Optimization of retinin expression and the application with wax emulsion in nanocoatings / 生物工程学报

Anti-reflective nanocoatings that mimic the eyes of fruit flies are biodegradable materials with great market potential for a variety of optical devices that require anti-reflective properties. Microbial expression of retinin provides a new idea for the preparation of nanocoatings under mild conditions compared to physicochemical methods. However, the current expression level of retinin, the key to anti-reflective coating, is low and difficult to meet mass production. In this study, we analyzed and screened the best expression hosts for Drosophila-derived retinin protein, and optimized its expression. Chinese hamster ovary (CHO) cells were identified as the efficient expression host of retinin, and purified retinin protein was obtained. At the same time, the preparation method of lanolin nanoemulsion was explored, and the best anti-reflective ability of the nano-coating was determined when the ratio of specific concentration of retinin protein and wax emulsion was 16:4, the pH of the nano-coating formation system was 7.0, and the temperature was 30 ℃. The enhanced antireflective ability and reduced production cost of artificial antireflective nanocoatings by determining the composition of nanocoatings and optimizing the concentration, pH and temperature of system components may facilitate future application of artificial green degradable antireflective coatings.

A Neural Circuit Controlling Virgin Female Aggression Induced by Mating-related Cues in Drosophila / 神经科学通报·英文版

Females increase aggression for mating opportunities and for acquiring reproductive resources. Although the close relationship between female aggression and mating status is widely appreciated, whether and how female aggression is regulated by mating-related cues remains poorly understood. Here we report an interesting observation that Drosophila virgin females initiate high-frequency attacks toward mated females. We identify 11-cis-vaccenyl acetate (cVA), a male-derived pheromone transferred to females during mating, which promotes virgin female aggression. We subsequently reveal a cVA-responsive neural circuit consisting of four orders of neurons, including Or67d, DA1, aSP-g, and pC1 neurons, that mediate cVA-induced virgin female aggression. We also determine that aSP-g neurons release acetylcholine (ACh) to excite pC1 neurons via the nicotinic ACh receptor nAChRα7. Together, beyond revealing cVA as a mating-related inducer of virgin female aggression, our results identify a neural circuit linking the chemosensory perception of mating-related cues to aggressive behavior in Drosophila females.

The regulatory relationship between RagA and Nprl2 in Drosophila gut development / 生物工程学报

The gastrointestinal tract is the largest digestive organ and the largest immune organ and detoxification organ, which is vital to the health of the body. Drosophila is a classic model organism, and its gut is highly similar to mammalian gut in terms of cell composition and genetic regulation, therefore can be used as a good model for studying gut development. target of rapmaycin complex 1 (TORC1) is a key factor regulating cellular metabolism. Nprl2 inhibits TORC1 activity by reducing Rag GTPase activity. Previous studies have found that nprl2 mutated Drosophila showed aging-related phenotypes such as enlarged foregastric and reduced lifespan, which were caused by over-activation of TORC1. In order to explore the role of Rag GTPase in the developmental defects of the gut of nprl2 mutated Drosophila, we used genetic hybridization combined with immunofluorescence to study the intestinal morphology and intestinal cell composition of RagA knockdown and nprl2 mutated Drosophila. The results showed that RagA knockdown alone could induce intestinal thickening and forestomach enlargement, suggesting that RagA also plays an important role in intestinal development. Knockdown of RagA rescued the phenotype of intestinal thinning and decreased secretory cells in nprl2 mutants, suggesting that Nprl2 may regulate the differentiation and morphology of intestinal cells by acting on RagA. Knockdown of RagA did not rescue the enlarged forestomach phenotype in nprl2 mutants, suggesting that Nprl2 may regulate forestomach development and intestinal digestive function through a mechanism independent of Rag GTPase.

Resveratrol and Sir2 Reverse Sleep and Memory Defects Induced by Amyloid Precursor Protein / 神经科学通报·英文版

Resveratrol (RES), a natural polyphenolic phytochemical, has been suggested as a putative anti-aging molecule for the prevention and treatment of Alzheimer's disease (AD) by the activation of sirtuin 1 (Sirt1/Sir2). In this study, we tested the effects of RES and Sirt1/Sir2 on sleep and courtship memory in a Drosophila model by overexpression of amyloid precursor protein (APP), whose duplications and mutations cause familial AD. We found a mild but significant transcriptional increase of Drosophila Sir2 (dSir2) by RES supplementation for up to 17 days in APP flies, but not for 7 days. RES and dSir2 almost completely reversed the sleep and memory deficits in APP flies. We further demonstrated that dSir2 acts as a sleep promotor in Drosophila neurons. Interestingly, RES increased sleep in the absence of dSir2 in dSir2-null mutants, and RES further enhanced sleep when dSir2 was either overexpressed or knocked down in APP flies. Finally, we showed that Aβ aggregates in APP flies were reduced by RES and dSir2, probably via inhibiting Drosophila β-secretase (dBACE). Our data suggest that RES rescues the APP-induced behavioral deficits and Aβ burden largely, but not exclusively, via dSir2.

Analysis of a Chinese pedigree with autosomal dominant Charcot-Marie-Tooth disease type 2A2A / 中华医学遗传学杂志

OBJECTIVE@#To explore the genetic basis of a pedigree affected with peroneal muscular atrophy.@*METHODS@#Neuroelectrophysiological examination and whole exome sequencing were carried out for the proband, a six-year-and-ten-month-old boy. Suspected variant was verified in his family members through Sanger sequencing. Bioinformatic analysis was carried to predict the conservation of amino acid sequence and impact of the variant on the protein structure and function.@*RESULTS@#Electrophysiological examination showed demyelination and axonal changes of motor and sensory nerve fibers. A heterozygous missense c.1066A>G (p. Thr356Ala) variant was found in exon 11 of the MFN2 gene in the proband and his mother, but not in his sister and father. Bioinformatic analysis using PolyPhen-2 and Mutation Taster software predicted the variant to be pathogenic, and that the sequence of variation site was highly conserved among various species. Based no the American College of Medical Genetics and Genomics standards and guidelines, the c.1066A>G (p. Thr356Ala) variant of MFN2 gene was predicted to be likely pathogenic (PS1+ PM2+ PP3+ PP4).@*CONCLUSION@#The heterozygous missense c.1066A>G (p.Thr356Ala) variant of the MFN2 gene probably underlay the disease in the proband, and the results have enabled genetic counseling and prenatal diagnosis for this family.

Protective Effect of Alkaloid-rich Extract of Brimstone Tree (Morinda lucida) on Neurotoxicity in the Fruit-fly (Drosophila melanogaster) Model

Afr. J. Biomed. Res. Vol. 24 (May, 2021); 257- 263 Research Article Protective Effect of Alkaloid-rich Extract of Brimstone Tree (Morinda lucida) on Neurotoxicity in the Fruit-fly (Drosophila melanogaster) Model Nwanna E.E. Functional Food, Nutraceutical and Phytomedicine unit Department of Biochemistry, Federal University of Technology Akure PMB 704, Nigeria ABSTRACT Brimstone plant is one of the medicinal plants found in Nigeria used in fore-lore medicine with little scientific information on its alkaloid constituents. This study was aimed at investigating the effect of alkaloid-rich compounds from the plant in manganese- induced (MgCl2) neurotoxicity in the fruit fly. In addition, alkaloid compounds will be characterized using gas chromatograph coupled with flame ionization detector (GC-FID). Alkaloid-rich extract was prepared by solvent extraction method, fruit flies were pre-treated with the extract (0.5 ­ 1.0mg/ml) in a fortified diet before induction with MgCl2. The survival rate and negative geotaxis were observed. Thereafter, the activity of acetylcholinesterase (AChE) enzyme, antioxidantive potentials in in -vivo reactive oxygen species (ROS) thiobarbituric acid reactive species (TBARS), total thiol content, nitric oxide (NO*), hydroxyl oxide (OH*) scavenging ability, ferric reducing antioxidant property (FRAP) and 2, 2'-azino-bis (3-ethylbenzthiazoline-6- sulphonic acid) (ABTs*) radical scavenging ability were carried out on the flies' homogenate. Results obtained revealed that the alkaloid-rich extract regulated the neuro-protective activity of AchE, reduced the reactive oxygen species level in the induced flies with an increased in antioxidantive potential, higher survival rate and increases in the life span of the flies with 50% reduction in the mortality rate. The GC-MS showed a total of (1.55/100mg) of different plant-derived alkaloids such as dicentrine, atropine, aporphine. These alkaloids-rich compounds were found to have anti-oxidative, anti-nociceptive, anti-inflammatory and anti- cholinergic activities. In conclusion, this study suggests that alkaloids from brimstone plant could be the reason for the observed biological activities for the prevention of neuronal related complications.

Formation of FADD amyloid fiber and its role in immune signaling in Drosophila melanogaster / 生物工程学报

In this research, we studied the formation of Drosophila melanogaster FADD (Fas-associated death domain-containing protein) amyloid fiber and its influence on signal transduction in IMD (Immune deficiency) signaling pathway to better understand the regulation mechanism of Drosophila innate immune signaling pathway, which will provide reference for the immune regulation in other species. First, we purified dFADD protein expressed in Escherichia coli and performed Sulfur flavin T binding and transmission electron microscopy to identify the dFADD amyloid fibers formed in vitro. Then we investigated the formation of dFADD polymers in S2 cells using SDD-AGE and confocal microscope. We also constructed dFADD mutants to find out which domain is essential to fiber formation and its effect on IMD signal transduction. Our results revealed that dFADD could be polymerized to form amyloid fiber polymers in vitro and inside the cells. Formation of fibers relies on DED (Death-effector domain) domain of dFADD, since DED domain-deleted mutant existed as a monomer. Dual luciferase reporter assay showed that intact DED domain was required for the induction of downstream antimicrobial peptides, indicating that fiber formation was the key to IMD signal transduction. Our study revealed the role of dFADD in mediating the cascade between IMD and Dredd in the IMD signaling pathway by forming amyloid fibers, suggesting an evolutionarily conserved regulatory mechanism of innate immune signaling pathway.

Repeated Failure in Reward Pursuit Alters Innate Drosophila Larval Behaviors / 神经科学通报·英文版

Animals always seek rewards and the related neural basis has been well studied. However, what happens when animals fail to get a reward is largely unknown, although this is commonly seen in behaviors such as predation. Here, we set up a behavioral model of repeated failure in reward pursuit (RFRP) in Drosophila larvae. In this model, the larvae were repeatedly prevented from reaching attractants such as yeast and butyl acetate, before finally abandoning further attempts. After giving up, they usually showed a decreased locomotor speed and impaired performance in light avoidance and sugar preference, which were named as phenotypes of RFRP states. In larvae that had developed RFRP phenotypes, the octopamine concentration was greatly elevated, while tβh mutants devoid of octopamine were less likely to develop RFRP phenotypes, and octopamine feeding efficiently restored such defects. By down-regulating tβh in different groups of neurons and imaging neuronal activity, neurons that regulated the development of RFRP states and the behavioral exhibition of RFRP phenotypes were mapped to a small subgroup of non-glutamatergic and glutamatergic octopaminergic neurons in the central larval brain. Our results establish a model for investigating the effect of depriving an expected reward in Drosophila and provide a simplified framework for the associated neural basis.

Taurine Transporter dEAAT2 is Required for Auditory Transduction in Drosophila / 神经科学通报·英文版

Drosophila dEAAT2, a member of the excitatory amino-acid transporter (EAAT) family, has been described as mediating the high-affinity transport of taurine, which is a free amino-acid abundant in both insects and mammals. However, the role of taurine and its transporter in hearing is not clear. Here, we report that dEAAT2 is required for the larval startle response to sound stimuli. dEAAT2 was found to be enriched in the distal region of chordotonal neurons where sound transduction occurs. The Ca imaging and electrophysiological results showed that disrupted dEAAT2 expression significantly reduced the response of chordotonal neurons to sound. More importantly, expressing dEAAT2 in the chordotonal neurons rescued these mutant phenotypes. Taken together, these findings indicate a critical role for Drosophila dEAAT2 in sound transduction by chordotonal neurons.

Hierarchical Control of Drosophila Sleep, Courtship, and Feeding Behaviors by Male-Specific P1 Neurons / 神经科学通报·英文版

Animals choose among sleep, courtship, and feeding behaviors based on the integration of both external sensory cues and internal states; such choices are essential for survival and reproduction. These competing behaviors are closely related and controlled by distinct neural circuits, but whether they are also regulated by shared neural nodes is unclear. Here, we investigated how a set of male-specific P1 neurons controls sleep, courtship, and feeding behaviors in Drosophila males. We found that mild activation of P1 neurons was sufficient to affect sleep, but not courtship or feeding, while stronger activation of P1 neurons labeled by four out of five independent drivers induced courtship, but only the driver that targeted the largest number of P1 neurons affected feeding. These results reveal a common neural node that affects sleep, courtship, and feeding in a threshold-dependent manner, and provide insights into how competing behaviors can be regulated by a shared neural node.

The emerging roles of the DDX41 protein in immunity and diseases

RNA helicases are involved in almost every aspect of RNA, from transcription to RNA decay. DExD/H-box helicases comprise the largest SF2 helicase superfamily, which are characterized by two conserved RecA-like domains. In recent years, an increasing number of unexpected functions of these proteins have been discovered. They play important roles not only in innate immune response but also in diseases like cancers and chronic hepatitis C. In this review, we summarize the recent literatures on one member of the SF2 superfamily, the DEAD-box protein DDX41. After bacterial or viral infection, DNA or cyclic-di-GMP is released to cells. After phosphorylation of Tyr414 by BTK kinase, DDX41 will act as a sensor to recognize the invaders, followed by induction of type I interferons (IFN). After the immune response, DDX41 is degraded by the E3 ligase TRIM21, using Lys9 and Lys115 of DDX41 as the ubiquitination sites. Besides the roles in innate immunity, DDX41 is also related to diseases. An increasing number of both inherited and acquired mutations in DDX41 gene are identified from myelodysplastic syndrome and/or acute myeloid leukemia (MDS/AML) patients. The review focuses on DDX41, as well as its homolog Abstrakt in Drosophila, which is important for survival at all stages throughout the life cycle of the fly.

Effects of Gardenia jasminoides extracts on cognition and innate immune response in an adult Drosophila model of Alzheimer's disease / 中国天然药物

Herbal extracts have been extensively used worldwide for their application on memory improvement, especially among aged and memory-deficit populations. In the present study, the memory loss induced by human Abeta protein over-expression in fruitfly Alzheimer's disease (AD) model was rescued by multiple extracts from Gardenia jasminoides. Three extracts that rich with gardenia yellow, geniposide, and gardenoside components showed distinct rescue effect on memory loss. Further investigation on adding gardenoside into a formula of Ganoderma lucidum, Panax notoginseng and Panax ginseng (GPP) also support its therapeutic effects on memory improvement. Interestingly, the application of GPP and gardenoside did not alter the accumulation of Abeta proteins but suppressed the expression of immune-related genes in the brain. These results revealed the importance and relevancy of anti-inflammation process and the underlying mechanisms on rescuing memory deficits, suggesting the potential therapeutic use of the improved GPP formulation in improving cognition in defined population in the future.

Fatores psicossociais e socioeconômicos relacionados à insônia e menopausa: Estudo Pró-Saúde / Psychosocial and socioeconomic factors related to insomnia and menopause: Pró-Saúde Study / Factores psicosociales y socioeconómicos relacionados con el insomnio y la menopausia: Estudio Pro-Salud

Foi avaliada a associação entre menopausa e insônia e a influência de variáveis socioeconômicas e psicossociais, em estudo transversal com 2.190 funcionárias de uma universidade (Estudo Pró-Saúde), a partir de um questionário autopreenchível com variáveis sobre menopausa, insônia, transtorno mental comum, eventos de vida estressantes, apoio social e variáveis socioeconômicas. Odds ratios foram calculados por meio de regressão logística multivariada, com desfecho politômico. Após ajuste para potenciais confundidoras sociodemográficas, mulheres na menopausa há mais de 60 meses apresentaram maior chance de reportar queixas de sono frequentes (OR entre 1,53 e 1,86) do que as que estavam na menopausa há menos de 60 meses. Após os ajustes, no primeiro grupo, para as variáveis psicossociais, a magnitude dos ORs reduziu para 1,53 (IC95%: 0,92-2,52) para dificuldade em iniciar o sono, 1,81 (IC95%: 1,09-2,98) para dificuldade em manter o sono e 1,71 (IC95%: 1,08-2,73) para queixa geral de insônia. Fatores psicossociais podem mediar a manifestação da insônia em mulheres na menopausa.

This study evaluated the association between insomnia and menopausal status and the influence of socioeconomic and psychosocial variables on this association in a cross-sectional analysis of 2,190 university employees (the Pró-Saúde Study). A self-administered questionnaire was used, covering menopausal status, complaints of insomnia, common mental disorders, stressful life events, social support, and socioeconomic variables. Odds ratios were calculated using logistic regression with a polytomous outcome. After adjusting for potential socio-demographic confounders, women who had entered menopause more than 60 months previously were more likely to report complaints with sleep (OR 1.53-1.86) as compared to women in menopause for less than 60 months. After adjusting for psychosocial variables, in the first group the ORs decreased to 1.53 (95%CI: 0.92-2.52) for difficulty initiating sleep, 1.81 (95%CI: 1.09-2.98) for difficulty maintaining sleep, and 1.71 (95%CI: 1.08-2.73) for general complaints of insomnia. Psychosocial factors can mediate the manifestation of insomnia among menopausal women.

En este estudio se evaluó la asociación entre insomnio y menopausia y la influencia de las variables socioeconómicas y psicosociales, en un estudio transversal con 2.190 mujeres de una universidad (Estudio Pro-Salud), a partir de un cuestionario autoadministrado con variables de la menopausia, insomnio, trastornos mentales, situaciones de estrés vital, apoyo social y variables socioeconómicas. Se calcularon los odds ratio mediante regresión logística multivariante con desenlace politómico. Después de ajustar por factores de confusión sociodemográficos potenciales, las mujeres menopáusicas desde hace más de 60 meses fueron más propensas a reportar quejas frecuentes de sueño (OR entre 1,53 y 1,86) que las menopáusicas hace menos de 60 meses. Después de los ajustes, en el primer grupo, para las variables psicosociales la magnitud de los OR se redujo a 1,53 (IC95%: 0,92-2,52) para la dificultad para iniciar el sueño, un 1,81 (IC95%: 1,09-2,98) para mantener el sueño y un 1,71 (IC95%: 1,08-2,73) para las quejas de insomnio en general. Los factores psicosociales pueden mediar en la manifestación del insomnio en las mujeres menopáusicas.

The homeodomain of Eyeless regulates cell growth and antagonizes the paired domain-dependent retinal differentiation function

Pax6 and its Drosophila homolog Eyeless (Ey) play essential roles during eye development. Ey/Pax6 contains two distinct DNA binding domains, a Paired domain (PD) and a Homeodomain (HD). While Ey/Pax6 PD is required for the expression of key regulators of retinal development, relatively little is known about the HD-dependent Ey function. In this study, we used the UAS/GAL4 system to determine the functions of different Ey domains on cell growth and on retinal development. We showed that Ey can promote cell growth, which requires the HD but not the PD. In contrast, the ability of Ey to activate Ato expression and induce ectopic eye formation requires the PD but not the HD. Interestingly, deletion of the HD enhanced Ey-dependent ectopic eye induction while overexpression of the HD only Ey forms antagonizes ectopic eye induction. These studies revealed a novel function of Ey HD on cell growth and a novel antagonistic effect of Ey HD on Ey PD-dependent eye induction. We further show the third helix of the Ey HD can directly interact with the RED subdomain in Ey PD and that deletion of the HD increased the binding of Ey PD to its target. These results suggest that the direct interaction between the HD and the PD potentially mediates their antagonistic effects. Since different Ey splicing forms are expressed in overlapping regions during normal development, we speculate that the expression ratios of the different Ey splice forms potentially contribute to the regulation of growth and differentiation of these tissues.

Comparison of human and Drosophila atlastin GTPases

Formation of the endoplasmic reticulum (ER) network requires homotypic membrane fusion, which involves a class of atlastin (ATL) GTPases. Purified Drosophila ATL is capable of mediating vesicle fusion in vitro, but such activity has not been reported for any other ATLs. Here, we determined the preliminary crystal structure of the cytosolic segment of Drosophila ATL in a GDP-bound state. The structure reveals a GTPase domain dimer with the subsequent three-helix bundles associating with their own GTPase domains and pointing in opposite directions. This conformation is similar to that of human ATL1, to which GDP and high concentrations of inorganic phosphate, but not GDP only, were included. Drosophila ATL restored ER morphology defects in mammalian cells lacking ATLs, and measurements of nucleotide-dependent dimerization and GTPase activity were comparable for Drosophila ATL and human ATL1. However, purified and reconstituted human ATL1 exhibited no in vitro fusion activity. When the cytosolic segment of human ATL1 was connected to the transmembrane (TM) region and C-terminal tail (CT) of Drosophila ATL, the chimera still exhibited no fusion activity, though its GTPase activity was normal. These results suggest that GDP-bound ATLs may adopt multiple conformations and the in vitro fusion activity of ATL cannot be achieved by a simple collection of functional domains.

Binding of human SWI1 ARID domain to DNA without sequence specificity: A molecular dynamics study / 华中科技大学学报（医学）（英德文版）

SWI1 is a member of a new class of tumor DNA-binding proteins named as the AT-rich interaction domain family (ARID), and considered to bind with AT base pairs specifically. Genomic and functional data support ARID1A as a tumor suppressor because ARID1A/BAF250a (SWI1) subunit of the SWI/SNF chromatin-remodeling complex has emerged as recurrently mutated in a broad array of tumor types. But the crystal structure of SWI1 has not been solved as yet. Using docking and molecular dynamics, we predicted the DNA interaction pattern of human SWI1 ARID and made comparisons with the other two representative ARID family members, human Mrf-2 ARID and Drosophila Dri ARID. Dynamic results revealed that the N-terminal and loop L1 of SWI1 ARID bound with the DNA major groove, while the loop L2 and helix H6 bound with the minor groove. Moreover, it was found that SWI1 ARID bound with DNA apparently in a sequence-nonspecific manner. It was concluded that SWI1 ARID can form stable complex with sequence-nonspecific DNA segment comparing to Mrf-2 ARID/DNA and Dri ARID/DNA sequence-specific complexes.

Recent advances of studies on abnormal HOX gene in myelodysplastic syndromes and its molecular mechanisms / 中国实验血液学杂志

HOX gene encodes a group of homeodomain transcription factors which are highly conserved. The caudal-type homeobox (CDX) , ten-eleven translocation (TET) genes and polycomb group (PcG) , trithorax group (TrxG) proteins act as upstream regulators of HOX genes that manipulate the targeted gene expression through genetic and epigenetic mechanisms. The abnormal expression of HOX genes and their fusions contribute to myelodysplastic syndromes (MDS) pathogenesis. Aberrant DNA methylation and NUP98-HOX translocation serve as molecular mediators of dysfunction in MDS which can be used for the evaluation of biology and therapy. This article provides an overview of recent advances of studies on HOX gene and its abnormal molecular mechanisms, as well as potential correlation with MDS.

Effect of curcumin on aged Drosophila melanogaster: a pathway prediction analysis / 中国结合医学杂志

<p><b>OBJECTIVE</b>To re-analyze the data published in order to explore plausible biological pathways that can be used to explain the anti-aging effect of curcumin.</p><p><b>METHODS</b>Microarray data generated from other study aiming to investigate effect of curcumin on extending lifespan of Drosophila melanogaster were further used for pathway prediction analysis. The differentially expressed genes were identified by using GeneSpring GX with a criterion of 3.0-fold change. Two Cytoscape plugins including BisoGenet and molecular complex detection (MCODE) were used to establish the protein-protein interaction (PPI) network based upon differential genes in order to detect highly connected regions. The function annotation clustering tool of Database for Annotation, Visualization and Integrated Discovery (DAVID) was used for pathway analysis.</p><p><b>RESULTS</b>A total of 87 genes expressed differentially in D. melanogaster melanogaster treated with curcumin were identified, among which 50 were up-regulated significantly and 37 were remarkably down-regulated in D. melanogaster melanogaster treated with curcumin. Based upon these differential genes, PPI network was constructed with 1,082 nodes and 2,412 edges. Five highly connected regions in PPI networks were detected by MCODE algorithm, suggesting anti-aging effect of curcumin may be underlined through five different pathways including Notch signaling pathway, basal transcription factors, cell cycle regulation, ribosome, Wnt signaling pathway, and p53 pathway.</p><p><b>CONCLUSION</b>Genes and their associated pathways in D. melanogaster melanogaster treated with anti-aging agent curcumin were identified using PPI network and MCODE algorithm, suggesting that curcumin may be developed as an alternative therapeutic medicine for treating aging-associated diseases.</p>

Total clipless cholecystectomy by means of harmonic sealing / Colecistectomia laparoscópica totalmente ultrassônica sem uso de clipe metálico

BACKGROUND: In traditional laparoscopic cholecistectomy, the cystic duct and artery are commonly closed by metallic clips just before their division. Although the placement of these clips for occluding cystic artery and duct can be considered safe, biliary leaks and bleeding may occur especially by its dislodgement. AIM: To report a prospective case-series in total clipless cholecystectomy by means of harmonic shears for closure and division of the artery and cystic duct as well removal of the gallbladder from the liver. METHODS: Was evaluate a series of 125 patients who underwent laparoscopic cholecystectomy where the sealing and division of cystic artery and duct was carried out only by harmonic shears. The intact extracted gallbladder was submitted to a reverse pressure test for assessment of the technique safety by means of CO2 insuflation. RESULTS: The most common indication for surgery was gallstones. The mean operative time was 26 min and all gallbladders were dissected intact from the liver bed. There was no mortality and the overall morbidity rate was 0.8% with no hemorrhage or leaks. The reverse pressure test showed that all specimens support at least 36-mmHg of pressure without leaking. CONCLUSION: The harmonic shears is effective and safe in laparoscopic cholecystectomy as a sole instrument for sealing and division of the artery and cystic duct. The main advantages could be related to the safety and decreased operative time. .

RACIONAL: A colecistectomia laparoscópica na técnica tradicional oclui o ducto cístico e a artéria cística por clipes cirúrgicos, que podem se deslocar ou desprender no pós-operatório, possibilitando a ocorrência de fístula biliar ou hemorragia. OBJETIVO: Relato prospectivo de série de casos de colecistectomias laparoscópicas sem uso de clipe cirúrgico, sendo que a ligadura e secção da artéria cística e do ducto cístico foram realizadas por meio de bisturi ultrassônico. MÉTODO: Foram incluídos 125 pacientes submetidos à colecistectomia laparoscópica sem utilização de clipe cirúrgico metálico, onde a ligadura da artéria e do ducto cístico e também a remoção da vesícula biliar de seu leito hepático foram realizadas por meio de tesoura ultrassônica. Realizou-se teste de pressão reversa na vesícula biliar removida intacta do leito hepático para verificar a segurança da técnica. RESULTADOS: A principal indicação cirúrgica foi a colelitíase. O tempo cirúrgico médio foi de 26 min e todas as vesículas biliares foram retiradas intactas do leito hepático. Não houve mortalidade e a taxa global de morbidade foi de 0,8%, sem hemorragias ou fístulas. O teste de pressão reversa mostrou que o ducto cístico ocluído pelo bisturi harmônico suportou ao pelo menos 36 mmHg de pressão sem que ocorresse nenhum vazamento. CONCLUSÃO: O bisturi harmônico é eficaz e seguro em colecistectomias laparoscópicas eletivas como um instrumento único para ocluir e seccionar tanto a artéria cística quanto o ducto cístico. Vantagens podem ser apontadas ao método com relação a sua segurança e diminuição do tempo cirúrgico. .

A possible role of Drosophila CTCF in mitotic bookmarking and maintaining chromatin domains during the cell cycle

BACKGROUND: The CCCTC-binding factor (CTCF) is a highly conserved insulator protein that plays various roles in many cellular processes. CTCF is one of the main architecture proteins in higher eukaryotes, and in combination with other architecture proteins and regulators, also shapes the three-dimensional organization of a genome. Experiments show CTCF partially remains associated with chromatin during mitosis. However, the role of CTCF in the maintenance and propagation of genome architectures throughout the cell cycle remains elusive. RESULTS: We performed a comprehensive bioinformatics analysis on public datasets of Drosophila CTCF (dCTCF). We characterized dCTCF-binding sites according to their occupancy status during the cell cycle, and identified three classes: interphase-mitosis-common (IM), interphase-only (IO) and mitosis-only (MO) sites. Integrated function analysis showed dCTCF-binding sites of different classes might be involved in different biological processes, and IM sites were more conserved and more intensely bound. dCTCF-binding sites of the same class preferentially localized closer to each other, and were highly enriched at chromatin syntenic and topologically associating domains boundaries. CONCLUSIONS: Our results revealed different functions of dCTCF during the cell cycle and suggested that dCTCF might contribute to the establishment of the three-dimensional architecture of the Drosophila genome by maintaining local chromatin compartments throughout the whole cell cycle.