Everyday Practice of Science: Where Intuition and Passion Meeting Objectivity and Logic

This book describes how scientists bring their own interests and passions to their work, illustrates the dynamics between researchers and the research community ..

Collagenase-1 Complexes with α2-Macroglobulin in the Acute and Chronic Wound Environments

The purpose of this study was to examine the appearance and activation of collagenase-1 (MMP-1) in the wound environment. We found that MMP-1 accumulates in the fluid phase of the burn wound environment within 2 d of injury and reaches maximal levels by day 4. Two forms of the enzyme were evident; one that corresponded to proMMP-1 and another that corresponded to a group of high molecular mass (≈200 kDa and >200 kDa doublet) MMP-1 containing complexes. ProMMP-1 and MMP-1 containing complexes also occurred in wound fluid from venous stasis ulcers, but neither was detected in mastectomy fluid or in plasma. Levels of the proteinase inhibitor α2-macroglobulin in burn fluid and chronic ulcer wound fluid were almost as high as in plasma, and the high molecular mass MMP-1 containing complexes in burn fluid appeared to result from binding between α2-macroglobulin and activated MMP-1. These observations provide direct evidence that active MMP-1 in the fluid phase of the wound environment becomes complexed to α2-macroglobulin

Degradation of Fibronectin and Vitronectin and Vitronectin in Chronic Wound Fluid: Analysis by Cell Blotting, Immunoblotting, and Cell Adhesion Assays

We used a combination of cell blotting, immunoblotting, and cell adhesion assays to analyze fibronectin and vitronectin in wound fluid from acute and chronic wounds. Acute wound fluid (e.g., suction blister fluid, mastectomy fluid) contained intact fibronectin and vitronectin as major cell adhesion proteins. In marked contrast, chronic wound fluid samples from three of 11 patients with venous stasis ulcers showed complete degradation of vitronectin and degradation of fibronectin into small molecular mass polypeptides less than 125 kDa. Three of these polypeptides —54, 93, and 125 kDa — were biologically active in promoting cell attachment and were recognized by monoclonal antibodies that bind fibronectin near the arg-gly-asp (RGD) domain. In wound fluid samples from the other eight of 11 patients, only slight degradation of vitronectin and fibronectin occurred, which resulted in a mixture of mostly intact molecules along with large fragments. Intact fibronectin in chronic wound fluid samples contained the ED-A domain, which showed that fibronectin synthesis occurred locally in the wound bed. Wound fluid containing extensively degraded vitronectin and fibronectin reversibly inhibited cell adhesion, and excess fetal bovine serum, but not purified fibronectin, neutralized the inhibitory effect. We suggest that protease activity in some chronic wounds may cause degradation of adhesion proteins and prevent cell adhesion necessary for normal wound closure

Introductory comments for the scientific ethics theme.

In this letter, the three Guest Editors for JMBE's first-ever themed section introduce the topic of scientific ethics and decribe the organization of essays within the special section.\u

Análisis y valoración del capital intelectual desarrollado por las maquiladoras del norte de Tamaulipas, México: el caso de Nuevo Laredo

Conocer la contribución que las Empresas extranjeras maquiladoras, ahora Industria Manufacturera, Maquiladora y de Servicios de Exportación (IMMEX) aportan a México. En la actualidad hay más de 5,000 empresas, generan 2´300,000 fuentes de trabajo directo, INEGI (2015). Aprovechando la integración económica y su situación geográfica del país continúan instalándose más. La IMMEX tiene su twin en el extranjero, por tal, un alto porcentaje de su producción se exporta. Son empresas globalizadas, favorecen así al país ingresando divisas. Para el caso de Nuevo Laredo, identificar el sector IMMEX que prodiga conocimiento, capacita y adiestramiento al personal, permitiendo así, conocer y manipular tecnología de última generación. La investigación y desarrollo propicia valor agregado, induce a innovar productos, las twins transfieren esa tecnología a su IMMEX. La competitiva y desarrollo se sustenta implantando procesos productivos y normas medio ambientales, ofreciendo seguridad dentro y fuera de la empresa, para identificase como Empresa Socialmente Responsable