New directions in surgical therapy.

Surgical dermatology continues to evolve rapidly. The field is blessed with a number of bright and enthusiastic young surgeons who are willing to spend to necessary time investigating new techniques. The horizon has changed dramatically over the last 5 years and promises to change even more in the years to come.

The biologic basis of ultrasonic liposuction.

The use of ultrasound to facilitate liposuction is a new and potentially exciting area of clinical and research interest. Whether or not this will result in important changes in the practice of liposuction remains to be determined.

Infusion rates and levels of premedication in tumescent liposuction.

Background: Tumescent liposuction has proven to be an extremely safe and effective method of liposuction. However, the infusion of tumescent anesthesia can take 1 hour or more to complete.

Objective: To document the types, dosages, and routes of administration of premedication utilized by four experienced tumescent liposuction surgeons.

Localization of a putative liver tumor suppressor locus to a 950-kb region of human 11p11.2-p12 using rat liver tumor microcell hybrid cell lines.

We previously demonstrated that a locus (or loci) linked to the D11S436 marker, which is within the approximately 6-Mb cen-p12 region of human chromosome 11, suppresses the tumorigenic potential of some rat liver epithelial tumor microcell hybrid (MCH) cell lines. To more precisely map this putative liver tumor suppressor locus, we examined 25 loci from human chromosome 11 in suppressed MCH cell lines. Detailed analysis of these markers revealed a minimal area of overlap among the suppressed MCH cell lines corresponding to the chromosomal region bounded by (but not including) microsatellite markers D11S1319 and D11S1958E and containing microsatellite markers D11S436, D11S554, and D11S1344.

Evaluation of the differentiation potential of WB-F344 rat liver epithelial stem-like cells in vivo. Differentiation to hepatocytes after transplantation into dipeptidylpeptidase-IV-deficient rat liver.

After intrahepatic transplantation into livers of adult syngeneic German-strain Fischer 344 rats that are deficient for the bile canalicular enzyme dipeptidyl peptidase IV (DPP-IV), cultured WB-F344 rat liver epithelial cells (without exogenous marker genes) integrate into hepatic plates and differentiate into hepatocyte-like cells that are morphologically and functionally indistinguishable from mature hepatocytes. In this model system, the differentiated progeny of transplanted WB-F344 cells are identified among the DPP-IV-negative host hepatocytes by their expression of bile canalicular DPP-IV enzyme activity. DPP-IV-positive hepatocyte-like cells also expressed other markers of hepatocytic differentiation, including albumin, transferrin, and alpha-1-antitrypsin, suggesting that the progeny of transplanted WB-F344 cells express a complete hepatocyte differentiation program.

Age-dependent induction of hepatic tumor regression by the tissue microenvironment after transplantation of neoplastically transformed rat liver epithelial cells into the liver.

Age is the biggest risk factor associated with the development of cancer. Whereas the incidence of neoplastic disease increases dramatically in aging humans and experimental animals, the effects of aging on tumorigenesis are poorly understood. Using a rodent model, we have previously shown that the microenvironment of the hepatic parenchyma regulates hepatic tumor formation from transplanted neoplastic cells in an age-dependent manner.

Site-directed mutations near the L-subunit D-helix of the purple bacterial reaction center: a partial model for the primary donor of photosystem II.

We have engineered a photosynthetically competent mutant of the purple non-sulfur bacterium Rhodobacter capsulatus which seeks to mimic the behavior of the primary electron donor (P) of the plant photosystem II (PS II) reaction center (RC). To construct this mutant (denoted D1-ILMH), four residues in the bacterial L subunit were mutagenized, such that an 11-residue segment was made identical to the analogous segment from the D1 subunit of PS II. The electronic properties of the bacteriochlorophyll (Bchl) dimer which constitutes the primary donor are substantially altered by these modifications, to the degree that the dimer becomes functionally much more "monomeric".

Advances in chemical peeling.

Chemical peeling is traditionally discussed in terms of the depth of injury: superficial, medium, or deep. There have been a number of important advances in both superficial and medium-depth chemical peeling over the last several years. This article reviews the state of the art of these techniques and the increasing understanding of their effects on skin.

Biodiversity and Industry Ecosystem Management.

/ The term biodiversity describes the array of interacting, genetically distinct populations and species in a region, the communities they comprise, and the variety of ecosystems of which they are functioning parts. Ecosystem health, a closely related concept, is described in terms of a process identifying biological indicators, end points, and values. The decline of populations or species, an accelerating trend worldwide, can lead to simplification of ecosystem processes, thus threatening the stability and sustainability of ecosystem services directly relevant to human welfare in the chain of economic and ecological relationships.

Combining surgical methods for skin resurfacing.

Cutaneous resurfacing with lasers is still in its infancy. As with all new techniques, its proper place will be determined in the context of established procedures. Dermabrasion and chemical peeling have been used by dermatologists for cutaneous resurfacing for over a century.

Synaptic interactions of retrogradely labeled hypoglossal motoneurons with substance P-like immunoreactive nerve terminals in the cat: a dual-labeling electron microscopic study.

This study has investigated the synaptic interactions between hypoglossal motoneurons and substance P (SP)-immunoreactive terminals. Cholera toxin B conjugated to horseradish peroxidase was injected into the tip of the tongue on the right side of six ketamine-anesthetized cats. Two to five days later, the animals were killed.

A national outbreak of Salmonella enteritidis infections from ice cream. The Investigation Team.

Background: In September 1994, the Minnesota Department of Health detected an increase in the number of reports of Salmonella enteritidis infections. After a case-control study implicated a nationally distributed brand of ice cream (Schwan's) in the outbreak, the product was recalled and further epidemiologic and microbiologic investigations were conducted.

Methods: We defined an outbreak-associated case of S.

Assessment of a new device for injecting bovine collagen. The ADG needle.

Unlabelled: BACKGROUND Bovine collagen has been injected into skin through conventional needles since its introduction in 1981. Variations in technique have resulted in a wide range of clinical results. The success of a collagen treatment depends on proper technique and placement, which may take years of experience to develop.

A Gas Chromatographic Continuous Emissions Monitoring System for the Determination of VOCs and HAPs.

This article describes a new gas chromatography-based emissions monitoring system for measuring volatile organic compounds (VOCs) and hazardous air pollutants (HAPs). The system is composed of a dual-column gas chromatograph equipped with thermal conductivity detectors, in which separation is optimized for fast chromatography. The system has the necessary valving for stream selection, which allows automatic calibration of the system at predetermined times and successive measurement of individual VOCs before and after a control device.