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J Spacek

Publications and source records attributed to J Spacek.

At least 37 records · Page 2Linked to original sources

[Importance of clinical prognostic factors in the treatment of ovarian carcinoma].

OBJECTIVE: To present a review of clinical prognostic factors in ovarian cancer. SUBJECT: Review. SETTING: Department of Obstetrics and Gynaecology, Medical Faculty Hradec Králové, Charles University, Prague; Department of Clinical Oncology, Medical Faculty Hradec Králové, Charles University, Prague; Bristol-Myers Squibb, Department of Oncology, Prague. SUBJECT AND METHOD: Discussion about current evidence from literature. CONCLUSION: Epithelial ovarian cancers are characterized by a broad spectrum of biological behavior ranging from tumors that have an excellent prognosis and high likelihood of cure to those that progress rapidly and have a very poor prognosis. This wide clinical spectrum is partly reflected by a number of clinical prognostic variables. The most important of these clinical factors is stage, volume of residual tumor remaining after surgical resection, performance status and age, interval between end of primary therapy and beginning of recurrence, drug resistance.

Adult↗

[Histopathologic prognostic factors, serum markers and selected molecular biologic factors in ovarian carcinoma].

OBJECTIVE: A review of histopathological prognostic factors, serum markers and selected molecular biological factors in ovarian cancer. DESIGN: Review. SETTING: Department of Obstetrics and Gynaecology, Medical Faculty Hradec Králové, Charles University, Prague; Department of Biological and Medical sciences, Pharmaceutical Faculty, Hradec Králové, Charles University, Prague; Department of Clinical Oncology, Medical Faculty Hradec Králové, Charles University, Prague; Bristol-Myers Squibb, Department of Oncology, Prague. METHOD: Discussion about current evidence from literature. CONCLUSION: Except clinical prognostic factors the wide spectrum behaviour of epithelial ovarian cancers is reflected by some histopathological prognostic factors, serum markers and some molecular biological factors. The most important are grade and tumor ploidy, the level of CA 125 and its changes during the treatment, mutations of p53, BRCA 1 and 2.

Biomarkers, Tumor↗

The changes of biological markers and treatment efficacy in schizophrenia.

1. In a group of schizophrenic patients, the effect and selected parameters of biological markers were evaluated during the index hospitalisation in the acute phase of schizophrenia (n = 30) and then after one year of ambulatory treatment. 2. During the acute treatment, a significant drop in symptomatology was recorded in average; an analogical tendency was observed further on, too. Apart from that, a significant change was observed in 5/41 parameters being monitored (the pair t-test): I) decrease in the total NES score, II) decrease in the sensorial integration subscale NES score, III) increase in psychomotor speed, IV) decrease in auditory reaction time, V) increase in basal cortisol. 3. In the comparison of the successfully (severity of illness after one year = 1, 2) and unsuccessfully (severity of illness after one year > or =3) treated patients in the beginning of treatment in the acute phase, the unsuccessful group had a significantly higher score of negative symptomatology, and by the end of the acute treatment, again, a significantly higher score of negative symptomatology, a higher total PANSS score and a greater severity of illness. 4. In the acute phase, the successful group had a significantly better score in individual items of the Contemporary Memory Scale and a significantly worse performance and goal-aimed concentration in the Bourdon test than the unsuccessfully treated one; apart from that, it had a significantly higher cortisol level after dexamethasone, which was also reflected in the lower percentage rate of dexamethasone nonsupression. 5. In the course of the year, a drop in the total NES score for the individual subscales occurred; a significant drop was observed in the sensory integration subscale. The worse concentration items improved significantly in the successful group in contrast to the unsuccessful group, where they showed a downgrade tendency. Changes in Contemporary Memory Scale were negligible and mostly below statistical significance. Apart from that, a drop in basal cortisolemia occurred in the successful group and an increase in cortisolemia after administering dexamethasone was registered in the unsuccessful group. 6. The more successful group had a significantly lower NES score, a significantly better visual reaction time and a smaller forgetting item (in percentiles) after the one-year period.

Acute Disease↗

[Fetal rhabdomyoma of the mucosa of the lip (case report)].

In a 15-year-old male the foetal type of rhabdomyoma was diagnosed in the mucosa of the lower lip. Diagnosis of this relatively rare tumour prevents possible mistaking for a malignant process and an inadequate therapeutic procedure.

Adolescent↗

[Evaluation of the results of surgery of intracranial supratentorial tumors in 363 children over the past 50 years (1948-1997)].

At the Department of Neurosurgery, Hradec Králové, in the course of 50 years (1948-1997) 363 children, 199 boys and 164 girls (1.2:1) aged under 18 years were operated on for intracranial supratentorial tumours. The average age in children at the time of first operation was 9.3 years; most frequently they participated those of 8 and 11 to 14 years of age. Children aged 1, 2 and 3 years constituted 4.7%, 4.4% and 5% of operations. The tumours were located in: cerebral hemispheres 123 (33.8%), lateral ventricles 17 (4.7%), IIIrd ventricle 5 (1.4%), hypothalamus 26 (7.2%), thalamus 19 (5.2%), basal ganglia 24 (6.6%), sellar region 86 (23.7%), chiasmatic region 38 (10.5%) and pineal region 19 (5.2%). 223 of tumours (61.4%) were located in the midline and 140 of them (38.6%) laterally (in hemispheres and lateral ventricles of the brain). 268 of tumours were histologically verified (73.8%) and 95 of cases were evaluated according to the neurosurgeon's point of view and/or to the clinical and CT controls (26.2%), because of the biopsy (especially in the pre-CT era) was highly riskfull. Histological typing of tumours was retrospectively reevaluated according to the present WHO classification. Summarized 53 types of tumours were differentiated. The most frequent lesions were various variants of astrocytic gliomas (135 = 37.2%). Further on the craniopharyngiomas dominated (73 = 20.1%). The tumours were operated on through craniotomies 299 times, by primarily drainage operations 52 times, functions 6 times, stereotactically 8 times and or by combination of these operations 82 times. Reoperation was needed for postoperative complications in 1.7% (6 times) and for delayed recurrence in 11.3% (41 times). The postoperative mortality (up to 1 month after initial surgery) was in 156 children operated on in pre-CT era (between 1948 and 1977), as compared with 207 children operated on in the era of CT (between 1978 and 1997) in astrocytomas 3.8:0%, pilocytic astrocytomas 6.5:2.8%, craniopharyngiomas 15.4:0% and in all tumours 12.2:2.9%. 16 children with orbital tumours (the average age 5.8 years) operated on with orbitofrontal approach were also evaluated. 14 of them survive for 5-37 years (on the average 16.6 years). The chronological development of diagnostic and operative processes of supratentorial tumours in children's care is discussed. The prognostic elements of present histobiological classification of tumours are positively evaluated.

Adolescent↗

Three-dimensional organization of cell adhesion junctions at synapses and dendritic spines in area CA1 of the rat hippocampus.

Recent work has emphasized the role of adhesion molecules in synaptic plasticity, including long-term potentiation in the hippocampus. Such adhesion molecules are concentrated in junctions that are characterized by dense thickenings on both sides of the junction and are called puncta adhaerentia (PA). Reconstruction from serial electron microscopy was used to determine the location and size of PA in the stratum radiatum of hippocampal area CA1, where many of the previous functional studies have been performed. PAs were found at the edges of synapses on 33% of dendritic spines. The areas occupied by PA were variable across different types of synapses, occupying 0.010+/-0.005 microm2 at macular synapses and 0.034+/-0.031 microm2 at perforated synapses. Another zone, called a vesicle-free transition zone (VFTZ), was identified. Like the PA, this zone also had no presynaptic vesicles and was located at the edges of synapses; however, unlike the PA, the presynaptic thickening was less than the postsynaptic thickening. Together, 45% of spine synapses had PA and/or VFTZ occupying 23+/-11% of the total junctional area between axons and spines. PA also occurred at nonsynaptic sites involving neuronal as well as glial elements. Most (64%) of these PAs occurred between nonsynaptic portions of dendritic spines and neighboring astrocytic processes. Smooth endoplasmic reticulum was often apposed to one or both sides of the synaptic and the nonsynaptic PA. These findings provide further data as a structural basis for understanding the roles of cell adhesion junctions in hippocampal synaptic function and plasticity.

Animals↗

Posterior cranial fossa surgery in 454 children. Comparison of results obtained in pre-CT and CT era and after various types of management of dura mater.

At the Department of Neurosurgery, Hradec Kralové, 454 children (aged under 18 years) were operated on for posterior cranial fossa lesions in a period of 49 years (1948-1996). The majority (402) had tumours: cerebellar astrocytomas 149 (37.1%), medulloblastomas 139 (34.6%), brain stem gliomas 46 (11.4%), ependymomas 28 (7.0%), and others 40 (9.9%). Postoperative mortality was compared for the pre-CT era (1948-1977) and the CT era (1978-1996): astrocytomas (8.6%:4.7%), medulloblastomas (14.9%:2.9%), brain stem gliomas (21.7%:19.0%), ependymomas (18.2%:6.3%), and others (40.0%:7.4%). The initially high mortality was due to insufficient intracranial decompression, brain oedema and disturbances of cerebrospinal fluid circulation. Obstructive hydrocephalus was treated in 53 children with tumours and 25 with aqueduct stenoses, by Torkildsen's drainage in 5.5%, and/or by catheterisation of aqueduct in 12.3%. The main postoperative complications of medial posterior fossa surgery in 429 children operated on were: pseudomeningocele (12.3%), active hydrocephalus (6.2%) and CSF leakage (4.6%). Only 8.2% had shunts placed for these complications. We presume that this low percentage of shunts used results from a frequent use of duraplasties and drains installed at the primary operation. The dura mater was initially (1948-1954) left open (50 cases), and later (1955-1958) also sutured (37 cases), and from 1958, onward, and especially from 1961, reconstructed by a medial approach by means of various grafts (377 cases). In all, duraplasty was performed in 81.6% of cases. The grafts used for dura mater reconstruction were prepared from autogeneic (1.6%), allogeneic (72.3%), xenogeneic (24.8%), or synthetic (1.3%) material. They were successful in 99.2% of cases (all materials). Our own suture technique for posterior fossa duraplasty is presented.

Adolescent↗

Choroid plexus cyst of the left lateral ventricle with intermittent blockage of the foramen of Monro, and initial invagination into the III ventricle in a child.

A cyst of the choroid plexus of the left lateral ventricle with intermittent blockage of the foramen of Monro and initially with invagination of the III ventricle in a child is described. In a 6-week-old boy a ventriculoatrial shunt was implanted for correction of an active asymmetrical hydrocephalus of unknown origin. When he was 3 months of age a water-soluble contrast CT ventriculography revealed a noncolloid cyst localised predominantly in the upper portion of the III ventricle. At that time the ventricular catheter obstructed with choroid plexus was removed; new bilateral catheters in a parieto-occipital region were implanted. In the course of the next 4 years, first the atrial catheter had to be extracted and then the peritoneal catheter was changed, in both cases because of obstruction. Periods of normal life alternated with periods of transient and intermittent symptoms of increased intracranial pressure, papilloedema, and myoclonic jerks. Repeated computed tomography (CT) and magnetic resonance imaging (MRI) showed stabilised hydrocephalus with an enlarged left lateral ventricle. When the boy was 16 years old MRI revealed a choroid plexus cyst in the left lateral ventricle 2 cm in diameter, with a ballvalve type of obstruction of the foramen of Monro. CT stereoendoscopic resection of the wall of a large cyst filled with cerebrospinal fluid was performed, and two additional adnexal small cysts were coagulated using the bipolar coagulator, Diomed 25 laser and scissors; the symptoms then regressed, except for superior bilateral altitudinal anopsia. Light and electron microscopy of the cyst wall is reported. The cyst was composed of collagenic connective tissue lined with a basal lamina lacking in epithelial cells. The preoperative and postoperative MRI are presented. Choroid plexus cysts localised in the anterior part of lateral ventricles are very rare, and all reported cases have been in male patients. According to the literature our case is only the third ever described in a child.

Brain Diseases↗

[Practical remarks on publishing in international scientific journals].

Differences in style of publishing in national and international scientific journals could negatively influence the acceptance of a manuscript. The article directs an attention of beginning authors to possible pitfalls and tries to give them advice how to reduce elementary mistakes and to enhance a chance for the acceptance of the manuscript.

Periodicals as Topic↗

[Synovial metaplasia around breast implants].

Three cases of the periprosthetic breast capsules showing typical features of synovial metaplasia are presented. The histological picture is characterized by the presence of cellular layer mimicking synovial membrane. These elements are devoid of basement membrane, otherwise, nevertheless, they strongly resemble single- or multilayered epithelium. Focally, the differentiation towards giant multinucleated cells is noted. Immunohistochemical profile, as well as the ultrastructure of the cells, confirms their histiocytic origin with advanced differentiation towards elements of the synovial membrane. These histological features are referred to as synovial or synovial-like metaplasia. They are found in considerable fraction of textured breast implant capsules. The pathogenesis remains uncertain; however, similar picture was observed in other locations in association with prolonged or repeated action of mechanical forces. Thus, movement of the implant in situ is the most probable trigger of synovial metaplasia.

Adult↗

[Pseudoangiomatous hyperplasia of mammary stroma].

Four cases of pseudoangiomatous hyperplasia of mammary stroma (PAH) were described (3 women and 1 man aged 15 to 42 years). Clinically in women, they presented as firm, nontender, movable nodules, 1 to 4 cm in diameter, diagnosed clinically usually as fibroadenoma. In the male patient, the lesion was tender, resembling gynecomastia. Microscopically, they were characterized by the presence of anastomosing, empty-looking, slit-shaped spaces irregularly lined by the spindle cells with small, uniformly ovoid nuclei, dispersed throughout the mammary stroma. Immunohistochemically, these cells were vimentin positive, factor VIII and CD31 negative. They did not express estrogen receptor, in one case there was a weak progesteron receptor positivity. Ultrastructurally, the lining cells were of a fibroblastic character. The pathogenesis of PAH is unclear, presumed to be of reactive nature by the authors, probably as an exuberant reaction of stromal cells to hormonal stimuli. In differential diagnosis, PAH should be distinguished from low-grade angiosarcoma, as well as from perilobular hemangioma, diffuse angiomatosis and vascular anomalies.

Adolescent↗

Three-dimensional organization of smooth endoplasmic reticulum in hippocampal CA1 dendrites and dendritic spines of the immature and mature rat.

Recent studies have shown high levels of calcium in activated dendritic spines, where the smooth endoplasmic reticulum (SER) is likely to be important for regulating calcium. Here, the dimensions and organization of the SER in hippocampal spines and dendrites were measured through serial electron microscopy and three-dimensional analysis. SER of some form was found in 58% of the immature spines and in 48% of the adult spines. Less than 50% of the small spines at either age contained SER, suggesting that other mechanisms, such as cytoplasmic buffers, regulate ion fluxes within their small volumes. In contrast, >80% of the large mushroom spines of the adult had a spine apparatus, an organelle containing stacks of SER and dense-staining plates. Reconstructed SER occupied 0.001-0.022 microm3, which was only 2-3.5% of the total spine volume; however, the convoluted SER membranes had surface areas of 0.12-2.19 microm2, which were 12 to 40% of the spine surface area. Coated vesicles and multivesicular bodies occurred in some spines, suggesting local endocytotic activity. Smooth vesicles and tubules of SER were found in continuity with the spine plasma membrane and margins of the postsynaptic density (PSD), respectively, suggesting a role for the SER in the addition and recycling of spine membranes and synapses. The amount of SER in the parent dendrites was proportional to the number of spines and synapses originating along their lengths. These measurements support the hypothesis that the SER regulates the ionic and structural milieu of some, but not all, hippocampal dendritic spines.

Aging↗

Detailed evaluation of 2959 allogeneic and xenogeneic dense connective tissue grafts (fascia lata, pericardium, and dura mater) used in the course of 20 years for duraplasty in neurosurgery.

Surgical experience with 2959 allogeneic and xenogeneic dense connective tissue grafts (1767 of fascia lata, 909 of pericardium, and 283 of dura mater), used in 2665 neurosurgical operations performed in the course of 20 years (1976 to 1995) is reported. Duraplasty using either allogeneic or xenogeneic grafts has had a similar, and favourable clinical outcome. Nevertheless, the pliable deep frozen fascia lata grafts, which could be used in any location, have been reserved for sella turcica plugging, anterior cranial base plasty, aneurysmal wrapping, and surgery of lipomyelomeningocele. Pericardium and dura mater grafts were in the majority of cases used over the brain convexity and posterior cranial fossa. Ovine pericardium proved to be superior to bovine and allogeneic pericardia because of its workability, flexibility, reduced thickness, and better transparency. Postsurgical complications occurred in 7.3%, and they were: 1) cerebrospinal fluid fistulas in 2.8%; 2) meningites in 2.3% (aseptic 1.4%, bacterial 0.8%, and tumoural 0.1% meningites); 3) pseudomeningoceles in 2.2%; 4) wound infections in 0.6%; 5) malresorptive hydrocephalus in 0.5%; and 6) adhesions to nerve tissue in 0.5%. The majority of complications healed without surgery. Forty-eight grafts (1.6%) failed to fulfil the requirements of the surgeon, and 46 of them were re-operated upon. Though another thirty-nine grafts healed successfully, 39 shunts (1.5%) had to be performed for malresorptive hydrocephalus (0.9%), and/or for a big pseudomeningocele (0.6%). So, the pure complication rate in 2665 duraplasties was 3.1%. The complex evaluation of the allogeneic and xenogeneic grafts (fascia, pericardium, and dura mater), used for duraplasty in neurosurgery during the last 20 years proved them, as remarkably good, with a success rates of 96.9%.

Adult↗

Filamentous contacts: the ultrastructure and three-dimensional organization of specialized non-synaptic interneuronal appositions in thalamic relay nuclei.

Filamentous contacts are non-synaptic interneuronal junctions characteristic of thalamic relay nuclei. Symmetrical filamentous contacts occur between two dendrites, two somata or a dendrite and a soma; asymmetrical filamentous contacts occur between axon terminals and dendrites, or occasionally somata, chiefly between the large specific afferent axon terminals of the synaptic glomeruli and the shafts of relay cell dendrites. Both are arranged as extensive net-like (reticular) specializations. The strands of the network enclose fenestrae of variable shape and size and, in perpendicular thin sections, appear as stretches of slightly widened intercellular space containing an electron-dense material and bounded by plasma membranes, the cytoplasmic surfaces of which are coated by electron-dense material into which microfilaments appear to insert. The lamina of cytoplasmic material in dendrites and somata is thicker than that in axon terminals and contains distinct electron-dense sub-units. Regular synaptic junctions may be situated like islands within the territory of an asymmetrical filamentous contact, and small spot-like close membrane appositions resembling gap junctions are occasionally seen in the fenestrae adjacent to the strands of both varieties of contact. Bundles of neurofilaments running in different directions, but in a plane parallel to the plasma membrane, are prominent on either side of the symmetrical filamentous contact and on the dendritic side of the asymmetrical variety. The agranular reticulum also exhibits differences between the contact types. Because of their highly specialized ultrastructure and specific distribution, filamentous contacts probably do not serve a purely adhesive function. Their possible role in the establishment and maintenance of orderly connections between cells is discussed but not favoured. Filamentous contacts probably mediate some form of intercellular communication, possibly involving gap junctions.

Intercellular Junctions↗