Impedance spectroscopy and biosensing

This chapter introduces the basic terms of impedance and the technique of impedance measurements. Furthermore, an overview of the application of this transduction method for analytical purposes will be given. Examples for combination with enzymes, antibodies, DNA but also for the analysis of living cells will be described. Special attention is devoted to the different electrode design and amplification schemes developed for sensitivity enhancement. Finally, the last two sections will show examples from the label-free determination of DNA and the sensorial detection of autoantibodies involved in celiac disease.

Impedance spectroscopy and biosensing

This chapter introduces the basic terms of impedance and the technique of impedance measurements. Furthermore, an overview of the application of this transduction method for analytical purposes will be given. Examples for combination with enzymes, antibodies, DNA but also for the analysis of living cells will be described. Special attention is devoted to the different electrode design and amplification schemes developed for sensitivity enhancement. Finally, the last two sections will show examples from the label-free determination of DNA and the sensorial detection of autoantibodies involved in celiac disease.

Changing aspects of psychiatric inpatient treatment. A census investigation in five European countries

This paper presents data obtained in a one-day census investigation in five European countries (Austria, Hungary, Romania, Slovakia, Slovenia). The census forms were filled in for 4191 psychiatric inpatients. Concerning legal status, 11.2% were hospitalised against their will (committed) and 21.4% were treated in a ward with locked doors. There was only a small correlation between commitment and treatment in a locked ward. More frequent than treatment of committed patients in locked wards was treatment of committed patients in open wards (Austria, Hungary) and treatment of voluntary patients in closed wards (Slovakia, Slovenia). Concerning employment, 27.7% of patients aged 18-60 held a job before admission. The vast majority of patients (84.8%) had a length of stay of less than 3 months. A comparison of these data with the results of a study performed in 1996 and using the same method shows a decrease of rates of long-stay patients. In 1996 the rates of employment were significantly higher in Romania (39.3%) and Slovakia (42.5%) compared to Austria (30.7%). These differences disappeared in 1999 due to decreasing rates of employment in Romania and Slovakia. The numbers of mental health personnel varies between types of institution (university or non-university) and countries, being highest in Austria and lowest in Romania. A considerable increase in the numbers of staff was found in Slovakia.

Experimental cauda equina compression induces HSP70 synthesis in dog

The heat shock protein 70 (HSP70) is a key component of the stress response induced by various noxious conditions such as heat, oxygen stress, trauma and infection. In present study we have assessed the consequences of the compression of lower lumbar and sacral nerve roots caused by a multiple cauda equina constrictions (MCEC) on HSP70 immunoreactivity (HSP70-IR) in the dog. Our data indicate that constriction of central processes evokes HSP70 up-regulation in the spinal cord (L7, S1-Co3) as well as in the corresponding dorsal root ganglion cells (DRGs) (L7-S1) two days following injury. A limited number of bipolar or triangular HSP-IR neurons were found in the lateral collateral pathway (LCP) as well as in the pericentral region (lamina X) of the spinal cord. In contrast, a high number of HSP70 exhibiting motoneurons with fine processes appeared in the ventral horn (laminae VIII-IX) of lumbosacral segments. Concomitantly, close to them a few lightly HSP70-positive neuronal somata or cell bodies lacking the HSP70-IR occurred. In the DRGs, HSP70 expression was mildly up-regulated in small and medium-sized neurons and in satellite cells. On the contrary, DRGs from intact or sham-operated dogs did not reveal HSP70 specific neuronal staining. In conclusion, we have demonstrated that the MCEC in dogs mimicking the cauda equina syndrome in clinical settings evokes expression of HSP70 synthesis in specific neurons of the lumbo-sacro-coccygeal spinal cord segments and in small and medium sized neurons of corresponding DRGs. This suggests that HSP70 may play an active role in neuroprotective processes partly by maintaining intracellular protein integrity and preventing the neuronal degeneration in this experimental paradigm.

Experimental cauda equina compression induces HSP70 synthesis in dog

The heat shock protein 70 (HSP70) is a key component of the stress response induced by various noxious conditions such as heat, oxygen stress, trauma and infection. In present study we have assessed the consequences of the compression of lower lumbar and sacral nerve roots caused by a multiple cauda equina constrictions (MCEC) on HSP70 immunoreactivity (HSP70-IR) in the dog. Our data indicate that constriction of central processes evokes HSP70 up-regulation in the spinal cord (L7, S1-Co3) as well as in the corresponding dorsal root ganglion cells (DRGs) (L7-S1) two days following injury. A limited number of bipolar or triangular HSP-IR neurons were found in the lateral collateral pathway (LCP) as well as in the pericentral region (lamina X) of the spinal cord. In contrast, a high number of HSP70 exhibiting motoneurons with fine processes appeared in the ventral horn (laminae VIII-IX) of lumbosacral segments. Concomitantly, close to them a few lightly HSP70-positive neuronal somata or cell bodies lacking the HSP70-IR occurred. In the DRGs, HSP70 expression was mildly up-regulated in small and medium-sized neurons and in satellite cells. On the contrary, DRGs from intact or sham-operated dogs did not reveal HSP70 specific neuronal staining. In conclusion, we have demonstrated that the MCEC in dogs mimicking the cauda equina syndrome in clinical settings evokes expression of HSP70 synthesis in specific neurons of the lumbo-sacro-coccygeal spinal cord segments and in small and medium sized neurons of corresponding DRGs. This suggests that HSP70 may play an active role in neuroprotective processes partly by maintaining intracellular protein integrity and preventing the neuronal degeneration in this experimental paradigm.

Cauda equina syndrome and nitric oxide synthase immunoreactivity in the spinal cord of the dog

The development of the cauda equina syndrome in the dog and the involvement of spinal nitric oxide synthase immunoreactivity (NOS-IR) and catalytic nitric oxide synthase (cNOS) activity were studied in a pain model caused by multiple cauda equina constrictions. Increased NOS-IR was found two days post-constriction in neurons of the deep dorsal horn and in large, mostly bipolar neurons located in the internal basal nucleus of Cajal seen along the medial border of the dorsal horn. Concomitantly, NOS-IR was detected in small neurons close to the medioventral border of the ventral horn. High NOS-IR appeared in a dense sacral vascular body close to the Lissauer tract in S1-S3 segments. Somatic and fiber-like NOS-IR appeared at five days post-constriction in the Lissauer tract and in the lateral and medial collateral pathways arising from the Lissauer tract. Both pathways were accompanied by a dense punctate NOS immunopositive staining. Simultaneously, the internal basal nucleus of Cajal and neuropil of this nucleus exhibited high NOS-IR. A significant decrease in the number of small NOS immunoreactive somata was noted in laminae I-II of L6-S2 segments at five days post-constriction while, at the same time, the number of NOS immunoreactive neurons located in laminae VIII and IX was significantly increased. Moreover, high immunopositivity in the sacral vascular body persisted along with a highly expressed NOS-IR staining of vessels supplying the dorsal sacral gray commissure and dorsal horn in S1-S3 segments. cNOS activity, based on a radioassay of compartmentalized gray and white matter regions of lower lumbar segments and non-compartmentalized gray and white matter of S1-S3 segments, proved to be highly variable for both post-constriction periods.

Cauda equina syndrome

Single or double-level compression of the lumbosacral nerve roots located in the dural sac results in a polyradicular symptomatology clinically diagnosed as cauda equina syndrome. The cauda equina nerve roots provide the sensory and motor innervation of most of the lower extremities, the pelvic floor and the sphincters. Therefore, in a fully developed cauda equina syndrome, multiple signs of sensory disorders may appear. These disorders include low-back pain, saddle anesthesia, bilateral sciatica, then motor weakness of the lower extremities or chronic paraplegia and, bladder dysfunction. Multiple etiologies can cause the cauda equina syndrome. Among them, non-neoplastic compressive etiologies such as herniated lumbosacral discs and spinal stenosis and spinal neoplasms play a significant role in the development of the cauda equina syndrome. Non-compressive etiologies of the cauda equina syndrome include ischemic insults, inflammatory conditions, spinal arachnoiditis and other infectious etiologies. The use of canine, porcine and rat models mimicking the cauda equina syndrome enabled discovery of the effects of the compression on nerve root neural and vascular anatomy, the impairment of impulse propagation and the changes of the neurotransmitters in the spinal cord after compression of cauda equina. The involvement of intrinsic spinal cord neurons in the compression-induced cauda equina syndrome includes anterograde, retrograde and transneuronal degeneration in the lumbosacral segments. Prominent changes of NADPH diaphorase exhibiting, Fos-like immunoreactive and heat shock protein HSP72 were detected in the lumbosacral segments in a short-and long-lasting compression of the cauda equina in the dog. Developments in the diagnosis and treatment of patients with back pain, sciatica and with a herniated lumbar disc are mentioned, including many treatment options available.

Fos protein expression in sacral spinal cord in relation to early phase of cauda equina syndrome in dogs

1. The aim of the present study is to map the incipient phase of Fos expression in the sacral spinal cord neuronal pools of multiple cauda equina constrictions canine model. 2. Fos-positive neurons were found bilaterally in the lateral portion of superficial dorsal horn layers (Laminae I-III) and along the lateral edge of the dorsal horn accompanied by the lateral collateral pathway, fibers of Lissauer's tract, terminating at the sacral parasympathetic nucleus. Similarly, high Fos expression was detected in the ventral portion of the dorsal sacral commissure and in the dorsomedial portion of the anterior horns at S1-S3 segment level. Finally, a clearly expressed Fos-positivity was disclosed bilaterally in the neuropil of the nucleus Y in the anterior horn. 3. Data from the present study show that continuous stimulation of the central fibers of sacral dorsal root ganglia neurons, i.e., fibers of sacral primary afferents, unlike those using various stimulations of the peripheral fibres offers an unusual pattern of Fos-like immunoreactivity.

Effect of midthoracic spinal cord constriction on catalytic nitric oxide synthase activity in the white matter columns of rabbit

The distribution and changes of catalytic nitric oxid synthase (cNOS) activity in the dorsal, lateral and ventral white matter columns at midthoracic level of the rabbit's spinal cord were studied in a model of surgically-induced spinal cord constriction performed at Th7 segment level and compared with the occurrence of nicotinamide adenine dinucleotide phosphate diaphorase expressing and neuronal nitric oxide synthase immunoreactive axons in the white matter of the control thoracic segments. Segmental and white-column dependent differences of cNOS activity were found in the dorsal (141.5 +/- 4.2 dpm/microm protein), lateral (87.3 +/- 11.5 dpm/microm protein) and ventral (117.1 +/- 7.6 dpm/microm protein) white matter columns in the Th5-Th6 segments and in the dorsal (103.3 +/- 15.5 dpm/microm protein), lateral (54.9 +/- 4.9 dpm/microm protein), and ventral (86.1 +/- 6.8 dpm/microm protein) white matter columns in the Th8-Th9 segments. A surgically-induced constriction of Th7 segment caused a disproportionate response of cNOS activity in the rostrally (Th5-Th6) and caudally (Th8-Th9) located segments in both lateral and ventral white matter columns. While a statistically significant decrease of cNOS activity was detected above the constriction site in the ventral columns, a considerable, statistically significant increase of cNOS activity was noted in the white lateral columns below the site of constriction. It is reasoned that the changes of cNOS activity may have adverse effects on nitric oxide (NO) production in the white matter close to the site of constriction injury, thus broadening the scope of the secondary mechanisms that play a role in neuronal trauma.

[Injuries of the intracranial part of the carotid artery]

The objective of the submitted work was to draw attention to different types of injuries of the intracranial portion of the carotid artery and some problems associated with its solution. The investigated group comprised 7 subjects (2 women, 5 men) aged 19 to 76 years who attended between Jan. 1, 1995 and Feb. 29 2000 the Neurosurgical Clinic in Kosice with sequelae of injuries of the intracranial carotid artery. Two patients developed a pseudoaneurysm. In one case it was manifested by subarachnoid haemorrhage on the 24th day after a crash, in one instance by diplopia six weeks after a retrobulbar injection. Injury of the intracavernous portion of the artery was manifested in one instance by profuse epistaxis on the 17th day after a fall from a bicycle, four times by the development of a carotid-cavernous fistula several days to 3 years after the head injury. In the diagnosis classical as well as MR and digital subtraction angiography were used. In the patient with epistaxis classical carotid angiography was 3 times negative. The results are comparable with data in the literature. In three patients the problem was resolved by ligature of the common carotid artery on the neck. In another three it was necessary to use extra-intracranial trapping. One patient will be subjected to endovascular surgery. Two patients died (a 76-year-old woman from bronchopneumonia, a 19-year-old man from meningitis, despite a liquor fistula treated correctly by a patch).

Incipient cauda equina syndrome as a model of somatovisceral pain in dogs: spinal cord structures involved as revealed by the expression of c-fos and NADPH diaphorase activity

Segmental and laminar distribution of Fos-like immunoreactive, reduced nicotinamide adenine dinucleotide phosphate diaphorase (NADPHd)-exhibiting and double-labeled (Fos-like immunoreactive and NADPHd-exhibiting) neurons was examined in lower lumbar and sacral segments of the dog spinal cord using the model of multiple cauda equina constrictions. NADPHd histochemistry was used as marker of nitric oxide synthase-containing neurons. The appearance and the time-course of Fos-like immunoreactive, NADPHd and double-labeled neurons was studied at 2 h and 8 h postconstriction characterized as the incipient phase of cauda equina syndrome. The occurrence of Fos-like immunoreactive and NADPHd-exhibiting neurons in fully developed cauda equina syndrome was studied at five days postconstriction. An increase in Fos-like immunoreactivity in superficial laminae (I-II) and an enhanced NADPHd staining of lamina VIII neurons were found. A statistically significant increase in Fos-like immunoreactive neurons was found in laminae I-II and VIII-X 8 h postconstriction, and in contrast, a prominent decrease in Fos-like immunoreactive neurons was found in laminae I-II, accompanied by a statistically significant increase in Fos-like immunoreactive neurons in more ventrally located laminae VII-X at five days postconstriction. Quantitative analysis of laminar distribution of constriction-induced NADPHd-exhibiting neurons revealed a considerable increase in these neurons in laminae VIII-IX 8 h postconstriction and a statistically highly significant increase in NADPHd-exhibiting neurons in laminae VII-X five days postconstriction. Concurrently, the number of NADPHd-exhibiting neurons in laminae I-II was greatly reduced. While a low number of double-labeled neurons was found throughout the gray matter of lower lumbar and sacral segments at 2 h postconstriction, a statistically significant number of double-labeled neurons was found in lamina X 8 h and in laminae VII-X five days postconstriction. The course and distribution of anterograde degeneration resulting five days after multiple cauda equina constrictions are compared with segmental and laminar distribution of Fos-like immunoreactive and NADPHd-exhibiting neurons. Prominent involvement of the spinal cord neurons appearing in the lumbosacral segments at the early beginning and in fully developed cauda equina syndrome results in a Fos-like immunoreactivity and strongly enhanced NADPHd staining of some neuronal pools. Under such circumstances, an early cauda equina decompression surgery is advisable aimed at decreasing or preventing the derangement of the neural circuits in the lumbosacral segments.

[Functional cardiovascular disorders in patients with neuroses at rest and during physical loading]

The authors examined using selected non-invasive cardiological examination methods 33 patients with neurosis. Four were eliminated on account of organic heart disease. From the group of 29 patients 12 had ECG changes (41%)--of those 5 (17%) had an incomplete right bundle branch block and 1 (3%) had a left anterior fascicular block; 2 (7%) had the syndrome of early repolarization and 4 (14%) had changes of the T wave. The polycardiogram did not reveal a statistically significant difference in the investigated indicators (PEPc, LVETc, WI, PVR) between the group of sick and healthy patients at rest. Ambulatory 24-hour monitoring of the ECG was done in 21 patients--in 2 (10%) it revealed a sinoatrial block, in 10 (50%) episodic sinus tachycardia, in 6 (30%) occasional supraventricular extrasystoles, in 5 (25%) rare ventricular extrasystoles. The echocardiographic examination confirmed the statistically significantly increased systolic function of the left ventricle (P less than 0.05) in all investigated parameters (%D, Vcf, MNSER, EF), as compared with healthy subjects. After a loading ECG test of 28 patients 2 (7%) had ST-T changes. Statistical comparison with the group of healthy subjects revealed in the patients with neurosis a significantly reduced value of systolic (P less than 0.005) and median blood pressure (P less than 0.01), as well as of the inner cardiac work at the peak of the submaximum load (P less than 0.05) and an increase of the diastolic blood pressure (P less than 0.05) during the 10th minute of recovery. The orthostatic test in 20 patients with neurosis revealed a significantly higher heart rate at rest and during the 30th and 60th second after rising (P less than 0.05) and a significantly lower orthostatic index (P less than 0.001) on statistical comparison with healthy subjects.

Plasma cortisol and prolactin response to insulin-induced hypoglycemia in neurosis

Prolactin (PRL) and plasma cortisol response to insulin induced hypoglycemia were studied in 14 patients with various somatic and vegetative complaints of neurotic character and in 12 controls. In all examined subjects glucose level fell below 50% of basal values and below 2.2 mmol/l. Significant PRL and plasma cortisol response were present in all controls. Plasma cortisol increase in control group was at least 1.5 fold higher than basal values and the difference between basal concentrations and highest values after stimulation was at least 0.25 mumol. Individual peak of PRL values in group of controls was 1.8-10 fold greater than basal levels. In the group of 14 patients in 11 cases no PRL response to challenge was found and in 4 cases also plasma cortisol response was blunted. In two patients extremely exaggerated PRL reaction was found. Different PRL responses to insulin-induced hypoglycemia are probably a manifestation of different types of neurotransmitter metabolism breakdown.

[Psychoreactive disorders: clinical description of pathologic reactions, pathologic reactive states and reactive psychoses]

After the introduction to the problem presented in the first part, the author submits a description of clinical units. The aim is to provide documentation of his concept and to unify the understanding of these conditions into a uniform system; conditions which, although adequately described, are included among different disorders and their classification and description is not uniform. The need of this description is urgent not only because the new generation of psychiatrists does not know the original classification but also because knowledge of these conditions has expended and this calls for new evaluation and description.

[Psychoreactive disorders: introduction to the problem and comments on its diagnosis and classification]

The author submits an introduction to the problem of psychoreactive disorders and some comments on the concept, diagnosis and classification of these disorders which at first sight are very simple but actually are rather complicated. Their knowledge is so far very inadequate despite their large number. The author hopes that the present work will stimulate further concentrated elaboration of this urgent psychiatric problem.

[Etiopathogenesis and diagnosis of psychoreactive disorders]

Some remarks are made on the conception, etiopathogenesis, and diagnostics of psychoreactive disturbances. It is supposed that besides stress also other dynamisms and mechanisms of the personality are involved in their development. The first author introduces for own diagnostic purposes a three-dimensional classification, which contains the following items: 1. the situation and its importance, 2. the subject's profile, and 3. the means used and the kind of the subject's activity inclusive of the pathologic reactions.