EGFR gene amplification in breast cancer: correlation with epidermal growth factor receptor mRNA and protein expression and HER-2 status and absence of EGFR-activating mutations.

The human epidermal growth factor receptor (HER) family of receptor tyrosine kinase has been extensively studied in breast cancer; however, systematic studies of EGFR gene amplification and protein overexpression in breast carcinoma are lacking. We studied EGFR gene amplification by chromogenic in situ hybridization (CISH) and protein expression by immunohistochemistry in 175 breast carcinomas, using tissue microarrays. Tumors with >5 EGFR gene copies per nucleus were interpreted as positive for gene amplification. Protein overexpression was scored according to standardized criteria originally developed for HER-2. EGFR mRNA levels, as measured by Affymetrix U133 Gene Chip microarray hybridization, were available in 63 of these tumors. HER-2 gene amplification by fluorescence in situ hybridization (FISH) and protein overexpression by immunohistochemistry were also studied. EGFR gene amplification (copy number range: 7-18; median: 12) was detected in 11/175 (6%) tumors, and protein overexpression was found in 13/175 (7%) tumors. Of the 11 tumors, 10 (91%) with gene amplification also showed EGFR protein overexpression (2+ or 3+ by immunohistochemistry). The EGFR mRNA level, based on Affymetrix U133 chip hybridization data, was increased relative to other breast cancer samples in three of the five tumors showing gene amplification. Exons 19 and 21 of EGFR, the sites of hotspot mutations in lung adenocarcinomas, were screened in the 11 EGFR-amplified tumors but no mutations were found. Three of these 11 tumors also showed HER-2 overexpression and gene amplification. Approximately 6% of breast carcinomas show EGFR amplification with EGFR protein overexpression and may be candidates for trials of EGFR-targeted antibodies or small inhibitory molecules.     

Interferon-gamma is an autocrine mediator for dendritic cell maturation

Maturation of dendritic cells (DC) is critical for efficient antigen presentation and initiation of an immune response. Interferon-gamma (IFN-gamma) is an important Th1 cytokine. In this study, we investigated the role of IFN-gamma in DC maturation using either IFN-gamma receptor deficient- or IFN-gamma overexpression-models. We showed that immature DC generated in vitro from bone marrow (BM) progenitor cells produced low level of IFN-gamma. After LPS stimulation, DC produced more IFN-gamma, and IFN-gamma productions were at comparable levels among C57BL/6 mice-derived DC (C57BL/6 DC), wild-type 129 mice-derived DC (129 DC) and IFN-gamma receptor deficient 129 mice-derived DC (IFN-gammaR-/-DC). We found that IFN-gammaR-/-DC exhibited decreased expression of CD54, CD86, reduced capacity to secrete IL-1beta and IL-12p70, and impaired capacity to stimulate alloreactive T cells and to drive Th1 differentiation. Transfection of IFN-gamma gene into DC promoted DC to express higher CD40, CD54, CD80, CD86, CCR7 and I-Ab, secrete more IL-1beta and IL-12p70, and more potently activate both CD4 and CD8 T cells. These data suggest that IFN-gamma signaling pathway is important for the maturation of DC in an autocrine fashion.     

Association of genetic polymorphism in plasminogen activator inhibitor-1 gene with endometrial hypoplasia in infertile women

OBJECTIVE: To investigate the relationship between the plasminogen activator inhibitor (PAI-1) polymorphisms and endometrial hypoplasia in infertile women. METHODS: The study was conducted in 105 primary infertile patients with endometrial hypoplasia diagnosed by pathology and the thickness of endometrium by B-mode ultrasound and 85 controls who were not pregnant and had normal fertility. The -675 4G/5G polymorphism in the PAI-1 gene was detected by polymerase chain reaction-restriction fragment length polymerphim analysis. RESULTS: The frequencies of 4G/4G genotype and 4G allele of the PAI-1 gene were higher in the patient group (48.6% and 66.2%) than in the normal controls (22.4% and 47.1%) (P < 0.01). ThePAI-1 4G/4G genotype was significantly associated with endometrial hypoplasia in the infertile patients (OR=4.9, 95% CI: 2.10-10.12). CONCLUSION: The present findings suggest that the 4G/5G polymorphism of the PAI-1 gene was associated with endometrial hypoplasia in infertile patients.     

Identification of two mutations in a compound heterozygous child with dihydrolipoamide dehydrogenase deficiency

An infant girl with elevated blood lactate, pyruvate, and plasma branched-chain amino acids was diagnosed with dihydrolipoamide dehydrogenase (E3; dihydrolipoamide: NAD+ oxidoreductase, EC 1.8.1.4) deficiency. Activities of the pyruvate dehydrogenase complex and E3 from patient were 26 and 2% of controls in blood lymphocytes, and 11 and 14% in cultured skin fibroblasts, respectively. Western blot analysis demonstrated that the amount of E3 protein in fibroblasts from the patient and her father was about half of controls, while Northern blot analysis showed normal amounts of E3 RNA. DNA sequencing of cloned full-length E3 cDNAs from the patient revealed two mutations in separate alleles. One is a single base insertion of an extra adenine in the last codon of the leader peptide sequence (TAC-->TAAC) leading to a nonsense mutation which results in the premature termination of the precursor E3 polypeptide (Y35X). The other is a missense mutation due to substitution of guanine for adenine, causing an Arg-->Gly substitution at amino acid 460 of the mature protein (R460G) which triggers the loss of E3 activity probably by structural change in the E3 dimer. DNA sequencing of E3 cDNAs from the parents demonstrated that the nonsense mutation was inherited from the father and the missense mutation was inherited from the mother.      

Clamp loading,unloading and intrinsic stability of the PCNA, β and gp45 sliding clamps of human,E. coli and T4 replicases

Background: The high speed and processivity of replicative DNA polymerases reside in a processivity factor which has been shown to be a ring-shaped protein. This protein (‘sliding clamp’) encircles DNA and tethers the catalytic unit to the template. Although in eukaryotic, prokaryotic and bacteriophage-T4 systems, the processivity factors are ring-shaped, they assume different oligomeric states. The Escherichia coli clamp (the β subunit) is active as a dimer while the eukaryotic and T4 phage clamps (PCNA and gp45, respectively) are active as trimers. The clamp can not assemble itself on DNA. Instead, a protein complex known as a clamp loader utilizes ATP to assemble the ring around the primer-template. This study compares properties of the human PCNA clamp with those of E. coli and T4 phage. Results: The PCNA ring is a stable trimer down to a concentration below 100 nm (K_d ≈ 21 nm ). On DNA, the PCNA clamp slides freely and dissociates from DNA slowly (t_1/2 ≈ 24 min). β is more stable in solution (K_d < 60 pm ) and on DNA (t_1/2 ≈ 1 h) than PCNA which may be explained by its simpler oligomeric state. The T4 gp45 clamp is a much less stable trimer than PCNA (K_d ≈ 250 nm ) and requires association with the polymerase to stabilize it on DNA as observed previously. The consequence of this cooperation between clamp and polymerase is that upon finishing a template and dissociation of the polymerase from DNA, the gp45 clamp spontaneously dissociates from DNA without assistance. However, the greater stability of the PCNA and β clamps on DNA necessitates an active process for their removal. The clamp loaders (RF-C and γ complex) were also capable of unloading their respective clamps from DNA in the presence of ATP. Conclusions: The stability of the different clamps in solution correlates with their stability on DNA. Thus, the low stability of the T4 clamp explains the inability to isolate gp45 on DNA. The stability of the PCNA and β clamps predicts they will require an unloading factor to recycle them on and off DNA during replication. The clamp loaders of PCNA and β double as clamp unloaders presumably for the purpose of clamp recycling.     

The study of tuberculosis outbreak in a high school—Shanghai,China, 2017–2018

Journal of Public Health - To investigate the attack rate of active tuberculosis (TB) cases and detection rate of latent tuberculosis infection (LTBI) cases, and to identify possible factors...     

Machine Learning Algorithms to Predict Mortality and Allocate Palliative Care for Older Patients With Hip Fracture

ObjectivesTo evaluate a machine learning model designed to predict mortality for Medicare beneficiaries aged >65 years treated for hip fracture in Inpatient Rehabilitation Facilities (IRFs).DesignRetrospective design/cohort analysis of Centers for Medicare & Medicaid Services Inpatient Rehabilitation Facility–Patient Assessment Instrument data.Setting and ParticipantsA total of 17,140 persons admitted to Medicare-certified IRFs in 2015 following hospitalization for hip fracture.MeasuresPatient characteristics include sociodemographic (age, gender, race, and social support) and clinical factors (functional status at admission, chronic conditions) and IRF length of stay. Outcomes were 30-day and 1-year all-cause mortality. We trained and evaluated 2 classification models, logistic regression and a multilayer perceptron (MLP), to predict the probability of 30-day and 1-year mortality and evaluated the calibration, discrimination, and precision of the models.ResultsFor 30-day mortality, MLP performed well [acc = 0.74, area under the receiver operating characteristic curve (AUROC) = 0.76, avg prec = 0.10, slope = 1.14] as did logistic regression (acc = 0.78, AUROC = 0.76, avg prec = 0.09, slope = 1.20). For 1-year mortality, the performances were similar for both MLP (acc = 0.68, AUROC = 0.75, avg prec = 0.32, slope = 0.96) and logistic regression (acc = 0.68, AUROC = 0.75, avg prec = 0.32, slope = 0.95).Conclusion and ImplicationsA scoring system based on logistic regression may be more feasible to run in current electronic medical records. But MLP models may reduce cognitive burden and increase ability to calibrate to local data, yielding clinical specificity in mortality prediction so that palliative care resources may be allocated more effectively.     

大鼠不同程度的急性颅脑损伤后血糖浓度的变化及其预后

目的 :探讨大鼠不同程度的急性颅脑损伤后血糖浓度的变化及其与预后的关系。方法 :Wistar雄性大鼠 2 0只 ,随机分为 2组 ,A组 :将 5 0 0 g砝码由 35 cm高度自由下落打击大鼠头部 ;B组 :将 5 0 0 g砝码由 2 0 cm高度自由下落打击大鼠头部 ;设自身对照 ,分别测定不同伤情的两组动物伤前及伤后血糖浓度的变化及观察 2 4h内两组动物死亡情况。结果 :A、B组伤后测得的血糖值均显著高于正常值 (P <0 .0 5 ) ;且 A组伤后测得的血糖值又显著高于 B组 (P <0 .0 5 ) ;A组动物死亡 8只 ,B组死亡 1只。结论 :急性颅脑损伤后均有不同程度的血糖升高 ,而且颅脑损伤程度越重 ,血糖值越高 ,死亡率越高。     

醒脑静在重症一氧化碳中毒抢救中的临床应用

目的　探讨醒脑静对急性重症一氧化碳 (CO)中毒的催醒作用。方法　在急性重症CO中毒常规综合抢救中加入醒脑静并与常规方法进行对比研究。结果　醒脑静治疗组较常规治疗组清醒时间明显缩短 (P <0 .0 1)。结论　醒脑静可作为急性重症CO中毒病人综合抢救中常规用药。