Effect of Dopants on Epitaxial Growth of Silicon Nanowires

We investigated the effects of dopants on epitaxial growth of Si NWs, with an emphasis on synthesizing vertical epitaxial Si NW arrays on Si (111) substrates. We found that addition of boron with a B:Si feed-in atomic ratio greater than 1:1000 improved the percentage of Si NWs grown along the vertical direction to more than 90%, compared to 38% for i-Si NWs. We also demonstrated a stemmed growth strategy and achieved a 93% percentage of i-Si NW segments along the vertical direction on Si substrates. In summary, our study opens up potential for using chemical synthesized vertical Si NW arrays integrated on Si substrates for large-scale applications

Impact of the COVID-19 Pandemic on the Field of Orthopedics

During the COVID-19 pandemic, countries all over the world suffered from different kinds of service disruption or reduction in the field of orthopedics with or without lockdowns. The consequences include no restriction, partial disruption, overburden of medical services and complete shutdown of clinical practices. This chapter systematically reviews the current published literature on the global impact of COVID-19 on the field of orthopedics through multiple aspects, including educational impact, service volume impact, workload impact, personal practice change, psychological impact, and impact on orthopedic research. The rates of all surgeries and elective surgeries decreased by 15.6%–49.4% and 43.5–100%, respectively. The overall impact was attributable to the staff redeployment in response to the pandemic. Therefore, it is important to maintain a flexible allocation of manpower and more sufficient and reservable staffing measures in case of emergency staff shortages. Orthopedic surgeons are suggested to prepare proper preventive strategies and set up special equipment and places for regular telemedicine for virtual consultations or virtual teaching. It can be expected that the integration of the different experiences of global countries from the impact of COVID-19 may help us to face possible similar impacts in the future

Nidogen Plays a Role in the Regenerative Axon Growth of Adult Sensory Neurons Through Schwann Cells

We previously reported that nidogen is an extracellular matrix protein regulating Schwann cell proliferation and migration. Since Schwann cells play a critical role in peripheral nerve regeneration, nidogen may play a role in it via regulation of Schwann cells. Here, we demonstrate direct evidence that nidogen induces elongation of regenerative axon growth of adult sensory neurons, and that the effect is Schwann cell dependent. Continuous infusion of recombinant ectodomain of tumor endothelial marker 7, which specifically blocks nidogen function in Schwann cells, suppressed regenerative neurite growth in a sciatic nerve axotomy model. Taken together, it is likely that nidogen is required for proper regeneration of peripheral nerves after injury

A Case of Pulmonary Vein Tumor Presenting as a Left Atrial Mass

Primary cardiac tumors are extremely rare and can originate within the heart or be the result of tumor spread from other sites. We report a female patient with a pulmonary vein tumor extending into the left atrium that had a suspicious primary malignant origin with a sacral metastatic carcinoma. The patient was admitted complaining of pain in her buttock area as a result of a sacral tumor. It was believed that the sacral tumor was a metastasis from the imaging study and clinical manifestation. The primary malignant origin was evaluated. The chest CT showed a left atrium thrombus-like lesion without a pulmonary abnormality. After a transesophageal echocardiogram, the patient was diagnosed with a pulmonary vein tumor extending to the left atrium. The patient was given palliative radiotherapy for the sacral pain. Initially, the clinical impression was a metastatic sacral tumor with a thromboembolism of the left atrium. However, this patient was finally diagnosed with a pulmonary vein tumor with a left atrium extension by a transesophageal echocardiogram

Leiomyosarcoma Arising from the Blind End of a Bifid Renal Pelvis

Sarcoma of the kidney is a rare condition. Leiomyosarcoma is the most common of the kidney sarcomas. Renal leiomyosarcoma usually originates from the smooth muscle layers of the kidney, for example, the renal capsule and renal vessels. Renal pelvis neoplasms, however, are primarily transitional cell carcinomas, and renal pelvis leiomyosarcomas are extremely uncommon. Renal pelvis leiomyosarcoma has never been reported in Korea. Moreover, no more than 10 cases have been reported internationally. However, none of these were associated with kidney abnormalities. Here we describe a case of leiomyosarcoma that originated from the blind end of a bifid renal pelvis

A Polymorphism (rs1801018, Thr7Thr) of BCL2 is Associated with Papillary Thyroid Cancer in Korean Population

ObjectivesAmong the apoptosis signals, B-cell CLL/lymphoma 2 (BCL2) is a well-known regulator of apoptosis with anti-apoptotic properties. We investigated here whether single nucleotide polymorphisms (SNPs) of the BCL2 were associated with host susceptibility of papillary thyroid cancer (PTC) occurrence and clinicopathologic parameters.MethodsNinety-two PTC patients and 222 control subjects were recruited. One promoter SNP (rs2279115, -938A/C) and one synonymous SNP (rs1801018, Thr7Thr) in the BCL2 gene were selected and genotyped using direct sequencing. Multiple logistic regression models were performed to evaluate odds ratios, 95% confidence intervals, and P-values.Resultsrs1801018 of the BCL2 gene was not associated with the development of PTC. In the clinicopathologic features, rs1801018 SNP was associated with the number and location. The G allele frequency of rs1801018 in PTC patients with multifocality (13.3%) was about four-fold higher than that in PTC patients with unifocality (3.4%). The G allele frequency of rs1801018 in PTC patients with both lobes (15.4%) was increased by about five-fold, compared to PTC patients with one lobe (3.2%).ConclusionThe results suggest that synonymous SNP rs1801018 and the G allele of the BCL2 gene may be associated with the multifocality and bilaterality of PTC in Korean population

Use of Cytochrome c Oxidase Subunit I (COI) Nucleotide Sequences for Identification of the Korean Luciliinae Fly Species (Diptera: Calliphoridae) in Forensic Investigations

Blowflies, especially species belonging to the subfamily Luciliinae, are the first insects to lay eggs on corpses in Korea. Fast and accurate species identification has been a key task for forensic entomologists. Because conventional morphologic identification methods have many limitations with respect to forensic practice, molecular methods have been proposed to identify fly species of forensic importance. To this end, the authors amplified and sequenced the full length of the cytochrome c oxidase subunit I (COI) gene of the Luciliinae fly species collected in Korea. The results showed the COI sequences are instrumental in identifying Luciliinae fly species. However, when compared with previously reported data, considerable inconsistencies were noted. Hemipyrellia ligurriens data in this study differed significantly from two of the five pre-existing data. Two closely related species, Lucilia illustris and Lucilia caesar, showed an overlap of COI haplotypes due to four European sequences. The results suggest that more individuals from various geographic regions and additive nuclear DNA markers should be analyzed, and morphologic identification keys must be reconfirmed to overcome these inconsistencies

Treatment Outcomes with CHOP Chemotherapy in Adult Patients with Hemophagocytic Lymphohistiocytosis

The objective of the current study was to investigate the treatment outcomes for the use of cyclophosphamide, adriamycin, vincristine, and prednisolone (CHOP) chemotherapy in adult patients with hemophagocytic lymphohistiocytosis (HLH). Seventeen HLH patients older than 18 yr of age were treated with CHOP chemotherapy. A response evaluation was conducted for every two cycles of chemotherapy. With CHOP chemotherapy, complete response was achieved for 7/17 patients (41.2%), a partial response for 3/17 patients (17.6%), and the overall response rate was 58.8%. The median response duration (RD) was not reached and the 2-yr RD rate was 68.6%, with a median follow-up of 100 weeks. Median overall survival (OS) was 18 weeks (95% CI, 6-30 weeks) and the 2-yr OS rate was 43.9%. Reported grade 3 or 4 non-hematological toxicities were increased serum liver enzyme levels and stomatitis. Grade 3 or 4 hematological toxicities were leukopenia (50.8%), anemia (20%), and thrombocytopenia (33.9%). Neutropenic fever was observed in 21.6% of patients (14/65 cycles), and most of the cases were resolved with supportive care including treatment with broad-spectrum antibiotics. CHOP chemotherapy seems to be effective in adult HLH patients and the toxicities are manageable