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1.
bioRxiv ; 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38712281

RESUMO

Non-alcoholic fatty liver disease (NAFLD) - characterized by excess accumulation of fat in the liver - now affects one third of the world's population. As NAFLD progresses, extracellular matrix components including collagen accumulate in the liver causing tissue fibrosis, a major determinant of disease severity and mortality. To identify transcriptional regulators of fibrosis, we computationally inferred the activity of transcription factors (TFs) relevant to fibrosis by profiling the matched transcriptomes and epigenomes of 108 human liver biopsies from a deeply-characterized cohort of patients spanning the full histopathologic spectrum of NAFLD. CRISPR-based genetic knockout of the top 100 TFs identified ZNF469 as a regulator of collagen expression in primary human hepatic stellate cells (HSCs). Gain- and loss-of-function studies established that ZNF469 regulates collagen genes and genes involved in matrix homeostasis through direct binding to gene bodies and regulatory elements. By integrating multiomic large-scale profiling of human biopsies with extensive experimental validation we demonstrate that ZNF469 is a transcriptional regulator of collagen in HSCs. Overall, these data nominate ZNF469 as a previously unrecognized determinant of NAFLD-associated liver fibrosis.

2.
Dermatol Surg ; 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38700380

RESUMO

BACKGROUND: Risk stratification can identify individuals in primary care settings who are at increased risk of developing melanoma. OBJECTIVE: Converting and implementing a validated risk stratification tool as a patient self-administered tablet-based survey. METHODS: Mackie risk stratification tool was transformed into a patient questionnaire. The questionnaire was completed in academic dermatologist practices by patients and dermatologists and revised to optimize sensitivity and specificity using physician assessment as gold standard. The optimized survey was administered before routine primary care visits during 2019 to 2021. High-risk patients were referred to dermatology. The number needed to screen (NNS), sensitivity, specificity, positive predictive value, and negative predictive value to identify a melanoma were calculated. RESULTS: Of the 7,893 respondents, 5,842 (74%) and 2,051 (26%) patients were categorized as low-risk and high-risk population, respectively. The NNS to identify 1 melanoma was 64 in the high-risk population. CONCLUSION: Incorporating self-administered patient-risk stratification tools in primary care settings can identify high-risk individuals for targeted melanoma screening. Further studies are needed to optimize specificity and sensitivity in more targeted populations.

3.
Int Wound J ; 21(4): e14882, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38606794

RESUMO

As the incidence of diabetic foot ulcers (DFU) increases, better treatments that improve healing should reduce complications of these ulcers including infections and amputations. We conducted a randomized controlled trial comparing outcomes between a novel purified reconstituted bilayer membrane (PRBM) to the standard of care (SOC) in the treatment of non-healing DFUs. This study included 105 patients who were randomized to either of two treatment groups (n = 54 PRBM; n = 51 SOC) in the intent to treat (ITT) group and 80 who completed the study per protocol (PP) (n = 47 PRBM; n = 33 SOC). The primary endpoint was the percentage of wounds closed after 12 weeks. Secondary outcomes included percent area reduction, time to healing, quality of life, and cost to closure. The DFUs that had been treated with PRBM healed at a higher rate than those treated with SOC (ITT: 83% vs. 45%, p = 0.00004, PP: 92% vs. 67%, p = 0.005). Wounds treated with PRBM also healed significantly faster than those treated with SOC with a mean of 42 versus 62 days for SOC (p = 0.00074) and achieved a mean wound area reduction within 12 weeks of 94% versus 51% for SOC (p = 0.0023). There were no adverse events or serious adverse events that were related to either the PRBM or the SOC. In comparison to the SOC, DFUs healed faster when treated with PRBM. Thus, the use of this PRBM is an effective option for the treatment of chronic DFUs.


Assuntos
Diabetes Mellitus , Pé Diabético , Humanos , Pé Diabético/cirurgia , Padrão de Cuidado , Estudos Prospectivos , Qualidade de Vida , Cicatrização , Resultado do Tratamento
4.
EJHaem ; 5(2): 408-409, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38633113
5.
J Subst Use Addict Treat ; 162: 209376, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38641053

RESUMO

BACKGROUND: Due to the considerably heightened risk of overdose immediately following jail or prison release, expansion of harm reduction interventions for citizens returning to the community after an incarceration episode should be of utmost concern. However, there are no studies examining the adoption and use of harm reduction among this population. This short report examines the use of individual-level harm reduction strategies (HRS) among people who use drugs, comparing those who have lifetime histories of incarceration with those who do not. METHODS: This study included baseline data (N = 274) from a larger clinical trial, which recruited participants at two syringe service programs. Fisher's exact tests examine correlations between HRS and lifetime incarceration. RESULTS: Significant variation in HRS use were observed by demographic characteristics. Those with lifetime incarceration histories were less likely to report ensuring naloxone was available when using, using when others were present, using fentanyl test strips, using a trusted drug supplier, and using some other HRS compared to those without lifetime incarceration histories. Similarly, those with lifetime incarceration histories were also less likely to report using non-prescribed buprenorphine and methadone, which could potentially reduce overdose risk even if not explicitly used as an HRS. CONCLUSION: The results suggest that one of the populations at highest risk of overdose is least likely to use strategies that may reduce overdose risk. Targeted efforts to increase exposure to HRS learning opportunities and access to these resources could help reduce overdose disparities for people returning to the community after incarceration.

6.
Compend Contin Educ Dent ; 45(4): 204-208, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38622080

RESUMO

Oral piercing habits are associated with various degrees of complications. Tongue piercing increases the risk of gingival recession and infrabony defects, subsequently leading to localized periodontitis. In the case presented, the patient had persistent swelling and suppuration around her mandibular anterior teeth attributed to tongue piercing jewelry that was placed approximately 12 years prior. Intraoral examinations revealed a localized deep pocket, purulent discharge, swelling, plaque accumulation, bleeding on probing, gingival recession, and teeth mobility. The patient was diagnosed with localized stage III, grade C periodontitis. Following full-mouth debridement and the placement of an extracoronal lingual splint, minimally invasive, papillae-sparing incisions were made, and regenerative therapy with bone allograft and collagen membrane was used to manage the infrabony defects. During the 18-month postoperative follow-up, complete soft-tissue healing was observed along with a significant reduction in pocket depth and the absence of bleeding on probing or suppuration. Radiographic evaluation showed evidence of bone fill. The reported case demonstrates how careful diagnosis and treatment planning are crucial for managing different periodontal defects and emphasizes the importance of proficient periodontal management, which can save teeth that would otherwise be extracted and replaced with implant therapy or fixed bridgework.


Assuntos
Perda do Osso Alveolar , Piercing Corporal , Placa Dentária , Retração Gengival , Periodontite , Humanos , Feminino , Piercing Corporal/efeitos adversos , Periodontite/complicações , Retração Gengival/etiologia , Retração Gengival/cirurgia , Placa Dentária/complicações , Regeneração Tecidual Guiada Periodontal , Supuração/complicações , Supuração/cirurgia , Perda da Inserção Periodontal/etiologia , Perda da Inserção Periodontal/cirurgia , Perda do Osso Alveolar/cirurgia , Seguimentos
7.
Proc Natl Acad Sci U S A ; 121(20): e2320600121, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38684006

RESUMO

The increasing prevalence of low snow conditions in a warming climate has attracted substantial attention in recent years, but a focus exclusively on low snow leaves high snow years relatively underexplored. However, these large snow years are hydrologically and economically important in regions where snow is critical for water resources. Here, we introduce the term "snow deluge" and use anomalously high snowpack in California's Sierra Nevada during the 2023 water year as a case study. Snow monitoring sites across the state had a median 41 y return interval for April 1 snow water equivalent (SWE). Similarly, a process-based snow model showed a 54 y return interval for statewide April 1 SWE (90% CI: 38 to 109 y). While snow droughts can result from either warm or dry conditions, snow deluges require both cool and wet conditions. Relative to the last century, cool-season temperature and precipitation during California's 2023 snow deluge were both moderately anomalous, while temperature was highly anomalous relative to recent climatology. Downscaled climate models in the Shared Socioeconomic Pathway-370 scenario indicate that California snow deluges-which we define as the 20 y April 1 SWE event-are projected to decline with climate change (58% decline by late century), although less so than median snow years (73% decline by late century). This pattern occurs across the western United States. Changes to snow deluge, and discrepancies between snow deluge and median snow year changes, could impact water resources and ecosystems. Understanding these changes is therefore critical to appropriate climate adaptation.

8.
J Craniofac Surg ; 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38563558

RESUMO

OBJECTIVES: Dermal regeneration templates (DRTs) are frequently used to treat scalp defects. The aim was to compare the time course of healing for DRTs in scalp defects with and without preoperative radiation. METHODS: The authors conducted a retrospective cohort study of DRT-based scalp reconstruction at 2 academic medical centers between 2013 and 2022. Information was collected on demographic variables, comorbidities, medication use, history of radiation, and DRT outcomes. The primary outcome was DRT loss, defined as exposed calvarium or DRT detachment based on postoperative follow-up documentation. Kaplan-Meier survival analysis and multivariable Cox proportional-hazard regressions were used to compare DRT loss in irradiated and nonirradiated defects. Multivariable logistic regressions were used to compare 30-day postoperative complications (infection, hematoma, or seroma) in irradiated and nonirradiated defects. RESULTS: In total, 158 cases were included. Twenty-eight (18%) patients had a preoperative history of radiation to the scalp. The mean follow-up time after DRT placement was 2.6 months (SD: 4.5 mo). The estimated probability of DRT survival at 2 months was 91% (95% CI: 83%-100%) in nonirradiated patients and 65% (95% CI: 48%-88%) in irradiated patients. In the 55 patients with a bony wound base, preoperative head radiation was associated with a higher likelihood of DRT loss (hazard ratio: 11). Half the irradiated defects experienced uncomplicated total wound closure using Integra Wound Matrix Dressing with or without second-stage reconstruction. CONCLUSIONS: Dermal regeneration template can offer durable coverage in nonirradiated scalp defects. Although DRT loss is more likely in irradiated scalp defects, successful DRT-based reconstruction is possible in select cases.

9.
Plast Reconstr Surg Glob Open ; 12(3): e5674, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38510326

RESUMO

Background: Dermal scaffolds have created a paradigm shift for burn and wound management by providing improved healing and less scarring, while improving cosmesis and functionality. Dermal regeneration template (DRT) is a bilayer membrane for dermal regeneration developed by Yannas and Burke in the 1980s. The aim of this review is to summarize clinical evidence for dermal scaffolds focusing on DRT for the management and reconstruction of burn injuries and complex wounds. Methods: A comprehensive search of PubMed was performed from the start of indexing through November 2022. Articles reporting on DRT use in patients with burns, limb salvage, and wound reconstruction were included with focus on high-level clinical evidence. Results: DRT has become an established alternative option for the treatment of full-thickness and deep partial-thickness burns, with improved outcomes in areas where cosmesis and functionality are important. In the management of diabetic foot ulcers, use of DRT is associated with high rates of complete wound healing with a low risk of adverse outcomes. DRT has been successfully used in traumatic and surgical wounds, showing particular benefit in deep wounds and in the reconstruction of numerous anatomical sites. Conclusions: Considerable clinical experience has accrued with the use of DRT beyond its original application for thermal injury. A growing body of evidence from clinical studies reports the successful use of DRT to improve clinical outcomes and quality of life across clinical indications at a number of anatomical sites.

10.
J Prosthodont ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38512996

RESUMO

PURPOSE: Complications can and do occur with implants and their restorations with causes having been proposed for some single implant complications but not for others. METHODS: A review of pertinent literature was conducted. A PubMed search of vibration, movement, and dentistry had 175 citations, while stress waves, movement, and dentistry had zero citations as did stress waves, movement. This paper discusses the physics of vibration, elastic and inelastic collision, and stress waves as potentially causative factors related to clinical complications. RESULTS: Multiple potential causes for interproximal contact loss have been presented, but it has not been fully understood. Likewise, theories have been suggested regarding the intrusion of natural teeth when they are connected to an implant as part of a fixed partial denture as well as intrusion when a tooth is located between adjacent implants, but the process of intrusion, and resultant extrusion, is not fully understood. A third complication with single implants and their crowns is abutment screw loosening with several of the clinical characteristics having been discussed but without determining the underlying process(es). CONCLUSIONS: Interproximal contact loss, natural tooth intrusion, and abutment screw loosening are common complications that occur with implant retained restorations. Occlusion is a significant confounding variable. The hypothesis is that vibration, or possibly stress waves, generated from occlusal impact forces on implant crowns and transmitted to adjacent teeth, are the causative factors in these events. Since occlusion appears to play a role in these complications, it is recommended that occlusal contacts provide centralized stability on implant crowns and not be located on any inclined surfaces that transmit lateral forces that could be transmitted to an adjacent tooth and cause interproximal contact loss or intrusion. The intensity, form, and location of proximal contacts between a natural tooth located between adjacent single implant crowns seem to play a role in the intrusion of the natural tooth. Currently, there is a lack of information about the underlying mechanisms related to these occurrences and research is needed to define any confounding variables.

11.
Crit Care ; 28(1): 95, 2024 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-38519972

RESUMO

BACKGROUND: Despite the growing prevalence of burn survivors, a gap persists in our understanding of the correlation between acute burn trauma and the long-term impact on psychosocial health. This study set out to investigate the prevalence of long-term pain and symptoms of anxiety and depression in survivors of extensive burns, comparing this to the general population, and identify injury and demographic-related factors predisposing individuals to psychosocial compromise. METHODS: RE-ENERGIZE was an international, double-blinded, randomized-controlled trial that enrolled 1200 patients with partial- or full-thickness burns that required surgical treatment. For the post hoc analysis, we excluded participants who did not complete the Short Form Health Survey (SF-36) questionnaire. Normative data were taken from the 2021 National Health Interview Survey dataset. Propensity score matching was performed using the nearest-neighbor 1-to-1 method, and the two cohorts were compared in terms of chronic pain, and symptoms of anxiety and depression. A multivariable analysis was performed on the burns cohort to identify factors predicting post-discharge pain and symptoms of anxiety and depression. RESULTS: A total of 600 burn patients and 26,666 general population adults were included in this study. Following propensity score matching, both groups comprised 478 participants each, who were predominately male, white, overweight and between 20 and 60 years old. Compared to the general population, burn patients were significantly more likely to report the presence of moderate and a lot of pain (p = 0.002). Symptoms of anxiety were significantly higher in the burn population in two of four levels (most of the time; some of the time; p < 0.0001 for both). Responders in the burn population were significantly less likely to report the absence of depressive symptoms (p < 0.0001). Burn patients were also significantly more likely to report that their mental health affects their social life. TBSA, history of depression, and female sex were identified as independently associated factors for pain, anxiety, and depressive symptoms. The presence of chronic pain and anxiety symptoms independently predicted for symptoms of depression. CONCLUSIONS: Analyzing the largest multicenter cohort of patients with extensive burns, we find that burn injury is associated with chronic pain, and symptoms of anxiety and depression. In addition, TBSA-burned and history of depression directly correlate with the prevalence of chronic pain, and symptoms of anxiety and depression. Finally, pain, and symptoms of anxiety and depression are interrelated and may have interactive effects on the process of recovery following burn injury. Burn patients would, therefore, benefit from a multidisciplinary team approach with early mobilization of pain and mental health experts, in order to promptly prevent the development of psychosocial challenges and their consequences.


Assuntos
Dor Crônica , Depressão , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Assistência ao Convalescente , Ansiedade/epidemiologia , Ansiedade/etiologia , Ansiedade/psicologia , Dor Crônica/epidemiologia , Dor Crônica/etiologia , Depressão/epidemiologia , Depressão/etiologia , Depressão/psicologia , Alta do Paciente , Qualidade de Vida , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto
12.
Microsurgery ; 44(4): e31156, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38549404

RESUMO

INTRODUCTION: Significant morbidity and mortality are hallmarks of the functional decline seen in physically frail patients. The modified frailty index 5 (mFI-5) represents a risk predictor score that has been validated as a comorbidity-based scale in surgery. Serum albumin levels of <3.5 g/dL (hypoalbuminemia) have also been implicated with poor postoperative outcomes. However, the association between these two parameters remains to be investigated. We aimed to elucidate the interdependence of preoperative albumin levels and frailty, as evaluated by the mFI-5 score, and its reliability to prognosticate postoperative results in free flap reconstruction (FFR). METHODS: We conducted a multicenter, retrospective cohort study and accessed the ACS National Surgical Quality Improvement Program (ACS-NSQIP) from 2008 to 2021. We identified all adult patients (≥18 years of age) who underwent a FFR. We extracted perioperative data and lab values including albumin. Multivariable linear and logistic regression analyses were performed to identify independent risk predictors. Main outcomes involved mortality, length of hospital stay, reoperation, medical and surgical complications, and discharge destination within the 30-day postoperative period. RESULTS: A total of 34,571 patients were included in the study, with an average age of 53.9 years (standard deviation [SD] 12.2) and an average body mass index (BMI) of 28.8 (SD 6.1). Of these patients, 7484 were male (21.6%), whereas 22,363 (64.7%) had no frailty (mFI = 0). Additionally, 9466 patients had a frailty score of 1 (27.4%), 2505 had a score of 2 (7.2%), 226 had a score of 3 (0.7%), and 11 had a score of 4 or higher (0.0%). Albumin levels were available for 16,250 patients (47.0%), and among them, 1334 (8.2%) had hypoalbuminemia. Regression analyses showed that higher mFI scores were independent predictors of any, surgical, and medical complications, as well as increased rates of reoperations, unplanned readmissions, and prolonged hospital stays. Hypoalbuminemia independently predicted any, surgical, and medical complications, and higher mortality, reoperation, and longer hospital stay. When both frailty and albumin levels (mFI-5 and albumin) were considered together, this combined assessment was found to be a more accurate predictor of all major outcomes (any, medical and surgical complications, mortality, and reoperation). Further, our analysis identified a weak negative correlation between serum albumin levels and mFI scores (Spearman R: -.1; p < .0001). CONCLUSION: In conclusion, this cohort study highlights the association of hypoalbuminemia with adverse postoperative outcomes, including those not directly related to frailty. Simultaneously, higher mFI scores independently predicted outcomes not associated with hypoalbuminemia. Stemming from these findings, we recommend considering both serum albumin levels and frailty in patients receiving FFR. This perioperative algorithm may help provide more individualized planning including multidisciplinary care and pre and posthabilitation.


Assuntos
Fragilidade , Retalhos de Tecido Biológico , Hipoalbuminemia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fragilidade/complicações , Hipoalbuminemia/complicações , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Reprodutibilidade dos Testes , Estudos Retrospectivos , Medição de Risco/métodos , Fatores de Risco , Albumina Sérica
14.
Zootaxa ; 5424(3): 323-357, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38480282

RESUMO

All eight extant species ofRhabdopleuradescribed between 1869 and 2018 are provisionally accepted as valid based on a review of the literature and new data on two little-known species from the Azores. Additionally, four new species are described from the New Zealand region, increasing global diversity by 50%, and a dichotomous key to all 12 described species is provided based on morphological criteria. The distinction between colony morphologies based on erect-tube inception is regarded as particularly helpful in initial characterization of species. Erect ringed tubes are either produced directly from the surface of creeping-tubes or indirectly, i.e. a short adherent side branch from a creeping tube is interpolated between the creeping tube and an erect tube; such side branches are blind-ending. These two modes of erect-tube origination are here respectively termeddirectandindirect. Species with indirect erect-tube budding are predominant in the North Atlantic whereas species with direct erect-tube budding dominate in New Zealand waters. The only indirect-erect species from New Zealand, Rhabdopleura chathamica n. sp., was discovered on deepwater coral from 10081075 m, constituting the deepest record of the genus to date. Rhabdopleura emancipata n. sp., collected only in a detached state, constitutes a three-dimensional tangled growth that grew freely into the water columna unique morphology hitherto unknown among extant species. Owing to this growth mode, it provided a substratum for epibionts from several phyla. Rhabdopleura francesca n. sp. and Rhabdopleura decipula n. sp. are morphologically very similar but are distinguishable by their distinct placements in a phylogeny based on 16S mitochondrial and 18S nuclear rRNA genes. Phylogenetic reconstructions based on rRNA and mitochondrial genome data contribute to an updated phylogeny of all Rhabdopleura species sequenced thus far, some of which require more molecular sequences and morphological analyses for taxonomic determination.


Assuntos
Mitocôndrias , Animais , Filogenia , Nova Zelândia , RNA Ribossômico 18S/genética , Sequência de Bases , Mitocôndrias/genética
15.
Front Bioeng Biotechnol ; 12: 1363803, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38481571

RESUMO

Introduction: Daunorubicin and doxorubicin, two anthracycline polyketides produced by S. peucetius, are potent anticancer agents that are widely used in chemotherapy, despite severe side effects. Recent advances have highlighted the potential of producing improved derivatives with reduced side effects by incorporating l-rhodosamine, the N,N-dimethyl analogue of the native amino sugar moiety. Method: In this study, we aimed to produce N,N-dimethylated anthracyclines by engineering the doxorubicin biosynthetic pathway in the industrial Streptomyces peucetius strain G001. To achieve this, we introduced genes from the aclarubicin biosynthetic pathway encoding the sugar N-methyltransferases AclP and AknX2. Furthermore, the native gene for glycosyltransferase DnrS was replaced with genes encoding the aclarubicin glycosyltransferases AknS and AknT. Additionally, the gene for methylesterase RdmC from the rhodomycin biosynthetic pathway was introduced. Results: A new host was engineered successfully, whereby genes from the aclarubicin pathway were introduced and expressed. LC-MS/MS analysis of the engineered strains showed that dimethylated sugars were efficiently produced, and that these were incorporated ino the anthracycline biosynthetic pathway to produce the novel dimethylated anthracycline N,N-dimethyldaunorubicin. Further downstream tailoring steps catalysed by the cytochrome P450 monooxygenase DoxA exhibited limited efficacy with N,N-dimethylated substrates. This resulted in only low production levels of N,N-dimethyldaunorubicin and no N,N-dimethyldoxorubicin, most likely due to the low affinity of DoxA for dimethylated substrates. Discussion: S. peucetius G001 was engineered such as to produce N,N-dimethylated sugars, which were incorporated into the biosynthetic pathway. This allowed the successful production of N,N-dimethyldaunorubicin, an anticancer drug with reduced cytotoxicity. DoxA is the key enzyme that determines the efficiency of the biosynthesis of N,N-dimethylated anthracyclines, and engineering of this enzyme will be a major step forwards towards the efficient production of more N,N-dimethylated anthracyclines, including N,N-dimethyldoxorubicin. This study provides valuable insights into the biosynthesis of clinically relevant daunorubicin derivatives, highlighting the importance of combinatorial biosynthesis.

16.
bioRxiv ; 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38464227

RESUMO

Selective and controlled expansion of endogenous ß-cells has been pursued as a potential therapy for diabetes. Ideally, such therapies would preserve feedback control of ß-cell proliferation to avoid excessive ß-cell expansion and an increased risk of hypoglycemia. Here, we identified a regulator of ß-cell proliferation whose inactivation results in controlled ß-cell expansion: the protein deacetylase Sirtuin 2 (SIRT2). Sirt2 deletion in ß-cells of mice increased ß-cell proliferation during hyperglycemia with little effect in homeostatic conditions, indicating preservation of feedback control of ß-cell mass. SIRT2 restrains proliferation of human islet ß-cells cultured in glucose concentrations above the glycemic set point, demonstrating conserved SIRT2 function. Analysis of acetylated proteins in islets treated with a SIRT2 inhibitor revealed that SIRT2 deacetylates enzymes involved in oxidative phosphorylation, dampening the adaptive increase in oxygen consumption during hyperglycemia. At the transcriptomic level, Sirt2 inactivation has context-dependent effects on ß-cells, with Sirt2 controlling how ß-cells interpret hyperglycemia as a stress. Finally, we provide proof-of-principle that systemic administration of a GLP1-coupled Sirt2-targeting antisense oligonucleotide achieves ß-cell selective Sirt2 inactivation and stimulates ß-cell proliferation under hyperglycemic conditions. Overall, these studies identify a therapeutic strategy for increasing ß-cell mass in diabetes without circumventing feedback control of ß-cell proliferation.

17.
Genetics ; 227(1)2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38531678

RESUMO

Genetic screens for recessive alleles induce mutations, make the mutated chromosomes homozygous, and then assay those homozygotes for the phenotype of interest. When screening for genes required for female meiosis, the phenotype of interest has typically been nondisjunction from chromosome segregation errors. As this requires that mutant females be viable and fertile, any mutants that are lethal or sterile when homozygous cannot be recovered by this approach. To overcome these limitations, we have screened the VALIUM22 collection of RNAi constructs that target germline-expressing genes in a vector optimized for germline expression by driving RNAi with GAL4 under control of a germline-specific promoter (nanos or mat-alpha4). This allowed us to test genes that would be lethal if knocked down in all cells, and by examining unfertilized metaphase-arrested mature oocytes, we could identify defects in sterile females. After screening >1,450 lines of the collection for two different defects (chromosome congression and the hypoxic sequestration of Mps1-GFP to ooplasmic filaments), we obtained multiple hits for both phenotypes, identified novel meiotic phenotypes for genes that had been previously characterized in other processes, and identified the first phenotypes to be associated with several previously uncharacterized genes.


Assuntos
Drosophila melanogaster , Meiose , Interferência de RNA , Animais , Feminino , Meiose/genética , Drosophila melanogaster/genética , Fenótipo , Oócitos/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Testes Genéticos/métodos , Masculino
18.
Zoological Lett ; 10(1): 4, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38321566

RESUMO

Pachyzoidae is a little-known family of deep-sea ctenostome Bryozoa that until now was monospecific for Pachyzoon atlanticum. Originally described from the Atlantic Ocean, the genus was also found off southeastern New Caledonia in deep waters of the geological continent of Zealandia. Pachyzoon atlanticum forms globular to flat round colonies, living on soft, muddy to sandy bottoms with a few rhizoidal cystid appendages extending from the basal, substrate-oriented side. In this study, we investigate additional pachyzoids, collected between 1965 and 2015 from over 40 sites around New Zealand, by means of detailed morphological and histological investigations. In total, several hundred colonies were encountered in the NIWA Invertebrate Collection, comprising two new species of the genus Pachyzoon, P. grischenkoi sp. nov. and P. pulvinaris sp. nov., and the new genus and species Jeanloupia zealandica gen. et sp. nov.. The genus Jeanloupia is characterized by small disc-shaped colonies with highly elongated peristomes and a quadrangular aperture, distinct from the round apertures of the genus Pachyzoon. Pachyzoid species differ in colony structure and shape, apertural papillae and polypide features such as tentacle number or digestive-tract details. Cystid appendages are non-kenozooidal, but may originate from laterally flanking kenozooids. Based on published images, alleged P. atlanticum from New Caledonia is re-interpreted as P. pulvinaris n. sp.. Morphological characters support alcyonidioidean relationships, as previously suggested. First observations on pachyzoid reproduction show macrolecithal oocytes and brooding of embryos, which seems to be the general pattern for this family. The occurrence of three new Zealandian species in a comparatively small geographical area far from the Atlantic indicates a high possibility of more species to discovered.

19.
Geohealth ; 8(2): e2024GH001022, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38371354

RESUMO

In 2023 human populations experienced multiple record-breaking climate events, with widespread impacts on human health and well-being. These events include extreme heat domes, drought, severe storms, flooding, and wildfires. Due to inherent lags in the climate system, we can expect such extremes to continue for multiple decades after reaching net zero carbon emissions. Unfortunately, despite these significant current and future impacts, funding for research in climate and health has lagged behind that for other geoscience and biomedical research. While some initial efforts from funding agencies are evident, there is still a significant need to increase the resources available for multidisciplinary research in the face of this issue. As a group of experts at this important intersection, we call for a more concerted effort to encourage interdisciplinary and policy-relevant investigations into the detrimental health effects of continued climate change.

20.
JMIR Res Protoc ; 13: e52205, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38329783

RESUMO

BACKGROUND: A considerable number of minors in the United States are diagnosed with developmental or psychiatric conditions, potentially influenced by underdiagnosis factors such as cost, distance, and clinician availability. Despite the potential of digital phenotyping tools with machine learning (ML) approaches to expedite diagnoses and enhance diagnostic services for pediatric psychiatric conditions, existing methods face limitations because they use a limited set of social features for prediction tasks and focus on a single binary prediction, resulting in uncertain accuracies. OBJECTIVE: This study aims to propose the development of a gamified web system for data collection, followed by a fusion of novel crowdsourcing algorithms with ML behavioral feature extraction approaches to simultaneously predict diagnoses of autism spectrum disorder and attention-deficit/hyperactivity disorder in a precise and specific manner. METHODS: The proposed pipeline will consist of (1) gamified web applications to curate videos of social interactions adaptively based on the needs of the diagnostic system, (2) behavioral feature extraction techniques consisting of automated ML methods and novel crowdsourcing algorithms, and (3) the development of ML models that classify several conditions simultaneously and that adaptively request additional information based on uncertainties about the data. RESULTS: A preliminary version of the web interface has been implemented, and a prior feature selection method has highlighted a core set of behavioral features that can be targeted through the proposed gamified approach. CONCLUSIONS: The prospect for high reward stems from the possibility of creating the first artificial intelligence-powered tool that can identify complex social behaviors well enough to distinguish conditions with nuanced differentiators such as autism spectrum disorder and attention-deficit/hyperactivity disorder. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/52205.

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