Clostridium perfringens Septicemia and a Bleeding Ulcer of a Jejunal Interposition: A Case Report and Short Review of the Literature.

INTRODUCTION: We report a case of Clostridium perfringens septicemia in a patient presenting with a bleeding ulcer of a jejunal interposition. CASE PRESENTATION: An 81-year-old female patient was acutely admitted to our hospital due to hematemesis and melena. She had a history of metastatic gastrointestinal stromal tumor, for which she was receiving second line treatment with sunitinib. She had also undergone a Merendino procedure 4 years prior to presentation. The patient underwent emergency gastroscopy, which revealed a bleeding ulcer in the jejunal interposition. Despite initial endoscopic control of the bleeding and transfusion of blood products, the hemoglobin level continued to drop, and the patient was treated for an assumed hemolytic transfusion reaction. The patient died 3 days following admission, and the results of blood cultures later confirmed a Clostridium perfringens septicemia. The postmortem examination revealed a diffuse spread of Clostridium perfringens to multiple organs. CONCLUSION: This case is a reminder of the importance of considering septicemia, particularly in association with Clostridium perfringens, as a potential cause of hemolysis. It also demonstrates the extent of organ involvement in a case of diffuse clostridial myonecrosis.

Acute alcohol intoxication reduces mortality, inflammatory responses and hepatic injury after haemorrhage and resuscitation in vivo.

BACKGROUND AND PURPOSE: Haemorrhagic shock and resuscitation (H/R) induces hepatic injury, strong inflammatory changes and death. Alcohol intoxication is assumed to worsen pathophysiological derangements after H/R. Here, we studied the effects of acute alcohol intoxication on survival, liver injury and inflammation after H/R, in rats. EXPERIMENTAL APPROACH: Rats were given a single oral dose of ethanol (5 g·kg(-1) , 30%) or saline (control), 12 h before they were haemorrhaged for 60 min and resuscitated (H/R). Sham groups received the same procedures without H/R. Measurements were made 2, 24 and 72 h after resuscitation. Survival was assessed 72 h after H/R. KEY RESULTS: Ethanol increased survival after H/R three-fold and also induced fatty changes in the liver. H/R-induced liver injury was amplified by ethanol at 2 h but inhibited 24 h after H/R. Elevated serum IL-6 levels as well as hepatic IL-6 and TNF-α gene expression 2 h after H/R were reduced by ethanol. Ethanol enhanced serum IL-1ß at 2 h, but did not affect increased hepatic IL-1ß expression at 72 h after H/R. Local inflammatory markers, hepatic infiltration with polymorphonuclear leukocytes and intercellular adhesion molecule 1 expression decreased after ethanol compared with saline, following H/R. Ethanol reduced H/R-induced IκBα activation 2 h after H/R, and NF-κB-dependent gene expression of MMP9. CONCLUSIONS AND IMPLICATIONS: Ethanol reduced H/R-induced mortality at 72 h, accompanied by a suppression of proinflammatory changes after H/R in ethanol-treated animals. Binge-like ethanol exposure modulated the inflammatory response after H/R, an effect that was associated with NF-κB activity.

Leaf phenology, photosynthesis, and the persistence of saplings and shrubs in a mature northern hardwood forest.

We quantified leaf phenologies of saplings and overstory trees of sugar maple (Acer saccharum Marsh.) and American beech (Fagus grandifolia Ehrh.), and the shrub hobblebush viburnum (Viburnum alnifolium Marsh.) in a 72-year-old northern hardwood forest. Seasonal changes in irradiance in the shrub layer, and in the leaf CO(2) exchange of viburnum, and sugar maple and beech saplings were also measured. Leaf expansion occurred earlier in the spring and green leaves were retained later in the autumn in saplings and shrubs than in overstory trees. During the spring light phase (before overstory closure), large CO(2) gains by all three shrub-layer species occurred as a result of a combination of relatively large leaf area, high photosynthetic capacity, and high irradiance. Throughout the summer shade phase, photosynthetic capacity at a given irradiance remained relatively constant, but CO(2) gain was typically limited by low irradiances. Even though irradiance in the shrub layer increased during the autumn light phase as the overstory opened, CO(2) gains were modest compared to springtime values because of declining leaf area and photosynthetic capacity in all three species. The CO(2) gains during the spring light phase, and to a lesser extent during the autumn light phase, may be important to the carbon balance and long-term persistence of saplings and shrubs in the usually light-limited shrub layer of a northern hardwood forest. Therefore, for some late-successional species, leaf phenology may be an important characteristic that permits their long-term persistence in the shrub layer of mature northern hardwood forests.

Picosecond planar laser-induced fluorescence measurements of OH A 2 + ( ' = 2) lifetime and energy transfer in atmospheric pressure flames.

A picosecond, excimer-Raman laser (268 nm, 400 ps FWHM) was used for laser sheet excitation of OH in the (2, 0) band. The fluorescence was detected with a fast-gated, intensified camera (400-ps gate width). The effective collisional lifetime of the spectrally integrated fluorescence was measured in two dimensions by shifting the intensifier gate across the decay curve. The average lifetime is ~2.0 ns for a stoichiometric methane -air flame with spatial variations of +/-10 %. Shorter collisional lifetimes were measured for rich flame conditions that are due to a higher number density of the quenchers. Vibrational energy transfer (VET) was observed in premixed methane -air and methane -oxygen flames by putting the fast-gated camera behind a spectrometer. The spectrum of the methane -air flame shows strong VET in contrast with the methane -oxygen flame. This is because N2 is a weak electronic quencher but a strong VET agent. By fitting the measured time dependence of the different vibrational populations ( ' = 2, 1, 0) to a four-level model, rate constants for quenching and VET were determined. For the lower states ( ' = 0, 1) our results are in good agreement with literature values. For a prediction of a spectrally integrated, collisional lifetime in a known collisional environment it is important to consider not only the quenching but also the amount of energy transfer in the excited state as well as the spectral detection sensitivity.

Picosecond laser-induced fluorescence measurement of rotational energy transfer of OH A (2)?(+) (v? = 2) in atmospheric pressure flames.

Rate constants for total and state-specific rotational energy transfer (RET) of OH A(2) ?(+) (v? = 2) have been measured directly in atmospheric methane-air and methane-oxygen flames for the first time to our knowledge. We used a picosecond Raman-excimer laser (tau(l) = 300 ps, lambda = 268 nm) to excite the P(11) (12.5) and Q(11) (16.5) A -X transitions in the (2, 0) band of OH molecules. We analyzed the resultant fluorescence with a high-resolution spectrometer in combination with a fast-gated, intensified CCD camera (tau(g) = 400 ps). We recorded the temporal evolution of the emission spectrum by shifting the detection time with respect to the laser pulse. Measured emission spectra were inverted to yield the time-dependent population of rotational levels in the excited state. We calculated rate constants for RET from the results of the fit. The total RET in v? = 2 is similar to v? = 0, 1. The state-specific rates are represented well by a simple energy-gap law.

Autumnal leaf conductance and apparent photosynthesis by saplings and sprouts in a recently disturbed northern hardwood forest.

Leaf surface conductance and apparent photosynthesis were measured during late summer and autumn on saplings and sprouts of pin cherry (Prunus pensylvanica), yellow birch (Betula alleghaniensis), American beech (Fagus grandifolia), and sugar maple (Acer saccharum) naturally revegetating a site in the northern hardwood forest 5 years following a commercial whole-tree harvest. Prior to the disturbance (i.e., the harvest) the site was codominated by American beech, sugar maple, and yellow birch, whereas after the disturbance pin cherry was the dominant species. Conductance and photosynthetic rate of pin cherry leaves were comparatively high while those of American beech and sugar maple were low. Pin cherry retained green, physiologically active leaves longer into autumn than American beech and sugar maple. The rates and seasonal duration of leaf gas exchange on the disturbed site were therefore greater than they would have been had the site not become dominated by pin cherry.

Transport and loss of nitrous oxide in soil water after forest clear-cutting.

Whole-tree harvesting increased the concentration of nitrous oxide dissolved in soil water by two orders of magnitude over the concentration expected in equilibrium with the atmosphere. In contrast, the nitrous oxide content of soil water in an intact, second-growth forest was close to the expected theoretical value. Nitrous oxide, produced at active sites in the soil, dissolves in soil water and is transported to seeps and streams where it rapidly degasses from the solution and is released into the atmosphere. This loss of nitrous oxide after clear-cutting is not important to the nitrogen economy of the site; however, it may be important to the global atmospheric budget of nitrous oxide. Sources of nitrous oxide may have been overlooked because nitrous oxide emissions can be separated in time and space from the sites of the most intense production of nitrous oxide.

Phosphorus cycling in a northern hardwood forest: biological and chemical control.

Phosphorus is tightly conserved within the northern hardwood forest ecosystems at Hubbard Brook, New Hampshire. Detailed analyses of the soil system indicate that biological and geochemical processes, stratified within the profile, regulate phosphorus retention.

Natural disturbance and the steady state in high-altitude balsam fir forests.

Wind-induced, cyclic waves of death, regeneration, and maturation constantly move through the high-altitude balsam fir forests in the northeastern United States. Biomass and productivity relations, species diversity, and nutrient cycling patterns are closely tied to this cycle of disturbance. Disturbance is thus an integral part of the long-term maintenance of this ecosystem. Since forests of this type normally include all phases of the disturbance-regeneration cycle, they may constitute a steady-state ecosystem in equilibrium with the surrounding environment.

Nitrogen budget for an aggrading northern hardwood forest ecosystem.

Long-term analyses of the structure and function of a northern hardwood ecosystem have resulted in measurement of the salient features of the nitrogen cycle. These data allow an evaluation of the importance of the various components and provide a framework for more efficient forest management.

Role of Erythronium americanum Ker. in Energy Flow and Nutrient Dynamics of a Northern Hardwood Forest Ecosystem.

The aboveground activity of the spring herb, Erythronium americanum, is restricted to the period between snowmelt and forest canopy development. Its phenology and production capacity closely adapt the species to this temporal niche in northern deciduous forests. While E. americanum has a minor effect on energy flow, it may reduce losses of potassium and nitrogen from the ecosystem during the period of maximum removal by incorporating these elements in accumulating biomass. Later, during the summer, these nutrients are made available when the above-ground, nonperennating tissues decay.

Organic matter and nutrient dynamics of the forest and forest floor in the Hubbard Brook forest.

The forest floor is a major reservoir of organic matter and nutrients for the ecosystem and as such it influences or regulates most of the functional processes occurring throughout the ecosystem. This study reports on the nutrient and organic matter content of the forest floor of the Hubbard Brook Experimental Forest during different seasons and attempts to correlate results from studies of vegetation, litter, decomposition, stemflow, throughfall, and soil. An organic matter budget is presented for an undisturbed watershed.Average weight of the forest floor on an undisturbed watershed ranged from 25,500 to 85,500 kg/ha. The weighted watershed average was 46,800 kg/ha. Although the F and H horizons did not vary significantly with time, the L horizon increased significantly during the period June to August largely as a result of a severe hail storm. The order of abundance of elements in the forest floor was Nτ;Ca≷Fe>S>P>Mn>K>Mg>Na>Zn>Cu. The concentrations of Ca, K, and Mn decreased with depth in the forest floor while N, P, S, Na, Fe, Zn, and Cu concentrations increased. N:P ratios were similar in decomposing leaf tissue, the forest floor, litterfall, and net stemflow plus throughfall suggesting a similar pattern of cycling. S was proportional to N and P in decomposing leaf tissue, the forest floor, and litterfall. Net stemflow and throughfall were affected by a relatively large input of SO4=-S from the atmosphere. Residence times for elements in the forest floor were affected by inputs other than litterfall (precipitation, stemflow, and throughfall). Calculation of residence times using all inputs caused smaller values than if litterfall alone was used. While all residence times were reduced, the major differences occurred for K, S, and Na. N and P showed relatively long residence times as a result of retranslocation and immobilization by decomposers. The slow turnover rate because of the strong demand and retention by all biota must account for the efficiency of the intrasystem cycling process for N and P. K showed the shortest residence time. A rapid and efficient uptake of K by vegetation seems to account for the efficient cycling of this element. The patterns of nutrient cycling are several depending on the chemical properties of the forest floor, and nutritional requirements of the biota.

Acid rain: a serious regional environmental problem.

At present, acid rain or snow is falling on most of the northeastern United States. The annual acidity value averages about pH 4, but values between pH 2.1 and 5 have been recorded for individual storms. The acidity of precipitation in this region apparently increased about 20 years ago, and the increase may have been associated with the augmented use of natural gas and with the installation of particle-removal devices in tall smokestacks. Only some of the ecological and economic effects of this widespread introduction of strong acids into natural systems are known at present, but clearly they must be considered in proposals for new energy sources and in the development of air quality emission standards.

Barrier island forest ecosystem: role of meteorologic nutrient inputs.

The Sunken Forest, located on Fire Island, a barrier island in the Atlantic Ocean off Long Island, New York, is an ecosystem in which most of the basic cation input is in the form of salt spray. This meteorologic input is sufficient to compensate for the lack of certain nutrients in the highly weathered sandy soils. In other ecosystems these nutrients are generally supplied by weathering of soil particles. The compensatory effect of meteorologic input allows for primary production rates in the Sunken Forest similar to those of inland temperate forests.

Revegetation following Forest Cutting: Mechanisms for Return to Steady-State Nutrient Cycling.

Dense stands of a woody, successional species, Prunus pensylvanica L., develop rapidly, with early closure of canopy and rapid attainment of high values of net annual production and nutrient accumulation. Such rapid growth following disturbance tends to minimize losses of nutrients from the ecosystem, thus promoting a return to steady-state cycling characteristic of a mature forest.