Cell Intrinsic Determinants of Alpha Herpesvirus Latency and Pathogenesis in the Nervous System

Alpha herpesvirus infections (α-HVs) are widespread, affecting more than 70% of the adult human population. Typically, the infections start in the mucosal epithelia, from which the viral particles invade the axons of the peripheral nervous system. In the nuclei of the peripheral ganglia, α-HVs establish a lifelong latency and eventually undergo multiple reactivation cycles. Upon reactivation, viral progeny can move into the nerves, back out toward the periphery where they entered the organism, or they can move toward the central nervous system (CNS). This latency-reactivation cycle is remarkably well controlled by the intricate actions of the intrinsic and innate immune responses of the host, and finely counteracted by the viral proteins in an effort to co-exist in the population. If this yin-yang- or Nash-equilibrium-like balance state is broken due to immune suppression or genetic mutations in the host response factors particularly in the CNS, or the presence of other pathogenic stimuli, α-HV reactivations might lead to life-threatening pathologies. In this review, we will summarize the molecular virus-host interactions starting from mucosal epithelia infections leading to the establishment of latency in the PNS and to possible CNS invasion by α-HVs, highlighting the pathologies associated with uncontrolled virus replication in the NS.

Interferon-λ Activates a Differential Response in Peripheral Neurons That Is Effective against Alpha Herpesvirus Infections

Alpha herpesviruses (α-HV) infect host mucosal epithelial cells prior to establishing a life-long latent infection in the peripheral nervous system. The initial spread of viral particles from mucosa to the nervous system and the role of intrinsic immune responses at this barrier is not well understood. Using primary neurons cultured in compartmentalized chambers, prior studies performed on Pseudorabies virus (PRV) have demonstrated that type I and type II interferons (IFNs) induce a local antiviral response in axons via distinct mechanisms leading to a reduction in viral particle transport to the neuronal nucleus. A new class of interferons known as type III IFNs has been shown to play an immediate role against viral infection in mucosal epithelial cells. However, the antiviral effects of type III IFNs within neurons during α-HV infection are largely unknown. In this study, we focused on elucidating the antiviral activity of type III IFN against PRV neuronal infection, and we compared the interferon-stimulated gene (ISGs) induction pattern in neurons to non-neuronal cells. We found that IFN pre-exposure of both primary neurons and fibroblast cells significantly reduces PRV virus yield, albeit by differential STAT activation and ISG induction patterns. Notably, we observed that type III IFNs trigger the expression of a subset of ISGs mainly through STAT1 activation to induce an antiviral state in primary peripheral neurons.

Definition of unconformities based on radiometric tool

The concentrations of U-238, Th-232, and K-40 measured with a portable gamma-ray spectrometer in cutting samples of two exploratory wells allowed the radiometric characterization of Cretaceous Rancheria sub-basin rocks and the definition of twelve (12) zones according to paleo-redox facies. The Th/Ua (authigenic uranium) and Th/U ratio greater than 7 (seven) indicates paleo-redox conditions related to oxygenation changes and detrital material input during deposition and terrestrial freshwater environment. However, the Lagunitas, Aguas Blancas, La Luna, and Molino formations characterize by facies from sub-oxic (dioxic) to anoxic redox. In the Aguas Blancas and Molino Formations, pyrite and the high uranium measurements determine an anoxic and euxinic environment. The high values of both + uranium and authigenic uranium in the La Luna and Molino formations relate to the conservation of organic matter, which is an essential factor in the generation of hydrocarbons. The abrupt changes of both K/U and Th/U identify potential sequential or genetic limit surfaces (e.g., maximum flooding surfaces), limiting such zones. Based on radiometric behavior, this research permitted identifying eight Cretaceous to Miocene unconformities in the area, three of them reported here for the first time.

Black and Latinx Primary Caregiver Considerations for Developing and Implementing a Machine Learning-Based Model for Detecting Child Abuse and Neglect With Implications for Racial Bias Reduction: Qualitative Interview Study With Primary Caregivers

BACKGROUND

Child abuse and neglect, once viewed as a social problem, is now an epidemic. Moreover, health providers agree that existing stereotypes may link racial and social class issues to child abuse. The broad adoption of electronic health records (EHRs) in clinical settings offers a new avenue for addressing this epidemic. To reduce racial bias and improve the development, implementation, and outcomes of machine learning (ML)-based models that use EHR data, it is crucial to involve marginalized members of the community in the process.

OBJECTIVE

This study elicited Black and Latinx primary caregivers' viewpoints regarding child abuse and neglect while living in underserved communities to highlight considerations for designing an ML-based model for detecting child abuse and neglect in emergency departments (EDs) with implications for racial bias reduction and future interventions.

METHODS

We conducted a qualitative study using in-depth interviews with 20 Black and Latinx primary caregivers whose children were cared for at a single pediatric tertiary-care ED to gain insights about child abuse and neglect and their experiences with health providers.

RESULTS

Three central themes were developed in the coding process: (1) primary caregivers' perspectives on the definition of child abuse and neglect, (2) primary caregivers' experiences with health providers and medical documentation, and (3) primary caregivers' perceptions of child protective services.

CONCLUSIONS

Our findings highlight essential considerations from primary caregivers for developing an ML-based model for detecting child abuse and neglect in ED settings. This includes how to define child abuse and neglect from a primary caregiver lens. Miscommunication between patients and health providers can potentially lead to a misdiagnosis, and therefore, have a negative impact on medical documentation. Additionally, the outcome and application of the ML-based models for detecting abuse and neglect may cause additional harm than expected to the community. Further research is needed to validate these findings and integrate them into creating an ML-based model.

Developing machine learning-based models to help identify child abuse and neglect: key ethical challenges and recommended solutions

Child abuse and neglect are public health issues impacting communities throughout the United States. The broad adoption of electronic health records (EHR) in health care supports the development of machine learning-based models to help identify child abuse and neglect. Employing EHR data for child abuse and neglect detection raises several critical ethical considerations. This article applied a phenomenological approach to discuss and provide recommendations for key ethical issues related to machine learning-based risk models development and evaluation: (1) biases in the data; (2) clinical documentation system design issues; (3) lack of centralized evidence base for child abuse and neglect; (4) lack of "gold standard "in assessment and diagnosis of child abuse and neglect; (5) challenges in evaluation of risk prediction performance; (6) challenges in testing predictive models in practice; and (7) challenges in presentation of machine learning-based prediction to clinicians and patients. We provide recommended solutions to each of the 7 ethical challenges and identify several areas for further policy and research.

Considerations for development of child abuse and neglect phenotype with implications for reduction of racial bias: a qualitative study

OBJECTIVE

The study provides considerations for generating a phenotype of child abuse and neglect in Emergency Departments (ED) using secondary data from electronic health records (EHR). Implications will be provided for racial bias reduction and the development of further decision support tools to assist in identifying child abuse and neglect.

MATERIALS AND METHODS

We conducted a qualitative study using in-depth interviews with 20 pediatric clinicians working in a single pediatric ED to gain insights about generating an EHR-based phenotype to identify children at risk for abuse and neglect.

RESULTS

Three central themes emerged from the interviews: (1) Challenges in diagnosing child abuse and neglect, (2) Health Discipline Differences in Documentation Styles in EHR, and (3) Identification of potential racial bias through documentation.

DISCUSSION

Our findings highlight important considerations for generating a phenotype for child abuse and neglect using EHR data. First, information-related challenges include lack of proper previous visit history due to limited information exchanges and scattered documentation within EHRs. Second, there are differences in documentation styles by health disciplines, and clinicians tend to document abuse in different document types within EHRs. Finally, documentation can help identify potential racial bias in suspicion of child abuse and neglect by revealing potential discrepancies in quality of care, and in the language used to document abuse and neglect.

CONCLUSIONS

Our findings highlight challenges in building an EHR-based risk phenotype for child abuse and neglect. Further research is needed to validate these findings and integrate them into creation of an EHR-based risk phenotype.

Evaluation of naturally occurring radioactive materials (NORM) in the soil, in a potential area for unconventional reservoirs in the Rancheria Sub-Basin

Naturally occurring radioactive elements depend on lithology geogenic characteristics, such as depositional, environmental, or diagenetic. Thus, evaluating these elements constitutes a tool to define ionizing radiation effect from rocky sequences. This study carried out in the Rancheria Sub-Basin establishes both characterization and assessment of this kind of material, known as NORM. The sampling included uranium-238, thorium-232, potassium-40, radon-226, and radon-222 in soil samples, cutting samples from the Molino-1 well, and radon in surface water. Bases on a radiometric methodology with a gamma-ray spectrometer for uranium-238, thorium-232, and potassium-40 and emanometric with ionizing chambers for radio-226 and radon-222. The analysis and results of the activity concentrations in soil samples of U-238, Th-232, K-40, and Ra-226 are 11.7 BqKg^-1, 33.0 BqKg^-1, 424.5 BqKg^-1, and 15.59 BqKg^-1, respectively, among the acceptable global averages. However, in some areas, observed values indicate high activity concentrations of U-238, Th-232, K-40, Ra-226, and Rn-222 in the soil of 50.2 BqKg^-1, 62.8 BqKg^-1, 1596.3 BqKg^-1, 44.25 BqKg^-1, and 112546.79 Bqm^-3, respectively. Those activity concentrations were associated with zone lithology.

An epistatic interaction between pre-natal smoke exposure and socioeconomic status has a significant impact on bronchodilator drug response in African American youth with asthma

BACKGROUND

Asthma is one of the leading chronic illnesses among children in the United States. Asthma prevalence is higher among African Americans (11.2%) compared to European Americans (7.7%). Bronchodilator medications are part of the first-line therapy, and the rescue medication, for acute asthma symptoms. Bronchodilator drug response (BDR) varies substantially among different racial/ethnic groups. Asthma prevalence in African Americans is only 3.5% higher than that of European Americans, however, asthma mortality among African Americans is four times that of European Americans; variation in BDR may play an important role in explaining this health disparity. To improve our understanding of disparate health outcomes in complex phenotypes such as BDR, it is important to consider interactions between environmental and biological variables.

RESULTS

We evaluated the impact of pairwise and three-variable interactions between environmental, social, and biological variables on BDR in 233 African American youth with asthma using Visualization of Statistical Epistasis Networks (ViSEN). ViSEN is a non-parametric entropy-based approach able to quantify interaction effects using an information-theory metric known as Information Gain (IG). We performed analyses in the full dataset and in sex-stratified subsets. Our analyses identified several interaction models significantly, and suggestively, associated with BDR. The strongest interaction significantly associated with BDR was a pairwise interaction between pre-natal smoke exposure and socioeconomic status (full dataset IG: 2.78%, p = 0.001; female IG: 7.27%, p = 0.004)). Sex-stratified analyses yielded divergent results for females and males, indicating the presence of sex-specific effects.

CONCLUSIONS

Our study identified novel interaction effects significantly, and suggestively, associated with BDR in African American children with asthma. Notably, we found that all of the interactions identified by ViSEN were "pure" interaction effects, in that they were not the result of strong main effects on BDR, highlighting the complexity of the network of biological and environmental factors impacting this phenotype. Several associations uncovered by ViSEN would not have been detected using regression-based methods, thus emphasizing the importance of employing statistical methods optimized to detect both additive and non-additive interaction effects when studying complex phenotypes such as BDR. The information gained in this study increases our understanding and appreciation of the complex nature of the interactions between environmental and health-related factors that influence BDR and will be invaluable to biomedical researchers designing future studies.

Upregulation of Multiple CD8+ T Cell Exhaustion Pathways Is Associated with Recurrent Ocular Herpes Simplex Virus Type 1 Infection

A large proportion of the world's population harbors latent HSV type 1 (HSV-1). Cross-talk between antiviral CD8⁺ T cells and HSV-1 appear to control latency/reactivation cycles. We found that compared with healthy asymptomatic individuals, in symptomatic (SYMP) patients, the CD8⁺ T cells with the same HLA-A*0201-restricted HSV-1 epitope specificities expressed multiple genes and proteins associated to major T cell exhaustion pathways and were dysfunctional. Blockade of immune checkpoints with anti-LAG-3 and anti-PD-1 antagonist mAbs synergistically restored the frequency and function of antiviral CD8⁺ T cells, both 1) ex vivo, in SYMP individuals and SYMP HLA-A*0201 transgenic mice; and 2) in vivo in HSV-1-infected SYMP HLA-A*0201 transgenic mice. This was associated with a significant reduction in virus reactivation and recurrent ocular herpetic disease. These findings confirm antiviral CD8⁺ T cell exhaustion during SYMP herpes infection and pave the way to targeting immune checkpoints to combat recurrent ocular herpes.

High Frequency of Gamma Interferon-Producing PLZFloRORγtlo Invariant Natural Killer 1 Cells Infiltrating Herpes Simplex Virus 1-Infected Corneas Is Associated with Asymptomatic Ocular Herpesvirus Infection

Invariant natural killer (iNKT) cells are among the first innate immune cells to elicit early protective immunity that controls invading viral pathogens. The role of the iNKT cell subsets iNKT1, iNKT2, and iNKT17 in herpesvirus immunity remains to be fully elucidated. In this study, we examined the protective role of cornea-resident iNKT cell subsets using the mouse model of ocular herpesvirus infection and disease. Wild-type (WT) C57BL/6 (B6) mice and CD1d knockout (KO) mice were infected ocularly with herpes simplex virus 1 (HSV-1) (strain McKrae). Cornea, spleen, and liver were harvested at 0, 2, 5, 8, and 14 days postinfection (p.i.), and the frequency and function of the three major iNKT cell subsets were analyzed and correlated with symptomatic and asymptomatic corneal herpesvirus infections. The profiles of 16 major pro- and anti-inflammatory cytokines were analyzed in corneal lysates using Western blot and Luminex assays. Early during ocular herpesvirus infection (i.e., day 2), the gamma interferon (IFN-γ)-producing PLZFloRORγtlo (promyelocytic leukemia zinc finger, retinoic acid-related orphan receptor gT) iNKT1 cell subset was the predominant iNKT cell subset in infected asymptomatic corneas. Moreover, compared to the asymptomatic corneas of HSV-1-infected WT mice, the symptomatic corneas CD1d KO mice, with iNKT cell deficiency, had increased levels of the inflammatory cytokine interleukin-6 (IL-6) and decreased levels of IL-12, IFN-γ, and the JAK1, STAT1, NF-κB, and extracellular signal-regulated kinase 1/2 (ERK1/2) pathways. Our findings suggest that IFN-γ-producing PLZFloRORγtlo iNKT1 cells play a role in the protective innate immune response against symptomatic ocular herpes.IMPORTANCE We investigated the protective role of iNKT cell subsets in asymptomatic ocular herpesvirus infection. We found that early during ocular herpesvirus infection (i.e., on day 2 postinfection), IFN-γ-producing PLZFloRORγtlo iNKT1 cells were the predominant iNKT cell subset in infected corneas of asymptomatic B6 mice (with little to no corneal herpetic disease), compared to corneas of symptomatic mice (with severe corneal herpetic disease). Moreover, compared to asymptomatic corneas of wild-type (WT) B6 mice, the symptomatic corneas of CD1d KO mice, which lack iNKT cells, showed (i) decreases in the levels of IFN-γ and IL-12, (ii) an increase in the level of the inflammatory cytokine IL-6; and (iii) downregulation of the JAK1, STAT1, NF-κB, and ERK1/2 pathways. The findings suggest that early during ocular herpesvirus infection, cornea-resident IFN-γ-producing PLZFloRORγtlo iNKT1 cells provide protection from symptomatic ocular herpes.

The Michigan Peer-to-Peer Depression Awareness Program: School-Based Prevention to Address Depression Among Teens

OBJECTIVE

The Peer-to-Peer Depression Awareness Program (P2P) is a school-based program that aims to decrease mental illness and promote well-being among students by empowering high school students as both learners and educators. Specific goals include improving the school climate around mental health, directing students to resources, and encouraging help-seeking behavior.

METHODS

In the 2015-2016 academic year, 121 students across 10 high schools organized into teams and were trained to develop and implement peer-to-peer depression awareness campaigns. Outcomes were assessed via pre- and posttest questionnaires.

RESULTS

A total of 878 students completed questionnaires. Outcomes demonstrated improved knowledge and attitudes toward depression, increased confidence in identifying and referring peers with depression, improved help-seeking intentions, and reduced stigma.

CONCLUSIONS

The P2P program increased depression literacy through the use of youth-designed and youth-implemented depression awareness and outreach activities, which may ultimately result in earlier detection of depression and in fewer depression sequelae.

Evaluation of the foetal time to death in mice after application of direct and indirect euthanasia methods

Directive 2010/63/EU on the protection of animals used for scientific purposes requires that the killing of mammal foetuses during the last third of their gestational period should be accomplished through effective and humane methods. The fact that murine foetuses are resistant to hypoxia-mediated euthanasia renders the current euthanasia methods ineffective or humane for the foetuses when these methods are applied to pregnant female mice. We have assessed the time to death of foetuses after performing either indirect (dam euthanasia) or direct (via intraplacental injection--a new approach to euthanasia) euthanasia methods in order to determine a euthanasia method that is appropriate, ethical and efficient for the killing of mouse foetuses. The respective times to death of foetuses after performing the three most commonly used euthanasia methods (namely cervical dislocation, CO2inhalation and intraperitoneal sodium pentobarbital administration) were recorded. Absence of foetal heartbeat was monitored via ultrasound. We consider that the most effective and humane method of foetal euthanasia was the one able to achieve foetal death within the shortest possible period of time. Among the indirect euthanasia methods assessed, the administration of a sodium pentobarbital overdose to pregnant female mice was found to be the fastest for foetuses, with an average post-treatment foetal death of approximately 29.8 min. As for the direct euthanasia method assessed, foetal time to death after intraplacental injection of sodium pentobarbital was approximately 14 min. Significant differences among the different mouse strains employed were found. Based on the results obtained in our study, we consider that the administration of a sodium pentobarbital overdose by intraplacental injection to be an effective euthanasia method for murine foetuses.

Spinal cord injury sequelae alter drug pharmacokinetics: an overview

STUDY DESIGN

Literature review.

OBJECTIVES

Critical review of the literature published on the physiological alterations caused by spinal cord injury (SCI) and their effect on the pharmacokinetic parameters of commonly employed drugs. The review introduces the most recent treatment protocols of a variety of drugs, enabling the modern clinician to apply efficacious and cost-effective solutions to the pharmacological treatment of SCI patients.

METHODS

Studies published in international indexed journals up to January 2011 were selected from the PubMed database.

RESULTS

The review evaluated the sequelae of SCI and their effect on pharmacological processes. The results demonstrated that these alterations affected the pharmacokinetics of drugs commonly administered to SCI patients, such as antibiotics, muscle relaxants, immunosuppressants and analgesics.

CONCLUSION

There are multiple etiologies to SCI and patients present with varying degrees of impairment. Factors such as level of injury and completeness of the injury create a very heterogeneous population within the SCI community. The heterogeneity of this population creates a problem when trying to standardize pharmacokinetic (PK) parameters. It is because of this that specific physiological alterations must be linked to changes in PK and be identified within the clinical setting. This relationship between physiology and PK enables the clinician to be alert for possible pharmacological complications in individual patients based on their clinical manifestations. Future research should aim to develop rigorous therapeutic guidelines tailored to the diverse manifestations of SCI so as to provide effective, affordable and safe pharmacotherapy.

Therapeutic efficacy of unilateral subthalamotomy in Parkinson's disease: results in 89 patients followed for up to 36 months

BACKGROUND

Stereotactic thermocoagulative lesions of the subthalamic nucleus (STN) have been shown to induce significant motor improvement in patients with Parkinson's disease (PD).

PATIENTS AND METHODS

89 patients with PD were treated with unilateral subthalamotomy. 68 patients were available for evaluations after 12 months, 36 at 24 months and 25 at 36 months.

RESULTS

The Unified Parkinson's Disease Rating Scale (UPDRS) motor scores improved significantly contralaterally to the lesion in the "off" and "on" states throughout the follow-up, except for the "on" state at the last evaluation. Axial features and signs ipsilateral to the lesion progressed steadily throughout the study. Levodopa daily doses were significantly reduced by 45%, 36% and 28% at 12, 24 and 36 months post-surgery. 14 patients (15%) developed postoperative hemichorea-ballism which required pallidotomy in eight. These 14 patients had significantly higher dyskinesia scores (levodopa induced) preoperatively than the entire cohort.

CONCLUSION

Unilateral subthalamotomy was associated with significant and sustained motor benefit contralateral to the lesion. Further work is needed to ascertain what factors led to severe, persistent chorea-ballism in a subset of patients. Subthalamotomy may be considered an option in circumstances when deep brain stimulation is not viable.

Lepidium meyenii (Maca) increases litter size in normal adult female mice

BACKGROUND

Lepidium meyenii, known as Maca, grows exclusively in the Peruvian Andes over 4000 m altitude. It has been used traditionally to increase fertility. Previous scientific studies have demonstrated that Maca increases spermatogenesis and epididymal sperm count. The present study was aimed to investigate the effects of Maca on several fertility parameters of female mice at reproductive age.

METHODS

Adult female Balb/C mice were divided at random into three main groups: i) Reproductive indexes group, ii) Implantation sites group and iii) Assessment of uterine weight in ovariectomized mice. Animals received an aqueous extract of lyophilized Yellow Maca (1 g/Kg BW) or vehicle orally as treatment. In the fertility indexes study, animals received the treatment before, during and after gestation. The fertility index, gestation index, post-natal viability index, weaning viability index and sex ratio were calculated. Sexual maturation was evaluated in the female pups by the vaginal opening (VO) day. In the implantation study, females were checked for implantation sites at gestation day 7 and the embryos were counted. In ovariectomized mice, the uterine weight was recorded at the end of treatment.

RESULTS

Implantation sites were similar in mice treated with Maca and in controls. All reproductive indexes were similar in both groups of treatment. The number of pups per dam at birth and at postnatal day 4 was significantly higher in the group treated with Maca. VO day occurred earlier as litter size was smaller. Maca did not affect VO day. In ovariectomized mice, the treatment with Maca increased significantly the uterine weights in comparison to their respective control group.

CONCLUSION

Administration of aqueous extract of Yellow Maca to adult female mice increases the litter size. Moreover, this treatment increases the uterine weight in ovariectomized animals. Our study confirms for the first time some of the traditional uses of Maca to enhance female fertility.

Evaluation of estrogenic effects of municipal effluents to the freshwater mussel Elliptio complanata

Municipal effluents are an important source of estrogens to the aquatic environment. The purpose of this study was to examine the estrogenicity of municipal effluents to the indigenous freshwater mussel, Elliptio complanata. First, estradiol-binding sites in gonad homogenates were characterized to determine the binding affinity and specificity of estrogens. Mussels were exposed to increasing concentrations of a municipal effluent for 96 h at 15 degrees C. In another experiment, mussels were placed in cages and submerged for 62 days at 1.5 km upstream and 5 km downstream of a municipal effluent plume in the St. Lawrence River. Mussels were harvested for assessment of vitellogenin-like proteins in the hemolymph and determination of total lipid, carbohydrate and protein in the gonad. The presence of specific estrogen-binding sites was found in both male and female gonads. Binding of estradiol to cytosol proteins reached saturation, yielding a dissociation constant of 0.4 nM. Vitellogenin (Vg) levels increased significantly in both the hemolymph and the gonad after exposure to the effluent. Moreover, females appeared to be more sensitive than males to producing Vg. Mussels exposed in situ to contaminated surface waters had higher levels of Vg at the downstream site, again, females had higher levels of Vg than did males. On the other hand, lipid and sugar levels in male gonads were significantly increased at the downstream site. Moreover, mussels at the downstream site had decreased shell growth length and increased total and soft tissue weights. We conclude that municipal effluents contain bio-available xenoestrogens at levels sufficient to elicit effects in freshwater mussels.

Clinical findings in a patient mosaic for a supernumerary ring chromosome 20

Marker chromosomes present a problem in genetic counseling because there are often no clear phenotype-karyotype correlations. We present the clinical findings in a patient who is mosaic for a supernumerary marker chromosome 20 determined by fluorescence in situ hybridization (FISH) and compare these findings to others reported in the literature.

Diminished levels of T cell receptor zeta chains in peripheral blood T lymphocytes from patients with systemic lupus erythematosus

OBJECTIVE

To examine the expression of molecules known to participate in early T cell receptor (TCR)/CD3 signaling in peripheral blood (PB) T lymphocytes from patients with systemic lupus erythematosus (SLE).

METHODS

Signaling molecules were analyzed by immunoprecipitation and Western blotting of unstimulated PB T lymphocyte cell lysates from SLE patients, non-SLE disease controls, and healthy controls. Flow cytometry was used for analysis of the expression of membrane markers in intact cells.

RESULTS

PB T lymphocytes from SLE patients showed diminished levels of TCRzeta chains. This was not due to trapping of these molecules in the cytoskeleton, nor was it dependent on the presence of monocyte/macrophages. There was normal expression of CD3epsilon chains and normal assembly of TCR/CD3 complexes in membranes. We observed a lack of expression of TCRzeta chains in in vitro cultures of SLE T cells, and reversal of the defective expression in some patients by culturing T cells in the presence of NH4Cl.

CONCLUSION

Blood lymphocytes from SLE patients have a diminished expression of TCRzeta chains that may be related to enhanced degradation in the lysosomal compartment. The defective expression of these molecules may alter signal transduction via the CD3 pathway and contribute to abnormal T cell responses in T lymphocytes from SLE patients.

Incidence of irregular cycles among Mayan women who reported having regular cycles: implications for fertility awareness methods

Despite the low contraceptive prevalence among the Mayan population of Guatemala, past research has found interest in natural methods. A calendar rhythm method with a simple blanket rule would appear to be preferable to more complicated methods. Under a blanket rule, the number of days of abstinence is predetermined and all couples are instructed to abstain during the same interval of the menstrual cycle. However, regular menstrual cycles may be key to successful practice of a calendar method. A database of 880 cycles of 301 women of the Guatemalan highlands was analyzed to determine the length and regularity of menstrual cycles in this population.

[Neurofibroma with mucus-producing glands. Report of a case and literature review]

INTRODUCTION

Most tumors of peripheral nerve sheaths containing glands are malignant tumors associated with Von Recklinghausen's disease.

CLINICAL CASE

A 39 year old man consulted with a tumour on a finger of the right hand, which was not painful, and was slow growing. There was no past history of neurofibromatosis. Histological study showed a tumour of the peripheral nerve sheath, a benign type of neurofibroma containing glands. Immunohistochemical techniques confirmed that it had the stroma of a Schwannoma with well-defined glandular epithelial elements.

CONCLUSIONS

A neurofibroma with glands is considered to be a rare type of divergent differentiation, and of considerable interest to pathologists, since it must be differentiated from other tumoral lesions. Immunohistochemical study is very useful for this.

Protein tyrosine kinase activity in T lymphocytes from patients with systemic lupus erythematosus

We have recently observed an abnormal pattern of protein tyrosine phosphoryl-ation in resting T lymphocytes obtained from peripheral blood of patients with systemic lupus erythematosus (SLE). To examine whether these findings may be related to dysregulated protein tyrosine kinase (PTK) function, we tested the relative amount and enzyme activity of the main PTKs involved in the earliest signalling steps triggered via the CD3 pathway. Cell lysates from peripheral blood T cells in SLE patients showed lower amounts of p59(fyn) and p56(lck) as shown by immunoblot. In contrast, the amount of ZAP-70, a PTK of the syk family, was comparable in both groups. However, p59(fyn) immuno-precipitates obtained from unstimulated peripheral blood SLE T cells showed enhanced PTK activity as compared to controls, whereas the PTK activity of p56(lck) and ZAP-70 molecules was comparable in both groups. The unchecked activity of the TCR/CD3-associated src kinase p59(fyn) may alter the balance needed for regulated T cell responses in SLE patients.

[Central neurocytoma]

INTRODUCTION

A central neurocytoma (CN) is a rare tumor, of neuronal origin, well-differentiated and found intraventricularly. It mainly affects young adults. Firm diagnosis is made on immunohistochemical (IHQ) and ultrastructural studies, since on optic microscopy it is similar in appearance to an oligodendroglioma or to an ependymoma.

PATIENTS AND METHODS

We studied 4 cases, three after surgical resection and one on autopsy. The average age was 29, ranging from 3 to 63. Both sexes were equally affected. In all cases IHQ techniques were used (GFAP, neurofilament, synaptophysin and specific neuronal enolase) and they were studied by electron microscopy.

RESULTS

IHQ was negative for GFAP and neurofilament, but intensely positive for synaptophysin and specific neuronal enolase. On ultrastructural study there were few neurofilaments, microtubules and dense central granules typical of neural differentiation.

CONCLUSIONS

The findings in our cases lead to diagnosis of NC and confirm that this tumor is a distinct clinicopathological entity.

Effect of Spirulina maxima consumption on reproduction and peri- and postnatal development in rats

Spirulina maxima, an edible micro-organism useful in human nutrition, was examined for its effect on general reproductive performance and for peri- and postnatal toxicity in rats at levels of 0, 10, 20 and 30% (w/w) incorporated into the diet. There was no reduction in body weight gain in males or females and no deaths or clinical signs of toxicity. Treatment was not associated with any adverse effect on any measure of reproductive performance, including male and female fertility and duration of gestation. There was no increase in the number of abnormal pups at caesarean section or at birth. S. maxima consumption did not result in adverse effects on developmental markers of the pups.

Antifertility effects of (+)-S-2-amino-6-iodoacetamidohexanoic acid (2-AIHA) in female rats

(+)-S-2-amino-6-iodoacetamidohexanoic acid (AIHA), an irreversible inhibitor of the ornithindecarboxylase and extrahepatic arginase enzymatic activities with antineoplasic properties, was evaluated for antifertility activity in pregnant rats by oral administration at different periods of gestation. Our results showed that doses of 10 and 20 mg/kg of AIHA orally administered produced a contraceptive effect when it was administered from days 2 to 5, and 8 to 12 of gestation, respectively. The gestation time was slightly shortened when AIHA was applied from day 15 until labor. No sign of external malformations in fetuses was observed. On the other hand, AIHA did not affect the total length of oestrous cycle at the same dosage level used to interrupt pregnancy. In ovariectomized immature rats, neither changes in uterine weight, premature vaginal opening, or cornified cells were found. However, AIHA enhanced the estradiol-induced increase in uterine weights when both were concomitantly administered.

[Evaluation of the toxicity of indorenate on reproduction]

Indorenate (TR3369) a new antihypertensive drug, was examined for effects upon general reproductive performance, for peri-postnatal and embryofetal toxicity in the rat at doses of 0, 10, 20, 40 and 60 mg/kg/day by oral administration. Excluding the 60 mg/kg dose, in the fertility study, any dose produced neither decrement of body weight gain of progenitors, fertility, fetal weight nor survival rate. Retardation of the surface righting, pinnal unfolding or startle response were not observed. On the other hand, 40 and 60 mg/kg significantly increased the number of resorptions. In the peri-postnatal study, doses of 40 and 60 mg/kg incremented the number of dead pups at birth, and the later also affected the survival rate, growing and air righting reflex. Reproductive performance of the F1 offsprings was unimpaired. Indorenate in contrast to serotonin, from which it is a structural derivative, gave no evidence of teratogenicity when administered during the period of organogenesis. It was concluded that the parameters of fetal development were not affected by doses of up to 20 mg/kg, which represents approximately 1200 times the proposed dose for hypertensive patients.

[Intestinal geohelminthosis in man and domestic animals in the riverside sections of the Valdivia River Basin, Chile]

In March-October 1987 were analyzed 1295 coprological specimens in a sample of the human population who lives in riverside localities in the Valdivia River Basin, Chile. A 23.6% of examined persons presented infection by one or more helminth species. The prevalence of infection by Ascaris lumbricoides, Trichuris trichiura and Trichostrongylidae gen. sp. were 15.5, 12.7 and 0.2%, respectively. The prevalence of human ascariosis and trichuriosis were greater in pre-school and school children. The sex of the host and prevalence of geohelminthosis did not show any relationship. Prevalences of ascariosis and trichuriosis were higher in persons from houses with no sanitary fecal and water disposal. Over 35% and 20.7% of family groups showed infection by A. lumbricoides and T. trichiura, respectively in over 40% of the members of each group. Fecal samples from domestic mammals revealed the following prevalences rates for helminth infections: in dogs 19.0 and 15.2% for Toxocara canis and Uncinaria stenocephala respectively, in cats 65.1% for Toxocara cati, and in pigs 25.4 and 3.2% for Ascaris suum and Trichuris suis respectively. Some of these species are clearly demonstrated agents of zoonoses.

[Pediatric colonoscopic polypectomy]

Colorectal polyps are relatively frequent in infancy and constitute one of the main causes of bleeding per rectum. Endoscopic polypectomy, with its lower morbidity and mortality, has revolutionized its treatment. Between October 1, 1985 and May 31, 1994, 122 polypectomies were done in 88 pediatric patients. Forty five patients (51.1%) were male and 43 female (48.9%). Forty four patients (50%) were between 1 and 5 years of age. Ninety five polyps (77.9%) were found more frequently in the rectum. Regarding the size, 63 polyps (51.6%) measured between 1 and 2 cm. Seventy three patients (83%) had a single polyp, 10 patients (11.4%) had 2 polyps and 1 patient had 12 polyps. Ninety six polyps (78.7%) were pedunculated, being this the more frequent form found. Histologically the most common was the juvenile polyp, found in 106 cases (87.6%). The polypectomies was carried out without using general anesthesia and is performed as an outpatient procedure. We had no experience of endoscopic complications. It is concluded that colonoscopy polypectomy is a useful, simple and safe procedure for treating colorectal polyps in children.