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2.
NPJ Microgravity ; 9(1): 92, 2023 Dec 18.
Article En | MEDLINE | ID: mdl-38110398

The emerging arena of space exploration has created opportunities to study cancer cell biology in the environments of microgravity and hypergravity. Studying cellular behavior in altered gravity conditions has allowed researchers to make observations of cell function that would otherwise remain unnoticed. The patient-derived QNS108 brain tumor initiating cell line (BTIC), isolated from glioblastoma (GBM) tissue, was launched on a suborbital, parabolic rocket flight conducted by EXOS Aerospace Systems & Technologies. All biologicals and appropriate ground controls were secured post-launch and transported back to our research facility. Cells from the rocket-flight and ground-based controls were isolated from the culture containers and expanded on adherent flasks for two weeks. In vitro migration, proliferation, and stemness assays were performed. Following cell expansion, male nude mice were intracranially injected with either ground-control (GC) or rocket-flight (RF) exposed cells to assess tumorigenic capacity (n = 5 per group). Patient-derived QNS108 BTICs exposed to RF displayed more aggressive tumor growth than the GC cells in vitro and in vivo. RF cells showed significantly higher migration (p < 0.0000) and stemness profiles (p < 0.01) when compared to GC cells. Further, RF cells, when implanted in vivo in the brain of rodents had larger tumor-associated cystic growth areas (p = 0.00029) and decreased survival (p = 0.0172) as compared to those animals that had GC cells implanted.

3.
Front Oncol ; 13: 1295030, 2023.
Article En | MEDLINE | ID: mdl-38173841

High-grade gliomas are malignant brain tumors that are characteristically hard to treat because of their nature; they grow quickly and invasively through the brain tissue and develop chemoradiation resistance in adults. There is also a distinct lack of targeted treatment options in the pediatric population for this tumor type to date. Several approaches to overcome therapeutic resistance have been explored, including targeted therapy to growth pathways (ie. EGFR and VEGF inhibitors), epigenetic modulators, and immunotherapies such as Chimeric Antigen Receptor T-cell and vaccine therapies. One new promising approach relies on the timing of chemotherapy administration based on intrinsic circadian rhythms. Recent work in glioblastoma has demonstrated temporal variations in chemosensitivity and, thus, improved survival based on treatment time of day. This may be due to intrinsic rhythms of the glioma cells, permeability of the blood brain barrier to chemotherapy agents, the tumor immune microenvironment, or another unknown mechanism. We review the literature to discuss chronotherapeutic approaches to high-grade glioma treatment, circadian regulation of the immune system and tumor microenvironment in gliomas. We further discuss how these two areas may be combined to temporally regulate and/or improve the effectiveness of immunotherapies.

4.
Aging Cell ; 21(5): e13606, 2022 05.
Article En | MEDLINE | ID: mdl-35388616

Microglia have fundamental roles in health and disease; however, effects of age, sex, and genetic factors on human microglia have not been fully explored. We applied bulk and single-cell approaches to comprehensively characterize human microglia transcriptomes and their associations with age, sex, and APOE. We identified a novel microglial signature, characterized its expression in bulk tissue and single-cell microglia transcriptomes. We discovered microglial co-expression network modules associated with age, sex, and APOE-ε4 that are enriched for lipid and carbohydrate metabolism genes. Integrated analyses of modules with single-cell transcriptomes revealed significant overlap between age-associated module genes and both pro-inflammatory and disease-associated microglial clusters. These modules and clusters harbor known neurodegenerative disease genes including APOE, PLCG2, and BIN1. Meta-analyses with published bulk and single-cell microglial datasets further supported our findings. Thus, these data represent a well-characterized human microglial transcriptome resource and highlight age, sex, and APOE-related microglial immunometabolism perturbations with potential relevance in neurodegeneration.


Alzheimer Disease , Neurodegenerative Diseases , Alzheimer Disease/metabolism , Apolipoproteins E/genetics , Apolipoproteins E/metabolism , Humans , Microglia/metabolism , Neurodegenerative Diseases/genetics , Neurodegenerative Diseases/metabolism , Transcriptome/genetics
5.
J Neurosurg Pediatr ; 29(4): 444-453, 2022 04 01.
Article En | MEDLINE | ID: mdl-35090135

OBJECTIVE: Neonatal intraventricular hemorrhage (IVH) is a major cause of mortality and morbidity, particularly following premature birth. Even after the acute phase, posthemorrhagic hydrocephalus is a long-term complication, frequently requiring permanent ventriculoperitoneal shunt (VPS) placement. Currently, there are no risk classification methods integrating the constellation of clinical data to predict short- and long-term prognosis in neonatal IVH. To address this need, the authors developed a two-part machine learning approach for predicting short- and long-term outcomes after diagnosis of neonatal IVH. Integrating both maternal and neonatal characteristics, they developed a binary classifier to predict short-term mortality risk and a clinical scale to predict the long-term risk of VPS placement. METHODS: Neonates with IVH were identified from the Optum Clinformatics Data Mart administrative claims database. Matched maternal and childbirth characteristics were obtained for all patients. The primary endpoints of interest were short-term (30 day) mortality and long-term VPS placement. Classification of short-term mortality risk was evaluated using 5 different machine learning approaches and the best-performing method was validated using a withheld validation subset. Prediction of long-term shunt risk was performed using a multivariable Cox regression model with stepwise variable selection, which was subsequently converted to an easily applied integer risk scale. RESULTS: A total of 5926 neonates with IVH were identified. Most patients were born before 32 weeks' gestation (67.2%) and with low birth weight (81.2%). Empirical 30-day mortality risk was 10.9% across all IVH grades and highest among grade IV IVH (34.3%). Among the neonates who survived > 30 days, actuarial 12-month postdiagnosis risk of shunt placement was 5.4% across all IVH grades and 31.3% for grade IV IVH. The optimal short-term risk classifier was a random forest model achieving an area under the receiver operating characteristic curve of 0.882 with important predictors ranging from gestational age to diverse comorbid medical conditions. Selected features for long-term shunt risk stratification were IVH grade, respiratory distress syndrome, disseminated intravascular coagulation, and maternal preeclampsia or eclampsia. An integer risk scale, termed the Shunt Prediction After IVH in Neonates (SPAIN) scale, was developed from these 4 features, which, evaluated on withheld cases, demonstrated improved risk stratification compared with IVH grade alone (Harrell's concordance index 0.869 vs 0.852). CONCLUSIONS: In a large cohort of neonates with IVH, the authors developed a two-pronged, integrated, risk classification approach to anticipate short-term mortality and long-term shunt risk. The application of such approaches may improve the prognostication of outcomes and identification of higher-risk individuals who warrant careful surveillance and early intervention.


Hydrocephalus , Infant, Premature, Diseases , Cerebral Hemorrhage/complications , Cerebral Hemorrhage/surgery , Female , Humans , Hydrocephalus/complications , Hydrocephalus/surgery , Infant, Newborn , Infant, Premature, Diseases/surgery , Pregnancy , Retrospective Studies , Ventriculoperitoneal Shunt/adverse effects
6.
Obstet Med ; 14(3): 193-196, 2021 Sep.
Article En | MEDLINE | ID: mdl-34646351

Lecithin-cholesterol acyltransferase (LCAT) deficiency is a rare autosomal recessive condition affecting lipid metabolism with a prevalence of less than 1:1,000,000. Described here is the case of a 29-year-old pregnant woman with a diagnosis of LCAT deficiency (c.140G>A in exon 4), who had three episodes of hypertriglyceridemia-induced pancreatitis and nephrotic-range proteinuria throughout the pregnancy. Furthermore, fetal ultrasounds carried out during the second and third trimester revealed a steady reduction in fetal growth rate, and fetal growth restriction (FGR) was diagnosed. The woman underwent an elective caesarean section at 33 weeks of gestation and delivered a healthy neonate. This case report adds knowledge of the natural history of LCAT deficiency during pregnancy and will be useful in future patient management.

7.
Mol Cancer Ther ; 20(12): 2585-2597, 2021 12.
Article En | MEDLINE | ID: mdl-34465594

Glioblastoma (GBM) is the most common primary brain cancer in adults where tumor cell heterogeneity and sex differences influence clinical outcomes. Here, we functionally characterize three male and three female patient-derived GBM cell lines, identify protumorigenic BTICs, and create novel male and female preclinical models of GBM. Cell lines were evaluated on the following features: proliferation, stemness, migration, tumorigenesis, clinical characteristics, and sensitivity to radiation, TMZ, rhTNFSF10 (rhTRAIL), and rhBMP4 All cell lines were classified as GBM according to epigenetic subtyping, were heterogenous and functionally distinct from one another, and re-capitulated features of the original patient tumor. In establishing male and female preclinical models, it was found that two male-derived GBM cell lines (QNS108 and QNS120) and one female-derived GBM cell line (QNS315) grew at a faster rate in female mice brains. One male-derived GBM cell line (QNS108) decreased survival in female mice in comparison with male mice. However, no survival differences were observed for mice injected with a female-derived cell line (QNS315). In summary, a panel of six GBM patient-derived cell lines were functionally characterized, and it was shown that BTIC lines can be used to construct sex-specific models with differential phenotypes for additional studies.


Neoplastic Stem Cells/metabolism , Aged , Animals , Brain Neoplasms/mortality , Brain Neoplasms/pathology , Cell Line, Tumor , Cell Proliferation , Female , Glioblastoma/mortality , Glioblastoma/pathology , Humans , Male , Mice , Middle Aged , Sex Characteristics , Survival Analysis
8.
World Neurosurg ; 148: e282-e293, 2021 04.
Article En | MEDLINE | ID: mdl-33412316

OBJECTIVE: In the wake of the COVID-19 pandemic, the Centers for Medicare & Medicaid Services (CMS) has recommended the temporary cessation of all elective surgeries. The effects on patients' interest of elective neurosurgical procedures are currently unexplored. METHODS: Using Google Trends, search terms of 7 different neurosurgical procedure categories (trauma, spine, tumor, movement disorder, epilepsy, endovascular, and miscellaneous) were assessed in terms of relative search volume (RSV) between January 2015 and September 2020. Analyses of search terms were performed for over the short term (February 18, 2020, to April 18, 2020), intermediate term (January 1, 2020, to May 31, 2020), and long term (January 2015 to September 2020). State-level interest during phase I reopening (April 28, 2020, to May 31, 2020) was also evaluated. RESULTS: In the short term, RSVs of 4 categories (epilepsy, movement disorder, spine, and tumor) were significantly lower in the post-CMS announcement period. In the intermediate term, RSVs of 5 categories (miscellaneous, epilepsy, movement disorder, spine, and tumor) were significantly lower in the post-CMS announcement period. In the long term, RSVs of nearly all categories (endovascular, epilepsy, miscellaneous, movement disorder, spine, and tumor) were significantly lower in the post-CMS announcement period. Only the movement disorder procedure category had significantly higher RSV in states that reopened early. CONCLUSIONS: With the recommendation for cessation of elective surgeries, patient interests in overall elective neurosurgical procedures have dropped significantly. With gradual reopening, there has been a resurgence in some procedure types. Google Trends has proven to be a useful tracker of patient interest and may be used by neurosurgical departments to facilitate outreach strategies.


Elective Surgical Procedures , Information Seeking Behavior , Internet , Neurosurgical Procedures , Search Engine , Brain Neoplasms/surgery , COVID-19 , Cerebrovascular Disorders/surgery , Craniocerebral Trauma/surgery , Deep Brain Stimulation , Endovascular Procedures , Epilepsy/surgery , Humans , Movement Disorders/therapy , Prosthesis Implantation , SARS-CoV-2 , Spinal Diseases/surgery
9.
Gac Med Mex ; 156(5): 446-453, 2020.
Article En | MEDLINE | ID: mdl-33372929

In recent years, the introduction of a series of biological drugs for the treatment of psoriasis has considerably increased the therapeutic armamentarium of doctors, and thus a strongly positive impact on the control of this condition has been achieved. With the purpose to provide the best recommendations for the use of these biological agents in patients with psoriasis, the Mexican group of psoriasis experts, PSOMEX, has developed recommendations in order to improve the understanding and therapeutic positioning of this type of medications.


En los últimos años, la introducción de diversos medicamentos biológicos para el tratamiento de la psoriasis ha aumentado considerablemente el arsenal terapéutico del médico, con lo cual se ha logrado un fuerte impacto positivo en el control de la enfermedad. Con el fin de proveer de las mejores recomendaciones para el uso de estos biológicos en los pacientes afectados de psoriasis, el grupo mexicano de expertos en psoriasis PSOMEX ha formulado recomendaciones para mejorar la comprensión y el posicionamiento terapéutico de este tipo de medicamentos.


Biological Factors/therapeutic use , Psoriasis/therapy , Age Factors , Female , Humans , Male , Mexico , Pregnancy , Pregnancy Complications/therapy , Societies, Medical , Tumor Necrosis Factor-alpha/antagonists & inhibitors
10.
Gac. méd. Méx ; 156(5): 454-462, sep.-oct. 2020. tab
Article Es | LILACS | ID: biblio-1249945

Resumen En los últimos años, la introducción de diversos medicamentos biológicos para el tratamiento de la psoriasis ha aumentado considerablemente el arsenal terapéutico del médico, con lo cual se ha logrado un fuerte impacto positivo en el control de la enfermedad. Con el fin de proveer de las mejores recomendaciones para el uso de estos biológicos en los pacientes afectados de psoriasis, el grupo mexicano de expertos en psoriasis PSOMEX ha formulado recomendaciones para mejorar la comprensión y el posicionamiento terapéutico de este tipo de medicamentos.


Abstract In recent years, the introduction of a series of biological drugs for the treatment of psoriasis has considerably increased the therapeutic armamentarium of doctors, and thus a strongly positive impact on the control of this condition has been achieved. With the purpose to provide the best recommendations for the use of these biological agents in patients with psoriasis, the Mexican group of psoriasis experts, PSOMEX, has developed recommendations in order to improve the understanding and therapeutic positioning of this type of medications.


Humans , Male , Female , Pregnancy , Psoriasis/therapy , Biological Factors/therapeutic use , Pregnancy Complications/therapy , Societies, Medical , Age Factors , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Mexico
11.
Sci Rep ; 10(1): 13963, 2020 08 18.
Article En | MEDLINE | ID: mdl-32811891

How organisms maintain cell size homeostasis is a long-standing problem that remains unresolved, especially in multicellular organisms. Recent experiments in diverse animal cell types demonstrate that within a cell population, cellular proliferation is low for small and large cells, but high at intermediate sizes. Here we use mathematical models to explore size-control strategies that drive such a non-monotonic profile resulting in the proliferation capacity being maximized at a target cell size. Our analysis reveals that most models of size control yield proliferation capacities that vary monotonically with cell size, and non-monotonicity requires two key mechanisms: (1) the growth rate decreases with increasing size for excessively large cells; and (2) cell division occurs as per the Adder model (division is triggered upon adding a fixed size from birth), or a Sizer-Adder combination. Consistent with theory, Jurkat T cell growth rates increase with size for small cells, but decrease with size for large cells. In summary, our models show that regulation of both growth and cell-division timing is necessary for size control in animal cells, and this joint mechanism leads to a target cell size where cellular proliferation capacity is maximized.


Cell Proliferation/physiology , Homeostasis/physiology , Animals , Cell Division/physiology , Cell Enlargement , Cell Size , Computational Biology/methods , Humans , Mitosis , Models, Biological , Models, Theoretical
12.
Rev. Soc. Peru. Med. Interna ; 33(1): 25-30, ene.-mar. 2020. ilus, tab
Article Es | LILACS | ID: biblio-1116184

Varón de 77 años de edad, con antecedentes de insuficiencia cardiaca y fibrilación auricular recibiendo warfarina, hipotiroidismo, diabetes mellitus e hiperuricemia, con historia de un año de lesiones dérmicas eritematosas y descamativas en el tronco, pruriginosas y con moderada eosinofilia recurrente. Después de descartarse causas alérgicas, parasitarias, autoinmunes y neoplásicas, se hizo el diagnóstico de síndrome hipereosinofílico idiopático. Recibió tratamiento con prednisona e hidroxiurea, consiguiéndose una remisión completa de la eosinofilia y mejoría progresiva de las lesiones dérmicas. (AU)


A 77-year-old male, with a history of heart failure and atrial fibrillation receiving warfarin, hypothyroidism, diabetes mellitus and hyperuricaemia, with a one-year history of erythematous and desquamative skin lesions in the trunk, pruritic and moderate recurrent eosinophilia. After allergic, parasitic, autoimmune and neoplastic causes were ruled out, the diagnosis of idiopathic hypereosinophilic syndrome was done. He was treated with prednisone and hydroxyurea, resulting in complete remission of eosinophilia and progressive improvement of dermal lesions. (AU)


Humans , Male , Aged , Skin , Prednisone , Hypereosinophilic Syndrome , Eosinophilia
13.
ACS Biomater Sci Eng ; 6(5): 2943-2955, 2020 05 11.
Article En | MEDLINE | ID: mdl-33463272

Glioblastoma (GBM) is the most devastating brain cancer, and cures remain elusive with currently available neurosurgical, pharmacological, and radiation approaches. While retrovirus- and adenovirus-mediated suicide gene therapy using DNA encoding herpes simplex virus-thymidine kinase (HSV-tk) and prodrug ganciclovir has been suggested as a promising strategy, a nonviral approach for treatment in an orthotopic human primary brain tumor model has not previously been demonstrated. Delivery challenges include nanoparticle penetration through brain tumors, efficient cancer cell uptake, endosomal escape to the cytosol, and biodegradability. To meet these challenges, we synthesized poly(ethylene glycol)-modified poly(beta-amino ester) (PEG-PBAE) polymers to improve extracellular delivery and coencapsulated plasmid DNA with end-modified poly(beta-amino ester) (ePBAE) polymers to improve intracellular delivery as well. We created and evaluated a library of PEG-PBAE/ePBAE nanoparticles (NPs) for effective gene therapy against two independent primary human stem-like brain tumor initiating cells, a putative target to prevent GBM recurrence. The optimally engineered PEG-PBAE/ePBAE NP formulation demonstrated 54 and 82% transfection efficacies in GBM1A and BTIC375 cells respectively, in comparison to 37 and 66% for optimized PBAE NPs without PEG. The leading PEG-PBAE NP formulation also maintained sub-250 nm particle size up to 5 h, while PBAE NPs without PEG showed aggregation over time to micrometer-sized complexes. The comparative advantage demonstrated in vitro successfully translated into improved in vivo diffusion, with a higher amount of PEG-PBAE NPs penetrating to a distance of 2 mm from the injection site. A significant increase in median survival from 53.5 to 67 days by PEG-PBAE/pHSV-tk NP and systemic ganciclovir treatment compared to a control group in orthotopic murine model of human glioblastoma demonstrates the potential of PEG-PBAE-based NPs as an effective gene therapy platform for the treatment of human brain tumors.


Glioblastoma , Nanoparticles , Animals , Brain , Cell Line, Tumor , Esters , Genetic Therapy , Glioblastoma/genetics , Heterografts , Humans , Mice , Polyethylene Glycols , Polymers
16.
Mol Med Rep ; 20(3): 2189-2198, 2019 Sep.
Article En | MEDLINE | ID: mdl-31257515

Recent studies demonstrated that the expression of coxsackievirus and adenovirus receptor (CAR) is implicated in the pathophysiology of myocarditis. The aim of the present study was to assess the association between active and borderline myocarditis and CAR expression in endomyocardial tissues, and analyze the association between CAR expression and treatment response. An analytic, cross­sectional, retrospective study was performed in 26 patients with myocarditis and 10 control subjects without heart disease. Myocardial biopsies were obtained and CAR transcription was measured by reverse transcription­quantitative polymerase chain reaction analysis. The association between CAR mRNA levels and the response to immunosuppressive or conventional therapy (treatment responders, n=17; non­responders, n=9) or with the type of histological myocarditis (active myocarditis, n=16; borderline myocarditis, n=10) was analyzed. CAR transcription levels were significantly lower (P=0.012) in patients with myocarditis compared with controls, and a significant decrease was observed (P=0.023) in CAR mRNA levels among patients with borderline myocarditis compared with the no myocarditis group. Patients responding to therapy exhibited higher CAR mRNA levels (P=0.036) compared with patients not responding to treatment, as evaluated based on clinical and echocardiographic criteria (immunosuppressive therapy, n=8; conventional therapy, n=1). Myocarditis in non­responders was associated with fewer clinical manifestations and lower CAR mRNA levels. A significant difference was only found regarding the use of oral steroids in patients with active myocarditis who responded to treatment (P=0.02), with no difference in borderline myocarditis. In conclusion, the transcriptional level of CAR is low in the endomyocardial tissue of patients with myocarditis, and it is lower in borderline myocarditis and in non­responder patients. These findings may enable early identification of patients who may benefit from treatment and timely determination of prognosis.


Coxsackie and Adenovirus Receptor-Like Membrane Protein/genetics , Myocarditis/genetics , Myocardium/pathology , Adult , Cross-Sectional Studies , Down-Regulation , Female , Humans , Male , Middle Aged , Myocarditis/pathology , Myocardium/metabolism , RNA, Messenger/genetics , Young Adult
17.
Org Chem Front ; 6(9): 1361-1366, 2019 May 07.
Article En | MEDLINE | ID: mdl-31178993

The dynamics of guests in molecular encapsulation complexes have been studied extensively in solution, but the corresponding behavior of those guests when the capsules are present in the solid state is not as well understood. Here we report on comparative solution 1H and solid-state 2H NMR measurements of encapsulation complexes of fluorene(-d 2), fluoranthene(-d 10), and pyrene-(-d 10) in pyrogallol[4]arene hexamers assembled in the solid state by ball milling. In solution, the 1H spectra show that these rigid guests tumble and exchange positions quickly within the capsules' interiors, with the exception of pyrene, which has slower tumbling and positional exchange. Static solid-state 2H NMR using the deuterated guests shows that, when the capsules are in the solid state, their guests retain the liquid state-like dynamics observed for the capsules in solution. When the pyrogallol[4]arene hexamers' pendant decyl groups were substituted with propyl groups, guest dynamics in the solid state were slowed. We propose that these pendant alkyl groups form an interdigitated and dynamic waxy domain surrounding the capsules in the solid state, and that the greater mobility of the decyl groups is translated across the walls of the host, resulting in more rapid guest dynamics in the capsules' interiors.

19.
PLoS One ; 13(11): e0206700, 2018.
Article En | MEDLINE | ID: mdl-30408070

Clinical trials are necessary in order to develop treatments for diseases; however, they can often be costly, time consuming, and demanding to the patients. This paper summarizes several common methods used for optimal design that can be used to address these issues. In addition, we introduce a novel method for optimizing experiment designs applied to HIV 2-LTR clinical trials. Our method employs Bayesian techniques to optimize the experiment outcome by maximizing the Expected Kullback-Leibler Divergence (EKLD) between the a priori knowledge of system parameters before the experiment and the a posteriori knowledge of the system parameters after the experiment. We show that our method is robust and performs equally well if not better than traditional optimal experiment design techniques.


HIV Long Terminal Repeat/drug effects , HIV Long Terminal Repeat/genetics , HIV/drug effects , HIV/genetics , Algorithms , Bayes Theorem , Clinical Trials as Topic/methods , Clinical Trials as Topic/statistics & numerical data , Computer Simulation , HIV/physiology , HIV Infections/therapy , HIV Infections/virology , HIV Long Terminal Repeat/physiology , Humans , Immunotherapy, Adoptive , Markov Chains , Models, Biological , Models, Statistical , Monte Carlo Method , RNA, Viral/biosynthesis , RNA, Viral/genetics , Research Design , Virus Replication/drug effects , Virus Replication/genetics
20.
Curr Opin Syst Biol ; 8: 109-116, 2018 Apr.
Article En | MEDLINE | ID: mdl-29862376

Growth of a cell and its subsequent division into daughters is a fundamental aspect of all cellular living systems. During these processes, how do individual cells correct size aberrations so that they do not grow abnormally large or small? How do cells ensure that the concentration of essential gene products are maintained at desired levels, in spite of dynamic/stochastic changes in cell size during growth and division? Both these questions have fascinated researchers for over a century. We review how advances in singe-cell technologies and measurements are providing unique insights into these questions across organisms from prokaryotes to human cells. More specifically, diverse strategies based on timing of cell-cycle events, regulating growth, and number of daughters are employed to maintain cell size homeostasis. Interestingly, size homeostasis often results in size optimality - proliferation of individual cells in a population is maximized at an optimal cell size. We further discuss how size-dependent expression or gene-replication timing can buffer concentration of a gene product from cell-to-cell size variations within a population. Finally, we speculate on an intriguing hypothesis that specific size control strategies may have evolved as a consequence of gene-product concentration homeostasis.

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