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2.
Angew Chem Int Ed Engl ; : e202304303, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37130008

RESUMO

One striking feature of enzyme is its controllable ability to trap substrates via synergistic or cooperative binding in the enzymatic pocket, which renders the shape-selectivity of product by the confined spatial environment. The success of shape-selective catalysis relies on the ability of enzyme to tune the thermodynamics and kinetics for chemical reactions. In emulation of enzyme's ability, we showcase herein a targeting strategy with the substrate being anchored on the internal pore wall of metal-organic frameworks (MOFs), taking full advantage of the sterically kinetic control to achieve shape-selectivity for the reactions. For this purpose, a series of binding site-accessible metal metalloporphyrin-frameworks (MMPFs) have been investigated to shed light on the nature of enzyme-mimic catalysis. They exhibit a different density of binding sites that are well arranged into the nanospace with corresponding distances of opposite binding sites. Such a structural specificity results in a facile switch in selectivity from an exclusive formation of the thermodynamically stable product to the kinetic product. Thus, the proposed targeting strategy, based on the combination of porous materials and binding events, paves a new way to develop highly efficient heterogeneous catalysts for shifting selectivity.

3.
J Am Chem Soc ; 145(6): 3491-3498, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36749207

RESUMO

Class Ic ribonucleotide reductases (RNRIc) and R2-like ligand-binding oxidases (R2lox) are known to contain heterobimetallic MnIIFeII cofactors. How these enzymes assemble MnIIFeII cofactors has been a long-standing puzzle due to the weaker binding affinity of MnII versus FeII. In addition, the heterobimetallic selectivity of RNRIc and R2lox has yet to be reproduced with coordination complexes, leading to the hypothesis that RNRIc and R2lox overcome the thermodynamic preference for coordination of FeII over MnII with their carefully constructed three-dimensional protein structures. Herein, we report the selective formation of a heterobimetallic MnIIFeII complex accomplished in the absence of a protein scaffold. Treatment of the ligand Py4DMcT (L) with equimolar amounts of FeII and MnII along with two equivalents of acetate (OAc) affords [LMnIIFeII (OAc)2(OTf)]+ (MnIIFeII) in 80% yield, while the diiron complex [LFeIIFeII(OAc)2(OTf)]+ (FeIIFeII) is produced in only 8% yield. The formation of MnIIFeII is favored regardless of the order of addition of FeII and MnII sources. X-ray diffraction (XRD) of single crystals of MnIIFeII reveals an unsymmetrically coordinated carboxylate ligand─a primary coordination sphere feature shared by both RNRIc and R2lox that differentiates the two metal binding sites. Anomalous XRD studies confirm that MnIIFeII exhibits the same site selectivity as R2lox and RNRIc, with the FeII (d6) center preferentially occupying the distorted octahedral site. We conclude that the successful assembly of MnIIFeII originates from (1) Fe-deficient conditions, (2) site differentiation, and (3) the inability of ligand L to house a dimanganese complex.


Assuntos
Ferro , Ribonucleotídeo Redutases , Ferro/química , Ligantes , Oxirredutases/metabolismo , Ribonucleotídeo Redutases/química , Compostos Ferrosos
4.
Angew Chem Int Ed Engl ; 62(14): e202301191, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-36705521

RESUMO

Synthesizing solids in molten fluxes enables the rapid diffusion of soluble species at temperatures lower than in solid-state reactions, leading to crystal formation of kinetically stable compounds. In this study, we demonstrate the effectiveness of mixed hydroxide and halide fluxes in synthesizing complex Sr/Ag/Se in mixed LiOH/LiCl. We have accessed a series of two-dimensional Sr(Ag1-x Lix )2 Se2 layered phases. With increased LiOH/LiCl ratio or reaction temperature, Li partially substituted Ag to form solid solutions of Sr(Ag1-x Lix )2 Se2 with x up to 0.45. In addition, a new type of intergrowth compound [Sr3 Se2 ][(Ag1-x Lix )2 Se2 ] was synthesized upon further reaction of Sr(Ag1-x Lix )2 Se2 with SrSe. Both Sr(Ag1-x Lix )2 Se2 and [Sr3 Se2 ][(Ag1-x Lix )2 Se2 ] exhibit a direct band gap, which increases with increasing Li substitution (x). Therefore, the band gap of Sr(Ag1-x Lix )2 Se2 can be precisely tuned via fine-tuning x that is controlled by only the flux ratio and temperature.

5.
Hepatobiliary Pancreat Dis Int ; 22(2): 147-153, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36690522

RESUMO

BACKGROUND: Open pancreaticoduodenectomy (OPD) with portal or superior mesenteric vein resection and reconstruction has been applied in pancreatic cancer patients with tumor infiltration or adherence. However, it is controversial whether laparoscopic pancreaticoduodenectomy (LPD) with major vascular resection and reconstruction is feasible. This study aimed to evaluate the safety and feasibility of LPD with major vascular resection compared with OPD with major vascular resection. METHODS: We reviewed data for all pancreatic cancer patients undergoing LPD or OPD with vascular resection at Department of Pancreatic Surgery, Fudan University Shanghai Cancer Center, between February 2018 and May 2022. We compared the preoperative, intraoperative, and postoperative clinicopathological data of the two groups to conduct a comprehensive evaluation of LPD with major vascular resection. RESULTS: A total of 63 patients underwent pancreaticoduodenectomy (PD) with portal or superior mesenteric vein resection and reconstruction, including 25 LPDs and 38 OPDs. The LPD group had less intraoperative blood loss (200 vs. 400 mL, P < 0.001), lower proportion of intraoperative blood transfusion (16.0% vs. 39.5%, P = 0.047), longer operation time (390 vs. 334 min, P = 0.004) and shorter postoperative hospital stay (11 vs. 14 days, P = 0.005). There was no perioperative death in all patients. There was no significant difference in the incidence of total postoperative complications, grade B/C postoperative pancreatic fistula, delayed gastric emptying and abdominal infection between the two groups. No postpancreatectomy hemorrhage nor bile leakage occurred during perioperative period. There was no significant difference in R0 resection rate and number of lymph nodes harvested between the two groups. Patency of reconstructed vessels in the two groups were 96.0% and 92.1%, respectively (P = 0.927). CONCLUSIONS: LPD with portal or superior mesenteric vein resection and reconstruction was safe, feasible and oncologically acceptable for selected patients with pancreatic cancer, and it can achieve similar or even better perioperative results compared to open approach.


Assuntos
Laparoscopia , Neoplasias Pancreáticas , Humanos , Pancreaticoduodenectomia/efeitos adversos , Pancreaticoduodenectomia/métodos , Veias Mesentéricas/diagnóstico por imagem , Veias Mesentéricas/cirurgia , Veias Mesentéricas/patologia , China , Neoplasias Pancreáticas/patologia , Veia Porta/cirurgia , Veia Porta/patologia , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Complicações Pós-Operatórias/cirurgia , Estudos Retrospectivos
6.
Nat Commun ; 14(1): 315, 2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36658155

RESUMO

N6-methyladenosine (m6A) has been demonstrated to regulate RNA metabolism and various biological processes, including gametogenesis and embryogenesis. However, the landscape and function of m6A at single cell resolution have not been extensively studied in mammalian oocytes or during pre-implantation. In this study, we developed a single-cell m6A sequencing (scm6A-seq) method to simultaneously profile the m6A methylome and transcriptome in single oocytes/blastomeres of cleavage-stage embryos. We found that m6A deficiency leads to aberrant RNA clearance and consequent low quality of Mettl3Gdf9 conditional knockout (cKO) oocytes. We further revealed that m6A regulates the translation and stability of modified RNAs in metaphase II (MII) oocytes and during oocyte-to-embryo transition, respectively. Moreover, we observed m6A-dependent asymmetries in the epi-transcriptome between the blastomeres of two-cell embryo. scm6A-seq thus allows in-depth investigation into m6A characteristics and functions, and the findings provide invaluable single-cell resolution resources for delineating the underlying mechanism for gametogenesis and early embryonic development.


Assuntos
Oócitos , Oogênese , Animais , Oócitos/metabolismo , Desenvolvimento Embrionário/genética , Transcriptoma/genética , RNA/metabolismo , Mamíferos/genética
7.
Nature ; 612(7938): 72-77, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36352229

RESUMO

Advancements in many modern technologies rely on the continuous need for materials discovery. However, the design of synthesis routes leading to new and targeted solid-state materials requires understanding of reactivity patterns1-3. Advances in synthesis science are necessary to increase efficiency and accelerate materials discovery4-10. We present a highly effective methodology for the rational discovery of materials using high-temperature solutions or fluxes having tunable solubility. This methodology facilitates product selection by projecting the free-energy landscape into real synthetic variables: temperature and flux ratio. We demonstrate the effectiveness of this technique by synthesizing compounds in the chalcogenide system of A(Ba)-Cu-Q(O) (Q = S or Se; A = Na, K or Rb) using mixed AOH/AX (A = Li, Na, K or Rb; X = Cl or I) fluxes. We present 30 unreported compounds or compositions, including more than ten unique structural types, by systematically varying the temperature and flux ratios without requiring changing the proportions of starting materials. Also, we found that the structural dimensionality of the compounds decreases with increasing reactant solubility and temperature. This methodology serves as an effective general strategy for the rational discovery of inorganic solids.

8.
Chem Commun (Camb) ; 58(88): 12305-12308, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36250295

RESUMO

The separation of xylene isomers still remains an industrially challenging task. Here, porous purine-based metal-organic frameworks (MOFs) have been synthesized and studied for their potential in xylene separations. In particular, Zn(purine)I showed excellent para-xylene/ortho-xylene separation capability with a diffusion selectivity of 6 and high equilibrium adsorption selectivity as indicated by coadsorption experiments. This high selectivity is attributed to the shape and size of the channel aperture within the rigid framework of Zn(purine)I.


Assuntos
Estruturas Metalorgânicas , Xilenos , Adsorção , Isomerismo , Purinas
9.
Chem Commun (Camb) ; 58(90): 12608-12611, 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36285715

RESUMO

We report the synthesis and oxygen-atom transfer (OAT) photochemistry of [Cu(tpa)BrO3]ClO4. In situ spectroscopy and in crystallo experiments indicate OAT proceeds from a Cu-O fragment generated by sequential Cu-O bond cleavage and OAT from BrOx to [Cu(tpa)]+. These results highlight synthetic opportunities in M-O photochemistry and demonstrate the utility of in crystallo experiments to evaluating photochemical reaction mechanisms.


Assuntos
Bromatos , Cobre , Cobre/química , Oxigênio/química , Fotoquímica
11.
Patient Saf Surg ; 16(1): 25, 2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35907905

RESUMO

INTRODUCTION: Partial fibular osteotomy has been recognized as a surgical alternative to treat medial compartment osteoarthritis of the knee. Related peroneal neuropathies are of concern among the relatively few complications after this procedure. In our clinical practice, the osteotomy level has therefore been modified to avoid the above defects. However, a rare case of vascular injury was encountered. Herein we describe an accidental anterior tibial artery pseudoaneurysm as a rare technical complication after this corrective osteotomy. CASE PRESENTATION: A 55-year-old male visited our emergency room, presenting a painful swelling over his right anterolateral shin along with surrounding ecchymosis. Thirteen days ago, he just underwent a corrective fibular osteotomy over his right painful varus knee at our institute, and was discharged after an uneventful postoperative stay. Urgent angiography revealed an out-pouching vascular lesion, pseudoaneurysm, involving his right anterior tibial artery. Prompt endovascular repair with stent insertion and balloon compression successfully stopped the persistent extravasation from the injured artery. Follow-up angiography as well as outpatient review confirmed the regression of this lesion and associated symptoms without sequelae. CONCLUSION: Although corrective fibular osteotomy is a simple surgical procedure, it is not free of complications. The suggested osteotomized level in the pertinent literature predisposes patients to certain neuromuscular deficits, which could be avoided by the modified level of osteotomy. However, our case highlights surgeons' familiarity with certain risky neurovascular structures around the osteotomy site and corresponding technical considerations. A recent surgical history along with alarming symptoms/signs should arouse clinical suspicion, aid in timely identification and make appropriate interventions for potential vascular complications.

12.
Medicine (Baltimore) ; 101(30): e29585, 2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35905203

RESUMO

Spontaneous osteonecrosis of the knee (SONK) causes knee pain and joint motion limitation. Ischemia or insufficiency fracture may be the cause, but no consensus has been developed. Proximal fibular osteotomy (PFO) has been reported to relieve pain from osteoarthritis through medial compartment decompression. We reviewed the effect of this procedure on medial compartment SONK patients and explored clinical and radiological results. Since January 2018 to January 2020, the data of 12 knees (8 right and 4 left) from 11 SONK patients (9 women and 2 men) who received PFO were analyzed. The average age was 61.5 years. The diagnosis of SONK was established through weight-bearing anterior-posterior radiographs or magnetic resonance imaging (MRI). Visual analog scale (VAS) scores, Oxford knee score (OKS), Femorotibial angle (FTA), medial joint space, and lateral joint space were documented preoperatively and at follow up visits. Outcome assessment for the clinical and radiographic data was reviewed at 12- and 24-month follow-up visits. The mean follow up period was 33 months. All patients were able to walk with or without cane assistance the day after surgery. Both VAS score and OKS (preoperative: 6.6 ± 0.9 and 24.7 ± 3.8, respectively) improved significantly at the 12-month follow-up, and to 24-month follow-up (3.6 ± 1.3 and 35.6 ± 4.5, respectively, P < .05). Medial joint space ratio increased from 0.36 to 0.50 (P < .05). Changes of FTA were insignificant at any point of follow up. Four patients underwent follow-up MRI, and a decrease in the osteonecrotic area was clearly observed in 2 patients. By achieving medial knee decompression, PFO allowed quick weight-bearing recovery, pain relief, and improvement in knee function in SONK patients.


Assuntos
Osteoartrite do Joelho , Osteonecrose , Osteotomia , Dor , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/complicações , Osteoartrite do Joelho/cirurgia , Osteonecrose/complicações , Osteonecrose/cirurgia , Osteotomia/métodos , Dor/etiologia , Dor/prevenção & controle , Estudos Retrospectivos , Resultado do Tratamento
13.
Inorg Chem ; 61(16): 6252-6262, 2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35416667

RESUMO

Mixed 3d metal oxides are some of the most promising water oxidation catalysts (WOCs), but it is very difficult to know the locations and percent occupancies of different 3d metals in these heterogeneous catalysts. Without such information, it is hard to quantify catalysis, stability, and other properties of the WOC as a function of the catalyst active site structure. This study combines the site selective synthesis of a homogeneous WOC with two adjacent 3d metals, [Co2Ni2(PW9O34)2]10- (Co2Ni2P2) as a tractable molecular model for CoNi oxide, with the use of multiwavelength synchrotron X-radiation anomalous dispersion scattering (synchrotron XRAS) that quantifies both the location and percent occupancy of Co (∼97% outer-central-belt positions only) and Ni (∼97% inner-central-belt positions only) in Co2Ni2P2. This mixed-3d-metal complex catalyzes water oxidation an order of magnitude faster than its isostructural analogue, [Co4(PW9O34)2]10- (Co4P2). Four independent and complementary lines of evidence confirm that Co2Ni2P2 and Co4P2 are the principal WOCs and that Co2+(aq) is not. Density functional theory (DFT) studies revealed that Co4P2 and Co2Ni2P2 have similar frontier orbitals, while stopped-flow kinetic studies and DFT calculations indicate that water oxidation by both complexes follows analogous multistep mechanisms, including likely Co-OOH formation, with the energetics of most steps being lower for Co2Ni2P2 than for Co4P2. Synchrotron XRAS should be generally applicable to active-site-structure-reactivity studies of multi-metal heterogeneous and homogeneous catalysts.

14.
J Integr Med ; 20(4): 329-337, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35487866

RESUMO

OBJECTIVE: This study evaluated the effectiveness of acupuncture treatment on postoperative pain in patients with degenerative lumbar spine disease, and explored the relationship between the postoperative analgesic effect of acupuncture and the sensation of acupuncture experienced by the patients. METHODS: This retrospective study analyzed the medical records of 97 patients who had undergone an operation by the same surgeon due to degenerative lumbar disease. These patients were divided into acupuncture group (n = 32), patient-controlled analgesia (PCA) group (n = 27), and oral analgesia group (n = 38) according to the different postoperative analgesic methods. During their hospitalization, patients completed daily evaluations of their pain using a visual analogue scale (VAS), and injection times of supplemental meperidine were recorded. Also, the Chinese version of the Massachusetts General Hospital Acupuncture Sensation Scale (C-MASS) was used in the acupuncture group. RESULTS: Each of the three treatment groups showed significant reductions in postoperative pain, as shown by reduced VAS scores. The acupuncture group, however, had less rebound pain (P < 0.05) than the other two groups. Both the acupuncture and PCA groups experienced acute analgesic effects that were superior to those in the oral analgesia group. In addition, the higher the C-MASS index on the second day after surgery, the lower the VAS score on the fourth day after surgery. There was also a significant difference in the "dull pain" in the acupuncture sensation. CONCLUSION: The results demonstrated that acupuncture was beneficial for postoperative pain and discomfort after simple surgery for degenerative spinal disease. It is worth noting that there was a disproportionate relevance between the patient's acupuncture sensation and the improvement of pain VAS score.


Assuntos
Terapia por Acupuntura , Analgesia , Pontos de Acupuntura , Analgesia/métodos , Analgésicos/uso terapêutico , Consenso , Humanos , Dor Pós-Operatória/tratamento farmacológico , Estudos Prospectivos , Estudos Retrospectivos , Sensação
15.
Protein Cell ; 13(12): 920-939, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35377064

RESUMO

SARS-CoV-2 infection causes complicated clinical manifestations with variable multi-organ injuries, however, the underlying mechanism, in particular immune responses in different organs, remains elusive. In this study, comprehensive transcriptomic alterations of 14 tissues from rhesus macaque infected with SARS-CoV-2 were analyzed. Compared to normal controls, SARS-CoV-2 infection resulted in dysregulation of genes involving diverse functions in various examined tissues/organs, with drastic transcriptomic changes in cerebral cortex and right ventricle. Intriguingly, cerebral cortex exhibited a hyperinflammatory state evidenced by significant upregulation of inflammation response-related genes. Meanwhile, expressions of coagulation, angiogenesis and fibrosis factors were also up-regulated in cerebral cortex. Based on our findings, neuropilin 1 (NRP1), a receptor of SARS-CoV-2, was significantly elevated in cerebral cortex post infection, accompanied by active immune response releasing inflammatory factors and signal transmission among tissues, which enhanced infection of the central nervous system (CNS) in a positive feedback way, leading to viral encephalitis. Overall, our study depicts a multi-tissue/organ transcriptomic landscapes of rhesus macaque with early infection of SARS-CoV-2, and provides important insights into the mechanistic basis for COVID-19-associated clinical complications.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , COVID-19/genética , Macaca mulatta , SARS-CoV-2/genética , Transcriptoma
16.
J Am Chem Soc ; 144(3): 1464-1472, 2022 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-35020391

RESUMO

Chlorine radicals readily activate C-H bonds, but the high reactivity of these intermediates precludes their use in regioselective C-H functionalization reactions. We demonstrate that the secondary coordination sphere of a metal complex can confine photoeliminated chlorine radicals and afford steric control over their reactivity. Specifically, a series of iron(III) chloride pyridinediimine complexes exhibit activity for photochemical C(sp3)-H chlorination and bromination with selectivity for primary and secondary C-H bonds, overriding thermodynamic preference for weaker tertiary C-H bonds. Transient absorption spectroscopy reveals that Cl· remains confined through formation of a Cl·|arene complex with aromatic groups on the pyridinediimine ligand. Furthermore, photocrystallography confirms that this selectivity arises from the generation of Cl· within the steric environment defined by the iron secondary coordination sphere.

17.
Inorg Chem ; 61(2): 950-967, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-34962391

RESUMO

The ruthenium nitrosyl moiety, {RuNO}6, is important as a potential releasing agent of nitric oxide and is of inherent interest in coordination chemistry. Typically, {RuNO}6 is found in mononuclear complexes. Herein we describe the synthesis and characterization of several multimetal cluster complexes that contain this unit. Specifically, the heterotrinuclear µ3-oxido clusters [Fe2RuCl4(µ3-O)(µ-OMe)(µ-pz)2(NO)(Hpz)2] (6) and [Fe2RuCl3(µ3-O)(µ-OMe)(µ-pz)3(MeOH)(NO)(Hpz)][Fe2RuCl3(µ3-O)(µ-OMe)(µ-pz)3(DMF)(NO)(Hpz)] (7·MeOH·2H2O) and the heterotetranuclear µ4-oxido complex [Ga3RuCl3(µ4-O)(µ-OMe)3(µ-pz)4(NO)] (8) were prepared from trans-[Ru(OH)(NO)(Hpz)4]Cl2 (5), which itself was prepared via acidic hydrolysis of the linear heterotrinuclear complex {[Ru(µ-OH)(µ-pz)2(pz)(NO)(Hpz)]2Mg} (4). Complex 4 was synthesized from the mononuclear Ru complexes (H2pz)[trans-RuCl4(Hpz)2] (1), trans-[RuCl2(Hpz)4]Cl (2), and trans-[RuCl2(Hpz)4] (3). The new compounds 4-8 were all characterized by elemental analysis, ESI mass spectrometry, IR, UV-vis, and 1H NMR spectroscopy, and single-crystal X-ray diffraction, with complexes 6 and 7 being characterized also by temperature-dependent magnetic susceptibility measurements and Mössbauer spectroscopy. Magnetometry indicated a strong antiferromagnetic interaction between paramagnetic centers in 6 and 7. The ability of 4 and 6-8 to form linkage isomers and release NO upon irradiation in the solid state was investigated by IR spectroscopy. A theoretical investigation of the electronic structure of 6 by DFT and ab initio CASSCF/NEVPT2 calculations indicated a redox-noninnocent behavior of the NO ancillary ligand in 6, which was also manifested in TD-DFT calculations of its electronic absorption spectrum. The electronic structure of 6 was also studied by an X-ray charge density analysis.

18.
Inorg Chem ; 61(1): 141-153, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34939800

RESUMO

We present the magnetic properties of a new family of S = 1 molecule-based magnets, NiF2(3,5-lut)4·2H2O and NiX2(3,5-lut)4, where X = HF2, Cl, Br, or I (lut = lutidine C7H9N). Upon creation of isolated Ni-X···X-Ni and Ni-F-H-F···F-H-F-Ni chains separated by bulky and nonbridging lutidine ligands, the effect that halogen substitution has on the magnetic properties of transition-metal-ion complexes can be investigated directly and in isolation from competing processes such as Jahn-Teller distortions. We find that substitution of the larger halide ions turns on increasingly strong antiferromagnetic interactions between adjacent Ni2+ ions via a novel through-space two-halide exchange. In this process, the X···X bond lengths in the Br and I materials are more than double the van der Waals radius of X yet can still mediate significant magnetic interactions. We also find that a simple model based on elongation/compression of the Ni2+ octahedra cannot explain the observed single-ion anisotropy in mixed-ligand compounds. We offer an alternative that takes into account the difference in the electronegativity of axial and equatorial ligands.

19.
Environ Sci Pollut Res Int ; 29(57): 85669-85675, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34669130

RESUMO

This study aimed to investigate the impact of weather conditions on the daily incidence of the COVID-19 pandemic in late spring 2021 in Taiwan, which is unlike the weather conditions of the COVID-19 outbreak in 2020. Meteorological parameters such as maximum daily temperature, relative humidity, and wind speed were included. The Spearman rank correlation test was used to evaluate the relationship between weather and daily domestic COVID-19 cases. The maximum daily temperature had a positively significant correlation with daily new COVID-19 cases within a 14-day lag period, while the relative humidity and wind speed has a fairly high correlation with the number of daily cases within a 13- and 14-day lag, respectively. In addition, the weather characteristics during this period were an increasingly high temperature, with steady high relative humidity and slightly decreasing wind speed. Our study revealed the weather conditions at the time of the domestic outbreak of COVID-19 in Taiwan in May 2021 and the possible association between weather factors and the COVID-19 pandemic. Further large-scale analysis of weather factors is essential for understanding the impact of weather on the spread of infectious diseases.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , Pandemias , SARS-CoV-2 , Taiwan/epidemiologia , Tempo (Meteorologia) , Umidade , Temperatura
20.
Acupunct Med ; 40(1): 68-77, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34553631

RESUMO

BACKGROUND: A hyperdynamic circulation and impaired vascular responsiveness to vasoconstrictors are observed in portal hypertension (PHT) rats. Inflammation is a major contributor to the hyperdynamic circulation state in murine models of PHT. Electroacupuncture (EA) may ameliorate the inflammatory response and limit arterial vasodilatation and portal pressure. This study investigated the possible mechanisms underlying putative hemodynamics effects of EA in normal and PHT rats. METHODS: PHT was induced by bile duct ligation (BDL) surgery over 4 weeks in rats. Sham-operated and BDL rats were treated with low-frequency EA (2 Hz) at ST36 10 min three times weekly for one or two consecutive weeks (for a total of 3 or 7 treatments, respectively). Serum tumor necrosis factor-α (TNF-α), nitrite/nitrate (NOx) and 6-keto-prostaglandin F1α (6-keto-PGF1α) were analyzed, and hemodynamic variation and contractile responses to phorbol-12,13-dibutyrate and phenylephrine in aortic and superior mesenteric arterial rings were recorded. Inducible (i) and endothelial (3) nitric oxide synthase (NOS), cyclooxygenase-1 (COX-1), and protein kinase C-α (PKC-α) levels were determined by Western blotting. RESULTS: EA significantly reduced portal pressure and serum TNF-α, NOx and 6-keto-PGF1α levels compared to the untreated BDL group, enhanced maximum contractile responses in the aorta, up-regulated PKC-α, and down-regulated iNOS and COX-1 levels. In addition, EA decreased the aortic angiogenesis signaling cascade, reflected by down-regulation of vascular endothelial growth factor (VEGF) abundance and transforming growth factor ß receptor (TGFßR)I/II expression, as assessed by immunostaining. CONCLUSION: EA attenuates TNF-α, NO and 6-keto-PGF1α overproduction, modulates the vascular levels of constitutive NOS and PKC-α, blunts the development of the angiogenesis cascade, and enhances vascular contractile force in PHT rats.


Assuntos
Eletroacupuntura , Hipertensão Portal , Animais , Ductos Biliares , Hipertensão Portal/terapia , Ligadura/efeitos adversos , Camundongos , Ratos , Ratos Sprague-Dawley , Fator A de Crescimento do Endotélio Vascular
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