Fat extrusion and septal reset in patients with the tear trough triad: a critical appraisal

Arcus marginalis release, fat extrusion, and septal reset were applied to 71 selected patients with a constellation of orbital deformities the authors term a "tear trough triad." Of the initial 71 patients, 59 had complete follow-up records. Evaluated by means of a proportional topographic scale, 95 percent of patients achieved significant improvement. Equally important, no incidence of middle lamella contracture occurred in the entire series. The authors conclude that the procedure is safe and effective in selected patients.     

Naturopathy: a critical appraisal

"Naturopathic medicine" is a recent manifestation of the field of naturopathy, a 19th-century health movement espousing "the healing power of nature." "Naturopathic physicians" now claim to be primary care physicians proficient in the practice of both "conventional" and "natural" medicine. Their training, however, amounts to a small fraction of that of medical doctors who practice primary care. An examination of their literature, moreover, reveals that it is replete with pseudoscientific, ineffective, unethical, and potentially dangerous practices. Despite this, naturopaths have achieved legal and political recognition, including licensure in 13 states and appointments to the US Medicare Coverage Advisory Committee. This dichotomy can be explained in part by erroneous representations of naturopathy offered by academic medical centers and popular medical Web sites.     

Taxonomy and fossils: a critical appraisal

Many compendia at the species, genus and family levels document the fossil record, but these are not standardized, nor usually critical in content, and few are available on the World Wide Web. The sampling of the available record is good for organisms with fossilizable parts, but preservational constraints on the entire morphology, life history and geographical distribution lead to difficulties in recognizing and naming species. We recommend abandoning some of the palaeontological species concepts such as chronospecies and stratospecies, and we advocate species recognition based on unique combinations of characters. The compilation of species lists is extremely time consuming, and given the inherent problems we suggest that compilation of generic lists is a more achievable goal because genera are recognized by definitive morphological characters. In calculating taxon duration, care must be taken to distinguish between mono-, para- and polyphyletic groups, the first being the only reliable unit for use in calculating diversity curves. We support the inclusion of fossils into classifications based on Recent organisms, but we recognize some of the problems this may pose for standard Linnaean classifications. Web-based taxonomy is the way forward, having the advantages of speed and currency of information dissemination, universal access with links to primary literature and increasingly sophisticated imagery. These advantages over conventional outlets will only be realized with careful Web design and a commitment to maintenance.     

Effectiveness of instruction in critical appraisal (evidence-based medicine) skills: a critical appraisal

OBJECTIVE: To examine the evidence that the teaching of critical appraisal (evidence-based medicine) skills to undergraduate medical students or residents will result in significant gains in knowledge and increased use of the literature in clinical decision-making. DATA SOURCES: Articles published from 1966 to 1995, retrieved through a MEDLINE search supplemented by manual searches; review of bibliographies maintained by individuals involved in teaching critical appraisal skills; and a previous methodological review. STUDY SELECTION: Articles were selected if the study involved some form of control group, although strict randomization was not required, and a measure of performance followed the intervention. Articles were excluded if they simply reported the process of teaching critical appraisal skills or used some form of "happiness index." DATA SYNTHESIS: There were 10 studies of the impact of teaching critical appraisal skills, 6 involving medical students and 4 involving residents. Results from 3 of the studies were nearly uninterpretable and thus were excluded; the remaining 7 were methodologically acceptable. Analysis showed that interventions implemented in undergraduate programs resulted in significant gains in knowledge, as assessed by a written test (mean gain 17.0%; standard deviation [SD] 4.0%). Conversely, studies at the residency level consistently showed a small change in knowledge (mean gain 1.3%; SD 1.7%). Two studies that examined residents'' use of the literature were unable to demonstrate any positive changes. CONCLUSIONS: Studies of the effect of teaching critical appraisal skills on gains in knowledge at the undergraduate level showed consistent improvement. By contrast, changes in knowledge at the residency level were small. Several suggestions from the educational literature are offered to increase effectiveness of critical appraisal interventions.     

Comparative biochemistry and physiology in Brazil: a critical appraisal

Brazil stood out as the country with the highest number of submissions to the editorial project dedicated to Latin America by the journal Comparative Biochemistry and Physiology. Therefore, we felt that it was important to critically discuss the state of comparative biochemistry and physiology in this country. Our study is based on data collected from the ISI Web-of-Science. We analyzed publication trends through time, availability of novel approaches and techniques, patterns of collaboration among different geographical regions, patterns of collaboration with researchers abroad, and relative efforts dedicated to the study of biochemical and physiological adaptation of native fauna representing different terrestrial Brazilian biomes. Overall, our data shows that comparative biochemistry and physiology is a lively and productive discipline, but that some biases limit the scope of the field in Brazil. Some important limitations are the very heterogeneous distribution of research nuclei throughout the country and the absence of some important approaches, such as remote sensing and the use of molecular biology techniques in a comparative or evolutionary context. We also noticed that international collaboration far surpasses interregional collaboration, and discuss the possible causes and consequences of this situation. Finally, we found that Brazilian comparative biochemistry and physiology is biome-biased, as the Amazonian fauna has received far more attention than the whole pool of fauna representing other terrestrial biomes. We discuss the possible causes of these biases, and propose some directions that may contribute to invigorate the field in the country.     

Microbial biosynthesis and applications of gentamicin: a critical appraisal

Gentamicin is an aminoglycoside antibiotic produced by various species of the genus Micromonospora and has received much attention in the recent years as a broad-spectrum antibiotic for treatment of various infections. It exists as a complex of closely related aminoglycoside structures and the clinically significant one is the gentamicin C complex. This review article focuses attention on the present status of knowledge and the main advancements achieved in the last few decades on the subject of gentamicin with regard to its production, biosynthetic pathway, mode of action, and uses. The various nutritional and environmental parameters affecting gentamicin production and the factors affecting the release of bound gentamicin are discussed. Further, strain improvement using UV and/or chemical mutagenesis can be applied to augment the efficiency of the producer strain and a number of case studies are presented. Different detection and quantitative methods for gentamicin estimation and the mode of action of gentamicin are discussed in detail. This antibiotic finds extensive use in combination chemotherapy and as a drug for different delivery agents for treatment of osteomyelitis and other recent applications in gene therapy.     

Sixty consecutive breast reconstructions with the inflatable expander: a critical appraisal

Breast reconstruction using inflatable expanders has become an established and preferred technique. Although our knowledge of the biomechanical changes occurring in expanded skin has increased greatly, little information is available regarding average aesthetic results achieved with this technique. In order to eliminate the bias of best case selection reports, this study of 60 consecutive patients undergoing skin-expansion breast reconstruction was undertaken. Results of the study demonstrated a significant frequency and diversity of complications. In particular, immediate breast reconstruction with skin expanders was identified as a high-risk procedure because of its association with skin necrosis and delayed wound healing. Although two procedures--insertion and replacement--had been anticipated, patients from both the Boston and New York groups required approximately three operations to complete the expansion process. Average aesthetic results, often characterized by problems of symmetry, ptosis, and contour, need to be recognized and improved.     

The evolution of molluscan photosymbioses: a critical appraisal

Partnerships between animals and photosynthesizing microbes have evolved repeatedly, although their history, adaptations, and ecology remain controversial and little understood. In a critical review of 17 fossil and living clades of shell‐bearing molluscs with photosymbionts (two of them newly inferred), adaptive shell modifications and ecological aspects are discussed in the broader context of photosymbioses in other phyla. Fossil candidates have characteristics that are rare or unknown in living photosymbiotic molluscs, including cementation, porous shell microstructure, and epifaunal habits on carbonate muds. Many ancient photosymbioses may have lived in planktonically more productive environments than are typical of living tropical forms. This may be related to the late appearance (Early Eocene) of the dinoflagellate Symbiodinium, which can thrive under highly oligotrophic conditions. Living photosymbiotic molluscs represent a small and atypical sample of all the photosymbiotic clades that have evolved. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 109 , 497–511.     

Studies on leukocyte beta-adrenergic receptors in depression: a critical appraisal

Alterations in beta-adrenergic receptors (BAR) of human mononuclear leukocytes (MNL) are considered to reflect changes in central noradrenergic function and have been studied in a number of diseases. This paper critically reviews the results of recent studies on MNL-BAR in depression, with particular emphasis on the biochemical and clinical methodologies used. Despite considerable differences in these methods, a number of laboratories report consistent decreases in MNL-BAR density and significantly reduced functional response in patients as compared to controls. These studies used MNL, isolated from patients who had a greater than 14 day drug washout, and BAR-densities were measured in membrane preparations, using full Scatchard analyses, and 125I-ICYP or 3H-DHA as the ligand. Functional response of MNL-BARs was assessed by the determination of isoproterenol-stimulated cyclic AMP accumulation. A comparison of methods used by these groups further indicates that additional biochemical parameters such as lymphocyte preparation and standardized experimental conditions for the binding assays are also important for obtaining consistent results. The clinical methods in rigorous study designs also include clearly stated inclusion/exclusion criteria for patients, and age-, and gender-matched patient-control populations. Whether the reduced MNL-BAR density and function is an inherited abnormality in depressed patients, or results from downregulation by elevated catecholamines is at present not known. Studies are needed to characterize further the changes in MNL-BARs in depression and to evaluate the effects of caetcholamines and hormones on this system. Based on critical assessment of the methods reviewed we propose specific biochemical and clinical guidelines, and recommend, that these be followed in future studies on MNL-BARs in this disease.     

The presence of actin in nuclei: a critical appraisal.

To assess the significance of actin associations with nuclei, we have examined Amoeba proteus nuclei for the presence of labeled actin under a variety of circumstances without (in most instances) isolating nuclei or breaking up cytoplasms prior to the extraction of proteins.We first established that: the 42,000 dalton proteins (presumed to be actin) present in cytoplasm and non-isolated nuclei are identical electrophoretically; the putative actin of amebas has the same size and almost the same isoelectric point as rat muscle actin; and the peptide “fingerprints” of putative ameba actin and rat actin are very similar after tryptic digestion. We therefore concluded that the 42,000 dalton protein of ameba is actin.We determined that: the concentrations of actin in the cytoplasm and nucleus of amebas are the same; actin is readily lost from nuclei that are released from lysed cells; shortly after a ³⁵S-labeled nucleus is transplanted into unlabeled cytoplasm, or an unlabeled nucleus is transplanted into ³⁵S-labeled cytoplasm, the concentration of ³⁵S-actin in nucleus and cytoplasm is the same; and when cells containing ³⁵S-actin are subjected to long chase periods on unlabeled food, the concentrations of ³⁵S-actin in nucleus and cytoplasm fall in parallel. These observations taken together suggest that actin is not tightly associated with nuclei. Rather, actin may associate with nuclei for the trivial reason that the nuclear envelope is no barrier to free movement of that protein between the two compartments.We conclude that the mere presence of actin in nuclei is insufficient grounds for assuming that it has any role in nuclear functions, such as, for example, chromosome condensation.     

The role of the septal reset in creating a youthful eyelid-cheek complex in facial rejuvenation

Resetting of the septum orbitale over the orbital rim, or "septal reset," is the latest step in achieving periorbital rejuvenation in composite rhytidectomy. The first significant step was the addition of orbicularis repositioning to conventional lateral vector deep plane rhytidectomy, followed by orbital fat preservation using the arcus marginalis release and fat transposition over the orbital rim. Those early procedures have been further refined to include the zygomaticus muscles with the orbicularis oculi in the composite flap, or zygorbicular cheek flap, and a septal reset. The septum orbitale reset has distinct advantages over transposition of orbital fat alone, as it creates a firmer undersurface for the lower eyelid. This maneuver will create a truly youthful lower eyelid-cheek complex, as the normal concave aging skeletonization of the periorbit is transformed to a convex contour of youth. The effectiveness of this operation can be demonstrated in most variations of human anatomy, whether congenital or iatrogenic, allowing the plastic surgeon to utilize the septal reset in virtually every patient undergoing and desiring a harmonious facial rejuvenation.     

Using marine macroalgae for carbon sequestration: a critical appraisal

There has been a good deal of interest in the potential of marine vegetation as a sink for anthropogenic C emissions (“Blue Carbon”). Marine primary producers contribute at least 50% of the world’s carbon fixation and may account for as much as 71% of all carbon storage. In this paper, we analyse the current rate of harvesting of both commercially grown and wild-grown macroalgae, as well as their capacity for photosynthetically driven CO₂ assimilation and growth. We suggest that CO₂ acquisition by marine macroalgae can represent a considerable sink for anthropogenic CO₂ emissions and that harvesting and appropriate use of macroalgal primary production could play a significant role in C sequestration and amelioration of greenhouse gas emissions.     

Unstable relations: a critical appraisal of indigeneity and environmentalism in contemporary Australia

The 1970s witnessed the emergence of a protest‐based environmental movement in Australia. We outline here the history of the unstable meeting of environmentalism and Aboriginal interests, before turning to Marcia Langton's recent critique of the progressive ‘green left’ in Australia. 1 We summarise Langton's argument: environmentalists would deny Aboriginal groups the benefits that flow from native title‐related agreements; environmentalists live at luxurious distance from the realities of remote and rural Aboriginal poverty and social problems; environmentalists exalt ‘noble savages’. We critique these claims on the basis that they pay inadequate attention to the structural inequities that underpin the market in native title interests and, further, deny the reality that Aboriginal groups often seek to form strategic alliances with green groups, arguing for conservation of their country on their own—or shared—terms. We argue that any appraisal of the present status of ‘green‐black’ relations needs to consider these factors seriously.     

Fasting-based estimates of insulin sensitivity in overweight and obesity: a critical appraisal

Objective: To identify simple methods to estimate the degree of insulin resistance. Research Methods and Procedures: The performance of a wide range of fasting‐based index estimates of insulin sensitivity was compared by receiver operating characteristic analysis (area under curves and their 95% confidence intervals) against the M value from euglycemic insulin clamp studies collected in the San Antonio (non‐Hispanic whites and Hispanic residents of San Antonio, TX) and European Group for the Study of Insulin Resistance (non‐diabetic white Europeans) databases (n = 638). Results: Insulin resistance differed substantially between lean (BMI < 25 kg/m²), overweight or obese (BMI ≥ 25 kg/m²), and type 2 diabetic individuals. Estimates of insulin resistance were, therefore, assessed in each group separately. In the overweight and obese subgroup (n = 302), the receiver operating characteristic performance of fasting‐based indices varied from 0.72 (0.62 to 0.82), in the case of the insulin/glucose ratio, to 0.80 (0.72 to 0.88) in the case of Belfiore free fatty acids. One superior method could not be identified; the confidence intervals overlapped, and no statistically significant differences emerged. All indices performed better when using the whole study population, with fasting plasma insulin, homeostatic model assessment, insulin/glucose ratio, quantitative insulin sensitivity check index, glucose/insulin ratio, Belfiore glycemia, revised quantitative insulin sensitivity check index, McAuley index, and Belfiore free fatty acids showing area under curves of 0.83, 0.90, 0.66, 0.90, 0.66, 0.90, 0.85, 0.83, and 0.86, respectively, because of the inclusion of very insulin sensitive (lean) and very insulin resistant cases (diabetic subjects). Discussion: In conclusion, a superior fasting‐based index estimate to distinguish between the presence and absence of insulin resistance in overweight and obesity could not be identified despite the use of the large datasets.     

Elemental and molecular detection for Quantum Dots-based immunoassays: a critical appraisal

A critical comparison between Elemental Mass Spectrometry (ICP-MS) and molecular fluorescence, as detection techniques for CdSe/ZnS Quantum Dots (QDs)-based immunoassays is presented here. Using a QDs-based progesterone immunoassay as "model" analytical system the features of both detection modes has been investigated. Minimal changes, compared to the previously developed fluorescent approach, were necessary to build the corresponding inhibition curve for the progesterone immunoassay using ICP-MS detection of cadmium (contained in the QDs core). Adequate agreement between results obtained using both elemental and molecular techniques for the determination of progesterone in cow milk has been obtained. Moreover, results from the comparison showed that fluorescence detection of the QDs is simpler, less time consuming and less expensive, but ICP-MS detection affords alternative and useful information unattainable using luminescence detection. First of all, ICP-MS allowed mass balances to be carried out (all along the sample preparation) providing an internal validation of the immunoassay procedure. Secondly, matrix-independent quantification as provided by ICP-MS enabled a direct determination of progesterone in raw milk without any further sample preparation (dilution) step. As a matter of fact, ICP-MS results showed that the quenching matrix effect suffered on bioconjugated QDs fluorescence emission (e.g. when the immunoassay was carried out directly in whole milk without any dilution) could be unequivocally attributed to nonspecific interactions between the matrix of the whole milk and the QDs surface. Finally, better sensitivity could be obtained with ICP-MS detection, IC(10)=0.028 ng/mL, versus 0.11 ng/mL using conventional fluorimetric detection, just by using lower reagents concentrations.