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1.
Cell Tissue Res ; 395(2): 159-169, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38082139

RESUMO

Prosaposin (PSAP), a potent neurotrophic factor, is found in neuronal and non-neuronal tissues and various biological fluids. Neuropathological conditions often alter PSAP production in neural tissues. However, little is known about its alterations in non-neural tissues, particularly in the salivary glands, which are natural reservoirs of various neurotrophic factors. In this study, we explored whether neurotoxic stimulation by kainic acid (KA), a glutamate analog, altered PSAP levels in the salivary system of rats. The results revealed that KA injection did not alter total saliva production. However, KA-induced neurotoxic stimulation significantly increased the PSAP level in the secreted saliva but decreased it in the serum. In addition, KA-induced elevated immunoreactivities of PSAP and its receptors have been observed in the granular convoluted tubule (GCT) cells of the submandibular gland (SMG), a major salivary secretory organ. Indeed, a large number of PSAP-expressing immunogold particles were observed in the secretory granules of the SMG. Furthermore, KA-induced overexpression of PSAP was co-localized with secretogranin in secretory acini (mostly in GCT cells) and the ductal system of the SMG, suggesting the release of excess PSAP from the salivary glands into the oral cavity. In conclusion, the salivary system produces more PSAP during neurotoxic conditions, which may play a protective role in maintaining the secretory function of the salivary glands and may work in distant organs.


Assuntos
Glândulas Salivares , Saposinas , Ratos , Animais , Glândula Submandibular , Saliva , Proteínas de Transporte
2.
Prostaglandins Other Lipid Mediat ; 172: 106818, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38340978

RESUMO

Platelet-activating factor (PAF) plays a significant role in several leucocyte functions, including platelet aggregation and inflammation. Additionally, PAF has a role in the behavioral and physiological changes in mammals. However, the effect of PAF has not been well studied in birds. Therefore, the study aimed to determine if PAF affects feeding behavior, voluntary activity, cloacal temperature, and feed passage through the digestive tract in chicks (Gallus gallus). We also studied the involvement of PAF in the innate immune system induced by lipopolysaccharide (LPS), a cell wall component of gram-negative bacteria. Both intraperitoneal (IP) and intracerebroventricular (ICV) injections of PAF significantly decreased food intake. IP injection of PAF significantly decreased voluntary activity and slowed the feed passage from the crop, whereas ICV injection had no effect. Conversely, ICV injection of PAF significantly increased the cloacal temperature, but IP injection had no effect. The IP injection of LPS significantly reduced the mRNA expression of lysophosphatidylcholine acyltransferase 2, an enzyme responsible for PAF production in the heart and pancreas. On the other hand, LPS significantly increased the mRNA expression of the PAF receptor in the peripheral organs. The present study shows that PAF influences behavioral and physiological responses and is related to the response against bacterial infections in chicks.


Assuntos
Temperatura Corporal , Galinhas , Cloaca , Papo das Aves , Ingestão de Alimentos , Fator de Ativação de Plaquetas , Animais , Masculino , Temperatura Corporal/efeitos dos fármacos , Cloaca/efeitos dos fármacos , Cloaca/fisiologia , Papo das Aves/efeitos dos fármacos , Papo das Aves/metabolismo , Ingestão de Alimentos/efeitos dos fármacos , Comportamento Alimentar/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Fator de Ativação de Plaquetas/farmacologia , Fator de Ativação de Plaquetas/metabolismo , Glicoproteínas da Membrana de Plaquetas/genética , Glicoproteínas da Membrana de Plaquetas/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/genética
3.
BMC Infect Dis ; 24(1): 59, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38191305

RESUMO

BACKGROUND: Yersinia enterocolitica is a gram-negative zoonotic bacterial pathogen that is typically transmitted via the fecal-oral route. The most common clinical manifestation of a Y. enterocolitica infection is self-limited gastroenteritis. Although various extraintestinal manifestations of Y. enterocolitica infection have been reported, there are no reports of thyroid abscesses. CASE PRESENTATION: An 89-year-old Japanese man with follicular adenoma of the left thyroid gland was admitted to our hospital with a 2-day history of fever and left neck pain. Laboratory tests revealed low levels of thyroid stimulating hormone and elevated levels of free thyroxine 4. Contrast-enhanced computed tomography showed low-attenuation areas with peripheral enhancement in the left thyroid gland. He was diagnosed with thyroid abscess and thyrotoxicosis, and treatment with intravenous piperacillin-tazobactam was initiated after collecting blood, drainage fluid, and stool samples. The isolated Gram-negative rod bacteria from blood and drainage fluid cultures was confirmed to be Y. enterocolitica. He was diagnosed with thyroid abscess and thyrotoxicosis due to be Y. enterocolitica subsp. palearctica. The piperacillin-tazobactam was replaced with levofloxacin. CONCLUSION: We report a novel case of a thyroid abscess associated with thyrotoxicosis caused by Y. enterocolitica subsp. palearctica in a patient with a follicular thyroid adenoma.


Assuntos
Adenoma , Neoplasias da Glândula Tireoide , Tireotoxicose , Yersinia enterocolitica , Masculino , Humanos , Idoso de 80 Anos ou mais , Abscesso/diagnóstico , Tireotoxicose/complicações , Tireotoxicose/diagnóstico , Piperacilina , Tazobactam
4.
J Infect Chemother ; 30(2): 169-171, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37734592

RESUMO

Children infected with SARS-CoV-2 are often asymptomatic or have mild symptoms. The studies on the seroprevalence kinetics of SARS-CoV-2 antibodies in children are limited. We conducted a cross-sectional survey of the positive rate of the SARS-CoV-2 IgG in pediatric patients without suspected COVID-19 infection between January 2007 and March 2022. We defined the serum samples from the pre-pandemic and pandemic groups (1st-6th waves). Totally, 2557 samples were collected and no samples from the pre-pandemic group or the 1st-4th waves were positive for IgG. There were 4/661 and 16/373 positives at the 5th and 6th waves, respectively. At the 5th wave, the prevalence of IgG was 1.3% in children aged 1-4 years. At the 6th wave, in children <1 year of age, the prevalence was 4.0%, and 2.4%, 5.3%, 5.2% and 10% in age groups 1-4, 5-9, 10-14 and 15-18 years, respectively. In conclusions, the pre-pandemic samples were negative, and the IgG positivity increased during the later period of the pandemic.


Assuntos
COVID-19 , Humanos , Criança , Lactente , COVID-19/epidemiologia , SARS-CoV-2 , Japão/epidemiologia , Pandemias , Estudos Transversais , Estudos Soroepidemiológicos , Hospitais , Anticorpos Antivirais , Imunoglobulina G
5.
Artigo em Inglês | MEDLINE | ID: mdl-38147959

RESUMO

Zymosan is a fungi-derived pathogen-associated molecular pattern. It activates the immune system and induces the reduction of feed passage rate in the gastrointestinal tract of vertebrates including birds. However, the mechanism mediating the zymosan-induced inhibition of feed passage in the gastrointestinal tract remains unknown. Since the medulla oblongata regulates the digestive function, it is plausible that the medulla oblongata is involved in the zymosan-induced inhibition of feed passage. The present study was performed to identify the genes that were affected by zymosan within the medulla oblongata of chicks (Gallus gallus) using an RNA sequencing approach. We found that mRNAs of several bioactive molecules including neuropeptide Y (NPY) were increased with an intraperitoneal (IP) injection of zymosan. The increase of mRNA expression of NPY in the medulla oblongata was also observed after the IP injection of lipopolysaccharide, derived from gram-negative bacteria. These results suggest that medullary NPY is associated with physiological changes during fungal and bacterial infection. Furthermore, we found that intracerebroventricular injection of NPY and its receptor agonists reduced the feed passage from the crop. Additionally, the injection of NPY reduced the feed passage from the proventriculus to lower digestive tract. NPY also suppressed the activity of duodenal activities of amylase and trypsin. The present study suggests that fungi- and bacteria-induced activation of the immune system may activate the NPY neurons in the medulla oblongata and thereby reduce the digestive function in chicks.


Assuntos
Lipopolissacarídeos , Neuropeptídeo Y , Animais , Neuropeptídeo Y/genética , Neuropeptídeo Y/metabolismo , Lipopolissacarídeos/farmacologia , Zimosan/farmacologia , Galinhas/metabolismo , Bulbo/metabolismo , Trato Gastrointestinal/metabolismo
6.
Emerg Infect Dis ; 29(10): 2171-2172, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37735785

RESUMO

We report a case of Bacillus subtilis variant natto bacteremia from a gastrointestinal perforation in a patient who ingested natto. Genotypic methods showed the bacteria in a blood sample and the ingested natto were the same strains. Older or immunocompromised patients could be at risk for bacteremia from ingesting natto.


Assuntos
Bacteriemia , Alimentos de Soja , Humanos , Japão , Bacillus subtilis , Bacteriemia/diagnóstico , Ingestão de Alimentos
7.
Gen Comp Endocrinol ; 328: 114101, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35940317

RESUMO

Bradykinin is a well-studied bioactive peptide associated with several physiological functions, including vasodilation and inflammation, in mammals. However, its avian homolog, ornithokinin, has received less research attention in birds. Therefore this study aimed to investigate the effect of intraperitoneal (IP) and intracerebroventricular (ICV) injections of ornithokinin on feeding behavior, cloacal temperature, voluntary activity, crop emptying rate, and blood constituents in chicks (Gallus gallus). We also investigated the effect of lipopolysaccharide (LPS), a cell wall component of gram-negative bacteria, on ornithokinin-associated gene expression was also investigated to determine whether activation of the ornithokinin system is induced by bacterial infection. Both IP and ICV injections of ornithokinin significantly decreased feed intake, cloacal temperature, voluntary activity, and crop emptying rate in chicks, but they did not affect the plasma concentration of corticosterone. Additionally, LPS significantly increased the expression of ornithokinin B2 receptor mRNA in several organs. Hence, ornithokinin is associated with a range of physiological responses in chicks and may be related to their response to bacterial infection.


Assuntos
Galinhas , Corticosterona , Animais , Bradicinina/análogos & derivados , Bradicinina/farmacologia , Galinhas/fisiologia , Ingestão de Alimentos , Comportamento Alimentar , Injeções Intraventriculares , Lipopolissacarídeos/farmacologia , Mamíferos , RNA Mensageiro , Temperatura
8.
Artigo em Inglês | MEDLINE | ID: mdl-35918017

RESUMO

Infections frequently accompany with non-specific symptoms such as anorexia and hyperthermia. In addition, there may be unpleasant sensations such as visceral discomfort during infection. Lipopolysaccharide (LPS), a Gram-negative bacteria cell wall component, is known to induce the unpleasant sensation of conditioned taste aversion in mammals. However, the relationship between unpleasant sensations and changes in behavior and physiological conditions has not been investigated extensively in birds. Lithium chloride (LiCl) is a compound that induces unpleasant sensations, including visceral discomfort, although its effects on behavior and physiological conditions have also not been investigated extensively in birds. Thus, the present study was aimed to investigate the effect of an intraperitoneal (IP) injection of LiCl on conditioned visual aversion, food intake, cloacal temperature, voluntary activity, crop-emptying rate, and blood constituents in chicks (Gallus gallus). We also examined the effect of IP injections of LPS and zymosan, a cell wall component of fungus, on conditioned visual aversion formation. First, IP injection of LiCl was confirmed to induce conditioned visual aversion in chicks. An IP injection of LiCl significantly decreased food intake, voluntary activity, and crop-emptying rate but did not affect the temperature. In addition, the injection of LiCl significantly increased plasma corticosterone concentration, indicating that LiCl serves as a stressor in chicks. Finally, IP injections of LPS and zymosan were found to induce conditioned visual aversion in chicks. Collectively, these results suggest that LiCl induces conditioned aversion, anorexia, hypoactivity, and inhibition of crop-emptying in chicks. In addition, LPS and zymosan would induce unpleasant sensations in chicks.


Assuntos
Galinhas , Cloreto de Lítio , Animais , Anorexia , Galinhas/fisiologia , Ingestão de Alimentos , Lipopolissacarídeos/farmacologia , Lítio/farmacologia , Cloreto de Lítio/farmacologia , Mamíferos , Paladar , Temperatura , Zimosan/farmacologia
9.
Artigo em Inglês | MEDLINE | ID: mdl-35417747

RESUMO

Nitric oxide (NO) is a gaseous bioactive molecule associated with many physiological functions including vasodilation and neurotransmission. NO also plays an important role in immune responses during viral infections in mammals. However, there is a paucity of knowledge regarding the involvement of NO in viral infections in birds. Therefore, the purpose of the present study was to determine if intraperitoneal (IP) injection of poly I:C and R848 (resiquimod), which are analogues of virus component, affects NO production in chicks (Gallus gallus) as a bird model. The involvement of inducible NO synthase (iNOS) in poly I:C- and R848-induced anorexia and corticosterone release was also investigated. These virus analogues significantly increased plasma NO metabolites (NOx) concentrations. IP injection of poly I:C and R848 significantly increased iNOS mRNA expression in several organs including the liver. On the other hand, poly I:C and R848 significantly decreased mRNA expressions of endothelial NOS and neural NOS in several organs, indicating that induction of iNOS might be responsible for increased NOx levels in plasma. This finding was further confirmed by using a selective iNOS inhibitor, S-methylisothiourea sulfate (SMT), which abolished the poly I:C- and R848-induced increase in plasma NOx concentration. In addition, SMT partly attenuated the poly I:C- and R848-induced increase in plasma corticosterone concentration, suggesting that corticosterone release induced by these virus analogues may be partly mediated by iNOS. Collectively, the present results suggest that viral infections facilitate NO production by inducing iNOS. The liver would play an important role in the NO production because the response in iNOS mRNA expression to poly I:C and R848 was remarkable. The present results also suggest that NO is associated with corticosterone release in birds under viral infection.


Assuntos
Óxido Nítrico Sintase , Óxido Nítrico , Animais , Galinhas/metabolismo , Corticosterona , Mamíferos/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Poli I-C/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
10.
Cell Tissue Res ; 383(3): 1191-1202, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33242172

RESUMO

Prosaposin (PSAP) has two forms: a precursor and a secreted form. The secreted form has neurotrophic, myelinotrophic, and myotrophic properties. The precursor form is a precursor protein of saposins A-D. Although the distribution of PSAP in male reproductive organs is well known, its distribution in female reproductive organs, especially in the oviduct, is unclear. Immunoblots and immunohistochemistry of oviducts showed that oviductal tissues contain PSAP proteins, and a significant increase in PSAP was observed in the estrus-metestrus phase compared to the diestrus-proestrus phase in the ampulla. To identify PSAP trafficking in cells, double-immunostaining was performed with antibodies against PSAP in combination with sortilin, mannose 6 phosphate receptor (M6PR), or low-density lipoprotein receptor-related protein 1 (LRP1). PSAP and sortilin double-positive reactions were observed near the nuclei, as well as in the apical portion of microvillous epithelial cells, whereas these reactions were only observed near the nuclei of ciliated epithelial cells. PSAP and M6PR double-positive reactions were observed near the nuclei of microvillous and ciliated epithelial cells. PSAP and M6PR double-positive reactions were also observed in the apical portion of microvillous epithelial cells. PSAP and LRP1 double-positive reactions were observed in the plasma membrane and apical portion of both microvillous and ciliated epithelial cells. Immunoelectron staining revealed PSAP immunoreactive small vesicles with exocytotic features at the apical portion of microvillous epithelial cells. These findings suggest that PSAP is present in the oviductal epithelium and has a pivotal role during pregnancy in providing an optimal environment for gametes and/or sperm in the ampulla.


Assuntos
Células Epiteliais , Ciclo Estral/metabolismo , Tubas Uterinas , Receptor IGF Tipo 2/metabolismo , Saposinas/metabolismo , Animais , Membrana Celular/metabolismo , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Tubas Uterinas/citologia , Tubas Uterinas/metabolismo , Feminino , Gravidez , Ratos , Ratos Wistar
11.
IJID Reg ; 12: 100395, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39077761

RESUMO

Objectives: Dengue, a life-threatening disease caused by the mosquito-borne dengue virus, has become a severe problem in recent years in Bangladesh, a South Asian country. In this study, we have critically analyzed the factors contributing to the escalation of the dengue burden in recent years in Bangladesh and discussed the strategies for effective control. Design: This retrospective observational study analyzed the dengue data collected from the five most dengue-affected countries (Bangladesh, Brazil, Mexico, Peru, and the Philippines) from 2019 to 2023. Results: An increased number of dengue-related deaths has been recorded in Bangladesh since 2021. The year 2023 has witnessed a record high dengue-related deaths in Bangladesh, with cumulative deaths for the year surpassing all totals of the previous 23 years (2000-2022: 853 deaths vs 2023: 1705 deaths). Comparing the epidemiologic data of major dengue-endemic countries over the last 5 years, Bangladesh recorded higher dengue fatality rates consecutively for 3 years. Besides the environmental and viral host factors, which are also applicable to many other dengue-endemic countries, there is concern about the failures and mismanagement of authorities to manage dengue patients properly. Conclusion: This study provided evidence that Bangladesh recorded higher dengue fatality rates in recent years. By implementing multi-pronged proactive approaches that can ensure proper prevention programs and appropriate patient management, Bangladesh or similar other countries can significantly reduce the current dengue burden and the associated deaths.

12.
Vet Immunol Immunopathol ; 271: 110752, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38579442

RESUMO

Nitric oxide (NO) is gaseous bioactive molecule that is synthesized by NO synthase (NOS). Inducible NOS (iNOS) expression occurs in response to pathogenic challenges, resulting in the production of large amounts of NO. However, there is a lack of knowledge regarding neuronal NOS (nNOS) and endothelial NOS (eNOS) in birds during pathogenic challenge. Therefore, the present study was conducted to determine the influence of intraperitoneal (IP) injection of zymosan (cell wall component of yeast) and lipopolysaccharide (LPS, a cell wall component of gram-negative bacteria) on NOS expression in chicks (Gallus gallus). Furthermore, the effect of NOS inhibitors on the corresponding behavioral and physiological parameters was investigated. Zymosan and LPS injections induced iNOS mRNA expression in several organs. Zymosan had no effect on eNOS mRNA expression in the organs investigated, whereas LPS increased its expression in the pancreas. Zymosan and LPS decreased nNOS mRNA expression in the lung, heart, kidney, and pancreas. The decreased nNOS mRNA expression in pancreas was probably associated with the NO from iNOS provided that such effect was reproduced by IP injection of sodium nitroprusside, which is a NO donor. Furthermore, pancreatic nNOS mRNA expression decreased following subcutaneous injection of corticosterone. Furthermore, IP injections of a nonspecific NOS inhibitor, NG-nitro-L-arginine methyl ester, and an nNOS-specific inhibitor, 7-nitroindazole, resulted in the significant decreases in food intake, cloacal temperature, and feed passage via the digestive tract in chicks. Collectively, the current findings imply the decreased nNOS expression because of fungal and bacterial infections, which affects food intake, body temperature, and the digestive function in birds.


Assuntos
Galinhas , Lipopolissacarídeos , Óxido Nítrico Sintase Tipo I , Zimosan , Animais , Zimosan/farmacologia , Lipopolissacarídeos/farmacologia , Galinhas/imunologia , Óxido Nítrico Sintase Tipo I/genética , Óxido Nítrico Sintase Tipo I/metabolismo , Masculino , Indazóis/farmacologia , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo
13.
Am J Trop Med Hyg ; 111(2): 429-432, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-38889707

RESUMO

No specific treatment has been developed for severe fever with thrombocytopenia syndrome (SFTS). However, the prognosis can improve with early plasma exchange. Therefore, rapid and accurate detection of SFTS virus is important for diagnosis and prognosis. Direct real-time reverse transcription polymerase chain reaction (RT-PCR) testing is easier and more time-efficient than conventional real-time RT-PCR. Our study compared direct real-time RT-PCR efficiency without the RNA extraction and purification of conventional real-time RT-PCR. Samples were collected from 18 patients with SFTS and five without SFTS. A strong correlation (r = 0.774, 95% CI: 0.652-0.857, P <0.01) was found between conventional and direct real-time RT-PCR assays. Direct real-time RT-PCR showed 84.4% sensitivity and 92.0% specificity for viral detection. Direct real-time RT-PCR is an effective diagnostic tool for patients with acute phase SFTS, but further optimization is required for viral detection.


Assuntos
Phlebovirus , RNA Viral , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sensibilidade e Especificidade , Febre Grave com Síndrome de Trombocitopenia , Humanos , Febre Grave com Síndrome de Trombocitopenia/diagnóstico , Febre Grave com Síndrome de Trombocitopenia/virologia , Phlebovirus/genética , Phlebovirus/isolamento & purificação , RNA Viral/isolamento & purificação , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Adulto
14.
Infect Genet Evol ; 119: 105572, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38367678

RESUMO

This investigation delineates an exhaustive analysis of the clinical, immunological, and genomic landscapes of hepatitis B virus (HBV) infection across a cohort of 22 verified patients. The demographic analysis unveiled a pronounced male bias (77.27%), with patient ages spanning 20 to 85 years and durations of illness ranging from 10 days to 4 years. Predominant clinical manifestations included fever, fatigue, anorexia, abdominal discomfort, and arthralgia, alongside observed co-morbidities such as chronic renal disorders and hepatocellular carcinoma. Antigenic profiling of the HBV envelope proteins elucidated significant heterogeneity among the infected subjects, particularly highlighted by discordances in the detection capabilities of small and large HBsAg assays, suggesting antigenic diversity. Quantitative assessment of viral loads unveiled a broad spectrum, accompanied by atypical HBeAg reactivity patterns, challenging the reliability of existing serological markers. Correlative studies between viral burden and antigenicity of the envelope proteins unearthed phenomena indicative of diagnostic evasion. Notably, samples demonstrating robust viral replication were paradoxically undetectable by the large HBsAg ELISA kit, advocating for more sophisticated diagnostic methodologies. Genotypic examination of three HBV isolates classified them as genotype D (D2), with phylogenetic alignment to strains from various global origins. Mutational profiling identified pivotal mutations within the basic core promoter and preS2/S1 regions, associated with an augmented risk of hepatocellular carcinoma. Further, mutations discerned in the small HBsAg and RT/overlap regions were recognized as contributors to vaccine and/or diagnostic escape mechanisms. In summation, this scholarly discourse elucidates the intricate interplay of clinical presentations, antigenic diversity, and genomic attributes in HBV infection, accentuating the imperative for ongoing investigative endeavors to refine diagnostic and therapeutic modalities.


Assuntos
Carcinoma Hepatocelular , Hepatite B Crônica , Hepatite B , Neoplasias Hepáticas , Humanos , Masculino , Vírus da Hepatite B , Antígenos de Superfície da Hepatite B/genética , Bangladesh/epidemiologia , Filogenia , Reprodutibilidade dos Testes , Mutação , Genótipo , Variação Antigênica , Genômica , DNA Viral/genética
15.
Vaccines (Basel) ; 11(3)2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36992199

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has devastated the world with coronavirus disease 2019 (COVID-19), which has imparted a toll of at least 631 million reported cases with 6.57 million reported deaths. In order to handle this pandemic, vaccines against SARS-CoV-2 have been developed and billions of doses of various vaccines have been administered. In the meantime, several antiviral drugs and other treatment modalities have been developed to treat COVID-19 patients. At the end of the day, it seems that anti-SARS-CoV-2 vaccines and newly developed antiviral drugs may be improved based on various new developments. COVID-19 represents a virus-induced, immune-mediated pathological process. The severity of the disease is related to the nature and properties of the host immune responses. In addition, host immunity plays a dominant role in regulating the extent of COVID-19. The present reality regarding the role of anti-SARS-CoV-2 vaccines, persistence of SARS-CoV-2 infection even three years after the initiation of the pandemic, and divergent faces of COVID-19 have initiated several queries among huge populations, policy makers, general physicians, and scientific communities. The present review aims to provide some information regarding the molecular and cellular mechanisms underlying SARS-CoV-2 infection.

16.
Physiol Behav ; 272: 114357, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37741605

RESUMO

Glucocorticoids are one of steroid hormone and have a variety of functions including stress response, carbohydrate metabolism, and modulation of immune system in vertebrates. Corticosterone is the main glucocorticoid in birds, although the precise role of the glucocorticoid during immune challenge is not fully understood. Therefore, the purpose of the present study was to determine if a single subcutaneous injection of corticosterone could affect inflammation-related gene expressions in the spleen and liver of chicks (Gallus gallus). In addition, the effects of corticosterone injection on the food intake, cloacal temperature, formation of conditioned visual aversion, and plasma constituents were also measured. Corticosterone did not affect the food intake or cloacal temperature and did not cause conditioned visual aversion in chicks. The corticosterone injection was associated with a significant decrease in gene expression of several pro-inflammatory cytokines including inducible nitric oxide synthase and cyclooxygenase-2 in the spleen and liver at 1 and 3 h post-injection. Corticosterone increased the plasma glucose and uric acid concentrations and the antioxidant capacity. In summary, the present study suggests that corticosterone is likely not associated with food intake, cloacal temperature or the development of aversive sensation, but suppresses the synthesis of inflammation-associated bioactive molecules and increases the antioxidant capacity in chicks.


Assuntos
Corticosterona , Ingestão de Alimentos , Animais , Galinhas/fisiologia , Glucocorticoides , Antioxidantes , Imunidade , Inflamação/induzido quimicamente
17.
J Poult Sci ; 60: 2023031, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38145204

RESUMO

The pathogen-associated molecular patterns (PAMPs) lipopolysaccharide (LPS) and zymosan, derived from gram-negative bacteria and fungi, respectively, activate the innate immune system and cause injury to multiple organs, including the liver and intestine, in mammals. In rodents, PAMP-induced injury has been demonstrated to be potentiated by co-administration of D-galactosamine (D-GalN) in rodents. However, whether PAMPs and D-GalN collectively cause organ injury in birds remains unclear. The present study aimed to measure the effects of intraperitoneal injection of D-GalN with LPS or zymosan on parameters related to hepatic injury in chicks (Gallus gallus). Plasma aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) activities were not affected by intraperitoneal injection of D-GalN alone. Although these activities were not affected by LPS injection alone, they were increased by combining LPS with D-GalN. In contrast, plasma AST, ALT, and LDH activities were not affected by zymosan, both alone and with D-GalN. The expression of mRNAs for interleukin-6 (IL-6) and inducible nitric oxide synthase (iNOS) in the liver was significantly increased by the combination of LPS and D-GalN. In contrast, combining zymosan with D-GalN significantly increased iNOS mRNA expression, irrespective of hepatic injury. These results suggest that IL-6 may be the cause and/or result of hepatic injury in chicks. Additionally, chicks are tolerant to the hepatic effects of D-GalN, LPS, or zymosan alone.

18.
Front Med (Lausanne) ; 10: 1032531, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36844221

RESUMO

Introduction: There is a pressing need to develop novel drugs for treating patients with chronic hepatitis B (CHB), as commercially available antiviral drugs are endowed with safety and efficacy concerns. Methods: A phase III clinical trial was conducted with a therapeutic vaccine containing two antigens of the hepatitis B virus (HBV; named NASVAC) in 78 patients with CHB expressing both HBV DNA and elevated levels of alanine aminotransferase (ALT) in the blood. Five years after the end of treatment (EOT), 60 NASVAC-recipient patients were enrolled in this long-term follow-up study to evaluate the safety, antiviral potential, and liver-protective capacity of NASVAC. Results: NASVAC exhibited an excellent safety profile 5 years after EOT. The levels of HBV DNA in the sera were reduced in 55 of the 60 patients, and 45 of them were negative for HBV DNA in the sera. ALT levels were also normalized in 40 of the 60 patients 5 years after EOT. None of the patients receiving NASVAC developed liver cirrhosis or cancer. Discussion: The present study is the first to exhibit long-term follow-up data of a finite immune therapy for CHB that is safe and endowed with potent antiviral and liver-protecting capacities.

19.
Trop Med Health ; 51(1): 17, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36932428

RESUMO

BACKGROUND: The Philippines is ranked among the top countries with 200-300 annual deaths due to rabies. Most human rabies cases have been reported in remote areas, where dog surveillance is inadequate. Therefore, a strategy to effectively improve surveillance in remote areas will increase the number of detections. Detecting pathogens using portable real-time reverse transcription-polymerase chain reaction (RT-PCR) has the potential to be accepted in these areas. Thus, we aimed to develop an assay to detect the rabies virus (RABV) genome by combining the robust primer system LN34 with the PicoGene PCR1100 portable rapid instrument targeting RABV RNA (PCR1100 assay). METHODS: Procedures were optimised using an LN34 primer/probe set, KAPA3G Plant PCR Kit (KAPA Biosystems), FastGene Scriptase II (NIPPON Genetics), and an artificial positive control RNA. RESULTS: Positive control RNA showed an analytical limit of detection of 10 copies/µL without false positivity, generating results in approximately 32 min. Compared to dFAT or RT-qPCR using field samples, the sensitivity and specificity of the PCR1100 assay were 100%, and even lower copy numbers (approximately 10 copies/µL) were detected. CONCLUSIONS: This study demonstrated that the developed assay can detect rabies RNA in field samples. Because dog-mediated rabies is endemic in remote areas, the rapidity, mobility, and practicality of the PCR1100 assay as well as the high sensitivity of the LN34 system make it an ideal tool for the confirmation of rabies in these areas.

20.
J Histochem Cytochem ; 71(10): 537-554, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37728096

RESUMO

We tracked prosaposin (PSAP), a trophic factor, using an antibody specific to its proteolytic portion and an antibody to sortilin that traffics PSAP only to the lysosome. Immunostaining revealed that PSAP was distributed mainly on the basal side of seminiferous tubules, where many Sertoli cells and pachytene spermatocytes contained PSAP and its distribution differed depending on the stage of the spermatogenic cycle. The PSAP-sortilin complex was sorted to large lysosomes in the basal cytoplasm of Sertoli cells, where it may be processed into saposins. In contrast, in the thinner apical cytoplasm of Sertoli cells, PSAP in small lysosomes was transported to the apical side around sperm heads or into the lumen for secretion. The results of in situ hybridization analyses suggested that immature tubular cells in young animals produce PSAP to self-stimulate proliferation. However, in adults, not only Sertoli cells but also pachytene spermatocytes produce and secrete PSAP around germ cells or into the tubular lumen to stimulate cell proliferation or differentiation in a paracrine or autocrine manner. In summary, PSAP is not only a precursor of lysosomal enzymes but also a pivotal trophic factor in organogenesis in the immature testis and spermatogenesis in the mature testis.


Assuntos
Saposinas , Testículo , Ratos , Animais , Masculino , Sêmen , Células de Sertoli , Espermatogênese
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