A systematic review and meta-analysis of dementia prevalence in seven developing countries: A STRiDE project.

The STRiDE project sets out to support the development of effective dementia policy in middle-income countries (Brazil, India, Indonesia, Jamaica, Kenya, Mexico, and South Africa). As part of this it will generate new data about the prevalence of dementia for a subset of these countries. This study aims to identify the current estimates of dementia prevalence in these countries and where the gaps lie in the current literature. A systematic review was completed on 30th April 2019 across electronic databases, identifying dementia prevalence literature originating from any of the seven countries. Four hundred and twenty-nine records were identified following de-duplication; 28 studies met the inclusion criteria and were included in the systematic review. Pooled estimates of dementia prevalence ranged from 2% to 9% based on DSM-IV criteria; these figures were generally higher in studies using other diagnostic criteria (e.g. the 10/66 algorithm). Available prevalence data varied between countries. Only Brazil, Mexico and India had data derived from studies judged as having a low risk of bias. Irrespective of country, studies often were not explicit in detailing the representativeness of their sample, or whether there was non-response bias. Further transparent and externally valid dementia prevalence research is needed across the STRiDE countries.

What do we know about parasites of wildlife in high biodiversity areas with anthropogenic disturbance? The special case of Mexico.

The continual rise of anthropogenic disturbance of ecosystems has been associated with an increasing incidence of emerging diseases. The largest amount of data on emerging diseases relates to bacterial and viral pathogens, but there is a lack of parasite data, especially from wildlife. Monitoring wildlife parasitic diseases should be considered a priority, especially in high biodiversity regions with strong anthropogenic impacts, like Mexico, where the wildlife/livestock/human interface is associated with increased risk of disease transmission. Mexico belongs to the top-ten megadiverse countries and is located between two biogeographic regions. This situation makes Mexico a favourable region for the spillover of animal pathogens to human beings, causing pandemics, such as the one recently caused by influenza virus A (H1N1). The current state of knowledge of Mexican wildlife parasites is scarce and focuses mainly in Neotropical fauna. Moreover, this knowledge is heterogeneous for different parasite groups, especially concerning their pathologic effects and epidemiology. The goals of this review are to compile information on Mexican wildlife parasites and to identify knowledge gaps in order to stimulate research on pending epidemiological, public health, ecological and pathological areas, and to encourage the creation of more specialized groups from the perspective of the One-Health concept.

Determinants associated with chronic and incident depression in Mexican older adults. / Determinantes asociados a depresión crónica e incidente en adultos mayores mexicanos.

Objective: To describe the association among socio-demographic, environmental, psychosocial and health determinants in Mexican elders with chronic and incident depression from a 3-year follow-up study. Methods: Data from a cohort study of 1512 Mexicans, 65 and more years old was analyzed. We used a multinomial regression model in order to analyze the associations between determinants of interest with chronic and incident depression conditions, taking as reference a group without depression. In addition, the risk profiles were identified and stratified by sex; and finally, the determinant´s were estimated individually and combined. Results: 43.1% of the whole sample did not present depression during the follow-up, 41.9% had chronic depression and 15% incident depression. Chronic depression had more associations with determinants, than incident depression; the latter was associated with poverty and loneliness. The risk profiles for the three depression´s conditions stratified by sex, showed notorious differences. Conclusion: Chronic and incident depressions in the elderly are distinct phenomena, the evaluation of the determinant´s contribution to these entities, will allow to identify associated conditions to chronic and incident depression, and the sex differential effect, which will contribute to identify populations and risk factors, to implement objective interventions.

Self-Assembly and Anti-Amyloid Cytotoxicity Activity of Amyloid beta Peptide Derivatives.

The self-assembly of two derivatives of KLVFF, a fragment Aß(16-20) of the amyloid beta (Aß) peptide, is investigated and recovery of viability of neuroblastoma cells exposed to Aß (1-42) is observed at sub-stoichiometric peptide concentrations. Fluorescence assays show that NH2-KLVFF-CONH2 undergoes hydrophobic collapse and amyloid formation at the same critical aggregation concentration (cac). In contrast, NH2-K(Boc)LVFF-CONH2 undergoes hydrophobic collapse at a low concentration, followed by amyloid formation at a higher cac. These findings are supported by the ß-sheet features observed by FTIR. Electrospray ionization mass spectrometry indicates that NH2-K(Boc)LVFF-CONH2 forms a significant population of oligomeric species above the cac. Cryo-TEM, used together with SAXS to determine fibril dimensions, shows that the length and degree of twisting of peptide fibrils seem to be influenced by the net peptide charge. Grazing incidence X-ray scattering from thin peptide films shows features of ß-sheet ordering for both peptides, along with evidence for lamellar ordering of NH2-KLVFF-CONH2. This work provides a comprehensive picture of the aggregation properties of these two KLVFF derivatives and shows their utility, in unaggregated form, in restoring the viability of neuroblastoma cells against Aß-induced toxicity.

Combined effects of transferrin and thyroid hormone during oligodendrogenesis In vitro.

Thyroid hormones (THs) and transferrin (Tf) are factors capable of favoring myelination due to their positive effects on oligodendroglial cell (OLG) differentiation. The first notion of a combined effect of apotransferrin (aTf) and TH emerged from experiments conducted in young hyperthyroid animals, which showed a seven-fold increase in the expression of Tf mRNA and precocious myelination when compared with control animals. The mechanism underlying this phenomenon in young hyperthyroid rats could consist of an increase in Tf synthesis, which in the CNS is almost exclusively produced by OLG. Overall, our results show that, during the initial stages of OLG differentiation, Tf synthesis triggers thyroid hormone receptor alpha 1 (TRα1) expression in the subventricular zone (SVZ) and promotes proliferating cells to become responsive to this trophic factor. Exposure to TH could then regulate Tf expression through TRα1 and promote the induction of thyroid hormone receptor beta (TRß) expression, which mediates TH effects on myelination through the activation of final OLG differentiation. This regulation of the combined effects of Tf and THs implies that both factors are fundamental actors during oligodendrogenesis. GLIA 2016;64:1879-1891.

Canine myiasis by Lucilia eximia in North America.

Myiasis is the invasion of Diptera larvae in live vertebrates tissues. It has been registered in tropical areas, but not in urban animals of North America. Moreover, there is no information about lesions description, laboratory tests, and treatment applied to canines. We report a myiasis located in the dorsum of an overweight male canine. Insect larvae were identified as Lucilia eximia, an opportunistic species that scarcely infest live vertebrates, and with no records in North America animals before. Abnormalities of complete blood count like leukocytosis by neutrophilia and serum biochemical changes like elevations in alanine aminotransferase, aspartate aminotransferase, creatine kinase, globulins and amylase were detected. Because Lucilia is characterized by lower host-specificity and infestation outbreaks occur worldwide, it is imperative to continue increasing the understanding of Lucilia myiasis, its clinical presentation, risk factors, therapy and correct entomological classification. Otherwise, more cases could occur in animals and humans.

Transferrin and thyroid hormone converge in the control of myelinogenesis.

Myelination is a concerted mechanism tightly regulated in the brain. Although several factors are known to participate during this process, the complete sequence of events is far from being fully elucidated. Separate effects of apotransferrin (aTf) and thyroid hormone (TH) are well documented on rat myelin formation. TH promotes the maturation of oligodendrocyte progenitors (OPCs) into myelinating oligodendrocytes (OLGs), while aTf is able to induce the commitment of neural stem cells (NSCs) toward the oligodendroglial linage and favors OLG maturation. We have also demonstrated that Tf mRNA exhibited a seven-fold increase in hyperthyroid animals. These observations have led us to hypothesize that both factors may interplay during oligodendrogenesis. To assess the combined effects of aTf and TH on proper myelination in the rat brain, Tf expression and oligodendroglial maturation were evaluated at postnatal days 10 (P10) and 20 (P20) in several experimental groups. At P10, an up-regulation of both Tf mRNA and protein, as well as myelination, was found in hyperthyroid animals, while a decrease in Tf mRNA levels and myelin formation was detected in the hypothyroid group. At P20, no differences were found either in Tf mRNA or protein levels between hyperthyroid and control (Ctrol) rats, although differences in OLG differentiation remained. Also at P20, hypothyroid animals showed decreased Tf mRNA and protein levels accompanied with a less mature myelinating phenotype. Moreover, TH and aTf differentially regulate the expression of KLF9 transcription factor as well as TRα and TRß at P10 and P20. Our results suggest that TH is necessary early in OLG development for aTf action, as exogenous aTf administration was unable to counteract the effect of low TH levels in the hypothyroid state in all the time points analyzed. Furthermore, the fact that hyperthyroidism induced an increase in Tf expression and aTf-dependent regulation of TRα strongly suggests that Tf could be involved in some of TH later effects on OLG maturation. Here we describe the possible relationship between TH and aTf and its implication in oligodendrogenesis.

Evidence for widespread Leishmania infantum infection among wild carnivores in L. infantum periendemic northern Spain.

Leishmania spp. infection was investigated in tissue samples of wild carnivores from the Spanish Basque Country (BC), by PCR and DNA sequencing. The region is at the northern periphery of Leishmania infantum endemic Iberian Peninsula and infection in the dog (reservoir) or other species has not been previously reported. Leishmania kinetoplast DNA was detected by real-time PCR (rtPCR) in 28% (44/156) of animals. Specifically, in 26% of Eurasian badgers (n=53), 29% of foxes (n=48), 29% of stone martens (n=21) and in 25-50% of less numerous species including genets, wild cats, pole cats, European mink and weasels. Infected animals particularly badgers, were most prevalent in the southernmost province of the BC (Araba) in areas dominated by arable land. Subsequent amplification and sequencing of a fragment of the rRNA internal transcribed spacer 2 (ITS2) from a subset of rtPCR positives samples confirmed the species as L. infantum, showing a high sequence homogeneity with ITS2 sequences of L. infantum from dogs and humans from southern Spain. In summary, this study reports for the first time L. infantum infection in wild carnivores from the BC including in stone martens, pole cats and minks in which infection has not been previously described. It supports the need to study infection in dogs and people in this region and is an example of the value of infection surveillance in wildlife to assess potential risks in the domestic environment and their role in spreading infections in non-endemic areas.

[Prenatal stimulation: results in the peripartum period]. / La estimulación prenatal: resultados relevantes en el periparto.

UNLABELLED: During pregnancy, the prolonged stress and worry felt by mothers can alter the development and function of the right brain hemisphere. For this reason, importance is given to prenatal stimulation programs for pregnant women. OBJECTIVES: To determine the perinatal results in the moment of childbirth in mothers who had participated in prenatal stimulation programs. MATERIAL: An experimental study was conducted in five health districts in the town of Cienfuegos (Cuba) with a view to identifying the perinatal results at the moment of childbirth in women that had participated in prenatal stimulation programs. METHODOLOGY: The study consisted of an intentional sampling of all of the subjects (n = 200 women who were 20-28 weeks pregnant). The variables studied were the following: duration of labor, baby's birth weight, Apgar score at birth, type of childbirth, and opinion of the subjects about the prenatal stimulation program. RESULTS: Of the population sample, 36% of the subjects gave birth in less than six hours; 67.5% had babies weighing 2,500-3,000 grams; and 96.5% had babies whose Apgar scores were between 8 and 9. Finally, 68.5% of the subjects had natural childbirths and 96% were satisfied with the prenatal stimulation program. CONCLUSIONS: The results obtained showed that these new prenatal stimulation programs were well received by the subjects in this study.

Cryptic Leishmaniosis by Leishmania infantum, a feature of canines only? A study of natural infection in wild rabbits, humans and dogs in southeastern Spain.

An epidemiological study was carried out to investigate asymptomatic Leishmania infantum infection by PCR and ELISA in wild rabbits, humans and domestic dogs in southeastern Spain. Seroprevalence was 0% (0/36) in rabbits, 2% (13/657) in humans and 7% (14/208) in dogs. The prevalence of PCR-positives was 0.6% (1/162) in rabbits tested in a wide range of tissue samples, 2% (8/392) in humans analysed in blood samples and 10% (20/193) and 67% (29/43) in dogs analysed in blood and lymphoid tissue samples, respectively. Results suggest that wild rabbits have a very low risk of becoming chronically infected with L. infantum, and provide further evidence that cryptic L. infantum infection is widespread in the domestic dog population and is also present in a comparatively smaller proportion of healthy humans. The epidemiological and clinical implications of these findings are discussed.

Partial inhibition of the proteasome enhances the activity of the myelin basic protein promoter.

We have previously shown that low concentrations of a specific proteasome inhibitor accelerate exit from the cell cycle and enhance oligodendroglial cell (OLGc) differentiation. To elucidate the mechanisms involved in this process, OLGcs of the N20.1 cell line, transfected with a reporter gene driven by the MBP promoter, were treated with proteasome inhibitors and/or inhibitors of different signaling pathways. Partial proteasome inhibition resulted in enhanced activation of the MBP promoter which involved the tyrosine kinase, PI3-Akt and PKC pathways, accompanied by an increase in the levels of p21(Cip1), p27(Kip1) and Sp1 and by a decrease in Nkx2.2. Binding of Sp1 to DNA was also increased. These results were not observed when the Sp1 binding site was mutated. We conclude that the enhanced activation of the MBP promoter induced by partial inhibition of the proteasome could be due, at least in part, to the stabilization of p27(Kip1) and Sp1.

[Pneumococcal endocarditis in children]. / Endocarditis por Streptococcus pneumoniae en un escolar sano.

Endocarditis caused by Streptococcus pneumoniae in children is an infrecuent disease, corresponding to 3-7 % of all cases reported. Pneumococcal endocarditis is a serious condition with a rapidly destructive nature and high fatality rate, demanding prompt medical and surgical treatment. We report a case an infant eleven years old who was admitted with endocarditis by S. pneumoniae, who presented with hearth failure and required surgery. A review of the literature of endocarditis caused by S. pneumoniae is presented.

Apotransferrin decreases the response of oligodendrocyte progenitors to PDGF and inhibits the progression of the cell cycle.

In the CNS, transferrin (Tf) is expressed by the oligodendroglial cells (OLGcs) and is essential for their development. We have previously shown that apotransferrin (aTf) accelerates maturation of OLGcs in vivo as well as in vitro. The mechanisms involved in this action appear to be complex and have not been completely elucidated. The aim of this study was to investigate if Tf participates in the regulation of the cell cycle of oligodendroglial progenitor cells (OPcs). Primary cultures of OPcs were treated with aTf and/or with different combinations of mitogenic factors. Cell cycle progression was studied by BrdU incorporation, flow cytometry and by the expression of cell cycle regulatory proteins. Apotransferrin decreased the number of BrdU+ cells, increasing the cell cycle time and decreasing the number of cells in S phase. The cell cycle inhibitors p27kip1, p21cip1 and p53 were increased, and in agreement with these results, the activity of the complexes involved in G1-S progression (cyclin D/CDK4, cyclin E/CDK2), was dramatically decreased. Apotransferrin also inhibited the mitogenic effects of PDGF and PDGF/IGF on OPcs, but did not affect their proliferation rate in the presence of bFGF, bFGF/PDGF or bFGF/IGF. Our results indicate that inhibition of the progression of the cell cycle of OPcs by aTf, even in the presence of PDGF, leads to an early beginning of the differentiation program, evaluated by different maturation markers (O4, GC and MBP) and by morphological criteria. The modulation by aTf of the response of OPcs to PDGF supports the idea that this glycoprotein might act as a key regulator of the OLGc lineage progression.

Differential effects of apotransferrin on two populations of oligodendroglial cells.

In the central nervous system (CNS), apotransferrin (aTf) is produced by oligodendroglial cells (OLGcs), and aTf is essential for cell survival. We previously demonstrated that a single intracranial injection of aTf in 3-day-old rats accelerates differentiation of OLGc and that aTf acts at early stages of development on certain populations of OLGcs, promoting accelerated maturation, with no effect on late markers of cell differentiation. The objective of the present study was to analyze OLGc maturation at two different stages of rat development, 4 and 10 days of age, in OLGcs isolated from the brain after intracranial injection of aTf at 3 days of age, and to explore the in vitro effect of aTf added to cultures of OLGc isolated from aTf-injected and control brains. The maturational cell stages were identified by immunocytochemistry with different OLGc markers and by analysis of their morphological complexity. The OLGcs isolated from 4- and 10-day-old animals intracranially injected with aTf were more differentiated than control cells. Treatment with aTf of the cultures of OLGcs that were isolated from 4-day-old saline-injected control animals induced their differentiation, while a similar treatment of the cultures of OLGcs that were isolated from 10-day-old animals did not induce further maturation of the cells. The results presented in the present report demonstrate that the in vivo effects of aTf on OLGc maturation can be reproduced in cultures and that the effects of aTf occur early in development during a narrow, transient "temporal window" within which OLGcs are sensitive to its action.

Oligodendroglial cell differentiation in rat brain is accelerated by the intracranial injection of apotransferrin.

In the present paper we first studied the brain distribution and the time and dose dependent effects of apotransferrin, after its intracranial injection into young rats and at different post-natal ages. Its action upon the transferrin receptor (TfR) and upon the expression of brain transferrin, as well as its effect on the proliferation and differentiation of oligodendroglial cells (OLGc) was one of the main objectives of our investigation. Total DNA and BrdU labeling, as an index of cellularity and proliferation, respectively, were the same in the control and experimental groups of rats. A significant increase in the MBP+ and CA II+ OLGc, and a decrease in the more immature (A2B5+) OLGc were found in the aTf injected rats. At 10 and 17 days of age, Tf-mRNA decreased to around 20% of the amount present in control animals. The TfR-mRNA in the animals receiving a single dose of aTf at 3 days of age showed an increase in its expression at 10 and 17 days of age, coincident with a higher immunoreactivity of the TfR itself of neurons, choroid plexus and brain capillaries in different brain areas. Although TfR+ OLGc were present up to 7 days of age in controls and in the Tf injected rats, no positive cells were observed at 17 days of age, even in the aTf injected rats. Our results give support to the hypothesis that aTf is an important factor necessary for the maturation of the OLGc, and that the effects that it produces in the OLGc-myelin unit after its intracranial injection in young rats are not due to an increase in proliferation, but to an accelerated differentiation of Tf-sensitive OLGc.

[Sudden infant death syndrome]. / Síndrome de la muerte súbita del lactante.

Sudden infant crib syndrome in nursing newborns means the syndrome which affects those babies less than one year old whose death can not be explained even after the conclusion of an in depth investigation. This article explains the causes currently provided as possible factors which cause this syndrome, risk factors supported by epidemiological data and preventive measures including the monitoring of babies deemed to be at risk. The authors also specify what this monitoring consists of and they elaborate a proposed nurses' action plan for the newborn and his/her family for those cases in which monitoring is taking place. The authors also present a proposed nurses' action plan in the event of a newborn's death due to this syndrome.

Prevalencia de anticuerpos contra el virus de la hepatitis A (VHA) en una poblacion de niños mexicanos / Prevalence of hepatitis A virus antibodies in Mexican children

Se analizaron los datos con relación a la prevalencia de anticuerpos IgG e IgM contra el virus de la hepatitis A (VHA), mediante la técnica de ELISA en 450 ninos sin antecedentes de hepatitis, con edades comprendidas entre los 3 meses y 17 años de edad, que acudieron a consulta al Instituto Nacional de Pediatría de la ciudad de México en el período comprendido de septiembre de 1992 a junio de 1993. La prevalencia de anticuerpos IgG en la población estudiada, fue del 83.6 por ciento. De los niños menores de un año el 50 por ciento mostraron anticuerpo, el 80 por ciento a los 3 años 80 por ciento, y el 96 por ciento a los 10 años de edad. Sólo 9 niños de los 450 tuvieron además anticuerpos IgM contra el virus de la hepatitis A. Se concluye que la prevalencia de HVA en la población que estudiamos es semejante a lo referido hace 13 años en México.

[Prevalence of antibodies against hepatitis A virus (HAV) in a population of Mexican children]. / Prevalencia de anticuerpos contra el virus de la hepatitis A (VHA) en una población de niños mexicanos.

We studied by ELISA test 450 healthy children looking for IgG and IgM antibodies against virus A hepatitis. 376/450 (86.3%) showed IgG antibodies. 50% of children under one year were positive. At 3 years of age 80% of children from this study were with antibodies IgG and 96% of children at 10 years of age were positive. Only 9 children showed antibodies IgM.

Erradicación del Helicobacter pylori en pacientes con dolor abdominal recidivante con un triple esquema de tratamiento / Erradication of Helicobacter pylori in patients with recurrents abdominal pain using a triple drug treatment

Antecedentes. Diversos esquemas de tratamiento se han utilizado para la eliminación de Helicobacter pylori en niños con gastritis, con diferentes resultados. Objetivo. Evaluar la eliminación de Helicobacter pylori, así como la mejoría clínica en niños con gastritis asociada, cuando se les administró en forma simultánea amoxicilina, ranitidina y subsalicilato de bismuto. Método. Se estudiaron 20 pacientes que acudieron al Servicio de Gastroenterología, del Instituto Nacional de Pediatría, durante el periodo comprendido entre enero de 1992 y junio de 1993. Se incluyeron todos los niños con dolor abdominal recurrene en quienes se identificó Helicobacter pylori en las biopsias de antrogástrico. El tratamiento consistió en la administración simultánea de amoxicilina durante 15 días y ranitidina y subsalicilato de bismuto durante un mes. Resultados. En 14 de 20 niños se logró mejoría clínica así como la eliminación de Helicobacter pylori. Conclusiones. La eliminación de Helicobacter pylori y la mejoría clínica se obtuvieron en el 70 por ciento de los niños, con buena tolerancia al trataiento.

[Eradication of Helicobacter pylori in patients with recurrent abdominal pain using a triple drug treatment]. / Erradicación del Helicobacter pylori en pacientes con dolor abdominal recidivante con un triple esquema de tratamiento.

BACKGROUND: Different antibiotics, antagonist H2 and others have been used for elimination and/or eradication of Helicobacter pylori. AIMS: Evaluate elimination of Helicobacter pylori with amoxicillin, bismuth subsalicylate and ranitidine; and the improvement of recurrent abdominal pain. METHOD: 20 children with recurrent abdominal pain associated to gastritis and histologic identification of Helicobacter pylori were studied under a period of 18 months (January 1992 to June 1993), at Instituto Nacional de Pediatría, México, D.F. All children were treated simultaneously with: Amoxicillin, 15 days, plus ranitidine and bismuth subsalicylate for one month. RESULTS: Helicobacter pylori was eliminated in 14 of 20 children studied. All these children had an important improvement of recurrent abdominal pain. CONCLUSION: Elimination of Helicobacter pylori and clinical improvement was present in 14 of 20 children studied (70%).