Intra-abdominal fat burden discriminated in vivo using proton magnetic resonance spectroscopy

Objective: To assess proton magnetic resonance spectroscopy (¹H‐MRS) as a means to distinguish among mice with disparate intra‐abdominal body fat compositions, and to measure changes in intra‐abdominal fat burden during weight loss and regain. Research Methods and Procedures: Intra‐abdominal fat burden was analyzed as a ratio of integrated areas under the curves of fat to water ¹H‐MRS signals collected from a region of interest standardized across B6.V‐Lep^ob, C57BL/6, and A‐ZIP/F mice that exhibited various genotypically related body fat compositions, ranging from obese (B6.V‐Lep^ob) to minimal body fat (A‐ZIP/F). ¹H‐MRS analysis of fat burden was compared with intra‐abdominal fat volume and with a single cross‐sectional intra‐abdominal fat area calculated from segmented magnetic resonance images. Similar measurements were made from obese B6.V‐Lep^ob mice before, during, and after they were induced to lose weight by leptin administration. Results: Relative amounts of intra‐abdominal fat analyzed by ¹H‐MRS differed significantly according to body composition and genotype of the three strains of mice (p < 0.05). Intra‐abdominal fat assessed by ¹H‐MRS correlated with both intra‐abdominal fat volume (r = 0.88, p < 0.001) and body weight (r = 0.82, p < 0.001) among, but not within, all three genotypes. During weight loss and regain, there was a significant overall pattern of changes in intra‐abdominal fat quantity that occurred, which was reflected by ¹H‐MRS (p = 0.006). Discussion: Results support the use of localized ¹H‐MRS for assessing differences in intra‐abdominal fat. Refinements in ¹H‐MRS voxel region of interest size and location as well as instrument precision may result in improved correlations within certain body compositions.     

Ex vivo hypothermic recirculatory adenoviral gene transfer to the transplanted pig heart

BACKGROUND: To facilitate the application of adenoviral gene therapy in clinical heart transplantation, we developed an ex vivo hypothermic recirculatory adenoviral gene transfer method to the transplanted pig heart. METHODS: Experimental animals were assigned into three groups; controls, 1x10(8) plaque-forming units (pfu)/ml group and 1x10(9) pfu/ml group. During the 30 min gene transfer perfusion, 200 ml of University of Wisconsin solution containing the adenoviral vector was recirculated through the coronary vessels. The myocardial temperature was maintained below 4 degrees C and the perfusion pressure was adjusted at 50 mmHg. RESULTS: Cardiac myocyte transduction efficiencies in the 1x10(8) pfu/ml group were 0.04% and 0.07%, whereas transduction efficiencies in the 1x10(9) pfu/ml group were widely distributed from 0.45% to 22.62%. The gene transduction efficiency increased with the virus titer. Additionally, no difference in the transduction efficiency was observed between different segments of the left ventricle. The current gene transfer method at 1x10(9) pfu/ml of adenovirus titer enabled homogeneous gene transduction into the transplanted pig heart up to a maximum of 22.62%. CONCLUSIONS: This model can be applied to a large isolated heart and will greatly facilitate the investigation of gene therapy in large animal models of heart transplantation.     

神经肽Y对心室肌细胞离子通道的影响

采用全细胞膜片钳技术观察神经肽Y(neuropeptide Y,NPY)对心室肌细胞离子通道的影响。结果如下：(1)NPY浓度在1．0～100nmol/L范围内剂量依赖性抑制大鼠心室肌细胞I_(Ca-L),IC_(50)值为1．86nmol/L。NPY对I_(Ca-L)的I-V曲线的最大峰值电位、激活和失活电位均无显著影响。NPY对去甲肾上腺素(norepinephrine,NE)增加的I_(Ca-L)有显著抑制作用。(2)NPY对人鼠心室肌细胞I_(Na/Ca)有显著抑制作用。10nmol/L NPY使前向I__(Na/Ca)由(0．27±0．11)pA/pF减小为(0．06±0．01)pA/pF;反向I__(Na/Ca)由(0．45±0．12)pA/pF降为(0．27±0．09)pA/pF(P＜0．05,n=4)。(3)NPY对大鼠心室肌细胞I_(to)有显著增强作用。10 nmol/L NPY使I_(to)由(12．5±0．70)pA/pF增加至(14．7±0．59)pA/pF(P＜0．05,n=4)。(4)10nmol/L NPY对大鼠心室肌细胞I_(Na)没有显著影响。(5)10nmol/L NPY对豚鼠心室肌细胞I_K无明显影响。研究结果证实,NPY抑制大鼠心室肌细胞I_(Ca-L)和I_(Na/Ca),增强I_(to)对I_Na和豚鼠心审肌细胞I_K没有显著作用,表明NPY对上述主要离子通道的效应与NE的效应相拮抗。     

Study of the interaction between doxepin hydrochloride and bovine serum albumin by spectroscopic techniques

The binding of doxepin hydrochloride (DH) to bovine serum albumin (BSA) was investigated by spectroscopic (fluorescence, UV–vis absorption and circular dichroism) techniques. The binding parameters have been evaluated by fluorescence quenching method. The thermodynamic parameters, ΔH°, ΔS° and ΔG° calculated at different temperatures indicated that the hydrogen bond and hydrophobic forces played a major role in the interaction of DH with BSA. Based on the Förster's theory of non-radiation energy transfer, the binding average distance, r between the donor (BSA) and acceptor (DH) was evaluated and found to be 2.7 nm. Spectral results observed showed that the binding of DH to BSA induced conformational changes in BSA. The effect of common ions on the binding of DH to BSA was also examined.     

Is the chimpanzee, Pan troglodytes, an endangered species? It depends on what “endangered” means

I review information on the status in the wild of the robust chimpanzee, Pan troglodytes, and consider whether this evidence is consistent with the designation of P. troglodytes as Endangered in the International Union for the Conservation of Nature and Natural Resources (IUCN) Red List, and with public statements to the effect that great apes as a whole will be extinct within a few decades. Chimpanzees remain widespread in tropical Africa, occurring in a variety of forested habitats. Estimates of total surviving numbers have increased from about 200,000 in the 1980s to a maximum of almost 300,000 in 2003. However, this apparent increase comes about from new survey data, rather than representing a measured increase in actual population numbers. Infectious disease decimated several chimpanzee populations during the 1990s, and data from parts of Gabon, extrapolated to that country as a whole, suggest a major decline in great ape populations caused by disease and hunting. However, accurate data on population numbers are absent for the majority of wild chimpanzee populations. I found reports of the presence of Pan troglodytes in at least 51 national parks in at least 19 countries; some of these parks have been established very recently. Chimpanzees also occur in many non-park conservation areas. A set of large, well-protected parks could safeguard chimpanzees for the foreseeable future. Although many African parks do not function well at present, mechanisms to improve their function are understood and available. By a strict application of IUCN threat criteria, P. troglodytes can be considered Endangered, based on estimated rates of past decline and on the species long generation time. Relatively speaking, however, P. troglodytes is less endangered than are orangutans or gorillas, and the species is unlikely to go extinct by the year 2100, especially if existing conservation measures improve. The IUCN threat-rating system has become overly complex; the system can produce results that do not accord with common sense and these results must therefore be interpreted with care.     

Spatial distribution of primates in a mosaic of colonizing and old growth forest at Ngogo, Kibale National Park, Uganda

Primate censuses were conducted in a mosaic of colonizing (two locations) and old-growth forests using line transect methods at the Ngogo study site, Kibale National Park, Uganda. Black and white colobus monkeys (Colobus guereza) were encountered more frequently in the colonizing forests than in the old growth forest, while chimpanzees (Pan troglodytes) were encountered more frequently in the old growth forest than in colonizing forests. Although not significant, results suggest that blue monkeys (Cercopithecus mitis) frequented colonizing forests more often than old growth forest. The encounter rates of mangabey (Lophocebus albigena), and redtail (Cercopithecus ascanius) groups were ambiguous with their density being higher in some colonizing forests but not others as compared to old-growth forest. No significant differences were detected for baboons (Papio anubis), Lhoests (Cercopithecus lhoesti), and red colobus monkeys (Piliocolobus tephroscales). The conversion of forests to farmland is one of the major problems encountered in primate conservation. This study shows that secondary forests replacing anthropogenic grasslands have the potential of supporting some primate species such as black and white colobus, redtail monkeys, and possibly blue monkeys. Therefore, such areas should not be given up but should be conserved for the benefit of primates that can survive in secondary forests; as the forests mature further, primate species that are adapted to old growth forest will colonize the area provided there is a nearby source.     

High genetic diversity vs. low genetic differentiation in Nouelia insignis (Asteraceae), a narrowly distributed and endemic species in China, revealed by ISSR fingerprinting

BACKGROUND AND AIMS: Nouelia insignis Franch., a monotypic genus of the Asteraceae, is an endangered species endemic in Yunnan and Sichuan Provinces of China. Most of the populations are seriously threatened. Some of them are even at the brink of extinction. In this study, the genetic diversity and differentiation between populations of this species were examined in two drainage areas. METHODS: DNA fingerprinting based on inter-simple sequence repeat polymorphisms was employed to detect the genetic variation and population structure in the species. KEY RESULTS: Genetic diversity at species level was high with P=65.05% (percentage of polymorphic loci) and Ht=0.2248 (total genetic diversity). The coefficient of genetic differentiation among populations, Gst, which was estimated by partitioning the total gene diversity, was 0.2529; whereas, the genetic differentiation between populations in the Jinsha and Nanpan drainage areas was unexpectedly low (Gst=0.0702). CONCLUSIONS: Based on the genetic analyses of the DNA fingerprinting, recent habitat fragmentation may not have led to genetic differentiation or the loss of genetic diversity in the rare species. Spatial apportionment of fingerprinting polymorphisms provides a footprint of historical migration across geographical barriers. The high diversity detected in this study holds promise for conservation and restoration efforts to save the endangered species from extinction.     

Landscape evaluation for ecosystem planning

Landscape evaluation is important in the conservation of biodiversity and sustainable development. The objective of this paper is to review and explore methods for evaluation of landscapes for ecosystem planning. Ecosystem planning is the process of land use decision-making that considers organisms and processes that characterize the ecosystem as a whole. Risk assessments, precautionary principles, adaptive management and scenario approaches are adopted to cope with the uncertainty of nature, which is an obstacle in ecosystem planning. Special attention is needed in the analysis of status and troubleshooting in the planning scheme, which is a selection of the appropriate approach and model to find problems in the present situation. There are two approaches to set targets in ecosystem planning, the species approach and the ecosystem approach. The species approach aims to protect particular species, and the ecosystem approach aims to protect total ecosystems including the species. In Europe, ecotope or biotope mapping has been developed in ecosystem planning. An ecotope is often identified by vegetation that represents a group of wildlife, but many species require combinations of different ecotopes. Landscapes have come to be recognized as a unit for ecosystem planning. Potential assessment is a method to estimate a potential of a local space or a landscape to realize an ecosystem or species habitat, and this method has been used in HEP and GAP analysis in the USA and Ecological Networks in Europe. Some examples of ecosystem planning of national and regional scales in Japan are introduced.     

The Effect of Wildlife Conservation on Local Perceptions of Risk and Behavioral Response

In this study, we examine the effect of Tarangire National Park (TNP) on local perceptions of risk and how these perceptions may influence behavioral responses. Data were collected during 2004–2005 through household surveys and participatory risk mapping (PRM) in eight villages east of TNP. By identifying and rank-ordering respondents’ perceived risks, PRM enhances understanding of the nature and variation of risks faced within a population by distinguishing between the incidence and severity of subjective risk perceptions. Results indicate that proximity to the park has a strong effect on the type and severity of perceived risks. Within villages close to the park, however, behavioral response to perceived risks varies considerably. This study contributes to an appreciation of how behavioral response to environmental and socioeconomic factors is mediated by human perception.