Timing and magnitude of C partitioning through a young loblolly pine (Pinus taeda L.) stand using 13C labeling and shade treatments.

The dynamics of rapid changes in carbon (C) partitioning within forest ecosystems are not well understood, which limits improvement of mechanistic models of C cycling. Our objective was to inform model processes by describing relationships between C partitioning and accessible environmental or physiological measurements, with a special emphasis on short-term C flux through a forest ecosystem. We exposed eight 7-year-old loblolly pine (Pinus taeda L.) trees to air enriched with (13)CO(2) and then implemented adjacent light shade (LS) and heavy shade (HS) treatments in order to manipulate C uptake and flux. The impacts of shading on photosynthesis, plant water potential, sap flow, basal area growth, root growth and soil CO(2) efflux rate (CER) were assessed for each tree over a 3-week period. The progression of the (13)C label was concurrently tracked from the atmosphere through foliage, phloem, roots and surface soil CO(2) efflux. The HS treatment significantly reduced C uptake, sap flow, stem growth and fine root standing crop, and resulted in greater residual soil water content to 1 m depth. Soil CER was strongly correlated with sap flow on the previous day, but not the current day, with no apparent treatment effect on the relationship. Although there were apparent reductions in new C flux belowground, the HS treatment did not noticeably reduce the magnitude of belowground autotrophic and heterotrophic respiration based on surface soil CER, which was overwhelmingly driven by soil temperature and moisture. The (13)C label was immediately detected in foliage on label day (half-life = 0.5 day), progressed through phloem by Day 2 (half-life = 4.7 days), roots by Days 2-4, and subsequently was evident as respiratory release from soil which peaked between Days 3 and 6. The δ(13)C of soil CO(2) efflux was strongly correlated with phloem δ(13)C on the previous day, or 2 days earlier. While the (13)C label was readily tracked through the ecosystem, the fate of root C through respiratory, mycorrhizal or exudative release pathways was not assessed. These data detail the timing and relative magnitude of C flux through various components of a young pine stand in relation to environmental conditions.

Contribution of inappropriate complementary foods to the salt intake of 8-month-old infants.

BACKGROUND/OBJECTIVE: Complementary feeding is a critical developmental time for establishing variety, and appropriate feeding practices are important. These include recommendations for a maximum intake of sodium (salt), because of the potential harmful effect of excessive intake on the developing kidneys and blood pressure in later life. Sodium intakes were examined to establish, if inappropriate complementary feeding practices were contributing to high intakes. SUBJECTS/METHODS: Data were collected from a cohort of 1178 8-month-old infants born in 1991/92, participating in the Avon Longitudinal Study of Parents and Children, using a 3-day dietary records completed by their mothers. Sodium and energy intakes were calculated and infants were categorised into quartiles of sodium intake. RESULTS: Majority of infants were first introduced to solids around 3-4 months, with plain baby rice, rusks and other cereals being the first foods consumed during complementary feeding. In the whole sample, 70% consumed in excess, of 400 mg sodium per day, the maximum UK recommendation for children up to age 12 months. The mean sodium intake for the highest quartile was 1060 mg per day. Infants in this quartile were often consuming cows' milk as a main drink; eating three times the amount of bread compared with the lowest quartile and used salty flavourings such as yeast extract and gravy. CONCLUSIONS: Sodium intakes in this cohort of infants were higher than recommendations. Clear and practical education is needed on complementary feeding practice for mothers highlighting what foods to introduce and when. Manufacturers have a responsibility to reduce the sodium content of food products.

Average Soil Water Retention Curves Measured by Neutron Radiography.

Water retention curves are essential for understanding the hydrologic behavior of partially saturated porous media and modeling flow and transport processes within the vadose zone. We directly measured the main drying and wetting branches of the average water retention function obtained using two-dimensional neutron radiography. Flint sand columns were saturated with water and then drained and rewetted under quasi-equilibrium conditions using a hanging water column setup. Digital images (2048 by 2048 pixels) of the transmitted flux of neutrons were acquired at each imposed matric potential (∼10-15 matric potential values per experiment) at the National Institute of Standards and Technology Center for Neutron Research BT-2 neutron imaging beam line. Volumetric water contents were calculated on a pixel-by-pixel basis using Beer-Lambert's law after taking into account beam hardening and geometric corrections. To account for silica attenuation and remove scattering effects at high water contents, the volumetric water contents were normalized (to give relative saturations) by dividing the drying and wetting sequences of images by the images obtained at saturation and satiation, respectively. The resulting pixel values were then averaged and combined with information on the imposed basal matric potentials to give average water retention curves. The average relative saturations obtained by neutron radiography showed an approximate one-to-one relationship with the average values measured volumetrically using the hanging water column setup. There were no significant differences (P < 0.05) between the parameters of the van Genuchten equation fitted to the average neutron radiography data and those estimated from replicated hanging water column data. Our results indicate that neutron imaging is a very effective tool for quantifying the average water retention curve.

Analysis of ergosterol for the detection of mold in soils by automated on-fiber derivatization headspace extraction-SPME-GC/MS.

The estimate of ergosterol ([5,7,22-ergostatrien-3beta-ol] has been used by many to relate its concentration to the amount of mold in soils. This new method using on-fiber derivatization-solid phase microextraction-GC/MS method for the analysis of ergosterol presents a quick and straightforward method where low detection limits (1.5 ppb) and good limit of quantitation range (3 ppb to 90 ppm) can be achieved with careful control of analytical parameters. After saponification of real soil samples, sampling without extensive workup can be performed and analysis by a standard addition method can be utilized to deduce the original sample concentration of ergosterol. Peak area extraction analysis by MS SIM on selected characteristic fragment ions gives results with RSD < or = 2.2%.

The impact of a child obesity treatment intervention on parent child-feeding practices.

BACKGROUND: Effective treatment of childhood obesity requires a multi-factorial approach and should target factors impacting on a child's environment. OBJECTIVE: To explore the impact of three treatment programs on parental child-feeding practices at 6, 12 and 24 months post-program. SUBJECTS/INTERVENTION: Overweight children (n=159) aged 5-7 years, recruited to the Hunter Illawarra Kids Challenge Using Parent Support (HIKCUPS) randomized controlled trial with three treatment arms; a dietary modification program, a physical activity skill development program or a combination of both programs. Main outcome measures. The Child Feeding Questionnaire (CFQ), a validated 31-item questionnaire measuring child-feeding practices, completed by parents. Statistical analysis. Linear mixed models were used to assess change over time and to determine differences by intervention group. RESULTS: A significant decrease (p<0.01) in CFQ domain scores were reported and sustained at 24 months for all groups, in the domain of pressure to eat (mean+/-SEM, 1.8+/-0.06, 1.6+/-0.06) with increases in degree of monitoring (4.0+/-0.07, 4.2+/-0.06). The domain of restriction showed significant decreases in dietary intervention groups only (baseline 3.9+/-0.05, 24 months 3.7+/-0.06), the domain scores for concern were found to be strongly associated with child BMI z-score (r=0.73, p < 0.001) at baseline only. CONCLUSIONS: This study provides evidence that specific child-feeding domains are modifiable in the context of a targeted obesity intervention and further that changes can be sustained over time. HIKCUPS study: National Centre for Clinical Trials (NCT): 00107692 clinicaltrials.gov Identifier: NCT00107692 http://clinicaltrials.gov/ct2/home.

Impact of a child obesity intervention on dietary intake and behaviors.

OBJECTIVE: The aims of this study were to describe the dietary intakes and food behavior changes of overweight and obese children participating in the Hunter Illawarra Kids Challenge Using Parent Support (HIKCUPS) study and to describe the impact of a best practice dietary modification program. DESIGN: A multicenter randomized controlled trial with allocation to one of three intervention arms: (1) parent-centered nutrition lifestyle program; (2) child-centered physical activity skill development program; or (3) both the programs. PARTICIPANTS: One hundred and sixty-five overweight, pre-pubertal children 5-9 years of age (58% female). MEASUREMENTS: Dietary intake was assessed at baseline, 6 and 12 months post-commencement of the program using a semiquantitative food frequency questionnaire. RESULTS: After 6 and 12 months, all groups improved their dietary intake, with no differences detected between groups (P>0.05). Total quantity of food (g) and kJ kg(-1) decreased significantly at both time points (P<0.05). Percent energy derived from core food groups, except fruit, increased significantly at 12 months compared to baseline (P<0.05), and non-core foods decreased, with the largest decreases being for sweetened drinks (5.0+/-0.4 vs 2.9+/-0.3% of energy baseline to 12 months, P<0.001) and packaged lunch box snacks (5.4+/-0.3 vs 4.1+/-0.3% of energy baseline to 12 months, P<0.001). CONCLUSION: All treatment groups in the HIKCUPS study appear to be equally efficacious in improving dietary intake in overweight and obese children.

Dynamics of water transport and storage in conifers studied with deuterium and heat tracing techniques.

The volume and complexity of their vascular systems make the dynamics of long-distance water transport in large trees difficult to study. We used heat and deuterated water (D2)) as tracers to characterize whole-tree water transport and storage properties in individual trees belonging to the coniferous species Pseudotsuga menziesii (Mirb.) Franco and Tsuga heterophylla (Raf.) Sarg. The trees used in this study spanned a broad range of height (13.5-58 m) and diameter (0.14-1.43 m). Sap flow was monitored continuously with heat dissipation probes near the base of the trunk prior to, during and following injection of D2O. The transit time for D2O transport from the base of the trunk to the upper crown and the tracer residence time were determined by measuring hydrogen isotope ratios in water extracted from leaves sampled at regular intervals. Transit times for arrival of D2O in the upper crown ranged from 2.5 to 21 d and residence times ranged from 36 to 79 d. Estimates of maximum sap velocity derived from tracer transit times and path length ranged from 2.4 to 5.4 m d(-1). Tracer residence time and half-life increased as tree diameter increased, independent of species. Species-independent scaling of tracer velocity with sapwood-specific conductivity was also observed. When data from this study were combined with similar data from an earlier study of four tropical angiosperm trees, species-independent scaling of tracer velocity and residence time with sapwood hydraulic capacitance was observed. Sapwood capacitance is an intrinsic tissue-level property that appears to govern whole-tree water transport in a similar manner among both tracheid- and vessel-bearing species.

Native root xylem embolism and stomatal closure in stands of Douglas-fir and ponderosa pine: mitigation by hydraulic redistribution.

Hydraulic redistribution (HR), the passive movement of water via roots from moist to drier portions of the soil, occurs in many ecosystems, influencing both plant and ecosystem-water use. We examined the effects of HR on root hydraulic functioning during drought in young and old-growth Douglas-fir [ Pseudotsuga menziesii (Mirb.) Franco] and ponderosa pine ( Pinus ponderosa Dougl. Ex Laws) trees growing in four sites. During the 2002 growing season, in situ xylem embolism, water deficit and xylem vulnerability to embolism were measured on medium roots (2-4-mm diameter) collected at 20-30 cm depth. Soil water content and water potentials were monitored concurrently to determine the extent of HR. Additionally, the water potential and stomatal conductance ( g(s)) of upper canopy leaves were measured throughout the growing season. In the site with young Douglas-fir trees, root embolism increased from 20 to 55 percent loss of conductivity (PLC) as the dry season progressed. In young ponderosa pine, root embolism increased from 45 to 75 PLC. In contrast, roots of old-growth Douglas-fir and ponderosa pine trees never experienced more than 30 and 40 PLC, respectively. HR kept soil water potential at 20-30 cm depth above -0.5 MPa in the old-growth Douglas-fir site and -1.8 MPa in the old-growth ponderosa pine site, which significantly reduced loss of shallow root function. In the young ponderosa pine stand, where little HR occurred, the water potential in the upper soil layers fell to about -2.8 MPa, which severely impaired root functioning and limited recovery when the fall rains returned. In both species, daily maximum g(s) decreased linearly with increasing root PLC, suggesting that root xylem embolism acted in concert with stomata to limit water loss, thereby maintaining minimum leaf water potential above critical values. HR appears to be an important mechanism for maintaining shallow root function during drought and preventing total stomatal closure.

Converging patterns of uptake and hydraulic redistribution of soil water in contrasting woody vegetation types.

We used concurrent measurements of soil water content and soil water potential (Psi(soil)) to assess the effects of Psi(soil) on uptake and hydraulic redistribution (HR) of soil water by roots during seasonal drought cycles at six sites characterized by differences in the types and amounts of woody vegetation and in climate. The six sites included a semi-arid old-growth ponderosa pine (Pinus ponderosa Dougl. ex P. Laws & C. Laws) forest, a moist old-growth Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) forest, a 24-year-old Douglas-fir forest and three Brazilian savanna sites differing in tree density. At all of the sites, HR was confined largely to the upper 60 cm of soil. There was a common threshold relationship between the relative magnitude of HR and Psi(soil) among the six study sites. Below a threshold Psi(soil) of about -0.4 MPa, overnight recharge of soil water storage increased sharply, and reached a maximum value of 80-90% over a range of Psi(soil) from ~ -1.2 to -1.5 MPa. Although amounts of water hydraulically redistributed to the upper 60 cm of soil were relatively small (0 to 0.4 mm day(-1)), they greatly reduced the rates of seasonal decline in Psi(soil). The effectiveness of HR in delaying soil drying diminished with increasing sapwood area per ground area. The relationship between soil water utilization and Psi(soil) in the 20-60-cm layer was nearly identical for all six sites. Soil water utilization varied with a surrogate measure of rhizosphere conductance in a similar manner at all six sites. The similarities in relationships between Psi(soil) and HR, soil water utilization and relative rhizosphere conductance among the six sites, suggests that, despite probable differences in maximum rooting depth and density, there was a convergence in biophysical controls on soil water utilization and redistribution in the upper soil layers where the density of finer roots is greatest.

Contrasting effects of t10,c12- and c9,t11-conjugated linoleic acid isomers on the fatty acid profiles of mouse liver lipids.

The purpose of this study was to examine the effects of two purified isomers of CLA (c9,t11-CLA and t10,c12-CLA) on the weights and FA compositions of hepatic TG, phospholipids, cholesterol esters, and FFA. Eight-week-old female mice (n = 6/group) were fed either a control diet or diets supplemented with 0.5% c9,t11-CLA or t10,c12-CLA isomers for 8 wk. Weights of liver total lipids and those of individual lipid fractions did not differ between the control and the c9,t11-CLA groups. Livers from animals fed the t10, c12-CLA diet contained four times more lipids than those of the control group; this was mainly due to an increase in the TG fractions (fivefold), but cholesterol (threefold), cholesterol esters (threefold), and FFA (twofold) were also significantly increased. Although c9,t11-CLA did not significantly alter the weights of liver lipids when compared with the control group, its intake was associated with significant reductions in the weight percentage (wt% of total FAME) of 18:1n-9 and 18:1n-7 in the TG fraction and with significant increases in the weight percentage of 18:2n-6 in the TG, cholesterol ester, and phospholipid fractions. On the other hand, t10,c12-CLA intake was linked with a significant increase in the weight percentage of 18:1n-9 and a decrease in that of 18:2n-6 in all lipid fractions. These changes may be the result of alterations in the activity of delta9-desaturase (stearoyl CoA desaturase) and the enzymes involved in the metabolism of 18:2n-6. Thus, the two isomers differed not only in their effects on the weights of total liver lipids and lipid fractions but also on the FA profile of the lipid fractions.

Evaluation of a pilot school programme aimed at the prevention of obesity in children.

This paper describes the development, implementation and evaluation of a school- and family-based intervention to prevent obesity in children aged 5-7 years. In addition, the efficacy of three different intervention programmes was compared. Children aged 5-7 years (n=213) were recruited from three primary schools in Oxford and randomly allocated to a control group or one of three intervention groups: nutrition group, physical activity group, and combined nutrition and physical activity group. The setting for the interventions was lunchtime clubs, where an interactive and age-appropriate nutrition and/or physical activity curriculum was delivered. The intervention lasted for 20 weeks over four school terms (approximately 14 months). Children's growth, nutrition knowledge, diet and physical activity were assessed at baseline and at the end of the intervention. Significant improvements in nutrition knowledge were seen in all children (p<0.01) between baseline and post-intervention, and results were highly significant in the nutrition and combined group (p<0.001). Overall, fruit and vegetable intake increased significantly (p<0.01 and <0.05, respectively), with changes seen in fruit consumption in the nutrition group (p<0.05) and the control group (p<0.05) in particular. No significant changes in the rates of overweight and obesity were seen as a result of the intervention. Gender differences were not detected in the majority of assessments and there was no clear effect of programme type per se. This pilot study has demonstrated that school may be a suitable setting for the promotion of healthy lifestyles in children, but requires replication in other social settings. Future initiatives should be long-lasting, multi-faceted and sustainable, involving all children in a school, and should target the whole environment and be behaviourally focused. The ultimate goal of any such programme is to lead to positive behaviour change which will have a beneficial effect on long-term health. Successful targeting of the family remains a challenge to such interventions.

Trans-10,cis-12 CLA increases liver and decreases adipose tissue lipids in mice: possible roles of specific lipid metabolism genes.

Although consumption of CLA mixtures has been associated with several health effects, less is known about the actions of specific CLA isomers. There is evidence that the t10,c12-CLA isomer is associated with alterations in body and organ weights in animals fed CLA, but the mechanisms leading to these changes are unclear. The purpose of this study was to determine the effects of two commonly occurring isomers of CLA on body composition and the transcription of genes associated with lipid metabolism. Eight-week-old female mice (n = 11 or 12/group) were fed either a control diet or diets supplemented with 0.5% c9,t11-CLA or t10,c12-CLA isomers or 0.2% of the peroxisome proliferator-activated receptor alpha (PPARalpha) agonist fenofibrate for 8 wk. Body and retroperitoneal adipose tissue weights were significantly lower (6-10 and 50%, respectively), and liver weights were significantly greater (100%) in the t10,c12-CLA and the fenofibrate groups compared with those in the control group; body and tissue weights in the c9,t11-CLA group did not differ from those in the control group. Livers from animals in the t10,c12-CLA group contained five times more lipids than in the control group, whereas the lipid content of the fenofibrate group did not differ from that in the control group. Although fenofibrate increased the mRNA for PPARalpha, t10,c12-CLA decreased it. These results suggest that PPARalpha did not mediate the effects of t10,c12-CLA on body composition. The CLA isomers and fenofibrate altered mRNA levels for several proteins involved in lipid metabolism, but the most striking difference was the reduction of mRNA for leptin and adiponectin in the t10,c12-CLA group. These initial results suggest that changes associated with energy homeostasis and insulin action may mediate the effects of t10,c12-CLA on lipid metabolism.

Similar effects of c9,t11-CLA and t10,c12-CLA on immune cell functions in mice.

Published results regarding the effects of CLA on immune cell functions have ranged from stimulation to inhibition. In those studies, a mixture of CLA isomers were used, and food intake was not controlled. We have examined whether the discrepancies in the results of earlier studies may be due to the lack of controlled feeding and whether the two isomers of CLA may differ in their effects on immune cell functions. Three groups of C57BL/6 female mice were fed either a control, c9,t11-CLA-, or t10,c12-CLA (0.5 wt%)-supplemented diet, 5 g/d, for 56 d. At the end of the study, the number of immune cells in spleens, bone marrows, or in circulation; proliferation of splenocytes in response to T and B cell mitogens; and prostaglandin secretion in vitro did not differ among the three groups. Both CLA isomers significantly increased in vitro tumor necrosis factor alpha and interleukin (IL)-6 secretion and decreased IL-4 secretion by splenocytes compared to those in the control group. Thus, the two CLA isomers had similar effects on all response variables tested. The discrepancies among the results from previous studies did not seem to be caused by the differences in the isomer composition of CLA used.

Treadmill exercise training blunts suppression of splenic natural killer cell cytolysis after footshock.

This study extended to treadmill exercise training our prior report (Dishman RK, Warren JM, Youngstedt SD, Yoo H, Bunnell BN, Mougey EH, Meyerhoff JL, Jaso-Friedmann L, and Evans DL. J Appl Physiol 78: 1547-1554, 1995) that activity wheel running abolished the suppression of footshock-induced natural killer (NK) cell cytolysis. Twenty-four male Fischer 344 rats were assigned to one of three groups (n = 8, all groups): 1) a home-cage control group, 2) a sedentary treatment group, or 3) a treadmill-running group (0 degrees incline, 25 m/min, 35 min/day, 6 days/wk). After 6 wk, the treadmill and sedentary groups received 2 days of footshock. Splenic NK cytotoxicity was determined by standard 4-h (51)Cr release assay. Percentages of lymphocytes were determined by flow cytometry. Plasma levels of ACTH, corticosterone, and prolactin concentration were measured by radioimmunoassay. After footshock, percentage of lysis relative to home-cage controls was 40% and 80% for sedentary and treadmill-trained animals, respectively (P < 0.05). Our results indicate that the protective effect of chronic exercise on innate cellular immunity in the Fischer 344 male rat is not restricted to activity wheel running, nor is it explained by elevations in basal NK activity, increased percentages of splenic NK and cytotoxic T cells, or increased plasma levels of ACTH, corticosterone, and prolactin.

Characteristics of the muscularis mucosae in the acid-secreting region of the rabbit stomach.

It has been suggested that muscularis mucosae excitation may augment gastric acid secretion, implying that this muscle should contract to secretagogues or stimulation of its motor innervation. The aim of this study was to characterize in vitro the responses of the muscularis mucosae in the rabbit gastric corpus to substances that modulate acid release and to intrinsic nerve stimulation. Muscularis mucosae from both fundic and antral ends of the corpus had identical mechanical properties, contracted to ACh, ADP, ATP, and histamine but relaxed to vasoactive intestinal polypeptide. Fundic but not antral muscularis mucosae contracted to bombesin and PGE2 and PGF2alpha, whereas adenosine, AMP, CCK, gastrin, secretin, and somatostatin were without effect on any preparation. In both regions electrical field stimulation evoked TTX-sensitive responses consisting of an atropine-resistant contraction followed by an NG-nitro-L-arginine methyl ester- and indomethacin-resistant relaxation. It is concluded from the regional variability in the pharmacological properties of the gastric muscularis mucosae that if its motor activity is linked to acid secretion this would be achieved by a neurally mediated relaxation rather than a paracrine- and/or endocrine-induced alteration in tone.

Activity-wheel running attenuates suppression of natural killer cell activity after footshock.

We studied whether voluntary running in an activity wheel moderates splenic natural killer (NK) cell cytotoxicity after footshock. Young (50-day) male Fischer 344 rats were randomly assigned to 1) sedentary (n = 16) or 2) activity-wheel (n = 16) groups that each received controllable or uncontrollable footshock on 2 consecutive days or 3) a sedentary home-cage control group (n = 8). Spleens and trunk blood were collected 30 min after the second footshock session. Cytotoxicity was determined by a standard 4-h 51Cr release assay. Percentages of OX6+ (B), OX8+ [T suppressor/cytotoxic (Ts/c)], W3/25+ (T helper), Thy-1.1 (Pan T cell marker), and 5C6+ (NK) cells were determined by flow cytometry. Plasma adrenocorticotropic hormone, corticosterone, and prolactin concentrations were measured by radioimmunoassay as modulators of NK activity. Percentage of specific lysis after footshock was approximately 52% of control values for sedentary animals compared with approximately 96% of control values for activity-wheel animals. The groups did not differ in percentages of NK or Ts/c cells. We conclude that voluntary activity-wheel running protects against the suppression of splenic NK activity induced by footshock. This protective effect of wheel running is not explained by an elevation in baseline NK activity; increased percentages of splenic NK or Ts/c cells; or plasma levels of adrenocorticotropic hormone, corticosterone, and prolactin.

Rationing health care resources. Is the quality-adjusted life-year a helpful guide?

The quality-adjusted life-year, an economic tool for allocating health care resources, lets researchers compare the cost-effectiveness of different therapies for virtually any disease. It purports to describe quantity of life, with an adjustment for quality of life, as a function of financial cost. Its goal is to maximize health care efficiency, but its methodology does not adequately meet the needs of older patients.

Pulmonary function after laparoscopic cholecystectomy.

BACKGROUND: The purpose of this study was to prospectively compare the effect of laparoscopic cholecystectomy (LC) versus open cholecystectomy (OC) on postoperative pulmonary function. METHODS: Forty consecutive patients (20 in each group) who were evenly matched in terms of pulmonary risk factors were assigned to either elective LC or OC. Pulmonary function studies, oxygen saturation, and chest radiography were performed on both groups before and after the operation until baseline levels were reached. Narcotic requirements and pulmonary complications were compared. The t test, ANOVA, and chi-squared analysis were used. RESULTS: Compared to the patients who underwent OC, patients who underwent LC had a significant reduction in postoperative pulmonary impairment (30% to 38%) in all areas studied including forced vital capacity; forced expiratory volume in 1 second; forced expiratory flow, mid-expiratory phase; maximum forced expiratory flow; maximum voluntary ventilation; total lung capacity; and oxygen saturation. Pulmonary function returned to baseline levels 4 to 10 days sooner after LC. Pulmonary complications including atelectasis and hypoxia were less frequent after LC. An eight-fold decrease was noted in postoperative pain medication requirement in the LC group. CONCLUSIONS: Compared to OC, laparoscopic cholecystectomy results in a significantly reduced compromise in pulmonary function and narcotic requirement leading to fewer postoperative pulmonary complications. Laparoscopic cholecystectomy should be considered the procedure of choice for elective cholecystectomy.