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ABSTRACT-cell population resident within collagenase-treated, culture-processed bone fragments, which upon migration established a homogeneous population of MPCs. Additionally, we have introduced a system of culturing these MPCs that best supports and maintains their optimal differentiation potential during long-term culture expansion. When cultured as described, the trabecular bone-derived cells display stem cell-like capabilities, characterized by a stable undifferentiated phenotype as well as the ability to proliferate extensively while retaining the potential to differentiate along the osteoblastic, adipocytic, and chondrocytic lineages, even when maintained in long-term in vitro culture.

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Background: In response to the COVID-19 pandemic, hospitals in the United States were recommended to stop performing elective procedures. This stoppage has led to the cancellation of a large number of hip and knee arthroplasties. The effect of this on patients' physical mental and economic health is unknown. Methods: A survey was developed by the AAHKS Research Committee to assess pain, anxiety, physical function, and economic ability of patients to undergo a delayed operation. Six institutions conducted the survey to 360 patients who had to have elective hip and knee arthroplasty cancelled between March and July of 2020. Results: Patients were most anxious about the uncertainty of when their operation could be rescheduled. Although 85% of patients understood and agreed with the public health measures to curb infections, almost 90% of patients plan to reschedule as soon as possible. Age and geographic region of the patients affected their anxiety. Younger patients were more likely to have financial concerns and concerns about job security. Patients in the Northeast were more concerned about catching COVID-19 during a future hospitalization. Conclusions: Patients suffering from the pain of hip and knee arthritis continue to struggle with pain from their end-stage disease. They have anxiety about the COVID-19 pandemic. Few patients feel they will be limited financially and 90% want to have surgery as soon as possible. Age and physical location of the patients affect their causes for anxiety around their future surgery.

BackgroundNon-small cell lung cancer (NSCLC) is a heterogeneous group of disorders with a number of genetic and proteomic alterations. c-CBL is an E3 ubiquitin ligase and adaptor molecule important in normal homeostasis and cancer. We determined the genetic variations of c-CBL, relationship to receptor tyrosine kinases (EGFR and MET), and functionality in NSCLC.Methods and FindingsUsing archival formalin-fixed paraffin embedded (FFPE) extracted genomic DNA, we show that c-CBL mutations occur in somatic fashion for lung cancers. c-CBL mutations were not mutually exclusive of MET or EGFR mutations; however they were independent of p53 and KRAS mutations. In normal/tumor pairwise analysis, there was significant loss of heterozygosity (LOH) for the c-CBL locus (22%, n = 8/37) and none of these samples revealed any mutation in the remaining copy of c-CBL. The c-CBL LOH also positively correlated with EGFR and MET mutations observed in the same samples. Using select c-CBL somatic mutations such as S80N/H94Y, Q249E and W802* (obtained from Caucasian, Taiwanese and African-American samples, respectively) transfected in NSCLC cell lines, there was increased cell viability and cell motility.ConclusionsTaking the overall mutation rate of c-CBL to be a combination as somatic missense mutation and LOH, it is clear that c-CBL is highly mutated in lung cancers and may play an essential role in lung tumorigenesis and metastasis.

Adenoviral oncolytic virotherapy represents an attractive treatment modality for central nervous system (CNS) neoplasms. However, successful application of virotherapy in clinical trials has been hampered by inadequate distribution of oncolytic vectors. Neural stem cells (NSCs) have been shown as suitable vehicles for gene delivery because they track tumor foci. In this study, we evaluated the capability of NSCs to deliver a conditionally replicating adenovirus (CRAd) to glioma. We examined NSC specificity with respect to viral transduction, migration and capacity to deliver a CRAd to tumor cells. Fluorescence-activated cell sorter (FACS) analysis of NSC shows that these cells express a variety of surface receptors that make them amenable to entry by recombinant adenoviruses. Luciferase assays with replication-deficient vectors possessing a variety of transductional modifications targeted to these receptors confirm these results. Real-time PCR analysis of the replication profiles of different CRAds in NSCs and a representative glioma cell line, U87MG, identified the CRAd-Survivin (S)-pk7 virus as optimal vector for further delivery studies. Using in vitro and in vivo migration studies, we show that NSCs infected with CRAd-S-pk7 virus migrate and preferentially deliver CRAd to U87MG glioma. These results suggest that NSCs mediate an enhanced intratumoral distribution of an oncolytic vector in malignant glioma when compared with virus injection alone.

The relA gene product determines the level of (p)ppGpp, the effector nucleotides of the bacterial stringent response that are also involved in the regulation of other functions, like antibiotic production and quorum sensing. In order to explore the possible involvement of relA in the regulation of virulence of Vibrio cholerae, a relA homolog from the organism (relA VCH ) was cloned and sequenced. The relA VCH gene encodes a 738-aminoacid protein having functions similar to those of other gram-negative bacteria, including Escherichia coli. A ⌬relA::kan allele was generated by replacing ϳ31% of the open reading frame of wild-type relA of V. cholerae El Tor strain C6709 with a kanamycin resistance gene. The V. cholerae relA mutant strain thus generated, SHK17, failed to accumulate (p)ppGpp upon amino acid deprivation. Interestingly, compared to the wild type, C6709, the mutant strain SHK17 exhibited significantly reduced in vitro production of two principal virulence factors, cholera toxin (CT) and toxin-coregulated pilus (TCP), under virulence gene-inducing conditions. In vivo experiments carried out in rabbit ileal loop and suckling mouse models also confirmed our in vitro results. The data suggest that (p)ppGpp is essential for maximal expression of CT and TCP during in vitro growth, as well as during intestinal infection by virulent V. cholerae. Northern blot and reverse transcriptase PCR analyses indicated significant reduction in the transcript levels of both virulence factors in the relA mutant strain SHK17. Such marked alteration of virulence phenotypes in SHK17 appears most likely to be due to down regulation of transcript levels of toxR and toxT, the two most important virulence regulatory genes of V. cholerae. In SHK17, the altered expression of the two outer membrane porin proteins, OmpU and OmpT, indicated that the relA mutation most likely affects the ToxR-dependent virulence regulatory pathway, because it had been shown earlier that ToxR directly regulates their expression independently of ToxT.Vibrio cholerae is a facultative anaerobic gram-negative bacterium and the causative agent of the severe diarrheal disease cholera. In addition to residing temporarily in the intestinal lumen of humans during the diseased state, V. cholerae has its natural niche in the aquatic environment, residing in the freeliving aquatic flora found in estuarine areas and in association with crustaceans and mollusks (25). The strains of V. cholerae that cause epidemic cholera belong to serogroups O1 and O139 (3, 4, 28, 41, 50). The O1 serogroup is again divided into two biotypes, classical and El Tor (28). Strains other than O1 and O139 are known as non-O1/non-O139 vibrios.A pathogen in its natural environment and host-associated state is subjected to a plethora of stresses, such as fluctuations in pH, salinity, osmolarity, oxygen tension, temperature, and nutritional availability. These offer selective pressure to a bacterium, eliciting various adaptive responses for its survival. The adaptive response to nutritional stre...

Frequenin, a Ca 2؉ -binding protein, has previously been implicated in the regulation of neurotransmission, possibly by affecting ion channel function. Here, we provide direct evidence that frequenin is a potent and specific modulator of Kv4 channels, the principal molecular components of subthreshold activating A-type K ؉ currents.