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1.
Cell ; 187(7): 1801-1818.e20, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38471500

RESUMO

The repertoire of modifications to bile acids and related steroidal lipids by host and microbial metabolism remains incompletely characterized. To address this knowledge gap, we created a reusable resource of tandem mass spectrometry (MS/MS) spectra by filtering 1.2 billion publicly available MS/MS spectra for bile-acid-selective ion patterns. Thousands of modifications are distributed throughout animal and human bodies as well as microbial cultures. We employed this MS/MS library to identify polyamine bile amidates, prevalent in carnivores. They are present in humans, and their levels alter with a diet change from a Mediterranean to a typical American diet. This work highlights the existence of many more bile acid modifications than previously recognized and the value of leveraging public large-scale untargeted metabolomics data to discover metabolites. The availability of a modification-centric bile acid MS/MS library will inform future studies investigating bile acid roles in health and disease.


Assuntos
Ácidos e Sais Biliares , Microbioma Gastrointestinal , Metabolômica , Espectrometria de Massas em Tandem , Animais , Humanos , Ácidos e Sais Biliares/química , Metabolômica/métodos , Poliaminas , Espectrometria de Massas em Tandem/métodos , Bases de Dados de Compostos Químicos
2.
J Biol Chem ; 300(8): 107559, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-39002679

RESUMO

Many anaerobic microorganisms use the bifunctional aldehyde and alcohol dehydrogenase enzyme, AdhE, to produce ethanol. One such organism is Clostridium thermocellum, which is of interest for cellulosic biofuel production. In the course of engineering this organism for improved ethanol tolerance and production, we observed that AdhE was a frequent target of mutations. Here, we characterized those mutations to understand their effects on enzymatic activity, as well ethanol tolerance and product formation in the organism. We found that there is a strong correlation between NADH-linked alcohol dehydrogenase (ADH) activity and ethanol tolerance. Mutations that decrease NADH-linked ADH activity increase ethanol tolerance; correspondingly, mutations that increase NADH-linked ADH activity decrease ethanol tolerance. We also found that the magnitude of ADH activity did not play a significant role in determining ethanol titer. Increasing ADH activity had no effect on ethanol titer. Reducing ADH activity had indeterminate effects on ethanol titer, sometimes increasing and sometimes decreasing it. Finally, this study shows that the cofactor specificity of ADH activity was found to be the primary factor affecting ethanol yield. We expect that these results will inform efforts to use AdhE enzymes in metabolic engineering approaches.

3.
J Hum Evol ; 187: 103490, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38266614

RESUMO

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.


Assuntos
Hominidae , Dente , Humanos , Animais , Fósseis , Deriva Genética , Dente Molar , Dente Decíduo
4.
Artigo em Inglês | MEDLINE | ID: mdl-38259170

RESUMO

A bacterial strain, designated NLS-7T, was isolated through enrichment of landfill cover soil in methane-oxidizing conditions. Strain NLS-7T is a Gram-stain negative, non-motile rod, approximately 0.8 µm wide by 1.3 µm long. Phylogenetic analysis based on 16S rRNA gene sequencing places it within the genus Methylocystis, with its closest relatives being M. hirsuta, M. silviterrae and M. rosea, with 99.9, 99.7 and 99.6 % sequence similarity respectively. However, average nucleotide identity and average amino acid identity values below the 95 % threshold compared to all the close relatives and digital DNA-DNA hybridization values between 20.9 and 54.1 % demonstrate that strain NLS-7T represents a novel species. Genome sequencing generated 4.31 million reads and genome assembly resulted in the generation of 244 contigs with a total assembly length of 3 820 957 bp (N50, 37 735 bp; L50, 34). Genome completeness is 99.5 % with 3.98 % contamination. It is capable of growth on methane and methanol. It grows optimally at 30 °C between pH 6.5 and 7.0. Strain NLS-7T is capable of atmospheric dinitrogen fixation and can use ammonium (as NH4Cl), l-aspartate, l-arginine, yeast extract, nitrate, l-leucine, l-proline, l-methionine, l-lysine and l-alanine as nitrogen sources. The major fatty acids are C18:1 ω8c and C18:1 ω7c. Based upon this polyphasic taxonomic study, strain NLS-7T represents a novel species of the genus Methylocystis, for which the name Methylocystis suflitae sp. nov. is proposed. The type strain is NLS-7T (=ATCC TSD-256T=DSM 112294T). The 16S rRNA gene and genome sequences of strain NLS-7T have been deposited in GenBank under accession numbers ON715489 and GCA_024448135.1, respectively.


Assuntos
Methylocystaceae , Methylocystaceae/genética , Ácidos Graxos/química , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Composição de Bases , Bactérias , Metano
5.
Ann Hum Biol ; 51(1): 2321128, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38509686

RESUMO

BACKGROUND: Six Homo naledi early juveniles were recovered from U.W. 101 (Dinaledi Chamber), U.W. 102 (Lesedi Chamber), and U.W. 110 in the Rising Star cave system. AIM: This paper develops the information for the H. naledi early juvenile life stage, as defined by a combination of deciduous and permanent dentition, and the eruption of the first permanent molar. SUBJECTS AND METHODS: The growing number of young individuals recovered from the Rising Star cave system allows us to gain a better understanding of their variation, or lack thereof, and provides a basis to estimate broad ranges for age at death of the individuals. The individuals are identified and described through craniodental remains and spatial associations. RESULTS AND CONCLUSION: Our results show that the teeth are remarkably consistent across the localities in their metric and non-metric traits, and our analyses refine previous estimations on dental eruptions with the first permanent molar erupting first in the sequence among permanent teeth.


Assuntos
Hominidae , Dente , Animais , Humanos , África do Sul , Fósseis , Fenótipo
6.
J Surg Orthop Adv ; 33(1): 29-32, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38815075

RESUMO

Bracing reduces the need for surgical intervention in patients with adolescent idiopathic scoliosis (AIS). However, bracing outcomes with variable body mass index (BMI) are understudied. The authors sought to determine the association of BMI with bracing outcomes. The authors performed a retrospective cohort study of 104 patients presenting with AIS. Initial Risser score, hours of bracing per day, BMI percentile, and curve magnitude pre- and postbracing were collected. There was no detectable difference between years of brace wear or primary curve magnitude at time of presentation between both groups. Overall, 29% (25/87) of underweight/normal weight patients and 59% (10/17) of overweight/obese patients had curves ≥ 45 degrees at the end of bracing (p = 0.016). Odds of having a curve ≥ 45 degrees after bracing were 3.5 (95% confidence interval: 1.2 to 10.3, p = 0.021) times higher for overweight/obese patients compared with underweight/normal weight patients. Increased overlying adipose tissue may reduce the corrective forces required to straighten the spine. (Journal of Surgical Orthopaedic Advances 33(1):029-032, 2024).


Assuntos
Índice de Massa Corporal , Braquetes , Escoliose , Humanos , Adolescente , Estudos Retrospectivos , Feminino , Masculino , Criança , Resultado do Tratamento , Sobrepeso/complicações , Magreza , Obesidade/complicações
7.
Curr Sports Med Rep ; 23(8): 277-279, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39102581

RESUMO

ABSTRACT: As physical therapists and exercise professionals, we have an obligation to promote health and well-being through participation in sport and recreational/physical activity. We play an active role in facilitating and encouraging movement for a large percentage of the population, including our transgender patients/clients. It is integral that we include transgender individuals in supportive and inclusive atmospheres of play, and it is critical for us to lead the conversation around the inclusion of the transgender community in recreational activities and sport. This commentary provides evidence for the physical therapy community to support, advocate for, and include all populations as we promote healthy habits through sport.


Assuntos
Medo , Esportes , Pessoas Transgênero , Humanos , Pessoas Transgênero/psicologia , Feminino , Masculino , Atletas/psicologia , Promoção da Saúde
12.
Taiwan J Obstet Gynecol ; 63(2): 242-244, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38485323

RESUMO

OBJECTIVE: Recurrent disseminated coccidioidal meningitis in two subsequent pregnancies is rare and can pose a challenge in ensuring the health of both mother and baby. In this unique case we highlight this rare occurrence and subsequent treatment. CASE REPORT: A 29-year-old G4P1021 with a history of disseminated coccidioidomycosis in a previous pregnancy presented at 8 weeks gestation with nausea, headache, and neck pain. Cerebrospinal fluid analysis was positive for recurrent coccidioidal infection. She was started on Amphotericin and discharged. She re-presented at 30 week's gestation with phonophobia and photophobia, emesis, neck pain and swelling. MRI showed evidence of ventriculomegaly with communicating hydrocephalus. She was treated with therapeutic lumbar punctures throughout her pregnancy and a ventriculoperitoneal shunt following delivery. She had a spontaneous vaginal delivery at 38 weeks and 3 days with no complications. CONCLUSION: This unique case highlights the susceptibility of recurrent disseminated coccidioidomycosis in subsequent pregnancies and treatment thereof.


Assuntos
Coccidioidomicose , Hidrocefalia , Meningite Fúngica , Humanos , Lactente , Feminino , Gravidez , Adulto , Coccidioidomicose/diagnóstico , Coccidioidomicose/tratamento farmacológico , Cervicalgia/complicações , Cervicalgia/tratamento farmacológico , Meningite Fúngica/diagnóstico , Meningite Fúngica/tratamento farmacológico , Meningite Fúngica/complicações , Anfotericina B/uso terapêutico , Hidrocefalia/etiologia
13.
ACS ES T Water ; 4(8): 3540-3549, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39144679

RESUMO

Wastewater-derived phosphate contributes to eutrophication if the phosphate is not efficiently removed before it is discharged to surface waters. In the Florida Keys (USA), shallow injection of treated wastewater into saline limestone aquifers is a common mode of wastewater disposal. We assessed the possibility of efficient and permanent phosphate removal following injection at a wastewater treatment facility in Marathon, Florida. The concentrations of nutrients, dissolved ions, and anthropogenic compounds in groundwater and nearshore waters were monitored over two years, as was the progression of a patch of fluorescent dye emplaced by the wastewater injection well. The density contrast between the wastewater effluent and saline groundwater caused the effluent plume to buoy to the shallow subsurface near the injection well. Soluble reactive phosphorus (SRP) and sucralose were both detected in nearshore waters, indicating incomplete removal of contaminants. However, ∼75% of the SRP is removed from the plume in the first 10 days of transit by adsorption followed by a slower removal mechanism, bringing the P removal efficiency above 90%. A positive relationship between excess calcium and phosphate removal efficiency, together with high levels of calcium phosphate mineral supersaturation, supports calcite dissolution followed by calcium phosphate mineralization as this slower removal process.

14.
Bioresour Technol ; 406: 130973, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38879051

RESUMO

In Brazil the main feedstock used for ethanol production is sugarcane juice, resulting in large amounts of bagasse. Bagasse has high potential for cellulosic ethanol production, and consolidated bioprocessing (CBP) has potential for lowering costs. However, economic feasibility requires bioprocessing at high solids loadings, entailing engineering and biological challenges. This study aims to document and characterize carbohydrate solubilization and utilization by defined cocultures of Clostridium thermocellum and Thermoanaerobacterium thermosaccharolyticum at increasing loadings of sugarcane bagasse. Results show that fractional carbohydrate solubilization decreases as solids loading increases from 10 g/L to 80 g/L. Cocultures enhance solubilization and carbohydrate utilization compared to monocultures, irrespective of initial solids loading. Rinsing bagasse before fermentation slightly decreases solubilization. Experiments studying inhibitory effects using spent media and dilution of broth show that negative effects are temporary or reversible. These findings highlight the potential of converting sugarcane bagasse via CBP, pointing out performance limitations that must be addressed.


Assuntos
Celulose , Clostridium thermocellum , Saccharum , Solubilidade , Thermoanaerobacterium , Saccharum/química , Celulose/química , Celulose/metabolismo , Thermoanaerobacterium/metabolismo , Clostridium thermocellum/metabolismo , Fermentação , Técnicas de Cocultura , Etanol/metabolismo
15.
Case Rep Ophthalmol Med ; 2024: 3878152, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38765219

RESUMO

Purpose. We describe a patient with normal tension glaucoma (NTG) of several years whose management was complicated by the presence of a giant internal carotid-ophthalmic artery aneurysm. Observations. A 72-year-old woman presented to our glaucoma clinic with accelerated deterioration of her vision in her left eye (OS) over a 1-month period. Her ophthalmic history was most notable for bilateral NTG diagnosed 3 years prior which had been treated with several laser trabeculoplasty OS and topical bimatoprost 0.01% eye drops in both eyes (OU). Upon evaluation, her visual acuity OS had worsened, and visual field (VF) testing showed extensive progressive losses temporally and pericentrally OS over a year with stable IOP measurements and no neurological complaints. Given her atypical NTG progression, she was referred for an urgent neurological evaluation which revealed an unruptured giant left internal carotid-ophthalmic aneurysm. Following the successful treatment of the aneurysm with platinum coils, she continued to demonstrate additional bilateral ophthalmic changes including further progression of VF loss and RNFL thinning OS > OD on follow-up. Conclusion and Importance. Overall, this report describes a unique complication in the management of a patient with chronic bilateral NTG in the form of a giant internal carotid-ophthalmic aneurysm. Moreover, it highlights the need for clinicians to maintain a degree of suspicion for compressive lesions of the optic nerve when presented with atypical progression of VFs and/or visual acuity loss in glaucomatous patients.

16.
JACC Case Rep ; 29(10): 102322, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38601846

RESUMO

Uhl anomaly is characterized by the morphologic absence of right ventricular myocardium and is an exceedingly rare cause of nonischemic cardiomyopathy. We report the first case of a successful heart transplantation in a 41-year-old patient who presented in cardiogenic shock from Uhl anomaly causing decompensated right ventricular failure.

17.
Biotechnol Biofuels Bioprod ; 17(1): 76, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38831375

RESUMO

BACKGROUND: The aim of this study was to increase the accessibility and accelerate the breakdown of lignocellulosic biomass to methane in an anaerobic fermentation system by mechanical cotreatment: milling during fermentation, as an alternative to conventional pretreatment prior to biological deconstruction. Effluent from a mesophilic anaerobic digester running with unpretreated senescent switchgrass as the predominant carbon source was collected and subjected to ball milling for 0.5, 2, 5 and 10 min. Following this, a batch fermentation test was conducted with this material in triplicate for an additional 18 days with unmilled effluent as the 'status quo' control. RESULTS: The results indicate 0.5 - 10 min of cotreatment increased sugar solubilization by 5- 13% when compared to the unmilled control, with greater solubilization correlated with increased milling duration. Biogas concentrations ranged from 44% to 55.5% methane with the balance carbon dioxide. The total biogas production was statistically higher than the unmilled control for all treatments with 2 or more minutes of milling (α = 0.1). Cotreatment also decreased mean particle size. Energy consumption measurements of a lab-scale mill indicate that longer durations of milling offer diminishing benefits with respect to additional methane production. CONCLUSIONS: Cotreatment in anaerobic digestion systems, as demonstrated in this study, provides an alternative approach to conventional pretreatments to increase biogas production from lignocellulosic grassy material.

18.
Psychol Trauma ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38976387

RESUMO

OBJECTIVE: Bisexual women experience higher rates of sexual assault (SA) and posttrauma distress compared to monosexual women. We examined the patterns of reactions to SA disclosure (positive and two types of negative) and bisexual minority stress (antibisexual stigma from heterosexual and lesbian/gay people, internalized binegativity) experienced by young bisexual women who experienced adult SA. We also examined differences in assault-related experiences, posttraumatic stress disorder and depression symptoms, and hazardous drinking based on the identified patterns. METHOD: The current sample was drawn from two parent samples of women and included survivors who had disclosed an adult SA: (a) n = 149 bisexual women (98% cisgender, ages 18-35, 87.9% White) recruited via Amazon's Mechanical Turk and (b) n = 81 cisgender bisexual women (ages 18-25, 84% White) recruited via online ads. Latent profile analyses and analyses of variance were conducted. RESULTS: Analyses identified four latent profiles characterized by: (a) low stigmatizing responses, (b) high negative SA disclosure reactions, (c) high antibisexual stigma, and (d) highest stigmatizing responses. The fourth profile had higher posttraumatic stress disorder and depression symptoms and hazardous drinking compared to the other profiles. CONCLUSIONS: Results suggest women in the profile characterized by highest negative reactions to SA disclosure and highest bisexual minority stress (antibisexual stigma and internalized binegativity) may experience greatest distress postassault. Results highlight the importance for researchers, policymakers, and clinicians to consider and address both SA-related and identity-related stigma among bisexual survivors. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

19.
Microbiome ; 12(1): 88, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38741135

RESUMO

BACKGROUND: During the bloom season, the colonial cyanobacterium Microcystis forms complex aggregates which include a diverse microbiome within an exopolymer matrix. Early research postulated a simple mutualism existing with bacteria benefitting from the rich source of fixed carbon and Microcystis receiving recycled nutrients. Researchers have since hypothesized that Microcystis aggregates represent a community of synergistic and interacting species, an interactome, each with unique metabolic capabilities that are critical to the growth, maintenance, and demise of Microcystis blooms. Research has also shown that aggregate-associated bacteria are taxonomically different from free-living bacteria in the surrounding water. Moreover, research has identified little overlap in functional potential between Microcystis and members of its microbiome, further supporting the interactome concept. However, we still lack verification of general interaction and know little about the taxa and metabolic pathways supporting nutrient and metabolite cycling within Microcystis aggregates. RESULTS: During a 7-month study of bacterial communities comparing free-living and aggregate-associated bacteria in Lake Taihu, China, we found that aerobic anoxygenic phototrophic (AAP) bacteria were significantly more abundant within Microcystis aggregates than in free-living samples, suggesting a possible functional role for AAP bacteria in overall aggregate community function. We then analyzed gene composition in 102 high-quality metagenome-assembled genomes (MAGs) of bloom-microbiome bacteria from 10 lakes spanning four continents, compared with 12 complete Microcystis genomes which revealed that microbiome bacteria and Microcystis possessed complementary biochemical pathways that could serve in C, N, S, and P cycling. Mapping published transcripts from Microcystis blooms onto a comprehensive AAP and non-AAP bacteria MAG database (226 MAGs) indicated that observed high levels of expression of genes involved in nutrient cycling pathways were in AAP bacteria. CONCLUSIONS: Our results provide strong corroboration of the hypothesized Microcystis interactome and the first evidence that AAP bacteria may play an important role in nutrient cycling within Microcystis aggregate microbiomes. Video Abstract.


Assuntos
Lagos , Microbiota , Microcystis , Microcystis/genética , Microcystis/metabolismo , Microcystis/crescimento & desenvolvimento , China , Lagos/microbiologia , Nutrientes/metabolismo , Processos Fototróficos , Aerobiose , Eutrofização , Bactérias/classificação , Bactérias/metabolismo , Bactérias/genética , Bactérias/isolamento & purificação , Nitrogênio/metabolismo , Carbono/metabolismo
20.
Bioresour Technol ; 406: 130982, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38879055

RESUMO

Cotreatment, mechanical disruption of lignocellulosic biomass during microbial fermentation, is a potential alternative to thermochemical pretreatment as a means of increasing the accessibility of lignocellulose to biological attack. Successful implementation of cotreatment requires microbes that can withstand milling, while solubilizing and utilizing carbohydrates from lignocellulose. In this context, cotreatment with thermophilic, lignocellulose-fermenting bacteria has been successfully evaluated for a number of lignocellulosic feedstocks. Here, cotreatment was applied to sugarcane bagasse using monocultures of the cellulose-fermenting Clostridium thermocellum and cocultures with the hemicellulose-fermenting Thermoanaerobacterium thermosaccharolyticum. This resulted in 76 % carbohydrate solubilization (a 1.8-fold increase over non-cotreated controls) on 10 g/L solids loading, having greater effect on the hemicellulose fraction. With cotreatment, fermentation by wild-type cultures at low substrate concentrations increased cumulative product formation by 45 % for the monoculture and 32 % for the coculture. These findings highlight the potential of cotreatment for enhancing deconstruction of sugarcane bagasse using thermophilic bacteria.


Assuntos
Celulose , Técnicas de Cocultura , Fermentação , Saccharum , Solubilidade , Saccharum/química , Celulose/metabolismo , Celulose/química , Clostridium thermocellum/metabolismo , Thermoanaerobacterium/metabolismo , Lignina/metabolismo , Lignina/química , Bactérias Anaeróbias/metabolismo
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