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1.
PLoS Genet ; 20(8): e1011362, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39110773

ABSTRACT

A recently reported Schizophrenia-associated genetic variant in the 3'UTR of the human furin gene, a homolog of C. elegans kpc-1, highlights an important role of the furin 3'UTR in neuronal development. We isolate three kpc-1 mutants that display abnormal dendrite arborization in PVD neurons and defective male mating behaviors. We show that the kpc-1 3'UTR participates in dendrite branching and self-avoidance. The kpc-1 3'UTR facilitates mRNA localization to branching points and contact points between sibling dendrites and promotes translation efficiency. A predicted secondary structural motif in the kpc-1 3'UTR is required for dendrite self-avoidance. Animals with over-expression of DMA-1, a PVD dendrite receptor, exhibit similar dendrite branching and self-avoidance defects that are suppressed with kpc-1 over-expression. Our results support a model in which KPC-1 proteins are synthesized at branching points and contact points to locally down-regulate DMA-1 receptors to promote dendrite branching and self-avoidance of a mechanosensory neuron important for male courtship.


Subject(s)
3' Untranslated Regions , Caenorhabditis elegans Proteins , Caenorhabditis elegans , Courtship , Dendrites , RNA, Messenger , Animals , Caenorhabditis elegans Proteins/genetics , Caenorhabditis elegans Proteins/metabolism , Male , Dendrites/metabolism , Dendrites/genetics , Caenorhabditis elegans/genetics , Caenorhabditis elegans/metabolism , 3' Untranslated Regions/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism , Protein Biosynthesis , Sexual Behavior, Animal/physiology , Humans , Mutation , Membrane Proteins
2.
Proc Natl Acad Sci U S A ; 119(45): e2210053119, 2022 Nov 08.
Article in English | MEDLINE | ID: mdl-36322763

ABSTRACT

Choreographic dendritic arborization takes place within a defined time frame, but the timing mechanism is currently not known. Here, we report that the precisely timed lin-4-lin-14 regulatory circuit triggers an initial dendritic growth activity, whereas the precisely timed lin-28-let-7-lin-41 regulatory circuit signals a subsequent developmental decline in dendritic growth ability, hence restricting dendritic arborization within a set time frame. Loss-of-function mutations in the lin-4 microRNA gene cause limited dendritic outgrowth, whereas loss-of-function mutations in its direct target, the lin-14 transcription factor gene, cause precocious and excessive outgrowth. In contrast, loss-of-function mutations in the let-7 microRNA gene prevent a developmental decline in dendritic growth ability, whereas loss-of-function mutations in its direct target, the lin-41 tripartite motif protein gene, cause further decline. lin-4 and let-7 regulatory circuits are expressed in the right place at the right time to set start and end times for dendritic arborization. Replacing the lin-4 upstream cis-regulatory sequence at the lin-4 locus with a late-onset let-7 upstream cis-regulatory sequence delays dendrite arborization, whereas replacing the let-7 upstream cis-regulatory sequence at the let-7 locus with an early-onset lin-4 upstream cis-regulatory sequence causes a precocious decline in dendritic growth ability. Our results indicate that the lin-4-lin-14 and the lin-28-let-7-lin-41 regulatory circuits control the timing of dendrite arborization through antagonistic regulation of the DMA-1 receptor level on dendrites. The LIN-14 transcription factor likely directly represses dma-1 gene expression through a transcriptional means, whereas the LIN-41 tripartite motif protein likely indirectly promotes dma-1 gene expression through a posttranscriptional means.


Subject(s)
Caenorhabditis elegans Proteins , MicroRNAs , Animals , Caenorhabditis elegans Proteins/metabolism , Caenorhabditis elegans/metabolism , Gene Expression Regulation, Developmental , Nociceptors/metabolism , MicroRNAs/genetics , MicroRNAs/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism , Tripartite Motif Proteins/genetics , Neuronal Plasticity , Repressor Proteins/metabolism , Membrane Proteins/metabolism
3.
J Am Chem Soc ; 146(25): 16996-17002, 2024 Jun 26.
Article in English | MEDLINE | ID: mdl-38875709

ABSTRACT

A highly regio- and enantioselective hydrosulfonylation using commercially available sodium sulfinates is reported, providing the first direct asymmetric rhodium-catalyzed hydrosulfonylation of allenes/alkynes to synthesize chiral allylic sulfones. Ligand screening studies demonstrated the indispensable role of the C1-symmetric P,N-ligand (Rax,S,S)-StackPhim for achieving both high regioselecitivity (>20:1) and enantioselectivity (up to 97% ee). Notably, the operationally simple method and mild conditions allow for the rapid preparation of chiral allylic sulfones with a wide scope of functional groups. Moreover, the use of sodium tert-butyldimethylsilyloxymethanesulfinate enables the collective synthesis of various chiral sulfone derivatives after simple transformations of the protected hydroxymethyl product.

4.
FASEB J ; 37(12): e23300, 2023 12.
Article in English | MEDLINE | ID: mdl-37997673

ABSTRACT

Primary cilium is a specialized sensory organelle that transmits environmental information into cells. Its length is tightly controlled by various mechanisms such as the frequency or the cargo size of the intraflagellar transport trains which deliver the building materials such as tubulin subunits essential for the growing cilia. Here, we show the sialoglycan interacting galectin 8 regulates the process of primary ciliogenesis. As the epithelia become polarized, there are more galectin 8 being apically secreted and these extracellular galectin 8 molecules apparently bind to a lipid raft enriched domain at the base of the primary cilia through interacting with lipid raft components, such as GD3 ganglioside and scaffold protein caveolin 1. Furthermore, the binding of galectin 8 at this critical region triggers rapid growth of primary cilia by perturbing the barrier function of the transition zone (TZ). Our study also demonstrates the functionality of this barrier depends on intact organization of lipid rafts at the cilia as genetically knockout of Cav1 and pharmacologically inhibition of lipid raft both phenocopy the effect of apical addition of recombinant galectin 8; that is, rapid elongation of primary cilia and redistribution of cilia proteins from TZ to the growing axoneme. Indeed, as cilia elongated, endogenous galectin 8, caveolin 1, and TZ component, TMEM231, also transited from the TZ to the growing axoneme. We also noted that the interaction between caveolin 1 and TMEM231 could be perturbed by exogenous galectin 8. Taken together, we proposed that galectin 8 promoted primary cilia elongation through impeding the barrier function of the TZ by interfering with the interaction between caveolin 1 and TMEM231.


Subject(s)
Caveolin 1 , Cilia , Caveolin 1/metabolism , Cilia/metabolism , Biological Transport , Tubulin/metabolism , Membrane Microdomains/metabolism
5.
Microsurgery ; 44(1): e31133, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37950581

ABSTRACT

BACKGROUND: In the field of head and neck microvascular reconstruction, no previous study has compared arterial and venous grafting as methods of anterolateral thigh (ALT) pedicle lengthening. Therefore, we conducted this comparative study to compare the outcomes between the two pedicle lengthening techniques. METHODS: We performed comparative effectiveness research by conducting a retrospective chart review from January 2012 to December 2021 to identify patients who underwent head and neck reconstruction with non-descending branch ALT perforator flaps using either the in situ pedicle lengthening (ISPL) technique or the vein graft (VG) technique. A total of 26 patients were analyzed, including 14 who underwent ISPL, and 12 who underwent VG. The collected data, including patient demographics, surgical indications, history of prior free flap, prior neck dissection, radiation therapy, chemotherapy, graft length, and flap outcomes, were analyzed. The flap outcomes were categorized as total flap loss, partial flap loss, flap compromise that required operating room visits, or minor issues, including infection or dehiscence. The flap characteristics and postoperative outcomes were compared between the two groups. RESULTS: The VG group had two flap losses, whereas the ISPL group had none. Although the failure rate was higher in the VG group than that in the ISPL group, the difference was not statistically significant (0% vs. 16.7%, p = 0.203). Additionally, there were no significant differences in flap take-back (14.3% vs. 16.7%, p = 1) and minor complications between the two groups (35.7% vs. 33.3%, p = 1). CONCLUSIONS: If pedicle lengthening with vessel graft is inevitable in head and neck reconstruction, arterial graft may provide a reliable outcome and may be considered an effective alternative when compared to vein grafts.


Subject(s)
Free Tissue Flaps , Head and Neck Neoplasms , Plastic Surgery Procedures , Humans , Retrospective Studies , Head and Neck Neoplasms/surgery , Neck/surgery , Free Tissue Flaps/blood supply , Postoperative Complications/etiology , Postoperative Complications/surgery , Thigh/surgery
6.
Medicina (Kaunas) ; 60(1)2024 Jan 04.
Article in English | MEDLINE | ID: mdl-38256358

ABSTRACT

This is a case report of Epstein-Barr virus (EBV) uveitis confirmed via aqueous humor polymerase chain reaction (PCR) and metagenomics. This 72-year-old male with a history of diabetes and herpes zoster complained of redness and blurred vision in his right eye for eight months. Mild conjunctival injection, anterior chamber cells, mutton-fat keratic precipitates, and vitreous haze were noted. Fluorescein angiography revealed dye leakage from retinal vessels without retinal ischemic changes. Only the serum anti-cytomegalovirus (CMV) IgG was positive while the aqueous humor PCR for VZV (Varicella-zoster virus), HSV (Herpes simplex viruses), CMV, and EBV was initially negative. Inflammation recurred and vitreous haze worsened after discontinuing nine-month topical ganciclovir and oral prednisolone. the aqueous humor PCR was repeated due to persistent low-grade inflammation. The EBV PCR turned out to be positive. Shotgun metagenomics revealed 1459 classified sequences (1.62%) and confirmed the EBV infection. Topical ganciclovir and methylprednisolone treatment was resumed. Conjunctival injection improved while pigmented keratic precipitates lessened. Elderly patients with diabetes or under immunosuppression may be susceptible to chronic uveitis associated with subsequent EBV infection. Repeated aqueous humor PCR and shotgun metagenomics are important tools in the diagnosis of this case of chronic indolent panuveitis.


Subject(s)
Cytomegalovirus Infections , Diabetes Mellitus , Epstein-Barr Virus Infections , Uveitis , Aged , Male , Humans , Herpesvirus 4, Human , Aqueous Humor , Uveitis/diagnosis , Uveitis/drug therapy , Inflammation , Antibodies, Viral , Ganciclovir/therapeutic use , Polymerase Chain Reaction
7.
J Synchrotron Radiat ; 30(Pt 6): 1135-1142, 2023 Nov 01.
Article in English | MEDLINE | ID: mdl-37850562

ABSTRACT

Synchrotron radiation can be used as a light source in X-ray microscopy to acquire a high-resolution image of a microscale object for tomography. However, numerous projections must be captured for a high-quality tomographic image to be reconstructed; thus, image acquisition is time consuming. Such dense imaging is not only expensive and time consuming but also results in the target receiving a large dose of radiation. To resolve these problems, sparse acquisition techniques have been proposed; however, the generated images often have many artefacts and are noisy. In this study, a deep-learning-based approach is proposed for the tomographic reconstruction of sparse-view projections that are acquired with a synchrotron light source; this approach proceeds as follows. A convolutional neural network (CNN) is used to first interpolate sparse X-ray projections and then synthesize a sufficiently large set of images to produce a sinogram. After the sinogram is constructed, a second CNN is used for error correction. In experiments, this method successfully produced high-quality tomography images from sparse-view projections for two data sets comprising Drosophila and mouse tomography images. However, the initial results for the smaller mouse data set were poor; therefore, transfer learning was used to apply the Drosophila model to the mouse data set, greatly improving the quality of the reconstructed sinogram. The method could be used to achieve high-quality tomography while reducing the radiation dose to imaging subjects and the imaging time and cost.

8.
Microb Ecol ; 85(1): 197-208, 2023 Jan.
Article in English | MEDLINE | ID: mdl-35034142

ABSTRACT

The 2,3,7,8-tetrachlorodibenzodioxin (TCDD), a contaminant in Agent Orange released during the US-Vietnam War, led to a severe environmental crisis. Approximately, 50Ā years have passed since the end of this war, and vegetation has gradually recovered from the pollution. Soil bacterial communities were investigated by 16S metagenomics in habitats with different vegetation physiognomies in Central Vietnam, namely, forests (S0), barren land (S1), grassland (S2), and developing woods (S3). Vegetation complexity was negatively associated with TCDD concentrations, revealing the reasoning behind the utilization of vegetation physiognomy as an indicator for ecological succession along the gradient of pollutants. Stark changes in bacterial composition were detected between S0 and S1, with an increase in Firmicutes and a decrease in Acidobacteria and Bacteroidetes. Notably, dioxin digesters Arthrobacter, Rhodococcus, Comamonadaceae, and Bacialles were detected in highly contaminated soil (S1). Along the TCDD gradients, following the dioxin decay from S1 to S2, the abundance of Firmicutes and Actinobacteria decreased, while that of Acidobacteria increased; slight changes occurred at the phylum level from S2 to S3. Although metagenomics analyses disclosed a trend toward bacterial communities before contamination with vegetation recovery, non-metric multidimensional scaling analysis unveiled a new trajectory deviating from the native state. Recovery of the bacterial community may have been hindered, as indicated by lower bacterial diversity in S3 compared to S0 due to a significant loss of bacterial taxa and recruitment of fewer colonizers. The results indicate that dioxins significantly altered the soil microbiomes into a state of disorder with a deviating trajectory in restoration.


Subject(s)
Dioxins , Microbiota , Polychlorinated Dibenzodioxins , Agent Orange , Soil , Polychlorinated Dibenzodioxins/analysis , Bacteria/genetics , Acidobacteria/genetics , Firmicutes , Soil Microbiology , RNA, Ribosomal, 16S/genetics
9.
BMC Psychiatry ; 23(1): 554, 2023 08 01.
Article in English | MEDLINE | ID: mdl-37528355

ABSTRACT

BACKGROUND: The treatment efficacy varies across individual patients with major depressive disorder (MDD). It lacks robust electroencephalography (EEG) markers for an antidepressant-responsive phenotype. METHOD: This is an observational study enrolling 28 patients with MDD and 33 healthy controls (mean age of 40.7 years, and 71.4% were women). Patients underwent EEG exams at baseline (week0) and week1, while controls' EEG recordings were acquired only at week0. A resting eye-closing EEG segment was analyzed for functional connectivity (FC). Four parameters were used in FC analysis: (1) node strength (NS), (2) global efficiency (GE), (3) clustering coefficient (CC), and (4) betweenness centrality (BC). RESULTS: We found that controls had higher values in delta wave in the indices of NS, GE, BC, and CC than MDD patients at baseline. After treatment with antidepressants, patients' FC indices improved significantly, including GE, mean CC, and mean NS in the delta wave. The FC in the alpha and beta bands of the responders were higher than those of the non-responders. CONCLUSIONS: The FC of the MDD patients at baseline without treatment was worse than that of controls. After treatment, the FC improved and was close to the values of controls. Responders showed better FC in the high-frequency bands than non-responders, and this feature exists in both pre-treatment and post-treatment EEG.


Subject(s)
Depressive Disorder, Major , Female , Male , Humans , Depressive Disorder, Major/therapy , Depression , Electroencephalography , Antidepressive Agents/therapeutic use , Biomarkers , Brain
10.
Cell Mol Life Sci ; 79(7): 367, 2022 Jun 19.
Article in English | MEDLINE | ID: mdl-35718818

ABSTRACT

Upregulation of death-domain-associated protein (Daxx) is strongly associated with diverse cancer types. Among these, the clinicopathological significance and molecular mechanisms of Daxx overexpression in colorectal cancer (CRC) remain unknown. Here, we showed that Daxx expression was increased in both clinical CRC samples and CRC cell lines. Daxx knockdown significantly reduced proliferation activity in CRC cells and tumor growth in a xenograft model. Further studies revealed that Daxx expression could be attenuated by either treatment with the PIK3CA inhibitor PIK-75 or PIK3CA depletion in CRC cells. Conversely, expression of PIK3CA constitutively active mutants could increase Daxx expression. These data suggest that PIK3CA positively regulates Daxx expression. Consistently, the expression levels of PIK3CA and Daxx were positively correlated in sporadic CRC samples. Interestingly, Daxx knockdown or overexpression yielded decreased or increased levels of PIK3CA, respectively, in CRC cells. We further demonstrated that Daxx activates the promoter activity and expression of PIK3CA. Altogether, our results identify a mechanistic pathway of Daxx overexpression in CRC and suggest a reciprocal regulation between Daxx and PIK3CA for CRC cell growth.


Subject(s)
Colorectal Neoplasms , Phosphatidylinositol 3-Kinases , Cell Line, Tumor , Cell Proliferation/genetics , Class I Phosphatidylinositol 3-Kinases/genetics , Co-Repressor Proteins/genetics , Co-Repressor Proteins/metabolism , Colorectal Neoplasms/metabolism , Gene Expression Regulation, Neoplastic , Humans , Molecular Chaperones/genetics , Molecular Chaperones/metabolism , Phosphatidylinositol 3-Kinases/genetics , Phosphatidylinositol 3-Kinases/metabolism
11.
Acta Cardiol Sin ; 39(3): 469-479, 2023 May.
Article in English | MEDLINE | ID: mdl-37229327

ABSTRACT

Pulmonary arterial hypertension (PAH) is a rare but severe complication of connective tissue disease (CTD). CTD-associated PAH (CTD-PAH) is the most common subgroup of PAH in East Asia. We prospectively collected 41 patients with CTD-PAH and followed them for a mean period of 43 Ā± 36 months. The long-term survival rates of the CTD-PAH patients at 1, 2, 3 and 5 years were 90%, 80%, 77%, and 60%, respectively. The non-survivors had more dilated main pulmonary arteries, higher pulmonary artery pressure and pulmonary vascular resistance (PVR). PAH-specific therapy resulted in improvements in functional class, 6-minute walk distance, serum uric acid, right ventricular function and PVR. Increased C-reactive protein during follow-up, indicating inflammatory processes, was also crucial for the management of CTD-PAH. Therefore targeting both PAH and inflammation is important in this specific subgroup of PAH. The results of this study may help develop treatment strategies for CTD-PAH patients.

12.
BMC Cancer ; 22(1): 413, 2022 Apr 15.
Article in English | MEDLINE | ID: mdl-35428225

ABSTRACT

BACKGROUND: This study was to determine the prevalence and clinical significance of clonal hematopoiesis (CH)-related variants, and somatic and germline mutations in cancer patients and healthy individuals. METHODS: We performed next-generation sequencing of 275 cancer-related genes be-tween plasma and white blood cells in 92 cancer patients and 47 controls without cancer. Blood samples were recruited from May 2017 to July 2021, and blood cancer patients were excluded. For all statistical analysis in this study, pĀ < 0.05 was considered statistically significant. RESULTS: Overall, 38.04% of patients and 46.81% of controls harbored at least one CH-related mutation in plasma cell-free DNA. Based on our results, older cancer patients exhibited a CH phenomenon more frequently than younger patients (p = 0.0024). A total of 39 somatic pathogenic (P)/likely pathogenic (LP) mutations were identified in 17 genes in 21 of 92 patients. We found that the presence of P/LP variants in cancer-related gene predicted shorter overall survival (OS) (p = 0.001). Multivariate analysis adjusted for CH-related mutations, germline mutations, and tumor stage, also indicated that somatic mutations correlated significantly with OS (p = 0.022). Moreover, the frequency of a germline P/LP variant was that of seven of 92 individuals in the cancer group and one of 42 individuals in the control group. CONCLUSIONS: We characterized the CH-related variants, and somatic and germline mutations in cancer patients and healthy individuals, and the results have important clinical significance.


Subject(s)
Germ-Line Mutation , Neoplasms , Humans , Liquid Biopsy , Mutation , Neoplasms/genetics , Oncogenes
13.
J Biomed Sci ; 29(1): 88, 2022 Oct 27.
Article in English | MEDLINE | ID: mdl-36303164

ABSTRACT

BACKGROUND: Owing to the heterogeneity of microbiota among individuals and populations, only Fusobacterium nucleatum and Bacteroides fragilis have been reported to be enriched in colorectal cancer (CRC) in multiple studies. Thus, the discovery of additional bacteria contributing to CRC development in various populations can be expected. We aimed to identify bacteria associated with the progression of colorectal adenoma to carcinoma and determine the contribution of these bacteria to malignant transformation in patients of Han Chinese origin. METHODS: Microbiota composition was determined through 16S rRNA V3-V4 amplicon sequencing of autologous adenocarcinomas, adenomatous polyps, and non-neoplastic colon tissue samples (referred to as "tri-part samples") in patients with CRC. Enriched taxa in adenocarcinoma tissues were identified through pairwise comparison. The abundance of candidate bacteria was quantified through genomic quantitative polymerase chain reaction (qPCR) in tissue samples from 116 patients. Associations of candidate bacteria with clinicopathological features and genomic and genetic alterations were evaluated through odds ratio tests. Additionally, the effects of candidate bacteria on CRC cell proliferation, migration, and invasion were evaluated through the co-culture of CRC cells with bacterial cells or with conditioned media from bacteria. RESULTS: Prevotella intermedia was overrepresented in adenocarcinomas compared with paired adenomatous polyps. Furthermore, co-abundance of P. intermedia and F. nucleatum was observed in tumor tissues. More notably, the coexistence of these two bacteria in adenocarcinomas was associated with lymph node involvement and distant metastasis. These two bacteria also exerted additive effects on the enhancement of the migration and invasion abilities of CRC cells. Finally, conditioned media from P. intermedia promoted the migration and invasion of CRC cells. CONCLUSION: This report is the first to demonstrate that P. intermedia is enriched in colorectal adenocarcinoma tissues and enhances the migration and invasion abilities of CRC cells. Moreover, P. intermedia and F. nucleatum exert additive effects on the malignant transformation of colorectal adenomas into carcinomas. These findings can be used to identify patients at a high risk of malignant transformation of colorectal adenomas or metastasis of CRC, and they can accordingly be provided optimal clinical management.


Subject(s)
Adenocarcinoma , Adenoma , Adenomatous Polyps , Colorectal Neoplasms , Humans , Fusobacterium nucleatum/genetics , Prevotella intermedia/genetics , RNA, Ribosomal, 16S/genetics , Culture Media, Conditioned , Adenoma/genetics , Adenoma/microbiology , Adenoma/pathology , Colorectal Neoplasms/pathology , Cell Transformation, Neoplastic/genetics , Bacteria/genetics , Adenocarcinoma/genetics , Adenomatous Polyps/genetics
14.
Org Biomol Chem ; 20(31): 6193-6195, 2022 08 10.
Article in English | MEDLINE | ID: mdl-35467680

ABSTRACT

Described is a total synthesis of racemic mersicarpine from diethyl 4-oxopimelate. The synthetic route takes advantage of a 2-indolyl radical cyclization to construct the pyrido[1,2-a]indole scaffold bearing the all-carbon quaternary stereocenter.


Subject(s)
Indole Alkaloids , Cyclization , Molecular Structure , Stereoisomerism
15.
Bioessays ; 42(8): e1900185, 2020 08.
Article in English | MEDLINE | ID: mdl-32529675

ABSTRACT

Axon regeneration is a conserved process across the animal kingdom. Recent studies using the soil worm Caenorhabditis elegans as a model system revealed that machineries regulating engulfment of dying cells also control axon regeneration and axon debris removal. In this review, the relationships between the engulfment machinery and the biological processes triggered by axon injury and subsequent axon regeneration drawn from divergent views are examined. In one study, it is found that engulfing cells directly promote axon regeneration. In this context, CED-1 (Drosophila Draper/mouse MEGF10), an engulfment protein expressed on the surface of engulfing cells, functions as a receptor for axon debris removal and as an adhesion molecule for axon regeneration. In other studies, it is shown that those engulfment genes, previously known to function within the engulfing cells for cell corpse removal, can have a cell-autonomous "non-engulfing cell" role in axon regeneration. Together, these findings suggest that engulfment genes are repurposed for neuronal regeneration by acting in both engulfing cells and regenerating neurons.


Subject(s)
Caenorhabditis elegans Proteins , Caenorhabditis elegans , Animals , Apoptosis , Axons , Caenorhabditis elegans/genetics , Caenorhabditis elegans Proteins/genetics , Membrane Proteins , Mice , Nerve Regeneration , Neurons
16.
Proc Natl Acad Sci U S A ; 116(50): 25137-25146, 2019 12 10.
Article in English | MEDLINE | ID: mdl-31767767

ABSTRACT

Stochastic neuronal cell fate choice involving notch-independent mechanisms is a poorly understood biological process. The Caenorhabditis elegans AWC olfactory neuron pair asymmetrically differentiates into the default AWCOFF and induced AWCON subtypes in a stochastic manner. Stochastic choice of the AWCON subtype is established using gap junctions and SLO BK potassium channels to repress a calcium-activated protein kinase pathway. However, it is unknown how the potassium channel-repressed calcium signaling is translated into the induction of the AWCON subtype. Here, we identify a detailed working mechanism of how the homeodomain-like transcription factor NSY-7, previously described as a repressor in the maintenance of AWC asymmetry, couples SLO BK potassium channels to transactivation of sox-2 expression for the induction of the AWCON subtype through the identification of a unique imb-2 (transportin 1) allele. imb-2 loss-of-function mutants are not viable; however, we identify a viable imb-2 allele from an unbiased forward genetic screen that reveals a specific role of imb-2 in AWC olfactory neuron asymmetry. IMB-2 specifically drives nuclear import of NSY-7 within AWC neurons to transactivate the expression of the high mobility group (HMG)-box transcription factor SOX-2 for the specification of the AWCON subtype. This study provides mechanistic insight into how NSY-7 couples SLO BK potassium channels to transactivation of sox-2 expression for the induction of the AWCON subtype. Our findings also provide structure-function insight into a conserved amino acid residue of transportins in brain development and suggest its dysfunction may lead to human neurological disorders.


Subject(s)
Cell Nucleus/metabolism , Karyopherins/metabolism , Olfactory Receptor Neurons/metabolism , SOXB1 Transcription Factors/metabolism , Animals , Caenorhabditis elegans/genetics , Caenorhabditis elegans/physiology , Caenorhabditis elegans Proteins/genetics , Caenorhabditis elegans Proteins/metabolism , Calcium Signaling/physiology , Gap Junctions/metabolism , Karyopherins/genetics , SOXB1 Transcription Factors/genetics , Stochastic Processes
17.
Cell Biol Int ; 45(11): 2347-2356, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34314079

ABSTRACT

Tazarotene-induced gene 1 (TIG1) is considered to be a tumor suppressor gene that is highly expressed in normal or well-differentiated colon tissues, while downregulation of TIG1 expression occurs in poorly differentiated colorectal cancer (CRC) tissues. However, it is still unclear how TIG1 regulates the tumorigenesis of CRC. Polo-like kinases (Plks) are believed to play an important role in regulating the cell cycle. The performance of PLK2 in CRC is negatively correlated with the differentiation status of CRC tissues. Here, we found that PLK2 can induce the growth of CRC cells and that TIG1 can prevent PLK2 from promoting the proliferation of CRC cells. We also found that the expression of PLK2 in CRC cells was associated with low levels of Fbxw7 protein and increased expression of cyclin E1. When TIG1 was coexpressed with PLK2, the changes in Fbxw7/cyclin E1 levels induced by PLK2 were reversed. In contrast, silencing TIG1 promoted the proliferation of CRC, and when PLK2 was also silenced, the proliferation of CRC cells induced by TIG1 silencing was significantly inhibited. The above research results suggest that TIG1 can regulate the tumorigenesis of CRC by regulating the activity of PLK2.


Subject(s)
Colorectal Neoplasms/genetics , Membrane Proteins/genetics , Protein Serine-Threonine Kinases/metabolism , Cell Cycle/genetics , Cell Cycle Proteins/genetics , Cell Division/genetics , Cell Proliferation/genetics , Colorectal Neoplasms/metabolism , Cyclin E/genetics , F-Box-WD Repeat-Containing Protein 7/genetics , Gene Silencing/physiology , HCT116 Cells , Humans , Membrane Proteins/metabolism , Oncogene Proteins/genetics , Protein Serine-Threonine Kinases/genetics , Proto-Oncogene Proteins/genetics , Polo-Like Kinase 1
18.
Int J Hyperthermia ; 38(1): 1322-1332, 2021.
Article in English | MEDLINE | ID: mdl-34477032

ABSTRACT

INTRODUCTION: The radiofrequency ablation (RFA) of liver cancer is a desirable treatment option, as it is minimally invasive. An accurate numerical simulation can greatly help physicians better plan their surgical protocols. Previously, the displacement current in the RFA process was considered negligible, and therefore RFA simulation was modeled as a direct current (DC) system instead of an alternating current (AC) system. Our study investigated the hypothesis that the displacement current in the RFA process should not always be considered negligible. METHODS: AC measurements of ex vivo bovine liver ablation were performed, and numerical simulations were also conducted to test the hypothesis that the relative permittivity would significantly decrease after the liver tissue reached a high temperature. RESULTS: The displacement current was observed to be a sizable fraction of the conduction current, especially before the onset of the first pause. The simulation results indicated that the relative permittivity is likely to decrease to several hundred or lower at elevated temperatures. CONCLUSIONS: Our study results suggest that the DC model may be inadequate, especially before the first roll-off and that additional information could be available during RFA treatment by considering the AC nature of RFA, which could lead to improved numerical simulation. Additional measurements of tissue parameters are needed to reach the full potential of the AC model for further development of ablation control.


Subject(s)
Catheter Ablation , Liver Neoplasms , Radiofrequency Ablation , Animals , Cattle , Computer Simulation , Liver/surgery , Liver Neoplasms/surgery
20.
BMC Microbiol ; 20(1): 365, 2020 11 27.
Article in English | MEDLINE | ID: mdl-33246404

ABSTRACT

BACKGROUND: Bacterial cultures allow the identification of infectious disease pathogens. However, obtaining the results of conventional culture methods is time-consuming, taking at least two days. A more efficient alternative is the use of concentrated bacterial samples to accelerate culture growth. Our study focuses on the development of a high-yield sample concentrating technique. RESULTS: A total of 71 paired samples were obtained from patients on peritoneal dialysis (PD). The peritoneal dialysates were repeat-centrifuged and then washed with saline, namely the centrifuging and washing method (C&W method). The concentrated samples were Gram-stained and inoculated into culture plates. The equivalent unprocessed dialysates were cultured as the reference method. The times until culture results for the two methods were compared. The reference method yielded no positive Gram stain results, but the C&W method immediately gave positive Gram stain results for 28 samples (p < 0.001). The culture-negative rate was lower in the C&W method (5/71) than in the reference method (13/71) (p = 0.044). The average time for bacterial identification achieved with the C&W method (22.0 h) was shorter compared to using the reference method (72.5 h) (p < 0.001). CONCLUSIONS: The C&W method successfully concentrated bacterial samples and superseded blood culture bottles for developing adequate bacterial cultures. The C&W method may decrease the culture report time, thus improving the treatment of infectious diseases.


Subject(s)
Bacteria/isolation & purification , Bacteriological Techniques/methods , Peritoneal Dialysis , Ascites/microbiology , Bacteria/classification , Bacteria/growth & development , Dialysis Solutions , Humans , Peritoneal Dialysis/adverse effects , Peritonitis/etiology , Peritonitis/microbiology , Specimen Handling , Time Factors
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