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1.
Genome Res ; 31(6): 1011-1023, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33858841

RESUMO

Germ cells in Drosophila melanogaster are specified maternally shortly after fertilization and are transcriptionally quiescent until their zygotic genome is activated to sustain further development. To understand the molecular basis of this process, we analyzed the progressing transcriptomes of early male and female germ cells at the single-cell level between germline specification and coalescence with somatic gonadal cells. Our data comprehensively cover zygotic activation in the germline genome, and analyses on genes that exhibit germline-restricted expression reveal that polymerase pausing and differential RNA stability are important mechanisms that establish gene expression differences between the germline and soma. In addition, we observe an immediate bifurcation between the male and female germ cells as zygotic transcription begins. The main difference between the two sexes is an elevation in X Chromosome expression in females relative to males, signifying incomplete dosage compensation, with a few select genes exhibiting even higher expression increases. These indicate that the male program is the default mode in the germline that is driven to female development with a second X Chromosome.


Assuntos
Proteínas de Drosophila , Drosophila , Animais , Mecanismo Genético de Compensação de Dose , Drosophila/genética , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Células Germinativas/metabolismo , Masculino , Diferenciação Sexual
2.
PLoS Genet ; 15(7): e1008062, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31295251

RESUMO

Stem cells rely on instructive cues from their environment. Alterations in microenvironments might contribute to tissue dysfunction and disease pathogenesis. Germline stem cells (GSCs) and cyst stem cells (CySC) in Drosophila testes are normally maintained in the apical area by the testicular hub. In this study, we found that reproduction leads to accumulation of early differentiating daughters of CySCs and GSCs in the testes of aged male flies, due to hyperactivation of Jun-N-terminal kinase (JNK) signaling to maintain self-renewal gene expression in the differentiating cyst cells. JNK activity is normally required to maintain CySCs in the apical niche. A muscle sheath surrounds the Drosophila testis to maintain its long coiled structure. Importantly, reproduction triggers accumulation of the tumor necrosis factor (TNF) Eiger in the testis muscle to activate JNK signaling via the TNF receptor Grindelwald in the cyst cells. Reducing Eiger activity in the testis muscle sheath suppressed reproduction-induced differentiation defects, but had little effect on testis homeostasis of unmated males. Our results reveal that reproduction in males provokes a dramatic shift in the testicular microenvironment, which impairs tissue homeostasis and spermatogenesis in the testes.


Assuntos
Células-Tronco Germinativas Adultas/citologia , Drosophila melanogaster/fisiologia , Reprodução , Células-Tronco Germinativas Adultas/metabolismo , Animais , Diferenciação Celular , Autorrenovação Celular , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/citologia , Feminino , Homeostase , Sistema de Sinalização das MAP Quinases , Masculino , Proteínas de Membrana/metabolismo , Comportamento Sexual Animal , Espermatogênese , Nicho de Células-Tronco , Testículo/citologia , Testículo/metabolismo
3.
Proc Biol Sci ; 284(1855)2017 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-28539513

RESUMO

PHD finger protein 7 (Phf7) is a male germline specific gene in Drosophila melanogaster that can trigger the male germline sexual fate and regulate spermatogenesis, and its human homologue can rescue fecundity defects in male flies lacking this gene. These findings prompted us to investigate conservation of reproductive strategies through studying the evolutionary origin of this gene. We find that Phf7 is present only in select species including mammals and some insects, whereas the closely related G2/M-phase specific E3 ubiquitin protein ligase (G2e3) is in the genome of most metazoans. Interestingly, phylogenetic analyses showed that vertebrate and insect Phf7 genes did not evolve from a common Phf7 ancestor but rather through independent duplication events from an ancestral G2e3 This is an example of parallel evolution in which a male germline factor evolved at least twice from a pre-existing template to develop new regulatory mechanisms of spermatogenesis.


Assuntos
Proteínas de Drosophila/genética , Evolução Molecular , Proteínas de Homeodomínio/genética , Espermatogênese/genética , Animais , Drosophila melanogaster , Duplicação Gênica , Genes de Insetos , Masculino , Mamíferos , Filogenia
4.
Zoolog Sci ; 33(4): 414-25, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27498801

RESUMO

The present study aimed to evaluate the osmoregulatory mechanism of Daisy's medaka, O. woworae,as well as demonstrate the major factors affecting the hypo-osmoregulatory characteristics of euryhaline and stenohaline medaka. The medaka phylogenetic tree indicates that Daisy's medaka belongs to the celebensis species group. The salinity tolerance of Daisy's medaka was assessed. Our findings revealed that 20‰ (hypertonic) saltwater (SW) was lethal to Daisy's medaka. However, 62.5% of individuals survived 10‰ (isotonic) SW with pre-acclimation to 5‰ SW for one week. This transfer regime, "Experimental (Exp.) 10‰ SW", was used in the following experiments. After 10‰ SW-transfer, the plasma osmolality of Daisy's medaka significantly increased. The protein abundance and distribution of branchial Na(+), K(+)-ATPase (NKA) and Na(+), K(+), 2Cl(-) cotransporter 1 (NKCC1) were also examined after transfer to 10‰ SW for one week. Gill NKA activity increased significantly after transfer to 10‰ SW. Meanwhile, elevation of gill NKA αα-subunit protein-abundance was found in the 10‰ SW-acclimated fish. In gill cross-sections, more and larger NKA-immunoreactive (NKA-IR) cells were observed in the Exp. 10‰ SW medaka. The relative abundance of branchial NKCC1 protein increased significantly after transfer to 10‰ SW. NKCC1 was distributed in the basolateral membrane of NKA-IR cells of the Exp. 10‰ SW group. Furthermore, a higher abundance of NKCC1 protein was found in the gill homogenates of the euryhaline medaka, O. dancena, than in that of the stenohaline medaka, O. woworae.


Assuntos
Brânquias/enzimologia , Oryzias/metabolismo , Pressão Osmótica/fisiologia , Simportadores de Cloreto de Sódio-Potássio/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Adaptação Fisiológica/genética , Adaptação Fisiológica/fisiologia , Animais , Regulação Enzimológica da Expressão Gênica , Oryzias/classificação , Filogenia , Salinidade , Simportadores de Cloreto de Sódio-Potássio/genética , ATPase Trocadora de Sódio-Potássio/genética , Especificidade da Espécie , Água/química
5.
Histochem Cell Biol ; 143(1): 69-81, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25163555

RESUMO

The inner opercular membranes of the brackish medaka, Oryzias dancena, have numerous ionocytes, similar to the gill epithelia. By histological observation, this study demonstrated that it is possible to investigate the cellular morphology and function of ionocytes in the opercular membrane. The mitochondria-rich ionocytes in the opercular membranes were traced using rhodamine 123 and a cytochrome c oxidase IV antibody in vital and fixed situations, respectively. To validate different morphologies of seawater (SW)-type and freshwater (FW)-type ionocytes of the opercular membrane of euryhaline brackish medaka, a method of dual observation including immunofluorescence staining and subsequent scanning electron microscopy was used. The apical morphologies of SW- and FW-type ionocytes were hole and flat opening, respectively. In addition, the microvilli were found on the apical surface of the FW-type ionocytes. The SW-type ionocytes exhibited basolateral Na(+), K(+), 2Cl(-) cotransporter and the apical cystic fibrosis transmembrane conductance regulator. In contrast, in the apical region of FW-type ionocytes, Na(+), Cl(-) cotransporter and villin 1-like protein were expressed. In addition, histochemical staining of AgCl precipitation counterstained with a Na(+), K(+)-ATPase α-subunit antibody on the opercular membrane illustrated the role of Cl(-) secretion in the SW-type ionocytes of the brackish medaka. A combination of different observations in this study indicated that the opercular membrane could be a useful surrogate model for histological and functional studies on the epithelial ionocytes of fish gills.


Assuntos
Aclimatação/fisiologia , Água Doce , Brânquias/citologia , Brânquias/metabolismo , Modelos Biológicos , Oryzias/metabolismo , Água do Mar , Animais , Mitocôndrias/metabolismo
6.
Dev Comp Immunol ; 155: 105156, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38423493

RESUMO

Oncorhynchus masou formosanus (Formosa landlocked salmon) is a critically endangered salmonid fish endemic to Taiwan. To begin to understand how its drastic change in lifestyle from anadromous to exclusively river-dwelling is reflected in its immune genes, we characterized the genes encoding six cytokines (IL-2A, IL-2B, IL-4/13A, IL-4/13B1, IL-4/13B2, and IL-17A/F2a) important for T cell responses as no genomic data is available for this fish. Interestingly, all genes appeared homozygous indicative of a genetic bottleneck. The IL2 and IL17A/F2a genes and their products are highly similar to their characterized homologs in Oncorhynchus mykiss (rainbow trout) and other salmonid fish. Two notable differences were observed in IL4/13 family important for type 2 immune responses. First, O. m. formosanus carries not only one but two genes encoding IL-4/13B1 proteins and expansions of these genes are present in other salmonid fish. Second, the OmfoIL4/13A gene carries a 228 bp deletion that results in a premature stop codon and hence a non-functional IL-4/13A cytokine. This suggests a reduced ability for T cell responses against parasitic infections in this species.


Assuntos
Doenças dos Peixes , Oncorhynchus mykiss , Animais , Interleucina-4/genética , Interleucina-4/metabolismo , Citocinas/genética , Citocinas/metabolismo , Genoma
7.
Life Sci Alliance ; 7(10)2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38991729

RESUMO

Embryonic germ cells develop rapidly to establish the foundation for future developmental trajectories, and in this process, they make critical lineage choices including the configuration of their unique identity and a decision on sex. Here, we use single-cell genomics patterns for the entire embryonic germline in Drosophila melanogaster along with the somatic gonadal precursors after embryonic gonad coalescence to investigate molecular mechanisms involved in the setting up and regulation of the germline program. Profiling of the early germline chromatin landscape revealed sex- and stage-specific features. In the male germline immediately after zygotic activation, the chromatin structure underwent a brief remodeling phase during which nucleosome density was lower and deconcentrated from promoter regions. These findings echoed enrichment analysis results of our genomics data in which top candidates were factors with the ability to mediate large-scale chromatin reorganization. Together, they point to the importance of chromatin regulation in the early germline and raise the possibility of a conserved epigenetic reprogramming-like process required for proper initiation of germline development.


Assuntos
Montagem e Desmontagem da Cromatina , Cromatina , Drosophila melanogaster , Desenvolvimento Embrionário , Animais , Masculino , Drosophila melanogaster/embriologia , Drosophila melanogaster/genética , Cromatina/metabolismo , Cromatina/genética , Montagem e Desmontagem da Cromatina/genética , Desenvolvimento Embrionário/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Células Germinativas Embrionárias/metabolismo , Células Germinativas Embrionárias/citologia , Células Germinativas/metabolismo , Epigênese Genética , Feminino , Nucleossomos/metabolismo , Nucleossomos/genética , Análise de Célula Única/métodos
8.
Zhonghua Yi Xue Za Zhi ; 93(3): 165-8, 2013 Jan 15.
Artigo em Zh | MEDLINE | ID: mdl-23570586

RESUMO

OBJECTIVE: To evaluate the efficacy and safety of temozolomide (TMZ) versus semustine (Me-CCNU) in the treatment of recurrent glioblastoma multiforme (GBM) or anaplastic astrocytoma (AA). METHODS: A total of 151 patients with recurrent GBM or AA were enrolled into this randomized, multicentre and open-label study. And 144 patients (intent-to-treat (ITT) population) were assigned randomly into 2 groups. TMZ was given orally at 200 or 150 mg×m(-2)d(-1) (prior chemotherapy) for 5 days, repeated every 28 days. Me-CCNU was given orally at 150 mg×m(-2)×d(-1) once, repeated every 28 days. The treatment periods were within 2 - 6 months and the follow-up period was 6 months. Gadopentetate dimeglumine-magnetic resonance imaging (GD-MRI) or contrast-enhanced computed tomography was performed at 2, 3 and 6 months after treatment to evaluate the image-based progression. Progression-free survival (PFS), overall survival rates at the end of follow-up period and adverse events rates were evaluated. RESULTS: PFS at 6 months was 78.87% in TMZ group and 55.88% in Me-CCNU group (P < 0.05). Overall survival rates at the end of follow-up period were 96.89% in TMZ group and 97.30% in Me-CCNU group (P > 0.05). The objective response rate of TMZ and Me-CCNU groups were complete response (CR) (19.44% vs 6.38%), partial response (PR) (26.39% vs 14.89%), stable disease (SD) (26.39% vs 34.03%) and progressive disease (PD) (27.78% vs 44.68%, P < 0.01). Adverse events rates of TMZ and Me-CCNU were 29.11% and 45.15% respectively (P < 0.05). CONCLUSION: The efficacy of TMZ for patients with recurrent GBM or AA is better than that of Me-CCNU. And TMZ has an acceptable safety profile and its adverse events are mostly mild.


Assuntos
Dacarbazina/análogos & derivados , Glioma/tratamento farmacológico , Semustina , Adulto , Astrocitoma/tratamento farmacológico , Dacarbazina/efeitos adversos , Dacarbazina/uso terapêutico , Feminino , Glioblastoma/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/tratamento farmacológico , Semustina/efeitos adversos , Semustina/uso terapêutico , Temozolomida
9.
PLoS One ; 18(10): e0292137, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37788234

RESUMO

One of the most promising strategies for the management of plastic waste is microbial biodegradation, but efficient degraders for many types of plastics are still lacking, including those for polystyrene (PS). Genomics has emerged as a powerful tool for mining environmental microbes that may have the ability to degrade different types of plastics. In this study, we use 16S rRNA sequencing to analyze the microbiomes for multiple PS samples collected from sites with different vegetation in Taiwan to reveal potential common properties between species that exhibit growth advantages on PS surfaces. Phylum enrichment analysis identified Cyanobacteria and Deinococcus-Thermus as being the most over-represented groups on PS, and both phyla include species known to reside in extreme environments and could encode unique enzymes that grant them properties suitable for colonization on PS surfaces. Investigation of functional enrichment using reference genomes of PS-enriched species highlighted carbon metabolic pathways, especially those related to hydrocarbon degradation. This is corroborated by the finding that genes encoding long-chain alkane hydroxylases such as AlmA are more prevalent in the genomes of PS-associated bacteria. Our analyses illustrate how plastic in the environment support the colonization by different microbes compared to surrounding soil. In addition, our results point to the possibility that alkane hydroxylases could confer growth advantages of microbes on PS.


Assuntos
Plásticos , Poliestirenos , Plásticos/metabolismo , RNA Ribossômico 16S/genética , Bactérias , Biodegradação Ambiental , Oxigenases de Função Mista , Alcanos/metabolismo
10.
Ying Yong Sheng Tai Xue Bao ; 34(4): 1102-1108, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37078330

RESUMO

Given their important roles in the regulation and storage functions for river flow and in the regional ecological environment and ecosystem services, natural lakes are essential for the ecological protection and high-quality development of the Yellow River Basin. We used the Landsat TM/OLI remote sensing data to analyze the area changes of Dongping Lake, Gyaring Lake, and Ngoring Lake, three representative large natural lakes in the Yellow River Basin from 1990 to 2020. We used the landscape ecology approach to study the morphological characteristics of lake shoreline and shoreland changes and the relationship between the landscape indices. The results showed that the main areas of Gyaring Lake and Ngoring Lake were mainly in the trend of expansion, while the main area of Dongping Lake significantly reduced during 1990-2000 and 2010-2020. The changes in the area of lake all occurred mainly near the lake inlet of the river. The shoreline morphology of Dongping Lake was more complex, with the fragmentation and aggregation of shoreland landscape significantly changed. The circularity ratio of Gyaring Lake gradually decreased with the expansion of the lake area, and the number of patches in its shoreland changed significantly. The fractal dimension index-mean of the shoreland of Ngoring Lake was relatively high, the complexity of its shoreline landscape was stronger, and the number of patches had increased significantly from 2000 to 2010. Meanwhile, there was a significant correlation between certain lake shoreline (shoreland) landscape indices. The changes in circularity ratio and shoreline development coefficient caused changes in the patch density of shoreland.


Assuntos
Ecossistema , Rios , Monitoramento Ambiental/métodos , Lagos , China , Conservação dos Recursos Naturais
11.
Hum Vaccin Immunother ; 19(1): 2209001, 2023 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-37249310

RESUMO

As global supply is still inadequate to address the worldwide requirements for HPV vaccines, we assessed the safety and immunogenicity of a new bivalent HPV16/18 vaccine. In this randomized, double-blind, placebo-controlled, phase 2 trial, healthy 9-45-year-old Chinese females in three age cohorts (600 aged 9-17 years; 240 aged 18-26 years; 360 aged 27-45 years) were randomized 1:1 to receive three doses (0,2,6 months) of HPV16/18 vaccine or placebo. We measured neutralizing antibodies against HPV 16 and 18 at 7 months and monitored safety to 12 months in all age cohorts; 9-17-year-old girls were monitored for safety and immunogenicity to 48 months. In vaccinees, 99.8% seroconverted for HPV 16 and 18 types at 7 months; respective GMTs of 5827 (95% CI: 5249, 6468) and 4223 (3785, 4713) were significantly (p < .001) higher than controls for all comparisons. GMTs in the 9-17-year-olds, which were significantly higher than in older women at 7 months, gradually declined to 48 months but remained higher than placebo with seropositivity rates maintained at 98.5% and 97.6% against HPV 16 and 18, respectively. Adverse events occurred at similar rates after vaccine and placebo (69.8% vs. 72.5%, p = .308), including solicited local reactions and systemic adverse events which were mainly mild-to-moderate. The bivalent HPV16/18 vaccine was well tolerated and induced high levels of neutralizing antibodies in all age groups which persisted at high levels to 48 months in the 9-17-year-old age group which would be the target for HPV vaccination campaigns.


Assuntos
Infecções por Papillomavirus , Vacinas contra Papillomavirus , Adolescente , Adulto , Criança , Feminino , Humanos , Pessoa de Meia-Idade , Adulto Jovem , Anticorpos Neutralizantes , Anticorpos Antivirais , Método Duplo-Cego , População do Leste Asiático , Papillomavirus Humano 16 , Papillomavirus Humano 18 , Imunogenicidade da Vacina , Infecções por Papillomavirus/prevenção & controle , Vacinas Combinadas
12.
Hum Vaccin Immunother ; 19(2): 2262635, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37881130

RESUMO

This was a phase 1 dose-escalation study of ZR202-CoV, a recombinant protein vaccine candidate containing a pre-fusion format of the spike (S)-protein (S-trimer) combined with the dual-adjuvant system of Alum/CpG. A total of 230 participants were screened and 72 healthy adults aged 18-59 years were enrolled and randomized to receive two doses at a 28-day interval of three different ZR202-CoV formulations or normal saline. We assessed the safety for 28 days after each vaccination and collected blood samples for immunogenicity evaluation. All formulations of ZR202-CoV were well-tolerated, with no observed solicited adverse events ≥ Grade 3 within 7 days after vaccination. No unsolicited adverse events ≥ Grade 3, or serious adverse events related to vaccination occurred as determined by the investigator. After the first dose, detectable immune responses were observed in all subjects. All subjects that received ZR202-CoV seroconverted at 14 days after the second dose by S-binding IgG antibody, pseudovirus and live-virus based neutralizing antibody assays. S-binding response (GMCs: 2708.7 ~ 4050.0 BAU/mL) and neutralizing activity by pseudovirus (GMCs: 363.1 ~ 627.0 IU/mL) and live virus SARS-CoV-2 (GMT: 101.7 ~ 175.0) peaked at 14 days after the second dose of ZR202-CoV. The magnitudes of immune responses compared favorably with COVID-19 vaccines with reported protective efficacy.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Adulto , Humanos , Adjuvantes Imunológicos , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Método Duplo-Cego , Imunogenicidade da Vacina , SARS-CoV-2 , Vacinas Sintéticas/efeitos adversos , Vacinas Sintéticas/genética , Adolescente , Adulto Jovem , Pessoa de Meia-Idade
13.
J Exp Med ; 203(13): 2919-28, 2006 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-17178919

RESUMO

It is thought that gene conversion (GCV) and somatic hypermutation (SHM) of immunoglobulin (Ig) genes occur in two steps: the generation of uracils in DNA by activation-induced cytidine deaminase, followed by their subsequent repair by various DNA repair pathways to generate sequence-diversified products. It is not known how either of the two steps is targeted specifically to Ig loci. Because of the tight link between transcription and SHM, we have investigated the role of endogenous Ig light chain (IgL) transcriptional control elements in GCV/SHM in the chicken B cell line DT40. Promoter substitution experiments led to identification of a strong RNA polymerase II promoter incapable of supporting efficient GCV/SHM. This surprising finding indicates that high levels of transcription are not sufficient for robust GCV/SHM in Ig loci. Deletion of the IgL enhancer in a context in which high-level transcription was not compromised showed that the enhancer is not necessary for GCV/SHM. Our results indicate that cis-acting elements are important for Ig gene diversification, and we propose that targeting specificity is achieved through the combined action of several Ig locus elements that include the promoter.


Assuntos
Elementos Facilitadores Genéticos/genética , Conversão Gênica/genética , Genes de Cadeia Leve de Imunoglobulina/genética , Regiões Promotoras Genéticas/genética , Hipermutação Somática de Imunoglobulina/genética , Actinas/genética , Animais , Linfócitos B/metabolismo , Bacteriófago T7/genética , Linhagem Celular Tumoral , Citidina Desaminase/genética , Deleção de Genes , Expressão Gênica , Cadeias Pesadas de Imunoglobulinas/genética , Imunoglobulina M/genética , Mutação , Fator 1 de Elongação de Peptídeos/genética , Receptores de Antígenos de Linfócitos B/genética , Transcrição Gênica , Transfecção
14.
Ying Yong Sheng Tai Xue Bao ; 33(9): 2485-2492, 2022 Sep.
Artigo em Zh | MEDLINE | ID: mdl-36131665

RESUMO

Sound ecological environment is an important foundation for promoting high-quality urban development, as it determines the level and quality of urban construction and human settlements. Taking Xi'an as the study area, we used remote sensing ecological index (RSEI) to evaluate the urban ecological environment. The evaluation index system of high-quality urban development was constructed and the entire-array-polygon was used to evaluate the urban development quality. The coupling coordination degree model was used to analyze the temporal variations of the coupling coordination degree of those two factors. The results showed that the urban ecological condition of Xi'an showed a pattern of high in the south and low in the north, and that the level of RSEI had an upward trend in 2010-2020. The RESI of the six inner districts of Xi'an decreased, but the RESI of the surrounding districts of Xi'an was stable or improved. The urban development quality of Xi'an was improved in 2010-2020, though the quality level was still at the low level. The improvement of the three major subsystems of urban development was uneven, and the increase range of three subsystems from largest to smallest was ranked as ecological subsystem > economic subsystem > social subsystem. The coupling coordination of the two kinds of index increased in 2010-2020, and the coordination level had been prompted from barely coordinated to primary.


Assuntos
Reforma Urbana , China , Cidades , Humanos
15.
Ying Yong Sheng Tai Xue Bao ; 33(8): 2057-2067, 2022 Aug.
Artigo em Zh | MEDLINE | ID: mdl-36043811

RESUMO

The Qinling Mountains are an important ecological function area in China. Exploring the trade-offs and synergies of ecosystem services is important for ecological protection and sustainable development in the Qinling Mountains. In this study, we analyzed the spatio-temporal variations of land uses in the Qinling Mountains in 2000, 2010 and 2020 based on remote sensing, meteorological, and soil texture data. The amounts of carbon sequestration, water yield, habitat quality, and soil conservation were calculated with CASA, InVEST and RUSLE models. The relationships between its spatially heterogeneous characteristics and various ecosystem services were analyzed. The results showed that, from 2000 to 2020, the area of arable land and grassland in the study area continued to decrease, the area of forest and building land increased, and the change of water body and unused land was not noticeable. Carbon sequestration was high in the east and low in the west, with an increasing trend. Water production continued to decrease, showing a tendency of higher on the south slope and lower on the north slope. Habitat quality increased steadily, while soil conservation increased and then decreased. Ecosystem services varied across land classes and across ecosystems in the same land class. In general, there was a synergistic relationship between carbon sequestration and soil conservation, habitat quality and soil conservation, carbon sequestration, and habitat quality. There was trade-off between carbon sequestration and water production, soil conservation and water production, habitat quality, and water production. There were significant differences in the relationship between service volumes under different conditions. The results could reduce the risk of trade-offs and maximize overall benefits, and provide a reference for promoting ecologically high-quality development and achieving a win-win situation for natural resource management and human well-being.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , China , Conservação dos Recursos Naturais/métodos , Humanos , Solo , Água
16.
Lancet Microbe ; 3(3): e193-e202, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35098177

RESUMO

BACKGROUND: Safe and effective vaccines are urgently needed to end the COVID-19 pandemic caused by SARS-CoV-2 infection. We aimed to assess the preliminary safety, tolerability, and immunogenicity of an mRNA vaccine ARCoV, which encodes the SARS-CoV-2 spike protein receptor-binding domain (RBD). METHODS: This single centre, double-blind, randomised, placebo-controlled, dose-escalation, phase 1 trial of ARCoV was conducted at Shulan (Hangzhou) hospital in Hangzhou, Zhejiang province, China. Healthy adults aged 18-59 years negative for SARS-CoV-2 infection were enrolled and randomly assigned using block randomisation to receive an intramuscular injection of vaccine or placebo. Vaccine doses were 5 µg, 10 µg, 15 µg, 20 µg, and 25 µg. The first six participants in each block were sentinels and along with the remaining 18 participants, were randomly assigned to groups (5:1). In block 1 sentinels were given the lowest vaccine dose and after a 4-day observation with confirmed safety analyses, the remaining 18 participants in the same dose group proceeded and sentinels in block 2 were given their first administration on a two-dose schedule, 28 days apart. All participants, investigators, and staff doing laboratory analyses were masked to treatment allocation. Humoral responses were assessed by measuring anti-SARS-CoV-2 RBD IgG using a standardised ELISA and neutralising antibodies using pseudovirus-based and live SARS-CoV-2 neutralisation assays. SARS-CoV-2 RBD-specific T-cell responses, including IFN-γ and IL-2 production, were assessed using an enzyme-linked immunospot (ELISpot) assay. The primary outcome for safety was incidence of adverse events or adverse reactions within 60 min, and at days 7, 14, and 28 after each vaccine dose. The secondary safety outcome was abnormal changes detected by laboratory tests at days 1, 4, 7, and 28 after each vaccine dose. For immunogenicity, the secondary outcome was humoral immune responses: titres of neutralising antibodies to live SARS-CoV-2, neutralising antibodies to pseudovirus, and RBD-specific IgG at baseline and 28 days after first vaccination and at days 7, 15, and 28 after second vaccination. The exploratory outcome was SARS-CoV-2-specific T-cell responses at 7 days after the first vaccination and at days 7 and 15 after the second vaccination. This trial is registered with www.chictr.org.cn (ChiCTR2000039212). FINDINGS: Between Oct 30 and Dec 2, 2020, 230 individuals were screened and 120 eligible participants were randomly assigned to receive five-dose levels of ARCoV or a placebo (20 per group). All participants received the first vaccination and 118 received the second dose. No serious adverse events were reported within 56 days after vaccination and the majority of adverse events were mild or moderate. Fever was the most common systemic adverse reaction (one [5%] of 20 in the 5 µg group, 13 [65%] of 20 in the 10 µg group, 17 [85%] of 20 in the 15 µg group, 19 [95%] of 20 in the 20 µg group, 16 [100%] of 16 in the 25 µg group; p<0·0001). The incidence of grade 3 systemic adverse events were none (0%) of 20 in the 5 µg group, three (15%) of 20 in the 10 µg group, six (30%) of 20 in the 15 µg group, seven (35%) of 20 in the 20 µg group, five (31%) of 16 in the 25 µg group, and none (0%) of 20 in the placebo group (p=0·0013). As expected, the majority of fever resolved in the first 2 days after vaccination for all groups. The incidence of solicited systemic adverse events was similar after administration of ARCoV as a first or second vaccination. Humoral immune responses including anti-RBD IgG and neutralising antibodies increased significantly 7 days after the second dose and peaked between 14 and 28 days thereafter. Specific T-cell response peaked between 7 and 14 days after full vaccination. 15 µg induced the highest titre of neutralising antibodies, which was about twofold more than the antibody titre of convalescent patients with COVID-19. INTERPRETATION: ARCoV was safe and well tolerated at all five doses. The acceptable safety profile, together with the induction of strong humoral and cellular immune responses, support further clinical testing of ARCoV at a large scale. FUNDING: National Key Research and Development Project of China, Academy of Medical Sciences China, National Natural Science Foundation China, and Chinese Academy of Medical Sciences.


Assuntos
COVID-19 , SARS-CoV-2 , Adulto , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , China , Humanos , Imunogenicidade da Vacina , Imunoglobulina G , Pandemias/prevenção & controle , Glicoproteína da Espícula de Coronavírus , Vacinas Sintéticas , Vacinas de mRNA
17.
Sci Rep ; 11(1): 6308, 2021 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-33737548

RESUMO

Germ cells in Drosophila melanogaster need intrinsic factors along with somatic signals to activate proper sexual programs. A key factor for male germline sex determination is PHD finger protein 7 (Phf7), a histone reader expressed in the male germline that can trigger sex reversal in female germ cells and is also important for efficient spermatogenesis. Here we find that the evolutionarily novel C-terminus in Phf7 is necessary to turn on the complete male program in the early germline of D. melanogaster, suggesting that this domain may have been uniquely acquired to regulate sexual differentiation. We further looked for genes regulated by Phf7 related to sex determination in the embryonic germline by transcriptome profiling of FACS-purified embryonic gonads. One of the genes positively-regulated by Phf7 in the embryonic germline was an HP1family member, Heterochromatin Protein 1D3 chromoshadow domain (HP1D3csd). We find that this gene is needed for Phf7 to induce male-like development in the female germline, indicating that HP1D3csd is an important factor acting downstream of Phf7 to regulate germline masculinization.


Assuntos
Proteínas Cromossômicas não Histona/genética , Proteínas de Drosophila/genética , Proteínas de Homeodomínio/genética , Processos de Determinação Sexual/genética , Diferenciação Sexual/genética , Animais , Drosophila melanogaster/genética , Drosophila melanogaster/crescimento & desenvolvimento , Desenvolvimento Embrionário/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento/genética , Células Germinativas/crescimento & desenvolvimento , Gônadas/crescimento & desenvolvimento , Masculino , Transcriptoma/genética
18.
Fertil Steril ; 114(1): 133-143, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32553473

RESUMO

OBJECTIVE: To identify the genetic etiology of recurrent disorders of sex development (DSDs) in a Taiwanese family with 46,XY sex reversal and hypospadias. DESIGN: Genetic and functional studies. SETTING: Academic hospital. PATIENT(S): A three-generation family consisting of 22 members, with eight cases of 46,XY DSD, of whom four have 46,XY male-to-female sex reversal and four are 46,XY males with hypospadias. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Results of exome sequencing and in vitro protein and RNA analyses. RESULT(S): All patients with DSDs were found to carry heterozygous missense mutations in the doublesex and mab-3-related transcription factor 3 (DMRT3; rs187176004, c.A815C, p.K272T) and 2',5'-oligoadenylate synthetase 3 (OAS3; rs16942374, c.G2606A, p.R869H) genes. The DMRT3 mutation increased estrogen receptor 1 (ESR1) expression. Upon binding with the OAS3-RNase L complex, wild-type DMRT3 promoted degradation of ESR1 mRNA. However, the DMRT3A815C-OAS3G2606A complex interacted less strongly with ESR1 mRNA and RNase L, ultimately preventing ESR1 mRNA degradation. The interactions between DMRT3, OAS3, and RNase L were confirmed in the patients' testis. CONCLUSION(S): Our results indicate that DMRT3 and OAS3 are involved in human DSDs by controlling ESR1 expression.


Assuntos
2',5'-Oligoadenilato Sintetase/genética , Receptor alfa de Estrogênio/genética , Disgenesia Gonadal 46 XY/genética , Hipospadia/genética , Mutação de Sentido Incorreto , Diferenciação Sexual/genética , Fatores de Transcrição TFII/genética , Fatores de Transcrição/genética , Endorribonucleases/genética , Endorribonucleases/metabolismo , Receptor alfa de Estrogênio/metabolismo , Feminino , Regulação da Expressão Gênica , Predisposição Genética para Doença , Disgenesia Gonadal 46 XY/diagnóstico , Disgenesia Gonadal 46 XY/fisiopatologia , Células HEK293 , Hereditariedade , Humanos , Hipospadia/diagnóstico , Hipospadia/fisiopatologia , Masculino , Linhagem , Fenótipo , Taiwan , Sequenciamento do Exoma
19.
Adv Immunol ; 94: 109-25, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17560273

RESUMO

After their assembly by V(D)J recombination, immunoglobulin (Ig) genes undergo somatic hypermutation, gene conversion, and class switch recombination to generate additional antibody diversity. The three diversification processes depend on activation-induced cytidine deaminase (AID) and are tightly linked to transcription. The reactions occur primarily on Ig genes and the molecular mechanisms that underlie their targeting to Ig loci have been of intense interest. In this chapter, we discuss the evidence linking transcription and transcriptional control elements to the three diversification pathways, and we consider how various features of chromatin could render parts of the genome permissive for AID-mediated sequence diversification.


Assuntos
Diversidade de Anticorpos/genética , Citidina Desaminase , Switching de Imunoglobulina/genética , Hipermutação Somática de Imunoglobulina/genética , Animais , Humanos
20.
Zhonghua Yi Xue Za Zhi ; 89(29): 2059-62, 2009 Aug 04.
Artigo em Zh | MEDLINE | ID: mdl-20017331

RESUMO

OBJECTIVE: To investigate the efficacy and safety of temozolomide (TMZ) and lomustine (CCNU) in malignant brain gliomas. METHODS: In this multicenter, randomized, double-blind, positive-controlled study, patients with malignant glioma of a histological grade III/IV were randomly divided into two groups. In experiment group, TMZ capsule 150 mg/m2 was given orally on days 1 through 5 and CCNU placebo 130 mg/m2 while on day 1. In control group, CCNU capsule 130 mg/m2 was taken orally on day 1 and TMZ placebo 150 mg/m2 while on days 1 through 5. In both groups drugs were given on the first 5 days of 28 day therapeutic course. Every patient was administered at least 3 cycles continuously. RESULTS: 97 patients were enrolled in the clinical trial, 86 cases of which were evaluable for efficacy. The basic conditions of patients in both groups were comparable. After 12 weeks, the response rates in TMZ and CCNU group were 35.71% and 9.09% (P < 0.01) respectively, and the clinical benefit rates in TMZ and CCNU group were 90.48% and 75.00% (P < 0.05) respectively. No obvious improvement was showed in quality of life and neural symptoms in both groups. The common side effects of TMZ were nausea and vomiting with grade I/II. CONCLUSION: TMZ capsule can produce higher efficacy than CCNU in the treatment for refractory malignant brain glioma patients with an acceptable safety profile , indicating that TMZ could be an ideal chemotherapy selection for malignant brain glioma.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Dacarbazina/análogos & derivados , Glioma/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Dacarbazina/uso terapêutico , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Temozolomida , Adulto Jovem
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