12 research outputs found
Layered Long Term Co-Culture of Hepatocytes and Endothelial Cells on a Transwell Membrane: Toward Engineering the Liver Sinusoid
This paper presents a novel liver model that mimics the liver sinusoid where most liver activities occur. A key aspect of our current liver model is a layered co-culture of primary rat hepatocytes (PRHs) and primary rat liver sinusoidal endothelial cells (LSECs) or bovine aortic endothelial cells (BAECs) on a transwell membrane. When a layered co-culture was attempted with a thin matrigel layer placed between hepatocytes and endothelial cells to mimic the Space of Disse, the cells did not form completely separated monolayers. However, when hepatocytes and endothelial cells were cultured on the opposite sides of a transwell membrane, PRHs co-cultured with LSECs or BAECs maintained their viability and normal morphology for 39 and 57 days, respectively. We assessed the presence of hepatocyte-specific differentiation markers to verify that PRHs remained differentiated in the long-term co-culture and analyzed hepatocyte function by monitoring urea synthesis. We also noted that the expression of cytochrome P-450 remained similar in the cocultured system from Day 13 to Day 48. Thus, our novel liver model system demonstrated that primary hepatocytes can be cultured for extended times and retain their hepatocyte-specific functions when layered with endothelial cells
Layered Hepatocytes and Endothelial Cells on a Transwell Membrane: Toward Engineering the Liver Sinusoid
This paper presents a novel liver model that mimics the liver sinusoid where most liver activities occur. A key aspect of our current liver model is a layered co-culture of primary rat hepatocytes (PRHs) and primary rat liver sinusoidal endothelial cells (LSECs) or bovine aortic endothelial cells (BAECs) on a transwell membrane. When a layered co-culture was attempted with a thin Matrigel layer placed between hepatocytes and endothelial cells to mimic the space of Disse, the cells did not form completely separated monolayers. However, when hepatocytes and endothelial cells were cultured on the opposite sides of a transwell membrane, PRHs co-cultured with LSECs or BAECs maintained their viability and normal morphology for 39 and 57 days, respectively. We assessed the presence of hepatocyte-speciο¬c differentiation markers to verify that PRHs remained differentiated in the long-term co-culture and analyzed hepatocyte function by monitoring urea synthesis. We also noted that the expression of cytochrome P-450 remained similar in the co-cultured system from day 1 to day 48. Thus, our novel liver model system demonstrated that primary hepatocytes can be cultured for extended times and retain their hepatocyte-speciο¬c functions when layered with endothelial cells
Clinical Features Present, Past & Future Prospective of Monkey Pox: A Orthopoxvirus
Some issues regarding the potential spread of monkeypox have arisen just as the international world is beginning to recover from the initial alarm that was caused by the probable spread of coronavirus disease 2019 (COVID-19). Despite the fact that parts of Africa have traditionally been more susceptible to monkeypox than other regions of the world, the majority of new cases that have been linked to the outbreak that began in 2022 have been reported in countries located in Europe and the western hemisphere. Despite the fact that a great number of organisations are working on contact-tracing activities at the moment, the origin of this outbreak is still unknown at this time. The monkeypox virus belongs to the family of viruses known as Poxviridae and the genus known as Orthopoxvirus. Following the eradication of smallpox across the globe in the 1970s, news of monkeypox caused widespread worry across the globe. Through vaccination with the smallpox virus, individuals were able to develop cross-immunity against monkeypox. After distribution of the smallpox vaccine was discontinued, the number of outbreaks of monkeypox rose. The monkeypox epidemic that occurred in the United States in 2003 was the first time that the disease gained extensive notice in the media. In spite of its name, the virus known as monkeypox is not transmitted by monkeys. Although a number of different kinds of rodents and other small mammals have been suggested as the primal hosts of the monkeypox virus, the virus\u27s true lineage is still a mystery. The virus that causes monkeypox was first identified in macaque monkeys, which is where the disease was first seen. When monkeypox does transfer from one person to another, it often does so through a person\u27s mucocutaneous lesions or through the respiratory droplets that they expel. However, this only happens very infrequently. However, supporting therapy can be given to reduce symptoms, and medications such tecovirimat may be administered in really severe cases. At this time, there is no specific treatment for patients who have infected the virus; however, supportive treatments can be given. It is debatable whether or not these treatments are successful in reducing symptoms because there are no concrete guidelines to follow in this regard
Modulation of Apoptotic Signaling by the Hepatitis B Virus X Protein
Worldwide, an estimated 350 million people are chronically infected with the Hepatitis B Virus (HBV); chronic infection with HBV is associated with the development of severe liver diseases including hepatitis and cirrhosis. Individuals who are chronically infected with HBV also have a significantly higher risk of developing hepatocellular carcinoma (HCC) than uninfected individuals. The HBV X protein (HBx) is a key regulatory HBV protein that is important for HBV replication, and likely plays a cofactor role in the development of HCC in chronically HBV-infected individuals. Although some of the functions of HBx that may contribute to the development of HCC have been characterized, many HBx activities, and their putative roles during the development of HBV-associated HCC, remain incompletely understood. HBx is a multifunctional protein that localizes to the cytoplasm, nucleus, and mitochondria of HBVβinfected hepatocytes. HBx regulates numerous cellular signal transduction pathways and transcription factors as well as cell cycle progression and apoptosis. In this review, we will summarize reports in which the impact of HBx expression on cellular apoptotic pathways has been analyzed. Although various effects of HBx on apoptotic pathways have been observed in different model systems, studies of HBx activities in biologically relevant hepatocyte systems have begun to clarify apoptotic effects of HBx and suggest mechanisms that could link HBx modulation of apoptotic pathways to the development of HBV-associated HCC
Human Liver Sinusoid on a Chip for Hepatitis B Virus Replication Study
We have developed a miniature human liver (liver-sinusoid-on-a-chip) model using a dual microchannel separated by a porous membrane. Primary human hepatocytes and immortalized bovine aortic endothelial cells were co-cultured on opposite sides of a microporous membrane in a dual microchannel with continuous perfusion. Primary human hepatocytes in this system retained their polygonal morphology for up to 26 days, while hepatocytes cultured in the absence of bovine aortic endothelial cells lost their morphology within a week. In order to demonstrate the utility of our human-liver-sinusoid-on-a-chip, human hepatocytes in this system were directly infected by Hepatitis B Virus (HBV). Expression of the HBV core antigen was detected in human hepatocytes in the microchannel system. HBV replication, measured by the presence of cell-secreted HBV DNA, was also detected. Importantly, HBV is hepatotropic, and expression of HBV RNA transcripts is dependent upon expression of hepatocyte-specific factors. Moreover, HBV infection requires expression of the human-hepatocyte-specific HBV cell surface receptor. Therefore, the ability to detect HBV replication and Hepatitis B core Antigen (HBcAg) expression in our microfluidic platform confirmed that hepatocyte differentiation and functions were retained throughout the time course of our studies. We believe that our human-liver-sinusoid-on-a-chip could have many applications in liver-related research and drug development
<span style="font-size:15.0pt;mso-bidi-font-size: 14.0pt;font-family:"Times New Roman","serif";mso-fareast-font-family:"Times New Roman"; mso-ansi-language:EN-US;mso-fareast-language:EN-US;mso-bidi-language:AR-SA" lang="EN-US">Comparative pharmacognostical studies of two medicinally important Indian <i style="mso-bidi-font-style:normal">Evolvulus</i> species</span>
564-570<span style="font-size:9.0pt;font-family:
" times="" new="" roman","serif";mso-fareast-font-family:"times="" roman";color:black;="" mso-ansi-language:en-us;mso-fareast-language:en-us;mso-bidi-language:ar-sa"="" lang="EN-US">The
genus Evolvulus consists of small herbs or under shrubs distributed in
the tropical and warm temperate regions of the world. Two species of this genus
have been reported from India, viz. E. alsinoides L. and E.
nummularius L. (Convolvulaceae).<span style="font-size:
9.0pt;font-family:" times="" new="" roman","serif";mso-fareast-font-family:"times="" roman";="" mso-ansi-language:en-us;mso-fareast-language:en-us;mso-bidi-language:ar-sa"="" lang="EN-US">
Both the species are traditionally being used as
nerve tonic and for the treatment of skin diseases. The current study was carried out to provide comparative
macro-microscopy, physicochemical parameters and TLC finger print profiles of
aforesaid Indian <span style="font-size:9.0pt;font-family:
" times="" new="" roman","serif";mso-fareast-font-family:"times="" roman";color:black;="" mso-ansi-language:en-us;mso-fareast-language:en-us;mso-bidi-language:ar-sa"="" lang="EN-US">Evolvulus
species.<span style="font-size:9.0pt;
font-family:" times="" new="" roman","serif";mso-fareast-font-family:"times="" roman";="" mso-ansi-language:en-us;mso-fareast-language:en-us;mso-bidi-language:ar-sa"="" lang="EN-US"> The microscopy showed anisocytic stomata in E. alsinoides while diacytic and
paracytic stomata in E. nummularius;
presence of stellate <span style="font-size:9.0pt;font-family:
" times="" new="" roman","serif";mso-fareast-font-family:"times="" roman";mso-ansi-language:="" en-us;mso-fareast-language:en-us;mso-bidi-language:ar-sa"="" lang="EN-US">trichomes, characteristic pith with spindle shaped deposition of calcium
oxalate crystals<span style="font-size:9.0pt;font-family:
" times="" new="" roman","serif";mso-fareast-font-family:timesnewroman;mso-ansi-language:="" en-us;mso-fareast-language:en-us;mso-bidi-language:ar-sa"="" lang="EN-US"> and starch grains only in E.
nummularius.<span style="font-size:9.0pt;font-family:
" times="" new="" roman","serif";mso-fareast-font-family:timesnewroman;mso-ansi-language:="" en-us;mso-fareast-language:en-us;mso-bidi-language:ar-sa"="" lang="EN-US"> Comparative TLC profile showed presence of some common as
well as differentiating bands in <span style="font-size:9.0pt;
font-family:" times="" new="" roman","serif";mso-fareast-font-family:timesnewroman;="" mso-ansi-language:en-us;mso-fareast-language:en-us;mso-bidi-language:ar-sa"="" lang="EN-US">methanolic
extract of Evolvulus sp. However, the chemical markers, viz. ferulic
acid, caffeic acid, Ξ² sitosterol and lupeol were present in <span style="font-size:9.0pt;
font-family:" times="" new="" roman","serif";mso-fareast-font-family:"times="" roman";="" mso-ansi-language:en-us;mso-fareast-language:en-us;mso-bidi-language:ar-sa"="" lang="EN-US">both the species. The macro-microscopy and TLC profiles may play an important role for identification and
quality evaluation <span style="font-size:9.0pt;font-family:
" times="" new="" roman","serif";mso-fareast-font-family:"times="" roman";mso-ansi-language:="" en-us;mso-fareast-language:en-us;mso-bidi-language:ar-sa"="" lang="EN-US">of two medicinally important <i style="mso-bidi-font-style:
normal">Evolvulus species.</span