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1.
Nat Commun ; 15(1): 538, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38225226

RESUMO

Hematopoietic stem cells (HSCs) are capable of regenerating the blood system, but the instructive cues that direct HSCs to regenerate particular lineages lost to the injury remain elusive. Here, we show that iron is increasingly taken up by HSCs during anemia and induces erythroid gene expression and regeneration in a Tet2-dependent manner. Lineage tracing of HSCs reveals that HSCs respond to hemolytic anemia by increasing erythroid output. The number of HSCs in the spleen, but not bone marrow, increases upon anemia and these HSCs exhibit enhanced proliferation, erythroid differentiation, iron uptake, and TET2 protein expression. Increased iron in HSCs promotes DNA demethylation and expression of erythroid genes. Suppressing iron uptake or TET2 expression impairs erythroid genes expression and erythroid differentiation of HSCs; iron supplementation, however, augments these processes. These results establish that the physiological level of iron taken up by HSCs has an instructive role in promoting erythroid-biased differentiation of HSCs.


Assuntos
Anemia , Dioxigenases , Humanos , Baço , Células-Tronco Hematopoéticas/metabolismo , Diferenciação Celular , Ferro/metabolismo , Anemia/metabolismo , Células Eritroides , Proteínas de Ligação a DNA/metabolismo , Dioxigenases/metabolismo
2.
Cureus ; 15(11): e49005, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38111448

RESUMO

Antipsychotics are frequently used to treat psychiatric disorders and have been associated with weight gain. Mental disorders are likely to reduce patients' quality of life. Unhealthy lifestyles such as reduced physical activity, sleep disturbances, and irregular diets can lead to weight gain. Herein, we report two cases of schizophrenia and bipolar disorder who had a 10-kg gain in weight in six months with the administration of lurasidone and valproic acid. Lurasidone has fewer side effects, such as weight gain and somnolence. However, concomitant use of sedating antipsychotics or mood stabilizers in the acute phase and multiple doses increase the risk of weight gain. Additionally, various factors, including psychiatric symptoms and lifestyle changes, are believed to contribute to weight gain, and a comprehensive approach should be followed.

4.
J Affect Disord ; 339: 538-546, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37467797

RESUMO

BACKGROUND: MicroRNAs (miRNAs) and circulating cell-free mitochondrial DNA (ccf-mtDNA) have attracted interest as biological markers of affective disorders. In response to stress, it is known that miRNAs in mitochondria diffuse out of the cytoplasm alongside mtDNA; however, this process has not yet been identified. We hypothesized that miRNAs derived from specific cell nuclei cause mitochondrial damage and mtDNA fragmentation under MDD-associated stress conditions. METHODS: A comprehensive analysis of the plasma miRNA levels and quantification of the plasma ccf-mtDNA copy number were performed in 69 patients with depression to determine correlations and identify genes and pathways interacting with miRNAs. The patients were randomly assigned to receive either selective serotonin reuptake inhibitors (SSRI) or mirtazapine. Their therapeutic efficacy over four weeks was evaluated in relation to miRNAs correlated with ccf-mtDNA copy number. RESULTS: The expression levels of the five miRNAs showed a significant positive correlation with the ccf-mtDNA copy number after correcting for multiple testing. These miRNAs are involved in gene expression related to thyroid hormone synthesis, the Hippo signaling pathway, vasopressin-regulated water reabsorption, and lysine degradation. Of these five miRNAs, miR-6068 and miR-4708-3p were significantly associated with the SSRI and mirtazapine treatment outcomes, respectively. LIMITATIONS: This study did not show comparison with a healthy group. CONCLUSIONS: The expression levels of specific miRNAs were associated with ccf-mtDNA copy number in untreated depressed patients; moreover, these miRNAs were linked to antidepressant treatment outcomes. These findings are expected to lead to the elucidation of new pathological mechanism of depression.


Assuntos
Ácidos Nucleicos Livres , Transtorno Depressivo Maior , MicroRNAs , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , DNA Mitocondrial , Transtorno Depressivo Maior/tratamento farmacológico , Transtorno Depressivo Maior/genética , Mirtazapina/uso terapêutico , Depressão , Ácidos Nucleicos Livres/genética , Ácidos Nucleicos Livres/metabolismo , Mitocôndrias/metabolismo , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico
5.
Intern Med ; 62(1): 107-111, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35650129

RESUMO

Most patients with hereditary spherocytosis (HS) have a family history of disease, while those without such a history are difficult to diagnose. We herein report a case of HS with no family history harboring a novel heterozygous mutation of SPTA1, c.2161G>A (p.E721K), and a homozygous polymorphism of UGT1A1*6. In silico analyses suggested that the mutation might contribute to the pathogenesis of HS. The coexistence of HS and Gilbert's syndrome increases the risk of gallstones. Therefore, splenectomy, alone or in combination with cholecystectomy, is recommended. The determination of genetic diathesis provides useful information for the management of hemolytic anemia.


Assuntos
Doença de Gilbert , Esferocitose Hereditária , Humanos , Doença de Gilbert/complicações , Doença de Gilbert/genética , Doença de Gilbert/diagnóstico , Mutação/genética , Esferocitose Hereditária/complicações , Esferocitose Hereditária/genética , Esferocitose Hereditária/diagnóstico , Heterozigoto , Glucuronosiltransferase/genética , Polimorfismo Genético , Proteínas do Citoesqueleto/genética
6.
J Clin Exp Hematop ; 62(4): 238-241, 2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36436931

RESUMO

Richter's syndrome (RS) of the central nervous system (CNS) is known to have an extremely poor prognosis. Ibrutinib has been reported to have some activity in patients with RS, despite its poor prognosis. Although ibrutinib crosses the blood-brain barrier, its efficacy in RS patients with CNS involvement remains unknown. Here, we report a case of RS isolated in the CNS that was confirmed to be clonally related to chronic lymphocytic leukemia (CLL) by immunoglobulin heavy chain gene analysis. Although the median survival of patients with RS clonally related to CLL was significantly shorter than that of patients with RS clonally unrelated to CLL, the patient received ibrutinib monotherapy without experiencing any significant adverse events, and the disease remained stable with ibrutinib until 6 weeks later. Following whole-brain radiation therapy (40 Gy in 20 fractions) with dexamethasone, the patient has survived for five months after diagnosis. Thus, ibrutinib may be a safe and effective therapeutic option for patients with RS and CNS involvement.


Assuntos
Neoplasias Encefálicas , Leucemia Linfocítica Crônica de Células B , Linfoma Difuso de Grandes Células B , Humanos , Leucemia Linfocítica Crônica de Células B/genética , Irradiação Craniana , Linfoma Difuso de Grandes Células B/genética , Sistema Nervoso Central
7.
Cell Rep ; 40(9): 111260, 2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-36044861

RESUMO

Hematopoiesis was considered a hierarchical stepwise process but was revised to a continuous process following single-cell RNA sequencing. However, the uncertainty or fluctuation of single-cell transcriptome dynamics during differentiation was not considered, and the dendritic cell (DC) pathway in the lymphoid context remains unclear. Here, we identify human B-plasmacytoid DC (pDC) bifurcation as large fluctuating transcriptome dynamics in the putative B/NK progenitor region by dry and wet methods. By converting splicing kinetics into diffusion dynamics in a deep generative model, our original computational methodology reveals strong fluctuation at B/pDC bifurcation in IL-7Rα+ regions, and LFA-1 fluctuates positively in the pDC direction at the bifurcation. These expectancies are validated by the presence of B/pDC progenitors in the IL-7Rα+ fraction and preferential expression of LFA-1 in pDC-biased progenitors with a niche-like culture system. We provide a model of fluctuation-based differentiation, which reconciles continuous and discrete models and is applicable to other developmental systems.


Assuntos
Diferenciação Celular , Células Dendríticas , Antígeno-1 Associado à Função Linfocitária , Diferenciação Celular/genética , Células Dendríticas/metabolismo , Hematopoese , Humanos , Antígeno-1 Associado à Função Linfocitária/genética , Antígeno-1 Associado à Função Linfocitária/metabolismo , Transcriptoma/genética
9.
Rinsho Ketsueki ; 63(1): 26-30, 2022.
Artigo em Japonês | MEDLINE | ID: mdl-35135948

RESUMO

At initial diagnosis, central nervous system (CNS) involvement in acute promyelocytic leukemia (APL) is rare. Here, we report a case of newly diagnosed APL with CNS involvement that was successfully treated with all-trans retinoic acid (ATRA)-combined chemotherapy. A 64-year-old woman was referred to our hospital to evaluate a bleeding tendency, and she was diagnosed with APL. Induction chemotherapy with ATRA via a nasogastric tube was initiated under mechanical ventilation because of respiratory failure and disturbance of consciousness. Although her respiratory condition improved a few days after initiating treatment, the disturbance of consciousness remained. Brain magnetic resonance imaging showed mixed signals of tumor infiltration and acute cerebral infarction with a focus on the right cerebellum. The patient was diagnosed with CNS involvement of APL and acute cerebral infarction. Three months after the initiation of induction therapy, her consciousness improved along with the reduction in CNS involvement, and complete molecular remission was achieved. Thus, patients with APL can have CNS involvement at initial diagnosis. Administering ATRA via nasogastric tube can be a good therapeutic option in patients with difficulty swallowing due to disturbance of consciousness.


Assuntos
Leucemia Promielocítica Aguda , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Sistema Nervoso Central , Feminino , Humanos , Quimioterapia de Indução , Leucemia Promielocítica Aguda/complicações , Leucemia Promielocítica Aguda/tratamento farmacológico , Pessoa de Meia-Idade , Indução de Remissão , Tretinoína/uso terapêutico
10.
World J Biol Psychiatry ; 23(10): 785-793, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35193470

RESUMO

OBJECTIVES: The response to antidepressants varies significantly among individuals and is difficult to predict before treatment. In this randomised control trial, we explored cytokines that correlate with the therapeutic effect of mirtazapine (MIR) and selective serotonin reuptake inhibitors (SSRIs) and whether they could be predictors of remission for each antidepressant. METHODS: Plasma cytokines, such as tumour necrosis factor-α (TNF-α), interleukin (IL)-1ß, IL-2, IL-4, IL-6, IL-8, and granulocyte-macrophage colony-stimulating factor (GM-CSF) were assayed in 95 participants before medication and assayed by the enzyme-linked immunosorbent assay. The Hamilton Rating Scale for Depression assessed depressive symptoms over 4 weeks. RESULTS: In the SSRI group, the baseline GM-CSF level was significantly higher in the remission group than in the non-remission group (p = .022). In the MIR group, the baseline level of TNF-α was significantly higher (p = .039) and IL-2 was lower (p = .032) in the remission group than in the non-remission group. In patients prescribed with MIR, the cut-off values of TNF-α (10.035 pg/mL) and IL-2 (1.170 pg/mL) calculated from the receiver operating characteristic curve suggested that the remission rate, which corresponds to a positive predictive value, could be increased from 31.3% to 60.0% and 50.0%, respectively. For those prescribed with SSRIs, the remission rate was 37.0% and using the cut-off value of GM-CSF (0.205 pg/mL), the remission rate could be almost doubled to 70%. CONCLUSIONS: Our study shows that pre-treatment plasma concentrations of TNF-α, IL-2, and GM-CSF may suggest the predictability of remission by SSRIs or MIR.


Assuntos
Citocinas , Fator Estimulador de Colônias de Granulócitos e Macrófagos , Humanos , Fator de Necrose Tumoral alfa , Interleucina-2 , Inibidores Seletivos de Recaptação de Serotonina , Mirtazapina , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico
12.
J Affect Disord ; 299: 644-651, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34715189

RESUMO

BACKGROUND: Patients with bipolar disorder (BD) have increased plasma IL-6 levels, which are higher in depressed BD (dBD) than remitted BD (rBD). However, the mechanism that differentiates the cytokine levels between dBD and rBD is not understood. First, we determined whether brain-derived mtDNA can be detected in plasma using neuron-specific mutant Polg1 transgenic (Tg) mice. Second, we investigated whether the plasma circulating cell-free mitochondrial DNA (ccf-mtDNA) differentiate the cytokine levels between dBD and rBD. METHODS: Mouse plasma ccf-mtDNA levels were measured using real-time PCR targeting two regions of the mtDNA (CO1 and d-loop) in Tg mice and non-Tg littermates. Human plasma ccf-mtDNA levels were measured using real-time PCR targeting two regions of the mtDNA (ND1 and ND4) and IL-6 levels were evaluated in 10 patients in different states (depressed and remitted) of BD in a longitudinal manner and 10 healthy controls. RESULTS: The mouse plasma CO1/D-loop ratio was significantly lower in Tg than non-Tg mice (P = 0.0029). Human plasma ccf-mtDNA copy number, ND4/ND1 ratio, and IL-6 levels were not significantly different between dBD and rBD. Human plasma ccf-mtDNA levels showed a nominal significant correlation with delusional symptoms (P = 0.033, ρ = 0.68). LIMITATIONS: A larger sample size is required to generalize the results and to determine whether plasma ccf-mtDNA is associated with systemic inflammation. CONCLUSIONS: Tg mice revealed that brain-derived mtDNA could be present in peripheral blood. The present findings did not coincide with our hypothesis that plasma ccf-mtDNA differentiates the cytokine levels between dBD and rBD.


Assuntos
Transtorno Bipolar , DNA Mitocondrial , Animais , Transtorno Bipolar/genética , Variações do Número de Cópias de DNA , DNA Mitocondrial/genética , Humanos , Interleucina-6/genética , Camundongos , Mitocôndrias
13.
Sci Rep ; 11(1): 22446, 2021 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-34789822

RESUMO

The first polyhydroxyalkanoate (PHA) block copolymer poly(2-hydroxybutyrate-b-3-hydroxybutyrate) [P(2HB-b-3HB)] was previously synthesized using engineered Escherichia coli expressing a chimeric PHA synthase PhaCAR with monomer sequence-regulating capacity. In the present study, the physical properties of the block copolymer and its relevant random copolymer P(2HB-ran-3HB) were evaluated. Stress-strain tests on the P(88 mol% 2HB-b-3HB) film showed an increasing stress value during elongation up to 393%. In addition, the block copolymer film exhibited slow contraction behavior after elongation, indicating that P(2HB-b-3HB) is an elastomer-like material. In contrast, the P(92 mol% 2HB-ran-3HB) film, which was stretched up to 692% with nearly constant stress, was stretchable but not elastic. The differential scanning calorimetry and wide-angle X-ray diffraction analyses indicated that the P(2HB-b-3HB) contained the amorphous P(2HB) phase and the crystalline P(3HB) phase, whereas P(2HB-ran-3HB) was wholly amorphous. Therefore, the elasticity of P(2HB-b-3HB) can be attributed to the presence of the crystalline P(3HB) phase and a noncovalent crosslinked structure by the crystals. These results show the potential of block PHAs as elastic materials.

14.
Case Rep Hematol ; 2021: 5527725, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34123441

RESUMO

Sézary syndrome is a rare leukemic type of cutaneous T-cell lymphoma characterized by the presence of neoplastic T cells with cerebriform nuclei (Sézary cells) in the skin, lymph nodes, and peripheral blood. Typical Sézary cells have a CD3+CD4+CD8- phenotype; however, in cases of the aberrant loss of antigens on Sézary cells, especially the loss of critically important T-cell antigens such as CD4, there is a possibility of misdiagnosing the disease or underestimating the tumor burden of the disease. Here, we report a rare case of Sézary syndrome with CD4/CD8 double-negative Sézary cells in the peripheral blood. Most of the Sézary cells in the peripheral blood had lost CD4 expression, and we diagnosed the disease and evaluated the tumor burden by multicolor flow cytometry. Intriguingly, the Sézary cells showed a typical CD4+CD8-CD7- phenotype in the skin even though the cells in the peripheral blood lacked CD4. The patient responded well to treatment with bexarotene and narrow-band ultraviolet B therapy. Analysis by multicolor flow cytometry is essential to diagnose this rare type of Sézary syndrome and evaluate the tumor burden.

15.
Front Bioeng Biotechnol ; 9: 618259, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33718339

RESUMO

Production of medium chain-length poly(3-hydroxyalkanoates) [PHA] polymers with tightly defined compositions is an important area of research to expand the application and improve the properties of these promising biobased and biodegradable materials. PHA polymers with homopolymeric or defined compositions exhibit attractive material properties such as increased flexibility and elasticity relative to poly(3-hydroxybutyrate) [PHB]; however, these polymers are difficult to biosynthesize in native PHA-producing organisms, and there is a paucity of research toward developing high-density cultivation methods while retaining compositional control. In this study, we developed and optimized a fed-batch fermentation process in a stirred tank reactor, beginning with the biosynthesis of poly(3-hydroxydecanoate) [PHD] from decanoic acid by ß-oxidation deficient recombinant Escherichia coli LSBJ using glucose as a co-substrate solely for growth. Bacteria were cultured in two stages, a biomass accumulation stage (37°C, pH 7.0) with glucose as the primary carbon source and a PHA biosynthesis stage (30°C, pH 8.0) with co-feeding of glucose and a fatty acid. Through iterative optimizations of semi-defined media composition and glucose feed rate, 6.0 g of decanoic acid was converted to PHD with an 87.5% molar yield (4.54 g L-1). Stepwise increases in the amount of decanoic acid fed during the fermentation correlated with an increase in PHD, resulting in a final decanoic acid feed of 25 g converted to PHD at a yield of 89.4% (20.1 g L-1, 0.42 g L-1 h-1), at which point foaming became uncontrollable. Hexanoic acid, octanoic acid, 10-undecenoic acid, and 10-bromodecanoic acid were all individually supplemented at 20 g each and successfully polymerized with yields ranging from 66.8 to 99.0% (9.24 to 18.2 g L-1). Using this bioreactor strategy, co-fatty acid feeds of octanoic acid/decanoic acid and octanoic acid/10-azidodecanoic acid (8:2 mol ratio each) resulted in the production of their respective copolymers at nearly the same ratio and at high yield, demonstrating that these methods can be used to control PHA copolymer composition.

16.
Int J Hematol ; 114(1): 129-135, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33646526

RESUMO

Monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL) is a rare subtype of intestinal T-cell lymphoma that occurs mostly in Asia. CHOP-like therapy is usually selected, but the prognosis is very poor. This report concerns a 43-year-old woman with newly diagnosed stage IVA MEITL. The patient obtained a partial response after 4 cycles of GDP (gemcitabine, dexamethasone, cisplatin) and achieved a complete response (CR) after cord blood transplantation (CBT) conditioned with total body irradiation, cyclophosphamide, and cytarabine. Seven months after transplantation, the patient experienced cognitive impairment. Magnetic resonance imaging of the brain showed a high-intensity lesion in the right cerebral peduncle and internal capsule. A cerebrospinal fluid examination confirmed central nervous system (CNS) relapse of MEITL. After 3 cycles of MPV (methotrexate, procarbazine, vincristine) followed by whole-brain radiotherapy, her cognitive impairment improved. Due to disease progression, she died 6 months after CNS relapse. Given the CNS relapse after achieving a CR with GDP and CBT in this patient, CNS prophylaxis during first-line therapy may be beneficial in the treatment of MEITL.


Assuntos
Neoplasias Encefálicas/patologia , Transplante de Células-Tronco de Sangue do Cordão Umbilical , Neoplasias Intestinais/patologia , Linfoma de Células T/patologia , Recidiva Local de Neoplasia/patologia , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Encefálicas/etiologia , Feminino , Humanos , Neoplasias Intestinais/terapia , Linfoma de Células T/terapia , Recidiva Local de Neoplasia/etiologia
17.
Brain Behav ; 11(4): e02075, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33599392

RESUMO

OBJECTIVE: Our previous metabolomics study showed that the plasma nervonic acid levels were higher in patients with major depressive disorder (MDD) than those in healthy controls and patients with bipolar disorder (BD). To examine whether the nervonic acid levels differ in the central nervous system, we investigated the levels in the cerebrospinal fluid (CSF) of patients with MDD, BD, and healthy controls. METHODS: Nervonic acid levels in CSF were measured by gas chromatography time-of-flight mass spectrometry. The participants included 30 patients with MDD, 30 patients with BD, and 30 healthy controls. RESULTS: In contrast to our previous study, no significant differences were found in the nervonic acid level in the CSF among the patients with MDD, BD, and the healthy controls. Though no significant state-dependent changes were found among the three groups, we did observe a significant negative correlation between the nervonic acid levels and depressive symptoms in the depressive state of patients with MDD and BD (r = -0.38, p = .046). Further, a significant positive correlation was found between the nervonic acid levels and manic symptoms in the manic state of patients with BD (r = 0.79, p = .031). CONCLUSION: The nervonic acid levels in the CSF did not differ among the patients with MDD, BD, and the healthy controls; however, a significant negative correlation with depressive symptoms and a positive correlation with manic symptoms was observed. Thus, the nervonic acid levels in the CSF may be a candidate biomarker for mood symptoms.


Assuntos
Transtorno Depressivo Maior , Biomarcadores , Ácidos Graxos Monoinsaturados , Humanos , Projetos Piloto
18.
Int J Hematol ; 111(5): 628-633, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31721035

RESUMO

B1 cells, which are distinct from conventional B cells, are a rare B lymphocyte subpopulation that plays a pivotal role in innate immunity. Extensive previous studies have revealed the functions and ontogeny of murine B1 cells, but the properties of human B1 cells have just begun to be uncovered over the past decade. The phenotype of human B1 cells has recently been proposed, facilitating further studies. Here, we review the latest knowledge on human B1 cells, especially their ontogeny. A previous study using xenotransplantation models showed that human hematopoietic stem cells (HSCs) derived from cord blood or adult bone marrow can produce B1 cells in vivo. A recent study by our group reported that human B1 cells in peripheral blood are derived from adult HSCs and persist for approximately 3 years in situ. These findings suggest that adult human HSCs have the ability to produce B1 cells and contribute to maintenance of the adult B1 cell pool in peripheral blood. Further understanding of human B1 cell functions and ontogeny may elucidate the pathogenesis of B cell malignancies and autoimmune diseases.


Assuntos
Subpopulações de Linfócitos B/imunologia , Animais , Subpopulações de Linfócitos B/fisiologia , Células da Medula Óssea , Linfócitos T CD4-Positivos/imunologia , Sangue Fetal , Genes abl , Transplante de Células-Tronco Hematopoéticas , Hemoglobinúria Paroxística/imunologia , Xenoenxertos , Humanos , Imunidade Inata , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Camundongos , Fenótipo
19.
Artigo em Inglês | MEDLINE | ID: mdl-31428606

RESUMO

Poly(2-hydroxybutyrate) [P(2HB)] is an artificial polyhydroxyalkanoate (PHA) synthesized using engineered 2-hydroxyalkanoate-polymerizing PHA synthase. In the present study, the effect of temperature on P(2HB) synthesis was investigated. Recombinant Escherichia coli harboring PHA synthetic genes were cultivated with 2HB and 3-hydroxybutyrate (3HB) supplementation at varied temperatures ranging from 24 to 36°C for the synthesis of P(2HB) and natural PHA P(3HB), respectively. P(2HB) production and its molecular weight increased considerably at a threshold temperature of 32-34°C. The trend was not observed during the synthesis of P(3HB). Notably, the threshold temperature was close to the glass transition temperature (T g) of P(2HB) (30°C), while the T g of P(3HB) (4°C) was much lower than the cultivation temperature. The results suggest that thermal motion of the polymer chains influenced the production and molecular weight of the obtained polymer. According to the results, the production and molecular weight of PHA drastically changes at the threshold temperature, which is linked to the T g of the polymer. The hypothesis should be applicable to PHAs in general, and potentially explains the inability to biosynthesize high-molecular-weight polylactate homopolymer with a T g of 60°C.

20.
Am J Case Rep ; 20: 1022-1026, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31303639

RESUMO

BACKGROUND Massive tongue hemorrhage in patients with hemophilia is a medical emergency because it can lead to airway obstruction. However, managing bleeding in patients with inhibitors is more difficult than in patients without inhibitors. We report a case of life-threatening massive tongue and retropharyngeal hematoma in a patient with hemophilia A who had inhibitors. CASE REPORT The patient was a 71-year-old man with severe hemophilia A with high-responding inhibitors. He was admitted to our hospital with dysarthria and dysphagia secondary to a massive tongue hematoma. Although bypassing therapy was started immediately after admission, he rapidly developed an airway obstruction and cardiopulmonary arrest secondary to suffocation. Cardiopulmonary resuscitation and surgical cricothyrotomy were performed, which restored his pulse and breathing. On day 5 of hospitalization, he underwent tracheotomy under inhibitor-neutralizing therapy, and we began emicizumab on day 19 of hospitalization to prevent further bleeding events. He recovered and was transferred to another hospital for rehabilitation on day 64 of hospitalization. CONCLUSIONS Because tongue hematomas progress dramatically within a few days, prompt airway maintenance by tracheotomy under appropriate hemostatic therapy must be considered. Furthermore, emicizumab induction after primary hemostasis prevents further bleeding. We suggest that initiating emicizumab therapy is a good choice to prevent further bleeding after critical bleeding events if the patient has not received the drug previously.


Assuntos
Hematoma/etiologia , Hemofilia A/complicações , Hemofilia A/tratamento farmacológico , Hemorragia/etiologia , Doenças da Língua/etiologia , Idoso , Anticorpos Biespecíficos/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Fator VIIa/uso terapêutico , Humanos , Masculino , Proteínas Recombinantes/uso terapêutico , Espaço Retroperitoneal
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