Streptococcus bovis infection of the central nervous system in adults: Report of 4 cases and literature review / Infección del sistema nervioso central por Streptococcus bovis en adultos: reporte de 4 casos y revisión de la literatura

Objectives: To describe the clinical features, history and association with intestinal disease in central nervous system (CNS) S. bovis infections. Methods: Four cases of S. bovis CNS infections from our institution are presented. Additionally a systematic literature review of articles published between 1975 and 2021 in PubMed/MEDLINE was conducted. Results: 52 studies with 65 cases were found; five were excluded because of incomplete data. In total 64 cases were analyzed including our four cases: 55 with meningitis and 9 with intracranial focal infections. Both infections were frequently associated with underlying conditions (70.3%) such as immunosuppression (32.8%) or cancer (10.9%). In 23 cases a biotype was identified, with biotype II being the most frequent (69.6%) and S. pasteurianus the most common within this subgroup. Intestinal diseases were found in 60.9% of cases, most commonly neoplasms (41.0%) and Strongyloides infestation (30.8%). Overall mortality was 17.1%, with a higher rate in focal infection (44.4% vs 12.7%; p=0.001). Conclusions: CNS infections due to S. bovis are infrequent and the most common clinical form is meningitis. Compared with focal infections, meningitis had a more acute course, was less associated with endocarditis and had a lower mortality. Immunosuppression and intestinal disease were frequent in both infections.(AU)

Introducción: Streptococcus bovis, una causa bien conocida de endocarditis asociada a cáncer colorrectal, es también una causa poco frecuente de infecciones del sistema nervioso central (SNC), incluyendo meningitis, abscesos cerebrales o empiema subdural. El objetivo de este estudio es describir las características clínicas, los antecedentes médicos y la asociación con la enfermedad intestinal en las infecciones por S. bovis en el SNC. Métodos: Describimos 4 infecciones por S. bovis en el SNC en nuestra Unidad y, a continuación, presentamos una revisión bibliográfica de los artículos publicados entre 1975-2021 en PubMed/MEDLINE. Resultados: Se encontraron 52 estudios con 65 casos; 5 se excluyeron por datos incompletos. En total se analizaron 64 casos incluyendo nuestros 4: 55 con meningitis y 9 con infecciones focales intracraneales. Ambas infecciones se asociaron con frecuencia a condiciones subyacentes (70,3%) como la inmunosupresión (32,8%) o el cáncer (10,9%). En 23 casos se identificó un biotipo, siendo el más frecuente el biotipo ii (69,6%), y dentro de ellos, S. pasteurianus. En el 60,9% de los casos se detectaron enfermedades intestinales, siendo las más frecuentes las neoplasias (41,0%) y la infestación por Strongyloides (30,8%). La mortalidad global fue del 17,1%, con una tasa mayor en la infección focal (44,4 frente a 12,7%; p=0,001). Conclusiones: Las infecciones del SNC debidas a S. bovis son poco frecuentes y la forma clínica más común es la meningitis. En comparación con las infecciones focales, la meningitis tiene un curso más agudo, está menos asociada a la endocarditis y tiene una menor mortalidad. La inmunosupresión y la enfermedad intestinal fueron frecuentes en ambas infecciones.(AU)

Optimizing filters of activated carbons obtained from biomass residues for ethylene removal in agro-food industry devices.

A series of adsorbents (activated carbons, ACs) were synthesized by physical and chemical activation of olive stones (OS) and their textural and chemical characteristics determined by complementary techniques such as N2 and CO2 physisorption, pH of the point zero of charge (pHPZC), HRSEM or XPS. Samples with a wide range of physicochemical properties were obtained by fitting the activation procedure. The performance of these adsorbents in filters working under dynamic conditions was studied by determining the corresponding breakthrough curves for the ethylene removal. The physicochemical transformations of OS during activation were related with the adsorptive performance of derivative ACs. Results were compared to those obtained using commercial carbons, in particular ACs, carbon black or carbon fibers, in order to identify the properties of these materials on influencing the adsorptive performance. In general, ACs from OS perform better than the commercial samples, being also easily regenerated and properly used during consecutive adsorption cycles. CO2-activation showed to be the best synthesis option, leading to granular ACs with a suitable microporosity and surface chemistry. These results could favour the integration of this type of inexpensive materials on devices for the preservation of climacteric fruits, in a clear example of circular economy by reusing the agricultural residues.

Streptococcus bovis infection of the central nervous system in adults: Report of 4 cases and literature review.

OBJECTIVES: To describe the clinical features, history and association with intestinal disease in central nervous system (CNS) S. bovis infections. METHODS: Four cases of S. bovis CNS infections from our institution are presented. Additionally a systematic literature review of articles published between 1975 and 2021 in PubMed/MEDLINE was conducted. RESULTS: 52 studies with 65 cases were found; five were excluded because of incomplete data. In total 64 cases were analyzed including our four cases: 55 with meningitis and 9 with intracranial focal infections. Both infections were frequently associated with underlying conditions (70.3%) such as immunosuppression (32.8%) or cancer (10.9%). In 23 cases a biotype was identified, with biotype II being the most frequent (69.6%) and S. pasteurianus the most common within this subgroup. Intestinal diseases were found in 60.9% of cases, most commonly neoplasms (41.0%) and Strongyloides infestation (30.8%). Overall mortality was 17.1%, with a higher rate in focal infection (44.4% vs 12.7%; p=0.001). CONCLUSIONS: CNS infections due to S. bovis are infrequent and the most common clinical form is meningitis. Compared with focal infections, meningitis had a more acute course, was less associated with endocarditis and had a lower mortality. Immunosuppression and intestinal disease were frequent in both infections.

Silencing of ROT2, the Encoding Gene of the Endoplasmic Reticulum Glucosidase II, Affects the Cell Wall and the Sporothrix schenckii-Host Interaction.

Sporothrix schenckii is a member of the Sporothrix pathogenic clade and one of the most common etiological agents of sporotrichosis, a subcutaneous fungal infection that affects both animal and human beings. Like other fungal pathogens, the Sporothrix cell wall is composed of structural polysaccharides and glycoproteins that are covalently modified with both N-linked and O-linked glycans. Thus far, little is known about the N-linked glycosylation pathway in this organism or its contribution to cell wall composition and interaction with the host. Here, we silenced ROT2, which encodes the catalytic subunit of the endoplasmic reticulum α-glucosidase II, a processing enzyme key for the N-linked glycan core processing. Silencing of ROT2 led to the accumulation of the Glc2Man9GlcNAC2 glycan core at the cell wall and a reduction in the total content of N-linked glycans found in the wall. However, the highly silenced mutants showed a compensatory mechanism with increased content of cell wall O-linked glycans. The phenotype of mutants with intermediate levels of ROT2 silencing was more informative, as they showed changes in the cell wall composition and exposure of ß-1.3-glucans and chitin at the cell surface. Furthermore, the ability to stimulate cytokine production by human mononuclear cells was affected, along with the phagocytosis by human monocyte-derived macrophages, in a mannose receptor-, complement receptor 3-, and TLR4-dependent stimulation. In an insect model of experimental sporotrichosis, these mutant cells showed virulence attenuation. In conclusion, S. schenckii ROT2 is required for proper N-linked glycosylation, cell wall organization and composition, and interaction with the host.

Vulnerability of SARS-CoV-2 and PR8 H1N1 virus to cold atmospheric plasma activated media.

Cold Atmospheric Plasma (CAP) and Plasma Activated Media (PAM) are effective against bacteria, fungi, cancer cells, and viruses because they can deliver Reactive Oxygen and Nitrogen Species (RONS) on a living tissue with negligible damage on health cells. The antiviral activity of CAP against SARS-CoV-2 is being investigated, however, the same but of PAM has not been explored despite its potential. In the present study, the capability of Plasma Activated Media (PAM) to inactivate SARS-CoV-2 and PR8 H1N1 influenza virus with negligible damage on healthy cells is demonstrated. PAM acted by both virus detaching and diminished replication. Furthermore, the treatment of A549 lung cells at different times with buffered PAM did not induce interleukin 8 expression, showing that PAM did not induce inflammation. These results open a new research field by using PAM to the development novel treatments for COVID-19, influenza, and other respiratory diseases.

Standards of practice for hospital libraries and librarians, 2022: Medical Library Association Hospital Libraries Caucus Standards Task Force.

The Hospital Library Caucus of the Medical Library Association (MLA) follows the practice established in 1953 of developing quality indicators and best practices in the newly developing and fast-changing world of hospital libraries. As these libraries increased in number and prominence, the Joint Commission on the Accreditation of Hospitals (JCAHO) included in 1978 a hospital library standard developed in collaboration with MLA. Subsequent changes in JCAHO, then The Joint Commission (TJC) knowledge management criteria as well as technological changes in the curation and delivery of evidence-based resources influenced standards changes over the years. The 2022 standards mark the most recent edition, replacing the 2007 standards.

Current Models to Study the Sporothrix-Host Interaction.

Sporotrichosis is a worldwide distributed subcutaneous mycosis that affects mammals, including human beings. The infection is caused by members of the Sporothrix pathogenic clade, which includes Sporothrix schenckii, Sporothrix brasiliensis, and Sporothrix globosa. The fungus can be acquired through traumatic inoculation of conidia growing in vegetal debris or by zoonotic transmission from sick animals. Although is not considered a life-threatening disease, it is an emergent health problem that affects mostly immunocompromised patients. The sporotrichosis causative agents differ in their virulence, host range, and sensitivity to antifungal drugs; therefore, it is relevant to understand the molecular bases of their pathogenesis, interaction with immune effectors, and mechanisms to acquired resistance to antifungal compounds. Murine models are considered the gold standard to address these questions; however, some alternative hosts offer numerous advantages over mammalian models, such as invertebrates like Galleria mellonella and Tenebrio molitor, or ex vivo models, which are useful tools to approach questions beyond virulence, without the ethical or budgetary features associated with the use of animal models. In this review, we analyze the different models currently used to study the host-Sporothrix interaction.

Role of Protein Glycosylation in Interactions of Medically Relevant Fungi with the Host.

Protein glycosylation is a highly conserved post-translational modification among organisms. It plays fundamental roles in many biological processes, ranging from protein trafficking and cell adhesion to host-pathogen interactions. According to the amino acid side chain atoms to which glycans are linked, protein glycosylation can be divided into two major categories: N-glycosylation and O-glycosylation. However, there are other types of modifications such as the addition of GPI to the C-terminal end of the protein. Besides the importance of glycoproteins in biological functions, they are a major component of the fungal cell wall and plasma membrane and contribute to pathogenicity, virulence, and recognition by the host immunity. Given that this structure is absent in host mammalian cells, it stands as an attractive target for developing selective compounds for the treatment of fungal infections. This review focuses on describing the relationship between protein glycosylation and the host-immune interaction in medically relevant fungal species.

Desregulación emocional y conducta disocial en una muestra de adolescentes en conflicto con la ley / Emotional Dysregulation and Dissocial Behavior in a Sample of Adolescents in Conflict with the Law / Desregulação emocional e conduta dissocial numa mostra de adolescentes em conflito com a lei

Resumen Objetivo. Establecer el grado de relación entre la desregulación emocional y la conducta antisocial y delictiva en adolescentes que se encuentran en conflicto con la ley. Método. Diseño no experimental, enfoque cuantitativo, con alcance descriptivo-correlacional de temporalidad transversal. Participaron 62 adolescentes en conflicto con la ley. Se implementaron la ficha de caracterización MINI KID y la Escala de Desregulación Emocional (DERS-E). Resultados. El 54.8% de los adolescentes reportaron problemas de conducta. Según los hallazgos, la desatención emocional es diferente entre las personas con trastorno disocial y las que no lo presentan (t =4.853, p =0.031). La desatención emocional predice la aparición de trastorno disocial (β =0.030, p= 0.05, Exp(β)= 1.362). Conclusión. Los datos dan cuenta de la importancia de la revisión teórica de la conducta antisocial y de los factores asociados a ella, para establecer mejores modelos de intervención y de comprensión del fenómeno, principalmente la influencia de la regulación emocional en la aparición de la conducta disocial en adolescentes.

Abstract Objective. To establish the degree of relationship between emotional dysregulation and antisocial and criminal behavior in adolescents who conflict with the law. Method. Non-experimental design, quantitative approach, with descriptive scope - correlation of transversal temporality. Sixty-two adolescents in conflict with the law participated. The instruments used were the Characterization Sheet, MINI KID and Emotional Deregulation Scale (DERS-E). Results. 54.8% of adolescents reported behavioral problems. Emotional neglect is different between people with antisocial personality disorder and those who do not have it (t = 4.853, p = 0.031). Emotional neglect predicts the onset of antisocial personality disorder (A = 0.030, p = 0.05; Exp(-) = 1,362). Conclusion. The data showed the importance of the theoretical review of antisocial behavior and the factors associated with it in order to establish better models of intervention and understanding of the phenomenon, mainly the influence of emotional regulation on the onset of dissocial behaviour in adolescents.

Resumo Escopo. Estabelecer o grau de relação entre a desregulação emocional e a conduta antissocial e delitiva em adolescentes que estão em conflito com a lei. Metodologia. Desenho não experimental, enfoque quantitativo, com alcance descritivo-correlacional de temporalidade transversal. Participaram 62 adolescentes em conflito com a lei. Foi implementada a ficha de caracterização MINI KID e a escada de Desregulação Emocional (DERS-E). Resultados. O 54.8% dos adolescentes reportaram problemas de conduta. Segundo os achados, a desatenção emocional é diferente entre as pessoas com transtorno dissocial e as que não a presentam (t= 4.853, p= 0.031). A desatenção emocional prediz a aparição de transtorno dissocial (β = 0.030, p= 0.05, Exp(β) = 1.362). Conclusão. Os dados dão conta da importância da revisão teórica da conduta antissocial e dos fatores associados a ela, para estabelecer melhores modelos de intervenção e de compreensão do fenómeno, principalmente a influencia da regulação emocional na aparição da conduta dissocial em adolescentes.

Appraising the Community of Practice at a Hospital Library System Using a Critical Librarianship Lens.

The Kaiser Permanente health sciences librarians created inter-regional policies to standardize and guide the work of all librarians across regions. In response to the larger organization's emphasis on promoting diversity and equity in healthcare and the workplace, the library policies have evolved over time to include aspects of critical librarianship in the information services that the Kaiser Permanente librarians provide to their organization. The article describes how the inter-regional group of hospital librarians provide information services through a critical librarianship lens and provides examples of how other health sciences librarians can incorporate these principles to expand their services.

Genital disc growth in Drosophila.

Prior to completion, apoptosis causes the secretion of different signals, including proliferative signals. Signaling associated with death was discovered in Drosophila and mostly characterized by the induction of experimental death. Thus, less is known about physiological death. Here, we analyzed physiological death in the genital disc, a structure with bilateral symmetry, in different growth scenarios. To this end, we prevented or promoted death in regions or in genetic mosaics. We observed that physiological death in the genital disc was associated with proliferative signals and that both processes were JNK-dependent. The proliferative signals promoted growth in the genitalia primordia but not in the analia. Due to the proliferative signaling, the prevention of death that produced undead cells provoked asymmetric growth, high variability in proliferation, and size reduction. Death can occur in the absence of JNK but without signaling. JNK is fundamental for growth and death associated with signaling.

Características clínico-epidemiológicas de pacientes ancianos con Hipoacusia atendidos en el Hospital Calixto García / Clinical and epidemiological characteristics of elderly patients with hearing loss treated in Calixto García University Hospital

Introducción: El envejecimiento en Cuba constituye el principal problema demográfico y la Hipoacusia es una de las condiciones crónicas más frecuentes en los adultos mayores. Objetivo: Describir las características clínico-epidemiológicas de los pacientes de la tercera edad con Hipoacusia atendidos en el Hospital Universitario General Calixto García en el período de septiembre de 2015 hasta septiembre de 2016. Material y Método: Se realizó un estudio descriptivo, transversal en el Hospital Universitario General Calixto García durante el período de septiembre de 2015 hasta septiembre de 2016. La población (N) estuvo constituida por 387 pacientes de la tercera edad, quienes asistieron a consulta en el período estudiado. Resultados: Predominó la Hipoacusia en los pacientes con edades entre 65 y 79 años (67,2 por ciento) y el sexo masculino fue el más afectado con esta discapacidad (69,5 por ciento). La Hipoacusia en el anciano se asoció con frecuencia a otras afecciones crónicas como las enfermedades cardiovasculares. La Presbiacusia o Hipoacusia asociada a la edad fue la causa más frecuente de sordera. Conclusiones: La Hipoacusia resultó ser una discapacidad frecuente en los pacientes masculinos de la tercera edad. La misma estuvo asociada a enfermedades crónicas no trasmisibles. Las perdidas auditivas neurosensoriales y mixtas, de moderada y severa intensidad, fueron las más frecuentemente encontradas en la audiometría tonal(AU)

Introduction: Aging constitutes the main demographic problem in Cuba, and hearing loss is one of the most frequent chronic conditions in older adults. Objective: To describe the clinical and epidemiological characteristics of elderly patients with hearing loss, treated in Calixto Gracía University Hospital during the period from September 2015 to September 2016. Material and Method: A descriptive cross-sectional study was conducted in Calixto Garcia University Hospital during the period from September 2015 to September 2016. The population (N) was composed of 387 elderly patients, who went to the doctor´s office during the period under study. Results: Hearing loss predominated in patients aged from 65 to 79 years (67,2 percent), and the male sex was the most affected by this disability (69,5 percent). Hearing loss in the elderly was frequently associated with other chronic conditions such as cardiovascular diseases. Age-related hearing loss (Presbycusis) or hearing loss associated with age was the most frequent cause of deafness. Conclusions: Hearing loss was a frequent disability in male elderly patients. It was associated with non-communicable chronic diseases. Sensorineural and mixed hearing losses of moderate and severe intensity were the most frequent ones found in the tonal audiometry(AU)

Distribution of beach litter along the coastline of Cádiz, Spain.

A total of 59 categories of litter items were found at 20 beaches (13 mechanically cleaned, 7 non-cleaned) in the Cádiz tourist environment, Spain. Cluster Analysis and Principal Components Analysis were used to highlight similarities and contrasts between sites and/or associations between litter categories. Multivariate analyses separated beaches according to the total numbers of litter items present. Non-cleaned sites showed a variety of litter category abundance with distinct origins and abundant, ubiquitous items (plastic and glass fragments). Of the 7 non-cleaned beaches (49 litter categories) river-mouth sites were distinct due with high numbers of litter items. The sheltered inner part of Cádiz Bay beaches had a wide range of litter type. Many sites were associated with locally deposited recreational litter categories; while industrial/commercial/fishing categories were abundant only at a few sites, indicating items transported onto the shore from the Guadalete river.

Streptococcus bovis septic arthritis and osteomyelitis: A report of 21 cases and a literature review.

BACKGROUND: The Streptococcus bovis group (SBG) is a well-known cause of endocarditis, but its role in osteoarticular infections (OAIs) has not been well described. METHODS: We analyzed all patients with OAIs by SBG diagnosed in our hospital (1988-2014). We selected those cases with septic arthritis and osteomyelitis, as defined according to clinical, microbiological, and imaging studies. Identification of the strains was performed by using the API 20 Strep and the GP card of the Vitek 2 system, and confirmed the identification by molecular methods. In addition, we reviewed the literature to select all cases of OAI by SBG during the period 1980-2015. RESULTS: From the 83 cases of OAI included in the analysis (21 from our center and 62 from the literature review), 59 were osteomyelitis (57 of them spondylodiscitis) and 24 were arthritis (2 with associated spondylodiscitis). The mean age was 66.9 years, and 79.2% of the patients were men. Endocarditis (IE) was associated with 59% of the cases and this association was greater for osteomyelitis than for arthritis (78.9% vs. 13.6%; P = 0.001). OAI was a presenting symptom in 63% of the cases of IE. Colonoscopy was performed in 64 cases, which detected colorectal neoplasm (CRN) in 46 patients (71.8%), almost all asymptomatic. Some 69.5% of these neoplasm were carcinomas or advanced adenomas. The blood cultures were positive in 78.3% cases. In 45 cases, the S. bovis species was identified; in 82.2% of the cases the cause was Streptococcus gallolyticus subsp. gallolyticus. The mortality was 7.2%, which in no case was attributable to the OAI. CONCLUSIONS: OAIs are frequently the initial manifestation of IE caused by SBG. S. gallolyticus causes most of these infections. Echocardiogram and colonoscopy are therefore mandatory, given the species' close association with IE and CRN.

Dpp-expressing and non-expressing cells: two different populations of growing cells in Drosophila.

There are different models that explain growth during development. One model is based on insect and amphibian regeneration studies. This model proposes that growth is directed by pattern, and growth takes place by intercalation at a growth discontinuity; therefore, proliferation should surround the discontinuity. Currently, this model, apart from regenerative studies on mostly adult patterning, has not found supporting evidence in Drosophila that shows proliferation surrounding a discontinuity. Despite this lack of evidence, the importance of discontinuities has been shown in different experiments, even under wt conditions, more specifically in the formation of the leg joints because of the occurrence of cell death at their boundaries. Here, we show the existence of a sharp discontinuity in Decapentaplegic (Dpp) in the genital discs at the third larvae stage (L3), which determines the upregulation in the Jun-NH2-Terminal-Kinase (JNK) pathway, reaper (rpr), head involution defective (hid) and active caspases from its boundaries. The proliferation and cell death surrounding the discontinuity suggest that growth can proceed by intercalation and competitive death takes place in this area. Finally, we show that the Rpr, Grim and Hid (RGH) products are a few of the factors that define the growth discontinuity because they are negative regulators of growth, a new function that is unique from their known functions in apoptosis.

Both JNK and apoptosis pathways regulate growth and terminalia rotation during Drosophila genital disc development.

Apoptosis is necessary for the regulation of growth during development, but the precise details of this regulation have not been completely characterized. In this study, we used the Drosophila genital disc as a model to analyze the contribution of apoptosis to growth regulation. We studied the expression or activity of several elements of the apoptotic death pathway such as Drosophila inhibitor of apoptosis1, caspases, the apoptotic genes reaper (rpr) and head involution defective, as well as elements of the Jun-NH2-terminal kinase (JNK) pathway. We found that the JNK pathway is active in a dynamic, asymmetric and genitalia-specific manner. Apoptosis, as measured in terms of the expression of a variety of apoptotic molecules, occurs in a JNK-dependent and -independent manner and was detected among engrailed (en) expressing cells. JNK regulation of apoptotic genes is necessary to control growth in both sexes and rotation in males; this regulatory role is necessary to execute en(+) cell death and to activate expression of rpr in these cells. rpr is up-regulated at antero-posterior borders, and this expression appears to be of particular importance in the control of growth, since the balance between cell proliferation and death in those regions appears to depend on the equilibrium between pro- and anti-apoptotic factors at a cellular level.

PVF1/PVR signaling and apoptosis promotes the rotation and dorsal closure of the Drosophila male terminalia.

The Drosophila adult male terminalia originate from the genital disc. During the pupal stages, the external parts of terminalia evert from two ventral stalks; the everted left and right dorsal halves fuse at the dorsal midline. At the same time the male terminalia perform a 360 clockwise rotation. Several mutations are known to affect the rotation of the male terminalia, while none is known to affect dorsal closure. We show here that the Pvf1 gene, encoding one of the three Drosophila homologues of the mammalian VEGF/PDGF growth factors, is required for both processes. Males either mutant for Pvf1 or bearing a dominant negative form of Pvr or stasis (stai), the unique PVF receptor, do not complete either rotation or dorsal closure. Pvf1 expression in the genital disc is restricted to the A8 cells. However, PVF1/PVR signaling influences A8, A9 and A10 cells, suggesting that the PVF1 protein diffuses from its source. Flies hemizygous for the apoptotic genes hid, reaper and grim, or mutant for puckered which encodes a phosphatase that down-regulates the n-Jun-N terminal kinase pathway, lead to the same phenotypes as mutations in PVF1/PVR. Our results indicate that PVF1/PVR signaling functions not only in apoptotic phenomena but are also required during rotation and dorsal closure of the Drosophila male genital disc.

Correlación clinicopatológica perinatal en el Hospital de San José de Bogotá

Teniendo en cuenta la disponibilidad de datos en los archivos de autopsias del servicio de patología y los datos clínicos correspondientes, decidimos realizar un estudio descriptivo longitudinal de tipo retrospectivo, utilizando esta información, obtenida a través de los diez años comprendidos entre enero de 1980 y diciembre de 1989. Se plantearon como objetivos determinar la correlación clinicopatológica de los diagnósticos perinatales; presentar la distribución de los diagnósticos anatomopatológicos y realizar un diagnóstico de la mortalidad perinatal teniendo en cuenta variables como: sexo, edad gestacional, edad postnatal, Apgar, peso y días de hospitalización. Proponemos el uso habitual de esa clasificación para todas las muertes perinatales, con el fin de facilitar estudios posteriores que contribuyan a enriquecer los conocimientos del personal médico involucrado en el manejo de estos pacientes. Los datos en los que se basa este estudio se codificaron según la clasificación de mortalidad perinatal adoptada en 1958 por el estudio de mortalidad perinatal británico (British Perinatal Mortality Survey) revisada por Hey, Lloyd y Wiggleswoth en 1986.