[Laparoscopic Abdominoperineal Resection of the Rectum in a Case with Pagetoid Spread of Anal Canal Carcinoma]

The patient, a man in his 60s, first noticed an elevated lesion around the anus 3 years ago. The lesion failed to subside with the topical drug preparations prescribed at a local clinic, and the patient was referred to the Department of Dermatology of our hospital for further workup and treatment. The findings of biopsy from the lesion suggested skin infiltration of anal canal carcinoma, and the patient was referred to the Department of Surgery. Examination here revealed only induration of the anal canal, with no abnormality of the rectal mucosa even when the endoscope was reversed to visualize the rectum. Examination by various imaging modalities failed to reveal any metastases to the lymph nodes or distant organs, and the primary lesion remained unidentified. Laparoscopic abdominoperineal excision of the rectum was performed, beginning with anal manipulation. First, a 15-mm margin was set on the skin from the tumor edge, and the skin stump was divided into 4 equal portions. After confirming by rapid intraoperative frozen-section examination that the margin was negative along the full circumference, anal manipulation was performed, leaving a distance in the vertical direction immediately below the tumor. Upon completion of the anal manipulation, intraperitoneal manipulation was performed in a routine manner. The anal skin was relaxed subcutaneously, as done during mastectomy, and the subsequent suture closure could be done smoothly. The tumor was classified as pT1bN0M0, pStage Ⅰ. The experience with this case indicates that biopsy should be proactively employed for the diagnosis in such cases, and that proactive skin biopsy is useful when dealing with intractable anal skin lesions.

IgM to IgG Class Switching Is a Necessary Step for Pemphigus Phenotype Induction in Desmoglein 3-Specific B Cell Receptor Knock-in Mouse

Pemphigus vulgaris is an autoimmune blistering disease caused by IgG targeting desmoglein 3 (Dsg3), an adhesion molecule of keratinocytes. Anti-Dsg3 IgG production is prevented in healthy individuals, but it is unclear how Dsg3-specific B cells are regulated. To clarify the immunological condition regulating Dsg3-specific B cells, a pathogenic anti-Dsg3 Ig (AK23) knock-in mouse was generated. AK23 knock-in B cells developed normally without undergoing deletion or acquiring an anergic phenotype in vivo. The knock-in B cells showed Ca²⁺ influx upon IgM cross-linking and differentiated into AK23-IgG⁺ B cells after LPS and IL-4 stimulation in vitro that induced a pemphigus phenotype after adoptive transfer into Rag2 ^-/- mice. However, the knock-in mouse itself produced AK23-IgM but little IgG without blisters in vivo. Dsg3 immunization and skin inflammation caused AK23-IgG production and a pemphigus phenotype in vivo. Furthermore, Fcgr2b deficiency or haploinsufficiency spontaneously induced AK23-IgG production and a pemphigus phenotype with poor survival rates in AK23 knock-in mice. To assess Fcgr2b involvement in Ig class-switch efficiency, postswitch transcripts of B cells were quantified and significantly higher in Fcgr2b ^-/- and Fcgr2b ^+/- mice than wild-type mice in a gene dose-dependent manner. Finally, RNA sequencing revealed reduced expression of FCGR2B and FcγRIIB-related genes in patient B cells. These results indicated that Dsg3-specific B cells do not spontaneously perform pathogenic class switching in vivo, and pemphigus phenotype induction was prevented under normal conditions. Attenuated FcγRIIB signaling is also one of the drivers for pathogenic class switching and is consistent with immunological features identified from clinical samples. This study unveiled a characteristic immune state silencing autoreactive B cells in mice.

Intravenous Ig Regulates Anti-Desmoglein 3 IgG Production in B220- Antibody-Producing Cells in Mice with Pemphigus Vulgaris

Intravenous Ig (IVIG) is a treatment option for intractable cases of pemphigus vulgaris (PV), an autoimmune blistering disease caused by autoantibodies against desmoglein 3 (DSG3). To investigate the efficacy of IVIG on autoantibody secretion, we produced PV model mice by adoptive transfer of immunized Dsg3^-/- splenocytes to Rag2^-/- mice. We found that circulating anti-DSG3 IgG ELISA titer decreased in PV model mice after 5 days of treatment with IVIG compared with PBS-treated mice, whereas the F(ab')₂ fragment did not suppress the anti-DSG3 IgG titer. enzyme-linked immunospot assay revealed that IVIG treatment reduced the frequency of anti-DSG3 antibody-secreting cells in the spleen but not in lymph nodes and bone marrow. Moreover, this reduction was observed only in the splenic B220^- fraction but not in the B220⁺ fraction. Furthermore, IVIG decreased the serum levels of anti-DSG3 IgG, even after a significant reduction of its titer, owing to antibody-mediated CD20⁺ B cell depletion. In addition, IVIG suppressed anti-DSG3 IgG production in B220^-CD138⁺ plasma cells derived from PV model mice ex vivo. These results indicate that IVIG reduced autoantibody production in B220^- cells containing plasma cells in PV model mice, and this function may indicate one of the mechanisms of action of IVIG on PV.

Cholesterol 25-hydroxylase is a metabolic switch to constrain T cell-mediated inflammation in the skin

Interleukin-27 (IL-27) is an immunoregulatory cytokine whose essential function is to limit immune responses. We found that the gene encoding cholesterol 25-hydroxylase (Ch25h) was induced in CD4⁺ T cells by IL-27, enhanced by transforming growth factor–β (TGF-β), and antagonized by T-bet. Ch25h catalyzes cholesterol to generate 25-hydroxycholesterol (25OHC), which was subsequently released to the cellular milieu, functioning as a modulator of T cell response. Extracellular 25OHC suppressed cholesterol biosynthesis in T cells, inhibited cell growth, and induced nutrient deprivation cell death without releasing high-mobility group box 1 (HMGB1). This growth inhibitory effect was specific to actively proliferating cells with high cholesterol demand and was reversed when extracellular cholesterol was replenished. Ch25h-expressing CD4⁺ T cells that received IL-27 and TGF-β signals became refractory to 25OHC-mediated growth inhibition in vitro. Nonetheless, IL-27–treated T cells negatively affected viability of bystander cells in a paracrine manner, but only if the bystander cells were in the early phases of activation. In mouse models of skin inflammation due to autoreactive T cells or chemically induced hypersensitivity, genetic deletion of Ch25h or Il27ra led to worse outcomes. Thus, Ch25h is an immunoregulatory metabolic switch induced by IL-27 and dampens excess bystander T effector expansion in tissues through its metabolite derivative, 25OHC. This study reveals regulation of cholesterol metabolism as a modality for controlling tissue inflammation and thus represents a mechanism underlying T cell immunoregulatory functions.

Autoimmunity and immunological tolerance in autoimmune bullous diseases

Autoimmune diseases are devastating conditions in which the immune system is directed against the host, leading to life-threatening destruction of organs. Although autoantigens are ill-defined in most autoimmune diseases, this is not the case in the skin. Autoimmune bullous diseases have been extensively studied with detailed characterization of autoantigens, the epitopes that are targeted, and the mechanisms of action that mediate autoimmune tissue destruction. Pemphigus is an autoimmune bullous disease caused by circulating IgG that targets two desmosomal proteins, desmoglein 1 and 3, which are crucial for cell-cell adhesion of keratinocytes. Binding of auto-antibodies to desmogleins impairs keratinocyte adhesion, leading to severe blistering disease. Mouse models that recapitulate the human disease have been instrumental in elucidating the detailed pathophysiology. Taking advantage of the fact that desmogleins are specifically targeted in pemphigus, studying humoral and cellular autoimmunity against these autoantigens provides us with an opportunity to understand not only the effector mechanisms of B and T cells in mediating pathology but also how autoreactive lymphocytes are regulated during development in the thymus and post-development in the periphery. This review introduces pemphigus and its subtypes as prototypic autoimmune diseases from which recent basic and translational developments should provide insight into how autoimmunity develops.

Basement membrane zone IgE deposition is associated with bullous pemphigoid disease severity and treatment results

BACKGROUND

A subset of patients with bullous pemphigoid (BP) show deposition of IgE in the basement membrane zone (BMZ), yet the relationship between BMZ IgE and the clinical presentation of BP remains unclear.

OBJECTIVES

To investigate the relationship between IgE deposition, IgE levels in serum, and disease severity in patients with BP.

METHODS

We investigated IgE autoantibodies in 53 patients with BP by direct immunofluorescence (DIF), indirect immunofluorescence and enzyme-linked immunosorbent assay.

RESULTS

Of 53 patients with BP, 23 (43%) had IgE deposition, 10 (19%) of whom were IgE+ and 13 (25%) IgE± according to DIF analyses. Erosion/blister (E/B) Bullous Pemphigoid Disease Area Index (BPDAI) scores were significantly higher in IgE+ patients than in IgE- patients (n = 15), while no significant differences were found for urticaria/erythema BPDAI scores. IgE+ and IgE± patients took longer to reduce their E/B BPDAI score by 75% after systemic corticosteroid treatment. BP180-IgE levels were significantly higher among IgE+ patients than IgE± or IgE- patients (n = 10). Total IgE levels in the serum and blood eosinophil counts did not differ between IgE+, IgE± and IgE- patients. A significant correlation was detected between BP180-IgG and BP180-IgE, but not between BPDAI scores and any of BP180-IgG, BP180-IgE or blood eosinophil count.

CONCLUSIONS

IgE deposition in the BMZ is associated with higher E/B BPDAI scores and longer treatment periods. We conclude that IgE binding in the BMZ may contribute to BP pathogenesis by promoting blister formation. What's already known about this topic? BP180-IgE autoantibodies have an important role in the pathogenesis of bullous pemphigoid (BP). A subset of patients with BP display deposition of IgE within the basement membrane zone (BMZ) of skin tissue. What does this study add? Patients with in vivo IgE deposition in the BMZ displayed higher erosion/blister Bullous Pemphigoid Disease Area Index (BPDAI) scores, while urticaria/erythema BPDAI scores were not significantly different. Patients with in vivo IgE deposition in the BMZ took longer to reduce their erosion/blister BPDAI score by 75% after systemic corticosteroid treatment. BP180-specific IgE levels in serum were higher among patients with linear IgE deposition in the BMZ than in those with granular or no IgE deposition.

Managing the challenges of a highly pathogenic avian influenza H5N8 outbreak in Uganda: a case study

In 2016-2017, the H5N8 strain of highly pathogenic avian influenza (HPAI) spread worldwide and Uganda reported the first occurrence of the disease in its poultry and wild birds. Genetic analysis revealed that the virus clusters with 2.3.4.4 group B strains from birds in central and southern Asia, and thus forms part of the 2.3.4.4 group B clade. Since Uganda is in the path of two major migratory bird flyways, it is likely that infected migratory wild birds played a crucial role in the introduction of H5N8 HPAI viruses into Uganda. The outbreaks happened in the districts of Wakiso, Masaka and Kalangala and affected domestic and wild birds. A One Health Multisectoral Coordination Committee, consisting of a National Task Force, Technical Working Groups and District Disaster Management Committees, was immediately activated to coordinate the preparedness and response efforts to control the disease. In all the affected districts, surveillance was intensified on both domestic and wild birds; biosecurity measures were increased; and movement controls, culling, cleaning, disinfection and safe disposal of carcasses were implemented. Awareness of the disease was raised through education materials, leaflets and brochures distributed to farmers. Finally, Uganda successfully controlled the H5N8 outbreak, using its national preparedness and response mechanisms and through collaboration with international partners. The emergence and spread of this virus strain in Uganda and other parts of Africa poses a significant threat to the poultry industry and food security.

Assessment of biological, psychological and adherence factors in the prediction of step-down treatment for patients with well-controlled asthma

BACKGROUND AND OBJECTIVE

Inhaled corticosteroids (ICS) and inhaled corticosteroids combined with long-acting beta2-agonist (ICS/LABA) are standard treatments for asthma. However, factors that might help reduce medication in well-controlled asthma are unknown. We classified problems of asthma patients into biological, psychological and adherence factors, and investigated factors associated with the indication and failure of a medication step-down treatment.

METHODS

Two hundred twenty two well-controlled asthma patients receiving ICS or ICS/LABA were assessed for physical and psychiatric problems and followed up for one year from adjustment of their treatment step. Factor B was defined as a presence of chronic upper airway complications. Factor P was defined as presence of psychiatric complications such as sleep disorder, depression, anxiety and somatoform disorders. Factor A was defined as poor adherence to ICS or ICS/LABA inhaler of 75% or less. Success in step-down treatment was defined as maintenance of well-controlled status for over one year after step-down.

RESULTS

Factor B was the most important single negative predictive factor for indication for step-down treatment (Odds ratio; 0.19). Factor A increased the risk of failure to maintain step-down treatment most significantly by 23-fold, and factor B increased it by 11-fold. The combination of factors B and A increased failure by 24-fold, factors P and A by 21-fold, all three factors by 36-fold. Factor P only interacted with the other factors to reduce chances of stepping down, but did not constitute a problem factor when present alone.

CONCLUSION AND CLINICAL RELEVANCE

The evaluation of biological, psychological and adherence problems may lead to a more proactive and targeted approach to step-down treatment for patients with well-controlled asthma.

Origin and evolution of highly pathogenic H5N1 avian influenza in Asia

Outbreaks of highly pathogenic avian influenza caused by H5N1 viruses were reported almost simultaneously in eight neighbouring Asian countries between December 2003 and January 2004, with a ninth reporting in August 2004, suggesting that the viruses had spread recently and rapidly. However, they had been detected widely in the region in domestic waterfowl and terrestrial poultry for several years before this, and the absence of widespread disease in the region before 2003, apart from localised outbreaks in the Hong Kong Special Autonomous Region (SAR), is perplexing. Possible explanations include limited virus excretion by domestic waterfowl infected with H5N1, the confusion of avian influenza with other serious endemic diseases, the unsanctioned use of vaccines, and the under-reporting of disease as a result of limited surveillance. There is some evidence that the excretion of the viruses by domestic ducks had increased by early 2004, and there is circumstantial evidence that they can be transmitted by wild birds. The migratory birds from which viruses have been isolated were usually sick or dead, suggesting that they would have had limited potential for carrying the viruses over long distances unless subclinical infections were prevalent. However, there is strong circumstantial evidence that wild birds can become infected from domestic poultry and potentially can exchange viruses when they share the same environment. Nevertheless, there is little reason to believe that wild birds have played a more significant role in spreading disease than trade through live bird markets and movement of domestic waterfowl. Asian H5N1 viruses were first detected in domestic geese in southern China in 1996. By 2000, their host range had extended to domestic ducks, which played a key role in the genesis of the 2003/04 outbreaks. The epidemic was not due to the introduction and spread of a single virus but was caused by multiple viruses which were genotypically linked to the Goose/GD/96 lineage via the haemagglutinin gene. The H5N1 viruses isolated from China, including the Hong Kong SAR, between 1999 and 2004 had a range of genotypes and considerable variability within genotypes. The rising incidence and widespread reporting of disease in 2003/04 can probably be attributed to the increasing spread of the viruses from existing reservoirs of infection in domestic waterfowl and live bird markets leading to greater environmental contamination. When countries in the region started to report disease in December 2003, others were alerted to the risk and disease surveillance and reporting improved. The H5N1 viruses have reportedly been eliminated from three of the nine countries that reported disease in 2003/04, but they could be extremely difficult to eradicate from the remaining countries, owing to the existence of populations and, possibly, production and marketing sectors, in which apparently normal birds harbour the viruses.

Use of illegal drugs among mothers across racial/ethnic groups in the United States: a multi-level analysis of individual and community level influences

OBJECTIVE

To obtain adjusted one-year prevalence estimates and compare multi-level correlates of marijuana, cocaine, crack, or heroin use among 4,678 mothers of minor children in the United States across racial/ethnic populations.

METHODS

The study used publicly available data from the 1997 National Household Survey on Drug Abuse. Hierarchical generalized linear modeling (HGLM) procedures were used to test drug use variation among non-Hispanic White, non-Hispanic Black, and Hispanic mothers across US neighborhoods.

RESULTS

Black mothers were 40% less likely to use illegal drugs than were White mothers, and Hispanic mothers were 72% less likely than were White mothers to use drugs, after adjusting for demographic and community covariates. Drug use was found to vary across neighborhoods for all racial/ethnic groups. This study identified a positive association between the likelihood of mothers using illegal drugs and their living in neighborhoods with a higher occurrence of drug use.

CONCLUSION

To compare drug use across racial/ethnic groups, it is necessary to account for the confounding effects of covariates. Additional research is needed to determine whether non-drug using mothers chose to live in neighborhoods with a lower concentration of drug use, whether residence in these neighborhoods decreases the likelihood of mothers using drugs, or if a reciprocal relationship exists. The mechanisms that link individual drug use and neighborhood characteristics merit further investigation.

Increased constriction of the ductus arteriosus with combined administration of indomethacin and L-NAME in fetal rats

We studied age-related changes and the caliber of the ductus arteriosus (DA) after two-pathway inhibition of prostaglandin E(2) and nitric oxide (NO) by the combined administration of indomethacin, a cyclooxygenase inhibitor, and N(G)-nitro-L-arginine methyl ester (L-NAME), an NO synthase inhibitor, in fetal rats. Pregnant rats from day 18 to 21 of gestation were used. They were administered indomethacin orally (3 mg/kg) 3 h before cesarean section, and then L-NAME (50 mg/kg) was injected intraperitoneally 3 h before the rats were killed. Using rapid-freezing and shaving methods, the caliber of the DA in fetal rats was measured. Compared with the indomethacin alone group, indomethacin plus L-NAME further constricted the DA after indomethacin and L-NAME were simultaneously administered 3 h before the rats were sacrificed. The extent of the final DA constriction was almost equal to the addition of each effect of indomethacin and L-NAME. We concluded that the magnitude of DA constriction following indomethacin plus L-NAME was due to the additive effects of these agents, suggesting a possible method to treat patent DA in premature infants.

Sociomedical aspects of epileptic patients: their employment and marital status

We examined the employment and marital status of adult patients with epilepsy who did not have mental retardation and who had been treated at Hirosaki University Hospital, Hirosaki, Japan, for more than 5 years. The present study included 278 patients (142 males and 136 females) ranging from 20 to 60 years of age. We investigated the occupational status of the subjects and found that 168 had permanent jobs, but 41 patients were unemployed at the time of this survey. The proportion of the patients whose seizures were controlled at the time of this survey was 68% (114/168) in the group having permanent jobs, and 22% (9/41) in the unemployed group. Forty cases answered that they had resigned from their jobs due to occurrence of epileptic seizures. Of these patients, 13 were dismissed and 27 resigned voluntarily due to the potential for seizures. As to relationship between jobs and neuropsychiatric complications, the incidence of a past history of psychotic states in the unemployed group was significantly higher than that in the employed group. As to marital status, 13 males and 16 females (n = 29) had experienced divorce. Seven cases (two males and five females) had answered that epilepsy had been the reason for their divorce. We conclude that epilepsy or epileptic seizures have various negative effects on the patient's social life.

Adenosine receptor subtypes modulate two major functional pathways for hippocampal serotonin release

To clarify the mechanisms of interaction between adenosine A(1) receptor (A1-R) and adenosine A(2) receptor (A2-R) on neurotransmitter release, this study determined the functional interactions among adenosine receptors (AD-Rs), voltage-sensitive Ca(2+) channels (VSCCs), protein kinases (PKs), and synaptic proteins [N-ethylmaleimide-sensitive factor (NSF) attachment protein (SNAP) receptors] on hippocampal serotonin release using in vivo microdialysis in freely moving rat. Basal serotonin release was regulated by two functional complexes: N-type VSCC (N-VSCC)/calcium-phospholipid-dependent protein kinase (PKC)/syntaxin (major pathway) and P-type VSCC (P-VSCC)/cyclic AMP-dependent protein kinase (PKA)/synaptobrevin (minor pathway). However, K(+)-evoked serotonin release was regulated by N-VSCC/PKC/syntaxin (minor pathway) and P-VSCC/PKA/synaptobrevin (major pathway). A1-R antagonists increased basal serotonin release, which was reduced by inhibitors of N-VSCC, PKC, and syntaxin predominantly and by inhibitors of PKA and synaptobrevin weakly, but was not affected by P-VSCC inhibitor. In the presence of A1-R antagonist, A2-R agonists increased basal serotonin release, which was inhibited by inhibitors of P-VSCC, PKA, and synaptobrevin predominantly and reduced by inhibitors of N-VSCC, PKC, and syntaxin weakly. Under the condition of activation of adenylate cyclase in the absence of A1-R antagonists, A2-R agonists increased basal serotonin release. A1-R antagonist and A2-R agonist enhanced K(+)-evoked serotonin release, which was inhibited by inhibitors of P-VSCC, PKA, and synaptobrevin predominantly. These results suggest that an activation of A1-R suppresses serotonin release via inhibition of both N-VSCC/PKC/syntaxin and P-VSCC/PKA/synaptobrevin pathways, and an activation of A2-R stimulates serotonin release via enhancement of the P-VSCC/PKA/synaptobrevin pathway. Therefore, PKA activity plays an important role in the interaction between A1-R and A2-R on hippocampal serotonin release.

Dysfunction of M-channel enhances propagation of neuronal excitability in rat hippocampus monitored by multielectrode dish and microdialysis systems

To explore the pathogenesis of benign familial neonatal convulsions (BFNC), we determined effects of KCNQ-related M-channels (KCNQ-channels) on hippocampal glutamate (Glu) and gamma-aminobutyric acid (GABA) releases using microdialysis, and propagation of evoked field-potentials (FP) using multielectrode (64-ch)-dish system as two-dimensional monitoring. KCNQ-channel inhibitor, Dup996, enhanced hippocampal K(+)-evoked Glu and GABA releases without affecting basal releases of them. Dup996 unaffected FP-amplitude, but enhanced FP-propagation. The GABA(A)-receptor antagonist, bicuculline, enhanced the stimulatory effects of Dup996 on FP-propagation, however, this stimulatory effects of Dup996 were abolished by the alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA)/glutamate-receptor antagonist, DNQX. These results suggest that the occurrence of BFNC cannot be produced by KCNQ-channel dysfunction alone, but by reciprocal action between impaired KCNQ-channel and other unknown elements (possibly dysfunction of inhibitory neurotransmission system).

Biphasic response of the ductus arteriosus to combined administration of indomethacin and L-NAME in fetal rats

We studied the combined effects of indomethacin, a cyclooxygenase inhibitor, and N(G)-nitro-L-arginine methyl ester (L-NAME), a nitric oxide (NO) synthase inhibitor, on the patency of the ductus arteriosus (DA) in fetal rats. Pregnant rats were administered indomethacin (3 mg/kg) orally 3 h before cesarean section, and then L-NAME (5 and 50 mg/kg), D-NAME, an enantiomer of L-NAME (50 mg/kg), or methylene blue, a soluble guanylate cyclase inhibitor (100 mg/kg), was injected intraperitoneally at various times before the cesarean section. Using rapid freezing and shaving methods, the calibers of the DA were measured. Compared with the indomethacin alone group, L-NAME caused a rapid and marked increase in the DA caliber 0.5 h after injection in fetal rats in which the DA was constricted by treatment with indomethacin. Subsequently, the transient ductal dilatation was completely reversed by 3 h after the L-NAME injection. Methylene blue also caused a biphasic response, but D-NAME did not affect the DA caliber. We conclude that the inhibition of both cyclooxygenase (indomethacin) and NO synthase (L-NAME) or NO action (methylene blue) causes a biphasic effect on the DA caliber in fetal rats.

Effects of butorphanol and carprofen on the minimal alveolar concentration of isoflurane in dogs

OBJECTIVE

To evaluate the effects of butorphanol and carprofen, alone and in combination, on the minimal alveolar concentration (MAC) of isoflurane in dogs.

DESIGN

Randomized complete-block crossover study.

ANIMALS

6 healthy adult dogs.

PROCEDURE

Minimal alveolar concentration of isoflurane was determined following administration of carprofen alone, butorphanol alone, carprofen and butorphanol, and neither drug (control). Anesthesia was induced with isoflurane in oxygen, and MAC was determined by use of a tail clamp method. Three hours prior to induction of anesthesia, dogs were fed a small amount of canned food without any drugs (control) or with carprofen (2.2 mg/kg of body weight [1 mg/lb]). Following initial determination of MAC, butorphanol (0.4 mg/kg [0.18 mg/lb], i.v.) was administered, and MAC was determined again. Heart rate, respiratory rate, indirect arterial blood pressure, endtidal partial pressure of CO2, and saturation of hemoglobin with oxygen were recorded at the time MAC was determined.

RESULTS

Mean +/- SD MAC of isoflurane following administration of butorphanol alone (1.03 +/- 0.22%) or carprofen and butorphanol (0.90 +/- 0.21%) were significantly less than the control MAC (1.28 +/- 0.14%), but MAC after administration of carprofen alone (1.20 +/- 0.13%) was not significantly different from the control value. The effects of carprofen and butorphanol on the MAC of isoflurane were additive. There were not any significant differences among treatments in regard to cardiorespiratory data.

CONCLUSIONS AND CLINICAL RELEVANCE

Results suggest that administration of butorphanol alone or in combination with carprofen significantly reduces the MAC of isoflurane in dogs; however, the effects of butorphanol and carprofen are additive, not synergistic.

Effects of carbamazepine on acetylcholine release and metabolism

To clarify the mechanisms of action of carbamazepine (CBZ), we investigated the effects of CBZ on acetylcholine (ACh) release and metabolism in rat striatum and hippocampus. Acute administration of effective dose of CBZ (25 mg/kg) increased both striatal and hippocampal extracellular levels of ACh, whereas a supraeffective dose of CBZ (50 mg/kg) did not affect the levels and a toxic dose of CBZ (100 mg/kg) decreased the extracellular ACh levels in both brain regions. Both acute and chronic administrations of CBZ (25 and 50 mg/kg, mg/kg per day) increased intracellular ACh levels in striatum and hippocampus. The striatal intracellular ACh levels were decreased by both acute and chronic administrations of CBZ (100 mg/kg, mg/kg per day), whereas the hippocampal intracellular ACh levels were not affected. The effective CBZ concentration did not affect cholinesterase activity, whereas supraeffective CBZ concentration reduced it weakly. Effective dose of CBZ enhanced ACh release and synthesis; however, supraeffective doses of CBZ reduced ACh release and synthesis without enhancement of ACh degradation, indicating that CBZ has biphasic effects on ACh release and synthesis. Thus, the present findings, the slight stimulation of ACh function by effective dose of CBZ, are involved, at least partially, in the antiepileptic and mood stabilizing mechanisms of action of CBZ.

Role of nitric oxide in regulating the ductus arteriosus caliber in fetal rats

The role of nitric oxide (NO) on the ductus arteriosus (DA) patency was examined in fetal rats at various stages of gestation. N(G)-nitro-L-arginine methyl ester (L-NAME, 50 mg/kg, i.p.), an NO synthase (NOS) inhibitor, or indomethacin (3 mg/kg, p.o.), a cyclooxygenase inhibitor, was administered at 3 hr before cesarean section to pregnant rats ranging from day 17 to day 21 of gestation. Dams were decapitated and the fetuses were obtained by cesarean section. The fetuses were rapidly frozen in an acetone-dry ice mixture. Using rapid-freezing and shaving methods, the calibers of the DA and pulmonary artery were measured. The constrictive effect of L-NAME on the fetal DA caliber was stronger than that of indomethacin in 19-day-old and immature fetuses. In near-term fetuses, the constrictive effects of L-NAME were reduced, while indomethacin caused marked DA constriction. We conclude that endogenous NO may play a major role in regulating the patency of the DA in earlier fetal stages, while dilator prostaglandins may play a greater role in regulating the ductal patency in the near-term fetus.

Role of the nitric oxide-cGMP system in the regulation of ductus arteriosus patency in fetal rats

The purpose of this study was to examine the role of the nitric oxide (NO) and cyclic guanosine monophosphate (cGMP) system in the regulation of the ductus arteriosus (DA) patency in fetal rats. Pregnant rats were administered N(G)-nitro-L-arginine methyl ester (L-NAME, 50 mg/kg, ip), an NO synthase (NOS) inhibitor; methylene blue (30, 50 and 100 mg/kg, ip), a soluble guanylate cyclase inhibitor; or indomethacin (3 mg/kg, po), a cyclooxygenase inhibitor, at various times before cesarean section. Dams were decapitated to obtain the fetuses by cesarean section, and fetuses were rapidly frozen in an acetone-dry ice mixture. Using rapid freezing and shaving methods, the calibers of the DA, pulmonary artery (PA) and descending aorta (Ao) were measured to evaluate the effects of treatment. L-NAME reduced the DA calibers to 86% of the initial values, but recovery to the control levels occurred 6 hr after the injection. Indomethacin decreased the DA calibers to 34% of the control values and sustained the DA constriction until 24 hr after the treatment. Methylene blue caused DA constriction to almost the same degree as indomethacin, but the levels normalized within 24 hr after the treatment. We conclude that L-NAME caused a slight constriction of the DA, whereas methylene blue and indomethacin caused marked constriction of the vessels, suggesting that the NO-cGMP system as well as prostaglandins contribute to the DA patency.

Induction of major histocompatibility complex class II antigens on human colonic epithelium by interferon-gamma, tumor necrosis factor-alpha, and interleukin-2

Class II antigens are strongly expressed on the inflamed colonic epithelium in inflammatory bowel disease. However, the mechanism of this epithelial class II antigen induction is not fully understood. Increased activities of interferon (IFN)gamma, tumor necrosis factor (TNF)alpha, and interleukin (IL)2 have been shown in the inflamed mucosa of inflammatory bowel disease. Therefore, we studied whether these cytokines could induce class II antigens on the human colonic epithelium. By an organ culture technique, 284 normal colonic biopsy specimens obtained from 49 individuals were cultured in media containing different concentrations of cytokines with/without anti-IFNgamma R antibody. Colonic epithelial class II antigens were identified by the indirect immunoperoxidase staining method with anti-human leukocyte antigen (HLA)-DR, DP, and DQ monoclonal antibodies. IFNgamma, TNFalpha, and IL2 induced epithelial class II antigens in 16 of 16 cases (100%), 2 of 16 cases (12.5%), and 6 of 17 cases (35%), respectively. Epithelial class II antigen expression in response to TNFalpha was induced via IFNgamma but not via IL2. This is the first demonstration that: (i) the induction of class II antigens on the colonic epithelium in response to TNFalpha is mediated via IFNgamma, and (ii) that IL2 induces class II antigens.

Three cases of familial ulcerative colitis--in a mother and two of her sons

A pedigree of familial ulcerative colitis with their HLA haplotypes is reported. The mother and two children, the eldest and second of three sons were affected. The mother developed proctitis at age 35, and the lesion extended to the entire colon at the time of a relapse. The two sons developed ulcerative colitis in a similar fashion; total colitis, of moderate severity, developing at age 16 in both. The analysis of HLA haplotypes of all five family members suggested that the HLA responsible for ulcerative colitis in this family was not HLA B, C, or DR, but Aw24 and DQw1. The third son had the same HLA haplotype as the second son, and it was presumed that he would develop ulcerative colitis in the future. These cases, together with other cases of familial ulcerative colitis indicate that Aw24 and DQw1 are critical phenotypes for ulcerative colitis in Japan.

Pharmacokinetic analysis of the absorption enhancing action of decanoic acid and its derivatives in rats

The enhancing action of decanoic acid (C10) and its derivatives on mucosal absorption of phenolsulfonphthalein (PSP) in the jejunum or colon was analyzed using pharmacokinetics in rats. After administration of a solution containing PSP and an enhancer [C10, 2-hydroxydecanoic acid (2-OHC10), or 3-hydroxydecanoic acid (3-OHC10)] into the jejunal or colonic loop, the amounts of PSP and enhancer remaining in the loop and/or plasma PSP concentration were determined periodically. 2-OHC10 exhibited a greater absorption enhancing potency than C10, while 3-OHC10 was less effective. Disappearance of residual PSP from the loop ceased after complete absorption of the enhancer. The enhancer-induced disappearance rate constant of PSP correlated well with the product of the enhancer disappearance rate and its capacity to sequester calcium ions. In conclusion, the enhancement of PSP mucosal absorption by C10 and its derivatives is consistent with a pharmacokinetic model, assuming that the enhanced membrane permeability of PSP depends on the enhancer disappearance kinetics from the loop and its calcium ion sequestration capacity.

[The sub-classification of pre-proliferative diabetic retinopathy]

The authors divided 155 eyes (106 cases) affected by pre-proliferative diabetic retinopathy into three sub-groups according to the severity of retinopathy and followed them for one year. The criteria for and numbers of eyes in each group were as follows; 1) mild type with soft exudate and without apparent non-perfused areas on fluorescein angiography (39 eyes). 2) moderate type with soft exudate and demonstrable non-perfused areas (103 eyes). 3) severe type with soft exudates, non-perfused areas and venous beading (13 eyes). The proportion undergoing photocoagulation was 23% in the mild type, 81% in the moderate type and 100% in the severe type. None of the eyes in the mild type underwent photocoagulation unless they advanced to a more severe type. Nine eyes of the mild type which progressed to moderate type during the follow-up period underwent focal photocoagulation. Panretinal photocoagulation was performed in 29% of moderate type eyes and 77% of severe type eyes. The courses of these three sub-groups were analyzed after one year of follow up. The proportion developing proliferative retinopathy was 0% in mild type, 17% in moderate type and 46% in severe type. Based on the above results, we conclude that the sub-classification we propose in this paper can be applied in managing patients with pre-proliferative diabetic retinopathy.

[Clinical study of venous abnormalities in diabetic retinopathy]

The authors studied 304 eyes (248 cases) affected by diabetic retinopathy in relation to venous abnormalities by ophthalmoscopy, slit lamp examination with contact lens and fluorescein angiography. The posterior pole and surrounding mid-peripheral area were examined. The subjects consisted of 225 eyes with pre-proliferative and 79 eyes with proliferative retinopathy. Fifty-six eyes (18%) had venous abnormalities: 17 of the 225 eyes (8%) with pre-proliferative retinopathy and 39 of the 79 eyes (49%) with proliferative retinopathy. In the 56 eyes with venous abnormalities. 39 (96%) showed beading. 14 (25%) showed looping and 2 (4%) showed duplication. All eyes which showed looping or duplication had proliferative retinopathy. The locations of the venous abnormalities were analyzed: 42% were in secondary branches, 27% in tertiary branches, 18% in primary branches, 10% in fourth branches and 3% in fifth branches. The portion of the fundus affected was upper temporal, lower temporal, upper nasal and lower nasal in 28%, 22%, 29% and 21%, respectively. Based on our results, eyes with looping or duplication on ophthalmoscopic or slit lamp examination, have an extremely high probability of being in some stage of proliferative retinopathy. Retinopathy should be confirmed by fluorescein angiography and photocoagulation should be performed as quickly as possible.

The risk of cerebral infarction in non-valvular atrial fibrillation: effects of age, hypertension and antihypertensive treatment

The stroke risk was studied on 600 subjects with nonvalvular atrial fibrillation (NVAF) compared with the general population. The age-matched relative risk of stroke was highest in the 41- to 50-year-old population (12.6) but decreased with age (8.2 for 51-60 years, 3.6 for 61-70 years, and 2.6 for 71-80 years) owing to the increase in stroke incidence with age in the general population. There was no particularly vulnerable period for stroke from NVAF diagnosis until the 15the year. Stroke incidence was greater in hypertensives than in normotensives, but was not different between treated and untreated subjects among hypertensives.

[Impairment of erythrocyte anti-oxidant defense mechanisms in hypoxemic patients]

Defense mechanisms against lipid peroxidation were studied in erythrocytes from hypoxemic patients. The levels of lipid peroxides in patients erythrocytes were higher than those of control subjects (15.3 +/- 10.9 vs 7.5 +/- 3.0, p less than 0.05). The levels of reduced glutathione (GSH) decreased in erythrocytes from the patients (426 +/- 108 vs 756 +/- 201, p less than 0.01). Activities of glutathione peroxidase (GPX) and superoxide dismutase (SOD) were lower than those of control subjects (GPX; 27.6 +/- 7.1 vs 35.1 +/- 3.8, SOD; 76.6 +/- 42.9 vs 125.7 +/- 40.1, p less than 0.01). Positive correlations were observed between the levels of arterial oxygen pressures (PaO2) and the GSH concentrations, the activities of GPX and SOD, respectively. These data suggest that decreased anti-oxidant activity enhances lipid peroxidation in erythrocytes from hypoxemic patients.