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1.
Development ; 151(20)2024 Oct 15.
Article in English | MEDLINE | ID: mdl-38619327

ABSTRACT

Tissue morphogenesis is intimately linked to the changes in shape and organisation of individual cells. In curved epithelia, cells can intercalate along their own apicobasal axes, adopting a shape named 'scutoid' that allows energy minimization in the tissue. Although several geometric and biophysical factors have been associated with this 3D reorganisation, the dynamic changes underlying scutoid formation in 3D epithelial packing remain poorly understood. Here, we use live imaging of the sea star embryo coupled with deep learning-based segmentation to dissect the relative contributions of cell density, tissue compaction and cell proliferation on epithelial architecture. We find that tissue compaction, which naturally occurs in the embryo, is necessary for the appearance of scutoids. Physical compression experiments identify cell density as the factor promoting scutoid formation at a global level. Finally, the comparison of the developing embryo with computational models indicates that the increase in the proportion of scutoids is directly associated with cell divisions. Our results suggest that apico-basal intercalations appearing immediately after mitosis may help accommodate the new cells within the tissue. We propose that proliferation in a compact epithelium induces 3D cell rearrangements during development.


Subject(s)
Cell Proliferation , Embryo, Nonmammalian , Morphogenesis , Animals , Epithelium , Embryo, Nonmammalian/cytology , Cell Count , Starfish/embryology , Epithelial Cells/cytology , Epithelial Cells/metabolism , Cell Division
2.
Proc Natl Acad Sci U S A ; 120(1): e2216701120, 2023 01 03.
Article in English | MEDLINE | ID: mdl-36574678

ABSTRACT

The marine pelagic compartment spans numerous trophic levels and consists of numerous reticulate connections between species from primary producers to iconic apex predators, while the benthic compartment is perceived to be simpler in structure and comprised of only low trophic level species. Here, we challenge this paradigm by illustrating that the benthic compartment is home to a subweb of similar structure and complexity to that of the pelagic realm, including the benthic equivalent to iconic polar bears: megafaunal-predatory sea stars.


Subject(s)
Ursidae , Animals , Predatory Behavior , Food Chain , Ecosystem
3.
Development ; 149(22)2022 11 15.
Article in English | MEDLINE | ID: mdl-36399063

ABSTRACT

Echinoderms represent a broad phylum with many tractable features to test evolutionary changes and constraints. Here, we present a single-cell RNA-sequencing analysis of early development in the sea star Patiria miniata, to complement the recent analysis of two sea urchin species. We identified 20 cell states across six developmental stages from 8 hpf to mid-gastrula stage, using the analysis of 25,703 cells. The clusters were assigned cell states based on known marker gene expression and by in situ RNA hybridization. We found that early (morula, 8-14 hpf) and late (blastula-to-mid-gastrula) cell states are transcriptionally distinct. Cells surrounding the blastopore undergo rapid cell state changes that include endomesoderm diversification. Of particular import to understanding germ cell specification is that we never see Nodal pathway members within Nanos/Vasa-positive cells in the region known to give rise to the primordial germ cells (PGCs). The results from this work contrast the results of PGC specification in the sea urchin, and the dataset presented here enables deeper comparative studies in tractable developmental models for testing a variety of developmental mechanisms.


Subject(s)
Gene Expression Regulation, Developmental , Starfish , Animals , Starfish/genetics , Sea Urchins/genetics , Germ Cells/metabolism , RNA/genetics
4.
Brief Bioinform ; 24(3)2023 05 19.
Article in English | MEDLINE | ID: mdl-37122066

ABSTRACT

Peptide-major histocompatibility complex I (MHC I) binding affinity prediction is crucial for vaccine development, but existing methods face limitations such as small datasets, model overfitting due to excessive parameters and suboptimal performance. Here, we present STMHCPan (STAR-MHCPan), an open-source package based on the Star-Transformer model, for MHC I binding peptide prediction. Our approach introduces an attention mechanism to improve the deep learning network architecture and performance in antigen prediction. Compared with classical deep learning algorithms, STMHCPan exhibits improved performance with fewer parameters in receptor affinity training. Furthermore, STMHCPan outperforms existing ligand benchmark datasets identified by mass spectrometry. It can also handle peptides of arbitrary length and is highly scalable for predicting T-cell responses. Our software is freely available for use, training and extension through Github (https://github.com/Luckysoutheast/STMHCPan.git).


Subject(s)
Algorithms , Peptides , Alleles , Peptides/chemistry , Protein Binding , Software
5.
Brief Bioinform ; 24(4)2023 07 20.
Article in English | MEDLINE | ID: mdl-37200156

ABSTRACT

Multiple sequence alignment is widely used for sequence analysis, such as identifying important sites and phylogenetic analysis. Traditional methods, such as progressive alignment, are time-consuming. To address this issue, we introduce StarTree, a novel method to fast construct a guide tree by combining sequence clustering and hierarchical clustering. Furthermore, we develop a new heuristic similar region detection algorithm using the FM-index and apply the k-banded dynamic program to the profile alignment. We also introduce a win-win alignment algorithm that applies the central star strategy within the clusters to fast the alignment process, then uses the progressive strategy to align the central-aligned profiles, guaranteeing the final alignment's accuracy. We present WMSA 2 based on these improvements and compare the speed and accuracy with other popular methods. The results show that the guide tree made by the StarTree clustering method can lead to better accuracy than that of PartTree while consuming less time and memory than that of UPGMA and mBed methods on datasets with thousands of sequences. During the alignment of simulated data sets, WMSA 2 can consume less time and memory while ranking at the top of Q and TC scores. The WMSA 2 is still better at the time, and memory efficiency on the real datasets and ranks at the top on the average sum of pairs score. For the alignment of 1 million SARS-CoV-2 genomes, the win-win mode of WMSA 2 significantly decreased the consumption time than the former version. The source code and data are available at https://github.com/malabz/WMSA2.


Subject(s)
COVID-19 , RNA , Humans , Sequence Alignment , Phylogeny , SARS-CoV-2/genetics , Software , Algorithms , DNA/genetics
6.
Nano Lett ; 24(11): 3355-3360, 2024 Mar 20.
Article in English | MEDLINE | ID: mdl-38427975

ABSTRACT

Motivated by recent experimental breakthroughs, we propose a strategy for designing two-dimensional spin-lattices with competing interactions that lead to nontrivial emergent quantum states. We consider S = 1/2 nanographenes with C3 symmetry as building blocks, and we leverage the potential to control both the sign and the strength of exchange with first neighbors to build a family of spin models. Specifically, we consider the case of a Heisenberg model in a triangle-decorated honeycomb lattice with competing ferromagnetic and antiferromagnetic interactions whose ratio can be varied in a wide range. On the basis of the exact diagonalization of both Fermionic and spin models, we predict a quantum phase transition between a valence bond crystal of spin singlets with triplon excitations living in a Kagomé lattice and a Néel phase of effective S = 3/2 in the limit of dominant ferromagnetic interactions.

7.
Nano Lett ; 24(36): 11279-11285, 2024 Sep 11.
Article in English | MEDLINE | ID: mdl-39145763

ABSTRACT

We present a novel approach to induce charge density waves (CDWs) in metallic MA2Z4 materials, resembling the behavior observed in transition metal dichalcogenides (TMDCs). This method leverages the intercalating architecture to maintain the same crystal field and Fermi surface topologies. Our investigation reveals that CDW instability in these materials arises from electron-phonon coupling (EPC) between the d band and longitudinal acoustic (LA) phonons, mirroring TMDC's behavior. By combining α-MA2Z4 with 1H-MX2 materials in a predictive CDW phase diagram using critical EPC constants, we demonstrate the feasibility of extending CDW across material families with comparable crystal fields and reveal the crucial role in CDW instability of the competition between ionic charge transfer and electron correlation. We further uncover a strain-induced Mott transition in ß2-NbGe2N4 monolayer featuring star-of-David patterns. This work highlights the potential of intercalating architecture to engineer CDW materials, expanding our understanding of CDW instability and correlation physics.

8.
J Biol Chem ; 299(12): 105467, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37979913

ABSTRACT

In this study, we integrated machine learning (ML), structure-tissue selectivity-activity-relationship (STAR), and wet lab synthesis/testing to design a gastrointestinal (GI) locally activating JAK inhibitor for ulcerative colitis treatment. The JAK inhibitor achieves site-specific efficacy through high local GI tissue selectivity while minimizing the requirement for JAK isoform specificity to reduce systemic toxicity. We used the ML model (CoGT) to classify whether the designed compounds were inhibitors or noninhibitors. Then we used the regression ML model (MTATFP) to predict their IC50 against related JAK isoforms of predicted JAK inhibitors. The ML model predicted MMT3-72, which was retained in the GI tract, to be a weak JAK1 inhibitor, while MMT3-72-M2, which accumulated in only GI tissues, was predicted to be an inhibitor of JAK1/2 and TYK2. ML docking methods were applied to simulate their docking poses in JAK isoforms. Application of these ML models enabled us to limit our synthetic efforts to MMT3-72 and MMT3-72-M2 for subsequent wet lab testing. The kinase assay confirmed MMT3-72 weakly inhibited JAK1, and MMT3-72-M2 inhibited JAK1/2 and TYK2. We found that MMT3-72 accumulated in the GI lumen, but not in GI tissue or plasma, but released MMT3-72-M2 accumulated in colon tissue with minimal exposure in the plasma. MMT3-72 achieved superior efficacy and reduced p-STAT3 in DSS-induced colitis. Overall, the integration of ML, the structure-tissue selectivity-activity-relationship system, and wet lab synthesis/testing could minimize the effort in the optimization of a JAK inhibitor to treat colitis. This site-specific inhibitor reduces systemic toxicity by minimizing the need for JAK isoform specificity.


Subject(s)
Colitis, Ulcerative , Drug Design , Janus Kinase Inhibitors , Humans , Colitis, Ulcerative/drug therapy , Janus Kinase 1 , Janus Kinase 2 , Janus Kinase Inhibitors/pharmacology , Protein Isoforms , Machine Learning , Structure-Activity Relationship
9.
Am J Transplant ; 24(2): 190-212, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37704059

ABSTRACT

The Organ Procurement and Transplantation Network conducts a robust death verification process when augmenting the United States transplant registry with external sources of data. Process enhancements added over 35,000 externally verified deaths across waitlist candidates and transplant recipients for all organs beginning in April 2022. Ninety-four percent of added posttransplant deaths occurred beyond 5 years posttransplant, and over 74% occurred beyond 10 years. Deceased donor solid organ recipients transplanted from January 1, 2010, through October 31, 2020, were analyzed from January and July 2022 Organ Procurement and Transplantation Network Standard Transplant Analysis and Research and the Scientific Registry of Transplant Recipients Standard Analysis Files to quantify the impact of including vs excluding unverified deaths (not releasable to researchers) on posttransplant patient survival estimates. Across all organs, 1- and 5-year posttransplant survival rates were not substantially impacted; meaningful differences were observed in 10-year survival among kidney recipients. These findings bear important implications for anyone who utilized transplant registry data to examine long-term outcomes prior to the updated verification process. Users of transplant surveillance data should interpret results of long-term outcomes cautiously, particularly differences across subpopulations, and the transplant community should identify ways to improve data quality and minimize the reporting burden on transplant institutions.


Subject(s)
Tissue and Organ Procurement , Humans , United States/epidemiology , Registries , Transplant Recipients , Survival Rate , Tissue Donors
10.
BMC Med ; 22(1): 372, 2024 Sep 11.
Article in English | MEDLINE | ID: mdl-39256836

ABSTRACT

BACKGROUND: Dietary risk factors are the leading cause of death globally and in New Zealand (NZ). Processed packaged foods are prevalent in the food supply and contribute excess amounts of sodium, saturated fat, and sugar in diets. Improving the nutritional quality of these foods has the potential to reduce population chronic disease risk. We aimed to evaluate the healthiness using the Australasian Health Star Rating (HSR, from 0.5 to 5 stars, with 5 being the healthiest) and nutrient composition (sodium, saturated fat, and total sugar) of packaged products manufactured by the largest NZ-based food and beverage companies in NZ 2015-2019. This analysis relates to a larger study evaluating structured engagement with food companies to improve nutrition-related policies and actions. METHODS: Data was sourced from Nutritrack, a NZ-branded supermarket-sourced food composition database. The largest NZ-based companies from annual retail sales revenue (n = 35) were identified using 2019 Euromonitor data. All relevant products of the selected companies were extracted for analysis. Products included totalled 17,795 with a yearly range of 3462-3672 products. The primary outcome was a nutrient profile score estimated using HSR. Healthiness was defined as ≥ 3.5 stars. Secondary outcomes were sodium, total sugar, and saturated fat per 100 g/100 mL. All outcomes were assessed overall, by food company, and food category. Change over time was tested using linear mixed models, adjusting for major food categories and cluster effects of food companies controlling for multiple comparisons. Model-adjusted mean differences between years were estimated with 95% confidence intervals. RESULTS: There was a small statistically significant increase in mean HSR between 2015 and 2019 (0.08 [0.15,0.01], p = 0.024). Mean total sugar content decreased over the same period (0.78 g/100 g [0.08,1.47], p = 0.020), but there were no significant changes in mean sodium or saturated fat contents. Seven of the 13 categories showed small increases in mean HSR (0.1-0.2). Most categories (9/13) exhibited a reduction in mean total sugar content. CONCLUSIONS: Between 2015 and 2019, there were slight improvements in the nutritional quality of selected packaged foods and drinks in NZ. Much more substantive changes are needed to address the health-related burden of unhealthy diets, supported by stronger government action and less reliance on voluntary industry initiatives.


Subject(s)
Nutritive Value , New Zealand , Humans , Beverages/economics , Food Packaging , Food Industry/trends , Nutrients/analysis , Food
11.
Small ; : e2404804, 2024 Jul 23.
Article in English | MEDLINE | ID: mdl-39040003

ABSTRACT

Herein, a three-armed amphiphilic metallacycle-cored star supramolecular polymer (Por-MOM-PDMAEMA) has been designed and synthesized via highly efficient post-assembly polymerization. This star polymer is further self-assembled into nanoparticles of different sizes depending upon the experimental conditions. The gas-controlled morphology transformation and tunable antibacterial activities of Por-MOM-PDMAEMAis systematically investigated and compared with metallacycle (MOM). The superior antibacterial activity of Por-MOM-PDMAEMA against multidrug-resistant P. aeruginosa implies that the presence of photodynamic photosensitizer (Por) and cationic polymer chain will significantly enhance antibactericidal activity, which is mainly attributed to the synergistic effect of photosensitizer and polymer chain linked in one metallacycle core. By leveraging the unique properties of metallacycle and their dynamic response to gaseous stimuli, the antibacterial properties of the Por-MOM-PDMAEMA can be finely tuned in response to gas triggers.

12.
Biol Reprod ; 110(1): 116-129, 2024 Jan 13.
Article in English | MEDLINE | ID: mdl-37801702

ABSTRACT

Ovarian hyperstimulation syndrome (OHSS) is a life-threatening and potentially fatal complication during in vitro fertilization treatment. The levels of transforming growth factor-ß1 (TGF-ß1) are upregulated in human follicular fluid and granulosa-lutein cells (hGL) of OHSS patients and could contribute to the development of OHSS by downregulating steroidogenic acute regulatory protein (StAR) expression. However, whether the same is true for the other two members of the TGF-ß family, TGF-ß2 and -ß3, remains unknown. We showed that all three TGF-ß isoforms were expressed in human follicular fluid. In comparison, TGF-ß1 was expressed at the highest level, followed by TGF-ß2 and TGF-ß3. Compared to non-OHSS patients, follicular fluid levels of TGF-ß1 and TGF-ß3 were significantly upregulated in OHSS patients. The same results were observed in mRNA levels of TGF-ß isoforms in hGL cells and ovaries of OHSS rats. In addition, StAR mRNA levels were upregulated in hGL cells of OHSS patients and the ovaries of OHSS rats. Treatment cells with TGF-ß isoforms downregulated the StAR expression with a comparable effect. Moreover, activations of SMAD3 signaling were required for TGF-ß isoforms-induced downregulation of StAR expression. This study indicates that follicular fluid TGF-ß1 and TGF-ß3 levels could be used as biomarkers and therapeutic targets for the OHSS.


Subject(s)
Ovarian Hyperstimulation Syndrome , Transforming Growth Factor beta1 , Female , Humans , Rats , Animals , Transforming Growth Factor beta1/genetics , Transforming Growth Factor beta1/metabolism , Transforming Growth Factor beta3/genetics , Transforming Growth Factor beta3/metabolism , Transforming Growth Factor beta2/genetics , Transforming Growth Factor beta2/metabolism , Ovarian Hyperstimulation Syndrome/genetics , RNA, Messenger/metabolism , Protein Isoforms
13.
New Phytol ; 2024 Jul 26.
Article in English | MEDLINE | ID: mdl-39060950

ABSTRACT

The ALMT1 transporter aids malate secretion, chelating Al3+ ions to form nontoxic Al-malate complexes, believed to exclude Al from the roots. However, the extent to which malate secreted by ALMT1 is solely used for the exclusion of Al3+ or can be reutilized by plant roots for internal Al tolerance remains uncertain. In our investigation, we explored the impact of malate secretion on both external and internal Al resistance in Arabidopsis thaliana. Additionally, we delved into the mechanism by which the tonoplast-localized bacterial-type ATP-binding cassette (ABC) transporter complex STAR1/ALS3 promotes the degradation of the Al resistance transcription factor STOP1 to regulate ALMT1 expression. Our study demonstrates that the level of secreted malate influences whether the Al-malate complex is excluded from the roots or transported into root cells. The nodulin 26-like intrinsic protein (NIP) subfamily members NIP1;1 and NIP1;2, located in the plasma membrane, coordinate with STAR1/ALS3 to facilitate Al-malate transport from root apoplasm to the symplasm and eventually to the vacuoles for the internal Al detoxification. ALS3-dependent STAR1 interacts with and promotes the degradation of STOP1, regulating malate exudation. Our findings demonstrate the dual roles of malate exudation in external Al exclusion and Al absorption for internal Al detoxification.

14.
Clin Endocrinol (Oxf) ; 101(2): 108-113, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38796770

ABSTRACT

BACKGROUND: Newborn screening (NBS) reduces the risk of mortality in congenital adrenal hyperplasia (CAH), mainly due to the salt-wasting form of 21-hydroxylase deficiency. There is limited knowledge regarding the results of NBS in non-CAH primary adrenal insufficiency (non-CAH PAI). PATIENTS AND METHODS: Clinical and NBS for CAH data of neonates who were diagnosed with non-CAH PAI between January and December 2022 were examined. RESULTS: Patients (n = 6, 4 females) were presented with severe hyperpigmentation (n = 6), hypoglycemia (n = 4), hyponatremia (n = 3), hyperkalemia (n = 1), respiratory distress syndrome (n = 1) between 3rd hour to 2 months of life. All had normal NBS results. The median first-tier 17-hydroxyprogesterone (17OHP) concentration in NBS for CAH was 0.14 ng/mL (range; 0.05-0.85). Molecular studies revealed biallelic mutations in the MC2R (n = 4; 3 homozygous, 1 compound heterozygous), MRAP (n = 1) and STAR (n = 1) genes. Glucocorticoid with or without mineralocorticoid replacement was initiated once the diagnosis of non-CAH PAI was established. CONCLUSION: Neonates with non-CAH PAI have always normal NBS due to persistently low 17OHP, even when these newborn infants are severely symptomatic for adrenal insufficiency. Clinicians should be alert for signs of adrenal insufficiency in neonates, even if the patient has a 'normal' screening for CAH, so as not to delay diagnosis and treatment. This fact should be kept in mind particularly in countries where these conditions are more common than elsewhere.


Subject(s)
Adrenal Hyperplasia, Congenital , Adrenal Insufficiency , Neonatal Screening , Humans , Infant, Newborn , Neonatal Screening/methods , Female , Male , Adrenal Hyperplasia, Congenital/diagnosis , Adrenal Hyperplasia, Congenital/genetics , Adrenal Hyperplasia, Congenital/blood , Adrenal Insufficiency/diagnosis , Adrenal Insufficiency/blood , 17-alpha-Hydroxyprogesterone/blood , Mutation
15.
Clin Endocrinol (Oxf) ; 100(5): 431-440, 2024 May.
Article in English | MEDLINE | ID: mdl-38368602

ABSTRACT

OBJECTIVE: Lipoid congenital adrenal hyperplasia (LCAH) is caused by mutations in STAR. A systematic review of phenotype-genotype correlation and data on testicular histology in LCAH patients is unavailable. We aim to describe our experience and provide phenotype-genotype correlation. DESIGN, PATIENTS AND MEASUREMENTS: Retrospective review of three genetically proven LCAH patients from our centre and per-patient data analysis from a systematic review of 292 probands. The phenotypic subgroups of 46,XY were Group A (typical female genitalia), Group B (atypical genitalia) and Group C (typical male genitalia). RESULTS: We report three new LCAH probands from India, all diagnosed post-infancy with preserved gonadal function and one novel variant. The systematic review reports 46,XY to 46,XX LCAH ratio of 1.1 (155:140). Patients with 46,XY LCAH in Group A were diagnosed in infancy (116/117) and had higher mineralocorticoid involvement than Group C (96.4% vs. 75%, p = 0.035), whereas Group C had preserved gonadal function. Hyperplastic adrenals are noted in ~60% of LCAH diagnosed with primary adrenal insufficiency in infancy. There was no report of gonadal germ cell cancer and rare reports of germ cell neoplasia in situ in adolescents, especially with intraabdominal gonads. Two-thirds of LCAH probands were East-Asian and 11/16 regional recurrent variants were from East Asia. There was minimal overlap between variants in Groups A (n = 55), B (n = 9) and C (n = 8). All nonsense and frameshift and most of the splice-site variants and deletion/insertions were present in Group A. CONCLUSIONS: We report three new cases of LCAH from India. We propose a phenotype-derived genotypic classification of reported STAR variants in 46,XY LCAH.


Subject(s)
Adrenal Hyperplasia, Congenital , Disorder of Sex Development, 46,XY , Adolescent , Humans , Male , Female , Adrenal Hyperplasia, Congenital/diagnosis , Mutation/genetics , Phosphoproteins/genetics , Phosphoproteins/metabolism , Phenotype , Genotype
16.
Chemistry ; 30(5): e202303375, 2024 Jan 22.
Article in English | MEDLINE | ID: mdl-37889092

ABSTRACT

A unique gyroid cubic phase has been discovered for a discotic star mesogen with three covalently attached DNA bases. In this cubic I a 3 ‾ d ${Ia\bar{3}d}$ phase, the conjugated core of the mesogens and the thymine pseudo guests self-assemble in mirror image continuous networks, representing a semiconducting material with three-dimensional transport pathways. The hole carrier mobilities are found to be in the typical range of poly(phenylenevinylene) scaffolds. This structure is stabilized by a weak hydrogen bonding between the thymine bases and can be switched to a columnar liquid crystal - thermally and by the addition of complementary adenine guests.

17.
Chemistry ; : e202401349, 2024 Jul 06.
Article in English | MEDLINE | ID: mdl-38970416

ABSTRACT

Two star-shaped mesogens with a (meso-tetraphenylporphinato) zinc (II) core and bithiophene conjugated arms with 3,4,5-trisdodecyloxyphenyl periphery were synthesized. One of these molecules was decorated with four fullerenes via an aliphatic spacer. This is the sterically overcrowded compound with an octapodal morphology. The other star lacks the fullerenes and provides free space between the conjugated arms. This mesogen does not aggregate in solution, but in solid state it forms a hexagonal columnar and a highly ordered oblique helical columnar phase, while the octopus molecule assembles in an amorphous solid. Photophysical studies of the octapodal compound in solution and the solid thin film reveal the formation of J-type aggregates, in which the interaction between donors (porphyrin) and acceptors (fullerene) dominates leading to absorption bands in the NIR region of the spectra. The mixture of both compounds results in a self-assembly which is called the Click procedure. Fullerenes of the octopus nanosegregate in the pockets of the star mesogens generating hexagonal columnar structures with a regular stacking along the columnar axis. Thus providing free space is a tool to control the competition between supramolecular interactions and nanosegregation. Such liquid-crystalline donor-acceptor structures may play a role in future LC photovoltaic applications.

18.
J Gen Intern Med ; 2024 Jul 19.
Article in English | MEDLINE | ID: mdl-39028405

ABSTRACT

BACKGROUND: Medicare beneficiaries are increasingly enrolling in Medicare Advantage (MA), which employs a wide range of practices around restriction of the networks of providers that beneficiaries visit. Though Medicare beneficiaries highly value provider choice, it is unknown whether the MA contract quality metrics which beneficiaries use to inform their contract selection capture the restrictiveness of contracts' provider networks. OBJECTIVE: We evaluated whether there are meaningful associations between provider network restrictiveness (across primary care, psychiatry, and endocrinology providers) and contracts' overall star quality rating, as well as between network restrictiveness and contracts' performance on access to care measures from the Consumer Assessment of Healthcare Providers and Systems (CAHPS) survey. PARTICIPANTS: Medicare Advantage contracts with health maintenance organization (HMO), local preferred provider organization (PPO), and point of service (POS) plans with available data. DESIGN: A cross-sectional analysis using multivariable linear regressions to assess the relationship between provider network restrictiveness and contract quality scores in 2013 through 2017. MEASURES: Statistical significance in the relationship between network restrictiveness and contract performance on quality measures. RESULTS: Across all study years, we included 562 unique contracts and 2801 contract-years. We find no evidence of consistent relationships between MA physician network restrictiveness and contract star rating. For primary care, psychiatry, and endocrinology, respectively, a 10 percentage point increase in restrictiveness was associated with a 0.02 (95% confidence interval [CI] -0.01 to 0.04), 0.0008 (95% CI, -0.01 to 0.02), and -0.01 (95% CI, -0.01 to 0.001) difference in star rating (p-value > 0.05 for all). Similarly, we find no evidence of consistent relationships between network restrictiveness and access to care measures. CONCLUSIONS: Our findings suggest that existing MA contract quality measures are not useful for indicating differences in network restrictiveness. Given the importance of provider choice to beneficiaries, more specific metrics may be needed to facilitate informed decisions about MA coverage.

19.
J Hum Evol ; 187: 103490, 2024 02.
Article in English | MEDLINE | ID: mdl-38266614

ABSTRACT

A frequent source of debate in paleoanthropology concerns the taxonomic unity of fossil assemblages, with many hominin samples exhibiting elevated levels of variation that can be interpreted as indicating the presence of multiple species. By contrast, the large assemblage of hominin fossils from the Rising Star cave system, assigned to Homo naledi, exhibits a remarkably low degree of variation for most skeletal elements. Many factors can contribute to low sample variation, including genetic drift, strong natural selection, biased sex ratios, and sampling of closely related individuals. In this study, we tested for potential sex-biased sampling in the Rising Star dental sample. We compared coefficients of variation for the H. naledi teeth to those for eight extant hominoid samples. We used a resampling procedure that generated samples from the extant taxa that matched the sample size of the fossil sample for each possible Rising Star dental sex ratio. We found that variation at four H. naledi tooth positions-I2, M1, P4, M1-is so low that the possibility that one sex is represented by few or no individuals in the sample cannot be excluded. Additional evidence is needed to corroborate this inference, such as ancient DNA or enamel proteome data, and our study design does not address other potential factors that would account for low sample variation. Nevertheless, our results highlight the importance of considering the taphonomic history of a hominin assemblage and suggest that sex-biased sampling is a plausible explanation for the low level of phenotypic variation found in some aspects of the current H. naledi assemblage.


Subject(s)
Hominidae , Tooth , Humans , Animals , Fossils , Genetic Drift , Molar , Tooth, Deciduous
20.
Mol Pharm ; 21(6): 3027-3039, 2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38755753

ABSTRACT

This study presents a novel approach by utilizing poly(vinylpyrrolidone)s (PVPs) with various topologies as potential matrices for the liquid crystalline (LC) active pharmaceutical ingredient itraconazole (ITZ). We examined amorphous solid dispersions (ASDs) composed of ITZ and (i) self-synthesized linear PVP, (ii) self-synthesized star-shaped PVP, and (iii) commercial linear PVP K30. Differential scanning calorimetry, X-ray diffraction, and broad-band dielectric spectroscopy were employed to get a comprehensive insight into the thermal and structural properties, as well as global and local molecular dynamics of ITZ-PVP systems. The primary objective was to assess the influence of PVPs' topology and the composition of ASD on the LC ordering, changes in the temperature of transitions between mesophases, the rate of their restoration, and finally the solubility of ITZ in the prepared ASDs. Our research clearly showed that regardless of the PVP type, both LC transitions, from smectic (Sm) to nematic (N) and from N to isotropic (I) phases, are effectively suppressed. Moreover, a significant difference in the miscibility of different PVPs with the investigated API was found. This phenomenon also affected the solubility of API, which was the greatest, up to 100 µg/mL in the case of starPVP 85:15 w/w mixture in comparison to neat crystalline API (5 µg/mL). Obtained data emphasize the crucial role of the polymer's topology in designing new pharmaceutical formulations.


Subject(s)
Calorimetry, Differential Scanning , Itraconazole , Liquid Crystals , Povidone , Solubility , X-Ray Diffraction , Itraconazole/chemistry , Liquid Crystals/chemistry , Povidone/chemistry , Calorimetry, Differential Scanning/methods , X-Ray Diffraction/methods , Polymers/chemistry , Antifungal Agents/chemistry , Drug Compounding/methods , Crystallization , Chemistry, Pharmaceutical/methods
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