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1.
Inorg Chem ; 56(11): 6094-6104, 2017 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-28260387

RESUMO

We describe a new strategy for triggering the photochemical release of caged carbon monoxide (CO) in aerobic media using long-wavelength visible and near-infrared (NIR) light. The dinuclear rhenium-manganese carbonyl complexes (CO)5ReMn(CO)3(L), where L = phenanthroline (1), bipyridine (2), biquinoline (3), or phenanthrolinecarboxaldehyde (4), each show a strong metal-metal-bond-to-ligand (σMM → πL*) charge-transfer absorption band at longer wavelengths. Photolysis with deep-red (1 and 2) or NIR (3 and 4) light leads to homolytic cleavage of the Re-Mn bonds to give mononuclear metal radicals. In the absence of trapping agents, these radicals primarily recombine to reform dinuclear complexes. In oxygenated media, however, the radicals react with dioxygen to form species much more labile toward CO release via secondary thermal and/or photochemical reactions. Conjugation of 4, with an amine-terminated poly(ethylene glycol) oligomer, gives a water-soluble derivative with similar photochemistry. In this context, we discuss the potential applications of these dinuclear complexes as visible/NIR-light-photoactivated CO-releasing moieties (photoCORMs).

3.
Int J Prosthodont ; 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37256258

RESUMO

PURPOSE: To evaluate the effect of immersion in water on deformation of maxillary denture bases created by computer-aided design and computer-aided manufactured (CAD-CAM), and heat-polymerized resin fabrication techniques under loading condition. MATERIALS AND METHODS: Two-millimeter thick denture bases were fabricated using four techniques: CAD-CAM milling (CCM) (Polywax; Yamahachi), 3D printing (3DP) (BV0005; NextDent), compression molding (CM) (Luciton 199), and injection molding (IM) (Ivobase) (n = 5 per group). Three static 49 N loads were applied perpendicular to each denture base, and the mean strain value (MSV) was recorded by strain gauges attached to the denture surface. The denture bases were stored at 37°C in distilled water for 14 and 28 days, and the MSVs under the same static load were recorded. RESULTS: The highest MSVs were observed at the posterior palatal seal, tuberosity, and labial notches of the dentures. The lowest MSVs were recorded for the CCM group, then the CM and IM. The highest MSVs were recorded for the 3DP group. No significant differences in regional MSVs (P > .05) were observed among the CCM, CM, and IM after 14 and 28 days in water. Large deviations in MSVs were recorded for the 3DP group across the measurement sites after water exposure (P < .05). CONCLUSIONS: CCM had the lowest denture deformation under static loading. After immersion in water, the deformation changes under static loading were stable for CCM, CM, and IM. However, variations among the materials used in 3DP group influenced the mechanical performance and presented larger deformations. Int J Prosthodont. 10.11607/ijp.8332.

4.
Turk J Gastroenterol ; 34(5): 483-489, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36789983

RESUMO

BACKGROUND: Idiopathic mesenteric phlebosclerosis is a rare condition with unclear pathogenesis. This study aimed to investigate the clinical features, diagnostic modalities, treatments, and outcomes of idiopathic mesenteric phlebosclerosis patients in Taiwan. METHODS: Idiopathic mesenteric phlebosclerosis patients diagnosed by the typical characteristic of tree-like mesenteric venous calcifications on plain abdominal radiography or computed tomography between January 1992 and July 2021 were retrospectively analyzed. RESULTS: Totally, 36 idiopathic mesenteric phlebosclerosis patients were enrolled (50% females; mean age, 61.6 years). Among the included patients, 26 (72.2%) and 10 (27.7%) were symptomatic and asymptomatic, respectively. Abdominal pain (61.1%) accounted for the majority of all symptoms, followed by fever, diarrhea, and bloody stools. Our results showed that 83.3% of patients had at least 1 risk factor, whereas 16.6% of patients had none. Moreover, among the included patients, 36.1%, 44.4%, 50.0%, 38.8%, and 8.3% had cardiovascular disease, chronic renal disease, cancer, chronic liver disease, and diabetes mellitus, respectively. Our findings showed 94.4% of patients were diagnosed via abdominal computed tomography and plain abdominal radiography, whereas 5.6% of patients were diagnosed via plain abdominal radiography. The ascending colon was the most commonly involved site (100%). Our findings showed that 91.6% of patients experienced good recovery after conservative treatment, except for the 3 who died of sepsis and respiratory failure. By contrast, 8.3% of idiopathic mesenteric phlebosclerosis patients underwent colectomy. The average follow-up duration was 62.5 months. CONCLUSIONS: Idiopathic mesenteric phlebosclerosis remains a rare disease in Taiwan. Plain abdominal radiography and computed tomography can be utilized for establishing a definite diagnosis. Conservative treatment is usually adequate for most patients, with surgical treatment only indicated for severe cases.


Assuntos
Calcinose , Colite Isquêmica , Feminino , Humanos , Pessoa de Meia-Idade , Masculino , Taiwan/epidemiologia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/efeitos adversos , Colite Isquêmica/diagnóstico , Calcinose/complicações , Calcinose/diagnóstico
5.
PLoS One ; 17(2): e0260018, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35113863

RESUMO

BACKGROUND: The variations in ABO blood groups are reported to be associated with multiple disorders, including ulcerative colitis (UC). We aimed to investigate the distribution of ABO blood groups in UC patients and explore its impact on disease severity. METHODS: We retrospectively collected 129 UC patients diagnosed at our hospital between January 2000 and November 2019. Clinical characteristics, ABO blood groups, and operation rates were analyzed. RESULTS: The mean diagnostic age of patients was 38.97 years. Males accounted for the majority of all patients (62.8%). Of 129 patients, 43 (33.3%) were blood type O, 41 (31.8%) were blood type A, 38 (29.5%) were blood type B, and 7 (5.4%) were blood type AB. Although our patients had higher ratio of blood type A comparing our general population, there was no statistically significant association of ABO blood types distribution between these two groups (p = 0.1906). In the subgroup analysis, there were no significant difference of disease locations and operation rates between different ABO blood groups. Furthermore, blood type A patients had higher serum hemoglobin (Hb) levels compared to blood type O patients (13.31 g/dL vs. 12.30 g/dL, p = 0.0347). Blood type A patients had lower serum erythrocyte sedimentation rate (ESR) levels compared to blood type O patients (12.46 mm/hour vs. 21.5 mm/hour, p = 0.0288). Blood type O had higher serum ESR levels compared to non-O groups (p = 0.0228). In the ABO blood groups and mean diagnostic age (≤ 40 years or > 40 years), there were no statistically significant difference between these two age groups, p = 0.5515. CONCLUSIONS: Our results showed ABO blood groups are not associated with UC in spite of a higher ratio of blood type A in our patients. Blood type O patients had higher serum ESR levels; however, blood type A patients had higher Hb levels.


Assuntos
Colite Ulcerativa
6.
JGH Open ; 6(1): 63-68, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35071790

RESUMO

BACKGROUND AND AIM: Meckel's diverticulum (MD) is a common congenital abnormality of the gastrointestinal (GI) tract. Although a few patients with MD present symptoms, preoperative diagnosis of MD is a clinical challenge because of its endoscopic inaccessibility. The aim of the present study was to investigate patients with MD diagnosed by double-balloon enteroscopy (DBE) in Taiwan. METHODS: We conducted a retrospective study in a tertiary referral center in middle Taiwan. The clinical characteristics, endoscopic features, histopathological findings, treatment methods, and outcomes of patients with MD diagnosed by DBE were analyzed. RESULTS: A total of 14 male patients with MD diagnosed by DBE were enrolled. The mean age of all patients was 32.3 years. GI bleeding (78.6%) accounted for the major indication of DBE, followed by abdominal pain and Crohn's disease follow-up. The mean distance between the ileocecal valve and MD was 68.9 cm. The average length of 12 patients with surgically resected MD was 5.2 cm. The diagnostic yields of the other modalities excepting DBE are as follows: capsule endoscopy, 50%; Meckel's scan, 11.1%; computed tomography, 16.7%; small bowel series, 0%; and angiography, 33.3%. MD presented as a large ostium in 13 patients (92.9%), a small ostium in 1 patient (7.1%), and bleeding signs in 10 patients (71.4%). Twelve patients (85.7%) underwent surgical treatment and 2 patients (14.3%) received conservative treatment. Heterotopic gastric tissue was identified in 4 patients (28.6%). CONCLUSION: The present study showed that DBE is a more powerful modality in detecting MD than the other conventional modalities in Taiwan.

7.
ACS Omega ; 4(5): 9181-9187, 2019 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-31460006

RESUMO

Devices consisting of polymer disks (PDs) of optically clear or translucent, medical-grade silicone loaded with a new hydrophobic, oxygen-stable, photoactivated nitric oxide-releasing moiety (photoNORM) are described. The photoNORM is the new O-nitrito chromium(III) complex trans-[Cr(PetA)(ONO)2](BF4) (PetA = 5,14-dimethyl-7,12-diphenyl-1,4,8,11-tetraaza-cyclotetradecane), of which the synthesis, X-ray crystal structure, and solution-phase photochemistry are described. Several different commercially available silicone polymers were tested with this photoNORM, and nitric oxide photouncaging with 451 nm light from these systems is compared. In addition, PDs were loaded with the photoNORM and neodymium-sensitized upconverting nanoparticles (Nd-UCNPs). The Nd-UCNPs absorb NIR light at ∼800 nm and activate NO release from the trans-[Cr(PetA)(ONO)2]+ cation. The use of such ensembles as implants provides a potential strategy for the in vivo uncaging of NO at physiological targets triggered by tissue-transmitting NIR excitation. Also reported are the X-ray crystal structures of cis- and trans-{Cr(PetA)Cl2]Cl.

8.
Chem Sci ; 9(15): 3729-3741, 2018 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-29780505

RESUMO

Nitric oxide (NO) holds great promise as a treatment for cancer hypoxia, if its concentration and localization can be precisely controlled. Here, we report a "Trojan Horse" strategy to provide the necessary spatial, temporal, and dosage control of such drug-delivery therapies at targeted tissues. Described is a unique package consisting of (1) a manganese-nitrosyl complex, which is a photoactivated NO-releasing moiety (photoNORM), plus Nd3+-doped upconverting nanoparticles (Nd-UCNPs) incorporated into (2) biodegradable polymer microparticles that are taken up by (3) bone-marrow derived murine macrophages. Both the photoNORM [Mn(NO)dpaqNO2 ]BPh4(dpaqNO2 = 2-[N,N-bis(pyridin-2-yl-methyl)]-amino-N'-5-nitro-quinolin-8-yl-acetamido) and the Nd-UCNPs are activated by tissue-penetrating near-infrared (NIR) light at ∼800 nm. Thus, simultaneous therapeutic NO delivery and photoluminescence (PL) imaging can be achieved with a NIR diode laser source. The loaded microparticles are non-toxic to their macrophage hosts in the absence of light. The microparticle-carrying macrophages deeply penetrate into NIH-3T3/4T1 tumor spheroid models, and when the infiltrated spheroids are irradiated with NIR light, NO is released in quantifiable amounts while emission from the Nd-UCNPs provides images of microparticle location. Furthermore, varying the intensity of the NIR excitation allows photochemical control over NO release. Low doses reduce levels of hypoxia inducible factor 1 alpha (HIF-1α) in the tumor cells, while high doses are cytotoxic. The use of macrophages to carry microparticles with a NIR photo-activated theranostic payload into a tumor overcomes challenges often faced with therapeutic administration of NO and offers the potential of multiple treatment strategies with a single system.

9.
Chem Commun (Camb) ; 51(11): 2072-5, 2015 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-25532627

RESUMO

A water-soluble nanocarrier for a photo-activated CO releasing moiety (photoCORM) that can be triggered with NIR excitation is described. This has an upconversion nanoparticle core encapsulated by an amphiphilic polymer imparting both water solubility and a hydrophobic interior containing the photoCORM trans-Mn(bpy)(PPh3)2(CO)2. Such an ensemble offers a unique strategy for CO delivery to biological targets.


Assuntos
Monóxido de Carbono/química , Portadores de Fármacos/química , Raios Infravermelhos , Nanoestruturas/química , Liberação Controlada de Fármacos , Interações Hidrofóbicas e Hidrofílicas , Modelos Moleculares , Conformação Molecular , Solubilidade , Água/química
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