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1.
Am J Hum Genet ; 111(6): 1140-1164, 2024 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-38776926

RESUMO

Detection of structural variants (SVs) is currently biased toward those that alter copy number. The relative contribution of inversions toward genetic disease is unclear. In this study, we analyzed genome sequencing data for 33,924 families with rare disease from the 100,000 Genomes Project. From a database hosting >500 million SVs, we focused on 351 genes where haploinsufficiency is a confirmed disease mechanism and identified 47 ultra-rare rearrangements that included an inversion (24 bp to 36.4 Mb, 20/47 de novo). Validation utilized a number of orthogonal approaches, including retrospective exome analysis. RNA-seq data supported the respective diagnoses for six participants. Phenotypic blending was apparent in four probands. Diagnostic odysseys were a common theme (>50 years for one individual), and targeted analysis for the specific gene had already been performed for 30% of these individuals but with no findings. We provide formal confirmation of a European founder origin for an intragenic MSH2 inversion. For two individuals with complex SVs involving the MECP2 mutational hotspot, ambiguous SV structures were resolved using long-read sequencing, influencing clinical interpretation. A de novo inversion of HOXD11-13 was uncovered in a family with Kantaputra-type mesomelic dysplasia. Lastly, a complex translocation disrupting APC and involving nine rearranged segments confirmed a clinical diagnosis for three family members and resolved a conundrum for a sibling with a single polyp. Overall, inversions play a small but notable role in rare disease, likely explaining the etiology in around 1/750 families across heterogeneous clinical cohorts.


Assuntos
Inversão Cromossômica , Doenças Raras , Humanos , Doenças Raras/genética , Masculino , Feminino , Inversão Cromossômica/genética , Linhagem , Genoma Humano , Sequenciamento Completo do Genoma , Proteína 2 de Ligação a Metil-CpG/genética , Mutação , Proteínas de Homeodomínio/genética , Pessoa de Meia-Idade
2.
Cell ; 144(5): 796-809, 2011 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-21333348

RESUMO

Interactions between bone and the reproductive system have until now been thought to be limited to the regulation of bone remodeling by the gonads. We now show that, in males, bone acts as a regulator of fertility. Using coculture assays, we demonstrate that osteoblasts are able to induce testosterone production by the testes, though they fail to influence estrogen production by the ovaries. Analyses of cell-specific loss- and gain-of-function models reveal that the osteoblast-derived hormone osteocalcin performs this endocrine function. By binding to a G protein-coupled receptor expressed in the Leydig cells of the testes, osteocalcin regulates in a CREB-dependent manner the expression of enzymes that is required for testosterone synthesis, promoting germ cell survival. This study expands the physiological repertoire of osteocalcin and provides the first evidence that the skeleton is an endocrine regulator of reproduction.


Assuntos
Osso e Ossos/fisiologia , Fertilidade , Osteocalcina/fisiologia , Animais , Células Cultivadas , Humanos , Células Intersticiais do Testículo/fisiologia , Masculino , Camundongos , Osteoblastos/fisiologia , Testículo/fisiologia
3.
J Hepatol ; 80(2): 251-267, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36972796

RESUMO

BACKGROUND & AIMS: Chronic viral infections present serious public health challenges; however, direct-acting antivirals (DAAs) are now able to cure nearly all patients infected with hepatitis C virus (HCV), representing the only cure of a human chronic viral infection to date. DAAs provide a valuable opportunity to study immune pathways in the reversal of chronic immune failures in an in vivo human system. METHODS: To leverage this opportunity, we used plate-based single-cell RNA-seq to deeply profile myeloid cells from liver fine needle aspirates in patients with HCV before and after DAA treatment. We comprehensively characterised liver neutrophils, eosinophils, mast cells, conventional dendritic cells, plasmacytoid dendritic cells, classical monocytes, non-classical monocytes, and macrophages, and defined fine-grained subpopulations of several cell types. RESULTS: We discovered cell type-specific changes post-cure, including an increase in MCM7+STMN1+ proliferating CD1C+ conventional dendritic cells, which may support restoration from chronic exhaustion. We observed an expected downregulation of interferon-stimulated genes (ISGs) post-cure as well as an unexpected inverse relationship between pre-treatment viral load and post-cure ISG expression in each cell type, revealing a link between viral loads and sustained modifications of the host's immune system. We found an upregulation of PD-L1/L2 gene expression in ISG-high neutrophils and IDO1 expression in eosinophils, pinpointing cell subpopulations crucial for immune regulation. We identified three recurring gene programmes shared by multiple cell types, distilling core functions of the myeloid compartment. CONCLUSIONS: This comprehensive single-cell RNA-seq atlas of human liver myeloid cells in response to cure of chronic viral infections reveals principles of liver immunity and provides immunotherapeutic insights. CLINICAL TRIAL REGISTRATION: This study is registered at ClinicalTrials.gov (NCT02476617). IMPACT AND IMPLICATIONS: Chronic viral liver infections continue to be a major public health problem. Single-cell characterisation of liver immune cells during hepatitis C and post-cure provides unique insights into the architecture of liver immunity contributing to the resolution of the first curable chronic viral infection of humans. Multiple layers of innate immune regulation during chronic infections and persistent immune modifications after cure are revealed. Researchers and clinicians may leverage these findings to develop methods to optimise the post-cure environment for HCV and develop novel therapeutic approaches for other chronic viral infections.


Assuntos
Hepatite C Crônica , Hepatite C , Humanos , Antivirais/uso terapêutico , Infecção Persistente , Hepatite C/tratamento farmacológico , Hepacivirus/genética
4.
Mov Disord ; 39(1): 141-151, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37964426

RESUMO

BACKGROUND: The ITPR1 gene encodes the inositol 1,4,5-trisphosphate (IP3 ) receptor type 1 (IP3 R1), a critical player in cerebellar intracellular calcium signaling. Pathogenic missense variants in ITPR1 cause congenital spinocerebellar ataxia type 29 (SCA29), Gillespie syndrome (GLSP), and severe pontine/cerebellar hypoplasia. The pathophysiological basis of the different phenotypes is poorly understood. OBJECTIVES: We aimed to identify novel SCA29 and GLSP cases to define core phenotypes, describe the spectrum of missense variation across ITPR1, standardize the ITPR1 variant nomenclature, and investigate disease progression in relation to cerebellar atrophy. METHODS: Cases were identified using next-generation sequencing through the Deciphering Developmental Disorders study, the 100,000 Genomes project, and clinical collaborations. ITPR1 alternative splicing in the human cerebellum was investigated by quantitative polymerase chain reaction. RESULTS: We report the largest, multinational case series of 46 patients with 28 unique ITPR1 missense variants. Variants clustered in functional domains of the protein, especially in the N-terminal IP3 -binding domain, the carbonic anhydrase 8 (CA8)-binding region, and the C-terminal transmembrane channel domain. Variants outside these domains were of questionable clinical significance. Standardized transcript annotation, based on our ITPR1 transcript expression data, greatly facilitated analysis. Genotype-phenotype associations were highly variable. Importantly, while cerebellar atrophy was common, cerebellar volume loss did not correlate with symptom progression. CONCLUSIONS: This dataset represents the largest cohort of patients with ITPR1 missense variants, expanding the clinical spectrum of SCA29 and GLSP. Standardized transcript annotation is essential for future reporting. Our findings will aid in diagnostic interpretation in the clinic and guide selection of variants for preclinical studies. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Aniridia , Anidrases Carbônicas , Ataxia Cerebelar , Deficiência Intelectual , Transtornos dos Movimentos , Degenerações Espinocerebelares , Humanos , Ataxia Cerebelar/genética , Mutação de Sentido Incorreto/genética , Transtornos dos Movimentos/complicações , Atrofia , Receptores de Inositol 1,4,5-Trifosfato/química , Receptores de Inositol 1,4,5-Trifosfato/genética , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Anidrases Carbônicas/genética , Anidrases Carbônicas/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética
5.
Int J Mol Sci ; 25(4)2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38396999

RESUMO

Fibrosis is a chronic pathology resulting from excessive deposition of extracellular matrix components that leads to the loss of tissue function. Pulmonary fibrosis can follow a variety of diverse insults including ischemia, respiratory infection, or exposure to ionizing radiation. Consequently, treatments that attenuate the development of debilitating fibrosis are in desperate need across a range of conditions. Sphingolipid metabolism is a critical regulator of cell proliferation, apoptosis, autophagy, and pathologic inflammation, processes that are all involved in fibrosis. Opaganib (formerly ABC294640) is the first-in-class investigational drug targeting sphingolipid metabolism for the treatment of cancer and inflammatory diseases. Opaganib inhibits key enzymes in sphingolipid metabolism, including sphingosine kinase-2 and dihydroceramide desaturase, thereby reducing inflammation and promoting autophagy. Herein, we demonstrate in mouse models of lung damage following exposure to ionizing radiation that opaganib significantly improved long-term survival associated with reduced lung fibrosis, suppression of granulocyte infiltration, and reduced expression of IL-6 and TNFα at 180 days after radiation. These data further demonstrate that sphingolipid metabolism is a critical regulator of fibrogenesis, and specifically show that opaganib suppresses radiation-induced pulmonary inflammation and fibrosis. Because opaganib has demonstrated an excellent safety profile during clinical testing in other diseases (cancer and COVID-19), the present studies support additional clinical trials with this drug in patients at risk for pulmonary fibrosis.


Assuntos
Adamantano/análogos & derivados , Contramedidas Médicas , Neoplasias , Pneumonia , Fibrose Pulmonar , Piridinas , Camundongos , Animais , Humanos , Esfingolipídeos/metabolismo , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/etiologia , Fibrose Pulmonar/patologia , Fibrose , Inflamação/tratamento farmacológico
6.
Ann Hematol ; 102(2): 369-383, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36460794

RESUMO

Multiple myeloma (MM) remains an incurable disease and there is an unmet medical need for novel therapeutic drugs that do not share similar mechanisms of action with currently available agents. Sphingosine kinase 2 (SK2) is an innovative molecular target for anticancer therapy. We previously reported that treatment with SK2 inhibitor opaganib inhibited myeloma tumor growth in vitro and in vivo in a mouse xenograft model. In the current study, we performed a phase I study of opaganib in patients with relapsed/refractory multiple myeloma (RRMM). Thirteen patients with RRMM previously treated with immunomodulatory agents and proteasome inhibitors were enrolled and treated with single-agent opaganib at three oral dosing regimens (250 mg BID, 500 mg BID, or 750 mg BID, 28 days as a cycle). Safety and maximal tolerated dose (MTD) were determined. Pharmacokinetics, pharmacodynamics, and correlative studies were also performed. Opaganib was well tolerated up to a dose of 750 mg BID. The most common possibly related adverse event (AE) was decreased neutrophil counts. There were no serious AEs considered to be related to opaganib. MTD was determined as at least 750 mg BID. On an intent-to-treat basis, one patient (7.7%) in the 500 mg BID dose cohort showed a very good partial response, and one other patient (7.7%) achieved stable disease for 3 months. SK2 is an innovative molecular target for antimyeloma therapy. The first-in-class SK2 inhibitor opaganib is generally safe for administration to RRMM patients, and has potential therapeutic activity in these patients. Clinicaltrials.gov: NCT02757326.


Assuntos
Mieloma Múltiplo , Humanos , Animais , Camundongos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/patologia , Fosfotransferases (Aceptor do Grupo Álcool)/uso terapêutico , Inibidores de Proteassoma/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Dexametasona
7.
Nano Lett ; 22(20): 8045-8051, 2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36194549

RESUMO

We have synthesized the first reported example of quantum confined high-entropy (HE) nanoparticles, using the lanthanide oxysulfide, Ln2SO2, system as the host phase for an equimolar mixture of Pr, Nd, Gd, Dy, and Er. A uniform HE phase was achieved via the simultaneous thermolysis of a mixture of lanthanide dithiocarbamate precursors in solution. This was confirmed by powder X-ray diffraction and high-resolution scanning transmission electron microscopy, with energy dispersive X-ray spectroscopic mapping confirming the uniform distribution of the lanthanides throughout the particles. The nanoparticle dispersion displayed a significant blue shift in the absorption and photoluminescence spectra relative to our previously reported bulk sample with the same composition, with an absorption edge at 330 nm and a λmax at 410 nm compared to the absorption edge at 500 nm and a λmax at 450 nm in the bulk, which is indicative of quantum confinement. We support this postulate with experimental and theoretical analysis of the bandgap energy as a function of strain and surface effects (ligand binding) as well as calculation of the exciton Bohr radiii of the end member compounds.

8.
Int J Mol Sci ; 24(23)2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38069222

RESUMO

Antibody-based cancer drugs that target the checkpoint proteins CTLA-4, PD-1 and PD-L1 provide marked improvement in some patients with deadly diseases such as lung cancer and melanoma. However, most patients are either unresponsive or relapse following an initial response, underscoring the need for further improvement in immunotherapy. Certain drugs induce immunogenic cell death (ICD) in tumor cells in which the dying cells promote immunologic responses in the host that may enhance the in vivo activity of checkpoint antibodies. Sphingolipid metabolism is a key pathway in cancer biology, in which ceramides and sphingosine 1-phosphate (S1P) regulate tumor cell death, proliferation and drug resistance, as well as host inflammation and immunity. In particular, sphingosine kinases are key sites for manipulation of the ceramide/S1P balance that regulates tumor cell proliferation and sensitivity to radiation and chemotherapy. We and others have demonstrated that inhibition of sphingosine kinase-2 by the small-molecule investigational drug opaganib (formerly ABC294640) kills tumor cells and increases their sensitivities to other drugs and radiation. Because sphingolipids have been shown to regulate ICD, opaganib may induce ICD and improve the efficacy of checkpoint antibodies for cancer therapy. This was demonstrated by showing that in vitro treatment with opaganib increases the surface expression of the ICD marker calreticulin on a variety of tumor cell types. In vivo confirmation was achieved using the gold standard immunization assay in which B16 melanoma, Lewis lung carcinoma (LLC) or Neuro-2a neuroblastoma cells were treated with opaganib in vitro and then injected subcutaneously into syngeneic mice, followed by implantation of untreated tumor cells 7 days later. In all cases, immunization with opaganib-treated cells strongly suppressed the growth of subsequently injected tumor cells. Interestingly, opaganib treatment induced crossover immunity in that opaganib-treated B16 cells suppressed the growth of both untreated B16 and LLC cells and opaganib-treated LLC cells inhibited the growth of both untreated LLC and B16 cells. Next, the effects of opaganib in combination with a checkpoint antibody on tumor growth in vivo were assessed. Opaganib and anti-PD-1 antibody each slowed the growth of B16 tumors and improved mouse survival, while the combination of opaganib plus anti-PD-1 strongly suppressed tumor growth and improved survival (p < 0.0001). Individually, opaganib and anti-CTLA-4 antibody had modest effects on the growth of LLC tumors and mouse survival, whereas the combination of opaganib with anti-CTLA-4 substantially inhibited tumor growth and increased survival (p < 0.001). Finally, the survival of mice bearing B16 tumors was only marginally improved by opaganib or anti-PD-L1 antibody alone but was nearly doubled by the drugs in combination (p < 0.005). Overall, these studies demonstrate the ability of opaganib to induce ICD in tumor cells, which improves the antitumor activity of checkpoint antibodies.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Lewis , Melanoma Experimental , Humanos , Animais , Camundongos , Morte Celular Imunogênica , Antineoplásicos/uso terapêutico , Piridinas , Melanoma Experimental/tratamento farmacológico , Carcinoma Pulmonar de Lewis/tratamento farmacológico , Linhagem Celular Tumoral
9.
Am J Hum Genet ; 104(5): 914-924, 2019 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-30982611

RESUMO

Glypicans are a family of cell-surface heparan sulfate proteoglycans that regulate growth-factor signaling during development and are thought to play a role in the regulation of morphogenesis. Whole-exome sequencing of the Australian family that defined Keipert syndrome (nasodigitoacoustic syndrome) identified a hemizygous truncating variant in the gene encoding glypican 4 (GPC4). This variant, located in the final exon of GPC4, results in premature termination of the protein 51 amino acid residues prior to the stop codon, and in concomitant loss of functionally important N-linked glycosylation (Asn514) and glycosylphosphatidylinositol (GPI) anchor (Ser529) sites. We subsequently identified seven affected males from five additional kindreds with novel and predicted pathogenic variants in GPC4. Segregation analysis and X-inactivation studies in carrier females provided supportive evidence that the GPC4 variants caused the condition. Furthermore, functional studies of recombinant protein suggested that the truncated proteins p.Gln506∗ and p.Glu496∗ were less stable than the wild type. Clinical features of Keipert syndrome included a prominent forehead, a flat midface, hypertelorism, a broad nose, downturned corners of mouth, and digital abnormalities, whereas cognitive impairment and deafness were variable features. Studies of Gpc4 knockout mice showed evidence of the two primary features of Keipert syndrome: craniofacial abnormalities and digital abnormalities. Phylogenetic analysis demonstrated that GPC4 is most closely related to GPC6, which is associated with a bone dysplasia that has a phenotypic overlap with Keipert syndrome. Overall, we have shown that pathogenic variants in GPC4 cause a loss of function that results in Keipert syndrome, making GPC4 the third human glypican to be linked to a genetic syndrome.


Assuntos
Surdez/congênito , Doenças Genéticas Ligadas ao Cromossomo X/genética , Doenças Genéticas Ligadas ao Cromossomo X/patologia , Variação Genética , Glipicanas/genética , Deformidades Congênitas das Extremidades Inferiores/genética , Deformidades Congênitas das Extremidades Inferiores/patologia , Adulto , Criança , Pré-Escolar , Surdez/genética , Surdez/patologia , Feminino , Humanos , Lactente , Masculino , Linhagem , Fenótipo , Adulto Jovem
10.
Pediatr Blood Cancer ; 69(5): e29618, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35195344

RESUMO

BACKGROUND: During pediatric hematopoietic stem cell transplant (HSCT), there is significant reduction in physical activity, leading to loss of strength and function, along with decline in quality of life (QoL). This study evaluates the effects of a supervised exercise program on functional ability, mobility, strength, and QoL during and following pediatric HSCT. METHODS: Patients ages 4-21 years presenting for HSCT were randomized to either an intervention group, who underwent exercise routines three times weekly and once weekly on discharge for 6 weeks supervised by a physical therapist, or the control group, which was treated per standard of care. Forty subjects were recruited for the study, 20 in each arm. Physical therapy and QoL assessments were conducted at three time points: pre-HSCT (baseline), on the day of hospital discharge, and 6 weeks after discharge. RESULTS: Exercise capacity and endurance using Six-Minute Walk test (p = .023) and strength using manual muscle testing (p = .005) were improved in the exercise group, compared to the control group. There was evidence that some QoL outcomes (measured using the Patient Reported Outcomes Measurement Information System) were improved 6 weeks post discharge, with observed decreases in anxiety (p = .0009) and fatigue (p = .037). CONCLUSION: Supervised exercise program during pediatric HSCT has positive effects on endurance, functional mobility, and muscle strength, and may also result in improvements in some aspects of QoL. This trial was registered at www. CLINICALTRIALS: gov as NCT04663503.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Qualidade de Vida , Adolescente , Adulto , Assistência ao Convalescente , Criança , Pré-Escolar , Exercício Físico , Terapia por Exercício , Humanos , Alta do Paciente , Transplante de Células-Tronco , Adulto Jovem
11.
Int J Mol Sci ; 23(21)2022 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-36361977

RESUMO

Exposure to ionizing radiation (IR) is a lingering threat from accidental or terroristic nuclear events, but is also widely used in cancer therapy. In both cases, host inflammatory responses to IR damage normal tissue causing morbidity and possibly mortality to the victim/patient. Opaganib, a first-in-class inhibitor of sphingolipid metabolism, has broad anti-inflammatory and anticancer activity. Opaganib elevates ceramide and reduces sphingosine 1-phosphate (S1P) in cells, conditions that increase the antitumor efficacy of radiation while concomitantly suppressing inflammatory damage to normal tissue. Therefore, opaganib may suppress toxicity from unintended IR exposure and improve patient response to chemoradiation. To test these hypotheses, we first examined the effects of opaganib on the toxicity and antitumor activity of radiation in mice exposed to total body irradiation (TBI) or IR with partial bone marrow shielding. Oral treatment with opaganib 2 h before TBI shifted the LD75 from 9.5 Gy to 11.5 Gy, and provided substantial protection against gastrointestinal damage associated with suppression of radiation-induced elevations of S1P and TNFα in the small intestines. In the partially shielded model, opaganib provided dose-dependent survival advantages when administered 4 h before or 24 h after radiation exposure, and was particularly effective when given both prior to and following radiation. Relevant to cancer radiotherapy, opaganib decreased the sensitivity of IEC6 (non-transformed mouse intestinal epithelial) cells to radiation, while sensitizing PAN02 cells to in vitro radiation. Next, the in vivo effects of opaganib in combination with radiation were examined in a syngeneic tumor model consisting of C57BL/6 mice bearing xenografts of PAN02 pancreatic cancer cells and a cross-species xenograft model consisting of nude mice bearing xenografts of human FaDu cells. Mice were treated with opaganib and/or IR (plus cisplatin in the case of FaDu tumors). In both tumor models, the optimal suppression of tumor growth was attained by the combination of opaganib with IR (± cisplatin). Overall, opaganib substantially protects normal tissue from radiation damage that may occur through unintended exposure or cancer radiotherapy.


Assuntos
Cisplatino , Neoplasias , Humanos , Camundongos , Animais , Camundongos Nus , Camundongos Endogâmicos C57BL , Linhagem Celular Tumoral
12.
J Int Relat Dev (Ljubl) ; 25(4): 1046-1077, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36105182

RESUMO

Most scholarship on major oil-producing countries (OPCs) focuses on their illiberal characteristics, but scant research explores how these regimes react to periodic oil price collapses, particularly neo-patrimonial OPCs with relatively low state capacity, herein termed gatekeeper OPCs. These OPCs should be extremely vulnerable to regime change during economic crises. However, since the most recent collapse in international oil markets in 2014, almost all neo-patrimonial OPCs have managed to weather the ensuing fallout, thereby begging the question of how these seemingly vulnerable regimes manage to survive extended periods of economic crises. We hypothesise that the likelihood of regime survival in neo-patrimonial OPCs depends on a strategic calibration of domestic neo-patrimonial policies, such as clientelism and executive aggrandisement, and the skilled navigation of global geopolitics. We find evidence that incumbent governments leverage international geopolitical tensions during economic crises to secure valuable foreign aid from key allies, which allows them to maintain the domestic neo-patrimonial strategies required to safeguard their power. We reached the above finding through a nested mixed-methods research design combining quantitative analysis of 35 major OPCs from 2011 to 2018 using Cox proportional hazards models with the qualitative comparison of two gatekeeper OPCs-Chad and Venezuela.

13.
J Struct Biol ; 213(4): 107805, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34715329

RESUMO

The revolution in genetics has rapidly increased our knowledge of human and mouse genes that are critical for the formation of dental enamel and helps us understand how enamel evolved. In this graphical review we focus on the roles of 41 genes that are essential for the secretory stage of amelogenesis when characteristic enamel mineral ribbons initiate on dentin and elongate to expand the enamel layer to the future surface of the tooth. Based upon ultrastructural analyses of genetically modified mice, we propose a molecular model explaining how a cell attachment apparatus including collagen 17, α6ß4 and αvß6 integrins, laminin 332, and secreted enamel proteins could attach to individual enamel mineral ribbons and mold their cross-sectional dimensions as they simultaneously elongate and orient them in the direction of the retrograde movement of the ameloblast membrane.


Assuntos
Ameloblastos/metabolismo , Amelogênese/genética , Proteínas do Esmalte Dentário/genética , Esmalte Dentário/metabolismo , Modelos Genéticos , Ameloblastos/citologia , Ameloblastos/ultraestrutura , Animais , Colágeno/genética , Colágeno/metabolismo , Esmalte Dentário/citologia , Proteínas do Esmalte Dentário/metabolismo , Humanos , Integrinas/genética , Integrinas/metabolismo , Laminina/genética , Laminina/metabolismo , Camundongos , Microscopia Eletrônica de Varredura/métodos
14.
J Am Chem Soc ; 143(51): 21560-21566, 2021 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-34923815

RESUMO

High entropy (HE) materials have received significant attention in recent years, due to their intrinsically high levels of configurational entropy. While there has been significant work exploring HE alloys and oxides, new families of HE materials are still being revealed. In this work we present the synthesis of a novel family of HE materials based on lanthanide oxysulfides. Here, we implement lanthanide dithiocarbamates as versatile precursors that can be mixed at the molecular scale prior to thermolysis in order to produce the high entropy oxysulfide. The target of our synthesis is the HE Ln2SO2 phase, where Ln = Pr, Nd, Gd, Dy, Er and where Ln = Pr, Nd, Gd, Dy for 5 and 4 lanthanide samples, respectively. We confirmed the structure of samples produced by powder X-ray diffraction, electron microscopy, and high-resolution energy dispersive X-ray spectroscopy. Optical spectroscopy shows a broad emission feature centered around 450 nm as well as a peak in absorption at around 280 nm. From this data we calculate the band gap and Urbach energies of the materials produced.

15.
Am J Hum Genet ; 102(1): 116-132, 2018 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-29290337

RESUMO

Whole-exome and targeted sequencing of 13 individuals from 10 unrelated families with overlapping clinical manifestations identified loss-of-function and missense variants in KIAA1109 allowing delineation of an autosomal-recessive multi-system syndrome, which we suggest to name Alkuraya-Kucinskas syndrome (MIM 617822). Shared phenotypic features representing the cardinal characteristics of this syndrome combine brain atrophy with clubfoot and arthrogryposis. Affected individuals present with cerebral parenchymal underdevelopment, ranging from major cerebral parenchymal thinning with lissencephalic aspect to moderate parenchymal rarefaction, severe to mild ventriculomegaly, cerebellar hypoplasia with brainstem dysgenesis, and cardiac and ophthalmologic anomalies, such as microphthalmia and cataract. Severe loss-of-function cases were incompatible with life, whereas those individuals with milder missense variants presented with severe global developmental delay, syndactyly of 2nd and 3rd toes, and severe muscle hypotonia resulting in incapacity to stand without support. Consistent with a causative role for KIAA1109 loss-of-function/hypomorphic variants in this syndrome, knockdowns of the zebrafish orthologous gene resulted in embryos with hydrocephaly and abnormally curved notochords and overall body shape, whereas published knockouts of the fruit fly and mouse orthologous genes resulted in lethality or severe neurological defects reminiscent of the probands' features.


Assuntos
Artrogripose/genética , Encéfalo/embriologia , Mutação/genética , Proteínas/genética , Adolescente , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Criança , Feminino , Técnicas de Silenciamento de Genes , Humanos , Lactente , Recém-Nascido , Imageamento por Ressonância Magnética , Masculino , Linhagem , Peixe-Zebra , Proteínas de Peixe-Zebra/genética
16.
J Pediatr ; 235: 63-74.e12, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33894262

RESUMO

OBJECTIVE: To assess the eligibility criteria and trial characteristics among contemporary (2010-2019) randomized clinical trials (RCTs) that included infants born extremely preterm (<28 weeks of gestation) and to evaluate whether eligibility criteria result in underrepresentation of high-risk subgroups (eg, infants born at <24 weeks of gestation). STUDY DESIGN: PubMed and Scopus were searched January 1, 2010, to December 31, 2019, with no language restrictions. RCTs with mean or median gestational ages at birth of <28 weeks of gestation were included. The study followed the PRISMA guidelines; outcomes were registered prospectively. Data extraction was performed independently by multiple observers. Study quality was evaluated using a modified Jadad scale. RESULTS: Among RCTs (n = 201), 32 552 infants were included. Study participant characteristics, interventions, and outcomes were highly variable. A total of 1603 eligibility criteria were identified; rationales were provided for 18.8% (n = 301) of criteria. Fifty-five RCTs (27.4%) included infants <24 weeks of gestation; 454 (1.4%) infants were identified as <24 weeks of gestation. CONCLUSIONS: The present study identifies sources of variability across RCTs that included infants born extremely preterm and reinforces the critical need for consistent and transparent policies governing eligibility criteria.


Assuntos
Lactente Extremamente Prematuro , Seleção de Pacientes , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Recém-Nascido
17.
Bioconjug Chem ; 32(7): 1290-1297, 2021 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-33434428

RESUMO

We report herein the preclinical evaluation of new [64Cu]Cu-gastrin-releasing peptide receptor (GRPR)-targeting tracers, employing the potent peptide antagonist DPhe-Gln-Trp-Ala-VaI-Gly-His-Sta-Leu-NH2 conjugated to NOTA (in 1) or NODAGA (in 2) chelators via a 6-aminohexanoic acid linker. The Cu-1/2 metalated peptides were synthesized by reacting 1/2 with CuCl2 and were characterized by LC-ESI-MS and HR-ESI-MS. Cu-1/2 exhibited high GRPR-binding affinities with IC50 values <3 nM, as measured in a competition assay using the GRPR-expressing human PC-3 prostate cancer cell line and [125I]I-Tyr4-BBN as the competing ligand. Tracers [64Cu]Cu-1/2 were prepared in quantitative radiochemical yield (by radio-HPLC), and their identities were confirmed by coelution with their Cu-1/2 standards via comparative HPLC studies. Lipophilicity was measured in 1-octanol/PBS (pH 7.4), and the negative log D7.4 values (≤-1) confirmed the anticipated hydrophilic character for [64Cu]Cu-1/2. Both tracers demonstrated excellent in vitro stability, with ≥98% remaining intact through 24 h at physiological conditions (PBS, pH 7.4, 37 °C). Biodistribution in PC-3 tumor-bearing mice demonstrated good tumor uptake (%ID/g at 4 h: 4.34 ± 0.71 for [64Cu]Cu-1, 3.92 ± 1.03 for [64Cu]Cu-2) and rapid renal clearance (≥87% ID at 4 h). Tumor uptake was receptor-mediated, as verified by parallel GRPR-blocking studies. Small-animal PET/CT imaging studies validated the biodistribution data. These preclinical data support that the [64Cu]Cu-1/2 tracers show promise for further development as diagnostic PET imaging agents of GRPR-expressing tumors.


Assuntos
Radioisótopos de Cobre/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Neoplasias da Próstata/diagnóstico por imagem , Receptores da Bombesina/metabolismo , Animais , Humanos , Masculino , Receptores da Bombesina/química
18.
J Anat ; 238(4): 970-985, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33145767

RESUMO

Focal stacks are an alternative spatial arrangement of enamel rods within the inner enamel of mandibular mouse incisors where short rows comprised of 2-45 enamel rods are nestled at the side of much longer rows, both sharing the same rod tilt directed mesially or laterally. The significance of focal stacks to enamel function is unknown, but their high frequency in transverse sections (30% of all rows) suggests that they serve some purpose beyond representing an oddity of enamel development. In this study, we characterized the spatial distribution of focal stacks in random transverse sections relative to different regions of the inner enamel and to different locations across enamel thickness. The curving dentinoenamel junction (DEJ) in transverse sections complicated spatial distribution analyses, and a technique was developed to "unbend" the curving DEJ allowing for more linear quantitative analyses to be carried out. The data indicated that on average there were 36 ± 7 focal stacks located variably within the inner enamel in any given transverse section. Consistent with area distributions, focal stacks were four times more frequent in the lateral region (53%) and twice as frequent in the mesial region (33%) compared to the central region (14%). Focal stacks were equally split by tilt (52% mesial vs. 48% lateral, not significant), but those having a mesial tilt were more frequently encountered in the lateral and central regions (2:1) and those having a lateral tilt were more numerous in the mesial region (1:3). Focal stacks having a mesial tilt were longer on average compared to those having a lateral tilt (7.5 ± 5.6 vs. 5.9 ± 4.0 rods per row, p < 0.01). There was no relationship between the length of a focal stack and its location within the inner enamel. All results were consistent with the notion that focal stacks travel from the DEJ to the outer enamel the same as the longer and decussating companion rows to which they are paired. The spatial distribution of focal stacks within the inner enamel was not spatially random but best fit a null model based on a heterogenous Poisson point process dependent on regional location within the transverse plane of the enamel layer.


Assuntos
Esmalte Dentário/ultraestrutura , Incisivo/ultraestrutura , Camundongos/anatomia & histologia , Animais , Mandíbula
19.
Am J Obstet Gynecol ; 224(2): 158-174, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32745459

RESUMO

OBJECTIVE: The objective of this study was to provide a systematic review and meta-analysis to quantify prognosis and identify factors associated with variations in reported mortality estimates among infants who were born at 22 weeks of gestation and provided proactive treatment (resuscitation and intensive care). DATA SOURCES: PubMed, Scopus, and Web of Science databases, with no language restrictions, were searched for articles published from January 2000 to February 2020. STUDY ELIGIBILITY CRITERIA: Reports on live-born infants who were delivered at 22 weeks of gestation and provided proactive care were included. The primary outcome was survival to hospital discharge; secondary outcomes included survival without major morbidity and survival without neurodevelopmental impairment. Because we expected differences across studies in the definitions for various morbidities, multiple definitions for composite outcomes of major morbidities were prespecified. Neurodevelopmental impairment was based on Bayley Scales of Infant Development II or III. Data extractions were performed independently, and outcomes agreed on a priori. STUDY APPRAISAL AND SYNTHESIS METHODS: Methodological quality was assessed using the Quality in Prognostic Studies tool. An adapted version of the Grading of Recommendations Assessment, Development and Evaluation approach for prognostic studies was used to evaluate confidence in overall estimates. Outcomes were assessed as prevalence and 95% confidence intervals. Variabilities across studies attributable to heterogeneity were estimated with the I2 statistic; publication bias was assessed with the Luis Furuya-Kanamori index. Data were pooled using the inverse variance heterogeneity model. RESULTS: Literature searches returned 21,952 articles, with 2034 considered in full; 31 studies of 2226 infants who were delivered at 22 weeks of gestation and provided proactive neonatal treatment were included. No articles were excluded for study design or risk of bias. The pooled prevalence of survival was 29.0% (95% confidence interval, 17.2-41.6; 31 studies, 2226 infants; I2=79.4%; Luis Furuya-Kanamori index=0.04). Survival among infants born to mothers receiving antenatal corticosteroids was twice the survival of infants born to mothers not receiving antenatal corticosteroids (39.0% vs 19.5%; P<.01). The overall prevalence of survival without major morbidity, using a definition that includes any bronchopulmonary dysplasia, was 11.0% (95% confidence interval, 8.0-14.3; 10 studies, 374 infants; I2=0%; Luis Furuya-Kanamori index=3.02). The overall rate of survival without moderate or severe impairment was 37.0% (95% confidence interval, 14.6-61.5; 5 studies, 39 infants; I2=45%; Luis Furuya-Kanamori index=-0.15). Based on the year of publication, survival rates increased between 2000 and 2020 (slope of the regression line=0.09; standard error=0.03; P<.01). Studies were highly diverse with regard to interventions and outcomes reported. CONCLUSION: The reported survival rates varied greatly among studies and were likely influenced by combining observational data from disparate sources, lack of individual patient-level data, and bias in the component studies from which the data were drawn. Therefore, pooled results should be interpreted with caution. To answer fundamental questions beyond the breadth of available data, multicenter, multidisciplinary collaborations, including alignment of important outcomes by stakeholders, are needed.


Assuntos
Idade Gestacional , Terapia Intensiva Neonatal , Ressuscitação , Taxa de Sobrevida , Corticosteroides/uso terapêutico , Displasia Broncopulmonar/epidemiologia , Hemorragia Cerebral Intraventricular/epidemiologia , Enterocolite Necrosante/epidemiologia , Viabilidade Fetal , Humanos , Lactente Extremamente Prematuro , Recém-Nascido , Leucomalácia Periventricular/epidemiologia , Transtornos do Neurodesenvolvimento/epidemiologia , Cuidado Pré-Natal , Retinopatia da Prematuridade/epidemiologia , Índice de Gravidade de Doença
20.
J Strength Cond Res ; 35(3): 804-810, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30234694

RESUMO

ABSTRACT: Zanders, BR, Currier, BS, Harty, PS, Zabriskie, HA, Smith, CR, Stecker, RA, Richmond, SR, Jagim, AR, and Kerksick, CM. Changes in energy expenditure, dietary intake, and energy availability across an entire collegiate women's basketball season. J Strength Cond Res 35(3): 804-810, 2021-The purpose of this study was to identify changes in energy expenditure and dietary intake across an entire women's basketball season. On 5 different occasions across the competitive season, female collegiate basketball players (19.8 ± 1.3 years, 173.9 ± 13.6 cm, 74.6 ± 9.1 kg, 27.1 ± 3.2% fat, 53.9 ± 6.4 ml·kg-1·min-1, n = 13) were outfitted with heart rate and activity monitors over 4 consecutive days and completed 4-day food and fluid records to assess changes in energy expenditure and dietary status. Dual-energy x-ray absorptiometry was used to assess baseline body composition and resting energy expenditure (REE) was measured before and after the season. Data were analyzed using 1-factor repeated-measures analysis of variance. Total daily energy expenditure (TDEE, p = 0.059) and physical activity levels (TDEE/REE, p = 0.060) both tended to decrease throughout the season. Energy balance was negative at all time points throughout the season. Absolute and normalized daily protein intake at the end of the season was significantly (p < 0.05) lower than at the beginning of the season. Carbohydrate (3.7 ± 0.4 g·kg-1·d-1) and protein (1.17 ± 0.16 g·kg-1·d-1) intakes were lower than commonly recommended values based on previously published guidelines. These findings suggest that greater education and interventions for collegiate athletes and coaches regarding dietary intake and energy expenditure are warranted.


Assuntos
Basquetebol , Composição Corporal , Ingestão de Alimentos , Ingestão de Energia , Metabolismo Energético , Feminino , Humanos , Estações do Ano
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