Calvin cycle and guard cell metabolism impact stomatal function.

Stomatal conductance (gs) determines CO2 uptake for photosynthesis (A) and water loss through transpiration, which is essential for evaporative cooling and maintenance of optimal leaf temperature as well as nutrient uptake. Stomata adjust their aperture to maintain an appropriate balance between CO2 uptake and water loss and are therefore critical to overall plant water status and productivity. Although there is considerable knowledge regarding guard cell (GC) osmoregulation (which drives differences in GC volume and therefore stomatal opening and closing), as well as the various signal transduction pathways that enable GCs to sense and respond to different environmental stimuli, little is known about the signals that coordinate mesophyll demands for CO2. Furthermore, chloroplasts are a key feature in GCs of many species, however, their role in stomatal function is unclear and a subject of debate. In this review we explore the current evidence regarding the role of these organelles in stomatal behaviour, including GC electron transport and Calvin-Benson-Bassham (CBB) cycle activity as well as their possible involvement correlating gs and A along with other potential mesophyll signals. We also examine the roles of other GC metabolic processes in stomatal function.

The influence of rising tropospheric carbon dioxide and ozone on plant productivity.

Human activities result in a wide array of pollutants being released to the atmosphere. A number of these pollutants have direct effects on plants, including carbon dioxide (CO2 ), which is the substrate for photosynthesis, and ozone (O3 ), a damaging oxidant. How plants respond to changes in these atmospheric air pollutants, both directly and indirectly, feeds back on atmospheric composition and climate, global net primary productivity and ecosystem service provisioning. Here we discuss the past, current and future trends in emissions of CO2 and O3 and synthesise the current atmospheric CO2 and O3 budgets, describing the important role of vegetation in determining the atmospheric burden of those pollutants. While increased atmospheric CO2 concentration over the past 150 years has been accompanied by greater CO2 assimilation and storage in terrestrial ecosystems, there is evidence that rising temperatures and increased drought stress may limit the ability of future terrestrial ecosystems to buffer against atmospheric emissions. Long-term Free Air CO2 or O3 Enrichment (FACE) experiments provide critical experimentation about the effects of future CO2 and O3 on ecosystems, and highlight the important interactive effects of temperature, nutrients and water supply in determining ecosystem responses to air pollution. Long-term experimentation in both natural and cropping systems is needed to provide critical empirical data for modelling the effects of air pollutants on plant productivity in the decades to come.

Antenatal exposure to atenolol and retroperitoneal fibromatosis.

We present a case of retroperitoneal fibromatosis in a fetus whose mother took atenolol during pregnancy. A 25-year-old obese woman was treated for hypertension with 100 mg atenolol daily from the second month until the end of pregnancy. At 29 weeks, echography disclosed a retroperitoneal mass and at 37 weeks, a boy was delivered. A biopsy of the tumor showed a fibromatosis with medullary compression, treated by antimitotics until 3 months of age. At the age of 4, the mass had disappeared but severe scoliosis was present. This in utero exposure to atenolol drew our attention because the retroperitoneal localization of the tumor is similar to that of fibroses reported in adults after exposure to atenolol and for other reasons: transplacental carcinogenesis has been demonstrated in humans, at least for diethylstilboestrol, atenolol crosses the placental barrier, the drug was taken during nearly the whole pregnancy, and retroperitoneal fibromatosis is exceptional as a neonatal tumour.

Metastatic prostatic adenocarcinoma-diagnosed by bronchoalveolar lavage and tumour marker determination.

We report a patient who presented with a diffuse interstitial lung disease in whom clinical and radiologic investigation led to the suspicion of lymphangitis carcinomatosa. Bronchoalveolar lavage (BAL) was performed and revealed the presence of prostatic specific antigen (PSA) positive cells. A prostatic needle aspiration confirmed the diagnosis of adenocarcinoma. This case demonstrates the value of tumour marker determination in BAL.

[Spinal osteoid osteomas. Apropos of 4 cases]. / Ostéomes ostéoïdes rachidiens. A propos de 4 observations.

Spinal osteoid osteomas constitute a rare but perfectly curable cause of non-disc root pain. In discussing four cases (2 cervical and 2 lumbar), the authors stress that this disorder affects above all males under 30 and presents as vertebral column pain gradually becoming radicular in character; the pain, essentially nocturnal, is spectacularly but transiently relieved by salicylates and is accompanied by often frank stiffness of the spine. The diagnosis is based less on X rays and tomographs, than on isotope bone scanning, which reveals a focus of intense hyperfixation, and CAT scanning which shows a bony lacuna possibly with an opacity in the center producing a rosette shaped image. Block excision of the osteoid osteoma produces immediate relief for the patient and prevents recurrence which only occurs exceptionally.

Serum protein polymorphism in Papua New Guinea Eastern Highlands.

Four protein polymorphisms: haptoglobin (HP), group specific component (GC), third component of complement (C3) and transferrin (TF), were investigated in Baruya tribes and several other Anga tribes living high in the Wonenara and Marawaka valleys in Papua New Guinea Eastern Highlands. A non-Anga tribe, the Aziana or Kenaze was also sampled. TF*D variant was identified in every group except Usarumpia. A number of anhaptoglobinaemic individuals was noticed. Environmental factors causing hemolysis and haptoglobin consumption are suggested. HP*1 and GC*1 frequencies were high, as usually observed in New Guinea. The Anga tribes are protected from malaria and represent a model of human isolates. The present study confirms this situation.

Red cell enzyme polymorphisms in Papua New Guinea Eastern Highlands.

Ten red cell enzyme polymorphisms, malic dehydrogenase (MDH1), adenylate kinase (AK), phosphohexose isomerase (PHI), adenosine deaminase (ADA), esterase D (ESD), glutamic pyruvic transaminase (GPT), acid phosphatase (ACP1), phosphoglucomutase 1 and 2 (PGM1, PGM2), phosphogluconate dehydrogenase (PGD) were investigated in the Baruya tribe and several Anga tribes living high in the Wonenara and Marawaka valleys in Papua New Guinea Eastern Highlands (6.5S, 145.5E). Also a non-Anga tribe, the Aziana or Kenaze, was sampled. Variants were observed in ADA, PGM1 and PGM2. AK and PHI were monomorphic, all subjects being AK 1 and PHI 1; MDH1 was also monomorphic in Anga while variants were observed in Aziana. This latter tribe differed markedly in each system from the Anga peoples.

Blood groups in Papua New Guinea Eastern Highlands.

Blood group polymorphisms were analysed in inhabitants of Papua New Guinea Eastern Highlands. The aim of the study was to assess the situation of the Baruya tribe among other Anga peoples: Youwarounatche, Andje, Usarumpia, Langimar. A non-Anga tribe, the Aziana, was also sampled. ABO, RH, MNS, P, KEL, FY and JK systems were tested in each group. ABO*O gene was predominant, ABO*Aint was relatively high, ABO*B was rare in all tribes and absent in the Usarumpia tested. The Ns haplotype was the most frequent in MNS system. All tested subjects were RH*D, KEL (-) and FY (a+b-), with very few exceptions. The presence of one CcdEe and 5 FY (a+b+) subjects may be due to foreign admixture. A noteworthy genetic microdifferentiation was observed between tribes. Geographical isolation and genetic drift has played an important role in the differentiation of the various groups.