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1.
Phys Rev Lett ; 127(3): 031102, 2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34328784

RESUMO

We report observations of gamma-ray emissions with energies in the 100-TeV energy region from the Cygnus region in our Galaxy. Two sources are significantly detected in the directions of the Cygnus OB1 and OB2 associations. Based on their positional coincidences, we associate one with a pulsar PSR J2032+4127 and the other mainly with a pulsar wind nebula PWN G75.2+0.1, with the pulsar moving away from its original birthplace situated around the centroid of the observed gamma-ray emission. This work would stimulate further studies of particle acceleration mechanisms at these gamma-ray sources.

2.
Phys Rev Lett ; 126(14): 141101, 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33891464

RESUMO

We report, for the first time, the long-awaited detection of diffuse gamma rays with energies between 100 TeV and 1 PeV in the Galactic disk. Particularly, all gamma rays above 398 TeV are observed apart from known TeV gamma-ray sources and compatible with expectations from the hadronic emission scenario in which gamma rays originate from the decay of π^{0}'s produced through the interaction of protons with the interstellar medium in the Galaxy. This is strong evidence that cosmic rays are accelerated beyond PeV energies in our Galaxy and spread over the Galactic disk.

3.
Phys Rev Lett ; 123(5): 051101, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31491288

RESUMO

We report on the highest energy photons from the Crab Nebula observed by the Tibet air shower array with the underground water-Cherenkov-type muon detector array. Based on the criterion of a muon number measured in an air shower, we successfully suppress 99.92% of the cosmic-ray background events with energies E>100 TeV. As a result, we observed 24 photonlike events with E>100 TeV against 5.5 background events, which corresponds to a 5.6σ statistical significance. This is the first detection of photons with E>100 TeV from an astrophysical source.

4.
Phys Rev Lett ; 120(3): 031101, 2018 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-29400499

RESUMO

We analyze the Sun's shadow observed with the Tibet-III air shower array and find that the shadow's center deviates northward (southward) from the optical solar disk center in the "away" ("toward") interplanetary magnetic field (IMF) sector. By comparing with numerical simulations based on the solar magnetic field model, we find that the average IMF strength in the away (toward) sector is 1.54±0.21_{stat}±0.20_{syst} (1.62±0.15_{stat}±0.22_{syst}) times larger than the model prediction. These demonstrate that the observed Sun's shadow is a useful tool for the quantitative evaluation of the average solar magnetic field.

5.
Curr Oncol ; 21(3): e394-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24940098

RESUMO

BACKGROUND: Patients with alpha-fetoprotein (afp)-producing gastric cancer have a high incidence of liver metastasis and poor prognosis. There is some controversy about clinical manifestations in these patients. METHODS: Our study enrolled patients who, before surgery, had gastric cancer with serum afp exceeding 20 ng/mL [afp>20 (n = 58)] and with serum afp 20 ng/mL or less [afp≤20 (n = 1236)]. Clinical manifestations were compared between the groups. RESULTS: Early gastric cancer was more frequent (30.1% vs. 4%) and advanced gastric cancer was less frequent (69.9% vs. 96%) in the afp≤20 group than the afp>20 group (p < 0.001). Liver and lymph node metastasis occurred less frequently in the afp≤20 group (4.4% vs. 27.6%, p < 0.001, and 60.7% vs. 91.4%, p < 0.001, respectively). The 1-, 3-, 5-, and 10-year survival rates of afp≤20 patients were 75.2%, 53.4%, 45.8%, and 34.6% respectively. The 1-, 3-, 5-, and 10-year survival rates of patients with afp greater than 20 ng/mL, but 300 ng/mL or less, were 46.7%, 28.9%, 17.8%, and 13.3% respectively. The 1-, 3-, and 5-year survival rates of patients with serum afp greater than 300 ng/mL were 15.4%, 7.7%, and 0% respectively. The independent predictors for survival time were afp concentration, age, peritoneal seeding, liver metastasis, lymph node metastasis, vascular invasion, TNM stage, curative surgery, serosal invasion, and Lauren classification. CONCLUSIONS: Patients with high serum afp had a high frequency of liver and lymph node metastasis and very poor prognosis. More aggressive management with multimodal therapy (for example, chemotherapy, radiotherapy) might be needed when treating such patients.

6.
Phys Rev Lett ; 111(1): 011101, 2013 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-24027782

RESUMO

We report on a clear solar-cycle variation of the Sun's shadow in the 10 TeV cosmic-ray flux observed by the Tibet air shower array during a full solar cycle from 1996 to 2009. In order to clarify the physical implications of the observed solar cycle variation, we develop numerical simulations of the Sun's shadow, using the potential field source surface model and the current sheet source surface (CSSS) model for the coronal magnetic field. We find that the intensity deficit in the simulated Sun's shadow is very sensitive to the coronal magnetic field structure, and the observed variation of the Sun's shadow is better reproduced by the CSSS model. This is the first successful attempt to evaluate the coronal magnetic field models by using the Sun's shadow observed in the TeV cosmic-ray flux.

7.
Curr Oncol ; 27(3): e259-e264, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32669931

RESUMO

Background: Gastric stump ("remnant") cancer is the development of a malignancy related to previous gastric surgery. Prognosis in gastric stump cancer, compared with that in primary gastric cancer, is still controversial. Methods: From January 1988 to December 2012 at a single medical centre in Taiwan, 105 patients with gastric stump cancer, including 85 with previous peptic ulcer disease and 20 with previous gastric cancer, were analyzed for clinicopathologic characteristics and overall survival (os). Results: The 5-year os rates for patients with gastric stump cancer and with primary gastric cancer were 51.2% and 54.5% respectively (p = 0.035). Analysis of clinicopathologic characteristics indicated that, compared with patients having primary gastric cancer, those with gastric stump cancer had more lymph node metastasis (p < 0.001) and had been diagnosed at a more advanced stage (p = 0.047). Multivariate analysis with os as an endpoint showed that age [p = 0.015; hazard ratio (hr): 2.300; 95% confidence interval (ci): 1.173 to 4.509], tumour size (p = 0.037; hr: 1.700; 95% ci: 1.031 to 2.801), stromal reaction (p = 0.021; hr: 1.802; 95% ci: 1.094 to 2.969), and pathologic N category (p = 0.001; hr: 1.449; 95% ci: 1.161 to 1.807) were independent predictors in gastric stump cancer. The os rates for patients with gastric stump cancer who previously had gastric cancer or peptic ulcer disease were 72.9% and 50.0% respectively (p = 0.019). The Borrmann classification was more superficial (p = 0.005), lymph node metastases were fewer (p = 0.004), and staging was less advanced (p = 0.025) in patients with gastric stump cancer who previously had gastric cancer than in their counterparts who previously had peptic ulcer disease. Conclusions: Survival is poorer in patients with gastric stump cancer who previously had peptic ulcer disease than in those who previously had primary gastric cancer. Patients with gastric stump cancer who previously had gastric cancer and could receive curative gastrectomy tended to have a better prognosis because of a more superficial Borrmann classification. Regular follow-up in patients who have undergone gastric surgery is recommended for the early detection of gastric stump cancer.


Assuntos
Coto Gástrico/fisiopatologia , Neoplasias Gástricas/complicações , Neoplasias Gástricas/cirurgia , Idoso , Feminino , Humanos , Masculino , Prognóstico , Estudos Retrospectivos , Neoplasias Gástricas/mortalidade , Análise de Sobrevida
8.
Artigo em Zh | MEDLINE | ID: mdl-31914292

RESUMO

Objective:To analyze the relationship between ABO blood groups and otoacoustic emissions in full-term newborns, including the occurrence of SOAE and the amplitudes of DPOAE. Method:A total of eighty normal hearing female neonates were included in the study, with equal number of participants in each of the ABO blood group. Measurements of SOAE and DPOAE were collected from both ears of all participants. Result:The blood group O subjects showed significantly fewer SOAE occurrences and lower DPOAE amplitudes at 793 Hz, 1 257 Hz and 1 587 Hz than subjects with other three blood groups both in the left and right ears. Conclusion:The full-term neonates with blood group O have lower SOAE occurrence than other three blood group individual. The blood group O individuals have the lowest amplitude at 793 Hz, 1 257 Hz and 1 587 Hz of both ears.


Assuntos
Antígenos de Grupos Sanguíneos , Emissões Otoacústicas Espontâneas , Feminino , Audição , Humanos , Recém-Nascido
9.
Eur J Surg Oncol ; 33(5): 556-60, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17329063

RESUMO

AIMS: Pyloric stenosis usually presents with symptoms, and this may lead patients to consult their physician. We evaluate whether distal gastric cancer patients with pyloric stenosis had a better outcome than those without. METHODS: A total of 551 distal gastric cancer patients who received curative subtotal gastrectomy between January 1988 and December 2003 at Taipei Veterans General Hospital were analyzed. Among them, 174 patients were sorted into the pyloric stenosis group according to obstructive symptoms. Their clinicopathological features, survival and prognostic factors were evaluated. RESULTS: The 5-year overall and disease-free survival rate of distal third gastric adenocarcinoma for the pyloric stenosis group was significantly lower than those without pyloric stenosis. Multivariate analysis revealed the pyloric stenosis group had deeper cancer invasion (relative to pT1, RR of pT2 3.1, p=0.009; pT3 6.1, p<0.001; pT4 16.5, p<0.001), and more lymph node metastasis (RR 3.6; p=0.001). The pyloric stenosis group had a tendency to lymph node metastasis toward the hepatoduodenal ligament, but this did not reach statistical difference. However, the pyloric stenosis group had significantly higher lymph node metastasis in the retropancreatic region (5.17% vs. 0.53%; p=0.001). CONCLUSIONS: Distal gastric cancers with pyloric stenosis have worse biological behavior than those without, and consequently have a poor outcome.


Assuntos
Adenocarcinoma/diagnóstico , Adenocarcinoma/cirurgia , Estenose Pilórica/diagnóstico , Neoplasias Gástricas/diagnóstico , Idoso , Intervalo Livre de Doença , Feminino , Gastrectomia , Humanos , Metástase Linfática , Masculino , Prognóstico , Taxa de Sobrevida
10.
Eur J Surg Oncol ; 31(2): 153-7, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15698731

RESUMO

AIMS: We evaluate the influency stage migration in a randomised trial comparing D1 (N 1 lymphadenectomy) and D3 (N 1, 2 and 3 lymphadenectomy) dissections. METHODS: Two hundred and thirteen curatively resected patients were analysed, with this TNM data. RESULTS: After applying D3 patients' data according to simulated D1 staging, D3 resections were associated with up-staging to N2-3 levels in 8% of patients according to the N stage. The likelihood of N-status migration increased with increasing depth of invasion into the gastric wall. The increases in the calculated survival rate after stage migration on known 5-year survival rates were: 2% in stage IB, 1% in stage II, 4% in stage IIIA, and 1% in stage IIIB. CONCLUSIONS: Stage migration secondary to meticulous lymph node dissection affects stage-specific survival rates. True therapeutic survival benefit of D3 resection can only be assessed in this context.


Assuntos
Gastrectomia , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Humanos , Metástase Linfática , Estadiamento de Neoplasias , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/mortalidade , Neoplasias Gástricas/cirurgia , Análise de Sobrevida , Resultado do Tratamento
11.
Clin Cancer Res ; 5(7): 1745-51, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10430078

RESUMO

Protein tyrosine kinases (PTKs) are a major class of proto-oncogenes that are involved in tumor progression. The purpose of this study was to establish a comprehensive PTK expression profile in gastric cancers, with the objective of identifying possible biomarkers for gastric cancer progression. We have designed degenerate primers according to the consensus catalytic motifs to amplify PTK molecules from gastric cancers by reverse transcriptase-PCR methods. The PTK expression profile was established by sequencing analysis of the cloned PCR products. We have identified 17 PTKs from a gastric adenocarcinoma. Two receptor PTKs, tie-1 and axl, were selected for in situ immunohistochemistry studies because of their higher expression level and their described roles in adhesion, invasion, and angiogenesis. Among the 97 gastric adenocarcinoma tissues examined, we observed positive immunohistochemical staining of tie-1 PTK in 69 and positive staining of axl kinase in 71 tissues. Statistical analysis with clinicopathological features indicates that tie-1 kinase expression is inversely correlated with patients' survival, whereas axl fails to show similar clinical significance. Our results illustrate the utility of tyrosine kinase gene family profiling in human gastric cancers and show that tie-1 tyrosine kinase may serve as a novel independent prognostic marker for gastric adenocarcinoma patients.


Assuntos
Adenocarcinoma/química , Biomarcadores Tumorais/análise , Receptores Proteína Tirosina Quinases/análise , Receptores de Superfície Celular/análise , Neoplasias Gástricas/química , Adenocarcinoma/enzimologia , Adenocarcinoma/mortalidade , Idoso , Sequência de Aminoácidos , Humanos , Masculino , Dados de Sequência Molecular , Proteínas Oncogênicas/metabolismo , Prognóstico , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas , Receptores Proteína Tirosina Quinases/metabolismo , Receptor de TIE-1 , Receptores de TIE , Homologia de Sequência de Aminoácidos , Neoplasias Gástricas/enzimologia , Neoplasias Gástricas/mortalidade , Análise de Sobrevida , Receptor Tirosina Quinase Axl
12.
Eur Rev Med Pharmacol Sci ; 19(19): 3688-92, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26502859

RESUMO

OBJECTIVE: This study aimed to assess the benefits and risks of conscious sedation with midazolam and dezocine in diagnostic flexible bronchoscopy (FB). PATIENTS AND METHODS: This prospective case control study enrolled 40 non-sedated and 40 sedated subjects who underwent diagnostic FB. All received the standard upper airway preparation, while sedated subjects received midazolam and dezocine for conscious sedation. Subject discomforts during FB were assessed using the verbal analogue score (VAS, 0-10 scale). Willingness to return was assessed as five scales to monitor subject's satisfaction level. Safety profiles throughout the procedures were also assessed. RESULTS: Anterograde amnesia existed in 75.0% sedated subjects. Compared to non-sedated subjects, sedated ones expressed less discomfort, with lower VAS scores regarding scope insertion (4 [0-10] vs. 0 [0-4], p < 0.001), cough (5.5 [0-10] vs. 0 [0-4], p < 0.001), dyspnea (3.5 [0-10] vs. 0 [0-4], p<0.001), pain (3 [0-10] vs. 0 [0-5], p < 0.001), and global tolerance of the procedures (5.5 [1-10] vs. 0 [0-5], p < 0.001). More sedated subjects expressed willingness to return (90.0% vs. 30.0%, p < 0.001). Sedated subjects had no more hypoxemic episodes during the procedure (7.5% vs. 5.0%, p > 0.99), which were all transient and not life-threatening. CONCLUSIONS: Conscious sedation with midazolam and dezocine reduces discomforts, improves satisfaction level, and carries no significantly risks in subjects undergoing diagnostic FB.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Broncoscopia/métodos , Sedação Consciente/métodos , Hipnóticos e Sedativos/uso terapêutico , Midazolam/uso terapêutico , Tetra-Hidronaftalenos/uso terapêutico , Adulto , Idoso , Compostos Bicíclicos Heterocíclicos com Pontes/administração & dosagem , Estudos de Casos e Controles , Feminino , Humanos , Hipnóticos e Sedativos/administração & dosagem , Masculino , Midazolam/administração & dosagem , Pessoa de Meia-Idade , Estudos Prospectivos , Tetra-Hidronaftalenos/administração & dosagem
13.
J Appl Physiol (1985) ; 70(2): 554-60, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2022546

RESUMO

We examined the influence of a strenuous exercise regimen on tibial and metatarsal bones to show not only how the geometric, histological, and mechanical properties of immature bone respond to strenuous exercise but also how long bones within the same limb may respond differentially to exercise. Female Sprague-Dawley rats (8 wk old) were divided randomly into two groups: a sedentary control (n = 15) and an exercised group (n = 15). The exercise intensity was 80-90% of maximum oxygen capacity 5 days/wk for 10 wk. Mechanical properties of tibia and second metatarsus (MT) were determined with three-point bending, and contralateral bones were used for geometric and histological analyses. Length and middiaphyseal cross-sectional geometry of the exercised tibiae were significantly less than controls, but material properties were not different. The exercised tibiae had significantly lower structural properties (e.g., loads at the proportional limit and maximum and energy at failure load). The middiaphyseal dorsal cortex of exercised MT was significantly thicker than controls, but tensile stress at the proportional limit and elastic modulus of exercised MT were significantly less than controls. The average number of osteons and osteocytes per unit area of the tibial middiaphysis was significantly greater in the exercised group--especially in lateral and posterior cortices. The number of osteons and osteocytes per unit area in the MT, however, was significantly less in the exercised group. The differential effects of strenuous exercise on tibia and MT suggest that local loading and bone-specific responses have important roles in modulating the response of immature bone to strenuous exercise.


Assuntos
Osso e Ossos/fisiologia , Esforço Físico/fisiologia , Adaptação Fisiológica , Animais , Fenômenos Biomecânicos , Osso e Ossos/anatomia & histologia , Extremidades , Feminino , Osteoclastos/citologia , Osteócitos/citologia , Ratos , Ratos Endogâmicos
14.
Urology ; 46(4): 545-9, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7571226

RESUMO

OBJECTIVES: Our previous study revealed a decreased blood flow in varicocele-bearing testicles. For further understanding of the possible mechanism of varicocele-induced infertility, we investigated the changes in energy metabolism in varicocele-bearing testicles. METHODS: Partial ligation of the left renal vein was performed in 40 Wistar rats to induce dilation of the internal spermatic vein, and sham operations were performed in 20 other age-matched Wistar rats serving as controls. Orchiectomy was done at 1, 2, 4, and 6 months after induction of varicocele (or sham operation) in both groups. The histologic changes in the testicles were evaluated under the light microscope. The concentration of adenine nucleotides was determined by high-performance liquid chromatography, and various enzyme activities of mitochondria were determined by a spectrophotometer. RESULTS: Histologic studies of varicocele-bearing testicles showed a lower Johnsen score (8.5 +/- 0.7 versus 9.3 +/- 0.5) and a decreased mean testicular tubular diameter (280.0 +/- 3.2 versus 295.0 +/- 1.4 microns) compared with the testicles in the sham-operated group. The energy charge decreased from 0.71 +/- 0.04, 0.70 +/- 0.03, 0.69 +/- 0.06, and 0.64 +/- 0.03 to 0.62 +/- 0.08, 0.59 +/- 0.05, 0.58 +/- 0.05, and 0.56 +/- 0.02 at 1, 2, 4, and 6 months, respectively. The reduced nicotinamide-adenine dinucleotide-cytochrome c reductase activities were decreased from 136.6 +/- 4.9, 127.3 +/- 10.7, 121.6 +/- 7.8, and 118.9 +/- 8.5 to 96.3 +/- 13.9, 95.6 +/- 27.8, 88.3 +/- 13.8, and 80.4 +/- 8.7 nmol/min/mg of protein, respectively; the succinate-cytochrome c reductase activities were decreased from 50.4 +/- 2.7, 49.0 +/- 4.7, 49.6 +/- 7.1, and 42.6 +/- 1.6 to 40.3 +/- 7.3, 41.0 +/- 11.5, 40.2 +/- 5.7, and 32.0 +/- 1.3 nmol/min/mg of protein, respectively; and the cytochrome c oxidase activities were decreased from 361.2 +/- 23.4, 350.3 +/- 25.5, 223.5 +/- 12.9, and 194.1 +/- 18.3 to 253.7 +/- 32.9, 256.4 +/- 38.8, 178.2 +/- 15.7, and 147.1 +/- 17.2 nmol/min/mg of protein at 1, 2, 4, and 6 months, respectively. CONCLUSIONS: We thus suggest that defective energy metabolism plays an important role in the impairment of spermatogenesis of varicocele-bearing testicles.


Assuntos
Mitocôndrias/metabolismo , Fosforilação Oxidativa , Testículo/metabolismo , Varicocele/metabolismo , Animais , Masculino , Ratos , Ratos Wistar
15.
Oncol Rep ; 5(4): 817-22, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9625824

RESUMO

Overexpression and amplification of Met/HGF receptor has been detected in gastric cancer tissues and cell lines. In this study hepatocyte growth factor (HGF) and Met/HGF receptors were localized in 32 gastric cancer and adjacent normal gastric tissues by the avidin-biotin-peroxidase complex technique. HGF (87.5%) and Met/HGF receptors (68.8%) were demonstrated in gastric cancer tissues. A high positive rate of HGF (87.0%) and Met/ HGF receptors (82.6%) presented in intestinal type gastric cancer. HGF immunoreactivity in gastric cancer tissues was a significant and powerful prognostic indicator (relative risk 15.9; p=0.01). These data suggest that HGF and Met/HGF receptors are involved in the morphogenesis of intestinal type gastric cancer. HGF may have other mechanism that favor gastric cancer spread and independently affect survival.


Assuntos
Adenocarcinoma/química , Fator de Crescimento de Hepatócito/análise , Proteínas Proto-Oncogênicas c-met/análise , Neoplasias Gástricas/química , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Taxa de Sobrevida
16.
Oncol Rep ; 6(6): 1313-9, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10523704

RESUMO

It has been proposed that persistent oxidative stress accounts for the increased levels of DNA damage in cancer tissues. We have examined the profile of anti-oxidant enzymes in a transplanted hepatic tumor model by injecting N1S1 rat hepatoma cells into the liver of Sprague-Dawley rats. The transplanted N1S1 tumors displayed characteristics resembling human hepatocellular carcinoma. The immunoreactivities of catalase (CAT), manganese-superoxide dismutase (Mn SOD), copper/zinc-SOD (Cu/Zn SOD), and glutathione peroxidase (GPx) were found to decrease significantly. The enzyme activity in tumors decreased 26.2-, 4.2-, 4.5-, and 5.4-fold for CAT, Mn SOD, Cu/Zn SOD, and GPx, respectively, relative to those in normal liver tissue from the same animals. In contrast, the mRNA levels of CAT and GPx in tumors decreased only 5- and 2-fold, respectively, and the mRNA levels of Cu/Zn SOD and Mn SOD showed either no change or an increase as compared to those of normal liver tissue. The contents of 8-hydroxy-2'-deoxyguanosine (8-OH-dG) and thiobarbituric acid-reactive substances (TBARS) were comparable to those of normal controls. Furthermore, mitochondrial production of superoxide in tumors was 4 times lower than that in normal tissues. In conclusion, the data indicate that the reduced activities of anti-oxidant enzymes in the N1S1 tumor did not cause significant oxidative stress.


Assuntos
Antioxidantes/metabolismo , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas Experimentais/metabolismo , Estresse Oxidativo , Animais , Carcinoma Hepatocelular/patologia , Catalase/metabolismo , Glutationa Peroxidase/metabolismo , Humanos , Neoplasias Hepáticas Experimentais/patologia , Transplante de Fígado , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo
17.
Eur J Gastroenterol Hepatol ; 12(3): 351-5, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10750657

RESUMO

Establishing the diagnosis of small-bowel malignancy is sometimes an extremely difficult challenge owing to its non-specific symptoms. The mainstay of treatment is early recognition, diagnosis and surgical resection. The prognosis depends primarily on the degree of spread and stage at presentation. We present two cases with initially obscure presentations of a small-bowel tumour. One was a jejunal adenocarcinoma, but an initial upper gastrointestinal and small-bowel series did not disclose the lesion; the other was a primary ileal lymphoma, first thought to be diabetes mellitus gastroparesis. Therefore, a negative small-bowel series or presentation of a systemic disease-associated intestinal pseudo-obstruction or gastroparesis does not exclude the possibility of a small-bowel malignancy, if the clinical symptoms are not alleviated after prokinetic medications. The clinicians should further pursue the possibility of an obstructing lesion.


Assuntos
Adenocarcinoma/diagnóstico , Gastroparesia/etiologia , Neoplasias do Íleo/diagnóstico , Neoplasias do Jejuno/diagnóstico , Linfoma Folicular/diagnóstico , Adenocarcinoma/complicações , Idoso , Erros de Diagnóstico , Gastroscopia , Humanos , Neoplasias do Íleo/complicações , Neoplasias do Jejuno/complicações , Linfoma Folicular/complicações , Masculino , Tomografia Computadorizada por Raios X
18.
Med Hypotheses ; 63(3): 494-7, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15288375

RESUMO

Cataract is the leading cause of visual impairment in older adults in the world. Age-related lens opacities are common and are frequent causes of loss of vision. The incidence of cataract increases significantly with increasing age in women only. The onset coincides with estrogen deficiency that occurs after menopause. Hormone replacement therapy has proven beneficial to selected postmenopausal women. Estrogen effects on biological system are modulated via the estrogen receptors (ER) and/or estrogen metabolites. Although ER have been detected in ocular tissue, whether ER polymorphism is related to cataract is not known at present. The polymorphisms of estrogen metabolizing enzymes are also related to the serum concentration and activity of estrogen. Polymorphism such as cytochrome P450c17 (A2/A2), cytochrome P450c1A (vt/vt) will result in increased formation of catechol estrogen, while people with catechol-O-methyltransferase (COMT) polymorphism COMT (L/L) will have decreased metabolism of catechol estrogen and decreased level of methoxyestradiol. COMT was also involved in tamoxifen metabolism which may further decrease the activity of COMT in breast cancer patients treated with tamoxifen. It is known that a 4-7% increase in cataract was found in tamoxifen-treated breast cancer patients than non-user. The 7.0% COMT (L/L) genotype in general population corresponded well with the 4-7% of cataract formation in tamoxifen-treated breast cancer patients. Our hypothesis is that breast cancer patients with COMT (L/L) genotype may be at increased risk of cataract formation after tamoxifen treatment.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Catarata/genética , Catarata/metabolismo , Estrogênios/genética , Estrogênios/metabolismo , Predisposição Genética para Doença/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/complicações , Catarata/diagnóstico , Catarata/etiologia , Ensaios Clínicos como Assunto , Medicina Baseada em Evidências , Feminino , Testes Genéticos , Humanos , Masculino , Modelos Biológicos , Polimorfismo Genético , Medição de Risco/métodos , Fatores de Risco
19.
J Pediatr Surg ; 35(11): 1591-6, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11083430

RESUMO

PURPOSE: The aim of this study was to investigate the possible role of Fas and Fas ligand system in biliary atresia. METHODS: Immunohistochemical stains of Fas and Fas ligand (FasL) and in situ hybridization of Fas ligand messenger RNA (mRNA) were performed on paraffin-embedded liver specimens of 36 biliary atresia, 6 choledochal cysts, and 14 nontumorous parts of pediatric liver tumors. Apoptosis was detected by terminal deoxynucleotidyl transferase deoxy-UTP nick end labeling (TUNEL). The grade of liver fibrosis and results of bile drainage on the patients with biliary atresia were compared with the results of FasL expression. RESULTS: Fas protein was positive on the hepatocytes and bile ductule epithelia of all the livers examined and also positive on some monocytes around the portal area in all the biliary atresia patients. FasL protein was positive on bile ductule epithelia in 10 biliary atresia patients and also positive on some monocytes in most of the biliary atresia patients. Positive signals of FasL mRNA were noted on hepatocytes in 4 biliary atresia, bile ductule epithelia in 19 biliary atresia patients, and some monocytes in most of the biliary atresia patients. Apoptotic nuclei were present among monocytes in all the biliary atresia livers but present among bile ductule epithelia only on the BA with positive FasL mRNA signals on ductule epithelium. The fibrosis grade was similar between biliary atresia with positive FasL mRNA signals and negative signals. The bile drainage was better in the biliary atresia without positive FasL mRNA signals. CONCLUSIONS: Fas ligand expression on bile ductule epithelia in biliary atresia may be induced to counterattack the infiltrating lymphocytes. Although the factors for post-Kasai bile drainage are multiple, the authors suggest Fas ligand expression on bile ductule epithelia may be a poor prognostic factor by playing a role in the continuous damage and obliteration of intrahepatic bile ducts after Kasai operation.


Assuntos
Atresia Biliar/patologia , Cisto do Colédoco/patologia , Neoplasias Hepáticas/patologia , Glicoproteínas de Membrana/análise , RNA Mensageiro/análise , Sequência de Bases , Biomarcadores/análise , Distribuição de Qui-Quadrado , Criança , Pré-Escolar , Técnicas de Cultura , Proteína Ligante Fas , Feminino , Humanos , Imuno-Histoquímica , Hibridização In Situ , Masculino , Dados de Sequência Molecular , Probabilidade , Prognóstico , Valores de Referência , Sensibilidade e Especificidade
20.
Hepatogastroenterology ; 46(29): 2968-73, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10576384

RESUMO

BACKGROUND/AIMS: Cell kinetics are important indicators of the biological behavior of various human tumors. In this study, we evaluated the prognostic values of the proliferative factors including MIB-1 index, DNA ploidy and S-phase fraction, and further determined the independent prognostic factors in pancreatic head cancer after pancreatoduodenectomy. METHODOLOGY: Patients with pancreatic head cancer undergoing pancreatoduodenectomy were included. Cell proliferative parameters including MIB-1 index, DNA ploidy and S-phase fraction measured by flow cytometry were evaluated and compared with the conventional clinicopathologic factors. RESULTS: There were 21 resectable pancreatic head cancers. By univariate analysis MIB-1 index, cell differentiation and lymphovascular invasion were significant prognostic factors. The 5-year survival rate was 22.2% for overall patients and 29.2% for patients with MIB-1 < or = 11%, while it was 0% for MIB-1 index > 11%, p=0.011. Tumors without lymphovascular invasion had significantly better prognosis than those with lymphovascular invasion (median survival: 38 vs. 10 months, p=0.009). The median survival was significantly longer for well-differentiated cancers than for moderately and poorly differentiated cancers (44 vs. 11 and 9 months, p=0.038). There was no correlation between the MIB-1 index and the other 2 conventional prognostic factors. After multivariate analysis, only the MIB-1 index emerged as the independent prognostic factor. CONCLUSIONS: MIB-1 index played a significant role in the prognosis of the resectable pancreatic head cancer and could potentially complement the conventional factors in predicting the prognosis and determining the optimal treatment strategy. MIB-1 index was also an important independent prognostic factor.


Assuntos
Biomarcadores Tumorais/análise , Divisão Celular/fisiologia , Proteínas Nucleares/análise , Neoplasias Pancreáticas/cirurgia , Pancreaticoduodenectomia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos Nucleares , DNA de Neoplasias/análise , Feminino , Citometria de Fluxo , Humanos , Antígeno Ki-67 , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Células Neoplásicas Circulantes , Pâncreas/patologia , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Ploidias , Prognóstico , Fase S/fisiologia , Taxa de Sobrevida
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