588 research outputs found
Caracterização do meio fÃsico da Bacia Hidrográfica do Rio da Prata, Mato Grosso do Sul.
Caracterização do meio fÃsico; Localização; Altimetria; Solos; Recursos hÃdricos.bitstream/item/38332/1/DOC41.pd
Detection of Malawi polyomavirus sequences in secondary lymphoid tissues from Italian healthy children: a transient site of infection
BACKGROUND:
The novel Malawi polyomavirus (MWPyV) was initially detected in stool specimens from healthy children and children with gastrointestinal symptoms, mostly diarrhea, indicating that MWPyV might play a role in human gastroenteric diseases. Recently, MWPyV sequences were additionally identified in respiratory secretions from both healthy and acutely ill children suggesting that MWPyV may have a tropism for different human tissues. This study was designed to investigate the possible sites of latency/persistence for MWPyV in a cohort of healthy Italian children.
METHODS:
Specimens (n\ub0 500) of tonsils, adenoids, blood, urines and feces, from 200 healthy and immunocompetent children (age range: 1-15 years) were tested for the amplification of the MWPyV LT antigen sequence by quantitative real-time PCR. Samples (n\ub0 80) of blood and urines from 40 age-matched children with autoimmune diseases, were screened for comparison. Polyomaviruses JC/BK and Epstein-Barr Virus (EBV) were also tested as markers of infection in all samples using the same molecular technique.
RESULTS:
In our series of healthy children, MWPyV was detected only in the lymphoid tissues showing a prevalence of 6 % in tonsils and 1 % in adenoids, although with a low viral load. No JCPyV or BKPyV co-infection was found in MWPyV positive samples, while EBV showed a similar percentage of both in tonsils and adenoids (38 and 37 %). Conversely, no MWPyV DNA was detected in stool from babies with gastroenteric syndrome. With regards to autoimmune children, neither MWPyV nor BKPyV were detected in blood, while JCPyV viremia was observed in 15 % (6/40) of children treated with Infliximab. Urinary BKPyV shedding was observed in 12.5 % (5/40) while JCPyV in 100 % of the samples.
CONCLUSIONS:
The detection of MWPyV sequences in tonsils and adenoids of healthy children suggests that secondary lymphoid tissues can harbour MWPyV probably as transient sites of persistence rather than actual sites of latency
Social distancing measures for COVID-19 are changing winter season
Health authorities worldwide have
adopted measures of social distancing
and movement restrictions, in addition
to other public health measures to reduce
exposure and to suppress interhuman
SARS-CoV-
2 transmission. In Italy, a
national lockdown with school closure
was introduced from March to May 2020.
From November 2020, Italy has been
divided into zones according to regional
epidemiological data, with primary
schools reopened, associated with the
mandatory use of face masks and different
levels of social distance measures. For
children with symptoms suggestive of
COVID-19, the surveillance mechanism
for the control of SARS-CoV-
2 infection
is based on the performance of a real-time
PCR on a nasopharyngeal swab. A
diagnostic test has been introduced at the
tertiary-level
university hospital, Institute
for Maternal and Child Health, IRCCS
\u201cBurlo Garofolo\u201d of Trieste, consisting of
a multiple nucleic acid amplification assay
for 13 common viral respiratory pathogens
on nasopharyngeal swab (Respiratory
Flow Chip assay (Vitro, Sevilla,
Spain), including SARS-CoV-
2, influenza
A and B, adenovirus, other coronaviruses,
parainfluenza virus 1\u20134, enteroviruses,
bocavirus, metapneumovirus, respiratory
syncytial virus (RSV), rhinoviruses, Bordetella
pertussis, Bordetella parapertussis
and Mycoplasma pneumoniae. Before
routine utilisation, international standard
quality control samples for each pathogen
were used for test validation, and no
cross-detection
was found between the
different pathogens. Criteria for testing
referral did not change during the study
period. Weekly variability of the number
of total tests performed was due to the
normal variations of acute illness. During
the last winter season, from September
2020 (week 39) to February 2021 (week
7), 1138 nasopharyngeal swabs were
tested for patients younger than 17 years
old (figure 1). No influenza A or B nor
RSV was detected during this period.
The most common pathogen was rhinovirus
(n=505), followed by adenoviruses
(n=131), other coronaviruses (n=101)
and SARS-CoV-
2 (n=57). Our data show
that common winter pathogens circulation
changed, and influenza virus and RSV
did not produce a seasonal epidemic in
the 2020\u20132021 winter season. These data
suggest that social distancing measures
and mask wearing profoundly changed
the seasonality of winter paediatric respiratory
infections that are mainly spread
by respiratory droplets. The reasons why
rhinovirus remains the main pathogen
despite social distancing and face mask
use are still a matter of debate. Similar
data showing a decrease of common viral
respiratory infections during the winter
season have recently been reported in the
southern hemisphere.1\u20134 Our data refer
to a single institute, covering paediatric
population of the Trieste Province (about
230 000 inhabitants), limiting the generalisation
of our findings. However, our
results highlight the need for continuing
surveillance for the delayed spread of such
viruses during spring and summer
The Vaginal Community State Types Microbiome-Immune Network as Key Factor for Bacterial Vaginosis and Aerobic Vaginitis
Regarding bacterial vaginosis (BV), the relevance of the vaginal microbiota to the women's health fulfills a key role, but knowledge gaps regarding aerobic vaginitis (AV) exist. This study aims to characterize vaginal microbiome and its relationship with the local immune mediators, providing an opportunity to define the link between vaginal commensal microorganisms and opportunistic pathogens in the relation of a given vaginal community state type (CST). A total of 90 vaginal samples from Caucasian asymptomatic women of reproductive age (18-40 years) attending the yearly examination and not reporting any vaginal complaints were retrospectively evaluated for microbiome assessment and immune factor dosage. The samples were tested by the Ion Torrent PGM and the Luminex Bio-Plex technologies for the analysis of microbiome and immune factors, respectively. In our study, the CST classification together with the local immune response profiling represented a good predictive indicator of the vaginal health, suggesting that the predominance of a specific Lactobacillus and its relative abundance are pivotal elements to maintain a physiologic status. A vaginal colonization from Bifidobacterium may absolve a protective role similar to that of Lactobacillus, corresponding to a newly identified CST, although studies are needed to better clarify its clinical significance. Moreover, within each CST, a different pattern of inflammation is activated and orchestrated both by the dominant Lactobacillus spp. and by specific non-Lactobacillus bacteria and can give insights into the pathogenic mechanisms. In conclusion, this study contributes to the characterization of vaginal dysbiosis, reshaping this concept by taking into consideration the CST profiling, local immune marker, and immune-microbial network
Changes in Gut Microbiota Composition after Bariatric Surgery: a New Balance to Decode
Background: Recently, the link between obesity and gut microbiota has become a focus for research. This study shed some light on the modification of postoperative gut microbial composition after bariatric surgery. Methods: A prospective longitudinal study on healthy lean subjects and patients who underwent bariatric surgery (Roux-en-Y gastric bypass and laparoscopic sleeve gastrectomy) was carried out. Anthropometric and metabolic data, smoking, food preferences data, and stool samples were collected from lean subjects and from obese patients before and 3 and 6\ua0months after surgery (T0, T3, and T6, respectively). Results: We collected stool samples from 25 obese patients before surgery and 3 and 6\ua0months thereafter and from 25 normal weight patients. After Roux-en-Y gastric bypass, Yokenella regensburgei (p < 0.05), Fusobacterium varium (p < 0.05), Veillonella dispar/atypica (p < 0.05), and Streptococcus australis/gordonii (p < 0.05) were transiently identified in the gut at T3. Roux-en-Y gastric bypass patients had a permanent increase in Akkermansia muciniphila (p < 0.05), which is associated with healthy metabolism, both at T3 and T6. There were no significant changes in gut microbiota in laparoscopic sleeve gastrectomy patients. Conclusions: In our study, Roux-en-Y gastric bypass induced major microbial differences and greater weight loss compared with laparoscopic sleeve gastrectomy. Analyzing the microbiota composition, a proliferation of potential pathogens and the onset of beneficial bacteria was observed. The effects of these bacteria on human health are still far from clear. Understanding the mechanisms of action of these bacteria could be the keystone in developing new therapeutic strategies for obesity
Copper modulates the biochemical and enzymatic activity and growth of tomato cultivars grown in vitro
Received: August 25th, 2020 ; Accepted: December 17th, 2020 ; Published: February 09th, 2021 ; Correspondence: [email protected] (Cu) is a micronutrient that is neglected for tomato growth. This study sought
to identify the effects of exposure to Cu on the growth and biochemical activity of two tomato
cultivars. Tomato seeds of ‘Carolina’ and ‘Cereja’ cultivars were disinfected and inoculated in
MS medium plus copper sulfate concentrations (CuSO4) (default MS, 25, 50, and 100 µm) and
had their growth monitored for 30 days. It was estimated that the growth and biomass
accumulation of tomato plants ‘Carolina’ and ‘Cereja’, both from the aerial part and the roots,
were benefited by 25 e 50 µm of CuSO4. However, it was observed that these concentrations were
inefficient in controlling hyperhydricity and leaf deformation. There was a reduction of these
phenomena in the treatment with 100 µm, in both cultivars. Tomato of ‘Carolina’ cultivar
subjected to 100 µm showed an increase in anthocyanins and superoxide dismutase (SOD)
activity in the root system. There was a reduction of catalase (CAT) activity in shoots exposed to
Cu. ‘Cereja’ tomatoes subjected to 100 µm showed an increase in CAT and SOD activity in
shoots and roots, respectively. It was concluded that the ‘Carolina’ and ‘Cereja’ tomatoes have
their growth impaired when exposed to 100 µm CuSO4. Concentrations higher than 50 µm of
CuSO4 cause an increase in the antioxidant activity in the shoot of tomato plants from the
‘Carolina’ cultivar. Concentrations higher than 50 µm CuSO4 increase SOD activity in the root
system of tomato plants from the ‘Cereja’ cultivar
Impact of experimental Nano-HAP pastes on bovine enamel and dentin submitted to a pH cycling model
This in vitro study evaluated the preventive potential of experimental pastes containing 10% and 20% hydroxyapatite nanoparticles (Nano-HAP), with or without fluoride, on dental demineralization. Bovine enamel (n=15) and root dentin (n=15) specimens were divided into 9 groups according to their surface hardness: control (without treatment), 20 Nanop paste (20% HAP), 20 Nanop paste plus (20% HAP + 0.2% NaF), 10 Nanop paste (10% HAP), 10 Nanop paste plus (10% HAP + 0.2% NaF), placebo paste (without fluoride and HAP), fluoride paste (0.2% NaF), MI paste (CPP-ACP, casein phosphopeptide-amorphous calcium phosphate), and MI paste plus (CPP-ACP + 0.2% NaF). Both MI pastes were included as commercial control products containing calcium phosphate. The specimens were treated with the pastes twice a day (1 min), before and after demineralization. The specimens were subjected to a pH-cycling model (demineralization–6-8 h/ remineralization-16-18 h a day) for 7 days. The dental subsurface demineralization was analyzed using cross-sectional hardness (kgf/mm 2 , depth 10-220 µm). Data were tested using repeated-measures two-way ANOVA and Bonferroni's test (p<0.05). The only treatment able to reduce the loss of enamel and dentin subsurface hardness was fluoride paste (0.2% NaF), which differed significantly from the control at 30- and 50-µm depth (p<0.0001). The other treatments were not different from each other or compared with the control. The experimental Nanop pastes, regardless of the addition of fluoride, were unable to reduce dental demineralization in vitro
Measles: An overview of a re-emerging disease in children and immunocompromised patients
Despite the availability of a safe and effective vaccine, in 2018, around 350,000 measles cases were reported worldwide, which resulted in an estimate of 142,300 deaths from measles. Additionally, in 2017, global measles cases spiked, causing the death of 110,000 people, mostly children under the age of 5 years and immunocompromised adults. The increase in measles incidence is caused by the ongoing reduction of vaccination coverage. This event has triggered public and scientific interest. For this reason, we reviewed the pathophysiology of measles infection, focusing on mechanisms by which the virus spreads systemically through the host organism. By reaching the lymphocytes from the airways through a \u201ctrojan horse\u201d strategy, measles induces an immunosuppression status. H and F glycoproteins, both expressed in the envelope, ensure attachment of the virus to host cells and spreading from one cell to another by binding to several receptors, as described in detail. The severity of the disease depends both on the age and underlying conditions of patients as well as the social and health context in which epidemics spread, and is often burdened by sequelae and complications that may occur several years after infection. Particular attention was paid to special groups that are more susceptible to severe or atypical measles. An overview of microbiology, symptoms, diagnosis, prevention, and treatment completes and enriches the review
Human Polyomaviruses in the Cerebrospinal Fluid of Neurological Patients.
BACKGROUND:
Central nervous system (CNS) infections by human polyomaviruses (HPyVs), with the exception of JC (JCPyV), have been poorly studied.
METHODS:
In total, 234 cerebrospinal fluid (CSF) samples were collected from patients affected with neurological disorders. DNA was isolated and subjected to quantitative real-time PCR (Q-PCR) for the detection of six HPyVs: JCPyV, BKPyV, Merkel cell PyV (MCPyV), HPyV6, HPyV7, and HPyV9. Where possible, the molecular characterization of the viral strains was carried out by nested PCR and automated sequencing.
RESULTS:
JCPyV was detected in 3/234 (1.3%), BKPyV in 15/234 (6.4%), MCPyV in 22/234 (9.4%), and HPyV6 in 1/234 (0.4%) CSF samples. JCPyV was detected at the highest (p < 0.05) mean load (3.7
7 107 copies/mL), followed by BKPyV (1.9
7 106 copies/mL), MCPyV (1.9
7 105 copies/mL), and HPyV6 (3.3
7 104 copies/mL). The noncoding control regions (NCCRs) of the sequenced viral strains were rearranged.
CONCLUSIONS:
HPyVs other than JCPyV were found in the CSF of patients affected with different neurological diseases, probably as bystanders, rather than etiological agents of the disease. However, the fact that they can be latent in the CNS should be considered, especially in immunosuppressed patients
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