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1.
Rev Esp Enferm Dig ; 112(6): 511-512, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32496123

RESUMO

We have read with interest the article published by Pérez et al., we really appreciate their interesting comments and would like to qualify some points. With the except of the clinical practice, currently there is no recommendation based on scientific evidence about the use of apheresis in the treatment of ulcerative colitis (UC), and even less in Crohn's disease (CD). However, the results obtained in the case of Pérez et al. in relation to systemic inflammation and pulmonary clinical improvement are very interesting from a pathophysiological and clinical point of view.


Assuntos
Colite Ulcerativa , Vírus da SARS , Betacoronavirus , Infecções por Coronavirus , Sistema Digestório , Humanos , Pandemias , Pneumonia Viral
2.
Rev Esp Enferm Dig ; 112(6): 511, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32496122

RESUMO

Crespo et al. comment on the influence of immunomodulators and biological drugs on ulcerative colitis and SARS-CoV-2 infection. Granulo-monocytoapheresis is a treatment used in ulcerative colitis outbreaks, whose mechanism of action is to selectively retain activated granulocytes and monocytes, in order to reduce the inflammatory process.


Assuntos
Colite Ulcerativa , Vírus da SARS , Betacoronavirus , Infecções por Coronavirus , Sistema Digestório , Humanos , Leucaférese , Pandemias , Pneumonia Viral
3.
Rev Bras Parasitol Vet ; 29(2): e002220, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32428186

RESUMO

This study aimed to evaluate the effects of Trichostrongylus colubriformis infection on the hemato-biochemical parameters, feed digestibility, and nitrogen balance in Santa Inês lambs. Eighteen three-month-old Santa Ines castrated male lambs (16.9 ± 1.43 kg of body weight) were randomly distributed in two experimental treatments: infected with T. colubriformis (I, n = 9) and uninfected (U, n = 9). The I group received a total of 45,000 L3 larvae of T. colubriformis (5,000 infective larvae, three times per week, for three weeks). During the experimental period, blood, feed digestibility, and nitrogen balance were evaluated. The I lambs showed a reduction in erythrocytes, hemoglobin, hematocrit, mean corpuscular volume, and total proteins, as well as an increase in platelets and eosinophils compared to those in the U group (p < 0.05). With the exception of total protein content, these values were within the normal range for the species. Furthermore, lower dry matter and organic matter digestibility were observed in the I lambs (p = 0.08). The present findings highlight that T. colubriformis infection has the potential to impair some hemato-biochemical parameters as well as feed digestibility in lambs, which could affect their productivity.


Assuntos
Proteínas Sanguíneas/análise , Sistema Digestório/parasitologia , Nitrogênio/análise , Ovinos/parasitologia , Tricostrongilose/parasitologia , Trichostrongylus/parasitologia , Ácido 3-Hidroxibutírico/sangue , Animais , Contagem de Células Sanguíneas/veterinária , Modelos Animais de Doenças , Índices de Eritrócitos/veterinária , Fezes/química , Fezes/parasitologia , Hemoglobinas/análise , Masculino , Nitrogênio/urina , Soroalbumina Bovina/análise , Soroglobulinas/análise , Doenças dos Ovinos/parasitologia , Tricostrongilose/sangue , Tricostrongilose/urina , Tricostrongilose/veterinária
4.
Pol Arch Intern Med ; 130(5): 420-430, 2020 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-32356641

RESUMO

The outbreak of the coronavirus disease 2019 (COVID­19) pandemic has become the biggest challenge for the whole human community since many years. It seems that the proper identification of all people infected with severe acute respiratory syndrome coronavirus 2 (SARS­CoV­2) is the best strategy to limit the transmission. However, in a significant proportion of patients, there are no clinical manifestations of the disease, and symptoms may be very mild or atypical. There is a growing body of evidence that digestive manifestations of COVID­19 are frequently reported and may precede typical respiratory symptoms. Moreover, SARS­CoV­2 particles were found in the gastrointestinal epithelial cells, and viral RNA was detected in the feces of patients with COVID­19. These data suggest that gastrointestinal symptoms in COVID­19 are not accidental findings and they may result from direct digestive involvement. Patients with new­onset diarrhea, abdominal pain, nausea, and vomiting without any other evident etiological factors should be tested for SARS­CoV­2 infection. Gastroenterologists and members of other medical specialties should also remember that the current epidemiological situation has changed diagnostic and therapeutic algorithms in the management of several gastrointestinal and liver disorders. This review article summarizes the currently available data on multiple gastroenterological aspects of COVID­19 and provides information on practical recommendations and position statements of the most prominent associations in the field of gastroenterology, which appeared in response to the emergence of the pandemic.


Assuntos
Betacoronavirus/metabolismo , Infecções por Coronavirus/complicações , Doenças do Sistema Digestório/virologia , Sistema Digestório/virologia , Pneumonia Viral/complicações , Coronavirus/metabolismo , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/terapia , Sistema Digestório/metabolismo , Humanos , Pandemias , Pneumonia Viral/diagnóstico , Pneumonia Viral/terapia
5.
Biomed Pharmacother ; 127: 110195, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32361161

RESUMO

Since early December 2019, a number of pneumonia cases associated with unknown coronavirus infection were identified in Wuhan, China, and many additional cases were identified in other regions of China and in other countries within 3 months. Currently, more than 80,000 cases have been diagnosed in China, including more than 3000 deaths. The epidemic is spreading to the rest of the world, posing a grave challenge to prevention and control. On February 12, 2020, the International Committee on Taxonomy of Viruses and the World Health Organization officially named the novel coronavirus and associated pneumonia as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and coronavirus disease 2019 (COVID-19), respectively. According to the recent research on SARS-CoV-2, the virus mainly infects the respiratory system but may cause damage to other systems. In this paper, we will systematically review the pathogenic features, transmission routes, and infection mechanisms of SARS-CoV-2, as well as any adverse effects on the digestive system, urogenital system, central nervous system, and circulatory system, in order to provide a theoretical and clinical basis for the diagnosis, classification, treatment, and prognosis assessment of SARS-CoV-2 infection.


Assuntos
Betacoronavirus , Sistema Cardiovascular/virologia , Sistema Nervoso Central/virologia , Infecções por Coronavirus , Sistema Digestório/virologia , Insuficiência de Múltiplos Órgãos , Pandemias , Pneumonia Viral , Sistema Urogenital/virologia , Betacoronavirus/isolamento & purificação , Betacoronavirus/patogenicidade , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/fisiopatologia , Infecções por Coronavirus/terapia , Infecções por Coronavirus/transmissão , Gerenciamento Clínico , Humanos , Insuficiência de Múltiplos Órgãos/prevenção & controle , Insuficiência de Múltiplos Órgãos/virologia , Pneumonia Viral/epidemiologia , Pneumonia Viral/fisiopatologia , Pneumonia Viral/terapia , Pneumonia Viral/transmissão
6.
Infect Dis Poverty ; 9(1): 45, 2020 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-32345362

RESUMO

BACKGROUND: Since its discovery in December 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected more than 2 180 000 people worldwide and has caused more than 150 000 deaths as of April 16, 2020. SARS-CoV-2, which is the virus causing coronavirus disease 2019 (COVID-19), uses the angiotensin-converting enzyme 2 (ACE2) as a cell receptor to invade human cells. Thus, ACE2 is the key to understanding the mechanism of SARS-CoV-2 infection. This study is to investigate the ACE2 expression in various human tissues in order to provide insights into the mechanism of SARS-CoV-2 infection. METHODS: We compared ACE2 expression levels across 31 normal human tissues between males and females and between younger (ages ≤ 49 years) and older (ages > 49 years) persons using two-sided Student's t test. We also investigated the correlations between ACE2 expression and immune signatures in various tissues using Pearson's correlation test. RESULTS: ACE2 expression levels were the highest in the small intestine, testis, kidneys, heart, thyroid, and adipose tissue, and were the lowest in the blood, spleen, bone marrow, brain, blood vessels, and muscle. ACE2 showed medium expression levels in the lungs, colon, liver, bladder, and adrenal gland. ACE2 was not differentially expressed between males and females or between younger and older persons in any tissue. In the skin, digestive system, brain, and blood vessels, ACE2 expression levels were positively associated with immune signatures in both males and females. In the thyroid and lungs, ACE2 expression levels were positively and negatively associated with immune signatures in males and females, respectively, and in the lungs they had a positive and a negative correlation in the older and younger groups, respectively. CONCLUSIONS: Our data indicate that SARS-CoV-2 may infect other tissues aside from the lungs and infect persons with different sexes, ages, and races equally. The different host immune responses to SARS-CoV-2 infection may partially explain why males and females, young and old persons infected with this virus have markedly distinct disease severity. This study provides new insights into the role of ACE2 in the SARS-CoV-2 pandemic.


Assuntos
Betacoronavirus , Peptidil Dipeptidase A/genética , Receptores Virais/genética , Adulto , Fatores Etários , Idoso , Encéfalo/enzimologia , Sistema Cardiovascular/enzimologia , Sistema Cardiovascular/imunologia , Sistema Digestório/enzimologia , Sistema Digestório/imunologia , Glândulas Endócrinas/enzimologia , Glândulas Endócrinas/imunologia , Feminino , Perfilação da Expressão Gênica , Humanos , Sistema Imunitário/enzimologia , Interferons/imunologia , Pulmão/enzimologia , Pulmão/imunologia , Linfócitos/imunologia , Masculino , Pessoa de Meia-Idade , Especificidade de Órgãos , Peptidil Dipeptidase A/sangue , RNA-Seq , Receptores Virais/sangue , Fatores Sexuais , Sistema Urogenital/enzimologia
7.
Rev Esp Enferm Dig ; 112(5): 389-396, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32338017

RESUMO

The purpose of this rapid review is to provide an update on the impact of SARS-CoV-2 infection on Gastroenterology and Hepatology departments, our patients, and our new way of working. The gastrointestinal tract and the liver are affected by SARS-CoV-2, especially in patients with immunosuppressive therapies. Patients with liver transplantation should be followed closely. Digestive endoscopy is a high-risk procedure for the transmission of SARS-CoV-2. While the pandemic lasts, we must adapt its indications and promote protective measures for patients and healthcare professionals alike. The COVID-19 pandemic has changed our priorities and the way we work, although we do not know what the repercussions will be after normality is reinstated.


Assuntos
Betacoronavirus/patogenicidade , Infecções por Coronavirus/transmissão , Doenças do Sistema Digestório/virologia , Sistema Digestório/virologia , Pandemias , Pneumonia Viral/transmissão , Infecções por Coronavirus/virologia , Doenças do Sistema Digestório/diagnóstico , Doenças do Sistema Digestório/terapia , Transmissão de Doença Infecciosa/prevenção & controle , Endoscopia do Sistema Digestório/efeitos adversos , Humanos , Imunossupressores/efeitos adversos , Controle de Infecções/métodos , Transplante de Fígado , Pneumonia Viral/virologia
8.
Chemosphere ; 251: 126438, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32169693

RESUMO

Bombyx mori is an important economic insect. However, the environmental pollution caused by the widespread use of neonicotinoid insecticides has significantly affected the safe production of sericulture. In this paper, we determined the LC50 of acetamiprid, a kind of neonicotinoid insecticides, to 5th instar silkworm larvae, examined its residues in hemolymph and midgut of silkworm after continuous exposure to low-dose of acetamiprid, and investigated the transcription level of detoxifying-related genes and the activity of detoxifying enzymes. The results showed that acetamiprid was highly toxic (24-h LC50, 1.50 mg/L) to silkworm larvae. After continuous exposure to low-dose of acetamiprid (0.15 mg/L), the acetamiprid residue concentrations in hemolymph and midgut were 0.90 and 0.58 µg/mg, respectively, at 48 h, but all decreased at 96 h. At 24 h of acetamiprid exposure, the transcription levels of CYP4M5 and CYP6AB4 and the P450 enzyme activity were significantly enhanced. However, the transcription levels of CarE and CarE-11 and the activity of CarE enzymes were both inhibited by acetamiprid exposure. After 24 h-72 h of acetamiprid exposure, the transcription levels of GSTe3 and GSTd1 were significantly up-regulated, and the GST enzyme activity was also significantly elevated from 48 h to 96 h. Furthermore, the expression levels of FoxO, CncC and Keap1, the key upstream genes of detoxification enzymes, showed a similar trend as the GST genes. These results indicated that acetamiprid was reduced in midgut and the expression of GSTs was upregulated may via FoxO/CncC/Keap1 signaling pathway, which plays a key role in detoxification responses.


Assuntos
Bombyx/fisiologia , Inseticidas/toxicidade , Neonicotinoides/toxicidade , Animais , Bombyx/enzimologia , Bombyx/metabolismo , Sistema Digestório/metabolismo , Inativação Metabólica , Proteína 1 Associada a ECH Semelhante a Kelch , Larva/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Transdução de Sinais
9.
J Gastroenterol Hepatol ; 35(5): 744-748, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32215956

RESUMO

The novel coronavirus disease is currently causing a major pandemic. It is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a member of the Betacoronavirus genus that also includes the SARS-CoV and Middle East respiratory syndrome coronavirus. While patients typically present with fever and a respiratory illness, some patients also report gastrointestinal symptoms such as diarrhea, vomiting, and abdominal pain. Studies have identified the SARS-CoV-2 RNA in stool specimens of infected patients, and its viral receptor angiotensin converting enzyme 2 was found to be highly expressed in gastrointestinal epithelial cells. These suggest that SARS-CoV-2 can actively infect and replicate in the gastrointestinal tract. This has important implications to the disease management, transmission, and infection control. In this article, we review the important gastrointestinal aspects of the disease.


Assuntos
Betacoronavirus/isolamento & purificação , Infecções por Coronavirus , Doenças do Sistema Digestório/virologia , Sistema Digestório/virologia , Pandemias , Peptidil Dipeptidase A/biossíntese , Pneumonia Viral , Aerossóis/efeitos adversos , Betacoronavirus/metabolismo , Infecções por Coronavirus/complicações , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/metabolismo , Infecções por Coronavirus/transmissão , Sistema Digestório/citologia , Sistema Digestório/metabolismo , Doenças do Sistema Digestório/metabolismo , Transmissão de Doença Infecciosa/prevenção & controle , Humanos , Controle de Infecções/métodos , Pneumonia Viral/complicações , Pneumonia Viral/diagnóstico , Pneumonia Viral/metabolismo , Pneumonia Viral/transmissão , RNA Viral/isolamento & purificação
10.
PLoS One ; 15(3): e0229537, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32130257

RESUMO

Microbes alter their transcriptomic profiles in response to the environment. The physiological conditions experienced by a microbial community can thus be inferred using meta-transcriptomic sequencing by comparing transcription levels of specifically chosen genes. However, this analysis requires accurate reference genomes to identify the specific genes from which RNA reads originate. In addition, such an analysis should avoid biases in transcript counts related to differences in organism abundance. In this study we describe an approach to address these difficulties. Sample-specific meta-genomic assembled genomes (MAGs) were used as reference genomes to accurately identify the origin of RNA reads, and transcript ratios of genes with opposite transcription responses were compared to eliminate biases related to differences in organismal abundance, an approach hereafter named the "diametric ratio" method. We used this approach to probe the environmental conditions experienced by Escherichia spp. in the gut of 4 premature infants, 2 of whom developed necrotizing enterocolitis (NEC), a severe inflammatory intestinal disease. We analyzed twenty fecal samples taken from four premature infants (4-6 time points from each infant), and found significantly higher diametric ratios of genes associated with low oxygen levels in samples of infants later diagnosed with NEC than in samples without NEC. We also show this method can be used for examining other physiological conditions, such as exposure to nitric oxide and osmotic pressure. These study results should be treated with caution, due to the presence of confounding factors that might also distinguish between NEC and control infants. Nevertheless, together with benchmarking analyses, we show here that the diametric ratio approach can be applied for evaluating the physiological conditions experienced by microbes in situ. Results from similar studies can be further applied for designing diagnostic methods to detect NEC in its early developmental stages.


Assuntos
Microbioma Gastrointestinal/genética , Microbioma Gastrointestinal/fisiologia , Recém-Nascido Prematuro/fisiologia , Estudos de Casos e Controles , Bases de Dados Genéticas , Sistema Digestório/microbiologia , Fenômenos Fisiológicos do Sistema Digestório , Complexo IV da Cadeia de Transporte de Elétrons/genética , Enterocolite Necrosante/diagnóstico , Enterocolite Necrosante/genética , Enterocolite Necrosante/microbiologia , Escherichia/genética , Escherichia/isolamento & purificação , Feminino , Genes Bacterianos , Humanos , Recém-Nascido , Masculino , Metagenoma , Microbiota/genética , Transcriptoma
11.
Can Assoc Radiol J ; 71(2): 231-237, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32062986

RESUMO

PURPOSE: This study aims to evaluate the overall diagnostic accuracy of preoperative multidetector computed tomography (MDCT) in penetrating abdominal and pelvic injuries (PAPI). METHOD AND MATERIALS: We used our hospitals' trauma registry to retrospectively identify patients with PAPI from January 1, 2006, to December 31, 2016. Only patients who had a 64-MDCT scan at presentation and subsequently underwent laparotomy or laparoscopy were included in our study cohort. Each finding noted on MDCT was rated using a 5-point scale to indicate certainty of injury, with a score of 0 being definitive. Using surgical findings as the gold standard, the accuracy of radiology reports was analyzed in 2 ways. A κ statistic was calculated to evaluate each pair of values for absolute agreement, and ratings for all organ systems were analyzed using a repeated measures analysis of variance (ANOVA) to determine whether radiology and surgical findings were similar enough to be clinically meaningful. Qualitative review of the radiology and surgical reports focused on the gastrointestinal (GI) tract was conducted. RESULTS: Our cohort consisted of 38 males and 4 females with a median age of 29 years and a median injury severity score of 15.6. For this study, 12 different organ groups were categorized and analyzed. Of those organ groups, absolute agreement between MDCT and surgical findings was found only for liver and spleen (κ values ranging from 0.2 to 0.5). Additionally, the ANOVA revealed an interaction between finding type and organ system (F 1, 33 = 7.4, P < .001). The most clinically significant discrepancies between MDCT and surgical findings were for gallbladder, bowel, mesenteric, and diaphragmatic injuries. Qualitative review of the GI tract revealed that radiologists can detect significant findings such as presence of injury, however, localization and extent of injury pose a challenge. CONCLUSION: The detection of clinically significant injuries to solid organs in trauma patients with PAPI on 64-MDCT is adequate. However, detection of injury to the remaining organ groups on MDCT, especially bowel, mesentery, and diaphragm, remains a challenge.


Assuntos
Traumatismos Abdominais/diagnóstico por imagem , Sistema Digestório/diagnóstico por imagem , Sistema Digestório/lesões , Tomografia Computadorizada Multidetectores , Pelve/lesões , Ferimentos Penetrantes/diagnóstico por imagem , Traumatismos Abdominais/cirurgia , Adolescente , Adulto , Idoso , Diafragma/diagnóstico por imagem , Diafragma/lesões , Feminino , Vesícula Biliar/diagnóstico por imagem , Vesícula Biliar/lesões , Humanos , Escala de Gravidade do Ferimento , Intestinos/diagnóstico por imagem , Intestinos/lesões , Fígado/diagnóstico por imagem , Fígado/lesões , Masculino , Mesentério/diagnóstico por imagem , Mesentério/lesões , Pessoa de Meia-Idade , Pelve/diagnóstico por imagem , Pelve/cirurgia , Período Pré-Operatório , Estudos Retrospectivos , Sensibilidade e Especificidade , Baço/diagnóstico por imagem , Baço/lesões , Ferimentos Penetrantes/cirurgia , Adulto Jovem
12.
Chemosphere ; 248: 126075, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32028166

RESUMO

The honeybee, Apis mellifera is economically important for its products (honey, wax, and propolis) and for its role in pollination. This insect is threated due to high population losses in both agriculture and beekeeping. Within causes involved in the loss of honeybees is the increased pesticide use on agriculture. Although current testing for the regularization of insecticide use considers its acute toxic effects on pollinators, little is known about the effects of chronic exposure to sublethal concentrations that may persist in the environment. This study investigated the effect of chronic exposure to sublethal concentrations of lambda-cyhalothrin on the midgut, hypopharyngeal glands, and brain of A. mellifera. Honey bees were fed for eight days with LC50/100 insecticide. Subsequently, the midgut, hypopharyngeal glands, and brain were analyzed in light and transmission electron microscopies. The midgut was not affected after exposure, except in the posterior region with cell fragments in the lumen and changes in the mitochondria. The hypopharyngeal glands were severely affected by the insecticide with changes in the rough endoplasmic reticulum and cell death. The brain has extensive gaps in the neuropil as well as in the cellular bodies, especially in the corpora pedunculata. These resembled cellular alterations similar to those seen in death processes. The results of this study indicate that lambda-cyhalothrin is toxic to bees at sublethal concentrations and ingested chronically, causing damage to the midgut, hypopharyngeal glands, and brain, and may affect physiological and behavioral aspects of these insects.


Assuntos
Abelhas/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Sistema Digestório/efeitos dos fármacos , Hipofaringe/efeitos dos fármacos , Inseticidas/toxicidade , Nitrilos/toxicidade , Piretrinas/toxicidade , Animais , Encéfalo/ultraestrutura , Sistema Digestório/ultraestrutura , Hipofaringe/ultraestrutura , Dose Letal Mediana , Microscopia Eletrônica de Transmissão , Polinização/efeitos dos fármacos
13.
PLoS Negl Trop Dis ; 14(2): e0007948, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32012156

RESUMO

Aedes cadherin (AaeCad, AAEL024535) has been characterized as a receptor for Bacillus thuringiensis subsp. israelensis (Bti) Cry11A toxins. However, its role in development is still unknown. In this study, we modified the cadherin gene using ZFN and TALEN. Even though we obtained heterozygous deletions, no homozygous mutants were viable. Because ZFN and TALEN have lower off-targets than CRISPR/Cas9, we conclude the cadherin gene is essential for Aedes development. In contrast, in lepidopteran insects loss of a homologous cadherin does not appear to be lethal, since homozygous mutants are viable. To analyze the role of AaeCad in vivo, we tagged this protein with EGFP using CRISPR-Cas9-mediated homologous recombination and obtained a homozygous AaeCad-EGFP line. Addition of Aedes Rad51 mRNA enhanced the rate of recombination. We then examined AaeCad protein expression in most tissues and protein dynamics during mosquito development. We observe that AaeCad is expressed in larval and adult midgut-specific manner and its expression pattern changed during the mosquito development. Confocal images showed AaeCad has high expression in larval caecae and posterior midgut, and also in adult midgut. Expression of AaeCad is observed primarily in the apical membranes of epithelial cells, and not in cell-cell junctions. The expression pattern observed suggests AaeCad does not appear to play a role in these junctions. However, we cannot exclude its role beyond cell-cell adhesion in the midgut. We also observed that Cry11A bound to the apical side of larval gastric caecae and posterior midgut cells exactly where AaeCad-EGFP was expressed. Their co-localization suggests that AaeCad is indeed a receptor for the Cry11A toxin. Using this mosquito line we also observed that low doses of Cry11A toxin caused the cells to slough off membranes, which likely represents a defense mechanism, to limit cell damage from Cry11A toxin pores formed in the cell membrane.


Assuntos
Aedes/metabolismo , Proteínas de Bactérias/metabolismo , Endotoxinas/metabolismo , Proteínas Hemolisinas/metabolismo , Proteínas de Insetos/metabolismo , Larva/crescimento & desenvolvimento , Aedes/genética , Aedes/crescimento & desenvolvimento , Animais , Proteínas de Bactérias/genética , Caderinas/metabolismo , Sistema Digestório/crescimento & desenvolvimento , Sistema Digestório/metabolismo , Endotoxinas/genética , Proteínas Hemolisinas/genética , Proteínas de Insetos/genética , Larva/genética , Larva/metabolismo , Ligação Proteica
15.
Animal ; 14(S1): s113-s123, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32024568

RESUMO

Methane (CH4) production is a ubiquitous, apparently unavoidable side effect of fermentative fibre digestion by symbiotic microbiota in mammalian herbivores. Here, a data compilation is presented of in vivo CH4 measurements in individuals of 37 mammalian herbivore species fed forage-only diets, from the literature and from hitherto unpublished measurements. In contrast to previous claims, absolute CH4 emissions scaled linearly to DM intake, and CH4 yields (per DM or gross energy intake) did not vary significantly with body mass. CH4 physiology hence cannot be construed to represent an intrinsic ruminant or herbivore body size limitation. The dataset does not support traditional dichotomies of CH4 emission intensity between ruminants and nonruminants, or between foregut and hindgut fermenters. Several rodent hindgut fermenters and nonruminant foregut fermenters emit CH4 of a magnitude as high as ruminants of similar size, intake level, digesta retention or gut capacity. By contrast, equids, macropods (kangaroos) and rabbits produce few CH4 and have low CH4 : CO2 ratios for their size, intake level, digesta retention or gut capacity, ruling out these factors as explanation for interspecific variation. These findings lead to the conclusion that still unidentified host-specific factors other than digesta retention characteristics, or the presence of rumination or a foregut, influence CH4 production. Measurements of CH4 yield per digested fibre indicate that the amount of CH4 produced during fibre digestion varies not only across but also within species, possibly pointing towards variation in microbiota functionality. Recent findings on the genetic control of microbiome composition, including methanogens, raise the question about the benefits methanogens provide for many (but apparently not to the same extent for all) species, which possibly prevented the evolution of the hosting of low-methanogenic microbiota across mammals.


Assuntos
Fibras na Dieta/metabolismo , Mamíferos/metabolismo , Metano/metabolismo , Animais , Dieta/veterinária , Digestão , Sistema Digestório/metabolismo , Fermentação , Herbivoria , Rúmen/metabolismo , Ruminantes/metabolismo
16.
Pestic Biochem Physiol ; 163: 241-253, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31973864

RESUMO

Spodoptera exigua nucleopolyhedrovirus (SeNPV) has been successfully applied as a bioinsecticide against S. exigua, one of the most devastating pests worldwide. However, due to limited information, the molecular mechanisms underlying interactions between S. exigua and SeNPV remain to be elucidated. In this study, RNA-Seq and differentially expressed gene (DEG) analysis of the S. exigua larva midgut were performed to explore molecular responses to SeNPV infection. A total of 1785 DEGs, including 935 upregulated and 850 downregulated genes, were identified in the midgut of SeNPV-infected S. exigua larvae. Ultrastructural observations showed that after SeNPV infection, the peritrophic matrix (PM) became a loose and highly porous surface with many clear ruptures; these changes were most likely associated with upregulation of chitin deacetylases. In addition, 124 putative innate immunity-related DEGs were identified and divided into several groups, including pattern recognition proteins, signaling pathways, signal modulation, antimicrobial peptides and detoxification. Interestingly, upregulation of some pattern recognition proteins, induction of the JAK/STAT signaling pathway and promotion of REPAT synthesis might be the main innate immunity responses occurring in the S. exigua larva midgut after SeNPV infection. According to quantitative real-time PCR, the expression profiles of 19 random DEGs were consistent with those obtained by RNA-Seq. These findings provide important basic information for understanding the molecular mechanisms of SeNPV invasion and the anti-SeNPV responses of the S. exigua midgut, promoting the utility of SeNPV as a bioinsecticide for the effective control of S. exigua and related pests.


Assuntos
Nucleopoliedrovírus , Animais , Sistema Digestório , Larva , Spodoptera , Transcriptoma
17.
Parasit Vectors ; 13(1): 3, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31907025

RESUMO

BACKGROUND: Malaria remains to be one of the deadliest infectious diseases and imposes substantial financial and social costs in the world. Mosquitoes rely on the immune system to control parasite infection. Peptidoglycan recognition proteins (PGRPs), a family of pattern-recognition receptors (PRR), are responsible for initiating and regulating immune signaling pathways. PGRP-LA is involved in the regulation of immune defense against the Plasmodium parasite, however, the underlying mechanism needs to be further elucidated. METHODS: The spatial and temporal expression patterns of pgrp-la in Anopheles stephensi were analyzed by qPCR. The function of PGRP-LA was examined using a dsRNA-based RNA interference strategy. Western blot and periodic acid schiff (PAS) staining were used to assess the structural integrity of peritrophic matrix (PM). RESULTS: The expression of pgrp-la in An. stephensi was induced in the midgut in response to the rapid proliferating gut microbiota post-blood meal. Knocking down of pgrp-la led to the downregulation of immune effectors that control gut microbiota growth. The decreased expression of these immune genes also facilitated P. berghei infection. However, such dsLA treatment did not influence the structural integrity of PM. When gut microbiota was removed by antibiotic treatment, the regulation of PGRP-LA on immune effectors was abolished and the knock down of pgrp-la failed to increase susceptibility of mosquitoes to parasite infection. CONCLUSIONS: PGRP-LA regulates the immune responses by sensing the dynamics of gut microbiota. A mutual interaction between gut microbiota and PGRP-LA contributes to the immune defense against Plasmodium parasites in An. stephensi.


Assuntos
Anopheles/imunologia , Anopheles/microbiologia , Proteínas de Transporte/imunologia , Microbioma Gastrointestinal , Proteínas de Insetos/imunologia , Mosquitos Vetores/microbiologia , Plasmodium berghei/fisiologia , Animais , Anopheles/genética , Proteínas de Transporte/genética , Sistema Digestório/imunologia , Sistema Digestório/microbiologia , Interações Hospedeiro-Parasita , Proteínas de Insetos/genética , Mosquitos Vetores/genética , Mosquitos Vetores/imunologia
18.
Proc Natl Acad Sci U S A ; 117(3): 1514-1523, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31915294

RESUMO

Studies of the adult Drosophila midgut have led to many insights in our understanding of cell-type diversity, stem cell regeneration, tissue homeostasis, and cell fate decision. Advances in single-cell RNA sequencing provide opportunities to identify new cell types and molecular features. We used single-cell RNA sequencing to characterize the transcriptome of midgut epithelial cells and identified 22 distinct clusters representing intestinal stem cells, enteroblasts, enteroendocrine cells (EEs), and enterocytes. This unbiased approach recovered most of the known intestinal stem cells/enteroblast and EE markers, highlighting the high quality of the dataset, and led to insights on intestinal stem cell biology, cell type-specific organelle features, the roles of new transcription factors in progenitors and regional variation along the gut, 5 additional EE gut hormones, EE hormonal expression diversity, and paracrine function of EEs. To facilitate mining of this rich dataset, we provide a web-based resource for visualization of gene expression in single cells. Altogether, our study provides a comprehensive resource for addressing functions of genes in the midgut epithelium.


Assuntos
Sistema Digestório/metabolismo , Drosophila/metabolismo , Células-Tronco/metabolismo , Transcriptoma , Animais , Sistema Digestório/citologia , Drosophila/citologia , Drosophila/genética , Proteínas de Drosophila/metabolismo , Enterócitos/metabolismo , Células Enteroendócrinas/metabolismo , Células Epiteliais/metabolismo , Epitélio/metabolismo , Regulação da Expressão Gênica , Hormônios/metabolismo , Intestinos/citologia , Células-Tronco/citologia , Fatores de Transcrição/metabolismo
19.
Chemosphere ; 247: 125877, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31935578

RESUMO

Boron nitride nanosheets (BN NSs), a novel material with a structure similar to graphene, have attracted much attention due to their extraordinary properties. A deep in vivo study of the toxicity of BN NSs is indispensable, which can help to understand their potential risk and provide useful information for their safe application. However, so far as we know, the systematic in vivo toxicity evaluation of BN NSs hasn't been reported. In this study, silkworm (Bombyx mori) was used as a model to investigate the toxicity of BN NSs, by continuously feeding silkworm larvae with BN NSs at various mass concentrations (1%, 2%, 3%, 4%). The toxicity was evaluated from the levels of animal entirety (mortality, silkworm growth, cocoons and silk properties), tissues (pathological examination) and genes (transcriptomic profiling). The results show that the exposure to BN NSs causes no obvious adverse effects on the growth, silk properties or tissues of silkworm, but the expressions of genes in midgut concerned with some specific functions and pathways are significantly changed, indicating that BN NSs may have potential danger to lead to dysfunction. This study has performed in vivo toxicity evaluation of BN NSs and provided useful safety information for the application of BN NSs.


Assuntos
Bombyx/fisiologia , Compostos de Boro/toxicidade , Nanoestruturas/toxicidade , Animais , Sistema Digestório , Perfilação da Expressão Gênica , Grafite/metabolismo , Larva
20.
Anat Histol Embryol ; 49(1): 31-37, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31571240

RESUMO

The distribution of glucagon-like peptide 1 (GLP-1)-positive cells in digestive tracts and pancreases of aquatic vertebrates was investigated by immunohistochemical staining method. The results suggested that GLP-1-positive cells were distributed in the columnar mucous epithelium and tubular glands of lamina propria in the digestive system. However, GLP-1-positive cells were also found in subepithelial lamina propria of the mucosae and muscularis in each segment of the digestive tract of Rana nigromaculata. The distribution densities of these cells reached peaks in the stomachs, and the middle or end segments of small intestines of Chinese softshell turtle, Bufo gargarizans, R. nigromaculata and catfish, and there was the third distribution density peak in the rectum of catfish. The total amount or overall density of GLP-1-positive cells varied a lot in the digestive tracts of different animal species. The distribution density was relatively low in the digestive tract of chub and reached the maximum in the digestive tracts of snakehead and catfish, but no GLP-1-positive cells were found in the digestive tract of bighead carp. GLP-1-positive cells were densely distributed in the pancreases of Chinese softshell turtle, B. gargarizans and R. nigromaculata. These cells spread over the superficial layers of islets or scattered in exocrine pancreas in the pancreas of B. gargarizans, spread in the endocrine cells or scattered in the pancreas of Chinese softshell turtle, scattered in the pancreas of R. nigromaculata and distributed in the superficial layers of islets in the pancreas of catfish.


Assuntos
Sistema Digestório/citologia , Sistema Digestório/metabolismo , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Anfíbios/metabolismo , Animais , Organismos Aquáticos/metabolismo , Células Epiteliais/metabolismo , Peixes/metabolismo , Imuno-Histoquímica , Membrana Mucosa/citologia , Membrana Mucosa/metabolismo , Pâncreas/citologia , Pâncreas/metabolismo , Tartarugas/metabolismo , Vertebrados/metabolismo
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