Immunohistochemical and Histopathological Characterization of Spina Bifida Defect Tissues Removed After Prenatal and Postnatal Surgical Repair

Background: Myelomeningocele or spina bifida is an open neural tube defect that is characterized by protrusion of the meninges and the spinal cord through a deformity in the vertebral arch and spinous process. Myelomeningocele of post-natal tissue is well described; however, pre-natal tissue of this defect has no known previous histologic characterization. We compared the histology of different forms of pre-natal myelomeningocele and post-natal myelomeningocele tissue obtained via prenatal intrauterine and postnatal surgical repairs. Methods: Pre-and post-natal tissues from spina bifida repair surgeries were obtained from lipomyelomeningocele, myeloschisis, and myelomeningocele spina bifida defects. Tissue samples were processed for H&E and immunohistochemical staining (KRT14 and p63) to assess epidermal and dermal development. Results: Prenatal skin near the defect site develops with normal epidermal, dermal, and adnexal structures. Within the grossly cystic specimens, histology shows highly dense fibrous connective tissue with complete absence of a normal epidermal development with a lack of p63 and KRT14 expression. Conclusion: Tissues harvested from prenatal and postnatal spina bifida repair surgeries appear as normal skin near the defect site. However, cystic tissues consist of highly dense fibrous connective tissue with complete absence of normal epidermal development.

Psychology of Aesthetics: Beauty, Social Media, and Body Dysmorphic Disorder

The perception of beauty is fluid within society and can morph based on cultural practices and societal interaction, such as social media exposure. The exposure to digital conference platforms has increased significantly, leading users to check their appearance constantly and find flaws in their perceived virtual appearance. Studies have shown that frequent social media use may lead to unrealistic body image ideals, a significant concern with appearance, and anxiety. Also, social media exposure can worsen body image dissatisfaction, social networking site addiction, and comorbidities of body dysmorphic disorder (BDD) such as depression and eating disorders. Additionally, excessive social media use can increase preoccupation with imagined image defects among BDD patients leading them to pursue minimally invasive cosmetic and plastic surgery procedures. This contribution aims to provide an overview of the evidence surrounding the perception of beauty, cultural aspects of aesthetics, and social media's consequences, especially on BDD's clinical specifics.

Top Skin-of-Color Publications in Dermatology

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Shifting the Standard of Beauty: Beginning of the Body Inclusive Model

Background: While the American standard of beauty idolizes unattainable thinness, social media exposure has been instrumental in crafting a more inclusive perception of beauty.

Methods: Using several websites with public data on models, we gathered body measurements and characteristics of both plus-size and the overall top 10 paid mainstream models. We then collected social media data for these models using the social media analytics tool called Social Blade. We compared social media data between plus-size and mainstream models.

Results: While plus-size models have increased BMI, the waist/hip ratio was 0.74 on average, compared to 0.71 in mainstream models. The average social media following among the top 10 plus-size models was 3.8 million compared to 38 million amongst the top 10 mainstream models (p = 0.039). There was no significant difference between the average likes per post, average comments per post, and total posts between the top mainstream models and top plus-size models (p-values 0.11, 0.12, and 0.15, respectively).

Conclusion: With the changing societal body image in America, plus-size models have gained in popularity and positively impacted a body-inclusive model of beauty. However, the mainstream model still prevails as the social media powerhouse of influence.

Social Media as a Medium for Dermatologic Education

Purpose of Review

We explore the utility of social media platforms as educational tools in dermatology, providing a summary of how these sites are used by the public and dermatologists alike, and demonstrating ways these findings may be applied for educational purposes.

Recent Findings

Over half of the world’s population utilizes social media platforms. More recently, these platforms have increasingly been used for educational purposes. In the field of dermatology, a large portion of the educational content is coming from users with no formal medical or dermatologic training.

Summary

Each of the top five social media platforms in the world (Twitter, Instagram, TikTok, YouTube, and Facebook) has unique qualities which people may utilize to educate fellow users. As more of the population seeks online health information and education, it is important that dermatologists, while taking ethical considerations into account, become more comfortable facilitating educational content on social media.

Type III Cutaneous Atypical Meningioma of the Scalp

Cutaneous meningiomas can be a diagnostic challenge, as they are not only found very rarely in extracranial sites, including the skin, but also because of the histopathologic overlap with several other spindle cell tumors. Cutaneous meningiomas are divided into type I (congenital), type II (ectopic) and type III (via a direct extension) lesions. We present a rare case of atypical meningioma of the skin in a 71-year-old female. A patient presented with a painful and enlarging lesion on the left central frontal scalp. Biopsy showed bone and soft tissue with involvement of a spindle cell neoplasm, consisting of whorled nests with atypical features, including variably increased mitotic index, areas of hypercellularity, and sheeted architecture. The overall findings were consistent with an atypical meningioma (WHO grade 2). Atypical meningiomas constitute only 5 - 15% of all meningiomas. A skull MRI was later performed, which demonstrated a left frontal tumor consistent with an atypical meningioma that had eroded through the skull. Dermatopathologists should consider cutaneous meningioma as a differential diagnosis of spindle cell neoplasms of the skin and subcutaneous tissue in head and neck. This article is protected by copyright. All rights reserved.

Indoor tanning: Evidence surrounding advertised health claims

Indoor tanning continues to remain common, despite evidence of an increased risk of skin cancer from artificial ultraviolet (UV) radiation. In the hopes of gaining customers, the tanning bed industry has marketed health benefits of indoor tanning such as increased vitamin D production, development of a base tan, enhanced mood, and treatment of certain dermatologic conditions. To better educate their patients, providers need a comprehensive reference reviewing the evidence that support or oppose these claims. In this work, we conducted an evidence-based review of the literature to identify and grade studies that investigate health claims related to UV exposure. Results indicate that there is little evidence to support each of these proposed health benefits. Tanning beds emit primarily UVA radiation, which is relatively ineffective at activating vitamin D or mood enhancing pathways, and the effects are minimal in regard to tanning beds generating a protective base tan or treating dermatologic conditions compared with the increased risk of skin cancer. Health care providers must continue to warn and educate patients about the misleading information propagated by the tanning bed industry as well as about the dangers of artificial UV radiation.

Social Media and Ethical Challenges for the Dermatologist

Purpose of Review

The purpose of review is to provide guidance on the use of social media within the context of dermatology and discuss its ethical, professional, and legal implications in education, mentorship, networking, business, and clinical settings.

Recent Findings

Despite its fundamental value as a means of communication and knowledge sharing, social media carries legal, ethical, and professional challenges. Healthcare providers have run into issues such as misinformation, conflicts of interest, and overstepping patient-physician boundaries when using social media. An interesting finding is that dermatologists commonly engage with an online audience through social media marketing or being an influencer to improve business and extend their reach to clients; however, this warrants formal training and the need to monitor their own online presence to prevent legal consequences.

Summary

Social media has become integral in everyday life; billions of people now receive information and stay connected with each other through social platforms. Within medicine, social media has enhanced various aspects of healthcare, such as professional networking, patient care, and patient education. In dermatology, social media allows dermatologists to promote their businesses and services through patient testimonials, posting advice on blogs, and networking with a large audience of potential patients. However, having a social media presence must be exercised with care, purpose, and transparency to maximize benefits and minimize harmful consequences. This is especially important when inappropriate social media posts by physicians can be scrutinized for breaching patient confidentiality, violating privacy, financial conflicts of interest, and possibly disseminating incorrect information.

Commonly Used Over the Counter Therapies for Hair Growth in Skin of Color: An Evidenced-Based Review

BACKGROUND

Given the immense psychosocial effects of hair loss as well as patient preference for treatment type, it is common for patients to turn to alternative medicine to improve their conditions. However, the commonly used alternative treatments can vary greatly between patients and particularly among skin of color populations.

OBJECTIVE

In this work, we performed a scoping review of the evidence behind alternative topical treatments for hair loss used by skin of color patients. Methods & Materials: We conducted a comprehensive search using PubMed to identify relevant studies.

RESULTS

Results show a diverse variety of hair growth products used; however, only a few are supported by randomized controlled trials, case reports, pilot studies, and animal studies with some important limitations.

CONCLUSION

This information will be exceedingly useful for physicians so they may relay accurate evidence on these haircare practices to their skin of color patients. J Drugs Dermatol. 2021;20(7):726-731. doi:10.36849/JDD.5689.

Emerging topical therapies to treat pigmentary disorders: an evidence-based approach

BACKGROUND

Hyperpigmentation disorders are commonly encountered in dermatology clinics. The use of prescription-grade and over-the-counter topical lightening agents has increased in popularity, leading to a substantial growth of research over the past decade.

OBJECTIVE

We seek to review clinical studies evaluating the use of different Rx-grade and OTC ingredients in treating hyperpigmentation.

METHODS AND MATERIALS

A comprehensive search on PubMed was conducted to identify patient-based evidence on the most common ingredients used as topical lightening agents: arbutin, ascorbic acid, cysteamine, hydroquinone, kojic acid, niacinamide, retinoids, and triple-combination therapy. The topicals were classified as either prescription-grade or over-the-counter.

RESULTS

Varying levels of evidence support the use of topicals in treating hyperpigmentation. There were more clinical trials examining Rx-grade products than OTC products. Mild but tolerated side effects are noted in many of these agents.

CONCLUSION

Careful monitoring and adjustment of doses will be needed to maximize skin lightening benefits and minimize side effects.

Scoping Review of Therapeutic Strategies for Keloids and Hypertrophic Scars

Background:

Keloids are an abnormal proliferation of scars that can involve large areas of tissue beyond the original injury site. Hypertrophic scars are similar clinically, but do not exceed the original scar limits. These scarring abnormalities can cause noxious symptoms such as pain, tenderness, itching, and ulcerations. The aim of this review is to discuss current therapies for both types of abnormal scarring, and to determine if guidelines can be provided for excisional treatment with adjuvant therapies versus non-excisional methods.

Methods:

A systematic literature search was performed through the Web of Science database. The search revolved around keywords such as “keloid,” “hypertrophic scars,” and “treatment.” Articles were reviewed and screened for inclusion and exclusion criteria. The review focuses on an analysis and summarization of randomized control trials regarding keloid or hypertrophic scar treatments.

Results:

The original searches produced 1161 and 1275 articles for keloid and hypertrophic scars, respectively. In total, 316 duplicates were found. After accounting for 2014–2019 publication time, 655 keloid and 893 hypertrophic scar articles were reviewed. This resulted in 15 articles that pertained to treatment and randomized control trials.

Conclusions:

Keloids and hypertrophic scars present a clinical challenge. Based on qualitative review of recurrence, neither excision plus adjuvant therapy or nonsurgical treatments can be recommended preferentially at this time. More research is needed to determine if recurrence rate bias exists between the treatment regimens, as excisional treatment plus adjuvant therapy is reserved for refractory scars.

Characterization of immune cells found in keloid versus normal skin tissue

Keloids are abnormal scar formation that extends beyond the confines of the original injury. Immune cell infiltration is associated with keloid pathogenesis, but the exact mechanisms remain unknown. We aim to characterize the immune profile of keloid skin compared to normal skin in order to further understand the role of specific immune subsets in keloid formation. One abdominal normal skin sample and five keloid samples (four ear and one shoulder) were obtained from the Plastic Surgery clinics and the University of Colorado Biorepository Core Facility. Paraffin-embedded samples were stained with CD19+, CD20+, CD3+, CD8+ and FoxP3+ by the Human Immunology and Immunotherapy Initiative. The multiplex immunohistochemistry slides were scanned using Vectra 3 (PerkinElmer, MA, US) and captured images were analyzed with InForm Tissue Finder, phenotpr, and phenoptrReports (Akoya Biosciences, CA, US). CD20+ and CD19+ B cells were significantly increased in keloid tissue compared to normal skin (14.50% and 14.20% vs 6.47% and 7.56%), respectively. In contrast, no significant difference was observed in the percentage of CD3+ and CD8+ cell subsets in keloids compared to normal skin (12.92% and 4.98% vs 8.19% and 4.04%), respectively. Moreover, there was a significant increase in FoxP3+ positive cells found in keloid scars (9.68%) compared to normal skin (2.89%). Further studies examining the role of B cells and FoxP3+ cells in keloid pathogenesis are warranted.

Plasmid-like DNAs in the commercially important mushroom genus Agaricus

Two unique plasmid-like DNA components were localized in isolated mitochondria of the commercially important mushroom genus Agaricus: pEM (7.35 ± 0.15 kilobases) and pMPJ (3.65 ± 0.15 kilobases). These DNA moieties were linear; pEM possessed regions of terminal inverted repeated sequences. No homology was detected between pEM or pMPJ DNA and the nuclear or mitochondrial genomes. No homology existed between pEM and pMPJ. This suggests independent replication of pEM and pMPJ. Restriction endonuclease digests indicated that pEM consisted of two components (pEM1 and pEM2) with uniquely different restriction sites and copy number.

Molecular Beams with Energies above One Electron Volt

By using as sources supersonic jets of hydrogen or helium containing small concentrations of heavier molecules we have been able to obtain molecular beams with kinetic energies of the heavy molecules well into the range above I electron volt. A variety of molecules have been successfully accelerated. Intensities of 10(16) to 10(17) heavy molecules per steradian-second have been achieved at these high energies.

Localization of the Mating Type Gene in Agaricus bisporus

The cultivated mushroom Agaricus bisporus is secondarily homothallic. Most basidia produce two basidiospores, each of which receives two of the four postmeiotic nuclei. Usually, the two packaged nuclei carry compatible mating types. Previous studies suggested that there may be only a single mating type locus in A. bisporus. In this study, we determined whether the mating type segregated as a single Mendelian determinant in a cross marked with 64 segregating molecular markers. To score mating types, each of the 52 homokaryotic offspring from this cross was paired with each of the two progenitor homokaryons. Compatible matings were identified by the formation of genetically stable heterokaryons which were verified by assay of restriction fragment length polymorphisms (RFLPs). Data for screening mycelial interactions on petri plates as well as fruit body formation were compared with the RFLP results. Mating types of 43 of the 52 homokaryotic offspring were determined on the basis of RFLP analysis. Our results indicate (i) there is a segregating mating type gene in A. bisporus, (ii) this mating type gene is on the largest linkage group (chromosome I), (iii) mycelial interactions on petri plates were associated with heterokaryon formation under selected conditions, (iv) fruit body formation was dependent upon the mating type gene, and (v) compatible mating types may not always be sufficient for fruiting.

Mitochondrial Haplotype Influences Mycelial Growth of Agaricus bisporus Heterokaryons

We evaluated the influence of mitochondrial haplotype on growth of the common button mushroom Agaricus bisporus. Ten pairs of heterokaryon strains, each pair having the same nuclear genome but different mitochondrial genomes, were produced by controlled crosses among a group of homokaryons of both wild and commercial origins. Seven genetically distinct mitochondrial DNA (mtDNA) haplotypes were evaluated in different nuclear backgrounds. The growth of heterokaryon pairs differing only in their mtDNA haplotypes was compared by measuring mycelial radial growth rate on solid complete yeast medium (CYM) and compost extract medium and by measuring mycelial dry weight accumulation in liquid CYM. All A. bisporus strains were incubated at temperatures similar to those utilized in commercial production facilities (18, 22, and 26(deg)C). Statistically significant differences were detected in 8 of the 10 heterokaryon pairs evaluated for one or two of the three growth parameters measured. Some heterokaryon pairs showed differences in a single growth parameter at all three temperatures of incubation, suggesting a temperature-independent difference. Others showed differences at only a single temperature, suggesting a temperature-dependent difference. The influence of some mtDNA haplotypes on growth was dependent on the nuclear genetic background. Our results show that mtDNA haplotype can influence growth of A. bisporus heterokaryons in some nuclear backgrounds. These observations demonstrate the importance of including a number of mitochondrial genotypes and evaluating different nuclear-mitochondrial combinations of A. bisporus in strain improvement programs.

Intervention Strategies and Agents Mediating the Prevention of Xenorejection

Xenotransplantation, the transplantation of cells, tissues, and/or organs across species, has proven to be an enormous challenge, resulting in only limited achievements over the last century. Unlike allotransplantation, the immunologic barriers involved in xenotransplant rejection are aggressive and usually occur within minutes in a hyperacute fashion. The use of organs from phylogenetically related concordant species may not be practical. Discordant xenotransplantation is characterized by hyperacute graft rejection, and to use nonprimate discordant organs for human benefit will require manipulation of the taxonomic differences. The hyperacute rejection process is primarily due to the attachment of preformed xenoreactive antibodies to the donor vascular endothelium, which results in hyperactivation of the complement system beyond the control of the natural complement regulatory proteins. Understanding the complex and diverse immune components involved in hyperacute, acute, and accelerated rejections has resulted in the development of different hematologic and molecular strategies. Plasmapheresis has been used to remove xenoantibodies, and xenoperfusion techniques are used to create a suitable and familiar environment for the xenograft. Various molecular approaches, such as the development of transgenic animals expressing human complement regulatory proteins such as CD59 or decay accelerating factor (DAF), to downregulate complement activation or the production of pigs lacking the xenoreactive antigen by knockout of the Gal alpha-1,3-galactosyl transferase gene have also been attempted. A combination of these techniques together with the administration of soluble complement inhibitors such as the vaccinia virus complement control protein (VCP) may well contribute to prolong graft survival. However, various issues including the possible emergence of new viral infections have confounded the topic of xenotransplantation. Here the different modulatory approaches and agents mediating interventions in xenorejection are discussed.

Broadcasts of wing-fanning vibrations recorded from calling male Ceratitis capitata (Diptera: Tephritidae) increase captures of females in traps

Female Mediterranean fruit flies, Ceratitis capitata (Wiedemann), from the sterile-male rearing facility in El Pino, Guatemala, were exposed to broadcasts of wing-fanning vibrations recorded from males engaged in calling behavior to investigate the feasibility of developing a female-selective acoustic trap. The recorded signals had frequent amplitude fluctuations and peak frequencies approximately 350 Hz, typical of signals observed in previous studies of Mediterranean fruit fly acoustic behavior. Females did not exhibit long-distance phonotaxis, but remained near a speaker significantly longer when the sounds were broadcast at 103-107 dB than when the speaker was silent. In addition, significantly higher percentages of females were captured by yellow adhesive traps next to a broadcasting speaker than by traps next to a silent mimic. Additional bioassays were conducted with synthetic, 350-Hz tones produced by a thermoacoustic tube as well as with silent mimics of the different sound sources to examine the relative responsiveness of female Mediterranean fruit flies to traps with different acoustic and visual features. The visual attributes of the different sound source assemblies significantly affected capture rates. The range over which the broadcast significantly increased the percentage of female captures was <0.5 m, which may limit the utility of these acoustic cues in large-scale trapping programs. However, the findings of this study do justify further testing of whether optimized short-range acoustic signals could be used to augment longer range pheromonal and visual cues to improve the efficacy of female-selective traps.

Acoustic detection of termite infestations in urban trees

A portable, low-frequency acoustic system was used to detect termite infestations in urban trees. The likelihood of infestation was rated independently by a computer program and an experienced listener that distinguished insect sounds from background noises. Because soil is a good insulator, termite sounds could be detected easily underneath infested trees, despite the presence of high urban background noise. Termite sounds could be detected also in trunks, but background noise often made it difficult to identify termite signals unambiguously. High likelihoods of termite infestation were predicted at four live oak (Quercus virginiana Mill, Fagacae), two loblolly pine (Pinus taeda L., Pinacae), and two baldcypress (Taxodium distichum Rich. Pinacae) trees that wood-baited traps had identified as infested with Coptotermes formosanus Shiraki. Infestations also were predicted at two pine trees with confirmed recoveries of Reticulitermes flavipes (Kollar). Low likelihoods of infestation were predicted in four oak trees where no termites were found. Additional tests were conducted in anechoic environments to determine the range of acoustic detectability and the feasibility of acoustically estimating termite population levels. There was a significant regression between the activity rate and the number of termites present in a wood trap block, with a minimum detectable number of approximately 50 workers per liter of wood. The success of these field tests suggests that currently available acoustic systems have considerable potential to detect and monitor hidden infestations of termites in urban trees and around building perimeters in addition to their present uses to detect and monitor termite infestations in buildings.

Divergence in fitness and evolution of drug resistance in experimental populations of Candida albicans

The dissemination and persistence of drug-resistant organisms in nature depends on the relative fitness of sensitive and resistant genotypes. While resistant genotypes are expected to be at an advantage compared to less resistant genotypes in the presence of drug, resistance may incur a cost; resistant genotypes may be at a disadvantage in the absence of drug. We measured the fitness of replicate experimental populations of the pathogenic yeast Candida albicans founded from a single progenitor cell in a previous study (L. E. Cowen, D. Sanglard, D. Calabrese, C. Sirjusingh, J. B. Anderson, and L. M. Kohn, J. Bacteriol. 182:1515-1522, 2000) and evolved in the presence, and in the absence, of the antifungal agent fluconazole. Fitness was measured both in the presence and in the absence of fluconazole by placing each evolved population in direct competition with the drug-sensitive ancestor and measuring the reproductive output of each competitor in the mixture. Populations evolved in the presence of drug diverged in fitness. Any significant cost of resistance, indicated by reduced fitness in the absence of drug, was eliminated with further evolution. Populations evolved in the absence of drug showed more uniform increases in fitness under both conditions. Fitness in the competition assays was not predicted by measurements of the MICs, doubling times, or stationary-phase cell densities of the competitors in isolation, suggesting the importance of interactions between mixed genotypes in competitions.

Identification and analysis of the myosin superfamily in Drosophila: a database approach

The recent sequencing of the genome of Drosophila melanogaster has provided a valuable resource for mining the database for genes of interest. We took advantage of this opportunity in an attempt to identify novel myosins in Drosophila and confirm the presence of the previously identified myosins from classes I, II, III, V, VI, and VII. The Drosophila database annotators predicted the structure of three additional proteins which we identified as novel unconventional myosins, two of which fell into classes XV and XVIII, respectively. Our own efforts predicted the presence of four additional partial sequences that appear to be myosin proteins which did not fall into any specific class. In the future comparative genomics will hopefully lead to the placement of these myosins into new classes.

Multilocus genotyping indicates that the ability to invade the bloodstream is widespread among Candida albicans isolates

Multilocus genotyping was used to compare populations of Candida albicans from oral mucosa and blood. No significant differences in allele frequencies between the two samples were detected, and in a dendrogram of genotypic similarities, genotypes from both types of samples were finely interspersed. This is evidence for widespread distribution of invasive potential.

The progression of benign prostatic hyperplasia: examining the evidence and determining the risk

BACKGROUND

Benign prostatic hyperplasia (BPH) is often associated with enlargement of the prostate gland, lower urinary tract symptoms, decreased urinary flow and a reduced quality of life. Furthermore, if the symptoms associated with BPH are left untreated, serious complications, such as acute urinary retention, may ensue. Evidence is emerging from long-term clinical studies to suggest that BPH is a progressive disease, with some patients progressing much more rapidly than others.

OBJECTIVE

This article aims to explore the natural history of BPH progression from a molecular, pathological and clinical perspective, with emphasis on the key clinical evidence to support the progressive nature of this disease. How our increased understanding of the disease and of the risk factors for BPH progression might be applied to improve current management practices are also discussed.

CONCLUSION

Strategies to identify patients most at risk and guidelines directed towards long-term management, in addition to short-term treatment, may be useful in helping to prevent BPH progression.

Infrequent genetic exchange and recombination in the mitochondrial genome of Candida albicans

Previous analyses of diploid nuclear genotypes have concluded that recombination has occurred in populations of the yeast Candida albicans. To address the possibilities of clonality and recombination in an effectively haploid genome, we sequenced seven regions of mitochondrial DNA (mtDNA) in 45 strains of C. albicans from human immunodeficiency virus-positive patients in Toronto, Canada, and 3 standard reference isolates of C. albicans, CA, CAI4, and WO-1. Among a total of 2,553 nucleotides in the seven regions, 62 polymorphic nucleotide sites and seven indels defined nine distinct mtDNA haplotypes among the 48 strains. Five of these haplotypes occurred in more than one strain, indicating clonal proliferation of mtDNA. Phylogenetic analysis of mtDNA haplotypes resulted in one most-parsimonious tree. Most of the nucleotide sites undergoing parallel change in this tree were clustered in blocks that corresponded to sequenced regions. Because of the existence of these blocks, the apparent homoplasy can be attributed to infrequent, past genetic exchange and recombination between individuals and cannot be attributed to parallel mutation. Among strains sharing the same mtDNA haplotypes, multilocus nuclear genotypes were more similar than expected from a random comparison of nuclear DNA genotypes, suggesting that clonal proliferation of the mitochondrial genome was accompanied by clonal proliferation of the nuclear genome.

Absence of perilipin results in leanness and reverses obesity in Lepr(db/db) mice

Obesity is a disorder of energy balance. Hormone-sensitive lipase (HSL) mediates the hydrolysis of triacylglycerol, the major form of stored energy in the body. Perilipin (encoded by the gene Plin), an adipocyte protein, has been postulated to modulate HSL activity. We show here that targeted disruption of Plin results in healthy mice that have constitutively activated fat-cell HSL. Plin -/- mice consume more food than control mice, but have normal body weight. They are much leaner and more muscular than controls, have 62% smaller white adipocytes, show elevated basal lipolysis that is resistant to beta-adrenergic agonist stimulation, and are cold-sensitive except when fed. They are also resistant to diet-induced obesity. Breeding the Plin -/- alleles into Leprdb/db mice reverses the obesity by ncreasing the metabolic rate of the mice. Our results demonstrate a role for perilipin in reining in basal HSL activity and regulating lipolysis and energy balance; thus, agents that inactivate perilipin may prove useful as anti-obesity medications.

Bicalutamide monotherapy compared with castration in patients with nonmetastatic locally advanced prostate cancer: 6.3 years of followup

PURPOSE

Nonsteroidal antiandrogen monotherapy may be a treatment option for some patients with advanced prostate cancer. We report a survival and safety update from an analysis of 2 studies in which patients with nonmetastatic (M0) locally advanced disease were treated with either 150 mg. bicalutamide monotherapy or castration.

MATERIALS AND METHODS

Data from 2 open label, multicenter studies of identical design were pooled according to protocol. Patients with stage T3/4 prostate cancer were randomized to receive 150 mg. bicalutamide daily or castration (orchiectomy or 3.6 mg. goserelin acetate every 28 days) in a 2:1 ratio.

RESULTS

A total of 480 patients with locally advanced prostate cancer were randomized to treatment. After a median followup of 6.3 years mortality was 56%. There was no statistically significant difference between the 2 groups in overall survival (hazard ratio 1.05, upper 1-sided 95% confidence limit 1.31, p = 0.70) or time to progression (1.20, 1.45, p = 0.11). There were statistically significant benefits in the bicalutamide monotherapy group in the 2 quality of life parameters of sexual interest (p = 0.029) and physical capacity (p = 0.046). The highest incidences of adverse events were the pharmacological side effects of hot flashes in the castration group, and breast pain and gynecomastia in the bicalutamide group. The incidences of other types of adverse events were low. Bicalutamide was well tolerated, with few drug related withdrawals from study, and no new safety issues were identified during this longer followup.

CONCLUSIONS

Monotherapy with 150 mg. bicalutamide is an attractive alternative to castration in patients with locally advanced prostate cancer for whom immediate hormone therapy is indicated.

Monte Carlo methods in electronic structures for large systems

Quantum Monte Carlo methods have recently made it possible to calculate the electronic structure of relatively large molecular systems with very high accuracy. These large systems range from positron complexes [NH(2),Ps] with approximately 10 electrons to C(20) isomers with 120 electrons, to silicon crystal structures of 250 atoms and 1000 valence electrons. The techniques for such calculations and a sampling of applications are reviewed.

A randomised comparison of 'Casodex' (bicalutamide) 150 mg monotherapy versus castration in the treatment of metastatic and locally advanced prostate cancer

OBJECTIVES

To evaluate the efficacy and tolerability of 'Casodex' monotherapy (150 mg daily) for metastatic and locally advanced prostate cancer.

METHODS

A total of 1,453 patients with either confirmed metastatic disease (M1), or T3/T4 non-metastatic disease with elevated prostate-specific antigen (M0) were recruited into one of two identical, multicentre, randomised studies to compare 'Casodex' 150 mg/day with castration. The protocols allowed for combined analysis.

RESULTS

At a median follow-up period of approximately 100 weeks for both studies, 'Casodex' 150 mg was found to be less effective than castration in patients with metastatic disease (M1) at entry (hazard ratio of 1.30 for time to death) with a difference in median survival of 6 weeks. In symptomatic M1 patients, 'Casodex' was associated with a statistically significant improvement in subjective response (70%) compared with castration (58%). Analysis of a validated quality-of-life questionnaire proved an advantage for 'Casodex' in sexual interest and physical capacity. 'Casodex' had a substantially lower incidence of hot flushes compared to castration (6-13% compared with 39-44%) and the most commonly reported adverse events were those expected for a potent antiandrogen. However, in patients with M0 disease at entry, the data are still immature with only 13% of M0 patients having died. An initial analysis of this immature data has suggested that the results in these patients may be different to those obtained in patients with M1 disease. A further survival analysis in patients with M0 disease is therefore planned when the data are more mature.

CONCLUSIONS

'Casodex' 150 mg is less effective than castration in patients with M1 disease. However, 'Casodex' has shown a benefit in terms of quality of life and subjective response when compared to castration and has an acceptable tolerability profile. Thus 'Casodex' 150 mg monotherapy is an option for patients with M1 prostate cancer for whom surgical or medical castration is not indicated or is not acceptable.

Follicular lymphoma can be distinguished from benign follicular hyperplasia by flow cytometry using simultaneous staining of cytoplasmic bcl-2 and cell surface CD20

The distinction between benign follicular hyperplasia (FH) and follicular lymphoma (FL) is sometimes problematic. We wanted to determine whether the expression of bcl-2 of FH was quantitatively different from that of FL, using surface CD20 expression as a discriminator of the various lymphoid compartments. Lymph node cell suspensions from 12 cases of FH and 17 cases of FL were analyzed by flow cytometry using a combined surface CD20 and intracellular bcl-2 staining. CD20- T cells in FH demonstrated the same bcl-2 expression as the CD20+ mantle cells, but the bright CD20+ germinal center cells showed near absence of bcl-2 expression. In contrast, the neoplastic cells of FL showed greater bcl-2 expression than the T cells of the same tumors and all cell populations of FH. This difference was particularly significant between the neoplastic B cells of FL and the germinal center cells of FH. The combined analysis of CD20 and bcl-2 should be useful for the differential diagnosis between FH and FL and particularly applicable to limited samples or when B-cell clonality is in question. Whether the quantitation of bcl-2 expression can be of further discriminatory value in malignant lymphomas remains to be determined.

Numerical studies of blood shear and washing in a continuous flow ventricular assist device

The third prototype of a continuous flow ventricular assist device (CF3) is being developed and tested for implantation in humans. The blood in the pump flows through a fully shrouded four bladed impeller (supported by magnetic bearings) and through small clearance regions on either side of the impeller. Computational fluid dynamics (CFD) solutions for this flow have been obtained by using TascFlow, a software package available from AEA Technology, UK. These flow solutions have been used to estimate the shear stresses on the blood in the pump and, hence, to minimize hemolysis. In addition, the solutions are informative for achieving a design that will provide good washing of the blood to minimize the possibility of stagnation points that can lead to thrombosis. This study presents numerical studies of these phenomena in the CF3. The calculated shear rate results are compared with values published in the open literature. The comparisons indicate that hemolysis will not be a problem with CF3, which is in agreement with preliminary experimental measurements. Flow studies are being conducted to determine the optimal size of the clearance regions.

Spontaneous subcapsular renal haemorrhage presenting with pleuritic chest pain

We present an unusual case of spontaneous renal subcapsular haematoma in a normal kidney presenting with pleuritic chest pain and mimicking pulmonary embolism. The literature suggests that the majority of these cases occur in association with renal tumours and that the diagnosis can best be made by computed tomographic scanning. Treatment is expectant but because of the high incidence of tumours, nephrectomy is usually necessary.

Computational flow study of the continuous flow ventricular assist device, prototype number 3 blood pump

A computational fluid dynamics study of blood flow in the continuous flow ventricular assist device, Prototype No. 3 (CFVAD3), which consists of a 4 blade shrouded impeller fully supported in magnetic bearings, was performed. This study focused on the regions within the pump where return flow occurs to the pump inlet, and where potentially damaging shear stresses and flow stagnation might occur: the impeller blade passages and the narrow gap clearance regions between the impeller-rotor and pump housing. Two separate geometry models define the spacing between the pump housing and the impeller's hub and shroud, and a third geometry model defines the pump's impeller and curved blades. The flow fields in these regions were calculated for various operating conditions of the pump. Pump performance curves were calculated, which compare well with experimentally obtained data. For all pump operating conditions, the flow rates within the gap regions were predicted to be toward the inlet of the pump, thus recirculating a portion of the impeller flow. Two smaller gap clearance regions were numerically examined to reduce the recirculation and to improve pump efficiency. The computational and geometry models will be used in future studies of a smaller pump to determine increased pump efficiency and the risk of hemolysis due to shear stress, and to insure the washing of blood through the clearance regions to prevent thrombosis.

Baclofen increases the soleus stretch reflex threshold in the early swing phase during walking in spastic multiple sclerosis patients

The effect of baclofen on walking performance was examined in nine spastic multiple sclerosis patients. In addition, nine healthy subjects were tested as controls. The modulation of the short latency soleus stretch reflex was closer to normal with baclofen compared to the recordings without baclofen, the modulation index being 74% (range: 60 - 100) with baclofen and 62% (range: 20 - 100) without baclofen, P=0.03. In healthy subjects the modulation index was 100% (range: 52 - 100). In the early swing phase the threshold of the soleus stretch reflex was significantly higher during baclofen medication being 139 deg/s (range: 63 - 302) compared with 93 deg/s (range: 37 - 187) without baclofen, P=0.004. The relation between the stretch velocity (input) and the amplitude of the stretch reflex (output) in early swing phase was unchanged being 0. 27 microVs/deg (range: 0.1 - 1.51) in patients with baclofen and 0. 24 microVs/deg (range: 0.08 - 0.79) without baclofen, P=0.25. Baclofen induced no change in input - output properties of the stretch reflex during walking compared with findings in a sitting position at matched EMG activity. There was a significant correlation between clinical spasticity score and stretch reflex threshold in the early swing phase (rho=-0.61, P=0.04) and between clinical spasticity score and the slope of the best linear fit in the early swing phase (rho=0.72, P=0.009).

Evolution of drug resistance in experimental populations of Candida albicans

Adaptation to inhibitory concentrations of the antifungal agent fluconazole was monitored in replicated experimental populations founded from a single, drug-sensitive cell of the yeast Candida albicans and reared over 330 generations. The concentration of fluconazole was maintained at twice the MIC in six populations; no fluconazole was added to another six populations. All six replicate populations grown with fluconazole adapted to the presence of drug as indicated by an increase in MIC; none of the six populations grown without fluconazole showed any change in MIC. In all populations evolved with drug, increased fluconazole resistance was accompanied by increased resistance to ketoconazole and itraconazole; these populations contained ergosterol in their cell membranes and were amphotericin sensitive. The increase in fluconazole MIC in the six populations evolved with drug followed different trajectories, and these populations achieved different levels of resistance, with distinct overexpression patterns of four genes involved in azole resistance: the ATP-binding cassette transporter genes, CDR1 and CDR2; the gene encoding the target enzyme of the azoles in the ergosterol biosynthetic pathway, ERG11; and the major facilitator gene, MDR1. Selective sweeps in these populations were accompanied by additional genomic changes with no known relationship to drug resistance: loss of heterozygosity in two of the five marker genes assayed and alterations in DNA fingerprints and electrophoretic karyotypes. These results show that chance, in the form of mutations that confer an adaptive advantage, is a determinant in the evolution of azole drug resistance in experimental populations of C. albicans.

The changing pattern of mortality and morbidity from radical cystectomy

OBJECTIVES

To examine the morbidity and mortality of radical cystectomy as currently practised, and to compare the findings with historical data.

PATIENTS AND METHODS

The operative mortality and early and late complications were recorded in 101 consecutive patients (median age 65 years, range 38-81; 33 aged >70 years) undergoing radical cystectomy between April 1992 and October 1997. Fifteen patients had relapsed after previous radical radiotherapy.

RESULTS

The median postoperative stay was 14 days (range 8-44). There were two deaths within 60 days of surgery (of patients aged 46 and 59 years) from respiratory failure and sepsis, respectively. The mortality in the elderly was not more than in other age groups. The early morbidity included two cases of lower limb insufficiency, both in the salvage cystectomy group, where the morbidity was significantly higher than in those undergoing primary cystectomy (chi-squared, P<0.01). Three patients underwent early re-exploration. There were four clinically significant episodes of deep vein thrombosis and two pulmonary emboli that were not fatal.

CONCLUSION

As currently practised, radical cystectomy is associated with a lower mortality (<2%) and morbidity than described previously. The added morbidity of salvage cystectomy and the acceptable mortality of primary cystectomy suggests that the treatment of choice for muscle-invasive disease is primary cystectomy, with external beam radiotherapy reserved for those patients unfit for major surgical intervention. Age alone should no longer be considered a contraindication to cystectomy.