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1.
J Clin Aesthet Dermatol ; 16(12): 18-30, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38125668

RESUMEN

Background: The skin, our body's largest organ, hosts a complex microbiome that plays a pivotal role in maintaining health and protecting against pathogens. Even slight disruptions to this delicate balance can influence skin health and disease. Among the diverse microbial community, Cutibacterium acnes (C. acnes) subspecies defendens is known for its positive contribution to skin health. However, the interaction between living microbe probiotics and wound healing after aesthetic procedures, such as microneedling, remains unexplored. Methods: Our study included 40 participants with acne scars who underwent four microneedling sessions spaced three weeks apart. They were randomly assigned to Group 1, receiving a regimen with live C. acnes defendens strain XYCM42, or Group 2, following a conventional skincare routine with a cleanser, moisturizer, and sunscreen. Our study assessed various endpoints, including the Clinician's Global Aesthetic Improvement Scale (CGAIS), clinical safety, improvement in acne scars using Goodman and Baron's Qualitative and Quantitative Acne Scars Grading Scale and Subject's Global Aesthetic Improvement Scale (SGAIS). Results: Our analysis of live and photo grading data for CGAIS unveiled a statistically significant difference between the two groups, with Group 1 (XYCM42-based regimen) showing remarkable improvement. A similar positive trend was observed in the photo grading for CGAIS. Additionally, participant diaries indicated that Group 1 experienced a faster decline in posttreatment parameters, including erythema, swelling, burning/tingling, and itching. Conclusion: Integrating a microbiome-optimized, probiotic XYCM42-based regimen with microneedling demonstrated a high safety profile and enhanced treatment outcomes. These findings mark a milestone in aesthetic dermatology, supporting innovative microbiome-based approaches to improve skin health and aesthetics.

2.
Proc Biol Sci ; 290(2011): 20232222, 2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-37989243

RESUMEN

Females and males may have distinct phenotypic optima, but share essentially the same complement of genes, potentially leading to trade-offs between attaining high fitness through female versus male reproductive success. Such sexual antagonism may be particularly acute in hermaphrodites, where both reproductive strategies are housed within a single individual. While previous models have focused on simultaneous hermaphroditism, we lack theory for how sexual antagonism may play out under sequential hermaphroditism, which has the additional complexities of age-structure. Here, we develop a formal theory of sexual antagonism in sequential hermaphrodites. First, we construct a general theoretical overview of the problem, then consider different types of sexually antagonistic and life-history trade-offs, under different modes of genetic inheritance (autosomal or cytoplasmic), and different forms of sequential hermaphroditism (protogynous, protoandrous or bidirectional). Finally, we provide a concrete illustration of these general patterns by developing a two-stage two-sex model, which yields conditions for both invasion of sexually antagonistic alleles and maintenance of sexually antagonistic polymorphisms.


Asunto(s)
Evolución Biológica , Trastornos del Desarrollo Sexual , Femenino , Masculino , Humanos , Reproducción , Polimorfismo Genético , Procesos de Determinación del Sexo , Selección Genética
3.
Skin Health Dis ; 3(5): e264, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37799356

RESUMEN

Background: Acne is an inflammatory disease of the pilosebaceous unit that occurs primarily in adolescents. There is no current ideal treatment for acne vulgaris, as many mainstay prescription treatment modalities can compromise the skin microbiome or have deleterious health effects. Further research is needed to investigate novel treatment modalities that account for the importance of the skin microbiome. Other developing treatment modalities for acne are still taking a similar mode of action as current treatments by trying to eliminate Cutibacterium acnes despite growing evidence that some C. acnes strains may be symbiotic in nature. The perception that microneedling will exacerbate the disease state and trigger more acneic lesions via the spread of acne-associated microbes has hindered research investigating whether microneedling is a safe and effective treatment. This pilot clinical study challenges such perceptions by clinical assessment to determine if microneedling may produce beneficial treatment outcomes without disrupting critical skin structure or skin microbiome. Objectives: Test the safety and efficacy of microneedling as an effective treatment modality for acne vulgaris. Methods: Subjects were split into two groups, one group received three treatments 4 weeks apart, and the second group received four treatments 2 weeks apart. Subjects received an acne assessment by an expert clinical grader at all clinical visits. Results: There was a statistically significant reduction in both non-inflammatory and inflammatory lesions at the 2-month follow-up compared to the baseline for Group 1. Group 1 and Group 2 saw a decline of 48.20% and 54.00% in non-inflammatory lesions and 57.97% and 36.67% in inflammatory lesions, respectively, at their last visit compared to baseline. Conclusion: This study expands the utility of microneedling into a potential therapeutic modality for acne vulgaris. The data generated during the duration of this clinical study demonstrates that there is no scientific reason for microneedling to be contraindicated for acne. In this pilot, microneedling did not cause post-treatment complications and was seen to reduce acne lesions effectively. Thus, microneedling may have the potential to be a well-tolerated option for those suffering from acne, being a treatment that neither damages the sebaceous glands nor disrupts the skin microbiome.

4.
J Cosmet Dermatol ; 22(1): 206-213, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35403786

RESUMEN

OBJECTIVES: A microneedling pen has been cleared by the US Food and Drug Administration, indicated for improving the appearance of adult facial acne scars. The objective of this study was to assess the device's effectiveness for treating wrinkles of the face area. MATERIALS AND METHODS: Healthy adults seeking to improve the appearance of face wrinkles were enrolled (N = 35), receiving four monthly microneedling procedures by a trained aesthetician who treated the face skin per manufacturer instructions. Wrinkle assessments were performed by two trained blinded raters by comparing baseline images of each subject with images obtained at 90 days post-procedure. Subsequently, the two raters were unblinded for the Clinician's Global Aesthetic Improvement Scale (CGAIS) assessment. Subjects completed the Subject's Global Aesthetic Improvement Scale (SGAIS) and a Satisfaction Questionnaire at 30 and 90 days post-treatment. RESULTS: The study was completed by 32 subjects with a mean (SD) age of 56.3 (5.0) years. Wrinkle assessments demonstrated significant improvement in the face areas (p < 0.001). The SGAIS scores showed significant improvements after 30 and 90 days post-treatment (for each, p < 0.001). The CGAIS scores also showed significant improvements at 90 days post-treatment (p < 0.001). Most subjects reported some level of improvement in their appearance at 30 days (73.3%) and 90 days (68.8%) post-treatment. The satisfaction questionnaire showed high levels of improvement in wrinkles (93.8%), satisfaction with the treatment procedure (87.5%) and would recommend microneedling to friends and family members (80.6%) on the face and neck. CONCLUSION: Microneedling is a viable, minimally invasive option for treating wrinkles of the face. CLINICALTRIALS: gov Identifier: NCT03803059.


Asunto(s)
Técnicas Cosméticas , Envejecimiento de la Piel , Adulto , Humanos , Persona de Mediana Edad , Técnicas Cosméticas/efectos adversos , Cicatriz/terapia , Piel/patología , Resultado del Tratamiento
5.
J Cosmet Dermatol ; 22(3): 1031-1045, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36374551

RESUMEN

BACKGROUND: When formulating topical products to treat skin diseases and addressing general skin health and cosmesis, most of the focus has traditionally been placed on how any given ingredient may impact the structure, function, and health of human skin elements. However, recent research is beginning to highlight the importance of the skin microbiome in relation to certain skin conditions and general cosmesis. Cutibacterium acnes is one of the most prolific skin-specific bacterial species. Research has shown that the species is divided into subspecies, some of which are thought to be beneficial to the skin. This paper aims to determine the efficacy of strainXYCM42, a C. acnes subspecies defendens derived strain designed to improve the health and appearance of the skin. METHODS: In vitro studies were performed on human keratinocyte and fibroblast monolayers, human peripheral blood mononuclear cells (PBMC), and skin explants to elucidate the effects of live XYCM42 cells and their ferment on human skin cells and tissues. Subsequently, clinical studies were performed using XYCM42-based topical regimens designed to deliver and support the engraftment of live XYCM42 cells onto subjects' skin. Two studies were performed, a 3-week pilot study (n = 10) and a 8-week pivotal study (n = 121). In the latter, 32 subjects were enrolled for an in-clinic portion for efficacy evaluation, with clinic visits occurring at Baseline, Week 1, Week 4, and Week 8. RESULTS: In vitro data suggest that XYCM42 and its ferment filtrate have potential to provide benefits to the skin via antioxidant, anti-inflammatory, and select antimicrobial activities. Clinical observation demonstrated that a XYCM42-containing regimen supports a healthy skin environment, promotes increased skin hydration, decreases erythema, calms the skin, and regulates sebum production. CONCLUSION: These studies provide further evidence that specific strains of C. acnes, such as XYCM42, have a more beneficial function regarding skin health and appearance than was previously thought. Appropriate use of formulations derived from symbiotic strains within the skin microbiome can support the development of novel, beneficial topicals.


Asunto(s)
Acné Vulgar , Enfermedades de la Piel , Humanos , Leucocitos Mononucleares , Proyectos Piloto , Piel/microbiología , Acné Vulgar/tratamiento farmacológico , Queratinocitos , Propionibacterium acnes
6.
Evolution ; 76(9): 2191-2198, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35902334

RESUMEN

Population viscosity has long been thought to promote the evolution of altruism. However, in the simplest scenarios, the potential for altruism is invariant with respect to dispersal-a surprising result that holds for haploidy, diploidy, and haplodiploidy (arrhenotoky). Here, we develop a kin-selection model to investigate how population viscosity affects the potential for altruism in species with male paternal genome elimination (PGE), exploring altruism enacted by both females and males, and both juveniles and adults. We find that (1) PGE promotes altruistic behaviors relative to the other inheritance systems, and to a degree that depends on the extent of paternal genome expression. (2) Under PGE, dispersal increases the potential for altruism in juveniles and decreases it in adults. (3) The genetics of PGE can lead to striking differences in sex-specific potentials for altruism, even in the absence of any sex differences in ecology.


Asunto(s)
Altruismo , Evolución Biológica , Femenino , Masculino , Haploidia , Viscosidad , Animales
7.
Aesthet Surg J ; 42(10): 1154-1160, 2022 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-35397167

RESUMEN

BACKGROUND: A microneedling pen has been cleared by the US FDA and is indicated for improving the appearance of facial acne scars in adults. OBJECTIVES: The aim of this study was to assess the effectiveness of this microneedling pen for treating wrinkles. This paper focuses on the results on the neck, an area of recent importance with video meetings placing physical stress on the neck area, leading to wrinkles. METHODS: Healthy adult men and women were enrolled (N = 35). Subjects received 4 monthly microneedling procedures at depths of up to 2.5 mm. Wrinkle assessments were performed by 2 trained blinded raters by comparing images of each subject at baseline and at 90 days postprocedure. The 2 raters were unblinded for the Clinician's Global Aesthetic Improvement Scale assessment. Subjects completed the Subject's Global Aesthetic Improvement Scale and a questionnaire regarding satisfaction with the treated areas of the face and neck at 30 and 90 days posttreatment. RESULTS: The study was completed by 32 subjects. Wrinkle assessments demonstrated significant improvement in the neck areas (P < 0.001). Both Global Aesthetic Improvement Scales showed significant improvements at 90 days posttreatment (P < 0.001). Most subjects reported some level of improvement in their appearance at 30 days (73.3%) and 90 days (68.8%) posttreatment. The satisfaction questionnaire showed high levels of improvement in wrinkles (93.8%), satisfaction with the results (87.5%), and would recommend microneedling to friends and family members (80.6%). CONCLUSIONS: Microneedling is a viable, minimally invasive option for treating wrin kles of the neck.


Asunto(s)
Acné Vulgar , Envejecimiento de la Piel , Adulto , Cicatriz/terapia , Femenino , Humanos , Masculino , Cuello , Resultado del Tratamiento
8.
Evolution ; 76(2): 292-309, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34773705

RESUMEN

Females and males may face different selection pressures, such that alleles conferring a benefit in one sex may be deleterious in the other. Such sexual antagonism has received a great deal of theoretical and empirical attention, almost all of which has focused on diploids. However, a sizeable minority of animals display an alternative haplodiploid mode of inheritance, encompassing both arrhenotoky, whereby males develop from unfertilized eggs, and paternal genome elimination (PGE), whereby males receive but do not transmit a paternal genome. Alongside unusual genetics, haplodiploids often exhibit social ecologies that modulate the relative value of females and males. Here, we develop a series of evolutionary-genetic models of sexual antagonism for haplodiploids, incorporating details of their molecular biology and social ecology. We find that: (1) PGE promotes female-beneficial alleles more than arrhenotoky, and to an extent determined by the timing of elimination-and degree of silencing of-the paternal genome; (2) sib-mating relatively promotes female-beneficial alleles, as do other forms of inbreeding including limited male-dispersal, oedipal-mating, and the pseudo-hermaphroditism of Icerya purchasi; (3) resource competition between related females inhibits the invasion of female-beneficial alleles; and (4) sexual antagonism foments conflicts between parents and offspring, endosymbionts and hosts, and maternal- and paternal-origin genes.


Asunto(s)
Diploidia , Endogamia , Alelos , Animales , Evolución Biológica , Femenino , Patrón de Herencia , Masculino
9.
Proc Biol Sci ; 288(1965): 20212237, 2021 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-34933602

RESUMEN

Recent years have seen an explosion of theoretical and empirical interest in the role that kin selection plays in shaping patterns of sexual conflict, with a particular focus on male harming traits. However, this work has focused solely on autosomal genes, and as such it remains unclear how demography modulates the evolution of male harm loci occurring in other portions of the genome, such as sex chromosomes and cytoplasmic elements. To investigate this, we extend existing models of sexual conflict for application to these different modes of inheritance. We first analyse the general case, revealing how sex-specific relatedness, reproductive value and the intensity of local competition combine to determine the potential for male harm. We then analyse a series of demographically explicit models, to assess how dispersal, overlapping generations, reproductive skew and the mechanism of population regulation affect sexual conflict across the genome, and drive conflict between nuclear and cytoplasmic genes. We then explore the effects of sex biases in these demographic parameters, showing how they may drive further conflicts between autosomes and sex chromosomes. Finally, we outline how different crossing schemes may be used to identify signatures of these intragenomic conflicts.


Asunto(s)
Genoma , Cromosomas Sexuales , Evolución Biológica , Demografía , Femenino , Humanos , Patrón de Herencia , Masculino , Reproducción
10.
Proc Biol Sci ; 288(1947): 20210355, 2021 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-33757350

RESUMEN

Recent theory has suggested that dosage compensation mediates sexual antagonism over X-linked genes. This process relies on the assumption that dosage compensation scales phenotypic effects between the sexes, which is largely untested. We evaluated this by quantifying transcriptome variation associated with a recently arisen, male-beneficial, X-linked mutation across tissues of the field cricket Teleogryllus oceanicus, and testing the relationship between the completeness of dosage compensation and female phenotypic effects at the level of gene expression. Dosage compensation in T. oceanicus was variable across tissues but usually incomplete, such that relative expression of X-linked genes was typically greater in females. Supporting the assumption that dosage compensation scales phenotypic effects between the sexes, we found tissues with incomplete dosage compensation tended to show female-skewed effects of the X-linked allele. In gonads, where expression of X-linked genes was most strongly female-biased, ovaries-limited genes were much more likely to be X-linked than were testes-limited genes, supporting the view that incomplete dosage compensation favours feminization of the X. Our results support the expectation that sex chromosome dosage compensation scales phenotypic effects of X-linked genes between sexes, substantiating a key assumption underlying the theoretical role of dosage compensation in determining the dynamics of sexual antagonism on the X.


Asunto(s)
Compensación de Dosificación (Genética) , Genes Ligados a X , Femenino , Masculino , Mutación , Cromosomas Sexuales , Transcriptoma
11.
Aesthet Surg J ; 41(11): NP1603-NP1618, 2021 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-33656167

RESUMEN

BACKGROUND: Although ablative techniques are the standard of care for the treatment of fine lines and wrinkles, microneedling offers a minimally invasive alternative. OBJECTIVES: The purpose of this study was to assess the efficacy of microneedling on facial and neck fine lines and wrinkles. METHODS: Thirty-five subjects between 44 and 65 years old with Fitzpatrick skin types I to IV received 4 monthly microneedling treatments over the face and neck. Subjects returned 1 and 3 months posttreatment. At every visit, high-resolution ultrasonography and optical coherence tomography were performed, and transepidermal water loss and skin elasticity were measured. Microbiopsies (0.33 mm) were collected pretreatment, before the fourth treatment and 3 months posttreatment. RESULTS: Thirty-two subjects (30 females, 2 males) completed all 7 visits. Facial dermal and epidermal density increased 101.86% and 19.28%, respectively, from baseline at 3 months posttreatment. Facial elasticity increased 28.2% from baseline at 3 months posttreatment. Facial attenuation coefficient increased 15.65% and 17.33% at 1 and 3 months posttreatment, respectively. At study completion, blood flow at a depth of 300 µm decreased 25.8% in the face and 42.3% in the neck. Relative collagen type III and elastin gene expression was statistically higher 3 months posttreatment. However, total elastin protein levels were unchanged from baseline values. Dermal muscle formation was observed in 58% of biopsies extracted 3 months posttreatment compared with 15.3% at baseline. CONCLUSIONS: The results illustrate the effects of microneedling treatments. Noninvasive measurements and biopsy data showed changes in skin architecture and collagen/elastin gene expression, suggesting skin rejuvenation, with new extracellular matrix production and muscle formation.


Asunto(s)
Técnicas Cosméticas , Envejecimiento de la Piel , Adulto , Anciano , Técnicas Cosméticas/efectos adversos , Cara/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Rejuvenecimiento , Piel
12.
Proc Biol Sci ; 287(1932): 20201633, 2020 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-32781951

RESUMEN

Females and males may face different selection pressures. Accordingly, alleles that confer a benefit for one sex often incur a cost for the other. Classic evolutionary theory holds that the X chromosome, whose sex-biased transmission sees it spending more time in females, should value females more than males, whereas autosomes, whose transmission is unbiased, should value both sexes equally. However, recent mathematical and empirical studies indicate that male-beneficial alleles may be more favoured by the X chromosome than by autosomes. Here we develop a gene's-eye-view approach that reconciles the classic view with these recent discordant results, by separating a gene's valuation of female versus male fitness from its ability to induce fitness effects in either sex. We use this framework to generate new comparative predictions for sexually antagonistic evolution in relation to dosage compensation, sex-specific mortality and assortative mating, revealing how molecular mechanisms, ecology and demography drive variation in masculinization versus feminization across the genome.


Asunto(s)
Selección Genética , Caracteres Sexuales , Alelos , Animales , Evolución Biológica , Compensación de Dosificación (Genética) , Femenino , Masculino , Reproducción , Sexo , Cromosoma X
13.
Bioessays ; 41(6): e1800212, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31132171

RESUMEN

Humans spend large portions of their time and energy talking to one another, yet it remains unclear whether this activity is primarily selfish or altruistic. Here, it is shown how parent-of-origin specific gene expression-or "genomic imprinting"-may provide an answer to this question. First, it is shown why, regarding language, only altruistic or selfish scenarios are expected. Second, it is pointed out that an individual's maternal-origin and paternal-origin genes may have different evolutionary interests regarding investment into language, and that this intragenomic conflict may drive genomic imprinting which-as the direction of imprint depends upon whether investment into language is relatively selfish or altruistic-may be used to discriminate between these two possibilities. Third, predictions concerning the impact of various mutations and epimutations at imprinted loci on language pathologies are derived. In doing so, a framework is developed that highlights avenues for using intragenomic conflicts to investigate the evolutionary drivers of language.


Asunto(s)
Evolución Biológica , Impresión Genómica/genética , Lenguaje , Adaptación Fisiológica/genética , Altruismo , Ética , Sitios Genéticos , Humanos , Relaciones Interpersonales , Modelos Genéticos , Modelos Teóricos , Fenotipo
14.
NPJ Syst Biol Appl ; 4: 36, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30210806

RESUMEN

The plant shoot apical meristem holds a stem cell niche from which all aerial organs originate. Using a computational approach we show that a mixture of monomers and heterodimers of the transcription factors WUSCHEL and HAIRY MERISTEM is sufficient to pattern the stem cell niche, and predict that immobile heterodimers form a regulatory "pocket" surrounding the stem cells. The model achieves to reproduce an array of perturbations, including mutants and tissue size modifications. We also show its ability to reproduce the recently observed dynamical shift of the stem cell niche during the development of an axillary meristem. The work integrates recent experimental results to answer the longstanding question of how the asymmetry of expression between the stem cell marker CLAVATA3 and its activator WUSCHEL is achieved, and recent findings of plasticity in the system.

15.
J Cosmet Dermatol ; 13(4): 329-35, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25399626

RESUMEN

The Safety of Microfocused Ultrasound with Visualization (MFU-V) has been well established in both controlled clinical studies and in clinical use, showing only mild and transient anticipated side effects and only rare unanticipated adverse events (AEs). This publication discusses the safety profile of MFU-V based on data from a variety of sources. Reports of side effects and AEs were obtained from published peer-reviewed medical literature, clinical studies, in-market use reports (AEs reported to the manufacturer), and retrospective chart reviews of patient treatments. Events that were typical included tenderness, redness, and slight edema. Rare events included bruising, welting, and nerve-related effects (paresthesia and paresis). Rare incidence of surface thermal effects was seen in some cases where improper technique was used. In all cases where the device was uses properly, the safety events reported tended to be transient, mild in nature, and resolved without sequelae. In general, unexpected and rare AEs could be attributed to incorrect treatment technique or classified as unrelated to MFU-V treatment. Side effects that do occur are generally mild and transient in nature. MFU-V consistently allows for safe treatment when correct treatment technique is used.


Asunto(s)
Envejecimiento de la Piel , Terapia por Ultrasonido/efectos adversos , Anestésicos Locales/administración & dosificación , Ensayos Clínicos como Asunto , Contusiones/etiología , Edema/etiología , Eritema/etiología , Humanos , Lidocaína/administración & dosificación , Vigilancia de Productos Comercializados , Literatura de Revisión como Asunto
16.
Clin Plast Surg ; 39(4): 399-408, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23036290

RESUMEN

Energy-based noninvasive surgical tools can be used for ablative bio-stimulation (eg, collagen production) or tissue restructuring functions (eg, tightening or lifting) and are the subject of this review. The authors present the various methods and tools for noninvasive cosmetic surgery (ultrasound, radiofrequency, cryolipolysis, and lasers) and present the clinical outcomes of each. They summarize techniques and methods and their indications, physical parameters and tissue target, and consistency.


Asunto(s)
Técnicas Cosméticas , Técnicas de Ablación , Humanos , Lipectomía/métodos , Terapia por Luz de Baja Intensidad , Terapia por Radiofrecuencia , Envejecimiento de la Piel , Grasa Subcutánea , Terapia por Ultrasonido/métodos
17.
J Hand Surg Am ; 36(5): 795-7, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21527136

RESUMEN

We present the case of a young woman who sustained a stab injury to the left palm with a kitchen knife that entered the thenar eminence and exited dorsally between the index and middle metacarpals. We repaired the injured motor branch of the ulnar nerve using a dorsal approach and a proximal osteotomy of the index metacarpal.


Asunto(s)
Traumatismos de la Mano/cirugía , Procedimientos de Cirugía Plástica/métodos , Nervio Cubital/cirugía , Femenino , Estudios de Seguimiento , Traumatismos de la Mano/diagnóstico , Humanos , Puntaje de Gravedad del Traumatismo , Microcirugia/métodos , Neuronas Motoras/patología , Recuperación de la Función , Medición de Riesgo , Resultado del Tratamiento , Nervio Cubital/lesiones , Heridas Penetrantes/diagnóstico , Heridas Penetrantes/cirugía , Adulto Joven
18.
Free Radic Biol Med ; 49(5): 872-80, 2010 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-20550962

RESUMEN

Living organisms are exposed to nitrosative stress mediated by nitric oxide (NO) and its derivatives. Multiple cellular mechanisms may be needed to cope with nitrosative stress. This work takes advantage of a hypersensitive Escherichia coli genetic system to identify genes involved in resistance to nitrosative stress in mouse lungs. Mouse thioredoxin domain-containing 5 (mTrx 5) was identified as one of the candidate genes. Its ability to complement the hypersensitive phenotype in an E. coli mutant strain was confirmed by genetic analysis. Purified recombinant mouse thioredoxin domain-containing 5 protein reduced DNA damage that is sensitive to cleavage by the deamination repair enzyme endonuclease V, indicating that mTrx 5 may play a role in scavenging the reactive nitrogen species. E. coli thioredoxin 1 and thioredoxin 2 proteins also reduced the DNA damage in a similar manner. Deletion of trxA (encodes thioredoxin 1) or trxC (encodes thioredoxin 2) in E. coli resulted in a slightly higher sensitivity to nitrosative stress. On the other hand, deletion of both trxA and trxC greatly increased its sensitivity to nitrosative stress. Complementation with the mTrx 5 gene rescued the sensitive phenotype of the double deletion mutant. The potential roles that mTrx 5 may play in coping with nitrosative stress are discussed.


Asunto(s)
Resistencia a Medicamentos/genética , Estrés Oxidativo/genética , Especies de Nitrógeno Reactivo/farmacología , Tiorredoxinas/fisiología , Animales , Células Cultivadas , Clonación Molecular , Citoprotección/genética , Daño del ADN/efectos de los fármacos , Daño del ADN/genética , Escherichia coli/genética , Biblioteca de Genes , Pulmón/química , Pulmón/metabolismo , Ratones , Pruebas de Sensibilidad Microbiana , Estrés Oxidativo/efectos de los fármacos , Tiorredoxinas/genética , Tiorredoxinas/metabolismo , Transformación Genética
19.
Cell Transplant ; 19(1): 79-87, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-19878625

RESUMEN

While advances in regenerative medicine and vascular tissue engineering have been substantial in recent years, important stumbling blocks remain. In particular, the limited life span of differentiated cells that are harvested from elderly human donors is an important limitation in many areas of regenerative medicine. Recently, a mutant of the human telomerase reverse transcriptase enzyme (TERT) was described, which is highly processive and elongates telomeres more rapidly than conventional telomerase. This mutant, called pot1-TERT, is a chimeric fusion between the DNA binding protein pot1 and TERT. Because pot1-TERT is highly processive, it is possible that transient delivery of this transgene to cells that are utilized in regenerative medicine applications may elongate telomeres and extend cellular life span while avoiding risks that are associated with retroviral or lentiviral vectors. In the present study, adenoviral delivery of pot1-TERT resulted in transient reconstitution of telomerase activity in human smooth muscle cells, as demonstrated by telomeric repeat amplification protocol (TRAP). In addition, human engineered vessels that were cultured using pot1-TERT-expressing cells had greater collagen content and somewhat better performance in vivo than control grafts. Hence, transient delivery of pot1-TERT to elderly human cells may be useful for increasing cellular life span and improving the functional characteristics of resultant tissue-engineered constructs.


Asunto(s)
Vasos Sanguíneos/trasplante , Proteínas Recombinantes de Fusión/uso terapéutico , Telomerasa/uso terapéutico , Proteínas de Unión a Telómeros/uso terapéutico , Ingeniería de Tejidos/métodos , Transfección/métodos , Adenoviridae/genética , Adulto , Animales , Reactores Biológicos/normas , Vasos Sanguíneos/citología , Técnicas de Cultivo de Célula , Células Cultivadas , Senescencia Celular/genética , Colágeno/metabolismo , Vectores Genéticos/uso terapéutico , Supervivencia de Injerto/genética , Humanos , Masculino , Músculo Liso Vascular/citología , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/trasplante , Ratas , Ratas Desnudas , Proteínas Recombinantes de Fusión/genética , Complejo Shelterina , Telomerasa/genética , Proteínas de Unión a Telómeros/genética
20.
Ann N Y Acad Sci ; 1131: 44-9, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18519958

RESUMEN

In the last 5 years major advances have been made in the field of tissue engineering. However, while engineering of tissues from nearly every major system in the body have been studied and improved, little has been done with the engineering of viable lymphatic tissues. Recent advances in understanding of lymphatic biology have allowed the easy isolation of pure lymphatic cell cultures, increasing, in turn, the ability to study lymphatic biology in greater detail. This has allowed the elucidation of lymphatic properties on the structural, cellular, and molecular levels, making possible the successful development of the first lymphatic engineered tissues. Among such advances are the engineering of lymphatic capillaries, the development of a functioning bioreactor designed to culture lymph nodes in vitro, and in vivo growth of lymphatic organoids. However, there has been no research on the engineering of functional lymphangions. While the advances made in the study of lymphatic biology are encouraging, the complexities of the system make the engineering of certain functional lymphatic tissues somewhat more difficult.


Asunto(s)
Tejido Linfoide/fisiología , Ingeniería de Tejidos/métodos , Animales , Reactores Biológicos , Células Cultivadas , Endotelio Vascular/citología , Humanos , Vasos Linfáticos/citología , Tejido Linfoide/citología , Ratones , Ratones SCID , Ingeniería de Tejidos/tendencias
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