[The ninth edition of TNM staging for lung cancer: precise staging for precise diagnosis and treatment]

The ninth edition of TNM staging for lung cancer has been announced at the 2023 World Lung Cancer Congress and implemented from January 1, 2024. Te focus of the ninth TNM staging change is dividing N2 into N2a and N2b, as well as M1c into M1c1 and M1c2. Although the T staging has not changed, it has played an important role in verifying the eighth edition of the T staging. The subdivision of stage N2 has led some patients with ⅢA of the eighth edition to experience ascending or descending stages, which will more accurately help to assess the condition and prognosis of patients with mediastinal lymph node metastasis, as well as the design of related clinical studies. Modifying the M1c staging will help define oligometastasis and explore new treatment models in the future. The ninth edition of the TNM staging system provides a more detailed division of different tumor loads, but there is no clear explanation for the staging of lung cancer after neoadjuvant therapy. Further data analysis is needed, and it is expected to be answered in the tenth edition of TNM staging.

Abstract 3415: Preclinical characterization of a brain penetrant RAF inhibitor, BDTX-4933, targeting oncogenic BRAF Class I/II/III and RAS mutations

Mutations in BRAF and RAS are often oncogenic and lead to a constitutively active MAPK pathway that promotes aberrant cell proliferation and tumor growth. Currently approved BRAF inhibitors are selective against monomeric BRAF V600 mutants. These drugs are largely inactive against non-V600 dimeric BRAF mutants and have poor brain penetration. Although there is an FDA-approved KRAS G12C mutant-selective inhibitor, there are no approved inhibitors for cancer patients who harbor other (non-G12C) KRAS and NRAS mutations which promote tumor growth likely through constitutively active RAF dimers. There remains a high unmet clinical need for a highly CNS penetrant oral RAF inhibitor that targets a broad spectrum of BRAF mutations and constitutively active RAF dimers without paradoxical activation of the MAPK signaling pathway. BDTX-4933 is a potent, reversible, CNS penetrant RAF MasterKey inhibitor designed to target a large family of oncogenic BRAF mutations including BRAF monomers and RAF dimers. The compound inhibits not only all classes (I, II, and III) of BRAF mutations but also targets constitutively active RAF dimers promoted by upstream oncogenic MAPK pathway alterations, such as RAS mutations. In a panel of cancer cell lines that endogenously express BRAF or RAS mutations, BDTX-4933 demonstrates inhibition of the MAPK pathway signaling without paradoxical activation, resulting in potent inhibition of cellular proliferation. BDTX-4933 shows target engagement, inhibiting ERK phosphorylation, in tumor models in vivo, achieving strong anti-tumor efficacy and tumor regression across tumor models driven by either BRAF or RAS mutations. Furthermore, BDTX-4933 exhibits high CNS exposure leading to dose-dependent tumor growth inhibition, and survival benefit in mice implanted intracranially with xenograft BRAF mutant tumors. BDTX-4933 has a best-in-class profile to treat cancer patients harboring BRAF mutations or RAF dimer-promoting upstream genetic alterations. IND-enabling studies for BDTX-4933 are on-going.

Citation Format: Yoon-Chi Han, Pui-Yee Ng, Luisa Shin Ogawa, Shao Ning Yang, Miao Chen, Noboru Ishiyama, Tai-An Lin, Elizabeth Buck. Preclinical characterization of a brain penetrant RAF inhibitor, BDTX-4933, targeting oncogenic BRAF Class I/II/III and RAS mutations [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3415.

[Gene mutation profiles and clinicopathological features of patients with non-small cell lung cancer harboring KRAS G12C mutation: a single-center retrospective study]

Objective: To accurately screen non-small cell lung cancer (NSCLC) patients with KRAS G12C mutation and to evaluate their clinicopathological features, prognostic factors and current treatment status. Methods: A total of 19 410 NSCLC cases diagnosed at the Department of Pathology of Shanghai Chest Hospital, Shanghai, China from January 2018 to September 2021 were retrospectively reviewed, and the cases with KRAS gene mutation detected by next-generation sequencing were included. The clinicopathological and genetic mutation data of these cases were collected and analyzed. Results: A total of 1 633 (8.4%) NSCLC patients carried a KRAS gene mutation, among whom G12C was the most frequent (468 cases, 28.7%) mutant subtype. The mutation was more commonly found in males (414/468, 88.5%), patients with a history of smoking (308/468, 65.8%), and patients with a pathological type of invasive adenocarcinoma (231/468, 49.4%). The most common co-mutated genes in KRAS G12C mutant NSCLC were TP53 (52.4%, 245/468), STK11 (18.6%, 87/468) and ATM (13.2%, 62/468). The proportion of PD-L1 expression (≥1%) in KRAS G12C mutant NSCLC was significantly higher than that in patients without G12C mutation [64.3% (90/140) vs. 56.1% (193/344), P=0.014]. Immune checkpoint inhibitors (ICIs) treatment significantly prolonged progression-free survival (PFS) in NSCLC patients (10.0 months vs. 5.0 months, P=0.011). However, combination of chemotherapy and ICIs with anti-angiogenesis inhibitors or multi-target inhibitors did not significantly improve PFS in patients with KRAS G12C mutant NSCLC (P>0.05). Patients with KRAS G12C mutation NSCLC treated with ICIs and KRAS G12C patients with TP53 mutation had significantly longer median PFS than those with STK11 mutation (9.0 months vs. 4.3 months, P=0.012). Conclusions: Patients with KRAS G12C mutant NSCLC have relatively higher levels of PD-L1 expression and can benefit from ICIs treatment. The feasibility of chemotherapy, ICIs therapy and their combination needs further investigation.

[Diagnosis and treatment strategies of 56 cases of middle ear myoclonus]

Objective: To analyze the clinical characteristics and treatment of middle ear myoclonus. Methods: Fifty-six cases of middle ear myoclonus were enrolled in Shandong Provincial ENT Hospital, Shandong University from September 2019 to August 2021, including 23 males and 33 females. The age ranged from 6 to 75 years, with a median age of 35 years; Forty-seven cases were unilateral tinnitus, nine cases were bilateral tinnitus. The time of tinnitus ranged from 20 days to 8 years. The voice characteristics, inducing factors, nature (frequency) of tinnitus, tympanic membrane conditions during tinnitus, audiological related tests, including long-term acoustic tympanogram, stapedius acoustic reflex, pure tone auditory threshold, short increment sensitivity test, alternate binaural loudness balance test, loudness discomfort threshold, vestibular function examination, facial electromyography, and imaging examination were recorded. Oral carbamazepine and/or surgical treatment were used. The patients were followed up for 6-24 months and the tinnitus changes were observed. Results: Tinnitus was diverse, including stepping on snow liking sound, rhythmic drumming, white noise, and so on. The inducing factors included external sound, body position change, touching the skin around the face and ears, speaking, chewing and blinking, etc. Forty-four cases were induced by single factor and 9 cases were induced by two or more factors. There was no definite inducing factor in 1 case. One patient had tinnitus with epilepsy. One case of traumatic facial paralysis after facial nerve decompression could induce tinnitus on the affected side when the auricle moved. Tympanic membrane flutter with the same frequency as tinnitus was found in 12 cases by otoscopy, and the waveform with the same frequency as tinnitus was found by long-term tympanogram examination. There were 7 patients with no tympanic membrane activity by otoscopy, the 7 cases also with the same frequency of tinnitus by long-term tympanogram examination, but the change rate of the waveform was faster than that of the patients with tympanic membrane flutter. All patients with tinnitus had no change in hearing. One case of tinnitus complicated with epilepsy (a 6-year-old child) was treated with antiepileptic drug (topiramate) and tinnitus subsided. One case suffered from tinnitus after facial nerve decompression for traumatic facial paralysis was not given special treatment. Fifty-four cases were treated with oral drug (carbamazepine), of which 10 cases were completely controlled and 23 cases were relieved; 21 cases were invalid. Among the 21 patients with no effect of carbamazepine treatment, 8 patients were treated by surgery, 7 patients had no tinnitus after surgery, 1 patient received three times of operation, and the third operation was followed up for 6 months, no tinnitus occurred again. The other 13 cases refused the surgical treatment due to personal reasons. Conclusions: Middle ear myoclonus tinnitus and the inducing factors manifestate diversity. Oral carbamazepine and other sedative drugs are effective for some patients, and surgical treatment is feasible for those who are ineffective for medication.

[The surgical management of benign tumors of the lateral skull base with intracranial invasion: experience from a single centre over ten years]

Objective: To investigate the clinical features, pathological types, imaging features, and surgical strategies of lateral skull base benign tumors with intracranial invasion. Methods: From January 2011 to March 2021, 36 patients of lateral skull base benign tumors with intracranial invasion were included in this retrospective study. Among the 36 patients, 14 cases were male, 22 cases were female, the aged range from 20-67, with the median age of 48. The clinical manifestations, characteristic imaging findings, pathological types, surgical approach selection, and prognosis were analyzed. Results: 36 cases of lateral skull base tumors with intracranial invasion were all accepted surgeries. 23 cases were neurogenic tumors, facial nerve tumors (n=8), neurogenic tumors in jugular foramen with unknown origin(n=6), hypoglossal schwannoma (n=3), transotic intralabyrinthine schwannoma (n=3), vestibular schwannoma involving the middle ear(n=2), vagal nerve schwannoma(n=1). Other types of tumors included meningioma (n=10) and paraganglioma (Di 1 or 2,n=3). Different pathological types of tumors had different clinical manifestations and imaging manifestations. Sixteen cases were subjected to primary resection, while, other 20 cases underwent staged operation. Among the patients with staged operation, 10 patients had completed the second stage operation, five patients were waiting for the second stage operation, the other five patient's residual intracranial tumor were significantly reduced and the space between tumor and brain tissues widened after the first stage operation, so, the following up with "wait and scan"policy was suggested. The total resection rate of tumors was related to the pathological nature, in which neurogenic tumors were 15/17, and meningiomas were 5/8. The main postoperative complications were cerebrospinal fluid leakage and infection in the operation area. There were two cases of postoperative intracranial infection, and three cases of cerebrospinal fluid leakage occurred in non staged operation cases. Conclusions: Lateral skull base tumors with intracranial invasion are rare. The most common pathological type is schwannoma, followed by meningioma and paraganglioma. For this type of tumor, if there is infection in the operation area and neck invasion is large, it is suggested to choose staged surgery, which can reduce the risk of intracranial infection and the incidence of cerebrospinal fluid leakage. Staged surgery strategy can also reduce the difficulty of second stage surgery, so the operation is much safer than non staged surgery.

Abstract P229: Pre-clinical evaluation of next-generation inhibitor targeting a wide spectrum of oncogenic BRAF dimers

The canonical BRAF V600E (Class I) mutation is a potent oncogene uniquely active as a RAS-independent monomer, successfully targeted by several FDA-approved inhibitors. However, these first-generation BRAF inhibitors are not active against non-canonical BRAF oncogenic mutations, including BRAF-fusions, that drive RAS-independent (Class II) or RAS-dependent (Class III) dimers. As such, developing inhibitors directed against dimeric BRAF oncogenic mutations that avoid paradoxical activation is a major unmet clinical need. We applied proprietary Mutation-Allostery-Pharmacology (MAP) platform technology developed by Black Diamond Therapeutics to identify and validate a group of previously uncharacterized non-canonical oncogenic Class II and Class III BRAF mutation clusters. We further demonstrate that this ensemble of novel and previously validated non-canonical oncogenic BRAF mutants can form the basis of a differentiated drug discovery program aimed at identifying small molecules that potently and selectively target this family of dimeric BRAF mutations. Herein, we describe a small molecule inhibitor, BDTX BRAF-A, with potent anti-proliferative activity directed against tumor cells expressing a wide spectrum of non-canonical Class II/III mutations. This broad activity (“MasterKey” profile) of BDTX BRAF-A is further demonstrated in cell lines that harbor endogenous oncogenic dimer-inducing BRAF mutations and in various solid tumor patient-derived xenograft (PDX) models ex vivo. Importantly, BDTX BRAF-A did not induce paradoxical RAF activation characteristic of Class I BRAF inhibitors. Finally, BDTX BRAF-A achieves robust anti-tumor efficacy and target engagement of dimeric BRAF oncogenes in mouse models. These data support the continued development of rationally designed molecules targeting a broad range of non-canonical BRAF dimer-promoting mutations to extend the prospect of precision medicine in patients.

Citation Format: Yoon-Chi Han, Pui Yee Ng, Ryan Schulz, Shao Ning Yang, Alana Lelo, Luisa Shin, Matthew O'Connor, Ivan Jewett, Noboru Ishiyama, Darlene Romashko, Shalabh Thakur, Andrei Salomatov, Sherri Smith, Elizabeth Buck, Christopher Roberts, Matthew Lucas, Tai-An Lin. Pre-clinical evaluation of next-generation inhibitor targeting a wide spectrum of oncogenic BRAF dimers [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2021 Oct 7-10. Philadelphia (PA): AACR; Mol Cancer Ther 2021;20(12 Suppl):Abstract nr P229.

Development of Highly Optimized Antibody-Drug Conjugates against CD33 and CD123 for Acute Myeloid Leukemia

PURPOSE

Mortality due to acute myeloid leukemia (AML) remains high, and the management of relapsed or refractory AML continues to be therapeutically challenging. The reapproval of Mylotarg, an anti-CD33-calicheamicin antibody-drug conjugate (ADC), has provided a proof of concept for an ADC-based therapeutic for AML. Several other ADCs have since entered clinical development of AML, but have met with limited success. We sought to develop a next-generation ADC for AML with a wide therapeutic index (TI) that overcomes the shortcomings of previous generations of ADCs.

EXPERIMENTAL DESIGN

We compared the TI of our novel CD33-targeted ADC platform with other currently available CD33-targeted ADCs in preclinical models of AML. Next, using this next-generation ADC platform, we performed a head-to-head comparison of two attractive AML antigens, CD33 and CD123.

RESULTS

Our novel ADC platform offered improved safety and TI when compared with certain currently available ADC platforms in preclinical models of AML. Differentiation between the CD33- and CD123-targeted ADCs was observed in safety studies conducted in cynomolgus monkeys. The CD33-targeted ADC produced severe hematologic toxicity, whereas minimal hematologic toxicity was observed with the CD123-targeted ADC at the same doses and exposures. The improved toxicity profile of an ADC targeting CD123 over CD33 was consistent with the more restricted expression of CD123 in normal tissues.

CONCLUSIONS

We optimized all components of ADC design (i.e., leukemia antigen, antibody, and linker-payload) to develop an ADC that has the potential to translate into an effective new therapy against AML.

Comparison of primary arthrodesis versus open reduction with internal fixation for Lisfranc injuries: Systematic review and meta-analysis

Objective

Multiple studies have compared primary arthrodesis versus open reduction with internal fixation (ORIF) for surgical treatment of fractures of the Lisfranc joint, but their results have been inconsistent. Therefore, the present systematic review and meta-analysis was performed to compare the clinical efficacy of arthrodesis versus ORIF for the treatment of Lisfranc injuries.

Methods

Through searching the Embase, PubMed, PMC, CINAHL, PQDT, and Cochrane Library databases (from July 1998 to July 2018), we identified five case-controlled trials and two randomized controlled trials that compared the clinical efficacy of primary arthrodesis and ORIF for treating Lisfranc injuries. The extracted data were analyzed using Review manager 5.3 software.

Results

Through comparisons of data for primary arthrodesis and ORIF groups, we found no significant differences in the anatomic reduction rate, revision surgery rate, and total rate of complications between the different treatment approaches. However, arthrodesis was associated with a significantly better American Orthopedic Foot and Ankle Society (AOFAS) score, return to duty rate, and visual analog scale score with a lower incidence of hardware removal compared with ORIF.

Conclusions

For the treatment for Lisfranc injuries, primary arthrodesis was superior to ORIF based on a higher AOFAS score, better return to duty rate, lower postoperative pain, and lower requirement for internal fixation removal. Further evidence from future randomized controlled trials with higher quality and larger sample sizes is needed to confirm these findings.

[Consistency of ALK Ventana-D5F3 immunohistochemistry interpretation in lung adenocarcinoma among Chinese histopathologists]

Objective: To understand the consistency of ALK Ventana-D5F3 immunohistochemistry (IHC) interpretation in Chinese lung adenocarcinoma among histopathologists from different hospitals, and to recommend solution for the problems found during the interpretation of ALK IHC in real world, with the aim of the precise selection of patients who can benefit from ALK targeted therapy. Methods: This was a multicenter and retrospective study. A total of 109 lung adenocarcinoma cases with ALK Ventana-D5F3 IHC staining were collected from 31 lung cancer centers in RATICAL research group from January to June in 2018. All cases were scanned into digital imaging with Ventana iSCANcoreo Digital Slide Scanning System and scored by 31 histopathologists from different centers according to ALK binary (positive or negative) interpretation based on its manufacturer's protocol. The cases with high inconsistency rate were further analyzed using FISH/RT-PCR/NGS. Results: There were 49 ALK positive cases and 60 ALK negative cases, confirmed by re-evaluation by the specialist panel. Two cases (No. 2302 and No.2701) scored as positive by local hospitals were rescored as negative, and were confirmed to be negative by RT-PCR/FISH/NGS. The false interpretation rate of these two cases was 58.1% (18/31) and 48.4% (15/31), respectively. Six out of 31 (19.4%) pathologists got 100% accuracy. The minimum consistency between every two pathologists was 75.8%.At least one pathologist gave negative judgement (false negative) or positive judgement (false positive) in the 49 positive or 60 negative cases, accounted for 26.5% (13/49), 41.7% (25/60), respectively, with at least one uncertainty interpretation accounted for 31.2% (34/109). Conclusion: There are certain heterogeneities and misclassifications in the real world interpretation of ALK-D5F3 IHC test, which need to be guided by the oncoming expert consensus based on the real world data.

[A cross-sectional study on the association between frailty and muscular performances in hospitalized elder patients with coronary artery disease]

Objective: To explore the association between frailty and muscle performances of hospitalized elder adults with coronary artery disease. Methods: A total of 122 hospitalized patients aged 65-85 years old with coronary artery disease from Department of Geriatrics and Cardiology, Peking Union Medical College Hospital between December 2017 and March 2018 were enrolled in the study. A comprehensive geriatric assessment was performed to evaluate existing comorbidity and geriatric syndromes of the patients. Frailty was assessed using the Clinical Fraity Scale. The patients were classified as frail and non-frail, according to the scale. Muscle performances were assessed using grip strength, gait speed, etc. Whole body and appendicular skeletal muscle mass was detected with bioelectrical impedance analysis in patients with reduced grip strength or slowed gait speed. Appendicular skeletal muscle index (ASMI) was calculated. Results: Among all subjects, 28 were with frailty (23.0%) and 94 were without (77.0%). The frail patients were older [(76.7±5.4) years vs. (72.2±5.6)years], had higher Charlson comorbidity index [2.0(1.0,2.75)vs. 1.0(0,2.0)], and higher proportion of malnutrition (14.29% vs. 1.06%), urinary incontinence (39.29% vs. 15.96%), using walking-aid (28.57% vs. 6.38%), and more kinds of taken drugs (8.1±3.0 vs. 6.6±2.7), than the non-frail patients. Prealbumin levels [(207.8±60.0)mg/L vs.(234.3±45.4)mg/L] were lower, and highly sensitive C-reactive protein levels [(5.89±9.57)mg/L vs.(1.89±2.49)mg/L] were higher in the frail patients than in the non-frail patients (all P<0.05). Compared with non-frail patients, the frail patients had poorer grip strength [(19.67±7)kg vs.(29.23±8.29)kg] and slower gait speed [(0.54±0.2)m/s vs.(0.91±0.22)m/s] (all P<0.001). Spearman rank correlation analyses showed that grip strength was positively correlated with the appendicular skeletal muscle mass(r=0.811), whole body skeletal muscle mass(r=0.74) and the ASMI (r=0.783), respectively. Conclusions: The incidence of frailty among hospitalized older adults with coronary artery disease is high. Poor muscle performances were common in these patients. Assessment of frailty and muscle performances can help to evaluate the overall function of older adults with cardiovascular disease in a comprehensive way.

[Primary biliary cholangitis and bile acid metabolism]

Primary biliary cholangitis (PBC) is an immune-mediated cholestatic liver disease of unknown pathogenesis. The research on immunologic injury in the past helps us to understand more about this disease, but there are still many problems and challenges in the research on PBC. With a focus on the cholestatic features of PBC, this article reviews the research advances in bile acid metabolism in the field of PBC, in order to provide new thoughts for future research.

Abstract 935: Generation and preclinical characterization of CD123-CPI antibody-drug conjugate (ADC)

CD123 is expressed on cancer cells in a variety of hematologic malignancies including acute myeloid leukemia (AML). CD123 is frequently expressed on leukemic blasts and leukemic stem cells (LSCs), a cell population associated with relapse in patients, but there is minimal or no expression on most normal hematopoietic cells and solid tissues. Thus, CD123 is a promising target for AML. We have generated an anti-CD123 ADC that carries cyclopropylpyrroloindoline (CPI) payload that crosslinks DNA. A drug loading of 2 molecules of CPI per molecule of antibody was achieved by site-specific conjugation using our transglutaminase methodology. Upon binding to the CD123 antigen, CD123-ADC is internalized and delivered to the endosomal-lysosomal pathway whereupon the CPI payload is released from the antibody by proteolysis of the linker. The released CPI alkylates DNA, which activates ATR/ATM, CHK1, CHK2 and FANCD2, ultimately resulting in cell death. In vitro, CD123–CPI elicited cytotoxicity in a dose-dependent manner against several CD123-positive, but not against CD123-negative cell lines. Cell lines with higher CD123 expression level were more sensitive to the ADC. Long-Term Culture-Initiating Cells in vitro assay showed that AML patient bone marrow samples that naturally have high percentage of LSCs yielded substantially fewer colonies in CD123-ADC treated cells compared to control ADC. Importantly, CD123-ADC had no adverse effects in healthy donor bone marrow cells experimentally enriched in CD34+ primitive stem cells. This result suggests that CD123-ADC specifically inhibits the growth potential of leukemic blasts and progenitor cells. In vivo, robust antileukemic activity was observed in CD123-positive AML cell line-derived xenograft models. Low doses of CD123-ADC effectively regressed tumors whereas the tumor progressed in mice that received control ADC. Efficacy was also evaluated in disseminated AML PDX models (n≥7) established with patient samples of various cytogenetics and molecular abnormalities, and relapse/refractory. Flow cytometry analyses of leukemic load in peripheral blood and in bone marrow samples of mice showed that CD123-ADC was efficacious in reducing tumor burden even at the suboptimal doses. In summary, our data demonstrate that our CD123-ADC is highly active in a broad panel of primary AML samples. Currently, CD123-ADC in combination with other AML therapies is being tested in vivo. All these attributes of CD123-ADC make it an attractive agent to evaluate in clinical trials.

Citation Format: Yoon-Chi Han, Fan Jiang, Nicole Piche-Nicholas, Madan Katragadda, Nadira Prashad, Manoj Charati, Wendy Hu, Mauricio Leal, Nathan Tumey, Andreas Maderna, Russell Dushin, Kenny Kim, LuAnna Lemon, Marc Damelin, HP Gerber, Lioudmila Tchistiakova, Frank Loganza, Chris O'Donnell, Puja Sapra. Generation and preclinical characterization of CD123-CPI antibody-drug conjugate (ADC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 935.

Genomic innovations, transcriptional plasticity and gene loss underlying the evolution and divergence of two highly polyphagous and invasive Helicoverpa pest species

BACKGROUND

Helicoverpa armigera and Helicoverpa zea are major caterpillar pests of Old and New World agriculture, respectively. Both, particularly H. armigera, are extremely polyphagous, and H. armigera has developed resistance to many insecticides. Here we use comparative genomics, transcriptomics and resequencing to elucidate the genetic basis for their properties as pests.

RESULTS

We find that, prior to their divergence about 1.5 Mya, the H. armigera/H. zea lineage had accumulated up to more than 100 more members of specific detoxification and digestion gene families and more than 100 extra gustatory receptor genes, compared to other lepidopterans with narrower host ranges. The two genomes remain very similar in gene content and order, but H. armigera is more polymorphic overall, and H. zea has lost several detoxification genes, as well as about 50 gustatory receptor genes. It also lacks certain genes and alleles conferring insecticide resistance found in H. armigera. Non-synonymous sites in the expanded gene families above are rapidly diverging, both between paralogues and between orthologues in the two species. Whole genome transcriptomic analyses of H. armigera larvae show widely divergent responses to different host plants, including responses among many of the duplicated detoxification and digestion genes.

CONCLUSIONS

The extreme polyphagy of the two heliothines is associated with extensive amplification and neofunctionalisation of genes involved in host finding and use, coupled with versatile transcriptional responses on different hosts. H. armigera's invasion of the Americas in recent years means that hybridisation could generate populations that are both locally adapted and insecticide resistant.

[Simultaneous triple semicircular canal plugging and cochlear implantation in advanced Meniere's disease]

Objective: To evaluate the feasibility of combining simultaneous triple semicircular canal plugging (TSCP) and cochlear implantation (CI) to treat vertigo and hearing loss in advanced Meniere's disease(MD) patients, so as to provide an alternative surgical procedure for treating this disorder. Methods: Data from seven patients, who were referred to our hospital and diagnosed with unilateral MD strictly meeting the criteria issued by Chinese Academy of Otolaryngology-Head and Neck Surgery Committee (2006), from Jan. 2015 to Jan. 2016, were retrospectively analyzed in this work. Seven patients, in whom the standardized conservative treatment had been given for at least one year and frequent vertigo still occurred, underwent simultaneous TSCP and CI under general anesthesia via mastoid approach. Postoperative follow-up time was more than six months. Vertigo control and auditory function were measured. Pure tone audiometry, speech perception scores, caloric test, head impulse test (HIT), and vestibular evoked myogenic potential (VEMP) were performed for evaluation of audiological and vestibular functions. Results: All patients had bilateral severe sensorineural hearing loss preoperatively. One side hearing loss was due to MD and another side was due to reasons including sudden sensorineural hearing loss, mumps and other unknown reason. The total control rate of vertigo in seven MD patients was 100.0% in the six-month follow-up, with complete control rate of 85.7% (6/7) and substantial control rate of 14.3% (1/7). Improved hearing threshold and speech perception scores were observed in all study participants. Postoperative average aided hearing threshold was 32.5 dBHL, the average monosyllabic word score was 42.6% and speech perception scores of sentences tested in quiet was 52.3%. Tinnitus improved in five cases, and no significant change in two patients. Post-operatively, all patients suffered from temporary vertigo and balance disorders. Vertigo was disappeared in all patients within 3-5 days, while, an average recovery time of balance disorders was 19.7 days. Six months after treatment, loss of semicircular canal function by caloric test was found in the operation side of all patients and no change in cVEMP or oVEMP test was noted. All patients had no facial paralysis, cerebrospinal fluid leakage, and other complications. Conclusions: A combined approach of TSCP and CI which could control vertigo effectively and improve hearing loss and tinnitus represents an effective and safe therapy for some advanced MD patients.

[Analyses of prognostic factors relevant to acute low-tone sensorineural hearing loss]

Objective: To investigate the prognostic factors relevant to acute low-tone sensorineural hearing loss (ALHL). Methods: 196 adult ALHL patients, including 82 males and 114 females with mean age of (43.1±14.3)years old were included. All patients received the same therapy and were evaluated the curative effect. To evaluate the impact factors on the prognosis of hearing, inclusive of age, gender, time delay before the first visit, degree of deafness, vestibular function, electrocochleogram, and the serum levels of thyroxines by SPSS 18.0 software. Results: Of those 196 patients with ALHL, 124(63.3%) were recovery, 5(2.6%) were excellent better, 42(21.4%) were better, and 25 (12.8%) were poor, with a total effective rate of 87.2%. Among 15 (12.1%) who recurred the hearing loss, 2 developed into Meniere's disease during the follow-up. The mean age of patients with poor hearing effect was significantly older than that of other patients (P<0.05). No relativity was found between gender and hearing curative effect. There existed a statistical difference in total effective rate among subjects with different histories (P<0.05). In addition, the recovery rate was significantly different between groups, i. e., the course of disease was less than 14 days, between 14 days and 6 months, and between 6 months and 2 years (P<0.05). There was no statistical significance in total effective rate among different degrees of deafness (P>0.05). However, in term of the recovery rate, the difference was statistical significance (P<0.05). The recovery rate in patients with mild hearing loss was higher than that in middle or heavy hearing loss (both P<0.05). Among patients with mild deafness, the recovery rate in patients whose history was less than 3 months was significantly higher than that more than 3 months (P<0.05). For moderate deafness patients, the recovery rate in patients whose history was less than 7 days was significantly higher than that more than 1 month (P<0.05). There were statistical differences in hearing effect of 130 (66.3%) patients with abnormal vestibular function in comparison to that with normal vestibular function (χ²=15.1, P<0.05). There were 17(8.7%) patients with abnormal electrocochleogram combined with abnormal vestibular function, and the hearing effects were all poor. There were 45 (23.0%) patients with abnormal thyroxine levels in serum, which was significant higher than that in health adults of 5.9%(χ²=7.26, P<0.01). There was no significant difference in hearing prognosis between patients with abnormal and normal thyroxine levels (χ²=2.51, P>0.05). Conclusions: With respect to ALHL, the hearing effect is associated significantly with the history. The severity of hearing loss is negative prognostic factor for hearing recovery. Age, vestibular function, and electrocochleogram might predict hearing recovery. Gender and thyroxine levels couldn't predict the hearing prognosis, although there is a high incidence rate in patients with ALHL.

[Ultrahigh-frequency hearing thresholds in middleaged and elderly healthy adults]

Objective:To investigate the ultrahigh-frequency(UHF) hearing thresholds in middle-aged and elderly healthy subjects .Method: Healthy subjects(age range: 50-69 ) were divided into two groups,i.e.50-59 year-old group and >59-69 year-old group.Each subject was tested with both conventional-frequency(0.25,0.50,1.00,2.00,4.00,6.00 and 8.00 kHz) and ultrahigh-frequency(9.0,10.0,11.5,12.5,14.0,16.0,18.0,and 20.0 kHz) audiometry.UHF was performed twice to evaluate the reliability.The best hearings among 20-29 aged healthy adults were considered as normal controls.Results:Seventy five middle-aged and elderly subjects were included,with 39 subjects(78 ears) being 50-59 years old and 36(72 ears) being >59-69 year-old.Eighteen subjects(36 ears) aging from 20 to 29 were considers as controls.For the conventional-frequency,the hearing thresholds in middle-aged and elderly people were significantly higher than those in young people(all P<0.05),especially at ≥4 kHz.Although the conventional-frequency thresholds in >59-69 year-old group were higher than those in 50-59 year-old,the difference was significant just at 4 kHz(P<0.05).The UHF thresholds in middle-aged and elderly people were significantly higher than those in young people(all P<0.05).The thresholds at 9,10,11.5 and 12.5 kHz in >59-69 year-old people were significantly increased than those in 50-59 year-old counterparts(all P<0.05).Hearing threshold at ≥12.5 kHz couldn't be detected in some subjects in middle-aged and elderly group.The response rate at UHF in >59-69 year-old people were just higher than that in 50-59 year-old counterparts (P>0.05),and none responded at 18 and 20 kHz.The standard deviations(SDs) for <14 kHz in 50-59 year-old and for <11.5 kHz in >59-69 year-old subjects,were both higher than that in 20-29 year old counterparts.Above 6 kHz,the SDs in 50-59 year-old subjects were significantly higher than those in >59-69 year-old subjects(all P<0.05).Conclusion:For middle-aged and elderly people,the hearing loss may occur from 4 kHz.Hearing thresholds at UHF were increased with age,and it might be used as an early indicator for age-induced hearing loss.However,the UHF sensitivity decreased as the frequency increased beyond 14 kHz.

Distribution and Characteristics of Colletotrichum spp. Associated with Anthracnose of Strawberry in Hubei, China

Anthracnose caused by Colletotrichum spp. is a serious disease of strawberry. The etiology of anthracnose of strawberry is complex, and several Colletotrichum spp. have been regarded as causal agents. In the present study, multilocus (actin, β-tubulin, calmodulin, glyceraldehyde-3-phosphate dehydrogenase, and chitin synthase) phylogenetic analysis revealed that 100 isolates of Colletotrichum associated with anthracnose of strawberry in central China belong to five species. In total, 97 isolates were identified belonging to the Colletotrichum gloeosporioides species complex, with C. murrayae, C. gloeosporioides, C. fructicola, and C. aenigma accounting for 81, 8, 4, and 4% of the total isolates, respectively. Three isolates belonging to the C. acutatum complex were identified as C. nymphaeae. On inoculated strawberry plants, isolates of C. fructicola and C. murrayae species showed strong pathogenicity to both leaves and petioles of strawberry, with plant mortality 30 days after inoculation of 77.8 and 55.6%, respectively. C. gloeosporioides, C. aenigma, and C. nymphaeae showed strong pathogenicity to leaves but weak pathogenicity to petioles, with plant mortality 30 days after inoculation of 5.6, 16.7, and 11.1%, respectively. The five species were divided into four classes based on their maximum growth temperatures. Isolates of C. murrayae and C. gloeosporioides were more tolerant to high temperature (>34°C) than isolates of other species, followed by C. fructicola and C. aenigma. Isolates of C. nymphaeae, which are only distributed in areas of higher altitude (1,100 m), were highly sensitive to higher temperature. These results indicate that pathogenicity and adaptation to temperature are important factors in the distribution of Colletotrichum spp. on strawberry plants. This research may increase our understanding of how Colletotrichum spp. emerge and spread to geographical regions with different latitudes or elevations.

An allelic series of miR-17 ∼ 92-mutant mice uncovers functional specialization and cooperation among members of a microRNA polycistron

Polycistronic microRNA clusters are a common feature of vertebrate genomes. The coordinated expression of miRNAs belonging to different seed families from a single transcription unit suggests functional cooperation, but this hypothesis has not been experimentally tested. Here we report the characterization of an allelic series of genetically engineered mice harboring selective targeted deletions of individual components of miR-17~92. Our results demonstrate the co-existence of functional cooperation and specialization among members of this cluster, identify a novel function for the miR-17 seed family in controlling axial patterning in vertebrates, and show that loss of miR-19 selectively impairs Myc-driven tumorigenesis in two models of human cancer. By integrating phenotypic analysis and gene expression profiling, we provide a genome-wide view of how components of a polycistronic miRNA-cluster affect gene expression in vivo. The reagents and datasets reported here will accelerate exploration of the complex biological functions of this important miRNA cluster.

In vivo engineering of oncogenic chromosomal rearrangements with the CRISPR/Cas9 system

Chromosomal rearrangements play a central role in the pathogenesis of human cancers and often result in the expression of therapeutically actionable gene fusions¹. A recently discovered example is a fusion between the Echinoderm Microtubule-associated Protein-like 4 (EML4) and the Anaplastic Lymphoma Kinase (ALK) genes, generated by an inversion on the short arm of chromosome 2: inv(2)(p21p23). The EML4-ALK oncogene is detected in a subset of human non-small cell lung cancers (NSCLC)² and is clinically relevant because it confers sensitivity to ALK inhibitors³. Despite their importance, modeling such genetic events in mice has proven challenging and requires complex manipulation of the germline. Here we describe an efficient method to induce specific chromosomal rearrangements in vivo using viral-mediated delivery of the CRISPR/Cas9 system to somatic cells of adult animals. We apply it to generate a mouse model of Eml4-Alk-driven lung cancer. The resulting tumors invariably harbor the Eml4-Alkinversion, express the Eml4-Alk fusion gene, display histo-pathologic and molecular features typical of ALK+ human NSCLCs, and respond to treatment with ALK-inhibitors. The general strategy described here substantially expands our ability to model human cancers in mice and potentially in other organisms.

Intact p53-dependent responses in miR-34-deficient mice

MicroRNAs belonging to the miR-34 family have been proposed as critical modulators of the p53 pathway and potential tumor suppressors in human cancers. To formally test these hypotheses, we have generated mice carrying targeted deletion of all three members of this microRNA family. We show that complete inactivation of miR-34 function is compatible with normal development in mice. Surprisingly, p53 function appears to be intact in miR-34–deficient cells and tissues. Although loss of miR-34 expression leads to a slight increase in cellular proliferation in vitro, it does not impair p53-induced cell cycle arrest or apoptosis. Furthermore, in contrast to p53-deficient mice, miR-34–deficient animals do not display increased susceptibility to spontaneous, irradiation-induced, or c-Myc–initiated tumorigenesis. We also show that expression of members of the miR-34 family is particularly high in the testes, lungs, and brains of mice and that it is largely p53-independent in these tissues. These findings indicate that miR-34 plays a redundant function in the p53 pathway and suggest additional p53-independent functions for this family of miRNAs.

MicroRNAs (miRNAs) are small, non-coding RNAs that broadly regulate gene expression. MicroRNA deregulation is a common feature of human cancers, and numerous miRNAs have oncogenic or tumor suppressive properties. Members of the miR-34 family (miR-34a, miR-34b, and miR-34c) have been widely speculated to be important tumor suppressors and mediators of p53 function. Despite the growing body of evidence supporting this hypothesis, previous studies on miR-34 have been done in vitro or using non-physiologic expression levels of miR-34. Here, we probe the tumor suppressive functions of the miR-34 family in vivo by generating mice carrying targeted deletion of the entire miR-34 family. Our results show that the miR-34 family is not required for tumor suppression in vivo, and they suggest p53-independent functions for this family of miRNAs. Importantly, the mice generated from this study provide a tool for the scientific community to further investigate the physiologic functions of the miR-34 family.

microRNA-29a induces aberrant self-renewal capacity in hematopoietic progenitors, biased myeloid development, and acute myeloid leukemia

The function of microRNAs (miRNAs) in hematopoietic stem cells (HSCs), committed progenitors, and leukemia stem cells (LSCs) is poorly understood. We show that miR-29a is highly expressed in HSC and down-regulated in hematopoietic progenitors. Ectopic expression of miR-29a in mouse HSC/progenitors results in acquisition of self-renewal capacity by myeloid progenitors, biased myeloid differentiation, and the development of a myeloproliferative disorder that progresses to acute myeloid leukemia (AML). miR-29a promotes progenitor proliferation by expediting G1 to S/G2 cell cycle transitions. miR-29a is overexpressed in human AML and, like human LSC, miR-29a-expressing myeloid progenitors serially transplant AML. Our data indicate that miR-29a regulates early hematopoiesis and suggest that miR-29a initiates AML by converting myeloid progenitors into self-renewing LSC.

Genetic dissection of the miR-17~92 cluster of microRNAs in Myc-induced B-cell lymphomas

The miR-17 approximately 92 cluster is frequently amplified or overexpressed in human cancers and has emerged as the prototypical oncogenic polycistron microRNA (miRNA). miR-17 approximately 92 is a direct transcriptional target of c-Myc, and experiments in a mouse model of B-cell lymphomas have shown cooperation between these two oncogenes. However, both the molecular mechanism underlying this cooperation and the individual miRNAs that are responsible for it are unknown. By using a conditional knockout allele of miR-17 approximately 92, we show here that sustained expression of endogenous miR-17 approximately 92 is required to suppress apoptosis in Myc-driven B-cell lymphomas. Furthermore, we show that among the six miRNAs that are encoded by miR-17 approximately 92, miR-19a and miR-19b are absolutely required and largely sufficient to recapitulate the oncogenic properties of the entire cluster. Finally, by combining computational target prediction, gene expression profiling, and an in vitro screening strategy, we identify a subset of miR-19 targets that mediate its prosurvival activity.

CXCR4 is required for the quiescence of primitive hematopoietic cells

The quiescence of hematopoietic stem cells (HSCs) is critical for preserving a lifelong steady pool of HSCs to sustain the highly regenerative hematopoietic system. It is thought that specialized niches in which HSCs reside control the balance between HSC quiescence and self-renewal, yet little is known about the extrinsic signals provided by the niche and how these niche signals regulate such a balance. We report that CXCL12 produced by bone marrow (BM) stromal cells is not only the major chemoattractant for HSCs but also a regulatory factor that controls the quiescence of primitive hematopoietic cells. Addition of CXCL12 into the culture inhibits entry of primitive hematopoietic cells into the cell cycle, and inactivation of its receptor CXCR4 in HSCs causes excessive HSC proliferation. Notably, the hyperproliferative Cxcr4(-/-) HSCs are able to maintain a stable stem cell compartment and sustain hematopoiesis. Thus, we propose that CXCR4/CXCL12 signaling is essential to confine HSCs in the proper niche and controls their proliferation.

Control of the B cell-intrinsic tolerance programs by ubiquitin ligases Cbl and Cbl-b

B cell receptor (BCR) signaling plays a critical role in B cell tolerance and activation. Here, we show that mice with B cell-specific ablation of both Cbl and Cbl-b (Cbl-/-Cblb-/-) manifested systemic lupus erythematosus (SLE)-like autoimmune disease. The Cbl double deficiency resulted in a substantial increase in marginal zone (MZ) and B1 B cells. The mutant B cells were not hyperresponsive in terms of proliferation and antibody production upon BCR stimulation; however, B cell anergy to protein antigen appeared to be impaired. Concomitantly, BCR-proximal signaling, including tyrosine phosphorylation of Syk tyrosine kinase, Phospholipase C-gamma2 (PLC-gamma2), and Rho-family GTP-GDP exchange factor Vav, and Ca2+ mobilization were enhanced, whereas tyrosine phosphorylation of adaptor protein BLNK was substantially attenuated in the mutant B cells. These results suggested that the loss of coordination between these pathways was responsible for the impaired B cell tolerance induction. Thus, Cbl proteins control B cell-intrinsic checkpoint of immune tolerance, possibly through coordinating multiple BCR-proximal signaling pathways during anergy induction.

Trans-dominant cellular inhibition of DC-SIGN-mediated HIV-1 transmission

Background

Dendritic cell (DC) transmission of human immunodeficiency virus (HIV) to CD4+ T cells occurs across a point of cell-cell contact referred to as the infectious synapse. The relationship between the infectious synapse and the classically defined immunological synapse is not currently understood. We have recently demonstrated that human B cells expressing exogenous DC-SIGN, DC-specific intercellular adhesion molecule-3 (ICAM-3)-grabbing nonintegrin, efficiently transmit captured HIV type 1 (HIV-1) to CD4+ T cells. K562, another human cell line of hematopoietic origin that has been extensively used in functional analyses of DC-SIGN and related molecules, lacks the principal molecules involved in the formation of immunological synaptic junctions, namely major histocompatibility complex (MHC) class II molecules and leukocyte function-associated antigen-1 (LFA-1). We thus examined whether K562 erythroleukemic cells could recapitulate efficient DC-SIGN-mediated HIV-1 transmission (DMHT).

Results

Here we demonstrate that DMHT requires cell-cell contact. Despite similar expression of functional DC-SIGN, K562/DC-SIGN cells were inefficient in the transmission of HIV-1 to CD4+ T cells when compared with Raji/DC-SIGN cells. Expression of MHC class II molecules or LFA-1 on K562/DC-SIGN cells was insufficient to rescue HIV-1 transmission efficiency. Strikingly, we observed that co-culture of K562 cells with Raji/DC-SIGN cells impaired DMHT to CD4+ T cells. The K562 cell inhibition of transmission was not directly exerted on the CD4+ T cell targets and required contact between K562 and Raji/DC-SIGN cells.

Conclusions

DMHT is cell type dependent and requires cell-cell contact. We also find that the cellular milieu can negatively regulate DC-SIGN transmission of HIV-1 in trans.

Bronchial stenosis due to anthracofibrosis

STUDY OBJECTIVES

To define the clinical characteristics of the patients showing bronchoscopic findings of bronchial narrowing or obliteration with black pigmentation on overlying mucosa (we named this finding as "anthracofibrosis"), and to determine the association of anthracofibrosis with tuberculosis.

PATIENTS AND METHODS

The subjects of this study consisted of 28 patients; 8 men and 20 women, ranging in age from 42 to 86 years. The distinctive clinical features, natures of bronchoscopic lesions, and radiologic findings were analyzed retrospectively and summarized. Bacteriologic studies and results of pathologic examinations were also assessed.

RESULTS

Chief complaints were cough (20/28) and dyspnea on exertion (17/28). The abnormal bronchoscopic findings were identified most frequently in the right middle lobe bronchus (n=21/28) while more than one part of the bronchial tree was narrowed in 22 patients. Abnormalities of bronchial airways on CT were associated with peribronchial cuffs of soft tissue or surrounding lymph nodes. In 17 patients, active tuberculous infection was confirmed either bacteriologically (n=15) and/or histologically (n=8). Pathologic study of the lesion obtained by bronchoscopic biopsy or thoracotomy showed dense bronchial and/or peribronchial fibrosis with interspersed black pigments.

CONCLUSIONS

These findings strongly suggest that bronchial stenosis or obliteration with anthracotic pigmentation in the mucosa was caused by a fibrotic response to active or old tuberculous infection. To prevent the spread of tuberculosis and avoid unnecessary invasive procedures, detailed examinations for the presence of active tuberculosis should be performed in patients with this unique bronchoscopic finding.

The seventh nationwide tuberculosis prevalence survey in Korea, 1995

SETTING

Nationwide random sample survey for tuberculosis prevalence in Korea in 1995.

OBJECTIVE

To investigate the prevalence of tuberculosis infection, morbidity and drug resistance, and BCG coverage, and to compare the findings with those of the previous six surveys.

DESIGN

The following investigations were performed: tuberculin test, BCG scar screening, chest miniature radiography (70 x 70 mm) for those aged over five years, sputum direct smear, culture and drug susceptibility test, and a questionnaire to obtain history of antituberculosis chemotherapy and symptoms.

RESULTS

The coverages of the 1995 survey were as follows: tuberculin 87.0%, radiology 88.4%, bacteriology 98.3%. The observed tuberculin positivity (> or =10 mm in diameter) of subjects aged under 30 was 15.5%. The prevalence of pulmonary tuberculosis per 100000 has decreased in the last 30 years: direct smear positive from 686 to 93, smear and/or culture positive from 940 to 219, active tuberculosis from 5065 to 1032. Rates of drug resistance have also fallen: of those with no previous chemotherapy from 26.2% to 5.8%, of those with history of chemotherapy from 55.2% to 25.0%, and in total from 38.0% to 9.9%. BCG scar prevalence of infants (aged under one year) was 87.7%, and of those under 30 it was 91.8% in 1995.

CONCLUSION

Tuberculosis prevalences and the drug resistance rates have decreased significantly.

Tuberculosis of the trachea and main bronchi: CT findings in 17 patients

OBJECTIVE

The purpose of our study was to describe the CT findings of tuberculosis of the trachea and main bronchi.

MATERIALS AND METHODS

Initial (n = 17) and follow-up (n = 7) CT scans were available from 17 patients (five men and 12 women; aged 25-82 years old) with tracheobronchial tuberculosis. The diagnosis of tuberculosis was based on bronchoscopic, microbiologic, or pathologic findings.

RESULTS

The trachea (n = 6), the right main bronchus (n = 6), and the left main bronchus (n = 4) were involved in 10 patients with actively caseating tuberculosis. These airways showed irregular (n = 11) or smooth (n = 4) circumferential narrowing and occlusion (n = 1). Also, the trachea (n = 2), the right main bronchus (n = 1), and the left main bronchus (n = 6) were involved in seven patients with fibrotic tuberculosis. These airways showed smooth (n = 4) or irregular (n = 3) circumferential narrowing and occlusion (n = 2). Mediastinitis (increased densities in mediastinal fat) was seen in four of 10 patients with active tuberculosis but not in any of the seven patients with fibrotic disease. Tracheal tuberculosis, which has always been associated with bronchial disease, involved the distal trachea and exceeded 3 cm in length. After the seven patients underwent initial scans and antituberculous chemotherapy, serial CT scans showed improvement in seven of 11 lesion sites: normalized airways (n = 4) or smoothing from irregular narrowing (n = 3). The remaining four sites showed no change.

CONCLUSION

On CT scans, actively caseating tracheobronchial tuberculosis showed circumferential and predominantly irregular luminal narrowing and mediastinitis. When fibrotic disease was found, a CT scan revealed equal distribution of smooth and irregular narrowing and less wall thickening than was seen in patients with active disease. On CT scans, tracheal tuberculosis involved the long segment of the distal trachea, a condition associated with bronchial tuberculosis.

Diagnosis and treatment of bacterial pneumonia in Korea

Even with advancements in knowledge the problem of pneumonia will not be eliminated. It should be understood who is at risk, why such people develop pneumonia, what causes the pneumonia, and respiratory infection should be managed and prevented. The relative frequency of the isolation of various etiologic agents that cause bacterial pneumonia differ according to age group, geography, socio-economic status, underlying disease, time of year, and possible concomitant viral illnesses. Prompt identification of the causative agent is vital in the management of pneumonia. The present status of elucidating the etiologic agent is far from complete and recently, newer techniques using DNA probes and polymerase chain reactions were used for the identification of microbial pathogens. The timely use of appropriate systemic antibacterial therapy eradicates the pathogens. Considering the alterations of the etiologic agents of bacterial pneumonia and antibiotic susceptibilities, attention should be directed to the usage of antimicrobial agents in order to maximize the efficacy and the therapeutic implications.

Mechanisms of ethanol-induced suppression of a primary antibody response in a mouse model for binge drinking

A previous study in this laboratory demonstrated that a single dose of EtOH causes thymic atrophy and that elevated levels of endogenous glucocorticoids are responsible, at least in part, for this effect. In the present study using the same animal model, the effect of EtOH on the T-dependent antibody response to sheep red blood cells (SRBC) was evaluated. In addition, the effects of EtOH on the SRBC-induced expression of selected cytokines known to enhance or regulate humoral responses were evaluated. Administration of EtOH at 5.0 to 7.0 g/kg to B6C3F1 mice significantly and dose-responsively inhibited the generation of antibody-forming cells (AFC) after immunization in vivo or in vitro in Mishell-Dutton cultures. In contrast, direct addition of EtOH or its major metabolites to Mishell-Dutton cultures did not decrease the AFC response. In vivo administration of EtOH caused substantial decreases in the SRBC-induced expression of interleukin (IL)-1-beta, IL-2 and IL-4 mRNA in the spleen, as indicated by reverse transcription-polymerase chain reaction. The suppressed AFC responses and suppressed cytokine gene expression were prevented by RU 486, a potent glucocorticoid antagonist. Thus, suppression of cytokine gene expression by elevated levels of endogenous glucocorticoids may play a role in EtOH-induced suppression of the primary humoral response to SRBC. However, differences in dose-response patterns for suppression of cytokine gene expression and suppression of the AFC response suggest the involvement of additional factors.

Thymic atrophy caused by ethanol in a mouse model for binge drinking: involvement of endogenous glucocorticoids

Consumption of large amounts of ethanol (EtOH) in a single drinking episode is common, but very little is known about the immunological effects of such occurrences. Exposure to EtOH for several days is immunosuppressive in rodent models, and a single dose of EtOH causes substantial increases in endogenous glucocorticoid levels which might have immunosuppressive effects. In the present study, the effects of a single dose of EtOH on the thymus and the role of endogenous glucocorticoids in these effects were examined in B6C3F1 female mice. A single dose of EtOH decreased thymus weight and cellularity, predominantly by elimination of CD4+CD8+ (immature) thymocytes. This occurred over a broad range of EtOH doses and was associated with behavioral effects (ranging from mild ataxia to unresponsiveness) similar to those noted in human binge drinkers. Several lines of evidence indicate that the effects of EtOH on the thymus are mediated by endogenous glucocorticoids: (1) corticosterone levels in EtOH-treated mice increased more than 10-fold and remained significantly elevated for up to 12 hr; (2) the most glucocorticoid-sensitive thymocytes (CD4+CD8+ cells) were preferentially depleted by EtOH; (3) before thymocyte depletion was evident, substantial DNA fragmentation occurred in the thymus as would be expected in the case of glucocorticoid-induced apoptosis; (4) the glucocorticoid antagonist, RU 486, blocked thymic atrophy and DNA fragmentation in EtOH-treated mice; (5) EtOH and its major metabolites at concentrations comparable to or greater than expected in vivo did not decrease thymocyte viability in 20-hr cultures, indicating that direct action of EtOH or its metabolites on thymocytes does not play an important role in EtOH-induced thymic atrophy. These results suggest that a single dose of EtOH induces thymic atrophy which is predominantly mediated by increased levels of endogenous glucocorticoids. The mouse model described here should be useful in evaluating other effects of binge drinking on the immune system, and the experimental strategy described should be applicable in investigating the role of endogenous glucocorticoids in thymic atrophy induced by other chemicals and drugs.

The sixth Nationwide Tuberculosis Prevalence Survey in Korea, 1990

SETTING

Nationwide random sample survey for tuberculosis in 1990.

OBJECTIVE

To investigate the prevalence of tuberculosis infection, morbidity and drug resistance and BCG coverage, and to compare the findings with those of the previous 5 surveys.

DESIGN

The following investigations were performed: tuberculin test, BCG scar screening, chest miniature radiography (70 mm x 70 mm) for those aged over 5 years, sputum direct smear, culture and drug susceptibility test, and a questionnaire to obtain history of chemotherapy and symptoms.

RESULTS

The coverage of the investigation has been of more than 95% in each survey. The main findings are as follows: BCG coverage of those aged under 30 and of infants (aged under 1 year) has increased from 24% to 86% and from 1% to 79% respectively. The observed tuberculin positivity (> or = 10 mm in diameter) of subjects aged under 30 has decreased from 45% to 27%. The reduction of positivity was significant in children aged 5-9 years, from 34% to 8%. The annual risk of infection has dropped by over 6% annually. The prevalence of pulmonary tuberculosis per 100,000 has decreased: direct smear-positive from 690-143, smear and/or culture positive from 940-241 and active cases from 5065-1842 respectively. The drug resistance rate had increased to the peak of 47% in 1980, but had decreased to 27% in the last survey.

CONCLUSION

The tuberculosis situation has improved significantly in every aspect in the last 25 years.

[Study of anti-lipid peroxidation of vitamin E in human body]

Anti-lipid peroxidization in vivo has been observed by VE per os. The results have proved that contents of serum VE and RBC VE obviously were increased and that contents of serum LPO and RBC LPO obviously were decreased in normal adults and patients with acute hepatitis taking VE (200 mg/d) after 10 days. Specially, there was significant change in the patients with acute hepatitis group (53 cases). Increased levels of VE in serum and RBC were 137% and 97% respectively. Decreased levels of LPO in serum and RBC were 48% and 20% respectively. The study showed that VE has very strong anti-lipid peroxidization.

Morphine suppresses primary humoral immune responses by a predominantly indirect mechanism

Morphine suppresses humoral immune responses, causes thymic hypoplasia and suppresses NK (natural killer) activity in animal models. There is evidence that thymic hypoplasia and NK suppression are predominantly mediated by indirect mechanisms. The mechanism of morphine-induced humoral immunosuppression is less certain. Recent reports suggest that morphine and other opioids can directly act on cells of the immune system to suppress the generation of antibody-forming cells (AFC) in Mishell-Dutton cultures. The present study was designed to assess the roles of direct and indirect mechanisms in morphine-induced suppression of humoral immunity. Splenocytes from mice treated with morphine by s.c. implantation of a slow-release 75 mg pellet were dysfunctional in Mishell-Dutton cultures. Exposure to morphine in vivo for 12 or 24 hr caused significant suppression of the AFC production stimulated by sheep erythrocytes in Mishell-Dutton cultures. In contrast, direct addition of morphine or the kappa selective opioid agonist U50,488H to Mishell-Dutton cultures under a variety of conditions had little or no effect on AFC generation. These results indicate that suppression of humoral responses by morphine is not primarily mediated by direct action of morphine on the immune system. Suppression of AFC responses by administration of morphine in vivo was substantially blocked by treating mice with the glucocorticoid antagonist RU 38486, suggesting that glucocorticoids may be involved in the indirect mechanism by which morphine causes splenocyte dysfunction.

Small airway disease in rheumatoid arthritis

Variety of pulmonary lesions are thought to be associated with rheumatoid arthritis (RA). These lesions traditionally have included pleurisy with or without effusion, Caplan's syndrome, pulmonary rheumatoid nodules, diffuse interstitial fibrosis, and pulmonary arteritis and hypertension. But little attention has been paid to the airways in RA. Recently, several reports have suggested an association between airflow limitation and RA, but its incidence is not known. Also whether there exists a parameter of disease activity of RA, suggesting the presence of small airway disease (SAD) is not clear. To answer these questions, the serologic parameters which reflect the disease activity of RA and pulmonary function tests which reflect small airway dysfunction were performed on 36 lifetime nonsmokers with RA who had normal chest x-ray findings. The prevalence of SAD and the relationships between the disease activity parameters of RA and pulmonary function were observed. The results were as follows. The percentages of patients with abnormal values for diffusing capacity, frequency dependence of compliance (C1.0/C0.0), forced expiratory flow 25-75%, Vmax50% and Vmax 75% were 45.5%, 62.5%, 40%, 22.8% and 11.4%, respectively. There was statistically significant negative correlation between C1.0/C0.0 and ESR. But consistent correlation between other pulmonary function tests and clinical and serologic parameters of RA, and differences in pulmonary function between patients who were serologically positive and negative for CRP and FANA, were not found. In conclusion, SAD, without the influence of smoking, is frequently associated with RA, but the presence of SAD cannot be predicted from any clinical and serologic parameters of RA currently in use.

The first report of diffuse panbronchiolitis in Korea: five case reports

Diffuse panbronchiolitis (DPB), which is prevalent in Japan, is known to be rare outside Japan. Although a case of diffuse panbronchiolitis in a second generation Korean was reported in Japan in 1986, no case has been reported in Korea. Recently we found 5 cases of diffuse panbronchiolitis in Korea, two histologically proven and three clinically and radiologically suspected. All 5 cases had the typical respiratory symptoms and signs and a history of chronic sinusitis. In three clinically and radiologically suspected cases, high resolution computed tomography showed the typical findings of DPB and other diseases such as pulmonary emphysema, bronchial asthma, chronic bronchitis and bronchiectasis could be ruled out. More cases of DPB are expected to be found in Korea in the near future.

Immunotoxicological characteristics of sodium methyldithiocarbamate

This study was conducted to assess immunotoxicological effects and selected general toxicological effects of sodium methyldithiocarbamate (SMD). Initially, the compound was administered orally to female B6C3F1 mice at 300 mg/kg/day for 3, 5, 10, or 14 days. Body, liver, kidney, spleen, and thymus weights were measured. Selected hematological and bone marrow parameters were examined. Flow cytometric analysis was used to assess changes in lymphocyte subpopulations in the thymus and spleen, and production of antibody-forming cells in vitro was measured. Major effects included decreased thymus weight at all time points; increased spleen weight after 10 or 14 days of exposure, increased bone marrow cellularity after 10 or 14 days of exposure, significant decreases in mature lymphocyte subpopulations which were greater in the thymus than in the spleen, relatively selective depletion of the major subpopulation of thymocytes (CD4+CD8+), and decreased body weight. Overall patterns of changes were consistent with the conclusion that SMD rapidly depletes most CD4+CD8+ thymocytes, more slowly depletes a smaller number of mature lymphocytes in the thymus and spleen, and induces compensatory and/or detoxication mechanisms after 10-14 days of exposure. Subsequent experiments were done to assess selected immune function parameters. SMD at 50-300 mg/kg/day for 7 days caused substantial, dose-dependent suppression of NK cell activity. No suppression of antibody production in vivo or splenocyte responses to mitogens or allogeneic lymphocytes in vitro was detected. NK cell activity, thymus weight, and CD4+CD8+ thymocyte numbers were suppressed by dermal administration of SMD.(ABSTRACT TRUNCATED AT 250 WORDS)

[Effect of praziquantel treatment on pulmonary lesions of rats infected with Paragonimus iloktsuenensis]

An experimental pathological study was performed to observe the effect of praziquantel treatment on the pulmonary lesions of the rat lung fluke, Paragonimus iloktsuenensis. The metacercariae were obtained from the freshwater crab, Sesarma dehaani, and 40 rats (wistar) were fed each with 10 metacercariae. On 20 rats praziquantel treatment (100mg/kg/day x 5 days) was done at 5 weeks after the infection while remaining 20 rats were kept untreated for use as controls. The drug-treated rats and the untreated ones were sacrificed 3, 7, 14, 21 or 28 days later for the observation of lung pathology. The rats infected with P. iloktsuenensis showed remarkable pulmonary changes; gross features of hemorrhagic and nodular worm capsules protruded on to the surface of the lung, and histologically local atelectasis, inflammatory cell infiltration, and egg granuloma around the worm capsules each containing one or two worms. Praziquantel treatment of the rats was shown to be highly effective in killing the worms and to lead them to degenerate, as early as in 3 days post-treatment. Almost all worms in the lung were dead and absorbed by the host cells in 21 days post-treatment, except a few living ones seen in a rat of 14-day post-treatment group. In most of the rats treated the pulmonary lesions showed the signs of resolution; regression of worm capsules with mummification of worms, decrease of inflammatory cell infiltration, improvement in the degree of atelectasis, and decreases in the frequency and size of the egg granuloma. From the results it is concluded that praziquantel is highly effective for the treatment of rat P. iloktsuenensis infection in the lung, not only by its direct killing effect of the worms but also due to the excellent resolution capacity of the pulmonary tissues.

Leptospirosis of the lung: radiographic findings in 58 patients

Leptospirosis is the disease produced by any of the group of spirochetes of the genus Leptospira. The main organs involved are the liver, central nervous system, kidneys, skeletal muscle, and lungs. Thirty-seven (64%) of 58 patients with leptospirosis, proved by positive serology, had pulmonary radiographic findings. Three radiographic patterns were evident: (1) 21 (57%) of the 37 patients had small nodular densities, (2) six (16%) had large confluent areas of consolidation, and (3) 10 (27%) had diffuse, ill-defined, ground-glass density. Serial radiographs showed a tendency for the nodular pattern to be followed by confluent consolidation and/or ground-glass density. Abnormalities were bilateral, nonlobar in all cases, and had a marked tendency toward peripheral predominance. Pulmonary abnormalities resolved within 15 days, except in eight patients who died because of respiratory failure (six patients) or other causes (two patients). In order to correlate pathology with the radiographic findings, Leptospira, isolated from a patient, was injected intraperitoneally into 20 guinea pigs. All lungs from the guinea pigs showed petecheal hemorrhage, which progressed to large confluent areas of hemorrhage. The typical pulmonary radiographic findings of leptospirosis are compatible with the multifocal pulmonary hemorrhage seen in the guinea pigs.

Antibody changes in paragonimiasis patients after praziquantel treatment as observed by ELISA and immunoblot

To observe antibody changes after praziquantel treatment in paragonimiasis, a total of 46 serum samples from 13 serologically diagnosed patients was collected for 4-28 months. The specific antibody (IgG) levels were measured by enzyme-linked immunosorbent assay (ELISA). All but one patient who needed retreatment became symptom-free within a week. Antibody levels were dropped near to or below a cut-off absorbance (abs.) of 0.25 in varying intervals from 4 to 18 months. Of 9 patients who were retested within 3 months, 5 revealed temporary elevation of antibody level. After the elevation, the levels began to decline slowly to negative ranges. If treated earlier after symptoms developed, the temporary elevation did not occur and intervals to negative conversion were shorter. By sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE)/immunoblot, antigen-antibody reactions in individual patient faded gradually without significant changes in reacting antigen bands.

Transbronchial catheter drainage via fiberoptic bronchoscope in intractable lung abscess

The use of the fiberoptic bronchoscope as a drainage procedure for lung abscess has become more and more widespread. We have recently adopted the technique of inserting a simple polyethylene catheter through the flexible fiberoptic bronchoscope into the abscess cavity of 11 patients with lung abscess. All cases had not responded to aggressive postural drainage and adequate antibiotic therapy for at least a week. The results were as follows: 1) Among 11 patients, the therapeutic response was dramatic in 6 patients. 2) In the successful group, the abscess sizes were greater than 8cm in diameter and the airfluid levels were higher than two-thirds of the cavity. 3) Additional diagnoses, other than bacterial lung abscess, could be made in 2 cases when otherwise the diagnosis would have remained in doubt. The authors suggest that catheter drainage via fiberoptic bronchoscope is an effective treatment modality in the large lung abscess with a high air-fluid level which is intractable to other medical approaches, and it is also a safe procedure.

Alveolar hemorrhage associated with crescentic glomerulonephritis--a case report

Alveolar hemorrhage is a life threatening condition which requires an urgent diagnosis and treatment. We report a case of alveolar hemorrhage associated with crescentic glomerulonephritis without immune complex deposition with a review of the literature.