Light compensation points in shade-grown seedlings of deciduous broadleaf tree species with different successional traits raised under elevated CO2.

We measured leaf photosynthetic traits in shade-grown seedlings of four tree species native to northern Japan, raised under an elevated CO2 condition, to investigate the effects of elevated CO2 on shade tolerance of deciduous broadleaf tree species with different successional traits. We considered Betula platyphylla var. japonica and Betula maximowicziana as pioneer species, Quercus mongolica var. crispula as a mid-successional species, and Acer mono as a climax species. The plants were grown under shade conditions (10% of full sunlight) in a CO2 -regulated phytotron. Light compensation points (LCPs) decreased in all tree species when grown under elevated CO2 (720 µmol·mol(-1) ), which were accompanied by higher apparent quantum yields but no photosynthetic down-regulation. LCPs in Q. mongolica and A. mono grown under elevated CO2 were lower than those in the two pioneer birch species. The LCP in Q. mongolica seedlings was not different from that of A. mono in each CO2 treatment. However, lower dark respiration rates were observed in A. mono than in Q. mongolica, suggesting higher shade tolerance in A. mono as a climax species in relation to carbon loss at night. Thus, elevated CO2 may have enhanced shade tolerance by lowering LCPs in all species, but the ranking of shade tolerance related to successional traits did not change among species under elevated CO2 , i.e. the highest shade tolerance was observed in the climax species (A. mono), followed by a gap-dependent species (Q. mongolica), while lower shade tolerance was observed in the pioneer species (B. platyphylla and B. maximowicziana).

Canopy-level stomatal narrowing in adult Fagus sylvatica under O3 stress - means of preventing enhanced O3 uptake under high O3 exposure?

Spatio-temporally consistent O(3) doses are demonstrated in adult Fagus sylvatica from the Kranzberg Forest free-air fumigation experiment, covering cross-canopy and whole-seasonal scopes through sap flow measurement. Given O(3)-driven closure of stomata, we hypothesized enhanced whole-tree level O(3) influx to be prevented under enhanced O(3) exposure. Although foliage transpiration rate was lowered under twice-ambient O(3) around noon by 30% along with canopy conductance, the hypothesis was falsified, as O(3) influx was raised by 25%. Nevertheless, the twice-ambient/ambient ratio of O(3) uptake was smaller by about 20% than that of O(3) exposure, suggesting stomatal limitation of uptake. The O(3) response was traceable from leaves across branches to the canopy, where peak transpiration rates resembled those of shade rather than sun branches. Rainy/overcast-day and nightly O(3) uptake is quantified and discussed. Whole-seasonal canopy-level validation of modelled with sap flow-derived O(3) flux becomes available in assessing O(3) risk for forest trees.

Enhanced ozone strongly reduces carbon sink strength of adult beech (Fagus sylvatica)--resume from the free-air fumigation study at Kranzberg Forest.

Ground-level ozone (O(3)) has gained awareness as an agent of climate change. In this respect, key results are comprehended from a unique 8-year free-air O(3)-fumigation experiment, conducted on adult beech (Fagus sylvatica) at Kranzberg Forest (Germany). A novel canopy O(3) exposure methodology was employed that allowed whole-tree assessment in situ under twice-ambient O(3) levels. Elevated O(3) significantly weakened the C sink strength of the tree-soil system as evidenced by lowered photosynthesis and 44% reduction in whole-stem growth, but increased soil respiration. Associated effects in leaves and roots at the gene, cell and organ level varied from year to year, with drought being a crucial determinant of O(3) responsiveness. Regarding adult individuals of a late-successional tree species, empirical proof is provided first time in relation to recent modelling predictions that enhanced ground-level O(3) can substantially mitigate the C sequestration of forests in view of climate change.

Circumvention of over-excitation of PSII by maintaining electron transport rate in leaves of four cotton genotypes developed under long-term drought.

We investigated the patterns of response to a long-term drought in the field in cotton cultivars (genotypes) with known differences in their drought tolerance. Four cotton genotypes with varying physiological and morphological traits, suited to different cropping conditions, were grown in the field and subjected to a long-term moderate drought. In general, cotton leaves developed under drought had significantly higher area-based leaf nitrogen content (N (area)) than those under well irrigation. Droughted plants showed a lower light-saturated net photosynthetic rate (A (sat)) with lower stomatal conductance (g (s)) and intercellular CO (2) concentration (C (i)) than irrigated ones. Based on the responses of A (sat) to g (s) and C (i), there was no decreasing trend in A (sat) at a given g (s) and C (i) in droughted leaves, suggesting that the decline in A (sat) in field-grown cotton plants under a long-term drought can be attributed mainly to stomatal closure, but not to nonstomatal limitations. There was little evidence of an increase in thermal energy dissipation as indicated by the lack of a decrease in the photochemical efficiency of open PSII (F (v)'/F (m)') in droughted plants. On the basis of electron transport (ETR) and photochemical quenching (q (P)), however, we found evidence indicating that droughted cotton plants can circumvent the risk of excessive excitation energy in photosystem (PS) II by maintaining higher electron transport rates associated with higher N (area), even while photosynthetic rates were reduced by stomatal closure.

Current-sensing scanning near-field optical microscopy using a metal probe for nanometre-scale observation of electrochromic films.

A novel technique for scanning near-field optical microscopy capable of point-contact current-sensing was developed in order to investigate the nanometre-scale optical and electrical properties of electrochromic materials. An apertureless bent-metal probe was fabricated in order to detect optical and current signals at a local point on the electrochromic films. The near-field optical properties could be observed using the local field enhancement effect generated at the edge of the metal probe under p-polarized laser illumination. With regard to electrical properties, current signal could be detected with the metal probe connected to a high-sensitive current amplifier. Using the current-sensing scanning near-field optical microscopy, the surface topography, optical and current images of coloured WO3 thin films were observed simultaneously. Furthermore, nanometre-scale electrochromic modification of local bleaching could be performed using the current-sensing scanning near-field optical microscopy. The current-sensing scanning near-field optical microscopy has potential use in various fields of nanometre-scale optoelectronics.

Effects of deicing salt on the vitality and health of two spruce species, Picea abies Karst., and Picea glehnii Masters planted along roadsides in northern Japan.

In northern Japan, the growth of Picea abies Karst., and Picea glehnii Masters, which have been planted along the highways, is often suppressed due to several environmental stresses. To examine the adverse effects of deicing salt, the primary source of stress,we measured needle life span, photosynthetic capacity, and water potential and transpiration rate of the two spruce species at a site with damaged trees, near the roadside and a site with healthy trees, located far from the highway. Results from the analysis showed large amounts of sodium and chlorine in the soil and snow at the damaged site. These elements had accumulated in the needles of the spruce. Moreover, physiological traits of the spruce, at the damaged site were also affected. Therefore, we concluded that poor physiological traits might be attributed to an accumulation of deicing salt in the needles, resulting in the suppression of tree growth.

Leaf morphology and photosynthetic adjustments among deciduous broad-leaved trees within the vertical canopy profile.

Photosynthetic acclimation of deciduous broad-leaved tree species was studied along a vertical gradient within the canopy of a multi-species deciduous forest in northern Japan. We investigated variations in (1) local light regime and CO2 concentration ([CO2]), and (2) morphological (area, thickness and area per mass), biochemical (nitrogen and chlorophyll concentrations) and physiological (light-saturated photosynthetic rate) attributes of leaves of seven major species on three occasions (June, August and October). We studied early successional species, alder (Alnus hirsuta (Spach) Rupr.) and birch (Betula platyphylla var. japonica (Miq.) Hara); gap phase species, walnut (Juglans ailanthifolia Carrière) and ash (Fraxinus mandshurica var. japonica Rupr.); mid-successional species, basswood (Tilia japonica (Miq.) Simonk.) and elm (Ulmus davidiana var. japonica (Rehd.) Nakai); and the late-successional species, maple (Acer mono Bunge). All but maple initiated leaf unfolding from the lower part of the crown. The [CO2] within the vertical profile ranged from 320-350 ppm in the upper canopy to 405-560 ppm near the ground. The lowest and highest ambient [CO2] occurred during the day and during the night, respectively. This trend was observed consistently during the summer, but not when trees were leafless. Chlorophyll concentration was positively related to maximum photosynthetic rate within, but not among, species. Leaf senescence started from the inner part of the crown in alder and birch, but started either in the outer or top portion of the canopy of ash, basswood and maple. Chlorophyll (Chl) to nitrogen ratio in leaves increased with decreasing photon flux density. However, Chl b concentration in all species remained stable until the beginning of leaf senescence. Maximum photosynthetic rates observed in sun leaves of early successional species, gap phase or mid-successional species, and late successional species were 12.5-14.8 micromol m(-2) s(-1), 4.1-7.8 micromol m(-2) s(-1) and 3.1 micromol m(-2) s(-1), respectively.

Photoconductive imaging in a photon scanning tunnelling microscope capable of point-contact current sensing using a conductive fibre probe.

A photoconductive photon scanning tunnelling microscope was developed to investigate the point-contact photoconductive properties of condensed matter. In order to detect the current and the optical signal at a local point on a surface, we coated the edge of a bent type fibre probe with indium tin oxide. Thus it was possible to measure both photocurrent and optical property with subwavelength resolution. The performance of the novel microscope was evaluated by analysing an organic thin film of copper phthalocyanine (CuPc), which is known to be an efficient photoconductive material. Photocurrent and current-voltage characteristics were observed at the local point on the CuPc thin films. Furthermore, photoconductive images were obtained with topography and near-field optical imaging using this system. The photoconductive PSTM shows potential in various areas of future optics and electronics.

Manganese toxicity as indicated by visible foliar symptoms of Japanese white birch (Betula platyphylla var. japonica).

For the purpose of a field diagnosis of Mn toxicity, we showed the possibility of using visible foliar symptoms of Japanese white birch (Betula platyphylla var. japonica Hara) as indicator. To examine the relationship between the expression of visible symptoms and leaf Mn concentrations, white birch seedlings were grown under four different Mn levels: 1 mg Mn l-1 as control, 10, 50 and 100 mg Mn l-1. Foliar symptoms of Mn toxicity for white birch were: (1) chlorosis at entire young leaves in the 50 and 100 mg Mn l-1 treatments; and (2) brown speckles at the leaf marginal and interveinal area for old leaves in the treatments greater than 1 mg Mn l-1. Mn preferably accumulated into the leaf marginal and interveinal area, where the brown speckles were observed. The mechanism determining the expression of symptoms seems to be associated with the physiological state related to leaf age as well as Mn distribution and concentration within a leaf.

Application of chlorophyll fluorescence to evaluate Mn tolerance of deciduous broad-leaved tree seedlings native to northern Japan.

We used chlorophyll fluorescence to examine photosynthetic responses to excess Mn accumulation in leaves of four tree species differing in successional traits. Betula ermanii Cham. (Be) and Alnus hirsuta Turcz. (Ah) were studied as representatives of early-successional species. Ulmus davidiana Planch. var. japonica (Rehder) Nakai (Ud) was selected as a mid-successional species, and Acer mono Maxim. var. glabrum (Lév. et Van't.) Hara (Am) was chosen as a late-successional species. In Be, Ah and Am, high foliar concentrations of Mn had little effect on maximum photochemical efficiency of photosystem II (PSII), as indicated by the values of dark-adapted F(v)/F(m), whereas a significant decrease was observed in Ud. Photochemical quenching (qP) and the excitation capture efficiency of open PSII (F'(v)/F'(m)) decreased with increasing leaf Mn concentration at photosynthetic steady state after a 15-min exposure to 430 &mgr;mol m(-2) s(-1) PPFD. Compared with early-successional species, these decreases were greater in mid- and late-successional species leading to lower effective quantum efficiencies of PSII (DeltaF/F'(m) = qP x F'(v)/F'(m) = (F'(m) - F)/F'(m)). To determine the extent of photoinhibition, F(v)/F(m) of the illuminated leaves was remeasured after a 15-min dark period. Compared with the dark-adapted F(v)/F(m), we observed a significant decrease in F(v)/F(m) in Am leaves containing high concentrations of Mn. These chlorophyll fluorescence studies indicate that the early-successional species Be and Ah have a higher tolerance to excessive accumulations of Mn in leaves than the mid- and late-successional species Ud and Am.

Decrease in tumor volume and histologic response to intraarterial neoadjuvant chemotherapy in patients with cervical and endometrial adenocarcinoma.

Our purpose was to evaluate the utility of clinicopathological and biological markers prior to treatment in predicting the immediate response to chemotherapy in cervical and endometrial adenocarcinomas. Twelve patients with locally advanced cervical adenocarcinomas and 16 patients with endometrial adenocarcinomas received intraarterial neoadjuvant chemotherapy (NAC) consisting of cisplatin and doxorubicin before surgical resection. The decrease in tumor volume on magnetic resonance imaging (MRI) ([tumor volume before NAC - tumor volume after NAC]/tumor volume before NAC x 100) and the histologic response to NAC were assessed. Five factors prior to NAC (nuclear grade, pretreatment tumor volume, PCNA index, p53 protein expression, and DNA ploidy) were analyzed for correlation with the decrease in tumor volume and histologic response in cervical and endometrial adenocarcinoma, respectively. In cervical adenocarcinoma, patients with higher PCNA index tumor (> or = 40.2%) showed a significantly greater decrease in tumor volume than those with lower PCNA index (P < 0.05). In patients with endometrial adenocarcinoma, those with a smaller tumors (< 30.3 cm3) showed a significantly greater decrease than those with a larger tumors (P < 0.001). Tumors with higher PCNA index (> or = 31.5%) and negative p53 protein expression appeared to respond better than other tumors, but the difference was not statistically significant. Nuclear grade and DNA ploidy were not correlated with decrease in tumor volume either in cervical adenocarcinoma or in endometrial adenocarcinoma. Four cases of effective histologic response (2 complete responses [no microscopic residual tumor] and 2 marked responses [no macroscopic residual tumor]) were noted only in patients with endometrial adenocarcinoma who had a smaller tumor, higher PCNA index, and negative p53 protein expression. Pretreatment tumor volume and PCNA index were the only significant predictive factors (P < 0.05). Results suggest that the PCNA index in cervical and endometrial adenocarcinomas and the pretreatment tumor volume in endometrial adenocarcinoma appeared to be potentially useful in predicting the immediate response to the chemotherapy.

Antenatal diagnosis of aberrant umbilical vessels.

OBJECTIVE: To evaluate the antenatal screening of aberrant umbilical vessels and assess the association of fetal abnormality with these entities. STUDY DESIGN: 444 pregnant women were studied with routine obstetric ultrasound and Doppler color flow imaging in late second trimester or early third trimester. Fetal growth and anomaly, and the number of umbilical cord vessels were screened. RESULTS: Out of 444 subjects, 3 cases with discordant umbilical artery, 2 with four vessels in the umbilical cord, and 1 with single umbilical artery were detected (1.4%). Fetal anomaly was noted in 2 of 6 cases with aberrant umbilical vessels (33.3%). CONCLUSION: These results suggest that antenatal screening of umbilical cord vessels is necessary for detection of fetal anomalies.

Doppler ultrasound in a patient with ovarian Brenner tumor of low malignant potential: comparison with Gray-scale ultrasound, magnetic resonance imaging and tumor marker suggesting malignancy.

We present a postmenopausal patient with giant lower abdominal tumor. Gray-scale ultrasound and magnetic resonance imaging showed typical abnormal morphology suggesting malignancy. The serum CA 125 level was 69 U/ml, and that of CA 19-9 was 2,097 ng/ml. Transvaginal color and pulsed Doppler sonography of the tumor vasculature demonstrated low peak systolic velocity (6.7 cm/s) with low pulsatility (resistance index: 0.49). Total abdominal hysterectomy and bilateral salpingo-oophorectomy were performed. Histological diagnosis was ovarian Brenner tumor of low malignant potential. Transvaginal Doppler findings seemed to give specific information for the diagnosis in this case.

Comparison of photosynthetic responses to manganese toxicity of deciduous broad-leaved trees in northern Japan.

The effects of manganese (Mn) toxicity on photosynthesis of four tree species in northern Japan representing different successional traits were examined. The four species are: Betula ermanii (Be) and Alnus hirsuta (Ah) representing two early successional species, Ulmus davidiana var. japonica (Ud) as the mid-successional species, and Acer mono (Am) as the late successional species. Seedlings were grown hydroponically in a solution containing nutrients and Mn of four concentrations (1, 10, 50, 100 mg litre(-1)) for 50 days. Gas exchange measurements indicate that in all species, Mn accumulation in leaves resulted in the decline of light-saturated net photosynthetic rate ai ambient CO(2) pressure (35 Pa, Pn(amb)) and at saturating (5%) CO(2) pressure (Pn(sat)), and of carboxylation efficiency but has little effect on the maximum efficiency of photochemistry. Sensitivity to elevated levels of Mn differed among species where the decline of Pn(amb) was much more modest in the two early successional species of Be and Ah than the mid- and late successional species of Ud and Am. The same trends were observed in both Pn(sat) and carboxylation efficiency. Based on these results, we suggest that early successional species (Betula ermanii and Alnus hirsuta) have greater tolerance for excess Mn in leaves than mid- and late successional species.

Effect of serum from fertile and infertile patients with endometriosis on the development of mouse embryos.

OBJECTIVE: To evaluate the effect of serum from infertile and fertile patients with endometriosis on the development of 2-cell mouse embryos. PATIENTS: Serum was obtained from 26 infertile patients and 8 fertile patients with endometriosis. Mouse embryo development in serum samples was compared using chi 2 analysis. RESULTS: In the infertile group 23% of the embryos reached blastocyst stage, whereas 22 of the 26 samples were embryo toxic. In the fertile group significantly more embryos (45%) developed to blastocysts and only one serum samples was embryo toxic. CONCLUSION: The embryo toxicity of serum samples from patients with endometriosis is related to the infertility associated with the disease and not with the disease per se.

Intratumoral blood flow analysis in endometrial cancer: does it differ among individual tumor characteristics?

To evaluate whether intratumoral blood flow analysis in endometrial cancer provides individual tumor characteristics, 36 patients with endometrial cancer (5 in stage IA, 14 in stage IB, 5 in stage IC, 4 in stage II, and 8 in stage III) underwent transvaginal color and pulsed Doppler ultrasound before surgery. Histologically, there were 18 patients with well-differentiated adenocarcinoma, 8 with moderate differentiated adenocarcinoma, 4 with poorly differentiated adenocarcinoma, 4 with adenoacanthoma, and 2 with carcinosarcoma. Intratumoral blood flow was recorded, and peak systolic velocity (PSV) and resistance index (RI) were calculated. Endometrial thickness (ET) was also measured. There were no significant differences among PSV and RI values for each stage. There were also no significant differences among PSV and RI values for each histological diagnosis. ET in stages IA, IB, and II was significantly thinner than that in stage III (P < 0.05). Moreover, ET in stage IA was significantly thinner than that in stage IC (P < 0.05). There were significant differences in ET for some histological diagnoses. These results suggest that intratumoral blood flow analysis in endometrial cancer could not predict the tumor staging and histological diagnosis. However, in view of the small number of patients, these observations must be considered preliminary.

Prognostic application of magnetic resonance imaging in patients with endometriomas treated with gonadotrophin-releasing hormone analogue.

We evaluated the usefulness of magnetic resonance imaging (MRI) for assessing the response of patients with endometriomas to medical therapy. MRI was performed before and after treatment in 20 consecutive patients with at least one endometrioma with a maximal diameter >10 mm diagnosed by laparoscopy who received 900 microg of buserelin acetate daily for 6 months. Patients were categorized as good responders (group I, n = 13) and poor responders (group II, n = 7) depending on the results of a third-look laparoscopy performed 6 months after treatment. We determined the ratio of the signal intensity (SI) of the endometrioma to the SI of the gluteus maximus muscle on T2-weighted images [T2SI/M (muscle) SI] and the volume of the endometrium. The volume decreased by >50% in 61.5% of the good-response group and 57.1% of the poor-response group. There was no significant difference between the two groups. The T2SI/MSI decreased in 12 of 13 patients in group I but in only one of seven patients in group II, a significant difference (P < 0.05) between the two groups. In the good-response group, there was a positive linear correlation between the decrease in the volume of the endometrioma and the decrease in the T2SI/MSI after treatment (r = 0. 561, P < 0.05). Therefore, the T2SI/MSI determined from MR images may be useful in assessing the therapeutic response of patients with endometriomas.