Biomedical subjects
Publications and source records attributed to N Lazarov.
Benign cystic teratoma of the caecum of 24 year woman interpreted as an ovarian tumor. Rare case that can contribute to the gynecology theory, practice and diagnostic.
The authors describe a rare case of carcinoma of the cervix uteri with exophytic accretion, prominating through the vaginal introitus of a 52-year old patient. They make the conclusion that accurate, precise and early diagnostics is necessary as well as an experienced operative team because during surgery there might be surprises, disturbing its normal course and outcome.
A case of papilloferous serous cystadenoma of boundary malignancy in a 29-year old female patient, with VCS syndrome--status post phlebothrombosis ileofemoralis dextra. Thrombosis vena cava superior is presented.
Cedax is an oral third generation cephalosporin for use with a wide spectrum of antibacterial activity. It has been made a comparative study between Cedax and other third generation cephalosporins in 40 pregnant women with asymptomatic bacteriuria. The authors made a conclusion Cedax is a preferred antibacterial drug for treatment of similar infections of pregnancy because of his easy application way and the absence of side effects.
The striving of surgeon for achieving better long-term results of surgical treatment of patients with breast cancer put the searching of new independent prognostic factors for the exit of the treatment. This has become possible in the last decade of XX century when new diagnostic methods as immunochistochemistry, polimerase chain reaction (PCR), cytomorphology etc. entered the clinical practice. With bone marrow biopsy in patients with breast cancer earlier diagnosis of minimal residual disease is achieved, the approach to those patients is changed and a possibility for discovering women at higher risk is given. By immunochistochemistry method in the diagnostics of minimal residual disease in patients with breast cancer, more precise staging is achieved. This will change the therapeutic approach to these patients.
There is widespread acceptance that estrogen is involved in various steps of cellular differentiation during brain development. In the past years, we have demonstrated such a developmental role for estrogen in the rodent midbrain. Precisely, estrogen affects midbrain dopamine neurons with respect to functional and morphological maturation. On the cellular level, estrogen may act classically by binding and activating its respective nuclear receptors, thereby controlling the transcription of target genes. On the other hand, many estrogen effects in the CNS are transmitted nonclassically by interactions with putative membrane receptors and by stimulating distinct intracellular signaling cascades. In the midbrain, classical and nonclassical estrogen signaling routes operate side by side to ensure the proper development of dopaminergic cells. In the present report, we detail some of the cellular and molecular events which are activated by estrogen and are thought to take part in the estrogen-mediated stimulation of dopamine neuron differentiation.
In the present investigation the authors review 37 cases of peripartal hysterectomy, made in our clinic for a 10 year period. The results show that there is a high risk intervention, because of the massive blood loss and altered anatomical structure.
Searching of more effective methods for early diagnosis of Endometrial Cancer has confirmed the hysteroscopy as most complete and sufficient manner in this direction. In the present exposition the authors are sharing their experience and making some practical conclusions that may be useful for the physicians applying this method.
Skin distribution of substance P (SP)-, somatostatin (SOM)-, calcitonin gene-related peptide (CGRP)- and neuropeptide Y (NPY)-like immunoreactivity (LI) in vitiligo patients was studied by an indirect immunofluorescence technique. Immunocytochemical characteristics of the epidermis, dermal-epidermal junction, papillary and reticular dermis and skin appendages were analyzed in lesional and marginal vitiligo areas, as well as in healthy skin. In healthy pigmented skin, SP-, SOM-, CGRP-, and NPY-LI nerve fibers were observed with specific distributional patterns. In uninvolved vitiligo skin, thin SP-containing fibers were evident in dermal papillae, extending into the epidermis, and SP-LI fibers were seen around blood vessels and sweat glands. SOM-LI varicose nerve fibers were associated with Meissner corpuscles in the dermal papillae, while CGRP-LI was demonstrated in the free subepidermal nerve terminals and in sensory nerve fibers around blood vessels, hair follicles and sweat glands. Autonomic NPY-nerve fibers innervated the eccrine sweat glands and blood vessels. The distribution of these neuropeptides in both marginal and lesional areas of vitiliginous skin was the same as in the skin of healthy control subjects, except for an increased immunoreactivity against NPY and, to a lesser extent, against CGRP in the skin depigmentation lesions. The elevated NPY levels in skin affected by vitiligo suggest that this peptide may serve as a neurochemical marker in the pathogenesis of the disease, thus supporting the neuronal theory of vitiligo.
Skin distribution of substance P (SP)-, somatostatin (SOM)-, calcitonin-gene-related peptide (CGRP)- and neuropeptide-Y (NPY)-like immunoreactivity in vitiligo patients was studied by an indirect immunofluorescence technique. Immunocytochemical characteristics of the epidermis, dermoepidermal junction, papillary and reticular dermis, and skin appendages were analyzed in lesional and marginal vitiligo areas as well as in healthy skin. SP-, SOM-, CGRP-, and NPY-immunoreactive nerve fibers were observed in healthy pigmented skin, with patterns specific for immunoreactive distribution. Thin SP-containing fibers were observed in dermal papillae, extending into the epidermis, and SP-immunoreactive nerve fibers were seen around blood vessels and sweat glands. SOM-immunoreactive varicose nerve fibers were associated with Meissner's corpuscles in dermal papillae, while CGRP-like immunoreactivity was demonstrated in free subepidermal nerve terminals and sensory nerve fibers around blood vessels, hair follicles and sweat glands. Autonomic NPY-containing nerve fibers innervated eccrine sweat glands and blood vessels. The distribution of these neuropeptides was the same in healthy controls, except for an increased immunoreactivity to NPY and to a lesser extent to CGRP. These results suggest that NPY may serve as a neurochemical marker in the pathogenesis of the disease, thus supporting the neuronal theory of vitiligo.
A rare case of a large paraovarian cyst in an unusually young 18-age-old patient, filling up the whole abdominal cavity, is described. It is concluded that an accurate and precise diagnostics, and also an experienced surgical team would be required in such a surgery as complete surprises can take place effecting its course and outcome.
Several amino acids may function as neurotransmitters in the nervous system. The potential role of glutamate (Glu) and aspartate in excitatory responses was demonstrated and it was established that GABA and glycine act as inhibitory agents. The present study aimed at investigating the availability of Glu and GABA in certain feline sensory ganglia, i.e. the trigeminal (TrG), nodose and dorsal root ganglia (DRG). A significant part of the neurons were GABA-positive (19.5% to 23.5%). These were large-sized neurons as well as small- to medium-sized ones. The intensity of immunostaining varied from weak to strong. GABA-containing neuronal fibres were seen in the neuropil and some of them surrounded unstained ganglionic cells. The Glu-immunoreactive (IR) neuronal perikarya in all the investigated ganglia were 63.6% to 66.4%. The majority of positive cells were small- to medium-sized, but large primary sensory neurons were also seen. There was no difference between the intensity of the reaction in the primary sensory and small neurons. Glu-IR neuronal fibres were seen in close apposition to immunopositive as well as immunonegative neurons. In conclusion, in the TrG, nodose and DRG, GABA and glutamate are involved in neurotransmission. There is a significant number of GABAergic neurons in the investigated sensory ganglia of the cat. The difference in the expression of these amino acids suggests that they can act not only as neurotransmitters but also as modulators of sensory information.
Explore the source record for details and available documents.
The trigeminal ganglion (TrG) and mesencephalic trigeminal nucleus (MTN) neurons are involved in the transmission of orofacial sensory information. The presence of nitric oxide (NO), a putative neurotransmitter substance in the nervous system, was examined in the cat TrG and MTN using nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) histochemistry and nitric oxide synthase (NOS) immunohistochemistry. In the TrG, where the majority of the trigeminal primary afferent perikarya are located, most of the intensely NADPH-d/ NOS-stained cells were small in size and distributed randomly throughout the ganglion. The medium-sized neurons were moderately stained. A plexus of pericellular varicose arborizations around large unstained ganglion cells and densely stained fibers in-between could also be observed. In the caudal part of the MTN, both NADPH-d activity and NOS immunoreactivity was present in MTN neurons. In addition, a few scattered NADPH-d/NOS-containing neurons were found in the mesencephalic-pontine junction part of the nucleus. In contrast, only nerve fibers and their terminals were present at a more rostral level in the mid- and rostral MTN. MTN neuronal perikarya were enveloped in fine basket-like NADPH-d/ NOS-positive networks. Differential expression patterns of NOS and its marker NADPH-d suggest that trigeminal sensory information processing in the cat MTN is controlled by nitrergic input through different mechanisms. We introduce the concept that NO can act as a neurotransmitter in mediating nociceptive and proprioceptive information from periodontal mechanoreceptors but may also participate in modulating the activity of jaw-closing muscle afferent MTN neurons.
The rat mesencephalic trigeminal nucleus (MTN) receives a dopaminergic innervation. In order to identify and localize dopaminoceptive cells within this nucleus, expression of D1 and D2 dopamine (DA) receptors was examined by immunocytochemistry with subtype-specific antibodies and in situ hybridization with digoxigenin-labeled cRNA probes. Immunocytochemical labeling was restricted to neuronal perikarya and proximal processes whereas the hybridization signal was confined to MTN cell bodies. Cells immunopositive for D1 were located throughout the entire MTN whereas cells labeled with D2 antibodies were concentrated in its caudal portion. D1 receptor message was found in relatively low levels. In contrast, high levels of mRNA for D2 were seen in MTN neurons. The distribution of DA receptor mRNA-containing cells were very similar to those of DA receptor immunoreactivity. Neurons expressing the D1 receptor gene were localized in both rostral and caudal portions, which receive inputs from masticatory muscle spindles and from spindles and periodontal ligament receptors, respectively. D2 receptors were limited to ventrocaudally located cells. These results suggest that processing of proprioceptive information in the MTN is controlled by the DAergic input through different postsynaptic mechanisms.
Quantitative information about dopaminergic neuron numbers in the mesencephalon is needed to assess the significance of physiological cell death in the regulation of the development of this neural system. Therefore, stereological techniques were applied to determine absolute numbers of mesencephalic neurons immunoreactive to tyrosine hydroxylase during the ontogenetic period between embryonic day (E) 13 and postnatal day (P) 90. Male and female CBA/J mice were examined separately. The most rapid development with a 2.5-fold increase of total counts of immunostained cells per midbrain took place in the prenatal period. Beginning at E21, immunostained cells were counted separately in their three main locations, substantia nigra (SN), ventral tegmental area (VTA), and retrorubral field (RRF). Neuron numbers in RRF and VTA reached adult levels perinatally. In contrast, counts of immunostained cells in SN continued to increase postnatally. The only sign of cell loss was a transient decrease in VTA cell numbers (but not in total numbers of immunostained midbrain neurons) between E21 and P14. There were no statistically significant sex differences in cell numbers at any time point investigated. It is concluded that physiological cell death is not a major factor in the developmental regulation of dopaminergic cell numbers in the mouse midbrain.
The ultrastructure and synaptic organization of the mesencephalic trigeminal nucleus (MTN) were studied in adult cats by transmission electron microscopy and more precisely quantified with an automated image analysis system. Two subpopulations of MTN neurons were identified within the nucleus: large spherical or ovoid (pseudo)unipolar cells amounted to about 60% of the total population that resemble typical primary sensory neurons and small multipolar neurons (estimated 40%), some of which are possibly interneurons. By electron microscopy, most neurons in the MTN proved to have a rich cytoplasm in the perikaryon with abundant rough endoplasmic reticulum, a large number of free ribosomes and polysomes, also well-developed Golgi complex, and numerous mitochondria and neurofilaments indicating a high rate of protein synthesis and axonal transport in these cells. Three types of synaptic contacts were observed in the MTN: axodendritic, axosomatic and axospinic of both symmetric and asymmetric morphology. Most of them (almost 90%) were axodendritic and axodendritic spine. Approximately 70% of axon terminals contained small round vesicles (S-type boutons) whereas the other 30% belonged to the P-type boutons filled with a pleomorphic vesicle population. Axosomatic synapses were comparatively rare accounting for 10% of the total. About two-third of them were of S-type and almost 25% of the remaining third were F-type in which flat synaptic vesicles could be seen, and less than 10% were P- and G-types with granular vesicles.
The distribution of calcitonin gene-related peptide (CGRP)- and neuropeptide Y (NPY)-like immunoreactivity (LI) in the cat trigeminal ganglion (TrG) and mesencephalic trigeminal nucleus (MTN) was studied by the indirect immunofluorescent technique and unlabelled peroxidase-antiperoxidase method. A positive reaction for both CGRP and NPY was found only in the TrG primary afferent neurons. Between 40% and 50% of the perikarya displayed CGRP-LI whereas few of the trigeminal principal neurons (approximately 1%) showed NPY-LI. Most of the CGRP-immunoreactive cells were small to medium-sized (20-40 microns in diameter) and were distributed throughout the ganglion. NPY appeared specifically in medium-sized to large-sized trigeminal neurons (up to 60 microns). CGRP and NPY also occurred in varicose nerve fibres running among the cell bodies and in pericellular baskets around a small number of large unstained ganglion cells. In contrast, CGRP- and NPY-LI were present only in the nerve fibres and terminals of the cat MTN. The immunoreactive varicosities travelled towards the negative MTN neurons and formed basket-like arborizations around their cell bodies. Synaptic contact between the immunolabelled axonal profiles and perikarya of trigeminal primary afferent neurons could not be seen in the TrG and MTN of the cat. The results provide further evidence for the interrelation between sensory and autonomic systems.