Effect of coronary disease characteristics on prognostic relevance of residual ischemia after stent implantation

Background

Although residual ischemia after revascularization is an important predictor of future cardiovascular events, its sensitivity and specificity to predict clinical events were relatively low, and data on which coronary disease characteristics affect prognostic implications of residual ischemia are limited.

Purpose

We aimed to investigate the influence of coronary disease characteristics on prognostic implications of residual ischemia after percutaneous coronary intervention (PCI).

Methods

This study included 1,476 patients with drug-eluting stent implantation and available pre- and post-PCI fractional flow reserve (FFR) measurements from the international post-PCI FFR registry (NCT04012281). Residual ischemia was defined as post-PCI FFR ≤0.80. Coronary disease characteristics with significant interaction hazard ratios (HRs) for clinical outcomes with residual ischemia were defined as interaction characteristics with residual ischemia (ICwRI). The primary outcome was target vessel failure (TVF)–a composite of cardiac death, target vessel myocardial infarction, and target vessel revascularization–at 2 years.

Results

The mean pre- and post-PCI FFR were 0.68±0.11 and 0.87±0.07, respectively. The 203 vessels (13.8%) with residual ischemia had higher risks of TVF compared to that for post-PCI FFR >0.80 (HR 2.45, 95% confidence interval [CI] 1.50–4.00, P<0.001). Among pre- and post-PCI angiographic characteristics, ICwRI with a significant interaction HR with residual ischemia (P<0.10) included lesion length ≥40 mm, pre-PCI SYNTAX score >17, and pre-PCI FFR ≤0.62 (Table). Each ICwRI had a direct prognostic effect not mediated by residual ischemia in mediation analysis. The association between an increased TVF risk and residual ischemia differed according to the number of ICwRI (p-for-interaction <0.001). It was significant in patients with 0 or 1 ICwRI (HR 3.48, 95% CI 2.01–6.00, P<0.001) but not in those with ≥2 ICwRI (HR 0.60, 95% CI 0.18–2.03, P=0.41) (Figure A). Compared to the residual ischemia group, patients without residual ischemia and those with 0 or 1 ICwRI showed a significantly lower risk of TVF (HR 0.32, 95% CI 0.19–0.54, P<0.001), but those with ≥2 ICwRI had a similar risk of TVF as the residual ischemia group (HR 1.08, 95% CI 0.57–2.01, P=0.819) (Figure B). The prognostic impact of ≥2 ICwRI in patients without residual ischemia was consistent in all subgroups with different clinical characteristics.

Conclusions

Coronary disease characteristics including lesion length, SYNTAX score, and pre-PCI FFR affected the prognostic implications of residual ischemia. This prognostic relevance was attenuated in patients with multiple interacting characteristics. Therefore, comprehensive assessment of coronary disease characteristics with post-procedural coronary physiology can help better risk stratification and appropriate treatment planning after revascularization.

Funding Acknowledgement

Type of funding sources: None.

Expression of Cellular Receptors in the Ischemic Hemisphere of Mice with Increased Glucose Uptake

Many previous studies have shown reduced glucose uptake in the ischemic brain. In contrast, in a permanent unilateral common carotid artery occlusion (UCCAO) mouse model, our pilot experiments using 18F-fluorodeoxyglucose positron emission tomography (FDG PET) revealed that a subset of mice exhibited conspicuously high uptake of glucose in the ipsilateral hemisphere at 1 week post-occlusion (asymmetric group), whereas other mice showed symmetric uptake in both hemispheres (symmetric group). Thus, we aimed to understand the discrepancy between the two groups. Cerebral blood flow and histological/metabolic changes were analyzed using laser Doppler flowmetry and immunohistochemistry/Western blotting, respectively. Contrary to the increased glucose uptake observed in the ischemic cerebral hemisphere on FDG PET (p<0.001), cerebral blood flow tended to be lower in the asymmetric group than in the symmetric group (right to left ratio [%], 36.4±21.8 vs. 58.0±24.8, p=0.059). Neuronal death was observed only in the ischemic hemisphere of the asymmetric group. In contrast, astrocytes were more activated in the asymmetric group than in the symmetric group (p<0.05). Glucose transporter-1, and monocarboxylate transporter-1 were also upregulated in the asymmetric group, compared with the symmetric group (p<0.05, respectively). These results suggest that the increased FDG uptake was associated with relatively severe ischemia, and glucose transporter-1 upregulation and astrocyte activation. Glucose metabolism may thus be a compensatory mechanism in the moderately severe ischemic brain.

Insulin-like Growth Factor-1 Receptor Dictates Beneficial Effects of Treadmill Training by Regulating Survival and Migration of Neural Stem Cell Grafts in the Injured Spinal Cord

Survival and migration of transplanted neural stem cells (NSCs) are prerequisites for therapeutic benefits in spinal cord injury. We have shown that survival of NSC grafts declines after transplantation into the injured spinal cord, and that combining treadmill training (TMT) enhances NSC survival via insulin-like growth factor-1 (IGF-1). Here, we aimed to obtain genetic evidence that IGF-1 signaling in the transplanted NSCs determines the beneficial effects of TMT. We transplanted NSCs heterozygous (+/-) for Igf1r, the gene encoding IGF-1 receptor, into the mouse spinal cord after injury, with or without combining TMT. We analyzed the influence of genotype and TMT on locomotor recovery and survival and migration of NSC grafts. In vitro experiments were performed to examine the potential roles of IGF-1 signaling in the migratory ability of NSCs. Mice receiving +/- NSC grafts showed impaired locomotor recovery compared with those receiving wild-type (+/+) NSCs. Locomotor improvement by TMT was more pronounced with +/+ grafts. Deficiency of one allele of Igf1r significantly reduced survival and migration of the transplanted NSCs. Although TMT did not significantly influence NSC survival, it substantially enhanced the extent of migration for only +/+ NSCs. Cultured neurospheres exhibited dynamic motility with cytoplasmic protrusions, which was regulated by IGF-1 signaling. IGF-1 signaling in transplanted NSCs may be essential in regulating their survival and migration. Furthermore, TMT may promote NSC graft-mediated locomotor recovery via activation of IGF-1 signaling in transplanted NSCs. Dynamic NSC motility via IGF-1 signaling may be the cellular basis for the TMT-induced enhancement of migration.

An injectable hydrogel enhances tissue repair after spinal cord injury by promoting extracellular matrix remodeling

The cystic cavity that develops following injuries to brain or spinal cord is a major obstacle for tissue repair in central nervous system (CNS). Here we report that injection of imidazole-poly(organophosphazenes) (I-5), a hydrogel with thermosensitive sol–gel transition behavior, almost completely eliminates cystic cavities in a clinically relevant rat spinal cord injury model. Cystic cavities are bridged by fibronectin-rich extracellular matrix. The fibrotic extracellular matrix remodeling is mediated by matrix metalloproteinase-9 expressed in macrophages within the fibrotic extracellular matrix. A poly(organophosphazenes) hydrogel lacking the imidazole moiety, which physically interacts with macrophages via histamine receptors, exhibits substantially diminished bridging effects. I-5 injection improves coordinated locomotion, and this functional recovery is accompanied by preservation of myelinated white matter and motor neurons and an increase in axonal reinnervation of the lumbar motor neurons. Our study demonstrates that dynamic interactions between inflammatory cells and injectable biomaterials can induce beneficial extracellular matrix remodeling to stimulate tissue repair following CNS injuries.

The cystic cavity that develops following injuries to brain or spinal cord is a major obstacle. Here the authors show an injection of imidazole poly(organophosphazenes), a hydrogel with thermosensitive sol–gel transition behavior, almost completely eliminates cystic cavities in a clinically relevant rat spinal cord injury model.

Stem Cell-Based Cell Therapy for Spinal Cord Injury

Traumatic injuries to the spinal cord lead to severe and permanent neurological deficits. Although no effective therapeutic option is currently available, recent animal studies have shown that cellular transplantation strategies hold promise to enhance functional recovery after spinal cord injury (SCI). This review is to analyze the experiments where transplantation of stem/progenitor cells produced successful functional outcome in animal models of SCI. There is no consensus yet on what kind of stem/progenitor cells is an ideal source for cellular grafts. Three kinds of stem/progenitor cells have been utilized in cell therapy in animal models of SCI: embryonic stem cells, bone marrow mesenchymal stem cells, and neural stem cells. Neural stem cells or fate-restricted neuronal or glial progenitor cells were preferably used because they have clear capacity to become neurons or glial cells after transplantation into the injured spinal cord. At least a part of functional deficits after SCI is attributable to chronic progressive demyelination. Therefore, several studies transplanted glial-restricted progenitors or oligodendrocyte precursors to target the demyelination process. Directed differentiation of stem/progenitor cells to oligodendrocyte lineage prior to transplantation or modulation of microenvironment in the injured spinal cord to promote oligodendroglial differentiation seems to be an effective strategy to increase the extent of remyelination. Transplanted stem/progenitor cells can also contribute to promoting axonal regeneration by functioning as cellular scaffolds for growing axons. Combinatorial approaches using polymer scaffolds to fill the lesion cavity or introducing regeneration-promoting genes will greatly increase the efficacy of cellular transplantation strategies for SCI.

Molecular and cellular changes in the lumbar spinal cord following thoracic injury: regulation by treadmill locomotor training

Traumatic spinal cord injury (SCI) often leads to debilitating loss of locomotor function. Neuroplasticity of spinal circuitry underlies some functional recovery and therefore represents a therapeutic target to improve locomotor function following SCI. However, the cellular and molecular mechanisms mediating neuroplasticity below the lesion level are not fully understood. The present study performed a gene expression profiling in the rat lumbar spinal cord at 1 and 3 weeks after contusive SCI at T9. Another group of rats received treadmill locomotor training (TMT) until 3 weeks, and gene expression profiles were compared between animals with and without TMT. Microarray analysis showed that many inflammation-related genes were robustly upregulated in the lumbar spinal cord at both 1 and 3 weeks after thoracic injury. Notably, several components involved in an early complement activation pathway were concurrently upregulated. In line with the microarray finding, the number of microglia substantially increased not only in the white matter but also in the gray matter. C3 and complement receptor 3 were intensely expressed in the ventral horn after injury. Furthermore, synaptic puncta near ventral motor neurons were frequently colocalized with microglia after injury, implicating complement activation and microglial cells in synaptic remodeling in the lumbar locomotor circuitry after SCI. Interestingly, TMT did not influence the injury-induced upregulation of inflammation-related genes. Instead, TMT restored pre-injury expression patterns of several genes that were downregulated by injury. Notably, TMT increased the expression of genes involved in neuroplasticity (Arc, Nrcam) and angiogenesis (Adam8, Tie1), suggesting that TMT may improve locomotor function in part by promoting neurovascular remodeling in the lumbar motor circuitry.

Real-time pulse measurement of nano-scale field effect transistors: cancellation of displacement current and extraction of coupling capacitance

Real-time pulse measurements of nano-scale field effect transistors (FETs) are reported. We demonstrate the direct monitoring of the real-time current of bottom-up assembled silicon nanowire FET and top-down fabricated gate-all-around silicon nanowire FET, both with the diameter of approximately 50 nm. We demonstrate that the displacement current can be cancelled out from the measured pulse responses. On the other hand, the displacement current also can be utilized to obtain the coupling capacitance between the gate and source of the FETs.

Spatial and temporal correlation in progressive degeneration of neurons and astrocytes in contusion-induced spinal cord injury

BACKGROUND

Traumatic spinal cord injury (SCI) causes acute neuronal death followed by delayed secondary neuronal damage. However, little is known about how microenvironment regulating cells such as microglia, astrocytes, and blood inflammatory cells behave in early SCI states and how they contribute to delayed neuronal death.

METHODS

We analyzed the behavior of neurons and microenvironment regulating cells using a contusion-induced SCI model, examining early (3-6 h) to late times (14 d) after the injury.

RESULTS

At the penumbra region close to the damaged core (P1) neurons and astrocytes underwent death in a similar spatial and temporal pattern: both neurons and astrocytes died in the medial and ventral regions of the gray matter between 12 to 24 h after SCI. Furthermore, mRNA and protein levels of transporters of glutamate (GLT-1) and potassium (Kir4.1), functional markers of astrocytes, decreased at about the times that delayed neuronal death occurred. However, at P1 region, ramified Iba-1+ resident microglia died earlier (3 to 6 h) than neurons (12 to 24 h), and at the penumbra region farther from the damaged core (P2), neurons were healthy where microglia were morphologically activated. In addition, round Iba-1/CD45-double positive monocyte-like cells appeared after neurons had died, and expressed phagocytic markers, including mannose receptors, but rarely expressed proinflammatory mediators.

CONCLUSION

Loss of astrocyte function may be more critical for delayed neuronal death than microglial activation and monocyte infiltration.

Effects of the mixing ratio of the CaAl12O19:mn and Zn2SiO4:mn color-conversion layer on the color tunable emissions of white organic light-emitting devices

The optical properties of white organic light-emitting devices (WOLEDs) fabricated utilizing a CaAl12O19:Mn and Zn2SiO4:Mn phosphor layer were investigated. X-ray diffraction patterns for CaAl12O19:Mn and Zn2SiO4:Mn phosphors showed that Mn ions in the CaAl12O19:Mn phosphors were completely substituted into Ca ions and that Mn ions in the Zn2SiO4:Mn phosphors were completely substituted into Zn ions. Field emission scanning electron microscopy images showed that the size of the CaAl12O19:Mn phosphor was approximately between 0.1 and 3 microm, and that the size of the Zn2SiO4:Mn phosphor was smaller than 7 microm. The color coordinates of the electroluminescence spectra for WOLEDs with phosphor thicknesses of 0.25 and 0.35 mm shifted to the white emission side because the generated blue light from the blue OLEDs combined with the red and green lights was converted by the CaAl12O19:Mn and the Zn2SiO4:Mn phosphor down-conversion layers.

Fabrication and radio frequency characterization of carbon nanotube field effect transistor: evidence of quantum capacitance

We fabricated an radio frequency (RF) carbon nanotube field effect transistor (CNTFET) whose electrode shapes were standard RF designed ground-signal-ground (GSG)-type pads. The S-parameters measured from our RF CNTFET in the frequency range up to 6 GHz were fitted with an RF equivalent circuit, and the extracted gate capacitance was shown to be the capacitance value of the series combination of the electrostatic capacitance and the quantum capacitance. The effect of the channel resistance and the kinetic inductance was also discussed.

Ex vivo VEGF delivery by neural stem cells enhances proliferation of glial progenitors, angiogenesis, and tissue sparing after spinal cord injury

The present study was undertaken to examine multifaceted therapeutic effects of vascular endothelial growth factor (VEGF) in a rat spinal cord injury (SCI) model, focusing on its capability to stimulate proliferation of endogenous glial progenitor cells. Neural stem cells (NSCs) can be genetically modified to efficiently transfer therapeutic genes to diseased CNS. We adopted an ex vivo approach using immortalized human NSC line (F3 cells) to achieve stable and robust expression of VEGF in the injured spinal cord. Transplantation of NSCs retrovirally transduced to overexpress VEGF (F3.VEGF cells) at 7 days after contusive SCI markedly elevated the amount of VEGF in the injured spinal cord tissue compared to injection of PBS or F3 cells without VEGF. Concomitantly, phosphorylation of VEGF receptor flk-1 increased in F3.VEGF group. Stereological counting of BrdU+ cells revealed that transplantation of F3.VEGF significantly enhanced cellular proliferation at 2 weeks after SCI. The number of proliferating NG2+ glial progenitor cells (NG2+/BrdU+) was also increased by F3.VEGF. Furthermore, transplantation of F3.VEGF increased the number of early proliferating cells that differentiated into mature oligodendrocytes, but not astrocytes, at 6 weeks after SCI. F3.VEGF treatment also increased the density of blood vessels in the injured spinal cord and enhanced tissue sparing. These anatomical results were accompanied by improved BBB locomotor scores. The multifaceted effects of VEGF on endogenous gliogenesis, angiogenesis, and tissue sparing could be utilized to improve functional outcomes following SCI.

The land use plan and water quality prediction for the Saemangeum reclamation project

As the final closure of the world's longest sea dike of 33 km, the use of the Saemangeum reclaimed land becomes an issue in Korea. The Korean government has proclaimed that the Saemangeum Reclamation Project will be handled in an environmentally friendly manner but its effect on the water quality of reservoirs has always been controversial. This study was conducted to estimate the water quality of the Saemangeum reservoir using WASP5 according to the new land use plan adopted in 2007. Predictions on water quality shows that Dongjin reservoir would meet the standards for COD, T-P, and Chl-a if the wastewater from the Dongjin region was properly managed. However, T-P and Chl-a in Mangyeong reservoir would exceed the standards even without releasing the treated wastewater into the reservoir. With further reductions of 20% for T-P and Chl-a from the mouth of Mangyeong river, the water quality standards in the reservoir were achieved. This means that additional schemes, as well as water quality management programs established in the Government Master Plan in 2001, should be considered. Although the Saemangeum reservoir would manage to achieve the standards, it will enter a eutrophic state due to the high concentration of nutrients.

Predictive factors for nephritis, relapse, and significant proteinuria in childhood Henoch-Schönlein purpura

OBJECTIVE

To identify predictive factors for nephritis, relapse, and significant proteinuria in childhood Henoch-Schönlein purpura (HSP).

METHODS

Two hundred and six consecutive patients with HSP (93 female, 113 male), followed up at a single centre between 1996 and 2001, were analysed retrospectively. They were regularly monitored for clinical and laboratory parameters for renal sequelae and relapse.

RESULTS

Nephritis was seen in 78 patients (38%), relapse in 52 (25%), and significant proteinuria in 39 (19%). In univariate analysis, an older age at onset (>10 years), persistent purpura, severe bowel angina, and relapse were identified as factors associated with nephritis and significant proteinuria. Relapse-related factors were an older age, persistent purpura, severe bowel angina, and leucocytosis. Logistic regression analysis showed that nephritis was significantly associated with an older age, persistent purpura, and relapse, and significant proteinuria was closely related to severe bowel angina and relapse.

CONCLUSION

We identified some predictors for nephritis, relapse, and significant proteinuria in childhood HSP, and close attention should be paid to those patients with the risk factors, such as an older age at onset, persistent purpura, severe bowel angina, and relapse.

Overexpression of the prostaglandin E2 receptor EP2 results in enhanced skin tumor development

We previously showed that the EP2 knockout mice were resistant to chemically induced skin carcinogenesis. The purpose of this study was to investigate the role of the overexpression of the EP2 receptor in mouse skin carcinogenesis. To determine the effect of overexpression of EP2, we used EP2 transgenic (TG) mice and wild-type (WT) mice in a DMBA (7,12-dimethylbenz[alpha]anthracene)/TPA (12-O-tetradecanoylphorbol-13-acetate) two-stage carcinogenesis protocol. EP2 TG mice developed significantly more tumors compared with WT mice. Overexpression of the EP2 receptor increased TPA-induced keratinocyte proliferation both in vivo and in vitro. In addition, the epidermis of EP2 TG mice 48 h after topical TPA treatment was significantly thicker compared to that of WT mice. EP2 TG mice showed significantly increased cyclic adenosine monophosphate levels in the epidermis after prostaglandin E2 (PGE2) treatment. The inflammatory response to TPA was increased in EP2 TG mice, as demonstrated by an increased number of macrophages in the dermis. Tumors and 7 x TPA-treated and DMBA-TPA-treated (6 weeks) skins from EP2 TG mice produced more blood vessels than those of WT mice as determined by CD-31 immunostaining. Vascular endothelial growth factor (VEGF) protein expression was significantly increased in squamous cell carcinoma (SCC) samples from EP2 TG mice compared that of WT mice. There was, however, no difference in the number of apoptotic cells in tumors from WT and EP2 TG mice. Together, our results suggest that the overexpression of the EP2 receptor plays a significant role in the protumorigenic action of PGE2 in mouse skin.

Oligodendroglia in the avian retina: immunocytochemical demonstration in the adult bird

Immunohistochemical techniques were used in conjunction with an avian-specific probe for oligodendrocyte (OLG) marker, the antibody for transferrin binding protein (TfBP), to study the characteristics and distribution of OLGs in the retina of chickens and quails. For comparison, other antibodies such as myelin basic protein, Rip, and those for labeling Müller cells and microglia were used. A large population of OLGs was found to be distributed throughout the retina, with the distinct pattern of a central-to-peripheral gradient. It was possible to detect a spectrum of OLG morphology that bore a resemblance to the subtype of the mammalian central nervous system. In addition to these mature OLGs, limited numbers of TfBP-positive (TfBP(+)) cells with the morphology of immature OLGs were found in the immediate vicinity of the optic head. The majority of OLGs appeared in the ganglion cell layer throughout the retina, whereas OLGs in the nerve fiber layer were seen mainly in the central zone of the retina, near the optic nerve head. Double-labeling experiments showed that OLGs were associated with myelin only in the central region, where the majority of retinal OLGs occurred, but not toward the periphery of the retina. The present study is the first comprehensive analysis of the morphological features and spatial distribution of OLGs in the adult avian retina and provides in vivo evidence for the existence of a substantial population of both mature and immature OLGs in the retina of adult birds. The putative functions of TfBP(+) OLGs including myelination and the tropic role of the ganglion cells are discussed in conjunction with the physical properties of TfBP and structural characteristics of the avascular retina of birds.

Suppression of tumor cell growth both in nude mice and in culture by n-3 polyunsaturated fatty acids: mediation through cyclooxygenase-independent pathways

Dietary n-3 polyunsaturated fatty acids (PUFAs), as compared with n-6 PUFAs, suppress cellular production of prostaglandins and tumor cell growth both in vitro and in vivo. However, the mechanism by which n-3 PUFAs suppress tumor growth is not understood. We investigated whether the suppression of tumor cell growth by dietary n-3 PUFAs is mediated through inhibition of cyclooxygenase (COX). A colon tumor cell line, HCT-116, that does not express COX was stably transfected with the constitutively expressed COX-1 or the inducible COX-2 cDNA using a retroviral transfection and infection system. Athymic nude mice transplanted with the cells expressing enzymatically active COX were fed isocaloric diets containing either safflower oil or fish oil for 2 weeks before the start of the experiment and for an additional 21 days after transplantation. Both tumor volume and tumor burden (tumor volume/body weight) were significantly reduced in mice fed the fish oil diet as compared with safflower oil-fed mice. This reduction occurred even in control mice that received injections with cells infected with the retroviral vector without COX-1 or COX-2 cDNA. The growth of tumor cells expressing COX was not different from the growth of those transfected with the vector alone in the nude mice and in soft agar. N-3 PUFAs, as compared with linoleic acid, also inhibited the growth of these cells in culture. This growth inhibition by n-3 PUFAs was not affected by COX-1 or COX-2 overexpression. Contrary to general belief, these results indicate that the suppression of tumor growth by dietary n-3 PUFAs is mediated through COX-independent pathways.

MR imaging of shaken baby syndrome manifested as chronic subdural hematoma

Shaken baby syndrome (SBS) is a form of child abuse that can cause significant head injuries, of which subdural hematoma (SDH) is the most common manifestation. We report the MRI findings of chronic SDH in three cases of SBS, involving two-, three- and eight-month-old babies. The SDH signal was mostly low on T1-weighted images and high on T2-weighted images, suggesting chronic SDH. In chronic SDH, a focal high signal on T1-weighted images was also noted, suggesting rebleeding. Contrast-enhanced MRI revealed diffuse dural enhancement.

Reconstituted basement membrane induces glandular-like morphogenesis but no difference in ACTH synthesis of anterior pituitary cells

Basement membrane, a thin extracellular matrix, promotes tissue integrity and differentiated phenotype. This study was performed in order to investigate the effect of basement membrane components on adrenocorticotropin (ACTH) synthesis and to observe its relationship with cell morphology. Rat anterior pituitary cells were cultured on plastic culture plate coated with either Matrigel or poly-D-lysine. Phase-contrast microscopy and scanning electron microscopy showed that cells cultured on Matrigel appeared as a three-dimensional glandular-like cell aggregate, while those cultured on plastic showed a flat, confluent monolayer. Reverse-transcription polymerase chain reaction (RT-PCR) and Northern blot analysis revealed that ACTH synthesis in the Matrigel culture was not significantly different from that in the plastic culture. Our results suggest that the relationship between the morphological changes caused by cell-substrate interaction and pituitary hormone synthesis does not exist in all pituitary cell types and that other factors associated with cell-substrate interaction influence the hormone synthesis of some pituitary cells.

Immunocytochemical localization of neuronal and inducible nitric oxide synthase in the retina of zebrafish, Brachydanio rerio

Several previous studies have revealed the distribution of neuronal nitric oxide synthase (nNOS) and inducible nitric oxide synthase (iNOS) in the retina of various species. However, nothing has been reported on the nNOS and iNOS expression in zebrafish retina, even though it has been used as an effective model for developmental studies. In this study on nNOS and iNOS immunoreactivity (IR) in the zebrafish retina, iNOS-IR signals were detected in the ganglion cell layer (GC), the inner plexiform layer (IP), the outer plexiform layer (OP) and the photoreceptor layer (PR). nNOS-IR signals were also intensely detected in the GC, IP, OP and PR. These signals were very similar to the iNOS-IR signals, except for some minor differences in relative intensities. This could be explained by the speculation that the synthesis of nitric oxide by iNOS may represent a compensatory mechanism in the absence of nNOS. We described for the first time the distribution of nNOS and iNOS-IR cells in zebrafish retina. This could provide the basis for further study on the nNOS and iNOS properties of zebrafish retina.

Activation of microglia in kainic acid induced rat retinal apoptosis

We applied a variety of methods to follow the course of kainic acid (KA) induced retinal apoptosis, especially with regard to the spatial and temporal aspects. At 24 h after KA injection, a massive cell increase, which showed terminal transferase-mediated dUTP nick-end-labeling technique positive signals, was observed in all of the retinal layers, with the exception of the outer nuclear and photoreceptor layers. Electron microscopy further confirmed that these cells might be apoptotic body ingesting phagocytes, whose function seemed to correlate with bcl-2 mRNA up-regulation. When histochemical studies were performed to determine the cellular identity of the phagocytes, the microglia were thought to be the one and only type of phagocytes involved in the KA-induced retinal apoptosis. In conclusion, we demonstrated that after KA injection, microglia were the only phagocytes to participate in clearing apoptotic debris from the inner retinal layers, and that their function might correlate with the change in expression of the bcl-2 gene family.

CM1, a possible novel activation molecule on human lymphocytes

CM1 (centrocyte/-blast marker 1) defined by a mAb developed against concanavalin-A activated PBMC, is expressed specifically on some tonsillar germinal center (GC) B cells. In single flow cytometric analysis, the bone marrow did not express these molecules nor did the PBMC or the thymocytes. The peripheral B lymphocytes showed more than 90% positive, while the peripheral T lymphocytes showed approximately 60% positive at 48 h after activation by PMA/ionomycin, respectively. A western blot analysis and an immunoprecipitation for CM1 showed a band at 70 kDa. Cross-linking of CM1 with anti-CM1 mAb induced apoptosis of the GC B cells (CD38(+)IgD(-)). Immunohistochemical staining revealed that the CM1 molecule is distributed over the entire area except the proximal dark zone of the tonsillar germinal centers. These results suggest that the CM1 molecule might be involved in differentiation of the germinal center B cells as one of the novel centrocyte markers.

Two opposing effects of non-steroidal anti-inflammatory drugs on the expression of the inducible cyclooxygenase. Mediation through different signaling pathways

The efficacy of non-steroidal anti-inflammatory drugs (NSAIDs) is considered to be a result of their inhibitory effect on cyclooxygenase (COX) activity. Here, we report that flufenamic acid shows two opposing effects on COX-2 expression; it induces COX-2 expression in the colon cancer cell line (HT-29) and macrophage cell line (RAW 264.7); conversely, it inhibits tumor necrosis factor alpha (TNFalpha)- or lipopolysaccharide (LPS)-induced COX-2 expression. This inhibition correlates with the suppression of TNFalpha- or LPS-induced NFkappaB activation by flufenamic acid. The inhibitor of extracellular signal-regulated protein kinase, p38, or NFkappaB does not affect the NSAID-induced COX-2 expression. These results suggest that the NSAID-induced COX-2 expression is not mediated through activation of NFkappaB and mitogen-activated protein kinases. An activator of peroxisome proliferator-activated receptor gamma, 15-deoxy-Delta(12,14)-prostaglandin J(2), also induces COX-2 expression and inhibits TNFalpha-induced NFkappaB activation and COX-2 expression. Flufenamic acid and 15-deoxy-Delta(12,14)-prostaglandin J(2) also inhibit LPS-induced expression of inducible form of nitric-oxide synthase and interleukin-1alpha in RAW 264.7 cells. Together, these results indicate that the NSAIDs inhibit mitogen-induced COX-2 expression while they induce COX-2 expression. Furthermore, the results suggest that the anti-inflammatory effects of flufenamic acid and some other NSAIDs are due to their inhibitory action on the mitogen-induced expression of COX-2 and downstream markers of inflammation in addition to their inhibitory effect on COX enzyme activity.

Common apolipoprotein A-IV variants are associated with differences in body mass index levels and percentage body fat

OBJECTIVE

To determine the relationship between two common apoA-IV variants (Thr347-->Ser; Gln360-->His), and body mass index (BMI) and percentage body fat.

DESIGN

Cross-sectional study.

SUBJECTS

Eight-hundred and forty-eight subjects screened for participation in ongoing clinical studies.

MEASUREMENTS

ApoA-IV genotype, body mass index, waist-to-hip ratio and percentage body fat by bioelectric impedance.

RESULTS

Participants had an average age of 41+/-12 y and an average BMI of 28.2+/-5.5 kg/m2. Individuals homozygous for the Ser347 allele had higher BMI (32.3+/-6.6 vs 28.6+/-5.3 kg/m2; P<0.01) and percentage body fat (36.9+/-7.8 vs 31.0+/-9.6%; P<0.05) compared with individuals homozygous for Thr347. In contrast, the presence of at least one copy of the His360 allele was associated with lower BMI (27.2+/-5.0 vs 28.4+/-5.6 kg/m2; P<0.05) and percentage body fat (28.6+/-8.2 vs 30.7+/-9.1%; P<0.05). The genotype effects persisted after normalization of the data for the potential confounding effects of gender, age and race. When grouped by BMI percentile, the frequency of the Ser347/Ser347 genotype increased while the frequency of the His360 allele decreased with increasing BMI.

CONCLUSIONS

These data suggest a role for apoA-IV in fat storage or mobilization and that genetic variations in the apoA-IV gene may play a role in the development of obesity.

Role of reconstituted basement membrane in human granulosa cell culture

The effects of Matrigel, a reconstituted basement membrane, on human granulosa cells were investigated. Cells were obtained from follicular aspirate in the course of oocyte retrieval for in vitro fertilization and were cultured on either a surface coated with Matrigel or uncoated plastic. Light and electron microscopy showed that granulosa cells cultured on Matrigel demonstrated three-dimensional aggregated cells with well differentiated morphology: numerous lipid droplets, microvilli, junctional complexes and lumen-like structures were seen. In contrast, cells cultured on plastic were flattened, poorly differentiated and showed apoptotic cells. Immunocytochemistry showed that the proportion of immunopositive cells for 3beta-hydroxysteroid dehydrogenase was increased in cultures on Matrigel. The results of the present study suggest that culture on Matrigel promotes the differentiation of human granulosa cells and provides a useful tool which may improve the efficiency of in vitro fertilization.

Primary carcinoma of the fallopian tube coexisting with benign cystic teratoma of the ovary

Primary carcinoma of the fallopian tube is a rare malignancy of the female genital tract and infrequently diagnosed before an operation. The majority of patients have extensive disease at the time of diagnosis. We have experienced incidentally a case of a carcinoma of the fallopian tube coexisting with a benign cystic teratoma of the ovary in a 25-year-old woman. We report this case with a brief review of literatures.

Localization of bcl-2 mRNA in the rabbit central nervous system

In this study, we demonstrated bcl-2 expression in the rabbit brain using in situ hybridization and compared the results with the studies done on the other animals. Although the bcl-2 expressions of the rabbit were generally similar to those of the other animals, some differences were also found; the cells in molecular and Purkinje cell layers of the cerebellum, which were bcl-2 negative in the others, showed intense bcl-2 positive signals, while the ependymal cells, arachnoid villi and granular layer, which were positive in the other animals, were not well stained with bcl-2 riboprobes in the rabbit brain. Our findings clearly showed the similarities and differences of rabbit bcl-2 mRNA as compared with the other species for the first time, and provided the basis of further study on the properties of bcl-2 in this species.

Bronchus-associated lymphoid tissue (BALT) lymphoma of the lung showing mosaic pattern of inhomogeneous attenuation on thin-section CT: a case report

The authors present a case of histologically proven bronchus-associated lymphoid tissue (BALT) lymphoma of the lung in a patient with primary Sjögren's syndrome that manifested on thin-section CT scan as a mosaic pattern of inhomogeneous attenuation due to mixed small airway and infiltrative abnormalities

Reconstituted basement membrane reduces proliferation and increases prolactin expression of GH3 cells

This study investigated the effects of reconstituted basement membrane Matrigel on the proliferation and prolactin expression of GH3 cells in culture for 6 days. When cells were cultured on Matrigel, the initial attachment was increased but the cell number was not changed with time whereas rapid increase in cell number was observed in cultures on plastic. Bromodeoxyuridine (BrdU)-labeling showed that BrdU incorporation ratio of GH3 cells cultured on Matrigel was about one half of that observed with cells cultured on plastic (9.7+/-0.7% vs. 18.7+/-1.2%). Immunocytochemistry revealed that the ratio of the prolactin-immunoreactive GH3 cells was about 3.6 times (58.4+/-2.9% on Matrigel vs. 16.2+/-1.4% on plastic), which was compatible with the results of Western blot analysis. In situ hybridization demonstrated that prolactin mRNA-positive cells were identified more frequently when cells were cultured on Matrigel compared to cultures on plastic. These findings indicate that Matrigel is a proper culture substrate for the long-term culture of GH3 pituitary cells due to the inhibition of overgrowth and promotion of prolactin expression.

Are substance P neurons of the paraventricular nucleus related to the osmotic regulation in the Mongolian gerbil?

In recent years, the gerbil has been used as an experimental animal for study osmotic regulation, because of its inherent high degree of water re-uptake in kidney. Many evidences to explain this characteristic accumulated on the kidney level, it do not, however, manifest what concerns on hypothalmo-hypophyseal level. In this study, we have focused on the difference between the colchicine treated gerbil and rat in distributions of substance P (SP), which is known to have antidiuretic property. Unlike rat, in which a few SP+ neuron is present, SP+ neurons were abundantly observed in the paraventricular nucleus (PVN) of the gerbil. Furthermore SP+ cells in PVN were manifested in dehydrated gerbils, in spite of non-colchicine treatment. Therefore, we suggest that the abundant SP+ neurons in PVN may be a clue to address the neuroendocrinal mechanism concerning the high degree of osmotic regulation in this animal.

Engagement of CD99 induces apoptosis through a calcineurin-independent pathway in Ewing's sarcoma cells

Programmed cell death (PCD) is a prominent feature of the development of the immune and nervous systems. In both systems, widespread PCD occurs in primitive progenitor cells during development. In this study, we demonstrated that Ewing's sarcoma (ES) cells, undifferentiated neural precursors, underwent apoptosis upon engagement of CD99 with anti-CD99 monoclonal antibody. Apoptosis via CD99 occurred only in the undifferentiated state of ES cells, but not in differentiated ES cells. CD99-induced apoptosis in ES cells appeared to require de novo synthesis of RNA and protein as well as caspase activation. Cyclosporin A, known to be a potent inhibitor of both calcineurin activation and mitochondrial permeability transition pore opening, inhibited CD99-mediated apoptosis, whereas FK-506, a specific calcineurin inhibitor, did not, indicating the induction of CD99-mediated apoptosis through a calcineurin-independent pathway. Furthermore, the dying cells displayed the reduction of mitochondrial transmembrane potential (delta psi m). These results suggest that CD99 engagement induce CsA-inhibitable mitochondrial permeability transition pore opening, followed by a reduction of delta psi m and caspase activation, thereby leading to apoptosis. Based on these results, we suggest the possible involvement of CD99 in the apoptotic processes that occur during nervous system development and also its application in immunotherapeutic trials for ES cases.

Localization of transferrin binding protein in relation to iron, ferritin, and transferrin receptors in the chicken cerebellum

We have demonstrated that transferrin binding protein (TfBP), ferritin, and iron, are specifically localized in Bergmann glia, while the transferrin receptor is confined to Purkinje cells in the chicken cerebellum. The results of this study suggest that Bergmann glia have previously undescribed functions related to iron regulation such as sequestration of iron and the maintenance of iron homeostasis in the cerebellum.

Epidermolysis bullosa acquisita in childhood--a case mimicking chronic bullous dermatosis of childhood

Epidermolysis bullosa acquisita (EBA) is rarely reported in childhood, but we now describe a 6-year-old Korean girl with the condition. She presented with multiple tense bullae annularly distributed on the perioral, periorbital and genital areas, and was successfully treated with dapsone. The clinical and histological features were similar to those of chronic bullous dermatosis of childhood. We review seven previously reported childhood EBA cases and contrast their features with those of adult EBA. We suggest that some childhood EBA is different from the adult form and shares features with chronic bullous dermatosis of childhood.

Does vegetable oil attenuate the beneficial effects of fish oil in reducing risk factors for cardiovascular disease?

Contradictory reports on the protective effect of fish consumption on cardiovascular disease (CVD) risk could be due to variations in the intake of n-3 and n-6 polyunsaturated fatty acids (PUFAs). Metabolic competition between n-3 and n-6 PUFAs suggests that n-6 PUFAs in vegetable oils could attenuate the efficacy of n-3 PUFAs in fish oil to favorably alter endpoints relevant to CVD risk. We determined the effects of varying dietary amounts of fish oil on lipid and thrombotic endpoints relevant to risk factors for CVD and whether these effects were attenuated by vegetable oils. Two randomized, double-blind, placebo-controlled, parallel studies were conducted in human subjects fed varying amounts of n-3 and n-6 PUFAs; n-3 PUFA intake was varied by using fish or placebo oil capsules, and n-6 PUFA intake was modified by incorporating varying amounts of safflower oil into the diet. Endpoints included changes in membrane fatty acid composition, blood lipids, and thrombotic profile. The results indicated that absolute amounts of fish oil, and not the relative amounts of fish and vegetable oil (ratios of n-3 to n-6 PUFAs), determined the magnitude of the reduction of arachidonic acid and increase in eicosapentaenoic acid in phospholipids of plasma and platelets. The suppression of plasma triacylglycerols by fish oil was not affected by varying amounts of dietary n-6 PUFAs. Fibrinogen concentrations decreased with 15 g but not with 9 g fish oil/d fed at the same ratio of n-3 to n-6 PUFAs. The efficacy of fish oil in favorably modifying certain risk factors for CVD was not attenuated by vegetable oil.

Distribution of transferrin binding protein immunoreactivity in the chicken central and peripheral nervous systems

Transferrin binding protein (TfBP) is a glycoprotein originally purified from chicken oviduct that exhibits transferrin binding activity. Recent work has shown that TfBP is a post-translationally modified form of the heat shock protein (HSP108), the avian homologue of a glucose regulated protein, GRP94. The function of this protein, however, has not yet been clearly defined. Antiserum to TfBP was found to selectively stain oligodendrocytes of the avian brain. In this study, we further describe these oligodendrocytes and other cell types positive to anti-TfBP in the chick nervous system. In accordance with previous studies, the most prominent cell type that labels with antiserum to TfBP is the oligodendrocyte. At the electron microscopic level, the immunoreactive product is confined to the perinuclear cytoplasm and fine processes of the oligodendrocytes, whereas myelin and axoplasm are devoid of staining. The immunoreactive product is found both in the cytoplasmic matrix and bound to the endoplasmic reticulum and plasma membrane, suggesting that TfBP may have properties of both a soluble and an integral membrane protein. There is great variability in the number of TfBP-oligodendrocytes in different areas of the central nervous system (CNS); large numbers of cells are associated with the white matter regions and are found in the myelinated tracts, whereas few cells are present in the gray matter regions. In the retina, TfBP is localized specifically in the cells, that are morphologically oligodendrocytic and is present in the optic nerve fiber layer and the ganglion cell layer. Obvious staining is also seen in the Bergmann glial cells of the cerebellum and in the Schwann cells of the sciatic nerve. Furthermore, the choroid plexus cells similarly exhibit a strong reaction. The association of TfBP in these specific cell types responsible for myelination and sequestering iron and transferrin implies that TfBP may be involved in myelination and iron metabolism of the chick nervous system, perhaps through a role in transferrin concentration in these cells. A putative role of TfBP, as HSP108, is considered.

Effects of essential fatty acid deficiency on prostaglandin E2 production and cell-mediated immunity in a mouse model of leprosy

Results from animal and in vitro studies suggest that essential fatty acid (EFA) deficiency enhances cell-mediated immunity by reducing production of prostaglandins with immunosuppressive actions. However, direct experimental evidence that EFA deficiency enhances T-lymphocyte function in vivo has not been obtained. In this study, athymic (nu/nu) mice were infected in the footpads with Mycobacterium leprae and fed a linoleic acid-free diet. These mice, and infected nu/nu mice on control diets, were given an adoptive transfer of M. leprae-primed, T-cell-enriched lymphocytes. After 2 weeks, M. leprae bacilli were harvested from the recipient mice and bacterial viability was determined by the BACTEC system. M. leprae recovered from recipient mice fed control diets displayed little reduction in metabolic activity. In contrast, M. leprae from recipient mice fed the EFA-deficient (EFAD) diet exhibited markedly reduced viability. In vitro, donor cells from M. leprae-primed mice secreted elevated levels of gamma interferon upon exposure to the bacilli. These cells also exhibited an enhanced proliferative response, which was reduced by exogenous prostaglandin E2 (PGE2). In addition, M. leprae-infected granuloma macrophages (Mphi) from EFAD recipient nu/nu mice secreted significantly less PGE2 than granuloma Mphi from mice on control diets. These data suggest that enhanced levels of Mphi-generated PGE2, induced by M. leprae or its constituents, could act as an endogenous negative modulator of the immune response occurring in the microenvironment of the lepromatous granuloma.

Colloid cyst of the third ventricle

BACKGROUND

Colloid cyst of the third ventricle has rarely been reported in the ophthalmic literature. The incidence is about one per 1000 in asymptomatic patients and accounts for 0.55 to 2 percent of all intracranial tumors. Although it is an uncommon benign tumor, nearly half of symptomatic patients present with papilledema and hydrocephalus. Consideration of this intracranial tumor should be included in the differential diagnosis of papilledema and apparent unilateral disc edema.

METHODS

A patient with highly asymmetrical papilledema and vague visual symptomatology involving the right eye was studied. Computer axial tomography (CT) without contrast enhancement revealed a colloid cyst of the third ventricle. Typical symptoms of the condition include headaches, nausea, vomiting, visual obscuration, transient diplopia and weakness of the lower extremities, which are due to acute hydrocephalus caused by increased intracranial pressure from cystic obstruction of the foramen of Monro. Intermittency of symptoms is characteristic of this lesion.

RESULTS

The patient underwent frontal craniotomy with total tumor excision and reopening of the cerebrospinal fluid pathway.

CONCLUSIONS

Colloid cyst of the third ventricle discovered incidentally on CT in asymptomatic patients with no evidence of hydrocephalus can be monitored periodically. If symptomatic, neurosurgery is usually indicated since prolonged increased intracranial pressure can lead to mental and physical deterioration as well as sudden death.

Incorporation of different types of n-3 fatty acids into tissue lipids of poultry

The objective of the present study was to compare the incorporation of different types of n-3 polyunsaturated fatty acids into thigh muscle lipids of poultry. Nine groups of broiler chicks were fed diets supplemented with three levels (1.0, 2.5, and 5.0%) of either corn, linseed, or menhaden oil. Birds supplemented with linseed oil, rich in linolenic acid (C18:3n-3), had significantly higher levels of n-3 fatty acids and higher n-3:n-6 ratios than those supplemented with the same level of menhaden oil, primarily due to an accumulation of C18:3n-3. Levels of eicosapentaenoic acid (C20:5n-3) were increased (P less than .05), compared with the controls fed the same level of corn oil, in the groups fed the two higher levels of linseed oil, and in all the groups fed menhaden oil. Linolenic acid is less susceptible to auto-oxidation, and is less likely to impart an off-flavor to the muscle. Thus, if it is desirable to increase the n-3:n-6 ratio in poultry, seed meals or oils with a high content of C18:3n-3 could be used in poultry feeds.

Effects of diets high in saturated fatty acids, canola oil, or safflower oil on platelet function, thromboxane B2 formation, and fatty acid composition of platelet phospholipids

Platelet function and fatty acid composition were investigated in 30 healthy male subjects who ate a controlled-saturated-fatty-acid (baseline) diet for 3 wk and then consumed either safflower oil or canola oil as a major fat source for 8 wk. Fatty acid composition of platelet phospholipids reflected changes in dietary fatty acid composition. Compared with baseline a 35% decrease (P less than 0.05) in arachidonic acid was observed in platelet phospholipids of the canola-oil diet group while long chain n-3 fatty acids rose 7-26% (P greater than 0.05). Compared with baseline both unsaturated-fatty-acid diets reduced platelet aggregation at 3 wk of oil-based diet feeding (P less than 0.01) whereas only canola oil influenced platelet function (lowered ATP secretion) at 8 wk (P less than 0.01). No significant difference was observed in thromboxane B2 concentrations between oil-treatment groups at 8 wk. Both oil-based diets had short-term beneficial effects on platelet function but the effect of canola oil persisted longer.

Dietary (n-3) fatty acids alter fatty acid composition and prostaglandin synthesis in rat testis

The objective of this study was to determine the efficacy of linolenic acid [18:3(n-3)], compared with the long-chain (n-3) fatty acids in fish oil, in suppressing arachidonic acid [20:4(n-6)] metabolism in rat testis. Six groups of rats were fed three levels of 18:3(n-3) or fish oil, and the fatty acid composition of testis parenchyma lipids and prostaglandin (PG) I2 synthesis by tunica were determined after 12 wk. Levels of docosapentaenoic acid [22:5(n-6)], the major 22-carbon fatty acid in rat testis lipids, were significantly depressed compared with the control by both linolenic acid and fish oil; however, testis weights were not affected significantly. Arachidonic acid levels also were depressed significantly in testis lipids by dietary (n-3) fatty acids, but the decreases were not as pronounced as those observed in other tissues. The synthesis of PGI2 was significantly reduced compared with the control by (n-3) fatty acid feeding, but there were no differences among the experimental groups. Both 18:3(n-3) and the longer-chain (n-3) fatty acids from fish oil reduce levels of 20:4(n-6) and 22:5(n-6) in testis lipids and the capacity of the tunica to synthesize PGI2, but these fatty acids seem to cause no defect in testicular development as indicated by weight.

Lack of dose response by dietary n-3 fatty acids at a constant ratio of n-3 to n-6 fatty acids in suppressing eicosanoid biosynthesis from arachidonic acid

This study evaluated whether it is the ratio of n-3 to n-6 fatty acids or the absolute amount of n-3 fatty acids in diets that determines the degree of inhibition of eicosanoid biosynthesis from arachidonic acid (AA). Rats were fed diets containing different doses of linolenic acid or menhaden oil for 3 mo. Constant ratios of n-3 to n-6 fatty acids were maintained by concomitant increases in safflower oil as the n-6 fatty acid source. Results showed that AA concentrations in liver, platelet, and lung phospholipids and concentrations of eicosanoids synthesized in tissues were significantly (P less than 0.05) suppressed both by linolenic acid and menhaden oil; however, there was a lack of a dose response within groups fed different amounts of the same dietary fat. These results indicate that the ratio of n-3 to n-6 fatty acids in the diets, rather than the absolute amount of n-3 fatty acids, is the determining factor in inhibiting eicosanoid biosynthesis from AA.

Dietary linolenic acid and longer-chain n-3 fatty acids: comparison of effects on arachidonic acid metabolism in rats

Rats were fed graded amounts of purified 18:3n-3 or fish oil concentrate in the presence of a constant amount of 18:2n-6 to evaluate the ability of 18:3n-3 compared with longer-chain n-3 fatty acids to inhibit 20:4n-6 metabolism in platelets and lungs. Dietary 18:3n-3 at a ratio of 0.28 (n-3 to n-6 fatty acids) suppressed levels of 20:4n-6 in lung and plasma phospholipids and the capacity of the tissues to synthesize cyclooxygenase-derived products in a dose-dependent fashion. At similar ratios of n-3 to n-6 dietary fatty acids, longer-chain n-3 fatty acids, which are abundant in fish oil, appear to be more effective than 18:3n-3 in suppressing 20:4n-6 levels and the capacity of the tissues to synthesize cyclooxygenase-derived products. Much greater amounts of 12-hydroxyeicosapentaenoic acid (12-HEPE) and 5-HEPE than of 12-hydroxyeicosatetraenoic acid (12-HETE) and 5-HETE appeared to be formed in tissues of the group receiving the highest amount of fish oil. These results suggest that ingestion of fish oil leads to increased formation of lipoxygenase-derived products of longer-chain n-3 fatty acids.

Transitional changes in arachidonic acid metabolism by bovine embryos at different developmental stages

In order to determine the profile of arachidonic acid (AA) metabolites synthesized by bovine embryos during early developmental stages, embryos collected from superovulated beef cattle (days 6 through 17) were incubated with AA and its metabolites were analyzed by high performance liquid chromatography and radioimmunoassay (RIA). Embryos harvested and cultured before day 12 of the estrous cycle metabolized AA primarily to prostaglandin E2 (PGE2), whereas, those harvested on day 13 of the cycle metabolized AA to both PGE2 and PGF2 alpha. Furthermore, embryos collected after day 15 of the cycle metabolized AA to PGI2 in addition to PGE2 and PGF2 alpha. In view of the luteotropic properties that have been attributed to PGE2 and the vasodilatory effect of PGI2, this transitional change in prostaglandin synthesis during early stages of embryonic development may be a part of the mechanism by which the embryo exerts a luteotropic effect leading to maternal recognition of pregnancy and by which the conceptus begins preparing for subsequent implantation.

Effects of chronic ethanol ingestion on arachidonic acid metabolism in rat tissues and in vitro effect of ethanol on cAMP in platelets

Effects of chronic ethanol ingestion (3 weeks) on the capacity of peritoneal macrophages, lung and heart tissues, to metabolize endogenous arachidonic acid (AA) in rats, and the in vitro effect of ethanol on 3'-5' cyclic adenosine monophosphate (cAMP) levels in rat platelets were studied. Peritoneal resident macrophages were stimulated by calcium ionophore (A23187) and levels of 5-hydroxyeicosatetraenoic acid (5-HETE), leukotriene B4 (LTB4) and PGE2 were measured by radioimmunoassay. There were no differences in levels of the eicosanoids synthesized by macrophages between the ethanol treated and the control group. There were also no differences found in levels of the eicosanoids synthesized by heart or lung homogenate between the two groups. These results suggest that chronic ethanol ingestion does not alter the capacity to synthesize the eicosanoids from the endogenous precursor in tissues studied here. Preincubation of ethanol with platelet rich plasma resulted in a dose dependent increase in cAMP levels. The well documented inhibitory effects of ethanol in vitro on aggregation and AA metabolism in platelets may be due to the enhanced cAMP levels.

Effects of dietary linolenate on the fatty acid composition of brain lipids in rats

Weanling male rats were fed hydrogenated coconut oil to induce essential fatty acid (EFA) deficiency. After 15 weeks, the rats were divided into six groups. Five groups were fed graded amounts of purified linolenate (18:3 omega 3) with a constant amount of linoleate (18:2 omega 6) for six weeks. Fatty acid composition was determined in brain lipids. Increasing dietary 18:3 omega 3 resulted in a decrease in arachidonic acid (20:4 omega 6), docosatetraenoic acid (22:4 omega 6) and docosapentaenoic acid (22:5 omega 6), whereas 18:2 omega 6 and eicosatrienoic acid (20:3 omega 6) were increased both in total lipids and phospholipids. These results suggest that dietary 18:3 omega 3 exerts its inhibitory effect mainly on the desaturation of 20:3 omega 6 to 20:4 omega 6 in brain lipids. Linolenate was undetectable in brain lipids from any dietary treatments. The levels of eicosapentaenoic acid (20:5 omega 3) in groups receiving dietary 18:3 omega 3 were not different from that of the group receiving no 18:3 omega 3. These results indicate that, in the brain, 18:3 omega 3 is rapidly converted mainly to 22:6 omega 3 without being accumulated and imply that dietary 18:3 omega 3 can modulate the level of precursor of diene prostaglandins (PG) but not that of triene PG in the rat brain.

Fatty acid composition of the testes of zinc-deficient rats: the effect of docosapentaenoic acid supplementation

To determine if low levels of docosapentaenoic acid (22:5 omega 6), observed in the testis lipids of zinc-deficient rats, are related to some of the symptoms of zinc deficiency in rat testes, four groups of rats were fed egg white- and corn oil (CO)-based semipurified diets. One group was fed a zinc-deficient diet (ZDCO) and a control group was pair-fed a zinc-supplemented diet (PFCO). Two additional groups were treated in an identical fashion, but their diets were supplemented with 1% testis lipid (TL) containing 10-12% 22:5 omega 6 (ZDTL and PFTL). Testes weights and sperm counts were slightly higher in ZDTL compared to ZDCO, but these trends were not statistically significant. Testis zinc concentrations were significantly higher in both TL groups compared to the corresponding CO group. Dietary 22:5 omega 6 appeared to be accumulated in liver lipids; however, there was no difference between TL and CO groups in 22:5 omega 6 level in testes phospholipids or testes total lipids. These results indicate that 22:5 omega 6 concentration and spermatogenesis in the testes of zinc-deficient rats do not appear to be affected by the dietary supplementation of 22:5 omega 6 at the level used in this study.