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1.
Protist ; 173(3): 125881, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35567937

RESUMO

A new bakuellid ciliate, Holostichides eastensis nov. spec. isolated from China, is investigated in terms of its morphology, ontogenesis, and molecular phylogenesis. It is characterized by size 150-180 µm × 45-60 µm in vivo; 27-46 macronuclear nodules; cortical granules dark brown, spherical, about 0.5 µm across, clustered in groups and then arranged longitudinally; three frontal cirri with one to four smaller cirri below the middle one, a buccal cirrus, nine to 15 frontoterminal cirri, and midventral complex composed of five to eight cirral pairs and two long midventral rows. The main events during binary fission are as follows: (1) in the proter, the undulating membrane anlage is formed from both the dedifferentiation of old undulating membranes and the basal bodies developing de novo, and the proximal part of the parental adoral zone of membranelles is renewed by a field of basal bodies that originates de novo; (2) in the opisthe, the oral primordium is formed intrakinetally; (3) besides the middle frontal cirrus and buccal cirrus, the FVT-anlagen II produces the extra one to four cirri. Phylogenetic analyses based on SSU rDNA sequence data suggest a close relationship between Holostichides eastensis nov. spec. and its congeners, indicating that the genus Holostichides is monophyletic.


Assuntos
Cilióforos , Hypotrichida , Cilióforos/genética , Hypotrichida/genética , Morfogênese , Filogenia , Solo
2.
Eur J Protistol ; 84: 125879, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35358743

RESUMO

The morphogenesis of two hypotrich ciliates, Notohymena antarctica Foissner, 1996 and Engelmanniella mobilis (Engelmann, 1862) Foissner, 1982, were investigated using protargol staining. The main events of the oxytrichid Notohymena antarctica during binary fission are as follows: (1) the oral primordium of the opisthe is formed apokinetally left of transverse cirrus II/1; (2) six streaks of frontal-ventral-transverse cirral anlagen are segmented in the ordinary pattern 1: 3: 3: 3: 4: 4 from left to right, which form three frontal, four frontoventral, one buccal, three ventral, two pretransverse ventral and five transverse cirri; (3) marginal anlagen are formed intrakinetally and the right marginal anlagen develop much earlier than those on the left. Phylogenetic analyses based on SSU rDNA sequence data indicate that Notohymena is monophyletic. A remarkable morphogenetic feature in E. mobilis is the mode of formation of the right marginal rows. In this paper, we clarified that the right marginal anlagen of E. mobilis are formed and develop to the right of the parental outer right marginal row, and that the grandparental (inner) right marginal row and great-grand parental (the outermost) left marginal row are resorbed. It is the first time to report a population of E. mobilis with comprehensive information, i.e. the morphology, ontogeny and molecular sequence.


Assuntos
Cilióforos , Hypotrichida , Regiões Antárticas , Divisão Celular , China , Filogenia
3.
Cell Mol Immunol ; 19(4): 504-515, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34983946

RESUMO

Sepsis is a heterogeneous syndrome induced by a dysregulated host response to infection. Glycolysis plays a role in maintaining the immune function of macrophages, which is crucial for severely septic patients. However, how the pathways that link glycolysis and macrophages are regulated is still largely unknown. Here, we provide evidence to support the function of KLF14, a novel Krüppel-like transcription factor, in the regulation of glycolysis and the immune function of macrophages during sepsis. KLF14 deletion led to significantly increased mortality in lethal models of murine endotoxemia and sepsis. Mechanistically, KLF14 decreased glycolysis and the secretion of inflammatory cytokines by macrophages by inhibiting the transcription of HK2. In addition, we confirmed that the expression of KLF14 was upregulated in septic patients. Furthermore, pharmacological activation of KLF14 conferred protection against sepsis in mice. These findings uncover a key role of KLF14 in modulating the inflammatory signaling pathway and shed light on the development of KLF14-targeted therapeutics for sepsis.


Assuntos
Sepse , Fatores de Transcrição , Animais , Glicólise , Hexoquinase , Humanos , Imunidade , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fatores de Transcrição/metabolismo
4.
Sci Total Environ ; 812: 151460, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34762958

RESUMO

Ensuring access to water is one of the United Nations' Sustainable Development Goals. Water demand management, which has emerged as an important approach to secure water supply, should be underpinned by a good understanding of how the public perceive their use of water. In this study, we investigated public perceptions of physical and virtual water in China through online surveys using the multi-level regression models (two-level models). Based on 3262 responses, we found that overall, participants underestimated water uses and differences between water uses (daily potable water of an adult, shower, toilet flushing, etc.). Most participants did not possess the knowledge of virtual water embedded in their daily consumed products. Individuals showed rather different perceptions in water use, which were affected by gender, age, education, resource and environmental attitude, water saving behaviors, water price and residential water source. In combination with previous findings in the United States, we concluded that despite different natural water endowment and socio-economic and cultural conditions, underestimation of water use is commonly shared by Chinese and Americans. This highlights a need of strengthening public knowledge of water use. The results are useful in informing policies to enhance the public's awareness of water use towards improved water demand management.


Assuntos
Opinião Pública , Água , Adulto , China , Humanos , Inquéritos e Questionários , Estados Unidos , Abastecimento de Água
5.
Front Microbiol ; 12: 777540, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34917056

RESUMO

The morphology and morphogenesis of Pseudosincirra longicirrata nov. gen. and nov. comb., isolated from southern China, were investigated with living observation and protargol staining. Our population is similar to the original population in living characteristics and ciliary patterns. The main determinable morphogenetic features of P. longicirrata nov. comb. are the presence of five frontoventral-transverse cirral anlagen (FVT-anlagen) and a dorsomarginal kinety anlage. According to the origin of FVT-anlagen IV and V in proter, it can be determined that P. longicirrata nov. comb. possesses two frontoventral rows and one right marginal row. Hence, a new genus, Pseudosincirra nov. gen., is proposed, and the diagnosis of P. longicirrata nov. comb. is improved. The new genus is diagnosed as follows: adoral zone of membranelles and undulating membranes is in a Gonostomum pattern; there are three enlarged frontal cirri, one buccal cirrus, and one parabuccal cirrus; postperistomial cirrus and transverse cirri are lacking; there are two more or less long frontoventral rows and one right and two or more left marginal rows; cirri within all rows very widely spaced; dorsal kinety pattern is of Urosomoida type, that is, three dorsal kineties and one dorsomarginal kinety; and caudal cirri are present. Phylogenetic analyses based on the small subunit ribosomal (SSU rDNA) sequence data indicate that P. longicirrata nov. comb. clusters with Deviata and Perisincirra. It is considered that Pseudosincirra nov. gen. and Perisincirra paucicirrata should be assigned to the family Deviatidae; fine cirri, and cirri within all rows being relatively widely spaced, should be considered as plesiomorphies of Deviatidae; and Deviatidae is closely related to Dorsomarginalia or Strongylidium-Hemiamphisiella-Pseudouroleptus.

6.
Eur J Protistol ; 81: 125795, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34717076

RESUMO

The morphology, morphogenesis, and molecular phylogeny of Bakuella (Pseudobakuella) guangdongica n. sp., isolated from southern China, were investigated. The new species is characterized by a body length of 150-225 µm in vivo; 35-42 adoral membranelles; 3-5 buccal, two frontoterminal, 7-12 transverse and two pretransverse ventral cirri; midventral complex comprised of 10-20 pairs and two rows extending to transverse cirri; posterior part of marginal rows slightly overlapping; colorless cortical granules about 1 µm across, arranged in small groups; soil habitat. Its main ontogenetic features are: (1) in the proter, the parental adoral zone of membranelles is completely renewed by new structures; (2) in the opisthe, the oral primordium originates apokinetally, some old midventral cirri join the formation of frontoventral-transverse cirral anlagen; (3) the anlagen for marginal rows and dorsal kineties develop intrakinetally; and (4) the numerous macronuclear nodules fuse into a single mass before dividing. Phylogenetic analyses based on the SSU rDNA sequence suggest the non-monophyly of the genus Bakuella.


Assuntos
Cilióforos , Hypotrichida , China , Cilióforos/genética , DNA Ribossômico , Hypotrichida/genética , Filogenia
7.
Mol Carcinog ; 60(8): 538-555, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34062009

RESUMO

Triple-negative breast cancer (TNBC) is the most malignant subtype of breast cancer. Some microRNAs (miRNAs) were abnormally expressed in TNBC, and they are closely related to the occurrence and progression of TNBC. Here, we found that miR-506 was significantly downregulated in TNBC and relatively lower miR-506 expression predicted a poorer prognosis. Moreover, we found that miR-506 could inhibit MDA-MB-231 cell viability, colony formation, migration, and invasion, and suppress the ERK/Fos oncogenic signaling pathway through upregulating its direct target protein proenkephalin (PENK). Therefore, miR-506 was proposed as a nucleic acid drug for TNBC therapy. However, miRNA is unstable in vivo, which limiting its application as a therapeutic drug via conventional oral or injected therapies. Here, a gelatin nanosphere (GN) delivery system was applied for the first time to load exogenous miRNA. Exogenous miR-506 mimic was loaded on GNs and injected into the in situ TNBC animal model, and the miR-506 could achieve sustained and controlled release. The results confirmed that overexpression of miR-506 and PENK in vivo through loading on GNs inhibited in situ triple-negative breast tumor growth and metastasis significantly in the xenograft model. Moreover, we indicated that the ERK/Fos signaling pathway was intensively inactivated after overexpression of miR-506 and PENK both in vitro and in vivo, which was further validated by the ERK1/2-specific inhibitor SCH772984. In conclusion, this study demonstrates that miR-506-loaded GNs have great potential in anti-TNBC aggressiveness therapy.


Assuntos
Encefalinas/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Precursores de Proteínas/genética , Proteínas Proto-Oncogênicas c-fos/metabolismo , Transdução de Sinais , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/metabolismo , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Progressão da Doença , Feminino , Gelatina , Técnicas de Transferência de Genes , Humanos , Camundongos , MicroRNAs/administração & dosagem , Nanosferas , Neoplasias de Mama Triplo Negativas/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Eur J Protistol ; 78: 125766, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33548733

RESUMO

The morphology, morphogenesis and molecular phylogeny of a new saline soil hypotrich ciliate, Uroleptoides salina nov. spec., discovered from China, was investigated. The new species is characterized as follows: body 150-215 × 40-50 µm in vivo, slender and highly flexible; usually four ellipsoidal macronuclear nodules; contractile vacuole absent; cortical granules absent; endosymbiotic algae present; amphisiellid median cirral row consists of 14-25 cirri and terminates about 47% down length of body; usually three buccal cirri and 3-13 cirri left of anterior portion of amphisiellid median cirral row; 3-5 transverse cirri. Morphogenesis during binary fission is characterized by: (1) the parental adoral zone of membranelles is retained completely, parental paroral contributes to the formation of the undulating membranes anlage for the proter; (2) the oral primordium of the opisthe is formed apokinetally; and (3) the amphisiellid median cirral row is formed from two anlagen. Phylogenetic analyses based on SSU rDNA sequence data show that Uroleptoides salina nov. spec. has a close relationship with its morphologically similar species, U. longiseries, U. magnigranulosus, Orthamphisiella breviseries, and Parabistichella variabilis.


Assuntos
Hypotrichida/classificação , Filogenia , Solo/parasitologia , Hypotrichida/citologia , Hypotrichida/genética , RNA Ribossômico 18S/genética , Especificidade da Espécie
9.
Front Microbiol ; 12: 774226, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35222294

RESUMO

Because the original description of Bakuella (Bakuella) marina, type of the genus, is only based on protargol-impregnated specimens, one of the important living features, namely, the presence/absence of cortical granules, remains unknown so far. In the present work, a detailed investigation of a Chinese population of B. (Bakuella) marina is carried out using the integrated approaches, and the live morphology, ontogenesis, and molecular information of B. (Bakuella) marina are presented for the first time. The infraciliature of this population corresponds perfectly with that of the original description. The in vivo observation indicates that B. (Bakuella) marina possesses colorless cortical granules. The most prominent morphogenetic feature of B. (Bakuella) marina is that the parental adoral zone of membranelles is completely replaced by the newly formed one of the proters. Molecular phylogenetic analysis based on a small subunit ribosomal gene (SSU rDNA) shows that five Bakuella species are clustered with the species from other six Urostylid genera, namely, Anteholosticha, Apobakuella, Diaxonella, Holosticha, Neobakuella, and Urostyla. The monophyletic probabilities of the family Bakuellidae, genus Bakuella, subgenus B. (Bakuella), and subgenus B. (Pseudobakuella) are rejected by the approximately unbiased test. This study further shows that the family Bakuellidae, genus Bakuella, and subgenus B. (Bakuella) are all nonmonophyletic groups. In order to establish a reasonable classification system, information on molecular and morphogenesis of more Bakuellids and its related species is urgently needed.

10.
J Eukaryot Microbiol ; 68(1): e12832, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33141463

RESUMO

The morphology, morphogenesis and molecular phylogeny of Parabistichella dieckmanni (Foissner, 1998) Foissner, 2016, isolated from north China, were investigated. The Chinese population was characterized as having five to seven frontal cirri in corona, four to seven buccal cirri arranged in a row, two to four short frontal rows and two long frontoventral rows, three to seven transverse cirri, four macronuclear nodules, three dorsal kineties following a Gonostomum-pattern, and caudal cirri absent. Morphogenetic research reveals that the main characteristics during binary fission are as follows: (1) the long left frontoventral row is formed by two or three anlagen; (2) the posterior part of the parental adoral zone of membranelles is renewed, and the oral primordium of the opisthe is formed intrakinetally; (3) FVT-anlagen I to VI (or V, VII) produce each a frontal cirrus to form the frontal corona; (4) development of dorsal kineties follows the Gonostomum-pattern. Phylogenetic analyses showed that P. dieckmanni does not group with other Parabistichella species. Therefore, the genus Parabistichella is polyphyletic. Additionally, Parabistichella variabilis n. comb. (basionym: Bistichella variabilis He & Xu, 2011) and Parabistichella cheni n. nom. (basionym: Parabistichella variabilis Jiang et al., 2013) were suggested.


Assuntos
Hypotrichida/citologia , Hypotrichida/crescimento & desenvolvimento , China , DNA de Protozoário/análise , DNA Ribossômico/análise , Hypotrichida/classificação , Morfogênese , Filogenia , Solo/parasitologia
11.
Eur J Protistol ; 77: 125748, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33279756

RESUMO

A soil hypotrich ciliate, Afrokahliella paramacrostoma n. sp., was discovered in China. Its morphology, morphogenesis and molecular phylogeny were investigated using standard methods. The new species is characterized as follows: body about 140-180 × 60-70 µm in vivo, cortical granules absent, contractile vacuole positioned about 40% down length of body, 5-9 macronuclear nodules, 34-49 adoral membranelles, 3-5 buccal and 3-6 parabuccal cirri, usually two frontoventral rows, three or four left and two or three right marginal rows, three dorsal kineties and one dorsomarginal kinety; 1-3 and one or two caudal cirri located at the ends of dorsal kineties 1 and 2, respectively. The ontogenetic process is characterized by: (1) the marginal anlagen on each side develop in the outer right and the inner left marginal rows, respectively; (2) five frontoventral-transverse cirral anlagen, anlagen II-IV develop in secondary mode; (3) dorsal morphogenesis follows a typical Urosomoida-pattern, no parental dorsal kineties are retained; (4) caudal cirri are generated at the ends of dorsal kineties 1 and 2. Phylogenetic analyses based on SSU rDNA sequence data reveals that Afrokahliella paramacrostoma n. sp. is closely related to Parakahliella macrostoma and Hemiurosomoida longa.


Assuntos
Hypotrichida/classificação , Filogenia , Solo/parasitologia , China , DNA de Protozoário/genética , Hypotrichida/citologia , Hypotrichida/genética , RNA Ribossômico 18S/genética , Especificidade da Espécie
12.
Mol Metab ; 42: 101098, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33045434

RESUMO

OBJECTIVE: Aging and chronic glucocorticoid excess share a number of critical features, including the development of central obesity, insulin resistance and osteoporosis. Previous studies have shown that skeletal glucocorticoid signalling increases with aging and that osteoblasts mediate the detrimental skeletal and metabolic effects of chronic glucocorticoid excess. Here, we investigated whether endogenous glucocorticoid action in the skeleton contributes to metabolic dysfunction during normal aging. METHODS: Mice lacking glucocorticoid signalling in osteoblasts and osteocytes (HSD2OB/OCY-tg mice) and their wild-type littermates were studied until 3, 6, 12 and 18 months of age. Body composition, adipose tissue morphology, skeletal gene expression and glucose/insulin tolerance were assessed at each timepoint. Leptin sensitivity was assessed by arcuate nucleus STAT3 phosphorylation and inhibition of feeding following leptin administration. Tissue-specific glucose uptake and adipose tissue oxygen consumption rate were also measured. RESULTS: As they aged, wild-type mice became obese and insulin-resistant. In contrast, HSD2OB/OCY-tg mice remained lean and insulin-sensitive during aging. Obesity in wild-type mice was due to leptin resistance, evidenced by an impaired ability of exogenous leptin to suppress food intake and phosphorylate hypothalamic STAT3, from 6 months of age onwards. In contrast, HSD2OB/OCY-tg mice remained leptin-sensitive throughout the study. Compared to HSD2OB/OCY-tg mice, leptin-resistant wild-type mice displayed attenuated sympathetic outflow, with reduced tyrosine hydroxylase expression in both the hypothalamus and thermogenic adipose tissues. Adipose tissue oxygen consumption rate declined progressively in aging wild-type mice but was maintained in HSD2OB/OCY-tg mice. At 18 months of age, adipose tissue glucose uptake was increased 3.7-fold in HSD2OB/OCY-tg mice, compared to wild-type mice. CONCLUSIONS: Skeletal glucocorticoid signalling is critical for the development of leptin resistance, obesity and insulin resistance during aging. These findings underscore the skeleton's importance in the regulation of body weight and implicate osteoblastic/osteocytic glucocorticoid signalling in the aetiology of aging-related obesity and metabolic disease.


Assuntos
Envelhecimento/metabolismo , Glucocorticoides/metabolismo , Leptina/metabolismo , Tecido Adiposo/metabolismo , Fatores Etários , Animais , Núcleo Arqueado do Hipotálamo/metabolismo , Composição Corporal , Peso Corporal/fisiologia , Osso e Ossos/metabolismo , Encéfalo/metabolismo , Feminino , Glucose/metabolismo , Hipotálamo/metabolismo , Insulina/metabolismo , Resistência à Insulina/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Camundongos Transgênicos , Obesidade/metabolismo , Obesidade/fisiopatologia , Transdução de Sinais/efeitos dos fármacos , Termogênese
13.
Plant Signal Behav ; 15(12): 1816644, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32897833

RESUMO

Orchid mycorrhizal fungi (OMF) are essential for orchids growth. Bletilla striata (Thunb.) Rchb.f.(Orchidaceae) has high ornamental and medicinal value. Beneficial OMF isolation is crucial to improve the survival rate of B. striata tissue culture and transplanting. In this study, we isolated and identified the beneficial OMF in B. striata from the roots of sterilized wild B. striata seedlings by culturing in four different mediums. The germination states of B. striata seeds inoculated with diverse OMF were classified and calculated. Fresh and dry weight increments of B. striata seedlings inoculated with diverse OMF were recorded after 90 d of culturing on 1/2 MS medium. ITS sequences of beneficial fungi were amplified by PCR and taxonomically identified using BLAST against the GenBank nucleotide database. Ten kinds of OMF strains were isolated from B. striata and named R1 to R10. R6 significantly promoted B. striata seeds germination (p < .01). R3 and R6 significantly promoted both the fresh and dry weight increments of B. striata seedlings (p < .05). The ITS sequence of R6 was most similar to the sequence of Serendipita. R3 was identified as Schizothecium fimbriatum by 100% ITS identity. R6 and R3 were beneficial OMF in B. striata.


Assuntos
Micorrizas/isolamento & purificação , Orchidaceae/microbiologia , Germinação , Filogenia , Plântula/crescimento & desenvolvimento , Plântula/microbiologia , Sementes/crescimento & desenvolvimento
14.
Eur J Protistol ; 73: 125666, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32007802

RESUMO

The living morphology, infraciliature, morphogenesis and phylogenetic position of a new hypotrichous ciliate, Heterourosomoida sinica n. sp., discovered in saline soil in Northwest of China, were investigated. Heterourosomoida sinica n. sp. is characterized as follows: body size about 70-95 × 20-30 µm in vivo, ellipsoid or elongate; cortical granules dark green, 0.5 µm across, arranged around dorsal cilia and in short irregular rows on ventral side; consistently 18 frontoventral-transverse cirri; left and right marginal rows composed of 17-24 and 13-21 cirri, respectively; two macronuclear nodules and one or two micronuclei. The detailed morphogenesis of a species of Heterourosomoida is reported for the first time. The ontogenesis on dorsal side is basically similar to that in Urosomoida-species and the process on ventral side is characterized by: 18 frontoventral-transverse cirri develop from six anlagen with the anlagen V and VI formed in the primary mode. Phylogenetic analyses based on SSU rDNA sequence data reveal that Heterourosomoida sinica n. sp. clusters with Kleinstyla dorsicirrata and forms a clade with the type species H. lanceolata.


Assuntos
Hypotrichida/classificação , Filogenia , Solo/parasitologia , China , Hypotrichida/citologia , Hypotrichida/genética , Morfogênese , RNA Ribossômico 18S/genética , Especificidade da Espécie
15.
Bone ; 130: 115108, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31704341

RESUMO

Bone loss has been supposed to be the greatest damage to the health of astronauts. It is generally believed that the mechanical unloading induced by microgravity is the main cause of bone loss. However, besides mechanical unloading, many evidences from animal models and spaceflight missions indicate that microgravity conditions can cause some stress reactions and elevated endogenous glucocorticoid (GC) levels. High levels of GCs can lead to bone loss. This study aimed to investigate whether elevated GC levels are involved in hindlimb unloading (HLU)-induced bone loss in mice. Col2.3-11ß-hydroxysteroid dehydrogenase type 2 (Col2.3-11ß-HSD2) transgenic mice which are characterized by specific blocking GC signaling in mature osteoblasts and osteocytes were used. Male 14-week-old Col2.3-11ß-HSD2 transgenic mice and wild type littermates were tail-suspended or kept under ambulatory conditions. At the endpoint, the tibias were examined by micro-computed tomography and histomorphometry, and bone turnover was analyzed by serum biochemistry, histochemistry staining, immunohistochemistry, and real-time PCR. Mice exposed to unloading occurred a significant increase in serum GC concentrations. Compared with non-unloaded controls, HLU led to a severe damage in cortical bone microstructure and bone strength of the tibia in wild type mice but not transgenic littermates. Osteoblast activity and bone formation were inhibited, whereas osteoclast activity and bone resorption were promoted in the tibial cortical bone of wild type mice following HLU, features absented in transgenic mice. Furthermore, HLU resulted in a significant increase in the number of sclerostin-producing and receptor activator of nuclear factor-κ B ligand (RANKL)-positive osteocytes, and apoptotic osteoblasts and osteocytes in wild type mice of unloading but not in unloaded transgenic mice. In conclusion, cortical bone loss during HLU is mediated through enhancing GC signaling in osteoblasts and osteocytes and subsequently restraining bone formation and activating bone resorption. It suggests that elevated GC levels play an important role in cortical bone loss in response to mechanical unloading.


Assuntos
Glucocorticoides , Osteócitos , Animais , Apoptose , Osso Cortical/diagnóstico por imagem , Elevação dos Membros Posteriores , Masculino , Camundongos , Osteoblastos , Microtomografia por Raio-X
16.
J Eukaryot Microbiol ; 66(5): 730-739, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30737903

RESUMO

Morphogenesis of the soil hypotrich ciliate, Holostichides chardezi Foissner, 1987, collected from southeastern China, was investigated using the protargol staining method. The main morphogenetic events follow a similar process with that of its congeners. Phylogenetic analyses based on the SSU rDNA sequence data indicate that Holostichides is nonmonophyletic; H. chardezi, the type species of Holostichides, clusters with H. heterotypicus, while H. terrae is distinctly separate from these species. H. terrae can be distinguished from H. chardezi (type species of Holostichides) and H. heterotypicus by undulating membranes relatively long and distinctly curved (vs. relatively short and straight), pharynx with (vs. without) rod-shaped structure, and two (vs. more than two) frontoterminal cirri. Therefore, a new genus, Anteholostichides nov. gen., has been proposed for H. terrae. Further, the diagnosis of the genus Holostichides is improved.


Assuntos
Hypotrichida/crescimento & desenvolvimento , Hypotrichida/isolamento & purificação , Filogenia , Solo/parasitologia , China , DNA de Protozoário/genética , DNA Ribossômico/genética , Hypotrichida/classificação , Hypotrichida/genética , Morfogênese
17.
J Eukaryot Microbiol ; 66(2): 334-342, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30059604

RESUMO

Morphogenesis of the hypotrich ciliate Uroleptoides longiseries, isolated from sandy soil beside the Yellow River, Suide, Yulin, Shaanxi Province, China, was investigated using protargol staining. The main events during binary fission are as follows: (1) the long frontoventral row is formed by a single anlage; (2) five frontoventral-transverse cirral anlagen are formed in primary mode; (3) only the posterior part of the parental adoral zone of the membranelles is renewed; and (4) the oral primordium of the opisthe is formed intrakinetally. This is the first detailed record of all stages of morphogenesis for Uroleptoides. We also provide the first record of the small subunit ribosomal DNA (SSU rDNA) sequences for U. longiseries. Phylogenetic analyses based on the SSU rDNA sequences data show that Uroleptoides longiseries clusters with U. magnigranulosa with moderate to high support which together form a clade with Orthoamphisiella breviseries. These three species share the morphogenetic feature of the long frontoventral row being formed by a single anlage.


Assuntos
Hypotrichida/classificação , Filogenia , China , DNA de Protozoário/análise , DNA Ribossômico/análise , Hypotrichida/citologia , Hypotrichida/genética , Morfogênese , Solo
18.
Eur J Protistol ; 66: 166-176, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30326327

RESUMO

The living morphology, infraciliature and morphogenesis of a new urostylid ciliate, Caudiurostyla sinensis gen. nov., spec. nov., isolated from a soil habitat in China, was investigated. The new, monotypic genus is defined by having frontal cirri arranged in a bicorona, distinct transverse cirri, midventral pairs only, buccal cirrus, frontoterminal cirri, multiple marginal cirral rows that replicate independently via within row anlagen formation, more than three dorsal kineties, and caudal cirri. The main morphogenetic features of the new species are: (1) the posterior part of the parental adoral zone is renewed in situ; (2) the marginal cirral rows and dorsal kineties develop intrakinetally; (3) a caudal cirrus is formed at the posterior end of each dorsal kinety; and (4) macronuclear nodules fuse into a single mass during the middle stage. Based on the morphology and morphogenesis, the new genus differs from Pseudourostyla and Hemicycliostyla by presence of caudal cirri.


Assuntos
Hypotrichida/classificação , Hypotrichida/citologia , Solo/parasitologia , Hypotrichida/crescimento & desenvolvimento , Morfogênese , Especificidade da Espécie
19.
Eur J Protistol ; 64: 72-81, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29674179

RESUMO

The living morphology, infraciliature and morphogenetic events of a new soil urostylid ciliate, Australothrix xianiensis nov. spec., collected from Chanba National Wetland Park in Xi'an, China, were studied in vivo and after protargol preparation. Australothrix xianiensis nov. spec. is characterized as follows: about 190-240 × 40-60 µm in life; body pisciform and dark; cortical granules arranged in longitudinal rows on both sides, colourless, rod-shaped and about 2 × 1 µm in size; single contractile vacuole slightly ahead of mid-body with two long collecting canals; macronuclear nodules scattered throughout cytoplasm; adoral zone occupies about 20% of body length, composed of about 32 membranelles; three frontal cirri and one buccal cirrus; two to four midventral pairs and four or five midventral rows, one left and two right marginal rows; four or five dorsal kineties; four or five caudal cirri. The main features of divisional morphogenesis are: (1) each posterior streak generates a midventral row together with the midventral pair; (2) the old adoral zone of membranelles is retained with the exception of the posterior part, which is renewed in situ; the undulating membranes are completely renewed; (3) parental cirri do not contribute to the construction of the oral primordium in the opisthe in very early dividers; (4) two sets of frontoventral cirral anlagen are formed.


Assuntos
Hypotrichida/citologia , Hypotrichida/crescimento & desenvolvimento , Morfogênese , Filogenia , Solo/parasitologia , China , Especificidade da Espécie , Áreas Alagadas
20.
Endocr Connect ; 7(2): 385-394, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29386227

RESUMO

Patients with chronic immune-mediated arthritis exhibit abnormal hypothalamo-pituitary-adrenal (HPA) axis activity. The basis for this abnormality is not known. Immune-mediated arthritis is associated with increased extra-adrenal synthesis of active glucocorticoids by the 11ß-hydroxysteroid dehydrogenase type 1 (11ß-HSD1) enzyme. 11ß-HSD1 is expressed in the central nervous system, including regions involved in HPA axis regulation. We examined whether altered 11ß-HSD1 expression within these regions contributes to HPA axis dysregulation during arthritis. The expression of 11ß-HSD1, and other components of glucocorticoid signaling, were examined in various brain regions and the pituitary gland of mice with experimentally induced arthritis. Two arthritis protocols were employed: The K/BxN spontaneous arthritis model for chronic arthritis and the K/BxN serum transfer arthritis model for acute arthritis. 11ß-HSD1 mRNA (Hsd11b1) was expressed in the hippocampus, hypothalamus, cortex, cerebellum and pituitary gland. Hypothalamic Hsd11b1 expression did not change in response to arthritis in either model. Pituitary Hsd11b1 expression was however significantly increased in both chronic and acute arthritis models. Hippocampal Hsd11b1 was decreased in acute but not chronic arthritis. Chronic, but not acute, arthritis was associated with a reduction in hypothalamic corticotropin-releasing hormone and arginine vasopressin expression. In both models, serum adrenocorticotropic hormone and corticosterone levels were no different from non-inflammatory controls. These findings demonstrate inflammation-dependent regulation of Hsd11b1 expression in the pituitary gland and hippocampus. The upregulation of 11ß-HSD1 expression in the pituitary during both chronic and acute arthritis, and thus, an increase in glucocorticoid negative feedback, could contribute to the abnormalities in HPA axis activity seen in immune-mediated arthritis.

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