Improving stress tolerance is a major goal for agriculture. Trehalose is a key molecule involved in drought tolerance in anhydrobiotic organisms. Here we describe the construction of a chimeric translational fusion of yeast trehalose-6-phosphate synthase and trehalose-6-phosphate phosphatase. This construct was overexpressed in yeast cells displaying both TPS and TPP enzyme activities and trehalose biosynthesis capacity. In Arabidopsis thaliana, the gene fusion was overexpressed using either the 35S promoter or the stress-regulated rd29A promoter. Transgene insertion in the genome was checked by PCR and transcript expression by RT-PCR. Several independent homozygous lines were selected in the presence of kanamycin and further analyzed. Trehalose was accumulated in all these lines at low levels. No morphological or growth alterations were observed in lines overexpressing the TPS1-TPS2 construct, whereas plants overexpressing the TPS1 alone under the control of the 35S promoter had aberrant growth, color and shape. TPS1-TPS2 overexpressor lines were glucose insensitive, consistent with a suggested role of trehalose/T6P in modulating sugar sensing and carbohydrate metabolism. Moreover, TPS1-TPS2 lines displayed a signiWcant increase in drought, freezing, salt and heat tolerance. This is the Wrst time that trehalose accumulation in plants is shown to protect against freezing and heat stress. Therefore, these results demonstrate that engineering trehalose metabolism with a yeast TPS-TPP bifunctional enzyme confers multiple stress protection in plants, comprising a potential tool to improve stress-tolerance in crops.
When the time between the start of ampicillin prophylaxis and delivery is at least 2 hours, vertical transmission of group B streptococcus is minimized.
Reluctance to recommend lung cancer surgery for octogenarians is partly based on the expectation that the rate of complications and mortality is higher in this group of patients, and on the impression that the life expectancy of an octogenarian with lung cancer is limited by death from natural causes. Moreover, the belief that radiation therapy and observation yield similar results to surgery in early-stage disease have influenced low resection rates in this population. Nevertheless, advances in surgical techniques, anaesthesia and postoperative care have made surgical lung resection a safer procedure than it was in the past. Judging from the more recent findings, surgery should not be withheld because of postoperative mortality, but suboptimal or palliative treatment may be necessary in patients with poor physical or mental function. To enable informed decision-making, both patients and clinicians need information on the risks of surgical treatment. In this review, available information from the literature was collected in an effort to understand the real benefit of surgical treatment in octogenarians with non-small-cell lung cancer, and to determine what should be done or avoided during the selection course.
Bronchiectasis is characterized by irreversible widening of the medium-sized airways, with inflammation, chronic bacterial infection and destruction of the bronchial walls. Exercise or inspiratory muscle training may improve quality of life and exercise endurance in people with non-cystic fibrosis bronchiectasis. Prolonged-use antibiotics improve clinical response rates, but may not reduce exacerbation rates or lung function. Surgery is often considered for people with extreme damage to one or two lobes of the lung who are at risk for severe infection or bleeding. In this review, the authors will focus on non-cystic fibrosis bronchiectasis, pointing out the differences in management when compared with the cystic fibrosis context, with special emphasis on surgical management.
A 27-year-old woman with a GH-secreting pituitary macroadenoma was treated with continuous s.c. infusion of octreotide prior to surgical resection. Subsequently, she was found to be 6 months pregnant. Fetal echographs were normal, the newborn had no malformation, and postnatal development was normal.
We reviewed 488 twin pregnancies that resulted in the birth of neonates weighing 1000 g or more. Complications were present in 56.7% of all pregnancies; most common were threat of premature labor (17.4%) and preeclampsia (14.5%). Perinatal mortality was 31.8 per thousand. Eighty percent of neonatal deaths in twin pregnancies involved newborns weighing less than 2000 g. Twin pregnancies are high risk pregnancies and benefit from early diagnosis, prevention and treatment of the threat of premature birth.
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