Respiratory microbiome profiles are associated with distinct inflammatory phenotype and lung function in children with asthma

BACKGROUND

Respiratory microbiome studies have fostered our understanding of various phenotypes and endotypes of heterogeneous asthma. However, the relationship between the respiratory microbiome and clinical phenotypes in children with asthma remains unclear. We aimed to identify microbiome-driven clusters reflecting the clinical features of asthma and their dominant microbiotas in children with asthma.

METHODS

Induced sputum was collected from children with asthma, and microbiome profiles were generated via sequencing of the V3-V4 region of the 16S rRNA gene. Cluster analysis was performed using the partitioning around medoid clustering method. The dominant microbiota in each cluster was determined using the Linear Discriminant Effect Size analysis. Each cluster was analyzed for association among the dominant microbiota, clinical phenotype, and inflammatory cytokine.

RESULTS

Eighty-three children diagnosed with asthma were evaluated. Among four clusters reflecting the clinical characteristics of asthma, cluster 1, dominated by Haemophilus and Neisseria, demonstrated lower post-bronchodilator (BD) forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC) than that in the other clusters and more mixed granulocytic asthma. Neisseria negatively correlated with pre-BD and post-BD FEV1/FVC. Haemophilus and Neisseria positively correlated with programmed death-ligand (PD-L)1.

CONCLUSION

To our knowledge, this study is the first to analyze the relationship between an unbiased microbiome-driven cluster and clinical phenotype in children with asthma. The cluster dominated by Haemophilus and Neisseria showed fixed airflow obstruction and mixed granulocytic asthma, which correlated with PD-L1 levels. Thus, microbiome-driven unbiased clustering can help identify new asthma phenotypes related to endotypes in childhood asthma.

Short communication: Dietary bovine milk-derived exosomes improve bone health in an osteoporosis-induced mouse model

Osteoporosis is a systemic skeletal disease characterized by low bone mass and micro-architectural deterioration of bone tissue, with a consequent increase in bone fragility and fracture susceptibility. In an aged society with increased life expectancy, the incidence rate of osteoporosis is also rapidly increasing. Inadequate nutrition may negatively influence bone metabolism. Recently, many studies have investigated the functionality of milk-derived exosomes, which play important roles in cell-to-cell communication. However, there are few reports of how milk-derived exosomes influence osteoblast proliferation and differentiation. Here, we determined whether bovine colostrum-derived exosomes promote anti-osteoporosis in vitro and in vivo. Tartrate-resistant acid phosphatase-stained cells were significantly inhibited in Raw264.7 cells treated with exosomes, indicating reduced osteoclast differentiation. We induced osteoporosis in mice using glucocorticoid pellets after orally administering exosomes for 2 mo. Interestingly, the bone mineral density of exosome-fed mouse groups was significantly improved compared with the glucocorticoid-induced osteoporosis group without exosome treatment. In addition, Lactobacillus were decreased in the gut microbiota community of osteoporosis-induced mice, but the gut microbiota community composition was effectively restored by exosome intake. Taken together, we propose that exosomes isolated from bovine colostrum could be a potential candidate for osteoporosis prevention, bone remodeling improvement, and inhibition of bone resorption. To our knowledge, this is the first time that a protective effect of milk exosomes against osteoporosis has been demonstrated in vivo. Our results strongly suggest that bovine colostrum exosomes might be used as a prophylaxis to prevent the onset of osteoporosis. Indeed, our results offer promising alternative strategies in the nutritional management of age-related bone complications.

Identification of atopic dermatitis phenotypes with good responses to probiotics (Lactobacillus plantarum CJLP133) in children

The therapeutic effect of probiotics in atopic dermatitis (AD) remains controversial and varies according to the individual patient. We aimed to identify a population of AD patients with a good clinical response to probiotic treatment. We recruited 76 children with a median age of 7.1 years who suffered from moderate to severe AD. After a 2-week washout period, all patients were given Lactobacillus plantarum CJLP133 at a dosage of 1×10¹⁰ colony-forming units once a day for 12 weeks. We measured eosinophil counts in the peripheral blood, the proportion of CD4⁺CD25⁺Foxp3⁺ regulatory T (Treg) cells in CD4⁺ T cells, serum total immunoglobulin E (IgE) levels, and specific IgE against common allergens before the start of the treatment (T1) and at discontinuation (T2). Responders were defined as patients with at least a 30% reduction in the SCORing of AD (SCORAD) index after treatment. There were 36 responders and 40 non-responders after probiotic treatment. The median SCORAD was reduced from 29.5 (range 20.6-46.3) at T1 to 16.4 (range 6.3-30.8) at T2 in the responder group (P<0.001). In multivariable logistic regression analysis, a good clinical response was significantly associated with high total IgE levels (aOR 5.1, 95% CI 1.1-23.6), increased expression of transforming growth factor (TGF)-β (aOR 4.6, 95% CI 1.3-15.9), and a high proportion of Treg cells in CD4⁺ T cells (aOR 3.7, 95% CI 1.1-12.7) at T1. In the responder group, the proportion of Treg cells was significantly increased after 12 weeks of treatment (P=0.004), while TGF-β mRNA expression was decreased (P=0.017). Our results suggest that a subgroup of patients with a specific AD phenotype showing an immunologically active state (high total IgE, increased expression of TGF-β, high numbers of Treg cells) may benefit from probiotic treatment with L. plantarum CJLP133.

Influences of somatic donor cell sex on in vitro and in vivo embryo development following somatic cell nuclear transfer in pigs

Objective

The present study investigates pre- and post-implantation developmental competence of nuclear-transferred porcine embryos derived from male and female fetal fibroblasts.

Methods

Male and female fetal fibroblasts were transferred to in vitro-matured enucleated oocytes and in vitro and in vivo developmental competence of reconstructed embryos was investigated. And, a total of 6,789 female fibroblast nuclear-transferred embryos were surgically transferred into 41 surrogate gilts and 4,746 male fibroblast nuclear-transferred embryos were surgically transferred into 25 surrogate gilts.

Results

The competence to develop into blastocysts was not significantly different between the sexes. The mean cell number of female and male cloned blastocysts obtained by in vivo culture (143.8±10.5 to 159.2±14.8) was higher than that of in vitro culture of somatic cell nuclear transfer (SCNT) groups (31.4±8.3 to 33.4±11.1). After embryo transfer, 5 pregnant gilts from each treatment delivered 15 female and 22 male piglets. The average birth weight of the cloned piglets, gestation length, and the postnatal survival rates were not significantly different (p<0.05) between sexes.

Conclusion

The present study found that the sex difference of the nuclear donor does not affect the developmental rate of porcine SCNT embryos. Furthermore, postnatal survivability of the cloned piglets was not affected by the sex of the donor cell.

Short communication: In vivo screening platform for bacteriocins using Caenorhabditis elegans to control mastitis-causing pathogens

This study aimed to develop an in vivo screening platform using Caenorhabditis elegans to identify a novel bacteriocin for controlling the mastitis-causing pathogen Staphylococcus aureus strain RF122 in dairy cows. Using Bacillus spp. isolated from traditional Korean foods, we developed a direct in vivo screening platform that uses 96-well plates and fluorescence image analysis. We identified a novel bacteriocin produced by Bacillus licheniformis strain 146 (lichenicin 146) with a high in vivo antimicrobial activity using our liquid C. elegans-Staph. aureus assay. We also determined the characteristics of lichenicin 146 using liquid chromatography-mass spectrometry and confirmed that it shared homologous sequences with bacteriocin family proteins. In addition, RNA-sequencing analysis revealed genes encoding cell surface or membrane proteins (SAB0993c, SAB0150, SAB0994c, and SAB2375c) that are involved in the bactericidal activity of lichenicin 146 against Staph. aureus strain RF122 infection as well as those encoding transcriptional regulators (SAB0844c and SAB0133). Thus, our direct in vivo screening platform facilitates simple, convenient, cost-effective, and reliable screening of potential antimicrobial compounds with applications in the dairy field.

Short communication: Development of a direct in vivo screening model to identify potential probiotic bacteria using Caenorhabditis elegans

Caenorhabditis elegans is an accepted model host to study host-bacteria interactions in the gut, in addition to being a simple model with which to study conserved aspects of biological signaling pathways in intestinal environments, because these nematode worms have similar intestinal cells to those of humans. Here, we used C. elegans to develop a new in vivo screening system for potential probiotic lactic acid bacteria (LAB). Initially, critical colonization ability of LAB strains isolated from Korean infant feces was screened in the worm intestinal tract over a period of 5 d. Furthermore, we investigated host health-promoting activities, including longevity-extending effects and immune-enhancing activities against foodborne pathogen infection. We identified 4 LAB strains that were highly persistent in the nematode gut and that significantly prolonged the longevity of C. elegans and improved the survival of C. elegans in response to infection by Staphylococcus aureus. The 4 LAB strains we identified showed resistance to acid and bile conditions, assimilated cholesterol, and were able to attach to a mucus layer. The 4 LAB isolates were identified as Lactobacillus plantarum using 16S rRNA sequencing analysis. Taken together, we developed a direct in vivo screening system using C. elegans to study host health-promoting LAB. Our system is simple, rapid, cost-effective, and reliable, and we anticipate that this system will result in the discovery of many more potential probiotic bacteria for dairy foods.

Uncertain areas in the diagnosis of allergic bronchopulmonary aspergillosis in patients with asthma

BACKGROUND AND OBJECTIVE

The prevalence of allergic bronchopulmonary aspergillosis (ABPA) in patients with bronchial asthma remains unknown. We evaluated the roles of various laboratory tests in the diagnosis of ABPA, including, skin prick test (SPT) for Aspergillus fumigatus (Af), and serum Af specific IgE and IgG antibody measurement.

METHODS

A total of 50 asthma patients with more than 1000cell/μL of peripheral blood eosinophils were prospectively collected between January 2007 and September 2011. Evaluations using SPT for Af, serum total IgE and specific IgE antibody to Af by CAP system, IgG antibody to Af by enzyme immunoassay (EIA) or CAP system were performed according to the essential minimal criteria for the diagnosis of ABPA - asthma, immediate cutaneous reactivity to Af, elevated total IgE, and raised Af specific IgE and IgG.

RESULTS

Among 50 patients, three patients (6.0%) were diagnosed as ABPA, of whom each confirmed five items of the essential minimal diagnostic criteria for the diagnosis of ABPA. Six patients (12.0%) showed negative responses to Af in SPT, but positive responses in specific IgE by CAP system. Eight patients (16.0%) showed negative responses to IgG to Af by CAP system, but positive responses by enzyme immunoassay (EIA).

CONCLUSIONS

SPT and serum IgE to Af measurement by CAP system should be performed simultaneously. It is reasonable to set up cut-off values in Af specific IgE/IgG by CAP system for the differentiation of ABPA from Af sensitised asthma patients.

A Whole Genome Association Study on Meat Quality Traits Using High Density SNP Chips in a Cross between Korean Native Pig and Landrace

A whole genome association (WGA) study was performed to detect significant polymorphisms for meat quality traits in an F₂ cross population (N = 478) that were generated with Korean native pig sires and Landrace dams in National Livestock Research Institute, Songwhan, Korea. The animals were genotyped using Illumina porcine 60k SNP beadchips, in which a set of 46,865 SNPs were available for the WGA analyses on ten carcass quality traits; live weight, crude protein, crude lipids, crude ash, water holding capacity, drip loss, shear force, CIE L, CIE a and CIE b. Phenotypes were regressed on additive and dominance effects for each SNP using a simple linear regression model, after adjusting for sex, sire and slaughter stage as fixed effects. With the significant SNPs for each trait (p<0.001), a stepwise regression procedure was applied to determine the best set of SNPs with the additive and/or dominance effects. A total of 106 SNPs, or quantitative trait loci (QTL) were detected, and about 32 to 66% of the total phenotypic variation was explained by the significant SNPs for each trait. The QTL were identified in most porcine chromosomes (SSCs), in which majority of the QTL were detected in SSCs 1, 2, 12, 13, 14 and 16. Several QTL clusters were identified on SSCs 12, 16 and 17, and a cluster of QTL influencing crude protein, crude lipid, drip loss, shear force, CIE a and CIE b were located between 20 and 29 Mb of SSC12. A pleiotropic QTL for drip loss, CIE L and CIE b was also detected on SSC16. These QTL need to be validated in commercial pig populations for genetic improvement in meat quality via marker-assisted selection.

Preventive effect of fermented Maillard reaction products from milk proteins in cardiovascular health

The aim of this study was to determine the dual effect of Maillard reaction and fermentation on the preventive cardiovascular effects of milk proteins. Maillard reaction products (MRP) were prepared from the reaction between milk proteins, such as whey protein concentrates (WPC) and sodium caseinate (SC), and lactose. The hydrolysates of MRP were obtained from fermentation by lactic acid bacteria (LAB; i.e., Lactobacillus gasseri H10, L. gasseri H11, Lactobacillus fermentum H4, and L. fermentum H9, where human-isolated strains were designated H1 to H15), which had excellent proteolytic and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities (>20%). The antioxidant activity of MRP was greater than that of intact proteins in assays of the reaction with 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt and trivalent ferric ions; moreover, the effect of MRP was synergistically improved by fermentation. The Maillard reaction dramatically increased the level of antithrombotic activity and 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR) inhibitory effect of milk proteins, but did not change the level of activity for micellar cholesterol solubility. Furthermore, specific biological properties were enhanced by fermentation. Lactobacillus gasseri H11 demonstrated the greatest activity for thrombin and HMGR inhibition in Maillard-reacted WPC, by 42 and 33%, respectively, whereas hydrolysates of Maillard-reacted SC fermented by L. fermentum H9 demonstrated the highest reduction rate for micellar cholesterol solubility, at 52%. In addition, the small compounds that were likely released by fermentation of MRP were identified by size-exclusion chromatography. Therefore, MRP and hydrolysates of fermented MRP could be used to reduce cardiovascular risks.

The effects of artificial activation timing on the development of SCNT-derived embryos and newborn piglets

This study investigated the effects of two different activation regimens on the developmental potential of somatic cell nuclear transfer (SCNT) embryos and postnatal survivability of the cloned piglets. In vitro matured oocytes were enucleated and reconstructed with porcine fetal fibroblasts. On the basis of the activation regimen used, the reconstructed porcine embryos were allocated into two groups: Group 1-simultaneous electrical pulses and activation group (SFA group); and Group 2-electrical fusion without calcium followed by electrical pulses with calcium after colcemid and cytochalasin B treatment for 5h (DA group). Embryonic development in both SFA and DA groups was determined at day 6 of culture in NSCU-23 medium. To investigate the post-implantation development after the two activation methods, embryos were cultured for 1 day and then transferred into the oviducts of estrus-synchronized recipients. DA group had significantly (p<0.05) higher cleavage rates than SFA group. However, the developmental rate to the blastocyst stage and the mean cell number of blastocysts did not differ (p>0.05) between SFA and DA groups. Moreover, the pregnancy rate of SFA group was not significantly different compared to DA group. A total of 20 cloned piglets (SFA group-8 live piglets, DA group-11 live piglets and one stillborn) were obtained in the present study. The birth weight of the cloned piglets (live births) did not differ (p>0.05) between the two groups. Furthermore, no difference was observed in the postnatal survival rates of the cloned piglets obtained using two different activation regimens. These results suggest that the timing of artificial activation and additional chemical treatments do not affect the developmental rate of porcine SCNT embryos. Remarkably, the pregnancy rate and postnatal survivability of the cloned piglets did not vary between SFA and DA groups.

Electrical activation enhances pre-implantation embryo development following sperm injection into in vitro matured pig oocytes

The objective of this study was to evaluate the effect of electrical stimulation (EST) on pronuclear formation, chromosomal constitution, and developmental capability among in vitro matured pig oocytes following intracytoplasmic sperm injection (ICSI). After ICSI, the oocytes were randomly distributed and cultured into 3 groups: the EST activated ICSI group, non-activation ICSI group, and in vitro fertilization (IVF) group. The proportion of oocytes in which 2 pronuclei were formed in ICSI groups was significantly higher in the former groups than in the IVF group (96.2 and 93.5 vs. 64.5%, respectively, P<0.05). The cleavage rate was significantly higher in EST activated ICSI group (78.6%) than in the IVF and non-activated ICSI groups (51.8 and 46.0%, respectively, P<0.05), as was the proportion of oocytes that developed to the blastocyst stage at day 7 (18.9 vs. 11.6 and 9.1%, respectively, P<0.05). Diploid blastocysts were observed in 52.4, 63.0, and 65.2% of oocytes in the IVF, activated, and non-activated ICSI groups, respectively. Eight out of 23 gilts (34.8%) were confirmed to be pregnant in activated ICSI groups, but none of these pregnancies were carried to term. These results show that oocyte activation after ICSI is effective in elevating the cleavage rate and blastocyst development, while ensuring normal chromosome composition. Further research is needed to determine the pregnancy maintenance requirements for ICSI-embryos in pigs.

Histone deacetylase inhibition improves activation of ribosomal RNA genes and embryonic nucleolar reprogramming in cloned mouse embryos

Our group found that the treatment of embryos with histone deacetylase inhibitors (HDACi), including trichostatin A, Scriptaid, suberoylanilide hydroxamic acid, and oxamflatin, after cloning by somatic cell nuclear transfer (SCNT) resulted in significantly improved efficiency. Although many researchers have investigated the use of HDACi treatment to improve the quality of cloned mouse embryos, the mechanism underlying this treatment has not been completely understood. We believe that the effect of HDACi on embryonic gene activation (EGA) is important for normal development of cloned embryos. In the present study, using highly sensitive fluorescence in situ hybridization (FISH) with probes complementary to mouse rDNA, the effect of Scriptaid on the onset of rRNA synthesis was examined in cloned embryos. In addition, to determine how Scriptaid affects pre-rRNA processing machinery in SCNT embryos with activated rDNA transcription, functional nucleolar formation was analyzed in detail by combined assessment of rRNA synthesis and nucleolar protein allocation in preimplantation embryos. In this experiment, at least part of the rRNA localization by FISH was substituted by 5-bromouridine 5'-triphosphate staining after alpha-amanitin treatment. The results show that in the late 2-cell stage, a number of SCNT embryos initiated transcriptional activation while having one blastomere showing inactivated rRNA transcription and another blastomere showing activated rRNA transcription and despite both nuclei being in interphase. In addition, in some SCNT embryos, the same nuclei contained a mixture of inactively and actively transcribed rRNA, which was rarely observed in intracytoplasmic sperm injection embryos. This asynchronous transcription induced a delay of one cell cycle in SCNT embryo activation of functional nucleoli. Scriptaid can overcome this failure in the timely onset of embryonic gene transcription by activation of rRNA genes and promotion of nucleolar protein allocation during the early phase of EGA.

Developmental arrest of scNT-derived fetuses by disruption of the developing endometrial gland as a result of impaired trophoblast migration and invasiveness

Somatic cell nuclear transfer (scNT)-derived pig placenta tissues of gestational day 30 displayed avascularization and hypovascularization. Most of the cytotrophoblast-like cells of the developing scNT-derived placenta villi were improperly localized or exhibited impaired migration to their targeting loci. Id-2, Met, MMP-9, and MCM-7 were barely detectable in the cytotrophoblast cells of the scNT-derived placenta villi. Active MMP-2 and MMP-9 expression was significantly down-regulated in the scNT-embryo transferred recipient uteri. scNT clones exhibited a hypermethylated pattern within the pig MMP-9 promoter region and the significance of GC box in the regulation of MMP-9 promoter activity. Marked apoptosis was observed in the developing endometrial gland of scNT-embryo transferred recipient uteri. Collectively, our data strongly indicated that early gestational death of scNT clones is caused, at least in part, by disruption of the developing endometrial gland as a result of impaired trophoblast migration and invasiveness due to the down-regulation of active MMP-9 expression.

Osmolarity at early culture stage affects development and expression of apoptosis related genes (Bax-alpha and Bcl-xl) in pre-implantation porcine NT embryos

This study examined whether high osmolarity of culture medium at the early culture stage affects development and expression of apoptosis related genes (Bax-alpha and Bcl-xl) of porcine nuclear transfer (NT) and in vitro fertilization (IVF) embryos. NT and IVF embryos were divided into three groups and the basic medium was PZM-3 (260-270 mOsmol, control group). The control group of embryos was cultured in PZM-3 for whole culture period. Other two groups of embryos were cultured in a modified PZM-3 with 0.05 M sucrose (300-320 mOsmol, sucrose group) or increased NaCl to 138 mM (300-320 mOsmol, NaCl group) for the first 2 days, and then cultured in PZM-3 for 4 days. NT embryos cultured in NaCl group showed a significantly higher developmental rate to the blastocyst stage with a decreased apoptosis rate compared to the control (P < 0.05). There was no difference in blastocyst formation and apoptosis incidence among the three culture treatments for IVF-derived embryos. Bax-alpha mRNA expression was significantly higher in the control than sucrose or NaCl group for both NT and IVF embryos (P < 0.05). Moreover, the relative abundance of Bax-alpha/Bcl-xl was higher in the control than the treatment groups. These results indicate that the higher osmolarity at the early embryonic stage of porcine NT and IVF embryos can improve the in vitro development with reduced apoptosis through regulating the Bax-alpha/Bcl-xl gene expression.

Treatment of non-biodegradable cutting oil wastewater by ultrasonication-Fenton oxidation process

To treat cutting oil wastewater produced in metal surface treatment industry, Ultrasonication (US)-Fenton process, which is one of the advanced oxidation processes, was used. The optimum conditions to treat non-biodegradable pollutants using the US-Fenton process were that the application rates of H2O2 and FeSO4 were 10% and 3 g/L, respectively, the value of pH was 3, and the ultrasonication time was 30 min. It identified non-degradable pollutants such as ethylene diamine tetraacetic acid (EDTA) and Triethanolamine (TEA) in the cutting oil wastewater. TLC analysis of two compounds of treated water by the coagulation process was similar to that of raw water. However, TLC analysis of two compounds of US-Fenton process was different from that of raw water, meaning that US-Fenton process decomposed the EDTA and TEA. To study the possibility of application with the US-Fenton process to pilot plant, the pollutants treatment efficiency of three different methods, such as US-Fenton process, activated sludge process and coagulation process, in continuous experiments were compared. The removal rate of pollutants by the US-Fenton process according to the effluent time was higher than any other processes. The removal rates of COD, SS, T-N and T-P by US-Fenton process were 98, 93, 75 and 95%, respectively.

A rare and often unrecognized cerebromeningitis and hemodynamic disorder: a major cause of sudden death in somatic cell cloned piglets

In this study, we generated 40 somatic cell cloned (scNT) piglets. Of these, five piglets were stillborn, 22 scNT piglets died suddenly within the first week of life, and 1 piglet died after 40 days. Twelve scNT piglets are still healthy. The birth weights of compromised scNT piglets in comparison with those of normal scNT piglets are significantly reduced (0.80 +/- 0.29 vs 1.27 +/- 0.30 kg, p < 0.05), in spite of longer gestation (114 versus 120 day). Significant findings from histological examinations showed that approximately 25% (7/28) of scNT piglets showed severe congestion of lung and liver or neutrophilic inflammation in brain indicating that unexpected phenotypes can appear as a result of somatic cell cloning. Two-dimensional gel electrophoresis experiments revealed changes in the responses of several detoxification-related proteins related to stress and inflammation and found significant alterations in myocardium-specific proteins, indicating hemodynamic disorder. scNT piglets that survived to adulthood did not show any abnormality except skin and hair color depigmentation. The present study suggests that cerebromeningitis and hemodynamic disorder are a major risk factor for sudden early death of scNT piglets. Although we cannot completely exclude the possibility that scNT piglets are susceptible to specific respiratory infections, our data suggests that the early death of scNT clones is due to cardiopulmonary functional abnormalities and cerebromeningitis.

Detection of rare Leydig cell hypoplasia in somatic cell cloned male piglets

In this investigation, 22 cloned male piglets were obtained by male fetal fibroblast-cell-derived nuclear transfer. Eighteen of the cloned animals died. The two cell lines did not differ significantly with regard to efficiency of live piglet production. The gross anatomy of the testes of male piglets that died was normal. However, one piglet displayed Leydig cell hypoplasia (LCH). No anatomical defects were detected in the testes of other cloned male piglets. TUNEL analysis of the testis with LCH revealed significant apoptosis in the Leydig cells, while apoptosis was rarely detected in Sertoli cells and spermatogonia. In contrast, testes from the remaining 17 piglets that died appeared normal in size, and their Sertoli and Leydig cell numbers were comparable to those in control piglet testes. Although cloned piglets were derived from fibroblasts obtained from the same fetus, phenotypic instability between cells used for the production of somatic cell cloned piglets suggests that abnormalities in male cloned piglets are caused not by technical problems and/or reprogramming effects, but rather by epigenetically and/or genetically damaged cell-specific effects.

Tissue specific and inducible expression of resveratrol synthase gene in peanut plants

The expression of resveratrol synthase (RS) genes is induced by biotic and abiotic factors in peanut cell cultures. However, little is known about the regulation of the RS gene expression in peanut plants. The expression of RS genes was investigated in peanut plants with a peanut RS clone, pPRS3C, which encodes two polypeptides that show about a 96% amino acid sequence identity to peanut RS2 and RS3, respectively. A low level of RS mRNA was detected in the roots of peanut plants grown aseptically in vitro. In mature peanut plants that were grown in the field, however, RS mRNAs were present at relatively high levels in both the roots and pods, but at below the detection limit in leaves. RS mRNAs were abundant in young pods and decreased dramatically in mature pods. The RS mRNA expression was induced by yeast extract and UV in leaves and roots, and also by wounding in leaves. Stress hormones, such as ethylene, jasmonic acid, and salicylic acid, induced RS mRNA accumulation in leaves. These results indicate that the RS gene expression is induced by biotic and abiotic stresses through the stress hormones in peanut plants. The induction of the RS gene expression by biotic and abiotic stresses could provide peanut plants with protection from microbial infections through resveratrol synthesis. The RS gene expression in developing pods has significant implications in terms of the role of resveratrol as a phytochemical for human health.

Increased angiogenesis and Fas-ligand expression are independent processes in acute myeloid leukemia

We evaluated the clinical significance of tumor angiogenesis and Fas-ligand (FasL) expression using parameters including the microvessel count (MVC), vascular endothelial growth factor (VEGF) level, and FasL expression in patients with acute myeloid leukemia (AML). Paraffin-embedded bone marrow (BM) sections from 43 AML patients at diagnosis, 20 patients after subsequent induction therapy, and 18 controls with non-invasive lymphoma were stained immunohistochemically for von Willebrand factor (vWF) and FasL. VEGF in BM mononuclear cells from 32 AML patients at diagnosis and 10 controls, including bone marrow transplantation donors, was assayed by an ELISA method. We found that the mean MVC, VEGF level, and FasL expression in AML patients at diagnosis were significantly higher than those of controls, with a significant correlation between the MVC and VEGF levels (r=0.43). However, there were no correlations between FasL expression and MVC or VEGF level. The mean MVC and FasL expression after induction therapy were lower than those evaluated at diagnosis, but were higher than those of controls. There was a correlation between the MVC and percentage of BM blasts (r=0.479), but no correlation between the MVC, VEGF level, or FasL expression and other hematologic or clinical variables. Our findings provide evidence of increased angiogenesis and tumor immune escape in AML, and both angiogenesis and tumor immune escape are independent processes in AML.

Secondary myeloid/natural killer cell acute leukemia following T-cell lymphoma

A 56-year-old woman was treated with combination chemotherapy and radiation therapy for peripheral T-cell lymphoma. Following complete remission for a period of 6 months, she returned again with marked leukocytosis. Leukemic cells were characterized by scanty cytoplasm with fine azurophilic granules, and were highly positive for myeloperoxidase and sudan black-B. Immunophenotypic analysis revealed that blast cells were positive for myeloid antigens (CD13, CD33), and natural killer (NK) cell antigen (CD56), but negative for T-cell antigens (CD2, CD5, CD7), B-cell antigens (CD19, CD20), CD34, and HLA-DR. The case was diagnosed as secondary myeloid/NK cell acute leukemia following non-Hodgkin's lymphoma. Despite aggressive chemotherapy against leukemia, she died of multiorgan failure 7 months following onset of leukemia. We present, to the best of our knowledge, the first published report of what seems to be a secondary myeloid/NK cell acute leukemia following T-cell lymphoma.

Telomere length changes in patients with aplastic anaemia

To investigate telomere changes in patients with aplastic anaemia (AA) and clinical factors influencing the telomere dynamics, telomere length (TL) was measured in peripheral blood mononuclear cells using Southern blot analysis of 42 patients with AA and 39 healthy normal controls. Nineteen patients received supportive treatment only, while the remaining 23 patients received immunosuppressive therapy with anti-thymocyte globulin or anti-lymphocyte globulin +/- cyclosporin A. In AA patients, TL was on average 1.41 kb shorter than that of age-matched normal controls (P < 0.001). In patients treated with immunosuppression, the mean TL of non-responders was significantly shorter than that of age-matched normal controls (P < 0.001), while no difference in TL was detected in responders compared with controls. Positive correlation was observed between the extent of telomere shortening, the severity of neutropenia (P = 0.05) and the degree of mean corpuscular volume elevation (P = 0.005) at the time of the study. However, there was no correlation with time elapsed since diagnosis (P = 0.214). These findings suggest that haematopoietic stem cells in patients with AA rapidly lose TL at the onset of the disease. The TL shortening may reflect the severity of impairment of haematopoiesis.

Clinical efficacy of granulocyte transfusion therapy in patients with neutropenia-related infections

Granulocyte transfusions have been advocated by some for the treatment of severe, progressive infections in neutropenic patients who fail to respond to antimicrobial agents and recombinant hematopoietic growth factors. We conducted the current study to determine an appropriate method of granulocyte mobilization in healthy donors, and to evaluate the safety and efficacy of granulocyte transfusion therapy in patients with neutropenia-related infections. To mobilize granulocytes (n=55), healthy normal donors were stimulated in one of the following ways: (1) dexamethasone, 3 mg/m2 intravenously 15 min prior to leukapheresis (n = 5); (2) granulocyte colony-stimulating factor (G-CSF), 5 microg/kg subcutaneously 12 to 14 h prior to collection (n=37); or (3) G-CSF and dexamethasone (n= 13). The mean granulocyte yield from stimulation with G-CSF plus dexamethasone was significantly higher than from stimulation with dexamethasone or G-CSF alone. Twenty-five patients with severe neutropenia-related infections unresponsive to appropriate antimicrobial agents received a total of 55 granulocyte transfusions. The patients from whom fungi or Gram-negative organisms were isolated showed a more favorable response than those infected with Gram-positive organisms. However, the responses to the granulocyte transfusion therapy could not be correlated with the transfused dose, mobilization agents, or the 1 h or 24 h post-transfusion absolute neutrophil counts. We conclude that granulocyte transfusion therapy may be clinically useful for neutropenia-related infections by fungi or Gram-negative organisms.

Acquired hemophilia successfully treated with oral immunosuppressive therapy

Acquired hemophilia is a rare disorder associated with serious bleeding in nonhemophilic patients. We had a 40-year-old woman who was diagnosed as acquired hemophilia with a factor VIII inhibitor level of 27.5 BU/mL. She was presented with gross hematuria and severe right shoulder pain, and was successfully treated with daily oral cyclophosphamide and prednisone for 2 weeks. After the remission, the doses of prednisone and cyclophosphamide were slowly decreased and she remained in complete remission without further bleeding episodes.

Ruptured Klebsiella pneumoniae liver abscess after high-dose cyclophosphamide for severe aplastic anemia

A 19-year-old woman with severe aplastic anemia who had previously failed antithymocyte globulin/cyclosporine A received high-dose cyclophosphamide without bone marrow rescue. On day +14, she complained of right upper quadrant abdominal pain and fever. A CT scan of the abdomen showed multiple liver abscesses with rupture and Klebsiella pneumoniae was isolated from blood. In spite of aggressive antibiotic therapy, she rapidly deteriorated and died of overwhelming sepsis. To our knowledge, our patient is the first case of fatal ruptured liver abscess after high-dose cyclophosphamide in a patient with severe aplastic anemia.

A randomized comparison of oral and intravaginal misoprostol for labor induction

OBJECTIVE

To compare oral misoprostol (100 microgram) to vaginal misoprostol (25 microgram) for cervical ripening and labor induction.

METHODS

Two hundred thirty-six women with medical or obstetric indications for labor induction and undilated, uneffaced cervices were assigned randomly to receive 100 microgram of oral or 25 microgram of vaginal misoprostol every 4 hours for 24 hours. Intravenous oxytocin was then given using a standardized protocol. We anticipated that 31% of women treated orally and 50% of women treated vaginally would deliver vaginally within 24 hours of starting labor induction.

RESULTS

Among 234 subjects, 121 received oral and 113 received vaginal misoprostol. The mean (+/- standard deviation [SD]) interval from start of induction to delivery was 1240 +/- 845 minutes for orally treated women and 1381 +/- 802 minutes for vaginally treated women (P =.06, log-transformed data). More orally treated women delivered vaginally in 24 hours than vaginally treated women (74 versus 54, P =.14, relative risk [RR] 1.14, 95% confidence interval [CI] 0.92, 1.40). One hundred six women (87.6%) who received oral misoprostol delivered vaginally, compared with 88 women (77.9%) who received vaginal misoprostol (P =.07). Oxytocin was given to 60 (49. 6%) orally treated and 59 (52.2%) vaginally treated subjects (P =. 69). More women in the oral group had tachysystole, nine compared with two (P =.06), hypertonus, and hyperstimulation. Frequencies of intrapartum complications and birth outcomes were similar between groups.

CONCLUSION

Oral misoprostol 100 microgram and vaginal misoprostol 25 microgram were similarly effective for cervical ripening and labor induction. Oral administration was associated with trends toward higher likelihood of vaginal delivery and more uterine tachysystole.

Hepatosplenic B-cell lymphoma associated with hemophagocytic syndrome: a case report

While T-cell non-Hodgkin's lymphoma (NHL) associated with hemophagocytic syndrome (HPS) has been frequently observed, B-cell NHL associated with HPS has been rarely reported. We report a case of hepatosplenic B-cell lymphoma associated with HPS in a 41-year-old woman who presented with fever of unknown origin. An abdominal CT scan revealed splenomegaly with focal splenic infarction. Splenectomy and a liver wedge biopsy showed sinusoidal-pattern infiltration of medium to large tumor cells with positive reaction to a B-lymphocyte marker. Findings on bone marrow examination showed proliferation of histiocytes with avid hemophagocytosis.

Portal, mesenteric, and splenic vein thromboses after splenectomy in a patient with chronic myeloid leukemia variant with thrombocythemic onset

Portal, mesenteric, or splenic vein thrombosis is a very uncommon complication with significant mortality in the patients undergoing splenectomy for hematologic disorders. We report a 49-year-old woman who developed portal, superior mesenteric, and splenic vein thromboses after splenectomy. Four years before the event, she presented with a marked thrombocytosis and was diagnosed to have chronic myeloid leukemia variant with thrombocythemic onset as evidence by Philadelphia (Ph1) chromosome and a b3a2 BCR/ABL transcript. Six weeks after splenectomy, she developed severe epigastric pain. The diagnosis of thromboses of portal, mesenteric, and splenic veins was made by computed tomography scan and Doppler sonogram. She was successfully treated with antegrade intraarterial urokinase therapy via superior mesenteric artery and long-term anticoagulant therapies. To our knowledge, our patient is the first case of portal, mesenteric, and splenic vein thromboses after splenectomy in a patient with CML variant with thrombocythemic onset successfully treated with antegrade intraarterial thrombolytic therapy followed by anticoagulant therapies.

Acute hemolytic crisis with fulminant hepatic failure as the first manifestation of Wilson's disease: a case report

We report a 27-year-old woman who developed Coombs' negative hemolytic anemia and fulminant hepatic failure as the initial manifestation of Wilson's disease. Unmeasurably low level of serum alkaline phosphatase provided a clue to the diagnosis of Wilson's disease. The diagnosis was established with the presence of Kayser-Fleischer ring, decreased serum ceruloplasmin level, and elevated urine and serum copper levels. In spite of repeated plasmapheresis, she died of multiorgan failure on the fifth hospital day.

A case of Marfan syndrome with acute monoblastic leukemia

We report on an 18-year-old man who had both acute monoblastic leukemia and Marfan syndrome. A diagnosis of Marfan syndrome was established by those characteristics of arachnodactyly, ectopia lentis, mitral valve prolapse, and mitral regurgitation. Findings on bone marrow examination of the patient showed that most of nucleated cells were monoblasts and immunophenotype of those cells showed CD13+, CD33+, CD56+, and HLA-DR+. To our knowledge, this is the second report of leukemia in Marfan syndrome in the world.

Prophylaxis for deep vein thrombosis with aspirin or low molecular weight dextran in Korean patients undergoing total hip replacement. A randomized controlled trial

150 Korean patients undergoing primary uncemented total hip replacement were randomized into 3 treatment groups for deep vein thrombosis (DVT) prophylaxis. Group A(50) were controls; Group B(50) received aspirin 1.2 g daily in 3 divided doses from 2 days before, to 14 days after surgery; Group C(50), received low molecular weight dextran 500 ml, infused intravenously at 50 ml/hour during surgery, and on each of the following 2 days. Contrast venograms were performed prior to surgery and 7-10 days after. The incidence of DVT was 20% in the control group, 12% in the aspirin group (p < 0.1 vs control), and 6% in the dextran group (p < 0.05 vs control). In patients developing DVT, the ratio of proximal to distal thrombi was increased in the control group as compared to treated groups (4:1 in the control group vs 1.5:1 in the treated groups). Both aspirin and dextran were well tolerated. Obesity (p < 0.05) and long-term administration of steroids (p < 0.05) were risk factors for deep vein thrombosis which reached statistical significance in the control group. Intraoperative venograms performed on 10 patients, showed that hip flexion (mean 40.4 degrees) plus adduction (mean 11.5 degrees) plus internal rotation (mean 81.5 degrees), resulted in severe twisting or kinking of the femoral vein with stagnation of blood flow. Low molecular weight dextran significantly reduce the incidence of deep venous thrombosis and aspirin, though less effective, had a similar effect.

A case of chronic graft-versus-host-disease following allogeneic peripheral blood stem cell rescue for poor graft function after bone marrow transplantation

To overcome poor graft function after allogeneic bone marrow transplantation (BMT), the use of peripheral blood stem cells (PBSC) instead of bone marrow is gaining more popularity because of its advantages. There may, however, be an increased risk of graft-versus-host-disease (GVHD) because of the large number of lymphocytes present in a leukapheresis product. An 18-year-old man with severe aplastic anemia underwent an allogeneic BMT using his HLA-identical sister. After initial excellent graft take for 8 months, his blood counts gradually decreased to 2.8 x 10(9)/L of white cells and 28 x 10(9)/L of platelets with marrow cellularity of < 10%. After allogeneic granulocyte-colony stimulating factor mobilized PBSC rescue, the patient's blood counts recovered satisfactorily. Around 1 year after the boost, he developed chronic GVHD that responded to prednisolone and cyclosporin A. He is now well on low-dose steroids at day +1055 after PBSC rescue. The present case is the first experience of a long-term follow-up who underwent allogeneic PBSC rescue in Korea.

A new suggestion for the treatment of minimally displaced fractures of the greater tuberosity of the proximal humerus

Fourteen shoulders in 14 patients with minimally displaced fractures of the greater tuberosity of the proximal humerus were evaluated, at an average of 3 years, 7 months (range: 1 year to 6 years, 1 month) after the operation. For comparison this portion of the proximal humerus was measured using 100 Korean adult cadaveric humeri. The results of these preliminary studies suggest that the patients presenting with a one-part fracture of the greater tuberosity of the proximal humerus should be evaluated individually. In most patients in whom the displacement of the fragment is less than 5 mm, good results can be obtained with non-operative treatment. If the displacement of the fragment is more than 5 mm in young active patients, and more than 3 mm in individuals (especially athletes and heavy laborers) involved in overhead activity, the fragment should be mobilized, repaired, and fixed into its original bed or slightly inferolaterally.

Deep vein thrombosis after uncemented total hip replacement

One-hundred-fourteen consecutive cases of venography after primary uncemented total hip replacement were performed in a randomized trial to identify the natural incidence of deep vein thrombosis, the effectiveness of prophylactic regimens such as 1.2 grams of aspirin daily and low-molecular-weight dextran for 3 days, and other relative factors for the development of venous thrombosis. In addition, intraoperative venography was conducted in 10 patients to study the speed of the flow of contrast media in the femoral vein and the development of deep vein thrombosis and the extent of the twisting of the femoral vein during hip joint manipulation. The incidence of venous thrombosis in the control, aspirin, and dextran prophylaxis groups were 20%, 11.5%, and 5.2% respectively. The incidence in the aspirin group was reduced, but this was statistically insignificant. The dextran group showed a marked decrease in incidence, and the difference with the control group was statistically significant. With regard to the development site of venous thrombosis, it was prevalent in iliofemoral, lower femoral, and major calf vein in the control group, while the popliteal and major calf vein were the major site of thrombosis development in the aspirin and dextran groups. The risk factors affecting the incidence of the venous thrombosis are confirmed to be obesity and long-term administration of steroids. Hematologic analysis was meaningless in investigating the development of venous thrombosis. The reliable clinical sign and symptom suggestive of the development of venous thrombosis was the severe swelling on the entire portion of affected lower extremity. In the intraoperative venogram, no correlation was found between the venous blood flow speed and the development of venous thrombi. A remarkable change in the blood flow of the femoral vein was noticed when the hip joint was flexed an average of 40.4 degrees, adducted at 11.5 degrees, and internally rotated at 81.5 degrees. Especially, when the joint was internally rotated, severe kinking of the vein could be observed. Thus it seems desirable to reduce the duration of internal rotation of the hip joint as much as possible to prevent venous thrombosis.

Ubiquitin marks the reactive swellings of diffuse axonal injury

Ubiquitin is a protein that targets proteins for non-lysosomal degradation. It has been found to be present in a number of inclusions characteristic of neurodegenerative diseases. Using the fluid percussion model of closed head injury in the cat, a well-established model of diffuse axonal injury (DAI), we now report that the reactive axonal swellings and the retraction balls produced in this model stain positively with anti-ubiquitin immunohistochemistry. Furthermore, the affected axons become ubiquitin positive quickly (within the first 6 h after injury). Anti-ubiquitin immunohistochemistry compares well with the recently reported ability of antibodies to low molecular weight neurofilament proteins to demonstrate reactive axonal change in DAI, and it could provide additional clues to the pathogenesis of axonal transection.

Early assessment of neurologic deficits in the fluid percussion model of brain injury

This study was designed to quantify the early neurologic effects of brain injury elicited by fluid percussion to the dura of cats. Propofol was used for surgical anesthesia because recovery in normal animals from an intravenous infusion was found to be nearly complete within 2 h of cessation and absolutely complete by 4 h. In addition, a cat coma scale (CCS) was developed that reflects normal (CCS, 14) to moribund (CCS, 3) behavior. The CCS values at 6 h were compared with the force of injury expressed in atmospheres (atm), maximum blood pressure change, and gross neuropathology to ascertain which parameter might best account for the behavior observed after brain injury. The results showed that decreasing neurologic scores correlated well with increasing atmospheres of injury (Pearson's r 0.71, p < 0.001) but not with the rise in systolic blood pressure caused by the trauma (n = 29). Coma scores did correlate with the cross sectional area of ponto-mesencephalic lesions (Pearson's r = 0.51, p < 0.01) and proved to be significantly different in animals grouped according to lesion size of less or more than 3 mm in length (t test, p < 0.01). Thus the CCS and the pharmacologic properties of propofol permit an early analysis of the neurologic status in the feline fluid percussion model of brain injury. These procedures could facilitate the evaluation of early biochemical changes that affect behavior and of therapies designed to ameliorate the deleterious effects of head injury.

Constant current source for iontophoresis

A simple, battery-powered current source is described that is suitable for the iontophoresis of axonal tracing substances, such as Phaseolus vulgaris leucoagglutinin. Unlike the previous designs that form the basis of most commonly used iontophoretic devices, this circuit does not use operational amplifiers to provide controlled current. Instead, a pair of bipolar transistors that can be selected to provide a compliance of many hundreds of volts form the regulating circuitry.

Capacitance compensation and bridge balance adjustment in intracellular recording from dendritic neurons

Under most experimental conditions in intracellular recording, the proper adjustment of the amplifier is essential for the interpretation of the signals recorded from neurons. It is considered possible to accurately align the capacitance compensation and bridge balance adjustments of the amplifier simultaneously with the recording of membrane potential of an impaled cell if a number of conditions are met. In the strictest sense, these conditions are met only if: (1) the neuron is isopotential and if its electrical behavior can be adequately described using a single exponential decay constant, and if (2) that decay time constant is much longer than that of the microelectrode. These conditions cannot usually be satisfied. Because intracellular adjustment of capacitance compensation and bridge balance is necessary in many circumstances, it is desirable, to know whether any of the methods for performing these adjustments are accurate when used under less strict constraints, and to assess the nature and degree of the error that can be expected when the constraints are ignored. The results of computer simulations of a simple intracellular recording amplifier, microelectrode and a dendritic neuron model consisting of an isopotential cell and terminated finite equivalent cylinder representation of the dendrites are presented here. These studies show that the introduction of fast components of the response to intracellular current transients by the redistribution of applied charge in dendrite neurons may sometimes make it impossible to correctly apply the conventional methods of capacitance compensation and bridge balance. If the high-frequency response of the intracellular recording amplifier has sufficient fidelity, however, these adjustments can be made to a sufficient degree of accuracy using the response to sine wave calibration signals of varying frequency.

Interactions between the lateral hypothalamus and the periaqueductal gray

Anatomical and physiological experiments were conducted to characterize the interactions between the lateral hypothalamus (LH) and the periaqueductal gray (PAG) and to determine the role of neurotensin in their interaction. Anatomical studies using injection of Phaseolus vulgaris leucoagglutinin into the LH showed an extensive projection to the ventromedial and the ventrolateral PAG and a less dense projection to the medial and dorsal parts of this region. Physiological experiments were performed on both deeply and lightly anesthetized animals. Electrical stimulation of the LH caused excitation of PAG cells with an onset latency of approximately 14 msec. There was a strong correlation between the response of PAG cells to electrical stimulation and injection of glutamic acid into the LH. Electrical or chemical stimulation of the LH produced an increase in tail flick latency in the lightly anesthetized animals that outlasted the stimulation period. There was a strong correlation between the response of PAG cells to electrical and chemical stimulation of the LH and their response to pressure-injected neurotensin. It is concluded that an excitatory projection from the LH to PAG exists which may involve neurotensin. This pathway may be involved in the analgesia produced by LH stimulation.

Monosynaptic inhibitory postsynaptic potentials from lateral habenula recorded in dorsal raphe neurons

The inhibitory response evoked in presumably serotonergic dorsal raphe neurons by stimulation of the lateral habenular nucleus was examined in the rat using intracellular recording techniques. Electrical stimulation of the lateral habenula produces a long-lasting hyperpolarization in dorsal raphe neurons having the slow spontaneous firing pattern (0.5-1.5 spikes/sec) and broad action potential (greater than 1 msec) indicative of serotonergic neurons. The hyperpolarizing response is reversed by hyperpolarizing current injection or by increasing intracellular Cl-concentration and is thus an inhibitory postsynaptic potential (IPSP) due to conductance increase to Cl-. The mean latency of the IPSP is 7.0 msec, which implies a mean conduction velocity for habenulo-raphe axons of 1.2 m/sec. The latency of the response could be demonstrated to be unaffected by changes in stimulus strength, indicating that the IPSP is monosynaptic, which is in agreement with recent anatomical data. Intracellular horseradish peroxidase labeling of responding neurons shows them to have a morphology typical of serotonergic dorsal raphe neurons.

Intracellular horseradish peroxidase labeling of rapidly firing dorsal raphe projection neurons

The class of rapidly firing neurons in the dorsal raphe of the rat was examined using extracellular recording and intracellular injection of horseradish peroxidase. Rapidly firing neurons (termed F-cells in this report) continue to fire at high spontaneous rates during intracellular recording. This and their brief (ca. 1 ms) and symmetrical action potentials distinguish them from the slowly firing, presumably serotonergic neurons in dorsal raphe. Intracellular labeling with horseradish peroxidase reveals that F-cells have small (10-15 microns) spherical, multipolar or piriform somata. Somatic spines are sparse or entirely absent. The general form of the dendritic tree is radiant and poorly branching. However, the dendrites of F-cells take two forms, with both forms being present on the same neuron so that besides having a complement of poorly branching dendrites, each F-cell has at least one dendrite with a slightly tufted branching pattern: a short primary dendrite gives rise to 3 or 4 secondary branches. The axons of F-cells project from the nucleus. They align themselves along the trajectories of known dorsal raphe efferent pathways, coursing laterally and ventrorostrally beyond the bounds of the nucleus. Morphometric measurements of retrogradely labeled dorsal raphe projection neurons provide additional evidence that small projection neurons exist.

The morphology and divergent axonal organization of midbrain raphe projection neurons in the rat

The morphology of dorsal raphe neurons was examined using intracellular injections of horseradish peroxidase (HRP) and the Golgi technique. Light microscopic examination of HRP-labeled projection neurons revealed a neuron type with radiating, poorly branched and sparsely spined dendrites and terminal dendritic thickets. The stem axon of these neurons left the nucleus ventrally but gave off a beaded collateral while still within the parent cell's dendritic domain. Somatodendritic morphology from Golgi-Kopsch stained material coincided with intracellular HRP findings and the dorsal raphe may consist of varieties of one basic morphological type of neuron. Intracellular recordings made during the HRP injection experiments confirmed that stimulation of the ventral medial tegmentum elicited an antidromic action potential and an inhibitory postsynaptic potential in dorsal raphe projection neurons. The order of axonal projections arising from the midbrain raphe nuclei was examined using a double retrograde axonal tracing technique. After paired HRP and [3H] wheat germ agglutinin injections within certain projection targets of the dorsal and median raphe neurons (caudate-putamen, amygdala, hippocampus, substantia nigra and locus coeruleus), each target structure was found to have its own unique representation within a topographically distinct portion of one or more of the raphe subgroups. Neurons projecting to the caudate-putamen and substantia nigra occupied rather rostral portions. Neurons projecting to the hippocampus and locus coeruleus resided more caudally. Neurons projecting to the amygdala were situated intermediately. Overall, rostrocaudal topography in the intranuclear distributions of raphe projection neurons resulted in the formation of complex overlap zones where collateralized neurons always resided.

An intracellular HRP study of the rat globus pallidus. II. Fine structural characteristics and synaptic connections of medially located large GP neurons

In order to classify the presynaptic elements contacting the principle class of globus pallidus neurons, electron microscopic examination of serial sections made from a medially located large globus pallidus neuron, labeled with intracellular horseradish peroxidase, was undertaken. In addition, the use of labeled and light microscopically reconstructed material allowed us to quantitatively determine the distribution of each bouton type along the soma and dendrites. Six types of presynaptic terminals contacting the labeled cell have been recognized. Type 1 endings, the most numerous (84%), make symmetrical contacts on all portions of the cell, except spines, contain large pleomorphic, and a few large dense-core vesicles. Type 2 endings are filled with small spherical-to-ellipsoidal synaptic vesicles. They make asymmetrical contacts only with higher-order dendrites and account for 12% of synaptic contacts onto the labeled neuron. Type 3 endings are large, contain sparsely distributed large pleomorphic vesicles, and make two symmetrical synapses per bouton, one onto a spine head and the other onto the underlying dendritic shaft. They are infrequent (0.2%), being found only in association with dendritic spines. Type 4 endings contain large pleomorphic synaptic vesicles and no dense-core vesicles. They make symmetrical contacts with the short primary dendrites. Type 5 endings contain a mixture of small clear pleomorphic vesicles and numerous large dense-core vesicles. They contact only the cell body and the short primary dendrites, making up 20% of somatic synaptic contacts but less than 1% of contacts onto dendrites. Type 6 boutons contain oval and flattened synaptic vesicles and establish symmetrical contacts with higher-order dendritic branches and the cell body.

Bridge balance in intracellular recording; introduction of the phase-sensitive method

Passing current through the microelectrode during intracellular recording produces an artifactual voltage-drop across the electrode's resistance. In modern biological amplifiers, the means of removing this artifact is through what is no more than an analog arithmetic unit which subtracts a voltage, having some fixed proportion to the current being injected, from the voltage appearing at the input to the amplifier. Various techniques have evolved for determining that fixed proportion, an operation which has come to be referred to as bridge balance, and these are reviewed. A new method is presented for determining bridge balance and another amplifier parameter which affects current injection, capacitance neutralization. Essentially, a sinusoidal current is passed through the electrode and preparation at a frequency high enough so that the cellular membrane presents negligable impedance but low enough so that the electrode appears as nearly a pure resistance. A set of analytical formulations is presented which describes the system and which is useful in choosing the best frequency of the test sinusoidal signal. This choice, part of the experimental design, is based on the predicted time constants of the recorded cell and the recording electrode. In using the phase-sensitive method, the capacitance neutralization of the recording amplifier is adjusted until there is no phase error in the injected current. Bridge balance can then be adjusted until no sinusoidal signal is visible at the output of the amplifier. Both bridge balance and correction of capacitance compensation can be automatically and continuously performed during intracellular recording by incorporating a phase-sensitive alternating current (AC) voltmeter (i.e. a lock-in amplifier) into the system. This permits accurate measurement of intracellular potential during current injection even though the resistance of the electrode might be changing.