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1.
Development ; 149(11)2022 06 01.
Article in English | MEDLINE | ID: mdl-35587122

ABSTRACT

The sperm flagellum is essential for male fertility, and defects in flagellum biogenesis are associated with male infertility. Deficiency of coiled-coil domain-containing (CCDC) 42 (CCDC42) is specifically associated with malformation of mouse sperm flagella. Here, we find that the testis-specific protein CCDC38 interacts with CCDC42, localizing on the manchette and sperm tail during spermiogenesis. Inactivation of CCDC38 in male mice results in a distorted manchette, multiple morphological abnormalities of the flagella of spermatozoa and eventually male sterility. Furthermore, we find that CCDC38 interacts with intraflagellar transport protein 88 (IFT88), as well as outer dense fibrous 2 (ODF2), and the knockout of Ccdc38 reduces transport of ODF2 to the flagellum. Altogether, our results uncover the essential role of CCDC38 in sperm flagellum biogenesis, and suggest that some mutations of these genes might be associated with male infertility in humans.


Subject(s)
Fertility , Infertility, Male , Sperm Tail , Animals , Fertility/genetics , Heat-Shock Proteins/metabolism , Infertility, Male/genetics , Infertility, Male/metabolism , Male , Mice , Mice, Knockout , Sperm Tail/metabolism , Spermatozoa/metabolism , Testis/metabolism
2.
Nucleic Acids Res ; 51(14): 7357-7375, 2023 08 11.
Article in English | MEDLINE | ID: mdl-37378420

ABSTRACT

DNA-RNA hybrids play various roles in many physiological progresses, but how this chromatin structure is dynamically regulated during spermatogenesis remains largely unknown. Here, we show that germ cell-specific knockout of Rnaseh1, a specialized enzyme that degrades the RNA within DNA-RNA hybrids, impairs spermatogenesis and causes male infertility. Notably, Rnaseh1 knockout results in incomplete DNA repair and meiotic prophase I arrest. These defects arise from the altered RAD51 and DMC1 recruitment in zygotene spermatocytes. Furthermore, single-molecule experiments show that RNase H1 promotes recombinase recruitment to DNA by degrading RNA within DNA-RNA hybrids and allows nucleoprotein filaments formation. Overall, we uncover a function of RNase H1 in meiotic recombination, during which it processes DNA-RNA hybrids and facilitates recombinase recruitment.


Subject(s)
Meiosis , Ribonuclease H , Humans , Male , Cell Cycle Proteins/genetics , Cell Cycle Proteins/metabolism , DNA/genetics , DNA/metabolism , Rad51 Recombinase/genetics , Rad51 Recombinase/metabolism , Recombinases/genetics , Spermatocytes/metabolism , Ribonuclease H/metabolism
3.
Biochem Biophys Res Commun ; 735: 150428, 2024 Jul 20.
Article in English | MEDLINE | ID: mdl-39094231

ABSTRACT

Primary ciliary dyskinesia (PCD) is a group of genetically heterogeneous disorders characterized by clinical manifestations resulting from abnormal ciliary motility. Mutations in critical genes, such as Cyclin O (CCNO), have been associated with severe respiratory disease, though limited data are currently available. Here we show that CCNO deficient ciliated cells can only form a reduced number of fully functional centrioles that can mature into ciliated basal bodies, and their transport and anchoring to the top of the plasma membrane are abnormal. Furthermore, we observed that CCNO localizes not only in the cytoplasm but also in the nucleus during the early stages of ciliogenesis, and this dual localization persists into adulthood. Transcriptome analysis revealed downregulation of genes involved in cilia assembly and movement, along with altered transcription factors associated with ciliation upon CCNO depletion. These findings indicate that CCNO may serve as a key regulator in the transcriptional regulation of multiciliogenesis.

4.
Microcirculation ; 31(6): e12874, 2024 08.
Article in English | MEDLINE | ID: mdl-39011763

ABSTRACT

Shock is characterized with vascular hyporesponsiveness to vasoconstrictors, thereby to cause refractory hypotension, insufficient tissue perfusion, and multiple organ dysfunction. The vascular hyporeactivity persisted even though norepinephrine and fluid resuscitation were administrated, it is of critical importance to find new potential target. Ion channels are crucial in the regulation of cell membrane potential and affect vasoconstriction and vasodilation. It has been demonstrated that many types of ion channels including K+ channels, Ca2+ permeable channels, and Na+ channels exist in vascular smooth muscle cells and endothelial cells, contributing to the regulation of vascular homeostasis and vasomotor function. An increasing number of studies suggested that the structural and functional alterations of ion channels located in arteries contribute to vascular hyporesponsiveness during shock, but the underlying mechanisms remained to be fully clarified. Therefore, the expression and functional changes in ion channels in arteries associated with shock are reviewed, to pave the way for further exploring the potential of ion channel-targeted compounds in treating refractory hypotension in shock.


Subject(s)
Ion Channels , Shock , Humans , Shock/physiopathology , Shock/metabolism , Animals , Ion Channels/metabolism , Vasoconstriction/physiology , Muscle, Smooth, Vascular/metabolism , Muscle, Smooth, Vascular/physiopathology , Vasodilation/physiology , Hypotension/physiopathology , Hypotension/metabolism
5.
Cell Mol Life Sci ; 81(1): 1, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-38038747

ABSTRACT

Multiple morphological abnormalities of the flagella (MMAF) is a severe disease of male infertility, while the pathogenetic mechanisms of MMAF are still incompletely understood. Previously, we found that the deficiency of Ccdc38 might be associated with MMAF. To understand the underlying mechanism of this disease, we identified the potential partner of this protein and found that the coiled-coil domain containing 146 (CCDC146) can interact with CCDC38. It is predominantly expressed in the testes, and the knockout of this gene resulted in complete infertility in male mice but not in females. The knockout of Ccdc146 impaired spermiogenesis, mainly due to flagellum and manchette organization defects, finally led to MMAF-like phenotype. Furthermore, we demonstrated that CCDC146 could interact with both CCDC38 and CCDC42. It also interacts with intraflagellar transport (IFT) complexes IFT88 and IFT20. The knockout of this gene led to the decrease of ODF2, IFT88, and IFT20 protein levels, but did not affect CCDC38, CCDC42, or ODF1 expression. Additionally, we predicted and validated the detailed interactions between CCDC146 and CCDC38 or CCDC42, and built the interaction models at the atomic level. Our results suggest that the testis predominantly expressed gene Ccdc146 is essential for sperm flagellum biogenesis and male fertility, and its mutations might be associated with MMAF in some patients.


Subject(s)
Infertility, Male , Microtubule-Associated Proteins , Sperm Tail , Animals , Male , Mice , Fertility/genetics , Heat-Shock Proteins/metabolism , Infertility, Male/metabolism , Mice, Knockout , Semen , Sperm Tail/metabolism , Sperm Tail/pathology , Spermatozoa/metabolism , Testis/metabolism , Microtubule-Associated Proteins/genetics
6.
BMC Endocr Disord ; 21(1): 179, 2021 Sep 03.
Article in English | MEDLINE | ID: mdl-34479513

ABSTRACT

BACKGROUND: Rash and cholestatic liver injury caused by methimazole (MMI) in patients with Turner syndrome (TS) and Graves's disease (GD) are rarely reported, and there is a paucity of reports on the management of this condition. It is not clear whether propylthiouracil (PTU) can be used as a safe alternative in this case. CASE PRESENTATION: A 37-year-old woman was admitted to our hospital with rash, severe pruritus and a change in urine colour after 2 months of GD treatment with MMI. Physical examination showed rash scattered over the limbs and torso, mild jaundice of the sclera and skin, short stature, facial moles, immature external genitals and diffuse thyroid gland enlargement. Liver function tests indicated an increase in total bilirubin, direct bilirubin, total bile acid, glutamic pyruvic transaminase, glutamic oxaloacetic transaminase and alkaline phosphatase. The level of sex hormones suggested female hypergonadotropic hypogonadism. The karyotype of peripheral blood was 46, X, i(X)(q10)/45, X. After excluding biliary obstruction and other common causes of liver injury, combined with rash and abnormal liver function following oral administration of MMI, the patient was diagnosed as having TS with GD and rash and cholestatic liver injury caused by MMI. MMI was immediately discontinued, and eleven days after treatment with antihistamine and hepatoprotective agents was initiated, the rash subsided, and liver function returned to nearly normal. Because the patient did not consent to administration of 131I or thyroid surgery, hyperthyroidism was successfully controlled with PTU. No adverse drug reactions were observed after switching to PTU. CONCLUSIONS: While patients with TS and GD are undergoing treatment with MMI, their clinical manifestations, liver functions, and other routine blood test results should be closely monitored. When patients with TS and GD manifest adverse reactions to MMI such as rash and cholestatic liver injury, it is necessary to discontinue MMI and treat with antihistamine and hepatoprotective agents. After the rash subsides and liver function returns to nearly normal, PTU can effectively control hyperthyroidism without adverse drug reactions.


Subject(s)
Chemical and Drug Induced Liver Injury/pathology , Cholestasis/pathology , Exanthema/pathology , Graves Disease/drug therapy , Methimazole/adverse effects , Turner Syndrome/drug therapy , Adult , Antithyroid Agents/adverse effects , Chemical and Drug Induced Liver Injury/etiology , Cholestasis/etiology , Exanthema/etiology , Female , Graves Disease/complications , Graves Disease/pathology , Humans , Prognosis , Turner Syndrome/complications , Turner Syndrome/pathology
7.
Conscious Cogn ; 92: 103130, 2021 07.
Article in English | MEDLINE | ID: mdl-34023646

ABSTRACT

Previous studies have found that repeatedly exposed to a threatening situation may reduce doctors' level of empathy, reducing psychological stress and avoiding burnout and compassion fatigue. However, many essential studies found that it does not seem universal but rather modulated by group membership. In this study, we recorded event-related potentials (ERP) when doctors and controls watched visual stimuli describing patients attacking doctors (Threat events) or shaking hands with doctors (Neutral events). The present study showed an early N190 and a later centro-parietal P3 differential amplitude between threat stimuli and neutral stimuli were observed in the controls. For the doctors, there was such ERP differentiation in early N190. However, later stage P3 differential amplitude was not observed. The current research suggests that doctors could regulate empathy and avoid allocating more attention resources when processing social threats to ensure treatment efficiency and avoid burnout.


Subject(s)
Electroencephalography , Empathy , Cognition , Evoked Potentials , Humans , Stress, Psychological
8.
Molecules ; 23(6)2018 May 31.
Article in English | MEDLINE | ID: mdl-29857514

ABSTRACT

Panax ginseng is well known for its medicinal functions. As a class of important compound of ginseng, ginsenoside is widely studied around the world. In addition, ginseng glycopeptides also showed good biological activity, but researches in this field are rarely reported. In this study, ginseng glycopeptides (Gg) were first prepared from Panax ginseng by reflux extracted with 85% ethanol and the following purification with Sephadex G-15 column. Then, the inflammatory pain models induced by carrageenan and the rat pain models induced by Faure Marin were established for research on mechanism of analgesic activities. It is showed that Gg had an obvious inhibiting effect on inflammation and a significant reduction on the Malondialdehyde (MDA) of inflammatory foot tissue. And there were significant differences between moderate to high dose of Gg and model group in Interleukin 1ß (IL-1ß), Interleukin 2 (IL-2), Interleukin 4 (IL-4), Tumor necrosis factor α (TNF-α) and Histamine. The two models can be preliminarily determined that the analgesic effect of Gg may be peripheral, which mechanism may be related to the dynamic balance between proinflammatory cytokines (TNF-α, IL-1ß) and anti-inflammatory cytokines (IL-2, IL-4, and Interleukin 10 (IL-10)). A series of methods were used to study Gg in physical-chemical properties and linking mode of glycoside. The high-resolution mass spectrometry was used for identification of the structure of Gg. Moreover, the structure of 20 major Gg were investigated and identified. The structural analysis of Gg was benefit for the next study on structure-activity relationship.


Subject(s)
Analgesics/chemistry , Analgesics/pharmacology , Anti-Inflammatory Agents/chemistry , Anti-Inflammatory Agents/pharmacology , Glycopeptides/chemistry , Glycopeptides/pharmacology , Panax/chemistry , Animals , Carrageenan/chemistry , Carrageenan/pharmacology , Cytokines/metabolism , Disease Models, Animal , Inflammation Mediators/metabolism , Male , Methylation , Molecular Structure , Pain/etiology , Pain Management , Rats , Structure-Activity Relationship , Tandem Mass Spectrometry
9.
Br J Cancer ; 116(5): 658-668, 2017 Feb 28.
Article in English | MEDLINE | ID: mdl-28141796

ABSTRACT

BACKGROUND: DNA methylation at the 5 position of cytosine (5mC) can be converted to 5-hydroxymethylcytosine (5hmC) by the ten-eleven translocation family. The loss of global levels of 5hmC has been regarded as a hallmark in various cancers. 5-hydroxymethylcytosine is distributed at protein-coding gene bodies and promoters; however, the role and distribution of 5hmC at long non-coding RNAs (lncRNAs) is not clear. We investigated the distribution and regulatory roles of 5hmC for lncRNAs in colorectal cancer (CRC). METHODS: We integrated genome-wide profiles of 5hmC, 5mC, transcriptome and histone marks in CRC patients and examined the 5hmC-based clinical outcomes in patients. RESULTS: 5-hydroxymethylcytosine was distributed at lncRNA loci and positively correlated with lncRNA transcription. Dysreulated CRC lncRNAs were regulated by 5hmC directly or through abnormal activities of typical and super-enhancers and promoters modified by 5hmC. In addition, 5hmC was involved in long-range chromatin interactions at lncRNA loci. Finally, lncRNAs regulated by differential 5hmC marks were correlated with different clinical outcomes and tumour status in patients. CONCLUSIONS: 5-hydroxymethylcytosine is critical in regulating the transcription of lncRNA and serve as novel biomarkers for clinical prognosis in CRC.


Subject(s)
5-Methylcytosine/analogs & derivatives , Colorectal Neoplasms/pathology , Epigenomics/methods , RNA, Long Noncoding/genetics , 5-Methylcytosine/metabolism , Colorectal Neoplasms/genetics , DNA Methylation , Gene Expression Regulation, Neoplastic , Humans , Prognosis , Survival Analysis
10.
Zhongguo Dang Dai Er Ke Za Zhi ; 16(3): 272-6, 2014 Mar.
Article in Zh | MEDLINE | ID: mdl-24661520

ABSTRACT

OBJECTIVE: To evaluate the efficacy and safety of ribavirin aerosol in children with hand-foot-mouth disease (HFMD). METHODS: A randomized, double-blind, placebo-controlled trial was performed. A total of 119 children with mild HFMD were randomly divided into an observed group (n=59) and a control group (n=60). In the observed group, ribavirin aerosol was given four times within the first hour, followed by once every other hour for the remaining time of the day and day 2; from days 3 to 7, it was given 4 times per day, with 2-3 sprays every time, for 7 days. In the control group, placebo was given in the same way as in the observed group. Additionally, both groups used oral antiviral liquid. The scores of clinical symptoms including oral ulcer, skin rash, nasal congestion, runny nose, sneezing, cough, and fever before and after treatment were recorded to evaluate treatment outcomes. Throat swabs were taken before treatment and 5-7 days after treatment to measure viral load by RT-PCR and to compare the negative conversion rate between the two groups. RESULTS: Fifty-seven patients in the observed group and 56 patients in the control group were tested according to the original research design. After 5-7 days of treatment, the observed group had a significantly higher overall negative conversion rate of enterovirus than the control group (P<0.01). The overall marked response rate and overall response rate of the observed group were 89% and 89%, respectively, significantly higher than those of the control group (29% and 43%). During treatment, there were no adverse reactions such as dizziness, vomiting, and notable decreases in hemoglobin, white blood cells, and platelets in the two groups. CONCLUSIONS: Ribavirin aerosol can be effectively and safely used for treating mild HFMD. With low dosage and few adverse reactions, it holds promise for clinical application.


Subject(s)
Antiviral Agents/therapeutic use , Hand, Foot and Mouth Disease/drug therapy , Ribavirin/therapeutic use , Aerosols , Child , Child, Preschool , Double-Blind Method , Female , Humans , Infant , Infant, Newborn , Male , Ribavirin/administration & dosage , Ribavirin/adverse effects
11.
Nanomicro Lett ; 16(1): 279, 2024 Sep 03.
Article in English | MEDLINE | ID: mdl-39225896

ABSTRACT

The new-generation electronic components require a balance between electromagnetic interference shielding efficiency and open structure factors such as ventilation and heat dissipation. In addition, realizing the tunable shielding of porous shields over a wide range of wavelengths is even more challenging. In this study, the well-prepared thermoplastic polyurethane/carbon nanotubes composites were used to fabricate the novel periodic porous flexible metamaterials using fused deposition modeling 3D printing. Particularly, the investigation focuses on optimization of pore geometry, size, dislocation configuration and material thickness, thus establishing a clear correlation between structural parameters and shielding property. Both experimental and simulation results have validated the superior shielding performance of hexagon derived honeycomb structure over other designs, and proposed the failure shielding size (Df ≈λ/8 - λ/5) and critical inclined angle (θf ≈43° - 48°), which could be used as new benchmarks for tunable electromagnetic shielding. In addition, the proper regulation of the material thickness could remarkably enhance the maximum shielding capability (85 - 95 dB) and absorption coefficient A (over 0.83). The final innovative design of the porous shielding box also exhibits good shielding effectiveness across a broad frequency range (over 2.4 GHz), opening up novel pathways for individualized and diversified shielding solutions.

12.
Nanomicro Lett ; 16(1): 85, 2024 Jan 12.
Article in English | MEDLINE | ID: mdl-38214822

ABSTRACT

Electromagnetic interference shielding (EMI SE) modules are the core component of modern electronics. However, the traditional metal-based SE modules always take up indispensable three-dimensional space inside electronics, posing a major obstacle to the integration of electronics. The innovation of integrating 3D-printed conformal shielding (c-SE) modules with packaging materials onto core electronics offers infinite possibilities to satisfy ideal SE function without occupying additional space. Herein, the 3D printable carbon-based inks with various proportions of graphene and carbon nanotube nanoparticles are well-formulated by manipulating their rheological peculiarity. Accordingly, the free-constructed architectures with arbitrarily-customized structure and multifunctionality are created via 3D printing. In particular, the SE performance of 3D-printed frame is up to 61.4 dB, simultaneously accompanied with an ultralight architecture of 0.076 g cm-3 and a superhigh specific shielding of 802.4 dB cm3 g-1. Moreover, as a proof-of-concept, the 3D-printed c-SE module is in situ integrated into core electronics, successfully replacing the traditional metal-based module to afford multiple functions for electromagnetic compatibility and thermal dissipation. Thus, this scientific innovation completely makes up the blank for assembling carbon-based c-SE modules and sheds a brilliant light on developing the next generation of high-performance shielding materials with arbitrarily-customized structure for integrated electronics.

13.
Polymers (Basel) ; 16(10)2024 May 09.
Article in English | MEDLINE | ID: mdl-38794526

ABSTRACT

In this paper, the solid-state shear milling (S3M) strategy featuring a very strong three-dimensional shear stress field was adopted to prepare the high-performance polyoxymethylene (POM)/molybdenum disulfide (MoS2) functional nanocomposite. The transmission electron microscope and Raman measurement results confirmed that the bulk MoS2 particle was successfully exfoliated into few-layer MoS2 nanoplatelets by the above simple S3M physical method. The polarized optical microscope (PLM) observation indicated the pan-milled nanoscale MoS2 particles presented a better dispersion performance in the POM matrix. The results of the tribological test indicated that the incorporation of MoS2 could substantially improve the wear resistance performance of POM. Moreover, the pan-milled exfoliated MoS2 nanosheets could further substantially decrease the friction coefficient of POM. Scanning electron microscope observations on the worn scar revealed the tribological mechanism of the POM/MoS2 nanocomposite prepared by solid-state shear milling. The tensile test results showed that the pan-milled POM/MoS2 nanocomposite has much higher elongation at break than the conventionally melt-compounded material. The solid-state shear milling strategy shows a promising prospect in the preparation of functional nanocomposite with excellent comprehensive performance at a large scale.

14.
Adv Sci (Weinh) ; 11(13): e2306986, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38240347

ABSTRACT

Previously a ring finger protein 20 (RNF20) is found to be essential for meiotic recombination and mediates H2B ubiquitination during spermatogenesis. However, its role in meiotic division is still unknown. Here, it is shown that RNF20 is localized at both centromeres and spindle poles, and it is required for oocyte acentrosomal spindle organization and female fertility. RNF20-depleted oocytes exhibit severely abnormal spindle and chromosome misalignment caused by defective bipolar organization. Notably, it is found that the function of RNF20 in spindle assembly is not dependent on its E3 ligase activity. Instead, RNF20 regulates spindle assembly by recruiting tropomyosin3 (TPM3) to both centromeres and spindle poles with its coiled-coil motif. The RNF20-TPM3 interaction is essential for acentrosomal meiotic spindle assembly. Together, the studies uncover a novel function for RNF20 in mediating TPM3 recruitment to both centromeres and spindle poles during oocyte spindle assembly.


Subject(s)
Meiosis , Spindle Apparatus , Male , Female , Humans , Spindle Apparatus/metabolism , Oocytes/metabolism , Spindle Poles/metabolism , Centromere
15.
Polymers (Basel) ; 15(2)2023 Jan 10.
Article in English | MEDLINE | ID: mdl-36679255

ABSTRACT

In this study, a ternary hydrogen (H)-bonded complex intumescent flame retardant (TH-IFR) of melamine (ME) · phosphoric acid (PA)…pentaerythritol (PER) was synthesized through hydrothermal reaction. The combination of the synthesized TH-IFR with 4A molecular sieve as the synergist was used for the first time to improve the flame retardancy of polypropylene (PP). The involved structure, morphology, flame retardancy, flame-retarding mechanism and mechanical properties of the prepared PP composites were systematically investigated. The results show that incorporation of 1 wt% synergist 4A shows the optimum synergistic effect, and the flame retardancy and mechanical properties of the flame-retarded (FR) PP composites are significantly improved. Incorporation of 4A could change the pyrolysis process of the entire system and promote the char-forming chemical interaction, thereby further enhancing the flame retardancy of FR PP composite. The synergistically flame-retarding mechanism of 4A is explained by the significantly improved quality and quantity of the solid-phase char layer, which is formed through generation of SiO2 and Al2O3 substances, and also participation of PP macromolecular chains in the final char layer formation during burning. Furthermore, the improved dispersion and compatibility of TH-IFR in the composite is largely beneficial to the improvement of flame retardancy and mechanical properties.

16.
PeerJ ; 11: e15673, 2023.
Article in English | MEDLINE | ID: mdl-37551344

ABSTRACT

Background: Infertility is recognized as a common and worrisome problem of human reproduction worldwide. Based on previous studies, male factors account for about half of all infertility cases. Exposure to environmental toxicants is an important contributor to male infertility. Bisphenol A (BPA) is the most prominent toxic environmental contaminant worldwide affecting the male reproductive system. BPA can impair the function of the Golgi apparatus which is important in spermatogenesis. GGA1 is known as Golgi-localized, gamma adaptin ear-containing, ARF-binding protein 1. Previously, it has been shown that GGA1 is associated with spermatogenesis in Drosophila, however, its function in mammalian spermatogenesis remains unclear. Methods: Gga1 knockout mice were generated using the CRISPR/Cas9 system. Gga1-/- male mice and wild-type littermates received intraperitoneal (i.p.) injections of BPA (40 µg/kg) once daily for 2 weeks. Histological and immunofluorescence staining were performed to analyze the phenotypes of these mice. Results: Male mice lacking Gga1 had normal fertility without any obvious defects in spermatogenesis, sperm count and sperm morphology. Gga1 ablation led to infertility in male mice exposed to BPA, along with a significant reduction in sperm count, sperm motility and the percentage of normal sperm. Histological analysis of the seminiferous epithelium showed that spermatogenesis was severely disorganized, while apoptotic germ cells were significantly increased in the Gga1 null mice exposed to BPA. Our findings suggest that Gga1 protects spermatogenesis against damage induced by environmental pollutants.


Subject(s)
Adaptor Proteins, Vesicular Transport , Infertility, Male , Sperm Motility , Animals , Male , Mice , Infertility, Male/chemically induced , Semen , Spermatogenesis/genetics , Spermatozoa/metabolism , Adaptor Proteins, Vesicular Transport/genetics , Adaptor Proteins, Vesicular Transport/metabolism
17.
Polymers (Basel) ; 15(10)2023 May 09.
Article in English | MEDLINE | ID: mdl-37242809

ABSTRACT

Poly(lactic acid) (PLA) microneedles have been explored extensively, but the current regular fabrication strategy, such as thermoforming, is inefficient and poorly conformable. In addition, PLA needs to be modified as the application of microneedle arrays made of pure PLA is limited because of their easy tip fracture and poor skin adhesion. For this purpose, in this article, we reported a facile and scalable strategy to fabricate the microneedle arrays of the blend of PLA matrix and poly(p-dioxanone) (PPDO) dispersed phase with complementary mechanical properties through microinjection molding technology. The results showed that the PPDO dispersed phase could be in situ fibrillated under the effect of the strong shear stress field generated in micro-injection molding. These in situ fibrillated PPDO dispersed phases could hence induce the formation of the shish-kebab structures in the PLA matrix. Particularly for PLA/PPDO (90/10) blend, there are the densest and most perfect shish-kebab structures formed. The above microscopic structure evolution could be also advantageous to the enhancement in the mechanical properties of microparts of PLA/PPDO blend (tensile microparts and microneedle arrays), e.g., the elongation at break of the blend is almost double that of pure PLA while still maintaining the high stiffness (Young's modulus of 2.7 GPa) and the high strength (tensile strength of 68.3 MPa) in the tensile test, and relative to pure PLA, there is 100% or more increase in the load and displacement of microneedle in the compression test. This could open up new spaces for expanding the industrial application of the fabricated microneedle arrays.

18.
Elife ; 122023 10 17.
Article in English | MEDLINE | ID: mdl-37847146

ABSTRACT

The landscape of extrachromosomal circular DNA (eccDNA) during mammalian spermatogenesis, as well as the biogenesis mechanism, remains to be explored. Here, we revealed widespread eccDNA formation in human sperms and mouse spermatogenesis. We noted that germline eccDNAs are derived from oligonucleosomal DNA fragmentation in cells likely undergoing cell death, providing a potential new way for quality assessment of human sperms. Interestingly, small-sized eccDNAs are associated with euchromatin, while large-sized ones are preferentially generated from heterochromatin. By comparing sperm eccDNAs with meiotic recombination hotspots and structural variations, we found that they are barely associated with de novo germline deletions. We further developed a bioinformatics pipeline to achieve nucleotide-resolution eccDNA detection even with the presence of microhomologous sequences that interfere with precise breakpoint identification. Empowered by our method, we provided strong evidence to show that microhomology-mediated end joining is the major eccDNA biogenesis mechanism. Together, our results shed light on eccDNA biogenesis mechanism in mammalian germline cells.


Subject(s)
DNA, Circular , Semen , Male , Animals , Humans , Mice , DNA, Circular/genetics , Chromosomes , Spermatogenesis/genetics , Mammals/genetics
19.
ACS Biomater Sci Eng ; 9(12): 6734-6744, 2023 Dec 11.
Article in English | MEDLINE | ID: mdl-37939039

ABSTRACT

Poly(vinyl alcohol) (PVA) exhibits a wide range of potential applications in the biomedical field due to its favorable mechanical properties and biocompatibility. However, few studies have been carried out on selective laser sintering (SLS) of PVA due to its poor thermal processability. In this study, in order to impart PVA powder the excellent thermal processability, the molecular complexation technology was performed to destroy the strong hydrogen bonds in PVA and thus significantly reduced the PVA melting point and crystallinity to 190.9 °C and 27.9%, respectively. The modified PVA (MPVA) was then compounded with hydroxyapatite (HA) to prepare PVA/HA composite powders suitable for SLS 3D printing. The final SLS 3D-printed MPVA/HA composite porous scaffolds show high precision and interconnected pores with a porosity as high as 68.3%. The in vitro cell culture experiments revealed that the sintered composite scaffolds could significantly promote the adhesion and proliferation of osteoblasts and facilitate bone regeneration, and the quantitative real-time polymerase chain reaction results further demonstrate that the printed MPVA/20HA scaffold could significantly enhance the expression levels of both early osteogenic-specific marker of alkaline phosphatase stain and runt-related transcription factor 2. Meanwhile, in in vivo experiments, it is encouragingly found that the resultant MPVA/20HA SLS 3D-printed part has an obvious effect on promoting the growth of new bone tissue as well as a better bone regeneration capability. This work could provide a promising strategy for fabrication of PVA scaffolds through SLS 3D printing, exhibiting a great potential for clinical applications in bone tissue engineering.


Subject(s)
Durapatite , Tissue Scaffolds , Durapatite/pharmacology , Durapatite/chemistry , Tissue Scaffolds/chemistry , Porosity , Polyvinyl Alcohol/chemistry , Ethanol , Printing, Three-Dimensional
20.
Autophagy ; 19(2): 644-659, 2023 02.
Article in English | MEDLINE | ID: mdl-35786405

ABSTRACT

Primary ovarian insufficiency (POI), also known as premature ovarian failure, is an ovarian defect in humans characterized by the premature depletion of ovarian follicles before the age of 40. However, the mechanisms underlying POI remain largely unknown. Here, we show that knockout of Epg5 (ectopic P-granules autophagy protein 5 homolog (C. elegans)) results in subfertility in female mice, which exhibit a POI-like phenotype. Single-cell RNA sequencing analysis revealed that the knockout of Epg5 affected the differentiation of granulosa cells (GCs). Further investigation demonstrated that knockout of Epg5 blocks macroautophagic/autophagic flux, resulting in the accumulation of WT1 (WT1 transcription factor), an essential transcription factor for GCs, suggesting WT1 needs to be selectively degraded by the autophagy pathway. We found that the insufficient degradation of WT1 in the antral follicular stage contributes to reduced expression of steroidogenesis-related genes, thereby disrupting GC differentiation. Collectively, our studies show that EPG5 promotes WT1 degradation in GCs, indicating that the dysregulation of Epg5 in GCs can trigger POI pathogenesis.Abbreviations: 3-MA, 3-methyladenine; CHX, cycloheximide; CQ, chloroquine; EPG5, ectopic P-granules autophagy protein 5 homolog (C. elegans); GC, granulosa cell; MAP1LC3/LC3, microtubule-associated protein 1 light chain 3; MII, metaphase II; POI, primary ovarian insufficiency; PB1, polar body 1; SQSTM1/p62, sequestosome 1; WT1, WT1 transcription factor.


Subject(s)
Primary Ovarian Insufficiency , Animals , Female , Mice , Autophagy/genetics , Autophagy-Related Protein 5/metabolism , Autophagy-Related Proteins/metabolism , Caenorhabditis elegans/metabolism , Granulosa Cells/metabolism , Primary Ovarian Insufficiency/genetics , Primary Ovarian Insufficiency/metabolism , Primary Ovarian Insufficiency/pathology , Transcription Factors/metabolism , Vesicular Transport Proteins/metabolism , WT1 Proteins/genetics , WT1 Proteins/metabolism
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