Extracellular ATP is a homeostatic messenger that mediates cell‒cell communication in physiological processes and psychiatric diseases

Neuronal activity is the basis of information encoding and processing in the brain. During neuronal activation, intracellular ATP is generated to meet the high-energy demands. Meantime, ATP is secreted, increasing the extracellular ATP concentration and acting as a homeostatic messenger that mediates cell‒cell communication to prevent aberrant hyperexcitability of the nervous system. In addition to the confined release and fast synaptic signaling of classic neurotransmitters within synaptic clefts, ATP can be released by all brain cells, diffuses widely and targets different types of purinergic receptors on neurons and glial cells, making it possible to orchestrate brain neuronal activity and participate in various physiological aspects, such as sleep and wakefulness, learning and memory, and feeding. Dysregulation of extracellular ATP leads to a "destabilizing" effect on the neural network, as found in the etiopathology of many psychiatric diseases, including depression, anxiety, schizophrenia, and autism spectrum disorder. This review summarizes advances in the understanding of the mechanisms by which extracellular ATP serves as an intercellular signaling molecule to regulate neural activity, with a focus on how it maintains the homeostasis of neural networks. In particular, we also focus on neural activity issues resulting from dysregulation of extracellular ATP and propose that aberrant levels of extracellular ATP may play a role in the etiopathology of some psychiatric diseases, highlighting the potential therapeutic targets of ATP signaling in the treatment of these psychiatric diseases. Finally, we suggest potential avenues to further elucidate the role of extracellular ATP in intercellular communication and psychiatric diseases.

Dopamine D2 receptors in pyramidal neurons in the medial prefrontal cortex regulate social behavior

Drugs acting on dopamine D2 receptors are widely used for the treatment of several neuropsychiatric disorders, including schizophrenia and depression. Social deficits are a core symptom of these disorders. Pharmacological manipulation of dopamine D2 receptors (Drd2), a Gi-coupled subtype of dopamine receptors, in the medial prefrontal cortex (mPFC) has shown that Drd2 is implicated in social behaviors. However, the type of neurons expressing Drd2 in the mPFC and the underlying circuit mechanism regulating social behaviors remain largely unknown. Here, we show that Drd2 were mainly expressed in pyramidal neurons in the mPFC and that the activation of the Gi-pathway in Drd2+ pyramidal neurons impaired social behavior in male mice. In contrast, the knockdown of D2R in pyramidal neurons in the mPFC enhanced social approach behaviors in male mice and selectively facilitated the activation of mPFC neurons projecting to the nucleus accumbens (NAc) during social interaction. Remarkably, optogenetic activation of mPFC-to-NAc-projecting neurons mimicked the effects of conditional D2R knockdown on social behaviors. Altogether, these results demonstrate a cell type-specific role for Drd2 in the mPFC in regulating social behavior, which may be mediated by the mPFC-to-NAc pathway.

Breakage and Disappearance of a Part of the Midline Catheter Tip During Insertion

Midline catheters have been proposed as alternatives to central venous catheters and peripherally inserted central catheters. Midline catheters reduce the incidence of overall needle stick injuries during hospitalization, have lower complication rates than central venous catheters or peripherally inserted central catheters, and provide potential cost benefits for hospitals. Complications with midline catheters are similar to those of other intravenous catheters, and intravenous catheter breakage is very rare and invasive. We report a case wherein a midline catheter tip was broken during insertion and removed by open surgery. For the safe use of midline catheters, accurate and delicate insertion techniques should be practiced. More case studies are warranted to verify the usefulness and convenience of various types of midline catheters for their universal use.

The Memory Orchestra: Contribution of Astrocytes

For decades, memory research has centered on the role of neurons, which do not function in isolation. However, astrocytes play important roles in regulating neuronal recruitment and function at the local and network levels, forming the basis for information processing as well as memory formation and storage. In this review, we discuss the role of astrocytes in memory functions and their cellular underpinnings at multiple time points. We summarize important breakthroughs and controversies in the field as well as potential avenues to further illuminate the role of astrocytes in memory processes.

Observation of a Strongly Isospin-Mixed Doublet in ^{26}Si via β-Delayed Two-Proton Decay of ^{26}P

β decay of proton-rich nuclei plays an important role in exploring isospin mixing. The β decay of ^{26}P at the proton drip line is studied using double-sided silicon strip detectors operating in conjunction with high-purity germanium detectors. The T=2 isobaric analog state (IAS) at 13 055 keV and two new high-lying states at 13 380 and 11 912 keV in ^{26}Si are unambiguously identified through β-delayed two-proton emission (β2p). Angular correlations of two protons emitted from ^{26}Si excited states populated by ^{26}P β decay are measured, which suggests that the two protons are emitted mainly sequentially. We report the first observation of a strongly isospin-mixed doublet that deexcites mainly via two-proton decay. The isospin mixing matrix element between the ^{26}Si IAS and the nearby 13 380-keV state is determined to be 130(21) keV, and this result represents the strongest mixing, highest excitation energy, and largest level spacing of a doublet ever observed in β-decay experiments.

The ATP Level in the Medial Prefrontal Cortex Regulates Depressive-like Behavior via the Medial Prefrontal Cortex-Lateral Habenula Pathway

BACKGROUND

Depression is the most common mental illness. Mounting evidence suggests that dysregulation of extracellular ATP (adenosine triphosphate) is involved in the pathophysiology of depression. However, the cellular and neural circuit mechanisms through which ATP modulates depressive-like behavior remain elusive.

METHODS

By use of ex vivo slice electrophysiology, chemogenetic manipulations, RNA interference, gene knockout, behavioral testing, and two depression mouse models, one induced by chronic social defeat stress and one caused by a IP3R2-null mutation, we systematically investigated the cellular and neural circuit mechanisms underlying ATP deficiency-induced depressive-like behavior.

RESULTS

Deficiency of extracellular ATP in both defeated susceptible mice and IP3R2-null mutation mice led to reduced GABAergic (gamma-aminobutyric acidergic) inhibition and elevated excitability in lateral habenula-projecting, but not dorsal raphe-projecting, medial prefrontal cortex (mPFC) neurons. Furthermore, the P2X2 receptor in GABAergic interneurons mediated ATP modulation of lateral habenula-projecting mPFC neurons and depressive-like behavior. Remarkably, chemogenetic activation of the mPFC-lateral habenula pathway induced depressive-like behavior in C57BL/6J mice, while inhibition of this pathway was sufficient to alleviate the behavioral impairment in both defeated susceptible and IP3R2-null mutant mice.

CONCLUSIONS

Overall, our study provides compelling evidence that ATP level in the mPFC is critically involved in regulating depressive-like behavior in a pathway-specific manner. These results shed new light on the mechanisms underlying depression and the antidepressant effect of ATP.

[The 498th case: rash, fever and hematuria]

A 50-year-old man was admitted to the Department of Rheumatology at Peking Union Medical College Hospital with rash for 6 months, and fever and hematuria for 5 months. The main clinical manifestations included fever, fatigue, purpura, hematuria and thrombocytopenia. He was positive for antinuclear antibody (ANA), anti-neutrophil cytoplasmic antibodies (ANCA) and rheumatoid factor (RF), and had low complement levels. Initial blood culture, echocardiography and chest CT showed no signs of infection. Diagnosis of connective tissue disease was made initially. His disease improved under treatment with glucocorticoids and immunosuppressive agents, but relapsed when glucocorticoids were tapered. After admission, the diagnosis was reconsidered, and infective endocarditis was finally diagnosed with repeated positive blood cultures and vegetations detected by transesophageal echocardiography. Amoxicillin and clavulanate potassium were initiated, and surgery was performed. His symptoms finally recovered gradually.

[Effects of plasma lipopolysaccharide changes on platelet release of vascular endothelial growth factor and thromobospondin-1 in patients with cirrhotic portal hypertension after TIPS procedure]

Objective: To investigate the effects of plasma lipopolysaccharide (LPS) concentration changes on platelet release of vascular endothelial growth factor (VEGF) and thrombospondin (TSP)-1 in patients with decompensated cirrhotic portal hypertension after transjugular intrahepatic portosystemic shunt (TIPS) procedure. Methods: 169 cases with cirrhotic portal hypertension were enrolled, of which 81 cases received TIPS treatment. LPS, VEGF, and TSP-1 concentrations with different Child-Pugh class in peripheral blood plasma of patients were measured. After pre-incubation of normal human platelets with different concentrations of LPS and stimulated by collagen in vitro, platelet PAC-1 expression rate, VEGF, and TSP-1 concentrations were detected. PAC-1 expression rate and the concentrations of LPS, VEGF and TSP-1 in peripheral blood plasma of patients before and after TIPS procedure were detected. The relationship between plasma LPS, VEGF and TSP-1 concentrations and Child-Pugh score changes in patients after TIPS procedure was analyzed. Statistical analysis was performed by t-test, one-way ANOVA or Pearson's rho according to different data. Results: Plasma LPS and TSP-1 concentrations were significantly higher in Child-Pugh class C patients than class A and B, but the concentration of plasma VEGF was significantly lower than class A and B (P < 0.01). In vitro experiments showed that concentration of LPS, TSP-1, and platelet PAC-1 expression rate was higher in the supernatant, but the difference in the concentration of VEGF in the supernatant was not statistically significant. Portal vein pressure and platelet activation were significantly decreased (P < 0.01) in patients after TIPS procedure. Portal venous pressure, platelet activation, plasma LPS, and TSP-1 levels were significantly decreased continuously, while VEGF levels were significantly increased continuously after TIPS procedure. Plasma LPS concentration was positively correlated with TSP-1 concentration (r = 0.506, P < 0.001), and negatively correlated with VEGF concentration (r = -0.167, P = 0.010). Child-Pugh score change range was negatively correlated with change range of plasma VEGF concentration (r = -0.297, P = 0.016), and positively correlated with change range of plasma TSP-1 concentration (r = 0.145, P = 0.031) after TIPS. Conclusion: Portal venous pressure gradient, plasma LPS concentration and corresponding platelet activation was decreased in cirrhotic portal hypertension after TIPS procedure, and with TSP-1 reduction and VEGF elevation it is possible to reduce the liver function injury caused by portal venous shunt.

Upregulated NMDAR-mediated GABAergic transmission underlies autistic-like deficits in Htr3a knockout mice

Mutations in serotonin pathway genes, especially the serotonergic receptor subunit gene HTR3A, are associated with autism. However, the association of HTR3A deficiency with autism and the underlying mechanisms remain unknown.

Methods: The Htr3a knockout (KO) mice were generated using transcription activator-like effector nuclease technology. Various behavior tests, including social interaction, social approach task, olfactory habituation/dishabituation, self-grooming, novel object recognition, contextual fear conditioning, elevated plus maze, open field and seizure susceptibility, were performed to assess the phenotypes. Transcriptome sequencing was carried out to search for molecular network and pathways underlying the phenotypes. Electrophysiological recordings, immunoblotting, immunofluorescence staining, immunoprecipitation, and quantitative real-time PCR were performed to verify the potential mechanisms. The N-methyl-D-aspartate receptor (NMDAR) antagonist memantine was used to treat the KO mice for rescuing the phenotypes.

Results: The Htr3a KO mouse model showed three phenotypic domains: autistic-like behaviors (including impaired social behavior, cognitive deficits, and increased repetitive self-grooming), impaired memory, and attenuated susceptibility to pentylenetetrazol-induced seizures. We observed enhanced action potential-driven γ-aminobutyric acid-ergic (GABAergic) transmission in pyramidal neurons and decreased excitatory/inhibitory (E/I) ratio using the patch-clamp recording. Transcriptome sequencing on the hippocampus revealed the converged pathways of the dysregulated molecular networks underlying three phenotypic domains with upregulation of NMDAR. We speculated that Htr3a KO promotes an increase in GABA release through NMDAR upregulation. The electrophysiological recordings on hippocampal parvalbumin-positive (PV⁺) interneuron revealed increased NMDAR current and NMDAR-dependent excitability. The NMDAR antagonist memantine could rescue GABAergic transmission in the hippocampus and ameliorate autistic-like behaviors of the KO mice.

Conclusion: Our data indicated that upregulation of the NMDAR in PV⁺ interneurons may play a critical role in regulating GABAergic input to pyramidal neurons and maybe involve in the pathogenesis of autism associated with HTR3A deficiency. Therefore, we suggest that the NMDAR system could be considered potential therapeutic target for autism.

Large Isospin Asymmetry in ^{22}Si/^{22}O Mirror Gamow-Teller Transitions Reveals the Halo Structure of ^{22}Al

β-delayed one-proton emissions of ^{22}Si, the lightest nucleus with an isospin projection T_{z}=-3, are studied with a silicon array surrounded by high-purity germanium detectors. Properties of β-decay branches and the reduced transition probabilities for the transitions to the low-lying states of ^{22}Al are determined. Compared to the mirror β decay of ^{22}O, the largest value of mirror asymmetry in low-lying states by far, with δ=209(96), is found in the transition to the first 1^{+} excited state. Shell-model calculation with isospin-nonconserving forces, including the T=1, J=2, 3 interaction related to the s_{1/2} orbit that introduces explicitly the isospin-symmetry breaking force and describes the loosely bound nature of the wave functions of the s_{1/2} orbit, can reproduce the observed data well and consistently explain the observation that a large δ value occurs for the first but not for the second 1^{+} excited state of ^{22}Al. Our results, while supporting the proton-halo structure in ^{22}Al, might provide another means to identify halo nuclei.

[Current status of occupational stress among medical staff in Shenzhen, China and related influencing factors]

Objective: To investigate the current status of occupational stress in medical staff in Shenzhen, China, and to provide a reference for developing health administrative policy and reducing occupational stress in medical staff. Methods: From January to June, 2018, a cross-sectional survey was performed in 992 medical workers who were selected from 2 municipal hospitals and 2 district hospitals by stratified random sampling. General information was collected, Occupational Stress Inventory-Revised Edition was used to investigate occupational stress, and univariate and multivariate analyses were performed based on a descriptive analysis of related results. Results: For the medical staff in Shenzhen, the scores of Occupational Role Questionnaire, Personal Stress Questionnaire, and Personal Resources Questionnaire were 185.67±17.55, 108.45±15.56, and 122.74±16.56, respectively. Age, degree of education, type of work, job title, professional title, and permanent or temporary job were influencing factors for occupational task (P<0.05) ; age, working years, type of work, and night shift were influencing factors for personal stress response (P<0.05) ; working years, type of work, professional title, and weekly working hours were influencing factors for personal coping resources (P<0.05) . Conclusion: There is a high degree of occupational stress among medical staff in Shenzhen, and it is recommended to improve medical resources in Shenzhen, reduce occupational stress among medical staff, and increase coping resources.

Cardiac μ-opioid receptor contributes to opioid-induced cardioprotection in chronic heart failure

BACKGROUND

The therapeutic potential of cardiac μ-opioid receptors in ischaemia-reperfusion (I/R) injury during opioid-modulating diseases, such as heart failure, is unknown. We aimed to explore the changes of cardiac μ-opioid receptor expression during heart failure, and its role in opioid-induced cardioprotection.

METHODS

Rats received doxorubicin (DOX) or were subjected to coronary artery ligation to induce heart failure, or received normal saline (NS) as control. Hearts from NS or DOX rats were isolated and subjected to myocardial ischaemia and reperfusion in an in vitro perfusion system. The opioid [D-Ala,²N-MePhe,⁴ Gly-ol]-enkephalin (DAMGO), with a high μ-opioid receptor specificity, morphine, and remifentanil were administrated before I/R with or without opioid receptor antagonists, or an extracellular signal-regulated kinase (ERK) inhibitor.

RESULTS

Cardiac μ-opioid receptor mRNA concentrations were 3.2 times elevated in DOX-treated rats compared with NS rats, while cardiac μ-opioid receptor protein concentrations showed 6.1- and 3.5-fold increases in DOX-treated and post-infarcted rats, respectively. DAMGO reduced I/R-caused infarct size, expressed as the ratio of area at risk, from 0.50 (0.04) to 0.25 (0.03) in failing rat hearts, but had no effect on infarct size in control hearts. DAMGO promoted phosphorylation of ERK and glycogen synthase kinase (GSK)-3β only in failing hearts. DAMGO-mediated cardioprotection was blocked by an ERK inhibitor. The μ-opioid receptor antagonist D-Pen-Cys-Tyr-D-Trp-Orn-Thr-Pen-Thr-NH2 (CTOP) prevented morphine- and remifentanil-induced cardioprotection and phosphorylation of ERK and GSK-3β in failing hearts. In contrast, δ- and κ-opioid receptor selective antagonists were less potent than CTOP in the failing hearts.

CONCLUSIONS

Cardiac μ-opioid receptors were substantially up-regulated during heart failure, which increased DAMGO-induced cardioprotection against I/R injury.

Solid pseudopapillary neoplasm of the pancreas with liver metastasis initially misinterpreted as benign haemorrhagic cyst

Solid pseudopapillary neoplasm (SPN) of the pancreas is considered a low-malignant neoplasm with a good prognosis. However, 5% to 15% of patients with SPNs develop metastatic disease, most commonly in the liver. Metastatic hepatic malignancies that show pseudocystic features are rare. Here we describe the case of a middle-aged female with a cystic liver metastasis from SPN. To the best of our knowledge, SPN with a single cystic liver metastasis has not been described, although these tumours frequently undergo haemorrhagic-cystic degeneration. Thus, in these patients the marked cystic change could be misinterpreted as a benign lesion.

Initial empiric antibiotic therapy for community-acquired pneumonia in Chinese hospitals

OBJECTIVES

Studies on treatment of community-acquired pneumonia (CAP) in China are scarce. We performed a study to investigate empiric antibiotic practices for patients hospitalized with CAP in China and the risk factors for treatment failure.

METHODS

Data were collected from a national Chinese hospitalization database. Adult patients who were diagnosed with CAP between 1 October 2014 and 30 September 2015 were identified. We studied initial empiric antibiotic regimens, microbiologic sampling, treatment failure, in-hospital mortality and length of hospital stay.

RESULTS

We included 18 043 adult patients from 185 hospitals who met all the study inclusion criteria. The most common initial antibiotic regimen for CAP was monotherapy with a fluoroquinolone (14.8%, 2671/18 043). The most common initial antibiotic (used alone or in combination with other antibiotics) was levofloxacin (15.7%, 4597/29 278 (this denominator represents the total number of initial antibiotics)). The microbiologic sampling rate was 26.9% (4851/18 043). A total of 4050 (22.4%) of 18 043 patients experienced treatment failure. Multivariate logistic regression demonstrated that older age, male sex, coexisting lung cancer and use of regimens not covering atypical pathogens were risk factors for treatment failure. In-hospital mortality was 2.1% (380/18 043). The median hospital length of stay was 11 days (interquartile range, 8-15 days).

CONCLUSIONS

Patients receiving Chinese guideline-adherent regimens had better outcomes, and atypical pathogen active regimens were associated with a lower treatment failure rate and shorter length of hospital stay.

Duplication polymorphisms in exon 4 of κ-casein gene in yak breeds/populations

The objective of this study was to compare 12 bp-duplication polymorphisms in exon 4 of the κ-casein gene among 3 breeds/populations of yak (Bos grunniens). Genomic DNA was extracted from yak blood or muscle samples (N = 211) and a partial sequence of exon 4 of κ-casein gene was amplified by polymerase chain reaction. A polyacrylamide gel electrophoresis assay of the products (169 bp) revealed 2 variants. These variants differed in a 12-bp duplication of the nucleotide sequence corresponding to amino acids 147-150 (Glu-Ala-Ser-Pro) or 148-151 (Ala-Ser-Pro-Glu). The genotype frequency and gene frequency of the 2 κ-casein variants differed among the 3 yak breeds/populations. The long form of the κ-casein gene was the predominant allele, and the Jiulong yak showed the highest frequency of the short form variant of the κ-casein gene. In addition, 2 nucleotide differences resulting in amino acid substitutions were also identified in yaks. These results are significant for designing a breeding strategy to improve the genetic makeup of yak herds.

Correlation between carbonic anhydrase IX (CA-9), XII (CA-12) and hypoxia inducible factor-2α (HIF-2α) in breast cancer

Hypoxia inducible factor 2α (HIF-2α) can trigger the expression of several genes related to many aspects of tumor progress under hypoxia. As an independent factor, the role of HIF-2α is different from other hypoxia-mediated elements, including HIF-1α. Carbonic anhydrase (CA) were also regarded as important enzymes that involve in the tumor microenvironment pH. To find clinical-pathological features of breast cancer in plateau and explore the impact of CAIX, XII (CA-9, CA-12) and HIF-2α on patients with breast cancer. Clinical data were collected and summarized in 94 patients with breast cancer. The expression of HIF-2α, CA-9 and CA-12 were detected, using immunohistochemistry of specimens. The relation between expressions and clinical-pathology was analyzed. Under normoxia, hypoxia, and after being pretreated with the JNK inhibitor SP600125, HIF- 2α, CA-9 and CA-12 expressions were detected, and adhesion and invasion assays were performed in MCF-7 cells and HIF- 2α shRNA cells, respectively. There are higher expressions of HIF-2α in tumor classification 2 and clinical stage 2 (P < 0.05). High expression of CA-12 was observed in clinical stage 2 (P < 0.05). CA-9 expression is significantly correlated with CA-12 expression (r = 0.376, P = 0.0001). HIF-2α expression is not correlated with both CA-9 expression (P = 0.21) and CA-12 expression (P = 0.27). Breast cancer cells in vitro showed that HIF-2α, CA-9 or CA-12 had an increase expression under hypoxia (1% O2). CA-9 or CA-12 expression was observed in HIF-2α shRNA cells. JNK inhibitor SP 600125 reduced the HIF-2α expression and inhibited the adhesion and invasion of breast cancer cell. Slight inhibition effect on CA-9 and CA-12 expression was found. In conclusion, HIF-2α, CA-9 and CA-12 are important hypoxia responsive elements in breast cancer. HIF-2α was involved in metastasis and invasion of breast cancer cells under hypoxia, by the involvement of c-Jun NH2-terminal kinase (JNK) signal pathway. CA-9 and CA-12 may tend to be regulated by HIF-1α more often than by HIF-2α under hypoxia.

Synthesis of substituted cinnamoyl-tyramine derivatives and their platelet anti-aggregatory activities

Substituted cinnamoyl-tyramine derivatives were synthesized by DCC-coupling of substituted cinnamic acid with tyramine or tyramine methyl-1-ether to evaluate PAF-receptor binding antagonistic activities and inhibitory activities on PAF-induced platelet aggregation with interest on structure-activity relations. The results show that 3,4-dimethoxy-cinnamoyl tyramine-amide or its methyl ether have significant PAF-receptor binding antagonistic activity and platelet anti-aggregatory activities.

Endoscopic submucosal dissection with sentinel node navigation surgery for early gastric cancer

We combined endoscopic submucosal dissection (ESD) and sentinel node navigation surgery with the purpose of achieving complete resection of early gastric cancer while preserving the organ and assessing pathological nodal status. A total of 13 patients with cT1( ≤ 3 cm)N0 early gastric cancer underwent combined ESD and sentinel node navigation surgery (ESN) at a single tertiary referral center. Sentinel node navigation surgery using indocyanine green was performed during ESD and all suspected sentinel nodes were removed laparoscopically and examined intraoperatively. ESN was converted to gastrectomy with D2 dissection if there was evidence of metastasis on frozen section. ESN was completed in 12 patients and in 1 patient was converted to gastrectomy after sentinel node navigation surgery. En bloc tumor resection was achieved in all cases. Two patients underwent additional gastrectomy because they had tumor-positive vertical margins. In all cases ESN was conducted without intraoperative or postoperative adverse events. ESN is a feasible minimally invasive procedure that allows en bloc tumor resection to be achieved while assessing the pathological status of the lymph nodes.

A novel lift-off method for fabricating patterned and vertically-aligned W18O49 nanowire arrays with good field emission performance

A novel lift-off method has been developed for fabricating patterned W(18)O(49) nanowires in vertical arrays and on a large scale. These W(18)O(49) nanowire arrays have an average diameter of about 30 nm, and their lengths range from 2-3 μm. In every pattern of a 2 inch sample, the nanowires exhibit the same morphology and growth density. They are single crystals with monoclinic structure and grow along the [010] direction. Field emission (FE) measurements show that they have a turn-on field of 6.2 V μm(-1) and their emission current density can reach 500 μA cm(-2) at an electric field of 10.9 V μm(-1). Because the W(18)O(49) nanowire patterns synthesized by this simple method still have good FE performance, comparable to many cathode nanostructures with excellent FE properties, it suggests that it may provide an effective and simple preparation technique for patterned growth of nanowire arrays in future FE applications.

Effect of drug-eluting metal stents in benign esophageal stricture: an in vivo animal study

BACKGROUND AND STUDY AIMS

The aim of this study in canines was to investigate the effectiveness and safety of self-expandable metal stents, which were coated with paclitaxel to minimize the tissue response.

MATERIALS AND METHODS

14 dogs (5-10 kg) were randomly allocated to two groups. Drug-eluting stents (DES, n = 7) or nondrug-eluting stents (non-DES, n = 7) were endoscopically inserted and fixed in the esophagus of healthy dogs. Every 2 weeks, for a maximum period of 8 weeks, an endoscopic examination was performed to evaluate the status of stent insertion, the grade of tissue hyperplasia, and mucosal change at both ends of the stent.

RESULTS

One case of stent migration was observed after 4 weeks in the non-DES group. In this group, tissue reaction and hyperplasia remained for more than 4 weeks after stent insertion. By contrast, an endoscopic examination of the surrounding esophageal mucosa in the DES group showed very little tissue reaction, and the stent was easily separated from the esophageal tissue.

CONCLUSION

Although further studies are required to confirm our results, we suggest that these newly designed DES may provide an alternative tool to manage refractory benign esophageal stricture.

Ca2+Cascade and Meiotic Resumption of the Caprine Primary Oocyte

In this study, we investigated the fluctuations of concentration of intracytoplasmic free Ca(2+) during in vitro maturation of caprine primary oocytes and its role in meiotic resumption. Oocytes that were extracted from caprine ovaries were cultured and allowed to mature in vitro to determine their developmental stages including germinal vesicle (GV), germinal vesicle breakdown (GVBD), metaphase of the first meiotic division (MI) and metaphase of the second meiotic division (MII). Intracytoplasmic free Ca(2+) turnovers of caprine oocytes at these different developmental stages were measured using the calcium fluorescent probe Fura-2/AM (C(44)H(47)N(3)O(24)) to investigate the dynamics of cytosolic free Ca(2+) during in vitro maturation of oocytes and the role of Ca(2+) in inducing the initiation of meiotic resumption of oocytes. Moreover, the oocytes were cultured in Ca(2+) culture medium and Ca(2+)-free culture medium to examine the effect of extracellular Ca(2+) on the oocyte maturation. The results indicated that Ca(2+) concentrations at GV, GVBD, MI and MII stages were 78.06, 147.41, 126.97 and 97.73 nmol/l, respectively, and that 86.30% of oocytes remained at the GV stage and no oocyte developed to MII in Ca(2+)-free culture medium, and 1.1% of oocytes stayed at the GV stage and 83.5% of oocytes developed to MII in Ca(2+) culture medium. These results suggest that the occurrence of GVBD and cell cycle progression to MI and MII stages are closely related to Ca(2+), and that extracellular Ca(2+) performs a specific function for the initiation of meiotic resumption in caprine oocytes.

Impact of IL-1 receptor antagonist gene polymorphism on schizophrenia and bipolar disorder

OBJECTIVES

Variable levels of cytokines were observed in patients with schizophrenia and bipolar disorder, and an especially high level of interleukin-1 (IL-1) was detected in schizophrenia patients. It is known that IL-1 receptor antagonist (IL-1RA) binds to IL-1 receptors and inhibits the receptor binding of IL-1alpha and IL-1beta.

METHODS

In this study, the association between the variable number of tandem repeats polymorphism of the IL-1RA gene and schizophrenia (n=269) and bipolar disorder (n=83) was investigated.

RESULTS

The genotype distribution and allele frequency were significantly different between schizophrenic patients and the control group (P<0.05); however, there were no prominent differences between bipolar patients and the control group. The carriage rate for the IL1RN*2 allele was associated with higher risk of schizophrenia (odds ratio=2.24).

CONCLUSIONS

This study indicates that IL-1RA could be a candidate gene for susceptibility to schizophrenia.

Effects of Paeonia lactiflora root extracts on the secretions of monocyte chemotactic protein-1 and -3 in human nasal fibroblasts

In the field of Oriental medicine, the root of Paeonia lactiflora (Paeoniae Radix) has been prescribed usually to treat the common cold, and it was thought to alleviate upper respiratory infection or nasal inflammation. Monocyte chemotactic proteins (MCP)-1 and MCP-3 are known as the most potent chemokines to mediate allergic inflammation. The object of the study was to investigate the effect of Paeoniae Radix on the release of the chemokines such as MCP-1 and MCP-3. To detect the secretion of MCPs, an enzyme-linked immunosorbent assay was performed for human nasal mucosal fibroblasts after stimulation with several cytokines such as tumor necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma) and interleukin-1beta (IL-1beta). The secretion of MCP-1 was increased after stimulation with TNF-alpha or IL-1beta treatment. Co-treatment of TNF-alpha and IFN-gamma, or IL-1beta and IFN-gamma increased the secretion of MCP-1 and MCP-3. Paeoniae Radix was tested with inflammatory cytokines, and the results showed that the Paeoniae Radix significantly decreased the secretion of MCP-1 and MCP-3. In our study, Paeoniae Radix may play an important role in nasal inflammation with a modulation of MCP-1 and MCP-3.

Large bowel obstruction caused by sclerosing peritonitis: contrast-enhanced CT findings

Sclerosing peritonitis (SP) is a rare but serious complication of chronic ambulatory peritoneal dialysis (CAPD). SP is characterized by thickening of the peritoneum that encloses some or all of the small intestine. However, the early clinical features of SP are non-specific and are often not recognized until the patient develops complications. The most common complications of SP appear to be partial or complete small bowel obstruction, small bowel necrosis, and enterocutaneous fistulae, all of which, necessitate surgical intervention and have high mortality rates. Although the CT findings of SP are well recognized, to our knowledge, large bowel obstruction due to SP without peritoneal change have not been reported. We report a case of large bowel obstruction due to peritoneal sclerosis following long-term CAPD.

Microsatellite instability is absent in liver and biliary mucosa of patients with primary sclerosing cholangitis

Microsatellite instability occurs in the colonic mucosa of patients with inflammatory bowel disease and may predispose the mucosa to neoplastic transformation. It is unknown whether microsatellite instability also plays a role in the neoplastic risk associated with primary sclerosing cholangitis. We examined 134 tissue samples from 21 patients with sclerosing cholangitis for microsatellite instability at eight loci. All tissues were also stained immunohistochemically using an antibody to the proliferation marker Ki-67. Microsatellite instability did not occur in any samples from the intrahepatic or extrahepatic biliary system, although one patient demonstrated instability in the colon. Ki-67 indices ranged from 0 to 2.5 in nondysplastic biliary epithelium and from 1.5 to 29.4 in areas of dysplasia. The absence of microsatellite instability in sclerosing cholangitis suggests that the genetic basis of neoplastic progression in chronic inflammatory disease of the bile ducts differs from that of intestinal cancers arising in the setting of chronic inflammatory bowel disease and may relate to differences in the microenvironment in these two sites.

A case of bronchiolitis obliterans organizing pneumonia associated with adenovirus

A 58-year-old man described a short history of dyspnea and a preceding flu like illness with roentgenographic features of an interstitial lung disease. An open lung biopsy specimen from him showed bronchiolitis obliterans with organizing pneumonia (BOOP). Adenovirus was isolated from a throat swab. There was both clinical and radiographic improvement with supportive care. We herein report a first case of BOOP associated with adenovirus in Korea.

Nonspecific interstitial pneumonia/fibrosis: clinical manifestations, histologic and radiologic features

OBJECTIVES

Customarily used classification of IPF did not satisfy a sizable group of patients with IPF that in the past had been lumped with UIP and now currently has begun to be recognized as nonspecific interstitial pneumonia/fibrosis (NIP). There are few reports about the clinical features of NIP.

METHODS

The pathologic slides of 66 patients having open lung biopsy (OLB) for the differential diagnosis of interstitial lung diseases (ILD) from 1984 to 1995 were reviewed. Seven cases were confirmed as NIP. The clinical record, pulmonary function tests (PFT), chest PA and HRCT were reviewed and analysed retrospectively.

RESULTS

Six patients with NIP were female. The median age was 56 years. Mean duration of symptoms was 4 months. Five patients had systemic flu-like symptoms, the most common respiratory symptom was gradual dyspnea. Two patients revealed a mild degree of anemia. Four cases had leukocytois of more than 10,000/mm3. ESR and CRP O.K. elevated in all measured cases. Anti-nuclear antibody (ANA) was positive in three of six patients and ds-DNA antibody was positive in one of six patients. Restrictive pattern of PFT was predominant. Diffusion capacity of carbon monoxide (DLCO) decreased markedly. In bronchoalveolar lavage (BAL), total cell counts elevated about three times of normal value. On differential counts of BAL cells, lymphocytes, neutrophils and eosinophils were higher than those of normal controls. The prominent finding of chest radiology was bilaterally patchy opacifications in parenchyme of lower lung zones. On HRCT, bilaterally patchy areas of ground-glass attenuation and/or areas of alveolar consolidation were commonly shown. The number of pathologic type was one case of group I, four cases of group II and two cases of group III. The average period from diagnosis to the last follow-up was 24.8 months. Five patients were clinically recovered to the previously well-being state.

CONCLUSION

Patients with NIP had different clinical features from UIP, AIP and DIP. They also had characteristic findings of radiology and their prognosis seems to be better than UIP.

A case of disseminated coccidioidomycosis--autopsy report

Disseminated coccidioidomycosis is a systemic fungal infection that is occurring more commonly and causes high mortality in patients with compromised host defense or debilitated. It is endemic in certain areas of North, Central, and South America. Increasingly, cases are being recognized outside the endemic area, due to travelers who have visited an endemic area. We experienced a case of disseminated coccidioidomycosis, as a reactivation of infection acquired earlier in a patient, who was a former resident of an endemic area.

Clinical features of interstitial lung diseases

OBJECTIVES

Interstitial lung diseases (ILD) are heterogeneous groups of disorders that involve the interstitium of the lung. Lung biopsy is mandatory in most cases of ILD for diagnosis. In Korea, a few clinical data about ILD were analyzed on the basis of pathologic proof. Thus, we analysed the clinical profiles of patients with ILD who had lung biopsy in a tertiary university hospital.

METHODS

Clinical and pathologic data concerning 100 patients who had open lung biopsy (OLB) and/or transbronchial lung biopsy (TBLB) were prospectively analysed. Two patients were excluded because one patient was proven to have metastatic cancer and the other to have miliary tuberculosis. One patient had two combined diseases: rheumatoid arthritis and pneumoconiosis. Thus, 99 cases were analysed from 98 patients. Demographic characteristics, pulmonary functions and pathologic findings were analysed according to the disease entities of ILD. Pathologic findings were classified only in patients who had OLB. Clinical courses were also analysed during follow-up.

RESULTS

OLB was performed on 68 cases with concomittant TBLB in 18 cases and 30 cases had TBLB only. Mediastinal lymph node biopsy has performed on one case. The most common cause of ILD was IPF (51.5%), which was followed by CVD.PF (15.2%) and HP (9.1%). Average age of 51 cases with idiopathic pulmonary fibrosis (IPF) was 60 +/- 11 years, that of 15 cases with collagen vascular disease associated pulmonary fibrosis (CVD-PF) was 46 +/- 17 years and that of 9 cases with hypersensitivity pneumonitis (HP) was 53 +/- 8.1 years. In IPF, CVD-PF AND HP, male to female ratio was equal. But female was dominant in sarcoidosis and male was dominant in pneumoconiosis. Pulmonary function tests (PFT) in IPF, CVD-PF and HP were restrictive patterns in half of the cases. In pneumoconiosis and sarcoidosis, PFT showed normal pattern. Usual interstitial pneumonia (UIP) was the most common pathologic type in IPF and CVD-PF. The most common cause of CVD-PF was rheumatoid arthritis. The overall mortality rate was 12.1%.

CONCLUSION

We reported that the ILD had a variety of disease entities and pathologic types even in one tertiary referral hospital. We hope that a multi-center study will be performed on the basis of pathologic proof in the future.

In situ detection of hepatitis C virus RNA in liver tissue using a digoxigenin-labeled probe created during a polymerase chain reaction

The cellular localization of hepatitis C virus (HCV) RNA in liver tissue was studied by nonisotopic in situ hybridization using a digoxigenin-labeled cDNA probe created during a polymerase chain reaction on samples from 16 patients with chronic HCV infection. Hybridization signals were recognized in the cytoplasm of the hepatocytes, and a few hepatocytes had hybridization signals in the nucleus as well. HCV RNA positive hepatocytes were found in 1 of 9 patients with chronic persistent hepatitis, 2 of 5 patients with chronic active hepatitis, and in each of 2 patients with chronic active hepatitis and cirrhosis. Positive signals were found in many hepatocytes within the lobule in liver sections of patients with advanced chronic active hepatitis. A number of HCV RNA positive hepatocytes were found in nodules, but not in the area of fibrosis. On the other hand, positive signals were found in a few hepatocytes scattered in the lobule in a patient with chronic persistent hepatitis. The mean ALT levels in the patients with positive signal (175.6 +/- 44.2 U/L) were significantly higher than in those without a signal (70.27 +/- 16.1 U/L) (P < 0.05). The findings suggest that a larger amount of HCV may be present during the advanced than during the early stages of type C hepatitis and nonisotopic in situ hybridization using a digoxigenin-labeled HCV cDNA probe created during a polymerase chain reaction deserves wider application for the detection of HCV replication in specimens.

A case of amiodarone-associated pulmonary toxicity

Amiodarone is an iodinated benzofuran derivative that represents a new and extremely effective therapy for certain life-threatening refractory cardiac arrgythmia. There are numerous side effects associated with amiodarone therapy, including corneal microdeposits. Skin reactions and others. Pulmonary toxicity, however, represents the most serious adverse reaction limiting the clinical effecacy of this antidysrhythmic drug. Recently, we experienced a case of amiodarone-induced pulmonary toxicity confirmed by open lung biopsy with light-and electron-microscopy. So, we report a case of amiodarone-induced pulmonary toxicity with a literature review.

Imported CNS schistosomiasis--a case report

Central nervous system (CNS) involvement may occur in chronic schistosomiasis. It can be produced by any Schistosome species but happens most frequently in chronic Schistosoma japonicum infection. CNS involvement by S. mansoni is relatively rare but it may occur by embolization of eggs or ectopic migration of adult worms. A case of cerebral schistosomiasis caused by S. mansoni in a 40-year-old man, who had worked in Yemen, is reported. Biopsies taken from the cerebellar vermis and the roof of the fourth ventricle, showed granulomatous inflammation due to eggs. S. mansoni was identified by stool examination and ELISA using serum and CSF. This is the first imported case of cerebral schistosomiasis in Korea.

Pulmonary embolism as the initial manifestation of large cell lung cancer--a case report with review

Lung cancer is known as a risk factor of pulmonary embolism. We experienced a case of pulmonary embolism combined with pleural effusion and pleuritic chest pain as the initial manifestation of large cell lung cancer, which is a relatively rare cell type of lung cancer in Korea. We report it with a review of the literature.

Rapid diagnosis of Campylobacter pylori infection by urea test paper

Antral biopsy specimens from 106 patients were examined by culture, Gram stain and silver stain for Campylobacter pylori. Biopsies were also examined by a urea test paper test (UTPT). Of 106 patients studied C. pylori was detected in 68 (64.2%) by Gram stain, silver stain and culture. The UTPT was positive in 63 (59.4%) specimens. Five had false negative results using the UTPT with no false positive subjects. Thus, UTPT has a sensitivity of 92.6% (63/68) and a specificity of 100%. Of the 63 specimens that were UTPT positive, 45 were positive within 1 min, 58 were positive within 5 min. The remainder became positive between 5 and 15 min. There was a negative correlation between the time required for positive UTPT and the number of C. pylori per pit as seen on silver stained sections (P less than 0.05). UTPT is a rapid and sensitive method for detecting C. pylori in gastric mucosa. This enables early therapy, if indicated, before discharge from hospital. Moreover, the urea test paper method is cheap and easily stored.

The effect of sodium cromoglycate on the induction of experimental IgA nephropathy

Mesangial IgA nephropathy was experimentally induced in ddY mice by oral and parenteral administration of the poliomyelitis vaccine (POLIO), and we then tried to investigate if IgA deposition could be prevented by the concurrent use of sodium cromoglycate (SCG), which is known to inhibit the local mucosal immune reaction. Mucosal and systemic immunity could be induced by the administration of POLIO; proteinuria, increased serum IgA levels, mesangial cell proliferation, mesangial matrix widening, mesangial deposits of IgA, and large electron dense deposits in the mesangium were observed. Concurrent administration of SCG and POLIO resulted in a significant decrease in the serum IgA level and mesangial IgA deposits. The later addition or abstinence of SCG after the 70th day did not influence the glomerular mesangial IgA deposition. But the serum IgA level was still decreased by the continuous treatment of SCG even after the 70th day. Thus, mesangial IgA nephropathy simulating IgA nephropathy in humans could be induced in ddY mice using POLIO and its induction could largely be prevented by the concurrent use of SCG. However mesangial IgA deposits already present could not be cleared by the late administration of SCG.

Hepatoma presenting as extrahepatic biliary obstruction due to hemobilia

A case of hepatoma presenting as extrahepatic biliary obstruction due to hemobilia is reported. The patient, a 49-year-old woman, developed jaundice of the obstructive type after a history of B-viral hepatitis. On laparotomy, the liver revealed macronodular cirrhosis without any noticeable mass. A 4-cm sized friable tissue and blood clots were identified within the distended left hepatic duct. Pathologic examination of this tissue confirmed the diagnosis of hepatocellular carcinoma extended in the hepatic duct.