Social Media Use Among Arthroscopic and Orthopaedic Sports Medicine Specialists Varies by Subspeciality.

Purpose: To evaluate active social media use among members of the Arthroscopy Association of North America (AANA) and investigate differences in social media use based on joint-specific subspecialization. Methods: The AANA membership directory was queried to identify all active, residency-trained orthopaedic surgeons within the United States. Sex, practice location, and academic degrees earned were recorded. Google searches were conducted to find professional Facebook, Twitter, Instagram, LinkedIn, and YouTube accounts along with institutional and personal websites. The primary outcome was the Social Media Index (SMI) score, an aggregate measure of social media use across key platforms. A Poisson regression model was constructed to compare SMI scores across joint-specific subspecializations: knee, hip, shoulder, elbow, foot & ankle, and wrist. Specialization in the treatment of each joint was collected using binary indicator variables. Since surgeons were specialized in multiple groups, comparisons were made between those who do and do not treat each joint. Results: In total, 2,573 surgeons within the United States met the inclusion criteria. 64.7% had ownership of at least 1 active account, with an average SMI score of 2.29 ± 1.59. Western practicing surgeons had a significantly greater presence on at least 1 website than those in the Northeast (P = .003, P < .001) and South (P = .005, P = .002). Social media use by knee, hip, shoulder, and elbow surgeons was greater relative to those who did not treat those respective joints (P < .001 for all). Poisson regression analysis demonstrated that knee, shoulder, or wrist specialization was a significant positive predictor of a greater SMI score (P ≤ .001 for all). Foot & ankle specialization was a negative predictor (P < .001), whereas hip (P = .125) and elbow (P = .077) were not significant predictors. Conclusions: Social media use widely varies across joint subspecialties within orthopaedic sports medicine. Knee and shoulder surgeons had a greater social media use than their counterparts, whereas foot & ankle surgeons had the lowest social media use. Clinical Relevance: Social media is a vital source of information for both patients and surgeons, providing a means for marketing, networking, and education. It is important to identify variations in social media use by orthopaedic surgeons by subspecialty and explore the differences.

Safety of rapid inpatient methadone initiation protocol: A retrospective cohort study.

BACKGROUND: Current methadone titration guidelines recommend low initial doses (15-40 mg) and slow increases (10-20 mg every 3 to 7 days) to prevent dose accumulation and oversedation until reaching a target therapeutic dose between 60 and 120 mg. These guidelines were created primarily for outpatient settings in the pre-fentanyl era. Methadone initiations are becoming more common in hospitals, but no titration guidelines exist specific to this treatment setting, which has capacity for increased monitoring. Our objective was to assess the safety of rapid inpatient methadone initiation with regard to mortality, overdose, and serious adverse outcomes both in-hospital and postdischarge. METHODS: This is a retrospective, observational, cohort study conducted at an urban, academic medical center in the United States. We queried our electronic medical record for hospitalized adults with moderate to severe opioid use disorder admitted between July 1, 2018, and November 30, 2021. Included patients were rapidly initiated on methadone with 30 mg as the initial dose and 10 mg increases daily until reaching 60 mg. The study extracted thirty-day post-discharge opioid overdose and mortality data from the CRISP database. RESULTS: Twenty-five hospitalized patients received rapid methadone initiation during the study period. The study had no major adverse events including in-hospital or thirty-day post-discharge overdoses or deaths. The study did have two instances of sedation, but neither led to methadone dose holds. There were no instances of QTc prolongation. The study had one patient-directed discharge. CONCLUSIONS: This study demonstrated that a small subset of hospitalized patients tolerated rapid methadone initiation. More rapid titrations can be utilized in a monitored inpatient setting to retain patients in the hospital and allow providers to account for increased tolerance in the fentanyl era. Guidelines should be updated to reflect the capabilities of inpatient settings to safely initiate and rapidly titrate methadone. Further work should determine optimal methadone initiation protocols in the fentanyl era.

Advanced non-small cell lung cancer treated with palliative systemic therapy complicated by calvarial metastasis: a case report.

Background: Bony metastases are often seen in advanced cancers and lead to deterioration in patient quality of life with common complications of pain, bone fractures, and hypercalcemia. While most sites of metastasis to bone are observed in the axial skeleton from patients with a primary lung, breast or prostate cancer, metastases to the calvarium from lung cancer are less common, and thus less likely to be identified and managed. Case Description: A 69-year-old Caucasian female with advanced non-small cell lung cancer (NSCLC) presented with worsening symptoms of widespread body pain, fatigue, and weight loss. Physical examination was remarkable for a palpable protrusion on the patient's head. Imaging revealed a parieto-occipital calvarial lesion, a likely metastasis from her lung cancer. A previously performed CT-guided lung biopsy was evaluated for actionable tumor markers to allow for more specific and efficacious line of treatments; the patient's tumor had lacked any notable gene mutations. The treatment plan included radiotherapy, combined immunotherapy and chemotherapy consisting of pembrolizumab, pemetrexed, and carboplatin. Despite the treatment, the patient's skull lesion had continued to grow, and her overall condition deteriorated to the point where she required hospice. Conclusions: Given the unique location of calvarial metastases, early detection appears to correlate with improving patient outcomes and quality of life. A multimodal approach with a high index of suspicion is essential for diagnosing and managing rare presentations of metastatic disease.

Simple and field amenable loop-mediated isothermal amplification-lateral flow dipstick assay for detection of west Nile virus in human clinical samples.

AIM: West Nile encephalitis caused by infection with the West Nile virus (WNV) is endemic in many regions of the world and is a global public health threat. The aim of this report was to develop a method using colorimetry-based reverse-transcription loop-mediated isothermal amplification (cRT-LAMP) and RT-LAMP combined with lateral-flow dipstick (LFD) for rapidly detecting WNV in low-infrastructure settings. METHODS AND RESULTS: The primers for the cRT-LAMP and RT-LAMP-LFD assays were designed based on env gene of the WNV. Primers concentration, temperature and time were optimized for cRT-LAMP and RT-LAMP-LFD. The diagnostic performance of the cRT-LAMP and RT-LAMP-LFD assays was evaluated using human serum samples from 110 patients who were clinically suspected to be infected with WNV. The RT-LAMP was performed in a heating block at 63°C for 40 min. The LAMP amplicons were visible in the lateral-flow dipstick within 5 min. The detection limit of the developed cRT-LAMP and RT-LAMP-LFD assays was 10 copies and this assay showed a high degree of specificity for WNV. Compared with quantitative real-time RT-PCR assay, the kappa value of cRT-LAMP and RT-LAMP-LFD were 0.970. CONCLUSIONS: These results showed that the newly developed WNV-specific cRT-LAMP and RT-LAMP-LFD assays can be employed as an alternative method for screening of WN-suspected human samples. The results revealed that the assay could potentially identify the virus without interference from human serum samples. Collectively, all results revealed that cRT-LAMP and RT-LAMP-LFD assays offer a suitable field-based diagnosis of WNV. SIGNIFICANCE AND IMPACT OF THE STUDY: The cRT-LAMP and LAMP-LFD platform for the detection of WNV is rapid, accurate and simple-to-perform. Our present method has not only a short turnaround time but also avoided cross-contamination problem. Moreover, the use of simple lateral flow dipsticks broadens its application potential for the point-of-care use in resource-limited settings during outbreak situations. To the best of our knowledge, this is the first report for the development of cRT-LAMP and LAMP-LFD assays for rapid, simple, specific and sensitive detection of WNV using human clinical samples and EvaGreen dye.

Motor Cortex Response to Pleasant Odor Perception and Imagery: The Differential Role of Personality Dimensions and Imagery Ability.

Background: Neuroimaging studies have shown a complex pattern of brain activation during perception of a pleasant odor and during its olfactory imagery. To date, little is known regarding changes in motor cortex excitability during these tasks. Bergamot essential oil (BEO) is extensively used in perfumes and cosmetics for its pleasantness. Therefore, to further our understanding of the human sense of smell, this study aimed to investigate the effect of perception and imagery of a pleasant odor (BEO) on motor cortex using Transcranial magnetic stimulation (TMS). Materials and Methods: We examined the primary motor cortex (M1) excitability during perception of a pleasant odor (BEO) or perception of odorless saline (experiment 1). Furthermore, we tested the effect of olfactory imagery (OI) of BEO on corticospinal excitability (experiment 2). The increase in motor evoked potential (MEP) amplitude was correlated with personality dimensions scores, pleasantness, vividness, and general imagery ability. Results: The results indicate that the corticospinal excitability changed after both perception and imagery of a pleasant odor (BEO). The correlation analysis shows an association with neuroticism personality trait (experiment 1) and with general olfactory imagery ability (experiment 2). Conclusion: Both perception of a pleasant odor and its olfactory imagery modulate motor cortex excitability. The enhanced brain activation is affected by specific individual characteristics. Overall, our findings provide physiological evidence for a complex interaction between the olfactory and motor systems.

Low-dose ketamine as an adjuvant for pain control in a cancer patient: a case report.

Cancer patients often suffer from pain related problems such as under-treatment of pain, ineffective and persistent opioid administration as well as adverse opioid use outcomes. There is a growing need for non-opioid analgesic alternatives for patients undergoing treatment for obstinate pain. Ketamine is a fast-acting N-methyl-D-aspartate (NMDA) receptor antagonist that has been emerging as an effective medication for pain alleviation. While protocols have been established for the use of Low-Dose Ketamine (LDK) for post-operative pain, there is growing evidence for using LDK as a clinical alternative to opioids in a palliative care setting. This case study involves monitoring the efficacy of LDK treatment in combination with opioid analgesics in a cancer patient in a hospital setting. This is a very selected case of a patient with Metastatic Prostate Cancer (Gleason 9 Adenocarcinoma) where LDK was shown to be efficacious at reducing pain when opioids and standard pain medications were not satisfactory. While the study involved using a relatively novel pharmacological protocol and close patient monitoring, the patient reported a sustained reduction in pain level based on the Numerical Rating Scale for months after the termination of LDK infusions. Moreover, the treatment also resulted in a reduction of total opioid usage after the addition of LDK. Although additional research is needed to ascertain optimal dosing schedules and route of Ketamine, given these promising findings, Ketamine may be a useful option for improving the treatment of refractory pain in patients with cancer and a good tool in palliative medicine for treating neoplastic pain.

The Opioid Crisis: How to Lessen the Burden on Emergency Departments by At-risk Populations.

Background The opioid crisis in the United States of America has been worsening due to previous sharp increases in opioid prescriptions and a lack of resources available to those affected. Emergency departments (ED) across the nation have been exhausted with a constant influx of patients related to opioid-related issues. Because of limited resources, it is crucial to efficiently distribute rehabilitation and mental wellness efforts amongst those most susceptible to opioid abuse. By identifying common environments and characteristics of the population presenting to ED's for opioid-related issues, we can (1) lessen the economic burden on the healthcare system while (2) increasing the rate of successful treatment for those affected by opioid addiction. Methods Data was obtained regarding ED visits for opioid-related issues at the level of all 50 states from the Healthcare Cost and Utilization Project's (HCUP) State Emergency Department Databases (SEDD) and nationally from the Nationwide Emergency Department Sample (NEDS). Rates of ED admissions for opioid-related issues were statistically analyzed to identify characteristics of the population that are most at risk for presenting to the ED for opioid-related issues. Results Statistical analysis showed residents of Large Metropolitan areas (M=351.94, p=0.022, CI±42.89), those earning incomes below the 25th percentile (M=359.14, p=0.008, CI ±61.39), and 25-44-year-old population (M=456.71, p=0.001, CI±27.01) to be the most likely subset of the population to report to the ED for opioid-use issues. Conversely, those earning incomes above the 75th percentile were significantly less likely to utilize ED's for opioid-related issues (M=143.10, p=0.026, CI±0.026). Conclusion Results demonstrated that patients between the ages of 25 and 44 were more likely to develop opioid use disorders. This provides an opportunity to educate this population via opioid education centers. Additionally, residents of Large Metropolitan areas would benefit from naloxone distribution centers. Lastly, higher income levels appear to be related to a decrease in ED presentation for opioid abuse. This provides evidence for medication-assisted therapy (MAT) to be provided by low-income insurance plans.

Treating Bell's Palsy With Osteopathic Manipulative Medicine: A Case Report.

Bell's palsy (BP) occurs when the facial nerve (CN VII) is swollen, inflamed, or compressed, resulting in facial weakness or paralysis; etiology is unknown. BP patients often succumb to a decreased quality of life due to the inability to make facial expressions, increased sensitivity to auditory stimuli, and dysregulation in tear and saliva production. Despite conventional examination and therapy options, the syndrome is majorly regarded as idiopathic and left unresolved for many patients. In this case of a patient with BP, treatment with osteopathic manipulative treatment (OMT) which focused on restoring a normal structure-function relationship resolved the patient's symptoms. The osteopathic manipulative procedures utilized findings from an osteopathic structural exam and addressed those somatic dysfunctions with OMT. The authors report that the patient's symptoms improved after the application of OMT and without the use of pharmaceuticals. The results of the case study suggest that treating BP with OMT can rapidly improve symptoms and can be used without or concurrently with other treatment modalities, if applicable. Patient's consent for this case report was obtained in written and verbal form.

Polymerase Spiral Reaction Assay for Rapid and Real Time Detection of West Nile Virus From Clinical Samples.

West Nile virus (WNV) is a mosquito-borne virus of public health importance. Currently, there is no FDA approved vaccine available against WNV infection in humans. Therefore, the early diagnosis of the WNV infection is important for epidemiologic control and timely clinical management in areas where multiple Flaviviruses are endemic. The present study aimed to develop reverse transcription polymerase spiral reaction (RT-PSR) assay that rapidly and accurately detects the envelope (env) gene of WNV. RT-PSR assay was optimized at 63°C for 60 min using real-time turbidimeter or visual detection by the addition of SYBR Green I dye. The standard curve for RT-PSR assay was generated using the 10-fold serial dilutions of in vitro transcribed WNV RNA. To determine the detection limit of RT-PSR assay, an amplified product of conventional RT-PCR was in vitro transcribed as per standard protocol. The detection limit of the newly developed RT-PSR assay was compared with that of conventional RT-PCR and CDC reported TaqMan real-time RT-PCR using a serial 10-fold dilution of IVT WNV RNA. The detection limit of RT-PSR was found to be 1 RNA copy, which is 100-fold higher than that of conventional RT-PCR (100 copies). This suggests that RT-PSR assay is a valuable diagnostic tool for rapid and real-time detection of WNV in acute-phase serum samples. The assay was validated with a panel of 107 WNV suspected human clinical samples with signs of acute posterior uveitis and onset of febrile illness. Out of 107 samples, 30 were found positive by RT-PSR assay. The specificities of the selected primer sets were established by the absence of cross-reactivity with other closely related members viruses of the Flaviviruses, Alphaviruses, and Morbilliviruses groups. No cross-reactivity was observed with other viruses. To best of our knowledge, this is the first report describing the RT-PSR assay for the detection of RNA virus (WNV) in clinical samples. RT-PSR is a high throughput method and more than 30 reactions can be run at once in real-time turbidimeter. PSR assay has potential to be used for a rapid screening of large number of clinical samples in endemic areas during an outbreak.

Exploring the Gender Difference and Predictors of Perceived Stress among Students Enrolled in Different Medical Programs: A Cross-Sectional Study.

Female medical students seem to experience higher level of perceived stress. Moreover, there is a lack of research examining perceived stress in students enrolled in different medical programs. We analyzed the association between temperament traits, optimism, self-esteem, and perceived stress of students pursuing a Doctor of Medicine (MD) degree and students pursuing a Doctor of Podiatric Medicine (DPM) degree. A cross-sectional study was conducted of two cohorts: allopathic medical students (N = 154) and the podiatric medical students (N = 150). Students anonymously completed the Perceived Stress Scale (PSS-10), Temperament Evaluation of Memphis, Pisa, Paris, and San Diego Auto Questionnaire (TEMPS-A), Rosenberg Self-Esteem Scale, and Life Orientation Test-Revised (LOT-R). We analyzed differences in the two cohort of students and predictors of perceived stress. There were no differences in the overall perception of stress between both cohorts (allopathic medical students: 18.83 ± 0.56; podiatric medical students: 19.3 ± 0.72; p = 0.4419). Women reported higher perceived stress in both programs (allopathic medical students: p = 0.0.038; podiatric medical students: p = 0.0.038). In both allopathic and podiatric medical students, the cyclothymic temperaments and anxious traits were positive predictors while hyperthymic temperaments and optimism traits were negative predictors of perceived stress. The level of perceived stress experienced by students pursuing different doctoral degrees in healthcare is similar. Regardless of the curriculum differences, female students experience higher perceived stress and there is evidence for similarities in predictors amongst allopathic and podiatric medical students.

Development and Evaluation of Real-Time Reverse Transcription Recombinase Polymerase Amplification Assay for Rapid and Sensitive Detection of West Nile Virus in Human Clinical Samples.

West Nile virus (WNV) causes West Nile fever and encephalitis worldwide. Currently, there are no effective drugs or vaccines available in the market to treat WNV infection in humans. Hence, it is of paramount importance to detect WNV early for the success of the disease control programs and timely clinical management in endemic areas. In the present paper, we report the development of real-time reverse transcription recombinase polymerase amplification (RT-RPA) assay for rapid and real-time detection of WNV targeting the envelope (env) gene of the virus. The RPA reaction was performed successfully at 39°C for 15 min in a real-time thermal cycler. The sensitivity of this assay was found similar to that of the quantitative real-time RT PCR (RT-qPCR) assay, which could detect 10 copies of the gene. The efficacy of the assay was evaluated with a panel of 110 WN suspected human samples showing the signs of retinitis, febrile illness and acute posterior uveitis. In comparison with RT-qPCR, RT-RPA showed a specificity of 100% (CI, 95.07-100%) and sensitivity of 96.15% (CI, 80.36-99.90%) with a negative (NPV) and positive predictive value (PPV) of 98.65 and 100%, respectively. The level of agreement between RT-RPA and reference RT-qPCR assay was shown to be very high. The turnaround time of real-time RPA assay is about 10-20 times faster than the RT-qPCR, which confirms its utility in the rapid and sensitive diagnosis of WNV infection. To the best of our knowledge, this is the first report which deals with the development of real-time RT-RPA assay for simple, rapid, sensitive, and specific detection of WNV in human clinical samples. The present RT-RPA assay proves to be a powerful tool that can be used for the rapid diagnosis of a large number of patient samples in endemic settings.

Effects of taurine acute intake on cortical excitability and post-exercise facilitation: A TMS study.

Taurine (TAU) is one of the most abundant amino acids in the brain. It has many important physiological functions. The effects of TAU supplementation on brain function need to be further characterized in humans. The purpose of this study was to investigate whether a single dose of Taurine (TAU) intake would modulate corticospinal excitability and post-exercise facilitation (PEF) of the motor evoked potentials (MEP).

The possible roles of B-cell novel protein-1 (BCNP1) in cellular signalling pathways and in cancer.

B-cell novel protein-1 (BCNP1) or Family member of 129C (FAM129C) was identified as a B-cell-specific plasma-membrane protein. Bioinformatics analysis predicted that BCNP1 might be heavily phosphorylated. The BCNP1 protein contains a pleckstrin homology (PH) domain, two proline-rich (PR) regions and a Leucine Zipper (LZ) domain suggesting that it may be involved in protein-protein interactions. Using The Cancer Genome Atlas (TCGA) data sets, we investigated the correlation of alteration of the BCNP1 copy-number changes and mutations in several cancer types. We also investigated the function of BCNP1 in cellular signalling pathways. We found that BCNP1 is highly altered in some types of cancers and that BCNP1 copy-number changes and mutations co-occur with other molecular alteration events for TP53 (tumour protein P53), PIK3CA (Phosphatidylinositol-4,5-Bisphosphate 3-Kinase, Catalytic Subunit Alpha), MAPK1 (mitogen-activated protein kinase-1; ERK: extracellular signal regulated kinase), KRAS (Kirsten rat sarcoma viral oncogene homolog) and AKT2 (V-Akt Murine Thymoma Viral Oncogene Homolog 2). We also found that PI3K (Phoshoinositide 3-kinase) inhibition and p38 MAPK (p38 mitogen-activated protein kinase) activation leads to reduction in phosphorylation of BCNP1 at serine residues, suggesting that BCNP1 phosphorylation is PI3K and p38MAPK dependent and that it might be involved in cancer. Its degradation depends on a proteasome-mediated pathway.

Effect of purified fractions from cell culture supernate of high-density pre-B acute lymphoblastic leukemia cells (ALL3) on the growth of ALL3 cells at low density.

The mechanisms underlying the aberrant growth and interactions between cells are not understood very well. The pre-B acute lymphoblastic leukemia cells directly obtained from an adult patient grow very poorly or do not grow at all at low density (LD), but grow better at high starting cell density (HD). We found that the LD ALL3 cells can be stimulated to grow in the presence of diffusible, soluble factors secreted by ALL3 cells themselves growing at high starting cell density. We then developed a biochemical purification procedure that allowed us to purify the factor(s) with stimulatory activity and analyzed them by nanoliquid chromatography-tandem mass spectrometry (nanoLC-MS/MS). Using nanoLC-MS/MS we have identified several proteins which were further processed using various bioinformatics tools. This resulted in eight protein candidates which might be responsible for the growth activity on non-growing LD ALL3 cells and their involvement in the stimulatory activity are discussed.

AFM study shows prominent physical changes in elasticity and pericellular layer in human acute leukemic cells due to inadequate cell-cell communication.

Biomechanical properties of single cells in vitro or ex vivo and their pericellular interfaces have recently attracted a lot of attention as a potential biophysical (and possibly prognostic) marker of various diseases and cell abnormalities. At the same time, the influence of the cell environment on the biomechanical properties of cells is not well studied. Here we use atomic force microscopy to demonstrate that cell-cell communication can have a profound effect on both cell elasticity and its pericellular coat. A human pre-B p190BCR/ABL acute lymphoblastic leukemia cell line (ALL3) was used in this study. Assuming that cell-cell communication is inversely proportional to the distance between cells, we study ALL3 cells in vitro growing at different cell densities. ALL3 cells demonstrate a clear density dependent behavior. These cells grow very well if started at a relatively high cell density (HD, >2 × 105 cells ml-1) and are poised to grow at low cell density (LD, <1 × 104 cells ml-1). Here we observe ∼6× increase in the elastic (Young's) modulus of the cell body and ∼3.6× decrease in the pericellular brush length of LD cells compared to HD ALL3 cells. The difference observed in the elastic modulus is much larger than typically reported for pathologically transformed cells. Thus, cell-cell communication must be taken into account when studying biomechanics of cells, in particular, correlating cell phenotype and its biophysical properties.

Exosome mediated growth effect on the non-growing pre-B acute lymphoblastic leukemia cells at low starting cell density.

Tumors contain heterogeneous cell populations and achieve dominance by functioning as collective systems. The mechanisms underlying the aberrant growth and interactions between cells are not very well understood. The pre-B acute lymphoblastic leukemia cells we studied were obtained directly from a patient with Ph+ ALL. A new Ph+ ALL cell line (ALL3) was established from the leukemic cells growing as ascitic cells in his pleural fluid. The patient died of his disease shortly after the cells were obtained. ALL3 cells grow well at high cell densities (HD), but not at low cell densities. ALL3 cells are very sensitive to potent tyrosine kinase inhibitors (TKIs) such as Dasatinib and PD166325, but less sensitive to AMN 107, Imatinib, and BMS 214662 (a farnesyl transferase inhibitor). Here, we show that the growth of the LD ALL3 cells can be stimulated to grow in the presence of diffusible, soluble factors secreted by ALL3 cells themselves growing at high density. We also show that exosomes, part of the secretome components, are also able to stimulate the growth of the non-growing LD ALL3 cells and modulate their proliferative behavior. Characterization of the exosome particles also showed that the HD ALL3 cells are able to secret them in large quantities and that they are capable of inducing the growth of the LD ALL3 cells without which they will not survive. Direct stimulation of non-growing LD ALL3 cells using purified exosomes shows that the ALL3 cells can also communicate with each other by means of exchange of exosomes independently of direct cell-cell contacts or diffusible soluble stimulatory factors secreted by HD ALL3 cells.

Defective quorum sensing of acute lymphoblastic leukemic cells: evidence of collective behavior of leukemic populations as semi-autonomous aberrant ecosystems.

Quorum sensing (QS) is a generic term used to describe cell-cell communication and collective decision making by bacterial and social insects to regulate the expression of specific genes in controlling cell density and other properties of the populations in response to nutrient supply or changes in the environment. QS mechanisms also have a role in higher organisms in maintaining homeostasis, regulation of the immune system and collective behavior of cancer cell populations. In the present study, we used a p190(BCR-ABL) driven pre-B acute lymphoblastic leukemia (ALL3) cell line derived from the pleural fluid of a terminally ill patient with ALL to test the QS hypothesis in leukemia. ALL3 cells don't grow at low density (LD) in liquid media but grow progressively faster at increasingly high cell densities (HD) in contrast to other established leukemic cell lines that grow well at very low starting cell densities. The ALL3 cells at LD are poised to grow but shortly die without additional stimulation. Supernates of ALL3 cells (HDSN) and some other primary cells grown at HD stimulate the growth of the LD ALL3 cells without which they won't survive. To get further insight into the activation processes we performed microarray analysis of the LD ALL3 cells after stimulation with ALL3 HDSN at days 1, 3, and 6. This screen identified several candidate genes, and we linked them to signaling networks and their functions. We observed that genes involved in lipid, cholesterol, fatty acid metabolism, and B cell activation are most up- or down-regulated upon stimulation of the LD ALL3 cells using HDSN. We also discuss other pathways that are differentially expressed upon stimulation of the LD ALL3 cells. Our findings suggest that the Ph+ ALL population achieves dominance by functioning as a collective aberrant ecosystem subject to defective quorum-sensing regulatory mechanisms.

Biophysical differences between chronic myelogenous leukemic quiescent and proliferating stem/progenitor cells.

The treatment of chronic myeloid leukemia (CML), a clonal myeloproliferative disorder has improved recently, but most patients have not yet been cured. Some patients develop resistance to the available tyrosine kinase treatments. Persistence of residual quiescent CML stem cells (LSCs) that later resume proliferation is another common cause of recurrence or relapse of CML. Eradication of quiescent LSCs is a promising approach to prevent recurrence of CML. Here we report on new biophysical differences between quiescent and proliferating CD34+ LSCs, and speculate how this information could be of use to eradicate quiescent LSCs. Using AFM measurements on cells collected from four untreated CML patients, substantial differences are observed between quiescent and proliferating cells in the elastic modulus, pericellular brush length and its grafting density at the single cell level. The higher pericellular brush densities of quiescent LSCs are common for all samples. The significance of these observations is discussed.

Mass spectrometry for proteomics-based investigation.

Within the past years, we have witnessed a great improvement in mass spectrometry (MS) and proteomics approaches in terms of instrumentation, protein fractionation, and bioinformatics. With the current technology, protein identification alone is no longer sufficient. Both scientists and clinicians want not only to identify proteins but also to identify the protein's posttranslational modifications (PTMs), protein isoforms, protein truncation, protein-protein interaction (PPI), and protein quantitation. Here, we describe the principle of MS and proteomics and strategies to identify proteins, protein's PTMs, protein isoforms, protein truncation, PPIs, and protein quantitation. We also discuss the strengths and weaknesses within this field. Finally, in our concluding remarks we assess the role of mass spectrometry and proteomics in scientific and clinical settings in the near future. This chapter provides an introduction and overview for subsequent chapters that will discuss specific MS proteomic methodologies and their application to specific medical conditions. Other chapters will also touch upon areas that expand beyond proteomics, such as lipidomics and metabolomics.

Cancer secretomes and their place in supplementing other hallmarks of cancer.

The secretome includes all macromolecules secreted by cells, in particular conditions at defined times, allowing cell-cell communication. Cancer cell secretomes that are altered compared to normal cells have shown significant potential for elucidating cancer biology. Proteins of secretomes are secreted by various secretory pathways and can be studied using different methods. Cancer secretomes seem to play an important role in known hallmarks of cancers such as excessive proliferation, reduced apoptosis, immune invasion, angioneogenesis, alteration in energy metabolism, and development of resistance against anti-cancer therapy [1, 2]. If a significant role of an altered secretome can be identified in cancer cells, using advanced mass spectrometry-based techniques, this may allow researchers to screen and characterize the secretome proteins involved in cancer progression and open up new opportunities to develop new therapies. We aim to elaborate upon recent advances in cancer cell secretome analysis using different proteomics techniques. In this review, we highlight the role of the altered secretome in contributing to already recognized and emerging hallmarks of cancer and we discuss new challenges in the field of secretome analysis.