Early metabolic changes in peripheral blood cells of renal transplant recipients treated with cyclosporine A

We histochemically examined (phosphatase acid-AcP, phosphatase alkaline-ALP, succinate dehydrogenase-SDH, lactate dehydrogenase-LDH) the peripheral blood of renal transplant recipients and controls before (day 0) and after Cyclosporine A (CsA) treatment (days 1, 2, 7 and 30). We wanted to detect the metabolic changes induced in the CsA resistant cells (leucocytes) by CsA and to evaluate the early effects determined by the drug. There was no difference in enzyme activities between the control group and renal patients before CsA treatment (day 0). AcP and ALP activity increased 1 day after CsA administration and became similar to the control by the day 30. LDH activity increased one day after CsA treatment and remained high during the treatment period (30 days), while SDH activity did not change. These enzymatic variations may suggest that the LDH enzyme is involved in the drug degradation as are other phosphatase and oxidoreductase enzymes (i.e. cytochrome P450). Moreover, the high activity of LDH, the enzyme responsible for interconversion of pyruvate in lactic acid, would indicate that anaerobic glycolysis is preferentially used in the pyruvate pathway. However, SDH did not seem to be directly involved in CsA metabolism. Our findings showed that the CsA treatment induced clear variations of the activity of the cellular phosphatase and oxidoreductase enzymes from the first days of drug administration. The variation of the enzymes studied and the appearance time and duration of the metabolic changes, may be markers of the cellular stress due to CsA internalization.

Cell-specific expression of heat shock transcription factors 1 and 2 in unstressed rat spinal cord

We investigated the intracellular distribution of heat shock factors 1 and 2 (HSF1, HSF2) in rat spinal cord by immunoblotting and immunohistochemistry using selective policlonal antibodies. Our results showed that both HSF1 and HSF2 were expressed in spinal cord cells (both neurons and glia) but at different intensity and cell localization. HSF1 was unusually distributed in the perinuclear compartment of selected neurons of the gray matter while astrocytes, oligodendrocytes and ependymal cells were predominantly stained in the nucleus. HSF2 was expressed at lower levels than HSF1 and was scattered in both nucleus and cytoplasm of the motoneurons of the ventral horns while glial cells again showed a nuclear positivity. This study suggested that the different ability of neurons vs. glial cells to react against adverse conditions might well be correlated with the different constitutive localization of HSFs.

Clinical validation of the avidin/indium-111 biotin approach for imaging infection/inflammation in orthopaedic patients

We report here the results of a validation study of the avidin/indium-111 biotin approach in patients with skeletal lesions. This study involved 54 patients with orthopaedic conditions: 20 patients with intermediate suspected osteomyelitis of the trunk, 19 patients with infection/inflammation of prosthetic joint replacements, and 15 patients with suspected osteomyelitis of appendicular bones. Avidin (3 mg) was injected as an i.v. bolus, followed 4 h later by 111In-biotin; imaging was acquired 30 min and 16-18 h after administration of 111In-biotin. Technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO)-labelled leucocyte scintigraphy was performed in 39/54 patients. The overall sensitivity of the avidin/111In-biotin scan was 97.7% (versus 88.9% for 99mTc-HMPAO leucocyte scintigraphy). While the diagnostic performance of avidin/111In-biotin scintigraphy was similar to that of 99mTc-HMPAO leucocyte scintigraphy in patients with prosthetic joint replacements or osteomyelitis of appendicular bones, the avidin/111In-biotin approach clearly performed better than 99mTc-HMPAO leucocyte scintigraphy in patients with suspected osteomyelitis of the trunk (100% sensitivity, specificity and accuracy versus 50% sensitivity, 100% specificity and 66.7% accuracy for 99mTc-HMPAO-leucocyte scintigraphy). These results demonstrate the feasibility of the avidin/111In-biotin approach for imaging sites of infection/inflammation in the clinical setting. Although no systematic advantages of avidin/111In-biotin scintigraphy were found versus 99mTc-HMPAO leucocyte scintigraphy, the newer scintigraphic method is more practicable and involves lower biological risk for the operators.

Group I mGluR activation causes voltage-dependent and -independent Ca2+ rises in hippocampal pyramidal cells

Application of the metabotropic glutamate receptor (mGluR) agonist (1S, 3R)-1-aminocyclopentane-1,3-dicarboxylic acid (ACPD) or the selective group I mGluR agonist (S)-3,5-dihydroxyphenylglycine (DHPG) depolarized both CA3 and CA1 pyramidal cells in guinea pig hippocampal slices. Simultaneous recordings of voltage and intracellular Ca2+ levels revealed that the depolarization was accompanied by a biphasic elevation of intracellular Ca2+ concentration ([Ca2+]i): a transient calcium rise followed by a delayed, sustained elevation. The transient [Ca2+]i rise was independent of the membrane potential and was blocked when caffeine was added to the perfusing solution. The sustained [Ca2+]i rise appeared when membrane depolarization reached threshold for voltage-gated Ca2+ influx and was suppressed by membrane hyperpolarization. The depolarization was associated with an increased input resistance and persisted when either the transient or sustained [Ca2+]i responses was blocked. mGluR-mediated voltage and [Ca2+]i responses were blocked by (+)-alpha-methyl-4-carboxyphenylglycine (MCPG) or (S)-4-carboxy-3-hydroxyphenylglycine (4C3HPG). These data suggest that in both CA3 and CA1 hippocampal cells, activation of group I mGluRs produced a biphasic accumulation of [Ca2+]i via two paths: a transient release from intracellular stores, and subsequently, by influx through voltage-gated Ca2+ channels. The concurrent mGluR-induced membrane depolarization was not caused by the [Ca2+]i rise.

Abnormal myo-inositol and phospholipid metabolism in cultured fibroblasts from patients with ataxia telangiectasia

Ataxia telangiectasia (AT) is a complex autosomal recessive disorder that has been associated with a wide range of physiological defects including an increased sensitivity to ionizing radiation and abnormal checkpoints in the cell cycle. The mutated gene product, ATM, has a domain possessing homology to phosphatidylinositol-3-kinase and has been shown to possess protein kinase activity. In this study, we have investigated how AT affects myo-inositol metabolism and phospholipid synthesis using cultured human fibroblasts. In six fibroblast lines from patients with AT, myo-inositol accumulation over a 3-h period was decreased compared to normal fibroblasts. The uptake and incorporation of myo-inositol into phosphoinositides over a 24-h period, as well as the free myo-inositol content was also lower in some but not all of the AT fibroblast lines. A consistent finding was that the proportion of 32P in total labeled phospholipid that was incorporated into phosphatidylglycerol was greater in AT than normal fibroblasts, whereas the fraction of radioactivity in phosphatidic acid was decreased. Turnover studies revealed that AT cells exhibit a less active phospholipid metabolism as compared to normal cells. In summary, these studies demonstrate that two manifestations of the AT defect are alterations in myo-inositol metabolism and phospholipid synthesis. These abnormalities could have an effect on cellular signaling pathways and membrane production, as well as on the sensitivity of the cells to ionizing radiation and proliferative responses.

Replicating myoblasts and fused myotubes express the calcium-regulated proteins S100A1 and S100B

We investigated the expression and the subcellular localization of S100A1 and S100B, two Ca(2+)-binding proteins of the EF-hand type, in replicating myoblasts and fused myotubes. Northern blot and reverse transcriptase-polymerase chain reaction analyses revealed the presence of S100A1 mRNA and S100B mRNA respectively, in myoblasts. Immunofluorescence and immunogold electron microscopy were used to localize individual proteins in myoblasts and myotubes. In the present report we document that: (1) in replicating myoblasts S100B is localized to intracellular membranes, including Golgi membranes, vimentin intermediate filaments (IFs) and microtubule (MT) structures; (2) in the same cells S100A1 is found associated with intracellular membranes; (3) following treatment of replicating myoblasts with colchicine, a fraction of S100B remains colocalized with bundled and collapsed vimentin IFs, whereas another fraction follows the destiny of endoplasmic membranes; (4) under the same conditions S100A1, like a fraction of S100B, follows the collapse of the endoplasmic reticulum around the nucleus; and (5) in fused myotubes S100A1 is found diffusely in the cytoplasm, whereas S100B is mostly found associated with vimentin IFs. These data suggest that in the skeletal myogenic cell line used in the present study S100A1 and S100B might share binding sites on or close to intracellular membranes, but display a significant degree of target specificity with respect of IFs and MTs. The results of these analyses suggest that expression of S100B in skeletal muscle cells may be developmentally regulated and lend support to the possibility that S100B might regulate the MT and IF dynamics.

Preoperative serum E-cadherin assay in patients with ovarian carcinoma

E-cadherin is a 120-kDa transmembrane glycoprotein involved in the calcium dependent adhesion of epithelial cells. Soluble E-cadherin fragment levels have been found to be significantly elevated in patients with different malignancies when compared to healthy controls (Katayama M. et al. Br. J. Cancer 69, 580-585, 1994). The aim of this paper was to assess the clinical relevance of preoperative serum E-cadherin assay in patients with ovarian carcinoma. E-cadherin was measured with a solid phase enzyme immunoassay based on a sandwich method using two mouse monoclonal anti-human E-cadherin antibodies. Preoperative serum E-cadherin levels were higher in 55 patients with ovarian carcinoma than in 31 patients with benign ovarian disease as controls, even though the difference did not reach the statistical significance (median value, range: 6615 ng/ml, 444-26,092 ng/ml versus 5531 ng/ml, 1548-12668 ng/ml, p = 0.063). However, the subset of the 36 patients with FIGO stage III-IV ovarian carcinoma had significantly higher antigen levels (median value, range: 7205 ng/ml, 444-26,092 ng/ml) when compared to controls (p = 0.039). Among patients with advanced ovarian carcinoma, preoperative serum E-cadherin correlated neither with the common clinico-pathological prognostic variables nor with the response to chemotherapy and survival. Our data seem to show that the preoperative serum E-cadherin assay does not offer useful clinical information for the management of patients with ovarian carcinoma.

Association of S100B with intermediate filaments and microtubules in glial cells

Previous in vitro studies have shown that the Ca2+-regulated S100B protein modulates the assembly-disassembly of microtubules (MTs) and type III intermediate filaments (IFs). In the present report, by double immunofluorescence cytochemistry S 100B was localized to both GFAP/vimentin IFs and MTs as well as to centrosomes in U251 glial cells. In cells treated with the MT-depolymerizing agent, colchicine, S100B remained associated with the rearranged GFAP IFs throughout the cell and, at the cell periphery, vimentin IFs. In cells treated with the MT stabilizing agent, taxol, S100B followed partly the rearrangement of MTs and partly the rearrangement of IFs. Under the latter condition, bundles of MTs with their associated S100B appeared surrounded and/or flanked by rearranged IFs with their associated S100B. Colocalization of S100B with closely arranged IFs and MTs was best evident in cells manipulated with taxol and in triton-cytoskeletons. In these cases, MTs and their associated S100B appeared surrounded and/or flanked by and/or intermingled with IFs and their associated S100B. Also, a preferential association of S100B with GFAP vs. vimentin IFs could be observed near the nucleus where colocalization of S100B with MTs was also maximal. Condensation of IFs and alteration of the MT network caused by treatment of cells with the phosphatase inhibitor, okadaic acid, resulted in a concomitant condensation/alteration of the S100B immunoreactivity. The present results lend support to the possibility that S100B may be an important factor implicated in the regulation of the dynamics of MTs and IFs.

Expression of Fos immunoreactivity in the rat supraspinal regions following noxious visceral stimulation

We used immunohistochemical detection of the Fos protein to study the neuronal activation in the brain of methoxyfluorane-anesthetized rats after noxious deep somatic or visceral stimulation. The anesthesia was effective in triggering gene induction in many brain regions. Nevertheless, Fos appeared de novo in several brain nuclei following noxious stimulation in anesthetized animals. This could be of clinical relevance, as it suggests that the gas anesthetic does not suppress noxious stimulus-evoked reactivity in brain neurons. Two types of visceronociceptive stimuli were used to compare the effects of a diffuse visceral inflammation (peritoneal inflammation) with those of a more restricted inflammation (urinary bladder inflammation). In the same supraspinal areas, there were very few immunostained neurons in unstimulated controls, whereas Fos-positive cells were slightly more numerous in anesthetized controls and significantly more numerous after noxious stimulation. The peritoneal inflammation induced more Fos-labeled neurons than the restricted visceral stimulation. Labeled cells were found in these cases mainly in the ventrolateral medulla, parabrachial complex, dorsal raphe nucleus, periaqueductal gray, several hypothalamic and thalamic nuclei, amygdaloid complex, and cortex. Altogether these findings indicated that somatic and visceral inputs generally activate the same neuronal groups. However, a separation between the activation of somatic and visceral pathways was found in some brain nuclei, such as the parabrachial complex, hypothalamic, and thalamic nuclei.

Trocar site tumor recurrences. May pneumoperitoneum be responsible?

BACKGROUND

Port site metastasis following laparoscopy for cancer is reported with increasing frequency and represents one of the most important limitations of the technique.

METHODS

A scintigraphic model was utilized to evaluate a possible role of pneumoperitoneum in tumor cell dissemination. Labeled red blood cells (RBC) were injected at the level of the gallbladder bed during laparoscopic cholecystectomy (LC) performed for symptomatic cholecystolithiasis. LC was performed in two groups with standard CO2 pneumoperitoneum: in one group an endobag for retrieval of the specimen was utilized. In one group a gasless LC with endobag was performed.

RESULTS

Radioactivity in the area of the trocar introduction was observed in almost all the patients who underwent standard (CO2) LC but represented a rare event in patients treated with the gasless method. The utilization of a protective bag for the extraction of the surgical specimen did not modify significantly the results. Moreover all patients treated with pneumoperitoneum demonstrated a wide intraperitoneal diffusion of the tracer not observed in gasless patients.

CONCLUSIONS

The results of this study confirm that pneumoperitoneum may play an important role in the evolution of port site metastasis after laparoscopy for gastrointestinal cancer.

Supraspinal connections and termination patterns of the parabrachial complex determined by the biocytin anterograde tract-tracing technique in the rat

We have re-evaluated, using the anterograde tracer biocytin, supraspinal efferent projections from the parabrachial complex (PBN) to gain new information about the nature of its connections and nerve terminal patterns. We selectively injected biocytin into the 3 main regions of the nucleus (lateral PBN, medial PBN and Kölliker-Fuse nucleus). We observed distinct groups of ascending and descending fibres of different calibre from the PBN running throughout the brain and reaching many brain areas involved in the regulation of autonomic function. Here we detected labelled bouton-like terminals and fibres with en-passage varicosities. The ascending efferents from the lateral PBN mainly reached the reticular, raphe and thalamic nuclei, the zona incerta (ZI), central nucleus of the amygdala (CeA) and lateral area of the periaqueductal grey (PAG). Thin descending efferents reached the ventral region of the solitary tract nucleus (STN). The ascending efferents from the medial PBN were seen in the raphe nuclei, reticular nuclei, ventral and lateral areas of the PAG, thalamic nuclei, and in the medial and lateral nuclei of the amygdala. Descending efferents were seen in the STN and in some reticular nuclei. The ascending projections from the Kölliker-Fuse targeted the ventral area of PAG, CeA, ZI, lateral hypothalamic area, ventromedial thalamic nucleus and, with only a few terminals, the ipsi and contralateral reticular area. A large number of descending efferents reached STN, caudal and paragigantocellular reticular nuclei. The higher sensitivity of biocytin compared with other types of markers allowed us to determine more effectively the distribution, nature and extent of the supraspinal PBN connections. This suggested that in several nerve circuits the PBN probably plays a more important role than previously thought.

IL-12 acts directly on DC to promote nuclear localization of NF-kappaB and primes DC for IL-12 production

We analyzed the expression of an IL-12 receptor by fresh dendritic cells (DC) and a DC line. Using RT-PCR, RNAse protection, and electrophoretic mobility shift assay analysis, we found that DC possess an IL-12 receptor with beta1 subunit (downstream box 1)-related differences from that on T cells. IL-12 signaling through this receptor involved members of the NF-KB but not STAT family. The unique properties of the IL-12 receptor on DC, characterized by a single class of binding sites with a Kd of about 325 pM, may underlie rather unique effects, such as IFNgamma-independent augmentation of class II antigen expression and priming for LPS-induced production of IL-12.

Serum macrophage colony-stimulating factor (M-CSF) levels in patients with epithelial ovarian cancer

The preoperative macrophage colony-stimulating factor (M-CSF) levels were measured in serum samples from 56 patients with epithelial ovarian cancer and 68 patients with benign ovarian disease who had undergone laparotomy. M-CSF values were significantly higher in the former (median, range: 2.18, 0.70-10.00 ng/ml versus 1.19, 0.17-5.54 ng/ml, P < 0.0001), and were not significantly related to stage, histology, grade of differentiation, age, and residual disease after first surgery. M-CSF concentrations were also measured in 163 serum samples drawn from patients with stage III-IV epithelial ovarian cancer at different times since the first surgery. M-CSF values were higher in the 81 samples from patients with clinically evident disease than in the 82 samples from patients with no clinical evidence of disease (median, range: 2.13, 0.60-10.00 ng/ml versus 1.05, 0.40-10.00 ng/ml, P < 0.0001). M-CSF levels before second-look laparotomy were similar in the 18 patients who showed persistent disease at surgical reevaluation and in the 11 patients who achieved pathological complete response (median, range: 1.26, 0.70-3.27 ng/ml versus 0.94, 0.46-4.23 ng/ml, P = NS). M-CSF concentrations were raised (> or = 1.70 ng/ml) only in 1 (14.3%) of the 7 samples from patients with clinically evident disease and serum CA125 < 35 U/ml, and only in 5 (38.5%) of the 13 samples from patients with positive second-look findings and serum CA125 < 35 U/ml. In conclusion, serum M-CSF levels correlated with the clinical status of disease in patients with epithelial ovarian cancer. However, the concomitant determination of serum M-CSF seems to add little to the CA125 assay alone in the monitoring of patients with this malignancy.

Dendritic arborization and spines of the neurons of the cat and human periaqueductal gray: a light, confocal laser scanning, and electron microscope study

Neurons of the periaqueductal gray (PAG) have an extensive dendritic tree which plays an important role in the neuronal circuits supporting the functional activities of this region. The complexity of the local circuits is increased by the occurrence of dendritic spines. We have compared the dendritic and spine organization in the cat with that of man in order to verify whether an inverse relationship exists between dendritic tree extension and spine density and complexity. Sections of cat and human PAG prepared according to the Golgi-Cox method were studied with the conventional light microscope (LM) and the confocal laser scanning microscope (CLSM). The cat PAG was also studied at the electron microscopic level. The light microscopic study provided the morphoquantitative characteristics of the dendritic arborization and spines of the multipolar and fusiform neurons of the human and cat PAG. The CLSM methodology, thanks to the three-dimensional reconstruction of the neurons and the rotation of the reconstructed images, brought into view dendritic branches and spines that could not have been observed at the LM, thereby showing a wider dendritic tree and more numerous spines. The data combined from LM and CLSM demonstrate that in both species most spiny neurons are multipolar and probably projection neurons. In man, the multipolar neurons show a more extensive dendritic tree due to a wider secondary ramification, which would seem to be balanced by more numerous spines in cat. At the electron microscopic level, axo-dendritic synapses are numerous and show symmetrical and asymmetrical junctions in equal proportions; furthermore, the great majority of the spines are in contact with synaptic boutons which contain round vesicles and make predominantly asymmetrical contacts features which indicate excitatory activity. The combined use of different techniques gave a complete picture of the dendritic tree and spines of the neurons of human and cat PAG and showed a wider dendritic surface available for the receipt of the synaptic contacts than had been reported previously. Furthermore, our findings demonstrate that the PAG dendritic spines are important and specific structures in the synaptic complex of the neuropil, suggesting that they might create a local device to modulate and integrate the afferent inputs, probably in an excitatory way. The differences observed in the two species suggest that afferent information might be handled in different ways in human and cat PAG.

Ultrastructural study of the alterations in spinal ganglion cells of rats chronically fed on ethanol

A study was conducted to find the effects of chronic alcohol (EtOh) administration on the rat dorsal root ganglion (DRG) cells in vivo. Morphoquantitative changes of the cytoplasmic organelles in neurons and satellite cells (SC) of lumbar DRG of animals fed with 20 and 40% of EtOH for 6 months were determined at the electron microscopic level. Stereological methods were used to quantitatively evaluate the changes in the neuronal Golgi fields, in the lysosomal system components called dense bodies (DB), in the mitochondria, and in the cytoplasmic perikaryal projections (PP) characteristic of DRG neurons. Prolonged consumption of 20% EtOh was well tolerated by neurons. There were, however, some structural modifications in the studied organelles, and there was a significant increase in the neuronal surface. In SC the number of mitochondria and DB increased significantly. Treatment with 40% EtOH produced massive organelle alterations in both neurons and SC, including disruption of the PP, markedly reducing the neuronal surface area. The architecture of the SC sheath appeared disorganized. The alterations resembled those of senescence, and indicated that a high dose of EtOH (or its metabolites) had a profound disruptive effect on the organelles and on the membrane systems of the DRG cells. The SC of the DRG units from the animals fed with EtOH were the first to show significant morphological alterations. When the architecture of the SC sheath already showed evident signs of disorganization, the neuronal body was just beginning to show morphological damage. These results suggest that the progressive disorganization of the SC sheath is a probable source of complication in peripheral neuropathy.

Mitochondrial membrane potential and DNA stainability in human sperm cells: a flow cytometry analysis with implications for male infertility

Sperm cells from control donors of proven fertility and men from barren couples were studied by conventional procedures, i.e., light microscopy as well as flow cytometry. Light microscopy analysis of semen included the measurement of spermatozoa concentration, morphology, and motility. All the men from barren couples were asthenozoospermic at the conventional analysis of semen samples. Flow cytometry was applied to study two important parameters of sperm cells: mitochondrial membrane potential (MMP) assessed by the cationic dye JC-1 and DNA stainability with propidium iodide (PI). JC-1 staining was more reliable than the classical procedure used for this purpose, i.e., rhodamine 123 (Rh123) staining, and allowed us to show a positive correlation between MMP and spermatozoa motility. Regarding DNA analysis, a higher relative percentage of immature spermatozoa, showing a high accessibility of DNA to the intercalating PI fluorochrome, was found in men from barren couples compared to donors of proven fertility. The relative percentage of immature spermatozoa was significantly higher in semen from oligoasthenozoospermic subjects. Moreover, a positive correlation was found between immature spermatozoa, as evaluated by PI staining, and cells with depolarized mitochondria, as evaluated by JC-1 staining, suggesting that spermatozoa defective for nuclear maturity could be functionally defective cells. No correlation between immature spermatozoa determined by FCM and immature spermatozoa determined by light microscopy was found, suggesting that these two techniques assess sperm cell maturity at different levels.

Induction of NADPH-diaphorase activity in the rat periaqueductal gray matter after nociceptive visceral stimulation

Nitric oxide (NO) is a neuronal messenger that it is thought to be involved in the nociceptive transmission modulation. The activity of nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) was shown to be identical to NOS activity in the brain. Since the periaqueductal gray matter (PAG) plays an important role in pain perception and antinociception this study was carried out to monitor the expression of NADPH-d in PAG after nociceptive visceral stimulation. Our data showed that the noxious visceral stimulation significantly increased NADPH-d positive neurons and that these neurons were localized in the ventrolateral areas of the PAG. These findings suggest that NO in the PAG may play a role in pain modulation and antinociception.

Effect of combined Cyclosporine A and liposome encapsulated dichloromethylene diphosphonate on the organisation of the rat thymus: evidence for a role of macrophages in guiding the post Cyclosporine A thymic reorganisation

Cyclosporine A (CsA) is a powerful immunosuppressant inducing marked involution of the thymic medulla, and disappearance of interdigitating cells (IDCs) and reducing the number of macrophages (Mphi). Usually, while the thymus of rats receiving a short course of CsA promptly recovers after stopping CsA treatment, long term CsA treatment, like mediastinal irradiation, impairs the normal thymic recovery and is thought to be responsible for the development of autoimmune diseases. In the present study we evaluated the role played by the IDCs and Mphi in the normal recovery of the thymic histology at light and ultrastructural level. Besides CsA administration, we also used liposome-encapsulated dichloro-methylene-diphosphonate (lip-CL2MDP), that induces a total depletion of the Mphi resistant to CsA. After a short (21 days) course of CsA and lip-CL2MDP administration, we did not observe the normal recovery of the thymic parenchyma but only cortical zones consisting of lymphoblasts, epithelial cells and Mphi. The CsA/lip-CL2MDP treatment determining the loss of IDCs and Mphi and consequently the loss of the normal thymic histology seems to simulate in the rats, the long term CsA treatment or the mediastinal irradiation. The results obtained suggest that the loss of IDCs and the depletion of Mphi interfere with the normal thymic recovery. The delay in the recovery of I DCs could be a consequence of the absence of macrophages. These findings would indicate that the IDCs, determining the negative selection of T-lymphocytes, are the main cells responsible for the thymic microenvironment.

Changes in diastolic function and collagen content in normotensive and hypertensive rats with long-term streptozotocin-induced diabetes

We investigated the relationship between left ventricular diastolic function and interstitial collagen content in the endocardium, mesocardium and epicardium of transverse sections of the heart, using an image analysis system in normotensive and hypertensive long-term streptozotocin (STZ) diabetic rats. STZ-induced diabetes was characterised by elevated blood glucose, polyuria, polydypsia and loss of body weight. In vivo systolic blood pressure was 165 +/- 4, 136 +/- 3 and 129 +/- 7 mmHg in hypertensive and normotensive diabetic rats and age-matched controls, respectively. Heart rate was significantly lower (P < 0.01) in diabetic rats (283 +/- 8 and 280 +/- 10 beats min-1 in normotensive and hypertensive rats, respectively) than controls (393 +/- 18 beats min-1). Pressure-volume (P-V) curves were studied in isolated Langendorff perfused hearts at rest and after 20 min global ischaemia and 30 min reperfusion 6 months after induction of diabetes. Left ventricular volumes were significantly smaller in diabetic rats than age-matched controls, but volumes normalised for heart weight were higher in normotensive (by 28%) and hypertensive (by 10%) diabetic rats. Slopes of end-diastolic P-V curves were similar between groups in basal conditions, but left ventricular systolic P-V curves were steeper in normotensive and flatter in hypertensive diabetic hearts. Post-ischaemic left ventricular end-diastolic pressure was significantly higher than the pre-ischaemic value at comparable increments of volume in each group. Collagen content significantly increased in the heart of rats with STZ-diabetes both in the free left ventricular wall and septum, and suggested this may play a role in the cardiac defects in contractility and relaxation in our experimental conditions. These results indicate that diabetes, irrespective of associated hypertension, can cause major changes in cardiac performance and susceptibility to ischaemia and reperfusion.

[Sinusoscopy in stomatology. Review of a 5-year clinical experience]

BACKGROUND

Investigative sinus endoscopy for purely diagnostic purposes has become an important therapeutic tool for disorders of the paranasal system thanks to the enormous technological developments of the last twenty years.

METHODS

In a retrospective study, sinus endoscopies carried out between 1990 and 1994 on 57 patients, mean age 43 years, were subjected to critical re-evaluation, with the aim of evaluating the efficacy of endoscopic treatment. In the first phase, the documentation available for each patient was examined; it included clinical data, preoperative traditional and CT radiographs, rhinoscopic and sinus endoscopic findings. Once the analysis of the available documentation had been completed the patients were recalled and subjected to clinical and radiological evaluation. Radiographic examination was carried out by traditional radiography.

RESULTS

CT scanning was only performed for those patients in whom the clinical findings indicated a possible relapse. Immediate and delayed complications occurring after the endoscopic sinus surgery were taken into consideration.

CONCLUSIONS

In conclusion, sinus endoscopy is a fundamental instrumental investigation in the diagnosis of rhinosinusopathies. It can no longer be considered as only a diagnostic investigation able to provide clear visual images, it also allows specimens to be taken for bacteriological, micological, cytological and histological analysis. Furthermore, endoscopic surgery can treat pathologies for which, until a few years ago, operations were necessary which respected the physiology of the paranasal system to a much lesser extent (Denker-Caldwell-Luc).

Serum levels of tumor associated trypsin inhibitor (TATI) and glomerular filtration rate

TATI (tumor associated trypsin inhibitor) is a low molecular weight protein employed as a tumor marker. To evaluate the role of the kidney in the clearance of TATI, we studied the rat kidney uptake of 125I-TATI. Total body scan demonstrated a high radioactivity in the kidneys of the rats and none in other organs. The relationship between serum TATI and glomerular filtration rate (GFR) was studied in man. For comparison serum beta 2-microglobulin (beta 2M) arid plasma creatinine were also determined. The decrease in GFR was accompanied by an increase in the other parameters. Serum TATI increased in patients with renal failure (GFR < 20 mL/min) 12.4 times with respect to subjects with normal renal function (p < 0.001, non-parametric Mann-Whitney test), beta 2M increased 7.6 times (p < 0.001) and creatinine 4.7 times (p < 0.001). The increase in TATI is statistically significant already in patients with GFR 60-40 mL/min (p < 0.005). These results suggest that TATI is handled by the kidney. It is a sensitive marker of reduction in renal function.

Acute exogenous elevation of plasma free fatty acids does not influence the plasma magnesium concentration

OBJECTIVE

Plasma non-esterified (free) fatty acid concentrations rise as a consequence of stimulated endogenous lipolysis and are inversely related to the plasma magnesium concentration when plasma adrenaline concentration is increased. The aim of the study was to test whether high plasma non-esterified fatty acid concentration after infusion of non-esterified fatty acids decreases plasma magnesium concentration.

METHODS

Twelve healthy subjects received 500 ml Intralipid or saline in a randomised, cross-over, double-blind design. Infusion of Intralipid results in an isolated elevation of plasma non-esterified fatty acid concentration. Plasma magnesium concentration was determined at baseline and every 30 minutes; plasma non-esterified fatty acid and triglyceride concentrations at baseline and after 120 minutes.

RESULTS

Initial plasma magnesium, non-esterified fatty acid, and triglyceride concentrations were similar in both groups. A significant increase in plasma non-esterified fatty acids (2.42 +/- 0.96 mmol/l vs 0.58 +/- 0.23 mmol/l, p = 0.00013) and triglyceride (median and 95th percentile 5.36 (7.35) mmol/l vs 1.18 (1.92) mmol/l, p = 0.003) concentrations was seen with Intralipid. Plasma magnesium concentration increased significantly after Intralipid (0.89 +/- 0.09 mmol/l vs 0.81 +/- 0.06 mmol/l, p = 0.007). No significant changes were seen with saline. A positive association was found between the change in plasma magnesium and triglyceride concentrations (r = 0.85, p = 0.001).

CONCLUSION

Acute infusion of non-esterified fatty acids from an exogenous source does not result in a fall in plasma magnesium concentration, indicating that the circulating non-esterified fatty acids play no part in a decrease in plasma magnesium concentration. The high circulating non-esterified fatty acid levels and the fall in plasma magnesium concentration are both a consequence of intracellular lipolysis.

Experimental Electron-Density Study of 4-Cyanoimidazolium-5-olate at 120 K

This paper presents an analysis of the electron density in 4-cyanoimidazolium-5-olate, determined by the rigid pseudoatom model from accurate X-ray data measured at 120 K. A comparison of the electrostatic potential between experiment and theory is given for the isolated molecule. The results confirm the typical mesoionic electron distribution of the title compound and the presence of three hydrogen bonds in the crystal structure. The atomic charges and molecular dipole moment derived from the ab initio Hartree–Fock method are close to those obtained from the multipole model, which includes the kappa radial parameters. Electrostatic energies are also calculated for hydrogen bonding and molecular stacking interactions.