Soil compaction. A role for ethylene in regulating leaf expansion and shoot growth in tomato?

The role of ethylene in regulating growth in tomato (Lycopersicon esculentum Mill.) during compaction stress was examined using wild-type (cv Ailsa Craig) and transgenic (ACO1(AS)) genotypes; the latter has a reduced capacity to produce ethylene. Ethephon or silver ions were applied to increase ethylene production or block its action. Shoot growth in both genotypes was comparable in uncompacted (1.1 g cm(-3)) and uniformly compacted soil (1.5 g cm(-3)). However, a 1.1/1.5-g cm(-3) split-pot treatment invoked marked genotypic differences: growth was reduced in cv Ailsa Craig but was comparable to uncompacted control plants in ACO1(AS). As xylem sap abscisic acid levels were similar, abscisic acid was not responsible for inhibiting growth in cv Ailsa Craig. These genotypic differences in growth were accompanied by increased ethylene evolution in cv Ailsa Craig, suggesting that the ability of ACO1(AS) to maintain growth in the split-pot treatment reflected its lower ethylene levels, a view supported by the observation that excising the roots in the compacted compartment reduced ethylene evolution and restored shoot growth in cv Ailsa Craig. Treatment with silver restored shoot growth in cv Ailsa Craig, whereas treatment with ethephon reduced growth in ACO1(AS). Thus, ethylene apparently has a key role in determining growth when tomato plants encounter differential soil compaction.

Adenoid cystic carcinoma of the Bartholin's gland: the University of Michigan experience.

Adenoid cystic carcinoma of the Bartholin's gland has been encountered in 11 patients at the University of Michigan Medical Center since 1936. At the time of presentation the average age was 48.9 years, the lesion size was between 0.5 to 4 cm. The presenting symptoms were pain and/or pruritis associated with a solitary mass. Early in this series, excisional biopsy was used to treat eight patients. The last three patients have been treated with a radical vulvectomy and unilateral or bilateral groin lymph node dissection. Local recurrence has occurred in five patients and distant recurrence in four patients. In spite of the high recurrence rate, 5- and 10-year survival has been high with all seven evaluable patients surviving 5 and 10 years. However, adenoid cystic carcinoma of the vulva is associated with late recurrences and metastases: three patients were dead of disease at 12, 15 and 31 years after initial diagnosis.

Dielectric behavior of SrTiO3 and YiBa2CU3Ox at 10.6 GHz using a microwave resonant cavity as a probe

A cylindrical microwave resonant cavity operating in the TE011 mode was used to study the dielectric response of SrTiO3 and YiBa2CU3Ox. The microwave dielectric response of the powdered samples of these materials is studied as a function of temperature at a frequency of 10.6 GHz. For this study, a very precise heating and cooling system was designed to control the temperature accurately to a tenth of a degree. The real and imaginary parts of the complex permittivity were studied using Slater's Perturbation equations. The relaxation times of these materials are derived using Debye's equations for polar molecules.

Frequency of the prolificacy gene in flocks of Indonesian thin tail sheep: a review.

Indonesian thin tail (ITT) sheep have a major prolificacy gene (FecJ(F)), the frequency of which is higher in the new born lambs, than in the remainder of the flock when mating is random, because carrier ewes produce more progeny than do non carriers. The frequency of the gene may vary between flocks, but remains relatively stable in flocks with established husbandry procedures. The countermanding selection pressures maintaining the equilibrium value for the frequency of FecJ(F) are mainly those deriving from higher mortality rates of lambs in larger litters. Embryo survival is not significantly different across the range of ovulation rates in ITT ewes, in contrast to observations in other prolific breeds. Generation intervals and the incidences of metabolic and infectious diseases in ewes carrying larger litters can also affect the frequency of FecJ(F) in flocks. In turn, each of the factors affecting the frequency of FecJ(F) is modulated by the level of nutrition and management in each flock. The distribution of prolificacy genotypes in the ewes of a standard flock is calculated as FecJ(F)FecJ(F)/12; FecJ(F)FecJ(+)/44; FecJ(+)FecJ(+)/44 giving a frequency of 0.34 for FecJ(F). The frequency of FecJ(F) is then 0.43 in the lambs at birth, when their numbers have been amplified in the carrier ewes. There are heavier metabolic demands on ewes carrying larger litters and the foetuses constitute a higher proportion of weight gain during pregnancy. Consequently, more of the lambs of carrier ewes are smaller and weaker at birth, and the reserves of the ewes for colostrum and milk production are depleted. When low lamb survival rates in larger litters are considered, the frequency of FecJ(F) falls to 0.35 in the lambs at weaning in lean years and 0.38 in middling years. At a high level of husbandry, ewe weight gains during pregnancy and lamb survival rates improve substantially, and after 3 years, the frequency of FecJ(F) in the lambs at birth is estimated to have risen to 0.49; and 0.47 at weaning.

Spontaneous resolution of a gallstone ileus.

Gallstone ileus is an uncommon complication of cholelithiasis, usually associated with an internal biliary fistula. Management of gallstone ileus is surgical with enterolithotomy the procedure of choice, followed by fistula closure either as a one or two stage procedure. In this case a 66 year old female presented with colicky abdominal pain, computed tomography (CT) clearly showing a gallstone ileus and cholecystoduodenal fistula. Despite this the patient refused surgery and went on to have spontaneous resolution of the obstruction and passage of gallstones.

Management of Urinary Tract Infections in the Adolescent Male.

Although urinary tract infections are uncommon in adolescent boys, they are easily treated. The author chronicles the management of UTIs with concise descriptions of their history, pathophysiology, epidemiology, symptoms and signs, laboratory tests, diagnostic problems, treatment, and prognosis. Costs of antibiotics for UTIs are compared.