Effect of platelet-activating factor on food intake, cloacal temperature, voluntary activity and crop emptying rate in chicks.

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.

Thyroid abscess associated with thyrotoxicosis caused by Yersinia enterocolitica subsp. palearctica in a patient with follicular adenoma of the thyroid gland.

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.

Possible role of neuropeptide Y on zymosan- and lipopolysaccharide-induced change in gastrointestinal feed passage via the medulla oblongata in chicks.

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.

Zymosan and lipopolysaccharide decrease gene expression of neuronal nitric oxide synthase in peripheral organs in chicks.

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.

Bangladesh records persistently increased number of dengue deaths in recent years: Dissecting the shortcomings and means to resolve.

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.

Rapid Detection of Severe Fever with Thrombocytopenia Syndrome Virus in the Acute Phase of Infection by Direct Real-Time Reverse Transcription without RNA Extraction.

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.

Comprehensive analysis of antigenic variations and genomic properties of hepatitis B virus in clinical samples in the mid-north east region of Bangladesh.

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.

D-Galactosamine Causes Liver Injury Synergistically with Lipopolysaccharide but not Zymosan in Chicks.

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.

Recent Dengue Infection in Bangladesh: A Seasonal Endemic Progressing to Year-long Serious Health Concern.

Dengue represents one of the most dangerous mosquito-borne viral diseases. Although the disease has been prevalent around the globe over the centuries, recent outbreaks of dengue have devasted the healthcare delivery system of many countries. Being a global infection, dengue virus (DENV) is endemically present mainly in Latin America and Caribbean countries as well as countries in South Asia. The recent outbreak of DENV infection has indicated an exceptional outbreak of DENV in some countries in South Asia. There has been a serious endemic of DENV during 2019. After a heterogeneous pause, another severe outbreak of DENV was reported in some Asian countries in 2023. Among the Asian countries, Bangladesh has reported an acute upsurge of DENV infection in 2023 with record numbers of fatalities. However, this pattern of DENV has not been detected in neighbors of Bangladesh, such as India or other countries in Southeast Asia. This provides an emergent task of dissecting the present DENV infection in Bangladesh from different angles to get insights for future containment of the DENV infection, not only in Bangladesh but also in other DENV endemic areas or DENV-native areas. How to cite this article: Akbar SMF, Khan S, Mahtab M, et al. Recent Dengue Infection in Bangladesh: A Seasonal Endemic Progressing to Year-long Serious Health Concern. Euroasian J Hepato-Gastroenterol 2023;13(2):145-151.