Increased levels of adenosine and ecto 5'-nucleotidase (CD73) activity precede renal alterations in experimental diabetic rats

The pathogenesis of diabetic nephropathy (DN) has not been clearly established, making diagnosis and patient management difficult. Recent studies using experimental diabetic models have implicated adenosine signaling with renal cells dysfunction. Therefore, the study of the biochemical mechanisms that regulate extracellular adenosine availability during DN is of emerging interest. Using streptozotocin-induced diabetic rats we demonstrated that urinary levels of adenosine were early increased. Further analyses showed an increased expression of the ecto 5'-nucleotidase (CD73), which hydrolyzes AMP to adenosine, at the renal proximal tubules and a higher enzymatic activity in tubule extracts. These changes precede the signs of diabetic kidney injury recognized by significant proteinuria, morphological alterations and the presence of the renal fibrosis markers alpha smooth muscle actin and fibronectin, collagen deposits and thickening of the glomerular basement membrane. In the proximal tubule cell line HK2 we identified TGF-β as a key modulator of CD73 activity. Importantly, the increased activity of CD73 could be screened in urinary sediments from diabetic rats. In conclusion, the increase of CD73 activity is a key component in the production of high levels of adenosine and emerges as a new tool for the early diagnosis of tubular injury in diabetic kidney disease.

Prenatal protein restriction alters synaptic mechanisms of callosal connections in the rat visual cortex

Mild prenatal protein malnutrition, induced by reduction of the casein content of the maternal diet from 25 to 8%, calorically compensated by the addition of excess carbohydrates, leads to so-called "hidden" malnutrition in the rat. This form of malnutrition results in normal body and brain weights of pups at birth, but in significant alterations of their central nervous system neurochemical profiles. Since severe forms of prenatal malnutrition induce morpho-functional deficits on callosal interhemispheric communication together with brain neurochemical disturbances, we evaluated, in rats born from mothers submitted to an 8% casein diet, the potassium-induced release of [3H]-noradrenaline in visual cortex slices, as well as functional properties of callosal-cortical synapses by determining cerebral cortical excitability to callosal inputs and fatigability and temporal summation of transcallosal evoked responses. Rats born from mothers submitted to a 25% casein diet served as controls. At birth prenatally malnourished pups had significantly higher cortical percent net noradrenaline release (14.79 +/- 1.11) than controls (9.14 +/- 1.26). At 45-50 days of age, rehabilitated previously malnourished rats showed, when compared to controls; (i) significantly reduced percent net noradrenaline release in the visual cortex (4.50 +/- 0.52 vs 11.31 +/- 1.14); (ii) decreased cortical excitability to callosal inputs as revealed by significantly increased chronaxie (607.2 +/- 82.8 microseconds vs 351.3 +/- 47.7 microseconds); (iii) enhanced fatigability of transcallosal evoked responses as revealed by significantly decreased stimulus frequency required to fatigate the responses (4.9 +/- 0.8 Hz vs 9.2 +/- 1.3 Hz); and (iv) decreased ability of callosal-cortical synapses to perform temporal summation, as revealed by significantly reduced percent response increment to double-shock (54.2 +/- 6.2 vs 83.0 +/- 11.0, for a 3.2-ms interstimulus time interval). These changes, resulting from mild prenatal protein restriction, are discussed in relationship to developmental processes leading to the formation of synaptic contacts between callosal axons and their appropriate cortical target during perinatal age.

The microtubular cytoskeleton of olfactory neurons derived from patients with schizophrenia or with bipolar disorder: Implications for biomarker characterization, neuronal physiology and pharmacological screening

Schizophrenia (SZ) and Bipolar Disorder (BD) are highly inheritable chronic mental disorders with a worldwide prevalence of around 1%. Despite that many efforts had been made to characterize biomarkers in order to allow for biological testing for their diagnoses, these disorders are currently detected and classified only by clinical appraisal based on the Diagnostic and Statistical Manual of Mental Disorders. Olfactory neuroepithelium-derived neuronal precursors have been recently proposed as a model for biomarker characterization. Because of their peripheral localization, they are amenable to collection and suitable for being cultured and propagated in vitro. Olfactory neuroepithelial cells can be obtained by a non-invasive brush-exfoliation technique from neuropsychiatric patients and healthy subjects. Neuronal precursors isolated from these samples undergo in vitro the cytoskeletal reorganization inherent to the neurodevelopment process which has been described as one important feature in the etiology of both diseases. In this paper, we will review the current knowledge on microtubular organization in olfactory neurons of patients with SZ and with BD that may constitute specific cytoskeletal endophenotypes and their relation with alterations in L-type voltage-activated Ca(2+) currents. Finally, the potential usefulness of neuronal precursors for pharmacological screening will be discussed.

Clinical outcomes and costs of cataract surgery performed by planned ECCE and phacoemulsification

PURPOSE

To compare clinical outcomes and costs of cataract surgery between patients operated with standard extracapsular extraction (ECCE) and those undergoing phacoemulsification.

SETTING

Patients from the Ophthalmology Department of a teaching hospital in Barcelona (Spain) scheduled for cataract surgery, not combined with any other ophthalmic procedure.

METHODS

A retrospective analysis has been performed on a database of 1046 patients undergoing ECCE and phacoemulsification. The outcome measures used were: surgical complications, visual acuity and costs of surgery and of follow-up. Overall rate of all complications and postoperative visual acuity were compared between the two groups, adjusting for age, preoperative visual acuity, medical and ocular comorbidity.

RESULTS

31.9% of the patients (334) underwent phacoemulsification, and 68.1% (712) underwent ECCE. Patients undergoing phacoemulsification presented a frequency of intra- and postoperative complications lower than those undergoing ECCE (odds ratio 0.57, 95%CI 0.37-0.87 and 0.66, 95%CI 0.46-0.96, respectively), specifically for intraoperative iris trauma (3.1% vs 0.3%, p = 0.004), residual posterior capsular opacity (2% vs 0.3%, p = 0.035) and postoperative corneal edema (7.4% vs 3.6%, p = 0.016). Costs of intervention and follow-up were lower for phacoemulsification compared with ECCE (23.9% and 14%, respectively). But global costs were slightly higher for phacoemulsification (4.87%), due to supply costs, which were more than twice those of ECCE.

CONCLUSIONS

Phacoemulsification, when performed by an experienced surgeon, has better clinical outcomes than planned extracapsular extraction, and costs may be lower since supply costs are expected to decrease as the phacoemulsification technique becomes more widespread.

Clonidine treatment during gestation prevents functional deficits induced by prenatal malnutrition in the rat visual cortex

It has been shown that prenatal malnutrition results at birth in increased concentration of noradrenaline (NA) in the brain. Besides, it is known that NA is an important regulator of normal regressive processes occurring during synaptogenesis such as cell death, axonal pruning and synaptic elimination. The present study was designed to investigate (i) whether prenatal malnutrition enhances the NA release in the visual cortex and (ii) whether or not chronic administration of clonidine during gestation may prevent long-term deleterious effects of fetal malnutrition on functional properties of interhemispheric connections of the visual cortex and on the interhemispheric asymmetry of visual evoked responses. Prenatal malnutrition was induced by restricting food consumption to pregnant rats from Day 8 postconception to parturition. Results show that at birth, prenatally malnourished rats had higher NA release than normals. At 45-50 days of age, the malnourished group exhibited (a) reduced peak-to-peak amplitude and diminished extent of the projecting field of transcallosal evoked responses, and (b) abolished interhemispheric asymmetry of visual evoked responses. Clonidine administration to malnourished mothers from Day 14 postconception to parturition (10 g/kg/day s.c.), prevented in the offspring disorders induced by prenatal malnutrition on cortical NA release, on interhemispheric connectivity of visual areas and on interhemispheric bioelectrical asymmetry, probably by restoring the normal trophic role of NA during synaptogenesis. Results are discussed in relationship to normal regressive events occurring during early brain development.

Effects of morphine: an electrophysiological study on guinea-pig papillary muscle

Intracellular microelectrodes were used to study the electrophysiological effects of morphine on guinea-pig papillary muscle. Morphine (5 × 10−4  m) caused a significant decrease in the maximum rate of depolarization. At high concentrations (5 × 10−3  m) morphine induced a decrease in the action potential amplitude and a prolongation of the action potential duration. The administration of naloxone (10−7  m) partially antagonized the cardiac electrophysiological effects of morphine. These results suggest that the electrophysiological effects of morphine may be due to an interaction with opioid receptors.

[Papilledema as an indicator of POEMS syndrome]

CASE REPORT

We present the case of a 54-year-old woman with papilledema associated to POEMS syndrome. The presence of intracranial hypertension was detected and treatment started with acetazolamide.

DISCUSSION

The most common ophthalmological pathology in POEMS syndrome is papilledema, the etiology of which could be infiltrative, intracranial hypertension, inflammation or an increase of the vascular permeability. The correct diagnosis and treatment of papilledema, depending on its etiology, should permit an acceptable visual outcome to be achieved.

Endocrine, metabolic and apical effects of in utero and lactational exposure to non-dioxin-like 2,2',3,4,4',5,5'-heptachlorobiphenyl (PCB 180): A postnatal follow-up study in rats

PCB 180 is a persistent and abundant non-dioxin-like PCB (NDL-PCB). We determined the developmental toxicity profile of ultrapure PCB 180 in developing offspring following in utero and lactational exposure with the focus on endocrine, metabolic and retinoid system alterations. Pregnant rats were given total doses of 0, 10, 30, 100, 300 or 1000 mg PCB 180/kg bw on gestational days 7-10 by oral gavage, and the offspring were sampled on postnatal days (PND) 7, 35 and 84. Decreased serum testosterone and triiodothyronine concentrations on PND 84, altered liver retinoid levels, increased liver weights and induced 7-pentoxyresorufin O-dealkylase (PROD) activity were the sensitive effects used for margin of exposure (MoE) calculations. Liver weights were increased together with induction of the metabolizing enzymes cytochrome P450 (CYP) 2B1, CYP3A1, and CYP1A1. Less sensitive effects included decreased serum estradiol and increased luteinizing hormone levels in females, decreased prostate and seminal vesicle weight and increased pituitary weight in males, increased cortical bone area and thickness of tibial diaphysis in females and decreased cortical bone mineral density in males. Developmental toxicity profiles were partly different in male and female offspring, males being more sensitive to increased liver weight, PROD induction and decreased thyroxine concentrations. MoE assessment indicated that the 95^th percentile of current maternal PCB 180 concentrations do not exceed the estimated tolerable human lipid-based PCB 180 concentration. Although PCB 180 is much less potent than dioxin-like compounds, it shares several toxicological targets suggesting a potential for interactions.

Diazoxide blocks the morphine induced lengthening of action potential duration on guinea-pig papillary muscle

1. Intracellular microelectrodes were used to evaluate the possible involvement of potassium currents in the action potential prolongation induced by morphine. To this purpose we investigated the electrophysiological effect of morphine on the isolated guinea pig right ventricular papillary muscle in the presence of the potassium channel opener and inhibitor diazoxide and glibenclamide respectively. 2. Diazoxide (1 microM), which is devoid of effect on its own, blocks the lengthening of action potential duration (APD) induced by morphine (5 mM). 3. However, in the presence of glibenclamide (1 microM), morphine (5 mM) prolonged APD in approximately the same proportion as that observed when used alone. 4. These results suggest that diazoxide but not glibenclamide sensitive potassium channels could mediate the APD prolongation induced by morphine.

Enhancement of central noradrenaline release during development alters the packing density of neurons in the rat occipital cortex

The effect of chronic yohimbine treatment early in life on packing density of neurons was evaluated in the occipital cortex of young rats. Yohimbine administration to pups between days 5 and 16 of postnatal life (2.5 mg/kg/day i.p.) resulted at 45 days of age in significantly higher neuronal density in layers II-V of the occipital cortex, the effect being more marked in the dorsal region than in the dorsolateral and lateral ones. Results suggest a relationship between enhanced central noradrenaline activity and altered development of the neuropil in the occipital cortex.

Electrophysiological effects of opioid receptor selective agonists on guinea-pig papillary muscle

The cardiac electrophysiological effects of DAMGO, DPDPE and U-50,488H which are selective opioid agonists for mu, delta and kappa receptors, respectively, were studied in the isolated guinea-pig right ventricular papillary muscles. Neither DAMGO (5.10(-6)-5.10(-5)M) nor DPDPE (5.10(-6)-5.10(-5)M) produced any significant effect on the action potential characteristics. However, U.-50,488H (10(-5),5.10(-5) M) caused a concentration-dependent reduction in the maximum rate of depolarization of phase 0 (Vmax) and in the action potential duration measured at 50% repolarization, APD50 and 90% repolarization, APD90. At 5.10(-5) M it also produced a decrease of action potential amplitude (APA). These results suggest that the reported electrophysiological effects of U-50,488H on the cardiac muscle action potential, may be, at least in part, explained by a direct cardiac action.

Cardiac electrophysiological effects of U-50,488H on guinea-pig papillary muscle

Intracellular microelectrodes were used to study the electrophysiological effects of U-50,488H on guinea-pig papillary muscle. U-50,488H (10(-5) M) caused a significant decrease in the maximum rate of depolarization and a decrease in the action potential duration. At high concentration (5 x 10(-5) M) U-50,488H induced a significant decrease of resting potential, maximum rate of depolarization, action potential amplitude and the action potential duration. The administration of MR-2266 (5 x 10(-7) M) partially antagonized the cardiac electrophysiological effects of U-50,488H. These results suggest that the electrophysiological effects of U-50,488H may be partially due to an interaction with opioid receptors.

[Self-adjusting monocanalicular intubation for congenital lacrimal obstruction]

OBJECTIVE

To present our work with the Masterka self-adjusting monocanalicular intubation without nasal recuperation in congenital lacrimal obstruction in children over 12-months old.

METHODS

A total of 40 children between the ages of one and seven (average age 2.6 years) were consecutively operated on. The Masterka catheter has a flexible metal guide inside the silicone tube that covers it completely. The proximal end is fixed onto the lacrimal punctum by pushing it with a dilator or forceps. Its correct position was monitored and visually checked in real time during surgery in all cases.

RESULTS

The average surgery time, excluding anaesthetic, was 1.56min, ranging from 1.05 to 4min. The final success was 97.5%, considering absence of epiphora, disappearance of colouring in lacrimal meniscus, and mucopurulent secretion. The average follow-up time was 15 months (ranging from 7 to 21 months).

CONCLUSIONS

Masterka intubation is an effective primary treatment. It is no more difficult than a simple catheter, since the surgical technique is similar, but with better functional results. It avoids the possibility of having to repeat the catheterization and it is easier to carry out than bicanalicular intubation, since there is no need to manipulate repeatedly or use surgical instruments in the inferior meatus, thus simplifying the process.

[Psychomotor development from 0 to 4 years in indigenous children. A sistematic literature search]

INTRODUCTION

The objective of this study was to evaluate published articles regarding the development of indigenous children aged 0 to four years.

SUBJECTS AND METHOD

Systematic literature search. Parti cipants: Primary studies with populations of indigenous children aged 0 to four years. Type of studies: Primary studies with qualitative or quantitative methodologies published in the last ten years until November 2015. Databases: MEDLINE, Digital Library of the University of Girona: CERCADOR, EMBASE, Scielo.

SEARCH STRATEGY

sensitive and specific. Free terms, MeSH, and Boolean.

RESULTS

Nine articles remain for analysis. There are six central subjects related to intracultural patterns of expected development in indigenous childhood: 1) physical, 2) language, 3) socio-cognitive, 4) emo tional, 5) teaching-learning, 6) psychosocial, which reveal the existence of categories of sociocultural and spiritual contents. There is no defined period of time associated with the education. Learning is through observation and participation. Development is understood as a whole, intertwining the social, cultural, natural and spiritual.

CONCLUSION

Spirituality and nature are at the center. Time as a goal to gain skills does not have a cultural function to demonstrate the acquisition of the inherent va lues to the culture. To base the assessment of development exclusively on psychomotor development as monitoring guide is insufficient to assess the integrality and complexity of the advances, abilities, and skills of indigenous children.