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1.
Eur J Radiol ; 144: 110015, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34742108

RESUMO

PURPOSE: To develop a deep-learning object detection model for automatic detection of brain metastases that simultaneously uses contrast-enhanced and non-enhanced images as inputs, and to compare its performance with that of a model that uses only contrast-enhanced images. METHOD: A total of 116 computed tomography (CT) scans of 116 patients with brain metastases were included in this study. They showed a total of 659 metastases, 428 of which were used for training and validation (mean size, 11.3 ± 9.9 mm) and 231 were used for testing (mean size, 9.0 ± 7.0 mm). Single-shot detector (SSD) models were constructed with a feature fusion module, and their results were compared per lesion at a confidence threshold of 50%. RESULTS: The sensitivity was 88.7% for the model that used both contrast-enhanced and non-enhanced CT images (the CE + NECT model) and 87.6% for the model that used only contrast-enhanced CT images (the CECT model). The positive predictive value (PPV) was 44.0% for the CE + NECT model and 37.2% for the CECT model. The number of false positives per patient was 9.9 for the CE + NECT model and 13.6 for the CECT model. The CE + NECT model had a significantly higher PPV (t test, p < 0.001), significantly fewer false positives (t test, p < 0.001), and a tendency to be more sensitive (t test, p = 0.14). CONCLUSIONS: The results indicate that the information on true contrast enhancement obtained by comparing the contrast-enhanced and non-enhanced images may prevent the detection of pseudolesions, suppress false positives, and improve the performance of deep-learning object detection models.

2.
Micromachines (Basel) ; 12(10)2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34683214

RESUMO

Human red blood cells (RBCs) are subjected to high viscous shear stress, especially during microcirculation, resulting in stable deformed shapes such as parachute or slipper shape. Those unique deformed RBC shapes, accompanied with axial or nonaxial migration, cannot be fully described according to traditional knowledge about lateral movement of deformable spherical particles. Although several experimental and numerical studies have investigated RBC behavior in microchannels with similar diameters as RBCs, the detailed mechanical characteristics of RBC lateral movement-in particular, regarding the relationship between stable deformed shapes, equilibrium radial RBC position, and membrane load-has not yet been fully described. Thus, we numerically investigated the behavior of single RBCs with radii of 4 µm in a circular microchannel with diameters of 15 µm. Flow was assumed to be almost inertialess. The problem was characterized by the capillary number, which is the ratio between fluid viscous force and membrane elastic force. The power (or energy dissipation) associated with membrane deformations was introduced to quantify the state of membrane loads. Simulations were performed with different capillary numbers, viscosity ratios of the internal to external fluids of RBCs, and initial RBC centroid positions. Our numerical results demonstrated that axial or nonaxial migration of RBC depended on the stable deformed RBC shapes, and the equilibrium radial position of the RBC centroid correlated well with energy expenditure associated with membrane deformations.

3.
Micromachines (Basel) ; 12(10)2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34683293

RESUMO

The continuous separation and filtration of particles immersed in fluid flows are important interests in various applications. Although the inertial focusing of particles suspended in a duct flow is promising in microfluidics, predicting the focusing positions depending on the parameters, such as the shape of the duct cross-section and the Reynolds number (Re) has not been achieved owing to the diversity of the inertial-focusing phenomena. In this study, we aimed to elucidate the variation of the inertial focusing depending on Re in rectangular duct flows. We performed a numerical simulation of the lift force exerted on a spherical particle flowing in a rectangular duct and determined the lift-force map within the duct cross-section over a wide range of Re. We estimated the particle trajectories based on the lift map and Stokes drag, and identified the particle-focusing points appeared in the cross-section. For an aspect ratio of the duct cross-section of 2, we found that the blockage ratio changes transition structure of particle focusing. For blockage ratios smaller than 0.3, particles focus near the centres of the long sides of the cross-section at low Re and near the centres of both the long and short sides at relatively higher Re. This transition is expressed as a subcritical pitchfork bifurcation. For blockage ratio larger than 0.3, another focusing pattern appears between these two focusing regimes, where particles are focused on the centres of the long sides and at intermediate positions near the corners. Thus, there are three regimes; the transition between adjacent regimes at lower Re is found to be expressed as a saddle-node bifurcation and the other transition as a supercritical pitchfork bifurcation.

5.
BMC Neurol ; 21(1): 396, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34641814

RESUMO

BACKGROUND: Both fragile X-associated tremor/ataxia syndrome (FXTAS) and late-onset neuronal intranuclear inclusion disease (NIID) show CGG/GGC trinucleotide repeat expansions. Differentiating these diseases are difficult because of the similarity in their clinical and radiological features. It is unclear that skin biopsy can distinguish NIID from FXTAS. We performed a skin biopsy in an FXTAS case with cognitive dysfunction and peripheral neuropathy without tremor, which was initially suspected to be NIID. CASE PRESENTATION: The patient underwent neurological assessment and examinations, including laboratory tests, electrophysiologic test, imaging, skin biopsy, and genetic test. A brain MRI showed hyperintensity lesions along the corticomedullary junction on diffusion-weighted imaging (DWI) in addition to middle cerebellar peduncle sign (MCP sign). We suspected NIID from the clinical picture and the radiological findings, and performed a skin biopsy. The skin biopsy specimen showed ubiquitin- and p62-positive intranuclear inclusions, suggesting NIID. However, a genetic analysis for NIID using repeat-primed polymerase chain reaction (RP-PCR) revealed no expansion detected in the Notch 2 N-terminal like C (NOTCH2NLC) gene. We then performed genetic analysis for FXTAS using RP-PCR, which revealed a repeat CGG/GGC expansion in the FMRP translational regulator 1 (FMR1) gene. The number of repeats was 83. We finally diagnosed the patient with FXTAS rather than NIID. CONCLUSIONS: For the differential diagnosis of FXTAS and NIID, a skin biopsy alone is insufficient; instead, genetic analysis, is essential. Further investigations in additional cases based on genetic analysis are needed to elucidate the clinical and pathological differences between FXTAS and NIID.


Assuntos
Corpos de Inclusão Intranuclear , Tremor , Ataxia , Biópsia , Proteína do X Frágil de Retardo Mental , Síndrome do Cromossomo X Frágil , Humanos , Doenças Neurodegenerativas
6.
J Nat Med ; 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34669108

RESUMO

Diterpenoid alkaloids, the main components of plants of the genera Aconitum, Delphinium, and Garrya, are a group of natural products with notable chemical properties and biological activities. Several C19-diterpenoid alkaloid components from Delphinium elatum cv. Pacific Giant, as well as their derivatives, exhibited cytotoxic activity against lung, prostate, cervical, and vincristine-resistant cervical cancer cell lines. In the current phytochemical investigation on the seeds of D. elatum cv. Pacific Giant, eleven new C19-diterpenoid alkaloids, elapaciline (1), meladine (2), melapacitine (3), iminoeladine (4), 19-oxopaciline (5), 19-oxopacinine (6), N-deethyldelpheline (7), N-deethylpacinine (8), N-deethyl-19-oxoeladine (9), N-deethyl-N-formyleladine (10), and N-deethyl-N-formyldelpheline (11), together with 15 known C19-diterpenoid alkaloids were isolated. Their structures were elucidated by extensive spectroscopic methods including NMR (1D and 2D), IR, and MS (HRMS). Three known diterpenoid alkaloids, 6-dehydrodelcorine (12), delelatine (23), and 6-dehydroeldelidine (24), were isolated for the first time from this plant. Six of the new C19-diterpenoid alkaloids (2, 4-7, and 11) and three of the known diterpenoid alkaloids (18, 23, and 24) were evaluated for cytotoxic activity against five human tumor cell lines.

8.
J Neuroimaging ; 2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34388855

RESUMO

BACKGROUND AND PURPOSE: To examine whether feature-fusion (FF) method improves single-shot detector's (SSD's) detection of small brain metastases on contrast-enhanced (CE) T1-weighted MRI. METHODS: The study included 234 MRI scans from 234 patients (64.3 years±12.0; 126 men). The ground-truth annotation was performed semiautomatically. SSDs with and without an FF module were developed and trained using 178 scans. The detection performance was evaluated at the SSDs' 50% confidence threshold using sensitivity, positive-predictive value (PPV), and the false-positive (FP) per scan with the remaining 56 scans. RESULTS: FF-SSD achieved an overall sensitivity of 86.0% (95% confidence interval [CI]: [83.0%, 85.6%]; 196/228) and 46.8% PPV (95% CI: [42.0%, 46.3%]; 196/434), with 4.3 FP (95% CI: [4.3, 4.9]). Lesions smaller than 3 mm had 45.8% sensitivity (95% CI: [36.1%, 45.5%]; 22/48) with 2.0 FP (95% CI: [1.9, 2.1]). Lesions measuring 3-6 mm had 92.3% sensitivity (95% CI: [86.5%, 92.0%]; 48/52) with 1.8 FP (95% CI: [1.7, 2.2]). Lesions larger than 6 mm had 98.4% sensitivity (95% CI: [97.8%, 99.4%]; 126/128) 0.5 FP (95% CI: [0.5, 0.8]) per scan. FF-SSD had a significantly higher sensitivity for lesions < 3 mm (p = 0.008, t = 3.53) than the baseline SSD, while the overall PPV was similar (p = 0.06, t = -2.16). A similar trend was observed even when the detector's confidence threshold was varied as low as 0.2, for which the FF-SSD's sensitivity was 91.2% and the FP was 9.5. CONCLUSIONS: The FF-SSD algorithm identified brain metastases on CE T1-weighted MRI with high accuracy.

9.
Intern Med ; 2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34393162

RESUMO

A 68-year-old woman developed systemic blisters while receiving treatment for nephrotic syndrome. As she also developed marked liver dysfunction and disseminated intravascular coagulation, she was admitted to our hospital. She was diagnosed with varicella zoster virus (VZV) infection. Treatment was administered in the intensive-care unit, but the patient died on day 24 post-admission after severe VZV infection. A post-mortem examination showed micro-abscesses and necrosis caused by varicella zoster infection in multiple organs, including the liver, kidneys, and gastrointestinal tract. Because VZV infection can become severe in immunocompromised patients, careful consideration is needed for the prevention and treatment of the viral infection.

10.
Neuroradiology ; 63(12): 1995-2004, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34114064

RESUMO

PURPOSE: To develop and investigate deep learning-based detectors for brain metastases detection on non-enhanced (NE) CT. METHODS: The study included 116 NECTs from 116 patients (81 men, age 66.5 ± 10.6 years) to train and test single-shot detector (SSD) models using 89 and 27 cases, respectively. The annotation was performed by three radiologists using bounding-boxes defined on contrast-enhanced CT (CECT) images. NECTs were coregistered and resliced to CECTs. The detection performance was evaluated at the SSD's 50% confidence threshold using sensitivity, positive-predictive value (PPV), and the false-positive rate per scan (FPR). For false negatives and true positives, binary logistic regression was used to examine the possible contributing factors. RESULTS: For lesions 6 mm or larger, the SSD achieved a sensitivity of 35.4% (95% confidence interval (CI): [32.3%, 33.5%]); 51/144) with an FPR of 14.9 (95% CI [12.4, 13.9]). The overall sensitivity was 23.8% (95% CI: [21.3%, 22.8%]; 55/231) and PPV was 19.1% (95% CI: [18.5%, 20.4%]; 98/ of 513), with an FPR of 15.4 (95% CI [12.9, 14.5]). Ninety-five percent of the lesions that SSD failed to detect were also undetectable to radiologists (168/176). Twenty-four percent of the lesions (13/50) detected by the SSD were undetectable to radiologists. Logistic regression analysis indicated that density, necrosis, and size contributed to the lesions' visibility for radiologists, while for the SSD, the surrounding edema also enhanced the detection performance. CONCLUSION: The SSD model we developed could detect brain metastases larger than 6 mm to some extent, a quarter of which were even retrospectively unrecognizable to radiologists.


Assuntos
Neoplasias Encefálicas , Idoso , Neoplasias Encefálicas/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X
12.
PLoS One ; 16(6): e0252514, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34061893

RESUMO

Most corals acquire symbiodiniacean symbionts from the surrounding environment to initiate symbiosis. The cell densities of Symbiodiniaceae in the environment are usually low, and mechanisms may exist by which new coral generations attract suitable endosymbionts. Phototaxis of suitable symbiodiniacean cells toward green fluorescence in corals has been proposed as one such mechanism. In the present study, we observed the phototaxis action wavelength of various strains of Symbiodiniaceae and the fluorescence spectra of aposymbiotic Acropora tenuis larvae at the time of endosymbiont uptake. The phototaxis patterns varied among the Symbiodiniaceae species and "native" endosymbionts-commonly found in Acropora juveniles present in natural environments; that is, Symbiodinium microadriaticum was attracted to blue light rather than to green light. Another native endosymbiont, Durusdinium trenchii, showed no phototaxis specific to any wavelength. Although the larvae exhibited green and broad orange fluorescence under blue-violet excitation light, the maximum green fluorescence peak did not coincide with that of the phototaxis action spectrum of S. microadriaticum. Rather, around the peak wavelength of larval green fluorescence, this native endosymbiont showed slightly negative phototaxis, suggesting that the green fluorescence of A. tenuis larvae may not play a role in the initial attraction of native endosymbionts. Conversely, broad blue larval fluorescence under UV-A excitation covered the maximum phototaxis action wavelength of S. microadriaticum. We also conducted infection tests using native endosymbionts and aposymbiotic larvae under red LED light that does not excite visible larval fluorescence. Almost all larvae failed to acquire S. microadriaticum cells, whereas D. trenchii cells were acquired by larvae even under red illumination. Thus, attraction mechanisms other than visible fluorescence might exist, at least in the case of D. trenchii. Our results suggest that further investigation and discussion, not limited to green fluorescence, would be required to elucidate the initial attraction mechanisms.


Assuntos
Alveolados/fisiologia , Antozoários/fisiologia , Fluorescência , Larva/fisiologia , Simbiose/fisiologia , Animais , Recifes de Corais , Dinoflagelados/fisiologia , Fototaxia/fisiologia , Raios Ultravioleta
13.
Mar Drugs ; 19(3)2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33799701

RESUMO

Many corals establish symbiosis with Symbiodiniaceae cells from surrounding environments, but very few Symbiodiniaceae cells exist in the water column. Given that the N-acetyl-d-glucosamine-binding lectin ActL attracts Symbiodiniaceae cells, we hypothesized that corals must attract Symbiodiniaceae cells using ActL to acquire them. Anti-ActL antibody inhibited acquisition of Symbiodiniaceae cells, and rearing seawater for juvenile Acropora tenuis contained ActL, suggesting that juvenile A. tenuis discharge ActL to attract these cells. Among eight Symbiodiniaceae cultured strains, ActL attracted NBRC102920 (Symbiodinium tridacnidorum) most strongly followed by CS-161 (Symbiodinium tridacnidorum), CCMP2556 (Durusdinium trenchii), and CCMP1633 (Breviolum sp.); however, it did not attract GTP-A6-Sy (Symbiodinium natans), CCMP421 (Effrenium voratum), FKM0207 (Fugacium sp.), and CS-156 (Fugacium sp.). Juvenile polyps of A. tenuis acquired limited Symbiodiniaceae cell strains, and the number of acquired Symbiodiniaceae cells in a polyp also differed from each other. The number of Symbiodiniaceae cells acquired by juvenile polyps of A. tenuis was correlated with the ActL chemotactic activity. Thus, ActL could be used to attract select Symbiodiniaceae cells and help Symbiodiniaceae cell acquisition in juvenile polyps of A. tenuis, facilitating establishment of symbiosis between A. tenuis and Symbiodiniaceae cells.


Assuntos
Acetilglucosamina/metabolismo , Antozoários/metabolismo , Dinoflagelados/metabolismo , Lectinas/metabolismo , Animais , Técnicas de Cultura de Células , Dinoflagelados/citologia , Simbiose
14.
Mol Phylogenet Evol ; 161: 107158, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33753192

RESUMO

Dinoflagellates in the family Symbiodiniaceae are intensively investigated as algal symbionts of corals and other invertebrates, underpinning coral reef ecosystems as primary producers. Diversity, including regional diversification, of free-living communities is less studied. In this study, an environmental Symbiodiniaceae community at an isolated island, Okinotori Island, Japan, was investigated to determine whether the community is endemic or common with other locations near continents and major ocean currents. Symbiotic algae in common corals at the island were the same type as those of the corals from other Japanese waters. In the environmental samples, genera Symbiodinium (formerly clade A), Cladocopium (clade C), Durusdinium (clade D), and clades F (including Freudenthalidium), G, and I, were identified through analysis of internal transcribed spacer region 2 of nuclear ribosomal RNA gene (ITS2) sequences. Interestingly, some sequences found were genetically different from those of previously reported genera/clades. These unknown sequences were genetically included in the Symbiodiniaceae linage, but they were differentiated from the previously known nine clades. The sequences formed a cluster in the phylogenetic tree based on 28S nrDNA. These sequences were thus considered members of a novel clade in the family (clade J). In total, 120 kinds of ITS2 sequences were produced; while 10 were identical to previously reported sequences, the majority were highly divergent. These genetically unique Symbiodiniaceae types, including novel clade J, may have evolved in isolation and reflect the environmental characteristics of the Okinotori Island.


Assuntos
Biodiversidade , Recifes de Corais , Dinoflagelados/genética , Dinoflagelados/isolamento & purificação , Ilhas , Animais , Antozoários , Dinoflagelados/classificação , Oceano Pacífico , Filogenia , Simbiose
15.
Eur J Radiol ; 136: 109577, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33550213

RESUMO

PURPOSE: Despite the potential usefulness, no automatic detector is available for brain metastases on contrast-enhanced CT (CECT). The study aims to develop and investigate deep learning-based detectors for brain metastases detection on CECT. METHOD: The study included 127 CECTs from 127 patients (65.5 years±11.1; 87 men). The ground-truth annotation was performed semi-automatically by applying connected-component analysis to the binarized dataset by three radiologists. Single-shot detector (SSD) algorithms, with and without a feature-fusion module, were developed and trained using 97 scans. The performance was evaluated at the detector's 50 % confidence threshold with the remaining 30 scans using sensitivity, positive-predictive value (PPV), and the false-positive rate per scan (FPR). RESULTS: Feature-fused SSD achieved an overall sensitivity of 88.1 % (95 % confidence interval [CI]: [85.2 %,88.6 %]; 214/243) and PPV of 36.0 % (95 % CI: [33.7 %,37.1 %]; 233/648), with 13.8 FPR (95 % CI: [12.7,15.0]). Lesions < 3 mm had a sensitivity of 23.1 % (95 % CI: [21.2 %,40.0 %]; 3/13), with 0.2 FPR (95 % CI: [0.23,0.65]). Lesions measuring 3-6 mm had a sensitivity of 80.0 % (95 % CI: [76.0 %,79.8 %]); 60/75) with 5.8 FPR (95 % CI: [5.0,6.2]). Lesions > 6 mm had a sensitivity of 97.4 % (95 % CI: [94.1 %,97.4 %]); 151/155) with 7.9 FPR (95 % CI: [7.2,8.5]). Feature-fused SSD had a significantly higher overall sensitivity (p = 0.03, t = 2.75) or sensitivity for lesions < 3 mm (p = 0.002, t = 4.49) than baseline SSD, while the overall PPV was similar (p = 0.96, t = -0.02). CONCLUSIONS: The SSD algorithm identified brain metastases on CECT with reasonable accuracy for lesions > 3 mm without pre/post-processing.


Assuntos
Neoplasias Encefálicas , Aprendizado Profundo , Algoritmos , Neoplasias Encefálicas/diagnóstico por imagem , Humanos , Masculino , Tomografia Computadorizada por Raios X
16.
Heliyon ; 7(2): e06196, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33615009

RESUMO

A 39-year-old man with type 1 diabetes, who had a 4-year history of Graves' disease being treated with propylthiouracil (PTU), had developed sudden hearing loss. However, he showed no other clinical manifestations. Intratympanic administration with dexamethasone had failed, and his hearing had deteriorated. Magnetic resonance imaging showed the contrast effect on T1-weighted image in both cochleae, and the serum immunological analysis showed the high titers for anti-neutrophil cytoplasmic antibodies (ANCA). Therefore, his sudden hearing loss was presumed to be initial presentation of ANCA-associated vasculitis owing to PTU. His hearing was rapidly restored by a PTU withdrawal while no use of immunosuppressive agents, and he confirmed his hearing improvement in ordinary conversation. The patient's clinical course suggests that bilateral sensorineural hearing loss that occurs during treating hyperthyroidism could be initial presentation of ANCA-associated vasculitis, and discontinuing anti-thyroid drugs should be considered before treating with glucocorticoids.

17.
Genome Biol Evol ; 13(1)2021 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-33185681

RESUMO

Reef-building corals and photosynthetic, endosymbiotic algae of the family Symbiodiniaceae establish mutualistic relationships that are fundamental to coral biology, enabling coral reefs to support a vast diversity of marine species. Although numerous types of Symbiodiniaceae occur in coral reef environments, Acropora corals select specific types in early life stages. In order to study molecular mechanisms of coral-algal symbioses occurring in nature, we performed whole-genome transcriptomic analyses of Acropora tenuis larvae inoculated with Symbiodinium microadriaticum strains isolated from an Acropora recruit. In order to identify genes specifically involved in symbioses with native symbionts in early life stages, we also investigated transcriptomic responses of Acropora larvae exposed to closely related, nonsymbiotic, and occasionally symbiotic Symbiodinium strains. We found that the number of differentially expressed genes was largest when larvae acquired native symbionts. Repertoires of differentially expressed genes indicated that corals reduced amino acid, sugar, and lipid metabolism, such that metabolic enzymes performing these functions were derived primarily from S. microadriaticum rather than from A. tenuis. Upregulated gene expression of transporters for those metabolites occurred only when coral larvae acquired their natural symbionts, suggesting active utilization of native symbionts by host corals. We also discovered that in Acropora, genes for sugar and amino acid transporters, prosaposin-like, and Notch ligand-like, were upregulated only in response to native symbionts, and included tandemly duplicated genes. Gene duplications in coral genomes may have been essential to establish genomic novelties for coral-algae symbiosis.

18.
Mol Biol Evol ; 38(1): 16-30, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-32877528

RESUMO

The genus Acropora comprises the most diverse and abundant scleractinian corals (Anthozoa, Cnidaria) in coral reefs, the most diverse marine ecosystems on Earth. However, the genetic basis for the success and wide distribution of Acropora are unknown. Here, we sequenced complete genomes of 15 Acropora species and 3 other acroporid taxa belonging to the genera Montipora and Astreopora to examine genomic novelties that explain their evolutionary success. We successfully obtained reasonable draft genomes of all 18 species. Molecular dating indicates that the Acropora ancestor survived warm periods without sea ice from the mid or late Cretaceous to the Early Eocene and that diversification of Acropora may have been enhanced by subsequent cooling periods. In general, the scleractinian gene repertoire is highly conserved; however, coral- or cnidarian-specific possible stress response genes are tandemly duplicated in Acropora. Enzymes that cleave dimethlysulfonioproprionate into dimethyl sulfide, which promotes cloud formation and combats greenhouse gasses, are the most duplicated genes in the Acropora ancestor. These may have been acquired by horizontal gene transfer from algal symbionts belonging to the family Symbiodiniaceae, or from coccolithophores, suggesting that although functions of this enzyme in Acropora are unclear, Acropora may have survived warmer marine environments in the past by enhancing cloud formation. In addition, possible antimicrobial peptides and symbiosis-related genes are under positive selection in Acropora, perhaps enabling adaptation to diverse environments. Our results suggest unique Acropora adaptations to ancient, warm marine environments and provide insights into its capacity to adjust to rising seawater temperatures.


Assuntos
Adaptação Biológica , Antozoários/genética , Evolução Biológica , Mudança Climática , Fósseis , Animais , Genoma
19.
J Obstet Gynaecol ; 41(4): 557-561, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32729350

RESUMO

The aim of this study was to compare the benefits and hemodynamic side effects of oxytocin between intravenous infusion with and without a bolus injection during a caesarean section. Women with singleton pregnancies who underwent caesarean sections under spinal anaesthesia were included. Oxytocin was administered by an iv bolus injection (5 U) followed by an intravenous infusion (10 U of oxytocin in 500 mL normal saline); this was switched to just an intravenous infusion. The amount of blood loss did not differ between the groups. In a multivariate analysis, the adjusted odds ratios for the risk of hypotension (≥20% reduction of systolic BP) and tachycardia (heart rate ≥100 bpm) were 4.5 (95% confidence interval [CI], 1.6-12.5) and 3.7 (95%CI 1.9-7.2) in the iv bolus group, respectively, compared with the just the infusion group. The oxytocin administration by iv bolus injection did not decrease blood loss and increased the rate of hemodynamic side effects.Impact statementWhat is already known on this subject? Oxytocin is used as the first-line uterotonic treatment to prevent a postpartum haemorrhage in women undergoing Caesarean Sections. Oxytocin is known to relax vascular smooth muscle, which can cause hypotension and tachycardia. The protocols for administering oxytocin during CS vary by institution.What do the results of this study add? Combined treatment with oxytocin by iv bolus injection (5 U) followed by iv infusion (10 U of oxytocin in 500 mL normal saline) during CS increased the risk of developing adverse hemodynamic side effects, including hypotension, tachycardia, and the need for vasopressors, without any benefit in the control of intraoperative blood loss in comparison to iv infusion alone.What are the implications of these findings for clinical practice and/or further research? We should abandon the iv bolus injection of oxytocin during CS, especially for women undergoing an elective CS who are not in labour.

20.
PLoS One ; 15(12): e0243087, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33326418

RESUMO

Because more than 80% of species of gamete-spawning corals, including most Acroporidae species, do not inherit Symbiodiniaceae from their parents, they must acquire symbiont cells from sources in their environment. To determine whether photosynthetically competent Symbiodiniaceae expelled as fecal pellets from giant clams are capable of colonizing corals, we conducted laboratory experiments in which planula larvae of Acropora tenuis were inoculated with the cells in fecal pellets obtained from Tridacna crocea. T. crocea fecal pellets were administered once a day, and three days later, cells of Symbiodiniaceae from the fecal pellets had been taken up by the coral larvae. T. crocea fecal pellets were not supplied from the 4th day until the 8th day, and the cell densities in the larvae increased until the 8th day, which indicated the successful colonization by Symbiodiniaceae. The control group exhibited the highest mean percentage of larvae (100%) that were successfully colonized by culture strains of Symbiodiniaceae, and larvae inoculated with fecal pellets reached a colonization percentage of 66.7 ~ 96.7% on the 8th day. The highest colonization rate was achieved with the fecal pellets containing cells with high photosynthetic competency (Fv/Fm). Interestingly, the genetic composition of Symbiodiniaceae in the larvae retrieved on the 8th day differed from that in the fecal pellets and showed exclusive domination of the genus Symbiodinium. A minor but significant population of the genus Cladocopium in the fecal pellets was not inherited by the larvae. These experiments provided the first demonstration that the Symbiodiniaceae from tridacnine clams provided via fecal pellets can colonize and even proliferate in coral larvae.


Assuntos
Alveolados/isolamento & purificação , Antozoários/parasitologia , Bivalves/parasitologia , Alveolados/classificação , Alveolados/genética , Animais , Recifes de Corais , DNA de Protozoário/genética , Fezes/parasitologia , Fotossíntese , Análise de Sequência de DNA , Simbiose
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