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1.
2.
Elife ; 132024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38483448

RESUMEN

Genome-wide association studies (GWAS) identified thousands of genetic variants linked to phenotypic traits and disease risk. However, mechanistic understanding of how GWAS variants influence complex morphological traits and can, in certain cases, simultaneously confer normal-range phenotypic variation and disease predisposition, is still largely lacking. Here, we focus on rs6740960, a single nucleotide polymorphism (SNP) at the 2p21 locus, which in GWAS studies has been associated both with normal-range variation in jaw shape and with an increased risk of non-syndromic orofacial clefting. Using in vitro derived embryonic cell types relevant for human facial morphogenesis, we show that this SNP resides in an enhancer that regulates chondrocytic expression of PKDCC - a gene encoding a tyrosine kinase involved in chondrogenesis and skeletal development. In agreement, we demonstrate that the rs6740960 SNP is sufficient to confer chondrocyte-specific differences in PKDCC expression. By deploying dense landmark morphometric analysis of skull elements in mice, we show that changes in Pkdcc dosage are associated with quantitative changes in the maxilla, mandible, and palatine bone shape that are concordant with the facial phenotypes and disease predisposition seen in humans. We further demonstrate that the frequency of the rs6740960 variant strongly deviated among different human populations, and that the activity of its cognate enhancer diverged in hominids. Our study provides a mechanistic explanation of how a common SNP can mediate normal-range and disease-associated morphological variation, with implications for the evolution of human facial features.


Asunto(s)
Condrogénesis , Estudio de Asociación del Genoma Completo , Animales , Humanos , Ratones , Condrogénesis/genética , Cara , Cabeza , Cráneo
3.
J Cell Biol ; 223(5)2024 05 06.
Artículo en Inglés | MEDLINE | ID: mdl-38334958

RESUMEN

Mutant RAS are major contributors to cancer and signal primarily from nanoclusters on the plasma membrane (PM). Their C-terminal membrane anchors are main features of membrane association. However, the same RAS isoform bound to different guanine nucleotides spatially segregate. Different RAS nanoclusters all enrich a phospholipid, phosphatidylserine (PS). These findings suggest more complex membrane interactions. Our electron microscopy-spatial analysis shows that wild-types, G12V mutants, and membrane anchors of isoforms HRAS, KRAS4A, and KRAS4B prefer distinct PS species. Mechanistically, reorientation of KRAS4B G-domain exposes distinct residues, such as Arg 135 in orientation state 1 (OS1) and Arg 73/Arg 102 in OS2, to the PM and differentially facilitates the recognition of PS acyl chains. Allele-specific oncogenic mutations of KRAS4B also shift G-domain reorientation equilibrium. Indeed, KRAS4BG12V, KRAS4BG12D, KRAS4BG12C, KRAS4BG13D, and KRAS4BQ61H associate with PM lipids with headgroup and acyl chain specificities. Distribution of these KRAS4B oncogenic mutants favors different nanoscale membrane topography. Thus, RAS G-domains allosterically facilitate membrane lateral distribution.


Asunto(s)
Membrana Celular , Lípidos de la Membrana , Proteínas Proto-Oncogénicas p21(ras) , Membrana Celular/metabolismo , Lípidos de la Membrana/metabolismo , Isoformas de Proteínas/metabolismo , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Animales
4.
Cureus ; 16(1): e52823, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38406096

RESUMEN

Hereditary hemochromatosis (HH) is characterized by elevated iron absorption in the body, leading to iron accumulation with subsequent dysfunction and end-organ damage. While the progression of the disease can result in arthralgias, hepatomegaly, cardiomyopathies, and diabetes, over a third of HH patients present with cutaneous manifestations. We present the case of a 56-year-old male with HH who presented to dermatology with a rash and diffuse scaling. The patient exhibited brown plate-like scales clinically consistent with diffuse ichthyosis vulgaris. While ichthyosis has been seen in patients with idiopathic hemochromatosis, its association with HH is not well reported. Due to the high prevalence of cutaneous involvement in hereditary hemochromatosis, physicians should familiarize themselves with ichthyosis and the other dermatologic manifestations of this disease.

5.
Proc (Bayl Univ Med Cent) ; 37(1): 101-103, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38173992

RESUMEN

Background: Medical students who are exposed to value-based care early in their education may be more likely to practice it. Our study aimed to understand medical students' knowledge of and ability to implement the principles of high-value care in clinical settings. Additionally, we assessed students' confidence in using high-value care practices to both influence care decisions and educate patients. Methods: We surveyed third-year medical students at Texas A&M School of Medicine during their clerkship rotations using a 7-question Likert-scale survey. Students were asked to evaluate their confidence in performing cost-conscious high-value care behaviors. Results: Of the 114 students offered the survey, 34 (30%) completed it fully. The greatest variance in response occurred in students' attitudes toward their role in controlling healthcare costs. Half of respondents agreed or strongly agreed that they played a part in cost control as medical students, with 35% somewhat or strongly disagreeing. A majority of students felt confident initiating a conversation about costs with patients, while 21% somewhat or strongly disagreed that they were confident. Conclusion: Overall, our results reveal that the main area lacking in students' education in value-based care is instilling the belief that they, as medical students, have a role to play in controlling healthcare costs.

6.
JAAD Case Rep ; 42: 106-108, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38090661
7.
J Adolesc Young Adult Oncol ; 12(6): 912-917, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37852000

RESUMEN

Young adult (YA) cancer survivors experience worse financial outcomes than older survivors. This analysis used data from Expect Miracles Foundation to explore the impact of one-time financial grants on financial well-being and access to health care. Among 300 respondents, the average grant was $1526 (standard deviation = $587; range $300-$3000). Respondents reported improved ability to pay expenses (t = 4.45, p < 0.001), increased financial decision-making power (t = 2.79, p = 0.06), decreased medical debt impact (t = 2.1, p = 0.04), improved transportation access (t = 2.38, p = 0.02), and fewer challenges in accessing care (t = 3.0, p = 0.005) 6 months after receiving a financial grant. Financial assistance offers YAs an opportunity to meet medical and nonmedical expenses.


Asunto(s)
Supervivientes de Cáncer , Neoplasias , Humanos , Adulto Joven , Sobrevivientes
9.
Indian J Palliat Care ; 29(3): 292-311, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37700900

RESUMEN

Objectives: Patient Health Questionnaire-9 (PHQ-9) in Indian settings is yet not very often used in palliative care with the Hindi-speaking population. The Hindi version of PHQ-9 is available but its cultural adaptation to the Hindi-speaking population in North India receiving palliative care services is required to be tested. PHQ-9 as a depression screening questionnaire may help to identify depression symptoms among patients with cancer. This study aimed to examine the cultural equivalence of PHQ-9 Hindi for use with patients with cancer receiving palliative care services in North India. Material and Methods: Based on the standard methodology of translation and adaptation of the scale, the following process was used: (i) Two focused group discussions with 17 experts working in a cancer palliative care setting, (ii) qualitative interviewing with 11 patients, and (iii) research team review. All interviews were audio recorded, transcribed, and item-wise content analysis was conducted. Results: A few difficult phrases in the original PHQ-9 were 'dilchaspi', 'avasadgrast', 'kam urja', 'nakaam', parivar ko neecha dhikhana and 'ashthir' which were changed to Kam Mann Lagna, Mann Dukhi hona, kamjori, saksham nahi hain' 'asafal', Parivar ko nirash karna' and 'bechain,' respectively. Two items, namely no. 6 and 8 were changed to shorten the length for appropriately conveying the meaning. Conclusion: Hindi language involves various dialects which change from region to region bringing variations in understanding the meaning of the words. It is recommended that culturally equivalent scales are used in practice and research. PHQ-9 is now culturally adapted for the Hindi-speaking population in North India. PHQ-9 will help identidy depressive symptoms at an early stage. Psychometric testing of PHQ-9 is underway.

10.
ACS Mater Lett ; 5(9): 2408-2421, 2023 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-37680545

RESUMEN

High power conversion efficiencies (PCE), low energy payback time (EPBT), and low manufacturing costs render perovskite solar cells (PSCs) competitive; however, a relatively low operational stability impedes their large-scale deployment. In addition, state-of-the-art PSCs are made of expensive materials, including the organic hole transport materials (HTMs) and the noble metals used as the charge collection electrode, which induce degradation in PSCs. Thus, developing inexpensive alternatives is crucial to fostering the transition from academic research to industrial development. Combining a carbon-based electrode with an inorganic HTM has shown the highest potential and should replace noble metals and organic HTMs. In this review, we illustrate the incorporation of a carbon layer as a back contact instead of noble metals and inorganic HTMs instead of organic ones as two cornerstones for achieving optimal stability and economic viability for PSCs. We discuss the primary considerations for the selection of the absorbing layer as well as the electron-transporting layer to be compatible with the champion designs and ultimate architecture for single-junction PSCs. More studies regarding the long-term stability are still required. Using the recommended device architecture presented in this work would pave the way toward constructing low-cost and stable PSCs.

11.
Oman J Ophthalmol ; 16(2): 326-328, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37602175

RESUMEN

An 18-year-old male diagnosed with acrodermatitis enteropathica (AE) since early childhood presented with worsening of dermatitis along with photophobia and watering in both eyes. Systemic evaluation by dermatology and gastroenterology specialists confirmed a diagnosis of acute exacerbation of AE, and oral zinc supplements were initiated. A best-corrected visual acuity of 20/20 was documented in both eyes. Slit-lamp examination revealed bilateral subepithelial corneal opacities in a radial fan-like pattern extending from the superior limbus toward the center. A whorled appearance of fluorescein staining and small epithelial erosions was noted in both eyes. Ocular involvements in AE such as blepharitis, cataracts, and radial corneal opacities have been reported previously. We report a new association of AE with limbal stem cell deficiency with its classical features of linear subepithelial corneal opacities with a whorling uptake of fluorescein stain and corneal erosions.

12.
J Cancer Res Clin Oncol ; 149(15): 14137-14144, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37552310

RESUMEN

BACKGROUND: Physicians have increasingly adopted Twitter as a discussion and distribution platform for oncology research. While the influence of financial conflicts of interests (FCOI) on medical research is well documented, their role in the dissemination of research on social media platforms is not well known. In this study, we sought to evaluate the FCOIs of physicians followed by the top three oncology journals on Twitter. MATERIALS AND METHODS: We used the Open Payments Search Tool ( https://openpaymentsdata.cms.gov ) to assess FCOIs between 2016 and 2021 of United States (US) physicians followed by three oncology journals (Journal of Clinical Oncology, The Lancet Oncology, and Annals of Oncology) on Twitter. RESULTS: Of 1914 Twitter accounts followed by the top three oncology journals on Twitter, 547 (28.6%) belonged to US physicians. Of these, 463 (84.6%) received general payments between 2016 and 2021. After excluding 30 US physicians currently in residency or fellowship, this percentage increased to 88.2% (n = 456/517). Combined, the median (interquartile range) general payment amount was $8100 ($200-90,000). Additionally, over $42 million in general payments were made between 2016 and 2021. CONCLUSION: Our findings offer insight on FCOIs between oncology journals and US physicians on Twitter. These findings may serve as the foundation for future research regarding optimal medical journal conduct on social media platforms.

13.
ACS Chem Biol ; 18(9): 2082-2093, 2023 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-37579045

RESUMEN

Protein-membrane interactions (PMIs) are ubiquitous in cellular signaling. Initial steps of signal transduction cascades often rely on transient and dynamic interactions with the inner plasma membrane leaflet to populate and regulate signaling hotspots. Methods to target and modulate these interactions could yield attractive tool compounds and drug candidates. Here, we demonstrate that the conjugation of a medium-chain lipid tail to the covalent K-Ras(G12C) binder MRTX849 at a solvent-exposed site enables such direct modulation of PMIs. The conjugated lipid tail interacts with the tethered membrane and changes the relative membrane orientation and conformation of K-Ras(G12C), as shown by molecular dynamics (MD) simulation-supported NMR studies. In cells, this PMI modulation restricts the lateral mobility of K-Ras(G12C) and disrupts nanoclusters. The described strategy could be broadly applicable to selectively modulate transient PMIs.


Asunto(s)
Transducción de Señal , Proteínas ras , Proteínas ras/metabolismo , Membrana Celular/metabolismo , Simulación de Dinámica Molecular , Lípidos , Proteínas Proto-Oncogénicas p21(ras)/genética
14.
Environ Sci Pollut Res Int ; 30(37): 87866-87879, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37432577

RESUMEN

Phenolic compounds have become a severe environmental concern due to water contamination, affecting the sustainability of the ecosystem. The microalgae enzymes have enticed for the efficient involvement in the biodegradation of phenolics compound in metabolic processes. In this investigation, the oleaginous microalgae Chlorella sorokiniana was cultured heterotrophically under the influence of phenol and p-nitrophenol. The enzymatic assays of algal cell extracts were used to decipher the underlying mechanisms for phenol and p-nitrophenol biodegradation. A reduction of 99.58% and 97.21% in phenol and p-nitrophenol values, respectively, was recorded after the 10th day of microalgae cultivation. Also, the biochemical components in phenol, p-nitrophenol, and control were found to be 39.6 ± 2.3%, 36.7 ± 1.3%, and 30.9 ± 1.8% (total lipids); 27.4 ± 1.4%, 28.3 ± 1.8%, and 19.7 ± 1.5% (total carbohydrates); and 26.7 ± 1.9%, 28.3 ± 1.9%, and 39.9 ± 1.2% (total proteins), respectively. The GC-MS and 1H-NMR spectroscopy attested the incidence of fatty acid methyl esters in the synthesized microalgal biodiesel. The activity of catechol 2,3-dioxygenase and hydroquinone 1,2-dioxygenase in microalgae under heterotrophic conditions has conferred the ortho- and hydroquinone pathways for phenol and p-nitrophenol biodegradation, respectively. Also, the acceleration of fatty acid profiles in microalgae is deliberated under the impact of the phenol and p-nitrophenol biodegradation process. Thus, microalgae enzymes in the metabolic degradation process of phenolic compounds encourage ecosystem sustainability and biodiesel prospects due to the increased lipid profiles of microalgae.


Asunto(s)
Chlorella , Microalgas , Lípidos/química , Chlorella/metabolismo , Microalgas/metabolismo , Hidroquinonas , Fenol/metabolismo , Ecosistema , Biocombustibles , Ácidos Grasos/metabolismo , Procesos Heterotróficos , Fenoles/metabolismo , Biomasa
15.
Artículo en Inglés | MEDLINE | ID: mdl-37463719

RESUMEN

RAS genes are frequently mutated in cancer. The primary signaling compartment of wild-type and constitutively active oncogenic mutant RAS proteins is the inner leaflet of the plasma membrane (PM). Thus, a better understanding of the unique environment of the PM inner leaflet is important to shed further light on RAS function. Over the past few decades, an integrated approach of superresolution imaging, molecular dynamic simulations, and biophysical assays has yielded new insights into the capacity of RAS proteins to sort lipids with specific headgroups and acyl chains, to assemble signaling nanoclusters on the inner PM. RAS proteins also sense and respond to changes in components of the outer PM leaflet, including glycophosphatidylinositol-anchored proteins, sphingophospholipids, glycosphingolipids, and galectins, as well as cholesterol that translocates between the two leaflets. Such communication between the inner and outer leaflets of the PM, called interleaflet coupling, allows RAS to potentially integrate extracellular mechanical and electrostatic information with intracellular biochemical signaling events, and reciprocally allows mutant RAS-transformed tumor cells to modify tumor microenvironments. Here, we review RAS-lipid interactions and speculate on potential mechanisms that allow communication between the opposing leaflets of the PM.


Asunto(s)
Neoplasias , Proteínas ras , Humanos , Proteínas ras/genética , Proteínas ras/metabolismo , Membrana Celular/metabolismo , Neoplasias/metabolismo , Transducción de Señal , Microambiente Tumoral
16.
Healthc Technol Lett ; 10(3): 35-52, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37265835

RESUMEN

ECG is a non-invasive way of determining cardiac health by measuring the electrical activity of the heart. A novel detection technique for feature points P, QRS and T is investigated to diagnose various atrial and ventricular cardiovascular anomalies with ECG signals for ambulatory monitoring. Before the system is worthy of field trials, it is validated with several databases and recorded their response. The QRS complex detection is based on the Pan Tompkins algorithm and difference operation method that provides positive predictivity, sensitivity and false detection rate of 99.29%, 99.49% and 1.29%, respectively. Proposed novel T wave detection provides sensitivity of 97.78%. Also, proposed P wave detection provides positive predictivity, sensitivity and false detection rate of 99.43%, 99.4% and 1.15% for the control study (normal subjects) and 82.68%, 94.3% and 25.4% for the case (patients with cardiac anomalies) study, respectively. Disease detection such as arrhythmia is based on standard R-R intervals while myocardial infarction is based on the ST-T deviations where the positive predictivity, sensitivity and accuracy are observed to be 94.6%, 84.2% and 85%, respectively. It should be noted that, since the frontal leads are only used, the anterior myocardial infarction cases are detected with the injury pattern in lead avl and ST depression in reciprocal leads. Detection of atrial fibrillation is done for both short and long duration signals using statistical methods using interquartile range and standard deviations, giving very high accuracy, 100% in most cases. The system hardware for obtaining the 2 lead ECG signal is designed using commercially available off the shelf components. Small field validation of the designed system is performed at a Public Health Centre in Gujarat, India with 42 patients (both cases and controls). 78.5% accuracy was achieved during the field validation. It is thus concluded that the proposed method is ideal for improvisation in cardiac health monitoring outreach in resource constrained regions.

17.
Artículo en Inglés | MEDLINE | ID: mdl-37321232

RESUMEN

PURPOSE: Pentosan polysulfate (PPS), a drug used for interstitial cystitis, has recently been detected to cause maculopathy in a dose-dependent manner. Outer retinal atrophy is the hallmark of this condition. METHODS: History, examination and multimodal imaging were used to guide diagnosis and management. RESULTS: We report a case of PPS-related maculopathy in a 77-year-old lady, who presented with florid retinal atrophy at the posterior pole in both eyes, and a concurrent macular hole in the left eye. She had been diagnosed with interstitial cystitis several years prior for which she was prescribed PPS (Elmiron). She had noticed a drop in vision 5 years following initiation of PPS and self-discontinued the drug after 24 years of use. A diagnosis of PPS-related maculopathy with a macular hole was made. She was counselled regarding the prognosis and was advised to avoid PPS. Surgery for macular hole was deferred in view of the severe retinal atrophy. CONCLUSIONS: PPS-related maculopathy can lead to severe retinal atrophy and a subsequent degenerative macular hole. A high index of suspicion is required for early detection and cessation of drug to prevent this irreversible vision loss.

18.
Brain Behav Immun ; 112: 220-234, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37315702

RESUMEN

Originally identified in fibroblasts, Protease Inhibitor (PI)16 was recently shown to be crucial for the development of neuropathic pain via effects on blood-nerve barrier permeability and leukocyte infiltration, though its impact on inflammatory pain has not been established. Using the complete Freund's Adjuvant inflammatory pain model, we show that Pi16-/- mice are protected against sustained inflammatory pain. Accordingly, intrathecal delivery of a PI16 neutralizing antibody in wild-type mice prevented sustained CFA pain. In contrast to neuropathic pain models, we did not observe any changes in blood-nerve barrier permeability due to PI16 deletion. Instead, Pi16-/- mice display reduced macrophage density in the CFA-injected hindpaw. Furthermore, there was a significant bias toward CD206hi (anti-inflammatory) macrophages in the hindpaw and associated dorsal root ganglia. Following CFA, intrathecal depletion of CD206+ macrophages using mannosylated clodronate liposomes promoted sustained pain in Pi16-/- mice. Similarly, an IL-10 neutralizing antibody also promoted sustained CFA pain in the Pi16-/ when administered intrathecally. Collectively, our results point to fibroblast-derived PI16 mediating substantial differences in macrophage phenotype in the pain neuroaxis under conditions of inflammation. The co-expression of PI16 alongside fibroblast markers in human DRG raise the likelihood that a similar mechanism operates in human inflammatory pain states. Collectively, our findings may have implications for targeting fibroblast-immune cell crosstalk for the treatment of chronic pain.


Asunto(s)
Dolor Crónico , Neuralgia , Ratones , Humanos , Animales , Inflamación , Macrófagos , Fibroblastos , Anticuerpos Neutralizantes/farmacología , Ganglios Espinales , Hiperalgesia , Proteínas Portadoras , Glicoproteínas
19.
ACS Omega ; 8(20): 17337-17349, 2023 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-37251151

RESUMEN

Metal halide perovskites (MHPs) are exceptional semiconductors best known for their intriguing properties, such as high absorption coefficients, tunable bandgaps, excellent charge transport, and high luminescence yields. Among various MHPs, all-inorganic perovskites exhibit benefits over hybrid compositions. Notably, critical properties, including chemical and structural stability, could be improved by employing organic-cation-free MHPs in optoelectronic devices such as solar cells and light-emitting devices (LEDs). Due to their enticing features, including spectral tunability over the entire visible spectrum with high color purity, all-inorganic perovskites have become a focus of intense research for LEDs. This Review explores and discusses the application of all-inorganic CsPbX3 nanocrystals (NCs) in developing blue and white LEDs. We discuss the challenges perovskite-based LEDs (PLEDs) face and the potential strategies adopted to establish state-of-the-art synthetic routes to obtain rational control over dimensions and shape symmetry without compromising the optoelectronic properties. Finally, we emphasize the significance of matching the driving currents of different LED chips and balancing the aging and temperature of individual chips to realize efficient, uniform, and stable white electroluminescence.

20.
Sci Rep ; 13(1): 3792, 2023 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-36882465

RESUMEN

Air-cushion (AC) packaging has become widely used worldwide. ACs are air-filled, dual plastic packaging solutions commonly found surrounding and protecting items of value within shipping enclosures during transit. Herein, we report on a laboratory assessment employing ACs as a microalgal photobioreactor (PBR). Such a PBR inherently addresses many of the operational issues typically encountered with open raceway ponds and closed photobioreactors, such as evaporative water loss, external contamination, and predation. Using half-filled ACs, the performance of microalgal species Chlorella vulgaris, Nannochloropsis oculata, and Cyclotella cryptica (diatom) was examined and the ash-free dry cell weight and overall biomass productivity determined to be 2.39 g/L and 298.55 mg/L/day for N. oculata, 0.85 g/L and 141.36 mg/L/day for C. vulgaris, and 0.67 g/L and 96.08 mg/L/day for C. cryptica. Furthermore, maximum lipid productivity of 25.54 mg/L/day AFDCW and carbohydrate productivity of 53.69 mg/L/day AFDCW were achieved by C. cryptica, while maximum protein productivity of 247.42 mg/L/day AFDCW was attained by N. oculata. Data from this work will be useful in determining the applicability and life-cycle profile of repurposed and reused ACs as potential microalgal photobioreactors depending upon the end product of interest, scale utilized, and production costs.


Asunto(s)
Chlorella vulgaris , Diatomeas , Microalgas , Fotobiorreactores , Biomasa , Peso Corporal
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