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1.
Climacteric ; 25(6): 543-551, 2022 12.
Article in English | MEDLINE | ID: mdl-35771198

ABSTRACT

Technological advances have been impacting health care worldwide. Our study aimed to research the literature systematically to determine the impact of technological treatments versus conventional treatments on the quality of life of climacteric women. The study was registered on PROSPERO (CRD42021241638). We searched seven databases, including PRISMA, using mesh terms. After screening for eligibility, we selected five clinical trials, and applying the snowball technique we were able to include four more articles, totaling nine articles that used technology-based interventions (virtual reality games) during the climacteric. The total study population consisted of 298 climacteric women. Two studies evaluated a technology-based treatment for pelvic floor, one for urinary incontinence symptoms, three for postural balance, one for cardiorespiratory capacity, one for osteoporosis and one study for lower back pain. The studies showed that the technological treatments improved pelvic floor strength, balance, cardiorespiratory fitness and bone mineral density when compared to conventional treatments. Improvement was linked to adherence to training and a high level of satisfaction during the training sessions. Technology-based treatments appear to be a viable alternative to conventional treatments in improving the quality of health, with benefits for the cardiovascular, genitourinary and skeletal systems, and ultimately for the overall quality of life.


Subject(s)
Climacteric , Urinary Incontinence , Virtual Reality , Humans , Female , Quality of Life , Pelvic Floor , Exercise Therapy/methods
2.
Proc Natl Acad Sci U S A ; 111(39): 14147-52, 2014 Sep 30.
Article in English | MEDLINE | ID: mdl-25122679

ABSTRACT

Autophagy is the principal catabolic prosurvival pathway during nutritional starvation. However, excessive autophagy could be cytotoxic, contributing to cell death, but its mechanism remains elusive. Arginine starvation has emerged as a potential therapy for several types of cancers, owing to their tumor-selective deficiency of the arginine metabolism. We demonstrated here that arginine depletion by arginine deiminase induces a cytotoxic autophagy in argininosuccinate synthetase (ASS1)-deficient prostate cancer cells. Advanced microscopic analyses of arginine-deprived dying cells revealed a novel phenotype with giant autophagosome formation, nucleus membrane rupture, and histone-associated DNA leakage encaptured by autophagosomes, which we shall refer to as chromatin autophagy, or chromatophagy. In addition, nuclear inner membrane (lamin A/C) underwent localized rearrangement and outer membrane (NUP98) partially fused with autophagosome membrane. Further analysis showed that prolonged arginine depletion impaired mitochondrial oxidative phosphorylation function and depolarized mitochondrial membrane potential. Thus, reactive oxygen species (ROS) production significantly increased in both cytosolic and mitochondrial fractions, presumably leading to DNA damage accumulation. Addition of ROS scavenger N-acetyl cysteine or knockdown of ATG5 or BECLIN1 attenuated the chromatophagy phenotype. Our data uncover an atypical autophagy-related death pathway and suggest that mitochondrial damage is central to linking arginine starvation and chromatophagy in two distinct cellular compartments.


Subject(s)
Arginine/metabolism , Cell Death/physiology , DNA, Neoplasm/metabolism , Prostatic Neoplasms/metabolism , Prostatic Neoplasms/pathology , Antineoplastic Agents/pharmacology , Arginine/deficiency , Argininosuccinate Synthase/metabolism , Autophagy/drug effects , Autophagy/physiology , Cell Death/drug effects , Cell Line, Tumor , Chromatin/drug effects , Chromatin/metabolism , Humans , Hydrolases/pharmacology , Male , Membrane Potential, Mitochondrial , Microscopy, Electron, Transmission , Mitochondria/drug effects , Mitochondria/metabolism , Nuclear Envelope/drug effects , Nuclear Envelope/ultrastructure , Polyethylene Glycols/pharmacology , Prostatic Neoplasms/drug therapy , Reactive Oxygen Species/metabolism
3.
Cancer Res ; 74(24): 7498-509, 2014 Dec 15.
Article in English | MEDLINE | ID: mdl-25377473

ABSTRACT

The MAPK phosphatase MKP1 (DUSP1) is overexpressed in many human cancers, including chemoresistant and radioresistant breast cancer cells, but its functional contributions in these settings are unclear. Here, we report that after cell irradiation, MKP1 translocates into mitochondria, where it prevents apoptotic induction by limiting accumulation of phosphorylated active forms of the stress kinase JNK. Increased levels of mitochondrial MKP1 after irradiation occurred in the mitochondrial inner membrane space. Notably, cell survival regulated by mitochondrial MKP1 was responsible for conferring radioresistance in HER2-overexpressing breast cancer cells, due to the fact that MKP1 serves as a major downstream effector in the HER2-activated RAF-MEK-ERK pathway. Clinically, we documented MKP1 expression exclusively in HER2-positive breast tumors, relative to normal adjacent tissue from the same patients. MKP1 overexpression was also detected in irradiated HER2-positive breast cancer stem-like cells (HER2(+)/CD44(+)/CD24(-/low)) isolated from a radioresistant breast cancer cell population after long-term radiation treatment. MKP1 silencing reduced clonogenic survival and enhanced radiosensitivity in these stem-like cells. Combined inhibition of MKP1 and HER2 enhanced cell killing in breast cancer. Together, our findings identify a new mechanism of resistance in breast tumors and reveal MKP1 as a novel therapeutic target for radiosensitization.


Subject(s)
Breast Neoplasms/genetics , Drug Resistance, Neoplasm/genetics , Dual Specificity Phosphatase 1/biosynthesis , Radiation Tolerance/genetics , Receptor, ErbB-2/genetics , Apoptosis/drug effects , Breast Neoplasms/drug therapy , Breast Neoplasms/pathology , Dual Specificity Phosphatase 1/genetics , Female , Gene Expression Regulation, Neoplastic , HCT116 Cells , Humans , MAP Kinase Kinase 4/metabolism , MCF-7 Cells , Membrane Potential, Mitochondrial/radiation effects , Mitochondria/genetics , Mitochondria/radiation effects , Protein Transport/radiation effects
4.
J Vis Exp ; (75): e50047, 2013 May 03.
Article in English | MEDLINE | ID: mdl-23665532

ABSTRACT

Prostate cancer is the leading form of malignancies among men in the U.S. While surgery carries a significant risk of impotence and incontinence, traditional chemotherapeutic approaches have been largely unsuccessful. Hormone therapy is effective at early stage, but often fails with the eventual development of hormone-refractory tumors. We have been interested in developing therapeutics targeting specific metabolic deficiency of tumor cells. We recently showed that prostate tumor cells specifically lack an enzyme (argininosuccinate synthase, or ASS) involved in the synthesis of the amino acid arginine(1). This condition causes the tumor cells to become dependent on exogenous arginine, and they undergo metabolic stress when free arginine is depleted by arginine deiminase (ADI)(1,10). Indeed, we have shown that human prostate cancer cells CWR22Rv1 are effectively killed by ADI with caspase-independent apoptosis and aggressive autophagy (or macroautophagy)(1,2,3). Autophagy is an evolutionarily-conserved process that allows cells to metabolize unwanted proteins by lysosomal breakdown during nutritional starvation(4,5). Although the essential components of this pathway are well-characterized(6,7,8,9), many aspects of the molecular mechanism are still unclear - in particular, what is the role of autophagy in the death-response of prostate cancer cells after ADI treatment? In order to address this question, we required an experimental method to measure the level and extent of autophagic response in cells - and since there are no known molecular markers that can accurately track this process, we chose to develop an imaging-based approach, using quantitative 3D fluorescence microscopy(11,12). Using CWR22Rv1 cells specifically-labeled with fluorescent probes for autophagosomes and lysosomes, we show that 3D image stacks acquired with either widefield deconvolution microscopy (and later, with super-resolution, structured-illumination microscopy) can clearly capture the early stages of autophagy induction. With commercially available digital image analysis applications, we can readily obtain statistical information about autophagosome and lysosome number, size, distribution, and degree of colocalization from any imaged cell. This information allows us to precisely track the progress of autophagy in living cells and enables our continued investigation into the role of autophagy in cancer chemotherapy.


Subject(s)
Autophagy/physiology , Microscopy, Fluorescence/methods , Cell Line, Tumor , Fluorescent Dyes/chemistry , Humans , Imaging, Three-Dimensional/methods , Lysosomes/physiology , Male , Prostatic Neoplasms/chemistry , Prostatic Neoplasms/pathology
5.
J Med Syst ; 36(3): 1345-57, 2012 Jun.
Article in English | MEDLINE | ID: mdl-20857325

ABSTRACT

Patient records, including doctors' diagnoses of diseases, trace of treatments and patients' conditions, nursing actions, and examination results from allied health profession departments, are the most important medical records of patients in medical systems. With patient records, medical staff can instantly understand the entire medical information of a patient so that, according to the patient's conditions, more accurate diagnoses and more appropriate in-depth treatments can be provided. Nevertheless, in such a modern society with booming information technologies, traditional paper-based patient records have faced a lot of problems, such as lack of uniform formats, low data mobility, slow data transfer, illegible handwritings, enormous and insufficient storage space, difficulty of conservation, being easily damaged, and low transferability. To improve such drawbacks, reduce medical costs, and advance medical quality, paper-based patient records are modified into electronic medical records and reformed into electronic patient records. However, since electronic patient records used in various hospitals are diverse and different, in consideration of cost, it is rather difficult to establish a compatible and complete integrated electronic patient records system to unify patient records from heterogeneous systems in hospitals. Moreover, as the booming of the Internet, it is no longer necessary to build an integrated system. Instead, doctors can instantly look up patients' complete information through the Internet access to electronic patient records as well as avoid the above difficulties. Nonetheless, the major problem of accessing to electronic patient records cross-hospital systems exists in the security of transmitting and accessing to the records in case of unauthorized medical personnels intercepting or stealing the information. This study applies the Mobile Agent scheme to cope with the problem. Since a Mobile Agent is a program, which can move among hosts and automatically disperse arithmetic processes, and moves from one host to another in heterogeneous network systems with the characteristics of autonomy and mobility, decreasing network traffic, reducing transfer lag, encapsulating protocol, availability on heterogeneous platforms, fault-tolerance, high flexibility, and personalization. However, since a Mobile Agent contacts and exchanges information with other hosts or agents on the Internet for rapid exchange and access to medical information, the security is threatened. In order to solve the problem, this study proposes a key management scheme based on Lagrange interpolation formulas and hierarchical management structure to make Mobile Agents a more secure and efficient access control scheme for electronic patient record systems when applied to the access of patients' personal electronic patient records cross hospitals. Meanwhile, with the comparison of security and efficacy analyses being the feasibility of validation scheme and the basis of better efficiency, the security of Mobile Agents in the process of operation can be guaranteed, key management efficacy can be advanced, and the security of the Mobile Agent system can be protected.


Subject(s)
Access to Information , Computer Communication Networks/organization & administration , Computer Security , Electronic Health Records/organization & administration , Algorithms , Internet
6.
J Med Syst ; 36(4): 2493-503, 2012 Aug.
Article in English | MEDLINE | ID: mdl-21526332

ABSTRACT

Changes in global population and demography, and advances in medicine have led to elderly population growth, creating aging societies from which elderly medical care has evolved. In addition, with the elderly susceptible to chronic diseases, this together with the changing lifestyles of young adults have not only pushed up patient numbers of chronic diseases, but also effected into younger patients. These problems have become the major focus for the health care industry. In response to patient demand and the huge shortage of medical resources, we propose remote healthcare medical information systems that combine patient physiological data acquisition equipment with real-time health care analyses. Since remote health care systems are structured around the Internet, in addition to considering the numerous public systems spread across insecure heterogeneous networks, compatibility among heterogeneous networks will also be another concern. To address the aforementioned issues, mobile agents are adopted. With a mobile agent's characteristics of easy adaptability to heterogeneity and autonomy, the problem of heterogeneous network environments can be tackled. To construct a hierarchical safe access control mechanism for monitoring and control of patient data in order to provide the most appropriate medical treatment, we also propose to use the Chinese Remainder Theorem and discrete logarithm to classify different levels of monitoring staff and hence, to grant permission and access according to their authorized levels. We expect the methods proposed can improve medical care quality and reduce medical resource wastage, while ensuring patient privacy. Finally, security analysis of the system is conducted by simulating a variety of typical attacks, from which it can be concluded that the constructed remote healthcare information system be secure.


Subject(s)
Computer Security , Internet , Medical Records Systems, Computerized , Telecommunications , Algorithms , Confidentiality , Humans
8.
J Med Syst ; 35(4): 735-42, 2011 Aug.
Article in English | MEDLINE | ID: mdl-20703516

ABSTRACT

Electronic medical records can be defined as a digital format of the traditionally paper-based anamneses, which contains the history of a patient such as his somewhat illness, current health problems, and his chronic treatments. An electronic anamnesis is meant to make the patient's health information more conveniently accessible and transferable between different medical institutions and also easier to be kept quite a long time. Because of such transferability and accessibility of electronic anamneses, we can use less resource than before on storing the patients' medical information. This also means that medical care providers could save more funds on record-keeping and access a patient's medical background directly since shown on the computer screen more quickly and easily. Overall, the service quality has seemingly improved greatly. However, the usage of electronic anamneses involves in some concerned issues such as its related law declaration, and the security of the patient's confidential information. Because of these concerns, a secure medical networking scheme is taking into consideration. Nowadays, the administrators at the medical institutions are facing more challenges on monitoring computers and network systems, because of dramatic advances in this field. For instance, a trusted third party is authorized to access some medical records for a certain period of time. In regard to the security purpose, all the electronic medical records are embedded with both of the public-key infrastructure (PKI) cryptography and the digital signature technique so as to ensure the records well-protected. Since the signatures will be invalid due to the revocation or time expiration, the security of records under this premise would turn into vulnerable. Hence, we propose a re-signing scheme, whose purpose is to make a going-expired digital signature been resigned in time, in keeping with the premise of not conflicting with the laws, morals, and privacy while maintaining the security of the electronic medical records.


Subject(s)
Computer Security , Confidentiality , Medical Records Systems, Computerized/organization & administration , Humans
9.
Cell Host Microbe ; 10(6): 551-62, 2011 Dec 15.
Article in English | MEDLINE | ID: mdl-22177560

ABSTRACT

HIV-1 can infect T cells by cell-free virus or by direct virion transfer between cells through cell contact-induced structures called virological synapses (VS). During VS-mediated infection, virions accumulate within target cell endosomes. We show that after crossing the VS, the transferred virus undergoes both maturation and viral membrane fusion. Following VS transfer, viral membrane fusion occurs with delayed kinetics and transferred virions display reduced sensitivity to patient antisera compared to mature, cell-free virus. Furthermore, particle fusion requires that the transferred virions undergo proteolytic maturation within acceptor cell endosomes, which occurs over several hours. Rapid, live cell confocal microscopy demonstrated that viral fusion can occur in compartments that have moved away from the VS. Thus, HIV particle maturation activates viral fusion in target CD4+ T cell endosomes following transfer across the VS and may represent a pathway by which HIV evades antibody neutralization.


Subject(s)
Endosomes/virology , HIV Infections/virology , HIV-1/physiology , Synapses/virology , Virion/physiology , CD4-Positive T-Lymphocytes/virology , Cell Line , Humans , Virus Internalization
10.
Cancer Res ; 69(2): 700-8, 2009 Jan 15.
Article in English | MEDLINE | ID: mdl-19147587

ABSTRACT

Arginine deprivation as an anticancer therapy has historically been met with limited success. The development of pegylated arginine deiminase (ADI-PEG20) has renewed interest in arginine deprivation for the treatment of some cancers. The efficacy of ADI-PEG20 is directly correlated with argininosuccinate synthetase (ASS) deficiency. CWR22Rv1 prostate cancer cells do not express ASS, the rate-limiting enzyme in arginine synthesis, and are susceptible to ADI-PEG20 in vitro. Interestingly, apoptosis by 0.3 microg/mL ADI-PEG20 occurs 96 hours posttreatment and is caspase independent. The effect of ADI-PEG20 in vivo reveals reduced tumor activity by micropositron emission tomography as well as reduced tumor growth as a monotherapy and in combination with docetaxel against CWR22Rv1 mouse xenografts. In addition, we show autophagy is induced by single amino acid depletion by ADI-PEG20. Here, autophagy is an early event that is detected within 1 to 4 hours of 0.3 microg/mL ADI-PEG20 treatment and is an initial protective response to ADI-PEG20 in CWR22Rv1 cells. Significantly, the inhibition of autophagy by chloroquine and Beclin1 siRNA knockdown enhances and accelerates ADI-PEG20-induced cell death. PC3 cells, which express reduced ASS, also undergo autophagy and are responsive to autophagy inhibition and ADI-PEG20 treatment. In contrast, LNCaP cells highly express ASS and are therefore resistant to both ADI-PEG20 and autophagic inhibition. These data point to an interrelationship among ASS deficiency, autophagy, and cell death by ADI-PEG20. Finally, a tissue microarray of 88 prostate tumor samples lacked expression of ASS, indicating ADI-PEG20 is a potential novel therapy for the treatment of prostate cancer


Subject(s)
Apoptosis/drug effects , Autophagy/drug effects , Hydrolases/administration & dosage , Hydrolases/pharmacology , Polyethylene Glycols/pharmacology , Prostatic Neoplasms/drug therapy , Animals , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Argininosuccinate Synthase/biosynthesis , Argininosuccinate Synthase/deficiency , Caspase 3/metabolism , Cell Line, Tumor , Docetaxel , Drug Synergism , Humans , Male , Mice , Mice, Inbred BALB C , Mice, Nude , Polyethylene Glycols/administration & dosage , Prostatic Neoplasms/enzymology , Prostatic Neoplasms/metabolism , Prostatic Neoplasms/pathology , Taxoids/administration & dosage , Taxoids/pharmacology , Xenograft Model Antitumor Assays
11.
Science ; 323(5922): 1743-7, 2009 Mar 27.
Article in English | MEDLINE | ID: mdl-19325119

ABSTRACT

The spread of HIV between immune cells is greatly enhanced by cell-cell adhesions called virological synapses, although the underlying mechanisms have been unclear. With use of an infectious, fluorescent clone of HIV, we tracked the movement of Gag in live CD4 T cells and captured the direct translocation of HIV across the virological synapse. Quantitative, high-speed three-dimensional (3D) video microscopy revealed the rapid formation of micrometer-sized "buttons" containing oligomerized viral Gag protein. Electron microscopy showed that these buttons were packed with budding viral crescents. Viral transfer events were observed to form virus-laden internal compartments within target cells. Continuous time-lapse monitoring showed preferential infection through synapses. Thus, HIV dissemination may be enhanced by virological synapse-mediated cell adhesion coupled to viral endocytosis.


Subject(s)
CD4-Positive T-Lymphocytes/physiology , CD4-Positive T-Lymphocytes/virology , Cell Adhesion , HIV/physiology , Virus Internalization , gag Gene Products, Human Immunodeficiency Virus/metabolism , CD4-Positive T-Lymphocytes/ultrastructure , Coculture Techniques , Cytochalasin D/pharmacology , Endocytosis , HIV/ultrastructure , Humans , Imaging, Three-Dimensional , Jurkat Cells , Microscopy, Confocal , Microscopy, Electron, Transmission , Microscopy, Video , Receptors, CCR5/metabolism , Receptors, CXCR4/metabolism , Recombinant Fusion Proteins/metabolism
12.
Electrophoresis ; 29(5): 1131-9, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18246574

ABSTRACT

Metallic nanoparticles suspended in aqueous solutions and functionalized with chemical and biological surface coatings are important elements in basic and applied nanoscience research. Many applications require an understanding of the electrokinetic or colloidal properties of such particles. We describe the results of experiments to measure the zeta potential of metallic nanorod particles in aqueous saline solutions, including the effects of pH, ionic strength, metallic composition, and surface functionalization state. Particle substrates tested include gold, silver, and palladium monometallic particles as well as gold/silver bimetallic particles. Surface functionalization conditions included 11-mercaptoundecanoic acid (MUA), mercaptoethanol (ME), and mercaptoethanesulfonic acid (MESA) self-assembled monolayers (SAMs), as well as MUA layers subsequently derivatized with proteins. For comparison, we present zeta potential data for typical charge-stabilized polystyrene particles. We compare experimental zeta potential data with theoretically predicted values for SAM-coated and bimetallic particles. The results of these studies are useful in predicting and controlling the aggregation, adhesion, and transport of functionalized metallic nanoparticles within microfluidic devices and other systems.


Subject(s)
Electrophoresis/methods , Metal Nanoparticles/chemistry , Electricity , Fatty Acids/chemistry , Gold/chemistry , Models, Theoretical , Sulfhydryl Compounds/chemistry
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