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1.
Neuroophthalmology ; 48(3): 169-175, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38756339

RESUMEN

Meningeal carcinomatosis (MC) has an extremely poor prognosis and can present with various neurological symptoms. A 68-year-old man presented to our hospital with a 1 month history of headache and nausea followed by sudden decrease in vision in both eyes. Whilst being examined in the ophthalmology department he lost consciousness and had a generalised tonic clonic seizure. Accordingly, he was transferred to the Emergency Department. Head magnetic resonance imaging showed hydrocephalus. Abdominal contrast-enhanced computed tomography scanning reported changes suggestive of gastric carcinoma. Cerebrospinal fluid cytological examination showed numerous atypical cells, leading to the diagnosis of MC. An upper gastrointestinal endoscopy revealed an advanced gastric tumour. Systemic chemotherapy was initiated, however, he died within 16 days of admission. At autopsy, poorly differentiated adenocarcinoma was identified in the subarachnoid space, however it had not invaded the brain parenchyma or optic chiasm. This is the first report of loss of vision being the first presenting symptom of new-onset gastric carcinoma with MC. Although rare, MC should be suspected in cases where patients present with sudden loss of vision and symptoms of meningeal irritation, where there are no ophthalmological findings to explain the vision loss.

2.
Anticancer Res ; 44(4): 1727-1737, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38537993

RESUMEN

BACKGROUND/AIM: The survival and prognostic factors in patients with advanced hepatocellular carcinoma (HCC) who underwent surgical intervention after lenvatinib treatment is not well-understood. PATIENTS AND METHODS: Seventy-six patients with advanced HCC who had lenvatinib treatment were retrospectively analyzed. RESULTS: Of 70 patients who were treated with lenvatinib, 14 patients underwent surgical intervention after lenvatinib treatment for 4-28 weeks. Progression-free survival (PFS) was significantly longer in patients who underwent surgical intervention than in patients with non-surgical treatment (median, 8.6 vs. 5.1 months, p=0.019). Non-significantly longer overall survival (OS) was also observed in patients with surgical intervention compared to patients with non-surgical treatment (median, unreached vs. 21.0 months, p=0.206). In patients who underwent surgical intervention, two patients had a partial response, and 12 had stable disease according to RECIST ver. 1.1 criteria. The serum alpha-fetoprotein (AFP) level was significantly lower after lenvatinib treatment than before lenvatinib treatment (median, 19.2 vs. 196.5 ng/ml, p=0.0081). Eleven patients underwent curative surgery with a 14% major postoperative complication (Clavien-Dindo ≥IIIa) rate. Patients who exhibited decreases in AFP levels or maintained AFP levels within the normal range during lenvatinib treatment had significantly longer PFS (median, 8.6 vs. 3.0 months, p=0.0009) and OS (median, unreached vs. 12.4 months, p=0.012) compared to those with persistently elevated AFP levels beyond the normal range. CONCLUSION: Surgical intervention after lenvatinib treatment for advanced HCC was associated with longer PFS. Patients exhibiting decreased AFP levels or maintaining AFP levels within the normal limit may be suitable candidates for surgical intervention after lenvatinib treatment for advanced HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Compuestos de Fenilurea , Quinolinas , Humanos , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/cirugía , Estudios Retrospectivos , alfa-Fetoproteínas , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/cirugía
3.
Case Rep Oncol ; 16(1): 537-543, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37485012

RESUMEN

We report a 58-year-old male with a histopathologically proven grade 2 (G2) pancreatic neuroendocrine neoplasm and multiple abdominal node metastases by use of a laparoscopic pancreatic body and tail resection procedure, plus abdominal lymph node dissection. A primary pancreatic tail neuroendocrine tumor sized 20 × 25 mm was detected by contrast-enhanced computed tomography, somatostatin receptor scintigraphy (SRS), and fluorodeoxyglucose positron emission tomography (FDG-PET) examinations and pathologically diagnosed as a pancreatic neuroendocrine tumor (PNET, G2) based on positive immunostaining for somatostatin receptor (SSTR) type 2. Of three metastatic histopathological lymph nodes, two measured 18 × 21 and 10 × 12 mm, respectively, with whole strong SSTR immunostaining showing moderate uptake in SRS findings, whereas the other node, sized 8 × 10 mm, had strong SSTR immunostaining only in a small 6 × 6-mm-sized portion and showed no uptake in SRS findings, likely because of the limited spatial resolution of scintigraphy. On the other hand, only the largest node (18 × 21 mm) was visualized by FDG-PET. SRS may be useful for metastatic lymph node diagnosis based on SSTR immunostaining, though a disadvantage is the spatial resolution limitation.

4.
Surg Today ; 52(5): 822-831, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34708306

RESUMEN

PURPOSE: This study assessed the significance of measuring liver stiffness using virtual touch quantification before hepatectomy to predict posthepatectomy refractory ascites. METHODS: A total of 267 patients with hepatocellular carcinoma who underwent hepatectomy were prospectively analyzed. Liver stiffness was defined as the median value of the virtual touch quantification (Vs; m/s) by acoustic radio-force-impulse-based virtual touch. RESULTS: A multivariate analysis showed that Vs and the aspartate aminotransferase-to-platelet ratio index were independent risk factors for postoperative refractory ascites (odds ratio = 3.27 and 3.08, respectively). The cutoff value for Vs was 1.52 m/s (sensitivity: 59.5%, specificity: 88.6%) as determined by the analysis of the receiver-operating characteristic curve, and the area under the receiver-operating characteristic curve was 0.79. The cutoff value for the aspartate aminotransferase-to-platelet ratio was 0.952 (sensitivity: 65.5%, specificity: 82.9%), and the area under the receiver-operating characteristic curve was 0.75. CONCLUSIONS: Vs is an independent risk factor for refractory ascites after hepatectomy. The measurement of liver stiffness by virtual touch quantification before hepatectomy can help estimate the risk of postoperative refractory ascites. Nonsurgical treatments should be considered for the management of patients who are at high risk for refractory ascites.


Asunto(s)
Carcinoma Hepatocelular , Diagnóstico por Imagen de Elasticidad , Neoplasias Hepáticas , Ascitis/etiología , Aspartato Aminotransferasas , Carcinoma Hepatocelular/patología , Hepatectomía/efectos adversos , Humanos , Neoplasias Hepáticas/patología , Complicaciones Posoperatorias/diagnóstico por imagen , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía , Curva ROC
5.
Nihon Shokakibyo Gakkai Zasshi ; 118(6): 549-554, 2021.
Artículo en Japonés | MEDLINE | ID: mdl-34108354

RESUMEN

The Japanese guidelines for the treatment of gastric cancer recommend nivolumab as third-line chemotherapy for metastatic gastric adenocarcinoma. We report a case in which long-term control of metastatic gastric adenocarcinoma was achieved with nivolumab after pseudoprogression. A man in his late 70s with advanced HER2-negative gastric cancer and liver metastasis underwent total gastrectomy to control tumor bleeding. He then underwent chemotherapy with S-1 plus oxaliplatin, followed by S-1 alone. After metastases in the liver and para-aortic and hilar lymph nodes regrew, the patient received ramucirumab plus paclitaxel as second-line chemotherapy, followed by third-line therapy with nivolumab. After four cycles of nivolumab, these metastases showed progression;however, the treatment was continued because levels of CA19-9 were decreased, and performance status was good. After five more cycles of nivolumab, the liver metastasis shrank, and CA19-9 levels decreased;therefore, we confirmed pseudoprogression. The patient suffered no immune-related adverse events and survived for 50 months after gastrectomy with 34 cycles of nivolumab treatment. Thus, at the beginning of treatment with an immune checkpoint inhibitor, oncologists must consider the possibility of pseudoprogression in cases of tumor growth associated with decreasing tumor marker levels and good performance status.


Asunto(s)
Nivolumab , Neoplasias Gástricas , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Gastrectomía , Humanos , Ganglios Linfáticos , Masculino , Nivolumab/uso terapéutico , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/cirugía
6.
Transl Vis Sci Technol ; 8(6): 20, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31788349

RESUMEN

PURPOSE: We investigated whether daily consumption of Spirulina, an antioxidant generating cyanobacterial nutritional supplement, would suppress photostress-induced retinal damage and prevent vision loss in mice. METHODS: Six-week-old male BALB/cAJcl mice were allowed constant access to either a standard or Spirulina-supplemented diet (20% Spirulina) that included the antioxidants, ß-carotene and zeaxanthin, and proteins for 4 weeks. Following dark adaptation, mice were exposed to 3000-lux white light for 1 hour and returned to their cages. Visual function was analyzed by electroretinogram, and retinal histology by hematoxylin and eosin staining, terminal deoxynucleotidyl transferase-mediated, deoxyuridine triphosphate nick-end labeling (TUNEL) assay, and immunohistochemistry. Retinal expression of proteins, reactive oxygen species (ROS), and mRNAs were measured using immunoblot analysis, enzyme-linked immunosorbent assay (ELISA), 2',7'-dichlorofluorescein-diacetate, or ROS Brite 700 Dyes, and real-time reverse-transcription polymerase chain reaction, respectively. RESULTS: Light-induced visual function impairment was suppressed by constant Spirulina intake. Thinning of the photoreceptor layer and outer segments, photoreceptor cell death, decreased rhodopsin protein, and induction of glial fibrillary acidic protein were ameliorated in the Spirulina-intake group. Increased retinal ROS levels after light exposure were reduced by Spirulina supplementation. Light-induced superoxide dismutase 2 and heme oxygenase-1 mRNAs in the retina, and Nrf2 activation in the photoreceptor cells, were preserved with Spirulina supplementation, despite reduced ROS levels, suggesting two pathways for suppressing ROS, scavenging and induction of endogenous antioxidative enzymes. Light-induced MCP-1 retinal mRNA and proteins were also suppressed by Spirulina. CONCLUSIONS: Spirulina ingestion protected retinal photoreceptors from photostress in the retina. TRANSLATIONAL RELEVANCE: Spirulina has potential as a nutrient supplement to prevent vision loss related to oxidative damage in the future.

7.
PLoS One ; 12(6): e0178627, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28570634

RESUMEN

Excessive exposure to light promotes degenerative and blinding retinal diseases such as age-related macular degeneration and retinitis pigmentosa. However, the underlying mechanisms of photo-induced retinal degeneration are not fully understood, and a generalizable preventive intervention has not been proposed. Bilberry extract is an antioxidant-rich supplement that ameliorates ocular symptoms. However, its effects on photo-stressed retinas have not been clarified. In this study, we examined the neuroprotective effects of bilberry extract against photo-stress in murine retinas. Light-induced visual function impairment recorded by scotopic and phototopic electroretinograms showing respective rod and cone photoreceptor function was attenuated by oral administration of bilberry extract through a stomach tube in Balb/c mice (750 mg/kg body weight). Bilberry extract also suppressed photo-induced apoptosis in the photoreceptor cell layer and shortening of the outer segments of rod and cone photoreceptors. Levels of photo-induced reactive oxygen species (ROS), oxidative and endoplasmic reticulum (ER) stress markers, as measured by real-time reverse transcriptase polymerase chain reaction, were reduced by bilberry extract treatment. Reduction of ROS by N-acetyl-L-cysteine, a well-known antioxidant also suppressed ER stress. Immunohistochemical analysis of activating transcription factor 4 expression showed the presence of ER stress in the retina, and at least in part, in Müller glial cells. The photo-induced disruption of tight junctions in the retinal pigment epithelium was also attenuated by bilberry extract, repressing an oxidative stress marker, although ER stress markers were not repressed. Our results suggest that bilberry extract attenuates photo-induced apoptosis and visual dysfunction most likely, and at least in part, through ROS reduction, and subsequent ER stress attenuation in the retina. This study can help understand the mechanisms of photo-stress and contribute to developing a new, potentially useful therapeutic approach using bilberry extract for preventing retinal photo-damage.


Asunto(s)
Modelos Animales , Extractos Vegetales/farmacología , Retina/efectos de los fármacos , Estrés Fisiológico , Vaccinium myrtillus/química , Acetilcisteína/administración & dosificación , Animales , Antioxidantes/administración & dosificación , Antioxidantes/farmacología , Electrorretinografía , Estrés del Retículo Endoplásmico/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos BALB C , Extractos Vegetales/administración & dosificación , Especies Reactivas de Oxígeno/metabolismo , Retina/metabolismo , Retina/fisiopatología , Retina/efectos de la radiación , Epitelio Pigmentado de la Retina/efectos de los fármacos , Epitelio Pigmentado de la Retina/efectos de la radiación
8.
Beilstein J Nanotechnol ; 8: 784-788, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28487821

RESUMEN

Surface flattening techniques are extremely important for the development of future electrical and/or optical devices because carrier-scattering losses due to surface roughness severely limit the performance of nanoscale devices. To address the problem, we have developed a near-field etching technique that provides selective etching of surface protrusions, resulting in an atomically flat surface. To achieve finer control, we examine the importance of the wavelength of the near-field etching laser. Using light sources at wavelengths of 325 and 405 nm, which are beyond the absorption edge of the photoresist (310 nm), we compare the resulting cross-sectional etching volumes. The volumes were larger when 325 nm light was employed, i.e., closer to the absorption edge. Although 405 nm light did not cause structural change in the photoresist, a higher reduction of the surface roughness was observed as compared to the 325 nm light. These results indicate that even wavelengths above 325 nm can cause surface roughness improvements without notably changing the structure of the photoresist.

9.
PLoS One ; 11(1): e0146517, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26771918

RESUMEN

PURPOSE: The determination of the molecular mechanism underlying retinal pathogenesis and visual dysfunction during innate inflammation, and the treatment effect of rapamycin thereon. METHODS: The endotoxin-induced uveitis and retinitis mouse model was established by injecting lipopolysaccharide. The mice were subsequently treated with rapamycin, a mammalian target of rapamycin (mTOR) inhibitor. The rhodopsin mRNA and protein expression level in the retina and the photoreceptor outer segment (OS) length in immunohistochemical stainings were measured, and visual function was recorded by electroretinography. Inflammatory cytokines, their related molecules, mTOR, and LC3 levels were measured by real-time PCR and/or immunoblotting. Leukocyte adhesion during inflammation was analyzed using concanavalin A lectin. RESULTS: The post-transcriptional reduction in the visual pigment of rod photoreceptor cells, rhodopsin, OS shortening, and rod photoreceptor cell dysfunction during inflammation were suppressed by rapamycin. Activation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and induction of inflammatory cytokines, such as interleukin-6 (IL-6) and monocyte chemoattractant protein-1 (MCP-1), and the activation of the downstream signaling protein, signal transducer and activator of transcription 3 (STAT3), which reduces rhodopsin in the retina during inflammation, were attenuated by rapamycin. Increased leukocyte adhesion was also attenuated by rapamycin. Interestingly, although mTOR activation was observed after NF-κB activation, mTOR inhibition suppressed NF-κB activation at the early phase, indicating that the basal level of activated mTOR was sufficient to activate NF-κB in the retina. In addition, the inhibition of NF-κB suppressed mTOR activation, suggesting a positive feedback loop of mTOR and NF-κB during inflammation. The ratio of LC3II to LC3I, which reflects autophagy induction, was not changed by inflammation but was increased by rapamycin. CONCLUSIONS: Our results propose the potential use of rapamycin as a neuroprotective therapy to suppress local activated mTOR levels, related inflammatory molecules, and the subsequent visual dysfunction during retinal inflammation.


Asunto(s)
Inflamación/tratamiento farmacológico , FN-kappa B/metabolismo , Retina/efectos de los fármacos , Retina/inmunología , Retinitis/tratamiento farmacológico , Sirolimus/farmacología , Sirolimus/uso terapéutico , Animales , Masculino , Ratones , Ratones Endogámicos C57BL , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Retinitis/inmunología , Transducción de Señal , Uveítis/tratamiento farmacológico , Uveítis/inmunología
10.
BMC Ophthalmol ; 14: 114, 2014 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-25270019

RESUMEN

BACKGROUND: Macular hole results from a tractional force at the vitreo-retinal interface which is developed by modification and subsequent degeneration of the posterior precortical vitreous and the internal limiting membrane (ILM). Meanwhile, the wet type of age-related macular degeneration (AMD) is caused by the submacular formation of choroidal neovascularization (CNV). Although exudative changes derived from CNV may cause epiretinal membrane (ERM) formation, which can also cause tractional force at the vitreo-retinal interface, there have been few reports of AMD-associated macular hole development in which the full thickness of the retinal tissue is completely torn by the tractional force. Moreover, intraoperative finding of macular hole associated with AMD with a possible involvement of subretinal lesion has not been described. CASE PRESENTATION: A 78-year-old man diagnosed with wet AMD with subretinal fluid and mild cataract received 8 treatments with intravitreal pegaptanib. After AMD remission, he developed a secondary macular hole in the same eye. He underwent a pars plana vitrectomy that successfully closed the macular hole. Intraoperatively, it was found that the patient's vitreous was formed and that the ERM and ILM were adherent, suggesting the involvement of a tractional force at the vitreo-retinal interface due to an inflammatory reaction related to AMD and/or intravitreally injected chemical compounds, resulting in macular hole development. Changes in the condition of his AMD and the RPE were observed on a fluorescein angiogram (FA) and an indocyanine green angiogram (IA) that preceded macular hole development, suggesting that subretinal changes may also have been involved in the pathogenesis. CONCLUSION: These clinical data, including the intraoperative findings and the temporal changes in the angiograms, suggest that an inflammatory reaction at the vitreo-retinal interface and subretinal lesion related to AMD contribute to the macular hole development in AMD patients treated with intravitreal injection.


Asunto(s)
Angiografía con Fluoresceína , Perforaciones de la Retina/diagnóstico , Perforaciones de la Retina/cirugía , Vitrectomía , Degeneración Macular Húmeda/complicaciones , Anciano , Aptámeros de Nucleótidos/uso terapéutico , Membrana Basal/patología , Colorantes , Membrana Epirretinal/diagnóstico , Humanos , Verde de Indocianina , Periodo Intraoperatorio , Masculino , Perforaciones de la Retina/etiología , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Degeneración Macular Húmeda/tratamiento farmacológico
11.
Int Surg ; 99(5): 577-83, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25216424

RESUMEN

Abstract A 78-year-old man was admitted to our hospital with right upper abdominal pain and fever. His general condition was poor. The laboratory data showed severe inflammatory reactions. Computed tomography revealed an irregular tumor in the gallbladder. (18)F-fluorodeoxy-glucose positron emission tomography (FDG-PET) showed high uptake by the tumor, with diffuse uptake in the spine. Based on the elevated leukocyte count and FDG-PET findings, a granulocyte-colony stimulating factor (G-CSF)-producing tumor was diagnosed (G-CSF 120 pg/mL). We performed cholecystectomy with central bisegmentectomy of the liver, lymph node dissection and right hemicolectomy. Histologically, the tumor was an adenosquamous cell carcinoma of the gallbladder. Immunohistochemical staining of the tumor cells was positive for G-CSF. Postoperatively, the general condition of the patient was improved. The fever subsided, the leukocyte count and serum G-CSF level normalized, and FDG-PET showed no uptake in the spine postoperatively. The patient showed no signs of recurrence at 27 months after undergoing surgery. FDG-PET is a useful method for diagnosing G-CSF-producing gallbladder carcinoma. Aggressive curative resection for G-CSF-producing gallbladder carcinoma may improve patients' general condition and prognosis.


Asunto(s)
Carcinoma Adenoescamoso/metabolismo , Neoplasias de la Vesícula Biliar/metabolismo , Factor Estimulante de Colonias de Granulocitos/biosíntesis , Anciano , Carcinoma Adenoescamoso/diagnóstico , Carcinoma Adenoescamoso/patología , Carcinoma Adenoescamoso/cirugía , Colecistectomía , Fluorodesoxiglucosa F18 , Neoplasias de la Vesícula Biliar/diagnóstico , Neoplasias de la Vesícula Biliar/patología , Neoplasias de la Vesícula Biliar/cirugía , Humanos , Inmunohistoquímica , Masculino , Tomografía de Emisión de Positrones
12.
Hepatology ; 57(1): 362-72, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22936459

RESUMEN

UNLABELLED: Concanavalin A (Con A) treatment induces severe hepatitis in mice in a manner dependent on T cells, interferon (IFN)-gamma, and tumor necrosis factor (TNF). Treatment with the anticoagulant heparin protects against hepatitis, despite healthy production of IFN-γ and TNF. Here, we investigated molecular and cellular mechanisms for hypercoagulation-mediated hepatitis. After Con A challenge, liver of wild-type (WT) mice showed prompt induction of Ifnγ and Tnf, followed by messenger RNA expression of tissue factor (TF) and plasminogen activator inhibitor-1 (PAI-1), which initiate blood coagulation and inhibit clot lysis, respectively. Mice developed dense intrahepatic fibrin deposition and massive liver necrosis. In contrast, Ifnγ(-/-) mice and Ifnγ(-/-) Tnf(-/-) mice neither induced Pai1 or Tf nor developed hepatitis. In WT mice TF blockade with an anti-TF monoclonal antibody protected against Con A-induced hepatitis, whereas Pai1(-/-) mice were not protected. Both hepatic macrophages and sinusoidal endothelial cells (ECs) expressed Tf after Con A challenge. Macrophage-depleted WT mice reconstituted with hematopoietic cells, including macrophages deficient in signal transducer and activator of transcription-1 (STAT1) essential for IFN-γ signaling, exhibited substantial reduction of hepatic Tf and of liver injuries. This was also true for macrophage-depleted Stat1(-/-) mice reconstituted with WT macrophages. Exogenous IFN-γ and TNF rendered T-cell-null, Con A-resistant mice deficient in recombination-activating gene 2, highly susceptible to Con A-induced liver injury involving TF. CONCLUSIONS: Collectively, these results strongly suggest that proinflammatory signals elicited by IFN-γ, TNF, and Con A in both hepatic macrophages and sinusoidal ECs are necessary and sufficient for the development of hypercoagulation-mediated hepatitis.


Asunto(s)
Hepatitis Animal/etiología , Interferón gamma , Hígado/metabolismo , Trombofilia/complicaciones , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Concanavalina A , Células Endoteliales/metabolismo , Fibrina/metabolismo , Hepatitis Animal/metabolismo , Hepatitis Animal/patología , Interferón gamma/metabolismo , Hígado/inmunología , Hígado/patología , Macrófagos/metabolismo , Ratones , Ratones Noqueados , Mitógenos , Necrosis , Inhibidor 1 de Activador Plasminogénico/metabolismo , Factor de Transcripción STAT1/metabolismo , Transducción de Señal , Linfocitos T/fisiología , Trombofilia/inducido químicamente , Tromboplastina/metabolismo
13.
Photomed Laser Surg ; 29(5): 333-8, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21495857

RESUMEN

OBJECTIVE: Bleeding control is a major concern during dental surgery. A novel photocoagulation method using an irradiating blue-violet light emitting diode (LED) was investigated. BACKGROUND: Some dental light-curving units can emit blue-violet wavelengths around 380-515 nm with two peaks (410 nm and 470 nm). These wavelengths can cover the maximum absorption spectra of hemoglobin (430 nm). MATERIALS AND METHODS: Blue-violet LED 380-515 nm, 750 mW/cm(2), 10 sec (7.5 J/cm(2)) was used. Irradiation was performed for 10 sec or an additional 10 sec for 10 cases of tooth extraction at a distance of 1 cm from the socket. Bleeding was stopped by conventional roll pressure in another five cases as a control. Bleeding time for both procedures was measured. A Mann-Whitney U test was used for statistical analysis. In vitro transmission electron microscope (TEM) studies were performed to clarify the mechanism of hemostasis by blue-violet LED irradiation. RESULTS: Irradiation with the blue-violet LED yielded immediate hemostasis of the socket. Five cases showed coagulation within the first 10 sec, and another five cases required an additional 10 sec to fully control the bleeding. In contrast, the conventional method required 2-5 min (median 180 sec) to obtain hemostasis. The difference between the time required to stop the bleeding in the two methods was found to be statistically significant (p = 0.0014). A week later, the LED-irradiated sockets were healed uneventfully with epithelial covering. TEM showed the formation of a thin amorphous layer and an adjacent agglutination of platelets and other cellular elements under the layer at the interface of the irradiated blood. CONCLUSION: Blue-violet LED irradiation of bleeding sockets caused immediate clot formation and hemostasis. This procedure was safe and reliable and showed no adverse effects.


Asunto(s)
Hemorragia Bucal/prevención & control , Fototerapia , Hemorragia Posoperatoria/prevención & control , Extracción Dental/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Hemorragia Bucal/etiología , Hemorragia Posoperatoria/etiología , Alveolo Dental
14.
PLoS One ; 6(1): e16226, 2011 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-21283826

RESUMEN

RNase HI from the hyperthermophile Sulfolobus tokodaii (Sto-RNase HI) is stabilized by its C-terminal residues. In this work, the stabilization effect of the Sto-RNase HI C-terminal residues was investigated in detail by thermodynamic measurements of the stability of variants lacking the disulfide bond (C58/145A), or the six C-terminal residues (ΔC6) and by structural analysis of ΔC6. The results showed that the C-terminal does not affect overall structure and stabilization is caused by local interactions of the C-terminal, suggesting that the C-terminal residues could be used as a "stabilization tag." The Sto-RNase HI C-terminal residues (-IGCIILT) were introduced as a tag on three proteins. Each chimeric protein was more stable than its wild-type protein. These results suggested the possibility of a simple stabilization technique using a stabilization tag such as Sto-RNase HI C-terminal residues.


Asunto(s)
Proteínas Recombinantes de Fusión/química , Ribonucleasa H/química , Sulfolobus/enzimología , Secuencia de Aminoácidos , Variación Genética , Métodos , Estabilidad Proteica , Ribonucleasa H/genética , Termodinámica
15.
BMC Evol Biol ; 10: 207, 2010 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-20615256

RESUMEN

BACKGROUND: The unfolding speed of some hyperthermophilic proteins is dramatically lower than that of their mesostable homologs. Ribonuclease HII from the hyperthermophilic archaeon Thermococcus kodakaraensis (Tk-RNase HII) is stabilized by its remarkably slow unfolding rate, whereas RNase HI from the thermophilic bacterium Thermus thermophilus (Tt-RNase HI) unfolds rapidly, comparable with to that of RNase HI from Escherichia coli (Ec-RNase HI). RESULTS: To clarify whether the difference in the unfolding rate is due to differences in the types of RNase H or differences in proteins from archaea and bacteria, we examined the equilibrium stability and unfolding reaction of RNases HII from the hyperthermophilic bacteria Thermotoga maritima (Tm-RNase HII) and Aquifex aeolicus (Aa-RNase HII) and RNase HI from the hyperthermophilic archaeon Sulfolobus tokodaii (Sto-RNase HI). These proteins from hyperthermophiles are more stable than Ec-RNase HI over all the temperature ranges examined. The observed unfolding speeds of all hyperstable proteins at the different denaturant concentrations studied are much lower than those of Ec-RNase HI, which is in accordance with the familiar slow unfolding of hyperstable proteins. However, the unfolding rate constants of these RNases H in water are dispersed, and the unfolding rate constant of thermophilic archaeal proteins is lower than that of thermophilic bacterial proteins. CONCLUSIONS: These results suggest that the nature of slow unfolding of thermophilic proteins is determined by the evolutionary history of the organisms involved. The unfolding rate constants in water are related to the amount of buried hydrophobic residues in the tertiary structure.


Asunto(s)
Evolución Molecular , Pliegue de Proteína , Ribonucleasa H/metabolismo , Proteínas Arqueales/genética , Proteínas Arqueales/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Dicroismo Circular , Estabilidad Proteica , Estructura Terciaria de Proteína , Ribonucleasa H/genética , Sulfolobus/enzimología , Sulfolobus/genética , Temperatura , Termodinámica , Thermotoga maritima/enzimología , Thermotoga maritima/genética
16.
Chemistry ; 12(30): 7827-38, 2006 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-16838381

RESUMEN

Novel heterocyclic quinol-type fluorophores (4 a-c) and (5 a-c) that contain substituents (R = Me, Bu, Ph) with nonconjugated linkages to the chromophore skeleton have been synthesized and their photophysical properties have been investigated in solution and in the solid state. Considerable differences in the absorption and fluorescence spectra were observed between the two states. Quinols 4 a-c and 5 a-c exhibited almost the same absorption and fluorescence spectra in solution; however, their solid-state fluorescence excitation and emission spectra in the crystalline state were quite different. We performed X-ray crystallographic analyses to elucidate the dramatic effect of the substituents of the nonconjugated linkage on the solid-state fluorescence excitation and emission spectra. The relationships between the solid-state photophysical properties and the chemical and crystal structures of 4 a-c and 5 a-c are discussed on the basis of the X-ray crystal structures.

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