A Rare Case of Signet Ring Cell Colon Cancer Presenting as Adult Colorectal Intussusception.

Signet ring cell carcinoma of the rectum is rare and typically presents with advanced disease. We report a case of a 68-year-old man who presented with left lower quadrant pain and was found to have signet ring cell carcinoma with intussusception. This case is unusual because of its polypoid growth pattern and apparent early pathological stage. We discuss the differential diagnoses and prognosis.

Acadenic Research Services at the Medical Sciences Library, Faculty of Medical Sciences Library, The University of the West Indies, St. Augustine

To profile academic library services at the Medical Sciences Library, The University of the West Indies, St. Augustine Trinidad and Tobago, highlighting reseources and initiatives that support the Faculty of Medical Sciences curriculum, research, and scholarly communication. To outline the resources and services available at the Medical Sciences Library to support teaching and learning with a focus on research.

Lymphatic and other vascular malformative/overgrowth disorders are caused by somatic mutations in PIK3CA.

OBJECTIVES: To test the hypothesis that somatic phosphatidylinositol-4,5-bisphospate 3-kinase, catalytic subunit alpha (PIK3CA) mutations would be found in patients with more common disorders including isolated lymphatic malformation (LM) and Klippel-Trenaunay syndrome (KTS). STUDY DESIGN: We used next generation sequencing, droplet digital polymerase chain reaction, and single molecule molecular inversion probes to search for somatic PIK3CA mutations in affected tissue from patients seen at Boston Children's Hospital who had an isolated LM (n = 17), KTS (n = 21), fibro-adipose vascular anomaly (n = 8), or congenital lipomatous overgrowth with vascular, epidermal, and skeletal anomalies syndrome (n = 33), the disorder for which we first identified somatic PIK3CA mutations. We also screened 5 of the more common PIK3CA mutations in a second cohort of patients with LM (n = 31) from Seattle Children's Hospital. RESULTS: Most individuals from Boston Children's Hospital who had isolated LM (16/17) or LM as part of a syndrome, such as KTS (19/21), fibro-adipose vascular anomaly (5/8), and congenital lipomatous overgrowth with vascular, epidermal, and skeletal anomalies syndrome (31/33) were somatic mosaic for PIK3CA mutations, with 5 specific PIK3CA mutations accounting for ∼ 80% of cases. Seventy-four percent of patients with LM from Seattle Children's Hospital also were somatic mosaic for 1 of 5 specific PIK3CA mutations. Many affected tissue specimens from both cohorts contained fewer than 10% mutant cells. CONCLUSIONS: Somatic PIK3CA mutations are the most common cause of isolated LMs and disorders in which LM is a component feature. Five PIK3CA mutations account for most cases. The search for causal mutations requires sampling of affected tissues and techniques that are capable of detecting low-level somatic mosaicism because the abundance of mutant cells in a malformed tissue can be low.

Alpine cushion plants inhibit the loss of phylogenetic diversity in severe environments.

Biotic interactions can shape phylogenetic community structure (PCS). However, we do not know how the asymmetric effects of foundation species on communities extend to effects on PCS. We assessed PCS of alpine plant communities around the world, both within cushion plant foundation species and adjacent open ground, and compared the effects of foundation species and climate on alpha (within-microsite), beta (between open and cushion) and gamma (open and cushion combined) PCS. In the open, alpha PCS shifted from highly related to distantly related with increasing potential productivity. However, we found no relationship between gamma PCS and climate, due to divergence in phylogenetic composition between cushion and open sub-communities in severe environments, as demonstrated by increasing phylo-beta diversity. Thus, foundation species functioned as micro-refugia by facilitating less stress-tolerant lineages in severe environments, erasing a global productivity - phylogenetic diversity relationship that would go undetected without accounting for this important biotic interaction.

Lanthanum tracer and freeze-fracture studies suggest that compartmentalisation of early bone matrix may be related to initial mineralisation.

In adult bone the calcified matrix and enclosed osteocytes are separated from the extracellular space by a continuous layer of bone lining cells. It thus appears that bone matrix is compartmentalised and, as such, may constitute a 'milieu intérieur' which is different from the general extracellular space. Since adult bone matrix is compartmentalised and matrix vesicles also form a microcompartment, it is conceivable that compartmentalisation, in early osteogenesis, may be a requirement for the initial events of the mineralisation process. We have therefore conducted an ultrastructural, tracer, and freeze-fracture study to determine the stage in which bone matrix becomes compartmentalised and also to find out whether there are tight junctions between osteoblasts. The results show that in early nonmineralised stages and in incipient mineralisation, lanthanum penetrates all intercellular spaces and the newly forming bone matrix which is rich in matrix vesicles and collagen. With the progression of mineralisation, when all matrix vesicles appear mineralised and calcification is 'spreading' to the surrounding matrix, lanthanum is restricted to intercellular spaces and conspicuous macular tight junctions are present between osteoblasts. We suggest that matrix vesicles act as microcompartments for calcification when the early bone matrix is in continuity with the surrounding extracellular space. In later stages, when lanthanum fails to penetrate the matrix, matrix vesicles may no longer be necessary because the bone matrix itself is compartmentalised, thus allowing for localised changes in composition that might favour mineral deposition.

[A bio-psycho-social approach to acute hypertensive disease in pregnancy]. / Un enfoque bio-psico-social de la enfermedad hipertensiva aguda del embarazo.

In this paper, the approach to the genesis of the acute hypertension of pregnancy, uses a conceptual and methodological perspective adjusted to its multifactorial nature; a set of questions with epidemiologic focus is proposed, in order to vinculate psychosocial factors with the biologic processes characteristic of this health problem.

Gente Joven: a community program for Mexico's young people.

PIP: Mexfam, the Mexican Foundation for Family Planning, came to the conclusion that for family planning programs to succeed, the emphasis had to be shifted from adults to young people. The 1st community youth program, Gente Joven, began operations in 1985 in San Berabe, a very poor community south of Mexico City. Mexfam established the age group of 11-20 as the target group and adopted the slogan "It is not safe for you to have children before the age of 20." This message was aimed at the poor sector, about 70% of the population of Mexico. A long-term goal is for the sex education program to reach every young boy and girl between the ages of 11 and 12. It should cover the topics of 1) communication between family members, 2) whether or not to have sex before marriage, 3) the anatomy and physiology of female and male sex organs, 4) sexually transmitted diseases, and 5) contraceptive methods. Films on communication between family members, early sexual relations, male and female sex roles, and juvenile drug addiction were produced. Case studies on Mexfam's programs in Colima and Armeria are described, as are educational materials including drama and rock. A brief history of Mexfam is also include.^ieng

Tumores de la estroma endometrial. / Endometrial stromal tumors

1. Se presentan 5 casos de tumores de la estroma endometrial revisando su historia clinica, diagnostico histopatologico, tratamiento, seguimiento y pronostico.2.Estos casos son aprovechados para revisar los conceptos actuales en cuanto a su clasificacion, caracteristicas clinicas, tratamiento y factores conocidos que determinan su pronostico