Unilateral left prosopometamorphopsia: A neuropsychological case study

We describe a patient who suddenly developed prosopometamorphopsia after a childbirth; she claimed that the left half of well-known and unfamiliar faces looked distorted. Brain MR was normal, whereas SPECT showed hypoperfusion of the left infero-lateral occipital cortex. No visual recognition defects for objects or faces were present. In three matching tasks with half-faces (Experiment 1), chimeric faces (Experiment 2), or chimeric objects (Experiment 3), the patient was impaired only when she matched pairs of chimeric faces differing in their left half; the same results were obtained after 1 year. This is the first behavioural demonstration of selective chronic metamorphopsia for the left side of faces, and provides new insights for models of face processing.     

Effect of ascorbic acid based amphiphiles on human erythrocytes membrane

6-O-alkyl ascorbic acid esters (ASCn) are amphiphilic molecules that behave as surfactants in aqueous solution. These compounds show physico-chemical and aggregation properties that depend on the alkyl chain length, pH and temperature. It must consider that ASCn have shown some physical and rheological properties that suggest a potential utility as drug carriers. The present paper aims to evaluate the effects of these surfactants on human erythrocyte membranes. The membrane properties studied were: osmotic resistance in hypotonic media, shape transformation, and vesicle release at lytic concentration. According to our results, all properties depended on the length of the hydrophobic chain and they did not evolve monotonically. Finally, the study of ASCn interaction with erythrocyte membrane allowed us to postulate the crucial influence that the molecular structure exerts upon the manner in which amphiphiles interact with biological membranes and the effects involved in them.     

Effect of administration of pre-warmed intravenous fluids on the frequency of hypothermia following spinal anesthesia for Cesarean delivery

Study ObjectiveTo determine whether administration of pre-warmed colloid followed by pre-warmed crystalloid solution prevents the development of hypothermia in patients undergoing Cesarean delivery.DesignRandomized, double-blind, placebo-controlled study.Patients30 parturients scheduled to undergo elective Cesarean delivery during spinal anesthesia.InterventionsPatients assigned to the warmed fluid group (n=15) received pre-warmed colloid with average molecular weight of 70,000 daltons and substitution ratio of 0.55, followed by pre-warmed crystalloid (kept in warmed storage maintained at 41 °C) during surgery. Patients assigned to the unwarmed fluid group (n=15) received non-warmed infusion. All patients received 400 mL before spinal anesthesia followed by another 300 mL before delivery of the newborn. After completion of a 1,000 mL infusion of colloid fluid, acetate Ringer's solution was infused.MeasurementsCore temperature measured at the tympanic membrane, and forearm and fingertip skin temperatures were recorded just after arrival at the operating room (baseline), after administration of spinal anesthesia (spinal ), at incision (incision), at delivery of the newborn (delivery), and at 15, 30, and 45 minutes after delivery. Rectal temperature of the baby, Apgar scores at one and 5 minutes after delivery, and umbilical artery pH were evaluated.Main ResultsCore temperature was significantly higher in the warmed fluid group from the time of delivery to 45 minutes after delivery. Apgar scores at one minute after delivery and umbilical arterial pH were significantly higher in the warmed fluid group.ConclusionAdministration of pre-warmed intravenous colloid followed by crystalloids maintained core temperature during Cesarean delivery and induced higher Apgar scores and umbilical arterial pH.     

Secondary and ectopic lymphoid tissue responses in rheumatoid arthritis: from inflammation to autoimmunity and tissue damage/remodeling

Summary: Rheumatoid arthritis is a chronic systemic inflammatory disease primarily affecting the synovium of diarthrodial joints. Despite the currently unknown etiology, overwhelming evidence indicates that both innate and adaptive immunity play a central role in disease pathogenesis. In this review, we consider recent evidence examining the mechanisms of lymphoid tissue reactivity in rheumatoid arthritis with a focus on the dynamics controlling secondary and ectopic lymphoid tissue response. We then examine the cellular and molecular mechanisms regulating the biopathology of these processes with specific emphasis on cell trafficking, contribution to autoimmunity, and joint damage-repair. We finally provide a brief overview of the most recent studies addressing the clinical relevance of synovial lymphoid tissue analysis as a diagnostic and prognostic tool as well as its response to current biological therapies.     

Drug release from carbomer:carbomer sodium salt matrices with potential use as mucoadhesive drug delivery system

In vitro mucoadhesion, water uptake, and drug release of nystatin (N) from matrices of carbomer (C) and lyophilized carbomer sodium salt (CNaL) mixtures were evaluated. Matrices with different ratios C:CNaL were prepared by direct compression. Commercial C as well as lyophilized powder (CL) were used. In vitro mucoadhesion increased as the proportion of C in the matrix was raised. The same effect was observed when C was replaced by CL. Matrices in which C was replaced by CL showed an increase of both water uptake and release rates. Besides, the release of N from matrices CL:CNaL exhibited a kinetics with Super Case II (n>1) mechanism. However, for C:CNaL matrices, drug release was slower and exhibited a biphasic profile with a first stage characterized by either an anomalous (n<1, for C>or=50%) or a Case II (n approximately 1.0, C<50%) mechanisms. After that period, the mechanism changed to Super Case II transport (n>1).     

Development of a chromatographic bioreactor based on immobilized beta-glucuronidase on monolithic support for the determination of dextromethorphan and dextrorphan in human urine

We here reported the development and application of an immobilized enzyme reactor (IMER) based on β-glucuronidase to the on-line determination of urinary molar ratios of dextromethorphan (DOMe)/dextrorphan (DOH) for the assessment of the metabolic activity of CYP2D6, a genetically variable isoform of cytochrome P-450 (CYP).

β-Glucuronidase was immobilized on an HPLC monolithic aminopropyl silica support. Catalytic activity and stability of the chromatographic reactor were evaluated using 8-hydroxyquinoline glucuronide (8-HQG) as substrate. The IMER was coupled through a switching valve to a reversed-phase column (C8) for the simultaneous determination of dextromethorphan and its main metabolite dextrorphan. On purpose a selective reversed-phase ion pair HPLC method coupled with fluorescence detection was developed. Urine samples were first centrifuged to remove insoluble materials and then aliquots of the supernatants were injected into the coupled-column analyser.

Linearity, precision and accuracy of the method were established. The method reliability was verified by comparing our data with previous data of a phenotyping study carried out by the Poison Control Centre of Pavia-Clinical Toxicology Division.     

Role of chemokines and chemokine receptors in regulating specific leukocyte trafficking in the immune/inflammatory response

Antigen recognition, lymphocyte priming and effector responses in inflamed tissues depend on a coordinated and sequential series of events that take place in different anatomical compartments. The integration of these processes is favoured by the dynamic capacity of leukocytes to recirculate between the bloodstream and specific organs and to navigate inside the tissues in a programmed fashion, regulated by a complex interaction of cell adhesion molecules and soluble chemoattractants, in particular chemokines. In this review we discuss the role of chemokines and chemokine receptors in regulating leukocyte trafficking in different anatomical sites in the context of distinct functional phases of the immune/inflammatory response.     

Equilibrium properties and mechanism of kinetic release of metoclopramide from carbomer hydrogels

Equilibrium properties and kinetics of metoclopramide release of carbomer-metoclopramide (C-M) hydrogels are reported. A set of (C-M)(X) (x=moles percent of M=50, 75, 100) that covers a pH range between 6.49 and 8.40 was used. Hydrogels exhibited a high negative electrokinetic potential (zeta). Concentrations of ion pair [R-COO(-)MH(+)] and free species [M] and [MH(+)] were determined by the selective extraction of M with 1,2-dichloroethane (DCE) together with pH measurements. The system (C-M) is characterized by a high proportion of drug present in the form of ion pairs and a negative zeta potential that attracts MH(+) and H(+) and repeals OH(-), providing a microenvironment of higher acidity than the bulk medium. Delivery rates of M were measured in a Franz type bi-compartmental device using water and NaCl 0.9% solution as receptor media. (C-M) hydrogels behave as a reservoir that releases the drug at a slow rate to water; the rate increases 14 times as water is replaced by NaCl solution. The pH effect on delivery rate suggests that, under the main conditions assayed, the rate of dissociation of R-COO(-)MH(+) together with the low change of pH in the polyelectrolyte environment are the factors that control releasing rates.     

Platelet monoamine oxidase B activity as a state marker for alcoholism: trend over time during withdrawal and influence of smoking and gender

- AIMS AND METHODS: The present study evaluated time-related changes in platelet monoamine oxidase B (MAO-B) activity in an Italian cohort of alcohol-dependent subjects (n = 98) during early abstinence, and the effect of potential confounding factors, such as gender and smoking status, on the temporal trend of the enzyme activity. RESULTS: While still under the influence of ethanol (time point T1), the mean value of platelet MAO-B activity in alcoholics was 6.4 +/- 3.1 nmol/mg of protein/h. This increased by >40% (to 9.3 +/- 4.4 nmol/mg of protein/h) after 8 days of withdrawal (T2), and remained stable thereafter (T3 and T4: 15 and 22 days of abstinence, respectively). In a cohort of 138 healthy subjects, MAO activity levels averaged 9.9 +/- 0.9 nmol/mg of protein/h. In the group of alcoholic patients, alcohol intake cessation was confirmed by the progressive decrease of serum % carbohydrate-deficient transferrin (CDT), which was pathologically above the reference limits (6%) at T1 (7.8 +/- 3.3%), declined to 6.6 +/- 2.1% at T2 and reached physiological values at T3 and T4. In a subgroup of cirrhotic alcoholics, %CDT did not decrease over time, while MAO activity rose after the first week of abstinence, without further change at T3 and T4. During early withdrawal, neither gender nor tobacco smoking affected the temporal pattern of MAO activity. CONCLUSIONS: MAO-B can be regarded as a state marker of alcohol consumption. The temporal pattern of platelet MAO-B activity may be used for the diagnostic assessment of alcoholism and early abstinence, regardless of gender and smoking status.