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71.
Hantaviruses are zoonotic viruses harbored by rodents, bats, and shrews. At present, only rodent-borne hantaviruses are associated with severe illness in humans. New species of hantaviruses have been recently identified in bats and shrews greatly expanding the potential reservoirs and ranges of these viruses. Brazil has one of the highest incidences of hantavirus cardiopulmonary syndrome in South America, hence it is critical to know what is the prevalence of hantaviruses in Brazil. Although much is known about rodent reservoirs, little is known regarding bats. We captured 270 bats from February 2012 to April 2014. Serum was screened for the presence of antibodies against a recombinant nucleoprotein (rN) of Araraquara virus (ARAQV). The prevalence of antibody to hantavirus was 9/53 with an overall seroprevalence of 17%. Previous studies have shown only insectivorous bats to harbor hantavirus; however, in our study, of the nine seropositive bats, five were frugivorous, one was carnivorous, and three were sanguivorous phyllostomid bats.Hantaviruses (family Bunyaviridae) are present throughout the globe in rodents, bats, and shrews.1 Humans exposed to rodent excreta from hantaviral reservoirs may develop life-threatening diseases. However, none of the other reservoirs are associated with human illness presently.1,2 Bats (order Chiroptera) are known to harbor a broad diversity of emerging zoonotic pathogens.2 Their ability to fly and social behavior favors maintenance, evolution, and spread of pathogens.1,2 The prevailing hypothesis has been that hantaviruses have coevolved with their rodent reservoirs over millions of years.1,3 With the recognition of new species of hantavirus in bats in Africa and Asia,4 Guo and others5 hypothesized that hantaviruses originated primarily in bats and then spilled over into rodents and shrews, but it seems that shrews are the original hosts from which the viruses jumped into both rodents and bats.3 To determine if New World bats in Brazil may harbor hantaviruses, we screened bat sera for antibodies that react against the recombinant nucleoprotein (rN) of Araraquara hantavirus (ARAQV).Bats were collected at five ecologically distinct sites in the northeast region of São Paulo state (sites 1–3) and north region of Minas Gerais state (sites 4 and 5), southeastern Brazil (Figure 1 and 9 and one specimen per species by trap-night was anesthetized to collect blood by cardiac puncture; blood samples were stored in cryovials and flash-frozen in liquid nitrogen. At sites 4 and 5, five specimens per trap-night were randomly selected for blood collection. All bats were handled and sampled according to Sikes and others10 guidelines. This research project, along with its procedures and protocols, is in accordance with Brazilian environment and wildlife protection laws and regulations, and have been approved by the Chico Mendes Institute of Biodiversity Conservation (Ministry of Environment, Brasília, Distrito Federal, Brazil.), protocols nos. 19838-1 and 41709-3. It has also been approved by the Ethics Committee for Animal Research of University of São Paulo and Federal University of Minas Gerais (nos. 020/2011 and 333/2013, respectively). From 270 captured bats, 53 were bled for detection of immunoglobulin G (IgG) antibodies to rN-ARAQV by indirect enzyme-linked immunosorbent assay (ELISA) using anti-bat (Bethyl Laboratories, Inc., Montgomery, TX) secondary antibody. This ELISA, as previously described, showed 97.2% sensitivity, 100% specificity, 100% positive predictive value, and 98.1% negative predictive value when compared with an IgG-ELISA using rN antigen of Andes virus, which is the serological test for hantavirus most used in South America.11,12Open in a separate windowFigure 1.Study areas, highlighting the states of São Paulo and Minas Gerais in southeastern Brazil. The map shows cities where bats have been captured.

Table 1

Trap sites general features6
Trap sites/altitude (m)City/stateMain vegetationSecondary vegetationFeatures
1JES/600Luis Antonio/SPCerrado*Semideciduous forestContinuous Cerrado
2NEF/775Cajuru/SPGrasslandCerradoMonocultures
3SGF/860Batatais/SPSugarcaneCerradoMonocultures
4SEP/872Montes Claros/MGDry forest7CerradoKarst topography
5LGEP/1,009Montes Claros/MGCerrado8Gallery forestCaves and shelters
Open in a separate windowJES = Jatai Ecological Station; LGEP = Lapa Grande Ecological Park; MG = Minas Gerais state; NEF = Nova Esperança Farm; SEP = Sapucai Ecological Park; SGF = Santa Gabriela Farm; SP = Sao Paulo state.*Cerrado = Brazilian savanna-like biome.Dry forest = deciduous seasonal forest.Nine bats had IgG antibodies to ARAQV, which represents an overall seroprevalence of 17%. Five of these bats were from São Paulo state and four were from Minas Gerais state. Of these, five were frugivorous, one was carnivorous, and three were sanguivorous (
FamilySpeciesCapturedInfected/testedMain feeding items
PhyllostomidaeArtibeus lituratus411/6Fruits
PhyllostomidaeA. obscurus21/2Fruits
PhyllostomidaeA. planirostris411/3Fruits
PhyllostomidaeCarollia perspicillata431/10Fruits and insects
PhyllostomidaeChiroderma villosum11/1Fruits
PhyllostomidaeChrotopterus auritus11/1Small vertebrates
PhyllostomidaeDesmodus rotundus113/5Mammals blood
PhyllostomidaeGlossophaga soricina220/5Nectar and pollen
PhyllostomidaeLonchophylla spp.10/1Nectar and pollen
PhyllostomidaeMicronycteris minuta10/1Insects
MolossidaeMolossops neglectus10/1Insects
MolossidaeMolossops temminckii20/1Insects
VespertilionidaeMyotis nigricans130/5Insects
VespertilionidaeMyotis albescens40/1Insects
PhyllostomidaePlatyrrhinus lineatus230/4Fruits
PhyllostomidaeSturnira lilium380/6Fruits
Open in a separate windowrN-ARAQV = recombinant nucleoprotein of Araraquara virus.Main feeding items are shown according to Gardner.9Bats evolution is dated around 50 million years ago, and they are distributed widely in the world, on all continents, except Antarctica.2,13 Perhaps, because of their ancient origin certain viruses seem to be coevolved with them. Thus, maintenance and transmission of these viruses crossed species barriers to infect wild and domestic mammals and also humans.2,13,14 Antibodies to viruses such as Hendra, Ebola, and severe acute respiratory syndrome (SARS)-like coronavirus (CoV) have been detected in wild bats, demonstrating that these animals are able to mount an antibody response, including IgM, IgE, IgA, and multiple IgG classes.14 Although bats may be persistently infected with many viruses, evidence from experimental and naturally infected bats has shown that they rarely produce an antibody response, probably because they are able to control viral replication via the innate immune antiviral response, and therefore, show a low viremia.13,14 However, here we were capable to show bats with IgG antibodies against the rN-ARAQV. The ELISA essays using rN-ARAQV as antigen have been previously used in hantavirus serologic surveys in rodents.15,16 Previous studies with bats of the Old World showed that only insectivorous bats are infected with hantavirus.5 Our study emphasizes that hantaviruses are infecting bats of several species and of different trophic groups in Brazil (15,16 Despite, we have found antibodies against hantavirus, our results only support the idea that these bats become infected in some moment of their lifetime. Further studies in bats are necessary to detect the species and genotype of the infecting hantavirus and then determine the viral load in distinct organ tissues of these animals. Therefore, virus isolation followed by infection experiments could provide additional information if bats actually play a role as reservoirs of hantaviruses. Regardless of the negative public impression of bats, they possess important roles on insect control,17 reseeding forests, and pollinate plants that provide human and animal food.18 Bat guano is used as a fertilizer and for manufacturing soaps, gasohol, and antibiotics. Besides, bat echolocation and the infrared radiation of vampire bats (Desmodus rotundus) have provided models for sonar and infrared systems, respectively.13,19Our study gives insights into ecology, conservational biology, and public health. These data may be useful to understand patterns of hantavirus evolution, in bats and other reservoirs, and to understand the virus dynamics and their potential public health importance. It is also important to preserve the native environment of these animals. Hence, this is the first report of the presence of hantavirus antibodies in phyllostomid bats in southeastern Brazil and also the first report of hantavirus antibodies among bats in the Americas.  相似文献   
72.
Temporal resolution in individuals with neurological disorders     
Camila Maia Rabelo  Jeffrey A Weihing  Eliane Schochat 《Clinics (S?o Paulo, Brazil)》2015,70(9):606-611

OBJECTIVE:

Temporal processing refers to the ability of the central auditory nervous system to encode and detect subtle changes in acoustic signals. This study aims to investigate the temporal resolution ability of individuals with mesial temporal sclerosis and to determine the sensitivity and specificity of the gaps-in-noise test in identifying this type of lesion.

METHOD:

This prospective study investigated differences in temporal resolution between 30 individuals with normal hearing and without neurological lesions (G1) and 16 individuals with both normal hearing and mesial temporal sclerosis (G2). Test performances were compared, and the sensitivity and specificity were calculated.

RESULTS:

There was no difference in gap detection thresholds between the two groups, although G1 revealed better average thresholds than G2 did. The sensitivity and specificity of the gaps-in-noise test for neurological lesions were 68% and 98%, respectively.

CONCLUSIONS:

Temporal resolution ability is compromised in individuals with neurological lesions caused by mesial temporal sclerosis. The gaps-in-noise test was shown to be a sensitive and specific measure of central auditory dysfunction in these patients.  相似文献   
73.
Transient neonatal diabetes due to a missense mutation (E227K) in the gene encoding the ATP‐sensitive potassium channel (KCNJ11)     
Luísa Martins  Rita Loureno  Ana Lúcia Maia  Paula Maciel  Maria Isabel Monteiro  Lucinda Pacheco  Joo Anselmo  Rui Csar  Maria Fernanda Gomes 《Clinical Case Reports》2015,3(10):781-785
Neonatal diabetes is a monogenic form of diabetes. Herein, we report on a newborn presenting diabetic ketoacidosis at 17 days of life . A KCNJ11 mutation was identified. In such cases, insulin can be replaced by sulfonylurea with a successful metabolic control, as an example of how molecular diagnosis may influence the clinical management of the disorder.  相似文献   
74.
The morphological and molecular characterization of Henneguya rotunda n. sp., a parasite of the gill arch and fins of Salminus brasiliensis from the Mogi Guaçu River,Brazil     
Gabriel S. A. Moreira  Edson A. Adriano  Marcia R. M. Silva  Paulo S. Ceccarelli  Antônio A. M. Maia 《Parasitology research》2014,113(5):1703-1711
A new species of myxosporea (Henneguya rotunda n. sp.) was found in the membrane of the gill arch and the fins of Salminus brasiliensis in the Mogi Guaçu River, municipality of Pirassununga, São Paulo state, Brazil. Morphological and morphometric analyses using light microscopy revealed parasites with similar characteristics at both infection sites. The mature spores found infecting the fins had oval spore body with 7.1?±?0.2 μm in length, 5.6?±?0.2 μm in width, 3.7?±?0.1 μm in thickness, 16.4?±?1.2 μm in length of the caudal process, and 23.6?±?1.1 μm in total length of the spore. In a frontal view, the polar capsule was observed to be symmetrical with 3.4?±?0.2 μm in length and 1.8?±?0.1 μm in width. Mature spores contain six to seven turns of the polar filaments. The morphometric data concerning the spores obtained from plasmodia from the membrane of the gill arch were similar to those from the fins. Ultrastructure analysis revealed that the plasmodial wall was formed by a single membrane and had numerous pinocytotic canals connecting the outside of the plasmodia to the ectoplasm zone. Beyond that, various electron-translucent vesicles also were observed at the periphery of the plasmodium. The molecular analyses of the 18S rDNA gene from the spores obtained from the gill arch membrane and fin membrane showed that these sequences shared 100 % similarity. Phylogenetic studies using maximum parsimony and maximum likelihood methods demonstrated the polyphyletic clustering of the myxosporean parasites of characiform fishes. H. rotunda n. sp. clustered as a sister species of Myxobolus pantanalis, also a parasite of S. brasiliensis.  相似文献   
75.
Best practice for PTEN gene and protein assessment in anatomic pathology     
Kátia C. Carvalho  Beatriz M. Maia  Samantha V. Omae  Antonio A. Rocha  Luiz P. Covizzi  José Vassallo  Rafael M. Rocha  Fernando A. Soares 《Acta histochemica》2014
There is a lack of standardization of a best practice protocol for Phosphatase and Tensin Homolog (PTEN) assessment by immunohistochemistry in anatomic pathology routine practice. We performed immunohistochemistry for 19 antibodies against PTEN, eleven of which were excluded during the standardization step. Immunohistochemistry of the remaining eight antibodies was performed on a Tissue Microarray containing 55 prostate and 40 renal carcinoma samples. Fluorescent in situ hybridization (FISH) was used as reference standard for immunohistochemistry specificity evaluation. Concerning nuclear staining, polyclonal (Cat#22034-1-AP); 6H2.1 mMAb (Cat#ABM-2052), Y184 RabMAb (Cat#NB110-57441) and 217702 mMAb antibodies presented the highest agreement with fluorescent in situ hybridization (p < 0.001 for all) and with regard to cytoplasmic staining, Y184 RabMAb (Cat#NB110-57441); polyclonal (Cat#22034-1-AP) and 217702 mMAb presented the highest agreement (p < 0.001 for all). Our results indicate that several commercially available antibodies do not show reliability of sensitivity and specificity for PTEN evaluation and we propose 6H2.1 mMAb (Cat#ABM-2052) as the antibody of choice for laboratory standardization and best practice in clinical routine, which demonstrated excellent sensitivity for both nuclear and cytoplasmic staining, specificity for PTEN by Western blot and good correlation with PTEN status by FISH with regard to nuclear staining.  相似文献   
76.
QUANTITATIVE REAL-TIME PCR (Q-PCR) FOR SPUTUM SMEAR DIAGNOSIS OF PULMONARY TUBERCULOSIS AMONG PEOPLE WITH HIV/AIDS     
Yvana Maria Maia de Albuquerque  Ana Luiza Magalh?es de Andrade Lima  Ana Kelly Lins  Marcelo Magalh?es  Vera Magalh?es 《Revista do Instituto de Medicina Tropical de S?o Paulo》2014,56(2):139-142
Objective: To assess quantitative real-time polymerase chain reaction (q-PCR) for the sputum smear diagnosis of pulmonary tuberculosis (PTB) in patients living with HIV/AIDS with a clinical suspicion of PTB. Method: This is a prospective study to assess the accuracy of a diagnostic test, conducted on 140 sputum specimens from 140 patients living with HIV/AIDS with a clinical suspicion of PTB, attended at two referral hospitals for people living with HIV/AIDS in the city of Recife, Pernambuco, Brazil. A Löwenstein-Jensen medium culture and 7H9 broth were used as gold standard. Results: Of the 140 sputum samples, 47 (33.6%) were positive with the gold standard. q-PCR was positive in 42 (30%) of the 140 patients. Only one (0.71%) did not correspond to the culture. The sensitivity, specificity and accuracy of the q-PCR were 87.2%, 98.9% and 95% respectively. In 39 (93%) of the 42 q-PCR positive cases, the CT (threshold cycle) was equal to or less than 37. Conclusion: q-PCR performed on sputum smears from patients living with HIV/AIDS demonstrated satisfactory sensitivity, specificity and accuracy, and may therefore be recommended as a method for diagnosing PTB.  相似文献   
77.
Analysis of root canal treated primary incisor after trauma: two year outcomes     
Tannure PN  Fidalgo TK  Barcelos R  Primo LG  Maia LC 《The Journal of clinical pediatric dentistry》2012,36(3):257-262
  相似文献   
78.
Elimination of malaria in country Georgia     
Kandelaki G  Butsashvili M  Kalandadze I  Iosava M  Avaliani N  Imnadze P 《Acta tropica》2012,123(1):47-48
Malaria is well known in Georgia since ancient times, causing national disasters with associated significant mortality and economic losses. By 1970 Georgia managed to reach complete and sustained elimination of the disease as a result of comprehensive anti-malaria measures undertaken in the country. However from the mid-1990s, economic collapse following disintegration of Soviet Union causing breakdown of important public health networks including anti-malaria preventive and control infrastructure resulted in gradual increase of malaria cases in the country with a peak of 437 and 474 cases in 2001 and 2002, respectively. From 2000 two major anti-malaria efforts were carried out by National Center for Disease Control and Public Health, WHO and Global Fund to Fight AIDS, tuberculosis and malaria and as result of comprehensive and collaborative work in 2010 the level of zero cases of local mosquito-borne malaria transmission was achieved and the country entered the elimination phase.  相似文献   
79.
Left atrial metastases of poorly differentiated thyroid carcinoma diagnosed by echocardiography and magnetic resonance imaging--case report and review of literature     
Bertoldi EG  Severo MD  Scheffel RS  Foppa M  de Azevedo MJ  Maia AL 《Echocardiography (Mount Kisco, N.Y.)》2012,29(2):E30-E33
Intracardiac metastases of thyroid carcinoma are a rare event. Their incidence is low in large autopsy series, and antemortem diagnosis is even less common. We present the case of a woman with advanced poorly differentiated thyroid carcinoma who had extensive intracardiac metastases. This case highlights the usefulness of echocardiography and magnetic resonance imaging in the diagnosis and differential diagnosis of cardiac metastases.  相似文献   
80.
Pituitary deficiency after aneurysmal subarachnoid hemorrhage     
Julio Leonardo Barbosa Pereira  Lucas Alverne Freitas de Albuquerque  Marcos Dellaretti  Gervásio Teles Cardoso de Carvalho  Gerival Vieira Jr  Vitor Michelstaedter Brochado  Austen Venancio Drummond  Joyce Espeschit de Morais  Leticia Maia Ferreira  Paulo Augusto Carvalho Miranda  Atos Alves de Sousa 《Clinics (S?o Paulo, Brazil)》2013,68(6):745-749

OBJECTIVE:

Aneurysmal subarachnoid hemorrhage puts patients at high risk for the development of pituitary insufficiency. We evaluated the incidence of pituitary dysfunction in these patients and its correlation with clinical outcome.

METHODS:

Pituitary function was tested in 66 consecutive patients in the first 15 days after aneurysmal subarachnoid hemorrhage. The following were measured in all patients: thyroid-stimulating hormone, free thyroxine, triiodothyronine, luteinizing hormone, follicle-stimulating hormone, total testosterone (in males), estradiol (in females), prolactin, serum cortisol, plasma adrenocorticotropic hormone, growth hormone and insulin growth factor.

RESULTS:

The endocrine assessment was made at a mean of 7.4 days (standard deviation ±6.6) after subarachnoid hemorrhage. Forty-four (66.7%) female and 22 (33.3%) male patients were evaluated. Thirty-nine patients (59.1%) had some type of pituitary dysfunction. Follicle-stimulating hormone/luteinizing hormone deficiency was the most frequent disorder (34.8%), followed by growth hormone/insulin growth factor (28.7%), adrenocorticotropic hormone (18.1%) and thyroid-stimulating hormone (9%). Seventeen (25.7%) patients showed deficiencies in more than one axis. A greater incidence of hormone deficiency was observed in patients with a Glasgow Coma Scale score ≤13 (t test, p = 0.008), Hunt-Hess grade ≥4 (t test, p<0.001), or Fisher grade 4 (t test, p = 0.039). Hormone deficiency was not significantly associated (p>0.05) with increased hospitalization or clinical outcome.

CONCLUSION:

Pituitary dysfunction was identified in a substantial portion of patients with previous aneurysmal subarachnoid hemorrhage, but no association was found between this dysfunction and poor clinical outcome.  相似文献   
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