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1.
Plant Physiol Biochem ; 208: 108500, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38513518

RESUMO

BREVIS RADIX (BRX) is a small plant-specific and evolutionary conserved gene family with divergent yet partially redundant biological functions including root and shoot growth, stomatal development and tiller angle in plants. We characterized a BRX family gene from wheat (Triticum aestivum) by gain-of-function in Arabidopsis. Overexpression of TaBRXL2A resulted in longer primary roots with increased root meristem size and higher root growth under control and exogenous hormone treatments as compared to wild type (Col-0) plants. Overexpression lines also exhibited significant differences with the wild type such as increased rosette size, higher leaf number and leaf size. At reproductive stage, overexpression lines exhibited wider siliques and higher grain weight per plant. Under drought stress, overexpression lines exhibited enhanced drought tolerance in terms of higher chlorophyll retention and lower oxidative stress, thereby leading to significant recovery from drought stress. The analysis suggests that the inherent lower stomatal density in the leaves of overexpression lines and higher stomatal closure in response to ABA might contribute to lower water loss from the overexpression lines. Furthermore, TaBRXL2A protein showed membrane localization, presence of conserved residues at N-terminal for palmitoylation, and phosphosites in the linker region which are prescribed for its potential role in protophloem differentiation and stomatal lineage. Thus, we identified a TaBRX family gene which is involved in developmental pathways essential for plant growth, and also enhances drought tolerance in Arabidopsis.


Assuntos
Arabidopsis , Arabidopsis/metabolismo , Triticum/genética , Triticum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Resistência à Seca , Estresse Fisiológico/genética , Plantas Geneticamente Modificadas/genética , Tamanho do Órgão , Estômatos de Plantas/fisiologia , Secas , Regulação da Expressão Gênica de Plantas
2.
Sci Adv ; 10(11): eadj2570, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38478622

RESUMO

Ubiquitination plays a crucial role throughout plant growth and development. The E3 ligase DA2 has been reported to activate the peptidase DA1 by ubiquitination, hereby limiting cell proliferation. However, the molecular mechanisms that regulate DA2 remain elusive. Here, we demonstrate that DA2 has a very high turnover and auto-ubiquitinates with K48-linkage polyubiquitin chains, which is counteracted by two deubiquitinating enzymes, UBIQUITIN-SPECIFIC PROTEASE 12 (UBP12) and UBP13. Unexpectedly, we found that auto-ubiquitination of DA2 does not influence its stability but determines its E3 ligase activity. We also demonstrate that impairing the protease activity of DA1 abolishes the growth-reducing effect of DA2. Last, we show that synthetic, constitutively activated DA1-ubiquitin fusion proteins overrule this complex balance of ubiquitination and deubiquitination and strongly restrict growth and promote endoreduplication. Our findings highlight a nonproteolytic function of K48-linked polyubiquitination and reveal a mechanism by which DA2 auto-ubiquitination levels, in concert with UBP12 and UBP13, precisely monitor the activity of DA1 and fine-tune plant organ size.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Tamanho do Órgão , Endorreduplicação , Ubiquitinação , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Proliferação de Células , Endopeptidases/genética
3.
Zootaxa ; 5406(2): 359-372, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38480148

RESUMO

A peculiar new species of the genus Cyclogethes Kirejtshuk, 1979, C. tibialis sp. nov., is described from Southwestern China (Yunnan). The new species appears to be morphologically rather isolated from the other known members of this essentially Oriental genus (including half a dozen species from Northern Indian subcontinent, Northern Indochina, and Southwestern China). However, it could be more closely related to C. abnormis Kirejtshuk, 1979 from Northern India, Indochina, and Southwestern China, and to C. aldridgei Kirejtshuk, 1980 from Northern India and Nepal, from which it is easily distinguished by the more elongate body shape, and by the markedly sinuate hind tibiae in both sexes (a very unusual character state in Meligethinae, where only males of some species exhibit sexual secondary characters in the tibial shape). The new species also differs from other known taxa of the genus by the shape of the male and female genitalia. The larval hostplants of members of Cyclogethes are thus far unknown, although some clues, also involving the new species described herein, may suggest a relationship with small trees or shrubs of the family Asteraceae. Preliminary and incomplete molecular data on a studied member of the genus (C. abnormis) seems to not disagree with a phylogenetic positioning of Cyclogethes in a clade including the African genera Tarchonanthogethes Audisio & Cline, 2009, its allied Afrotropical taxa, and the Palaearctic genera Meligethes Stephens, 1830 and Brassicogethes Audisio & Cline, 2009. The article includes an updated identification key for all six known species of this genus and an updated map of their known geographic distribution.


Assuntos
Besouros , Masculino , Feminino , Animais , Filogenia , Distribuição Animal , China , Estruturas Animais/anatomia & histologia , Tamanho Corporal , Tamanho do Órgão , Pólen
4.
Zootaxa ; 5406(2): 288-296, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38480152

RESUMO

The new species Euphanias sergreevae sp. nov. from the shores of a saline lake in Western Siberia, Russia is described in this paper. The paper examines the type material of two closely related species Euphanias pusanovi Blinstein, 1976 and Euphanias pliginskii Bernhauer, 1912. The species are illustrated with color photographs of the habitus and aedeagus, scanning electron micrographs, and line drawings of the terminalia. A complete distribution map for all members of the genus is given and distribution patterns are discussed.


Assuntos
Besouros , Animais , Sibéria , Distribuição Animal , Estruturas Animais , Tamanho do Órgão , Federação Russa
5.
Zootaxa ; 5423(1): 1-66, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38480303

RESUMO

This study provides a comprehensive account of 40 species (52 valid names and one preoccupied name) of the genus Nemophora Hoffmannsegg, 1798 described or recorded from Myanmar, Thailand, Laos, Cambodia and Vietnam. A key to the species based on external characters and on male genitalia is provided; 14 new species are described: N. auricapitella Kozlov, sp. nov., N. chalcoptera Kozlov, sp. nov., N. karsholti Kozlov, sp. nov., N. kuznetzovi Kozlov, sp. nov., N. meyi Kozlov, sp. nov., N. nielseni Kozlov, sp. nov., N. nieukerkeni Kozlov, sp. nov., N. nigripunctella Kozlov, sp. nov., N. punctifasciella Kozlov, sp. nov., N. rubicunda Kozlov, sp. nov., N. szabokyi Kozlov, sp. nov., N. thailandensis Kozlov, sp. nov., N. vietnamensis Kozlov, sp. nov. and N. yeni Kozlov, sp. nov. Lectotypes are designated for four species, including one junior synonym: Nemotois diplophragma Meyrick, 1938, Nemotois sinicella Walker, 1863, Nemotois cleodoxa Meyrick, 1922 and Adela satrapodes Meyrick, 1894. Eight new synonyms for four species are proposed: Nemophora badagongshana Liao, Hirowatari & Huang in Liao, Hirowatari, Yagi, Wang, Wang & Huang, 2023, syn. nov. of Nemophora aurifera (Butler, 1881); Nemotois chrysocharis Caradja, 1938, syn. nov. of Nemophora sinicella (Walker, 1863); Nemotois diplophragma Meyrick, 1938, syn. nov. of Nemophora melichlorias (Meyrick, 1907); Nemophora basalistriata Liao, Hirowatari & Huang in Liao, Hirowatari, Yagi, Wang, Wang & Huang, 2023, syn. nov. of Nemophora melichlorias (Meyrick, 1907); Nemotois limenites Meyrick, 1914, syn. nov. of Nemophora aurifera (Butler, 1881); Nemophora quadrata Liao, Hirowatari & Huang in Liao, Hirowatari, Yagi, Wang, Wang & Huang, 2023, syn. nov. of Nemophora aurifera (Butler, 1881); Nemotois rubrofascia formosicola Matsumura, 1931, syn. nov. of Nemophora sakaii (Matsumura, 1931); Nemotois servata Meyrick in Caradja, 1925, syn. nov. of Nemophora aurifera (Butler, 1881). Four new combinationsare introduced: Nemophora aglaospila (Meyrick, 1928), comb. nov.; Nemophora cleodoxa (Meyrick, 1922), comb. nov.; Nemophora melichlorias (Meyrick, 1907), comb. nov.; and Nemophora sinicella (Walker, 1863), comb. nov. Of 40 species considered, 16 were recorded in Myanmar, 21 in Thailand, 4 in Laos, 4 in Cambodia and 13 in Vietnam.


Assuntos
Lepidópteros , Mariposas , Masculino , Animais , Camboja , Vietnã , Laos , Mianmar , Tailândia , Distribuição Animal , Estruturas Animais , Tamanho do Órgão
6.
Zootaxa ; 5419(2): 217-244, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38480328

RESUMO

The genus Chisosa Huber, 2000 previously included only three species of small to tiny North American and Caribbean spiders that are rare in collections and poorly studied. Originally placed in the subfamily Ninetinae, Chisosa is currently considered a representative of Arteminae, close to the North American genus Physocyclus Simon, 1893. This placement has been suggested by molecular data, and it affects the interpretation of morphological characters that were originally thought to support the monophyly of Chisosa: they are shared with Physocyclus and thus plesiomorphic for Chisosa. Here we describe a new species from Mexico, C. calapa sp. nov., and restudy in detail the morphology (incl. ultrastructure) of the type species C. diluta (Gertsch & Mulaik, 1940) and of C. caquetio Huber, 2019, based on newly collected material. We document further similarities with Physocyclus but find only weak morphological support for the monophyly of Chisosa (body size reduction and short legs). In addition, we document surprisingly large genetic distances among C. caquetio specimens from Curaao (>14% CO1 K2P distances), possibly indicating species limits. Finally, we propose that the Dominican amber genus Serratochorus Wunderlich, 1988, based on a single male specimen, is also phylogenetically close to Chisosa and should be included in future studies on these enigmatic spiders.


Assuntos
Aranhas , Masculino , Animais , México , Distribuição Animal , Estruturas Animais/anatomia & histologia , Tamanho do Órgão
7.
Zootaxa ; 5418(1): 83-88, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38480369

RESUMO

The gryllacridid genus Woznessenskia Gorochov, 2002 comprises 13 extant species from Asia, with 8 species reported from China and 5 species reported from Vietnam. A new species from Xizang, China, Woznessenskia lianhua sp. nov., is reported in this paper.


Assuntos
Ortópteros , Animais , Distribuição Animal , Estruturas Animais , Tamanho Corporal , Tamanho do Órgão , China
8.
Zootaxa ; 5418(1): 72-82, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38480370

RESUMO

This paper deals with five species of the genus Homogryllacris Liu, 2007 from China, including one new species, i.e. Homogryllacris nigromacula sp. nov. Morphological illustrations of most species and habitus of the new species are provided. Moreover, one geographical population of Homogryllacris yunnana Shi, Guo & Bian, 2012 and intraspecific variation of Homogryllacris platycis Liu & Bian, 2021 are discussed and illustrated. All specimens examined are deposited in the Museum of Hebei University.


Assuntos
Ortópteros , Humanos , Animais , Distribuição Animal , Estruturas Animais/anatomia & histologia , Tamanho Corporal , Tamanho do Órgão , China
9.
Zootaxa ; 5405(1): 80-92, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38480396

RESUMO

Intrageneric taxonomy of genus Heliophanus C.L. Koch, 1833 is revised. Two subgenera are elevated to the generic ranks: Helafricanus Wesoowska, 1986 (type species Heliophanus patellaris Simon, 1901) and Heliocapensis Wesoowska, 1986 (type species Heliophanus peckhami Simon, 1902). Generic name Trapezocephalus Berland & Millot, 1941 is removed from synonyms of Heliophanus and reinstalled as valid genus (type species Heliophanus cassinicola Simon, 1909 = Trapezocephalus aeluriliformis Berland & Millot, 1941). Genera Helafricanus, Heliocapensis, Heliophanus s. str. and Trapezocephalus are redefined, and their updated diagnoses and compositions are given. Seventy-three new combinations are proposed from Heliophanus s. lato. Five specific names are synonymized: Heliophanus thaleri Wesoowska, 2009 with Heliophanus termitophagus Wesoowska & Haddad, 2002, Heliophanus patagiatus albolineatus Kulczyski, 1901 with Heliophanus patagiatus Thorell, 1875, Heliophanus montanus Wesoowska, 2006 with Heliophanus capicola Simon, 1901 (and transferred to Trapezocephalus), Heliophanus berlandi Lawrence, 1937 with Baryphas ahenus Simon, 1902, and Astia hariola L. Koch,1879 with Heliophanus maculatus Karsch,1878, for the latter species Astia maculata (Karsch,1878) comb. nov. is proposed. Heliophanus japonicus Kishida, 1910 is recognized as nomen dubium.


Assuntos
Aranhas , Animais , Tamanho Corporal , Tamanho do Órgão , Distribuição Animal
10.
Zootaxa ; 5405(2): 246-264, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38480387

RESUMO

This paper contributes further studies Chinese cave crickets and describes seven new species and the female sex of Rhaphidophora longitabula Bian, Zhu & Shi, 2017. All the specimens are deposited in Guangxi Normal University.


Assuntos
Araceae , Ortópteros , Animais , Feminino , Distribuição Animal , Estruturas Animais , Tamanho Corporal , Cavernas , China , Tamanho do Órgão
11.
J Affect Disord ; 354: 173-180, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38492647

RESUMO

BACKGROUND: The hippocampus is a crucial brain structure in etiological models of major depressive disorder (MDD). It remains unclear whether sex differences in the incidence and symptoms of MDD are related to differential illness-associated brain alterations, including alterations in the hippocampus. This study investigated divergent the effects of sex on hippocampal subfield alterations in drug-naive patients with MDD. METHODS: High-resolution structural MR images were obtained from 144 drug-naive individuals with MDD early in their illness course and 135 age- and sex-matched healthy controls (HCs). Hippocampal subfields were segmented using FreeSurfer software and analyzed in terms of both histological subfields (CA1-4, dentate gyrus, etc.) and more integrative larger functional subregions (head, body and tail). RESULTS: We observed a significant overall reduction in hippocampal volume in MDD patients, with deficits more prominent deficits in the posterior hippocampus. Differences in anatomic alterations between male and female patients were observed in the CA1-head, presubiculum-body and fimbria in the left hemisphere. Exploratory analyses revealed different patterns of clinical and memory function correlations with histological subfields and functional subregions between male and female patients primarily in the hippocampal head and body. LIMITATIONS: This cross-sectional study cannot clarify the causality of hippocampal alterations or their association with illness risk or onset. CONCLUSIONS: These findings represent the first reported sex-specific alterations in hippocampal histological subfields in patients with MDD early in the illness course prior to treatment. Sex-specific hippocampal alterations may contribute to diverse sex differences in the clinical presentation of MDD.


Assuntos
Transtorno Depressivo Maior , Humanos , Masculino , Feminino , Transtorno Depressivo Maior/tratamento farmacológico , Estudos Transversais , Imageamento por Ressonância Magnética/métodos , Tamanho do Órgão , Hipocampo/diagnóstico por imagem , Hipocampo/patologia
12.
Pediatr Transplant ; 28(2): e14716, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38420659

RESUMO

BACKGROUND: Small-for-size syndrome (SFSS) in pediatric liver transplant recipients, particularly those weighing less than 10 kg, is rare. This report describes a case of a 15-month-old whole liver transplant recipient who suffered SFSS, and systematic literature review was performed to identify outcomes of such cases and potential risk factors for SFSS. CASE PRESENTATION: A 15-month-old toddler with a history of biliary atresia underwent a deceased donor whole liver transplant. The graft weighed 160 g, resulting in a graft-to-recipient weight ratio (GRWR) of 1.6%. The post-operative course was complicated by SFSS, characterized by massive ascites causing hemodynamic instability and compromised hepatic artery flow. Pharmacological intervention with octreotide was initiated, and the patient eventually recovered. CONCLUSION: In small pediatric recipients, especially those weighing less than 10 kg, the native liver body weight ratio (LBWR) is significantly higher. When selecting an appropriately sized graft for these recipients, this higher ratio should be taken into consideration. The literature review suggests that a GRWR of less than 2% is associated with a higher incidence of small-for-size syndrome in small pediatric recipients weighing less than 10 kg.


Assuntos
Doença Hepática Terminal , Transplante de Fígado , Humanos , Criança , Lactente , Doadores Vivos , Tamanho do Órgão , Transplante de Fígado/métodos , Fígado , Síndrome , Sobrevivência de Enxerto , Estudos Retrospectivos
13.
Nat Ecol Evol ; 8(4): 806-816, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38388692

RESUMO

Behavioural innovations can provide key advantages for animals in the wild, especially when ecological conditions change rapidly and unexpectedly. Innovation rates can be compared across taxa by compiling field reports of novel behaviours. Large-scale analyses have shown that innovativeness reduces extinction risk, increases colonization success and is associated with increased brain size and pallial neuron numbers. However, appropriate laboratory measurements of innovativeness, necessary to conduct targeted experimental studies, have not been clearly established, despite decades of speculation on the most suitable assay. Here we implemented a battery of cognitive tasks on 203 birds of 15 passerine species and tested for relationships at the interspecific and intraspecific levels with ecological metrics of innovation and brain size. We found that species better at solving extractive foraging problems had higher technical innovation rates in the wild and larger brains. By contrast, performance on other cognitive tasks often subsumed under the term behavioural flexibility, namely, associative and reversal learning, as well as self-control, were not related to problem-solving, innovation in the wild or brain size. Our study yields robust support for problem-solving as an accurate experimental proxy of innovation and suggests that novel motor solutions are more important than self-control or learning of modified cues in generating technical innovations in the wild.


Assuntos
Passeriformes , Resolução de Problemas , Animais , Tamanho do Órgão , Encéfalo , Comportamento Animal/fisiologia
14.
Poult Sci ; 103(4): 103519, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38359772

RESUMO

We evaluated a single strain Bacillus subtilis BS-9 direct-fed microbial (BSDFM) isolated from camel dung in Eimeria challenged broiler chickens. Seven-hundred d-old Ross 708 male chicks were placed in pens (25 birds/pen) and allocated to 2 treatments (n = 14). From d 0 to 13, control pens received untreated water (-BSDFM), and 2 treated pens received water and 2 mL x 108 colony forming unit/bird/d (+BSDFM); daily water intake (WI) was recorded. On d 9, birds in half (+Eimeria) of pens per treatment received of 1 mL of Eimeria maxima and Eimeria acervulina oocysts orally, and the other half (-Eimeria) sterile saline solution. Birds had ad libitum access to feed and a water line from d 14. Feed intake (FI), body weight (BW) and mortality were recorded for calculating BW gain (BWG) and feed conversion ratio (FCR). On d 14 and 35, samples of birds were necropsied for organ weight and intestinal measurements. Excreta samples were collected from d 14 to 19 for oocyst count. There was no treatment effect (P > 0.05) on growth performance or WI on d 0 to 9. There were interactions between BSDFM and Eimeria on d 19 (P = 0.014) and 29 (P = 0.036) BW with unchallenged +BSDFM birds being heavier than birds in the other treatments. The main effects (P < 0.05) on d 10 to 35 FI, BW, and BWG were such that +BSDFM increased and Eimeria decreased (P < 0.01) these parameters. There was interaction (P = 0.022) between BSDFM and Eimeria on d 10 to 35 FCR such that the FCR of challenged -BSDFM birds was poor than that of unchallenged counterparts, but none differed with +BSDFM birds. There was an interaction (P = 0.039) between BSDFM and Eimeria on d 14 bursa weight with challenged birds exhibiting heavier bursa than unchallenged +BSDFM birds. Eimeria reduced (P = 0.01) and BSDFM (P = 0.002) increased the villi height to crypt depth ratio. Results showed that BSDFM supplementation via water can support the growth performance of broiler chickens challenged with Eimeria and may be a strategy to reduce adverse effects of coccidiosis.


Assuntos
Coccidiose , Eimeria , Doenças das Aves Domésticas , Animais , Masculino , Galinhas , Bacillus subtilis , Camelus , Tamanho do Órgão , Dieta/veterinária , Oocistos , Coccidiose/veterinária , Água , Ração Animal/análise , Suplementos Nutricionais
15.
J Toxicol Environ Health A ; 87(6): 266-273, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38166509

RESUMO

Benzophenone-3 (BP-3, 2-hydroxy-4-methoxybenzophenone, oxybenzone) is one of the most widely used types of benzophenone organic sunscreen. However, this compound is a potentially harmful toxicant. The aim of this study was 2-fold to: (1) utilize a Hershberger bioassay in vivo in castrated male Sprague-Dawley rats to investigate the anti-androgenic activities of BP-3, and (2) use in vitro a methyl tetrazolium assay to compare the toxicity between Leydig cells (TM3 cells) and mouse fibroblast (NIH-3T3) cell lines. In the Hershberger assay, rats were divided into 6 groups (each of n = 7): a vehicle control, negative control, positive control, PB-3 low (40 mg/kg), BP-3 intermediate (200 mg/kg), and BP-3 high (1000 mg/kg)-dose. The weight of the ventral prostate was significantly decreased at BP-3 doses of 200 or 1,000 mg/kg/day. In addition, the levator anibulbocavernosus muscle weights were also significantly reduced at BP-3 doses of 40, 200, or 1,000 mg/kg/day. In the MTT assay, the viability of NIH-3T3 mouse fibroblast cells was within the normal range. However, the TM3 mouse testis Leydig cell viability was significantly lowered in a concentration-dependent manner. Therefore, data indicate that BP-3 might exert in vivo anti-androgenic and in vitro cytotoxic effects in cells associated with the male reproductive system compared to normal non-reproductive cells.Abbreviation: BP-3: benzophenone-3; CG: Cowper's gland; DMEM: Dulbecco's modified Eagle's medium; DMSO: dimethyl sulfoxide; GP: glans penis; LABC: levator anibulbocavernosus muscle; MTT: methyl tetrazolium; NC: negative control; PC: positive control; SV: seminal vesicle; TP: testosterone propionate; VC: vehicle control; VP: ventral prostate.


Assuntos
Antineoplásicos , Orquiectomia , Camundongos , Ratos , Masculino , Animais , Ratos Sprague-Dawley , Antagonistas de Androgênios/farmacologia , Benzofenonas/toxicidade , Antineoplásicos/farmacologia , Tamanho do Órgão , Genitália Masculina
16.
Brain Res ; 1828: 148768, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38244756

RESUMO

A study on primates has established that gyral size is largely independent of overall brain size. Building on this-and other research suggesting that brain gyrification may mitigate the effects of head impacts-our study aims to explore potential correlations between gyral size and the risk of head impact across a diverse range of mammalian species. Our findings corroborate the idea that gyral sizes are largely independent of brain sizes, especially among species with larger brains, thus extending this observation beyond primates. Preliminary evidence also suggests a correlation between an animal's gyral size and its lifestyle, particularly in terms of head-impact risk. For instance, goats, known for their headbutting behaviors, exhibit smaller gyral sizes. In contrast, species such as manatees and dugongs, which typically face lower risks of head impact, have lissencephalic brains. Additionally, we explore mechanisms that may explain how narrower gyral sizes could offer protective advantages against head impact. Finally, we discuss a possible trade-off associated with gyrencephaly.


Assuntos
Mamíferos , Primatas , Animais , Tamanho do Órgão , Encéfalo
17.
Transl Psychiatry ; 14(1): 44, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38245522

RESUMO

Hippocampal volumetric reductions are observed across the psychosis spectrum, with interest in the localisation of these reductions within the hippocampal subfields increasing. Deficits of the CA1 subfield in particular have been implicated in the neuropathophysiology of psychotic disorders. Investigating the trajectory of these abnormalities in healthy adolescents reporting sub-threshold psychotic experiences (PE) can provide insight into the neural mechanisms underlying psychotic symptoms without the potentially confounding effects of a formal disorder, or antipsychotic medication. In this novel investigation, a sample of 211 young people aged 11-13 participated initially in the Adolescent Brain Development study. PE classification was determined by expert consensus at each timepoint. Participants underwent neuroimaging at 3 timepoints, over 6 years. 78 participants with at least one scan were included in the final sample; 33 who met criteria for a definite PE at least once across all the timepoints (PE group), and 45 controls. Data from bilateral subfields of interest (CA1, CA2/3, CA4/DG, presubiculum and subiculum) were extracted for Linear Mixed Effects analyses. Before correction, subfield volumes were found to increase in the control group and decrease in the PE group for the right CA2 and CA2/3 subfields, with moderate to large effect sizes (d = -0.61, and d = -0.79, respectively). Before correction, right subiculum and left presubiculum volumes were reduced in the PE group compared to controls, regardless of time, with moderate effect sizes (d = -0.52, and d = -0.59, respectively). However, none of these effects survived correction. Severity of symptoms were not associated with any of the noted subfields. These findings provide novel insight to the discussion of the role of hippocampal subfield abnormalities in the pathophysiology underlying psychotic experiences.


Assuntos
Antipsicóticos , Transtornos Psicóticos , Adolescente , Humanos , Tamanho do Órgão , Hipocampo/diagnóstico por imagem , Transtornos Psicóticos/diagnóstico por imagem , Neuroimagem/métodos , Imageamento por Ressonância Magnética/métodos
18.
PLoS Biol ; 22(1): e3002471, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38295340

RESUMO

The building of fully functional and well-proportioned individuals relies on the precise regulation of the size of each of their constituting organs. A new study unravels a mechanism that confers precision to size regulation of the adult Drosophila eye through morphogen-mediated modulation of cell survival.


Assuntos
Proteínas de Drosophila , Drosophila , Animais , Humanos , Drosophila/metabolismo , Proteínas de Drosophila/metabolismo , Retroalimentação , Tamanho do Órgão , Regulação da Expressão Gênica no Desenvolvimento , Proteína Morfogenética Óssea 2
19.
PLoS Biol ; 22(1): e3002450, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38289899

RESUMO

Biological processes are intrinsically noisy, and yet, the result of development-like the species-specific size and shape of organs-is usually remarkably precise. This precision suggests the existence of mechanisms of feedback control that ensure that deviations from a target size are minimized. Still, we have very limited understanding of how these mechanisms operate. Here, we investigate the problem of organ size precision using the Drosophila eye. The size of the adult eye depends on the rates at which eye progenitor cells grow and differentiate. We first find that the progenitor net growth rate results from the balance between their proliferation and apoptosis, with this latter contributing to determining both final eye size and its variability. In turn, apoptosis of progenitor cells is hampered by Dpp, a BMP2/4 signaling molecule transiently produced by early differentiating retinal cells. Our genetic and computational experiments show how the status of retinal differentiation is communicated to progenitors through the differentiation-dependent production of Dpp, which, by adjusting the rate of apoptosis, exerts a feedback control over the net growth of progenitors to reduce final eye size variability.


Assuntos
Proteínas de Drosophila , Drosophila , Animais , Drosophila/genética , Drosophila melanogaster , Proteínas de Drosophila/genética , Tamanho do Órgão , Retroalimentação , Olho , Retina , Apoptose/genética
20.
Arthropod Struct Dev ; 78: 101329, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38171085

RESUMO

Factors regulating larval growth and determinants of adult body size are described for several holometabolous insects, but less is known about brain size scaling through development. Here we use the isotropic fractionation ("brain soup") method to estimate the number of brain cells and cell density for the whitelined sphinx moth (Lepidoptera: Hyles lineata) from the first instar through the adult stage. We measure mass and brain cell number and find that, during the larval stages, body mass shows an exponential relationship with head width, while the total number of brain cells increases asymptotically. Larval brain cell number increases by a factor of ten from nearly 8000 in the first instar to over 80,000 in the fifth instar. Brain cell number increases by another factor of 10 during metamorphosis, with the adult brain containing more than 900,000 cells. This is similar to increases during development in the vinegar fly (Drosophila melanogaster) and the black soldier fly (Hermetia illucens). The adult brain falls slightly below the brain-to-body allometry for wasps and bees but is comparable in the number of cells per unit brain mass, indicating a general conservation of brain cell density across these divergent lineages.


Assuntos
Mariposas , Vespas , Abelhas , Animais , Drosophila melanogaster , Tamanho do Órgão , Larva , Contagem de Células
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