for beam tests at SPS and operation in LHC. Two prototypes of this
DQW SPS-series were fabricated by US industry and cold tested after following
conventional SRF surface treatment. Both units outperformed the PoP cavity,
reaching a deflecting voltage of 5.3-5.9 MV. This voltage - the highest reached
by a DQW cavity - is well beyond the nominal voltage of 3.4 MV and may even
operate at the ultimate voltage of 5.0MVwith sufficient margin. This paper
covers fabrication, surface preparation and cryogenic RF test results and
implications
Contrast-enhanced ultrasound monitoring of perfusion changes in hepatic neuroendocrine metastases after systemic versus selective arterial ¹⁷⁷Lu/⁹⁰Y-DOTATOC and ²¹³Bi-DOTATOC radiopeptide therapy
Aim - radiopeptide therapy with beta emitter labeled ¹⁷⁷Lu/⁹⁰Y- DOTA(0)-Phe(1)-Tyr(3)-octreotide (DOTATOC) and more recently also alpha emitting ²¹³Bi-DOTATOC are promising new treatments for neuroendocrine tumors. No early predictors for treatment response have been recognized and tumor-shrinkage after radiation therapy appears slowly. In some solid tumors a decline in tumor perfusion was found predictive of final treatment response but the gold standard multiphase computed tomography (CT) has a high radiation burden. Therefore we evaluated the ability of contrast-enhanced ultrasound (CEUS) to evaluate tumor perfusion as a response criteria. 14 patients with hepatic neuroendocrine tumor (NET) metastases were enrolled in the retrospective study. Eleven patients were treated with beta-emitting ¹⁷⁷Lu/⁹⁰Y-DOTATOC, either intravenous (i.v.) (n = 5) or intra-arterial (i.a.) (n = 6) and three patients received alpha-emitting ²¹³Bi-DOTATOC (i.a.). CEUS and contrast-enhanced CT (CE-CT) were performed before and 3 months after treatment. CE-CT and CEUS presented comparable results in the baseline study and in the assessment of perfusion changes due to the different treatment regimes. A therapy related decrease in tumor perfusion is an early predictor of longterm morphologic response. Conclusion: CEUS is available and radiation free technique which showed comparable results for perfusion and diameter of liver metastases compared to CE-CT. Intensity reduction in an arterial phase CEUS can be seen as a positive sign indicating long term tumor response to treatment. Therefore CEUS may be considered as an imaging modality for monitoring early treatment after focal alpha and beta targeted therapy. Key Words: contrast-enhanced ultrasound, radionuclide therapy, treatment response, DOTATOC PET/CT
MRI of the lung (3/3)-current applications and future perspectives
BACKGROUND: MRI of the lung is recommended in a number of clinical indications. Having a non-radiation alternative is particularly attractive in children and young subjects, or pregnant women. METHODS: Provided there is sufficient expertise, magnetic resonance imaging (MRI) may be considered as the preferential modality in specific clinical conditions such as cystic fibrosis and acute pulmonary embolism, since additional functional information on respiratory mechanics and regional lung perfusion is provided. In other cases, such as tumours and pneumonia in children, lung MRI may be considered an alternative or adjunct to other modalities with at least similar diagnostic value. RESULTS: In interstitial lung disease, the clinical utility of MRI remains to be proven, but it could provide additional information that will be beneficial in research, or at some stage in clinical practice. Customised protocols for chest imaging combine fast breath-hold acquisitions from a "buffet" of sequences. Having introduced details of imaging protocols in previous articles, the aim of this manuscript is to discuss the advantages and limitations of lung MRI in current clinical practice. CONCLUSION: New developments and future perspectives such as motion-compensated imaging with self-navigated sequences or fast Fourier decomposition MRI for non-contrast enhanced ventilation- and perfusion-weighted imaging of the lung are discussed. Main Messages • MRI evolves as a third lung imaging modality, combining morphological and functional information. • It may be considered first choice in cystic fibrosis and pulmonary embolism of young and pregnant patients. • In other cases (tumours, pneumonia in children), it is an alternative or adjunct to X-ray and CT. • In interstitial lung disease, it serves for research, but the clinical value remains to be proven. • New users are advised to make themselves familiar with the particular advantages and limitations
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