[Is the correlation between adequate dialysis in peritoneal dialysis and nutritional parameters mathematical or biological? Influence of residual renal function and comorbidity]

The relationship between urea Kt/V and nPCR (nPNA) is partly due to a mathematical coupling and greatly depends on the residual renal function (RRF). On the other hand, albumin could be just a comorbidity marker. Our objective in this study was to verify whether dialysis dose in peritoneal dialysis (PD) is biologically related to the nutritional state measured by the mean values of several parameters not mathematically related while analyzing the influence of RRF and comorbidity (C). 101 stable PD patients, 60M and 41F with a mean age of 59.3 +/- 14.3 years, were studied and followed up every six months for a mean time of 35.8 +/- 22.3 months (8-112). The variables studied were initial comorbidity, plasma albumin, normalized protein nitrogen appearance (nPNA), lean body weight % (LBW%) and fat-free mass index (FFMI) derived from creatinine, and RRF. In every study (n = 471) the 24 hours dialysate and urine volumes were collected and the total (T), dialytic (P) and renal (R) urea KT/V and normalized creatinine clearance (CCR) were determined and compared with the nutritional parameters. When starting PD 48 patients (47.5%) had some C and 34 (33.7%) were already anuric. The correlations of nPNA with T-KT/V and T-CCR (n = 101) were r = 0.67 and 0.50 (p < 0.0005) while the correlations of LBW% with T-KT/V and T-CCR were r = 0.36 and 0.40 (p < 0.0005) respectively. The correlations of albumin with T, P and R KT/V and CCR did not reach significance. The nutritional state was better in patients with a higher RRF and albumin showed significant differences when related to morbidity. KT/V and CCR correlations with nutritional variables not mathematically related verify the hypothesis that dialysis dose is biologically associated with the nutritional state.

TNF-alpha dependent production of inducible nitric oxide is involved in PGE(1) protection against acute liver injury

BACKGROUND

Tumour necrosis factor alpha (TNF-alpha) and nitric oxide modulate damage in several experimental models of liver injury. We have previously shown that protection against D-galactosamine (D-GalN) induced liver injury by prostaglandin E(1) (PGE(1)) was accompanied by an increase in TNF-alpha and nitrite/nitrate in serum.

AIMS

The aim of the present study was to evaluate the role of TNF-alpha and nitric oxide during protection by PGE(1) of liver damage induced by D-GalN.

METHODS

Liver injury was induced in male Wistar rats by intraperitoneal injection of 1 g/kg of D-GalN. PGE(1) was administered 30 minutes before D-GalN. Inducible nitric oxide synthase (iNOS) was inhibited by methylisothiourea (MT), and TNF-alpha concentration in serum was lowered by administration of anti-TNF-alpha antibodies. Liver injury was evaluated by alanine aminotransferase activity in serum, and histological examination and DNA fragmentation in liver. TNF-alpha and nitrite/nitrate concentrations were determined in serum. Expression of TNF-alpha and iNOS was also assessed in liver sections.

RESULTS

PGE(1) decreased liver injury and increased TNF-alpha and nitrite/nitrate concentrations in serum of rats treated with D-GalN. PGE(1) protection was related to enhanced expression of TNF-alpha and iNOS in hepatocytes. Administration of anti-TNF-alpha antibodies or MT blocked the protection by PGE(1) of liver injury induced by D-GalN.

CONCLUSIONS

This study suggests that prior administration of PGE(1) to D-GalN treated animals enhanced expression of TNF-alpha and iNOS in hepatocytes, and that this was causally related to protection by PGE(1) against D-GalN induced liver injury.

Renal Doppler sonographic and histologic findings in post-transplant primary cytomegalovirus disease

Cytomegalovirus (CMV) infections frequently develop in renal transplant patients. The transplanted kidney may be not only the source of infection but also the target for it. We report a case of primary CMV infection in a seronegative patient who received a graft from a seropositive cadaveric donor. The onset of CMV was clinically apparent on post-transplant day 22. Interestingly, soon after transplantation, the patient developed a long-lasting graft dysfunction episode for which diffuse endothelial-cell swelling was the most relevant finding at biopsy. On sonography, renal graft vascular impedance deteriorated and improved repeatedly during the follow-up period. We postulate that the patient had CMV-induced immunogenic-mediated endothelial-cell injury.

Synthesis of a series of 3-cyanopropionamides and 4-imino-gamma-butyrolactams and evaluation of their function as modulators of multidrug resistance

The synthesis of the 3-cyanopropionamides 3a and 3b, of the 2,2-dimethyl-3-cyanopropionamides 4a-4c and of the 4-imino-gamma-butyrolactams 5a and 5b (cyclic functional isomers of 3-cyanopropionamides) is described. The amides 3a and 3b were obtained by aminolysis of the corresponding acid chlorides, which are accessible via hydrolysis of the ethyl esters to the acids. This methodology was not used for the synthesis of the amides 4a-4c owing to steric hindrance to hydrolysis in the corresponding ethyl esters. These nonreactive esters, accessible by alkylation of 1-cyano carbanions with ethyl bromodimethylacetate, could be directly converted into the amides 4a-4c by aminolysis with the lithium amide of 3,4-dimethoxy-N-methylphenethylamine. Instead of open-chain amides, the lactams 5a and 5b are obtained when the lithium amide of 3,4-dimethoxyphenethylamine (i.e., of a primary rather than secondary amine) is used for the aminolysis. The synthesized compounds were tested for their ability to decrease the resistance to vincristine in a multidrug-resistant subline of murine leukemic lymphoblasts that are 300-fold resistant to the antiproliferative drug. The amides 4a and 4c, and lactam 5a, all of which have a highly branched carbon backbone, were active. Lactam 5a reduced the vincristine resistance by 90% at a 2-microM concentration.

Binding of Escherichia coli lipopolysaccharide to fasciculata-reticularis and glomerulosa cells evaluated by flow cytometry

Binding of Escherichia coli lipopolysaccharide (LPS) to the two cell types of the adrenal cortex: fasciculata-reticularis and glomerulosa cells has been studied by flow cytometry and using fluorescein-labeled lipopolysaccharide (FITC-LPS). The binding characteristics were different in relation to time course and number of binding sites. Both fasciculata-reticularis and glomerulosa cells bound LPS in a specific and saturable process. Fasciculata-reticularis cells showed a higher affinity for LPS binding than glomerulosa cells as deduced from Hill plots. Unlabeled LPS decreased FITC-LPS binding in both fasciculata-reticularis and glomerulosa cells, suggesting competition of both ligands for a limited number of binding sites. Lipid A seemed not to be essential for binding of LPS to fasciculata-reticularis cells. However, serum constituents inhibited FITC-LPS binding to both cell types, possibly due to cell interaction with HDL. The exposure of cells to LPS during cell culture did not modify the number of binding sites, but revealed cell size and surfaces structure changes.

Improved capillary electrophoresis method for measuring rare-earth elements in synthetic geochemical standards

An improved capillary electrophoresis (CE) method for quantifying rare-earth elements (REEs) in synthetic geochemical standards was developed. Synthetic standard solutions were obtained from high purity metal oxides. The separation of REE total group (lanthanum to lutetium) was defined as a primary objective. Special attention was also focused on the optimized separation of europium (Eu) and gadolinium (Gd) because in earlier applications they presented overlapping problems. Their separation and quantitative determinations are essential for geological applications. For the rapid separation of REEs in synthetic geochemical standards, the temperature of the separation device was optimized. An analysis temperature of 15 degrees C enabled both the rapid separation of REEs within 2 min and the overlapping problem of Eu-Gd to be resolved. The detection limits (<0.1 ng) and precision estimates (generally better than 5%) were found to be satisfactory for most geological applications.

Kinetic modelling of the synthesis of 2-hydroxy-5-hexenyl 2-chlorobutyrate ester by an immobilised lipase

An esterification process was developed for the direct synthesis of 2-hydroxy-5-hexenyl 2-chlorobutyrate ester from 2-chlorobutyric acid by using the epoxide 1,2-epoxy-5-hexene and Mucor miehei immobilised lipase as the biocatalyst in a batch reactor. The effect of temperature, catalyst concentration, and substrate and product concentration has been studied. An ordered Bi Uni enzymatic mechanism with competitive inhibition by the epoxide and acid has been proposed. The corresponding kinetic parameters were calculated by non-linear regression. Activation energy shows a value of 8.04kcal/mol. The thermodynamic parameters of the process, enthalpy and entropy, were 15.4kcal/mol and 45cal/mol, respectively.

Alpha v integrin antagonists induce the disassembly of focal contacts in melanoma cells

In recent years, several antagonists of alpha(v)beta3 have been used to develop therapeutic approaches to the treatment of melanoma neoplasia. We studied the effects of anti-alpha(v)-integrin-blocking antibodies on attached M21 melanoma cells, the cellular distribution of alpha(v)-integrin and the molecular organization of focal structures. Anti-alpha(v)-integrin-blocking antibodies 17E6 and LM609, and an anti-alpha(v)beta3-integrin antagonist peptide cRGD 85189 induced detachment of M21 melanoma cells cultured for 24 hours on various substrates. cRGD was the most effective antagonist, reducing the number of adherent cells by 80%, while 17E6 reduced adhesion by only 30%. Light- and electron microscopy revealed attached cells with a flat shape and well-formed actin cytoskeleton. After treatment, cells became rounded and detached from the culture dish. alpha(v)-Integrins and focal-contact proteins were observed at adhesion sites in focal structures by immunocytochemistry. After treatment, however, cell rounding was accompanied by disorganization of the actin filaments and redistribution of alpha(v)-integrins and most of the focal proteins studied, except vinculin and tensin. Our results indicate that treatment of M21 melanoma cells with a(v)-integrin antagonists disrupts the actin cytoskeleton, redistributes a(v)-integrin and induces molecular disassembly of focal contacts.

Allogeneic peripheral stem cell transplantation in a case of hereditary sideroblastic anaemia

We report on a case of pyridoxine refractory hereditary sideroblastic anaemia (HSA) in a 19-year-old man who underwent peripheral blood stem cell transplantation (PBSCT) from his HLA-identical brother. By using short tandem repeat polymorphism, 100% donor cells were observed in peripheral blood on day +21; bone marrow showed mixed chimaerism from day +21 to day +221, when 100% cells of donor origin were observed. The patient developed extensive chronic graft-versus-host disease with favourable response to treatment. When the haemoglobin range was normal, a programme of phlebotomies reduced serum ferritin levels. Three years after transplantation, the patient has an ECOG rating of 0, with completely normal haemoglobin values (15 g/dl). To our knowledge, this is the first PBSCT reported in a case of hereditary sideroblastic anaemia.

Exposure to air pollution is associated with lung hyperinflation in healthy children and adolescents in Southwest Mexico City: a pilot study

Air pollution produces adverse health effects. The consequences of lifelong daily exposures to atmospheric pollutants upon the respiratory apparatus of healthy children are of considerable clinical importance. We investigated the association between exposure to a highly polluted urban environment with a complex mixture of air pollutants-ozone and particulate matter the predominant ones-and chest x-ray abnormalities in 59 healthy Mexican children who are lifelong residents of Southwest Metropolitan Mexico City (SWMMC), with a negative history of tobacco exposure and respiratory illnesses. Their clinical results and x-ray findings were compared to those of 19 Mexican control children, residents of a low-pollution area, with a similar negative history of tobacco exposure and respiratory illnesses. Ozone concentrations in SWMMC exceeded the U.S. Environmental Protection Agency (U.S. EPA) National Ambient Air Quality Standard (NAAQS) for O(3): 0.08 ppm as 1-h maximal concentration, not to be exceeded more than 4 times a year, on 71% of days in 1986 and 95% in 1997, with values as high as 0.48 ppm. Ozone maximal peaks are usually recorded between 2 and 5 pm coinciding with children's outdoor physical activities. Children in the control group reported no upper or lower respiratory symptomatology. Every SWMMC child complained of upper and/or lower respiratory symptoms, including epistaxis, nasal dryness and crusting, cough, shortness of breath, and chest discomfort. Children aged 7-13 yr had the most symptomatology, while 5- to 6-year olds and adolescents with the lowest number of statistically significant outdoor exposure hours had less respiratory symptoms. Bilateral symmetric mild lung hyperinflation was significantly associated with exposure to the SWMMC atmosphere (p = .0004). Chronic and sustained inhalation of a complex mixture of air pollutants, including ozone and particulate matter (PM), is associated with lung hyperinflation, suggestive of small airway disease, in a population of clinically healthy children and adolescents. Small airways are a target of air pollutants in SWMMC children, with ozone and PM being most likely responsible, based on experimental animal, controlled-chamber, and epidemiological data available. Our main concern is the potential likelihood for the development of chronic lung disease in this highly exposed population.

In vivo estrogen bioactivities and in vitro estrogen receptor binding and transcriptional activities of anticoagulant synthetic 17beta-aminoestrogens

Estrogenic activities of the two 17beta-aminoestrogen (AE) derivatives, prolame and butolame, were studied upon coagulation, serum luteinizing hormone (LH) and uterine weight, including endometrial morphology in castrated female rats. We have also investigated the ability of these two compounds, as well as another AE pentolame, to activate transcription through the estrogen receptor alpha (ERalpha) and the estrogen receptor beta (ERbeta). Administration of prolame and butolame to castrated animals increased significantly (P < 0.01) the mean clotting time when compared with that obtained in the group of control animals. Butolame was a more potent anticoagulant than prolame (P < 0.01), as judged by their corresponding IC(50) (5.4 +/- 0.65 and 66.6 +/- 2.57 micro;g/animal, respectively). In contrast, estradiol significantly shortened blood clotting times (P < 0.005). Both prolame and butolame caused a significant inhibition of serum LH levels (EC(50) 8.10 +/- 0.79 and 17 +/- 64 microg/animal, respectively), and restored castration-induced reduction in uterine weight of ovariectomized rats (EC(50) 4.14 +/- 1.57 and 17.0 +/- 1.78 microg/animal, respectively). In terms of the effects of prolame, butolame and pentolame in transient transfection assays, all the three AE activated ER dependent reporter gene expression, however, only at high concentrations. Prolame had the highest activity followed by butolame and pentolame. Induction of transcription by these compounds was preferentially mediated through the ERalpha, especially in the case of pentolame where little, if any, activation occurred through the ERbeta. None of the compounds showed antagonistic activities through either ER subtype. The overall data suggest that modifications in the structure and length of the amino-alcohol side-chain at C-17 might have an impact on the affinity and estrogenic intrinsic properties of AE at the level of diverse target tissues.

[Early prognosis in chronic subdural hematomas. Multivariate analysis of 137 cases]

INTRODUCTION

In the literature there is evidence relating different factors such as age and preoperative clinical condition with prognosis in patients treated surgically for chronic subdural haematoma.

OBJECTIVE

To clarify and quantify the magnitude of the factors which determine early prognosis (during hospital admission) of these patients.

PATIENTS AND METHODS

We made a prospective study of 137 patients who had been operated on in our centre and found the relationship between different clinical and therapeutic variables with the clinical course and morbidity-mortality by means of multivariate and survival analysis.

RESULTS

A high Markwalder functional score (3-4) is an independent factor of poor prognosis (OR = 13.15; CI 95% 6.1-28.4; p = 0.01), as is the presence of a coexisting coagulopathy (OR = 27.2; CI 95% 9.3-79.5; p = 0.01). Advanced age tended to increase the risk (OR = 1.104) but did not reach statistical significance (p = 0.0654). A multivariate logistic model, which included the functional score and presence of coagulopathy, correctly classified 94.7% of the cases studied. Analysis of survival showed two groups with different early mortality as a function of the Markwalder score (high: 3-4 and low: 0-1-2), which could be differentiated statistically (Log-Rank chi squared test: 3.95; p = 0.0468).

CONCLUSIONS

The preoperative clinical state classified by functional scores and the presence of underlying coagulopathy are the main prognostic factors in chronic subdural haematoma during hospital admission. Advanced age is probably not in itself an independent factor for bad prognosis.

[Intraoperative awakening: report of a case in pediatric surgery]

Intraoperatory awakening or awareness can be defined as recovering of conscience during general anesthesia. We report such a case happened in a 11 year-old boy during a hypospadias repair. After anesthetic education he related intraoperatory conscience without pain, anxiety, displeasing symptoms or long-term psychoconductal distress. We remark fisiopathology, diagnostic and preventive aspects of this rare event in pediatric surgery.

Cytotoxic constituents of the roots of Ekmanianthe longiflora

Bioactivity-directed fractionation of the CHCl(3) extract of the roots of Ekmanianthe longiflora resulted in the isolation of three new natural products, (2R,3R,4R)-3,4-dihydro-3, 4-dihydroxy-2-(3-methyl-2-butenyl)-1(2H)-naphthalenone (1), (2S,3R, 4R)-3,4-dihydro-3, 4-dihydroxy-2-(3-methyl-2-butenyl)-1(2H)-naphthalenone (2), and (2R, 3aR,9R,9aR)-9-hydroxy-2-(1-hydroxy-1-methylethyl)-2,3,3a,4,9 , 9a-hexahydro-naphtho[2,3-b]furan-4-one (3), together with the known compounds 2-(1-hydroxyethyl)naphtho[2,3-b]furan-4,9-quinone (4), 2-acetylnaphtho[2,3-b]furan-4,9-quinone (5), dehydro-iso-alpha-lapachone (6), alpha-lapachone (7), catalponol, and epi-catalponol. The structures of 1-3 were determined using a combination of NMR spectroscopic techniques, and the absolute configurations of compounds 1 and 2 were obtained using Mosher ester methodology. Compounds 4-6 showed significant cytotoxicity in a panel of human cancer cells. alpha-Lapachone (7) exhibited only marginal activity, and catalponol and epi-catalponol were inactive in this regard. When tested at 72 mg/kg/injection in an in vivo mouse P-388 leukemia system, compound 4 was inactive (110% T/C).

Extended-spectrum beta-lactamases in clinical isolates of enterobacteria in Mexico

Resistance to extended-spectrum cephalosporins within members of the family Enterobacteriaceae occurs virtually world-wide. Nevertheless, nothing was known about this problem among isolates from Mexico. To address this issue, we studied oximino-cephalosporin resistant isolates of Klebsiella pneumoniae (13), Escherichia coli (7), and Enterobacter cloacae (23) recovered from patients in Mexico City hospitals during 1990 to 1992. In the presence of clavulanic acid, these strains increased susceptibility to cefotaxime and ceftazidime (MIC90 64 and >256 microg/ml, respectively). The ability of these isolates to transfer resistance to both antibiotics by conjugation was most successfully demonstrated by K. pneumoniae. In all the clinical isolates tested, the largest plasmid coded for the extended-spectrum beta-lactamases (ESBL). Characteristics of pI, by isoelectric focusing (IEF)/bioassay and DNA hybridization with specific probes of TEM and SHV, indicated that in most of the clinical isolates and all transconjugates, the most frequent beta-lactamase coded were SHV-derived (20 strains as 41% of isolates) and a plasmid-encoded beta-lactamase (12 strains as 25% of isolates) (with a pI of >8.2), which is not related to TEM/SHV. Apparently, isolates from Mexico show characteristics similar to isolates from other geographic areas. The type of beta-lactamases coded in these resistant isolates is documented for the first time in Mexico.

High-resolution imaging of antibodies by tapping-mode atomic force microscopy: attractive and repulsive tip-sample interaction regimes

A force microscope operated with an amplitude modulation feedback (usually known as tapping-mode atomic force microscope) has two tip-sample interaction regimes, attractive and repulsive. We have studied the performance of those regimes to imaging single antibody molecules. The attractive interaction regime allows determination of the basic morphologies of the antibodies on the support. More importantly, this regime is able to resolve the characteristic Y-shaped domain structure of antibodies and the hinge region between domains. Imaging in the repulsive interaction regime is associated with the irreversible deformation of the molecules. This causes a significant loss in resolution and contrast. Two major physical differences distinguish the repulsive interaction regime from the attractive interaction regime: the existence of tip-sample contact and the strength of the forces involved.

High-resolution imaging of antibodies by tapping-mode atomic force microscopy: attractive and repulsive tip-sample interaction regimes

A force microscope operated with an amplitude modulation feedback (usually known as tapping-mode atomic force microscope) has two tip-sample interaction regimes, attractive and repulsive. We have studied the performance of those regimes to imaging single antibody molecules. The attractive interaction regime allows determination of the basic morphologies of the antibodies on the support. More importantly, this regime is able to resolve the characteristic Y-shaped domain structure of antibodies and the hinge region between domains. Imaging in the repulsive interaction regime is associated with the irreversible deformation of the molecules. This causes a significant loss in resolution and contrast. Two major physical differences distinguish the repulsive interaction regime from the attractive interaction regime: the existence of tip-sample contact and the strength of the forces involved.

[Neurophysiological clinical study of 70 patients with type 2 spinocerebellar ataxia]

INTRODUCTION

The prevalence of hereditary ataxia in Holguín, Cuba, is 43 per 100,000 inhabitants, but in some regions reaches 503 per 100,000 inhabitants, a figure never previously recorded in the international literature.

OBJECTIVES

To evaluate the part played by non-cerebellar structures and vias in causing some of the clinical signs of the disorder by means of clinico-electro physiological correlation.

PATIENTS AND METHODS

A neurological examination, peripheral nerve conduction studies and somato-sensorial evoked potentials of the median and posterior tibial nerves were done in 70 patients with type 2 spinocerebellar ataxia.

RESULTS

The commonest clinical signs were ataxia on walking, dysarthria, dysmetria and adiadochokinesia. Correlation analysis showed that the variable most significantly correlated with the degree of ataxia and Romberg's sign was latency of the P40 component, whilst tendon reflexes were best correlated with H reflex latency. However, the duration of the disease was not found to have statistical correlation.

CONCLUSIONS

These results suggest that degeneration of long peripheral nerves and sensory paths contributes to the degree of ataxia and other clinical signs. At present no correlation has been found between the duration of the illness and increasing electrophysiological changes, and therefore seems not to have a major effect on neurodegenerative mechanisms.

Neuregulin found in cultured-sciatic nerve conditioned medium causes neuronal differentiation of PC12 cells

The present work deals with the search and identification of the molecule or combination of molecules, present in a medium conditioned by cultured rat-sciatic nerves (CM), able to cause neuronal differentiation of PC12 cells. The molecular mass range of the active fraction, as well as the thermostability and heparin affinity of the active component found in previous work, all characteristics shared with neuregulin (NRG) family members, led us to search for a NRG protein in the CM. Nerves were previously cultured for 8 days and the CM collected every 24 h, the following 3 days. The CM was concentrated (30,000 NMWL) and fractionated by quaternary ammonium chromatography and Cibacron blue affinity chromatography. The most active fraction B1.2 was further characterized by heparin affinity chromatography, size exclusion HPLC, Western blotting and immunoprecipitation. Results reveal abundance of NRG mRNA in the cultured nerves, presence of a 54 kDa NRG protein in the CM that increases along fractionation, and progressive diminution of fraction B1.2 differentiation activity on PC12 cells by gradual removal of the NRG protein by immunoprecipitation. The abundance of Schwann cells and the lack of axons in the cultured nerves suggest Schwann cells as the main NRG source, to which fibroblasts and perineurial cells might contribute.

Titanium levels in rats implanted with Ti6Al4V treated samples in the absence of wear

The effect of implantation time and implant nitriding on titanium ion concentration in several tissues of rats carrying Ti6Al4V implants was studied by means of inductively coupled plasma-mass spectroscopy (ICP-MS). Histological studies were also performed in order to check for tissue degeneration due to the Ti6Al4V implantation. The animals were divided into four groups: one received Ti6Al4V implants, the second received nitrided Ti6Al4V implants, the third group received nitrided and descaled Ti6Al4V implants and the last one was the control group. Half the animals of the implanted groups received the Ti6Al4V implant for 30 days, while the other half received the implant for 120 days. Spleen, muscle, kidney, lung, brain and bone samples were retrieved from these rats as well as the control group. Ion concentration measures did not show significant differences between control and implanted rats for the studied period of time, although histological studies showed minor differences, especially on liver tissue samples.

Serial pulsatility index measurements in renal grafts before, during, and after episodes of urinary obstruction

The usefulness of pulsatility index determinations for the diagnosis of obstructive collecting system dilatation was investigated in 10 renal transplant patients whose grafts developed urinary obstruction from different causes. For this purpose we compared pulsatility index values obtained (1) before the ultrasonographic detection of obstruction or baseline study, (2) 1 day before surgical repair, and (3) within 2 weeks after surgery. In 7 of 10 obstructed grafts, the pulsatility index values were increased only mildly to moderately preoperatively. In the remaining three grafts, a mild decrease in pulsatility index was observed in spite of severe collecting system dilatation. Changes in pulsatility index were not statistically significant. Impedance measurements appeared not to be useful for diagnosing obstructive collecting system dilatation.

Estrogen stimulates neuronal nitric oxide synthase protein expression in human neutrophils

Recent studies have postulated the contribution of nitric oxide (NO) released by the endothelium to the beneficial effects of estrogen. Despite a neuronal-type NO synthase (nNOS) described in neutrophils, less is known about the effect of estrogen in these cells. The aim of the present study was to analyze the expression of nNOS protein in human neutrophils under different estrogenic conditions. We first analyzed nNOS expression in neutrophils obtained from premenopausal women. During the first 2 days of the follicular phase (low circulating estrogen concentrations), nNOS expression in neutrophils was reduced with respect to that found in neutrophils obtained from the same donors during the ovulatory phase (high circulating estrogen concentrations). Moreover, the expression of nNOS protein in neutrophils obtained from postmenopausal women after transdermal estrogen therapy was markedly enhanced with respect to that observed before the treatment. In vitro incubation of neutrophils derived from men for 6 hours with 17beta-estradiol (10(-10) to 10(-8) mol/L) upregulated the expression of nNOS protein. The 17beta-estradiol receptor antagonists, tamoxifen (10(-8) mol/L) and ICI 182780 (10(-8) mol/L), inhibited the upregulation of nNOS protein induced by 17beta-estradiol. The putative functional implication was denoted by a reduced expression of the CD18 antigen on the surface of 17beta-estradiol-incubated neutrophils, which was accompanied by a decreased adhesive capacity. Both effects were prevented by an NO antagonist. In conclusion, the in vivo levels of circulating estrogen concentrations seem to be associated with the level of nNOS protein expression in neutrophils from women. Moreover, low doses of 17beta-estradiol upregulate nNOS protein expression in neutrophils from men. The increased ability of 17beta-estradiol-incubated neutrophils derived from men to produce NO reduced their adhesive properties.

Nonpigmented fixed drug eruption caused by paracetamol

Fixed drug eruption from paracetamol is not rare but no cases of nonpigmented fixed drug eruption caused by paracetamol have been previously described. We present the case of a woman who developed a nonpigmented fixed drug eruption following administration of paracetamol. Patch tests performed on affected and unaffected skin with paracetamol were negative. The diagnosis was made by a double-blind oral challenge with paracetamol. The patient tolerated aspirin.

Characterization of the oligosaccharides assembled on the Pichia pastoris-expressed recombinant aspartic protease

Aspartic protease, widely used as a milk-coagulating agent in industrial cheese production, contains three potential N-glycosylation sites. In this study, we report the characterization of N-linked oligosaccharides on recombinant aspartic protease secreted from the methylotrophic yeast Pichia pastoris using a combination of mass spectrometric, 2D chromatographic, chemical and enzymatic methods. The carbohydrates from site I (Asn79) were found to range from Man6-17GlcNAc2 with 50% bearing a phospho-diester-motif, site II (Asn113) was not occupied and site III (Asn188) contained mostly uncharged species ranging from Man-13GlcNAc2. These charged groups are not affecting the transport through the secretion pathway of the recombinant glycoprotein. Changes from a molasses-based medium to a minimal salts-based medium led to a clear reduction of the degree of phosphorylation of the N-glycan population.

Modeling of air pollution and its relationship with mortality and morbidity in Madrid, Spain

OBJECTIVE

Evaluation of the association between air pollution and mortality and morbidity is becoming ever more complex owing to changes in inner-city air pollution, marked by decreasing values for all main pollutants save those associated with traffic. This has led to the need for the study of new epidemiological scenarios in which most pollutants are below guideline values. Nonetheless, the health effects are significant.

METHODS

This report presents the results of a statistically based model for real-time forecasting of mortality and morbidity in Madrid, with meteorological and pollution series serving as inputs.

RESULTS AND CONCLUSIONS

Not only did the models perform well with correlation coefficients between predicted and observed values (r = 0.683 for mortality, r = 0.681 for morbidity), but they enabled quantification of the impact of air pollution on mortality and morbidity (with increases ranging from 1. 8% to 12% for mortality and from 2.3% to 18% for morbidity for a 25-microg/m(3) increase in pollutants). Moreover, attention should be drawn to the observation that the model proved to be easy to implement and operate on a routine basis.

Genetic analysis of apomixis in Citrus and Poncirus by molecular markers

Propagation of citrus rootstocks depends upon the production of clonal plants from nucellar seedlings. This makes apomixis one of the host important traits in breeding programs for citrus rootstocks. The genetic control of apomixis was studied in a 50-tree progeny derived from the cross C. volkameriana×P. trifoliata using 69 molecular markers and bulked segregant analysis. The proportion of nucellar seedlings was estimated by isoenzymatic analysis of 25 seedlings per tree for 2 consecutive years. The type of embryony (polyembryonic versus monoembryonic seeds) was also determined for fruit-yielding trees. Separate genetic maps for each parental species were developed. The integration and comparison of these maps could be accomplished using common multiallelic segregant loci. Differences in gene synteny between the two species-specific genetic maps were shown. Important distortions in the segregation of markers at several genomic regions, some of them also involving differences in the C-methylation pattern, have been observed, especially for the pollen parent. Analysis of quantitative trait loci (QTLs) revealed the presence of six genomic positions (two in P. trifoliata and four in C. volkameriana) contributing individually up to 24% of the total variation for apomixis. Within the same species, QTLs with positive and negative allele effects were present, even in the same linkage group. One of the markers associated to apomixis (Apo2) is also associated to embryony type. Therefore, the genetic control of apomictic reproduction found in citrus (nucellar embryony) is quite complex compared to what has been reported for gametophytic apomixis. Molecular markers linked to QTLs governing apomixis will be useful to assist selection of future apomictic rootstocks for citrus varieties.

Calcium and reactive oxygen species as messengers in endotoxin action on adrenocortical cells

The effect of Escherichia coli 0111:B4 endotoxin (lipopolysaccharide, LPS) on the intracellular Ca2+ and reactive oxygen metabolite content of both rat isolated fasciculata-reticularis and glomerulosa cells was evaluated by flow cytometry to know the role of these mechanisms in the initiation of cell injury produced by LPS on adrenocortical cells during endotoxic shock. A rapid increase of intracellular calcium was induced by endotoxin in both cell types. In fasciculata-reticularis cells, this [Ca2+]i increase was mainly due to an important mobilization of intracellular stores. Dose-dependent increases in [Ca2+]i were also observed when both cell types were incubated with LPS for 20 min in the presence of extracellular calcium. This treatment abolished the increase in intracellular calcium induced by ACTH and angiotensin II. On the other hand, the endotoxin produced a fast and dose-dependent increase in reactive oxygen species in both cell types, higher in glomerulosa than in fasciculata-reticularis cells. LPS-pretreated cells showed more susceptibility to the oxidative stress induced by Fe2+. These results can be related to functional alterations previously described showing the involvement of calcium and reactive oxygen species as messengers in the endotoxin action on adrenocortical cells.

Syndecan-2 induces filopodia by active cdc42Hs

The syndecans, a family of transmembrane heparan sulfate proteoglycans, are ubiquitous molecules whose intracellular function is still unknown. To examine the function of syndecan-2, one of the most abundant heparan sulfate proteoglycan in fibroblasts, we performed transfection studies in COS-1 and Swiss 3T3 cells. Endogenous syndecan-2 colocalized with F-actin in cortical structures. Overexpression of full-length syndecan-2 induced the formation of long filopodia-like structures. These changes correlated with a rearrangement of the actin cytoskeleton, which strongly colocalized with syndecan-2. Overexpression of syndecan-2 lacking the extracellular domain increased the number of microspikes on the cell surface but failed to induce filopodia. Addition of heparin blocked the effect of full-length syndecan-2, suggesting that heparan sulfate chains in the extracellular domain are necessary to induce filopodia. Coexpression of cdc42Hs negative-dominant N17 blocked syndecan-2-induced filopodia and cdc42Hs positive-dominant V12 had a synergic effect. This indicates that active cdc42Hs is necessary for syndecan-2 induction of filopodia. These results provide a link between syndecan-2, actin cytoskeleton, and cdc42Hs.

Hypoglycaemic activity of four plants used in Chilean popular medicine

The hypoglycaemic activity of a 20% dried leaf infusion of Bauhinia candicans Benth. (Leguminosae), Galega officinalis L. (Leguminosae), Morus alba L. (Moraceae) and Rubus ulmifolius Schott. (Rosaceae), used for diabetes in Chilean popular medicine, was evaluated in alloxan and streptozotocin induced hyperglycaemic rats. In normal rats the different infusions did not modify significantly the glycaemia in the period studied, but in diabetic rats different results were observed, depending on the diabetogenic drug used. B. candicans and R. ulmifolius infusions elicited remarkable hypoglycaemic effects in both experimental models. B. candicans presented a greater decrease of glycaemia in alloxan diabetic rats (39%) and R. ulmifolius showed a similar activity in both alloxan and streptozotocin diabetic rats (28% and 29%). Activity-guided fractionation of R. ulmifolius showed that petroleum ether extracts elicited a marked hypoglycaemic effect (35%) in the streptozotocin induced model.

Effect of losartan on human platelet activation

OBJECTIVE

Previous studies have demonstrated that losartan can block the thromboxane A2 receptor on the vascular wall. The aim of the present study was to assess the effect of losartan on human platelet activation.

METHODS

Platelets were obtained from 15 healthy men, aged 26-40 years. Platelet activation was measured by changes in the light transmission of platelet-rich plasma stimulated by the thromboxane A2 analog U46619 (5 x 10(-6) mol/l) or ADP (10(-5) mol/l).

RESULTS

U46619-stimulated platelet aggregation was significantly inhibited by losartan in a dose-dependent manner. Only a high dose of EXP 3174 (5 x 10(-5) mol/l), the in vivo active metabolite of losartan, was able to attenuate U46619-induced platelet activation. Captopril, an angiotensin I converting inhibitor, failed to modify U46619-induced platelet aggregation. Furthermore, the binding of [3H]-U46619 to platelets was competitively inhibited by losartan, whereas only a high dose of EXP 3174 reduced the binding of [3H]-U46619. Captopril failed to modify the binding of [3H]-U46619 to platelets. Losartan also reduced the platelet activation induced by ADP (10(-5) mol/l), a platelet agonist partially dependent on thromboxane A2. In addition, when thromboxane A2 generation was blocked by aspirin, ADP-induced platelet aggregation was inhibited to a similar degree to the inhibition induced by losartan. Exogenous angiotensin II did not elicit any modification of either U46619- or ADP-stimulated platelet aggregation.

CONCLUSIONS

Losartan decreased platelet aggregation by a thromboxane A2-dependent mechanism. EXP 3174 was less potent than losartan in reducing thromboxane A2-dependent platelet activation. Captopril and exogenous angiotensin II had no effect on human platelet activation. These results suggest that losartan reduced thromboxane A2-dependent platelet activation independently of its effect on angiotensin II.

Patterns of immunoglobulin E sensitization to chironomids in exposed and unexposed subjects

We present our study of four patients with occupational type I allergy to red midge larvae (group 1) who we compared with seven individuals also sensitized to red midge larvae but who had not apparently been exposed to them (group 2). All patients showed elevated specific IgE against Chironomus thummi, and positive skin prick tests (SPT) and provocation tests with red midge larvae. We carried out SPT with Dermatophagoides pteronyssinus, Acarus siro, shrimp, cockroach and common mosquito (Culex pipiens) and specific serum IgE was also determined. The red midge larvae wheal size was significantly larger in group 1 (x = 149.2 mm2) than in group 2 (x = 18 mm2). Significant differences between levels of IgE anti-C. thummi were also found in group 1 (x = 52.12 kU/l) and in group 2 (x = 1.5 kU/l). The patients in group 2 had high levels of specific IgE against other allergens (D. pteronyssinus, shrimp and/or common mosquito) and had positive SPTs with these allergens, while the patients in group 1 were only sensitized to chironomids. The IgE-immunoblotting profile was quite different in both groups. The patients in group 1 seemed to have IgE against Chi t 1, the main Chironomus allergen, while the patients in group 2 had IgE against several protein bands in Chironomus, mosquito, shrimp and D. pteronyssinus extracts, some of them with equivalent molecular weights. We believe that the patients in group 2 were sensitized to Chironomus as a result of cross-reactivity with other insect or crustacean species.

Influence of different chemical cross-linking treatments on the properties of bovine pericardium and collagen

The use of biological materials in the construction of bioprostheses requires the application of different chemical or physical procedures to improve the mechanical performance of the material without producing any undesirable effects. A number of cross-linking methods have been tested in biological tissues composed mainly of collagen. The basis for most of them is the use of glutaraldehyde (GA), which acts on the Lys or Hyl residues. We have studied the effects of alternative chemical treatments: diphenylphosphorylazide (DPPA) and ethyldimethylaminopropyl carbodiimide (EDAC). Their mechanism of action is based on the activation of the carboxyl groups, which then permits their cross-linking to amino groups. As a control, we employed conventional treatment with GA, applying it to bovine pericardium and collagen membranes removed from bovine pericardium. The analysis of the Lys and Hyl residues showed that DPPA and EDAC produced 50% of the chemical change provoked by GA. This value was even lower in the trials with collagen. In terms of the resistance to collagenase degradation, chemical cross-linking with GA provided much greater protection in both materials (3.81 +/- 3.47 nmol of amino acid/mg dry tissue for pericardium and 4.41 +/- 1.13 nmol of amino acid/mg dry tissue for collagen). Treatment with DPPA also protected pericardium (13.11 +/- 6.57 nmol amino acid/mg dry tissue) although the values for collagen was lower (50.0 +/- 32.4 nmol amino acid/mg dry tissue). Treatment with EDAC was much less protective than the other two chemical reagents (43.28 +/- 17.4 and 55.85 +/- 14.57 nmol amino acid/mg dry tissue for pericardium and collagen, respectively). The degree of tissue calcification after implantation of the chemically treated materials into young rats was considerably greater for GA and DPPA (32.9 +/- 18.8 and 36.3 +/- 13.3 mg g(-1) dry tissue, respectively) than with EDAC (18.0 +/- 7.2 mg g(-1) dry tissue; P < 0.001). After 60 days of implantation, the values for GA and EDAC were higher(124.1 +/- 31.3 and 124.6 +/- 21.0 mg g(-1) dry tissue, respectively) versus 34.6 +/- 19.2 mg g(-1) dry tissue for DPPA. There were no significant differences in collagen levels in samples treated with GA or EDAC after 30 days of implantation, although both groups showed significant differences when compared with DPPA-treated samples (P < 0.001). After 60 days of implantation, there were no significant differences among these three treatments in terms of the calcium accumulated on samples.

Favorable response to intravenous methylprednisolone and cyclophosphamide in children with severe neuropsychiatric lupus

OBJECTIVE

To evaluate the effect of intravenous methylprednisolone (IVMP) and cyclophosphamide (IVCy) in children with severe neuropsychiatric (NP) systemic lupus erythematosus (NPSLE).

METHODS

We studied 7 consecutive pediatric patients with severe NPSLE. All patients were treated initially with IVMP and IVCy followed by monthly IVCy for at least 3 months, and then every 2 and/or 3 months according to clinical response. Prednisone was given at 1-2 mg/kg during the first month. Laboratory studies included routine laboratory tests, antinuclear antibodies, anti-dsDNA, antiphospholipid antibodies, and complement components C3 and C4. Neurodiagnostic studies included cerebrospinal fluid, magnetic resonance imaging, computed tomography scanning, single photon emission computed tomography and electroencephalography.

RESULTS

Three patients had organic brain syndrome with psychosis, 3 had seizures, 1 stroke, 1 cerebral vasculitis, 1 optic neuritis, and 1 transverse myelitis. In 3 of these cases, nervous system involvement was the initial presentation of SLE. Five patients had 2 or more NP manifestations. Most of them were accompanied by general SLE activity. Anticardiolipin antibodies were positive in 3 patients and none was anticoagulated. All patients improved, 6 patients had a complete recovery and 1 patient recovered with minor neurological deficit. All but one improved significantly within the first week of combined IVMP and IVCy. The mean time of follow-up was 37 months (range 8-55). IVCy was well tolerated with minimal side effects.

CONCLUSION

Early aggressive treatment with combined IVMP and IVCy followed by monthly IVCy may be an effective therapy for severe NPSLE in children.

Aspirin inhibits inducible nitric oxide synthase expression and tumour necrosis factor-alpha release by cultured smooth muscle cells

BACKGROUND

Inflammatory related cardiovascular disease, i.e. cardiac allograft rejection, myocarditis, septic shock, are accompanied by cytokine production, which stimulates the expression of inducible nitric oxide (iNOS).

MATERIALS AND METHODS

The aim of the present study was to examine whether anti-inflammatory doses of acetylsalicylic acid (aspirin) could regulate iNOS protein expression in bovine vascular smooth muscle cells (BVSMCs) in culture.

RESULTS

Interleukin 1 beta (IL-1 beta, 0.03 U mL-1) induced nitric oxide release by BVSMCs. Aspirin inhibited nitric oxide release from IL-1 beta-stimulated BVSMCs in a dose-dependent manner. In addition, aspirin significantly inhibited iNOS protein expression in BVSMCs and reduced the translocation of the nuclear factor-kappa B (NF-kappa B). Furthermore, aspirin and the blockade of NO generation by BVSMCs reduced the production of tumour necrosis factor alpha (TNF-alpha) by these cells.

CONCLUSION

High doses of aspirin inhibited iNOS protein expression in BVSMCs and decreased NF-kappa B mobilization. The inhibition of iNOS expression by aspirin was further associated with a reduced ability of BVSMCs to produce TNF-alpha. This study could provide new mechanisms of action for aspirin in the treatment of the inflammation-related cardiovascular diseases.

Anaphylaxis to omeprazole

BACKGROUND

Omeprazole is a non-competitive inhibitor of the parietal cell enzyme H+-K--adenosine triphosphatase. To date, two cases of angioedema and urticaria and two cases of anaphylaxis from omeprazole have been published.

OBJECTIVE

To report a new patient with omeprazole-induced anaphylaxis demonstrated by skin tests and increased serum tryptase levels.

METHODS AND RESULTS

Elevated serum tryptase levels (5.1 U/L) were detected 6 hours after the onset of the anaphylaxis. Skin intradermal tests were positive with omeprazole i.v. (4 mg/mL), omeprazole capsules diluted in saline serum (20 mg/ mL), and lansoprazole (30 mg/mL). Serum specific IgE anti-omeprazole was negative.

CONCLUSIONS

According to the elevated serum tryptase levels and the positive skin test results, anaphylaxis was due to use of omeprazole. We think the adverse reaction to omeprazole was induced by an IgE-mediated hypersensitivity mechanism to omeprazole itself and not to a metabolite. We have also demonstrated crossreactivity, at least by skin tests, between omeprazole and lansoprazole.

[Our experience with the Univent tube]

INTRODUCTION

We describe our experience in managing single lung ventilation (SLP) with the Univent bronchial blocker tube from 1993 to the present.

PATIENTS AND METHOD

Patients were grouped based on the following criteria: use of a double lumen tube as an alternative to SLP (group 1), use of SLP and tracheotomy (group 2), or difficult or dangerous orotracheal intubation (group 3).

RESULTS

The mean age of the 32 patients (22 men and 10 women) studied was 45.7 +/- 12.2 years. Mean weight was 67.9 +/- 13.4 kg. Ten patients were physical status ASA I, 10 were ASA II, 10 were ASA III and 2 were ASA IV. Group 1 contained 28 patients (18 receiving right SLP and 10 receiving left SLP; use of SLP failed to collapse the lung in 4 patients [14.3%]). Group 2 consisted of 5 patients and group 3 contained 11. The Univent tube was used in 4 patients in group 3 who did not require use of SLP but whose intubation was considered difficult and in whom laryngoscopic findings were consistent with a Cormack-Lehane group III classification. The Univent bronchial blocker tube was used as a guide, such that intubation was achieved on the first try. The tube was removed from 3 patients (8%) in the intensive care recovery ward. The remaining 29 tracheas were extubated in the operating room. No side effects attributable to the Univent tube were recorded.

CONCLUSIONS

The advantages and disadvantages of this new tool for the management of SLP mean that it may be useful for specific situations (such as for SLP with difficult intubation or in patients with tracheotomies or aneurysms of the descending thoracic aorta), but that it does not replace conventional methods. We believe that the Univent bronchial blocker tube should be available as part of operating room equipment.