Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 96
Filter
Add more filters

Country/Region as subject
Publication year range
1.
MMWR Morb Mortal Wkly Rep ; 72(6): 145-152, 2023 02 10.
Article in English | MEDLINE | ID: mdl-36757865

ABSTRACT

On September 1, 2022, CDC recommended an updated (bivalent) COVID-19 vaccine booster to help restore waning protection conferred by previous vaccination and broaden protection against emerging variants for persons aged ≥12 years (subsequently extended to persons aged ≥6 months).* To assess the impact of original (monovalent) COVID-19 vaccines and bivalent boosters, case and mortality rate ratios (RRs) were estimated comparing unvaccinated and vaccinated persons aged ≥12 years by overall receipt of and by time since booster vaccination (monovalent or bivalent) during Delta variant and Omicron sublineage (BA.1, BA.2, early BA.4/BA.5, and late BA.4/BA.5) predominance.† During the late BA.4/BA.5 period, unvaccinated persons had higher COVID-19 mortality and infection rates than persons receiving bivalent doses (mortality RR = 14.1 and infection RR = 2.8) and to a lesser extent persons vaccinated with only monovalent doses (mortality RR = 5.4 and infection RR = 2.5). Among older adults, mortality rates among unvaccinated persons were significantly higher than among those who had received a bivalent booster (65-79 years; RR = 23.7 and ≥80 years; 10.3) or a monovalent booster (65-79 years; 8.3 and ≥80 years; 4.2). In a second analysis stratified by time since booster vaccination, there was a progressive decline from the Delta period (RR = 50.7) to the early BA.4/BA.5 period (7.4) in relative COVID-19 mortality rates among unvaccinated persons compared with persons receiving who had received a monovalent booster within 2 weeks-2 months. During the early BA.4/BA.5 period, declines in relative mortality rates were observed at 6-8 (RR = 4.6), 9-11 (4.5), and ≥12 (2.5) months after receiving a monovalent booster. In contrast, bivalent boosters received during the preceding 2 weeks-2 months improved protection against death (RR = 15.2) during the late BA.4/BA.5 period. In both analyses, when compared with unvaccinated persons, persons who had received bivalent boosters were provided additional protection against death over monovalent doses or monovalent boosters. Restored protection was highest in older adults. All persons should stay up to date with COVID-19 vaccination, including receipt of a bivalent booster by eligible persons, to reduce the risk for severe COVID-19.


Subject(s)
COVID-19 Vaccines , COVID-19 , Humans , Aged , COVID-19/epidemiology , COVID-19/prevention & control , Incidence , SARS-CoV-2 , Vaccination
2.
MMWR Morb Mortal Wkly Rep ; 72(15): 404-410, 2023 Apr 14.
Article in English | MEDLINE | ID: mdl-37053126

ABSTRACT

As of March 7, 2023, a total of 30,235 confirmed and probable monkeypox (mpox) cases were reported in the United States,† predominantly among cisgender men§ who reported recent sexual contact with another man (1). Although most mpox cases during the current outbreak have been self-limited, cases of severe illness and death have been reported (2-4). During May 10, 2022-March 7, 2023, 38 deaths among persons with probable or confirmed mpox¶ (1.3 per 1,000 mpox cases) were reported to CDC and classified as mpox-associated (i.e., mpox was listed as a contributing or causal factor). Among the 38 mpox-associated deaths, 94.7% occurred in cisgender men (median age = 34 years); 86.8% occurred in non-Hispanic Black or African American (Black) persons. The median interval from symptom onset to death was 68 days (IQR = 50-86 days). Among 33 decedents with available information, 93.9% were immunocompromised because of HIV. Public health actions to prevent mpox deaths include integrated testing, diagnosis, and early treatment for mpox and HIV, and ensuring equitable access to both mpox and HIV prevention and treatment, such as antiretroviral therapy (ART) (5).


Subject(s)
Mpox (monkeypox) , Adult , Humans , Male , Black or African American , Disease Outbreaks , Mpox (monkeypox)/mortality , Public Health , United States/epidemiology
3.
MMWR Morb Mortal Wkly Rep ; 70(1): 20-23, 2021 Jan 08.
Article in English | MEDLINE | ID: mdl-33411698

ABSTRACT

Preventing transmission of SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19), in colleges and universities requires mitigation strategies that address on- and off-campus congregate living settings as well as extracurricular activities and other social gatherings (1-4). At the start of the academic year, sorority and fraternity organizations host a series of recruitment activities known as rush week; rush week culminates with bid day, when selections are announced. At university A in Arkansas, sorority rush week (for women) was held during August 17-22, 2020, and consisted of on- and off-campus social gatherings, including an outdoor bid day event on August 22. Fraternity rush week (for men) occurred during August 27-31, with bid day scheduled for September 5. During August 22-September 5, university A-associated COVID-19 cases were reported to the Arkansas Department of Health (ADH). A total of 965 confirmed and probable COVID-19 cases associated with university A were identified, with symptom onset occurring during August 20-September 5, 2020; 31% of the patients with these cases reported involvement in any fraternity or sorority activity. Network analysis identified 54 gatherings among all linkages of cases to places of residence and cases to events, 49 (91%) were linked by participation in fraternity and sorority activities accounting for 42 (72%) links among gatherings. On September 4, university A banned gatherings of ≥10 persons, and fraternity bid day was held virtually. The rapid increase in COVID-19 cases was likely facilitated by on- and off-campus congregate living settings and activities, and health departments should work together with student organizations and university leadership to ensure compliance with mitigation measures.


Subject(s)
COVID-19/epidemiology , COVID-19/transmission , College Fraternities and Sororities/organization & administration , Community-Acquired Infections/epidemiology , Adolescent , Adult , Aged , Arkansas/epidemiology , COVID-19/prevention & control , Child , Child, Preschool , Community-Acquired Infections/prevention & control , Female , Humans , Infant , Infant, Newborn , Male , Middle Aged , Universities , Young Adult
4.
Prev Med ; 153: 106818, 2021 12.
Article in English | MEDLINE | ID: mdl-34599924

ABSTRACT

The coronavirus disease 2019 (COVID-19) pandemic has been associated with a declining volume of patients seen in the emergency department. Despite the need for seeking urgent care for conditions such as myocardial infarction, many people may not seek treatment. This study seeks to measure associations between the COVID-19 pandemic and location of death among individuals who died from ischemic heart disease (IHD). Data obtained from death certificates from the Arkansas Department of Health was used to conduct a difference-in-difference analysis to assess whether decedents of IHD were more likely to die at home during the pandemic (March 2020 through September 2020). The analysis compared location of death for decedents of IHD pre and during the pandemic to location of death for decedents from non-natural causes. Before the pandemic, 50.0% of decedents of IHD died at home compared to 57.9% dying at home during (through September 2020) the pandemic study period (p < .001). There was no difference in the proportion of decedents who died at home from non-natural causes before and during the pandemic study period (55.8% vs. 53.5%; p = .21). After controlling for confounders, there was a 48% increase in the odds of dying at home from IHD during the pandemic study period (p < .001) relative to the change in dying at home due to non-natural causes. During the study period, there was an increase in the proportion of decedents who died at home due to IHD. Despite the ongoing pandemic, practitioners should emphasize the need to seek urgent care during an emergency.


Subject(s)
COVID-19 , Myocardial Ischemia , Emergency Service, Hospital , Humans , Myocardial Ischemia/epidemiology , Pandemics , SARS-CoV-2
5.
Proc Natl Acad Sci U S A ; 115(28): 7254-7259, 2018 07 10.
Article in English | MEDLINE | ID: mdl-29941557

ABSTRACT

Direct delivery of fluid to brain parenchyma is critical in both research and clinical settings. This is usually accomplished through acutely inserted cannulas. This technique, however, results in backflow and significant dispersion away from the infusion site, offering little spatial or temporal control in delivering fluid. We present an implantable, MRI-compatible, remotely controlled drug delivery system for minimally invasive interfacing with brain microstructures in freely moving animals. We show that infusions through acutely inserted needles target a region more than twofold larger than that of identical infusions through chronically implanted probes due to reflux and backflow. We characterize the dynamics of in vivo infusions using positron emission tomography techniques. Volumes as small as 167 nL of copper-64 and fludeoxyglucose labeled agents are quantified. We further demonstrate the importance of precise drug volume dosing to neural structures to elicit behavioral effects reliably. Selective modulation of the substantia nigra, a critical node in basal ganglia circuitry, via muscimol infusion induces behavioral changes in a volume-dependent manner, even when the total dose remains constant. Chronic device viability is confirmed up to 1-y implantation in rats. This technology could potentially enable precise investigation of neurological disease pathology in preclinical models, and more efficacious treatment in human patients.


Subject(s)
Basal Ganglia/diagnostic imaging , Copper/pharmacology , Drug Delivery Systems , Fluorodeoxyglucose F18/pharmacology , Magnetic Resonance Imaging/methods , Substantia Nigra/diagnostic imaging , Animals , Drug Delivery Systems/instrumentation , Drug Delivery Systems/methods , Rats
6.
Clin Infect Dis ; 71(7): e178-e185, 2020 10 23.
Article in English | MEDLINE | ID: mdl-31872853

ABSTRACT

BACKGROUND: In July 2018, the Arkansas Department of Health (ADH) was notified by hospital A of 3 patients with bloodstream infections (BSIs) with a rapidly growing nontuberculous Mycobacterium (NTM) species; on 5 September 2018, 6 additional BSIs were reported. All were among oncology patients at clinic A. We investigated to identify sources and to prevent further infections. METHODS: ADH performed an onsite investigation at clinic A on 7 September 2018 and reviewed patient charts, obtained environmental samples, and cultured isolates. The isolates were sequenced (whole genome, 16S, rpoB) by the Centers for Disease Control and Prevention to determine species identity and relatedness. RESULTS: By 31 December 2018, 52 of 151 (34%) oncology patients with chemotherapy ports accessed at clinic A during 22 March-12 September 2018 had NTM BSIs. Infected patients received significantly more saline flushes than uninfected patients (P < .001) during the risk period. NTM grew from 6 unused saline flushes compounded by clinic A. The identified species was novel and designated Mycobacterium FVL 201832. Isolates from patients and saline flushes were highly related by whole-genome sequencing, indicating a common source. Clinic A changed to prefilled saline flushes on 12 September as recommended. CONCLUSIONS: Mycobacterium FVL 201832 caused BSIs in oncology clinic patients. Laboratory data allowed investigators to rapidly link infections to contaminated saline flushes; cooperation between multiple institutions resulted in timely outbreak resolution. New state policies being considered because of this outbreak include adding extrapulmonary NTM to ADH's reportable disease list and providing more oversight to outpatient oncology clinics.


Subject(s)
Mycobacterium Infections, Nontuberculous , Neoplasms , Sepsis , Arkansas , Humans , Mycobacterium Infections, Nontuberculous/epidemiology , Neoplasms/complications , Nontuberculous Mycobacteria , Outpatients
7.
Magn Reson Med ; 83(4): 1390-1404, 2020 04.
Article in English | MEDLINE | ID: mdl-31631380

ABSTRACT

PURPOSE: Undiagnosed dehydration compromises health outcomes across many populations. Existing dehydration diagnostics require invasive bodily fluid sampling or are easily confounded by fluid and electrolyte intake, environment, and physical activity limiting widespread adoption. We present a portable MR sensor designed to measure intramuscular fluid shifts to identify volume depletion. METHODS: Fluid loss is induced via a mouse model of thermal dehydration (37°C; 15-20% relative humidity). We demonstrate quantification of fluid loss induced by hyperosmotic dehydration with multicomponent T2 relaxometry using both a benchtop NMR system and MRI localized to skeletal muscle tissue. We then describe a miniaturized (~1000 cm3 ) portable (~4 kg) MR sensor (0.28 T) designed to identify dehydration-induced fluid loss. T2 relaxometry measurements were performed using a Carr-Purcell-Meiboom-Gill pulse sequence in ~4 min. RESULTS: T2 values from the portable MR sensor exhibited strong (R2 = 0.996) agreement with benchtop NMR spectrometer. Thermal dehydration induced weight loss of 4 to 11% over 5 to 10 h. Fluid loss induced by thermal dehydration was accurately identified via whole-animal NMR and skeletal muscle. The portable MR sensor accurately identified dehydration via multicomponent T2 relaxometry. CONCLUSION: Performing multicomponent T2 relaxometry localized to the skeletal muscle with a miniaturized MR sensor provides a noninvasive, physiologically relevant measure of dehydration induced fluid loss in a mouse model. This approach offers sensor portability, reduced system complexity, fully automated operation, and low cost compared with MRI. This approach may serve as a versatile and portable point of care technique for dehydration monitoring.


Subject(s)
Dehydration , Magnetic Resonance Imaging , Animals , Dehydration/diagnostic imaging , Magnetic Resonance Spectroscopy , Mice , Muscle, Skeletal/diagnostic imaging
8.
Proc Natl Acad Sci U S A ; 114(50): 13260-13265, 2017 12 12.
Article in English | MEDLINE | ID: mdl-29158415

ABSTRACT

Many debilitating neuropsychiatric and neurodegenerative disorders are characterized by dopamine neurotransmitter dysregulation. Monitoring subsecond dopamine release accurately and for extended, clinically relevant timescales is a critical unmet need. Especially valuable has been the development of electrochemical fast-scan cyclic voltammetry implementing microsized carbon fiber probe implants to record fast millisecond changes in dopamine concentrations. Nevertheless, these well-established methods have only been applied in primates with acutely (few hours) implanted sensors. Neurochemical monitoring for long timescales is necessary to improve diagnostic and therapeutic procedures for a wide range of neurological disorders. Strategies for the chronic use of such sensors have recently been established successfully in rodents, but new infrastructures are needed to enable these strategies in primates. Here we report an integrated neurochemical recording platform for monitoring dopamine release from sensors chronically implanted in deep brain structures of nonhuman primates for over 100 days, together with results for behavior-related and stimulation-induced dopamine release. From these chronically implanted probes, we measured dopamine release from multiple sites in the striatum as induced by behavioral performance and reward-related stimuli, by direct stimulation, and by drug administration. We further developed algorithms to automate detection of dopamine. These algorithms could be used to track the effects of drugs on endogenous dopamine neurotransmission, as well as to evaluate the long-term performance of the chronically implanted sensors. Our chronic measurements demonstrate the feasibility of measuring subsecond dopamine release from deep brain circuits of awake, behaving primates in a longitudinally reproducible manner.


Subject(s)
Brain/metabolism , Dopamine/metabolism , Electroencephalography/methods , Neurophysiological Monitoring/methods , Animals , Brain/physiology , Electrodes, Implanted , Electroencephalography/instrumentation , Female , Macaca mulatta , Neurophysiological Monitoring/instrumentation , Reward , Time Factors
9.
Small ; 15(37): e1901459, 2019 09.
Article in English | MEDLINE | ID: mdl-31183933

ABSTRACT

Enhanced understanding of neuropathologies has created a need for more advanced tools. Current neural implants result in extensive glial scarring and are not able to highly localize drug delivery due to their size. Smaller implants reduce surgical trauma and improve spatial resolution, but such a reduction requires improvements in device design to enable accurate and chronic implantation in subcortical structures. Flexible needle steering techniques offer improved control over implant placement, but often require complex closed-loop control for accurate implantation. This study reports the development of steerable microinvasive neural implants (S-MINIs) constructed from borosilicate capillaries (OD = 60 µm, ID = 20 µm) that do not require closed-loop guidance or guide tubes. S-MINIs reduce glial scarring 3.5-fold compared to prior implants. Bevel steered needles are utilized for open-loop targeting of deep-brain structures. This study demonstrates a sinusoidal relationship between implant bevel angle and the trajectory radius of curvature both in vitro and ex vivo. This relationship allows for bevel-tipped capillaries to be steered to a target with an average error of 0.23 mm ± 0.19 without closed-loop control. Polished microcapillaries present a new microinvasive tool for chronic, predictable targeting of pathophysiological structures without the need for closed-loop feedback and complex imaging.


Subject(s)
Robotic Surgical Procedures/methods , Animals , Brain/metabolism , Drug Delivery Systems/methods , Equipment Design , Female , Humans , Microscopy, Fluorescence/methods , Phantoms, Imaging , Rats , Rats, Inbred F344 , Swine
10.
Analyst ; 143(20): 4836-4839, 2018 Oct 08.
Article in English | MEDLINE | ID: mdl-30070266

ABSTRACT

We describe a label-free approach based on Raman spectroscopy, to study drug-induced apoptosis in vivo. Spectral-shifts at wavenumbers associated with DNA, proteins, lipids, and collagen have been identified on breast and melanoma tumor tissues. These findings may enable a new analytical method for rapid readout of drug-therapy with miniaturized probes.


Subject(s)
Apoptosis/drug effects , Breast Neoplasms/metabolism , Melanoma/metabolism , Spectrum Analysis, Raman/methods , Animals , Antibodies/immunology , Antineoplastic Agents/pharmacology , Caspase 3/immunology , Caspase 3/metabolism , Doxorubicin/pharmacology , Immunohistochemistry , Intercalating Agents/pharmacology , Mice, Nude
11.
J Community Health ; 43(2): 207-211, 2018 04.
Article in English | MEDLINE | ID: mdl-28707181

ABSTRACT

To describe the Medicaid costs associated with persons who are homeless or unstably housed. A retrospective secondary data analysis linked Medicaid recipient data with a statewide homeless management information system. A total of 19,950 persons received a housing service between 2012 and 2015 including 14,136 persons with Medicaid. Five of the most frequent diagnoses were substance abuse or mental health conditions in 42.83% of all diagnoses. The most frequent service was outpatient mental health and emergency department physician services. These costs totaled $166,653,689 with prescription drug costs at $62,800,463, with a total cost of $672,242,449, averaging $14,632.42 per 12-month period per person. The potential changes in Medicaid could lead to cost transfers or a reduction in services. Recognizing these are significant costs by homeless and unstably housed persons only, these high costs warrant the determination of points in care where effective cost saving interventions may be employed.


Subject(s)
Ill-Housed Persons , Medicaid , Mental Health Services/statistics & numerical data , Patient Acceptance of Health Care/statistics & numerical data , Substance-Related Disorders/therapy , Humans , Medicaid/economics , Medicaid/statistics & numerical data , United States , Vulnerable Populations
12.
Gynecol Oncol ; 146(1): 161-169, 2017 07.
Article in English | MEDLINE | ID: mdl-28499648

ABSTRACT

OBJECTIVE: Most ovarian cancer patients present with advanced-stage disease, disseminated in the peritoneal cavity. Standard treatment involves surgical resection of all visible tumor, followed by delivery of systemic therapy. Patients with advanced-stage disease may be candidates for intraperitoneal (IP) chemotherapy following surgical debulking. Recent clinical trials have created controversy regarding the benefits of this approach. Previous clinical trials report that patients with microscopic residual disease respond best to IP therapy. The goal of this study was to determine the relationship between tumor size and the efficacy of continuous chemotherapy. METHODS: Small and large ovarian cancer spheroids (derived from UCI101 and A2780 cell lines) were exposed to short-term high (modeling an IP injection, "IP") or prolonged, low cisplatin concentrations (modeling an implanted device, "device"), which have been previously shown to be less toxic. Spheroid diameter was measured at various time points via image analysis and used to quantify tumor shrinkage over the course of treatment. RESULTS: We show that "IP" doses more effectively shrink large spheroids when the same cumulative dose is administered with both treatments, but that both regimens similarly treat small spheroids. We also demonstrate that higher cumulative "device" doses are most effective at shrinking large spheroids. CONCLUSIONS: These results support the hypothesis that intratumoral drug distribution following IP treatment is diffusion-controlled. An implanted device that continuously delivers low doses of IP chemotherapy would, therefore, be maximally effective against microscopic tumors.


Subject(s)
Antineoplastic Agents/administration & dosage , Cisplatin/administration & dosage , Ovarian Neoplasms/drug therapy , Ovarian Neoplasms/pathology , Cell Line, Tumor , Drug Administration Schedule , Female , Humans , Spheroids, Cellular/drug effects , Spheroids, Cellular/pathology
13.
Proc Natl Acad Sci U S A ; 111(18): 6588-93, 2014 May 06.
Article in English | MEDLINE | ID: mdl-24753603

ABSTRACT

Targeted MRI contrast agents have proven useful in research and clinical studies for highlighting specific metabolites and biomarkers [Davies GL, et al. (2013) Chem Commun (Camb) 49(84):9704-9721] but their applicability in serial imaging is limited owing to a changing concentration postinjection. Solid enclosures have previously been used to keep the local concentration of contrast agent constant, but the need to surgically implant these devices limits their use [Daniel K, et al. (2009) Biosens Bioelectron 24(11):3252-3257]. This paper describes a novel class of contrast agent that comprises a responsive material for contrast generation and an injectable polymeric matrix for structural support. Using this principle, we have designed a contrast agent sensitive to oxygen, which is composed of dodecamethylpentasiloxane as the responsive material and polydimethylsiloxane as the matrix material. A rodent inspired-gas model demonstrated that these materials are functionally stable in vivo for at least 1 mo, which represents an order of magnitude improvement over an injection of liquid siloxane [Kodibagkar VD, et al. (2006) Magn Reson Med 55(4):743-748]. We also observed minimal adverse tissue reactions or migration of contrast agents from the initial injection site. This class of contrast agents, thus, represented a new and complementary method to monitor chronic diseases by MRI.


Subject(s)
Contrast Media/chemistry , Magnetic Resonance Imaging/methods , Oxygen/analysis , Siloxanes/chemistry , Animals , Biosensing Techniques/methods , Contrast Media/administration & dosage , Dimethylpolysiloxanes/chemistry , Humans , Microspheres , Rats , Rats, Sprague-Dawley , Siloxanes/administration & dosage
14.
Proc Natl Acad Sci U S A ; 111(45): 16071-6, 2014 Nov 11.
Article in English | MEDLINE | ID: mdl-25349381

ABSTRACT

Metastases represent the most common brain tumors in adults. Surgical resection alone results in 45% recurrence and is usually accompanied by radiation and chemotherapy. Adequate chemotherapy delivery to the CNS is hindered by the blood-brain barrier. Efforts at delivering chemotherapy locally to gliomas have shown modest increases in survival, likely limited by the infiltrative nature of the tumor. Temozolomide (TMZ) is first-line treatment for gliomas and recurrent brain metastases. Doxorubicin (DOX) is used in treating many types of breast cancer, although its use is limited by severe cardiac toxicity. Intracranially implanted DOX and TMZ microcapsules are compared with systemic administration of the same treatments in a rodent model of breast adenocarcinoma brain metastases. Outcomes were animal survival, quantified drug exposure, and distribution of cleaved caspase 3. Intracranial delivery of TMZ and systemic DOX administration prolong survival more than intracranial DOX or systemic TMZ. Intracranial TMZ generates the more robust induction of apoptotic pathways. We postulate that these differences may be explained by distribution profiles of each drug when administered intracranially: TMZ displays a broader distribution profile than DOX. These microcapsule devices provide a safe, reliable vehicle for intracranial chemotherapy delivery and have the capacity to be efficacious and superior to systemic delivery of chemotherapy. Future work should include strategies to improve the distribution profile. These findings also have broader implications in localized drug delivery to all tissue, because the efficacy of a drug will always be limited by its ability to diffuse into surrounding tissue past its delivery source.


Subject(s)
Adenocarcinoma/drug therapy , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Brain Neoplasms/drug therapy , Mammary Neoplasms, Experimental/drug therapy , Adenocarcinoma/metabolism , Adenocarcinoma/pathology , Animals , Brain Neoplasms/metabolism , Brain Neoplasms/pathology , Brain Neoplasms/secondary , Capsules , Caspase 3/metabolism , Dacarbazine/analogs & derivatives , Dacarbazine/pharmacology , Doxorubicin/pharmacology , Female , Humans , Mammary Neoplasms, Experimental/metabolism , Mammary Neoplasms, Experimental/pathology , Neoplasm Metastasis , Neoplasm Proteins/metabolism , Rats , Rats, Inbred F344 , Temozolomide
16.
NMR Biomed ; 28(8): 1031-9, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26123278

ABSTRACT

Dehydration is a prevalent pathology, where loss of bodily water can result in variable symptoms. Symptoms can range from simple thirst to dire scenarios involving loss of consciousness. Clinical methods exist that assess dehydration from qualitative weight changes to more quantitative osmolality measurements. These methods are imprecise, invasive, and/or easily confounded, despite being practiced clinically. We investigate a non-invasive, non-imaging (1)H NMR method of assessing dehydration that attempts to address issues with existing clinical methods. Dehydration was achieved by exposing mice (n = 16) to a thermally elevated environment (37 °C) for up to 7.5 h (0.11-13% weight loss). Whole body NMR measurements were made using a Bruker LF50 BCA-Analyzer before and after dehydration. Physical lean tissue, adipose, and free water compartment approximations had NMR values extracted from relaxation data through a multi-exponential fitting method. Changes in before/after NMR values were compared with clinically practiced metrics of weight loss (percent dehydration) as well as blood and urine osmolality. A linear correlation between tissue relaxometry and both animal percent dehydration and urine osmolality was observed in lean tissue, but not adipose or free fluids. Calculated R(2) values for percent dehydration were 0.8619 (lean, P < 0.0001), 0.5609 (adipose, P = 0.0008), and 0.0644 (free fluids, P = 0.3445). R(2) values for urine osmolality were 0.7760 (lean, P < 0.0001), 0.5005 (adipose, P = 0.0022), and 0.0568 (free fluids, P = 0.3739). These results suggest that non-imaging (1)H NMR methods are capable of non-invasively assessing dehydration in live animals.


Subject(s)
Body Water/metabolism , Dehydration/diagnosis , Dehydration/metabolism , Diagnosis, Computer-Assisted/methods , Proton Magnetic Resonance Spectroscopy/methods , Algorithms , Animals , Biomarkers/metabolism , Female , Mice , Reproducibility of Results , Sensitivity and Specificity
17.
Mol Ther ; 22(5): 999-1007, 2014 May.
Article in English | MEDLINE | ID: mdl-24496384

ABSTRACT

The secreted proteins from a cell constitute a natural biologic library that can offer significant insight into human health and disease. Discovering new secreted proteins from cells is bounded by the limitations of traditional separation and detection tools to physically fractionate and analyze samples. Here, we present a new method to systematically identify bioactive cell-secreted proteins that circumvent traditional proteomic methods by first enriching for protein candidates by differential gene expression profiling. The bone marrow stromal cell secretome was analyzed using enriched gene expression datasets in combination with potency assay testing. Four proteins expressed by stromal cells with previously unknown anti-inflammatory properties were identified, two of which provided a significant survival benefit to mice challenged with lethal endotoxic shock. Greater than 85% of secreted factors were recaptured that were otherwise undetected by proteomic methods, and remarkable hit rates of 18% in vitro and 9% in vivo were achieved.


Subject(s)
Contractile Proteins/genetics , Contractile Proteins/metabolism , Enkephalins/genetics , Extracellular Matrix Proteins/metabolism , Glycoproteins/genetics , Interleukin-10/metabolism , Protein Precursors/genetics , Proteins/metabolism , Shock, Septic/therapy , Animals , Bone Marrow Cells/immunology , Bone Marrow Cells/metabolism , Enkephalins/metabolism , Extracellular Matrix Proteins/genetics , Gene Expression Profiling , Humans , Intercellular Signaling Peptides and Proteins , Interleukin-10/genetics , Mesenchymal Stem Cells/immunology , Mesenchymal Stem Cells/metabolism , Mice , Protein Biosynthesis/genetics , Protein Precursors/metabolism , Proteins/genetics , Proteomics , RNA Splicing Factors , Shock, Septic/genetics
18.
Nat Commun ; 15(1): 440, 2024 Jan 10.
Article in English | MEDLINE | ID: mdl-38199994

ABSTRACT

Magnetic resonance imaging is a widespread clinical tool for the detection of soft tissue morphology and pathology. However, the clinical deployment of magnetic resonance imaging scanners is ultimately limited by size, cost, and space constraints. Here, we discuss the design and performance of a low-field single-sided magnetic resonance sensor intended for point-of-care evaluation of skeletal muscle in vivo. The 11 kg sensor has a penetration depth of >8 mm, which allows for an accurate analysis of muscle tissue and can avoid signal from more proximal layers, including subcutaneous adipose tissue. Low operational power and shielding requirements are achieved through the design of a permanent magnet array and surface transceiver coil. The sensor can acquire high signal-to-noise measurements in minutes, making it practical as a point-of-care tool for many quantitative diagnostic measurements, including T2 relaxometry. In this work, we present the in vitro and human in vivo performance of the device for muscle tissue evaluation.


Subject(s)
Magnetic Resonance Imaging , Point-of-Care Systems , Humans , Muscle, Skeletal/diagnostic imaging , Subcutaneous Fat , Magnetic Resonance Spectroscopy
19.
Res Sq ; 2023 Sep 19.
Article in English | MEDLINE | ID: mdl-37790511

ABSTRACT

Magnetic resonance (MR) imaging is a powerful clinical tool for the detection of soft tissue morphology and pathology, which often provides actionable diagnostic information to clinicians. Its clinical use is largely limited due to size, cost, time, and space constraints. Here, we discuss the design and performance of a low-field single-sided MR sensor intended for point-of-care (POC) evaluation of skeletal muscle in vivo. The 11kg sensor has a penetration depth of > 8 mm, which allows for an accurate analysis of muscle tissue and can avoid signal from more proximal layers, including subcutaneous adipose tissue. Low operational power and minimal shielding requirements are achieved through the design of a permanent magnet array and surface transceiver coil. We present the in vitro and human in vivo performance of the device for muscle tissue evaluation. The sensor can acquire high signal-to-noise (SNR > 150) measurements in minutes, making it practical as a POC tool for many quantitative diagnostic measurements, including T2 relaxometry.

20.
Biomaterials ; 302: 122317, 2023 11.
Article in English | MEDLINE | ID: mdl-37717406

ABSTRACT

Damage that affects large volumes of skeletal muscle tissue can severely impact health, mobility, and quality-of-life. Efforts to restore muscle function by implanting tissue engineered muscle grafts at the site of damage have demonstrated limited restoration of force production. Various forms of mechanical and biochemical stimulation have been shown to have a potentially beneficial impact on graft maturation, vascularization, and innervation. However, these approaches yield unpredictable and incomplete recovery of functional mobility. Here we show that targeted actuation of implanted grafts, via non-invasive transcutaneous light stimulation of optogenetic engineered muscle, restores motor function to levels similar to healthy mice 2 weeks post-injury. Furthermore, we conduct phosphoproteomic analysis of actuated engineered muscle in vivo and in vitro to show that repeated muscle contraction alters signaling pathways that play key roles in skeletal muscle contractility, adaptation to injury, neurite growth, neuromuscular synapse formation, angiogenesis, and cytoskeletal remodeling. Our study uncovers changes in phosphorylation of several proteins previously unreported in the context of muscle contraction, revealing promising mechanisms for leveraging actuated muscle grafts to restore mobility after volumetric muscle loss.


Subject(s)
Muscular Diseases , Tissue Engineering , Mice , Animals , Muscle, Skeletal , Muscle Contraction/physiology , Prostheses and Implants
SELECTION OF CITATIONS
SEARCH DETAIL