Angiogenesis in pituitary adenomas and the normal pituitary gland

Angiogenesis is essential for tumor growth beyond a few millimeters in diameter, and the intratumoral microvessel count that represents a measure of angiogenesis has been correlated with tumor behavior in a variety of different tumor types. To date no systematic study has assessed pituitary tumors of different secretory types, correlating vascular count with tumor size. The vascular densities of pituitary tumors and normal anterior pituitary were therefore assessed by counting vessels labeled using the vascular markers CD31 and ulex europaeus agglutinin I. One hundred and twelve surgically removed pituitary adenomas (30 GH-secreting, 25 prolactinomas, 15 ACTH-secreting, and 42 nonfunctioning tumors) were compared with 13 specimens of normal anterior pituitary gland. The vascular counts in the normal anterior pituitary gland were significantly higher (P < 0.05) than those in the tumors using both CD31 and ulex europaeus agglutinin I. In addition, microprolactinomas were significantly less vascular (P < 0.05) than macroprolactinomas, although there was no such difference between vascular densities of microadenomas and macroadenomas producing GH. ACTH-secreting tumors were, like microprolactinomas, of much lower vascular density than the normal pituitary and other secreting and nonsecreting tumor types. In marked contrast to other tumors, pituitary adenomas are less vascular than the normal pituitary gland, suggesting that there may be inhibitors of angiogenesis that play an important role in the behavior of these tumors.

Diagnosing dementia: interrater reliability assessment and accuracy of the NINCDS/ADRDA criteria versus CERAD histopathological criteria for Alzheimer's disease

We investigated the interrater reliability and accuracy of two independent medical doctors in using NINCDS/ADRDA criteria to classify 82 elderly subjects enrolled in OPTIMA, a longitudinal study investigating dementia. Kappa statistics revealed moderate agreement (0.5) in overall classification of dementia type, and almost perfect agreement (0.9) on the absence or presence of dementia. Combining NINCDS/ADRDA 'possible' and 'probable' Alzheimer's disease (AD) categories produced substantial agreement (0.7). Comparison with CERAD histopathological criteria for AD showed that combining 'possible' and 'probable' AD resulted in a high sensitivity and accuracy, but a low specificity. To increase specificity, the NINCDS/ADRDA 'probable AD' category should be used alone. An important finding was that the accuracy of diagnoses of AD made from the case notes alone was not different from the diagnoses obtained following active involvement with participants.

Analysis of the genetic variability of the 1st (CCC/ACC, P52T) and the 10th exons (bp 1012-1704) of the TSH receptor gene in Graves' disease

We determined the genetic variability of the 1st (CCC/ACC, P52T polymorphic variant) and 10th exons (bp 1012-1704) of the TSH receptor (TSHR) gene in Graves' disease. A total of 101 Graves' patients and 163 control subjects were screened. The A253 mutant allele was carried by nine patients with Graves' disease (8.91%) and 13 control subjects (7.98%) in heterozygous genotype. No significant difference in the frequency of the mutant allele was found between Graves' patients and control subjects. These results provide evidence that the A253 polymorphism has no genetic relevance in Graves' disease. Moreover, the DNA nucleotide sequence of 693 bp of the 10th exon (bp 1012-1704) of the TSHR gene was determined in 15 Graves' patients. Six patients were homozygous for the wild-type allele and nine were heterozygous for the mutant allele at the 253rd nucleotide of the first exon. No polymorphism was found in the DNA sequences obtained from leukocytes of Graves' patients, similarly to the sequences obtained from the nine control subjects. None of the nine patients carrying the A253 polymorphism in the 1st exon of the TSHR had polymorphism in the examined part of the 10th exon, including two additional patients whose thyroid tissue was directly analysed. In all likelihood, the polymorphisms of the examined regions of either the 1st or the 10th exon of the THSR gene do not contribute to the genetic susceptibility to Graves' disease.

[Reduced utilization of antibiotics in Swedish hospitals. Considerable variations between hospitals concerning choice and use of preparations]

Defined daily dose (DDD) consumption of antibiotics in 26 Swedish hospitals decreased by an average of 25% from 1990 to 1998, according to statistics from Apoteket AB. In one hospital, the decrease was 61%. Average consumption of tetracyclines and penicillins, expressed as percentage of total antibiotics consumption, decreased by 5% and 7% respectively, while quinolones and cephalosporins increased by 4% and 7% respectively. Consumption of tetracyclines and quinolones varied between individual hospitals by a factor of four.

Scalp distribution of the dimensional complexity of the EEG and the P3 ERP component in stroke patients

The use of recently developed techniques allows the quantitative investigation of the non-linear properties of the electrical activity of the brain not only in basic but also in applied research. The point correlation dimension (PD2) was used in this study for the analysis of the electroencephalogram (EEG) recorded in patients with unilateral stroke caused by middle cerebral artery occlusion. The scalp distribution of the PD2 and that of the P3 event-related potential component was mapped and frequency spectra were calculated. Compared to normal controls, asymmetrical PD2 distribution was observed with low values on the side of the stroke, the extension of which depended on recording conditions (level of vigilance) and only partially corresponded to the region characterized by slow frequencies. In one case, ipsilateral reduction of the P3 wave was caused by a small subcortical stroke. The efficacy of the linear and non-linear methods in localizing brain pathology are evaluated and compared.

Cerebrovascular disease and threshold for dementia in the early stages of Alzheimer's disease

Cerebrovascular disease and Alzheimer's disease commonly occur together in the elderly and each may contribute to dementia. Here we present evidence that cerebrovascular disease significantly worsens cognitive performance in the earliest stages of Alzheimer's disease.

Leiden mutation in patients with Crohn’s disease

BACKGROUND

Inherited resistance to activated protein C is a common risk factor of venous thrombosis. In a majority of patients the defect is caused by single-point mutation in the gene for factor V. This mutated form of factor Va is more stable against proteolytic attack by activated protein C. The prevalence of this inherited defect in the European population is at least 5%. The risk of thrombosis is increased in the case of heterozygosity 5- to 10-fold, in homozygous subjects 50- to 100-fold, but even homozygous individuals will not necessarily suffer from thrombosis. The aim of our study was to determine whether the presence of Leiden mutation might play a role in the pathophysiology and clinical manifestation of Crohn's disease.

MATERIALS AND METHODS

Thirty-four patients with Crohn's disease (mean age 34 years, range 21-72 years) were studied. None of them had a history of thrombotic episodes. We examined the case history for risk factors: use of oral contraceptive, steroids, cigarette smoking. Levels of fibrinogen, APTT, lupus anticoagulant and levels of IgG and IgM class anticardiolipin (ACL) antibodies were determined. The Leiden mutation was detected by PCR method (Denninger et al., 1995).

RESULTS

Fibrinogen was elevated in five cases, lupus anticoagulant in one case, but none of the patients had ACL antibodies in the serum. Molecular analyses showed heterozygosity for the Leiden factor V gene mutation in the case of 30 patients (25%).

CONCLUSION

Thromboembolic events frequently complicate the clinical course of patients with Crohn's disease; however, we do not have enough knowledge about its role in manifestation of the disease. These results suggested the high frequency of Leiden mutation among our patients and suggest a new genetic background of Crohn's disease.

Cell cycle-related protein expression in vascular dementia and Alzheimer's disease

Recent findings from our and other laboratories indicate that cell cycle-related phenomena may play a key role in the formation of Alzheimer-type pathology and neuronal cell death in both Alzheimer's and cerebro-vascular diseases. In this study we examine the expression patterns of cyclins A, B1, D1 and E in neuronal nuclei in the hippocampus in autopsied healthy elderly individuals, Alzheimer's disease patients and subjects suffering from cerebrovascular disease with and without co-existing Alzheimer's disease. Nuclear cyclin B1 and cyclin E expression was detected in hippocampal neurones in each subject category. However, cyclin B1 expression was significantly elevated in the CA1 of patients suffering from cerebro-vascular disease alone, while cyclin E expression was significantly higher in the CA4 subfield in patients suffering from mixed Alzheimer's and cerebro-vascular diseases compared to subjects in other categories. We hypothesize that cell cycle re-entry may occur in healthy elderly people leading to age-related cell death and mild Alzheimer-type pathology in the hippocampus. However, in pathological conditions, the cell cycle arrest may lead either to the development of severe Alzheimer-related pathology or to excess apoptotic cell death as in vascular dementia.

The enhanced peroxidase one step method increases sensitivity for detection of Ki-67 in pituitary tumours

AIM

To compare the Ki-67 labelling index determined using the enhanced peroxidase one step (EPOS) method with that using the standard ABC technique in pituitary tumours.

METHODS

Adjacent sections were immunostained using the EPOS and ABC techniques with the same Ki-67 antibody and same antigen retrieval method.

RESULTS

The labelling index measurements with the EPOS Ki-67 antibody were significantly higher than when using the traditional ABC method, and there was a positive correlation between the two techniques when performed on the same cases. This suggests that a higher proportion of cells are within the cell cycle than previously thought, although it gives no direct information on the rate of proliferation of the tumour.

CONCLUSIONS

It appears that the EPOS system is not only more convenient but may be more sensitive than traditional techniques for detecting Ki-67 in the nuclei of cells, thus demonstrating more accurately which cells have entered the cell cycle.

Quantitative trait loci for blood pressure exist near the IGF-1, the Liddle syndrome, the angiotensin II-receptor gene and the renin loci in man

Blood pressure (BP) is heritable and finding quantitative trait loci that influence BP is an important step in identifying genes responsible for BP regulation. Sixty-six pairs of dizygotic (DZ) twin subjects and their parents were used in a sib-pair analysis to look for linkage of selected candidate genes to the quantitative trait BP. Microsatellite markers were tested in the vicinity of the gene loci for insulin-like growth factor-1 (IGF-1), Liddle syndrome, autosomal-dominant hypertension with brachydactyly, angiotensinogen, angiotensin II type 1 receptor, angiotensin-converting enzyme, renin, and lipoprotein lipase. BP was measured in a standardized manner. Heart size was determined echocardiographically. Significant linkage was found at the IGF-1, Liddle syndrome, and AT1 receptor gene for systolic BP. Linkage for diastolic BP was found at the autosomal-dominant hypertension with brachydactyly locus. Both systolic and diastolic BP were linked to the renin gene locus. The linkage was most consistent for the IGF-1 gene locus and systolic BP. Linkage was also found between the IGF-1 gene locus and posterior cardiac wall thickness, septal thickness, and left ventricular mass index. It is suggested that these quantitative trait loci may be important for the subsequent detection of allelic variants for elevated BP. Furthermore, these results linking the IGF-1 gene locus to both BP and cardiac dimensions underscore the importance of the IGF-1 gene as a candidate gene for cardiovascular disease.

A 3-year randomized trial of ropinirole and bromocriptine in early Parkinson's disease. The 053 Study Group

OBJECTIVE

To compare the long-term efficacy and safety of ropinirole with bromocriptine over 3 years in patients with early PD with limited or no previous dopaminergic therapy.

METHODS

In this prospective, double-blind, parallel-group study, 335 patients were randomized to 0.75 mg ropinirole or 1.25 mg bromocriptine titrated upward at weekly intervals--maximum permitted daily doses were 24 mg ropinirole, 40 mg bromocriptine.

RESULTS

Approximately one third of patients in each group withdrew prematurely, mostly because of adverse experiences; 61/102 (60%) of ropinirole-treated and 59/112 (53%) of bromocriptine-treated patients completed the study on the dopamine agonist alone. Mean doses for all patients at completion were 12 mg (SD 6) ropinirole and 24 mg (SD 8) bromocriptine. Occurrence of adverse experiences in both groups was similar. Emergence of dyskinesias was low. Both treatments induced marked improvements in Unified Parkinson's Disease Rating Scale activities of daily living (ADL, Part II) and motor (Part III) scores over the first 12 weeks, which were maintained during the study. After 3 years, patients in the ropinirole group had a mean improvement in motor score of 31% compared with 22% in the bromocriptine group (p = 0.086) and a significantly better ADL score (treatment difference 1.46 points, p = 0.009) [corrected].

CONCLUSIONS

Both dopamine agonists are effective in the early treatment of a high proportion of PD patients; effectiveness persists for at least 3 years. Those who completed the study had a significantly better functional status on ropinirole than on bromocriptine.

Impaired vasoreactivity of the basilar artery system in patients with brainstem lacunar infarcts

BACKGROUND AND PURPOSE

Diminished vasoreactivity (VR) has been evidenced in patients with hemispheric small vessel disease, however, there is no data regarding vertebrobasilar (VB) territory VR changes in patients with subcortical vascular encephalopathy located in the brainstem. Therefore, we compared the cerebral blood flow velocity (CBFV) responses of the VB system during different vasoregulatory challenges in healthy volunteers to those in patients with brainstem lacunar infarcts.

METHODS

In 20 patients with brainstem lacunar infarcts and in 10 healthy volunteers the VR of the VB system was measured by analyzing the CBFV changes during different stimulation paradigms (ventilation, tilting and acetazolamide tests). During transcranial Doppler registration the systemic blood pressure and the expiratory partial CO2 pressure were monitored.

RESULTS

During hypercapnia the VR was significantly higher in the control group than in the patient group (10.1 +/- 4.9 vs. 3.4 +/- 5.0 cm/s/kPa, p = 0.0025). In a subgroup of patients with mean baseline CBFV <25 cm/s the VR was 1.5 +/- 2.4 cm/ s/kPa, while patients with mean baseline CBFV >25 cm/s showed a significantly higher value (7.8 +/- 6.9 cm/s/kPa). Furthermore, in patients with mean baseline CBFV <25 cm/s the pulsatility index was significantly higher than in patients with mean baseline CBFV >25 cm/s (1.11 +/- 0.26 vs. 0.86 +/- 0.19, p = 0.0325), reflecting significantly higher vascular resistance in the former group. Although CBFV measurements during tilting and acetazolamide tests tended to support these findings, they showed no significant differences between patients and controls.

CONCLUSION

Patients with cerebral microangiopathy involving the brainstem showed impaired VR in the VB flow territory in association with baseline CBFV.

Ultrastructural localization of Hsp-72 examined with a new polyclonal antibody raised against the truncated variable domain of the heat shock protein

In spite of the intensive search for the determination of the continuously widening physiological and pathological roles of different stress proteins, their ultrastructural localization at the electron microscopic (EM) level has hardly been examined. As it becomes increasingly evident that the function and physiological effectiveness of stress proteins are highly dependent on their spatial location and their associations with diverse regulator proteins, the demand for morphological studies which can identify their detailed distribution within the cells is evident. The reason for the practical lack of studies carried out at the EM level, lies in the shortage of reagents with suitable specificity and avidity necessary for this type of examination. To create such a reagent, a polyclonal antibody was raised using a recombinant truncated form of the inducible Hsp-72 protein. The antibody was extensively characterized, using different immunochemical methods to determine and verify its specificity, and then it was tried in ultrastructural examinations. Using the new antibody, it was possible to analyze the intracellular distribution of Hsp-72 with the immunogold technique. The localization of Hsp-72 was demonstrated directly at the ultrastructural level in the cytoplasm (especially at the cisterns of the RER), in the nucleus (mainly around the heterochromatic regions) and at both sides of the nuclear envelope close to the membrane pores. Apart from these localizations, Hsp-72 was found in several membrane bordered intracellular structures, which mainly belong to the endosomal-lysosomal system. We provide the first morphological verification of the appearance of Hsp-72 on the surface of the cells. Also novel is the indication, that the stress protein may recycle from the cell surface using a common route which includes coated pits and the endosomal system.

[Risk factors in various groups of stroke patients (Analysis of 500 cases of the Budapest Stroke Database)]

Risk factor profile of 500 consecutive acute++ stroke cases in the protocol of the Budapest Stroke Data Bank has been analysed. High frequency of risk factors and additive occurrence have been documented when compared with other stroke registries; hypertension 75%, hypercholesterolemia 68%, ischemic heart disease 61%, hypertriglycerolemia 39%, smoking 38%, serious hypercholesterolemia 36%, diabetes mellitus 30%, peripheral artery disease 10%, elevated hematocrit 7% and elevated number of platelets 7%. More than one risk factors have been registered in 85% of the patients. Three risk factors at the same patient have been found in 28%. The highest number of risk factors is seven at the same patient. The stroke subtypes have been characterized with "cluster-like" association of risk factors. In the hemorrhagic group (9.4% of all cases) hypertension and alcoholism are the main factors; in the atherosclerotic group (49.4%) more male, smoking peripheral artery disease and hypercholesterolemia have been registered; in the lacunar stroke group (27%) high frequency of hypertension, smoking, diabetes mellitus, hypercholesterolemia and hypertriglycerolemia have been found and in the cardiogenic embolia group (10.6%) more female, higher age, ischemic heart disease and atrial fibrillation are the recurrent risk factors. There is no difference between the risk factor profile++ registered in the left versus right hemispheral strokes, in the anterior versus posterior strokes and in the first ever or recurrent strokes.

Mitochondrial enzyme expression in the hippocampus in relation to Alzheimer-type pathology

Recent reports have suggested that mitochondrial dysfunction may contribute to the progression of the pathology of Alzheimer's disease (AD). However, both increases and decreases in the activity of cytochrome oxidase have been described in the hippocampi of AD patients. In this study we used immunohistochemistry and quantitative autoradiographic methods to study the expression pattern of two cytochrome oxidase subunit proteins (nuclear-encoded COX IV and mitochondrial-encoded COX I) in the hippocampus in relation to the development of AD-type pathology. We found heterogeneous expression of both COX subunits in AD with an increased expression of both subunit proteins in healthy, non-tangle-bearing, neurones but absence of both subunit proteins in tangle-bearing neurones. Levels of COX IV but not of COX I were related to the amount of hyperphosphorylated tau accumulated in the same hippocampal region but not to the amount of amyloid deposited in sporadic AD. In Down's syndrome COX I and COX IV were similarly increased in the presence of AD pathology in non-tangle-bearing neurones. However, in these cases levels of enzyme expression were correlated to the amount of amyloid accumulation but not the amount of hyperphosphorylated tau in the hippocampus. We believe that heterogeneity of expression of mitochondrial enzyme proteins between neurones may contribute to the conflicting conclusions in previous reports regarding relative levels of cytochrome oxidase activity in the hippocampus in AD. We hypothesise that the increased mitochondrial enzyme expression in healthy-appearing neurones of AD brains may represent a physiological response to increased functional demand on surviving neurones as a consequence of AD-related neuronal pathology.

Elevated serum TNF-alpha level as a link between endothelial dysfunction and insulin resistance in normotensive obese patients

AIMS

The aim of the study was to analyse the role of tumour necrosis factor-alpha (TNF-alpha) in insulin resistance and endothelial dysfunction in patients with different types of obesity.

PATIENTS AND METHODS

Fasting serum TNF-alpha immunoreactive concentration (enzyme-linked immunosorbent assay, ELISA) and bioactivity (L929 cell cytotoxicity assay), endothelin-1 and C-peptide levels (radioimmunoassay, RIA) were measured in 15 patients with android- and 13 patients with gynoid-type obesity and 15 lean healthy controls with normal glucose tolerance and blood pressure.

RESULTS

Significantly (P<0.01) higher TNF-alpha concentration (8.92 +/- 0.44 pg/ml) and bioactivity (3.12 +/- 0.48 U/ml) were found in patients with android obesity as compared to patients with gynoid obesity (7.01 +/- 0.30 pg/ml, 0.97 +/- 0.11 U/ml) and to the lean controls (6.88 +/- 0.26 pg/ml, 0.88 +/- 0.08 U/ml). Serum endothelin-1 (5.38 +/- 0.30 pg/ml) and C-peptide levels (4.82 +/- 0.71 ng/ml) were also significantly higher (P < 0.01) in patients with android-type obesity than in controls (3.89 +/- 0.43 pg/ml, 1.46 +/- 0.25 ng/ml, respectively). In patients with gynoid-type obesity, only the C-peptide levels proved to be significantly higher (2.84 +/- 0.29 ng/ ml). Endothelin-1 levels, although were found to be slightly higher, did not differ statistically from in controls (4.56 +/- 0.31 pg/ml). There were significant positive linear correlations only in patients with android-type obesity between TNF-alpha, body mass index (BMI), serum endothelin-1 and C-peptide levels.

CONCLUSIONS

TNF-alpha may be one of the factors contributing to insulin resistance and vascular dysfunction in patients with android obesity.

Suppressive effect of pentoxifylline on natural killer cell activity; experimental and clinical studies

The methylxanthine derivative pentoxifylline, widely used in the treatment of vascular diseases, also has numerous immunological effects. In in vitro experiments, the human natural killer cell cytotoxicity was investigated in the presence of pentoxifylline. A clinical trial involved an investigation of the natural killer cell activity in patients to whom pentoxifylline had been administered for different periods. The natural cytotoxicity in macroangiopathic patients treated with pentoxifylline was compared with that in healthy controls and that in patients with vascular diseases who did not receive pentoxifylline therapy. A total of 62 macroangiopathic patients and 20 healthy controls were investigated. The natural killer cell activity in patients receiving pentoxifylline therapy for more than a year proved to be significantly lower (P<0.005). The presence of vascular disease did not influence the natural killer activity. In the in vitro cytotoxicity reaction, pentoxifylline at a concentration of 100 microg/ml was found to suppress the natural killer cell cytotoxicity at any stage of the reaction. The influence of pentoxifylline on the natural killer cell activity was not due to inhibition of the expression of intercellular adhesion molecule-1. However, this drug significantly decreases (P<0.05) the apoptosis of target cells. It is presumed that the suppressor effect of pentoxifylline on natural killer cell activity should be taken into consideration in the treatment of clinical diseases where this drug is administered chronically.

The progression of Alzheimer's disease from limbic regions to the neocortex: clinical, radiological and pathological relationships

Alzheimer's disease (AD) is characterised by the gradual accumulation of neurofibrillary pathology in selected regions of the brain. Earlier studies indicate that the accumulation of neurofibrillary tangles is associated both with decline in patient's cognitive performance as well as with medial temporal lobe atrophy on CT scans. There are also indications that progression through the pathological stages of AD is associated with decline in cognitive functions. The results of this study indicate that progression of disease, especially beyond the boundaries of the limbic regions, is associated with marked decline in the cognitive performance of patients suffering from AD. However the clinical manifestations of early pathological stages are not so well defined. We also found that the atrophy of the medial temporal lobe on CT scans is related to the progression of pathology. Atrophy is most apparent when the disease reaches its isocortical stages and is not marked in the limbic stages of the disease. The additive effect of pathologies co-existing with AD is apparent in reduced cognitive scores, while the atrophy of limbic structures, as measured on CT scans, seems to be mainly attributable to AD-related pathology.

Relationship between clinical and radiological diagnostic criteria for Alzheimer's disease and the extent of neuropathology as reflected by 'stages': a prospective study

The distribution of pathology related to Alzheimer's disease (AD) is not uniform throughout the brain. Sites which have a predilection for the development of Alzheimer-type pathology are the limbic regions and neocortical association areas. The changes in these areas of the brain develop gradually, following a well-determined sequence that allows a pathological staging of the disease process. According to the staging hypothesis, the first pathological alterations develop in the transentorhinal and entorhinal regions. The neurofibrillary pathology then spreads into the hippocampus, but not until the final stages does it affect the neocortex. In this study we analyse the relationship between the pathological stages of AD, according ot the staging hypothesis, and the clinical diagnosis in a prospectively assessed patient group. Prediction of any given pathological stage from the clinical diagnosis was found to be poor. This may be partly due to the fact that additional pathologies can alter the clinical picture and severity of dementia in patients who are only in the initial stages of AD. Nevertheless, the NINCDS-ADRDA clinical criteria had a high sensitivity for detection of AD-related pathology: the 'probable AD' category included 22/38 (57.9%) of those in the late isocortical stage, while the 'possible AD' category included 19/23 (82.6%) of those in the limbic stage. Using proposed neuro-imaging protocols for improved identification of patients with AD-related pathology, we largely identified subjects in whom the extent of pathology had spread to the neocortex.

[Surgical treatment of mitral insufficiency using annuloplasty suture technic]

In 1991 a simple and cheap technique was introduced for mitral valve repair at our department. After repairing the mitral leaflets, where indicated a posterior leaflet annuloplasty was performed with a semicircular suture and the annulus fixed for the appropriate size by tying the stitch. Between July 1991 and December 1995 86 patients underwent the above procedure (average age 56.8 +/- 10.4 years). 45 patients had primary mitral valve disease (myxomatous degeneration, rheumatoid disease, endocarditis), the other 41 had functional mitral regurgitation secondary to severe aortic valve or coronary artery disease. Echocardiography showed severe mitral regurgitation in 77% of the patients. In 45 cases the mitral valve itself was also repaired (valvotomy, quadrangular resection, wedge resection, etc.) in 29 cases the aortic valve was replaced as well, while 24 patients required additional revascularisation of the myocardium. The 30 day mortality was 3.5%. One week after surgery echocardiography was performed at all patients and showed acceptable mitral valve area (2.28 +/- 0.39 cm2). In 28 cases mild mitral regurgitation was found, the other valves were competent. All but 3 patients were followed up (96.4%). There were 6 late deaths (3 cardiac, 2 non cardiac, 1 embolic, 7.2% late mortality). During the follow up period (31.7 +/- 11.2 months) 5 patients required mitral valve replacement for severe recurrent mitral regurgitation (6.0%). In two cases new chorda rupture caused the recurrence, in an other case the suture had torn out of the annulus due to inadequate surgical technique. In the last two cases the annulus had dilated with intact Prolene annuloplasty stitch present, 86.8% of the survivors were in NYHA class I. or II. Our results suggest that mitral valve repair in selected cases can be performed without using expensive annuloplasty rings. The suture used for annuloplasty should be strong, non absorbable and non stretchable. Since 1994, when we started using GoreTex suture instead of Prolene no more patients required reoperation for annuloplasty failure.

Mechanisms of neuronal death in Down's syndrome

There is growing evidence that neuronal death in Down's syndrome is due to apoptotic mechanisms. The phenomena, however, that trigger and regulate programmed cell death in the Down's syndrome-related neurodegeneration are still much debated. In vitro evidence has suggested that the main factor responsible for neuronal death in this condition is the accumulation of beta-amyloid, due to the overexpression of its precursor protein. Another hypothesis argues for the importance of reactive oxygen species in neuronal death. However, the in vivo findings do not entirely support either theories. We propose that neuronal apoptosis, as well as the formation of Alzheimer-type pathology, in Down's syndrome is due to an aberrant re-entry of neurones into the cell division cycle. Due to the simultaneous overexpression of conflicting cell cycle regulatory signals the mitogenic amyloid precursor and the differentiation factor S100, the cell cycle is abandoned. Subsequently the cell cycle arrest may lead to either the formation of Alzheimer-related pathology or to apoptotic cell death.

Expression of membrane-bound and soluble cell adhesion molecules by human brain microvessel endothelial cells

Expression of membrane-bound (mb) and soluble (s) forms of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) induced by tumor necrosis factor-alpha (TNF-alpha) has been measured by enzyme-linked immunosorbent assay in cultured human brain microvessel endothelial cells. Both the mb and the s forms of VCAM-1 and ICAM-1 were upregulated by TNF-alpha; however, the stimulation of the s forms was delayed in time. When piracetam, a neuroprotective drug, was added to the tissue culture medium simultaneously with TNF-alpha, the expression of mbVCAM-1 and ICAM-1 was lowered. Differential upregulation of mb and s forms of adhesion molecules and a novel effect of piracetam have been demonstrated in human brain microvessel endothelial cell cultures.

The cell division cycle and the pathophysiology of Alzheimer's disease

Evidence is growing of a role of apoptosis in neurodegenerative disorders including Alzheimer's disease. Recent research indicates that cell cycle disturbances may promote apoptosis in neurodegenerative diseases. In this commentary we will discuss the control of the cell cycle in mammalian cells in general and in the central nervous system in particular. We then summarize the evidence for cell cycle perturbations in Alzheimer's disease and discuss the possible significance these may have for the development of pathological changes in this disease. Our working hypothesis is that, contrary to previous belief, neurons in the adult human brain are capable of re-entering the cell division cycle. The progression of the cell cycle is normally arrested at an early stage and neurons are able to re-differentiate. However, in Alzheimer's disease the cell cycle is allowed to progress into the G2 phase. At this stage re-differentiation is not possible and the neurons will suffer one of two fates: either they will die via an apoptotic pathway or they may produce Alzheimer-type pathology.

Beneficial effect of octreotide treatment in acute pancreatitis in rats

CONCLUSIONS

Octreotide treatment contributes to the regulation of tumor necrosis factor (TNF) production in sodium taurocholate-induced acute necrotizing pancreatitis in rats. Owing to its complex effect, octreotide can partially ameliorate the deleterious consequences of acute necrotizing pancreatitis. Elevated TNF and interleukin-6 (IL-6) levels in the peritoneal fluid may be considered a consequence of the activation of peritoneal macrophages.

BACKGROUND

The effects of octreotide on exocrine pancreatic function have been investigated in numerous studies, but little attention has been paid to its influence on cytokine production in acute pancreatitis.

METHODS

Acute pancreatitis was induced by the retrograde injection of taurocholic acid into the pancreatic duct in male Wistar rats. Serum amylase activity, wet pancreatic weight/body weight (pw/bw) ratio, and TNF and IL-6 levels were measured. Four micrograms/kg of octreotide was administered subcutaneously at the time of induction of pancreatitis and 24 or 48 h later. Rats were sacrificed 6, 24, 48, or 72 h after the operation.

RESULTS

The serum amylase level and pancreatic weight to body weight ratio were decreased significantly in the octreotide-treated group. The serum TNF level was decreased significantly in the octreotide-treated group as compared with the control group at 6, 24, and 48 h (0.6 +/- 1.5, 2.0 +/- 3.3, and 0 vs 50 +/- 15.5, 37.5 +/- 18.4, and 13.1 +/- 12.5 U/mL, respectively). The ascites TNF level was decreased to 0 in the octreotide-treated group and was elevated in the control group at 72 h (28.0 +/- 49.0 U/mL). IL-6 production in ascites was extremely high in both groups at 6 h (80,000 +/- 43,817 pg/mL and 58,500 +/- 33,335 pg/mL), but the difference was not significant.

[In vitro and clinical effect of pentoxifylline on natural killer cell activity]

Pentoxifylline used in the treatment of vascular diseases has also some immunological effects. Among of these effects the influence of pentoxifylline on the natural killer cell activity was studied. In in vitro experiments the human natural killer cell cytotoxicity was examined in the presence of pentoxifylline. In our clinical trial we investigated the topic whether this drug has an immunomodulatory effect while administering it for different periods. The natural cytotoxicity of macroangiopathic patients treated with pentoxifylline was compared with the values of healthy controls and patients suffering from vascular disease and obtaining no pentoxifylline therapy. Sixty two macroangiopathic patients and twenty healthy controls were investigated altogether. In the in vitro natural killer cell reaction we found that the pentoxifylline was able to suppress the cytotoxicity at any time of the reaction. The influence of pentoxifylline on natural killer cell activity was neither due to the expression of intercellular adhesion molecule-1, nor to the alteration of membrane fluidity. However, this drug significantly (p < 0.05) decreases the apoptosis of target cells. The natural killer cell activity of patients with chronic pentoxifylline therapy lasting for more than a year was proved to be significantly (p < 0.005) lower. The presence of vascular disease does not influence the natural killer activity by itself. Concluding our results we can state that the suppressing effect of pentoxifylline on natural killer cell activity needs to be taken into consideration in case of clinical diseases where this drug is administered chronically.

Neurotrophin-mediated neuroprotection by solid fetal telencephalic graft in middle cerebral artery occlusion: a preventive approach

In the present study, embryonic rat neocortex was implanted into the parietal subcortical area of adult naive animals. On the 7th day, the middle cerebral artery was permanently occluded ipsilateral to the graft. Twenty-four hours after middle cerebral artery occlusion, the extent of infarct was visualized by means of 2,3,5-triphenyltetrazolium chloride histochemistry and quantified in four different standardized coronal plains. Subsequently, the effects of fetal tissue grafting and those of transplantation were identified by using glial fibrillary acidic protein and nerve growth factor immunocytochemistry. The grafts integrated well into their new environment and significantly reduced the size of infarct in middle cerebral artery-occluded animals compared with both sham-operated and control rats 24 h postoperation. The underlying mechanism of this phenomenon might be an increased neurotrophic, particularly nerve growth factor, release by the grafted fetal tissue. Moreover, reactive astroglial cells may also trigger the neuroprotection by additional ischemia-induced nerve growth factor release. The present data demonstrate the potential neurotrophin-mediated protective effects of fetal brain tissue implanted into the adult rat brain before unilateral middle cerebral artery occlusion and the beneficial effects of astrocyte activation.

Natural killer cell mediated cytotoxicity against VERO target cells; the suppressive effect of pentoxifylline

The K-562 cell line is widely known and used as a NK cell target. In this study we report that VERO (African green monkey kidney epithelial cell line) is an excellent target of the human NK cell cytotoxicity. Considerable cytotoxicity was observed in a 4 h 51Cr release assay with nonadherent and immunomagnetically separated CD56+ NK cells from PBMC. On the contrary, adding K-562 cells as cold target to the assay the cytotoxicity significantly decreased. Using a standard chromium-release assay the NK cell activity (NKCA) against VERO cells was investigated in a population of healthy volunteers (mean value of cytotoxicity was 26.6%) and compared with the values of cytotoxicity against K-562 target cells (32.6%). The difference was not significant (P > 0.05). The suppressive effect of PTX on in vitro NK cell activity was observed at concentration of 100 microg/ml using VERO target cells as well as K-562 cells. Our studies provide the first evidence that the NK cell activity is suppressed in vitro by PTX using VERO cells as NK target cells.

Perturbation of the integrity of the blood-brain barrier by fibrinolytic enzymes

The action of fibrinolytic enzymes (plasmin, miniplasmin, neutrophil leukocyte elastase) on the blood-brain barrier is investigated. The binding and the effects of the fibrinolytic enzymes are studied in the first subcultivation of human brain capillary endothelial cells. 125I-labeled plasmin, miniplasmin and neutrophil leukocyte elastase bind to confluent monolayers of cultured endothelial cells with dissociation constants of 1 x 10(-8) mol/l, 4.8 x 10(-7) mol/l and 1.8 x 10(-8) mol/l, respectively, and the number of binding sites varies between 2.3 x 10(5) and 7.5 x 10(6) per cell. Following treatment of the cultured cells with purified and active-site titrated proteases, the changes in morphology of individual cells are analyzed with computerized morphometry. At low concentrations (in nanomolar range) all studied fibrinolytic proteases induce reduction of the cell area; the minimal size is achieved in 20-80 min after the application of an enzyme and the effect is completely reversed in 15 min after its removal. A possible in-vivo consequence of these in-vitro findings is studied in an organ-perfusion model: rat hemisphere is perfused with a protease solution followed by a circulating phase-borne tracer (horse-radish peroxidase). In perfused rat hemisphere, the fibrinolytic enzymes open the blood-brain barrier to the circulation-borne tracer. These results support the concept that fibrinolytic enzymes interact with the brain microvascular endothelium and thus affect the integrity of the blood-brain barrier through active cell contraction.

Accuracy of clinical operational diagnostic criteria for Alzheimer's disease in relation to different pathological diagnostic protocols

In this study we analysed the accuracy of two sets of clinical diagnostic criteria, the NINCDS/ADRDA and DSM-III-R, in relation to the currently used pathological diagnostic criteria for Alzheimer's disease (AD), the Khachaturian criteria, the Tierney A3 criteria and the CERAD protocol. The sensitivity of the individual clinical diagnostic criteria, NINCDS/ADRDA and DSM-III-R, is poor (34-58%) irrespective of the pathological diagnostic criteria applied for the definite diagnosis of AD. The combination of the NINCDS/ ADRDA 'possible' and 'probable dementia of the Alzheimer type' (DAT) categories has a high sensitivity (91-98%). However the combination resulted in very poor specificity (40-61 %). Thus, none of the clinical diagnostic criteria is satisfactory. We found similar results when we analysed the predictive value of these clinical diagnostic criteria. The positive predictive value of NINCDS 'probable DAT' category and that of the DAT diagnosis by DSM-III-R is very high (89-100%). This makes the use of these categories suitable for research purposes. However, the negative predictive value of both diagnoses is poor (33-63%), making these criteria unsuitable for diagnostic purposes in clinical practice.

Endothelial cells cultured from human brain microvessels produce complement proteins factor H, factor B, C1 inhibitor, and C4

The inflammatory mediators, cytokines and complement proteins are believed to regulate the sequential events during the development of lesions secondary to ischaemia and reperfusion. The endothelial cell monolayer of the brain microvasculature is the critical interface between the blood-borne mediators and brain tissue. The involvement of these cells in complement production and regulation has not been well documented. In the present study, expression of complement proteins (C1 inhibitor, factor H, factor B, C4) by cultured endothelial cells obtained from human brain microvessels has been characterized. Interferon gamma upregulates the production of all the complement factors studied. Serine proteases, plasmin and miniplasmin induce the expression of C4, decrease the level of ELISA detectable C1 inhibitor, and do not affect the production of factors H and B. These data indicate that complement proteins are expressed locally by the brain microvessels, and may modulate the inflammatory responses of brain tissue.

Nitric oxide production and MDR expression by human brain endothelial cells

The endothelium both initiates and responds to a cascade of events triggered by cytokines. Enhanced formation of NO, especially by inducible nitric oxide- synthase (i NOS), is largely stimulated by tumor necrosis factor (TNF). Nitrogen oxides are reactive intermediate molecules functioning in neural transmission, and vasodilatation. The aim of our study was to investigate the effect of TNF and Staphylococcus aureus, a TNF inducing agent on the NO production of brain endothelial cells in vitro. The effect of the same agent was investigated on the MDR expression of endothelial cells. Both TNF and Staphylococcus aureus resulted in enhanced NO production. Western blot analysis showed enhanced expression of iNOS, which could be inhibited by pentoxifylline, an inhibitor of TNF synthesis. Flow cytometric analysis revealed that the brain capillary endothelial cells exerted P-glycoprotein expression, which was not influenced by TNF. However, the mdr function itself in these cells was decreased by TNF. Cultured endothelial cells are excellent tools for the investigation of the possible connection between the NO production and MDR function, and for the estimation the effect of different agents influencing these activities, which might be important in blood-brain barrier function.

Regulation of endothelin release from human brain microvessel endothelial cells

After approval by the Local Ethical Committee, brain microvessel endothelial cells from human cadavers were isolated by enzymatic digestion and gradient centrifugation. Basal levels of endothelin-1 (ET) in the supernatant increased over time (3 h, 18.3 +/- 4.3 pg/ml; 6 h, 31.3 +/- 1.1 pg/ml; 24 h, 88.0 +/- 5.7 pg/ml; 48 h, 86.3 +/- 11.2 pg/ml, mean +/- SD). Tumor necrosis factor-alpha (TNF-alpha) (270 U/ml) increased ET concentration dose-dependently: 3 h, 190 +/- 70%; 24 h, 217 +/- 39%; 48 h, 207 +/- 5%; TNF-alpha at 210 U/ml: 3 h, 137%; 24 h, 170%; 48 h, 212% (values are relative changes from control, run in parallel to the stimulated wells). Interleukin-1 alpha (IL-1 alpha) (38.8 U/ml) also increased ET dose-dependently: (3 h, 129%; 24 h, 161%; 48 h, 212%; IL-1 alpha 1.4 U/ml: 3 h, 116%; 24 h, 122%; 48 h, 180%). Lipoprotein (a) (Lp(a)) had a dual effect on ET, increasing ET in the first 3 h but reducing it by the end of the 48-h observation period. This effect was not dose-dependent in the concentration range tested: Lp(a) 450 micrograms/ml; 3 h, 188%; 24 h, 91%; 48 h, 85%; Lp(a) 360 micrograms/ml: 3 h, 180%; 24 h, 94%; 48 h, 52%). Lp(a) reduced the stimulatory effect of cytokines on ET release. Maximal values at 48 h were TNF-alpha 207%, TNF-alpha + Lp(a) 91%, IL-1 alpha 212%, IL-1 alpha + Lp(a) 64%. In HPLC analysis, the total ET-like immunoreactivity co-eluted with the synthetic human ET standard. A cell culture of human brain microvessel endothelial cells was established. TNF-alpha and IL-1 alpha increased ET secretion, whereas Lp(a) had a dual effect. When given together, Lp(a) reduced the effect of cytokines on ETs.

Assessment of the pathological stages of Alzheimer's disease in thin paraffin sections: a comparative study

The staging method proposed by Braak and Braak allows the objective and reliable assessment of Alzheimer-related neurofibrillary pathology. Originally the method was designed for 100-microm thick sections. However, the use of thick sections proved to present difficulties in a routine neuropathology laboratory. In order to adapt the staging method for thin paraffin-embedded sections, we performed an inter- and intrarater study analysing the reliability of the staging method in thin sections. Statistical analysis of the data provided by six independent examiners in two rating sessions reveal kappa values of 0.6-0.8 for both the interrater and the intrarater reliability. The average rate of mistake of the examiners was rarely bigger than a half stage. We conclude that the adapted staging method in thin sections is strongly reliable and we recommend it for staging purposes in institutions where the preparation of thick sections would be difficult.

Beneficial effects of pentoxifylline treatment of experimental acute pancreatitis in rats

The purposes of this study were to determine the tumor necrosis factor (TNF) and interleukin-6 (IL-6) levels after the induction of acute necrotizing pancreatitis, and to establish the effects of pentoxifylline on cytokine production.

METHODS

acute pancreatitis was induced by the retrograde injection of 200 microliters taurocholic acid into the pancreatic duct in male Wistar rats. The serum amylase activity, the wet pancreatic weight/body weight ratio, and the TNF and IL-6 levels were measured. Seven mg/kg pentoxifylline were administered intraperitoneally at the time of operation 6, 12 or 24 h later. Rats were killed 6, 24, 48 or 72 h after the operation.

RESULTS

the TNF bioassay revealed high levels of TNF (30.2 +/- 5.4 U/ml, 35.0 +/- 5.0 U/ml and 36.6 +/- 6.0 U/ml) in the control group at 6, 24 and 48 h and (54.1 +/- 20 U/ml and 10.9 +/- 4.2 U/ml) in the pentoxifylline-treated group at 6 and 24 h, respectively, whereas the level had decreased to zero in the pentoxifylline-treated group at 48 h. The IL-6 bioassay likewise demonstrated high levels of IL-6 in the control group at 48 h and in the pentoxifylline-treated group at 6 and 24 h, and markedly decreased levels in the pentoxifylline-treated group at 48 h (7083 +/- 2844 pg/ml, 6463 +/- 1307 pg/ml, 10,329 +/- 5571 pg/ml vs 137.5 +/- 85.5 pg/ml, respectively, P < 0.05). The high mortality observed in the pancreatitis group (43%) was decreased by pentoxifylline administration to 11%.

CONCLUSION

these results demonstrate that pentoxifylline very effectively inhibits cytokine production in acute pancreatitis.

Intracytoplasmic sperm injection: laboratory set-up and injection procedure

Intracytoplasmic sperm injection (ICSI) as treatment for male-factor infertility has been introduced worldwide in the past few years in many laboratories using assisted reproduction techniques. Some changes in the existing set-up are necessary before implementing this procedure. The equipment can be divided into two groups: that required for preparation of the microtools and that required for the microinjection procedure itself. A pipette puller, grinder and microforge are necessary for preparation of the microtools. The correct settings and use of these instruments are of crucial importance in preparing a good needle, which in turn is crucial to the injection procedure itself. The microscope has to be equipped with a heated stage, correct optics and manipulators and injectors. The correct settings and use of this equipment also influence the injection procedure and may influence the success rate. Retrospective analysis of the evolution of ICSI in our centre clearly shows a marked improvement following the introduction of some modifications into the procedure. These modifications were (i) reducing the concentration of hyaluronidase used for cumulus and corona radiata removal, (ii) selecting a motile spermatozoon that was immobilized prior to the injection and (iii) aspiration of cytoplasm to ensure rupture of the oocyte membrane. The injection procedure itself can also be influenced by oocyte characteristics. It has been reported that the reaction of the oocyte to the penetration by the pipette has an influence on the success rate. The ICSI procedure has about the same success rate as IVF in cases of non-male infertility. However, work can still be done to improve the success rate of this procedure.

Temporal cortex synaptophysin mRNA is reduced in Alzheimer's disease and is negatively correlated with the severity of dementia

We measured synaptophysin mRNA in neocortical tissue from 7 prospectively assessed, pathologically verified normal individuals, 17 subjects with Alzheimer's disease (AD), and 13 subjects with a non-AD dementia. In temporal cortex (Brodmann area 21), synaptophysin mRNA was decreased in AD and non-AD dementia groups compared to controls. The loss was also present relative to polyadenylated mRNA content. Synaptophysin mRNA signal correlated negatively with the degree of dementia and negatively with the pathological severity of AD. In occipital cortex (Brodmann area 17) there were no differences between groups nor clinicopathological correlations. These data extend the evidence for a regional synaptic pathology in AD which affects synaptic protein gene expression by temporal cortex neurons.

Fine needle aspiration versus open biopsy for testicular sperm recovery: a controlled study in azoospermic patients with normal spermatogenesis

This retrospective controlled study aimed at comparing two techniques for recovering testicular spermatozoa in azoospermic patients undergoing intracytoplasmic sperm injection (ICSI). 102 men suffering from infertility because of obstructive azoospermia had ICSI using testicular spermatozoa recovered either by open excisional biopsy (n = 51), or by fine needle aspiration (FNA) (n = 51). A higher average number of spermatozoa were recovered after open biopsy than after FNA, but no significant differences in either fertilization rates or cleavage rates were observed after ICSI with spermatozoa retrieved by the two techniques. Neither was there any significant difference in ongoing pregnancy and implantation rates: in the FNA group, these figures were respectively 19.6% per cycle and 7.8% per embryo transferred and in the open biopsy group 21.6 and 7.1%. We conclude that ICSI with testicular spermatozoa recovered by FNA yields results comparable to those obtained with spermatozoa recovered by open biopsy in azoospermic patients with normal spermatogenesis. However a prospective study is needed to confirm the present results and to assess recovery rates and patient comfort for the two methods.

Neuronal cyclin expression in the hippocampus in temporal lobe epilepsy

This study used immunocytochemistry to explore the expression of cyclins A, B, D, and E and the apoptosis-associated Bax protein in hippocampal subfields of 35 lobectomy specimens with medial temporal lobe sclerosis removed for the treatment of temporal lobe epilepsy (TLE), 2 age-matched controls, and 2 elderly patients suffering from drug-responsive epilepsy. Cyclins A and D were not detected at all in neuronal nuclei. Cyclin E was only rarely detected in neuronal nuclei in drug-controlled and TLE groups and in controls. Cyclin B was expressed in significantly more neuronal nuclei in the hippocampi in TLE than in the other groups studied. The nuclear expression of these proteins suggested that neurons had reentered the cell division cycle and reached the G2 phase. The nuclear expression of cyclin B in the hippocampus from these patients was accompanied by neuronal cytoplasmic expression of the death-related Bax protein. We interpret these neuronal findings as evidence of cell cycle disturbances and a possible apoptotic mechanism of hippocampal neuronal cell death in TLE.

Experimental acute pancreatitis results in increased blood-brain barrier permeability in the rat: a potential role for tumor necrosis factor and interleukin 6

Pancreatic encephalopathy is a severe complication of acute pancreatitis. Proinflammatory cytokines may play a role in the development of multi-organ failure during pancreatitis. In the present study, we measured the changes in the blood-brain barrier (BBB) permeability concomitantly with the determination of serum tumor necrosis factor (TNF) and interleukin-6 (IL-6) levels in rats before, as well as 6, 24 and 48 h after the beginning of intraductal taurocholic acid-induced acute pancreatitis. Cytokine concentrations were measured in bioassays with specific cell lines (WEHI-164 for TNF and B-9 for IL-6), while the BBB permeability was determined for a small (sodium fluorescein, molecular weight (MW) 376 Da), and a large (Evans' blue-albumin, MW 67000 Da) tracer by spectrophotometry in the parietal cortex, hippocampus, striatum, cerebellum and medulla of rats. The serum TNF level was significantly (P < 0.05) increased 6 and 24 h after the induction of pancreatitis, while the IL-6 level increased after 24 and 48 h. A significant (P < 0.05) increase in BBB permeability for both tracers developed at 6 and 24 h in different brain regions of animals with acute pancreatitis. We conclude that cytokines, such as TNF and IL-6, may contribute to the vasogenic brain edema formation during acute pancreatitis.

Surgical sperm retrieval for intracytoplasmic sperm injection

The introduction of intracytoplasmic sperm injection (ICSI) provides new hope for many couples suffering from the most untreatable forms of male infertility as ICSI can also be successfully performed using epididymal or testicular spermatozoa. Testicular spermatozoa may be recovered from testicular tissue in every patient with excretory azoospermia, but also in about half of patients with secretory azoospermia. The strongest parameter to predict successful testicular sperm recovery is histopathological examination of a testicular biopsy, especially in patients with some form of germ-cell aplasia. Even in our series of Klinefelter patients, testicular sperm were recovered in eight out of 15 patients and after seven ICSI cycles combined with preimplantation diagnosis, two singletons were born. Less invasive techniques such as percutaneous fine-needle aspiration have been introduced and may yield comparable success rates in patients with normal testicular function. The high fertilization rates after testicular sperm recovery and ICSI and the favourable implantation rates may therefore render microsurgical epididymal sperm aspiration (MESA) obsolete in the future for patients with normal spermatogenesis. Besides, the use of cryopreserved testicular spermatozoa may become an alternative to repeated surgery for obtaining testicular tissue for subsequent ICSI treatment cycles.

A hemagglutinin-based multipeptide construct elicits enhanced protective immune response in mice against influenza A virus infection

Multipeptide constructs, comprising adjacent sequences of the 317-341 intersubunit region of immature influenza A hemagglutinin (H1N1), were designed and the functional properties of these branched peptides were compared to that of the corresponding linear peptides. In vivo studies revealed that the immunogenicity of the peptides was dependent on the presence of the hydrophobic fusion peptide (comprised in FP3), encompassing the N-terminal 1-13 sequence of the HA2 subunit. Antibody and T cell recognition, however, was directed against the 317-329 HA1 sequence, comprised in the P4 peptide. Multiple copies of P4, covalently linked by branched lysine residues, significantly enhanced the efficiency of antibody binding and the capacity of peptides to elicit B- and T-cell responses. A fraction of peptide induced antibodies reacted with immature or with proteolitically cleaved hemagglutinin (HA) molecules pretreated at low pH. Immunization with a multipeptide construct, (P4)4-FP3, not only resulted in elevated antibody and T cell responses but conferred enhanced protection against lethal A/PR/8/34 (H1N1) infection as compared to its subunit peptides. The beneficial functional properties of this artificial peptide antigen may be acquired by multiple properties including: (i) stabilized peptide conformation which promotes strong, polyvalent binding to both antibodies and MHC class II molecules; (ii) appropriate P4 conformation for antibody recognition stabilized by the covalently coupled fusion peptide, resulting in the production of virus cross reactive antibodies which inhibit the fusion activity of the virus; (iii) activation of peptide specific B cells which potentiate antigen presentation and peptide specific T cell responses; and (iv) generation of helper T cells which secrete lymphokines active in the resolution of infection.

[Sandostatin treatment in postoperative external digestive fistulae]

The aim of the conservative treatment of postoperative external digestive fistulae is to obtain a reduction of the output, thus favoring spontaneous closure and shortening outcome. A retrospective comparative study has been performed on two groups of patients with postoperative anastomotic gastrointestinal and pancreatic fistulae. Group A included 18 cases (14 anastomotic, 4 pancreatic fistulae) receiving conventional treatment only. Group B included 25 cases (18 anastomotic and 7 pancreatic fistulae) in which Sandostatin was associated to conventional therapy, using daily doses ranging from 0.1 mg to 0.3 mg, administered after variable intervals after fistulas' occurrence. Duration of treatment ranged from 1 to 25 days. In group A, 27.77% of the cases were cured in comparison with group B in which the healing rate increased to 56%. Global hospital mortality rate was 25.58% (11 cases). In group A this was 44.44% (8 cases) in comparison with group B with 12% (3 cases) only. As a conclusion of our study, the use of Sandostatin is remarkable effective in the treatment of external digestive postoperative fistulae. Thus a doubling of healing rate and a reduction by 73% of mortality rate was achieved.

Idiopathic scoliosis--new surgical methods or search for the reasons

Idiopathic scoliosis (IS) is a deformity of the spine whose aetiology is unknown despite of extensive clinical and basic research work. The significance of this disease lies in the consequences of a spine deformity (deformation of the chest, compromise of the cardio-pulmonar function, compression of the neurological elements, severe somatic and psychological sufferings). According to statistical data, one third of the idiopathic scoliotic cases progress and need surgical intervention. Cotrel and Dubousset introduced the three dimensional correction surgical method for the treatment of spine deformities in 1983 (CD method). The authors report on the application of the CD method for the treatment of IS from 1991 to date. After the operation of 36 patients they give an account of good results and report on the modifications of the surgical technique on the basis of their experiences. Aware of the late consequences of the surgical treatment of IS the authors started with the investigation of the aetiology of the disease in order to introduce a causal treatment. As for the aetiological background of IS, data on the role of heritable factors were relevant only. They gave a hint to start with studies aimed at the investigation of genetic determinants of the syndrome. I aberration of chromosome #10 [karyotype: inv(10)(p11q26)]. In one of the cases there was a multiple familial occurrence of the syndrome coupled with the same anomaly of the karyotype. The probands' father and grandfather all had the same pattern of scoliotic deformity and the same aberrant karyotype of chromosome #10 was found both in the proband and his father. Preparation of genomial DNA from peripheral blood of the patients was started. Fragment length polymorphism (RFLP) examination with PCR technique using oligonucleotide primers specific for chromosome #10 and for regulatory genes of left-right body assymetry is underway.

Scleral reinforcement in progressive myopia and intraoperative ultrasound control of the cadaver fascia lata strip

Scleral reinforcement (sustentaculum sclerae) is one of the operations against myopia. During the progression of myopia the eye grows. The chorioretinal layer can only moderately follow the expansion of the sclera, and mostly this is the cause of the complications that can cause permanent visual acuity decrease. The aim of the operation is to strengthen the posterior part of the sclera by implantation of a cadaver fascia lata strip, that slows down or stops the expansion of the eyeball, and this way prevents the development of complications. At our Department we perform the Snyder-Thompson technique. Between 1984 and 1994 343 operations were performed at our Department. We followed up the changes of the axial lengths by ultrasound (A-mode) examinations. The axial length decreased in 43.7% remained unchanged in 22.2% and increased in 34.1% of the cases. We controlled the location of the strip intra- and postoperatively with B-mode ultrasound. Nowadays scleral reinforcement is still the only possibility to stop or slow down the expansion of the eyeball in cases of progressive high myopia.