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1.
Exerc Sport Sci Rev ; 52(2): 63-67, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38391187

RESUMO

Of the "Yamanaka factors" Oct3/4 , Sox2 , Klf4 , and c-Myc (OSKM), the transcription factor c-Myc ( Myc ) is the most responsive to exercise in skeletal muscle and is enriched within the muscle fiber. We hypothesize that the pulsatile induction of MYC protein after bouts of exercise can serve to epigenetically reprogram skeletal muscle toward a more resilient and functional state.


Assuntos
Reprogramação Celular , Epigênese Genética , Humanos , Músculo Esquelético
2.
Acta Obstet Gynecol Scand ; 103(6): 1175-1182, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38383115

RESUMO

INTRODUCTION: Differentiated vulvar intraepithelial neoplasia (dVIN) is a high-risk preinvasive vulvar lesion and precursor of human papillomavirus-independent vulvar squamous cell carcinoma (VSCC). Due to its rarity, literature data on its malignant potential are scant. The aim of the study is to assess the risk of developing VSCC in patients surgically treated for dVIN not associated with VSCC (solitary dVIN) and the risk of VSCC recurrence in patients treated for dVIN associated with VSCC (dVIN-VSCC) at first diagnosis. MATERIAL AND METHODS: A historical cohort study was performed in a northern Italy referral center for vulvar neoplasms. All consecutive women surgically treated for histologically confirmed dVIN from 1994 to 2021 were collected. Primary outcome was cancer risk or recurrent cancer risk, secondary outcomes were risk factors associated with VSCC development or recurrence. Kaplan-Meier method and log-rank test were used to estimate cancer risk or recurrent cancer risk differences and uni- and multivariate Cox regression analyses to identify risk factors associated with VSCC development in solitary dVIN and recurrence of dVIN-VSCC. RESULTS: Seventy-six patients with dVIN at preoperative biopsy were included: at excisional specimens 44 were solitary dVIN and 32 were dVIN-VSCC. The absolute risk of VSCC development after solitary dVIN treatment was 43.2% with median time to to VSCC diagnosis of 25.4 months (range 3.5-128.0 months). VSCC recurrence absolute risk in treated dVIN-VSCC patients was 31.3% with median time to VSCC recurrence of 52.9 months (range 6.5-94.8 months). At uni- and multivariate regression analyses, only compliant topical ultrapotent corticosteroid treatment after solitary dVIN excision showed an ability to prevent VSCC development. No protective effect by corticosteroid treatment was shown for VSCC recurrence in dVIN-VSCC patients. Smoking was associated with higher cancer recurrence risk in dVIN-VSCC patients on both uni- and multivariate regression analyses. CONCLUSIONS: Patients with dVIN have a high risk of developing both primary and recurring VSCC. Early recognition, long-term follow up, and compliant ultrapotent topical corticosteroid treatment are recommended.


Assuntos
Carcinoma in Situ , Carcinoma de Células Escamosas , Recidiva Local de Neoplasia , Neoplasias Vulvares , Humanos , Feminino , Neoplasias Vulvares/patologia , Carcinoma in Situ/patologia , Carcinoma in Situ/terapia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/epidemiologia , Carcinoma de Células Escamosas/patologia , Prognóstico , Seguimentos , Estudos de Coortes , Adulto , Fatores de Risco , Idoso , Itália/epidemiologia
3.
J Physiol ; 601(4): 763-782, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36533424

RESUMO

Exercise promotes functional improvements in aged tissues, but the extent to which it simulates partial molecular reprogramming is unknown. Using transcriptome profiling from (1) a skeletal muscle-specific in vivo Oct3/4, Klf4, Sox2 and Myc (OKSM) reprogramming-factor expression murine model; (2) an in vivo inducible muscle-specific Myc induction murine model; (3) a translatable high-volume hypertrophic exercise training approach in aged mice; and (4) human exercise muscle biopsies, we collectively defined exercise-induced genes that are common to partial reprogramming. Late-life exercise training lowered murine DNA methylation age according to several contemporary muscle-specific clocks. A comparison of the murine soleus transcriptome after late-life exercise training to the soleus transcriptome after OKSM induction revealed an overlapping signature that included higher JunB and Sun1. Also, within this signature, downregulation of specific mitochondrial and muscle-enriched genes was conserved in skeletal muscle of long-term exercise-trained humans; among these was muscle-specific Abra/Stars. Myc is the OKSM factor most induced by exercise in muscle and was elevated following exercise training in aged mice. A pulse of MYC rewired the global soleus muscle methylome, and the transcriptome after a MYC pulse partially recapitulated OKSM induction. A common signature also emerged in the murine MYC-controlled and exercise adaptation transcriptomes, including lower muscle-specific Melusin and reactive oxygen species-associated Romo1. With Myc, OKSM and exercise training in mice, as well habitual exercise in humans, the complex I accessory subunit Ndufb11 was lower; low Ndufb11 is linked to longevity in rodents. Collectively, exercise shares similarities with genetic in vivo partial reprogramming. KEY POINTS: Advances in the last decade related to cellular epigenetic reprogramming (e.g. DNA methylome remodelling) toward a pluripotent state via the Yamanaka transcription factors Oct3/4, Klf4, Sox2 and Myc (OKSM) provide a window into potential mechanisms for combatting the deleterious effects of cellular ageing. Using global gene expression analysis, we compared the effects of in vivo OKSM-mediated partial reprogramming in skeletal muscle fibres of mice to the effects of late-life murine exercise training in muscle. Myc is the Yamanaka factor most induced by exercise in skeletal muscle, and so we compared the MYC-controlled transcriptome in muscle to Yamanaka factor-mediated and exercise adaptation mRNA landscapes in mice and humans. A single pulse of MYC is sufficient to remodel the muscle methylome. We identify partial reprogramming-associated genes that are innately altered by exercise training and conserved in humans, and propose that MYC contributes to some of these responses.


Assuntos
Envelhecimento , Reprogramação Celular , Exercício Físico , Músculo Esquelético , Animais , Humanos , Camundongos , Reprogramação Celular/genética , Modelos Animais de Doenças , Metilação de DNA , Exercício Físico/fisiologia , Perfilação da Expressão Gênica , Proteínas de Membrana/metabolismo , Proteínas Mitocondriais/metabolismo , Músculo Esquelético/metabolismo , Envelhecimento/genética , Envelhecimento/fisiologia
4.
BMC Genomics ; 24(1): 374, 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37403010

RESUMO

BACKGROUND: Cancer-cachexia (CC) is a debilitating condition affecting up to 80% of cancer patients and contributing to 40% of cancer-related deaths. While evidence suggests biological sex differences in the development of CC, assessments of the female transcriptome in CC are lacking, and direct comparisons between sexes are scarce. This study aimed to define the time course of Lewis lung carcinoma (LLC)-induced CC in females using transcriptomics, while directly comparing biological sex differences. RESULTS: We found the global gene expression of the gastrocnemius muscle of female mice revealed biphasic transcriptomic alterations, with one at 1 week following tumor allograft and another during the later stages of cachexia development. The early phase was associated with the upregulation of extracellular-matrix pathways, while the later phase was characterized by the downregulation of oxidative phosphorylation, electron transport chain, and TCA cycle. When DEGs were compared to a known list of mitochondrial genes (MitoCarta), ~ 47% of these genes were differently expressed in females exhibiting global cachexia, suggesting transcriptional changes to mitochondrial gene expression happens concomitantly to functional impairments previously published. In contrast, the JAK-STAT pathway was upregulated in both the early and late stages of CC. Additionally, we observed a consistent downregulation of Type-II Interferon signaling genes in females, which was associated with protection in skeletal muscle atrophy despite systemic cachexia. Upregulation of Interferon signaling was noted in the gastrocnemius muscle of cachectic and atrophic male mice. Comparison of female tumor-bearing mice with males revealed ~ 70% of DEGs were distinct between sexes in cachectic animals, demonstrating dimorphic mechanisms of CC. CONCLUSION: Our findings suggest biphasic disruptions in the transcriptome of female LLC tumor-bearing mice: an early phase associated with ECM remodeling and a late phase, accompanied by the onset of systemic cachexia, affecting overall muscle energy metabolism. Notably, ~ 2/3 of DEGs in CC are biologically sex-specific, providing evidence of dimorphic mechanisms of cachexia between sexes. Downregulation of Type-II Interferon signaling genes appears specific to CC development in females, suggesting a new biological sex-specific marker of CC not reliant on the loss of muscle mass, that might represent a protective mechanism against muscle loss in CC in female mice.


Assuntos
Caquexia , Carcinoma Pulmonar de Lewis , Feminino , Masculino , Camundongos , Animais , Caquexia/genética , Caquexia/metabolismo , Caquexia/patologia , Janus Quinases/metabolismo , Transdução de Sinais , Fatores de Transcrição STAT/metabolismo , Músculo Esquelético/metabolismo , Atrofia Muscular/metabolismo , Atrofia Muscular/patologia , Carcinoma Pulmonar de Lewis/complicações , Carcinoma Pulmonar de Lewis/metabolismo , Carcinoma Pulmonar de Lewis/patologia , Transcriptoma , Interferons/metabolismo
5.
Langmuir ; 38(4): 1334-1347, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35051338

RESUMO

Perfume mixtures contain perfume raw materials (PRMs) with varying structures and hydrophobicities, which influence PRM localization within a surfactant-based formulation and thereby affect the phase behavior. In rinse-off products, the addition of water can further affect the phase behavior. In this study, a mixture of 12 PRMs was used as the oil phase in an aqueous system consisting of sodium trideceth-2 sulfate as a primary surfactant, cocamidopropyl betaine as a cosurfactant, and dipropylene glycol as a cosolvent. A series of phase diagrams were constructed with increasing water content, simulating the use conditions for rinse-off products, to determine how the phase boundaries shift with dilution. Using these phase diagrams, the compositions of interest in the micelle without perfume, micelle with perfume, microemulsion, and micelle-microemulsion transition regions were identified at each dilution level. The structural changes were probed through combined small-angle neutron scattering (SANS) and cryo-transmission electron microscopy analyses. The SANS results showed that ellipsoidal micelles were maintained as the perfume content and the dilution level increased. With ≥50 wt % water, increasing the perfume content increased the micelle volume. Interestingly, a higher rate of volume increase was observed at ≥70 wt % water. Notably, the volumes of the micelles with and without perfume increased steadily with dilution, whereas the volumes of the assemblies in the transition region and the microemulsion region increased more rapidly once diluted to 70 and 80 wt % water, respectively.

6.
Int J Gynecol Cancer ; 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35914776

RESUMO

OBJECTIVES: We report the disease-specific survival of patients with human papillomavirus (HPV)-associated and HPV-independent vulvar squamous cell carcinomas and determine whether differences exist and are independent of stage and age at diagnosis. METHODS: This was a retrospective cohort study with case note and pathology slide review of 265 consecutive women with vulvar squamous cell carcinoma. These patients were treated over a 15 year period (2001-2016) at a centralized cancer center covering half the population of New Zealand. The women's cancers were categorized dependent on their adjacent pathology, immunohistochemistry and HPV status following expert slide review. Disease-specific survival was calculated using Kaplan-Meier univariable and Cox proportional hazard (adjusting for stage, age, and HPV dependence) multivariable methods. RESULTS: The survival analysis included 236 women with follow-up to 96 months; 124 of them were HPV-associated, 95 HPV-independent, and 17 were unclassifiable. Of the 236 women, 146 were stage 1 (92 HPV-associated, 49 HPV-independent, 5 unclassifiable), 13 stage II (7 HPV-associated, 6 HPV-independent), 62 stage III (20 HPV-associated, 34 HPV-independent, 8 unclassifiable) and 15 stage IV (5 HPV-associated, 6 HPV-independent, 4 unclassifiable). HPV-independent vulvar squamous cell carcinomas had significantly worse survival than HPV-associated vulvar squamous cell carcinomas independent of stage and age at diagnosis (HR 3.6 (95% confidence interval (CI): 1.6 to 8.2)). Tumors that were unclassifiable by HPV type also had significantly worse survival than HPV-associated tumors independent of stage and age at diagnosis (HR 6.2 (95% CI: 2.4 to 16.0)). CONCLUSIONS: HPV-independent vulvar squamous cell carcinomas present more frequently in older women than HPV-associated tumors. However, the poorer prognosis is independent of age and stage, with worse outcomes even in early stage disease.

7.
Breast J ; 2022: 3342910, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35711884

RESUMO

The surgical treatment of breast cancer has rapidly evolved over the past 50 years, progressing from Halsted's radical mastectomy to a public campaign of surgical options, aesthetic reconstruction, and patient empowerment. Sparked by the research of Dr. Bernard Fisher and the first National Surgical Adjuvant Breast and Bowel Project trial in 1971, the field of breast surgery underwent significant growth over the next several decades, enabling general surgeons to limit their practices to the breast. High surgical volumes eventually led to the development of the first formal breast surgical oncology fellowship in a large community-based hospital at Baylor University Medical Center in 1982. The establishment of the American Society of Breast Surgeons, as well as several landmark clinical trials and public campaign efforts, further contributed to the advancement of breast surgery. In 2003, the Society of Surgical Oncology (SSO), in partnership with the American Society of Breast Surgeons and the American Society of Breast Disease, approved its first fellowship training program in breast surgical oncology. Since that time, the number of American fellowship programs has increased to approximately 60 programs, focusing not only on training in breast surgery, but also in medical oncology, radiation oncology, pathology, breast imaging, and plastic and reconstructive surgery. This article focuses on the happenings in the United States that led to the transition of breast surgery from a subset of general surgery to its own specialized field.


Assuntos
Neoplasias da Mama , Oncologia Cirúrgica , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Bolsas de Estudo , Feminino , Humanos , Mastectomia/métodos , Oncologia , Oncologia Cirúrgica/educação , Estados Unidos
8.
J Low Genit Tract Dis ; 26(4): 323-327, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35930419

RESUMO

OBJECTIVE: The human papillomavirus (HPV) vaccine, introduced in New Zealand (NZ) in 2008, is predicted to substantially lower the incidence of HPV-associated precancers and cancers. The aim of this study is to estimate the proportion of vulvar intraepithelial neoplasia (VIN) lesions and invasive vulvar squamous cell carcinomas (SCCV) attributable to HPV in NZ women treated by the Auckland Regional Gynecological Oncology Service, covering an estimated 50% of the NZ population. MATERIALS AND METHODS: Polymerase chain reaction and reverse hybridization were used to analyze retrospective histologically proven SCCV from 1990 to 2007 and VIN lesions from 2000 to 2007 for HPV content and genotype in a collaborative study with the Catalan Institute of Oncology. Immunohistochemistry for p16INK4a was performed on SCCV, which were attributed to HPV if both tested positive. RESULTS: Polymerase chain reaction testing for HPV content and genotype was performed on 66 VIN lesions (all high-grade squamous intraepithelial lesions) and 189 SCCV. In addition, p16 immunohistochemistry was performed on 168 of the 189 SCCV (88.9%) tested for HPV-DNA. Overall, 61 SCCV cases (36.3%) were attributed to HPV (HPV+/p16+), and 89 SCCV cases (53%) were considered to have developed independently of HPV (HPV-/p16-). Known high-risk HPV genotypes were present in 96.8% of HPV-DNA-positive vulvar high-grade squamous intraepithelial lesions and 98.4% of HPV-attributable SCCV. Human papillomavirus 16 represented the most common genotype in both. CONCLUSIONS: Overall, the HPV vaccine is likely to substantially alter the profile of SCCV in our region. The results provide a baseline assessment of the HPV status of vulvar neoplasia before the introduction of the HPV vaccine.


Assuntos
Alphapapillomavirus , Carcinoma in Situ , Carcinoma de Células Escamosas , Infecções por Papillomavirus , Vacinas contra Papillomavirus , Lesões Intraepiteliais Escamosas , Neoplasias Vulvares , Carcinoma in Situ/epidemiologia , Carcinoma in Situ/patologia , Carcinoma de Células Escamosas/patologia , DNA Viral/genética , Feminino , Humanos , Nova Zelândia/epidemiologia , Papillomaviridae/genética , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/patologia , Estudos Retrospectivos , Vulva/patologia , Neoplasias Vulvares/patologia
9.
J Chem Phys ; 155(7): 074901, 2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34418934

RESUMO

We systematically investigate model synthetic and natural bottlebrush polyelectrolyte solutions through an array of experimental techniques (osmometry and neutron and dynamic light scattering) along with molecular dynamics simulations to characterize and contrast their structures over a wide range of spatial and time scales. In particular, we perform measurements on solutions of aggrecan and the synthetic bottlebrush polymer, poly(sodium acrylate), and simulations of solutions of highly coarse-grained charged bottlebrush molecules having different degrees of side-branch density and inclusion of an explicit solvent and ion hydration effects. While both systems exhibit a general tendency toward supramolecular organization in solution, bottlebrush poly(sodium acrylate) solutions exhibit a distinctive "polyelectrolyte peak" in their structure factor, but no such peak is observed in aggrecan solutions. This qualitative difference in scattering properties, and thus polyelectrolyte solution organization, is attributed to a concerted effect of the bottlebrush polymer topology and the solvation of the polymer backbone and counterions. The coupling of the polyelectrolyte topological structure with the counterion distribution about the charged polymer molecules along with direct polymer segmental hydration makes their solution organization and properties "tunable," a phenomenon that has significant ramifications for biological function and disease as well as for numerous materials applications.

10.
Artigo em Inglês | MEDLINE | ID: mdl-32094137

RESUMO

Plazomicin was active against 97.0% of 8,783 Enterobacterales isolates collected in the United States (2016 and 2017), and only 6 isolates carried 16S rRNA methyltransferases conferring resistance to virtually all aminoglycosides. Plazomicin (89.2% to 95.9% susceptible) displayed greater activity than amikacin (72.5% to 78.6%), gentamicin (30.4% to 45.9%), and tobramycin (7.8% to 22.4%) against carbapenem-resistant and extensively drug-resistant isolates. The discrepancies among the susceptibility rates for these agents was greater when applying breakpoints generated using the same stringent contemporary methods applied to determine plazomicin breakpoints.


Assuntos
Aminoglicosídeos/farmacologia , Antibacterianos/uso terapêutico , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Infecções por Enterobacteriaceae/microbiologia , Enterobacteriaceae/efeitos dos fármacos , Sisomicina/análogos & derivados , Farmacorresistência Bacteriana/genética , Enterobacteriaceae/genética , Hospitais , Humanos , Testes de Sensibilidade Microbiana , RNA Ribossômico 16S/genética , Sisomicina/farmacologia , Estados Unidos
11.
Artigo em Inglês | MEDLINE | ID: mdl-31767718

RESUMO

The polymyxins are important agents for carbapenem-resistant Gram-negative bacilli. The United States Committee on Antimicrobial Susceptibility Testing breakpoint recommendations for colistin and polymyxin B are that isolates of Pseudomonas aeruginosa, Acinetobacter baumannii, and Enterobacteriaceae are considered susceptible at MIC values of ≤2 mg/liter. These recommendations are contingent upon dosing and testing strategies that are described in this commentary. Importantly, these recommendations are not applicable to lower respiratory tract infections, for which we recommend no breakpoints. Furthermore, there is no breakpoint recommendation for polymyxin B for lower urinary tract infections.


Assuntos
Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana/normas , Polimixinas/farmacologia , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Colistina/farmacologia , Guias como Assunto , Humanos , Polimixina B/farmacologia , Polimixinas/administração & dosagem , Polimixinas/uso terapêutico , Infecções Respiratórias/microbiologia , Estados Unidos , Infecções Urinárias/microbiologia
12.
Gynecol Oncol ; 157(2): 450-455, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32037194

RESUMO

OBJECTIVE: To investigate the incidence and survival of Vulvar Squamous Cell Carcinoma (VSCC) by etiology over a 27 year period. METHOD: Retrospective case-note and pathology slide review of 390 consecutive VSCC, treated at a Centralized Cancer Centre covering half New Zealand's population, 1990-2016. Incidence was calculated in 5-6 year cohorts and correlated with precursor of the VSCC, age and stage. RESULTS: Age-standardized incidence of all VSCC did not change significantly, however age standardized incidence of HPV-dependent VSCC increased significantly, from 0.55/100,000 (95% CI 0.38-0.72) in 1991-2000 to 0.83/100,000 (95% CI 0.68-0.97) in 2001-2016, with a significant decrease in the incidence of HPV-independent VSCC, from 0.76/100,000 (95% CI 0.58-0.95) to 0.54/100,000 (95%CI 0.43-0.65). HPV-dependent VSCC in women ≥50 years increased significantly from 0.75/100,000 (95% CI 0.45-1.17) to 1.43/100,000 (95% CI 1.14-1.77), with no significant change seen in younger women. HPV-independent VSCC in women ≥50 years has decreased significantly from 2.53/100,000 (95% CI 1.95-3.23) to 1.62/100,000 (95% CI 1.31-1.98) with no change in younger women. The proportion of HPV-dependent VSCC has increased from 25% to 50%. Age standardized death rate from VSCC has not changed significantly from 0.22/100,000 (95% CI 0.10-0.34) in 2001-5 to 0.27/100,000 (95% CI 0.15-0.40) in 2011-16. Five year survival for HPV-dependent VSCC was 93% and 68% for HPV-independent VSCC (p < .0001). CONCLUSIONS: HPV-dependent VSCC incidence has increased significantly and now accounts for half of VSCC, with a significant rise in women over 50. HPV-dependent and independent VSCC have different prognoses and should be registered and investigated separately.


Assuntos
Carcinoma de Células Escamosas/epidemiologia , Infecções por Papillomavirus/epidemiologia , Neoplasias Vulvares/epidemiologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/virologia , Estudos de Coortes , Feminino , Humanos , Incidência , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Nova Zelândia/epidemiologia , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/mortalidade , Infecções por Papillomavirus/patologia , Estudos Retrospectivos , Neoplasias Vulvares/mortalidade , Neoplasias Vulvares/patologia , Neoplasias Vulvares/virologia , Adulto Jovem
13.
Soft Matter ; 16(31): 7289-7298, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32667374

RESUMO

We report results of small angle neutron scattering measurements made on sodium polystyrene sulfonate in aqueous salt solutions. The correlation length (ξ) and osmotic compressibility are measured as a function of polymer (c) and added salt (cS) concentrations, and the results are compared with scaling predictions and the random-phase approximation (RPA). In Dobrynin et al.'s scaling model the osmotic pressure consists of a counter-ion contribution and a polymer contribution. The polymer contribution is found to be two orders of magnitude smaller than expected from the scaling model, in agreement with earlier observations made on neutral polymers in good solvent condition. RPA allows the determination of single-chain dimensions in semidilute solutions at high polymer and added salt concentrations, but fails for cS≤ 2 M. The χ parameter can be modelled as the sum of an intrinsic contribution (χ0) and an electrostatic term: χ∼χ0 + K'/√cS, where χ0 > 0.5 is consistent with the hydrophobic nature of the backbone of NaPSS. The dependence of χelec∼ 1/√cS disagrees with the random-phase approximation (χelec∼ 1/cs), but agrees with the light scattering results in dilute solution and Dobrynin et al.'s scaling treatment of electrostatic excluded volume.

14.
J Chem Phys ; 152(19): 194904, 2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-33687251

RESUMO

There is a great interest in the synthesis and characterization of polyelectrolytes that mimic naturally occurring bottlebrush polyelectrolytes to capitalize on the unique properties of this class of macromolecules. Charged bottlebrush polymers form the protective mucus layer in the lungs, stomach, and orifices of animals and provide osmotic stabilization and lubrication to joints. In the present work, we systematically investigate bottlebrush poly(sodium acrylates) through a combination of measurements of solution properties (osmometry, small-angle neutron scattering, and dynamic light scattering) and molecular dynamics simulations, where the bottlebrush properties are compared in each case to their linear polymer counterparts. These complementary experimental and computational methods probe vastly different length- and timescales, allowing for a comprehensive characterization of the supermolecular structure and dynamics of synthetic polyelectrolyte bottlebrush molecules in solution.

15.
J Low Genit Tract Dis ; 24(3): 330-331, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32501869

RESUMO

The Lower Anogenital Squamous Terminology project and subsequent publication have grouped preinvasive human papillomavirus-associated squamous intraepithelial lesions of the lower genital tract and adjacent skin as a single entity. We are concerned that as a result of this grouping, some of the clinically relevant differences may not be taken into consideration. We describe differences between high-grade squamous intraepithelial lesion of the vulva and cervix (vulvar intraepithelial neoplasia and cervical intraepithelial neoplasia), in embryology (arising from ectoderm vs mesoderm), clinical presentations (symptoms or signs due to many vulvar lesions vs abnormal cytology), examination techniques and diagnosis (clinical examination of potentially widely involved areas vs colposcopy of the transformation zone), natural history, management, and follow-up requirements (long-term clinical assessment vs cytology and human papillomavirus testing). We believe that failure to understand these important differences will lead to errors in management.


Assuntos
Lesões Intraepiteliais Escamosas/patologia , Displasia do Colo do Útero/patologia , Neoplasias do Colo do Útero/patologia , Neoplasias Vulvares/patologia , Adulto , Colo do Útero/patologia , Colposcopia , Feminino , Humanos , Pessoa de Meia-Idade , Lesões Intraepiteliais Escamosas/cirurgia , Terminologia como Assunto , Neoplasias do Colo do Útero/cirurgia , Neoplasias Vulvares/cirurgia , Adulto Jovem , Displasia do Colo do Útero/cirurgia
16.
Clin Infect Dis ; 69(1): 1-11, 2019 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-30715222

RESUMO

BACKGROUND: Infections caused by antibiotic-resistant bacteria, including carbapenem-resistant Enterobacteriaceae, have increased in frequency, resulting in significant patient morbidity and mortality. The Infectious Diseases Society of America continues to propose legislative, regulatory, and funding solutions to address this escalating crisis. This report updates the status of development and approval of systemic antibiotics in the United States as of late 2018. METHODS: We performed a review of the published literature and on-line clinical trials registry at www.clinicaltrials.gov to identify new systemically acting orally and/or intravenously administered antibiotic drug candidates in the development pipeline, as well as agents approved by the US Food and Drug Administration since 2012. RESULTS: Since our 2013 pipeline status report, the number of new antibiotics annually approved for marketing in the United States has reversed its previous decline, likely influenced by new financial incentives and increased regulatory flexibility. Although our survey demonstrates progress in development of new antibacterial drugs that target infections caused by resistant bacterial pathogens, the majority of recently approved agents have been modifications of existing chemical classes of antibiotics, rather than new chemical classes. Furthermore, larger pharmaceutical companies continue to abandon the field, and smaller companies face financial difficulties as a consequence. CONCLUSIONS: Unfortunately, if 20 × '20 is achieved due to efforts embarked upon in decades past, it could mark the apex of antibiotic drug development for years to come. Without increased regulatory, governmental, industry, and scientific support and collaboration, durable solutions to the clinical, regulatory, and economic problems posed by bacterial multidrug resistance will not be found.


Assuntos
Antibacterianos/uso terapêutico , Aprovação de Drogas/estatística & dados numéricos , United States Food and Drug Administration , Aprovação de Drogas/organização & administração , Descoberta de Drogas , Farmacorresistência Bacteriana Múltipla , Sociedades Médicas , Estados Unidos
17.
Artigo em Inglês | MEDLINE | ID: mdl-31010862

RESUMO

Bloodstream infection (BSI) organisms were consecutively collected from >200 medical centers in 45 nations between 1997 and 2016. Species identification and susceptibility testing followed Clinical and Laboratory Standards Institute broth microdilution methods at a central laboratory. Clinical data and isolates from 264,901 BSI episodes were collected. The most common pathogen overall was Staphylococcus aureus (20.7%), followed by Escherichia coli (20.5%), Klebsiella pneumoniae (7.7%), Pseudomonas aeruginosa (5.3%), and Enterococcus faecalis (5.2%). S. aureus was the most frequently isolated pathogen overall in the 1997-to-2004 period, but E. coli was the most common after 2005. Pathogen frequency varied by geographic region, hospital-onset or community-onset status, and patient age. The prevalence of S. aureus isolates resistant to oxacillin (ORSA) increased until 2005 to 2008 and then declined among hospital-onset and community-acquired BSI in all regions. The prevalence of vancomycin-resistant enterococci (VRE) was stable after 2012 (16.4% overall). Daptomycin resistance among S. aureus and enterococci (DRE) remained rare (<0.1%). In contrast, the prevalence of multidrug-resistant (MDR) Enterobacteriaceae increased from 6.2% in 1997 to 2000 to 15.8% in 2013 to 2016. MDR rates were highest among nonfermentative Gram-negative bacilli (GNB), and colistin was the only agent with predictable activity against Acinetobacter baumannii-Acinetobacter calcoaceticus complex (97% susceptible). In conclusion, S. aureus and E. coli were the predominant causes of BSI worldwide during this 20-year surveillance period. Important resistant phenotypes among Gram-positive pathogens (MRSA, VRE, or DRE) were stable or declining, whereas the prevalence of MDR-GNB increased continuously during the monitored period. MDR-GNB represent the greatest therapeutic challenge among common bacterial BSI pathogens.


Assuntos
Bacteriemia/epidemiologia , Bacteriemia/microbiologia , Infecções por Acinetobacter/epidemiologia , Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/isolamento & purificação , Antibacterianos/farmacologia , Infecções Comunitárias Adquiridas/epidemiologia , Infecções Comunitárias Adquiridas/microbiologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/isolamento & purificação , Europa (Continente)/epidemiologia , Infecções por Bactérias Gram-Positivas/epidemiologia , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Infecções por Klebsiella/epidemiologia , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/isolamento & purificação , América Latina/epidemiologia , Testes de Sensibilidade Microbiana , Infecções por Pseudomonas/epidemiologia , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/isolamento & purificação , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação
18.
Vet Anaesth Analg ; 46(4): 409-420, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31202620

RESUMO

OBJECTIVE: Attention is drawn to the potential of global warming to influence the health and wellbeing of the human race. There is increasing public and governmental pressure on healthcare organisations to mitigate and adapt to the climate changes that are occurring. The science of anaesthetic agents such as nitrous oxide and the halogenated anaesthetic agents such as greenhouse gases and ozone-depleting agents is discussed and quantified. Additional environmental impacts of healthcare systems are explored. The role of noninhalational anaesthetic pharmaceuticals is discussed, including the environmental life-cycle analyses of their manufacture, transport, disposal and use. The significant role of anaesthetists in recycling and waste management, resource use (particularly plastics, water and energy) and engagement in sustainability are discussed. Finally, future directions for sustainability in veterinary anaesthesia are proposed. CONCLUSIONS: Veterinary anaesthetists have a considerable opportunity to drive sustainability within their organisations through modification of their practice, research and education. The principles of sustainability may help veterinary anaesthetists to mitigate and adapt to our environmental crisis. Due to their particular impact as greenhouse gases, anaesthetic agents should be used conservatively with the lowest safe fresh gas flow possible. Technologies for reprocessing anaesthetic agents are described.


Assuntos
Anestesia/veterinária , Anestésicos/química , Conservação dos Recursos Naturais , Aquecimento Global , Medicina Veterinária , Animais , Meio Ambiente
19.
Artigo em Inglês | MEDLINE | ID: mdl-29038277

RESUMO

Ventilator-associated bacterial pneumonia (VABP) is a difficult therapeutic problem. Considerable controversy exists regarding the optimal chemotherapy for this entity. The recent guidelines of the Infectious Diseases Society of America and the American Thoracic Society recommend a 7-day therapeutic course for VABP based on the balance of no negative impact on all-cause mortality, less resistance emergence, and fewer antibiotic treatment days, counterbalanced with a higher relapse rate for patients whose pathogen is a nonfermenter. The bacterial burden causing an infection has a substantial impact on treatment outcome and resistance selection. We describe the baseline bronchoalveolar lavage (BAL) fluid burden of organisms in suspected VABP patients screened for inclusion in a clinical trial. We measured the urea concentrations in plasma and BAL fluid to provide an index of the dilution of the bacterial and drug concentrations in the lung epithelial lining fluid introduced by the BAL procedure. We were then able to calculate the true bacterial burden as the diluted colony count times the dilution factor. The median dilution factor was 28.7, with the interquartile range (IQR) being 11.9 to 53.2. Median dilution factor-corrected colony counts were 6.18 log10(CFU/ml) [IQR, 5.43 to 6.46 log10(CFU/ml)]. In a subset of patients, repeat BAL on day 5 showed a good stability of the dilution factor. We previously showed that large bacterial burdens reduce or stop bacterial killing by granulocytes. (This study has been registered at ClinicalTrials.gov under registration no. NCT01570192.).


Assuntos
Técnicas Bacteriológicas/métodos , Líquido da Lavagem Broncoalveolar/microbiologia , Pneumonia Bacteriana/microbiologia , Pneumonia Associada à Ventilação Mecânica/microbiologia , Ureia/análise , Carga Bacteriana , Humanos , Pneumonia Bacteriana/tratamento farmacológico , Pneumonia Associada à Ventilação Mecânica/tratamento farmacológico , Ureia/sangue
20.
J Clin Microbiol ; 56(6)2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29563198

RESUMO

We evaluated the correlation between MIC and disk diffusion inhibition zones when testing ceftazidime-avibactam, using the 30/20-µg disk and the disk diffusion and MIC breakpoints established by the U.S. FDA and the Clinical and Laboratory Standards Institute (CLSI). Organisms used included 2 groups of Enterobacteriaceae isolates and 2 groups of Pseudomonas aeruginosa isolates; 1 group of each consisted of randomly selected isolates and the second group consisted of a challenge group from thousands of surveillance isolates with an increased proportion of organisms displaying ceftazidime-avibactam MIC values close to the breakpoints. Broth microdilution, disk diffusion tests, and data analysis were performed according to reference standardized methods. Ceftazidime-avibactam breakpoints of ≤8/4 (susceptible) and ≥16/4 µg/ml (resistant) for MIC and ≥21/≤20 mm for disk diffusion, as established by the U.S. FDA and the CLSI, were applied for Enterobacteriaceae and P. aeruginosa Ceftazidime-avibactam MIC and disk zone (30/20-µg disk) correlation were acceptable when testing Enterobacteriaceae (overall, very major [VM] and major [Ma] error rates of 0.4% and 0.0%, respectively) and nearly so when testing P. aeruginosa (2.3% VM and 2.9% Ma errors). In summary, disk diffusion and broth microdilution testing results demonstrated good categorical agreement for ceftazidime-avibactam against Enterobacteriaceae and P. aeruginosa, using 30/20-µg disks.


Assuntos
Antibacterianos/farmacologia , Compostos Azabicíclicos/farmacologia , Ceftazidima/farmacologia , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão/métodos , Enterobacteriaceae/efeitos dos fármacos , Testes de Sensibilidade Microbiana/métodos , Pseudomonas aeruginosa/efeitos dos fármacos , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão/normas , Combinação de Medicamentos , Humanos , Testes de Sensibilidade Microbiana/normas , Estados Unidos , United States Food and Drug Administration
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