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1.
Int J Cancer ; 155(6): 1045-1052, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38703351

RESUMEN

A diagnosis of brain metastasis (BM) significantly affects quality of life in patients with metastatic renal cell cancer (mRCC). Although systemic treatments have shown efficacy in mRCC, active surveillance (AS) is still commonly used in clinical practice. In this single-center cohort study, we assessed the impact of different initial treatment strategies for metastatic RCC (mRCC) on the development of BM. All consecutive patients diagnosed with mRCC between 2011 and 2022 were included at the Erasmus MC Cancer Institute, the Netherlands, and a subgroup of patients with BM was selected. In total, 381 patients with mRCC (ECM, BM, or both) were identified. Forty-six patients had BM of whom 39 had metachronous BM (diagnosed ≥1 month after ECM). Twenty-five (64.1%) of these 39 patients with metachronous BM had received prior systemic treatment for ECM and 14 (35.9%) patients were treatment naive at BM diagnosis. The median BM-free survival since ECM diagnosis was significantly longer (p = .02) in previously treated patients (29.0 [IQR 12.6-57.0] months) compared to treatment naive patients (6.8 [IQR 1.0-7.0] months). In conclusion, patients with mRCC who received systemic treatment for ECM prior to BM diagnosis had a longer BM-free survival as compared to treatment naïve patients. These results emphasize the need for careful evaluation of treatment strategies, and especially AS, for patients with mRCC.


Asunto(s)
Neoplasias Encefálicas , Carcinoma de Células Renales , Neoplasias Renales , Humanos , Carcinoma de Células Renales/secundario , Carcinoma de Células Renales/patología , Carcinoma de Células Renales/tratamiento farmacológico , Carcinoma de Células Renales/terapia , Neoplasias Encefálicas/secundario , Neoplasias Encefálicas/terapia , Masculino , Femenino , Neoplasias Renales/patología , Persona de Mediana Edad , Anciano , Calidad de Vida , Estudios Retrospectivos , Países Bajos/epidemiología
2.
Mol Ecol ; 33(4): e17252, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38146927

RESUMEN

Circadian regulation is linked to local environmental adaptation, and many species with broad climatic niches display variation in circadian genes. Here, we hypothesize that lichenizing fungi occupying different climate zones tune their metabolism to local environmental conditions with the help of their circadian systems. We study two species of the genus Umbilicaria occupying similar climatic niches (Mediterranean and the cold temperate) in different continents. Using homology to Neurospora crassa genes, we identify gene sets associated with circadian rhythms (11 core, 39 peripheral genes) as well as temperature response (37 genes). Nucleotide diversity of these genes is significantly correlated with mean annual temperature, minimum temperature of the coldest month and mean temperature of the coldest quarter. Furthermore, we identify altitudinal clines in allele frequencies in several non-synonymous substitutions in core clock components, for example, white collar-like, frh-like and various ccg-like genes. A dN/dS approach revealed a few significant peripheral clock- and temperature-associated genes (e.g. ras-1-like, gna-1-like) that may play a role in fine-tuning the circadian clock and temperature-response machinery. An analysis of allele frequency changes demonstrated the strongest evidence for differentiation above the genomic background in the clock-associated genes in U. pustulata. These results highlight the likely relevance of the circadian clock in environmental adaptation, particularly frost tolerance, of lichens. Whether or not the fungal clock modulates the symbiotic interaction within the lichen consortium remains to be investigated. We corroborate the finding of genetic variation in clock components along altitude-not only latitude-as has been reported in other species.


Asunto(s)
Relojes Circadianos , Neurospora crassa , Relojes Circadianos/genética , Temperatura , Ritmo Circadiano/genética , Neurospora crassa/genética , Genómica , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo
3.
Plant Dis ; 108(2): 375-381, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37578371

RESUMEN

Sterol demethylation inhibitor (DMI) fungicides continue to be essential components for the control of brown rot of peach caused by Monilinia fructicola in the United States and worldwide. In the southeastern United States, resistance to DMIs had been associated with overexpression of the cytochrome P450 14α-demethylase gene MfCYP51 as well as the genetic element Mona, a 65 bp in length nucleotide sequence located upstream of MfCYP51 in resistant isolates. About 20 years after the first survey, we reevaluated sensitivity of M. fructicola from South Carolina and Georgia to propiconazole and also evaluated isolates from Alabama for the first time. A total of 238 M. fructicola isolates were collected from various commercial and two experimental orchards, and sensitivity to propiconazole was determined based on a discriminatory dose of 0.3 µg/ml. Results indicated 16.2, 89.2, and 72.4% of isolates from Alabama, Georgia, and South Carolina, respectively, were resistant to propiconazole. The detection of resistance in Alabama is the first report for the state. All resistant isolates contained Mona, but it was absent from most sensitive isolates. It was unclear if the resistance frequency had increased in South Carolina and Georgia. However, the resistance levels (as assessed by the isolate frequency in discriminatory dose-based relative growth categories) did not change notably, and no evidence of other resistance genotypes was found. Analysis of the upstream MfCYP51 gene region in the resistant isolate CF010 revealed an insertion sequence described for the first time in this report. Our study suggests that current fungicide spray programs have been effective against increasing resistance levels in populations of M. fructicola and suppressing development of new resistant genotypes of the pathogen.


Asunto(s)
Ascomicetos , Fungicidas Industriales , Triazoles , Estados Unidos , Fungicidas Industriales/farmacología , Ascomicetos/genética , Georgia
4.
Neuromodulation ; 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38441505

RESUMEN

OBJECTIVES: Intrathecal opioids delivered by implanted pumps are used to treat malignant or nonmalignant chronic pain. In this study, we 1) review a case in which intrathecal infusions of sufentanil along with other adjuvants were used and after an extended period led to an intrathecal mass and 2) compared and contrasted the potential mechanisms for these phenomena. MATERIALS AND METHODS: A woman aged 66 years with a history of scoliosis and multiple spine surgeries was treated with an implantable drug delivery system for treating persistent pain after laminectomy. The patient received intrathecal medication comprising sufentanil, bupivacaine, and clonidine. RESULTS: Intrathecal therapy over approximately ten years served to reduce pain and improve function over the treatment period. After the extended treatment interval, the patient developed an intrathecal mass that was associated with impairment. The mass was surgically removed. Systematic histopathology revealed the space-occupying mass to largely comprise fibroblasts and some inflammatory cells embedded in a collagen mass located proximally to the catheter tip. CONCLUSIONS: To our knowledge, this is the first published case report of sufentanil causing this complication. The science and mechanism of intrathecal catheter tip-associated mass formation and associated clinical research correlates are reviewed in detail, and explanations for this phenomenon are proposed based on histochemical analysis of the patient's pathology findings.

5.
Am J Transplant ; 23(9): 1388-1400, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37257653

RESUMEN

Technological advances in the field of histocompatibility have allowed us to define anti-human leukocyte antigen (HLA) antibody specificity at the allelic level. However, how allele-specific antibodies affect organ allocation is poorly studied. We examined allelic specificities of class I HLA antibodies in 6726 consecutive serum samples from 2953 transplant candidates and evaluated their impact on the corresponding crossmatch and organ allocation. Out of 17 class I HLA antigens represented by >1 allele in the LABScreen single antigen bead assay, 12 had potential allele-specific reactivity. Taking advantage of our unbiased cohort of deceased donor-candidate testing (123,135 complement-dependent cytotoxicity crossmatches between 2014 and 2017), we estimated that the presence of allele-specific antibody detected using a single antigen bead assay (median fluorescence intensity, >3000) against only the rare allele was a poor predictor of a positive complement-dependent cytotoxicity crossmatch, with a positive predictive value of 0% to 7%, compared with 52.5% in allele-concordant class I HLA antibodies against A or B locus antigens. Further, we confirmed allele-specific reactivity using flow crossmatch in 3 scenarios: A11:01/A11:02, A68:01/A68:02, and B44:02/B44:03. Our results suggest that allele-specific antibodies may unnecessarily exclude transplant candidates (up to 10%) from organ offers by overcalling unacceptable antigens; incorporation of selective reactivity pattern in allocation may promote precision matching and more equitable allocation.


Asunto(s)
Antígenos de Histocompatibilidad Clase I , Isoanticuerpos , Humanos , Alelos , Prueba de Histocompatibilidad/métodos , Antígenos de Histocompatibilidad Clase I/genética , Antígenos HLA/genética , Antígenos
6.
Am J Transplant ; 23(4): 512-519, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36732087

RESUMEN

ABO compatibility is important for kidney transplantation, with longer waitlist times for blood group B kidney transplant candidates. However, kidneys from non-A1 (eg, A2) subtype donors, which express less A antigen, can be safely transplanted into group B recipients. ABO subtyping is routinely performed using anti-A1 lectin, but DNA-based genotyping is also possible. Here, we compare lectin and genotyping testing. Lectin and genotype subtyping was performed on 554 group A deceased donor samples at 2 transplant laboratories. The findings were supported by 2 additional data sets of 210 group A living kidney donors and 124 samples with unclear lectin testing sent to a reference laboratory. In deceased donors, genotyping found 65% more A2 donors than lectin testing, most with weak lectin reactivity, a finding supported in living donors and samples sent for reference testing. DNA sequencing and flow cytometry showed that the discordances were because of several factors, including transfusion, small variability in A antigen levels, and rare ABO∗A2.06 and ABO∗A2.16 sequences. Although lectin testing is the current standard for transplantation subtyping, genotyping is accurate and could increase A2 kidney transplant opportunities for group B candidates, a difference that should reduce group B wait times and improve transplant equity.


Asunto(s)
Trasplante de Riñón , Humanos , Genotipo , Incompatibilidad de Grupos Sanguíneos , Donantes de Tejidos , Donadores Vivos , Sistema del Grupo Sanguíneo ABO/genética , Isoanticuerpos
7.
Heredity (Edinb) ; 130(1): 40-52, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36494489

RESUMEN

How do nascent species evolve reproductive isolation during speciation with on-going gene flow? How do hybrid lineages become stabilised hybrid species? While commonly used genomic approaches provide an indirect way to identify species incompatibility factors, synthetic hybrids generated from interspecific crosses allow direct pinpointing of phenotypic traits involved in incompatibilities and the traits that are potentially adaptive in hybrid species. Here we report the analysis of phenotypic variation and hybrid breakdown in crosses between closely-related Senecio aethnensis and S. chrysanthemifolius, and their homoploid hybrid species, S. squalidus. The two former species represent a likely case of recent (<200 ky) speciation with gene flow driven by adaptation to contrasting conditions of high- and low-elevations on Mount Etna, Sicily. As these species form viable and fertile hybrids, it remains unclear whether they have started to evolve reproductive incompatibility. Our analysis represents the first study of phenotypic variation and hybrid breakdown involving multiple Senecio hybrid families. It revealed wide range of variation in multiple traits, including the traits previously unrecorded in synthetic hybrids. Leaf shape, highly distinct between S. aethnensis and S. chrysanthemifolius, was extremely variable in F2 hybrids, but more consistent in S. squalidus. Our study demonstrates that interspecific incompatibilities can evolve rapidly despite on-going gene flow between the species. Further work is necessary to understand the genetic bases of these incompatibilities and their role in speciation with gene flow.


Asunto(s)
Flujo Génico , Senecio , Humanos , Sicilia , Senecio/genética , Hibridación Genética , Fenotipo , Especiación Genética
8.
Pestic Biochem Physiol ; 197: 105642, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38072561

RESUMEN

Methyl benzimidazole carbamate (MBC) fungicides were once widely used for brown rot (Monilinia fructicola) control of peach (Prunus persica (L.) Batsch) in the southeastern US, but their use was substantially reduced and often eliminated due to widespread resistance. In this study, 233 M. fructicola isolates were collected from major peach production areas in Alabama, Georgia, and South Carolina, and sensitivity to thiophanate-methyl was examined. Isolates were also collected from one organic and two experimental peach orchards. A discriminatory dose of 1 µg/ml was used to distinguish sensitive (S) and moderately sensitive (S-LR) isolates from low resistant phenotypes, while 50 and 500 µg/ml thiophanate-methyl concentrations were used to determine high resistant (HR) phenotypes. Sequence analyses were performed to identify mutations in the ß-tubulin target gene and detached fruit assays were performed to determine the efficacy of a commercial product against isolates representing each phenotype. Results indicated 55.7%, 63.5%, and 75.9% of isolates from Alabama, Georgia, and South Carolina, respectively, were S to thiophanate-methyl; 44.3%, 36.5%, and 21.4% were S-LR; no isolates were LR; and only 3 isolates (1.3%) from South Carolina were HR. No mutations in S or S-LR isolates were found, but HR isolates revealed the E198A mutation, an amino acid change of glutamic acid to alanine conferring high resistance. The high label rate of a commercial product containing thiophanate-methyl controlled brown rot caused by S and S-LR isolates in detached fruit studies but was ineffective against HR isolates. The combinations of thiophanate-methyl with azoxystrobin or isofetamid, when mixed together and applied in an experimental orchard 14 days preharvest, significantly reduced brown rot incidence on pre and postharvest commercially ripe fruit and efficacy was comparable to that of a grower standard fungicide. These results indicate that thiophanate-methyl may again be useful to peach growers in the southeastern US for brown rot and fungicide resistance management.


Asunto(s)
Fungicidas Industriales , Prunus persica , Tiofanato/farmacología , Fungicidas Industriales/farmacología , Sudeste de Estados Unidos
9.
Plant Dis ; 107(2): 326-334, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35771113

RESUMEN

Peach is an important specialty fruit crop in the United States, and phony peach disease (PPD), caused by Xylella fastidiosa subsp. multiplex, has been a major cause of yield loss since it was first observed in 1885. Under a federal eradication program, surveys of PPD were conducted from 1929 to 1972, when the program was terminated. No surveys have been conducted in approximately 50 years; therefore, the current prevalence of PPD in the United States is unknown, especially in the Southeast, where damage was previously most severe. To ascertain the status of PPD, we surveyed orchards in Alabama, Florida, Georgia, and South Carolina from June to August 2020 and, except for South Carolina and northern Georgia, PPD was prevalent. Trees in 17 orchards were subjected to confirmation of X. fastidiosa using the AmplifyRP XRT+ for X. fastidiosa to corroborate our visual assessments; based on these tests, PPD incidence in the orchards ranged from 0 to 30.5%. Ancillary written surveys of relative PPD presence and prevalence were sent to fruit pathologists from universities in 20 states where PPD was historically reported. Only 35.0% of respondents reported that PPD either currently or recently occurred in their state and, of these, three reported PPD to be of significant concern. The results of the physical and written surveys indicate that PPD remains prevalent mainly in the southeastern region of the United States but, in other states where previously reported, it is either not present or has very low prevalence when compared with historical accounts of the disease.


Asunto(s)
Prunus persica , Xylella , Estados Unidos , Prevalencia , South Carolina
10.
Neuromodulation ; 26(7): 1400-1411, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37589641

RESUMEN

OBJECTIVE: This study aimed to assess the safety and effectiveness of a new charge-distributed multiphase stimulation paradigm during an extended spinal cord stimulation (SCS) trial. MATERIALS AND METHODS: This prospective, multicenter, randomized, single-blind, feasibility study included participants with chronic low back and/or leg pain and baseline numerical rating scale (NRS) for overall pain intensity ≥6. After a successful commercial SCS trial, participants were randomized to multiphase SCS therapy A (approximately 600-1500 Hz) or B (approximately 300-600 Hz), delivered via an investigational external pulse generator and existing leads during an 11-to-12-day testing period. Primary end points were mean NRS change from baseline to final in-office visit for each multiphase therapy and between therapies. Secondary end points included mean NRS change from end of commercial trial to final study visit and incidence of device-related adverse events (AEs). Additional measures included patient-reported outcomes collected at home through electronic watches and written diaries. Power usage was compared between multiphase and commercial therapies. RESULTS: A total of 122 participants initiated a commercial trial; 77 were randomized to a multiphase arm, and 65 completed the study. Reductions in mean NRS scores from baseline to final study visit were significant for multiphase therapy A and B (-4.3 and -4.7, respectively; both p < 0.0001). There was no statistically significant difference in mean NRS reduction or percent pain relief between multiphase therapies. In an additional analysis, 63.9% of participants reported greater pain relief with multiphase than with commercial SCS therapy in the at-home setting. On average, multiphase required less power than did commercial devices. One non-serious device-related AE was reported, and no infections occurred during the extended trial. CONCLUSIONS: Multiphase SCS effectively reduced pain in participants with chronic low back and/or leg pain during a trial, with no unanticipated device-related AEs reported. Future studies should evaluate long-term effectiveness of multiphase stimulation. CLINICAL TRIAL REGISTRATION: The Clinicaltrials.gov registration number for the study is NCT03594266.


Asunto(s)
Dolor Crónico , Estimulación de la Médula Espinal , Humanos , Estimulación de la Médula Espinal/efectos adversos , Estimulación de la Médula Espinal/métodos , Dolor Crónico/diagnóstico , Dolor Crónico/terapia , Pierna , Estudios Prospectivos , Método Simple Ciego , Resultado del Tratamiento , Médula Espinal
11.
Curr Issues Mol Biol ; 44(8): 3648-3665, 2022 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-36005146

RESUMEN

Breast cancer is the leading cause of cancer death among women worldwide. Multiple extrinsic and intrinsic factors are associated with this disease's development. Various research groups worldwide have reported the presence of human papillomavirus (HPV) DNA in samples of malignant breast tumors. Although its role in mammary carcinogenesis is not fully understood, it is known that the HPV genome, once inserted into host cells, has oncogenic capabilities. The present study aimed to detect the presence of HPV DNA in 116 breast tissue biopsies and classify them according to their histology. It was found that 50.9% of the breast biopsies analyzed were malignant neoplasms, of which 74.6% were histologically classified as infiltrating ductal carcinoma. In biopsies with non-malignant breast disease, fibroadenoma was the most common benign neoplasm (39.1%). Detection of HPV DNA was performed through nested PCR using the external primer MY09/11 and the internal primer GP5+/6+. A hybridization assay genotyped HPV. HPV DNA was identified in 20.3% (12/59) of malignant neoplasms and 35% non-malignant breast disease (16/46). It was also detected in 27.3% (3/11) of breast tissue biopsies without alteration. However, there are no statistically significant differences between these groups and the existence of HPV DNA (p = 0.2521). Its presence was more frequent in non-malignant alterations than in malignant neoplasias. The most frequent genotypes in the HPV-positive samples were low-risk (LR) HPV-42 followed by high-risk (HR) HPV-31.

12.
J Comput Assist Tomogr ; 46(2): 224-230, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35081601

RESUMEN

OBJECTIVE: This study aimed to evaluate distal triceps tendon tear patterns using a systematic classification based on the tendon's layered structure. METHODS: We retrospectively identified Magnetic resonance imaging (MRI) examinations with triceps tendon tears that underwent reconstructive surgery. Magnetic resonance images were reviewed independently by 2 musculoskeletal radiologists to determine tendon layer involvement and ancillary findings, including tear size, involvement of triceps lateral expansion, and presence of olecranon bursal fluid. Surgical reports were scrutinized for level of anatomic detail and correlation with imaging findings. RESULTS: We identified 69 triceps tendon tears in 68 subjects (61 men, 7 women; mean age, 45 ± 12 years) who underwent surgical reconstruction. On MRI, the superficial layer was always involved with either a partial or full-thickness tear. The most common tear pattern was a combination of superficial layer full-thickness tear with deep layer partial tear (25 of 69 [36%]). Mean tear length was 24 ± 12 mm. We found no cases of isolated deep layer tears. Involvement of triceps lateral expansion and presence of bursal fluid correlated positively with tear severity of superficial and deep layers (P < 0.001). Detailed surgical correlation was limited, with only 9 of 69 (13%) of surgical reports containing information specifically addressing individual tendon layers. CONCLUSIONS: Triceps tendon tears show tear patterns following its layered structure and can be assessed by MRI. Radiologists and surgeons are encouraged to describe tear patterns considering both superficial and deep tendon layers.


Asunto(s)
Articulación del Codo , Lesiones del Manguito de los Rotadores , Adulto , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Rotura/diagnóstico por imagen , Tendones/diagnóstico por imagen
13.
Neuromodulation ; 25(8): 1410-1420, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34056781

RESUMEN

OBJECTIVES: This study investigated the efficacy of a transcutaneous electrical nerve stimulation (TENS) device (Quell®) for persons with symptoms due to fibromyalgia (FM). MATERIALS AND METHODS: One hundred nineteen (N = 119) subjects were randomly assigned to use an active (N = 62) or sham (N = 57) TENS for three months. All subjects completed baseline questionnaires and were administered quantitative sensory testing (QST). Subjects completed the Patients' Global Impression of Change (PGIC, primary outcome measure) and other mailed questionnaires (secondary outcome measures) at six weeks and three months. RESULTS: The subjects averaged 50.4 ± 13.5 years of age, 93.3% were female, and 79.8% were Caucasian. Most showed benefit from using the TENS, but no differences between groups were found on the primary outcome measure after three months (active 3.87 ± 1.85, sham 3.73 ± 1.80, 95% confidence interval [CI] [-0.60, 0.88], p = 0.707). Those with more hypersensitivity showed most improvement on the PGIC at six weeks (0.22, 95% CI [0.01, 0.43], p = 0.042) and three months (0.20, 95% CI [0.00, 0.41], p = 0.049) and among those with higher sensitivity based on QST, the active TENS group showed the most benefit with TENS compared with the sham treatment (1.20, 95% CI [0.22, 2.18], p = 0.017). No TENS-related serious adverse events were reported. Subjects in the sham group correctly identified their treatment 87.5% of the time, while, surprisingly, subjects in the active group correctly identified their treatment only 17.4% of the time. CONCLUSION: This study found no differences between those who were exposed to maximal-frequency active stimulation or minimal-frequency sham stimulation from a wearable TENS in reducing FM-related symptoms. However, those with greater hypersensitivity showed most benefit from TENS. Additional studies to help determine the role individual differences play in the use of TENS in managing FM-related symptoms are needed.


Asunto(s)
Fibromialgia , Estimulación Eléctrica Transcutánea del Nervio , Dispositivos Electrónicos Vestibles , Humanos , Femenino , Anciano de 80 o más Años , Masculino , Fibromialgia/diagnóstico , Fibromialgia/terapia , Dolor , Manejo del Dolor
14.
J Minim Invasive Gynecol ; 28(7): 1285-1290, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34029745

RESUMEN

STUDY OBJECTIVE: Simulation-based assessment is poised for application in educational promotion and credentialing in gynecologic surgery. With high-stakes assessment, validation necessitates evidence, not just about the trustworthiness of decisions but of beneficial consequences to education and healthcare as well. In this paper, we unpack the modern conceptualization of validity as it pertains to surgical simulation and high-stakes competency assessment. DESIGN: N/A SETTING: N/A PATIENTS: N/A INTERVENTIONS: N/A MEASUREMENTS AND MAIN RESULTS: N/A CONCLUSION: Validity in high-stakes simulation-based assessment necessitates evidence, not just about the trustworthiness of score-based decisions but of beneficial consequences to education and healthcare as well.


Asunto(s)
Competencia Clínica , Procedimientos Quirúrgicos Ginecológicos , Simulación por Computador , Habilitación Profesional , Evaluación Educacional , Femenino , Humanos , Reproducibilidad de los Resultados
15.
Skeletal Radiol ; 50(1): 97-106, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32638058

RESUMEN

OBJECTIVE: To examine the effect of external hip rotation on ischiofemoral (IF) and quadratus femoris (QF) spaces using real-time kinematic MRI, with the hypothesis that hips with IF and QF space narrowing have distinct motion patterns compared with control hips. MATERIALS AND METHODS: This prospective study was IRB-approved and complied with HIPAA guidelines. We recruited women (≥ 18 years) with and without ischiofemoral impingement to undergo kinematic MRI of the hips. A kinematic imaging protocol using T2-HASTE was performed beginning at maximal internal rotation followed by active external hip rotation. The duration of each acquisition was 30 s, providing 8 images/3 s. IF and QF spaces, and femoral metaphyseal and lesser trochanter centroid coordinates were measured on sequential images. Hips were classified as controls or narrowed based on IF and QF space thresholds and compared statistically throughout motion stages. RESULTS: The cohort comprised 12 women (24 hips; 10 control and 14 narrowed hips) aged 58 ± 10 years. External rotation caused IF space reduction of 59% in narrowed hips versus 41% in control hips. QF space decreased 71% in narrowed hips versus 50% in control hips. IF and QF spaces differed significantly between groups only when external rotation exceeded the neutral position (P < 0.02 for both). The lesser trochanter terminated more posteriorly in narrowed hips compared with controls (P = 0.03). CONCLUSIONS: Kinematic MRI during external hip rotation in women with narrowed and control hips reveals dynamic differences in IF and QF spaces and lesser trochanter terminal position.


Asunto(s)
Pinzamiento Femoroacetabular , Imagen por Resonancia Magnética , Fenómenos Biomecánicos , Femenino , Fémur/diagnóstico por imagen , Articulación de la Cadera/diagnóstico por imagen , Humanos , Estudios Prospectivos
16.
Heart Lung Circ ; 30(1): 115-120, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31401051

RESUMEN

BACKGROUND: Gender differences in valvular heart disease are increasingly recognised. A prior study has suggested better surgical outcomes in women with symptomatic aortic stenosis (AS). We investigate gender differences in medically managed severe AS. METHOD: We studied 347 patients with severe AS (aortic valve area index <0.6 cm2/m2) in terms of baseline clinical background, echocardiographic characteristics, and clinical outcomes. Appropriate univariate and multivariate models were employed, while Kaplan-Meier curves were constructed to compare mortality outcomes. RESULTS: In total, 205 (59%) patients were women. Despite higher incidences of hypertension (75.6% vs 47.3%) and diabetes mellitus (46.5% vs 29.5%) in women, women had improved survival (Kaplan-Meier log-rank = 6.24, p = 0.012). After adjusting for age (hazard ratio [HR], 1.034; 95% confidence interval [CI], 1.014-1.054), hypertension (HR, 1.469; 95% CI, 0.807-2.673), diabetes (HR, 1.219; 95% CI, 0.693-2.145), and indexed aortic valve area (HR 0.145, 95% CI 0.031-0.684) on multivariate analyses, female gender remained independently associated with lower mortality (HR, 0.561; 95%, CI 0.332-0.947). Women tended to have smaller body surface area (BSA), left ventricular (LV) internal diastolic diameter, and smaller LV outflow tract diameter but were similar to men in terms of LV ejection fraction, AS severity, and patterns of LV remodelling. CONCLUSIONS: Women appeared to have better outcomes compared to men in medically managed severe AS. These gender differences warrant further study and may affect prognosis, follow-up, and timing of valve surgery.


Asunto(s)
Estenosis de la Válvula Aórtica/terapia , Válvula Aórtica/cirugía , Manejo de la Enfermedad , Función Ventricular Izquierda/fisiología , Anciano , Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/diagnóstico , Estenosis de la Válvula Aórtica/epidemiología , Diástole , Ecocardiografía , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Factores Sexuales , Singapur/epidemiología , Volumen Sistólico/fisiología , Tasa de Supervivencia/tendencias
17.
Mol Ecol ; 29(2): 394-412, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31793091

RESUMEN

Recently diverged species present particularly informative systems for studying speciation and maintenance of genetic divergence in the face of gene flow. We investigated speciation in two closely related Senecio species, S. aethnensis and S. chrysanthemifolius, which grow at high and low elevations, respectively, on Mount Etna, Sicily and form a hybrid zone at intermediate elevations. We used a newly generated genome-wide single nucleotide polymorphism (SNP) dataset from 192 individuals collected over 18 localities along an elevational gradient to reconstruct the likely history of speciation, identify highly differentiated SNPs, and estimate the strength of divergent selection. We found that speciation in this system involved heterogeneous and bidirectional gene flow along the genome, and species experienced marked population size changes in the past. Furthermore, we identified highly-differentiated SNPs between the species, some of which are located in genes potentially involved in ecological differences between species (such as photosynthesis and UV response). We analysed the shape of these SNPs' allele frequency clines along the elevational gradient. These clines show significantly variable coincidence and concordance, indicative of the presence of multifarious selective forces. Selection against hybrids is estimated to be very strong (0.16-0.78) and one of the highest reported in literature. The combination of strong cumulative selection across the genome and previously identified intrinsic incompatibilities probably work together to maintain the genetic and phenotypic differentiation between these species - pointing to the importance of considering both intrinsic and extrinsic factors when studying divergence and speciation.


Asunto(s)
Flujo Génico/genética , Senecio/genética , Adaptación Fisiológica/genética , Adaptación Fisiológica/fisiología , Frecuencia de los Genes/genética , Polimorfismo de Nucleótido Simple/genética
18.
Br J Surg ; 107(7): 793-800, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32463143

RESUMEN

BACKGROUND: Organ transplantation is predicted to increase as life expectancy and the incidence of chronic diseases rises. Regenerative medicine-inspired technologies challenge the efficacy of the current allograft transplantation model. METHODS: A literature review was conducted using the PubMed interface of MEDLINE from the National Library of Medicine. Results were examined for relevance to innovations of organ bioengineering to inform analysis of advances in regenerative medicine affecting organ transplantation. Data reports from the Scientific Registry of Transplant Recipient and Organ Procurement Transplantation Network from 2008 to 2019 of kidney, pancreas, liver, heart, lung and intestine transplants performed, and patients currently on waiting lists for respective organs, were reviewed to demonstrate the shortage and need for transplantable organs. RESULTS: Regenerative medicine technologies aim to repair and regenerate poorly functioning organs. One goal is to achieve an immunosuppression-free state to improve quality of life, reduce complications and toxicities, and eliminate the cost of lifelong antirejection therapy. Innovative strategies include decellularization to fabricate acellular scaffolds that will be used as a template for organ manufacturing, three-dimensional printing and interspecies blastocyst complementation. Induced pluripotent stem cells are an innovation in stem cell technology which mitigate both the ethical concerns associated with embryonic stem cells and the limitation of other progenitor cells, which lack pluripotency. Regenerative medicine technologies hold promise in a wide array of fields and applications, such as promoting regeneration of native cell lines, growth of new tissue or organs, modelling of disease states, and augmenting the viability of existing ex vivo transplanted organs. CONCLUSION: The future of organ bioengineering relies on furthering understanding of organogenesis, in vivo regeneration, regenerative immunology and long-term monitoring of implanted bioengineered organs.


Asunto(s)
Órganos Artificiales , Trasplante de Órganos , Medicina Regenerativa , Ingeniería Biomédica , Humanos , Trasplante de Órganos/métodos , Medicina Regenerativa/métodos
19.
Heredity (Edinb) ; 125(4): 227-239, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32641721

RESUMEN

An understanding of genetic structure is essential for answering many questions in population genetics. However, complex population dynamics and scale-dependent processes can make it difficult to detect if there are distinct genetic clusters present in natural populations. Inferring discrete population structure is particularly challenging in the presence of continuous genetic variation such as isolation by distance. Here, we use the plant species Mimulus guttatus as a case study for understanding genetic structure at three spatial scales. We use reduced-representation sequencing and marker-based genotyping to understand dispersal dynamics and to characterise genetic structure. Our results provide insight into the spatial scale of genetic structure in a widespread plant species, and demonstrate how dispersal affects spatial genetic variation at the local, regional, and range-wide scale. At a fine-spatial scale, we show dispersal is rampant with little evidence of spatial genetic structure within populations. At a regional-scale, we show continuous differentiation driven by isolation by distance over hundreds of kilometres, with broad geographic genetic clusters that span major barriers to dispersal. Across Western North America, we observe geographic genetic structure and the genetic signature of multiple postglacial recolonisation events, with historical gene flow linking isolated populations. Our genetic analyses show M. guttatus is highly dispersive and maintains large metapopulations with high intrapopulation variation. This high diversity and dispersal confounds the inference of genetic structure, with multi-level sampling and spatially-explicit analyses required to understand population history.


Asunto(s)
Variación Genética , Genética de Población , Mimulus , Flujo Génico , Repeticiones de Microsatélite , Mimulus/genética , América del Norte
20.
Am J Bot ; 107(3): 456-465, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32133624

RESUMEN

PREMISE: Species delimitation in parasitic organisms is challenging because traits used to identify species are often plastic and vary depending on the host. Here, we use species from a recent radiation of generalist hemiparasitic Euphrasia to investigate trait variation and trait plasticity. We tested whether Euphrasia species show reliable trait differences, investigated whether these differences correspond to life history trade-offs between growth and reproduction, and quantified plasticity in response to host species. METHODS: Common garden experiments were used to evaluate trait differences between 11 Euphrasia taxa grown on a common host, document phenotypic plasticity when a single Euphrasia species is grown on eight different hosts, and relate observations to trait differences recorded in the wild. RESULTS: Euphrasia exhibited variation in life history strategies; some individuals transitioned rapidly to flowering at the expense of early season growth, while others invested in vegetative growth and delayed flowering. Life history differences were present between some species, though many related taxa lacked clear trait differences. Species differences were further blurred by phenotypic plasticity-many traits were plastic and changed with host type or between environments. CONCLUSIONS: Phenotypic plasticity in response to host and environment confounds species delimitation in Euphrasia. When grown in a common garden environment, some morphologically distinct taxa can be identified, though others represent morphologically similar shallow segregates. Trait differences present between some species and populations demonstrate the rapid evolution of distinct life history strategies in response to local ecological conditions.


Asunto(s)
Euphrasia , Adaptación Fisiológica , Fenotipo , Reproducción , Especificidad de la Especie
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