Breast cancer classification according to immunohistochemistry markers: subtypes and association with clinicopathologic variables in a peruvian hospital database.

Background: Molecular classification is an excellent prognostic and predictive method in breast cancer (BC). In this study. we evaluated differences in clinicopathologic features and overall survival (OS) in four BC molecular subtypes: luminal A, luminal B, basal cell-like, and HER2/neu.

Destabilization of the A1 domain in von Willebrand factor dissociates the A1A2A3 tri-domain and provokes spontaneous binding to glycoprotein Ibalpha and platelet activation under shear stress.

This study used recombinant A1A2A3 tri-domain proteins to demonstrate that A domain association in von Willebrand factor (VWF) regulates the binding to platelet glycoprotein Ibalpha (GPIbalpha). We performed comparative studies between wild type (WT) A1 domain and the R1450E variant that dissociates the tri-domain complex by destabilizing the A1 domain. Using urea denaturation and differential scanning calorimetry, we demonstrated the destabilization of the A1 domain structure concomitantly results in a reduced interaction among the three A domains.

The complexities of porin genetic regulation.

Our understanding of porin regulation has revealed not only increasing complexity in the regulatory mechanisms, but also that the porin repertoire is more extensive than previously conceived. Initially, the OmpR response regulator was described as the master regulator of porin genes, but many more regulators are involved such as CpxR, PhoB, Lrp, Rob, MarA, SoxS, CadC, CRP, Fnr, ToxR, H-NS, StpA, IHF, HU and LeuO. In addition to MicF, the first small RNA (sRNA) that was proposed to regulate porin expression, porins are post-transcriptionally regulated by a variety of other sRNAs, namely, MicC, MicA, IpeX, RseX, InvR, CyaR and RybB.

The catalytic subunit of protein phosphatase 1 gamma regulates thrombin-induced murine platelet alpha(IIb)beta(3) function.

Background: Hemostasis and thrombosis are regulated by agonist-induced activation of platelet integrin alpha(IIb)beta(3). Integrin activation, in turn is mediated by cellular signaling via protein kinases and protein phosphatases. Although the catalytic subunit of protein phosphatase 1 (PP1c) interacts with alpha(IIb)beta(3), the role of PP1c in platelet reactivity is unclear.

Extracellular tumor-related mRNA in plasma of lymphoma patients and survival implications.

Background: We studied anomalous extracellular mRNAs in plasma from patients with diffuse large B-cell lymphoma (DLBCL) and their survival implications. mRNAs studied have been reported in the literature as markers of poor (BCL2, CCND2, MYC) and favorable outcome (LMO2, BCL6, FN1) in tumors. These markers were also analyzed in lymphoma tissues to test possible associations with their presence in plasma.

Predictors of school dropout among adolescents in Puerto Rico.

Objective: This research aims to understand the circumstances associated with school dropout in a cohort of Puerto Rican adolescents.

Methods: The study collected data from adolescents and their parents. Information related to school dropout among adolescents was obtained from the second year follow-up data from the longitudinal study funded by NIDA "Risky Families Embedded in Risky Environments" (Grant No.

Force-induced cleavage of single VWFA1A2A3 tridomains by ADAMTS-13.

A disintegrin and metalloprotease with a thrombospondin type 1 motifs 13 (ADAMTS-13) regulates hemostasis by cleaving the folded A2 domain of von Willebrand factor (VWF). The cleavage is regulated by forces as it occurs in flowing blood. We tested the hypothesis that force-induced A2 domain unfolding facilitates cleavage using atomic force microscopy to pull single VWF A1A2A3 tridomain polypeptides by platelet glycoprotein Ibalpha or antibodies to measure time, distance, and force.

Changes in thermodynamic stability of von Willebrand factor differentially affect the force-dependent binding to platelet GPIbalpha.

In circulation, plasma glycoprotein von Willebrand Factor plays an important role in hemostasis and in pathological thrombosis under hydrodynamic forces. Mutations in the A1 domain of von Willebrand factor cause the hereditary types 2B and 2M von Willebrand disease that either enhance (2B) or inhibit (2M) the interaction of von Willebrand factor with the platelet receptor glycoprotein Ibalpha. To understand how type 2B and 2M mutations cause clinically opposite phenotypes, we use a combination of protein unfolding thermodynamics and atomic force microscopy to assess the effects of two type 2B mutations (R1306Q and I1309V) and a type 2M mutation (G1324S) on the conformational stability of the A1 domain and the single bond dissociation kinetics of the A1-GPIbalpha interaction.

Haemoglobin blocks von Willebrand factor proteolysis by ADAMTS-13: a mechanism associated with sickle cell disease.

Vascular occlusion, thromboembolism and strokes are hallmark events in sickle cell disease (SCD). The von Willebrand factor (VWF), largest adhesive protein in circulation, has been implicated as major component in these processes. In SCD, a high level of extracellular haemoglobin (Hb) in plasma has been shown parallely associated with the disease pathogenesis.

The DNA static curvature has a role in the regulation of the ompS1 porin gene in Salmonella enterica serovar Typhi.

The DNA static curvature has been described to play a key role as a regulatory element in the transcription process of several bacterial genes. Here, the role of DNA curvature in the expression of the ompS1 porin gene in Salmonella enterica serovar Typhi is described. The web server mutacurve was used to predict mutations that diminished or restored the extent of DNA curvature in the 5' regulatory region of ompS1.

Periorificial dermatitis in children: an update and description of a child with striking features.

Background: Perioral dermatitis is a relatively important and often enigmatic type of eczema.

Methods: We describe a child with this disorder and review our experience and the literature.

Results: Clinical features of perioral dermatitis in our patient and in many others described elsewhere show a high prevalence of perinasal and periocular involvement alongside perioral findings.

Effect of venting and seating techniques on the cementation of complete coverage restorations.

Statement Of Problem: The incomplete seating of crowns resulting from cementation phenomena is a universal problem for clinicians. This seating error may lead to disturbances in the occlusion, proximal contacts, reduced retention and open margins. Various cementation protocols are practiced, with no established standard that maximizes crown seating and marginal fit.

Platelet glycoprotein Ibalpha forms catch bonds with human WT vWF but not with type 2B von Willebrand disease vWF.

Arterial blood flow enhances glycoprotein Ibalpha (GPIbalpha) binding to vWF, which initiates platelet adhesion to injured vessels. Mutations in the vWF A1 domain that cause type 2B von Willebrand disease (vWD) reduce the flow requirement for adhesion. Here we show that increasing force on GPIbalpha/vWF bonds first prolonged ("catch") and then shortened ("slip") bond lifetimes.

The first 24 hours of the World Trade Center attacks of 2001--the Centers for Disease Control and Prevention emergency phase response.

On 11 September 2001, terrorists hijacked two passenger planes and crashed them into the two towers of the World Trade Center (WTC) in New York City. These synchronized attacks were the largest act of terrorism ever committed on US soil. The impacts, fires, and subsequent collapse of the towers killed and injured thousands of people.

Magnesium maintains endothelial integrity, up-regulates proteolysis of ultra-large von Willebrand factor, and reduces platelet aggregation under flow conditions.

Mg (++) regulates endothelial functions and has anti-inflammatory effects. Its effects on thrombosis have been demonstrated, but the mechanism remains poorly understood. We investigated the roles of MgSO(4) in regulating the release and cleavage of the prothrombotic ultra-large (UL) von Willebrand factor (VWF) and VWF-mediated platelet adhesion and aggregation.

Tinea nigra by Hortaea werneckii, a report of 22 cases from Mexico.

Tinea nigra is a superficial mycosis caused by Hortaea werneckii. It is an infrequent asymptomatic infection that affects human palms and soles, and is mostly observed in tropical countries. We evaluate retrospectively twenty-two confirmed cases of tinea nigra from a total of eleven yr (1997-2007) and discuss the epidemiology, clinical features and treatment of this disease.

High-risk sexual and drug using behaviors among male injection drug users who have sex with men in 2 Mexico-US border cities.

Objectives: The population of Latino men who have sex with men (MSM) and who are also injection drug users (IDUs) is understudied. We explored risk behaviors of MSM/IDUs compared with other male IDUs in 2 Mexican border cities.

Study Design: In 2005, IDUs who had injected within the previous 30 days were recruited using respondent-driven sampling (RDS) in Tijuana and Ciudad Juárez.

LeuO antagonizes H-NS and StpA-dependent repression in Salmonella enterica ompS1.

The ompS1 gene encodes a quiescent porin in Salmonella enterica. We analysed the effects of H-NS and StpA, a paralogue of H-NS, on ompS1 expression. In an hns single mutant expression was derepressed but did not reach the maximum level.

Age-related changes of NADPH-diaphorase-positive neurons in the rat inferior colliculus and auditory cortex.

Nitric oxide (NO) has been implied in age-related changes of the central nervous system (CNS) and the central auditory pathway. The present study was conducted to investigate whether the number of NO-producing cells and their morphometric characteristics in the inferior colliculus (IC) and the auditory cortex (AC) are changed with the increasing age of the subjects. IC and AC sections of adult and senile Wistar rats were studied using the histochemical detection of NADPH-diaphorase activity (NADPH-d), a marker for neurons containing nitric oxide synthase (NOS).

Selective serotonin reuptake inhibitors: use in children and adolescents with major depressive disorder.

Treatment od depression in children and adolescents is a health care question of primary importance and it is presently associated to significant social concern. In recent years some studies have appeared that throw light on the question of the use of antidepressants in these sectors of the population in which they have been used. Information provided by national agencies, associations of health professional's guidelines and other publications have been reviewed.

Purified A2 domain of von Willebrand factor binds to the active conformation of von Willebrand factor and blocks the interaction with platelet glycoprotein Ibalpha.

Background: von Willebrand factor (VWF) does not interact with circulating platelets unless it is induced to expose the binding site for platelet glycoprotein (GP)Ibalpha in the A1 domain by high shear stress, immobilization, and/or a modulator. Previous studies have implied indirectly that the A2 domain may be involved in regulating A1-GPIbalpha binding.

Objective And Methods: Because the relationship between the A1 and A2 domains has not been defined, we have investigated the effect of the A2 domain on the binding activity of the A1 domain using recombinant A domain polypeptides, multimeric VWF, and monoclonal antibodies (mAb).