Evidence for age- and size-mediated controls of tree growth from grafting studies.

Vegetative propagation techniques such as grafting can be used, in conjunction with field studies, to decouple the relative effects of age and size on tree metabolism and growth. Despite interest in this approach, little attention has been paid to the best metrics for assessing the growth performance of grafted plants over time. Based on an analysis of the grafting literature and our own data, we show that the choice of metrics to assess tree growth can entirely change the conclusions reached about the relative importance of age versus size. We recommend that absolute as well as relative rates of growth are calculated and that scion size be standardized as much as possible at the start of the experiment. Once proper metrics are chosen, all of the available published evidence is largely concordant with two concepts: (1) age-mediated controls of tree growth are likely to be important during the first few years of a tree's life (before phase change); and (2) after the first few years of a tree's life, size-mediated factors largely prevail over age-mediated factors in determining tree growth rates. We found no support for theories invoking age-mediated sink limitations in old trees.

Observational evidence on the effects of mega-fires on the frequency of hydrogeomorphic hazards. The case of the Peloponnese fires of 2007 in Greece.

Even though rare, mega-fires raging during very dry and windy conditions, record catastrophic impacts on infrastructure, the environment and human life, as well as extremely high suppression and rehabilitation costs. Apart from the direct consequences, mega-fires induce long-term effects in the geomorphological and hydrological processes, influencing environmental factors that in turn can affect the occurrence of other natural hazards, such as floods and mass movement phenomena. This work focuses on the forest fire of 2007 in Peloponnese, Greece that to date corresponds to the largest fire in the country's record that burnt 1773km2, causing 78 fatalities and very significant damages in property and infrastructure. Specifically, this work examines the occurrence of flood and mass movement phenomena, before and after this mega-fire and analyses different influencing factors to investigate the degree to which the 2007 fire and/or other parameters have affected their frequency. Observational evidence based on several data sources collected during the period 1989-2016 show that the 2007 fire has contributed to an increase of average flood and mass movement events frequency by approximately 3.3 and 5.6 times respectively. Fire affected areas record a substantial increase in the occurrence of both phenomena, presenting a noticeably stronger increase compared to neighbouring areas that have not been affected. Examination of the monthly occurrence of events showed an increase even in months of the year were rainfall intensity presented decreasing trends. Although no major land use changes has been identified and chlorophyll is shown to recover 2years after the fire incident, differences on the type of vegetation as tall forest has been substituted with lower vegetation are considered significant drivers for the observed increase in flood and mass movement frequency in the fire affected areas.

Multimodal cancer chemotherapy during the first and second trimester of pregnancy: a case report.

This paper reports treatment with combined chemotherapy during pregnancy. A 39-year-old woman with breast cancer was given adjuvant chemotherapy including cyclophosphamide, methotrexate and 6-fluorouracil from the 6th to the 24th week of gestation. The possibility of teratogenic effects on the fetus was explained to the patient however she refused to terminate the pregnancy. A 30-week male infant with only a minor malformation was delivered. The authors reviewed the literature regarding chemotherapeutic agents given during the first trimester of pregnancy. Most cytotoxic drugs have teratogenic effects on experimental animal subjects. However, actual data on human fetuses are sparse because of the variety of therapeutic regimens and the rarity of administering chemotherapy during pregnancy. The long-term effects of exposure to cytotoxic drugs in utero, needs further research.

Infantile myofibromatosis with visceral involvement and complete spontaneous regression.

Infantile myofibromatosis is an unusual mesenchymal disorder characterized by the proliferation of tumors in the skin, muscle, bone, and viscera. Two types can be distinguished; the solitary type, defined by the presence of one nodule in the skin, muscle, bone or subcutaneous tissue; and the multicentric type which can be divided into two sub-types. In the first sub-type the lesions are multicentric but without visceral involvement, while in the second, visceral involvement is present. The prognosis of the disease depends on whether visceral involvement is present. Solitary and multicentric nodules without visceral involvement usually have excellent prognosis with spontaneous regression of lesions within 1 to 2 years of diagnosis. On the other hand, visceral lesions are associated with a significant morbidity and mortality, resulting from vital organ obstruction, failure to thrive, or infection. Death in these cases often occurs at birth, or soon after, and is usually due to cardio-pulmonary or gastrointestinal complications. The case being reported here, is that of a female newborn who had multiple skin, subcutaneous tissue, skeletal muscle, bone, and lung lesions immediately after bith. At the age of three years, the child is in good health, her psychomotor development is in accordance with her age group, and the lesions have completely regressed. This is a case of the multicentic type of infantile myofibromatosis with visceral involvement, where all lesions have spontaneously regressed. This is a rarity since the prognosis in the majority of such cases is poor.

Neonatal screening for developmental dysplasia of the hip on the maternity wards in Crete, Greece. correlation to risk factors.

OBJECTIVE: To evaluate the effects of ultrasound examination of newborns in early detection and management of developmental dysplasia of the hip (DDH), and its correlation to known risk factors. The incidence of DDH in newborns throughout the general population of Crete has also been investigated. METHODS: From 1996 to 2000, 6,140 full-term newborns were examined in the Maternity Department of the University Hospital. All received standard assessments, with their medical history recorded, and a physical examination performed on the first and the fifth postpartum days. Ultrasonography of both hips using the Graf technique was performed on the 15th day after birth on both high-risk newborns and those with any clinical suspicion of DDH. Treatment was initiated according to the Graf classification. RESULTS: Ultrasound examination was performed on 220 newborns (3.58%). Ultrasound findings were positive in 65 neonates (10.83 per 1,000). Twenty-one neonates whose clinical examination was normal, but who underwent ultrasound because of the presence of risk factors had pathological findings on the hip sonography (32.30%) CONCLUSION: The incidence of DDH in Crete is estimated to be 10.83 per 1,000; higher than in the rest of Greece. Medical and family histories and clinical examination play an important role in the diagnosis of hip instability. Selective ultrasonography for all infants with risk factors, and those with clinical abnormality of the hip, is an adjunctive tool which aids early diagnosis and offers higher control in the results of treatment.

Breast feeding--when nature fails to satisfy.

Human milk is the ideal source of nutrition for the healthy neonate. Milk from the mother whose diet is sufficient will supply the necessary nutrients. It is a considerable problem to discern if the milk supply is the adequate quantity for the infant. If the infant's water and caloric needs are not met for several days, signs and symptoms of hypernatremic dehydration >10% may develop. This report presents a case of a 15-day-old, breast-fed infant who developed significant hypernatremic dehydration.

Association between duration of neonatal hospital stay and morbidity in the first month of life.

The morbidity of 506 healthy full-term newborns was studied in the first month of life in relation to the time they stayed in the hospital. The average time for the newborns who were born by vaginal delivery was 73.3+/-11.7 hours, while for those who were born by cesarean section it was 135+31.5 hours. Thirty-seven newborns presented health problems during the neonatal period (7.3%) and only 2% needed hospital readmission. The commonest problem in the newborns we studied was jaundice which appeared from the fourth to sixth day of life. During the second fortnight the commonest problems were infections of the respiratory tract. From the results of our study it is obvious that only a small percentage of readmissions could have been avoided if the original stay in hospital had been prolonged.

Size-mediated ageing reduces vigour in trees.

There is increasing interest in understanding the costs and benefits of increased size and prolonged lifespan for plants. Some species of trees can grow more than 100 m in height and can live for several millennia, however whether these achievements are obtained at the cost of some other physiological functions is currently unclear. As increases in size are usually associated with ageing, it is also unclear whether observed reductions in growth rates and increased mortality rates are a function of size or of age per se. One theory proposes that reduced growth after the start of the reproductive phase is caused by cellular senescence. A second set of theories has focussed instead on plant size and the increased respiratory burdens or excessive height. We report on experimental manipulations to separate the effects of extrinsic factors such as size from those of intrinsic factors such as age for four tree species of contrasting phylogeny and life history. For each species, we measured growth, gas exchange and leaf biochemical properties for trees of different ages and sizes in the field and on propagated material obtained from the same genetic individuals but now all of small similar size in our common gardens. For all species, evidence indicated that size, not cellular senescence, accounted for the observed age-related declines in relative growth rates and net assimilation rates. Two species exhibited evidence of genetic control on leaf characters such as specific leaf area, although size also exerted an independent, and stronger, effect. We found partial support for the theory of hydraulic limitations to tree growth. The lack of a marked separation of soma and germline, an unlimited proliferation potential of meristem cells and the exponential increase in reproductive effort with size all help explain the lack of a senescence-induced decline in trees. It is possible that trees much older than the ones we sampled exhibit senescence symptoms.

Spontaneous intestinal perforation in a full-term infant: association with infection.

The term spontaneous intestinal perforation suggests a perforation in the gastrointestinal tract of a newborn of no demonstrable cause. Only a few cases have been described in full-term newborns. The aetiology and pathogenesis of the disease are unknown although multiple theories have been proposed. Some authors suggest ischemia as the most likely cause. Conditions associated with fetal or neonatal hypoxia are important antecedents for this emerging distinct entity. We present a case of a spontaneous, intestinal perforation in a full-term neonate with urinary tract infection. There was no clinical evidence of necrotizing enterocolitis or bowel obstruction. Radiological images revealed a pneumoperitoneum. An emergency explorative laparotomy was performed. A localized linear perforation was identified in the transverse colon. Pathological examination of the resected specimens failed to reveal any etiology for the perforation. The neonate recovered rapidly, with no gastrointestinal complications. In our case none of the factors which have previously been associated with intestinal perforation could be implicated. We suggest that focal intestinal perforation is possibly the result of infection. Further studies, including careful recording of cases and close histopathological examination of resected specimens, are required in order to provide more information and improve our understanding of the aetiology of this rare occurance.

Anemia due to massive chronic foetomaternal hemorrhage.

We report a case of massive chronic foetomaternal hemorrhage. The labor course was uncomplicated. The newborn presented with pallor. tachypnea, and moderate hepatosplenomegaly. The initial hemoglobin was 6.5 g/dl. The Kleihauer-Betke stain on a maternal blood sample was 12%, which is equivalent to 540 ml of fetal blood in the maternal circulation. A clot in the umbilical vein was demonstrated sonographically. The possible association of foetomaternal hemorrhage with umbilical vein thrombosis is discussed.