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This review explores the significant progress and applications of artificial intelligence (AI) in obstetrics and gynecological MRI, charting its development from foundational algorithmic techniques to deep learning strategies and advanced radiomics. This review features research published over the last few years that has used AI with MRI to identify specific conditions such as uterine leiomyosarcoma, endometrial cancer, cervical cancer, ovarian tumors, and placenta accreta. In addition, it covers studies on the application of AI for segmentation and quality improvement in obstetrics and gynecology MRI. The review also outlines the existing challenges and envisions future directions for AI research in this domain. The growing accessibility of extensive datasets across various institutions and the application of multiparametric MRI are significantly enhancing the accuracy and adaptability of AI. This progress has the potential to enable more accurate and efficient diagnosis, offering opportunities for personalized medicine in the field of obstetrics and gynecology.

Mechanical stiffness is closely related to cell adhesion and rounding in some cells. In leukocytes, dephosphorylation of ezrin/radixin/moesin (ERM) proteins is linked to cell adhesion events. To elucidate the relationship between surface stiffness, cell adhesion, and ERM dephosphorylation in leukocytes, we examined the relationship in the myelogenous leukemia line, KG-1, by treatment with modulation drugs. KG-1 cells have ring-shaped cortical actin with microvilli as the only F-actin cytoskeleton, and the actin structure constructs the mechanical stiffness of the cells. Phorbol 12-myristate 13-acetate and staurosporine, which induced cell adhesion to fibronectin surface and ERM dephosphorylation, caused a decrease in surface stiffness in KG-1 cells. Calyculin A, which inhibited ERM dephosphorylation and had no effect on cell adhesion, did not affect surface stiffness. To clarify whether decreasing cell surface stiffness and inducing cell adhesion are equivalent, we examined KG-1 cell adhesion by treatment with actin-attenuated cell softening reagents. Cytochalasin D clearly diminished cell adhesion, and high concentrations of Y27632 slightly induced cell adhesion. Only Y27632 slightly decreased ERM phosphorylation in KG-1 cells. Thus, decreasing cell surface stiffness and inducing cell adhesion are not equivalent, but these phenomena are coordinately regulated by ERM dephosphorylation in KG-1 cells., (© 2021. Japan Human Cell Society.)

Background: We previously demonstrated that lubrication of an endotracheal tube (ETT) cuff with K-Y™ jelly strongly and significantly inhibited the increase in cuff pressure during nitrous oxide (N 2 O) exposure in vitro. However, in our previous study, we identified critical differences between some influential factors, such as the amount of lubricant retained on the cuff, and studied temperature differences between laboratory and clinical conditions. Therefore, it remained unclear whether this effect holds true in clinical settings., Methods: We first sought to study how changes in the amount of K-Y™ jelly and temperature influence the inhibitory effects of the lubricant on the increase in N 2 O-induced cuff pressure in vitro. Furthermore, we aimed to determine whether the application of K-Y™ jelly inhibits the increase in ETT cuff pressure during general anesthesia using N 2 O in adult patients., Results: In the laboratory studies, we found that K-Y™ jelly inhibited the cuff pressure increase dose-dependently when the dose of K-Y™ jelly was varied (P = 0.02), and that such an inhibitory effect decreased with an increase in the studied temperature (P = 0.019). In the clinical study, lubrication with K-Y™ jelly slightly, but significantly, delayed the increase in ETT cuff pressure during general anesthesia with N 2 O (P = 0.029). However, the inhibitory effect in the clinical settings was smaller than that in vitro., Conclusions: Lubrication of the ETT cuff with K-Y™ jelly may delay the increase in cuff pressure during general anaesthesia with N 2 O. However, the clinical significance of this effect may be limited., Trial Registration: UMIN Clinical Trials Registry: UMIN000031377 on March 1, 2019.

Background: The descending antinociceptive system (DAS) is thought to play crucial roles in the antinociceptive effect of spinal cord stimulation (SCS), especially through its serotonergic pathway. The nucleus raphe magnus (NRM) in the rostral ventromedial medulla is a major source of serotonin [5-hydroxytryptamine (5-HT)] to the DAS, but the role of the dorsal raphe nucleus (DRN) in the ventral periaqueductal gray matter is still unclear. Moreover, the influence of the noradrenergic pathway is largely unknown. In this study, we evaluated the involvement of these serotonergic and noradrenergic pathways in SCS-induced antinociception by behavioral analysis of spinal nerve-ligated (SNL) rats. We also investigated immunohistochemical changes in the DRN and locus coeruleus (LC), regarded as the adrenergic center of the DAS, and expression changes of synthetic enzymes of 5-HT [tryptophan hydroxylase (TPH)] and norepinephrine [dopamine β-hydroxylase (DβH)] in the spinal dorsal horn., Results: Intrathecally administered methysergide, a 5-HT1- and 5-HT2-receptor antagonist, and idazoxan, an α2-adrenergic receptor antagonist, equally abolished the antinociceptive effect of SCS. The numbers of TPH-positive serotonergic and phosphorylated cyclic AMP response element binding protein (pCREB)-positive neurons and percentage of pCREB-positive serotonergic neurons in the DRN significantly increased after 3-h SCS. Further, the ipsilateral-to-contralateral immunoreactivity ratio of DβH increased in the LC of SNL rats and reached the level seen in naïve rats, even though the number of pCREB-positive neurons in the LC was unchanged by SNL and SCS. Moreover, 3-h SCS did not increase the expression levels of TPH and DβH in the spinal dorsal horn., Conclusions: The serotonergic and noradrenergic pathways of the DAS are involved in the antinociceptive effect of SCS, but activation of the DRN might primarily be responsible for this effect, and the LC may have a smaller contribution. SCS does not potentiate the synthetic enzymes of 5HT and norepinephrine in the neuropathic spinal cord.

Background/aim: To investigate portal vein stenosis after living-donor liver transplantation by liver scintigraphy., Methodology: A 63-year-old woman with hepatic cirrhosis due to autoimmune hepatitis underwent living-donor liver transplantation using a graft donated by her daughter. Technetium-99m-diethylenetriaminepentaacetic acid-galactosyl human serum albumin (Tc-99m-GSA) scintigraphy was used to determine the maximum rate of Tc-99m-GSA removal (GSA-Rmax) by hepatocytes, as a parameter of hepatic functional reserve., Results: Conventional liver function parameters on laboratory tests and graft volume on computed tomography (CT) were almost unchanged at postoperative month (POM) 12. GSA-Rmax was 0.11 mg/min before surgery and increased 5-fold to approximately 0.5 mg/min at POM 1 and 3, followed by a decrease to 0.25 mg/min at POM 6 and 12. Enhanced CT did not detect blood flow in the intra- or extrahepatic portions of the portal vein at POM 12. The portal vein stenosis was dilated with a balloon catheter, followed by deployment of a self-expanding stent across the stenotic segment via the transileocolic vein. GSA-Rmax recovered to 0.5 mg/min at POM 15, and subsequently remained high., Conclusions: Decreased GSA-Rmax at POM 6 indicated that the portal vein stenosis was affecting graft function. Tc-99m-GSA liver scintigraphy may be a useful noninvasive method for evaluation of graft functional reserve.

The mechanisms underlying paclitaxel-induced peripheral neuropathy remain unknown. Nerve growth factor (NGF) is a representative neurotrophic factor that maintains neuronal function, promotes survival, and mediates neuropathic pain. We investigated expression levels of NGF and its receptors in the dorsal root ganglia (DRG) and spinal dorsal horn (DH) following paclitaxel treatment. Intraperitoneal (I.P.) administration of paclitaxel induced significant mechanical hypersensitivity and cold allodynia in rats, significantly increased the expression of NGF and its receptor tyrosine kinase receptor A (trkA) in the DRG, and increased NGF expression in the DH. In contrast, paclitaxel treatment did not alter the mRNA levels of NGF or its receptors in the DRG, DH, sciatic nerve, or hindpaw skin. Moreover, expression of NEDD4-2, a negative regulator of trkA, was significantly increased in the DRG of paclitaxel-treated rats. Intrathecal (I.T.) administration of the tyrosine kinase receptor inhibitor k252a significantly alleviated mechanical hypersensitivity in paclitaxel-treated rats. Our results suggest that NGF-trkA signaling is involved in mechanical allodynia in paclitaxel-induced neuropathy., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Background: We previously reported that preoperative chemolipiodolization of the whole liver is effective for reducing the incidence of postoperative recurrence and prolonging survival in patients with resectable hepatocellular carcinoma (HCC). The present randomized controlled trial was performed to evaluate the influence of preoperative transcatheter arterial chemoembolization (TACE) on survival after the resection of HCC., Methods: Operative results and long-term outcome were prospectively compared among 42 patients who received only selective TACE targeting the tumor (selective group), 39 patients who received TACE targeting the tumor plus chemolipiodolization of the whole liver (whole-liver group), and 43 patients without preoperative TACE or chemolipiodolization (control group)., Results: There were no serious side effects of TACE or chemolipiodolization and the operative outcomes did not differ among the three groups. Even though preoperative TACE induced complete tumor necrosis, there were no significant differences in the pattern of intrahepatic recurrence or the time until recurrence among the three groups. There were also no significant differences in disease-free survival or overall survival among the three groups, even among patients with larger tumor size., Conclusion: These results indicate that preoperative selective TACE and whole-liver chemolipiodolization plus TACE do not reduce the incidence of postoperative recurrence or prolong survival in patients with resectable HCC.

A 15-year-old boy with subarachnoid hemorrhage was planned for emergency cerebral aneurysm clipping under general anesthesia. He had different blood pressure between the upper limbs and we found coarctation of the aorta at left subclavian artery bifurcation in the preoperative angiography. To prevent re-rupture of cerebral aneurysm and ischemia of abdominal organs, we monitored arterial blood pressure in bilateral radial arteries and non-invasive blood pressure in the left thigh, and his blood pressure was maintained within 120-150 mmHg of systolic pressure in the right radial artery and 50-70 mmHg of mean arterial pressure in the left radial artery and the left thigh during general anesthesia. The preoperative period elapsed uneventfully and the patient was planned for repair of coarctation of the aorta after discharge.

The percentage of MUFA to total fatty acids of beef differs among intermuscular, intramuscular, and subcutaneous fat even within an individual cow. Our objective was to investigate the variation of the percentage of MUFA by geometric and sectional change of marbling flecks in rib eye. Longissimus muscles of 8 Japanese Black steers from a common sire and a common maternal grand sire were used. Three slices (1 from rib roast and 2 from sirloin) from each animal were selected for analysis. Five marbling flecks from each slice were randomly taken to obtain the percentage of MUFA using gas chromatography. High-quality digital images of all slices were taken with a mirror-type camera. The area and location of each marbling fleck were calculated by image analysis. The marbling flecks were categorized by area [small <0.4 cm(2), medium 0.4 to 2.0 cm(2), large >2.0 cm(2)], by location (dorsal and ventral), and by slice section through the LM (front, middle, and back). The effects of classification according to the area, location, and slice section were statistically significant (P < 0.05) for the percentage of MUFA. Least squares means of the percentage of MUFA for marbling flecks of sizes small, medium, and large were 56.8, 58.4, and 60.2%, respectively, indicating that larger marbling flecks had greater MUFA (P < 0.05). Those of dorsal, ventral, front, middle, and back were 59.1, 57.8, 55.4, 59.9, and 60.1%, respectively. The percentages of MUFA of the marbling flecks located in the dorsal part were greater than those in the ventral part (P < 0.05). The percentages of MUFA from middle and back were greater than those from front (P < 0.01). We suggest that the area, location, and slice section of marbling would be the determining factors for the percentage of MUFA of marbling.

Aim: To investigate the total cytochrome P450 (CYP) content, microsomal mixed-function oxidase (MFO) activity, and expression of mRNAs for various CYP isozymes in a simple rat model of reversible obstructive jaundice., Methods: Obstructive jaundice was created in male rats by causing bile duct obstruction with polyester tape. In another group of rats, bile duct obstruction was followed by internal biliary drainage after releasing the tape. The expression of various CYP isozyme mRNAs was semi-quantitatively assessed by competitive RT-PCR., Results: The total CYP content and microsomal MFO activity showed a significant decrease after biliary obstruction, but returned to respective control levels after biliary drainage. A marked reduction in the expression of CYP1A2, 2B1/2, 2C11, 2E1, 3A1, and 3A2 mRNA was detected during biliary obstruction, while expression increased significantly toward the control level after biliary drainage. Although expression of CYP4A1 mRNA showed no reduction during biliary obstruction, it still increased significantly after biliary drainage., Conclusion: These results suggest that not only obstructive jaundice, but also the subsequent internal biliary drainage may affect regulatory medications of the synthesis of individual CYP isozymes differently.

Cisplatin is commonly used as a chemotherapeutic agent for hepatocellular carcinoma (HCC). However, it cannot satisfactorily improve the survival rate for patients with advanced HCC due to intrinsic or acquired drug resistance caused by multidrug resistance-associated proteins (MRPs). To clarify whether or not glycyrrhizin and lamivudine have modulator effects on HCC treated with cisplatin, we established a cisplatin-resistant Huh7 HCC cell line and analyzed the mRNA expression of MRPs in the resistant cells. The resistant cells showed 14.1-fold higher resistance to cisplatin, and they expressed higher levels of MRP2 (6.29-fold), MRP3 (3.2-fold), MRP4 (11.3-fold) and MRP5 (3.39-fold) mRNAs than the wild-type cells by using real-time PCR. However, MRP1, MDR1 and GST-pi mRNA were not induced. Compared with the treatment of the resistant cells with cisplatin only, co-treatment with cisplatin and glycyrrhizin or lamivudine significantly decreased the cell viability to 76.8% and 79.5%, respectively. Co-treatment with cisplatin and both glycyrrhizin and lamivudine further decreased the cell viability to 65.1%. Intracellular concentration of cisplatin in the resistant cells decreased to 36.4% of that of the wild-type cells while it increased to 47.7% or 48.4% when glycyrrhizin or lamivudine were added separately, or 60% when they were added together. Our findings indicate the following: i) high expression of MRP2, MRP3, MRP4 and MRP5 decreases cisplatin accumulation in cisplatin-resistant HCC cells and contributes to cisplatin resistance; ii) glycyrrhizin and/or lamivudine accumulate cisplatin in resistant cells by inhibiting the cisplatin efflux from the cells; and iii) glycyrrhizin and lamivudine both act as modulators and have the effect of reversing cisplatin resistance, and co-treatment with glycyrrhizin and lamivudine enhances modulator activity in reversing the cisplatin resistance.

We report a case of a 35-year-old woman with myotonic dystrophy and severe obesity of BMI 43.3 who showed persistent apnea at emergence after ovarian resection. The patient received an iv induction with minimum dose of propofol and vecuronium 3 mg. Anesthesia was maintained with propofol, 50% nitrous oxide and 50% oxygen mixture and epidural anesthesia. Additional vecuronium 0.5 mg was administered twice. Surgery was performed uneventfully within 130 minutes and iv propofol was discontinued. The patient awoke promptly after termination of nitrous oxide but no spontaneous breathing appeared with end-tidal CO2 of 60 mmHg. Because she could obey the order to breathe, the endotracheal tube was removed 40 minutes after discontinuation of propofol. Spontaneous breathing at the rate of 17 x min(-1) started soon after extubation. We assume that this apnea was caused by breath holding. Whether this breath holding is specific to myotonic dystrophy or not, anesthesia for patients with this disease requires careful attention for perioperative respiratory management.

Bezafibrate has been empirically used for the treatment of primary biliary cirrhosis. Although its clinical efficacy has been demonstrated, the therapeutic mechanism of action of this drug remains unclear. We suggested that multi-drug resistance (MDR) 3 plays an important role as a mediator of bezafibrate. We adopted a human hepatoma cell line to elucidate the up-regulating effect of bezafibrate. To analyze the effects on mRNA, the dose effect was assessed by slot-blot study, the time course by real time PCR, and the subcellular location was determined by in situ hybridization. The results revealed that MDR3 mRNA reached a peak level 12h after the administration of bezafibrate, and dose dependency was observed. We also investigated the interaction of bile acid and bezafibrate. A low dose of chenodeoxycholic acid could become a co-effecter of bezafibrate. In the protein analysis, a precursor protein was induced by bezafibrate. Even in the cell line endogenously expressing MDR3, the expression of the protein was found to be modulated. We identified MDR3 mRNA in the livers of PBC patients using a sensitive in situ hybridization study. The present findings indicate that PBC patients can respond to bezafibrate, and therefore receive clinical benefits from this medication.

Mammalian ferrochelatase, the terminal enzyme of the heme biosynthetic pathway, catalyzes the insertion of a ferrous ion into protoporphyrin and contains a labile [2Fe-2S] cluster center at the C-terminus. To clarify the roles of the iron-sulfur cluster in the expression of mammalian ferrochelatase, enzyme activity in human erythroleukemia K562 cells under iron-depleted conditions was examined. Treatment of cells with an iron chelator, desferrioxamine, resulted in a decrease in enzyme activity, in a dose- and time-dependent manner. Heme content decreased during desferrioxamine treatment of the cells. Addition of ferric ion-nitrilotriacetate [Fe (III)NTA] to desferrioxamine-containing cultures led to restoration of the reduction in the enzyme activity. While RNA blots showed that the amount of ferrochelatase mRNA remained unchanged during these treatments, the amount of ferrochelatase decreased with a concomitant decrease in enzyme activity. When full-length human ferrochelatase was expressed in Cos7 cells, the activity was found mainly in the mitochondria and was decreased markedly by treatment with desferrioxamine. The activity in Cos7 cells expressing human ferrochelatase in cytoplasm decreased with desferrioxamine, but to a lesser extent. When Escherichia coli ferrochelatase, which lacks the iron-sulfur cluster, was expressed in Cos7 cells, the activity did not change following any treatment. Conversely, the addition of Fe (III)NTA to the culture of K562 and Cos7 cells led to an increase in ferrochelatase activity. These results indicate that the expression of mammalian ferrochelatase is regulated by intracellular iron levels, via the iron-sulfur cluster center at the C-terminus, and this contributes to the regulation of the biosynthesis of heme at the terminal step.

Metallothionein III (MT-III) is a brain-specific member of the metallothionein family and binds zinc in vivo. In order to confirm the precise localization of MT-III in normal rat brain and the change of MT-III expression after transient whole brain ischemia, we raised a high affinity phagemid-antibody specific for rat MT-III. Immunohistochemical analysis revealed that MT-III in normal brain is localized abundantly in neuronal cell bodies in CA1-3 regions of hippocampus, dentate gyrus, cerebral cortex, olfactory bulb and Purkinje cells in cerebellum. This expression pattern of MT-III was similar to that of MT-III mRNA observed by in situ hybridization studies. ELISA and Northern blot analysis revealed that MT-III protein as well as mRNA levels were up-regulated in cerebrum soon after ischemic stress. Immunohistochemical analysis also demonstrated intense staining in neurons in injured brain after ischemia, which distributed in the same regions as in normal brain. These results suggest that MT-III plays an important role in protecting neurons from ischemic insult by reducing neurotoxic zinc levels and inhibits uncontrolled growth of neurites after ischemia.

The induction of metallothionein (MT) isoforms (MT-1, -2) by anticancer drugs was investigated in cultured rat hepatoma H4 II E C3 cells. The steady-state expression of MT-1 mRNAs was higher than that of MT-2 mRNAs. During incubation of the cells with various anticancer drugs, namely, adriamycin, epirubicin, cis-diamminedichloroplatinum(II) (CDDP), and cis-diammine(1, 1-cyclobutyldicarboxylato)platinum(II), both MT-1 and MT-2 mRNAs were coordinately inducible: the levels of isoMT mRNA reached a maxim of approximate by 6-fold at 3 h. Immunofluorescent studies revealed that the cytosolic fluorescence in the cells exposed to 1 microM CDDP for 48 h was more intensified than that in the untreated cells. Transfer of antisense oligonucleotides resulted in marked reduction of isoMT mRNA, and upon exposure to 5 microM CDDP for 48 h, the viabilities of these cells dropped to 25.8% of the controls. These results indicate that anticancer drugs are potent inducers of MT isoforms in hepatoma cells and that a decrease in cellular MTs enhances the susceptibility of hepatoma cells to CDDP. Thus, we conclude that endogenous MTs play a role in determining the sensitivity or resistance of cancer cells to clinically important anticancer agents.

Ca2+-sensitive adenylyl cyclases are key integrators of Ca2+ and cAMP signaling. To selectively probe dynamic changes in [Ca2+]i at the plasma membrane where adenylyl cyclases reside, a full-length, Ca2+-inhibitable type VI adenylyl cyclase/aequorin chimera has been constructed by a two-stage polymerase chain reaction method. The expressed adenylyl cyclase/aequorin chimera was appropriately localized to the plasma membrane, as judged by biochemical fractionation and functional analysis. The chimera retained full adenylyl cyclase activity and sensitivity to inhibition by physiological [Ca2+]i elevation. The aequorin portion of the chimeric construct was also capable of measuring changes in [Ca2+] both in vitro and in vivo. When the plasma membrane-tagged aequorin and cytosolic aequorin were compared in their measurement of [Ca2+]i, they showed contrasting sensitivities depending on whether the [Ca2+]i originated from internal stores or capacitative entry. This is the first full-length enzyme-aequorin chimera that retains the full biological properties of both aequorin and a Ca2+-sensitive adenylyl cyclase. This novel chimeric Ca2+ sensor provides the unique ability to directly report the dynamics of [Ca2+]i that regulates this Ca2+-sensitive enzyme under a variety of physiological conditions. Since this chimera is localized to the plasma membrane, it can also be used to assess local changes in [Ca2+]i at the plasma membrane as distinct from global changes in [Ca2+]i within the cytosol.

We investigated the effects of aminoguanidine, a relatively selective inhibitor of inducible nitric oxide (NO) synthase, on the systemic inflammatory response syndrome induced by platelet activating factor (PAF) and by lipopolysaccharide in rats, with emphasis on NO production in vivo. Aminoguanidine treatment improved survival rates after lipopolysaccharide challenge, whereas it aggravated the lethality caused by PAF. Lipopolysaccharide induced a marked increase in the concentrations of nitrate and nitrite in plasma compared with vehicle administration, and the increase was prevented by aminoguanidine. In contrast, PAF challenge with or without aminoguanidine did not affect the concentrations of nitrate and nitrite in plasma compared with vehicle administration. These results suggest that NO derived from inducible NO synthase is not a major participant in the systemic inflammatory response syndrome induced by PAF. Aminoguanidine is not likely to provide beneficial effects in conditions where PAF is produced and the concentrations of nitrate and nitrite in plasma are not significantly increased.

Objective: To investigate the role of superoxide and nitric oxide in platelet-activating factor-induced acute lung injury, hypotension, and mortality., Design: Prospective, randomized, controlled, experimental study., Setting: University research laboratory., Subjects: Anesthetized male Wistar rats (180 to 220 g) were studied., Interventions: In the first set of experiments, animals were divided into three groups. Group 1 received platelet-activating factor (2 microg/kg i.v.). Group 2 received recombinant human superoxide dismutase (50,000 U/kg i.v.) 30 mins before platelet-activating factor injection. Group 3 received vehicle agents. In the second set of experiments, animals were divided into six groups that received N(G)-nitro-L-arginine (L-NNA), a selective inhibitor of nitric oxide synthesis, or L-arginine, the physiologic precursor of nitric oxide synthesis: a) vehicles (i.v.); b) vehicle plus L-arginine (100 mg/kg i.v.); c) vehicle plus L-NNA (10 mg/kg i.v.); d) vehicle plus platelet-activating factor (2 microg/kg i.v.); e) L-arginine plus platelet-activating factor; and f) L-NNA plus platelet-activating factor. The first intravenous administration was given 5 mins before the second intravenous injection for each group., Measurements and Main Results: In the first set of experiments, vascular labeling with Monastral blue B demonstrated diffuse microvascular injury in the alveolar capillary beds 2 hrs after platelet-activating factor challenge. Thiobarbituric acid-reactive substances in the lung significantly increased at 2 hrs after platelet-activating factor injection. Platelet-activating factor treatment also resulted in an increased concentration of total protein, albumin, and Evans blue dye in bronchoalveolar lavage fluid at 2 hrs after administration, suggesting platelet-activating factor induction of increased alveolar permeability. The platelet-activating factor-induced alveolar microvascular injury, lipid peroxidation, and increased alveolar permeability were inhibited by pretreatment with recombinant human superoxide dismutase. Although L-NNA alone did not affect alveolar permeability in the second set of experiments, L-NNA treatment before platelet-activating factor challenge significantly aggravated platelet-activating factor-induced increased alveolar permeability 2 hrs after platelet-activating factor challenge. Platelet-activating factor also produced a rapid decrease in blood pressure that was not ameliorated by treatment with L-NNA. However, L-NNA pretreatment was associated with a significant increase in platelet-activating factor-caused mortality within 6 hrs. All rats survived with L-arginine treatment before platelet-activating factor challenge. L-NNA treatment decreased nitrate/nitrite concentration, an index of total nitric oxide production, in plasma., Conclusions: These results indicate that superoxide, the derived active oxygen species, and lipid peroxidation are implicated in the pathogenesis of platelet-activating factor-induced acute lung injury. Nitric oxide does not play a major role in platelet-activating factor-induced hypotension. Nitric oxide appears to play a protective role in the acute lung injury and mortality induced by platelet-activating factor.

Maintenance by the endothelium of a semi-permeable barrier is critically important in the exchange of oxygen and carbon dioxide in the lung. Intracellular free Ca2+ ([Ca2+]i) and cAMP are principal determinants of endothelial cell barrier function through their mutually opposing actions on endothelial retraction. However, details of the mechanisms of this antagonism are lacking. The recent discovery that certain adenylyl cyclases (EC 4.6.1.1) could be acutely inhibited by Ca2+ in the intracellular concentration range provided one possible mechanism whereby elevated [Ca2+]i could decrease cAMP content. This possibility was explored in pulmonary artery endothelial cells. The results indicate that a type VI Ca(2+)-inhibitable adenylyl cyclase exists in pulmonary artery endothelial cells and is modulated by physiological changes in [Ca2+]i. Furthermore, the results suggest the inverse relationship between [Ca2+]i and cAMP that is established by Ca(2+)-inhibitable adenylyl cyclase plays a critical role in modulating pulmonary artery endothelial cell permeability. These data provide evidence that susceptibility to inhibition of adenylyl cyclase by Ca2+ can be exploited in modulating a central physiological process.

Purpose: Modified Gianturco Z stents were used in five patients with hilar cholangiocarcinoma to permit bilobar hepatic drainage via a single percutaneous tract., Patients and Methods: After successful negotiation of strictures from the ipsilateral hepatic duct to the contralateral hepatic duct and the common bile duct, a modified endoprosthesis--made by connecting two double-body Z stents with two stainless steel wires in order to leave a space in between--was implanted in one stricture and a 'space' was located at the hepatic confluence. A second endoprosthesis, a two- to six-body Z stent, was introduced into the second stricture through the 'space' of the initial endoprosthesis and was implanted so that a part of the endoprosthesis should overlap the initial endoprosthesis., Results: Optimal positioning of the two endoprostheses was successful in all patients., Conclusion: The technique seems simple, safe, and reliable in reconstructing the bilateral hepatic ductal systems via a single percutaneous approach in patients with hilar cholangiocarcinoma.

We investigated the molecular basis of ferrochelatase in a Japanese patient with erythropoietic protoporphyria (EPP), complicated by fatal liver failure, and defined a novel point mutation in the ferrochelatase gene. cDNAs were synthesized using Epstein-Barr-virus-transformed lymphoblastoid cells from the proband. cDNA clones encoding ferrochelatase in the proband were isolated by amplification using the polymerase chain reaction. There were two sizes of ferrochelatase cDNAs; one was normal in size, the other being smaller. Sequence analysis of the abnormally sized cDNA clones revealed that they lacked exon 9 of the ferrochelatase gene. Genomic DNA analysis demonstrated that the proband had the abnormal allele and that it contained a G to A point mutation at the first position of the donor site of intron 9. An identical mutation was detected in the affected family members of the proband by allele-specific oligonucleotide hybridization analysis. EPP is inherited in an autosomal dominant manner in this family.

A 70-year-old man with Hashimoto's disease had selective IgM deficiency, while other immunoglobulin levels were normal. In vitro mixing experiments were carried out in which B cells and T cells from the patient and from a healthy control donor were co-cultured in the presence of pokeweed mitogen, in order to investigate the etiology of IgM hypoproduction. The results indicated that the patient had B-cell dysfunction, involving the impairment of B-cell differentiation. In addition, both IgG of the healthy control donor and thyroid hormone may play important roles in the pathogenesis of this case.

The effect of biliary endoprosthesis was evaluated in 13 patients with major bile duct obstruction secondary to invasion by hepatocellular carcinoma. In 12 patients major portal vein branches were also invaded by the tumors. After several days' instillation of nasobiliary or percutaneous drainage tubes to flush the bile ducts, biliary endoprosthesis was performed either endoscopically (N = 9) or percutaneously (N = 4). Significant decrease (less than 50% of initial values) of alkaline phosphatase and bilirubin levels was observed in eight and two patients on day 20, respectively. Twelve patients died of hepatic failure at 27-132 days (mean 60 days). One patient without portal vein involvement is currently alive at 300 days. Biliary endoprosthesis has a limited role in the palliation of bile duct obstruction secondary to hepatocellular carcinoma, and the prognosis may be influenced mainly by the underlying hepatic function.

We have determined the structure of the human ferrochelatase gene after isolation and characterization of lambda phage clones mapping discrete regions of the cDNA. This gene was assigned to human chromosome 18 at region q21.3, by fluorescent in situ hybridization. The gene contains a total of 11 exons and has a minimum size of about 45 kb. The exon/intron boundary sequences conform to consensus acceptor (GTn) and donor (nAG) sequences, and the exons in the gene appear to encode functional protein domains. A major site of the transcription initiation, determined by S1 nuclease mapping, was assigned to an adenine base 89 bases upstream from the adenine base of the translation initiation ATG. The promoter region contains a potential binding site for Sp1, NF-E2 and erythroid-specific transcriptional factor GATA-1, but not a typical TATAA or CCAAT sequence. Analysis of primer extension showed that the transcription starts at the same position between hepatoma HepG2 and erythroleukemia K562 cell mRNA, thereby suggesting that there can be a single transcript in erythroid and non-erythroid cells.

The molecular basis of an inherited defect of ferrochelatase in a patient with erythropoietic protoporphyria (EPP) was investigated. Ferrochelatase is the terminal enzyme in the heme biosynthetic pathway and catalyzes the insertion of ferrous iron into protoporphyrin IX to form heme. In Epstein-Barr virus-transformed lymphoblastoid cells from a proband with EPP, enzyme activity, an immunochemically quantifiable protein, and mRNA content of ferrochelatase were about one-half the normal level. In contrast, the rate of transcription of ferrochelatase mRNA in the proband's cells was normal, suggesting that decreased ferrochelatase mRNA is due to an unstable transcript. cDNA clones encoding ferrochelatase in the proband, isolated by amplification using the polymerase chain reaction, were found to be classified either into those encoding the normal protein or into those encoding an abnormal protein that lacked exon 2 of the ferrochelatase gene, indicating that the proband is heterozygous for the ferrochelatase defect. Genomic DNA analysis revealed that the abnormal allele had a point mutation, C----T, near the acceptor site of intron 1. This point mutation appears to be responsible for the post-transcriptional splicing abnormality resulting in an aberrant transcript of ferrochelatase in this patient.

The cDNA encoding human ferrochelatase [EC 4.99.1.1] was isolated from a human placenta cDNA library in bacteriophage lambda gt11 by screening with a radiolabeled fragment of mouse ferrochelatase cDNA. The cDNA had an open reading frame of 1269 base pairs (bp) encoding a protein of 423 amino acid residues (Mr. 47,833) with alternative putative polyadenylation signals in the 3' non-coding regions and poly (A) tails. Amino acid sequencing showed that the mature protein consists of 369 amino acid residues (Mr. 42,158) with a putative leader sequence of 54 amino acid residues. The human enzyme showed an 88% identity to mouse enzyme and 46% to yeast enzyme. Northern blot analysis showed two mRNAs of about 2500 and 1600 bp for ferrochelatase in K562 and HepG2 cells. As full-length cDNA for human ferrochelatase is now available, molecular lesions related to erythropoietic protoporphyria can be characterized.

The cDNA encoding mouse ferrochelatase (protoheme ferrolyase, EC 4.99.1.1) was isolated from a mouse erythroleukemia (MEL) cell cDNA library in lambda gt11 expression vector, by immunoscreening with a polyclonal antibody. Two full-length clones containing cDNA inserts of 2.2 and 2.90 kilobases were obtained. These clones have the same entire enzyme coding region, but alternative putative polyadenylation sites in the 3'-noncoding regions. From the deduced primary structure, a putative leader sequence of 53 amino acid residues resulted in a precursor protein of 420 amino acid residues (Mr 47,130) and a mature protein of 367 residues (Mr 41,692). The cDNA allows for the expression of active ferrochelatase by transfected culture cells. RNA blot analysis showed two species of ferrochelatase mRNA consistent with findings of two polyadenylation sites. Both the mRNAs increased by treatment of the MEL cells with dimethyl sulfoxide. The band pattern of the RNA of the mouse liver was the same as that of the MEL cells. Based on these results, we deduce that ferrochelatase in erythroid and hepatic cells can be only of one type.

Ferrochelatase from bovine kidney mitochondria has been purified 1600-fold with a 6.5% yield, exhibiting a specific activity of 490 nmol mesoheme formed/mg of protein per min. The Km values for mesoporphyrin IX and protoporphyrin IX with iron were 12.5 and 12.7 microM, respectively. The Km values for iron and zinc with mesoporphyrin IX were 3.51 and 3.17 microM, respectively. The purified enzyme showed a single band with an apparent molecular mass of 42,000 daltons (42 kDa) on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The rabbit antibody against the purified enzyme markedly inhibited activities of the enzyme from both the kidney and liver. Immunoblot analysis showed that the antibody reacted with the renal as well as the hepatic enzymes showing the same molecular weight. Peptide mapping with trypsin or alpha-chymotrypsin showed that digested peptides of renal enzyme were similar to those of hepatic enzyme. Ferrochelatase activity in mouse erythroleukemia (MEL) cells increased in parallel with an increase of heme synthesis by treatment with dimethylsulfoxide. Using immunoblotting techniques, the amount of the enzyme in the MEL cells has been shown to increase by the induction, showing a molecular mass of 41 kDa which was the same as that of the mouse hepatic enzyme. Comparative structural analysis of the enzyme of MEL cells and that of mouse liver by peptide mapping showed that the partial digestive peptides of both enzymes exhibited a similar pattern. These results strongly suggest that ferrochelatase in kidney, liver and erythroid cells can be of one type.