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1.
Heliyon ; 10(9): e30015, 2024 May 15.
Article de Anglais | MEDLINE | ID: mdl-38707411

RÉSUMÉ

Here, we presented 6 patients who were admitted to our institution and diagnosed as myasthenia gravis (MG) with tongue muscle atrophy. All these 6 patients developed symptoms of bulbar muscle weakness in acetylcholine receptor antibodies positive MG (AChR-MG) (3/6), muscle-specific receptor tyrosine kinase antibodies positive MG (MuSK-MG) (1/6), and sero-negative MG (2/6). Most of patients had "triple-furrowed" tongue except for patient 2 with irregular atrophy of tongue muscle. Tongue muscle atrophy occurs in patients with MuSK-MG, AChR-MG, and sero-negative MG. Atrophied tongue muscles of five patients with MG were reversible after immunotherapy.

2.
Adv Healthc Mater ; 13(17): e2304136, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38551143

RÉSUMÉ

Oncolytic virus therapy is currently regarded as a promising approach in cancer immunotherapy. It has greater therapeutic advantages for colorectal cancer that is prone to distant metastasis. However, the therapeutic efficacy and clinical application of viral agents alone for colorectal cancer remain suboptimal. In this study, an engineered oncolytic vaccinia virus (OVV-Luc) that expresses the firefly luciferase gene is developed and loaded Chlorin e6 (Ce6) onto the virus surface through covalent coupling, resulting in OVV-Luc@Ce6 (OV@C). The OV@C infiltrates tumor tissue and induces endogenous luminescence through substrate catalysis, resulting in the production of reactive oxygen species. This unique system eliminates the need for an external light source, making it suitable for photodynamic therapy (PDT) in deep tissues. Moreover, this synergistic effect between PDT and viral immunotherapy enhances dendritic cell maturation, macrophage polarization, and reversal of the immunosuppressive microenvironment. This synergistic effect has the potential to convert a "cold" into a "hot" tumor, it offers valuable insights for clinical translation and application.


Sujet(s)
Tumeurs colorectales , Immunothérapie , Thérapie virale de cancers , Virus oncolytiques , Photothérapie dynamique , Virus de la vaccine , Virus de la vaccine/génétique , Virus de la vaccine/physiologie , Photothérapie dynamique/méthodes , Tumeurs colorectales/thérapie , Tumeurs colorectales/anatomopathologie , Animaux , Thérapie virale de cancers/méthodes , Virus oncolytiques/génétique , Virus oncolytiques/physiologie , Humains , Immunothérapie/méthodes , Souris , Chlorophyllides , Lignée cellulaire tumorale , Porphyrines/composition chimique , Porphyrines/pharmacologie , Souris de lignée BALB C , Association thérapeutique/méthodes , Espèces réactives de l'oxygène/métabolisme , Femelle
3.
Sci Eng Ethics ; 22(5): 1277-1284, 2016 10.
Article de Anglais | MEDLINE | ID: mdl-26276162

RÉSUMÉ

Human induced pluripotent stem cells can be obtained from somatic cells, and their derivation does not require destruction of embryos, thus avoiding ethical problems arising from the destruction of human embryos. This type of stem cell may provide an important tool for stem cell therapy, but it also results in some ethical concerns. It is likely that abnormal reprogramming occurs in the induction of human induced pluripotent stem cells, and that the stem cells generate tumors in the process of stem cell therapy. Human induced pluripotent stem cells should not be used to clone human beings, to produce human germ cells, nor to make human embryos. Informed consent should be obtained from patients in stem cell therapy.


Sujet(s)
Déontologie médicale , Cellules souches pluripotentes induites , Cellules souches pluripotentes , Thérapie cellulaire et tissulaire/éthique , Humains , Consentement libre et éclairé , Transplantation de cellules souches/éthique
4.
Mol Med Rep ; 11(4): 3115-21, 2015 Apr.
Article de Anglais | MEDLINE | ID: mdl-25502794

RÉSUMÉ

Tanshinone IIA is a lipophilic abietane diterpene compound, which exhibits protective effects against ischaemia/reperfusion injury; however, the pathways responsible for the myocardial protective activities of tanshinone IIA remain to be elucidated. The aim of the present study was to investigate the effect of tanshinone IIA on the Janus­activated kinase (JAK)/signal transducer and activator of transcription (STAT) signaling pathway, which is associated with cardiac dysfunction during ischemia/reperfusion. The results demonstrated that tanshinone IIA protected myocardial cells from hypoxia/ischemia­induced injury in vitro and recovered decreased cell viability due to activation of the JAK2/STAT3 pathway, with 10 µM tanshinone IIA exhibiting the most potent protective effects. Flow cytometric analysis revealed that tanshinone IIA reversed the apoptotic aggravation induced by JAK2/STAT3 inhibitors following hypoxic ischemia. However, JAK2 inhibitors promoted the myocardial protective effect of tanshinone IIA from hypoxic­ischemic injury. Furthermore, tanshinone IIA and JAK2/STAT3 inhibitors in combination augmented the protection of myocardial cells from apoptosis induced by ischemia/reperfusion preconditioning in vivo. In conclusion, the results of the present study indicated that JAK2/STAT3 inhibitors may enhance the protective effect of tanshinone IIA on cardiac myocytes from hypoxic ischemia-induced injury, therefore suggesting that JAK2/STAT3 inhibitors may have a potential application in combination therapies with tanshinone IIA.


Sujet(s)
Abiétanes/pharmacologie , Janus kinases/métabolisme , Lésion de reperfusion myocardique/métabolisme , Myocytes cardiaques/effets des médicaments et des substances chimiques , Myocytes cardiaques/métabolisme , Facteurs de transcription STAT/métabolisme , Animaux , Apoptose/effets des médicaments et des substances chimiques , Cardiotoniques/pharmacologie , Survie cellulaire/effets des médicaments et des substances chimiques , Modèles animaux de maladie humaine , Kinase Janus-2/antagonistes et inhibiteurs , Kinase Janus-2/métabolisme , Janus kinases/antagonistes et inhibiteurs , Mâle , Lésion de reperfusion myocardique/traitement médicamenteux , Lésion de reperfusion myocardique/anatomopathologie , Inhibiteurs de protéines kinases/pharmacologie , Rats , Facteurs de transcription STAT/antagonistes et inhibiteurs , Transduction du signal/effets des médicaments et des substances chimiques
5.
Acta Pharmacol Sin ; 34(11): 1386-96, 2013 Nov.
Article de Anglais | MEDLINE | ID: mdl-24077633

RÉSUMÉ

AIM: To investigate the mechanisms underlying the protective effects of sodium tanshinone IIA sulfonate (STS) in an ischemia-reperfusion (I/R)-induced rat myocardial injury model. METHODS: Male SD rats were iv injected with STS, STS+LY294002 or saline (NS) for 15 d. Then the hearts were subjected to 30 min of global ischemia followed by 2 h of reperfusion. Cardiac function, infarction size and area at risk were assessed. Cell apoptosis was evaluated with TUNEL staining, DNA laddering and measuring caspase-3 activity. In addition, isolated cardiomyocytes of neonatal rats were pretreated with the above drugs, then exposed to H2O2 (200 mol/L) for 1 h. Cell apoptosis was detected using flow cytometric assay. The levels of p-Akt, p-FOXO3A and Bim were examined with immunoblotting. RESULTS: Compared to NS group, administration of STS (20 mg/kg) significantly reduced myocardial infarct size (40.28%±5.36% in STS group vs 59.52%±7.28% in NS group), and improved the myocardial function as demonstrated by the increased values of dp/dtmax, LVDP and coronary flow at different reperfusion time stages. Furthermore, STS significantly decreased the rate of apoptotic cells (15.11%±3.71% in STS group vs 38.21%±7.83% in NS group), and reduced caspase-3 activity to nearly a quarter of that in NS group. Moreover, STS significantly increased the phosphorylation of Akt and its downstream target FOXO3A, and decreased the expression of pro-apoptotic gene Bim. Co-treatment with the PI3K inhibitor LY294002 (40 mg/kg) partially countered the protective effects induced by STS treatment. In isolated cardiomyocytes, STS exerted similar protective effects as shown in the ex vivo I/R model. CONCLUSION: STS pretreatment reduces infarct size and improves cardiac function in an I/R-induced rat myocardial injury model via activation of Akt/FOXO3A/Bim-mediated signal pathway.


Sujet(s)
Infarctus du myocarde/prévention et contrôle , Lésion de reperfusion myocardique/traitement médicamenteux , Myocytes cardiaques/effets des médicaments et des substances chimiques , Phénanthrènes/pharmacologie , Animaux , Animaux nouveau-nés , Apoptose/effets des médicaments et des substances chimiques , Protéines régulatrices de l'apoptose/métabolisme , Protéine-11 analogue à Bcl-2 , Cardiotoniques/pharmacologie , 4H-1-Benzopyran-4-ones/pharmacologie , Modèles animaux de maladie humaine , Cytométrie en flux , Protéine O3 à motif en tête de fourche , Facteurs de transcription Forkhead/métabolisme , Régulation de l'expression des gènes/effets des médicaments et des substances chimiques , Méthode TUNEL , Mâle , Protéines membranaires/métabolisme , Morpholines/pharmacologie , Infarctus du myocarde/étiologie , Lésion de reperfusion myocardique/complications , Myocytes cardiaques/métabolisme , Phosphatidylinositol 3-kinases/métabolisme , Protéines proto-oncogènes/métabolisme , Protéines proto-oncogènes c-akt/métabolisme , Rats , Rat Sprague-Dawley , Transduction du signal/effets des médicaments et des substances chimiques
6.
Zygote ; 21(3): 246-9, 2013 Aug.
Article de Anglais | MEDLINE | ID: mdl-21838965

RÉSUMÉ

Whale oocytes recovered from follicles can be matured in vitro. Whale sperm and mature oocytes can be used for in vitro fertilization (IVF), and IVF embryos have the ability to develop to morula stage. Whale sperm injected into bovine or mouse oocytes can activate the oocytes and form pronucleus. Interspecies somatic cell nuclear transfer embryos have been reconstructed with whale somatic cell nucleus and enucleated bovine or porcine oocytes, and interspecies cloned embryos can develop in vitro. This paper reviews recent progress in maturation, fertilization and development of whale oocytes.


Sujet(s)
Cryoconservation/méthodes , Fécondation in vitro , Ovocytes/physiologie , Baleines , Animaux , Bovins , Cellules cultivées , Femelle , Techniques de maturation in vitro des ovocytes , Mâle , Souris , Techniques de transfert nucléaire , Ovocytes/cytologie , Spermatozoïdes , Suidae
7.
Zygote ; 13(3): 249-53, 2005 Aug.
Article de Anglais | MEDLINE | ID: mdl-16261770

RÉSUMÉ

The injection of spermatozoa into mouse, human and rabbit oocytes at specific times and positions can result in different rates of viable embryo development. However, it is not clear how the timing and position of round spermatid injection (ROSI) affect pronucleus (PN) formation and blastocyst development of mice. First, we determined the changes in relative position of the first polar body and the spindle, carried out ROSI from 11.5 to 13 h post-hCG administration, then activated by Sr2+, and finally compared the development of ROSI zygotes, including the formation of pronuclei and development of blastocyst. Between 11.5 and 13 h post-hCG administration, the rate of 2PN formation by ROSI at 3 o'clock was the highest among all treated oocytes. Moreover, the blastocyst rate of zygotes with two pronuclei (2PN) was up to 27.41%. These results suggest that the time and position of ROSI can significantly influence the formation of 2PN, that the rates of 2PN formation are closely correlated with blastocyst formation and that the formation of 2PN is necessary for later embryo development.


Sujet(s)
Blastocyste/physiologie , Développement embryonnaire , Ovocytes/physiologie , Injections intracytoplasmiques de spermatozoïdes/méthodes , Spermatides , Zygote/croissance et développement , Animaux , Transfert d'embryon , Femelle , Mâle , Souris , Souris de lignée C57BL , Lignées consanguines de souris , Microinjections , Facteurs temps
8.
Reproduction ; 130(3): 359-66, 2005 Sep.
Article de Anglais | MEDLINE | ID: mdl-16123243

RÉSUMÉ

In this study, we investigated the development, the cell number of the blastocyst, and apoptosis in rabbit nuclear transfer (NT) embryos derived from adult fibroblasts and cumulus cells as compared with embryos derived from in vivo fertilization and in vitro culture. The developmental rate and the total cell number of the blastocyst were significantly lower in NT embryos than in fertilized embryos (FEs). The type of donor cells did not affect the embryonic developmental rate and the total cell number of blastocysts in NT groups. The present study investigated the onset and the frequency of apoptosis in NT embryos and FEs by using a terminal deoxynucleotidyl transferase-mediated dUTP nick and labeling (TUNEL) assay. The earliest positive TUNEL signals were detected at the eight-cell stage in NT embryos and at the morula stage in FEs. The apoptotic index of the total blastocysts, the inner cell mass and the trophoderm was greatly higher in the NT embryos than in FEs. Moreover, the apoptotic index of the blastocyst from fibroblasts was significantly higher than that of the blastocyst from cumulus cells.


Sujet(s)
Apoptose , Clonage d'organisme , Embryon de mammifère/cytologie , Fécondation in vitro , Techniques de transfert nucléaire , Animaux , Stade de la segmentation de l'oeuf/cytologie , Développement embryonnaire , Femelle , Fibroblastes , Méthode TUNEL , Microscopie confocale , Grossesse , Lapins
9.
Zygote ; 13(1): 73-7, 2005 Feb.
Article de Anglais | MEDLINE | ID: mdl-15984165

RÉSUMÉ

The developmental ability of reconstructed blastocysts from C57BL/6 strain mouse inner cell masses (ICMs) and Kunming strain mouse trophoblasts was assessed. The procedure of ICM replacement was as follows: C57BL/6 ICMs were separated from the blastocysts using immunosurgery. A slit was made in the zona pellucida of a Kunming blastocyst to allow its ICM to extrude. The C57BL/6 ICM was injected into the Kunming blastocoele, and the extruded Kunming ICM was cut off. The reconstructed blastocysts were able to re-expand (77%) and hatch (27.3%) in vitro. A total of 64 reconstructed blastocysts and 124 Kunming blastocysts were co-transferred into the uteri of 11 pseudopregnant Kunming mice, and an ICM replacement offspring was born. The results indicate that reconstructed embryos obtained by inter-strain ICM replacement have the ability to develop to term. This technique may provide a method to solve the pregnancy failure in interspecific cloning.


Sujet(s)
Blastocyste/cytologie , Clonage d'organisme/méthodes , Animaux , Blastocyste/physiologie , Transfert d'embryon , Femelle , Mâle , Souris , Souris de lignée C57BL , Lignées consanguines de souris , Microchirurgie/méthodes , Grossesse , Trophoblastes/cytologie
10.
Mol Reprod Dev ; 71(4): 439-43, 2005 Aug.
Article de Anglais | MEDLINE | ID: mdl-15892042

RÉSUMÉ

Pronucleus transplanted mice have been produced, but their donor male pronuclei were derived from mature sperm and were completely synchronous with female pronuclei because both male and female pronuclei came from the same fertilized oocyte. The present study firstly produced male pronuclei by introducing round spermatids into enucleated mouse oocytes, then transferred the male pronuclei into mouse oocytes at three activation stages and finally compared the effect of three kinds of oocytes on the development of reconstructed embryos. Our results indicate that, in enucleated oocytes, mouse round spermatid nuclei can transform to male pronuclei in a higher proportion, and the synchronization between male and female pronucleus does not significantly influence the early cleavage but the later and full-term development of reconstructed embryos.


Sujet(s)
Embryon de mammifère/physiologie , Foetus/physiologie , Ovule/physiologie , Spermatides/transplantation , Animaux , Femelle , Mâle , Souris
11.
Zygote ; 12(2): 179-84, 2004 May.
Article de Anglais | MEDLINE | ID: mdl-15460114

RÉSUMÉ

Successful production of cloned animals derived from somatic cells has been achieved in sheep, cattle, goats, mice, pigs, rabbits, etc. But the efficiency of nuclear transfer is very low in all species. The present study was conducted to examine somatic nucleus remodelling and developmental ability in vitro of rabbit embryos by transferring somatic cells into enucleated germinal vesicle (GV), metaphase I (MI) or metaphase II (MII) oocytes. Microtubules were organized around condensed chromosomes after the nucleus had been transferred into any of the three types of cytoplasm. A bipolar spindle was formed in enucleated MII cytoplasm. Most of the nuclei failed to form a normal spindle within GV and MI cytoplasm. Some chromosomes scattered throughout the cytoplasm and some formed a monopolar spindle. Pseudopronucleus formation was observed in all three types of cytoplasm. Reconstructed embryos with MI and MII cytoplasm could develop to blastcysts. Nuclei in GV cytoplasm could develop only to the 4-cell stage. These results suggest that (1) GV material is important for nucleus remodelling after nuclear transfer, and (2) oocyte cytoplasm has the capacity to dedifferentiate somatic cells during oocyte maturation.


Sujet(s)
Techniques de transfert nucléaire , Ovocytes/ultrastructure , Animaux , Clonage d'organisme , Femelle , Techniques in vitro , Métaphase , Microtubules/ultrastructure , Ovocytes/cytologie , Ovocytes/croissance et développement , Lapins
12.
Zygote ; 12(1): 75-80, 2004 Feb.
Article de Anglais | MEDLINE | ID: mdl-15214584

RÉSUMÉ

This study assessed the effects of oocyte age, cumulus cells and injection methods on in vitro development of intracytoplasmic sperm injection (ICSI) rabbit embryos. Oocytes were recovered from female rabbits superovulated with PMSG and hCG, and epididymal sperm were collected from a fertile male rabbit. The oocyte was positioned with the first polar body at 12 o'clock position, and a microinjection needle containing a sperm was inserted into the oocyte at 3 o'clock. Oolemma breakage was achieved by aspirating ooplasm, and the aspirated ooplasm and sperm were re-injected into the oocyte. The injected oocytes were cultured in M199 medium containing 10% fetal calf serum at 38 degrees C with 5% CO2 in air. The results showed that oocytes injected at 1 h post-collection produced a higher (p < 0.05) fertilization rate than those injected at 4 or 7 h post-collection. Blastocyst rate in the 1 h group was higher (p < 0.05) than in the 7 h group. Denuded oocytes (group A) and oocytes with cumulus cells (group B) were injected, respectively. Rates of fertilization and development of ICSI embryos were not significantly different (p > 0.05) between the two groups. Four ICSI methods were applied in this experiment. In methods 1 and 2, the needle tip was pushed across half the diameter of the oocyte, and oolemma breakage was achieved by either a single aspiration (method 1) or repeated aspiration and expulsion (method 2) of ooplasm. In methods 3 and 4, the needle tip was pushed to the oocyte periphery opposite the puncture site, and oolemma breakage was achieved by either a single aspiration (method 3) or repeated aspiration and expulsion (method 4) of ooplasm. Fertilization rate in method 2 was significantly higher (p < 0.05) than in methods 1 and 3. Blastocyst rates were not significantly different (p > 0.05) among methods 1, 3 and 4, but method 2 produced a higher (p < 0.05) blastocyst rate than method 3.


Sujet(s)
Ovocytes/cytologie , Injections intracytoplasmiques de spermatozoïdes/méthodes , Animaux , Gonadotrophine chorionique/pharmacologie , Femelle , Gonadotrophine équine/pharmacologie , Humains , Mâle , Modèles animaux , Ovocytes/effets des médicaments et des substances chimiques , Ovocytes/physiologie , Lapins , Spermatozoïdes/physiologie , Superovulation
13.
Zygote ; 12(4): 315-20, 2004 Nov.
Article de Anglais | MEDLINE | ID: mdl-15751540

RÉSUMÉ

Conventional methods of somatic cell nuclear transfer either by electrofusion or direct nucleus injection have very low efficiency in animal cloning, especially interspecies cloning. To increase the efficiency of interspecies somatic cell nuclear transfer, in the present study we introduced a method of whole cell intracytoplasmic injection (WCICI) combined with chemical enucleation into panda-rabbit nuclear transfer and assessed the effects of this method on the enucleation rate of rabbit oocytes and the in vitro development and spindle structures of giant panda-rabbit reconstructed embryos. Our results demonstrated that chemical enucleation can be used in rabbit oocytes and the optimal enucleation result can be obtained. When we compared the rates of cleavage and blastocyst formation of subzonal injection (SUZI) and WCICI using chemically enucleated rabbit oocytes as cytoplasm recipients, the rates in the WCICI group were higher than those in the SUZI group, but there was no statistically siginificant difference (p > 0.05) between the two methods. The microtubule structures of rabbit oocytes enucleated by chemicals and giant panda-rabbit embryos reconstructed by WCICI combined with chemical enucleation were normal. Therefore the present study suggests that WCICI combined with chemical enucleation can provide an efficient and less labor-intensive protocol of interspecies somatic cell nuclear transfer for producing giant panda cloned embryos.


Sujet(s)
Clonage d'organisme/méthodes , Développement embryonnaire/physiologie , Techniques de transfert nucléaire , Ursidae/embryologie , Animaux , A-23187 , Noyau de la cellule/effets des médicaments et des substances chimiques , Cytochalasines , Démécolcine/pharmacologie , Ionomycine , Mâle , Microinjections/méthodes , Microscopie confocale , Microtubules/effets des médicaments et des substances chimiques , Ovocytes/cytologie , Ovocytes/effets des médicaments et des substances chimiques , Lapins , Transplantation hétérologue
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