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1.
Plant Cell ; 34(1): 455-476, 2022 01 20.
Artículo en Inglés | MEDLINE | ID: mdl-34718767

RESUMEN

Stomatal pores and the leaf cuticle regulate evaporation from the plant body and balance the tradeoff between photosynthesis and water loss. MYB16, encoding a transcription factor involved in cutin biosynthesis, is expressed in stomatal lineage ground cells, suggesting a link between cutin biosynthesis and stomatal development. Here, we show that the downregulation of MYB16 in meristemoids is directly mediated by the stomatal master transcription factor SPEECHLESS (SPCH) in Arabidopsis thaliana. The suppression of MYB16 before an asymmetric division is crucial for stomatal patterning, as its overexpression or ectopic expression in meristemoids increased stomatal density and resulted in the formation of stomatal clusters, as well as affecting the outer cell wall structure. Expressing a cutinase gene in plants ectopically expressing MYB16 reduced stomatal clustering, suggesting that cutin affects stomatal signaling or the polarity setup in asymmetrically dividing cells. The clustered stomatal phenotype was rescued by overexpressing EPIDERMAL PATTERNING FACTOR2, suggesting that stomatal signaling was still functional in these plants. Growing seedlings ectopically expressing MYB16 on high-percentage agar plates to modulate tensile strength rescued the polarity and stomatal cluster defects of these seedlings. Therefore, the inhibition of MYB16 expression by SPCH in the early stomatal lineage is required to correctly place the polarity protein needed for stomatal patterning during leaf morphogenesis.


Asunto(s)
Proteínas de Arabidopsis/genética , Arabidopsis/fisiología , División Celular Asimétrica/genética , Polaridad Celular/genética , Regulación de la Expresión Génica de las Plantas/fisiología , Estomas de Plantas/fisiología , Factores de Transcripción/genética , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Factores de Transcripción/metabolismo
2.
J Cell Mol Med ; 27(9): 1250-1260, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36967712

RESUMEN

Oral squamous cell carcinoma (OSCC) has a high recurrence rate and poor prognosis. Hispolon, a polyphenolic compound with antiviral, antioxidant, and anticancer activities, is a potential chemotherapy agent. However, few studies have investigated the anti-cancer mechanism of hispolon in oral cancer. This present study used the cell viability assay, clonogenic assay, fluorescent nuclear staining, and flow cytometry assay to analyse the apoptosis-inducing effects of hispolon in OSCC cells. After hispolon treatment, the apoptotic initiators, cleaved caspase-3, -8, and - 9, were upregulated, whereas the cellular inhibitor of apoptosis protein-1 (cIAP1) was downregulated. Furthermore, a proteome profile analysis using a human apoptosis array revealed the overexpression of heme oxygenase-1 (HO-1) by hispolon, which was determined to be involved in caspase-dependent apoptosis. Moreover, cotreatment with hispolon and mitogen-activated protein kinase (MAPK) inhibitors revealed that hispolon induces apoptosis in OSCC cells through activation of the c-Jun N-terminal kinase (JNK) pathway and not the extracellular signal-regulated kinase (ERK) or p38 pathway. These findings indicate that hispolon may exert an anticancer effect on oral cancer cells by upregulating HO-1 and inducing caspase-dependent apoptosis by activating the JNK pathway.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Humanos , Sistema de Señalización de MAP Quinasas , Hemo-Oxigenasa 1 , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas de Cabeza y Cuello , Neoplasias de la Boca/tratamiento farmacológico , Apoptosis , Proteínas Quinasas JNK Activadas por Mitógenos , Línea Celular Tumoral , Proteínas Quinasas p38 Activadas por Mitógenos
3.
J Intensive Care Med ; 35(12): 1418-1425, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30700200

RESUMEN

Sepsis is a major cause of morbidity and mortality worldwide. With the advance of medical care, the mortality of sepsis has decreased in the past decades. Many treatments and diagnostic tools still lack supporting evidence. We conducted a retrospective population-based cohort study with propensity score matched subcohorts based on a prospectively collected national longitudinal health insurance database in Taiwan. Severe sepsis-associated hospital admissions from 2000 to 2011 based on International Classification of Diseases, Ninth Revision, Clinical Modification codes of infections and acute organ dysfunction were identified. To compare the effectiveness of treatment and diagnostic tool, propensity scores were generated to match the comparable control groups. During the 12-year period, 33 375 patients and 50 465 hospitalizations of severe sepsis were identified. The age-standardized 28-day in-hospital mortality decreased significantly from 21% in 2008 to 15% in 2011 with increasingly implemented treatment and diagnostic tool. After propensity score matching, procalcitonin (odds ratio [OR]: 0.70, 95% confidence interval [95% CI]: 0.61-0.81) and lactate testing (OR: 0.90, 95% CI: 0.84-0.97, respectively), transfusion of packed red blood cell (OR: 0.60, 95% CI: 0.52-0.69), albumin (OR: 0.72, 95% CI: 0.55-0.93), balanced crystalloid (OR: 0.29, 95% CI: 0.20-0.41), and use of dopamine (OR: 0.44, 95% CI: 0.39-0.49) were found to be significantly associated with lower mortality rate. However, inconsistent findings need to be further validated.


Asunto(s)
Sepsis , Estudios de Cohortes , Mortalidad Hospitalaria , Humanos , Estudios Retrospectivos , Sepsis/mortalidad , Sepsis/terapia , Taiwán/epidemiología
4.
Cancer Sci ; 110(6): 1974-1986, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31012976

RESUMEN

We previously found that circulating ß2 -glycoprotein I inhibits human endothelial cell migration, proliferation, and angiogenesis by diverse mechanisms. In the present study, we investigated the antitumor activities of ß2 -glycoprotein I using structure-function analysis and mapped the critical region within the ß2 -glycoprotein I peptide sequence that mediates anticancer effects. We constructed recombinant cDNA and purified different ß2 -glycoprotein I polypeptide domains using a baculovirus expression system. We found that purified ß2 -glycoprotein I, as well as recombinant ß2 -glycoprotein I full-length (D12345), polypeptide domains I-IV (D1234), and polypeptide domain I (D1) significantly inhibited melanoma cell migration, proliferation and invasion. Western blot analyses were used to determine the dysregulated expression of proteins essential for intracellular signaling pathways in B16-F10 treated with ß2 -glycoprotein I and variant recombinant polypeptides. Using a melanoma mouse model, we found that D1 polypeptide showed stronger potency in suppressing tumor growth. Structural analysis showed that fragments A and B within domain I would be the critical regions responsible for antitumor activity. Annexin A2 was identified as the counterpart molecule for ß2 -glycoprotein I by immunofluorescence and coimmunoprecipitation assays. Interaction between specific amino acids of ß2 -glycoprotein I D1 and annexin A2 was later evaluated by the molecular docking approach. Moreover, five amino acid residues were selected from fragments A and B for functional evaluation using site-directed mutagenesis, and P11A, M42A, and I55P mutations were shown to disrupt the anti-melanoma cell migration ability of ß2 -glycoprotein I. This is the first study to show the therapeutic potential of ß2 -glycoprotein I D1 in the treatment of melanoma progression.


Asunto(s)
Movimiento Celular/efectos de los fármacos , Melanoma Experimental/tratamiento farmacológico , Péptidos/farmacología , beta 2 Glicoproteína I/química , Secuencia de Aminoácidos , Animales , Sitios de Unión/genética , Línea Celular Tumoral , Masculino , Melanoma Experimental/genética , Melanoma Experimental/metabolismo , Ratones Endogámicos C57BL , Simulación del Acoplamiento Molecular , Mutagénesis Sitio-Dirigida , Péptidos/química , Péptidos/metabolismo , Dominios Proteicos , Homología de Secuencia de Aminoácido , beta 2 Glicoproteína I/genética , beta 2 Glicoproteína I/metabolismo
5.
Am J Chin Med ; 52(2): 565-581, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38480502

RESUMEN

L48H37 is a synthetic curcumin analog that has anticancer potentials. Here, we further explored the anticancer effect of L48H37 on oral cancer cells and its mechanistic acts. Cell cycle distribution was assessed using flow cytometric analysis. Apoptosis was elucidated by staining with PI/Annexin V and activation of the caspase cascade. Cellular signaling was explored using apoptotic protein profiling, Western blotting, and specific inhibitors. Our findings showed that L48H37 significantly reduced the cell viability of SCC-9 and HSC-3 cells, resulting in sub-G1 phase accumulation and increased apoptotic cells. Apoptotic protein profiling revealed that L48H37 increased cleaved caspase-3, and downregulated cellular inhibitor of apoptosis protein 1 (cIAP1) and X-linked inhibitor of apoptosis protein (XIAP) in SCC-9 cells, and the downregulated cIAP1 and XIAP in both oral cancer cells were also demonstrated by Western blotting. Meanwhile, L48H37 triggered the activation of caspases and mitogen-activated protein kinases (MAPKs). The involvement of c-Jun N-terminal kinase (JNK) and p38 MAPK (p38) in the L48H37-triggered apoptotic cascade in oral cancer cells was also elucidated by specific inhibitors. Collectively, these findings indicate that L48H37 has potent anticancer activity against oral cancer cells, which may be attributed to JNK/p38-mediated caspase activation and the resulting apoptosis. This suggests a potential benefit for L48H37 for the treatment of oral cancer.


Asunto(s)
Curcumina , Neoplasias de la Boca , Humanos , Caspasas/metabolismo , Curcumina/farmacología , Línea Celular Tumoral , Apoptosis , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Caspasa 3/metabolismo , Neoplasias de la Boca/tratamiento farmacológico , Proteínas Inhibidoras de la Apoptosis/farmacología
6.
Pharmaceutics ; 14(6)2022 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-35745828

RESUMEN

Metastatic osteosarcoma often results in poor prognosis despite the application of surgical en bloc excision along with chemotherapy. HO-3867 is a curcumin analog that induces cell apoptosis in several cancers, but the apoptotic effect and its mechanisms on osteosarcoma cells are still unknown. After observing the decrease in cellular viability of three human osteosarcoma U2OS, HOS, and MG-63 cell lines, and the induction of cellular apoptosis and arrest in sub-G1 phase in U2OS and HOS cells by HO-3867, the human apoptosis array showed that heme oxygenase (HO)-1 and cleaved caspase-3 expressions had significant increases after HO-3867 treatment in U2OS cells and vice versa for cellular inhibitors of apoptosis (cIAP)1 and X-chromosome-linked IAP (XIAP). Western blot analysis verified the results and showed that HO-3867 activated the initiators of both extrinsic caspase 8 and intrinsic caspase 9, and significantly increased cleaved PARP expression in U2OS and HOS cells. Moreover, with the addition of HO-3867, ERK1/2, and JNK1/2 phosphorylation were increased in U2OS and HOS cells. Using the inhibitor of JNK (JNK in 8), HO-3867's increases in cleaved caspases 3, 8, and 9 could be expectedly suppressed, indicating that JNK signaling is responsible for both apoptotic pathways, including extrinsic and intrinsic, in U2OS and HOS cells caused by HO-3867. Through JNK signaling, HO-3867 has proven to be effective in causing both extrinsic and intrinsic apoptotic pathways of human osteosarcoma cells.

7.
Plant Environ Interact ; 3(4): 141-154, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37283607

RESUMEN

Stomata are a pivotal adaptation of land plants and control gas exchange. While most plants present solitary stomata, some plant species experiencing chronic water deficiency display clustered stomata on their epidermis; for instance, limestone-grown begonias. Moreover, the membrane receptor TOO MANY MOUTHS (TMM) plays a major role in spacing stomata on the epidermis in Arabidopsis, but the function of its Begonia orthologs is unknown. We used two Asian begonias, Begonia formosana (single stomata) and B. hernandioides (clustered stomata), to explore the physiological function of stomatal clustering. We also introduced the Begonia TMMs into Arabidopsis tmm mutants to study the function of Begonia TMMs. B. hernandioides showed higher water use efficiency under high light intensity, smaller stomata, and faster pore opening than B. formosana. The short distance between stomata in a cluster may facilitate cell-to-cell interactions to achieve synchronicity in stomatal movement. Begonia TMMs function similarly to Arabidopsis TMM to inhibit stomatal formation, although complementation by TMM from the clustered species was only partial. Stomatal clustering in begonias may represent a developmental strategy to build small and closer stomata to achieve fast responses to light which provides tight support between stomatal development and environmental adaption.

8.
Expert Opin Ther Targets ; 26(4): 375-388, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35361044

RESUMEN

BACKGROUND: GO-Y078, a new synthetic analogue of curcumin (CUR), has higher oral bioavailability and anticancer activity than CUR, but the oncostatic effect of GO-Y078 on oral squamous cell carcinoma (OSCC) is largely unknown. RESEARCH DESIGN AND METHODS: In the present study, we examined the oncostatic properties and possible mechanisms of GO-Y078 on human SCC-9 and HSC-3 OSCC cells. RESULTS: Our results indicated that GO-Y078 showed a cytostatic effect against OSCC cells, and this antiproliferative phenomenon stemmed from a mechanism involving multiple levels of cooperation, including cell-cycle G2/M arrest and apoptosis induction. Mechanistically, GO-Y078 treatment induced caspase-mediated apoptosis via upregulating two apoptosis-modulating proteins, SMAC/DIABLO and heme oxygenase (HO)-1. GO-Y078 transcriptionally induced upregulation of the HO-1 gene by increasing the AP-1 DNA-binding activity, which was initiated by activation of the p38 /JNK1/2 pathways. In the clinic, patients with head and neck cancers expressed lower HO-1 and SMAC/DIABLO levels in primary cancer tissues compared to normal tissues. Clinical datasets also revealed that patients with head and neck cancers expressing high HO-1 had afavorable prognosis. CONCLUSIONS: Our results provide new insights into the role of GO-Y078-induced molecular regulation in suppressing OSCC growth and suggest that GO-Y078 has potential therapeutic applications for OSCC.


Asunto(s)
Carcinoma de Células Escamosas , Curcumina , Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Apoptosis , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/patología , Línea Celular Tumoral , Curcumina/análogos & derivados , Curcumina/farmacología , Curcumina/uso terapéutico , ADN/farmacología , ADN/uso terapéutico , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Hemo-Oxigenasa 1/metabolismo , Hemo-Oxigenasa 1/farmacología , Hemo-Oxigenasa 1/uso terapéutico , Humanos , Neoplasias de la Boca/tratamiento farmacológico , Neoplasias de la Boca/metabolismo , Neoplasias de la Boca/patología , Factor de Transcripción AP-1/metabolismo , Factor de Transcripción AP-1/farmacología , Factor de Transcripción AP-1/uso terapéutico , Activación Transcripcional
9.
Pharmaceuticals (Basel) ; 14(6)2021 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-34073773

RESUMEN

Osteosarcoma is the most common primary bone malignancy in teenagers and continues to confer a generally poor prognosis due to its highly metastatic potential. Poor solubility in water and instability of curcumin limits its bioavailability for use in the adjuvant situation to improve the prognosis and the long-term survival of patients with osteosarcoma. To further obtain information regarding the apoptosis induced by a new curcumin analog, GO-Y078, in human osteosarcoma cells, flow cytometric analysis, annexin V-FITC/PI apoptosis staining assay, human apoptosis array, and Western blotting were employed. GO-Y078 dose-dependently decreased viabilities of human osteosarcoma U2OS, MG-63, 143B, and Saos-2 cells and induced sub-G1 fraction arrest and apoptosis in U2OS and 143B cells. In addition to the effector caspase 3 and poly adenosine diphosphate-ribose polymerase, GO-Y078 significantly activated both initiators of extrinsic caspase 8 and intrinsic caspase 9, whereas cellular inhibitors of apoptosis 1 (cIAP-1) and X-chromosome-linked IAP (XIAP) in U2OS and 143B cells were significantly repressed. Moreover, GO-Y078 increased phosphorylation of extracellular signal-regulated protein kinases (ERK)1/2, c-Jun N-terminal kinases (JNK)1/2, and p38 in U2OS and 143B cells. Using inhibitors of JNK (JNK-in-8) and p38 (SB203580), GO-Y078's increases in cleaved caspases 8, 9, and 3 could be expectedly suppressed, but they could not be affected by co-treatment with the ERK inhibitor (U0126). Altogether, GO-Y078 simultaneously induces both apoptotic pathways and cell arrest in U2OS and 143B cells through activating JNK and p38 signaling and repressing IAPs. These findings contribute to a better understanding of the mechanisms responsible for GO-Y078's apoptotic effects on human osteosarcoma cells.

10.
Cancers (Basel) ; 12(8)2020 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-32759757

RESUMEN

Curcumin (CUR) has a range of therapeutic benefits against cancers, but its poor solubility and low bioavailability limit its clinical use. Demethoxycurcumin (DMC) and diphenyl difluoroketone (EF-24) are natural and synthetic curcumin analogues, respectively, with better solubilities and higher anti-carcinogenic activities in various solid tumors than CUR. However, the efficacy of these analogues against non-solid tumors, particularly in acute myeloid leukemia (AML), has not been fully investigated. Herein, we observed that both DMC and EF-24 significantly decrease the proportion of viable AML cells including HL-60, U937, and MV4-11, harboring different NRAS and Fms-like tyrosine kinase 3 (FLT3) statuses, and that EF-24 has a lower half maximal inhibitory concentration (IC50) than DMC. We found that EF-24 treatment induces several features of apoptosis, including an increase in the sub-G1 population, phosphatidylserine (PS) externalization, and significant activation of extrinsic proapoptotic signaling such as caspase-8 and -3 activation. Mechanistically, p38 mitogen-activated protein kinase (MAPK) activation is critical for EF-24-triggered apoptosis via activating protein phosphatase 2A (PP2A) to attenuate extracellular-regulated protein kinase (ERK) activities in HL-60 AML cells. In the clinic, patients with AML expressing high level of PP2A have the most favorable prognoses compared to various solid tumors. Taken together, our results indicate that EF-24 is a potential therapeutic agent for treating AML, especially for cancer types that lose the function of the PP2A tumor suppressor.

11.
Cancers (Basel) ; 12(3)2020 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-32188144

RESUMEN

Demethoxycurcumin (DMC) is a curcumin analogue with better stability and higher aqueous solubility than curcumin after oral ingestion and has the potential to treat diverse cancers, including oral squamous cell carcinoma (OSCC). The aim of this study was to investigate the anticancer effects and underlying mechanisms of DMC against OSCC. We found that DMC suppressed cell proliferation via simultaneously inducing G2/M-phase arrest and cell apoptosis. Mechanistic investigations found that the downregulation of cellular IAP 1 (cIAP1)/X-chromosome-linked IAP (XIAP) and upregulation of heme oxygenase-1 (HO-1) were critical for DMC-induced caspase-8/-9/-3 activation and apoptotic cell death. Moreover, p38 mitogen-activated protein kinase (MAPK) and c-Jun N-terminal kinase (JNK)1/2 were activated by DMC treatment in OSCC cells, and only the inhibition of p38 MAPK significantly abolished DMC-induced HO-1 expression and caspase-8/-9/-3 activation. The analyses of clinical datasets revealed that patients with head and neck cancers expressing high HO-1 and low cIAP1 had the most favorable prognoses. Furthermore, a combinatorial treatment of DMC with epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, gefitinib, significantly enhanced the inhibitory effect of gefitinib on the proliferation of OSCC cells. Overall, the current study supported a role for DCM as part of a therapeutic approach for OSCC through suppressing IAPs and activating the p38-HO-1 axis.

12.
Cancer Res ; 63(21): 7106-12, 2003 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-14612503

RESUMEN

12-O-tetradecanoylphorbolacetate (TPA) influences proliferation, differentiation, and apoptosis in a variety of cells including prostate cancer cells. Here, we show that androgen treatment potentiates TPA-induced apoptosis in androgen-sensitive prostate cancer LNCaP cells but not in androgen-independent prostate cancer cell lines DU145 and PC-3. The use of the antiandrogen bicalutamide (Casodex) rescued LNCaP cells from 5-alpha-dihydrotestosterone (DHT)/TPA-induced apoptosis, suggesting that DHT/TPA-induced apoptosis is mediated by androgen/androgen receptor (AR). In addition, a caspase-3 inhibitor (Ac-DEVD-CHO) reduced the level of apoptosis, suggesting that DHT/TPA-mediated apoptosis occurs through a caspase-3-dependent pathway. A functional reporter assay using nuclear factor (NF) kappaB-luciferase and an electromobility gel shift assay showed that DHT suppressed NFkappaB activity. In addition, apoptosis mediated by combined DHT/TPA treatment was abrogated by overexpression of the NFkappaB subunit p65 in LNCaP-p65 cells, suggesting that NFkappaB may play an important role in regulating the effects of androgen/AR and TPA on apoptosis. Furthermore, use of the c-Jun N-terminal kinase (JNK) inhibitor SB202190 showed that the combination of DHT/TPA increased JNK activation in LNCaP cells but not in LNCaP-p65 cells, demonstrating that NFkappaB may be able to suppress JNK activity. These results indicate that androgen/AR facilitates TPA-induced apoptosis by interruption of the NFkappaB signaling pathway, leading to activation of JNK in LNCaP cells. These data describe a signaling pathway that could potentially be useful in proposed therapeutic treatment strategies exploiting combinations of different agents that control apoptosis in prostate tumors.


Asunto(s)
Apoptosis/efectos de los fármacos , FN-kappa B/antagonistas & inhibidores , Neoplasias Hormono-Dependientes/patología , Neoplasias de la Próstata/patología , Receptores Androgénicos/fisiología , Acetato de Tetradecanoilforbol/farmacología , Andrógenos/fisiología , Apoptosis/fisiología , Caspasa 3 , Caspasas/metabolismo , Línea Celular Tumoral , Dihidrotestosterona/farmacología , Activación Enzimática/efectos de los fármacos , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos , Masculino , Proteínas Quinasas Activadas por Mitógenos/metabolismo , FN-kappa B/biosíntesis , FN-kappa B/genética , FN-kappa B/fisiología , Neoplasias Hormono-Dependientes/tratamiento farmacológico , Neoplasias Hormono-Dependientes/genética , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/genética , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Factor de Transcripción ReIA , Transfección
13.
Fertil Steril ; 79(4): 893-9, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12749426

RESUMEN

OBJECTIVE: To examine the pregnancy potential of frozen-thawed blastocysts that underwent quarter laser-assisted hatching (AH) at the cleaving stage before freezing and to compare clinical and embryo characteristics between the groups that succeeded in and failed to achieve pregnancy. DESIGN: Prospective observational study. PATIENT(S): Thirty-four of 112 patients with frozen blastocysts requiring transfer of thawed embryos between January 2000 and December 2001. SETTING: Assisted reproductive technology unit in a tertiary medical center. INTERVENTION(S): Embryos of patients undergoing blastocyst transfers routinely underwent quarter AH using a nontouch 1.48-microm diode laser. Blastocysts not transferred were cryopreserved using a six-step freezing protocol with glycerol as the cryoprotectant. MAIN OUTCOME MEASURE(S): Postthaw embryo survival and zona pellucida (ZP) maintenance, implantation rate, and clinical pregnancy rate per transfer of thawed blastocysts. RESULT(S): A total of 118 frozen blastocysts was thawed. Of these, 89 (75.4%) embryos survived and were transferred in 35 cycles. Assisted hatching-manipulated ZP tolerated the freeze-thaw procedures without shape distortion in surviving embryos. Eleven (31.4%) clinical pregnancies with 15 intrauterine gestational sacs occurred, for an implantation rate of 16.9%. Those who succeeded in pregnancy tended to have more embryos available before freezing, more original blastocysts of good quality for freezing, and more surviving blastocysts after thawing for transfer than did those who failed to achieve pregnancy. CONCLUSION(S): An acceptable clinical pregnancy rate was obtained from transfer of thawed blastocysts that underwent laser AH on the ZP at the day 3 cleaving embryo stage in fresh cycles in selected patients. Embryo characteristics before freezing played major roles in determining implantation potential of thawed embryos.


Asunto(s)
Blastocisto/fisiología , Criopreservación/métodos , Fertilización In Vitro/métodos , Adulto , Transferencia de Embrión , Desarrollo Embrionario y Fetal/fisiología , Femenino , Humanos , Rayos Láser , Masculino , Inducción de la Ovulación/métodos , Embarazo , Estudios Prospectivos , Zona Pelúcida/fisiología
14.
J Biochem ; 148(3): 349-58, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20587646

RESUMEN

The main protease of the coronavirus causing severe acute respiratory syndrome performs proteolytic processing of the viral polyproteins. The active form of the enzyme is a homodimer with each subunit consisting of three structural domains. Domains I and II, hosting the complete catalytic machinery, constitute the N-terminal chymotrypsin-like folding scaffold and connect to the extra C-terminal domain III by a long loop. Previously, the domain III-truncated enzyme was demonstrated to fold independently into an intact chymotrypsin-like fold, but it showed no enzyme activity. To further delineate the structure-function relationships of the domain III and the long loop, we generated some truncated and mutated M(pro) forms bearing various combinations of the loop with other structural parts of the enzyme. Their conformational and association properties were investigated in detail. Far-ultraviolet circular dichroism (CD) measurements revealed that these fragments could fold independently. The secondary, tertiary and quaternary structures of these mixtures were monitored by CD, fluorescence spectroscopy and analytical ultracentrifugation. However, no enzyme activity was observed for any mutant or mixtures. These observations indicate that the covalent linkage between the chymotrypsin like and the extra domain is essential for enzymatic activity of the main coronavirus protease and for the integrity of its quaternary structure.


Asunto(s)
Cisteína Endopeptidasas/química , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/enzimología , Proteínas Virales/química , Quimotripsina , Proteasas 3C de Coronavirus , Estructura Cuaternaria de Proteína , Estructura Terciaria de Proteína , Subunidades de Proteína
15.
Proc Natl Acad Sci U S A ; 104(31): 12679-84, 2007 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-17652515

RESUMEN

Developmental studies of the prostate have established that ductal morphogenesis, epithelial cytodifferentiation, and proliferation/apoptosis are regulated by androgens acting through stromal androgen receptor (AR). Here, we found mice lacking epithelial AR within the mature prostate (pes-ARKO) developed prostate tissue that was less differentiated and hyperproliferative relative to WT littermates. Epithelial AR protein was significantly decreased in 6-week-old mice and was nearly absent by >/=24 weeks of age. Circulating levels of testosterone, external genitalia, or fertility were not altered in pes-ARKO mice. A significant (P < 0.05) increase in bromo-deoxyuridine-positive epithelia was observed in ventral and dorsal-lateral prostates of pes-ARKO mice at 24 weeks of age. Less differentiation was observed as indicated by decreased epithelial height and glandular infolding through 24 weeks of age, differentiation markers probasin, PSP-94, and Nkx3.1 were sig nificantly decreased, and epithelial sloughing and luminal cell apoptosis increased from 6 to 32 weeks of age in pes-ARKO mice. Gain of function occurred by crossing pes-ARKO to the T857A transgenic mice containing constitutively activated AR. In T857A-pes-ARKO mice prostates were of normal size, contained glandular infoldings, and maintained high secretory epithelium, and the appropriate prostatic epithelial proliferation was restored. Collectively, these results suggest that prostatic epithelial AR plays an important role in the homeostasis of the prostate gland. These data support the hypothesis that epithelial AR controls prostate growth by suppressing epithelial proliferation in the mature gland.


Asunto(s)
Diferenciación Celular , Células Epiteliales/citología , Células Epiteliales/metabolismo , Próstata/citología , Próstata/metabolismo , Receptores Androgénicos/deficiencia , Receptores Androgénicos/metabolismo , Animales , Proliferación Celular , Regulación de la Expresión Génica , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Mutación/genética , Tamaño de los Órganos , Fenotipo , Próstata/crecimiento & desarrollo , Receptores Androgénicos/genética , Treonina/genética , Treonina/metabolismo
16.
Arch Phys Med Rehabil ; 86(1): 146-9, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15641005

RESUMEN

Tocolysis therapy with magnesium sulfate is known to affect calcium homeostasis. Prolonged infusion of magnesium sulfate (MgSO(4)) has been used for the treatment of refractory preterm labor, and has been reported to change maternal calcium homeostasis and possible mineralization. In this case report, we present a woman in her mid thirties who had undergone intravenous MgSO(4) tocolysis therapy, and developed osteoporosis leading to significant morbidity after delivery. The laboratory investigation, including the bone scan, magnetic resonance image, indices of bone turnover, and the results of 2 years of follow-up of bone mineral density, are also reported. This case report supports the existence of a possible association between prolonged intravenous magnesium tocolysis and maternal osteoporosis. To prevent osteoporosis, it is important to avoid a prolonged period of MgSO(4) tocolysis. In cases of prolonged MgSO(4) treatment and bedrest, physicians should be aware of the risk of osteoporosis. The recommended management is also discussed in this report.


Asunto(s)
Sulfato de Magnesio/efectos adversos , Osteoporosis/inducido químicamente , Tocólisis/efectos adversos , Tocolíticos/efectos adversos , Adulto , Densidad Ósea , Esquema de Medicación , Femenino , Humanos , Sulfato de Magnesio/administración & dosificación , Trabajo de Parto Prematuro/tratamiento farmacológico , Embarazo , Tocolíticos/administración & dosificación
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