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1.
Phys Rev Lett ; 132(15): 151001, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38682982

RESUMO

We report on a measurement of astrophysical tau neutrinos with 9.7 yr of IceCube data. Using convolutional neural networks trained on images derived from simulated events, seven candidate ν_{τ} events were found with visible energies ranging from roughly 20 TeV to 1 PeV and a median expected parent ν_{τ} energy of about 200 TeV. Considering backgrounds from astrophysical and atmospheric neutrinos, and muons from π^{±}/K^{±} decays in atmospheric air showers, we obtain a total estimated background of about 0.5 events, dominated by non-ν_{τ} astrophysical neutrinos. Thus, we rule out the absence of astrophysical ν_{τ} at the 5σ level. The measured astrophysical ν_{τ} flux is consistent with expectations based on previously published IceCube astrophysical neutrino flux measurements and neutrino oscillations.

2.
Science ; 380(6652): 1338-1343, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37384687

RESUMO

The origin of high-energy cosmic rays, atomic nuclei that continuously impact Earth's atmosphere, is unknown. Because of deflection by interstellar magnetic fields, cosmic rays produced within the Milky Way arrive at Earth from random directions. However, cosmic rays interact with matter near their sources and during propagation, which produces high-energy neutrinos. We searched for neutrino emission using machine learning techniques applied to 10 years of data from the IceCube Neutrino Observatory. By comparing diffuse emission models to a background-only hypothesis, we identified neutrino emission from the Galactic plane at the 4.5σ level of significance. The signal is consistent with diffuse emission of neutrinos from the Milky Way but could also arise from a population of unresolved point sources.

3.
Science ; 378(6619): 538-543, 2022 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-36378962

RESUMO

A supermassive black hole, obscured by cosmic dust, powers the nearby active galaxy NGC 1068. Neutrinos, which rarely interact with matter, could provide information on the galaxy's active core. We searched for neutrino emission from astrophysical objects using data recorded with the IceCube neutrino detector between 2011 and 2020. The positions of 110 known gamma-ray sources were individually searched for neutrino detections above atmospheric and cosmic backgrounds. We found that NGC 1068 has an excess of [Formula: see text] neutrinos at tera-electron volt energies, with a global significance of 4.2σ, which we interpret as associated with the active galaxy. The flux of high-energy neutrinos that we measured from NGC 1068 is more than an order of magnitude higher than the upper limit on emissions of tera-electron volt gamma rays from this source.

4.
Phys Rev Lett ; 129(15): 151801, 2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36269964

RESUMO

We present a search for an unstable sterile neutrino by looking for a resonant signal in eight years of atmospheric ν_{µ} data collected from 2011 to 2019 at the IceCube Neutrino Observatory. Both the (stable) three-neutrino and the 3+1 sterile neutrino models are disfavored relative to the unstable sterile neutrino model, though with p values of 2.8% and 0.81%, respectively, we do not observe evidence for 3+1 neutrinos with neutrino decay. The best-fit parameters for the sterile neutrino with decay model from this study are Δm_{41}^{2}=6.7_{-2.5}^{+3.9} eV^{2}, sin^{2}2θ_{24}=0.33_{-0.17}^{+0.20}, and g^{2}=2.5π±1.5π, where g is the decay-mediating coupling. The preferred regions of the 3+1+decay model from short-baseline oscillation searches are excluded at 90% C.L.

5.
Phys Rev Lett ; 129(1): 011804, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35841552

RESUMO

We report a search for nonstandard neutrino interactions (NSI) using eight years of TeV-scale atmospheric muon neutrino data from the IceCube Neutrino Observatory. By reconstructing incident energies and zenith angles for atmospheric neutrino events, this analysis presents unified confidence intervals for the NSI parameter ε_{µτ}. The best-fit value is consistent with no NSI at a p value of 25.2%. With a 90% confidence interval of -0.0041≤ε_{µτ}≤0.0031 along the real axis and similar strength in the complex plane, this result is the strongest constraint on any NSI parameter from any oscillation channel to date.

6.
Helminthologia ; 59(1): 1-17, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35601761

RESUMO

Cystic echinococcosis is speculated to exert several immune-evasion strategies involving autoimmune-phenomena. We evaluated the hypothesizes that the prevalence of autoantibodies increases in the sera of CE patients that may evidence the association between the parasite and autoimmune diseases. Sera from 63 subjects at distinct types of CE cyst fertility were investigated for antinuclear antibodies (ANA), and anti-CCP antibodies. Plasma levels and cellular production of IL-17A cytokine were specifically defined as being assumed to prime for autoimmunity. Healthy-controls were age and gender-matched to test sera. ANA expressions inside the surgically removed metacestode and adventitial layer were also assayed. Out of 63 patients, 35 % had fertile highly viable cysts (group-1), 41 % had fertile low viable cysts (group-2) and 24 % had non-fertile cysts (group-3). A four-fold increase in ANA sera-levels was detected in group-1 compared with their controls (p-value 0.001) while anti-CCP levels were of insignificant differences. In group-2 and group-3, no significant differences were detected between ANA and anti-CCP sera-levels in CE patients and their controls. IL-17A sera-levels in group-1 and group- 2 were significantly higher than their healthy-controls while being of insignificant differences in group-3, p-value= 0.300. No association was detected between sera-levels of IL-17A and ANA as well as anti-CCP antibodies. Interestingly, relative IL-17A cellular expression associated positive ANA deposition in the parasite cells and adventitial layer. Collectively, based on the parasite fertility, IL-17A and ANA seemed to be involved in the host immune defenses against CE. There is no association between CE and anti-CCP antibodies.

7.
Phys Rev Lett ; 128(5): 051101, 2022 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-35179913

RESUMO

We present an all-sky 90% confidence level upper limit on the cosmic flux of relativistic magnetic monopoles using 2886 days of IceCube data. The analysis was optimized for monopole speeds between 0.750c and 0.995c, without any explicit restriction on the monopole mass. We constrain the flux of relativistic cosmic magnetic monopoles to a level below 2.0×10^{-19} cm^{-2} s^{-1} sr^{-1} over the majority of the targeted speed range. This result constitutes the most strict upper limit to date for magnetic monopoles with ß≳0.8 and up to ß∼0.995 and fills the gap between existing limits on the cosmic flux of nonrelativistic and ultrarelativistic magnetic monopoles.

8.
Trop Biomed ; 39(1): 36-46, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35225298

RESUMO

The present study evaluated the antiparasitic effect of curcumin extract on Schistosoma mansoni in Swiss albino mice. The experimental design included four groups of S. mansoni - infected mice; without treatment (controls), curcumin-treated, Praziquantel (PZQ)-treated, and PZQ +curcumin treated mice. The results showed that curcumin improved ISHAK confluent necrosis score up to zero. PZQ +curcumin showed a significant reduction in portal inflammation. Both activity and fibrosis demonstrated lower scores in all treated groups, however, PZQ revealed a marked increase in confluent necrosis and interface hepatitis. Besides, the lobular inflammation revealed worsening in the overall ISHAK score in all treated groups compared with the control. Few periocular granulomas were recovered by PZQ +curcumin treatment at day 35 post-treatment (6±1.2), P-value <0.05. Curcumin revealed a mild reduction (60±7.376). Curcumin-treated groups, with and without PZQ, resulted in higher significant Immunoreactivity score (IRS) for Bcl-2-associated X (BAX) and lower Interleukine- 17A (IL-17A), and Human epidermal growth factor (EGF), compared to the control. However, PZQ revealed a lower mean IRS value in BAX, higher IL-17A and EGF in the periovulatory granuloma. It was concluded that PZQ +curcumin treatment had a potent synergistic outcome through lessening the number of granulomas, the inflammatory events, and the expression of EGF, and amelioration of apoptosis in the periovulatory granulomas if compared with either PZQ or curcumin alone.


Assuntos
Anti-Helmínticos , Curcumina , Esquistossomose mansoni , Animais , Anti-Helmínticos/uso terapêutico , Curcumina/uso terapêutico , Fator de Crescimento Epidérmico/uso terapêutico , Granuloma/tratamento farmacológico , Inflamação/tratamento farmacológico , Interleucina-17 , Camundongos , Necrose/tratamento farmacológico , Praziquantel/uso terapêutico , Esquistossomose mansoni/tratamento farmacológico , Proteína X Associada a bcl-2
9.
Tropical Biomedicine ; : 36-46, 2022.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-936395

RESUMO

@#The present study evaluated the antiparasitic effect of curcumin extract on Schistosoma mansoni in Swiss albino mice. The experimental design included four groups of S. mansoniinfected mice; without treatment (controls), curcumin-treated, Praziquantel (PZQ)-treated, and PZQ +curcumin treated mice. The results showed that curcumin improved ISHAK confluent necrosis score up to zero. PZQ +curcumin showed a significant reduction in portal inflammation. Both activity and fibrosis demonstrated lower scores in all treated groups, however, PZQ revealed a marked increase in confluent necrosis and interface hepatitis. Besides, the lobular inflammation revealed worsening in the overall ISHAK score in all treated groups compared with the control. Few periocular granulomas were recovered by PZQ +curcumin treatment at day 35 post-treatment (6±1.2), P-value <0.05. Curcumin revealed a mild reduction (60±7.376). Curcumin-treated groups, with and without PZQ, resulted in higher significant Immunoreactivity score (IRS) for Bcl-2-associated X (BAX) and lower Interleukine17A (IL-17A), and Human epidermal growth factor (EGF), compared to the control. However, PZQ revealed a lower mean IRS value in BAX, higher IL-17A and EGF in the periovulatory granuloma. It was concluded that PZQ +curcumin treatment had a potent synergistic outcome through lessening the number of granulomas, the inflammatory events, and the expression of EGF, and amelioration of apoptosis in the periovulatory granulomas if compared with either PZQ or curcumin alone.

10.
Trop Biomed ; 38(2): 53-62, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33973573

RESUMO

BACKGROUND: toxoplasmosis is a cosmopolitan protozoan disease with a wide range of neuropathology. Recent studies identified its potential association with several mental disorders e.g. schizophrenia dependable on apoptosis in their pathogenesis. We investigated value of toxoplasmosis to induce apoptosis of the neuronal cells. METHODS: per-orally infected C57BL/6 mice with 15-20 cysts of the avirulent T. gondii Beverly strain at 9-11 weeks of age were examined 12 weeks later during parasite establishment. Distributions of the parasite's cysts and the histopathological lesions in the brains were analyzed using Image J software. Relative expression of TNF-α and iNOS of cell-mediated immunity (CMI), Bax (pro-apoptosis) and Bcl-2 (anti-apoptosis) were all assessed using immunohistochemistry. RESULTS: higher parasite burden was seen in the forebrain with p value <= 0.05. Dramatically increased TNF-α, iNOS, and Bax expressions with Bax/Bcl-2 ratio 2.42:0.52 were reported (p value <= 0.05). The significant correlation between Bax data and different CMI biomarkers including TNF-α and i-NOS was evaluated. Interestingly, no significant correlation was seen between TNF-α, iNOS, Bax and Bcl-2 expressions and location of the parasite. However, Bax/Bcl-2 ratio was statistically correlated with CMI biomarkers and whole sample mean parasite burden, p value <= 0.05. CONCLUSION: Chronic toxoplasmosis exhibits an immense pro-apoptotic signal on the cerebral tissues of experimental mice.


Assuntos
Apoptose , Toxoplasmose Cerebral , Animais , Modelos Animais de Doenças , Imunidade Celular , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico Sintase Tipo II/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Toxoplasma , Toxoplasmose Cerebral/imunologia , Toxoplasmose Cerebral/patologia , Fator de Necrose Tumoral alfa/metabolismo , Proteína X Associada a bcl-2/metabolismo
11.
Tropical Biomedicine ; : 53-62, 2021.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-904534

RESUMO

@#Background: toxoplasmosis is a cosmopolitan protozoan disease with a wide range of neuropathology. Recent studies identified its potential association with several mental disorders e.g. schizophrenia dependable on apoptosis in their pathogenesis. We investigated value of toxoplasmosis to induce apoptosis of the neuronal cells. Methods: per-orally infected C57BL/6 mice with 15-20 cysts of the avirulent T. gondii Beverly strain at 9-11 weeks of age were examined 12 weeks later during parasite establishment. Distributions of the parasite’s cysts and the histopathological lesions in the brains were analyzed using Image J software. Relative expression of TNF-α and iNOS of cell-mediated immunity (CMI), Bax (pro-apoptosis) and Bcl-2 (anti-apoptosis) were all assessed using immunohistochemistry. Results: higher parasite burden was seen in the forebrain with p value < 0.05. Dramatically increased TNF-α, iNOS, and Bax expressions with Bax/Bcl-2 ratio 2.42:0.52 were reported (p value < 0.05). The significant correlation between Bax data and different CMI biomarkers including TNF-α and i-NOS was evaluated. Interestingly, no significant correlation was seen between TNF-α, iNOS, Bax and Bcl-2 expressions and location of the parasite. However, Bax/Bcl-2 ratio was statistically correlated with CMI biomarkers and whole sample mean parasite burden, p value < 0.05. Conclusion: Chronic toxoplasmosis exhibits an immense pro-apoptotic signal on the cerebral tissues of experimental mice.

12.
Phys Rev Lett ; 125(14): 141801, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33064514

RESUMO

The results of a 3+1 sterile neutrino search using eight years of data from the IceCube Neutrino Observatory are presented. A total of 305 735 muon neutrino events are analyzed in reconstructed energy-zenith space to test for signatures of a matter-enhanced oscillation that would occur given a sterile neutrino state with a mass-squared differences between 0.01 and 100 eV^{2}. The best-fit point is found to be at sin^{2}(2θ_{24})=0.10 and Δm_{41}^{2}=4.5 eV^{2}, which is consistent with the no sterile neutrino hypothesis with a p value of 8.0%.

13.
Med J Malaysia ; 64(2): 170-1, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20058582

RESUMO

Timely identification of specific injuries in a polytrauma case is of paramount importance in order to reduce morbidity and mortality. Unfortunately, some of these injuries are subtle and can be missed on initial primary and secondary assessments. In this paper, we report one such injury in a case of a 16-year old motorcyclist who complained of abdominal pain over the right lumbar region after the motorcycle handlebar hit his abdomen. Although initial assessment was uneventful, he was subsequently diagnosed to have a traumatic abdominal wall herniation on abdominal computed tomography after more than 24 hours of observation in the ward.


Assuntos
Traumatismos Abdominais/complicações , Acidentes de Trânsito , Hérnia Abdominal/etiologia , Motocicletas , Traumatismos Abdominais/diagnóstico por imagem , Adolescente , Hérnia Abdominal/diagnóstico por imagem , Humanos , Masculino , Tomografia Computadorizada por Raios X
14.
Scand J Infect Dis ; 32(1): 47-50, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10716077

RESUMO

In a retrospective study, 45 clinical isolates of non-tuberculous mycobacteria were identified to the species level by biochemical profile, gas liquid chromatography and partial sequence analysis of 16S rRNA, and were found to represent 13 different species. The results of sequence analysis showed 100% identity with conventional tests for 34 isolates (76%) and could identify species such as M. bohemicum which are difficult to characterise with conventional methods. Most of the discrepant results for the remaining 11 isolates resulted in species of the same group of mycobacteria. Based on these findings. we concluded that direct sequence analysis of amplified 16S rRNA gene is a promising rapid and accurate method for species determination of non-tuberculous mycobacteria.


Assuntos
Micobactérias não Tuberculosas/genética , RNA Bacteriano/análise , RNA Ribossômico 16S/análise , Técnicas de Tipagem Bacteriana , Cromatografia Gasosa , Genótipo , Humanos , Micobactérias não Tuberculosas/química , Micobactérias não Tuberculosas/classificação , Reação em Cadeia da Polimerase , Estudos Retrospectivos , Análise de Sequência de RNA/classificação , Especificidade da Espécie
16.
Am Fam Physician ; 53(5): 1691-7, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8623695

RESUMO

Necrotizing fasciitis is a life-threatening, invasive soft-tissue infection that is characterized by widespread, rapidly developing necrosis of the subcutaneous tissue and fascia. It is more likely to occur in patients with a compromised immune system. In type I necrotizing fasciitis, anaerobes and gram-negative bacteria are predominant; in the type II form, the bacterial etiology is group A beta-hemolytic streptococci. The diagnosis must be made on the basis of clinical grounds and is characterized by rapidly developing, painful erythema that progresses to bullous formation and gangrenous necrosis.


Assuntos
Fasciite Necrosante , Adulto , Terapia Combinada , Diagnóstico Diferencial , Fasciite Necrosante/diagnóstico , Fasciite Necrosante/microbiologia , Fasciite Necrosante/fisiopatologia , Fasciite Necrosante/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco
17.
Clin Ther ; 17(4): 701-7, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8565033

RESUMO

The efficacy, safety, and tolerability of a 5-day, once-daily course of azithromycin were assessed in patients with acute sinusitis. Patients received two 250-mg capsules of azithromycin on day 1 and one 250-mg capsule on days 2 through 5. Of 102 clinically assessable patients, 27 (26.5%) were cured and 69 (67.6%) were improved on days 5 to 7. At days 12 to 16, 88 (86.3%) had a favorable clinical response. A total of 64 patients experienced adverse events; in all but two patients, adverse events were of mild or moderate severity. Thus azithromycin given once daily for 5 days was an effective treatment for patients with acute sinusitis.


Assuntos
Antibacterianos/uso terapêutico , Azitromicina/uso terapêutico , Sinusite/tratamento farmacológico , Doença Aguda , Adulto , Antibacterianos/efeitos adversos , Azitromicina/efeitos adversos , Feminino , Humanos , Masculino , Resultado do Tratamento
18.
Postgrad Med ; 95(4): 46-52, 56, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8121859

RESUMO

Tuberculosis is on the increase around the globe. Practicing physicians must be vigilant in identifying persons at risk and those who are infected with tubercle bacilli so isoniazid prophylaxis can be promptly instituted. The tuberculin skin test is a simple, inexpensive, and sensitive method of diagnosing infection; it should be used routinely and not reserved for high-risk patients. The Centers for Disease Control and Prevention has issued new guidelines for interpreting results depending on the size of induration and presence of risk factors.


Assuntos
Teste Tuberculínico , Reações Falso-Negativas , Reações Falso-Positivas , Humanos , Estados Unidos
19.
Postgrad Med ; 92(3): 161-8, 1992 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-1518752

RESUMO

Malaria is largely preventable, so travelers should be taught general protective measures and given appropriate chemoprophylaxis before they leave on their trip. Chloroquine phosphate (Aralen) is still the drug of choice in locations where malaria remains chloroquine-sensitive. However, chloroquine-resistant areas infested with Plasmodium falciparum are becoming more numerous. In such areas, mefloquine hydrochloride (Lariam), doxycycline, or proguanil (Paludrine) (obtainable outside the United States) may be used. A single dose of pyrimethamine-sulfadoxine (Fansidar) may be used to treat presumptive malarial infection if medical care is not immediately available. For prevention of relapse of Plasmodium vivax and Plasmodium ovale infection, primaquine phosphate is recommended for the final 2 weeks of chemoprophylaxis on return from a malarious area.


Assuntos
Malária/prevenção & controle , Viagem , Antimaláricos/administração & dosagem , Antimaláricos/efeitos adversos , Antimaláricos/uso terapêutico , Protocolos Clínicos/normas , Resistência a Medicamentos , Humanos , Malária/tratamento farmacológico , Malária/epidemiologia , Prevenção Primária/métodos , Prevenção Primária/normas , Vacinas Protozoárias/normas , Recidiva , Fatores de Risco
20.
Postgrad Med ; 88(6): 107-14, 117-9, 122-4, 1990 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-2235776

RESUMO

Tuberculosis has been on the increase in recent years, so physicians need to be aware of it once again. Very effective drugs are available to treat the disease. Pharmacokinetics, dosing schedule, and adverse reactions of each anti-tuberculous agent need to be considered. A short (6-month) course of therapy is now recommended: Isoniazid, rifampin (Rifadin, Rimactane), and pyrazinamide are given for the initial 2 months, followed by isoniazid and rifampin for 4 months. If drug resistance is a factor, a fourth drug is added to the initial regimen, and therapy may have to be extended. Chemoprophylaxis with isoniazid is very important to reduce the incidence of tuberculosis. It should be given to all high-risk persons.


Assuntos
Antituberculosos/administração & dosagem , Tuberculose Pulmonar/tratamento farmacológico , Antituberculosos/efeitos adversos , Antituberculosos/uso terapêutico , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Esquema de Medicação , Interações Medicamentosas , Humanos , Risco , Tuberculose Pulmonar/epidemiologia , Tuberculose Pulmonar/etiologia
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