Pooling Saliva Sample as an Effective Strategy for the Systematic CMV Screening of Newborns-A Multicentric Prospective Study

BACKGROUND

Cytomegalovirus is the most common cause of congenital infections worldwide. Screening all newborns in the first 2 weeks of life is the only way to detect all cases of congenital infection, allowing the monitoring of children with asymptomatic infection at birth and early intervention.

AIM

In this multicenter study, we aimed to evaluate the feasibility of using a saliva pool strategy for mass screening in 7 Portuguese hospitals, and to estimate the current prevalence of this congenital infection in these hospitals.

METHODS

A total of 7033 newborns were screened between June 2020 and June 2022, and 704 pools of 10 saliva samples were analyzed by polymerase chain reaction (PCR).

RESULTS

Of the 704 pools analyzed, 685 were negative and 19 had positive PCR results for cytomegalovirus. After individual PCR testing, 26 newborns had positive saliva results, of which 15 were confirmed by urine testing. Thus, this study's prevalence of congenital infection was 0.21% (95% confidence interval: 0.12%-0.35%).

CONCLUSIONS

In this study, the pooling strategy proved to be effective for the systematic screening of newborns, although this low prevalence raises questions regarding the cost-effectiveness of implementing universal screening. However, this prevalence is probably the result of the control measures taken during the pandemic; therefore, the rates are expected to return to prepandemic values, but only a new study after the pandemic will be able to confirm this.

Designing a Nurse-Led Program for Self-Management of Substance Addiction Consequences: A Modified e-Delphi Study

Therapeutic interventions for people with problematic use of psychoactive substances can help tackle specific needs related to substance addiction consequences. This modified e-Delphi study aimed to establish consensus on a training program for self-management of substance addiction consequences. The study was conducted between February and April 2022, with an experts' sample of 28 participants in the first round and 24 in the second. A priori consensus criteria were defined for each round. The results revealed a very strong consensus was achieved on the structure of the program and on clinical areas, such as the problematic use of substances, general health knowledge, health-seeking behavior and adherence, self-knowledge and well-being, social role and personal dignity, and family process. Additionally, over 80% participant consensus was achieved on an extensive number of interventions categorized as psychoeducational, psychotherapeutic, socio therapeutic, brief interventions, social skills training, problem solving techniques, relaxation techniques, and counseling. These findings may be able to fulfill a gap concerning structured treatment approaches for people with problematic use of psychoactive substances. Supporting self-management of the consequences of substance addiction and its application can change nurses' interventions.

Structured programs for the self-management of substance addiction consequences in outpatient services: A scoping review

Structured intervention programs are an important resource for supporting people with substance addiction. Although evidence suggests that they improve health outcomes, such as specific symptoms, less is known about their impact on patients’ ability to self-manage the consequences of substance addiction. The aim of this review is to scope outpatient intervention programs focused on the self-management of substance addiction consequences. Approach. This review followed the Joanna Briggs Institute (JBI) methodology for scoping reviews. MEDLINE and CINAHL (through Ebsco), Psychology & Behavioral Sciences Collection (including PsycINFO) and Web of Science were screened to identify articles published in the last 10 years. Only primary research was included. Out of 891 records, 19 were eligible for this review—12 randomized controlled trials (RCT), 6 quasi-experimental study and 1 observational study. Those studies reported group interventions (10), individual interventions (8) and 1 mixed approach. The most common interventions were based on motivational strategies, relapse prevention and definition of active plans for risky situations. 10 studies reported positive effects. The identification of structured programs may support the development of new approaches focused on empowerment and quality of life of people with substance addiction. Programs to empower patients for self-management of substance addiction consequences are often complex and rely on health professionals’ commitment. Nevertheless, they are a feasible approach that seems to benefit patients managing chronic conditions associated with substance addiction.

Programa de suporte medicamentoso com pessoas dependentes de substâncias: Satisfação com os cuidados de enfermagem

Contexto: Na saúde, a satisfação com os cuidados recebidos é um indicador relevante para a qualidade e é fundamental para a adesão terapêutica dos utentes. Objetivos: Caraterizar a satisfação com os cuidados de enfermagem numa população atendida por enfermeiros num programa de suporte medicamentoso para pessoas dependentes de substâncias. Métodos: Estudo quantitativo, observacional de corte transversal. Amostra de conveniência acedida em janeiro 2019. Elaborou-se um questionário para caraterização sociodemográfica e psicossocial, e utilizada a “Escala da satisfação dos utentes com os cuidados de enfermagem no centro de saúde”, com 22 itens [resposta entre 0-66], que avaliam a satisfação em 6 dimensões (Qualidade na assistência; Envolvimento do utente; Formalização da informação; Promoção de elo de ligação; Informação de recursos; Individualização da informação). Obteve-se o parecer positivo de uma comissão de ética. Resultados: Participaram 181 (n) pessoas. Obteve-se um Alpha de Cronbach da escala, de 0,892. A média apurada foi 59,36 dp=8,19 [23-66]. A subescala que revelou maior índice de satisfação foi “Individualização da informação” (itens relacionados com explicação da informação, de forma compreensível, por parte dos enfermeiros, assim como garantir que o utente percebeu a informação). Com menor índice de satisfação “Informação de recursos” (preocupação em envolver os familiares, informação sobre utilização de outros recursos disponíveis ou serviços de saúde). Conclusões: A satisfação é elevada, sendo a maior dificuldade apontada à inclusão de outros agentes no processo de acompanhamento e a informação de outros recursos disponíveis. Os resultados mantêm aberta a discussão sobre a melhor forma de fazer investigação sobre satisfação.

Challenges in schizoaffetive disorder therapeutic – a case report of a patient with hiperprolactinemia

Introduction

The only FDA approval therapeutic for schizoaffective disorder is paliperidone. Hiperprolactinemia is one of the most frequent side effects induced by first generation antipsychotics (FGA) or by second generation antipsychotic (SGA), such as risperidone and paliperidone. Prolactin related symptoms (PRS) include amenorrhea, galactorrhea, gynecomastia and fluctuations in psychotic symptoms.

Objectives

To report the case of a patient with schizoaffective disorder difficult to manage due to symptom resistance and PRS, that improved symptomatology when prolactin serum levels were reduced.

Methods

Clinical-demographic data collected by clinical interview and clinical process consultation. Non-systematic literature review, searching “psychosis”; “prolactin”; “antipsychotic”; “schizoaffective disorder” on Pubmed database.

Results

We report the case of 33 years-old female, admitted to our psychiatry inpatient unit for persecutory delusions, loosening of association, auditory hallucinations, and irritability with functional impairment. Symptoms began 13 years before. She was medicated with paliperidone 100mg IM monthly, lithium 800mg daily and clozapine 225mg daily. When admitted she wasn’t adhering to oral medication. On physical examination presented some PRS. The serum presented hyperprolactinemia and lithium in non-therapeutic levels. Initially was re-introduced the previous therapeutic without improval. It was made a therapeutic switch to associate aripiprazole 400mg IM monthly and clozapine 225mg daily, and lithium 800mg daily resulting in prolactine normalization and subsequent improval of psychotic symptoms previously presented.

Conclusions

This case reports challenges in management of patients diagnosed with Schizoaffetive Disorder due to therapeutic refractoriness and side effects. PRS can be ruling, therefore impacting therapeutic choices. We propose a possible role of combination of clozapine and aripiprazole in this scenario.

Disclosure

No significant relationships.

Monogenic diabetes: a new pathogenic variant of HNF1A gene

Maturity onset diabetes of the young defines a diabetes mellitus subtype, with no insulin resistance or autoimmune pancreatic β-cells dysfunction, that occurs by mutation in a single gene. A 13-year-old girl hospitalised due to hyperglycemia plus glycosuria without ketosis, and with normal glycated haemoglobin of 6.8%. She started a sugar-free fast-absorption diet and no insulin therapy was required. Fasting glucose was normal, but 2 hours after lunch she presented hyperglycemia as after 2 hours of an oral glucose tolerance test, with 217 mg/dL. Family history was positive for type 2 diabetes mellitus with an autosomal dominant pattern. She was discharged with fast-absorption sugar-free diet and low-dose of sulfonylurea. A genetic test was performed detecting a mutation in heterozygosity of HNF1A gene, compatible with the diagnosis of maturity onset diabetes of the young 3 (MODY3), not reported in the literature. Early recognition of signs and symptoms increase awareness of MODY. Genetic test allows confirmation and leads to optimised treatment.

CYP21A2 Gene Pathogenic Variants: A Multicenter Study on Genotype-Phenotype Correlation from a Portuguese Pediatric Cohort

BACKGROUND

Congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency (21OHD) is an autosomal recessive disorder characterized by 3 overlapping phenotypes: salt-wasting (SW), simple virilizing (SV), and non-classic (NC). We aimed at conducting a nationwide genotype description of the CAH pediatric patients and to establish their genotype-phenotype correlation.

METHODS

CAH patients were recruited from Portuguese pediatric endocrinology centers and classified as SW, SV, or NC. Genetic analysis was performed by polymerase chain reaction (sequence specific primer, restriction fragment length polymorphism) or direct Sanger sequencing. Genotypes were categorized into 4 groups (0, A, B, and C), according to their predicted enzymatic activity. In each group, the expected phenotype was compared to the observed phenotype to assess the genotype-phenotype correlation.

RESULTS

Our cohort comprises 212 unrelated pediatric CAH patients (29% SW, 11% SV, 60% NC). The most common pathogenic variant was p.(Val282Leu; 41.3% of the 424 alleles analyzed). The p.(Val282Leu) variant, together with c.293-13A/C>G, p.(Ile173Asn), p.(Leu308Thr), p.(Gln319*), and large deletions/conversions were responsible for 86.4% of the mutated alleles. Patients' stratification by disease subtype revealed that the most frequent pathogenic variants were c.293-13A/C>G in SW (31.1%), p.(Ile173Asn) in SV (46.9%), and p.(Val282Leu) in NC (69.5%). The most common genotype was homozygosity for p.(Val282Leu; 33.0%). Moreover, we found 2 novel variants: p.(Ile161Thr) and p.(Trp202Arg), in exons 4 and 5, respectively. The global genotype-phenotype correlation was 92.4%. Group B (associated with the SV form) showed the lowest genotype-phenotype correlation (80%).

CONCLUSION

Our cohort has one of the largest NC CAH pediatric populations described. We emphasize the high frequency of the p.(Val282Leu) variant and the very high genotype-phenotype correlation observed.

Electrophysiological evaluation of extracellular spermine and alkaline pH on synaptic human GABAA receptors

Polyamines have fundamental roles in brain homeostasis as key modulators of cellular excitability. Several studies have suggested alterations in polyamine metabolism in stress related disorders, suicide, depression, and neurodegeneration, making the pharmacological modulation of polyamines a highly appealing therapeutic strategy. Polyamines are small aliphatic molecules that can modulate cationic channels involved in neuronal excitability. Previous indirect evidence has suggested that polyamines can modulate anionic GABA_A receptors (GABA_ARs), which mediate inhibitory signaling and provide a direct route to reduce hyperexcitability. Here, we attempted to characterize the effect that spermine, the polyamine with the strongest reported effect on GABA_ARs, has on human postmortem native GABA_ARs. We microtransplanted human synaptic membranes from the dorsolateral prefrontal cortex of four cases with no history of mental or neurological disorders, and directly recorded spermine effects on ionic GABA_ARs responses on microtransplanted oocytes. We show that in human synapses, inhibition of GABA_ARs by spermine was better explained by alkalization of the extracellular solution. Additionally, spermine had no effect on the potentiation of GABA-currents by diazepam, indicating that even if diazepam binding is enhanced by spermine, it does not translate to changes in functional activity. Our results clearly demonstrate that while extracellular spermine does not have direct effects on human native synaptic GABA_ARs, spermine-mediated shifts of pH inhibit GABA_ARs. Potential spermine-mediated increase of pH in synapses in vivo may therefore participate in increased neuronal activity observed during physiological and pathological states, and during metabolic alterations that increase the release of spermine to the extracellular milieu.

A velocity tracking approach for the data assimilation problem in blood flow simulations

Several advances have been made in data assimilation techniques applied to blood flow modeling. Typically, idealized boundary conditions, only verified in straight parts of the vessel, are assumed. We present a general approach, on the basis of a Dirichlet boundary control problem, that may potentially be used in different parts of the arterial system. The relevance of this method appears when computational reconstructions of the 3D domains, prone to be considered sufficiently extended, are either not possible, or desirable, because of computational costs. On the basis of taking a fully unknown velocity profile as the control, the approach uses a discretize then optimize methodology to solve the control problem numerically. The methodology is applied to a realistic 3D geometry representing a brain aneurysm. The results show that this data assimilation approach may be preferable to a pressure control strategy and that it can significantly improve the accuracy associated to typical solutions obtained using idealized velocity profiles.

Growth performance, carcass and meat quality of lambs supplemented with increasing levels of a tanniferous bush (Cistus ladanifer L.) and vegetable oils

The effects of dietary inclusion of Cistus ladanifer L. (CL) and a vegetable oil blend were evaluated on growth performance,carcass and meat quality of fifty four lambs that were assigned to 9 diets, corresponding to 3 levels of CL(50, 100 and 200 g/kg DM) and 3 levels of oil inclusion (0, 40 and 80 g/kg DM). Treatments had no effects on growth rate. Oil depressed dry matter intake (P = 0.017), carcass muscle (P = 0.041) and increased (P = 0.016) kidney knob channel fat. Chemical and physical meat quality traits were not affected by treatments. Off-flavour perception was higher for 8% of oil (P b 0.001). The level of 100 g/kg DM of CL inclusion improved meat stability after 7 days of storage. Supplementation with linseed and soybean oils (2:1) was a good approach to improve meat nutritional value from feedlot lambs, increasing total n-3 PUFA.

Numerical validation of a synthetic cell-based model of blood coagulation

In Fasano et al. (2012) a new reduced mathematical model for blood coagulation was proposed, incorporating biochemical and mechanical actions of blood flow and including platelets activity. The model was characterized by a considerable simplification of the differential system associated to the biochemical network and it incorporated the role of blood slip at the vessel wall as an extra source of activated platelets. The purpose of this work is to check the validity of the reduced mathematical model, using as a benchmark the model presented in Anand et al. (2008), and to investigate the importance of the blood slip velocity in the blood coagulation process.

Sensitivity to outflow boundary conditions and level of geometry description for a cerebral aneurysm

Mathematical models, namely the flow boundary conditions, as well as the detail of the bounding geometry, can highly influence the computed flow field. In this work, an anatomically realistic portion of cerebral vasculature with a saccular aneurysm, and its geometric idealisation, are considered. The importance of the geometric description, namely including the side branches or modelling them as holes in the main vessel, is studied. Several approaches to prescribe the outflow boundary conditions at the side branches are analysed, including the traction-free condition, zero velocity (hence neglecting the side-branch), and the coupling with simple zero-dimensional and one-dimensional models. Results of the effects of outflow boundary modelling choice on computed haemodynamic parameters are used to identify appropriateness of the models based on the physical interpretation. Estimated range of error-bars associated to outflow boundary model choice and the level of geometric details are presented for patient-specific computational haemodynamics, and can serve as invitation for future studies. The zero-dimensional and one-dimensional models are shown to provide good representations of the side branches in the case of the clipped geometry.

Altered expression of genes involved in ATP biosynthesis and GABAergic neurotransmission in the ventral prefrontal cortex of suicides with and without major depression

The prefrontal cortex is believed to play a major role in depression and suicidal behavior through regulation of cognition, memory, recognition of emotion, and anxiety-like states, with numerous post-mortem studies documenting a prefrontal serotonergic dysregulation considered to be characteristic of depressive psychopathology. This study was carried out to detect changes in gene expression associated with both suicide and major depression using oligonucleotide microarrays (Affymetrix HG-U133 chip set) summarizing expression patterns in primarily ventral regions of the prefrontal cortex (BA44, 45, 46 and 47). A total of 37 male subjects were included in this study, of which 24 were suicides (depressed suicides=16, nondepressed suicides=8) and 13 were matched controls. All subjects were clinically characterized by means of psychological autopsies using structured interviews. Unique patterns of differential expression were validated in each of the cortical regions evaluated, with group-specific changes highlighting the involvement of several key neurobiological pathways that have been implicated in both suicide and depression. An overrepresentation of factors involved in cell cycle control and cell division (BA44), transcription (BA44 and 47) and myelination (BA46) was seen in gene ontology analysis of differentially expressed genes, which also highlights changes in the expression of genes involved in ATP biosynthesis and utilization across all areas. Gene misexpression in BA46 was most pronounced between the two suicide groups, with many significant genes involved in GABAergic neurotransmission. The pronounced misexpression of genes central to GABAergic signaling and astrocyte/oligodendrocyte function provides further support for a central glial pathology in depression and suicidal behavior.

Numerical Simulation of the Coagulation Dynamics of Blood

The process of platelet activation and blood coagulation is quite complex and not yet completely understood. Recently, a phenomenological meaningful model of blood coagulation and clot formation in flowing blood that extends existing models to integrate biochemical, physiological and rheological factors, has been developed. The aim of this paper is to present results from a computational study of a simplified version of this coupled fluid-biochemistry model. A generalized Newtonian model with shear-thinning viscosity has been adopted to describe the flow of blood. To simulate the biochemical changes and transport of various enzymes, proteins and platelets involved in the coagulation process, a set of coupled advection–diffusion–reaction equations is used. Three-dimensional numerical simulations are carried out for the whole model in a straight vessel with circular cross-section, using a finite volume semi-discretization in space, on structured grids, and a multistage scheme for time integration. Clot formation and growth are investigated in the vicinity of an injured region of the vessel wall. These are preliminary results aimed at showing the validation of the model and of the numerical code.

Localized hydrodynamics of clustering leukocytes

The recruitment of leukocytes to the endothelial walls is intensively investigated both experimentally and through three dimensional computer simulations. The shear dependent viscosity has been obtained from measured values in post-capillary venules of Wistar rats' cremaster muscle. Localized velocity fields and shear stresses on the surface of leukocytes and near vessel wall attachment points have been computed and discussed for a cluster of recruited leukocytes under generalized Newtonian blood flow with shear thinning viscosity. We have observed one region of maximum shear stress and two regions of minimum shear stress on the surface of the leukocytes close to the endothelial wall. This suggests that the accumulation of selectins attains a minimum value in two regions, rather than in one region, on the surface of the leukocytes. We have also verified that the collective hemodynamic behavior of the cluster of recruited leukocytes establishes a strong motive for additional leukocyte recruitment. From this study we claim that the influence of the leukocytes rolling on the endothelial wall increases the shear stress on both the leukocyte and the endothelial wall which results in activating more signaling mediators during inflammation.

Leukocytes rolling and recruitment by endothelial cells: hemorheological experiments and numerical simulations

The recruitment of leukocytes from the blood stream and their subsequent adhesion to endothelial walls are essential stages to the immune response system during inflammation. The precise dynamic mechanisms by which molecular mediators facilitate leukocyte arrests are still unknown. In this study combined experimental results and computer simulations are used to investigate localized hydrodynamics of individual and collective behavior of clusters of leukocytes. Leukocyte-endothelial cell interactions in post-capillary venules of Wistar rats cremaster muscle were monitored by intravital microscopy. From these experiments the hemorheologic and hemodynamical measured parameters were used in time dependent three-dimensional computer simulations, using a mesoscopic lattice Boltzmann flow solver for shear thinning fluids. The dynamics of leukocyte clusters under generalized Newtonian blood flow with shear thinning viscosity was computed and discussed. In this paper we present quantified distributions of velocity and shear stress on the surface of leukocytes and near vessel wall attachment points. We have observed one region of maximum shear stress and two regions of minimum shear stress on the surface of leukocytes close to the endothelial wall. We verified that the collective hydrodynamic behavior of the cluster of recruited leukocytes establishes a strong motive for additional leukocyte recruitment. It was found that the lattice Boltzmann solver used here is fully adaptive to the measured experimental parameters. This study suggests that the influence of the leukocytes rolling on the increase of the endothelial wall shear stress may support the activation of more signalling mediators during inflammation.

Patterns of gene expression in the limbic system of suicides with and without major depression

The limbic system has consistently been associated with the control of emotions and with mood disorders. The goal of this study was to identify new molecular targets associated with suicide and with major depression using oligonucleotide microarrays in the limbic system (amygdala, hippocampus, anterior cingulate gryus (BA24) and posterior cingulate gyrus (BA29)). A total of 39 subjects were included in this study. They were all male subjects and comprised 26 suicides (depressed suicides=18, non depressed suicides=8) and 13 matched controls. Brain gene expression analysis was carried out on human brain samples using the Affymetrix HG U133 chip set. Differential expression in each of the limbic regions showed group-specific patterns of expression, supporting particular neurobiological mechanisms implicated in suicide and depression. Confirmation of genes selected based on their significance and the interest of their function with reverse transcriptase-polymerase chain reaction showed consistently correlated signals with the results obtained in the microarray analysis. Gene ontology analysis with differentially expressed genes revealed an overrepresentation of transcription and metabolism-related genes in the hippocampus and amygdala, whereas differentially expressed genes in BA24 and BA29 were more generally related to RNA-binding, regulation of enzymatic activity and protein metabolism. Limbic expression patterns were most extensively altered in the hippocampus, where processes related to major depression were associated with altered expression of factors involved with transcription and cellular metabolism. Additionally, our results confirm previous evidence pointing to global alteration of gabaergic neurotransmission in suicide and major depression, offering new avenues in the study and possibly treatment of such complex disorders. Overall, these data suggest that specific patterns of expression in the limbic system contribute to the etiology of depression and suicidal behaviors and highlight the role of the hippocampus in major depression.

A large splenic cyst mimicking diabetic gastroparesis

Splenic cysts are rare, many of which are asymptomatic and incidental finding. We report an interesting case of a large incidental splenic cyst in a young diabetic patient who presented with diabetic ketoacidosis and mimicking gastroparesis. The differential diagnosis and management of splenic cysts is discussed.

Suicide and serotonin: study of variation at seven serotonin receptor genes in suicide completers

Suicide is an important public health problem, accounting for a significant proportion of total mortality among young people, particularly males. There is growing and consistent evidence suggesting that genetic factors play an important role in the predisposition to suicide. Based on several lines of evidence supporting a reduced serotonergic neurotransmission in subjects who committed suicide, we investigated variation at genes that code for serotonin receptor 1B (5-HTR1B), 1Dalpha (5-HTR1Dalpha), 1E (5-HTR1E), 1F (5-HTR1F), 2C (5-HTR2C), 5A (5-HTR5A), and 6 (5-HTR6) in a total sample of 106 suicide completers and 120 normal controls. No differences were observed in allelic or genotypic distributions between groups for any of the loci investigated. Moreover, further analysis according to suicide method or psychopathology also failed to reveal differences between groups. Our results do not support a substantial role of these serotonergic receptors in suicide completion.

Evidence for a genetic association between monoamine oxidase A and restless legs syndrome

BACKGROUND

Impairment in the central dopaminergic system has been consistently suggested as an etiologic factor in restless legs syndrome (RLS).

OBJECTIVE

To investigate a possible role for the MAOA and MAOB genes in RLS using a population-based association study.

METHODS

In addition to a dinucleotide repeat located within the second intron of the MAOB gene, a functional variable number of tandem repeat (VNTR) polymorphism recently identified in the MAOA gene promoter region was examined, using 96 extensively characterized patients and 200 control subjects matched for ethnic background. The relationship between variation at these loci and several clinical features was also considered.

RESULTS

Pertaining to the MAOA gene, females with the high activity allele had a greater risk (OR: 2.0; 95% CI: 1.06 to 3.77) of being affected with RLS than females carrying the low activity alleles. The authors did not observe this association among the male subjects (OR: 0.98; 95% CI: 0.31 to 3.14). Interestingly, females carrying the high transcription alleles showed a longer sleep onset latency (U = 163.5; p = 0.015) and exhibited a higher movement index during the Suggested Immobilization Test (Student's t-test = -2.02; p = 0.048). No differences were observed regarding the MAOB gene in our sample.

CONCLUSIONS

The high activity allele of the MAOA gene may represent a modifying factor involved in the severity of RLS manifestations in females.

Genetic diversity among isolates of Trichinella spiralis from the Province of Buenos Aires, Argentina

Random Amplified Polymorphic DNAs, (RAPDs) are used to study the occurrence of Trichinella britovi and T5 among domestic animals in the Province of Buenos Aires, Argentina and to assess the genetic diversity among isolates of T. spiralisfrom this area in a number of infected hosts. All the local isolates proved to be T. spiralis. Six of the eight primers used indicate that the Buenos Aires isolates are distinct from each other as they produce a considerable number of polymorphic bands. Our overall estimates are relatively higher than other intraspecific distances previously estimated within species of this genus and among T. spiralis isolates. Such high degrees of variability observed among local isolates and between isolates from Buenos Aires and Spain should be taken into account when defining isolates within this species, and considering differences in the epidemiology of T. spiralis.

Apparent dopamine D1 and D2 receptors in the weaver mutant mouse: receptor binding and coupling to adenylyl cyclase

Weaver mutant mice have a selective degeneration of the nigrostriatal dopamine pathway arising between 7-21 days after birth. The goal of this study was to investigate the effects of this mutation on different parameters of the nigrostriatal and mesolimbic dopamine system: apparent D1 and D2 receptor binding sites as well as their signal transduction pathway. Using quantitative autoradiography of ligands for dopamine D1, D2 receptors and the dopamine uptake site, we found a significant loss in apparent D1 receptor binding sites throughout the neostriatum, significant increase of apparent D2 receptor binding in the dorsal aspect of the neostriatum, and almost complete loss of DA uptake sites in these regions of the weaver mouse. In contrast to the neostriatum, the density of dopamine receptors and uptake sites in the nucleus accumbens of the weaver mouse did not differ from controls. Despite alterations in the binding of apparent D1 and D2 receptors, there was no significant difference in either basal, DA stimulated or GTPgammaS stimulated cAMP production. These findings suggest the down-regulation of apparent D1 receptor binding sites reported in this model, probably does not reflect an important physiological mechanism through which these animals compensate for loss of dopamine innervation.

[The influence of therapy (sympathomimetic amines versus vasodilators) in the indexes of ejection fraction derived from an analysis of Doppler aortic flow]

PURPOSE

To assess the influence of inotropic IV therapy--dobutamine and/or dopamine--versus vasodilator therapy--nitroprusside, captopril or hydralazine--in aortic flow ejection phase indexes obtained by pulsed Doppler echocardiography.

METHODS

In 17 patients admitted to the ICU (11 males, 62 +/- 14 years, 9 with ischemic cardiomyopathy and 8 with dilated cardiomyopathy, all in sinus rhythm), with congestive heart failure, and submitted to tailored therapy, 53 serial pulsed Doppler and hemodynamic evaluations were made as the therapy changed the hemodynamic and clinical status. Considering serial consecutive evaluations, a hemodynamic improvement was obtained only with inotropics in 13 (group A), and with vasodilators in only 15 (group B). The following ejection phase indexes were calculated from Doppler registers: average acceleration (AvAc) and ejection force (EFor), calculated according to the formula: Efor = 1.06 x Aortic Orifice Area x AvAc x Acceleration Velocity Time Integral.

RESULTS

Arterial blood pressure increased in gr A (76.2 +/- 14.1 to 81.4 +/- 14.8 mm Hg, p < 0.05) and decreased in gr B (85.1 +/- 12.6 to 76.2 +/- 9.7 mm Hg (p < 0.05). In both groups there was a significant (p < 0.05) increase in cardiac output (CO)-from 3.9 +/- 1.1 to 4.9 +/- 1.4 L/min in group A, and from 3.9 +/- 1.2 to 4.4 +/- 1.2 L/min in group B. CO increased 18.7% in group A and 13.8% in group B (NS). There was a decrease in pulmonary capillary wedge pressure (PCWP) from 19.5 +/- 6.0 to 15.1 +/- 5.8 mm Hg in group A (p < 0.05), and from (16.9 +/- 5.7 to 12.1 +/- 4.6 mm Hg in group B (p < 0.05). PCWP decreased 19.7% in group A and 27.8% in group B (NS). Systemic vascular resistance (SVR) changed from 18.2 +/- 7.0 to 16.2 +/- 7.1 Wood U in group A (p < 0.05), and from 22.3 +/- 9.3 to 17.7 +/- 5.7 Wood U in group B (p < 0.05). In group A, AvAc increased-from 1347 +/- 611 cm.s-2 (p < 0.05), as did Efor-from 15.4 +/- 10.7 to 20.2 +/- 11.0 g.cm,s-2 (p < 0.05), whereas in group B there was no significant change in either AvAc-from 1337 +/- 284 to 1277 +/- 256 cm.s-2, or Efor-from 22.7 +/- 17.0 to 23.8 +/- 15.0 g.cm.s-2.

CONCLUSIONS

Vasodilator therapy, although inducing hemodynamic changes similar to inotropics, does not alter the ejection phase indexes. Therefore, AvAc and Efor, in spite of being calculated from the aortic flow, are independent of the changes in PCWP and SVR and seem to reflect changes in inotropism in the clinical setting.

Cation disorder in ferroelectric PbBi2Nb2O9

The ferroelectric Curie temperature, Tc , of PbBi2Nb2O9 was found to shift from 833 K in samples slowly cooled from 1373 K to Tc 's up to 883 K when the samples were quenched from various temperatures in the range 973–1373 K. The variation of Tc with heat treatment was fully reversible. Extra Raman modes appear and the width of some Raman bands change as a function of heat treatment. These results are interpreted in terms of cation order–disorder involving the Pb2+ and Bi3+ ions in the perovskite units and the Bi2O2 layer. Neutron Rietveld analyses of the structures (orthorhombic, A21 am, Z = 4, λ = 1.216) indicate a possible change in cationic order–disorder, with Pb2+ ions preferentially occupying the perovskite A-sites to the extent of 91 (7) and 80 (7)%, respectively, in the quenched and slowly cooled samples.

[The QTc interval and its dispersion in hypertrophic myocardiopathy--its relation to complex ventricular arrhythmias and the effect of anti-arrhythmia agents]

The aim of the present study was to evaluate, in patients with hypertrophic cardiomyopathy (HCM): 1. The relation of rate corrected QT interval (QTc) and of QTc interlead variability (QTc dispersion) to complex ventricular arrhythmias (CVA); 2. The effects of amiodarone (Am), beta-blockers (beta B) and calcium antagonists (CA) on QTc and on QTc dispersion. Surface 12 leads ECG was analysed in 55 patients with HCM (39 +/- 12 years, 32 males). All patients were in sinus rhythm, without bundle branch block. Maximum (max), minimum (min) and mean QTc values were considered. QTc dispersion was calculated as: a) max QTc - min QTc (max-min); b) dispersion index (DI) = standard deviation of QTc/mean QTcx100. Patients groups were defined accordingly to: 1--the absence (group A1-35 patients) or the presence (group A2-20 patients) of CVA on 24 hours Holter monitoring; II--absence of cardioactive medication (group B1-20 patients) versus monotherapy with Am (group B3-10 patients), or beta B (group B4-15 patients), or CA (group B5-10 patients). Age, gender, type of HCM (asymmetric versus concentric) and echocardiographic fractional shortening were not different in the studied groups.

RESULTS

[table: see text]

CONCLUSIONS

1. Maximum QTc interlead QTc dispersion are increased in patients with HCM that show CVA on Holter monitoring; 2. Amiodarone prolongs QTc but reduces QTc dispersion, while beta-blockers and calcium antagonists do not significantly change neither the duration nor the dispersion of ventricular repolarization.

Molecular characterization of the variable regions of a mouse polyreactive IgG2b antibody with rheumatoid factor activity

The complete nucleotide sequences of heavy and light chains of a mouse polyreactive IgG2b antibody were determined. This antibody, obtained after primary immunization of BALB/c mice with human lymphoblastoid cells, possess anti-HLA-DR and anti-rheumatoid factor activities and reacts with various self and nonself antigens. The VL and VH segments were found to belong to the VK8 and VH7183 families, respectively. The VH segment shared a high percentage of sequence similarity (95%) with previously described germline genes. The VK segment had 98.9% of sequence similarity with a consensus sequence VK8 of antibodies with anti-phosphorylcholine activity. Furthermore, the framework regions 2 and 3 of the VL segment were very similar to the framework regions 2 and 3 of other antibodies known to possess rheumatoid factor activity. We postulate that during immunization, the presence of HLA-DR antigens selects precursors having configurations similar to that of the germline, and induces some somatic mutations that do not significantly affect antibody polyreactivity.

Multiple small-angle scattering from a statistical medium

A generalized formalism on multiple small-angle scattering is proposed to investigate the nature of the extractable structural information on inhomogeneities from the multiple-scattering profile. It is found that the statistical nature of the medium can broaden as well as narrow the scattering profile depending upon the characteristics of the medium. The nature and the extent of the effect of the various approximations on analysing the multiple-scattering data are discussed.

Characterization of a murine immunoglobulin VH gene segment in subgroup III: a new member of the 7183 gene family

A new gene for the variable region of the immunoglobulin heavy chain (VH gene) has been isolated from BALB/c adult liver DNA using a cDNA plasmid probe containing a mouse VH sequence. The complete nucleotide sequence of this germline gene (VH10-19), shows that it belongs to the 7183 gene family. The VH gene appears to contain an intervening 104-base-long sequence and displays the same recombination signal sequences that those observed in the germline 81X. The presence of an internal heptamer at the 3' end of the VH10-19 coding region let an alternative recombination event that could increase the representation of this gene in the immature repertoire.