Optical Non-Invasive Approaches to Diagnosis of Skin Diseases

A number of noninvasive approaches have been developed over the years to provide objective evaluation of the skin both in health and in disease. The advent of computers, as well as of lasers and photonics, has made it possible to develop additional techniques that were impossible a few years ago. These approaches provide the dermatologist with sensitive tools to measure the skin's condition in terms of physiologic parameters (e.g., color, erythema and pigmentation, induration, sebaceous and stratum corneum lipids, barrier function, etc.). Yet, a typical dermatologic diagnosis relies primarily on the trained eyes of the physician and to a lesser extent on information from other senses, such as touch and smell. The trained senses of the dermatologist backed by his/her brain form a powerful set of tools for evaluating the skin. The golden rule in diagnosis remains the histologic examination of a skin biopsy, a rather invasive method. These tools have served the profession well. The advent of ever faster and cheaper computers and of sensitive, inexpensive optical instrumentation of minimal dimensions provides the professional with the possibility of making objective measures of a number of skin parameters

Factors Involved in Selection of a Career in Surgery and Orthopedics for Medical Students in Malawi

AimsThere is a critical shortage of Orthopedic Surgeons in Malawi as well as all countries in sub-Saharan Africa. To date, there is no published literature that has investigated surgical or Orthopedic career selection amongst African medical trainees. With the goal of facilitating recruitmentinto Surgery and Orthopedics in Malawi, we explored the key aspects of Malawian Medical Students’ choice of careers in surgical disciplines.MethodsAn on-line survey of all students in clinical years at the College of Medicine in Blantyre, Malawi was performed. The survey was anonymous and constructed de novo by a stringent process including Item Generation, Item reduction, Survey composition, Pre-testing, Assessment of Validity by a recognized survey expert, Pilot testing in on-line format byseveral Malawian Medical Students, and then formal survey testing.ResultsSurgery was the most popular specialty choice among the medical trainees (46%). General Surgery was the popular surgical specialty (27%), followed by Neurosurgery (22%) and Orthopedics (19%). The majority of students (67%) feared occupational exposure to HIV but this did not appearto be a factor in specialty choice (p=0.9). Students with Orthopedic mentors were significantly more likely to choose Orthopedics as their first choice surgical specialty (p = 0.01). Despite limited resources and surgeons in sub-Saharan Africa, surgical specialties are desirable career choices.ConclusionsThis is the first evaluation of factors involved in surgical or Orthopedic career selection in any African context. Future initiatives to improve exposure and mentorship in Orthopedics are fundamental to recruitment into the specialty

Regulated expression of human A γ-, β-, and hybrid γ β-globin genes in transgenic mice: manipulation of the developmental expression patterns.

We have introduced the human fetal gamma- and adult beta-globin genes into the germ line of mice. Analysis of the resulting transgenic mice shows that the human gamma-globin gene is expressed like an embryonic mouse globin gene; the human beta-globin gene is expressed (as previously shown) like an adult mouse globin gene. These results imply that the regulatory signals for tissue- and developmental stage-specific expression of the globin genes have been conserved between man and mouse but that the timing of the signals has changed. Because the two genes are expressed differently, we introduced a hybrid gamma beta-globin gene construct. The combination of the regulatory sequences resulted in the expression of the hybrid gene at all stages in all the murine erythroid tissues

The c-kit Ligand, Stem Cell Factor, Can Enhance Innate Immunity Through Effects on Mast Cells

Mast cells are thought to contribute significantly to the pathology and mortality associated with anaphylaxis and other allergic disorders. However, studies using genetically mast cell–deficient WBB6F1-KitW/KitW-v and congenic wild-type (WBB6F1-+/+) mice indicate that mast cells can also promote health, by participating in natural immune responses to bacterial infection. We previously reported that repetitive administration of the c-kit ligand, stem cell factor (SCF), can increase mast cell numbers in normal mice in vivo. In vitro studies have indicated that SCF can also modulate mast cell effector function. We now report that treatment with SCF can significantly improve the survival of normal C57BL/6 mice in a model of acute bacterial peritonitis, cecal ligation and puncture (CLP). Experiments in mast cell–reconstituted WBB6F1-KitW/KitW-v mice indicate that this effect of SCF treatment reflects, at least in part, the actions of SCF on mast cells. Repetitive administration of SCF also can enhance survival in mice that genetically lack tumor necrosis factor (TNF)-α, demonstrating that the ability of SCF treatment to improve survival after CLP does not solely reflect effects of SCF on mast cell– dependent (or –independent) production of TNF-α. These findings identify c-kit and mast cells as potential therapeutic targets for enhancing innate immune responses

G band atmospheric radars: new frontiers in cloud physics

Clouds and associated precipitation are the largest source of uncertainty in current weather and future climate simulations. Observations of the microphysical, dynamical and radiative processes that act at cloud scales are needed to improve our understanding of clouds. The rapid expansion of ground-based super-sites and the availability of continuous profiling and scanning multi-frequency radar observations at 35 and 94 GHz have significantly improved our ability to probe the internal structure of clouds in high temporal-spatial resolution, and to retrieve quantitative cloud and precipitation properties. However, there are still gaps in our ability to probe clouds due to large uncertainties in the retrievals. The present work discusses the potential of G band (frequency between 110 and 300 GHz) Doppler radars in combination with lower frequencies to further improve the retrievals of microphysical properties. Our results show that, thanks to a larger dynamic range in dual-wavelength reflectivity, dual-wavelength attenuation and dual-wavelength Doppler velocity (with respect to a Rayleigh reference), the inclusion of frequencies in the G band can significantly improve current profiling capabilities in three key areas: boundary layer clouds, cirrus and mid-level ice clouds, and precipitating snow

G band atmospheric radars: New frontiers in cloud physics

Clouds and associated precipitation are the largest source of uncertainty in current weather and future climate simulations. Observations of the microphysical, dynamical and radiative processes that act at cloud scales are needed to improve our understanding of clouds. The rapid expansion of ground-based super-sites and the availability of continuous profiling and scanning multi-frequency radar observations at 35 and 94 GHz have significantly improved our ability to probe the internal structure of clouds in high temporal-spatial resolution, and to retrieve quantitative cloud and precipitation properties. However, there are still gaps in our ability to probe clouds due to large uncertainties in the retrievals. The present work discusses the potential of G band (frequency between 110 and 300 GHz) Doppler radars in combination with lower frequencies to further improve the retrievals of microphysical properties. Our results show that, thanks to a larger dynamic range in dual-wavelength reflectivity, dual-wavelength attenuation and dual-wavelength Doppler velocity (with respect to a Rayleigh reference), the inclusion of frequencies in the G band can significantly improve current profiling capabilities in three key areas: boundary layer clouds, cirrus and mid-level ice clouds, and precipitating snow. © 2014 Author(s)