SUMS OF DUAL TOEPLITZ PRODUCTS ON THE ORTHOGONAL COMPLEMENTS OF FOCK-SOBOLEV SPACES

We consider dual Toeplitz operators on the orthogonal complements of the FockSobolev spaces of all nonnegative real orders.First,for symbols in a certain class containing all bounded functions,we study the problem of when an operator which is finite sums of the dual Toeplitz products is compact or zero.Next,for bounded symbols,we construct a symbol map and exhibit a short exact sequence associated with the C^(*)-algebra generated by all dual Toeplitz operators with bounded symbols.

Nationwide Trends in the Prevalence of Cigarette and E-cigarette Smoking among Korean Adults between 2014-2021:A Representative Serial Study of 1.2 Million Individuals

Both cigarette and e-cigarette use cause respiratory tract damage and related health outcomes,and potentially increase the risk of coronavirus disease 2019(COVID-19)-related symptoms[1].Since the COVID-19 pandemic,local and central governments have legally mandated wearing masks indoors and outdoors[2].

Pseudomembranous conjunctivitis in a patient with DRESS syndrome

Dear Editor,Drug rash with eosinophilia and systemic symptoms(DRESS)syndrome is a drug reaction featuring high fever,eosinophilia,skin rashes,and multi-organ involvement that may be fatal.Ocular manifestations,including cicatrizing conjunctivitis,corneal infiltration,and anterior uveitis,are rarely reported[1-6]but may cause serious complications if untreated.Therefore,it is important to diagnose DRESS syndrome in patients with ocular features promptly with appropriate treatment.This article reports a case diagnosed with DRESS syndrome associated with pseudomembranous conjunctivitis secondary to carfilzomib.

Genomic change in hepatitis B virus associated with development of hepatocellular carcinoma

AIM: To determine the genomic changes in hepatitis B virus(HBV) and evaluate their role in the development of hepatocellular carcinoma(HCC) in patients chronically infected with genotype C HBV.METHODS: Two hundred and forty chronic hepatitis B(CHB) patients were subjected and followed for a median of 105 mo. HCC was diagnosed in accordance with AASLD guidelines. The whole X, S, basal core promoter(BCP), and precore regions of HBV were sequenced using the direct sequencing method.RESULTS: All of the subjects were infected with genotype C HBV. Out of 240 CHB patients, 25(10%) had C1653 T and 33(14%) had T1753 V mutation in X region; 157(65%) had A1762T/G1764 A mutations in BCP region, 50(21%) had G1896 A mutation in precore region and 67(28%) had pre-S deletions. HCC occurred in 6 patients(3%). The prevalence of T1753 V mutation was significantly higher in patients who developed HCC than in those without HCC. The cumulative occurrence rates of HCC were 5% and 19% at 10 and 15 years, respectively, in patients with T1753 V mutant, which were significantly higher than 1% and 1% in those with wild type HBV(P < 0.001).CONCLUSION: The presence of T1753 V mutation in HBV X-gene significantly increases the risk of HCC development in patients chronically infected with genotype C HBV.

Effect of hyperthermia on calbindin-D 28k immunoreactivity in the hippocampal formation following transient global cerebral ischemia in gerbils

Calbindin D-28K （CB）, a Ca2＋-binding protein, maintains Ca2＋ homeostasis and protects neurons against various insults. Hyperthermia can exacerbate brain damage produced by ischemic insults. However, little is reported about the role of CB in the brain under hyperthermic condition during ischemic insults. We inves- tigated the effects of transient global cerebral ischemia on CB immunoreactivity as well as neuronal damage in the hippocampal formation under hyperthermic condition using immunohistochemistry for neuronal nuclei （NeuN） and CB, and Fluoro-Jade B histofluorescence staining in gerbils. Hyperthermia （39.5 ＋ 0.2~C） was induced for 30 minutes before and during transient ischemia. Hyperthermic ischemia resulted in neu- ronal damage/death in the pyramidal layer of CA1-3 area and in the polymorphic layer of the dentate gyrus at 1, 2, 5 days after ischemia. In addition, hyperthermic ischemia significantly decreaced CB immunoreac- tivity in damaged or dying neurons at 1, 2, 5 days after ischemia. In brief, hyperthermic condition produced more extensive and severer neuronal damage/death, and reduced CB immunoreactivity in the hippocampus following transient global cerebral ischemia. Present findings indicate that the degree of reduced CB immu- noreactivity might be related with various neuronal damage/death overtime and corresponding areas after ischemic insults.

Cryptogenic organizing pneumonia associated with pregnancy:A case report

BACKGROUND Cryptogenic organizing pneumonia(COP),formerly known as bronchiolitis obliterans organizing pneumonia,is an extremely rare disease in pregnancy.In this case,we report on COP diagnosed in recurrent pneumonia that does not respond to antibiotics in pregnant woman.CASE SUMMARY A 35-year-old woman with no prior lung disease presented with concerns of chest pain with cough,sputum,dyspnea,and mild fever at 11 wk’gestation.She was diagnosed with community-acquired pneumonia and treated with antibiotics;her symptoms improved temporarily.Four weeks after discharge,she was readmitted with aggravated symptoms.Chest computed tomography demonstrated multifocal patchy airspace consolidation and ground-glass opacities at the basal segments of the right lower lobe,at the lateral basal segment of the lower lobe,and at the lingular segment of the left upper lobe.Bronchoalveolar lavage revealed an increased lymphocyte count and a decreased CD4/CD8 ratio.Prednisolone(0.5 mg/kg/d)was administered for 10 d after the second admission.Dyspnea improved after 3 d of steroid treatment and other symptoms improved on the 5th day of steroid administration.Post-delivery transbronchial lung biopsy further revealed the presence of granulation tissue with fibroblasts in smallbronchiole lumens.CONCLUSION This case suggests that it is important to differentiate COP from atypical pneumonia in the deteriorated condition despite antibiotic treatment.

Neuronal injury and tumor necrosis factor-alpha immunoreactivity in the rat hippocampus in the early period of asphyxia-induced cardiac arrest under normothermia

Low survival rate occurs in patients who initially experience a spontaneous return of circulation after cardiac arrest（CA）. In this study, we induced asphyxial CA in adult male Sprague-Daley rats, maintained their body temperature at 37 ± 0.5°C, and then observed the survival rate during the post-resuscitation phase. We examined neuronal damage in the hippocampus using cresyl violet（CV） and Fluore-Jade B（F-J B） staining, and pro-inflammatory response using ionized calcium-binding adapter molecule 1（Iba-1）, glial fibrillary acidic protein（GFAP）, and tumor necrosis factor-alpha（TNF-α） immunohistochemistry in the hippocampus after asphyxial CA in rats under normothermia. Our results show that the survival rate decreased gradually post-CA（about 63% at 6 hours, 37% at 1 day, and 8% at 2 days post-CA）. Rats were sacrificed at these points in time post-CA, and no neuronal damage was found in the hippocampus until 1 day post-CA. However, some neurons in the stratum pyramidale of the CA region in the hippocampus were dead 2 days post-CA. Iba-1 immunoreactive microglia in the CA1 region did not change until 1 day postCA, and they were activated（enlarged cell bodies with short and thicken processes） in all layers 2 days postCA. Meanwhile, GFAP-immunoreactive astrocytes did not change significantly until 2 days post-CA. TNF-α immunoreactivity decreased significantly in neurons of the stratum pyramidale in the CA1 region 6 hours post-CA, decreased gradually until 1 day post-CA, and increased significantly again 2 days post-CA. These findings suggest that low survival rate of normothermic rats in the early period of asphyxia-induced CA is related to increased TNF-α immunoreactivity, but not to neuronal damage in the hippocampal CA1 region.

人参对大鼠血浆中乙醇浓度的影响

用被乙醇处置过的雄性费歇尔344大鼠来研究红参提取物对乙醇代谢的影响。给大鼠口服水溶性人参(200mg/kg),对照组给予同等剂量的水,随即用50％的乙醇给大鼠口服(3.2g/kg)或腹腔注射(1.5g/kg)。在给药前和给药后0.5、1、2、3、4和5小时分别从大鼠尾部动脉抽取一定量血液,测得一定的数值,绘制成血浆浓度—时间曲线(0-5小时)。发现,对于经口给予乙醇的大鼠来说,口服人参组血浆中乙醇的浓度——时间曲线下的平均面积比水对照组减少21.0％,而对于腹腔注射乙醇的大鼠来说,人参组与水对照组的乙醇浓度——时间曲线下的面积无显著区别。说明,大鼠血浆中乙醇浓度在口服乙醇的同时加用人参将比单独口服乙醇要低。而口服人参对经腹腔注射乙醇的大鼠来说,其血浆中乙醇的浓度不受影响。

SEQUENCES OF POWERS OF TOEPLITZ OPERATORS ON THE BERGMAN SPACE

We consider Toeplitz operators Tu with symbol u on the Bergman space of the unit ball,and then study the convergences and summability for the sequences of powers of Toeplitz operators.We first charactreize analytic symbolsφfor which the sequence Tφ*kf or Tφkf converges to 0 or∞as k→∞in norm for every nonzero Bergman function f.Also,we characterize analytic symbolsφfor which the norm of such a sequence is summable or not summable.We also study the corresponding problems on an infinite direct sum of Bergman spaces as a generalization of our result.

Estimated prevalence and trends in smoking among adolescents in South Korea,2005-2021:a nationwide serial study

Background Although smoking is classified as a risk factor for severe COVID-19 outcomes,there is a scarcity of studies on prevalence of smoking during the COVID-19 pandemic.Thus,this study aims to analyze the trends of prevalence of smoking in adolescents over the COVID-19 pandemic period.Methods The present study used data from middle to high school adolescents between 2005 and 2021 who participated in the Korea Youth Risk Behavior Web-based Survey(KYRBS).We evaluated the smoking prevalence(ever or daily)by year groups and estimated the slope in smoking prevalence before and during the pandemic.Results A total of 1,137,823 adolescents participated in the study[mean age,15.04 years[95%confidence interval(CI)15.03-15.06];and male,52.4%(95%CI 51.7-53.1)].The prevalence of ever smokers was 27.7%(95%CI 27.3-28.1)between 2005 and 2008 but decreased to 9.8%(95%CI 9.3-10.3)in 2021.A consistent trend was found in daily smokers,as the estimates decreased from 5.4%(95%CI 5.2-5.6)between 2005 and 2008 to 2.3%(95%CI 2.1-2.5)in 2021.However,the downward slope in the overall prevalence of ever smokers and daily smokers became less pronounced in the COVID-19 pandemic period than in the pre-pandemic period.In the subgroup with substance use,the decreasing slope in daily smokers was significantly more pronounced during the pandemic than during the pre-pandemic period.Conclusions The proportion of ever smokers and daily smokers showed a less pronounced decreasing trend during the pandemic.The findings of our study provide an overall understanding of the pandemic's impact on smoking prevalence in adolescents.

Pretreated Glehnia littoralis Extract Prevents Neuronal Death Following Transient Global Cerebral Ischemia through Increases of Superoxide Dismutase 1 and Brain-derived Neurotrophic Factor Expressions in the Gerbil Hippocampal Cornu Ammonis 1 Area

Background：Glehnia littoralis,as a traditional herbal medicine to heal various health ailments in East Asia,displays various therapeutic properties including antioxidant effects.However,neuroprotective effects of G.littoralis against cerebral ischemic insults have not yet been addressed.Therefore,in this study,we first examined its neuroprotective effects in the hippocampus using a gerbil model of transient global cerebral ischemia （TGCI）.Methods：Gerbils were subjected to TGCI for 5 min.G.littoralis extract （GLE;100 and 200 mg/kg） was administrated orally once daily for 7 days before ischemic surgery.Neuroprotection was examined by neuronal nuclear antigen immunohistochemistry and Fluoro-Jade B histofluorescence staining.Gliosis was observed by immunohistochemistry for glial fibrillary acidic protein and ionized calcium-binding adapter molecule 1.For neuroprotective mechanisms,immunohistochemistry for superoxide dismutase （SOD） 1 and brain-derived neurotrophic factor （BDNF） was done.Results：Pretreatment with 200 mg/kg of GLE protected pyramidal neurons in the cornu ammonis 1 （CA1） area from ischemic insult area （F=29.770,P 〈 0.05） and significantly inhibited activationsof astrocytes （F =22.959,P 〈 0.05） and microglia （F =44.135,P 〈 0.05） in the ischemic CA1 area.In addition,pretreatment with GLE significantly increased expressions of SOD1 （F =28.561,P 〈 0.05） and BDNF （F =55.298,P 〈 0.05） in CA1 pyramidal neurons of the sham-and ischemia-operated groups.Conclusions：Our findings indicate that pretreatment with GLE can protect neurons from ischemic insults,and we suggest that its neuroprotective mechanism may be closely associated with increases of SOD 1 and BDNF expressions as well as attenuation ofglial activation.

Sigmoid-sigmoid colon fistula caused by diverticulitis

To the Editor:Diverticular disease is common worldwide and the incidence of this disease increases with aging.Complicated diverticulitis is serious and includes abscess,fistula,obstruction,and peritonitis.Eventually,surgical treatment is recommended to the patients with symptomatic complications.Among these,colocolic fistula caused by diverticulitis is rare findings and especially,sigmoid-sigmoid fistula is an extremely rare complication.The present report describes a case of sigmoid-sigmoid colon fistula caused by diverticulitis.The results of this case may help physicians to recognize that multidisciplinary management and surgery are needed for the treatment of complicated diverticulitis with fistula.