Msx1-Deficient Mice Fail to Form Prosomere 1 Derivatives, Subcommissural Organ, and Posterior Commissure and Develop Hydrocephalus

Msx1 is a regulatory gene involved in epithelio-mesenchymal interactions in limb formation and organogenesis. In the embryonic CNS, the Msx1 gene is expressed along the dorsal midline. Msx1 mutant mice have been obtained by insertion of the nlacZ gene in the Msx1 homeodomain. The most important features of homozygous mutants that we observed were the absence or malformation of the posterior commissure (PC) and of the subcommissural organ (SCO), the collapse of the cerebral aqueduct, and the development of hydrocephalus. Heterozygous mutants developed abnormal PC and reduced SCO, as revealed by specific antibodies against SCO secretory glycoproteins. About one third of the heterozygous mutants also showed hydrocephalus. Other defects displayed by homozygous mutants were ependymal denudation, subventricular cavitations and edema, and underdevelopment of the pineal gland and subfornical organ. Some homozygous mutants developed both SCO and PC, probably as a consequence of genetic redundancy with Msx2. However, these mutants did not show SCO-immunoreactive glycoproteins and displayed obstructive hydrocephalus. This suggests that Msx1 is necessary for the synthesis of SCO glycoproteins, which would then be required for the maintenance of an open aqueduct.

Hepatic lesions in cetaceans stranded in the Canary Islands

This article describes the gross, histopathologic, and ultrastructural findings of the livers of cetaceans stranded on the coast of the Canary Islands between 1992 and 2000. A total of 135 cetaceans were included in the study, among which 25 were common dolphins (Delphinus delphis), 23 Atlantic spotted dolphins (Stenella frontalis), 19 striped dolphins (Stenella coeruleoalba), and 15 other species of dolphins and whales. The most common lesion observed in these animals was a nonspecific chronic reactive hepatitis (47/135), followed by hyaline intracytoplasmic inclusions in hepatocytes (33/135). Parasitic cholangitis was detected in 8/135 animals, whereas hepatic lipidosis was presented in 7/135 animals. The ultrastructure of hyaline hepatocytic cytoplasmic inclusions is described, and possible causes of these inclusions are discussed.

[Distribution of capsular types and antimicrobial susceptibility of Streptococcus agalactiae causing infections in Argentina]

Streptococcus agalactiae is an endogenous bacterium that has emerged in the last 20 years as an etiological agent in both neonatal and perinatal infections, and in immunocompromised patients. The differentiation of the capsular polysaccharide, the presence of surface proteins c, X, R, and molecular methods allow classification in serotypes and genotypes. This identification is a useful tool for epidemiological purposes and virulence studies in this bacterium. The objective of this work was to study the serotypes and the antimicrobial susceptibility of isolates recovered from invasive diseases in different areas of Argentina. In the analyzed sample a fair predominance of Ia and III serotypes was recovered, followed by II and IV serotypes. All the isolates were found to be sensitive to penicillin. A 6% of resistance to erythromycin and a 4.5% to clindamycin were detected. In three of the isolates, constitutive MLS phenotype (resistance to macrolides, lincosamins and streptogramins) was founded, while in the remaining one, inducible MLS phenotype was detected. These results stress the importance of conducting a surveillance of the prevalent serotypes in our country with the goal of future prevention of this disease with an effective vaccine. The knowledge of the antimicrobial susceptibility profile will be also important to obtain therapeutic success in the treatment.

Oral administration of D-003, a mixture of very long chain fatty acids prevents casein-induced endogenous hypercholesterolemia in rabbits

D-003 is a mixture of very long chain saturated fatty acids (VLCSFA) purified from sugar cane wax with cholesterol-lowering effects proven in animal models and healthy volunteers. D-003 inhibits cholesterol biosynthesis through the regulation of HMG-CoA reductase activity. Rabbits fed diets enriched with casein develop endogenous hypercholesterolemia (EH), making them a very useful model for determining the mechanism of action of drugs affecting lipids. We examined whether D-003 prevented EH. Rabbits were fed a casein diet for 4 weeks, administered simultaneously with D-003 (5, 50, and 100 mg·kg–1·day–1). As expected, nontreated rabbits became hipercholesterolemic; however, as early as 15 days following administration, the treated group (50 and 100 mg·kg–1·day–1) had significantly decreased total cholesterol and low-density lipoprotein cholesterol (LDL-C). Triglycerides were not affected; however, at study completion, HDL-C levels significantly increased at all the doses assayed. D-003 inhibited de novo synthesis of cholesterol, since the incorporation of3H2O into sterols in the liver and proximal small bowel was significantly depressed. Also, D-003 significantly raised the rate of removal of [125I]-LDL from serum and significantly elevated [125I]-LDL binding activity to liver homogenates. Taken together, these results show that the efficacy of D-003 in reducing casein-derived hypercholesteromeia could involve, at least partially, an inhibition of hepatic cholesterol bio synthesis, which may elicit a decreased cholesterol concentration in hepatocytes, preventing the loss of hepatic LDL receptors induced by casein administration. However, since casein-induced hypercholesterolemia is also a consequence of a stimulation of cholesterol absorption in the lumen and an increase of the output of cholesterol associated with LDL, the effect of D-003 on cholesterol absorption and LDL synthesis by the liver should be investigated.Key words: D-003, very long chain saturated fatty acids, casein-fed rabbits, LDL-C, cholesterol biosynthesis, LDL clearance, LDL receptor.

The MELISSA pilot plant facility as as integration test-bed for advanced life support systems

The different advances in the Micro Ecological Life Support System Alternative project (MELISSA), fostered and coordinated by the European Space Agency, as well as in other associated technologies, are integrated and demonstrated in the MELISSA Pilot Plant laboratory. During the first period of operation, the definition of the different compartments at an individual basis has been achieved, and the complete facility is being re-designed to face a new period of integration of all these compartments. The final objective is to demonstrate the potentiality of biological systems such as MELISSA as life support systems. The facility will also serve as a test bed to study the robustness and stability of the continuous operation of a complex biological system. This includes testing of the associated instrumentation and control for a safe operation, characterization of the chemical and microbial safety of the system, as well as tracking the genetic stability of the microbial strains used. The new period is envisaged as a contribution to the further development of more complete biological life support systems for long-term manned missions, that should be better defined from the knowledge to be gained from this integration phase. This contribution summarizes the current status of the Pilot Plant and the planned steps for the new period.

Cross-reactivity of human and bovine antibodies in striped dolphin paraffin wax-embedded tissues

This study evaluates the cross-reactivity of seven anti-human and one anti-bovine antibodies in formalin-fixed, paraffin-embedded tissue samples of liver and mesenteric lymph nodes of 13 striped dolphins (Stenella coeruleoalba). Four antibodies (CD3, IgG, lysozyme and S100 protein) reacted with striped dolphin lymph nodes in a similar pattern to that observed in the species of origin. The anti-human MHC class II mAb reacted strongly with macrophages and dendritic-like cells of striped dolphins, whereas a small number of lymphocytes were labelled with this antibody. These antibodies were used to study the immunophenotype of the inflammatory infiltrated in non-specific chronic reactive hepatitis (eight cases) and chronic parasite cholangitis (two cases) and normal liver (three cases) of striped dolphins. Non-specific chronic reactive hepatitis was composed of inflammatory infiltration of CD3+ T lymphocytes and IgG+ plasma cells in portal spaces and hepatic sinusoids. Lymphonodular aggregates observed in chronic parasitic cholangitis showed a cellular distribution similar to that found in lymph node cortex, including the presence of S100+ and MHC class II+ dendritic-like cells in lymphoid follicles and interfollicular areas. This result suggests that those inflammatory infiltrates are highly organised to enhance antigen presentation to B and T cells.

[Clinical complications in a series of patients with anticardiolipin antibodies]

An analysis was made of clinical complications, determined with objective methods, in 68 patients at the University Clinic of Navarra with the clinical suspicion of antiphospholipid syndrome (APS) and presence of anticardiolipin antibodies (ACA). Patients with IgG higher than 23 GPL were considered for the study. The most prevalent pathology was thrombosis: venous thrombosis (42.6%) and arterial thrombosis (22%). Other complications were abortions (23.8% of the 42 women) and thrombocytopenia (12.1%). With respect to the localisation of venous thrombosis, predominance corresponded to lower extremities (51.7%), followed by superficial thrombophlebitis (27.5%) and pulmonary thromboembolism (20.6%). Among the arterial complications, the most frequent were cerebrovascular disease (86.6 %) and coronary disease (13.4%). There was no correlation between the presence of high values of ACA and the prevalence or severity of clinical manifestations. In the series of patients with ACA IgG>23 GPL, we appreciated a high percentage of venous and arterial thrombosis detected with objective methods. The presence of ACA constitutes a prothrombotic risk factor

Immunophenotypic characterization of hepatic inflammatory cell infiltrates in common dolphins (Delphinus delphis)

Of 14 common dolphins, 12 showed non-specific reactive hepatitis and three chronic parasitic cholangitis with lymphoid proliferation. Non-specific reactive hepatitis was shown immunohistochemically to be associated with small clusters of CD3(+) cells in portal areas and hepatic sinusoids. Polyclonal antibody against S100 protein reacted with a variable number of lymphocytes from portal areas and hepatic sinusoids, as well as with Kupffer cells and epithelial cells of the bile ducts. The majority of plasma cells observed in portal areas and hepatic sinusoids were IgG(+). In lymphonodular lesions of chronic parasitic cholangitis, the distribution of immunoreactive cells was similar to that found in the cortex of lymph nodes. The presence of stellate cells similar to follicular dendritic and interdigitating cells expressing S-100 protein and MHC class II antigen in lymphonodular lesions suggested that these were highly organized structures developed to enhance antigen presentation to B and T cells.

Cutaneous lesions in experimental acute and subacute African swine fever: an immunohistopathological and ultrastructural study

Histopathological, immunohistochemical and ultrastructural cutaneous changes are described in acute and subacute forms of experimental African Swine Fever (ASF). Fourteen 3-month-old Large White cross pigs were infected intramuscularly with the Dominican Republic 78 (DR78) ASF virus isolate and euthanized in pairs on alternatives days (3 to 17) post-inoculation (dpi). Three pigs were found dead at 8, 10 and 13 dpi, respectively. Antibodies against viral antigen Vp73, human fibrinogen, glycoprotein IIIa and Factor VIII-ra were used to evaluate viral antigen distribution, fibrin microthrombi and platelets in dermal vessels, respectively. Cutaneous lesions were characterised by vascular changes ranging from hyperaemia, mild oedema, scarce fibrin microthrombi and microhaemorrhages in euthanized animals, to generalized fibrin microthrombosis and microhaemorrhages in dead pigs. Secondary pustules and superficial folliculitis were observed in two animals dead at 10 and 13 dpi. Diffuse cytoplasmic Vp73 labelling was found in numerous intravascular monocytes and dermal macrophages. Ultrastructural studies showed mature viral particles in the lumen of dermal vessels but viral replication was not observed; nonetheless, microtubuloreticular structures were observed in the cytoplasm of some endothelial cells and macrophages which showed cytopathic effects, signs of cell activation or degeneration. Morphological and immunohistochemical evidences of platelet activation, degranulation and consumption were observed from 5 dpi onward.

[Analysis of survival in dialysis: hemodialysis versus peritoneal dialysis and the significance of comorbidity]

To choose the best possible dialysis technique for those patients with end-stage renal disease continues to be a matter of debate. Even after putting aside the evident influence that economic and geographic factors as well as the health politics may have in the selection of the technique, different studies comparing survival between hemodialysis (HD) and peritoneal dialysis (PD) have shown contradictory results which could be explained by the differing methodological and statistical methods used together with the different influence assigned to the comorbidity found when starting the treatment, a situation that has increased the confusion about this topic. Based on this we performed a retrospective analysis with a follow-up time of seven years including all those patients who started dialytic treatment in our area, with a final number of 3.106 hemodialysis patients and 542 peritoneal dialysis patients. Those patients who were transferred to another treatment technique during the time of the study were excluded. Age higher than 70 years, cardiovascular disease, liver disease, diabetes mellitus and the presence of dyslipidemia were included as comorbidity factors. Peritoneal dialysis patients were younger than those treated by hemodialysis (54.53 vs 60.1 years), but suffered from higher cardiovascular comorbidity and were more often diabetic. The global survival was the same in both groups up to 32 months of treatment. Although no differences were found when comparing those patients without comorbidity factors, those with comorbidity had better survival on hemodialysis. Age higher than 70 years was the only comorbidity factor with statistically significant difference for a better survival in hemodialysis.

Lung resistance-related protein as a predictor of clinical outcome in advanced testicular germ-cell tumours

This study was undertaken to investigate the expression and predictive value for outcome of multidrug resistance-associated (MDR) proteins P-glycoprotein (Pgp), MRP1, BCRP, and LRP, in advanced testicular germ-cell tumours (TGCT). Paraffin-embedded sections from 56 previously untreated patients with metastatic TGCT were immunostained for Pgp, MRP1, BCRP, and LRP. All patients received platinum-based chemotherapy after orchidectomy. Immunostaining was related to clinicopathological parameters, response to chemotherapy, and outcome. Strong and intermediate expressions of the different MDR-related proteins were: 27 and 41% (Pgp), 54 and 37% (MRP1), 86 and 7% (BCRP), and 14 and 29% (LRP). P-glycoprotein and MRP1 associated, respectively, to low AFP (P=0.026) and high LDH levels (P=0.014), whereas LRP expression associated with high beta-hCG levels (P=0.003) and stage IV tumours (P=0.029). No correlation was found between Pgp, MRP1, and BCRP expression and response to chemotherapy and survival. In contrast, patients with LRP-positive tumours (strong or intermediate expression) had shorter progression-free (P=0.0006) and overall survival (P=0.0116) than LRP-negative patients, even after individual log-rank adjustments by statistically associated variables. Our data suggest that a positive LRP immunostaining at the time of diagnosis in metastatic TGCT is associated with an adverse clinical outcome.

Effects of D-002 on Lipid Peroxidation in Older Subjects

D-002 is a mixture of higher aliphatic alcohols isolated from beeswax that inhibits rat microsomal lipid peroxidation in vitro and in vivo. This study was undertaken to investigate whether D-002 also inhibits lipid peroxidation in older subjects. The free radical theory of aging suggests that progressive defects in the protection against free radical reactions leads to progressive deleterious effects of free radicals on cells and tissues. This free radical damage has been implicated in several pathophysiological processes associated with the chronic degenerative diseases that occur with aging. Forty-eight older subjects were randomly assigned, in a double-blind fashion, to receive placebo or D-002 tablets (50 mg/day) once daily. At baseline, D-002 and placebo groups were well matched regarding several variables. D-002 significantly reduced the susceptibility of nonfractionated plasma samples to copper-mediated lipid peroxidation. It also significantly increased the length of the lag phase (P <.001) and the total antiioxidant status (P <.05) compared with baseline and placebo. In addition, D-002 significantly decreased malondialdehyde levels (expressed in terms of thiobarbituric acid reactive substances (TBARS, P <.001) compared with baseline, but not with placebo. No significant changes on lipid peroxidation parameters were observed in the placebo group. We conclude that D-002 treatment may be useful to prevent or manage certain pathophysiological conditions in the elderly.

[Parotid tuberculosis following intravesical BCG instillation: a case report]

First case of parotid gland tuberculosis publicated to date is presented after intravesical instillation of BCG for a superficial bladder cancer. The diagnosis of the parotid gland tuberculosis is difficult because it is usually indistinguishable from a neoplasm. Combined fine-needle aspiration cytology with PCR or LCR amplification of mycobacterial DNA could be a good diagnostic tool avoiding an open biopsy.

MELISSA: a loop of interconnected bioreactors to develop life support in space

The development of a loop of interconnected continuous bioreactors, aimed to provide life support in space, is reported. The complete loop concept consists of four bioreactors and one higher plant compartment. For its realization the continuous and controlled operation of the bioreactors is characterized, up to the pilot scale level, first for each individual reactor, second for the interconnected reactor operation. The results obtained with the two more advanced bioreactors in the Micro Ecological Life Support System Alternative (MELISSA) loop are described more specifically. These reactors consist of a packed-bed reactor working with an immobilized co-culture of Nitrosomonas and Nitrobacter cells, and an external loop gas-lift photobioreactor for the culture of the cyanobacteria Spirulina platensis. Their individual operation for long duration runs has been achieved and characterized, and their interconnected operation at pilot scale is reported.

Determination of triazines in water samples by high-performance liquid chromatography with diode-array detection

Triazines are widely used herbicides that can be detected in the environment at trace level. A preconcentration step is necessary to determinate them before analysis. In this study, carbonaceous and polymeric adsorbents are compared with C18 for the solid-phase extraction of simazine, atrazine, and propazine in water samples in order to quantitate their levels by high-performance liquid chromatography using photodiode-array detection.

[Kleine-Levin syndrome: contribution of brain SPECT in diagnosis]

INTRODUCTION

Kleine Levin syndrome is an infrequent disorder of uncertain aetiopathogenesis that usually affects adolescent males, producing drowsiness and alterations in behaviour, appetite and sexuality. We report a clinically typical case in which the brain SPECT showed right frontal hypoperfusion.

CASE REPORT

Male aged 17, right handed, who presented drowsiness, apathy, alterations in his sexual behaviour (masturbations in public and attempted assault of women) and hyperphagia, which coincided with his undergoing an emotionally stressful period in his life. Brain SPECT revealed reduced flow in the right frontal lobe, although MRI and CSF study were normal. The polysomnographic study revealed a destructured pattern of sleep, with a reduction in phases III and IV and in REM sleep. He was treated with lithium and evolved favourably without any relapses during the 18 month follow up.

CONCLUSIONS

Cases of Kleine Levin syndrome with structural lesions have been reported, but most of them are idiopathic. A disorder in the hypothalamus and the limbic system is suggested. In our case, the findings from the brain SPECT confirmed a non dominant hypoperfusion of the frontal lobe, which could result from a phenomenon of diaschisis brought about by a diencephalic dysfunction.

Role of dopamine in renal dysfunction during laparoscopic surgery

BACKGROUND

Sympathetic vascular insult and hemodynamic changes represent the most reliable explanation of renal impairment resulting from acute intraabdominal pressure. We evaluated the effects of low-dose dopamine administration during a long-lasting surgical laparoscopic procedure.

METHODS

For this study 40, patients submitted to a colorectal laparoscopic procedure with 15 mmHg of intraabdominal pressure were randomly allocated to two groups: 20 receiving 2 mg/kg/min of dopamine and 20 receiving the same perfusion of saline. Hemodynamic parameters, renal function, urinary output, and creatinine clearance, were studied.

RESULTS

The hemodynamic parameters were similar in both groups. The urinary output decreased during the intraoperative period only the saline group (p = 0.4). Then 2 h postoperatively, it increased in both groups, and no statistically significant differences were found between the groups. The creatinine clearance decreased in both groups during the intraoperative time, but it was worse in the saline group (-28 +/- 120 vs -194 +/- 106; p = 0.022). During the postoperative period, both groups showed improvement, but in control group the values remained lower than at baseline (p = 0.04), and significantly lower than in the dopamine group (230 +/- 337 vs 100 +/- 192; p = 0.012).

CONCLUSIONS

An intrabdominal pressure of 15 mmHg induces a time-limited renal dysfunction, and low doses of dopamine could prevent this undesirable effect.