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Background Calcium signaling are conserved from invertebrates to vertebrates and plays critical roles in many molecular mechanisms of embryogenesis and postnatal development. As a critical component of the signaling pathway, the RyR medicated calcium-induced calcium release signaling system, has been well studied along with their regulator FK506-binding protein 12 (FKBP12/Calstabin). Lack of FKBP12 is known to result in lethal cardiac dysfunction in mouse. However, precisely how FKBP12 is regulated and effects calcium signaling in Drosophila melanogaster remains largely unknown. Results In this study, we identified both temporal and localization changes in expression of DmFKBP12, a translational and transcriptional regulator of Drosophila RyR (DmRyR) and FKBP12, through embryonic development. DmFKBP12 is first expressed at the syncytial blastoderm stage and undergoes increased expression during the cellular blastoderm and early gastrulation stages. At late gastrulation, DmFKBP12 expression begins to decline until it reaches homeostasis, which it then maintains throughout the rest of development. Throughout these described changes in expression, DmFKBP12 mRNA remain stable, which indicates that protein dynamics are attributed to regulation at the mRNA to protein translation level. In addition to temporal changes in expression, dynamic expression profiles during Drosophila development also revealed DmFKBP12 localization. Although DmFKBP12 is distributed evenly between the anterior to posterior poles of the blastoderm egg, the protein is expressed more strongly in the cortex of the early Drosophila gastrula with the highest concentration found in the basement membrane of the cellular blastoderm. Fertilized egg, through the profile as under-membrane cortex distribution concentering onto basement at cellular blastoderm, to the profile as three-gem layer localization in primitive neuronal and digestion architecture of early Drosophila gastrula. By late gastrulation, DmFKBP12 is no longer identified in the yolk or lumen of duct structures and has relocated to the future brain (suboesophageal and supraesophageal ganglions), ventral nervous system, and muscular system. Throughout these changes in distribution, in situ DmFKBP12 mRNA monitoring detected equal distribution of DmFKBP12 mRNA, once again indicating that regulation of DmFKBP12 occurs at the translational level in Drosophila development. Conclusion As a critical regulator of the DmRyR-FKBP complex, DmFKBP12 expression in Drosophila fluctuates temporally and geographically with the formation of organ systems. These finding indicate that DmFKBP12 and RyR associated calcium signaling plays an essential role in the successful development of Drosophila melanogaster. Further study on the differences between mammalian RyR-FKBP12 and Drosophila DmRyR-FKBP12 can be exploited to develop safe pesticides. Electronic supplementary material The online version of this article (10.1186/s13578-019-0270-6) contains supplementary material, which is available to authorized users.

Background In the past 30 years, incidences of non-alcoholic fatty liver disease (NAFLD) has risen by 30%. However, there is still no clear mechanism or accurate method of anticipating liver failure. Here we reveal the phase transitions of liquid crystalline qualities in hepatic lipid droplets (HLDs) as a novel method of anticipating prognosis. Methods NAFLD was induced by feeding C57BL/6J mice on a high-fat (HiF) diet. These NAFLD livers were then evaluated under polarized microscopy, X-ray diffraction and small-angle scattering, lipid component chromatography analysis and protein expression analysis. Optically active HLDs from mouse model and patient samples were both then confirmed to have liquid crystal characteristics. Liver MAP1LC3A expression was then evaluated to determine the role of autophagy in liquid crystal HLD (LC-HLD) formation. Results Unlike the normal diet cohort, HiF diet mice developed NAFLD livers containing HLDs exhibiting Maltese cross birefringence, phase transition, and fluidity signature to liquid crystals. These LC-HLDs transitioned to anisotropic crystal at 0 °C and remain crystalline. Temperature increase to 42 °C causes both liquid crystal and crystal HLDs to convert to isotropic droplet form. These isotropic HLDs successfully transition to anisotropic LC with fast temperature decrease and anisotropic crystal with slow temperature decrease. These findings were duplicated in patient liver. Patient LC-HLDs with no inner optical activity were discovered, hinting at lipid saturation as the mechanism through which HLD acquire LC characteristics. Downregulation of MAP1LC3A in conjunction with increased LC-HLD also implicated autophagy in NAFLD LC-HLD formation. Conclusions Increasing concentrations of amphiphilic lipids in HLDs favors organization into alternating hydrophilic and hydrophobic layers, which present as LC-HLDs. Thus, evaluating the extent of liquid crystallization with phase transition in HLDs of NAFLD patients may reveal disease severity and predict impending liver damage.

During chick embryo development, the liquid crystals appear in more than 20 organs at certain developmental stages, and vanish in early post-natal stage. In this study, we found a complex i...

Whether neurogenesis occurs in the adult human brain has been a long-debated topic fueled by conflicting data both for and against neurogenesis in the mature brain. Recent reports from two independent teams may have indubitably proven that adult, hippocampal neurogenesis persists throughout the human lifespan. Llorens-Martín et al. found that thousands of immature, neurogenesis related, doublecortin-positive (DCX+) labelled neurons can be detected in the human dentate gyrus (DG) up to the eighth decade of life. While the presence of these DCX+ neurons decrease with age, they are significantly decrease in patient with Alzheimer’s disease. Another group have also found mammalian embryonic Hopx+ precursors to persist beyond the early development stage as quiescent Hopx+ radial glial-like neural progenitors during early postnatal period, then as Hopx+ adult dentate neural progenitors. Together, the findings from these two groups suggest that unlike the previously thought, neurogenesis and neuroplasticity can occur well into adulthood in some capacity, at least in the hippocampus. These recent findings that neurogenesis can occur beyond development have brought into questions whether physical exercise can be shown to promote neurogenesis and brain health, as it has been shown to promote the function of other organ systems. Some data has already shown physical exercise to induce adult hippocampal neurogenesis (AHN) as demonstrated by restoration of cognitive functions, improvement of synaptic plasticity, and enhancement of angiogenesis. A large-scale meta-analysis has also demonstrated that 45–60 min of moderate-intensity physical exercise to dramatically improve cognitive functions in human subjects over the age of 50. Given these convergent developments in our understanding of neurogenesis and exercise induced improvement in cognitive function, we speculate that hippocampal neurogenesis can be promoted by physical exercise and discuss the current molecular evidence supporting the likely molecular pathways involved.

Apicomplexan parasites have challenged researchers for nearly a century. A major challenge to developing efficient treatments and vaccines is the parasite’s ability to change its cellular and molecular makeup to develop intracellular and extracellular niches in its hosts. Ca2+ signaling is an important messenger for the egress of the malaria parasite from the infected erythrocyte, gametogenesis, ookinete motility in the mosquito, and sporozoite invasion of mammalian hepatocytes. Calcium-dependent protein kinases (CDPKs) have crucial functions in calcium signaling at various stages of the parasite’s life cycle; this therefore makes them attractive drug targets against malaria. Here, we summarize the functions of the various CDPK isoforms in relation to the malaria life cycle by emphasizing the molecular mechanism of developmental progression within host tissues. We also discuss the current development of anti-malarial drugs, such as how specific bumped kinase inhibitors (BKIs) for parasite CDPKs have been shown to reduce infection in Toxoplasma gondii, Cryptosporidium parvum, and Plasmodium falciparum. Our suggested combinations of BKIs, artemisinin derivatives with peroxide bridge, and inhibitors on the Ca(2+)-ATPase PfATP6 as a potential target should be inspected further as a treatment against malaria.

Macrophages are traditionally viewed as a key component of the immunity defense system. Recent studies have identified resident macrophages in multiple organs including the heart, in which the cells perform their crucial role on tissue repair after myocardial infarction (MI). The cardiac-specific macrophages interdigitate with cardiomyocytes particularly at the atrioventricular node region. The integrative communication between macrophage and cardiomyocytes can modulate the contractile function of the heart. Coordinated control of intracellular calcium signaling and intercellular electrical conduction via the syncytium network underlie the synchronized beating of the heart. In this review article, we introduce the concept the syncytium calcium signaling in the cardiomyocytes can modulate gene expression in the resident macrophages and their integration with the cardiomyocytes. The cardiac macrophages originate from bone marrow stem cells, migrate to local via vessel, and settle down as a naturalization process in heart. As the macrophages perform on regulating electrical conduction, and accomplish post MI non-scared completed regeneration or partial regeneration with fibrotic scar at different stage of postnatal development, we understand that multiple functions of cardiac macrophage should carry on with diverse linages. The naturalization process in heart of macrophages to the cardiomyocytes serves important roles to control of electrical signaling and calcium-dependent contractile function of the heart.

Background FK506-binding proteins (FKBPs) have become the subject of considerable interest in several fields, leading to the identification of several cellular and molecular pathways in which FKBPs impact prenatal development and pathogenesis of many human diseases. Main body This analysis revealed differences between how mammalian and Drosophila FKBPs mechanisms function in relation to the immunosuppressant drugs, FK506 and rapamycin. Differences that could be used to design insect-specific pesticides. (1) Molecular phylogenetic analysis of FKBP family proteins revealed that the eight known Drosophila FKBPs share homology with the human FKBP12. This indicates a close evolutionary relationship, and possible origination from a common ancestor. (2) The known FKBPs contain FK domains, that is, a prolyl cis/trans isomerase (PPIase) domain that mediates immune suppression through inhibition of calcineurin. The dFKBP59, CG4735/Shutdown, CG1847, and CG5482 have a Tetratricopeptide receptor domain at the C-terminus, which regulates transcription and protein transportation. (3) FKBP51 and FKBP52 (dFKBP59), along with Cyclophilin 40 and protein phosphatase 5, function as Hsp90 immunophilin co-chaperones within steroid receptor-Hsp90 heterocomplexes. These immunophilins are potential drug targets in pathways associated with normal physiology and may be used to treat a variety of steroid-based diseases by targeting exocytic/endocytic cycling and vesicular trafficking. (4) By associating with presinilin, a critical component of the Notch signaling pathway, FKBP14 is a downstream effector of Notch activation at the membrane. Meanwhile, Shutdown associates with transposons in the PIWI-interacting RNA pathway, playing a crucial role in both germ cells and ovarian somas. Mutations in or silencing of dFKBPs lead to early embryonic lethality in Drosophila. Therefore, further understanding the mechanisms of FK506 and rapamycin binding to immunophilin FKBPs in endocrine, cardiovascular, and neurological function in both mammals and Drosophila would provide prospects in generating unique, insect specific therapeutics targeting the above cellular signaling pathways. Conclusion This review will evaluate the functional roles of FKBP family proteins, and systematically summarize the similarities and differences between FKBP proteins in Drosophila and Mammals. Specific therapeutics targeting cellular signaling pathways will also be discussed.

Background Massive liquid crystal droplets have been found during embryonic development in more than twenty different tissues and organs, including the liver, brain and kidney. Liquid crystal deposits have also been identified in multiple human pathologies, including vascular disease, liver dysfunction, age-related macular degeneration, and other chronic illnesses. Despite the involvement of liquid crystals in such a large number of human processes, this phenomenon is poorly understood and there are no in vitro systems to further examine the function of liquid crystals in biology. Results We report the presence of tubular birefringent structures in embryoid bodies (EBs) differentiated in culture. These birefringent tubular structures initiate at the EB surface and penetrated the cortex at a variety of depths. Under crossed polarized light, these tubules are seen as a collection of birefringent Maltese crosses and tubules with birefringent walls and a non-birefringent lumen. The fluidity of these birefringent structures under pressure application led to elongation and widening, which was partially recoverable with pressure release. These birefringent structures also displayed heat triggered phase transition from liquid crystal to isotropic status that is partially recoverable with return to ambient temperature. These pressure and temperature triggered changes confirm the birefringent structures as liquid crystals. The first report of liquid crystal so early in development. Conclusion The structure of the liquid crystal tubule network we observed distributed throughout the differentiated embryoid bodies may function as a transportation network for nutrients and metabolic waste during EB growth, and act as a precursor to the vascular system. This observation not only reveals the involvement of liquid crystals earlier than previously known, but also provides a method for studying liquid crystals in vitro. Electronic supplementary material The online version of this article (doi:10.1186/s13578-016-0130-6) contains supplementary material, which is available to authorized users.

Calcium carbonate is often used as an efficient antacid that absorbs and neutralizes stomach acid while providing calcium for healthy bones. Taking advantage of the lack of adverse side effects of calcium, new drug delivery systems consisting of drug-supported spherical microparticles are being developed. We have reported in our previous studies that a natural process producing calcium carbonate microparticles can be found during avian development. These natural systems provide inspiration for designing more efficient microparticle facilitated drug-delivery systems. In this study, the formation and re-absorption of calcium carbonate crystals were tracked during Gallina N. meleagris embryogenesis and early postnatal development. The study demonstrated that the formation of calcium carbonate microparticles, as calcium is transferred from the eggshell into the egg sac, is a process of calcium preservation. X-ray diffraction showed that calcium carbonate crystal is mainly preserved in the vaterite isoform. Calcium incorporated into the yolk sac during this process can be easily assimilated as necessary during postnatal development. Eons of evolution have yielded a calcium preservation process that produces an iso-form of crystalline calcium most readily absorbed by the organism. Our previous results indicate that this biological system is likely a lyotropic process, the method that is currently being used for the production of microparticle drug delivery systems. In this work, our data suggests that calcium carbonate crystal can also initiate its crystallization from the center of liquid crystal, recognizable by a chimeric thermal phase transition. Our work provides valuable information for designing more efficient microparticle for drug-delivery.

The human immunodeficiency virus type 1 (HIV-1) transgenic (Tg) rat model incorporates a noninfectious viral genome that is under similar regulatory control mechanisms in vivo as those that exist with natural infection in humans. Vitamin A (VA) deficiency in humans has been associated with progressive systemic HIV disease and with impaired cognition in rodent models. The effects on of VA deficiency on the development of behavioral abnormalities with HIV infection have not been previously described. In these studies, wild-type (Wt) and Tg rats maintained on either a normal (VA+) or a VA-deficient (VA-) diet were examined for activity in an open field (horizontal activity, total distance, vertical activity, and rearing) and on rotarod testing. On both open field and rotarod testing, the Tg rats performed worse than the Wt rats, with the most severe deficits noted in the TgVA- animals. Analysis of the specific effects of the presence of the HIV transgene and the diet on the performance on the open field tests showed a dominant effect from the transgene on all of the tests, with an effect from the diet on only the number of rearings. On rotarod testing, effects form both the diet and the transgene were observed at lower speeds, at the highest speeds, and on the accelerating rotarod. These studies therefore demonstrate that behavioral and motor abnormalities can be detected in this model and are likely due to similar mechanisms by which humans infected with HIV might develop cognitive-motor impairment in association with VA deficiency.

Accelerated bone loss leading to osteopenia, osteoporosis, and bone fracture is a major health problem that is increasingly common in human immunodeficiency virus (HIV) infected patients. The underlying pathogenesis is unclear but occurs in both treatment naïve and individuals receiving antiretroviral therapies. We developed an HIV-1 transgenic rat that exhibits many key features of HIV disease including HIV-1 induced changes in bone mineral density (BMD). A key determinant in the rate of bone loss is the differentiation of osteoclasts, the cells responsible for bone resorption. We found HIV-1 transgenic osteoclast precursors (OCP) express higher levels of suppressor of cytokine signaling-1 (SOCS-1) and TNF receptor associated factor 6 (TRAF6) and are resistant to interferon-gamma (IFN-γ) mediated suppression of osteoclast differentiation. Our data suggest that dysregulated SOCS-1 expression by HIV-1 transgenic OCP promotes osteoclastogenesis leading to the accelerated bone loss observed in this animal model. We propose that elevated SOCS-1 expression in OCP antagonizes the inhibitory effects of IFN-γ and enhances receptor activator of NF-kB ligand (RANKL) signaling which drives osteoclast differentiation and activation. Understanding the molecular mechanisms of HIV-associated BMD changes has the potential to detect and treat bone metabolism disturbances early and improve the quality of life in patients.

The HIV-1 transgenic (TG) rat has been shown to be a useful model of nervous system disease that occurs in human HIV-1 infection. Studies were, therefore, performed to examine characteristics of the immune response in the periphery and brain of the animals and expression of factors in the nervous system that might be associated with neurotoxicity. Activated splenocytes from wild-type (WT) and TG rats were stimulated with either CD3/CD28 or with lipopolysaccharide (LPS) and examined for proliferative responses and for proinflammatory cytokine (IFN-γ, TNF-α and IL-1β) secretion. Brain tissue lysates from the rats were also examined for proinflammatory cytokine levels and tissue sections were stained by immunofluorescence for class II MHC+, ED1+ or Iba1+ (for macrophages and microglial cells), and for GFAP+ (for astrocytes) cells and for co-labeling of these cells for TNF-α. Co-labeling was also performed to identify cells expressing HIV-1 gp160, tat, nef and vif. Finally, on Western blots brain tissue lysates were examined for phosphorylation of Erk1/2, p38, JNK-SAPK and Erk5. TG rat splenocyte proliferative responses were higher than for WT with CD3/CD28-stimulation but lower than WT with LPS stimulation. CD3/CD28-stimulated TG rat splenocytes also secreted higher levels of IFN-γ, TNF-α and IL-1β whereas LPS-stimulated TG rat splenocytes secreted higher levels of only TNF-α than cultures from WT rats. Levels of all three cytokines were higher in brain lysates from TG rats than for WT rats. On immunofluorescence staining of corresponding sections of brain, TG rats contained increased numbers of class II MHC+ and ED1+ cells, and there was also increased co-labeling or these cells as well as astrocytes for TNF-α. Iba1+ cells showed positive staining for all of the HIV proteins whereas astrocytes showed significant positive staining for only nef and vif. Phosphorylation of Erk1/2, p38 and JNK/SAPK was detected for both TG and WT rat tissues with higher levels of phosphorylation forms of these proteins detected in the TG rat brain. Phosphorylation of Erk5, a marker that is associated with specifically neuronal repair, was detected only in TG rat brain. These studies suggest that activated nervous system mononuclear phagocytes and astrocytes expressing HIV-1 gene products in specific patterns are associated with neurodegeneration in the HIV-1 TG rat.

Opioid use in HIV infection has been associated with an increased frequency of neurological disease and cognitive impairment and vitamin A deficiency has been linked to progressive HIV disease in drug users. In this report the potential effects of these factors, alone and in combination, on gamma amino butyric acid (GABA)-expression interneurons in hippocampus in the HIV-1 transgenic rat (TG) model were studied. TG and wild-type (WT) F344 Fisher rats that were vitamin A deficient from birth were implanted either with a 37.5 mg morphine tablet or with a matching placebo and total numbers of neurons and of parvalbumin+ neurons were quantitated and parvalbumin expression was quantitated in the CA1 hippocampal region of the rats. These studies showed that total neuronal numbers were decreased in the TG versus WT Fisher rats and that this decrease was enhanced by the vitamin A deficient diet and by treatment with morphine. In contrast, there was no significant change noted in numbers of parvalbumin+ neurons. However, levels of parvalbumin expression were decreased for vitamin A deficient and morphine-treated WT rats as compared to WT rats on the normal diet and placebo-treated WT rats. For TG rats, parvalbumin expression was higher for vitamin A deficient TG rats treated with either placebo or morphine than for WT vitamin A deficient rats treated with placebo, and placebo treated vitamin A deficient TG rats showed higher expression than morphine treated vitamin A deficient rats. Expression was also higher for vitamin A deficient morphine-treated rats than for the corresponding WT rat groups and for vitamin A deficient TG rats treated with placebo. For the remaining groups, parvalbumin was similar for the TG and WT rats. These findings suggest that in hippocampus vitamin A deficiency and morphine can increase parvalbumin expression, perhaps as a manifestation of a stress response. Parvalbumin-expressing GABA-ergic interneurons regulate the primary neuronal output from hippocampus that is important for memory and behavior. Therefore, these studies suggest that vitamin A deficiency and morphine might have effects that may impact such outputs and thereby have lasting effects on cognitive status.

Vitamin A (VA) deficiency in HIV infection has been associated with more progressive HIV disease which may be enhanced by opioid use. In these studies were examined the effects of VA deficiency and morphine on frontal cortex neuronal numbers in the HIV-1 transgenic (Tg) rat. These studies showed that totals numbers of neurons were similar for rats on the VA deficient diet as for rats on the normal diet and these numbers were not affected by treatment with morphine. In contrast, numbers of neurons that expressed the calcium-binding protein parvalbumin, which is a marker interneurons that express the inhibitory neurotransmitter gamma-amino butyric acid (GABAergic neurons) were decreased for wild-type (Wt) rats on the VA deficient diet and for Wt rats treated with morphine. In addition, parvalbumin+ neurons were also decreased for Tg rats on a normal diet but increased to normal levels when these animals were placed on the VA deficient diet and treated with morphine. Analysis of expression of HIV regulatory proteins vif, vpr, and nef in frontal cortex and adjacent subcortical white matter showed that expression of these genes was increased in the Tg rat on the normal diet as compared to a control housekeeping gene. Morphine treatment suppressed expression of the HIV genes; however, expression was increased by VA deficiency and by morphine plus deficiency. These studies therefore suggest that VA deficiency, opioid and HIV infection alone and in combination may either suppress neuronal metabolic activity or induce metabolic stress, resulting in the observed changes in levels of parvalbumin expression. The specific mechanisms that underlie these effects require further study.

Skin lesions commonly affect AIDS patients. The pathogenesis of certain dermatologic disorders primarily associated to HIV-1 is unclear, and better forms of therapy for these conditions need to be discovered. Transgenic animal models represent a novel approach for the study of these disorders and for the quest of more effective forms of treatment.Characterize this HIV-1 transgenic rat as a model to study skin diseases related to HIV/AIDS.A transgenic rat was developed, using an HIV-1 construct with deleted gag and pol genes. Morphological and genotypical evaluations were followed by cytokine profile characterization of the lesions.We report the characterization of a colony of HIV-1 transgenic rats that developed skin lesions in a frequency of 22.5%. Cutaneous expression of functional HIV-1 transgenes correlated precisely with the severity of the phenotype. In early stages, rats manifested localized areas of xerosis and dispersed papulosquamous lesions. These hyperplastic manifestations were observed in conjunction with an increased epidermal expression of tat protein and a Th1/Th2 profile of cytokines. As the lesions progressed, they formed inflammatory plaques that subsequently ulcerated. Histologically, these lesions displayed a profound lymphocytic infiltrate, epidermal necrosis, and a marked increase of both Th1 and Th2 derived cytokines. Moreover, the presence of circulating IgG antibodies against HIV-1 gp120 was detected.This animal model as other HIV-1 transgenic mice described in the past, is not able to fully explain the myriad of skin findings that can occur in HIV-infected humans; however, it represents a potential animal model system for the study of immune-mediated inflammatory skin diseases.

A novel HIV-1 transgenic rat model of childhood HIV-1–associated nephropathy. Background A characteristic finding of human immunodeficiency virus (HIV)-associated nephropathy (HIVAN) is the presence of heavy proteinuria, focal or global glomerulosclerosis, and microcystic tubular dilatation leading to renal enlargement, and rapid progression to end-stage renal disease (ESRD). Methods We have recently developed the first HIV-1 transgenic rat model that carry a noninfectious HIV-1 DNA construct lacking 3.1 kb of sequence overlapping the gag and pol sequences, and develop many of the clinical lesions seen in HIV-infected patients, including HIVAN. To gain further insight into the pathogenesis of childhood HIVAN, we followed the clinical and renal pathologic outcome of 165 HIV-1 transgenic (HIV-Tg) rats and their respective control littermates for a period of 18 months. Results HIV-1 Tg rats progressively developed proteinuria and renal histologic lesions similar to those seen in children with HIVAN, leading to chronic renal failure. By in situ hybridization, HIV-1 genes were detected in glomerular and tubular epithelial cells and infiltrating mononuclear cells, which also expressed the HIV-1 envelop protein gp120. The development of HIVAN was associated with the accumulation of basic fibroblast growth factor (bFGF) in the kidney. Conclusion These data support the notion that HIV-1 plays a direct role in the pathogenesis of HIVAN, by affecting the function and growth of renal epithelial cells, inducing the recruitment of mononuclear cells, and accumulating bFGF in the kidney, even in the absence of viral replication. These rats may provide an excellent model system to study the pathogenesis of childhood HIVAN.

We report, to our knowledge, the first HIV type 1 (HIV-1) transgenic (Tg) rat. Expression of the transgene, consisting of an HIV-1 provirus with a functional deletion of gag and pol , is regulated by the viral long terminal repeat. Spliced and unspliced viral transcripts were expressed in lymph nodes, thymus, liver, kidney, and spleen, suggesting that Tat and Rev are functional. Viral proteins were identified in spleen tissue sections by immunohistochemistry and gp120 was present in splenic macrophages, T and B cells, and in serum. Clinical signs included wasting, mild to severe skin lesions, opaque cataracts, neurological signs, and respiratory difficulty. Histopathology included a selective loss of splenocytes within the periarterial lymphoid sheath, increased apoptosis of endothelial cells and splenocytes, follicular hyperplasia of the spleen, lymphocyte depletion of mesenteric lymph nodes, interstitial pneumonia, psoriatic skin lesions, and neurological, cardiac, and renal pathologies. Immunologically, delayed-type hypersensitivity response to keyhole limpet hemocyanin was diminished. By contrast, Ab titers and proliferative response to recall antigen (keyhole limpet hemocyanin) were normal. The HIV-1 Tg rat thus has many similarities to humans infected with HIV-1 in expression of viral genes, immune-response alterations, and pathologies resulting from infection. The HIV-1 Tg rat may provide a valuable model for some of the pathogenic manifestations of chronic HIV-1 diseases and could be useful in testing therapeutic regimens targeted to stages of viral replication subsequent to proviral integration.

Organogenesis has been given increasing attention in the fields of biomedical and bioengineering. However, the mechanism for a succession process as complex as embryogenesis remains largely unknown. Based on our previous discoveries, liquid crystal may play a crucial role in organogenesis. Here, our results demonstrated that LC droplets were distributed on the pleural area, the bronchus and bronchiole in the developing lung. The lung liquid crystal droplets are capable of phase transitions between liquid crystal, crystal, and isotropic phases which are dependent on the rate of temperature change as previously reported in liver, kidney and other major tissues of the embryo.

Massive liquid crystal droplets (LCDs) have been reported in early embryogenesis and implicated in pathological progression of human diseases. The presence of LCDs has even been established as an effective diagnostic hallmark of Fabry-Anderson's disease. In this study, we report the presence of LCDs, identified by established thermal stage phase transition methods, in sputum collected during the recovery phase of respiratory infection by gram-positive bacteria. This finding provides additional insight on the breadth of liquid crystal presence in human pathology. Further study on the formation of these LCDs may lead to new perspectives on post-infection removal of infectious agents.

As an essential molecule in Wnt/β-catenin signaling, β-Catenin plays a crucial role in the decision making for tissue differentiation in embryogenesis and pathogenesis. The signaling was implicated in the development of skin. In mouse skin, the deferential fate of the skin stem cell depends on β-catenin, which organizes stem cells into follicular or epidermal lineages. These analyses indicate that Wnt/β-catenin signaling should also function in the development and differentiation of human embryonic stem cell. To study the function of β-catenin in early differentiation of human stem cells, we cultured H9 stem cell and aggregated them into embryoid bodies (EB). In this study, we revealed that in early EBs some guarding cells were first differentiated from EB stem cell aggregates. These early differentiated cells for guarding epithelial cells have strongest expression of β-catenin within EB. These cells were flattened on the surface of EB, covering the surface by connections formed through protein interactions. At certain confocal sections of EB, instead of a round boundary, a polygonal boundary was observed even though the EB appeared round under conventional microscope. In these polygonal boundaries, β-catenin positive guarding epithelial cells were positioned on every corner of the polygon. In the inner portion of the EB, undifferentiated β-catenin positive cells express β-catenin in the nucleus. As the initially simple shape of EB becomes more and more intricate during development, we revealed that more β-catenin positive cells were also observed in this complex structure. Based on these results, we predicted β-catenin to play different roles while guarding epithelial cells or undifferentiated stem cells in the inner portion of EB in in vitro culture system. Phosphorylation of β-catenin may be a critical factor for fate determination of the human stem cell.

Calcium carbonate is often used as an efficient antacid that absorbs and neutralizes stomach acid while providing calcium for healthy bones. Taking advantage of the lack of adverse side effects of calcium, new drug delivery systems consisting of drug-supported spherical microparticles are being developed. We have reported in our previous studies that a natural process producing calcium carbonate microparticles can be found during avian development. These natural systems provide inspiration for designing more efficient microparticle facilitated drug-delivery systems. In this study, the formation and re-absorption of calcium carbonate crystals were tracked during Gallina N. meleagris embryogenesis and early postnatal development. The study demonstrated that the formation of calcium carbonate microparticles, as calcium is transferred from the eggshell into the egg sac, is a process of calcium preservation. X-ray diffraction showed that calcium carbonate crystal is mainly preserved in the vaterite isoform. Calcium incorporated into the yolk sac during this process can be easily assimilated as necessary during postnatal development. Eons of evolution have yielded a calcium preservation process that produces an iso-form of crystalline calcium most readily absorbed by the organism. Our previous results indicate that this biological system is likely a lyotropic process, the method that is currently being used for the production of microparticle drug delivery systems. In this work, our data suggests that calcium carbonate crystal can also initiate its crystallization from the center of liquid crystal, recognizable by a chimeric thermal phase transition. Our work provides valuable information for designing more efficient microparticle for drug-delivery.

Maltese-cross appearance of birefringent molecule configuration has become a typical diagnostic characteristic used to evaluate the kidney complications of Anderson-Fabry disease, an Xq22.1-linked ...

The yolk sac equipped with vitelline fluid, plays a crucial role in supplying nourishment to the developing chicken embryo during embryonic and early postnatal development. The absorption and utilization of calcium in embryogenesis has been investigated for years. However, the preservation process of the calcium as it is transported through the chorioallantois membrane during embryogenesis remains largely unknown. In this study, we demonstrated that abundant liquid crystal droplets (LCLD) subsist with calcium carbonate vaterite crystals (CCVC) in the yolk sac, revealing a possible function of LCDL in CCVC crystallization.

INTRODUCTION. Apoptosis is believed to play a major role in the progressive loss of CD4 + T cells, and other cell types in AIDS. Several studies support the theory that HIV-1 gene products may be the causative factor in the initiation of cell death (1-3). Moreover, post mortem studies reveal apoptotic cells in many tissues. Identification of mechanisms for the production of apoptosis in animal models of AIDS may clarify AIDS related cell death. A new model, developed at IHV for the study of AIDS related pathology is the HIV-1 Transgenic Rat. This model is unique among transgenic models in that measurable levels of Gp-120 have been identified in the serum and in spleenocyte lysates (4). In this study, we have characterized the location of HIV-1 transgene (GP120, NEF, TAT) expression in the spleen by means of immunocytochemistry. Moreover, identification of cells undergoing apoptosis was made in adjacent sections. The localization of HIV-1 gene products and the identification of apoptosis in this new animal model of AIDS could give insight in the mechanisms of HIV related cell lose.

INTRODUCTION. Neurological abnormalities of the peripheral (PNS) and central nervous system continue to cause debilitating symptoms in AIDS patients despite advances in antiviral therapy (1). How HIV-1 mediates PNS damage is unknown. Our understanding is limited by the lack of model systems in which HIV/PNS pathology can be studied. Studies on the recently developed HIV-1 transgenic rat (HIV-1TgR) reveal that a subset of these animals displays severe neurological signs. These symptoms include complete or partial paralysis, difficulties in walking and sensitivity to touch. Progressive skeletal muscle mass loss with increasing severity of motor symptoms occurs over time. These clinical observations suggest that morphological changes to the nerve might be found. Peripheral nerve was examined in a group of HIV-1 TGRs which displayed neurologic symptoms. By characterizing the abnormalities in this model, it may be possible to develop theories on pathogenesis relevant to treatment.

INTRODUCTION. Special attention is focused on the central nervous system (CNS) in AIDS because of the debilitating symptoms and unique neuropathology. Anti- viral therapy has been effective in treating many of the symptoms of AIDS. But the CNS and PNS can continue to display debilitating symptoms even when the patient is on antiviral therapy (1). Motor abnormalities and atrophy of skeletal muscle are two PNS problems that continue to resist treatment. In order to understand the disease process and to develop new therapies, animal model systems are needed (2). The recently developed HIV-1 Transgenic Rat (HIV-1 TgR) displays many neurological symptoms of AIDS (3). These symptoms include muscular wasting, weakness, difficulties in gait, and paralysis. Examination of the peripheral nerve has revealed degeneration of the axons and focal demyelination. The muscular changes may be secondary to this nerve pathology or myopathic mechanisms may be operational. The muscle in these animals was examined by histologic means. By identifying the type of degeneration it may be possible to eventual study the effect of growth factors or therapeutics. METHODS. HIV-1TGRs were constructed using transgenic protocols. The pronuclei were microinjected with an HIV-1-gag-pol-pEVd 1443 clone in which the SphI and Bal1 fragment that contained the 3’ gag region and 5’ pol region of the infectious proviral DNA pNL4.3 clone was removed. This produced a non-infectious model. Gp-120 is found in their serum. Immunocytochemistry to Gp-120, TAT and Nef localized the viral products to the lymphoid tissue. Animals were observed for neurologic abnormalities. Their clinical symptoms were recorded over time. Both nerve and muscle were removed at necropsy for histologic analysis. Tissues were prepared for light and electron microscopy. The special stains used were H&E, NADH, ATPase, lymphocyte markers, and ApopTag. Thick sections stained with Toluidine Blue. RESULTS. Depending on the muscle studied one could observe mild changes (inflammatory changes, and apoptosis to endothelial cells) to severe end stage changes (fatty replacement of muscle, phagocytosis of myocytes and necrosis). The hind limb muscle typically displayed the most marked changes. Intermediate changes include atrophic, angulated fibers (Fig.1), hypertropic fibers surrounded fat, increased connective tissue and internal nuclei (Fig. 2).