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1.
Science ; 354(6309)2016 10 14.
Artículo en Inglés | MEDLINE | ID: mdl-27738143

RESUMEN

The biodiversity-productivity relationship (BPR) is foundational to our understanding of the global extinction crisis and its impacts on ecosystem functioning. Understanding BPR is critical for the accurate valuation and effective conservation of biodiversity. Using ground-sourced data from 777,126 permanent plots, spanning 44 countries and most terrestrial biomes, we reveal a globally consistent positive concave-down BPR, showing that continued biodiversity loss would result in an accelerating decline in forest productivity worldwide. The value of biodiversity in maintaining commercial forest productivity alone-US$166 billion to 490 billion per year according to our estimation-is more than twice what it would cost to implement effective global conservation. This highlights the need for a worldwide reassessment of biodiversity values, forest management strategies, and conservation priorities.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Bosques , Árboles/fisiología , Cambio Climático , Extinción Biológica
2.
Environ Monit Assess ; 159(1-4): 331-40, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19043792

RESUMEN

We evaluated the quality of data being collected for the Japanese National Forest Inventory (NFI). The inventory program commenced in 1999 but has not incorporated a quality assurance (QA) program; we sought to determine what effect this was having on the quality of data being collected. Forty-eight plots in four prefectures were measured by operational field teams and then remeasured by a control team that made careful and unhurried measurements. The paired data were evaluated, including diameter, total height, tree count, species richness, and topographic condition. Compared to the control team, all field teams of each prefecture tended to significantly underestimate all of the continuous variables. Most variables had larger variability in the inventory data than has been reported in the published literature. The findings of consistent bias and large variation in the field team measurements call for urgent implementation of a quality assurance program (extensive field training and regular remeasurement) in the Japanese NFI to improve data quality, and this conclusion could be applied to the inventory system of any country that does not include a QA program.


Asunto(s)
Monitoreo del Ambiente/normas , Control de Calidad , Árboles , Japón , Proyectos de Investigación
3.
Eur Radiol ; 17(9): 2262-7, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17447071

RESUMEN

We propose the hypothesis that the enlargement of the common bile duct (CBD) or gallbladder (GB) that is occasionally demonstrated on magnetic resonance cholangiopancreatography (MRCP) after secretin stimulation is caused by pancreatobiliary reflux. Recently, occult pancreatobiliary reflux (OPR) has been demonstrated in patients without morphological pancreatobiliary maljunction (MPBM). The aim of this study was to evaluate the efficacy of secretin-stimulating MRCP (SMRCP) in the diagnosis of pancreatobiliary reflux. The study included 14 patients with MPBM and 32 patients with a normal pancreatobiliary junction. OPR was evaluated by bile collection and diagnosed in seven of the 32 patients. All the patients underwent SMRCP; the related findings were considered positive when enlargement of the CBD or GB was observed. Positive findings on SMRCP were observed in all MPBM patients. In the patients with normal pancreatobiliary junction, there was significant difference between the mean amylase levels in the patients with positive and negative SMRCP findings (mean, 4,755.7 and 29.7 IU/l). The sensitivity and specificity of SMRCP for diagnosing OPR was 85.7% and 68.0%, respectively. SMRCP provides a non invasive method for excluding PBR and can identify patients who could benefit from bile duct sampling to diagnose OPR.


Asunto(s)
Conductos Biliares/patología , Reflujo Biliar/diagnóstico , Pancreatocolangiografía por Resonancia Magnética , Conductos Pancreáticos/patología , Amilasas/análisis , Reflujo Biliar/fisiopatología , Femenino , Enfermedades de la Vesícula Biliar/diagnóstico , Enfermedades de la Vesícula Biliar/fisiopatología , Humanos , Masculino , Enfermedades Pancreáticas/diagnóstico , Enfermedades Pancreáticas/fisiopatología , Estudios Prospectivos , Secretina , Sensibilidad y Especificidad
5.
Nihon Rinsho ; 60(8): 1580-4, 2002 Aug.
Artículo en Japonés | MEDLINE | ID: mdl-12187754

RESUMEN

It is well recognized that diabetes mellitus develop a variety of complications during the course of disease, such as diabetic triopathy. After one to two decades of overt disease, approximately 30-60% of diabetics develop clinical signs of visceral autonomic neuropathy. Peptic ulcer patients with diabetes mellitus have these complicated backgrounds. The prevalence of peptic ulcer disease in asymptomatic diabetic patients was reported as 5.3% to 7.3% in Japan. We evaluated the efficacy of Helicobacter pylori eradication therapy in peptic ulcer patients with non-insulin dependent diabetes mellitus. The cure rate of peptic ulcer and gastritis score at 8 weeks after eradication therapy is similar with non-diabetic patients. Our data suggests that the eradication of Helicobacter pylori becomes a first therapy in peptic ulcer patients with non-insulin dependent diabetes mellitus.


Asunto(s)
Complicaciones de la Diabetes , Úlcera Péptica/etiología , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/tratamiento farmacológico , Helicobacter pylori , Humanos , Úlcera Péptica/tratamiento farmacológico
6.
Int J Cancer ; 98(6): 833-7, 2002 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-11948459

RESUMEN

c-erb-2 amplification and overexpression are currently attracting a great deal of attention because a new adjuvant therapy using an antibody against the c-erbB-2 gene product, trastuzumab (Herceptin; Genentech, Inc., South San Francisco, CA), has proved effective in treating breast cancer with amplification and/or overexpression of c-erbB-2. Aberrations of c-erbB-2 have also been detected in ovarian, endometrial and gastric carcinomas at varied frequencies. Amplification of the c-erbB-2 locus (17q12-q21.32), overexpression of c-erbB-2 protein (p185) and serum levels of soluble c-erbB-2 protein fragments (p105) were examined in gastric cancer patients using fluorescence in situ hybridization (FISH), immunohistochemistry and enzyme-linked immunosorbent assay (ELISA), respectively. Overexpression of c-erbB-2 protein was found in 29 (8.2%) of the 352 gastric carcinomas analyzed. In FISH analysis, all tumors with 3+ immunostaining and 1 of 5 tumors with 2+ staining showed high-level amplification of c-erbB-2. Pre-operative serum p105 was quantified in serum specimens from 129 patients with gastric cancer and 28 patients with benign diseases. There were no significant differences in the serum p105 levels among 11 patients with c-erbB-2-overexpressing carcinomas, 118 patients with c-erbB-2 non-overexpressing carcinomas and 28 controls, although a single case of gastric carcinoma overexpressing c-erbB-2 with extensive liver metastasis had a higher level than the cut-off value. The mechanisms of overexpression of p185 and high-level amplification of c-erbB-2 in gastric adenocarcinomas seem similar to those well-established in breast cancers. Patients having gastric adenocarcinoma with c-erbB-2 amplification are potential candidates for a new adjuvant therapy using humanized monoclonal antibody.


Asunto(s)
Adenocarcinoma/metabolismo , Receptor ErbB-2/metabolismo , Neoplasias Gástricas/metabolismo , Adenocarcinoma/genética , Adulto , Anciano , Anciano de 80 o más Años , Cromosomas Humanos Par 17 , Ensayo de Inmunoadsorción Enzimática , Femenino , Amplificación de Genes , Humanos , Técnicas para Inmunoenzimas , Hibridación Fluorescente in Situ , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Estadificación de Neoplasias , Receptor ErbB-2/genética , Neoplasias Gástricas/genética
7.
Gastric Cancer ; 1(2): 118-124, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11957055

RESUMEN

BACKGROUND: We conducted a case-control study to evaluate whether patients with severe gastric atrophy (indicated by serum pepsinogen concentration) have a high risk of gastric cancer.METHODS: At the time of diagnosis of gastric cancer, sera from 301 patients (cases) and 602 sex- and age-matched cancer-free individuals (controls) were tested for the presence of anti- Helicobacter pylori IgG antibody (HM-CAP enzyme-linked immunoassay [ELISA] kit; Kyowa Medix, Tokyo, Japan) and serum pepsinogen (PG) levels (PG I and II Riabead Kits; Dainabot, Tokyo, Japan). We defined positivity for pepsinogen a pepsinogen I concentration of less than 70 ng/mL and a PG I/II ratio of less than 3.0. We categorized the subjects according to serum pepsinogen levels and anti- Helicobacter pylori IgG antibody, creating four categories.RESULTS: Of the 301 cancer cases, 177 had positive serum pepsinogen levels, and 172 were positive for anti- Helicobacter pylori IgG antibody. The category in which subjects had positive serum pepsinogen levels and were negative for anti- Helicobacter pylori IgG antibody had the highest proportion (76.9%) of individuals with gastric cancer and the highest odds ratio (4.20) of the four categories. The odds ratios were 2.55 (95% confidence interval; 1.92-3.88) for positive serum pepsinogen levels and 0.93 (95% confidence interval; 0.63-1.27) for positive anti- Helicobacter pylori IgG antibody.CONCLUSION: These results suggest that patients with positive serum pepsinogen levels who are negative for IgG antibody to Helicobacter pylori, constitute a high-risk group for gastric cancer. Helicobacter pylori infection is associated with the development of gastric cancer by providing a suitable environment i.e., severe gastric atrophy, for carcinogenesis of the gastric mucosa.

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