Biomedical subjects

N Chen

Publications and source records attributed to N Chen.

At least 19 recordsLinked to original sources

PubMed2006

A genomic view of the sea urchin nervous system.

The sequencing of the Strongylocentrotus purpuratus genome provides a unique opportunity to investigate the function and evolution of neural genes. The neurobiology of sea urchins is of particular interest because they have a close phylogenetic relationship with chordates, yet a distinctive pentaradiate body plan and unusual neural organization. Orthologues of transcription factors that regulate neurogenesis in other animals have been identified and several are expressed in neurogenic domains before gastrulation indicating that they may operate near the top of a conserved neural gene regulatory network. A family of genes encoding voltage-gated ion channels is present but, surprisingly, genes encoding gap junction proteins (connexins and pannexins) appear to be absent. Genes required for synapse formation and function have been identified and genes for synthesis and transport of neurotransmitters are present. There is a large family of G-protein-coupled receptors, including 874 rhodopsin-type receptors, 28 metabotropic glutamate-like receptors and a remarkably expanded group of 161 secretin receptor-like proteins. Absence of cannabinoid, lysophospholipid and melanocortin receptors indicates that this group may be unique to chordates. There are at least 37 putative G-protein-coupled peptide receptors and precursors for several neuropeptides and peptide hormones have been identified, including SALMFamides, NGFFFamide, a vasotocin-like peptide, glycoprotein hormones and insulin/insulin-like growth factors. Identification of a neurotrophin-like gene and Trk receptor in sea urchin indicates that this neural signaling system is not unique to chordates. Several hundred chemoreceptor genes have been predicted using several approaches, a number similar to that for other animals. Intriguingly, genes encoding homologues of rhodopsin, Pax6 and several other key mammalian retinal transcription factors are expressed in tube feet, suggesting tube feet function as photosensory organs. Analysis of the sea urchin genome presents a unique perspective on the evolutionary history of deuterostome nervous systems and reveals new approaches to investigate the development and neurobiology of sea urchins.

Animals↗

PubMed2006

Tumor-suppression function of transcription factor USF2 in prostate carcinogenesis.

Although the transcription factor USF2 has been implicated in the regulation of cellular growth and proliferation, it is unknown whether alterations in USF2 contribute to tumorigenesis and tumor development. We examined the role of USF2 in prostate tumorigenesis. Western blot analysis revealed markedly decreased USF2 levels in three androgen-independent prostate cancer cell lines, PC-3, DU145, and M12, as compared to nontumorigenic prostate epithelial cells or the androgen-dependent cell line, LNCaP. Ectopic expression of USF2 in PC-3 cells did not affect the cell proliferation rate of PC-3 cells on plastic surfaces. However, it dramatically decreased anchorage-independent growth of PC-3 cells in soft agar (90-98% inhibition) and the invasion capability (80% inhibition) of PC-3 cells in matrix gel assay. Importantly, expression of USF2 in PC-3 cells inhibited the tumorigenicity of PC-3 cells in an in vivo nude mice xenograft model (80-90% inhibition). These results suggest that USF2 has tumor-suppression function. Consistent with its function in tumor suppression, we found that the USF2 protein is present in normal prostate epithelial cells but absent in 18 of 42 (43%) human prostate cancer tissues (P = 0.015). To further examine the functional role of USF2 in vivo, we generated mice with genetic deletion of USF2 gene. We found that USF2-null mice displayed marked prostate hyperplasia at a young age, suggesting that USF2 is involved in the normal growth and differentiation of prostate. Together, these studies demonstrate that USF2 has tumor-suppressor function and plays a role in prostate carcinogenesis.

Animals↗

PubMed2006

The importance of company: Na+ and Cl- influence substrate interaction with SLC6 transporters and other proteins.

SLC6 transporters, which include transporters for gamma-aminobutyric acid (GABA), norepinephrine, dopamine, serotonin, glycine, taurine, L-proline, creatine, betaine, and neutral cationic amino acids, require Na+ and Cl- for their function, and this review covers the interaction between transporters of this family with Na+ and Cl- from a structure-function standpoint. Because detailed structure-function information regarding ion interactions with SLC6 transporters is limited, we cover other proteins cotransporting Na+ or Cl- with substrate (SLClA2, PutP, SLC5A1, melB), or ion binding to proteins in general (rhodanese, ATPase, LacY, thermolysine, angiotensin-converting enzyme, halorhodopsin, CFTR). Residues can be involved in directly binding Na+ or Cl-, in coupling ion binding to conformational changes in transporter, in coupling Na+ or Cl- movement to transport, or in conferring ion selectivity. Coordination of ions can involve a number of residues, and portions of the substrate and coupling ion binding sites can be distal in space in the tertiary structure of the transporter, with other portions that are close in space thought to be crucial for the coupling process. The reactivity with methanethiosulfonate reagents of cysteines placed in strategic positions in the transporter provides a readout for conformational changes upon ion or substrate binding. More work is needed to establish the relationships between ion interactions and oligomerization of SLC6 transporters.

Animals↗

PubMed2006

Effects of immunisation against leptin on feed intake, weight gain, fat deposition and laying performance in chickens.

1. Three experiments were conducted to study the effects of leptin on weight gain and body composition in laying hens. 2. The effects of immunisation against chicken leptin on feed intake (FI), fat deposition and laying rate were observed in laying Guangdong yellow-feathered hens. Ten hens were inoculated with leptin immunogen on d 3, 31, 63 and 84, together with 10 control hens immunised with bovine serum albumin (BSA). In the 100-d experiment, immunisation against leptin increased blood anti-leptin antibody titres, slightly reduced plasma T3 concentrations, slightly decreased FI and increased live weight; however, laying rate was significantly depressed and abdominal fat mass was increased by the end of the 100-d experiment. 3. Passive immunisation of 50-d-old pullets with yolk extract containing anti-leptin antibody IgY significantly increased FI within 6 h of treatment compared with physiological saline treated controls. 4. In growing 70-d-old pullets, inoculation with 0.5 (group 1) or 1 (group 2) ml leptin immunogen on d 1 and 28 of the experiment slightly increased FI and significantly increased daily gain compared with BSA-immunised control pullets. Abdominal fat mass on d 49 increased from 48+/-4.5 g in controls to 66+/-3.5 and 80+/-3.1 g in groups 1 and 2, respectively. 5. It was suggested that immunisation against leptin mimicked loss of leptin bioactivity and might become a novel technique to stimulate fat growth in certain types of animal production.

Adipose Tissue↗

PubMed2006

Atomic force microscopy studies of conditioner thickness distribution and binding interactions on the hair surface.

The way in which common hair care products, such as conditioner, deposit onto and change hair properties is of interest in beauty care science, as these properties are closely tied to product performance. The binding interaction between conditioner and the hair surface is one of the important factors in determining the conditioner thickness distribution and consequently the proper functions of conditioner. In this study, atomic force microscopy was used to obtain the local conditioner thickness distribution, adhesive forces and effective Young's modulus mapping of various hair surfaces. The conditioner thickness was extracted by measuring the forces on the atomic force microscopy tip as it approached, contacted and pushed through the conditioner layer. The effective Young's moduli of various hair surfaces were calculated from the force distance curves using Hertz analysis. The intrinsic binding interactions between different silicones and the hair surface on the microscopic scale, as well as their effect on the effective Young's modulus of the hair, are also discussed. It was found that the effective Young's modulus of the hair is strongly affected by the binding of conditioner molecules on the hair surface.

Hair↗

PubMed2005

Complete coding sequences of the rabbitpox virus genome.

Rabbitpox virus (RPXV) is highly virulent for rabbits and it has long been suspected to be a close relative of vaccinia virus. To explore these questions, the complete coding region of the rabbitpox virus genome was sequenced to permit comparison with sequenced strains of vaccinia virus and other orthopoxviruses. The genome of RPXV strain Utrecht (RPXV-UTR) is 197 731 nucleotides long, excluding the terminal hairpin structures at each end of the genome. The RPXV-UTR genome has 66.5 % A + T content, 184 putative functional genes and 12 fragmented ORF regions that are intact in other orthopoxviruses. The sequence of the RPXV-UTR genome reveals that two RPXV-UTR genes have orthologues in variola virus (VARV; the causative agent of smallpox), but not in vaccinia virus (VACV) strains. These genes are a zinc RING finger protein gene (RPXV-UTR-008) and an ankyrin repeat family protein gene (RPXV-UTR-180). A third gene, encoding a chemokine-binding protein (RPXV-UTR-001/184), is complete in VARV but functional only in some VACV strains. Examination of the evolutionary relationship between RPXV and other orthopoxviruses was carried out using the central 143 kb DNA sequence conserved among all completely sequenced orthopoxviruses and also the protein sequences of 49 gene products present in all completely sequenced chordopoxviruses. The results of these analyses both confirm that RPXV-UTR is most closely related to VACV and suggest that RPXV has not evolved directly from any of the sequenced VACV strains, since RPXV contains a 719 bp region not previously identified in any VACV.

Base Sequence↗

PubMed2005

Morphological, nanomechanical and cellular structural characterization of human hair and conditioner distribution using torsional resonance mode with an atomic force microscope.

Characterization of the cellular structure and chemical and physical properties of hair are essential to develop better cosmetic products and advance the biological and cosmetic sciences. Although the morphology of the fine cellular structure of human hair has traditionally been investigated using scanning electron microscopy and transmission electron microscopy, atomic force microscopy can be used for characterization in ambient conditions without requiring specific sample preparations and surface treatment. In this study, the tapping and torsional resonance modes in an atomic force microscope are compared for measurements of stiffness and viscoelastic properties. The materials were mapped using amplitude and phase angle imaging. The torsional resonance mode showed advantages in resolving the in-plane (lateral) heterogeneity of materials. This mode was used for investigating and characterizing the fine cellular structure of human hair. Various cellular structures (such as the cortex and the cuticle) of human hair and fine sublamellar structures of the cuticle, such as the A-layer, the exocuticle, the endocuticle and the cell membrane complex were easily identified. The distribution and thickness of conditioner on the treated hair surface affects the tribological properties of hair. The thickness of the conditioner was estimated using force distance measurements with an atomic force microscope.

Hair↗

PubMed2005

Melanoma inhibitor of apoptosis protein is expressed differentially in melanoma and melanocytic naevus, but similarly in primary and metastatic melanomas.

BACKGROUND: Malignant melanoma is highly resistant to current treatments. The inhibitor of apoptosis protein (IAP) family member, melanoma IAP (ML-IAP), is overexpressed in some melanoma cell lines, rendering them resistant to apoptotic signals. Targeting ML-IAP is a promising approach to treating melanoma. However, the status of ML-IAP expression in human melanoma tissues and the difference in expression between melanoma and melanocytic naevus are not known. AIMS: To investigate these issues. METHODS: ML-IAP expression in 48 archived patient samples (34 melanomas and 14 dermal naevi) was assessed by immunohistochemistry and by in situ hybridisation and reverse transcription polymerase chain reaction (RT-PCR) assays developed for the study. RESULTS: Expression of ML-IAP was detected in 47.6-70.6% (10 of 21 to 24 of 34) of the melanomas, varying with detection methods. The expression rate in melanoma was much higher than that in melanocytic naevus (10.0-21.4%; one of 10 to three of 14). No significant difference was seen between primary and secondary melanomas. ML-IAP expression rates assessed by the three methods were in agreement. CONCLUSIONS: The ML-IAP expression rate in archived melanoma tissues is around 50-70%, with no difference between primary and secondary melanomas. A small number of dermal naevi ( approximately 20%) also expressed ML-IAP.

Adaptor Proteins, Signal Transducing↗

PubMed2004

Do hematopoietic cells exposed to a neurogenic environment mimic properties of endogenous neural precursors?

Hematopoietic progenitors are cells, which under challenging experimental conditions can develop unusual phenotypic properties, rather distant from their original mesodermal origin. As previously reported, cells derived from human umbilical cord blood (HUCB) or human bone marrow (BM) under certain in vivo or in vitro conditions can manifest neural features that resemble features of neural-derived cells, immunocytochemically and in some instances also morphologically. The present study explored how hematopoietic-derived cells would respond to neurogenic signals from the subventricular zone (SVZ) of adult and aged (6 and 16 months old) rats. The mononuclear fraction of HUCB cells was transplanted into the SVZ of immunosuppressed (single cyclosporin or three-drug treatment) animals. The triple-suppression paradigm allowed us to protect transplanted human cells within the brain and to explore further their phenotypic and migratory properties. One week after implantation, many surviving HUCB cells were located within the SVZ and the vertical limb of the rostral migratory stream (RMS). The migration of HUCB cells was restricted exclusively to the pathway leading to the olfactory bulb. In younger animals, grafted cells navigated almost halfway through the vertical limb, whereas, in the older animals, the migration was less pronounced. The overall cell survival was greater in younger animals than in older ones. Immunocytochemistry for surface CD antigen expression showed that many HUCB cells, either cultured or within the brain parenchyma, retained their hematopoietic identity. A few cells, identified by using human-specific antibodies (anti-human nuclei, or mitochondria) expressed nestin and doublecortin, markers of endogenous neural progenitors. Therefore, it is believed that the environment of the neurogenic SVZ, even in aged animals, was able to support survival, "neuralization," and migratory features of HUCB-derived cells.

Age Factors↗

PubMed2004

Green fluorescent protein bone marrow cells express hematopoietic and neural antigens in culture and migrate within the neonatal rat brain.

Finding a reliable source of alternative neural stem cells for treatment of various diseases and injuries affecting the central nervous system is a challenge. Numerous studies have shown that hematopoietic and nonhematopoietic progenitors derived from bone marrow (BM) under specific conditions are able to differentiate into cells of all three germ layers. Recently, it was reported that cultured, unfractionated (whole) adult BM cells form nestin-positive spheres that can later initiate neural differentiation (Kabos et al., 2002). The identity of the subpopulation of BM cells that contributes to neural differentiation remains unknown. We therefore analyzed the hematopoietic and neural features of cultured, unfractionated BM cells derived from a transgenic mouse that expresses green fluorescent protein (GFP) in all tissues. We also transplanted the BM cells into the subventricular zone (SVZ), a region known to support postnatal neurogenesis. After injection of BM cells into the neurogenic SVZ in neonatal rats, we found surviving GFP+ BM cells close to the injection site and in various brain regions, including corpus callosum and subcortical white matter. Many of the grafted cells were detected within the rostral migratory stream (RMS), moving toward the olfactory bulb (OB), and some cells reached the subependymal zone of the OB. Our in vitro experiments revealed that murine GFP+ BM cells retained their proliferation and differentiation potential and predominantly preserved their hematopoietic identity (CD45, CD90, CD133), although a few expressed neural antigens (nestin, glial fibrillary acdiic protein, TuJ1).

Animals↗

PubMed2004

Engineering RENTA, a DNA prime-MVA boost HIV vaccine tailored for Eastern and Central Africa.

For the development of human immunodeficiency virus type 1 (HIV-1) vaccines, traditional approaches inducing virus-neutralizing antibodies have so far failed. Thus the effort is now focused on elicitation of cellular immunity. We are currently testing in clinical trials in the United Kingdom and East Africa a T-cell vaccine consisting of HIV-1 clade A Gag-derived immunogen HIVA delivered in a prime-boost regimen by a DNA plasmid and modified vaccinia virus Ankara (MVA). Here, we describe engineering and preclinical development of a second immunogen RENTA, which will be used in combination with the present vaccine in a four-component DNA/HIVA-RENTA prime-MVA/HIVA-RENTA boost formulation. RENTA is a fusion protein derived from consensus HIV clade A sequences of Tat, reverse transcriptase, Nef and gp41. We inactivated the natural biological activities of the HIV components and confirmed immunogenicities of the pTHr.RENTA and MVA.RENTA vaccines in mice. Furthermore, we demonstrated in mice and rhesus monkeys broadening of HIVA-elicited T-cell responses by a parallel induction of HIVA- and RENTA-specific responses recognizing multiple HIV epitopes.

AIDS Vaccines↗

PubMed2004

Occurrence of Ross River virus and Barmah Forest virus in mosquitoes at Shoalwater Bay military training area, Queensland, Australia.

Shoalwater Bay military training area (SWBTA), 2,713 km2 of land located 50-80 km north of Rockhampton, Queensland, Australia, is used by Australian and allied forces for training purposes. Between March 1998 and February 2000, monthly collections of mosquitoes at 15 sites were conducted using carbon dioxide-baited traps to study the seasonal occurrence of mosquitoes and Ross River virus (RRV) and Barmah Forest virus (BFV) in mosquitoes. A total of 72,616 mosquitoes, comprising 3,897 pools were collected, and 2,428 pools were tested using a reverse transcriptase-polymerase chain reaction. A total of 15 pools of mosquitoes were positive for virus, 10 RRV and five BFV. Blood meals from an additional 763 mosquitoes were tested by a gel diffusion assay, and the majority (96%) of those identified were from kangaroo, which was the most common mammal in the study area. The results indicate that Culex annulirostris Skuse and Ochlerotatus vigilax (Skuse) are the main vectors of RRV at SWBTA.

Alphavirus↗

PubMed2003

Extracellular carbohydrate-signal triggering cAMP-dependent protein kinase-dependent neuronal actin-reorganization.

Cell surface glycoconjugates are thought to mediate cell-cell recognition and to play roles in neuronal development and functions. We demonstrated here that exposure of neuronal cells to nanomolar levels of glyco-chains with an N-acetylgalactosamine (GalNAc) residue at the non-reducing termini (GalNAc-S) such as GalNAcbeta4(Neu5Acalpha3)Galbeta4GlcCer (GM2) ganglioside, its oligosaccharide portion, GalNAcbeta4Galbeta4GlcCer (Gg(3)) Cer, GalNAcalpha3GalNAcbeta3Galalpha4Galbeta4GlcCer (Gb(5)) Cer (Forssman hapten) and alpha1-4 linked oligomers of GalNAc, induced a rapid and transient activation of cAMP-dependent protein kinase (PKA) in subplasmalemma. The treatment was accompanied by peripheral actin polymerization and filopodia formation in NG108-15 cells and primary cultured hippocampal neurons, but not in glial cells. A cAMP-dependent protein kinase (PKA) selective inhibitor and an adenylate cyclase inhibitor blocked both PKA activation and the subsequent filopodia formation. A small GTPase cdc42 was a potential downstream target of GalNAc-S-activated PKA. These results suggest that extracellular GalNAc-S serve as potential regulators of the filopodia formation in neuronal cells by triggering the activation of PKA followed by cdc42 up-regulation via a cell surface receptor-like component. Filopodia formation induced by GalNAc-S may have a physiological relevance because long-term exposure to GalNAc-S enhanced F-actin-rich dendrite generation of primary cultured hippocampal neurons, and PKA-dependent dendritic outgrowth and branch formation of primary cultured cerebellar Purkinje neurons, in which actin isoforms were localized to motile structures in dendrites. These findings provide evidence for a novel GalNAc/PKA-signaling cascade in regulating some neuronal maturation.

Acetylgalactosamine↗

PubMed2003

Use of green fluorescent protein to quantify the growth of Colletotrichum during infection of tobacco.

To develop a quantitative assay of fungal growth inside plant tissues, strains of Colletotrichum destructivum and Colletotrichum orbiculare were transformed with a modified green fluorescent protein (GFP) gene fused with a glyceraldehyde-3-phosphate dehydrogenase promoter from Aspergillus nidulans. Transformants expressed GFP in culture and had the same growth rate and general appearance as the wild type. GFP was observed in all fungal structures during infection of leaves of Nicotiana benthamiana, except for the melanized appressoria and setae. The timing and appearance of the fungal structures in the host appeared to be identical to that of the wild type. GFP accumulation in inoculated leaves of N. benthamiana was quantified in leaf extracts using a fluorescence microplate reader, and the quantity of fluorescence was strongly correlated with the growth of the fungus as measured by the amount of fungal actin gene expression using Northern blot hybridizations. These results demonstrated that assaying green fluorescence levels from a GFP-transformed fungus is an accurate, fast and easy means of quantifying fungal growth inside host plant cells.

Actin Cytoskeleton↗

PubMed2003

Ganglioside/calmodulin kinase II signal inducing cdc42-mediated neuronal actin reorganization.

Cell surface glycoconjugates are thought to mediate cell-cell recognition and play roles in neuronal development and functions. We demonstrated here that exposure of neuronal cells to nanomolar levels of gangliosides Neu5Acalpha 8Neu5Acalpha 3Galbeta 4GlcCer, Galbeta 3GalNAcbeta 4(Neu5Acalpha 8Neu5Acalpha 3)Galbeta 4GlcCer (GD1b), Neu5Acalpha 3Galbeta 3GalNAcbeta 4(Neu5Acalpha 8Neu5Acalpha 3)Galbeta 4GlcCer (GT1b) or its oligosaccharide portion induced a rapid and transient activation of Ca2+/calmodulin-dependent protein kinase II (CaM-KII) in the subplasmalemma. Galbeta 3GalNAcbeta 4(Neu5Acalpha 3)Galbeta 4GlcCer (GM1), GalNAcbeta 4(Neu5Acalpha 3)Galbeta 4GlcCer, Neu5Acalpha 3Galbeta 4GlcCer, Neu5Acalpha 3Galbeta 3GalNAcbeta 4(Neu5Acalpha 3)Galbeta 4GlcCer (GD1a), and Neu5Acalpha 8Neu5Acalpha 3Galbeta 3GalNAcbeta 4(Neu5Acalpha 8Neu5Acalpha 3)-Galbeta 4GlcCer were ineffective. GT1b and GD1b stimulated transient elevation of bulk cytosolic Ca2+ levels while GM1 slightly elevated the levels and GD1a did not. Thus, the cytosolic Ca2+ elevation by the gangliosides may trigger the CaM-KII activation. The treatment was accompanied by peripheral actin polymerization and filopodia formation in NG108-15 cells and primary hippocampal neurons, but not in glial cells. CaM-KII inhibitors blocked both CaM-KII activation and the subsequent filopodia formation. A small G-protein cdc42 was a potential downstream target of CaM-KII activated by the gangliosides. These results suggest that oligosaccharides of the gangliosides serve as potential regulators of the filopodia formation in neuronal cells by triggering the activation of CaM-KII followed by cdc42 up-regulation via a cell surface receptor-like component. The filopodia formation induced by the gangliosides may have a physiological relevance because long-term exposure of hippocampal neurons to GT1b oligosaccharide induced advanced dendritogenesis. Furthermore, exposure of cerebellar neurons to GT1b oligosaccharide facilitated CaM-KII-dependent dendritic outgrowth and branch formation of cerebellar Purkinje neurons, in which actin isoforms were localized to motile structures in dendrites. Thus, the ganglioside/CaM-KII signal plays a role in modulating dendritic morphogenesis by inducing cdc42-mediated actin reorganization.

Actins↗

PubMed2003

The role of ethylene during the infection of Nicotiana tabacum by Colletotrichum destructivum.

Two periods of increased ethylene production were observed after inoculation of Nicotiana tabacum by Colletotrichum destructivum. This pathogen exhibits an intracellular hemibiotrophic infection process, with a biotrophic phase followed by a necrotrophic phase. Ethylene production first increased during the biotrophic phase with a peak at 24 h before the necrotrophic phase. A second increase in ethylene occurred late in the necrotrophic phase when the lesions were expanding. Two different 1-aminocyclopropane-1-carboxylic acid synthase genes showed increased expression after the first ethylene peak with a maximum at 24 h before the second ethylene increase. Expression of an 1-aminocyclopropane-1-carboxylic acid oxidase (ACO) gene increased during the first ethylene peak and then declined at the beginning of the second ethylene increase. A second ACO gene showed relatively little change in expression during infection with slightly higher expression at 24 h before the second ethylene increase, and a third ACO gene showed a progressive decline in expression with a major decrease occurring before the second ethylene increase. Inoculation of ethylene-insensitive tobacco with C. destructivum revealed that it was more susceptible than the wild type. The changes in ethylene production and associated gene expression as well as the increased disease susceptibility of ethylene-insensitive tobacco indicate that ethylene plays a role in this interaction, perhaps as a signalling molecule to trigger defense mechanisms.

Base Sequence↗

PubMed2003

Therapeutic and reproductive cloning--implications and recommendations.

The announcement of Dolly's birth took the world by storm, mainly because what was thought impossible has become possible. Optimism that new approaches in agriculture and medicine abound, as much as fear and imagination leading to Frankenstein-like scenarios. Scientifically, cloning refers to replicating an animal with the same nuclear genetic material; whilst it may refer to embryos as the source material, the current storm refers to differentiated ("somatic") cells. Cloning technology is useful in the following areas: agriculture, to produce animals of superior or specific qualities; endangered animals, to increase genetic diversity through widening the gene pool; understanding fundamental questions in developmental embryology, through the use of laboratory animals; and in human therapy, to produce cells and possibly tissues for repair and regeneration. In the first 2 instances, it is reproductive cloning. In the last instance, it is therapeutic cloning, as no individuals are "produced". Human reproductive cloning is not allowed by all governments that have deliberated on it, and therapeutic cloning is allowed by some under certain circumstances. As therapeutic cloning has great potential in cures of many diseases, it should be allowed but with safeguards to prevent abuse and reproductive cloning in the human.

Animals↗

PubMed2002

Innate immune responses in viral encephalitis.

The innate immune system is multifaceted, comprised of preformed factors, cells, and many proteins and lipid mediators produced by those cells. In the CNS these are critical in initiation and amplification of the inflammatory response and in the subsequent elicitation of the specific T cell response to viral encephalitis. Cells that are resident in brain parenchyma and peripheral cells that are recruited both play key roles in the hosts's responses. Unlike the peripheral compartments, in the CNS, non-cytolytic means of eliminating viral infections have been critical, since, in contrast to columnar epithelial cells, neurons are non-renewing. When the innate immune responses are inefficient or absent in viral encephalitis, pathology is more likely. Much more work remains to elucidate all of the critical cells and their mediators, as well as to develop new therapies for infections of the CNS.

Acute Disease↗