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1.
Oxf Med Case Reports ; 2024(3): omae009, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38532755

RESUMO

An 80-year-old man presented in December with the main complaint of jaundice. Blood tests revealed hemolytic anemia and renal dysfunction. Positive syphilis serology results led to a diagnosis of untreated latent syphilis. A positive direct Coombs test led to a diagnosis of autoimmune hemolytic anemia (AIHA). Antibiotics were started for the syphilis, with improvement in the anemia and renal dysfunction observed. However, paroxysmal intravascular hemolysis occurred after his discharge. Based on a positive Donath-Landsteiner (D-L) test, paroxysmal cold hemoglobinuria (PCH) diagnosis was made. The hemolytic anemia improved after further treatment for syphilis, and further avoiding exposure to cold.

2.
Molecules ; 29(2)2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38257237

RESUMO

An unusual series of germylenes and stannylenes stabilized by new tetradentate bis(amidine) ligands RNC(R')N-linker-NC(R')NR with a rigid naphthalene backbone has been prepared by protonolysis reaction of Lappert's metallylenes [M(HMDS)2] (M = Ge or Sn). Germylenes and stannylenes were fully characterized by NMR spectroscopy and X-ray diffraction analysis. DFT calculations have been performed to clarify the structural and electronic properties associated with tetradentate bis(amidine) ligands. Stannylene L1Sn shows reactivity through oxidation, oxidative addition, and transmetalation reactions, affording the corresponding gallium and aluminum derivatives.

3.
Science ; 381(6661): 1011-1014, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37651508

RESUMO

A long-standing problem associated with silicone synthesis is contamination of the polymer products with 10 to 15% cyclic oligosiloxanes that results from backbiting reactions at the polymer chain ends. This process, in competition with chain propagation through ring-opening polymerization (ROP) of cyclic monomers, was thought to be unavoidable and routinely leads to a thermodynamically controlled reaction mixture (polymer/cyclic oligosiloxanes = 85/15). Here, we report that simple alcohol coordination to the anionic chain ends prevents the backbiting process and that a well-designed phosphonium cation acts as a self-quenching system in response to loss of coordinating alcohols to stop the reaction before the backbiting process begins. The combination of both effects allows a thermodynamically controlled ROP of the eight-membered siloxane ring D4 without producing undesirable cyclic oligosiloxanes.

4.
Adv Biol (Weinh) ; 7(12): e2300136, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37424388

RESUMO

Osteocytes have recently been identified as a new regulator of bone remodeling, but the detailed mechanism of their differentiation from osteoblasts remains unclear. The purpose of this study is to identify cell cycle regulators involved in the differentiation of osteoblasts into osteocytes and determine their physiological significance. The study uses IDG-SW3 cells as a model for the differentiation from osteoblasts to osteocytes. Among the major cyclin-dependent kinases (Cdks), Cdk1 is most abundantly expressed in IDG-SW3 cells, and its expression is down-regulated during differentiation into osteocytes. Inhibition of CDK1 activity reduces IDG-SW3 cell proliferation and differentiation into osteocytes. Osteocyte and Osteoblast-specific Cdk1 knockout in mice (Dmp1-Cdk1KO ) results in trabecular bone loss. Pthlh expression increases during differentiation, but inhibiting CDK1 activity reduces Pthlh expression. Parathyroid hormone-related protein concentration is reduced in the bone marrow of Dmp1-Cdk1KO mice. Four weeks of Parathyroid hormone administration partially recovers the trabecular bone loss in Dmp1-Cdk1KO mice. These results demonstrate that Cdk1 plays an essential role in the differentiation from osteoblast to osteocyte and the acquisition and maintenance of bone mass. The findings contribute to a better understanding of the mechanisms of bone mass regulation and can help develop efficient therapeutic strategies for osteoporosis treatment.


Assuntos
Osteoblastos , Osteócitos , Animais , Camundongos , Diferenciação Celular/genética , Proliferação de Células , Osteoblastos/metabolismo , Osteócitos/metabolismo , Hormônio Paratireóideo/farmacologia , Hormônio Paratireóideo/metabolismo
5.
Molecules ; 28(8)2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37110528

RESUMO

The present work focuses on the reactivity of S,S-bis-ylide 2, which presents a strong nucleophilic character, as evidenced by reactions with methyl iodide and CO2, affording C-methylated salts 3 and betaine 4, respectively. The derivatization of betaine 4 affords the corresponding ester derivative 6, which is fully characterized by using NMR spectroscopy and X-ray diffraction analysis. Furthermore, an original reaction with phosphenium ions leads to the formation of a transient push-pull phosphino(sulfonio)carbene 8, which rearranges to give stabilized sulfonium ylide derivative 7.

6.
Inorg Chem ; 62(16): 6488-6498, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37043365

RESUMO

A base-stabilized C-phosphonio-Si-amino-silyne 3 was synthesized, using an original method, through a coupling reaction between two Lewis-base-stabilized low-valent species: a silyliumylidene ion 1 and a P,S-bis-ylide 2 [C(0)-complex]. This new isolable cationic silyne 3 displays remarkably high stability at room temperature [t1/2 = 7 days in tetrahydrofuran (THF)] and a unique silyne reactivity thanks to the effect of phosphonio substituent.

7.
Dalton Trans ; 52(10): 3052-3058, 2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36779626

RESUMO

Novel norbornene-based imine-stabilized silylium ions 2 have been synthesized via the simple reaction of sulfide-stabilized silylium ion 1 with carbonyl derivatives. Those silylium ions were fully characterized in solution and in the solid state by NMR spectroscopy and X-ray diffraction analysis as well as DFT calculations. Unlike the previously reported phosphine-stabilized silylium ion VI, behaving as a Lewis pair, calculations show that 2 have a strong Lewis acid character. Indeed, imine-stabilized silylium ions 2 are able to activate Si-H bonds and catalyzed the hydrosilylation of carbonyl derivatives under mild conditions.

8.
Spine J ; 23(6): 799-804, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36774998

RESUMO

BACKGROUND CONTEXT: Lumbar spinal canal stenosis caused by degenerative lumbar spondylolisthesis is one of the most common indications for spinal surgery. However, the factors that influence its long-term (>10 years) outcomes remain unknown. DESIGN: This is a post-hoc analysis of a prospective randomized study. PURPOSE: This study aimed to determine factors that influence the long-term outcomes of instrumentation surgery for lumbar spinal canal stenosis due to degenerative lumbar spondylolisthesis. PATIENT SAMPLE: Patients aged ≤75 years with single L4/5 level lumbar canal stenosis caused by degenerative lumbar spondylolisthesis prospectively underwent instrumentation surgery at two hospitals between May 1, 2003, and April 30, 2012; the final follow-up examination was on May 20, 2021. OUTCOME MEASURES: The following data were collected: modified Japanese Orthopedic Association (JOA) score, JOA score recovery rate, visual analog scale (VAS) score for lower back and leg pain, and scores from eight short-form 36 (SF-36) subscales preoperatively and at the final follow-up examination. METHODS: Spearman's correlation analysis and univariate and multivariate regression analyses were used to examine preoperative factors that affect the JOA score recovery rate in patients who underwent instrumentation surgery for lumbar spinal canal stenosis at the L4/5 level due to degenerative lumbar spondylolisthesis. RESULTS: A total of 42 patients who underwent instrumentation surgery for degenerative lumbar spondylolisthesis and had a long-term follow-up period were included. Of these, 25 and 17 underwent posterolateral fusion and Graf stabilization, respectively. The mean postoperative follow-up duration was 12.5 years. Spearman's correlation analysis revealed that the long-term recovery rate was correlated with the preoperative VAS score for low back pain. In the univariate regression analysis, sex, preoperative VAS score for low back pain, and the SF-36 general health score were significantly associated with the long-term recovery rate. Meanwhile, the multiple stepwise regression analysis identified the preoperative VAS score for low back pain as an independent predictor of the long-term recovery rate. CONCLUSIONS: This study identified the preoperative VAS score for low back pain as an independent predictor of the long-term recovery rate following instrumentation surgery for degenerative lumbar spondylolisthesis. Therefore, when performing posterolateral fusion or Graf stabilization for degenerative lumbar spondylolisthesis, attention should be paid to the intensity of preoperative low back pain and considerations should be given to whether these procedures can improve the patient's symptoms in the long term.


Assuntos
Dor Lombar , Fusão Vertebral , Estenose Espinal , Espondilolistese , Humanos , Espondilolistese/complicações , Espondilolistese/cirurgia , Estudos Prospectivos , Dor Lombar/cirurgia , Dor Lombar/complicações , Constrição Patológica/complicações , Fusão Vertebral/métodos , Estenose Espinal/cirurgia , Estenose Espinal/complicações , Vértebras Lombares/cirurgia , Resultado do Tratamento , Estudos Retrospectivos
9.
Sci Rep ; 13(1): 939, 2023 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-36653400

RESUMO

In general, it is known that extreme climatic conditions such as El Niño and positive Indian Ocean Dipole (IOD+) cause prolonged drought in Indonesia's tropical peatlands so that groundwater levels (GWL) drop and peat is prone to fire. However, 27 years of GWL measurements in Central Kalimantan peat forests show the opposite condition, where the lowest GWL occurs several weeks before El Niño and after IOD+ reaches its peaks. We show that the dropped sea surface temperature anomaly induced by anomalously easterly winds along the southern Java-Sumatra occurs several weeks before the GWL drop to the lowest value. Local rainfall decreased, and GWL dropped sharply by 1.0 to 1.5 m, during the super El Niño events in 1997/98 and 2015, as well as remarkable events of IOD+ in 2019. It is suggested that the tropical peatland ecohydrological system (represented by the GWL), El Niño Southern Oscillation (ENSO), and IOD+ are teleconnected. Hence, monitoring GWL variability of peatland over the IMC is a possibility an alert for extreme climate events associated with El Niño and/or moderate IOD+.


Assuntos
El Niño Oscilação Sul , Água Subterrânea , Indonésia , Estações do Ano , Oceano Índico , Solo
10.
Angew Chem Int Ed Engl ; 62(4): e202215394, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36445806

RESUMO

A phosphine-stabilized silacyclopropyl cation 2 has been synthesized and fully characterized. Of particular interest, 2 reversibly isomerizes into the corresponding seven-membered cyclic (alkyl)(amino)silylene 3 at room temperature via a formal migratory ethylene insertion into the Si-P bond. Although silylene 3 has not been spectroscopically detected, its transient formation has been evidenced by the isolation of the corresponding disilene dimer 5 as well as by trapping reactions.

11.
Spine J ; 23(3): 425-432, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36400395

RESUMO

BACKGROUND CONTEXT: Although osteoporotic vertebral fractures (OVFs) are the most common type of osteoporotic fracture, few reports have closely investigated the factors contributing to the quality of life (QOL) in the chronic phase after thoracolumbar OVFs using detailed radiographic evaluation. PURPOSE: This study aimed to identify factors associated with the QOL in the chronic phase after thoracolumbar OVF. DESIGN: Post hoc analysis of a prospective randomized study. PATIENT SAMPLE: Participants included 195 patients with fresh thoracolumbar OVF managed conservatively with a brace who were available for radiographic analysis 48 weeks after injury. OUTCOME MEASURES: The degree of QOL impairment at 48 weeks after thoracolumbar OVF was assessed using the Japanese three-level version of the EuroQol five-dimensional questionnaire (EQ-5D) score. METHODS: Univariate and multivariate regression analyses were used to evaluate the relationships between the QOL and radiographic factors. RESULTS: The univariate analysis showed that age, analgesic use, T10/L5 Cobb angle on magnetic resonance imaging (MRI), subsequent vertebral fracture, and nonunion were significantly associated with the EQ-5D score at 48 weeks after thoracolumbar OVF. The multiple regression analysis showed that nonunion, analgesic use, subsequent vertebral fracture, and sacral slope on MRI were independently associated with the EQ-5D score at 48 weeks after thoracolumbar OVF. Receiver operating characteristic analysis for the deterioration of QOL showed that the cutoff value for sacral slope on MRI was 35 degrees. CONCLUSIONS: This study demonstrated that nonunion, subsequent vertebral fracture, and lower sacral slope were independently associated with poorer QOL in the chronic phase of thoracolumbar OVF managed conservatively with a brace. Therefore, improving or preventing these factors in patients with thoracolumbar OVF in the chronic phase may improve the QOL of the affected patients.


Assuntos
Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Humanos , Fraturas por Osteoporose/diagnóstico por imagem , Fraturas por Osteoporose/terapia , Fraturas por Osteoporose/complicações , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/terapia , Fraturas da Coluna Vertebral/complicações , Qualidade de Vida , Estudos Prospectivos , Analgésicos
12.
Am J Ophthalmol Case Rep ; 29: 101774, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36544753

RESUMO

Purpose: We describe the cases of two patients for whom we performed an epiretinal proliferation (EP) embedding technique combined with internal limiting membrane (ILM) flap inversion for a full-thickness macular hole (FTMH) with EP. Observations: Patient 1 was a 69-year-old Japanese man with decreased vision in his left eye (20/40). He underwent pars plana vitrectomy (PPV) twice for rhegmatogenous retinal detachment and intraocular lens (IOL) dislocation in his left eye. B-scan optical coherence tomography (OCT) imaging revealed FTMH and EP on the surface of a macular hole (MH). We performed a vitrectomy, EP embedding, and ILM inversion (fill). Patient 2 was a 73-year-old Japanese man with decreased vision in his right eye (20/32). He underwent PPV for vitreous hemorrhage and proliferative diabetic retinopathy in his right eye. B-scan OCT imaging revealed FTMH and EP on the surface of an MH. We performed a vitrectomy, EP embedding, and ILM inversion (cover). Six months post-surgery, the FTMH in both patients had closed completely, and each patient's foveal contour and visual acuity (20/20) had improved. Conclusions and importance: EP embedding combined with ILM flap inversion may be effective for treating secondary MHs with EP.

13.
Gan To Kagaku Ryoho ; 50(13): 1665-1667, 2023 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-38303376

RESUMO

A 51-year-old male presented with swelling on the left side of his neck. A diagnosis of thoracic esophageal cancer(Lt type 5a, squamous cell carcinoma, T3N4[16LN]M1[skin, bone, retroperitoneum, lung], cStage Ⅳb)was made, and treatment with a combination of 5-FU plus CDDP and pembrolizumab was initiated. After the 1st round of chemotherapy, there was an increase in metastases in the left cervical lymph node and skin, along with the development of back pain because of an L3 lumbar spine metastasis. Palliative radiotherapy(Σ24 Gy/6 Fr)was administered for all lesions. Subsequently, pembrolizumab was administered for the persistent decline in white blood cell and neutrophil counts. After 6 courses of pembrolizumab, computed tomography(CT)revealed an absence of lesions. Positron emission tomography/CT demonstrated no significant accumulation, prompting a diagnosis of complete response(CR). The patient is currently under pembrolizumab therapy and continues to remain in a state of CR.


Assuntos
Anticorpos Monoclonais Humanizados , Cisplatino , Neoplasias Esofágicas , Masculino , Humanos , Pessoa de Meia-Idade , Fluoruracila , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/patologia
14.
Bone Rep ; 17: 101635, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36389625

RESUMO

Objectives: As romosozumab has both bone anabolic and antiresorptive effects, it is not clear which patient groups are more likely to have decreased calcium concentrations when treated with romosozumab. The aim of this study was to investigate the impact of romosozumab treatment on serum calcium concentration in patients with osteoporosis with a high risk of fractures and identify factors that might be associated with, or even predict, a fluctuation in calcium concentration upon romosozumab administration. Materials and methods: In total, 47 patients were included in this retrospective study. We performed a Wilcoxon signed-rank test to identify differences in the calcium concentration before and 1 month after romosozumab initiation. Associations between baseline variables and changes in serum calcium concentration were investigated with a multiple-linear regression model using a forward-backward stepwise procedure. Results: Romosozumab administration reduced the serum calcium concentration by an average of 3.1 % after 1 month. No patient complained of symptoms of hypocalcemia during the first month after treatment. Univariate regression analysis showed that age and calcium concentration were significantly associated with the decrease in serum calcium concentrations by romosozumab administration. In addition, stepwise regression analysis identified age and calcium concentrations as independent factors associated with the decrease in calcium concentration by romosozumab. Conclusion: Romosozumab administration caused a modest but significant decrease in serum calcium concentration. Older age and higher baseline calcium concentrations were associated with a greater decrease in calcium concentrations by romosozumab administration. Although the likelihood of severe hypocalcemia from romosozumab administration may be low, physicians prescribing romosozumab to patients with osteoporosis should be aware of the symptoms of hypocalcemia and promptly evaluate calcium levels if patients complain of these symptoms.

15.
Chemistry ; 28(70): e202202037, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36074891

RESUMO

Several base-stabilized silyliumylidene ions (2 and 3) with different ligands were synthesized. Their behaviour appeared strongly dependent on the nature of ligand. Indeed, in contrast to the poorly reactive silyliumylidene ions 3 c,d stabilized by strongly donating ligands (DMAP, NHC), the silylene- and sulfide-supported one (2-H and 3 a) exhibits higher reactivity toward various small molecules. Furthermore, their capability to successively activate multiple small molecules was clearly demonstrated by processes involving successive reactions with silane/formamide, CO2 and H2 . Moreover, HBPin adduct of 3 a (8-C) catalyzes the hydroboration of pyridine. Of particular interest, silylene-supported silyliumylidene complex 2-H is one of the rare species able to activate two H2 molecules.

16.
Inorg Chem ; 61(40): 16156-16162, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36174242

RESUMO

Phosphine-stabilized Pb(II) cations, generated by chloride abstraction from chloroplumbylene 1, readily react with Lewis bases (L) such as phosphines and amines to give the corresponding donor-acceptor complexes 3. These complexes 3 react with phenylacetlylene via alkyne insertion into the Pb-L bond to afford the corresponding vinylplumbylenes 4. Of particular interest, the stable complex 4-HNiPr2 (with a secondary amine) can be used as a hydroamination catalyst of phenylacetylene.

17.
JBMR Plus ; 6(7): e10637, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35866147

RESUMO

Excluding clinical trials, there is limited evidence on the effect of 12 months of romosozumab treatment on bone mineral density (BMD) increase in real-world clinical practice because its use has only been approved recently. Thus, this study aimed to investigate the real-world effect of 12 months of romosozumab treatment on BMD increase and identify factors that predict the rate of BMD increase after 12 months of romosozumab treatment. We retrospectively investigated 106 patients who completed a 12-month romosozumab treatment for osteoporosis with a high risk of fractures at four hospitals from March 2020 to March 2022. The univariate and multiple regression analyses were performed to analyze the concurrent effects of various factors on the BMD increase after the 12-month romosozumab treatment. After 1 year of treatment, the lumbar spine BMD increased by 14.6%, and femoral neck BMD increased by 5.1%. Univariate regression analysis found that male sex, high tartrate-resistant acid phosphatase 5b (TRACP-5b) value before romosozumab administration, absence of osteoporosis medications before romosozumab administration, and low baseline lumbar spine BMD were associated with the extent of lumbar spine BMD increase. Moreover, stepwise multiple regression analysis found that the TRACP-5b value before romosozumab administration was a significant predictor of the rate of lumbar spine BMD increase after 1 year of romosozumab administration. In conclusion, our results demonstrated the effectiveness of the 12-month romosozumab treatment for osteoporosis with a high risk of fractures and the TRACP-5b value before romosozumab administration was a significant predictor of the rate of lumbar spine BMD increase after 1 year of romosozumab administration. Our findings could help establish more efficient treatment strategies for patients with osteoporosis at a high risk of fracture. © 2022 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

18.
Angew Chem Int Ed Engl ; 61(37): e202208202, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-35880424

RESUMO

The synthesis of a silyliumylidene cation complex 2 stabilized by a Ni0 -based donating ligand is reported. Experimental and theoretical studies demonstrate that the highly electrophilic SiII center is stabilized by a dative Ni→Si σ-interaction and π-donations from the amino- and Ni-moieties. Due to the energetically close frontier orbitals localized on the Si and Ni atoms, complex 2 presents a competitive reactivity at Si and Ni sites.

19.
Exp Mol Med ; 54(6): 753-764, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35668101

RESUMO

Differentiation of mesenchymal stem cells (MSCs) into osteoblasts is a critical process for proper skeletal development and acquisition/maintenance of bone mass. However, since this regulatory mechanism has not yet been fully elucidated, the treatment of severe osteoporosis and fractures is a challenge. Here, through a comprehensive analysis of gene expression during the differentiation of MSCs into osteoblasts, we show that the forkhead transcription factor Foxf2 is a crucial regulator of this process. Foxf2 expression transiently increased during MSC osteoblastic differentiation. Overexpression of Foxf2 in MSCs inhibited osteoblastic differentiation, and conversely, knockdown of Foxf2 expression promoted this process. Osteoprogenitor-specific Foxf2 knockout mice developed a high bone mass phenotype due to increased bone formation. RNA-seq analysis and molecular experiments revealed that Foxf2 regulation of bone formation is mediated by Wnt2b. Knockdown of Foxf2 in mouse femurs enhanced bone regeneration in vivo. FOXF2 expression was correlated with hip bone mineral density in postmenopausal women with low bone mass. Finally, inhibition of FOXF2 promoted osteoblastic differentiation of human MSCs. This study uncovers a critical role of Foxf2 in the differentiation of MSCs into osteoblasts and provides insight into the pathogenesis associated with bone-related diseases such as osteoporosis and nonunion after fracture.


Assuntos
Osteoporose , Via de Sinalização Wnt , Animais , Diferenciação Celular/genética , Feminino , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Glicoproteínas/metabolismo , Camundongos , Camundongos Knockout , Osteoblastos/metabolismo , Osteogênese/genética , Osteoporose/genética , Proteínas Wnt/metabolismo , beta Catenina/genética , beta Catenina/metabolismo
20.
Angew Chem Int Ed Engl ; 61(29): e202201932, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35510398

RESUMO

A donor-stabilized silylene 4 featuring a Ni0 -based donating ligand was synthesized. Complex 4 exhibits a pyramidalized and nucleophilic SiII center and shows a peculiar behavior due to the cooperative reactivity of Si and Ni centers. Calculations indicate that the orientation of Ni-ligands with respect to the silylene moiety is crucial in determining the role of the Ni-fragment (Lewis acid or Lewis base) towards silylene. Indeed, a simple 90° rotation of the Si-Ni bond, reverses the role of Ni, and transforms a classical silylene→Ni0 complex into an unprecedented Ni0 →silylene complex.

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