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1.

Extensive transfer of tilapia between lakes throughout East Africa has often led to hybridisation with indigenous fish populations. The endemic Oreochromis hunteri of Lake Chala, an isolated crater lake near Mount Kilimanjaro, is potentially susceptible to introgression from a species formerly identified as Oreochromis korogwe, introduced ~ 30 years ago. We combined whole-body geometric morphometry on 104 specimens of both taxa with molecular phylogenetic analysis of mitochondrial loci from 15 O. hunteri and 9 O. cf. korogwe specimens to assess whether hybridisation has occurred. Using fishes from Lake Jipe and Nyumba ya Mungu reservoir, we expanded our analysis to all four Oreochromis species currently inhabiting the Upper Pangani River system to determine the closest relative of O. hunteri, and hence the possible source population of the ancestral species that colonised Lake Chala. Our results indicate no interbreeding occurs between O. hunteri and O. cf. korogwe, and suggest O. jipe to be the closest living relative of O. hunteri. The introduced O. cf. korogwe is a phenotypically uniform but genetically variable population, the identity of which remains unknown. The high haplotype diversity of O. hunteri is consistent with fossil evidence indicating that its ancestor colonised Lake Chala at least 25,000 years ago.

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2.
Contribución al conocimiento de algunos fringílidos de la región costanera del Perú (con descripciones originales de nuevas subespecies) por Maria Koepcke.

Estudiando las comunidades vitales naturales de las lomas de la costa peruana hemos encontrado en algunas especies de aves nuevas razas geográficas. Además fué posible hallar nuevos datos respecto a la posición sistemática y distribución de otras. En este trabajo trato solamente de los fringílidos. Se describe tres subespecies nuevas.

Sporophila obscura pacifica nov. subspec, más grande y de coloración más grisácea que las otras razas de esta especie. Vive en la costa del Centro y Sur del Perú desde las lomas de Lachay (90 kms. al norte de Lima) hasta Atiquipa (cerca de Chala).

Zonotrichia capensis illescasensis nov. subspec. es un endemismo de las lomas del Cerro Illescas (Norte del Perú, a los 6o Lat. S.) que tienen una situación geográfica muy aislada. Se distingue de las otras razas de Zonotrichia capensis existentes en la costa y sierra del Norte del Perú y Sur de Ecuador (peruviensis, huancabambae, y costaricensis) sobre todo por su coloración más grisácea, las manchas negras y rojizas en el cuello y pecho más pálidas y menos desarrolladas, los bordes de las plumas del dorso y de las alas color ocre‐arena en vez de rojizo. De la raza peruviensis tan común en las lomas de la costa centro y sur del Perú, se distingue además por su tamaño menor y su canto diferente.

Phrygilus alaudinus humboldti nov. subspec. es una raza costeña del Norte del Perú y Sur de Ecuador que se caracteriza por su tamaño pequeño y la coloración algo más pálida del macho. Es muy común en las lomas del Cerro Illescas. En las otras lomas a lo largo de la costa central y sur del Perú se observa la raza más grande bipartitus que además es típica en las vertientes andinas desde el Sur de Ecuador hasta el Sur del Perú.

La población de Sicalis luteola existente en el lado occidental de los Andes peruanos y en los valles interandinos norperuanos se identifica como perteneciente a la raza geográfica bogotensis, mientras que la Sicalis raimondii se reconoce de nuevo como otra especie. Ambas fueron confundidos y reunidos bajo un mismo nombre de especie por varios autores, pero pertenecen a dos especies distintas que se presentan en las mismas áreas, distinguiéndose considerablemente en su canto y lugares de anidación. También en la coloración presentan sus características propias, como el anillo amarillo alrededor del ojo y la coloración general más pardo‐verduzca en Sicalis luteola y, por otro lado, la coloración más gris y reducción de las manchas oscuras en el dorso en Sicalis raimondii.  相似文献   

3.
The 3rd International Conference on Proteomics & Bioinformatics (Proteomics 2013)

Philadelphia, PA, USA, 15–17 July 2013

The Third International Conference on Proteomics & Bioinformatics (Proteomics 2013) was sponsored by the OMICS group and was organized in order to strengthen the future of proteomics science by bringing together professionals, researchers and scholars from leading universities across the globe. The main topics of this conference included the integration of novel platforms in data analysis, the use of a systems biology approach, different novel mass spectrometry platforms and biomarker discovery methods. The conference was divided into proteomic methods and research interests. Among these two categories, interactions between methods in proteomics and bioinformatics, as well as other research methodologies, were discussed. Exceptional topics from the keynote forum, oral presentations and the poster session have been highlighted. The topics range from new techniques for analyzing proteomics data, to new models designed to help better understand genetic variations to the differences in the salivary proteomes of HIV-infected patients.  相似文献   

4.
Oxygen- and carbon-14-based primary production estimates from9–16 h in vitro incubations were compared in lakes Huronand Michigan. For surface mixing layer compansons, gross O2/14Cphotosynthetic quotients (gross PQ) averaged 2.2, and net O2/14Cphotosynthetic quotients (net PQ) averaged 1.4. The mean grossPQ is consistent with a theoretical P0 based on the CO2 andNO3 assimilation ratio. However, within the deep chlorophylllayer, gross PQ and net PQ averaged 4.9 and 2.8 respectively.These higher values were likely due to excess NO3 reductionat the expense of CO2 uptake. Thus, during short experimentsunder low light conditions, oxygen evolution and CO2 uptakemay not be tightly coupled. In vitro and in situ O2 productionestimates were compared in four diurnal (dawn to dusk) experimentsin Lake Huron. In situ production estimates were determinedby measuring water-mass oxygen changes and oxygen transfer acrossthe air-water interface. In situ production estimates were approximatelytwice in vitro production estimates for both surface mixinglayer and deep chlorophyll layer comparisons. The differencebetween estimates was attributable to containment effects manifestin 13–16 h bottle incubations. Short-term (1–2 h)in vitro production was also compared to diurnal in vitro production.Rates of short-term production were {small tilde}1.6 times higherthan rates of diurnal production, suggesting that short-termin vitro production experiments may provide reasonable estimatesof in situ primary production.  相似文献   

5.
To determine sleep effects on baro- andventilatory responses to transient chemo- and barostimulation inAfrican-Americans and Caucasians, 26 nonobese normotensive youngsubjects (13 African-Americans and 13 Caucasians) were studied awakeand in non-rapid-eye movement (NREM) and rapid-eye-movement sleepduring induced transient hypoxemia (N2), hypertension(phenylephrine, PE), and concomitant hypoxemia and hypertension(N2 + PE). Arterial blood pressurewas recorded by plethysmographic volume clamp, minute ventilation bypneumotachograph, and arterial O2saturation by pulse oximeter. For all subjects, chronotropicbaroresponse (pulse interval/systolic blood pressure, where  is change) increased with NREM sleep(P = 0.007). Baroresponse slope wasgreater in Caucasians than in African-Americans (ANOVA, P = 0.02). Hypoxemic ventilatoryresponse (minute ventilation/arterial O2 saturation) was greater inAfrican-Americans than in Caucasians in NREM sleep(P = 0.01), as was hypoxemicattenuation of baroresponse (N2 + PE, P = 0.03). These data suggestsleep-related differences in arterial chemo- and baroreceptor responsesin normal young African-Americans and Caucasians, which may haveimplications concerning development of systemic hypertension.

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6.
75Se and 109Cd tracers were used to study the binding of Se and Cd to plasma proteins at various SeO32? doses and times up to 24 h after the simultaneous subcutaneous administration of SeO32? and CdCl2 to adult male rats. The simultaneous injection of CdCl2 and SeO32? markedly increased both Se and Cd plasma levels over that in control animals. Gel permeation chromatography of plasma indicated that at all times up to 24 h Cd and Se were bound in an atomic ratio of approx. 1 : 1 in 330 000 and 130 000 dalton fractions. From 4 to 24 h, Cd and Se appeared in the 420 000 dalton fraction, also with an atomic ratio of approx. 1 : 1. The 330 000 dalton molecules appeared to have a maximal binding capacity for the Cd-Se complex at a concentration of approx. 30 μmol/ml of plasma, while the 130 000 and 420 000 dalton molecules show a higher binding capacity. Studies in vitro revealed that SeO32? does not interact directly with Cd and plasma proteins. It is metabolized by erythrocytes to a form that interacts in an atomic ratio of 1 : 1 with Cd to form a protein-bound complex of 130 000 daltons.  相似文献   

7.
We investigatedthe effects of 3 wk of moderate- (21 m/min, 8% grade) andhighintensity treadmill training (31 m/min, 15% grade) on1) monocarboxylate transporter 1 (MCT-1) content in rat hindlimb muscles and the heart and2) lactate uptake in isolated soleus(Sol) muscles and perfused hearts. In the moderately trained groupMCT-1 was not increased in any of the muscles [Sol, extensor digitorum longus (EDL), and red (RG) and white gastrocnemius(WG)] (P > 0.05). Similarly,lactate uptake in Sol strips was also not increased(P > 0.05). In contrast, in theheart, MCT-1 (+36%, P < 0.05) andlactate uptake (+72%, P < 0.05)were increased with moderate training. In the highly trained group,MCT-1 (+70%, P < 0.05) and lactateuptake (+79%, P < 0.05) wereincreased in Sol. MCT-1 was also increased in RG (+94%,P < 0.05) but not in WG and EDL(P > 0.05). In the highly trainedgroup, heart MCT-1 (+44%, P < 0.05)and lactate uptake (+173%, P < 0.05) were increased. In conclusion, it has been shown that1) in both heart and skeletal musclelactate uptake is increased only when MCT-1 is increased; 2) training-induced increases inMCT-1 occurred at a lower training intensity in the heart than inskeletal muscle; 3) in the heart, lactate uptake was increased much more after high-intensity training than after moderate-intensity training, despite similar increases inheart MCT-1 with these two training intensities; and4) the increases in MCT-1 occurredindependently of any changes in the heart's oxidative capacity (asmeasured by citrate synthase activity).

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8.
This study was performed to obtain a characterization of the changes in plasma transferrin (Tf, g/L) in sepsis. More than four hundred determinations of Tf, and of a large series of simultaneously collected blood and hemodynamic variables, were obtained in 17 patients with post-traumatic sepsis. Tf during sepsis was consistently low (mean ± SD = 1.46 ± 0.46) however fluctuated markedly according to changes in metabolic and hemodynamic patterns. Regression analysis showed that decreases in Tf were simultaneously correlated with the plasma lipid pattern (in particular with decreasing cholesterol and increasing triglycerides), with decreases in albumin and peripheral O2 extraction, and with increasing cardiac index (p < 0.001 for all). Decreases in Tf were moderated by increasing the parenteral amino acid dose (p < 0.001). Combinations of these variables in multiple regressions explained nearly 80% of the variability of Tf. There were no similar correlations for other acute phase proteins except ceruloplasmin, which showed opposite changes compared to those of Tf. These results show that within the hypotransferrinemia which characterizes sepsis, Tf may oscillate remaining strongly correlated with changes in metabolic and hemodynamic patterns, which may account for nearly 80% of the variability of Tf.  相似文献   

9.
Cotyledons of light-grown soybean (Glycine max L. var Wayne) seedlings were used as a model system to study the possibility that aging requires qualitative changes in protein synthesis. Cotyledons reached a final stage of senescence and then abscised about 22 days after imbibition. Cotyledon senescence was reversed at 20 days after germination by epicotyl removal. Thereafter, the cotyledons regained much of the chlorophyll, RNA, protein, and polyribosomes lost during aging.

Total poly(A)mRNA was extracted from 4-, 12-, 20-day-old, and rejuvenated cotyledons and translated in a wheat germ system. Comparison of translation products on two-dimensional O'Farrell gels showed that many translation products increased in quantity during aging, while roughly half as many decreased. Rejuvenation returned the translation products to approximately 4-day-old levels in roughly half of those products which were diminished with age. Conversely, almost one-third of the products which had increased with age decreased with rejuvenation. None of the translation products were totally lost nor were newly synthesized products detected during aging. Therefore, aging in this system probably does not involve complete gene repression or depression. The observation that epicotyl removal causes a reversal in the levels of various proteins synthesized in vitro was corroborated by similar observations following in vivo labeling of cotyledon sections and analysis by SDS-polyacrylamide gel electrophoresis and fluorography. Densitometric scans of fluorograms revealed a gradual shift in profiles of both in vitro and in vivo translation products during aging. Rejuvenated cotyledon proteins had a profile resembling that of 4-day-old cotyledons. The overall level of [35S]methionine incorporation into protein in vivo declined gradually during aging but was restored to 4-day-old levels within 2 days after epicotyl removal.

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10.

Background

Socio-demographic factors and area of residence might influence the development of esophageal and gastric cancer. Large-scale population-based research can determine the role of such factors.

Methods

This population-based cohort study included all Swedish residents aged 30–84 years in 1990–2007. Educational level, marital status, place of birth, and place of residence were evaluated with regard to mortality from esophageal or gastric cancer. Cox regression yielded hazard ratios (HR) with 95% confidence intervals (CI), adjusted for potential confounding.

Results

Among 84 920 565 person-years, 5125 and 12 230 deaths occurred from esophageal cancer and gastric cancer, respectively. Higher educational level decreased the HR of esophageal cancer (HR = 0.61, 95%CI 0.42–0.90 in women, HR = 0.71, 95%CI 0.60–0.84 in men) and gastric cancer (HR = 0.80, 95%CI 0.63–1.03 in women, HR = 0.73, 95%CI 0.64–0.83 in men). Being unmarried increased HR of esophageal cancer (HR = 1.64, 95%CI 1.35–1.99 in women, HR = 1.64, 95%CI 1.50–1.80 in men), but not of gastric cancer. Being born in low density populated areas increased HR of gastric cancer (HR = 1.23, 95%CI 1.10–1.38 in women, HR = 1.37, 95%CI 1.25–1.50 in men), while no strong association was found with esophageal cancer. Living in densely populated areas increased HR of esophageal cancer (HR = 1.31, 95%CI 1.14–1.50 in women, HR = 1.40, 95%CI 1.29–1.51 in men), but not of gastric cancer.

Conclusion

These socio-demographic inequalities in cancer mortality warrant efforts to investigate possible preventable mechanisms and to promote and support healthier lifestyles among deprived groups.  相似文献   

11.
The major psychoactive Δ9-tetrahydrocannabinol (THC) and the non-psychoactive cannabinol (CBN) of cannabidiol (CBD) can both stimulate and inhibit testicular testosterone (T) production in vitro and in vivo. At nanomolar concentrations, these cannabinoids stimulate T production by decapsulated mouse testes while, in micromolar amounts, the effects are markedly inhibitory.  相似文献   

12.
A field experiment involving drought and warming manipulation was conducted over a 6-year period in a Mediterranean shrubland to simulate the climate conditions projected by IPCC models for the coming decades (20% decreased soil moisture and 1°C warming). We investigated P and K concentration and accumulation in the leaves and stems of the dominant species, and in soil. Drought decreased P concentration in Globularia alypum leaves (21%) and in Erica multiflora stems (30%) and decreased K concentration in the leaves of both species (20% and 29%, respectively). The general decrease of P and K concentration in drought plots was due to the reduction of soil water content, soil and root phosphatase activity and photosynthetic capacity that decreased plant uptake capacity. Warming increased P concentration in Erica multiflora leaves (42%), but decreased it in the stems and leaf litter of Erica multiflora and the leaf litter (33%) of Globularia alypum, thereby demonstrating that warming improved the P retranslocation and allocation from stem to leaves. These results correlate with the increase in photosynthetic capacity and growth of these two dominant shrub species in warming plots. Drought and warming had no significant effects on biomass P accumulation in the period 1999–2005, but drought increased K accumulation in aboveground biomass (10 kg ha−1) in Globularia alypum due to the increase in K concentration in stems. The stoichiometric changes produced by the different responses of the nutrients led to changes in the P/K concentration ratio in Erica multiflora leaves, stems and litter, and in Globularia alypum stems and litter. This may have implications for the nutritional value of these plant species and plant–herbivore relationships. The effects of climate change on P and K concentrations and contents in Mediterranean ecosystems will differ depending on whether the main component of change is drought or warming.  相似文献   

13.
In this study, the levels of aflatoxin B1 (AFB1), ochratoxin A (OTA), zearalenone (ZEN), deoxynivalenol (DON) and fumonisins (FUM) in unprocessed cereals (n = 189) and cereal-based products (n = 61) were determined using validated ELISA methods. All samples originated from either conventional or organic production corresponded to the 2015 harvest in Croatia. Based on the mean mycotoxin concentrations, the risk for the consumer to exceed the tolerable daily intake (TDI) for these toxins by the consumption of both types of cereals and cereal-based products was assessed. Mycotoxin contamination of organic cereals and organic cereal-based products was not significantly different (p > 0.05). Given that the exposure assessment resulted in a small fraction of the TDI (maximum: DON, 12% of TDI), the levels of the investigated mycotoxins in both types of cereals and cereal-based products from the 2015 harvest did not pose a human health hazard.  相似文献   

14.
15.
Bending of 15 to 24° is observed within crystal structures ofB-DNA duplexes, is strongly sequence-dependent, and exhibits no correlation with the concentration of MPD (2-methyl-2,4-pentanediol) in the crystallizing solution. Two types of bends are observed: facultative bends or flexible hinges at junctions between regions of G·C and A·T base-pairs, and a persistent and almost obligatory bend at the center of the sequence R-G-C-Y. Only A-tracts are characteristically straight and unbent in every crystal structure examined to date. A detailed examination of normal vector plots for individual strands of a double helix provides an explanation, in terms of the stacking properties of guanine and adenine bases. The effect of high MPD concentrations, in both solution and crystal, is to decrease local bending somewhat without removing it altogether. MPD gel retardation experiments provide no basis for choosing among the three models that seek to explain macroscopic curvature of DNA by means of microscopic bending: junction bending, bent A-tracts, or bent general- sequence DNA. Crystallographic data on the straightness of A-tracts, the bendability of non-A sequences, and the identity of inclination angles in A-tract and non-A-tractB-DNA support only the general-sequence bending model. The pre-melting transition observed in A-tract DNA probably represents a relaxation of stiff adenine stacks to a flexible conformation more typical of general-sequence DNA.  相似文献   

16.
On the basis of cell shape, refractility under phase optics, spontaneous beating and nucleolar number, two cell types have been distinguished in embryonic heart cell cultures: M cells (myoblastlike) and F cells (fibroblast-like). However, by different criteria, more than two cell types have been found in the heart in vivo. In the present study, heart cell types are redefined by properties which can be used for identifying cells both in vitro and in vivo. Trypsin-dissociated cells from 7-day chick hearts were cultured for 24 h. PAS staining indicated that all M (thick, refractile) cells contain glycogen (gly+), while most F (spread) cells do not (gly). Under the electronmicroscope, only gly+ cells contain myofibrils; most of these cells beat spontaneously in culture. Gly cells do not beat. Gly+ cells with myofibrils as well as gly cells are found in the inoculum and in the heart in vivo. The ultrastructure of gly+ cells in vitro and of muscle cells in the myocardium in vivo is similar. Therefore, it is concluded that gly+ cells in culture are derived from the myocardium (muscle) of the heart. Gly cells are apparently derived from the epicardium, the endocardium and the endothelial lining of blood vessels.  相似文献   

17.
18.
The levels and its interindividual and intraindividual variations of selenium (Se) and mercury (Hg) in erythrocytes and plasma were investigated in seven healthy young men during a period of 10 wk, with emphasis on the relationship to the dietary intake of several defined food items. The intraindividual variation, estimated by coefficients of variation (CVs), was 9.9% for plasma Se (PSe), 9.5% for erythrocyte Se (ESe), 42.4% for PHg, and 11.7% for EHg on the average. Significant correlations were found for mean ESe levels in each subject and his fish-eating frequency during this study (r=0.752, p<0.01). Weekly PHg levels were also correlated with average fish-eating frequency in the corresponding week of blood collection (r=0.367, p<0.05). Fish intake within 24 h before blood collection influenced PHg levels significantly.  相似文献   

19.
Dissolved DNA and microbial biomass and activity parameters were measured over a 15-month period at three stations along a salinity gradient in Tampa Bay, Fla. Dissolved DNA showed seasonal variation, with minimal values in December and January and maximal values in summer months (July and August). This pattern of seasonal variation followed that of particulate DNA and water temperature and did not correlate with bacterioplankton (direct counts and [3H]thymidine incorporation) or phytoplankton (chlorophyll a and 14CO2 fixation) biomass and activity. Microautotrophic populations showed maxima in the spring and fall, whereas microheterotrophic activity was greatest in late summer (September). Both autotrophic and heterotrophic microbial activity was greatest at the high estuarine (low salinity) station and lowest at the mouth of the bay (high salinity station), irrespective of season. Dissolved DNA carbon and phosphorus constituted 0.11 ± 0.05% of the dissolved organic carbon and 6.6 ± 6.5% of the dissolved organic phosphorus, respectively. Strong diel periodicity was noted in dissolved DNA and in microbial activity in Bayboro Harbor during the dry season. A noon maximum in primary productivity was followed by an 8 p.m. maximum in heterotrophic activity and a midnight maximum in dissolved DNA. This diel periodicity was less pronounced in the wet season, when microbial parameters were strongly influenced by episodic inputs of freshwater. These results suggest that seasonal and diel production of dissolved DNA is driven by primary production, either through direct DNA release by phytoplankton, or more likely, through growth of bacterioplankton on phytoplankton exudates, followed by excretion and lysis.  相似文献   

20.

Background

Animal models have become valuable experimental tools for understanding the pathophysiology and therapeutic interventions in cardiovascular disease. Yet to date, few studies document the age- and sex-related differences in arterial pressure, circadian rhythm, and renal function in normotensive mice under basal conditions, across the life span. We hypothesized that mice display similar sex- and age-related differences in arterial pressure and renal function to humans.

Methods

Mean arterial pressure (MAP) and circadian rhythm of arterial pressure were measured over 3 days via radiotelemetry, in 3- and 5-month-old (adult) and 14- and 18-month-old (aged) FVB/N and in 5-month-old (adult) C57BL/6 male and female normotensive mice. In FVB/N mice, albuminuria from 24-h urine samples as well as body, heart, and kidney weights were measured at each age.

Results

Twenty-four-hour MAP was greater in males than females at 3, 5, and 14 months of age. A similar sex difference in arterial pressure was observed in C57BL/6 mice at 5 months of age. In FVB/N mice, 24-h MAP increased with age, with females displaying a greater increase between 3 and 18 months of age than males, such that MAP was no longer different between the sexes at 18 months of age. A circadian pattern was observed in arterial pressure, heart rate, and locomotor activity, with values for each greater during the active (night/dark) than the inactive (day/light) period. The night-day dip in MAP was greater in males and increased with age in both sexes. Albuminuria was greater in males than females, increased with age in both sexes, and rose to a greater level in males than females at 18 months of age.

Conclusions

Arterial pressure and albuminuria increase in an age- and sex-specific manner in mice, similar to patterns observed in humans. Thus, mice represent a useful model for studying age and sex differences in the regulation of arterial pressure and renal disease. Understanding the mechanisms that underlie the pathophysiology of cardiovascular disease may lead to new and better-tailored therapies for men and women.
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